[libcxx-commits] [libcxx] [libc++][C++03] Copy the LLVM 19 headers (PR #108999)
Nikolas Klauser via libcxx-commits
libcxx-commits at lists.llvm.org
Tue Sep 17 08:57:10 PDT 2024
https://github.com/philnik777 created https://github.com/llvm/llvm-project/pull/108999
None
>From 0dcf755a3e8fe605a5c6546c84997885ffc96b1a Mon Sep 17 00:00:00 2001
From: Nikolas Klauser <nikolasklauser at berlin.de>
Date: Tue, 17 Sep 2024 15:32:16 +0200
Subject: [PATCH] [libc++][C++03] Copy the LLVM 19 headers
---
libcxx/include/__cxx03/CMakeLists.txt | 1092 +++
.../__cxx03/__algorithm/adjacent_find.h | 58 +
libcxx/include/__cxx03/__algorithm/all_of.h | 32 +
libcxx/include/__cxx03/__algorithm/any_of.h | 32 +
.../__cxx03/__algorithm/binary_search.h | 39 +
libcxx/include/__cxx03/__algorithm/clamp.h | 44 +
libcxx/include/__cxx03/__algorithm/comp.h | 49 +
.../__cxx03/__algorithm/comp_ref_type.h | 67 +
libcxx/include/__cxx03/__algorithm/copy.h | 123 +
.../__cxx03/__algorithm/copy_backward.h | 137 +
libcxx/include/__cxx03/__algorithm/copy_if.h | 34 +
.../__cxx03/__algorithm/copy_move_common.h | 114 +
libcxx/include/__cxx03/__algorithm/copy_n.h | 60 +
libcxx/include/__cxx03/__algorithm/count.h | 92 +
libcxx/include/__cxx03/__algorithm/count_if.h | 35 +
libcxx/include/__cxx03/__algorithm/equal.h | 133 +
.../include/__cxx03/__algorithm/equal_range.h | 85 +
libcxx/include/__cxx03/__algorithm/fill.h | 45 +
libcxx/include/__cxx03/__algorithm/fill_n.h | 98 +
libcxx/include/__cxx03/__algorithm/find.h | 181 +
libcxx/include/__cxx03/__algorithm/find_end.h | 225 +
.../__cxx03/__algorithm/find_first_of.h | 55 +
libcxx/include/__cxx03/__algorithm/find_if.h | 32 +
.../include/__cxx03/__algorithm/find_if_not.h | 32 +
.../__cxx03/__algorithm/find_segment_if.h | 62 +
libcxx/include/__cxx03/__algorithm/fold.h | 128 +
libcxx/include/__cxx03/__algorithm/for_each.h | 57 +
.../include/__cxx03/__algorithm/for_each_n.h | 41 +
.../__cxx03/__algorithm/for_each_segment.h | 53 +
libcxx/include/__cxx03/__algorithm/generate.h | 29 +
.../include/__cxx03/__algorithm/generate_n.h | 33 +
.../__cxx03/__algorithm/half_positive.h | 37 +
.../__cxx03/__algorithm/in_found_result.h | 54 +
.../__cxx03/__algorithm/in_fun_result.h | 54 +
.../__cxx03/__algorithm/in_in_out_result.h | 59 +
.../__cxx03/__algorithm/in_in_result.h | 56 +
.../__cxx03/__algorithm/in_out_out_result.h | 57 +
.../__cxx03/__algorithm/in_out_result.h | 56 +
libcxx/include/__cxx03/__algorithm/includes.h | 79 +
.../__cxx03/__algorithm/inplace_merge.h | 240 +
libcxx/include/__cxx03/__algorithm/is_heap.h | 38 +
.../__cxx03/__algorithm/is_heap_until.h | 62 +
.../__cxx03/__algorithm/is_partitioned.h | 37 +
.../__cxx03/__algorithm/is_permutation.h | 308 +
.../include/__cxx03/__algorithm/is_sorted.h | 38 +
.../__cxx03/__algorithm/is_sorted_until.h | 51 +
.../include/__cxx03/__algorithm/iter_swap.h | 31 +
.../__cxx03/__algorithm/iterator_operations.h | 223 +
.../__algorithm/lexicographical_compare.h | 57 +
.../lexicographical_compare_three_way.h | 125 +
.../include/__cxx03/__algorithm/lower_bound.h | 109 +
.../include/__cxx03/__algorithm/make_heap.h | 60 +
.../__cxx03/__algorithm/make_projected.h | 106 +
libcxx/include/__cxx03/__algorithm/max.h | 58 +
.../include/__cxx03/__algorithm/max_element.h | 51 +
libcxx/include/__cxx03/__algorithm/merge.h | 69 +
libcxx/include/__cxx03/__algorithm/min.h | 58 +
.../include/__cxx03/__algorithm/min_element.h | 71 +
.../__cxx03/__algorithm/min_max_result.h | 56 +
libcxx/include/__cxx03/__algorithm/minmax.h | 59 +
.../__cxx03/__algorithm/minmax_element.h | 100 +
libcxx/include/__cxx03/__algorithm/mismatch.h | 217 +
libcxx/include/__cxx03/__algorithm/move.h | 127 +
.../__cxx03/__algorithm/move_backward.h | 137 +
.../__cxx03/__algorithm/next_permutation.h | 75 +
libcxx/include/__cxx03/__algorithm/none_of.h | 32 +
.../include/__cxx03/__algorithm/nth_element.h | 261 +
.../__cxx03/__algorithm/partial_sort.h | 91 +
.../__cxx03/__algorithm/partial_sort_copy.h | 106 +
.../include/__cxx03/__algorithm/partition.h | 90 +
.../__cxx03/__algorithm/partition_copy.h | 43 +
.../__cxx03/__algorithm/partition_point.h | 44 +
libcxx/include/__cxx03/__algorithm/pop_heap.h | 81 +
.../__cxx03/__algorithm/prev_permutation.h | 75 +
libcxx/include/__cxx03/__algorithm/pstl.h | 663 ++
.../include/__cxx03/__algorithm/push_heap.h | 84 +
.../__algorithm/ranges_adjacent_find.h | 83 +
.../__cxx03/__algorithm/ranges_all_of.h | 74 +
.../__cxx03/__algorithm/ranges_any_of.h | 74 +
.../__algorithm/ranges_binary_search.h | 73 +
.../__cxx03/__algorithm/ranges_clamp.h | 66 +
.../__cxx03/__algorithm/ranges_contains.h | 66 +
.../__algorithm/ranges_contains_subrange.h | 97 +
.../include/__cxx03/__algorithm/ranges_copy.h | 71 +
.../__algorithm/ranges_copy_backward.h | 69 +
.../__cxx03/__algorithm/ranges_copy_if.h | 87 +
.../__cxx03/__algorithm/ranges_copy_n.h | 81 +
.../__cxx03/__algorithm/ranges_count.h | 66 +
.../__cxx03/__algorithm/ranges_count_if.h | 79 +
.../__cxx03/__algorithm/ranges_ends_with.h | 201 +
.../__cxx03/__algorithm/ranges_equal.h | 109 +
.../__cxx03/__algorithm/ranges_equal_range.h | 80 +
.../include/__cxx03/__algorithm/ranges_fill.h | 62 +
.../__cxx03/__algorithm/ranges_fill_n.h | 53 +
.../include/__cxx03/__algorithm/ranges_find.h | 80 +
.../__cxx03/__algorithm/ranges_find_end.h | 103 +
.../__algorithm/ranges_find_first_of.h | 106 +
.../__cxx03/__algorithm/ranges_find_if.h | 75 +
.../__cxx03/__algorithm/ranges_find_if_not.h | 69 +
.../__cxx03/__algorithm/ranges_find_last.h | 175 +
.../__cxx03/__algorithm/ranges_for_each.h | 81 +
.../__cxx03/__algorithm/ranges_for_each_n.h | 64 +
.../__cxx03/__algorithm/ranges_generate.h | 73 +
.../__cxx03/__algorithm/ranges_generate_n.h | 65 +
.../__cxx03/__algorithm/ranges_includes.h | 98 +
.../__algorithm/ranges_inplace_merge.h | 84 +
.../__cxx03/__algorithm/ranges_is_heap.h | 81 +
.../__algorithm/ranges_is_heap_until.h | 81 +
.../__algorithm/ranges_is_partitioned.h | 86 +
.../__algorithm/ranges_is_permutation.h | 107 +
.../__cxx03/__algorithm/ranges_is_sorted.h | 67 +
.../__algorithm/ranges_is_sorted_until.h | 82 +
.../__algorithm/ranges_iterator_concept.h | 56 +
.../ranges_lexicographical_compare.h | 106 +
.../__cxx03/__algorithm/ranges_lower_bound.h | 73 +
.../__cxx03/__algorithm/ranges_make_heap.h | 85 +
.../include/__cxx03/__algorithm/ranges_max.h | 103 +
.../__cxx03/__algorithm/ranges_max_element.h | 69 +
.../__cxx03/__algorithm/ranges_merge.h | 138 +
.../include/__cxx03/__algorithm/ranges_min.h | 95 +
.../__cxx03/__algorithm/ranges_min_element.h | 81 +
.../__cxx03/__algorithm/ranges_minmax.h | 175 +
.../__algorithm/ranges_minmax_element.h | 78 +
.../__cxx03/__algorithm/ranges_mismatch.h | 100 +
.../include/__cxx03/__algorithm/ranges_move.h | 74 +
.../__algorithm/ranges_move_backward.h | 76 +
.../__algorithm/ranges_next_permutation.h | 78 +
.../__cxx03/__algorithm/ranges_none_of.h | 75 +
.../__cxx03/__algorithm/ranges_nth_element.h | 84 +
.../__cxx03/__algorithm/ranges_partial_sort.h | 82 +
.../__algorithm/ranges_partial_sort_copy.h | 114 +
.../__cxx03/__algorithm/ranges_partition.h | 88 +
.../__algorithm/ranges_partition_copy.h | 110 +
.../__algorithm/ranges_partition_point.h | 93 +
.../__cxx03/__algorithm/ranges_pop_heap.h | 86 +
.../__algorithm/ranges_prev_permutation.h | 78 +
.../__cxx03/__algorithm/ranges_push_heap.h | 85 +
.../__cxx03/__algorithm/ranges_remove.h | 68 +
.../__cxx03/__algorithm/ranges_remove_copy.h | 81 +
.../__algorithm/ranges_remove_copy_if.h | 95 +
.../__cxx03/__algorithm/ranges_remove_if.h | 89 +
.../__cxx03/__algorithm/ranges_replace.h | 68 +
.../__cxx03/__algorithm/ranges_replace_copy.h | 93 +
.../__algorithm/ranges_replace_copy_if.h | 98 +
.../__cxx03/__algorithm/ranges_replace_if.h | 81 +
.../__cxx03/__algorithm/ranges_reverse.h | 79 +
.../__cxx03/__algorithm/ranges_reverse_copy.h | 70 +
.../__cxx03/__algorithm/ranges_rotate.h | 71 +
.../__cxx03/__algorithm/ranges_rotate_copy.h | 68 +
.../__cxx03/__algorithm/ranges_sample.h | 74 +
.../__cxx03/__algorithm/ranges_search.h | 134 +
.../__cxx03/__algorithm/ranges_search_n.h | 116 +
.../__algorithm/ranges_set_difference.h | 109 +
.../__algorithm/ranges_set_intersection.h | 114 +
.../ranges_set_symmetric_difference.h | 114 +
.../__cxx03/__algorithm/ranges_set_union.h | 115 +
.../__cxx03/__algorithm/ranges_shuffle.h | 72 +
.../include/__cxx03/__algorithm/ranges_sort.h | 84 +
.../__cxx03/__algorithm/ranges_sort_heap.h | 85 +
.../__algorithm/ranges_stable_partition.h | 92 +
.../__cxx03/__algorithm/ranges_stable_sort.h | 82 +
.../__cxx03/__algorithm/ranges_starts_with.h | 95 +
.../__cxx03/__algorithm/ranges_swap_ranges.h | 70 +
.../__cxx03/__algorithm/ranges_transform.h | 177 +
.../__cxx03/__algorithm/ranges_unique.h | 82 +
.../__cxx03/__algorithm/ranges_unique_copy.h | 120 +
.../__cxx03/__algorithm/ranges_upper_bound.h | 74 +
libcxx/include/__cxx03/__algorithm/remove.h | 46 +
.../include/__cxx03/__algorithm/remove_copy.h | 34 +
.../__cxx03/__algorithm/remove_copy_if.h | 34 +
.../include/__cxx03/__algorithm/remove_if.h | 45 +
libcxx/include/__cxx03/__algorithm/replace.h | 30 +
.../__cxx03/__algorithm/replace_copy.h | 37 +
.../__cxx03/__algorithm/replace_copy_if.h | 37 +
.../include/__cxx03/__algorithm/replace_if.h | 30 +
libcxx/include/__cxx03/__algorithm/reverse.h | 62 +
.../__cxx03/__algorithm/reverse_copy.h | 30 +
libcxx/include/__cxx03/__algorithm/rotate.h | 198 +
.../include/__cxx03/__algorithm/rotate_copy.h | 29 +
libcxx/include/__cxx03/__algorithm/sample.h | 123 +
libcxx/include/__cxx03/__algorithm/search.h | 192 +
libcxx/include/__cxx03/__algorithm/search_n.h | 155 +
.../__cxx03/__algorithm/set_difference.h | 79 +
.../__cxx03/__algorithm/set_intersection.h | 217 +
.../__algorithm/set_symmetric_difference.h | 109 +
.../include/__cxx03/__algorithm/set_union.h | 105 +
.../include/__cxx03/__algorithm/shift_left.h | 59 +
.../include/__cxx03/__algorithm/shift_right.h | 105 +
libcxx/include/__cxx03/__algorithm/shuffle.h | 167 +
.../include/__cxx03/__algorithm/sift_down.h | 118 +
.../include/__cxx03/__algorithm/simd_utils.h | 164 +
libcxx/include/__cxx03/__algorithm/sort.h | 1016 +++
.../include/__cxx03/__algorithm/sort_heap.h | 63 +
.../__cxx03/__algorithm/stable_partition.h | 307 +
.../include/__cxx03/__algorithm/stable_sort.h | 273 +
.../include/__cxx03/__algorithm/swap_ranges.h | 62 +
.../__algorithm/three_way_comp_ref_type.h | 74 +
.../include/__cxx03/__algorithm/transform.h | 42 +
.../uniform_random_bit_generator_adaptor.h | 58 +
libcxx/include/__cxx03/__algorithm/unique.h | 64 +
.../include/__cxx03/__algorithm/unique_copy.h | 127 +
.../include/__cxx03/__algorithm/unwrap_iter.h | 85 +
.../__cxx03/__algorithm/unwrap_range.h | 99 +
.../include/__cxx03/__algorithm/upper_bound.h | 68 +
libcxx/include/__cxx03/__assert | 118 +
libcxx/include/__cxx03/__atomic/aliases.h | 110 +
libcxx/include/__cxx03/__atomic/atomic.h | 622 ++
libcxx/include/__cxx03/__atomic/atomic_base.h | 221 +
libcxx/include/__cxx03/__atomic/atomic_flag.h | 189 +
libcxx/include/__cxx03/__atomic/atomic_init.h | 25 +
.../__cxx03/__atomic/atomic_lock_free.h | 48 +
libcxx/include/__cxx03/__atomic/atomic_ref.h | 378 ++
libcxx/include/__cxx03/__atomic/atomic_sync.h | 205 +
.../__cxx03/__atomic/check_memory_order.h | 34 +
.../include/__cxx03/__atomic/contention_t.h | 32 +
.../__cxx03/__atomic/cxx_atomic_impl.h | 510 ++
libcxx/include/__cxx03/__atomic/fence.h | 28 +
.../__cxx03/__atomic/is_always_lock_free.h | 28 +
.../__cxx03/__atomic/kill_dependency.h | 27 +
.../include/__cxx03/__atomic/memory_order.h | 65 +
.../include/__cxx03/__atomic/to_gcc_order.h | 54 +
libcxx/include/__cxx03/__bit/bit_cast.h | 44 +
libcxx/include/__cxx03/__bit/bit_ceil.h | 54 +
libcxx/include/__cxx03/__bit/bit_floor.h | 34 +
libcxx/include/__cxx03/__bit/bit_log2.h | 34 +
libcxx/include/__cxx03/__bit/bit_width.h | 33 +
libcxx/include/__cxx03/__bit/blsr.h | 34 +
libcxx/include/__cxx03/__bit/byteswap.h | 53 +
libcxx/include/__cxx03/__bit/countl.h | 113 +
libcxx/include/__cxx03/__bit/countr.h | 84 +
libcxx/include/__cxx03/__bit/endian.h | 38 +
libcxx/include/__cxx03/__bit/has_single_bit.h | 37 +
libcxx/include/__cxx03/__bit/invert_if.h | 30 +
libcxx/include/__cxx03/__bit/popcount.h | 71 +
libcxx/include/__cxx03/__bit/rotate.h | 72 +
libcxx/include/__cxx03/__bit_reference | 1024 +++
.../include/__cxx03/__charconv/chars_format.h | 61 +
.../__cxx03/__charconv/from_chars_integral.h | 240 +
.../__cxx03/__charconv/from_chars_result.h | 39 +
libcxx/include/__cxx03/__charconv/tables.h | 163 +
libcxx/include/__cxx03/__charconv/to_chars.h | 25 +
.../__cxx03/__charconv/to_chars_base_10.h | 188 +
.../__charconv/to_chars_floating_point.h | 55 +
.../__cxx03/__charconv/to_chars_integral.h | 327 +
.../__cxx03/__charconv/to_chars_result.h | 39 +
libcxx/include/__cxx03/__charconv/traits.h | 200 +
libcxx/include/__cxx03/__chrono/calendar.h | 44 +
libcxx/include/__cxx03/__chrono/concepts.h | 36 +
.../__cxx03/__chrono/convert_to_timespec.h | 51 +
.../include/__cxx03/__chrono/convert_to_tm.h | 202 +
libcxx/include/__cxx03/__chrono/day.h | 99 +
libcxx/include/__cxx03/__chrono/duration.h | 550 ++
libcxx/include/__cxx03/__chrono/exception.h | 135 +
libcxx/include/__cxx03/__chrono/file_clock.h | 80 +
libcxx/include/__cxx03/__chrono/formatter.h | 990 +++
libcxx/include/__cxx03/__chrono/hh_mm_ss.h | 112 +
.../__cxx03/__chrono/high_resolution_clock.h | 35 +
libcxx/include/__cxx03/__chrono/leap_second.h | 126 +
libcxx/include/__cxx03/__chrono/literals.h | 45 +
libcxx/include/__cxx03/__chrono/local_info.h | 50 +
libcxx/include/__cxx03/__chrono/month.h | 115 +
.../include/__cxx03/__chrono/month_weekday.h | 105 +
libcxx/include/__cxx03/__chrono/monthday.h | 133 +
libcxx/include/__cxx03/__chrono/ostream.h | 322 +
.../__cxx03/__chrono/parser_std_format_spec.h | 416 ++
.../__cxx03/__chrono/statically_widen.h | 52 +
.../include/__cxx03/__chrono/steady_clock.h | 42 +
libcxx/include/__cxx03/__chrono/sys_info.h | 51 +
.../include/__cxx03/__chrono/system_clock.h | 52 +
libcxx/include/__cxx03/__chrono/time_point.h | 220 +
libcxx/include/__cxx03/__chrono/time_zone.h | 182 +
.../include/__cxx03/__chrono/time_zone_link.h | 79 +
libcxx/include/__cxx03/__chrono/tzdb.h | 94 +
libcxx/include/__cxx03/__chrono/tzdb_list.h | 108 +
libcxx/include/__cxx03/__chrono/weekday.h | 186 +
libcxx/include/__cxx03/__chrono/year.h | 118 +
libcxx/include/__cxx03/__chrono/year_month.h | 123 +
.../include/__cxx03/__chrono/year_month_day.h | 337 +
.../__cxx03/__chrono/year_month_weekday.h | 287 +
libcxx/include/__cxx03/__chrono/zoned_time.h | 227 +
.../__compare/common_comparison_category.h | 86 +
.../compare_partial_order_fallback.h | 76 +
.../__compare/compare_strong_order_fallback.h | 73 +
.../__cxx03/__compare/compare_three_way.h | 40 +
.../__compare/compare_three_way_result.h | 45 +
.../__compare/compare_weak_order_fallback.h | 73 +
libcxx/include/__cxx03/__compare/is_eq.h | 34 +
libcxx/include/__cxx03/__compare/ordering.h | 278 +
.../include/__cxx03/__compare/partial_order.h | 77 +
.../include/__cxx03/__compare/strong_order.h | 143 +
.../__cxx03/__compare/synth_three_way.h | 52 +
.../__cxx03/__compare/three_way_comparable.h | 55 +
libcxx/include/__cxx03/__compare/weak_order.h | 105 +
.../include/__cxx03/__concepts/arithmetic.h | 56 +
.../include/__cxx03/__concepts/assignable.h | 41 +
.../__cxx03/__concepts/boolean_testable.h | 38 +
.../__cxx03/__concepts/class_or_enum.h | 35 +
.../__concepts/common_reference_with.h | 36 +
.../include/__cxx03/__concepts/common_with.h | 52 +
.../__cxx03/__concepts/constructible.h | 55 +
.../__cxx03/__concepts/convertible_to.h | 33 +
libcxx/include/__cxx03/__concepts/copyable.h | 41 +
.../include/__cxx03/__concepts/derived_from.h | 33 +
.../include/__cxx03/__concepts/destructible.h | 32 +
.../__cxx03/__concepts/different_from.h | 31 +
.../__cxx03/__concepts/equality_comparable.h | 56 +
libcxx/include/__cxx03/__concepts/invocable.h | 40 +
libcxx/include/__cxx03/__concepts/movable.h | 35 +
libcxx/include/__cxx03/__concepts/predicate.h | 34 +
libcxx/include/__cxx03/__concepts/regular.h | 33 +
libcxx/include/__cxx03/__concepts/relation.h | 43 +
libcxx/include/__cxx03/__concepts/same_as.h | 35 +
.../include/__cxx03/__concepts/semiregular.h | 33 +
libcxx/include/__cxx03/__concepts/swappable.h | 123 +
.../__cxx03/__concepts/totally_ordered.h | 59 +
.../__condition_variable/condition_variable.h | 244 +
libcxx/include/__cxx03/__config | 1228 ++++
libcxx/include/__cxx03/__config_site.in | 56 +
libcxx/include/__cxx03/__configuration/abi.h | 172 +
.../__cxx03/__configuration/availability.h | 400 ++
.../__cxx03/__configuration/compiler.h | 51 +
.../__cxx03/__configuration/language.h | 46 +
.../__cxx03/__configuration/platform.h | 54 +
.../__cxx03/__coroutine/coroutine_handle.h | 176 +
.../__cxx03/__coroutine/coroutine_traits.h | 48 +
.../__coroutine/noop_coroutine_handle.h | 99 +
.../__cxx03/__coroutine/trivial_awaitables.h | 40 +
.../__cxx03/__debug_utils/randomize_range.h | 42 +
.../__cxx03/__debug_utils/sanitizers.h | 104 +
.../strict_weak_ordering_check.h | 77 +
.../include/__cxx03/__exception/exception.h | 94 +
.../__cxx03/__exception/exception_ptr.h | 177 +
.../__cxx03/__exception/nested_exception.h | 99 +
.../include/__cxx03/__exception/operations.h | 41 +
.../include/__cxx03/__exception/terminate.h | 22 +
.../__cxx03/__expected/bad_expected_access.h | 73 +
libcxx/include/__cxx03/__expected/expected.h | 1875 ++++++
libcxx/include/__cxx03/__expected/unexpect.h | 32 +
.../include/__cxx03/__expected/unexpected.h | 127 +
.../__cxx03/__filesystem/copy_options.h | 69 +
.../__cxx03/__filesystem/directory_entry.h | 435 ++
.../__cxx03/__filesystem/directory_iterator.h | 151 +
.../__cxx03/__filesystem/directory_options.h | 57 +
.../__cxx03/__filesystem/file_status.h | 67 +
.../__cxx03/__filesystem/file_time_type.h | 31 +
.../include/__cxx03/__filesystem/file_type.h | 42 +
.../__cxx03/__filesystem/filesystem_error.h | 88 +
.../include/__cxx03/__filesystem/operations.h | 310 +
libcxx/include/__cxx03/__filesystem/path.h | 931 +++
.../__cxx03/__filesystem/path_iterator.h | 115 +
.../__cxx03/__filesystem/perm_options.h | 57 +
libcxx/include/__cxx03/__filesystem/perms.h | 80 +
.../recursive_directory_iterator.h | 164 +
.../include/__cxx03/__filesystem/space_info.h | 38 +
libcxx/include/__cxx03/__filesystem/u8path.h | 100 +
libcxx/include/__cxx03/__format/buffer.h | 655 ++
libcxx/include/__cxx03/__format/concepts.h | 83 +
.../__cxx03/__format/container_adaptor.h | 73 +
.../__cxx03/__format/enable_insertable.h | 35 +
.../__cxx03/__format/escaped_output_table.h | 863 +++
.../extended_grapheme_cluster_table.h | 1663 +++++
libcxx/include/__cxx03/__format/format_arg.h | 401 ++
.../__cxx03/__format/format_arg_store.h | 266 +
libcxx/include/__cxx03/__format/format_args.h | 78 +
.../include/__cxx03/__format/format_context.h | 220 +
.../include/__cxx03/__format/format_error.h | 50 +
.../__cxx03/__format/format_functions.h | 680 ++
.../__cxx03/__format/format_parse_context.h | 105 +
.../include/__cxx03/__format/format_string.h | 160 +
.../__cxx03/__format/format_to_n_result.h | 35 +
libcxx/include/__cxx03/__format/formatter.h | 53 +
.../include/__cxx03/__format/formatter_bool.h | 76 +
.../include/__cxx03/__format/formatter_char.h | 93 +
.../__format/formatter_floating_point.h | 783 +++
.../__cxx03/__format/formatter_integer.h | 95 +
.../__cxx03/__format/formatter_integral.h | 445 ++
.../__cxx03/__format/formatter_output.h | 335 +
.../__cxx03/__format/formatter_pointer.h | 72 +
.../__cxx03/__format/formatter_string.h | 150 +
.../__cxx03/__format/formatter_tuple.h | 150 +
.../__format/indic_conjunct_break_table.h | 350 +
.../__cxx03/__format/parser_std_format_spec.h | 1172 ++++
.../__format/range_default_formatter.h | 214 +
.../__cxx03/__format/range_formatter.h | 264 +
libcxx/include/__cxx03/__format/unicode.h | 602 ++
.../__cxx03/__format/width_estimation_table.h | 270 +
.../include/__cxx03/__format/write_escaped.h | 242 +
.../__cxx03/__functional/binary_function.h | 54 +
.../__cxx03/__functional/binary_negate.h | 51 +
libcxx/include/__cxx03/__functional/bind.h | 296 +
.../include/__cxx03/__functional/bind_back.h | 83 +
.../include/__cxx03/__functional/bind_front.h | 54 +
.../include/__cxx03/__functional/binder1st.h | 54 +
.../include/__cxx03/__functional/binder2nd.h | 54 +
.../__functional/boyer_moore_searcher.h | 306 +
libcxx/include/__cxx03/__functional/compose.h | 53 +
.../__cxx03/__functional/default_searcher.h | 54 +
.../include/__cxx03/__functional/function.h | 1048 +++
libcxx/include/__cxx03/__functional/hash.h | 542 ++
.../include/__cxx03/__functional/identity.h | 65 +
libcxx/include/__cxx03/__functional/invoke.h | 54 +
.../__cxx03/__functional/is_transparent.h | 34 +
libcxx/include/__cxx03/__functional/mem_fn.h | 54 +
.../__cxx03/__functional/mem_fun_ref.h | 146 +
libcxx/include/__cxx03/__functional/not_fn.h | 53 +
.../include/__cxx03/__functional/operations.h | 541 ++
.../__cxx03/__functional/perfect_forward.h | 104 +
.../__functional/pointer_to_binary_function.h | 44 +
.../__functional/pointer_to_unary_function.h | 44 +
.../__cxx03/__functional/ranges_operations.h | 109 +
.../__cxx03/__functional/reference_wrapper.h | 154 +
.../__cxx03/__functional/unary_function.h | 51 +
.../__cxx03/__functional/unary_negate.h | 48 +
.../__cxx03/__functional/weak_result_type.h | 231 +
libcxx/include/__cxx03/__fwd/array.h | 46 +
libcxx/include/__cxx03/__fwd/bit_reference.h | 25 +
libcxx/include/__cxx03/__fwd/complex.h | 42 +
libcxx/include/__cxx03/__fwd/deque.h | 26 +
libcxx/include/__cxx03/__fwd/format.h | 38 +
libcxx/include/__cxx03/__fwd/fstream.h | 53 +
libcxx/include/__cxx03/__fwd/functional.h | 28 +
libcxx/include/__cxx03/__fwd/ios.h | 43 +
libcxx/include/__cxx03/__fwd/istream.h | 43 +
libcxx/include/__cxx03/__fwd/mdspan.h | 57 +
libcxx/include/__cxx03/__fwd/memory.h | 25 +
.../include/__cxx03/__fwd/memory_resource.h | 27 +
libcxx/include/__cxx03/__fwd/ostream.h | 35 +
libcxx/include/__cxx03/__fwd/pair.h | 45 +
libcxx/include/__cxx03/__fwd/queue.h | 31 +
libcxx/include/__cxx03/__fwd/span.h | 38 +
libcxx/include/__cxx03/__fwd/sstream.h | 58 +
libcxx/include/__cxx03/__fwd/stack.h | 26 +
libcxx/include/__cxx03/__fwd/streambuf.h | 35 +
libcxx/include/__cxx03/__fwd/string.h | 107 +
libcxx/include/__cxx03/__fwd/string_view.h | 50 +
libcxx/include/__cxx03/__fwd/subrange.h | 49 +
libcxx/include/__cxx03/__fwd/tuple.h | 52 +
libcxx/include/__cxx03/__fwd/vector.h | 26 +
libcxx/include/__cxx03/__hash_table | 2044 ++++++
libcxx/include/__cxx03/__ios/fpos.h | 76 +
libcxx/include/__cxx03/__iterator/access.h | 95 +
libcxx/include/__cxx03/__iterator/advance.h | 205 +
.../__cxx03/__iterator/aliasing_iterator.h | 127 +
.../__cxx03/__iterator/back_insert_iterator.h | 85 +
.../include/__cxx03/__iterator/bounded_iter.h | 283 +
.../__cxx03/__iterator/common_iterator.h | 299 +
libcxx/include/__cxx03/__iterator/concepts.h | 257 +
.../__cxx03/__iterator/counted_iterator.h | 289 +
.../__iterator/cpp17_iterator_concepts.h | 190 +
libcxx/include/__cxx03/__iterator/data.h | 49 +
.../__cxx03/__iterator/default_sentinel.h | 30 +
libcxx/include/__cxx03/__iterator/distance.h | 99 +
libcxx/include/__cxx03/__iterator/empty.h | 45 +
.../__cxx03/__iterator/erase_if_container.h | 43 +
.../__iterator/front_insert_iterator.h | 83 +
.../__cxx03/__iterator/incrementable_traits.h | 79 +
.../__iterator/indirectly_comparable.h | 33 +
.../__cxx03/__iterator/insert_iterator.h | 95 +
.../__cxx03/__iterator/istream_iterator.h | 101 +
.../__cxx03/__iterator/istreambuf_iterator.h | 109 +
libcxx/include/__cxx03/__iterator/iter_move.h | 103 +
libcxx/include/__cxx03/__iterator/iter_swap.h | 108 +
libcxx/include/__cxx03/__iterator/iterator.h | 33 +
.../__cxx03/__iterator/iterator_traits.h | 528 ++
.../__cxx03/__iterator/iterator_with_data.h | 105 +
libcxx/include/__cxx03/__iterator/mergeable.h | 42 +
.../__cxx03/__iterator/move_iterator.h | 347 +
.../__cxx03/__iterator/move_sentinel.h | 61 +
libcxx/include/__cxx03/__iterator/next.h | 83 +
.../__cxx03/__iterator/ostream_iterator.h | 75 +
.../__cxx03/__iterator/ostreambuf_iterator.h | 72 +
.../include/__cxx03/__iterator/permutable.h | 34 +
libcxx/include/__cxx03/__iterator/prev.h | 76 +
libcxx/include/__cxx03/__iterator/projected.h | 53 +
.../__iterator/ranges_iterator_traits.h | 40 +
.../__cxx03/__iterator/readable_traits.h | 81 +
.../__cxx03/__iterator/reverse_access.h | 80 +
.../__cxx03/__iterator/reverse_iterator.h | 346 +
.../__cxx03/__iterator/segmented_iterator.h | 79 +
libcxx/include/__cxx03/__iterator/size.h | 59 +
libcxx/include/__cxx03/__iterator/sortable.h | 35 +
.../__cxx03/__iterator/unreachable_sentinel.h | 37 +
libcxx/include/__cxx03/__iterator/wrap_iter.h | 244 +
libcxx/include/__cxx03/__locale | 1513 +++++
.../__cxx03/__locale_dir/locale_base_api.h | 98 +
.../__locale_dir/locale_base_api/android.h | 50 +
.../locale_base_api/bsd_locale_defaults.h | 36 +
.../locale_base_api/bsd_locale_fallbacks.h | 126 +
.../__locale_dir/locale_base_api/fuchsia.h | 18 +
.../__locale_dir/locale_base_api/ibm.h | 108 +
.../locale_base_api/locale_guard.h | 78 +
.../__locale_dir/locale_base_api/musl.h | 31 +
.../__locale_dir/locale_base_api/newlib.h | 12 +
.../__locale_dir/locale_base_api/openbsd.h | 19 +
.../__locale_dir/locale_base_api/win32.h | 235 +
libcxx/include/__cxx03/__math/abs.h | 46 +
libcxx/include/__cxx03/__math/copysign.h | 45 +
.../include/__cxx03/__math/error_functions.h | 60 +
.../__cxx03/__math/exponential_functions.h | 171 +
libcxx/include/__cxx03/__math/fdim.h | 48 +
libcxx/include/__cxx03/__math/fma.h | 55 +
libcxx/include/__cxx03/__math/gamma.h | 62 +
.../__cxx03/__math/hyperbolic_functions.h | 76 +
libcxx/include/__cxx03/__math/hypot.h | 109 +
.../__math/inverse_hyperbolic_functions.h | 76 +
.../__math/inverse_trigonometric_functions.h | 99 +
libcxx/include/__cxx03/__math/logarithms.h | 124 +
libcxx/include/__cxx03/__math/min_max.h | 74 +
libcxx/include/__cxx03/__math/modulo.h | 63 +
libcxx/include/__cxx03/__math/remainder.h | 73 +
libcxx/include/__cxx03/__math/roots.h | 62 +
.../__cxx03/__math/rounding_functions.h | 245 +
.../__cxx03/__math/special_functions.h | 84 +
libcxx/include/__cxx03/__math/traits.h | 188 +
.../__cxx03/__math/trigonometric_functions.h | 76 +
libcxx/include/__cxx03/__mbstate_t.h | 54 +
.../__cxx03/__mdspan/default_accessor.h | 66 +
libcxx/include/__cxx03/__mdspan/extents.h | 532 ++
libcxx/include/__cxx03/__mdspan/layout_left.h | 204 +
.../include/__cxx03/__mdspan/layout_right.h | 201 +
.../include/__cxx03/__mdspan/layout_stride.h | 366 ++
libcxx/include/__cxx03/__mdspan/mdspan.h | 319 +
libcxx/include/__cxx03/__memory/addressof.h | 61 +
libcxx/include/__cxx03/__memory/align.h | 25 +
.../include/__cxx03/__memory/aligned_alloc.h | 64 +
.../__cxx03/__memory/allocate_at_least.h | 48 +
.../__cxx03/__memory/allocation_guard.h | 108 +
libcxx/include/__cxx03/__memory/allocator.h | 268 +
.../__cxx03/__memory/allocator_arg_t.h | 75 +
.../__cxx03/__memory/allocator_destructor.h | 40 +
.../__cxx03/__memory/allocator_traits.h | 424 ++
.../include/__cxx03/__memory/assume_aligned.h | 50 +
libcxx/include/__cxx03/__memory/auto_ptr.h | 92 +
.../__cxx03/__memory/builtin_new_allocator.h | 67 +
.../__cxx03/__memory/compressed_pair.h | 171 +
libcxx/include/__cxx03/__memory/concepts.h | 63 +
.../include/__cxx03/__memory/construct_at.h | 128 +
libcxx/include/__cxx03/__memory/destruct_n.h | 63 +
libcxx/include/__cxx03/__memory/inout_ptr.h | 109 +
libcxx/include/__cxx03/__memory/out_ptr.h | 101 +
.../include/__cxx03/__memory/pointer_traits.h | 307 +
.../__cxx03/__memory/ranges_construct_at.h | 124 +
.../ranges_uninitialized_algorithms.h | 325 +
.../__cxx03/__memory/raw_storage_iterator.h | 87 +
libcxx/include/__cxx03/__memory/shared_ptr.h | 1694 +++++
.../include/__cxx03/__memory/swap_allocator.h | 54 +
libcxx/include/__cxx03/__memory/temp_value.h | 58 +
.../__cxx03/__memory/temporary_buffer.h | 75 +
.../__memory/uninitialized_algorithms.h | 653 ++
libcxx/include/__cxx03/__memory/unique_ptr.h | 693 ++
.../include/__cxx03/__memory/uses_allocator.h | 52 +
.../__memory/uses_allocator_construction.h | 247 +
libcxx/include/__cxx03/__memory/voidify.h | 30 +
.../__memory_resource/memory_resource.h | 88 +
.../monotonic_buffer_resource.h | 122 +
.../__memory_resource/polymorphic_allocator.h | 231 +
.../__cxx03/__memory_resource/pool_options.h | 38 +
.../synchronized_pool_resource.h | 92 +
.../unsynchronized_pool_resource.h | 106 +
libcxx/include/__cxx03/__mutex/lock_guard.h | 48 +
libcxx/include/__cxx03/__mutex/mutex.h | 53 +
libcxx/include/__cxx03/__mutex/once_flag.h | 159 +
libcxx/include/__cxx03/__mutex/tag_types.h | 44 +
libcxx/include/__cxx03/__mutex/unique_lock.h | 177 +
libcxx/include/__cxx03/__node_handle | 209 +
libcxx/include/__cxx03/__numeric/accumulate.h | 53 +
.../__cxx03/__numeric/adjacent_difference.h | 68 +
.../__cxx03/__numeric/exclusive_scan.h | 58 +
libcxx/include/__cxx03/__numeric/gcd_lcm.h | 132 +
.../__cxx03/__numeric/inclusive_scan.h | 59 +
.../include/__cxx03/__numeric/inner_product.h | 58 +
libcxx/include/__cxx03/__numeric/iota.h | 30 +
libcxx/include/__cxx03/__numeric/midpoint.h | 88 +
.../include/__cxx03/__numeric/partial_sum.h | 66 +
libcxx/include/__cxx03/__numeric/pstl.h | 174 +
libcxx/include/__cxx03/__numeric/reduce.h | 53 +
.../__cxx03/__numeric/saturation_arithmetic.h | 145 +
.../__numeric/transform_exclusive_scan.h | 42 +
.../__numeric/transform_inclusive_scan.h | 52 +
.../__cxx03/__numeric/transform_reduce.h | 59 +
.../include/__cxx03/__ostream/basic_ostream.h | 860 +++
libcxx/include/__cxx03/__ostream/print.h | 179 +
libcxx/include/__cxx03/__pstl/backend.h | 35 +
libcxx/include/__cxx03/__pstl/backend_fwd.h | 301 +
.../include/__cxx03/__pstl/backends/default.h | 503 ++
.../__cxx03/__pstl/backends/libdispatch.h | 397 ++
.../include/__cxx03/__pstl/backends/serial.h | 181 +
.../__cxx03/__pstl/backends/std_thread.h | 136 +
.../include/__cxx03/__pstl/cpu_algos/any_of.h | 99 +
.../__cxx03/__pstl/cpu_algos/cpu_traits.h | 86 +
.../include/__cxx03/__pstl/cpu_algos/fill.h | 66 +
.../__cxx03/__pstl/cpu_algos/find_if.h | 137 +
.../__cxx03/__pstl/cpu_algos/for_each.h | 66 +
.../include/__cxx03/__pstl/cpu_algos/merge.h | 85 +
.../__cxx03/__pstl/cpu_algos/stable_sort.h | 47 +
.../__cxx03/__pstl/cpu_algos/transform.h | 153 +
.../__pstl/cpu_algos/transform_reduce.h | 216 +
libcxx/include/__cxx03/__pstl/dispatch.h | 66 +
.../include/__cxx03/__pstl/handle_exception.h | 57 +
.../__cxx03/__random/bernoulli_distribution.h | 123 +
.../__cxx03/__random/binomial_distribution.h | 198 +
.../__cxx03/__random/cauchy_distribution.h | 139 +
.../__random/chi_squared_distribution.h | 125 +
.../__cxx03/__random/clamp_to_integral.h | 59 +
.../__cxx03/__random/default_random_engine.h | 25 +
.../__cxx03/__random/discard_block_engine.h | 172 +
.../__cxx03/__random/discrete_distribution.h | 212 +
.../__random/exponential_distribution.h | 132 +
.../__random/extreme_value_distribution.h | 139 +
.../__cxx03/__random/fisher_f_distribution.h | 138 +
.../__cxx03/__random/gamma_distribution.h | 181 +
.../__cxx03/__random/generate_canonical.h | 51 +
.../__cxx03/__random/geometric_distribution.h | 120 +
.../__random/independent_bits_engine.h | 205 +
.../__cxx03/__random/is_seed_sequence.h | 31 +
libcxx/include/__cxx03/__random/is_valid.h | 94 +
libcxx/include/__cxx03/__random/knuth_b.h | 26 +
.../__random/linear_congruential_engine.h | 387 ++
libcxx/include/__cxx03/__random/log2.h | 66 +
.../__cxx03/__random/lognormal_distribution.h | 126 +
.../__random/mersenne_twister_engine.h | 914 +++
.../__random/negative_binomial_distribution.h | 157 +
.../__cxx03/__random/normal_distribution.h | 176 +
.../piecewise_constant_distribution.h | 302 +
.../__random/piecewise_linear_distribution.h | 315 +
.../__cxx03/__random/poisson_distribution.h | 241 +
.../include/__cxx03/__random/random_device.h | 81 +
libcxx/include/__cxx03/__random/ranlux.h | 31 +
libcxx/include/__cxx03/__random/seed_seq.h | 166 +
.../__cxx03/__random/shuffle_order_engine.h | 230 +
.../__cxx03/__random/student_t_distribution.h | 132 +
.../__random/subtract_with_carry_engine.h | 276 +
.../__random/uniform_int_distribution.h | 264 +
.../__random/uniform_random_bit_generator.h | 44 +
.../__random/uniform_real_distribution.h | 138 +
.../__cxx03/__random/weibull_distribution.h | 132 +
libcxx/include/__cxx03/__ranges/access.h | 210 +
libcxx/include/__cxx03/__ranges/all.h | 78 +
.../include/__cxx03/__ranges/as_rvalue_view.h | 142 +
.../include/__cxx03/__ranges/chunk_by_view.h | 235 +
libcxx/include/__cxx03/__ranges/common_view.h | 142 +
libcxx/include/__cxx03/__ranges/concepts.h | 142 +
.../__ranges/container_compatible_range.h | 33 +
libcxx/include/__cxx03/__ranges/counted.h | 89 +
libcxx/include/__cxx03/__ranges/dangling.h | 42 +
libcxx/include/__cxx03/__ranges/data.h | 102 +
libcxx/include/__cxx03/__ranges/drop_view.h | 329 +
.../__cxx03/__ranges/drop_while_view.h | 136 +
.../include/__cxx03/__ranges/elements_view.h | 418 ++
libcxx/include/__cxx03/__ranges/empty.h | 71 +
libcxx/include/__cxx03/__ranges/empty_view.h | 54 +
.../__cxx03/__ranges/enable_borrowed_range.h | 40 +
libcxx/include/__cxx03/__ranges/enable_view.h | 51 +
libcxx/include/__cxx03/__ranges/filter_view.h | 260 +
libcxx/include/__cxx03/__ranges/from_range.h | 33 +
libcxx/include/__cxx03/__ranges/iota_view.h | 404 ++
.../include/__cxx03/__ranges/istream_view.h | 141 +
libcxx/include/__cxx03/__ranges/join_view.h | 423 ++
.../__cxx03/__ranges/lazy_split_view.h | 441 ++
libcxx/include/__cxx03/__ranges/movable_box.h | 247 +
.../__cxx03/__ranges/non_propagating_cache.h | 103 +
libcxx/include/__cxx03/__ranges/owning_view.h | 116 +
.../include/__cxx03/__ranges/range_adaptor.h | 101 +
libcxx/include/__cxx03/__ranges/rbegin.h | 120 +
libcxx/include/__cxx03/__ranges/ref_view.h | 89 +
libcxx/include/__cxx03/__ranges/rend.h | 123 +
libcxx/include/__cxx03/__ranges/repeat_view.h | 266 +
.../include/__cxx03/__ranges/reverse_view.h | 203 +
libcxx/include/__cxx03/__ranges/single_view.h | 111 +
libcxx/include/__cxx03/__ranges/size.h | 137 +
libcxx/include/__cxx03/__ranges/split_view.h | 232 +
libcxx/include/__cxx03/__ranges/subrange.h | 273 +
libcxx/include/__cxx03/__ranges/take_view.h | 369 ++
.../__cxx03/__ranges/take_while_view.h | 170 +
libcxx/include/__cxx03/__ranges/to.h | 245 +
.../include/__cxx03/__ranges/transform_view.h | 417 ++
.../include/__cxx03/__ranges/view_interface.h | 170 +
libcxx/include/__cxx03/__ranges/views.h | 35 +
libcxx/include/__cxx03/__ranges/zip_view.h | 516 ++
libcxx/include/__cxx03/__split_buffer | 585 ++
libcxx/include/__cxx03/__std_clang_module | 215 +
libcxx/include/__cxx03/__std_mbstate_t.h | 29 +
.../__cxx03/__stop_token/atomic_unique_lock.h | 140 +
.../__stop_token/intrusive_list_view.h | 85 +
.../__stop_token/intrusive_shared_ptr.h | 134 +
.../__cxx03/__stop_token/stop_callback.h | 102 +
.../__cxx03/__stop_token/stop_source.h | 91 +
.../include/__cxx03/__stop_token/stop_state.h | 236 +
.../include/__cxx03/__stop_token/stop_token.h | 63 +
libcxx/include/__cxx03/__string/char_traits.h | 543 ++
.../__cxx03/__string/constexpr_c_functions.h | 234 +
.../__cxx03/__string/extern_template_lists.h | 133 +
.../__cxx03/__support/ibm/gettod_zos.h | 52 +
.../__cxx03/__support/ibm/locale_mgmt_zos.h | 53 +
.../include/__cxx03/__support/ibm/nanosleep.h | 55 +
.../__support/xlocale/__nop_locale_mgmt.h | 35 +
.../__support/xlocale/__posix_l_fallback.h | 107 +
.../__support/xlocale/__strtonum_fallback.h | 45 +
libcxx/include/__cxx03/__system_error/errc.h | 266 +
.../__cxx03/__system_error/error_category.h | 75 +
.../__cxx03/__system_error/error_code.h | 143 +
.../__cxx03/__system_error/error_condition.h | 130 +
.../__cxx03/__system_error/system_error.h | 54 +
libcxx/include/__cxx03/__thread/formatter.h | 80 +
libcxx/include/__cxx03/__thread/id.h | 121 +
libcxx/include/__cxx03/__thread/jthread.h | 134 +
.../__cxx03/__thread/poll_with_backoff.h | 67 +
libcxx/include/__cxx03/__thread/support.h | 123 +
libcxx/include/__cxx03/__thread/support/c11.h | 191 +
.../__cxx03/__thread/support/external.h | 21 +
.../__cxx03/__thread/support/pthread.h | 221 +
.../__cxx03/__thread/support/windows.h | 133 +
libcxx/include/__cxx03/__thread/this_thread.h | 74 +
libcxx/include/__cxx03/__thread/thread.h | 258 +
.../__cxx03/__thread/timed_backoff_policy.h | 44 +
libcxx/include/__cxx03/__tree | 2299 +++++++
libcxx/include/__cxx03/__tuple/find_index.h | 62 +
libcxx/include/__cxx03/__tuple/ignore.h | 39 +
.../__cxx03/__tuple/make_tuple_types.h | 80 +
.../include/__cxx03/__tuple/sfinae_helpers.h | 142 +
.../include/__cxx03/__tuple/tuple_element.h | 58 +
.../include/__cxx03/__tuple/tuple_indices.h | 37 +
libcxx/include/__cxx03/__tuple/tuple_like.h | 42 +
.../include/__cxx03/__tuple/tuple_like_ext.h | 52 +
.../__cxx03/__tuple/tuple_like_no_subrange.h | 61 +
libcxx/include/__cxx03/__tuple/tuple_size.h | 75 +
libcxx/include/__cxx03/__tuple/tuple_types.h | 25 +
.../include/__cxx03/__type_traits/add_const.h | 32 +
libcxx/include/__cxx03/__type_traits/add_cv.h | 32 +
.../__type_traits/add_lvalue_reference.h | 54 +
.../__cxx03/__type_traits/add_pointer.h | 55 +
.../__type_traits/add_rvalue_reference.h | 54 +
.../__cxx03/__type_traits/add_volatile.h | 32 +
.../__cxx03/__type_traits/aligned_storage.h | 138 +
.../__cxx03/__type_traits/aligned_union.h | 51 +
.../__cxx03/__type_traits/alignment_of.h | 32 +
.../__cxx03/__type_traits/can_extract_key.h | 53 +
.../__cxx03/__type_traits/common_reference.h | 193 +
.../__cxx03/__type_traits/common_type.h | 102 +
.../__cxx03/__type_traits/conditional.h | 58 +
.../__cxx03/__type_traits/conjunction.h | 65 +
.../include/__cxx03/__type_traits/copy_cv.h | 51 +
.../__cxx03/__type_traits/copy_cvref.h | 43 +
.../__cxx03/__type_traits/datasizeof.h | 65 +
libcxx/include/__cxx03/__type_traits/decay.h | 73 +
.../__cxx03/__type_traits/dependent_type.h | 25 +
.../__cxx03/__type_traits/desugars_to.h | 40 +
.../__cxx03/__type_traits/disjunction.h | 58 +
.../include/__cxx03/__type_traits/enable_if.h | 37 +
libcxx/include/__cxx03/__type_traits/extent.h | 54 +
.../has_unique_object_representation.h | 40 +
.../__type_traits/has_virtual_destructor.h | 31 +
.../__cxx03/__type_traits/integral_constant.h | 47 +
libcxx/include/__cxx03/__type_traits/invoke.h | 270 +
.../__cxx03/__type_traits/is_abstract.h | 31 +
.../__cxx03/__type_traits/is_aggregate.h | 33 +
.../__cxx03/__type_traits/is_allocator.h | 34 +
.../__type_traits/is_always_bitcastable.h | 85 +
.../__cxx03/__type_traits/is_arithmetic.h | 34 +
.../include/__cxx03/__type_traits/is_array.h | 51 +
.../__cxx03/__type_traits/is_assignable.h | 52 +
.../__cxx03/__type_traits/is_base_of.h | 31 +
.../__cxx03/__type_traits/is_bounded_array.h | 41 +
.../__cxx03/__type_traits/is_callable.h | 32 +
.../__cxx03/__type_traits/is_char_like_type.h | 28 +
.../include/__cxx03/__type_traits/is_class.h | 31 +
.../__cxx03/__type_traits/is_compound.h | 46 +
.../include/__cxx03/__type_traits/is_const.h | 47 +
.../__type_traits/is_constant_evaluated.h | 32 +
.../__cxx03/__type_traits/is_constructible.h | 59 +
.../__cxx03/__type_traits/is_convertible.h | 31 +
.../__type_traits/is_core_convertible.h | 35 +
.../__cxx03/__type_traits/is_destructible.h | 97 +
.../include/__cxx03/__type_traits/is_empty.h | 31 +
.../include/__cxx03/__type_traits/is_enum.h | 41 +
.../__type_traits/is_equality_comparable.h | 88 +
.../__type_traits/is_execution_policy.h | 59 +
.../include/__cxx03/__type_traits/is_final.h | 36 +
.../__cxx03/__type_traits/is_floating_point.h | 39 +
.../__cxx03/__type_traits/is_function.h | 31 +
.../__cxx03/__type_traits/is_fundamental.h | 48 +
.../is_implicitly_default_constructible.h | 46 +
.../__cxx03/__type_traits/is_integral.h | 74 +
.../__cxx03/__type_traits/is_literal_type.h | 34 +
.../__cxx03/__type_traits/is_member_pointer.h | 43 +
.../__type_traits/is_nothrow_assignable.h | 56 +
.../__type_traits/is_nothrow_constructible.h | 61 +
.../__type_traits/is_nothrow_convertible.h | 62 +
.../__type_traits/is_nothrow_destructible.h | 63 +
.../__cxx03/__type_traits/is_null_pointer.h | 37 +
.../include/__cxx03/__type_traits/is_object.h | 31 +
libcxx/include/__cxx03/__type_traits/is_pod.h | 31 +
.../__cxx03/__type_traits/is_pointer.h | 65 +
.../__cxx03/__type_traits/is_polymorphic.h | 31 +
.../__type_traits/is_primary_template.h | 31 +
.../__cxx03/__type_traits/is_reference.h | 68 +
.../__type_traits/is_reference_wrapper.h | 32 +
.../__cxx03/__type_traits/is_referenceable.h | 41 +
.../include/__cxx03/__type_traits/is_same.h | 44 +
.../include/__cxx03/__type_traits/is_scalar.h | 69 +
.../include/__cxx03/__type_traits/is_signed.h | 59 +
.../__cxx03/__type_traits/is_signed_integer.h | 35 +
.../__cxx03/__type_traits/is_specialization.h | 45 +
.../__type_traits/is_standard_layout.h | 31 +
.../__cxx03/__type_traits/is_swappable.h | 104 +
.../__cxx03/__type_traits/is_trivial.h | 31 +
.../__type_traits/is_trivially_assignable.h | 56 +
.../is_trivially_constructible.h | 61 +
.../__type_traits/is_trivially_copyable.h | 37 +
.../__type_traits/is_trivially_destructible.h | 47 +
...s_trivially_lexicographically_comparable.h | 53 +
.../__type_traits/is_trivially_relocatable.h | 42 +
.../__type_traits/is_unbounded_array.h | 40 +
.../include/__cxx03/__type_traits/is_union.h | 31 +
.../__cxx03/__type_traits/is_unsigned.h | 59 +
.../__type_traits/is_unsigned_integer.h | 35 +
.../__type_traits/is_valid_expansion.h | 31 +
.../include/__cxx03/__type_traits/is_void.h | 31 +
.../__cxx03/__type_traits/is_volatile.h | 47 +
libcxx/include/__cxx03/__type_traits/lazy.h | 25 +
.../__type_traits/make_32_64_or_128_bit.h | 49 +
.../__type_traits/make_const_lvalue_ref.h | 26 +
.../__cxx03/__type_traits/make_signed.h | 89 +
.../__cxx03/__type_traits/make_unsigned.h | 101 +
.../__cxx03/__type_traits/maybe_const.h | 26 +
libcxx/include/__cxx03/__type_traits/nat.h | 31 +
.../include/__cxx03/__type_traits/negation.h | 33 +
.../noexcept_move_assign_container.h | 37 +
.../include/__cxx03/__type_traits/promote.h | 128 +
libcxx/include/__cxx03/__type_traits/rank.h | 46 +
.../__type_traits/remove_all_extents.h | 54 +
.../__cxx03/__type_traits/remove_const.h | 49 +
.../__cxx03/__type_traits/remove_const_ref.h | 27 +
.../include/__cxx03/__type_traits/remove_cv.h | 47 +
.../__cxx03/__type_traits/remove_cvref.h | 46 +
.../__cxx03/__type_traits/remove_extent.h | 54 +
.../__cxx03/__type_traits/remove_pointer.h | 53 +
.../__cxx03/__type_traits/remove_reference.h | 47 +
.../__cxx03/__type_traits/remove_volatile.h | 49 +
.../include/__cxx03/__type_traits/result_of.h | 38 +
.../__cxx03/__type_traits/strip_signature.h | 81 +
.../__cxx03/__type_traits/type_identity.h | 39 +
.../include/__cxx03/__type_traits/type_list.h | 42 +
.../__cxx03/__type_traits/underlying_type.h | 42 +
.../__cxx03/__type_traits/unwrap_ref.h | 58 +
libcxx/include/__cxx03/__type_traits/void_t.h | 30 +
libcxx/include/__cxx03/__undef_macros | 28 +
libcxx/include/__cxx03/__utility/as_const.h | 35 +
libcxx/include/__cxx03/__utility/as_lvalue.h | 37 +
libcxx/include/__cxx03/__utility/auto_cast.h | 22 +
libcxx/include/__cxx03/__utility/cmp.h | 81 +
.../__cxx03/__utility/convert_to_integral.h | 68 +
libcxx/include/__cxx03/__utility/declval.h | 38 +
libcxx/include/__cxx03/__utility/empty.h | 24 +
.../__cxx03/__utility/exception_guard.h | 144 +
libcxx/include/__cxx03/__utility/exchange.h | 41 +
libcxx/include/__cxx03/__utility/forward.h | 38 +
.../include/__cxx03/__utility/forward_like.h | 46 +
libcxx/include/__cxx03/__utility/in_place.h | 63 +
.../__cxx03/__utility/integer_sequence.h | 90 +
.../__cxx03/__utility/is_pointer_in_range.h | 62 +
.../__cxx03/__utility/is_valid_range.h | 37 +
libcxx/include/__cxx03/__utility/move.h | 49 +
libcxx/include/__cxx03/__utility/no_destroy.h | 54 +
libcxx/include/__cxx03/__utility/pair.h | 718 ++
.../__cxx03/__utility/piecewise_construct.h | 32 +
.../include/__cxx03/__utility/priority_tag.h | 28 +
.../__utility/private_constructor_tag.h | 28 +
libcxx/include/__cxx03/__utility/rel_ops.h | 46 +
.../include/__cxx03/__utility/small_buffer.h | 99 +
libcxx/include/__cxx03/__utility/swap.h | 59 +
.../include/__cxx03/__utility/to_underlying.h | 38 +
.../include/__cxx03/__utility/unreachable.h | 34 +
libcxx/include/__cxx03/__variant/monostate.h | 64 +
libcxx/include/__cxx03/__verbose_abort | 52 +
libcxx/include/__cxx03/algorithm | 2049 ++++++
libcxx/include/__cxx03/any | 614 ++
libcxx/include/__cxx03/array | 515 ++
libcxx/include/__cxx03/atomic | 632 ++
libcxx/include/__cxx03/barrier | 308 +
libcxx/include/__cxx03/bit | 101 +
libcxx/include/__cxx03/bitset | 969 +++
libcxx/include/__cxx03/cassert | 31 +
libcxx/include/__cxx03/ccomplex | 26 +
libcxx/include/__cxx03/cctype | 127 +
libcxx/include/__cxx03/cerrno | 48 +
libcxx/include/__cxx03/cfenv | 90 +
libcxx/include/__cxx03/cfloat | 88 +
libcxx/include/__cxx03/charconv | 115 +
libcxx/include/__cxx03/chrono | 1022 +++
libcxx/include/__cxx03/cinttypes | 270 +
libcxx/include/__cxx03/ciso646 | 24 +
libcxx/include/__cxx03/climits | 48 +
libcxx/include/__cxx03/clocale | 61 +
libcxx/include/__cxx03/cmath | 646 ++
libcxx/include/__cxx03/codecvt | 597 ++
libcxx/include/__cxx03/compare | 178 +
libcxx/include/__cxx03/complex | 1480 +++++
libcxx/include/__cxx03/complex.h | 32 +
libcxx/include/__cxx03/concepts | 173 +
libcxx/include/__cxx03/condition_variable | 369 ++
libcxx/include/__cxx03/coroutine | 67 +
libcxx/include/__cxx03/csetjmp | 54 +
libcxx/include/__cxx03/csignal | 64 +
libcxx/include/__cxx03/cstdarg | 54 +
libcxx/include/__cxx03/cstdbool | 31 +
libcxx/include/__cxx03/cstddef | 133 +
libcxx/include/__cxx03/cstdint | 199 +
libcxx/include/__cxx03/cstdio | 174 +
libcxx/include/__cxx03/cstdlib | 154 +
libcxx/include/__cxx03/cstring | 104 +
libcxx/include/__cxx03/ctgmath | 28 +
libcxx/include/__cxx03/ctime | 86 +
libcxx/include/__cxx03/ctype.h | 61 +
libcxx/include/__cxx03/cuchar | 75 +
libcxx/include/__cxx03/cwchar | 261 +
libcxx/include/__cxx03/cwctype | 97 +
libcxx/include/__cxx03/deque | 2621 ++++++++
libcxx/include/__cxx03/errno.h | 399 ++
libcxx/include/__cxx03/exception | 96 +
libcxx/include/__cxx03/execution | 149 +
libcxx/include/__cxx03/expected | 62 +
libcxx/include/__cxx03/experimental/__config | 45 +
.../__cxx03/experimental/__simd/aligned_tag.h | 75 +
.../__cxx03/experimental/__simd/declaration.h | 81 +
.../__cxx03/experimental/__simd/reference.h | 105 +
.../__cxx03/experimental/__simd/scalar.h | 87 +
.../__cxx03/experimental/__simd/simd.h | 102 +
.../__cxx03/experimental/__simd/simd_mask.h | 90 +
.../__cxx03/experimental/__simd/traits.h | 75 +
.../__cxx03/experimental/__simd/utility.h | 103 +
.../__cxx03/experimental/__simd/vec_ext.h | 119 +
libcxx/include/__cxx03/experimental/iterator | 127 +
libcxx/include/__cxx03/experimental/memory | 198 +
.../__cxx03/experimental/propagate_const | 490 ++
libcxx/include/__cxx03/experimental/simd | 88 +
.../include/__cxx03/experimental/type_traits | 153 +
libcxx/include/__cxx03/experimental/utility | 46 +
libcxx/include/__cxx03/ext/__hash | 85 +
libcxx/include/__cxx03/ext/hash_map | 872 +++
libcxx/include/__cxx03/ext/hash_set | 584 ++
libcxx/include/__cxx03/fenv.h | 114 +
libcxx/include/__cxx03/filesystem | 577 ++
libcxx/include/__cxx03/float.h | 95 +
libcxx/include/__cxx03/format | 257 +
libcxx/include/__cxx03/forward_list | 1575 +++++
libcxx/include/__cxx03/fstream | 1572 +++++
libcxx/include/__cxx03/functional | 598 ++
libcxx/include/__cxx03/future | 2062 ++++++
libcxx/include/__cxx03/initializer_list | 98 +
libcxx/include/__cxx03/inttypes.h | 264 +
libcxx/include/__cxx03/iomanip | 542 ++
libcxx/include/__cxx03/ios | 889 +++
libcxx/include/__cxx03/iosfwd | 186 +
libcxx/include/__cxx03/iostream | 67 +
libcxx/include/__cxx03/istream | 1373 ++++
libcxx/include/__cxx03/iterator | 754 +++
libcxx/include/__cxx03/latch | 129 +
libcxx/include/__cxx03/limits | 584 ++
libcxx/include/__cxx03/list | 1743 +++++
libcxx/include/__cxx03/locale | 3767 +++++++++++
libcxx/include/__cxx03/locale.h | 46 +
libcxx/include/__cxx03/map | 2181 ++++++
libcxx/include/__cxx03/math.h | 520 ++
libcxx/include/__cxx03/mdspan | 438 ++
libcxx/include/__cxx03/memory | 998 +++
libcxx/include/__cxx03/memory_resource | 83 +
libcxx/include/__cxx03/module.modulemap | 2136 ++++++
libcxx/include/__cxx03/mutex | 516 ++
libcxx/include/__cxx03/new | 362 +
libcxx/include/__cxx03/numbers | 164 +
libcxx/include/__cxx03/numeric | 207 +
libcxx/include/__cxx03/optional | 1304 ++++
libcxx/include/__cxx03/ostream | 202 +
libcxx/include/__cxx03/print | 402 ++
libcxx/include/__cxx03/queue | 956 +++
libcxx/include/__cxx03/random | 1742 +++++
libcxx/include/__cxx03/ranges | 463 ++
libcxx/include/__cxx03/ratio | 517 ++
libcxx/include/__cxx03/regex | 5836 +++++++++++++++++
libcxx/include/__cxx03/scoped_allocator | 573 ++
libcxx/include/__cxx03/semaphore | 188 +
libcxx/include/__cxx03/set | 1501 +++++
libcxx/include/__cxx03/shared_mutex | 464 ++
libcxx/include/__cxx03/source_location | 85 +
libcxx/include/__cxx03/span | 636 ++
libcxx/include/__cxx03/sstream | 1276 ++++
libcxx/include/__cxx03/stack | 379 ++
libcxx/include/__cxx03/stdatomic.h | 235 +
libcxx/include/__cxx03/stdbool.h | 40 +
libcxx/include/__cxx03/stddef.h | 44 +
libcxx/include/__cxx03/stdexcept | 286 +
libcxx/include/__cxx03/stdint.h | 127 +
libcxx/include/__cxx03/stdio.h | 123 +
libcxx/include/__cxx03/stdlib.h | 151 +
libcxx/include/__cxx03/stop_token | 56 +
libcxx/include/__cxx03/streambuf | 445 ++
libcxx/include/__cxx03/string | 4352 ++++++++++++
libcxx/include/__cxx03/string.h | 110 +
libcxx/include/__cxx03/string_view | 948 +++
libcxx/include/__cxx03/strstream | 351 +
libcxx/include/__cxx03/syncstream | 512 ++
libcxx/include/__cxx03/system_error | 171 +
libcxx/include/__cxx03/tgmath.h | 34 +
libcxx/include/__cxx03/thread | 130 +
libcxx/include/__cxx03/tuple | 1419 ++++
libcxx/include/__cxx03/type_traits | 523 ++
libcxx/include/__cxx03/typeindex | 106 +
libcxx/include/__cxx03/typeinfo | 389 ++
libcxx/include/__cxx03/uchar.h | 56 +
libcxx/include/__cxx03/unordered_map | 2541 +++++++
libcxx/include/__cxx03/unordered_set | 1811 +++++
libcxx/include/__cxx03/utility | 309 +
libcxx/include/__cxx03/valarray | 3364 ++++++++++
libcxx/include/__cxx03/variant | 1650 +++++
libcxx/include/__cxx03/vector | 3031 +++++++++
libcxx/include/__cxx03/version | 566 ++
libcxx/include/__cxx03/wchar.h | 211 +
libcxx/include/__cxx03/wctype.h | 95 +
1019 files changed, 199795 insertions(+)
create mode 100644 libcxx/include/__cxx03/CMakeLists.txt
create mode 100644 libcxx/include/__cxx03/__algorithm/adjacent_find.h
create mode 100644 libcxx/include/__cxx03/__algorithm/all_of.h
create mode 100644 libcxx/include/__cxx03/__algorithm/any_of.h
create mode 100644 libcxx/include/__cxx03/__algorithm/binary_search.h
create mode 100644 libcxx/include/__cxx03/__algorithm/clamp.h
create mode 100644 libcxx/include/__cxx03/__algorithm/comp.h
create mode 100644 libcxx/include/__cxx03/__algorithm/comp_ref_type.h
create mode 100644 libcxx/include/__cxx03/__algorithm/copy.h
create mode 100644 libcxx/include/__cxx03/__algorithm/copy_backward.h
create mode 100644 libcxx/include/__cxx03/__algorithm/copy_if.h
create mode 100644 libcxx/include/__cxx03/__algorithm/copy_move_common.h
create mode 100644 libcxx/include/__cxx03/__algorithm/copy_n.h
create mode 100644 libcxx/include/__cxx03/__algorithm/count.h
create mode 100644 libcxx/include/__cxx03/__algorithm/count_if.h
create mode 100644 libcxx/include/__cxx03/__algorithm/equal.h
create mode 100644 libcxx/include/__cxx03/__algorithm/equal_range.h
create mode 100644 libcxx/include/__cxx03/__algorithm/fill.h
create mode 100644 libcxx/include/__cxx03/__algorithm/fill_n.h
create mode 100644 libcxx/include/__cxx03/__algorithm/find.h
create mode 100644 libcxx/include/__cxx03/__algorithm/find_end.h
create mode 100644 libcxx/include/__cxx03/__algorithm/find_first_of.h
create mode 100644 libcxx/include/__cxx03/__algorithm/find_if.h
create mode 100644 libcxx/include/__cxx03/__algorithm/find_if_not.h
create mode 100644 libcxx/include/__cxx03/__algorithm/find_segment_if.h
create mode 100644 libcxx/include/__cxx03/__algorithm/fold.h
create mode 100644 libcxx/include/__cxx03/__algorithm/for_each.h
create mode 100644 libcxx/include/__cxx03/__algorithm/for_each_n.h
create mode 100644 libcxx/include/__cxx03/__algorithm/for_each_segment.h
create mode 100644 libcxx/include/__cxx03/__algorithm/generate.h
create mode 100644 libcxx/include/__cxx03/__algorithm/generate_n.h
create mode 100644 libcxx/include/__cxx03/__algorithm/half_positive.h
create mode 100644 libcxx/include/__cxx03/__algorithm/in_found_result.h
create mode 100644 libcxx/include/__cxx03/__algorithm/in_fun_result.h
create mode 100644 libcxx/include/__cxx03/__algorithm/in_in_out_result.h
create mode 100644 libcxx/include/__cxx03/__algorithm/in_in_result.h
create mode 100644 libcxx/include/__cxx03/__algorithm/in_out_out_result.h
create mode 100644 libcxx/include/__cxx03/__algorithm/in_out_result.h
create mode 100644 libcxx/include/__cxx03/__algorithm/includes.h
create mode 100644 libcxx/include/__cxx03/__algorithm/inplace_merge.h
create mode 100644 libcxx/include/__cxx03/__algorithm/is_heap.h
create mode 100644 libcxx/include/__cxx03/__algorithm/is_heap_until.h
create mode 100644 libcxx/include/__cxx03/__algorithm/is_partitioned.h
create mode 100644 libcxx/include/__cxx03/__algorithm/is_permutation.h
create mode 100644 libcxx/include/__cxx03/__algorithm/is_sorted.h
create mode 100644 libcxx/include/__cxx03/__algorithm/is_sorted_until.h
create mode 100644 libcxx/include/__cxx03/__algorithm/iter_swap.h
create mode 100644 libcxx/include/__cxx03/__algorithm/iterator_operations.h
create mode 100644 libcxx/include/__cxx03/__algorithm/lexicographical_compare.h
create mode 100644 libcxx/include/__cxx03/__algorithm/lexicographical_compare_three_way.h
create mode 100644 libcxx/include/__cxx03/__algorithm/lower_bound.h
create mode 100644 libcxx/include/__cxx03/__algorithm/make_heap.h
create mode 100644 libcxx/include/__cxx03/__algorithm/make_projected.h
create mode 100644 libcxx/include/__cxx03/__algorithm/max.h
create mode 100644 libcxx/include/__cxx03/__algorithm/max_element.h
create mode 100644 libcxx/include/__cxx03/__algorithm/merge.h
create mode 100644 libcxx/include/__cxx03/__algorithm/min.h
create mode 100644 libcxx/include/__cxx03/__algorithm/min_element.h
create mode 100644 libcxx/include/__cxx03/__algorithm/min_max_result.h
create mode 100644 libcxx/include/__cxx03/__algorithm/minmax.h
create mode 100644 libcxx/include/__cxx03/__algorithm/minmax_element.h
create mode 100644 libcxx/include/__cxx03/__algorithm/mismatch.h
create mode 100644 libcxx/include/__cxx03/__algorithm/move.h
create mode 100644 libcxx/include/__cxx03/__algorithm/move_backward.h
create mode 100644 libcxx/include/__cxx03/__algorithm/next_permutation.h
create mode 100644 libcxx/include/__cxx03/__algorithm/none_of.h
create mode 100644 libcxx/include/__cxx03/__algorithm/nth_element.h
create mode 100644 libcxx/include/__cxx03/__algorithm/partial_sort.h
create mode 100644 libcxx/include/__cxx03/__algorithm/partial_sort_copy.h
create mode 100644 libcxx/include/__cxx03/__algorithm/partition.h
create mode 100644 libcxx/include/__cxx03/__algorithm/partition_copy.h
create mode 100644 libcxx/include/__cxx03/__algorithm/partition_point.h
create mode 100644 libcxx/include/__cxx03/__algorithm/pop_heap.h
create mode 100644 libcxx/include/__cxx03/__algorithm/prev_permutation.h
create mode 100644 libcxx/include/__cxx03/__algorithm/pstl.h
create mode 100644 libcxx/include/__cxx03/__algorithm/push_heap.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_adjacent_find.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_all_of.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_any_of.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_binary_search.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_clamp.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_contains.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_contains_subrange.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_copy.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_copy_backward.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_copy_if.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_copy_n.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_count.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_count_if.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_ends_with.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_equal.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_equal_range.h
create mode 100644 libcxx/include/__cxx03/__algorithm/ranges_fill.h
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diff --git a/libcxx/include/__cxx03/CMakeLists.txt b/libcxx/include/__cxx03/CMakeLists.txt
new file mode 100644
index 00000000000000..32579272858a8e
--- /dev/null
+++ b/libcxx/include/__cxx03/CMakeLists.txt
@@ -0,0 +1,1092 @@
+set(files
+ __algorithm/adjacent_find.h
+ __algorithm/all_of.h
+ __algorithm/any_of.h
+ __algorithm/binary_search.h
+ __algorithm/clamp.h
+ __algorithm/comp.h
+ __algorithm/comp_ref_type.h
+ __algorithm/copy.h
+ __algorithm/copy_backward.h
+ __algorithm/copy_if.h
+ __algorithm/copy_move_common.h
+ __algorithm/copy_n.h
+ __algorithm/count.h
+ __algorithm/count_if.h
+ __algorithm/equal.h
+ __algorithm/equal_range.h
+ __algorithm/fill.h
+ __algorithm/fill_n.h
+ __algorithm/find.h
+ __algorithm/find_end.h
+ __algorithm/find_first_of.h
+ __algorithm/find_if.h
+ __algorithm/find_if_not.h
+ __algorithm/find_segment_if.h
+ __algorithm/fold.h
+ __algorithm/for_each.h
+ __algorithm/for_each_n.h
+ __algorithm/for_each_segment.h
+ __algorithm/generate.h
+ __algorithm/generate_n.h
+ __algorithm/half_positive.h
+ __algorithm/in_found_result.h
+ __algorithm/in_fun_result.h
+ __algorithm/in_in_out_result.h
+ __algorithm/in_in_result.h
+ __algorithm/in_out_out_result.h
+ __algorithm/in_out_result.h
+ __algorithm/includes.h
+ __algorithm/inplace_merge.h
+ __algorithm/is_heap.h
+ __algorithm/is_heap_until.h
+ __algorithm/is_partitioned.h
+ __algorithm/is_permutation.h
+ __algorithm/is_sorted.h
+ __algorithm/is_sorted_until.h
+ __algorithm/iter_swap.h
+ __algorithm/iterator_operations.h
+ __algorithm/lexicographical_compare.h
+ __algorithm/lexicographical_compare_three_way.h
+ __algorithm/lower_bound.h
+ __algorithm/make_heap.h
+ __algorithm/make_projected.h
+ __algorithm/max.h
+ __algorithm/max_element.h
+ __algorithm/merge.h
+ __algorithm/min.h
+ __algorithm/min_element.h
+ __algorithm/min_max_result.h
+ __algorithm/minmax.h
+ __algorithm/minmax_element.h
+ __algorithm/mismatch.h
+ __algorithm/move.h
+ __algorithm/move_backward.h
+ __algorithm/next_permutation.h
+ __algorithm/none_of.h
+ __algorithm/nth_element.h
+ __algorithm/partial_sort.h
+ __algorithm/partial_sort_copy.h
+ __algorithm/partition.h
+ __algorithm/partition_copy.h
+ __algorithm/partition_point.h
+ __algorithm/pop_heap.h
+ __algorithm/prev_permutation.h
+ __algorithm/pstl.h
+ __algorithm/push_heap.h
+ __algorithm/ranges_adjacent_find.h
+ __algorithm/ranges_all_of.h
+ __algorithm/ranges_any_of.h
+ __algorithm/ranges_binary_search.h
+ __algorithm/ranges_clamp.h
+ __algorithm/ranges_contains.h
+ __algorithm/ranges_contains_subrange.h
+ __algorithm/ranges_copy.h
+ __algorithm/ranges_copy_backward.h
+ __algorithm/ranges_copy_if.h
+ __algorithm/ranges_copy_n.h
+ __algorithm/ranges_count.h
+ __algorithm/ranges_count_if.h
+ __algorithm/ranges_ends_with.h
+ __algorithm/ranges_equal.h
+ __algorithm/ranges_equal_range.h
+ __algorithm/ranges_fill.h
+ __algorithm/ranges_fill_n.h
+ __algorithm/ranges_find.h
+ __algorithm/ranges_find_end.h
+ __algorithm/ranges_find_first_of.h
+ __algorithm/ranges_find_if.h
+ __algorithm/ranges_find_if_not.h
+ __algorithm/ranges_find_last.h
+ __algorithm/ranges_for_each.h
+ __algorithm/ranges_for_each_n.h
+ __algorithm/ranges_generate.h
+ __algorithm/ranges_generate_n.h
+ __algorithm/ranges_includes.h
+ __algorithm/ranges_inplace_merge.h
+ __algorithm/ranges_is_heap.h
+ __algorithm/ranges_is_heap_until.h
+ __algorithm/ranges_is_partitioned.h
+ __algorithm/ranges_is_permutation.h
+ __algorithm/ranges_is_sorted.h
+ __algorithm/ranges_is_sorted_until.h
+ __algorithm/ranges_iterator_concept.h
+ __algorithm/ranges_lexicographical_compare.h
+ __algorithm/ranges_lower_bound.h
+ __algorithm/ranges_make_heap.h
+ __algorithm/ranges_max.h
+ __algorithm/ranges_max_element.h
+ __algorithm/ranges_merge.h
+ __algorithm/ranges_min.h
+ __algorithm/ranges_min_element.h
+ __algorithm/ranges_minmax.h
+ __algorithm/ranges_minmax_element.h
+ __algorithm/ranges_mismatch.h
+ __algorithm/ranges_move.h
+ __algorithm/ranges_move_backward.h
+ __algorithm/ranges_next_permutation.h
+ __algorithm/ranges_none_of.h
+ __algorithm/ranges_nth_element.h
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+ __type_traits/is_object.h
+ __type_traits/is_pod.h
+ __type_traits/is_pointer.h
+ __type_traits/is_polymorphic.h
+ __type_traits/is_primary_template.h
+ __type_traits/is_reference.h
+ __type_traits/is_reference_wrapper.h
+ __type_traits/is_referenceable.h
+ __type_traits/is_same.h
+ __type_traits/is_scalar.h
+ __type_traits/is_signed.h
+ __type_traits/is_signed_integer.h
+ __type_traits/is_specialization.h
+ __type_traits/is_standard_layout.h
+ __type_traits/is_swappable.h
+ __type_traits/is_trivial.h
+ __type_traits/is_trivially_assignable.h
+ __type_traits/is_trivially_constructible.h
+ __type_traits/is_trivially_copyable.h
+ __type_traits/is_trivially_destructible.h
+ __type_traits/is_trivially_lexicographically_comparable.h
+ __type_traits/is_trivially_relocatable.h
+ __type_traits/is_unbounded_array.h
+ __type_traits/is_union.h
+ __type_traits/is_unsigned.h
+ __type_traits/is_unsigned_integer.h
+ __type_traits/is_valid_expansion.h
+ __type_traits/is_void.h
+ __type_traits/is_volatile.h
+ __type_traits/lazy.h
+ __type_traits/make_32_64_or_128_bit.h
+ __type_traits/make_const_lvalue_ref.h
+ __type_traits/make_signed.h
+ __type_traits/make_unsigned.h
+ __type_traits/maybe_const.h
+ __type_traits/nat.h
+ __type_traits/negation.h
+ __type_traits/noexcept_move_assign_container.h
+ __type_traits/promote.h
+ __type_traits/rank.h
+ __type_traits/remove_all_extents.h
+ __type_traits/remove_const.h
+ __type_traits/remove_const_ref.h
+ __type_traits/remove_cv.h
+ __type_traits/remove_cvref.h
+ __type_traits/remove_extent.h
+ __type_traits/remove_pointer.h
+ __type_traits/remove_reference.h
+ __type_traits/remove_volatile.h
+ __type_traits/result_of.h
+ __type_traits/strip_signature.h
+ __type_traits/type_identity.h
+ __type_traits/type_list.h
+ __type_traits/underlying_type.h
+ __type_traits/unwrap_ref.h
+ __type_traits/void_t.h
+ __undef_macros
+ __utility/as_const.h
+ __utility/as_lvalue.h
+ __utility/auto_cast.h
+ __utility/cmp.h
+ __utility/convert_to_integral.h
+ __utility/declval.h
+ __utility/empty.h
+ __utility/exception_guard.h
+ __utility/exchange.h
+ __utility/forward.h
+ __utility/forward_like.h
+ __utility/in_place.h
+ __utility/integer_sequence.h
+ __utility/is_pointer_in_range.h
+ __utility/is_valid_range.h
+ __utility/move.h
+ __utility/no_destroy.h
+ __utility/pair.h
+ __utility/piecewise_construct.h
+ __utility/priority_tag.h
+ __utility/private_constructor_tag.h
+ __utility/rel_ops.h
+ __utility/small_buffer.h
+ __utility/swap.h
+ __utility/to_underlying.h
+ __utility/unreachable.h
+ __variant/monostate.h
+ __verbose_abort
+ algorithm
+ any
+ array
+ atomic
+ barrier
+ bit
+ bitset
+ cassert
+ ccomplex
+ cctype
+ cerrno
+ cfenv
+ cfloat
+ charconv
+ chrono
+ cinttypes
+ ciso646
+ climits
+ clocale
+ cmath
+ codecvt
+ compare
+ complex
+ complex.h
+ concepts
+ condition_variable
+ coroutine
+ csetjmp
+ csignal
+ cstdarg
+ cstdbool
+ cstddef
+ cstdint
+ cstdio
+ cstdlib
+ cstring
+ ctgmath
+ ctime
+ ctype.h
+ cuchar
+ cwchar
+ cwctype
+ deque
+ errno.h
+ exception
+ execution
+ expected
+ experimental/__config
+ experimental/__simd/aligned_tag.h
+ experimental/__simd/declaration.h
+ experimental/__simd/reference.h
+ experimental/__simd/scalar.h
+ experimental/__simd/simd.h
+ experimental/__simd/simd_mask.h
+ experimental/__simd/traits.h
+ experimental/__simd/utility.h
+ experimental/__simd/vec_ext.h
+ experimental/iterator
+ experimental/memory
+ experimental/propagate_const
+ experimental/simd
+ experimental/type_traits
+ experimental/utility
+ ext/__hash
+ ext/hash_map
+ ext/hash_set
+ fenv.h
+ filesystem
+ float.h
+ format
+ forward_list
+ fstream
+ functional
+ future
+ initializer_list
+ inttypes.h
+ iomanip
+ ios
+ iosfwd
+ iostream
+ istream
+ iterator
+ latch
+ limits
+ list
+ locale
+ locale.h
+ map
+ math.h
+ mdspan
+ memory
+ memory_resource
+ module.modulemap
+ mutex
+ new
+ numbers
+ numeric
+ optional
+ ostream
+ print
+ queue
+ random
+ ranges
+ ratio
+ regex
+ scoped_allocator
+ semaphore
+ set
+ shared_mutex
+ source_location
+ span
+ sstream
+ stack
+ stdatomic.h
+ stdbool.h
+ stddef.h
+ stdexcept
+ stdint.h
+ stdio.h
+ stdlib.h
+ stop_token
+ streambuf
+ string
+ string.h
+ string_view
+ strstream
+ syncstream
+ system_error
+ tgmath.h
+ thread
+ tuple
+ type_traits
+ typeindex
+ typeinfo
+ uchar.h
+ unordered_map
+ unordered_set
+ utility
+ valarray
+ variant
+ vector
+ version
+ wchar.h
+ wctype.h
+ )
+
+configure_file("__config_site.in" "${LIBCXX_GENERATED_INCLUDE_TARGET_DIR}/__config_site" @ONLY)
+configure_file("${LIBCXX_ASSERTION_HANDLER_FILE}" "${LIBCXX_GENERATED_INCLUDE_DIR}/__assertion_handler" COPYONLY)
+
+set(_all_includes "${LIBCXX_GENERATED_INCLUDE_TARGET_DIR}/__config_site"
+ "${LIBCXX_GENERATED_INCLUDE_DIR}/__assertion_handler")
+foreach(f ${files})
+ set(src "${CMAKE_CURRENT_SOURCE_DIR}/${f}")
+ set(dst "${LIBCXX_GENERATED_INCLUDE_DIR}/${f}")
+ add_custom_command(OUTPUT ${dst}
+ DEPENDS ${src}
+ COMMAND ${CMAKE_COMMAND} -E copy_if_different ${src} ${dst}
+ COMMENT "Copying CXX header ${f}")
+ list(APPEND _all_includes "${dst}")
+endforeach()
+
+# Generate the IWYU mapping. This depends on all header files but it's also considered as an
+# "include" for dependency tracking.
+add_custom_command(OUTPUT "${LIBCXX_GENERATED_INCLUDE_DIR}/libcxx.imp"
+ COMMAND "${Python3_EXECUTABLE}" "${LIBCXX_SOURCE_DIR}/utils/generate_iwyu_mapping.py" "-o" "${LIBCXX_GENERATED_INCLUDE_DIR}/libcxx.imp"
+ DEPENDS ${_all_includes}
+ COMMENT "Generate the mapping file for include-what-you-use"
+)
+list(APPEND _all_includes "${LIBCXX_GENERATED_INCLUDE_DIR}/libcxx.imp")
+
+add_custom_target(generate-cxx-headers ALL DEPENDS ${_all_includes})
+
+add_library(cxx-headers INTERFACE)
+target_link_libraries(cxx-headers INTERFACE libcxx-libc-headers libcxx-abi-headers)
+add_dependencies(cxx-headers generate-cxx-headers)
+# It's important that the arch directory be included first so that its header files
+# which interpose on the default include dir be included instead of the default ones.
+target_include_directories(cxx-headers INTERFACE ${LIBCXX_GENERATED_INCLUDE_TARGET_DIR}
+ ${LIBCXX_GENERATED_INCLUDE_DIR})
+
+if (LIBCXX_INSTALL_HEADERS)
+ foreach(file ${files})
+ get_filename_component(dir ${file} DIRECTORY)
+ install(FILES ${file}
+ DESTINATION "${LIBCXX_INSTALL_INCLUDE_DIR}/${dir}"
+ COMPONENT cxx-headers
+ PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
+ )
+ endforeach()
+
+ # Install the generated __config_site file to the per-target include dir.
+ install(FILES "${LIBCXX_GENERATED_INCLUDE_TARGET_DIR}/__config_site"
+ DESTINATION "${LIBCXX_INSTALL_INCLUDE_TARGET_DIR}"
+ PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
+ COMPONENT cxx-headers)
+
+ # Install the generated __assertion_handler file to the generic include dir.
+ install(FILES "${LIBCXX_GENERATED_INCLUDE_DIR}/__assertion_handler"
+ DESTINATION "${LIBCXX_INSTALL_INCLUDE_DIR}"
+ PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
+ COMPONENT cxx-headers)
+
+ # Install the generated IWYU file to the generic include dir.
+ install(FILES "${LIBCXX_GENERATED_INCLUDE_DIR}/libcxx.imp"
+ DESTINATION "${LIBCXX_INSTALL_INCLUDE_DIR}"
+ PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
+ COMPONENT cxx-headers)
+
+ if (NOT CMAKE_CONFIGURATION_TYPES)
+ add_custom_target(install-cxx-headers
+ DEPENDS cxx-headers
+ COMMAND "${CMAKE_COMMAND}"
+ -DCMAKE_INSTALL_COMPONENT=cxx-headers
+ -P "${CMAKE_BINARY_DIR}/cmake_install.cmake")
+ # Stripping is a no-op for headers
+ add_custom_target(install-cxx-headers-stripped DEPENDS install-cxx-headers)
+ endif()
+endif()
diff --git a/libcxx/include/__cxx03/__algorithm/adjacent_find.h b/libcxx/include/__cxx03/__algorithm/adjacent_find.h
new file mode 100644
index 00000000000000..6f15456e3a4d07
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/adjacent_find.h
@@ -0,0 +1,58 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_ADJACENT_FIND_H
+#define _LIBCPP___ALGORITHM_ADJACENT_FIND_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Iter, class _Sent, class _BinaryPredicate>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter
+__adjacent_find(_Iter __first, _Sent __last, _BinaryPredicate&& __pred) {
+ if (__first == __last)
+ return __first;
+ _Iter __i = __first;
+ while (++__i != __last) {
+ if (__pred(*__first, *__i))
+ return __first;
+ __first = __i;
+ }
+ return __i;
+}
+
+template <class _ForwardIterator, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+adjacent_find(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred) {
+ return std::__adjacent_find(std::move(__first), std::move(__last), __pred);
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+adjacent_find(_ForwardIterator __first, _ForwardIterator __last) {
+ return std::adjacent_find(std::move(__first), std::move(__last), __equal_to());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_ADJACENT_FIND_H
diff --git a/libcxx/include/__cxx03/__algorithm/all_of.h b/libcxx/include/__cxx03/__algorithm/all_of.h
new file mode 100644
index 00000000000000..ec84eea7592966
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/all_of.h
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_ALL_OF_H
+#define _LIBCPP___ALGORITHM_ALL_OF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+all_of(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
+ for (; __first != __last; ++__first)
+ if (!__pred(*__first))
+ return false;
+ return true;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_ALL_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/any_of.h b/libcxx/include/__cxx03/__algorithm/any_of.h
new file mode 100644
index 00000000000000..b5ff778c4171dc
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/any_of.h
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_ANY_OF_H
+#define _LIBCPP___ALGORITHM_ANY_OF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+any_of(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ return true;
+ return false;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_ANY_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/binary_search.h b/libcxx/include/__cxx03/__algorithm/binary_search.h
new file mode 100644
index 00000000000000..6065fc37274dce
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/binary_search.h
@@ -0,0 +1,39 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_BINARY_SEARCH_H
+#define _LIBCPP___ALGORITHM_BINARY_SEARCH_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/lower_bound.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, _Compare __comp) {
+ __first = std::lower_bound<_ForwardIterator, _Tp, __comp_ref_type<_Compare> >(__first, __last, __value, __comp);
+ return __first != __last && !__comp(__value, *__first);
+}
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ return std::binary_search(__first, __last, __value, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_BINARY_SEARCH_H
diff --git a/libcxx/include/__cxx03/__algorithm/clamp.h b/libcxx/include/__cxx03/__algorithm/clamp.h
new file mode 100644
index 00000000000000..1a5a3d0744be9c
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/clamp.h
@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_CLAMP_H
+#define _LIBCPP___ALGORITHM_CLAMP_H
+
+#include <__algorithm/comp.h>
+#include <__assert>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class _Compare>
+[[nodiscard]] inline _LIBCPP_HIDE_FROM_ABI constexpr const _Tp&
+clamp(_LIBCPP_LIFETIMEBOUND const _Tp& __v,
+ _LIBCPP_LIFETIMEBOUND const _Tp& __lo,
+ _LIBCPP_LIFETIMEBOUND const _Tp& __hi,
+ _Compare __comp) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
+ return __comp(__v, __lo) ? __lo : __comp(__hi, __v) ? __hi : __v;
+}
+
+template <class _Tp>
+[[nodiscard]] inline _LIBCPP_HIDE_FROM_ABI constexpr const _Tp&
+clamp(_LIBCPP_LIFETIMEBOUND const _Tp& __v,
+ _LIBCPP_LIFETIMEBOUND const _Tp& __lo,
+ _LIBCPP_LIFETIMEBOUND const _Tp& __hi) {
+ return std::clamp(__v, __lo, __hi, __less<>());
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_CLAMP_H
diff --git a/libcxx/include/__cxx03/__algorithm/comp.h b/libcxx/include/__cxx03/__algorithm/comp.h
new file mode 100644
index 00000000000000..a0fa88d6d2acd3
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/comp.h
@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COMP_H
+#define _LIBCPP___ALGORITHM_COMP_H
+
+#include <__config>
+#include <__type_traits/desugars_to.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __equal_to {
+ template <class _T1, class _T2>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _T1& __x, const _T2& __y) const {
+ return __x == __y;
+ }
+};
+
+template <class _Tp, class _Up>
+inline const bool __desugars_to_v<__equal_tag, __equal_to, _Tp, _Up> = true;
+
+// The definition is required because __less is part of the ABI, but it's empty
+// because all comparisons should be transparent.
+template <class _T1 = void, class _T2 = _T1>
+struct __less {};
+
+template <>
+struct __less<void, void> {
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _Tp& __lhs, const _Up& __rhs) const {
+ return __lhs < __rhs;
+ }
+};
+
+template <class _Tp>
+inline const bool __desugars_to_v<__less_tag, __less<>, _Tp, _Tp> = true;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_COMP_H
diff --git a/libcxx/include/__cxx03/__algorithm/comp_ref_type.h b/libcxx/include/__cxx03/__algorithm/comp_ref_type.h
new file mode 100644
index 00000000000000..c367fbb91ac282
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/comp_ref_type.h
@@ -0,0 +1,67 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COMP_REF_TYPE_H
+#define _LIBCPP___ALGORITHM_COMP_REF_TYPE_H
+
+#include <__assert>
+#include <__config>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Compare>
+struct __debug_less {
+ _Compare& __comp_;
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI __debug_less(_Compare& __c) : __comp_(__c) {}
+
+ template <class _Tp, class _Up>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Up& __y) {
+ bool __r = __comp_(__x, __y);
+ if (__r)
+ __do_compare_assert(0, __y, __x);
+ return __r;
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(_Tp& __x, _Up& __y) {
+ bool __r = __comp_(__x, __y);
+ if (__r)
+ __do_compare_assert(0, __y, __x);
+ return __r;
+ }
+
+ template <class _LHS, class _RHS>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 inline
+ _LIBCPP_HIDE_FROM_ABI decltype((void)std::declval<_Compare&>()(std::declval<_LHS&>(), std::declval<_RHS&>()))
+ __do_compare_assert(int, _LHS& __l, _RHS& __r) {
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(!__comp_(__l, __r), "Comparator does not induce a strict weak ordering");
+ (void)__l;
+ (void)__r;
+ }
+
+ template <class _LHS, class _RHS>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 inline _LIBCPP_HIDE_FROM_ABI void __do_compare_assert(long, _LHS&, _RHS&) {}
+};
+
+// Pass the comparator by lvalue reference. Or in the debug mode, using a debugging wrapper that stores a reference.
+#if _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_DEBUG
+template <class _Comp>
+using __comp_ref_type = __debug_less<_Comp>;
+#else
+template <class _Comp>
+using __comp_ref_type = _Comp&;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_COMP_REF_TYPE_H
diff --git a/libcxx/include/__cxx03/__algorithm/copy.h b/libcxx/include/__cxx03/__algorithm/copy.h
new file mode 100644
index 00000000000000..0890b895f54092
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/copy.h
@@ -0,0 +1,123 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COPY_H
+#define _LIBCPP___ALGORITHM_COPY_H
+
+#include <__algorithm/copy_move_common.h>
+#include <__algorithm/for_each_segment.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min.h>
+#include <__config>
+#include <__iterator/segmented_iterator.h>
+#include <__type_traits/common_type.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class, class _InIter, class _Sent, class _OutIter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> __copy(_InIter, _Sent, _OutIter);
+
+template <class _AlgPolicy>
+struct __copy_impl {
+ template <class _InIter, class _Sent, class _OutIter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+ while (__first != __last) {
+ *__result = *__first;
+ ++__first;
+ ++__result;
+ }
+
+ return std::make_pair(std::move(__first), std::move(__result));
+ }
+
+ template <class _InIter, class _OutIter>
+ struct _CopySegment {
+ using _Traits = __segmented_iterator_traits<_InIter>;
+
+ _OutIter& __result_;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit _CopySegment(_OutIter& __result)
+ : __result_(__result) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+ operator()(typename _Traits::__local_iterator __lfirst, typename _Traits::__local_iterator __llast) {
+ __result_ = std::__copy<_AlgPolicy>(__lfirst, __llast, std::move(__result_)).second;
+ }
+ };
+
+ template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+ std::__for_each_segment(__first, __last, _CopySegment<_InIter, _OutIter>(__result));
+ return std::make_pair(__last, std::move(__result));
+ }
+
+ template <class _InIter,
+ class _OutIter,
+ __enable_if_t<__has_random_access_iterator_category<_InIter>::value &&
+ !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+ using _Traits = __segmented_iterator_traits<_OutIter>;
+ using _DiffT = typename common_type<__iter_diff_t<_InIter>, __iter_diff_t<_OutIter> >::type;
+
+ if (__first == __last)
+ return std::make_pair(std::move(__first), std::move(__result));
+
+ auto __local_first = _Traits::__local(__result);
+ auto __segment_iterator = _Traits::__segment(__result);
+ while (true) {
+ auto __local_last = _Traits::__end(__segment_iterator);
+ auto __size = std::min<_DiffT>(__local_last - __local_first, __last - __first);
+ auto __iters = std::__copy<_AlgPolicy>(__first, __first + __size, __local_first);
+ __first = std::move(__iters.first);
+
+ if (__first == __last)
+ return std::make_pair(std::move(__first), _Traits::__compose(__segment_iterator, std::move(__iters.second)));
+
+ __local_first = _Traits::__begin(++__segment_iterator);
+ }
+ }
+
+ // At this point, the iterators have been unwrapped so any `contiguous_iterator` has been unwrapped to a pointer.
+ template <class _In, class _Out, __enable_if_t<__can_lower_copy_assignment_to_memmove<_In, _Out>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
+ operator()(_In* __first, _In* __last, _Out* __result) const {
+ return std::__copy_trivial_impl(__first, __last, __result);
+ }
+};
+
+template <class _AlgPolicy, class _InIter, class _Sent, class _OutIter>
+pair<_InIter, _OutIter> inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
+__copy(_InIter __first, _Sent __last, _OutIter __result) {
+ return std::__copy_move_unwrap_iters<__copy_impl<_AlgPolicy> >(
+ std::move(__first), std::move(__last), std::move(__result));
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
+ return std::__copy<_ClassicAlgPolicy>(__first, __last, __result).second;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/copy_backward.h b/libcxx/include/__cxx03/__algorithm/copy_backward.h
new file mode 100644
index 00000000000000..73dc846a975a44
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/copy_backward.h
@@ -0,0 +1,137 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COPY_BACKWARD_H
+#define _LIBCPP___ALGORITHM_COPY_BACKWARD_H
+
+#include <__algorithm/copy_move_common.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min.h>
+#include <__config>
+#include <__iterator/segmented_iterator.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _InIter, class _Sent, class _OutIter>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_InIter, _OutIter>
+__copy_backward(_InIter __first, _Sent __last, _OutIter __result);
+
+template <class _AlgPolicy>
+struct __copy_backward_impl {
+ template <class _InIter, class _Sent, class _OutIter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+ auto __last_iter = _IterOps<_AlgPolicy>::next(__first, __last);
+ auto __original_last_iter = __last_iter;
+
+ while (__first != __last_iter) {
+ *--__result = *--__last_iter;
+ }
+
+ return std::make_pair(std::move(__original_last_iter), std::move(__result));
+ }
+
+ template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+ using _Traits = __segmented_iterator_traits<_InIter>;
+ auto __sfirst = _Traits::__segment(__first);
+ auto __slast = _Traits::__segment(__last);
+ if (__sfirst == __slast) {
+ auto __iters =
+ std::__copy_backward<_AlgPolicy>(_Traits::__local(__first), _Traits::__local(__last), std::move(__result));
+ return std::make_pair(__last, __iters.second);
+ }
+
+ __result =
+ std::__copy_backward<_AlgPolicy>(_Traits::__begin(__slast), _Traits::__local(__last), std::move(__result))
+ .second;
+ --__slast;
+ while (__sfirst != __slast) {
+ __result =
+ std::__copy_backward<_AlgPolicy>(_Traits::__begin(__slast), _Traits::__end(__slast), std::move(__result))
+ .second;
+ --__slast;
+ }
+ __result = std::__copy_backward<_AlgPolicy>(_Traits::__local(__first), _Traits::__end(__slast), std::move(__result))
+ .second;
+ return std::make_pair(__last, std::move(__result));
+ }
+
+ template <class _InIter,
+ class _OutIter,
+ __enable_if_t<__has_random_access_iterator_category<_InIter>::value &&
+ !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+ using _Traits = __segmented_iterator_traits<_OutIter>;
+ auto __orig_last = __last;
+ auto __segment_iterator = _Traits::__segment(__result);
+
+ // When the range contains no elements, __result might not be a valid iterator
+ if (__first == __last)
+ return std::make_pair(__first, __result);
+
+ auto __local_last = _Traits::__local(__result);
+ while (true) {
+ using _DiffT = typename common_type<__iter_diff_t<_InIter>, __iter_diff_t<_OutIter> >::type;
+
+ auto __local_first = _Traits::__begin(__segment_iterator);
+ auto __size = std::min<_DiffT>(__local_last - __local_first, __last - __first);
+ auto __iter = std::__copy_backward<_AlgPolicy>(__last - __size, __last, __local_last).second;
+ __last -= __size;
+
+ if (__first == __last)
+ return std::make_pair(std::move(__orig_last), _Traits::__compose(__segment_iterator, std::move(__iter)));
+ --__segment_iterator;
+ __local_last = _Traits::__end(__segment_iterator);
+ }
+ }
+
+ // At this point, the iterators have been unwrapped so any `contiguous_iterator` has been unwrapped to a pointer.
+ template <class _In, class _Out, __enable_if_t<__can_lower_copy_assignment_to_memmove<_In, _Out>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
+ operator()(_In* __first, _In* __last, _Out* __result) const {
+ return std::__copy_backward_trivial_impl(__first, __last, __result);
+ }
+};
+
+template <class _AlgPolicy, class _BidirectionalIterator1, class _Sentinel, class _BidirectionalIterator2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_BidirectionalIterator1, _BidirectionalIterator2>
+__copy_backward(_BidirectionalIterator1 __first, _Sentinel __last, _BidirectionalIterator2 __result) {
+ return std::__copy_move_unwrap_iters<__copy_backward_impl<_AlgPolicy> >(
+ std::move(__first), std::move(__last), std::move(__result));
+}
+
+template <class _BidirectionalIterator1, class _BidirectionalIterator2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _BidirectionalIterator2
+copy_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last, _BidirectionalIterator2 __result) {
+ static_assert(std::is_copy_constructible<_BidirectionalIterator1>::value &&
+ std::is_copy_constructible<_BidirectionalIterator1>::value,
+ "Iterators must be copy constructible.");
+
+ return std::__copy_backward<_ClassicAlgPolicy>(std::move(__first), std::move(__last), std::move(__result)).second;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_COPY_BACKWARD_H
diff --git a/libcxx/include/__cxx03/__algorithm/copy_if.h b/libcxx/include/__cxx03/__algorithm/copy_if.h
new file mode 100644
index 00000000000000..228e4d22323e3c
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/copy_if.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COPY_IF_H
+#define _LIBCPP___ALGORITHM_COPY_IF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Predicate __pred) {
+ for (; __first != __last; ++__first) {
+ if (__pred(*__first)) {
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_COPY_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/copy_move_common.h b/libcxx/include/__cxx03/__algorithm/copy_move_common.h
new file mode 100644
index 00000000000000..8a98451a8f9653
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/copy_move_common.h
@@ -0,0 +1,114 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COPY_MOVE_COMMON_H
+#define _LIBCPP___ALGORITHM_COPY_MOVE_COMMON_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__algorithm/unwrap_range.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__string/constexpr_c_functions.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_always_bitcastable.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_trivially_assignable.h>
+#include <__type_traits/is_volatile.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Type traits.
+
+template <class _From, class _To>
+struct __can_lower_copy_assignment_to_memmove {
+ static const bool value =
+ // If the types are always bitcastable, it's valid to do a bitwise copy between them.
+ __is_always_bitcastable<_From, _To>::value &&
+ // Reject conversions that wouldn't be performed by the regular built-in assignment (e.g. between arrays).
+ is_trivially_assignable<_To&, const _From&>::value &&
+ // `memmove` doesn't accept `volatile` pointers, make sure the optimization SFINAEs away in that case.
+ !is_volatile<_From>::value && !is_volatile<_To>::value;
+};
+
+template <class _From, class _To>
+struct __can_lower_move_assignment_to_memmove {
+ static const bool value =
+ __is_always_bitcastable<_From, _To>::value && is_trivially_assignable<_To&, _From&&>::value &&
+ !is_volatile<_From>::value && !is_volatile<_To>::value;
+};
+
+// `memmove` algorithms implementation.
+
+template <class _In, class _Out>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
+__copy_trivial_impl(_In* __first, _In* __last, _Out* __result) {
+ const size_t __n = static_cast<size_t>(__last - __first);
+
+ std::__constexpr_memmove(__result, __first, __element_count(__n));
+
+ return std::make_pair(__last, __result + __n);
+}
+
+template <class _In, class _Out>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
+__copy_backward_trivial_impl(_In* __first, _In* __last, _Out* __result) {
+ const size_t __n = static_cast<size_t>(__last - __first);
+ __result -= __n;
+
+ std::__constexpr_memmove(__result, __first, __element_count(__n));
+
+ return std::make_pair(__last, __result);
+}
+
+// Iterator unwrapping and dispatching to the correct overload.
+
+template <class _InIter, class _OutIter>
+struct __can_rewrap
+ : integral_constant<bool, is_copy_constructible<_InIter>::value && is_copy_constructible<_OutIter>::value> {};
+
+template <class _Algorithm,
+ class _InIter,
+ class _Sent,
+ class _OutIter,
+ __enable_if_t<__can_rewrap<_InIter, _OutIter>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 pair<_InIter, _OutIter>
+__copy_move_unwrap_iters(_InIter __first, _Sent __last, _OutIter __out_first) {
+ auto __range = std::__unwrap_range(__first, std::move(__last));
+ auto __result = _Algorithm()(std::move(__range.first), std::move(__range.second), std::__unwrap_iter(__out_first));
+ return std::make_pair(std::__rewrap_range<_Sent>(std::move(__first), std::move(__result.first)),
+ std::__rewrap_iter(std::move(__out_first), std::move(__result.second)));
+}
+
+template <class _Algorithm,
+ class _InIter,
+ class _Sent,
+ class _OutIter,
+ __enable_if_t<!__can_rewrap<_InIter, _OutIter>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 pair<_InIter, _OutIter>
+__copy_move_unwrap_iters(_InIter __first, _Sent __last, _OutIter __out_first) {
+ return _Algorithm()(std::move(__first), std::move(__last), std::move(__out_first));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_COPY_MOVE_COMMON_H
diff --git a/libcxx/include/__cxx03/__algorithm/copy_n.h b/libcxx/include/__cxx03/__algorithm/copy_n.h
new file mode 100644
index 00000000000000..f93f39203a7e3b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/copy_n.h
@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COPY_N_H
+#define _LIBCPP___ALGORITHM_COPY_N_H
+
+#include <__algorithm/copy.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__utility/convert_to_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator,
+ class _Size,
+ class _OutputIterator,
+ __enable_if_t<__has_input_iterator_category<_InputIterator>::value &&
+ !__has_random_access_iterator_category<_InputIterator>::value,
+ int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+copy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result) {
+ typedef decltype(std::__convert_to_integral(__orig_n)) _IntegralSize;
+ _IntegralSize __n = __orig_n;
+ if (__n > 0) {
+ *__result = *__first;
+ ++__result;
+ for (--__n; __n > 0; --__n) {
+ ++__first;
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return __result;
+}
+
+template <class _InputIterator,
+ class _Size,
+ class _OutputIterator,
+ __enable_if_t<__has_random_access_iterator_category<_InputIterator>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+copy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result) {
+ typedef typename iterator_traits<_InputIterator>::difference_type difference_type;
+ typedef decltype(std::__convert_to_integral(__orig_n)) _IntegralSize;
+ _IntegralSize __n = __orig_n;
+ return std::copy(__first, __first + difference_type(__n), __result);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_COPY_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/count.h b/libcxx/include/__cxx03/__algorithm/count.h
new file mode 100644
index 00000000000000..1cfe7f631ac1b7
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/count.h
@@ -0,0 +1,92 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COUNT_H
+#define _LIBCPP___ALGORITHM_COUNT_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min.h>
+#include <__bit/invert_if.h>
+#include <__bit/popcount.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__fwd/bit_reference.h>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// generic implementation
+template <class _AlgPolicy, class _Iter, class _Sent, class _Tp, class _Proj>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename _IterOps<_AlgPolicy>::template __difference_type<_Iter>
+__count(_Iter __first, _Sent __last, const _Tp& __value, _Proj& __proj) {
+ typename _IterOps<_AlgPolicy>::template __difference_type<_Iter> __r(0);
+ for (; __first != __last; ++__first)
+ if (std::__invoke(__proj, *__first) == __value)
+ ++__r;
+ return __r;
+}
+
+// __bit_iterator implementation
+template <bool _ToCount, class _Cp, bool _IsConst>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename __bit_iterator<_Cp, _IsConst>::difference_type
+__count_bool(__bit_iterator<_Cp, _IsConst> __first, typename _Cp::size_type __n) {
+ using _It = __bit_iterator<_Cp, _IsConst>;
+ using __storage_type = typename _It::__storage_type;
+ using difference_type = typename _It::difference_type;
+
+ const int __bits_per_word = _It::__bits_per_word;
+ difference_type __r = 0;
+ // do first partial word
+ if (__first.__ctz_ != 0) {
+ __storage_type __clz_f = static_cast<__storage_type>(__bits_per_word - __first.__ctz_);
+ __storage_type __dn = std::min(__clz_f, __n);
+ __storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
+ __r = std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_) & __m);
+ __n -= __dn;
+ ++__first.__seg_;
+ }
+ // do middle whole words
+ for (; __n >= __bits_per_word; ++__first.__seg_, __n -= __bits_per_word)
+ __r += std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_));
+ // do last partial word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __r += std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_) & __m);
+ }
+ return __r;
+}
+
+template <class, class _Cp, bool _IsConst, class _Tp, class _Proj, __enable_if_t<__is_identity<_Proj>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __iter_diff_t<__bit_iterator<_Cp, _IsConst> >
+__count(__bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, const _Tp& __value, _Proj&) {
+ if (__value)
+ return std::__count_bool<true>(__first, static_cast<typename _Cp::size_type>(__last - __first));
+ return std::__count_bool<false>(__first, static_cast<typename _Cp::size_type>(__last - __first));
+}
+
+template <class _InputIterator, class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __iter_diff_t<_InputIterator>
+count(_InputIterator __first, _InputIterator __last, const _Tp& __value) {
+ __identity __proj;
+ return std::__count<_ClassicAlgPolicy>(__first, __last, __value, __proj);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_COUNT_H
diff --git a/libcxx/include/__cxx03/__algorithm/count_if.h b/libcxx/include/__cxx03/__algorithm/count_if.h
new file mode 100644
index 00000000000000..25782069d03275
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/count_if.h
@@ -0,0 +1,35 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_COUNT_IF_H
+#define _LIBCPP___ALGORITHM_COUNT_IF_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+typename iterator_traits<_InputIterator>::difference_type
+count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
+ typename iterator_traits<_InputIterator>::difference_type __r(0);
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ ++__r;
+ return __r;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_COUNT_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/equal.h b/libcxx/include/__cxx03/__algorithm/equal.h
new file mode 100644
index 00000000000000..bfc8f72f6eb195
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/equal.h
@@ -0,0 +1,133 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_EQUAL_H
+#define _LIBCPP___ALGORITHM_EQUAL_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__string/constexpr_c_functions.h>
+#include <__type_traits/desugars_to.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_equality_comparable.h>
+#include <__type_traits/is_volatile.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_iter_impl(
+ _InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate& __pred) {
+ for (; __first1 != __last1; ++__first1, (void)++__first2)
+ if (!__pred(*__first1, *__first2))
+ return false;
+ return true;
+}
+
+template <class _Tp,
+ class _Up,
+ class _BinaryPredicate,
+ __enable_if_t<__desugars_to_v<__equal_tag, _BinaryPredicate, _Tp, _Up> && !is_volatile<_Tp>::value &&
+ !is_volatile<_Up>::value && __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value,
+ int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+__equal_iter_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _BinaryPredicate&) {
+ return std::__constexpr_memcmp_equal(__first1, __first2, __element_count(__last1 - __first1));
+}
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred) {
+ return std::__equal_iter_impl(
+ std::__unwrap_iter(__first1), std::__unwrap_iter(__last1), std::__unwrap_iter(__first2), __pred);
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2) {
+ return std::equal(__first1, __last1, __first2, __equal_to());
+}
+
+#if _LIBCPP_STD_VER >= 14
+
+template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_impl(
+ _Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Sent2 __last2, _Pred& __comp, _Proj1& __proj1, _Proj2& __proj2) {
+ while (__first1 != __last1 && __first2 != __last2) {
+ if (!std::__invoke(__comp, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ return false;
+ ++__first1;
+ ++__first2;
+ }
+ return __first1 == __last1 && __first2 == __last2;
+}
+
+template <class _Tp,
+ class _Up,
+ class _Pred,
+ class _Proj1,
+ class _Proj2,
+ __enable_if_t<__desugars_to_v<__equal_tag, _Pred, _Tp, _Up> && __is_identity<_Proj1>::value &&
+ __is_identity<_Proj2>::value && !is_volatile<_Tp>::value && !is_volatile<_Up>::value &&
+ __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value,
+ int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+__equal_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _Up*, _Pred&, _Proj1&, _Proj2&) {
+ return std::__constexpr_memcmp_equal(__first1, __first2, __element_count(__last1 - __first1));
+}
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+equal(_InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _BinaryPredicate __pred) {
+ if constexpr (__has_random_access_iterator_category<_InputIterator1>::value &&
+ __has_random_access_iterator_category<_InputIterator2>::value) {
+ if (std::distance(__first1, __last1) != std::distance(__first2, __last2))
+ return false;
+ }
+ __identity __proj;
+ return std::__equal_impl(
+ std::__unwrap_iter(__first1),
+ std::__unwrap_iter(__last1),
+ std::__unwrap_iter(__first2),
+ std::__unwrap_iter(__last2),
+ __pred,
+ __proj,
+ __proj);
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2) {
+ return std::equal(__first1, __last1, __first2, __last2, __equal_to());
+}
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_EQUAL_H
diff --git a/libcxx/include/__cxx03/__algorithm/equal_range.h b/libcxx/include/__cxx03/__algorithm/equal_range.h
new file mode 100644
index 00000000000000..09bbf8f006021a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/equal_range.h
@@ -0,0 +1,85 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_EQUAL_RANGE_H
+#define _LIBCPP___ALGORITHM_EQUAL_RANGE_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/half_positive.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/lower_bound.h>
+#include <__algorithm/upper_bound.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/advance.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__type_traits/is_callable.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _Iter, class _Sent, class _Tp, class _Proj>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Iter, _Iter>
+__equal_range(_Iter __first, _Sent __last, const _Tp& __value, _Compare&& __comp, _Proj&& __proj) {
+ auto __len = _IterOps<_AlgPolicy>::distance(__first, __last);
+ _Iter __end = _IterOps<_AlgPolicy>::next(__first, __last);
+ while (__len != 0) {
+ auto __half_len = std::__half_positive(__len);
+ _Iter __mid = _IterOps<_AlgPolicy>::next(__first, __half_len);
+ if (std::__invoke(__comp, std::__invoke(__proj, *__mid), __value)) {
+ __first = ++__mid;
+ __len -= __half_len + 1;
+ } else if (std::__invoke(__comp, __value, std::__invoke(__proj, *__mid))) {
+ __end = __mid;
+ __len = __half_len;
+ } else {
+ _Iter __mp1 = __mid;
+ return pair<_Iter, _Iter>(std::__lower_bound<_AlgPolicy>(__first, __mid, __value, __comp, __proj),
+ std::__upper_bound<_AlgPolicy>(++__mp1, __end, __value, __comp, __proj));
+ }
+ }
+ return pair<_Iter, _Iter>(__first, __first);
+}
+
+template <class _ForwardIterator, class _Tp, class _Compare>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator, _ForwardIterator>
+equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, _Compare __comp) {
+ static_assert(__is_callable<_Compare, decltype(*__first), const _Tp&>::value, "The comparator has to be callable");
+ static_assert(is_copy_constructible<_ForwardIterator>::value, "Iterator has to be copy constructible");
+ return std::__equal_range<_ClassicAlgPolicy>(
+ std::move(__first),
+ std::move(__last),
+ __value,
+ static_cast<__comp_ref_type<_Compare> >(__comp),
+ std::__identity());
+}
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator, _ForwardIterator>
+equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ return std::equal_range(std::move(__first), std::move(__last), __value, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_EQUAL_RANGE_H
diff --git a/libcxx/include/__cxx03/__algorithm/fill.h b/libcxx/include/__cxx03/__algorithm/fill.h
new file mode 100644
index 00000000000000..1ce3eadb013d05
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/fill.h
@@ -0,0 +1,45 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FILL_H
+#define _LIBCPP___ALGORITHM_FILL_H
+
+#include <__algorithm/fill_n.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// fill isn't specialized for std::memset, because the compiler already optimizes the loop to a call to std::memset.
+
+template <class _ForwardIterator, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, forward_iterator_tag) {
+ for (; __first != __last; ++__first)
+ *__first = __value;
+}
+
+template <class _RandomAccessIterator, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__fill(_RandomAccessIterator __first, _RandomAccessIterator __last, const _Tp& __value, random_access_iterator_tag) {
+ std::fill_n(__first, __last - __first, __value);
+}
+
+template <class _ForwardIterator, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ std::__fill(__first, __last, __value, typename iterator_traits<_ForwardIterator>::iterator_category());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FILL_H
diff --git a/libcxx/include/__cxx03/__algorithm/fill_n.h b/libcxx/include/__cxx03/__algorithm/fill_n.h
new file mode 100644
index 00000000000000..f29633f88087f0
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/fill_n.h
@@ -0,0 +1,98 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FILL_N_H
+#define _LIBCPP___ALGORITHM_FILL_N_H
+
+#include <__algorithm/min.h>
+#include <__config>
+#include <__fwd/bit_reference.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__utility/convert_to_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// fill_n isn't specialized for std::memset, because the compiler already optimizes the loop to a call to std::memset.
+
+template <class _OutputIterator, class _Size, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+__fill_n(_OutputIterator __first, _Size __n, const _Tp& __value);
+
+template <bool _FillVal, class _Cp>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+__fill_n_bool(__bit_iterator<_Cp, false> __first, typename _Cp::size_type __n) {
+ using _It = __bit_iterator<_Cp, false>;
+ using __storage_type = typename _It::__storage_type;
+
+ const int __bits_per_word = _It::__bits_per_word;
+ // do first partial word
+ if (__first.__ctz_ != 0) {
+ __storage_type __clz_f = static_cast<__storage_type>(__bits_per_word - __first.__ctz_);
+ __storage_type __dn = std::min(__clz_f, __n);
+ __storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
+ if (_FillVal)
+ *__first.__seg_ |= __m;
+ else
+ *__first.__seg_ &= ~__m;
+ __n -= __dn;
+ ++__first.__seg_;
+ }
+ // do middle whole words
+ __storage_type __nw = __n / __bits_per_word;
+ std::__fill_n(std::__to_address(__first.__seg_), __nw, _FillVal ? static_cast<__storage_type>(-1) : 0);
+ __n -= __nw * __bits_per_word;
+ // do last partial word
+ if (__n > 0) {
+ __first.__seg_ += __nw;
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ if (_FillVal)
+ *__first.__seg_ |= __m;
+ else
+ *__first.__seg_ &= ~__m;
+ }
+}
+
+template <class _Cp, class _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cp, false>
+__fill_n(__bit_iterator<_Cp, false> __first, _Size __n, const bool& __value) {
+ if (__n > 0) {
+ if (__value)
+ std::__fill_n_bool<true>(__first, __n);
+ else
+ std::__fill_n_bool<false>(__first, __n);
+ }
+ return __first + __n;
+}
+
+template <class _OutputIterator, class _Size, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+__fill_n(_OutputIterator __first, _Size __n, const _Tp& __value) {
+ for (; __n > 0; ++__first, (void)--__n)
+ *__first = __value;
+ return __first;
+}
+
+template <class _OutputIterator, class _Size, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+fill_n(_OutputIterator __first, _Size __n, const _Tp& __value) {
+ return std::__fill_n(__first, std::__convert_to_integral(__n), __value);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_FILL_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/find.h b/libcxx/include/__cxx03/__algorithm/find.h
new file mode 100644
index 00000000000000..7f58dbb13a5776
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/find.h
@@ -0,0 +1,181 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FIND_H
+#define _LIBCPP___ALGORITHM_FIND_H
+
+#include <__algorithm/find_segment_if.h>
+#include <__algorithm/min.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__bit/countr.h>
+#include <__bit/invert_if.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__fwd/bit_reference.h>
+#include <__iterator/segmented_iterator.h>
+#include <__string/constexpr_c_functions.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_signed.h>
+#include <__utility/move.h>
+#include <limits>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+# include <cwchar>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// generic implementation
+template <class _Iter, class _Sent, class _Tp, class _Proj>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Iter
+__find(_Iter __first, _Sent __last, const _Tp& __value, _Proj& __proj) {
+ for (; __first != __last; ++__first)
+ if (std::__invoke(__proj, *__first) == __value)
+ break;
+ return __first;
+}
+
+// trivially equality comparable implementations
+template <class _Tp,
+ class _Up,
+ class _Proj,
+ __enable_if_t<__is_identity<_Proj>::value && __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value &&
+ sizeof(_Tp) == 1,
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp* __find(_Tp* __first, _Tp* __last, const _Up& __value, _Proj&) {
+ if (auto __ret = std::__constexpr_memchr(__first, __value, __last - __first))
+ return __ret;
+ return __last;
+}
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _Tp,
+ class _Up,
+ class _Proj,
+ __enable_if_t<__is_identity<_Proj>::value && __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value &&
+ sizeof(_Tp) == sizeof(wchar_t) && _LIBCPP_ALIGNOF(_Tp) >= _LIBCPP_ALIGNOF(wchar_t),
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp* __find(_Tp* __first, _Tp* __last, const _Up& __value, _Proj&) {
+ if (auto __ret = std::__constexpr_wmemchr(__first, __value, __last - __first))
+ return __ret;
+ return __last;
+}
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+// TODO: This should also be possible to get right with different signedness
+// cast integral types to allow vectorization
+template <class _Tp,
+ class _Up,
+ class _Proj,
+ __enable_if_t<__is_identity<_Proj>::value && !__libcpp_is_trivially_equality_comparable<_Tp, _Up>::value &&
+ is_integral<_Tp>::value && is_integral<_Up>::value &&
+ is_signed<_Tp>::value == is_signed<_Up>::value,
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp*
+__find(_Tp* __first, _Tp* __last, const _Up& __value, _Proj& __proj) {
+ if (__value < numeric_limits<_Tp>::min() || __value > numeric_limits<_Tp>::max())
+ return __last;
+ return std::__find(__first, __last, _Tp(__value), __proj);
+}
+
+// __bit_iterator implementation
+template <bool _ToFind, class _Cp, bool _IsConst>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, _IsConst>
+__find_bool(__bit_iterator<_Cp, _IsConst> __first, typename _Cp::size_type __n) {
+ using _It = __bit_iterator<_Cp, _IsConst>;
+ using __storage_type = typename _It::__storage_type;
+
+ const int __bits_per_word = _It::__bits_per_word;
+ // do first partial word
+ if (__first.__ctz_ != 0) {
+ __storage_type __clz_f = static_cast<__storage_type>(__bits_per_word - __first.__ctz_);
+ __storage_type __dn = std::min(__clz_f, __n);
+ __storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
+ __storage_type __b = std::__invert_if<!_ToFind>(*__first.__seg_) & __m;
+ if (__b)
+ return _It(__first.__seg_, static_cast<unsigned>(std::__libcpp_ctz(__b)));
+ if (__n == __dn)
+ return __first + __n;
+ __n -= __dn;
+ ++__first.__seg_;
+ }
+ // do middle whole words
+ for (; __n >= __bits_per_word; ++__first.__seg_, __n -= __bits_per_word) {
+ __storage_type __b = std::__invert_if<!_ToFind>(*__first.__seg_);
+ if (__b)
+ return _It(__first.__seg_, static_cast<unsigned>(std::__libcpp_ctz(__b)));
+ }
+ // do last partial word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __storage_type __b = std::__invert_if<!_ToFind>(*__first.__seg_) & __m;
+ if (__b)
+ return _It(__first.__seg_, static_cast<unsigned>(std::__libcpp_ctz(__b)));
+ }
+ return _It(__first.__seg_, static_cast<unsigned>(__n));
+}
+
+template <class _Cp, bool _IsConst, class _Tp, class _Proj, __enable_if_t<__is_identity<_Proj>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cp, _IsConst>
+__find(__bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, const _Tp& __value, _Proj&) {
+ if (static_cast<bool>(__value))
+ return std::__find_bool<true>(__first, static_cast<typename _Cp::size_type>(__last - __first));
+ return std::__find_bool<false>(__first, static_cast<typename _Cp::size_type>(__last - __first));
+}
+
+// segmented iterator implementation
+
+template <class>
+struct __find_segment;
+
+template <class _SegmentedIterator,
+ class _Tp,
+ class _Proj,
+ __enable_if_t<__is_segmented_iterator<_SegmentedIterator>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _SegmentedIterator
+__find(_SegmentedIterator __first, _SegmentedIterator __last, const _Tp& __value, _Proj& __proj) {
+ return std::__find_segment_if(std::move(__first), std::move(__last), __find_segment<_Tp>(__value), __proj);
+}
+
+template <class _Tp>
+struct __find_segment {
+ const _Tp& __value_;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __find_segment(const _Tp& __value) : __value_(__value) {}
+
+ template <class _InputIterator, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _InputIterator
+ operator()(_InputIterator __first, _InputIterator __last, _Proj& __proj) const {
+ return std::__find(__first, __last, __value_, __proj);
+ }
+};
+
+// public API
+template <class _InputIterator, class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _InputIterator
+find(_InputIterator __first, _InputIterator __last, const _Tp& __value) {
+ __identity __proj;
+ return std::__rewrap_iter(
+ __first, std::__find(std::__unwrap_iter(__first), std::__unwrap_iter(__last), __value, __proj));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_FIND_H
diff --git a/libcxx/include/__cxx03/__algorithm/find_end.h b/libcxx/include/__cxx03/__algorithm/find_end.h
new file mode 100644
index 00000000000000..7e08e7953534eb
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/find_end.h
@@ -0,0 +1,225 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FIND_END_OF_H
+#define _LIBCPP___ALGORITHM_FIND_END_OF_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/search.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/advance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/reverse_iterator.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template < class _AlgPolicy,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Pred,
+ class _Proj1,
+ class _Proj2>
+_LIBCPP_HIDE_FROM_ABI inline _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter1, _Iter1> __find_end_impl(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2,
+ forward_iterator_tag,
+ forward_iterator_tag) {
+ // modeled after search algorithm
+ _Iter1 __match_first = _IterOps<_AlgPolicy>::next(__first1, __last1); // __last1 is the "default" answer
+ _Iter1 __match_last = __match_first;
+ if (__first2 == __last2)
+ return pair<_Iter1, _Iter1>(__match_last, __match_last);
+ while (true) {
+ while (true) {
+ if (__first1 == __last1) // if source exhausted return last correct answer (or __last1 if never found)
+ return pair<_Iter1, _Iter1>(__match_first, __match_last);
+ if (std::__invoke(__pred, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ break;
+ ++__first1;
+ }
+ // *__first1 matches *__first2, now match elements after here
+ _Iter1 __m1 = __first1;
+ _Iter2 __m2 = __first2;
+ while (true) {
+ if (++__m2 == __last2) { // Pattern exhaused, record answer and search for another one
+ __match_first = __first1;
+ __match_last = ++__m1;
+ ++__first1;
+ break;
+ }
+ if (++__m1 == __last1) // Source exhausted, return last answer
+ return pair<_Iter1, _Iter1>(__match_first, __match_last);
+ // mismatch, restart with a new __first
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *__m1), std::__invoke(__proj2, *__m2))) {
+ ++__first1;
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template < class _IterOps,
+ class _Pred,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Proj1,
+ class _Proj2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter1 __find_end(
+ _Iter1 __first1,
+ _Sent1 __sent1,
+ _Iter2 __first2,
+ _Sent2 __sent2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2,
+ bidirectional_iterator_tag,
+ bidirectional_iterator_tag) {
+ auto __last1 = _IterOps::next(__first1, __sent1);
+ auto __last2 = _IterOps::next(__first2, __sent2);
+ // modeled after search algorithm (in reverse)
+ if (__first2 == __last2)
+ return __last1; // Everything matches an empty sequence
+ _Iter1 __l1 = __last1;
+ _Iter2 __l2 = __last2;
+ --__l2;
+ while (true) {
+ // Find last element in sequence 1 that matchs *(__last2-1), with a mininum of loop checks
+ while (true) {
+ if (__first1 == __l1) // return __last1 if no element matches *__first2
+ return __last1;
+ if (std::__invoke(__pred, std::__invoke(__proj1, *--__l1), std::__invoke(__proj2, *__l2)))
+ break;
+ }
+ // *__l1 matches *__l2, now match elements before here
+ _Iter1 __m1 = __l1;
+ _Iter2 __m2 = __l2;
+ while (true) {
+ if (__m2 == __first2) // If pattern exhausted, __m1 is the answer (works for 1 element pattern)
+ return __m1;
+ if (__m1 == __first1) // Otherwise if source exhaused, pattern not found
+ return __last1;
+
+ // if there is a mismatch, restart with a new __l1
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *--__m1), std::__invoke(__proj2, *--__m2))) {
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template < class _AlgPolicy,
+ class _Pred,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Proj1,
+ class _Proj2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Iter1 __find_end(
+ _Iter1 __first1,
+ _Sent1 __sent1,
+ _Iter2 __first2,
+ _Sent2 __sent2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2,
+ random_access_iterator_tag,
+ random_access_iterator_tag) {
+ typedef typename iterator_traits<_Iter1>::difference_type _D1;
+ auto __last1 = _IterOps<_AlgPolicy>::next(__first1, __sent1);
+ auto __last2 = _IterOps<_AlgPolicy>::next(__first2, __sent2);
+ // Take advantage of knowing source and pattern lengths. Stop short when source is smaller than pattern
+ auto __len2 = __last2 - __first2;
+ if (__len2 == 0)
+ return __last1;
+ auto __len1 = __last1 - __first1;
+ if (__len1 < __len2)
+ return __last1;
+ const _Iter1 __s = __first1 + _D1(__len2 - 1); // End of pattern match can't go before here
+ _Iter1 __l1 = __last1;
+ _Iter2 __l2 = __last2;
+ --__l2;
+ while (true) {
+ while (true) {
+ if (__s == __l1)
+ return __last1;
+ if (std::__invoke(__pred, std::__invoke(__proj1, *--__l1), std::__invoke(__proj2, *__l2)))
+ break;
+ }
+ _Iter1 __m1 = __l1;
+ _Iter2 __m2 = __l2;
+ while (true) {
+ if (__m2 == __first2)
+ return __m1;
+ // no need to check range on __m1 because __s guarantees we have enough source
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *--__m1), std::__invoke(*--__m2))) {
+ break;
+ }
+ }
+ }
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator1 __find_end_classic(
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _BinaryPredicate& __pred) {
+ auto __proj = __identity();
+ return std::__find_end_impl<_ClassicAlgPolicy>(
+ __first1,
+ __last1,
+ __first2,
+ __last2,
+ __pred,
+ __proj,
+ __proj,
+ typename iterator_traits<_ForwardIterator1>::iterator_category(),
+ typename iterator_traits<_ForwardIterator2>::iterator_category())
+ .first;
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator1 find_end(
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _BinaryPredicate __pred) {
+ return std::__find_end_classic(__first1, __last1, __first2, __last2, __pred);
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator1
+find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2, _ForwardIterator2 __last2) {
+ return std::find_end(__first1, __last1, __first2, __last2, __equal_to());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FIND_END_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/find_first_of.h b/libcxx/include/__cxx03/__algorithm/find_first_of.h
new file mode 100644
index 00000000000000..6b99f562f8804e
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/find_first_of.h
@@ -0,0 +1,55 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FIND_FIRST_OF_H
+#define _LIBCPP___ALGORITHM_FIND_FIRST_OF_H
+
+#include <__algorithm/comp.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator1 __find_first_of_ce(
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _BinaryPredicate&& __pred) {
+ for (; __first1 != __last1; ++__first1)
+ for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
+ if (__pred(*__first1, *__j))
+ return __first1;
+ return __last1;
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator1 find_first_of(
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _BinaryPredicate __pred) {
+ return std::__find_first_of_ce(__first1, __last1, __first2, __last2, __pred);
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator1 find_first_of(
+ _ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2, _ForwardIterator2 __last2) {
+ return std::__find_first_of_ce(__first1, __last1, __first2, __last2, __equal_to());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FIND_FIRST_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/find_if.h b/libcxx/include/__cxx03/__algorithm/find_if.h
new file mode 100644
index 00000000000000..22092d352b06e7
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/find_if.h
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FIND_IF_H
+#define _LIBCPP___ALGORITHM_FIND_IF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _InputIterator
+find_if(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ break;
+ return __first;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FIND_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/find_if_not.h b/libcxx/include/__cxx03/__algorithm/find_if_not.h
new file mode 100644
index 00000000000000..cc2001967f0c5a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/find_if_not.h
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FIND_IF_NOT_H
+#define _LIBCPP___ALGORITHM_FIND_IF_NOT_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _InputIterator
+find_if_not(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
+ for (; __first != __last; ++__first)
+ if (!__pred(*__first))
+ break;
+ return __first;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FIND_IF_NOT_H
diff --git a/libcxx/include/__cxx03/__algorithm/find_segment_if.h b/libcxx/include/__cxx03/__algorithm/find_segment_if.h
new file mode 100644
index 00000000000000..9d6064f3e283a6
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/find_segment_if.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FIND_SEGMENT_IF_H
+#define _LIBCPP___ALGORITHM_FIND_SEGMENT_IF_H
+
+#include <__config>
+#include <__iterator/segmented_iterator.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// __find_segment_if is a utility function for optimizing iteration over segmented iterators linearly.
+// [__first, __last) has to be a segmented range. __pred is expected to take a range of local iterators and the __proj.
+// It returns an iterator to the first element that satisfies the predicate, or a one-past-the-end iterator if there was
+// no match. __proj may be anything that should be passed to __pred, but is expected to be a projection to support
+// ranges algorithms, or __identity for classic algorithms.
+
+template <class _SegmentedIterator, class _Pred, class _Proj>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _SegmentedIterator
+__find_segment_if(_SegmentedIterator __first, _SegmentedIterator __last, _Pred __pred, _Proj& __proj) {
+ using _Traits = __segmented_iterator_traits<_SegmentedIterator>;
+
+ auto __sfirst = _Traits::__segment(__first);
+ auto __slast = _Traits::__segment(__last);
+
+ // We are in a single segment, so we might not be at the beginning or end
+ if (__sfirst == __slast)
+ return _Traits::__compose(__sfirst, __pred(_Traits::__local(__first), _Traits::__local(__last), __proj));
+
+ { // We have more than one segment. Iterate over the first segment, since we might not start at the beginning
+ auto __llast = _Traits::__end(__sfirst);
+ auto __liter = __pred(_Traits::__local(__first), __llast, __proj);
+ if (__liter != __llast)
+ return _Traits::__compose(__sfirst, __liter);
+ }
+ ++__sfirst;
+
+ // Iterate over the segments which are guaranteed to be completely in the range
+ while (__sfirst != __slast) {
+ auto __llast = _Traits::__end(__sfirst);
+ auto __liter = __pred(_Traits::__begin(__sfirst), _Traits::__end(__sfirst), __proj);
+ if (__liter != __llast)
+ return _Traits::__compose(__sfirst, __liter);
+ ++__sfirst;
+ }
+
+ // Iterate over the last segment
+ return _Traits::__compose(__sfirst, __pred(_Traits::__begin(__sfirst), _Traits::__local(__last), __proj));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FIND_SEGMENT_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/fold.h b/libcxx/include/__cxx03/__algorithm/fold.h
new file mode 100644
index 00000000000000..255658f5232499
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/fold.h
@@ -0,0 +1,128 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FOLD_H
+#define _LIBCPP___ALGORITHM_FOLD_H
+
+#include <__concepts/assignable.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/invocable.h>
+#include <__concepts/movable.h>
+#include <__config>
+#include <__functional/invoke.h>
+#include <__functional/reference_wrapper.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/invoke.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+namespace ranges {
+template <class _Ip, class _Tp>
+struct in_value_result {
+ _LIBCPP_NO_UNIQUE_ADDRESS _Ip in;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Tp value;
+
+ template <class _I2, class _T2>
+ requires convertible_to<const _Ip&, _I2> && convertible_to<const _Tp&, _T2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_value_result<_I2, _T2>() const& {
+ return {in, value};
+ }
+
+ template <class _I2, class _T2>
+ requires convertible_to<_Ip, _I2> && convertible_to<_Tp, _T2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_value_result<_I2, _T2>() && {
+ return {std::move(in), std::move(value)};
+ }
+};
+
+template <class _Ip, class _Tp>
+using fold_left_with_iter_result = in_value_result<_Ip, _Tp>;
+
+template <class _Fp, class _Tp, class _Ip, class _Rp, class _Up = decay_t<_Rp>>
+concept __indirectly_binary_left_foldable_impl =
+ convertible_to<_Rp, _Up> && //
+ movable<_Tp> && //
+ movable<_Up> && //
+ convertible_to<_Tp, _Up> && //
+ invocable<_Fp&, _Up, iter_reference_t<_Ip>> && //
+ assignable_from<_Up&, invoke_result_t<_Fp&, _Up, iter_reference_t<_Ip>>>;
+
+template <class _Fp, class _Tp, class _Ip>
+concept __indirectly_binary_left_foldable =
+ copy_constructible<_Fp> && //
+ invocable<_Fp&, _Tp, iter_reference_t<_Ip>> && //
+ __indirectly_binary_left_foldable_impl<_Fp, _Tp, _Ip, invoke_result_t<_Fp&, _Tp, iter_reference_t<_Ip>>>;
+
+struct __fold_left_with_iter {
+ template <input_iterator _Ip, sentinel_for<_Ip> _Sp, class _Tp, __indirectly_binary_left_foldable<_Tp, _Ip> _Fp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Ip __first, _Sp __last, _Tp __init, _Fp __f) {
+ using _Up = decay_t<invoke_result_t<_Fp&, _Tp, iter_reference_t<_Ip>>>;
+
+ if (__first == __last) {
+ return fold_left_with_iter_result<_Ip, _Up>{std::move(__first), _Up(std::move(__init))};
+ }
+
+ _Up __result = std::invoke(__f, std::move(__init), *__first);
+ for (++__first; __first != __last; ++__first) {
+ __result = std::invoke(__f, std::move(__result), *__first);
+ }
+
+ return fold_left_with_iter_result<_Ip, _Up>{std::move(__first), std::move(__result)};
+ }
+
+ template <input_range _Rp, class _Tp, __indirectly_binary_left_foldable<_Tp, iterator_t<_Rp>> _Fp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Rp&& __r, _Tp __init, _Fp __f) {
+ auto __result = operator()(ranges::begin(__r), ranges::end(__r), std::move(__init), std::ref(__f));
+
+ using _Up = decay_t<invoke_result_t<_Fp&, _Tp, range_reference_t<_Rp>>>;
+ return fold_left_with_iter_result<borrowed_iterator_t<_Rp>, _Up>{std::move(__result.in), std::move(__result.value)};
+ }
+};
+
+inline constexpr auto fold_left_with_iter = __fold_left_with_iter();
+
+struct __fold_left {
+ template <input_iterator _Ip, sentinel_for<_Ip> _Sp, class _Tp, __indirectly_binary_left_foldable<_Tp, _Ip> _Fp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Ip __first, _Sp __last, _Tp __init, _Fp __f) {
+ return fold_left_with_iter(std::move(__first), std::move(__last), std::move(__init), std::ref(__f)).value;
+ }
+
+ template <input_range _Rp, class _Tp, __indirectly_binary_left_foldable<_Tp, iterator_t<_Rp>> _Fp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Rp&& __r, _Tp __init, _Fp __f) {
+ return fold_left_with_iter(ranges::begin(__r), ranges::end(__r), std::move(__init), std::ref(__f)).value;
+ }
+};
+
+inline constexpr auto fold_left = __fold_left();
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_FOLD_H
diff --git a/libcxx/include/__cxx03/__algorithm/for_each.h b/libcxx/include/__cxx03/__algorithm/for_each.h
new file mode 100644
index 00000000000000..259e527f87f915
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/for_each.h
@@ -0,0 +1,57 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FOR_EACH_H
+#define _LIBCPP___ALGORITHM_FOR_EACH_H
+
+#include <__algorithm/for_each_segment.h>
+#include <__config>
+#include <__iterator/segmented_iterator.h>
+#include <__ranges/movable_box.h>
+#include <__type_traits/enable_if.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Function>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Function
+for_each(_InputIterator __first, _InputIterator __last, _Function __f) {
+ for (; __first != __last; ++__first)
+ __f(*__first);
+ return __f;
+}
+
+// __movable_box is available in C++20, but is actually a copyable-box, so optimization is only correct in C++23
+#if _LIBCPP_STD_VER >= 23
+template <class _SegmentedIterator, class _Function>
+ requires __is_segmented_iterator<_SegmentedIterator>::value
+_LIBCPP_HIDE_FROM_ABI constexpr _Function
+for_each(_SegmentedIterator __first, _SegmentedIterator __last, _Function __func) {
+ ranges::__movable_box<_Function> __wrapped_func(in_place, std::move(__func));
+ std::__for_each_segment(__first, __last, [&](auto __lfirst, auto __llast) {
+ __wrapped_func =
+ ranges::__movable_box<_Function>(in_place, std::for_each(__lfirst, __llast, std::move(*__wrapped_func)));
+ });
+ return std::move(*__wrapped_func);
+}
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_FOR_EACH_H
diff --git a/libcxx/include/__cxx03/__algorithm/for_each_n.h b/libcxx/include/__cxx03/__algorithm/for_each_n.h
new file mode 100644
index 00000000000000..fce380b49df3e0
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/for_each_n.h
@@ -0,0 +1,41 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FOR_EACH_N_H
+#define _LIBCPP___ALGORITHM_FOR_EACH_N_H
+
+#include <__config>
+#include <__utility/convert_to_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _InputIterator, class _Size, class _Function>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _InputIterator
+for_each_n(_InputIterator __first, _Size __orig_n, _Function __f) {
+ typedef decltype(std::__convert_to_integral(__orig_n)) _IntegralSize;
+ _IntegralSize __n = __orig_n;
+ while (__n > 0) {
+ __f(*__first);
+ ++__first;
+ --__n;
+ }
+ return __first;
+}
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FOR_EACH_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/for_each_segment.h b/libcxx/include/__cxx03/__algorithm/for_each_segment.h
new file mode 100644
index 00000000000000..93aa8259b2f7f2
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/for_each_segment.h
@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_FOR_EACH_SEGMENT_H
+#define _LIBCPP___ALGORITHM_FOR_EACH_SEGMENT_H
+
+#include <__config>
+#include <__iterator/segmented_iterator.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// __for_each_segment is a utility function for optimizing iterating over segmented iterators linearly.
+// __first and __last are expected to be a segmented range. __func is expected to take a range of local iterators.
+// Anything that is returned from __func is ignored.
+
+template <class _SegmentedIterator, class _Functor>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__for_each_segment(_SegmentedIterator __first, _SegmentedIterator __last, _Functor __func) {
+ using _Traits = __segmented_iterator_traits<_SegmentedIterator>;
+
+ auto __sfirst = _Traits::__segment(__first);
+ auto __slast = _Traits::__segment(__last);
+
+ // We are in a single segment, so we might not be at the beginning or end
+ if (__sfirst == __slast) {
+ __func(_Traits::__local(__first), _Traits::__local(__last));
+ return;
+ }
+
+ // We have more than one segment. Iterate over the first segment, since we might not start at the beginning
+ __func(_Traits::__local(__first), _Traits::__end(__sfirst));
+ ++__sfirst;
+ // iterate over the segments which are guaranteed to be completely in the range
+ while (__sfirst != __slast) {
+ __func(_Traits::__begin(__sfirst), _Traits::__end(__sfirst));
+ ++__sfirst;
+ }
+ // iterate over the last segment
+ __func(_Traits::__begin(__sfirst), _Traits::__local(__last));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FOR_EACH_SEGMENT_H
diff --git a/libcxx/include/__cxx03/__algorithm/generate.h b/libcxx/include/__cxx03/__algorithm/generate.h
new file mode 100644
index 00000000000000..c95b527402f5db
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/generate.h
@@ -0,0 +1,29 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_GENERATE_H
+#define _LIBCPP___ALGORITHM_GENERATE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Generator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+generate(_ForwardIterator __first, _ForwardIterator __last, _Generator __gen) {
+ for (; __first != __last; ++__first)
+ *__first = __gen();
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_GENERATE_H
diff --git a/libcxx/include/__cxx03/__algorithm/generate_n.h b/libcxx/include/__cxx03/__algorithm/generate_n.h
new file mode 100644
index 00000000000000..f36403fd0f94a9
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/generate_n.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_GENERATE_N_H
+#define _LIBCPP___ALGORITHM_GENERATE_N_H
+
+#include <__config>
+#include <__utility/convert_to_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _OutputIterator, class _Size, class _Generator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+generate_n(_OutputIterator __first, _Size __orig_n, _Generator __gen) {
+ typedef decltype(std::__convert_to_integral(__orig_n)) _IntegralSize;
+ _IntegralSize __n = __orig_n;
+ for (; __n > 0; ++__first, (void)--__n)
+ *__first = __gen();
+ return __first;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_GENERATE_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/half_positive.h b/libcxx/include/__cxx03/__algorithm/half_positive.h
new file mode 100644
index 00000000000000..ebda0da372369d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/half_positive.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_HALF_POSITIVE_H
+#define _LIBCPP___ALGORITHM_HALF_POSITIVE_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/make_unsigned.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Perform division by two quickly for positive integers (llvm.org/PR39129)
+
+template <typename _Integral, __enable_if_t<is_integral<_Integral>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Integral __half_positive(_Integral __value) {
+ return static_cast<_Integral>(static_cast<__make_unsigned_t<_Integral> >(__value) / 2);
+}
+
+template <typename _Tp, __enable_if_t<!is_integral<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp __half_positive(_Tp __value) {
+ return __value / 2;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_HALF_POSITIVE_H
diff --git a/libcxx/include/__cxx03/__algorithm/in_found_result.h b/libcxx/include/__cxx03/__algorithm/in_found_result.h
new file mode 100644
index 00000000000000..a67ae387974c0a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/in_found_result.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IN_FOUND_RESULT_H
+#define _LIBCPP___ALGORITHM_IN_FOUND_RESULT_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+template <class _InIter1>
+struct in_found_result {
+ _LIBCPP_NO_UNIQUE_ADDRESS _InIter1 in;
+ bool found;
+
+ template <class _InIter2>
+ requires convertible_to<const _InIter1&, _InIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_found_result<_InIter2>() const& {
+ return {in, found};
+ }
+
+ template <class _InIter2>
+ requires convertible_to<_InIter1, _InIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_found_result<_InIter2>() && {
+ return {std::move(in), found};
+ }
+};
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_IN_FOUND_RESULT_H
diff --git a/libcxx/include/__cxx03/__algorithm/in_fun_result.h b/libcxx/include/__cxx03/__algorithm/in_fun_result.h
new file mode 100644
index 00000000000000..a22069a9a8ddaa
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/in_fun_result.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IN_FUN_RESULT_H
+#define _LIBCPP___ALGORITHM_IN_FUN_RESULT_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <class _InIter1, class _Func1>
+struct in_fun_result {
+ _LIBCPP_NO_UNIQUE_ADDRESS _InIter1 in;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Func1 fun;
+
+ template <class _InIter2, class _Func2>
+ requires convertible_to<const _InIter1&, _InIter2> && convertible_to<const _Func1&, _Func2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_fun_result<_InIter2, _Func2>() const& {
+ return {in, fun};
+ }
+
+ template <class _InIter2, class _Func2>
+ requires convertible_to<_InIter1, _InIter2> && convertible_to<_Func1, _Func2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_fun_result<_InIter2, _Func2>() && {
+ return {std::move(in), std::move(fun)};
+ }
+};
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_IN_FUN_RESULT_H
diff --git a/libcxx/include/__cxx03/__algorithm/in_in_out_result.h b/libcxx/include/__cxx03/__algorithm/in_in_out_result.h
new file mode 100644
index 00000000000000..ba0380b5c68147
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/in_in_out_result.h
@@ -0,0 +1,59 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IN_IN_OUT_RESULT_H
+#define _LIBCPP___ALGORITHM_IN_IN_OUT_RESULT_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _InIter1, class _InIter2, class _OutIter1>
+struct in_in_out_result {
+ _LIBCPP_NO_UNIQUE_ADDRESS _InIter1 in1;
+ _LIBCPP_NO_UNIQUE_ADDRESS _InIter2 in2;
+ _LIBCPP_NO_UNIQUE_ADDRESS _OutIter1 out;
+
+ template <class _InIter3, class _InIter4, class _OutIter2>
+ requires convertible_to<const _InIter1&, _InIter3> && convertible_to<const _InIter2&, _InIter4> &&
+ convertible_to<const _OutIter1&, _OutIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_in_out_result<_InIter3, _InIter4, _OutIter2>() const& {
+ return {in1, in2, out};
+ }
+
+ template <class _InIter3, class _InIter4, class _OutIter2>
+ requires convertible_to<_InIter1, _InIter3> && convertible_to<_InIter2, _InIter4> &&
+ convertible_to<_OutIter1, _OutIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_in_out_result<_InIter3, _InIter4, _OutIter2>() && {
+ return {std::move(in1), std::move(in2), std::move(out)};
+ }
+};
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_IN_IN_OUT_RESULT_H
diff --git a/libcxx/include/__cxx03/__algorithm/in_in_result.h b/libcxx/include/__cxx03/__algorithm/in_in_result.h
new file mode 100644
index 00000000000000..994573fc70fd88
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/in_in_result.h
@@ -0,0 +1,56 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IN_IN_RESULT_H
+#define _LIBCPP___ALGORITHM_IN_IN_RESULT_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _InIter1, class _InIter2>
+struct in_in_result {
+ _LIBCPP_NO_UNIQUE_ADDRESS _InIter1 in1;
+ _LIBCPP_NO_UNIQUE_ADDRESS _InIter2 in2;
+
+ template <class _InIter3, class _InIter4>
+ requires convertible_to<const _InIter1&, _InIter3> && convertible_to<const _InIter2&, _InIter4>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_in_result<_InIter3, _InIter4>() const& {
+ return {in1, in2};
+ }
+
+ template <class _InIter3, class _InIter4>
+ requires convertible_to<_InIter1, _InIter3> && convertible_to<_InIter2, _InIter4>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_in_result<_InIter3, _InIter4>() && {
+ return {std::move(in1), std::move(in2)};
+ }
+};
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_IN_IN_RESULT_H
diff --git a/libcxx/include/__cxx03/__algorithm/in_out_out_result.h b/libcxx/include/__cxx03/__algorithm/in_out_out_result.h
new file mode 100644
index 00000000000000..8ceb452841a419
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/in_out_out_result.h
@@ -0,0 +1,57 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IN_OUT_OUT_RESULT_H
+#define _LIBCPP___ALGORITHM_IN_OUT_OUT_RESULT_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <class _InIter1, class _OutIter1, class _OutIter2>
+struct in_out_out_result {
+ _LIBCPP_NO_UNIQUE_ADDRESS _InIter1 in;
+ _LIBCPP_NO_UNIQUE_ADDRESS _OutIter1 out1;
+ _LIBCPP_NO_UNIQUE_ADDRESS _OutIter2 out2;
+
+ template <class _InIter2, class _OutIter3, class _OutIter4>
+ requires convertible_to<const _InIter1&, _InIter2> && convertible_to<const _OutIter1&, _OutIter3> &&
+ convertible_to<const _OutIter2&, _OutIter4>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_out_out_result<_InIter2, _OutIter3, _OutIter4>() const& {
+ return {in, out1, out2};
+ }
+
+ template <class _InIter2, class _OutIter3, class _OutIter4>
+ requires convertible_to<_InIter1, _InIter2> && convertible_to<_OutIter1, _OutIter3> &&
+ convertible_to<_OutIter2, _OutIter4>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_out_out_result<_InIter2, _OutIter3, _OutIter4>() && {
+ return {std::move(in), std::move(out1), std::move(out2)};
+ }
+};
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_IN_OUT_OUT_RESULT_H
diff --git a/libcxx/include/__cxx03/__algorithm/in_out_result.h b/libcxx/include/__cxx03/__algorithm/in_out_result.h
new file mode 100644
index 00000000000000..a7a986cf8e6c09
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/in_out_result.h
@@ -0,0 +1,56 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IN_OUT_RESULT_H
+#define _LIBCPP___ALGORITHM_IN_OUT_RESULT_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _InIter1, class _OutIter1>
+struct in_out_result {
+ _LIBCPP_NO_UNIQUE_ADDRESS _InIter1 in;
+ _LIBCPP_NO_UNIQUE_ADDRESS _OutIter1 out;
+
+ template <class _InIter2, class _OutIter2>
+ requires convertible_to<const _InIter1&, _InIter2> && convertible_to<const _OutIter1&, _OutIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_out_result<_InIter2, _OutIter2>() const& {
+ return {in, out};
+ }
+
+ template <class _InIter2, class _OutIter2>
+ requires convertible_to<_InIter1, _InIter2> && convertible_to<_OutIter1, _OutIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator in_out_result<_InIter2, _OutIter2>() && {
+ return {std::move(in), std::move(out)};
+ }
+};
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_IN_OUT_RESULT_H
diff --git a/libcxx/include/__cxx03/__algorithm/includes.h b/libcxx/include/__cxx03/__algorithm/includes.h
new file mode 100644
index 00000000000000..62af03c3742608
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/includes.h
@@ -0,0 +1,79 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_INCLUDES_H
+#define _LIBCPP___ALGORITHM_INCLUDES_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_callable.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Comp, class _Proj1, class _Proj2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __includes(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Comp&& __comp,
+ _Proj1&& __proj1,
+ _Proj2&& __proj2) {
+ for (; __first2 != __last2; ++__first1) {
+ if (__first1 == __last1 ||
+ std::__invoke(__comp, std::__invoke(__proj2, *__first2), std::__invoke(__proj1, *__first1)))
+ return false;
+ if (!std::__invoke(__comp, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ ++__first2;
+ }
+ return true;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+includes(_InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _Compare __comp) {
+ static_assert(
+ __is_callable<_Compare, decltype(*__first1), decltype(*__first2)>::value, "Comparator has to be callable");
+
+ return std::__includes(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ static_cast<__comp_ref_type<_Compare> >(__comp),
+ __identity(),
+ __identity());
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2) {
+ return std::includes(std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_INCLUDES_H
diff --git a/libcxx/include/__cxx03/__algorithm/inplace_merge.h b/libcxx/include/__cxx03/__algorithm/inplace_merge.h
new file mode 100644
index 00000000000000..a6bcc66a2fa47a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/inplace_merge.h
@@ -0,0 +1,240 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_INPLACE_MERGE_H
+#define _LIBCPP___ALGORITHM_INPLACE_MERGE_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/lower_bound.h>
+#include <__algorithm/min.h>
+#include <__algorithm/move.h>
+#include <__algorithm/rotate.h>
+#include <__algorithm/upper_bound.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__iterator/advance.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__memory/destruct_n.h>
+#include <__memory/temporary_buffer.h>
+#include <__memory/unique_ptr.h>
+#include <__utility/pair.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Predicate>
+class __invert // invert the sense of a comparison
+{
+private:
+ _Predicate __p_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __invert() {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __invert(_Predicate __p) : __p_(__p) {}
+
+ template <class _T1>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _T1& __x) {
+ return !__p_(__x);
+ }
+
+ template <class _T1, class _T2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _T1& __x, const _T2& __y) {
+ return __p_(__y, __x);
+ }
+};
+
+template <class _AlgPolicy,
+ class _Compare,
+ class _InputIterator1,
+ class _Sent1,
+ class _InputIterator2,
+ class _Sent2,
+ class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI void __half_inplace_merge(
+ _InputIterator1 __first1,
+ _Sent1 __last1,
+ _InputIterator2 __first2,
+ _Sent2 __last2,
+ _OutputIterator __result,
+ _Compare&& __comp) {
+ for (; __first1 != __last1; ++__result) {
+ if (__first2 == __last2) {
+ std::__move<_AlgPolicy>(__first1, __last1, __result);
+ return;
+ }
+
+ if (__comp(*__first2, *__first1)) {
+ *__result = _IterOps<_AlgPolicy>::__iter_move(__first2);
+ ++__first2;
+ } else {
+ *__result = _IterOps<_AlgPolicy>::__iter_move(__first1);
+ ++__first1;
+ }
+ }
+ // __first2 through __last2 are already in the right spot.
+}
+
+template <class _AlgPolicy, class _Compare, class _BidirectionalIterator>
+_LIBCPP_HIDE_FROM_ABI void __buffered_inplace_merge(
+ _BidirectionalIterator __first,
+ _BidirectionalIterator __middle,
+ _BidirectionalIterator __last,
+ _Compare&& __comp,
+ typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
+ typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
+ typename iterator_traits<_BidirectionalIterator>::value_type* __buff) {
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
+ if (__len1 <= __len2) {
+ value_type* __p = __buff;
+ for (_BidirectionalIterator __i = __first; __i != __middle;
+ __d.template __incr<value_type>(), (void)++__i, (void)++__p)
+ ::new ((void*)__p) value_type(_IterOps<_AlgPolicy>::__iter_move(__i));
+ std::__half_inplace_merge<_AlgPolicy>(__buff, __p, __middle, __last, __first, __comp);
+ } else {
+ value_type* __p = __buff;
+ for (_BidirectionalIterator __i = __middle; __i != __last;
+ __d.template __incr<value_type>(), (void)++__i, (void)++__p)
+ ::new ((void*)__p) value_type(_IterOps<_AlgPolicy>::__iter_move(__i));
+ typedef reverse_iterator<_BidirectionalIterator> _RBi;
+ typedef reverse_iterator<value_type*> _Rv;
+ typedef __invert<_Compare> _Inverted;
+ std::__half_inplace_merge<_AlgPolicy>(
+ _Rv(__p), _Rv(__buff), _RBi(__middle), _RBi(__first), _RBi(__last), _Inverted(__comp));
+ }
+}
+
+template <class _AlgPolicy, class _Compare, class _BidirectionalIterator>
+void __inplace_merge(
+ _BidirectionalIterator __first,
+ _BidirectionalIterator __middle,
+ _BidirectionalIterator __last,
+ _Compare&& __comp,
+ typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
+ typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
+ typename iterator_traits<_BidirectionalIterator>::value_type* __buff,
+ ptrdiff_t __buff_size) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
+ while (true) {
+ // if __middle == __last, we're done
+ if (__len2 == 0)
+ return;
+ if (__len1 <= __buff_size || __len2 <= __buff_size)
+ return std::__buffered_inplace_merge<_AlgPolicy>(__first, __middle, __last, __comp, __len1, __len2, __buff);
+ // shrink [__first, __middle) as much as possible (with no moves), returning if it shrinks to 0
+ for (; true; ++__first, (void)--__len1) {
+ if (__len1 == 0)
+ return;
+ if (__comp(*__middle, *__first))
+ break;
+ }
+ // __first < __middle < __last
+ // *__first > *__middle
+ // partition [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last) such that
+ // all elements in:
+ // [__first, __m1) <= [__middle, __m2)
+ // [__middle, __m2) < [__m1, __middle)
+ // [__m1, __middle) <= [__m2, __last)
+ // and __m1 or __m2 is in the middle of its range
+ _BidirectionalIterator __m1; // "median" of [__first, __middle)
+ _BidirectionalIterator __m2; // "median" of [__middle, __last)
+ difference_type __len11; // distance(__first, __m1)
+ difference_type __len21; // distance(__middle, __m2)
+ // binary search smaller range
+ if (__len1 < __len2) { // __len >= 1, __len2 >= 2
+ __len21 = __len2 / 2;
+ __m2 = __middle;
+ _Ops::advance(__m2, __len21);
+ __m1 = std::__upper_bound<_AlgPolicy>(__first, __middle, *__m2, __comp, std::__identity());
+ __len11 = _Ops::distance(__first, __m1);
+ } else {
+ if (__len1 == 1) { // __len1 >= __len2 && __len2 > 0, therefore __len2 == 1
+ // It is known *__first > *__middle
+ _Ops::iter_swap(__first, __middle);
+ return;
+ }
+ // __len1 >= 2, __len2 >= 1
+ __len11 = __len1 / 2;
+ __m1 = __first;
+ _Ops::advance(__m1, __len11);
+ __m2 = std::lower_bound(__middle, __last, *__m1, __comp);
+ __len21 = _Ops::distance(__middle, __m2);
+ }
+ difference_type __len12 = __len1 - __len11; // distance(__m1, __middle)
+ difference_type __len22 = __len2 - __len21; // distance(__m2, __last)
+ // [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last)
+ // swap middle two partitions
+ __middle = std::__rotate<_AlgPolicy>(__m1, __middle, __m2).first;
+ // __len12 and __len21 now have swapped meanings
+ // merge smaller range with recursive call and larger with tail recursion elimination
+ if (__len11 + __len21 < __len12 + __len22) {
+ std::__inplace_merge<_AlgPolicy>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
+ __first = __middle;
+ __middle = __m2;
+ __len1 = __len12;
+ __len2 = __len22;
+ } else {
+ std::__inplace_merge<_AlgPolicy>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
+ __last = __middle;
+ __middle = __m1;
+ __len1 = __len11;
+ __len2 = __len21;
+ }
+ }
+}
+
+template <class _AlgPolicy, class _BidirectionalIterator, class _Compare>
+_LIBCPP_HIDE_FROM_ABI void __inplace_merge(
+ _BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last, _Compare&& __comp) {
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
+ difference_type __len1 = _IterOps<_AlgPolicy>::distance(__first, __middle);
+ difference_type __len2 = _IterOps<_AlgPolicy>::distance(__middle, __last);
+ difference_type __buf_size = std::min(__len1, __len2);
+ // TODO: Remove the use of std::get_temporary_buffer
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ pair<value_type*, ptrdiff_t> __buf = std::get_temporary_buffer<value_type>(__buf_size);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ unique_ptr<value_type, __return_temporary_buffer> __h(__buf.first);
+ return std::__inplace_merge<_AlgPolicy>(
+ std::move(__first), std::move(__middle), std::move(__last), __comp, __len1, __len2, __buf.first, __buf.second);
+}
+
+template <class _BidirectionalIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI void inplace_merge(
+ _BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last, _Compare __comp) {
+ std::__inplace_merge<_ClassicAlgPolicy>(
+ std::move(__first), std::move(__middle), std::move(__last), static_cast<__comp_ref_type<_Compare> >(__comp));
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_HIDE_FROM_ABI void
+inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last) {
+ std::inplace_merge(std::move(__first), std::move(__middle), std::move(__last), __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_INPLACE_MERGE_H
diff --git a/libcxx/include/__cxx03/__algorithm/is_heap.h b/libcxx/include/__cxx03/__algorithm/is_heap.h
new file mode 100644
index 00000000000000..c589b804a5dc08
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/is_heap.h
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IS_HEAP_H
+#define _LIBCPP___ALGORITHM_IS_HEAP_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/is_heap_until.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RandomAccessIterator, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ return std::__is_heap_until(__first, __last, static_cast<__comp_ref_type<_Compare> >(__comp)) == __last;
+}
+
+template <class _RandomAccessIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ return std::is_heap(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_IS_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/is_heap_until.h b/libcxx/include/__cxx03/__algorithm/is_heap_until.h
new file mode 100644
index 00000000000000..a174f2453cfcc0
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/is_heap_until.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IS_HEAP_UNTIL_H
+#define _LIBCPP___ALGORITHM_IS_HEAP_UNTIL_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Compare, class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _RandomAccessIterator
+__is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare&& __comp) {
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ difference_type __len = __last - __first;
+ difference_type __p = 0;
+ difference_type __c = 1;
+ _RandomAccessIterator __pp = __first;
+ while (__c < __len) {
+ _RandomAccessIterator __cp = __first + __c;
+ if (__comp(*__pp, *__cp))
+ return __cp;
+ ++__c;
+ ++__cp;
+ if (__c == __len)
+ return __last;
+ if (__comp(*__pp, *__cp))
+ return __cp;
+ ++__p;
+ ++__pp;
+ __c = 2 * __p + 1;
+ }
+ return __last;
+}
+
+template <class _RandomAccessIterator, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _RandomAccessIterator
+is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ return std::__is_heap_until(__first, __last, static_cast<__comp_ref_type<_Compare> >(__comp));
+}
+
+template <class _RandomAccessIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _RandomAccessIterator
+is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ return std::__is_heap_until(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_IS_HEAP_UNTIL_H
diff --git a/libcxx/include/__cxx03/__algorithm/is_partitioned.h b/libcxx/include/__cxx03/__algorithm/is_partitioned.h
new file mode 100644
index 00000000000000..1f7c8b0b267e75
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/is_partitioned.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IS_PARTITIONED_H
+#define _LIBCPP___ALGORITHM_IS_PARTITIONED_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+is_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
+ for (; __first != __last; ++__first)
+ if (!__pred(*__first))
+ break;
+ if (__first == __last)
+ return true;
+ ++__first;
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ return false;
+ return true;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_IS_PARTITIONED_H
diff --git a/libcxx/include/__cxx03/__algorithm/is_permutation.h b/libcxx/include/__cxx03/__algorithm/is_permutation.h
new file mode 100644
index 00000000000000..2ddfb32a212bbb
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/is_permutation.h
@@ -0,0 +1,308 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IS_PERMUTATION_H
+#define _LIBCPP___ALGORITHM_IS_PERMUTATION_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__type_traits/is_callable.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class = void>
+struct _ConstTimeDistance : false_type {};
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Iter1, class _Sent1, class _Iter2, class _Sent2>
+struct _ConstTimeDistance<_Iter1,
+ _Sent1,
+ _Iter2,
+ _Sent2,
+ __enable_if_t< sized_sentinel_for<_Sent1, _Iter1> && sized_sentinel_for<_Sent2, _Iter2> >>
+ : true_type {};
+
+#else
+
+template <class _Iter1, class _Iter2>
+struct _ConstTimeDistance<
+ _Iter1,
+ _Iter1,
+ _Iter2,
+ _Iter2,
+ __enable_if_t< is_same<typename iterator_traits<_Iter1>::iterator_category, random_access_iterator_tag>::value &&
+ is_same<typename iterator_traits<_Iter2>::iterator_category, random_access_iterator_tag>::value > >
+ : true_type {};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+// Internal functions
+
+// For each element in [f1, l1) see if there are the same number of equal elements in [f2, l2)
+template <class _AlgPolicy,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Proj1,
+ class _Proj2,
+ class _Pred>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __is_permutation_impl(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred&& __pred,
+ _Proj1&& __proj1,
+ _Proj2&& __proj2) {
+ using _D1 = __iter_diff_t<_Iter1>;
+
+ for (auto __i = __first1; __i != __last1; ++__i) {
+ // Have we already counted the number of *__i in [f1, l1)?
+ auto __match = __first1;
+ for (; __match != __i; ++__match) {
+ if (std::__invoke(__pred, std::__invoke(__proj1, *__match), std::__invoke(__proj1, *__i)))
+ break;
+ }
+
+ if (__match == __i) {
+ // Count number of *__i in [f2, l2)
+ _D1 __c2 = 0;
+ for (auto __j = __first2; __j != __last2; ++__j) {
+ if (std::__invoke(__pred, std::__invoke(__proj1, *__i), std::__invoke(__proj2, *__j)))
+ ++__c2;
+ }
+ if (__c2 == 0)
+ return false;
+
+ // Count number of *__i in [__i, l1) (we can start with 1)
+ _D1 __c1 = 1;
+ for (auto __j = _IterOps<_AlgPolicy>::next(__i); __j != __last1; ++__j) {
+ if (std::__invoke(__pred, std::__invoke(__proj1, *__i), std::__invoke(__proj1, *__j)))
+ ++__c1;
+ }
+ if (__c1 != __c2)
+ return false;
+ }
+ }
+
+ return true;
+}
+
+// 2+1 iterators, predicate. Not used by range algorithms.
+template <class _AlgPolicy, class _ForwardIterator1, class _Sentinel1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __is_permutation(
+ _ForwardIterator1 __first1, _Sentinel1 __last1, _ForwardIterator2 __first2, _BinaryPredicate&& __pred) {
+ // Shorten sequences as much as possible by lopping of any equal prefix.
+ for (; __first1 != __last1; ++__first1, (void)++__first2) {
+ if (!__pred(*__first1, *__first2))
+ break;
+ }
+
+ if (__first1 == __last1)
+ return true;
+
+ // __first1 != __last1 && *__first1 != *__first2
+ using _D1 = __iter_diff_t<_ForwardIterator1>;
+ _D1 __l1 = _IterOps<_AlgPolicy>::distance(__first1, __last1);
+ if (__l1 == _D1(1))
+ return false;
+ auto __last2 = _IterOps<_AlgPolicy>::next(__first2, __l1);
+
+ return std::__is_permutation_impl<_AlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ __pred,
+ __identity(),
+ __identity());
+}
+
+// 2+2 iterators, predicate, non-constant time `distance`.
+template <class _AlgPolicy,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Proj1,
+ class _Proj2,
+ class _Pred>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __is_permutation(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred&& __pred,
+ _Proj1&& __proj1,
+ _Proj2&& __proj2,
+ /*_ConstTimeDistance=*/false_type) {
+ // Shorten sequences as much as possible by lopping of any equal prefix.
+ while (__first1 != __last1 && __first2 != __last2) {
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ break;
+ ++__first1;
+ ++__first2;
+ }
+
+ if (__first1 == __last1)
+ return __first2 == __last2;
+ if (__first2 == __last2) // Second range is shorter
+ return false;
+
+ using _D1 = __iter_diff_t<_Iter1>;
+ _D1 __l1 = _IterOps<_AlgPolicy>::distance(__first1, __last1);
+
+ using _D2 = __iter_diff_t<_Iter2>;
+ _D2 __l2 = _IterOps<_AlgPolicy>::distance(__first2, __last2);
+ if (__l1 != __l2)
+ return false;
+
+ return std::__is_permutation_impl<_AlgPolicy>(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
+}
+
+// 2+2 iterators, predicate, specialization for constant-time `distance` call.
+template <class _AlgPolicy,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Proj1,
+ class _Proj2,
+ class _Pred>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __is_permutation(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred&& __pred,
+ _Proj1&& __proj1,
+ _Proj2&& __proj2,
+ /*_ConstTimeDistance=*/true_type) {
+ if (std::distance(__first1, __last1) != std::distance(__first2, __last2))
+ return false;
+ return std::__is_permutation<_AlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ __pred,
+ __proj1,
+ __proj2,
+ /*_ConstTimeDistance=*/false_type());
+}
+
+// 2+2 iterators, predicate
+template <class _AlgPolicy,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Proj1,
+ class _Proj2,
+ class _Pred>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __is_permutation(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred&& __pred,
+ _Proj1&& __proj1,
+ _Proj2&& __proj2) {
+ return std::__is_permutation<_AlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ __pred,
+ __proj1,
+ __proj2,
+ _ConstTimeDistance<_Iter1, _Sent1, _Iter2, _Sent2>());
+}
+
+// Public interface
+
+// 2+1 iterators, predicate
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool is_permutation(
+ _ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2, _BinaryPredicate __pred) {
+ static_assert(__is_callable<_BinaryPredicate, decltype(*__first1), decltype(*__first2)>::value,
+ "The predicate has to be callable");
+
+ return std::__is_permutation<_ClassicAlgPolicy>(std::move(__first1), std::move(__last1), std::move(__first2), __pred);
+}
+
+// 2+1 iterators
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2) {
+ return std::is_permutation(__first1, __last1, __first2, __equal_to());
+}
+
+#if _LIBCPP_STD_VER >= 14
+
+// 2+2 iterators
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool is_permutation(
+ _ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2, _ForwardIterator2 __last2) {
+ return std::__is_permutation<_ClassicAlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ __equal_to(),
+ __identity(),
+ __identity());
+}
+
+// 2+2 iterators, predicate
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool is_permutation(
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _BinaryPredicate __pred) {
+ static_assert(__is_callable<_BinaryPredicate, decltype(*__first1), decltype(*__first2)>::value,
+ "The predicate has to be callable");
+
+ return std::__is_permutation<_ClassicAlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ __pred,
+ __identity(),
+ __identity());
+}
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_IS_PERMUTATION_H
diff --git a/libcxx/include/__cxx03/__algorithm/is_sorted.h b/libcxx/include/__cxx03/__algorithm/is_sorted.h
new file mode 100644
index 00000000000000..3befb1ac9c26a6
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/is_sorted.h
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IS_SORTED_H
+#define _LIBCPP___ALGORITHM_IS_SORTED_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/is_sorted_until.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+is_sorted(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
+ return std::__is_sorted_until<__comp_ref_type<_Compare> >(__first, __last, __comp) == __last;
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+is_sorted(_ForwardIterator __first, _ForwardIterator __last) {
+ return std::is_sorted(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_IS_SORTED_H
diff --git a/libcxx/include/__cxx03/__algorithm/is_sorted_until.h b/libcxx/include/__cxx03/__algorithm/is_sorted_until.h
new file mode 100644
index 00000000000000..53a49f00de31e8
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/is_sorted_until.h
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_IS_SORTED_UNTIL_H
+#define _LIBCPP___ALGORITHM_IS_SORTED_UNTIL_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Compare, class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+__is_sorted_until(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
+ if (__first != __last) {
+ _ForwardIterator __i = __first;
+ while (++__i != __last) {
+ if (__comp(*__i, *__first))
+ return __i;
+ __first = __i;
+ }
+ }
+ return __last;
+}
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+is_sorted_until(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
+ return std::__is_sorted_until<__comp_ref_type<_Compare> >(__first, __last, __comp);
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+is_sorted_until(_ForwardIterator __first, _ForwardIterator __last) {
+ return std::is_sorted_until(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_IS_SORTED_UNTIL_H
diff --git a/libcxx/include/__cxx03/__algorithm/iter_swap.h b/libcxx/include/__cxx03/__algorithm/iter_swap.h
new file mode 100644
index 00000000000000..a1412e5d8720be
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/iter_swap.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_ITER_SWAP_H
+#define _LIBCPP___ALGORITHM_ITER_SWAP_H
+
+#include <__config>
+#include <__utility/declval.h>
+#include <__utility/swap.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
+ // _NOEXCEPT_(_NOEXCEPT_(swap(*__a, *__b)))
+ _NOEXCEPT_(_NOEXCEPT_(swap(*std::declval<_ForwardIterator1>(), *std::declval<_ForwardIterator2>()))) {
+ swap(*__a, *__b);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_ITER_SWAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/iterator_operations.h b/libcxx/include/__cxx03/__algorithm/iterator_operations.h
new file mode 100644
index 00000000000000..8ced989233bc48
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/iterator_operations.h
@@ -0,0 +1,223 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_ITERATOR_OPERATIONS_H
+#define _LIBCPP___ALGORITHM_ITERATOR_OPERATIONS_H
+
+#include <__algorithm/iter_swap.h>
+#include <__algorithm/ranges_iterator_concept.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/advance.h>
+#include <__iterator/distance.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/prev.h>
+#include <__iterator/readable_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy>
+struct _IterOps;
+
+#if _LIBCPP_STD_VER >= 20
+struct _RangeAlgPolicy {};
+
+template <>
+struct _IterOps<_RangeAlgPolicy> {
+ template <class _Iter>
+ using __value_type = iter_value_t<_Iter>;
+
+ template <class _Iter>
+ using __iterator_category = ranges::__iterator_concept<_Iter>;
+
+ template <class _Iter>
+ using __difference_type = iter_difference_t<_Iter>;
+
+ static constexpr auto advance = ranges::advance;
+ static constexpr auto distance = ranges::distance;
+ static constexpr auto __iter_move = ranges::iter_move;
+ static constexpr auto iter_swap = ranges::iter_swap;
+ static constexpr auto next = ranges::next;
+ static constexpr auto prev = ranges::prev;
+ static constexpr auto __advance_to = ranges::advance;
+};
+
+#endif
+
+struct _ClassicAlgPolicy {};
+
+template <>
+struct _IterOps<_ClassicAlgPolicy> {
+ template <class _Iter>
+ using __value_type = typename iterator_traits<_Iter>::value_type;
+
+ template <class _Iter>
+ using __iterator_category = typename iterator_traits<_Iter>::iterator_category;
+
+ template <class _Iter>
+ using __difference_type = typename iterator_traits<_Iter>::difference_type;
+
+ // advance
+ template <class _Iter, class _Distance>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static void advance(_Iter& __iter, _Distance __count) {
+ std::advance(__iter, __count);
+ }
+
+ // distance
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static typename iterator_traits<_Iter>::difference_type
+ distance(_Iter __first, _Iter __last) {
+ return std::distance(__first, __last);
+ }
+
+ template <class _Iter>
+ using __deref_t = decltype(*std::declval<_Iter&>());
+
+ template <class _Iter>
+ using __move_t = decltype(std::move(*std::declval<_Iter&>()));
+
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static void __validate_iter_reference() {
+ static_assert(
+ is_same<__deref_t<_Iter>, typename iterator_traits<__remove_cvref_t<_Iter> >::reference>::value,
+ "It looks like your iterator's `iterator_traits<It>::reference` does not match the return type of "
+ "dereferencing the iterator, i.e., calling `*it`. This is undefined behavior according to [input.iterators] "
+ "and can lead to dangling reference issues at runtime, so we are flagging this.");
+ }
+
+ // iter_move
+ template <class _Iter, __enable_if_t<is_reference<__deref_t<_Iter> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static
+ // If the result of dereferencing `_Iter` is a reference type, deduce the result of calling `std::move` on it.
+ // Note that the C++03 mode doesn't support `decltype(auto)` as the return type.
+ __move_t<_Iter>
+ __iter_move(_Iter&& __i) {
+ __validate_iter_reference<_Iter>();
+
+ return std::move(*std::forward<_Iter>(__i));
+ }
+
+ template <class _Iter, __enable_if_t<!is_reference<__deref_t<_Iter> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static
+ // If the result of dereferencing `_Iter` is a value type, deduce the return value of this function to also be a
+ // value -- otherwise, after `operator*` returns a temporary, this function would return a dangling reference to
+ // that temporary. Note that the C++03 mode doesn't support `auto` as the return type.
+ __deref_t<_Iter>
+ __iter_move(_Iter&& __i) {
+ __validate_iter_reference<_Iter>();
+
+ return *std::forward<_Iter>(__i);
+ }
+
+ // iter_swap
+ template <class _Iter1, class _Iter2>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static void iter_swap(_Iter1&& __a, _Iter2&& __b) {
+ std::iter_swap(std::forward<_Iter1>(__a), std::forward<_Iter2>(__b));
+ }
+
+ // next
+ template <class _Iterator>
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX14 _Iterator next(_Iterator, _Iterator __last) {
+ return __last;
+ }
+
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX14 __remove_cvref_t<_Iter>
+ next(_Iter&& __it, typename iterator_traits<__remove_cvref_t<_Iter> >::difference_type __n = 1) {
+ return std::next(std::forward<_Iter>(__it), __n);
+ }
+
+ // prev
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX14 __remove_cvref_t<_Iter>
+ prev(_Iter&& __iter, typename iterator_traits<__remove_cvref_t<_Iter> >::difference_type __n = 1) {
+ return std::prev(std::forward<_Iter>(__iter), __n);
+ }
+
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX14 void __advance_to(_Iter& __first, _Iter __last) {
+ __first = __last;
+ }
+
+ // advance with sentinel, a la std::ranges::advance
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static __difference_type<_Iter>
+ __advance_to(_Iter& __iter, __difference_type<_Iter> __count, const _Iter& __sentinel) {
+ return _IterOps::__advance_to(__iter, __count, __sentinel, typename iterator_traits<_Iter>::iterator_category());
+ }
+
+private:
+ // advance with sentinel, a la std::ranges::advance -- InputIterator specialization
+ template <class _InputIter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static __difference_type<_InputIter> __advance_to(
+ _InputIter& __iter, __difference_type<_InputIter> __count, const _InputIter& __sentinel, input_iterator_tag) {
+ __difference_type<_InputIter> __dist = 0;
+ for (; __dist < __count && __iter != __sentinel; ++__dist)
+ ++__iter;
+ return __count - __dist;
+ }
+
+ // advance with sentinel, a la std::ranges::advance -- BidirectionalIterator specialization
+ template <class _BiDirIter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static __difference_type<_BiDirIter>
+ __advance_to(_BiDirIter& __iter,
+ __difference_type<_BiDirIter> __count,
+ const _BiDirIter& __sentinel,
+ bidirectional_iterator_tag) {
+ __difference_type<_BiDirIter> __dist = 0;
+ if (__count >= 0)
+ for (; __dist < __count && __iter != __sentinel; ++__dist)
+ ++__iter;
+ else
+ for (__count = -__count; __dist < __count && __iter != __sentinel; ++__dist)
+ --__iter;
+ return __count - __dist;
+ }
+
+ // advance with sentinel, a la std::ranges::advance -- RandomIterator specialization
+ template <class _RandIter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static __difference_type<_RandIter>
+ __advance_to(_RandIter& __iter,
+ __difference_type<_RandIter> __count,
+ const _RandIter& __sentinel,
+ random_access_iterator_tag) {
+ auto __dist = _IterOps::distance(__iter, __sentinel);
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(
+ __count == 0 || (__dist < 0) == (__count < 0), "__sentinel must precede __iter when __count < 0");
+ if (__count < 0)
+ __dist = __dist > __count ? __dist : __count;
+ else
+ __dist = __dist < __count ? __dist : __count;
+ __iter += __dist;
+ return __count - __dist;
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_ITERATOR_OPERATIONS_H
diff --git a/libcxx/include/__cxx03/__algorithm/lexicographical_compare.h b/libcxx/include/__cxx03/__algorithm/lexicographical_compare.h
new file mode 100644
index 00000000000000..edc29e269c88ca
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/lexicographical_compare.h
@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_H
+#define _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Compare, class _InputIterator1, class _InputIterator2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __lexicographical_compare(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _Compare __comp) {
+ for (; __first2 != __last2; ++__first1, (void)++__first2) {
+ if (__first1 == __last1 || __comp(*__first1, *__first2))
+ return true;
+ if (__comp(*__first2, *__first1))
+ return false;
+ }
+ return false;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool lexicographical_compare(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _Compare __comp) {
+ return std::__lexicographical_compare<__comp_ref_type<_Compare> >(__first1, __last1, __first2, __last2, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool lexicographical_compare(
+ _InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2) {
+ return std::lexicographical_compare(__first1, __last1, __first2, __last2, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_H
diff --git a/libcxx/include/__cxx03/__algorithm/lexicographical_compare_three_way.h b/libcxx/include/__cxx03/__algorithm/lexicographical_compare_three_way.h
new file mode 100644
index 00000000000000..a5872e90cf8d29
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/lexicographical_compare_three_way.h
@@ -0,0 +1,125 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_THREE_WAY_H
+#define _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_THREE_WAY_H
+
+#include <__algorithm/min.h>
+#include <__algorithm/three_way_comp_ref_type.h>
+#include <__compare/compare_three_way.h>
+#include <__compare/ordering.h>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// Fast path for random access iterators which computes the number of loop iterations up-front and
+// then skips the iterator comparisons inside the loop.
+template <class _InputIterator1, class _InputIterator2, class _Cmp>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __lexicographical_compare_three_way_fast_path(
+ _InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2, _Cmp& __comp)
+ -> decltype(__comp(*__first1, *__first2)) {
+ static_assert(
+ signed_integral<__iter_diff_t<_InputIterator1>>, "Using a non-integral difference_type is undefined behavior.");
+ static_assert(
+ signed_integral<__iter_diff_t<_InputIterator2>>, "Using a non-integral difference_type is undefined behavior.");
+
+ using _Len1 = __iter_diff_t<_InputIterator1>;
+ using _Len2 = __iter_diff_t<_InputIterator2>;
+ using _Common = common_type_t<_Len1, _Len2>;
+
+ _Len1 __len1 = __last1 - __first1;
+ _Len2 __len2 = __last2 - __first2;
+ _Common __min_len = std::min<_Common>(__len1, __len2);
+
+ for (_Common __i = 0; __i < __min_len; ++__i) {
+ auto __c = __comp(*__first1, *__first2);
+ if (__c != 0) {
+ return __c;
+ }
+ ++__first1;
+ ++__first2;
+ }
+
+ return __len1 <=> __len2;
+}
+
+// Unoptimized implementation which compares the iterators against the end in every loop iteration
+template <class _InputIterator1, class _InputIterator2, class _Cmp>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __lexicographical_compare_three_way_slow_path(
+ _InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2, _Cmp& __comp)
+ -> decltype(__comp(*__first1, *__first2)) {
+ while (true) {
+ bool __exhausted1 = __first1 == __last1;
+ bool __exhausted2 = __first2 == __last2;
+
+ if (__exhausted1 || __exhausted2) {
+ if (!__exhausted1)
+ return strong_ordering::greater;
+ if (!__exhausted2)
+ return strong_ordering::less;
+ return strong_ordering::equal;
+ }
+
+ auto __c = __comp(*__first1, *__first2);
+ if (__c != 0) {
+ return __c;
+ }
+
+ ++__first1;
+ ++__first2;
+ }
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Cmp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto lexicographical_compare_three_way(
+ _InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2, _Cmp __comp)
+ -> decltype(__comp(*__first1, *__first2)) {
+ static_assert(__comparison_category<decltype(__comp(*__first1, *__first2))>,
+ "The comparator passed to lexicographical_compare_three_way must return a comparison category type.");
+ static_assert(std::is_copy_constructible_v<_InputIterator1>, "Iterators must be copy constructible.");
+ static_assert(std::is_copy_constructible_v<_InputIterator2>, "Iterators must be copy constructible.");
+ __three_way_comp_ref_type<_Cmp> __wrapped_comp_ref(__comp);
+ if constexpr (__has_random_access_iterator_category<_InputIterator1>::value &&
+ __has_random_access_iterator_category<_InputIterator2>::value) {
+ return std::__lexicographical_compare_three_way_fast_path(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __wrapped_comp_ref);
+ } else {
+ // Unoptimized implementation which compares the iterators against the end in every loop iteration
+ return std::__lexicographical_compare_three_way_slow_path(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __wrapped_comp_ref);
+ }
+}
+
+template <class _InputIterator1, class _InputIterator2>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto lexicographical_compare_three_way(
+ _InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2) {
+ return std::lexicographical_compare_three_way(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), std::compare_three_way());
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_THREE_WAY_H
diff --git a/libcxx/include/__cxx03/__algorithm/lower_bound.h b/libcxx/include/__cxx03/__algorithm/lower_bound.h
new file mode 100644
index 00000000000000..c417d84835497d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/lower_bound.h
@@ -0,0 +1,109 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_LOWER_BOUND_H
+#define _LIBCPP___ALGORITHM_LOWER_BOUND_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/half_positive.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/advance.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_callable.h>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Iter, class _Type, class _Proj, class _Comp>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter __lower_bound_bisecting(
+ _Iter __first,
+ const _Type& __value,
+ typename iterator_traits<_Iter>::difference_type __len,
+ _Comp& __comp,
+ _Proj& __proj) {
+ while (__len != 0) {
+ auto __l2 = std::__half_positive(__len);
+ _Iter __m = __first;
+ _IterOps<_AlgPolicy>::advance(__m, __l2);
+ if (std::__invoke(__comp, std::__invoke(__proj, *__m), __value)) {
+ __first = ++__m;
+ __len -= __l2 + 1;
+ } else {
+ __len = __l2;
+ }
+ }
+ return __first;
+}
+
+// One-sided binary search, aka meta binary search, has been in the public domain for decades, and has the general
+// advantage of being \Omega(1) rather than the classic algorithm's \Omega(log(n)), with the downside of executing at
+// most 2*log(n) comparisons vs the classic algorithm's exact log(n). There are two scenarios in which it really shines:
+// the first one is when operating over non-random-access iterators, because the classic algorithm requires knowing the
+// container's size upfront, which adds \Omega(n) iterator increments to the complexity. The second one is when you're
+// traversing the container in order, trying to fast-forward to the next value: in that case, the classic algorithm
+// would yield \Omega(n*log(n)) comparisons and, for non-random-access iterators, \Omega(n^2) iterator increments,
+// whereas the one-sided version will yield O(n) operations on both counts, with a \Omega(log(n)) bound on the number of
+// comparisons.
+template <class _AlgPolicy, class _ForwardIterator, class _Sent, class _Type, class _Proj, class _Comp>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+__lower_bound_onesided(_ForwardIterator __first, _Sent __last, const _Type& __value, _Comp& __comp, _Proj& __proj) {
+ // step = 0, ensuring we can always short-circuit when distance is 1 later on
+ if (__first == __last || !std::__invoke(__comp, std::__invoke(__proj, *__first), __value))
+ return __first;
+
+ using _Distance = typename iterator_traits<_ForwardIterator>::difference_type;
+ for (_Distance __step = 1; __first != __last; __step <<= 1) {
+ auto __it = __first;
+ auto __dist = __step - _IterOps<_AlgPolicy>::__advance_to(__it, __step, __last);
+ // once we reach the last range where needle can be we must start
+ // looking inwards, bisecting that range
+ if (__it == __last || !std::__invoke(__comp, std::__invoke(__proj, *__it), __value)) {
+ // we've already checked the previous value and it was less, we can save
+ // one comparison by skipping bisection
+ if (__dist == 1)
+ return __it;
+ return std::__lower_bound_bisecting<_AlgPolicy>(__first, __value, __dist, __comp, __proj);
+ }
+ // range not found, move forward!
+ __first = __it;
+ }
+ return __first;
+}
+
+template <class _AlgPolicy, class _ForwardIterator, class _Sent, class _Type, class _Proj, class _Comp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+__lower_bound(_ForwardIterator __first, _Sent __last, const _Type& __value, _Comp& __comp, _Proj& __proj) {
+ const auto __dist = _IterOps<_AlgPolicy>::distance(__first, __last);
+ return std::__lower_bound_bisecting<_AlgPolicy>(__first, __value, __dist, __comp, __proj);
+}
+
+template <class _ForwardIterator, class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, _Compare __comp) {
+ static_assert(__is_callable<_Compare, decltype(*__first), const _Tp&>::value, "The comparator has to be callable");
+ auto __proj = std::__identity();
+ return std::__lower_bound<_ClassicAlgPolicy>(__first, __last, __value, __comp, __proj);
+}
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ return std::lower_bound(__first, __last, __value, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_LOWER_BOUND_H
diff --git a/libcxx/include/__cxx03/__algorithm/make_heap.h b/libcxx/include/__cxx03/__algorithm/make_heap.h
new file mode 100644
index 00000000000000..e8f0cdb27333a4
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/make_heap.h
@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MAKE_HEAP_H
+#define _LIBCPP___ALGORITHM_MAKE_HEAP_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/sift_down.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare&& __comp) {
+ __comp_ref_type<_Compare> __comp_ref = __comp;
+
+ using difference_type = typename iterator_traits<_RandomAccessIterator>::difference_type;
+ difference_type __n = __last - __first;
+ if (__n > 1) {
+ // start from the first parent, there is no need to consider children
+ for (difference_type __start = (__n - 2) / 2; __start >= 0; --__start) {
+ std::__sift_down<_AlgPolicy>(__first, __comp_ref, __n, __first + __start);
+ }
+ }
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ std::__make_heap<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ std::make_heap(std::move(__first), std::move(__last), __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MAKE_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/make_projected.h b/libcxx/include/__cxx03/__algorithm/make_projected.h
new file mode 100644
index 00000000000000..5245e523f3df21
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/make_projected.h
@@ -0,0 +1,106 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MAKE_PROJECTED_H
+#define _LIBCPP___ALGORITHM_MAKE_PROJECTED_H
+
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_member_pointer.h>
+#include <__type_traits/is_same.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Pred, class _Proj>
+struct _ProjectedPred {
+ _Pred& __pred; // Can be a unary or a binary predicate.
+ _Proj& __proj;
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI _ProjectedPred(_Pred& __pred_arg, _Proj& __proj_arg)
+ : __pred(__pred_arg), __proj(__proj_arg) {}
+
+ template <class _Tp>
+ typename __invoke_of<_Pred&, decltype(std::__invoke(std::declval<_Proj&>(), std::declval<_Tp>()))>::type
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI
+ operator()(_Tp&& __v) const {
+ return std::__invoke(__pred, std::__invoke(__proj, std::forward<_Tp>(__v)));
+ }
+
+ template <class _T1, class _T2>
+ typename __invoke_of<_Pred&,
+ decltype(std::__invoke(std::declval<_Proj&>(), std::declval<_T1>())),
+ decltype(std::__invoke(std::declval<_Proj&>(), std::declval<_T2>()))>::type _LIBCPP_CONSTEXPR
+ _LIBCPP_HIDE_FROM_ABI
+ operator()(_T1&& __lhs, _T2&& __rhs) const {
+ return std::__invoke(
+ __pred, std::__invoke(__proj, std::forward<_T1>(__lhs)), std::__invoke(__proj, std::forward<_T2>(__rhs)));
+ }
+};
+
+template <
+ class _Pred,
+ class _Proj,
+ __enable_if_t<!(!is_member_pointer<__decay_t<_Pred> >::value && __is_identity<__decay_t<_Proj> >::value), int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ProjectedPred<_Pred, _Proj> __make_projected(_Pred& __pred, _Proj& __proj) {
+ return _ProjectedPred<_Pred, _Proj>(__pred, __proj);
+}
+
+// Avoid creating the functor and just use the pristine comparator -- for certain algorithms, this would enable
+// optimizations that rely on the type of the comparator. Additionally, this results in less layers of indirection in
+// the call stack when the comparator is invoked, even in an unoptimized build.
+template <
+ class _Pred,
+ class _Proj,
+ __enable_if_t<!is_member_pointer<__decay_t<_Pred> >::value && __is_identity<__decay_t<_Proj> >::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Pred& __make_projected(_Pred& __pred, _Proj&) {
+ return __pred;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Comp, class _Proj1, class _Proj2>
+_LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) __make_projected_comp(_Comp& __comp, _Proj1& __proj1, _Proj2& __proj2) {
+ if constexpr (__is_identity<decay_t<_Proj1>>::value && __is_identity<decay_t<_Proj2>>::value &&
+ !is_member_pointer_v<decay_t<_Comp>>) {
+ // Avoid creating the lambda and just use the pristine comparator -- for certain algorithms, this would enable
+ // optimizations that rely on the type of the comparator.
+ return __comp;
+
+ } else {
+ return [&](auto&& __lhs, auto&& __rhs) -> bool {
+ return std::invoke(__comp,
+ std::invoke(__proj1, std::forward<decltype(__lhs)>(__lhs)),
+ std::invoke(__proj2, std::forward<decltype(__rhs)>(__rhs)));
+ };
+ }
+}
+
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___ALGORITHM_MAKE_PROJECTED_H
diff --git a/libcxx/include/__cxx03/__algorithm/max.h b/libcxx/include/__cxx03/__algorithm/max.h
new file mode 100644
index 00000000000000..d4c99f6f364367
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/max.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MAX_H
+#define _LIBCPP___ALGORITHM_MAX_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/max_element.h>
+#include <__config>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&
+max(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b, _Compare __comp) {
+ return __comp(__a, __b) ? __b : __a;
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&
+max(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b) {
+ return std::max(__a, __b, __less<>());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp
+max(initializer_list<_Tp> __t, _Compare __comp) {
+ return *std::__max_element<__comp_ref_type<_Compare> >(__t.begin(), __t.end(), __comp);
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp max(initializer_list<_Tp> __t) {
+ return *std::max_element(__t.begin(), __t.end(), __less<>());
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MAX_H
diff --git a/libcxx/include/__cxx03/__algorithm/max_element.h b/libcxx/include/__cxx03/__algorithm/max_element.h
new file mode 100644
index 00000000000000..c036726cbccd8b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/max_element.h
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MAX_ELEMENT_H
+#define _LIBCPP___ALGORITHM_MAX_ELEMENT_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Compare, class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
+__max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
+ static_assert(
+ __has_forward_iterator_category<_ForwardIterator>::value, "std::max_element requires a ForwardIterator");
+ if (__first != __last) {
+ _ForwardIterator __i = __first;
+ while (++__i != __last)
+ if (__comp(*__first, *__i))
+ __first = __i;
+ }
+ return __first;
+}
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
+max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
+ return std::__max_element<__comp_ref_type<_Compare> >(__first, __last, __comp);
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
+max_element(_ForwardIterator __first, _ForwardIterator __last) {
+ return std::max_element(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_MAX_ELEMENT_H
diff --git a/libcxx/include/__cxx03/__algorithm/merge.h b/libcxx/include/__cxx03/__algorithm/merge.h
new file mode 100644
index 00000000000000..bad663c4b9f102
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/merge.h
@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MERGE_H
+#define _LIBCPP___ALGORITHM_MERGE_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/copy.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator __merge(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result,
+ _Compare __comp) {
+ for (; __first1 != __last1; ++__result) {
+ if (__first2 == __last2)
+ return std::copy(__first1, __last1, __result);
+ if (__comp(*__first2, *__first1)) {
+ *__result = *__first2;
+ ++__first2;
+ } else {
+ *__result = *__first1;
+ ++__first1;
+ }
+ }
+ return std::copy(__first2, __last2, __result);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+merge(_InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result,
+ _Compare __comp) {
+ return std::__merge<__comp_ref_type<_Compare> >(__first1, __last1, __first2, __last2, __result, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+merge(_InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result) {
+ return std::merge(__first1, __last1, __first2, __last2, __result, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_MERGE_H
diff --git a/libcxx/include/__cxx03/__algorithm/min.h b/libcxx/include/__cxx03/__algorithm/min.h
new file mode 100644
index 00000000000000..1bafad8a461eb9
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/min.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MIN_H
+#define _LIBCPP___ALGORITHM_MIN_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/min_element.h>
+#include <__config>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&
+min(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b, _Compare __comp) {
+ return __comp(__b, __a) ? __b : __a;
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&
+min(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b) {
+ return std::min(__a, __b, __less<>());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp
+min(initializer_list<_Tp> __t, _Compare __comp) {
+ return *std::__min_element<__comp_ref_type<_Compare> >(__t.begin(), __t.end(), __comp);
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp min(initializer_list<_Tp> __t) {
+ return *std::min_element(__t.begin(), __t.end(), __less<>());
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MIN_H
diff --git a/libcxx/include/__cxx03/__algorithm/min_element.h b/libcxx/include/__cxx03/__algorithm/min_element.h
new file mode 100644
index 00000000000000..65f3594d630cef
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/min_element.h
@@ -0,0 +1,71 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MIN_ELEMENT_H
+#define _LIBCPP___ALGORITHM_MIN_ELEMENT_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_callable.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Comp, class _Iter, class _Sent, class _Proj>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Iter
+__min_element(_Iter __first, _Sent __last, _Comp __comp, _Proj& __proj) {
+ if (__first == __last)
+ return __first;
+
+ _Iter __i = __first;
+ while (++__i != __last)
+ if (std::__invoke(__comp, std::__invoke(__proj, *__i), std::__invoke(__proj, *__first)))
+ __first = __i;
+
+ return __first;
+}
+
+template <class _Comp, class _Iter, class _Sent>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Iter __min_element(_Iter __first, _Sent __last, _Comp __comp) {
+ auto __proj = __identity();
+ return std::__min_element<_Comp>(std::move(__first), std::move(__last), __comp, __proj);
+}
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
+min_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
+ static_assert(
+ __has_forward_iterator_category<_ForwardIterator>::value, "std::min_element requires a ForwardIterator");
+ static_assert(
+ __is_callable<_Compare, decltype(*__first), decltype(*__first)>::value, "The comparator has to be callable");
+
+ return std::__min_element<__comp_ref_type<_Compare> >(std::move(__first), std::move(__last), __comp);
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
+min_element(_ForwardIterator __first, _ForwardIterator __last) {
+ return std::min_element(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MIN_ELEMENT_H
diff --git a/libcxx/include/__cxx03/__algorithm/min_max_result.h b/libcxx/include/__cxx03/__algorithm/min_max_result.h
new file mode 100644
index 00000000000000..e988df7c114ee5
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/min_max_result.h
@@ -0,0 +1,56 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MIN_MAX_RESULT_H
+#define _LIBCPP___ALGORITHM_MIN_MAX_RESULT_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _T1>
+struct min_max_result {
+ _LIBCPP_NO_UNIQUE_ADDRESS _T1 min;
+ _LIBCPP_NO_UNIQUE_ADDRESS _T1 max;
+
+ template <class _T2>
+ requires convertible_to<const _T1&, _T2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator min_max_result<_T2>() const& {
+ return {min, max};
+ }
+
+ template <class _T2>
+ requires convertible_to<_T1, _T2>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator min_max_result<_T2>() && {
+ return {std::move(min), std::move(max)};
+ }
+};
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MIN_MAX_RESULT_H
diff --git a/libcxx/include/__cxx03/__algorithm/minmax.h b/libcxx/include/__cxx03/__algorithm/minmax.h
new file mode 100644
index 00000000000000..9feda2b4c0da90
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/minmax.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MINMAX_H
+#define _LIBCPP___ALGORITHM_MINMAX_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/minmax_element.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__type_traits/is_callable.h>
+#include <__utility/pair.h>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<const _Tp&, const _Tp&>
+minmax(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b, _Compare __comp) {
+ return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a) : pair<const _Tp&, const _Tp&>(__a, __b);
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<const _Tp&, const _Tp&>
+minmax(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b) {
+ return std::minmax(__a, __b, __less<>());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Tp, _Tp>
+minmax(initializer_list<_Tp> __t, _Compare __comp) {
+ static_assert(__is_callable<_Compare, _Tp, _Tp>::value, "The comparator has to be callable");
+ __identity __proj;
+ auto __ret = std::__minmax_element_impl(__t.begin(), __t.end(), __comp, __proj);
+ return pair<_Tp, _Tp>(*__ret.first, *__ret.second);
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Tp, _Tp>
+minmax(initializer_list<_Tp> __t) {
+ return std::minmax(__t, __less<>());
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_MINMAX_H
diff --git a/libcxx/include/__cxx03/__algorithm/minmax_element.h b/libcxx/include/__cxx03/__algorithm/minmax_element.h
new file mode 100644
index 00000000000000..43cb23347c3465
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/minmax_element.h
@@ -0,0 +1,100 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MINMAX_ELEMENT_H
+#define _LIBCPP___ALGORITHM_MINMAX_ELEMENT_H
+
+#include <__algorithm/comp.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_callable.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Comp, class _Proj>
+class _MinmaxElementLessFunc {
+ _Comp& __comp_;
+ _Proj& __proj_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _MinmaxElementLessFunc(_Comp& __comp, _Proj& __proj)
+ : __comp_(__comp), __proj_(__proj) {}
+
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(_Iter& __it1, _Iter& __it2) {
+ return std::__invoke(__comp_, std::__invoke(__proj_, *__it1), std::__invoke(__proj_, *__it2));
+ }
+};
+
+template <class _Iter, class _Sent, class _Proj, class _Comp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter, _Iter>
+__minmax_element_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __less = _MinmaxElementLessFunc<_Comp, _Proj>(__comp, __proj);
+
+ pair<_Iter, _Iter> __result(__first, __first);
+ if (__first == __last || ++__first == __last)
+ return __result;
+
+ if (__less(__first, __result.first))
+ __result.first = __first;
+ else
+ __result.second = __first;
+
+ while (++__first != __last) {
+ _Iter __i = __first;
+ if (++__first == __last) {
+ if (__less(__i, __result.first))
+ __result.first = __i;
+ else if (!__less(__i, __result.second))
+ __result.second = __i;
+ return __result;
+ }
+
+ if (__less(__first, __i)) {
+ if (__less(__first, __result.first))
+ __result.first = __first;
+ if (!__less(__i, __result.second))
+ __result.second = __i;
+ } else {
+ if (__less(__i, __result.first))
+ __result.first = __i;
+ if (!__less(__first, __result.second))
+ __result.second = __first;
+ }
+ }
+
+ return __result;
+}
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_ForwardIterator, _ForwardIterator>
+minmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
+ static_assert(
+ __has_forward_iterator_category<_ForwardIterator>::value, "std::minmax_element requires a ForwardIterator");
+ static_assert(
+ __is_callable<_Compare, decltype(*__first), decltype(*__first)>::value, "The comparator has to be callable");
+ auto __proj = __identity();
+ return std::__minmax_element_impl(__first, __last, __comp, __proj);
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_ForwardIterator, _ForwardIterator>
+minmax_element(_ForwardIterator __first, _ForwardIterator __last) {
+ return std::minmax_element(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_MINMAX_ELEMENT_H
diff --git a/libcxx/include/__cxx03/__algorithm/mismatch.h b/libcxx/include/__cxx03/__algorithm/mismatch.h
new file mode 100644
index 00000000000000..632bec02406a41
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/mismatch.h
@@ -0,0 +1,217 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MISMATCH_H
+#define _LIBCPP___ALGORITHM_MISMATCH_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/min.h>
+#include <__algorithm/simd_utils.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__iterator/aliasing_iterator.h>
+#include <__type_traits/desugars_to.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_equality_comparable.h>
+#include <__type_traits/is_integral.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/unreachable.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Iter1, class _Sent1, class _Iter2, class _Pred, class _Proj1, class _Proj2>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Iter1, _Iter2>
+__mismatch_loop(_Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ while (__first1 != __last1) {
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ break;
+ ++__first1;
+ ++__first2;
+ }
+ return std::make_pair(std::move(__first1), std::move(__first2));
+}
+
+template <class _Iter1, class _Sent1, class _Iter2, class _Pred, class _Proj1, class _Proj2>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Iter1, _Iter2>
+__mismatch(_Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ return std::__mismatch_loop(__first1, __last1, __first2, __pred, __proj1, __proj2);
+}
+
+#if _LIBCPP_VECTORIZE_ALGORITHMS
+
+template <class _Iter>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Iter, _Iter>
+__mismatch_vectorized(_Iter __first1, _Iter __last1, _Iter __first2) {
+ using __value_type = __iter_value_type<_Iter>;
+ constexpr size_t __unroll_count = 4;
+ constexpr size_t __vec_size = __native_vector_size<__value_type>;
+ using __vec = __simd_vector<__value_type, __vec_size>;
+
+ if (!__libcpp_is_constant_evaluated()) {
+ auto __orig_first1 = __first1;
+ auto __last2 = __first2 + (__last1 - __first1);
+ while (static_cast<size_t>(__last1 - __first1) >= __unroll_count * __vec_size) [[__unlikely__]] {
+ __vec __lhs[__unroll_count];
+ __vec __rhs[__unroll_count];
+
+ for (size_t __i = 0; __i != __unroll_count; ++__i) {
+ __lhs[__i] = std::__load_vector<__vec>(__first1 + __i * __vec_size);
+ __rhs[__i] = std::__load_vector<__vec>(__first2 + __i * __vec_size);
+ }
+
+ for (size_t __i = 0; __i != __unroll_count; ++__i) {
+ if (auto __cmp_res = __lhs[__i] == __rhs[__i]; !std::__all_of(__cmp_res)) {
+ auto __offset = __i * __vec_size + std::__find_first_not_set(__cmp_res);
+ return {__first1 + __offset, __first2 + __offset};
+ }
+ }
+
+ __first1 += __unroll_count * __vec_size;
+ __first2 += __unroll_count * __vec_size;
+ }
+
+ // check the remaining 0-3 vectors
+ while (static_cast<size_t>(__last1 - __first1) >= __vec_size) {
+ if (auto __cmp_res = std::__load_vector<__vec>(__first1) == std::__load_vector<__vec>(__first2);
+ !std::__all_of(__cmp_res)) {
+ auto __offset = std::__find_first_not_set(__cmp_res);
+ return {__first1 + __offset, __first2 + __offset};
+ }
+ __first1 += __vec_size;
+ __first2 += __vec_size;
+ }
+
+ if (__last1 - __first1 == 0)
+ return {__first1, __first2};
+
+ // Check if we can load elements in front of the current pointer. If that's the case load a vector at
+ // (last - vector_size) to check the remaining elements
+ if (static_cast<size_t>(__first1 - __orig_first1) >= __vec_size) {
+ __first1 = __last1 - __vec_size;
+ __first2 = __last2 - __vec_size;
+ auto __offset =
+ std::__find_first_not_set(std::__load_vector<__vec>(__first1) == std::__load_vector<__vec>(__first2));
+ return {__first1 + __offset, __first2 + __offset};
+ } // else loop over the elements individually
+ }
+
+ __equal_to __pred;
+ __identity __proj;
+ return std::__mismatch_loop(__first1, __last1, __first2, __pred, __proj, __proj);
+}
+
+template <class _Tp,
+ class _Pred,
+ class _Proj1,
+ class _Proj2,
+ __enable_if_t<is_integral<_Tp>::value && __desugars_to_v<__equal_tag, _Pred, _Tp, _Tp> &&
+ __is_identity<_Proj1>::value && __is_identity<_Proj2>::value,
+ int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Tp*, _Tp*>
+__mismatch(_Tp* __first1, _Tp* __last1, _Tp* __first2, _Pred&, _Proj1&, _Proj2&) {
+ return std::__mismatch_vectorized(__first1, __last1, __first2);
+}
+
+template <class _Tp,
+ class _Pred,
+ class _Proj1,
+ class _Proj2,
+ __enable_if_t<!is_integral<_Tp>::value && __desugars_to_v<__equal_tag, _Pred, _Tp, _Tp> &&
+ __is_identity<_Proj1>::value && __is_identity<_Proj2>::value &&
+ __can_map_to_integer_v<_Tp> && __libcpp_is_trivially_equality_comparable<_Tp, _Tp>::value,
+ int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Tp*, _Tp*>
+__mismatch(_Tp* __first1, _Tp* __last1, _Tp* __first2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ if (__libcpp_is_constant_evaluated()) {
+ return std::__mismatch_loop(__first1, __last1, __first2, __pred, __proj1, __proj2);
+ } else {
+ using _Iter = __aliasing_iterator<_Tp*, __get_as_integer_type_t<_Tp>>;
+ auto __ret = std::__mismatch_vectorized(_Iter(__first1), _Iter(__last1), _Iter(__first2));
+ return {__ret.first.__base(), __ret.second.__base()};
+ }
+}
+#endif // _LIBCPP_VECTORIZE_ALGORITHMS
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred) {
+ __identity __proj;
+ auto __res = std::__mismatch(
+ std::__unwrap_iter(__first1), std::__unwrap_iter(__last1), std::__unwrap_iter(__first2), __pred, __proj, __proj);
+ return std::make_pair(std::__rewrap_iter(__first1, __res.first), std::__rewrap_iter(__first2, __res.second));
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2) {
+ return std::mismatch(__first1, __last1, __first2, __equal_to());
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Iter1, _Iter2> __mismatch(
+ _Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Sent2 __last2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ while (__first1 != __last1 && __first2 != __last2) {
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ break;
+ ++__first1;
+ ++__first2;
+ }
+ return {std::move(__first1), std::move(__first2)};
+}
+
+template <class _Tp, class _Pred, class _Proj1, class _Proj2>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Tp*, _Tp*>
+__mismatch(_Tp* __first1, _Tp* __last1, _Tp* __first2, _Tp* __last2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ auto __len = std::min(__last1 - __first1, __last2 - __first2);
+ return std::__mismatch(__first1, __first1 + __len, __first2, __pred, __proj1, __proj2);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _BinaryPredicate __pred) {
+ __identity __proj;
+ auto __res = std::__mismatch(
+ std::__unwrap_iter(__first1),
+ std::__unwrap_iter(__last1),
+ std::__unwrap_iter(__first2),
+ std::__unwrap_iter(__last2),
+ __pred,
+ __proj,
+ __proj);
+ return {std::__rewrap_iter(__first1, __res.first), std::__rewrap_iter(__first2, __res.second)};
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2) {
+ return std::mismatch(__first1, __last1, __first2, __last2, __equal_to());
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MISMATCH_H
diff --git a/libcxx/include/__cxx03/__algorithm/move.h b/libcxx/include/__cxx03/__algorithm/move.h
new file mode 100644
index 00000000000000..1716d43e2a613d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/move.h
@@ -0,0 +1,127 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MOVE_H
+#define _LIBCPP___ALGORITHM_MOVE_H
+
+#include <__algorithm/copy_move_common.h>
+#include <__algorithm/for_each_segment.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min.h>
+#include <__config>
+#include <__iterator/segmented_iterator.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _InIter, class _Sent, class _OutIter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+__move(_InIter __first, _Sent __last, _OutIter __result);
+
+template <class _AlgPolicy>
+struct __move_impl {
+ template <class _InIter, class _Sent, class _OutIter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+ while (__first != __last) {
+ *__result = _IterOps<_AlgPolicy>::__iter_move(__first);
+ ++__first;
+ ++__result;
+ }
+ return std::make_pair(std::move(__first), std::move(__result));
+ }
+
+ template <class _InIter, class _OutIter>
+ struct _MoveSegment {
+ using _Traits = __segmented_iterator_traits<_InIter>;
+
+ _OutIter& __result_;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit _MoveSegment(_OutIter& __result)
+ : __result_(__result) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+ operator()(typename _Traits::__local_iterator __lfirst, typename _Traits::__local_iterator __llast) {
+ __result_ = std::__move<_AlgPolicy>(__lfirst, __llast, std::move(__result_)).second;
+ }
+ };
+
+ template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+ std::__for_each_segment(__first, __last, _MoveSegment<_InIter, _OutIter>(__result));
+ return std::make_pair(__last, std::move(__result));
+ }
+
+ template <class _InIter,
+ class _OutIter,
+ __enable_if_t<__has_random_access_iterator_category<_InIter>::value &&
+ !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+ using _Traits = __segmented_iterator_traits<_OutIter>;
+ using _DiffT = typename common_type<__iter_diff_t<_InIter>, __iter_diff_t<_OutIter> >::type;
+
+ if (__first == __last)
+ return std::make_pair(std::move(__first), std::move(__result));
+
+ auto __local_first = _Traits::__local(__result);
+ auto __segment_iterator = _Traits::__segment(__result);
+ while (true) {
+ auto __local_last = _Traits::__end(__segment_iterator);
+ auto __size = std::min<_DiffT>(__local_last - __local_first, __last - __first);
+ auto __iters = std::__move<_AlgPolicy>(__first, __first + __size, __local_first);
+ __first = std::move(__iters.first);
+
+ if (__first == __last)
+ return std::make_pair(std::move(__first), _Traits::__compose(__segment_iterator, std::move(__iters.second)));
+
+ __local_first = _Traits::__begin(++__segment_iterator);
+ }
+ }
+
+ // At this point, the iterators have been unwrapped so any `contiguous_iterator` has been unwrapped to a pointer.
+ template <class _In, class _Out, __enable_if_t<__can_lower_move_assignment_to_memmove<_In, _Out>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
+ operator()(_In* __first, _In* __last, _Out* __result) const {
+ return std::__copy_trivial_impl(__first, __last, __result);
+ }
+};
+
+template <class _AlgPolicy, class _InIter, class _Sent, class _OutIter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+__move(_InIter __first, _Sent __last, _OutIter __result) {
+ return std::__copy_move_unwrap_iters<__move_impl<_AlgPolicy> >(
+ std::move(__first), std::move(__last), std::move(__result));
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+move(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
+ static_assert(is_copy_constructible<_InputIterator>::value, "Iterators has to be copy constructible.");
+ static_assert(is_copy_constructible<_OutputIterator>::value, "The output iterator has to be copy constructible.");
+
+ return std::__move<_ClassicAlgPolicy>(std::move(__first), std::move(__last), std::move(__result)).second;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MOVE_H
diff --git a/libcxx/include/__cxx03/__algorithm/move_backward.h b/libcxx/include/__cxx03/__algorithm/move_backward.h
new file mode 100644
index 00000000000000..4beb7bdbaac0d0
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/move_backward.h
@@ -0,0 +1,137 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_MOVE_BACKWARD_H
+#define _LIBCPP___ALGORITHM_MOVE_BACKWARD_H
+
+#include <__algorithm/copy_move_common.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min.h>
+#include <__config>
+#include <__iterator/segmented_iterator.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _BidirectionalIterator1, class _Sentinel, class _BidirectionalIterator2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_BidirectionalIterator1, _BidirectionalIterator2>
+__move_backward(_BidirectionalIterator1 __first, _Sentinel __last, _BidirectionalIterator2 __result);
+
+template <class _AlgPolicy>
+struct __move_backward_impl {
+ template <class _InIter, class _Sent, class _OutIter>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+ auto __last_iter = _IterOps<_AlgPolicy>::next(__first, __last);
+ auto __original_last_iter = __last_iter;
+
+ while (__first != __last_iter) {
+ *--__result = _IterOps<_AlgPolicy>::__iter_move(--__last_iter);
+ }
+
+ return std::make_pair(std::move(__original_last_iter), std::move(__result));
+ }
+
+ template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+ using _Traits = __segmented_iterator_traits<_InIter>;
+ auto __sfirst = _Traits::__segment(__first);
+ auto __slast = _Traits::__segment(__last);
+ if (__sfirst == __slast) {
+ auto __iters =
+ std::__move_backward<_AlgPolicy>(_Traits::__local(__first), _Traits::__local(__last), std::move(__result));
+ return std::make_pair(__last, __iters.second);
+ }
+
+ __result =
+ std::__move_backward<_AlgPolicy>(_Traits::__begin(__slast), _Traits::__local(__last), std::move(__result))
+ .second;
+ --__slast;
+ while (__sfirst != __slast) {
+ __result =
+ std::__move_backward<_AlgPolicy>(_Traits::__begin(__slast), _Traits::__end(__slast), std::move(__result))
+ .second;
+ --__slast;
+ }
+ __result = std::__move_backward<_AlgPolicy>(_Traits::__local(__first), _Traits::__end(__slast), std::move(__result))
+ .second;
+ return std::make_pair(__last, std::move(__result));
+ }
+
+ template <class _InIter,
+ class _OutIter,
+ __enable_if_t<__has_random_access_iterator_category<_InIter>::value &&
+ !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+ using _Traits = __segmented_iterator_traits<_OutIter>;
+ using _DiffT = typename common_type<__iter_diff_t<_InIter>, __iter_diff_t<_OutIter> >::type;
+
+ // When the range contains no elements, __result might not be a valid iterator
+ if (__first == __last)
+ return std::make_pair(__first, __result);
+
+ auto __orig_last = __last;
+
+ auto __local_last = _Traits::__local(__result);
+ auto __segment_iterator = _Traits::__segment(__result);
+ while (true) {
+ auto __local_first = _Traits::__begin(__segment_iterator);
+ auto __size = std::min<_DiffT>(__local_last - __local_first, __last - __first);
+ auto __iter = std::__move_backward<_AlgPolicy>(__last - __size, __last, __local_last).second;
+ __last -= __size;
+
+ if (__first == __last)
+ return std::make_pair(std::move(__orig_last), _Traits::__compose(__segment_iterator, std::move(__iter)));
+
+ __local_last = _Traits::__end(--__segment_iterator);
+ }
+ }
+
+ // At this point, the iterators have been unwrapped so any `contiguous_iterator` has been unwrapped to a pointer.
+ template <class _In, class _Out, __enable_if_t<__can_lower_move_assignment_to_memmove<_In, _Out>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
+ operator()(_In* __first, _In* __last, _Out* __result) const {
+ return std::__copy_backward_trivial_impl(__first, __last, __result);
+ }
+};
+
+template <class _AlgPolicy, class _BidirectionalIterator1, class _Sentinel, class _BidirectionalIterator2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_BidirectionalIterator1, _BidirectionalIterator2>
+__move_backward(_BidirectionalIterator1 __first, _Sentinel __last, _BidirectionalIterator2 __result) {
+ static_assert(std::is_copy_constructible<_BidirectionalIterator1>::value &&
+ std::is_copy_constructible<_BidirectionalIterator1>::value,
+ "Iterators must be copy constructible.");
+
+ return std::__copy_move_unwrap_iters<__move_backward_impl<_AlgPolicy> >(
+ std::move(__first), std::move(__last), std::move(__result));
+}
+
+template <class _BidirectionalIterator1, class _BidirectionalIterator2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _BidirectionalIterator2
+move_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last, _BidirectionalIterator2 __result) {
+ return std::__move_backward<_ClassicAlgPolicy>(std::move(__first), std::move(__last), std::move(__result)).second;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MOVE_BACKWARD_H
diff --git a/libcxx/include/__cxx03/__algorithm/next_permutation.h b/libcxx/include/__cxx03/__algorithm/next_permutation.h
new file mode 100644
index 00000000000000..011ee028cc2f52
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/next_permutation.h
@@ -0,0 +1,75 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_NEXT_PERMUTATION_H
+#define _LIBCPP___ALGORITHM_NEXT_PERMUTATION_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/reverse.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _BidirectionalIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_BidirectionalIterator, bool>
+__next_permutation(_BidirectionalIterator __first, _Sentinel __last, _Compare&& __comp) {
+ using _Result = pair<_BidirectionalIterator, bool>;
+
+ _BidirectionalIterator __last_iter = _IterOps<_AlgPolicy>::next(__first, __last);
+ _BidirectionalIterator __i = __last_iter;
+ if (__first == __last || __first == --__i)
+ return _Result(std::move(__last_iter), false);
+
+ while (true) {
+ _BidirectionalIterator __ip1 = __i;
+ if (__comp(*--__i, *__ip1)) {
+ _BidirectionalIterator __j = __last_iter;
+ while (!__comp(*__i, *--__j))
+ ;
+ _IterOps<_AlgPolicy>::iter_swap(__i, __j);
+ std::__reverse<_AlgPolicy>(__ip1, __last_iter);
+ return _Result(std::move(__last_iter), true);
+ }
+ if (__i == __first) {
+ std::__reverse<_AlgPolicy>(__first, __last_iter);
+ return _Result(std::move(__last_iter), false);
+ }
+ }
+}
+
+template <class _BidirectionalIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp) {
+ return std::__next_permutation<_ClassicAlgPolicy>(
+ std::move(__first), std::move(__last), static_cast<__comp_ref_type<_Compare> >(__comp))
+ .second;
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last) {
+ return std::next_permutation(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_NEXT_PERMUTATION_H
diff --git a/libcxx/include/__cxx03/__algorithm/none_of.h b/libcxx/include/__cxx03/__algorithm/none_of.h
new file mode 100644
index 00000000000000..50841ba17cc63e
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/none_of.h
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_NONE_OF_H
+#define _LIBCPP___ALGORITHM_NONE_OF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+none_of(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ return false;
+ return true;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_NONE_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/nth_element.h b/libcxx/include/__cxx03/__algorithm/nth_element.h
new file mode 100644
index 00000000000000..da748d7255aba6
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/nth_element.h
@@ -0,0 +1,261 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_NTH_ELEMENT_H
+#define _LIBCPP___ALGORITHM_NTH_ELEMENT_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/sort.h>
+#include <__assert>
+#include <__config>
+#include <__debug_utils/randomize_range.h>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Compare, class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool __nth_element_find_guard(
+ _RandomAccessIterator& __i, _RandomAccessIterator& __j, _RandomAccessIterator __m, _Compare __comp) {
+ // manually guard downward moving __j against __i
+ while (true) {
+ if (__i == --__j) {
+ return false;
+ }
+ if (__comp(*__j, *__m)) {
+ return true; // found guard for downward moving __j, now use unguarded partition
+ }
+ }
+}
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+// NOLINTNEXTLINE(readability-function-cognitive-complexity)
+__nth_element(
+ _RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ // _Compare is known to be a reference type
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ const difference_type __limit = 7;
+ while (true) {
+ if (__nth == __last)
+ return;
+ difference_type __len = __last - __first;
+ switch (__len) {
+ case 0:
+ case 1:
+ return;
+ case 2:
+ if (__comp(*--__last, *__first))
+ _Ops::iter_swap(__first, __last);
+ return;
+ case 3: {
+ _RandomAccessIterator __m = __first;
+ std::__sort3<_AlgPolicy, _Compare>(__first, ++__m, --__last, __comp);
+ return;
+ }
+ }
+ if (__len <= __limit) {
+ std::__selection_sort<_AlgPolicy, _Compare>(__first, __last, __comp);
+ return;
+ }
+ // __len > __limit >= 3
+ _RandomAccessIterator __m = __first + __len / 2;
+ _RandomAccessIterator __lm1 = __last;
+ unsigned __n_swaps = std::__sort3<_AlgPolicy, _Compare>(__first, __m, --__lm1, __comp);
+ // *__m is median
+ // partition [__first, __m) < *__m and *__m <= [__m, __last)
+ // (this inhibits tossing elements equivalent to __m around unnecessarily)
+ _RandomAccessIterator __i = __first;
+ _RandomAccessIterator __j = __lm1;
+ // j points beyond range to be tested, *__lm1 is known to be <= *__m
+ // The search going up is known to be guarded but the search coming down isn't.
+ // Prime the downward search with a guard.
+ if (!__comp(*__i, *__m)) // if *__first == *__m
+ {
+ // *__first == *__m, *__first doesn't go in first part
+ if (std::__nth_element_find_guard<_Compare>(__i, __j, __m, __comp)) {
+ _Ops::iter_swap(__i, __j);
+ ++__n_swaps;
+ } else {
+ // *__first == *__m, *__m <= all other elements
+ // Partition instead into [__first, __i) == *__first and *__first < [__i, __last)
+ ++__i; // __first + 1
+ __j = __last;
+ if (!__comp(*__first, *--__j)) { // we need a guard if *__first == *(__last-1)
+ while (true) {
+ if (__i == __j) {
+ return; // [__first, __last) all equivalent elements
+ } else if (__comp(*__first, *__i)) {
+ _Ops::iter_swap(__i, __j);
+ ++__n_swaps;
+ ++__i;
+ break;
+ }
+ ++__i;
+ }
+ }
+ // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
+ if (__i == __j) {
+ return;
+ }
+ while (true) {
+ while (!__comp(*__first, *__i)) {
+ ++__i;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __i != __last,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ }
+ do {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __j != __first,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ --__j;
+ } while (__comp(*__first, *__j));
+ if (__i >= __j)
+ break;
+ _Ops::iter_swap(__i, __j);
+ ++__n_swaps;
+ ++__i;
+ }
+ // [__first, __i) == *__first and *__first < [__i, __last)
+ // The first part is sorted,
+ if (__nth < __i) {
+ return;
+ }
+ // __nth_element the second part
+ // std::__nth_element<_Compare>(__i, __nth, __last, __comp);
+ __first = __i;
+ continue;
+ }
+ }
+ ++__i;
+ // j points beyond range to be tested, *__lm1 is known to be <= *__m
+ // if not yet partitioned...
+ if (__i < __j) {
+ // known that *(__i - 1) < *__m
+ while (true) {
+ // __m still guards upward moving __i
+ while (__comp(*__i, *__m)) {
+ ++__i;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __i != __last,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ }
+ // It is now known that a guard exists for downward moving __j
+ do {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __j != __first,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ --__j;
+ } while (!__comp(*__j, *__m));
+ if (__i >= __j)
+ break;
+ _Ops::iter_swap(__i, __j);
+ ++__n_swaps;
+ // It is known that __m != __j
+ // If __m just moved, follow it
+ if (__m == __i)
+ __m = __j;
+ ++__i;
+ }
+ }
+ // [__first, __i) < *__m and *__m <= [__i, __last)
+ if (__i != __m && __comp(*__m, *__i)) {
+ _Ops::iter_swap(__i, __m);
+ ++__n_swaps;
+ }
+ // [__first, __i) < *__i and *__i <= [__i+1, __last)
+ if (__nth == __i)
+ return;
+ if (__n_swaps == 0) {
+ // We were given a perfectly partitioned sequence. Coincidence?
+ if (__nth < __i) {
+ // Check for [__first, __i) already sorted
+ __j = __m = __first;
+ while (true) {
+ if (++__j == __i) {
+ // [__first, __i) sorted
+ return;
+ }
+ if (__comp(*__j, *__m)) {
+ // not yet sorted, so sort
+ break;
+ }
+ __m = __j;
+ }
+ } else {
+ // Check for [__i, __last) already sorted
+ __j = __m = __i;
+ while (true) {
+ if (++__j == __last) {
+ // [__i, __last) sorted
+ return;
+ }
+ if (__comp(*__j, *__m)) {
+ // not yet sorted, so sort
+ break;
+ }
+ __m = __j;
+ }
+ }
+ }
+ // __nth_element on range containing __nth
+ if (__nth < __i) {
+ // std::__nth_element<_Compare>(__first, __nth, __i, __comp);
+ __last = __i;
+ } else {
+ // std::__nth_element<_Compare>(__i+1, __nth, __last, __comp);
+ __first = ++__i;
+ }
+ }
+}
+
+template <class _AlgPolicy, class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __nth_element_impl(
+ _RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare& __comp) {
+ if (__nth == __last)
+ return;
+
+ std::__debug_randomize_range<_AlgPolicy>(__first, __last);
+
+ std::__nth_element<_AlgPolicy, __comp_ref_type<_Compare> >(__first, __nth, __last, __comp);
+
+ std::__debug_randomize_range<_AlgPolicy>(__first, __nth);
+ if (__nth != __last) {
+ std::__debug_randomize_range<_AlgPolicy>(++__nth, __last);
+ }
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp) {
+ std::__nth_element_impl<_ClassicAlgPolicy>(std::move(__first), std::move(__nth), std::move(__last), __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last) {
+ std::nth_element(std::move(__first), std::move(__nth), std::move(__last), __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_NTH_ELEMENT_H
diff --git a/libcxx/include/__cxx03/__algorithm/partial_sort.h b/libcxx/include/__cxx03/__algorithm/partial_sort.h
new file mode 100644
index 00000000000000..7f8d0c49147e3a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/partial_sort.h
@@ -0,0 +1,91 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PARTIAL_SORT_H
+#define _LIBCPP___ALGORITHM_PARTIAL_SORT_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_heap.h>
+#include <__algorithm/sift_down.h>
+#include <__algorithm/sort_heap.h>
+#include <__config>
+#include <__debug_utils/randomize_range.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _RandomAccessIterator __partial_sort_impl(
+ _RandomAccessIterator __first, _RandomAccessIterator __middle, _Sentinel __last, _Compare&& __comp) {
+ if (__first == __middle) {
+ return _IterOps<_AlgPolicy>::next(__middle, __last);
+ }
+
+ std::__make_heap<_AlgPolicy>(__first, __middle, __comp);
+
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len = __middle - __first;
+ _RandomAccessIterator __i = __middle;
+ for (; __i != __last; ++__i) {
+ if (__comp(*__i, *__first)) {
+ _IterOps<_AlgPolicy>::iter_swap(__i, __first);
+ std::__sift_down<_AlgPolicy>(__first, __comp, __len, __first);
+ }
+ }
+ std::__sort_heap<_AlgPolicy>(std::move(__first), std::move(__middle), __comp);
+
+ return __i;
+}
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _RandomAccessIterator
+__partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _Sentinel __last, _Compare& __comp) {
+ if (__first == __middle)
+ return _IterOps<_AlgPolicy>::next(__middle, __last);
+
+ std::__debug_randomize_range<_AlgPolicy>(__first, __last);
+
+ auto __last_iter =
+ std::__partial_sort_impl<_AlgPolicy>(__first, __middle, __last, static_cast<__comp_ref_type<_Compare> >(__comp));
+
+ std::__debug_randomize_range<_AlgPolicy>(__middle, __last);
+
+ return __last_iter;
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void partial_sort(
+ _RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last, _Compare __comp) {
+ static_assert(std::is_copy_constructible<_RandomAccessIterator>::value, "Iterators must be copy constructible.");
+ static_assert(std::is_copy_assignable<_RandomAccessIterator>::value, "Iterators must be copy assignable.");
+
+ (void)std::__partial_sort<_ClassicAlgPolicy>(std::move(__first), std::move(__middle), std::move(__last), __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last) {
+ std::partial_sort(__first, __middle, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_PARTIAL_SORT_H
diff --git a/libcxx/include/__cxx03/__algorithm/partial_sort_copy.h b/libcxx/include/__cxx03/__algorithm/partial_sort_copy.h
new file mode 100644
index 00000000000000..ef7c9d34d94983
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/partial_sort_copy.h
@@ -0,0 +1,106 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PARTIAL_SORT_COPY_H
+#define _LIBCPP___ALGORITHM_PARTIAL_SORT_COPY_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_heap.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/sift_down.h>
+#include <__algorithm/sort_heap.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_callable.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy,
+ class _Compare,
+ class _InputIterator,
+ class _Sentinel1,
+ class _RandomAccessIterator,
+ class _Sentinel2,
+ class _Proj1,
+ class _Proj2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_InputIterator, _RandomAccessIterator> __partial_sort_copy(
+ _InputIterator __first,
+ _Sentinel1 __last,
+ _RandomAccessIterator __result_first,
+ _Sentinel2 __result_last,
+ _Compare&& __comp,
+ _Proj1&& __proj1,
+ _Proj2&& __proj2) {
+ _RandomAccessIterator __r = __result_first;
+ auto&& __projected_comp = std::__make_projected(__comp, __proj2);
+
+ if (__r != __result_last) {
+ for (; __first != __last && __r != __result_last; ++__first, (void)++__r)
+ *__r = *__first;
+ std::__make_heap<_AlgPolicy>(__result_first, __r, __projected_comp);
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len = __r - __result_first;
+ for (; __first != __last; ++__first)
+ if (std::__invoke(__comp, std::__invoke(__proj1, *__first), std::__invoke(__proj2, *__result_first))) {
+ *__result_first = *__first;
+ std::__sift_down<_AlgPolicy>(__result_first, __projected_comp, __len, __result_first);
+ }
+ std::__sort_heap<_AlgPolicy>(__result_first, __r, __projected_comp);
+ }
+
+ return pair<_InputIterator, _RandomAccessIterator>(
+ _IterOps<_AlgPolicy>::next(std::move(__first), std::move(__last)), std::move(__r));
+}
+
+template <class _InputIterator, class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _RandomAccessIterator partial_sort_copy(
+ _InputIterator __first,
+ _InputIterator __last,
+ _RandomAccessIterator __result_first,
+ _RandomAccessIterator __result_last,
+ _Compare __comp) {
+ static_assert(
+ __is_callable<_Compare, decltype(*__first), decltype(*__result_first)>::value, "Comparator has to be callable");
+
+ auto __result = std::__partial_sort_copy<_ClassicAlgPolicy>(
+ __first,
+ __last,
+ __result_first,
+ __result_last,
+ static_cast<__comp_ref_type<_Compare> >(__comp),
+ __identity(),
+ __identity());
+ return __result.second;
+}
+
+template <class _InputIterator, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _RandomAccessIterator partial_sort_copy(
+ _InputIterator __first,
+ _InputIterator __last,
+ _RandomAccessIterator __result_first,
+ _RandomAccessIterator __result_last) {
+ return std::partial_sort_copy(__first, __last, __result_first, __result_last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_PARTIAL_SORT_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/partition.h b/libcxx/include/__cxx03/__algorithm/partition.h
new file mode 100644
index 00000000000000..824e49b9ec2149
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/partition.h
@@ -0,0 +1,90 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PARTITION_H
+#define _LIBCPP___ALGORITHM_PARTITION_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Predicate, class _AlgPolicy, class _ForwardIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator, _ForwardIterator>
+__partition_impl(_ForwardIterator __first, _Sentinel __last, _Predicate __pred, forward_iterator_tag) {
+ while (true) {
+ if (__first == __last)
+ return std::make_pair(std::move(__first), std::move(__first));
+ if (!__pred(*__first))
+ break;
+ ++__first;
+ }
+
+ _ForwardIterator __p = __first;
+ while (++__p != __last) {
+ if (__pred(*__p)) {
+ _IterOps<_AlgPolicy>::iter_swap(__first, __p);
+ ++__first;
+ }
+ }
+ return std::make_pair(std::move(__first), std::move(__p));
+}
+
+template <class _Predicate, class _AlgPolicy, class _BidirectionalIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_BidirectionalIterator, _BidirectionalIterator>
+__partition_impl(_BidirectionalIterator __first, _Sentinel __sentinel, _Predicate __pred, bidirectional_iterator_tag) {
+ _BidirectionalIterator __original_last = _IterOps<_AlgPolicy>::next(__first, __sentinel);
+ _BidirectionalIterator __last = __original_last;
+
+ while (true) {
+ while (true) {
+ if (__first == __last)
+ return std::make_pair(std::move(__first), std::move(__original_last));
+ if (!__pred(*__first))
+ break;
+ ++__first;
+ }
+ do {
+ if (__first == --__last)
+ return std::make_pair(std::move(__first), std::move(__original_last));
+ } while (!__pred(*__last));
+ _IterOps<_AlgPolicy>::iter_swap(__first, __last);
+ ++__first;
+ }
+}
+
+template <class _AlgPolicy, class _ForwardIterator, class _Sentinel, class _Predicate, class _IterCategory>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator, _ForwardIterator>
+__partition(_ForwardIterator __first, _Sentinel __last, _Predicate&& __pred, _IterCategory __iter_category) {
+ return std::__partition_impl<__remove_cvref_t<_Predicate>&, _AlgPolicy>(
+ std::move(__first), std::move(__last), __pred, __iter_category);
+}
+
+template <class _ForwardIterator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ using _IterCategory = typename iterator_traits<_ForwardIterator>::iterator_category;
+ auto __result = std::__partition<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __pred, _IterCategory());
+ return __result.first;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_PARTITION_H
diff --git a/libcxx/include/__cxx03/__algorithm/partition_copy.h b/libcxx/include/__cxx03/__algorithm/partition_copy.h
new file mode 100644
index 00000000000000..147b45c7882a51
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/partition_copy.h
@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PARTITION_COPY_H
+#define _LIBCPP___ALGORITHM_PARTITION_COPY_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator1, class _OutputIterator2, class _Predicate>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_OutputIterator1, _OutputIterator2> partition_copy(
+ _InputIterator __first,
+ _InputIterator __last,
+ _OutputIterator1 __out_true,
+ _OutputIterator2 __out_false,
+ _Predicate __pred) {
+ for (; __first != __last; ++__first) {
+ if (__pred(*__first)) {
+ *__out_true = *__first;
+ ++__out_true;
+ } else {
+ *__out_false = *__first;
+ ++__out_false;
+ }
+ }
+ return pair<_OutputIterator1, _OutputIterator2>(__out_true, __out_false);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_PARTITION_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/partition_point.h b/libcxx/include/__cxx03/__algorithm/partition_point.h
new file mode 100644
index 00000000000000..504dbf1d1a0556
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/partition_point.h
@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PARTITION_POINT_H
+#define _LIBCPP___ALGORITHM_PARTITION_POINT_H
+
+#include <__algorithm/half_positive.h>
+#include <__config>
+#include <__iterator/advance.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Predicate>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+partition_point(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
+ difference_type __len = std::distance(__first, __last);
+ while (__len != 0) {
+ difference_type __l2 = std::__half_positive(__len);
+ _ForwardIterator __m = __first;
+ std::advance(__m, __l2);
+ if (__pred(*__m)) {
+ __first = ++__m;
+ __len -= __l2 + 1;
+ } else
+ __len = __l2;
+ }
+ return __first;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_PARTITION_POINT_H
diff --git a/libcxx/include/__cxx03/__algorithm/pop_heap.h b/libcxx/include/__cxx03/__algorithm/pop_heap.h
new file mode 100644
index 00000000000000..6d23830097ff96
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/pop_heap.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_POP_HEAP_H
+#define _LIBCPP___ALGORITHM_POP_HEAP_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/push_heap.h>
+#include <__algorithm/sift_down.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__pop_heap(_RandomAccessIterator __first,
+ _RandomAccessIterator __last,
+ _Compare& __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len) {
+ // Calling `pop_heap` on an empty range is undefined behavior, but in practice it will be a no-op.
+ _LIBCPP_ASSERT_PEDANTIC(__len > 0, "The heap given to pop_heap must be non-empty");
+
+ __comp_ref_type<_Compare> __comp_ref = __comp;
+
+ using value_type = typename iterator_traits<_RandomAccessIterator>::value_type;
+ if (__len > 1) {
+ value_type __top = _IterOps<_AlgPolicy>::__iter_move(__first); // create a hole at __first
+ _RandomAccessIterator __hole = std::__floyd_sift_down<_AlgPolicy>(__first, __comp_ref, __len);
+ --__last;
+
+ if (__hole == __last) {
+ *__hole = std::move(__top);
+ } else {
+ *__hole = _IterOps<_AlgPolicy>::__iter_move(__last);
+ ++__hole;
+ *__last = std::move(__top);
+ std::__sift_up<_AlgPolicy>(__first, __hole, __comp_ref, __hole - __first);
+ }
+ }
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ static_assert(std::is_copy_constructible<_RandomAccessIterator>::value, "Iterators must be copy constructible.");
+ static_assert(std::is_copy_assignable<_RandomAccessIterator>::value, "Iterators must be copy assignable.");
+
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len = __last - __first;
+ std::__pop_heap<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp, __len);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ std::pop_heap(std::move(__first), std::move(__last), __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_POP_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/prev_permutation.h b/libcxx/include/__cxx03/__algorithm/prev_permutation.h
new file mode 100644
index 00000000000000..8d15b6806401d8
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/prev_permutation.h
@@ -0,0 +1,75 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PREV_PERMUTATION_H
+#define _LIBCPP___ALGORITHM_PREV_PERMUTATION_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/reverse.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _BidirectionalIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_BidirectionalIterator, bool>
+__prev_permutation(_BidirectionalIterator __first, _Sentinel __last, _Compare&& __comp) {
+ using _Result = pair<_BidirectionalIterator, bool>;
+
+ _BidirectionalIterator __last_iter = _IterOps<_AlgPolicy>::next(__first, __last);
+ _BidirectionalIterator __i = __last_iter;
+ if (__first == __last || __first == --__i)
+ return _Result(std::move(__last_iter), false);
+
+ while (true) {
+ _BidirectionalIterator __ip1 = __i;
+ if (__comp(*__ip1, *--__i)) {
+ _BidirectionalIterator __j = __last_iter;
+ while (!__comp(*--__j, *__i))
+ ;
+ _IterOps<_AlgPolicy>::iter_swap(__i, __j);
+ std::__reverse<_AlgPolicy>(__ip1, __last_iter);
+ return _Result(std::move(__last_iter), true);
+ }
+ if (__i == __first) {
+ std::__reverse<_AlgPolicy>(__first, __last_iter);
+ return _Result(std::move(__last_iter), false);
+ }
+ }
+}
+
+template <class _BidirectionalIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp) {
+ return std::__prev_permutation<_ClassicAlgPolicy>(
+ std::move(__first), std::move(__last), static_cast<__comp_ref_type<_Compare> >(__comp))
+ .second;
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last) {
+ return std::prev_permutation(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_PREV_PERMUTATION_H
diff --git a/libcxx/include/__cxx03/__algorithm/pstl.h b/libcxx/include/__cxx03/__algorithm/pstl.h
new file mode 100644
index 00000000000000..0bb052b3f97c76
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/pstl.h
@@ -0,0 +1,663 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_H
+#define _LIBCPP___ALGORITHM_PSTL_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+# include <__functional/operations.h>
+# include <__iterator/cpp17_iterator_concepts.h>
+# include <__iterator/iterator_traits.h>
+# include <__pstl/backend.h>
+# include <__pstl/dispatch.h>
+# include <__pstl/handle_exception.h>
+# include <__type_traits/enable_if.h>
+# include <__type_traits/is_execution_policy.h>
+# include <__type_traits/remove_cvref.h>
+# include <__utility/forward.h>
+# include <__utility/move.h>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Predicate,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool
+any_of(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "any_of requires a ForwardIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__any_of, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Pred,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool
+all_of(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Pred __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "all_of requires a ForwardIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__all_of, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Pred,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool
+none_of(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Pred __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "none_of requires a ForwardIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__none_of, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _ForwardOutIterator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator
+copy(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _ForwardOutIterator __result) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(
+ _ForwardIterator, "copy(first, last, result) requires [first, last) to be ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(
+ _ForwardOutIterator, "copy(first, last, result) requires result to be a ForwardIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(
+ _ForwardOutIterator, decltype(*__first), "copy(first, last, result) requires result to be an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__copy, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__result));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _ForwardOutIterator,
+ class _Size,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator
+copy_n(_ExecutionPolicy&& __policy, _ForwardIterator __first, _Size __n, _ForwardOutIterator __result) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(
+ _ForwardIterator, "copy_n(first, n, result) requires first to be a ForwardIterator");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(
+ _ForwardOutIterator, "copy_n(first, n, result) requires result to be a ForwardIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(
+ _ForwardOutIterator, decltype(*__first), "copy_n(first, n, result) requires result to be an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__copy_n, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__n), std::move(__result));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Predicate,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI __iter_diff_t<_ForwardIterator>
+count_if(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(
+ _ForwardIterator, "count_if(first, last, pred) requires [first, last) to be ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__count_if, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI __iter_diff_t<_ForwardIterator>
+count(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(
+ _ForwardIterator, "count(first, last, val) requires [first, last) to be ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__count, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), __value);
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _Pred,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI bool
+equal(_ExecutionPolicy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _Pred __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "equal requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "equal requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__equal_3leg, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI bool
+equal(_ExecutionPolicy&& __policy, _ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "equal requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "equal requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__equal_3leg, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ equal_to{});
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _Pred,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI bool
+equal(_ExecutionPolicy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _Pred __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "equal requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "equal requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__equal, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI bool
+equal(_ExecutionPolicy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "equal requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "equal requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__equal, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ equal_to{});
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+fill(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "fill requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__fill, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), __value);
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Size,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+fill_n(_ExecutionPolicy&& __policy, _ForwardIterator __first, _Size __n, const _Tp& __value) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "fill_n requires a ForwardIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__fill_n, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__n), __value);
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Predicate,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator
+find_if(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "find_if requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__find_if, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Predicate,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator
+find_if_not(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "find_if_not requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__find_if_not, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator
+find(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "find requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__find, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), __value);
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Function,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+for_each(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Function __func) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "for_each requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__for_each, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__func));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Size,
+ class _Function,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+for_each_n(_ExecutionPolicy&& __policy, _ForwardIterator __first, _Size __size, _Function __func) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "for_each_n requires a ForwardIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__for_each_n, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__size), std::move(__func));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Generator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+generate(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Generator __gen) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "generate requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__generate, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__gen));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Size,
+ class _Generator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+generate_n(_ExecutionPolicy&& __policy, _ForwardIterator __first, _Size __n, _Generator __gen) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "generate_n requires a ForwardIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__generate_n, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__n), std::move(__gen));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Predicate,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool
+is_partitioned(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "is_partitioned requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__is_partitioned, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__pred));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _ForwardOutIterator,
+ class _Comp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator
+merge(_ExecutionPolicy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _ForwardOutIterator __result,
+ _Comp __comp) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "merge requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "merge requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(_ForwardOutIterator, decltype(*__first1), "merge requires an OutputIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(_ForwardOutIterator, decltype(*__first2), "merge requires an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__merge, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ std::move(__comp));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _ForwardOutIterator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator
+merge(_ExecutionPolicy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _ForwardOutIterator __result) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "merge requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "merge requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(_ForwardOutIterator, decltype(*__first1), "merge requires an OutputIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(_ForwardOutIterator, decltype(*__first2), "merge requires an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__merge, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ less{});
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _ForwardOutIterator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator
+move(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _ForwardOutIterator __result) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "move requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardOutIterator, "move requires an OutputIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(
+ _ForwardOutIterator, decltype(std::move(*__first)), "move requires an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__move, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__result));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Pred,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+replace_if(_ExecutionPolicy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _Pred __pred,
+ const _Tp& __new_value) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "replace_if requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__replace_if, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__pred), __new_value);
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+replace(_ExecutionPolicy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ const _Tp& __old_value,
+ const _Tp& __new_value) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "replace requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__replace, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), __old_value, __new_value);
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _ForwardOutIterator,
+ class _Pred,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void replace_copy_if(
+ _ExecutionPolicy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _ForwardOutIterator __result,
+ _Pred __pred,
+ const _Tp& __new_value) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "replace_copy_if requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardOutIterator, "replace_copy_if requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(
+ _ForwardOutIterator, decltype(*__first), "replace_copy_if requires an OutputIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(_ForwardOutIterator, const _Tp&, "replace_copy requires an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__replace_copy_if, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first),
+ std::move(__last),
+ std::move(__result),
+ std::move(__pred),
+ __new_value);
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _ForwardOutIterator,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void replace_copy(
+ _ExecutionPolicy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _ForwardOutIterator __result,
+ const _Tp& __old_value,
+ const _Tp& __new_value) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "replace_copy requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardOutIterator, "replace_copy requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(
+ _ForwardOutIterator, decltype(*__first), "replace_copy requires an OutputIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(_ForwardOutIterator, const _Tp&, "replace_copy requires an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__replace_copy, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first),
+ std::move(__last),
+ std::move(__result),
+ __old_value,
+ __new_value);
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _ForwardOutIterator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator rotate_copy(
+ _ExecutionPolicy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __middle,
+ _ForwardIterator __last,
+ _ForwardOutIterator __result) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "rotate_copy requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardOutIterator, "rotate_copy requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(
+ _ForwardOutIterator, decltype(*__first), "rotate_copy requires an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__rotate_copy, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first),
+ std::move(__middle),
+ std::move(__last),
+ std::move(__result));
+}
+
+template <class _ExecutionPolicy,
+ class _RandomAccessIterator,
+ class _Comp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+sort(_ExecutionPolicy&& __policy, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
+ _LIBCPP_REQUIRE_CPP17_RANDOM_ACCESS_ITERATOR(_RandomAccessIterator, "sort requires RandomAccessIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__sort, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__comp));
+}
+
+template <class _ExecutionPolicy,
+ class _RandomAccessIterator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+sort(_ExecutionPolicy&& __policy, _RandomAccessIterator __first, _RandomAccessIterator __last) {
+ _LIBCPP_REQUIRE_CPP17_RANDOM_ACCESS_ITERATOR(_RandomAccessIterator, "sort requires RandomAccessIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__sort, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), less{});
+}
+
+template <class _ExecutionPolicy,
+ class _RandomAccessIterator,
+ class _Comp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+stable_sort(_ExecutionPolicy&& __policy, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
+ _LIBCPP_REQUIRE_CPP17_RANDOM_ACCESS_ITERATOR(_RandomAccessIterator, "stable_sort requires RandomAccessIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__stable_sort, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__comp));
+}
+
+template <class _ExecutionPolicy,
+ class _RandomAccessIterator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void
+stable_sort(_ExecutionPolicy&& __policy, _RandomAccessIterator __first, _RandomAccessIterator __last) {
+ _LIBCPP_REQUIRE_CPP17_RANDOM_ACCESS_ITERATOR(_RandomAccessIterator, "stable_sort requires RandomAccessIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__stable_sort, __pstl::__current_configuration, _RawPolicy>;
+ __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), less{});
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _ForwardOutIterator,
+ class _UnaryOperation,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator transform(
+ _ExecutionPolicy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _ForwardOutIterator __result,
+ _UnaryOperation __op) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "transform requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardOutIterator, "transform requires an OutputIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(
+ _ForwardOutIterator, decltype(__op(*__first)), "transform requires an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__transform, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first),
+ std::move(__last),
+ std::move(__result),
+ std::move(__op));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _ForwardOutIterator,
+ class _BinaryOperation,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator transform(
+ _ExecutionPolicy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardOutIterator __result,
+ _BinaryOperation __op) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "transform requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "transform requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardOutIterator, "transform requires an OutputIterator");
+ _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(
+ _ForwardOutIterator, decltype(__op(*__first1, *__first2)), "transform requires an OutputIterator");
+ using _Implementation = __pstl::__dispatch<__pstl::__transform_binary, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__result),
+ std::move(__op));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_PSTL_H
diff --git a/libcxx/include/__cxx03/__algorithm/push_heap.h b/libcxx/include/__cxx03/__algorithm/push_heap.h
new file mode 100644
index 00000000000000..ec0b445f2b70f3
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/push_heap.h
@@ -0,0 +1,84 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PUSH_HEAP_H
+#define _LIBCPP___ALGORITHM_PUSH_HEAP_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__sift_up(_RandomAccessIterator __first,
+ _RandomAccessIterator __last,
+ _Compare&& __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len) {
+ using value_type = typename iterator_traits<_RandomAccessIterator>::value_type;
+
+ if (__len > 1) {
+ __len = (__len - 2) / 2;
+ _RandomAccessIterator __ptr = __first + __len;
+
+ if (__comp(*__ptr, *--__last)) {
+ value_type __t(_IterOps<_AlgPolicy>::__iter_move(__last));
+ do {
+ *__last = _IterOps<_AlgPolicy>::__iter_move(__ptr);
+ __last = __ptr;
+ if (__len == 0)
+ break;
+ __len = (__len - 1) / 2;
+ __ptr = __first + __len;
+ } while (__comp(*__ptr, __t));
+
+ *__last = std::move(__t);
+ }
+ }
+}
+
+template <class _AlgPolicy, class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare& __comp) {
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len = __last - __first;
+ std::__sift_up<_AlgPolicy, __comp_ref_type<_Compare> >(std::move(__first), std::move(__last), __comp, __len);
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ static_assert(std::is_copy_constructible<_RandomAccessIterator>::value, "Iterators must be copy constructible.");
+ static_assert(std::is_copy_assignable<_RandomAccessIterator>::value, "Iterators must be copy assignable.");
+
+ std::__push_heap<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ std::push_heap(std::move(__first), std::move(__last), __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_PUSH_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_adjacent_find.h b/libcxx/include/__cxx03/__algorithm/ranges_adjacent_find.h
new file mode 100644
index 00000000000000..3c54f723310a6f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_adjacent_find.h
@@ -0,0 +1,83 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_ADJACENT_FIND_H
+#define _LIBCPP___ALGORITHM_RANGES_ADJACENT_FIND_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __adjacent_find {
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __adjacent_find_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {
+ if (__first == __last)
+ return __first;
+
+ auto __i = __first;
+ while (++__i != __last) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first), std::invoke(__proj, *__i)))
+ return __first;
+ __first = __i;
+ }
+ return __i;
+ }
+
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_binary_predicate<projected<_Iter, _Proj>, projected<_Iter, _Proj>> _Pred = ranges::equal_to>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Pred __pred = {}, _Proj __proj = {}) const {
+ return __adjacent_find_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_binary_predicate<projected<iterator_t<_Range>, _Proj>, projected<iterator_t<_Range>, _Proj>>
+ _Pred = ranges::equal_to>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __range, _Pred __pred = {}, _Proj __proj = {}) const {
+ return __adjacent_find_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+} // namespace __adjacent_find
+
+inline namespace __cpo {
+inline constexpr auto adjacent_find = __adjacent_find::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_ADJACENT_FIND_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_all_of.h b/libcxx/include/__cxx03/__algorithm/ranges_all_of.h
new file mode 100644
index 00000000000000..2f603b32f32d08
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_all_of.h
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_ALL_OF_H
+#define _LIBCPP___ALGORITHM_RANGES_ALL_OF_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __all_of {
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr static bool __all_of_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (!std::invoke(__pred, std::invoke(__proj, *__first)))
+ return false;
+ }
+ return true;
+ }
+
+ template <input_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) const {
+ return __all_of_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <input_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
+ return __all_of_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+} // namespace __all_of
+
+inline namespace __cpo {
+inline constexpr auto all_of = __all_of::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_ALL_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_any_of.h b/libcxx/include/__cxx03/__algorithm/ranges_any_of.h
new file mode 100644
index 00000000000000..205fcecc086e7a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_any_of.h
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_ANY_OF_H
+#define _LIBCPP___ALGORITHM_RANGES_ANY_OF_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __any_of {
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr static bool __any_of_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first)))
+ return true;
+ }
+ return false;
+ }
+
+ template <input_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Iter __first, _Sent __last, _Pred __pred = {}, _Proj __proj = {}) const {
+ return __any_of_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <input_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
+ return __any_of_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+} // namespace __any_of
+
+inline namespace __cpo {
+inline constexpr auto any_of = __any_of::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_ANY_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_binary_search.h b/libcxx/include/__cxx03/__algorithm/ranges_binary_search.h
new file mode 100644
index 00000000000000..1ef2bd62b5995a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_binary_search.h
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_BINARY_SEARCH_H
+#define _LIBCPP___ALGORITHM_RANGES_BINARY_SEARCH_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/lower_bound.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __binary_search {
+struct __fn {
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<const _Type*, projected<_Iter, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Iter __first, _Sent __last, const _Type& __value, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret = std::__lower_bound<_RangeAlgPolicy>(__first, __last, __value, __comp, __proj);
+ return __ret != __last && !std::invoke(__comp, __value, std::invoke(__proj, *__ret));
+ }
+
+ template <forward_range _Range,
+ class _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<const _Type*, projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Range&& __r, const _Type& __value, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __first = ranges::begin(__r);
+ auto __last = ranges::end(__r);
+ auto __ret = std::__lower_bound<_RangeAlgPolicy>(__first, __last, __value, __comp, __proj);
+ return __ret != __last && !std::invoke(__comp, __value, std::invoke(__proj, *__ret));
+ }
+};
+} // namespace __binary_search
+
+inline namespace __cpo {
+inline constexpr auto binary_search = __binary_search::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_BINARY_SEARCH_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_clamp.h b/libcxx/include/__cxx03/__algorithm/ranges_clamp.h
new file mode 100644
index 00000000000000..e6181ef9435e09
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_clamp.h
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_CLAMP_H
+#define _LIBCPP___ALGORITHM_RANGES_CLAMP_H
+
+#include <__assert>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __clamp {
+struct __fn {
+ template <class _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Type*, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr const _Type& operator()(
+ const _Type& __value, const _Type& __low, const _Type& __high, _Comp __comp = {}, _Proj __proj = {}) const {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ !bool(std::invoke(__comp, std::invoke(__proj, __high), std::invoke(__proj, __low))),
+ "Bad bounds passed to std::ranges::clamp");
+
+ auto&& __projected = std::invoke(__proj, __value);
+ if (std::invoke(__comp, std::forward<decltype(__projected)>(__projected), std::invoke(__proj, __low)))
+ return __low;
+ else if (std::invoke(__comp, std::invoke(__proj, __high), std::forward<decltype(__projected)>(__projected)))
+ return __high;
+ else
+ return __value;
+ }
+};
+} // namespace __clamp
+
+inline namespace __cpo {
+inline constexpr auto clamp = __clamp::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_CLAMP_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_contains.h b/libcxx/include/__cxx03/__algorithm/ranges_contains.h
new file mode 100644
index 00000000000000..4836c3baed173e
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_contains.h
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_CONTAINS_H
+#define _LIBCPP___ALGORITHM_RANGES_CONTAINS_H
+
+#include <__algorithm/ranges_find.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__functional/reference_wrapper.h>
+#include <__iterator/concepts.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __contains {
+struct __fn {
+ template <input_iterator _Iter, sentinel_for<_Iter> _Sent, class _Type, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<_Iter, _Proj>, const _Type*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool static
+ operator()(_Iter __first, _Sent __last, const _Type& __value, _Proj __proj = {}) {
+ return ranges::find(std::move(__first), __last, __value, std::ref(__proj)) != __last;
+ }
+
+ template <input_range _Range, class _Type, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _Type*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool static
+ operator()(_Range&& __range, const _Type& __value, _Proj __proj = {}) {
+ return ranges::find(ranges::begin(__range), ranges::end(__range), __value, std::ref(__proj)) !=
+ ranges::end(__range);
+ }
+};
+} // namespace __contains
+
+inline namespace __cpo {
+inline constexpr auto contains = __contains::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_CONTAINS_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_contains_subrange.h b/libcxx/include/__cxx03/__algorithm/ranges_contains_subrange.h
new file mode 100644
index 00000000000000..4398c457fd054d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_contains_subrange.h
@@ -0,0 +1,97 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_CONTAINS_SUBRANGE_H
+#define _LIBCPP___ALGORITHM_RANGES_CONTAINS_SUBRANGE_H
+
+#include <__algorithm/ranges_search.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__functional/reference_wrapper.h>
+#include <__iterator/concepts.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/size.h>
+#include <__ranges/subrange.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __contains_subrange {
+struct __fn {
+ template <forward_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ forward_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool static operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) {
+ if (__first2 == __last2)
+ return true;
+
+ auto __ret = ranges::search(
+ std::move(__first1), __last1, std::move(__first2), __last2, __pred, std::ref(__proj1), std::ref(__proj2));
+ return __ret.empty() == false;
+ }
+
+ template <forward_range _Range1,
+ forward_range _Range2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool static
+ operator()(_Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) {
+ if constexpr (sized_range<_Range2>) {
+ if (ranges::size(__range2) == 0)
+ return true;
+ } else {
+ if (ranges::begin(__range2) == ranges::end(__range2))
+ return true;
+ }
+
+ auto __ret = ranges::search(__range1, __range2, __pred, std::ref(__proj1), std::ref(__proj2));
+ return __ret.empty() == false;
+ }
+};
+} // namespace __contains_subrange
+
+inline namespace __cpo {
+inline constexpr auto contains_subrange = __contains_subrange::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_CONTAINS_SUBRANGE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_copy.h b/libcxx/include/__cxx03/__algorithm/ranges_copy.h
new file mode 100644
index 00000000000000..e1d6d32f05f7e6
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_copy.h
@@ -0,0 +1,71 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_COPY_H
+#define _LIBCPP___ALGORITHM_RANGES_COPY_H
+
+#include <__algorithm/copy.h>
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__iterator/concepts.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using copy_result = in_out_result<_InIter, _OutIter>;
+
+namespace __copy {
+struct __fn {
+ template <input_iterator _InIter, sentinel_for<_InIter> _Sent, weakly_incrementable _OutIter>
+ requires indirectly_copyable<_InIter, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr copy_result<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+ auto __ret = std::__copy<_RangeAlgPolicy>(std::move(__first), std::move(__last), std::move(__result));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <input_range _Range, weakly_incrementable _OutIter>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr copy_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __r, _OutIter __result) const {
+ auto __ret = std::__copy<_RangeAlgPolicy>(ranges::begin(__r), ranges::end(__r), std::move(__result));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+};
+} // namespace __copy
+
+inline namespace __cpo {
+inline constexpr auto copy = __copy::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_copy_backward.h b/libcxx/include/__cxx03/__algorithm/ranges_copy_backward.h
new file mode 100644
index 00000000000000..93e326042503fd
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_copy_backward.h
@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_COPY_BACKWARD_H
+#define _LIBCPP___ALGORITHM_RANGES_COPY_BACKWARD_H
+
+#include <__algorithm/copy_backward.h>
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Ip, class _Op>
+using copy_backward_result = in_out_result<_Ip, _Op>;
+
+namespace __copy_backward {
+struct __fn {
+ template <bidirectional_iterator _InIter1, sentinel_for<_InIter1> _Sent1, bidirectional_iterator _InIter2>
+ requires indirectly_copyable<_InIter1, _InIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr copy_backward_result<_InIter1, _InIter2>
+ operator()(_InIter1 __first, _Sent1 __last, _InIter2 __result) const {
+ auto __ret = std::__copy_backward<_RangeAlgPolicy>(std::move(__first), std::move(__last), std::move(__result));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <bidirectional_range _Range, bidirectional_iterator _Iter>
+ requires indirectly_copyable<iterator_t<_Range>, _Iter>
+ _LIBCPP_HIDE_FROM_ABI constexpr copy_backward_result<borrowed_iterator_t<_Range>, _Iter>
+ operator()(_Range&& __r, _Iter __result) const {
+ auto __ret = std::__copy_backward<_RangeAlgPolicy>(ranges::begin(__r), ranges::end(__r), std::move(__result));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+};
+} // namespace __copy_backward
+
+inline namespace __cpo {
+inline constexpr auto copy_backward = __copy_backward::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_COPY_BACKWARD_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_copy_if.h b/libcxx/include/__cxx03/__algorithm/ranges_copy_if.h
new file mode 100644
index 00000000000000..4b41d2154e7f83
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_copy_if.h
@@ -0,0 +1,87 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_COPY_IF_H
+#define _LIBCPP___ALGORITHM_RANGES_COPY_IF_H
+
+#include <__algorithm/in_out_result.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Ip, class _Op>
+using copy_if_result = in_out_result<_Ip, _Op>;
+
+namespace __copy_if {
+struct __fn {
+ template <class _InIter, class _Sent, class _OutIter, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI static constexpr copy_if_result<_InIter, _OutIter>
+ __copy_if_impl(_InIter __first, _Sent __last, _OutIter __result, _Pred& __pred, _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first))) {
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return {std::move(__first), std::move(__result)};
+ }
+
+ template <input_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ weakly_incrementable _OutIter,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ requires indirectly_copyable<_Iter, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr copy_if_result<_Iter, _OutIter>
+ operator()(_Iter __first, _Sent __last, _OutIter __result, _Pred __pred, _Proj __proj = {}) const {
+ return __copy_if_impl(std::move(__first), std::move(__last), std::move(__result), __pred, __proj);
+ }
+
+ template <input_range _Range,
+ weakly_incrementable _OutIter,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr copy_if_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __r, _OutIter __result, _Pred __pred, _Proj __proj = {}) const {
+ return __copy_if_impl(ranges::begin(__r), ranges::end(__r), std::move(__result), __pred, __proj);
+ }
+};
+} // namespace __copy_if
+
+inline namespace __cpo {
+inline constexpr auto copy_if = __copy_if::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_COPY_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_copy_n.h b/libcxx/include/__cxx03/__algorithm/ranges_copy_n.h
new file mode 100644
index 00000000000000..4353fa99278c8b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_copy_n.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_COPY_N_H
+#define _LIBCPP___ALGORITHM_RANGES_COPY_N_H
+
+#include <__algorithm/copy.h>
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/ranges_copy.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/unreachable_sentinel.h>
+#include <__iterator/wrap_iter.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _Ip, class _Op>
+using copy_n_result = in_out_result<_Ip, _Op>;
+
+namespace __copy_n {
+struct __fn {
+ template <class _InIter, class _DiffType, class _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr static copy_n_result<_InIter, _OutIter>
+ __go(_InIter __first, _DiffType __n, _OutIter __result) {
+ while (__n != 0) {
+ *__result = *__first;
+ ++__first;
+ ++__result;
+ --__n;
+ }
+ return {std::move(__first), std::move(__result)};
+ }
+
+ template <random_access_iterator _InIter, class _DiffType, random_access_iterator _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr static copy_n_result<_InIter, _OutIter>
+ __go(_InIter __first, _DiffType __n, _OutIter __result) {
+ auto __ret = std::__copy<_RangeAlgPolicy>(__first, __first + __n, __result);
+ return {__ret.first, __ret.second};
+ }
+
+ template <input_iterator _Ip, weakly_incrementable _Op>
+ requires indirectly_copyable<_Ip, _Op>
+ _LIBCPP_HIDE_FROM_ABI constexpr copy_n_result<_Ip, _Op>
+ operator()(_Ip __first, iter_difference_t<_Ip> __n, _Op __result) const {
+ return __go(std::move(__first), __n, std::move(__result));
+ }
+};
+} // namespace __copy_n
+
+inline namespace __cpo {
+inline constexpr auto copy_n = __copy_n::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_COPY_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_count.h b/libcxx/include/__cxx03/__algorithm/ranges_count.h
new file mode 100644
index 00000000000000..4f35117438705d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_count.h
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_COUNT_H
+#define _LIBCPP___ALGORITHM_RANGES_COUNT_H
+
+#include <__algorithm/count.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __count {
+struct __fn {
+ template <input_iterator _Iter, sentinel_for<_Iter> _Sent, class _Type, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<_Iter, _Proj>, const _Type*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter>
+ operator()(_Iter __first, _Sent __last, const _Type& __value, _Proj __proj = {}) const {
+ return std::__count<_RangeAlgPolicy>(std::move(__first), std::move(__last), __value, __proj);
+ }
+
+ template <input_range _Range, class _Type, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _Type*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr range_difference_t<_Range>
+ operator()(_Range&& __r, const _Type& __value, _Proj __proj = {}) const {
+ return std::__count<_RangeAlgPolicy>(ranges::begin(__r), ranges::end(__r), __value, __proj);
+ }
+};
+} // namespace __count
+
+inline namespace __cpo {
+inline constexpr auto count = __count::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_COUNT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_count_if.h b/libcxx/include/__cxx03/__algorithm/ranges_count_if.h
new file mode 100644
index 00000000000000..5f2396ff7d5315
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_count_if.h
@@ -0,0 +1,79 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_COUNT_IF_H
+#define _LIBCPP___ALGORITHM_RANGES_COUNT_IF_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+template <class _Iter, class _Sent, class _Proj, class _Pred>
+_LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter>
+__count_if_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {
+ iter_difference_t<_Iter> __counter(0);
+ for (; __first != __last; ++__first) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first)))
+ ++__counter;
+ }
+ return __counter;
+}
+
+namespace __count_if {
+struct __fn {
+ template <input_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Predicate>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter>
+ operator()(_Iter __first, _Sent __last, _Predicate __pred, _Proj __proj = {}) const {
+ return ranges::__count_if_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <input_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Predicate>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr range_difference_t<_Range>
+ operator()(_Range&& __r, _Predicate __pred, _Proj __proj = {}) const {
+ return ranges::__count_if_impl(ranges::begin(__r), ranges::end(__r), __pred, __proj);
+ }
+};
+} // namespace __count_if
+
+inline namespace __cpo {
+inline constexpr auto count_if = __count_if::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_COUNT_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_ends_with.h b/libcxx/include/__cxx03/__algorithm/ranges_ends_with.h
new file mode 100644
index 00000000000000..06efdef36b7cf2
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_ends_with.h
@@ -0,0 +1,201 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_ENDS_WITH_H
+#define _LIBCPP___ALGORITHM_RANGES_ENDS_WITH_H
+
+#include <__algorithm/ranges_equal.h>
+#include <__algorithm/ranges_starts_with.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__functional/reference_wrapper.h>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/reverse_iterator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __ends_with {
+struct __fn {
+ template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __ends_with_fn_impl_bidirectional(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2) {
+ auto __rbegin1 = std::make_reverse_iterator(__last1);
+ auto __rend1 = std::make_reverse_iterator(__first1);
+ auto __rbegin2 = std::make_reverse_iterator(__last2);
+ auto __rend2 = std::make_reverse_iterator(__first2);
+ return ranges::starts_with(
+ __rbegin1, __rend1, __rbegin2, __rend2, std::ref(__pred), std::ref(__proj1), std::ref(__proj2));
+ }
+
+ template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __ends_with_fn_impl(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2) {
+ if constexpr (std::bidirectional_iterator<_Sent1> && std::bidirectional_iterator<_Sent2> &&
+ (!std::random_access_iterator<_Sent1>) && (!std::random_access_iterator<_Sent2>)) {
+ return __ends_with_fn_impl_bidirectional(__first1, __last1, __first2, __last2, __pred, __proj1, __proj2);
+
+ } else {
+ auto __n1 = ranges::distance(__first1, __last1);
+ auto __n2 = ranges::distance(__first2, __last2);
+ if (__n2 == 0)
+ return true;
+ if (__n2 > __n1)
+ return false;
+
+ return __ends_with_fn_impl_with_offset(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ __pred,
+ __proj1,
+ __proj2,
+ __n1 - __n2);
+ }
+ }
+
+ template <class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Pred,
+ class _Proj1,
+ class _Proj2,
+ class _Offset>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __ends_with_fn_impl_with_offset(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2,
+ _Offset __offset) {
+ if constexpr (std::bidirectional_iterator<_Sent1> && std::bidirectional_iterator<_Sent2> &&
+ !std::random_access_iterator<_Sent1> && !std::random_access_iterator<_Sent2>) {
+ return __ends_with_fn_impl_bidirectional(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
+
+ } else {
+ ranges::advance(__first1, __offset);
+ return ranges::equal(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::ref(__pred),
+ std::ref(__proj1),
+ std::ref(__proj2));
+ }
+ }
+
+ template <input_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ input_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires(forward_iterator<_Iter1> || sized_sentinel_for<_Sent1, _Iter1>) &&
+ (forward_iterator<_Iter2> || sized_sentinel_for<_Sent2, _Iter2>) &&
+ indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ return __ends_with_fn_impl(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires(forward_range<_Range1> || sized_range<_Range1>) && (forward_range<_Range2> || sized_range<_Range2>) &&
+ indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ if constexpr (sized_range<_Range1> && sized_range<_Range2>) {
+ auto __n1 = ranges::size(__range1);
+ auto __n2 = ranges::size(__range2);
+ if (__n2 == 0)
+ return true;
+ if (__n2 > __n1)
+ return false;
+ auto __offset = __n1 - __n2;
+
+ return __ends_with_fn_impl_with_offset(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __pred,
+ __proj1,
+ __proj2,
+ __offset);
+
+ } else {
+ return __ends_with_fn_impl(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __pred,
+ __proj1,
+ __proj2);
+ }
+ }
+};
+} // namespace __ends_with
+
+inline namespace __cpo {
+inline constexpr auto ends_with = __ends_with::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_ENDS_WITH_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_equal.h b/libcxx/include/__cxx03/__algorithm/ranges_equal.h
new file mode 100644
index 00000000000000..edbd0e3641c1b8
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_equal.h
@@ -0,0 +1,109 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_EQUAL_H
+#define _LIBCPP___ALGORITHM_RANGES_EQUAL_H
+
+#include <__algorithm/equal.h>
+#include <__algorithm/unwrap_range.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __equal {
+struct __fn {
+ template <input_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ input_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ if constexpr (sized_sentinel_for<_Sent1, _Iter1> && sized_sentinel_for<_Sent2, _Iter2>) {
+ if (__last1 - __first1 != __last2 - __first2)
+ return false;
+ }
+ auto __unwrapped1 = std::__unwrap_range(std::move(__first1), std::move(__last1));
+ auto __unwrapped2 = std::__unwrap_range(std::move(__first2), std::move(__last2));
+ return std::__equal_impl(
+ std::move(__unwrapped1.first),
+ std::move(__unwrapped1.second),
+ std::move(__unwrapped2.first),
+ std::move(__unwrapped2.second),
+ __pred,
+ __proj1,
+ __proj2);
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ if constexpr (sized_range<_Range1> && sized_range<_Range2>) {
+ if (ranges::distance(__range1) != ranges::distance(__range2))
+ return false;
+ }
+ auto __unwrapped1 = std::__unwrap_range(ranges::begin(__range1), ranges::end(__range1));
+ auto __unwrapped2 = std::__unwrap_range(ranges::begin(__range2), ranges::end(__range2));
+ return std::__equal_impl(
+ std::move(__unwrapped1.first),
+ std::move(__unwrapped1.second),
+ std::move(__unwrapped2.first),
+ std::move(__unwrapped2.second),
+ __pred,
+ __proj1,
+ __proj2);
+ return false;
+ }
+};
+} // namespace __equal
+
+inline namespace __cpo {
+inline constexpr auto equal = __equal::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_EQUAL_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_equal_range.h b/libcxx/include/__cxx03/__algorithm/ranges_equal_range.h
new file mode 100644
index 00000000000000..4a308e016b546a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_equal_range.h
@@ -0,0 +1,80 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_EQUAL_RANGE_H
+#define _LIBCPP___ALGORITHM_RANGES_EQUAL_RANGE_H
+
+#include <__algorithm/equal_range.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__ranges/subrange.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __equal_range {
+
+struct __fn {
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Tp,
+ class _Proj = identity,
+ indirect_strict_weak_order<const _Tp*, projected<_Iter, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter>
+ operator()(_Iter __first, _Sent __last, const _Tp& __value, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret = std::__equal_range<_RangeAlgPolicy>(std::move(__first), std::move(__last), __value, __comp, __proj);
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <forward_range _Range,
+ class _Tp,
+ class _Proj = identity,
+ indirect_strict_weak_order<const _Tp*, projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, const _Tp& __value, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret =
+ std::__equal_range<_RangeAlgPolicy>(ranges::begin(__range), ranges::end(__range), __value, __comp, __proj);
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+};
+
+} // namespace __equal_range
+
+inline namespace __cpo {
+inline constexpr auto equal_range = __equal_range::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_EQUAL_RANGE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_fill.h b/libcxx/include/__cxx03/__algorithm/ranges_fill.h
new file mode 100644
index 00000000000000..7a177d85e9f07f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_fill.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FILL_H
+#define _LIBCPP___ALGORITHM_RANGES_FILL_H
+
+#include <__algorithm/ranges_fill_n.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __fill {
+struct __fn {
+ template <class _Type, output_iterator<const _Type&> _Iter, sentinel_for<_Iter> _Sent>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter operator()(_Iter __first, _Sent __last, const _Type& __value) const {
+ if constexpr (random_access_iterator<_Iter> && sized_sentinel_for<_Sent, _Iter>) {
+ return ranges::fill_n(__first, __last - __first, __value);
+ } else {
+ for (; __first != __last; ++__first)
+ *__first = __value;
+ return __first;
+ }
+ }
+
+ template <class _Type, output_range<const _Type&> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range> operator()(_Range&& __range, const _Type& __value) const {
+ return (*this)(ranges::begin(__range), ranges::end(__range), __value);
+ }
+};
+} // namespace __fill
+
+inline namespace __cpo {
+inline constexpr auto fill = __fill::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FILL_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_fill_n.h b/libcxx/include/__cxx03/__algorithm/ranges_fill_n.h
new file mode 100644
index 00000000000000..a6e988c0089ce4
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_fill_n.h
@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FILL_N_H
+#define _LIBCPP___ALGORITHM_RANGES_FILL_N_H
+
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __fill_n {
+struct __fn {
+ template <class _Type, output_iterator<const _Type&> _Iter>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, iter_difference_t<_Iter> __n, const _Type& __value) const {
+ for (; __n != 0; --__n) {
+ *__first = __value;
+ ++__first;
+ }
+ return __first;
+ }
+};
+} // namespace __fill_n
+
+inline namespace __cpo {
+inline constexpr auto fill_n = __fill_n::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FILL_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_find.h b/libcxx/include/__cxx03/__algorithm/ranges_find.h
new file mode 100644
index 00000000000000..6b0d5efe37ab8f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_find.h
@@ -0,0 +1,80 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FIND_H
+#define _LIBCPP___ALGORITHM_RANGES_FIND_H
+
+#include <__algorithm/find.h>
+#include <__algorithm/ranges_find_if.h>
+#include <__algorithm/unwrap_range.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __find {
+struct __fn {
+ template <class _Iter, class _Sent, class _Tp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI static constexpr _Iter
+ __find_unwrap(_Iter __first, _Sent __last, const _Tp& __value, _Proj& __proj) {
+ if constexpr (forward_iterator<_Iter>) {
+ auto [__first_un, __last_un] = std::__unwrap_range(__first, std::move(__last));
+ return std::__rewrap_range<_Sent>(
+ std::move(__first), std::__find(std::move(__first_un), std::move(__last_un), __value, __proj));
+ } else {
+ return std::__find(std::move(__first), std::move(__last), __value, __proj);
+ }
+ }
+
+ template <input_iterator _Ip, sentinel_for<_Ip> _Sp, class _Tp, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<_Ip, _Proj>, const _Tp*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Ip
+ operator()(_Ip __first, _Sp __last, const _Tp& __value, _Proj __proj = {}) const {
+ return __find_unwrap(std::move(__first), std::move(__last), __value, __proj);
+ }
+
+ template <input_range _Rp, class _Tp, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Rp>, _Proj>, const _Tp*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp>
+ operator()(_Rp&& __r, const _Tp& __value, _Proj __proj = {}) const {
+ return __find_unwrap(ranges::begin(__r), ranges::end(__r), __value, __proj);
+ }
+};
+} // namespace __find
+
+inline namespace __cpo {
+inline constexpr auto find = __find::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FIND_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_find_end.h b/libcxx/include/__cxx03/__algorithm/ranges_find_end.h
new file mode 100644
index 00000000000000..e49e66dd4ac04b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_find_end.h
@@ -0,0 +1,103 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FIND_END_H
+#define _LIBCPP___ALGORITHM_RANGES_FIND_END_H
+
+#include <__algorithm/find_end.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/ranges_iterator_concept.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/subrange.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __find_end {
+struct __fn {
+ template <forward_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ forward_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter1> operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__find_end_impl<_RangeAlgPolicy>(
+ __first1,
+ __last1,
+ __first2,
+ __last2,
+ __pred,
+ __proj1,
+ __proj2,
+ __iterator_concept<_Iter1>(),
+ __iterator_concept<_Iter2>());
+ return {__ret.first, __ret.second};
+ }
+
+ template <forward_range _Range1,
+ forward_range _Range2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range1> operator()(
+ _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ auto __ret = std::__find_end_impl<_RangeAlgPolicy>(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __pred,
+ __proj1,
+ __proj2,
+ __iterator_concept<iterator_t<_Range1>>(),
+ __iterator_concept<iterator_t<_Range2>>());
+ return {__ret.first, __ret.second};
+ }
+};
+} // namespace __find_end
+
+inline namespace __cpo {
+inline constexpr auto find_end = __find_end::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FIND_END_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_find_first_of.h b/libcxx/include/__cxx03/__algorithm/ranges_find_first_of.h
new file mode 100644
index 00000000000000..d92d9686bc4420
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_find_first_of.h
@@ -0,0 +1,106 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FIND_FIRST_OF_H
+#define _LIBCPP___ALGORITHM_RANGES_FIND_FIRST_OF_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __find_first_of {
+struct __fn {
+ template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter1 __find_first_of_impl(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2) {
+ for (; __first1 != __last1; ++__first1) {
+ for (auto __j = __first2; __j != __last2; ++__j) {
+ if (std::invoke(__pred, std::invoke(__proj1, *__first1), std::invoke(__proj2, *__j)))
+ return __first1;
+ }
+ }
+ return __first1;
+ }
+
+ template <input_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ forward_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Iter1 operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ return __find_first_of_impl(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
+ }
+
+ template <input_range _Range1,
+ forward_range _Range2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range1> operator()(
+ _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ return __find_first_of_impl(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __pred,
+ __proj1,
+ __proj2);
+ }
+};
+} // namespace __find_first_of
+
+inline namespace __cpo {
+inline constexpr auto find_first_of = __find_first_of::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FIND_FIRST_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_find_if.h b/libcxx/include/__cxx03/__algorithm/ranges_find_if.h
new file mode 100644
index 00000000000000..888f9ec3cb2d58
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_find_if.h
@@ -0,0 +1,75 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FIND_IF_H
+#define _LIBCPP___ALGORITHM_RANGES_FIND_IF_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Ip, class _Sp, class _Pred, class _Proj>
+_LIBCPP_HIDE_FROM_ABI constexpr _Ip __find_if_impl(_Ip __first, _Sp __last, _Pred& __pred, _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first)))
+ break;
+ }
+ return __first;
+}
+
+namespace __find_if {
+struct __fn {
+ template <input_iterator _Ip,
+ sentinel_for<_Ip> _Sp,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Ip, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Ip
+ operator()(_Ip __first, _Sp __last, _Pred __pred, _Proj __proj = {}) const {
+ return ranges::__find_if_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <input_range _Rp, class _Proj = identity, indirect_unary_predicate<projected<iterator_t<_Rp>, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp>
+ operator()(_Rp&& __r, _Pred __pred, _Proj __proj = {}) const {
+ return ranges::__find_if_impl(ranges::begin(__r), ranges::end(__r), __pred, __proj);
+ }
+};
+} // namespace __find_if
+
+inline namespace __cpo {
+inline constexpr auto find_if = __find_if::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FIND_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_find_if_not.h b/libcxx/include/__cxx03/__algorithm/ranges_find_if_not.h
new file mode 100644
index 00000000000000..ec19545b5a1b7a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_find_if_not.h
@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FIND_IF_NOT_H
+#define _LIBCPP___ALGORITHM_RANGES_FIND_IF_NOT_H
+
+#include <__algorithm/ranges_find_if.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __find_if_not {
+struct __fn {
+ template <input_iterator _Ip,
+ sentinel_for<_Ip> _Sp,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Ip, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Ip
+ operator()(_Ip __first, _Sp __last, _Pred __pred, _Proj __proj = {}) const {
+ auto __pred2 = [&](auto&& __e) -> bool { return !std::invoke(__pred, std::forward<decltype(__e)>(__e)); };
+ return ranges::__find_if_impl(std::move(__first), std::move(__last), __pred2, __proj);
+ }
+
+ template <input_range _Rp, class _Proj = identity, indirect_unary_predicate<projected<iterator_t<_Rp>, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp>
+ operator()(_Rp&& __r, _Pred __pred, _Proj __proj = {}) const {
+ auto __pred2 = [&](auto&& __e) -> bool { return !std::invoke(__pred, std::forward<decltype(__e)>(__e)); };
+ return ranges::__find_if_impl(ranges::begin(__r), ranges::end(__r), __pred2, __proj);
+ }
+};
+} // namespace __find_if_not
+
+inline namespace __cpo {
+inline constexpr auto find_if_not = __find_if_not::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FIND_IF_NOT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_find_last.h b/libcxx/include/__cxx03/__algorithm/ranges_find_last.h
new file mode 100644
index 00000000000000..95f7e77b8ccbea
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_find_last.h
@@ -0,0 +1,175 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FIND_LAST_H
+#define _LIBCPP___ALGORITHM_RANGES_FIND_LAST_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/next.h>
+#include <__iterator/prev.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/subrange.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Iter, class _Sent, class _Pred, class _Proj>
+_LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter>
+__find_last_impl(_Iter __first, _Sent __last, _Pred __pred, _Proj& __proj) {
+ if (__first == __last) {
+ return subrange<_Iter>(__first, __first);
+ }
+
+ if constexpr (bidirectional_iterator<_Iter>) {
+ auto __last_it = ranges::next(__first, __last);
+ for (auto __it = ranges::prev(__last_it); __it != __first; --__it) {
+ if (__pred(std::invoke(__proj, *__it))) {
+ return subrange<_Iter>(std::move(__it), std::move(__last_it));
+ }
+ }
+ if (__pred(std::invoke(__proj, *__first))) {
+ return subrange<_Iter>(std::move(__first), std::move(__last_it));
+ }
+ return subrange<_Iter>(__last_it, __last_it);
+ } else {
+ bool __found = false;
+ _Iter __found_it;
+ for (; __first != __last; ++__first) {
+ if (__pred(std::invoke(__proj, *__first))) {
+ __found = true;
+ __found_it = __first;
+ }
+ }
+
+ if (__found) {
+ return subrange<_Iter>(std::move(__found_it), std::move(__first));
+ } else {
+ return subrange<_Iter>(__first, __first);
+ }
+ }
+}
+
+namespace __find_last {
+struct __fn {
+ template <class _Type>
+ struct __op {
+ const _Type& __value;
+ template <class _Elem>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator()(_Elem&& __elem) const {
+ return std::forward<_Elem>(__elem) == __value;
+ }
+ };
+
+ template <forward_iterator _Iter, sentinel_for<_Iter> _Sent, class _Type, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<_Iter, _Proj>, const _Type*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr static subrange<_Iter>
+ operator()(_Iter __first, _Sent __last, const _Type& __value, _Proj __proj = {}) {
+ return ranges::__find_last_impl(std::move(__first), std::move(__last), __op<_Type>{__value}, __proj);
+ }
+
+ template <forward_range _Range, class _Type, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _Type*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr static borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, const _Type& __value, _Proj __proj = {}) {
+ return ranges::__find_last_impl(ranges::begin(__range), ranges::end(__range), __op<_Type>{__value}, __proj);
+ }
+};
+} // namespace __find_last
+
+namespace __find_last_if {
+struct __fn {
+ template <class _Pred>
+ struct __op {
+ _Pred& __pred;
+ template <class _Elem>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator()(_Elem&& __elem) const {
+ return std::invoke(__pred, std::forward<_Elem>(__elem));
+ }
+ };
+
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr static subrange<_Iter>
+ operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) {
+ return ranges::__find_last_impl(std::move(__first), std::move(__last), __op<_Pred>{__pred}, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr static borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) {
+ return ranges::__find_last_impl(ranges::begin(__range), ranges::end(__range), __op<_Pred>{__pred}, __proj);
+ }
+};
+} // namespace __find_last_if
+
+namespace __find_last_if_not {
+struct __fn {
+ template <class _Pred>
+ struct __op {
+ _Pred& __pred;
+ template <class _Elem>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator()(_Elem&& __elem) const {
+ return !std::invoke(__pred, std::forward<_Elem>(__elem));
+ }
+ };
+
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr static subrange<_Iter>
+ operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) {
+ return ranges::__find_last_impl(std::move(__first), std::move(__last), __op<_Pred>{__pred}, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr static borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) {
+ return ranges::__find_last_impl(ranges::begin(__range), ranges::end(__range), __op<_Pred>{__pred}, __proj);
+ }
+};
+} // namespace __find_last_if_not
+
+inline namespace __cpo {
+inline constexpr auto find_last = __find_last::__fn{};
+inline constexpr auto find_last_if = __find_last_if::__fn{};
+inline constexpr auto find_last_if_not = __find_last_if_not::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FIND_LAST_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_for_each.h b/libcxx/include/__cxx03/__algorithm/ranges_for_each.h
new file mode 100644
index 00000000000000..225dc774c8764a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_for_each.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FOR_EACH_H
+#define _LIBCPP___ALGORITHM_RANGES_FOR_EACH_H
+
+#include <__algorithm/in_fun_result.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Iter, class _Func>
+using for_each_result = in_fun_result<_Iter, _Func>;
+
+namespace __for_each {
+struct __fn {
+private:
+ template <class _Iter, class _Sent, class _Proj, class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr static for_each_result<_Iter, _Func>
+ __for_each_impl(_Iter __first, _Sent __last, _Func& __func, _Proj& __proj) {
+ for (; __first != __last; ++__first)
+ std::invoke(__func, std::invoke(__proj, *__first));
+ return {std::move(__first), std::move(__func)};
+ }
+
+public:
+ template <input_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirectly_unary_invocable<projected<_Iter, _Proj>> _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr for_each_result<_Iter, _Func>
+ operator()(_Iter __first, _Sent __last, _Func __func, _Proj __proj = {}) const {
+ return __for_each_impl(std::move(__first), std::move(__last), __func, __proj);
+ }
+
+ template <input_range _Range,
+ class _Proj = identity,
+ indirectly_unary_invocable<projected<iterator_t<_Range>, _Proj>> _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr for_each_result<borrowed_iterator_t<_Range>, _Func>
+ operator()(_Range&& __range, _Func __func, _Proj __proj = {}) const {
+ return __for_each_impl(ranges::begin(__range), ranges::end(__range), __func, __proj);
+ }
+};
+} // namespace __for_each
+
+inline namespace __cpo {
+inline constexpr auto for_each = __for_each::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FOR_EACH_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_for_each_n.h b/libcxx/include/__cxx03/__algorithm/ranges_for_each_n.h
new file mode 100644
index 00000000000000..d1fdca34cc5a19
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_for_each_n.h
@@ -0,0 +1,64 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
+#define _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
+
+#include <__algorithm/in_fun_result.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Iter, class _Func>
+using for_each_n_result = in_fun_result<_Iter, _Func>;
+
+namespace __for_each_n {
+struct __fn {
+ template <input_iterator _Iter, class _Proj = identity, indirectly_unary_invocable<projected<_Iter, _Proj>> _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr for_each_n_result<_Iter, _Func>
+ operator()(_Iter __first, iter_difference_t<_Iter> __count, _Func __func, _Proj __proj = {}) const {
+ while (__count-- > 0) {
+ std::invoke(__func, std::invoke(__proj, *__first));
+ ++__first;
+ }
+ return {std::move(__first), std::move(__func)};
+ }
+};
+} // namespace __for_each_n
+
+inline namespace __cpo {
+inline constexpr auto for_each_n = __for_each_n::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_generate.h b/libcxx/include/__cxx03/__algorithm/ranges_generate.h
new file mode 100644
index 00000000000000..e6467198e6ba2f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_generate.h
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_GENERATE_H
+#define _LIBCPP___ALGORITHM_RANGES_GENERATE_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/invocable.h>
+#include <__config>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __generate {
+
+struct __fn {
+ template <class _OutIter, class _Sent, class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _OutIter __generate_fn_impl(_OutIter __first, _Sent __last, _Func& __gen) {
+ for (; __first != __last; ++__first) {
+ *__first = __gen();
+ }
+
+ return __first;
+ }
+
+ template <input_or_output_iterator _OutIter, sentinel_for<_OutIter> _Sent, copy_constructible _Func>
+ requires invocable<_Func&> && indirectly_writable<_OutIter, invoke_result_t<_Func&>>
+ _LIBCPP_HIDE_FROM_ABI constexpr _OutIter operator()(_OutIter __first, _Sent __last, _Func __gen) const {
+ return __generate_fn_impl(std::move(__first), std::move(__last), __gen);
+ }
+
+ template <class _Range, copy_constructible _Func>
+ requires invocable<_Func&> && output_range<_Range, invoke_result_t<_Func&>>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range> operator()(_Range&& __range, _Func __gen) const {
+ return __generate_fn_impl(ranges::begin(__range), ranges::end(__range), __gen);
+ }
+};
+
+} // namespace __generate
+
+inline namespace __cpo {
+inline constexpr auto generate = __generate::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_GENERATE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_generate_n.h b/libcxx/include/__cxx03/__algorithm/ranges_generate_n.h
new file mode 100644
index 00000000000000..cd5fd7483ab2c6
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_generate_n.h
@@ -0,0 +1,65 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_GENERATE_N_H
+#define _LIBCPP___ALGORITHM_RANGES_GENERATE_N_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/invocable.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __generate_n {
+
+struct __fn {
+ template <input_or_output_iterator _OutIter, copy_constructible _Func>
+ requires invocable<_Func&> && indirectly_writable<_OutIter, invoke_result_t<_Func&>>
+ _LIBCPP_HIDE_FROM_ABI constexpr _OutIter
+ operator()(_OutIter __first, iter_difference_t<_OutIter> __n, _Func __gen) const {
+ for (; __n > 0; --__n) {
+ *__first = __gen();
+ ++__first;
+ }
+
+ return __first;
+ }
+};
+
+} // namespace __generate_n
+
+inline namespace __cpo {
+inline constexpr auto generate_n = __generate_n::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_GENERATE_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_includes.h b/libcxx/include/__cxx03/__algorithm/ranges_includes.h
new file mode 100644
index 00000000000000..c4c3b8ed088d31
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_includes.h
@@ -0,0 +1,98 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_INCLUDES_H
+#define _LIBCPP___ALGORITHM_RANGES_INCLUDES_H
+
+#include <__algorithm/includes.h>
+#include <__algorithm/make_projected.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __includes {
+
+struct __fn {
+ template <input_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ input_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Proj1 = identity,
+ class _Proj2 = identity,
+ indirect_strict_weak_order<projected<_Iter1, _Proj1>, projected<_Iter2, _Proj2>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ return std::__includes(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__comp),
+ std::move(__proj1),
+ std::move(__proj2));
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ class _Proj1 = identity,
+ class _Proj2 = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Range1>, _Proj1>, projected<iterator_t<_Range2>, _Proj2>>
+ _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Range1&& __range1, _Range2&& __range2, _Comp __comp = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ return std::__includes(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ std::move(__comp),
+ std::move(__proj1),
+ std::move(__proj2));
+ }
+};
+
+} // namespace __includes
+
+inline namespace __cpo {
+inline constexpr auto includes = __includes::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_INCLUDES_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_inplace_merge.h b/libcxx/include/__cxx03/__algorithm/ranges_inplace_merge.h
new file mode 100644
index 00000000000000..d94c0ad4656776
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_inplace_merge.h
@@ -0,0 +1,84 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_INPLACE_MERGE_H
+#define _LIBCPP___ALGORITHM_RANGES_INPLACE_MERGE_H
+
+#include <__algorithm/inplace_merge.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __inplace_merge {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto
+ __inplace_merge_impl(_Iter __first, _Iter __middle, _Sent __last, _Comp&& __comp, _Proj&& __proj) {
+ auto __last_iter = ranges::next(__middle, __last);
+ std::__inplace_merge<_RangeAlgPolicy>(
+ std::move(__first), std::move(__middle), __last_iter, std::__make_projected(__comp, __proj));
+ return __last_iter;
+ }
+
+ template <bidirectional_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI _Iter
+ operator()(_Iter __first, _Iter __middle, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __inplace_merge_impl(
+ std::move(__first), std::move(__middle), std::move(__last), std::move(__comp), std::move(__proj));
+ }
+
+ template <bidirectional_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI borrowed_iterator_t<_Range>
+ operator()(_Range&& __range, iterator_t<_Range> __middle, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __inplace_merge_impl(
+ ranges::begin(__range), std::move(__middle), ranges::end(__range), std::move(__comp), std::move(__proj));
+ }
+};
+
+} // namespace __inplace_merge
+
+inline namespace __cpo {
+inline constexpr auto inplace_merge = __inplace_merge::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_INPLACE_MERGE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_is_heap.h b/libcxx/include/__cxx03/__algorithm/ranges_is_heap.h
new file mode 100644
index 00000000000000..3d9e18ce1d9067
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_is_heap.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_IS_HEAP_H
+#define _LIBCPP___ALGORITHM_RANGES_IS_HEAP_H
+
+#include <__algorithm/is_heap_until.h>
+#include <__algorithm/make_projected.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __is_heap {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Comp>
+ _LIBCPP_HIDE_FROM_ABI constexpr static bool
+ __is_heap_fn_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+
+ auto __result = std::__is_heap_until(std::move(__first), std::move(__last_iter), __projected_comp);
+ return __result == __last;
+ }
+
+ template <random_access_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<_Iter, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __is_heap_fn_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Range&& __range, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __is_heap_fn_impl(ranges::begin(__range), ranges::end(__range), __comp, __proj);
+ }
+};
+
+} // namespace __is_heap
+
+inline namespace __cpo {
+inline constexpr auto is_heap = __is_heap::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_IS_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_is_heap_until.h b/libcxx/include/__cxx03/__algorithm/ranges_is_heap_until.h
new file mode 100644
index 00000000000000..7a2e1fc7705b6f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_is_heap_until.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_IS_HEAP_UNTIL_H
+#define _LIBCPP___ALGORITHM_RANGES_IS_HEAP_UNTIL_H
+
+#include <__algorithm/is_heap_until.h>
+#include <__algorithm/make_projected.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __is_heap_until {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Comp>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __is_heap_until_fn_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+
+ return std::__is_heap_until(std::move(__first), std::move(__last_iter), __projected_comp);
+ }
+
+ template <random_access_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<_Iter, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __is_heap_until_fn_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __range, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __is_heap_until_fn_impl(ranges::begin(__range), ranges::end(__range), __comp, __proj);
+ }
+};
+
+} // namespace __is_heap_until
+
+inline namespace __cpo {
+inline constexpr auto is_heap_until = __is_heap_until::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_IS_HEAP_UNTIL_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_is_partitioned.h b/libcxx/include/__cxx03/__algorithm/ranges_is_partitioned.h
new file mode 100644
index 00000000000000..5be6fba46fd9e2
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_is_partitioned.h
@@ -0,0 +1,86 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_IS_PARTITIONED_H
+#define _LIBCPP___ALGORITHM_RANGES_IS_PARTITIONED_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __is_partitioned {
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr static bool
+ __is_partitioned_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (!std::invoke(__pred, std::invoke(__proj, *__first)))
+ break;
+ }
+
+ if (__first == __last)
+ return true;
+ ++__first;
+
+ for (; __first != __last; ++__first) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first)))
+ return false;
+ }
+
+ return true;
+ }
+
+ template <input_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) const {
+ return __is_partitioned_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <input_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
+ return __is_partitioned_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+} // namespace __is_partitioned
+
+inline namespace __cpo {
+inline constexpr auto is_partitioned = __is_partitioned::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_IS_PARTITIONED_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_is_permutation.h b/libcxx/include/__cxx03/__algorithm/ranges_is_permutation.h
new file mode 100644
index 00000000000000..1f8d67007a5738
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_is_permutation.h
@@ -0,0 +1,107 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_IS_PERMUTATION_H
+#define _LIBCPP___ALGORITHM_RANGES_IS_PERMUTATION_H
+
+#include <__algorithm/is_permutation.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __is_permutation {
+struct __fn {
+ template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Proj1, class _Proj2, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr static bool __is_permutation_func_impl(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2) {
+ return std::__is_permutation<_RangeAlgPolicy>(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
+ }
+
+ template <
+ forward_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ forward_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Proj1 = identity,
+ class _Proj2 = identity,
+ indirect_equivalence_relation<projected<_Iter1, _Proj1>, projected<_Iter2, _Proj2>> _Pred = ranges::equal_to>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ return __is_permutation_func_impl(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
+ }
+
+ template <forward_range _Range1,
+ forward_range _Range2,
+ class _Proj1 = identity,
+ class _Proj2 = identity,
+ indirect_equivalence_relation<projected<iterator_t<_Range1>, _Proj1>,
+ projected<iterator_t<_Range2>, _Proj2>> _Pred = ranges::equal_to>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ if constexpr (sized_range<_Range1> && sized_range<_Range2>) {
+ if (ranges::distance(__range1) != ranges::distance(__range2))
+ return false;
+ }
+
+ return __is_permutation_func_impl(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __pred,
+ __proj1,
+ __proj2);
+ }
+};
+} // namespace __is_permutation
+
+inline namespace __cpo {
+inline constexpr auto is_permutation = __is_permutation::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_IS_PERMUTATION_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_is_sorted.h b/libcxx/include/__cxx03/__algorithm/ranges_is_sorted.h
new file mode 100644
index 00000000000000..5b88d422b4b091
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_is_sorted.h
@@ -0,0 +1,67 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP__ALGORITHM_RANGES_IS_SORTED_H
+#define _LIBCPP__ALGORITHM_RANGES_IS_SORTED_H
+
+#include <__algorithm/ranges_is_sorted_until.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __is_sorted {
+struct __fn {
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<_Iter, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return ranges::__is_sorted_until_impl(std::move(__first), __last, __comp, __proj) == __last;
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Range&& __range, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __last = ranges::end(__range);
+ return ranges::__is_sorted_until_impl(ranges::begin(__range), __last, __comp, __proj) == __last;
+ }
+};
+} // namespace __is_sorted
+
+inline namespace __cpo {
+inline constexpr auto is_sorted = __is_sorted::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP__ALGORITHM_RANGES_IS_SORTED_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_is_sorted_until.h b/libcxx/include/__cxx03/__algorithm/ranges_is_sorted_until.h
new file mode 100644
index 00000000000000..54de530c8b2fd8
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_is_sorted_until.h
@@ -0,0 +1,82 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP__ALGORITHM_RANGES_IS_SORTED_UNTIL_H
+#define _LIBCPP__ALGORITHM_RANGES_IS_SORTED_UNTIL_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Iter, class _Sent, class _Proj, class _Comp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Iter
+__is_sorted_until_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ if (__first == __last)
+ return __first;
+ auto __i = __first;
+ while (++__i != __last) {
+ if (std::invoke(__comp, std::invoke(__proj, *__i), std::invoke(__proj, *__first)))
+ return __i;
+ __first = __i;
+ }
+ return __i;
+}
+
+namespace __is_sorted_until {
+struct __fn {
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<_Iter, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return ranges::__is_sorted_until_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __range, _Comp __comp = {}, _Proj __proj = {}) const {
+ return ranges::__is_sorted_until_impl(ranges::begin(__range), ranges::end(__range), __comp, __proj);
+ }
+};
+} // namespace __is_sorted_until
+
+inline namespace __cpo {
+inline constexpr auto is_sorted_until = __is_sorted_until::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP__ALGORITHM_RANGES_IS_SORTED_UNTIL_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_iterator_concept.h b/libcxx/include/__cxx03/__algorithm/ranges_iterator_concept.h
new file mode 100644
index 00000000000000..2af891d3af005a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_iterator_concept.h
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_ITERATOR_CONCEPT_H
+#define _LIBCPP___ALGORITHM_RANGES_ITERATOR_CONCEPT_H
+
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/remove_cvref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _IterMaybeQualified>
+consteval auto __get_iterator_concept() {
+ using _Iter = __remove_cvref_t<_IterMaybeQualified>;
+
+ if constexpr (contiguous_iterator<_Iter>)
+ return contiguous_iterator_tag();
+ else if constexpr (random_access_iterator<_Iter>)
+ return random_access_iterator_tag();
+ else if constexpr (bidirectional_iterator<_Iter>)
+ return bidirectional_iterator_tag();
+ else if constexpr (forward_iterator<_Iter>)
+ return forward_iterator_tag();
+ else if constexpr (input_iterator<_Iter>)
+ return input_iterator_tag();
+}
+
+template <class _Iter>
+using __iterator_concept = decltype(__get_iterator_concept<_Iter>());
+
+} // namespace ranges
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_ITERATOR_CONCEPT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_lexicographical_compare.h b/libcxx/include/__cxx03/__algorithm/ranges_lexicographical_compare.h
new file mode 100644
index 00000000000000..6d82017e302a70
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_lexicographical_compare.h
@@ -0,0 +1,106 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_LEXICOGRAPHICAL_COMPARE_H
+#define _LIBCPP___ALGORITHM_RANGES_LEXICOGRAPHICAL_COMPARE_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __lexicographical_compare {
+struct __fn {
+ template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Proj1, class _Proj2, class _Comp>
+ _LIBCPP_HIDE_FROM_ABI constexpr static bool __lexicographical_compare_impl(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Comp& __comp,
+ _Proj1& __proj1,
+ _Proj2& __proj2) {
+ while (__first2 != __last2) {
+ if (__first1 == __last1 || std::invoke(__comp, std::invoke(__proj1, *__first1), std::invoke(__proj2, *__first2)))
+ return true;
+ if (std::invoke(__comp, std::invoke(__proj2, *__first2), std::invoke(__proj1, *__first1)))
+ return false;
+ ++__first1;
+ ++__first2;
+ }
+ return false;
+ }
+
+ template <input_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ input_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Proj1 = identity,
+ class _Proj2 = identity,
+ indirect_strict_weak_order<projected<_Iter1, _Proj1>, projected<_Iter2, _Proj2>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ return __lexicographical_compare_impl(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __comp, __proj1, __proj2);
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ class _Proj1 = identity,
+ class _Proj2 = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Range1>, _Proj1>, projected<iterator_t<_Range2>, _Proj2>>
+ _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
+ _Range1&& __range1, _Range2&& __range2, _Comp __comp = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ return __lexicographical_compare_impl(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __comp,
+ __proj1,
+ __proj2);
+ }
+};
+} // namespace __lexicographical_compare
+
+inline namespace __cpo {
+inline constexpr auto lexicographical_compare = __lexicographical_compare::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_LEXICOGRAPHICAL_COMPARE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_lower_bound.h b/libcxx/include/__cxx03/__algorithm/ranges_lower_bound.h
new file mode 100644
index 00000000000000..0651147e042495
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_lower_bound.h
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_LOWER_BOUND_H
+#define _LIBCPP___ALGORITHM_RANGES_LOWER_BOUND_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/lower_bound.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+namespace __lower_bound {
+struct __fn {
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<const _Type*, projected<_Iter, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, const _Type& __value, _Comp __comp = {}, _Proj __proj = {}) const {
+ return std::__lower_bound<_RangeAlgPolicy>(__first, __last, __value, __comp, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<const _Type*, projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, const _Type& __value, _Comp __comp = {}, _Proj __proj = {}) const {
+ return std::__lower_bound<_RangeAlgPolicy>(ranges::begin(__r), ranges::end(__r), __value, __comp, __proj);
+ }
+};
+} // namespace __lower_bound
+
+inline namespace __cpo {
+inline constexpr auto lower_bound = __lower_bound::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_LOWER_BOUND_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_make_heap.h b/libcxx/include/__cxx03/__algorithm/ranges_make_heap.h
new file mode 100644
index 00000000000000..fe9c024fbf8a83
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_make_heap.h
@@ -0,0 +1,85 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MAKE_HEAP_H
+#define _LIBCPP___ALGORITHM_RANGES_MAKE_HEAP_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_heap.h>
+#include <__algorithm/make_projected.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __make_heap {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __make_heap_fn_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+ std::__make_heap<_RangeAlgPolicy>(std::move(__first), __last_iter, __projected_comp);
+
+ return __last_iter;
+ }
+
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __make_heap_fn_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __make_heap_fn_impl(ranges::begin(__r), ranges::end(__r), __comp, __proj);
+ }
+};
+
+} // namespace __make_heap
+
+inline namespace __cpo {
+inline constexpr auto make_heap = __make_heap::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MAKE_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_max.h b/libcxx/include/__cxx03/__algorithm/ranges_max.h
new file mode 100644
index 00000000000000..d0ee6f314b0c3f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_max.h
@@ -0,0 +1,103 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MAX_H
+#define _LIBCPP___ALGORITHM_RANGES_MAX_H
+
+#include <__algorithm/ranges_min_element.h>
+#include <__assert>
+#include <__concepts/copyable.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <__utility/move.h>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __max {
+struct __fn {
+ template <class _Tp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Tp*, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr const _Tp&
+ operator()(_LIBCPP_LIFETIMEBOUND const _Tp& __a,
+ _LIBCPP_LIFETIMEBOUND const _Tp& __b,
+ _Comp __comp = {},
+ _Proj __proj = {}) const {
+ return std::invoke(__comp, std::invoke(__proj, __a), std::invoke(__proj, __b)) ? __b : __a;
+ }
+
+ template <copyable _Tp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Tp*, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp
+ operator()(initializer_list<_Tp> __il, _Comp __comp = {}, _Proj __proj = {}) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __il.begin() != __il.end(), "initializer_list must contain at least one element");
+
+ auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
+ return *ranges::__min_element_impl(__il.begin(), __il.end(), __comp_lhs_rhs_swapped, __proj);
+ }
+
+ template <input_range _Rp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
+ requires indirectly_copyable_storable<iterator_t<_Rp>, range_value_t<_Rp>*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr range_value_t<_Rp>
+ operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __first = ranges::begin(__r);
+ auto __last = ranges::end(__r);
+
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__first != __last, "range must contain at least one element");
+
+ if constexpr (forward_range<_Rp> && !__is_cheap_to_copy<range_value_t<_Rp>>) {
+ auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool {
+ return std::invoke(__comp, __rhs, __lhs);
+ };
+ return *ranges::__min_element_impl(std::move(__first), std::move(__last), __comp_lhs_rhs_swapped, __proj);
+ } else {
+ range_value_t<_Rp> __result = *__first;
+ while (++__first != __last) {
+ if (std::invoke(__comp, std::invoke(__proj, __result), std::invoke(__proj, *__first)))
+ __result = *__first;
+ }
+ return __result;
+ }
+ }
+};
+} // namespace __max
+
+inline namespace __cpo {
+inline constexpr auto max = __max::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MAX_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_max_element.h b/libcxx/include/__cxx03/__algorithm/ranges_max_element.h
new file mode 100644
index 00000000000000..c577309271165b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_max_element.h
@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
+#define _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
+
+#include <__algorithm/ranges_min_element.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __max_element {
+struct __fn {
+ template <forward_iterator _Ip,
+ sentinel_for<_Ip> _Sp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<_Ip, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Ip
+ operator()(_Ip __first, _Sp __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
+ return ranges::__min_element_impl(__first, __last, __comp_lhs_rhs_swapped, __proj);
+ }
+
+ template <forward_range _Rp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp>
+ operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
+ return ranges::__min_element_impl(ranges::begin(__r), ranges::end(__r), __comp_lhs_rhs_swapped, __proj);
+ }
+};
+} // namespace __max_element
+
+inline namespace __cpo {
+inline constexpr auto max_element = __max_element::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_merge.h b/libcxx/include/__cxx03/__algorithm/ranges_merge.h
new file mode 100644
index 00000000000000..bdf9a62d90bd24
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_merge.h
@@ -0,0 +1,138 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MERGE_H
+#define _LIBCPP___ALGORITHM_RANGES_MERGE_H
+
+#include <__algorithm/in_in_out_result.h>
+#include <__algorithm/ranges_copy.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/mergeable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter1, class _InIter2, class _OutIter>
+using merge_result = in_in_out_result<_InIter1, _InIter2, _OutIter>;
+
+namespace __merge {
+
+template < class _InIter1,
+ class _Sent1,
+ class _InIter2,
+ class _Sent2,
+ class _OutIter,
+ class _Comp,
+ class _Proj1,
+ class _Proj2>
+_LIBCPP_HIDE_FROM_ABI constexpr merge_result<__remove_cvref_t<_InIter1>,
+ __remove_cvref_t<_InIter2>,
+ __remove_cvref_t<_OutIter>>
+__merge_impl(_InIter1&& __first1,
+ _Sent1&& __last1,
+ _InIter2&& __first2,
+ _Sent2&& __last2,
+ _OutIter&& __result,
+ _Comp&& __comp,
+ _Proj1&& __proj1,
+ _Proj2&& __proj2) {
+ for (; __first1 != __last1 && __first2 != __last2; ++__result) {
+ if (std::invoke(__comp, std::invoke(__proj2, *__first2), std::invoke(__proj1, *__first1))) {
+ *__result = *__first2;
+ ++__first2;
+ } else {
+ *__result = *__first1;
+ ++__first1;
+ }
+ }
+ auto __ret1 = ranges::copy(std::move(__first1), std::move(__last1), std::move(__result));
+ auto __ret2 = ranges::copy(std::move(__first2), std::move(__last2), std::move(__ret1.out));
+ return {std::move(__ret1.in), std::move(__ret2.in), std::move(__ret2.out)};
+}
+
+struct __fn {
+ template <input_iterator _InIter1,
+ sentinel_for<_InIter1> _Sent1,
+ input_iterator _InIter2,
+ sentinel_for<_InIter2> _Sent2,
+ weakly_incrementable _OutIter,
+ class _Comp = less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr merge_result<_InIter1, _InIter2, _OutIter> operator()(
+ _InIter1 __first1,
+ _Sent1 __last1,
+ _InIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ return __merge::__merge_impl(__first1, __last1, __first2, __last2, __result, __comp, __proj1, __proj2);
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ weakly_incrementable _OutIter,
+ class _Comp = less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<iterator_t<_Range1>, iterator_t<_Range2>, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr merge_result<borrowed_iterator_t<_Range1>, borrowed_iterator_t<_Range2>, _OutIter>
+ operator()(_Range1&& __range1,
+ _Range2&& __range2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ return __merge::__merge_impl(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __result,
+ __comp,
+ __proj1,
+ __proj2);
+ }
+};
+
+} // namespace __merge
+
+inline namespace __cpo {
+inline constexpr auto merge = __merge::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MERGE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_min.h b/libcxx/include/__cxx03/__algorithm/ranges_min.h
new file mode 100644
index 00000000000000..cc569d2a060c22
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_min.h
@@ -0,0 +1,95 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MIN_H
+#define _LIBCPP___ALGORITHM_RANGES_MIN_H
+
+#include <__algorithm/ranges_min_element.h>
+#include <__assert>
+#include <__concepts/copyable.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __min {
+struct __fn {
+ template <class _Tp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Tp*, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr const _Tp&
+ operator()(_LIBCPP_LIFETIMEBOUND const _Tp& __a,
+ _LIBCPP_LIFETIMEBOUND const _Tp& __b,
+ _Comp __comp = {},
+ _Proj __proj = {}) const {
+ return std::invoke(__comp, std::invoke(__proj, __b), std::invoke(__proj, __a)) ? __b : __a;
+ }
+
+ template <copyable _Tp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Tp*, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp
+ operator()(initializer_list<_Tp> __il, _Comp __comp = {}, _Proj __proj = {}) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __il.begin() != __il.end(), "initializer_list must contain at least one element");
+ return *ranges::__min_element_impl(__il.begin(), __il.end(), __comp, __proj);
+ }
+
+ template <input_range _Rp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
+ requires indirectly_copyable_storable<iterator_t<_Rp>, range_value_t<_Rp>*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr range_value_t<_Rp>
+ operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __first = ranges::begin(__r);
+ auto __last = ranges::end(__r);
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__first != __last, "range must contain at least one element");
+ if constexpr (forward_range<_Rp> && !__is_cheap_to_copy<range_value_t<_Rp>>) {
+ return *ranges::__min_element_impl(__first, __last, __comp, __proj);
+ } else {
+ range_value_t<_Rp> __result = *__first;
+ while (++__first != __last) {
+ if (std::invoke(__comp, std::invoke(__proj, *__first), std::invoke(__proj, __result)))
+ __result = *__first;
+ }
+ return __result;
+ }
+ }
+};
+} // namespace __min
+
+inline namespace __cpo {
+inline constexpr auto min = __min::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MIN_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_min_element.h b/libcxx/include/__cxx03/__algorithm/ranges_min_element.h
new file mode 100644
index 00000000000000..588ef258e26f5d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_min_element.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MIN_ELEMENT_H
+#define _LIBCPP___ALGORITHM_RANGES_MIN_ELEMENT_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+// TODO(ranges): `ranges::min_element` can now simply delegate to `std::__min_element`.
+template <class _Ip, class _Sp, class _Proj, class _Comp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Ip __min_element_impl(_Ip __first, _Sp __last, _Comp& __comp, _Proj& __proj) {
+ if (__first == __last)
+ return __first;
+
+ _Ip __i = __first;
+ while (++__i != __last)
+ if (std::invoke(__comp, std::invoke(__proj, *__i), std::invoke(__proj, *__first)))
+ __first = __i;
+ return __first;
+}
+
+namespace __min_element {
+struct __fn {
+ template <forward_iterator _Ip,
+ sentinel_for<_Ip> _Sp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<_Ip, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Ip
+ operator()(_Ip __first, _Sp __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return ranges::__min_element_impl(__first, __last, __comp, __proj);
+ }
+
+ template <forward_range _Rp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp>
+ operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ return ranges::__min_element_impl(ranges::begin(__r), ranges::end(__r), __comp, __proj);
+ }
+};
+} // namespace __min_element
+
+inline namespace __cpo {
+inline constexpr auto min_element = __min_element::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MIN_ELEMENT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_minmax.h b/libcxx/include/__cxx03/__algorithm/ranges_minmax.h
new file mode 100644
index 00000000000000..09cbefd91a8c77
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_minmax.h
@@ -0,0 +1,175 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MINMAX_H
+#define _LIBCPP___ALGORITHM_RANGES_MINMAX_H
+
+#include <__algorithm/min_max_result.h>
+#include <__algorithm/minmax_element.h>
+#include <__assert>
+#include <__concepts/copyable.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/desugars_to.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+template <class _T1>
+using minmax_result = min_max_result<_T1>;
+
+namespace __minmax {
+struct __fn {
+ template <class _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Type*, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr ranges::minmax_result<const _Type&>
+ operator()(_LIBCPP_LIFETIMEBOUND const _Type& __a,
+ _LIBCPP_LIFETIMEBOUND const _Type& __b,
+ _Comp __comp = {},
+ _Proj __proj = {}) const {
+ if (std::invoke(__comp, std::invoke(__proj, __b), std::invoke(__proj, __a)))
+ return {__b, __a};
+ return {__a, __b};
+ }
+
+ template <copyable _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Type*, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr ranges::minmax_result<_Type>
+ operator()(initializer_list<_Type> __il, _Comp __comp = {}, _Proj __proj = {}) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __il.begin() != __il.end(), "initializer_list has to contain at least one element");
+ auto __iters = std::__minmax_element_impl(__il.begin(), __il.end(), __comp, __proj);
+ return ranges::minmax_result<_Type>{*__iters.first, *__iters.second};
+ }
+
+ template <input_range _Range,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ requires indirectly_copyable_storable<iterator_t<_Range>, range_value_t<_Range>*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr ranges::minmax_result<range_value_t<_Range>>
+ operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __first = ranges::begin(__r);
+ auto __last = ranges::end(__r);
+ using _ValueT = range_value_t<_Range>;
+
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__first != __last, "range has to contain at least one element");
+
+ // This optimiation is not in minmax_element because clang doesn't see through the pointers and as a result doesn't
+ // vectorize the code.
+ if constexpr (contiguous_range<_Range> && is_integral_v<_ValueT> &&
+ __is_cheap_to_copy<_ValueT> & __is_identity<_Proj>::value &&
+ __desugars_to_v<__less_tag, _Comp, _ValueT, _ValueT>) {
+ minmax_result<_ValueT> __result = {__r[0], __r[0]};
+ for (auto __e : __r) {
+ if (__e < __result.min)
+ __result.min = __e;
+ if (__result.max < __e)
+ __result.max = __e;
+ }
+ return __result;
+ } else if constexpr (forward_range<_Range>) {
+ // Special-case the one element case. Avoid repeatedly initializing objects from the result of an iterator
+ // dereference when doing so might not be idempotent. The `if constexpr` avoids the extra branch in cases where
+ // it's not needed.
+ if constexpr (!same_as<remove_cvref_t<range_reference_t<_Range>>, _ValueT> ||
+ is_rvalue_reference_v<range_reference_t<_Range>>) {
+ if (ranges::next(__first) == __last) {
+ // During initialization, members are allowed to refer to already initialized members
+ // (see http://eel.is/c++draft/dcl.init.aggr#6)
+ minmax_result<_ValueT> __result = {*__first, __result.min};
+ return __result;
+ }
+ }
+ auto __result = std::__minmax_element_impl(__first, __last, __comp, __proj);
+ return {*__result.first, *__result.second};
+ } else {
+ // input_iterators can't be copied, so the implementation for input_iterators has to store
+ // the values instead of a pointer to the correct values
+ auto __less = [&](auto&& __a, auto&& __b) -> bool {
+ return std::invoke(__comp,
+ std::invoke(__proj, std::forward<decltype(__a)>(__a)),
+ std::invoke(__proj, std::forward<decltype(__b)>(__b)));
+ };
+
+ // During initialization, members are allowed to refer to already initialized members
+ // (see http://eel.is/c++draft/dcl.init.aggr#6)
+ ranges::minmax_result<_ValueT> __result = {*__first, __result.min};
+ if (__first == __last || ++__first == __last)
+ return __result;
+
+ if (__less(*__first, __result.min))
+ __result.min = *__first;
+ else
+ __result.max = *__first;
+
+ while (++__first != __last) {
+ _ValueT __i = *__first;
+ if (++__first == __last) {
+ if (__less(__i, __result.min))
+ __result.min = __i;
+ else if (!__less(__i, __result.max))
+ __result.max = __i;
+ return __result;
+ }
+
+ if (__less(*__first, __i)) {
+ if (__less(*__first, __result.min))
+ __result.min = *__first;
+ if (!__less(__i, __result.max))
+ __result.max = std::move(__i);
+ } else {
+ if (__less(__i, __result.min))
+ __result.min = std::move(__i);
+ if (!__less(*__first, __result.max))
+ __result.max = *__first;
+ }
+ }
+ return __result;
+ }
+ }
+};
+} // namespace __minmax
+
+inline namespace __cpo {
+inline constexpr auto minmax = __minmax::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MINMAX_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_minmax_element.h b/libcxx/include/__cxx03/__algorithm/ranges_minmax_element.h
new file mode 100644
index 00000000000000..4bf6d2404e463d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_minmax_element.h
@@ -0,0 +1,78 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MINMAX_ELEMENT_H
+#define _LIBCPP___ALGORITHM_RANGES_MINMAX_ELEMENT_H
+
+#include <__algorithm/min_max_result.h>
+#include <__algorithm/minmax_element.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _T1>
+using minmax_element_result = min_max_result<_T1>;
+
+namespace __minmax_element {
+struct __fn {
+ template <forward_iterator _Ip,
+ sentinel_for<_Ip> _Sp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<_Ip, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr ranges::minmax_element_result<_Ip>
+ operator()(_Ip __first, _Sp __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret = std::__minmax_element_impl(std::move(__first), std::move(__last), __comp, __proj);
+ return {__ret.first, __ret.second};
+ }
+
+ template <forward_range _Rp,
+ class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr ranges::minmax_element_result<borrowed_iterator_t<_Rp>>
+ operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret = std::__minmax_element_impl(ranges::begin(__r), ranges::end(__r), __comp, __proj);
+ return {__ret.first, __ret.second};
+ }
+};
+} // namespace __minmax_element
+
+inline namespace __cpo {
+inline constexpr auto minmax_element = __minmax_element::__fn{};
+} // namespace __cpo
+
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MINMAX_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_mismatch.h b/libcxx/include/__cxx03/__algorithm/ranges_mismatch.h
new file mode 100644
index 00000000000000..c4bf0022a9bcc0
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_mismatch.h
@@ -0,0 +1,100 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MISMATCH_H
+#define _LIBCPP___ALGORITHM_RANGES_MISMATCH_H
+
+#include <__algorithm/in_in_result.h>
+#include <__algorithm/mismatch.h>
+#include <__algorithm/unwrap_range.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _I1, class _I2>
+using mismatch_result = in_in_result<_I1, _I2>;
+
+namespace __mismatch {
+struct __fn {
+ template <class _I1, class _S1, class _I2, class _S2, class _Pred, class _Proj1, class _Proj2>
+ static _LIBCPP_HIDE_FROM_ABI constexpr mismatch_result<_I1, _I2>
+ __go(_I1 __first1, _S1 __last1, _I2 __first2, _S2 __last2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ if constexpr (forward_iterator<_I1> && forward_iterator<_I2>) {
+ auto __range1 = std::__unwrap_range(__first1, __last1);
+ auto __range2 = std::__unwrap_range(__first2, __last2);
+ auto __res =
+ std::__mismatch(__range1.first, __range1.second, __range2.first, __range2.second, __pred, __proj1, __proj2);
+ return {std::__rewrap_range<_S1>(__first1, __res.first), std::__rewrap_range<_S2>(__first2, __res.second)};
+ } else {
+ auto __res = std::__mismatch(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
+ return {std::move(__res.first), std::move(__res.second)};
+ }
+ }
+
+ template <input_iterator _I1,
+ sentinel_for<_I1> _S1,
+ input_iterator _I2,
+ sentinel_for<_I2> _S2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<_I1, _I2, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr mismatch_result<_I1, _I2> operator()(
+ _I1 __first1, _S1 __last1, _I2 __first2, _S2 __last2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {})
+ const {
+ return __go(std::move(__first1), __last1, std::move(__first2), __last2, __pred, __proj1, __proj2);
+ }
+
+ template <input_range _R1,
+ input_range _R2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<iterator_t<_R1>, iterator_t<_R2>, _Pred, _Proj1, _Proj2>
+ [[nodiscard]]
+ _LIBCPP_HIDE_FROM_ABI constexpr mismatch_result<borrowed_iterator_t<_R1>, borrowed_iterator_t<_R2>>
+ operator()(_R1&& __r1, _R2&& __r2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ return __go(
+ ranges::begin(__r1), ranges::end(__r1), ranges::begin(__r2), ranges::end(__r2), __pred, __proj1, __proj2);
+ }
+};
+} // namespace __mismatch
+
+inline namespace __cpo {
+constexpr inline auto mismatch = __mismatch::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MISMATCH_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_move.h b/libcxx/include/__cxx03/__algorithm/ranges_move.h
new file mode 100644
index 00000000000000..be869f36c97304
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_move.h
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MOVE_H
+#define _LIBCPP___ALGORITHM_RANGES_MOVE_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/move.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using move_result = in_out_result<_InIter, _OutIter>;
+
+namespace __move {
+struct __fn {
+ template <class _InIter, class _Sent, class _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr static move_result<_InIter, _OutIter>
+ __move_impl(_InIter __first, _Sent __last, _OutIter __result) {
+ auto __ret = std::__move<_RangeAlgPolicy>(std::move(__first), std::move(__last), std::move(__result));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <input_iterator _InIter, sentinel_for<_InIter> _Sent, weakly_incrementable _OutIter>
+ requires indirectly_movable<_InIter, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr move_result<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+ return __move_impl(std::move(__first), std::move(__last), std::move(__result));
+ }
+
+ template <input_range _Range, weakly_incrementable _OutIter>
+ requires indirectly_movable<iterator_t<_Range>, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr move_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __range, _OutIter __result) const {
+ return __move_impl(ranges::begin(__range), ranges::end(__range), std::move(__result));
+ }
+};
+} // namespace __move
+
+inline namespace __cpo {
+inline constexpr auto move = __move::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MOVE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_move_backward.h b/libcxx/include/__cxx03/__algorithm/ranges_move_backward.h
new file mode 100644
index 00000000000000..6d4071a33b8125
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_move_backward.h
@@ -0,0 +1,76 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MOVE_BACKWARD_H
+#define _LIBCPP___ALGORITHM_RANGES_MOVE_BACKWARD_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/move_backward.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/next.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using move_backward_result = in_out_result<_InIter, _OutIter>;
+
+namespace __move_backward {
+struct __fn {
+ template <class _InIter, class _Sent, class _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr static move_backward_result<_InIter, _OutIter>
+ __move_backward_impl(_InIter __first, _Sent __last, _OutIter __result) {
+ auto __ret = std::__move_backward<_RangeAlgPolicy>(std::move(__first), std::move(__last), std::move(__result));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <bidirectional_iterator _InIter, sentinel_for<_InIter> _Sent, bidirectional_iterator _OutIter>
+ requires indirectly_movable<_InIter, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr move_backward_result<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+ return __move_backward_impl(std::move(__first), std::move(__last), std::move(__result));
+ }
+
+ template <bidirectional_range _Range, bidirectional_iterator _Iter>
+ requires indirectly_movable<iterator_t<_Range>, _Iter>
+ _LIBCPP_HIDE_FROM_ABI constexpr move_backward_result<borrowed_iterator_t<_Range>, _Iter>
+ operator()(_Range&& __range, _Iter __result) const {
+ return __move_backward_impl(ranges::begin(__range), ranges::end(__range), std::move(__result));
+ }
+};
+} // namespace __move_backward
+
+inline namespace __cpo {
+inline constexpr auto move_backward = __move_backward::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MOVE_BACKWARD_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_next_permutation.h b/libcxx/include/__cxx03/__algorithm/ranges_next_permutation.h
new file mode 100644
index 00000000000000..18535e0a6254a1
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_next_permutation.h
@@ -0,0 +1,78 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_NEXT_PERMUTATION_H
+#define _LIBCPP___ALGORITHM_RANGES_NEXT_PERMUTATION_H
+
+#include <__algorithm/in_found_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/next_permutation.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter>
+using next_permutation_result = in_found_result<_InIter>;
+
+namespace __next_permutation {
+
+struct __fn {
+ template <bidirectional_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr next_permutation_result<_Iter>
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __result = std::__next_permutation<_RangeAlgPolicy>(
+ std::move(__first), std::move(__last), std::__make_projected(__comp, __proj));
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+
+ template <bidirectional_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr next_permutation_result<borrowed_iterator_t<_Range>>
+ operator()(_Range&& __range, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __result = std::__next_permutation<_RangeAlgPolicy>(
+ ranges::begin(__range), ranges::end(__range), std::__make_projected(__comp, __proj));
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+};
+
+} // namespace __next_permutation
+
+inline namespace __cpo {
+constexpr inline auto next_permutation = __next_permutation::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_NEXT_PERMUTATION_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_none_of.h b/libcxx/include/__cxx03/__algorithm/ranges_none_of.h
new file mode 100644
index 00000000000000..7df3c1829fcfcb
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_none_of.h
@@ -0,0 +1,75 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_NONE_OF_H
+#define _LIBCPP___ALGORITHM_RANGES_NONE_OF_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __none_of {
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr static bool
+ __none_of_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first)))
+ return false;
+ }
+ return true;
+ }
+
+ template <input_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Iter __first, _Sent __last, _Pred __pred = {}, _Proj __proj = {}) const {
+ return __none_of_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <input_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
+ return __none_of_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+} // namespace __none_of
+
+inline namespace __cpo {
+inline constexpr auto none_of = __none_of::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_NONE_OF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_nth_element.h b/libcxx/include/__cxx03/__algorithm/ranges_nth_element.h
new file mode 100644
index 00000000000000..90ade9efe10da6
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_nth_element.h
@@ -0,0 +1,84 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_NTH_ELEMENT_H
+#define _LIBCPP___ALGORITHM_RANGES_NTH_ELEMENT_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/nth_element.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __nth_element {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __nth_element_fn_impl(_Iter __first, _Iter __nth, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+ std::__nth_element_impl<_RangeAlgPolicy>(std::move(__first), std::move(__nth), __last_iter, __projected_comp);
+
+ return __last_iter;
+ }
+
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Iter __nth, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __nth_element_fn_impl(std::move(__first), std::move(__nth), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, iterator_t<_Range> __nth, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __nth_element_fn_impl(ranges::begin(__r), std::move(__nth), ranges::end(__r), __comp, __proj);
+ }
+};
+
+} // namespace __nth_element
+
+inline namespace __cpo {
+inline constexpr auto nth_element = __nth_element::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_NTH_ELEMENT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_partial_sort.h b/libcxx/include/__cxx03/__algorithm/ranges_partial_sort.h
new file mode 100644
index 00000000000000..c67247d2e0a77e
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_partial_sort.h
@@ -0,0 +1,82 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_PARTIAL_SORT_H
+#define _LIBCPP___ALGORITHM_RANGES_PARTIAL_SORT_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/partial_sort.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __partial_sort {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __partial_sort_fn_impl(_Iter __first, _Iter __middle, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+ return std::__partial_sort<_RangeAlgPolicy>(std::move(__first), std::move(__middle), __last, __projected_comp);
+ }
+
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Iter __middle, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __partial_sort_fn_impl(std::move(__first), std::move(__middle), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, iterator_t<_Range> __middle, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __partial_sort_fn_impl(ranges::begin(__r), std::move(__middle), ranges::end(__r), __comp, __proj);
+ }
+};
+
+} // namespace __partial_sort
+
+inline namespace __cpo {
+inline constexpr auto partial_sort = __partial_sort::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_PARTIAL_SORT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_partial_sort_copy.h b/libcxx/include/__cxx03/__algorithm/ranges_partial_sort_copy.h
new file mode 100644
index 00000000000000..b3bdeb78fb6f65
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_partial_sort_copy.h
@@ -0,0 +1,114 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_PARTIAL_SORT_COPY_H
+#define _LIBCPP___ALGORITHM_RANGES_PARTIAL_SORT_COPY_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/partial_sort_copy.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using partial_sort_copy_result = in_out_result<_InIter, _OutIter>;
+
+namespace __partial_sort_copy {
+
+struct __fn {
+ template <input_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ random_access_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Comp = ranges::less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_copyable<_Iter1, _Iter2> && sortable<_Iter2, _Comp, _Proj2> &&
+ indirect_strict_weak_order<_Comp, projected<_Iter1, _Proj1>, projected<_Iter2, _Proj2>>
+ _LIBCPP_HIDE_FROM_ABI constexpr partial_sort_copy_result<_Iter1, _Iter2> operator()(
+ _Iter1 __first,
+ _Sent1 __last,
+ _Iter2 __result_first,
+ _Sent2 __result_last,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __result = std::__partial_sort_copy<_RangeAlgPolicy>(
+ std::move(__first),
+ std::move(__last),
+ std::move(__result_first),
+ std::move(__result_last),
+ __comp,
+ __proj1,
+ __proj2);
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+
+ template <input_range _Range1,
+ random_access_range _Range2,
+ class _Comp = ranges::less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_copyable<iterator_t<_Range1>, iterator_t<_Range2>> &&
+ sortable<iterator_t<_Range2>, _Comp, _Proj2> &&
+ indirect_strict_weak_order<_Comp,
+ projected<iterator_t<_Range1>, _Proj1>,
+ projected<iterator_t<_Range2>, _Proj2>>
+ _LIBCPP_HIDE_FROM_ABI constexpr partial_sort_copy_result<borrowed_iterator_t<_Range1>, borrowed_iterator_t<_Range2>>
+ operator()(
+ _Range1&& __range, _Range2&& __result_range, _Comp __comp = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ auto __result = std::__partial_sort_copy<_RangeAlgPolicy>(
+ ranges::begin(__range),
+ ranges::end(__range),
+ ranges::begin(__result_range),
+ ranges::end(__result_range),
+ __comp,
+ __proj1,
+ __proj2);
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+};
+
+} // namespace __partial_sort_copy
+
+inline namespace __cpo {
+inline constexpr auto partial_sort_copy = __partial_sort_copy::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_PARTIAL_SORT_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_partition.h b/libcxx/include/__cxx03/__algorithm/ranges_partition.h
new file mode 100644
index 00000000000000..a67ac4c967570f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_partition.h
@@ -0,0 +1,88 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_PARTITION_H
+#define _LIBCPP___ALGORITHM_RANGES_PARTITION_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/partition.h>
+#include <__algorithm/ranges_iterator_concept.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/permutable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/subrange.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __partition {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI static constexpr subrange<__remove_cvref_t<_Iter>>
+ __partition_fn_impl(_Iter&& __first, _Sent&& __last, _Pred&& __pred, _Proj&& __proj) {
+ auto&& __projected_pred = std::__make_projected(__pred, __proj);
+ auto __result = std::__partition<_RangeAlgPolicy>(
+ std::move(__first), std::move(__last), __projected_pred, __iterator_concept<_Iter>());
+
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+
+ template <permutable _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter>
+ operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) const {
+ return __partition_fn_impl(__first, __last, __pred, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ requires permutable<iterator_t<_Range>>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
+ return __partition_fn_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+
+} // namespace __partition
+
+inline namespace __cpo {
+inline constexpr auto partition = __partition::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_PARTITION_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_partition_copy.h b/libcxx/include/__cxx03/__algorithm/ranges_partition_copy.h
new file mode 100644
index 00000000000000..d60c865dd2a8a3
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_partition_copy.h
@@ -0,0 +1,110 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_PARTITION_COPY_H
+#define _LIBCPP___ALGORITHM_RANGES_PARTITION_COPY_H
+
+#include <__algorithm/in_out_out_result.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter1, class _OutIter2>
+using partition_copy_result = in_out_out_result<_InIter, _OutIter1, _OutIter2>;
+
+namespace __partition_copy {
+
+struct __fn {
+ // TODO(ranges): delegate to the classic algorithm.
+ template <class _InIter, class _Sent, class _OutIter1, class _OutIter2, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr static partition_copy_result<__remove_cvref_t<_InIter>,
+ __remove_cvref_t<_OutIter1>,
+ __remove_cvref_t<_OutIter2> >
+ __partition_copy_fn_impl(
+ _InIter&& __first,
+ _Sent&& __last,
+ _OutIter1&& __out_true,
+ _OutIter2&& __out_false,
+ _Pred& __pred,
+ _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first))) {
+ *__out_true = *__first;
+ ++__out_true;
+
+ } else {
+ *__out_false = *__first;
+ ++__out_false;
+ }
+ }
+
+ return {std::move(__first), std::move(__out_true), std::move(__out_false)};
+ }
+
+ template <input_iterator _InIter,
+ sentinel_for<_InIter> _Sent,
+ weakly_incrementable _OutIter1,
+ weakly_incrementable _OutIter2,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_InIter, _Proj>> _Pred>
+ requires indirectly_copyable<_InIter, _OutIter1> && indirectly_copyable<_InIter, _OutIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr partition_copy_result<_InIter, _OutIter1, _OutIter2> operator()(
+ _InIter __first, _Sent __last, _OutIter1 __out_true, _OutIter2 __out_false, _Pred __pred, _Proj __proj = {})
+ const {
+ return __partition_copy_fn_impl(
+ std::move(__first), std::move(__last), std::move(__out_true), std::move(__out_false), __pred, __proj);
+ }
+
+ template <input_range _Range,
+ weakly_incrementable _OutIter1,
+ weakly_incrementable _OutIter2,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter1> && indirectly_copyable<iterator_t<_Range>, _OutIter2>
+ _LIBCPP_HIDE_FROM_ABI constexpr partition_copy_result<borrowed_iterator_t<_Range>, _OutIter1, _OutIter2>
+ operator()(_Range&& __range, _OutIter1 __out_true, _OutIter2 __out_false, _Pred __pred, _Proj __proj = {}) const {
+ return __partition_copy_fn_impl(
+ ranges::begin(__range), ranges::end(__range), std::move(__out_true), std::move(__out_false), __pred, __proj);
+ }
+};
+
+} // namespace __partition_copy
+
+inline namespace __cpo {
+inline constexpr auto partition_copy = __partition_copy::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_PARTITION_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_partition_point.h b/libcxx/include/__cxx03/__algorithm/ranges_partition_point.h
new file mode 100644
index 00000000000000..c5b11b5fed192a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_partition_point.h
@@ -0,0 +1,93 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_PARTITION_POINT_H
+#define _LIBCPP___ALGORITHM_RANGES_PARTITION_POINT_H
+
+#include <__algorithm/half_positive.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __partition_point {
+
+struct __fn {
+ // TODO(ranges): delegate to the classic algorithm.
+ template <class _Iter, class _Sent, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __partition_point_fn_impl(_Iter&& __first, _Sent&& __last, _Pred& __pred, _Proj& __proj) {
+ auto __len = ranges::distance(__first, __last);
+
+ while (__len != 0) {
+ auto __half_len = std::__half_positive(__len);
+ auto __mid = ranges::next(__first, __half_len);
+
+ if (std::invoke(__pred, std::invoke(__proj, *__mid))) {
+ __first = ++__mid;
+ __len -= __half_len + 1;
+
+ } else {
+ __len = __half_len;
+ }
+ }
+
+ return __first;
+ }
+
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) const {
+ return __partition_point_fn_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
+ return __partition_point_fn_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+
+} // namespace __partition_point
+
+inline namespace __cpo {
+inline constexpr auto partition_point = __partition_point::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_PARTITION_POINT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_pop_heap.h b/libcxx/include/__cxx03/__algorithm/ranges_pop_heap.h
new file mode 100644
index 00000000000000..01f92c0f228887
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_pop_heap.h
@@ -0,0 +1,86 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_POP_HEAP_H
+#define _LIBCPP___ALGORITHM_RANGES_POP_HEAP_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/pop_heap.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __pop_heap {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __pop_heap_fn_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+ auto __len = __last_iter - __first;
+
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+ std::__pop_heap<_RangeAlgPolicy>(std::move(__first), __last_iter, __projected_comp, __len);
+
+ return __last_iter;
+ }
+
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __pop_heap_fn_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __pop_heap_fn_impl(ranges::begin(__r), ranges::end(__r), __comp, __proj);
+ }
+};
+
+} // namespace __pop_heap
+
+inline namespace __cpo {
+inline constexpr auto pop_heap = __pop_heap::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_POP_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_prev_permutation.h b/libcxx/include/__cxx03/__algorithm/ranges_prev_permutation.h
new file mode 100644
index 00000000000000..225cee9b75ec6b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_prev_permutation.h
@@ -0,0 +1,78 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_PREV_PERMUTATION_H
+#define _LIBCPP___ALGORITHM_RANGES_PREV_PERMUTATION_H
+
+#include <__algorithm/in_found_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/prev_permutation.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter>
+using prev_permutation_result = in_found_result<_InIter>;
+
+namespace __prev_permutation {
+
+struct __fn {
+ template <bidirectional_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr prev_permutation_result<_Iter>
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __result = std::__prev_permutation<_RangeAlgPolicy>(
+ std::move(__first), std::move(__last), std::__make_projected(__comp, __proj));
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+
+ template <bidirectional_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr prev_permutation_result<borrowed_iterator_t<_Range>>
+ operator()(_Range&& __range, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __result = std::__prev_permutation<_RangeAlgPolicy>(
+ ranges::begin(__range), ranges::end(__range), std::__make_projected(__comp, __proj));
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+};
+
+} // namespace __prev_permutation
+
+inline namespace __cpo {
+constexpr inline auto prev_permutation = __prev_permutation::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_PREV_PERMUTATION_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_push_heap.h b/libcxx/include/__cxx03/__algorithm/ranges_push_heap.h
new file mode 100644
index 00000000000000..9d187af38c5319
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_push_heap.h
@@ -0,0 +1,85 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_PUSH_HEAP_H
+#define _LIBCPP___ALGORITHM_RANGES_PUSH_HEAP_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/push_heap.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __push_heap {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __push_heap_fn_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+ std::__push_heap<_RangeAlgPolicy>(std::move(__first), __last_iter, __projected_comp);
+
+ return __last_iter;
+ }
+
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __push_heap_fn_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __push_heap_fn_impl(ranges::begin(__r), ranges::end(__r), __comp, __proj);
+ }
+};
+
+} // namespace __push_heap
+
+inline namespace __cpo {
+inline constexpr auto push_heap = __push_heap::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_PUSH_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_remove.h b/libcxx/include/__cxx03/__algorithm/ranges_remove.h
new file mode 100644
index 00000000000000..17c3a2c5cd06b6
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_remove.h
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REMOVE_H
+#define _LIBCPP___ALGORITHM_RANGES_REMOVE_H
+#include <__config>
+
+#include <__algorithm/ranges_remove_if.h>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/permutable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/subrange.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __remove {
+struct __fn {
+ template <permutable _Iter, sentinel_for<_Iter> _Sent, class _Type, class _Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<_Iter, _Proj>, const _Type*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter>
+ operator()(_Iter __first, _Sent __last, const _Type& __value, _Proj __proj = {}) const {
+ auto __pred = [&](auto&& __other) -> bool { return __value == __other; };
+ return ranges::__remove_if_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <forward_range _Range, class _Type, class _Proj = identity>
+ requires permutable<iterator_t<_Range>> &&
+ indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _Type*>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, const _Type& __value, _Proj __proj = {}) const {
+ auto __pred = [&](auto&& __other) -> bool { return __value == __other; };
+ return ranges::__remove_if_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+} // namespace __remove
+
+inline namespace __cpo {
+inline constexpr auto remove = __remove::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REMOVE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_remove_copy.h b/libcxx/include/__cxx03/__algorithm/ranges_remove_copy.h
new file mode 100644
index 00000000000000..84529eceac68c5
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_remove_copy.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REMOVE_COPY_H
+#define _LIBCPP___ALGORITHM_RANGES_REMOVE_COPY_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/ranges_remove_copy_if.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using remove_copy_result = in_out_result<_InIter, _OutIter>;
+
+namespace __remove_copy {
+
+struct __fn {
+ template <input_iterator _InIter,
+ sentinel_for<_InIter> _Sent,
+ weakly_incrementable _OutIter,
+ class _Type,
+ class _Proj = identity>
+ requires indirectly_copyable<_InIter, _OutIter> &&
+ indirect_binary_predicate<ranges::equal_to, projected<_InIter, _Proj>, const _Type*>
+ _LIBCPP_HIDE_FROM_ABI constexpr remove_copy_result<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result, const _Type& __value, _Proj __proj = {}) const {
+ auto __pred = [&](auto&& __val) -> bool { return __value == __val; };
+ return ranges::__remove_copy_if_impl(std::move(__first), std::move(__last), std::move(__result), __pred, __proj);
+ }
+
+ template <input_range _Range, weakly_incrementable _OutIter, class _Type, class _Proj = identity>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter> &&
+ indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _Type*>
+ _LIBCPP_HIDE_FROM_ABI constexpr remove_copy_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __range, _OutIter __result, const _Type& __value, _Proj __proj = {}) const {
+ auto __pred = [&](auto&& __val) -> bool { return __value == __val; };
+ return ranges::__remove_copy_if_impl(
+ ranges::begin(__range), ranges::end(__range), std::move(__result), __pred, __proj);
+ }
+};
+
+} // namespace __remove_copy
+
+inline namespace __cpo {
+inline constexpr auto remove_copy = __remove_copy::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REMOVE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_remove_copy_if.h b/libcxx/include/__cxx03/__algorithm/ranges_remove_copy_if.h
new file mode 100644
index 00000000000000..56fe017533120b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_remove_copy_if.h
@@ -0,0 +1,95 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REMOVE_COPY_IF_H
+#define _LIBCPP___ALGORITHM_RANGES_REMOVE_COPY_IF_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/remove_copy_if.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using remove_copy_if_result = in_out_result<_InIter, _OutIter>;
+
+template <class _InIter, class _Sent, class _OutIter, class _Proj, class _Pred>
+_LIBCPP_HIDE_FROM_ABI constexpr in_out_result<_InIter, _OutIter>
+__remove_copy_if_impl(_InIter __first, _Sent __last, _OutIter __result, _Pred& __pred, _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (!std::invoke(__pred, std::invoke(__proj, *__first))) {
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return {std::move(__first), std::move(__result)};
+}
+
+namespace __remove_copy_if {
+
+struct __fn {
+ template <input_iterator _InIter,
+ sentinel_for<_InIter> _Sent,
+ weakly_incrementable _OutIter,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_InIter, _Proj>> _Pred>
+ requires indirectly_copyable<_InIter, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr remove_copy_if_result<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result, _Pred __pred, _Proj __proj = {}) const {
+ return ranges::__remove_copy_if_impl(std::move(__first), std::move(__last), std::move(__result), __pred, __proj);
+ }
+
+ template <input_range _Range,
+ weakly_incrementable _OutIter,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr remove_copy_if_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __range, _OutIter __result, _Pred __pred, _Proj __proj = {}) const {
+ return ranges::__remove_copy_if_impl(
+ ranges::begin(__range), ranges::end(__range), std::move(__result), __pred, __proj);
+ }
+};
+
+} // namespace __remove_copy_if
+
+inline namespace __cpo {
+inline constexpr auto remove_copy_if = __remove_copy_if::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REMOVE_COPY_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_remove_if.h b/libcxx/include/__cxx03/__algorithm/ranges_remove_if.h
new file mode 100644
index 00000000000000..0ea5d9a01b8818
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_remove_if.h
@@ -0,0 +1,89 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REMOVE_IF_H
+#define _LIBCPP___ALGORITHM_RANGES_REMOVE_IF_H
+#include <__config>
+
+#include <__algorithm/ranges_find_if.h>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/permutable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/subrange.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Iter, class _Sent, class _Proj, class _Pred>
+_LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter>
+__remove_if_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {
+ auto __new_end = ranges::__find_if_impl(__first, __last, __pred, __proj);
+ if (__new_end == __last)
+ return {__new_end, __new_end};
+
+ _Iter __i = __new_end;
+ while (++__i != __last) {
+ if (!std::invoke(__pred, std::invoke(__proj, *__i))) {
+ *__new_end = ranges::iter_move(__i);
+ ++__new_end;
+ }
+ }
+ return {__new_end, __i};
+}
+
+namespace __remove_if {
+struct __fn {
+ template <permutable _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter>
+ operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) const {
+ return ranges::__remove_if_impl(std::move(__first), std::move(__last), __pred, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ requires permutable<iterator_t<_Range>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
+ return ranges::__remove_if_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+} // namespace __remove_if
+
+inline namespace __cpo {
+inline constexpr auto remove_if = __remove_if::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REMOVE_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_replace.h b/libcxx/include/__cxx03/__algorithm/ranges_replace.h
new file mode 100644
index 00000000000000..2b88dc032972f4
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_replace.h
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REPLACE_H
+#define _LIBCPP___ALGORITHM_RANGES_REPLACE_H
+
+#include <__algorithm/ranges_replace_if.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __replace {
+struct __fn {
+ template <input_iterator _Iter, sentinel_for<_Iter> _Sent, class _Type1, class _Type2, class _Proj = identity>
+ requires indirectly_writable<_Iter, const _Type2&> &&
+ indirect_binary_predicate<ranges::equal_to, projected<_Iter, _Proj>, const _Type1*>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter operator()(
+ _Iter __first, _Sent __last, const _Type1& __old_value, const _Type2& __new_value, _Proj __proj = {}) const {
+ auto __pred = [&](const auto& __val) -> bool { return __val == __old_value; };
+ return ranges::__replace_if_impl(std::move(__first), std::move(__last), __pred, __new_value, __proj);
+ }
+
+ template <input_range _Range, class _Type1, class _Type2, class _Proj = identity>
+ requires indirectly_writable<iterator_t<_Range>, const _Type2&> &&
+ indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _Type1*>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __range, const _Type1& __old_value, const _Type2& __new_value, _Proj __proj = {}) const {
+ auto __pred = [&](auto&& __val) -> bool { return __val == __old_value; };
+ return ranges::__replace_if_impl(ranges::begin(__range), ranges::end(__range), __pred, __new_value, __proj);
+ }
+};
+} // namespace __replace
+
+inline namespace __cpo {
+inline constexpr auto replace = __replace::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REPLACE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_replace_copy.h b/libcxx/include/__cxx03/__algorithm/ranges_replace_copy.h
new file mode 100644
index 00000000000000..633f993e5c9484
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_replace_copy.h
@@ -0,0 +1,93 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REPLACE_COPY_H
+#define _LIBCPP___ALGORITHM_RANGES_REPLACE_COPY_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/ranges_replace_copy_if.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using replace_copy_result = in_out_result<_InIter, _OutIter>;
+
+namespace __replace_copy {
+
+struct __fn {
+ template <input_iterator _InIter,
+ sentinel_for<_InIter> _Sent,
+ class _OldType,
+ class _NewType,
+ output_iterator<const _NewType&> _OutIter,
+ class _Proj = identity>
+ requires indirectly_copyable<_InIter, _OutIter> &&
+ indirect_binary_predicate<ranges::equal_to, projected<_InIter, _Proj>, const _OldType*>
+ _LIBCPP_HIDE_FROM_ABI constexpr replace_copy_result<_InIter, _OutIter>
+ operator()(_InIter __first,
+ _Sent __last,
+ _OutIter __result,
+ const _OldType& __old_value,
+ const _NewType& __new_value,
+ _Proj __proj = {}) const {
+ auto __pred = [&](const auto& __value) -> bool { return __value == __old_value; };
+ return ranges::__replace_copy_if_impl(
+ std::move(__first), std::move(__last), std::move(__result), __pred, __new_value, __proj);
+ }
+
+ template <input_range _Range,
+ class _OldType,
+ class _NewType,
+ output_iterator<const _NewType&> _OutIter,
+ class _Proj = identity>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter> &&
+ indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _OldType*>
+ _LIBCPP_HIDE_FROM_ABI constexpr replace_copy_result<borrowed_iterator_t<_Range>, _OutIter> operator()(
+ _Range&& __range, _OutIter __result, const _OldType& __old_value, const _NewType& __new_value, _Proj __proj = {})
+ const {
+ auto __pred = [&](const auto& __value) -> bool { return __value == __old_value; };
+ return ranges::__replace_copy_if_impl(
+ ranges::begin(__range), ranges::end(__range), std::move(__result), __pred, __new_value, __proj);
+ }
+};
+
+} // namespace __replace_copy
+
+inline namespace __cpo {
+inline constexpr auto replace_copy = __replace_copy::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REPLACE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_replace_copy_if.h b/libcxx/include/__cxx03/__algorithm/ranges_replace_copy_if.h
new file mode 100644
index 00000000000000..e065c3ac0acc90
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_replace_copy_if.h
@@ -0,0 +1,98 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REPLACE_COPY_IF_H
+#define _LIBCPP___ALGORITHM_RANGES_REPLACE_COPY_IF_H
+
+#include <__algorithm/in_out_result.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using replace_copy_if_result = in_out_result<_InIter, _OutIter>;
+
+template <class _InIter, class _Sent, class _OutIter, class _Pred, class _Type, class _Proj>
+_LIBCPP_HIDE_FROM_ABI constexpr replace_copy_if_result<_InIter, _OutIter> __replace_copy_if_impl(
+ _InIter __first, _Sent __last, _OutIter __result, _Pred& __pred, const _Type& __new_value, _Proj& __proj) {
+ while (__first != __last) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first)))
+ *__result = __new_value;
+ else
+ *__result = *__first;
+
+ ++__first;
+ ++__result;
+ }
+
+ return {std::move(__first), std::move(__result)};
+}
+
+namespace __replace_copy_if {
+
+struct __fn {
+ template <input_iterator _InIter,
+ sentinel_for<_InIter> _Sent,
+ class _Type,
+ output_iterator<const _Type&> _OutIter,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_InIter, _Proj>> _Pred>
+ requires indirectly_copyable<_InIter, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr replace_copy_if_result<_InIter, _OutIter> operator()(
+ _InIter __first, _Sent __last, _OutIter __result, _Pred __pred, const _Type& __new_value, _Proj __proj = {})
+ const {
+ return ranges::__replace_copy_if_impl(
+ std::move(__first), std::move(__last), std::move(__result), __pred, __new_value, __proj);
+ }
+
+ template <input_range _Range,
+ class _Type,
+ output_iterator<const _Type&> _OutIter,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr replace_copy_if_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __range, _OutIter __result, _Pred __pred, const _Type& __new_value, _Proj __proj = {}) const {
+ return ranges::__replace_copy_if_impl(
+ ranges::begin(__range), ranges::end(__range), std::move(__result), __pred, __new_value, __proj);
+ }
+};
+
+} // namespace __replace_copy_if
+
+inline namespace __cpo {
+inline constexpr auto replace_copy_if = __replace_copy_if::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REPLACE_COPY_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_replace_if.h b/libcxx/include/__cxx03/__algorithm/ranges_replace_if.h
new file mode 100644
index 00000000000000..6445f42aea1908
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_replace_if.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REPLACE_IF_H
+#define _LIBCPP___ALGORITHM_RANGES_REPLACE_IF_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Iter, class _Sent, class _Type, class _Proj, class _Pred>
+_LIBCPP_HIDE_FROM_ABI constexpr _Iter
+__replace_if_impl(_Iter __first, _Sent __last, _Pred& __pred, const _Type& __new_value, _Proj& __proj) {
+ for (; __first != __last; ++__first) {
+ if (std::invoke(__pred, std::invoke(__proj, *__first)))
+ *__first = __new_value;
+ }
+ return __first;
+}
+
+namespace __replace_if {
+struct __fn {
+ template <input_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Type,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ requires indirectly_writable<_Iter, const _Type&>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Pred __pred, const _Type& __new_value, _Proj __proj = {}) const {
+ return ranges::__replace_if_impl(std::move(__first), std::move(__last), __pred, __new_value, __proj);
+ }
+
+ template <input_range _Range,
+ class _Type,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ requires indirectly_writable<iterator_t<_Range>, const _Type&>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __range, _Pred __pred, const _Type& __new_value, _Proj __proj = {}) const {
+ return ranges::__replace_if_impl(ranges::begin(__range), ranges::end(__range), __pred, __new_value, __proj);
+ }
+};
+} // namespace __replace_if
+
+inline namespace __cpo {
+inline constexpr auto replace_if = __replace_if::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REPLACE_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_reverse.h b/libcxx/include/__cxx03/__algorithm/ranges_reverse.h
new file mode 100644
index 00000000000000..9ec865995b4a54
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_reverse.h
@@ -0,0 +1,79 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REVERSE_H
+#define _LIBCPP___ALGORITHM_RANGES_REVERSE_H
+
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/next.h>
+#include <__iterator/permutable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __reverse {
+struct __fn {
+ template <bidirectional_iterator _Iter, sentinel_for<_Iter> _Sent>
+ requires permutable<_Iter>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter operator()(_Iter __first, _Sent __last) const {
+ if constexpr (random_access_iterator<_Iter>) {
+ if (__first == __last)
+ return __first;
+
+ auto __end = ranges::next(__first, __last);
+ auto __ret = __end;
+
+ while (__first < --__end) {
+ ranges::iter_swap(__first, __end);
+ ++__first;
+ }
+ return __ret;
+ } else {
+ auto __end = ranges::next(__first, __last);
+ auto __ret = __end;
+
+ while (__first != __end) {
+ if (__first == --__end)
+ break;
+
+ ranges::iter_swap(__first, __end);
+ ++__first;
+ }
+ return __ret;
+ }
+ }
+
+ template <bidirectional_range _Range>
+ requires permutable<iterator_t<_Range>>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range> operator()(_Range&& __range) const {
+ return (*this)(ranges::begin(__range), ranges::end(__range));
+ }
+};
+} // namespace __reverse
+
+inline namespace __cpo {
+inline constexpr auto reverse = __reverse::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REVERSE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_reverse_copy.h b/libcxx/include/__cxx03/__algorithm/ranges_reverse_copy.h
new file mode 100644
index 00000000000000..60043787a71705
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_reverse_copy.h
@@ -0,0 +1,70 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_REVERSE_COPY_H
+#define _LIBCPP___ALGORITHM_RANGES_REVERSE_COPY_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/ranges_copy.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/next.h>
+#include <__iterator/reverse_iterator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__ranges/subrange.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using reverse_copy_result = in_out_result<_InIter, _OutIter>;
+
+namespace __reverse_copy {
+struct __fn {
+ template <bidirectional_iterator _InIter, sentinel_for<_InIter> _Sent, weakly_incrementable _OutIter>
+ requires indirectly_copyable<_InIter, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_copy_result<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+ return (*this)(subrange(std::move(__first), std::move(__last)), std::move(__result));
+ }
+
+ template <bidirectional_range _Range, weakly_incrementable _OutIter>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_copy_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __range, _OutIter __result) const {
+ auto __ret = ranges::copy(std::__reverse_range(__range), std::move(__result));
+ return {ranges::next(ranges::begin(__range), ranges::end(__range)), std::move(__ret.out)};
+ }
+};
+} // namespace __reverse_copy
+
+inline namespace __cpo {
+inline constexpr auto reverse_copy = __reverse_copy::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_REVERSE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_rotate.h b/libcxx/include/__cxx03/__algorithm/ranges_rotate.h
new file mode 100644
index 00000000000000..8d33a6f0799bf7
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_rotate.h
@@ -0,0 +1,71 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_ROTATE_H
+#define _LIBCPP___ALGORITHM_RANGES_ROTATE_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/ranges_iterator_concept.h>
+#include <__algorithm/rotate.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/permutable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/subrange.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __rotate {
+
+struct __fn {
+ template <class _Iter, class _Sent>
+ _LIBCPP_HIDE_FROM_ABI constexpr static subrange<_Iter> __rotate_fn_impl(_Iter __first, _Iter __middle, _Sent __last) {
+ auto __ret = std::__rotate<_RangeAlgPolicy>(std::move(__first), std::move(__middle), std::move(__last));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <permutable _Iter, sentinel_for<_Iter> _Sent>
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter> operator()(_Iter __first, _Iter __middle, _Sent __last) const {
+ return __rotate_fn_impl(std::move(__first), std::move(__middle), std::move(__last));
+ }
+
+ template <forward_range _Range>
+ requires permutable<iterator_t<_Range>>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, iterator_t<_Range> __middle) const {
+ return __rotate_fn_impl(ranges::begin(__range), std::move(__middle), ranges::end(__range));
+ }
+};
+
+} // namespace __rotate
+
+inline namespace __cpo {
+inline constexpr auto rotate = __rotate::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_ROTATE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_rotate_copy.h b/libcxx/include/__cxx03/__algorithm/ranges_rotate_copy.h
new file mode 100644
index 00000000000000..26fe110b538963
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_rotate_copy.h
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_ROTATE_COPY_H
+#define _LIBCPP___ALGORITHM_RANGES_ROTATE_COPY_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/ranges_copy.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using rotate_copy_result = in_out_result<_InIter, _OutIter>;
+
+namespace __rotate_copy {
+struct __fn {
+ template <forward_iterator _InIter, sentinel_for<_InIter> _Sent, weakly_incrementable _OutIter>
+ requires indirectly_copyable<_InIter, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr rotate_copy_result<_InIter, _OutIter>
+ operator()(_InIter __first, _InIter __middle, _Sent __last, _OutIter __result) const {
+ auto __res1 = ranges::copy(__middle, __last, std::move(__result));
+ auto __res2 = ranges::copy(__first, __middle, std::move(__res1.out));
+ return {std::move(__res1.in), std::move(__res2.out)};
+ }
+
+ template <forward_range _Range, weakly_incrementable _OutIter>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter>
+ _LIBCPP_HIDE_FROM_ABI constexpr rotate_copy_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __range, iterator_t<_Range> __middle, _OutIter __result) const {
+ return (*this)(ranges::begin(__range), std::move(__middle), ranges::end(__range), std::move(__result));
+ }
+};
+} // namespace __rotate_copy
+
+inline namespace __cpo {
+inline constexpr auto rotate_copy = __rotate_copy::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_ROTATE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_sample.h b/libcxx/include/__cxx03/__algorithm/ranges_sample.h
new file mode 100644
index 00000000000000..e4f60a7b66be2b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_sample.h
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SAMPLE_H
+#define _LIBCPP___ALGORITHM_RANGES_SAMPLE_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/sample.h>
+#include <__algorithm/uniform_random_bit_generator_adaptor.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__random/uniform_random_bit_generator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __sample {
+
+struct __fn {
+ template <input_iterator _Iter, sentinel_for<_Iter> _Sent, weakly_incrementable _OutIter, class _Gen>
+ requires(forward_iterator<_Iter> || random_access_iterator<_OutIter>) && indirectly_copyable<_Iter, _OutIter> &&
+ uniform_random_bit_generator<remove_reference_t<_Gen>>
+ _LIBCPP_HIDE_FROM_ABI _OutIter
+ operator()(_Iter __first, _Sent __last, _OutIter __out_first, iter_difference_t<_Iter> __n, _Gen&& __gen) const {
+ _ClassicGenAdaptor<_Gen> __adapted_gen(__gen);
+ return std::__sample<_RangeAlgPolicy>(
+ std::move(__first), std::move(__last), std::move(__out_first), __n, __adapted_gen);
+ }
+
+ template <input_range _Range, weakly_incrementable _OutIter, class _Gen>
+ requires(forward_range<_Range> || random_access_iterator<_OutIter>) &&
+ indirectly_copyable<iterator_t<_Range>, _OutIter> && uniform_random_bit_generator<remove_reference_t<_Gen>>
+ _LIBCPP_HIDE_FROM_ABI _OutIter
+ operator()(_Range&& __range, _OutIter __out_first, range_difference_t<_Range> __n, _Gen&& __gen) const {
+ return (*this)(
+ ranges::begin(__range), ranges::end(__range), std::move(__out_first), __n, std::forward<_Gen>(__gen));
+ }
+};
+
+} // namespace __sample
+
+inline namespace __cpo {
+inline constexpr auto sample = __sample::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SAMPLE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_search.h b/libcxx/include/__cxx03/__algorithm/ranges_search.h
new file mode 100644
index 00000000000000..55294c60631b18
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_search.h
@@ -0,0 +1,134 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SEARCH_H
+#define _LIBCPP___ALGORITHM_RANGES_SEARCH_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/search.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/size.h>
+#include <__ranges/subrange.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __search {
+struct __fn {
+ template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
+ _LIBCPP_HIDE_FROM_ABI static constexpr subrange<_Iter1> __ranges_search_impl(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2) {
+ if constexpr (sized_sentinel_for<_Sent2, _Iter2>) {
+ auto __size2 = ranges::distance(__first2, __last2);
+ if (__size2 == 0)
+ return {__first1, __first1};
+
+ if constexpr (sized_sentinel_for<_Sent1, _Iter1>) {
+ auto __size1 = ranges::distance(__first1, __last1);
+ if (__size1 < __size2) {
+ ranges::advance(__first1, __last1);
+ return {__first1, __first1};
+ }
+
+ if constexpr (random_access_iterator<_Iter1> && random_access_iterator<_Iter2>) {
+ auto __ret = std::__search_random_access_impl<_RangeAlgPolicy>(
+ __first1, __last1, __first2, __last2, __pred, __proj1, __proj2, __size1, __size2);
+ return {__ret.first, __ret.second};
+ }
+ }
+ }
+
+ auto __ret =
+ std::__search_forward_impl<_RangeAlgPolicy>(__first1, __last1, __first2, __last2, __pred, __proj1, __proj2);
+ return {__ret.first, __ret.second};
+ }
+
+ template <forward_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ forward_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter1> operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ return __ranges_search_impl(__first1, __last1, __first2, __last2, __pred, __proj1, __proj2);
+ }
+
+ template <forward_range _Range1,
+ forward_range _Range2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range1> operator()(
+ _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
+ auto __first1 = ranges::begin(__range1);
+ if constexpr (sized_range<_Range2>) {
+ auto __size2 = ranges::size(__range2);
+ if (__size2 == 0)
+ return {__first1, __first1};
+ if constexpr (sized_range<_Range1>) {
+ auto __size1 = ranges::size(__range1);
+ if (__size1 < __size2) {
+ ranges::advance(__first1, ranges::end(__range1));
+ return {__first1, __first1};
+ }
+ }
+ }
+
+ return __ranges_search_impl(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __pred,
+ __proj1,
+ __proj2);
+ }
+};
+} // namespace __search
+
+inline namespace __cpo {
+inline constexpr auto search = __search::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SEARCH_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_search_n.h b/libcxx/include/__cxx03/__algorithm/ranges_search_n.h
new file mode 100644
index 00000000000000..56e12755b9bf6b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_search_n.h
@@ -0,0 +1,116 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SEARCH_N_H
+#define _LIBCPP___ALGORITHM_RANGES_SEARCH_N_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/search_n.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/size.h>
+#include <__ranges/subrange.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __search_n {
+struct __fn {
+ template <class _Iter1, class _Sent1, class _SizeT, class _Type, class _Pred, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI static constexpr subrange<_Iter1> __ranges_search_n_impl(
+ _Iter1 __first, _Sent1 __last, _SizeT __count, const _Type& __value, _Pred& __pred, _Proj& __proj) {
+ if (__count == 0)
+ return {__first, __first};
+
+ if constexpr (sized_sentinel_for<_Sent1, _Iter1>) {
+ auto __size = ranges::distance(__first, __last);
+ if (__size < __count) {
+ ranges::advance(__first, __last);
+ return {__first, __first};
+ }
+
+ if constexpr (random_access_iterator<_Iter1>) {
+ auto __ret = std::__search_n_random_access_impl<_RangeAlgPolicy>(
+ __first, __last, __count, __value, __pred, __proj, __size);
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+ }
+
+ auto __ret = std::__search_n_forward_impl<_RangeAlgPolicy>(__first, __last, __count, __value, __pred, __proj);
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Type,
+ class _Pred = ranges::equal_to,
+ class _Proj = identity>
+ requires indirectly_comparable<_Iter, const _Type*, _Pred, _Proj>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter>
+ operator()(_Iter __first,
+ _Sent __last,
+ iter_difference_t<_Iter> __count,
+ const _Type& __value,
+ _Pred __pred = {},
+ _Proj __proj = _Proj{}) const {
+ return __ranges_search_n_impl(__first, __last, __count, __value, __pred, __proj);
+ }
+
+ template <forward_range _Range, class _Type, class _Pred = ranges::equal_to, class _Proj = identity>
+ requires indirectly_comparable<iterator_t<_Range>, const _Type*, _Pred, _Proj>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range> operator()(
+ _Range&& __range, range_difference_t<_Range> __count, const _Type& __value, _Pred __pred = {}, _Proj __proj = {})
+ const {
+ auto __first = ranges::begin(__range);
+ if (__count <= 0)
+ return {__first, __first};
+ if constexpr (sized_range<_Range>) {
+ auto __size1 = ranges::size(__range);
+ if (__size1 < static_cast<range_size_t<_Range>>(__count)) {
+ ranges::advance(__first, ranges::end(__range));
+ return {__first, __first};
+ }
+ }
+
+ return __ranges_search_n_impl(ranges::begin(__range), ranges::end(__range), __count, __value, __pred, __proj);
+ }
+};
+} // namespace __search_n
+
+inline namespace __cpo {
+inline constexpr auto search_n = __search_n::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SEARCH_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_set_difference.h b/libcxx/include/__cxx03/__algorithm/ranges_set_difference.h
new file mode 100644
index 00000000000000..0841fb4ffd0c06
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_set_difference.h
@@ -0,0 +1,109 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SET_DIFFERENCE_H
+#define _LIBCPP___ALGORITHM_RANGES_SET_DIFFERENCE_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/set_difference.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/mergeable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__type_traits/decay.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using set_difference_result = in_out_result<_InIter, _OutIter>;
+
+namespace __set_difference {
+
+struct __fn {
+ template <input_iterator _InIter1,
+ sentinel_for<_InIter1> _Sent1,
+ input_iterator _InIter2,
+ sentinel_for<_InIter2> _Sent2,
+ weakly_incrementable _OutIter,
+ class _Comp = less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr set_difference_result<_InIter1, _OutIter> operator()(
+ _InIter1 __first1,
+ _Sent1 __last1,
+ _InIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__set_difference<_RangeAlgPolicy>(
+ __first1, __last1, __first2, __last2, __result, ranges::__make_projected_comp(__comp, __proj1, __proj2));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ weakly_incrementable _OutIter,
+ class _Comp = less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<iterator_t<_Range1>, iterator_t<_Range2>, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr set_difference_result<borrowed_iterator_t<_Range1>, _OutIter>
+ operator()(_Range1&& __range1,
+ _Range2&& __range2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__set_difference<_RangeAlgPolicy>(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __result,
+ ranges::__make_projected_comp(__comp, __proj1, __proj2));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+};
+
+} // namespace __set_difference
+
+inline namespace __cpo {
+inline constexpr auto set_difference = __set_difference::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SET_DIFFERENCE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_set_intersection.h b/libcxx/include/__cxx03/__algorithm/ranges_set_intersection.h
new file mode 100644
index 00000000000000..9427379745b60f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_set_intersection.h
@@ -0,0 +1,114 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SET_INTERSECTION_H
+#define _LIBCPP___ALGORITHM_RANGES_SET_INTERSECTION_H
+
+#include <__algorithm/in_in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/set_intersection.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/mergeable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter1, class _InIter2, class _OutIter>
+using set_intersection_result = in_in_out_result<_InIter1, _InIter2, _OutIter>;
+
+namespace __set_intersection {
+
+struct __fn {
+ template <input_iterator _InIter1,
+ sentinel_for<_InIter1> _Sent1,
+ input_iterator _InIter2,
+ sentinel_for<_InIter2> _Sent2,
+ weakly_incrementable _OutIter,
+ class _Comp = less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr set_intersection_result<_InIter1, _InIter2, _OutIter> operator()(
+ _InIter1 __first1,
+ _Sent1 __last1,
+ _InIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__set_intersection<_RangeAlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ ranges::__make_projected_comp(__comp, __proj1, __proj2));
+ return {std::move(__ret.__in1_), std::move(__ret.__in2_), std::move(__ret.__out_)};
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ weakly_incrementable _OutIter,
+ class _Comp = less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<iterator_t<_Range1>, iterator_t<_Range2>, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr set_intersection_result<borrowed_iterator_t<_Range1>,
+ borrowed_iterator_t<_Range2>,
+ _OutIter>
+ operator()(_Range1&& __range1,
+ _Range2&& __range2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__set_intersection<_RangeAlgPolicy>(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ std::move(__result),
+ ranges::__make_projected_comp(__comp, __proj1, __proj2));
+ return {std::move(__ret.__in1_), std::move(__ret.__in2_), std::move(__ret.__out_)};
+ }
+};
+
+} // namespace __set_intersection
+
+inline namespace __cpo {
+inline constexpr auto set_intersection = __set_intersection::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SET_INTERSECTION_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_set_symmetric_difference.h b/libcxx/include/__cxx03/__algorithm/ranges_set_symmetric_difference.h
new file mode 100644
index 00000000000000..995eb0999d940a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_set_symmetric_difference.h
@@ -0,0 +1,114 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SET_SYMMETRIC_DIFFERENCE_H
+#define _LIBCPP___ALGORITHM_RANGES_SET_SYMMETRIC_DIFFERENCE_H
+
+#include <__algorithm/in_in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/set_symmetric_difference.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/mergeable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter1, class _InIter2, class _OutIter>
+using set_symmetric_difference_result = in_in_out_result<_InIter1, _InIter2, _OutIter>;
+
+namespace __set_symmetric_difference {
+
+struct __fn {
+ template <input_iterator _InIter1,
+ sentinel_for<_InIter1> _Sent1,
+ input_iterator _InIter2,
+ sentinel_for<_InIter2> _Sent2,
+ weakly_incrementable _OutIter,
+ class _Comp = ranges::less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr set_symmetric_difference_result<_InIter1, _InIter2, _OutIter> operator()(
+ _InIter1 __first1,
+ _Sent1 __last1,
+ _InIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__set_symmetric_difference<_RangeAlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ ranges::__make_projected_comp(__comp, __proj1, __proj2));
+ return {std::move(__ret.__in1_), std::move(__ret.__in2_), std::move(__ret.__out_)};
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ weakly_incrementable _OutIter,
+ class _Comp = ranges::less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<iterator_t<_Range1>, iterator_t<_Range2>, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr set_symmetric_difference_result<borrowed_iterator_t<_Range1>,
+ borrowed_iterator_t<_Range2>,
+ _OutIter>
+ operator()(_Range1&& __range1,
+ _Range2&& __range2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__set_symmetric_difference<_RangeAlgPolicy>(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ std::move(__result),
+ ranges::__make_projected_comp(__comp, __proj1, __proj2));
+ return {std::move(__ret.__in1_), std::move(__ret.__in2_), std::move(__ret.__out_)};
+ }
+};
+
+} // namespace __set_symmetric_difference
+
+inline namespace __cpo {
+inline constexpr auto set_symmetric_difference = __set_symmetric_difference::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SET_SYMMETRIC_DIFFERENCE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_set_union.h b/libcxx/include/__cxx03/__algorithm/ranges_set_union.h
new file mode 100644
index 00000000000000..e870e390cc6659
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_set_union.h
@@ -0,0 +1,115 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SET_UNION_H
+#define _LIBCPP___ALGORITHM_RANGES_SET_UNION_H
+
+#include <__algorithm/in_in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/set_union.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/mergeable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter1, class _InIter2, class _OutIter>
+using set_union_result = in_in_out_result<_InIter1, _InIter2, _OutIter>;
+
+namespace __set_union {
+
+struct __fn {
+ template <input_iterator _InIter1,
+ sentinel_for<_InIter1> _Sent1,
+ input_iterator _InIter2,
+ sentinel_for<_InIter2> _Sent2,
+ weakly_incrementable _OutIter,
+ class _Comp = ranges::less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr set_union_result<_InIter1, _InIter2, _OutIter> operator()(
+ _InIter1 __first1,
+ _Sent1 __last1,
+ _InIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__set_union<_RangeAlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ ranges::__make_projected_comp(__comp, __proj1, __proj2));
+ return {std::move(__ret.__in1_), std::move(__ret.__in2_), std::move(__ret.__out_)};
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ weakly_incrementable _OutIter,
+ class _Comp = ranges::less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires mergeable<iterator_t<_Range1>, iterator_t<_Range2>, _OutIter, _Comp, _Proj1, _Proj2>
+ _LIBCPP_HIDE_FROM_ABI constexpr set_union_result<borrowed_iterator_t<_Range1>, borrowed_iterator_t<_Range2>, _OutIter>
+ operator()(_Range1&& __range1,
+ _Range2&& __range2,
+ _OutIter __result,
+ _Comp __comp = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) const {
+ auto __ret = std::__set_union<_RangeAlgPolicy>(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ std::move(__result),
+ ranges::__make_projected_comp(__comp, __proj1, __proj2));
+ return {std::move(__ret.__in1_), std::move(__ret.__in2_), std::move(__ret.__out_)};
+ }
+};
+
+} // namespace __set_union
+
+inline namespace __cpo {
+inline constexpr auto set_union = __set_union::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SET_UNION_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_shuffle.h b/libcxx/include/__cxx03/__algorithm/ranges_shuffle.h
new file mode 100644
index 00000000000000..ab98ea22caabec
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_shuffle.h
@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SHUFFLE_H
+#define _LIBCPP___ALGORITHM_RANGES_SHUFFLE_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/shuffle.h>
+#include <__algorithm/uniform_random_bit_generator_adaptor.h>
+#include <__config>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/permutable.h>
+#include <__random/uniform_random_bit_generator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __shuffle {
+
+struct __fn {
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Gen>
+ requires permutable<_Iter> && uniform_random_bit_generator<remove_reference_t<_Gen>>
+ _LIBCPP_HIDE_FROM_ABI _Iter operator()(_Iter __first, _Sent __last, _Gen&& __gen) const {
+ _ClassicGenAdaptor<_Gen> __adapted_gen(__gen);
+ return std::__shuffle<_RangeAlgPolicy>(std::move(__first), std::move(__last), __adapted_gen);
+ }
+
+ template <random_access_range _Range, class _Gen>
+ requires permutable<iterator_t<_Range>> && uniform_random_bit_generator<remove_reference_t<_Gen>>
+ _LIBCPP_HIDE_FROM_ABI borrowed_iterator_t<_Range> operator()(_Range&& __range, _Gen&& __gen) const {
+ return (*this)(ranges::begin(__range), ranges::end(__range), std::forward<_Gen>(__gen));
+ }
+};
+
+} // namespace __shuffle
+
+inline namespace __cpo {
+inline constexpr auto shuffle = __shuffle::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SHUFFLE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_sort.h b/libcxx/include/__cxx03/__algorithm/ranges_sort.h
new file mode 100644
index 00000000000000..0296c146b3edee
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_sort.h
@@ -0,0 +1,84 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SORT_H
+#define _LIBCPP___ALGORITHM_RANGES_SORT_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/sort.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __sort {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __sort_fn_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+ std::__sort_impl<_RangeAlgPolicy>(std::move(__first), __last_iter, __projected_comp);
+
+ return __last_iter;
+ }
+
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __sort_fn_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __sort_fn_impl(ranges::begin(__r), ranges::end(__r), __comp, __proj);
+ }
+};
+
+} // namespace __sort
+
+inline namespace __cpo {
+inline constexpr auto sort = __sort::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SORT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_sort_heap.h b/libcxx/include/__cxx03/__algorithm/ranges_sort_heap.h
new file mode 100644
index 00000000000000..bab30df1708c75
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_sort_heap.h
@@ -0,0 +1,85 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SORT_HEAP_H
+#define _LIBCPP___ALGORITHM_RANGES_SORT_HEAP_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/sort_heap.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __sort_heap {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr static _Iter
+ __sort_heap_fn_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+ std::__sort_heap<_RangeAlgPolicy>(std::move(__first), __last_iter, __projected_comp);
+
+ return __last_iter;
+ }
+
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __sort_heap_fn_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __sort_heap_fn_impl(ranges::begin(__r), ranges::end(__r), __comp, __proj);
+ }
+};
+
+} // namespace __sort_heap
+
+inline namespace __cpo {
+inline constexpr auto sort_heap = __sort_heap::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SORT_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_stable_partition.h b/libcxx/include/__cxx03/__algorithm/ranges_stable_partition.h
new file mode 100644
index 00000000000000..f34027ff772c78
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_stable_partition.h
@@ -0,0 +1,92 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_STABLE_PARTITION_H
+#define _LIBCPP___ALGORITHM_RANGES_STABLE_PARTITION_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/ranges_iterator_concept.h>
+#include <__algorithm/stable_partition.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/permutable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__ranges/subrange.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __stable_partition {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Proj, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI static subrange<__remove_cvref_t<_Iter>>
+ __stable_partition_fn_impl(_Iter&& __first, _Sent&& __last, _Pred&& __pred, _Proj&& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+
+ auto&& __projected_pred = std::__make_projected(__pred, __proj);
+ auto __result = std::__stable_partition<_RangeAlgPolicy>(
+ std::move(__first), __last_iter, __projected_pred, __iterator_concept<_Iter>());
+
+ return {std::move(__result), std::move(__last_iter)};
+ }
+
+ template <bidirectional_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
+ requires permutable<_Iter>
+ _LIBCPP_HIDE_FROM_ABI subrange<_Iter> operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) const {
+ return __stable_partition_fn_impl(__first, __last, __pred, __proj);
+ }
+
+ template <bidirectional_range _Range,
+ class _Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
+ requires permutable<iterator_t<_Range>>
+ _LIBCPP_HIDE_FROM_ABI borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
+ return __stable_partition_fn_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
+ }
+};
+
+} // namespace __stable_partition
+
+inline namespace __cpo {
+inline constexpr auto stable_partition = __stable_partition::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_STABLE_PARTITION_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_stable_sort.h b/libcxx/include/__cxx03/__algorithm/ranges_stable_sort.h
new file mode 100644
index 00000000000000..93909e253cc0f2
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_stable_sort.h
@@ -0,0 +1,82 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_STABLE_SORT_H
+#define _LIBCPP___ALGORITHM_RANGES_STABLE_SORT_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/stable_sort.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/projected.h>
+#include <__iterator/sortable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __stable_sort {
+
+struct __fn {
+ template <class _Iter, class _Sent, class _Comp, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI static _Iter __stable_sort_fn_impl(_Iter __first, _Sent __last, _Comp& __comp, _Proj& __proj) {
+ auto __last_iter = ranges::next(__first, __last);
+
+ auto&& __projected_comp = std::__make_projected(__comp, __proj);
+ std::__stable_sort_impl<_RangeAlgPolicy>(std::move(__first), __last_iter, __projected_comp);
+
+ return __last_iter;
+ }
+
+ template <random_access_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<_Iter, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI _Iter operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __stable_sort_fn_impl(std::move(__first), std::move(__last), __comp, __proj);
+ }
+
+ template <random_access_range _Range, class _Comp = ranges::less, class _Proj = identity>
+ requires sortable<iterator_t<_Range>, _Comp, _Proj>
+ _LIBCPP_HIDE_FROM_ABI borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ return __stable_sort_fn_impl(ranges::begin(__r), ranges::end(__r), __comp, __proj);
+ }
+};
+
+} // namespace __stable_sort
+
+inline namespace __cpo {
+inline constexpr auto stable_sort = __stable_sort::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_STABLE_SORT_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_starts_with.h b/libcxx/include/__cxx03/__algorithm/ranges_starts_with.h
new file mode 100644
index 00000000000000..17084e4f24336a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_starts_with.h
@@ -0,0 +1,95 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_STARTS_WITH_H
+#define _LIBCPP___ALGORITHM_RANGES_STARTS_WITH_H
+
+#include <__algorithm/in_in_result.h>
+#include <__algorithm/ranges_mismatch.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __starts_with {
+struct __fn {
+ template <input_iterator _Iter1,
+ sentinel_for<_Iter1> _Sent1,
+ input_iterator _Iter2,
+ sentinel_for<_Iter2> _Sent2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr bool operator()(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred __pred = {},
+ _Proj1 __proj1 = {},
+ _Proj2 __proj2 = {}) {
+ return __mismatch::__fn::__go(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ __pred,
+ __proj1,
+ __proj2)
+ .in2 == __last2;
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ class _Pred = ranges::equal_to,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr bool
+ operator()(_Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) {
+ return __mismatch::__fn::__go(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ __pred,
+ __proj1,
+ __proj2)
+ .in2 == ranges::end(__range2);
+ }
+};
+} // namespace __starts_with
+inline namespace __cpo {
+inline constexpr auto starts_with = __starts_with::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_STARTS_WITH_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_swap_ranges.h b/libcxx/include/__cxx03/__algorithm/ranges_swap_ranges.h
new file mode 100644
index 00000000000000..b6d9f618395a5e
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_swap_ranges.h
@@ -0,0 +1,70 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_SWAP_RANGES_H
+#define _LIBCPP___ALGORITHM_RANGES_SWAP_RANGES_H
+
+#include <__algorithm/in_in_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/swap_ranges.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iter_swap.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _I1, class _I2>
+using swap_ranges_result = in_in_result<_I1, _I2>;
+
+namespace __swap_ranges {
+struct __fn {
+ template <input_iterator _I1, sentinel_for<_I1> _S1, input_iterator _I2, sentinel_for<_I2> _S2>
+ requires indirectly_swappable<_I1, _I2>
+ _LIBCPP_HIDE_FROM_ABI constexpr swap_ranges_result<_I1, _I2>
+ operator()(_I1 __first1, _S1 __last1, _I2 __first2, _S2 __last2) const {
+ auto __ret = std::__swap_ranges<_RangeAlgPolicy>(
+ std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <input_range _R1, input_range _R2>
+ requires indirectly_swappable<iterator_t<_R1>, iterator_t<_R2>>
+ _LIBCPP_HIDE_FROM_ABI constexpr swap_ranges_result<borrowed_iterator_t<_R1>, borrowed_iterator_t<_R2>>
+ operator()(_R1&& __r1, _R2&& __r2) const {
+ return operator()(ranges::begin(__r1), ranges::end(__r1), ranges::begin(__r2), ranges::end(__r2));
+ }
+};
+} // namespace __swap_ranges
+
+inline namespace __cpo {
+inline constexpr auto swap_ranges = __swap_ranges::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_SWAP_RANGES_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_transform.h b/libcxx/include/__cxx03/__algorithm/ranges_transform.h
new file mode 100644
index 00000000000000..7850ec4f846560
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_transform.h
@@ -0,0 +1,177 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_TRANSFORM_H
+#define _LIBCPP___ALGORITHM_RANGES_TRANSFORM_H
+
+#include <__algorithm/in_in_out_result.h>
+#include <__algorithm/in_out_result.h>
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Ip, class _Op>
+using unary_transform_result = in_out_result<_Ip, _Op>;
+
+template <class _I1, class _I2, class _O1>
+using binary_transform_result = in_in_out_result<_I1, _I2, _O1>;
+
+namespace __transform {
+struct __fn {
+private:
+ template <class _InIter, class _Sent, class _OutIter, class _Func, class _Proj>
+ _LIBCPP_HIDE_FROM_ABI static constexpr unary_transform_result<_InIter, _OutIter>
+ __unary(_InIter __first, _Sent __last, _OutIter __result, _Func& __operation, _Proj& __projection) {
+ while (__first != __last) {
+ *__result = std::invoke(__operation, std::invoke(__projection, *__first));
+ ++__first;
+ ++__result;
+ }
+
+ return {std::move(__first), std::move(__result)};
+ }
+
+ template <class _InIter1,
+ class _Sent1,
+ class _InIter2,
+ class _Sent2,
+ class _OutIter,
+ class _Func,
+ class _Proj1,
+ class _Proj2>
+ _LIBCPP_HIDE_FROM_ABI static constexpr binary_transform_result<_InIter1, _InIter2, _OutIter>
+ __binary(_InIter1 __first1,
+ _Sent1 __last1,
+ _InIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Func& __binary_operation,
+ _Proj1& __projection1,
+ _Proj2& __projection2) {
+ while (__first1 != __last1 && __first2 != __last2) {
+ *__result =
+ std::invoke(__binary_operation, std::invoke(__projection1, *__first1), std::invoke(__projection2, *__first2));
+ ++__first1;
+ ++__first2;
+ ++__result;
+ }
+ return {std::move(__first1), std::move(__first2), std::move(__result)};
+ }
+
+public:
+ template <input_iterator _InIter,
+ sentinel_for<_InIter> _Sent,
+ weakly_incrementable _OutIter,
+ copy_constructible _Func,
+ class _Proj = identity>
+ requires indirectly_writable<_OutIter, indirect_result_t<_Func&, projected<_InIter, _Proj>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr unary_transform_result<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result, _Func __operation, _Proj __proj = {}) const {
+ return __unary(std::move(__first), std::move(__last), std::move(__result), __operation, __proj);
+ }
+
+ template <input_range _Range, weakly_incrementable _OutIter, copy_constructible _Func, class _Proj = identity>
+ requires indirectly_writable<_OutIter, indirect_result_t<_Func, projected<iterator_t<_Range>, _Proj>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr unary_transform_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __range, _OutIter __result, _Func __operation, _Proj __projection = {}) const {
+ return __unary(ranges::begin(__range), ranges::end(__range), std::move(__result), __operation, __projection);
+ }
+
+ template <input_iterator _InIter1,
+ sentinel_for<_InIter1> _Sent1,
+ input_iterator _InIter2,
+ sentinel_for<_InIter2> _Sent2,
+ weakly_incrementable _OutIter,
+ copy_constructible _Func,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_writable<_OutIter,
+ indirect_result_t<_Func&, projected<_InIter1, _Proj1>, projected<_InIter2, _Proj2>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr binary_transform_result<_InIter1, _InIter2, _OutIter> operator()(
+ _InIter1 __first1,
+ _Sent1 __last1,
+ _InIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Func __binary_operation,
+ _Proj1 __projection1 = {},
+ _Proj2 __projection2 = {}) const {
+ return __binary(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ __binary_operation,
+ __projection1,
+ __projection2);
+ }
+
+ template <input_range _Range1,
+ input_range _Range2,
+ weakly_incrementable _OutIter,
+ copy_constructible _Func,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+ requires indirectly_writable<
+ _OutIter,
+ indirect_result_t<_Func&, projected<iterator_t<_Range1>, _Proj1>, projected<iterator_t<_Range2>, _Proj2>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr binary_transform_result<borrowed_iterator_t<_Range1>,
+ borrowed_iterator_t<_Range2>,
+ _OutIter>
+ operator()(_Range1&& __range1,
+ _Range2&& __range2,
+ _OutIter __result,
+ _Func __binary_operation,
+ _Proj1 __projection1 = {},
+ _Proj2 __projection2 = {}) const {
+ return __binary(
+ ranges::begin(__range1),
+ ranges::end(__range1),
+ ranges::begin(__range2),
+ ranges::end(__range2),
+ std::move(__result),
+ __binary_operation,
+ __projection1,
+ __projection2);
+ }
+};
+} // namespace __transform
+
+inline namespace __cpo {
+inline constexpr auto transform = __transform::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_TRANSFORM_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_unique.h b/libcxx/include/__cxx03/__algorithm/ranges_unique.h
new file mode 100644
index 00000000000000..7a9b7843218737
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_unique.h
@@ -0,0 +1,82 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_UNIQUE_H
+#define _LIBCPP___ALGORITHM_RANGES_UNIQUE_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/unique.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/permutable.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__ranges/subrange.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __unique {
+
+struct __fn {
+ template <permutable _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirect_equivalence_relation<projected<_Iter, _Proj>> _Comp = ranges::equal_to>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter>
+ operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret =
+ std::__unique<_RangeAlgPolicy>(std::move(__first), std::move(__last), std::__make_projected(__comp, __proj));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <forward_range _Range,
+ class _Proj = identity,
+ indirect_equivalence_relation<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::equal_to>
+ requires permutable<iterator_t<_Range>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range>
+ operator()(_Range&& __range, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret = std::__unique<_RangeAlgPolicy>(
+ ranges::begin(__range), ranges::end(__range), std::__make_projected(__comp, __proj));
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+};
+
+} // namespace __unique
+
+inline namespace __cpo {
+inline constexpr auto unique = __unique::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_UNIQUE_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_unique_copy.h b/libcxx/include/__cxx03/__algorithm/ranges_unique_copy.h
new file mode 100644
index 00000000000000..61133885ae809d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_unique_copy.h
@@ -0,0 +1,120 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_UNIQUE_COPY_H
+#define _LIBCPP___ALGORITHM_RANGES_UNIQUE_COPY_H
+
+#include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/make_projected.h>
+#include <__algorithm/unique_copy.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _InIter, class _OutIter>
+using unique_copy_result = in_out_result<_InIter, _OutIter>;
+
+namespace __unique_copy {
+
+template <class _InIter, class _OutIter>
+concept __can_reread_from_output = (input_iterator<_OutIter> && same_as<iter_value_t<_InIter>, iter_value_t<_OutIter>>);
+
+struct __fn {
+ template <class _InIter, class _OutIter>
+ static consteval auto __get_algo_tag() {
+ if constexpr (forward_iterator<_InIter>) {
+ return __unique_copy_tags::__reread_from_input_tag{};
+ } else if constexpr (__can_reread_from_output<_InIter, _OutIter>) {
+ return __unique_copy_tags::__reread_from_output_tag{};
+ } else if constexpr (indirectly_copyable_storable<_InIter, _OutIter>) {
+ return __unique_copy_tags::__read_from_tmp_value_tag{};
+ }
+ }
+
+ template <class _InIter, class _OutIter>
+ using __algo_tag_t = decltype(__get_algo_tag<_InIter, _OutIter>());
+
+ template <input_iterator _InIter,
+ sentinel_for<_InIter> _Sent,
+ weakly_incrementable _OutIter,
+ class _Proj = identity,
+ indirect_equivalence_relation<projected<_InIter, _Proj>> _Comp = ranges::equal_to>
+ requires indirectly_copyable<_InIter, _OutIter> &&
+ (forward_iterator<_InIter> ||
+ (input_iterator<_OutIter> && same_as<iter_value_t<_InIter>, iter_value_t<_OutIter>>) ||
+ indirectly_copyable_storable<_InIter, _OutIter>)
+ _LIBCPP_HIDE_FROM_ABI constexpr unique_copy_result<_InIter, _OutIter>
+ operator()(_InIter __first, _Sent __last, _OutIter __result, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret = std::__unique_copy<_RangeAlgPolicy>(
+ std::move(__first),
+ std::move(__last),
+ std::move(__result),
+ std::__make_projected(__comp, __proj),
+ __algo_tag_t<_InIter, _OutIter>());
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+
+ template <input_range _Range,
+ weakly_incrementable _OutIter,
+ class _Proj = identity,
+ indirect_equivalence_relation<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::equal_to>
+ requires indirectly_copyable<iterator_t<_Range>, _OutIter> &&
+ (forward_iterator<iterator_t<_Range>> ||
+ (input_iterator<_OutIter> && same_as<range_value_t<_Range>, iter_value_t<_OutIter>>) ||
+ indirectly_copyable_storable<iterator_t<_Range>, _OutIter>)
+ _LIBCPP_HIDE_FROM_ABI constexpr unique_copy_result<borrowed_iterator_t<_Range>, _OutIter>
+ operator()(_Range&& __range, _OutIter __result, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __ret = std::__unique_copy<_RangeAlgPolicy>(
+ ranges::begin(__range),
+ ranges::end(__range),
+ std::move(__result),
+ std::__make_projected(__comp, __proj),
+ __algo_tag_t<iterator_t<_Range>, _OutIter>());
+ return {std::move(__ret.first), std::move(__ret.second)};
+ }
+};
+
+} // namespace __unique_copy
+
+inline namespace __cpo {
+inline constexpr auto unique_copy = __unique_copy::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_RANGES_UNIQUE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/ranges_upper_bound.h b/libcxx/include/__cxx03/__algorithm/ranges_upper_bound.h
new file mode 100644
index 00000000000000..fa6fa7f70ed5a7
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/ranges_upper_bound.h
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_UPPER_BOUND_H
+#define _LIBCPP___ALGORITHM_RANGES_UPPER_BOUND_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/lower_bound.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+namespace __upper_bound {
+struct __fn {
+ template <forward_iterator _Iter,
+ sentinel_for<_Iter> _Sent,
+ class _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<const _Type*, projected<_Iter, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Iter
+ operator()(_Iter __first, _Sent __last, const _Type& __value, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __comp_lhs_rhs_swapped = [&](const auto& __lhs, const auto& __rhs) -> bool {
+ return !std::invoke(__comp, __rhs, __lhs);
+ };
+
+ return std::__lower_bound<_RangeAlgPolicy>(__first, __last, __value, __comp_lhs_rhs_swapped, __proj);
+ }
+
+ template <forward_range _Range,
+ class _Type,
+ class _Proj = identity,
+ indirect_strict_weak_order<const _Type*, projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range>
+ operator()(_Range&& __r, const _Type& __value, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __comp_lhs_rhs_swapped = [&](const auto& __lhs, const auto& __rhs) -> bool {
+ return !std::invoke(__comp, __rhs, __lhs);
+ };
+
+ return std::__lower_bound<_RangeAlgPolicy>(
+ ranges::begin(__r), ranges::end(__r), __value, __comp_lhs_rhs_swapped, __proj);
+ }
+};
+} // namespace __upper_bound
+
+inline namespace __cpo {
+inline constexpr auto upper_bound = __upper_bound::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___ALGORITHM_RANGES_UPPER_BOUND_H
diff --git a/libcxx/include/__cxx03/__algorithm/remove.h b/libcxx/include/__cxx03/__algorithm/remove.h
new file mode 100644
index 00000000000000..fd01c23cb6708a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/remove.h
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REMOVE_H
+#define _LIBCPP___ALGORITHM_REMOVE_H
+
+#include <__algorithm/find.h>
+#include <__algorithm/find_if.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+remove(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ __first = std::find(__first, __last, __value);
+ if (__first != __last) {
+ _ForwardIterator __i = __first;
+ while (++__i != __last) {
+ if (!(*__i == __value)) {
+ *__first = std::move(*__i);
+ ++__first;
+ }
+ }
+ }
+ return __first;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_REMOVE_H
diff --git a/libcxx/include/__cxx03/__algorithm/remove_copy.h b/libcxx/include/__cxx03/__algorithm/remove_copy.h
new file mode 100644
index 00000000000000..7be4c166ce3d71
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/remove_copy.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REMOVE_COPY_H
+#define _LIBCPP___ALGORITHM_REMOVE_COPY_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+remove_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, const _Tp& __value) {
+ for (; __first != __last; ++__first) {
+ if (!(*__first == __value)) {
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_REMOVE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/remove_copy_if.h b/libcxx/include/__cxx03/__algorithm/remove_copy_if.h
new file mode 100644
index 00000000000000..dcafed169157d9
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/remove_copy_if.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REMOVE_COPY_IF_H
+#define _LIBCPP___ALGORITHM_REMOVE_COPY_IF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+remove_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Predicate __pred) {
+ for (; __first != __last; ++__first) {
+ if (!__pred(*__first)) {
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_REMOVE_COPY_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/remove_if.h b/libcxx/include/__cxx03/__algorithm/remove_if.h
new file mode 100644
index 00000000000000..b14f3c0efa7e97
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/remove_if.h
@@ -0,0 +1,45 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REMOVE_IF_H
+#define _LIBCPP___ALGORITHM_REMOVE_IF_H
+
+#include <__algorithm/find_if.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Predicate>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+remove_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ __first = std::find_if<_ForwardIterator, _Predicate&>(__first, __last, __pred);
+ if (__first != __last) {
+ _ForwardIterator __i = __first;
+ while (++__i != __last) {
+ if (!__pred(*__i)) {
+ *__first = std::move(*__i);
+ ++__first;
+ }
+ }
+ }
+ return __first;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_REMOVE_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/replace.h b/libcxx/include/__cxx03/__algorithm/replace.h
new file mode 100644
index 00000000000000..8057c78686e111
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/replace.h
@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REPLACE_H
+#define _LIBCPP___ALGORITHM_REPLACE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+replace(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __old_value, const _Tp& __new_value) {
+ for (; __first != __last; ++__first)
+ if (*__first == __old_value)
+ *__first = __new_value;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_REPLACE_H
diff --git a/libcxx/include/__cxx03/__algorithm/replace_copy.h b/libcxx/include/__cxx03/__algorithm/replace_copy.h
new file mode 100644
index 00000000000000..9a2258d9f58edd
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/replace_copy.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REPLACE_COPY_H
+#define _LIBCPP___ALGORITHM_REPLACE_COPY_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator replace_copy(
+ _InputIterator __first,
+ _InputIterator __last,
+ _OutputIterator __result,
+ const _Tp& __old_value,
+ const _Tp& __new_value) {
+ for (; __first != __last; ++__first, (void)++__result)
+ if (*__first == __old_value)
+ *__result = __new_value;
+ else
+ *__result = *__first;
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_REPLACE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/replace_copy_if.h b/libcxx/include/__cxx03/__algorithm/replace_copy_if.h
new file mode 100644
index 00000000000000..c2ed30f08d598b
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/replace_copy_if.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REPLACE_COPY_IF_H
+#define _LIBCPP___ALGORITHM_REPLACE_COPY_IF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator, class _Predicate, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator replace_copy_if(
+ _InputIterator __first,
+ _InputIterator __last,
+ _OutputIterator __result,
+ _Predicate __pred,
+ const _Tp& __new_value) {
+ for (; __first != __last; ++__first, (void)++__result)
+ if (__pred(*__first))
+ *__result = __new_value;
+ else
+ *__result = *__first;
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_REPLACE_COPY_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/replace_if.h b/libcxx/include/__cxx03/__algorithm/replace_if.h
new file mode 100644
index 00000000000000..78487e3deed709
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/replace_if.h
@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REPLACE_IF_H
+#define _LIBCPP___ALGORITHM_REPLACE_IF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Predicate, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+replace_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, const _Tp& __new_value) {
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ *__first = __new_value;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_REPLACE_IF_H
diff --git a/libcxx/include/__cxx03/__algorithm/reverse.h b/libcxx/include/__cxx03/__algorithm/reverse.h
new file mode 100644
index 00000000000000..4167c9116d96e7
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/reverse.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REVERSE_H
+#define _LIBCPP___ALGORITHM_REVERSE_H
+
+#include <__algorithm/iter_swap.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _BidirectionalIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__reverse_impl(_BidirectionalIterator __first, _BidirectionalIterator __last, bidirectional_iterator_tag) {
+ while (__first != __last) {
+ if (__first == --__last)
+ break;
+ _IterOps<_AlgPolicy>::iter_swap(__first, __last);
+ ++__first;
+ }
+}
+
+template <class _AlgPolicy, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__reverse_impl(_RandomAccessIterator __first, _RandomAccessIterator __last, random_access_iterator_tag) {
+ if (__first != __last)
+ for (; __first < --__last; ++__first)
+ _IterOps<_AlgPolicy>::iter_swap(__first, __last);
+}
+
+template <class _AlgPolicy, class _BidirectionalIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __reverse(_BidirectionalIterator __first, _Sentinel __last) {
+ using _IterCategory = typename _IterOps<_AlgPolicy>::template __iterator_category<_BidirectionalIterator>;
+ std::__reverse_impl<_AlgPolicy>(std::move(__first), std::move(__last), _IterCategory());
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+reverse(_BidirectionalIterator __first, _BidirectionalIterator __last) {
+ std::__reverse<_ClassicAlgPolicy>(std::move(__first), std::move(__last));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_REVERSE_H
diff --git a/libcxx/include/__cxx03/__algorithm/reverse_copy.h b/libcxx/include/__cxx03/__algorithm/reverse_copy.h
new file mode 100644
index 00000000000000..0fcecc39232681
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/reverse_copy.h
@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_REVERSE_COPY_H
+#define _LIBCPP___ALGORITHM_REVERSE_COPY_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _BidirectionalIterator, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+reverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result) {
+ for (; __first != __last; ++__result)
+ *__result = *--__last;
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_REVERSE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/rotate.h b/libcxx/include/__cxx03/__algorithm/rotate.h
new file mode 100644
index 00000000000000..df4ca95aac95bc
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/rotate.h
@@ -0,0 +1,198 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_ROTATE_H
+#define _LIBCPP___ALGORITHM_ROTATE_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/move.h>
+#include <__algorithm/move_backward.h>
+#include <__algorithm/swap_ranges.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_trivially_assignable.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
+__rotate_left(_ForwardIterator __first, _ForwardIterator __last) {
+ typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ value_type __tmp = _Ops::__iter_move(__first);
+ _ForwardIterator __lm1 = std::__move<_AlgPolicy>(_Ops::next(__first), __last, __first).second;
+ *__lm1 = std::move(__tmp);
+ return __lm1;
+}
+
+template <class _AlgPolicy, class _BidirectionalIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _BidirectionalIterator
+__rotate_right(_BidirectionalIterator __first, _BidirectionalIterator __last) {
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ _BidirectionalIterator __lm1 = _Ops::prev(__last);
+ value_type __tmp = _Ops::__iter_move(__lm1);
+ _BidirectionalIterator __fp1 = std::__move_backward<_AlgPolicy>(__first, __lm1, std::move(__last)).second;
+ *__first = std::move(__tmp);
+ return __fp1;
+}
+
+template <class _AlgPolicy, class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 _ForwardIterator
+__rotate_forward(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last) {
+ _ForwardIterator __i = __middle;
+ while (true) {
+ _IterOps<_AlgPolicy>::iter_swap(__first, __i);
+ ++__first;
+ if (++__i == __last)
+ break;
+ if (__first == __middle)
+ __middle = __i;
+ }
+ _ForwardIterator __r = __first;
+ if (__first != __middle) {
+ __i = __middle;
+ while (true) {
+ _IterOps<_AlgPolicy>::iter_swap(__first, __i);
+ ++__first;
+ if (++__i == __last) {
+ if (__first == __middle)
+ break;
+ __i = __middle;
+ } else if (__first == __middle)
+ __middle = __i;
+ }
+ }
+ return __r;
+}
+
+template <typename _Integral>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 _Integral __algo_gcd(_Integral __x, _Integral __y) {
+ do {
+ _Integral __t = __x % __y;
+ __x = __y;
+ __y = __t;
+ } while (__y);
+ return __x;
+}
+
+template <class _AlgPolicy, typename _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 _RandomAccessIterator
+__rotate_gcd(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last) {
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ const difference_type __m1 = __middle - __first;
+ const difference_type __m2 = _Ops::distance(__middle, __last);
+ if (__m1 == __m2) {
+ std::__swap_ranges<_AlgPolicy>(__first, __middle, __middle, __last);
+ return __middle;
+ }
+ const difference_type __g = std::__algo_gcd(__m1, __m2);
+ for (_RandomAccessIterator __p = __first + __g; __p != __first;) {
+ value_type __t(_Ops::__iter_move(--__p));
+ _RandomAccessIterator __p1 = __p;
+ _RandomAccessIterator __p2 = __p1 + __m1;
+ do {
+ *__p1 = _Ops::__iter_move(__p2);
+ __p1 = __p2;
+ const difference_type __d = _Ops::distance(__p2, __last);
+ if (__m1 < __d)
+ __p2 += __m1;
+ else
+ __p2 = __first + (__m1 - __d);
+ } while (__p2 != __p);
+ *__p1 = std::move(__t);
+ }
+ return __first + __m2;
+}
+
+template <class _AlgPolicy, class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
+__rotate_impl(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last, std::forward_iterator_tag) {
+ typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
+ if (is_trivially_move_assignable<value_type>::value) {
+ if (_IterOps<_AlgPolicy>::next(__first) == __middle)
+ return std::__rotate_left<_AlgPolicy>(__first, __last);
+ }
+ return std::__rotate_forward<_AlgPolicy>(__first, __middle, __last);
+}
+
+template <class _AlgPolicy, class _BidirectionalIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _BidirectionalIterator __rotate_impl(
+ _BidirectionalIterator __first,
+ _BidirectionalIterator __middle,
+ _BidirectionalIterator __last,
+ bidirectional_iterator_tag) {
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ if (is_trivially_move_assignable<value_type>::value) {
+ if (_IterOps<_AlgPolicy>::next(__first) == __middle)
+ return std::__rotate_left<_AlgPolicy>(__first, __last);
+ if (_IterOps<_AlgPolicy>::next(__middle) == __last)
+ return std::__rotate_right<_AlgPolicy>(__first, __last);
+ }
+ return std::__rotate_forward<_AlgPolicy>(__first, __middle, __last);
+}
+
+template <class _AlgPolicy, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _RandomAccessIterator __rotate_impl(
+ _RandomAccessIterator __first,
+ _RandomAccessIterator __middle,
+ _RandomAccessIterator __last,
+ random_access_iterator_tag) {
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ if (is_trivially_move_assignable<value_type>::value) {
+ if (_IterOps<_AlgPolicy>::next(__first) == __middle)
+ return std::__rotate_left<_AlgPolicy>(__first, __last);
+ if (_IterOps<_AlgPolicy>::next(__middle) == __last)
+ return std::__rotate_right<_AlgPolicy>(__first, __last);
+ return std::__rotate_gcd<_AlgPolicy>(__first, __middle, __last);
+ }
+ return std::__rotate_forward<_AlgPolicy>(__first, __middle, __last);
+}
+
+template <class _AlgPolicy, class _Iterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iterator, _Iterator>
+__rotate(_Iterator __first, _Iterator __middle, _Sentinel __last) {
+ using _Ret = pair<_Iterator, _Iterator>;
+ _Iterator __last_iter = _IterOps<_AlgPolicy>::next(__middle, __last);
+
+ if (__first == __middle)
+ return _Ret(__last_iter, __last_iter);
+ if (__middle == __last)
+ return _Ret(std::move(__first), std::move(__last_iter));
+
+ using _IterCategory = typename _IterOps<_AlgPolicy>::template __iterator_category<_Iterator>;
+ auto __result = std::__rotate_impl<_AlgPolicy>(std::move(__first), std::move(__middle), __last_iter, _IterCategory());
+
+ return _Ret(std::move(__result), std::move(__last_iter));
+}
+
+template <class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+rotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last) {
+ return std::__rotate<_ClassicAlgPolicy>(std::move(__first), std::move(__middle), std::move(__last)).first;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_ROTATE_H
diff --git a/libcxx/include/__cxx03/__algorithm/rotate_copy.h b/libcxx/include/__cxx03/__algorithm/rotate_copy.h
new file mode 100644
index 00000000000000..cddcadd237d902
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/rotate_copy.h
@@ -0,0 +1,29 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_ROTATE_COPY_H
+#define _LIBCPP___ALGORITHM_ROTATE_COPY_H
+
+#include <__algorithm/copy.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+rotate_copy(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last, _OutputIterator __result) {
+ return std::copy(__first, __middle, std::copy(__middle, __last, __result));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_ROTATE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/sample.h b/libcxx/include/__cxx03/__algorithm/sample.h
new file mode 100644
index 00000000000000..ebe5180b7eeca6
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/sample.h
@@ -0,0 +1,123 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SAMPLE_H
+#define _LIBCPP___ALGORITHM_SAMPLE_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__random/uniform_int_distribution.h>
+#include <__type_traits/common_type.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy,
+ class _PopulationIterator,
+ class _PopulationSentinel,
+ class _SampleIterator,
+ class _Distance,
+ class _UniformRandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI _SampleIterator __sample(
+ _PopulationIterator __first,
+ _PopulationSentinel __last,
+ _SampleIterator __output_iter,
+ _Distance __n,
+ _UniformRandomNumberGenerator& __g,
+ input_iterator_tag) {
+ _Distance __k = 0;
+ for (; __first != __last && __k < __n; ++__first, (void)++__k)
+ __output_iter[__k] = *__first;
+ _Distance __sz = __k;
+ for (; __first != __last; ++__first, (void)++__k) {
+ _Distance __r = uniform_int_distribution<_Distance>(0, __k)(__g);
+ if (__r < __sz)
+ __output_iter[__r] = *__first;
+ }
+ return __output_iter + std::min(__n, __k);
+}
+
+template <class _AlgPolicy,
+ class _PopulationIterator,
+ class _PopulationSentinel,
+ class _SampleIterator,
+ class _Distance,
+ class _UniformRandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI _SampleIterator __sample(
+ _PopulationIterator __first,
+ _PopulationSentinel __last,
+ _SampleIterator __output_iter,
+ _Distance __n,
+ _UniformRandomNumberGenerator& __g,
+ forward_iterator_tag) {
+ _Distance __unsampled_sz = _IterOps<_AlgPolicy>::distance(__first, __last);
+ for (__n = std::min(__n, __unsampled_sz); __n != 0; ++__first) {
+ _Distance __r = uniform_int_distribution<_Distance>(0, --__unsampled_sz)(__g);
+ if (__r < __n) {
+ *__output_iter++ = *__first;
+ --__n;
+ }
+ }
+ return __output_iter;
+}
+
+template <class _AlgPolicy,
+ class _PopulationIterator,
+ class _PopulationSentinel,
+ class _SampleIterator,
+ class _Distance,
+ class _UniformRandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI _SampleIterator __sample(
+ _PopulationIterator __first,
+ _PopulationSentinel __last,
+ _SampleIterator __output_iter,
+ _Distance __n,
+ _UniformRandomNumberGenerator& __g) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n >= 0, "N must be a positive number.");
+
+ using _PopIterCategory = typename _IterOps<_AlgPolicy>::template __iterator_category<_PopulationIterator>;
+ using _Difference = typename _IterOps<_AlgPolicy>::template __difference_type<_PopulationIterator>;
+ using _CommonType = typename common_type<_Distance, _Difference>::type;
+
+ return std::__sample<_AlgPolicy>(
+ std::move(__first), std::move(__last), std::move(__output_iter), _CommonType(__n), __g, _PopIterCategory());
+}
+
+#if _LIBCPP_STD_VER >= 17
+template <class _PopulationIterator, class _SampleIterator, class _Distance, class _UniformRandomNumberGenerator>
+inline _LIBCPP_HIDE_FROM_ABI _SampleIterator
+sample(_PopulationIterator __first,
+ _PopulationIterator __last,
+ _SampleIterator __output_iter,
+ _Distance __n,
+ _UniformRandomNumberGenerator&& __g) {
+ static_assert(__has_forward_iterator_category<_PopulationIterator>::value ||
+ __has_random_access_iterator_category<_SampleIterator>::value,
+ "SampleIterator must meet the requirements of RandomAccessIterator");
+
+ return std::__sample<_ClassicAlgPolicy>(std::move(__first), std::move(__last), std::move(__output_iter), __n, __g);
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SAMPLE_H
diff --git a/libcxx/include/__cxx03/__algorithm/search.h b/libcxx/include/__cxx03/__algorithm/search.h
new file mode 100644
index 00000000000000..b82ca780953541
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/search.h
@@ -0,0 +1,192 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SEARCH_H
+#define _LIBCPP___ALGORITHM_SEARCH_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_callable.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Pred,
+ class _Proj1,
+ class _Proj2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter1, _Iter1> __search_forward_impl(
+ _Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Sent2 __last2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ if (__first2 == __last2)
+ return std::make_pair(__first1, __first1); // Everything matches an empty sequence
+ while (true) {
+ // Find first element in sequence 1 that matchs *__first2, with a mininum of loop checks
+ while (true) {
+ if (__first1 == __last1) { // return __last1 if no element matches *__first2
+ _IterOps<_AlgPolicy>::__advance_to(__first1, __last1);
+ return std::make_pair(__first1, __first1);
+ }
+ if (std::__invoke(__pred, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ break;
+ ++__first1;
+ }
+ // *__first1 matches *__first2, now match elements after here
+ _Iter1 __m1 = __first1;
+ _Iter2 __m2 = __first2;
+ while (true) {
+ if (++__m2 == __last2) // If pattern exhausted, __first1 is the answer (works for 1 element pattern)
+ return std::make_pair(__first1, ++__m1);
+ if (++__m1 == __last1) { // Otherwise if source exhaused, pattern not found
+ return std::make_pair(__m1, __m1);
+ }
+
+ // if there is a mismatch, restart with a new __first1
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *__m1), std::__invoke(__proj2, *__m2))) {
+ ++__first1;
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _AlgPolicy,
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Pred,
+ class _Proj1,
+ class _Proj2,
+ class _DiffT1,
+ class _DiffT2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter1, _Iter1> __search_random_access_impl(
+ _Iter1 __first1,
+ _Sent1 __last1,
+ _Iter2 __first2,
+ _Sent2 __last2,
+ _Pred& __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2,
+ _DiffT1 __size1,
+ _DiffT2 __size2) {
+ const _Iter1 __s = __first1 + __size1 - _DiffT1(__size2 - 1); // Start of pattern match can't go beyond here
+
+ while (true) {
+ while (true) {
+ if (__first1 == __s) {
+ _IterOps<_AlgPolicy>::__advance_to(__first1, __last1);
+ return std::make_pair(__first1, __first1);
+ }
+ if (std::__invoke(__pred, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ break;
+ ++__first1;
+ }
+
+ _Iter1 __m1 = __first1;
+ _Iter2 __m2 = __first2;
+ while (true) {
+ if (++__m2 == __last2)
+ return std::make_pair(__first1, __first1 + _DiffT1(__size2));
+ ++__m1; // no need to check range on __m1 because __s guarantees we have enough source
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *__m1), std::__invoke(__proj2, *__m2))) {
+ ++__first1;
+ break;
+ }
+ }
+ }
+}
+
+template <class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Pred,
+ class _Proj1,
+ class _Proj2,
+ __enable_if_t<__has_random_access_iterator_category<_Iter1>::value &&
+ __has_random_access_iterator_category<_Iter2>::value,
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter1, _Iter1> __search_impl(
+ _Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Sent2 __last2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ auto __size2 = __last2 - __first2;
+ if (__size2 == 0)
+ return std::make_pair(__first1, __first1);
+
+ auto __size1 = __last1 - __first1;
+ if (__size1 < __size2) {
+ return std::make_pair(__last1, __last1);
+ }
+
+ return std::__search_random_access_impl<_ClassicAlgPolicy>(
+ __first1, __last1, __first2, __last2, __pred, __proj1, __proj2, __size1, __size2);
+}
+
+template <
+ class _Iter1,
+ class _Sent1,
+ class _Iter2,
+ class _Sent2,
+ class _Pred,
+ class _Proj1,
+ class _Proj2,
+ __enable_if_t<__has_forward_iterator_category<_Iter1>::value && __has_forward_iterator_category<_Iter2>::value &&
+ !(__has_random_access_iterator_category<_Iter1>::value &&
+ __has_random_access_iterator_category<_Iter2>::value),
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter1, _Iter1> __search_impl(
+ _Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Sent2 __last2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ return std::__search_forward_impl<_ClassicAlgPolicy>(__first1, __last1, __first2, __last2, __pred, __proj1, __proj2);
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator1
+search(_ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _BinaryPredicate __pred) {
+ static_assert(__is_callable<_BinaryPredicate, decltype(*__first1), decltype(*__first2)>::value,
+ "BinaryPredicate has to be callable");
+ auto __proj = __identity();
+ return std::__search_impl(__first1, __last1, __first2, __last2, __pred, __proj, __proj).first;
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator1
+search(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2, _ForwardIterator2 __last2) {
+ return std::search(__first1, __last1, __first2, __last2, __equal_to());
+}
+
+#if _LIBCPP_STD_VER >= 17
+template <class _ForwardIterator, class _Searcher>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+search(_ForwardIterator __f, _ForwardIterator __l, const _Searcher& __s) {
+ return __s(__f, __l).first;
+}
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_SEARCH_H
diff --git a/libcxx/include/__cxx03/__algorithm/search_n.h b/libcxx/include/__cxx03/__algorithm/search_n.h
new file mode 100644
index 00000000000000..771647d3168a43
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/search_n.h
@@ -0,0 +1,155 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SEARCH_N_H
+#define _LIBCPP___ALGORITHM_SEARCH_N_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/is_callable.h>
+#include <__utility/convert_to_integral.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Pred, class _Iter, class _Sent, class _SizeT, class _Type, class _Proj>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter, _Iter> __search_n_forward_impl(
+ _Iter __first, _Sent __last, _SizeT __count, const _Type& __value, _Pred& __pred, _Proj& __proj) {
+ if (__count <= 0)
+ return std::make_pair(__first, __first);
+ while (true) {
+ // Find first element in sequence that matchs __value, with a mininum of loop checks
+ while (true) {
+ if (__first == __last) { // return __last if no element matches __value
+ _IterOps<_AlgPolicy>::__advance_to(__first, __last);
+ return std::make_pair(__first, __first);
+ }
+ if (std::__invoke(__pred, std::__invoke(__proj, *__first), __value))
+ break;
+ ++__first;
+ }
+ // *__first matches __value, now match elements after here
+ _Iter __m = __first;
+ _SizeT __c(0);
+ while (true) {
+ if (++__c == __count) // If pattern exhausted, __first is the answer (works for 1 element pattern)
+ return std::make_pair(__first, ++__m);
+ if (++__m == __last) { // Otherwise if source exhaused, pattern not found
+ _IterOps<_AlgPolicy>::__advance_to(__first, __last);
+ return std::make_pair(__first, __first);
+ }
+
+ // if there is a mismatch, restart with a new __first
+ if (!std::__invoke(__pred, std::__invoke(__proj, *__m), __value)) {
+ __first = __m;
+ ++__first;
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _AlgPolicy, class _Pred, class _Iter, class _Sent, class _SizeT, class _Type, class _Proj, class _DiffT>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 std::pair<_Iter, _Iter> __search_n_random_access_impl(
+ _Iter __first, _Sent __last, _SizeT __count, const _Type& __value, _Pred& __pred, _Proj& __proj, _DiffT __size1) {
+ using difference_type = typename iterator_traits<_Iter>::difference_type;
+ if (__count == 0)
+ return std::make_pair(__first, __first);
+ if (__size1 < static_cast<_DiffT>(__count)) {
+ _IterOps<_AlgPolicy>::__advance_to(__first, __last);
+ return std::make_pair(__first, __first);
+ }
+
+ const auto __s = __first + __size1 - difference_type(__count - 1); // Start of pattern match can't go beyond here
+ while (true) {
+ // Find first element in sequence that matchs __value, with a mininum of loop checks
+ while (true) {
+ if (__first >= __s) { // return __last if no element matches __value
+ _IterOps<_AlgPolicy>::__advance_to(__first, __last);
+ return std::make_pair(__first, __first);
+ }
+ if (std::__invoke(__pred, std::__invoke(__proj, *__first), __value))
+ break;
+ ++__first;
+ }
+ // *__first matches __value_, now match elements after here
+ auto __m = __first;
+ _SizeT __c(0);
+ while (true) {
+ if (++__c == __count) // If pattern exhausted, __first is the answer (works for 1 element pattern)
+ return std::make_pair(__first, __first + _DiffT(__count));
+ ++__m; // no need to check range on __m because __s guarantees we have enough source
+
+ // if there is a mismatch, restart with a new __first
+ if (!std::__invoke(__pred, std::__invoke(__proj, *__m), __value)) {
+ __first = __m;
+ ++__first;
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _Iter,
+ class _Sent,
+ class _DiffT,
+ class _Type,
+ class _Pred,
+ class _Proj,
+ __enable_if_t<__has_random_access_iterator_category<_Iter>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter, _Iter>
+__search_n_impl(_Iter __first, _Sent __last, _DiffT __count, const _Type& __value, _Pred& __pred, _Proj& __proj) {
+ return std::__search_n_random_access_impl<_ClassicAlgPolicy>(
+ __first, __last, __count, __value, __pred, __proj, __last - __first);
+}
+
+template <class _Iter1,
+ class _Sent1,
+ class _DiffT,
+ class _Type,
+ class _Pred,
+ class _Proj,
+ __enable_if_t<__has_forward_iterator_category<_Iter1>::value &&
+ !__has_random_access_iterator_category<_Iter1>::value,
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Iter1, _Iter1>
+__search_n_impl(_Iter1 __first, _Sent1 __last, _DiffT __count, const _Type& __value, _Pred& __pred, _Proj& __proj) {
+ return std::__search_n_forward_impl<_ClassicAlgPolicy>(__first, __last, __count, __value, __pred, __proj);
+}
+
+template <class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator search_n(
+ _ForwardIterator __first, _ForwardIterator __last, _Size __count, const _Tp& __value, _BinaryPredicate __pred) {
+ static_assert(
+ __is_callable<_BinaryPredicate, decltype(*__first), const _Tp&>::value, "BinaryPredicate has to be callable");
+ auto __proj = __identity();
+ return std::__search_n_impl(__first, __last, std::__convert_to_integral(__count), __value, __pred, __proj).first;
+}
+
+template <class _ForwardIterator, class _Size, class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+search_n(_ForwardIterator __first, _ForwardIterator __last, _Size __count, const _Tp& __value) {
+ return std::search_n(__first, __last, std::__convert_to_integral(__count), __value, __equal_to());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_SEARCH_N_H
diff --git a/libcxx/include/__cxx03/__algorithm/set_difference.h b/libcxx/include/__cxx03/__algorithm/set_difference.h
new file mode 100644
index 00000000000000..f414bcecb50df1
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/set_difference.h
@@ -0,0 +1,79 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SET_DIFFERENCE_H
+#define _LIBCPP___ALGORITHM_SET_DIFFERENCE_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/copy.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Comp, class _InIter1, class _Sent1, class _InIter2, class _Sent2, class _OutIter>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<__remove_cvref_t<_InIter1>, __remove_cvref_t<_OutIter> >
+__set_difference(
+ _InIter1&& __first1, _Sent1&& __last1, _InIter2&& __first2, _Sent2&& __last2, _OutIter&& __result, _Comp&& __comp) {
+ while (__first1 != __last1 && __first2 != __last2) {
+ if (__comp(*__first1, *__first2)) {
+ *__result = *__first1;
+ ++__first1;
+ ++__result;
+ } else if (__comp(*__first2, *__first1)) {
+ ++__first2;
+ } else {
+ ++__first1;
+ ++__first2;
+ }
+ }
+ return std::__copy<_AlgPolicy>(std::move(__first1), std::move(__last1), std::move(__result));
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_difference(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result,
+ _Compare __comp) {
+ return std::__set_difference<_ClassicAlgPolicy, __comp_ref_type<_Compare> >(
+ __first1, __last1, __first2, __last2, __result, __comp)
+ .second;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_difference(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result) {
+ return std::__set_difference<_ClassicAlgPolicy>(__first1, __last1, __first2, __last2, __result, __less<>()).second;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SET_DIFFERENCE_H
diff --git a/libcxx/include/__cxx03/__algorithm/set_intersection.h b/libcxx/include/__cxx03/__algorithm/set_intersection.h
new file mode 100644
index 00000000000000..bb0d86cd0f58d2
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/set_intersection.h
@@ -0,0 +1,217 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SET_INTERSECTION_H
+#define _LIBCPP___ALGORITHM_SET_INTERSECTION_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/lower_bound.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__type_traits/is_same.h>
+#include <__utility/exchange.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InIter1, class _InIter2, class _OutIter>
+struct __set_intersection_result {
+ _InIter1 __in1_;
+ _InIter2 __in2_;
+ _OutIter __out_;
+
+ // need a constructor as C++03 aggregate init is hard
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ __set_intersection_result(_InIter1&& __in_iter1, _InIter2&& __in_iter2, _OutIter&& __out_iter)
+ : __in1_(std::move(__in_iter1)), __in2_(std::move(__in_iter2)), __out_(std::move(__out_iter)) {}
+};
+
+// Helper for __set_intersection() with one-sided binary search: populate result and advance input iterators if they
+// are found to potentially contain the same value in two consecutive calls. This function is very intimately related to
+// the way it is used and doesn't attempt to abstract that, it's not appropriate for general usage outside of its
+// context.
+template <class _InForwardIter1, class _InForwardIter2, class _OutIter>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __set_intersection_add_output_if_equal(
+ bool __may_be_equal,
+ _InForwardIter1& __first1,
+ _InForwardIter2& __first2,
+ _OutIter& __result,
+ bool& __prev_may_be_equal) {
+ if (__may_be_equal && __prev_may_be_equal) {
+ *__result = *__first1;
+ ++__result;
+ ++__first1;
+ ++__first2;
+ __prev_may_be_equal = false;
+ } else {
+ __prev_may_be_equal = __may_be_equal;
+ }
+}
+
+// With forward iterators we can make multiple passes over the data, allowing the use of one-sided binary search to
+// reduce best-case complexity to log(N). Understanding how we can use binary search and still respect complexity
+// guarantees is _not_ straightforward: the guarantee is "at most 2*(N+M)-1 comparisons", and one-sided binary search
+// will necessarily overshoot depending on the position of the needle in the haystack -- for instance, if we're
+// searching for 3 in (1, 2, 3, 4), we'll check if 3<1, then 3<2, then 3<4, and, finally, 3<3, for a total of 4
+// comparisons, when linear search would have yielded 3. However, because we won't need to perform the intervening
+// reciprocal comparisons (ie 1<3, 2<3, 4<3), that extra comparison doesn't run afoul of the guarantee. Additionally,
+// this type of scenario can only happen for match distances of up to 5 elements, because 2*log2(8) is 6, and we'll
+// still be worse-off at position 5 of an 8-element set. From then onwards these scenarios can't happen. TL;DR: we'll be
+// 1 comparison worse-off compared to the classic linear-searching algorithm if matching position 3 of a set with 4
+// elements, or position 5 if the set has 7 or 8 elements, but we'll never exceed the complexity guarantees from the
+// standard.
+template <class _AlgPolicy,
+ class _Compare,
+ class _InForwardIter1,
+ class _Sent1,
+ class _InForwardIter2,
+ class _Sent2,
+ class _OutIter>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX20 __set_intersection_result<_InForwardIter1, _InForwardIter2, _OutIter>
+__set_intersection(
+ _InForwardIter1 __first1,
+ _Sent1 __last1,
+ _InForwardIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Compare&& __comp,
+ std::forward_iterator_tag,
+ std::forward_iterator_tag) {
+ _LIBCPP_CONSTEXPR std::__identity __proj;
+ bool __prev_may_be_equal = false;
+
+ while (__first2 != __last2) {
+ _InForwardIter1 __first1_next =
+ std::__lower_bound_onesided<_AlgPolicy>(__first1, __last1, *__first2, __comp, __proj);
+ std::swap(__first1_next, __first1);
+ // keeping in mind that a==b iff !(a<b) && !(b<a):
+ // if we can't advance __first1, that means !(*__first1 < *_first2), therefore __may_be_equal==true
+ std::__set_intersection_add_output_if_equal(
+ __first1 == __first1_next, __first1, __first2, __result, __prev_may_be_equal);
+ if (__first1 == __last1)
+ break;
+
+ _InForwardIter2 __first2_next =
+ std::__lower_bound_onesided<_AlgPolicy>(__first2, __last2, *__first1, __comp, __proj);
+ std::swap(__first2_next, __first2);
+ std::__set_intersection_add_output_if_equal(
+ __first2 == __first2_next, __first1, __first2, __result, __prev_may_be_equal);
+ }
+ return __set_intersection_result<_InForwardIter1, _InForwardIter2, _OutIter>(
+ _IterOps<_AlgPolicy>::next(std::move(__first1), std::move(__last1)),
+ _IterOps<_AlgPolicy>::next(std::move(__first2), std::move(__last2)),
+ std::move(__result));
+}
+
+// input iterators are not suitable for multipass algorithms, so we stick to the classic single-pass version
+template <class _AlgPolicy,
+ class _Compare,
+ class _InInputIter1,
+ class _Sent1,
+ class _InInputIter2,
+ class _Sent2,
+ class _OutIter>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX20 __set_intersection_result<_InInputIter1, _InInputIter2, _OutIter>
+__set_intersection(
+ _InInputIter1 __first1,
+ _Sent1 __last1,
+ _InInputIter2 __first2,
+ _Sent2 __last2,
+ _OutIter __result,
+ _Compare&& __comp,
+ std::input_iterator_tag,
+ std::input_iterator_tag) {
+ while (__first1 != __last1 && __first2 != __last2) {
+ if (__comp(*__first1, *__first2))
+ ++__first1;
+ else {
+ if (!__comp(*__first2, *__first1)) {
+ *__result = *__first1;
+ ++__result;
+ ++__first1;
+ }
+ ++__first2;
+ }
+ }
+
+ return __set_intersection_result<_InInputIter1, _InInputIter2, _OutIter>(
+ _IterOps<_AlgPolicy>::next(std::move(__first1), std::move(__last1)),
+ _IterOps<_AlgPolicy>::next(std::move(__first2), std::move(__last2)),
+ std::move(__result));
+}
+
+template <class _AlgPolicy, class _Compare, class _InIter1, class _Sent1, class _InIter2, class _Sent2, class _OutIter>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX20 __set_intersection_result<_InIter1, _InIter2, _OutIter>
+__set_intersection(
+ _InIter1 __first1, _Sent1 __last1, _InIter2 __first2, _Sent2 __last2, _OutIter __result, _Compare&& __comp) {
+ return std::__set_intersection<_AlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ std::forward<_Compare>(__comp),
+ typename std::_IterOps<_AlgPolicy>::template __iterator_category<_InIter1>(),
+ typename std::_IterOps<_AlgPolicy>::template __iterator_category<_InIter2>());
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_intersection(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result,
+ _Compare __comp) {
+ return std::__set_intersection<_ClassicAlgPolicy, __comp_ref_type<_Compare> >(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ __comp)
+ .__out_;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_intersection(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result) {
+ return std::__set_intersection<_ClassicAlgPolicy>(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ __less<>())
+ .__out_;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SET_INTERSECTION_H
diff --git a/libcxx/include/__cxx03/__algorithm/set_symmetric_difference.h b/libcxx/include/__cxx03/__algorithm/set_symmetric_difference.h
new file mode 100644
index 00000000000000..db36665a61365c
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/set_symmetric_difference.h
@@ -0,0 +1,109 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SET_SYMMETRIC_DIFFERENCE_H
+#define _LIBCPP___ALGORITHM_SET_SYMMETRIC_DIFFERENCE_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/copy.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InIter1, class _InIter2, class _OutIter>
+struct __set_symmetric_difference_result {
+ _InIter1 __in1_;
+ _InIter2 __in2_;
+ _OutIter __out_;
+
+ // need a constructor as C++03 aggregate init is hard
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ __set_symmetric_difference_result(_InIter1&& __in_iter1, _InIter2&& __in_iter2, _OutIter&& __out_iter)
+ : __in1_(std::move(__in_iter1)), __in2_(std::move(__in_iter2)), __out_(std::move(__out_iter)) {}
+};
+
+template <class _AlgPolicy, class _Compare, class _InIter1, class _Sent1, class _InIter2, class _Sent2, class _OutIter>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __set_symmetric_difference_result<_InIter1, _InIter2, _OutIter>
+__set_symmetric_difference(
+ _InIter1 __first1, _Sent1 __last1, _InIter2 __first2, _Sent2 __last2, _OutIter __result, _Compare&& __comp) {
+ while (__first1 != __last1) {
+ if (__first2 == __last2) {
+ auto __ret1 = std::__copy<_AlgPolicy>(std::move(__first1), std::move(__last1), std::move(__result));
+ return __set_symmetric_difference_result<_InIter1, _InIter2, _OutIter>(
+ std::move(__ret1.first), std::move(__first2), std::move((__ret1.second)));
+ }
+ if (__comp(*__first1, *__first2)) {
+ *__result = *__first1;
+ ++__result;
+ ++__first1;
+ } else {
+ if (__comp(*__first2, *__first1)) {
+ *__result = *__first2;
+ ++__result;
+ } else {
+ ++__first1;
+ }
+ ++__first2;
+ }
+ }
+ auto __ret2 = std::__copy<_AlgPolicy>(std::move(__first2), std::move(__last2), std::move(__result));
+ return __set_symmetric_difference_result<_InIter1, _InIter2, _OutIter>(
+ std::move(__first1), std::move(__ret2.first), std::move((__ret2.second)));
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_symmetric_difference(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result,
+ _Compare __comp) {
+ return std::__set_symmetric_difference<_ClassicAlgPolicy, __comp_ref_type<_Compare> >(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ __comp)
+ .__out_;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_symmetric_difference(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result) {
+ return std::set_symmetric_difference(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SET_SYMMETRIC_DIFFERENCE_H
diff --git a/libcxx/include/__cxx03/__algorithm/set_union.h b/libcxx/include/__cxx03/__algorithm/set_union.h
new file mode 100644
index 00000000000000..a79c50fd3cf2f0
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/set_union.h
@@ -0,0 +1,105 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SET_UNION_H
+#define _LIBCPP___ALGORITHM_SET_UNION_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/copy.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InIter1, class _InIter2, class _OutIter>
+struct __set_union_result {
+ _InIter1 __in1_;
+ _InIter2 __in2_;
+ _OutIter __out_;
+
+ // need a constructor as C++03 aggregate init is hard
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ __set_union_result(_InIter1&& __in_iter1, _InIter2&& __in_iter2, _OutIter&& __out_iter)
+ : __in1_(std::move(__in_iter1)), __in2_(std::move(__in_iter2)), __out_(std::move(__out_iter)) {}
+};
+
+template <class _AlgPolicy, class _Compare, class _InIter1, class _Sent1, class _InIter2, class _Sent2, class _OutIter>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __set_union_result<_InIter1, _InIter2, _OutIter> __set_union(
+ _InIter1 __first1, _Sent1 __last1, _InIter2 __first2, _Sent2 __last2, _OutIter __result, _Compare&& __comp) {
+ for (; __first1 != __last1; ++__result) {
+ if (__first2 == __last2) {
+ auto __ret1 = std::__copy<_AlgPolicy>(std::move(__first1), std::move(__last1), std::move(__result));
+ return __set_union_result<_InIter1, _InIter2, _OutIter>(
+ std::move(__ret1.first), std::move(__first2), std::move((__ret1.second)));
+ }
+ if (__comp(*__first2, *__first1)) {
+ *__result = *__first2;
+ ++__first2;
+ } else {
+ if (!__comp(*__first1, *__first2)) {
+ ++__first2;
+ }
+ *__result = *__first1;
+ ++__first1;
+ }
+ }
+ auto __ret2 = std::__copy<_AlgPolicy>(std::move(__first2), std::move(__last2), std::move(__result));
+ return __set_union_result<_InIter1, _InIter2, _OutIter>(
+ std::move(__first1), std::move(__ret2.first), std::move((__ret2.second)));
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_union(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result,
+ _Compare __comp) {
+ return std::__set_union<_ClassicAlgPolicy, __comp_ref_type<_Compare> >(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ __comp)
+ .__out_;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_union(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result) {
+ return std::set_union(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__result),
+ __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SET_UNION_H
diff --git a/libcxx/include/__cxx03/__algorithm/shift_left.h b/libcxx/include/__cxx03/__algorithm/shift_left.h
new file mode 100644
index 00000000000000..06cd7c5f87644e
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/shift_left.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SHIFT_LEFT_H
+#define _LIBCPP___ALGORITHM_SHIFT_LEFT_H
+
+#include <__algorithm/move.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _ForwardIterator
+shift_left(_ForwardIterator __first,
+ _ForwardIterator __last,
+ typename iterator_traits<_ForwardIterator>::difference_type __n) {
+ if (__n == 0) {
+ return __last;
+ }
+
+ _ForwardIterator __m = __first;
+ if constexpr (__has_random_access_iterator_category<_ForwardIterator>::value) {
+ if (__n >= __last - __first) {
+ return __first;
+ }
+ __m += __n;
+ } else {
+ for (; __n > 0; --__n) {
+ if (__m == __last) {
+ return __first;
+ }
+ ++__m;
+ }
+ }
+ return std::move(__m, __last, __first);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SHIFT_LEFT_H
diff --git a/libcxx/include/__cxx03/__algorithm/shift_right.h b/libcxx/include/__cxx03/__algorithm/shift_right.h
new file mode 100644
index 00000000000000..01853057fc4788
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/shift_right.h
@@ -0,0 +1,105 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SHIFT_RIGHT_H
+#define _LIBCPP___ALGORITHM_SHIFT_RIGHT_H
+
+#include <__algorithm/move.h>
+#include <__algorithm/move_backward.h>
+#include <__algorithm/swap_ranges.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/swap.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _ForwardIterator
+shift_right(_ForwardIterator __first,
+ _ForwardIterator __last,
+ typename iterator_traits<_ForwardIterator>::difference_type __n) {
+ if (__n == 0) {
+ return __first;
+ }
+
+ if constexpr (__has_random_access_iterator_category<_ForwardIterator>::value) {
+ decltype(__n) __d = __last - __first;
+ if (__n >= __d) {
+ return __last;
+ }
+ _ForwardIterator __m = __first + (__d - __n);
+ return std::move_backward(__first, __m, __last);
+ } else if constexpr (__has_bidirectional_iterator_category<_ForwardIterator>::value) {
+ _ForwardIterator __m = __last;
+ for (; __n > 0; --__n) {
+ if (__m == __first) {
+ return __last;
+ }
+ --__m;
+ }
+ return std::move_backward(__first, __m, __last);
+ } else {
+ _ForwardIterator __ret = __first;
+ for (; __n > 0; --__n) {
+ if (__ret == __last) {
+ return __last;
+ }
+ ++__ret;
+ }
+
+ // We have an __n-element scratch space from __first to __ret.
+ // Slide an __n-element window [__trail, __lead) from left to right.
+ // We're essentially doing swap_ranges(__first, __ret, __trail, __lead)
+ // over and over; but once __lead reaches __last we needn't bother
+ // to save the values of elements [__trail, __last).
+
+ auto __trail = __first;
+ auto __lead = __ret;
+ while (__trail != __ret) {
+ if (__lead == __last) {
+ std::move(__first, __trail, __ret);
+ return __ret;
+ }
+ ++__trail;
+ ++__lead;
+ }
+
+ _ForwardIterator __mid = __first;
+ while (true) {
+ if (__lead == __last) {
+ __trail = std::move(__mid, __ret, __trail);
+ std::move(__first, __mid, __trail);
+ return __ret;
+ }
+ swap(*__mid, *__trail);
+ ++__mid;
+ ++__trail;
+ ++__lead;
+ if (__mid == __ret) {
+ __mid = __first;
+ }
+ }
+ }
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SHIFT_RIGHT_H
diff --git a/libcxx/include/__cxx03/__algorithm/shuffle.h b/libcxx/include/__cxx03/__algorithm/shuffle.h
new file mode 100644
index 00000000000000..c9c56ce8c2c0b1
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/shuffle.h
@@ -0,0 +1,167 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SHUFFLE_H
+#define _LIBCPP___ALGORITHM_SHUFFLE_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__random/uniform_int_distribution.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_EXPORTED_FROM_ABI __libcpp_debug_randomizer {
+public:
+ _LIBCPP_HIDE_FROM_ABI __libcpp_debug_randomizer() {
+ __state_ = __seed();
+ __inc_ = __state_ + 0xda3e39cb94b95bdbULL;
+ __inc_ = (__inc_ << 1) | 1;
+ }
+ typedef uint_fast32_t result_type;
+
+ static const result_type _Min = 0;
+ static const result_type _Max = 0xFFFFFFFF;
+
+ _LIBCPP_HIDE_FROM_ABI result_type operator()() {
+ uint_fast64_t __oldstate = __state_;
+ __state_ = __oldstate * 6364136223846793005ULL + __inc_;
+ return __oldstate >> 32;
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+
+private:
+ uint_fast64_t __state_;
+ uint_fast64_t __inc_;
+ _LIBCPP_HIDE_FROM_ABI static uint_fast64_t __seed() {
+#ifdef _LIBCPP_DEBUG_RANDOMIZE_UNSPECIFIED_STABILITY_SEED
+ return _LIBCPP_DEBUG_RANDOMIZE_UNSPECIFIED_STABILITY_SEED;
+#else
+ static char __x;
+ return reinterpret_cast<uintptr_t>(&__x);
+#endif
+ }
+};
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE) || defined(_LIBCPP_BUILDING_LIBRARY)
+class _LIBCPP_EXPORTED_FROM_ABI __rs_default;
+
+_LIBCPP_EXPORTED_FROM_ABI __rs_default __rs_get();
+
+class _LIBCPP_EXPORTED_FROM_ABI __rs_default {
+ static unsigned __c_;
+
+ __rs_default();
+
+public:
+ typedef uint_fast32_t result_type;
+
+ static const result_type _Min = 0;
+ static const result_type _Max = 0xFFFFFFFF;
+
+ __rs_default(const __rs_default&);
+ ~__rs_default();
+
+ result_type operator()();
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+
+ friend _LIBCPP_EXPORTED_FROM_ABI __rs_default __rs_get();
+};
+
+_LIBCPP_EXPORTED_FROM_ABI __rs_default __rs_get();
+
+template <class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_DEPRECATED_IN_CXX14 void
+random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef uniform_int_distribution<ptrdiff_t> _Dp;
+ typedef typename _Dp::param_type _Pp;
+ difference_type __d = __last - __first;
+ if (__d > 1) {
+ _Dp __uid;
+ __rs_default __g = __rs_get();
+ for (--__last, (void)--__d; __first < __last; ++__first, (void)--__d) {
+ difference_type __i = __uid(__g, _Pp(0, __d));
+ if (__i != difference_type(0))
+ swap(*__first, *(__first + __i));
+ }
+ }
+}
+
+template <class _RandomAccessIterator, class _RandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_DEPRECATED_IN_CXX14 void
+random_shuffle(_RandomAccessIterator __first,
+ _RandomAccessIterator __last,
+# ifndef _LIBCPP_CXX03_LANG
+ _RandomNumberGenerator&& __rand)
+# else
+ _RandomNumberGenerator& __rand)
+# endif
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ difference_type __d = __last - __first;
+ if (__d > 1) {
+ for (--__last; __first < __last; ++__first, (void)--__d) {
+ difference_type __i = __rand(__d);
+ if (__i != difference_type(0))
+ swap(*__first, *(__first + __i));
+ }
+ }
+}
+#endif
+
+template <class _AlgPolicy, class _RandomAccessIterator, class _Sentinel, class _UniformRandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI _RandomAccessIterator
+__shuffle(_RandomAccessIterator __first, _Sentinel __last_sentinel, _UniformRandomNumberGenerator&& __g) {
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef uniform_int_distribution<ptrdiff_t> _Dp;
+ typedef typename _Dp::param_type _Pp;
+
+ auto __original_last = _IterOps<_AlgPolicy>::next(__first, __last_sentinel);
+ auto __last = __original_last;
+ difference_type __d = __last - __first;
+ if (__d > 1) {
+ _Dp __uid;
+ for (--__last, (void)--__d; __first < __last; ++__first, (void)--__d) {
+ difference_type __i = __uid(__g, _Pp(0, __d));
+ if (__i != difference_type(0))
+ _IterOps<_AlgPolicy>::iter_swap(__first, __first + __i);
+ }
+ }
+
+ return __original_last;
+}
+
+template <class _RandomAccessIterator, class _UniformRandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI void
+shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last, _UniformRandomNumberGenerator&& __g) {
+ (void)std::__shuffle<_ClassicAlgPolicy>(
+ std::move(__first), std::move(__last), std::forward<_UniformRandomNumberGenerator>(__g));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SHUFFLE_H
diff --git a/libcxx/include/__cxx03/__algorithm/sift_down.h b/libcxx/include/__cxx03/__algorithm/sift_down.h
new file mode 100644
index 00000000000000..42803e30631fb1
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/sift_down.h
@@ -0,0 +1,118 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SIFT_DOWN_H
+#define _LIBCPP___ALGORITHM_SIFT_DOWN_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__sift_down(_RandomAccessIterator __first,
+ _Compare&& __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len,
+ _RandomAccessIterator __start) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ // left-child of __start is at 2 * __start + 1
+ // right-child of __start is at 2 * __start + 2
+ difference_type __child = __start - __first;
+
+ if (__len < 2 || (__len - 2) / 2 < __child)
+ return;
+
+ __child = 2 * __child + 1;
+ _RandomAccessIterator __child_i = __first + __child;
+
+ if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + difference_type(1)))) {
+ // right-child exists and is greater than left-child
+ ++__child_i;
+ ++__child;
+ }
+
+ // check if we are in heap-order
+ if (__comp(*__child_i, *__start))
+ // we are, __start is larger than its largest child
+ return;
+
+ value_type __top(_Ops::__iter_move(__start));
+ do {
+ // we are not in heap-order, swap the parent with its largest child
+ *__start = _Ops::__iter_move(__child_i);
+ __start = __child_i;
+
+ if ((__len - 2) / 2 < __child)
+ break;
+
+ // recompute the child based off of the updated parent
+ __child = 2 * __child + 1;
+ __child_i = __first + __child;
+
+ if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + difference_type(1)))) {
+ // right-child exists and is greater than left-child
+ ++__child_i;
+ ++__child;
+ }
+
+ // check if we are in heap-order
+ } while (!__comp(*__child_i, __top));
+ *__start = std::move(__top);
+}
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _RandomAccessIterator __floyd_sift_down(
+ _RandomAccessIterator __first,
+ _Compare&& __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len) {
+ using difference_type = typename iterator_traits<_RandomAccessIterator>::difference_type;
+ _LIBCPP_ASSERT_INTERNAL(__len >= 2, "shouldn't be called unless __len >= 2");
+
+ _RandomAccessIterator __hole = __first;
+ _RandomAccessIterator __child_i = __first;
+ difference_type __child = 0;
+
+ while (true) {
+ __child_i += difference_type(__child + 1);
+ __child = 2 * __child + 1;
+
+ if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + difference_type(1)))) {
+ // right-child exists and is greater than left-child
+ ++__child_i;
+ ++__child;
+ }
+
+ // swap __hole with its largest child
+ *__hole = _IterOps<_AlgPolicy>::__iter_move(__child_i);
+ __hole = __child_i;
+
+ // if __hole is now a leaf, we're done
+ if (__child > (__len - 2) / 2)
+ return __hole;
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SIFT_DOWN_H
diff --git a/libcxx/include/__cxx03/__algorithm/simd_utils.h b/libcxx/include/__cxx03/__algorithm/simd_utils.h
new file mode 100644
index 00000000000000..549197be80183f
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/simd_utils.h
@@ -0,0 +1,164 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SIMD_UTILS_H
+#define _LIBCPP___ALGORITHM_SIMD_UTILS_H
+
+#include <__algorithm/min.h>
+#include <__bit/bit_cast.h>
+#include <__bit/countl.h>
+#include <__bit/countr.h>
+#include <__config>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__utility/integer_sequence.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+// TODO: Find out how altivec changes things and allow vectorizations there too.
+#if _LIBCPP_STD_VER >= 14 && defined(_LIBCPP_CLANG_VER) && !defined(__ALTIVEC__)
+# define _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS 1
+#else
+# define _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS 0
+#endif
+
+#if _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS && !defined(__OPTIMIZE_SIZE__)
+# define _LIBCPP_VECTORIZE_ALGORITHMS 1
+#else
+# define _LIBCPP_VECTORIZE_ALGORITHMS 0
+#endif
+
+#if _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+inline constexpr bool __can_map_to_integer_v =
+ sizeof(_Tp) == alignof(_Tp) && (sizeof(_Tp) == 1 || sizeof(_Tp) == 2 || sizeof(_Tp) == 4 || sizeof(_Tp) == 8);
+
+template <size_t _TypeSize>
+struct __get_as_integer_type_impl;
+
+template <>
+struct __get_as_integer_type_impl<1> {
+ using type = uint8_t;
+};
+
+template <>
+struct __get_as_integer_type_impl<2> {
+ using type = uint16_t;
+};
+template <>
+struct __get_as_integer_type_impl<4> {
+ using type = uint32_t;
+};
+template <>
+struct __get_as_integer_type_impl<8> {
+ using type = uint64_t;
+};
+
+template <class _Tp>
+using __get_as_integer_type_t = typename __get_as_integer_type_impl<sizeof(_Tp)>::type;
+
+// This isn't specialized for 64 byte vectors on purpose. They have the potential to significantly reduce performance
+// in mixed simd/non-simd workloads and don't provide any performance improvement for currently vectorized algorithms
+// as far as benchmarks are concerned.
+# if defined(__AVX__) || defined(__MVS__)
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 32 / sizeof(_Tp);
+# elif defined(__SSE__) || defined(__ARM_NEON__)
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 16 / sizeof(_Tp);
+# elif defined(__MMX__)
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 8 / sizeof(_Tp);
+# else
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 1;
+# endif
+
+template <class _ArithmeticT, size_t _Np>
+using __simd_vector __attribute__((__ext_vector_type__(_Np))) = _ArithmeticT;
+
+template <class _VecT>
+inline constexpr size_t __simd_vector_size_v = []<bool _False = false>() -> size_t {
+ static_assert(_False, "Not a vector!");
+}();
+
+template <class _Tp, size_t _Np>
+inline constexpr size_t __simd_vector_size_v<__simd_vector<_Tp, _Np>> = _Np;
+
+template <class _Tp, size_t _Np>
+_LIBCPP_HIDE_FROM_ABI _Tp __simd_vector_underlying_type_impl(__simd_vector<_Tp, _Np>) {
+ return _Tp{};
+}
+
+template <class _VecT>
+using __simd_vector_underlying_type_t = decltype(std::__simd_vector_underlying_type_impl(_VecT{}));
+
+// This isn't inlined without always_inline when loading chars.
+template <class _VecT, class _Iter>
+_LIBCPP_NODISCARD _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _VecT __load_vector(_Iter __iter) noexcept {
+ return [=]<size_t... _Indices>(index_sequence<_Indices...>) _LIBCPP_ALWAYS_INLINE noexcept {
+ return _VecT{__iter[_Indices]...};
+ }(make_index_sequence<__simd_vector_size_v<_VecT>>{});
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool __all_of(__simd_vector<_Tp, _Np> __vec) noexcept {
+ return __builtin_reduce_and(__builtin_convertvector(__vec, __simd_vector<bool, _Np>));
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI size_t __find_first_set(__simd_vector<_Tp, _Np> __vec) noexcept {
+ using __mask_vec = __simd_vector<bool, _Np>;
+
+ // This has MSan disabled du to https://github.com/llvm/llvm-project/issues/85876
+ auto __impl = [&]<class _MaskT>(_MaskT) _LIBCPP_NO_SANITIZE("memory") noexcept {
+# if defined(_LIBCPP_BIG_ENDIAN)
+ return std::min<size_t>(
+ _Np, std::__countl_zero(__builtin_bit_cast(_MaskT, __builtin_convertvector(__vec, __mask_vec))));
+# else
+ return std::min<size_t>(
+ _Np, std::__countr_zero(__builtin_bit_cast(_MaskT, __builtin_convertvector(__vec, __mask_vec))));
+# endif
+ };
+
+ if constexpr (sizeof(__mask_vec) == sizeof(uint8_t)) {
+ return __impl(uint8_t{});
+ } else if constexpr (sizeof(__mask_vec) == sizeof(uint16_t)) {
+ return __impl(uint16_t{});
+ } else if constexpr (sizeof(__mask_vec) == sizeof(uint32_t)) {
+ return __impl(uint32_t{});
+ } else if constexpr (sizeof(__mask_vec) == sizeof(uint64_t)) {
+ return __impl(uint64_t{});
+ } else {
+ static_assert(sizeof(__mask_vec) == 0, "unexpected required size for mask integer type");
+ return 0;
+ }
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI size_t __find_first_not_set(__simd_vector<_Tp, _Np> __vec) noexcept {
+ return std::__find_first_set(~__vec);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SIMD_UTILS_H
diff --git a/libcxx/include/__cxx03/__algorithm/sort.h b/libcxx/include/__cxx03/__algorithm/sort.h
new file mode 100644
index 00000000000000..07b5814639e9e4
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/sort.h
@@ -0,0 +1,1016 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SORT_H
+#define _LIBCPP___ALGORITHM_SORT_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iter_swap.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min_element.h>
+#include <__algorithm/partial_sort.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__assert>
+#include <__bit/blsr.h>
+#include <__bit/countl.h>
+#include <__bit/countr.h>
+#include <__config>
+#include <__debug_utils/randomize_range.h>
+#include <__debug_utils/strict_weak_ordering_check.h>
+#include <__functional/operations.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/disjunction.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <climits>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// stable, 2-3 compares, 0-2 swaps
+
+template <class _AlgPolicy, class _Compare, class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 unsigned
+__sort3(_ForwardIterator __x, _ForwardIterator __y, _ForwardIterator __z, _Compare __c) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ unsigned __r = 0;
+ if (!__c(*__y, *__x)) // if x <= y
+ {
+ if (!__c(*__z, *__y)) // if y <= z
+ return __r; // x <= y && y <= z
+ // x <= y && y > z
+ _Ops::iter_swap(__y, __z); // x <= z && y < z
+ __r = 1;
+ if (__c(*__y, *__x)) // if x > y
+ {
+ _Ops::iter_swap(__x, __y); // x < y && y <= z
+ __r = 2;
+ }
+ return __r; // x <= y && y < z
+ }
+ if (__c(*__z, *__y)) // x > y, if y > z
+ {
+ _Ops::iter_swap(__x, __z); // x < y && y < z
+ __r = 1;
+ return __r;
+ }
+ _Ops::iter_swap(__x, __y); // x > y && y <= z
+ __r = 1; // x < y && x <= z
+ if (__c(*__z, *__y)) // if y > z
+ {
+ _Ops::iter_swap(__y, __z); // x <= y && y < z
+ __r = 2;
+ }
+ return __r;
+} // x <= y && y <= z
+
+// stable, 3-6 compares, 0-5 swaps
+
+template <class _AlgPolicy, class _Compare, class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI void
+__sort4(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3, _ForwardIterator __x4, _Compare __c) {
+ using _Ops = _IterOps<_AlgPolicy>;
+ std::__sort3<_AlgPolicy, _Compare>(__x1, __x2, __x3, __c);
+ if (__c(*__x4, *__x3)) {
+ _Ops::iter_swap(__x3, __x4);
+ if (__c(*__x3, *__x2)) {
+ _Ops::iter_swap(__x2, __x3);
+ if (__c(*__x2, *__x1)) {
+ _Ops::iter_swap(__x1, __x2);
+ }
+ }
+ }
+}
+
+// stable, 4-10 compares, 0-9 swaps
+
+template <class _AlgPolicy, class _Comp, class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI void
+__sort5(_ForwardIterator __x1,
+ _ForwardIterator __x2,
+ _ForwardIterator __x3,
+ _ForwardIterator __x4,
+ _ForwardIterator __x5,
+ _Comp __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ std::__sort4<_AlgPolicy, _Comp>(__x1, __x2, __x3, __x4, __comp);
+ if (__comp(*__x5, *__x4)) {
+ _Ops::iter_swap(__x4, __x5);
+ if (__comp(*__x4, *__x3)) {
+ _Ops::iter_swap(__x3, __x4);
+ if (__comp(*__x3, *__x2)) {
+ _Ops::iter_swap(__x2, __x3);
+ if (__comp(*__x2, *__x1)) {
+ _Ops::iter_swap(__x1, __x2);
+ }
+ }
+ }
+ }
+}
+
+// The comparator being simple is a prerequisite for using the branchless optimization.
+template <class _Tp>
+struct __is_simple_comparator : false_type {};
+template <>
+struct __is_simple_comparator<__less<>&> : true_type {};
+template <class _Tp>
+struct __is_simple_comparator<less<_Tp>&> : true_type {};
+template <class _Tp>
+struct __is_simple_comparator<greater<_Tp>&> : true_type {};
+#if _LIBCPP_STD_VER >= 20
+template <>
+struct __is_simple_comparator<ranges::less&> : true_type {};
+template <>
+struct __is_simple_comparator<ranges::greater&> : true_type {};
+#endif
+
+template <class _Compare, class _Iter, class _Tp = typename iterator_traits<_Iter>::value_type>
+using __use_branchless_sort =
+ integral_constant<bool,
+ __libcpp_is_contiguous_iterator<_Iter>::value && sizeof(_Tp) <= sizeof(void*) &&
+ is_arithmetic<_Tp>::value && __is_simple_comparator<_Compare>::value>;
+
+namespace __detail {
+
+// Size in bits for the bitset in use.
+enum { __block_size = sizeof(uint64_t) * 8 };
+
+} // namespace __detail
+
+// Ensures that __c(*__x, *__y) is true by swapping *__x and *__y if necessary.
+template <class _Compare, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI void __cond_swap(_RandomAccessIterator __x, _RandomAccessIterator __y, _Compare __c) {
+ // Note: this function behaves correctly even with proxy iterators (because it relies on `value_type`).
+ using value_type = typename iterator_traits<_RandomAccessIterator>::value_type;
+ bool __r = __c(*__x, *__y);
+ value_type __tmp = __r ? *__x : *__y;
+ *__y = __r ? *__y : *__x;
+ *__x = __tmp;
+}
+
+// Ensures that *__x, *__y and *__z are ordered according to the comparator __c,
+// under the assumption that *__y and *__z are already ordered.
+template <class _Compare, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI void
+__partially_sorted_swap(_RandomAccessIterator __x, _RandomAccessIterator __y, _RandomAccessIterator __z, _Compare __c) {
+ // Note: this function behaves correctly even with proxy iterators (because it relies on `value_type`).
+ using value_type = typename iterator_traits<_RandomAccessIterator>::value_type;
+ bool __r = __c(*__z, *__x);
+ value_type __tmp = __r ? *__z : *__x;
+ *__z = __r ? *__x : *__z;
+ __r = __c(__tmp, *__y);
+ *__x = __r ? *__x : *__y;
+ *__y = __r ? *__y : __tmp;
+}
+
+template <class,
+ class _Compare,
+ class _RandomAccessIterator,
+ __enable_if_t<__use_branchless_sort<_Compare, _RandomAccessIterator>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void __sort3_maybe_branchless(
+ _RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3, _Compare __c) {
+ std::__cond_swap<_Compare>(__x2, __x3, __c);
+ std::__partially_sorted_swap<_Compare>(__x1, __x2, __x3, __c);
+}
+
+template <class _AlgPolicy,
+ class _Compare,
+ class _RandomAccessIterator,
+ __enable_if_t<!__use_branchless_sort<_Compare, _RandomAccessIterator>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void __sort3_maybe_branchless(
+ _RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3, _Compare __c) {
+ std::__sort3<_AlgPolicy, _Compare>(__x1, __x2, __x3, __c);
+}
+
+template <class,
+ class _Compare,
+ class _RandomAccessIterator,
+ __enable_if_t<__use_branchless_sort<_Compare, _RandomAccessIterator>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void __sort4_maybe_branchless(
+ _RandomAccessIterator __x1,
+ _RandomAccessIterator __x2,
+ _RandomAccessIterator __x3,
+ _RandomAccessIterator __x4,
+ _Compare __c) {
+ std::__cond_swap<_Compare>(__x1, __x3, __c);
+ std::__cond_swap<_Compare>(__x2, __x4, __c);
+ std::__cond_swap<_Compare>(__x1, __x2, __c);
+ std::__cond_swap<_Compare>(__x3, __x4, __c);
+ std::__cond_swap<_Compare>(__x2, __x3, __c);
+}
+
+template <class _AlgPolicy,
+ class _Compare,
+ class _RandomAccessIterator,
+ __enable_if_t<!__use_branchless_sort<_Compare, _RandomAccessIterator>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void __sort4_maybe_branchless(
+ _RandomAccessIterator __x1,
+ _RandomAccessIterator __x2,
+ _RandomAccessIterator __x3,
+ _RandomAccessIterator __x4,
+ _Compare __c) {
+ std::__sort4<_AlgPolicy, _Compare>(__x1, __x2, __x3, __x4, __c);
+}
+
+template <class _AlgPolicy,
+ class _Compare,
+ class _RandomAccessIterator,
+ __enable_if_t<__use_branchless_sort<_Compare, _RandomAccessIterator>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void __sort5_maybe_branchless(
+ _RandomAccessIterator __x1,
+ _RandomAccessIterator __x2,
+ _RandomAccessIterator __x3,
+ _RandomAccessIterator __x4,
+ _RandomAccessIterator __x5,
+ _Compare __c) {
+ std::__cond_swap<_Compare>(__x1, __x2, __c);
+ std::__cond_swap<_Compare>(__x4, __x5, __c);
+ std::__partially_sorted_swap<_Compare>(__x3, __x4, __x5, __c);
+ std::__cond_swap<_Compare>(__x2, __x5, __c);
+ std::__partially_sorted_swap<_Compare>(__x1, __x3, __x4, __c);
+ std::__partially_sorted_swap<_Compare>(__x2, __x3, __x4, __c);
+}
+
+template <class _AlgPolicy,
+ class _Compare,
+ class _RandomAccessIterator,
+ __enable_if_t<!__use_branchless_sort<_Compare, _RandomAccessIterator>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void __sort5_maybe_branchless(
+ _RandomAccessIterator __x1,
+ _RandomAccessIterator __x2,
+ _RandomAccessIterator __x3,
+ _RandomAccessIterator __x4,
+ _RandomAccessIterator __x5,
+ _Compare __c) {
+ std::__sort5<_AlgPolicy, _Compare, _RandomAccessIterator>(
+ std::move(__x1), std::move(__x2), std::move(__x3), std::move(__x4), std::move(__x5), __c);
+}
+
+// Assumes size > 0
+template <class _AlgPolicy, class _Compare, class _BidirectionalIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__selection_sort(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp) {
+ _BidirectionalIterator __lm1 = __last;
+ for (--__lm1; __first != __lm1; ++__first) {
+ _BidirectionalIterator __i = std::__min_element<_Compare>(__first, __last, __comp);
+ if (__i != __first)
+ _IterOps<_AlgPolicy>::iter_swap(__first, __i);
+ }
+}
+
+// Sort the iterator range [__first, __last) using the comparator __comp using
+// the insertion sort algorithm.
+template <class _AlgPolicy, class _Compare, class _BidirectionalIterator>
+_LIBCPP_HIDE_FROM_ABI void
+__insertion_sort(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ if (__first == __last)
+ return;
+ _BidirectionalIterator __i = __first;
+ for (++__i; __i != __last; ++__i) {
+ _BidirectionalIterator __j = __i;
+ --__j;
+ if (__comp(*__i, *__j)) {
+ value_type __t(_Ops::__iter_move(__i));
+ _BidirectionalIterator __k = __j;
+ __j = __i;
+ do {
+ *__j = _Ops::__iter_move(__k);
+ __j = __k;
+ } while (__j != __first && __comp(__t, *--__k));
+ *__j = std::move(__t);
+ }
+ }
+}
+
+// Sort the iterator range [__first, __last) using the comparator __comp using
+// the insertion sort algorithm. Insertion sort has two loops, outer and inner.
+// The implementation below has no bounds check (unguarded) for the inner loop.
+// Assumes that there is an element in the position (__first - 1) and that each
+// element in the input range is greater or equal to the element at __first - 1.
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI void
+__insertion_sort_unguarded(_RandomAccessIterator const __first, _RandomAccessIterator __last, _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ if (__first == __last)
+ return;
+ const _RandomAccessIterator __leftmost = __first - difference_type(1);
+ (void)__leftmost; // can be unused when assertions are disabled
+ for (_RandomAccessIterator __i = __first + difference_type(1); __i != __last; ++__i) {
+ _RandomAccessIterator __j = __i - difference_type(1);
+ if (__comp(*__i, *__j)) {
+ value_type __t(_Ops::__iter_move(__i));
+ _RandomAccessIterator __k = __j;
+ __j = __i;
+ do {
+ *__j = _Ops::__iter_move(__k);
+ __j = __k;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __k != __leftmost,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ } while (__comp(__t, *--__k)); // No need for bounds check due to the assumption stated above.
+ *__j = std::move(__t);
+ }
+ }
+}
+
+template <class _AlgPolicy, class _Comp, class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI bool
+__insertion_sort_incomplete(_RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ switch (__last - __first) {
+ case 0:
+ case 1:
+ return true;
+ case 2:
+ if (__comp(*--__last, *__first))
+ _Ops::iter_swap(__first, __last);
+ return true;
+ case 3:
+ std::__sort3_maybe_branchless<_AlgPolicy, _Comp>(__first, __first + difference_type(1), --__last, __comp);
+ return true;
+ case 4:
+ std::__sort4_maybe_branchless<_AlgPolicy, _Comp>(
+ __first, __first + difference_type(1), __first + difference_type(2), --__last, __comp);
+ return true;
+ case 5:
+ std::__sort5_maybe_branchless<_AlgPolicy, _Comp>(
+ __first,
+ __first + difference_type(1),
+ __first + difference_type(2),
+ __first + difference_type(3),
+ --__last,
+ __comp);
+ return true;
+ }
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ _RandomAccessIterator __j = __first + difference_type(2);
+ std::__sort3_maybe_branchless<_AlgPolicy, _Comp>(__first, __first + difference_type(1), __j, __comp);
+ const unsigned __limit = 8;
+ unsigned __count = 0;
+ for (_RandomAccessIterator __i = __j + difference_type(1); __i != __last; ++__i) {
+ if (__comp(*__i, *__j)) {
+ value_type __t(_Ops::__iter_move(__i));
+ _RandomAccessIterator __k = __j;
+ __j = __i;
+ do {
+ *__j = _Ops::__iter_move(__k);
+ __j = __k;
+ } while (__j != __first && __comp(__t, *--__k));
+ *__j = std::move(__t);
+ if (++__count == __limit)
+ return ++__i == __last;
+ }
+ __j = __i;
+ }
+ return true;
+}
+
+template <class _AlgPolicy, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI void __swap_bitmap_pos(
+ _RandomAccessIterator __first, _RandomAccessIterator __last, uint64_t& __left_bitset, uint64_t& __right_bitset) {
+ using _Ops = _IterOps<_AlgPolicy>;
+ typedef typename std::iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ // Swap one pair on each iteration as long as both bitsets have at least one
+ // element for swapping.
+ while (__left_bitset != 0 && __right_bitset != 0) {
+ difference_type __tz_left = __libcpp_ctz(__left_bitset);
+ __left_bitset = __libcpp_blsr(__left_bitset);
+ difference_type __tz_right = __libcpp_ctz(__right_bitset);
+ __right_bitset = __libcpp_blsr(__right_bitset);
+ _Ops::iter_swap(__first + __tz_left, __last - __tz_right);
+ }
+}
+
+template <class _Compare,
+ class _RandomAccessIterator,
+ class _ValueType = typename iterator_traits<_RandomAccessIterator>::value_type>
+inline _LIBCPP_HIDE_FROM_ABI void
+__populate_left_bitset(_RandomAccessIterator __first, _Compare __comp, _ValueType& __pivot, uint64_t& __left_bitset) {
+ // Possible vectorization. With a proper "-march" flag, the following loop
+ // will be compiled into a set of SIMD instructions.
+ _RandomAccessIterator __iter = __first;
+ for (int __j = 0; __j < __detail::__block_size;) {
+ bool __comp_result = !__comp(*__iter, __pivot);
+ __left_bitset |= (static_cast<uint64_t>(__comp_result) << __j);
+ __j++;
+ ++__iter;
+ }
+}
+
+template <class _Compare,
+ class _RandomAccessIterator,
+ class _ValueType = typename iterator_traits<_RandomAccessIterator>::value_type>
+inline _LIBCPP_HIDE_FROM_ABI void
+__populate_right_bitset(_RandomAccessIterator __lm1, _Compare __comp, _ValueType& __pivot, uint64_t& __right_bitset) {
+ // Possible vectorization. With a proper "-march" flag, the following loop
+ // will be compiled into a set of SIMD instructions.
+ _RandomAccessIterator __iter = __lm1;
+ for (int __j = 0; __j < __detail::__block_size;) {
+ bool __comp_result = __comp(*__iter, __pivot);
+ __right_bitset |= (static_cast<uint64_t>(__comp_result) << __j);
+ __j++;
+ --__iter;
+ }
+}
+
+template <class _AlgPolicy,
+ class _Compare,
+ class _RandomAccessIterator,
+ class _ValueType = typename iterator_traits<_RandomAccessIterator>::value_type>
+inline _LIBCPP_HIDE_FROM_ABI void __bitset_partition_partial_blocks(
+ _RandomAccessIterator& __first,
+ _RandomAccessIterator& __lm1,
+ _Compare __comp,
+ _ValueType& __pivot,
+ uint64_t& __left_bitset,
+ uint64_t& __right_bitset) {
+ typedef typename std::iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ difference_type __remaining_len = __lm1 - __first + 1;
+ difference_type __l_size;
+ difference_type __r_size;
+ if (__left_bitset == 0 && __right_bitset == 0) {
+ __l_size = __remaining_len / 2;
+ __r_size = __remaining_len - __l_size;
+ } else if (__left_bitset == 0) {
+ // We know at least one side is a full block.
+ __l_size = __remaining_len - __detail::__block_size;
+ __r_size = __detail::__block_size;
+ } else { // if (__right_bitset == 0)
+ __l_size = __detail::__block_size;
+ __r_size = __remaining_len - __detail::__block_size;
+ }
+ // Record the comparison outcomes for the elements currently on the left side.
+ if (__left_bitset == 0) {
+ _RandomAccessIterator __iter = __first;
+ for (int __j = 0; __j < __l_size; __j++) {
+ bool __comp_result = !__comp(*__iter, __pivot);
+ __left_bitset |= (static_cast<uint64_t>(__comp_result) << __j);
+ ++__iter;
+ }
+ }
+ // Record the comparison outcomes for the elements currently on the right
+ // side.
+ if (__right_bitset == 0) {
+ _RandomAccessIterator __iter = __lm1;
+ for (int __j = 0; __j < __r_size; __j++) {
+ bool __comp_result = __comp(*__iter, __pivot);
+ __right_bitset |= (static_cast<uint64_t>(__comp_result) << __j);
+ --__iter;
+ }
+ }
+ std::__swap_bitmap_pos<_AlgPolicy, _RandomAccessIterator>(__first, __lm1, __left_bitset, __right_bitset);
+ __first += (__left_bitset == 0) ? __l_size : 0;
+ __lm1 -= (__right_bitset == 0) ? __r_size : 0;
+}
+
+template <class _AlgPolicy, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI void __swap_bitmap_pos_within(
+ _RandomAccessIterator& __first, _RandomAccessIterator& __lm1, uint64_t& __left_bitset, uint64_t& __right_bitset) {
+ using _Ops = _IterOps<_AlgPolicy>;
+ typedef typename std::iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ if (__left_bitset) {
+ // Swap within the left side. Need to find set positions in the reverse
+ // order.
+ while (__left_bitset != 0) {
+ difference_type __tz_left = __detail::__block_size - 1 - __libcpp_clz(__left_bitset);
+ __left_bitset &= (static_cast<uint64_t>(1) << __tz_left) - 1;
+ _RandomAccessIterator __it = __first + __tz_left;
+ if (__it != __lm1) {
+ _Ops::iter_swap(__it, __lm1);
+ }
+ --__lm1;
+ }
+ __first = __lm1 + difference_type(1);
+ } else if (__right_bitset) {
+ // Swap within the right side. Need to find set positions in the reverse
+ // order.
+ while (__right_bitset != 0) {
+ difference_type __tz_right = __detail::__block_size - 1 - __libcpp_clz(__right_bitset);
+ __right_bitset &= (static_cast<uint64_t>(1) << __tz_right) - 1;
+ _RandomAccessIterator __it = __lm1 - __tz_right;
+ if (__it != __first) {
+ _Ops::iter_swap(__it, __first);
+ }
+ ++__first;
+ }
+ }
+}
+
+// Partition [__first, __last) using the comparator __comp. *__first has the
+// chosen pivot. Elements that are equivalent are kept to the left of the
+// pivot. Returns the iterator for the pivot and a bool value which is true if
+// the provided range is already sorted, false otherwise. We assume that the
+// length of the range is at least three elements.
+//
+// __bitset_partition uses bitsets for storing outcomes of the comparisons
+// between the pivot and other elements.
+template <class _AlgPolicy, class _RandomAccessIterator, class _Compare>
+_LIBCPP_HIDE_FROM_ABI std::pair<_RandomAccessIterator, bool>
+__bitset_partition(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+ typedef typename std::iterator_traits<_RandomAccessIterator>::value_type value_type;
+ typedef typename std::iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ _LIBCPP_ASSERT_INTERNAL(__last - __first >= difference_type(3), "");
+ const _RandomAccessIterator __begin = __first; // used for bounds checking, those are not moved around
+ const _RandomAccessIterator __end = __last;
+ (void)__end; //
+
+ value_type __pivot(_Ops::__iter_move(__first));
+ // Find the first element greater than the pivot.
+ if (__comp(__pivot, *(__last - difference_type(1)))) {
+ // Not guarded since we know the last element is greater than the pivot.
+ do {
+ ++__first;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __first != __end,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ } while (!__comp(__pivot, *__first));
+ } else {
+ while (++__first < __last && !__comp(__pivot, *__first)) {
+ }
+ }
+ // Find the last element less than or equal to the pivot.
+ if (__first < __last) {
+ // It will be always guarded because __introsort will do the median-of-three
+ // before calling this.
+ do {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __last != __begin,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ --__last;
+ } while (__comp(__pivot, *__last));
+ }
+ // If the first element greater than the pivot is at or after the
+ // last element less than or equal to the pivot, then we have covered the
+ // entire range without swapping elements. This implies the range is already
+ // partitioned.
+ bool __already_partitioned = __first >= __last;
+ if (!__already_partitioned) {
+ _Ops::iter_swap(__first, __last);
+ ++__first;
+ }
+
+ // In [__first, __last) __last is not inclusive. From now on, it uses last
+ // minus one to be inclusive on both sides.
+ _RandomAccessIterator __lm1 = __last - difference_type(1);
+ uint64_t __left_bitset = 0;
+ uint64_t __right_bitset = 0;
+
+ // Reminder: length = __lm1 - __first + 1.
+ while (__lm1 - __first >= 2 * __detail::__block_size - 1) {
+ // Record the comparison outcomes for the elements currently on the left
+ // side.
+ if (__left_bitset == 0)
+ std::__populate_left_bitset<_Compare>(__first, __comp, __pivot, __left_bitset);
+ // Record the comparison outcomes for the elements currently on the right
+ // side.
+ if (__right_bitset == 0)
+ std::__populate_right_bitset<_Compare>(__lm1, __comp, __pivot, __right_bitset);
+ // Swap the elements recorded to be the candidates for swapping in the
+ // bitsets.
+ std::__swap_bitmap_pos<_AlgPolicy, _RandomAccessIterator>(__first, __lm1, __left_bitset, __right_bitset);
+ // Only advance the iterator if all the elements that need to be moved to
+ // other side were moved.
+ __first += (__left_bitset == 0) ? difference_type(__detail::__block_size) : difference_type(0);
+ __lm1 -= (__right_bitset == 0) ? difference_type(__detail::__block_size) : difference_type(0);
+ }
+ // Now, we have a less-than a block worth of elements on at least one of the
+ // sides.
+ std::__bitset_partition_partial_blocks<_AlgPolicy, _Compare>(
+ __first, __lm1, __comp, __pivot, __left_bitset, __right_bitset);
+ // At least one the bitsets would be empty. For the non-empty one, we need to
+ // properly partition the elements that appear within that bitset.
+ std::__swap_bitmap_pos_within<_AlgPolicy>(__first, __lm1, __left_bitset, __right_bitset);
+
+ // Move the pivot to its correct position.
+ _RandomAccessIterator __pivot_pos = __first - difference_type(1);
+ if (__begin != __pivot_pos) {
+ *__begin = _Ops::__iter_move(__pivot_pos);
+ }
+ *__pivot_pos = std::move(__pivot);
+ return std::make_pair(__pivot_pos, __already_partitioned);
+}
+
+// Partition [__first, __last) using the comparator __comp. *__first has the
+// chosen pivot. Elements that are equivalent are kept to the right of the
+// pivot. Returns the iterator for the pivot and a bool value which is true if
+// the provided range is already sorted, false otherwise. We assume that the
+// length of the range is at least three elements.
+template <class _AlgPolicy, class _RandomAccessIterator, class _Compare>
+_LIBCPP_HIDE_FROM_ABI std::pair<_RandomAccessIterator, bool>
+__partition_with_equals_on_right(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef typename std::iterator_traits<_RandomAccessIterator>::value_type value_type;
+ _LIBCPP_ASSERT_INTERNAL(__last - __first >= difference_type(3), "");
+ const _RandomAccessIterator __begin = __first; // used for bounds checking, those are not moved around
+ const _RandomAccessIterator __end = __last;
+ (void)__end; //
+ value_type __pivot(_Ops::__iter_move(__first));
+ // Find the first element greater or equal to the pivot. It will be always
+ // guarded because __introsort will do the median-of-three before calling
+ // this.
+ do {
+ ++__first;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __first != __end,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ } while (__comp(*__first, __pivot));
+
+ // Find the last element less than the pivot.
+ if (__begin == __first - difference_type(1)) {
+ while (__first < __last && !__comp(*--__last, __pivot))
+ ;
+ } else {
+ // Guarded.
+ do {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __last != __begin,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ --__last;
+ } while (!__comp(*__last, __pivot));
+ }
+
+ // If the first element greater than or equal to the pivot is at or after the
+ // last element less than the pivot, then we have covered the entire range
+ // without swapping elements. This implies the range is already partitioned.
+ bool __already_partitioned = __first >= __last;
+ // Go through the remaining elements. Swap pairs of elements (one to the
+ // right of the pivot and the other to left of the pivot) that are not on the
+ // correct side of the pivot.
+ while (__first < __last) {
+ _Ops::iter_swap(__first, __last);
+ do {
+ ++__first;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __first != __end,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ } while (__comp(*__first, __pivot));
+ do {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __last != __begin,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ --__last;
+ } while (!__comp(*__last, __pivot));
+ }
+ // Move the pivot to its correct position.
+ _RandomAccessIterator __pivot_pos = __first - difference_type(1);
+ if (__begin != __pivot_pos) {
+ *__begin = _Ops::__iter_move(__pivot_pos);
+ }
+ *__pivot_pos = std::move(__pivot);
+ return std::make_pair(__pivot_pos, __already_partitioned);
+}
+
+// Similar to the above function. Elements equivalent to the pivot are put to
+// the left of the pivot. Returns the iterator to the pivot element.
+template <class _AlgPolicy, class _RandomAccessIterator, class _Compare>
+_LIBCPP_HIDE_FROM_ABI _RandomAccessIterator
+__partition_with_equals_on_left(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef typename std::iterator_traits<_RandomAccessIterator>::value_type value_type;
+ const _RandomAccessIterator __begin = __first; // used for bounds checking, those are not moved around
+ const _RandomAccessIterator __end = __last;
+ (void)__end; //
+ value_type __pivot(_Ops::__iter_move(__first));
+ if (__comp(__pivot, *(__last - difference_type(1)))) {
+ // Guarded.
+ do {
+ ++__first;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __first != __end,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ } while (!__comp(__pivot, *__first));
+ } else {
+ while (++__first < __last && !__comp(__pivot, *__first)) {
+ }
+ }
+
+ if (__first < __last) {
+ // It will be always guarded because __introsort will do the
+ // median-of-three before calling this.
+ do {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __last != __begin,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ --__last;
+ } while (__comp(__pivot, *__last));
+ }
+ while (__first < __last) {
+ _Ops::iter_swap(__first, __last);
+ do {
+ ++__first;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __first != __end,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ } while (!__comp(__pivot, *__first));
+ do {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __last != __begin,
+ "Would read out of bounds, does your comparator satisfy the strict-weak ordering requirement?");
+ --__last;
+ } while (__comp(__pivot, *__last));
+ }
+ _RandomAccessIterator __pivot_pos = __first - difference_type(1);
+ if (__begin != __pivot_pos) {
+ *__begin = _Ops::__iter_move(__pivot_pos);
+ }
+ *__pivot_pos = std::move(__pivot);
+ return __first;
+}
+
+// The main sorting function. Implements introsort combined with other ideas:
+// - option of using block quick sort for partitioning,
+// - guarded and unguarded insertion sort for small lengths,
+// - Tuckey's ninther technique for computing the pivot,
+// - check on whether partition was not required.
+// The implementation is partly based on Orson Peters' pattern-defeating
+// quicksort, published at: <https://github.com/orlp/pdqsort>.
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator, bool _UseBitSetPartition>
+void __introsort(_RandomAccessIterator __first,
+ _RandomAccessIterator __last,
+ _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __depth,
+ bool __leftmost = true) {
+ using _Ops = _IterOps<_AlgPolicy>;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ using _Comp_ref = __comp_ref_type<_Compare>;
+ // Upper bound for using insertion sort for sorting.
+ _LIBCPP_CONSTEXPR difference_type __limit = 24;
+ // Lower bound for using Tuckey's ninther technique for median computation.
+ _LIBCPP_CONSTEXPR difference_type __ninther_threshold = 128;
+ while (true) {
+ difference_type __len = __last - __first;
+ switch (__len) {
+ case 0:
+ case 1:
+ return;
+ case 2:
+ if (__comp(*--__last, *__first))
+ _Ops::iter_swap(__first, __last);
+ return;
+ case 3:
+ std::__sort3_maybe_branchless<_AlgPolicy, _Compare>(__first, __first + difference_type(1), --__last, __comp);
+ return;
+ case 4:
+ std::__sort4_maybe_branchless<_AlgPolicy, _Compare>(
+ __first, __first + difference_type(1), __first + difference_type(2), --__last, __comp);
+ return;
+ case 5:
+ std::__sort5_maybe_branchless<_AlgPolicy, _Compare>(
+ __first,
+ __first + difference_type(1),
+ __first + difference_type(2),
+ __first + difference_type(3),
+ --__last,
+ __comp);
+ return;
+ }
+ // Use insertion sort if the length of the range is below the specified limit.
+ if (__len < __limit) {
+ if (__leftmost) {
+ std::__insertion_sort<_AlgPolicy, _Compare>(__first, __last, __comp);
+ } else {
+ std::__insertion_sort_unguarded<_AlgPolicy, _Compare>(__first, __last, __comp);
+ }
+ return;
+ }
+ if (__depth == 0) {
+ // Fallback to heap sort as Introsort suggests.
+ std::__partial_sort<_AlgPolicy, _Compare>(__first, __last, __last, __comp);
+ return;
+ }
+ --__depth;
+ {
+ difference_type __half_len = __len / 2;
+ // Use Tuckey's ninther technique or median of 3 for pivot selection
+ // depending on the length of the range being sorted.
+ if (__len > __ninther_threshold) {
+ std::__sort3<_AlgPolicy, _Compare>(__first, __first + __half_len, __last - difference_type(1), __comp);
+ std::__sort3<_AlgPolicy, _Compare>(
+ __first + difference_type(1), __first + (__half_len - 1), __last - difference_type(2), __comp);
+ std::__sort3<_AlgPolicy, _Compare>(
+ __first + difference_type(2), __first + (__half_len + 1), __last - difference_type(3), __comp);
+ std::__sort3<_AlgPolicy, _Compare>(
+ __first + (__half_len - 1), __first + __half_len, __first + (__half_len + 1), __comp);
+ _Ops::iter_swap(__first, __first + __half_len);
+ } else {
+ std::__sort3<_AlgPolicy, _Compare>(__first + __half_len, __first, __last - difference_type(1), __comp);
+ }
+ }
+ // The elements to the left of the current iterator range are already
+ // sorted. If the current iterator range to be sorted is not the
+ // leftmost part of the entire iterator range and the pivot is same as
+ // the highest element in the range to the left, then we know that all
+ // the elements in the range [first, pivot] would be equal to the pivot,
+ // assuming the equal elements are put on the left side when
+ // partitioned. This also means that we do not need to sort the left
+ // side of the partition.
+ if (!__leftmost && !__comp(*(__first - difference_type(1)), *__first)) {
+ __first = std::__partition_with_equals_on_left<_AlgPolicy, _RandomAccessIterator, _Comp_ref>(
+ __first, __last, _Comp_ref(__comp));
+ continue;
+ }
+ // Use bitset partition only if asked for.
+ auto __ret = _UseBitSetPartition
+ ? std::__bitset_partition<_AlgPolicy, _RandomAccessIterator, _Compare>(__first, __last, __comp)
+ : std::__partition_with_equals_on_right<_AlgPolicy, _RandomAccessIterator, _Compare>(
+ __first, __last, __comp);
+ _RandomAccessIterator __i = __ret.first;
+ // [__first, __i) < *__i and *__i <= [__i+1, __last)
+ // If we were given a perfect partition, see if insertion sort is quick...
+ if (__ret.second) {
+ bool __fs = std::__insertion_sort_incomplete<_AlgPolicy, _Compare>(__first, __i, __comp);
+ if (std::__insertion_sort_incomplete<_AlgPolicy, _Compare>(__i + difference_type(1), __last, __comp)) {
+ if (__fs)
+ return;
+ __last = __i;
+ continue;
+ } else {
+ if (__fs) {
+ __first = ++__i;
+ continue;
+ }
+ }
+ }
+ // Sort the left partiton recursively and the right partition with tail recursion elimination.
+ std::__introsort<_AlgPolicy, _Compare, _RandomAccessIterator, _UseBitSetPartition>(
+ __first, __i, __comp, __depth, __leftmost);
+ __leftmost = false;
+ __first = ++__i;
+ }
+}
+
+template <typename _Number>
+inline _LIBCPP_HIDE_FROM_ABI _Number __log2i(_Number __n) {
+ if (__n == 0)
+ return 0;
+ if (sizeof(__n) <= sizeof(unsigned))
+ return sizeof(unsigned) * CHAR_BIT - 1 - __libcpp_clz(static_cast<unsigned>(__n));
+ if (sizeof(__n) <= sizeof(unsigned long))
+ return sizeof(unsigned long) * CHAR_BIT - 1 - __libcpp_clz(static_cast<unsigned long>(__n));
+ if (sizeof(__n) <= sizeof(unsigned long long))
+ return sizeof(unsigned long long) * CHAR_BIT - 1 - __libcpp_clz(static_cast<unsigned long long>(__n));
+
+ _Number __log2 = 0;
+ while (__n > 1) {
+ __log2++;
+ __n >>= 1;
+ }
+ return __log2;
+}
+
+template <class _Comp, class _RandomAccessIterator>
+void __sort(_RandomAccessIterator, _RandomAccessIterator, _Comp);
+
+extern template _LIBCPP_EXPORTED_FROM_ABI void __sort<__less<char>&, char*>(char*, char*, __less<char>&);
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template _LIBCPP_EXPORTED_FROM_ABI void __sort<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&);
+#endif
+extern template _LIBCPP_EXPORTED_FROM_ABI void
+__sort<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void
+__sort<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void __sort<__less<short>&, short*>(short*, short*, __less<short>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void
+__sort<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void __sort<__less<int>&, int*>(int*, int*, __less<int>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void
+__sort<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void __sort<__less<long>&, long*>(long*, long*, __less<long>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void
+__sort<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void
+__sort<__less<long long>&, long long*>(long long*, long long*, __less<long long>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void __sort<__less<unsigned long long>&, unsigned long long*>(
+ unsigned long long*, unsigned long long*, __less<unsigned long long>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void __sort<__less<float>&, float*>(float*, float*, __less<float>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void __sort<__less<double>&, double*>(double*, double*, __less<double>&);
+extern template _LIBCPP_EXPORTED_FROM_ABI void
+__sort<__less<long double>&, long double*>(long double*, long double*, __less<long double>&);
+
+template <class _AlgPolicy, class _RandomAccessIterator, class _Comp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__sort_dispatch(_RandomAccessIterator __first, _RandomAccessIterator __last, _Comp& __comp) {
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ difference_type __depth_limit = 2 * std::__log2i(__last - __first);
+
+ // Only use bitset partitioning for arithmetic types. We should also check
+ // that the default comparator is in use so that we are sure that there are no
+ // branches in the comparator.
+ std::__introsort<_AlgPolicy,
+ _Comp&,
+ _RandomAccessIterator,
+ __use_branchless_sort<_Comp, _RandomAccessIterator>::value>(__first, __last, __comp, __depth_limit);
+}
+
+template <class _Type, class... _Options>
+using __is_any_of = _Or<is_same<_Type, _Options>...>;
+
+template <class _Type>
+using __sort_is_specialized_in_library = __is_any_of<
+ _Type,
+ char,
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ wchar_t,
+#endif
+ signed char,
+ unsigned char,
+ short,
+ unsigned short,
+ int,
+ unsigned int,
+ long,
+ unsigned long,
+ long long,
+ unsigned long long,
+ float,
+ double,
+ long double>;
+
+template <class _AlgPolicy, class _Type, __enable_if_t<__sort_is_specialized_in_library<_Type>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void __sort_dispatch(_Type* __first, _Type* __last, __less<>&) {
+ __less<_Type> __comp;
+ std::__sort<__less<_Type>&, _Type*>(__first, __last, __comp);
+}
+
+template <class _AlgPolicy, class _Type, __enable_if_t<__sort_is_specialized_in_library<_Type>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void __sort_dispatch(_Type* __first, _Type* __last, less<_Type>&) {
+ __less<_Type> __comp;
+ std::__sort<__less<_Type>&, _Type*>(__first, __last, __comp);
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _AlgPolicy, class _Type, __enable_if_t<__sort_is_specialized_in_library<_Type>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void __sort_dispatch(_Type* __first, _Type* __last, less<>&) {
+ __less<_Type> __comp;
+ std::__sort<__less<_Type>&, _Type*>(__first, __last, __comp);
+}
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+template <class _AlgPolicy, class _Type, __enable_if_t<__sort_is_specialized_in_library<_Type>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void __sort_dispatch(_Type* __first, _Type* __last, ranges::less&) {
+ __less<_Type> __comp;
+ std::__sort<__less<_Type>&, _Type*>(__first, __last, __comp);
+}
+#endif
+
+template <class _AlgPolicy, class _RandomAccessIterator, class _Comp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__sort_impl(_RandomAccessIterator __first, _RandomAccessIterator __last, _Comp& __comp) {
+ std::__debug_randomize_range<_AlgPolicy>(__first, __last);
+
+ if (__libcpp_is_constant_evaluated()) {
+ std::__partial_sort<_AlgPolicy>(
+ std::__unwrap_iter(__first), std::__unwrap_iter(__last), std::__unwrap_iter(__last), __comp);
+ } else {
+ std::__sort_dispatch<_AlgPolicy>(std::__unwrap_iter(__first), std::__unwrap_iter(__last), __comp);
+ }
+ std::__check_strict_weak_ordering_sorted(std::__unwrap_iter(__first), std::__unwrap_iter(__last), __comp);
+}
+
+template <class _RandomAccessIterator, class _Comp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
+ std::__sort_impl<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+sort(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ std::sort(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SORT_H
diff --git a/libcxx/include/__cxx03/__algorithm/sort_heap.h b/libcxx/include/__cxx03/__algorithm/sort_heap.h
new file mode 100644
index 00000000000000..f20b110c7fd12e
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/sort_heap.h
@@ -0,0 +1,63 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SORT_HEAP_H
+#define _LIBCPP___ALGORITHM_SORT_HEAP_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/pop_heap.h>
+#include <__config>
+#include <__debug_utils/strict_weak_ordering_check.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare&& __comp) {
+ _RandomAccessIterator __saved_last = __last;
+ __comp_ref_type<_Compare> __comp_ref = __comp;
+
+ using difference_type = typename iterator_traits<_RandomAccessIterator>::difference_type;
+ for (difference_type __n = __last - __first; __n > 1; --__last, (void)--__n)
+ std::__pop_heap<_AlgPolicy>(__first, __last, __comp_ref, __n);
+ std::__check_strict_weak_ordering_sorted(__first, __saved_last, __comp_ref);
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ static_assert(std::is_copy_constructible<_RandomAccessIterator>::value, "Iterators must be copy constructible.");
+ static_assert(std::is_copy_assignable<_RandomAccessIterator>::value, "Iterators must be copy assignable.");
+
+ std::__sort_heap<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ std::sort_heap(std::move(__first), std::move(__last), __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SORT_HEAP_H
diff --git a/libcxx/include/__cxx03/__algorithm/stable_partition.h b/libcxx/include/__cxx03/__algorithm/stable_partition.h
new file mode 100644
index 00000000000000..8bb1eaf2d22495
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/stable_partition.h
@@ -0,0 +1,307 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_STABLE_PARTITION_H
+#define _LIBCPP___ALGORITHM_STABLE_PARTITION_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/rotate.h>
+#include <__config>
+#include <__iterator/advance.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/destruct_n.h>
+#include <__memory/temporary_buffer.h>
+#include <__memory/unique_ptr.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Predicate, class _ForwardIterator, class _Distance, class _Pair>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator __stable_partition_impl(
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _Predicate __pred,
+ _Distance __len,
+ _Pair __p,
+ forward_iterator_tag __fit) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ // *__first is known to be false
+ // __len >= 1
+ if (__len == 1)
+ return __first;
+ if (__len == 2) {
+ _ForwardIterator __m = __first;
+ if (__pred(*++__m)) {
+ _Ops::iter_swap(__first, __m);
+ return __m;
+ }
+ return __first;
+ }
+ if (__len <= __p.second) { // The buffer is big enough to use
+ typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
+ // Move the falses into the temporary buffer, and the trues to the front of the line
+ // Update __first to always point to the end of the trues
+ value_type* __t = __p.first;
+ ::new ((void*)__t) value_type(_Ops::__iter_move(__first));
+ __d.template __incr<value_type>();
+ ++__t;
+ _ForwardIterator __i = __first;
+ while (++__i != __last) {
+ if (__pred(*__i)) {
+ *__first = _Ops::__iter_move(__i);
+ ++__first;
+ } else {
+ ::new ((void*)__t) value_type(_Ops::__iter_move(__i));
+ __d.template __incr<value_type>();
+ ++__t;
+ }
+ }
+ // All trues now at start of range, all falses in buffer
+ // Move falses back into range, but don't mess up __first which points to first false
+ __i = __first;
+ for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void)++__i)
+ *__i = _Ops::__iter_move(__t2);
+ // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
+ return __first;
+ }
+ // Else not enough buffer, do in place
+ // __len >= 3
+ _ForwardIterator __m = __first;
+ _Distance __len2 = __len / 2; // __len2 >= 2
+ _Ops::advance(__m, __len2);
+ // recurse on [__first, __m), *__first know to be false
+ // F?????????????????
+ // f m l
+ _ForwardIterator __first_false =
+ std::__stable_partition_impl<_AlgPolicy, _Predicate&>(__first, __m, __pred, __len2, __p, __fit);
+ // TTTFFFFF??????????
+ // f ff m l
+ // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
+ _ForwardIterator __m1 = __m;
+ _ForwardIterator __second_false = __last;
+ _Distance __len_half = __len - __len2;
+ while (__pred(*__m1)) {
+ if (++__m1 == __last)
+ goto __second_half_done;
+ --__len_half;
+ }
+ // TTTFFFFFTTTF??????
+ // f ff m m1 l
+ __second_false = std::__stable_partition_impl<_AlgPolicy, _Predicate&>(__m1, __last, __pred, __len_half, __p, __fit);
+__second_half_done:
+ // TTTFFFFFTTTTTFFFFF
+ // f ff m sf l
+ return std::__rotate<_AlgPolicy>(__first_false, __m, __second_false).first;
+ // TTTTTTTTFFFFFFFFFF
+ // |
+}
+
+template <class _AlgPolicy, class _Predicate, class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator
+__stable_partition_impl(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, forward_iterator_tag) {
+ typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
+
+ const difference_type __alloc_limit = 3; // might want to make this a function of trivial assignment
+ // Either prove all true and return __first or point to first false
+ while (true) {
+ if (__first == __last)
+ return __first;
+ if (!__pred(*__first))
+ break;
+ ++__first;
+ }
+ // We now have a reduced range [__first, __last)
+ // *__first is known to be false
+ difference_type __len = _IterOps<_AlgPolicy>::distance(__first, __last);
+ pair<value_type*, ptrdiff_t> __p(0, 0);
+ unique_ptr<value_type, __return_temporary_buffer> __h;
+ if (__len >= __alloc_limit) {
+ // TODO: Remove the use of std::get_temporary_buffer
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ __p = std::get_temporary_buffer<value_type>(__len);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ __h.reset(__p.first);
+ }
+ return std::__stable_partition_impl<_AlgPolicy, _Predicate&>(
+ std::move(__first), std::move(__last), __pred, __len, __p, forward_iterator_tag());
+}
+
+template <class _AlgPolicy, class _Predicate, class _BidirectionalIterator, class _Distance, class _Pair>
+_BidirectionalIterator __stable_partition_impl(
+ _BidirectionalIterator __first,
+ _BidirectionalIterator __last,
+ _Predicate __pred,
+ _Distance __len,
+ _Pair __p,
+ bidirectional_iterator_tag __bit) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ // *__first is known to be false
+ // *__last is known to be true
+ // __len >= 2
+ if (__len == 2) {
+ _Ops::iter_swap(__first, __last);
+ return __last;
+ }
+ if (__len == 3) {
+ _BidirectionalIterator __m = __first;
+ if (__pred(*++__m)) {
+ _Ops::iter_swap(__first, __m);
+ _Ops::iter_swap(__m, __last);
+ return __last;
+ }
+ _Ops::iter_swap(__m, __last);
+ _Ops::iter_swap(__first, __m);
+ return __m;
+ }
+ if (__len <= __p.second) { // The buffer is big enough to use
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
+ // Move the falses into the temporary buffer, and the trues to the front of the line
+ // Update __first to always point to the end of the trues
+ value_type* __t = __p.first;
+ ::new ((void*)__t) value_type(_Ops::__iter_move(__first));
+ __d.template __incr<value_type>();
+ ++__t;
+ _BidirectionalIterator __i = __first;
+ while (++__i != __last) {
+ if (__pred(*__i)) {
+ *__first = _Ops::__iter_move(__i);
+ ++__first;
+ } else {
+ ::new ((void*)__t) value_type(_Ops::__iter_move(__i));
+ __d.template __incr<value_type>();
+ ++__t;
+ }
+ }
+ // move *__last, known to be true
+ *__first = _Ops::__iter_move(__i);
+ __i = ++__first;
+ // All trues now at start of range, all falses in buffer
+ // Move falses back into range, but don't mess up __first which points to first false
+ for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void)++__i)
+ *__i = _Ops::__iter_move(__t2);
+ // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
+ return __first;
+ }
+ // Else not enough buffer, do in place
+ // __len >= 4
+ _BidirectionalIterator __m = __first;
+ _Distance __len2 = __len / 2; // __len2 >= 2
+ _Ops::advance(__m, __len2);
+ // recurse on [__first, __m-1], except reduce __m-1 until *(__m-1) is true, *__first know to be false
+ // F????????????????T
+ // f m l
+ _BidirectionalIterator __m1 = __m;
+ _BidirectionalIterator __first_false = __first;
+ _Distance __len_half = __len2;
+ while (!__pred(*--__m1)) {
+ if (__m1 == __first)
+ goto __first_half_done;
+ --__len_half;
+ }
+ // F???TFFF?????????T
+ // f m1 m l
+ __first_false = std::__stable_partition_impl<_AlgPolicy, _Predicate&>(__first, __m1, __pred, __len_half, __p, __bit);
+__first_half_done:
+ // TTTFFFFF?????????T
+ // f ff m l
+ // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
+ __m1 = __m;
+ _BidirectionalIterator __second_false = __last;
+ ++__second_false;
+ __len_half = __len - __len2;
+ while (__pred(*__m1)) {
+ if (++__m1 == __last)
+ goto __second_half_done;
+ --__len_half;
+ }
+ // TTTFFFFFTTTF?????T
+ // f ff m m1 l
+ __second_false = std::__stable_partition_impl<_AlgPolicy, _Predicate&>(__m1, __last, __pred, __len_half, __p, __bit);
+__second_half_done:
+ // TTTFFFFFTTTTTFFFFF
+ // f ff m sf l
+ return std::__rotate<_AlgPolicy>(__first_false, __m, __second_false).first;
+ // TTTTTTTTFFFFFFFFFF
+ // |
+}
+
+template <class _AlgPolicy, class _Predicate, class _BidirectionalIterator>
+_LIBCPP_HIDE_FROM_ABI _BidirectionalIterator __stable_partition_impl(
+ _BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred, bidirectional_iterator_tag) {
+ typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ const difference_type __alloc_limit = 4; // might want to make this a function of trivial assignment
+ // Either prove all true and return __first or point to first false
+ while (true) {
+ if (__first == __last)
+ return __first;
+ if (!__pred(*__first))
+ break;
+ ++__first;
+ }
+ // __first points to first false, everything prior to __first is already set.
+ // Either prove [__first, __last) is all false and return __first, or point __last to last true
+ do {
+ if (__first == --__last)
+ return __first;
+ } while (!__pred(*__last));
+ // We now have a reduced range [__first, __last]
+ // *__first is known to be false
+ // *__last is known to be true
+ // __len >= 2
+ difference_type __len = _IterOps<_AlgPolicy>::distance(__first, __last) + 1;
+ pair<value_type*, ptrdiff_t> __p(0, 0);
+ unique_ptr<value_type, __return_temporary_buffer> __h;
+ if (__len >= __alloc_limit) {
+ // TODO: Remove the use of std::get_temporary_buffer
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ __p = std::get_temporary_buffer<value_type>(__len);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ __h.reset(__p.first);
+ }
+ return std::__stable_partition_impl<_AlgPolicy, _Predicate&>(
+ std::move(__first), std::move(__last), __pred, __len, __p, bidirectional_iterator_tag());
+}
+
+template <class _AlgPolicy, class _Predicate, class _ForwardIterator, class _IterCategory>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator __stable_partition(
+ _ForwardIterator __first, _ForwardIterator __last, _Predicate&& __pred, _IterCategory __iter_category) {
+ return std::__stable_partition_impl<_AlgPolicy, __remove_cvref_t<_Predicate>&>(
+ std::move(__first), std::move(__last), __pred, __iter_category);
+}
+
+template <class _ForwardIterator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ using _IterCategory = typename iterator_traits<_ForwardIterator>::iterator_category;
+ return std::__stable_partition<_ClassicAlgPolicy, _Predicate&>(
+ std::move(__first), std::move(__last), __pred, _IterCategory());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_STABLE_PARTITION_H
diff --git a/libcxx/include/__cxx03/__algorithm/stable_sort.h b/libcxx/include/__cxx03/__algorithm/stable_sort.h
new file mode 100644
index 00000000000000..726e7e16b3564a
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/stable_sort.h
@@ -0,0 +1,273 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_STABLE_SORT_H
+#define _LIBCPP___ALGORITHM_STABLE_SORT_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/inplace_merge.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/sort.h>
+#include <__config>
+#include <__debug_utils/strict_weak_ordering_check.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/destruct_n.h>
+#include <__memory/temporary_buffer.h>
+#include <__memory/unique_ptr.h>
+#include <__type_traits/is_trivially_assignable.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _BidirectionalIterator>
+_LIBCPP_HIDE_FROM_ABI void __insertion_sort_move(
+ _BidirectionalIterator __first1,
+ _BidirectionalIterator __last1,
+ typename iterator_traits<_BidirectionalIterator>::value_type* __first2,
+ _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ if (__first1 != __last1) {
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h(__first2, __d);
+ value_type* __last2 = __first2;
+ ::new ((void*)__last2) value_type(_Ops::__iter_move(__first1));
+ __d.template __incr<value_type>();
+ for (++__last2; ++__first1 != __last1; ++__last2) {
+ value_type* __j2 = __last2;
+ value_type* __i2 = __j2;
+ if (__comp(*__first1, *--__i2)) {
+ ::new ((void*)__j2) value_type(std::move(*__i2));
+ __d.template __incr<value_type>();
+ for (--__j2; __i2 != __first2 && __comp(*__first1, *--__i2); --__j2)
+ *__j2 = std::move(*__i2);
+ *__j2 = _Ops::__iter_move(__first1);
+ } else {
+ ::new ((void*)__j2) value_type(_Ops::__iter_move(__first1));
+ __d.template __incr<value_type>();
+ }
+ }
+ __h.release();
+ }
+}
+
+template <class _AlgPolicy, class _Compare, class _InputIterator1, class _InputIterator2>
+_LIBCPP_HIDE_FROM_ABI void __merge_move_construct(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ typename iterator_traits<_InputIterator1>::value_type* __result,
+ _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ typedef typename iterator_traits<_InputIterator1>::value_type value_type;
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h(__result, __d);
+ for (; true; ++__result) {
+ if (__first1 == __last1) {
+ for (; __first2 != __last2; ++__first2, (void)++__result, __d.template __incr<value_type>())
+ ::new ((void*)__result) value_type(_Ops::__iter_move(__first2));
+ __h.release();
+ return;
+ }
+ if (__first2 == __last2) {
+ for (; __first1 != __last1; ++__first1, (void)++__result, __d.template __incr<value_type>())
+ ::new ((void*)__result) value_type(_Ops::__iter_move(__first1));
+ __h.release();
+ return;
+ }
+ if (__comp(*__first2, *__first1)) {
+ ::new ((void*)__result) value_type(_Ops::__iter_move(__first2));
+ __d.template __incr<value_type>();
+ ++__first2;
+ } else {
+ ::new ((void*)__result) value_type(_Ops::__iter_move(__first1));
+ __d.template __incr<value_type>();
+ ++__first1;
+ }
+ }
+}
+
+template <class _AlgPolicy, class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI void __merge_move_assign(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _InputIterator2 __last2,
+ _OutputIterator __result,
+ _Compare __comp) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ for (; __first1 != __last1; ++__result) {
+ if (__first2 == __last2) {
+ for (; __first1 != __last1; ++__first1, (void)++__result)
+ *__result = _Ops::__iter_move(__first1);
+ return;
+ }
+ if (__comp(*__first2, *__first1)) {
+ *__result = _Ops::__iter_move(__first2);
+ ++__first2;
+ } else {
+ *__result = _Ops::__iter_move(__first1);
+ ++__first1;
+ }
+ }
+ for (; __first2 != __last2; ++__first2, (void)++__result)
+ *__result = _Ops::__iter_move(__first2);
+}
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+void __stable_sort(_RandomAccessIterator __first,
+ _RandomAccessIterator __last,
+ _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len,
+ typename iterator_traits<_RandomAccessIterator>::value_type* __buff,
+ ptrdiff_t __buff_size);
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+void __stable_sort_move(_RandomAccessIterator __first1,
+ _RandomAccessIterator __last1,
+ _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len,
+ typename iterator_traits<_RandomAccessIterator>::value_type* __first2) {
+ using _Ops = _IterOps<_AlgPolicy>;
+
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ switch (__len) {
+ case 0:
+ return;
+ case 1:
+ ::new ((void*)__first2) value_type(_Ops::__iter_move(__first1));
+ return;
+ case 2:
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h2(__first2, __d);
+ if (__comp(*--__last1, *__first1)) {
+ ::new ((void*)__first2) value_type(_Ops::__iter_move(__last1));
+ __d.template __incr<value_type>();
+ ++__first2;
+ ::new ((void*)__first2) value_type(_Ops::__iter_move(__first1));
+ } else {
+ ::new ((void*)__first2) value_type(_Ops::__iter_move(__first1));
+ __d.template __incr<value_type>();
+ ++__first2;
+ ::new ((void*)__first2) value_type(_Ops::__iter_move(__last1));
+ }
+ __h2.release();
+ return;
+ }
+ if (__len <= 8) {
+ std::__insertion_sort_move<_AlgPolicy, _Compare>(__first1, __last1, __first2, __comp);
+ return;
+ }
+ typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
+ _RandomAccessIterator __m = __first1 + __l2;
+ std::__stable_sort<_AlgPolicy, _Compare>(__first1, __m, __comp, __l2, __first2, __l2);
+ std::__stable_sort<_AlgPolicy, _Compare>(__m, __last1, __comp, __len - __l2, __first2 + __l2, __len - __l2);
+ std::__merge_move_construct<_AlgPolicy, _Compare>(__first1, __m, __m, __last1, __first2, __comp);
+}
+
+template <class _Tp>
+struct __stable_sort_switch {
+ static const unsigned value = 128 * is_trivially_copy_assignable<_Tp>::value;
+};
+
+template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
+void __stable_sort(_RandomAccessIterator __first,
+ _RandomAccessIterator __last,
+ _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len,
+ typename iterator_traits<_RandomAccessIterator>::value_type* __buff,
+ ptrdiff_t __buff_size) {
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ switch (__len) {
+ case 0:
+ case 1:
+ return;
+ case 2:
+ if (__comp(*--__last, *__first))
+ _IterOps<_AlgPolicy>::iter_swap(__first, __last);
+ return;
+ }
+ if (__len <= static_cast<difference_type>(__stable_sort_switch<value_type>::value)) {
+ std::__insertion_sort<_AlgPolicy, _Compare>(__first, __last, __comp);
+ return;
+ }
+ typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
+ _RandomAccessIterator __m = __first + __l2;
+ if (__len <= __buff_size) {
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
+ std::__stable_sort_move<_AlgPolicy, _Compare>(__first, __m, __comp, __l2, __buff);
+ __d.__set(__l2, (value_type*)nullptr);
+ std::__stable_sort_move<_AlgPolicy, _Compare>(__m, __last, __comp, __len - __l2, __buff + __l2);
+ __d.__set(__len, (value_type*)nullptr);
+ std::__merge_move_assign<_AlgPolicy, _Compare>(
+ __buff, __buff + __l2, __buff + __l2, __buff + __len, __first, __comp);
+ // std::__merge<_Compare>(move_iterator<value_type*>(__buff),
+ // move_iterator<value_type*>(__buff + __l2),
+ // move_iterator<_RandomAccessIterator>(__buff + __l2),
+ // move_iterator<_RandomAccessIterator>(__buff + __len),
+ // __first, __comp);
+ return;
+ }
+ std::__stable_sort<_AlgPolicy, _Compare>(__first, __m, __comp, __l2, __buff, __buff_size);
+ std::__stable_sort<_AlgPolicy, _Compare>(__m, __last, __comp, __len - __l2, __buff, __buff_size);
+ std::__inplace_merge<_AlgPolicy>(__first, __m, __last, __comp, __l2, __len - __l2, __buff, __buff_size);
+}
+
+template <class _AlgPolicy, class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI void
+__stable_sort_impl(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare& __comp) {
+ using value_type = typename iterator_traits<_RandomAccessIterator>::value_type;
+ using difference_type = typename iterator_traits<_RandomAccessIterator>::difference_type;
+
+ difference_type __len = __last - __first;
+ pair<value_type*, ptrdiff_t> __buf(0, 0);
+ unique_ptr<value_type, __return_temporary_buffer> __h;
+ if (__len > static_cast<difference_type>(__stable_sort_switch<value_type>::value)) {
+ // TODO: Remove the use of std::get_temporary_buffer
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ __buf = std::get_temporary_buffer<value_type>(__len);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ __h.reset(__buf.first);
+ }
+
+ std::__stable_sort<_AlgPolicy, __comp_ref_type<_Compare> >(__first, __last, __comp, __len, __buf.first, __buf.second);
+ std::__check_strict_weak_ordering_sorted(__first, __last, __comp);
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_HIDE_FROM_ABI void
+stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
+ std::__stable_sort_impl<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI void stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ std::stable_sort(__first, __last, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_STABLE_SORT_H
diff --git a/libcxx/include/__cxx03/__algorithm/swap_ranges.h b/libcxx/include/__cxx03/__algorithm/swap_ranges.h
new file mode 100644
index 00000000000000..54b453b72360e0
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/swap_ranges.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SWAP_RANGES_H
+#define _LIBCPP___ALGORITHM_SWAP_RANGES_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// 2+2 iterators: the shorter size will be used.
+template <class _AlgPolicy, class _ForwardIterator1, class _Sentinel1, class _ForwardIterator2, class _Sentinel2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator1, _ForwardIterator2>
+__swap_ranges(_ForwardIterator1 __first1, _Sentinel1 __last1, _ForwardIterator2 __first2, _Sentinel2 __last2) {
+ while (__first1 != __last1 && __first2 != __last2) {
+ _IterOps<_AlgPolicy>::iter_swap(__first1, __first2);
+ ++__first1;
+ ++__first2;
+ }
+
+ return pair<_ForwardIterator1, _ForwardIterator2>(std::move(__first1), std::move(__first2));
+}
+
+// 2+1 iterators: size2 >= size1.
+template <class _AlgPolicy, class _ForwardIterator1, class _Sentinel1, class _ForwardIterator2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator1, _ForwardIterator2>
+__swap_ranges(_ForwardIterator1 __first1, _Sentinel1 __last1, _ForwardIterator2 __first2) {
+ while (__first1 != __last1) {
+ _IterOps<_AlgPolicy>::iter_swap(__first1, __first2);
+ ++__first1;
+ ++__first2;
+ }
+
+ return pair<_ForwardIterator1, _ForwardIterator2>(std::move(__first1), std::move(__first2));
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator2
+swap_ranges(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2) {
+ return std::__swap_ranges<_ClassicAlgPolicy>(std::move(__first1), std::move(__last1), std::move(__first2)).second;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SWAP_RANGES_H
diff --git a/libcxx/include/__cxx03/__algorithm/three_way_comp_ref_type.h b/libcxx/include/__cxx03/__algorithm/three_way_comp_ref_type.h
new file mode 100644
index 00000000000000..5702a1fee08262
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/three_way_comp_ref_type.h
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_THREE_WAY_COMP_REF_TYPE_H
+#define _LIBCPP___ALGORITHM_THREE_WAY_COMP_REF_TYPE_H
+
+#include <__assert>
+#include <__compare/ordering.h>
+#include <__config>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Comp>
+struct __debug_three_way_comp {
+ _Comp& __comp_;
+ _LIBCPP_HIDE_FROM_ABI constexpr __debug_three_way_comp(_Comp& __c) : __comp_(__c) {}
+
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(const _Tp& __x, const _Up& __y) {
+ auto __r = __comp_(__x, __y);
+ if constexpr (__comparison_category<decltype(__comp_(__x, __y))>)
+ __do_compare_assert(__y, __x, __r);
+ return __r;
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp& __x, _Up& __y) {
+ auto __r = __comp_(__x, __y);
+ if constexpr (__comparison_category<decltype(__comp_(__x, __y))>)
+ __do_compare_assert(__y, __x, __r);
+ return __r;
+ }
+
+ template <class _LHS, class _RHS, class _Order>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __do_compare_assert(_LHS& __l, _RHS& __r, _Order __o) {
+ _Order __expected = __o;
+ if (__o == _Order::less)
+ __expected = _Order::greater;
+ if (__o == _Order::greater)
+ __expected = _Order::less;
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ __comp_(__l, __r) == __expected, "Comparator does not induce a strict weak ordering");
+ (void)__l;
+ (void)__r;
+ }
+};
+
+// Pass the comparator by lvalue reference. Or in the debug mode, using a debugging wrapper that stores a reference.
+# if _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_DEBUG
+template <class _Comp>
+using __three_way_comp_ref_type = __debug_three_way_comp<_Comp>;
+# else
+template <class _Comp>
+using __three_way_comp_ref_type = _Comp&;
+# endif
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_THREE_WAY_COMP_REF_TYPE_H
diff --git a/libcxx/include/__cxx03/__algorithm/transform.h b/libcxx/include/__cxx03/__algorithm/transform.h
new file mode 100644
index 00000000000000..1b424409591cec
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/transform.h
@@ -0,0 +1,42 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_TRANSFORM_H
+#define _LIBCPP___ALGORITHM_TRANSFORM_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator, class _UnaryOperation>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+transform(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _UnaryOperation __op) {
+ for (; __first != __last; ++__first, (void)++__result)
+ *__result = __op(*__first);
+ return __result;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _BinaryOperation>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator transform(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _OutputIterator __result,
+ _BinaryOperation __binary_op) {
+ for (; __first1 != __last1; ++__first1, (void)++__first2, ++__result)
+ *__result = __binary_op(*__first1, *__first2);
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_TRANSFORM_H
diff --git a/libcxx/include/__cxx03/__algorithm/uniform_random_bit_generator_adaptor.h b/libcxx/include/__cxx03/__algorithm/uniform_random_bit_generator_adaptor.h
new file mode 100644
index 00000000000000..aef0fbfb7c2842
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/uniform_random_bit_generator_adaptor.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_UNIFORM_RANDOM_BIT_GENERATOR_ADAPTOR_H
+#define _LIBCPP___ALGORITHM_RANGES_UNIFORM_RANDOM_BIT_GENERATOR_ADAPTOR_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__type_traits/remove_cvref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Range versions of random algorithms (e.g. `std::shuffle`) are less constrained than their classic counterparts.
+// Range algorithms only require the given generator to satisfy the `std::uniform_random_bit_generator` concept.
+// Classic algorithms require the given generator to meet the uniform random bit generator requirements; these
+// requirements include satisfying `std::uniform_random_bit_generator` and add a requirement for the generator to
+// provide a nested `result_type` typedef (see `[rand.req.urng]`).
+//
+// To be able to reuse classic implementations, make the given generator meet the classic requirements by wrapping
+// it into an adaptor type that forwards all of its interface and adds the required typedef.
+template <class _Gen>
+class _ClassicGenAdaptor {
+private:
+ // The generator is not required to be copyable or movable, so it has to be stored as a reference.
+ _Gen& __gen_;
+
+public:
+ using result_type = invoke_result_t<_Gen&>;
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto min() { return __remove_cvref_t<_Gen>::min(); }
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto max() { return __remove_cvref_t<_Gen>::max(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit _ClassicGenAdaptor(_Gen& __g) : __gen_(__g) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()() const { return __gen_(); }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___ALGORITHM_RANGES_UNIFORM_RANDOM_BIT_GENERATOR_ADAPTOR_H
diff --git a/libcxx/include/__cxx03/__algorithm/unique.h b/libcxx/include/__cxx03/__algorithm/unique.h
new file mode 100644
index 00000000000000..d597014596f2ea
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/unique.h
@@ -0,0 +1,64 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_UNIQUE_H
+#define _LIBCPP___ALGORITHM_UNIQUE_H
+
+#include <__algorithm/adjacent_find.h>
+#include <__algorithm/comp.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// unique
+
+template <class _AlgPolicy, class _Iter, class _Sent, class _BinaryPredicate>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 std::pair<_Iter, _Iter>
+__unique(_Iter __first, _Sent __last, _BinaryPredicate&& __pred) {
+ __first = std::__adjacent_find(__first, __last, __pred);
+ if (__first != __last) {
+ // ... a a ? ...
+ // f i
+ _Iter __i = __first;
+ for (++__i; ++__i != __last;)
+ if (!__pred(*__first, *__i))
+ *++__first = _IterOps<_AlgPolicy>::__iter_move(__i);
+ ++__first;
+ return std::pair<_Iter, _Iter>(std::move(__first), std::move(__i));
+ }
+ return std::pair<_Iter, _Iter>(__first, __first);
+}
+
+template <class _ForwardIterator, class _BinaryPredicate>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+unique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred) {
+ return std::__unique<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __pred).first;
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+unique(_ForwardIterator __first, _ForwardIterator __last) {
+ return std::unique(__first, __last, __equal_to());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_UNIQUE_H
diff --git a/libcxx/include/__cxx03/__algorithm/unique_copy.h b/libcxx/include/__cxx03/__algorithm/unique_copy.h
new file mode 100644
index 00000000000000..16ce80cab32f0d
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/unique_copy.h
@@ -0,0 +1,127 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_UNIQUE_COPY_H
+#define _LIBCPP___ALGORITHM_UNIQUE_COPY_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_base_of.h>
+#include <__type_traits/is_same.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __unique_copy_tags {
+
+struct __reread_from_input_tag {};
+struct __reread_from_output_tag {};
+struct __read_from_tmp_value_tag {};
+
+} // namespace __unique_copy_tags
+
+template <class _AlgPolicy, class _BinaryPredicate, class _InputIterator, class _Sent, class _OutputIterator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _OutputIterator>
+__unique_copy(_InputIterator __first,
+ _Sent __last,
+ _OutputIterator __result,
+ _BinaryPredicate&& __pred,
+ __unique_copy_tags::__read_from_tmp_value_tag) {
+ if (__first != __last) {
+ typename _IterOps<_AlgPolicy>::template __value_type<_InputIterator> __t(*__first);
+ *__result = __t;
+ ++__result;
+ while (++__first != __last) {
+ if (!__pred(__t, *__first)) {
+ __t = *__first;
+ *__result = __t;
+ ++__result;
+ }
+ }
+ }
+ return pair<_InputIterator, _OutputIterator>(std::move(__first), std::move(__result));
+}
+
+template <class _AlgPolicy, class _BinaryPredicate, class _ForwardIterator, class _Sent, class _OutputIterator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pair<_ForwardIterator, _OutputIterator>
+__unique_copy(_ForwardIterator __first,
+ _Sent __last,
+ _OutputIterator __result,
+ _BinaryPredicate&& __pred,
+ __unique_copy_tags::__reread_from_input_tag) {
+ if (__first != __last) {
+ _ForwardIterator __i = __first;
+ *__result = *__i;
+ ++__result;
+ while (++__first != __last) {
+ if (!__pred(*__i, *__first)) {
+ *__result = *__first;
+ ++__result;
+ __i = __first;
+ }
+ }
+ }
+ return pair<_ForwardIterator, _OutputIterator>(std::move(__first), std::move(__result));
+}
+
+template <class _AlgPolicy, class _BinaryPredicate, class _InputIterator, class _Sent, class _InputAndOutputIterator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _InputAndOutputIterator>
+__unique_copy(_InputIterator __first,
+ _Sent __last,
+ _InputAndOutputIterator __result,
+ _BinaryPredicate&& __pred,
+ __unique_copy_tags::__reread_from_output_tag) {
+ if (__first != __last) {
+ *__result = *__first;
+ while (++__first != __last)
+ if (!__pred(*__result, *__first))
+ *++__result = *__first;
+ ++__result;
+ }
+ return pair<_InputIterator, _InputAndOutputIterator>(std::move(__first), std::move(__result));
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryPredicate>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred) {
+ using __algo_tag = __conditional_t<
+ is_base_of<forward_iterator_tag, typename iterator_traits<_InputIterator>::iterator_category>::value,
+ __unique_copy_tags::__reread_from_input_tag,
+ __conditional_t<
+ is_base_of<forward_iterator_tag, typename iterator_traits<_OutputIterator>::iterator_category>::value &&
+ is_same< typename iterator_traits<_InputIterator>::value_type,
+ typename iterator_traits<_OutputIterator>::value_type>::value,
+ __unique_copy_tags::__reread_from_output_tag,
+ __unique_copy_tags::__read_from_tmp_value_tag> >;
+ return std::__unique_copy<_ClassicAlgPolicy>(
+ std::move(__first), std::move(__last), std::move(__result), __pred, __algo_tag())
+ .second;
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
+ return std::unique_copy(std::move(__first), std::move(__last), std::move(__result), __equal_to());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_UNIQUE_COPY_H
diff --git a/libcxx/include/__cxx03/__algorithm/unwrap_iter.h b/libcxx/include/__cxx03/__algorithm/unwrap_iter.h
new file mode 100644
index 00000000000000..8cc0d22d4fc211
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/unwrap_iter.h
@@ -0,0 +1,85 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_UNWRAP_ITER_H
+#define _LIBCPP___ALGORITHM_UNWRAP_ITER_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/declval.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// TODO: Change the name of __unwrap_iter_impl to something more appropriate
+// The job of __unwrap_iter is to remove iterator wrappers (like reverse_iterator or __wrap_iter),
+// to reduce the number of template instantiations and to enable pointer-based optimizations e.g. in std::copy.
+//
+// Some algorithms (e.g. std::copy, but not std::sort) need to convert an
+// "unwrapped" result back into the original iterator type. Doing that is the job of __rewrap_iter.
+
+// Default case - we can't unwrap anything
+template <class _Iter, bool = __libcpp_is_contiguous_iterator<_Iter>::value>
+struct __unwrap_iter_impl {
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __rewrap(_Iter, _Iter __iter) { return __iter; }
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __unwrap(_Iter __i) _NOEXCEPT { return __i; }
+};
+
+// TODO(hardening): make sure that the following unwrapping doesn't unexpectedly turn hardened iterators into raw
+// pointers.
+
+// It's a contiguous iterator, so we can use a raw pointer instead
+template <class _Iter>
+struct __unwrap_iter_impl<_Iter, true> {
+ using _ToAddressT = decltype(std::__to_address(std::declval<_Iter>()));
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __rewrap(_Iter __orig_iter, _ToAddressT __unwrapped_iter) {
+ return __orig_iter + (__unwrapped_iter - std::__to_address(__orig_iter));
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToAddressT __unwrap(_Iter __i) _NOEXCEPT {
+ return std::__to_address(__i);
+ }
+};
+
+template <class _Iter,
+ class _Impl = __unwrap_iter_impl<_Iter>,
+ __enable_if_t<is_copy_constructible<_Iter>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 decltype(_Impl::__unwrap(std::declval<_Iter>()))
+__unwrap_iter(_Iter __i) _NOEXCEPT {
+ return _Impl::__unwrap(__i);
+}
+
+// Allow input_iterators to be passed to __unwrap_iter (but not __rewrap_iter)
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter, __enable_if_t<!is_copy_constructible<_Iter>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _Iter __unwrap_iter(_Iter __i) noexcept {
+ return __i;
+}
+#endif
+
+template <class _OrigIter, class _Iter, class _Impl = __unwrap_iter_impl<_OrigIter> >
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _OrigIter __rewrap_iter(_OrigIter __orig_iter, _Iter __iter) _NOEXCEPT {
+ return _Impl::__rewrap(std::move(__orig_iter), std::move(__iter));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_UNWRAP_ITER_H
diff --git a/libcxx/include/__cxx03/__algorithm/unwrap_range.h b/libcxx/include/__cxx03/__algorithm/unwrap_range.h
new file mode 100644
index 00000000000000..2d4b9bb5545ad3
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/unwrap_range.h
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_UNWRAP_RANGE_H
+#define _LIBCPP___ALGORITHM_UNWRAP_RANGE_H
+
+#include <__algorithm/unwrap_iter.h>
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/next.h>
+#include <__utility/declval.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// __unwrap_range and __rewrap_range are used to unwrap ranges which may have different iterator and sentinel types.
+// __unwrap_iter and __rewrap_iter don't work for this, because they assume that the iterator and sentinel have
+// the same type. __unwrap_range tries to get two iterators and then forward to __unwrap_iter.
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter, class _Sent>
+struct __unwrap_range_impl {
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __unwrap(_Iter __first, _Sent __sent)
+ requires random_access_iterator<_Iter> && sized_sentinel_for<_Sent, _Iter>
+ {
+ auto __last = ranges::next(__first, __sent);
+ return pair{std::__unwrap_iter(std::move(__first)), std::__unwrap_iter(std::move(__last))};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __unwrap(_Iter __first, _Sent __last) {
+ return pair{std::move(__first), std::move(__last)};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto
+ __rewrap(_Iter __orig_iter, decltype(std::__unwrap_iter(std::move(__orig_iter))) __iter)
+ requires random_access_iterator<_Iter> && sized_sentinel_for<_Sent, _Iter>
+ {
+ return std::__rewrap_iter(std::move(__orig_iter), std::move(__iter));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __rewrap(const _Iter&, _Iter __iter)
+ requires(!(random_access_iterator<_Iter> && sized_sentinel_for<_Sent, _Iter>))
+ {
+ return __iter;
+ }
+};
+
+template <class _Iter>
+struct __unwrap_range_impl<_Iter, _Iter> {
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __unwrap(_Iter __first, _Iter __last) {
+ return pair{std::__unwrap_iter(std::move(__first)), std::__unwrap_iter(std::move(__last))};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto
+ __rewrap(_Iter __orig_iter, decltype(std::__unwrap_iter(__orig_iter)) __iter) {
+ return std::__rewrap_iter(std::move(__orig_iter), std::move(__iter));
+ }
+};
+
+template <class _Iter, class _Sent>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __unwrap_range(_Iter __first, _Sent __last) {
+ return __unwrap_range_impl<_Iter, _Sent>::__unwrap(std::move(__first), std::move(__last));
+}
+
+template < class _Sent, class _Iter, class _Unwrapped>
+_LIBCPP_HIDE_FROM_ABI constexpr _Iter __rewrap_range(_Iter __orig_iter, _Unwrapped __iter) {
+ return __unwrap_range_impl<_Iter, _Sent>::__rewrap(std::move(__orig_iter), std::move(__iter));
+}
+#else // _LIBCPP_STD_VER >= 20
+template <class _Iter, class _Unwrapped = decltype(std::__unwrap_iter(std::declval<_Iter>()))>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR pair<_Unwrapped, _Unwrapped> __unwrap_range(_Iter __first, _Iter __last) {
+ return std::make_pair(std::__unwrap_iter(std::move(__first)), std::__unwrap_iter(std::move(__last)));
+}
+
+template <class _Iter, class _Unwrapped>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __rewrap_range(_Iter __orig_iter, _Unwrapped __iter) {
+ return std::__rewrap_iter(std::move(__orig_iter), std::move(__iter));
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_UNWRAP_RANGE_H
diff --git a/libcxx/include/__cxx03/__algorithm/upper_bound.h b/libcxx/include/__cxx03/__algorithm/upper_bound.h
new file mode 100644
index 00000000000000..c39dec2e896982
--- /dev/null
+++ b/libcxx/include/__cxx03/__algorithm/upper_bound.h
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_UPPER_BOUND_H
+#define _LIBCPP___ALGORITHM_UPPER_BOUND_H
+
+#include <__algorithm/comp.h>
+#include <__algorithm/half_positive.h>
+#include <__algorithm/iterator_operations.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/advance.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Compare, class _Iter, class _Sent, class _Tp, class _Proj>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter
+__upper_bound(_Iter __first, _Sent __last, const _Tp& __value, _Compare&& __comp, _Proj&& __proj) {
+ auto __len = _IterOps<_AlgPolicy>::distance(__first, __last);
+ while (__len != 0) {
+ auto __half_len = std::__half_positive(__len);
+ auto __mid = _IterOps<_AlgPolicy>::next(__first, __half_len);
+ if (std::__invoke(__comp, __value, std::__invoke(__proj, *__mid)))
+ __len = __half_len;
+ else {
+ __first = ++__mid;
+ __len -= __half_len + 1;
+ }
+ }
+ return __first;
+}
+
+template <class _ForwardIterator, class _Tp, class _Compare>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, _Compare __comp) {
+ static_assert(is_copy_constructible<_ForwardIterator>::value, "Iterator has to be copy constructible");
+ return std::__upper_bound<_ClassicAlgPolicy>(
+ std::move(__first), std::move(__last), __value, std::move(__comp), std::__identity());
+}
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ return std::upper_bound(std::move(__first), std::move(__last), __value, __less<>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_UPPER_BOUND_H
diff --git a/libcxx/include/__cxx03/__assert b/libcxx/include/__cxx03/__assert
new file mode 100644
index 00000000000000..49769fb4d44978
--- /dev/null
+++ b/libcxx/include/__cxx03/__assert
@@ -0,0 +1,118 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ASSERT
+#define _LIBCPP___ASSERT
+
+#include <__assertion_handler> // Note: this include is generated by CMake and is potentially vendor-provided.
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#define _LIBCPP_ASSERT(expression, message) \
+ (__builtin_expect(static_cast<bool>(expression), 1) \
+ ? (void)0 \
+ : _LIBCPP_ASSERTION_HANDLER(__FILE__ ":" _LIBCPP_TOSTRING(__LINE__) ": assertion " _LIBCPP_TOSTRING( \
+ expression) " failed: " message "\n"))
+
+// TODO: __builtin_assume can currently inhibit optimizations. Until this has been fixed and we can add
+// assumptions without a clear optimization intent, disable that to avoid worsening the code generation.
+// See https://discourse.llvm.org/t/llvm-assume-blocks-optimization/71609 for a discussion.
+#if 0 && __has_builtin(__builtin_assume)
+# define _LIBCPP_ASSUME(expression) \
+ (_LIBCPP_DIAGNOSTIC_PUSH _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wassume") \
+ __builtin_assume(static_cast<bool>(expression)) _LIBCPP_DIAGNOSTIC_POP)
+#else
+# define _LIBCPP_ASSUME(expression) ((void)0)
+#endif
+
+// clang-format off
+// Fast hardening mode checks.
+
+#if _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_FAST
+
+// Enabled checks.
+# define _LIBCPP_ASSERT_VALID_INPUT_RANGE(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(expression, message) _LIBCPP_ASSERT(expression, message)
+// Disabled checks.
+// On most modern platforms, dereferencing a null pointer does not lead to an actual memory access.
+# define _LIBCPP_ASSERT_NON_NULL(expression, message) _LIBCPP_ASSUME(expression)
+// Overlapping ranges will make algorithms produce incorrect results but don't directly lead to a security
+// vulnerability.
+# define _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_VALID_DEALLOCATION(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_PEDANTIC(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_INTERNAL(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_UNCATEGORIZED(expression, message) _LIBCPP_ASSUME(expression)
+
+// Extensive hardening mode checks.
+
+#elif _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_EXTENSIVE
+
+// Enabled checks.
+# define _LIBCPP_ASSERT_VALID_INPUT_RANGE(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_NON_NULL(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_VALID_DEALLOCATION(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_PEDANTIC(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_UNCATEGORIZED(expression, message) _LIBCPP_ASSERT(expression, message)
+// Disabled checks.
+# define _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_INTERNAL(expression, message) _LIBCPP_ASSUME(expression)
+
+// Debug hardening mode checks.
+
+#elif _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_DEBUG
+
+// All checks enabled.
+# define _LIBCPP_ASSERT_VALID_INPUT_RANGE(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_NON_NULL(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_VALID_DEALLOCATION(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_PEDANTIC(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_INTERNAL(expression, message) _LIBCPP_ASSERT(expression, message)
+# define _LIBCPP_ASSERT_UNCATEGORIZED(expression, message) _LIBCPP_ASSERT(expression, message)
+
+// Disable all checks if hardening is not enabled.
+
+#else
+
+// All checks disabled.
+# define _LIBCPP_ASSERT_VALID_INPUT_RANGE(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_NON_NULL(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_VALID_DEALLOCATION(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_PEDANTIC(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_INTERNAL(expression, message) _LIBCPP_ASSUME(expression)
+# define _LIBCPP_ASSERT_UNCATEGORIZED(expression, message) _LIBCPP_ASSUME(expression)
+
+#endif // _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_FAST
+// clang-format on
+
+#endif // _LIBCPP___ASSERT
diff --git a/libcxx/include/__cxx03/__atomic/aliases.h b/libcxx/include/__cxx03/__atomic/aliases.h
new file mode 100644
index 00000000000000..e27e09af6b77d9
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/aliases.h
@@ -0,0 +1,110 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_ALIASES_H
+#define _LIBCPP___ATOMIC_ALIASES_H
+
+#include <__atomic/atomic.h>
+#include <__atomic/atomic_lock_free.h>
+#include <__atomic/contention_t.h>
+#include <__atomic/is_always_lock_free.h>
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/make_unsigned.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using atomic_bool = atomic<bool>;
+using atomic_char = atomic<char>;
+using atomic_schar = atomic<signed char>;
+using atomic_uchar = atomic<unsigned char>;
+using atomic_short = atomic<short>;
+using atomic_ushort = atomic<unsigned short>;
+using atomic_int = atomic<int>;
+using atomic_uint = atomic<unsigned int>;
+using atomic_long = atomic<long>;
+using atomic_ulong = atomic<unsigned long>;
+using atomic_llong = atomic<long long>;
+using atomic_ullong = atomic<unsigned long long>;
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+using atomic_char8_t = atomic<char8_t>;
+#endif
+using atomic_char16_t = atomic<char16_t>;
+using atomic_char32_t = atomic<char32_t>;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using atomic_wchar_t = atomic<wchar_t>;
+#endif
+
+using atomic_int_least8_t = atomic<int_least8_t>;
+using atomic_uint_least8_t = atomic<uint_least8_t>;
+using atomic_int_least16_t = atomic<int_least16_t>;
+using atomic_uint_least16_t = atomic<uint_least16_t>;
+using atomic_int_least32_t = atomic<int_least32_t>;
+using atomic_uint_least32_t = atomic<uint_least32_t>;
+using atomic_int_least64_t = atomic<int_least64_t>;
+using atomic_uint_least64_t = atomic<uint_least64_t>;
+
+using atomic_int_fast8_t = atomic<int_fast8_t>;
+using atomic_uint_fast8_t = atomic<uint_fast8_t>;
+using atomic_int_fast16_t = atomic<int_fast16_t>;
+using atomic_uint_fast16_t = atomic<uint_fast16_t>;
+using atomic_int_fast32_t = atomic<int_fast32_t>;
+using atomic_uint_fast32_t = atomic<uint_fast32_t>;
+using atomic_int_fast64_t = atomic<int_fast64_t>;
+using atomic_uint_fast64_t = atomic<uint_fast64_t>;
+
+using atomic_int8_t = atomic< int8_t>;
+using atomic_uint8_t = atomic<uint8_t>;
+using atomic_int16_t = atomic< int16_t>;
+using atomic_uint16_t = atomic<uint16_t>;
+using atomic_int32_t = atomic< int32_t>;
+using atomic_uint32_t = atomic<uint32_t>;
+using atomic_int64_t = atomic< int64_t>;
+using atomic_uint64_t = atomic<uint64_t>;
+
+using atomic_intptr_t = atomic<intptr_t>;
+using atomic_uintptr_t = atomic<uintptr_t>;
+using atomic_size_t = atomic<size_t>;
+using atomic_ptrdiff_t = atomic<ptrdiff_t>;
+using atomic_intmax_t = atomic<intmax_t>;
+using atomic_uintmax_t = atomic<uintmax_t>;
+
+// C++20 atomic_{signed,unsigned}_lock_free: prefer the contention type most highly, then the largest lock-free type
+#if _LIBCPP_STD_VER >= 20
+# if ATOMIC_LLONG_LOCK_FREE == 2
+using __largest_lock_free_type = long long;
+# elif ATOMIC_INT_LOCK_FREE == 2
+using __largest_lock_free_type = int;
+# elif ATOMIC_SHORT_LOCK_FREE == 2
+using __largest_lock_free_type = short;
+# elif ATOMIC_CHAR_LOCK_FREE == 2
+using __largest_lock_free_type = char;
+# else
+# define _LIBCPP_NO_LOCK_FREE_TYPES // There are no lockfree types (this can happen on unusual platforms)
+# endif
+
+# ifndef _LIBCPP_NO_LOCK_FREE_TYPES
+using __contention_t_or_largest =
+ __conditional_t<__libcpp_is_always_lock_free<__cxx_contention_t>::__value,
+ __cxx_contention_t,
+ __largest_lock_free_type>;
+
+using atomic_signed_lock_free = atomic<__contention_t_or_largest>;
+using atomic_unsigned_lock_free = atomic<make_unsigned_t<__contention_t_or_largest>>;
+# endif // !_LIBCPP_NO_LOCK_FREE_TYPES
+#endif // C++20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_ALIASES_H
diff --git a/libcxx/include/__cxx03/__atomic/atomic.h b/libcxx/include/__cxx03/__atomic/atomic.h
new file mode 100644
index 00000000000000..bd3f659c22df01
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/atomic.h
@@ -0,0 +1,622 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_ATOMIC_H
+#define _LIBCPP___ATOMIC_ATOMIC_H
+
+#include <__atomic/atomic_base.h>
+#include <__atomic/check_memory_order.h>
+#include <__atomic/cxx_atomic_impl.h>
+#include <__atomic/memory_order.h>
+#include <__config>
+#include <__functional/operations.h>
+#include <__memory/addressof.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_pointer.h>
+#include <__type_traits/remove_volatile.h>
+#include <__utility/forward.h>
+#include <cstddef>
+#include <cstring>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct atomic : public __atomic_base<_Tp> {
+ using __base = __atomic_base<_Tp>;
+ using value_type = _Tp;
+ using difference_type = value_type;
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI atomic() = default;
+#else
+ _LIBCPP_HIDE_FROM_ABI atomic() _NOEXCEPT = default;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR atomic(_Tp __d) _NOEXCEPT : __base(__d) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator=(_Tp __d) volatile _NOEXCEPT {
+ __base::store(__d);
+ return __d;
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator=(_Tp __d) _NOEXCEPT {
+ __base::store(__d);
+ return __d;
+ }
+
+ atomic& operator=(const atomic&) = delete;
+ atomic& operator=(const atomic&) volatile = delete;
+};
+
+// atomic<T*>
+
+template <class _Tp>
+struct atomic<_Tp*> : public __atomic_base<_Tp*> {
+ using __base = __atomic_base<_Tp*>;
+ using value_type = _Tp*;
+ using difference_type = ptrdiff_t;
+
+ _LIBCPP_HIDE_FROM_ABI atomic() _NOEXCEPT = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR atomic(_Tp* __d) _NOEXCEPT : __base(__d) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator=(_Tp* __d) volatile _NOEXCEPT {
+ __base::store(__d);
+ return __d;
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator=(_Tp* __d) _NOEXCEPT {
+ __base::store(__d);
+ return __d;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* fetch_add(ptrdiff_t __op, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ // __atomic_fetch_add accepts function pointers, guard against them.
+ static_assert(!is_function<__remove_pointer_t<_Tp> >::value, "Pointer to function isn't allowed");
+ return std::__cxx_atomic_fetch_add(std::addressof(this->__a_), __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* fetch_add(ptrdiff_t __op, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ // __atomic_fetch_add accepts function pointers, guard against them.
+ static_assert(!is_function<__remove_pointer_t<_Tp> >::value, "Pointer to function isn't allowed");
+ return std::__cxx_atomic_fetch_add(std::addressof(this->__a_), __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* fetch_sub(ptrdiff_t __op, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ // __atomic_fetch_add accepts function pointers, guard against them.
+ static_assert(!is_function<__remove_pointer_t<_Tp> >::value, "Pointer to function isn't allowed");
+ return std::__cxx_atomic_fetch_sub(std::addressof(this->__a_), __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* fetch_sub(ptrdiff_t __op, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ // __atomic_fetch_add accepts function pointers, guard against them.
+ static_assert(!is_function<__remove_pointer_t<_Tp> >::value, "Pointer to function isn't allowed");
+ return std::__cxx_atomic_fetch_sub(std::addressof(this->__a_), __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator++(int) volatile _NOEXCEPT { return fetch_add(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator++(int) _NOEXCEPT { return fetch_add(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator--(int) volatile _NOEXCEPT { return fetch_sub(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator--(int) _NOEXCEPT { return fetch_sub(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator++() volatile _NOEXCEPT { return fetch_add(1) + 1; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator++() _NOEXCEPT { return fetch_add(1) + 1; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator--() volatile _NOEXCEPT { return fetch_sub(1) - 1; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator--() _NOEXCEPT { return fetch_sub(1) - 1; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator+=(ptrdiff_t __op) volatile _NOEXCEPT { return fetch_add(__op) + __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator+=(ptrdiff_t __op) _NOEXCEPT { return fetch_add(__op) + __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator-=(ptrdiff_t __op) volatile _NOEXCEPT { return fetch_sub(__op) - __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator-=(ptrdiff_t __op) _NOEXCEPT { return fetch_sub(__op) - __op; }
+
+ atomic& operator=(const atomic&) = delete;
+ atomic& operator=(const atomic&) volatile = delete;
+};
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+ requires is_floating_point_v<_Tp>
+struct atomic<_Tp> : __atomic_base<_Tp> {
+private:
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __is_fp80_long_double() {
+ // Only x87-fp80 long double has 64-bit mantissa
+ return __LDBL_MANT_DIG__ == 64 && std::is_same_v<_Tp, long double>;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __has_rmw_builtin() {
+# ifndef _LIBCPP_COMPILER_CLANG_BASED
+ return false;
+# else
+ // The builtin __cxx_atomic_fetch_add errors during compilation for
+ // long double on platforms with fp80 format.
+ // For more details, see
+ // lib/Sema/SemaChecking.cpp function IsAllowedValueType
+ // LLVM Parser does not allow atomicrmw with x86_fp80 type.
+ // if (ValType->isSpecificBuiltinType(BuiltinType::LongDouble) &&
+ // &Context.getTargetInfo().getLongDoubleFormat() ==
+ // &llvm::APFloat::x87DoubleExtended())
+ // For more info
+ // https://github.com/llvm/llvm-project/issues/68602
+ // https://reviews.llvm.org/D53965
+ return !__is_fp80_long_double();
+# endif
+ }
+
+ template <class _This, class _Operation, class _BuiltinOp>
+ _LIBCPP_HIDE_FROM_ABI static _Tp
+ __rmw_op(_This&& __self, _Tp __operand, memory_order __m, _Operation __operation, _BuiltinOp __builtin_op) {
+ if constexpr (__has_rmw_builtin()) {
+ return __builtin_op(std::addressof(std::forward<_This>(__self).__a_), __operand, __m);
+ } else {
+ _Tp __old = __self.load(memory_order_relaxed);
+ _Tp __new = __operation(__old, __operand);
+ while (!__self.compare_exchange_weak(__old, __new, __m, memory_order_relaxed)) {
+# ifdef _LIBCPP_COMPILER_CLANG_BASED
+ if constexpr (__is_fp80_long_double()) {
+ // https://github.com/llvm/llvm-project/issues/47978
+ // clang bug: __old is not updated on failure for atomic<long double>::compare_exchange_weak
+ // Note __old = __self.load(memory_order_relaxed) will not work
+ std::__cxx_atomic_load_inplace(std::addressof(__self.__a_), &__old, memory_order_relaxed);
+ }
+# endif
+ __new = __operation(__old, __operand);
+ }
+ return __old;
+ }
+ }
+
+ template <class _This>
+ _LIBCPP_HIDE_FROM_ABI static _Tp __fetch_add(_This&& __self, _Tp __operand, memory_order __m) {
+ auto __builtin_op = [](auto __a, auto __builtin_operand, auto __order) {
+ return std::__cxx_atomic_fetch_add(__a, __builtin_operand, __order);
+ };
+ return __rmw_op(std::forward<_This>(__self), __operand, __m, std::plus<>{}, __builtin_op);
+ }
+
+ template <class _This>
+ _LIBCPP_HIDE_FROM_ABI static _Tp __fetch_sub(_This&& __self, _Tp __operand, memory_order __m) {
+ auto __builtin_op = [](auto __a, auto __builtin_operand, auto __order) {
+ return std::__cxx_atomic_fetch_sub(__a, __builtin_operand, __order);
+ };
+ return __rmw_op(std::forward<_This>(__self), __operand, __m, std::minus<>{}, __builtin_op);
+ }
+
+public:
+ using __base = __atomic_base<_Tp>;
+ using value_type = _Tp;
+ using difference_type = value_type;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr atomic() noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr atomic(_Tp __d) noexcept : __base(__d) {}
+
+ atomic(const atomic&) = delete;
+ atomic& operator=(const atomic&) = delete;
+ atomic& operator=(const atomic&) volatile = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator=(_Tp __d) volatile noexcept
+ requires __base::is_always_lock_free
+ {
+ __base::store(__d);
+ return __d;
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator=(_Tp __d) noexcept {
+ __base::store(__d);
+ return __d;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_add(_Tp __op, memory_order __m = memory_order_seq_cst) volatile noexcept
+ requires __base::is_always_lock_free
+ {
+ return __fetch_add(*this, __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_add(_Tp __op, memory_order __m = memory_order_seq_cst) noexcept {
+ return __fetch_add(*this, __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_sub(_Tp __op, memory_order __m = memory_order_seq_cst) volatile noexcept
+ requires __base::is_always_lock_free
+ {
+ return __fetch_sub(*this, __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_sub(_Tp __op, memory_order __m = memory_order_seq_cst) noexcept {
+ return __fetch_sub(*this, __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator+=(_Tp __op) volatile noexcept
+ requires __base::is_always_lock_free
+ {
+ return fetch_add(__op) + __op;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator+=(_Tp __op) noexcept { return fetch_add(__op) + __op; }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator-=(_Tp __op) volatile noexcept
+ requires __base::is_always_lock_free
+ {
+ return fetch_sub(__op) - __op;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator-=(_Tp __op) noexcept { return fetch_sub(__op) - __op; }
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+// atomic_is_lock_free
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_is_lock_free(const volatile atomic<_Tp>* __o) _NOEXCEPT {
+ return __o->is_lock_free();
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_is_lock_free(const atomic<_Tp>* __o) _NOEXCEPT {
+ return __o->is_lock_free();
+}
+
+// atomic_init
+
+template <class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_HIDE_FROM_ABI void
+atomic_init(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ std::__cxx_atomic_init(std::addressof(__o->__a_), __d);
+}
+
+template <class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_HIDE_FROM_ABI void
+atomic_init(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ std::__cxx_atomic_init(std::addressof(__o->__a_), __d);
+}
+
+// atomic_store
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void atomic_store(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ __o->store(__d);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void atomic_store(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ __o->store(__d);
+}
+
+// atomic_store_explicit
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+atomic_store_explicit(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d, memory_order __m) _NOEXCEPT
+ _LIBCPP_CHECK_STORE_MEMORY_ORDER(__m) {
+ __o->store(__d, __m);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+atomic_store_explicit(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d, memory_order __m) _NOEXCEPT
+ _LIBCPP_CHECK_STORE_MEMORY_ORDER(__m) {
+ __o->store(__d, __m);
+}
+
+// atomic_load
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_load(const volatile atomic<_Tp>* __o) _NOEXCEPT {
+ return __o->load();
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_load(const atomic<_Tp>* __o) _NOEXCEPT {
+ return __o->load();
+}
+
+// atomic_load_explicit
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_load_explicit(const volatile atomic<_Tp>* __o, memory_order __m) _NOEXCEPT
+ _LIBCPP_CHECK_LOAD_MEMORY_ORDER(__m) {
+ return __o->load(__m);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_load_explicit(const atomic<_Tp>* __o, memory_order __m) _NOEXCEPT
+ _LIBCPP_CHECK_LOAD_MEMORY_ORDER(__m) {
+ return __o->load(__m);
+}
+
+// atomic_exchange
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_exchange(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ return __o->exchange(__d);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_exchange(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ return __o->exchange(__d);
+}
+
+// atomic_exchange_explicit
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_exchange_explicit(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d, memory_order __m) _NOEXCEPT {
+ return __o->exchange(__d, __m);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_exchange_explicit(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __d, memory_order __m) _NOEXCEPT {
+ return __o->exchange(__d, __m);
+}
+
+// atomic_compare_exchange_weak
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_weak(
+ volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type* __e, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ return __o->compare_exchange_weak(*__e, __d);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_weak(
+ atomic<_Tp>* __o, typename atomic<_Tp>::value_type* __e, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ return __o->compare_exchange_weak(*__e, __d);
+}
+
+// atomic_compare_exchange_strong
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_strong(
+ volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type* __e, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ return __o->compare_exchange_strong(*__e, __d);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_strong(
+ atomic<_Tp>* __o, typename atomic<_Tp>::value_type* __e, typename atomic<_Tp>::value_type __d) _NOEXCEPT {
+ return __o->compare_exchange_strong(*__e, __d);
+}
+
+// atomic_compare_exchange_weak_explicit
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_weak_explicit(
+ volatile atomic<_Tp>* __o,
+ typename atomic<_Tp>::value_type* __e,
+ typename atomic<_Tp>::value_type __d,
+ memory_order __s,
+ memory_order __f) _NOEXCEPT _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__s, __f) {
+ return __o->compare_exchange_weak(*__e, __d, __s, __f);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_weak_explicit(
+ atomic<_Tp>* __o,
+ typename atomic<_Tp>::value_type* __e,
+ typename atomic<_Tp>::value_type __d,
+ memory_order __s,
+ memory_order __f) _NOEXCEPT _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__s, __f) {
+ return __o->compare_exchange_weak(*__e, __d, __s, __f);
+}
+
+// atomic_compare_exchange_strong_explicit
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_strong_explicit(
+ volatile atomic<_Tp>* __o,
+ typename atomic<_Tp>::value_type* __e,
+ typename atomic<_Tp>::value_type __d,
+ memory_order __s,
+ memory_order __f) _NOEXCEPT _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__s, __f) {
+ return __o->compare_exchange_strong(*__e, __d, __s, __f);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_strong_explicit(
+ atomic<_Tp>* __o,
+ typename atomic<_Tp>::value_type* __e,
+ typename atomic<_Tp>::value_type __d,
+ memory_order __s,
+ memory_order __f) _NOEXCEPT _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__s, __f) {
+ return __o->compare_exchange_strong(*__e, __d, __s, __f);
+}
+
+// atomic_wait
+
+template <class _Tp>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+atomic_wait(const volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __v) _NOEXCEPT {
+ return __o->wait(__v);
+}
+
+template <class _Tp>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+atomic_wait(const atomic<_Tp>* __o, typename atomic<_Tp>::value_type __v) _NOEXCEPT {
+ return __o->wait(__v);
+}
+
+// atomic_wait_explicit
+
+template <class _Tp>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+atomic_wait_explicit(const volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __v, memory_order __m) _NOEXCEPT
+ _LIBCPP_CHECK_LOAD_MEMORY_ORDER(__m) {
+ return __o->wait(__v, __m);
+}
+
+template <class _Tp>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+atomic_wait_explicit(const atomic<_Tp>* __o, typename atomic<_Tp>::value_type __v, memory_order __m) _NOEXCEPT
+ _LIBCPP_CHECK_LOAD_MEMORY_ORDER(__m) {
+ return __o->wait(__v, __m);
+}
+
+// atomic_notify_one
+
+template <class _Tp>
+_LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+atomic_notify_one(volatile atomic<_Tp>* __o) _NOEXCEPT {
+ __o->notify_one();
+}
+template <class _Tp>
+_LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+atomic_notify_one(atomic<_Tp>* __o) _NOEXCEPT {
+ __o->notify_one();
+}
+
+// atomic_notify_all
+
+template <class _Tp>
+_LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+atomic_notify_all(volatile atomic<_Tp>* __o) _NOEXCEPT {
+ __o->notify_all();
+}
+template <class _Tp>
+_LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+atomic_notify_all(atomic<_Tp>* __o) _NOEXCEPT {
+ __o->notify_all();
+}
+
+// atomic_fetch_add
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_fetch_add(volatile atomic<_Tp>* __o, typename atomic<_Tp>::difference_type __op) _NOEXCEPT {
+ return __o->fetch_add(__op);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_add(atomic<_Tp>* __o, typename atomic<_Tp>::difference_type __op) _NOEXCEPT {
+ return __o->fetch_add(__op);
+}
+
+// atomic_fetch_add_explicit
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_add_explicit(
+ volatile atomic<_Tp>* __o, typename atomic<_Tp>::difference_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_add(__op, __m);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_fetch_add_explicit(atomic<_Tp>* __o, typename atomic<_Tp>::difference_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_add(__op, __m);
+}
+
+// atomic_fetch_sub
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_fetch_sub(volatile atomic<_Tp>* __o, typename atomic<_Tp>::difference_type __op) _NOEXCEPT {
+ return __o->fetch_sub(__op);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_sub(atomic<_Tp>* __o, typename atomic<_Tp>::difference_type __op) _NOEXCEPT {
+ return __o->fetch_sub(__op);
+}
+
+// atomic_fetch_sub_explicit
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_sub_explicit(
+ volatile atomic<_Tp>* __o, typename atomic<_Tp>::difference_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_sub(__op, __m);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_fetch_sub_explicit(atomic<_Tp>* __o, typename atomic<_Tp>::difference_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_sub(__op, __m);
+}
+
+// atomic_fetch_and
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_and(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op) _NOEXCEPT {
+ return __o->fetch_and(__op);
+}
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_and(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op) _NOEXCEPT {
+ return __o->fetch_and(__op);
+}
+
+// atomic_fetch_and_explicit
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_and_explicit(
+ volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_and(__op, __m);
+}
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_fetch_and_explicit(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_and(__op, __m);
+}
+
+// atomic_fetch_or
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_or(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op) _NOEXCEPT {
+ return __o->fetch_or(__op);
+}
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_or(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op) _NOEXCEPT {
+ return __o->fetch_or(__op);
+}
+
+// atomic_fetch_or_explicit
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_fetch_or_explicit(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_or(__op, __m);
+}
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_fetch_or_explicit(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_or(__op, __m);
+}
+
+// atomic_fetch_xor
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_xor(volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op) _NOEXCEPT {
+ return __o->fetch_xor(__op);
+}
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_xor(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op) _NOEXCEPT {
+ return __o->fetch_xor(__op);
+}
+
+// atomic_fetch_xor_explicit
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp atomic_fetch_xor_explicit(
+ volatile atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_xor(__op, __m);
+}
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value && !is_same<_Tp, bool>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp
+atomic_fetch_xor_explicit(atomic<_Tp>* __o, typename atomic<_Tp>::value_type __op, memory_order __m) _NOEXCEPT {
+ return __o->fetch_xor(__op, __m);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_ATOMIC_H
diff --git a/libcxx/include/__cxx03/__atomic/atomic_base.h b/libcxx/include/__cxx03/__atomic/atomic_base.h
new file mode 100644
index 00000000000000..7e26434c9c3a0a
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/atomic_base.h
@@ -0,0 +1,221 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_ATOMIC_BASE_H
+#define _LIBCPP___ATOMIC_ATOMIC_BASE_H
+
+#include <__atomic/atomic_sync.h>
+#include <__atomic/check_memory_order.h>
+#include <__atomic/cxx_atomic_impl.h>
+#include <__atomic/is_always_lock_free.h>
+#include <__atomic/memory_order.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_same.h>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, bool = is_integral<_Tp>::value && !is_same<_Tp, bool>::value>
+struct __atomic_base // false
+{
+ mutable __cxx_atomic_impl<_Tp> __a_;
+
+#if _LIBCPP_STD_VER >= 17
+ static constexpr bool is_always_lock_free = __libcpp_is_always_lock_free<__cxx_atomic_impl<_Tp> >::__value;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI bool is_lock_free() const volatile _NOEXCEPT {
+ return __cxx_atomic_is_lock_free(sizeof(__cxx_atomic_impl<_Tp>));
+ }
+ _LIBCPP_HIDE_FROM_ABI bool is_lock_free() const _NOEXCEPT {
+ return static_cast<__atomic_base const volatile*>(this)->is_lock_free();
+ }
+ _LIBCPP_HIDE_FROM_ABI void store(_Tp __d, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT
+ _LIBCPP_CHECK_STORE_MEMORY_ORDER(__m) {
+ std::__cxx_atomic_store(std::addressof(__a_), __d, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI void store(_Tp __d, memory_order __m = memory_order_seq_cst) _NOEXCEPT
+ _LIBCPP_CHECK_STORE_MEMORY_ORDER(__m) {
+ std::__cxx_atomic_store(std::addressof(__a_), __d, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp load(memory_order __m = memory_order_seq_cst) const volatile _NOEXCEPT
+ _LIBCPP_CHECK_LOAD_MEMORY_ORDER(__m) {
+ return std::__cxx_atomic_load(std::addressof(__a_), __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp load(memory_order __m = memory_order_seq_cst) const _NOEXCEPT
+ _LIBCPP_CHECK_LOAD_MEMORY_ORDER(__m) {
+ return std::__cxx_atomic_load(std::addressof(__a_), __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI operator _Tp() const volatile _NOEXCEPT { return load(); }
+ _LIBCPP_HIDE_FROM_ABI operator _Tp() const _NOEXCEPT { return load(); }
+ _LIBCPP_HIDE_FROM_ABI _Tp exchange(_Tp __d, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return std::__cxx_atomic_exchange(std::addressof(__a_), __d, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp exchange(_Tp __d, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return std::__cxx_atomic_exchange(std::addressof(__a_), __d, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_weak(_Tp& __e, _Tp __d, memory_order __s, memory_order __f) volatile _NOEXCEPT
+ _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__s, __f) {
+ return std::__cxx_atomic_compare_exchange_weak(std::addressof(__a_), std::addressof(__e), __d, __s, __f);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool compare_exchange_weak(_Tp& __e, _Tp __d, memory_order __s, memory_order __f) _NOEXCEPT
+ _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__s, __f) {
+ return std::__cxx_atomic_compare_exchange_weak(std::addressof(__a_), std::addressof(__e), __d, __s, __f);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_strong(_Tp& __e, _Tp __d, memory_order __s, memory_order __f) volatile _NOEXCEPT
+ _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__s, __f) {
+ return std::__cxx_atomic_compare_exchange_strong(std::addressof(__a_), std::addressof(__e), __d, __s, __f);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool compare_exchange_strong(_Tp& __e, _Tp __d, memory_order __s, memory_order __f) _NOEXCEPT
+ _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__s, __f) {
+ return std::__cxx_atomic_compare_exchange_strong(std::addressof(__a_), std::addressof(__e), __d, __s, __f);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_weak(_Tp& __e, _Tp __d, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return std::__cxx_atomic_compare_exchange_weak(std::addressof(__a_), std::addressof(__e), __d, __m, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_weak(_Tp& __e, _Tp __d, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return std::__cxx_atomic_compare_exchange_weak(std::addressof(__a_), std::addressof(__e), __d, __m, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_strong(_Tp& __e, _Tp __d, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return std::__cxx_atomic_compare_exchange_strong(std::addressof(__a_), std::addressof(__e), __d, __m, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_strong(_Tp& __e, _Tp __d, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return std::__cxx_atomic_compare_exchange_strong(std::addressof(__a_), std::addressof(__e), __d, __m, __m);
+ }
+
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void wait(_Tp __v, memory_order __m = memory_order_seq_cst) const
+ volatile _NOEXCEPT {
+ std::__atomic_wait(*this, __v, __m);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+ wait(_Tp __v, memory_order __m = memory_order_seq_cst) const _NOEXCEPT {
+ std::__atomic_wait(*this, __v, __m);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void notify_one() volatile _NOEXCEPT {
+ std::__atomic_notify_one(*this);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void notify_one() _NOEXCEPT { std::__atomic_notify_one(*this); }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void notify_all() volatile _NOEXCEPT {
+ std::__atomic_notify_all(*this);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void notify_all() _NOEXCEPT { std::__atomic_notify_all(*this); }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr __atomic_base() noexcept(is_nothrow_default_constructible_v<_Tp>) : __a_(_Tp()) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI __atomic_base() _NOEXCEPT = default;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __atomic_base(_Tp __d) _NOEXCEPT : __a_(__d) {}
+
+ __atomic_base(const __atomic_base&) = delete;
+};
+
+// atomic<Integral>
+
+template <class _Tp>
+struct __atomic_base<_Tp, true> : public __atomic_base<_Tp, false> {
+ using __base = __atomic_base<_Tp, false>;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __atomic_base() _NOEXCEPT = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __atomic_base(_Tp __d) _NOEXCEPT : __base(__d) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_add(_Tp __op, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return std::__cxx_atomic_fetch_add(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_add(_Tp __op, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return std::__cxx_atomic_fetch_add(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_sub(_Tp __op, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return std::__cxx_atomic_fetch_sub(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_sub(_Tp __op, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return std::__cxx_atomic_fetch_sub(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_and(_Tp __op, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return std::__cxx_atomic_fetch_and(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_and(_Tp __op, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return std::__cxx_atomic_fetch_and(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_or(_Tp __op, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return std::__cxx_atomic_fetch_or(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_or(_Tp __op, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return std::__cxx_atomic_fetch_or(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_xor(_Tp __op, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return std::__cxx_atomic_fetch_xor(std::addressof(this->__a_), __op, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_xor(_Tp __op, memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return std::__cxx_atomic_fetch_xor(std::addressof(this->__a_), __op, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator++(int) volatile _NOEXCEPT { return fetch_add(_Tp(1)); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator++(int) _NOEXCEPT { return fetch_add(_Tp(1)); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator--(int) volatile _NOEXCEPT { return fetch_sub(_Tp(1)); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator--(int) _NOEXCEPT { return fetch_sub(_Tp(1)); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator++() volatile _NOEXCEPT { return fetch_add(_Tp(1)) + _Tp(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator++() _NOEXCEPT { return fetch_add(_Tp(1)) + _Tp(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator--() volatile _NOEXCEPT { return fetch_sub(_Tp(1)) - _Tp(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator--() _NOEXCEPT { return fetch_sub(_Tp(1)) - _Tp(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator+=(_Tp __op) volatile _NOEXCEPT { return fetch_add(__op) + __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator+=(_Tp __op) _NOEXCEPT { return fetch_add(__op) + __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator-=(_Tp __op) volatile _NOEXCEPT { return fetch_sub(__op) - __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator-=(_Tp __op) _NOEXCEPT { return fetch_sub(__op) - __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator&=(_Tp __op) volatile _NOEXCEPT { return fetch_and(__op) & __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator&=(_Tp __op) _NOEXCEPT { return fetch_and(__op) & __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator|=(_Tp __op) volatile _NOEXCEPT { return fetch_or(__op) | __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator|=(_Tp __op) _NOEXCEPT { return fetch_or(__op) | __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator^=(_Tp __op) volatile _NOEXCEPT { return fetch_xor(__op) ^ __op; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator^=(_Tp __op) _NOEXCEPT { return fetch_xor(__op) ^ __op; }
+};
+
+// Here we need _IsIntegral because the default template argument is not enough
+// e.g __atomic_base<int> is __atomic_base<int, true>, which inherits from
+// __atomic_base<int, false> and the caller of the wait function is
+// __atomic_base<int, false>. So specializing __atomic_base<_Tp> does not work
+template <class _Tp, bool _IsIntegral>
+struct __atomic_waitable_traits<__atomic_base<_Tp, _IsIntegral> > {
+ static _LIBCPP_HIDE_FROM_ABI _Tp __atomic_load(const __atomic_base<_Tp, _IsIntegral>& __a, memory_order __order) {
+ return __a.load(__order);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _Tp
+ __atomic_load(const volatile __atomic_base<_Tp, _IsIntegral>& __this, memory_order __order) {
+ return __this.load(__order);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI const __cxx_atomic_impl<_Tp>*
+ __atomic_contention_address(const __atomic_base<_Tp, _IsIntegral>& __a) {
+ return std::addressof(__a.__a_);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI const volatile __cxx_atomic_impl<_Tp>*
+ __atomic_contention_address(const volatile __atomic_base<_Tp, _IsIntegral>& __this) {
+ return std::addressof(__this.__a_);
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_ATOMIC_BASE_H
diff --git a/libcxx/include/__cxx03/__atomic/atomic_flag.h b/libcxx/include/__cxx03/__atomic/atomic_flag.h
new file mode 100644
index 00000000000000..00b157cdff78b7
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/atomic_flag.h
@@ -0,0 +1,189 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_ATOMIC_FLAG_H
+#define _LIBCPP___ATOMIC_ATOMIC_FLAG_H
+
+#include <__atomic/atomic_sync.h>
+#include <__atomic/contention_t.h>
+#include <__atomic/cxx_atomic_impl.h>
+#include <__atomic/memory_order.h>
+#include <__chrono/duration.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__thread/support.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct atomic_flag {
+ __cxx_atomic_impl<_LIBCPP_ATOMIC_FLAG_TYPE> __a_;
+
+ _LIBCPP_HIDE_FROM_ABI bool test(memory_order __m = memory_order_seq_cst) const volatile _NOEXCEPT {
+ return _LIBCPP_ATOMIC_FLAG_TYPE(true) == __cxx_atomic_load(&__a_, __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool test(memory_order __m = memory_order_seq_cst) const _NOEXCEPT {
+ return _LIBCPP_ATOMIC_FLAG_TYPE(true) == __cxx_atomic_load(&__a_, __m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool test_and_set(memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ return __cxx_atomic_exchange(&__a_, _LIBCPP_ATOMIC_FLAG_TYPE(true), __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool test_and_set(memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ return __cxx_atomic_exchange(&__a_, _LIBCPP_ATOMIC_FLAG_TYPE(true), __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear(memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT {
+ __cxx_atomic_store(&__a_, _LIBCPP_ATOMIC_FLAG_TYPE(false), __m);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear(memory_order __m = memory_order_seq_cst) _NOEXCEPT {
+ __cxx_atomic_store(&__a_, _LIBCPP_ATOMIC_FLAG_TYPE(false), __m);
+ }
+
+ _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+ wait(bool __v, memory_order __m = memory_order_seq_cst) const volatile _NOEXCEPT {
+ std::__atomic_wait(*this, _LIBCPP_ATOMIC_FLAG_TYPE(__v), __m);
+ }
+ _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+ wait(bool __v, memory_order __m = memory_order_seq_cst) const _NOEXCEPT {
+ std::__atomic_wait(*this, _LIBCPP_ATOMIC_FLAG_TYPE(__v), __m);
+ }
+ _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void notify_one() volatile _NOEXCEPT {
+ std::__atomic_notify_one(*this);
+ }
+ _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void notify_one() _NOEXCEPT {
+ std::__atomic_notify_one(*this);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void notify_all() volatile _NOEXCEPT {
+ std::__atomic_notify_all(*this);
+ }
+ _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void notify_all() _NOEXCEPT {
+ std::__atomic_notify_all(*this);
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr atomic_flag() _NOEXCEPT : __a_(false) {}
+#else
+ atomic_flag() _NOEXCEPT = default;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR atomic_flag(bool __b) _NOEXCEPT : __a_(__b) {} // EXTENSION
+
+ atomic_flag(const atomic_flag&) = delete;
+ atomic_flag& operator=(const atomic_flag&) = delete;
+ atomic_flag& operator=(const atomic_flag&) volatile = delete;
+};
+
+template <>
+struct __atomic_waitable_traits<atomic_flag> {
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_ATOMIC_FLAG_TYPE __atomic_load(const atomic_flag& __a, memory_order __order) {
+ return std::__cxx_atomic_load(&__a.__a_, __order);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_ATOMIC_FLAG_TYPE
+ __atomic_load(const volatile atomic_flag& __a, memory_order __order) {
+ return std::__cxx_atomic_load(&__a.__a_, __order);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI const __cxx_atomic_impl<_LIBCPP_ATOMIC_FLAG_TYPE>*
+ __atomic_contention_address(const atomic_flag& __a) {
+ return std::addressof(__a.__a_);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI const volatile __cxx_atomic_impl<_LIBCPP_ATOMIC_FLAG_TYPE>*
+ __atomic_contention_address(const volatile atomic_flag& __a) {
+ return std::addressof(__a.__a_);
+ }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_flag_test(const volatile atomic_flag* __o) _NOEXCEPT { return __o->test(); }
+
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_flag_test(const atomic_flag* __o) _NOEXCEPT { return __o->test(); }
+
+inline _LIBCPP_HIDE_FROM_ABI bool
+atomic_flag_test_explicit(const volatile atomic_flag* __o, memory_order __m) _NOEXCEPT {
+ return __o->test(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_flag_test_explicit(const atomic_flag* __o, memory_order __m) _NOEXCEPT {
+ return __o->test(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_flag_test_and_set(volatile atomic_flag* __o) _NOEXCEPT {
+ return __o->test_and_set();
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_flag_test_and_set(atomic_flag* __o) _NOEXCEPT { return __o->test_and_set(); }
+
+inline _LIBCPP_HIDE_FROM_ABI bool
+atomic_flag_test_and_set_explicit(volatile atomic_flag* __o, memory_order __m) _NOEXCEPT {
+ return __o->test_and_set(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_flag_test_and_set_explicit(atomic_flag* __o, memory_order __m) _NOEXCEPT {
+ return __o->test_and_set(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void atomic_flag_clear(volatile atomic_flag* __o) _NOEXCEPT { __o->clear(); }
+
+inline _LIBCPP_HIDE_FROM_ABI void atomic_flag_clear(atomic_flag* __o) _NOEXCEPT { __o->clear(); }
+
+inline _LIBCPP_HIDE_FROM_ABI void atomic_flag_clear_explicit(volatile atomic_flag* __o, memory_order __m) _NOEXCEPT {
+ __o->clear(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void atomic_flag_clear_explicit(atomic_flag* __o, memory_order __m) _NOEXCEPT {
+ __o->clear(__m);
+}
+
+inline _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_SYNC void
+atomic_flag_wait(const volatile atomic_flag* __o, bool __v) _NOEXCEPT {
+ __o->wait(__v);
+}
+
+inline _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_SYNC void
+atomic_flag_wait(const atomic_flag* __o, bool __v) _NOEXCEPT {
+ __o->wait(__v);
+}
+
+inline _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_SYNC void
+atomic_flag_wait_explicit(const volatile atomic_flag* __o, bool __v, memory_order __m) _NOEXCEPT {
+ __o->wait(__v, __m);
+}
+
+inline _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_SYNC void
+atomic_flag_wait_explicit(const atomic_flag* __o, bool __v, memory_order __m) _NOEXCEPT {
+ __o->wait(__v, __m);
+}
+
+inline _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_SYNC void
+atomic_flag_notify_one(volatile atomic_flag* __o) _NOEXCEPT {
+ __o->notify_one();
+}
+
+inline _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_SYNC void
+atomic_flag_notify_one(atomic_flag* __o) _NOEXCEPT {
+ __o->notify_one();
+}
+
+inline _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_SYNC void
+atomic_flag_notify_all(volatile atomic_flag* __o) _NOEXCEPT {
+ __o->notify_all();
+}
+
+inline _LIBCPP_DEPRECATED_ATOMIC_SYNC _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_SYNC void
+atomic_flag_notify_all(atomic_flag* __o) _NOEXCEPT {
+ __o->notify_all();
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_ATOMIC_FLAG_H
diff --git a/libcxx/include/__cxx03/__atomic/atomic_init.h b/libcxx/include/__cxx03/__atomic/atomic_init.h
new file mode 100644
index 00000000000000..8e86ba31b4ac3b
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/atomic_init.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_ATOMIC_INIT_H
+#define _LIBCPP___ATOMIC_ATOMIC_INIT_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#define ATOMIC_FLAG_INIT {false}
+#define ATOMIC_VAR_INIT(__v) {__v}
+
+#if _LIBCPP_STD_VER >= 20 && defined(_LIBCPP_COMPILER_CLANG_BASED) && !defined(_LIBCPP_DISABLE_DEPRECATION_WARNINGS)
+# pragma clang deprecated(ATOMIC_VAR_INIT)
+#endif
+
+#endif // _LIBCPP___ATOMIC_ATOMIC_INIT_H
diff --git a/libcxx/include/__cxx03/__atomic/atomic_lock_free.h b/libcxx/include/__cxx03/__atomic/atomic_lock_free.h
new file mode 100644
index 00000000000000..0715439db45039
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/atomic_lock_free.h
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_ATOMIC_LOCK_FREE_H
+#define _LIBCPP___ATOMIC_ATOMIC_LOCK_FREE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if defined(__CLANG_ATOMIC_BOOL_LOCK_FREE)
+# define ATOMIC_BOOL_LOCK_FREE __CLANG_ATOMIC_BOOL_LOCK_FREE
+# define ATOMIC_CHAR_LOCK_FREE __CLANG_ATOMIC_CHAR_LOCK_FREE
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+# define ATOMIC_CHAR8_T_LOCK_FREE __CLANG_ATOMIC_CHAR8_T_LOCK_FREE
+# endif
+# define ATOMIC_CHAR16_T_LOCK_FREE __CLANG_ATOMIC_CHAR16_T_LOCK_FREE
+# define ATOMIC_CHAR32_T_LOCK_FREE __CLANG_ATOMIC_CHAR32_T_LOCK_FREE
+# define ATOMIC_WCHAR_T_LOCK_FREE __CLANG_ATOMIC_WCHAR_T_LOCK_FREE
+# define ATOMIC_SHORT_LOCK_FREE __CLANG_ATOMIC_SHORT_LOCK_FREE
+# define ATOMIC_INT_LOCK_FREE __CLANG_ATOMIC_INT_LOCK_FREE
+# define ATOMIC_LONG_LOCK_FREE __CLANG_ATOMIC_LONG_LOCK_FREE
+# define ATOMIC_LLONG_LOCK_FREE __CLANG_ATOMIC_LLONG_LOCK_FREE
+# define ATOMIC_POINTER_LOCK_FREE __CLANG_ATOMIC_POINTER_LOCK_FREE
+#elif defined(__GCC_ATOMIC_BOOL_LOCK_FREE)
+# define ATOMIC_BOOL_LOCK_FREE __GCC_ATOMIC_BOOL_LOCK_FREE
+# define ATOMIC_CHAR_LOCK_FREE __GCC_ATOMIC_CHAR_LOCK_FREE
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+# define ATOMIC_CHAR8_T_LOCK_FREE __GCC_ATOMIC_CHAR8_T_LOCK_FREE
+# endif
+# define ATOMIC_CHAR16_T_LOCK_FREE __GCC_ATOMIC_CHAR16_T_LOCK_FREE
+# define ATOMIC_CHAR32_T_LOCK_FREE __GCC_ATOMIC_CHAR32_T_LOCK_FREE
+# define ATOMIC_WCHAR_T_LOCK_FREE __GCC_ATOMIC_WCHAR_T_LOCK_FREE
+# define ATOMIC_SHORT_LOCK_FREE __GCC_ATOMIC_SHORT_LOCK_FREE
+# define ATOMIC_INT_LOCK_FREE __GCC_ATOMIC_INT_LOCK_FREE
+# define ATOMIC_LONG_LOCK_FREE __GCC_ATOMIC_LONG_LOCK_FREE
+# define ATOMIC_LLONG_LOCK_FREE __GCC_ATOMIC_LLONG_LOCK_FREE
+# define ATOMIC_POINTER_LOCK_FREE __GCC_ATOMIC_POINTER_LOCK_FREE
+#endif
+
+#endif // _LIBCPP___ATOMIC_ATOMIC_LOCK_FREE_H
diff --git a/libcxx/include/__cxx03/__atomic/atomic_ref.h b/libcxx/include/__cxx03/__atomic/atomic_ref.h
new file mode 100644
index 00000000000000..b0180a37ab500c
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/atomic_ref.h
@@ -0,0 +1,378 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_ATOMIC_REF_H
+#define _LIBCPP___ATOMIC_ATOMIC_REF_H
+
+#include <__assert>
+#include <__atomic/atomic_sync.h>
+#include <__atomic/check_memory_order.h>
+#include <__atomic/to_gcc_order.h>
+#include <__concepts/arithmetic.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__type_traits/has_unique_object_representation.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// These types are required to make __atomic_is_always_lock_free work across GCC and Clang.
+// The purpose of this trick is to make sure that we provide an object with the correct alignment
+// to __atomic_is_always_lock_free, since that answer depends on the alignment.
+template <size_t _Alignment>
+struct __alignment_checker_type {
+ alignas(_Alignment) char __data;
+};
+
+template <size_t _Alignment>
+struct __get_aligner_instance {
+ static constexpr __alignment_checker_type<_Alignment> __instance{};
+};
+
+template <class _Tp>
+struct __atomic_ref_base {
+private:
+ _LIBCPP_HIDE_FROM_ABI static _Tp* __clear_padding(_Tp& __val) noexcept {
+ _Tp* __ptr = std::addressof(__val);
+# if __has_builtin(__builtin_clear_padding)
+ __builtin_clear_padding(__ptr);
+# endif
+ return __ptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static bool __compare_exchange(
+ _Tp* __ptr, _Tp* __expected, _Tp* __desired, bool __is_weak, int __success, int __failure) noexcept {
+ if constexpr (
+# if __has_builtin(__builtin_clear_padding)
+ has_unique_object_representations_v<_Tp> || floating_point<_Tp>
+# else
+ true // NOLINT(readability-simplify-boolean-expr)
+# endif
+ ) {
+ return __atomic_compare_exchange(__ptr, __expected, __desired, __is_weak, __success, __failure);
+ } else { // _Tp has padding bits and __builtin_clear_padding is available
+ __clear_padding(*__desired);
+ _Tp __copy = *__expected;
+ __clear_padding(__copy);
+ // The algorithm we use here is basically to perform `__atomic_compare_exchange` on the
+ // values until it has either succeeded, or failed because the value representation of the
+ // objects involved was different. This is why we loop around __atomic_compare_exchange:
+ // we basically loop until its failure is caused by the value representation of the objects
+ // being different, not only their object representation.
+ while (true) {
+ _Tp __prev = __copy;
+ if (__atomic_compare_exchange(__ptr, std::addressof(__copy), __desired, __is_weak, __success, __failure)) {
+ return true;
+ }
+ _Tp __curr = __copy;
+ if (std::memcmp(__clear_padding(__prev), __clear_padding(__curr), sizeof(_Tp)) != 0) {
+ // Value representation without padding bits do not compare equal ->
+ // write the current content of *ptr into *expected
+ std::memcpy(__expected, std::addressof(__copy), sizeof(_Tp));
+ return false;
+ }
+ }
+ }
+ }
+
+ friend struct __atomic_waitable_traits<__atomic_ref_base<_Tp>>;
+
+ // require types that are 1, 2, 4, 8, or 16 bytes in length to be aligned to at least their size to be potentially
+ // used lock-free
+ static constexpr size_t __min_alignment = (sizeof(_Tp) & (sizeof(_Tp) - 1)) || (sizeof(_Tp) > 16) ? 0 : sizeof(_Tp);
+
+public:
+ using value_type = _Tp;
+
+ static constexpr size_t required_alignment = alignof(_Tp) > __min_alignment ? alignof(_Tp) : __min_alignment;
+
+ // The __atomic_always_lock_free builtin takes into account the alignment of the pointer if provided,
+ // so we create a fake pointer with a suitable alignment when querying it. Note that we are guaranteed
+ // that the pointer is going to be aligned properly at runtime because that is a (checked) precondition
+ // of atomic_ref's constructor.
+ static constexpr bool is_always_lock_free =
+ __atomic_always_lock_free(sizeof(_Tp), &__get_aligner_instance<required_alignment>::__instance);
+
+ _LIBCPP_HIDE_FROM_ABI bool is_lock_free() const noexcept { return __atomic_is_lock_free(sizeof(_Tp), __ptr_); }
+
+ _LIBCPP_HIDE_FROM_ABI void store(_Tp __desired, memory_order __order = memory_order::seq_cst) const noexcept
+ _LIBCPP_CHECK_STORE_MEMORY_ORDER(__order) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __order == memory_order::relaxed || __order == memory_order::release || __order == memory_order::seq_cst,
+ "atomic_ref: memory order argument to atomic store operation is invalid");
+ __atomic_store(__ptr_, __clear_padding(__desired), std::__to_gcc_order(__order));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator=(_Tp __desired) const noexcept {
+ store(__desired);
+ return __desired;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp load(memory_order __order = memory_order::seq_cst) const noexcept
+ _LIBCPP_CHECK_LOAD_MEMORY_ORDER(__order) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __order == memory_order::relaxed || __order == memory_order::consume || __order == memory_order::acquire ||
+ __order == memory_order::seq_cst,
+ "atomic_ref: memory order argument to atomic load operation is invalid");
+ alignas(_Tp) byte __mem[sizeof(_Tp)];
+ auto* __ret = reinterpret_cast<_Tp*>(__mem);
+ __atomic_load(__ptr_, __ret, std::__to_gcc_order(__order));
+ return *__ret;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI operator _Tp() const noexcept { return load(); }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp exchange(_Tp __desired, memory_order __order = memory_order::seq_cst) const noexcept {
+ alignas(_Tp) byte __mem[sizeof(_Tp)];
+ auto* __ret = reinterpret_cast<_Tp*>(__mem);
+ __atomic_exchange(__ptr_, __clear_padding(__desired), __ret, std::__to_gcc_order(__order));
+ return *__ret;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_weak(_Tp& __expected, _Tp __desired, memory_order __success, memory_order __failure) const noexcept
+ _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__success, __failure) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __failure == memory_order::relaxed || __failure == memory_order::consume ||
+ __failure == memory_order::acquire || __failure == memory_order::seq_cst,
+ "atomic_ref: failure memory order argument to weak atomic compare-and-exchange operation is invalid");
+ return __compare_exchange(
+ __ptr_,
+ std::addressof(__expected),
+ std::addressof(__desired),
+ true,
+ std::__to_gcc_order(__success),
+ std::__to_gcc_order(__failure));
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_strong(_Tp& __expected, _Tp __desired, memory_order __success, memory_order __failure) const noexcept
+ _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__success, __failure) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __failure == memory_order::relaxed || __failure == memory_order::consume ||
+ __failure == memory_order::acquire || __failure == memory_order::seq_cst,
+ "atomic_ref: failure memory order argument to strong atomic compare-and-exchange operation is invalid");
+ return __compare_exchange(
+ __ptr_,
+ std::addressof(__expected),
+ std::addressof(__desired),
+ false,
+ std::__to_gcc_order(__success),
+ std::__to_gcc_order(__failure));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_weak(_Tp& __expected, _Tp __desired, memory_order __order = memory_order::seq_cst) const noexcept {
+ return __compare_exchange(
+ __ptr_,
+ std::addressof(__expected),
+ std::addressof(__desired),
+ true,
+ std::__to_gcc_order(__order),
+ std::__to_gcc_failure_order(__order));
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ compare_exchange_strong(_Tp& __expected, _Tp __desired, memory_order __order = memory_order::seq_cst) const noexcept {
+ return __compare_exchange(
+ __ptr_,
+ std::addressof(__expected),
+ std::addressof(__desired),
+ false,
+ std::__to_gcc_order(__order),
+ std::__to_gcc_failure_order(__order));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void wait(_Tp __old, memory_order __order = memory_order::seq_cst) const noexcept
+ _LIBCPP_CHECK_WAIT_MEMORY_ORDER(__order) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __order == memory_order::relaxed || __order == memory_order::consume || __order == memory_order::acquire ||
+ __order == memory_order::seq_cst,
+ "atomic_ref: memory order argument to atomic wait operation is invalid");
+ std::__atomic_wait(*this, __old, __order);
+ }
+ _LIBCPP_HIDE_FROM_ABI void notify_one() const noexcept { std::__atomic_notify_one(*this); }
+ _LIBCPP_HIDE_FROM_ABI void notify_all() const noexcept { std::__atomic_notify_all(*this); }
+
+protected:
+ typedef _Tp _Aligned_Tp __attribute__((aligned(required_alignment)));
+ _Aligned_Tp* __ptr_;
+
+ _LIBCPP_HIDE_FROM_ABI __atomic_ref_base(_Tp& __obj) : __ptr_(std::addressof(__obj)) {}
+};
+
+template <class _Tp>
+struct __atomic_waitable_traits<__atomic_ref_base<_Tp>> {
+ static _LIBCPP_HIDE_FROM_ABI _Tp __atomic_load(const __atomic_ref_base<_Tp>& __a, memory_order __order) {
+ return __a.load(__order);
+ }
+ static _LIBCPP_HIDE_FROM_ABI const _Tp* __atomic_contention_address(const __atomic_ref_base<_Tp>& __a) {
+ return __a.__ptr_;
+ }
+};
+
+template <class _Tp>
+struct atomic_ref : public __atomic_ref_base<_Tp> {
+ static_assert(is_trivially_copyable_v<_Tp>, "std::atomic_ref<T> requires that 'T' be a trivially copyable type");
+
+ using __base = __atomic_ref_base<_Tp>;
+
+ _LIBCPP_HIDE_FROM_ABI explicit atomic_ref(_Tp& __obj) : __base(__obj) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ reinterpret_cast<uintptr_t>(std::addressof(__obj)) % __base::required_alignment == 0,
+ "atomic_ref ctor: referenced object must be aligned to required_alignment");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI atomic_ref(const atomic_ref&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator=(_Tp __desired) const noexcept { return __base::operator=(__desired); }
+
+ atomic_ref& operator=(const atomic_ref&) = delete;
+};
+
+template <class _Tp>
+ requires(std::integral<_Tp> && !std::same_as<bool, _Tp>)
+struct atomic_ref<_Tp> : public __atomic_ref_base<_Tp> {
+ using __base = __atomic_ref_base<_Tp>;
+
+ using difference_type = __base::value_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit atomic_ref(_Tp& __obj) : __base(__obj) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ reinterpret_cast<uintptr_t>(std::addressof(__obj)) % __base::required_alignment == 0,
+ "atomic_ref ctor: referenced object must be aligned to required_alignment");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI atomic_ref(const atomic_ref&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator=(_Tp __desired) const noexcept { return __base::operator=(__desired); }
+
+ atomic_ref& operator=(const atomic_ref&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_add(_Tp __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ return __atomic_fetch_add(this->__ptr_, __arg, std::__to_gcc_order(__order));
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_sub(_Tp __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ return __atomic_fetch_sub(this->__ptr_, __arg, std::__to_gcc_order(__order));
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_and(_Tp __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ return __atomic_fetch_and(this->__ptr_, __arg, std::__to_gcc_order(__order));
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_or(_Tp __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ return __atomic_fetch_or(this->__ptr_, __arg, std::__to_gcc_order(__order));
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_xor(_Tp __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ return __atomic_fetch_xor(this->__ptr_, __arg, std::__to_gcc_order(__order));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator++(int) const noexcept { return fetch_add(_Tp(1)); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator--(int) const noexcept { return fetch_sub(_Tp(1)); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator++() const noexcept { return fetch_add(_Tp(1)) + _Tp(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator--() const noexcept { return fetch_sub(_Tp(1)) - _Tp(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator+=(_Tp __arg) const noexcept { return fetch_add(__arg) + __arg; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator-=(_Tp __arg) const noexcept { return fetch_sub(__arg) - __arg; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator&=(_Tp __arg) const noexcept { return fetch_and(__arg) & __arg; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator|=(_Tp __arg) const noexcept { return fetch_or(__arg) | __arg; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator^=(_Tp __arg) const noexcept { return fetch_xor(__arg) ^ __arg; }
+};
+
+template <class _Tp>
+ requires std::floating_point<_Tp>
+struct atomic_ref<_Tp> : public __atomic_ref_base<_Tp> {
+ using __base = __atomic_ref_base<_Tp>;
+
+ using difference_type = __base::value_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit atomic_ref(_Tp& __obj) : __base(__obj) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ reinterpret_cast<uintptr_t>(std::addressof(__obj)) % __base::required_alignment == 0,
+ "atomic_ref ctor: referenced object must be aligned to required_alignment");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI atomic_ref(const atomic_ref&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator=(_Tp __desired) const noexcept { return __base::operator=(__desired); }
+
+ atomic_ref& operator=(const atomic_ref&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_add(_Tp __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ _Tp __old = this->load(memory_order_relaxed);
+ _Tp __new = __old + __arg;
+ while (!this->compare_exchange_weak(__old, __new, __order, memory_order_relaxed)) {
+ __new = __old + __arg;
+ }
+ return __old;
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp fetch_sub(_Tp __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ _Tp __old = this->load(memory_order_relaxed);
+ _Tp __new = __old - __arg;
+ while (!this->compare_exchange_weak(__old, __new, __order, memory_order_relaxed)) {
+ __new = __old - __arg;
+ }
+ return __old;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator+=(_Tp __arg) const noexcept { return fetch_add(__arg) + __arg; }
+ _LIBCPP_HIDE_FROM_ABI _Tp operator-=(_Tp __arg) const noexcept { return fetch_sub(__arg) - __arg; }
+};
+
+template <class _Tp>
+struct atomic_ref<_Tp*> : public __atomic_ref_base<_Tp*> {
+ using __base = __atomic_ref_base<_Tp*>;
+
+ using difference_type = ptrdiff_t;
+
+ _LIBCPP_HIDE_FROM_ABI explicit atomic_ref(_Tp*& __ptr) : __base(__ptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator=(_Tp* __desired) const noexcept { return __base::operator=(__desired); }
+
+ atomic_ref& operator=(const atomic_ref&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* fetch_add(ptrdiff_t __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ return __atomic_fetch_add(this->__ptr_, __arg * sizeof(_Tp), std::__to_gcc_order(__order));
+ }
+ _LIBCPP_HIDE_FROM_ABI _Tp* fetch_sub(ptrdiff_t __arg, memory_order __order = memory_order_seq_cst) const noexcept {
+ return __atomic_fetch_sub(this->__ptr_, __arg * sizeof(_Tp), std::__to_gcc_order(__order));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator++(int) const noexcept { return fetch_add(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator--(int) const noexcept { return fetch_sub(1); }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator++() const noexcept { return fetch_add(1) + 1; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator--() const noexcept { return fetch_sub(1) - 1; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator+=(ptrdiff_t __arg) const noexcept { return fetch_add(__arg) + __arg; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator-=(ptrdiff_t __arg) const noexcept { return fetch_sub(__arg) - __arg; }
+};
+
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(atomic_ref);
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP__ATOMIC_ATOMIC_REF_H
diff --git a/libcxx/include/__cxx03/__atomic/atomic_sync.h b/libcxx/include/__cxx03/__atomic/atomic_sync.h
new file mode 100644
index 00000000000000..aaf81f58731a98
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/atomic_sync.h
@@ -0,0 +1,205 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_ATOMIC_SYNC_H
+#define _LIBCPP___ATOMIC_ATOMIC_SYNC_H
+
+#include <__atomic/contention_t.h>
+#include <__atomic/cxx_atomic_impl.h>
+#include <__atomic/memory_order.h>
+#include <__atomic/to_gcc_order.h>
+#include <__chrono/duration.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__thread/poll_with_backoff.h>
+#include <__thread/support.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <cstring>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// The customisation points to enable the following functions:
+// - __atomic_wait
+// - __atomic_wait_unless
+// - __atomic_notify_one
+// - __atomic_notify_all
+// Note that std::atomic<T>::wait was back-ported to C++03
+// The below implementations look ugly to support C++03
+template <class _Tp, class = void>
+struct __atomic_waitable_traits {
+ template <class _AtomicWaitable>
+ static void __atomic_load(_AtomicWaitable&&, memory_order) = delete;
+
+ template <class _AtomicWaitable>
+ static void __atomic_contention_address(_AtomicWaitable&&) = delete;
+};
+
+template <class _Tp, class = void>
+struct __atomic_waitable : false_type {};
+
+template <class _Tp>
+struct __atomic_waitable< _Tp,
+ __void_t<decltype(__atomic_waitable_traits<__decay_t<_Tp> >::__atomic_load(
+ std::declval<const _Tp&>(), std::declval<memory_order>())),
+ decltype(__atomic_waitable_traits<__decay_t<_Tp> >::__atomic_contention_address(
+ std::declval<const _Tp&>()))> > : true_type {};
+
+template <class _AtomicWaitable, class _Poll>
+struct __atomic_wait_poll_impl {
+ const _AtomicWaitable& __a_;
+ _Poll __poll_;
+ memory_order __order_;
+
+ _LIBCPP_HIDE_FROM_ABI bool operator()() const {
+ auto __current_val = __atomic_waitable_traits<__decay_t<_AtomicWaitable> >::__atomic_load(__a_, __order_);
+ return __poll_(__current_val);
+ }
+};
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI void __cxx_atomic_notify_one(void const volatile*) _NOEXCEPT;
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI void __cxx_atomic_notify_all(void const volatile*) _NOEXCEPT;
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI __cxx_contention_t
+__libcpp_atomic_monitor(void const volatile*) _NOEXCEPT;
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI void
+__libcpp_atomic_wait(void const volatile*, __cxx_contention_t) _NOEXCEPT;
+
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI void
+__cxx_atomic_notify_one(__cxx_atomic_contention_t const volatile*) _NOEXCEPT;
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI void
+__cxx_atomic_notify_all(__cxx_atomic_contention_t const volatile*) _NOEXCEPT;
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI __cxx_contention_t
+__libcpp_atomic_monitor(__cxx_atomic_contention_t const volatile*) _NOEXCEPT;
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI void
+__libcpp_atomic_wait(__cxx_atomic_contention_t const volatile*, __cxx_contention_t) _NOEXCEPT;
+
+template <class _AtomicWaitable, class _Poll>
+struct __atomic_wait_backoff_impl {
+ const _AtomicWaitable& __a_;
+ _Poll __poll_;
+ memory_order __order_;
+
+ using __waitable_traits = __atomic_waitable_traits<__decay_t<_AtomicWaitable> >;
+
+ _LIBCPP_AVAILABILITY_SYNC
+ _LIBCPP_HIDE_FROM_ABI bool
+ __update_monitor_val_and_poll(__cxx_atomic_contention_t const volatile*, __cxx_contention_t& __monitor_val) const {
+ // In case the contention type happens to be __cxx_atomic_contention_t, i.e. __cxx_atomic_impl<int64_t>,
+ // the platform wait is directly monitoring the atomic value itself.
+ // `__poll_` takes the current value of the atomic as an in-out argument
+ // to potentially modify it. After it returns, `__monitor` has a value
+ // which can be safely waited on by `std::__libcpp_atomic_wait` without any
+ // ABA style issues.
+ __monitor_val = __waitable_traits::__atomic_load(__a_, __order_);
+ return __poll_(__monitor_val);
+ }
+
+ _LIBCPP_AVAILABILITY_SYNC
+ _LIBCPP_HIDE_FROM_ABI bool
+ __update_monitor_val_and_poll(void const volatile* __contention_address, __cxx_contention_t& __monitor_val) const {
+ // In case the contention type is anything else, platform wait is monitoring a __cxx_atomic_contention_t
+ // from the global pool, the monitor comes from __libcpp_atomic_monitor
+ __monitor_val = std::__libcpp_atomic_monitor(__contention_address);
+ auto __current_val = __waitable_traits::__atomic_load(__a_, __order_);
+ return __poll_(__current_val);
+ }
+
+ _LIBCPP_AVAILABILITY_SYNC
+ _LIBCPP_HIDE_FROM_ABI bool operator()(chrono::nanoseconds __elapsed) const {
+ if (__elapsed > chrono::microseconds(64)) {
+ auto __contention_address = __waitable_traits::__atomic_contention_address(__a_);
+ __cxx_contention_t __monitor_val;
+ if (__update_monitor_val_and_poll(__contention_address, __monitor_val))
+ return true;
+ std::__libcpp_atomic_wait(__contention_address, __monitor_val);
+ } else if (__elapsed > chrono::microseconds(4))
+ __libcpp_thread_yield();
+ else {
+ } // poll
+ return false;
+ }
+};
+
+// The semantics of this function are similar to `atomic`'s
+// `.wait(T old, std::memory_order order)`, but instead of having a hardcoded
+// predicate (is the loaded value unequal to `old`?), the predicate function is
+// specified as an argument. The loaded value is given as an in-out argument to
+// the predicate. If the predicate function returns `true`,
+// `__atomic_wait_unless` will return. If the predicate function returns
+// `false`, it must set the argument to its current understanding of the atomic
+// value. The predicate function must not return `false` spuriously.
+template <class _AtomicWaitable, class _Poll>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+__atomic_wait_unless(const _AtomicWaitable& __a, _Poll&& __poll, memory_order __order) {
+ static_assert(__atomic_waitable<_AtomicWaitable>::value, "");
+ __atomic_wait_poll_impl<_AtomicWaitable, __decay_t<_Poll> > __poll_impl = {__a, __poll, __order};
+ __atomic_wait_backoff_impl<_AtomicWaitable, __decay_t<_Poll> > __backoff_fn = {__a, __poll, __order};
+ std::__libcpp_thread_poll_with_backoff(__poll_impl, __backoff_fn);
+}
+
+template <class _AtomicWaitable>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void __atomic_notify_one(const _AtomicWaitable& __a) {
+ static_assert(__atomic_waitable<_AtomicWaitable>::value, "");
+ std::__cxx_atomic_notify_one(__atomic_waitable_traits<__decay_t<_AtomicWaitable> >::__atomic_contention_address(__a));
+}
+
+template <class _AtomicWaitable>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void __atomic_notify_all(const _AtomicWaitable& __a) {
+ static_assert(__atomic_waitable<_AtomicWaitable>::value, "");
+ std::__cxx_atomic_notify_all(__atomic_waitable_traits<__decay_t<_AtomicWaitable> >::__atomic_contention_address(__a));
+}
+
+#else // _LIBCPP_HAS_NO_THREADS
+
+template <class _AtomicWaitable, class _Poll>
+_LIBCPP_HIDE_FROM_ABI void __atomic_wait_unless(const _AtomicWaitable& __a, _Poll&& __poll, memory_order __order) {
+ __atomic_wait_poll_impl<_AtomicWaitable, __decay_t<_Poll> > __poll_fn = {__a, __poll, __order};
+ std::__libcpp_thread_poll_with_backoff(__poll_fn, __spinning_backoff_policy());
+}
+
+template <class _AtomicWaitable>
+_LIBCPP_HIDE_FROM_ABI void __atomic_notify_one(const _AtomicWaitable&) {}
+
+template <class _AtomicWaitable>
+_LIBCPP_HIDE_FROM_ABI void __atomic_notify_all(const _AtomicWaitable&) {}
+
+#endif // _LIBCPP_HAS_NO_THREADS
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_nonatomic_compare_equal(_Tp const& __lhs, _Tp const& __rhs) {
+ return std::memcmp(std::addressof(__lhs), std::addressof(__rhs), sizeof(_Tp)) == 0;
+}
+
+template <class _Tp>
+struct __atomic_compare_unequal_to {
+ _Tp __val_;
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __arg) const {
+ return !std::__cxx_nonatomic_compare_equal(__arg, __val_);
+ }
+};
+
+template <class _AtomicWaitable, class _Up>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void
+__atomic_wait(_AtomicWaitable& __a, _Up __val, memory_order __order) {
+ static_assert(__atomic_waitable<_AtomicWaitable>::value, "");
+ __atomic_compare_unequal_to<_Up> __nonatomic_equal = {__val};
+ std::__atomic_wait_unless(__a, __nonatomic_equal, __order);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_ATOMIC_SYNC_H
diff --git a/libcxx/include/__cxx03/__atomic/check_memory_order.h b/libcxx/include/__cxx03/__atomic/check_memory_order.h
new file mode 100644
index 00000000000000..536f764a619026
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/check_memory_order.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_CHECK_MEMORY_ORDER_H
+#define _LIBCPP___ATOMIC_CHECK_MEMORY_ORDER_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#define _LIBCPP_CHECK_STORE_MEMORY_ORDER(__m) \
+ _LIBCPP_DIAGNOSE_WARNING(__m == memory_order_consume || __m == memory_order_acquire || __m == memory_order_acq_rel, \
+ "memory order argument to atomic operation is invalid")
+
+#define _LIBCPP_CHECK_LOAD_MEMORY_ORDER(__m) \
+ _LIBCPP_DIAGNOSE_WARNING(__m == memory_order_release || __m == memory_order_acq_rel, \
+ "memory order argument to atomic operation is invalid")
+
+#define _LIBCPP_CHECK_EXCHANGE_MEMORY_ORDER(__m, __f) \
+ _LIBCPP_DIAGNOSE_WARNING(__f == memory_order_release || __f == memory_order_acq_rel, \
+ "memory order argument to atomic operation is invalid")
+
+#define _LIBCPP_CHECK_WAIT_MEMORY_ORDER(__m) \
+ _LIBCPP_DIAGNOSE_WARNING(__m == memory_order_release || __m == memory_order_acq_rel, \
+ "memory order argument to atomic operation is invalid")
+
+#endif // _LIBCPP___ATOMIC_CHECK_MEMORY_ORDER_H
diff --git a/libcxx/include/__cxx03/__atomic/contention_t.h b/libcxx/include/__cxx03/__atomic/contention_t.h
new file mode 100644
index 00000000000000..65890f338ce990
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/contention_t.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_CONTENTION_T_H
+#define _LIBCPP___ATOMIC_CONTENTION_T_H
+
+#include <__atomic/cxx_atomic_impl.h>
+#include <__config>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if defined(__linux__) || (defined(_AIX) && !defined(__64BIT__))
+using __cxx_contention_t = int32_t;
+#else
+using __cxx_contention_t = int64_t;
+#endif // __linux__ || (_AIX && !__64BIT__)
+
+using __cxx_atomic_contention_t = __cxx_atomic_impl<__cxx_contention_t>;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_CONTENTION_T_H
diff --git a/libcxx/include/__cxx03/__atomic/cxx_atomic_impl.h b/libcxx/include/__cxx03/__atomic/cxx_atomic_impl.h
new file mode 100644
index 00000000000000..18e88aa97bec75
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/cxx_atomic_impl.h
@@ -0,0 +1,510 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_CXX_ATOMIC_IMPL_H
+#define _LIBCPP___ATOMIC_CXX_ATOMIC_IMPL_H
+
+#include <__atomic/memory_order.h>
+#include <__atomic/to_gcc_order.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <__type_traits/remove_const.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if defined(_LIBCPP_HAS_GCC_ATOMIC_IMP)
+
+// [atomics.types.generic]p1 guarantees _Tp is trivially copyable. Because
+// the default operator= in an object is not volatile, a byte-by-byte copy
+// is required.
+template <typename _Tp, typename _Tv, __enable_if_t<is_assignable<_Tp&, _Tv>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void __cxx_atomic_assign_volatile(_Tp& __a_value, _Tv const& __val) {
+ __a_value = __val;
+}
+template <typename _Tp, typename _Tv, __enable_if_t<is_assignable<_Tp&, _Tv>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI void __cxx_atomic_assign_volatile(_Tp volatile& __a_value, _Tv volatile const& __val) {
+ volatile char* __to = reinterpret_cast<volatile char*>(std::addressof(__a_value));
+ volatile char* __end = __to + sizeof(_Tp);
+ volatile const char* __from = reinterpret_cast<volatile const char*>(std::addressof(__val));
+ while (__to != __end)
+ *__to++ = *__from++;
+}
+
+template <typename _Tp>
+struct __cxx_atomic_base_impl {
+ _LIBCPP_HIDE_FROM_ABI
+# ifndef _LIBCPP_CXX03_LANG
+ __cxx_atomic_base_impl() _NOEXCEPT = default;
+# else
+ __cxx_atomic_base_impl() _NOEXCEPT : __a_value() {
+ }
+# endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_CONSTEXPR explicit __cxx_atomic_base_impl(_Tp value) _NOEXCEPT : __a_value(value) {}
+ _Tp __a_value;
+};
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI void __cxx_atomic_init(volatile __cxx_atomic_base_impl<_Tp>* __a, _Tp __val) {
+ __cxx_atomic_assign_volatile(__a->__a_value, __val);
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI void __cxx_atomic_init(__cxx_atomic_base_impl<_Tp>* __a, _Tp __val) {
+ __a->__a_value = __val;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline void __cxx_atomic_thread_fence(memory_order __order) {
+ __atomic_thread_fence(__to_gcc_order(__order));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline void __cxx_atomic_signal_fence(memory_order __order) {
+ __atomic_signal_fence(__to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+__cxx_atomic_store(volatile __cxx_atomic_base_impl<_Tp>* __a, _Tp __val, memory_order __order) {
+ __atomic_store(std::addressof(__a->__a_value), std::addressof(__val), __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI void __cxx_atomic_store(__cxx_atomic_base_impl<_Tp>* __a, _Tp __val, memory_order __order) {
+ __atomic_store(std::addressof(__a->__a_value), std::addressof(__val), __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp __cxx_atomic_load(const volatile __cxx_atomic_base_impl<_Tp>* __a, memory_order __order) {
+ _Tp __ret;
+ __atomic_load(std::addressof(__a->__a_value), std::addressof(__ret), __to_gcc_order(__order));
+ return __ret;
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+__cxx_atomic_load_inplace(const volatile __cxx_atomic_base_impl<_Tp>* __a, _Tp* __dst, memory_order __order) {
+ __atomic_load(std::addressof(__a->__a_value), __dst, __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+__cxx_atomic_load_inplace(const __cxx_atomic_base_impl<_Tp>* __a, _Tp* __dst, memory_order __order) {
+ __atomic_load(std::addressof(__a->__a_value), __dst, __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp __cxx_atomic_load(const __cxx_atomic_base_impl<_Tp>* __a, memory_order __order) {
+ _Tp __ret;
+ __atomic_load(std::addressof(__a->__a_value), std::addressof(__ret), __to_gcc_order(__order));
+ return __ret;
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_exchange(volatile __cxx_atomic_base_impl<_Tp>* __a, _Tp __value, memory_order __order) {
+ _Tp __ret;
+ __atomic_exchange(
+ std::addressof(__a->__a_value), std::addressof(__value), std::addressof(__ret), __to_gcc_order(__order));
+ return __ret;
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp __cxx_atomic_exchange(__cxx_atomic_base_impl<_Tp>* __a, _Tp __value, memory_order __order) {
+ _Tp __ret;
+ __atomic_exchange(
+ std::addressof(__a->__a_value), std::addressof(__value), std::addressof(__ret), __to_gcc_order(__order));
+ return __ret;
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_atomic_compare_exchange_strong(
+ volatile __cxx_atomic_base_impl<_Tp>* __a,
+ _Tp* __expected,
+ _Tp __value,
+ memory_order __success,
+ memory_order __failure) {
+ return __atomic_compare_exchange(
+ std::addressof(__a->__a_value),
+ __expected,
+ std::addressof(__value),
+ false,
+ __to_gcc_order(__success),
+ __to_gcc_failure_order(__failure));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_atomic_compare_exchange_strong(
+ __cxx_atomic_base_impl<_Tp>* __a, _Tp* __expected, _Tp __value, memory_order __success, memory_order __failure) {
+ return __atomic_compare_exchange(
+ std::addressof(__a->__a_value),
+ __expected,
+ std::addressof(__value),
+ false,
+ __to_gcc_order(__success),
+ __to_gcc_failure_order(__failure));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_atomic_compare_exchange_weak(
+ volatile __cxx_atomic_base_impl<_Tp>* __a,
+ _Tp* __expected,
+ _Tp __value,
+ memory_order __success,
+ memory_order __failure) {
+ return __atomic_compare_exchange(
+ std::addressof(__a->__a_value),
+ __expected,
+ std::addressof(__value),
+ true,
+ __to_gcc_order(__success),
+ __to_gcc_failure_order(__failure));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_atomic_compare_exchange_weak(
+ __cxx_atomic_base_impl<_Tp>* __a, _Tp* __expected, _Tp __value, memory_order __success, memory_order __failure) {
+ return __atomic_compare_exchange(
+ std::addressof(__a->__a_value),
+ __expected,
+ std::addressof(__value),
+ true,
+ __to_gcc_order(__success),
+ __to_gcc_failure_order(__failure));
+}
+
+template <typename _Tp>
+struct __skip_amt {
+ enum { value = 1 };
+};
+
+template <typename _Tp>
+struct __skip_amt<_Tp*> {
+ enum { value = sizeof(_Tp) };
+};
+
+// FIXME: Haven't figured out what the spec says about using arrays with
+// atomic_fetch_add. Force a failure rather than creating bad behavior.
+template <typename _Tp>
+struct __skip_amt<_Tp[]> {};
+template <typename _Tp, int n>
+struct __skip_amt<_Tp[n]> {};
+
+template <typename _Tp, typename _Td>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_add(volatile __cxx_atomic_base_impl<_Tp>* __a, _Td __delta, memory_order __order) {
+ return __atomic_fetch_add(std::addressof(__a->__a_value), __delta * __skip_amt<_Tp>::value, __to_gcc_order(__order));
+}
+
+template <typename _Tp, typename _Td>
+_LIBCPP_HIDE_FROM_ABI _Tp __cxx_atomic_fetch_add(__cxx_atomic_base_impl<_Tp>* __a, _Td __delta, memory_order __order) {
+ return __atomic_fetch_add(std::addressof(__a->__a_value), __delta * __skip_amt<_Tp>::value, __to_gcc_order(__order));
+}
+
+template <typename _Tp, typename _Td>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_sub(volatile __cxx_atomic_base_impl<_Tp>* __a, _Td __delta, memory_order __order) {
+ return __atomic_fetch_sub(std::addressof(__a->__a_value), __delta * __skip_amt<_Tp>::value, __to_gcc_order(__order));
+}
+
+template <typename _Tp, typename _Td>
+_LIBCPP_HIDE_FROM_ABI _Tp __cxx_atomic_fetch_sub(__cxx_atomic_base_impl<_Tp>* __a, _Td __delta, memory_order __order) {
+ return __atomic_fetch_sub(std::addressof(__a->__a_value), __delta * __skip_amt<_Tp>::value, __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_and(volatile __cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) {
+ return __atomic_fetch_and(std::addressof(__a->__a_value), __pattern, __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_and(__cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) {
+ return __atomic_fetch_and(std::addressof(__a->__a_value), __pattern, __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_or(volatile __cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) {
+ return __atomic_fetch_or(std::addressof(__a->__a_value), __pattern, __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp __cxx_atomic_fetch_or(__cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) {
+ return __atomic_fetch_or(std::addressof(__a->__a_value), __pattern, __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_xor(volatile __cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) {
+ return __atomic_fetch_xor(std::addressof(__a->__a_value), __pattern, __to_gcc_order(__order));
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_xor(__cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) {
+ return __atomic_fetch_xor(std::addressof(__a->__a_value), __pattern, __to_gcc_order(__order));
+}
+
+# define __cxx_atomic_is_lock_free(__s) __atomic_is_lock_free(__s, 0)
+
+#elif defined(_LIBCPP_HAS_C_ATOMIC_IMP)
+
+template <typename _Tp>
+struct __cxx_atomic_base_impl {
+ _LIBCPP_HIDE_FROM_ABI
+# ifndef _LIBCPP_CXX03_LANG
+ __cxx_atomic_base_impl() _NOEXCEPT = default;
+# else
+ __cxx_atomic_base_impl() _NOEXCEPT : __a_value() {
+ }
+# endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_CONSTEXPR explicit __cxx_atomic_base_impl(_Tp __value) _NOEXCEPT : __a_value(__value) {}
+ _LIBCPP_DISABLE_EXTENSION_WARNING _Atomic(_Tp) __a_value;
+};
+
+# define __cxx_atomic_is_lock_free(__s) __c11_atomic_is_lock_free(__s)
+
+_LIBCPP_HIDE_FROM_ABI inline void __cxx_atomic_thread_fence(memory_order __order) _NOEXCEPT {
+ __c11_atomic_thread_fence(static_cast<__memory_order_underlying_t>(__order));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline void __cxx_atomic_signal_fence(memory_order __order) _NOEXCEPT {
+ __c11_atomic_signal_fence(static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void __cxx_atomic_init(__cxx_atomic_base_impl<_Tp> volatile* __a, _Tp __val) _NOEXCEPT {
+ __c11_atomic_init(std::addressof(__a->__a_value), __val);
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void __cxx_atomic_init(__cxx_atomic_base_impl<_Tp>* __a, _Tp __val) _NOEXCEPT {
+ __c11_atomic_init(std::addressof(__a->__a_value), __val);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+__cxx_atomic_store(__cxx_atomic_base_impl<_Tp> volatile* __a, _Tp __val, memory_order __order) _NOEXCEPT {
+ __c11_atomic_store(std::addressof(__a->__a_value), __val, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+__cxx_atomic_store(__cxx_atomic_base_impl<_Tp>* __a, _Tp __val, memory_order __order) _NOEXCEPT {
+ __c11_atomic_store(std::addressof(__a->__a_value), __val, static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_load(__cxx_atomic_base_impl<_Tp> const volatile* __a, memory_order __order) _NOEXCEPT {
+ using __ptr_type = __remove_const_t<decltype(__a->__a_value)>*;
+ return __c11_atomic_load(
+ const_cast<__ptr_type>(std::addressof(__a->__a_value)), static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp __cxx_atomic_load(__cxx_atomic_base_impl<_Tp> const* __a, memory_order __order) _NOEXCEPT {
+ using __ptr_type = __remove_const_t<decltype(__a->__a_value)>*;
+ return __c11_atomic_load(
+ const_cast<__ptr_type>(std::addressof(__a->__a_value)), static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+__cxx_atomic_load_inplace(__cxx_atomic_base_impl<_Tp> const volatile* __a, _Tp* __dst, memory_order __order) _NOEXCEPT {
+ using __ptr_type = __remove_const_t<decltype(__a->__a_value)>*;
+ *__dst = __c11_atomic_load(
+ const_cast<__ptr_type>(std::addressof(__a->__a_value)), static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+__cxx_atomic_load_inplace(__cxx_atomic_base_impl<_Tp> const* __a, _Tp* __dst, memory_order __order) _NOEXCEPT {
+ using __ptr_type = __remove_const_t<decltype(__a->__a_value)>*;
+ *__dst = __c11_atomic_load(
+ const_cast<__ptr_type>(std::addressof(__a->__a_value)), static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_exchange(__cxx_atomic_base_impl<_Tp> volatile* __a, _Tp __value, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_exchange(
+ std::addressof(__a->__a_value), __value, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_exchange(__cxx_atomic_base_impl<_Tp>* __a, _Tp __value, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_exchange(
+ std::addressof(__a->__a_value), __value, static_cast<__memory_order_underlying_t>(__order));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline _LIBCPP_CONSTEXPR memory_order __to_failure_order(memory_order __order) {
+ // Avoid switch statement to make this a constexpr.
+ return __order == memory_order_release
+ ? memory_order_relaxed
+ : (__order == memory_order_acq_rel ? memory_order_acquire : __order);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_atomic_compare_exchange_strong(
+ __cxx_atomic_base_impl<_Tp> volatile* __a,
+ _Tp* __expected,
+ _Tp __value,
+ memory_order __success,
+ memory_order __failure) _NOEXCEPT {
+ return __c11_atomic_compare_exchange_strong(
+ std::addressof(__a->__a_value),
+ __expected,
+ __value,
+ static_cast<__memory_order_underlying_t>(__success),
+ static_cast<__memory_order_underlying_t>(__to_failure_order(__failure)));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_atomic_compare_exchange_strong(
+ __cxx_atomic_base_impl<_Tp>* __a, _Tp* __expected, _Tp __value, memory_order __success, memory_order __failure)
+ _NOEXCEPT {
+ return __c11_atomic_compare_exchange_strong(
+ std::addressof(__a->__a_value),
+ __expected,
+ __value,
+ static_cast<__memory_order_underlying_t>(__success),
+ static_cast<__memory_order_underlying_t>(__to_failure_order(__failure)));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_atomic_compare_exchange_weak(
+ __cxx_atomic_base_impl<_Tp> volatile* __a,
+ _Tp* __expected,
+ _Tp __value,
+ memory_order __success,
+ memory_order __failure) _NOEXCEPT {
+ return __c11_atomic_compare_exchange_weak(
+ std::addressof(__a->__a_value),
+ __expected,
+ __value,
+ static_cast<__memory_order_underlying_t>(__success),
+ static_cast<__memory_order_underlying_t>(__to_failure_order(__failure)));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool __cxx_atomic_compare_exchange_weak(
+ __cxx_atomic_base_impl<_Tp>* __a, _Tp* __expected, _Tp __value, memory_order __success, memory_order __failure)
+ _NOEXCEPT {
+ return __c11_atomic_compare_exchange_weak(
+ std::addressof(__a->__a_value),
+ __expected,
+ __value,
+ static_cast<__memory_order_underlying_t>(__success),
+ static_cast<__memory_order_underlying_t>(__to_failure_order(__failure)));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_add(__cxx_atomic_base_impl<_Tp> volatile* __a, _Tp __delta, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_add(
+ std::addressof(__a->__a_value), __delta, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_add(__cxx_atomic_base_impl<_Tp>* __a, _Tp __delta, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_add(
+ std::addressof(__a->__a_value), __delta, static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp*
+__cxx_atomic_fetch_add(__cxx_atomic_base_impl<_Tp*> volatile* __a, ptrdiff_t __delta, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_add(
+ std::addressof(__a->__a_value), __delta, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp*
+__cxx_atomic_fetch_add(__cxx_atomic_base_impl<_Tp*>* __a, ptrdiff_t __delta, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_add(
+ std::addressof(__a->__a_value), __delta, static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_sub(__cxx_atomic_base_impl<_Tp> volatile* __a, _Tp __delta, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_sub(
+ std::addressof(__a->__a_value), __delta, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_sub(__cxx_atomic_base_impl<_Tp>* __a, _Tp __delta, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_sub(
+ std::addressof(__a->__a_value), __delta, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp*
+__cxx_atomic_fetch_sub(__cxx_atomic_base_impl<_Tp*> volatile* __a, ptrdiff_t __delta, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_sub(
+ std::addressof(__a->__a_value), __delta, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp*
+__cxx_atomic_fetch_sub(__cxx_atomic_base_impl<_Tp*>* __a, ptrdiff_t __delta, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_sub(
+ std::addressof(__a->__a_value), __delta, static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_and(__cxx_atomic_base_impl<_Tp> volatile* __a, _Tp __pattern, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_and(
+ std::addressof(__a->__a_value), __pattern, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_and(__cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_and(
+ std::addressof(__a->__a_value), __pattern, static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_or(__cxx_atomic_base_impl<_Tp> volatile* __a, _Tp __pattern, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_or(
+ std::addressof(__a->__a_value), __pattern, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_or(__cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_or(
+ std::addressof(__a->__a_value), __pattern, static_cast<__memory_order_underlying_t>(__order));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_xor(__cxx_atomic_base_impl<_Tp> volatile* __a, _Tp __pattern, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_xor(
+ std::addressof(__a->__a_value), __pattern, static_cast<__memory_order_underlying_t>(__order));
+}
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__cxx_atomic_fetch_xor(__cxx_atomic_base_impl<_Tp>* __a, _Tp __pattern, memory_order __order) _NOEXCEPT {
+ return __c11_atomic_fetch_xor(
+ std::addressof(__a->__a_value), __pattern, static_cast<__memory_order_underlying_t>(__order));
+}
+
+#endif // _LIBCPP_HAS_GCC_ATOMIC_IMP, _LIBCPP_HAS_C_ATOMIC_IMP
+
+template <typename _Tp, typename _Base = __cxx_atomic_base_impl<_Tp> >
+struct __cxx_atomic_impl : public _Base {
+ static_assert(is_trivially_copyable<_Tp>::value, "std::atomic<T> requires that 'T' be a trivially copyable type");
+
+ _LIBCPP_HIDE_FROM_ABI __cxx_atomic_impl() _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __cxx_atomic_impl(_Tp __value) _NOEXCEPT : _Base(__value) {}
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_CXX_ATOMIC_IMPL_H
diff --git a/libcxx/include/__cxx03/__atomic/fence.h b/libcxx/include/__cxx03/__atomic/fence.h
new file mode 100644
index 00000000000000..8c27ea54d62dd0
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/fence.h
@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_FENCE_H
+#define _LIBCPP___ATOMIC_FENCE_H
+
+#include <__atomic/cxx_atomic_impl.h>
+#include <__atomic/memory_order.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+inline _LIBCPP_HIDE_FROM_ABI void atomic_thread_fence(memory_order __m) _NOEXCEPT { __cxx_atomic_thread_fence(__m); }
+
+inline _LIBCPP_HIDE_FROM_ABI void atomic_signal_fence(memory_order __m) _NOEXCEPT { __cxx_atomic_signal_fence(__m); }
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_FENCE_H
diff --git a/libcxx/include/__cxx03/__atomic/is_always_lock_free.h b/libcxx/include/__cxx03/__atomic/is_always_lock_free.h
new file mode 100644
index 00000000000000..f928e79f70cea3
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/is_always_lock_free.h
@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_IS_ALWAYS_LOCK_FREE_H
+#define _LIBCPP___ATOMIC_IS_ALWAYS_LOCK_FREE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __libcpp_is_always_lock_free {
+ // __atomic_always_lock_free is available in all Standard modes
+ static const bool __value = __atomic_always_lock_free(sizeof(_Tp), nullptr);
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_IS_ALWAYS_LOCK_FREE_H
diff --git a/libcxx/include/__cxx03/__atomic/kill_dependency.h b/libcxx/include/__cxx03/__atomic/kill_dependency.h
new file mode 100644
index 00000000000000..103d52d35787fe
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/kill_dependency.h
@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_KILL_DEPENDENCY_H
+#define _LIBCPP___ATOMIC_KILL_DEPENDENCY_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp kill_dependency(_Tp __y) _NOEXCEPT {
+ return __y;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_KILL_DEPENDENCY_H
diff --git a/libcxx/include/__cxx03/__atomic/memory_order.h b/libcxx/include/__cxx03/__atomic/memory_order.h
new file mode 100644
index 00000000000000..294121d1c4e7f4
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/memory_order.h
@@ -0,0 +1,65 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_MEMORY_ORDER_H
+#define _LIBCPP___ATOMIC_MEMORY_ORDER_H
+
+#include <__config>
+#include <__type_traits/is_same.h>
+#include <__type_traits/underlying_type.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Figure out what the underlying type for `memory_order` would be if it were
+// declared as an unscoped enum (accounting for -fshort-enums). Use this result
+// to pin the underlying type in C++20.
+enum __legacy_memory_order { __mo_relaxed, __mo_consume, __mo_acquire, __mo_release, __mo_acq_rel, __mo_seq_cst };
+
+using __memory_order_underlying_t = underlying_type<__legacy_memory_order>::type;
+
+#if _LIBCPP_STD_VER >= 20
+
+enum class memory_order : __memory_order_underlying_t {
+ relaxed = __mo_relaxed,
+ consume = __mo_consume,
+ acquire = __mo_acquire,
+ release = __mo_release,
+ acq_rel = __mo_acq_rel,
+ seq_cst = __mo_seq_cst
+};
+
+static_assert(is_same<underlying_type<memory_order>::type, __memory_order_underlying_t>::value,
+ "unexpected underlying type for std::memory_order");
+
+inline constexpr auto memory_order_relaxed = memory_order::relaxed;
+inline constexpr auto memory_order_consume = memory_order::consume;
+inline constexpr auto memory_order_acquire = memory_order::acquire;
+inline constexpr auto memory_order_release = memory_order::release;
+inline constexpr auto memory_order_acq_rel = memory_order::acq_rel;
+inline constexpr auto memory_order_seq_cst = memory_order::seq_cst;
+
+#else
+
+enum memory_order {
+ memory_order_relaxed = __mo_relaxed,
+ memory_order_consume = __mo_consume,
+ memory_order_acquire = __mo_acquire,
+ memory_order_release = __mo_release,
+ memory_order_acq_rel = __mo_acq_rel,
+ memory_order_seq_cst = __mo_seq_cst,
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_MEMORY_ORDER_H
diff --git a/libcxx/include/__cxx03/__atomic/to_gcc_order.h b/libcxx/include/__cxx03/__atomic/to_gcc_order.h
new file mode 100644
index 00000000000000..d04c111addd314
--- /dev/null
+++ b/libcxx/include/__cxx03/__atomic/to_gcc_order.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ATOMIC_TO_GCC_ORDER_H
+#define _LIBCPP___ATOMIC_TO_GCC_ORDER_H
+
+#include <__atomic/memory_order.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if defined(__ATOMIC_RELAXED) && defined(__ATOMIC_CONSUME) && defined(__ATOMIC_ACQUIRE) && \
+ defined(__ATOMIC_RELEASE) && defined(__ATOMIC_ACQ_REL) && defined(__ATOMIC_SEQ_CST)
+
+_LIBCPP_HIDE_FROM_ABI inline _LIBCPP_CONSTEXPR int __to_gcc_order(memory_order __order) {
+ // Avoid switch statement to make this a constexpr.
+ return __order == memory_order_relaxed
+ ? __ATOMIC_RELAXED
+ : (__order == memory_order_acquire
+ ? __ATOMIC_ACQUIRE
+ : (__order == memory_order_release
+ ? __ATOMIC_RELEASE
+ : (__order == memory_order_seq_cst
+ ? __ATOMIC_SEQ_CST
+ : (__order == memory_order_acq_rel ? __ATOMIC_ACQ_REL : __ATOMIC_CONSUME))));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline _LIBCPP_CONSTEXPR int __to_gcc_failure_order(memory_order __order) {
+ // Avoid switch statement to make this a constexpr.
+ return __order == memory_order_relaxed
+ ? __ATOMIC_RELAXED
+ : (__order == memory_order_acquire
+ ? __ATOMIC_ACQUIRE
+ : (__order == memory_order_release
+ ? __ATOMIC_RELAXED
+ : (__order == memory_order_seq_cst
+ ? __ATOMIC_SEQ_CST
+ : (__order == memory_order_acq_rel ? __ATOMIC_ACQUIRE : __ATOMIC_CONSUME))));
+}
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ATOMIC_TO_GCC_ORDER_H
diff --git a/libcxx/include/__cxx03/__bit/bit_cast.h b/libcxx/include/__cxx03/__bit/bit_cast.h
new file mode 100644
index 00000000000000..cd045673817932
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/bit_cast.h
@@ -0,0 +1,44 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_BIT_CAST_H
+#define _LIBCPP___BIT_BIT_CAST_H
+
+#include <__config>
+#include <__type_traits/is_trivially_copyable.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _ToType, class _FromType>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI constexpr _ToType __bit_cast(const _FromType& __from) noexcept {
+ return __builtin_bit_cast(_ToType, __from);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _ToType, class _FromType>
+ requires(sizeof(_ToType) == sizeof(_FromType) && is_trivially_copyable_v<_ToType> &&
+ is_trivially_copyable_v<_FromType>)
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _ToType bit_cast(const _FromType& __from) noexcept {
+ return __builtin_bit_cast(_ToType, __from);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___BIT_BIT_CAST_H
diff --git a/libcxx/include/__cxx03/__bit/bit_ceil.h b/libcxx/include/__cxx03/__bit/bit_ceil.h
new file mode 100644
index 00000000000000..cfd792dc2e2adb
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/bit_ceil.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_BIT_CEIL_H
+#define _LIBCPP___BIT_BIT_CEIL_H
+
+#include <__assert>
+#include <__bit/countl.h>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp __bit_ceil(_Tp __t) noexcept {
+ if (__t < 2)
+ return 1;
+ const unsigned __n = numeric_limits<_Tp>::digits - std::__countl_zero((_Tp)(__t - 1u));
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(__n != numeric_limits<_Tp>::digits, "Bad input to bit_ceil");
+
+ if constexpr (sizeof(_Tp) >= sizeof(unsigned))
+ return _Tp{1} << __n;
+ else {
+ const unsigned __extra = numeric_limits<unsigned>::digits - numeric_limits<_Tp>::digits;
+ const unsigned __ret_val = 1u << (__n + __extra);
+ return (_Tp)(__ret_val >> __extra);
+ }
+}
+
+# if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp bit_ceil(_Tp __t) noexcept {
+ return std::__bit_ceil(__t);
+}
+
+# endif // _LIBCPP_STD_VER >= 20
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___BIT_BIT_CEIL_H
diff --git a/libcxx/include/__cxx03/__bit/bit_floor.h b/libcxx/include/__cxx03/__bit/bit_floor.h
new file mode 100644
index 00000000000000..133e369504e431
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/bit_floor.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_BIT_FLOOR_H
+#define _LIBCPP___BIT_BIT_FLOOR_H
+
+#include <__bit/bit_log2.h>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp bit_floor(_Tp __t) noexcept {
+ return __t == 0 ? 0 : _Tp{1} << std::__bit_log2(__t);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___BIT_BIT_FLOOR_H
diff --git a/libcxx/include/__cxx03/__bit/bit_log2.h b/libcxx/include/__cxx03/__bit/bit_log2.h
new file mode 100644
index 00000000000000..62936f67868600
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/bit_log2.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_BIT_LOG2_H
+#define _LIBCPP___BIT_BIT_LOG2_H
+
+#include <__bit/countl.h>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_unsigned_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp __bit_log2(_Tp __t) noexcept {
+ return numeric_limits<_Tp>::digits - 1 - std::countl_zero(__t);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___BIT_BIT_LOG2_H
diff --git a/libcxx/include/__cxx03/__bit/bit_width.h b/libcxx/include/__cxx03/__bit/bit_width.h
new file mode 100644
index 00000000000000..853e481776f7d2
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/bit_width.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_BIT_WIDTH_H
+#define _LIBCPP___BIT_BIT_WIDTH_H
+
+#include <__bit/bit_log2.h>
+#include <__concepts/arithmetic.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int bit_width(_Tp __t) noexcept {
+ return __t == 0 ? 0 : std::__bit_log2(__t) + 1;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___BIT_BIT_WIDTH_H
diff --git a/libcxx/include/__cxx03/__bit/blsr.h b/libcxx/include/__cxx03/__bit/blsr.h
new file mode 100644
index 00000000000000..76bd521f5c3071
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/blsr.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_BLSR_H
+#define _LIBCPP___BIT_BLSR_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unsigned __libcpp_blsr(unsigned __x) _NOEXCEPT {
+ return __x ^ (__x & -__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unsigned long __libcpp_blsr(unsigned long __x) _NOEXCEPT {
+ return __x ^ (__x & -__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unsigned long long __libcpp_blsr(unsigned long long __x) _NOEXCEPT {
+ return __x ^ (__x & -__x);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___BIT_BLSR_H
diff --git a/libcxx/include/__cxx03/__bit/byteswap.h b/libcxx/include/__cxx03/__bit/byteswap.h
new file mode 100644
index 00000000000000..6225ecf2f92dfb
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/byteswap.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_BYTESWAP_H
+#define _LIBCPP___BIT_BYTESWAP_H
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <integral _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp byteswap(_Tp __val) noexcept {
+ if constexpr (sizeof(_Tp) == 1) {
+ return __val;
+ } else if constexpr (sizeof(_Tp) == 2) {
+ return __builtin_bswap16(__val);
+ } else if constexpr (sizeof(_Tp) == 4) {
+ return __builtin_bswap32(__val);
+ } else if constexpr (sizeof(_Tp) == 8) {
+ return __builtin_bswap64(__val);
+# ifndef _LIBCPP_HAS_NO_INT128
+ } else if constexpr (sizeof(_Tp) == 16) {
+# if __has_builtin(__builtin_bswap128)
+ return __builtin_bswap128(__val);
+# else
+ return static_cast<_Tp>(byteswap(static_cast<uint64_t>(__val))) << 64 |
+ static_cast<_Tp>(byteswap(static_cast<uint64_t>(__val >> 64)));
+# endif // __has_builtin(__builtin_bswap128)
+# endif // _LIBCPP_HAS_NO_INT128
+ } else {
+ static_assert(sizeof(_Tp) == 0, "byteswap is unimplemented for integral types of this size");
+ }
+}
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___BIT_BYTESWAP_H
diff --git a/libcxx/include/__cxx03/__bit/countl.h b/libcxx/include/__cxx03/__bit/countl.h
new file mode 100644
index 00000000000000..998a0b44c19dcb
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/countl.h
@@ -0,0 +1,113 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// TODO: __builtin_clzg is available since Clang 19 and GCC 14. When support for older versions is dropped, we can
+// refactor this code to exclusively use __builtin_clzg.
+
+#ifndef _LIBCPP___BIT_COUNTL_H
+#define _LIBCPP___BIT_COUNTL_H
+
+#include <__bit/rotate.h>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__type_traits/is_unsigned_integer.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_clz(unsigned __x) _NOEXCEPT {
+ return __builtin_clz(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_clz(unsigned long __x) _NOEXCEPT {
+ return __builtin_clzl(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_clz(unsigned long long __x) _NOEXCEPT {
+ return __builtin_clzll(__x);
+}
+
+#ifndef _LIBCPP_HAS_NO_INT128
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_clz(__uint128_t __x) _NOEXCEPT {
+# if __has_builtin(__builtin_clzg)
+ return __builtin_clzg(__x);
+# else
+ // The function is written in this form due to C++ constexpr limitations.
+ // The algorithm:
+ // - Test whether any bit in the high 64-bits is set
+ // - No bits set:
+ // - The high 64-bits contain 64 leading zeros,
+ // - Add the result of the low 64-bits.
+ // - Any bits set:
+ // - The number of leading zeros of the input is the number of leading
+ // zeros in the high 64-bits.
+ return ((__x >> 64) == 0) ? (64 + __builtin_clzll(static_cast<unsigned long long>(__x)))
+ : __builtin_clzll(static_cast<unsigned long long>(__x >> 64));
+# endif
+}
+#endif // _LIBCPP_HAS_NO_INT128
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int __countl_zero(_Tp __t) _NOEXCEPT {
+ static_assert(__libcpp_is_unsigned_integer<_Tp>::value, "__countl_zero requires an unsigned integer type");
+#if __has_builtin(__builtin_clzg)
+ return __builtin_clzg(__t, numeric_limits<_Tp>::digits);
+#else // __has_builtin(__builtin_clzg)
+ if (__t == 0)
+ return numeric_limits<_Tp>::digits;
+
+ if (sizeof(_Tp) <= sizeof(unsigned int))
+ return std::__libcpp_clz(static_cast<unsigned int>(__t)) -
+ (numeric_limits<unsigned int>::digits - numeric_limits<_Tp>::digits);
+ else if (sizeof(_Tp) <= sizeof(unsigned long))
+ return std::__libcpp_clz(static_cast<unsigned long>(__t)) -
+ (numeric_limits<unsigned long>::digits - numeric_limits<_Tp>::digits);
+ else if (sizeof(_Tp) <= sizeof(unsigned long long))
+ return std::__libcpp_clz(static_cast<unsigned long long>(__t)) -
+ (numeric_limits<unsigned long long>::digits - numeric_limits<_Tp>::digits);
+ else {
+ int __ret = 0;
+ int __iter = 0;
+ const unsigned int __ulldigits = numeric_limits<unsigned long long>::digits;
+ while (true) {
+ __t = std::__rotl(__t, __ulldigits);
+ if ((__iter = std::__countl_zero(static_cast<unsigned long long>(__t))) != __ulldigits)
+ break;
+ __ret += __iter;
+ }
+ return __ret + __iter;
+ }
+#endif // __has_builtin(__builtin_clzg)
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int countl_zero(_Tp __t) noexcept {
+ return std::__countl_zero(__t);
+}
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int countl_one(_Tp __t) noexcept {
+ return __t != numeric_limits<_Tp>::max() ? std::countl_zero(static_cast<_Tp>(~__t)) : numeric_limits<_Tp>::digits;
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___BIT_COUNTL_H
diff --git a/libcxx/include/__cxx03/__bit/countr.h b/libcxx/include/__cxx03/__bit/countr.h
new file mode 100644
index 00000000000000..9e92021fba3551
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/countr.h
@@ -0,0 +1,84 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// TODO: __builtin_ctzg is available since Clang 19 and GCC 14. When support for older versions is dropped, we can
+// refactor this code to exclusively use __builtin_ctzg.
+
+#ifndef _LIBCPP___BIT_COUNTR_H
+#define _LIBCPP___BIT_COUNTR_H
+
+#include <__bit/rotate.h>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_ctz(unsigned __x) _NOEXCEPT {
+ return __builtin_ctz(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_ctz(unsigned long __x) _NOEXCEPT {
+ return __builtin_ctzl(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_ctz(unsigned long long __x) _NOEXCEPT {
+ return __builtin_ctzll(__x);
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int __countr_zero(_Tp __t) _NOEXCEPT {
+#if __has_builtin(__builtin_ctzg)
+ return __builtin_ctzg(__t, numeric_limits<_Tp>::digits);
+#else // __has_builtin(__builtin_ctzg)
+ if (__t == 0)
+ return numeric_limits<_Tp>::digits;
+ if (sizeof(_Tp) <= sizeof(unsigned int))
+ return std::__libcpp_ctz(static_cast<unsigned int>(__t));
+ else if (sizeof(_Tp) <= sizeof(unsigned long))
+ return std::__libcpp_ctz(static_cast<unsigned long>(__t));
+ else if (sizeof(_Tp) <= sizeof(unsigned long long))
+ return std::__libcpp_ctz(static_cast<unsigned long long>(__t));
+ else {
+ int __ret = 0;
+ const unsigned int __ulldigits = numeric_limits<unsigned long long>::digits;
+ while (static_cast<unsigned long long>(__t) == 0uLL) {
+ __ret += __ulldigits;
+ __t >>= __ulldigits;
+ }
+ return __ret + std::__libcpp_ctz(static_cast<unsigned long long>(__t));
+ }
+#endif // __has_builtin(__builtin_ctzg)
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int countr_zero(_Tp __t) noexcept {
+ return std::__countr_zero(__t);
+}
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int countr_one(_Tp __t) noexcept {
+ return __t != numeric_limits<_Tp>::max() ? std::countr_zero(static_cast<_Tp>(~__t)) : numeric_limits<_Tp>::digits;
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___BIT_COUNTR_H
diff --git a/libcxx/include/__cxx03/__bit/endian.h b/libcxx/include/__cxx03/__bit/endian.h
new file mode 100644
index 00000000000000..2d31e5ddff4f1f
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/endian.h
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_ENDIAN_H
+#define _LIBCPP___BIT_ENDIAN_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+enum class endian {
+ little = 0xDEAD,
+ big = 0xFACE,
+# if defined(_LIBCPP_LITTLE_ENDIAN)
+ native = little
+# elif defined(_LIBCPP_BIG_ENDIAN)
+ native = big
+# else
+ native = 0xCAFE
+# endif
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___BIT_ENDIAN_H
diff --git a/libcxx/include/__cxx03/__bit/has_single_bit.h b/libcxx/include/__cxx03/__bit/has_single_bit.h
new file mode 100644
index 00000000000000..52f5853a1bc8a4
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/has_single_bit.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_HAS_SINGLE_BIT_H
+#define _LIBCPP___BIT_HAS_SINGLE_BIT_H
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool has_single_bit(_Tp __t) noexcept {
+ return __t != 0 && (((__t & (__t - 1)) == 0));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___BIT_HAS_SINGLE_BIT_H
diff --git a/libcxx/include/__cxx03/__bit/invert_if.h b/libcxx/include/__cxx03/__bit/invert_if.h
new file mode 100644
index 00000000000000..f7606ede26da00
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/invert_if.h
@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_INVERT_IF_H
+#define _LIBCPP___BIT_INVERT_IF_H
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <bool _Invert, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp __invert_if(_Tp __v) {
+ if (_Invert)
+ return ~__v;
+ return __v;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___BIT_INVERT_IF_H
diff --git a/libcxx/include/__cxx03/__bit/popcount.h b/libcxx/include/__cxx03/__bit/popcount.h
new file mode 100644
index 00000000000000..5cf0a01d073382
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/popcount.h
@@ -0,0 +1,71 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// TODO: __builtin_popcountg is available since Clang 19 and GCC 14. When support for older versions is dropped, we can
+// refactor this code to exclusively use __builtin_popcountg.
+
+#ifndef _LIBCPP___BIT_POPCOUNT_H
+#define _LIBCPP___BIT_POPCOUNT_H
+
+#include <__bit/rotate.h>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_popcount(unsigned __x) _NOEXCEPT {
+ return __builtin_popcount(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_popcount(unsigned long __x) _NOEXCEPT {
+ return __builtin_popcountl(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_popcount(unsigned long long __x) _NOEXCEPT {
+ return __builtin_popcountll(__x);
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int popcount(_Tp __t) noexcept {
+# if __has_builtin(__builtin_popcountg)
+ return __builtin_popcountg(__t);
+# else // __has_builtin(__builtin_popcountg)
+ if (sizeof(_Tp) <= sizeof(unsigned int))
+ return std::__libcpp_popcount(static_cast<unsigned int>(__t));
+ else if (sizeof(_Tp) <= sizeof(unsigned long))
+ return std::__libcpp_popcount(static_cast<unsigned long>(__t));
+ else if (sizeof(_Tp) <= sizeof(unsigned long long))
+ return std::__libcpp_popcount(static_cast<unsigned long long>(__t));
+ else {
+ int __ret = 0;
+ while (__t != 0) {
+ __ret += std::__libcpp_popcount(static_cast<unsigned long long>(__t));
+ __t >>= numeric_limits<unsigned long long>::digits;
+ }
+ return __ret;
+ }
+# endif // __has_builtin(__builtin_popcountg)
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___BIT_POPCOUNT_H
diff --git a/libcxx/include/__cxx03/__bit/rotate.h b/libcxx/include/__cxx03/__bit/rotate.h
new file mode 100644
index 00000000000000..90e430e9d04256
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit/rotate.h
@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_ROTATE_H
+#define _LIBCPP___BIT_ROTATE_H
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__type_traits/is_unsigned_integer.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Writing two full functions for rotl and rotr makes it easier for the compiler
+// to optimize the code. On x86 this function becomes the ROL instruction and
+// the rotr function becomes the ROR instruction.
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp __rotl(_Tp __x, int __s) _NOEXCEPT {
+ static_assert(__libcpp_is_unsigned_integer<_Tp>::value, "__rotl requires an unsigned integer type");
+ const int __N = numeric_limits<_Tp>::digits;
+ int __r = __s % __N;
+
+ if (__r == 0)
+ return __x;
+
+ if (__r > 0)
+ return (__x << __r) | (__x >> (__N - __r));
+
+ return (__x >> -__r) | (__x << (__N + __r));
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp __rotr(_Tp __x, int __s) _NOEXCEPT {
+ static_assert(__libcpp_is_unsigned_integer<_Tp>::value, "__rotr requires an unsigned integer type");
+ const int __N = numeric_limits<_Tp>::digits;
+ int __r = __s % __N;
+
+ if (__r == 0)
+ return __x;
+
+ if (__r > 0)
+ return (__x >> __r) | (__x << (__N - __r));
+
+ return (__x << -__r) | (__x >> (__N + __r));
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp rotl(_Tp __t, int __cnt) noexcept {
+ return std::__rotl(__t, __cnt);
+}
+
+template <__libcpp_unsigned_integer _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp rotr(_Tp __t, int __cnt) noexcept {
+ return std::__rotr(__t, __cnt);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___BIT_ROTATE_H
diff --git a/libcxx/include/__cxx03/__bit_reference b/libcxx/include/__cxx03/__bit_reference
new file mode 100644
index 00000000000000..22637d43974123
--- /dev/null
+++ b/libcxx/include/__cxx03/__bit_reference
@@ -0,0 +1,1024 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___BIT_REFERENCE
+#define _LIBCPP___BIT_REFERENCE
+
+#include <__algorithm/copy_n.h>
+#include <__algorithm/fill_n.h>
+#include <__algorithm/min.h>
+#include <__bit/countr.h>
+#include <__bit/invert_if.h>
+#include <__bit/popcount.h>
+#include <__compare/ordering.h>
+#include <__config>
+#include <__fwd/bit_reference.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/construct_at.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/conditional.h>
+#include <__utility/swap.h>
+#include <cstring>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Cp>
+class __bit_const_reference;
+
+template <class _Tp>
+struct __has_storage_type {
+ static const bool value = false;
+};
+
+template <class _Cp, bool = __has_storage_type<_Cp>::value>
+class __bit_reference {
+ using __storage_type = typename _Cp::__storage_type;
+ using __storage_pointer = typename _Cp::__storage_pointer;
+
+ __storage_pointer __seg_;
+ __storage_type __mask_;
+
+ friend typename _Cp::__self;
+
+ friend class __bit_const_reference<_Cp>;
+ friend class __bit_iterator<_Cp, false>;
+
+public:
+ using __container = typename _Cp::__self;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_reference(const __bit_reference&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 operator bool() const _NOEXCEPT {
+ return static_cast<bool>(*__seg_ & __mask_);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool operator~() const _NOEXCEPT {
+ return !static_cast<bool>(*this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_reference& operator=(bool __x) _NOEXCEPT {
+ if (__x)
+ *__seg_ |= __mask_;
+ else
+ *__seg_ &= ~__mask_;
+ return *this;
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI constexpr const __bit_reference& operator=(bool __x) const noexcept {
+ if (__x)
+ *__seg_ |= __mask_;
+ else
+ *__seg_ &= ~__mask_;
+ return *this;
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_reference& operator=(const __bit_reference& __x) _NOEXCEPT {
+ return operator=(static_cast<bool>(__x));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void flip() _NOEXCEPT { *__seg_ ^= __mask_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cp, false> operator&() const _NOEXCEPT {
+ return __bit_iterator<_Cp, false>(__seg_, static_cast<unsigned>(std::__libcpp_ctz(__mask_)));
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit __bit_reference(__storage_pointer __s, __storage_type __m) _NOEXCEPT
+ : __seg_(__s),
+ __mask_(__m) {}
+};
+
+template <class _Cp>
+class __bit_reference<_Cp, false> {};
+
+template <class _Cp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+swap(__bit_reference<_Cp> __x, __bit_reference<_Cp> __y) _NOEXCEPT {
+ bool __t = __x;
+ __x = __y;
+ __y = __t;
+}
+
+template <class _Cp, class _Dp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+swap(__bit_reference<_Cp> __x, __bit_reference<_Dp> __y) _NOEXCEPT {
+ bool __t = __x;
+ __x = __y;
+ __y = __t;
+}
+
+template <class _Cp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(__bit_reference<_Cp> __x, bool& __y) _NOEXCEPT {
+ bool __t = __x;
+ __x = __y;
+ __y = __t;
+}
+
+template <class _Cp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(bool& __x, __bit_reference<_Cp> __y) _NOEXCEPT {
+ bool __t = __x;
+ __x = __y;
+ __y = __t;
+}
+
+template <class _Cp>
+class __bit_const_reference {
+ using __storage_type = typename _Cp::__storage_type;
+ using __storage_pointer = typename _Cp::__const_storage_pointer;
+
+ __storage_pointer __seg_;
+ __storage_type __mask_;
+
+ friend typename _Cp::__self;
+ friend class __bit_iterator<_Cp, true>;
+
+public:
+ using __container = typename _Cp::__self;
+
+ _LIBCPP_HIDE_FROM_ABI __bit_const_reference(const __bit_const_reference&) = default;
+ __bit_const_reference& operator=(const __bit_const_reference&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_const_reference(const __bit_reference<_Cp>& __x) _NOEXCEPT
+ : __seg_(__x.__seg_),
+ __mask_(__x.__mask_) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR operator bool() const _NOEXCEPT {
+ return static_cast<bool>(*__seg_ & __mask_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cp, true> operator&() const _NOEXCEPT {
+ return __bit_iterator<_Cp, true>(__seg_, static_cast<unsigned>(std::__libcpp_ctz(__mask_)));
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR explicit __bit_const_reference(__storage_pointer __s, __storage_type __m) _NOEXCEPT
+ : __seg_(__s),
+ __mask_(__m) {}
+};
+
+// copy
+
+template <class _Cp, bool _IsConst>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_aligned(
+ __bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, __bit_iterator<_Cp, false> __result) {
+ using _In = __bit_iterator<_Cp, _IsConst>;
+ using difference_type = typename _In::difference_type;
+ using __storage_type = typename _In::__storage_type;
+
+ const int __bits_per_word = _In::__bits_per_word;
+ difference_type __n = __last - __first;
+ if (__n > 0) {
+ // do first word
+ if (__first.__ctz_ != 0) {
+ unsigned __clz = __bits_per_word - __first.__ctz_;
+ difference_type __dn = std::min(static_cast<difference_type>(__clz), __n);
+ __n -= __dn;
+ __storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz - __dn));
+ __storage_type __b = *__first.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b;
+ __result.__seg_ += (__dn + __result.__ctz_) / __bits_per_word;
+ __result.__ctz_ = static_cast<unsigned>((__dn + __result.__ctz_) % __bits_per_word);
+ ++__first.__seg_;
+ // __first.__ctz_ = 0;
+ }
+ // __first.__ctz_ == 0;
+ // do middle words
+ __storage_type __nw = __n / __bits_per_word;
+ std::copy_n(std::__to_address(__first.__seg_), __nw, std::__to_address(__result.__seg_));
+ __n -= __nw * __bits_per_word;
+ __result.__seg_ += __nw;
+ // do last word
+ if (__n > 0) {
+ __first.__seg_ += __nw;
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __storage_type __b = *__first.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b;
+ __result.__ctz_ = static_cast<unsigned>(__n);
+ }
+ }
+ return __result;
+}
+
+template <class _Cp, bool _IsConst>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_unaligned(
+ __bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, __bit_iterator<_Cp, false> __result) {
+ using _In = __bit_iterator<_Cp, _IsConst>;
+ using difference_type = typename _In::difference_type;
+ using __storage_type = typename _In::__storage_type;
+
+ const int __bits_per_word = _In::__bits_per_word;
+ difference_type __n = __last - __first;
+ if (__n > 0) {
+ // do first word
+ if (__first.__ctz_ != 0) {
+ unsigned __clz_f = __bits_per_word - __first.__ctz_;
+ difference_type __dn = std::min(static_cast<difference_type>(__clz_f), __n);
+ __n -= __dn;
+ __storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
+ __storage_type __b = *__first.__seg_ & __m;
+ unsigned __clz_r = __bits_per_word - __result.__ctz_;
+ __storage_type __ddn = std::min<__storage_type>(__dn, __clz_r);
+ __m = (~__storage_type(0) << __result.__ctz_) & (~__storage_type(0) >> (__clz_r - __ddn));
+ *__result.__seg_ &= ~__m;
+ if (__result.__ctz_ > __first.__ctz_)
+ *__result.__seg_ |= __b << (__result.__ctz_ - __first.__ctz_);
+ else
+ *__result.__seg_ |= __b >> (__first.__ctz_ - __result.__ctz_);
+ __result.__seg_ += (__ddn + __result.__ctz_) / __bits_per_word;
+ __result.__ctz_ = static_cast<unsigned>((__ddn + __result.__ctz_) % __bits_per_word);
+ __dn -= __ddn;
+ if (__dn > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __dn);
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b >> (__first.__ctz_ + __ddn);
+ __result.__ctz_ = static_cast<unsigned>(__dn);
+ }
+ ++__first.__seg_;
+ // __first.__ctz_ = 0;
+ }
+ // __first.__ctz_ == 0;
+ // do middle words
+ unsigned __clz_r = __bits_per_word - __result.__ctz_;
+ __storage_type __m = ~__storage_type(0) << __result.__ctz_;
+ for (; __n >= __bits_per_word; __n -= __bits_per_word, ++__first.__seg_) {
+ __storage_type __b = *__first.__seg_;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b << __result.__ctz_;
+ ++__result.__seg_;
+ *__result.__seg_ &= __m;
+ *__result.__seg_ |= __b >> __clz_r;
+ }
+ // do last word
+ if (__n > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __storage_type __b = *__first.__seg_ & __m;
+ __storage_type __dn = std::min(__n, static_cast<difference_type>(__clz_r));
+ __m = (~__storage_type(0) << __result.__ctz_) & (~__storage_type(0) >> (__clz_r - __dn));
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b << __result.__ctz_;
+ __result.__seg_ += (__dn + __result.__ctz_) / __bits_per_word;
+ __result.__ctz_ = static_cast<unsigned>((__dn + __result.__ctz_) % __bits_per_word);
+ __n -= __dn;
+ if (__n > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b >> __dn;
+ __result.__ctz_ = static_cast<unsigned>(__n);
+ }
+ }
+ }
+ return __result;
+}
+
+template <class _Cp, bool _IsConst>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cp, false>
+copy(__bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, __bit_iterator<_Cp, false> __result) {
+ if (__first.__ctz_ == __result.__ctz_)
+ return std::__copy_aligned(__first, __last, __result);
+ return std::__copy_unaligned(__first, __last, __result);
+}
+
+// copy_backward
+
+template <class _Cp, bool _IsConst>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_aligned(
+ __bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, __bit_iterator<_Cp, false> __result) {
+ using _In = __bit_iterator<_Cp, _IsConst>;
+ using difference_type = typename _In::difference_type;
+ using __storage_type = typename _In::__storage_type;
+
+ const int __bits_per_word = _In::__bits_per_word;
+ difference_type __n = __last - __first;
+ if (__n > 0) {
+ // do first word
+ if (__last.__ctz_ != 0) {
+ difference_type __dn = std::min(static_cast<difference_type>(__last.__ctz_), __n);
+ __n -= __dn;
+ unsigned __clz = __bits_per_word - __last.__ctz_;
+ __storage_type __m = (~__storage_type(0) << (__last.__ctz_ - __dn)) & (~__storage_type(0) >> __clz);
+ __storage_type __b = *__last.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b;
+ __result.__ctz_ = static_cast<unsigned>(((-__dn & (__bits_per_word - 1)) + __result.__ctz_) % __bits_per_word);
+ // __last.__ctz_ = 0
+ }
+ // __last.__ctz_ == 0 || __n == 0
+ // __result.__ctz_ == 0 || __n == 0
+ // do middle words
+ __storage_type __nw = __n / __bits_per_word;
+ __result.__seg_ -= __nw;
+ __last.__seg_ -= __nw;
+ std::copy_n(std::__to_address(__last.__seg_), __nw, std::__to_address(__result.__seg_));
+ __n -= __nw * __bits_per_word;
+ // do last word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) << (__bits_per_word - __n);
+ __storage_type __b = *--__last.__seg_ & __m;
+ *--__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b;
+ __result.__ctz_ = static_cast<unsigned>(-__n & (__bits_per_word - 1));
+ }
+ }
+ return __result;
+}
+
+template <class _Cp, bool _IsConst>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_unaligned(
+ __bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, __bit_iterator<_Cp, false> __result) {
+ using _In = __bit_iterator<_Cp, _IsConst>;
+ using difference_type = typename _In::difference_type;
+ using __storage_type = typename _In::__storage_type;
+
+ const int __bits_per_word = _In::__bits_per_word;
+ difference_type __n = __last - __first;
+ if (__n > 0) {
+ // do first word
+ if (__last.__ctz_ != 0) {
+ difference_type __dn = std::min(static_cast<difference_type>(__last.__ctz_), __n);
+ __n -= __dn;
+ unsigned __clz_l = __bits_per_word - __last.__ctz_;
+ __storage_type __m = (~__storage_type(0) << (__last.__ctz_ - __dn)) & (~__storage_type(0) >> __clz_l);
+ __storage_type __b = *__last.__seg_ & __m;
+ unsigned __clz_r = __bits_per_word - __result.__ctz_;
+ __storage_type __ddn = std::min(__dn, static_cast<difference_type>(__result.__ctz_));
+ if (__ddn > 0) {
+ __m = (~__storage_type(0) << (__result.__ctz_ - __ddn)) & (~__storage_type(0) >> __clz_r);
+ *__result.__seg_ &= ~__m;
+ if (__result.__ctz_ > __last.__ctz_)
+ *__result.__seg_ |= __b << (__result.__ctz_ - __last.__ctz_);
+ else
+ *__result.__seg_ |= __b >> (__last.__ctz_ - __result.__ctz_);
+ __result.__ctz_ = static_cast<unsigned>(((-__ddn & (__bits_per_word - 1)) + __result.__ctz_) % __bits_per_word);
+ __dn -= __ddn;
+ }
+ if (__dn > 0) {
+ // __result.__ctz_ == 0
+ --__result.__seg_;
+ __result.__ctz_ = static_cast<unsigned>(-__dn & (__bits_per_word - 1));
+ __m = ~__storage_type(0) << __result.__ctz_;
+ *__result.__seg_ &= ~__m;
+ __last.__ctz_ -= __dn + __ddn;
+ *__result.__seg_ |= __b << (__result.__ctz_ - __last.__ctz_);
+ }
+ // __last.__ctz_ = 0
+ }
+ // __last.__ctz_ == 0 || __n == 0
+ // __result.__ctz_ != 0 || __n == 0
+ // do middle words
+ unsigned __clz_r = __bits_per_word - __result.__ctz_;
+ __storage_type __m = ~__storage_type(0) >> __clz_r;
+ for (; __n >= __bits_per_word; __n -= __bits_per_word) {
+ __storage_type __b = *--__last.__seg_;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b >> __clz_r;
+ *--__result.__seg_ &= __m;
+ *__result.__seg_ |= __b << __result.__ctz_;
+ }
+ // do last word
+ if (__n > 0) {
+ __m = ~__storage_type(0) << (__bits_per_word - __n);
+ __storage_type __b = *--__last.__seg_ & __m;
+ __clz_r = __bits_per_word - __result.__ctz_;
+ __storage_type __dn = std::min(__n, static_cast<difference_type>(__result.__ctz_));
+ __m = (~__storage_type(0) << (__result.__ctz_ - __dn)) & (~__storage_type(0) >> __clz_r);
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b >> (__bits_per_word - __result.__ctz_);
+ __result.__ctz_ = static_cast<unsigned>(((-__dn & (__bits_per_word - 1)) + __result.__ctz_) % __bits_per_word);
+ __n -= __dn;
+ if (__n > 0) {
+ // __result.__ctz_ == 0
+ --__result.__seg_;
+ __result.__ctz_ = static_cast<unsigned>(-__n & (__bits_per_word - 1));
+ __m = ~__storage_type(0) << __result.__ctz_;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b << (__result.__ctz_ - (__bits_per_word - __n - __dn));
+ }
+ }
+ }
+ return __result;
+}
+
+template <class _Cp, bool _IsConst>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cp, false> copy_backward(
+ __bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, __bit_iterator<_Cp, false> __result) {
+ if (__last.__ctz_ == __result.__ctz_)
+ return std::__copy_backward_aligned(__first, __last, __result);
+ return std::__copy_backward_unaligned(__first, __last, __result);
+}
+
+// move
+
+template <class _Cp, bool _IsConst>
+inline _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false>
+move(__bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, __bit_iterator<_Cp, false> __result) {
+ return std::copy(__first, __last, __result);
+}
+
+// move_backward
+
+template <class _Cp, bool _IsConst>
+inline _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> move_backward(
+ __bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsConst> __last, __bit_iterator<_Cp, false> __result) {
+ return std::copy_backward(__first, __last, __result);
+}
+
+// swap_ranges
+
+template <class _Cl, class _Cr>
+_LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cr, false> __swap_ranges_aligned(
+ __bit_iterator<_Cl, false> __first, __bit_iterator<_Cl, false> __last, __bit_iterator<_Cr, false> __result) {
+ using _I1 = __bit_iterator<_Cl, false>;
+ using difference_type = typename _I1::difference_type;
+ using __storage_type = typename _I1::__storage_type;
+
+ const int __bits_per_word = _I1::__bits_per_word;
+ difference_type __n = __last - __first;
+ if (__n > 0) {
+ // do first word
+ if (__first.__ctz_ != 0) {
+ unsigned __clz = __bits_per_word - __first.__ctz_;
+ difference_type __dn = std::min(static_cast<difference_type>(__clz), __n);
+ __n -= __dn;
+ __storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz - __dn));
+ __storage_type __b1 = *__first.__seg_ & __m;
+ *__first.__seg_ &= ~__m;
+ __storage_type __b2 = *__result.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b1;
+ *__first.__seg_ |= __b2;
+ __result.__seg_ += (__dn + __result.__ctz_) / __bits_per_word;
+ __result.__ctz_ = static_cast<unsigned>((__dn + __result.__ctz_) % __bits_per_word);
+ ++__first.__seg_;
+ // __first.__ctz_ = 0;
+ }
+ // __first.__ctz_ == 0;
+ // do middle words
+ for (; __n >= __bits_per_word; __n -= __bits_per_word, ++__first.__seg_, ++__result.__seg_)
+ swap(*__first.__seg_, *__result.__seg_);
+ // do last word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __storage_type __b1 = *__first.__seg_ & __m;
+ *__first.__seg_ &= ~__m;
+ __storage_type __b2 = *__result.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b1;
+ *__first.__seg_ |= __b2;
+ __result.__ctz_ = static_cast<unsigned>(__n);
+ }
+ }
+ return __result;
+}
+
+template <class _Cl, class _Cr>
+_LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cr, false> __swap_ranges_unaligned(
+ __bit_iterator<_Cl, false> __first, __bit_iterator<_Cl, false> __last, __bit_iterator<_Cr, false> __result) {
+ using _I1 = __bit_iterator<_Cl, false>;
+ using difference_type = typename _I1::difference_type;
+ using __storage_type = typename _I1::__storage_type;
+
+ const int __bits_per_word = _I1::__bits_per_word;
+ difference_type __n = __last - __first;
+ if (__n > 0) {
+ // do first word
+ if (__first.__ctz_ != 0) {
+ unsigned __clz_f = __bits_per_word - __first.__ctz_;
+ difference_type __dn = std::min(static_cast<difference_type>(__clz_f), __n);
+ __n -= __dn;
+ __storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
+ __storage_type __b1 = *__first.__seg_ & __m;
+ *__first.__seg_ &= ~__m;
+ unsigned __clz_r = __bits_per_word - __result.__ctz_;
+ __storage_type __ddn = std::min<__storage_type>(__dn, __clz_r);
+ __m = (~__storage_type(0) << __result.__ctz_) & (~__storage_type(0) >> (__clz_r - __ddn));
+ __storage_type __b2 = *__result.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ if (__result.__ctz_ > __first.__ctz_) {
+ unsigned __s = __result.__ctz_ - __first.__ctz_;
+ *__result.__seg_ |= __b1 << __s;
+ *__first.__seg_ |= __b2 >> __s;
+ } else {
+ unsigned __s = __first.__ctz_ - __result.__ctz_;
+ *__result.__seg_ |= __b1 >> __s;
+ *__first.__seg_ |= __b2 << __s;
+ }
+ __result.__seg_ += (__ddn + __result.__ctz_) / __bits_per_word;
+ __result.__ctz_ = static_cast<unsigned>((__ddn + __result.__ctz_) % __bits_per_word);
+ __dn -= __ddn;
+ if (__dn > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __dn);
+ __b2 = *__result.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ unsigned __s = __first.__ctz_ + __ddn;
+ *__result.__seg_ |= __b1 >> __s;
+ *__first.__seg_ |= __b2 << __s;
+ __result.__ctz_ = static_cast<unsigned>(__dn);
+ }
+ ++__first.__seg_;
+ // __first.__ctz_ = 0;
+ }
+ // __first.__ctz_ == 0;
+ // do middle words
+ __storage_type __m = ~__storage_type(0) << __result.__ctz_;
+ unsigned __clz_r = __bits_per_word - __result.__ctz_;
+ for (; __n >= __bits_per_word; __n -= __bits_per_word, ++__first.__seg_) {
+ __storage_type __b1 = *__first.__seg_;
+ __storage_type __b2 = *__result.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b1 << __result.__ctz_;
+ *__first.__seg_ = __b2 >> __result.__ctz_;
+ ++__result.__seg_;
+ __b2 = *__result.__seg_ & ~__m;
+ *__result.__seg_ &= __m;
+ *__result.__seg_ |= __b1 >> __clz_r;
+ *__first.__seg_ |= __b2 << __clz_r;
+ }
+ // do last word
+ if (__n > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __storage_type __b1 = *__first.__seg_ & __m;
+ *__first.__seg_ &= ~__m;
+ __storage_type __dn = std::min<__storage_type>(__n, __clz_r);
+ __m = (~__storage_type(0) << __result.__ctz_) & (~__storage_type(0) >> (__clz_r - __dn));
+ __storage_type __b2 = *__result.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b1 << __result.__ctz_;
+ *__first.__seg_ |= __b2 >> __result.__ctz_;
+ __result.__seg_ += (__dn + __result.__ctz_) / __bits_per_word;
+ __result.__ctz_ = static_cast<unsigned>((__dn + __result.__ctz_) % __bits_per_word);
+ __n -= __dn;
+ if (__n > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __b2 = *__result.__seg_ & __m;
+ *__result.__seg_ &= ~__m;
+ *__result.__seg_ |= __b1 >> __dn;
+ *__first.__seg_ |= __b2 << __dn;
+ __result.__ctz_ = static_cast<unsigned>(__n);
+ }
+ }
+ }
+ return __result;
+}
+
+template <class _Cl, class _Cr>
+inline _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cr, false> swap_ranges(
+ __bit_iterator<_Cl, false> __first1, __bit_iterator<_Cl, false> __last1, __bit_iterator<_Cr, false> __first2) {
+ if (__first1.__ctz_ == __first2.__ctz_)
+ return std::__swap_ranges_aligned(__first1, __last1, __first2);
+ return std::__swap_ranges_unaligned(__first1, __last1, __first2);
+}
+
+// rotate
+
+template <class _Cp>
+struct __bit_array {
+ using difference_type = typename _Cp::difference_type;
+ using __storage_type = typename _Cp::__storage_type;
+ using __storage_pointer = typename _Cp::__storage_pointer;
+ using iterator = typename _Cp::iterator;
+
+ static const unsigned __bits_per_word = _Cp::__bits_per_word;
+ static const unsigned _Np = 4;
+
+ difference_type __size_;
+ __storage_type __word_[_Np];
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static difference_type capacity() {
+ return static_cast<difference_type>(_Np * __bits_per_word);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit __bit_array(difference_type __s) : __size_(__s) {
+ if (__libcpp_is_constant_evaluated()) {
+ for (size_t __i = 0; __i != __bit_array<_Cp>::_Np; ++__i)
+ std::__construct_at(__word_ + __i, 0);
+ }
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator begin() {
+ return iterator(pointer_traits<__storage_pointer>::pointer_to(__word_[0]), 0);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator end() {
+ return iterator(pointer_traits<__storage_pointer>::pointer_to(__word_[0]) + __size_ / __bits_per_word,
+ static_cast<unsigned>(__size_ % __bits_per_word));
+ }
+};
+
+template <class _Cp>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false>
+rotate(__bit_iterator<_Cp, false> __first, __bit_iterator<_Cp, false> __middle, __bit_iterator<_Cp, false> __last) {
+ using _I1 = __bit_iterator<_Cp, false>;
+ using difference_type = typename _I1::difference_type;
+
+ difference_type __d1 = __middle - __first;
+ difference_type __d2 = __last - __middle;
+ _I1 __r = __first + __d2;
+ while (__d1 != 0 && __d2 != 0) {
+ if (__d1 <= __d2) {
+ if (__d1 <= __bit_array<_Cp>::capacity()) {
+ __bit_array<_Cp> __b(__d1);
+ std::copy(__first, __middle, __b.begin());
+ std::copy(__b.begin(), __b.end(), std::copy(__middle, __last, __first));
+ break;
+ } else {
+ __bit_iterator<_Cp, false> __mp = std::swap_ranges(__first, __middle, __middle);
+ __first = __middle;
+ __middle = __mp;
+ __d2 -= __d1;
+ }
+ } else {
+ if (__d2 <= __bit_array<_Cp>::capacity()) {
+ __bit_array<_Cp> __b(__d2);
+ std::copy(__middle, __last, __b.begin());
+ std::copy_backward(__b.begin(), __b.end(), std::copy_backward(__first, __middle, __last));
+ break;
+ } else {
+ __bit_iterator<_Cp, false> __mp = __first + __d2;
+ std::swap_ranges(__first, __mp, __middle);
+ __first = __mp;
+ __d1 -= __d2;
+ }
+ }
+ }
+ return __r;
+}
+
+// equal
+
+template <class _Cp, bool _IC1, bool _IC2>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __equal_unaligned(
+ __bit_iterator<_Cp, _IC1> __first1, __bit_iterator<_Cp, _IC1> __last1, __bit_iterator<_Cp, _IC2> __first2) {
+ using _It = __bit_iterator<_Cp, _IC1>;
+ using difference_type = typename _It::difference_type;
+ using __storage_type = typename _It::__storage_type;
+
+ const int __bits_per_word = _It::__bits_per_word;
+ difference_type __n = __last1 - __first1;
+ if (__n > 0) {
+ // do first word
+ if (__first1.__ctz_ != 0) {
+ unsigned __clz_f = __bits_per_word - __first1.__ctz_;
+ difference_type __dn = std::min(static_cast<difference_type>(__clz_f), __n);
+ __n -= __dn;
+ __storage_type __m = (~__storage_type(0) << __first1.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
+ __storage_type __b = *__first1.__seg_ & __m;
+ unsigned __clz_r = __bits_per_word - __first2.__ctz_;
+ __storage_type __ddn = std::min<__storage_type>(__dn, __clz_r);
+ __m = (~__storage_type(0) << __first2.__ctz_) & (~__storage_type(0) >> (__clz_r - __ddn));
+ if (__first2.__ctz_ > __first1.__ctz_) {
+ if ((*__first2.__seg_ & __m) != (__b << (__first2.__ctz_ - __first1.__ctz_)))
+ return false;
+ } else {
+ if ((*__first2.__seg_ & __m) != (__b >> (__first1.__ctz_ - __first2.__ctz_)))
+ return false;
+ }
+ __first2.__seg_ += (__ddn + __first2.__ctz_) / __bits_per_word;
+ __first2.__ctz_ = static_cast<unsigned>((__ddn + __first2.__ctz_) % __bits_per_word);
+ __dn -= __ddn;
+ if (__dn > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __dn);
+ if ((*__first2.__seg_ & __m) != (__b >> (__first1.__ctz_ + __ddn)))
+ return false;
+ __first2.__ctz_ = static_cast<unsigned>(__dn);
+ }
+ ++__first1.__seg_;
+ // __first1.__ctz_ = 0;
+ }
+ // __first1.__ctz_ == 0;
+ // do middle words
+ unsigned __clz_r = __bits_per_word - __first2.__ctz_;
+ __storage_type __m = ~__storage_type(0) << __first2.__ctz_;
+ for (; __n >= __bits_per_word; __n -= __bits_per_word, ++__first1.__seg_) {
+ __storage_type __b = *__first1.__seg_;
+ if ((*__first2.__seg_ & __m) != (__b << __first2.__ctz_))
+ return false;
+ ++__first2.__seg_;
+ if ((*__first2.__seg_ & ~__m) != (__b >> __clz_r))
+ return false;
+ }
+ // do last word
+ if (__n > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __storage_type __b = *__first1.__seg_ & __m;
+ __storage_type __dn = std::min(__n, static_cast<difference_type>(__clz_r));
+ __m = (~__storage_type(0) << __first2.__ctz_) & (~__storage_type(0) >> (__clz_r - __dn));
+ if ((*__first2.__seg_ & __m) != (__b << __first2.__ctz_))
+ return false;
+ __first2.__seg_ += (__dn + __first2.__ctz_) / __bits_per_word;
+ __first2.__ctz_ = static_cast<unsigned>((__dn + __first2.__ctz_) % __bits_per_word);
+ __n -= __dn;
+ if (__n > 0) {
+ __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ if ((*__first2.__seg_ & __m) != (__b >> __dn))
+ return false;
+ }
+ }
+ }
+ return true;
+}
+
+template <class _Cp, bool _IC1, bool _IC2>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __equal_aligned(
+ __bit_iterator<_Cp, _IC1> __first1, __bit_iterator<_Cp, _IC1> __last1, __bit_iterator<_Cp, _IC2> __first2) {
+ using _It = __bit_iterator<_Cp, _IC1>;
+ using difference_type = typename _It::difference_type;
+ using __storage_type = typename _It::__storage_type;
+
+ const int __bits_per_word = _It::__bits_per_word;
+ difference_type __n = __last1 - __first1;
+ if (__n > 0) {
+ // do first word
+ if (__first1.__ctz_ != 0) {
+ unsigned __clz = __bits_per_word - __first1.__ctz_;
+ difference_type __dn = std::min(static_cast<difference_type>(__clz), __n);
+ __n -= __dn;
+ __storage_type __m = (~__storage_type(0) << __first1.__ctz_) & (~__storage_type(0) >> (__clz - __dn));
+ if ((*__first2.__seg_ & __m) != (*__first1.__seg_ & __m))
+ return false;
+ ++__first2.__seg_;
+ ++__first1.__seg_;
+ // __first1.__ctz_ = 0;
+ // __first2.__ctz_ = 0;
+ }
+ // __first1.__ctz_ == 0;
+ // __first2.__ctz_ == 0;
+ // do middle words
+ for (; __n >= __bits_per_word; __n -= __bits_per_word, ++__first1.__seg_, ++__first2.__seg_)
+ if (*__first2.__seg_ != *__first1.__seg_)
+ return false;
+ // do last word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ if ((*__first2.__seg_ & __m) != (*__first1.__seg_ & __m))
+ return false;
+ }
+ }
+ return true;
+}
+
+template <class _Cp, bool _IC1, bool _IC2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+equal(__bit_iterator<_Cp, _IC1> __first1, __bit_iterator<_Cp, _IC1> __last1, __bit_iterator<_Cp, _IC2> __first2) {
+ if (__first1.__ctz_ == __first2.__ctz_)
+ return std::__equal_aligned(__first1, __last1, __first2);
+ return std::__equal_unaligned(__first1, __last1, __first2);
+}
+
+template <class _Cp, bool _IsConst, typename _Cp::__storage_type>
+class __bit_iterator {
+public:
+ using difference_type = typename _Cp::difference_type;
+ using value_type = bool;
+ using pointer = __bit_iterator;
+#ifndef _LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL
+ using reference = __conditional_t<_IsConst, __bit_const_reference<_Cp>, __bit_reference<_Cp> >;
+#else
+ using reference = __conditional_t<_IsConst, bool, __bit_reference<_Cp> >;
+#endif
+ using iterator_category = random_access_iterator_tag;
+
+private:
+ using __storage_type = typename _Cp::__storage_type;
+ using __storage_pointer =
+ __conditional_t<_IsConst, typename _Cp::__const_storage_pointer, typename _Cp::__storage_pointer>;
+
+ static const unsigned __bits_per_word = _Cp::__bits_per_word;
+
+ __storage_pointer __seg_;
+ unsigned __ctz_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator() _NOEXCEPT
+#if _LIBCPP_STD_VER >= 14
+ : __seg_(nullptr),
+ __ctz_(0)
+#endif
+ {
+ }
+
+ // When _IsConst=false, this is the copy constructor.
+ // It is non-trivial. Making it trivial would break ABI.
+ // When _IsConst=true, this is a converting constructor;
+ // the copy and move constructors are implicitly generated
+ // and trivial.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator(const __bit_iterator<_Cp, false>& __it) _NOEXCEPT
+ : __seg_(__it.__seg_),
+ __ctz_(__it.__ctz_) {}
+
+ // When _IsConst=false, we have a user-provided copy constructor,
+ // so we must also provide a copy assignment operator because
+ // the implicit generation of a defaulted one is deprecated.
+ // When _IsConst=true, the assignment operators are
+ // implicitly generated and trivial.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator&
+ operator=(const _If<_IsConst, struct __private_nat, __bit_iterator>& __it) {
+ __seg_ = __it.__seg_;
+ __ctz_ = __it.__ctz_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference operator*() const _NOEXCEPT {
+ return __conditional_t<_IsConst, __bit_const_reference<_Cp>, __bit_reference<_Cp> >(
+ __seg_, __storage_type(1) << __ctz_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator& operator++() {
+ if (__ctz_ != __bits_per_word - 1)
+ ++__ctz_;
+ else {
+ __ctz_ = 0;
+ ++__seg_;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator operator++(int) {
+ __bit_iterator __tmp = *this;
+ ++(*this);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator& operator--() {
+ if (__ctz_ != 0)
+ --__ctz_;
+ else {
+ __ctz_ = __bits_per_word - 1;
+ --__seg_;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator operator--(int) {
+ __bit_iterator __tmp = *this;
+ --(*this);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator& operator+=(difference_type __n) {
+ if (__n >= 0)
+ __seg_ += (__n + __ctz_) / __bits_per_word;
+ else
+ __seg_ += static_cast<difference_type>(__n - __bits_per_word + __ctz_ + 1) /
+ static_cast<difference_type>(__bits_per_word);
+ __n &= (__bits_per_word - 1);
+ __ctz_ = static_cast<unsigned>((__n + __ctz_) % __bits_per_word);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator& operator-=(difference_type __n) {
+ return *this += -__n;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator operator+(difference_type __n) const {
+ __bit_iterator __t(*this);
+ __t += __n;
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator operator-(difference_type __n) const {
+ __bit_iterator __t(*this);
+ __t -= __n;
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator
+ operator+(difference_type __n, const __bit_iterator& __it) {
+ return __it + __n;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 friend difference_type
+ operator-(const __bit_iterator& __x, const __bit_iterator& __y) {
+ return (__x.__seg_ - __y.__seg_) * __bits_per_word + __x.__ctz_ - __y.__ctz_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference operator[](difference_type __n) const {
+ return *(*this + __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ operator==(const __bit_iterator& __x, const __bit_iterator& __y) {
+ return __x.__seg_ == __y.__seg_ && __x.__ctz_ == __y.__ctz_;
+ }
+
+#if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ operator!=(const __bit_iterator& __x, const __bit_iterator& __y) {
+ return !(__x == __y);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ operator<(const __bit_iterator& __x, const __bit_iterator& __y) {
+ return __x.__seg_ < __y.__seg_ || (__x.__seg_ == __y.__seg_ && __x.__ctz_ < __y.__ctz_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ operator>(const __bit_iterator& __x, const __bit_iterator& __y) {
+ return __y < __x;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ operator<=(const __bit_iterator& __x, const __bit_iterator& __y) {
+ return !(__y < __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ operator>=(const __bit_iterator& __x, const __bit_iterator& __y) {
+ return !(__x < __y);
+ }
+#else // _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI constexpr friend strong_ordering
+ operator<=>(const __bit_iterator& __x, const __bit_iterator& __y) {
+ if (__x.__seg_ < __y.__seg_)
+ return strong_ordering::less;
+
+ if (__x.__seg_ == __y.__seg_)
+ return __x.__ctz_ <=> __y.__ctz_;
+
+ return strong_ordering::greater;
+ }
+#endif // _LIBCPP_STD_VER <= 17
+
+private:
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit __bit_iterator(__storage_pointer __s, unsigned __ctz) _NOEXCEPT
+ : __seg_(__s),
+ __ctz_(__ctz) {}
+
+ friend typename _Cp::__self;
+
+ friend class __bit_reference<_Cp>;
+ friend class __bit_const_reference<_Cp>;
+ friend class __bit_iterator<_Cp, true>;
+ template <class _Dp>
+ friend struct __bit_array;
+
+ template <bool _FillVal, class _Dp>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend void
+ __fill_n_bool(__bit_iterator<_Dp, false> __first, typename _Dp::size_type __n);
+
+ template <class _Dp, bool _IC>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator<_Dp, false> __copy_aligned(
+ __bit_iterator<_Dp, _IC> __first, __bit_iterator<_Dp, _IC> __last, __bit_iterator<_Dp, false> __result);
+ template <class _Dp, bool _IC>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator<_Dp, false> __copy_unaligned(
+ __bit_iterator<_Dp, _IC> __first, __bit_iterator<_Dp, _IC> __last, __bit_iterator<_Dp, false> __result);
+ template <class _Dp, bool _IC>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator<_Dp, false>
+ copy(__bit_iterator<_Dp, _IC> __first, __bit_iterator<_Dp, _IC> __last, __bit_iterator<_Dp, false> __result);
+ template <class _Dp, bool _IC>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator<_Dp, false> __copy_backward_aligned(
+ __bit_iterator<_Dp, _IC> __first, __bit_iterator<_Dp, _IC> __last, __bit_iterator<_Dp, false> __result);
+ template <class _Dp, bool _IC>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator<_Dp, false> __copy_backward_unaligned(
+ __bit_iterator<_Dp, _IC> __first, __bit_iterator<_Dp, _IC> __last, __bit_iterator<_Dp, false> __result);
+ template <class _Dp, bool _IC>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator<_Dp, false>
+ copy_backward(__bit_iterator<_Dp, _IC> __first, __bit_iterator<_Dp, _IC> __last, __bit_iterator<_Dp, false> __result);
+ template <class _Cl, class _Cr>
+ friend __bit_iterator<_Cr, false>
+ __swap_ranges_aligned(__bit_iterator<_Cl, false>, __bit_iterator<_Cl, false>, __bit_iterator<_Cr, false>);
+ template <class _Cl, class _Cr>
+ friend __bit_iterator<_Cr, false>
+ __swap_ranges_unaligned(__bit_iterator<_Cl, false>, __bit_iterator<_Cl, false>, __bit_iterator<_Cr, false>);
+ template <class _Cl, class _Cr>
+ friend __bit_iterator<_Cr, false>
+ swap_ranges(__bit_iterator<_Cl, false>, __bit_iterator<_Cl, false>, __bit_iterator<_Cr, false>);
+ template <class _Dp>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator<_Dp, false>
+ rotate(__bit_iterator<_Dp, false>, __bit_iterator<_Dp, false>, __bit_iterator<_Dp, false>);
+ template <class _Dp, bool _IC1, bool _IC2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ __equal_aligned(__bit_iterator<_Dp, _IC1>, __bit_iterator<_Dp, _IC1>, __bit_iterator<_Dp, _IC2>);
+ template <class _Dp, bool _IC1, bool _IC2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ __equal_unaligned(__bit_iterator<_Dp, _IC1>, __bit_iterator<_Dp, _IC1>, __bit_iterator<_Dp, _IC2>);
+ template <class _Dp, bool _IC1, bool _IC2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend bool
+ equal(__bit_iterator<_Dp, _IC1>, __bit_iterator<_Dp, _IC1>, __bit_iterator<_Dp, _IC2>);
+ template <bool _ToFind, class _Dp, bool _IC>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 friend __bit_iterator<_Dp, _IC>
+ __find_bool(__bit_iterator<_Dp, _IC>, typename _Dp::size_type);
+ template <bool _ToCount, class _Dp, bool _IC>
+ friend typename __bit_iterator<_Dp, _IC>::difference_type _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 __count_bool(__bit_iterator<_Dp, _IC>, typename _Dp::size_type);
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___BIT_REFERENCE
diff --git a/libcxx/include/__cxx03/__charconv/chars_format.h b/libcxx/include/__cxx03/__charconv/chars_format.h
new file mode 100644
index 00000000000000..c76cebd5d1847d
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/chars_format.h
@@ -0,0 +1,61 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_CHARS_FORMAT_H
+#define _LIBCPP___CHARCONV_CHARS_FORMAT_H
+
+#include <__config>
+#include <__utility/to_underlying.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+enum class chars_format { scientific = 0x1, fixed = 0x2, hex = 0x4, general = fixed | scientific };
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format operator~(chars_format __x) {
+ return chars_format(~std::__to_underlying(__x));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format operator&(chars_format __x, chars_format __y) {
+ return chars_format(std::__to_underlying(__x) & std::__to_underlying(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format operator|(chars_format __x, chars_format __y) {
+ return chars_format(std::__to_underlying(__x) | std::__to_underlying(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format operator^(chars_format __x, chars_format __y) {
+ return chars_format(std::__to_underlying(__x) ^ std::__to_underlying(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format& operator&=(chars_format& __x, chars_format __y) {
+ __x = __x & __y;
+ return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format& operator|=(chars_format& __x, chars_format __y) {
+ __x = __x | __y;
+ return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format& operator^=(chars_format& __x, chars_format __y) {
+ __x = __x ^ __y;
+ return __x;
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_CHARS_FORMAT_H
diff --git a/libcxx/include/__cxx03/__charconv/from_chars_integral.h b/libcxx/include/__cxx03/__charconv/from_chars_integral.h
new file mode 100644
index 00000000000000..c1f033b37b913e
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/from_chars_integral.h
@@ -0,0 +1,240 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_FROM_CHARS_INTEGRAL_H
+#define _LIBCPP___CHARCONV_FROM_CHARS_INTEGRAL_H
+
+#include <__algorithm/copy_n.h>
+#include <__assert>
+#include <__charconv/from_chars_result.h>
+#include <__charconv/traits.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__system_error/errc.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_unsigned.h>
+#include <__type_traits/make_unsigned.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+from_chars_result from_chars(const char*, const char*, bool, int = 10) = delete;
+
+template <typename _It, typename _Tp, typename _Fn, typename... _Ts>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__sign_combinator(_It __first, _It __last, _Tp& __value, _Fn __f, _Ts... __args) {
+ using __tl = numeric_limits<_Tp>;
+ decltype(std::__to_unsigned_like(__value)) __x;
+
+ bool __neg = (__first != __last && *__first == '-');
+ auto __r = __f(__neg ? __first + 1 : __first, __last, __x, __args...);
+ switch (__r.ec) {
+ case errc::invalid_argument:
+ return {__first, __r.ec};
+ case errc::result_out_of_range:
+ return __r;
+ default:
+ break;
+ }
+
+ if (__neg) {
+ if (__x <= std::__complement(std::__to_unsigned_like(__tl::min()))) {
+ __x = std::__complement(__x);
+ std::copy_n(std::addressof(__x), 1, std::addressof(__value));
+ return __r;
+ }
+ } else {
+ if (__x <= std::__to_unsigned_like(__tl::max())) {
+ __value = __x;
+ return __r;
+ }
+ }
+
+ return {__r.ptr, errc::result_out_of_range};
+}
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool __in_pattern(_Tp __c) {
+ return '0' <= __c && __c <= '9';
+}
+
+struct _LIBCPP_HIDDEN __in_pattern_result {
+ bool __ok;
+ int __val;
+
+ explicit _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI operator bool() const { return __ok; }
+};
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __in_pattern_result __in_pattern(_Tp __c, int __base) {
+ if (__base <= 10)
+ return {'0' <= __c && __c < '0' + __base, __c - '0'};
+ else if (std::__in_pattern(__c))
+ return {true, __c - '0'};
+ else if ('a' <= __c && __c < 'a' + __base - 10)
+ return {true, __c - 'a' + 10};
+ else
+ return {'A' <= __c && __c < 'A' + __base - 10, __c - 'A' + 10};
+}
+
+template <typename _It, typename _Tp, typename _Fn, typename... _Ts>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__subject_seq_combinator(_It __first, _It __last, _Tp& __value, _Fn __f, _Ts... __args) {
+ auto __find_non_zero = [](_It __firstit, _It __lastit) {
+ for (; __firstit != __lastit; ++__firstit)
+ if (*__firstit != '0')
+ break;
+ return __firstit;
+ };
+
+ auto __p = __find_non_zero(__first, __last);
+ if (__p == __last || !std::__in_pattern(*__p, __args...)) {
+ if (__p == __first)
+ return {__first, errc::invalid_argument};
+ else {
+ __value = 0;
+ return {__p, {}};
+ }
+ }
+
+ auto __r = __f(__p, __last, __value, __args...);
+ if (__r.ec == errc::result_out_of_range) {
+ for (; __r.ptr != __last; ++__r.ptr) {
+ if (!std::__in_pattern(*__r.ptr, __args...))
+ break;
+ }
+ }
+
+ return __r;
+}
+
+template <typename _Tp, __enable_if_t<is_unsigned<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars_atoi(const char* __first, const char* __last, _Tp& __value) {
+ using __tx = __itoa::__traits<_Tp>;
+ using __output_type = typename __tx::type;
+
+ return std::__subject_seq_combinator(
+ __first, __last, __value, [](const char* __f, const char* __l, _Tp& __val) -> from_chars_result {
+ __output_type __a, __b;
+ auto __p = __tx::__read(__f, __l, __a, __b);
+ if (__p == __l || !std::__in_pattern(*__p)) {
+ __output_type __m = numeric_limits<_Tp>::max();
+ if (__m >= __a && __m - __a >= __b) {
+ __val = __a + __b;
+ return {__p, {}};
+ }
+ }
+ return {__p, errc::result_out_of_range};
+ });
+}
+
+template <typename _Tp, __enable_if_t<is_signed<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars_atoi(const char* __first, const char* __last, _Tp& __value) {
+ using __t = decltype(std::__to_unsigned_like(__value));
+ return std::__sign_combinator(__first, __last, __value, __from_chars_atoi<__t>);
+}
+
+/*
+// Code used to generate __from_chars_log2f_lut.
+#include <cmath>
+#include <format>
+#include <iostream>
+
+int main() {
+ for (int i = 2; i <= 36; ++i)
+ std::cout << std::format("{},\n", log2f(i));
+}
+*/
+/// log2f table for bases [2, 36].
+inline constexpr float __from_chars_log2f_lut[35] = {
+ 1, 1.5849625, 2, 2.321928, 2.5849626, 2.807355, 3, 3.169925, 3.321928,
+ 3.4594316, 3.5849626, 3.7004397, 3.807355, 3.9068906, 4, 4.087463, 4.169925, 4.2479277,
+ 4.321928, 4.3923173, 4.4594316, 4.523562, 4.5849624, 4.643856, 4.70044, 4.7548876, 4.807355,
+ 4.857981, 4.9068904, 4.9541965, 5, 5.044394, 5.087463, 5.129283, 5.169925};
+
+template <typename _Tp, __enable_if_t<is_unsigned<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars_integral(const char* __first, const char* __last, _Tp& __value, int __base) {
+ if (__base == 10)
+ return std::__from_chars_atoi(__first, __last, __value);
+
+ return std::__subject_seq_combinator(
+ __first,
+ __last,
+ __value,
+ [](const char* __p, const char* __lastp, _Tp& __val, int __b) -> from_chars_result {
+ using __tl = numeric_limits<_Tp>;
+ // __base is always between 2 and 36 inclusive.
+ auto __digits = __tl::digits / __from_chars_log2f_lut[__b - 2];
+ _Tp __x = __in_pattern(*__p++, __b).__val, __y = 0;
+
+ for (int __i = 1; __p != __lastp; ++__i, ++__p) {
+ if (auto __c = __in_pattern(*__p, __b)) {
+ if (__i < __digits - 1)
+ __x = __x * __b + __c.__val;
+ else {
+ if (!__itoa::__mul_overflowed(__x, __b, __x))
+ ++__p;
+ __y = __c.__val;
+ break;
+ }
+ } else
+ break;
+ }
+
+ if (__p == __lastp || !__in_pattern(*__p, __b)) {
+ if (__tl::max() - __x >= __y) {
+ __val = __x + __y;
+ return {__p, {}};
+ }
+ }
+ return {__p, errc::result_out_of_range};
+ },
+ __base);
+}
+
+template <typename _Tp, __enable_if_t<is_signed<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars_integral(const char* __first, const char* __last, _Tp& __value, int __base) {
+ using __t = decltype(std::__to_unsigned_like(__value));
+ return std::__sign_combinator(__first, __last, __value, __from_chars_integral<__t>, __base);
+}
+
+template <typename _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+from_chars(const char* __first, const char* __last, _Tp& __value) {
+ return std::__from_chars_atoi(__first, __last, __value);
+}
+
+template <typename _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+from_chars(const char* __first, const char* __last, _Tp& __value, int __base) {
+ _LIBCPP_ASSERT_UNCATEGORIZED(2 <= __base && __base <= 36, "base not in [2, 36]");
+ return std::__from_chars_integral(__first, __last, __value, __base);
+}
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_FROM_CHARS_INTEGRAL_H
diff --git a/libcxx/include/__cxx03/__charconv/from_chars_result.h b/libcxx/include/__cxx03/__charconv/from_chars_result.h
new file mode 100644
index 00000000000000..a7bfd6530a8a0e
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/from_chars_result.h
@@ -0,0 +1,39 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_FROM_CHARS_RESULT_H
+#define _LIBCPP___CHARCONV_FROM_CHARS_RESULT_H
+
+#include <__config>
+#include <__system_error/errc.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+struct _LIBCPP_EXPORTED_FROM_ABI from_chars_result {
+ const char* ptr;
+ errc ec;
+# if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const from_chars_result&, const from_chars_result&) = default;
+# endif
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return ec == errc{}; }
+# endif
+};
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_FROM_CHARS_RESULT_H
diff --git a/libcxx/include/__cxx03/__charconv/tables.h b/libcxx/include/__cxx03/__charconv/tables.h
new file mode 100644
index 00000000000000..6b93536b8c1bac
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/tables.h
@@ -0,0 +1,163 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_TABLES
+#define _LIBCPP___CHARCONV_TABLES
+
+#include <__config>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+namespace __itoa {
+
+inline constexpr char __base_2_lut[64] = {
+ '0', '0', '0', '0', '0', '0', '0', '1', '0', '0', '1', '0', '0', '0', '1', '1', '0', '1', '0', '0', '0', '1',
+ '0', '1', '0', '1', '1', '0', '0', '1', '1', '1', '1', '0', '0', '0', '1', '0', '0', '1', '1', '0', '1', '0',
+ '1', '0', '1', '1', '1', '1', '0', '0', '1', '1', '0', '1', '1', '1', '1', '0', '1', '1', '1', '1'};
+
+inline constexpr char __base_8_lut[128] = {
+ '0', '0', '0', '1', '0', '2', '0', '3', '0', '4', '0', '5', '0', '6', '0', '7', '1', '0', '1', '1', '1', '2',
+ '1', '3', '1', '4', '1', '5', '1', '6', '1', '7', '2', '0', '2', '1', '2', '2', '2', '3', '2', '4', '2', '5',
+ '2', '6', '2', '7', '3', '0', '3', '1', '3', '2', '3', '3', '3', '4', '3', '5', '3', '6', '3', '7', '4', '0',
+ '4', '1', '4', '2', '4', '3', '4', '4', '4', '5', '4', '6', '4', '7', '5', '0', '5', '1', '5', '2', '5', '3',
+ '5', '4', '5', '5', '5', '6', '5', '7', '6', '0', '6', '1', '6', '2', '6', '3', '6', '4', '6', '5', '6', '6',
+ '6', '7', '7', '0', '7', '1', '7', '2', '7', '3', '7', '4', '7', '5', '7', '6', '7', '7'};
+
+inline constexpr char __base_16_lut[512] = {
+ '0', '0', '0', '1', '0', '2', '0', '3', '0', '4', '0', '5', '0', '6', '0', '7', '0', '8', '0', '9', '0', 'a', '0',
+ 'b', '0', 'c', '0', 'd', '0', 'e', '0', 'f', '1', '0', '1', '1', '1', '2', '1', '3', '1', '4', '1', '5', '1', '6',
+ '1', '7', '1', '8', '1', '9', '1', 'a', '1', 'b', '1', 'c', '1', 'd', '1', 'e', '1', 'f', '2', '0', '2', '1', '2',
+ '2', '2', '3', '2', '4', '2', '5', '2', '6', '2', '7', '2', '8', '2', '9', '2', 'a', '2', 'b', '2', 'c', '2', 'd',
+ '2', 'e', '2', 'f', '3', '0', '3', '1', '3', '2', '3', '3', '3', '4', '3', '5', '3', '6', '3', '7', '3', '8', '3',
+ '9', '3', 'a', '3', 'b', '3', 'c', '3', 'd', '3', 'e', '3', 'f', '4', '0', '4', '1', '4', '2', '4', '3', '4', '4',
+ '4', '5', '4', '6', '4', '7', '4', '8', '4', '9', '4', 'a', '4', 'b', '4', 'c', '4', 'd', '4', 'e', '4', 'f', '5',
+ '0', '5', '1', '5', '2', '5', '3', '5', '4', '5', '5', '5', '6', '5', '7', '5', '8', '5', '9', '5', 'a', '5', 'b',
+ '5', 'c', '5', 'd', '5', 'e', '5', 'f', '6', '0', '6', '1', '6', '2', '6', '3', '6', '4', '6', '5', '6', '6', '6',
+ '7', '6', '8', '6', '9', '6', 'a', '6', 'b', '6', 'c', '6', 'd', '6', 'e', '6', 'f', '7', '0', '7', '1', '7', '2',
+ '7', '3', '7', '4', '7', '5', '7', '6', '7', '7', '7', '8', '7', '9', '7', 'a', '7', 'b', '7', 'c', '7', 'd', '7',
+ 'e', '7', 'f', '8', '0', '8', '1', '8', '2', '8', '3', '8', '4', '8', '5', '8', '6', '8', '7', '8', '8', '8', '9',
+ '8', 'a', '8', 'b', '8', 'c', '8', 'd', '8', 'e', '8', 'f', '9', '0', '9', '1', '9', '2', '9', '3', '9', '4', '9',
+ '5', '9', '6', '9', '7', '9', '8', '9', '9', '9', 'a', '9', 'b', '9', 'c', '9', 'd', '9', 'e', '9', 'f', 'a', '0',
+ 'a', '1', 'a', '2', 'a', '3', 'a', '4', 'a', '5', 'a', '6', 'a', '7', 'a', '8', 'a', '9', 'a', 'a', 'a', 'b', 'a',
+ 'c', 'a', 'd', 'a', 'e', 'a', 'f', 'b', '0', 'b', '1', 'b', '2', 'b', '3', 'b', '4', 'b', '5', 'b', '6', 'b', '7',
+ 'b', '8', 'b', '9', 'b', 'a', 'b', 'b', 'b', 'c', 'b', 'd', 'b', 'e', 'b', 'f', 'c', '0', 'c', '1', 'c', '2', 'c',
+ '3', 'c', '4', 'c', '5', 'c', '6', 'c', '7', 'c', '8', 'c', '9', 'c', 'a', 'c', 'b', 'c', 'c', 'c', 'd', 'c', 'e',
+ 'c', 'f', 'd', '0', 'd', '1', 'd', '2', 'd', '3', 'd', '4', 'd', '5', 'd', '6', 'd', '7', 'd', '8', 'd', '9', 'd',
+ 'a', 'd', 'b', 'd', 'c', 'd', 'd', 'd', 'e', 'd', 'f', 'e', '0', 'e', '1', 'e', '2', 'e', '3', 'e', '4', 'e', '5',
+ 'e', '6', 'e', '7', 'e', '8', 'e', '9', 'e', 'a', 'e', 'b', 'e', 'c', 'e', 'd', 'e', 'e', 'e', 'f', 'f', '0', 'f',
+ '1', 'f', '2', 'f', '3', 'f', '4', 'f', '5', 'f', '6', 'f', '7', 'f', '8', 'f', '9', 'f', 'a', 'f', 'b', 'f', 'c',
+ 'f', 'd', 'f', 'e', 'f', 'f'};
+
+inline constexpr uint32_t __pow10_32[10] = {
+ UINT32_C(0),
+ UINT32_C(10),
+ UINT32_C(100),
+ UINT32_C(1000),
+ UINT32_C(10000),
+ UINT32_C(100000),
+ UINT32_C(1000000),
+ UINT32_C(10000000),
+ UINT32_C(100000000),
+ UINT32_C(1000000000)};
+
+inline constexpr uint64_t __pow10_64[20] = {
+ UINT64_C(0),
+ UINT64_C(10),
+ UINT64_C(100),
+ UINT64_C(1000),
+ UINT64_C(10000),
+ UINT64_C(100000),
+ UINT64_C(1000000),
+ UINT64_C(10000000),
+ UINT64_C(100000000),
+ UINT64_C(1000000000),
+ UINT64_C(10000000000),
+ UINT64_C(100000000000),
+ UINT64_C(1000000000000),
+ UINT64_C(10000000000000),
+ UINT64_C(100000000000000),
+ UINT64_C(1000000000000000),
+ UINT64_C(10000000000000000),
+ UINT64_C(100000000000000000),
+ UINT64_C(1000000000000000000),
+ UINT64_C(10000000000000000000)};
+
+# ifndef _LIBCPP_HAS_NO_INT128
+inline constexpr int __pow10_128_offset = 0;
+inline constexpr __uint128_t __pow10_128[40] = {
+ UINT64_C(0),
+ UINT64_C(10),
+ UINT64_C(100),
+ UINT64_C(1000),
+ UINT64_C(10000),
+ UINT64_C(100000),
+ UINT64_C(1000000),
+ UINT64_C(10000000),
+ UINT64_C(100000000),
+ UINT64_C(1000000000),
+ UINT64_C(10000000000),
+ UINT64_C(100000000000),
+ UINT64_C(1000000000000),
+ UINT64_C(10000000000000),
+ UINT64_C(100000000000000),
+ UINT64_C(1000000000000000),
+ UINT64_C(10000000000000000),
+ UINT64_C(100000000000000000),
+ UINT64_C(1000000000000000000),
+ UINT64_C(10000000000000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000000000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000000000000000),
+ __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000000000000),
+ (__uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000000000000)) * 10};
+# endif
+
+inline constexpr char __digits_base_10[200] = {
+ // clang-format off
+ '0', '0', '0', '1', '0', '2', '0', '3', '0', '4', '0', '5', '0', '6', '0', '7', '0', '8', '0', '9',
+ '1', '0', '1', '1', '1', '2', '1', '3', '1', '4', '1', '5', '1', '6', '1', '7', '1', '8', '1', '9',
+ '2', '0', '2', '1', '2', '2', '2', '3', '2', '4', '2', '5', '2', '6', '2', '7', '2', '8', '2', '9',
+ '3', '0', '3', '1', '3', '2', '3', '3', '3', '4', '3', '5', '3', '6', '3', '7', '3', '8', '3', '9',
+ '4', '0', '4', '1', '4', '2', '4', '3', '4', '4', '4', '5', '4', '6', '4', '7', '4', '8', '4', '9',
+ '5', '0', '5', '1', '5', '2', '5', '3', '5', '4', '5', '5', '5', '6', '5', '7', '5', '8', '5', '9',
+ '6', '0', '6', '1', '6', '2', '6', '3', '6', '4', '6', '5', '6', '6', '6', '7', '6', '8', '6', '9',
+ '7', '0', '7', '1', '7', '2', '7', '3', '7', '4', '7', '5', '7', '6', '7', '7', '7', '8', '7', '9',
+ '8', '0', '8', '1', '8', '2', '8', '3', '8', '4', '8', '5', '8', '6', '8', '7', '8', '8', '8', '9',
+ '9', '0', '9', '1', '9', '2', '9', '3', '9', '4', '9', '5', '9', '6', '9', '7', '9', '8', '9', '9'};
+// clang-format on
+
+} // namespace __itoa
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_TABLES
diff --git a/libcxx/include/__cxx03/__charconv/to_chars.h b/libcxx/include/__cxx03/__charconv/to_chars.h
new file mode 100644
index 00000000000000..8ef09af737559f
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/to_chars.h
@@ -0,0 +1,25 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_TO_CHARS
+#define _LIBCPP___CHARCONV_TO_CHARS
+
+#include <__charconv/to_chars_floating_point.h>
+#include <__charconv/to_chars_integral.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS
diff --git a/libcxx/include/__cxx03/__charconv/to_chars_base_10.h b/libcxx/include/__cxx03/__charconv/to_chars_base_10.h
new file mode 100644
index 00000000000000..c49f4f6797aa43
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/to_chars_base_10.h
@@ -0,0 +1,188 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_TO_CHARS_BASE_10_H
+#define _LIBCPP___CHARCONV_TO_CHARS_BASE_10_H
+
+#include <__algorithm/copy_n.h>
+#include <__assert>
+#include <__charconv/tables.h>
+#include <__config>
+#include <cstdint>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+namespace __itoa {
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append1(char* __first, uint32_t __value) noexcept {
+ *__first = '0' + static_cast<char>(__value);
+ return __first + 1;
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append2(char* __first, uint32_t __value) noexcept {
+ return std::copy_n(&__digits_base_10[__value * 2], 2, __first);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append3(char* __first, uint32_t __value) noexcept {
+ return __itoa::__append2(__itoa::__append1(__first, __value / 100), __value % 100);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append4(char* __first, uint32_t __value) noexcept {
+ return __itoa::__append2(__itoa::__append2(__first, __value / 100), __value % 100);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append5(char* __first, uint32_t __value) noexcept {
+ return __itoa::__append4(__itoa::__append1(__first, __value / 10000), __value % 10000);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append6(char* __first, uint32_t __value) noexcept {
+ return __itoa::__append4(__itoa::__append2(__first, __value / 10000), __value % 10000);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append7(char* __first, uint32_t __value) noexcept {
+ return __itoa::__append6(__itoa::__append1(__first, __value / 1000000), __value % 1000000);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append8(char* __first, uint32_t __value) noexcept {
+ return __itoa::__append6(__itoa::__append2(__first, __value / 1000000), __value % 1000000);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append9(char* __first, uint32_t __value) noexcept {
+ return __itoa::__append8(__itoa::__append1(__first, __value / 100000000), __value % 100000000);
+}
+
+template <class _Tp>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char* __append10(char* __first, _Tp __value) noexcept {
+ return __itoa::__append8(__itoa::__append2(__first, static_cast<uint32_t>(__value / 100000000)),
+ static_cast<uint32_t>(__value % 100000000));
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char*
+__base_10_u32(char* __first, uint32_t __value) noexcept {
+ if (__value < 1000000) {
+ if (__value < 10000) {
+ if (__value < 100) {
+ // 0 <= __value < 100
+ if (__value < 10)
+ return __itoa::__append1(__first, __value);
+ return __itoa::__append2(__first, __value);
+ }
+ // 100 <= __value < 10'000
+ if (__value < 1000)
+ return __itoa::__append3(__first, __value);
+ return __itoa::__append4(__first, __value);
+ }
+
+ // 10'000 <= __value < 1'000'000
+ if (__value < 100000)
+ return __itoa::__append5(__first, __value);
+ return __itoa::__append6(__first, __value);
+ }
+
+ // __value => 1'000'000
+ if (__value < 100000000) {
+ // 1'000'000 <= __value < 100'000'000
+ if (__value < 10000000)
+ return __itoa::__append7(__first, __value);
+ return __itoa::__append8(__first, __value);
+ }
+
+ // 100'000'000 <= __value < max
+ if (__value < 1000000000)
+ return __itoa::__append9(__first, __value);
+ return __itoa::__append10(__first, __value);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char*
+__base_10_u64(char* __buffer, uint64_t __value) noexcept {
+ if (__value <= UINT32_MAX)
+ return __itoa::__base_10_u32(__buffer, static_cast<uint32_t>(__value));
+
+ // Numbers in the range UINT32_MAX <= val < 10'000'000'000 always contain 10
+ // digits and are outputted after this if statement.
+ if (__value >= 10000000000) {
+ // This function properly deterimines the first non-zero leading digit.
+ __buffer = __itoa::__base_10_u32(__buffer, static_cast<uint32_t>(__value / 10000000000));
+ __value %= 10000000000;
+ }
+ return __itoa::__append10(__buffer, __value);
+}
+
+# ifndef _LIBCPP_HAS_NO_INT128
+/// \returns 10^\a exp
+///
+/// \pre \a exp [19, 39]
+///
+/// \note The lookup table contains a partial set of exponents limiting the
+/// range that can be used. However the range is sufficient for
+/// \ref __base_10_u128.
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline __uint128_t __pow_10(int __exp) noexcept {
+ _LIBCPP_ASSERT_INTERNAL(__exp >= __pow10_128_offset, "Index out of bounds");
+ return __pow10_128[__exp - __pow10_128_offset];
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char*
+__base_10_u128(char* __buffer, __uint128_t __value) noexcept {
+ _LIBCPP_ASSERT_INTERNAL(
+ __value > numeric_limits<uint64_t>::max(), "The optimizations for this algorithm fails when this isn't true.");
+
+ // Unlike the 64 to 32 bit case the 128 bit case the "upper half" can't be
+ // stored in the "lower half". Instead we first need to handle the top most
+ // digits separately.
+ //
+ // Maximum unsigned values
+ // 64 bit 18'446'744'073'709'551'615 (20 digits)
+ // 128 bit 340'282'366'920'938'463'463'374'607'431'768'211'455 (39 digits)
+ // step 1 ^ ([0-1] digits)
+ // step 2 ^^^^^^^^^^^^^^^^^^^^^^^^^ ([0-19] digits)
+ // step 3 ^^^^^^^^^^^^^^^^^^^^^^^^^ (19 digits)
+ if (__value >= __itoa::__pow_10(38)) {
+ // step 1
+ __buffer = __itoa::__append1(__buffer, static_cast<uint32_t>(__value / __itoa::__pow_10(38)));
+ __value %= __itoa::__pow_10(38);
+
+ // step 2 always 19 digits.
+ // They are handled here since leading zeros need to be appended to the buffer,
+ __buffer = __itoa::__append9(__buffer, static_cast<uint32_t>(__value / __itoa::__pow_10(29)));
+ __value %= __itoa::__pow_10(29);
+ __buffer = __itoa::__append10(__buffer, static_cast<uint64_t>(__value / __itoa::__pow_10(19)));
+ __value %= __itoa::__pow_10(19);
+ } else {
+ // step 2
+ // This version needs to determine the position of the leading non-zero digit.
+ __buffer = __base_10_u64(__buffer, static_cast<uint64_t>(__value / __itoa::__pow_10(19)));
+ __value %= __itoa::__pow_10(19);
+ }
+
+ // Step 3
+ __buffer = __itoa::__append9(__buffer, static_cast<uint32_t>(__value / 10000000000));
+ __buffer = __itoa::__append10(__buffer, static_cast<uint64_t>(__value % 10000000000));
+
+ return __buffer;
+}
+# endif
+} // namespace __itoa
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS_BASE_10_H
diff --git a/libcxx/include/__cxx03/__charconv/to_chars_floating_point.h b/libcxx/include/__cxx03/__charconv/to_chars_floating_point.h
new file mode 100644
index 00000000000000..118f316b21a102
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/to_chars_floating_point.h
@@ -0,0 +1,55 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_TO_CHARS_FLOATING_POINT_H
+#define _LIBCPP___CHARCONV_TO_CHARS_FLOATING_POINT_H
+
+#include <__charconv/chars_format.h>
+#include <__charconv/to_chars_result.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, float __value);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, double __value);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, long double __value);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, float __value, chars_format __fmt);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, double __value, chars_format __fmt);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, long double __value, chars_format __fmt);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, float __value, chars_format __fmt, int __precision);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, double __value, chars_format __fmt, int __precision);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, long double __value, chars_format __fmt, int __precision);
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS_FLOATING_POINT_H
diff --git a/libcxx/include/__cxx03/__charconv/to_chars_integral.h b/libcxx/include/__cxx03/__charconv/to_chars_integral.h
new file mode 100644
index 00000000000000..0369f4dfb9bda6
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/to_chars_integral.h
@@ -0,0 +1,327 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_TO_CHARS_INTEGRAL_H
+#define _LIBCPP___CHARCONV_TO_CHARS_INTEGRAL_H
+
+#include <__algorithm/copy_n.h>
+#include <__assert>
+#include <__bit/countl.h>
+#include <__charconv/tables.h>
+#include <__charconv/to_chars_base_10.h>
+#include <__charconv/to_chars_result.h>
+#include <__charconv/traits.h>
+#include <__config>
+#include <__system_error/errc.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/make_32_64_or_128_bit.h>
+#include <__type_traits/make_unsigned.h>
+#include <__utility/unreachable.h>
+#include <cstddef>
+#include <cstdint>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+to_chars_result to_chars(char*, char*, bool, int = 10) = delete;
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_itoa(char* __first, char* __last, _Tp __value, false_type);
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_itoa(char* __first, char* __last, _Tp __value, true_type) {
+ auto __x = std::__to_unsigned_like(__value);
+ if (__value < 0 && __first != __last) {
+ *__first++ = '-';
+ __x = std::__complement(__x);
+ }
+
+ return std::__to_chars_itoa(__first, __last, __x, false_type());
+}
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_itoa(char* __first, char* __last, _Tp __value, false_type) {
+ using __tx = __itoa::__traits<_Tp>;
+ auto __diff = __last - __first;
+
+ if (__tx::digits <= __diff || __tx::__width(__value) <= __diff)
+ return {__tx::__convert(__first, __value), errc(0)};
+ else
+ return {__last, errc::value_too_large};
+}
+
+# ifndef _LIBCPP_HAS_NO_INT128
+template <>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_itoa(char* __first, char* __last, __uint128_t __value, false_type) {
+ // When the value fits in 64-bits use the 64-bit code path. This reduces
+ // the number of expensive calculations on 128-bit values.
+ //
+ // NOTE the 128-bit code path requires this optimization.
+ if (__value <= numeric_limits<uint64_t>::max())
+ return __to_chars_itoa(__first, __last, static_cast<uint64_t>(__value), false_type());
+
+ using __tx = __itoa::__traits<__uint128_t>;
+ auto __diff = __last - __first;
+
+ if (__tx::digits <= __diff || __tx::__width(__value) <= __diff)
+ return {__tx::__convert(__first, __value), errc(0)};
+ else
+ return {__last, errc::value_too_large};
+}
+# endif
+
+template <class _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value, int __base, false_type);
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value, int __base, true_type) {
+ auto __x = std::__to_unsigned_like(__value);
+ if (__value < 0 && __first != __last) {
+ *__first++ = '-';
+ __x = std::__complement(__x);
+ }
+
+ return std::__to_chars_integral(__first, __last, __x, __base, false_type());
+}
+
+namespace __itoa {
+
+template <unsigned _Base>
+struct _LIBCPP_HIDDEN __integral;
+
+template <>
+struct _LIBCPP_HIDDEN __integral<2> {
+ template <typename _Tp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr int __width(_Tp __value) noexcept {
+ // If value == 0 still need one digit. If the value != this has no
+ // effect since the code scans for the most significant bit set. (Note
+ // that __libcpp_clz doesn't work for 0.)
+ return numeric_limits<_Tp>::digits - std::__libcpp_clz(__value | 1);
+ }
+
+ template <typename _Tp>
+ _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI static to_chars_result
+ __to_chars(char* __first, char* __last, _Tp __value) {
+ ptrdiff_t __cap = __last - __first;
+ int __n = __width(__value);
+ if (__n > __cap)
+ return {__last, errc::value_too_large};
+
+ __last = __first + __n;
+ char* __p = __last;
+ const unsigned __divisor = 16;
+ while (__value > __divisor) {
+ unsigned __c = __value % __divisor;
+ __value /= __divisor;
+ __p -= 4;
+ std::copy_n(&__base_2_lut[4 * __c], 4, __p);
+ }
+ do {
+ unsigned __c = __value % 2;
+ __value /= 2;
+ *--__p = "01"[__c];
+ } while (__value != 0);
+ return {__last, errc(0)};
+ }
+};
+
+template <>
+struct _LIBCPP_HIDDEN __integral<8> {
+ template <typename _Tp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr int __width(_Tp __value) noexcept {
+ // If value == 0 still need one digit. If the value != this has no
+ // effect since the code scans for the most significat bit set. (Note
+ // that __libcpp_clz doesn't work for 0.)
+ return ((numeric_limits<_Tp>::digits - std::__libcpp_clz(__value | 1)) + 2) / 3;
+ }
+
+ template <typename _Tp>
+ _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI static to_chars_result
+ __to_chars(char* __first, char* __last, _Tp __value) {
+ ptrdiff_t __cap = __last - __first;
+ int __n = __width(__value);
+ if (__n > __cap)
+ return {__last, errc::value_too_large};
+
+ __last = __first + __n;
+ char* __p = __last;
+ unsigned __divisor = 64;
+ while (__value > __divisor) {
+ unsigned __c = __value % __divisor;
+ __value /= __divisor;
+ __p -= 2;
+ std::copy_n(&__base_8_lut[2 * __c], 2, __p);
+ }
+ do {
+ unsigned __c = __value % 8;
+ __value /= 8;
+ *--__p = "01234567"[__c];
+ } while (__value != 0);
+ return {__last, errc(0)};
+ }
+};
+
+template <>
+struct _LIBCPP_HIDDEN __integral<16> {
+ template <typename _Tp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr int __width(_Tp __value) noexcept {
+ // If value == 0 still need one digit. If the value != this has no
+ // effect since the code scans for the most significat bit set. (Note
+ // that __libcpp_clz doesn't work for 0.)
+ return (numeric_limits<_Tp>::digits - std::__libcpp_clz(__value | 1) + 3) / 4;
+ }
+
+ template <typename _Tp>
+ _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI static to_chars_result
+ __to_chars(char* __first, char* __last, _Tp __value) {
+ ptrdiff_t __cap = __last - __first;
+ int __n = __width(__value);
+ if (__n > __cap)
+ return {__last, errc::value_too_large};
+
+ __last = __first + __n;
+ char* __p = __last;
+ unsigned __divisor = 256;
+ while (__value > __divisor) {
+ unsigned __c = __value % __divisor;
+ __value /= __divisor;
+ __p -= 2;
+ std::copy_n(&__base_16_lut[2 * __c], 2, __p);
+ }
+ if (__first != __last)
+ do {
+ unsigned __c = __value % 16;
+ __value /= 16;
+ *--__p = "0123456789abcdef"[__c];
+ } while (__value != 0);
+ return {__last, errc(0)};
+ }
+};
+
+} // namespace __itoa
+
+template <unsigned _Base, typename _Tp, __enable_if_t<(sizeof(_Tp) >= sizeof(unsigned)), int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __to_chars_integral_width(_Tp __value) {
+ return __itoa::__integral<_Base>::__width(__value);
+}
+
+template <unsigned _Base, typename _Tp, __enable_if_t<(sizeof(_Tp) < sizeof(unsigned)), int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __to_chars_integral_width(_Tp __value) {
+ return std::__to_chars_integral_width<_Base>(static_cast<unsigned>(__value));
+}
+
+template <unsigned _Base, typename _Tp, __enable_if_t<(sizeof(_Tp) >= sizeof(unsigned)), int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value) {
+ return __itoa::__integral<_Base>::__to_chars(__first, __last, __value);
+}
+
+template <unsigned _Base, typename _Tp, __enable_if_t<(sizeof(_Tp) < sizeof(unsigned)), int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value) {
+ return std::__to_chars_integral<_Base>(__first, __last, static_cast<unsigned>(__value));
+}
+
+template <typename _Tp>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __to_chars_integral_width(_Tp __value, unsigned __base) {
+ _LIBCPP_ASSERT_INTERNAL(__value >= 0, "The function requires a non-negative value.");
+
+ unsigned __base_2 = __base * __base;
+ unsigned __base_3 = __base_2 * __base;
+ unsigned __base_4 = __base_2 * __base_2;
+
+ int __r = 0;
+ while (true) {
+ if (__value < __base)
+ return __r + 1;
+ if (__value < __base_2)
+ return __r + 2;
+ if (__value < __base_3)
+ return __r + 3;
+ if (__value < __base_4)
+ return __r + 4;
+
+ __value /= __base_4;
+ __r += 4;
+ }
+
+ __libcpp_unreachable();
+}
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value, int __base, false_type) {
+ if (__base == 10) [[likely]]
+ return std::__to_chars_itoa(__first, __last, __value, false_type());
+
+ switch (__base) {
+ case 2:
+ return std::__to_chars_integral<2>(__first, __last, __value);
+ case 8:
+ return std::__to_chars_integral<8>(__first, __last, __value);
+ case 16:
+ return std::__to_chars_integral<16>(__first, __last, __value);
+ }
+
+ ptrdiff_t __cap = __last - __first;
+ int __n = std::__to_chars_integral_width(__value, __base);
+ if (__n > __cap)
+ return {__last, errc::value_too_large};
+
+ __last = __first + __n;
+ char* __p = __last;
+ do {
+ unsigned __c = __value % __base;
+ __value /= __base;
+ *--__p = "0123456789abcdefghijklmnopqrstuvwxyz"[__c];
+ } while (__value != 0);
+ return {__last, errc(0)};
+}
+
+template <typename _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, _Tp __value) {
+ using _Type = __make_32_64_or_128_bit_t<_Tp>;
+ static_assert(!is_same<_Type, void>::value, "unsupported integral type used in to_chars");
+ return std::__to_chars_itoa(__first, __last, static_cast<_Type>(__value), is_signed<_Tp>());
+}
+
+template <typename _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, _Tp __value, int __base) {
+ _LIBCPP_ASSERT_UNCATEGORIZED(2 <= __base && __base <= 36, "base not in [2, 36]");
+
+ using _Type = __make_32_64_or_128_bit_t<_Tp>;
+ return std::__to_chars_integral(__first, __last, static_cast<_Type>(__value), __base, is_signed<_Tp>());
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS_INTEGRAL_H
diff --git a/libcxx/include/__cxx03/__charconv/to_chars_result.h b/libcxx/include/__cxx03/__charconv/to_chars_result.h
new file mode 100644
index 00000000000000..8df0897a49fbbd
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/to_chars_result.h
@@ -0,0 +1,39 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_TO_CHARS_RESULT_H
+#define _LIBCPP___CHARCONV_TO_CHARS_RESULT_H
+
+#include <__config>
+#include <__system_error/errc.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+struct _LIBCPP_EXPORTED_FROM_ABI to_chars_result {
+ char* ptr;
+ errc ec;
+# if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const to_chars_result&, const to_chars_result&) = default;
+# endif
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return ec == errc{}; }
+# endif
+};
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS_RESULT_H
diff --git a/libcxx/include/__cxx03/__charconv/traits.h b/libcxx/include/__cxx03/__charconv/traits.h
new file mode 100644
index 00000000000000..c91c6da3247978
--- /dev/null
+++ b/libcxx/include/__cxx03/__charconv/traits.h
@@ -0,0 +1,200 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHARCONV_TRAITS
+#define _LIBCPP___CHARCONV_TRAITS
+
+#include <__assert>
+#include <__bit/countl.h>
+#include <__charconv/tables.h>
+#include <__charconv/to_chars_base_10.h>
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_unsigned.h>
+#include <cstdint>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+namespace __itoa {
+
+template <typename _Tp, typename = void>
+struct _LIBCPP_HIDDEN __traits_base;
+
+template <typename _Tp>
+struct _LIBCPP_HIDDEN __traits_base<_Tp, __enable_if_t<sizeof(_Tp) <= sizeof(uint32_t)>> {
+ using type = uint32_t;
+
+ /// The width estimation using a log10 algorithm.
+ ///
+ /// The algorithm is based on
+ /// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
+ /// Instead of using IntegerLogBase2 it uses __libcpp_clz. Since that
+ /// function requires its input to have at least one bit set the value of
+ /// zero is set to one. This means the first element of the lookup table is
+ /// zero.
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __width(_Tp __v) {
+ auto __t = (32 - std::__libcpp_clz(static_cast<type>(__v | 1))) * 1233 >> 12;
+ return __t - (__v < __itoa::__pow10_32[__t]) + 1;
+ }
+
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char* __convert(char* __p, _Tp __v) {
+ return __itoa::__base_10_u32(__p, __v);
+ }
+
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI decltype(__pow10_32)& __pow() {
+ return __itoa::__pow10_32;
+ }
+};
+
+template <typename _Tp>
+struct _LIBCPP_HIDDEN __traits_base<_Tp, __enable_if_t<sizeof(_Tp) == sizeof(uint64_t)>> {
+ using type = uint64_t;
+
+ /// The width estimation using a log10 algorithm.
+ ///
+ /// The algorithm is based on
+ /// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
+ /// Instead of using IntegerLogBase2 it uses __libcpp_clz. Since that
+ /// function requires its input to have at least one bit set the value of
+ /// zero is set to one. This means the first element of the lookup table is
+ /// zero.
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __width(_Tp __v) {
+ auto __t = (64 - std::__libcpp_clz(static_cast<type>(__v | 1))) * 1233 >> 12;
+ return __t - (__v < __itoa::__pow10_64[__t]) + 1;
+ }
+
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char* __convert(char* __p, _Tp __v) {
+ return __itoa::__base_10_u64(__p, __v);
+ }
+
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI decltype(__pow10_64)& __pow() {
+ return __itoa::__pow10_64;
+ }
+};
+
+# ifndef _LIBCPP_HAS_NO_INT128
+template <typename _Tp>
+struct _LIBCPP_HIDDEN __traits_base<_Tp, __enable_if_t<sizeof(_Tp) == sizeof(__uint128_t)> > {
+ using type = __uint128_t;
+
+ /// The width estimation using a log10 algorithm.
+ ///
+ /// The algorithm is based on
+ /// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
+ /// Instead of using IntegerLogBase2 it uses __libcpp_clz. Since that
+ /// function requires its input to have at least one bit set the value of
+ /// zero is set to one. This means the first element of the lookup table is
+ /// zero.
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __width(_Tp __v) {
+ _LIBCPP_ASSERT_INTERNAL(
+ __v > numeric_limits<uint64_t>::max(), "The optimizations for this algorithm fail when this isn't true.");
+ // There's always a bit set in the upper 64-bits.
+ auto __t = (128 - std::__libcpp_clz(static_cast<uint64_t>(__v >> 64))) * 1233 >> 12;
+ _LIBCPP_ASSERT_INTERNAL(__t >= __itoa::__pow10_128_offset, "Index out of bounds");
+ // __t is adjusted since the lookup table misses the lower entries.
+ return __t - (__v < __itoa::__pow10_128[__t - __itoa::__pow10_128_offset]) + 1;
+ }
+
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char* __convert(char* __p, _Tp __v) {
+ return __itoa::__base_10_u128(__p, __v);
+ }
+
+ // TODO FMT This pow function should get an index.
+ // By moving this to its own header it can be reused by the pow function in to_chars_base_10.
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI decltype(__pow10_128)& __pow() {
+ return __itoa::__pow10_128;
+ }
+};
+# endif
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool
+__mul_overflowed(unsigned char __a, _Tp __b, unsigned char& __r) {
+ auto __c = __a * __b;
+ __r = __c;
+ return __c > numeric_limits<unsigned char>::max();
+}
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool
+__mul_overflowed(unsigned short __a, _Tp __b, unsigned short& __r) {
+ auto __c = __a * __b;
+ __r = __c;
+ return __c > numeric_limits<unsigned short>::max();
+}
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool __mul_overflowed(_Tp __a, _Tp __b, _Tp& __r) {
+ static_assert(is_unsigned<_Tp>::value, "");
+ return __builtin_mul_overflow(__a, __b, &__r);
+}
+
+template <typename _Tp, typename _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool _LIBCPP_CONSTEXPR_SINCE_CXX23 __mul_overflowed(_Tp __a, _Up __b, _Tp& __r) {
+ return __itoa::__mul_overflowed(__a, static_cast<_Tp>(__b), __r);
+}
+
+template <typename _Tp>
+struct _LIBCPP_HIDDEN __traits : __traits_base<_Tp> {
+ static constexpr int digits = numeric_limits<_Tp>::digits10 + 1;
+ using __traits_base<_Tp>::__pow;
+ using typename __traits_base<_Tp>::type;
+
+ // precondition: at least one non-zero character available
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char const*
+ __read(char const* __p, char const* __ep, type& __a, type& __b) {
+ type __cprod[digits];
+ int __j = digits - 1;
+ int __i = digits;
+ do {
+ if (*__p < '0' || *__p > '9')
+ break;
+ __cprod[--__i] = *__p++ - '0';
+ } while (__p != __ep && __i != 0);
+
+ __a = __inner_product(__cprod + __i + 1, __cprod + __j, __pow() + 1, __cprod[__i]);
+ if (__itoa::__mul_overflowed(__cprod[__j], __pow()[__j - __i], __b))
+ --__p;
+ return __p;
+ }
+
+ template <typename _It1, typename _It2, class _Up>
+ static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI _Up
+ __inner_product(_It1 __first1, _It1 __last1, _It2 __first2, _Up __init) {
+ for (; __first1 < __last1; ++__first1, ++__first2)
+ __init = __init + *__first1 * *__first2;
+ return __init;
+ }
+};
+
+} // namespace __itoa
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI _Tp __complement(_Tp __x) {
+ static_assert(is_unsigned<_Tp>::value, "cast to unsigned first");
+ return _Tp(~__x + 1);
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_TRAITS
diff --git a/libcxx/include/__cxx03/__chrono/calendar.h b/libcxx/include/__cxx03/__chrono/calendar.h
new file mode 100644
index 00000000000000..bb1c5e7ebc8d0b
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/calendar.h
@@ -0,0 +1,44 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_CALENDAR_H
+#define _LIBCPP___CHRONO_CALENDAR_H
+
+#include <__chrono/duration.h>
+#include <__chrono/time_point.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+struct local_t {};
+template <class _Duration>
+using local_time = time_point<local_t, _Duration>;
+using local_seconds = local_time<seconds>;
+using local_days = local_time<days>;
+
+struct last_spec {
+ explicit last_spec() = default;
+};
+inline constexpr last_spec last{};
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_CALENDAR_H
diff --git a/libcxx/include/__cxx03/__chrono/concepts.h b/libcxx/include/__cxx03/__chrono/concepts.h
new file mode 100644
index 00000000000000..61ec256b23abb2
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/concepts.h
@@ -0,0 +1,36 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_CONCEPTS_H
+#define _LIBCPP___CHRONO_CONCEPTS_H
+
+#include <__chrono/hh_mm_ss.h>
+#include <__chrono/time_point.h>
+#include <__config>
+#include <__type_traits/is_specialization.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+concept __is_hh_mm_ss = __is_specialization_v<_Tp, chrono::hh_mm_ss>;
+
+template <class _Tp>
+concept __is_time_point = __is_specialization_v<_Tp, chrono::time_point>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHRONO_CONCEPTS_H
diff --git a/libcxx/include/__cxx03/__chrono/convert_to_timespec.h b/libcxx/include/__cxx03/__chrono/convert_to_timespec.h
new file mode 100644
index 00000000000000..11e0b826d05b4c
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/convert_to_timespec.h
@@ -0,0 +1,51 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_CONVERT_TO_TIMESPEC_H
+#define _LIBCPP___CHRONO_CONVERT_TO_TIMESPEC_H
+
+#include <__chrono/duration.h>
+#include <__config>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Convert a nanoseconds duration to the given TimeSpec type, which must have
+// the same properties as std::timespec.
+template <class _TimeSpec>
+_LIBCPP_HIDE_FROM_ABI inline _TimeSpec __convert_to_timespec(const chrono::nanoseconds& __ns) {
+ using namespace chrono;
+ seconds __s = duration_cast<seconds>(__ns);
+ _TimeSpec __ts;
+ typedef decltype(__ts.tv_sec) __ts_sec;
+ const __ts_sec __ts_sec_max = numeric_limits<__ts_sec>::max();
+
+ if (__s.count() < __ts_sec_max) {
+ __ts.tv_sec = static_cast<__ts_sec>(__s.count());
+ __ts.tv_nsec = static_cast<decltype(__ts.tv_nsec)>((__ns - __s).count());
+ } else {
+ __ts.tv_sec = __ts_sec_max;
+ __ts.tv_nsec = 999999999; // (10^9 - 1)
+ }
+
+ return __ts;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHRONO_CONVERT_TO_TIMESPEC_H
diff --git a/libcxx/include/__cxx03/__chrono/convert_to_tm.h b/libcxx/include/__cxx03/__chrono/convert_to_tm.h
new file mode 100644
index 00000000000000..3a51019b80784a
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/convert_to_tm.h
@@ -0,0 +1,202 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_CONVERT_TO_TM_H
+#define _LIBCPP___CHRONO_CONVERT_TO_TM_H
+
+#include <__chrono/calendar.h>
+#include <__chrono/concepts.h>
+#include <__chrono/day.h>
+#include <__chrono/duration.h>
+#include <__chrono/file_clock.h>
+#include <__chrono/hh_mm_ss.h>
+#include <__chrono/local_info.h>
+#include <__chrono/month.h>
+#include <__chrono/month_weekday.h>
+#include <__chrono/monthday.h>
+#include <__chrono/statically_widen.h>
+#include <__chrono/sys_info.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/time_point.h>
+#include <__chrono/weekday.h>
+#include <__chrono/year.h>
+#include <__chrono/year_month.h>
+#include <__chrono/year_month_day.h>
+#include <__chrono/year_month_weekday.h>
+#include <__chrono/zoned_time.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/format_error.h>
+#include <__memory/addressof.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_specialization.h>
+#include <cstdint>
+#include <ctime>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// Conerts a chrono date and weekday to a given _Tm type.
+//
+// This is an implementation detail for the function
+// template <class _Tm, class _ChronoT>
+// _Tm __convert_to_tm(const _ChronoT& __value)
+//
+// This manually converts the two values to the proper type. It is possible to
+// convert from sys_days to time_t and then to _Tm. But this leads to the Y2K
+// bug when time_t is a 32-bit signed integer. Chrono considers years beyond
+// the year 2038 valid, so instead do the transformation manually.
+template <class _Tm, class _Date>
+ requires(same_as<_Date, chrono::year_month_day> || same_as<_Date, chrono::year_month_day_last>)
+_LIBCPP_HIDE_FROM_ABI _Tm __convert_to_tm(const _Date& __date, chrono::weekday __weekday) {
+ _Tm __result = {};
+# ifdef __GLIBC__
+ __result.tm_zone = "UTC";
+# endif
+ __result.tm_year = static_cast<int>(__date.year()) - 1900;
+ __result.tm_mon = static_cast<unsigned>(__date.month()) - 1;
+ __result.tm_mday = static_cast<unsigned>(__date.day());
+ __result.tm_wday = static_cast<unsigned>(__weekday.c_encoding());
+ __result.tm_yday =
+ (static_cast<chrono::sys_days>(__date) -
+ static_cast<chrono::sys_days>(chrono::year_month_day{__date.year(), chrono::January, chrono::day{1}}))
+ .count();
+
+ return __result;
+}
+
+template <class _Tm, class _Duration>
+_LIBCPP_HIDE_FROM_ABI _Tm __convert_to_tm(const chrono::sys_time<_Duration> __tp) {
+ chrono::sys_days __days = chrono::floor<chrono::days>(__tp);
+ chrono::year_month_day __ymd{__days};
+
+ _Tm __result = std::__convert_to_tm<_Tm>(chrono::year_month_day{__ymd}, chrono::weekday{__days});
+
+ uint64_t __sec =
+ chrono::duration_cast<chrono::seconds>(__tp - chrono::time_point_cast<chrono::seconds>(__days)).count();
+ __sec %= 24 * 3600;
+ __result.tm_hour = __sec / 3600;
+ __sec %= 3600;
+ __result.tm_min = __sec / 60;
+ __result.tm_sec = __sec % 60;
+
+ return __result;
+}
+
+// Convert a chrono (calendar) time point, or dururation to the given _Tm type,
+// which must have the same properties as std::tm.
+template <class _Tm, class _ChronoT>
+_LIBCPP_HIDE_FROM_ABI _Tm __convert_to_tm(const _ChronoT& __value) {
+ _Tm __result = {};
+# ifdef __GLIBC__
+ __result.tm_zone = "UTC";
+# endif
+
+ if constexpr (__is_time_point<_ChronoT>) {
+ if constexpr (same_as<typename _ChronoT::clock, chrono::system_clock>)
+ return std::__convert_to_tm<_Tm>(__value);
+ else if constexpr (same_as<typename _ChronoT::clock, chrono::file_clock>)
+ return std::__convert_to_tm<_Tm>(_ChronoT::clock::to_sys(__value));
+ else if constexpr (same_as<typename _ChronoT::clock, chrono::local_t>)
+ return std::__convert_to_tm<_Tm>(chrono::sys_time<typename _ChronoT::duration>{__value.time_since_epoch()});
+ else
+ static_assert(sizeof(_ChronoT) == 0, "TODO: Add the missing clock specialization");
+ } else if constexpr (chrono::__is_duration<_ChronoT>::value) {
+ // [time.format]/6
+ // ... However, if a flag refers to a "time of day" (e.g. %H, %I, %p,
+ // etc.), then a specialization of duration is interpreted as the time of
+ // day elapsed since midnight.
+
+ // Not all values can be converted to hours, it may run into ratio
+ // conversion errors. In that case the conversion to seconds works.
+ if constexpr (is_convertible_v<_ChronoT, chrono::hours>) {
+ auto __hour = chrono::floor<chrono::hours>(__value);
+ auto __sec = chrono::duration_cast<chrono::seconds>(__value - __hour);
+ __result.tm_hour = __hour.count() % 24;
+ __result.tm_min = __sec.count() / 60;
+ __result.tm_sec = __sec.count() % 60;
+ } else {
+ uint64_t __sec = chrono::duration_cast<chrono::seconds>(__value).count();
+ __sec %= 24 * 3600;
+ __result.tm_hour = __sec / 3600;
+ __sec %= 3600;
+ __result.tm_min = __sec / 60;
+ __result.tm_sec = __sec % 60;
+ }
+ } else if constexpr (same_as<_ChronoT, chrono::day>)
+ __result.tm_mday = static_cast<unsigned>(__value);
+ else if constexpr (same_as<_ChronoT, chrono::month>)
+ __result.tm_mon = static_cast<unsigned>(__value) - 1;
+ else if constexpr (same_as<_ChronoT, chrono::year>)
+ __result.tm_year = static_cast<int>(__value) - 1900;
+ else if constexpr (same_as<_ChronoT, chrono::weekday>)
+ __result.tm_wday = __value.c_encoding();
+ else if constexpr (same_as<_ChronoT, chrono::weekday_indexed> || same_as<_ChronoT, chrono::weekday_last>)
+ __result.tm_wday = __value.weekday().c_encoding();
+ else if constexpr (same_as<_ChronoT, chrono::month_day>) {
+ __result.tm_mday = static_cast<unsigned>(__value.day());
+ __result.tm_mon = static_cast<unsigned>(__value.month()) - 1;
+ } else if constexpr (same_as<_ChronoT, chrono::month_day_last>) {
+ __result.tm_mon = static_cast<unsigned>(__value.month()) - 1;
+ } else if constexpr (same_as<_ChronoT, chrono::month_weekday> || same_as<_ChronoT, chrono::month_weekday_last>) {
+ __result.tm_wday = __value.weekday_indexed().weekday().c_encoding();
+ __result.tm_mon = static_cast<unsigned>(__value.month()) - 1;
+ } else if constexpr (same_as<_ChronoT, chrono::year_month>) {
+ __result.tm_year = static_cast<int>(__value.year()) - 1900;
+ __result.tm_mon = static_cast<unsigned>(__value.month()) - 1;
+ } else if constexpr (same_as<_ChronoT, chrono::year_month_day> || same_as<_ChronoT, chrono::year_month_day_last>) {
+ return std::__convert_to_tm<_Tm>(
+ chrono::year_month_day{__value}, chrono::weekday{static_cast<chrono::sys_days>(__value)});
+ } else if constexpr (same_as<_ChronoT, chrono::year_month_weekday> ||
+ same_as<_ChronoT, chrono::year_month_weekday_last>) {
+ return std::__convert_to_tm<_Tm>(chrono::year_month_day{static_cast<chrono::sys_days>(__value)}, __value.weekday());
+ } else if constexpr (__is_hh_mm_ss<_ChronoT>) {
+ __result.tm_sec = __value.seconds().count();
+ __result.tm_min = __value.minutes().count();
+ // In libc++ hours is stored as a long. The type in std::tm is an int. So
+ // the overflow can only occur when hour uses more bits than an int
+ // provides.
+ if constexpr (sizeof(std::chrono::hours::rep) > sizeof(__result.tm_hour))
+ if (__value.hours().count() > std::numeric_limits<decltype(__result.tm_hour)>::max())
+ std::__throw_format_error("Formatting hh_mm_ss, encountered an hour overflow");
+ __result.tm_hour = __value.hours().count();
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ } else if constexpr (same_as<_ChronoT, chrono::sys_info>) {
+ // Has no time information.
+ } else if constexpr (same_as<_ChronoT, chrono::local_info>) {
+ // Has no time information.
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ } else if constexpr (__is_specialization_v<_ChronoT, chrono::zoned_time>) {
+ return std::__convert_to_tm<_Tm>(
+ chrono::sys_time<typename _ChronoT::duration>{__value.get_local_time().time_since_epoch()});
+# endif
+# endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ } else
+ static_assert(sizeof(_ChronoT) == 0, "Add the missing type specialization");
+
+ return __result;
+}
+
+#endif // if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHRONO_CONVERT_TO_TM_H
diff --git a/libcxx/include/__cxx03/__chrono/day.h b/libcxx/include/__cxx03/__chrono/day.h
new file mode 100644
index 00000000000000..7342084b08c886
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/day.h
@@ -0,0 +1,99 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_DAY_H
+#define _LIBCPP___CHRONO_DAY_H
+
+#include <__chrono/duration.h>
+#include <__config>
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class day {
+private:
+ unsigned char __d_;
+
+public:
+ day() = default;
+ _LIBCPP_HIDE_FROM_ABI explicit inline constexpr day(unsigned __val) noexcept
+ : __d_(static_cast<unsigned char>(__val)) {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr day& operator++() noexcept {
+ ++__d_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr day operator++(int) noexcept {
+ day __tmp = *this;
+ ++(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr day& operator--() noexcept {
+ --__d_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr day operator--(int) noexcept {
+ day __tmp = *this;
+ --(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr day& operator+=(const days& __dd) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr day& operator-=(const days& __dd) noexcept;
+ _LIBCPP_HIDE_FROM_ABI explicit inline constexpr operator unsigned() const noexcept { return __d_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __d_ >= 1 && __d_ <= 31; }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(const day& __lhs, const day& __rhs) noexcept {
+ return static_cast<unsigned>(__lhs) == static_cast<unsigned>(__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering operator<=>(const day& __lhs, const day& __rhs) noexcept {
+ return static_cast<unsigned>(__lhs) <=> static_cast<unsigned>(__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr day operator+(const day& __lhs, const days& __rhs) noexcept {
+ return day(static_cast<unsigned>(__lhs) + __rhs.count());
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr day operator+(const days& __lhs, const day& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr day operator-(const day& __lhs, const days& __rhs) noexcept {
+ return __lhs + -__rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr days operator-(const day& __lhs, const day& __rhs) noexcept {
+ return days(static_cast<int>(static_cast<unsigned>(__lhs)) - static_cast<int>(static_cast<unsigned>(__rhs)));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr day& day::operator+=(const days& __dd) noexcept {
+ *this = *this + __dd;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr day& day::operator-=(const days& __dd) noexcept {
+ *this = *this - __dd;
+ return *this;
+}
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_DAY_H
diff --git a/libcxx/include/__cxx03/__chrono/duration.h b/libcxx/include/__cxx03/__chrono/duration.h
new file mode 100644
index 00000000000000..1e36d7342836f6
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/duration.h
@@ -0,0 +1,550 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_DURATION_H
+#define _LIBCPP___CHRONO_DURATION_H
+
+#include <__compare/ordering.h>
+#include <__compare/three_way_comparable.h>
+#include <__config>
+#include <__type_traits/common_type.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_floating_point.h>
+#include <limits>
+#include <ratio>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+template <class _Rep, class _Period = ratio<1> >
+class _LIBCPP_TEMPLATE_VIS duration;
+
+template <class _Tp>
+struct __is_duration : false_type {};
+
+template <class _Rep, class _Period>
+struct __is_duration<duration<_Rep, _Period> > : true_type {};
+
+template <class _Rep, class _Period>
+struct __is_duration<const duration<_Rep, _Period> > : true_type {};
+
+template <class _Rep, class _Period>
+struct __is_duration<volatile duration<_Rep, _Period> > : true_type {};
+
+template <class _Rep, class _Period>
+struct __is_duration<const volatile duration<_Rep, _Period> > : true_type {};
+
+} // namespace chrono
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+struct _LIBCPP_TEMPLATE_VIS common_type<chrono::duration<_Rep1, _Period1>, chrono::duration<_Rep2, _Period2> > {
+ typedef chrono::duration<typename common_type<_Rep1, _Rep2>::type, typename __ratio_gcd<_Period1, _Period2>::type>
+ type;
+};
+
+namespace chrono {
+
+// duration_cast
+
+template <class _FromDuration,
+ class _ToDuration,
+ class _Period = typename ratio_divide<typename _FromDuration::period, typename _ToDuration::period>::type,
+ bool = _Period::num == 1,
+ bool = _Period::den == 1>
+struct __duration_cast;
+
+template <class _FromDuration, class _ToDuration, class _Period>
+struct __duration_cast<_FromDuration, _ToDuration, _Period, true, true> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToDuration operator()(const _FromDuration& __fd) const {
+ return _ToDuration(static_cast<typename _ToDuration::rep>(__fd.count()));
+ }
+};
+
+template <class _FromDuration, class _ToDuration, class _Period>
+struct __duration_cast<_FromDuration, _ToDuration, _Period, true, false> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToDuration operator()(const _FromDuration& __fd) const {
+ typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
+ return _ToDuration(
+ static_cast<typename _ToDuration::rep>(static_cast<_Ct>(__fd.count()) / static_cast<_Ct>(_Period::den)));
+ }
+};
+
+template <class _FromDuration, class _ToDuration, class _Period>
+struct __duration_cast<_FromDuration, _ToDuration, _Period, false, true> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToDuration operator()(const _FromDuration& __fd) const {
+ typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
+ return _ToDuration(
+ static_cast<typename _ToDuration::rep>(static_cast<_Ct>(__fd.count()) * static_cast<_Ct>(_Period::num)));
+ }
+};
+
+template <class _FromDuration, class _ToDuration, class _Period>
+struct __duration_cast<_FromDuration, _ToDuration, _Period, false, false> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToDuration operator()(const _FromDuration& __fd) const {
+ typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
+ return _ToDuration(static_cast<typename _ToDuration::rep>(
+ static_cast<_Ct>(__fd.count()) * static_cast<_Ct>(_Period::num) / static_cast<_Ct>(_Period::den)));
+ }
+};
+
+template <class _ToDuration, class _Rep, class _Period, __enable_if_t<__is_duration<_ToDuration>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToDuration duration_cast(const duration<_Rep, _Period>& __fd) {
+ return __duration_cast<duration<_Rep, _Period>, _ToDuration>()(__fd);
+}
+
+template <class _Rep>
+struct _LIBCPP_TEMPLATE_VIS treat_as_floating_point : is_floating_point<_Rep> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Rep>
+inline constexpr bool treat_as_floating_point_v = treat_as_floating_point<_Rep>::value;
+#endif
+
+template <class _Rep>
+struct _LIBCPP_TEMPLATE_VIS duration_values {
+public:
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR _Rep zero() _NOEXCEPT { return _Rep(0); }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR _Rep max() _NOEXCEPT { return numeric_limits<_Rep>::max(); }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR _Rep min() _NOEXCEPT { return numeric_limits<_Rep>::lowest(); }
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _ToDuration, class _Rep, class _Period, enable_if_t<__is_duration<_ToDuration>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToDuration floor(const duration<_Rep, _Period>& __d) {
+ _ToDuration __t = chrono::duration_cast<_ToDuration>(__d);
+ if (__t > __d)
+ __t = __t - _ToDuration{1};
+ return __t;
+}
+
+template <class _ToDuration, class _Rep, class _Period, enable_if_t<__is_duration<_ToDuration>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToDuration ceil(const duration<_Rep, _Period>& __d) {
+ _ToDuration __t = chrono::duration_cast<_ToDuration>(__d);
+ if (__t < __d)
+ __t = __t + _ToDuration{1};
+ return __t;
+}
+
+template <class _ToDuration, class _Rep, class _Period, enable_if_t<__is_duration<_ToDuration>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToDuration round(const duration<_Rep, _Period>& __d) {
+ _ToDuration __lower = chrono::floor<_ToDuration>(__d);
+ _ToDuration __upper = __lower + _ToDuration{1};
+ auto __lower_diff = __d - __lower;
+ auto __upper_diff = __upper - __d;
+ if (__lower_diff < __upper_diff)
+ return __lower;
+ if (__lower_diff > __upper_diff)
+ return __upper;
+ return __lower.count() & 1 ? __upper : __lower;
+}
+#endif
+
+// duration
+
+template <class _Rep, class _Period>
+class _LIBCPP_TEMPLATE_VIS duration {
+ static_assert(!__is_duration<_Rep>::value, "A duration representation can not be a duration");
+ static_assert(__is_ratio<_Period>::value, "Second template parameter of duration must be a std::ratio");
+ static_assert(_Period::num > 0, "duration period must be positive");
+
+ template <class _R1, class _R2>
+ struct __no_overflow {
+ private:
+ static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
+ static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
+ static const intmax_t __n1 = _R1::num / __gcd_n1_n2;
+ static const intmax_t __d1 = _R1::den / __gcd_d1_d2;
+ static const intmax_t __n2 = _R2::num / __gcd_n1_n2;
+ static const intmax_t __d2 = _R2::den / __gcd_d1_d2;
+ static const intmax_t max = -((intmax_t(1) << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1);
+
+ template <intmax_t _Xp, intmax_t _Yp, bool __overflow>
+ struct __mul // __overflow == false
+ {
+ static const intmax_t value = _Xp * _Yp;
+ };
+
+ template <intmax_t _Xp, intmax_t _Yp>
+ struct __mul<_Xp, _Yp, true> {
+ static const intmax_t value = 1;
+ };
+
+ public:
+ static const bool value = (__n1 <= max / __d2) && (__n2 <= max / __d1);
+ typedef ratio<__mul<__n1, __d2, !value>::value, __mul<__n2, __d1, !value>::value> type;
+ };
+
+public:
+ typedef _Rep rep;
+ typedef typename _Period::type period;
+
+private:
+ rep __rep_;
+
+public:
+#ifndef _LIBCPP_CXX03_LANG
+ constexpr duration() = default;
+#else
+ _LIBCPP_HIDE_FROM_ABI duration() {}
+#endif
+
+ template <class _Rep2,
+ __enable_if_t<is_convertible<const _Rep2&, rep>::value &&
+ (treat_as_floating_point<rep>::value || !treat_as_floating_point<_Rep2>::value),
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit duration(const _Rep2& __r) : __rep_(__r) {}
+
+ // conversions
+ template <class _Rep2,
+ class _Period2,
+ __enable_if_t<__no_overflow<_Period2, period>::value && (treat_as_floating_point<rep>::value ||
+ (__no_overflow<_Period2, period>::type::den == 1 &&
+ !treat_as_floating_point<_Rep2>::value)),
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR duration(const duration<_Rep2, _Period2>& __d)
+ : __rep_(chrono::duration_cast<duration>(__d).count()) {}
+
+ // observer
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR rep count() const { return __rep_; }
+
+ // arithmetic
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR typename common_type<duration>::type operator+() const {
+ return typename common_type<duration>::type(*this);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR typename common_type<duration>::type operator-() const {
+ return typename common_type<duration>::type(-__rep_);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration& operator++() {
+ ++__rep_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration operator++(int) { return duration(__rep_++); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration& operator--() {
+ --__rep_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration operator--(int) { return duration(__rep_--); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration& operator+=(const duration& __d) {
+ __rep_ += __d.count();
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration& operator-=(const duration& __d) {
+ __rep_ -= __d.count();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration& operator*=(const rep& __rhs) {
+ __rep_ *= __rhs;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration& operator/=(const rep& __rhs) {
+ __rep_ /= __rhs;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration& operator%=(const rep& __rhs) {
+ __rep_ %= __rhs;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 duration& operator%=(const duration& __rhs) {
+ __rep_ %= __rhs.count();
+ return *this;
+ }
+
+ // special values
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR duration zero() _NOEXCEPT {
+ return duration(duration_values<rep>::zero());
+ }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR duration min() _NOEXCEPT {
+ return duration(duration_values<rep>::min());
+ }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR duration max() _NOEXCEPT {
+ return duration(duration_values<rep>::max());
+ }
+};
+
+typedef duration<long long, nano> nanoseconds;
+typedef duration<long long, micro> microseconds;
+typedef duration<long long, milli> milliseconds;
+typedef duration<long long > seconds;
+typedef duration< long, ratio< 60> > minutes;
+typedef duration< long, ratio<3600> > hours;
+#if _LIBCPP_STD_VER >= 20
+typedef duration< int, ratio_multiply<ratio<24>, hours::period>> days;
+typedef duration< int, ratio_multiply<ratio<7>, days::period>> weeks;
+typedef duration< int, ratio_multiply<ratio<146097, 400>, days::period>> years;
+typedef duration< int, ratio_divide<years::period, ratio<12>>> months;
+#endif
+// Duration ==
+
+template <class _LhsDuration, class _RhsDuration>
+struct __duration_eq {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs) const {
+ typedef typename common_type<_LhsDuration, _RhsDuration>::type _Ct;
+ return _Ct(__lhs).count() == _Ct(__rhs).count();
+ }
+};
+
+template <class _LhsDuration>
+struct __duration_eq<_LhsDuration, _LhsDuration> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs) const {
+ return __lhs.count() == __rhs.count();
+ }
+};
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator==(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ return __duration_eq<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >()(__lhs, __rhs);
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+// Duration !=
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator!=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ return !(__lhs == __rhs);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+// Duration <
+
+template <class _LhsDuration, class _RhsDuration>
+struct __duration_lt {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs) const {
+ typedef typename common_type<_LhsDuration, _RhsDuration>::type _Ct;
+ return _Ct(__lhs).count() < _Ct(__rhs).count();
+ }
+};
+
+template <class _LhsDuration>
+struct __duration_lt<_LhsDuration, _LhsDuration> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs) const {
+ return __lhs.count() < __rhs.count();
+ }
+};
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator<(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ return __duration_lt<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >()(__lhs, __rhs);
+}
+
+// Duration >
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator>(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ return __rhs < __lhs;
+}
+
+// Duration <=
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator<=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ return !(__rhs < __lhs);
+}
+
+// Duration >=
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator>=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ return !(__lhs < __rhs);
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+ requires three_way_comparable<common_type_t<_Rep1, _Rep2>>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+operator<=>(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ using _Ct = common_type_t<duration<_Rep1, _Period1>, duration<_Rep2, _Period2>>;
+ return _Ct(__lhs).count() <=> _Ct(__rhs).count();
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+// Duration +
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
+operator+(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
+ return _Cd(_Cd(__lhs).count() + _Cd(__rhs).count());
+}
+
+// Duration -
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
+operator-(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
+ return _Cd(_Cd(__lhs).count() - _Cd(__rhs).count());
+}
+
+// Duration *
+
+template <class _Rep1,
+ class _Period,
+ class _Rep2,
+ __enable_if_t<is_convertible<const _Rep2&, typename common_type<_Rep1, _Rep2>::type>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR duration<typename common_type<_Rep1, _Rep2>::type, _Period>
+operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s) {
+ typedef typename common_type<_Rep1, _Rep2>::type _Cr;
+ typedef duration<_Cr, _Period> _Cd;
+ return _Cd(_Cd(__d).count() * static_cast<_Cr>(__s));
+}
+
+template <class _Rep1,
+ class _Period,
+ class _Rep2,
+ __enable_if_t<is_convertible<const _Rep1&, typename common_type<_Rep1, _Rep2>::type>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR duration<typename common_type<_Rep1, _Rep2>::type, _Period>
+operator*(const _Rep1& __s, const duration<_Rep2, _Period>& __d) {
+ return __d * __s;
+}
+
+// Duration /
+
+template <class _Rep1,
+ class _Period,
+ class _Rep2,
+ __enable_if_t<!__is_duration<_Rep2>::value &&
+ is_convertible<const _Rep2&, typename common_type<_Rep1, _Rep2>::type>::value,
+ int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR duration<typename common_type<_Rep1, _Rep2>::type, _Period>
+operator/(const duration<_Rep1, _Period>& __d, const _Rep2& __s) {
+ typedef typename common_type<_Rep1, _Rep2>::type _Cr;
+ typedef duration<_Cr, _Period> _Cd;
+ return _Cd(_Cd(__d).count() / static_cast<_Cr>(__s));
+}
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR typename common_type<_Rep1, _Rep2>::type
+operator/(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Ct;
+ return _Ct(__lhs).count() / _Ct(__rhs).count();
+}
+
+// Duration %
+
+template <class _Rep1,
+ class _Period,
+ class _Rep2,
+ __enable_if_t<!__is_duration<_Rep2>::value &&
+ is_convertible<const _Rep2&, typename common_type<_Rep1, _Rep2>::type>::value,
+ int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR duration<typename common_type<_Rep1, _Rep2>::type, _Period>
+operator%(const duration<_Rep1, _Period>& __d, const _Rep2& __s) {
+ typedef typename common_type<_Rep1, _Rep2>::type _Cr;
+ typedef duration<_Cr, _Period> _Cd;
+ return _Cd(_Cd(__d).count() % static_cast<_Cr>(__s));
+}
+
+template <class _Rep1, class _Period1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
+operator%(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ typedef typename common_type<_Rep1, _Rep2>::type _Cr;
+ typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
+ return _Cd(static_cast<_Cr>(_Cd(__lhs).count()) % static_cast<_Cr>(_Cd(__rhs).count()));
+}
+
+} // namespace chrono
+
+#if _LIBCPP_STD_VER >= 14
+// Suffixes for duration literals [time.duration.literals]
+inline namespace literals {
+inline namespace chrono_literals {
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::hours operator""h(unsigned long long __h) {
+ return chrono::hours(static_cast<chrono::hours::rep>(__h));
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::duration<long double, ratio<3600, 1>> operator""h(long double __h) {
+ return chrono::duration<long double, ratio<3600, 1>>(__h);
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::minutes operator""min(unsigned long long __m) {
+ return chrono::minutes(static_cast<chrono::minutes::rep>(__m));
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::duration<long double, ratio<60, 1>> operator""min(long double __m) {
+ return chrono::duration<long double, ratio<60, 1>>(__m);
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::seconds operator""s(unsigned long long __s) {
+ return chrono::seconds(static_cast<chrono::seconds::rep>(__s));
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::duration<long double> operator""s(long double __s) {
+ return chrono::duration<long double>(__s);
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::milliseconds operator""ms(unsigned long long __ms) {
+ return chrono::milliseconds(static_cast<chrono::milliseconds::rep>(__ms));
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::duration<long double, milli> operator""ms(long double __ms) {
+ return chrono::duration<long double, milli>(__ms);
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::microseconds operator""us(unsigned long long __us) {
+ return chrono::microseconds(static_cast<chrono::microseconds::rep>(__us));
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::duration<long double, micro> operator""us(long double __us) {
+ return chrono::duration<long double, micro>(__us);
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::nanoseconds operator""ns(unsigned long long __ns) {
+ return chrono::nanoseconds(static_cast<chrono::nanoseconds::rep>(__ns));
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::duration<long double, nano> operator""ns(long double __ns) {
+ return chrono::duration<long double, nano>(__ns);
+}
+
+} // namespace chrono_literals
+} // namespace literals
+
+namespace chrono { // hoist the literals into namespace std::chrono
+using namespace literals::chrono_literals;
+} // namespace chrono
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP___CHRONO_DURATION_H
diff --git a/libcxx/include/__cxx03/__chrono/exception.h b/libcxx/include/__cxx03/__chrono/exception.h
new file mode 100644
index 00000000000000..266f8fac441760
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/exception.h
@@ -0,0 +1,135 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_EXCEPTION_H
+#define _LIBCPP___CHRONO_EXCEPTION_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__chrono/calendar.h>
+# include <__chrono/local_info.h>
+# include <__chrono/time_point.h>
+# include <__config>
+# include <__configuration/availability.h>
+# include <__verbose_abort>
+# include <format>
+# include <stdexcept>
+# include <string>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20
+
+namespace chrono {
+
+class nonexistent_local_time : public runtime_error {
+public:
+ template <class _Duration>
+ _LIBCPP_HIDE_FROM_ABI nonexistent_local_time(const local_time<_Duration>& __time, const local_info& __info)
+ : runtime_error{__create_message(__time, __info)} {
+ // [time.zone.exception.nonexist]/2
+ // Preconditions: i.result == local_info::nonexistent is true.
+ // The value of __info.result is not used.
+ _LIBCPP_ASSERT_PEDANTIC(__info.result == local_info::nonexistent,
+ "creating an nonexistent_local_time from a local_info that is not non-existent");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI nonexistent_local_time(const nonexistent_local_time&) = default;
+ _LIBCPP_HIDE_FROM_ABI nonexistent_local_time& operator=(const nonexistent_local_time&) = default;
+
+ _LIBCPP_AVAILABILITY_TZDB _LIBCPP_EXPORTED_FROM_ABI ~nonexistent_local_time() override; // exported as key function
+
+private:
+ template <class _Duration>
+ _LIBCPP_HIDE_FROM_ABI string __create_message(const local_time<_Duration>& __time, const local_info& __info) {
+ return std::format(
+ R"({} is in a gap between
+{} {} and
+{} {} which are both equivalent to
+{} UTC)",
+ __time,
+ local_seconds{__info.first.end.time_since_epoch()} + __info.first.offset,
+ __info.first.abbrev,
+ local_seconds{__info.second.begin.time_since_epoch()} + __info.second.offset,
+ __info.second.abbrev,
+ __info.first.end);
+ }
+};
+
+template <class _Duration>
+_LIBCPP_NORETURN _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI void __throw_nonexistent_local_time(
+ [[maybe_unused]] const local_time<_Duration>& __time, [[maybe_unused]] const local_info& __info) {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw nonexistent_local_time(__time, __info);
+# else
+ _LIBCPP_VERBOSE_ABORT("nonexistent_local_time was thrown in -fno-exceptions mode");
+# endif
+}
+
+class ambiguous_local_time : public runtime_error {
+public:
+ template <class _Duration>
+ _LIBCPP_HIDE_FROM_ABI ambiguous_local_time(const local_time<_Duration>& __time, const local_info& __info)
+ : runtime_error{__create_message(__time, __info)} {
+ // [time.zone.exception.ambig]/2
+ // Preconditions: i.result == local_info::ambiguous is true.
+ // The value of __info.result is not used.
+ _LIBCPP_ASSERT_PEDANTIC(__info.result == local_info::ambiguous,
+ "creating an ambiguous_local_time from a local_info that is not ambiguous");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ambiguous_local_time(const ambiguous_local_time&) = default;
+ _LIBCPP_HIDE_FROM_ABI ambiguous_local_time& operator=(const ambiguous_local_time&) = default;
+
+ _LIBCPP_AVAILABILITY_TZDB _LIBCPP_EXPORTED_FROM_ABI ~ambiguous_local_time() override; // exported as key function
+
+private:
+ template <class _Duration>
+ _LIBCPP_HIDE_FROM_ABI string __create_message(const local_time<_Duration>& __time, const local_info& __info) {
+ return std::format(
+ // There are two spaces after the full-stop; this has been verified
+ // in the sources of the Standard.
+ R"({0} is ambiguous. It could be
+{0} {1} == {2} UTC or
+{0} {3} == {4} UTC)",
+ __time,
+ __info.first.abbrev,
+ __time - __info.first.offset,
+ __info.second.abbrev,
+ __time - __info.second.offset);
+ }
+};
+
+template <class _Duration>
+_LIBCPP_NORETURN _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI void __throw_ambiguous_local_time(
+ [[maybe_unused]] const local_time<_Duration>& __time, [[maybe_unused]] const local_info& __info) {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw ambiguous_local_time(__time, __info);
+# else
+ _LIBCPP_VERBOSE_ABORT("ambiguous_local_time was thrown in -fno-exceptions mode");
+# endif
+}
+
+} // namespace chrono
+
+# endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_EXCEPTION_H
diff --git a/libcxx/include/__cxx03/__chrono/file_clock.h b/libcxx/include/__cxx03/__chrono/file_clock.h
new file mode 100644
index 00000000000000..4dd3f88ce5ba4b
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/file_clock.h
@@ -0,0 +1,80 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_FILE_CLOCK_H
+#define _LIBCPP___CHRONO_FILE_CLOCK_H
+
+#include <__chrono/duration.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/time_point.h>
+#include <__config>
+#include <ratio>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+struct _FilesystemClock;
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+#endif // !_LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+// [time.clock.file], type file_clock
+using file_clock = filesystem::_FilesystemClock;
+
+template <class _Duration>
+using file_time = time_point<file_clock, _Duration>;
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#ifndef _LIBCPP_CXX03_LANG
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+struct _FilesystemClock {
+# if !defined(_LIBCPP_HAS_NO_INT128)
+ typedef __int128_t rep;
+ typedef nano period;
+# else
+ typedef long long rep;
+ typedef nano period;
+# endif
+
+ typedef chrono::duration<rep, period> duration;
+ typedef chrono::time_point<_FilesystemClock> time_point;
+
+ _LIBCPP_EXPORTED_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX14 const bool is_steady = false;
+
+ _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_EXPORTED_FROM_ABI static time_point now() noexcept;
+
+# if _LIBCPP_STD_VER >= 20
+ template <class _Duration>
+ _LIBCPP_HIDE_FROM_ABI static chrono::sys_time<_Duration> to_sys(const chrono::file_time<_Duration>& __t) {
+ return chrono::sys_time<_Duration>(__t.time_since_epoch());
+ }
+
+ template <class _Duration>
+ _LIBCPP_HIDE_FROM_ABI static chrono::file_time<_Duration> from_sys(const chrono::sys_time<_Duration>& __t) {
+ return chrono::file_time<_Duration>(__t.time_since_epoch());
+ }
+# endif // _LIBCPP_STD_VER >= 20
+};
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+#endif // !_LIBCPP_CXX03_LANG
+
+#endif // _LIBCPP___CHRONO_FILE_CLOCK_H
diff --git a/libcxx/include/__cxx03/__chrono/formatter.h b/libcxx/include/__cxx03/__chrono/formatter.h
new file mode 100644
index 00000000000000..449c415e957602
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/formatter.h
@@ -0,0 +1,990 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_FORMATTER_H
+#define _LIBCPP___CHRONO_FORMATTER_H
+
+#include <__algorithm/ranges_copy.h>
+#include <__chrono/calendar.h>
+#include <__chrono/concepts.h>
+#include <__chrono/convert_to_tm.h>
+#include <__chrono/day.h>
+#include <__chrono/duration.h>
+#include <__chrono/file_clock.h>
+#include <__chrono/hh_mm_ss.h>
+#include <__chrono/local_info.h>
+#include <__chrono/month.h>
+#include <__chrono/month_weekday.h>
+#include <__chrono/monthday.h>
+#include <__chrono/ostream.h>
+#include <__chrono/parser_std_format_spec.h>
+#include <__chrono/statically_widen.h>
+#include <__chrono/sys_info.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/time_point.h>
+#include <__chrono/weekday.h>
+#include <__chrono/year.h>
+#include <__chrono/year_month.h>
+#include <__chrono/year_month_day.h>
+#include <__chrono/year_month_weekday.h>
+#include <__chrono/zoned_time.h>
+#include <__concepts/arithmetic.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_error.h>
+#include <__format/format_functions.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/parser_std_format_spec.h>
+#include <__format/write_escaped.h>
+#include <__memory/addressof.h>
+#include <__type_traits/is_specialization.h>
+#include <cmath>
+#include <ctime>
+#include <limits>
+#include <sstream>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __formatter {
+
+/// Formats a time based on a tm struct.
+///
+/// This formatter passes the formatting to time_put which uses strftime. When
+/// the value is outside the valid range it's unspecified what strftime will
+/// output. For example weekday 8 can print 1 when the day is processed modulo
+/// 7 since that handles the Sunday for 0-based weekday. It can also print 8 if
+/// 7 is handled as a special case.
+///
+/// The Standard doesn't specify what to do in this case so the result depends
+/// on the result of the underlying code.
+///
+/// \pre When the (abbreviated) weekday or month name are used, the caller
+/// validates whether the value is valid. So the caller handles that
+/// requirement of Table 97: Meaning of conversion specifiers
+/// [tab:time.format.spec].
+///
+/// When no chrono-specs are provided it uses the stream formatter.
+
+// For tiny ratios it's not possible to convert a duration to a hh_mm_ss. This
+// fails compile-time due to the limited precision of the ratio (64-bit is too
+// small). Therefore a duration uses its own conversion.
+template <class _CharT, class _Rep, class _Period>
+_LIBCPP_HIDE_FROM_ABI void
+__format_sub_seconds(basic_stringstream<_CharT>& __sstr, const chrono::duration<_Rep, _Period>& __value) {
+ __sstr << std::use_facet<numpunct<_CharT>>(__sstr.getloc()).decimal_point();
+
+ using __duration = chrono::duration<_Rep, _Period>;
+
+ auto __fraction = __value - chrono::duration_cast<chrono::seconds>(__value);
+ // Converts a negative fraction to its positive value.
+ if (__value < chrono::seconds{0} && __fraction != __duration{0})
+ __fraction += chrono::seconds{1};
+ if constexpr (chrono::treat_as_floating_point_v<_Rep>)
+ // When the floating-point value has digits itself they are ignored based
+ // on the wording in [tab:time.format.spec]
+ // If the precision of the input cannot be exactly represented with
+ // seconds, then the format is a decimal floating-point number with a
+ // fixed format and a precision matching that of the precision of the
+ // input (or to a microseconds precision if the conversion to
+ // floating-point decimal seconds cannot be made within 18 fractional
+ // digits).
+ //
+ // This matches the behaviour of MSVC STL, fmtlib interprets this
+ // differently and uses 3 decimals.
+ // https://godbolt.org/z/6dsbnW8ba
+ std::format_to(std::ostreambuf_iterator<_CharT>{__sstr},
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{:0{}.0f}"),
+ chrono::duration_cast<typename chrono::hh_mm_ss<__duration>::precision>(__fraction).count(),
+ chrono::hh_mm_ss<__duration>::fractional_width);
+ else
+ std::format_to(std::ostreambuf_iterator<_CharT>{__sstr},
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{:0{}}"),
+ chrono::duration_cast<typename chrono::hh_mm_ss<__duration>::precision>(__fraction).count(),
+ chrono::hh_mm_ss<__duration>::fractional_width);
+}
+
+template <class _CharT, __is_time_point _Tp>
+_LIBCPP_HIDE_FROM_ABI void __format_sub_seconds(basic_stringstream<_CharT>& __sstr, const _Tp& __value) {
+ __formatter::__format_sub_seconds(__sstr, __value.time_since_epoch());
+}
+
+template <class _CharT, class _Duration>
+_LIBCPP_HIDE_FROM_ABI void
+__format_sub_seconds(basic_stringstream<_CharT>& __sstr, const chrono::hh_mm_ss<_Duration>& __value) {
+ __sstr << std::use_facet<numpunct<_CharT>>(__sstr.getloc()).decimal_point();
+ if constexpr (chrono::treat_as_floating_point_v<typename _Duration::rep>)
+ std::format_to(std::ostreambuf_iterator<_CharT>{__sstr},
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{:0{}.0f}"),
+ __value.subseconds().count(),
+ __value.fractional_width);
+ else
+ std::format_to(std::ostreambuf_iterator<_CharT>{__sstr},
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{:0{}}"),
+ __value.subseconds().count(),
+ __value.fractional_width);
+}
+
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB) && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && \
+ !defined(_LIBCPP_HAS_NO_FILESYSTEM) && !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+template <class _CharT, class _Duration, class _TimeZonePtr>
+_LIBCPP_HIDE_FROM_ABI void
+__format_sub_seconds(basic_stringstream<_CharT>& __sstr, const chrono::zoned_time<_Duration, _TimeZonePtr>& __value) {
+ __formatter::__format_sub_seconds(__sstr, __value.get_local_time().time_since_epoch());
+}
+# endif
+
+template <class _Tp>
+consteval bool __use_fraction() {
+ if constexpr (__is_time_point<_Tp>)
+ return chrono::hh_mm_ss<typename _Tp::duration>::fractional_width;
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB) && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && \
+ !defined(_LIBCPP_HAS_NO_FILESYSTEM) && !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ else if constexpr (__is_specialization_v<_Tp, chrono::zoned_time>)
+ return chrono::hh_mm_ss<typename _Tp::duration>::fractional_width;
+# endif
+ else if constexpr (chrono::__is_duration<_Tp>::value)
+ return chrono::hh_mm_ss<_Tp>::fractional_width;
+ else if constexpr (__is_hh_mm_ss<_Tp>)
+ return _Tp::fractional_width;
+ else
+ return false;
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI void __format_year(basic_stringstream<_CharT>& __sstr, int __year) {
+ if (__year < 0) {
+ __sstr << _CharT('-');
+ __year = -__year;
+ }
+
+ // TODO FMT Write an issue
+ // If the result has less than four digits it is zero-padded with 0 to two digits.
+ // is less -> has less
+ // left-padded -> zero-padded, otherwise the proper value would be 000-0.
+
+ // Note according to the wording it should be left padded, which is odd.
+ __sstr << std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:04}"), __year);
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI void __format_century(basic_stringstream<_CharT>& __sstr, int __year) {
+ // TODO FMT Write an issue
+ // [tab:time.format.spec]
+ // %C The year divided by 100 using floored division. If the result is a
+ // single decimal digit, it is prefixed with 0.
+
+ bool __negative = __year < 0;
+ int __century = (__year - (99 * __negative)) / 100; // floored division
+ __sstr << std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:02}"), __century);
+}
+
+// Implements the %z format specifier according to [tab:time.format.spec], where
+// '__modifier' signals %Oz or %Ez were used. (Both modifiers behave the same,
+// so there is no need to distinguish between them.)
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI void
+__format_zone_offset(basic_stringstream<_CharT>& __sstr, chrono::seconds __offset, bool __modifier) {
+ if (__offset < 0s) {
+ __sstr << _CharT('-');
+ __offset = -__offset;
+ } else {
+ __sstr << _CharT('+');
+ }
+
+ chrono::hh_mm_ss __hms{__offset};
+ std::ostreambuf_iterator<_CharT> __out_it{__sstr};
+ // Note HMS does not allow formatting hours > 23, but the offset is not limited to 24H.
+ std::format_to(__out_it, _LIBCPP_STATICALLY_WIDEN(_CharT, "{:02}"), __hms.hours().count());
+ if (__modifier)
+ __sstr << _CharT(':');
+ std::format_to(__out_it, _LIBCPP_STATICALLY_WIDEN(_CharT, "{:02}"), __hms.minutes().count());
+}
+
+// Helper to store the time zone information needed for formatting.
+struct _LIBCPP_HIDE_FROM_ABI __time_zone {
+ // Typically these abbreviations are short and fit in the string's internal
+ // buffer.
+ string __abbrev;
+ chrono::seconds __offset;
+};
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI __time_zone __convert_to_time_zone([[maybe_unused]] const _Tp& __value) {
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ if constexpr (same_as<_Tp, chrono::sys_info>)
+ return {__value.abbrev, __value.offset};
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ else if constexpr (__is_specialization_v<_Tp, chrono::zoned_time>)
+ return __formatter::__convert_to_time_zone(__value.get_info());
+# endif
+ else
+# endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ return {"UTC", chrono::seconds{0}};
+}
+
+template <class _CharT, class _Tp>
+_LIBCPP_HIDE_FROM_ABI void __format_chrono_using_chrono_specs(
+ basic_stringstream<_CharT>& __sstr, const _Tp& __value, basic_string_view<_CharT> __chrono_specs) {
+ tm __t = std::__convert_to_tm<tm>(__value);
+ __time_zone __z = __formatter::__convert_to_time_zone(__value);
+ const auto& __facet = std::use_facet<time_put<_CharT>>(__sstr.getloc());
+ for (auto __it = __chrono_specs.begin(); __it != __chrono_specs.end(); ++__it) {
+ if (*__it == _CharT('%')) {
+ auto __s = __it;
+ ++__it;
+ // We only handle the types that can't be directly handled by time_put.
+ // (as an optimization n, t, and % are also handled directly.)
+ switch (*__it) {
+ case _CharT('n'):
+ __sstr << _CharT('\n');
+ break;
+ case _CharT('t'):
+ __sstr << _CharT('\t');
+ break;
+ case _CharT('%'):
+ __sstr << *__it;
+ break;
+
+ case _CharT('C'): {
+ // strftime's output is only defined in the range [00, 99].
+ int __year = __t.tm_year + 1900;
+ if (__year < 1000 || __year > 9999)
+ __formatter::__format_century(__sstr, __year);
+ else
+ __facet.put(
+ {__sstr}, __sstr, _CharT(' '), std::addressof(__t), std::to_address(__s), std::to_address(__it + 1));
+ } break;
+
+ case _CharT('j'):
+ if constexpr (chrono::__is_duration<_Tp>::value)
+ // Converting a duration where the period has a small ratio to days
+ // may fail to compile. This due to loss of precision in the
+ // conversion. In order to avoid that issue convert to seconds as
+ // an intemediate step.
+ __sstr << chrono::duration_cast<chrono::days>(chrono::duration_cast<chrono::seconds>(__value)).count();
+ else
+ __facet.put(
+ {__sstr}, __sstr, _CharT(' '), std::addressof(__t), std::to_address(__s), std::to_address(__it + 1));
+ break;
+
+ case _CharT('q'):
+ if constexpr (chrono::__is_duration<_Tp>::value) {
+ __sstr << chrono::__units_suffix<_CharT, typename _Tp::period>();
+ break;
+ }
+ __builtin_unreachable();
+
+ case _CharT('Q'):
+ // TODO FMT Determine the proper ideas
+ // - Should it honour the precision?
+ // - Shoult it honour the locale setting for the separators?
+ // The wording for Q doesn't use the word locale and the effect of
+ // precision is unspecified.
+ //
+ // MSVC STL ignores precision but uses separator
+ // FMT honours precision and has a bug for separator
+ // https://godbolt.org/z/78b7sMxns
+ if constexpr (chrono::__is_duration<_Tp>::value) {
+ __sstr << std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{}"), __value.count());
+ break;
+ }
+ __builtin_unreachable();
+
+ case _CharT('S'):
+ case _CharT('T'):
+ __facet.put(
+ {__sstr}, __sstr, _CharT(' '), std::addressof(__t), std::to_address(__s), std::to_address(__it + 1));
+ if constexpr (__use_fraction<_Tp>())
+ __formatter::__format_sub_seconds(__sstr, __value);
+ break;
+
+ // Unlike time_put and strftime the formatting library requires %Y
+ //
+ // [tab:time.format.spec]
+ // The year as a decimal number. If the result is less than four digits
+ // it is left-padded with 0 to four digits.
+ //
+ // This means years in the range (-1000, 1000) need manual formatting.
+ // It's unclear whether %EY needs the same treatment. For example the
+ // Japanese EY contains the era name and year. This is zero-padded to 2
+ // digits in time_put (note that older glibc versions didn't do
+ // padding.) However most eras won't reach 100 years, let alone 1000.
+ // So padding to 4 digits seems unwanted for Japanese.
+ //
+ // The same applies to %Ex since that too depends on the era.
+ //
+ // %x the locale's date representation is currently doesn't handle the
+ // zero-padding too.
+ //
+ // The 4 digits can be implemented better at a later time. On POSIX
+ // systems the required information can be extracted by nl_langinfo
+ // https://man7.org/linux/man-pages/man3/nl_langinfo.3.html
+ //
+ // Note since year < -1000 is expected to be rare it uses the more
+ // expensive year routine.
+ //
+ // TODO FMT evaluate the comment above.
+
+# if defined(__GLIBC__) || defined(_AIX) || defined(_WIN32)
+ case _CharT('y'):
+ // Glibc fails for negative values, AIX for positive values too.
+ __sstr << std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:02}"), (std::abs(__t.tm_year + 1900)) % 100);
+ break;
+# endif // defined(__GLIBC__) || defined(_AIX) || defined(_WIN32)
+
+ case _CharT('Y'):
+ // Depending on the platform's libc the range of supported years is
+ // limited. Intead of of testing all conditions use the internal
+ // implementation unconditionally.
+ __formatter::__format_year(__sstr, __t.tm_year + 1900);
+ break;
+
+ case _CharT('F'):
+ // Depending on the platform's libc the range of supported years is
+ // limited. Instead of testing all conditions use the internal
+ // implementation unconditionally.
+ __formatter::__format_year(__sstr, __t.tm_year + 1900);
+ __sstr << std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "-{:02}-{:02}"), __t.tm_mon + 1, __t.tm_mday);
+ break;
+
+ case _CharT('z'):
+ __formatter::__format_zone_offset(__sstr, __z.__offset, false);
+ break;
+
+ case _CharT('Z'):
+ // __abbrev is always a char so the copy may convert.
+ ranges::copy(__z.__abbrev, std::ostreambuf_iterator<_CharT>{__sstr});
+ break;
+
+ case _CharT('O'):
+ if constexpr (__use_fraction<_Tp>()) {
+ // Handle OS using the normal representation for the non-fractional
+ // part. There seems to be no locale information regarding how the
+ // fractional part should be formatted.
+ if (*(__it + 1) == 'S') {
+ ++__it;
+ __facet.put(
+ {__sstr}, __sstr, _CharT(' '), std::addressof(__t), std::to_address(__s), std::to_address(__it + 1));
+ __formatter::__format_sub_seconds(__sstr, __value);
+ break;
+ }
+ }
+
+ // Oz produces the same output as Ez below.
+ [[fallthrough]];
+ case _CharT('E'):
+ ++__it;
+ if (*__it == 'z') {
+ __formatter::__format_zone_offset(__sstr, __z.__offset, true);
+ break;
+ }
+ [[fallthrough]];
+ default:
+ __facet.put(
+ {__sstr}, __sstr, _CharT(' '), std::addressof(__t), std::to_address(__s), std::to_address(__it + 1));
+ break;
+ }
+ } else {
+ __sstr << *__it;
+ }
+ }
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __weekday_ok(const _Tp& __value) {
+ if constexpr (__is_time_point<_Tp>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::day>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday_indexed>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday_last>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_day>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_day_last>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_weekday>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_weekday_last>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::year_month>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::year_month_day>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_day_last>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_weekday>)
+ return __value.weekday().ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_weekday_last>)
+ return __value.weekday().ok();
+ else if constexpr (__is_hh_mm_ss<_Tp>)
+ return true;
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ else if constexpr (same_as<_Tp, chrono::sys_info>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::local_info>)
+ return true;
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ else if constexpr (__is_specialization_v<_Tp, chrono::zoned_time>)
+ return true;
+# endif
+# endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ else
+ static_assert(sizeof(_Tp) == 0, "Add the missing type specialization");
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __weekday_name_ok(const _Tp& __value) {
+ if constexpr (__is_time_point<_Tp>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::day>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::weekday_indexed>)
+ return __value.weekday().ok();
+ else if constexpr (same_as<_Tp, chrono::weekday_last>)
+ return __value.weekday().ok();
+ else if constexpr (same_as<_Tp, chrono::month_day>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_day_last>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_weekday>)
+ return __value.weekday_indexed().ok();
+ else if constexpr (same_as<_Tp, chrono::month_weekday_last>)
+ return __value.weekday_indexed().ok();
+ else if constexpr (same_as<_Tp, chrono::year_month>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::year_month_day>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_day_last>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_weekday>)
+ return __value.weekday().ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_weekday_last>)
+ return __value.weekday().ok();
+ else if constexpr (__is_hh_mm_ss<_Tp>)
+ return true;
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ else if constexpr (same_as<_Tp, chrono::sys_info>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::local_info>)
+ return true;
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ else if constexpr (__is_specialization_v<_Tp, chrono::zoned_time>)
+ return true;
+# endif
+# endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ else
+ static_assert(sizeof(_Tp) == 0, "Add the missing type specialization");
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __date_ok(const _Tp& __value) {
+ if constexpr (__is_time_point<_Tp>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::day>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday_indexed>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday_last>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_day>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_day_last>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_weekday>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_weekday_last>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::year_month>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::year_month_day>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_day_last>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_weekday>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_weekday_last>)
+ return __value.ok();
+ else if constexpr (__is_hh_mm_ss<_Tp>)
+ return true;
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ else if constexpr (same_as<_Tp, chrono::sys_info>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::local_info>)
+ return true;
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ else if constexpr (__is_specialization_v<_Tp, chrono::zoned_time>)
+ return true;
+# endif
+# endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ else
+ static_assert(sizeof(_Tp) == 0, "Add the missing type specialization");
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __month_name_ok(const _Tp& __value) {
+ if constexpr (__is_time_point<_Tp>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::day>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month>)
+ return __value.ok();
+ else if constexpr (same_as<_Tp, chrono::year>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday_indexed>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::weekday_last>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::month_day>)
+ return __value.month().ok();
+ else if constexpr (same_as<_Tp, chrono::month_day_last>)
+ return __value.month().ok();
+ else if constexpr (same_as<_Tp, chrono::month_weekday>)
+ return __value.month().ok();
+ else if constexpr (same_as<_Tp, chrono::month_weekday_last>)
+ return __value.month().ok();
+ else if constexpr (same_as<_Tp, chrono::year_month>)
+ return __value.month().ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_day>)
+ return __value.month().ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_day_last>)
+ return __value.month().ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_weekday>)
+ return __value.month().ok();
+ else if constexpr (same_as<_Tp, chrono::year_month_weekday_last>)
+ return __value.month().ok();
+ else if constexpr (__is_hh_mm_ss<_Tp>)
+ return true;
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ else if constexpr (same_as<_Tp, chrono::sys_info>)
+ return true;
+ else if constexpr (same_as<_Tp, chrono::local_info>)
+ return true;
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ else if constexpr (__is_specialization_v<_Tp, chrono::zoned_time>)
+ return true;
+# endif
+# endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+ else
+ static_assert(sizeof(_Tp) == 0, "Add the missing type specialization");
+}
+
+template <class _CharT, class _Tp, class _FormatContext>
+_LIBCPP_HIDE_FROM_ABI auto
+__format_chrono(const _Tp& __value,
+ _FormatContext& __ctx,
+ __format_spec::__parsed_specifications<_CharT> __specs,
+ basic_string_view<_CharT> __chrono_specs) {
+ basic_stringstream<_CharT> __sstr;
+ // [time.format]/2
+ // 2.1 - the "C" locale if the L option is not present in chrono-format-spec, otherwise
+ // 2.2 - the locale passed to the formatting function if any, otherwise
+ // 2.3 - the global locale.
+ // Note that the __ctx's locale() call does 2.2 and 2.3.
+ if (__specs.__chrono_.__locale_specific_form_)
+ __sstr.imbue(__ctx.locale());
+ else
+ __sstr.imbue(locale::classic());
+
+ if (__chrono_specs.empty())
+ __sstr << __value;
+ else {
+ if constexpr (chrono::__is_duration<_Tp>::value) {
+ // A duration can be a user defined arithmetic type. Users may specialize
+ // numeric_limits, but they may not specialize is_signed.
+ if constexpr (numeric_limits<typename _Tp::rep>::is_signed) {
+ if (__value < __value.zero()) {
+ __sstr << _CharT('-');
+ __formatter::__format_chrono_using_chrono_specs(__sstr, -__value, __chrono_specs);
+ } else
+ __formatter::__format_chrono_using_chrono_specs(__sstr, __value, __chrono_specs);
+ } else
+ __formatter::__format_chrono_using_chrono_specs(__sstr, __value, __chrono_specs);
+ // TODO FMT When keeping the precision it will truncate the string.
+ // Note that the behaviour what the precision does isn't specified.
+ __specs.__precision_ = -1;
+ } else {
+ // Test __weekday_name_ before __weekday_ to give a better error.
+ if (__specs.__chrono_.__weekday_name_ && !__formatter::__weekday_name_ok(__value))
+ std::__throw_format_error("Formatting a weekday name needs a valid weekday");
+
+ if (__specs.__chrono_.__weekday_ && !__formatter::__weekday_ok(__value))
+ std::__throw_format_error("Formatting a weekday needs a valid weekday");
+
+ if (__specs.__chrono_.__day_of_year_ && !__formatter::__date_ok(__value))
+ std::__throw_format_error("Formatting a day of year needs a valid date");
+
+ if (__specs.__chrono_.__week_of_year_ && !__formatter::__date_ok(__value))
+ std::__throw_format_error("Formatting a week of year needs a valid date");
+
+ if (__specs.__chrono_.__month_name_ && !__formatter::__month_name_ok(__value))
+ std::__throw_format_error("Formatting a month name from an invalid month number");
+
+ if constexpr (__is_hh_mm_ss<_Tp>) {
+ // Note this is a pedantic intepretation of the Standard. A hh_mm_ss
+ // is no longer a time_of_day and can store an arbitrary number of
+ // hours. A number of hours in a 12 or 24 hour clock can't represent
+ // 24 hours or more. The functions std::chrono::make12 and
+ // std::chrono::make24 reaffirm this view point.
+ //
+ // Interestingly this will be the only output stream function that
+ // throws.
+ //
+ // TODO FMT The wording probably needs to be adapted to
+ // - The displayed hours is hh_mm_ss.hours() % 24
+ // - It should probably allow %j in the same fashion as duration.
+ // - The stream formatter should change its output when hours >= 24
+ // - Write it as not valid,
+ // - or write the number of days.
+ if (__specs.__chrono_.__hour_ && __value.hours().count() > 23)
+ std::__throw_format_error("Formatting a hour needs a valid value");
+
+ if (__value.is_negative())
+ __sstr << _CharT('-');
+ }
+
+ __formatter::__format_chrono_using_chrono_specs(__sstr, __value, __chrono_specs);
+ }
+ }
+
+ return __formatter::__write_string(__sstr.view(), __ctx.out(), __specs);
+}
+
+} // namespace __formatter
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS __formatter_chrono {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator
+ __parse(_ParseContext& __ctx, __format_spec::__fields __fields, __format_spec::__flags __flags) {
+ return __parser_.__parse(__ctx, __fields, __flags);
+ }
+
+ template <class _Tp, class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(const _Tp& __value, _FormatContext& __ctx) const {
+ return __formatter::__format_chrono(
+ __value, __ctx, __parser_.__parser_.__get_parsed_chrono_specifications(__ctx), __parser_.__chrono_specs_);
+ }
+
+ __format_spec::__parser_chrono<_CharT> __parser_;
+};
+
+template <class _Duration, __fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::sys_time<_Duration>, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__clock);
+ }
+};
+
+template <class _Duration, __fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::file_time<_Duration>, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__clock);
+ }
+};
+
+template <class _Duration, __fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::local_time<_Duration>, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ // The flags are not __clock since there is no associated time-zone.
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__date_time);
+ }
+};
+
+template <class _Rep, class _Period, __fmt_char_type _CharT>
+struct formatter<chrono::duration<_Rep, _Period>, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ // [time.format]/1
+ // Giving a precision specification in the chrono-format-spec is valid only
+ // for std::chrono::duration types where the representation type Rep is a
+ // floating-point type. For all other Rep types, an exception of type
+ // format_error is thrown if the chrono-format-spec contains a precision
+ // specification.
+ //
+ // Note this doesn't refer to chrono::treat_as_floating_point_v<_Rep>.
+ if constexpr (std::floating_point<_Rep>)
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono_fractional, __format_spec::__flags::__duration);
+ else
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__duration);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::day, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__day);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::month, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__month);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::year, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__year);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::weekday, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__weekday);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::weekday_indexed, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__weekday);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::weekday_last, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__weekday);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::month_day, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__month_day);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::month_day_last, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__month);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::month_weekday, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__month_weekday);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::month_weekday_last, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__month_weekday);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::year_month, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__year_month);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::year_month_day, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__date);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::year_month_day_last, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__date);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::year_month_weekday, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__date);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<chrono::year_month_weekday_last, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__date);
+ }
+};
+
+template <class _Duration, __fmt_char_type _CharT>
+struct formatter<chrono::hh_mm_ss<_Duration>, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__time);
+ }
+};
+
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+template <__fmt_char_type _CharT>
+struct formatter<chrono::sys_info, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__time_zone);
+ }
+};
+
+template <__fmt_char_type _CharT>
+struct formatter<chrono::local_info, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags{});
+ }
+};
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+// Note due to how libc++'s formatters are implemented there is no need to add
+// the exposition only local-time-format-t abstraction.
+template <class _Duration, class _TimeZonePtr, __fmt_char_type _CharT>
+struct formatter<chrono::zoned_time<_Duration, _TimeZonePtr>, _CharT> : public __formatter_chrono<_CharT> {
+public:
+ using _Base = __formatter_chrono<_CharT>;
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return _Base::__parse(__ctx, __format_spec::__fields_chrono, __format_spec::__flags::__clock);
+ }
+};
+# endif // !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) &&
+ // !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHRONO_FORMATTER_H
diff --git a/libcxx/include/__cxx03/__chrono/hh_mm_ss.h b/libcxx/include/__cxx03/__chrono/hh_mm_ss.h
new file mode 100644
index 00000000000000..57d2247fe6a3c8
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/hh_mm_ss.h
@@ -0,0 +1,112 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_HH_MM_SS_H
+#define _LIBCPP___CHRONO_HH_MM_SS_H
+
+#include <__chrono/duration.h>
+#include <__chrono/time_point.h>
+#include <__config>
+#include <__type_traits/common_type.h>
+#include <ratio>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+template <class _Duration>
+class hh_mm_ss {
+private:
+ static_assert(__is_duration<_Duration>::value, "template parameter of hh_mm_ss must be a std::chrono::duration");
+ using __CommonType = common_type_t<_Duration, chrono::seconds>;
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr uint64_t __pow10(unsigned __exp) {
+ uint64_t __ret = 1;
+ for (unsigned __i = 0; __i < __exp; ++__i)
+ __ret *= 10U;
+ return __ret;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr unsigned __width(uint64_t __n, uint64_t __d = 10, unsigned __w = 0) {
+ if (__n >= 2 && __d != 0 && __w < 19)
+ return 1 + __width(__n, __d % __n * 10, __w + 1);
+ return 0;
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI static unsigned constexpr fractional_width =
+ __width(__CommonType::period::den) < 19 ? __width(__CommonType::period::den) : 6u;
+ using precision = duration<typename __CommonType::rep, ratio<1, __pow10(fractional_width)>>;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr hh_mm_ss() noexcept : hh_mm_ss{_Duration::zero()} {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit hh_mm_ss(_Duration __d) noexcept
+ : __is_neg_(__d < _Duration(0)),
+ __h_(chrono::duration_cast<chrono::hours>(chrono::abs(__d))),
+ __m_(chrono::duration_cast<chrono::minutes>(chrono::abs(__d) - hours())),
+ __s_(chrono::duration_cast<chrono::seconds>(chrono::abs(__d) - hours() - minutes())),
+ __f_(chrono::duration_cast<precision>(chrono::abs(__d) - hours() - minutes() - seconds())) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool is_negative() const noexcept { return __is_neg_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr chrono::hours hours() const noexcept { return __h_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr chrono::minutes minutes() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr chrono::seconds seconds() const noexcept { return __s_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr precision subseconds() const noexcept { return __f_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr precision to_duration() const noexcept {
+ auto __dur = __h_ + __m_ + __s_ + __f_;
+ return __is_neg_ ? -__dur : __dur;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator precision() const noexcept { return to_duration(); }
+
+private:
+ bool __is_neg_;
+ chrono::hours __h_;
+ chrono::minutes __m_;
+ chrono::seconds __s_;
+ precision __f_;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(hh_mm_ss);
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_am(const hours& __h) noexcept {
+ return __h >= hours(0) && __h < hours(12);
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_pm(const hours& __h) noexcept {
+ return __h >= hours(12) && __h < hours(24);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr hours make12(const hours& __h) noexcept {
+ if (__h == hours(0))
+ return hours(12);
+ else if (__h <= hours(12))
+ return __h;
+ else
+ return __h - hours(12);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr hours make24(const hours& __h, bool __is_pm) noexcept {
+ if (__is_pm)
+ return __h == hours(12) ? __h : __h + hours(12);
+ else
+ return __h == hours(12) ? hours(0) : __h;
+}
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_HH_MM_SS_H
diff --git a/libcxx/include/__cxx03/__chrono/high_resolution_clock.h b/libcxx/include/__cxx03/__chrono/high_resolution_clock.h
new file mode 100644
index 00000000000000..0697fd2de9b4de
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/high_resolution_clock.h
@@ -0,0 +1,35 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_HIGH_RESOLUTION_CLOCK_H
+#define _LIBCPP___CHRONO_HIGH_RESOLUTION_CLOCK_H
+
+#include <__chrono/steady_clock.h>
+#include <__chrono/system_clock.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+#ifndef _LIBCPP_HAS_NO_MONOTONIC_CLOCK
+typedef steady_clock high_resolution_clock;
+#else
+typedef system_clock high_resolution_clock;
+#endif
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHRONO_HIGH_RESOLUTION_CLOCK_H
diff --git a/libcxx/include/__cxx03/__chrono/leap_second.h b/libcxx/include/__cxx03/__chrono/leap_second.h
new file mode 100644
index 00000000000000..1a0e7f3107de81
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/leap_second.h
@@ -0,0 +1,126 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_LEAP_SECOND_H
+#define _LIBCPP___CHRONO_LEAP_SECOND_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__chrono/duration.h>
+# include <__chrono/system_clock.h>
+# include <__chrono/time_point.h>
+# include <__compare/ordering.h>
+# include <__compare/three_way_comparable.h>
+# include <__config>
+# include <__utility/private_constructor_tag.h>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20
+
+namespace chrono {
+
+class leap_second {
+public:
+ [[nodiscard]]
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr leap_second(__private_constructor_tag, sys_seconds __date, seconds __value)
+ : __date_(__date), __value_(__value) {}
+
+ _LIBCPP_HIDE_FROM_ABI leap_second(const leap_second&) = default;
+ _LIBCPP_HIDE_FROM_ABI leap_second& operator=(const leap_second&) = default;
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI constexpr sys_seconds date() const noexcept { return __date_; }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI constexpr seconds value() const noexcept { return __value_; }
+
+private:
+ sys_seconds __date_;
+ seconds __value_;
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(const leap_second& __x, const leap_second& __y) {
+ return __x.date() == __y.date();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering operator<=>(const leap_second& __x, const leap_second& __y) {
+ return __x.date() <=> __y.date();
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(const leap_second& __x, const sys_time<_Duration>& __y) {
+ return __x.date() == __y;
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<(const leap_second& __x, const sys_time<_Duration>& __y) {
+ return __x.date() < __y;
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<(const sys_time<_Duration>& __x, const leap_second& __y) {
+ return __x < __y.date();
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>(const leap_second& __x, const sys_time<_Duration>& __y) {
+ return __y < __x;
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>(const sys_time<_Duration>& __x, const leap_second& __y) {
+ return __y < __x;
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(const leap_second& __x, const sys_time<_Duration>& __y) {
+ return !(__y < __x);
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(const sys_time<_Duration>& __x, const leap_second& __y) {
+ return !(__y < __x);
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(const leap_second& __x, const sys_time<_Duration>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Duration>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(const sys_time<_Duration>& __x, const leap_second& __y) {
+ return !(__x < __y);
+}
+
+# ifndef _LIBCPP_COMPILER_GCC
+// This requirement cause a compilation loop in GCC-13 and running out of memory.
+// TODO TZDB Test whether GCC-14 fixes this.
+template <class _Duration>
+ requires three_way_comparable_with<sys_seconds, sys_time<_Duration>>
+_LIBCPP_HIDE_FROM_ABI constexpr auto operator<=>(const leap_second& __x, const sys_time<_Duration>& __y) {
+ return __x.date() <=> __y;
+}
+# endif
+
+} // namespace chrono
+
+# endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_LEAP_SECOND_H
diff --git a/libcxx/include/__cxx03/__chrono/literals.h b/libcxx/include/__cxx03/__chrono/literals.h
new file mode 100644
index 00000000000000..89800440edf435
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/literals.h
@@ -0,0 +1,45 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_LITERALS_H
+#define _LIBCPP___CHRONO_LITERALS_H
+
+#include <__chrono/day.h>
+#include <__chrono/year.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+inline namespace literals {
+inline namespace chrono_literals {
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::day operator""d(unsigned long long __d) noexcept {
+ return chrono::day(static_cast<unsigned>(__d));
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr chrono::year operator""y(unsigned long long __y) noexcept {
+ return chrono::year(static_cast<int>(__y));
+}
+} // namespace chrono_literals
+} // namespace literals
+
+namespace chrono { // hoist the literals into namespace std::chrono
+using namespace literals::chrono_literals;
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_LITERALS_H
diff --git a/libcxx/include/__cxx03/__chrono/local_info.h b/libcxx/include/__cxx03/__chrono/local_info.h
new file mode 100644
index 00000000000000..cfe1448904d3f7
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/local_info.h
@@ -0,0 +1,50 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_LOCAL_INFO_H
+#define _LIBCPP___CHRONO_LOCAL_INFO_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__chrono/sys_info.h>
+# include <__config>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20
+
+namespace chrono {
+
+struct local_info {
+ static constexpr int unique = 0;
+ static constexpr int nonexistent = 1;
+ static constexpr int ambiguous = 2;
+
+ int result;
+ sys_info first;
+ sys_info second;
+};
+
+} // namespace chrono
+
+# endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_LOCAL_INFO_H
diff --git a/libcxx/include/__cxx03/__chrono/month.h b/libcxx/include/__cxx03/__chrono/month.h
new file mode 100644
index 00000000000000..ce5cc21aab7d1e
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/month.h
@@ -0,0 +1,115 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_MONTH_H
+#define _LIBCPP___CHRONO_MONTH_H
+
+#include <__chrono/duration.h>
+#include <__config>
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class month {
+private:
+ unsigned char __m_;
+
+public:
+ month() = default;
+ _LIBCPP_HIDE_FROM_ABI explicit inline constexpr month(unsigned __val) noexcept
+ : __m_(static_cast<unsigned char>(__val)) {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr month& operator++() noexcept {
+ *this += months{1};
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr month operator++(int) noexcept {
+ month __tmp = *this;
+ ++(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr month& operator--() noexcept {
+ *this -= months{1};
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr month operator--(int) noexcept {
+ month __tmp = *this;
+ --(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr month& operator+=(const months& __m1) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr month& operator-=(const months& __m1) noexcept;
+ _LIBCPP_HIDE_FROM_ABI explicit inline constexpr operator unsigned() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __m_ >= 1 && __m_ <= 12; }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(const month& __lhs, const month& __rhs) noexcept {
+ return static_cast<unsigned>(__lhs) == static_cast<unsigned>(__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering operator<=>(const month& __lhs, const month& __rhs) noexcept {
+ return static_cast<unsigned>(__lhs) <=> static_cast<unsigned>(__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month operator+(const month& __lhs, const months& __rhs) noexcept {
+ auto const __mu = static_cast<long long>(static_cast<unsigned>(__lhs)) + (__rhs.count() - 1);
+ auto const __yr = (__mu >= 0 ? __mu : __mu - 11) / 12;
+ return month{static_cast<unsigned>(__mu - __yr * 12 + 1)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month operator+(const months& __lhs, const month& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month operator-(const month& __lhs, const months& __rhs) noexcept {
+ return __lhs + -__rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr months operator-(const month& __lhs, const month& __rhs) noexcept {
+ auto const __dm = static_cast<unsigned>(__lhs) - static_cast<unsigned>(__rhs);
+ return months(__dm <= 11 ? __dm : __dm + 12);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month& month::operator+=(const months& __dm) noexcept {
+ *this = *this + __dm;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month& month::operator-=(const months& __dm) noexcept {
+ *this = *this - __dm;
+ return *this;
+}
+
+inline constexpr month January{1};
+inline constexpr month February{2};
+inline constexpr month March{3};
+inline constexpr month April{4};
+inline constexpr month May{5};
+inline constexpr month June{6};
+inline constexpr month July{7};
+inline constexpr month August{8};
+inline constexpr month September{9};
+inline constexpr month October{10};
+inline constexpr month November{11};
+inline constexpr month December{12};
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_MONTH_H
diff --git a/libcxx/include/__cxx03/__chrono/month_weekday.h b/libcxx/include/__cxx03/__chrono/month_weekday.h
new file mode 100644
index 00000000000000..79198796552148
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/month_weekday.h
@@ -0,0 +1,105 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_MONTH_WEEKDAY_H
+#define _LIBCPP___CHRONO_MONTH_WEEKDAY_H
+
+#include <__chrono/month.h>
+#include <__chrono/weekday.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class month_weekday {
+private:
+ chrono::month __m_;
+ chrono::weekday_indexed __wdi_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr month_weekday(const chrono::month& __mval,
+ const chrono::weekday_indexed& __wdival) noexcept
+ : __m_{__mval}, __wdi_{__wdival} {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::weekday_indexed weekday_indexed() const noexcept { return __wdi_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __m_.ok() && __wdi_.ok(); }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool
+operator==(const month_weekday& __lhs, const month_weekday& __rhs) noexcept {
+ return __lhs.month() == __rhs.month() && __lhs.weekday_indexed() == __rhs.weekday_indexed();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_weekday
+operator/(const month& __lhs, const weekday_indexed& __rhs) noexcept {
+ return month_weekday{__lhs, __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_weekday operator/(int __lhs, const weekday_indexed& __rhs) noexcept {
+ return month_weekday{month(__lhs), __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_weekday
+operator/(const weekday_indexed& __lhs, const month& __rhs) noexcept {
+ return month_weekday{__rhs, __lhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_weekday operator/(const weekday_indexed& __lhs, int __rhs) noexcept {
+ return month_weekday{month(__rhs), __lhs};
+}
+
+class month_weekday_last {
+ chrono::month __m_;
+ chrono::weekday_last __wdl_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr month_weekday_last(const chrono::month& __mval,
+ const chrono::weekday_last& __wdlval) noexcept
+ : __m_{__mval}, __wdl_{__wdlval} {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::weekday_last weekday_last() const noexcept { return __wdl_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __m_.ok() && __wdl_.ok(); }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool
+operator==(const month_weekday_last& __lhs, const month_weekday_last& __rhs) noexcept {
+ return __lhs.month() == __rhs.month() && __lhs.weekday_last() == __rhs.weekday_last();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_weekday_last
+operator/(const month& __lhs, const weekday_last& __rhs) noexcept {
+ return month_weekday_last{__lhs, __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_weekday_last operator/(int __lhs, const weekday_last& __rhs) noexcept {
+ return month_weekday_last{month(__lhs), __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_weekday_last
+operator/(const weekday_last& __lhs, const month& __rhs) noexcept {
+ return month_weekday_last{__rhs, __lhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_weekday_last operator/(const weekday_last& __lhs, int __rhs) noexcept {
+ return month_weekday_last{month(__rhs), __lhs};
+}
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_MONTH_WEEKDAY_H
diff --git a/libcxx/include/__cxx03/__chrono/monthday.h b/libcxx/include/__cxx03/__chrono/monthday.h
new file mode 100644
index 00000000000000..a89d16e518618e
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/monthday.h
@@ -0,0 +1,133 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_MONTHDAY_H
+#define _LIBCPP___CHRONO_MONTHDAY_H
+
+#include <__chrono/calendar.h>
+#include <__chrono/day.h>
+#include <__chrono/month.h>
+#include <__config>
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class month_day {
+private:
+ chrono::month __m_;
+ chrono::day __d_;
+
+public:
+ month_day() = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr month_day(const chrono::month& __mval, const chrono::day& __dval) noexcept
+ : __m_{__mval}, __d_{__dval} {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::day day() const noexcept { return __d_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr bool ok() const noexcept;
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool month_day::ok() const noexcept {
+ if (!__m_.ok())
+ return false;
+ const unsigned __dval = static_cast<unsigned>(__d_);
+ if (__dval < 1 || __dval > 31)
+ return false;
+ if (__dval <= 29)
+ return true;
+ // Now we've got either 30 or 31
+ const unsigned __mval = static_cast<unsigned>(__m_);
+ if (__mval == 2)
+ return false;
+ if (__mval == 4 || __mval == 6 || __mval == 9 || __mval == 11)
+ return __dval == 30;
+ return true;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(const month_day& __lhs, const month_day& __rhs) noexcept {
+ return __lhs.month() == __rhs.month() && __lhs.day() == __rhs.day();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering
+operator<=>(const month_day& __lhs, const month_day& __rhs) noexcept {
+ if (auto __c = __lhs.month() <=> __rhs.month(); __c != 0)
+ return __c;
+ return __lhs.day() <=> __rhs.day();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day operator/(const month& __lhs, const day& __rhs) noexcept {
+ return month_day{__lhs, __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day operator/(const day& __lhs, const month& __rhs) noexcept {
+ return __rhs / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day operator/(const month& __lhs, int __rhs) noexcept {
+ return __lhs / day(__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day operator/(int __lhs, const day& __rhs) noexcept {
+ return month(__lhs) / __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day operator/(const day& __lhs, int __rhs) noexcept {
+ return month(__rhs) / __lhs;
+}
+
+class month_day_last {
+private:
+ chrono::month __m_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr month_day_last(const chrono::month& __val) noexcept : __m_{__val} {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __m_.ok(); }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool
+operator==(const month_day_last& __lhs, const month_day_last& __rhs) noexcept {
+ return __lhs.month() == __rhs.month();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering
+operator<=>(const month_day_last& __lhs, const month_day_last& __rhs) noexcept {
+ return __lhs.month() <=> __rhs.month();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day_last operator/(const month& __lhs, last_spec) noexcept {
+ return month_day_last{__lhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day_last operator/(last_spec, const month& __rhs) noexcept {
+ return month_day_last{__rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day_last operator/(int __lhs, last_spec) noexcept {
+ return month_day_last{month(__lhs)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr month_day_last operator/(last_spec, int __rhs) noexcept {
+ return month_day_last{month(__rhs)};
+}
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_MONTHDAY_H
diff --git a/libcxx/include/__cxx03/__chrono/ostream.h b/libcxx/include/__cxx03/__chrono/ostream.h
new file mode 100644
index 00000000000000..e6c43254eea15e
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/ostream.h
@@ -0,0 +1,322 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_OSTREAM_H
+#define _LIBCPP___CHRONO_OSTREAM_H
+
+#include <__chrono/calendar.h>
+#include <__chrono/day.h>
+#include <__chrono/duration.h>
+#include <__chrono/file_clock.h>
+#include <__chrono/hh_mm_ss.h>
+#include <__chrono/local_info.h>
+#include <__chrono/month.h>
+#include <__chrono/month_weekday.h>
+#include <__chrono/monthday.h>
+#include <__chrono/statically_widen.h>
+#include <__chrono/sys_info.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/weekday.h>
+#include <__chrono/year.h>
+#include <__chrono/year_month.h>
+#include <__chrono/year_month_day.h>
+#include <__chrono/year_month_weekday.h>
+#include <__chrono/zoned_time.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/format_functions.h>
+#include <__fwd/ostream.h>
+#include <ratio>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace chrono {
+
+template <class _CharT, class _Traits, class _Duration>
+ requires(!treat_as_floating_point_v<typename _Duration::rep> && _Duration{1} < days{1})
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const sys_time<_Duration>& __tp) {
+ return __os << std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L%F %T}"), __tp);
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const sys_days& __dp) {
+ return __os << year_month_day{__dp};
+}
+
+template <class _CharT, class _Traits, class _Duration>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const file_time<_Duration> __tp) {
+ return __os << std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L%F %T}"), __tp);
+}
+
+template <class _CharT, class _Traits, class _Duration>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const local_time<_Duration> __tp) {
+ return __os << sys_time<_Duration>{__tp.time_since_epoch()};
+}
+
+// Depending on the type the return is a const _CharT* or a basic_string<_CharT>
+template <class _CharT, class _Period>
+_LIBCPP_HIDE_FROM_ABI auto __units_suffix() {
+ // TODO FMT LWG issue the suffixes are always char and not STATICALLY-WIDEN'ed.
+ if constexpr (same_as<typename _Period::type, atto>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "as");
+ else if constexpr (same_as<typename _Period::type, femto>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "fs");
+ else if constexpr (same_as<typename _Period::type, pico>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "ps");
+ else if constexpr (same_as<typename _Period::type, nano>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "ns");
+ else if constexpr (same_as<typename _Period::type, micro>)
+# ifndef _LIBCPP_HAS_NO_UNICODE
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "\u00b5s");
+# else
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "us");
+# endif
+ else if constexpr (same_as<typename _Period::type, milli>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "ms");
+ else if constexpr (same_as<typename _Period::type, centi>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "cs");
+ else if constexpr (same_as<typename _Period::type, deci>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "ds");
+ else if constexpr (same_as<typename _Period::type, ratio<1>>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "s");
+ else if constexpr (same_as<typename _Period::type, deca>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "das");
+ else if constexpr (same_as<typename _Period::type, hecto>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "hs");
+ else if constexpr (same_as<typename _Period::type, kilo>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "ks");
+ else if constexpr (same_as<typename _Period::type, mega>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "Ms");
+ else if constexpr (same_as<typename _Period::type, giga>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "Gs");
+ else if constexpr (same_as<typename _Period::type, tera>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "Ts");
+ else if constexpr (same_as<typename _Period::type, peta>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "Ps");
+ else if constexpr (same_as<typename _Period::type, exa>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "Es");
+ else if constexpr (same_as<typename _Period::type, ratio<60>>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "min");
+ else if constexpr (same_as<typename _Period::type, ratio<3600>>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "h");
+ else if constexpr (same_as<typename _Period::type, ratio<86400>>)
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "d");
+ else if constexpr (_Period::den == 1)
+ return std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "[{}]s"), _Period::num);
+ else
+ return std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "[{}/{}]s"), _Period::num, _Period::den);
+}
+
+template <class _CharT, class _Traits, class _Rep, class _Period>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const duration<_Rep, _Period>& __d) {
+ basic_ostringstream<_CharT, _Traits> __s;
+ __s.flags(__os.flags());
+ __s.imbue(__os.getloc());
+ __s.precision(__os.precision());
+ __s << __d.count() << chrono::__units_suffix<_CharT, _Period>();
+ return __os << __s.str();
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& __os, const day& __d) {
+ return __os << (__d.ok() ? std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:%d}"), __d)
+ // Note this error differs from the wording of the Standard. The
+ // Standard wording doesn't work well on AIX or Windows. There
+ // the formatted day seems to be either modulo 100 or completely
+ // omitted. Judging by the wording this is valid.
+ // TODO FMT Write a paper of file an LWG issue.
+ : std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:02} is not a valid day"),
+ static_cast<unsigned>(__d)));
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const month& __m) {
+ return __os << (__m.ok() ? std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L%b}"), __m)
+ : std::format(__os.getloc(),
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{} is not a valid month"),
+ static_cast<unsigned>(__m))); // TODO FMT Standard mandated locale isn't used.
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const year& __y) {
+ return __os << (__y.ok() ? std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:%Y}"), __y)
+ : std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:%Y} is not a valid year"), __y));
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const weekday& __wd) {
+ return __os << (__wd.ok() ? std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L%a}"), __wd)
+ : std::format(__os.getloc(), // TODO FMT Standard mandated locale isn't used.
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{} is not a valid weekday"),
+ static_cast<unsigned>(__wd.c_encoding())));
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const weekday_indexed& __wdi) {
+ auto __i = __wdi.index();
+ return __os << (__i >= 1 && __i <= 5
+ ? std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L}[{}]"), __wdi.weekday(), __i)
+ : std::format(__os.getloc(),
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L}[{} is not a valid index]"),
+ __wdi.weekday(),
+ __i));
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const weekday_last& __wdl) {
+ return __os << std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L}[last]"), __wdl.weekday());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const month_day& __md) {
+ // TODO FMT The Standard allows 30th of February to be printed.
+ // It would be nice to show an error message instead.
+ return __os << std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L}/{}"), __md.month(), __md.day());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const month_day_last& __mdl) {
+ return __os << std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L}/last"), __mdl.month());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const month_weekday& __mwd) {
+ return __os << std::format(
+ __os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L}/{:L}"), __mwd.month(), __mwd.weekday_indexed());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const month_weekday_last& __mwdl) {
+ return __os << std::format(
+ __os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L}/{:L}"), __mwdl.month(), __mwdl.weekday_last());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const year_month& __ym) {
+ return __os << std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{}/{:L}"), __ym.year(), __ym.month());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const year_month_day& __ymd) {
+ return __os << (__ymd.ok() ? std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:%F}"), __ymd)
+ : std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "{:%F} is not a valid date"), __ymd));
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const year_month_day_last& __ymdl) {
+ return __os << std::format(
+ __os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{}/{:L}"), __ymdl.year(), __ymdl.month_day_last());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const year_month_weekday& __ymwd) {
+ return __os << std::format(
+ __os.getloc(),
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{}/{:L}/{:L}"),
+ __ymwd.year(),
+ __ymwd.month(),
+ __ymwd.weekday_indexed());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const year_month_weekday_last& __ymwdl) {
+ return __os << std::format(
+ __os.getloc(),
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{}/{:L}/{:L}"),
+ __ymwdl.year(),
+ __ymwdl.month(),
+ __ymwdl.weekday_last());
+}
+
+template <class _CharT, class _Traits, class _Duration>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const hh_mm_ss<_Duration> __hms) {
+ return __os << std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L%T}"), __hms);
+}
+
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const sys_info& __info) {
+ // __info.abbrev is always std::basic_string<char>.
+ // Since these strings typically are short the conversion should be cheap.
+ std::basic_string<_CharT> __abbrev{__info.abbrev.begin(), __info.abbrev.end()};
+ return __os << std::format(
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "[{:%F %T}, {:%F %T}) {:%T} {:%Q%q} \"{}\""),
+ __info.begin,
+ __info.end,
+ hh_mm_ss{__info.offset},
+ __info.save,
+ __abbrev);
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const local_info& __info) {
+ auto __result = [&]() -> basic_string<_CharT> {
+ switch (__info.result) {
+ case local_info::unique:
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "unique");
+ case local_info::nonexistent:
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "non-existent");
+ case local_info::ambiguous:
+ return _LIBCPP_STATICALLY_WIDEN(_CharT, "ambiguous");
+
+ default:
+ return std::format(_LIBCPP_STATICALLY_WIDEN(_CharT, "unspecified result ({})"), __info.result);
+ };
+ };
+
+ return __os << std::format(
+ _LIBCPP_STATICALLY_WIDEN(_CharT, "{}: {{{}, {}}}"), __result(), __info.first, __info.second);
+}
+
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+template <class _CharT, class _Traits, class _Duration, class _TimeZonePtr>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const zoned_time<_Duration, _TimeZonePtr>& __tp) {
+ return __os << std::format(__os.getloc(), _LIBCPP_STATICALLY_WIDEN(_CharT, "{:L%F %T %Z}"), __tp);
+}
+# endif
+# endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+} // namespace chrono
+
+#endif // if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHRONO_OSTREAM_H
diff --git a/libcxx/include/__cxx03/__chrono/parser_std_format_spec.h b/libcxx/include/__cxx03/__chrono/parser_std_format_spec.h
new file mode 100644
index 00000000000000..785bbae198e464
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/parser_std_format_spec.h
@@ -0,0 +1,416 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_PARSER_STD_FORMAT_SPEC_H
+#define _LIBCPP___CHRONO_PARSER_STD_FORMAT_SPEC_H
+
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_error.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter_string.h>
+#include <__format/parser_std_format_spec.h>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __format_spec {
+
+// By not placing this constant in the formatter class it's not duplicated for char and wchar_t
+inline constexpr __fields __fields_chrono_fractional{
+ .__precision_ = true, .__locale_specific_form_ = true, .__type_ = false};
+inline constexpr __fields __fields_chrono{.__locale_specific_form_ = true, .__type_ = false};
+
+/// Flags available or required in a chrono type.
+///
+/// The caller of the chrono formatter lists the types it has available and the
+/// validation tests whether the requested type spec (e.g. %M) is available in
+/// the formatter.
+/// When the type in the chrono-format-spec isn't present in the data a
+/// \ref format_error is thrown.
+enum class __flags {
+ __second = 0x1,
+ __minute = 0x2,
+ __hour = 0x4,
+ __time = __hour | __minute | __second,
+
+ __day = 0x8,
+ __month = 0x10,
+ __year = 0x20,
+
+ __weekday = 0x40,
+
+ __month_day = __day | __month,
+ __month_weekday = __weekday | __month,
+ __year_month = __month | __year,
+ __date = __day | __month | __year | __weekday,
+
+ __date_time = __date | __time,
+
+ __duration = 0x80 | __time,
+
+ __time_zone = 0x100,
+
+ __clock = __date_time | __time_zone
+};
+
+_LIBCPP_HIDE_FROM_ABI constexpr __flags operator&(__flags __lhs, __flags __rhs) {
+ return static_cast<__flags>(static_cast<unsigned>(__lhs) & static_cast<unsigned>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_second(__flags __flags) {
+ if ((__flags & __flags::__second) != __flags::__second)
+ std::__throw_format_error("The supplied date time doesn't contain a second");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_minute(__flags __flags) {
+ if ((__flags & __flags::__minute) != __flags::__minute)
+ std::__throw_format_error("The supplied date time doesn't contain a minute");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_hour(__flags __flags) {
+ if ((__flags & __flags::__hour) != __flags::__hour)
+ std::__throw_format_error("The supplied date time doesn't contain an hour");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_time(__flags __flags) {
+ if ((__flags & __flags::__time) != __flags::__time)
+ std::__throw_format_error("The supplied date time doesn't contain a time");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_day(__flags __flags) {
+ if ((__flags & __flags::__day) != __flags::__day)
+ std::__throw_format_error("The supplied date time doesn't contain a day");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_month(__flags __flags) {
+ if ((__flags & __flags::__month) != __flags::__month)
+ std::__throw_format_error("The supplied date time doesn't contain a month");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_year(__flags __flags) {
+ if ((__flags & __flags::__year) != __flags::__year)
+ std::__throw_format_error("The supplied date time doesn't contain a year");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_date(__flags __flags) {
+ if ((__flags & __flags::__date) != __flags::__date)
+ std::__throw_format_error("The supplied date time doesn't contain a date");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_date_or_duration(__flags __flags) {
+ if (((__flags & __flags::__date) != __flags::__date) && ((__flags & __flags::__duration) != __flags::__duration))
+ std::__throw_format_error("The supplied date time doesn't contain a date or duration");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_date_time(__flags __flags) {
+ if ((__flags & __flags::__date_time) != __flags::__date_time)
+ std::__throw_format_error("The supplied date time doesn't contain a date and time");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_weekday(__flags __flags) {
+ if ((__flags & __flags::__weekday) != __flags::__weekday)
+ std::__throw_format_error("The supplied date time doesn't contain a weekday");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_duration(__flags __flags) {
+ if ((__flags & __flags::__duration) != __flags::__duration)
+ std::__throw_format_error("The supplied date time doesn't contain a duration");
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __validate_time_zone(__flags __flags) {
+ if ((__flags & __flags::__time_zone) != __flags::__time_zone)
+ std::__throw_format_error("The supplied date time doesn't contain a time zone");
+}
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS __parser_chrono {
+ using _ConstIterator = typename basic_format_parse_context<_CharT>::const_iterator;
+
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator
+ __parse(_ParseContext& __ctx, __fields __fields, __flags __flags) {
+ _ConstIterator __begin = __parser_.__parse(__ctx, __fields);
+ _ConstIterator __end = __ctx.end();
+ if (__begin == __end)
+ return __begin;
+
+ _ConstIterator __last = __parse_chrono_specs(__begin, __end, __flags);
+ __chrono_specs_ = basic_string_view<_CharT>{__begin, __last};
+
+ return __last;
+ }
+
+ __parser<_CharT> __parser_;
+ basic_string_view<_CharT> __chrono_specs_;
+
+private:
+ _LIBCPP_HIDE_FROM_ABI constexpr _ConstIterator
+ __parse_chrono_specs(_ConstIterator __begin, _ConstIterator __end, __flags __flags) {
+ _LIBCPP_ASSERT_INTERNAL(__begin != __end,
+ "When called with an empty input the function will cause "
+ "undefined behavior by evaluating data not in the input");
+
+ if (*__begin != _CharT('%') && *__begin != _CharT('}'))
+ std::__throw_format_error("The format specifier expects a '%' or a '}'");
+
+ do {
+ switch (*__begin) {
+ case _CharT('{'):
+ std::__throw_format_error("The chrono specifiers contain a '{'");
+
+ case _CharT('}'):
+ return __begin;
+
+ case _CharT('%'):
+ __parse_conversion_spec(__begin, __end, __flags);
+ [[fallthrough]];
+
+ default:
+ // All other literals
+ ++__begin;
+ }
+
+ } while (__begin != __end && *__begin != _CharT('}'));
+
+ return __begin;
+ }
+
+ /// \pre *__begin == '%'
+ /// \post __begin points at the end parsed conversion-spec
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ __parse_conversion_spec(_ConstIterator& __begin, _ConstIterator __end, __flags __flags) {
+ ++__begin;
+ if (__begin == __end)
+ std::__throw_format_error("End of input while parsing a conversion specifier");
+
+ switch (*__begin) {
+ case _CharT('n'):
+ case _CharT('t'):
+ case _CharT('%'):
+ break;
+
+ case _CharT('S'):
+ __format_spec::__validate_second(__flags);
+ break;
+
+ case _CharT('M'):
+ __format_spec::__validate_minute(__flags);
+ break;
+
+ case _CharT('p'): // TODO FMT does the formater require an hour or a time?
+ case _CharT('H'):
+ case _CharT('I'):
+ __parser_.__hour_ = true;
+ __validate_hour(__flags);
+ break;
+
+ case _CharT('r'):
+ case _CharT('R'):
+ case _CharT('T'):
+ case _CharT('X'):
+ __parser_.__hour_ = true;
+ __format_spec::__validate_time(__flags);
+ break;
+
+ case _CharT('d'):
+ case _CharT('e'):
+ __format_spec::__validate_day(__flags);
+ break;
+
+ case _CharT('b'):
+ case _CharT('h'):
+ case _CharT('B'):
+ __parser_.__month_name_ = true;
+ [[fallthrough]];
+ case _CharT('m'):
+ __format_spec::__validate_month(__flags);
+ break;
+
+ case _CharT('y'):
+ case _CharT('C'):
+ case _CharT('Y'):
+ __format_spec::__validate_year(__flags);
+ break;
+
+ case _CharT('j'):
+ __parser_.__day_of_year_ = true;
+ __format_spec::__validate_date_or_duration(__flags);
+ break;
+
+ case _CharT('g'):
+ case _CharT('G'):
+ case _CharT('U'):
+ case _CharT('V'):
+ case _CharT('W'):
+ __parser_.__week_of_year_ = true;
+ [[fallthrough]];
+ case _CharT('x'):
+ case _CharT('D'):
+ case _CharT('F'):
+ __format_spec::__validate_date(__flags);
+ break;
+
+ case _CharT('c'):
+ __format_spec::__validate_date_time(__flags);
+ break;
+
+ case _CharT('a'):
+ case _CharT('A'):
+ __parser_.__weekday_name_ = true;
+ [[fallthrough]];
+ case _CharT('u'):
+ case _CharT('w'):
+ __parser_.__weekday_ = true;
+ __validate_weekday(__flags);
+ __format_spec::__validate_weekday(__flags);
+ break;
+
+ case _CharT('q'):
+ case _CharT('Q'):
+ __format_spec::__validate_duration(__flags);
+ break;
+
+ case _CharT('E'):
+ __parse_modifier_E(__begin, __end, __flags);
+ break;
+
+ case _CharT('O'):
+ __parse_modifier_O(__begin, __end, __flags);
+ break;
+
+ case _CharT('z'):
+ case _CharT('Z'):
+ // Currently there's no time zone information. However some clocks have a
+ // hard-coded "time zone", for these clocks the information can be used.
+ // TODO FMT implement time zones.
+ __format_spec::__validate_time_zone(__flags);
+ break;
+
+ default: // unknown type;
+ std::__throw_format_error("The date time type specifier is invalid");
+ }
+ }
+
+ /// \pre *__begin == 'E'
+ /// \post __begin is incremented by one.
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ __parse_modifier_E(_ConstIterator& __begin, _ConstIterator __end, __flags __flags) {
+ ++__begin;
+ if (__begin == __end)
+ std::__throw_format_error("End of input while parsing the modifier E");
+
+ switch (*__begin) {
+ case _CharT('X'):
+ __parser_.__hour_ = true;
+ __format_spec::__validate_time(__flags);
+ break;
+
+ case _CharT('y'):
+ case _CharT('C'):
+ case _CharT('Y'):
+ __format_spec::__validate_year(__flags);
+ break;
+
+ case _CharT('x'):
+ __format_spec::__validate_date(__flags);
+ break;
+
+ case _CharT('c'):
+ __format_spec::__validate_date_time(__flags);
+ break;
+
+ case _CharT('z'):
+ // Currently there's no time zone information. However some clocks have a
+ // hard-coded "time zone", for these clocks the information can be used.
+ // TODO FMT implement time zones.
+ __format_spec::__validate_time_zone(__flags);
+ break;
+
+ default:
+ std::__throw_format_error("The date time type specifier for modifier E is invalid");
+ }
+ }
+
+ /// \pre *__begin == 'O'
+ /// \post __begin is incremented by one.
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ __parse_modifier_O(_ConstIterator& __begin, _ConstIterator __end, __flags __flags) {
+ ++__begin;
+ if (__begin == __end)
+ std::__throw_format_error("End of input while parsing the modifier O");
+
+ switch (*__begin) {
+ case _CharT('S'):
+ __format_spec::__validate_second(__flags);
+ break;
+
+ case _CharT('M'):
+ __format_spec::__validate_minute(__flags);
+ break;
+
+ case _CharT('I'):
+ case _CharT('H'):
+ __parser_.__hour_ = true;
+ __format_spec::__validate_hour(__flags);
+ break;
+
+ case _CharT('d'):
+ case _CharT('e'):
+ __format_spec::__validate_day(__flags);
+ break;
+
+ case _CharT('m'):
+ __format_spec::__validate_month(__flags);
+ break;
+
+ case _CharT('y'):
+ __format_spec::__validate_year(__flags);
+ break;
+
+ case _CharT('U'):
+ case _CharT('V'):
+ case _CharT('W'):
+ __parser_.__week_of_year_ = true;
+ __format_spec::__validate_date(__flags);
+ break;
+
+ case _CharT('u'):
+ case _CharT('w'):
+ __parser_.__weekday_ = true;
+ __format_spec::__validate_weekday(__flags);
+ break;
+
+ case _CharT('z'):
+ // Currently there's no time zone information. However some clocks have a
+ // hard-coded "time zone", for these clocks the information can be used.
+ // TODO FMT implement time zones.
+ __format_spec::__validate_time_zone(__flags);
+ break;
+
+ default:
+ std::__throw_format_error("The date time type specifier for modifier O is invalid");
+ }
+ }
+};
+
+} // namespace __format_spec
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHRONO_PARSER_STD_FORMAT_SPEC_H
diff --git a/libcxx/include/__cxx03/__chrono/statically_widen.h b/libcxx/include/__cxx03/__chrono/statically_widen.h
new file mode 100644
index 00000000000000..a18c46f057a819
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/statically_widen.h
@@ -0,0 +1,52 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_STATICALLY_WIDEN_H
+#define _LIBCPP___CHRONO_STATICALLY_WIDEN_H
+
+// Implements the STATICALLY-WIDEN exposition-only function. ([time.general]/2)
+
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/concepts.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <__fmt_char_type _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr const _CharT* __statically_widen(const char* __str, const wchar_t* __wstr) {
+ if constexpr (same_as<_CharT, char>)
+ return __str;
+ else
+ return __wstr;
+}
+# define _LIBCPP_STATICALLY_WIDEN(_CharT, __str) ::std::__statically_widen<_CharT>(__str, L##__str)
+# else // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+// Without this indirection the unit test test/libcxx/modules_include.sh.cpp
+// fails for the CI build "No wide characters". This seems like a bug.
+// TODO FMT investigate why this is needed.
+template <__fmt_char_type _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr const _CharT* __statically_widen(const char* __str) {
+ return __str;
+}
+# define _LIBCPP_STATICALLY_WIDEN(_CharT, __str) ::std::__statically_widen<_CharT>(__str)
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHRONO_STATICALLY_WIDEN_H
diff --git a/libcxx/include/__cxx03/__chrono/steady_clock.h b/libcxx/include/__cxx03/__chrono/steady_clock.h
new file mode 100644
index 00000000000000..612a7f156e6343
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/steady_clock.h
@@ -0,0 +1,42 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_STEADY_CLOCK_H
+#define _LIBCPP___CHRONO_STEADY_CLOCK_H
+
+#include <__chrono/duration.h>
+#include <__chrono/time_point.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+#ifndef _LIBCPP_HAS_NO_MONOTONIC_CLOCK
+class _LIBCPP_EXPORTED_FROM_ABI steady_clock {
+public:
+ typedef nanoseconds duration;
+ typedef duration::rep rep;
+ typedef duration::period period;
+ typedef chrono::time_point<steady_clock, duration> time_point;
+ static _LIBCPP_CONSTEXPR_SINCE_CXX14 const bool is_steady = true;
+
+ static time_point now() _NOEXCEPT;
+};
+#endif
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHRONO_STEADY_CLOCK_H
diff --git a/libcxx/include/__cxx03/__chrono/sys_info.h b/libcxx/include/__cxx03/__chrono/sys_info.h
new file mode 100644
index 00000000000000..11536cbde3a37c
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/sys_info.h
@@ -0,0 +1,51 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_SYS_INFO_H
+#define _LIBCPP___CHRONO_SYS_INFO_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__chrono/duration.h>
+# include <__chrono/system_clock.h>
+# include <__chrono/time_point.h>
+# include <__config>
+# include <string>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20
+
+namespace chrono {
+
+struct sys_info {
+ sys_seconds begin;
+ sys_seconds end;
+ seconds offset;
+ minutes save;
+ string abbrev;
+};
+
+} // namespace chrono
+
+# endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_SYS_INFO_H
diff --git a/libcxx/include/__cxx03/__chrono/system_clock.h b/libcxx/include/__cxx03/__chrono/system_clock.h
new file mode 100644
index 00000000000000..5a9eb65bdae7ac
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/system_clock.h
@@ -0,0 +1,52 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_SYSTEM_CLOCK_H
+#define _LIBCPP___CHRONO_SYSTEM_CLOCK_H
+
+#include <__chrono/duration.h>
+#include <__chrono/time_point.h>
+#include <__config>
+#include <ctime>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class _LIBCPP_EXPORTED_FROM_ABI system_clock {
+public:
+ typedef microseconds duration;
+ typedef duration::rep rep;
+ typedef duration::period period;
+ typedef chrono::time_point<system_clock> time_point;
+ static _LIBCPP_CONSTEXPR_SINCE_CXX14 const bool is_steady = false;
+
+ static time_point now() _NOEXCEPT;
+ static time_t to_time_t(const time_point& __t) _NOEXCEPT;
+ static time_point from_time_t(time_t __t) _NOEXCEPT;
+};
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Duration>
+using sys_time = time_point<system_clock, _Duration>;
+using sys_seconds = sys_time<seconds>;
+using sys_days = sys_time<days>;
+
+#endif
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHRONO_SYSTEM_CLOCK_H
diff --git a/libcxx/include/__cxx03/__chrono/time_point.h b/libcxx/include/__cxx03/__chrono/time_point.h
new file mode 100644
index 00000000000000..aaf0b098f280e0
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/time_point.h
@@ -0,0 +1,220 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_TIME_POINT_H
+#define _LIBCPP___CHRONO_TIME_POINT_H
+
+#include <__chrono/duration.h>
+#include <__compare/ordering.h>
+#include <__compare/three_way_comparable.h>
+#include <__config>
+#include <__type_traits/common_type.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_convertible.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+template <class _Clock, class _Duration = typename _Clock::duration>
+class _LIBCPP_TEMPLATE_VIS time_point {
+ static_assert(__is_duration<_Duration>::value,
+ "Second template parameter of time_point must be a std::chrono::duration");
+
+public:
+ typedef _Clock clock;
+ typedef _Duration duration;
+ typedef typename duration::rep rep;
+ typedef typename duration::period period;
+
+private:
+ duration __d_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 time_point() : __d_(duration::zero()) {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit time_point(const duration& __d) : __d_(__d) {}
+
+ // conversions
+ template <class _Duration2, __enable_if_t<is_convertible<_Duration2, duration>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 time_point(const time_point<clock, _Duration2>& __t)
+ : __d_(__t.time_since_epoch()) {}
+
+ // observer
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 duration time_since_epoch() const { return __d_; }
+
+ // arithmetic
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 time_point& operator+=(const duration& __d) {
+ __d_ += __d;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 time_point& operator-=(const duration& __d) {
+ __d_ -= __d;
+ return *this;
+ }
+
+ // special values
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR time_point min() _NOEXCEPT { return time_point(duration::min()); }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR time_point max() _NOEXCEPT { return time_point(duration::max()); }
+};
+
+} // namespace chrono
+
+template <class _Clock, class _Duration1, class _Duration2>
+struct _LIBCPP_TEMPLATE_VIS
+common_type<chrono::time_point<_Clock, _Duration1>, chrono::time_point<_Clock, _Duration2> > {
+ typedef chrono::time_point<_Clock, typename common_type<_Duration1, _Duration2>::type> type;
+};
+
+namespace chrono {
+
+template <class _ToDuration, class _Clock, class _Duration>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 time_point<_Clock, _ToDuration>
+time_point_cast(const time_point<_Clock, _Duration>& __t) {
+ return time_point<_Clock, _ToDuration>(chrono::duration_cast<_ToDuration>(__t.time_since_epoch()));
+}
+
+#if _LIBCPP_STD_VER >= 17
+template <class _ToDuration, class _Clock, class _Duration, enable_if_t<__is_duration<_ToDuration>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI constexpr time_point<_Clock, _ToDuration> floor(const time_point<_Clock, _Duration>& __t) {
+ return time_point<_Clock, _ToDuration>{chrono::floor<_ToDuration>(__t.time_since_epoch())};
+}
+
+template <class _ToDuration, class _Clock, class _Duration, enable_if_t<__is_duration<_ToDuration>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI constexpr time_point<_Clock, _ToDuration> ceil(const time_point<_Clock, _Duration>& __t) {
+ return time_point<_Clock, _ToDuration>{chrono::ceil<_ToDuration>(__t.time_since_epoch())};
+}
+
+template <class _ToDuration, class _Clock, class _Duration, enable_if_t<__is_duration<_ToDuration>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI constexpr time_point<_Clock, _ToDuration> round(const time_point<_Clock, _Duration>& __t) {
+ return time_point<_Clock, _ToDuration>{chrono::round<_ToDuration>(__t.time_since_epoch())};
+}
+
+template <class _Rep, class _Period, enable_if_t<numeric_limits<_Rep>::is_signed, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI constexpr duration<_Rep, _Period> abs(duration<_Rep, _Period> __d) {
+ return __d >= __d.zero() ? +__d : -__d;
+}
+#endif // _LIBCPP_STD_VER >= 17
+
+// time_point ==
+
+template <class _Clock, class _Duration1, class _Duration2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator==(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return __lhs.time_since_epoch() == __rhs.time_since_epoch();
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+// time_point !=
+
+template <class _Clock, class _Duration1, class _Duration2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator!=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return !(__lhs == __rhs);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+// time_point <
+
+template <class _Clock, class _Duration1, class _Duration2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator<(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return __lhs.time_since_epoch() < __rhs.time_since_epoch();
+}
+
+// time_point >
+
+template <class _Clock, class _Duration1, class _Duration2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator>(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return __rhs < __lhs;
+}
+
+// time_point <=
+
+template <class _Clock, class _Duration1, class _Duration2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator<=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return !(__rhs < __lhs);
+}
+
+// time_point >=
+
+template <class _Clock, class _Duration1, class _Duration2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator>=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return !(__lhs < __rhs);
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Clock, class _Duration1, three_way_comparable_with<_Duration1> _Duration2>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+operator<=>(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return __lhs.time_since_epoch() <=> __rhs.time_since_epoch();
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+// time_point operator+(time_point x, duration y);
+
+template <class _Clock, class _Duration1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX14 time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type>
+operator+(const time_point<_Clock, _Duration1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ typedef time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type> _Tr;
+ return _Tr(__lhs.time_since_epoch() + __rhs);
+}
+
+// time_point operator+(duration x, time_point y);
+
+template <class _Rep1, class _Period1, class _Clock, class _Duration2>
+inline _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX14 time_point<_Clock, typename common_type<duration<_Rep1, _Period1>, _Duration2>::type>
+operator+(const duration<_Rep1, _Period1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return __rhs + __lhs;
+}
+
+// time_point operator-(time_point x, duration y);
+
+template <class _Clock, class _Duration1, class _Rep2, class _Period2>
+inline _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX14 time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type>
+operator-(const time_point<_Clock, _Duration1>& __lhs, const duration<_Rep2, _Period2>& __rhs) {
+ typedef time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type> _Ret;
+ return _Ret(__lhs.time_since_epoch() - __rhs);
+}
+
+// duration operator-(time_point x, time_point y);
+
+template <class _Clock, class _Duration1, class _Duration2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename common_type<_Duration1, _Duration2>::type
+operator-(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs) {
+ return __lhs.time_since_epoch() - __rhs.time_since_epoch();
+}
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHRONO_TIME_POINT_H
diff --git a/libcxx/include/__cxx03/__chrono/time_zone.h b/libcxx/include/__cxx03/__chrono/time_zone.h
new file mode 100644
index 00000000000000..de11dac1eef0c2
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/time_zone.h
@@ -0,0 +1,182 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_TIME_ZONE_H
+#define _LIBCPP___CHRONO_TIME_ZONE_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__chrono/calendar.h>
+# include <__chrono/duration.h>
+# include <__chrono/exception.h>
+# include <__chrono/local_info.h>
+# include <__chrono/sys_info.h>
+# include <__chrono/system_clock.h>
+# include <__compare/strong_order.h>
+# include <__config>
+# include <__memory/unique_ptr.h>
+# include <__type_traits/common_type.h>
+# include <string_view>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+namespace chrono {
+
+enum class choose { earliest, latest };
+
+class _LIBCPP_AVAILABILITY_TZDB time_zone {
+ _LIBCPP_HIDE_FROM_ABI time_zone() = default;
+
+public:
+ class __impl; // public so it can be used by make_unique.
+
+ // The "constructor".
+ //
+ // The default constructor is private to avoid the constructor from being
+ // part of the ABI. Instead use an __ugly_named function as an ABI interface,
+ // since that gives us the ability to change it in the future.
+ [[nodiscard]] _LIBCPP_EXPORTED_FROM_ABI static time_zone __create(unique_ptr<__impl>&& __p);
+
+ _LIBCPP_EXPORTED_FROM_ABI ~time_zone();
+
+ _LIBCPP_HIDE_FROM_ABI time_zone(time_zone&&) = default;
+ _LIBCPP_HIDE_FROM_ABI time_zone& operator=(time_zone&&) = default;
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI string_view name() const noexcept { return __name(); }
+
+ template <class _Duration>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI sys_info get_info(const sys_time<_Duration>& __time) const {
+ return __get_info(chrono::time_point_cast<seconds>(__time));
+ }
+
+ template <class _Duration>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI local_info get_info(const local_time<_Duration>& __time) const {
+ return __get_info(chrono::time_point_cast<seconds>(__time));
+ }
+
+ // We don't apply nodiscard here since this function throws on many inputs,
+ // so it could be used as a validation.
+ template <class _Duration>
+ _LIBCPP_HIDE_FROM_ABI sys_time<common_type_t<_Duration, seconds>> to_sys(const local_time<_Duration>& __time) const {
+ local_info __info = get_info(__time);
+ switch (__info.result) {
+ case local_info::unique:
+ return sys_time<common_type_t<_Duration, seconds>>{__time.time_since_epoch() - __info.first.offset};
+
+ case local_info::nonexistent:
+ chrono::__throw_nonexistent_local_time(__time, __info);
+
+ case local_info::ambiguous:
+ chrono::__throw_ambiguous_local_time(__time, __info);
+ }
+
+ // TODO TZDB The Standard does not specify anything in these cases.
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __info.result != -1, "cannot convert the local time; it would be before the minimum system clock value");
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __info.result != -2, "cannot convert the local time; it would be after the maximum system clock value");
+
+ return {};
+ }
+
+ template <class _Duration>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI sys_time<common_type_t<_Duration, seconds>>
+ to_sys(const local_time<_Duration>& __time, choose __z) const {
+ local_info __info = get_info(__time);
+ switch (__info.result) {
+ case local_info::unique:
+ case local_info::nonexistent: // first and second are the same
+ return sys_time<common_type_t<_Duration, seconds>>{__time.time_since_epoch() - __info.first.offset};
+
+ case local_info::ambiguous:
+ switch (__z) {
+ case choose::earliest:
+ return sys_time<common_type_t<_Duration, seconds>>{__time.time_since_epoch() - __info.first.offset};
+
+ case choose::latest:
+ return sys_time<common_type_t<_Duration, seconds>>{__time.time_since_epoch() - __info.second.offset};
+
+ // Note a value out of bounds is not specified.
+ }
+ }
+
+ // TODO TZDB The standard does not specify anything in these cases.
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __info.result != -1, "cannot convert the local time; it would be before the minimum system clock value");
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __info.result != -2, "cannot convert the local time; it would be after the maximum system clock value");
+
+ return {};
+ }
+
+ template <class _Duration>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI local_time<common_type_t<_Duration, seconds>>
+ to_local(const sys_time<_Duration>& __time) const {
+ using _Dp = common_type_t<_Duration, seconds>;
+
+ sys_info __info = get_info(__time);
+
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __info.offset >= chrono::seconds{0} || __time.time_since_epoch() >= _Dp::min() - __info.offset,
+ "cannot convert the system time; it would be before the minimum local clock value");
+
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __info.offset <= chrono::seconds{0} || __time.time_since_epoch() <= _Dp::max() - __info.offset,
+ "cannot convert the system time; it would be after the maximum local clock value");
+
+ return local_time<_Dp>{__time.time_since_epoch() + __info.offset};
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI const __impl& __implementation() const noexcept { return *__impl_; }
+
+private:
+ [[nodiscard]] _LIBCPP_EXPORTED_FROM_ABI string_view __name() const noexcept;
+
+ [[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_EXPORTED_FROM_ABI sys_info __get_info(sys_seconds __time) const;
+ [[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_EXPORTED_FROM_ABI local_info __get_info(local_seconds __time) const;
+
+ unique_ptr<__impl> __impl_;
+};
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline bool
+operator==(const time_zone& __x, const time_zone& __y) noexcept {
+ return __x.name() == __y.name();
+}
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline strong_ordering
+operator<=>(const time_zone& __x, const time_zone& __y) noexcept {
+ return __x.name() <=> __y.name();
+}
+
+} // namespace chrono
+
+# endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+ // && !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_TIME_ZONE_H
diff --git a/libcxx/include/__cxx03/__chrono/time_zone_link.h b/libcxx/include/__cxx03/__chrono/time_zone_link.h
new file mode 100644
index 00000000000000..b2d365c5fd0820
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/time_zone_link.h
@@ -0,0 +1,79 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_TIME_ZONE_LINK_H
+#define _LIBCPP___CHRONO_TIME_ZONE_LINK_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__compare/strong_order.h>
+# include <__config>
+# include <__utility/private_constructor_tag.h>
+# include <string>
+# include <string_view>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+namespace chrono {
+
+class time_zone_link {
+public:
+ [[nodiscard]]
+ _LIBCPP_HIDE_FROM_ABI explicit time_zone_link(__private_constructor_tag, string_view __name, string_view __target)
+ : __name_{__name}, __target_{__target} {}
+
+ _LIBCPP_HIDE_FROM_ABI time_zone_link(time_zone_link&&) = default;
+ _LIBCPP_HIDE_FROM_ABI time_zone_link& operator=(time_zone_link&&) = default;
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI string_view name() const noexcept { return __name_; }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI string_view target() const noexcept { return __target_; }
+
+private:
+ string __name_;
+ // TODO TZDB instead of the name we can store the pointer to a zone. These
+ // pointers are immutable. This makes it possible to directly return a
+ // pointer in the time_zone in the 'locate_zone' function.
+ string __target_;
+};
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline bool
+operator==(const time_zone_link& __x, const time_zone_link& __y) noexcept {
+ return __x.name() == __y.name();
+}
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline strong_ordering
+operator<=>(const time_zone_link& __x, const time_zone_link& __y) noexcept {
+ return __x.name() <=> __y.name();
+}
+
+} // namespace chrono
+
+# endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_TIME_ZONE_LINK_H
diff --git a/libcxx/include/__cxx03/__chrono/tzdb.h b/libcxx/include/__cxx03/__chrono/tzdb.h
new file mode 100644
index 00000000000000..f731f8c318be07
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/tzdb.h
@@ -0,0 +1,94 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_TZDB_H
+#define _LIBCPP___CHRONO_TZDB_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__algorithm/ranges_lower_bound.h>
+# include <__chrono/leap_second.h>
+# include <__chrono/time_zone.h>
+# include <__chrono/time_zone_link.h>
+# include <__config>
+# include <string>
+# include <vector>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+namespace chrono {
+
+struct tzdb {
+ string version;
+ vector<time_zone> zones;
+ vector<time_zone_link> links;
+
+ vector<leap_second> leap_seconds;
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI const time_zone* __locate_zone(string_view __name) const {
+ if (const time_zone* __result = __find_in_zone(__name))
+ return __result;
+
+ if (auto __it = ranges::lower_bound(links, __name, {}, &time_zone_link::name);
+ __it != links.end() && __it->name() == __name)
+ if (const time_zone* __result = __find_in_zone(__it->target()))
+ return __result;
+
+ return nullptr;
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI const time_zone* locate_zone(string_view __name) const {
+ if (const time_zone* __result = __locate_zone(__name))
+ return __result;
+
+ std::__throw_runtime_error("tzdb: requested time zone not found");
+ }
+
+ [[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI const time_zone* current_zone() const {
+ return __current_zone();
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI const time_zone* __find_in_zone(string_view __name) const noexcept {
+ if (auto __it = ranges::lower_bound(zones, __name, {}, &time_zone::name);
+ __it != zones.end() && __it->name() == __name)
+ return std::addressof(*__it);
+
+ return nullptr;
+ }
+
+ [[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_EXPORTED_FROM_ABI const time_zone* __current_zone() const;
+};
+
+} // namespace chrono
+
+# endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+ // && !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_TZDB_H
diff --git a/libcxx/include/__cxx03/__chrono/tzdb_list.h b/libcxx/include/__cxx03/__chrono/tzdb_list.h
new file mode 100644
index 00000000000000..aeef4fe1aba3c1
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/tzdb_list.h
@@ -0,0 +1,108 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_TZDB_LIST_H
+#define _LIBCPP___CHRONO_TZDB_LIST_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__chrono/time_zone.h>
+# include <__chrono/tzdb.h>
+# include <__config>
+# include <__fwd/string.h>
+# include <forward_list>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+namespace chrono {
+
+// TODO TZDB
+// Libc++ recently switched to only export __ugly_names from the dylib.
+// Since the library is still experimental the functions in this header
+// should be adapted to this new style. The other tzdb headers should be
+// evaluated too.
+
+class _LIBCPP_AVAILABILITY_TZDB tzdb_list {
+public:
+ class __impl; // public to allow construction in dylib
+ _LIBCPP_HIDE_FROM_ABI explicit tzdb_list(__impl* __p) : __impl_(__p) {
+ _LIBCPP_ASSERT_NON_NULL(__impl_ != nullptr, "initialized time_zone without a valid pimpl object");
+ }
+ _LIBCPP_EXPORTED_FROM_ABI ~tzdb_list();
+
+ tzdb_list(const tzdb_list&) = delete;
+ tzdb_list& operator=(const tzdb_list&) = delete;
+
+ using const_iterator = forward_list<tzdb>::const_iterator;
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI const tzdb& front() const noexcept { return __front(); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator erase_after(const_iterator __p) { return __erase_after(__p); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI const_iterator begin() const noexcept { return __begin(); }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI const_iterator end() const noexcept { return __end(); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const noexcept { return __cbegin(); }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI const_iterator cend() const noexcept { return __cend(); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI __impl& __implementation() { return *__impl_; }
+
+private:
+ [[nodiscard]] _LIBCPP_EXPORTED_FROM_ABI const tzdb& __front() const noexcept;
+
+ _LIBCPP_EXPORTED_FROM_ABI const_iterator __erase_after(const_iterator __p);
+
+ [[nodiscard]] _LIBCPP_EXPORTED_FROM_ABI const_iterator __begin() const noexcept;
+ [[nodiscard]] _LIBCPP_EXPORTED_FROM_ABI const_iterator __end() const noexcept;
+
+ [[nodiscard]] _LIBCPP_EXPORTED_FROM_ABI const_iterator __cbegin() const noexcept;
+ [[nodiscard]] _LIBCPP_EXPORTED_FROM_ABI const_iterator __cend() const noexcept;
+
+ __impl* __impl_;
+};
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_EXPORTED_FROM_ABI tzdb_list& get_tzdb_list();
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline const tzdb& get_tzdb() {
+ return get_tzdb_list().front();
+}
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline const time_zone* locate_zone(string_view __name) {
+ return get_tzdb().locate_zone(__name);
+}
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline const time_zone* current_zone() {
+ return get_tzdb().current_zone();
+}
+
+_LIBCPP_AVAILABILITY_TZDB _LIBCPP_EXPORTED_FROM_ABI const tzdb& reload_tzdb();
+
+[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_EXPORTED_FROM_ABI string remote_version();
+
+} // namespace chrono
+
+# endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+ // && !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_TZDB_LIST_H
diff --git a/libcxx/include/__cxx03/__chrono/weekday.h b/libcxx/include/__cxx03/__chrono/weekday.h
new file mode 100644
index 00000000000000..86c780cc718256
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/weekday.h
@@ -0,0 +1,186 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_WEEKDAY_H
+#define _LIBCPP___CHRONO_WEEKDAY_H
+
+#include <__chrono/calendar.h>
+#include <__chrono/duration.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/time_point.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class weekday_indexed;
+class weekday_last;
+
+class weekday {
+private:
+ unsigned char __wd_;
+ _LIBCPP_HIDE_FROM_ABI static constexpr unsigned char __weekday_from_days(int __days) noexcept;
+
+public:
+ weekday() = default;
+ _LIBCPP_HIDE_FROM_ABI inline explicit constexpr weekday(unsigned __val) noexcept
+ : __wd_(static_cast<unsigned char>(__val == 7 ? 0 : __val)) {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr weekday(const sys_days& __sysd) noexcept
+ : __wd_(__weekday_from_days(__sysd.time_since_epoch().count())) {}
+ _LIBCPP_HIDE_FROM_ABI inline explicit constexpr weekday(const local_days& __locd) noexcept
+ : __wd_(__weekday_from_days(__locd.time_since_epoch().count())) {}
+
+ _LIBCPP_HIDE_FROM_ABI inline constexpr weekday& operator++() noexcept {
+ __wd_ = (__wd_ == 6 ? 0 : __wd_ + 1);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr weekday operator++(int) noexcept {
+ weekday __tmp = *this;
+ ++(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr weekday& operator--() noexcept {
+ __wd_ = (__wd_ == 0 ? 6 : __wd_ - 1);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr weekday operator--(int) noexcept {
+ weekday __tmp = *this;
+ --(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr weekday& operator+=(const days& __dd) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr weekday& operator-=(const days& __dd) noexcept;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr unsigned c_encoding() const noexcept { return __wd_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr unsigned iso_encoding() const noexcept { return __wd_ == 0u ? 7 : __wd_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __wd_ <= 6; }
+ _LIBCPP_HIDE_FROM_ABI constexpr weekday_indexed operator[](unsigned __index) const noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr weekday_last operator[](last_spec) const noexcept;
+};
+
+// https://howardhinnant.github.io/date_algorithms.html#weekday_from_days
+_LIBCPP_HIDE_FROM_ABI inline constexpr unsigned char weekday::__weekday_from_days(int __days) noexcept {
+ return static_cast<unsigned char>(static_cast<unsigned>(__days >= -4 ? (__days + 4) % 7 : (__days + 5) % 7 + 6));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(const weekday& __lhs, const weekday& __rhs) noexcept {
+ return __lhs.c_encoding() == __rhs.c_encoding();
+}
+
+// TODO(LLVM 20): Remove the escape hatch
+# ifdef _LIBCPP_ENABLE_REMOVED_WEEKDAY_RELATIONAL_OPERATORS
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator<(const weekday& __lhs, const weekday& __rhs) noexcept {
+ return __lhs.c_encoding() < __rhs.c_encoding();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator>(const weekday& __lhs, const weekday& __rhs) noexcept {
+ return __rhs < __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator<=(const weekday& __lhs, const weekday& __rhs) noexcept {
+ return !(__rhs < __lhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator>=(const weekday& __lhs, const weekday& __rhs) noexcept {
+ return !(__lhs < __rhs);
+}
+# endif // _LIBCPP_ENABLE_REMOVED_WEEKDAY_RELATIONAL_OPERATORS
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr weekday operator+(const weekday& __lhs, const days& __rhs) noexcept {
+ auto const __mu = static_cast<long long>(__lhs.c_encoding()) + __rhs.count();
+ auto const __yr = (__mu >= 0 ? __mu : __mu - 6) / 7;
+ return weekday{static_cast<unsigned>(__mu - __yr * 7)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr weekday operator+(const days& __lhs, const weekday& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr weekday operator-(const weekday& __lhs, const days& __rhs) noexcept {
+ return __lhs + -__rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr days operator-(const weekday& __lhs, const weekday& __rhs) noexcept {
+ const int __wdu = __lhs.c_encoding() - __rhs.c_encoding();
+ const int __wk = (__wdu >= 0 ? __wdu : __wdu - 6) / 7;
+ return days{__wdu - __wk * 7};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr weekday& weekday::operator+=(const days& __dd) noexcept {
+ *this = *this + __dd;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr weekday& weekday::operator-=(const days& __dd) noexcept {
+ *this = *this - __dd;
+ return *this;
+}
+
+class weekday_indexed {
+private:
+ chrono::weekday __wd_;
+ unsigned char __idx_;
+
+public:
+ weekday_indexed() = default;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr weekday_indexed(const chrono::weekday& __wdval, unsigned __idxval) noexcept
+ : __wd_{__wdval}, __idx_(__idxval) {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::weekday weekday() const noexcept { return __wd_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr unsigned index() const noexcept { return __idx_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __wd_.ok() && __idx_ >= 1 && __idx_ <= 5; }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool
+operator==(const weekday_indexed& __lhs, const weekday_indexed& __rhs) noexcept {
+ return __lhs.weekday() == __rhs.weekday() && __lhs.index() == __rhs.index();
+}
+
+class weekday_last {
+private:
+ chrono::weekday __wd_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr weekday_last(const chrono::weekday& __val) noexcept : __wd_{__val} {}
+ _LIBCPP_HIDE_FROM_ABI constexpr chrono::weekday weekday() const noexcept { return __wd_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr bool ok() const noexcept { return __wd_.ok(); }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(const weekday_last& __lhs, const weekday_last& __rhs) noexcept {
+ return __lhs.weekday() == __rhs.weekday();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr weekday_indexed weekday::operator[](unsigned __index) const noexcept {
+ return weekday_indexed{*this, __index};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr weekday_last weekday::operator[](last_spec) const noexcept {
+ return weekday_last{*this};
+}
+
+inline constexpr weekday Sunday{0};
+inline constexpr weekday Monday{1};
+inline constexpr weekday Tuesday{2};
+inline constexpr weekday Wednesday{3};
+inline constexpr weekday Thursday{4};
+inline constexpr weekday Friday{5};
+inline constexpr weekday Saturday{6};
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_WEEKDAY_H
diff --git a/libcxx/include/__cxx03/__chrono/year.h b/libcxx/include/__cxx03/__chrono/year.h
new file mode 100644
index 00000000000000..1899d09f38dbdb
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/year.h
@@ -0,0 +1,118 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_YEAR_H
+#define _LIBCPP___CHRONO_YEAR_H
+
+#include <__chrono/duration.h>
+#include <__config>
+#include <compare>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class year {
+private:
+ short __y_;
+
+public:
+ year() = default;
+ _LIBCPP_HIDE_FROM_ABI explicit inline constexpr year(int __val) noexcept : __y_(static_cast<short>(__val)) {}
+
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year& operator++() noexcept {
+ ++__y_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year operator++(int) noexcept {
+ year __tmp = *this;
+ ++(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year& operator--() noexcept {
+ --__y_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year operator--(int) noexcept {
+ year __tmp = *this;
+ --(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr year& operator+=(const years& __dy) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year& operator-=(const years& __dy) noexcept;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year operator+() const noexcept { return *this; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year operator-() const noexcept { return year{-__y_}; }
+
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool is_leap() const noexcept {
+ return __y_ % 4 == 0 && (__y_ % 100 != 0 || __y_ % 400 == 0);
+ }
+ _LIBCPP_HIDE_FROM_ABI explicit inline constexpr operator int() const noexcept { return __y_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr bool ok() const noexcept;
+ _LIBCPP_HIDE_FROM_ABI static inline constexpr year min() noexcept { return year{-32767}; }
+ _LIBCPP_HIDE_FROM_ABI static inline constexpr year max() noexcept { return year{32767}; }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(const year& __lhs, const year& __rhs) noexcept {
+ return static_cast<int>(__lhs) == static_cast<int>(__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr strong_ordering operator<=>(const year& __lhs, const year& __rhs) noexcept {
+ return static_cast<int>(__lhs) <=> static_cast<int>(__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year operator+(const year& __lhs, const years& __rhs) noexcept {
+ return year(static_cast<int>(__lhs) + __rhs.count());
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year operator+(const years& __lhs, const year& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year operator-(const year& __lhs, const years& __rhs) noexcept {
+ return __lhs + -__rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr years operator-(const year& __lhs, const year& __rhs) noexcept {
+ return years{static_cast<int>(__lhs) - static_cast<int>(__rhs)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year& year::operator+=(const years& __dy) noexcept {
+ *this = *this + __dy;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year& year::operator-=(const years& __dy) noexcept {
+ *this = *this - __dy;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr bool year::ok() const noexcept {
+ static_assert(static_cast<int>(std::numeric_limits<decltype(__y_)>::max()) == static_cast<int>(max()));
+ return static_cast<int>(min()) <= __y_;
+}
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHRONO_YEAR_H
diff --git a/libcxx/include/__cxx03/__chrono/year_month.h b/libcxx/include/__cxx03/__chrono/year_month.h
new file mode 100644
index 00000000000000..369ea38f7560d9
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/year_month.h
@@ -0,0 +1,123 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_YEAR_MONTH_H
+#define _LIBCPP___CHRONO_YEAR_MONTH_H
+
+#include <__chrono/duration.h>
+#include <__chrono/month.h>
+#include <__chrono/year.h>
+#include <__config>
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class year_month {
+ chrono::year __y_;
+ chrono::month __m_;
+
+public:
+ year_month() = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month(const chrono::year& __yval, const chrono::month& __mval) noexcept
+ : __y_{__yval}, __m_{__mval} {}
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::year year() const noexcept { return __y_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year_month& operator+=(const months& __dm) noexcept;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year_month& operator-=(const months& __dm) noexcept;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year_month& operator+=(const years& __dy) noexcept;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year_month& operator-=(const years& __dy) noexcept;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __y_.ok() && __m_.ok(); }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month operator/(const year& __y, const month& __m) noexcept {
+ return year_month{__y, __m};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month operator/(const year& __y, int __m) noexcept {
+ return year_month{__y, month(__m)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(const year_month& __lhs, const year_month& __rhs) noexcept {
+ return __lhs.year() == __rhs.year() && __lhs.month() == __rhs.month();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering
+operator<=>(const year_month& __lhs, const year_month& __rhs) noexcept {
+ if (auto __c = __lhs.year() <=> __rhs.year(); __c != 0)
+ return __c;
+ return __lhs.month() <=> __rhs.month();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month operator+(const year_month& __lhs, const months& __rhs) noexcept {
+ int __dmi = static_cast<int>(static_cast<unsigned>(__lhs.month())) - 1 + __rhs.count();
+ const int __dy = (__dmi >= 0 ? __dmi : __dmi - 11) / 12;
+ __dmi = __dmi - __dy * 12 + 1;
+ return (__lhs.year() + years(__dy)) / month(static_cast<unsigned>(__dmi));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month operator+(const months& __lhs, const year_month& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month operator+(const year_month& __lhs, const years& __rhs) noexcept {
+ return (__lhs.year() + __rhs) / __lhs.month();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month operator+(const years& __lhs, const year_month& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr months operator-(const year_month& __lhs, const year_month& __rhs) noexcept {
+ return (__lhs.year() - __rhs.year()) +
+ months(static_cast<unsigned>(__lhs.month()) - static_cast<unsigned>(__rhs.month()));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month operator-(const year_month& __lhs, const months& __rhs) noexcept {
+ return __lhs + -__rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month operator-(const year_month& __lhs, const years& __rhs) noexcept {
+ return __lhs + -__rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month& year_month::operator+=(const months& __dm) noexcept {
+ *this = *this + __dm;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month& year_month::operator-=(const months& __dm) noexcept {
+ *this = *this - __dm;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month& year_month::operator+=(const years& __dy) noexcept {
+ *this = *this + __dy;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month& year_month::operator-=(const years& __dy) noexcept {
+ *this = *this - __dy;
+ return *this;
+}
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_YEAR_MONTH_H
diff --git a/libcxx/include/__cxx03/__chrono/year_month_day.h b/libcxx/include/__cxx03/__chrono/year_month_day.h
new file mode 100644
index 00000000000000..b06c0be03e0de4
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/year_month_day.h
@@ -0,0 +1,337 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_YEAR_MONTH_DAY_H
+#define _LIBCPP___CHRONO_YEAR_MONTH_DAY_H
+
+#include <__chrono/calendar.h>
+#include <__chrono/day.h>
+#include <__chrono/duration.h>
+#include <__chrono/month.h>
+#include <__chrono/monthday.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/time_point.h>
+#include <__chrono/year.h>
+#include <__chrono/year_month.h>
+#include <__config>
+#include <compare>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class year_month_day_last;
+
+class year_month_day {
+private:
+ chrono::year __y_;
+ chrono::month __m_;
+ chrono::day __d_;
+
+public:
+ year_month_day() = default;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day(
+ const chrono::year& __yval, const chrono::month& __mval, const chrono::day& __dval) noexcept
+ : __y_{__yval}, __m_{__mval}, __d_{__dval} {}
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day(const year_month_day_last& __ymdl) noexcept;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day(const sys_days& __sysd) noexcept
+ : year_month_day(__from_days(__sysd.time_since_epoch())) {}
+ _LIBCPP_HIDE_FROM_ABI inline explicit constexpr year_month_day(const local_days& __locd) noexcept
+ : year_month_day(__from_days(__locd.time_since_epoch())) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day& operator+=(const months& __dm) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day& operator-=(const months& __dm) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day& operator+=(const years& __dy) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day& operator-=(const years& __dy) noexcept;
+
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::year year() const noexcept { return __y_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::day day() const noexcept { return __d_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr operator sys_days() const noexcept { return sys_days{__to_days()}; }
+ _LIBCPP_HIDE_FROM_ABI inline explicit constexpr operator local_days() const noexcept {
+ return local_days{__to_days()};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool ok() const noexcept;
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr year_month_day __from_days(days __d) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr days __to_days() const noexcept;
+};
+
+// https://howardhinnant.github.io/date_algorithms.html#civil_from_days
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day year_month_day::__from_days(days __d) noexcept {
+ static_assert(numeric_limits<unsigned>::digits >= 18, "");
+ static_assert(numeric_limits<int>::digits >= 20, "");
+ const int __z = __d.count() + 719468;
+ const int __era = (__z >= 0 ? __z : __z - 146096) / 146097;
+ const unsigned __doe = static_cast<unsigned>(__z - __era * 146097); // [0, 146096]
+ const unsigned __yoe = (__doe - __doe / 1460 + __doe / 36524 - __doe / 146096) / 365; // [0, 399]
+ const int __yr = static_cast<int>(__yoe) + __era * 400;
+ const unsigned __doy = __doe - (365 * __yoe + __yoe / 4 - __yoe / 100); // [0, 365]
+ const unsigned __mp = (5 * __doy + 2) / 153; // [0, 11]
+ const unsigned __dy = __doy - (153 * __mp + 2) / 5 + 1; // [1, 31]
+ const unsigned __mth = __mp + (__mp < 10 ? 3 : -9); // [1, 12]
+ return year_month_day{chrono::year{__yr + (__mth <= 2)}, chrono::month{__mth}, chrono::day{__dy}};
+}
+
+// https://howardhinnant.github.io/date_algorithms.html#days_from_civil
+_LIBCPP_HIDE_FROM_ABI inline constexpr days year_month_day::__to_days() const noexcept {
+ static_assert(numeric_limits<unsigned>::digits >= 18, "");
+ static_assert(numeric_limits<int>::digits >= 20, "");
+
+ const int __yr = static_cast<int>(__y_) - (__m_ <= February);
+ const unsigned __mth = static_cast<unsigned>(__m_);
+ const unsigned __dy = static_cast<unsigned>(__d_);
+
+ const int __era = (__yr >= 0 ? __yr : __yr - 399) / 400;
+ const unsigned __yoe = static_cast<unsigned>(__yr - __era * 400); // [0, 399]
+ const unsigned __doy = (153 * (__mth + (__mth > 2 ? -3 : 9)) + 2) / 5 + __dy - 1; // [0, 365]
+ const unsigned __doe = __yoe * 365 + __yoe / 4 - __yoe / 100 + __doy; // [0, 146096]
+ return days{__era * 146097 + static_cast<int>(__doe) - 719468};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool
+operator==(const year_month_day& __lhs, const year_month_day& __rhs) noexcept {
+ return __lhs.year() == __rhs.year() && __lhs.month() == __rhs.month() && __lhs.day() == __rhs.day();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering
+operator<=>(const year_month_day& __lhs, const year_month_day& __rhs) noexcept {
+ if (auto __c = __lhs.year() <=> __rhs.year(); __c != 0)
+ return __c;
+ if (auto __c = __lhs.month() <=> __rhs.month(); __c != 0)
+ return __c;
+ return __lhs.day() <=> __rhs.day();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day operator/(const year_month& __lhs, const day& __rhs) noexcept {
+ return year_month_day{__lhs.year(), __lhs.month(), __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day operator/(const year_month& __lhs, int __rhs) noexcept {
+ return __lhs / day(__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day operator/(const year& __lhs, const month_day& __rhs) noexcept {
+ return __lhs / __rhs.month() / __rhs.day();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day operator/(int __lhs, const month_day& __rhs) noexcept {
+ return year(__lhs) / __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day operator/(const month_day& __lhs, const year& __rhs) noexcept {
+ return __rhs / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day operator/(const month_day& __lhs, int __rhs) noexcept {
+ return year(__rhs) / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day
+operator+(const year_month_day& __lhs, const months& __rhs) noexcept {
+ return (__lhs.year() / __lhs.month() + __rhs) / __lhs.day();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day
+operator+(const months& __lhs, const year_month_day& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day
+operator-(const year_month_day& __lhs, const months& __rhs) noexcept {
+ return __lhs + -__rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day
+operator+(const year_month_day& __lhs, const years& __rhs) noexcept {
+ return (__lhs.year() + __rhs) / __lhs.month() / __lhs.day();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day
+operator+(const years& __lhs, const year_month_day& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day
+operator-(const year_month_day& __lhs, const years& __rhs) noexcept {
+ return __lhs + -__rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day& year_month_day::operator+=(const months& __dm) noexcept {
+ *this = *this + __dm;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day& year_month_day::operator-=(const months& __dm) noexcept {
+ *this = *this - __dm;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day& year_month_day::operator+=(const years& __dy) noexcept {
+ *this = *this + __dy;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day& year_month_day::operator-=(const years& __dy) noexcept {
+ *this = *this - __dy;
+ return *this;
+}
+
+class year_month_day_last {
+private:
+ chrono::year __y_;
+ chrono::month_day_last __mdl_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day_last(const year& __yval, const month_day_last& __mdlval) noexcept
+ : __y_{__yval}, __mdl_{__mdlval} {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day_last& operator+=(const months& __m) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day_last& operator-=(const months& __m) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day_last& operator+=(const years& __y) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_day_last& operator-=(const years& __y) noexcept;
+
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::year year() const noexcept { return __y_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __mdl_.month(); }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month_day_last month_day_last() const noexcept { return __mdl_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr chrono::day day() const noexcept;
+ _LIBCPP_HIDE_FROM_ABI inline constexpr operator sys_days() const noexcept {
+ return sys_days{year() / month() / day()};
+ }
+ _LIBCPP_HIDE_FROM_ABI inline explicit constexpr operator local_days() const noexcept {
+ return local_days{year() / month() / day()};
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __y_.ok() && __mdl_.ok(); }
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr chrono::day year_month_day_last::day() const noexcept {
+ constexpr chrono::day __d[] = {
+ chrono::day(31),
+ chrono::day(28),
+ chrono::day(31),
+ chrono::day(30),
+ chrono::day(31),
+ chrono::day(30),
+ chrono::day(31),
+ chrono::day(31),
+ chrono::day(30),
+ chrono::day(31),
+ chrono::day(30),
+ chrono::day(31)};
+ return (month() != February || !__y_.is_leap()) && month().ok()
+ ? __d[static_cast<unsigned>(month()) - 1]
+ : chrono::day{29};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool
+operator==(const year_month_day_last& __lhs, const year_month_day_last& __rhs) noexcept {
+ return __lhs.year() == __rhs.year() && __lhs.month_day_last() == __rhs.month_day_last();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering
+operator<=>(const year_month_day_last& __lhs, const year_month_day_last& __rhs) noexcept {
+ if (auto __c = __lhs.year() <=> __rhs.year(); __c != 0)
+ return __c;
+ return __lhs.month_day_last() <=> __rhs.month_day_last();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last operator/(const year_month& __lhs, last_spec) noexcept {
+ return year_month_day_last{__lhs.year(), month_day_last{__lhs.month()}};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last
+operator/(const year& __lhs, const month_day_last& __rhs) noexcept {
+ return year_month_day_last{__lhs, __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last operator/(int __lhs, const month_day_last& __rhs) noexcept {
+ return year_month_day_last{year{__lhs}, __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last
+operator/(const month_day_last& __lhs, const year& __rhs) noexcept {
+ return __rhs / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last operator/(const month_day_last& __lhs, int __rhs) noexcept {
+ return year{__rhs} / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last
+operator+(const year_month_day_last& __lhs, const months& __rhs) noexcept {
+ return (__lhs.year() / __lhs.month() + __rhs) / last;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last
+operator+(const months& __lhs, const year_month_day_last& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last
+operator-(const year_month_day_last& __lhs, const months& __rhs) noexcept {
+ return __lhs + (-__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last
+operator+(const year_month_day_last& __lhs, const years& __rhs) noexcept {
+ return year_month_day_last{__lhs.year() + __rhs, __lhs.month_day_last()};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last
+operator+(const years& __lhs, const year_month_day_last& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last
+operator-(const year_month_day_last& __lhs, const years& __rhs) noexcept {
+ return __lhs + (-__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last&
+year_month_day_last::operator+=(const months& __dm) noexcept {
+ *this = *this + __dm;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last&
+year_month_day_last::operator-=(const months& __dm) noexcept {
+ *this = *this - __dm;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last&
+year_month_day_last::operator+=(const years& __dy) noexcept {
+ *this = *this + __dy;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day_last&
+year_month_day_last::operator-=(const years& __dy) noexcept {
+ *this = *this - __dy;
+ return *this;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_day::year_month_day(const year_month_day_last& __ymdl) noexcept
+ : __y_{__ymdl.year()}, __m_{__ymdl.month()}, __d_{__ymdl.day()} {}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool year_month_day::ok() const noexcept {
+ if (!__y_.ok() || !__m_.ok())
+ return false;
+ return chrono::day{1} <= __d_ && __d_ <= (__y_ / __m_ / last).day();
+}
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_YEAR_MONTH_DAY_H
diff --git a/libcxx/include/__cxx03/__chrono/year_month_weekday.h b/libcxx/include/__cxx03/__chrono/year_month_weekday.h
new file mode 100644
index 00000000000000..0c3dd494c87872
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/year_month_weekday.h
@@ -0,0 +1,287 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CHRONO_YEAR_MONTH_WEEKDAY_H
+#define _LIBCPP___CHRONO_YEAR_MONTH_WEEKDAY_H
+
+#include <__chrono/calendar.h>
+#include <__chrono/day.h>
+#include <__chrono/duration.h>
+#include <__chrono/month.h>
+#include <__chrono/month_weekday.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/time_point.h>
+#include <__chrono/weekday.h>
+#include <__chrono/year.h>
+#include <__chrono/year_month.h>
+#include <__chrono/year_month_day.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace chrono {
+
+class year_month_weekday {
+ chrono::year __y_;
+ chrono::month __m_;
+ chrono::weekday_indexed __wdi_;
+
+public:
+ year_month_weekday() = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday(
+ const chrono::year& __yval, const chrono::month& __mval, const chrono::weekday_indexed& __wdival) noexcept
+ : __y_{__yval}, __m_{__mval}, __wdi_{__wdival} {}
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday(const sys_days& __sysd) noexcept
+ : year_month_weekday(__from_days(__sysd.time_since_epoch())) {}
+ _LIBCPP_HIDE_FROM_ABI inline explicit constexpr year_month_weekday(const local_days& __locd) noexcept
+ : year_month_weekday(__from_days(__locd.time_since_epoch())) {}
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday& operator+=(const months&) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday& operator-=(const months&) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday& operator+=(const years&) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday& operator-=(const years&) noexcept;
+
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::year year() const noexcept { return __y_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::weekday weekday() const noexcept { return __wdi_.weekday(); }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr unsigned index() const noexcept { return __wdi_.index(); }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::weekday_indexed weekday_indexed() const noexcept { return __wdi_; }
+
+ _LIBCPP_HIDE_FROM_ABI inline constexpr operator sys_days() const noexcept { return sys_days{__to_days()}; }
+ _LIBCPP_HIDE_FROM_ABI inline explicit constexpr operator local_days() const noexcept {
+ return local_days{__to_days()};
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept {
+ if (!__y_.ok() || !__m_.ok() || !__wdi_.ok())
+ return false;
+ if (__wdi_.index() <= 4)
+ return true;
+ auto __nth_weekday_day =
+ __wdi_.weekday() - chrono::weekday{static_cast<sys_days>(__y_ / __m_ / 1)} + days{(__wdi_.index() - 1) * 7 + 1};
+ return static_cast<unsigned>(__nth_weekday_day.count()) <= static_cast<unsigned>((__y_ / __m_ / last).day());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr year_month_weekday __from_days(days __d) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr days __to_days() const noexcept;
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday year_month_weekday::__from_days(days __d) noexcept {
+ const sys_days __sysd{__d};
+ const chrono::weekday __wd = chrono::weekday(__sysd);
+ const year_month_day __ymd = year_month_day(__sysd);
+ return year_month_weekday{__ymd.year(), __ymd.month(), __wd[(static_cast<unsigned>(__ymd.day()) - 1) / 7 + 1]};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr days year_month_weekday::__to_days() const noexcept {
+ const sys_days __sysd = sys_days(__y_ / __m_ / 1);
+ return (__sysd + (__wdi_.weekday() - chrono::weekday(__sysd) + days{(__wdi_.index() - 1) * 7})).time_since_epoch();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool
+operator==(const year_month_weekday& __lhs, const year_month_weekday& __rhs) noexcept {
+ return __lhs.year() == __rhs.year() && __lhs.month() == __rhs.month() &&
+ __lhs.weekday_indexed() == __rhs.weekday_indexed();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator/(const year_month& __lhs, const weekday_indexed& __rhs) noexcept {
+ return year_month_weekday{__lhs.year(), __lhs.month(), __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator/(const year& __lhs, const month_weekday& __rhs) noexcept {
+ return year_month_weekday{__lhs, __rhs.month(), __rhs.weekday_indexed()};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday operator/(int __lhs, const month_weekday& __rhs) noexcept {
+ return year(__lhs) / __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator/(const month_weekday& __lhs, const year& __rhs) noexcept {
+ return __rhs / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday operator/(const month_weekday& __lhs, int __rhs) noexcept {
+ return year(__rhs) / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator+(const year_month_weekday& __lhs, const months& __rhs) noexcept {
+ return (__lhs.year() / __lhs.month() + __rhs) / __lhs.weekday_indexed();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator+(const months& __lhs, const year_month_weekday& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator-(const year_month_weekday& __lhs, const months& __rhs) noexcept {
+ return __lhs + (-__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator+(const year_month_weekday& __lhs, const years& __rhs) noexcept {
+ return year_month_weekday{__lhs.year() + __rhs, __lhs.month(), __lhs.weekday_indexed()};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator+(const years& __lhs, const year_month_weekday& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday
+operator-(const year_month_weekday& __lhs, const years& __rhs) noexcept {
+ return __lhs + (-__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday& year_month_weekday::operator+=(const months& __dm) noexcept {
+ *this = *this + __dm;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday& year_month_weekday::operator-=(const months& __dm) noexcept {
+ *this = *this - __dm;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday& year_month_weekday::operator+=(const years& __dy) noexcept {
+ *this = *this + __dy;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday& year_month_weekday::operator-=(const years& __dy) noexcept {
+ *this = *this - __dy;
+ return *this;
+}
+
+class year_month_weekday_last {
+private:
+ chrono::year __y_;
+ chrono::month __m_;
+ chrono::weekday_last __wdl_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday_last(
+ const chrono::year& __yval, const chrono::month& __mval, const chrono::weekday_last& __wdlval) noexcept
+ : __y_{__yval}, __m_{__mval}, __wdl_{__wdlval} {}
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday_last& operator+=(const months& __dm) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday_last& operator-=(const months& __dm) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday_last& operator+=(const years& __dy) noexcept;
+ _LIBCPP_HIDE_FROM_ABI constexpr year_month_weekday_last& operator-=(const years& __dy) noexcept;
+
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::year year() const noexcept { return __y_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::month month() const noexcept { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::weekday weekday() const noexcept { return __wdl_.weekday(); }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::weekday_last weekday_last() const noexcept { return __wdl_; }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr operator sys_days() const noexcept { return sys_days{__to_days()}; }
+ _LIBCPP_HIDE_FROM_ABI inline explicit constexpr operator local_days() const noexcept {
+ return local_days{__to_days()};
+ }
+ _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __y_.ok() && __m_.ok() && __wdl_.ok(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr days __to_days() const noexcept;
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr days year_month_weekday_last::__to_days() const noexcept {
+ const sys_days __last = sys_days{__y_ / __m_ / last};
+ return (__last - (chrono::weekday{__last} - __wdl_.weekday())).time_since_epoch();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool
+operator==(const year_month_weekday_last& __lhs, const year_month_weekday_last& __rhs) noexcept {
+ return __lhs.year() == __rhs.year() && __lhs.month() == __rhs.month() && __lhs.weekday_last() == __rhs.weekday_last();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator/(const year_month& __lhs, const weekday_last& __rhs) noexcept {
+ return year_month_weekday_last{__lhs.year(), __lhs.month(), __rhs};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator/(const year& __lhs, const month_weekday_last& __rhs) noexcept {
+ return year_month_weekday_last{__lhs, __rhs.month(), __rhs.weekday_last()};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator/(int __lhs, const month_weekday_last& __rhs) noexcept {
+ return year(__lhs) / __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator/(const month_weekday_last& __lhs, const year& __rhs) noexcept {
+ return __rhs / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator/(const month_weekday_last& __lhs, int __rhs) noexcept {
+ return year(__rhs) / __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator+(const year_month_weekday_last& __lhs, const months& __rhs) noexcept {
+ return (__lhs.year() / __lhs.month() + __rhs) / __lhs.weekday_last();
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator+(const months& __lhs, const year_month_weekday_last& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator-(const year_month_weekday_last& __lhs, const months& __rhs) noexcept {
+ return __lhs + (-__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator+(const year_month_weekday_last& __lhs, const years& __rhs) noexcept {
+ return year_month_weekday_last{__lhs.year() + __rhs, __lhs.month(), __lhs.weekday_last()};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator+(const years& __lhs, const year_month_weekday_last& __rhs) noexcept {
+ return __rhs + __lhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last
+operator-(const year_month_weekday_last& __lhs, const years& __rhs) noexcept {
+ return __lhs + (-__rhs);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last&
+year_month_weekday_last::operator+=(const months& __dm) noexcept {
+ *this = *this + __dm;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last&
+year_month_weekday_last::operator-=(const months& __dm) noexcept {
+ *this = *this - __dm;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last&
+year_month_weekday_last::operator+=(const years& __dy) noexcept {
+ *this = *this + __dy;
+ return *this;
+}
+_LIBCPP_HIDE_FROM_ABI inline constexpr year_month_weekday_last&
+year_month_weekday_last::operator-=(const years& __dy) noexcept {
+ *this = *this - __dy;
+ return *this;
+}
+
+} // namespace chrono
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___CHRONO_YEAR_MONTH_WEEKDAY_H
diff --git a/libcxx/include/__cxx03/__chrono/zoned_time.h b/libcxx/include/__cxx03/__chrono/zoned_time.h
new file mode 100644
index 00000000000000..8cfa2122642c5e
--- /dev/null
+++ b/libcxx/include/__cxx03/__chrono/zoned_time.h
@@ -0,0 +1,227 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
+
+#ifndef _LIBCPP___CHRONO_ZONED_TIME_H
+#define _LIBCPP___CHRONO_ZONED_TIME_H
+
+#include <version>
+// Enable the contents of the header only when libc++ was built with experimental features enabled.
+#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+# include <__chrono/calendar.h>
+# include <__chrono/duration.h>
+# include <__chrono/sys_info.h>
+# include <__chrono/system_clock.h>
+# include <__chrono/time_zone.h>
+# include <__chrono/tzdb_list.h>
+# include <__config>
+# include <__fwd/string_view.h>
+# include <__type_traits/common_type.h>
+# include <__type_traits/conditional.h>
+# include <__type_traits/remove_cvref.h>
+# include <__utility/move.h>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+namespace chrono {
+
+template <class>
+struct zoned_traits {};
+
+template <>
+struct zoned_traits<const time_zone*> {
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static const time_zone* default_zone() { return chrono::locate_zone("UTC"); }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static const time_zone* locate_zone(string_view __name) {
+ return chrono::locate_zone(__name);
+ }
+};
+
+template <class _Duration, class _TimeZonePtr = const time_zone*>
+class zoned_time {
+ // [time.zone.zonedtime.ctor]/2
+ static_assert(__is_duration<_Duration>::value,
+ "the program is ill-formed since _Duration is not a specialization of std::chrono::duration");
+
+ // The wording uses the constraints like
+ // constructible_from<zoned_time, decltype(__traits::locate_zone(string_view{}))>
+ // Using these constraints in the code causes the compiler to give an
+ // error that the constraint depends on itself. To avoid that issue use
+ // the fact it is possible to create this object from a _TimeZonePtr.
+ using __traits = zoned_traits<_TimeZonePtr>;
+
+public:
+ using duration = common_type_t<_Duration, seconds>;
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time()
+ requires requires { __traits::default_zone(); }
+ : __zone_{__traits::default_zone()}, __tp_{} {}
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time(const zoned_time&) = default;
+ _LIBCPP_HIDE_FROM_ABI zoned_time& operator=(const zoned_time&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time(const sys_time<_Duration>& __tp)
+ requires requires { __traits::default_zone(); }
+ : __zone_{__traits::default_zone()}, __tp_{__tp} {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit zoned_time(_TimeZonePtr __zone) : __zone_{std::move(__zone)}, __tp_{} {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit zoned_time(string_view __name)
+ requires(requires { __traits::locate_zone(string_view{}); } &&
+ constructible_from<_TimeZonePtr, decltype(__traits::locate_zone(string_view{}))>)
+ : __zone_{__traits::locate_zone(__name)}, __tp_{} {}
+
+ template <class _Duration2>
+ _LIBCPP_HIDE_FROM_ABI zoned_time(const zoned_time<_Duration2, _TimeZonePtr>& __zt)
+ requires is_convertible_v<sys_time<_Duration2>, sys_time<_Duration>>
+ : __zone_{__zt.get_time_zone()}, __tp_{__zt.get_sys_time()} {}
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time(_TimeZonePtr __zone, const sys_time<_Duration>& __tp)
+ : __zone_{std::move(__zone)}, __tp_{__tp} {}
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time(string_view __name, const sys_time<_Duration>& __tp)
+ requires requires { _TimeZonePtr{__traits::locate_zone(string_view{})}; }
+ : zoned_time{__traits::locate_zone(__name), __tp} {}
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time(_TimeZonePtr __zone, const local_time<_Duration>& __tp)
+ requires(is_convertible_v<decltype(std::declval<_TimeZonePtr&>() -> to_sys(local_time<_Duration>{})),
+ sys_time<duration>>)
+ : __zone_{std::move(__zone)}, __tp_{__zone_->to_sys(__tp)} {}
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time(string_view __name, const local_time<_Duration>& __tp)
+ requires(requires {
+ _TimeZonePtr{__traits::locate_zone(string_view{})};
+ } && is_convertible_v<decltype(std::declval<_TimeZonePtr&>() -> to_sys(local_time<_Duration>{})),
+ sys_time<duration>>)
+ : zoned_time{__traits::locate_zone(__name), __tp} {}
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time(_TimeZonePtr __zone, const local_time<_Duration>& __tp, choose __c)
+ requires(is_convertible_v<
+ decltype(std::declval<_TimeZonePtr&>() -> to_sys(local_time<_Duration>{}, choose::earliest)),
+ sys_time<duration>>)
+ : __zone_{std::move(__zone)}, __tp_{__zone_->to_sys(__tp, __c)} {}
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time(string_view __name, const local_time<_Duration>& __tp, choose __c)
+ requires(requires {
+ _TimeZonePtr{__traits::locate_zone(string_view{})};
+ } && is_convertible_v<decltype(std::declval<_TimeZonePtr&>() -> to_sys(local_time<_Duration>{}, choose::earliest)),
+ sys_time<duration>>)
+ : zoned_time{__traits::locate_zone(__name), __tp, __c} {}
+
+ template <class _Duration2, class _TimeZonePtr2>
+ _LIBCPP_HIDE_FROM_ABI zoned_time(_TimeZonePtr __zone, const zoned_time<_Duration2, _TimeZonePtr2>& __zt)
+ requires is_convertible_v<sys_time<_Duration2>, sys_time<_Duration>>
+ : __zone_{std::move(__zone)}, __tp_{__zt.get_sys_time()} {}
+
+ // per wording choose has no effect
+ template <class _Duration2, class _TimeZonePtr2>
+ _LIBCPP_HIDE_FROM_ABI zoned_time(_TimeZonePtr __zone, const zoned_time<_Duration2, _TimeZonePtr2>& __zt, choose)
+ requires is_convertible_v<sys_time<_Duration2>, sys_time<_Duration>>
+ : __zone_{std::move(__zone)}, __tp_{__zt.get_sys_time()} {}
+
+ template <class _Duration2, class _TimeZonePtr2>
+ _LIBCPP_HIDE_FROM_ABI zoned_time(string_view __name, const zoned_time<_Duration2, _TimeZonePtr2>& __zt)
+ requires(requires {
+ _TimeZonePtr{__traits::locate_zone(string_view{})};
+ } && is_convertible_v<sys_time<_Duration2>, sys_time<_Duration>>)
+ : zoned_time{__traits::locate_zone(__name), __zt} {}
+
+ template <class _Duration2, class _TimeZonePtr2>
+ _LIBCPP_HIDE_FROM_ABI zoned_time(string_view __name, const zoned_time<_Duration2, _TimeZonePtr2>& __zt, choose __c)
+ requires(requires {
+ _TimeZonePtr{__traits::locate_zone(string_view{})};
+ } && is_convertible_v<sys_time<_Duration2>, sys_time<_Duration>>)
+ : zoned_time{__traits::locate_zone(__name), __zt, __c} {}
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time& operator=(const sys_time<_Duration>& __tp) {
+ __tp_ = __tp;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI zoned_time& operator=(const local_time<_Duration>& __tp) {
+ // TODO TZDB This seems wrong.
+ // Assigning a non-existent or ambiguous time will throw and not satisfy
+ // the post condition. This seems quite odd; I constructed an object with
+ // choose::earliest and that choice is not respected.
+ // what did LEWG do with this.
+ // MSVC STL and libstdc++ behave the same
+ __tp_ = __zone_->to_sys(__tp);
+ return *this;
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI operator sys_time<duration>() const { return get_sys_time(); }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI explicit operator local_time<duration>() const { return get_local_time(); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI _TimeZonePtr get_time_zone() const { return __zone_; }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI local_time<duration> get_local_time() const { return __zone_->to_local(__tp_); }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI sys_time<duration> get_sys_time() const { return __tp_; }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI sys_info get_info() const { return __zone_->get_info(__tp_); }
+
+private:
+ _TimeZonePtr __zone_;
+ sys_time<duration> __tp_;
+};
+
+zoned_time() -> zoned_time<seconds>;
+
+template <class _Duration>
+zoned_time(sys_time<_Duration>) -> zoned_time<common_type_t<_Duration, seconds>>;
+
+template <class _TimeZonePtrOrName>
+using __time_zone_representation =
+ conditional_t<is_convertible_v<_TimeZonePtrOrName, string_view>,
+ const time_zone*,
+ remove_cvref_t<_TimeZonePtrOrName>>;
+
+template <class _TimeZonePtrOrName>
+zoned_time(_TimeZonePtrOrName&&) -> zoned_time<seconds, __time_zone_representation<_TimeZonePtrOrName>>;
+
+template <class _TimeZonePtrOrName, class _Duration>
+zoned_time(_TimeZonePtrOrName&&, sys_time<_Duration>)
+ -> zoned_time<common_type_t<_Duration, seconds>, __time_zone_representation<_TimeZonePtrOrName>>;
+
+template <class _TimeZonePtrOrName, class _Duration>
+zoned_time(_TimeZonePtrOrName&&, local_time<_Duration>, choose = choose::earliest)
+ -> zoned_time<common_type_t<_Duration, seconds>, __time_zone_representation<_TimeZonePtrOrName>>;
+
+template <class _Duration, class _TimeZonePtrOrName, class TimeZonePtr2>
+zoned_time(_TimeZonePtrOrName&&, zoned_time<_Duration, TimeZonePtr2>, choose = choose::earliest)
+ -> zoned_time<common_type_t<_Duration, seconds>, __time_zone_representation<_TimeZonePtrOrName>>;
+
+using zoned_seconds = zoned_time<seconds>;
+
+template <class _Duration1, class _Duration2, class _TimeZonePtr>
+_LIBCPP_HIDE_FROM_ABI bool
+operator==(const zoned_time<_Duration1, _TimeZonePtr>& __lhs, const zoned_time<_Duration2, _TimeZonePtr>& __rhs) {
+ return __lhs.get_time_zone() == __rhs.get_time_zone() && __lhs.get_sys_time() == __rhs.get_sys_time();
+}
+
+} // namespace chrono
+
+# endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+ // && !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
+
+#endif // _LIBCPP___CHRONO_ZONED_TIME_H
diff --git a/libcxx/include/__cxx03/__compare/common_comparison_category.h b/libcxx/include/__cxx03/__compare/common_comparison_category.h
new file mode 100644
index 00000000000000..7aeb3da03a4f4a
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/common_comparison_category.h
@@ -0,0 +1,86 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_COMMON_COMPARISON_CATEGORY_H
+#define _LIBCPP___COMPARE_COMMON_COMPARISON_CATEGORY_H
+
+#include <__compare/ordering.h>
+#include <__config>
+#include <__type_traits/is_same.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __comp_detail {
+
+enum _ClassifyCompCategory : unsigned { _None, _PartialOrd, _WeakOrd, _StrongOrd, _CCC_Size };
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _ClassifyCompCategory __type_to_enum() noexcept {
+ if (is_same_v<_Tp, partial_ordering>)
+ return _PartialOrd;
+ if (is_same_v<_Tp, weak_ordering>)
+ return _WeakOrd;
+ if (is_same_v<_Tp, strong_ordering>)
+ return _StrongOrd;
+ return _None;
+}
+
+template <size_t _Size>
+_LIBCPP_HIDE_FROM_ABI constexpr _ClassifyCompCategory
+__compute_comp_type(const _ClassifyCompCategory (&__types)[_Size]) {
+ int __seen[_CCC_Size] = {};
+ for (auto __type : __types)
+ ++__seen[__type];
+ if (__seen[_None])
+ return _None;
+ if (__seen[_PartialOrd])
+ return _PartialOrd;
+ if (__seen[_WeakOrd])
+ return _WeakOrd;
+ return _StrongOrd;
+}
+
+template <class... _Ts, bool _False = false>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __get_comp_type() {
+ using _CCC = _ClassifyCompCategory;
+ constexpr _CCC __type_kinds[] = {_StrongOrd, __type_to_enum<_Ts>()...};
+ constexpr _CCC __cat = __comp_detail::__compute_comp_type(__type_kinds);
+ if constexpr (__cat == _None)
+ return void();
+ else if constexpr (__cat == _PartialOrd)
+ return partial_ordering::equivalent;
+ else if constexpr (__cat == _WeakOrd)
+ return weak_ordering::equivalent;
+ else if constexpr (__cat == _StrongOrd)
+ return strong_ordering::equivalent;
+ else
+ static_assert(_False, "unhandled case");
+}
+} // namespace __comp_detail
+
+// [cmp.common], common comparison category type
+template <class... _Ts>
+struct _LIBCPP_TEMPLATE_VIS common_comparison_category {
+ using type = decltype(__comp_detail::__get_comp_type<_Ts...>());
+};
+
+template <class... _Ts>
+using common_comparison_category_t = typename common_comparison_category<_Ts...>::type;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_COMMON_COMPARISON_CATEGORY_H
diff --git a/libcxx/include/__cxx03/__compare/compare_partial_order_fallback.h b/libcxx/include/__cxx03/__compare/compare_partial_order_fallback.h
new file mode 100644
index 00000000000000..e0efa3ccb88db7
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/compare_partial_order_fallback.h
@@ -0,0 +1,76 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_COMPARE_PARTIAL_ORDER_FALLBACK
+#define _LIBCPP___COMPARE_COMPARE_PARTIAL_ORDER_FALLBACK
+
+#include <__compare/ordering.h>
+#include <__compare/partial_order.h>
+#include <__config>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_same.h>
+#include <__utility/forward.h>
+#include <__utility/priority_tag.h>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [cmp.alg]
+namespace __compare_partial_order_fallback {
+struct __fn {
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<1>) noexcept(
+ noexcept(std::partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))))
+ -> decltype(std::partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))) {
+ return std::partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u));
+ }
+
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<0>) noexcept(noexcept(
+ std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? partial_ordering::equivalent
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u) ? partial_ordering::less
+ : std::forward<_Up>(__u) < std::forward<_Tp>(__t)
+ ? partial_ordering::greater
+ : partial_ordering::unordered))
+ -> decltype(std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? partial_ordering::equivalent
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u) ? partial_ordering::less
+ : std::forward<_Up>(__u) < std::forward<_Tp>(__t)
+ ? partial_ordering::greater
+ : partial_ordering::unordered) {
+ return std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? partial_ordering::equivalent
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u) ? partial_ordering::less
+ : std::forward<_Up>(__u) < std::forward<_Tp>(__t)
+ ? partial_ordering::greater
+ : partial_ordering::unordered;
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>())))
+ -> decltype(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>())) {
+ return __go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>());
+ }
+};
+} // namespace __compare_partial_order_fallback
+
+inline namespace __cpo {
+inline constexpr auto compare_partial_order_fallback = __compare_partial_order_fallback::__fn{};
+} // namespace __cpo
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_COMPARE_PARTIAL_ORDER_FALLBACK
diff --git a/libcxx/include/__cxx03/__compare/compare_strong_order_fallback.h b/libcxx/include/__cxx03/__compare/compare_strong_order_fallback.h
new file mode 100644
index 00000000000000..a94d517ed30fce
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/compare_strong_order_fallback.h
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_COMPARE_STRONG_ORDER_FALLBACK
+#define _LIBCPP___COMPARE_COMPARE_STRONG_ORDER_FALLBACK
+
+#include <__compare/ordering.h>
+#include <__compare/strong_order.h>
+#include <__config>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_same.h>
+#include <__utility/forward.h>
+#include <__utility/priority_tag.h>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [cmp.alg]
+namespace __compare_strong_order_fallback {
+struct __fn {
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<1>) noexcept(
+ noexcept(std::strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))))
+ -> decltype(std::strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))) {
+ return std::strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u));
+ }
+
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<0>) noexcept(noexcept(
+ std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? strong_ordering::equal
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u)
+ ? strong_ordering::less
+ : strong_ordering::greater))
+ -> decltype(std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? strong_ordering::equal
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u)
+ ? strong_ordering::less
+ : strong_ordering::greater) {
+ return std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? strong_ordering::equal
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u)
+ ? strong_ordering::less
+ : strong_ordering::greater;
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>())))
+ -> decltype(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>())) {
+ return __go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>());
+ }
+};
+} // namespace __compare_strong_order_fallback
+
+inline namespace __cpo {
+inline constexpr auto compare_strong_order_fallback = __compare_strong_order_fallback::__fn{};
+} // namespace __cpo
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_COMPARE_STRONG_ORDER_FALLBACK
diff --git a/libcxx/include/__cxx03/__compare/compare_three_way.h b/libcxx/include/__cxx03/__compare/compare_three_way.h
new file mode 100644
index 00000000000000..01c12076c0d73d
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/compare_three_way.h
@@ -0,0 +1,40 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_COMPARE_THREE_WAY_H
+#define _LIBCPP___COMPARE_COMPARE_THREE_WAY_H
+
+#include <__compare/three_way_comparable.h>
+#include <__config>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+struct _LIBCPP_TEMPLATE_VIS compare_three_way {
+ template <class _T1, class _T2>
+ requires three_way_comparable_with<_T1, _T2>
+ constexpr _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) <=> std::forward<_T2>(__u))) {
+ return std::forward<_T1>(__t) <=> std::forward<_T2>(__u);
+ }
+
+ using is_transparent = void;
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_COMPARE_THREE_WAY_H
diff --git a/libcxx/include/__cxx03/__compare/compare_three_way_result.h b/libcxx/include/__cxx03/__compare/compare_three_way_result.h
new file mode 100644
index 00000000000000..d7508073433af4
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/compare_three_way_result.h
@@ -0,0 +1,45 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_COMPARE_THREE_WAY_RESULT_H
+#define _LIBCPP___COMPARE_COMPARE_THREE_WAY_RESULT_H
+
+#include <__config>
+#include <__type_traits/make_const_lvalue_ref.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class, class, class>
+struct _LIBCPP_HIDE_FROM_ABI __compare_three_way_result {};
+
+template <class _Tp, class _Up>
+struct _LIBCPP_HIDE_FROM_ABI __compare_three_way_result<
+ _Tp,
+ _Up,
+ decltype(std::declval<__make_const_lvalue_ref<_Tp>>() <=> std::declval<__make_const_lvalue_ref<_Up>>(), void())> {
+ using type = decltype(std::declval<__make_const_lvalue_ref<_Tp>>() <=> std::declval<__make_const_lvalue_ref<_Up>>());
+};
+
+template <class _Tp, class _Up = _Tp>
+struct _LIBCPP_TEMPLATE_VIS compare_three_way_result : __compare_three_way_result<_Tp, _Up, void> {};
+
+template <class _Tp, class _Up = _Tp>
+using compare_three_way_result_t = typename compare_three_way_result<_Tp, _Up>::type;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_COMPARE_THREE_WAY_RESULT_H
diff --git a/libcxx/include/__cxx03/__compare/compare_weak_order_fallback.h b/libcxx/include/__cxx03/__compare/compare_weak_order_fallback.h
new file mode 100644
index 00000000000000..062b7b582cd7eb
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/compare_weak_order_fallback.h
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_COMPARE_WEAK_ORDER_FALLBACK
+#define _LIBCPP___COMPARE_COMPARE_WEAK_ORDER_FALLBACK
+
+#include <__compare/ordering.h>
+#include <__compare/weak_order.h>
+#include <__config>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_same.h>
+#include <__utility/forward.h>
+#include <__utility/priority_tag.h>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [cmp.alg]
+namespace __compare_weak_order_fallback {
+struct __fn {
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<1>) noexcept(
+ noexcept(std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))))
+ -> decltype(std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))) {
+ return std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u));
+ }
+
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<0>) noexcept(noexcept(
+ std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? weak_ordering::equivalent
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u)
+ ? weak_ordering::less
+ : weak_ordering::greater))
+ -> decltype(std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? weak_ordering::equivalent
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u)
+ ? weak_ordering::less
+ : weak_ordering::greater) {
+ return std::forward<_Tp>(__t) == std::forward<_Up>(__u) ? weak_ordering::equivalent
+ : std::forward<_Tp>(__t) < std::forward<_Up>(__u)
+ ? weak_ordering::less
+ : weak_ordering::greater;
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>())))
+ -> decltype(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>())) {
+ return __go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<1>());
+ }
+};
+} // namespace __compare_weak_order_fallback
+
+inline namespace __cpo {
+inline constexpr auto compare_weak_order_fallback = __compare_weak_order_fallback::__fn{};
+} // namespace __cpo
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_COMPARE_WEAK_ORDER_FALLBACK
diff --git a/libcxx/include/__cxx03/__compare/is_eq.h b/libcxx/include/__cxx03/__compare/is_eq.h
new file mode 100644
index 00000000000000..9a82df1ebe88b7
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/is_eq.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_IS_EQ_H
+#define _LIBCPP___COMPARE_IS_EQ_H
+
+#include <__compare/ordering.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_eq(partial_ordering __c) noexcept { return __c == 0; }
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_neq(partial_ordering __c) noexcept { return __c != 0; }
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_lt(partial_ordering __c) noexcept { return __c < 0; }
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_lteq(partial_ordering __c) noexcept { return __c <= 0; }
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_gt(partial_ordering __c) noexcept { return __c > 0; }
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_gteq(partial_ordering __c) noexcept { return __c >= 0; }
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_IS_EQ_H
diff --git a/libcxx/include/__cxx03/__compare/ordering.h b/libcxx/include/__cxx03/__compare/ordering.h
new file mode 100644
index 00000000000000..2995d381304f0e
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/ordering.h
@@ -0,0 +1,278 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_ORDERING_H
+#define _LIBCPP___COMPARE_ORDERING_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_same.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// exposition only
+enum class _OrdResult : signed char { __less = -1, __equiv = 0, __greater = 1 };
+
+enum class _NCmpResult : signed char { __unordered = -127 };
+
+class partial_ordering;
+class weak_ordering;
+class strong_ordering;
+
+template <class _Tp, class... _Args>
+inline constexpr bool __one_of_v = (is_same_v<_Tp, _Args> || ...);
+
+struct _CmpUnspecifiedParam {
+ _LIBCPP_HIDE_FROM_ABI constexpr _CmpUnspecifiedParam(int _CmpUnspecifiedParam::*) noexcept {}
+
+ template <class _Tp, class = enable_if_t<!__one_of_v<_Tp, int, partial_ordering, weak_ordering, strong_ordering>>>
+ _CmpUnspecifiedParam(_Tp) = delete;
+};
+
+class partial_ordering {
+ using _ValueT = signed char;
+
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr partial_ordering(_OrdResult __v) noexcept : __value_(_ValueT(__v)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr partial_ordering(_NCmpResult __v) noexcept : __value_(_ValueT(__v)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __is_ordered() const noexcept {
+ return __value_ != _ValueT(_NCmpResult::__unordered);
+ }
+
+public:
+ // valid values
+ static const partial_ordering less;
+ static const partial_ordering equivalent;
+ static const partial_ordering greater;
+ static const partial_ordering unordered;
+
+ // comparisons
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(partial_ordering, partial_ordering) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(partial_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__is_ordered() && __v.__value_ == 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(partial_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__is_ordered() && __v.__value_ < 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(partial_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__is_ordered() && __v.__value_ <= 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(partial_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__is_ordered() && __v.__value_ > 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(partial_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__is_ordered() && __v.__value_ >= 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(_CmpUnspecifiedParam, partial_ordering __v) noexcept {
+ return __v.__is_ordered() && 0 < __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(_CmpUnspecifiedParam, partial_ordering __v) noexcept {
+ return __v.__is_ordered() && 0 <= __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(_CmpUnspecifiedParam, partial_ordering __v) noexcept {
+ return __v.__is_ordered() && 0 > __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(_CmpUnspecifiedParam, partial_ordering __v) noexcept {
+ return __v.__is_ordered() && 0 >= __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr partial_ordering
+ operator<=>(partial_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr partial_ordering
+ operator<=>(_CmpUnspecifiedParam, partial_ordering __v) noexcept {
+ return __v < 0 ? partial_ordering::greater : (__v > 0 ? partial_ordering::less : __v);
+ }
+
+private:
+ _ValueT __value_;
+};
+
+inline constexpr partial_ordering partial_ordering::less(_OrdResult::__less);
+inline constexpr partial_ordering partial_ordering::equivalent(_OrdResult::__equiv);
+inline constexpr partial_ordering partial_ordering::greater(_OrdResult::__greater);
+inline constexpr partial_ordering partial_ordering::unordered(_NCmpResult ::__unordered);
+
+class weak_ordering {
+ using _ValueT = signed char;
+
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr weak_ordering(_OrdResult __v) noexcept : __value_(_ValueT(__v)) {}
+
+public:
+ static const weak_ordering less;
+ static const weak_ordering equivalent;
+ static const weak_ordering greater;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr operator partial_ordering() const noexcept {
+ return __value_ == 0 ? partial_ordering::equivalent
+ : (__value_ < 0 ? partial_ordering::less : partial_ordering::greater);
+ }
+
+ // comparisons
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(weak_ordering, weak_ordering) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(weak_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ == 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(weak_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ < 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(weak_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ <= 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(weak_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ > 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(weak_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ >= 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(_CmpUnspecifiedParam, weak_ordering __v) noexcept {
+ return 0 < __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(_CmpUnspecifiedParam, weak_ordering __v) noexcept {
+ return 0 <= __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(_CmpUnspecifiedParam, weak_ordering __v) noexcept {
+ return 0 > __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(_CmpUnspecifiedParam, weak_ordering __v) noexcept {
+ return 0 >= __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr weak_ordering operator<=>(weak_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr weak_ordering operator<=>(_CmpUnspecifiedParam, weak_ordering __v) noexcept {
+ return __v < 0 ? weak_ordering::greater : (__v > 0 ? weak_ordering::less : __v);
+ }
+
+private:
+ _ValueT __value_;
+};
+
+inline constexpr weak_ordering weak_ordering::less(_OrdResult::__less);
+inline constexpr weak_ordering weak_ordering::equivalent(_OrdResult::__equiv);
+inline constexpr weak_ordering weak_ordering::greater(_OrdResult::__greater);
+
+class strong_ordering {
+ using _ValueT = signed char;
+
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr strong_ordering(_OrdResult __v) noexcept : __value_(_ValueT(__v)) {}
+
+public:
+ static const strong_ordering less;
+ static const strong_ordering equal;
+ static const strong_ordering equivalent;
+ static const strong_ordering greater;
+
+ // conversions
+ _LIBCPP_HIDE_FROM_ABI constexpr operator partial_ordering() const noexcept {
+ return __value_ == 0 ? partial_ordering::equivalent
+ : (__value_ < 0 ? partial_ordering::less : partial_ordering::greater);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr operator weak_ordering() const noexcept {
+ return __value_ == 0 ? weak_ordering::equivalent : (__value_ < 0 ? weak_ordering::less : weak_ordering::greater);
+ }
+
+ // comparisons
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(strong_ordering, strong_ordering) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(strong_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ == 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(strong_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ < 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(strong_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ <= 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(strong_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ > 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(strong_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v.__value_ >= 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(_CmpUnspecifiedParam, strong_ordering __v) noexcept {
+ return 0 < __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(_CmpUnspecifiedParam, strong_ordering __v) noexcept {
+ return 0 <= __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(_CmpUnspecifiedParam, strong_ordering __v) noexcept {
+ return 0 > __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(_CmpUnspecifiedParam, strong_ordering __v) noexcept {
+ return 0 >= __v.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr strong_ordering
+ operator<=>(strong_ordering __v, _CmpUnspecifiedParam) noexcept {
+ return __v;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr strong_ordering
+ operator<=>(_CmpUnspecifiedParam, strong_ordering __v) noexcept {
+ return __v < 0 ? strong_ordering::greater : (__v > 0 ? strong_ordering::less : __v);
+ }
+
+private:
+ _ValueT __value_;
+};
+
+inline constexpr strong_ordering strong_ordering::less(_OrdResult::__less);
+inline constexpr strong_ordering strong_ordering::equal(_OrdResult::__equiv);
+inline constexpr strong_ordering strong_ordering::equivalent(_OrdResult::__equiv);
+inline constexpr strong_ordering strong_ordering::greater(_OrdResult::__greater);
+
+/// [cmp.categories.pre]/1
+/// The types partial_ordering, weak_ordering, and strong_ordering are
+/// collectively termed the comparison category types.
+template <class _Tp>
+concept __comparison_category = __one_of_v<_Tp, partial_ordering, weak_ordering, strong_ordering>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_ORDERING_H
diff --git a/libcxx/include/__cxx03/__compare/partial_order.h b/libcxx/include/__cxx03/__compare/partial_order.h
new file mode 100644
index 00000000000000..1d2fae63e5f248
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/partial_order.h
@@ -0,0 +1,77 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_PARTIAL_ORDER
+#define _LIBCPP___COMPARE_PARTIAL_ORDER
+
+#include <__compare/compare_three_way.h>
+#include <__compare/ordering.h>
+#include <__compare/weak_order.h>
+#include <__config>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_same.h>
+#include <__utility/forward.h>
+#include <__utility/priority_tag.h>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [cmp.alg]
+namespace __partial_order {
+void partial_order() = delete;
+
+struct __fn {
+ // NOLINTBEGIN(libcpp-robust-against-adl) partial_order should use ADL, but only here
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<2>) noexcept(
+ noexcept(partial_ordering(partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))))
+ -> decltype(partial_ordering(partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ return partial_ordering(partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)));
+ }
+ // NOLINTEND(libcpp-robust-against-adl)
+
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<1>) noexcept(
+ noexcept(partial_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)))))
+ -> decltype(partial_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ return partial_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)));
+ }
+
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<0>) noexcept(
+ noexcept(partial_ordering(std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))))
+ -> decltype(partial_ordering(std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ return partial_ordering(std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)));
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>())))
+ -> decltype(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>())) {
+ return __go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>());
+ }
+};
+} // namespace __partial_order
+
+inline namespace __cpo {
+inline constexpr auto partial_order = __partial_order::__fn{};
+} // namespace __cpo
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_PARTIAL_ORDER
diff --git a/libcxx/include/__cxx03/__compare/strong_order.h b/libcxx/include/__cxx03/__compare/strong_order.h
new file mode 100644
index 00000000000000..8c363b56382221
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/strong_order.h
@@ -0,0 +1,143 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_STRONG_ORDER
+#define _LIBCPP___COMPARE_STRONG_ORDER
+
+#include <__bit/bit_cast.h>
+#include <__compare/compare_three_way.h>
+#include <__compare/ordering.h>
+#include <__config>
+#include <__math/exponential_functions.h>
+#include <__math/traits.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_same.h>
+#include <__utility/forward.h>
+#include <__utility/priority_tag.h>
+#include <cstdint>
+#include <limits>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [cmp.alg]
+namespace __strong_order {
+void strong_order() = delete;
+
+struct __fn {
+ // NOLINTBEGIN(libcpp-robust-against-adl) strong_order should use ADL, but only here
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<2>) noexcept(
+ noexcept(strong_ordering(strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))))
+ -> decltype(strong_ordering(strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ return strong_ordering(strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)));
+ }
+ // NOLINTEND(libcpp-robust-against-adl)
+
+ template <class _Tp, class _Up, class _Dp = decay_t<_Tp>>
+ requires is_same_v<_Dp, decay_t<_Up>> && is_floating_point_v<_Dp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr strong_ordering __go(_Tp&& __t, _Up&& __u, __priority_tag<1>) noexcept {
+ if constexpr (numeric_limits<_Dp>::is_iec559 && sizeof(_Dp) == sizeof(int32_t)) {
+ int32_t __rx = std::bit_cast<int32_t>(__t);
+ int32_t __ry = std::bit_cast<int32_t>(__u);
+ __rx = (__rx < 0) ? (numeric_limits<int32_t>::min() - __rx - 1) : __rx;
+ __ry = (__ry < 0) ? (numeric_limits<int32_t>::min() - __ry - 1) : __ry;
+ return (__rx <=> __ry);
+ } else if constexpr (numeric_limits<_Dp>::is_iec559 && sizeof(_Dp) == sizeof(int64_t)) {
+ int64_t __rx = std::bit_cast<int64_t>(__t);
+ int64_t __ry = std::bit_cast<int64_t>(__u);
+ __rx = (__rx < 0) ? (numeric_limits<int64_t>::min() - __rx - 1) : __rx;
+ __ry = (__ry < 0) ? (numeric_limits<int64_t>::min() - __ry - 1) : __ry;
+ return (__rx <=> __ry);
+ } else if (__t < __u) {
+ return strong_ordering::less;
+ } else if (__t > __u) {
+ return strong_ordering::greater;
+ } else if (__t == __u) {
+ if constexpr (numeric_limits<_Dp>::radix == 2) {
+ return __math::signbit(__u) <=> __math::signbit(__t);
+ } else {
+ // This is bullet 3 of the IEEE754 algorithm, relevant
+ // only for decimal floating-point;
+ // see https://stackoverflow.com/questions/69068075/
+ if (__t == 0 || __math::isinf(__t)) {
+ return __math::signbit(__u) <=> __math::signbit(__t);
+ } else {
+ int __texp, __uexp;
+ (void)__math::frexp(__t, &__texp);
+ (void)__math::frexp(__u, &__uexp);
+ return (__t < 0) ? (__texp <=> __uexp) : (__uexp <=> __texp);
+ }
+ }
+ } else {
+ // They're unordered, so one of them must be a NAN.
+ // The order is -QNAN, -SNAN, numbers, +SNAN, +QNAN.
+ bool __t_is_nan = __math::isnan(__t);
+ bool __u_is_nan = __math::isnan(__u);
+ bool __t_is_negative = __math::signbit(__t);
+ bool __u_is_negative = __math::signbit(__u);
+ using _IntType =
+ conditional_t< sizeof(__t) == sizeof(int32_t),
+ int32_t,
+ conditional_t< sizeof(__t) == sizeof(int64_t), int64_t, void> >;
+ if constexpr (is_same_v<_IntType, void>) {
+ static_assert(sizeof(_Dp) == 0, "std::strong_order is unimplemented for this floating-point type");
+ } else if (__t_is_nan && __u_is_nan) {
+ // Order by sign bit, then by "payload bits" (we'll just use bit_cast).
+ if (__t_is_negative != __u_is_negative) {
+ return (__u_is_negative <=> __t_is_negative);
+ } else {
+ return std::bit_cast<_IntType>(__t) <=> std::bit_cast<_IntType>(__u);
+ }
+ } else if (__t_is_nan) {
+ return __t_is_negative ? strong_ordering::less : strong_ordering::greater;
+ } else {
+ return __u_is_negative ? strong_ordering::greater : strong_ordering::less;
+ }
+ }
+ }
+
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<0>) noexcept(
+ noexcept(strong_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)))))
+ -> decltype(strong_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ return strong_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)));
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>())))
+ -> decltype(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>())) {
+ return __go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>());
+ }
+};
+} // namespace __strong_order
+
+inline namespace __cpo {
+inline constexpr auto strong_order = __strong_order::__fn{};
+} // namespace __cpo
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___COMPARE_STRONG_ORDER
diff --git a/libcxx/include/__cxx03/__compare/synth_three_way.h b/libcxx/include/__cxx03/__compare/synth_three_way.h
new file mode 100644
index 00000000000000..e48ce497998368
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/synth_three_way.h
@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_SYNTH_THREE_WAY_H
+#define _LIBCPP___COMPARE_SYNTH_THREE_WAY_H
+
+#include <__compare/ordering.h>
+#include <__compare/three_way_comparable.h>
+#include <__concepts/boolean_testable.h>
+#include <__config>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [expos.only.func]
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr auto __synth_three_way = []<class _Tp, class _Up>(const _Tp& __t, const _Up& __u)
+ requires requires {
+ { __t < __u } -> __boolean_testable;
+ { __u < __t } -> __boolean_testable;
+ }
+{
+ if constexpr (three_way_comparable_with<_Tp, _Up>) {
+ return __t <=> __u;
+ } else {
+ if (__t < __u)
+ return weak_ordering::less;
+ if (__u < __t)
+ return weak_ordering::greater;
+ return weak_ordering::equivalent;
+ }
+};
+
+template <class _Tp, class _Up = _Tp>
+using __synth_three_way_result = decltype(std::__synth_three_way(std::declval<_Tp&>(), std::declval<_Up&>()));
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_SYNTH_THREE_WAY_H
diff --git a/libcxx/include/__cxx03/__compare/three_way_comparable.h b/libcxx/include/__cxx03/__compare/three_way_comparable.h
new file mode 100644
index 00000000000000..7a44ea9158a6f7
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/three_way_comparable.h
@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_THREE_WAY_COMPARABLE_H
+#define _LIBCPP___COMPARE_THREE_WAY_COMPARABLE_H
+
+#include <__compare/common_comparison_category.h>
+#include <__compare/ordering.h>
+#include <__concepts/common_reference_with.h>
+#include <__concepts/equality_comparable.h>
+#include <__concepts/same_as.h>
+#include <__concepts/totally_ordered.h>
+#include <__config>
+#include <__type_traits/common_reference.h>
+#include <__type_traits/make_const_lvalue_ref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp, class _Cat>
+concept __compares_as = same_as<common_comparison_category_t<_Tp, _Cat>, _Cat>;
+
+template <class _Tp, class _Cat = partial_ordering>
+concept three_way_comparable =
+ __weakly_equality_comparable_with<_Tp, _Tp> && __partially_ordered_with<_Tp, _Tp> &&
+ requires(__make_const_lvalue_ref<_Tp> __a, __make_const_lvalue_ref<_Tp> __b) {
+ { __a <=> __b } -> __compares_as<_Cat>;
+ };
+
+template <class _Tp, class _Up, class _Cat = partial_ordering>
+concept three_way_comparable_with =
+ three_way_comparable<_Tp, _Cat> && three_way_comparable<_Up, _Cat> &&
+ common_reference_with<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>> &&
+ three_way_comparable<common_reference_t<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>>, _Cat> &&
+ __weakly_equality_comparable_with<_Tp, _Up> && __partially_ordered_with<_Tp, _Up> &&
+ requires(__make_const_lvalue_ref<_Tp> __t, __make_const_lvalue_ref<_Up> __u) {
+ { __t <=> __u } -> __compares_as<_Cat>;
+ { __u <=> __t } -> __compares_as<_Cat>;
+ };
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_THREE_WAY_COMPARABLE_H
diff --git a/libcxx/include/__cxx03/__compare/weak_order.h b/libcxx/include/__cxx03/__compare/weak_order.h
new file mode 100644
index 00000000000000..1a3e85feb233b3
--- /dev/null
+++ b/libcxx/include/__cxx03/__compare/weak_order.h
@@ -0,0 +1,105 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COMPARE_WEAK_ORDER
+#define _LIBCPP___COMPARE_WEAK_ORDER
+
+#include <__compare/compare_three_way.h>
+#include <__compare/ordering.h>
+#include <__compare/strong_order.h>
+#include <__config>
+#include <__math/traits.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_same.h>
+#include <__utility/forward.h>
+#include <__utility/priority_tag.h>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [cmp.alg]
+namespace __weak_order {
+void weak_order() = delete;
+
+struct __fn {
+ // NOLINTBEGIN(libcpp-robust-against-adl) weak_order should use ADL, but only here
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<3>) noexcept(
+ noexcept(weak_ordering(weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))))
+ -> decltype(weak_ordering(weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ return weak_ordering(weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)));
+ }
+ // NOLINTEND(libcpp-robust-against-adl)
+
+ template <class _Tp, class _Up, class _Dp = decay_t<_Tp>>
+ requires is_same_v<_Dp, decay_t<_Up>> && is_floating_point_v<_Dp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr weak_ordering __go(_Tp&& __t, _Up&& __u, __priority_tag<2>) noexcept {
+ partial_ordering __po = (__t <=> __u);
+ if (__po == partial_ordering::less) {
+ return weak_ordering::less;
+ } else if (__po == partial_ordering::equivalent) {
+ return weak_ordering::equivalent;
+ } else if (__po == partial_ordering::greater) {
+ return weak_ordering::greater;
+ } else {
+ // Otherwise, at least one of them is a NaN.
+ bool __t_is_nan = __math::isnan(__t);
+ bool __u_is_nan = __math::isnan(__u);
+ bool __t_is_negative = __math::signbit(__t);
+ bool __u_is_negative = __math::signbit(__u);
+ if (__t_is_nan && __u_is_nan) {
+ return (__u_is_negative <=> __t_is_negative);
+ } else if (__t_is_nan) {
+ return __t_is_negative ? weak_ordering::less : weak_ordering::greater;
+ } else {
+ return __u_is_negative ? weak_ordering::greater : weak_ordering::less;
+ }
+ }
+ }
+
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<1>) noexcept(
+ noexcept(weak_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)))))
+ -> decltype(weak_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ return weak_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)));
+ }
+
+ template <class _Tp, class _Up>
+ requires is_same_v<decay_t<_Tp>, decay_t<_Up>>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<0>) noexcept(
+ noexcept(weak_ordering(std::strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))))
+ -> decltype(weak_ordering(std::strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ return weak_ordering(std::strong_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)));
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<3>())))
+ -> decltype(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<3>())) {
+ return __go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<3>());
+ }
+};
+} // namespace __weak_order
+
+inline namespace __cpo {
+inline constexpr auto weak_order = __weak_order::__fn{};
+} // namespace __cpo
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___COMPARE_WEAK_ORDER
diff --git a/libcxx/include/__cxx03/__concepts/arithmetic.h b/libcxx/include/__cxx03/__concepts/arithmetic.h
new file mode 100644
index 00000000000000..0c44f117805f36
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/arithmetic.h
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_ARITHMETIC_H
+#define _LIBCPP___CONCEPTS_ARITHMETIC_H
+
+#include <__config>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/is_signed_integer.h>
+#include <__type_traits/is_unsigned_integer.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concepts.arithmetic], arithmetic concepts
+
+template <class _Tp>
+concept integral = is_integral_v<_Tp>;
+
+template <class _Tp>
+concept signed_integral = integral<_Tp> && is_signed_v<_Tp>;
+
+template <class _Tp>
+concept unsigned_integral = integral<_Tp> && !signed_integral<_Tp>;
+
+template <class _Tp>
+concept floating_point = is_floating_point_v<_Tp>;
+
+// Concept helpers for the internal type traits for the fundamental types.
+
+template <class _Tp>
+concept __libcpp_unsigned_integer = __libcpp_is_unsigned_integer<_Tp>::value;
+
+template <class _Tp>
+concept __libcpp_signed_integer = __libcpp_is_signed_integer<_Tp>::value;
+
+template <class _Tp>
+concept __libcpp_integer = __libcpp_unsigned_integer<_Tp> || __libcpp_signed_integer<_Tp>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_ARITHMETIC_H
diff --git a/libcxx/include/__cxx03/__concepts/assignable.h b/libcxx/include/__cxx03/__concepts/assignable.h
new file mode 100644
index 00000000000000..7423daabba7801
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/assignable.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_ASSIGNABLE_H
+#define _LIBCPP___CONCEPTS_ASSIGNABLE_H
+
+#include <__concepts/common_reference_with.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/make_const_lvalue_ref.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.assignable]
+
+template <class _Lhs, class _Rhs>
+concept assignable_from =
+ is_lvalue_reference_v<_Lhs> &&
+ common_reference_with<__make_const_lvalue_ref<_Lhs>, __make_const_lvalue_ref<_Rhs>> &&
+ requires(_Lhs __lhs, _Rhs&& __rhs) {
+ { __lhs = std::forward<_Rhs>(__rhs) } -> same_as<_Lhs>;
+ };
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_ASSIGNABLE_H
diff --git a/libcxx/include/__cxx03/__concepts/boolean_testable.h b/libcxx/include/__cxx03/__concepts/boolean_testable.h
new file mode 100644
index 00000000000000..b379fe9c5a8804
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/boolean_testable.h
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_BOOLEAN_TESTABLE_H
+#define _LIBCPP___CONCEPTS_BOOLEAN_TESTABLE_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concepts.booleantestable]
+
+template <class _Tp>
+concept __boolean_testable_impl = convertible_to<_Tp, bool>;
+
+template <class _Tp>
+concept __boolean_testable = __boolean_testable_impl<_Tp> && requires(_Tp&& __t) {
+ { !std::forward<_Tp>(__t) } -> __boolean_testable_impl;
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_BOOLEAN_TESTABLE_H
diff --git a/libcxx/include/__cxx03/__concepts/class_or_enum.h b/libcxx/include/__cxx03/__concepts/class_or_enum.h
new file mode 100644
index 00000000000000..2739e31e14ba65
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/class_or_enum.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_CLASS_OR_ENUM_H
+#define _LIBCPP___CONCEPTS_CLASS_OR_ENUM_H
+
+#include <__config>
+#include <__type_traits/is_class.h>
+#include <__type_traits/is_enum.h>
+#include <__type_traits/is_union.h>
+#include <__type_traits/remove_cvref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// Whether a type is a class type or enumeration type according to the Core wording.
+
+template <class _Tp>
+concept __class_or_enum = is_class_v<_Tp> || is_union_v<_Tp> || is_enum_v<_Tp>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_CLASS_OR_ENUM_H
diff --git a/libcxx/include/__cxx03/__concepts/common_reference_with.h b/libcxx/include/__cxx03/__concepts/common_reference_with.h
new file mode 100644
index 00000000000000..4eb687e071bc51
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/common_reference_with.h
@@ -0,0 +1,36 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_COMMON_REFERENCE_WITH_H
+#define _LIBCPP___CONCEPTS_COMMON_REFERENCE_WITH_H
+
+#include <__concepts/convertible_to.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__type_traits/common_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.commonref]
+
+template <class _Tp, class _Up>
+concept common_reference_with =
+ same_as<common_reference_t<_Tp, _Up>, common_reference_t<_Up, _Tp>> &&
+ convertible_to<_Tp, common_reference_t<_Tp, _Up>> && convertible_to<_Up, common_reference_t<_Tp, _Up>>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_COMMON_REFERENCE_WITH_H
diff --git a/libcxx/include/__cxx03/__concepts/common_with.h b/libcxx/include/__cxx03/__concepts/common_with.h
new file mode 100644
index 00000000000000..85abb05efbc292
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/common_with.h
@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_COMMON_WITH_H
+#define _LIBCPP___CONCEPTS_COMMON_WITH_H
+
+#include <__concepts/common_reference_with.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/common_reference.h>
+#include <__type_traits/common_type.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.common]
+
+// clang-format off
+template <class _Tp, class _Up>
+concept common_with =
+ same_as<common_type_t<_Tp, _Up>, common_type_t<_Up, _Tp>> &&
+ requires {
+ static_cast<common_type_t<_Tp, _Up>>(std::declval<_Tp>());
+ static_cast<common_type_t<_Tp, _Up>>(std::declval<_Up>());
+ } &&
+ common_reference_with<
+ add_lvalue_reference_t<const _Tp>,
+ add_lvalue_reference_t<const _Up>> &&
+ common_reference_with<
+ add_lvalue_reference_t<common_type_t<_Tp, _Up>>,
+ common_reference_t<
+ add_lvalue_reference_t<const _Tp>,
+ add_lvalue_reference_t<const _Up>>>;
+// clang-format on
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_COMMON_WITH_H
diff --git a/libcxx/include/__cxx03/__concepts/constructible.h b/libcxx/include/__cxx03/__concepts/constructible.h
new file mode 100644
index 00000000000000..835a44429c092f
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/constructible.h
@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_CONSTRUCTIBLE_H
+#define _LIBCPP___CONCEPTS_CONSTRUCTIBLE_H
+
+#include <__concepts/convertible_to.h>
+#include <__concepts/destructible.h>
+#include <__config>
+#include <__type_traits/is_constructible.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.constructible]
+template <class _Tp, class... _Args>
+concept constructible_from = destructible<_Tp> && is_constructible_v<_Tp, _Args...>;
+
+// [concept.default.init]
+
+template <class _Tp>
+concept __default_initializable = requires { ::new _Tp; };
+
+template <class _Tp>
+concept default_initializable = constructible_from<_Tp> && requires { _Tp{}; } && __default_initializable<_Tp>;
+
+// [concept.moveconstructible]
+template <class _Tp>
+concept move_constructible = constructible_from<_Tp, _Tp> && convertible_to<_Tp, _Tp>;
+
+// [concept.copyconstructible]
+// clang-format off
+template <class _Tp>
+concept copy_constructible =
+ move_constructible<_Tp> &&
+ constructible_from<_Tp, _Tp&> && convertible_to<_Tp&, _Tp> &&
+ constructible_from<_Tp, const _Tp&> && convertible_to<const _Tp&, _Tp> &&
+ constructible_from<_Tp, const _Tp> && convertible_to<const _Tp, _Tp>;
+// clang-format on
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_CONSTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__concepts/convertible_to.h b/libcxx/include/__cxx03/__concepts/convertible_to.h
new file mode 100644
index 00000000000000..6d5b6c1268d5d2
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/convertible_to.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_CONVERTIBLE_TO_H
+#define _LIBCPP___CONCEPTS_CONVERTIBLE_TO_H
+
+#include <__config>
+#include <__type_traits/is_convertible.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.convertible]
+
+template <class _From, class _To>
+concept convertible_to = is_convertible_v<_From, _To> && requires { static_cast<_To>(std::declval<_From>()); };
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_CONVERTIBLE_TO_H
diff --git a/libcxx/include/__cxx03/__concepts/copyable.h b/libcxx/include/__cxx03/__concepts/copyable.h
new file mode 100644
index 00000000000000..2bf0ad42fc1a83
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/copyable.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_COPYABLE_H
+#define _LIBCPP___CONCEPTS_COPYABLE_H
+
+#include <__concepts/assignable.h>
+#include <__concepts/constructible.h>
+#include <__concepts/movable.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concepts.object]
+
+// clang-format off
+template <class _Tp>
+concept copyable =
+ copy_constructible<_Tp> &&
+ movable<_Tp> &&
+ assignable_from<_Tp&, _Tp&> &&
+ assignable_from<_Tp&, const _Tp&> &&
+ assignable_from<_Tp&, const _Tp>;
+// clang-format on
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_COPYABLE_H
diff --git a/libcxx/include/__cxx03/__concepts/derived_from.h b/libcxx/include/__cxx03/__concepts/derived_from.h
new file mode 100644
index 00000000000000..9875faee81b901
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/derived_from.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_DERIVED_FROM_H
+#define _LIBCPP___CONCEPTS_DERIVED_FROM_H
+
+#include <__config>
+#include <__type_traits/is_base_of.h>
+#include <__type_traits/is_convertible.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.derived]
+
+template <class _Dp, class _Bp>
+concept derived_from = is_base_of_v<_Bp, _Dp> && is_convertible_v<const volatile _Dp*, const volatile _Bp*>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_DERIVED_FROM_H
diff --git a/libcxx/include/__cxx03/__concepts/destructible.h b/libcxx/include/__cxx03/__concepts/destructible.h
new file mode 100644
index 00000000000000..28b4b1bc24ec9f
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/destructible.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_DESTRUCTIBLE_H
+#define _LIBCPP___CONCEPTS_DESTRUCTIBLE_H
+
+#include <__config>
+#include <__type_traits/is_nothrow_destructible.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.destructible]
+
+template <class _Tp>
+concept destructible = is_nothrow_destructible_v<_Tp>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_DESTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__concepts/different_from.h b/libcxx/include/__cxx03/__concepts/different_from.h
new file mode 100644
index 00000000000000..fd31f6e25805d3
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/different_from.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_DIFFERENT_FROM_H
+#define _LIBCPP___CONCEPTS_DIFFERENT_FROM_H
+
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__type_traits/remove_cvref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp, class _Up>
+concept __different_from = !same_as<remove_cvref_t<_Tp>, remove_cvref_t<_Up>>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_DIFFERENT_FROM_H
diff --git a/libcxx/include/__cxx03/__concepts/equality_comparable.h b/libcxx/include/__cxx03/__concepts/equality_comparable.h
new file mode 100644
index 00000000000000..278fc76409289b
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/equality_comparable.h
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H
+#define _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H
+
+#include <__concepts/boolean_testable.h>
+#include <__concepts/common_reference_with.h>
+#include <__config>
+#include <__type_traits/common_reference.h>
+#include <__type_traits/make_const_lvalue_ref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.equalitycomparable]
+
+template <class _Tp, class _Up>
+concept __weakly_equality_comparable_with =
+ requires(__make_const_lvalue_ref<_Tp> __t, __make_const_lvalue_ref<_Up> __u) {
+ { __t == __u } -> __boolean_testable;
+ { __t != __u } -> __boolean_testable;
+ { __u == __t } -> __boolean_testable;
+ { __u != __t } -> __boolean_testable;
+ };
+
+template <class _Tp>
+concept equality_comparable = __weakly_equality_comparable_with<_Tp, _Tp>;
+
+// clang-format off
+template <class _Tp, class _Up>
+concept equality_comparable_with =
+ equality_comparable<_Tp> && equality_comparable<_Up> &&
+ common_reference_with<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>> &&
+ equality_comparable<
+ common_reference_t<
+ __make_const_lvalue_ref<_Tp>,
+ __make_const_lvalue_ref<_Up>>> &&
+ __weakly_equality_comparable_with<_Tp, _Up>;
+// clang-format on
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H
diff --git a/libcxx/include/__cxx03/__concepts/invocable.h b/libcxx/include/__cxx03/__concepts/invocable.h
new file mode 100644
index 00000000000000..8a29398b3a29f8
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/invocable.h
@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_INVOCABLE_H
+#define _LIBCPP___CONCEPTS_INVOCABLE_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.invocable]
+
+template <class _Fn, class... _Args>
+concept invocable = requires(_Fn&& __fn, _Args&&... __args) {
+ std::invoke(std::forward<_Fn>(__fn), std::forward<_Args>(__args)...); // not required to be equality preserving
+};
+
+// [concept.regular.invocable]
+
+template <class _Fn, class... _Args>
+concept regular_invocable = invocable<_Fn, _Args...>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_INVOCABLE_H
diff --git a/libcxx/include/__cxx03/__concepts/movable.h b/libcxx/include/__cxx03/__concepts/movable.h
new file mode 100644
index 00000000000000..bc5b9d767c6a51
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/movable.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_MOVABLE_H
+#define _LIBCPP___CONCEPTS_MOVABLE_H
+
+#include <__concepts/assignable.h>
+#include <__concepts/constructible.h>
+#include <__concepts/swappable.h>
+#include <__config>
+#include <__type_traits/is_object.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concepts.object]
+
+template <class _Tp>
+concept movable = is_object_v<_Tp> && move_constructible<_Tp> && assignable_from<_Tp&, _Tp> && swappable<_Tp>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_MOVABLE_H
diff --git a/libcxx/include/__cxx03/__concepts/predicate.h b/libcxx/include/__cxx03/__concepts/predicate.h
new file mode 100644
index 00000000000000..00731efc8fcd9e
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/predicate.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_PREDICATE_H
+#define _LIBCPP___CONCEPTS_PREDICATE_H
+
+#include <__concepts/boolean_testable.h>
+#include <__concepts/invocable.h>
+#include <__config>
+#include <__functional/invoke.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.predicate]
+
+template <class _Fn, class... _Args>
+concept predicate = regular_invocable<_Fn, _Args...> && __boolean_testable<invoke_result_t<_Fn, _Args...>>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_PREDICATE_H
diff --git a/libcxx/include/__cxx03/__concepts/regular.h b/libcxx/include/__cxx03/__concepts/regular.h
new file mode 100644
index 00000000000000..9f3d8bf30be3e0
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/regular.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_REGULAR_H
+#define _LIBCPP___CONCEPTS_REGULAR_H
+
+#include <__concepts/equality_comparable.h>
+#include <__concepts/semiregular.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.object]
+
+template <class _Tp>
+concept regular = semiregular<_Tp> && equality_comparable<_Tp>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_REGULAR_H
diff --git a/libcxx/include/__cxx03/__concepts/relation.h b/libcxx/include/__cxx03/__concepts/relation.h
new file mode 100644
index 00000000000000..7545a7db93da76
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/relation.h
@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_RELATION_H
+#define _LIBCPP___CONCEPTS_RELATION_H
+
+#include <__concepts/predicate.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.relation]
+
+template <class _Rp, class _Tp, class _Up>
+concept relation =
+ predicate<_Rp, _Tp, _Tp> && predicate<_Rp, _Up, _Up> && predicate<_Rp, _Tp, _Up> && predicate<_Rp, _Up, _Tp>;
+
+// [concept.equiv]
+
+template <class _Rp, class _Tp, class _Up>
+concept equivalence_relation = relation<_Rp, _Tp, _Up>;
+
+// [concept.strictweakorder]
+
+template <class _Rp, class _Tp, class _Up>
+concept strict_weak_order = relation<_Rp, _Tp, _Up>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_RELATION_H
diff --git a/libcxx/include/__cxx03/__concepts/same_as.h b/libcxx/include/__cxx03/__concepts/same_as.h
new file mode 100644
index 00000000000000..4241131c70c1f4
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/same_as.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_SAME_AS_H
+#define _LIBCPP___CONCEPTS_SAME_AS_H
+
+#include <__config>
+#include <__type_traits/is_same.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.same]
+
+template <class _Tp, class _Up>
+concept __same_as_impl = _IsSame<_Tp, _Up>::value;
+
+template <class _Tp, class _Up>
+concept same_as = __same_as_impl<_Tp, _Up> && __same_as_impl<_Up, _Tp>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_SAME_AS_H
diff --git a/libcxx/include/__cxx03/__concepts/semiregular.h b/libcxx/include/__cxx03/__concepts/semiregular.h
new file mode 100644
index 00000000000000..7a159d17dfc109
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/semiregular.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_SEMIREGULAR_H
+#define _LIBCPP___CONCEPTS_SEMIREGULAR_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/copyable.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.object]
+
+template <class _Tp>
+concept semiregular = copyable<_Tp> && default_initializable<_Tp>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_SEMIREGULAR_H
diff --git a/libcxx/include/__cxx03/__concepts/swappable.h b/libcxx/include/__cxx03/__concepts/swappable.h
new file mode 100644
index 00000000000000..d339488a087a5c
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/swappable.h
@@ -0,0 +1,123 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_SWAPPABLE_H
+#define _LIBCPP___CONCEPTS_SWAPPABLE_H
+
+#include <__concepts/assignable.h>
+#include <__concepts/class_or_enum.h>
+#include <__concepts/common_reference_with.h>
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__type_traits/extent.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/exchange.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.swappable]
+
+namespace ranges {
+namespace __swap {
+
+template <class _Tp>
+void swap(_Tp&, _Tp&) = delete;
+
+// clang-format off
+template <class _Tp, class _Up>
+concept __unqualified_swappable_with =
+ (__class_or_enum<remove_cvref_t<_Tp>> || __class_or_enum<remove_cvref_t<_Up>>) &&
+ requires(_Tp&& __t, _Up&& __u) {
+ swap(std::forward<_Tp>(__t), std::forward<_Up>(__u));
+ };
+// clang-format on
+
+struct __fn;
+
+// clang-format off
+template <class _Tp, class _Up, size_t _Size>
+concept __swappable_arrays =
+ !__unqualified_swappable_with<_Tp (&)[_Size], _Up (&)[_Size]> &&
+ extent_v<_Tp> == extent_v<_Up> &&
+ requires(_Tp (&__t)[_Size], _Up (&__u)[_Size], const __fn& __swap) {
+ __swap(__t[0], __u[0]);
+ };
+// clang-format on
+
+template <class _Tp>
+concept __exchangeable =
+ !__unqualified_swappable_with<_Tp&, _Tp&> && move_constructible<_Tp> && assignable_from<_Tp&, _Tp>;
+
+struct __fn {
+ // 2.1 `S` is `(void)swap(E1, E2)`* if `E1` or `E2` has class or enumeration type and...
+ // *The name `swap` is used here unqualified.
+ template <class _Tp, class _Up>
+ requires __unqualified_swappable_with<_Tp, _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(swap(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) {
+ swap(std::forward<_Tp>(__t), std::forward<_Up>(__u));
+ }
+
+ // 2.2 Otherwise, if `E1` and `E2` are lvalues of array types with equal extent and...
+ template <class _Tp, class _Up, size_t _Size>
+ requires __swappable_arrays<_Tp, _Up, _Size>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_Tp (&__t)[_Size], _Up (&__u)[_Size]) const
+ noexcept(noexcept((*this)(*__t, *__u))) {
+ // TODO(cjdb): replace with `ranges::swap_ranges`.
+ for (size_t __i = 0; __i < _Size; ++__i) {
+ (*this)(__t[__i], __u[__i]);
+ }
+ }
+
+ // 2.3 Otherwise, if `E1` and `E2` are lvalues of the same type `T` that models...
+ template <__exchangeable _Tp>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_Tp& __x, _Tp& __y) const
+ noexcept(is_nothrow_move_constructible_v<_Tp> && is_nothrow_move_assignable_v<_Tp>) {
+ __y = std::exchange(__x, std::move(__y));
+ }
+};
+} // namespace __swap
+
+inline namespace __cpo {
+inline constexpr auto swap = __swap::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+template <class _Tp>
+concept swappable = requires(_Tp& __a, _Tp& __b) { ranges::swap(__a, __b); };
+
+template <class _Tp, class _Up>
+concept swappable_with = common_reference_with<_Tp, _Up> && requires(_Tp&& __t, _Up&& __u) {
+ ranges::swap(std::forward<_Tp>(__t), std::forward<_Tp>(__t));
+ ranges::swap(std::forward<_Up>(__u), std::forward<_Up>(__u));
+ ranges::swap(std::forward<_Tp>(__t), std::forward<_Up>(__u));
+ ranges::swap(std::forward<_Up>(__u), std::forward<_Tp>(__t));
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CONCEPTS_SWAPPABLE_H
diff --git a/libcxx/include/__cxx03/__concepts/totally_ordered.h b/libcxx/include/__cxx03/__concepts/totally_ordered.h
new file mode 100644
index 00000000000000..186c3b430dd54d
--- /dev/null
+++ b/libcxx/include/__cxx03/__concepts/totally_ordered.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONCEPTS_TOTALLY_ORDERED_H
+#define _LIBCPP___CONCEPTS_TOTALLY_ORDERED_H
+
+#include <__concepts/boolean_testable.h>
+#include <__concepts/equality_comparable.h>
+#include <__config>
+#include <__type_traits/common_reference.h>
+#include <__type_traits/make_const_lvalue_ref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [concept.totallyordered]
+
+template <class _Tp, class _Up>
+concept __partially_ordered_with = requires(__make_const_lvalue_ref<_Tp> __t, __make_const_lvalue_ref<_Up> __u) {
+ { __t < __u } -> __boolean_testable;
+ { __t > __u } -> __boolean_testable;
+ { __t <= __u } -> __boolean_testable;
+ { __t >= __u } -> __boolean_testable;
+ { __u < __t } -> __boolean_testable;
+ { __u > __t } -> __boolean_testable;
+ { __u <= __t } -> __boolean_testable;
+ { __u >= __t } -> __boolean_testable;
+};
+
+template <class _Tp>
+concept totally_ordered = equality_comparable<_Tp> && __partially_ordered_with<_Tp, _Tp>;
+
+// clang-format off
+template <class _Tp, class _Up>
+concept totally_ordered_with =
+ totally_ordered<_Tp> && totally_ordered<_Up> &&
+ equality_comparable_with<_Tp, _Up> &&
+ totally_ordered<
+ common_reference_t<
+ __make_const_lvalue_ref<_Tp>,
+ __make_const_lvalue_ref<_Up>>> &&
+ __partially_ordered_with<_Tp, _Up>;
+// clang-format on
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CONCEPTS_TOTALLY_ORDERED_H
diff --git a/libcxx/include/__cxx03/__condition_variable/condition_variable.h b/libcxx/include/__cxx03/__condition_variable/condition_variable.h
new file mode 100644
index 00000000000000..de35aaca1070eb
--- /dev/null
+++ b/libcxx/include/__cxx03/__condition_variable/condition_variable.h
@@ -0,0 +1,244 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONDITION_VARIABLE_CONDITION_VARIABLE_H
+#define _LIBCPP___CONDITION_VARIABLE_CONDITION_VARIABLE_H
+
+#include <__chrono/duration.h>
+#include <__chrono/steady_clock.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/time_point.h>
+#include <__config>
+#include <__mutex/mutex.h>
+#include <__mutex/unique_lock.h>
+#include <__system_error/system_error.h>
+#include <__thread/support.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_floating_point.h>
+#include <__utility/move.h>
+#include <limits>
+#include <ratio>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+
+// enum class cv_status
+_LIBCPP_DECLARE_STRONG_ENUM(cv_status){no_timeout, timeout};
+_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(cv_status)
+
+class _LIBCPP_EXPORTED_FROM_ABI condition_variable {
+ __libcpp_condvar_t __cv_ = _LIBCPP_CONDVAR_INITIALIZER;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR condition_variable() _NOEXCEPT = default;
+
+# ifdef _LIBCPP_HAS_TRIVIAL_CONDVAR_DESTRUCTION
+ ~condition_variable() = default;
+# else
+ ~condition_variable();
+# endif
+
+ condition_variable(const condition_variable&) = delete;
+ condition_variable& operator=(const condition_variable&) = delete;
+
+ void notify_one() _NOEXCEPT;
+ void notify_all() _NOEXCEPT;
+
+ void wait(unique_lock<mutex>& __lk) _NOEXCEPT;
+ template <class _Predicate>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS void wait(unique_lock<mutex>& __lk, _Predicate __pred);
+
+ template <class _Clock, class _Duration>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS cv_status
+ wait_until(unique_lock<mutex>& __lk, const chrono::time_point<_Clock, _Duration>& __t);
+
+ template <class _Clock, class _Duration, class _Predicate>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS bool
+ wait_until(unique_lock<mutex>& __lk, const chrono::time_point<_Clock, _Duration>& __t, _Predicate __pred);
+
+ template <class _Rep, class _Period>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS cv_status
+ wait_for(unique_lock<mutex>& __lk, const chrono::duration<_Rep, _Period>& __d);
+
+ template <class _Rep, class _Period, class _Predicate>
+ bool _LIBCPP_HIDE_FROM_ABI
+ wait_for(unique_lock<mutex>& __lk, const chrono::duration<_Rep, _Period>& __d, _Predicate __pred);
+
+ typedef __libcpp_condvar_t* native_handle_type;
+ _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() { return &__cv_; }
+
+private:
+ void
+ __do_timed_wait(unique_lock<mutex>& __lk, chrono::time_point<chrono::system_clock, chrono::nanoseconds>) _NOEXCEPT;
+# if defined(_LIBCPP_HAS_COND_CLOCKWAIT)
+ _LIBCPP_HIDE_FROM_ABI void
+ __do_timed_wait(unique_lock<mutex>& __lk, chrono::time_point<chrono::steady_clock, chrono::nanoseconds>) _NOEXCEPT;
+# endif
+ template <class _Clock>
+ _LIBCPP_HIDE_FROM_ABI void
+ __do_timed_wait(unique_lock<mutex>& __lk, chrono::time_point<_Clock, chrono::nanoseconds>) _NOEXCEPT;
+};
+#endif // !_LIBCPP_HAS_NO_THREADS
+
+template <class _Rep, class _Period, __enable_if_t<is_floating_point<_Rep>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI chrono::nanoseconds __safe_nanosecond_cast(chrono::duration<_Rep, _Period> __d) {
+ using namespace chrono;
+ using __ratio = ratio_divide<_Period, nano>;
+ using __ns_rep = nanoseconds::rep;
+ _Rep __result_float = __d.count() * __ratio::num / __ratio::den;
+
+ _Rep __result_max = numeric_limits<__ns_rep>::max();
+ if (__result_float >= __result_max) {
+ return nanoseconds::max();
+ }
+
+ _Rep __result_min = numeric_limits<__ns_rep>::min();
+ if (__result_float <= __result_min) {
+ return nanoseconds::min();
+ }
+
+ return nanoseconds(static_cast<__ns_rep>(__result_float));
+}
+
+template <class _Rep, class _Period, __enable_if_t<!is_floating_point<_Rep>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI chrono::nanoseconds __safe_nanosecond_cast(chrono::duration<_Rep, _Period> __d) {
+ using namespace chrono;
+ if (__d.count() == 0) {
+ return nanoseconds(0);
+ }
+
+ using __ratio = ratio_divide<_Period, nano>;
+ using __ns_rep = nanoseconds::rep;
+ __ns_rep __result_max = numeric_limits<__ns_rep>::max();
+ if (__d.count() > 0 && __d.count() > __result_max / __ratio::num) {
+ return nanoseconds::max();
+ }
+
+ __ns_rep __result_min = numeric_limits<__ns_rep>::min();
+ if (__d.count() < 0 && __d.count() < __result_min / __ratio::num) {
+ return nanoseconds::min();
+ }
+
+ __ns_rep __result = __d.count() * __ratio::num / __ratio::den;
+ if (__result == 0) {
+ return nanoseconds(1);
+ }
+
+ return nanoseconds(__result);
+}
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+template <class _Predicate>
+void condition_variable::wait(unique_lock<mutex>& __lk, _Predicate __pred) {
+ while (!__pred())
+ wait(__lk);
+}
+
+template <class _Clock, class _Duration>
+cv_status condition_variable::wait_until(unique_lock<mutex>& __lk, const chrono::time_point<_Clock, _Duration>& __t) {
+ using namespace chrono;
+ using __clock_tp_ns = time_point<_Clock, nanoseconds>;
+
+ typename _Clock::time_point __now = _Clock::now();
+ if (__t <= __now)
+ return cv_status::timeout;
+
+ __clock_tp_ns __t_ns = __clock_tp_ns(std::__safe_nanosecond_cast(__t.time_since_epoch()));
+
+ __do_timed_wait(__lk, __t_ns);
+ return _Clock::now() < __t ? cv_status::no_timeout : cv_status::timeout;
+}
+
+template <class _Clock, class _Duration, class _Predicate>
+bool condition_variable::wait_until(
+ unique_lock<mutex>& __lk, const chrono::time_point<_Clock, _Duration>& __t, _Predicate __pred) {
+ while (!__pred()) {
+ if (wait_until(__lk, __t) == cv_status::timeout)
+ return __pred();
+ }
+ return true;
+}
+
+template <class _Rep, class _Period>
+cv_status condition_variable::wait_for(unique_lock<mutex>& __lk, const chrono::duration<_Rep, _Period>& __d) {
+ using namespace chrono;
+ if (__d <= __d.zero())
+ return cv_status::timeout;
+ using __ns_rep = nanoseconds::rep;
+ steady_clock::time_point __c_now = steady_clock::now();
+
+# if defined(_LIBCPP_HAS_COND_CLOCKWAIT)
+ using __clock_tp_ns = time_point<steady_clock, nanoseconds>;
+ __ns_rep __now_count_ns = std::__safe_nanosecond_cast(__c_now.time_since_epoch()).count();
+# else
+ using __clock_tp_ns = time_point<system_clock, nanoseconds>;
+ __ns_rep __now_count_ns = std::__safe_nanosecond_cast(system_clock::now().time_since_epoch()).count();
+# endif
+
+ __ns_rep __d_ns_count = std::__safe_nanosecond_cast(__d).count();
+
+ if (__now_count_ns > numeric_limits<__ns_rep>::max() - __d_ns_count) {
+ __do_timed_wait(__lk, __clock_tp_ns::max());
+ } else {
+ __do_timed_wait(__lk, __clock_tp_ns(nanoseconds(__now_count_ns + __d_ns_count)));
+ }
+
+ return steady_clock::now() - __c_now < __d ? cv_status::no_timeout : cv_status::timeout;
+}
+
+template <class _Rep, class _Period, class _Predicate>
+inline bool
+condition_variable::wait_for(unique_lock<mutex>& __lk, const chrono::duration<_Rep, _Period>& __d, _Predicate __pred) {
+ return wait_until(__lk, chrono::steady_clock::now() + __d, std::move(__pred));
+}
+
+# if defined(_LIBCPP_HAS_COND_CLOCKWAIT)
+inline void condition_variable::__do_timed_wait(
+ unique_lock<mutex>& __lk, chrono::time_point<chrono::steady_clock, chrono::nanoseconds> __tp) _NOEXCEPT {
+ using namespace chrono;
+ if (!__lk.owns_lock())
+ __throw_system_error(EPERM, "condition_variable::timed wait: mutex not locked");
+ nanoseconds __d = __tp.time_since_epoch();
+ timespec __ts;
+ seconds __s = duration_cast<seconds>(__d);
+ using __ts_sec = decltype(__ts.tv_sec);
+ const __ts_sec __ts_sec_max = numeric_limits<__ts_sec>::max();
+ if (__s.count() < __ts_sec_max) {
+ __ts.tv_sec = static_cast<__ts_sec>(__s.count());
+ __ts.tv_nsec = (__d - __s).count();
+ } else {
+ __ts.tv_sec = __ts_sec_max;
+ __ts.tv_nsec = giga::num - 1;
+ }
+ int __ec = pthread_cond_clockwait(&__cv_, __lk.mutex()->native_handle(), CLOCK_MONOTONIC, &__ts);
+ if (__ec != 0 && __ec != ETIMEDOUT)
+ __throw_system_error(__ec, "condition_variable timed_wait failed");
+}
+# endif // _LIBCPP_HAS_COND_CLOCKWAIT
+
+template <class _Clock>
+inline void condition_variable::__do_timed_wait(unique_lock<mutex>& __lk,
+ chrono::time_point<_Clock, chrono::nanoseconds> __tp) _NOEXCEPT {
+ wait_for(__lk, __tp - _Clock::now());
+}
+
+#endif // _LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CONDITION_VARIABLE_CONDITION_VARIABLE_H
diff --git a/libcxx/include/__cxx03/__config b/libcxx/include/__cxx03/__config
new file mode 100644
index 00000000000000..661af5be3c225e
--- /dev/null
+++ b/libcxx/include/__cxx03/__config
@@ -0,0 +1,1228 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONFIG
+#define _LIBCPP___CONFIG
+
+#include <__config_site>
+#include <__configuration/abi.h>
+#include <__configuration/availability.h>
+#include <__configuration/compiler.h>
+#include <__configuration/platform.h>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+#ifdef __cplusplus
+
+// The attributes supported by clang are documented at https://clang.llvm.org/docs/AttributeReference.html
+
+// _LIBCPP_VERSION represents the version of libc++, which matches the version of LLVM.
+// Given a LLVM release LLVM XX.YY.ZZ (e.g. LLVM 17.0.1 == 17.00.01), _LIBCPP_VERSION is
+// defined to XXYYZZ.
+# define _LIBCPP_VERSION 190100
+
+# define _LIBCPP_CONCAT_IMPL(_X, _Y) _X##_Y
+# define _LIBCPP_CONCAT(_X, _Y) _LIBCPP_CONCAT_IMPL(_X, _Y)
+
+# if __STDC_HOSTED__ == 0
+# define _LIBCPP_FREESTANDING
+# endif
+
+// HARDENING {
+
+// This is for backward compatibility -- make enabling `_LIBCPP_ENABLE_ASSERTIONS` (which predates hardening modes)
+// equivalent to setting the extensive mode. This is deprecated and will be removed in LLVM 20.
+# ifdef _LIBCPP_ENABLE_ASSERTIONS
+# warning "_LIBCPP_ENABLE_ASSERTIONS is deprecated, please use _LIBCPP_HARDENING_MODE instead"
+# if _LIBCPP_ENABLE_ASSERTIONS != 0 && _LIBCPP_ENABLE_ASSERTIONS != 1
+# error "_LIBCPP_ENABLE_ASSERTIONS must be set to 0 or 1"
+# endif
+# if _LIBCPP_ENABLE_ASSERTIONS
+# define _LIBCPP_HARDENING_MODE _LIBCPP_HARDENING_MODE_EXTENSIVE
+# endif
+# endif
+
+// The library provides the macro `_LIBCPP_HARDENING_MODE` which can be set to one of the following values:
+//
+// - `_LIBCPP_HARDENING_MODE_NONE`;
+// - `_LIBCPP_HARDENING_MODE_FAST`;
+// - `_LIBCPP_HARDENING_MODE_EXTENSIVE`;
+// - `_LIBCPP_HARDENING_MODE_DEBUG`.
+//
+// These values have the following effects:
+//
+// - `_LIBCPP_HARDENING_MODE_NONE` -- sets the hardening mode to "none" which disables all runtime hardening checks;
+//
+// - `_LIBCPP_HARDENING_MODE_FAST` -- sets that hardening mode to "fast". The fast mode enables security-critical checks
+// that can be done with relatively little runtime overhead in constant time;
+//
+// - `_LIBCPP_HARDENING_MODE_EXTENSIVE` -- sets the hardening mode to "extensive". The extensive mode is a superset of
+// the fast mode that additionally enables checks that are relatively cheap and prevent common types of logic errors
+// but are not necessarily security-critical;
+//
+// - `_LIBCPP_HARDENING_MODE_DEBUG` -- sets the hardening mode to "debug". The debug mode is a superset of the extensive
+// mode and enables all checks available in the library, including internal assertions. Checks that are part of the
+// debug mode can be very expensive and thus the debug mode is intended to be used for testing, not in production.
+
+// Inside the library, assertions are categorized so they can be cherry-picked based on the chosen hardening mode. These
+// macros are only for internal use -- users should only pick one of the high-level hardening modes described above.
+//
+// - `_LIBCPP_ASSERT_VALID_INPUT_RANGE` -- checks that ranges (whether expressed as an iterator pair, an iterator and
+// a sentinel, an iterator and a count, or a `std::range`) given as input to library functions are valid:
+// - the sentinel is reachable from the begin iterator;
+// - TODO(hardening): both iterators refer to the same container.
+//
+// - `_LIBCPP_ASSERT_VALID_ELEMENT_ACCESS` -- checks that any attempts to access a container element, whether through
+// the container object or through an iterator, are valid and do not attempt to go out of bounds or otherwise access
+// a non-existent element. For iterator checks to work, bounded iterators must be enabled in the ABI. Types like
+// `optional` and `function` are considered one-element containers for the purposes of this check.
+//
+// - `_LIBCPP_ASSERT_NON_NULL` -- checks that the pointer being dereferenced is not null. On most modern platforms zero
+// address does not refer to an actual location in memory, so a null pointer dereference would not compromize the
+// memory security of a program (however, it is still undefined behavior that can result in strange errors due to
+// compiler optimizations).
+//
+// - `_LIBCPP_ASSERT_NON_OVERLAPPING_RANGES` -- for functions that take several ranges as arguments, checks that the
+// given ranges do not overlap.
+//
+// - `_LIBCPP_ASSERT_VALID_DEALLOCATION` -- checks that an attempt to deallocate memory is valid (e.g. the given object
+// was allocated by the given allocator). Violating this category typically results in a memory leak.
+//
+// - `_LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL` -- checks that a call to an external API doesn't fail in
+// an unexpected manner. This includes triggering documented cases of undefined behavior in an external library (like
+// attempting to unlock an unlocked mutex in pthreads). Any API external to the library falls under this category
+// (from system calls to compiler intrinsics). We generally don't expect these failures to compromize memory safety or
+// otherwise create an immediate security issue.
+//
+// - `_LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR` -- checks any operations that exchange nodes between containers to make sure
+// the containers have compatible allocators.
+//
+// - `_LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN` -- checks that the given argument is within the domain of valid arguments
+// for the function. Violating this typically produces an incorrect result (e.g. the clamp algorithm returns the
+// original value without clamping it due to incorrect functors) or puts an object into an invalid state (e.g.
+// a string view where only a subset of elements is possible to access). This category is for assertions violating
+// which doesn't cause any immediate issues in the library -- whatever the consequences are, they will happen in the
+// user code.
+//
+// - `_LIBCPP_ASSERT_PEDANTIC` -- checks prerequisites which are imposed by the Standard, but violating which happens to
+// be benign in our implementation.
+//
+// - `_LIBCPP_ASSERT_SEMANTIC_REQUIREMENT` -- checks that the given argument satisfies the semantic requirements imposed
+// by the Standard. Typically, there is no simple way to completely prove that a semantic requirement is satisfied;
+// thus, this would often be a heuristic check and it might be quite expensive.
+//
+// - `_LIBCPP_ASSERT_INTERNAL` -- checks that internal invariants of the library hold. These assertions don't depend on
+// user input.
+//
+// - `_LIBCPP_ASSERT_UNCATEGORIZED` -- for assertions that haven't been properly classified yet.
+
+// clang-format off
+# define _LIBCPP_HARDENING_MODE_NONE (1 << 1)
+# define _LIBCPP_HARDENING_MODE_FAST (1 << 2)
+# define _LIBCPP_HARDENING_MODE_EXTENSIVE (1 << 4) // Deliberately not ordered.
+# define _LIBCPP_HARDENING_MODE_DEBUG (1 << 3)
+// clang-format on
+
+# ifndef _LIBCPP_HARDENING_MODE
+
+# ifndef _LIBCPP_HARDENING_MODE_DEFAULT
+# error _LIBCPP_HARDENING_MODE_DEFAULT is not defined. This definition should be set at configuration time in the \
+`__config_site` header, please make sure your installation of libc++ is not broken.
+# endif
+
+# define _LIBCPP_HARDENING_MODE _LIBCPP_HARDENING_MODE_DEFAULT
+# endif
+
+# if _LIBCPP_HARDENING_MODE != _LIBCPP_HARDENING_MODE_NONE && \
+ _LIBCPP_HARDENING_MODE != _LIBCPP_HARDENING_MODE_FAST && \
+ _LIBCPP_HARDENING_MODE != _LIBCPP_HARDENING_MODE_EXTENSIVE && \
+ _LIBCPP_HARDENING_MODE != _LIBCPP_HARDENING_MODE_DEBUG
+# error _LIBCPP_HARDENING_MODE must be set to one of the following values: \
+_LIBCPP_HARDENING_MODE_NONE, \
+_LIBCPP_HARDENING_MODE_FAST, \
+_LIBCPP_HARDENING_MODE_EXTENSIVE, \
+_LIBCPP_HARDENING_MODE_DEBUG
+# endif
+
+// } HARDENING
+
+# define _LIBCPP_TOSTRING2(x) #x
+# define _LIBCPP_TOSTRING(x) _LIBCPP_TOSTRING2(x)
+
+// NOLINTNEXTLINE(libcpp-cpp-version-check)
+# if __cplusplus < 201103L
+# define _LIBCPP_CXX03_LANG
+# endif
+
+# ifndef __has_constexpr_builtin
+# define __has_constexpr_builtin(x) 0
+# endif
+
+// This checks wheter a Clang module is built
+# ifndef __building_module
+# define __building_module(...) 0
+# endif
+
+// '__is_identifier' returns '0' if '__x' is a reserved identifier provided by
+// the compiler and '1' otherwise.
+# ifndef __is_identifier
+# define __is_identifier(__x) 1
+# endif
+
+# ifndef __has_declspec_attribute
+# define __has_declspec_attribute(__x) 0
+# endif
+
+# define __has_keyword(__x) !(__is_identifier(__x))
+
+# ifndef __has_warning
+# define __has_warning(...) 0
+# endif
+
+# if !defined(_LIBCPP_COMPILER_CLANG_BASED) && __cplusplus < 201103L
+# error "libc++ only supports C++03 with Clang-based compilers. Please enable C++11"
+# endif
+
+// FIXME: ABI detection should be done via compiler builtin macros. This
+// is just a placeholder until Clang implements such macros. For now assume
+// that Windows compilers pretending to be MSVC++ target the Microsoft ABI,
+// and allow the user to explicitly specify the ABI to handle cases where this
+// heuristic falls short.
+# if defined(_LIBCPP_ABI_FORCE_ITANIUM) && defined(_LIBCPP_ABI_FORCE_MICROSOFT)
+# error "Only one of _LIBCPP_ABI_FORCE_ITANIUM and _LIBCPP_ABI_FORCE_MICROSOFT can be defined"
+# elif defined(_LIBCPP_ABI_FORCE_ITANIUM)
+# define _LIBCPP_ABI_ITANIUM
+# elif defined(_LIBCPP_ABI_FORCE_MICROSOFT)
+# define _LIBCPP_ABI_MICROSOFT
+# else
+# if defined(_WIN32) && defined(_MSC_VER)
+# define _LIBCPP_ABI_MICROSOFT
+# else
+# define _LIBCPP_ABI_ITANIUM
+# endif
+# endif
+
+# if defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_NO_VCRUNTIME)
+# define _LIBCPP_ABI_VCRUNTIME
+# endif
+
+# if __has_feature(experimental_library)
+# ifndef _LIBCPP_ENABLE_EXPERIMENTAL
+# define _LIBCPP_ENABLE_EXPERIMENTAL
+# endif
+# endif
+
+// Incomplete features get their own specific disabling flags. This makes it
+// easier to grep for target specific flags once the feature is complete.
+# if !defined(_LIBCPP_ENABLE_EXPERIMENTAL) && !defined(_LIBCPP_BUILDING_LIBRARY)
+# define _LIBCPP_HAS_NO_INCOMPLETE_PSTL
+# define _LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN
+# define _LIBCPP_HAS_NO_EXPERIMENTAL_TZDB
+# define _LIBCPP_HAS_NO_EXPERIMENTAL_SYNCSTREAM
+# endif
+
+# if defined(__MVS__)
+# include <features.h> // for __NATIVE_ASCII_F
+# endif
+
+# if defined(_WIN32)
+# define _LIBCPP_WIN32API
+# define _LIBCPP_SHORT_WCHAR 1
+// Both MinGW and native MSVC provide a "MSVC"-like environment
+# define _LIBCPP_MSVCRT_LIKE
+// If mingw not explicitly detected, assume using MS C runtime only if
+// a MS compatibility version is specified.
+# if defined(_MSC_VER) && !defined(__MINGW32__)
+# define _LIBCPP_MSVCRT // Using Microsoft's C Runtime library
+# endif
+# if (defined(_M_AMD64) || defined(__x86_64__)) || (defined(_M_ARM) || defined(__arm__))
+# define _LIBCPP_HAS_BITSCAN64
+# endif
+# define _LIBCPP_HAS_OPEN_WITH_WCHAR
+# endif // defined(_WIN32)
+
+# if defined(_AIX) && !defined(__64BIT__)
+// The size of wchar is 2 byte on 32-bit mode on AIX.
+# define _LIBCPP_SHORT_WCHAR 1
+# endif
+
+// Libc++ supports various implementations of std::random_device.
+//
+// _LIBCPP_USING_DEV_RANDOM
+// Read entropy from the given file, by default `/dev/urandom`.
+// If a token is provided, it is assumed to be the path to a file
+// to read entropy from. This is the default behavior if nothing
+// else is specified. This implementation requires storing state
+// inside `std::random_device`.
+//
+// _LIBCPP_USING_ARC4_RANDOM
+// Use arc4random(). This allows obtaining random data even when
+// using sandboxing mechanisms. On some platforms like Apple, this
+// is the recommended source of entropy for user-space programs.
+// When this option is used, the token passed to `std::random_device`'s
+// constructor *must* be "/dev/urandom" -- anything else is an error.
+//
+// _LIBCPP_USING_GETENTROPY
+// Use getentropy().
+// When this option is used, the token passed to `std::random_device`'s
+// constructor *must* be "/dev/urandom" -- anything else is an error.
+//
+// _LIBCPP_USING_FUCHSIA_CPRNG
+// Use Fuchsia's zx_cprng_draw() system call, which is specified to
+// deliver high-quality entropy and cannot fail.
+// When this option is used, the token passed to `std::random_device`'s
+// constructor *must* be "/dev/urandom" -- anything else is an error.
+//
+// _LIBCPP_USING_NACL_RANDOM
+// NaCl's sandbox (which PNaCl also runs in) doesn't allow filesystem access,
+// including accesses to the special files under `/dev`. This implementation
+// uses the NaCL syscall `nacl_secure_random_init()` to get entropy.
+// When this option is used, the token passed to `std::random_device`'s
+// constructor *must* be "/dev/urandom" -- anything else is an error.
+//
+// _LIBCPP_USING_WIN32_RANDOM
+// Use rand_s(), for use on Windows.
+// When this option is used, the token passed to `std::random_device`'s
+// constructor *must* be "/dev/urandom" -- anything else is an error.
+# if defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
+ defined(__DragonFly__)
+# define _LIBCPP_USING_ARC4_RANDOM
+# elif defined(__wasi__) || defined(__EMSCRIPTEN__)
+# define _LIBCPP_USING_GETENTROPY
+# elif defined(__Fuchsia__)
+# define _LIBCPP_USING_FUCHSIA_CPRNG
+# elif defined(__native_client__)
+# define _LIBCPP_USING_NACL_RANDOM
+# elif defined(_LIBCPP_WIN32API)
+# define _LIBCPP_USING_WIN32_RANDOM
+# else
+# define _LIBCPP_USING_DEV_RANDOM
+# endif
+
+# ifndef _LIBCPP_CXX03_LANG
+
+# define _LIBCPP_ALIGNOF(_Tp) alignof(_Tp)
+# define _ALIGNAS_TYPE(x) alignas(x)
+# define _ALIGNAS(x) alignas(x)
+# define _LIBCPP_NORETURN [[noreturn]]
+# define _NOEXCEPT noexcept
+# define _NOEXCEPT_(...) noexcept(__VA_ARGS__)
+# define _LIBCPP_CONSTEXPR constexpr
+
+# else
+
+# define _LIBCPP_ALIGNOF(_Tp) _Alignof(_Tp)
+# define _ALIGNAS_TYPE(x) __attribute__((__aligned__(_LIBCPP_ALIGNOF(x))))
+# define _ALIGNAS(x) __attribute__((__aligned__(x)))
+# define _LIBCPP_NORETURN __attribute__((__noreturn__))
+# define _LIBCPP_HAS_NO_NOEXCEPT
+# define nullptr __nullptr
+# define _NOEXCEPT throw()
+# define _NOEXCEPT_(...)
+# define static_assert(...) _Static_assert(__VA_ARGS__)
+# define decltype(...) __decltype(__VA_ARGS__)
+# define _LIBCPP_CONSTEXPR
+
+typedef __char16_t char16_t;
+typedef __char32_t char32_t;
+
+# endif
+
+# define _LIBCPP_PREFERRED_ALIGNOF(_Tp) __alignof(_Tp)
+
+// Objective-C++ features (opt-in)
+# if __has_feature(objc_arc)
+# define _LIBCPP_HAS_OBJC_ARC
+# endif
+
+# if __has_feature(objc_arc_weak)
+# define _LIBCPP_HAS_OBJC_ARC_WEAK
+# endif
+
+# if __has_extension(blocks)
+# define _LIBCPP_HAS_EXTENSION_BLOCKS
+# endif
+
+# if defined(_LIBCPP_HAS_EXTENSION_BLOCKS) && defined(__APPLE__)
+# define _LIBCPP_HAS_BLOCKS_RUNTIME
+# endif
+
+# if !__has_feature(address_sanitizer)
+# define _LIBCPP_HAS_NO_ASAN
+# endif
+
+# define _LIBCPP_ALWAYS_INLINE __attribute__((__always_inline__))
+
+# define _LIBCPP_DISABLE_EXTENSION_WARNING __extension__
+
+# if defined(_LIBCPP_OBJECT_FORMAT_COFF)
+
+# ifdef _DLL
+# define _LIBCPP_CRT_FUNC __declspec(dllimport)
+# else
+# define _LIBCPP_CRT_FUNC
+# endif
+
+# if defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) || (defined(__MINGW32__) && !defined(_LIBCPP_BUILDING_LIBRARY))
+# define _LIBCPP_DLL_VIS
+# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
+# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+# define _LIBCPP_OVERRIDABLE_FUNC_VIS
+# define _LIBCPP_EXPORTED_FROM_ABI
+# elif defined(_LIBCPP_BUILDING_LIBRARY)
+# define _LIBCPP_DLL_VIS __declspec(dllexport)
+# if defined(__MINGW32__)
+# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS _LIBCPP_DLL_VIS
+# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+# else
+# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
+# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS _LIBCPP_DLL_VIS
+# endif
+# define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_DLL_VIS
+# define _LIBCPP_EXPORTED_FROM_ABI __declspec(dllexport)
+# else
+# define _LIBCPP_DLL_VIS __declspec(dllimport)
+# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS _LIBCPP_DLL_VIS
+# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+# define _LIBCPP_OVERRIDABLE_FUNC_VIS
+# define _LIBCPP_EXPORTED_FROM_ABI __declspec(dllimport)
+# endif
+
+# define _LIBCPP_HIDDEN
+# define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
+# define _LIBCPP_TEMPLATE_VIS
+# define _LIBCPP_TEMPLATE_DATA_VIS
+# define _LIBCPP_TYPE_VISIBILITY_DEFAULT
+
+# else
+
+# if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+# define _LIBCPP_VISIBILITY(vis) __attribute__((__visibility__(vis)))
+# else
+# define _LIBCPP_VISIBILITY(vis)
+# endif
+
+# define _LIBCPP_HIDDEN _LIBCPP_VISIBILITY("hidden")
+# define _LIBCPP_TEMPLATE_DATA_VIS _LIBCPP_VISIBILITY("default")
+# define _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_VISIBILITY("default")
+# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS _LIBCPP_VISIBILITY("default")
+# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+
+// TODO: Make this a proper customization point or remove the option to override it.
+# ifndef _LIBCPP_OVERRIDABLE_FUNC_VIS
+# define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_VISIBILITY("default")
+# endif
+
+# if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+// The inline should be removed once PR32114 is resolved
+# define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS inline _LIBCPP_HIDDEN
+# else
+# define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
+# endif
+
+// GCC doesn't support the type_visibility attribute, so we have to keep the visibility attribute on templates
+# if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) && !__has_attribute(__type_visibility__)
+# define _LIBCPP_TEMPLATE_VIS __attribute__((__visibility__("default")))
+# else
+# define _LIBCPP_TEMPLATE_VIS
+# endif
+
+# if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) && __has_attribute(__type_visibility__)
+# define _LIBCPP_TYPE_VISIBILITY_DEFAULT __attribute__((__type_visibility__("default")))
+# else
+# define _LIBCPP_TYPE_VISIBILITY_DEFAULT
+# endif
+
+# endif // defined(_LIBCPP_OBJECT_FORMAT_COFF)
+
+# if __has_attribute(exclude_from_explicit_instantiation)
+# define _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION __attribute__((__exclude_from_explicit_instantiation__))
+# else
+// Try to approximate the effect of exclude_from_explicit_instantiation
+// (which is that entities are not assumed to be provided by explicit
+// template instantiations in the dylib) by always inlining those entities.
+# define _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION _LIBCPP_ALWAYS_INLINE
+# endif
+
+# ifdef _LIBCPP_COMPILER_CLANG_BASED
+# define _LIBCPP_DIAGNOSTIC_PUSH _Pragma("clang diagnostic push")
+# define _LIBCPP_DIAGNOSTIC_POP _Pragma("clang diagnostic pop")
+# define _LIBCPP_CLANG_DIAGNOSTIC_IGNORED(str) _Pragma(_LIBCPP_TOSTRING(clang diagnostic ignored str))
+# define _LIBCPP_GCC_DIAGNOSTIC_IGNORED(str)
+# elif defined(_LIBCPP_COMPILER_GCC)
+# define _LIBCPP_DIAGNOSTIC_PUSH _Pragma("GCC diagnostic push")
+# define _LIBCPP_DIAGNOSTIC_POP _Pragma("GCC diagnostic pop")
+# define _LIBCPP_CLANG_DIAGNOSTIC_IGNORED(str)
+# define _LIBCPP_GCC_DIAGNOSTIC_IGNORED(str) _Pragma(_LIBCPP_TOSTRING(GCC diagnostic ignored str))
+# else
+# define _LIBCPP_DIAGNOSTIC_PUSH
+# define _LIBCPP_DIAGNOSTIC_POP
+# define _LIBCPP_CLANG_DIAGNOSTIC_IGNORED(str)
+# define _LIBCPP_GCC_DIAGNOSTIC_IGNORED(str)
+# endif
+
+# if _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_FAST
+# define _LIBCPP_HARDENING_SIG f
+# elif _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_EXTENSIVE
+# define _LIBCPP_HARDENING_SIG s
+# elif _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_DEBUG
+# define _LIBCPP_HARDENING_SIG d
+# else
+# define _LIBCPP_HARDENING_SIG n // "none"
+# endif
+
+# ifdef _LIBCPP_HAS_NO_EXCEPTIONS
+# define _LIBCPP_EXCEPTIONS_SIG n
+# else
+# define _LIBCPP_EXCEPTIONS_SIG e
+# endif
+
+# define _LIBCPP_ODR_SIGNATURE \
+ _LIBCPP_CONCAT(_LIBCPP_CONCAT(_LIBCPP_HARDENING_SIG, _LIBCPP_EXCEPTIONS_SIG), _LIBCPP_VERSION)
+
+// This macro marks a symbol as being hidden from libc++'s ABI. This is achieved
+// on two levels:
+// 1. The symbol is given hidden visibility, which ensures that users won't start exporting
+// symbols from their dynamic library by means of using the libc++ headers. This ensures
+// that those symbols stay private to the dynamic library in which it is defined.
+//
+// 2. The symbol is given an ABI tag that encodes the ODR-relevant properties of the library.
+// This ensures that no ODR violation can arise from mixing two TUs compiled with different
+// versions or configurations of libc++ (such as exceptions vs no-exceptions). Indeed, if the
+// program contains two definitions of a function, the ODR requires them to be token-by-token
+// equivalent, and the linker is allowed to pick either definition and discard the other one.
+//
+// For example, if a program contains a copy of `vector::at()` compiled with exceptions enabled
+// *and* a copy of `vector::at()` compiled with exceptions disabled (by means of having two TUs
+// compiled with different settings), the two definitions are both visible by the linker and they
+// have the same name, but they have a meaningfully different implementation (one throws an exception
+// and the other aborts the program). This violates the ODR and makes the program ill-formed, and in
+// practice what will happen is that the linker will pick one of the definitions at random and will
+// discard the other one. This can quite clearly lead to incorrect program behavior.
+//
+// A similar reasoning holds for many other properties that are ODR-affecting. Essentially any
+// property that causes the code of a function to differ from the code in another configuration
+// can be considered ODR-affecting. In practice, we don't encode all such properties in the ABI
+// tag, but we encode the ones that we think are most important: library version, exceptions, and
+// hardening mode.
+//
+// Note that historically, solving this problem has been achieved in various ways, including
+// force-inlining all functions or giving internal linkage to all functions. Both these previous
+// solutions suffer from drawbacks that lead notably to code bloat.
+//
+// Note that we use _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION to ensure that we don't depend
+// on _LIBCPP_HIDE_FROM_ABI methods of classes explicitly instantiated in the dynamic library.
+//
+// Also note that the _LIBCPP_HIDE_FROM_ABI_VIRTUAL macro should be used on virtual functions
+// instead of _LIBCPP_HIDE_FROM_ABI. That macro does not use an ABI tag. Indeed, the mangled
+// name of a virtual function is part of its ABI, since some architectures like arm64e can sign
+// the virtual function pointer in the vtable based on the mangled name of the function. Since
+// we use an ABI tag that changes with each released version, the mangled name of the virtual
+// function would change, which is incorrect. Note that it doesn't make much sense to change
+// the implementation of a virtual function in an ABI-incompatible way in the first place,
+// since that would be an ABI break anyway. Hence, the lack of ABI tag should not be noticeable.
+//
+// The macro can be applied to record and enum types. When the tagged type is nested in
+// a record this "parent" record needs to have the macro too. Another use case for applying
+// this macro to records and unions is to apply an ABI tag to inline constexpr variables.
+// This can be useful for inline variables that are implementation details which are expected
+// to change in the future.
+//
+// TODO: We provide a escape hatch with _LIBCPP_NO_ABI_TAG for folks who want to avoid increasing
+// the length of symbols with an ABI tag. In practice, we should remove the escape hatch and
+// use compression mangling instead, see https://github.com/itanium-cxx-abi/cxx-abi/issues/70.
+# ifndef _LIBCPP_NO_ABI_TAG
+# define _LIBCPP_HIDE_FROM_ABI \
+ _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION \
+ __attribute__((__abi_tag__(_LIBCPP_TOSTRING(_LIBCPP_ODR_SIGNATURE))))
+# else
+# define _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION
+# endif
+# define _LIBCPP_HIDE_FROM_ABI_VIRTUAL _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION
+
+# ifdef _LIBCPP_BUILDING_LIBRARY
+# if _LIBCPP_ABI_VERSION > 1
+# define _LIBCPP_HIDE_FROM_ABI_AFTER_V1 _LIBCPP_HIDE_FROM_ABI
+# else
+# define _LIBCPP_HIDE_FROM_ABI_AFTER_V1
+# endif
+# else
+# define _LIBCPP_HIDE_FROM_ABI_AFTER_V1 _LIBCPP_HIDE_FROM_ABI
+# endif
+
+// TODO: Remove this workaround once we drop support for Clang 16
+# if __has_warning("-Wc++23-extensions")
+# define _LIBCPP_CLANG_DIAGNOSTIC_IGNORED_CXX23_EXTENSION _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++23-extensions")
+# else
+# define _LIBCPP_CLANG_DIAGNOSTIC_IGNORED_CXX23_EXTENSION _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++2b-extensions")
+# endif
+
+// Clang modules take a significant compile time hit when pushing and popping diagnostics.
+// Since all the headers are marked as system headers in the modulemap, we can simply disable this
+// pushing and popping when building with clang modules.
+# if !__has_feature(modules)
+# define _LIBCPP_PUSH_EXTENSION_DIAGNOSTICS \
+ _LIBCPP_DIAGNOSTIC_PUSH \
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++11-extensions") \
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++14-extensions") \
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++17-extensions") \
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++20-extensions") \
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED_CXX23_EXTENSION \
+ _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wc++14-extensions") \
+ _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wc++17-extensions") \
+ _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wc++20-extensions") \
+ _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wc++23-extensions")
+# define _LIBCPP_POP_EXTENSION_DIAGNOSTICS _LIBCPP_DIAGNOSTIC_POP
+# else
+# define _LIBCPP_PUSH_EXTENSION_DIAGNOSTICS
+# define _LIBCPP_POP_EXTENSION_DIAGNOSTICS
+# endif
+
+// Inline namespaces are available in Clang/GCC/MSVC regardless of C++ dialect.
+// clang-format off
+# define _LIBCPP_BEGIN_NAMESPACE_STD _LIBCPP_PUSH_EXTENSION_DIAGNOSTICS \
+ namespace _LIBCPP_TYPE_VISIBILITY_DEFAULT std { \
+ inline namespace _LIBCPP_ABI_NAMESPACE {
+# define _LIBCPP_END_NAMESPACE_STD }} _LIBCPP_POP_EXTENSION_DIAGNOSTICS
+
+#ifdef _LIBCPP_ABI_NO_FILESYSTEM_INLINE_NAMESPACE
+# define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM _LIBCPP_BEGIN_NAMESPACE_STD namespace filesystem {
+# define _LIBCPP_END_NAMESPACE_FILESYSTEM } _LIBCPP_END_NAMESPACE_STD
+#else
+# define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM _LIBCPP_BEGIN_NAMESPACE_STD \
+ inline namespace __fs { namespace filesystem {
+
+# define _LIBCPP_END_NAMESPACE_FILESYSTEM }} _LIBCPP_END_NAMESPACE_STD
+#endif
+
+// clang-format on
+
+# if __has_attribute(__enable_if__)
+# define _LIBCPP_PREFERRED_OVERLOAD __attribute__((__enable_if__(true, "")))
+# endif
+
+# if !defined(__SIZEOF_INT128__) || defined(_MSC_VER)
+# define _LIBCPP_HAS_NO_INT128
+# endif
+
+# ifdef _LIBCPP_CXX03_LANG
+# define _LIBCPP_DECLARE_STRONG_ENUM(x) \
+ struct _LIBCPP_EXPORTED_FROM_ABI x { \
+ enum __lx
+// clang-format off
+# define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x) \
+ __lx __v_; \
+ _LIBCPP_HIDE_FROM_ABI x(__lx __v) : __v_(__v) {} \
+ _LIBCPP_HIDE_FROM_ABI explicit x(int __v) : __v_(static_cast<__lx>(__v)) {} \
+ _LIBCPP_HIDE_FROM_ABI operator int() const { return __v_; } \
+ };
+// clang-format on
+
+# else // _LIBCPP_CXX03_LANG
+# define _LIBCPP_DECLARE_STRONG_ENUM(x) enum class x
+# define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x)
+# endif // _LIBCPP_CXX03_LANG
+
+# if defined(__APPLE__) || defined(__FreeBSD__) || defined(_LIBCPP_MSVCRT_LIKE) || defined(__NetBSD__)
+# define _LIBCPP_LOCALE__L_EXTENSIONS 1
+# endif
+
+# ifdef __FreeBSD__
+# define _DECLARE_C99_LDBL_MATH 1
+# endif
+
+// If we are getting operator new from the MSVC CRT, then allocation overloads
+// for align_val_t were added in 19.12, aka VS 2017 version 15.3.
+# if defined(_LIBCPP_MSVCRT) && defined(_MSC_VER) && _MSC_VER < 1912
+# define _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
+# elif defined(_LIBCPP_ABI_VCRUNTIME) && !defined(__cpp_aligned_new)
+// We're deferring to Microsoft's STL to provide aligned new et al. We don't
+// have it unless the language feature test macro is defined.
+# define _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
+# elif defined(__MVS__)
+# define _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
+# endif
+
+# if defined(_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION) || (!defined(__cpp_aligned_new) || __cpp_aligned_new < 201606)
+# define _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
+# endif
+
+// It is not yet possible to use aligned_alloc() on all Apple platforms since
+// 10.15 was the first version to ship an implementation of aligned_alloc().
+# if defined(__APPLE__)
+# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \
+ __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101500)
+# define _LIBCPP_HAS_NO_C11_ALIGNED_ALLOC
+# endif
+# elif defined(__ANDROID__) && __ANDROID_API__ < 28
+// Android only provides aligned_alloc when targeting API 28 or higher.
+# define _LIBCPP_HAS_NO_C11_ALIGNED_ALLOC
+# endif
+
+# if defined(__APPLE__) || defined(__FreeBSD__)
+# define _LIBCPP_HAS_DEFAULTRUNELOCALE
+# endif
+
+# if defined(__APPLE__) || defined(__FreeBSD__)
+# define _LIBCPP_WCTYPE_IS_MASK
+# endif
+
+# if _LIBCPP_STD_VER <= 17 || !defined(__cpp_char8_t)
+# define _LIBCPP_HAS_NO_CHAR8_T
+# endif
+
+// Deprecation macros.
+//
+// Deprecations warnings are always enabled, except when users explicitly opt-out
+// by defining _LIBCPP_DISABLE_DEPRECATION_WARNINGS.
+# if !defined(_LIBCPP_DISABLE_DEPRECATION_WARNINGS)
+# if __has_attribute(__deprecated__)
+# define _LIBCPP_DEPRECATED __attribute__((__deprecated__))
+# define _LIBCPP_DEPRECATED_(m) __attribute__((__deprecated__(m)))
+# elif _LIBCPP_STD_VER >= 14
+# define _LIBCPP_DEPRECATED [[deprecated]]
+# define _LIBCPP_DEPRECATED_(m) [[deprecated(m)]]
+# else
+# define _LIBCPP_DEPRECATED
+# define _LIBCPP_DEPRECATED_(m)
+# endif
+# else
+# define _LIBCPP_DEPRECATED
+# define _LIBCPP_DEPRECATED_(m)
+# endif
+
+# if _LIBCPP_STD_VER < 20
+# define _LIBCPP_DEPRECATED_ATOMIC_SYNC \
+ _LIBCPP_DEPRECATED_("The C++20 synchronization library has been deprecated prior to C++20. Please update to " \
+ "using -std=c++20 if you need to use these facilities.")
+# else
+# define _LIBCPP_DEPRECATED_ATOMIC_SYNC /* nothing */
+# endif
+
+# if !defined(_LIBCPP_CXX03_LANG)
+# define _LIBCPP_DEPRECATED_IN_CXX11 _LIBCPP_DEPRECATED
+# else
+# define _LIBCPP_DEPRECATED_IN_CXX11
+# endif
+
+# if _LIBCPP_STD_VER >= 14
+# define _LIBCPP_DEPRECATED_IN_CXX14 _LIBCPP_DEPRECATED
+# else
+# define _LIBCPP_DEPRECATED_IN_CXX14
+# endif
+
+# if _LIBCPP_STD_VER >= 17
+# define _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_DEPRECATED
+# else
+# define _LIBCPP_DEPRECATED_IN_CXX17
+# endif
+
+# if _LIBCPP_STD_VER >= 20
+# define _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_DEPRECATED
+# else
+# define _LIBCPP_DEPRECATED_IN_CXX20
+# endif
+
+# if _LIBCPP_STD_VER >= 23
+# define _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_DEPRECATED
+# else
+# define _LIBCPP_DEPRECATED_IN_CXX23
+# endif
+
+# if _LIBCPP_STD_VER >= 26
+# define _LIBCPP_DEPRECATED_IN_CXX26 _LIBCPP_DEPRECATED
+# else
+# define _LIBCPP_DEPRECATED_IN_CXX26
+# endif
+
+# if !defined(_LIBCPP_HAS_NO_CHAR8_T)
+# define _LIBCPP_DEPRECATED_WITH_CHAR8_T _LIBCPP_DEPRECATED
+# else
+# define _LIBCPP_DEPRECATED_WITH_CHAR8_T
+# endif
+
+// Macros to enter and leave a state where deprecation warnings are suppressed.
+# if defined(_LIBCPP_COMPILER_CLANG_BASED) || defined(_LIBCPP_COMPILER_GCC)
+# define _LIBCPP_SUPPRESS_DEPRECATED_PUSH \
+ _Pragma("GCC diagnostic push") _Pragma("GCC diagnostic ignored \"-Wdeprecated\"") \
+ _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
+# define _LIBCPP_SUPPRESS_DEPRECATED_POP _Pragma("GCC diagnostic pop")
+# else
+# define _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+# define _LIBCPP_SUPPRESS_DEPRECATED_POP
+# endif
+
+# if _LIBCPP_STD_VER <= 11
+# define _LIBCPP_EXPLICIT_SINCE_CXX14
+# else
+# define _LIBCPP_EXPLICIT_SINCE_CXX14 explicit
+# endif
+
+# if _LIBCPP_STD_VER >= 23
+# define _LIBCPP_EXPLICIT_SINCE_CXX23 explicit
+# else
+# define _LIBCPP_EXPLICIT_SINCE_CXX23
+# endif
+
+# if _LIBCPP_STD_VER >= 14
+# define _LIBCPP_CONSTEXPR_SINCE_CXX14 constexpr
+# else
+# define _LIBCPP_CONSTEXPR_SINCE_CXX14
+# endif
+
+# if _LIBCPP_STD_VER >= 17
+# define _LIBCPP_CONSTEXPR_SINCE_CXX17 constexpr
+# else
+# define _LIBCPP_CONSTEXPR_SINCE_CXX17
+# endif
+
+# if _LIBCPP_STD_VER >= 20
+# define _LIBCPP_CONSTEXPR_SINCE_CXX20 constexpr
+# else
+# define _LIBCPP_CONSTEXPR_SINCE_CXX20
+# endif
+
+# if _LIBCPP_STD_VER >= 23
+# define _LIBCPP_CONSTEXPR_SINCE_CXX23 constexpr
+# else
+# define _LIBCPP_CONSTEXPR_SINCE_CXX23
+# endif
+
+# ifndef _LIBCPP_WEAK
+# define _LIBCPP_WEAK __attribute__((__weak__))
+# endif
+
+// Thread API
+// clang-format off
+# if !defined(_LIBCPP_HAS_NO_THREADS) && \
+ !defined(_LIBCPP_HAS_THREAD_API_PTHREAD) && \
+ !defined(_LIBCPP_HAS_THREAD_API_WIN32) && \
+ !defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
+
+# if defined(__FreeBSD__) || \
+ defined(__wasi__) || \
+ defined(__NetBSD__) || \
+ defined(__OpenBSD__) || \
+ defined(__NuttX__) || \
+ defined(__linux__) || \
+ defined(__GNU__) || \
+ defined(__APPLE__) || \
+ defined(__MVS__) || \
+ defined(_AIX) || \
+ defined(__EMSCRIPTEN__)
+// clang-format on
+# define _LIBCPP_HAS_THREAD_API_PTHREAD
+# elif defined(__Fuchsia__)
+// TODO(44575): Switch to C11 thread API when possible.
+# define _LIBCPP_HAS_THREAD_API_PTHREAD
+# elif defined(_LIBCPP_WIN32API)
+# define _LIBCPP_HAS_THREAD_API_WIN32
+# else
+# error "No thread API"
+# endif // _LIBCPP_HAS_THREAD_API
+# endif // _LIBCPP_HAS_NO_THREADS
+
+# if defined(_LIBCPP_HAS_THREAD_API_PTHREAD)
+# if defined(__ANDROID__) && __ANDROID_API__ >= 30
+# define _LIBCPP_HAS_COND_CLOCKWAIT
+# elif defined(_LIBCPP_GLIBC_PREREQ)
+# if _LIBCPP_GLIBC_PREREQ(2, 30)
+# define _LIBCPP_HAS_COND_CLOCKWAIT
+# endif
+# endif
+# endif
+
+# if defined(_LIBCPP_HAS_NO_THREADS) && defined(_LIBCPP_HAS_THREAD_API_PTHREAD)
+# error _LIBCPP_HAS_THREAD_API_PTHREAD may only be defined when \
+ _LIBCPP_HAS_NO_THREADS is not defined.
+# endif
+
+# if defined(_LIBCPP_HAS_NO_THREADS) && defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
+# error _LIBCPP_HAS_THREAD_API_EXTERNAL may not be defined when \
+ _LIBCPP_HAS_NO_THREADS is defined.
+# endif
+
+# if defined(_LIBCPP_HAS_NO_MONOTONIC_CLOCK) && !defined(_LIBCPP_HAS_NO_THREADS)
+# error _LIBCPP_HAS_NO_MONOTONIC_CLOCK may only be defined when \
+ _LIBCPP_HAS_NO_THREADS is defined.
+# endif
+
+# if !defined(_LIBCPP_HAS_NO_THREADS) && !defined(__STDCPP_THREADS__)
+# define __STDCPP_THREADS__ 1
+# endif
+
+// The glibc and Bionic implementation of pthreads implements
+// pthread_mutex_destroy as nop for regular mutexes. Additionally, Win32
+// mutexes have no destroy mechanism.
+//
+// This optimization can't be performed on Apple platforms, where
+// pthread_mutex_destroy can allow the kernel to release resources.
+// See https://llvm.org/D64298 for details.
+//
+// TODO(EricWF): Enable this optimization on Bionic after speaking to their
+// respective stakeholders.
+// clang-format off
+# if (defined(_LIBCPP_HAS_THREAD_API_PTHREAD) && defined(__GLIBC__)) || \
+ (defined(_LIBCPP_HAS_THREAD_API_C11) && defined(__Fuchsia__)) || \
+ defined(_LIBCPP_HAS_THREAD_API_WIN32)
+// clang-format on
+# define _LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION
+# endif
+
+// Destroying a condvar is a nop on Windows.
+//
+// This optimization can't be performed on Apple platforms, where
+// pthread_cond_destroy can allow the kernel to release resources.
+// See https://llvm.org/D64298 for details.
+//
+// TODO(EricWF): This is potentially true for some pthread implementations
+// as well.
+# if (defined(_LIBCPP_HAS_THREAD_API_C11) && defined(__Fuchsia__)) || defined(_LIBCPP_HAS_THREAD_API_WIN32)
+# define _LIBCPP_HAS_TRIVIAL_CONDVAR_DESTRUCTION
+# endif
+
+# if defined(__BIONIC__) || defined(__NuttX__) || defined(__Fuchsia__) || defined(__wasi__) || \
+ defined(_LIBCPP_HAS_MUSL_LIBC) || defined(__OpenBSD__)
+# define _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE
+# endif
+
+# if __has_feature(cxx_atomic) || __has_extension(c_atomic) || __has_keyword(_Atomic)
+# define _LIBCPP_HAS_C_ATOMIC_IMP
+# elif defined(_LIBCPP_COMPILER_GCC)
+# define _LIBCPP_HAS_GCC_ATOMIC_IMP
+# endif
+
+# if !defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_GCC_ATOMIC_IMP) && \
+ !defined(_LIBCPP_HAS_EXTERNAL_ATOMIC_IMP)
+# define _LIBCPP_HAS_NO_ATOMIC_HEADER
+# else
+# ifndef _LIBCPP_ATOMIC_FLAG_TYPE
+# define _LIBCPP_ATOMIC_FLAG_TYPE bool
+# endif
+# endif
+
+# if defined(__FreeBSD__) && defined(__clang__) && __has_attribute(__no_thread_safety_analysis__)
+# define _LIBCPP_NO_THREAD_SAFETY_ANALYSIS __attribute__((__no_thread_safety_analysis__))
+# else
+# define _LIBCPP_NO_THREAD_SAFETY_ANALYSIS
+# endif
+
+# if defined(_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS)
+# if defined(__clang__) && __has_attribute(acquire_capability)
+// Work around the attribute handling in clang. When both __declspec and
+// __attribute__ are present, the processing goes awry preventing the definition
+// of the types. In MinGW mode, __declspec evaluates to __attribute__, and thus
+// combining the two does work.
+# if !defined(_MSC_VER)
+# define _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS
+# endif
+# endif
+# endif
+
+# ifdef _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS
+# define _LIBCPP_THREAD_SAFETY_ANNOTATION(x) __attribute__((x))
+# else
+# define _LIBCPP_THREAD_SAFETY_ANNOTATION(x)
+# endif
+
+# if _LIBCPP_STD_VER >= 20
+# define _LIBCPP_CONSTINIT constinit
+# elif __has_attribute(__require_constant_initialization__)
+# define _LIBCPP_CONSTINIT __attribute__((__require_constant_initialization__))
+# else
+# define _LIBCPP_CONSTINIT
+# endif
+
+# if defined(__CUDACC__) || defined(__CUDA_ARCH__) || defined(__CUDA_LIBDEVICE__)
+// The CUDA SDK contains an unfortunate definition for the __noinline__ macro,
+// which breaks the regular __attribute__((__noinline__)) syntax. Therefore,
+// when compiling for CUDA we use the non-underscored version of the noinline
+// attribute.
+//
+// This is a temporary workaround and we still expect the CUDA SDK team to solve
+// this issue properly in the SDK headers.
+//
+// See https://github.com/llvm/llvm-project/pull/73838 for more details.
+# define _LIBCPP_NOINLINE __attribute__((noinline))
+# elif __has_attribute(__noinline__)
+# define _LIBCPP_NOINLINE __attribute__((__noinline__))
+# else
+# define _LIBCPP_NOINLINE
+# endif
+
+// We often repeat things just for handling wide characters in the library.
+// When wide characters are disabled, it can be useful to have a quick way of
+// disabling it without having to resort to #if-#endif, which has a larger
+// impact on readability.
+# if defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+# define _LIBCPP_IF_WIDE_CHARACTERS(...)
+# else
+# define _LIBCPP_IF_WIDE_CHARACTERS(...) __VA_ARGS__
+# endif
+
+// clang-format off
+# define _LIBCPP_PUSH_MACROS _Pragma("push_macro(\"min\")") _Pragma("push_macro(\"max\")") _Pragma("push_macro(\"refresh\")") _Pragma("push_macro(\"move\")") _Pragma("push_macro(\"erase\")")
+# define _LIBCPP_POP_MACROS _Pragma("pop_macro(\"min\")") _Pragma("pop_macro(\"max\")") _Pragma("pop_macro(\"refresh\")") _Pragma("pop_macro(\"move\")") _Pragma("pop_macro(\"erase\")")
+// clang-format on
+
+# ifndef _LIBCPP_NO_AUTO_LINK
+# if defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_BUILDING_LIBRARY)
+# if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+# pragma comment(lib, "c++.lib")
+# else
+# pragma comment(lib, "libc++.lib")
+# endif
+# endif // defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_BUILDING_LIBRARY)
+# endif // _LIBCPP_NO_AUTO_LINK
+
+// Configures the fopen close-on-exec mode character, if any. This string will
+// be appended to any mode string used by fstream for fopen/fdopen.
+//
+// Not all platforms support this, but it helps avoid fd-leaks on platforms that
+// do.
+# if defined(__BIONIC__)
+# define _LIBCPP_FOPEN_CLOEXEC_MODE "e"
+# else
+# define _LIBCPP_FOPEN_CLOEXEC_MODE
+# endif
+
+# if __has_cpp_attribute(msvc::no_unique_address)
+// MSVC implements [[no_unique_address]] as a silent no-op currently.
+// (If/when MSVC breaks its C++ ABI, it will be changed to work as intended.)
+// However, MSVC implements [[msvc::no_unique_address]] which does what
+// [[no_unique_address]] is supposed to do, in general.
+
+// Clang-cl does not yet (14.0) implement either [[no_unique_address]] or
+// [[msvc::no_unique_address]] though. If/when it does implement
+// [[msvc::no_unique_address]], this should be preferred though.
+# define _LIBCPP_NO_UNIQUE_ADDRESS [[msvc::no_unique_address]]
+# elif __has_cpp_attribute(no_unique_address)
+# define _LIBCPP_NO_UNIQUE_ADDRESS [[__no_unique_address__]]
+# else
+# define _LIBCPP_NO_UNIQUE_ADDRESS /* nothing */
+// Note that this can be replaced by #error as soon as clang-cl
+// implements msvc::no_unique_address, since there should be no C++20
+// compiler that doesn't support one of the two attributes at that point.
+// We generally don't want to use this macro outside of C++20-only code,
+// because using it conditionally in one language version only would make
+// the ABI inconsistent.
+# endif
+
+// c8rtomb() and mbrtoc8() were added in C++20 and C23. Support for these
+// functions is gradually being added to existing C libraries. The conditions
+// below check for known C library versions and conditions under which these
+// functions are declared by the C library.
+# define _LIBCPP_HAS_NO_C8RTOMB_MBRTOC8
+// GNU libc 2.36 and newer declare c8rtomb() and mbrtoc8() in C++ modes if
+// __cpp_char8_t is defined or if C2X extensions are enabled. Determining
+// the latter depends on internal GNU libc details that are not appropriate
+// to depend on here, so any declarations present when __cpp_char8_t is not
+// defined are ignored.
+# if defined(_LIBCPP_GLIBC_PREREQ)
+# if _LIBCPP_GLIBC_PREREQ(2, 36) && defined(__cpp_char8_t)
+# undef _LIBCPP_HAS_NO_C8RTOMB_MBRTOC8
+# endif
+# endif
+
+// There are a handful of public standard library types that are intended to
+// support CTAD but don't need any explicit deduction guides to do so. This
+// macro is used to mark them as such, which suppresses the
+// '-Wctad-maybe-unsupported' compiler warning when CTAD is used in user code
+// with these classes.
+# if _LIBCPP_STD_VER >= 17
+# ifdef _LIBCPP_COMPILER_CLANG_BASED
+# define _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(_ClassName) \
+ template <class... _Tag> \
+ [[maybe_unused]] _ClassName(typename _Tag::__allow_ctad...)->_ClassName<_Tag...>
+# else
+# define _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(ClassName) \
+ template <class... _Tag> \
+ ClassName(typename _Tag::__allow_ctad...)->ClassName<_Tag...>
+# endif
+# else
+# define _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(_ClassName) static_assert(true, "")
+# endif
+
+// TODO(varconst): currently, there are bugs in Clang's intrinsics when handling Objective-C++ `id`, so don't use
+// compiler intrinsics in the Objective-C++ mode.
+# ifdef __OBJC__
+# define _LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS
+# endif
+
+# define _PSTL_PRAGMA(x) _Pragma(#x)
+
+// Enable SIMD for compilers that support OpenMP 4.0
+# if (defined(_OPENMP) && _OPENMP >= 201307)
+
+# define _PSTL_UDR_PRESENT
+# define _PSTL_PRAGMA_SIMD _PSTL_PRAGMA(omp simd)
+# define _PSTL_PRAGMA_DECLARE_SIMD _PSTL_PRAGMA(omp declare simd)
+# define _PSTL_PRAGMA_SIMD_REDUCTION(PRM) _PSTL_PRAGMA(omp simd reduction(PRM))
+# define _PSTL_PRAGMA_SIMD_SCAN(PRM) _PSTL_PRAGMA(omp simd reduction(inscan, PRM))
+# define _PSTL_PRAGMA_SIMD_INCLUSIVE_SCAN(PRM) _PSTL_PRAGMA(omp scan inclusive(PRM))
+# define _PSTL_PRAGMA_SIMD_EXCLUSIVE_SCAN(PRM) _PSTL_PRAGMA(omp scan exclusive(PRM))
+
+// Declaration of reduction functor, where
+// NAME - the name of the functor
+// OP - type of the callable object with the reduction operation
+// omp_in - refers to the local partial result
+// omp_out - refers to the final value of the combiner operator
+// omp_priv - refers to the private copy of the initial value
+// omp_orig - refers to the original variable to be reduced
+# define _PSTL_PRAGMA_DECLARE_REDUCTION(NAME, OP) \
+ _PSTL_PRAGMA(omp declare reduction(NAME:OP : omp_out(omp_in)) initializer(omp_priv = omp_orig))
+
+# elif defined(_LIBCPP_COMPILER_CLANG_BASED)
+
+# define _PSTL_PRAGMA_SIMD _Pragma("clang loop vectorize(enable) interleave(enable)")
+# define _PSTL_PRAGMA_DECLARE_SIMD
+# define _PSTL_PRAGMA_SIMD_REDUCTION(PRM) _Pragma("clang loop vectorize(enable) interleave(enable)")
+# define _PSTL_PRAGMA_SIMD_SCAN(PRM) _Pragma("clang loop vectorize(enable) interleave(enable)")
+# define _PSTL_PRAGMA_SIMD_INCLUSIVE_SCAN(PRM)
+# define _PSTL_PRAGMA_SIMD_EXCLUSIVE_SCAN(PRM)
+# define _PSTL_PRAGMA_DECLARE_REDUCTION(NAME, OP)
+
+# else // (defined(_OPENMP) && _OPENMP >= 201307)
+
+# define _PSTL_PRAGMA_SIMD
+# define _PSTL_PRAGMA_DECLARE_SIMD
+# define _PSTL_PRAGMA_SIMD_REDUCTION(PRM)
+# define _PSTL_PRAGMA_SIMD_SCAN(PRM)
+# define _PSTL_PRAGMA_SIMD_INCLUSIVE_SCAN(PRM)
+# define _PSTL_PRAGMA_SIMD_EXCLUSIVE_SCAN(PRM)
+# define _PSTL_PRAGMA_DECLARE_REDUCTION(NAME, OP)
+
+# endif // (defined(_OPENMP) && _OPENMP >= 201307)
+
+# define _PSTL_USE_NONTEMPORAL_STORES_IF_ALLOWED
+
+// Optional attributes - these are useful for a better QoI, but not required to be available
+
+# if __has_attribute(__no_sanitize__) && !defined(_LIBCPP_COMPILER_GCC)
+# define _LIBCPP_NO_CFI __attribute__((__no_sanitize__("cfi")))
+# else
+# define _LIBCPP_NO_CFI
+# endif
+
+# if __has_attribute(__malloc__)
+# define _LIBCPP_NOALIAS __attribute__((__malloc__))
+# else
+# define _LIBCPP_NOALIAS
+# endif
+
+# if __has_attribute(__using_if_exists__)
+# define _LIBCPP_USING_IF_EXISTS __attribute__((__using_if_exists__))
+# else
+# define _LIBCPP_USING_IF_EXISTS
+# endif
+
+# if __has_cpp_attribute(__nodiscard__)
+# define _LIBCPP_NODISCARD [[__nodiscard__]]
+# else
+// We can't use GCC's [[gnu::warn_unused_result]] and
+// __attribute__((warn_unused_result)), because GCC does not silence them via
+// (void) cast.
+# define _LIBCPP_NODISCARD
+# endif
+
+# if __has_attribute(__no_destroy__)
+# define _LIBCPP_NO_DESTROY __attribute__((__no_destroy__))
+# else
+# define _LIBCPP_NO_DESTROY
+# endif
+
+# if __has_attribute(__diagnose_if__)
+# define _LIBCPP_DIAGNOSE_WARNING(...) __attribute__((__diagnose_if__(__VA_ARGS__, "warning")))
+# else
+# define _LIBCPP_DIAGNOSE_WARNING(...)
+# endif
+
+// Use a function like macro to imply that it must be followed by a semicolon
+# if __has_cpp_attribute(fallthrough)
+# define _LIBCPP_FALLTHROUGH() [[fallthrough]]
+# elif __has_attribute(__fallthrough__)
+# define _LIBCPP_FALLTHROUGH() __attribute__((__fallthrough__))
+# else
+# define _LIBCPP_FALLTHROUGH() ((void)0)
+# endif
+
+# if __has_cpp_attribute(_Clang::__lifetimebound__)
+# define _LIBCPP_LIFETIMEBOUND [[_Clang::__lifetimebound__]]
+# else
+# define _LIBCPP_LIFETIMEBOUND
+# endif
+
+# if __has_attribute(__nodebug__)
+# define _LIBCPP_NODEBUG __attribute__((__nodebug__))
+# else
+# define _LIBCPP_NODEBUG
+# endif
+
+# if __has_attribute(__standalone_debug__)
+# define _LIBCPP_STANDALONE_DEBUG __attribute__((__standalone_debug__))
+# else
+# define _LIBCPP_STANDALONE_DEBUG
+# endif
+
+# if __has_attribute(__preferred_name__)
+# define _LIBCPP_PREFERRED_NAME(x) __attribute__((__preferred_name__(x)))
+# else
+# define _LIBCPP_PREFERRED_NAME(x)
+# endif
+
+# if __has_attribute(__no_sanitize__)
+# define _LIBCPP_NO_SANITIZE(...) __attribute__((__no_sanitize__(__VA_ARGS__)))
+# else
+# define _LIBCPP_NO_SANITIZE(...)
+# endif
+
+# if __has_attribute(__init_priority__)
+# define _LIBCPP_INIT_PRIORITY_MAX __attribute__((__init_priority__(100)))
+# else
+# define _LIBCPP_INIT_PRIORITY_MAX
+# endif
+
+# if __has_attribute(__format__)
+// The attribute uses 1-based indices for ordinary and static member functions.
+// The attribute uses 2-based indices for non-static member functions.
+# define _LIBCPP_ATTRIBUTE_FORMAT(archetype, format_string_index, first_format_arg_index) \
+ __attribute__((__format__(archetype, format_string_index, first_format_arg_index)))
+# else
+# define _LIBCPP_ATTRIBUTE_FORMAT(archetype, format_string_index, first_format_arg_index) /* nothing */
+# endif
+
+# if __has_attribute(__packed__)
+# define _LIBCPP_PACKED __attribute__((__packed__))
+# else
+# define _LIBCPP_PACKED
+# endif
+
+# if defined(_LIBCPP_ABI_MICROSOFT) && __has_declspec_attribute(empty_bases)
+# define _LIBCPP_DECLSPEC_EMPTY_BASES __declspec(empty_bases)
+# else
+# define _LIBCPP_DECLSPEC_EMPTY_BASES
+# endif
+
+// Allow for build-time disabling of unsigned integer sanitization
+# if __has_attribute(no_sanitize) && !defined(_LIBCPP_COMPILER_GCC)
+# define _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK __attribute__((__no_sanitize__("unsigned-integer-overflow")))
+# else
+# define _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
+# endif
+
+// Clang-18 has support for deducing this, but it does not set the FTM.
+# if defined(__cpp_explicit_this_parameter) || (defined(_LIBCPP_CLANG_VER) && _LIBCPP_CLANG_VER >= 1800)
+# define _LIBCPP_HAS_EXPLICIT_THIS_PARAMETER
+# endif
+
+#endif // __cplusplus
+
+#endif // _LIBCPP___CONFIG
diff --git a/libcxx/include/__cxx03/__config_site.in b/libcxx/include/__cxx03/__config_site.in
new file mode 100644
index 00000000000000..67022146c9082b
--- /dev/null
+++ b/libcxx/include/__cxx03/__config_site.in
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONFIG_SITE
+#define _LIBCPP___CONFIG_SITE
+
+#cmakedefine _LIBCPP_ABI_VERSION @_LIBCPP_ABI_VERSION@
+#cmakedefine _LIBCPP_ABI_NAMESPACE @_LIBCPP_ABI_NAMESPACE@
+#cmakedefine _LIBCPP_ABI_FORCE_ITANIUM
+#cmakedefine _LIBCPP_ABI_FORCE_MICROSOFT
+#cmakedefine _LIBCPP_HAS_NO_THREADS
+#cmakedefine _LIBCPP_HAS_NO_MONOTONIC_CLOCK
+#cmakedefine _LIBCPP_HAS_MUSL_LIBC
+#cmakedefine _LIBCPP_HAS_THREAD_API_PTHREAD
+#cmakedefine _LIBCPP_HAS_THREAD_API_EXTERNAL
+#cmakedefine _LIBCPP_HAS_THREAD_API_WIN32
+#cmakedefine _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS
+#cmakedefine _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
+#cmakedefine _LIBCPP_NO_VCRUNTIME
+#cmakedefine _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION @_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION@
+#cmakedefine _LIBCPP_HAS_NO_FILESYSTEM
+#cmakedefine _LIBCPP_HAS_NO_RANDOM_DEVICE
+#cmakedefine _LIBCPP_HAS_NO_LOCALIZATION
+#cmakedefine _LIBCPP_HAS_NO_UNICODE
+#cmakedefine _LIBCPP_HAS_NO_WIDE_CHARACTERS
+#cmakedefine _LIBCPP_HAS_NO_STD_MODULES
+#cmakedefine _LIBCPP_HAS_NO_TIME_ZONE_DATABASE
+#cmakedefine _LIBCPP_INSTRUMENTED_WITH_ASAN
+
+// PSTL backends
+#cmakedefine _LIBCPP_PSTL_BACKEND_SERIAL
+#cmakedefine _LIBCPP_PSTL_BACKEND_STD_THREAD
+#cmakedefine _LIBCPP_PSTL_BACKEND_LIBDISPATCH
+
+// Hardening.
+#cmakedefine _LIBCPP_HARDENING_MODE_DEFAULT @_LIBCPP_HARDENING_MODE_DEFAULT@
+
+// __USE_MINGW_ANSI_STDIO gets redefined on MinGW
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wmacro-redefined"
+#endif
+
+ at _LIBCPP_ABI_DEFINES@
+ at _LIBCPP_EXTRA_SITE_DEFINES@
+
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+
+#endif // _LIBCPP___CONFIG_SITE
diff --git a/libcxx/include/__cxx03/__configuration/abi.h b/libcxx/include/__cxx03/__configuration/abi.h
new file mode 100644
index 00000000000000..0422b645727d8a
--- /dev/null
+++ b/libcxx/include/__cxx03/__configuration/abi.h
@@ -0,0 +1,172 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONFIGURATION_ABI_H
+#define _LIBCPP___CONFIGURATION_ABI_H
+
+#include <__config_site>
+#include <__configuration/compiler.h>
+#include <__configuration/platform.h>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_ABI_VERSION >= 2
+// Change short string representation so that string data starts at offset 0,
+// improving its alignment in some cases.
+# define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+// Fix deque iterator type in order to support incomplete types.
+# define _LIBCPP_ABI_INCOMPLETE_TYPES_IN_DEQUE
+// Fix undefined behavior in how std::list stores its linked nodes.
+# define _LIBCPP_ABI_LIST_REMOVE_NODE_POINTER_UB
+// Fix undefined behavior in how __tree stores its end and parent nodes.
+# define _LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB
+// Fix undefined behavior in how __hash_table stores its pointer types.
+# define _LIBCPP_ABI_FIX_UNORDERED_NODE_POINTER_UB
+# define _LIBCPP_ABI_FORWARD_LIST_REMOVE_NODE_POINTER_UB
+# define _LIBCPP_ABI_FIX_UNORDERED_CONTAINER_SIZE_TYPE
+// Override the default return value of exception::what() for bad_function_call::what()
+// with a string that is specific to bad_function_call (see http://wg21.link/LWG2233).
+// This is an ABI break on platforms that sign and authenticate vtable function pointers
+// because it changes the mangling of the virtual function located in the vtable, which
+// changes how it gets signed.
+# define _LIBCPP_ABI_BAD_FUNCTION_CALL_GOOD_WHAT_MESSAGE
+// Enable optimized version of __do_get_(un)signed which avoids redundant copies.
+# define _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
+// Give reverse_iterator<T> one data member of type T, not two.
+// Also, in C++17 and later, don't derive iterator types from std::iterator.
+# define _LIBCPP_ABI_NO_ITERATOR_BASES
+// Use the smallest possible integer type to represent the index of the variant.
+// Previously libc++ used "unsigned int" exclusively.
+# define _LIBCPP_ABI_VARIANT_INDEX_TYPE_OPTIMIZATION
+// Unstable attempt to provide a more optimized std::function
+# define _LIBCPP_ABI_OPTIMIZED_FUNCTION
+// All the regex constants must be distinct and nonzero.
+# define _LIBCPP_ABI_REGEX_CONSTANTS_NONZERO
+// Re-worked external template instantiations for std::string with a focus on
+// performance and fast-path inlining.
+# define _LIBCPP_ABI_STRING_OPTIMIZED_EXTERNAL_INSTANTIATION
+// Enable clang::trivial_abi on std::unique_ptr.
+# define _LIBCPP_ABI_ENABLE_UNIQUE_PTR_TRIVIAL_ABI
+// Enable clang::trivial_abi on std::shared_ptr and std::weak_ptr
+# define _LIBCPP_ABI_ENABLE_SHARED_PTR_TRIVIAL_ABI
+// std::random_device holds some state when it uses an implementation that gets
+// entropy from a file (see _LIBCPP_USING_DEV_RANDOM). When switching from this
+// implementation to another one on a platform that has already shipped
+// std::random_device, one needs to retain the same object layout to remain ABI
+// compatible. This switch removes these workarounds for platforms that don't care
+// about ABI compatibility.
+# define _LIBCPP_ABI_NO_RANDOM_DEVICE_COMPATIBILITY_LAYOUT
+// Don't export the legacy __basic_string_common class and its methods from the built library.
+# define _LIBCPP_ABI_DO_NOT_EXPORT_BASIC_STRING_COMMON
+// Don't export the legacy __vector_base_common class and its methods from the built library.
+# define _LIBCPP_ABI_DO_NOT_EXPORT_VECTOR_BASE_COMMON
+// According to the Standard, `bitset::operator[] const` returns bool
+# define _LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL
+// Fix the implementation of CityHash used for std::hash<fundamental-type>.
+// This is an ABI break because `std::hash` will return a different result,
+// which means that hashing the same object in translation units built against
+// different versions of libc++ can return inconsistent results. This is especially
+// tricky since std::hash is used in the implementation of unordered containers.
+//
+// The incorrect implementation of CityHash has the problem that it drops some
+// bits on the floor.
+# define _LIBCPP_ABI_FIX_CITYHASH_IMPLEMENTATION
+// Remove the base 10 implementation of std::to_chars from the dylib.
+// The implementation moved to the header, but we still export the symbols from
+// the dylib for backwards compatibility.
+# define _LIBCPP_ABI_DO_NOT_EXPORT_TO_CHARS_BASE_10
+// Define std::array/std::string_view iterators to be __wrap_iters instead of raw
+// pointers, which prevents people from relying on a non-portable implementation
+// detail. This is especially useful because enabling bounded iterators hardening
+// requires code not to make these assumptions.
+# define _LIBCPP_ABI_USE_WRAP_ITER_IN_STD_ARRAY
+# define _LIBCPP_ABI_USE_WRAP_ITER_IN_STD_STRING_VIEW
+// Dont' add an inline namespace for `std::filesystem`
+# define _LIBCPP_ABI_NO_FILESYSTEM_INLINE_NAMESPACE
+// std::basic_ios uses WEOF to indicate that the fill value is
+// uninitialized. However, on platforms where the size of char_type is
+// equal to or greater than the size of int_type and char_type is unsigned,
+// std::char_traits<char_type>::eq_int_type() cannot distinguish between WEOF
+// and WCHAR_MAX. This ABI setting determines whether we should instead track whether the fill
+// value has been initialized using a separate boolean, which changes the ABI.
+# define _LIBCPP_ABI_IOS_ALLOW_ARBITRARY_FILL_VALUE
+// Make a std::pair of trivially copyable types trivially copyable.
+// While this technically doesn't change the layout of pair itself, other types may decide to programatically change
+// their representation based on whether something is trivially copyable.
+# define _LIBCPP_ABI_TRIVIALLY_COPYABLE_PAIR
+#elif _LIBCPP_ABI_VERSION == 1
+# if !(defined(_LIBCPP_OBJECT_FORMAT_COFF) || defined(_LIBCPP_OBJECT_FORMAT_XCOFF))
+// Enable compiling copies of now inline methods into the dylib to support
+// applications compiled against older libraries. This is unnecessary with
+// COFF dllexport semantics, since dllexport forces a non-inline definition
+// of inline functions to be emitted anyway. Our own non-inline copy would
+// conflict with the dllexport-emitted copy, so we disable it. For XCOFF,
+// the linker will take issue with the symbols in the shared object if the
+// weak inline methods get visibility (such as from -fvisibility-inlines-hidden),
+// so disable it.
+# define _LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS
+# endif
+// Feature macros for disabling pre ABI v1 features. All of these options
+// are deprecated.
+# if defined(__FreeBSD__) && __FreeBSD__ < 14
+# define _LIBCPP_DEPRECATED_ABI_DISABLE_PAIR_TRIVIAL_COPY_CTOR
+# endif
+#endif
+
+// We had some bugs where we use [[no_unique_address]] together with construct_at,
+// which causes UB as the call on construct_at could write to overlapping subobjects
+//
+// https://github.com/llvm/llvm-project/issues/70506
+// https://github.com/llvm/llvm-project/issues/70494
+//
+// To fix the bug we had to change the ABI of some classes to remove [[no_unique_address]] under certain conditions.
+// The macro below is used for all classes whose ABI have changed as part of fixing these bugs.
+#define _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS __attribute__((__abi_tag__("llvm18_nua")))
+
+// Changes the iterator type of select containers (see below) to a bounded iterator that keeps track of whether it's
+// within the bounds of the original container and asserts it on every dereference.
+//
+// ABI impact: changes the iterator type of the relevant containers.
+//
+// Supported containers:
+// - `span`;
+// - `string_view`.
+// #define _LIBCPP_ABI_BOUNDED_ITERATORS
+
+// Changes the iterator type of `basic_string` to a bounded iterator that keeps track of whether it's within the bounds
+// of the original container and asserts it on every dereference and when performing iterator arithmetics.
+//
+// ABI impact: changes the iterator type of `basic_string` and its specializations, such as `string` and `wstring`.
+// #define _LIBCPP_ABI_BOUNDED_ITERATORS_IN_STRING
+
+// Changes the iterator type of `vector` to a bounded iterator that keeps track of whether it's within the bounds of the
+// original container and asserts it on every dereference and when performing iterator arithmetics. Note: this doesn't
+// yet affect `vector<bool>`.
+//
+// ABI impact: changes the iterator type of `vector` (except `vector<bool>`).
+// #define _LIBCPP_ABI_BOUNDED_ITERATORS_IN_VECTOR
+
+#if defined(_LIBCPP_COMPILER_CLANG_BASED)
+# if defined(__APPLE__)
+# if defined(__i386__) || defined(__x86_64__)
+// use old string layout on x86_64 and i386
+# elif defined(__arm__)
+// use old string layout on arm (which does not include aarch64/arm64), except on watch ABIs
+# if defined(__ARM_ARCH_7K__) && __ARM_ARCH_7K__ >= 2
+# define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+# endif
+# else
+# define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+# endif
+# endif
+#endif
+
+#endif // _LIBCPP___CONFIGURATION_ABI_H
diff --git a/libcxx/include/__cxx03/__configuration/availability.h b/libcxx/include/__cxx03/__configuration/availability.h
new file mode 100644
index 00000000000000..ab483a07c9c137
--- /dev/null
+++ b/libcxx/include/__cxx03/__configuration/availability.h
@@ -0,0 +1,400 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONFIGURATION_AVAILABILITY_H
+#define _LIBCPP___CONFIGURATION_AVAILABILITY_H
+
+#include <__configuration/compiler.h>
+#include <__configuration/language.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// Libc++ is shipped by various vendors. In particular, it is used as a system
+// library on macOS, iOS and other Apple platforms. In order for users to be
+// able to compile a binary that is intended to be deployed to an older version
+// of a platform, Clang provides availability attributes [1]. These attributes
+// can be placed on declarations and are used to describe the life cycle of a
+// symbol in the library.
+//
+// The main goal is to ensure a compile-time error if a symbol that hasn't been
+// introduced in a previously released library is used in a program that targets
+// that previously released library. Normally, this would be a load-time error
+// when one tries to launch the program against the older library.
+//
+// For example, the filesystem library was introduced in the dylib in LLVM 9.
+// On Apple platforms, this corresponds to macOS 10.15. If a user compiles on
+// a macOS 10.15 host but targets macOS 10.13 with their program, the compiler
+// would normally not complain (because the required declarations are in the
+// headers), but the dynamic loader would fail to find the symbols when actually
+// trying to launch the program on macOS 10.13. To turn this into a compile-time
+// issue instead, declarations are annotated with when they were introduced, and
+// the compiler can produce a diagnostic if the program references something that
+// isn't available on the deployment target.
+//
+// This mechanism is general in nature, and any vendor can add their markup to
+// the library (see below). Whenever a new feature is added that requires support
+// in the shared library, two macros are added below to allow marking the feature
+// as unavailable:
+// 1. A macro named `_LIBCPP_AVAILABILITY_HAS_<feature>` which must be defined
+// to `_LIBCPP_INTRODUCED_IN_<version>` for the appropriate LLVM version.
+// 2. A macro named `_LIBCPP_AVAILABILITY_<feature>`, which must be defined to
+// `_LIBCPP_INTRODUCED_IN_<version>_MARKUP` for the appropriate LLVM version.
+//
+// When vendors decide to ship the feature as part of their shared library, they
+// can update the `_LIBCPP_INTRODUCED_IN_<version>` macro (and the markup counterpart)
+// based on the platform version they shipped that version of LLVM in. The library
+// will then use this markup to provide an optimal user experience on these platforms.
+//
+// Furthermore, many features in the standard library have corresponding
+// feature-test macros. The `_LIBCPP_AVAILABILITY_HAS_<feature>` macros
+// are checked by the corresponding feature-test macros generated by
+// generate_feature_test_macro_components.py to ensure that the library
+// doesn't announce a feature as being implemented if it is unavailable on
+// the deployment target.
+//
+// Note that this mechanism is disabled by default in the "upstream" libc++.
+// Availability annotations are only meaningful when shipping libc++ inside
+// a platform (i.e. as a system library), and so vendors that want them should
+// turn those annotations on at CMake configuration time.
+//
+// [1]: https://clang.llvm.org/docs/AttributeReference.html#availability
+
+// For backwards compatibility, allow users to define _LIBCPP_DISABLE_AVAILABILITY
+// for a while.
+#if defined(_LIBCPP_DISABLE_AVAILABILITY)
+# if !defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
+# define _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
+# endif
+#endif
+
+// Availability markup is disabled when building the library, or when a non-Clang
+// compiler is used because only Clang supports the necessary attributes.
+#if defined(_LIBCPP_BUILDING_LIBRARY) || defined(_LIBCXXABI_BUILDING_LIBRARY) || !defined(_LIBCPP_COMPILER_CLANG_BASED)
+# if !defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
+# define _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
+# endif
+#endif
+
+// When availability annotations are disabled, we take for granted that features introduced
+// in all versions of the library are available.
+#if defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_19 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_18 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_18_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_17 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_17_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_16 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_16_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_15 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_15_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_14 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_14_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_13 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_13_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_12 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_12_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_11 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_11_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_10 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_10_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_9 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE /* nothing */
+# define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_PUSH /* nothing */
+# define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_POP /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_8 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_8_ATTRIBUTE /* nothing */
+
+# define _LIBCPP_INTRODUCED_IN_LLVM_4 1
+# define _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE /* nothing */
+
+#elif defined(__APPLE__)
+
+// clang-format off
+
+// LLVM 19
+// TODO: Fill this in
+# define _LIBCPP_INTRODUCED_IN_LLVM_19 0
+# define _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE __attribute__((unavailable))
+
+// LLVM 18
+// TODO: Fill this in
+# define _LIBCPP_INTRODUCED_IN_LLVM_18 0
+# define _LIBCPP_INTRODUCED_IN_LLVM_18_ATTRIBUTE __attribute__((unavailable))
+
+// LLVM 17
+# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 140400) || \
+ (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 170400) || \
+ (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 170400) || \
+ (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 100400)
+# define _LIBCPP_INTRODUCED_IN_LLVM_17 0
+# else
+# define _LIBCPP_INTRODUCED_IN_LLVM_17 1
+# endif
+# define _LIBCPP_INTRODUCED_IN_LLVM_17_ATTRIBUTE \
+ __attribute__((availability(macos, strict, introduced = 14.4))) \
+ __attribute__((availability(ios, strict, introduced = 17.4))) \
+ __attribute__((availability(tvos, strict, introduced = 17.4))) \
+ __attribute__((availability(watchos, strict, introduced = 10.4)))
+
+// LLVM 16
+# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 140000) || \
+ (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 170000) || \
+ (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 170000) || \
+ (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 100000)
+# define _LIBCPP_INTRODUCED_IN_LLVM_16 0
+# else
+# define _LIBCPP_INTRODUCED_IN_LLVM_16 1
+# endif
+# define _LIBCPP_INTRODUCED_IN_LLVM_16_ATTRIBUTE \
+ __attribute__((availability(macos, strict, introduced = 14.0))) \
+ __attribute__((availability(ios, strict, introduced = 17.0))) \
+ __attribute__((availability(tvos, strict, introduced = 17.0))) \
+ __attribute__((availability(watchos, strict, introduced = 10.0)))
+
+// LLVM 15
+# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 130400) || \
+ (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 160500) || \
+ (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 160500) || \
+ (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 90500)
+# define _LIBCPP_INTRODUCED_IN_LLVM_15 0
+# else
+# define _LIBCPP_INTRODUCED_IN_LLVM_15 1
+# endif
+# define _LIBCPP_INTRODUCED_IN_LLVM_15_ATTRIBUTE \
+ __attribute__((availability(macos, strict, introduced = 13.4))) \
+ __attribute__((availability(ios, strict, introduced = 16.5))) \
+ __attribute__((availability(tvos, strict, introduced = 16.5))) \
+ __attribute__((availability(watchos, strict, introduced = 9.5)))
+
+// LLVM 14
+# define _LIBCPP_INTRODUCED_IN_LLVM_14 _LIBCPP_INTRODUCED_IN_LLVM_15
+# define _LIBCPP_INTRODUCED_IN_LLVM_14_ATTRIBUTE _LIBCPP_INTRODUCED_IN_LLVM_15_ATTRIBUTE
+
+// LLVM 13
+# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 130000) || \
+ (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 160000) || \
+ (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 160000) || \
+ (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 90000)
+# define _LIBCPP_INTRODUCED_IN_LLVM_13 0
+# else
+# define _LIBCPP_INTRODUCED_IN_LLVM_13 1
+# endif
+# define _LIBCPP_INTRODUCED_IN_LLVM_13_ATTRIBUTE \
+ __attribute__((availability(macos, strict, introduced = 13.0))) \
+ __attribute__((availability(ios, strict, introduced = 16.0))) \
+ __attribute__((availability(tvos, strict, introduced = 16.0))) \
+ __attribute__((availability(watchos, strict, introduced = 9.0)))
+
+// LLVM 12
+# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 120300) || \
+ (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 150300) || \
+ (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 150300) || \
+ (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 80300)
+# define _LIBCPP_INTRODUCED_IN_LLVM_12 0
+# else
+# define _LIBCPP_INTRODUCED_IN_LLVM_12 1
+# endif
+# define _LIBCPP_INTRODUCED_IN_LLVM_12_ATTRIBUTE \
+ __attribute__((availability(macos, strict, introduced = 12.3))) \
+ __attribute__((availability(ios, strict, introduced = 15.3))) \
+ __attribute__((availability(tvos, strict, introduced = 15.3))) \
+ __attribute__((availability(watchos, strict, introduced = 8.3)))
+
+// LLVM 11
+# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 110000) || \
+ (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 140000) || \
+ (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 140000) || \
+ (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 70000)
+# define _LIBCPP_INTRODUCED_IN_LLVM_11 0
+# else
+# define _LIBCPP_INTRODUCED_IN_LLVM_11 1
+# endif
+# define _LIBCPP_INTRODUCED_IN_LLVM_11_ATTRIBUTE \
+ __attribute__((availability(macos, strict, introduced = 11.0))) \
+ __attribute__((availability(ios, strict, introduced = 14.0))) \
+ __attribute__((availability(tvos, strict, introduced = 14.0))) \
+ __attribute__((availability(watchos, strict, introduced = 7.0)))
+
+// LLVM 10
+# define _LIBCPP_INTRODUCED_IN_LLVM_10 _LIBCPP_INTRODUCED_IN_LLVM_11
+# define _LIBCPP_INTRODUCED_IN_LLVM_10_ATTRIBUTE _LIBCPP_INTRODUCED_IN_LLVM_11_ATTRIBUTE
+
+// LLVM 9
+# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101500) || \
+ (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 130000) || \
+ (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 130000) || \
+ (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 60000)
+# define _LIBCPP_INTRODUCED_IN_LLVM_9 0
+# else
+# define _LIBCPP_INTRODUCED_IN_LLVM_9 1
+# endif
+# define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE \
+ __attribute__((availability(macos, strict, introduced = 10.15))) \
+ __attribute__((availability(ios, strict, introduced = 13.0))) \
+ __attribute__((availability(tvos, strict, introduced = 13.0))) \
+ __attribute__((availability(watchos, strict, introduced = 6.0)))
+# define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_PUSH \
+ _Pragma("clang attribute push(__attribute__((availability(macos,strict,introduced=10.15))), apply_to=any(function,record))") \
+ _Pragma("clang attribute push(__attribute__((availability(ios,strict,introduced=13.0))), apply_to=any(function,record))") \
+ _Pragma("clang attribute push(__attribute__((availability(tvos,strict,introduced=13.0))), apply_to=any(function,record))") \
+ _Pragma("clang attribute push(__attribute__((availability(watchos,strict,introduced=6.0))), apply_to=any(function,record))")
+# define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_POP \
+ _Pragma("clang attribute pop") \
+ _Pragma("clang attribute pop") \
+ _Pragma("clang attribute pop") \
+ _Pragma("clang attribute pop")
+
+// LLVM 4
+# if defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 50000
+# define _LIBCPP_INTRODUCED_IN_LLVM_4 0
+# else
+# define _LIBCPP_INTRODUCED_IN_LLVM_4 1
+# endif
+# define _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE __attribute__((availability(watchos, strict, introduced = 5.0)))
+
+// clang-format on
+
+#else
+
+// ...New vendors can add availability markup here...
+
+# error \
+ "It looks like you're trying to enable vendor availability markup, but you haven't defined the corresponding macros yet!"
+
+#endif
+
+// These macros control the availability of std::bad_optional_access and
+// other exception types. These were put in the shared library to prevent
+// code bloat from every user program defining the vtable for these exception
+// types.
+//
+// Note that when exceptions are disabled, the methods that normally throw
+// these exceptions can be used even on older deployment targets, but those
+// methods will abort instead of throwing.
+#define _LIBCPP_AVAILABILITY_HAS_BAD_OPTIONAL_ACCESS _LIBCPP_INTRODUCED_IN_LLVM_4
+#define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE
+
+#define _LIBCPP_AVAILABILITY_HAS_BAD_VARIANT_ACCESS _LIBCPP_INTRODUCED_IN_LLVM_4
+#define _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE
+
+#define _LIBCPP_AVAILABILITY_HAS_BAD_ANY_CAST _LIBCPP_INTRODUCED_IN_LLVM_4
+#define _LIBCPP_AVAILABILITY_BAD_ANY_CAST _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE
+
+// These macros control the availability of all parts of <filesystem> that
+// depend on something in the dylib.
+#define _LIBCPP_AVAILABILITY_HAS_FILESYSTEM_LIBRARY _LIBCPP_INTRODUCED_IN_LLVM_9
+#define _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE
+#define _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_PUSH
+#define _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_POP
+
+// This controls the availability of the C++20 synchronization library,
+// which requires shared library support for various operations
+// (see libcxx/src/atomic.cpp). This includes <barier>, <latch>,
+// <semaphore>, and notification functions on std::atomic.
+#define _LIBCPP_AVAILABILITY_HAS_SYNC _LIBCPP_INTRODUCED_IN_LLVM_11
+#define _LIBCPP_AVAILABILITY_SYNC _LIBCPP_INTRODUCED_IN_LLVM_11_ATTRIBUTE
+
+// Enable additional explicit instantiations of iostreams components. This
+// reduces the number of weak definitions generated in programs that use
+// iostreams by providing a single strong definition in the shared library.
+//
+// TODO: Enable additional explicit instantiations on GCC once it supports exclude_from_explicit_instantiation,
+// or once libc++ doesn't use the attribute anymore.
+// TODO: Enable them on Windows once https://llvm.org/PR41018 has been fixed.
+#if !defined(_LIBCPP_COMPILER_GCC) && !defined(_WIN32)
+# define _LIBCPP_AVAILABILITY_HAS_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1 _LIBCPP_INTRODUCED_IN_LLVM_12
+#else
+# define _LIBCPP_AVAILABILITY_HAS_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1 0
+#endif
+
+// This controls the availability of floating-point std::to_chars functions.
+// These overloads were added later than the integer overloads.
+#define _LIBCPP_AVAILABILITY_HAS_TO_CHARS_FLOATING_POINT _LIBCPP_INTRODUCED_IN_LLVM_14
+#define _LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_INTRODUCED_IN_LLVM_14_ATTRIBUTE
+
+// This controls whether the library claims to provide a default verbose
+// termination function, and consequently whether the headers will try
+// to use it when the mechanism isn't overriden at compile-time.
+#define _LIBCPP_AVAILABILITY_HAS_VERBOSE_ABORT _LIBCPP_INTRODUCED_IN_LLVM_15
+#define _LIBCPP_AVAILABILITY_VERBOSE_ABORT _LIBCPP_INTRODUCED_IN_LLVM_15_ATTRIBUTE
+
+// This controls the availability of the C++17 std::pmr library,
+// which is implemented in large part in the built library.
+//
+// TODO: Enable std::pmr markup once https://github.com/llvm/llvm-project/issues/40340 has been fixed
+// Until then, it is possible for folks to try to use `std::pmr` when back-deploying to targets that don't support
+// it and it'll be a load-time error, but we don't have a good alternative because the library won't compile if we
+// use availability annotations until that bug has been fixed.
+#define _LIBCPP_AVAILABILITY_HAS_PMR _LIBCPP_INTRODUCED_IN_LLVM_16
+#define _LIBCPP_AVAILABILITY_PMR
+
+// These macros controls the availability of __cxa_init_primary_exception
+// in the built library, which std::make_exception_ptr might use
+// (see libcxx/include/__exception/exception_ptr.h).
+#define _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION _LIBCPP_INTRODUCED_IN_LLVM_18
+#define _LIBCPP_AVAILABILITY_INIT_PRIMARY_EXCEPTION _LIBCPP_INTRODUCED_IN_LLVM_18_ATTRIBUTE
+
+// This controls the availability of C++23 <print>, which
+// has a dependency on the built library (it needs access to
+// the underlying buffer types of std::cout, std::cerr, and std::clog.
+#define _LIBCPP_AVAILABILITY_HAS_PRINT _LIBCPP_INTRODUCED_IN_LLVM_18
+#define _LIBCPP_AVAILABILITY_PRINT _LIBCPP_INTRODUCED_IN_LLVM_18_ATTRIBUTE
+
+// This controls the availability of the C++20 time zone database.
+// The parser code is built in the library.
+#define _LIBCPP_AVAILABILITY_HAS_TZDB _LIBCPP_INTRODUCED_IN_LLVM_19
+#define _LIBCPP_AVAILABILITY_TZDB _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE
+
+// These macros determine whether we assume that std::bad_function_call and
+// std::bad_expected_access provide a key function in the dylib. This allows
+// centralizing their vtable and typeinfo instead of having all TUs provide
+// a weak definition that then gets deduplicated.
+#define _LIBCPP_AVAILABILITY_HAS_BAD_FUNCTION_CALL_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19
+#define _LIBCPP_AVAILABILITY_BAD_FUNCTION_CALL_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE
+#define _LIBCPP_AVAILABILITY_HAS_BAD_EXPECTED_ACCESS_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19
+#define _LIBCPP_AVAILABILITY_BAD_EXPECTED_ACCESS_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE
+
+// Define availability attributes that depend on _LIBCPP_HAS_NO_EXCEPTIONS.
+// Those are defined in terms of the availability attributes above, and
+// should not be vendor-specific.
+#if defined(_LIBCPP_HAS_NO_EXCEPTIONS)
+# define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST
+# define _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS
+# define _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS
+#else
+# define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _LIBCPP_AVAILABILITY_BAD_ANY_CAST
+# define _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS
+# define _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS
+#endif
+
+// Define availability attributes that depend on both
+// _LIBCPP_HAS_NO_EXCEPTIONS and _LIBCPP_HAS_NO_RTTI.
+#if defined(_LIBCPP_HAS_NO_EXCEPTIONS) || defined(_LIBCPP_HAS_NO_RTTI)
+# undef _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION
+# undef _LIBCPP_AVAILABILITY_INIT_PRIMARY_EXCEPTION
+# define _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION 0
+# define _LIBCPP_AVAILABILITY_INIT_PRIMARY_EXCEPTION
+#endif
+
+#endif // _LIBCPP___CONFIGURATION_AVAILABILITY_H
diff --git a/libcxx/include/__cxx03/__configuration/compiler.h b/libcxx/include/__cxx03/__configuration/compiler.h
new file mode 100644
index 00000000000000..80ece22bb50bd6
--- /dev/null
+++ b/libcxx/include/__cxx03/__configuration/compiler.h
@@ -0,0 +1,51 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONFIGURATION_COMPILER_H
+#define _LIBCPP___CONFIGURATION_COMPILER_H
+
+#include <__config_site>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+#if defined(__apple_build_version__)
+// Given AppleClang XX.Y.Z, _LIBCPP_APPLE_CLANG_VER is XXYZ (e.g. AppleClang 14.0.3 => 1403)
+# define _LIBCPP_COMPILER_CLANG_BASED
+# define _LIBCPP_APPLE_CLANG_VER (__apple_build_version__ / 10000)
+#elif defined(__clang__)
+# define _LIBCPP_COMPILER_CLANG_BASED
+# define _LIBCPP_CLANG_VER (__clang_major__ * 100 + __clang_minor__)
+#elif defined(__GNUC__)
+# define _LIBCPP_COMPILER_GCC
+# define _LIBCPP_GCC_VER (__GNUC__ * 100 + __GNUC_MINOR__)
+#endif
+
+#ifdef __cplusplus
+
+// Warn if a compiler version is used that is not supported anymore
+// LLVM RELEASE Update the minimum compiler versions
+# if defined(_LIBCPP_CLANG_VER)
+# if _LIBCPP_CLANG_VER < 1700
+# warning "Libc++ only supports Clang 17 and later"
+# endif
+# elif defined(_LIBCPP_APPLE_CLANG_VER)
+# if _LIBCPP_APPLE_CLANG_VER < 1500
+# warning "Libc++ only supports AppleClang 15 and later"
+# endif
+# elif defined(_LIBCPP_GCC_VER)
+# if _LIBCPP_GCC_VER < 1400
+# warning "Libc++ only supports GCC 14 and later"
+# endif
+# endif
+
+#endif
+
+#endif // _LIBCPP___CONFIGURATION_COMPILER_H
diff --git a/libcxx/include/__cxx03/__configuration/language.h b/libcxx/include/__cxx03/__configuration/language.h
new file mode 100644
index 00000000000000..fa62a7b6f5c2a1
--- /dev/null
+++ b/libcxx/include/__cxx03/__configuration/language.h
@@ -0,0 +1,46 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONFIGURATION_LANGUAGE_H
+#define _LIBCPP___CONFIGURATION_LANGUAGE_H
+
+#include <__config_site>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+// NOLINTBEGIN(libcpp-cpp-version-check)
+#ifdef __cplusplus
+# if __cplusplus <= 201103L
+# define _LIBCPP_STD_VER 11
+# elif __cplusplus <= 201402L
+# define _LIBCPP_STD_VER 14
+# elif __cplusplus <= 201703L
+# define _LIBCPP_STD_VER 17
+# elif __cplusplus <= 202002L
+# define _LIBCPP_STD_VER 20
+# elif __cplusplus <= 202302L
+# define _LIBCPP_STD_VER 23
+# else
+// Expected release year of the next C++ standard
+# define _LIBCPP_STD_VER 26
+# endif
+#endif // __cplusplus
+// NOLINTEND(libcpp-cpp-version-check)
+
+#if !defined(__cpp_rtti) || __cpp_rtti < 199711L
+# define _LIBCPP_HAS_NO_RTTI
+#endif
+
+#if !defined(__cpp_exceptions) || __cpp_exceptions < 199711L
+# define _LIBCPP_HAS_NO_EXCEPTIONS
+#endif
+
+#endif // _LIBCPP___CONFIGURATION_LANGUAGE_H
diff --git a/libcxx/include/__cxx03/__configuration/platform.h b/libcxx/include/__cxx03/__configuration/platform.h
new file mode 100644
index 00000000000000..27f68d04e8a8d9
--- /dev/null
+++ b/libcxx/include/__cxx03/__configuration/platform.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONFIGURATION_PLATFORM_H
+#define _LIBCPP___CONFIGURATION_PLATFORM_H
+
+#include <__config_site>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+#if defined(__ELF__)
+# define _LIBCPP_OBJECT_FORMAT_ELF 1
+#elif defined(__MACH__)
+# define _LIBCPP_OBJECT_FORMAT_MACHO 1
+#elif defined(_WIN32)
+# define _LIBCPP_OBJECT_FORMAT_COFF 1
+#elif defined(__wasm__)
+# define _LIBCPP_OBJECT_FORMAT_WASM 1
+#elif defined(_AIX)
+# define _LIBCPP_OBJECT_FORMAT_XCOFF 1
+#else
+// ... add new file formats here ...
+#endif
+
+// Need to detect which libc we're using if we're on Linux.
+#if defined(__linux__)
+# include <features.h>
+# if defined(__GLIBC_PREREQ)
+# define _LIBCPP_GLIBC_PREREQ(a, b) __GLIBC_PREREQ(a, b)
+# else
+# define _LIBCPP_GLIBC_PREREQ(a, b) 0
+# endif // defined(__GLIBC_PREREQ)
+#endif // defined(__linux__)
+
+#ifndef __BYTE_ORDER__
+# error \
+ "Your compiler doesn't seem to define __BYTE_ORDER__, which is required by libc++ to know the endianness of your target platform"
+#endif
+
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+# define _LIBCPP_LITTLE_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+# define _LIBCPP_BIG_ENDIAN
+#endif // __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+
+#endif // _LIBCPP___CONFIGURATION_PLATFORM_H
diff --git a/libcxx/include/__cxx03/__coroutine/coroutine_handle.h b/libcxx/include/__cxx03/__coroutine/coroutine_handle.h
new file mode 100644
index 00000000000000..4557a6643c2393
--- /dev/null
+++ b/libcxx/include/__cxx03/__coroutine/coroutine_handle.h
@@ -0,0 +1,176 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COROUTINE_COROUTINE_HANDLE_H
+#define _LIBCPP___COROUTINE_COROUTINE_HANDLE_H
+
+#include <__assert>
+#include <__config>
+#include <__functional/hash.h>
+#include <__memory/addressof.h>
+#include <__type_traits/remove_cv.h>
+#include <compare>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// [coroutine.handle]
+template <class _Promise = void>
+struct _LIBCPP_TEMPLATE_VIS coroutine_handle;
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS coroutine_handle<void> {
+public:
+ // [coroutine.handle.con], construct/reset
+ constexpr coroutine_handle() noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr coroutine_handle(nullptr_t) noexcept {}
+
+ _LIBCPP_HIDE_FROM_ABI coroutine_handle& operator=(nullptr_t) noexcept {
+ __handle_ = nullptr;
+ return *this;
+ }
+
+ // [coroutine.handle.export.import], export/import
+ _LIBCPP_HIDE_FROM_ABI constexpr void* address() const noexcept { return __handle_; }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr coroutine_handle from_address(void* __addr) noexcept {
+ coroutine_handle __tmp;
+ __tmp.__handle_ = __addr;
+ return __tmp;
+ }
+
+ // [coroutine.handle.observers], observers
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return __handle_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI bool done() const {
+ _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(__is_suspended(), "done() can be called only on suspended coroutines");
+ return __builtin_coro_done(__handle_);
+ }
+
+ // [coroutine.handle.resumption], resumption
+ _LIBCPP_HIDE_FROM_ABI void operator()() const { resume(); }
+
+ _LIBCPP_HIDE_FROM_ABI void resume() const {
+ _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(__is_suspended(), "resume() can be called only on suspended coroutines");
+ _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(!done(), "resume() has undefined behavior when the coroutine is done");
+ __builtin_coro_resume(__handle_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void destroy() const {
+ _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(__is_suspended(), "destroy() can be called only on suspended coroutines");
+ __builtin_coro_destroy(__handle_);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI bool __is_suspended() const {
+ // FIXME actually implement a check for if the coro is suspended.
+ return __handle_ != nullptr;
+ }
+
+ void* __handle_ = nullptr;
+};
+
+// [coroutine.handle.compare]
+inline _LIBCPP_HIDE_FROM_ABI constexpr bool operator==(coroutine_handle<> __x, coroutine_handle<> __y) noexcept {
+ return __x.address() == __y.address();
+}
+inline _LIBCPP_HIDE_FROM_ABI constexpr strong_ordering
+operator<=>(coroutine_handle<> __x, coroutine_handle<> __y) noexcept {
+ return compare_three_way()(__x.address(), __y.address());
+}
+
+template <class _Promise>
+struct _LIBCPP_TEMPLATE_VIS coroutine_handle {
+public:
+ // [coroutine.handle.con], construct/reset
+ constexpr coroutine_handle() noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr coroutine_handle(nullptr_t) noexcept {}
+
+ _LIBCPP_HIDE_FROM_ABI static coroutine_handle from_promise(_Promise& __promise) {
+ using _RawPromise = __remove_cv_t<_Promise>;
+ coroutine_handle __tmp;
+ __tmp.__handle_ =
+ __builtin_coro_promise(std::addressof(const_cast<_RawPromise&>(__promise)), alignof(_Promise), true);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI coroutine_handle& operator=(nullptr_t) noexcept {
+ __handle_ = nullptr;
+ return *this;
+ }
+
+ // [coroutine.handle.export.import], export/import
+ _LIBCPP_HIDE_FROM_ABI constexpr void* address() const noexcept { return __handle_; }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr coroutine_handle from_address(void* __addr) noexcept {
+ coroutine_handle __tmp;
+ __tmp.__handle_ = __addr;
+ return __tmp;
+ }
+
+ // [coroutine.handle.conv], conversion
+ _LIBCPP_HIDE_FROM_ABI constexpr operator coroutine_handle<>() const noexcept {
+ return coroutine_handle<>::from_address(address());
+ }
+
+ // [coroutine.handle.observers], observers
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return __handle_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI bool done() const {
+ _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(__is_suspended(), "done() can be called only on suspended coroutines");
+ return __builtin_coro_done(__handle_);
+ }
+
+ // [coroutine.handle.resumption], resumption
+ _LIBCPP_HIDE_FROM_ABI void operator()() const { resume(); }
+
+ _LIBCPP_HIDE_FROM_ABI void resume() const {
+ _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(__is_suspended(), "resume() can be called only on suspended coroutines");
+ _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(!done(), "resume() has undefined behavior when the coroutine is done");
+ __builtin_coro_resume(__handle_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void destroy() const {
+ _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(__is_suspended(), "destroy() can be called only on suspended coroutines");
+ __builtin_coro_destroy(__handle_);
+ }
+
+ // [coroutine.handle.promise], promise access
+ _LIBCPP_HIDE_FROM_ABI _Promise& promise() const {
+ return *static_cast<_Promise*>(__builtin_coro_promise(this->__handle_, alignof(_Promise), false));
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI bool __is_suspended() const {
+ // FIXME actually implement a check for if the coro is suspended.
+ return __handle_ != nullptr;
+ }
+ void* __handle_ = nullptr;
+};
+
+// [coroutine.handle.hash]
+template <class _Tp>
+struct hash<coroutine_handle<_Tp>> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const coroutine_handle<_Tp>& __v) const noexcept {
+ return hash<void*>()(__v.address());
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // __LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___COROUTINE_COROUTINE_HANDLE_H
diff --git a/libcxx/include/__cxx03/__coroutine/coroutine_traits.h b/libcxx/include/__cxx03/__coroutine/coroutine_traits.h
new file mode 100644
index 00000000000000..78f05341f7486a
--- /dev/null
+++ b/libcxx/include/__cxx03/__coroutine/coroutine_traits.h
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COROUTINE_COROUTINE_TRAITS_H
+#define _LIBCPP___COROUTINE_COROUTINE_TRAITS_H
+
+#include <__config>
+#include <__type_traits/void_t.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// [coroutine.traits]
+// [coroutine.traits.primary]
+// The header <coroutine> defined the primary template coroutine_traits such that
+// if ArgTypes is a parameter pack of types and if the qualified-id R::promise_type
+// is valid and denotes a type ([temp.deduct]), then coroutine_traits<R, ArgTypes...>
+// has the following publicly accessible memebr:
+//
+// using promise_type = typename R::promise_type;
+//
+// Otherwise, coroutine_traits<R, ArgTypes...> has no members.
+template <class _Tp, class = void>
+struct __coroutine_traits_sfinae {};
+
+template <class _Tp>
+struct __coroutine_traits_sfinae< _Tp, __void_t<typename _Tp::promise_type> > {
+ using promise_type = typename _Tp::promise_type;
+};
+
+template <class _Ret, class... _Args>
+struct coroutine_traits : public __coroutine_traits_sfinae<_Ret> {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // __LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___COROUTINE_COROUTINE_TRAITS_H
diff --git a/libcxx/include/__cxx03/__coroutine/noop_coroutine_handle.h b/libcxx/include/__cxx03/__coroutine/noop_coroutine_handle.h
new file mode 100644
index 00000000000000..da13d579604b55
--- /dev/null
+++ b/libcxx/include/__cxx03/__coroutine/noop_coroutine_handle.h
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___COROUTINE_NOOP_COROUTINE_HANDLE_H
+#define _LIBCPP___COROUTINE_NOOP_COROUTINE_HANDLE_H
+
+#include <__config>
+#include <__coroutine/coroutine_handle.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if __has_builtin(__builtin_coro_noop) || defined(_LIBCPP_COMPILER_GCC)
+
+// [coroutine.noop]
+// [coroutine.promise.noop]
+struct noop_coroutine_promise {};
+
+// [coroutine.handle.noop]
+template <>
+struct _LIBCPP_TEMPLATE_VIS coroutine_handle<noop_coroutine_promise> {
+public:
+ // [coroutine.handle.noop.conv], conversion
+ _LIBCPP_HIDE_FROM_ABI constexpr operator coroutine_handle<>() const noexcept {
+ return coroutine_handle<>::from_address(address());
+ }
+
+ // [coroutine.handle.noop.observers], observers
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI constexpr bool done() const noexcept { return false; }
+
+ // [coroutine.handle.noop.resumption], resumption
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()() const noexcept {}
+ _LIBCPP_HIDE_FROM_ABI constexpr void resume() const noexcept {}
+ _LIBCPP_HIDE_FROM_ABI constexpr void destroy() const noexcept {}
+
+ // [coroutine.handle.noop.promise], promise access
+ _LIBCPP_HIDE_FROM_ABI noop_coroutine_promise& promise() const noexcept {
+ return *static_cast<noop_coroutine_promise*>(
+ __builtin_coro_promise(this->__handle_, alignof(noop_coroutine_promise), false));
+ }
+
+ // [coroutine.handle.noop.address], address
+ _LIBCPP_HIDE_FROM_ABI constexpr void* address() const noexcept { return __handle_; }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI friend coroutine_handle<noop_coroutine_promise> noop_coroutine() noexcept;
+
+# if __has_builtin(__builtin_coro_noop)
+ _LIBCPP_HIDE_FROM_ABI coroutine_handle() noexcept { this->__handle_ = __builtin_coro_noop(); }
+
+ void* __handle_ = nullptr;
+
+# elif defined(_LIBCPP_COMPILER_GCC)
+ // GCC doesn't implement __builtin_coro_noop().
+ // Construct the coroutine frame manually instead.
+ struct __noop_coroutine_frame_ty_ {
+ static void __dummy_resume_destroy_func() {}
+
+ void (*__resume_)() = __dummy_resume_destroy_func;
+ void (*__destroy_)() = __dummy_resume_destroy_func;
+ struct noop_coroutine_promise __promise_;
+ };
+
+ static __noop_coroutine_frame_ty_ __noop_coroutine_frame_;
+
+ void* __handle_ = &__noop_coroutine_frame_;
+
+ _LIBCPP_HIDE_FROM_ABI coroutine_handle() noexcept = default;
+
+# endif // __has_builtin(__builtin_coro_noop)
+};
+
+using noop_coroutine_handle = coroutine_handle<noop_coroutine_promise>;
+
+# if defined(_LIBCPP_COMPILER_GCC)
+inline noop_coroutine_handle::__noop_coroutine_frame_ty_ noop_coroutine_handle::__noop_coroutine_frame_{};
+# endif
+
+// [coroutine.noop.coroutine]
+inline _LIBCPP_HIDE_FROM_ABI noop_coroutine_handle noop_coroutine() noexcept { return noop_coroutine_handle(); }
+
+# endif // __has_builtin(__builtin_coro_noop) || defined(_LIBCPP_COMPILER_GCC)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // __LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___COROUTINE_NOOP_COROUTINE_HANDLE_H
diff --git a/libcxx/include/__cxx03/__coroutine/trivial_awaitables.h b/libcxx/include/__cxx03/__coroutine/trivial_awaitables.h
new file mode 100644
index 00000000000000..b604bd3c2d8ad2
--- /dev/null
+++ b/libcxx/include/__cxx03/__coroutine/trivial_awaitables.h
@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __LIBCPP___COROUTINE_TRIVIAL_AWAITABLES_H
+#define __LIBCPP___COROUTINE_TRIVIAL_AWAITABLES_H
+
+#include <__config>
+#include <__coroutine/coroutine_handle.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// [coroutine.trivial.awaitables]
+struct suspend_never {
+ _LIBCPP_HIDE_FROM_ABI constexpr bool await_ready() const noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI constexpr void await_suspend(coroutine_handle<>) const noexcept {}
+ _LIBCPP_HIDE_FROM_ABI constexpr void await_resume() const noexcept {}
+};
+
+struct suspend_always {
+ _LIBCPP_HIDE_FROM_ABI constexpr bool await_ready() const noexcept { return false; }
+ _LIBCPP_HIDE_FROM_ABI constexpr void await_suspend(coroutine_handle<>) const noexcept {}
+ _LIBCPP_HIDE_FROM_ABI constexpr void await_resume() const noexcept {}
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // __LIBCPP_STD_VER >= 20
+
+#endif // __LIBCPP___COROUTINE_TRIVIAL_AWAITABLES_H
diff --git a/libcxx/include/__cxx03/__debug_utils/randomize_range.h b/libcxx/include/__cxx03/__debug_utils/randomize_range.h
new file mode 100644
index 00000000000000..7eb77d81ab2a3d
--- /dev/null
+++ b/libcxx/include/__cxx03/__debug_utils/randomize_range.h
@@ -0,0 +1,42 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LIBCXX_DEBUG_RANDOMIZE_RANGE_H
+#define _LIBCPP___LIBCXX_DEBUG_RANDOMIZE_RANGE_H
+
+#include <__config>
+
+#ifdef _LIBCPP_DEBUG_RANDOMIZE_UNSPECIFIED_STABILITY
+# include <__algorithm/shuffle.h>
+# include <__type_traits/is_constant_evaluated.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _Iterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __debug_randomize_range(_Iterator __first, _Sentinel __last) {
+#ifdef _LIBCPP_DEBUG_RANDOMIZE_UNSPECIFIED_STABILITY
+# ifdef _LIBCPP_CXX03_LANG
+# error Support for unspecified stability is only for C++11 and higher
+# endif
+
+ if (!__libcpp_is_constant_evaluated())
+ std::__shuffle<_AlgPolicy>(__first, __last, __libcpp_debug_randomizer());
+#else
+ (void)__first;
+ (void)__last;
+#endif
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___LIBCXX_DEBUG_RANDOMIZE_RANGE_H
diff --git a/libcxx/include/__cxx03/__debug_utils/sanitizers.h b/libcxx/include/__cxx03/__debug_utils/sanitizers.h
new file mode 100644
index 00000000000000..d8547e32493303
--- /dev/null
+++ b/libcxx/include/__cxx03/__debug_utils/sanitizers.h
@@ -0,0 +1,104 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LIBCXX_DEBUG_UTILS_SANITIZERS_H
+#define _LIBCPP___LIBCXX_DEBUG_UTILS_SANITIZERS_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_constant_evaluated.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_HAS_NO_ASAN
+
+extern "C" {
+_LIBCPP_EXPORTED_FROM_ABI void
+__sanitizer_annotate_contiguous_container(const void*, const void*, const void*, const void*);
+_LIBCPP_EXPORTED_FROM_ABI void __sanitizer_annotate_double_ended_contiguous_container(
+ const void*, const void*, const void*, const void*, const void*, const void*);
+_LIBCPP_EXPORTED_FROM_ABI int
+__sanitizer_verify_double_ended_contiguous_container(const void*, const void*, const void*, const void*);
+}
+
+#endif // _LIBCPP_HAS_NO_ASAN
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// ASan choices
+#ifndef _LIBCPP_HAS_NO_ASAN
+# define _LIBCPP_HAS_ASAN_CONTAINER_ANNOTATIONS_FOR_ALL_ALLOCATORS 1
+#endif
+
+#ifdef _LIBCPP_HAS_ASAN_CONTAINER_ANNOTATIONS_FOR_ALL_ALLOCATORS
+// __asan_annotate_container_with_allocator determines whether containers with custom allocators are annotated. This is
+// a public customization point to disable annotations if the custom allocator assumes that the memory isn't poisoned.
+// See the https://libcxx.llvm.org/UsingLibcxx.html#turning-off-asan-annotation-in-containers for more information.
+template <class _Alloc>
+struct __asan_annotate_container_with_allocator : true_type {};
+#endif
+
+// Annotate a double-ended contiguous range.
+// - [__first_storage, __last_storage) is the allocated memory region,
+// - [__first_old_contained, __last_old_contained) is the previously allowed (unpoisoned) range, and
+// - [__first_new_contained, __last_new_contained) is the new allowed (unpoisoned) range.
+template <class _Allocator>
+_LIBCPP_HIDE_FROM_ABI void __annotate_double_ended_contiguous_container(
+ const void* __first_storage,
+ const void* __last_storage,
+ const void* __first_old_contained,
+ const void* __last_old_contained,
+ const void* __first_new_contained,
+ const void* __last_new_contained) {
+#ifdef _LIBCPP_HAS_NO_ASAN
+ (void)__first_storage;
+ (void)__last_storage;
+ (void)__first_old_contained;
+ (void)__last_old_contained;
+ (void)__first_new_contained;
+ (void)__last_new_contained;
+#else
+ if (__asan_annotate_container_with_allocator<_Allocator>::value && __first_storage != nullptr)
+ __sanitizer_annotate_double_ended_contiguous_container(
+ __first_storage,
+ __last_storage,
+ __first_old_contained,
+ __last_old_contained,
+ __first_new_contained,
+ __last_new_contained);
+#endif
+}
+
+// Annotate a contiguous range.
+// [__first_storage, __last_storage) is the allocated memory region,
+// __old_last_contained is the previously last allowed (unpoisoned) element, and
+// __new_last_contained is the new last allowed (unpoisoned) element.
+template <class _Allocator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __annotate_contiguous_container(
+ const void* __first_storage,
+ const void* __last_storage,
+ const void* __old_last_contained,
+ const void* __new_last_contained) {
+#ifdef _LIBCPP_HAS_NO_ASAN
+ (void)__first_storage;
+ (void)__last_storage;
+ (void)__old_last_contained;
+ (void)__new_last_contained;
+#else
+ if (!__libcpp_is_constant_evaluated() && __asan_annotate_container_with_allocator<_Allocator>::value &&
+ __first_storage != nullptr)
+ __sanitizer_annotate_contiguous_container(
+ __first_storage, __last_storage, __old_last_contained, __new_last_contained);
+#endif
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___LIBCXX_DEBUG_UTILS_SANITIZERS_H
diff --git a/libcxx/include/__cxx03/__debug_utils/strict_weak_ordering_check.h b/libcxx/include/__cxx03/__debug_utils/strict_weak_ordering_check.h
new file mode 100644
index 00000000000000..3a9d887284164d
--- /dev/null
+++ b/libcxx/include/__cxx03/__debug_utils/strict_weak_ordering_check.h
@@ -0,0 +1,77 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LIBCXX_DEBUG_STRICT_WEAK_ORDERING_CHECK
+#define _LIBCPP___LIBCXX_DEBUG_STRICT_WEAK_ORDERING_CHECK
+
+#include <__config>
+
+#include <__algorithm/comp_ref_type.h>
+#include <__algorithm/is_sorted.h>
+#include <__assert>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_constant_evaluated.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RandomAccessIterator, class _Comp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__check_strict_weak_ordering_sorted(_RandomAccessIterator __first, _RandomAccessIterator __last, _Comp& __comp) {
+#if _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_DEBUG
+ using __diff_t = __iter_diff_t<_RandomAccessIterator>;
+ using _Comp_ref = __comp_ref_type<_Comp>;
+ if (!__libcpp_is_constant_evaluated()) {
+ // Check if the range is actually sorted.
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ (std::is_sorted<_RandomAccessIterator, _Comp_ref>(__first, __last, _Comp_ref(__comp))),
+ "The range is not sorted after the sort, your comparator is not a valid strict-weak ordering");
+ // Limit the number of elements we need to check.
+ __diff_t __size = __last - __first > __diff_t(100) ? __diff_t(100) : __last - __first;
+ __diff_t __p = 0;
+ while (__p < __size) {
+ __diff_t __q = __p + __diff_t(1);
+ // Find first element that is greater than *(__first+__p).
+ while (__q < __size && !__comp(*(__first + __p), *(__first + __q))) {
+ ++__q;
+ }
+ // Check that the elements from __p to __q are equal between each other.
+ for (__diff_t __b = __p; __b < __q; ++__b) {
+ for (__diff_t __a = __p; __a <= __b; ++__a) {
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ !__comp(*(__first + __a), *(__first + __b)), "Your comparator is not a valid strict-weak ordering");
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ !__comp(*(__first + __b), *(__first + __a)), "Your comparator is not a valid strict-weak ordering");
+ }
+ }
+ // Check that elements between __p and __q are less than between __q and __size.
+ for (__diff_t __a = __p; __a < __q; ++__a) {
+ for (__diff_t __b = __q; __b < __size; ++__b) {
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ __comp(*(__first + __a), *(__first + __b)), "Your comparator is not a valid strict-weak ordering");
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ !__comp(*(__first + __b), *(__first + __a)), "Your comparator is not a valid strict-weak ordering");
+ }
+ }
+ // Skip these equal elements.
+ __p = __q;
+ }
+ }
+#else
+ (void)__first;
+ (void)__last;
+ (void)__comp;
+#endif // _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_DEBUG
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___LIBCXX_DEBUG_STRICT_WEAK_ORDERING_CHECK
diff --git a/libcxx/include/__cxx03/__exception/exception.h b/libcxx/include/__cxx03/__exception/exception.h
new file mode 100644
index 00000000000000..e724e1b99bd14e
--- /dev/null
+++ b/libcxx/include/__cxx03/__exception/exception.h
@@ -0,0 +1,94 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___EXCEPTION_EXCEPTION_H
+#define _LIBCPP___EXCEPTION_EXCEPTION_H
+
+#include <__config>
+
+// <vcruntime_exception.h> defines its own std::exception and std::bad_exception types,
+// which we use in order to be ABI-compatible with other STLs on Windows.
+#if defined(_LIBCPP_ABI_VCRUNTIME)
+# include <vcruntime_exception.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+namespace std { // purposefully not using versioning namespace
+
+#if defined(_LIBCPP_ABI_VCRUNTIME) && (!defined(_HAS_EXCEPTIONS) || _HAS_EXCEPTIONS != 0)
+// The std::exception class was already included above, but we're explicit about this condition here for clarity.
+
+#elif defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
+// However, <vcruntime_exception.h> does not define std::exception and std::bad_exception
+// when _HAS_EXCEPTIONS == 0.
+//
+// Since libc++ still wants to provide the std::exception hierarchy even when _HAS_EXCEPTIONS == 0
+// (after all those are simply types like any other), we define an ABI-compatible version
+// of the VCRuntime std::exception and std::bad_exception types in that mode.
+
+struct __std_exception_data {
+ char const* _What;
+ bool _DoFree;
+};
+
+class exception { // base of all library exceptions
+public:
+ exception() _NOEXCEPT : __data_() {}
+
+ explicit exception(char const* __message) _NOEXCEPT : __data_() {
+ __data_._What = __message;
+ __data_._DoFree = true;
+ }
+
+ exception(exception const&) _NOEXCEPT {}
+
+ exception& operator=(exception const&) _NOEXCEPT { return *this; }
+
+ virtual ~exception() _NOEXCEPT {}
+
+ virtual char const* what() const _NOEXCEPT { return __data_._What ? __data_._What : "Unknown exception"; }
+
+private:
+ __std_exception_data __data_;
+};
+
+class bad_exception : public exception {
+public:
+ bad_exception() _NOEXCEPT : exception("bad exception") {}
+};
+
+#else // !defined(_LIBCPP_ABI_VCRUNTIME)
+// On all other platforms, we define our own std::exception and std::bad_exception types
+// regardless of whether exceptions are turned on as a language feature.
+
+class _LIBCPP_EXPORTED_FROM_ABI exception {
+public:
+ _LIBCPP_HIDE_FROM_ABI exception() _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI exception(const exception&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI exception& operator=(const exception&) _NOEXCEPT = default;
+
+ virtual ~exception() _NOEXCEPT;
+ virtual const char* what() const _NOEXCEPT;
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_exception : public exception {
+public:
+ _LIBCPP_HIDE_FROM_ABI bad_exception() _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI bad_exception(const bad_exception&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_exception& operator=(const bad_exception&) _NOEXCEPT = default;
+ ~bad_exception() _NOEXCEPT override;
+ const char* what() const _NOEXCEPT override;
+};
+#endif // !_LIBCPP_ABI_VCRUNTIME
+
+} // namespace std
+
+#endif // _LIBCPP___EXCEPTION_EXCEPTION_H
diff --git a/libcxx/include/__cxx03/__exception/exception_ptr.h b/libcxx/include/__cxx03/__exception/exception_ptr.h
new file mode 100644
index 00000000000000..beadd9212abd10
--- /dev/null
+++ b/libcxx/include/__cxx03/__exception/exception_ptr.h
@@ -0,0 +1,177 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___EXCEPTION_EXCEPTION_PTR_H
+#define _LIBCPP___EXCEPTION_EXCEPTION_PTR_H
+
+#include <__config>
+#include <__exception/operations.h>
+#include <__memory/addressof.h>
+#include <__memory/construct_at.h>
+#include <__type_traits/decay.h>
+#include <cstddef>
+#include <cstdlib>
+#include <new>
+#include <typeinfo>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_ABI_MICROSOFT
+
+# if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION
+
+namespace __cxxabiv1 {
+
+extern "C" {
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* __cxa_allocate_exception(size_t) throw();
+_LIBCPP_OVERRIDABLE_FUNC_VIS void __cxa_free_exception(void*) throw();
+
+struct __cxa_exception;
+_LIBCPP_OVERRIDABLE_FUNC_VIS __cxa_exception* __cxa_init_primary_exception(
+ void*,
+ std::type_info*,
+# if defined(_WIN32)
+ void(__thiscall*)(void*)) throw();
+# elif defined(__wasm__)
+ // In Wasm, a destructor returns its argument
+ void* (*)(void*)) throw();
+# else
+ void (*)(void*)) throw();
+# endif
+}
+
+} // namespace __cxxabiv1
+
+# endif
+
+#endif
+
+namespace std { // purposefully not using versioning namespace
+
+#ifndef _LIBCPP_ABI_MICROSOFT
+
+class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
+ void* __ptr_;
+
+ static exception_ptr __from_native_exception_pointer(void*) _NOEXCEPT;
+
+ template <class _Ep>
+ friend _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep) _NOEXCEPT;
+
+public:
+ // exception_ptr is basically a COW string.
+ using __trivially_relocatable = exception_ptr;
+
+ _LIBCPP_HIDE_FROM_ABI exception_ptr() _NOEXCEPT : __ptr_() {}
+ _LIBCPP_HIDE_FROM_ABI exception_ptr(nullptr_t) _NOEXCEPT : __ptr_() {}
+
+ exception_ptr(const exception_ptr&) _NOEXCEPT;
+ exception_ptr& operator=(const exception_ptr&) _NOEXCEPT;
+ ~exception_ptr() _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return __ptr_ != nullptr; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT {
+ return __x.__ptr_ == __y.__ptr_;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT {
+ return !(__x == __y);
+ }
+
+ friend _LIBCPP_EXPORTED_FROM_ABI exception_ptr current_exception() _NOEXCEPT;
+ friend _LIBCPP_EXPORTED_FROM_ABI void rethrow_exception(exception_ptr);
+};
+
+template <class _Ep>
+_LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+# if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
+ using _Ep2 = __decay_t<_Ep>;
+
+ void* __ex = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ep));
+# ifdef __wasm__
+ // In Wasm, a destructor returns its argument
+ (void)__cxxabiv1::__cxa_init_primary_exception(
+ __ex, const_cast<std::type_info*>(&typeid(_Ep)), [](void* __p) -> void* {
+# else
+ (void)__cxxabiv1::__cxa_init_primary_exception(__ex, const_cast<std::type_info*>(&typeid(_Ep)), [](void* __p) {
+# endif
+ std::__destroy_at(static_cast<_Ep2*>(__p));
+# ifdef __wasm__
+ return __p;
+# endif
+ });
+
+ try {
+ ::new (__ex) _Ep2(__e);
+ return exception_ptr::__from_native_exception_pointer(__ex);
+ } catch (...) {
+ __cxxabiv1::__cxa_free_exception(__ex);
+ return current_exception();
+ }
+# else
+ try {
+ throw __e;
+ } catch (...) {
+ return current_exception();
+ }
+# endif
+# else
+ ((void)__e);
+ std::abort();
+# endif
+}
+
+#else // _LIBCPP_ABI_MICROSOFT
+
+class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
+ _LIBCPP_DIAGNOSTIC_PUSH
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wunused-private-field")
+ void* __ptr1_;
+ void* __ptr2_;
+ _LIBCPP_DIAGNOSTIC_POP
+
+public:
+ exception_ptr() _NOEXCEPT;
+ exception_ptr(nullptr_t) _NOEXCEPT;
+ exception_ptr(const exception_ptr& __other) _NOEXCEPT;
+ exception_ptr& operator=(const exception_ptr& __other) _NOEXCEPT;
+ exception_ptr& operator=(nullptr_t) _NOEXCEPT;
+ ~exception_ptr() _NOEXCEPT;
+ explicit operator bool() const _NOEXCEPT;
+};
+
+_LIBCPP_EXPORTED_FROM_ABI bool operator==(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT;
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT {
+ return !(__x == __y);
+}
+
+_LIBCPP_EXPORTED_FROM_ABI void swap(exception_ptr&, exception_ptr&) _NOEXCEPT;
+
+_LIBCPP_EXPORTED_FROM_ABI exception_ptr __copy_exception_ptr(void* __except, const void* __ptr);
+_LIBCPP_EXPORTED_FROM_ABI exception_ptr current_exception() _NOEXCEPT;
+_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void rethrow_exception(exception_ptr);
+
+// This is a built-in template function which automagically extracts the required
+// information.
+template <class _E>
+void* __GetExceptionInfo(_E);
+
+template <class _Ep>
+_LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
+ return __copy_exception_ptr(std::addressof(__e), __GetExceptionInfo(__e));
+}
+
+#endif // _LIBCPP_ABI_MICROSOFT
+} // namespace std
+
+#endif // _LIBCPP___EXCEPTION_EXCEPTION_PTR_H
diff --git a/libcxx/include/__cxx03/__exception/nested_exception.h b/libcxx/include/__cxx03/__exception/nested_exception.h
new file mode 100644
index 00000000000000..feb489f87f62f5
--- /dev/null
+++ b/libcxx/include/__cxx03/__exception/nested_exception.h
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___EXCEPTION_NESTED_EXCEPTION_H
+#define _LIBCPP___EXCEPTION_NESTED_EXCEPTION_H
+
+#include <__config>
+#include <__exception/exception_ptr.h>
+#include <__memory/addressof.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_base_of.h>
+#include <__type_traits/is_class.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_final.h>
+#include <__type_traits/is_polymorphic.h>
+#include <__utility/forward.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+namespace std { // purposefully not using versioning namespace
+
+class _LIBCPP_EXPORTED_FROM_ABI nested_exception {
+ exception_ptr __ptr_;
+
+public:
+ nested_exception() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI nested_exception(const nested_exception&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI nested_exception& operator=(const nested_exception&) _NOEXCEPT = default;
+ virtual ~nested_exception() _NOEXCEPT;
+
+ // access functions
+ _LIBCPP_NORETURN void rethrow_nested() const;
+ _LIBCPP_HIDE_FROM_ABI exception_ptr nested_ptr() const _NOEXCEPT { return __ptr_; }
+};
+
+template <class _Tp>
+struct __nested : public _Tp, public nested_exception {
+ _LIBCPP_HIDE_FROM_ABI explicit __nested(const _Tp& __t) : _Tp(__t) {}
+};
+
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+template <class _Tp, class _Up, bool>
+struct __throw_with_nested;
+
+template <class _Tp, class _Up>
+struct __throw_with_nested<_Tp, _Up, true> {
+ _LIBCPP_NORETURN static inline _LIBCPP_HIDE_FROM_ABI void __do_throw(_Tp&& __t) {
+ throw __nested<_Up>(std::forward<_Tp>(__t));
+ }
+};
+
+template <class _Tp, class _Up>
+struct __throw_with_nested<_Tp, _Up, false> {
+ _LIBCPP_NORETURN static inline _LIBCPP_HIDE_FROM_ABI void __do_throw(_Tp&& __t) { throw std::forward<_Tp>(__t); }
+};
+#endif
+
+template <class _Tp>
+_LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI void throw_with_nested(_Tp&& __t) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ using _Up = __decay_t<_Tp>;
+ static_assert(is_copy_constructible<_Up>::value, "type thrown must be CopyConstructible");
+ __throw_with_nested<_Tp,
+ _Up,
+ is_class<_Up>::value && !is_base_of<nested_exception, _Up>::value &&
+ !__libcpp_is_final<_Up>::value>::__do_throw(std::forward<_Tp>(__t));
+#else
+ ((void)__t);
+ // FIXME: Make this abort
+#endif
+}
+
+template <class _From, class _To>
+struct __can_dynamic_cast
+ : _BoolConstant< is_polymorphic<_From>::value &&
+ (!is_base_of<_To, _From>::value || is_convertible<const _From*, const _To*>::value)> {};
+
+template <class _Ep, __enable_if_t< __can_dynamic_cast<_Ep, nested_exception>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void rethrow_if_nested(const _Ep& __e) {
+ const nested_exception* __nep = dynamic_cast<const nested_exception*>(std::addressof(__e));
+ if (__nep)
+ __nep->rethrow_nested();
+}
+
+template <class _Ep, __enable_if_t<!__can_dynamic_cast<_Ep, nested_exception>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void rethrow_if_nested(const _Ep&) {}
+
+} // namespace std
+
+#endif // _LIBCPP___EXCEPTION_NESTED_EXCEPTION_H
diff --git a/libcxx/include/__cxx03/__exception/operations.h b/libcxx/include/__cxx03/__exception/operations.h
new file mode 100644
index 00000000000000..0a9c7a7c7f0d88
--- /dev/null
+++ b/libcxx/include/__cxx03/__exception/operations.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___EXCEPTION_OPERATIONS_H
+#define _LIBCPP___EXCEPTION_OPERATIONS_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+namespace std { // purposefully not using versioning namespace
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS) || \
+ defined(_LIBCPP_BUILDING_LIBRARY)
+using unexpected_handler = void (*)();
+_LIBCPP_EXPORTED_FROM_ABI unexpected_handler set_unexpected(unexpected_handler) _NOEXCEPT;
+_LIBCPP_EXPORTED_FROM_ABI unexpected_handler get_unexpected() _NOEXCEPT;
+_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void unexpected();
+#endif
+
+using terminate_handler = void (*)();
+_LIBCPP_EXPORTED_FROM_ABI terminate_handler set_terminate(terminate_handler) _NOEXCEPT;
+_LIBCPP_EXPORTED_FROM_ABI terminate_handler get_terminate() _NOEXCEPT;
+
+_LIBCPP_EXPORTED_FROM_ABI bool uncaught_exception() _NOEXCEPT;
+_LIBCPP_EXPORTED_FROM_ABI int uncaught_exceptions() _NOEXCEPT;
+
+class _LIBCPP_EXPORTED_FROM_ABI exception_ptr;
+
+_LIBCPP_EXPORTED_FROM_ABI exception_ptr current_exception() _NOEXCEPT;
+_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void rethrow_exception(exception_ptr);
+} // namespace std
+
+#endif // _LIBCPP___EXCEPTION_OPERATIONS_H
diff --git a/libcxx/include/__cxx03/__exception/terminate.h b/libcxx/include/__cxx03/__exception/terminate.h
new file mode 100644
index 00000000000000..e672471dc52631
--- /dev/null
+++ b/libcxx/include/__cxx03/__exception/terminate.h
@@ -0,0 +1,22 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___EXCEPTION_TERMINATE_H
+#define _LIBCPP___EXCEPTION_TERMINATE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+namespace std { // purposefully not using versioning namespace
+_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void terminate() _NOEXCEPT;
+} // namespace std
+
+#endif // _LIBCPP___EXCEPTION_TERMINATE_H
diff --git a/libcxx/include/__cxx03/__expected/bad_expected_access.h b/libcxx/include/__cxx03/__expected/bad_expected_access.h
new file mode 100644
index 00000000000000..1b734389e8311f
--- /dev/null
+++ b/libcxx/include/__cxx03/__expected/bad_expected_access.h
@@ -0,0 +1,73 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef _LIBCPP___EXPECTED_BAD_EXPECTED_ACCESS_H
+#define _LIBCPP___EXPECTED_BAD_EXPECTED_ACCESS_H
+
+#include <__config>
+#include <__exception/exception.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Err>
+class bad_expected_access;
+
+_LIBCPP_DIAGNOSTIC_PUSH
+# if !_LIBCPP_AVAILABILITY_HAS_BAD_EXPECTED_ACCESS_KEY_FUNCTION
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wweak-vtables")
+# endif
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI bad_expected_access<void> : public exception {
+protected:
+ _LIBCPP_HIDE_FROM_ABI bad_expected_access() noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI bad_expected_access(const bad_expected_access&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI bad_expected_access(bad_expected_access&&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI bad_expected_access& operator=(const bad_expected_access&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI bad_expected_access& operator=(bad_expected_access&&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~bad_expected_access() override = default;
+
+public:
+# if _LIBCPP_AVAILABILITY_HAS_BAD_EXPECTED_ACCESS_KEY_FUNCTION
+ const char* what() const noexcept override;
+# else
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const char* what() const noexcept override { return "bad access to std::expected"; }
+# endif
+};
+_LIBCPP_DIAGNOSTIC_POP
+
+template <class _Err>
+class bad_expected_access : public bad_expected_access<void> {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit bad_expected_access(_Err __e) : __unex_(std::move(__e)) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Err& error() & noexcept { return __unex_; }
+ _LIBCPP_HIDE_FROM_ABI const _Err& error() const& noexcept { return __unex_; }
+ _LIBCPP_HIDE_FROM_ABI _Err&& error() && noexcept { return std::move(__unex_); }
+ _LIBCPP_HIDE_FROM_ABI const _Err&& error() const&& noexcept { return std::move(__unex_); }
+
+private:
+ _Err __unex_;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___EXPECTED_BAD_EXPECTED_ACCESS_H
diff --git a/libcxx/include/__cxx03/__expected/expected.h b/libcxx/include/__cxx03/__expected/expected.h
new file mode 100644
index 00000000000000..f618b20603e609
--- /dev/null
+++ b/libcxx/include/__cxx03/__expected/expected.h
@@ -0,0 +1,1875 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef _LIBCPP___EXPECTED_EXPECTED_H
+#define _LIBCPP___EXPECTED_EXPECTED_H
+
+#include <__assert>
+#include <__config>
+#include <__expected/bad_expected_access.h>
+#include <__expected/unexpect.h>
+#include <__expected/unexpected.h>
+#include <__functional/invoke.h>
+#include <__memory/addressof.h>
+#include <__memory/construct_at.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/disjunction.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/is_trivially_constructible.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/lazy.h>
+#include <__type_traits/negation.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/as_const.h>
+#include <__utility/exception_guard.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <__verbose_abort>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Err>
+class expected;
+
+template <class _Tp>
+struct __is_std_expected : false_type {};
+
+template <class _Tp, class _Err>
+struct __is_std_expected<expected<_Tp, _Err>> : true_type {};
+
+struct __expected_construct_in_place_from_invoke_tag {};
+struct __expected_construct_unexpected_from_invoke_tag {};
+
+template <class _Err, class _Arg>
+_LIBCPP_HIDE_FROM_ABI void __throw_bad_expected_access(_Arg&& __arg) {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw bad_expected_access<_Err>(std::forward<_Arg>(__arg));
+# else
+ (void)__arg;
+ _LIBCPP_VERBOSE_ABORT("bad_expected_access was thrown in -fno-exceptions mode");
+# endif
+}
+
+// If parameter type `_Tp` of `__conditional_no_unique_address` is neither
+// copyable nor movable, a constructor with this tag is provided. For that
+// constructor, the user has to provide a function and arguments. The function
+// must return an object of type `_Tp`. When the function is invoked by the
+// constructor, guaranteed copy elision kicks in and the `_Tp` is constructed
+// in place.
+struct __conditional_no_unique_address_invoke_tag {};
+
+// This class implements an object with `[[no_unique_address]]` conditionally applied to it,
+// based on the value of `_NoUnique`.
+//
+// A member of this class must always have `[[no_unique_address]]` applied to
+// it. Otherwise, the `[[no_unique_address]]` in the "`_NoUnique == true`" case
+// would not have any effect. In the `false` case, the `__v` is not
+// `[[no_unique_address]]`, so nullifies the effects of the "outer"
+// `[[no_unique_address]]` regarding data layout.
+//
+// If we had a language feature, this class would basically be replaced by `[[no_unique_address(condition)]]`.
+template <bool _NoUnique, class _Tp>
+struct __conditional_no_unique_address;
+
+template <class _Tp>
+struct __conditional_no_unique_address<true, _Tp> {
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __conditional_no_unique_address(in_place_t, _Args&&... __args)
+ : __v(std::forward<_Args>(__args)...) {}
+
+ template <class _Func, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __conditional_no_unique_address(
+ __conditional_no_unique_address_invoke_tag, _Func&& __f, _Args&&... __args)
+ : __v(std::invoke(std::forward<_Func>(__f), std::forward<_Args>(__args)...)) {}
+
+ _LIBCPP_NO_UNIQUE_ADDRESS _Tp __v;
+};
+
+template <class _Tp>
+struct __conditional_no_unique_address<false, _Tp> {
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __conditional_no_unique_address(in_place_t, _Args&&... __args)
+ : __v(std::forward<_Args>(__args)...) {}
+
+ template <class _Func, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __conditional_no_unique_address(
+ __conditional_no_unique_address_invoke_tag, _Func&& __f, _Args&&... __args)
+ : __v(std::invoke(std::forward<_Func>(__f), std::forward<_Args>(__args)...)) {}
+
+ _Tp __v;
+};
+
+// This function returns whether the type `_Second` can be stuffed into the tail padding
+// of the `_First` type if both of them are given `[[no_unique_address]]`.
+template <class _First, class _Second>
+inline constexpr bool __fits_in_tail_padding = []() {
+ struct __x {
+ _LIBCPP_NO_UNIQUE_ADDRESS _First __first;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Second __second;
+ };
+ return sizeof(__x) == sizeof(_First);
+}();
+
+// This class implements the storage used by `std::expected`. We have a few
+// goals for this storage:
+// 1. Whenever the underlying {_Tp | _Unex} combination has free bytes in its
+// tail padding, we should reuse it to store the bool discriminator of the
+// expected, so as to save space.
+// 2. Whenever the `expected<_Tp, _Unex>` as a whole has free bytes in its tail
+// padding, we should allow an object following the expected to be stored in
+// its tail padding.
+// 3. However, we never want a user object (say `X`) that would follow an
+// `expected<_Tp, _Unex>` to be stored in the padding bytes of the
+// underlying {_Tp | _Unex} union, if any. That is because we use
+// `construct_at` on that union, which would end up overwriting the `X`
+// member if it is stored in the tail padding of the union.
+//
+// To achieve this, `__expected_base`'s logic is implemented in an inner
+// `__repr` class. `__expected_base` holds one `__repr` member which is
+// conditionally `[[no_unique_address]]`. The `__repr` class holds the
+// underlying {_Tp | _Unex} union and a boolean "has value" flag.
+//
+// Which one of the `__repr_`/`__union_` members is `[[no_unique_address]]`
+// depends on whether the "has value" boolean fits into the tail padding of
+// the underlying {_Tp | _Unex} union:
+//
+// - In case the "has value" bool fits into the tail padding of the union, the
+// whole `__repr_` member is _not_ `[[no_unique_address]]` as it needs to be
+// transparently replaced on `emplace()`/`swap()` etc.
+// - In case the "has value" bool does not fit into the tail padding of the
+// union, only the union member must be transparently replaced (therefore is
+// _not_ `[[no_unique_address]]`) and the "has value" flag must be adjusted
+// manually.
+//
+// This way, the member that is transparently replaced on mutating operations
+// is never `[[no_unique_address]]`, satisfying the requirements from
+// "[basic.life]" in the standard.
+//
+// Stripped away of all superfluous elements, the layout of `__expected_base`
+// then looks like this:
+//
+// template <class Tp, class Err>
+// class expected_base {
+// union union_t {
+// [[no_unique_address]] Tp val;
+// [[no_unique_address]] Err unex;
+// };
+//
+// static constexpr bool put_flag_in_tail = fits_in_tail_padding<union_t, bool>;
+// static constexpr bool allow_reusing_expected_tail_padding = !put_flag_in_tail;
+//
+// struct repr {
+// private:
+// // If "has value" fits into the tail, this should be
+// // `[[no_unique_address]]`, otherwise not.
+// [[no_unique_address]] conditional_no_unique_address<
+// put_flag_in_tail,
+// union_t>::type union_;
+// [[no_unique_address]] bool has_val_;
+// };
+//
+// protected:
+// // If "has value" fits into the tail, this must _not_ be
+// // `[[no_unique_address]]` so that we fill out the
+// // complete `expected` object.
+// [[no_unique_address]] conditional_no_unique_address<
+// allow_reusing_expected_tail_padding,
+// repr>::type repr_;
+// };
+//
+template <class _Tp, class _Err>
+class __expected_base {
+ // use named union because [[no_unique_address]] cannot be applied to an unnamed union,
+ // also guaranteed elision into a potentially-overlapping subobject is unsettled (and
+ // it's not clear that it's implementable, given that the function is allowed to clobber
+ // the tail padding) - see https://github.com/itanium-cxx-abi/cxx-abi/issues/107.
+ union __union_t {
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t(const __union_t&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t(const __union_t&)
+ requires(is_copy_constructible_v<_Tp> && is_copy_constructible_v<_Err> &&
+ is_trivially_copy_constructible_v<_Tp> && is_trivially_copy_constructible_v<_Err>)
+ = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t(__union_t&&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t(__union_t&&)
+ requires(is_move_constructible_v<_Tp> && is_move_constructible_v<_Err> &&
+ is_trivially_move_constructible_v<_Tp> && is_trivially_move_constructible_v<_Err>)
+ = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t& operator=(const __union_t&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t& operator=(__union_t&&) = delete;
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __union_t(in_place_t, _Args&&... __args)
+ : __val_(std::forward<_Args>(__args)...) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __union_t(unexpect_t, _Args&&... __args)
+ : __unex_(std::forward<_Args>(__args)...) {}
+
+ template <class _Func, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __union_t(
+ std::__expected_construct_in_place_from_invoke_tag, _Func&& __f, _Args&&... __args)
+ : __val_(std::invoke(std::forward<_Func>(__f), std::forward<_Args>(__args)...)) {}
+
+ template <class _Func, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __union_t(
+ std::__expected_construct_unexpected_from_invoke_tag, _Func&& __f, _Args&&... __args)
+ : __unex_(std::invoke(std::forward<_Func>(__f), std::forward<_Args>(__args)...)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr ~__union_t()
+ requires(is_trivially_destructible_v<_Tp> && is_trivially_destructible_v<_Err>)
+ = default;
+
+ // __repr's destructor handles this
+ _LIBCPP_HIDE_FROM_ABI constexpr ~__union_t() {}
+
+ _LIBCPP_NO_UNIQUE_ADDRESS _Tp __val_;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Err __unex_;
+ };
+
+ static constexpr bool __put_flag_in_tail = __fits_in_tail_padding<__union_t, bool>;
+ static constexpr bool __allow_reusing_expected_tail_padding = !__put_flag_in_tail;
+
+ struct __repr {
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr() = delete;
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(in_place_t __tag, _Args&&... __args)
+ : __union_(in_place, __tag, std::forward<_Args>(__args)...), __has_val_(true) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(unexpect_t __tag, _Args&&... __args)
+ : __union_(in_place, __tag, std::forward<_Args>(__args)...), __has_val_(false) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(std::__expected_construct_in_place_from_invoke_tag __tag,
+ _Args&&... __args)
+ : __union_(in_place, __tag, std::forward<_Args>(__args)...), __has_val_(true) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(std::__expected_construct_unexpected_from_invoke_tag __tag,
+ _Args&&... __args)
+ : __union_(in_place, __tag, std::forward<_Args>(__args)...), __has_val_(false) {}
+
+ // The return value of `__make_union` must be constructed in place in the
+ // `__v` member of `__union_`, relying on guaranteed copy elision. To do
+ // this, the `__conditional_no_unique_address_invoke_tag` constructor is
+ // called with a lambda that is immediately called inside
+ // `__conditional_no_unique_address`'s constructor.
+ template <class _OtherUnion>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(bool __has_val, _OtherUnion&& __other)
+ requires(__allow_reusing_expected_tail_padding)
+ : __union_(__conditional_no_unique_address_invoke_tag{},
+ [&] { return __make_union(__has_val, std::forward<_OtherUnion>(__other)); }),
+ __has_val_(__has_val) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr(const __repr&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr(const __repr&)
+ requires(is_copy_constructible_v<_Tp> && is_copy_constructible_v<_Err> &&
+ is_trivially_copy_constructible_v<_Tp> && is_trivially_copy_constructible_v<_Err>)
+ = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr(__repr&&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr(__repr&&)
+ requires(is_move_constructible_v<_Tp> && is_move_constructible_v<_Err> &&
+ is_trivially_move_constructible_v<_Tp> && is_trivially_move_constructible_v<_Err>)
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr& operator=(const __repr&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr& operator=(__repr&&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr ~__repr()
+ requires(is_trivially_destructible_v<_Tp> && is_trivially_destructible_v<_Err>)
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr ~__repr()
+ requires(!is_trivially_destructible_v<_Tp> || !is_trivially_destructible_v<_Err>)
+ {
+ __destroy_union_member();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __destroy_union()
+ requires(__allow_reusing_expected_tail_padding &&
+ (is_trivially_destructible_v<_Tp> && is_trivially_destructible_v<_Err>))
+ {
+ // Note: Since the destructor of the union is trivial, this does nothing
+ // except to end the lifetime of the union.
+ std::destroy_at(&__union_.__v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __destroy_union()
+ requires(__allow_reusing_expected_tail_padding &&
+ (!is_trivially_destructible_v<_Tp> || !is_trivially_destructible_v<_Err>))
+ {
+ __destroy_union_member();
+ std::destroy_at(&__union_.__v);
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __construct_union(in_place_t, _Args&&... __args)
+ requires(__allow_reusing_expected_tail_padding)
+ {
+ std::construct_at(&__union_.__v, in_place, std::forward<_Args>(__args)...);
+ __has_val_ = true;
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __construct_union(unexpect_t, _Args&&... __args)
+ requires(__allow_reusing_expected_tail_padding)
+ {
+ std::construct_at(&__union_.__v, unexpect, std::forward<_Args>(__args)...);
+ __has_val_ = false;
+ }
+
+ private:
+ template <class, class>
+ friend class __expected_base;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __destroy_union_member()
+ requires(!is_trivially_destructible_v<_Tp> || !is_trivially_destructible_v<_Err>)
+ {
+ if (__has_val_) {
+ std::destroy_at(std::addressof(__union_.__v.__val_));
+ } else {
+ std::destroy_at(std::addressof(__union_.__v.__unex_));
+ }
+ }
+
+ template <class _OtherUnion>
+ _LIBCPP_HIDE_FROM_ABI static constexpr __union_t __make_union(bool __has_val, _OtherUnion&& __other)
+ requires(__allow_reusing_expected_tail_padding)
+ {
+ if (__has_val)
+ return __union_t(in_place, std::forward<_OtherUnion>(__other).__val_);
+ else
+ return __union_t(unexpect, std::forward<_OtherUnion>(__other).__unex_);
+ }
+
+ _LIBCPP_NO_UNIQUE_ADDRESS __conditional_no_unique_address<__put_flag_in_tail, __union_t> __union_;
+ _LIBCPP_NO_UNIQUE_ADDRESS bool __has_val_;
+ };
+
+ template <class _OtherUnion>
+ _LIBCPP_HIDE_FROM_ABI static constexpr __repr __make_repr(bool __has_val, _OtherUnion&& __other)
+ requires(__put_flag_in_tail)
+ {
+ if (__has_val)
+ return __repr(in_place, std::forward<_OtherUnion>(__other).__val_);
+ else
+ return __repr(unexpect, std::forward<_OtherUnion>(__other).__unex_);
+ }
+
+protected:
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __expected_base(_Args&&... __args)
+ : __repr_(in_place, std::forward<_Args>(__args)...) {}
+
+ // In case we copy/move construct from another `expected` we need to create
+ // our `expected` so that it either has a value or not, depending on the "has
+ // value" flag of the other `expected`. To do this without falling back on
+ // `std::construct_at` we rely on guaranteed copy elision using two helper
+ // functions `__make_repr` and `__make_union`. There have to be two since
+ // there are two data layouts with different members being
+ // `[[no_unique_address]]`. GCC (as of version 13) does not do guaranteed
+ // copy elision when initializing `[[no_unique_address]]` members. The two
+ // cases are:
+ //
+ // - `__make_repr`: This is used when the "has value" flag lives in the tail
+ // of the union. In this case, the `__repr` member is _not_
+ // `[[no_unique_address]]`.
+ // - `__make_union`: When the "has value" flag does _not_ fit in the tail of
+ // the union, the `__repr` member is `[[no_unique_address]]` and the union
+ // is not.
+ //
+ // This constructor "catches" the first case and leaves the second case to
+ // `__union_t`, its constructors and `__make_union`.
+ template <class _OtherUnion>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __expected_base(bool __has_val, _OtherUnion&& __other)
+ requires(__put_flag_in_tail)
+ : __repr_(__conditional_no_unique_address_invoke_tag{},
+ [&] { return __make_repr(__has_val, std::forward<_OtherUnion>(__other)); }) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __destroy() {
+ if constexpr (__put_flag_in_tail)
+ std::destroy_at(&__repr_.__v);
+ else
+ __repr_.__v.__destroy_union();
+ }
+
+ template <class _Tag, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __construct(_Tag __tag, _Args&&... __args) {
+ if constexpr (__put_flag_in_tail)
+ std::construct_at(&__repr_.__v, __tag, std::forward<_Args>(__args)...);
+ else
+ __repr_.__v.__construct_union(__tag, std::forward<_Args>(__args)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __has_val() const { return __repr_.__v.__has_val_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t& __union() { return __repr_.__v.__union_.__v; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const __union_t& __union() const { return __repr_.__v.__union_.__v; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& __val() { return __repr_.__v.__union_.__v.__val_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& __val() const { return __repr_.__v.__union_.__v.__val_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err& __unex() { return __repr_.__v.__union_.__v.__unex_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Err& __unex() const { return __repr_.__v.__union_.__v.__unex_; }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS __conditional_no_unique_address<__allow_reusing_expected_tail_padding, __repr> __repr_;
+};
+
+template <class _Tp, class _Err>
+class expected : private __expected_base<_Tp, _Err> {
+ static_assert(!is_reference_v<_Tp> && !is_function_v<_Tp> && !is_same_v<remove_cv_t<_Tp>, in_place_t> &&
+ !is_same_v<remove_cv_t<_Tp>, unexpect_t> && !__is_std_unexpected<remove_cv_t<_Tp>>::value &&
+ __valid_std_unexpected<_Err>::value,
+ "[expected.object.general] A program that instantiates the definition of template expected<T, E> for a "
+ "reference type, a function type, or for possibly cv-qualified types in_place_t, unexpect_t, or a "
+ "specialization of unexpected for the T parameter is ill-formed. A program that instantiates the "
+ "definition of the template expected<T, E> with a type for the E parameter that is not a valid "
+ "template argument for unexpected is ill-formed.");
+
+ template <class _Up, class _OtherErr>
+ friend class expected;
+
+ using __base = __expected_base<_Tp, _Err>;
+
+public:
+ using value_type = _Tp;
+ using error_type = _Err;
+ using unexpected_type = unexpected<_Err>;
+
+ using __trivially_relocatable =
+ __conditional_t<__libcpp_is_trivially_relocatable<_Tp>::value && __libcpp_is_trivially_relocatable<_Err>::value,
+ expected,
+ void>;
+
+ template <class _Up>
+ using rebind = expected<_Up, error_type>;
+
+ // [expected.object.ctor], constructors
+ _LIBCPP_HIDE_FROM_ABI constexpr expected() noexcept(is_nothrow_default_constructible_v<_Tp>) // strengthened
+ requires is_default_constructible_v<_Tp>
+ : __base(in_place) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(const expected&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(const expected&)
+ requires(is_copy_constructible_v<_Tp> && is_copy_constructible_v<_Err> && is_trivially_copy_constructible_v<_Tp> &&
+ is_trivially_copy_constructible_v<_Err>)
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(const expected& __other) noexcept(
+ is_nothrow_copy_constructible_v<_Tp> && is_nothrow_copy_constructible_v<_Err>) // strengthened
+ requires(is_copy_constructible_v<_Tp> && is_copy_constructible_v<_Err> &&
+ !(is_trivially_copy_constructible_v<_Tp> && is_trivially_copy_constructible_v<_Err>))
+ : __base(__other.__has_val(), __other.__union()) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(expected&&)
+ requires(is_move_constructible_v<_Tp> && is_move_constructible_v<_Err> && is_trivially_move_constructible_v<_Tp> &&
+ is_trivially_move_constructible_v<_Err>)
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(expected&& __other) noexcept(
+ is_nothrow_move_constructible_v<_Tp> && is_nothrow_move_constructible_v<_Err>)
+ requires(is_move_constructible_v<_Tp> && is_move_constructible_v<_Err> &&
+ !(is_trivially_move_constructible_v<_Tp> && is_trivially_move_constructible_v<_Err>))
+ : __base(__other.__has_val(), std::move(__other.__union())) {}
+
+private:
+ template <class _Up, class _OtherErr, class _UfQual, class _OtherErrQual>
+ using __can_convert =
+ _And< is_constructible<_Tp, _UfQual>,
+ is_constructible<_Err, _OtherErrQual>,
+ _If<_Not<is_same<remove_cv_t<_Tp>, bool>>::value,
+ _And<
+ _Not<_And<is_same<_Tp, _Up>, is_same<_Err, _OtherErr>>>, // use the copy constructor instead, see #92676
+ _Not<is_constructible<_Tp, expected<_Up, _OtherErr>&>>,
+ _Not<is_constructible<_Tp, expected<_Up, _OtherErr>>>,
+ _Not<is_constructible<_Tp, const expected<_Up, _OtherErr>&>>,
+ _Not<is_constructible<_Tp, const expected<_Up, _OtherErr>>>,
+ _Not<is_convertible<expected<_Up, _OtherErr>&, _Tp>>,
+ _Not<is_convertible<expected<_Up, _OtherErr>&&, _Tp>>,
+ _Not<is_convertible<const expected<_Up, _OtherErr>&, _Tp>>,
+ _Not<is_convertible<const expected<_Up, _OtherErr>&&, _Tp>>>,
+ true_type>,
+ _Not<is_constructible<unexpected<_Err>, expected<_Up, _OtherErr>&>>,
+ _Not<is_constructible<unexpected<_Err>, expected<_Up, _OtherErr>>>,
+ _Not<is_constructible<unexpected<_Err>, const expected<_Up, _OtherErr>&>>,
+ _Not<is_constructible<unexpected<_Err>, const expected<_Up, _OtherErr>>> >;
+
+ template <class _Func, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(
+ std::__expected_construct_in_place_from_invoke_tag __tag, _Func&& __f, _Args&&... __args)
+ : __base(__tag, std::forward<_Func>(__f), std::forward<_Args>(__args)...) {}
+
+ template <class _Func, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(
+ std::__expected_construct_unexpected_from_invoke_tag __tag, _Func&& __f, _Args&&... __args)
+ : __base(__tag, std::forward<_Func>(__f), std::forward<_Args>(__args)...) {}
+
+public:
+ template <class _Up, class _OtherErr>
+ requires __can_convert<_Up, _OtherErr, const _Up&, const _OtherErr&>::value
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<const _Up&, _Tp> ||
+ !is_convertible_v<const _OtherErr&, _Err>)
+ expected(const expected<_Up, _OtherErr>& __other) noexcept(
+ is_nothrow_constructible_v<_Tp, const _Up&> &&
+ is_nothrow_constructible_v<_Err, const _OtherErr&>) // strengthened
+ : __base(__other.__has_val(), __other.__union()) {}
+
+ template <class _Up, class _OtherErr>
+ requires __can_convert<_Up, _OtherErr, _Up, _OtherErr>::value
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_Up, _Tp> || !is_convertible_v<_OtherErr, _Err>)
+ expected(expected<_Up, _OtherErr>&& __other) noexcept(
+ is_nothrow_constructible_v<_Tp, _Up> && is_nothrow_constructible_v<_Err, _OtherErr>) // strengthened
+ : __base(__other.__has_val(), std::move(__other.__union())) {}
+
+ template <class _Up = _Tp>
+ requires(!is_same_v<remove_cvref_t<_Up>, in_place_t> && !is_same_v<expected, remove_cvref_t<_Up>> &&
+ is_constructible_v<_Tp, _Up> && !__is_std_unexpected<remove_cvref_t<_Up>>::value &&
+ (!is_same_v<remove_cv_t<_Tp>, bool> || !__is_std_expected<remove_cvref_t<_Up>>::value))
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_Up, _Tp>)
+ expected(_Up&& __u) noexcept(is_nothrow_constructible_v<_Tp, _Up>) // strengthened
+ : __base(in_place, std::forward<_Up>(__u)) {}
+
+ template <class _OtherErr>
+ requires is_constructible_v<_Err, const _OtherErr&>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<const _OtherErr&, _Err>) expected(
+ const unexpected<_OtherErr>& __unex) noexcept(is_nothrow_constructible_v<_Err, const _OtherErr&>) // strengthened
+ : __base(unexpect, __unex.error()) {}
+
+ template <class _OtherErr>
+ requires is_constructible_v<_Err, _OtherErr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_OtherErr, _Err>)
+ expected(unexpected<_OtherErr>&& __unex) noexcept(is_nothrow_constructible_v<_Err, _OtherErr>) // strengthened
+ : __base(unexpect, std::move(__unex.error())) {}
+
+ template <class... _Args>
+ requires is_constructible_v<_Tp, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(in_place_t, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Tp, _Args...>) // strengthened
+ : __base(in_place, std::forward<_Args>(__args)...) {}
+
+ template <class _Up, class... _Args>
+ requires is_constructible_v< _Tp, initializer_list<_Up>&, _Args... >
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(in_place_t, initializer_list<_Up> __il, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Tp, initializer_list<_Up>&, _Args...>) // strengthened
+ : __base(in_place, __il, std::forward<_Args>(__args)...) {}
+
+ template <class... _Args>
+ requires is_constructible_v<_Err, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(unexpect_t, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Err, _Args...>) // strengthened
+ : __base(unexpect, std::forward<_Args>(__args)...) {}
+
+ template <class _Up, class... _Args>
+ requires is_constructible_v< _Err, initializer_list<_Up>&, _Args... >
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(unexpect_t, initializer_list<_Up> __il, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Err, initializer_list<_Up>&, _Args...>) // strengthened
+ : __base(unexpect, __il, std::forward<_Args>(__args)...) {}
+
+ // [expected.object.dtor], destructor
+
+ _LIBCPP_HIDE_FROM_ABI constexpr ~expected() = default;
+
+private:
+ template <class _Tag, class _OtherTag, class _T1, class _T2, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __reinit_expected(_T2& __oldval, _Args&&... __args) {
+ if constexpr (is_nothrow_constructible_v<_T1, _Args...>) {
+ this->__destroy();
+ this->__construct(_Tag{}, std::forward<_Args>(__args)...);
+ } else if constexpr (is_nothrow_move_constructible_v<_T1>) {
+ _T1 __tmp(std::forward<_Args>(__args)...);
+ this->__destroy();
+ this->__construct(_Tag{}, std::move(__tmp));
+ } else {
+ static_assert(
+ is_nothrow_move_constructible_v<_T2>,
+ "To provide strong exception guarantee, T2 has to satisfy `is_nothrow_move_constructible_v` so that it can "
+ "be reverted to the previous state in case an exception is thrown during the assignment.");
+ _T2 __tmp(std::move(__oldval));
+ this->__destroy();
+ auto __trans = std::__make_exception_guard([&] { this->__construct(_OtherTag{}, std::move(__tmp)); });
+ this->__construct(_Tag{}, std::forward<_Args>(__args)...);
+ __trans.__complete();
+ }
+ }
+
+public:
+ // [expected.object.assign], assignment
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(const expected&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(const expected& __rhs) noexcept(
+ is_nothrow_copy_assignable_v<_Tp> && is_nothrow_copy_constructible_v<_Tp> && is_nothrow_copy_assignable_v<_Err> &&
+ is_nothrow_copy_constructible_v<_Err>) // strengthened
+ requires(is_copy_assignable_v<_Tp> && is_copy_constructible_v<_Tp> && is_copy_assignable_v<_Err> &&
+ is_copy_constructible_v<_Err> &&
+ (is_nothrow_move_constructible_v<_Tp> || is_nothrow_move_constructible_v<_Err>))
+ {
+ if (this->__has_val() && __rhs.__has_val()) {
+ this->__val() = __rhs.__val();
+ } else if (this->__has_val()) {
+ __reinit_expected<unexpect_t, in_place_t, _Err, _Tp>(this->__val(), __rhs.__unex());
+ } else if (__rhs.__has_val()) {
+ __reinit_expected<in_place_t, unexpect_t, _Tp, _Err>(this->__unex(), __rhs.__val());
+ } else {
+ this->__unex() = __rhs.__unex();
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected&
+ operator=(expected&& __rhs) noexcept(is_nothrow_move_assignable_v<_Tp> && is_nothrow_move_constructible_v<_Tp> &&
+ is_nothrow_move_assignable_v<_Err> && is_nothrow_move_constructible_v<_Err>)
+ requires(is_move_constructible_v<_Tp> && is_move_assignable_v<_Tp> && is_move_constructible_v<_Err> &&
+ is_move_assignable_v<_Err> &&
+ (is_nothrow_move_constructible_v<_Tp> || is_nothrow_move_constructible_v<_Err>))
+ {
+ if (this->__has_val() && __rhs.__has_val()) {
+ this->__val() = std::move(__rhs.__val());
+ } else if (this->__has_val()) {
+ __reinit_expected<unexpect_t, in_place_t, _Err, _Tp>(this->__val(), std::move(__rhs.__unex()));
+ } else if (__rhs.__has_val()) {
+ __reinit_expected<in_place_t, unexpect_t, _Tp, _Err>(this->__unex(), std::move(__rhs.__val()));
+ } else {
+ this->__unex() = std::move(__rhs.__unex());
+ }
+ return *this;
+ }
+
+ template <class _Up = _Tp>
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(_Up&& __v)
+ requires(!is_same_v<expected, remove_cvref_t<_Up>> && !__is_std_unexpected<remove_cvref_t<_Up>>::value &&
+ is_constructible_v<_Tp, _Up> && is_assignable_v<_Tp&, _Up> &&
+ (is_nothrow_constructible_v<_Tp, _Up> || is_nothrow_move_constructible_v<_Tp> ||
+ is_nothrow_move_constructible_v<_Err>))
+ {
+ if (this->__has_val()) {
+ this->__val() = std::forward<_Up>(__v);
+ } else {
+ __reinit_expected<in_place_t, unexpect_t, _Tp, _Err>(this->__unex(), std::forward<_Up>(__v));
+ }
+ return *this;
+ }
+
+private:
+ template <class _OtherErrQual>
+ static constexpr bool __can_assign_from_unexpected =
+ _And< is_constructible<_Err, _OtherErrQual>,
+ is_assignable<_Err&, _OtherErrQual>,
+ _Lazy<_Or,
+ is_nothrow_constructible<_Err, _OtherErrQual>,
+ is_nothrow_move_constructible<_Tp>,
+ is_nothrow_move_constructible<_Err>> >::value;
+
+public:
+ template <class _OtherErr>
+ requires(__can_assign_from_unexpected<const _OtherErr&>)
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(const unexpected<_OtherErr>& __un) {
+ if (this->__has_val()) {
+ __reinit_expected<unexpect_t, in_place_t, _Err, _Tp>(this->__val(), __un.error());
+ } else {
+ this->__unex() = __un.error();
+ }
+ return *this;
+ }
+
+ template <class _OtherErr>
+ requires(__can_assign_from_unexpected<_OtherErr>)
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(unexpected<_OtherErr>&& __un) {
+ if (this->__has_val()) {
+ __reinit_expected<unexpect_t, in_place_t, _Err, _Tp>(this->__val(), std::move(__un.error()));
+ } else {
+ this->__unex() = std::move(__un.error());
+ }
+ return *this;
+ }
+
+ template <class... _Args>
+ requires is_nothrow_constructible_v<_Tp, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& emplace(_Args&&... __args) noexcept {
+ this->__destroy();
+ this->__construct(in_place, std::forward<_Args>(__args)...);
+ return this->__val();
+ }
+
+ template <class _Up, class... _Args>
+ requires is_nothrow_constructible_v<_Tp, initializer_list<_Up>&, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& emplace(initializer_list<_Up> __il, _Args&&... __args) noexcept {
+ this->__destroy();
+ this->__construct(in_place, __il, std::forward<_Args>(__args)...);
+ return this->__val();
+ }
+
+public:
+ // [expected.object.swap], swap
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ swap(expected& __rhs) noexcept(is_nothrow_move_constructible_v<_Tp> && is_nothrow_swappable_v<_Tp> &&
+ is_nothrow_move_constructible_v<_Err> && is_nothrow_swappable_v<_Err>)
+ requires(is_swappable_v<_Tp> && is_swappable_v<_Err> && is_move_constructible_v<_Tp> &&
+ is_move_constructible_v<_Err> &&
+ (is_nothrow_move_constructible_v<_Tp> || is_nothrow_move_constructible_v<_Err>))
+ {
+ auto __swap_val_unex_impl = [](expected& __with_val, expected& __with_err) {
+ if constexpr (is_nothrow_move_constructible_v<_Err>) {
+ _Err __tmp(std::move(__with_err.__unex()));
+ __with_err.__destroy();
+ auto __trans = std::__make_exception_guard([&] { __with_err.__construct(unexpect, std::move(__tmp)); });
+ __with_err.__construct(in_place, std::move(__with_val.__val()));
+ __trans.__complete();
+ __with_val.__destroy();
+ __with_val.__construct(unexpect, std::move(__tmp));
+ } else {
+ static_assert(is_nothrow_move_constructible_v<_Tp>,
+ "To provide strong exception guarantee, Tp has to satisfy `is_nothrow_move_constructible_v` so "
+ "that it can be reverted to the previous state in case an exception is thrown during swap.");
+ _Tp __tmp(std::move(__with_val.__val()));
+ __with_val.__destroy();
+ auto __trans = std::__make_exception_guard([&] { __with_val.__construct(in_place, std::move(__tmp)); });
+ __with_val.__construct(unexpect, std::move(__with_err.__unex()));
+ __trans.__complete();
+ __with_err.__destroy();
+ __with_err.__construct(in_place, std::move(__tmp));
+ }
+ };
+
+ if (this->__has_val()) {
+ if (__rhs.__has_val()) {
+ using std::swap;
+ swap(this->__val(), __rhs.__val());
+ } else {
+ __swap_val_unex_impl(*this, __rhs);
+ }
+ } else {
+ if (__rhs.__has_val()) {
+ __swap_val_unex_impl(__rhs, *this);
+ } else {
+ using std::swap;
+ swap(this->__unex(), __rhs.__unex());
+ }
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void swap(expected& __x, expected& __y) noexcept(noexcept(__x.swap(__y)))
+ requires requires { __x.swap(__y); }
+ {
+ __x.swap(__y);
+ }
+
+ // [expected.object.obs], observers
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp* operator->() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ this->__has_val(), "expected::operator-> requires the expected to contain a value");
+ return std::addressof(this->__val());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* operator->() noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ this->__has_val(), "expected::operator-> requires the expected to contain a value");
+ return std::addressof(this->__val());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& operator*() const& noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ this->__has_val(), "expected::operator* requires the expected to contain a value");
+ return this->__val();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& operator*() & noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ this->__has_val(), "expected::operator* requires the expected to contain a value");
+ return this->__val();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp&& operator*() const&& noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ this->__has_val(), "expected::operator* requires the expected to contain a value");
+ return std::move(this->__val());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp&& operator*() && noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ this->__has_val(), "expected::operator* requires the expected to contain a value");
+ return std::move(this->__val());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return this->__has_val(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool has_value() const noexcept { return this->__has_val(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& value() const& {
+ static_assert(is_copy_constructible_v<_Err>, "error_type has to be copy constructible");
+ if (!this->__has_val()) {
+ std::__throw_bad_expected_access<_Err>(std::as_const(error()));
+ }
+ return this->__val();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& value() & {
+ static_assert(is_copy_constructible_v<_Err>, "error_type has to be copy constructible");
+ if (!this->__has_val()) {
+ std::__throw_bad_expected_access<_Err>(std::as_const(error()));
+ }
+ return this->__val();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp&& value() const&& {
+ static_assert(is_copy_constructible_v<_Err> && is_constructible_v<_Err, decltype(std::move(error()))>,
+ "error_type has to be both copy constructible and constructible from decltype(std::move(error()))");
+ if (!this->__has_val()) {
+ std::__throw_bad_expected_access<_Err>(std::move(error()));
+ }
+ return std::move(this->__val());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp&& value() && {
+ static_assert(is_copy_constructible_v<_Err> && is_constructible_v<_Err, decltype(std::move(error()))>,
+ "error_type has to be both copy constructible and constructible from decltype(std::move(error()))");
+ if (!this->__has_val()) {
+ std::__throw_bad_expected_access<_Err>(std::move(error()));
+ }
+ return std::move(this->__val());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Err& error() const& noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !this->__has_val(), "expected::error requires the expected to contain an error");
+ return this->__unex();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err& error() & noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !this->__has_val(), "expected::error requires the expected to contain an error");
+ return this->__unex();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Err&& error() const&& noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !this->__has_val(), "expected::error requires the expected to contain an error");
+ return std::move(this->__unex());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err&& error() && noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !this->__has_val(), "expected::error requires the expected to contain an error");
+ return std::move(this->__unex());
+ }
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp value_or(_Up&& __v) const& {
+ static_assert(is_copy_constructible_v<_Tp>, "value_type has to be copy constructible");
+ static_assert(is_convertible_v<_Up, _Tp>, "argument has to be convertible to value_type");
+ return this->__has_val() ? this->__val() : static_cast<_Tp>(std::forward<_Up>(__v));
+ }
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp value_or(_Up&& __v) && {
+ static_assert(is_move_constructible_v<_Tp>, "value_type has to be move constructible");
+ static_assert(is_convertible_v<_Up, _Tp>, "argument has to be convertible to value_type");
+ return this->__has_val() ? std::move(this->__val()) : static_cast<_Tp>(std::forward<_Up>(__v));
+ }
+
+ template <class _Up = _Err>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err error_or(_Up&& __error) const& {
+ static_assert(is_copy_constructible_v<_Err>, "error_type has to be copy constructible");
+ static_assert(is_convertible_v<_Up, _Err>, "argument has to be convertible to error_type");
+ if (has_value())
+ return std::forward<_Up>(__error);
+ return error();
+ }
+
+ template <class _Up = _Err>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err error_or(_Up&& __error) && {
+ static_assert(is_move_constructible_v<_Err>, "error_type has to be move constructible");
+ static_assert(is_convertible_v<_Up, _Err>, "argument has to be convertible to error_type");
+ if (has_value())
+ return std::forward<_Up>(__error);
+ return std::move(error());
+ }
+
+ // [expected.void.monadic], monadic
+ template <class _Func>
+ requires is_constructible_v<_Err, _Err&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) & {
+ using _Up = remove_cvref_t<invoke_result_t<_Func, _Tp&>>;
+ static_assert(__is_std_expected<_Up>::value, "The result of f(**this) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Up::error_type, _Err>,
+ "The result of f(**this) must have the same error_type as this expected");
+ if (has_value()) {
+ return std::invoke(std::forward<_Func>(__f), this->__val());
+ }
+ return _Up(unexpect, error());
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, const _Err&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) const& {
+ using _Up = remove_cvref_t<invoke_result_t<_Func, const _Tp&>>;
+ static_assert(__is_std_expected<_Up>::value, "The result of f(**this) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Up::error_type, _Err>,
+ "The result of f(**this) must have the same error_type as this expected");
+ if (has_value()) {
+ return std::invoke(std::forward<_Func>(__f), this->__val());
+ }
+ return _Up(unexpect, error());
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, _Err&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) && {
+ using _Up = remove_cvref_t<invoke_result_t<_Func, _Tp&&>>;
+ static_assert(
+ __is_std_expected<_Up>::value, "The result of f(std::move(**this)) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Up::error_type, _Err>,
+ "The result of f(std::move(**this)) must have the same error_type as this expected");
+ if (has_value()) {
+ return std::invoke(std::forward<_Func>(__f), std::move(this->__val()));
+ }
+ return _Up(unexpect, std::move(error()));
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, const _Err&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) const&& {
+ using _Up = remove_cvref_t<invoke_result_t<_Func, const _Tp&&>>;
+ static_assert(
+ __is_std_expected<_Up>::value, "The result of f(std::move(**this)) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Up::error_type, _Err>,
+ "The result of f(std::move(**this)) must have the same error_type as this expected");
+ if (has_value()) {
+ return std::invoke(std::forward<_Func>(__f), std::move(this->__val()));
+ }
+ return _Up(unexpect, std::move(error()));
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Tp, _Tp&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto or_else(_Func&& __f) & {
+ using _Gp = remove_cvref_t<invoke_result_t<_Func, _Err&>>;
+ static_assert(__is_std_expected<_Gp>::value, "The result of f(error()) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Gp::value_type, _Tp>,
+ "The result of f(error()) must have the same value_type as this expected");
+ if (has_value()) {
+ return _Gp(in_place, this->__val());
+ }
+ return std::invoke(std::forward<_Func>(__f), error());
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Tp, const _Tp&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto or_else(_Func&& __f) const& {
+ using _Gp = remove_cvref_t<invoke_result_t<_Func, const _Err&>>;
+ static_assert(__is_std_expected<_Gp>::value, "The result of f(error()) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Gp::value_type, _Tp>,
+ "The result of f(error()) must have the same value_type as this expected");
+ if (has_value()) {
+ return _Gp(in_place, this->__val());
+ }
+ return std::invoke(std::forward<_Func>(__f), error());
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Tp, _Tp&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto or_else(_Func&& __f) && {
+ using _Gp = remove_cvref_t<invoke_result_t<_Func, _Err&&>>;
+ static_assert(
+ __is_std_expected<_Gp>::value, "The result of f(std::move(error())) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Gp::value_type, _Tp>,
+ "The result of f(std::move(error())) must have the same value_type as this expected");
+ if (has_value()) {
+ return _Gp(in_place, std::move(this->__val()));
+ }
+ return std::invoke(std::forward<_Func>(__f), std::move(error()));
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Tp, const _Tp&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto or_else(_Func&& __f) const&& {
+ using _Gp = remove_cvref_t<invoke_result_t<_Func, const _Err&&>>;
+ static_assert(
+ __is_std_expected<_Gp>::value, "The result of f(std::move(error())) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Gp::value_type, _Tp>,
+ "The result of f(std::move(error())) must have the same value_type as this expected");
+ if (has_value()) {
+ return _Gp(in_place, std::move(this->__val()));
+ }
+ return std::invoke(std::forward<_Func>(__f), std::move(error()));
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, _Err&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform(_Func&& __f) & {
+ using _Up = remove_cv_t<invoke_result_t<_Func, _Tp&>>;
+ if (!has_value()) {
+ return expected<_Up, _Err>(unexpect, error());
+ }
+ if constexpr (!is_void_v<_Up>) {
+ return expected<_Up, _Err>(
+ __expected_construct_in_place_from_invoke_tag{}, std::forward<_Func>(__f), this->__val());
+ } else {
+ std::invoke(std::forward<_Func>(__f), this->__val());
+ return expected<_Up, _Err>();
+ }
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, const _Err&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform(_Func&& __f) const& {
+ using _Up = remove_cv_t<invoke_result_t<_Func, const _Tp&>>;
+ if (!has_value()) {
+ return expected<_Up, _Err>(unexpect, error());
+ }
+ if constexpr (!is_void_v<_Up>) {
+ return expected<_Up, _Err>(
+ __expected_construct_in_place_from_invoke_tag{}, std::forward<_Func>(__f), this->__val());
+ } else {
+ std::invoke(std::forward<_Func>(__f), this->__val());
+ return expected<_Up, _Err>();
+ }
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, _Err&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform(_Func&& __f) && {
+ using _Up = remove_cv_t<invoke_result_t<_Func, _Tp&&>>;
+ if (!has_value()) {
+ return expected<_Up, _Err>(unexpect, std::move(error()));
+ }
+ if constexpr (!is_void_v<_Up>) {
+ return expected<_Up, _Err>(
+ __expected_construct_in_place_from_invoke_tag{}, std::forward<_Func>(__f), std::move(this->__val()));
+ } else {
+ std::invoke(std::forward<_Func>(__f), std::move(this->__val()));
+ return expected<_Up, _Err>();
+ }
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, const _Err&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform(_Func&& __f) const&& {
+ using _Up = remove_cv_t<invoke_result_t<_Func, const _Tp&&>>;
+ if (!has_value()) {
+ return expected<_Up, _Err>(unexpect, std::move(error()));
+ }
+ if constexpr (!is_void_v<_Up>) {
+ return expected<_Up, _Err>(
+ __expected_construct_in_place_from_invoke_tag{}, std::forward<_Func>(__f), std::move(this->__val()));
+ } else {
+ std::invoke(std::forward<_Func>(__f), std::move(this->__val()));
+ return expected<_Up, _Err>();
+ }
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Tp, _Tp&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform_error(_Func&& __f) & {
+ using _Gp = remove_cv_t<invoke_result_t<_Func, _Err&>>;
+ static_assert(__valid_std_unexpected<_Gp>::value,
+ "The result of f(error()) must be a valid template argument for unexpected");
+ if (has_value()) {
+ return expected<_Tp, _Gp>(in_place, this->__val());
+ }
+ return expected<_Tp, _Gp>(__expected_construct_unexpected_from_invoke_tag{}, std::forward<_Func>(__f), error());
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Tp, const _Tp&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform_error(_Func&& __f) const& {
+ using _Gp = remove_cv_t<invoke_result_t<_Func, const _Err&>>;
+ static_assert(__valid_std_unexpected<_Gp>::value,
+ "The result of f(error()) must be a valid template argument for unexpected");
+ if (has_value()) {
+ return expected<_Tp, _Gp>(in_place, this->__val());
+ }
+ return expected<_Tp, _Gp>(__expected_construct_unexpected_from_invoke_tag{}, std::forward<_Func>(__f), error());
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Tp, _Tp&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform_error(_Func&& __f) && {
+ using _Gp = remove_cv_t<invoke_result_t<_Func, _Err&&>>;
+ static_assert(__valid_std_unexpected<_Gp>::value,
+ "The result of f(std::move(error())) must be a valid template argument for unexpected");
+ if (has_value()) {
+ return expected<_Tp, _Gp>(in_place, std::move(this->__val()));
+ }
+ return expected<_Tp, _Gp>(
+ __expected_construct_unexpected_from_invoke_tag{}, std::forward<_Func>(__f), std::move(error()));
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Tp, const _Tp&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform_error(_Func&& __f) const&& {
+ using _Gp = remove_cv_t<invoke_result_t<_Func, const _Err&&>>;
+ static_assert(__valid_std_unexpected<_Gp>::value,
+ "The result of f(std::move(error())) must be a valid template argument for unexpected");
+ if (has_value()) {
+ return expected<_Tp, _Gp>(in_place, std::move(this->__val()));
+ }
+ return expected<_Tp, _Gp>(
+ __expected_construct_unexpected_from_invoke_tag{}, std::forward<_Func>(__f), std::move(error()));
+ }
+
+ // [expected.object.eq], equality operators
+ template <class _T2, class _E2>
+ requires(!is_void_v<_T2>)
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const expected& __x, const expected<_T2, _E2>& __y) {
+ if (__x.__has_val() != __y.__has_val()) {
+ return false;
+ } else {
+ if (__x.__has_val()) {
+ return __x.__val() == __y.__val();
+ } else {
+ return __x.__unex() == __y.__unex();
+ }
+ }
+ }
+
+ template <class _T2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const expected& __x, const _T2& __v) {
+ return __x.__has_val() && static_cast<bool>(__x.__val() == __v);
+ }
+
+ template <class _E2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const expected& __x, const unexpected<_E2>& __e) {
+ return !__x.__has_val() && static_cast<bool>(__x.__unex() == __e.error());
+ }
+};
+
+template <class _Err>
+class __expected_void_base {
+ struct __empty_t {};
+ // use named union because [[no_unique_address]] cannot be applied to an unnamed union,
+ // also guaranteed elision into a potentially-overlapping subobject is unsettled (and
+ // it's not clear that it's implementable, given that the function is allowed to clobber
+ // the tail padding) - see https://github.com/itanium-cxx-abi/cxx-abi/issues/107.
+ union __union_t {
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t(const __union_t&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t(const __union_t&)
+ requires(is_copy_constructible_v<_Err> && is_trivially_copy_constructible_v<_Err>)
+ = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t(__union_t&&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t(__union_t&&)
+ requires(is_move_constructible_v<_Err> && is_trivially_move_constructible_v<_Err>)
+ = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t& operator=(const __union_t&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t& operator=(__union_t&&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __union_t(in_place_t) : __empty_() {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __union_t(unexpect_t, _Args&&... __args)
+ : __unex_(std::forward<_Args>(__args)...) {}
+
+ template <class _Func, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __union_t(
+ __expected_construct_unexpected_from_invoke_tag, _Func&& __f, _Args&&... __args)
+ : __unex_(std::invoke(std::forward<_Func>(__f), std::forward<_Args>(__args)...)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr ~__union_t()
+ requires(is_trivially_destructible_v<_Err>)
+ = default;
+
+ // __repr's destructor handles this
+ _LIBCPP_HIDE_FROM_ABI constexpr ~__union_t()
+ requires(!is_trivially_destructible_v<_Err>)
+ {}
+
+ _LIBCPP_NO_UNIQUE_ADDRESS __empty_t __empty_;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Err __unex_;
+ };
+
+ static constexpr bool __put_flag_in_tail = __fits_in_tail_padding<__union_t, bool>;
+ static constexpr bool __allow_reusing_expected_tail_padding = !__put_flag_in_tail;
+
+ struct __repr {
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr() = delete;
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(in_place_t __tag) : __union_(in_place, __tag), __has_val_(true) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(unexpect_t __tag, _Args&&... __args)
+ : __union_(in_place, __tag, std::forward<_Args>(__args)...), __has_val_(false) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(std::__expected_construct_unexpected_from_invoke_tag __tag,
+ _Args&&... __args)
+ : __union_(in_place, __tag, std::forward<_Args>(__args)...), __has_val_(false) {}
+
+ template <class _OtherUnion>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __repr(bool __has_val, _OtherUnion&& __other)
+ requires(__allow_reusing_expected_tail_padding)
+ : __union_(__conditional_no_unique_address_invoke_tag{},
+ [&] { return __make_union(__has_val, std::forward<_OtherUnion>(__other)); }),
+ __has_val_(__has_val) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr(const __repr&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr(const __repr&)
+ requires(is_copy_constructible_v<_Err> && is_trivially_copy_constructible_v<_Err>)
+ = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr(__repr&&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr(__repr&&)
+ requires(is_move_constructible_v<_Err> && is_trivially_move_constructible_v<_Err>)
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr& operator=(const __repr&) = delete;
+ _LIBCPP_HIDE_FROM_ABI constexpr __repr& operator=(__repr&&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr ~__repr()
+ requires(is_trivially_destructible_v<_Err>)
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr ~__repr()
+ requires(!is_trivially_destructible_v<_Err>)
+ {
+ __destroy_union_member();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __destroy_union()
+ requires(__allow_reusing_expected_tail_padding && is_trivially_destructible_v<_Err>)
+ {
+ std::destroy_at(&__union_.__v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __destroy_union()
+ requires(__allow_reusing_expected_tail_padding && !is_trivially_destructible_v<_Err>)
+ {
+ __destroy_union_member();
+ std::destroy_at(&__union_.__v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __construct_union(in_place_t)
+ requires(__allow_reusing_expected_tail_padding)
+ {
+ std::construct_at(&__union_.__v, in_place);
+ __has_val_ = true;
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __construct_union(unexpect_t, _Args&&... __args)
+ requires(__allow_reusing_expected_tail_padding)
+ {
+ std::construct_at(&__union_.__v, unexpect, std::forward<_Args>(__args)...);
+ __has_val_ = false;
+ }
+
+ private:
+ template <class>
+ friend class __expected_void_base;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __destroy_union_member()
+ requires(!is_trivially_destructible_v<_Err>)
+ {
+ if (!__has_val_)
+ std::destroy_at(std::addressof(__union_.__v.__unex_));
+ }
+
+ template <class _OtherUnion>
+ _LIBCPP_HIDE_FROM_ABI static constexpr __union_t __make_union(bool __has_val, _OtherUnion&& __other)
+ requires(__allow_reusing_expected_tail_padding)
+ {
+ if (__has_val)
+ return __union_t(in_place);
+ else
+ return __union_t(unexpect, std::forward<_OtherUnion>(__other).__unex_);
+ }
+
+ _LIBCPP_NO_UNIQUE_ADDRESS __conditional_no_unique_address<__put_flag_in_tail, __union_t> __union_;
+ _LIBCPP_NO_UNIQUE_ADDRESS bool __has_val_;
+ };
+
+ template <class _OtherUnion>
+ _LIBCPP_HIDE_FROM_ABI static constexpr __repr __make_repr(bool __has_val, _OtherUnion&& __other)
+ requires(__put_flag_in_tail)
+ {
+ if (__has_val)
+ return __repr(in_place);
+ else
+ return __repr(unexpect, std::forward<_OtherUnion>(__other).__unex_);
+ }
+
+protected:
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __expected_void_base(_Args&&... __args)
+ : __repr_(in_place, std::forward<_Args>(__args)...) {}
+
+ template <class _OtherUnion>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __expected_void_base(bool __has_val, _OtherUnion&& __other)
+ requires(__put_flag_in_tail)
+ : __repr_(__conditional_no_unique_address_invoke_tag{},
+ [&] { return __make_repr(__has_val, std::forward<_OtherUnion>(__other)); }) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __destroy() {
+ if constexpr (__put_flag_in_tail)
+ std::destroy_at(&__repr_.__v);
+ else
+ __repr_.__v.__destroy_union();
+ }
+
+ template <class _Tag, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __construct(_Tag __tag, _Args&&... __args) {
+ if constexpr (__put_flag_in_tail)
+ std::construct_at(&__repr_.__v, __tag, std::forward<_Args>(__args)...);
+ else
+ __repr_.__v.__construct_union(__tag, std::forward<_Args>(__args)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __has_val() const { return __repr_.__v.__has_val_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr __union_t& __union() { return __repr_.__v.__union_.__v; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const __union_t& __union() const { return __repr_.__v.__union_.__v; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err& __unex() { return __repr_.__v.__union_.__v.__unex_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Err& __unex() const { return __repr_.__v.__union_.__v.__unex_; }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS __conditional_no_unique_address<__allow_reusing_expected_tail_padding, __repr> __repr_;
+};
+
+template <class _Tp, class _Err>
+ requires is_void_v<_Tp>
+class expected<_Tp, _Err> : private __expected_void_base<_Err> {
+ static_assert(__valid_std_unexpected<_Err>::value,
+ "[expected.void.general] A program that instantiates expected<T, E> with a E that is not a "
+ "valid argument for unexpected<E> is ill-formed");
+
+ template <class, class>
+ friend class expected;
+
+ template <class _Up, class _OtherErr, class _OtherErrQual>
+ using __can_convert =
+ _And< is_void<_Up>,
+ is_constructible<_Err, _OtherErrQual>,
+ _Not<is_constructible<unexpected<_Err>, expected<_Up, _OtherErr>&>>,
+ _Not<is_constructible<unexpected<_Err>, expected<_Up, _OtherErr>>>,
+ _Not<is_constructible<unexpected<_Err>, const expected<_Up, _OtherErr>&>>,
+ _Not<is_constructible<unexpected<_Err>, const expected<_Up, _OtherErr>>>>;
+
+ using __base = __expected_void_base<_Err>;
+
+public:
+ using value_type = _Tp;
+ using error_type = _Err;
+ using unexpected_type = unexpected<_Err>;
+
+ template <class _Up>
+ using rebind = expected<_Up, error_type>;
+
+ // [expected.void.ctor], constructors
+ _LIBCPP_HIDE_FROM_ABI constexpr expected() noexcept : __base(in_place) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(const expected&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(const expected&)
+ requires(is_copy_constructible_v<_Err> && is_trivially_copy_constructible_v<_Err>)
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(const expected& __rhs) noexcept(
+ is_nothrow_copy_constructible_v<_Err>) // strengthened
+ requires(is_copy_constructible_v<_Err> && !is_trivially_copy_constructible_v<_Err>)
+ : __base(__rhs.__has_val(), __rhs.__union()) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(expected&&)
+ requires(is_move_constructible_v<_Err> && is_trivially_move_constructible_v<_Err>)
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected(expected&& __rhs) noexcept(is_nothrow_move_constructible_v<_Err>)
+ requires(is_move_constructible_v<_Err> && !is_trivially_move_constructible_v<_Err>)
+ : __base(__rhs.__has_val(), std::move(__rhs.__union())) {}
+
+ template <class _Up, class _OtherErr>
+ requires __can_convert<_Up, _OtherErr, const _OtherErr&>::value
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<const _OtherErr&, _Err>)
+ expected(const expected<_Up, _OtherErr>& __rhs) noexcept(
+ is_nothrow_constructible_v<_Err, const _OtherErr&>) // strengthened
+ : __base(__rhs.__has_val(), __rhs.__union()) {}
+
+ template <class _Up, class _OtherErr>
+ requires __can_convert<_Up, _OtherErr, _OtherErr>::value
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_OtherErr, _Err>)
+ expected(expected<_Up, _OtherErr>&& __rhs) noexcept(is_nothrow_constructible_v<_Err, _OtherErr>) // strengthened
+ : __base(__rhs.__has_val(), std::move(__rhs.__union())) {}
+
+ template <class _OtherErr>
+ requires is_constructible_v<_Err, const _OtherErr&>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<const _OtherErr&, _Err>) expected(
+ const unexpected<_OtherErr>& __unex) noexcept(is_nothrow_constructible_v<_Err, const _OtherErr&>) // strengthened
+ : __base(unexpect, __unex.error()) {}
+
+ template <class _OtherErr>
+ requires is_constructible_v<_Err, _OtherErr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_OtherErr, _Err>)
+ expected(unexpected<_OtherErr>&& __unex) noexcept(is_nothrow_constructible_v<_Err, _OtherErr>) // strengthened
+ : __base(unexpect, std::move(__unex.error())) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(in_place_t) noexcept : __base(in_place) {}
+
+ template <class... _Args>
+ requires is_constructible_v<_Err, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(unexpect_t, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Err, _Args...>) // strengthened
+ : __base(unexpect, std::forward<_Args>(__args)...) {}
+
+ template <class _Up, class... _Args>
+ requires is_constructible_v< _Err, initializer_list<_Up>&, _Args... >
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(unexpect_t, initializer_list<_Up> __il, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Err, initializer_list<_Up>&, _Args...>) // strengthened
+ : __base(unexpect, __il, std::forward<_Args>(__args)...) {}
+
+private:
+ template <class _Func, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit expected(
+ __expected_construct_unexpected_from_invoke_tag __tag, _Func&& __f, _Args&&... __args)
+ : __base(__tag, std::forward<_Func>(__f), std::forward<_Args>(__args)...) {}
+
+public:
+ // [expected.void.dtor], destructor
+
+ _LIBCPP_HIDE_FROM_ABI constexpr ~expected() = default;
+
+private:
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __reinit_expected(unexpect_t, _Args&&... __args) {
+ _LIBCPP_ASSERT_INTERNAL(this->__has_val(), "__reinit_expected(unexpect_t, ...) needs value to be set");
+
+ this->__destroy();
+ auto __trans = std::__make_exception_guard([&] { this->__construct(in_place); });
+ this->__construct(unexpect, std::forward<_Args>(__args)...);
+ __trans.__complete();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __reinit_expected(in_place_t) {
+ _LIBCPP_ASSERT_INTERNAL(!this->__has_val(), "__reinit_expected(in_place_t, ...) needs value to be unset");
+
+ this->__destroy();
+ this->__construct(in_place);
+ }
+
+public:
+ // [expected.void.assign], assignment
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(const expected&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(const expected& __rhs) noexcept(
+ is_nothrow_copy_assignable_v<_Err> && is_nothrow_copy_constructible_v<_Err>) // strengthened
+ requires(is_copy_assignable_v<_Err> && is_copy_constructible_v<_Err>)
+ {
+ if (this->__has_val()) {
+ if (!__rhs.__has_val()) {
+ __reinit_expected(unexpect, __rhs.__unex());
+ }
+ } else {
+ if (__rhs.__has_val()) {
+ __reinit_expected(in_place);
+ } else {
+ this->__unex() = __rhs.__unex();
+ }
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(expected&&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr expected&
+ operator=(expected&& __rhs) noexcept(is_nothrow_move_assignable_v<_Err> && is_nothrow_move_constructible_v<_Err>)
+ requires(is_move_assignable_v<_Err> && is_move_constructible_v<_Err>)
+ {
+ if (this->__has_val()) {
+ if (!__rhs.__has_val()) {
+ __reinit_expected(unexpect, std::move(__rhs.__unex()));
+ }
+ } else {
+ if (__rhs.__has_val()) {
+ __reinit_expected(in_place);
+ } else {
+ this->__unex() = std::move(__rhs.__unex());
+ }
+ }
+ return *this;
+ }
+
+ template <class _OtherErr>
+ requires(is_constructible_v<_Err, const _OtherErr&> && is_assignable_v<_Err&, const _OtherErr&>)
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(const unexpected<_OtherErr>& __un) {
+ if (this->__has_val()) {
+ __reinit_expected(unexpect, __un.error());
+ } else {
+ this->__unex() = __un.error();
+ }
+ return *this;
+ }
+
+ template <class _OtherErr>
+ requires(is_constructible_v<_Err, _OtherErr> && is_assignable_v<_Err&, _OtherErr>)
+ _LIBCPP_HIDE_FROM_ABI constexpr expected& operator=(unexpected<_OtherErr>&& __un) {
+ if (this->__has_val()) {
+ __reinit_expected(unexpect, std::move(__un.error()));
+ } else {
+ this->__unex() = std::move(__un.error());
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void emplace() noexcept {
+ if (!this->__has_val()) {
+ __reinit_expected(in_place);
+ }
+ }
+
+ // [expected.void.swap], swap
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ swap(expected& __rhs) noexcept(is_nothrow_move_constructible_v<_Err> && is_nothrow_swappable_v<_Err>)
+ requires(is_swappable_v<_Err> && is_move_constructible_v<_Err>)
+ {
+ auto __swap_val_unex_impl = [](expected& __with_val, expected& __with_err) {
+ // May throw, but will re-engage `__with_val` in that case.
+ __with_val.__reinit_expected(unexpect, std::move(__with_err.__unex()));
+ // Will not throw.
+ __with_err.__reinit_expected(in_place);
+ };
+
+ if (this->__has_val()) {
+ if (!__rhs.__has_val()) {
+ __swap_val_unex_impl(*this, __rhs);
+ }
+ } else {
+ if (__rhs.__has_val()) {
+ __swap_val_unex_impl(__rhs, *this);
+ } else {
+ using std::swap;
+ swap(this->__unex(), __rhs.__unex());
+ }
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void swap(expected& __x, expected& __y) noexcept(noexcept(__x.swap(__y)))
+ requires requires { __x.swap(__y); }
+ {
+ __x.swap(__y);
+ }
+
+ // [expected.void.obs], observers
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return this->__has_val(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool has_value() const noexcept { return this->__has_val(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator*() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ this->__has_val(), "expected::operator* requires the expected to contain a value");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void value() const& {
+ static_assert(is_copy_constructible_v<_Err>);
+ if (!this->__has_val()) {
+ std::__throw_bad_expected_access<_Err>(this->__unex());
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void value() && {
+ static_assert(is_copy_constructible_v<_Err> && is_move_constructible_v<_Err>);
+ if (!this->__has_val()) {
+ std::__throw_bad_expected_access<_Err>(std::move(this->__unex()));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Err& error() const& noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !this->__has_val(), "expected::error requires the expected to contain an error");
+ return this->__unex();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err& error() & noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !this->__has_val(), "expected::error requires the expected to contain an error");
+ return this->__unex();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Err&& error() const&& noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !this->__has_val(), "expected::error requires the expected to contain an error");
+ return std::move(this->__unex());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err&& error() && noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !this->__has_val(), "expected::error requires the expected to contain an error");
+ return std::move(this->__unex());
+ }
+
+ template <class _Up = _Err>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err error_or(_Up&& __error) const& {
+ static_assert(is_copy_constructible_v<_Err>, "error_type has to be copy constructible");
+ static_assert(is_convertible_v<_Up, _Err>, "argument has to be convertible to error_type");
+ if (has_value()) {
+ return std::forward<_Up>(__error);
+ }
+ return error();
+ }
+
+ template <class _Up = _Err>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err error_or(_Up&& __error) && {
+ static_assert(is_move_constructible_v<_Err>, "error_type has to be move constructible");
+ static_assert(is_convertible_v<_Up, _Err>, "argument has to be convertible to error_type");
+ if (has_value()) {
+ return std::forward<_Up>(__error);
+ }
+ return std::move(error());
+ }
+
+ // [expected.void.monadic], monadic
+ template <class _Func>
+ requires is_constructible_v<_Err, _Err&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) & {
+ using _Up = remove_cvref_t<invoke_result_t<_Func>>;
+ static_assert(__is_std_expected<_Up>::value, "The result of f() must be a specialization of std::expected");
+ static_assert(
+ is_same_v<typename _Up::error_type, _Err>, "The result of f() must have the same error_type as this expected");
+ if (has_value()) {
+ return std::invoke(std::forward<_Func>(__f));
+ }
+ return _Up(unexpect, error());
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, const _Err&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) const& {
+ using _Up = remove_cvref_t<invoke_result_t<_Func>>;
+ static_assert(__is_std_expected<_Up>::value, "The result of f() must be a specialization of std::expected");
+ static_assert(
+ is_same_v<typename _Up::error_type, _Err>, "The result of f() must have the same error_type as this expected");
+ if (has_value()) {
+ return std::invoke(std::forward<_Func>(__f));
+ }
+ return _Up(unexpect, error());
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, _Err&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) && {
+ using _Up = remove_cvref_t<invoke_result_t<_Func>>;
+ static_assert(__is_std_expected<_Up>::value, "The result of f() must be a specialization of std::expected");
+ static_assert(
+ is_same_v<typename _Up::error_type, _Err>, "The result of f() must have the same error_type as this expected");
+ if (has_value()) {
+ return std::invoke(std::forward<_Func>(__f));
+ }
+ return _Up(unexpect, std::move(error()));
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, const _Err&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) const&& {
+ using _Up = remove_cvref_t<invoke_result_t<_Func>>;
+ static_assert(__is_std_expected<_Up>::value, "The result of f() must be a specialization of std::expected");
+ static_assert(
+ is_same_v<typename _Up::error_type, _Err>, "The result of f() must have the same error_type as this expected");
+ if (has_value()) {
+ return std::invoke(std::forward<_Func>(__f));
+ }
+ return _Up(unexpect, std::move(error()));
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto or_else(_Func&& __f) & {
+ using _Gp = remove_cvref_t<invoke_result_t<_Func, _Err&>>;
+ static_assert(__is_std_expected<_Gp>::value, "The result of f(error()) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Gp::value_type, _Tp>,
+ "The result of f(error()) must have the same value_type as this expected");
+ if (has_value()) {
+ return _Gp();
+ }
+ return std::invoke(std::forward<_Func>(__f), error());
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto or_else(_Func&& __f) const& {
+ using _Gp = remove_cvref_t<invoke_result_t<_Func, const _Err&>>;
+ static_assert(__is_std_expected<_Gp>::value, "The result of f(error()) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Gp::value_type, _Tp>,
+ "The result of f(error()) must have the same value_type as this expected");
+ if (has_value()) {
+ return _Gp();
+ }
+ return std::invoke(std::forward<_Func>(__f), error());
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto or_else(_Func&& __f) && {
+ using _Gp = remove_cvref_t<invoke_result_t<_Func, _Err&&>>;
+ static_assert(
+ __is_std_expected<_Gp>::value, "The result of f(std::move(error())) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Gp::value_type, _Tp>,
+ "The result of f(std::move(error())) must have the same value_type as this expected");
+ if (has_value()) {
+ return _Gp();
+ }
+ return std::invoke(std::forward<_Func>(__f), std::move(error()));
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto or_else(_Func&& __f) const&& {
+ using _Gp = remove_cvref_t<invoke_result_t<_Func, const _Err&&>>;
+ static_assert(
+ __is_std_expected<_Gp>::value, "The result of f(std::move(error())) must be a specialization of std::expected");
+ static_assert(is_same_v<typename _Gp::value_type, _Tp>,
+ "The result of f(std::move(error())) must have the same value_type as this expected");
+ if (has_value()) {
+ return _Gp();
+ }
+ return std::invoke(std::forward<_Func>(__f), std::move(error()));
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, _Err&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform(_Func&& __f) & {
+ using _Up = remove_cv_t<invoke_result_t<_Func>>;
+ if (!has_value()) {
+ return expected<_Up, _Err>(unexpect, error());
+ }
+ if constexpr (!is_void_v<_Up>) {
+ return expected<_Up, _Err>(__expected_construct_in_place_from_invoke_tag{}, std::forward<_Func>(__f));
+ } else {
+ std::invoke(std::forward<_Func>(__f));
+ return expected<_Up, _Err>();
+ }
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, const _Err&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform(_Func&& __f) const& {
+ using _Up = remove_cv_t<invoke_result_t<_Func>>;
+ if (!has_value()) {
+ return expected<_Up, _Err>(unexpect, error());
+ }
+ if constexpr (!is_void_v<_Up>) {
+ return expected<_Up, _Err>(__expected_construct_in_place_from_invoke_tag{}, std::forward<_Func>(__f));
+ } else {
+ std::invoke(std::forward<_Func>(__f));
+ return expected<_Up, _Err>();
+ }
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, _Err&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform(_Func&& __f) && {
+ using _Up = remove_cv_t<invoke_result_t<_Func>>;
+ if (!has_value()) {
+ return expected<_Up, _Err>(unexpect, std::move(error()));
+ }
+ if constexpr (!is_void_v<_Up>) {
+ return expected<_Up, _Err>(__expected_construct_in_place_from_invoke_tag{}, std::forward<_Func>(__f));
+ } else {
+ std::invoke(std::forward<_Func>(__f));
+ return expected<_Up, _Err>();
+ }
+ }
+
+ template <class _Func>
+ requires is_constructible_v<_Err, const _Err&&>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform(_Func&& __f) const&& {
+ using _Up = remove_cv_t<invoke_result_t<_Func>>;
+ if (!has_value()) {
+ return expected<_Up, _Err>(unexpect, std::move(error()));
+ }
+ if constexpr (!is_void_v<_Up>) {
+ return expected<_Up, _Err>(__expected_construct_in_place_from_invoke_tag{}, std::forward<_Func>(__f));
+ } else {
+ std::invoke(std::forward<_Func>(__f));
+ return expected<_Up, _Err>();
+ }
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform_error(_Func&& __f) & {
+ using _Gp = remove_cv_t<invoke_result_t<_Func, _Err&>>;
+ static_assert(__valid_std_unexpected<_Gp>::value,
+ "The result of f(error()) must be a valid template argument for unexpected");
+ if (has_value()) {
+ return expected<_Tp, _Gp>();
+ }
+ return expected<_Tp, _Gp>(__expected_construct_unexpected_from_invoke_tag{}, std::forward<_Func>(__f), error());
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform_error(_Func&& __f) const& {
+ using _Gp = remove_cv_t<invoke_result_t<_Func, const _Err&>>;
+ static_assert(__valid_std_unexpected<_Gp>::value,
+ "The result of f(error()) must be a valid template argument for unexpected");
+ if (has_value()) {
+ return expected<_Tp, _Gp>();
+ }
+ return expected<_Tp, _Gp>(__expected_construct_unexpected_from_invoke_tag{}, std::forward<_Func>(__f), error());
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform_error(_Func&& __f) && {
+ using _Gp = remove_cv_t<invoke_result_t<_Func, _Err&&>>;
+ static_assert(__valid_std_unexpected<_Gp>::value,
+ "The result of f(std::move(error())) must be a valid template argument for unexpected");
+ if (has_value()) {
+ return expected<_Tp, _Gp>();
+ }
+ return expected<_Tp, _Gp>(
+ __expected_construct_unexpected_from_invoke_tag{}, std::forward<_Func>(__f), std::move(error()));
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto transform_error(_Func&& __f) const&& {
+ using _Gp = remove_cv_t<invoke_result_t<_Func, const _Err&&>>;
+ static_assert(__valid_std_unexpected<_Gp>::value,
+ "The result of f(std::move(error())) must be a valid template argument for unexpected");
+ if (has_value()) {
+ return expected<_Tp, _Gp>();
+ }
+ return expected<_Tp, _Gp>(
+ __expected_construct_unexpected_from_invoke_tag{}, std::forward<_Func>(__f), std::move(error()));
+ }
+
+ // [expected.void.eq], equality operators
+ template <class _T2, class _E2>
+ requires is_void_v<_T2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const expected& __x, const expected<_T2, _E2>& __y) {
+ if (__x.__has_val() != __y.__has_val()) {
+ return false;
+ } else {
+ return __x.__has_val() || static_cast<bool>(__x.__unex() == __y.__unex());
+ }
+ }
+
+ template <class _E2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const expected& __x, const unexpected<_E2>& __y) {
+ return !__x.__has_val() && static_cast<bool>(__x.__unex() == __y.error());
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___EXPECTED_EXPECTED_H
diff --git a/libcxx/include/__cxx03/__expected/unexpect.h b/libcxx/include/__cxx03/__expected/unexpect.h
new file mode 100644
index 00000000000000..df52787d36faff
--- /dev/null
+++ b/libcxx/include/__cxx03/__expected/unexpect.h
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef _LIBCPP___EXPECTED_UNEXPECT_H
+#define _LIBCPP___EXPECTED_UNEXPECT_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct unexpect_t {
+ explicit unexpect_t() = default;
+};
+
+inline constexpr unexpect_t unexpect{};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+#endif // _LIBCPP___EXPECTED_UNEXPECT_H
diff --git a/libcxx/include/__cxx03/__expected/unexpected.h b/libcxx/include/__cxx03/__expected/unexpected.h
new file mode 100644
index 00000000000000..c7fe3c52e43114
--- /dev/null
+++ b/libcxx/include/__cxx03/__expected/unexpected.h
@@ -0,0 +1,127 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef _LIBCPP___EXPECTED_UNEXPECTED_H
+#define _LIBCPP___EXPECTED_UNEXPECTED_H
+
+#include <__config>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/is_volatile.h>
+#include <__type_traits/negation.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Err>
+class unexpected;
+
+template <class _Tp>
+struct __is_std_unexpected : false_type {};
+
+template <class _Err>
+struct __is_std_unexpected<unexpected<_Err>> : true_type {};
+
+template <class _Tp>
+using __valid_std_unexpected = _BoolConstant< //
+ is_object_v<_Tp> && //
+ !is_array_v<_Tp> && //
+ !__is_std_unexpected<_Tp>::value && //
+ !is_const_v<_Tp> && //
+ !is_volatile_v<_Tp> //
+ >;
+
+template <class _Err>
+class unexpected {
+ static_assert(__valid_std_unexpected<_Err>::value,
+ "[expected.un.general] states a program that instantiates std::unexpected for a non-object type, an "
+ "array type, a specialization of unexpected, or a cv-qualified type is ill-formed.");
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr unexpected(const unexpected&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr unexpected(unexpected&&) = default;
+
+ template <class _Error = _Err>
+ requires(!is_same_v<remove_cvref_t<_Error>, unexpected> && //
+ !is_same_v<remove_cvref_t<_Error>, in_place_t> && //
+ is_constructible_v<_Err, _Error>)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit unexpected(_Error&& __error) //
+ noexcept(is_nothrow_constructible_v<_Err, _Error>) // strengthened
+ : __unex_(std::forward<_Error>(__error)) {}
+
+ template <class... _Args>
+ requires is_constructible_v<_Err, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit unexpected(in_place_t, _Args&&... __args) //
+ noexcept(is_nothrow_constructible_v<_Err, _Args...>) // strengthened
+ : __unex_(std::forward<_Args>(__args)...) {}
+
+ template <class _Up, class... _Args>
+ requires is_constructible_v<_Err, initializer_list<_Up>&, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit unexpected(in_place_t, initializer_list<_Up> __il, _Args&&... __args) //
+ noexcept(is_nothrow_constructible_v<_Err, initializer_list<_Up>&, _Args...>) // strengthened
+ : __unex_(__il, std::forward<_Args>(__args)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr unexpected& operator=(const unexpected&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr unexpected& operator=(unexpected&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Err& error() const& noexcept { return __unex_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err& error() & noexcept { return __unex_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Err&& error() const&& noexcept { return std::move(__unex_); }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Err&& error() && noexcept { return std::move(__unex_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void swap(unexpected& __other) noexcept(is_nothrow_swappable_v<_Err>) {
+ static_assert(is_swappable_v<_Err>, "unexpected::swap requires is_swappable_v<E> to be true");
+ using std::swap;
+ swap(__unex_, __other.__unex_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void swap(unexpected& __x, unexpected& __y) noexcept(noexcept(__x.swap(__y)))
+ requires is_swappable_v<_Err>
+ {
+ __x.swap(__y);
+ }
+
+ template <class _Err2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const unexpected& __x, const unexpected<_Err2>& __y) {
+ return __x.__unex_ == __y.__unex_;
+ }
+
+private:
+ _Err __unex_;
+};
+
+template <class _Err>
+unexpected(_Err) -> unexpected<_Err>;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___EXPECTED_UNEXPECTED_H
diff --git a/libcxx/include/__cxx03/__filesystem/copy_options.h b/libcxx/include/__cxx03/__filesystem/copy_options.h
new file mode 100644
index 00000000000000..097eebe61137d7
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/copy_options.h
@@ -0,0 +1,69 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_COPY_OPTIONS_H
+#define _LIBCPP___FILESYSTEM_COPY_OPTIONS_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+enum class copy_options : unsigned short {
+ none = 0,
+ skip_existing = 1,
+ overwrite_existing = 2,
+ update_existing = 4,
+ recursive = 8,
+ copy_symlinks = 16,
+ skip_symlinks = 32,
+ directories_only = 64,
+ create_symlinks = 128,
+ create_hard_links = 256,
+ __in_recursive_copy = 512,
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr copy_options operator&(copy_options __lhs, copy_options __rhs) {
+ return static_cast<copy_options>(static_cast<unsigned short>(__lhs) & static_cast<unsigned short>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr copy_options operator|(copy_options __lhs, copy_options __rhs) {
+ return static_cast<copy_options>(static_cast<unsigned short>(__lhs) | static_cast<unsigned short>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr copy_options operator^(copy_options __lhs, copy_options __rhs) {
+ return static_cast<copy_options>(static_cast<unsigned short>(__lhs) ^ static_cast<unsigned short>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr copy_options operator~(copy_options __lhs) {
+ return static_cast<copy_options>(~static_cast<unsigned short>(__lhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline copy_options& operator&=(copy_options& __lhs, copy_options __rhs) {
+ return __lhs = __lhs & __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline copy_options& operator|=(copy_options& __lhs, copy_options __rhs) {
+ return __lhs = __lhs | __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline copy_options& operator^=(copy_options& __lhs, copy_options __rhs) {
+ return __lhs = __lhs ^ __rhs;
+}
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_COPY_OPTIONS_H
diff --git a/libcxx/include/__cxx03/__filesystem/directory_entry.h b/libcxx/include/__cxx03/__filesystem/directory_entry.h
new file mode 100644
index 00000000000000..96d88dcd90b4c0
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/directory_entry.h
@@ -0,0 +1,435 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_DIRECTORY_ENTRY_H
+#define _LIBCPP___FILESYSTEM_DIRECTORY_ENTRY_H
+
+#include <__chrono/time_point.h>
+#include <__compare/ordering.h>
+#include <__config>
+#include <__filesystem/file_status.h>
+#include <__filesystem/file_time_type.h>
+#include <__filesystem/file_type.h>
+#include <__filesystem/filesystem_error.h>
+#include <__filesystem/operations.h>
+#include <__filesystem/path.h>
+#include <__filesystem/perms.h>
+#include <__system_error/errc.h>
+#include <__system_error/error_code.h>
+#include <__utility/move.h>
+#include <__utility/unreachable.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH
+
+class directory_entry {
+ typedef filesystem::path _Path;
+
+public:
+ // constructors and destructors
+ _LIBCPP_HIDE_FROM_ABI directory_entry() noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI directory_entry(directory_entry const&) = default;
+ _LIBCPP_HIDE_FROM_ABI directory_entry(directory_entry&&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI explicit directory_entry(_Path const& __p) : __p_(__p) {
+ error_code __ec;
+ __refresh(&__ec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI directory_entry(_Path const& __p, error_code& __ec) : __p_(__p) { __refresh(&__ec); }
+
+ _LIBCPP_HIDE_FROM_ABI ~directory_entry() {}
+
+ _LIBCPP_HIDE_FROM_ABI directory_entry& operator=(directory_entry const&) = default;
+ _LIBCPP_HIDE_FROM_ABI directory_entry& operator=(directory_entry&&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI void assign(_Path const& __p) {
+ __p_ = __p;
+ error_code __ec;
+ __refresh(&__ec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void assign(_Path const& __p, error_code& __ec) {
+ __p_ = __p;
+ __refresh(&__ec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void replace_filename(_Path const& __p) {
+ __p_.replace_filename(__p);
+ error_code __ec;
+ __refresh(&__ec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void replace_filename(_Path const& __p, error_code& __ec) {
+ __p_ = __p_.parent_path() / __p;
+ __refresh(&__ec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void refresh() { __refresh(); }
+
+ _LIBCPP_HIDE_FROM_ABI void refresh(error_code& __ec) noexcept { __refresh(&__ec); }
+
+ _LIBCPP_HIDE_FROM_ABI _Path const& path() const noexcept { return __p_; }
+
+ _LIBCPP_HIDE_FROM_ABI operator const _Path&() const noexcept { return __p_; }
+
+ _LIBCPP_HIDE_FROM_ABI bool exists() const { return filesystem::exists(file_status{__get_ft()}); }
+
+ _LIBCPP_HIDE_FROM_ABI bool exists(error_code& __ec) const noexcept {
+ return filesystem::exists(file_status{__get_ft(&__ec)});
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_block_file() const { return __get_ft() == file_type::block; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_block_file(error_code& __ec) const noexcept {
+ return __get_ft(&__ec) == file_type::block;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_character_file() const { return __get_ft() == file_type::character; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_character_file(error_code& __ec) const noexcept {
+ return __get_ft(&__ec) == file_type::character;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_directory() const { return __get_ft() == file_type::directory; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_directory(error_code& __ec) const noexcept {
+ return __get_ft(&__ec) == file_type::directory;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_fifo() const { return __get_ft() == file_type::fifo; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_fifo(error_code& __ec) const noexcept { return __get_ft(&__ec) == file_type::fifo; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_other() const { return filesystem::is_other(file_status{__get_ft()}); }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_other(error_code& __ec) const noexcept {
+ return filesystem::is_other(file_status{__get_ft(&__ec)});
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_regular_file() const { return __get_ft() == file_type::regular; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_regular_file(error_code& __ec) const noexcept {
+ return __get_ft(&__ec) == file_type::regular;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_socket() const { return __get_ft() == file_type::socket; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_socket(error_code& __ec) const noexcept { return __get_ft(&__ec) == file_type::socket; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_symlink() const { return __get_sym_ft() == file_type::symlink; }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_symlink(error_code& __ec) const noexcept {
+ return __get_sym_ft(&__ec) == file_type::symlink;
+ }
+ _LIBCPP_HIDE_FROM_ABI uintmax_t file_size() const { return __get_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI uintmax_t file_size(error_code& __ec) const noexcept { return __get_size(&__ec); }
+
+ _LIBCPP_HIDE_FROM_ABI uintmax_t hard_link_count() const { return __get_nlink(); }
+
+ _LIBCPP_HIDE_FROM_ABI uintmax_t hard_link_count(error_code& __ec) const noexcept { return __get_nlink(&__ec); }
+
+ _LIBCPP_HIDE_FROM_ABI file_time_type last_write_time() const { return __get_write_time(); }
+
+ _LIBCPP_HIDE_FROM_ABI file_time_type last_write_time(error_code& __ec) const noexcept {
+ return __get_write_time(&__ec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI file_status status() const { return __get_status(); }
+
+ _LIBCPP_HIDE_FROM_ABI file_status status(error_code& __ec) const noexcept { return __get_status(&__ec); }
+
+ _LIBCPP_HIDE_FROM_ABI file_status symlink_status() const { return __get_symlink_status(); }
+
+ _LIBCPP_HIDE_FROM_ABI file_status symlink_status(error_code& __ec) const noexcept {
+ return __get_symlink_status(&__ec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool operator==(directory_entry const& __rhs) const noexcept { return __p_ == __rhs.__p_; }
+
+# if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(directory_entry const& __rhs) const noexcept { return __p_ != __rhs.__p_; }
+
+ _LIBCPP_HIDE_FROM_ABI bool operator<(directory_entry const& __rhs) const noexcept { return __p_ < __rhs.__p_; }
+
+ _LIBCPP_HIDE_FROM_ABI bool operator<=(directory_entry const& __rhs) const noexcept { return __p_ <= __rhs.__p_; }
+
+ _LIBCPP_HIDE_FROM_ABI bool operator>(directory_entry const& __rhs) const noexcept { return __p_ > __rhs.__p_; }
+
+ _LIBCPP_HIDE_FROM_ABI bool operator>=(directory_entry const& __rhs) const noexcept { return __p_ >= __rhs.__p_; }
+
+# else // _LIBCPP_STD_VER <= 17
+
+ _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(const directory_entry& __rhs) const noexcept {
+ return __p_ <=> __rhs.__p_;
+ }
+
+# endif // _LIBCPP_STD_VER <= 17
+
+ template <class _CharT, class _Traits>
+ _LIBCPP_HIDE_FROM_ABI friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const directory_entry& __d) {
+ return __os << __d.path();
+ }
+
+private:
+ friend class directory_iterator;
+ friend class recursive_directory_iterator;
+ friend class _LIBCPP_HIDDEN __dir_stream;
+
+ enum _CacheType : unsigned char {
+ _Empty,
+ _IterSymlink,
+ _IterNonSymlink,
+ _RefreshSymlink,
+ _RefreshSymlinkUnresolved,
+ _RefreshNonSymlink
+ };
+
+ struct __cached_data {
+ uintmax_t __size_;
+ uintmax_t __nlink_;
+ file_time_type __write_time_;
+ perms __sym_perms_;
+ perms __non_sym_perms_;
+ file_type __type_;
+ _CacheType __cache_type_;
+
+ _LIBCPP_HIDE_FROM_ABI __cached_data() noexcept { __reset(); }
+
+ _LIBCPP_HIDE_FROM_ABI void __reset() {
+ __cache_type_ = _Empty;
+ __type_ = file_type::none;
+ __sym_perms_ = __non_sym_perms_ = perms::unknown;
+ __size_ = __nlink_ = uintmax_t(-1);
+ __write_time_ = file_time_type::min();
+ }
+ };
+
+ _LIBCPP_HIDE_FROM_ABI static __cached_data __create_iter_result(file_type __ft) {
+ __cached_data __data;
+ __data.__type_ = __ft;
+ __data.__cache_type_ = [&]() {
+ switch (__ft) {
+ case file_type::none:
+ return _Empty;
+ case file_type::symlink:
+ return _IterSymlink;
+ default:
+ return _IterNonSymlink;
+ }
+ }();
+ return __data;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __assign_iter_entry(_Path&& __p, __cached_data __dt) {
+ __p_ = std::move(__p);
+ __data_ = __dt;
+ }
+
+ _LIBCPP_EXPORTED_FROM_ABI error_code __do_refresh() noexcept;
+
+ _LIBCPP_HIDE_FROM_ABI static bool __is_dne_error(error_code const& __ec) {
+ if (!__ec)
+ return true;
+ switch (static_cast<errc>(__ec.value())) {
+ case errc::no_such_file_or_directory:
+ case errc::not_a_directory:
+ return true;
+ default:
+ return false;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void
+ __handle_error(const char* __msg, error_code* __dest_ec, error_code const& __ec, bool __allow_dne = false) const {
+ if (__dest_ec) {
+ *__dest_ec = __ec;
+ return;
+ }
+ if (__ec && (!__allow_dne || !__is_dne_error(__ec)))
+ __throw_filesystem_error(__msg, __p_, __ec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __refresh(error_code* __ec = nullptr) {
+ __handle_error("in directory_entry::refresh",
+ __ec,
+ __do_refresh(),
+ /*allow_dne*/ true);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI file_type __get_sym_ft(error_code* __ec = nullptr) const {
+ switch (__data_.__cache_type_) {
+ case _Empty:
+ return __symlink_status(__p_, __ec).type();
+ case _IterSymlink:
+ case _RefreshSymlink:
+ case _RefreshSymlinkUnresolved:
+ if (__ec)
+ __ec->clear();
+ return file_type::symlink;
+ case _IterNonSymlink:
+ case _RefreshNonSymlink:
+ file_status __st(__data_.__type_);
+ if (__ec && !filesystem::exists(__st))
+ *__ec = make_error_code(errc::no_such_file_or_directory);
+ else if (__ec)
+ __ec->clear();
+ return __data_.__type_;
+ }
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI file_type __get_ft(error_code* __ec = nullptr) const {
+ switch (__data_.__cache_type_) {
+ case _Empty:
+ case _IterSymlink:
+ case _RefreshSymlinkUnresolved:
+ return __status(__p_, __ec).type();
+ case _IterNonSymlink:
+ case _RefreshNonSymlink:
+ case _RefreshSymlink: {
+ file_status __st(__data_.__type_);
+ if (__ec && !filesystem::exists(__st))
+ *__ec = make_error_code(errc::no_such_file_or_directory);
+ else if (__ec)
+ __ec->clear();
+ return __data_.__type_;
+ }
+ }
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI file_status __get_status(error_code* __ec = nullptr) const {
+ switch (__data_.__cache_type_) {
+ case _Empty:
+ case _IterNonSymlink:
+ case _IterSymlink:
+ case _RefreshSymlinkUnresolved:
+ return __status(__p_, __ec);
+ case _RefreshNonSymlink:
+ case _RefreshSymlink:
+ return file_status(__get_ft(__ec), __data_.__non_sym_perms_);
+ }
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI file_status __get_symlink_status(error_code* __ec = nullptr) const {
+ switch (__data_.__cache_type_) {
+ case _Empty:
+ case _IterNonSymlink:
+ case _IterSymlink:
+ return __symlink_status(__p_, __ec);
+ case _RefreshNonSymlink:
+ return file_status(__get_sym_ft(__ec), __data_.__non_sym_perms_);
+ case _RefreshSymlink:
+ case _RefreshSymlinkUnresolved:
+ return file_status(__get_sym_ft(__ec), __data_.__sym_perms_);
+ }
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI uintmax_t __get_size(error_code* __ec = nullptr) const {
+ switch (__data_.__cache_type_) {
+ case _Empty:
+ case _IterNonSymlink:
+ case _IterSymlink:
+ case _RefreshSymlinkUnresolved:
+ return filesystem::__file_size(__p_, __ec);
+ case _RefreshSymlink:
+ case _RefreshNonSymlink: {
+ error_code __m_ec;
+ file_status __st(__get_ft(&__m_ec));
+ __handle_error("in directory_entry::file_size", __ec, __m_ec);
+ if (filesystem::exists(__st) && !filesystem::is_regular_file(__st)) {
+ errc __err_kind = filesystem::is_directory(__st) ? errc::is_a_directory : errc::not_supported;
+ __handle_error("in directory_entry::file_size", __ec, make_error_code(__err_kind));
+ }
+ return __data_.__size_;
+ }
+ }
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI uintmax_t __get_nlink(error_code* __ec = nullptr) const {
+ switch (__data_.__cache_type_) {
+ case _Empty:
+ case _IterNonSymlink:
+ case _IterSymlink:
+ case _RefreshSymlinkUnresolved:
+ return filesystem::__hard_link_count(__p_, __ec);
+ case _RefreshSymlink:
+ case _RefreshNonSymlink: {
+ error_code __m_ec;
+ (void)__get_ft(&__m_ec);
+ __handle_error("in directory_entry::hard_link_count", __ec, __m_ec);
+ return __data_.__nlink_;
+ }
+ }
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI file_time_type __get_write_time(error_code* __ec = nullptr) const {
+ switch (__data_.__cache_type_) {
+ case _Empty:
+ case _IterNonSymlink:
+ case _IterSymlink:
+ case _RefreshSymlinkUnresolved:
+ return filesystem::__last_write_time(__p_, __ec);
+ case _RefreshSymlink:
+ case _RefreshNonSymlink: {
+ error_code __m_ec;
+ file_status __st(__get_ft(&__m_ec));
+ __handle_error("in directory_entry::last_write_time", __ec, __m_ec);
+ if (filesystem::exists(__st) && __data_.__write_time_ == file_time_type::min())
+ __handle_error("in directory_entry::last_write_time", __ec, make_error_code(errc::value_too_large));
+ return __data_.__write_time_;
+ }
+ }
+ __libcpp_unreachable();
+ }
+
+private:
+ _Path __p_;
+ __cached_data __data_;
+};
+
+class __dir_element_proxy {
+public:
+ inline _LIBCPP_HIDE_FROM_ABI directory_entry operator*() { return std::move(__elem_); }
+
+private:
+ friend class directory_iterator;
+ friend class recursive_directory_iterator;
+ _LIBCPP_HIDE_FROM_ABI explicit __dir_element_proxy(directory_entry const& __e) : __elem_(__e) {}
+ _LIBCPP_HIDE_FROM_ABI __dir_element_proxy(__dir_element_proxy&& __o) : __elem_(std::move(__o.__elem_)) {}
+ directory_entry __elem_;
+};
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FILESYSTEM_DIRECTORY_ENTRY_H
diff --git a/libcxx/include/__cxx03/__filesystem/directory_iterator.h b/libcxx/include/__cxx03/__filesystem/directory_iterator.h
new file mode 100644
index 00000000000000..e0246d8001e195
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/directory_iterator.h
@@ -0,0 +1,151 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_DIRECTORY_ITERATOR_H
+#define _LIBCPP___FILESYSTEM_DIRECTORY_ITERATOR_H
+
+#include <__assert>
+#include <__config>
+#include <__filesystem/directory_entry.h>
+#include <__filesystem/directory_options.h>
+#include <__filesystem/path.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/shared_ptr.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/enable_view.h>
+#include <__system_error/error_code.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH
+
+class _LIBCPP_HIDDEN __dir_stream;
+class directory_iterator {
+public:
+ typedef directory_entry value_type;
+ typedef ptrdiff_t difference_type;
+ typedef value_type const* pointer;
+ typedef value_type const& reference;
+ typedef input_iterator_tag iterator_category;
+
+public:
+ // ctor & dtor
+ _LIBCPP_HIDE_FROM_ABI directory_iterator() noexcept {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit directory_iterator(const path& __p) : directory_iterator(__p, nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI directory_iterator(const path& __p, directory_options __opts)
+ : directory_iterator(__p, nullptr, __opts) {}
+
+ _LIBCPP_HIDE_FROM_ABI directory_iterator(const path& __p, error_code& __ec) : directory_iterator(__p, &__ec) {}
+
+ _LIBCPP_HIDE_FROM_ABI directory_iterator(const path& __p, directory_options __opts, error_code& __ec)
+ : directory_iterator(__p, &__ec, __opts) {}
+
+ _LIBCPP_HIDE_FROM_ABI directory_iterator(const directory_iterator&) = default;
+ _LIBCPP_HIDE_FROM_ABI directory_iterator(directory_iterator&&) = default;
+ _LIBCPP_HIDE_FROM_ABI directory_iterator& operator=(const directory_iterator&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI directory_iterator& operator=(directory_iterator&& __o) noexcept {
+ // non-default implementation provided to support self-move assign.
+ if (this != &__o) {
+ __imp_ = std::move(__o.__imp_);
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~directory_iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI const directory_entry& operator*() const {
+ // Note: this check duplicates a check in `__dereference()`.
+ _LIBCPP_ASSERT_NON_NULL(__imp_, "The end iterator cannot be dereferenced");
+ return __dereference();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const directory_entry* operator->() const { return &**this; }
+
+ _LIBCPP_HIDE_FROM_ABI directory_iterator& operator++() { return __increment(); }
+
+ _LIBCPP_HIDE_FROM_ABI __dir_element_proxy operator++(int) {
+ __dir_element_proxy __p(**this);
+ __increment();
+ return __p;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI directory_iterator& increment(error_code& __ec) { return __increment(&__ec); }
+
+# if _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI bool operator==(default_sentinel_t) const noexcept { return *this == directory_iterator(); }
+
+# endif
+
+private:
+ inline _LIBCPP_HIDE_FROM_ABI friend bool
+ operator==(const directory_iterator& __lhs, const directory_iterator& __rhs) noexcept;
+
+ // construct the dir_stream
+ _LIBCPP_EXPORTED_FROM_ABI directory_iterator(const path&, error_code*, directory_options = directory_options::none);
+
+ _LIBCPP_EXPORTED_FROM_ABI directory_iterator& __increment(error_code* __ec = nullptr);
+
+ _LIBCPP_EXPORTED_FROM_ABI const directory_entry& __dereference() const;
+
+private:
+ shared_ptr<__dir_stream> __imp_;
+};
+
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const directory_iterator& __lhs, const directory_iterator& __rhs) noexcept {
+ return __lhs.__imp_ == __rhs.__imp_;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const directory_iterator& __lhs, const directory_iterator& __rhs) noexcept {
+ return !(__lhs == __rhs);
+}
+
+// enable directory_iterator range-based for statements
+inline _LIBCPP_HIDE_FROM_ABI directory_iterator begin(directory_iterator __iter) noexcept { return __iter; }
+
+inline _LIBCPP_HIDE_FROM_ABI directory_iterator end(directory_iterator) noexcept { return directory_iterator(); }
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+# if _LIBCPP_STD_VER >= 20
+
+template <>
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY inline constexpr bool
+ std::ranges::enable_borrowed_range<std::filesystem::directory_iterator> = true;
+
+template <>
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY inline constexpr bool
+ std::ranges::enable_view<std::filesystem::directory_iterator> = true;
+
+# endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FILESYSTEM_DIRECTORY_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__filesystem/directory_options.h b/libcxx/include/__cxx03/__filesystem/directory_options.h
new file mode 100644
index 00000000000000..d0cd3ebfdaa7ee
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/directory_options.h
@@ -0,0 +1,57 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_DIRECTORY_OPTIONS_H
+#define _LIBCPP___FILESYSTEM_DIRECTORY_OPTIONS_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+enum class directory_options : unsigned char { none = 0, follow_directory_symlink = 1, skip_permission_denied = 2 };
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr directory_options operator&(directory_options __lhs, directory_options __rhs) {
+ return static_cast<directory_options>(static_cast<unsigned char>(__lhs) & static_cast<unsigned char>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr directory_options operator|(directory_options __lhs, directory_options __rhs) {
+ return static_cast<directory_options>(static_cast<unsigned char>(__lhs) | static_cast<unsigned char>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr directory_options operator^(directory_options __lhs, directory_options __rhs) {
+ return static_cast<directory_options>(static_cast<unsigned char>(__lhs) ^ static_cast<unsigned char>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr directory_options operator~(directory_options __lhs) {
+ return static_cast<directory_options>(~static_cast<unsigned char>(__lhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline directory_options& operator&=(directory_options& __lhs, directory_options __rhs) {
+ return __lhs = __lhs & __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline directory_options& operator|=(directory_options& __lhs, directory_options __rhs) {
+ return __lhs = __lhs | __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline directory_options& operator^=(directory_options& __lhs, directory_options __rhs) {
+ return __lhs = __lhs ^ __rhs;
+}
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_DIRECTORY_OPTIONS_H
diff --git a/libcxx/include/__cxx03/__filesystem/file_status.h b/libcxx/include/__cxx03/__filesystem/file_status.h
new file mode 100644
index 00000000000000..da316c8b027464
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/file_status.h
@@ -0,0 +1,67 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_FILE_STATUS_H
+#define _LIBCPP___FILESYSTEM_FILE_STATUS_H
+
+#include <__config>
+#include <__filesystem/file_type.h>
+#include <__filesystem/perms.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+class _LIBCPP_EXPORTED_FROM_ABI file_status {
+public:
+ // constructors
+ _LIBCPP_HIDE_FROM_ABI file_status() noexcept : file_status(file_type::none) {}
+ _LIBCPP_HIDE_FROM_ABI explicit file_status(file_type __ft, perms __prms = perms::unknown) noexcept
+ : __ft_(__ft), __prms_(__prms) {}
+
+ _LIBCPP_HIDE_FROM_ABI file_status(const file_status&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI file_status(file_status&&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI ~file_status() {}
+
+ _LIBCPP_HIDE_FROM_ABI file_status& operator=(const file_status&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI file_status& operator=(file_status&&) noexcept = default;
+
+ // observers
+ _LIBCPP_HIDE_FROM_ABI file_type type() const noexcept { return __ft_; }
+
+ _LIBCPP_HIDE_FROM_ABI perms permissions() const noexcept { return __prms_; }
+
+ // modifiers
+ _LIBCPP_HIDE_FROM_ABI void type(file_type __ft) noexcept { __ft_ = __ft; }
+
+ _LIBCPP_HIDE_FROM_ABI void permissions(perms __p) noexcept { __prms_ = __p; }
+
+# if _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const file_status& __lhs, const file_status& __rhs) noexcept {
+ return __lhs.type() == __rhs.type() && __lhs.permissions() == __rhs.permissions();
+ }
+
+# endif
+
+private:
+ file_type __ft_;
+ perms __prms_;
+};
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_FILE_STATUS_H
diff --git a/libcxx/include/__cxx03/__filesystem/file_time_type.h b/libcxx/include/__cxx03/__filesystem/file_time_type.h
new file mode 100644
index 00000000000000..63e4ae1578cfd9
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/file_time_type.h
@@ -0,0 +1,31 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_FILE_TIME_TYPE_H
+#define _LIBCPP___FILESYSTEM_FILE_TIME_TYPE_H
+
+#include <__chrono/file_clock.h>
+#include <__chrono/time_point.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+typedef chrono::time_point<_FilesystemClock> file_time_type;
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_FILE_TIME_TYPE_H
diff --git a/libcxx/include/__cxx03/__filesystem/file_type.h b/libcxx/include/__cxx03/__filesystem/file_type.h
new file mode 100644
index 00000000000000..e4ac1dfee9ed9b
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/file_type.h
@@ -0,0 +1,42 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_FILE_TYPE_H
+#define _LIBCPP___FILESYSTEM_FILE_TYPE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+// On Windows, the library never identifies files as block, character, fifo
+// or socket.
+enum class file_type : signed char {
+ none = 0,
+ not_found = -1,
+ regular = 1,
+ directory = 2,
+ symlink = 3,
+ block = 4,
+ character = 5,
+ fifo = 6,
+ socket = 7,
+ unknown = 8
+};
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_FILE_TYPE_H
diff --git a/libcxx/include/__cxx03/__filesystem/filesystem_error.h b/libcxx/include/__cxx03/__filesystem/filesystem_error.h
new file mode 100644
index 00000000000000..80a11e3b1932c7
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/filesystem_error.h
@@ -0,0 +1,88 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_FILESYSTEM_ERROR_H
+#define _LIBCPP___FILESYSTEM_FILESYSTEM_ERROR_H
+
+#include <__config>
+#include <__filesystem/path.h>
+#include <__memory/shared_ptr.h>
+#include <__system_error/error_code.h>
+#include <__system_error/system_error.h>
+#include <__utility/forward.h>
+#include <__verbose_abort>
+#include <string>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+class _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_EXPORTED_FROM_ABI filesystem_error : public system_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI filesystem_error(const string& __what, error_code __ec)
+ : system_error(__ec, __what), __storage_(make_shared<_Storage>(path(), path())) {
+ __create_what(0);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI filesystem_error(const string& __what, const path& __p1, error_code __ec)
+ : system_error(__ec, __what), __storage_(make_shared<_Storage>(__p1, path())) {
+ __create_what(1);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI filesystem_error(const string& __what, const path& __p1, const path& __p2, error_code __ec)
+ : system_error(__ec, __what), __storage_(make_shared<_Storage>(__p1, __p2)) {
+ __create_what(2);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const path& path1() const noexcept { return __storage_->__p1_; }
+
+ _LIBCPP_HIDE_FROM_ABI const path& path2() const noexcept { return __storage_->__p2_; }
+
+ _LIBCPP_HIDE_FROM_ABI filesystem_error(const filesystem_error&) = default;
+ ~filesystem_error() override; // key function
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ const char* what() const noexcept override { return __storage_->__what_.c_str(); }
+
+ void __create_what(int __num_paths);
+
+private:
+ struct _LIBCPP_HIDDEN _Storage {
+ _LIBCPP_HIDE_FROM_ABI _Storage(const path& __p1, const path& __p2) : __p1_(__p1), __p2_(__p2) {}
+
+ path __p1_;
+ path __p2_;
+ string __what_;
+ };
+ shared_ptr<_Storage> __storage_;
+};
+
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+template <class... _Args>
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY void
+__throw_filesystem_error(_Args&&... __args) {
+ throw filesystem_error(std::forward<_Args>(__args)...);
+}
+# else
+template <class... _Args>
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY void
+__throw_filesystem_error(_Args&&...) {
+ _LIBCPP_VERBOSE_ABORT("filesystem_error was thrown in -fno-exceptions mode");
+}
+# endif
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_FILESYSTEM_ERROR_H
diff --git a/libcxx/include/__cxx03/__filesystem/operations.h b/libcxx/include/__cxx03/__filesystem/operations.h
new file mode 100644
index 00000000000000..f588189ed1d9de
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/operations.h
@@ -0,0 +1,310 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_OPERATIONS_H
+#define _LIBCPP___FILESYSTEM_OPERATIONS_H
+
+#include <__chrono/time_point.h>
+#include <__config>
+#include <__filesystem/copy_options.h>
+#include <__filesystem/file_status.h>
+#include <__filesystem/file_time_type.h>
+#include <__filesystem/file_type.h>
+#include <__filesystem/path.h>
+#include <__filesystem/perm_options.h>
+#include <__filesystem/perms.h>
+#include <__filesystem/space_info.h>
+#include <__system_error/error_code.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH
+
+_LIBCPP_EXPORTED_FROM_ABI path __absolute(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI path __canonical(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI bool
+__copy_file(const path& __from, const path& __to, copy_options __opt, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void
+__copy_symlink(const path& __existing_symlink, const path& __new_symlink, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void
+__copy(const path& __from, const path& __to, copy_options __opt, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI bool __create_directories(const path&, error_code* = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void
+__create_directory_symlink(const path& __to, const path& __new_symlink, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI bool __create_directory(const path&, error_code* = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI bool __create_directory(const path&, const path& __attributes, error_code* = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void
+__create_hard_link(const path& __to, const path& __new_hard_link, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void
+__create_symlink(const path& __to, const path& __new_symlink, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI path __current_path(error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void __current_path(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI bool __equivalent(const path&, const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI file_status __status(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI uintmax_t __file_size(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI uintmax_t __hard_link_count(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI file_status __symlink_status(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI file_time_type __last_write_time(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void __last_write_time(const path&, file_time_type __new_time, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI path __weakly_canonical(path const& __p, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI path __read_symlink(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI uintmax_t __remove_all(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI bool __remove(const path&, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void __rename(const path& __from, const path& __to, error_code* __ec = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI void __resize_file(const path&, uintmax_t __size, error_code* = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI path __temp_directory_path(error_code* __ec = nullptr);
+
+inline _LIBCPP_HIDE_FROM_ABI path absolute(const path& __p) { return __absolute(__p); }
+inline _LIBCPP_HIDE_FROM_ABI path absolute(const path& __p, error_code& __ec) { return __absolute(__p, &__ec); }
+inline _LIBCPP_HIDE_FROM_ABI path canonical(const path& __p) { return __canonical(__p); }
+inline _LIBCPP_HIDE_FROM_ABI path canonical(const path& __p, error_code& __ec) { return __canonical(__p, &__ec); }
+inline _LIBCPP_HIDE_FROM_ABI bool copy_file(const path& __from, const path& __to) {
+ return __copy_file(__from, __to, copy_options::none);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool copy_file(const path& __from, const path& __to, error_code& __ec) {
+ return __copy_file(__from, __to, copy_options::none, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool copy_file(const path& __from, const path& __to, copy_options __opt) {
+ return __copy_file(__from, __to, __opt);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool
+copy_file(const path& __from, const path& __to, copy_options __opt, error_code& __ec) {
+ return __copy_file(__from, __to, __opt, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void copy_symlink(const path& __from, const path& __to) { __copy_symlink(__from, __to); }
+inline _LIBCPP_HIDE_FROM_ABI void copy_symlink(const path& __from, const path& __to, error_code& __ec) noexcept {
+ __copy_symlink(__from, __to, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void copy(const path& __from, const path& __to) {
+ __copy(__from, __to, copy_options::none);
+}
+inline _LIBCPP_HIDE_FROM_ABI void copy(const path& __from, const path& __to, error_code& __ec) {
+ __copy(__from, __to, copy_options::none, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void copy(const path& __from, const path& __to, copy_options __opt) {
+ __copy(__from, __to, __opt);
+}
+inline _LIBCPP_HIDE_FROM_ABI void copy(const path& __from, const path& __to, copy_options __opt, error_code& __ec) {
+ __copy(__from, __to, __opt, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool create_directories(const path& __p) { return __create_directories(__p); }
+inline _LIBCPP_HIDE_FROM_ABI bool create_directories(const path& __p, error_code& __ec) {
+ return __create_directories(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void create_directory_symlink(const path& __target, const path& __link) {
+ __create_directory_symlink(__target, __link);
+}
+inline _LIBCPP_HIDE_FROM_ABI void
+create_directory_symlink(const path& __target, const path& __link, error_code& __ec) noexcept {
+ __create_directory_symlink(__target, __link, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool create_directory(const path& __p) { return __create_directory(__p); }
+inline _LIBCPP_HIDE_FROM_ABI bool create_directory(const path& __p, error_code& __ec) noexcept {
+ return __create_directory(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool create_directory(const path& __p, const path& __attrs) {
+ return __create_directory(__p, __attrs);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool create_directory(const path& __p, const path& __attrs, error_code& __ec) noexcept {
+ return __create_directory(__p, __attrs, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void create_hard_link(const path& __target, const path& __link) {
+ __create_hard_link(__target, __link);
+}
+inline _LIBCPP_HIDE_FROM_ABI void
+create_hard_link(const path& __target, const path& __link, error_code& __ec) noexcept {
+ __create_hard_link(__target, __link, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void create_symlink(const path& __target, const path& __link) {
+ __create_symlink(__target, __link);
+}
+inline _LIBCPP_HIDE_FROM_ABI void create_symlink(const path& __target, const path& __link, error_code& __ec) noexcept {
+ return __create_symlink(__target, __link, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI path current_path() { return __current_path(); }
+inline _LIBCPP_HIDE_FROM_ABI path current_path(error_code& __ec) { return __current_path(&__ec); }
+inline _LIBCPP_HIDE_FROM_ABI void current_path(const path& __p) { __current_path(__p); }
+inline _LIBCPP_HIDE_FROM_ABI void current_path(const path& __p, error_code& __ec) noexcept {
+ __current_path(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool equivalent(const path& __p1, const path& __p2) { return __equivalent(__p1, __p2); }
+inline _LIBCPP_HIDE_FROM_ABI bool equivalent(const path& __p1, const path& __p2, error_code& __ec) noexcept {
+ return __equivalent(__p1, __p2, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool status_known(file_status __s) noexcept { return __s.type() != file_type::none; }
+inline _LIBCPP_HIDE_FROM_ABI bool exists(file_status __s) noexcept {
+ return status_known(__s) && __s.type() != file_type::not_found;
+}
+inline _LIBCPP_HIDE_FROM_ABI bool exists(const path& __p) { return exists(__status(__p)); }
+
+inline _LIBCPP_HIDE_FROM_ABI bool exists(const path& __p, error_code& __ec) noexcept {
+ auto __s = __status(__p, &__ec);
+ if (status_known(__s))
+ __ec.clear();
+ return exists(__s);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI uintmax_t file_size(const path& __p) { return __file_size(__p); }
+inline _LIBCPP_HIDE_FROM_ABI uintmax_t file_size(const path& __p, error_code& __ec) noexcept {
+ return __file_size(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI uintmax_t hard_link_count(const path& __p) { return __hard_link_count(__p); }
+inline _LIBCPP_HIDE_FROM_ABI uintmax_t hard_link_count(const path& __p, error_code& __ec) noexcept {
+ return __hard_link_count(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_block_file(file_status __s) noexcept { return __s.type() == file_type::block; }
+inline _LIBCPP_HIDE_FROM_ABI bool is_block_file(const path& __p) { return is_block_file(__status(__p)); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_block_file(const path& __p, error_code& __ec) noexcept {
+ return is_block_file(__status(__p, &__ec));
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_character_file(file_status __s) noexcept {
+ return __s.type() == file_type::character;
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_character_file(const path& __p) { return is_character_file(__status(__p)); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_character_file(const path& __p, error_code& __ec) noexcept {
+ return is_character_file(__status(__p, &__ec));
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_directory(file_status __s) noexcept { return __s.type() == file_type::directory; }
+inline _LIBCPP_HIDE_FROM_ABI bool is_directory(const path& __p) { return is_directory(__status(__p)); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_directory(const path& __p, error_code& __ec) noexcept {
+ return is_directory(__status(__p, &__ec));
+}
+_LIBCPP_EXPORTED_FROM_ABI bool __fs_is_empty(const path& __p, error_code* __ec = nullptr);
+inline _LIBCPP_HIDE_FROM_ABI bool is_empty(const path& __p) { return __fs_is_empty(__p); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_empty(const path& __p, error_code& __ec) { return __fs_is_empty(__p, &__ec); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_fifo(file_status __s) noexcept { return __s.type() == file_type::fifo; }
+inline _LIBCPP_HIDE_FROM_ABI bool is_fifo(const path& __p) { return is_fifo(__status(__p)); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_fifo(const path& __p, error_code& __ec) noexcept {
+ return is_fifo(__status(__p, &__ec));
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_regular_file(file_status __s) noexcept { return __s.type() == file_type::regular; }
+inline _LIBCPP_HIDE_FROM_ABI bool is_regular_file(const path& __p) { return is_regular_file(__status(__p)); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_regular_file(const path& __p, error_code& __ec) noexcept {
+ return is_regular_file(__status(__p, &__ec));
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_symlink(file_status __s) noexcept { return __s.type() == file_type::symlink; }
+inline _LIBCPP_HIDE_FROM_ABI bool is_symlink(const path& __p) { return is_symlink(__symlink_status(__p)); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_symlink(const path& __p, error_code& __ec) noexcept {
+ return is_symlink(__symlink_status(__p, &__ec));
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_other(file_status __s) noexcept {
+ return exists(__s) && !is_regular_file(__s) && !is_directory(__s) && !is_symlink(__s);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_other(const path& __p) { return is_other(__status(__p)); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_other(const path& __p, error_code& __ec) noexcept {
+ return is_other(__status(__p, &__ec));
+}
+inline _LIBCPP_HIDE_FROM_ABI bool is_socket(file_status __s) noexcept { return __s.type() == file_type::socket; }
+inline _LIBCPP_HIDE_FROM_ABI bool is_socket(const path& __p) { return is_socket(__status(__p)); }
+inline _LIBCPP_HIDE_FROM_ABI bool is_socket(const path& __p, error_code& __ec) noexcept {
+ return is_socket(__status(__p, &__ec));
+}
+inline _LIBCPP_HIDE_FROM_ABI file_time_type last_write_time(const path& __p) { return __last_write_time(__p); }
+inline _LIBCPP_HIDE_FROM_ABI file_time_type last_write_time(const path& __p, error_code& __ec) noexcept {
+ return __last_write_time(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void last_write_time(const path& __p, file_time_type __t) { __last_write_time(__p, __t); }
+inline _LIBCPP_HIDE_FROM_ABI void last_write_time(const path& __p, file_time_type __t, error_code& __ec) noexcept {
+ __last_write_time(__p, __t, &__ec);
+}
+_LIBCPP_EXPORTED_FROM_ABI void __permissions(const path&, perms, perm_options, error_code* = nullptr);
+inline _LIBCPP_HIDE_FROM_ABI void
+permissions(const path& __p, perms __prms, perm_options __opts = perm_options::replace) {
+ __permissions(__p, __prms, __opts);
+}
+inline _LIBCPP_HIDE_FROM_ABI void permissions(const path& __p, perms __prms, error_code& __ec) noexcept {
+ __permissions(__p, __prms, perm_options::replace, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void permissions(const path& __p, perms __prms, perm_options __opts, error_code& __ec) {
+ __permissions(__p, __prms, __opts, &__ec);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI path proximate(const path& __p, const path& __base, error_code& __ec) {
+ path __tmp = __weakly_canonical(__p, &__ec);
+ if (__ec)
+ return {};
+ path __tmp_base = __weakly_canonical(__base, &__ec);
+ if (__ec)
+ return {};
+ return __tmp.lexically_proximate(__tmp_base);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI path proximate(const path& __p, error_code& __ec) {
+ return proximate(__p, current_path(), __ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI path proximate(const path& __p, const path& __base = current_path()) {
+ return __weakly_canonical(__p).lexically_proximate(__weakly_canonical(__base));
+}
+inline _LIBCPP_HIDE_FROM_ABI path read_symlink(const path& __p) { return __read_symlink(__p); }
+inline _LIBCPP_HIDE_FROM_ABI path read_symlink(const path& __p, error_code& __ec) { return __read_symlink(__p, &__ec); }
+
+inline _LIBCPP_HIDE_FROM_ABI path relative(const path& __p, const path& __base, error_code& __ec) {
+ path __tmp = __weakly_canonical(__p, &__ec);
+ if (__ec)
+ return path();
+ path __tmpbase = __weakly_canonical(__base, &__ec);
+ if (__ec)
+ return path();
+ return __tmp.lexically_relative(__tmpbase);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI path relative(const path& __p, error_code& __ec) {
+ return relative(__p, current_path(), __ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI path relative(const path& __p, const path& __base = current_path()) {
+ return __weakly_canonical(__p).lexically_relative(__weakly_canonical(__base));
+}
+inline _LIBCPP_HIDE_FROM_ABI uintmax_t remove_all(const path& __p) { return __remove_all(__p); }
+inline _LIBCPP_HIDE_FROM_ABI uintmax_t remove_all(const path& __p, error_code& __ec) {
+ return __remove_all(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI bool remove(const path& __p) { return __remove(__p); }
+inline _LIBCPP_HIDE_FROM_ABI bool remove(const path& __p, error_code& __ec) noexcept { return __remove(__p, &__ec); }
+inline _LIBCPP_HIDE_FROM_ABI void rename(const path& __from, const path& __to) { return __rename(__from, __to); }
+inline _LIBCPP_HIDE_FROM_ABI void rename(const path& __from, const path& __to, error_code& __ec) noexcept {
+ return __rename(__from, __to, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI void resize_file(const path& __p, uintmax_t __ns) { return __resize_file(__p, __ns); }
+inline _LIBCPP_HIDE_FROM_ABI void resize_file(const path& __p, uintmax_t __ns, error_code& __ec) noexcept {
+ return __resize_file(__p, __ns, &__ec);
+}
+_LIBCPP_EXPORTED_FROM_ABI space_info __space(const path&, error_code* __ec = nullptr);
+inline _LIBCPP_HIDE_FROM_ABI space_info space(const path& __p) { return __space(__p); }
+inline _LIBCPP_HIDE_FROM_ABI space_info space(const path& __p, error_code& __ec) noexcept {
+ return __space(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI file_status status(const path& __p) { return __status(__p); }
+inline _LIBCPP_HIDE_FROM_ABI file_status status(const path& __p, error_code& __ec) noexcept {
+ return __status(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI file_status symlink_status(const path& __p) { return __symlink_status(__p); }
+inline _LIBCPP_HIDE_FROM_ABI file_status symlink_status(const path& __p, error_code& __ec) noexcept {
+ return __symlink_status(__p, &__ec);
+}
+inline _LIBCPP_HIDE_FROM_ABI path temp_directory_path() { return __temp_directory_path(); }
+inline _LIBCPP_HIDE_FROM_ABI path temp_directory_path(error_code& __ec) { return __temp_directory_path(&__ec); }
+inline _LIBCPP_HIDE_FROM_ABI path weakly_canonical(path const& __p) { return __weakly_canonical(__p); }
+inline _LIBCPP_HIDE_FROM_ABI path weakly_canonical(path const& __p, error_code& __ec) {
+ return __weakly_canonical(__p, &__ec);
+}
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+#endif // _LIBCPP___FILESYSTEM_OPERATIONS_H
diff --git a/libcxx/include/__cxx03/__filesystem/path.h b/libcxx/include/__cxx03/__filesystem/path.h
new file mode 100644
index 00000000000000..ff468d517722fe
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/path.h
@@ -0,0 +1,931 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_PATH_H
+#define _LIBCPP___FILESYSTEM_PATH_H
+
+#include <__algorithm/replace.h>
+#include <__algorithm/replace_copy.h>
+#include <__config>
+#include <__functional/unary_function.h>
+#include <__fwd/functional.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_pointer.h>
+#include <cstddef>
+#include <string>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <iomanip> // for quoted
+# include <locale>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH
+
+template <class _Tp>
+struct __can_convert_char {
+ static const bool value = false;
+};
+template <class _Tp>
+struct __can_convert_char<const _Tp> : public __can_convert_char<_Tp> {};
+template <>
+struct __can_convert_char<char> {
+ static const bool value = true;
+ using __char_type = char;
+};
+template <>
+struct __can_convert_char<wchar_t> {
+ static const bool value = true;
+ using __char_type = wchar_t;
+};
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <>
+struct __can_convert_char<char8_t> {
+ static const bool value = true;
+ using __char_type = char8_t;
+};
+# endif
+template <>
+struct __can_convert_char<char16_t> {
+ static const bool value = true;
+ using __char_type = char16_t;
+};
+template <>
+struct __can_convert_char<char32_t> {
+ static const bool value = true;
+ using __char_type = char32_t;
+};
+
+template <class _ECharT, __enable_if_t<__can_convert_char<_ECharT>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI bool __is_separator(_ECharT __e) {
+# if defined(_LIBCPP_WIN32API)
+ return __e == _ECharT('/') || __e == _ECharT('\\');
+# else
+ return __e == _ECharT('/');
+# endif
+}
+
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+typedef u8string __u8_string;
+# else
+typedef string __u8_string;
+# endif
+
+struct _NullSentinel {};
+
+template <class _Tp>
+using _Void = void;
+
+template <class _Tp, class = void>
+struct __is_pathable_string : public false_type {};
+
+template <class _ECharT, class _Traits, class _Alloc>
+struct __is_pathable_string< basic_string<_ECharT, _Traits, _Alloc>,
+ _Void<typename __can_convert_char<_ECharT>::__char_type> >
+ : public __can_convert_char<_ECharT> {
+ using _Str = basic_string<_ECharT, _Traits, _Alloc>;
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT const* __range_begin(_Str const& __s) { return __s.data(); }
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT const* __range_end(_Str const& __s) { return __s.data() + __s.length(); }
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT __first_or_null(_Str const& __s) { return __s.empty() ? _ECharT{} : __s[0]; }
+};
+
+template <class _ECharT, class _Traits>
+struct __is_pathable_string< basic_string_view<_ECharT, _Traits>,
+ _Void<typename __can_convert_char<_ECharT>::__char_type> >
+ : public __can_convert_char<_ECharT> {
+ using _Str = basic_string_view<_ECharT, _Traits>;
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT const* __range_begin(_Str const& __s) { return __s.data(); }
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT const* __range_end(_Str const& __s) { return __s.data() + __s.length(); }
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT __first_or_null(_Str const& __s) { return __s.empty() ? _ECharT{} : __s[0]; }
+};
+
+template <class _Source,
+ class _DS = __decay_t<_Source>,
+ class _UnqualPtrType = __remove_const_t<__remove_pointer_t<_DS> >,
+ bool _IsCharPtr = is_pointer<_DS>::value && __can_convert_char<_UnqualPtrType>::value>
+struct __is_pathable_char_array : false_type {};
+
+template <class _Source, class _ECharT, class _UPtr>
+struct __is_pathable_char_array<_Source, _ECharT*, _UPtr, true> : __can_convert_char<__remove_const_t<_ECharT> > {
+ _LIBCPP_HIDE_FROM_ABI static _ECharT const* __range_begin(const _ECharT* __b) { return __b; }
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT const* __range_end(const _ECharT* __b) {
+ using _Iter = const _ECharT*;
+ const _ECharT __sentinel = _ECharT{};
+ _Iter __e = __b;
+ for (; *__e != __sentinel; ++__e)
+ ;
+ return __e;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT __first_or_null(const _ECharT* __b) { return *__b; }
+};
+
+template <class _Iter, bool _IsIt = __has_input_iterator_category<_Iter>::value, class = void>
+struct __is_pathable_iter : false_type {};
+
+template <class _Iter>
+struct __is_pathable_iter<
+ _Iter,
+ true,
+ _Void<typename __can_convert_char< typename iterator_traits<_Iter>::value_type>::__char_type> >
+ : __can_convert_char<typename iterator_traits<_Iter>::value_type> {
+ using _ECharT = typename iterator_traits<_Iter>::value_type;
+
+ _LIBCPP_HIDE_FROM_ABI static _Iter __range_begin(_Iter __b) { return __b; }
+
+ _LIBCPP_HIDE_FROM_ABI static _NullSentinel __range_end(_Iter) { return _NullSentinel{}; }
+
+ _LIBCPP_HIDE_FROM_ABI static _ECharT __first_or_null(_Iter __b) { return *__b; }
+};
+
+template <class _Tp,
+ bool _IsStringT = __is_pathable_string<_Tp>::value,
+ bool _IsCharIterT = __is_pathable_char_array<_Tp>::value,
+ bool _IsIterT = !_IsCharIterT && __is_pathable_iter<_Tp>::value>
+struct __is_pathable : false_type {
+ static_assert(!_IsStringT && !_IsCharIterT && !_IsIterT, "Must all be false");
+};
+
+template <class _Tp>
+struct __is_pathable<_Tp, true, false, false> : __is_pathable_string<_Tp> {};
+
+template <class _Tp>
+struct __is_pathable<_Tp, false, true, false> : __is_pathable_char_array<_Tp> {};
+
+template <class _Tp>
+struct __is_pathable<_Tp, false, false, true> : __is_pathable_iter<_Tp> {};
+
+# if defined(_LIBCPP_WIN32API)
+typedef wstring __path_string;
+typedef wchar_t __path_value;
+# else
+typedef string __path_string;
+typedef char __path_value;
+# endif
+
+# if defined(_LIBCPP_WIN32API)
+_LIBCPP_EXPORTED_FROM_ABI size_t __wide_to_char(const wstring&, char*, size_t);
+_LIBCPP_EXPORTED_FROM_ABI size_t __char_to_wide(const string&, wchar_t*, size_t);
+# endif
+
+template <class _ECharT>
+struct _PathCVT;
+
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+template <class _ECharT>
+struct _PathCVT {
+ static_assert(__can_convert_char<_ECharT>::value, "Char type not convertible");
+
+ typedef __narrow_to_utf8<sizeof(_ECharT) * __CHAR_BIT__> _Narrower;
+# if defined(_LIBCPP_WIN32API)
+ typedef __widen_from_utf8<sizeof(wchar_t) * __CHAR_BIT__> _Widener;
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _ECharT const* __b, _ECharT const* __e) {
+# if defined(_LIBCPP_WIN32API)
+ string __utf8;
+ _Narrower()(back_inserter(__utf8), __b, __e);
+ _Widener()(back_inserter(__dest), __utf8.data(), __utf8.data() + __utf8.size());
+# else
+ _Narrower()(back_inserter(__dest), __b, __e);
+# endif
+ }
+
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
+ static_assert(!is_same<_Iter, _ECharT*>::value, "Call const overload");
+ if (__b == __e)
+ return;
+ basic_string<_ECharT> __tmp(__b, __e);
+# if defined(_LIBCPP_WIN32API)
+ string __utf8;
+ _Narrower()(back_inserter(__utf8), __tmp.data(), __tmp.data() + __tmp.length());
+ _Widener()(back_inserter(__dest), __utf8.data(), __utf8.data() + __utf8.size());
+# else
+ _Narrower()(back_inserter(__dest), __tmp.data(), __tmp.data() + __tmp.length());
+# endif
+ }
+
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _NullSentinel) {
+ static_assert(!is_same<_Iter, _ECharT*>::value, "Call const overload");
+ const _ECharT __sentinel = _ECharT{};
+ if (*__b == __sentinel)
+ return;
+ basic_string<_ECharT> __tmp;
+ for (; *__b != __sentinel; ++__b)
+ __tmp.push_back(*__b);
+# if defined(_LIBCPP_WIN32API)
+ string __utf8;
+ _Narrower()(back_inserter(__utf8), __tmp.data(), __tmp.data() + __tmp.length());
+ _Widener()(back_inserter(__dest), __utf8.data(), __utf8.data() + __utf8.size());
+# else
+ _Narrower()(back_inserter(__dest), __tmp.data(), __tmp.data() + __tmp.length());
+# endif
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI static void __append_source(__path_string& __dest, _Source const& __s) {
+ using _Traits = __is_pathable<_Source>;
+ __append_range(__dest, _Traits::__range_begin(__s), _Traits::__range_end(__s));
+ }
+};
+# endif // !_LIBCPP_HAS_NO_LOCALIZATION
+
+template <>
+struct _PathCVT<__path_value> {
+ template <class _Iter, __enable_if_t<__has_exactly_input_iterator_category<_Iter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
+ for (; __b != __e; ++__b)
+ __dest.push_back(*__b);
+ }
+
+ template <class _Iter, __enable_if_t<__has_forward_iterator_category<_Iter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
+ __dest.append(__b, __e);
+ }
+
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _NullSentinel) {
+ const char __sentinel = char{};
+ for (; *__b != __sentinel; ++__b)
+ __dest.push_back(*__b);
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI static void __append_source(__path_string& __dest, _Source const& __s) {
+ using _Traits = __is_pathable<_Source>;
+ __append_range(__dest, _Traits::__range_begin(__s), _Traits::__range_end(__s));
+ }
+};
+
+# if defined(_LIBCPP_WIN32API)
+template <>
+struct _PathCVT<char> {
+ _LIBCPP_HIDE_FROM_ABI static void __append_string(__path_string& __dest, const basic_string<char>& __str) {
+ size_t __size = __char_to_wide(__str, nullptr, 0);
+ size_t __pos = __dest.size();
+ __dest.resize(__pos + __size);
+ __char_to_wide(__str, const_cast<__path_value*>(__dest.data()) + __pos, __size);
+ }
+
+ template <class _Iter, __enable_if_t<__has_exactly_input_iterator_category<_Iter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
+ basic_string<char> __tmp(__b, __e);
+ __append_string(__dest, __tmp);
+ }
+
+ template <class _Iter, __enable_if_t<__has_forward_iterator_category<_Iter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
+ basic_string<char> __tmp(__b, __e);
+ __append_string(__dest, __tmp);
+ }
+
+ template <class _Iter>
+ _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _NullSentinel) {
+ const char __sentinel = char{};
+ basic_string<char> __tmp;
+ for (; *__b != __sentinel; ++__b)
+ __tmp.push_back(*__b);
+ __append_string(__dest, __tmp);
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI static void __append_source(__path_string& __dest, _Source const& __s) {
+ using _Traits = __is_pathable<_Source>;
+ __append_range(__dest, _Traits::__range_begin(__s), _Traits::__range_end(__s));
+ }
+};
+
+template <class _ECharT>
+struct _PathExport {
+ typedef __narrow_to_utf8<sizeof(wchar_t) * __CHAR_BIT__> _Narrower;
+ typedef __widen_from_utf8<sizeof(_ECharT) * __CHAR_BIT__> _Widener;
+
+ template <class _Str>
+ _LIBCPP_HIDE_FROM_ABI static void __append(_Str& __dest, const __path_string& __src) {
+ string __utf8;
+ _Narrower()(back_inserter(__utf8), __src.data(), __src.data() + __src.size());
+ _Widener()(back_inserter(__dest), __utf8.data(), __utf8.data() + __utf8.size());
+ }
+};
+
+template <>
+struct _PathExport<char> {
+ template <class _Str>
+ _LIBCPP_HIDE_FROM_ABI static void __append(_Str& __dest, const __path_string& __src) {
+ size_t __size = __wide_to_char(__src, nullptr, 0);
+ size_t __pos = __dest.size();
+ __dest.resize(__size);
+ __wide_to_char(__src, const_cast<char*>(__dest.data()) + __pos, __size);
+ }
+};
+
+template <>
+struct _PathExport<wchar_t> {
+ template <class _Str>
+ _LIBCPP_HIDE_FROM_ABI static void __append(_Str& __dest, const __path_string& __src) {
+ __dest.append(__src.begin(), __src.end());
+ }
+};
+
+template <>
+struct _PathExport<char16_t> {
+ template <class _Str>
+ _LIBCPP_HIDE_FROM_ABI static void __append(_Str& __dest, const __path_string& __src) {
+ __dest.append(__src.begin(), __src.end());
+ }
+};
+
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <>
+struct _PathExport<char8_t> {
+ typedef __narrow_to_utf8<sizeof(wchar_t) * __CHAR_BIT__> _Narrower;
+
+ template <class _Str>
+ _LIBCPP_HIDE_FROM_ABI static void __append(_Str& __dest, const __path_string& __src) {
+ _Narrower()(back_inserter(__dest), __src.data(), __src.data() + __src.size());
+ }
+};
+# endif /* !_LIBCPP_HAS_NO_CHAR8_T */
+# endif /* _LIBCPP_WIN32API */
+
+class _LIBCPP_EXPORTED_FROM_ABI path {
+ template <class _SourceOrIter, class _Tp = path&>
+ using _EnableIfPathable = __enable_if_t<__is_pathable<_SourceOrIter>::value, _Tp>;
+
+ template <class _Tp>
+ using _SourceChar = typename __is_pathable<_Tp>::__char_type;
+
+ template <class _Tp>
+ using _SourceCVT = _PathCVT<_SourceChar<_Tp> >;
+
+public:
+# if defined(_LIBCPP_WIN32API)
+ typedef wchar_t value_type;
+ static constexpr value_type preferred_separator = L'\\';
+# else
+ typedef char value_type;
+ static constexpr value_type preferred_separator = '/';
+# endif
+ typedef basic_string<value_type> string_type;
+ typedef basic_string_view<value_type> __string_view;
+
+ enum format : unsigned char { auto_format, native_format, generic_format };
+
+ // constructors and destructor
+ _LIBCPP_HIDE_FROM_ABI path() noexcept {}
+ _LIBCPP_HIDE_FROM_ABI path(const path& __p) : __pn_(__p.__pn_) {}
+ _LIBCPP_HIDE_FROM_ABI path(path&& __p) noexcept : __pn_(std::move(__p.__pn_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI path(string_type&& __s, format = format::auto_format) noexcept : __pn_(std::move(__s)) {}
+
+ template <class _Source, class = _EnableIfPathable<_Source, void> >
+ _LIBCPP_HIDE_FROM_ABI path(const _Source& __src, format = format::auto_format) {
+ _SourceCVT<_Source>::__append_source(__pn_, __src);
+ }
+
+ template <class _InputIt>
+ _LIBCPP_HIDE_FROM_ABI path(_InputIt __first, _InputIt __last, format = format::auto_format) {
+ typedef typename iterator_traits<_InputIt>::value_type _ItVal;
+ _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
+ }
+
+ /*
+ #if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ // TODO Implement locale conversions.
+ template <class _Source, class = _EnableIfPathable<_Source, void> >
+ path(const _Source& __src, const locale& __loc, format = format::auto_format);
+ template <class _InputIt>
+ path(_InputIt __first, _InputIt _last, const locale& __loc,
+ format = format::auto_format);
+ #endif
+ */
+
+ _LIBCPP_HIDE_FROM_ABI ~path() = default;
+
+ // assignments
+ _LIBCPP_HIDE_FROM_ABI path& operator=(const path& __p) {
+ __pn_ = __p.__pn_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& operator=(path&& __p) noexcept {
+ __pn_ = std::move(__p.__pn_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& operator=(string_type&& __s) noexcept {
+ __pn_ = std::move(__s);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& assign(string_type&& __s) noexcept {
+ __pn_ = std::move(__s);
+ return *this;
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI _EnableIfPathable<_Source> operator=(const _Source& __src) {
+ return this->assign(__src);
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI _EnableIfPathable<_Source> assign(const _Source& __src) {
+ __pn_.clear();
+ _SourceCVT<_Source>::__append_source(__pn_, __src);
+ return *this;
+ }
+
+ template <class _InputIt>
+ _LIBCPP_HIDE_FROM_ABI path& assign(_InputIt __first, _InputIt __last) {
+ typedef typename iterator_traits<_InputIt>::value_type _ItVal;
+ __pn_.clear();
+ _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
+ return *this;
+ }
+
+public:
+ // appends
+# if defined(_LIBCPP_WIN32API)
+ _LIBCPP_HIDE_FROM_ABI path& operator/=(const path& __p) {
+ auto __p_root_name = __p.__root_name();
+ auto __p_root_name_size = __p_root_name.size();
+ if (__p.is_absolute() || (!__p_root_name.empty() && __p_root_name != __string_view(root_name().__pn_))) {
+ __pn_ = __p.__pn_;
+ return *this;
+ }
+ if (__p.has_root_directory()) {
+ path __root_name_str = root_name();
+ __pn_ = __root_name_str.native();
+ __pn_ += __string_view(__p.__pn_).substr(__p_root_name_size);
+ return *this;
+ }
+ if (has_filename() || (!has_root_directory() && is_absolute()))
+ __pn_ += preferred_separator;
+ __pn_ += __string_view(__p.__pn_).substr(__p_root_name_size);
+ return *this;
+ }
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI _EnableIfPathable<_Source> operator/=(const _Source& __src) {
+ return operator/=(path(__src));
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI _EnableIfPathable<_Source> append(const _Source& __src) {
+ return operator/=(path(__src));
+ }
+
+ template <class _InputIt>
+ _LIBCPP_HIDE_FROM_ABI path& append(_InputIt __first, _InputIt __last) {
+ return operator/=(path(__first, __last));
+ }
+# else
+ _LIBCPP_HIDE_FROM_ABI path& operator/=(const path& __p) {
+ if (__p.is_absolute()) {
+ __pn_ = __p.__pn_;
+ return *this;
+ }
+ if (has_filename())
+ __pn_ += preferred_separator;
+ __pn_ += __p.native();
+ return *this;
+ }
+
+ // FIXME: Use _LIBCPP_DIAGNOSE_WARNING to produce a diagnostic when __src
+ // is known at compile time to be "/' since the user almost certainly intended
+ // to append a separator instead of overwriting the path with "/"
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI _EnableIfPathable<_Source> operator/=(const _Source& __src) {
+ return this->append(__src);
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI _EnableIfPathable<_Source> append(const _Source& __src) {
+ using _Traits = __is_pathable<_Source>;
+ using _CVT = _PathCVT<_SourceChar<_Source> >;
+ bool __source_is_absolute = filesystem::__is_separator(_Traits::__first_or_null(__src));
+ if (__source_is_absolute)
+ __pn_.clear();
+ else if (has_filename())
+ __pn_ += preferred_separator;
+ _CVT::__append_source(__pn_, __src);
+ return *this;
+ }
+
+ template <class _InputIt>
+ _LIBCPP_HIDE_FROM_ABI path& append(_InputIt __first, _InputIt __last) {
+ typedef typename iterator_traits<_InputIt>::value_type _ItVal;
+ static_assert(__can_convert_char<_ItVal>::value, "Must convertible");
+ using _CVT = _PathCVT<_ItVal>;
+ if (__first != __last && filesystem::__is_separator(*__first))
+ __pn_.clear();
+ else if (has_filename())
+ __pn_ += preferred_separator;
+ _CVT::__append_range(__pn_, __first, __last);
+ return *this;
+ }
+# endif
+
+ // concatenation
+ _LIBCPP_HIDE_FROM_ABI path& operator+=(const path& __x) {
+ __pn_ += __x.__pn_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& operator+=(const string_type& __x) {
+ __pn_ += __x;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& operator+=(__string_view __x) {
+ __pn_ += __x;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& operator+=(const value_type* __x) {
+ __pn_ += __x;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& operator+=(value_type __x) {
+ __pn_ += __x;
+ return *this;
+ }
+
+ template <class _ECharT, __enable_if_t<__can_convert_char<_ECharT>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI path& operator+=(_ECharT __x) {
+ _PathCVT<_ECharT>::__append_source(__pn_, basic_string_view<_ECharT>(&__x, 1));
+ return *this;
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI _EnableIfPathable<_Source> operator+=(const _Source& __x) {
+ return this->concat(__x);
+ }
+
+ template <class _Source>
+ _LIBCPP_HIDE_FROM_ABI _EnableIfPathable<_Source> concat(const _Source& __x) {
+ _SourceCVT<_Source>::__append_source(__pn_, __x);
+ return *this;
+ }
+
+ template <class _InputIt>
+ _LIBCPP_HIDE_FROM_ABI path& concat(_InputIt __first, _InputIt __last) {
+ typedef typename iterator_traits<_InputIt>::value_type _ItVal;
+ _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
+ return *this;
+ }
+
+ // modifiers
+ _LIBCPP_HIDE_FROM_ABI void clear() noexcept { __pn_.clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI path& make_preferred() {
+# if defined(_LIBCPP_WIN32API)
+ std::replace(__pn_.begin(), __pn_.end(), L'/', L'\\');
+# endif
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& remove_filename() {
+ auto __fname = __filename();
+ if (!__fname.empty())
+ __pn_.erase(__fname.data() - __pn_.data());
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI path& replace_filename(const path& __replacement) {
+ remove_filename();
+ return (*this /= __replacement);
+ }
+
+ path& replace_extension(const path& __replacement = path());
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const path& __lhs, const path& __rhs) noexcept {
+ return __lhs.__compare(__rhs.__pn_) == 0;
+ }
+# if _LIBCPP_STD_VER <= 17
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const path& __lhs, const path& __rhs) noexcept {
+ return __lhs.__compare(__rhs.__pn_) != 0;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator<(const path& __lhs, const path& __rhs) noexcept {
+ return __lhs.__compare(__rhs.__pn_) < 0;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator<=(const path& __lhs, const path& __rhs) noexcept {
+ return __lhs.__compare(__rhs.__pn_) <= 0;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator>(const path& __lhs, const path& __rhs) noexcept {
+ return __lhs.__compare(__rhs.__pn_) > 0;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator>=(const path& __lhs, const path& __rhs) noexcept {
+ return __lhs.__compare(__rhs.__pn_) >= 0;
+ }
+# else // _LIBCPP_STD_VER <= 17
+ friend _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(const path& __lhs, const path& __rhs) noexcept {
+ return __lhs.__compare(__rhs.__pn_) <=> 0;
+ }
+# endif // _LIBCPP_STD_VER <= 17
+
+ friend _LIBCPP_HIDE_FROM_ABI path operator/(const path& __lhs, const path& __rhs) {
+ path __result(__lhs);
+ __result /= __rhs;
+ return __result;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(path& __rhs) noexcept { __pn_.swap(__rhs.__pn_); }
+
+ // private helper to allow reserving memory in the path
+ _LIBCPP_HIDE_FROM_ABI void __reserve(size_t __s) { __pn_.reserve(__s); }
+
+ // native format observers
+ _LIBCPP_HIDE_FROM_ABI const string_type& native() const noexcept { return __pn_; }
+
+ _LIBCPP_HIDE_FROM_ABI const value_type* c_str() const noexcept { return __pn_.c_str(); }
+
+ _LIBCPP_HIDE_FROM_ABI operator string_type() const { return __pn_; }
+
+# if defined(_LIBCPP_WIN32API)
+ _LIBCPP_HIDE_FROM_ABI std::wstring wstring() const { return __pn_; }
+
+ _LIBCPP_HIDE_FROM_ABI std::wstring generic_wstring() const {
+ std::wstring __s;
+ __s.resize(__pn_.size());
+ std::replace_copy(__pn_.begin(), __pn_.end(), __s.begin(), '\\', '/');
+ return __s;
+ }
+
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ template <class _ECharT, class _Traits = char_traits<_ECharT>, class _Allocator = allocator<_ECharT> >
+ _LIBCPP_HIDE_FROM_ABI basic_string<_ECharT, _Traits, _Allocator> string(const _Allocator& __a = _Allocator()) const {
+ using _Str = basic_string<_ECharT, _Traits, _Allocator>;
+ _Str __s(__a);
+ __s.reserve(__pn_.size());
+ _PathExport<_ECharT>::__append(__s, __pn_);
+ return __s;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI std::string string() const { return string<char>(); }
+ _LIBCPP_HIDE_FROM_ABI __u8_string u8string() const {
+ using _CVT = __narrow_to_utf8<sizeof(wchar_t) * __CHAR_BIT__>;
+ __u8_string __s;
+ __s.reserve(__pn_.size());
+ _CVT()(back_inserter(__s), __pn_.data(), __pn_.data() + __pn_.size());
+ return __s;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI std::u16string u16string() const { return string<char16_t>(); }
+ _LIBCPP_HIDE_FROM_ABI std::u32string u32string() const { return string<char32_t>(); }
+
+ // generic format observers
+ template <class _ECharT, class _Traits = char_traits<_ECharT>, class _Allocator = allocator<_ECharT> >
+ _LIBCPP_HIDE_FROM_ABI basic_string<_ECharT, _Traits, _Allocator>
+ generic_string(const _Allocator& __a = _Allocator()) const {
+ using _Str = basic_string<_ECharT, _Traits, _Allocator>;
+ _Str __s = string<_ECharT, _Traits, _Allocator>(__a);
+ // Note: This (and generic_u8string below) is slightly suboptimal as
+ // it iterates twice over the string; once to convert it to the right
+ // character type, and once to replace path delimiters.
+ std::replace(__s.begin(), __s.end(), static_cast<_ECharT>('\\'), static_cast<_ECharT>('/'));
+ return __s;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI std::string generic_string() const { return generic_string<char>(); }
+ _LIBCPP_HIDE_FROM_ABI std::u16string generic_u16string() const { return generic_string<char16_t>(); }
+ _LIBCPP_HIDE_FROM_ABI std::u32string generic_u32string() const { return generic_string<char32_t>(); }
+ _LIBCPP_HIDE_FROM_ABI __u8_string generic_u8string() const {
+ __u8_string __s = u8string();
+ std::replace(__s.begin(), __s.end(), '\\', '/');
+ return __s;
+ }
+# endif /* !_LIBCPP_HAS_NO_LOCALIZATION */
+# else /* _LIBCPP_WIN32API */
+
+ _LIBCPP_HIDE_FROM_ABI std::string string() const { return __pn_; }
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+ _LIBCPP_HIDE_FROM_ABI std::u8string u8string() const { return std::u8string(__pn_.begin(), __pn_.end()); }
+# else
+ _LIBCPP_HIDE_FROM_ABI std::string u8string() const { return __pn_; }
+# endif
+
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ template <class _ECharT, class _Traits = char_traits<_ECharT>, class _Allocator = allocator<_ECharT> >
+ _LIBCPP_HIDE_FROM_ABI basic_string<_ECharT, _Traits, _Allocator> string(const _Allocator& __a = _Allocator()) const {
+ using _CVT = __widen_from_utf8<sizeof(_ECharT) * __CHAR_BIT__>;
+ using _Str = basic_string<_ECharT, _Traits, _Allocator>;
+ _Str __s(__a);
+ __s.reserve(__pn_.size());
+ _CVT()(std::back_inserter(__s), __pn_.data(), __pn_.data() + __pn_.size());
+ return __s;
+ }
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ _LIBCPP_HIDE_FROM_ABI std::wstring wstring() const { return string<wchar_t>(); }
+# endif
+ _LIBCPP_HIDE_FROM_ABI std::u16string u16string() const { return string<char16_t>(); }
+ _LIBCPP_HIDE_FROM_ABI std::u32string u32string() const { return string<char32_t>(); }
+# endif /* !_LIBCPP_HAS_NO_LOCALIZATION */
+
+ // generic format observers
+ _LIBCPP_HIDE_FROM_ABI std::string generic_string() const { return __pn_; }
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+ _LIBCPP_HIDE_FROM_ABI std::u8string generic_u8string() const { return std::u8string(__pn_.begin(), __pn_.end()); }
+# else
+ _LIBCPP_HIDE_FROM_ABI std::string generic_u8string() const { return __pn_; }
+# endif
+
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ template <class _ECharT, class _Traits = char_traits<_ECharT>, class _Allocator = allocator<_ECharT> >
+ _LIBCPP_HIDE_FROM_ABI basic_string<_ECharT, _Traits, _Allocator>
+ generic_string(const _Allocator& __a = _Allocator()) const {
+ return string<_ECharT, _Traits, _Allocator>(__a);
+ }
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ _LIBCPP_HIDE_FROM_ABI std::wstring generic_wstring() const { return string<wchar_t>(); }
+# endif
+ _LIBCPP_HIDE_FROM_ABI std::u16string generic_u16string() const { return string<char16_t>(); }
+ _LIBCPP_HIDE_FROM_ABI std::u32string generic_u32string() const { return string<char32_t>(); }
+# endif /* !_LIBCPP_HAS_NO_LOCALIZATION */
+# endif /* !_LIBCPP_WIN32API */
+
+private:
+ int __compare(__string_view) const;
+ __string_view __root_name() const;
+ __string_view __root_directory() const;
+ __string_view __root_path_raw() const;
+ __string_view __relative_path() const;
+ __string_view __parent_path() const;
+ __string_view __filename() const;
+ __string_view __stem() const;
+ __string_view __extension() const;
+
+public:
+ // compare
+ _LIBCPP_HIDE_FROM_ABI int compare(const path& __p) const noexcept { return __compare(__p.__pn_); }
+ _LIBCPP_HIDE_FROM_ABI int compare(const string_type& __s) const { return __compare(__s); }
+ _LIBCPP_HIDE_FROM_ABI int compare(__string_view __s) const { return __compare(__s); }
+ _LIBCPP_HIDE_FROM_ABI int compare(const value_type* __s) const { return __compare(__s); }
+
+ // decomposition
+ _LIBCPP_HIDE_FROM_ABI path root_name() const { return string_type(__root_name()); }
+ _LIBCPP_HIDE_FROM_ABI path root_directory() const { return string_type(__root_directory()); }
+ _LIBCPP_HIDE_FROM_ABI path root_path() const {
+# if defined(_LIBCPP_WIN32API)
+ return string_type(__root_path_raw());
+# else
+ return root_name().append(string_type(__root_directory()));
+# endif
+ }
+ _LIBCPP_HIDE_FROM_ABI path relative_path() const { return string_type(__relative_path()); }
+ _LIBCPP_HIDE_FROM_ABI path parent_path() const { return string_type(__parent_path()); }
+ _LIBCPP_HIDE_FROM_ABI path filename() const { return string_type(__filename()); }
+ _LIBCPP_HIDE_FROM_ABI path stem() const { return string_type(__stem()); }
+ _LIBCPP_HIDE_FROM_ABI path extension() const { return string_type(__extension()); }
+
+ // query
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const noexcept { return __pn_.empty(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool has_root_name() const { return !__root_name().empty(); }
+ _LIBCPP_HIDE_FROM_ABI bool has_root_directory() const { return !__root_directory().empty(); }
+ _LIBCPP_HIDE_FROM_ABI bool has_root_path() const { return !__root_path_raw().empty(); }
+ _LIBCPP_HIDE_FROM_ABI bool has_relative_path() const { return !__relative_path().empty(); }
+ _LIBCPP_HIDE_FROM_ABI bool has_parent_path() const { return !__parent_path().empty(); }
+ _LIBCPP_HIDE_FROM_ABI bool has_filename() const { return !__filename().empty(); }
+ _LIBCPP_HIDE_FROM_ABI bool has_stem() const { return !__stem().empty(); }
+ _LIBCPP_HIDE_FROM_ABI bool has_extension() const { return !__extension().empty(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_absolute() const {
+# if defined(_LIBCPP_WIN32API)
+ __string_view __root_name_str = __root_name();
+ __string_view __root_dir = __root_directory();
+ if (__root_name_str.size() == 2 && __root_name_str[1] == ':') {
+ // A drive letter with no root directory is relative, e.g. x:example.
+ return !__root_dir.empty();
+ }
+ // If no root name, it's relative, e.g. \example is relative to the current drive
+ if (__root_name_str.empty())
+ return false;
+ if (__root_name_str.size() < 3)
+ return false;
+ // A server root name, like \\server, is always absolute
+ if (__root_name_str[0] != '/' && __root_name_str[0] != '\\')
+ return false;
+ if (__root_name_str[1] != '/' && __root_name_str[1] != '\\')
+ return false;
+ // Seems to be a server root name
+ return true;
+# else
+ return has_root_directory();
+# endif
+ }
+ _LIBCPP_HIDE_FROM_ABI bool is_relative() const { return !is_absolute(); }
+
+ // relative paths
+ path lexically_normal() const;
+ path lexically_relative(const path& __base) const;
+
+ _LIBCPP_HIDE_FROM_ABI path lexically_proximate(const path& __base) const {
+ path __result = this->lexically_relative(__base);
+ if (__result.native().empty())
+ return *this;
+ return __result;
+ }
+
+ // iterators
+ class _LIBCPP_EXPORTED_FROM_ABI iterator;
+ typedef iterator const_iterator;
+
+ iterator begin() const;
+ iterator end() const;
+
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+ template <
+ class _CharT,
+ class _Traits,
+ __enable_if_t<is_same<_CharT, value_type>::value && is_same<_Traits, char_traits<value_type> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const path& __p) {
+ __os << std::__quoted(__p.native());
+ return __os;
+ }
+
+ template <
+ class _CharT,
+ class _Traits,
+ __enable_if_t<!is_same<_CharT, value_type>::value || !is_same<_Traits, char_traits<value_type> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const path& __p) {
+ __os << std::__quoted(__p.string<_CharT, _Traits>());
+ return __os;
+ }
+
+ template <class _CharT, class _Traits>
+ _LIBCPP_HIDE_FROM_ABI friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, path& __p) {
+ basic_string<_CharT, _Traits> __tmp;
+ __is >> std::__quoted(__tmp);
+ __p = __tmp;
+ return __is;
+ }
+# endif // !_LIBCPP_HAS_NO_LOCALIZATION
+
+private:
+ inline _LIBCPP_HIDE_FROM_ABI path& __assign_view(__string_view const& __s) {
+ __pn_ = string_type(__s);
+ return *this;
+ }
+ string_type __pn_;
+};
+
+inline _LIBCPP_HIDE_FROM_ABI void swap(path& __lhs, path& __rhs) noexcept { __lhs.swap(__rhs); }
+
+_LIBCPP_EXPORTED_FROM_ABI size_t hash_value(const path& __p) noexcept;
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <>
+struct _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY hash<filesystem::path> : __unary_function<filesystem::path, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(filesystem::path const& __p) const noexcept {
+ return filesystem::hash_value(__p);
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FILESYSTEM_PATH_H
diff --git a/libcxx/include/__cxx03/__filesystem/path_iterator.h b/libcxx/include/__cxx03/__filesystem/path_iterator.h
new file mode 100644
index 00000000000000..f4d486d86cf380
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/path_iterator.h
@@ -0,0 +1,115 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_PATH_ITERATOR_H
+#define _LIBCPP___FILESYSTEM_PATH_ITERATOR_H
+
+#include <__assert>
+#include <__config>
+#include <__filesystem/path.h>
+#include <__iterator/iterator_traits.h>
+#include <cstddef>
+#include <string>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+class _LIBCPP_EXPORTED_FROM_ABI path::iterator {
+public:
+ enum _ParserState : unsigned char {
+ _Singular,
+ _BeforeBegin,
+ _InRootName,
+ _InRootDir,
+ _InFilenames,
+ _InTrailingSep,
+ _AtEnd
+ };
+
+public:
+ typedef input_iterator_tag iterator_category;
+ typedef bidirectional_iterator_tag iterator_concept;
+
+ typedef path value_type;
+ typedef ptrdiff_t difference_type;
+ typedef const path* pointer;
+ typedef path reference;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI iterator() : __stashed_elem_(), __path_ptr_(nullptr), __entry_(), __state_(_Singular) {}
+
+ _LIBCPP_HIDE_FROM_ABI iterator(const iterator&) = default;
+ _LIBCPP_HIDE_FROM_ABI ~iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI iterator& operator=(const iterator&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __stashed_elem_; }
+
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return &__stashed_elem_; }
+
+ _LIBCPP_HIDE_FROM_ABI iterator& operator++() {
+ _LIBCPP_ASSERT_NON_NULL(__state_ != _Singular, "attempting to increment a singular iterator");
+ _LIBCPP_ASSERT_UNCATEGORIZED(__state_ != _AtEnd, "attempting to increment the end iterator");
+ return __increment();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator operator++(int) {
+ iterator __it(*this);
+ this->operator++();
+ return __it;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator& operator--() {
+ _LIBCPP_ASSERT_NON_NULL(__state_ != _Singular, "attempting to decrement a singular iterator");
+ _LIBCPP_ASSERT_UNCATEGORIZED(
+ __entry_.data() != __path_ptr_->native().data(), "attempting to decrement the begin iterator");
+ return __decrement();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator operator--(int) {
+ iterator __it(*this);
+ this->operator--();
+ return __it;
+ }
+
+private:
+ friend class path;
+
+ inline _LIBCPP_HIDE_FROM_ABI friend bool operator==(const iterator&, const iterator&);
+
+ iterator& __increment();
+ iterator& __decrement();
+
+ path __stashed_elem_;
+ const path* __path_ptr_;
+ path::__string_view __entry_;
+ _ParserState __state_;
+};
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const path::iterator& __lhs, const path::iterator& __rhs) {
+ return __lhs.__path_ptr_ == __rhs.__path_ptr_ && __lhs.__entry_.data() == __rhs.__entry_.data();
+}
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const path::iterator& __lhs, const path::iterator& __rhs) {
+ return !(__lhs == __rhs);
+}
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_PATH_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__filesystem/perm_options.h b/libcxx/include/__cxx03/__filesystem/perm_options.h
new file mode 100644
index 00000000000000..64c16ee60a17d0
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/perm_options.h
@@ -0,0 +1,57 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_PERM_OPTIONS_H
+#define _LIBCPP___FILESYSTEM_PERM_OPTIONS_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+enum class perm_options : unsigned char { replace = 1, add = 2, remove = 4, nofollow = 8 };
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr perm_options operator&(perm_options __lhs, perm_options __rhs) {
+ return static_cast<perm_options>(static_cast<unsigned>(__lhs) & static_cast<unsigned>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr perm_options operator|(perm_options __lhs, perm_options __rhs) {
+ return static_cast<perm_options>(static_cast<unsigned>(__lhs) | static_cast<unsigned>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr perm_options operator^(perm_options __lhs, perm_options __rhs) {
+ return static_cast<perm_options>(static_cast<unsigned>(__lhs) ^ static_cast<unsigned>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr perm_options operator~(perm_options __lhs) {
+ return static_cast<perm_options>(~static_cast<unsigned>(__lhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline perm_options& operator&=(perm_options& __lhs, perm_options __rhs) {
+ return __lhs = __lhs & __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline perm_options& operator|=(perm_options& __lhs, perm_options __rhs) {
+ return __lhs = __lhs | __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline perm_options& operator^=(perm_options& __lhs, perm_options __rhs) {
+ return __lhs = __lhs ^ __rhs;
+}
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_PERM_OPTIONS_H
diff --git a/libcxx/include/__cxx03/__filesystem/perms.h b/libcxx/include/__cxx03/__filesystem/perms.h
new file mode 100644
index 00000000000000..458f1e6e534833
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/perms.h
@@ -0,0 +1,80 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_PERMS_H
+#define _LIBCPP___FILESYSTEM_PERMS_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+// On Windows, these permission bits map to one single readonly flag per
+// file, and the executable bit is always returned as set. When setting
+// permissions, as long as the write bit is set for either owner, group or
+// others, the readonly flag is cleared.
+enum class perms : unsigned {
+ none = 0,
+
+ owner_read = 0400,
+ owner_write = 0200,
+ owner_exec = 0100,
+ owner_all = 0700,
+
+ group_read = 040,
+ group_write = 020,
+ group_exec = 010,
+ group_all = 070,
+
+ others_read = 04,
+ others_write = 02,
+ others_exec = 01,
+ others_all = 07,
+
+ all = 0777,
+
+ set_uid = 04000,
+ set_gid = 02000,
+ sticky_bit = 01000,
+ mask = 07777,
+ unknown = 0xFFFF,
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr perms operator&(perms __lhs, perms __rhs) {
+ return static_cast<perms>(static_cast<unsigned>(__lhs) & static_cast<unsigned>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr perms operator|(perms __lhs, perms __rhs) {
+ return static_cast<perms>(static_cast<unsigned>(__lhs) | static_cast<unsigned>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr perms operator^(perms __lhs, perms __rhs) {
+ return static_cast<perms>(static_cast<unsigned>(__lhs) ^ static_cast<unsigned>(__rhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr perms operator~(perms __lhs) {
+ return static_cast<perms>(~static_cast<unsigned>(__lhs));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline perms& operator&=(perms& __lhs, perms __rhs) { return __lhs = __lhs & __rhs; }
+
+_LIBCPP_HIDE_FROM_ABI inline perms& operator|=(perms& __lhs, perms __rhs) { return __lhs = __lhs | __rhs; }
+
+_LIBCPP_HIDE_FROM_ABI inline perms& operator^=(perms& __lhs, perms __rhs) { return __lhs = __lhs ^ __rhs; }
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_PERMS_H
diff --git a/libcxx/include/__cxx03/__filesystem/recursive_directory_iterator.h b/libcxx/include/__cxx03/__filesystem/recursive_directory_iterator.h
new file mode 100644
index 00000000000000..caa1396eb301fc
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/recursive_directory_iterator.h
@@ -0,0 +1,164 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_RECURSIVE_DIRECTORY_ITERATOR_H
+#define _LIBCPP___FILESYSTEM_RECURSIVE_DIRECTORY_ITERATOR_H
+
+#include <__config>
+#include <__filesystem/directory_entry.h>
+#include <__filesystem/directory_options.h>
+#include <__filesystem/path.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/shared_ptr.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/enable_view.h>
+#include <__system_error/error_code.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH
+
+class recursive_directory_iterator {
+public:
+ using value_type = directory_entry;
+ using difference_type = ptrdiff_t;
+ using pointer = directory_entry const*;
+ using reference = directory_entry const&;
+ using iterator_category = input_iterator_tag;
+
+public:
+ // constructors and destructor
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator() noexcept : __rec_(false) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit recursive_directory_iterator(
+ const path& __p, directory_options __xoptions = directory_options::none)
+ : recursive_directory_iterator(__p, __xoptions, nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator(const path& __p, directory_options __xoptions, error_code& __ec)
+ : recursive_directory_iterator(__p, __xoptions, &__ec) {}
+
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator(const path& __p, error_code& __ec)
+ : recursive_directory_iterator(__p, directory_options::none, &__ec) {}
+
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator(const recursive_directory_iterator&) = default;
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator(recursive_directory_iterator&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator& operator=(const recursive_directory_iterator&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator& operator=(recursive_directory_iterator&& __o) noexcept {
+ // non-default implementation provided to support self-move assign.
+ if (this != &__o) {
+ __imp_ = std::move(__o.__imp_);
+ __rec_ = __o.__rec_;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~recursive_directory_iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI const directory_entry& operator*() const { return __dereference(); }
+
+ _LIBCPP_HIDE_FROM_ABI const directory_entry* operator->() const { return &__dereference(); }
+
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator& operator++() { return __increment(); }
+
+ _LIBCPP_HIDE_FROM_ABI __dir_element_proxy operator++(int) {
+ __dir_element_proxy __p(**this);
+ __increment();
+ return __p;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator& increment(error_code& __ec) { return __increment(&__ec); }
+
+ _LIBCPP_EXPORTED_FROM_ABI directory_options options() const;
+ _LIBCPP_EXPORTED_FROM_ABI int depth() const;
+
+ _LIBCPP_HIDE_FROM_ABI void pop() { __pop(); }
+
+ _LIBCPP_HIDE_FROM_ABI void pop(error_code& __ec) { __pop(&__ec); }
+
+ _LIBCPP_HIDE_FROM_ABI bool recursion_pending() const { return __rec_; }
+
+ _LIBCPP_HIDE_FROM_ABI void disable_recursion_pending() { __rec_ = false; }
+
+# if _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI bool operator==(default_sentinel_t) const noexcept {
+ return *this == recursive_directory_iterator();
+ }
+
+# endif
+
+private:
+ _LIBCPP_EXPORTED_FROM_ABI recursive_directory_iterator(const path& __p, directory_options __opt, error_code* __ec);
+ _LIBCPP_EXPORTED_FROM_ABI const directory_entry& __dereference() const;
+ _LIBCPP_EXPORTED_FROM_ABI bool __try_recursion(error_code* __ec);
+ _LIBCPP_EXPORTED_FROM_ABI void __advance(error_code* __ec = nullptr);
+ _LIBCPP_EXPORTED_FROM_ABI recursive_directory_iterator& __increment(error_code* __ec = nullptr);
+ _LIBCPP_EXPORTED_FROM_ABI void __pop(error_code* __ec = nullptr);
+
+ inline _LIBCPP_HIDE_FROM_ABI friend bool
+ operator==(const recursive_directory_iterator&, const recursive_directory_iterator&) noexcept;
+
+ struct _LIBCPP_HIDDEN __shared_imp;
+ shared_ptr<__shared_imp> __imp_;
+ bool __rec_;
+}; // class recursive_directory_iterator
+
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const recursive_directory_iterator& __lhs, const recursive_directory_iterator& __rhs) noexcept {
+ return __lhs.__imp_ == __rhs.__imp_;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline bool
+operator!=(const recursive_directory_iterator& __lhs, const recursive_directory_iterator& __rhs) noexcept {
+ return !(__lhs == __rhs);
+}
+// enable recursive_directory_iterator range-based for statements
+inline _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator begin(recursive_directory_iterator __iter) noexcept {
+ return __iter;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI recursive_directory_iterator end(recursive_directory_iterator) noexcept {
+ return recursive_directory_iterator();
+}
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+# if _LIBCPP_STD_VER >= 20
+
+template <>
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY inline constexpr bool
+ std::ranges::enable_borrowed_range<std::filesystem::recursive_directory_iterator> = true;
+
+template <>
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY inline constexpr bool
+ std::ranges::enable_view<std::filesystem::recursive_directory_iterator> = true;
+
+# endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FILESYSTEM_RECURSIVE_DIRECTORY_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__filesystem/space_info.h b/libcxx/include/__cxx03/__filesystem/space_info.h
new file mode 100644
index 00000000000000..3fa57d33096fc8
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/space_info.h
@@ -0,0 +1,38 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_SPACE_INFO_H
+#define _LIBCPP___FILESYSTEM_SPACE_INFO_H
+
+#include <__config>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+struct _LIBCPP_EXPORTED_FROM_ABI space_info {
+ uintmax_t capacity;
+ uintmax_t free;
+ uintmax_t available;
+
+# if _LIBCPP_STD_VER >= 20
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const space_info&, const space_info&) = default;
+# endif
+};
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_SPACE_INFO_H
diff --git a/libcxx/include/__cxx03/__filesystem/u8path.h b/libcxx/include/__cxx03/__filesystem/u8path.h
new file mode 100644
index 00000000000000..dae5823128f028
--- /dev/null
+++ b/libcxx/include/__cxx03/__filesystem/u8path.h
@@ -0,0 +1,100 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FILESYSTEM_U8PATH_H
+#define _LIBCPP___FILESYSTEM_U8PATH_H
+
+#include <__algorithm/unwrap_iter.h>
+#include <__config>
+#include <__filesystem/path.h>
+#include <string>
+
+// Only required on Windows for __widen_from_utf8, and included conservatively
+// because it requires support for localization.
+#if defined(_LIBCPP_WIN32API)
+# include <locale>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH
+
+template <class _InputIt, __enable_if_t<__is_pathable<_InputIt>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_DEPRECATED_WITH_CHAR8_T path u8path(_InputIt __f, _InputIt __l) {
+ static_assert(
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+ is_same<typename __is_pathable<_InputIt>::__char_type, char8_t>::value ||
+# endif
+ is_same<typename __is_pathable<_InputIt>::__char_type, char>::value,
+ "u8path(Iter, Iter) requires Iter have a value_type of type 'char'"
+ " or 'char8_t'");
+# if defined(_LIBCPP_WIN32API)
+ string __tmp(__f, __l);
+ using _CVT = __widen_from_utf8<sizeof(wchar_t) * __CHAR_BIT__>;
+ std::wstring __w;
+ __w.reserve(__tmp.size());
+ _CVT()(back_inserter(__w), __tmp.data(), __tmp.data() + __tmp.size());
+ return path(__w);
+# else
+ return path(__f, __l);
+# endif /* !_LIBCPP_WIN32API */
+}
+
+# if defined(_LIBCPP_WIN32API)
+template <class _InputIt, __enable_if_t<__is_pathable<_InputIt>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_DEPRECATED_WITH_CHAR8_T path u8path(_InputIt __f, _NullSentinel) {
+ static_assert(
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+ is_same<typename __is_pathable<_InputIt>::__char_type, char8_t>::value ||
+# endif
+ is_same<typename __is_pathable<_InputIt>::__char_type, char>::value,
+ "u8path(Iter, Iter) requires Iter have a value_type of type 'char'"
+ " or 'char8_t'");
+ string __tmp;
+ const char __sentinel = char{};
+ for (; *__f != __sentinel; ++__f)
+ __tmp.push_back(*__f);
+ using _CVT = __widen_from_utf8<sizeof(wchar_t) * __CHAR_BIT__>;
+ std::wstring __w;
+ __w.reserve(__tmp.size());
+ _CVT()(back_inserter(__w), __tmp.data(), __tmp.data() + __tmp.size());
+ return path(__w);
+}
+# endif /* _LIBCPP_WIN32API */
+
+template <class _Source, __enable_if_t<__is_pathable<_Source>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_DEPRECATED_WITH_CHAR8_T path u8path(const _Source& __s) {
+ static_assert(
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+ is_same<typename __is_pathable<_Source>::__char_type, char8_t>::value ||
+# endif
+ is_same<typename __is_pathable<_Source>::__char_type, char>::value,
+ "u8path(Source const&) requires Source have a character type of type "
+ "'char' or 'char8_t'");
+# if defined(_LIBCPP_WIN32API)
+ using _Traits = __is_pathable<_Source>;
+ return u8path(std::__unwrap_iter(_Traits::__range_begin(__s)), std::__unwrap_iter(_Traits::__range_end(__s)));
+# else
+ return path(__s);
+# endif
+}
+
+_LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FILESYSTEM_U8PATH_H
diff --git a/libcxx/include/__cxx03/__format/buffer.h b/libcxx/include/__cxx03/__format/buffer.h
new file mode 100644
index 00000000000000..8598f0a1c03957
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/buffer.h
@@ -0,0 +1,655 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_BUFFER_H
+#define _LIBCPP___FORMAT_BUFFER_H
+
+#include <__algorithm/copy_n.h>
+#include <__algorithm/fill_n.h>
+#include <__algorithm/max.h>
+#include <__algorithm/min.h>
+#include <__algorithm/ranges_copy_n.h>
+#include <__algorithm/transform.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/enable_insertable.h>
+#include <__format/format_to_n_result.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/wrap_iter.h>
+#include <__memory/addressof.h>
+#include <__memory/allocate_at_least.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/construct_at.h>
+#include <__memory/ranges_construct_at.h>
+#include <__memory/uninitialized_algorithms.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/conditional.h>
+#include <__utility/exception_guard.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __format {
+
+/// A "buffer" that handles writing to the proper iterator.
+///
+/// This helper is used together with the @ref back_insert_iterator to offer
+/// type-erasure for the formatting functions. This reduces the number to
+/// template instantiations.
+template <__fmt_char_type _CharT>
+class _LIBCPP_TEMPLATE_VIS __output_buffer {
+public:
+ using value_type = _CharT;
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI explicit __output_buffer(_CharT* __ptr, size_t __capacity, _Tp* __obj)
+ : __ptr_(__ptr),
+ __capacity_(__capacity),
+ __flush_([](_CharT* __p, size_t __n, void* __o) { static_cast<_Tp*>(__o)->__flush(__p, __n); }),
+ __obj_(__obj) {}
+
+ _LIBCPP_HIDE_FROM_ABI void __reset(_CharT* __ptr, size_t __capacity) {
+ __ptr_ = __ptr;
+ __capacity_ = __capacity;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI auto __make_output_iterator() { return std::back_insert_iterator{*this}; }
+
+ // Used in std::back_insert_iterator.
+ _LIBCPP_HIDE_FROM_ABI void push_back(_CharT __c) {
+ __ptr_[__size_++] = __c;
+
+ // Profiling showed flushing after adding is more efficient than flushing
+ // when entering the function.
+ if (__size_ == __capacity_)
+ __flush();
+ }
+
+ /// Copies the input __str to the buffer.
+ ///
+ /// Since some of the input is generated by std::to_chars, there needs to be a
+ /// conversion when _CharT is wchar_t.
+ template <__fmt_char_type _InCharT>
+ _LIBCPP_HIDE_FROM_ABI void __copy(basic_string_view<_InCharT> __str) {
+ // When the underlying iterator is a simple iterator the __capacity_ is
+ // infinite. For a string or container back_inserter it isn't. This means
+ // that adding a large string to the buffer can cause some overhead. In that
+ // case a better approach could be:
+ // - flush the buffer
+ // - container.append(__str.begin(), __str.end());
+ // The same holds true for the fill.
+ // For transform it might be slightly harder, however the use case for
+ // transform is slightly less common; it converts hexadecimal values to
+ // upper case. For integral these strings are short.
+ // TODO FMT Look at the improvements above.
+ size_t __n = __str.size();
+
+ __flush_on_overflow(__n);
+ if (__n < __capacity_) { // push_back requires the buffer to have room for at least one character (so use <).
+ std::copy_n(__str.data(), __n, std::addressof(__ptr_[__size_]));
+ __size_ += __n;
+ return;
+ }
+
+ // The output doesn't fit in the internal buffer.
+ // Copy the data in "__capacity_" sized chunks.
+ _LIBCPP_ASSERT_INTERNAL(__size_ == 0, "the buffer should be flushed by __flush_on_overflow");
+ const _InCharT* __first = __str.data();
+ do {
+ size_t __chunk = std::min(__n, __capacity_);
+ std::copy_n(__first, __chunk, std::addressof(__ptr_[__size_]));
+ __size_ = __chunk;
+ __first += __chunk;
+ __n -= __chunk;
+ __flush();
+ } while (__n);
+ }
+
+ /// A std::transform wrapper.
+ ///
+ /// Like @ref __copy it may need to do type conversion.
+ template <contiguous_iterator _Iterator,
+ class _UnaryOperation,
+ __fmt_char_type _InCharT = typename iterator_traits<_Iterator>::value_type>
+ _LIBCPP_HIDE_FROM_ABI void __transform(_Iterator __first, _Iterator __last, _UnaryOperation __operation) {
+ _LIBCPP_ASSERT_INTERNAL(__first <= __last, "not a valid range");
+
+ size_t __n = static_cast<size_t>(__last - __first);
+ __flush_on_overflow(__n);
+ if (__n < __capacity_) { // push_back requires the buffer to have room for at least one character (so use <).
+ std::transform(__first, __last, std::addressof(__ptr_[__size_]), std::move(__operation));
+ __size_ += __n;
+ return;
+ }
+
+ // The output doesn't fit in the internal buffer.
+ // Transform the data in "__capacity_" sized chunks.
+ _LIBCPP_ASSERT_INTERNAL(__size_ == 0, "the buffer should be flushed by __flush_on_overflow");
+ do {
+ size_t __chunk = std::min(__n, __capacity_);
+ std::transform(__first, __first + __chunk, std::addressof(__ptr_[__size_]), __operation);
+ __size_ = __chunk;
+ __first += __chunk;
+ __n -= __chunk;
+ __flush();
+ } while (__n);
+ }
+
+ /// A \c fill_n wrapper.
+ _LIBCPP_HIDE_FROM_ABI void __fill(size_t __n, _CharT __value) {
+ __flush_on_overflow(__n);
+ if (__n < __capacity_) { // push_back requires the buffer to have room for at least one character (so use <).
+ std::fill_n(std::addressof(__ptr_[__size_]), __n, __value);
+ __size_ += __n;
+ return;
+ }
+
+ // The output doesn't fit in the internal buffer.
+ // Fill the buffer in "__capacity_" sized chunks.
+ _LIBCPP_ASSERT_INTERNAL(__size_ == 0, "the buffer should be flushed by __flush_on_overflow");
+ do {
+ size_t __chunk = std::min(__n, __capacity_);
+ std::fill_n(std::addressof(__ptr_[__size_]), __chunk, __value);
+ __size_ = __chunk;
+ __n -= __chunk;
+ __flush();
+ } while (__n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __flush() {
+ __flush_(__ptr_, __size_, __obj_);
+ __size_ = 0;
+ }
+
+private:
+ _CharT* __ptr_;
+ size_t __capacity_;
+ size_t __size_{0};
+ void (*__flush_)(_CharT*, size_t, void*);
+ void* __obj_;
+
+ /// Flushes the buffer when the output operation would overflow the buffer.
+ ///
+ /// A simple approach for the overflow detection would be something along the
+ /// lines:
+ /// \code
+ /// // The internal buffer is large enough.
+ /// if (__n <= __capacity_) {
+ /// // Flush when we really would overflow.
+ /// if (__size_ + __n >= __capacity_)
+ /// __flush();
+ /// ...
+ /// }
+ /// \endcode
+ ///
+ /// This approach works for all cases but one:
+ /// A __format_to_n_buffer_base where \ref __enable_direct_output is true.
+ /// In that case the \ref __capacity_ of the buffer changes during the first
+ /// \ref __flush. During that operation the output buffer switches from its
+ /// __writer_ to its __storage_. The \ref __capacity_ of the former depends
+ /// on the value of n, of the latter is a fixed size. For example:
+ /// - a format_to_n call with a 10'000 char buffer,
+ /// - the buffer is filled with 9'500 chars,
+ /// - adding 1'000 elements would overflow the buffer so the buffer gets
+ /// changed and the \ref __capacity_ decreases from 10'000 to
+ /// __buffer_size (256 at the time of writing).
+ ///
+ /// This means that the \ref __flush for this class may need to copy a part of
+ /// the internal buffer to the proper output. In this example there will be
+ /// 500 characters that need this copy operation.
+ ///
+ /// Note it would be more efficient to write 500 chars directly and then swap
+ /// the buffers. This would make the code more complex and \ref format_to_n is
+ /// not the most common use case. Therefore the optimization isn't done.
+ _LIBCPP_HIDE_FROM_ABI void __flush_on_overflow(size_t __n) {
+ if (__size_ + __n >= __capacity_)
+ __flush();
+ }
+};
+
+/// A storage using an internal buffer.
+///
+/// This storage is used when writing a single element to the output iterator
+/// is expensive.
+template <__fmt_char_type _CharT>
+class _LIBCPP_TEMPLATE_VIS __internal_storage {
+public:
+ _LIBCPP_HIDE_FROM_ABI _CharT* __begin() { return __buffer_; }
+
+ static constexpr size_t __buffer_size = 256 / sizeof(_CharT);
+
+private:
+ _CharT __buffer_[__buffer_size];
+};
+
+/// A storage writing directly to the storage.
+///
+/// This requires the storage to be a contiguous buffer of \a _CharT.
+/// Since the output is directly written to the underlying storage this class
+/// is just an empty class.
+template <__fmt_char_type _CharT>
+class _LIBCPP_TEMPLATE_VIS __direct_storage {};
+
+template <class _OutIt, class _CharT>
+concept __enable_direct_output =
+ __fmt_char_type<_CharT> &&
+ (same_as<_OutIt, _CharT*>
+ // TODO(hardening): the following check might not apply to hardened iterators and might need to be wrapped in an
+ // `#ifdef`.
+ || same_as<_OutIt, __wrap_iter<_CharT*>>);
+
+/// Write policy for directly writing to the underlying output.
+template <class _OutIt, __fmt_char_type _CharT>
+class _LIBCPP_TEMPLATE_VIS __writer_direct {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __writer_direct(_OutIt __out_it) : __out_it_(__out_it) {}
+
+ _LIBCPP_HIDE_FROM_ABI _OutIt __out_it() { return __out_it_; }
+
+ _LIBCPP_HIDE_FROM_ABI void __flush(_CharT*, size_t __n) {
+ // _OutIt can be a __wrap_iter<CharT*>. Therefore the original iterator
+ // is adjusted.
+ __out_it_ += __n;
+ }
+
+private:
+ _OutIt __out_it_;
+};
+
+/// Write policy for copying the buffer to the output.
+template <class _OutIt, __fmt_char_type _CharT>
+class _LIBCPP_TEMPLATE_VIS __writer_iterator {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __writer_iterator(_OutIt __out_it) : __out_it_{std::move(__out_it)} {}
+
+ _LIBCPP_HIDE_FROM_ABI _OutIt __out_it() && { return std::move(__out_it_); }
+
+ _LIBCPP_HIDE_FROM_ABI void __flush(_CharT* __ptr, size_t __n) {
+ __out_it_ = std::ranges::copy_n(__ptr, __n, std::move(__out_it_)).out;
+ }
+
+private:
+ _OutIt __out_it_;
+};
+
+/// Concept to see whether a \a _Container is insertable.
+///
+/// The concept is used to validate whether multiple calls to a
+/// \ref back_insert_iterator can be replace by a call to \c _Container::insert.
+///
+/// \note a \a _Container needs to opt-in to the concept by specializing
+/// \ref __enable_insertable.
+template <class _Container>
+concept __insertable =
+ __enable_insertable<_Container> && __fmt_char_type<typename _Container::value_type> &&
+ requires(_Container& __t,
+ add_pointer_t<typename _Container::value_type> __first,
+ add_pointer_t<typename _Container::value_type> __last) { __t.insert(__t.end(), __first, __last); };
+
+/// Extract the container type of a \ref back_insert_iterator.
+template <class _It>
+struct _LIBCPP_TEMPLATE_VIS __back_insert_iterator_container {
+ using type = void;
+};
+
+template <__insertable _Container>
+struct _LIBCPP_TEMPLATE_VIS __back_insert_iterator_container<back_insert_iterator<_Container>> {
+ using type = _Container;
+};
+
+/// Write policy for inserting the buffer in a container.
+template <class _Container>
+class _LIBCPP_TEMPLATE_VIS __writer_container {
+public:
+ using _CharT = typename _Container::value_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __writer_container(back_insert_iterator<_Container> __out_it)
+ : __container_{__out_it.__get_container()} {}
+
+ _LIBCPP_HIDE_FROM_ABI auto __out_it() { return std::back_inserter(*__container_); }
+
+ _LIBCPP_HIDE_FROM_ABI void __flush(_CharT* __ptr, size_t __n) {
+ __container_->insert(__container_->end(), __ptr, __ptr + __n);
+ }
+
+private:
+ _Container* __container_;
+};
+
+/// Selects the type of the writer used for the output iterator.
+template <class _OutIt, class _CharT>
+class _LIBCPP_TEMPLATE_VIS __writer_selector {
+ using _Container = typename __back_insert_iterator_container<_OutIt>::type;
+
+public:
+ using type =
+ conditional_t<!same_as<_Container, void>,
+ __writer_container<_Container>,
+ conditional_t<__enable_direct_output<_OutIt, _CharT>,
+ __writer_direct<_OutIt, _CharT>,
+ __writer_iterator<_OutIt, _CharT>>>;
+};
+
+/// The generic formatting buffer.
+template <class _OutIt, __fmt_char_type _CharT>
+ requires(output_iterator<_OutIt, const _CharT&>)
+class _LIBCPP_TEMPLATE_VIS __format_buffer {
+ using _Storage =
+ conditional_t<__enable_direct_output<_OutIt, _CharT>, __direct_storage<_CharT>, __internal_storage<_CharT>>;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __format_buffer(_OutIt __out_it)
+ requires(same_as<_Storage, __internal_storage<_CharT>>)
+ : __output_(__storage_.__begin(), __storage_.__buffer_size, this), __writer_(std::move(__out_it)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __format_buffer(_OutIt __out_it)
+ requires(same_as<_Storage, __direct_storage<_CharT>>)
+ : __output_(std::__unwrap_iter(__out_it), size_t(-1), this), __writer_(std::move(__out_it)) {}
+
+ _LIBCPP_HIDE_FROM_ABI auto __make_output_iterator() { return __output_.__make_output_iterator(); }
+
+ _LIBCPP_HIDE_FROM_ABI void __flush(_CharT* __ptr, size_t __n) { __writer_.__flush(__ptr, __n); }
+
+ _LIBCPP_HIDE_FROM_ABI _OutIt __out_it() && {
+ __output_.__flush();
+ return std::move(__writer_).__out_it();
+ }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS _Storage __storage_;
+ __output_buffer<_CharT> __output_;
+ typename __writer_selector<_OutIt, _CharT>::type __writer_;
+};
+
+/// A buffer that counts the number of insertions.
+///
+/// Since \ref formatted_size only needs to know the size, the output itself is
+/// discarded.
+template <__fmt_char_type _CharT>
+class _LIBCPP_TEMPLATE_VIS __formatted_size_buffer {
+public:
+ _LIBCPP_HIDE_FROM_ABI auto __make_output_iterator() { return __output_.__make_output_iterator(); }
+
+ _LIBCPP_HIDE_FROM_ABI void __flush(const _CharT*, size_t __n) { __size_ += __n; }
+
+ _LIBCPP_HIDE_FROM_ABI size_t __result() && {
+ __output_.__flush();
+ return __size_;
+ }
+
+private:
+ __internal_storage<_CharT> __storage_;
+ __output_buffer<_CharT> __output_{__storage_.__begin(), __storage_.__buffer_size, this};
+ size_t __size_{0};
+};
+
+/// The base of a buffer that counts and limits the number of insertions.
+template <class _OutIt, __fmt_char_type _CharT, bool>
+ requires(output_iterator<_OutIt, const _CharT&>)
+struct _LIBCPP_TEMPLATE_VIS __format_to_n_buffer_base {
+ using _Size = iter_difference_t<_OutIt>;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __format_to_n_buffer_base(_OutIt __out_it, _Size __max_size)
+ : __writer_(std::move(__out_it)), __max_size_(std::max(_Size(0), __max_size)) {}
+
+ _LIBCPP_HIDE_FROM_ABI void __flush(_CharT* __ptr, size_t __n) {
+ if (_Size(__size_) <= __max_size_)
+ __writer_.__flush(__ptr, std::min(_Size(__n), __max_size_ - __size_));
+ __size_ += __n;
+ }
+
+protected:
+ __internal_storage<_CharT> __storage_;
+ __output_buffer<_CharT> __output_{__storage_.__begin(), __storage_.__buffer_size, this};
+ typename __writer_selector<_OutIt, _CharT>::type __writer_;
+
+ _Size __max_size_;
+ _Size __size_{0};
+};
+
+/// The base of a buffer that counts and limits the number of insertions.
+///
+/// This version is used when \c __enable_direct_output<_OutIt, _CharT> == true.
+///
+/// This class limits the size available to the direct writer so it will not
+/// exceed the maximum number of code units.
+template <class _OutIt, __fmt_char_type _CharT>
+ requires(output_iterator<_OutIt, const _CharT&>)
+class _LIBCPP_TEMPLATE_VIS __format_to_n_buffer_base<_OutIt, _CharT, true> {
+ using _Size = iter_difference_t<_OutIt>;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __format_to_n_buffer_base(_OutIt __out_it, _Size __max_size)
+ : __output_(std::__unwrap_iter(__out_it), __max_size, this),
+ __writer_(std::move(__out_it)),
+ __max_size_(__max_size) {
+ if (__max_size <= 0) [[unlikely]]
+ __output_.__reset(__storage_.__begin(), __storage_.__buffer_size);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __flush(_CharT* __ptr, size_t __n) {
+ // A __flush to the direct writer happens in the following occasions:
+ // - The format function has written the maximum number of allowed code
+ // units. At this point it's no longer valid to write to this writer. So
+ // switch to the internal storage. This internal storage doesn't need to
+ // be written anywhere so the __flush for that storage writes no output.
+ // - Like above, but the next "mass write" operation would overflow the
+ // buffer. In that case the buffer is pre-emptively switched. The still
+ // valid code units will be written separately.
+ // - The format_to_n function is finished. In this case there's no need to
+ // switch the buffer, but for simplicity the buffers are still switched.
+ // When the __max_size <= 0 the constructor already switched the buffers.
+ if (__size_ == 0 && __ptr != __storage_.__begin()) {
+ __writer_.__flush(__ptr, __n);
+ __output_.__reset(__storage_.__begin(), __storage_.__buffer_size);
+ } else if (__size_ < __max_size_) {
+ // Copies a part of the internal buffer to the output up to n characters.
+ // See __output_buffer<_CharT>::__flush_on_overflow for more information.
+ _Size __s = std::min(_Size(__n), __max_size_ - __size_);
+ std::copy_n(__ptr, __s, __writer_.__out_it());
+ __writer_.__flush(__ptr, __s);
+ }
+
+ __size_ += __n;
+ }
+
+protected:
+ __internal_storage<_CharT> __storage_;
+ __output_buffer<_CharT> __output_;
+ __writer_direct<_OutIt, _CharT> __writer_;
+
+ _Size __max_size_;
+ _Size __size_{0};
+};
+
+/// The buffer that counts and limits the number of insertions.
+template <class _OutIt, __fmt_char_type _CharT>
+ requires(output_iterator<_OutIt, const _CharT&>)
+struct _LIBCPP_TEMPLATE_VIS __format_to_n_buffer final
+ : public __format_to_n_buffer_base< _OutIt, _CharT, __enable_direct_output<_OutIt, _CharT>> {
+ using _Base = __format_to_n_buffer_base<_OutIt, _CharT, __enable_direct_output<_OutIt, _CharT>>;
+ using _Size = iter_difference_t<_OutIt>;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __format_to_n_buffer(_OutIt __out_it, _Size __max_size)
+ : _Base(std::move(__out_it), __max_size) {}
+ _LIBCPP_HIDE_FROM_ABI auto __make_output_iterator() { return this->__output_.__make_output_iterator(); }
+
+ _LIBCPP_HIDE_FROM_ABI format_to_n_result<_OutIt> __result() && {
+ this->__output_.__flush();
+ return {std::move(this->__writer_).__out_it(), this->__size_};
+ }
+};
+
+// A dynamically growing buffer intended to be used for retargeting a context.
+//
+// P2286 Formatting ranges adds range formatting support. It allows the user to
+// specify the minimum width for the entire formatted range. The width of the
+// range is not known until the range is formatted. Formatting is done to an
+// output_iterator so there's no guarantee it would be possible to add the fill
+// to the front of the output. Instead the range is formatted to a temporary
+// buffer and that buffer is formatted as a string.
+//
+// There is an issue with that approach, the format context used in
+// std::formatter<T>::format contains the output iterator used as part of its
+// type. So using this output iterator means there needs to be a new format
+// context and the format arguments need to be retargeted to the new context.
+// This retargeting is done by a basic_format_context specialized for the
+// __iterator of this container.
+//
+// This class uses its own buffer management, since using vector
+// would lead to a circular include with formatter for vector<bool>.
+template <__fmt_char_type _CharT>
+class _LIBCPP_TEMPLATE_VIS __retarget_buffer {
+ using _Alloc = allocator<_CharT>;
+
+public:
+ using value_type = _CharT;
+
+ struct __iterator {
+ using difference_type = ptrdiff_t;
+ using value_type = _CharT;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(__retarget_buffer& __buffer)
+ : __buffer_(std::addressof(__buffer)) {}
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator=(const _CharT& __c) {
+ __buffer_->push_back(__c);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator=(_CharT&& __c) {
+ __buffer_->push_back(__c);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator*() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int) { return *this; }
+ __retarget_buffer* __buffer_;
+ };
+
+ __retarget_buffer(const __retarget_buffer&) = delete;
+ __retarget_buffer& operator=(const __retarget_buffer&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __retarget_buffer(size_t __size_hint) {
+ // When the initial size is very small a lot of resizes happen
+ // when elements added. So use a hard-coded minimum size.
+ //
+ // Note a size < 2 will not work
+ // - 0 there is no buffer, while push_back requires 1 empty element.
+ // - 1 multiplied by the grow factor is 1 and thus the buffer never
+ // grows.
+ auto __result = std::__allocate_at_least(__alloc_, std::max(__size_hint, 256 / sizeof(_CharT)));
+ __ptr_ = __result.ptr;
+ __capacity_ = __result.count;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~__retarget_buffer() {
+ ranges::destroy_n(__ptr_, __size_);
+ allocator_traits<_Alloc>::deallocate(__alloc_, __ptr_, __capacity_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator __make_output_iterator() { return __iterator{*this}; }
+
+ _LIBCPP_HIDE_FROM_ABI void push_back(_CharT __c) {
+ std::construct_at(__ptr_ + __size_, __c);
+ ++__size_;
+
+ if (__size_ == __capacity_)
+ __grow_buffer();
+ }
+
+ template <__fmt_char_type _InCharT>
+ _LIBCPP_HIDE_FROM_ABI void __copy(basic_string_view<_InCharT> __str) {
+ size_t __n = __str.size();
+ if (__size_ + __n >= __capacity_)
+ // Push_back requires the buffer to have room for at least one character.
+ __grow_buffer(__size_ + __n + 1);
+
+ std::uninitialized_copy_n(__str.data(), __n, __ptr_ + __size_);
+ __size_ += __n;
+ }
+
+ template <contiguous_iterator _Iterator,
+ class _UnaryOperation,
+ __fmt_char_type _InCharT = typename iterator_traits<_Iterator>::value_type>
+ _LIBCPP_HIDE_FROM_ABI void __transform(_Iterator __first, _Iterator __last, _UnaryOperation __operation) {
+ _LIBCPP_ASSERT_INTERNAL(__first <= __last, "not a valid range");
+
+ size_t __n = static_cast<size_t>(__last - __first);
+ if (__size_ + __n >= __capacity_)
+ // Push_back requires the buffer to have room for at least one character.
+ __grow_buffer(__size_ + __n + 1);
+
+ std::uninitialized_default_construct_n(__ptr_ + __size_, __n);
+ std::transform(__first, __last, __ptr_ + __size_, std::move(__operation));
+ __size_ += __n;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __fill(size_t __n, _CharT __value) {
+ if (__size_ + __n >= __capacity_)
+ // Push_back requires the buffer to have room for at least one character.
+ __grow_buffer(__size_ + __n + 1);
+
+ std::uninitialized_fill_n(__ptr_ + __size_, __n, __value);
+ __size_ += __n;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_string_view<_CharT> __view() { return {__ptr_, __size_}; }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI void __grow_buffer() { __grow_buffer(__capacity_ * 1.6); }
+
+ _LIBCPP_HIDE_FROM_ABI void __grow_buffer(size_t __capacity) {
+ _LIBCPP_ASSERT_INTERNAL(__capacity > __capacity_, "the buffer must grow");
+ auto __result = std::__allocate_at_least(__alloc_, __capacity);
+ auto __guard = std::__make_exception_guard([&] {
+ allocator_traits<_Alloc>::deallocate(__alloc_, __result.ptr, __result.count);
+ });
+ // This shouldn't throw, but just to be safe. Note that at -O1 this
+ // guard is optimized away so there is no runtime overhead.
+ std::uninitialized_move_n(__ptr_, __size_, __result.ptr);
+ __guard.__complete();
+ ranges::destroy_n(__ptr_, __size_);
+ allocator_traits<_Alloc>::deallocate(__alloc_, __ptr_, __capacity_);
+
+ __ptr_ = __result.ptr;
+ __capacity_ = __result.count;
+ }
+ _LIBCPP_NO_UNIQUE_ADDRESS _Alloc __alloc_;
+ _CharT* __ptr_;
+ size_t __capacity_;
+ size_t __size_{0};
+};
+
+} // namespace __format
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_BUFFER_H
diff --git a/libcxx/include/__cxx03/__format/concepts.h b/libcxx/include/__cxx03/__format/concepts.h
new file mode 100644
index 00000000000000..13380e9b91aff8
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/concepts.h
@@ -0,0 +1,83 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_CONCEPTS_H
+#define _LIBCPP___FORMAT_CONCEPTS_H
+
+#include <__concepts/same_as.h>
+#include <__concepts/semiregular.h>
+#include <__config>
+#include <__format/format_parse_context.h>
+#include <__fwd/format.h>
+#include <__fwd/tuple.h>
+#include <__tuple/tuple_size.h>
+#include <__type_traits/is_specialization.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+/// The character type specializations of \ref formatter.
+template <class _CharT>
+concept __fmt_char_type =
+ same_as<_CharT, char>
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ || same_as<_CharT, wchar_t>
+# endif
+ ;
+
+// The output iterator isn't specified. A formatter should accept any
+// output_iterator. This iterator is a minimal iterator to test the concept.
+// (Note testing for (w)format_context would be a valid choice, but requires
+// selecting the proper one depending on the type of _CharT.)
+template <class _CharT>
+using __fmt_iter_for = _CharT*;
+
+template <class _Tp, class _Context, class _Formatter = typename _Context::template formatter_type<remove_const_t<_Tp>>>
+concept __formattable_with =
+ semiregular<_Formatter> &&
+ requires(_Formatter& __f,
+ const _Formatter& __cf,
+ _Tp&& __t,
+ _Context __fc,
+ basic_format_parse_context<typename _Context::char_type> __pc) {
+ { __f.parse(__pc) } -> same_as<typename decltype(__pc)::iterator>;
+ { __cf.format(__t, __fc) } -> same_as<typename _Context::iterator>;
+ };
+
+template <class _Tp, class _CharT>
+concept __formattable =
+ __formattable_with<remove_reference_t<_Tp>, basic_format_context<__fmt_iter_for<_CharT>, _CharT>>;
+
+# if _LIBCPP_STD_VER >= 23
+template <class _Tp, class _CharT>
+concept formattable = __formattable<_Tp, _CharT>;
+
+// [tuple.like] defines a tuple-like exposition only concept. This concept is
+// not related to that. Therefore it uses a different name for the concept.
+//
+// TODO FMT Add a test to validate we fail when using that concept after P2165
+// has been implemented.
+template <class _Tp>
+concept __fmt_pair_like =
+ __is_specialization_v<_Tp, pair> || (__is_specialization_v<_Tp, tuple> && tuple_size_v<_Tp> == 2);
+
+# endif //_LIBCPP_STD_VER >= 23
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_CONCEPTS_H
diff --git a/libcxx/include/__cxx03/__format/container_adaptor.h b/libcxx/include/__cxx03/__format/container_adaptor.h
new file mode 100644
index 00000000000000..9f49ca03bf4f50
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/container_adaptor.h
@@ -0,0 +1,73 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_CONTAINER_ADAPTOR_H
+#define _LIBCPP___FORMAT_CONTAINER_ADAPTOR_H
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/formatter.h>
+#include <__format/range_default_formatter.h>
+#include <__fwd/queue.h>
+#include <__fwd/stack.h>
+#include <__ranges/ref_view.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/maybe_const.h>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+// [container.adaptors.format] only specifies the library should provide the
+// formatter specializations, not which header should provide them.
+// Since <format> includes a lot of headers, add these headers here instead of
+// adding more dependencies like, locale, optinal, string, tuple, etc. to the
+// adaptor headers. To use the format functions users already include <format>.
+
+template <class _Adaptor, class _CharT>
+struct _LIBCPP_TEMPLATE_VIS __formatter_container_adaptor {
+private:
+ using __maybe_const_container = __fmt_maybe_const<typename _Adaptor::container_type, _CharT>;
+ using __maybe_const_adaptor = __maybe_const<is_const_v<__maybe_const_container>, _Adaptor>;
+ formatter<ranges::ref_view<__maybe_const_container>, _CharT> __underlying_;
+
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return __underlying_.parse(__ctx);
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(__maybe_const_adaptor& __adaptor, _FormatContext& __ctx) const {
+ return __underlying_.format(__adaptor.__get_container(), __ctx);
+ }
+};
+
+template <class _CharT, class _Tp, formattable<_CharT> _Container>
+struct _LIBCPP_TEMPLATE_VIS formatter<queue<_Tp, _Container>, _CharT>
+ : public __formatter_container_adaptor<queue<_Tp, _Container>, _CharT> {};
+
+template <class _CharT, class _Tp, class _Container, class _Compare>
+struct _LIBCPP_TEMPLATE_VIS formatter<priority_queue<_Tp, _Container, _Compare>, _CharT>
+ : public __formatter_container_adaptor<priority_queue<_Tp, _Container, _Compare>, _CharT> {};
+
+template <class _CharT, class _Tp, formattable<_CharT> _Container>
+struct _LIBCPP_TEMPLATE_VIS formatter<stack<_Tp, _Container>, _CharT>
+ : public __formatter_container_adaptor<stack<_Tp, _Container>, _CharT> {};
+
+#endif //_LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_CONTAINER_ADAPTOR_H
diff --git a/libcxx/include/__cxx03/__format/enable_insertable.h b/libcxx/include/__cxx03/__format/enable_insertable.h
new file mode 100644
index 00000000000000..86ef94a325b192
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/enable_insertable.h
@@ -0,0 +1,35 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_ENABLE_INSERTABLE_H
+#define _LIBCPP___FORMAT_ENABLE_INSERTABLE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __format {
+
+/// Opt-in to enable \ref __insertable for a \a _Container.
+template <class _Container>
+inline constexpr bool __enable_insertable = false;
+
+} // namespace __format
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_ENABLE_INSERTABLE_H
diff --git a/libcxx/include/__cxx03/__format/escaped_output_table.h b/libcxx/include/__cxx03/__format/escaped_output_table.h
new file mode 100644
index 00000000000000..f7be2dc61f21a3
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/escaped_output_table.h
@@ -0,0 +1,863 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// WARNING, this entire header is generated by
+// utils/generate_escaped_output_table.py
+// DO NOT MODIFY!
+
+// UNICODE, INC. LICENSE AGREEMENT - DATA FILES AND SOFTWARE
+//
+// See Terms of Use <https://www.unicode.org/copyright.html>
+// for definitions of Unicode Inc.'s Data Files and Software.
+//
+// NOTICE TO USER: Carefully read the following legal agreement.
+// BY DOWNLOADING, INSTALLING, COPYING OR OTHERWISE USING UNICODE INC.'S
+// DATA FILES ("DATA FILES"), AND/OR SOFTWARE ("SOFTWARE"),
+// YOU UNEQUIVOCALLY ACCEPT, AND AGREE TO BE BOUND BY, ALL OF THE
+// TERMS AND CONDITIONS OF THIS AGREEMENT.
+// IF YOU DO NOT AGREE, DO NOT DOWNLOAD, INSTALL, COPY, DISTRIBUTE OR USE
+// THE DATA FILES OR SOFTWARE.
+//
+// COPYRIGHT AND PERMISSION NOTICE
+//
+// Copyright (c) 1991-2022 Unicode, Inc. All rights reserved.
+// Distributed under the Terms of Use in https://www.unicode.org/copyright.html.
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of the Unicode data files and any associated documentation
+// (the "Data Files") or Unicode software and any associated documentation
+// (the "Software") to deal in the Data Files or Software
+// without restriction, including without limitation the rights to use,
+// copy, modify, merge, publish, distribute, and/or sell copies of
+// the Data Files or Software, and to permit persons to whom the Data Files
+// or Software are furnished to do so, provided that either
+// (a) this copyright and permission notice appear with all copies
+// of the Data Files or Software, or
+// (b) this copyright and permission notice appear in associated
+// Documentation.
+//
+// THE DATA FILES AND SOFTWARE ARE PROVIDED "AS IS", WITHOUT WARRANTY OF
+// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+// WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+// IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS
+// NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL
+// DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+// DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THE DATA FILES OR SOFTWARE.
+//
+// Except as contained in this notice, the name of a copyright holder
+// shall not be used in advertising or otherwise to promote the sale,
+// use or other dealings in these Data Files or Software without prior
+// written authorization of the copyright holder.
+
+#ifndef _LIBCPP___FORMAT_ESCAPED_OUTPUT_TABLE_H
+#define _LIBCPP___FORMAT_ESCAPED_OUTPUT_TABLE_H
+
+#include <__algorithm/ranges_upper_bound.h>
+#include <__config>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+namespace __escaped_output_table {
+// clang-format off
+
+/// The entries of the characters to escape in format's debug string.
+///
+/// Contains the entries for [format.string.escaped]/2.2.1.2.1
+/// CE is a Unicode encoding and C corresponds to a UCS scalar value whose
+/// Unicode property General_Category has a value in the groups Separator (Z)
+/// or Other (C), as described by table 12 of UAX #44
+///
+/// Separator (Z) consists of General_Category
+/// - Space_Separator,
+/// - Line_Separator,
+/// - Paragraph_Separator.
+///
+/// Other (C) consists of General_Category
+/// - Control,
+/// - Format,
+/// - Surrogate,
+/// - Private_Use,
+/// - Unassigned.
+///
+/// The data is generated from
+/// - https://www.unicode.org/Public/UCD/latest/ucd/extracted/DerivedGeneralCategory.txt
+///
+/// The table is similar to the table
+/// __extended_grapheme_custer_property_boundary::__entries
+/// which explains the details of these classes. The only difference is this
+/// table lacks a property, thus having more bits available for the size.
+///
+/// The data has 2 values:
+/// - bits [0, 13] The size of the range, allowing 16384 elements.
+/// - bits [14, 31] The lower bound code point of the range. The upper bound of
+/// the range is lower bound + size. Note the code expects code units the fit
+/// into 18 bits, instead of the 21 bits needed for the full Unicode range.
+_LIBCPP_HIDE_FROM_ABI inline constexpr uint32_t __entries[711] = {
+ 0x00000020 /* 00000000 - 00000020 [ 33] */,
+ 0x001fc021 /* 0000007f - 000000a0 [ 34] */,
+ 0x002b4000 /* 000000ad - 000000ad [ 1] */,
+ 0x00de0001 /* 00000378 - 00000379 [ 2] */,
+ 0x00e00003 /* 00000380 - 00000383 [ 4] */,
+ 0x00e2c000 /* 0000038b - 0000038b [ 1] */,
+ 0x00e34000 /* 0000038d - 0000038d [ 1] */,
+ 0x00e88000 /* 000003a2 - 000003a2 [ 1] */,
+ 0x014c0000 /* 00000530 - 00000530 [ 1] */,
+ 0x0155c001 /* 00000557 - 00000558 [ 2] */,
+ 0x0162c001 /* 0000058b - 0000058c [ 2] */,
+ 0x01640000 /* 00000590 - 00000590 [ 1] */,
+ 0x01720007 /* 000005c8 - 000005cf [ 8] */,
+ 0x017ac003 /* 000005eb - 000005ee [ 4] */,
+ 0x017d4010 /* 000005f5 - 00000605 [ 17] */,
+ 0x01870000 /* 0000061c - 0000061c [ 1] */,
+ 0x01b74000 /* 000006dd - 000006dd [ 1] */,
+ 0x01c38001 /* 0000070e - 0000070f [ 2] */,
+ 0x01d2c001 /* 0000074b - 0000074c [ 2] */,
+ 0x01ec800d /* 000007b2 - 000007bf [ 14] */,
+ 0x01fec001 /* 000007fb - 000007fc [ 2] */,
+ 0x020b8001 /* 0000082e - 0000082f [ 2] */,
+ 0x020fc000 /* 0000083f - 0000083f [ 1] */,
+ 0x02170001 /* 0000085c - 0000085d [ 2] */,
+ 0x0217c000 /* 0000085f - 0000085f [ 1] */,
+ 0x021ac004 /* 0000086b - 0000086f [ 5] */,
+ 0x0223c008 /* 0000088f - 00000897 [ 9] */,
+ 0x02388000 /* 000008e2 - 000008e2 [ 1] */,
+ 0x02610000 /* 00000984 - 00000984 [ 1] */,
+ 0x02634001 /* 0000098d - 0000098e [ 2] */,
+ 0x02644001 /* 00000991 - 00000992 [ 2] */,
+ 0x026a4000 /* 000009a9 - 000009a9 [ 1] */,
+ 0x026c4000 /* 000009b1 - 000009b1 [ 1] */,
+ 0x026cc002 /* 000009b3 - 000009b5 [ 3] */,
+ 0x026e8001 /* 000009ba - 000009bb [ 2] */,
+ 0x02714001 /* 000009c5 - 000009c6 [ 2] */,
+ 0x02724001 /* 000009c9 - 000009ca [ 2] */,
+ 0x0273c007 /* 000009cf - 000009d6 [ 8] */,
+ 0x02760003 /* 000009d8 - 000009db [ 4] */,
+ 0x02778000 /* 000009de - 000009de [ 1] */,
+ 0x02790001 /* 000009e4 - 000009e5 [ 2] */,
+ 0x027fc001 /* 000009ff - 00000a00 [ 2] */,
+ 0x02810000 /* 00000a04 - 00000a04 [ 1] */,
+ 0x0282c003 /* 00000a0b - 00000a0e [ 4] */,
+ 0x02844001 /* 00000a11 - 00000a12 [ 2] */,
+ 0x028a4000 /* 00000a29 - 00000a29 [ 1] */,
+ 0x028c4000 /* 00000a31 - 00000a31 [ 1] */,
+ 0x028d0000 /* 00000a34 - 00000a34 [ 1] */,
+ 0x028dc000 /* 00000a37 - 00000a37 [ 1] */,
+ 0x028e8001 /* 00000a3a - 00000a3b [ 2] */,
+ 0x028f4000 /* 00000a3d - 00000a3d [ 1] */,
+ 0x0290c003 /* 00000a43 - 00000a46 [ 4] */,
+ 0x02924001 /* 00000a49 - 00000a4a [ 2] */,
+ 0x02938002 /* 00000a4e - 00000a50 [ 3] */,
+ 0x02948006 /* 00000a52 - 00000a58 [ 7] */,
+ 0x02974000 /* 00000a5d - 00000a5d [ 1] */,
+ 0x0297c006 /* 00000a5f - 00000a65 [ 7] */,
+ 0x029dc009 /* 00000a77 - 00000a80 [ 10] */,
+ 0x02a10000 /* 00000a84 - 00000a84 [ 1] */,
+ 0x02a38000 /* 00000a8e - 00000a8e [ 1] */,
+ 0x02a48000 /* 00000a92 - 00000a92 [ 1] */,
+ 0x02aa4000 /* 00000aa9 - 00000aa9 [ 1] */,
+ 0x02ac4000 /* 00000ab1 - 00000ab1 [ 1] */,
+ 0x02ad0000 /* 00000ab4 - 00000ab4 [ 1] */,
+ 0x02ae8001 /* 00000aba - 00000abb [ 2] */,
+ 0x02b18000 /* 00000ac6 - 00000ac6 [ 1] */,
+ 0x02b28000 /* 00000aca - 00000aca [ 1] */,
+ 0x02b38001 /* 00000ace - 00000acf [ 2] */,
+ 0x02b4400e /* 00000ad1 - 00000adf [ 15] */,
+ 0x02b90001 /* 00000ae4 - 00000ae5 [ 2] */,
+ 0x02bc8006 /* 00000af2 - 00000af8 [ 7] */,
+ 0x02c00000 /* 00000b00 - 00000b00 [ 1] */,
+ 0x02c10000 /* 00000b04 - 00000b04 [ 1] */,
+ 0x02c34001 /* 00000b0d - 00000b0e [ 2] */,
+ 0x02c44001 /* 00000b11 - 00000b12 [ 2] */,
+ 0x02ca4000 /* 00000b29 - 00000b29 [ 1] */,
+ 0x02cc4000 /* 00000b31 - 00000b31 [ 1] */,
+ 0x02cd0000 /* 00000b34 - 00000b34 [ 1] */,
+ 0x02ce8001 /* 00000b3a - 00000b3b [ 2] */,
+ 0x02d14001 /* 00000b45 - 00000b46 [ 2] */,
+ 0x02d24001 /* 00000b49 - 00000b4a [ 2] */,
+ 0x02d38006 /* 00000b4e - 00000b54 [ 7] */,
+ 0x02d60003 /* 00000b58 - 00000b5b [ 4] */,
+ 0x02d78000 /* 00000b5e - 00000b5e [ 1] */,
+ 0x02d90001 /* 00000b64 - 00000b65 [ 2] */,
+ 0x02de0009 /* 00000b78 - 00000b81 [ 10] */,
+ 0x02e10000 /* 00000b84 - 00000b84 [ 1] */,
+ 0x02e2c002 /* 00000b8b - 00000b8d [ 3] */,
+ 0x02e44000 /* 00000b91 - 00000b91 [ 1] */,
+ 0x02e58002 /* 00000b96 - 00000b98 [ 3] */,
+ 0x02e6c000 /* 00000b9b - 00000b9b [ 1] */,
+ 0x02e74000 /* 00000b9d - 00000b9d [ 1] */,
+ 0x02e80002 /* 00000ba0 - 00000ba2 [ 3] */,
+ 0x02e94002 /* 00000ba5 - 00000ba7 [ 3] */,
+ 0x02eac002 /* 00000bab - 00000bad [ 3] */,
+ 0x02ee8003 /* 00000bba - 00000bbd [ 4] */,
+ 0x02f0c002 /* 00000bc3 - 00000bc5 [ 3] */,
+ 0x02f24000 /* 00000bc9 - 00000bc9 [ 1] */,
+ 0x02f38001 /* 00000bce - 00000bcf [ 2] */,
+ 0x02f44005 /* 00000bd1 - 00000bd6 [ 6] */,
+ 0x02f6000d /* 00000bd8 - 00000be5 [ 14] */,
+ 0x02fec004 /* 00000bfb - 00000bff [ 5] */,
+ 0x03034000 /* 00000c0d - 00000c0d [ 1] */,
+ 0x03044000 /* 00000c11 - 00000c11 [ 1] */,
+ 0x030a4000 /* 00000c29 - 00000c29 [ 1] */,
+ 0x030e8001 /* 00000c3a - 00000c3b [ 2] */,
+ 0x03114000 /* 00000c45 - 00000c45 [ 1] */,
+ 0x03124000 /* 00000c49 - 00000c49 [ 1] */,
+ 0x03138006 /* 00000c4e - 00000c54 [ 7] */,
+ 0x0315c000 /* 00000c57 - 00000c57 [ 1] */,
+ 0x0316c001 /* 00000c5b - 00000c5c [ 2] */,
+ 0x03178001 /* 00000c5e - 00000c5f [ 2] */,
+ 0x03190001 /* 00000c64 - 00000c65 [ 2] */,
+ 0x031c0006 /* 00000c70 - 00000c76 [ 7] */,
+ 0x03234000 /* 00000c8d - 00000c8d [ 1] */,
+ 0x03244000 /* 00000c91 - 00000c91 [ 1] */,
+ 0x032a4000 /* 00000ca9 - 00000ca9 [ 1] */,
+ 0x032d0000 /* 00000cb4 - 00000cb4 [ 1] */,
+ 0x032e8001 /* 00000cba - 00000cbb [ 2] */,
+ 0x03314000 /* 00000cc5 - 00000cc5 [ 1] */,
+ 0x03324000 /* 00000cc9 - 00000cc9 [ 1] */,
+ 0x03338006 /* 00000cce - 00000cd4 [ 7] */,
+ 0x0335c005 /* 00000cd7 - 00000cdc [ 6] */,
+ 0x0337c000 /* 00000cdf - 00000cdf [ 1] */,
+ 0x03390001 /* 00000ce4 - 00000ce5 [ 2] */,
+ 0x033c0000 /* 00000cf0 - 00000cf0 [ 1] */,
+ 0x033d000b /* 00000cf4 - 00000cff [ 12] */,
+ 0x03434000 /* 00000d0d - 00000d0d [ 1] */,
+ 0x03444000 /* 00000d11 - 00000d11 [ 1] */,
+ 0x03514000 /* 00000d45 - 00000d45 [ 1] */,
+ 0x03524000 /* 00000d49 - 00000d49 [ 1] */,
+ 0x03540003 /* 00000d50 - 00000d53 [ 4] */,
+ 0x03590001 /* 00000d64 - 00000d65 [ 2] */,
+ 0x03600000 /* 00000d80 - 00000d80 [ 1] */,
+ 0x03610000 /* 00000d84 - 00000d84 [ 1] */,
+ 0x0365c002 /* 00000d97 - 00000d99 [ 3] */,
+ 0x036c8000 /* 00000db2 - 00000db2 [ 1] */,
+ 0x036f0000 /* 00000dbc - 00000dbc [ 1] */,
+ 0x036f8001 /* 00000dbe - 00000dbf [ 2] */,
+ 0x0371c002 /* 00000dc7 - 00000dc9 [ 3] */,
+ 0x0372c003 /* 00000dcb - 00000dce [ 4] */,
+ 0x03754000 /* 00000dd5 - 00000dd5 [ 1] */,
+ 0x0375c000 /* 00000dd7 - 00000dd7 [ 1] */,
+ 0x03780005 /* 00000de0 - 00000de5 [ 6] */,
+ 0x037c0001 /* 00000df0 - 00000df1 [ 2] */,
+ 0x037d400b /* 00000df5 - 00000e00 [ 12] */,
+ 0x038ec003 /* 00000e3b - 00000e3e [ 4] */,
+ 0x03970024 /* 00000e5c - 00000e80 [ 37] */,
+ 0x03a0c000 /* 00000e83 - 00000e83 [ 1] */,
+ 0x03a14000 /* 00000e85 - 00000e85 [ 1] */,
+ 0x03a2c000 /* 00000e8b - 00000e8b [ 1] */,
+ 0x03a90000 /* 00000ea4 - 00000ea4 [ 1] */,
+ 0x03a98000 /* 00000ea6 - 00000ea6 [ 1] */,
+ 0x03af8001 /* 00000ebe - 00000ebf [ 2] */,
+ 0x03b14000 /* 00000ec5 - 00000ec5 [ 1] */,
+ 0x03b1c000 /* 00000ec7 - 00000ec7 [ 1] */,
+ 0x03b3c000 /* 00000ecf - 00000ecf [ 1] */,
+ 0x03b68001 /* 00000eda - 00000edb [ 2] */,
+ 0x03b8001f /* 00000ee0 - 00000eff [ 32] */,
+ 0x03d20000 /* 00000f48 - 00000f48 [ 1] */,
+ 0x03db4003 /* 00000f6d - 00000f70 [ 4] */,
+ 0x03e60000 /* 00000f98 - 00000f98 [ 1] */,
+ 0x03ef4000 /* 00000fbd - 00000fbd [ 1] */,
+ 0x03f34000 /* 00000fcd - 00000fcd [ 1] */,
+ 0x03f6c024 /* 00000fdb - 00000fff [ 37] */,
+ 0x04318000 /* 000010c6 - 000010c6 [ 1] */,
+ 0x04320004 /* 000010c8 - 000010cc [ 5] */,
+ 0x04338001 /* 000010ce - 000010cf [ 2] */,
+ 0x04924000 /* 00001249 - 00001249 [ 1] */,
+ 0x04938001 /* 0000124e - 0000124f [ 2] */,
+ 0x0495c000 /* 00001257 - 00001257 [ 1] */,
+ 0x04964000 /* 00001259 - 00001259 [ 1] */,
+ 0x04978001 /* 0000125e - 0000125f [ 2] */,
+ 0x04a24000 /* 00001289 - 00001289 [ 1] */,
+ 0x04a38001 /* 0000128e - 0000128f [ 2] */,
+ 0x04ac4000 /* 000012b1 - 000012b1 [ 1] */,
+ 0x04ad8001 /* 000012b6 - 000012b7 [ 2] */,
+ 0x04afc000 /* 000012bf - 000012bf [ 1] */,
+ 0x04b04000 /* 000012c1 - 000012c1 [ 1] */,
+ 0x04b18001 /* 000012c6 - 000012c7 [ 2] */,
+ 0x04b5c000 /* 000012d7 - 000012d7 [ 1] */,
+ 0x04c44000 /* 00001311 - 00001311 [ 1] */,
+ 0x04c58001 /* 00001316 - 00001317 [ 2] */,
+ 0x04d6c001 /* 0000135b - 0000135c [ 2] */,
+ 0x04df4002 /* 0000137d - 0000137f [ 3] */,
+ 0x04e68005 /* 0000139a - 0000139f [ 6] */,
+ 0x04fd8001 /* 000013f6 - 000013f7 [ 2] */,
+ 0x04ff8001 /* 000013fe - 000013ff [ 2] */,
+ 0x05a00000 /* 00001680 - 00001680 [ 1] */,
+ 0x05a74002 /* 0000169d - 0000169f [ 3] */,
+ 0x05be4006 /* 000016f9 - 000016ff [ 7] */,
+ 0x05c58008 /* 00001716 - 0000171e [ 9] */,
+ 0x05cdc008 /* 00001737 - 0000173f [ 9] */,
+ 0x05d5000b /* 00001754 - 0000175f [ 12] */,
+ 0x05db4000 /* 0000176d - 0000176d [ 1] */,
+ 0x05dc4000 /* 00001771 - 00001771 [ 1] */,
+ 0x05dd000b /* 00001774 - 0000177f [ 12] */,
+ 0x05f78001 /* 000017de - 000017df [ 2] */,
+ 0x05fa8005 /* 000017ea - 000017ef [ 6] */,
+ 0x05fe8005 /* 000017fa - 000017ff [ 6] */,
+ 0x06038000 /* 0000180e - 0000180e [ 1] */,
+ 0x06068005 /* 0000181a - 0000181f [ 6] */,
+ 0x061e4006 /* 00001879 - 0000187f [ 7] */,
+ 0x062ac004 /* 000018ab - 000018af [ 5] */,
+ 0x063d8009 /* 000018f6 - 000018ff [ 10] */,
+ 0x0647c000 /* 0000191f - 0000191f [ 1] */,
+ 0x064b0003 /* 0000192c - 0000192f [ 4] */,
+ 0x064f0003 /* 0000193c - 0000193f [ 4] */,
+ 0x06504002 /* 00001941 - 00001943 [ 3] */,
+ 0x065b8001 /* 0000196e - 0000196f [ 2] */,
+ 0x065d400a /* 00001975 - 0000197f [ 11] */,
+ 0x066b0003 /* 000019ac - 000019af [ 4] */,
+ 0x06728005 /* 000019ca - 000019cf [ 6] */,
+ 0x0676c002 /* 000019db - 000019dd [ 3] */,
+ 0x06870001 /* 00001a1c - 00001a1d [ 2] */,
+ 0x0697c000 /* 00001a5f - 00001a5f [ 1] */,
+ 0x069f4001 /* 00001a7d - 00001a7e [ 2] */,
+ 0x06a28005 /* 00001a8a - 00001a8f [ 6] */,
+ 0x06a68005 /* 00001a9a - 00001a9f [ 6] */,
+ 0x06ab8001 /* 00001aae - 00001aaf [ 2] */,
+ 0x06b3c030 /* 00001acf - 00001aff [ 49] */,
+ 0x06d34002 /* 00001b4d - 00001b4f [ 3] */,
+ 0x06dfc000 /* 00001b7f - 00001b7f [ 1] */,
+ 0x06fd0007 /* 00001bf4 - 00001bfb [ 8] */,
+ 0x070e0002 /* 00001c38 - 00001c3a [ 3] */,
+ 0x07128002 /* 00001c4a - 00001c4c [ 3] */,
+ 0x07224006 /* 00001c89 - 00001c8f [ 7] */,
+ 0x072ec001 /* 00001cbb - 00001cbc [ 2] */,
+ 0x07320007 /* 00001cc8 - 00001ccf [ 8] */,
+ 0x073ec004 /* 00001cfb - 00001cff [ 5] */,
+ 0x07c58001 /* 00001f16 - 00001f17 [ 2] */,
+ 0x07c78001 /* 00001f1e - 00001f1f [ 2] */,
+ 0x07d18001 /* 00001f46 - 00001f47 [ 2] */,
+ 0x07d38001 /* 00001f4e - 00001f4f [ 2] */,
+ 0x07d60000 /* 00001f58 - 00001f58 [ 1] */,
+ 0x07d68000 /* 00001f5a - 00001f5a [ 1] */,
+ 0x07d70000 /* 00001f5c - 00001f5c [ 1] */,
+ 0x07d78000 /* 00001f5e - 00001f5e [ 1] */,
+ 0x07df8001 /* 00001f7e - 00001f7f [ 2] */,
+ 0x07ed4000 /* 00001fb5 - 00001fb5 [ 1] */,
+ 0x07f14000 /* 00001fc5 - 00001fc5 [ 1] */,
+ 0x07f50001 /* 00001fd4 - 00001fd5 [ 2] */,
+ 0x07f70000 /* 00001fdc - 00001fdc [ 1] */,
+ 0x07fc0001 /* 00001ff0 - 00001ff1 [ 2] */,
+ 0x07fd4000 /* 00001ff5 - 00001ff5 [ 1] */,
+ 0x07ffc010 /* 00001fff - 0000200f [ 17] */,
+ 0x080a0007 /* 00002028 - 0000202f [ 8] */,
+ 0x0817c010 /* 0000205f - 0000206f [ 17] */,
+ 0x081c8001 /* 00002072 - 00002073 [ 2] */,
+ 0x0823c000 /* 0000208f - 0000208f [ 1] */,
+ 0x08274002 /* 0000209d - 0000209f [ 3] */,
+ 0x0830400e /* 000020c1 - 000020cf [ 15] */,
+ 0x083c400e /* 000020f1 - 000020ff [ 15] */,
+ 0x08630003 /* 0000218c - 0000218f [ 4] */,
+ 0x0909c018 /* 00002427 - 0000243f [ 25] */,
+ 0x0912c014 /* 0000244b - 0000245f [ 21] */,
+ 0x0add0001 /* 00002b74 - 00002b75 [ 2] */,
+ 0x0ae58000 /* 00002b96 - 00002b96 [ 1] */,
+ 0x0b3d0004 /* 00002cf4 - 00002cf8 [ 5] */,
+ 0x0b498000 /* 00002d26 - 00002d26 [ 1] */,
+ 0x0b4a0004 /* 00002d28 - 00002d2c [ 5] */,
+ 0x0b4b8001 /* 00002d2e - 00002d2f [ 2] */,
+ 0x0b5a0006 /* 00002d68 - 00002d6e [ 7] */,
+ 0x0b5c400d /* 00002d71 - 00002d7e [ 14] */,
+ 0x0b65c008 /* 00002d97 - 00002d9f [ 9] */,
+ 0x0b69c000 /* 00002da7 - 00002da7 [ 1] */,
+ 0x0b6bc000 /* 00002daf - 00002daf [ 1] */,
+ 0x0b6dc000 /* 00002db7 - 00002db7 [ 1] */,
+ 0x0b6fc000 /* 00002dbf - 00002dbf [ 1] */,
+ 0x0b71c000 /* 00002dc7 - 00002dc7 [ 1] */,
+ 0x0b73c000 /* 00002dcf - 00002dcf [ 1] */,
+ 0x0b75c000 /* 00002dd7 - 00002dd7 [ 1] */,
+ 0x0b77c000 /* 00002ddf - 00002ddf [ 1] */,
+ 0x0b978021 /* 00002e5e - 00002e7f [ 34] */,
+ 0x0ba68000 /* 00002e9a - 00002e9a [ 1] */,
+ 0x0bbd000b /* 00002ef4 - 00002eff [ 12] */,
+ 0x0bf58019 /* 00002fd6 - 00002fef [ 26] */,
+ 0x0c000000 /* 00003000 - 00003000 [ 1] */,
+ 0x0c100000 /* 00003040 - 00003040 [ 1] */,
+ 0x0c25c001 /* 00003097 - 00003098 [ 2] */,
+ 0x0c400004 /* 00003100 - 00003104 [ 5] */,
+ 0x0c4c0000 /* 00003130 - 00003130 [ 1] */,
+ 0x0c63c000 /* 0000318f - 0000318f [ 1] */,
+ 0x0c79000a /* 000031e4 - 000031ee [ 11] */,
+ 0x0c87c000 /* 0000321f - 0000321f [ 1] */,
+ 0x29234002 /* 0000a48d - 0000a48f [ 3] */,
+ 0x2931c008 /* 0000a4c7 - 0000a4cf [ 9] */,
+ 0x298b0013 /* 0000a62c - 0000a63f [ 20] */,
+ 0x29be0007 /* 0000a6f8 - 0000a6ff [ 8] */,
+ 0x29f2c004 /* 0000a7cb - 0000a7cf [ 5] */,
+ 0x29f48000 /* 0000a7d2 - 0000a7d2 [ 1] */,
+ 0x29f50000 /* 0000a7d4 - 0000a7d4 [ 1] */,
+ 0x29f68017 /* 0000a7da - 0000a7f1 [ 24] */,
+ 0x2a0b4002 /* 0000a82d - 0000a82f [ 3] */,
+ 0x2a0e8005 /* 0000a83a - 0000a83f [ 6] */,
+ 0x2a1e0007 /* 0000a878 - 0000a87f [ 8] */,
+ 0x2a318007 /* 0000a8c6 - 0000a8cd [ 8] */,
+ 0x2a368005 /* 0000a8da - 0000a8df [ 6] */,
+ 0x2a55000a /* 0000a954 - 0000a95e [ 11] */,
+ 0x2a5f4002 /* 0000a97d - 0000a97f [ 3] */,
+ 0x2a738000 /* 0000a9ce - 0000a9ce [ 1] */,
+ 0x2a768003 /* 0000a9da - 0000a9dd [ 4] */,
+ 0x2a7fc000 /* 0000a9ff - 0000a9ff [ 1] */,
+ 0x2a8dc008 /* 0000aa37 - 0000aa3f [ 9] */,
+ 0x2a938001 /* 0000aa4e - 0000aa4f [ 2] */,
+ 0x2a968001 /* 0000aa5a - 0000aa5b [ 2] */,
+ 0x2ab0c017 /* 0000aac3 - 0000aada [ 24] */,
+ 0x2abdc009 /* 0000aaf7 - 0000ab00 [ 10] */,
+ 0x2ac1c001 /* 0000ab07 - 0000ab08 [ 2] */,
+ 0x2ac3c001 /* 0000ab0f - 0000ab10 [ 2] */,
+ 0x2ac5c008 /* 0000ab17 - 0000ab1f [ 9] */,
+ 0x2ac9c000 /* 0000ab27 - 0000ab27 [ 1] */,
+ 0x2acbc000 /* 0000ab2f - 0000ab2f [ 1] */,
+ 0x2adb0003 /* 0000ab6c - 0000ab6f [ 4] */,
+ 0x2afb8001 /* 0000abee - 0000abef [ 2] */,
+ 0x2afe8005 /* 0000abfa - 0000abff [ 6] */,
+ 0x35e9000b /* 0000d7a4 - 0000d7af [ 12] */,
+ 0x35f1c003 /* 0000d7c7 - 0000d7ca [ 4] */,
+ 0x35ff2103 /* 0000d7fc - 0000f8ff [ 8452] */,
+ 0x3e9b8001 /* 0000fa6e - 0000fa6f [ 2] */,
+ 0x3eb68025 /* 0000fada - 0000faff [ 38] */,
+ 0x3ec1c00b /* 0000fb07 - 0000fb12 [ 12] */,
+ 0x3ec60004 /* 0000fb18 - 0000fb1c [ 5] */,
+ 0x3ecdc000 /* 0000fb37 - 0000fb37 [ 1] */,
+ 0x3ecf4000 /* 0000fb3d - 0000fb3d [ 1] */,
+ 0x3ecfc000 /* 0000fb3f - 0000fb3f [ 1] */,
+ 0x3ed08000 /* 0000fb42 - 0000fb42 [ 1] */,
+ 0x3ed14000 /* 0000fb45 - 0000fb45 [ 1] */,
+ 0x3ef0c00f /* 0000fbc3 - 0000fbd2 [ 16] */,
+ 0x3f640001 /* 0000fd90 - 0000fd91 [ 2] */,
+ 0x3f720006 /* 0000fdc8 - 0000fdce [ 7] */,
+ 0x3f74001f /* 0000fdd0 - 0000fdef [ 32] */,
+ 0x3f868005 /* 0000fe1a - 0000fe1f [ 6] */,
+ 0x3f94c000 /* 0000fe53 - 0000fe53 [ 1] */,
+ 0x3f99c000 /* 0000fe67 - 0000fe67 [ 1] */,
+ 0x3f9b0003 /* 0000fe6c - 0000fe6f [ 4] */,
+ 0x3f9d4000 /* 0000fe75 - 0000fe75 [ 1] */,
+ 0x3fbf4003 /* 0000fefd - 0000ff00 [ 4] */,
+ 0x3fefc002 /* 0000ffbf - 0000ffc1 [ 3] */,
+ 0x3ff20001 /* 0000ffc8 - 0000ffc9 [ 2] */,
+ 0x3ff40001 /* 0000ffd0 - 0000ffd1 [ 2] */,
+ 0x3ff60001 /* 0000ffd8 - 0000ffd9 [ 2] */,
+ 0x3ff74002 /* 0000ffdd - 0000ffdf [ 3] */,
+ 0x3ff9c000 /* 0000ffe7 - 0000ffe7 [ 1] */,
+ 0x3ffbc00c /* 0000ffef - 0000fffb [ 13] */,
+ 0x3fff8001 /* 0000fffe - 0000ffff [ 2] */,
+ 0x40030000 /* 0001000c - 0001000c [ 1] */,
+ 0x4009c000 /* 00010027 - 00010027 [ 1] */,
+ 0x400ec000 /* 0001003b - 0001003b [ 1] */,
+ 0x400f8000 /* 0001003e - 0001003e [ 1] */,
+ 0x40138001 /* 0001004e - 0001004f [ 2] */,
+ 0x40178021 /* 0001005e - 0001007f [ 34] */,
+ 0x403ec004 /* 000100fb - 000100ff [ 5] */,
+ 0x4040c003 /* 00010103 - 00010106 [ 4] */,
+ 0x404d0002 /* 00010134 - 00010136 [ 3] */,
+ 0x4063c000 /* 0001018f - 0001018f [ 1] */,
+ 0x40674002 /* 0001019d - 0001019f [ 3] */,
+ 0x4068402e /* 000101a1 - 000101cf [ 47] */,
+ 0x407f8081 /* 000101fe - 0001027f [ 130] */,
+ 0x40a74002 /* 0001029d - 0001029f [ 3] */,
+ 0x40b4400e /* 000102d1 - 000102df [ 15] */,
+ 0x40bf0003 /* 000102fc - 000102ff [ 4] */,
+ 0x40c90008 /* 00010324 - 0001032c [ 9] */,
+ 0x40d2c004 /* 0001034b - 0001034f [ 5] */,
+ 0x40dec004 /* 0001037b - 0001037f [ 5] */,
+ 0x40e78000 /* 0001039e - 0001039e [ 1] */,
+ 0x40f10003 /* 000103c4 - 000103c7 [ 4] */,
+ 0x40f58029 /* 000103d6 - 000103ff [ 42] */,
+ 0x41278001 /* 0001049e - 0001049f [ 2] */,
+ 0x412a8005 /* 000104aa - 000104af [ 6] */,
+ 0x41350003 /* 000104d4 - 000104d7 [ 4] */,
+ 0x413f0003 /* 000104fc - 000104ff [ 4] */,
+ 0x414a0007 /* 00010528 - 0001052f [ 8] */,
+ 0x4159000a /* 00010564 - 0001056e [ 11] */,
+ 0x415ec000 /* 0001057b - 0001057b [ 1] */,
+ 0x4162c000 /* 0001058b - 0001058b [ 1] */,
+ 0x4164c000 /* 00010593 - 00010593 [ 1] */,
+ 0x41658000 /* 00010596 - 00010596 [ 1] */,
+ 0x41688000 /* 000105a2 - 000105a2 [ 1] */,
+ 0x416c8000 /* 000105b2 - 000105b2 [ 1] */,
+ 0x416e8000 /* 000105ba - 000105ba [ 1] */,
+ 0x416f4042 /* 000105bd - 000105ff [ 67] */,
+ 0x41cdc008 /* 00010737 - 0001073f [ 9] */,
+ 0x41d58009 /* 00010756 - 0001075f [ 10] */,
+ 0x41da0017 /* 00010768 - 0001077f [ 24] */,
+ 0x41e18000 /* 00010786 - 00010786 [ 1] */,
+ 0x41ec4000 /* 000107b1 - 000107b1 [ 1] */,
+ 0x41eec044 /* 000107bb - 000107ff [ 69] */,
+ 0x42018001 /* 00010806 - 00010807 [ 2] */,
+ 0x42024000 /* 00010809 - 00010809 [ 1] */,
+ 0x420d8000 /* 00010836 - 00010836 [ 1] */,
+ 0x420e4002 /* 00010839 - 0001083b [ 3] */,
+ 0x420f4001 /* 0001083d - 0001083e [ 2] */,
+ 0x42158000 /* 00010856 - 00010856 [ 1] */,
+ 0x4227c007 /* 0001089f - 000108a6 [ 8] */,
+ 0x422c002f /* 000108b0 - 000108df [ 48] */,
+ 0x423cc000 /* 000108f3 - 000108f3 [ 1] */,
+ 0x423d8004 /* 000108f6 - 000108fa [ 5] */,
+ 0x42470002 /* 0001091c - 0001091e [ 3] */,
+ 0x424e8004 /* 0001093a - 0001093e [ 5] */,
+ 0x4250003f /* 00010940 - 0001097f [ 64] */,
+ 0x426e0003 /* 000109b8 - 000109bb [ 4] */,
+ 0x42740001 /* 000109d0 - 000109d1 [ 2] */,
+ 0x42810000 /* 00010a04 - 00010a04 [ 1] */,
+ 0x4281c004 /* 00010a07 - 00010a0b [ 5] */,
+ 0x42850000 /* 00010a14 - 00010a14 [ 1] */,
+ 0x42860000 /* 00010a18 - 00010a18 [ 1] */,
+ 0x428d8001 /* 00010a36 - 00010a37 [ 2] */,
+ 0x428ec003 /* 00010a3b - 00010a3e [ 4] */,
+ 0x42924006 /* 00010a49 - 00010a4f [ 7] */,
+ 0x42964006 /* 00010a59 - 00010a5f [ 7] */,
+ 0x42a8001f /* 00010aa0 - 00010abf [ 32] */,
+ 0x42b9c003 /* 00010ae7 - 00010aea [ 4] */,
+ 0x42bdc008 /* 00010af7 - 00010aff [ 9] */,
+ 0x42cd8002 /* 00010b36 - 00010b38 [ 3] */,
+ 0x42d58001 /* 00010b56 - 00010b57 [ 2] */,
+ 0x42dcc004 /* 00010b73 - 00010b77 [ 5] */,
+ 0x42e48006 /* 00010b92 - 00010b98 [ 7] */,
+ 0x42e7400b /* 00010b9d - 00010ba8 [ 12] */,
+ 0x42ec004f /* 00010bb0 - 00010bff [ 80] */,
+ 0x43124036 /* 00010c49 - 00010c7f [ 55] */,
+ 0x432cc00c /* 00010cb3 - 00010cbf [ 13] */,
+ 0x433cc006 /* 00010cf3 - 00010cf9 [ 7] */,
+ 0x434a0007 /* 00010d28 - 00010d2f [ 8] */,
+ 0x434e8125 /* 00010d3a - 00010e5f [ 294] */,
+ 0x439fc000 /* 00010e7f - 00010e7f [ 1] */,
+ 0x43aa8000 /* 00010eaa - 00010eaa [ 1] */,
+ 0x43ab8001 /* 00010eae - 00010eaf [ 2] */,
+ 0x43ac804a /* 00010eb2 - 00010efc [ 75] */,
+ 0x43ca0007 /* 00010f28 - 00010f2f [ 8] */,
+ 0x43d68015 /* 00010f5a - 00010f6f [ 22] */,
+ 0x43e28025 /* 00010f8a - 00010faf [ 38] */,
+ 0x43f30013 /* 00010fcc - 00010fdf [ 20] */,
+ 0x43fdc008 /* 00010ff7 - 00010fff [ 9] */,
+ 0x44138003 /* 0001104e - 00011051 [ 4] */,
+ 0x441d8008 /* 00011076 - 0001107e [ 9] */,
+ 0x442f4000 /* 000110bd - 000110bd [ 1] */,
+ 0x4430c00c /* 000110c3 - 000110cf [ 13] */,
+ 0x443a4006 /* 000110e9 - 000110ef [ 7] */,
+ 0x443e8005 /* 000110fa - 000110ff [ 6] */,
+ 0x444d4000 /* 00011135 - 00011135 [ 1] */,
+ 0x44520007 /* 00011148 - 0001114f [ 8] */,
+ 0x445dc008 /* 00011177 - 0001117f [ 9] */,
+ 0x44780000 /* 000111e0 - 000111e0 [ 1] */,
+ 0x447d400a /* 000111f5 - 000111ff [ 11] */,
+ 0x44848000 /* 00011212 - 00011212 [ 1] */,
+ 0x4490803d /* 00011242 - 0001127f [ 62] */,
+ 0x44a1c000 /* 00011287 - 00011287 [ 1] */,
+ 0x44a24000 /* 00011289 - 00011289 [ 1] */,
+ 0x44a38000 /* 0001128e - 0001128e [ 1] */,
+ 0x44a78000 /* 0001129e - 0001129e [ 1] */,
+ 0x44aa8005 /* 000112aa - 000112af [ 6] */,
+ 0x44bac004 /* 000112eb - 000112ef [ 5] */,
+ 0x44be8005 /* 000112fa - 000112ff [ 6] */,
+ 0x44c10000 /* 00011304 - 00011304 [ 1] */,
+ 0x44c34001 /* 0001130d - 0001130e [ 2] */,
+ 0x44c44001 /* 00011311 - 00011312 [ 2] */,
+ 0x44ca4000 /* 00011329 - 00011329 [ 1] */,
+ 0x44cc4000 /* 00011331 - 00011331 [ 1] */,
+ 0x44cd0000 /* 00011334 - 00011334 [ 1] */,
+ 0x44ce8000 /* 0001133a - 0001133a [ 1] */,
+ 0x44d14001 /* 00011345 - 00011346 [ 2] */,
+ 0x44d24001 /* 00011349 - 0001134a [ 2] */,
+ 0x44d38001 /* 0001134e - 0001134f [ 2] */,
+ 0x44d44005 /* 00011351 - 00011356 [ 6] */,
+ 0x44d60004 /* 00011358 - 0001135c [ 5] */,
+ 0x44d90001 /* 00011364 - 00011365 [ 2] */,
+ 0x44db4002 /* 0001136d - 0001136f [ 3] */,
+ 0x44dd408a /* 00011375 - 000113ff [ 139] */,
+ 0x45170000 /* 0001145c - 0001145c [ 1] */,
+ 0x4518801d /* 00011462 - 0001147f [ 30] */,
+ 0x45320007 /* 000114c8 - 000114cf [ 8] */,
+ 0x453680a5 /* 000114da - 0001157f [ 166] */,
+ 0x456d8001 /* 000115b6 - 000115b7 [ 2] */,
+ 0x45778021 /* 000115de - 000115ff [ 34] */,
+ 0x4591400a /* 00011645 - 0001164f [ 11] */,
+ 0x45968005 /* 0001165a - 0001165f [ 6] */,
+ 0x459b4012 /* 0001166d - 0001167f [ 19] */,
+ 0x45ae8005 /* 000116ba - 000116bf [ 6] */,
+ 0x45b28035 /* 000116ca - 000116ff [ 54] */,
+ 0x45c6c001 /* 0001171b - 0001171c [ 2] */,
+ 0x45cb0003 /* 0001172c - 0001172f [ 4] */,
+ 0x45d1c0b8 /* 00011747 - 000117ff [ 185] */,
+ 0x460f0063 /* 0001183c - 0001189f [ 100] */,
+ 0x463cc00b /* 000118f3 - 000118fe [ 12] */,
+ 0x4641c001 /* 00011907 - 00011908 [ 2] */,
+ 0x46428001 /* 0001190a - 0001190b [ 2] */,
+ 0x46450000 /* 00011914 - 00011914 [ 1] */,
+ 0x4645c000 /* 00011917 - 00011917 [ 1] */,
+ 0x464d8000 /* 00011936 - 00011936 [ 1] */,
+ 0x464e4001 /* 00011939 - 0001193a [ 2] */,
+ 0x4651c008 /* 00011947 - 0001194f [ 9] */,
+ 0x46568045 /* 0001195a - 0001199f [ 70] */,
+ 0x466a0001 /* 000119a8 - 000119a9 [ 2] */,
+ 0x46760001 /* 000119d8 - 000119d9 [ 2] */,
+ 0x4679401a /* 000119e5 - 000119ff [ 27] */,
+ 0x46920007 /* 00011a48 - 00011a4f [ 8] */,
+ 0x46a8c00c /* 00011aa3 - 00011aaf [ 13] */,
+ 0x46be4006 /* 00011af9 - 00011aff [ 7] */,
+ 0x46c280f5 /* 00011b0a - 00011bff [ 246] */,
+ 0x47024000 /* 00011c09 - 00011c09 [ 1] */,
+ 0x470dc000 /* 00011c37 - 00011c37 [ 1] */,
+ 0x47118009 /* 00011c46 - 00011c4f [ 10] */,
+ 0x471b4002 /* 00011c6d - 00011c6f [ 3] */,
+ 0x47240001 /* 00011c90 - 00011c91 [ 2] */,
+ 0x472a0000 /* 00011ca8 - 00011ca8 [ 1] */,
+ 0x472dc048 /* 00011cb7 - 00011cff [ 73] */,
+ 0x4741c000 /* 00011d07 - 00011d07 [ 1] */,
+ 0x47428000 /* 00011d0a - 00011d0a [ 1] */,
+ 0x474dc002 /* 00011d37 - 00011d39 [ 3] */,
+ 0x474ec000 /* 00011d3b - 00011d3b [ 1] */,
+ 0x474f8000 /* 00011d3e - 00011d3e [ 1] */,
+ 0x47520007 /* 00011d48 - 00011d4f [ 8] */,
+ 0x47568005 /* 00011d5a - 00011d5f [ 6] */,
+ 0x47598000 /* 00011d66 - 00011d66 [ 1] */,
+ 0x475a4000 /* 00011d69 - 00011d69 [ 1] */,
+ 0x4763c000 /* 00011d8f - 00011d8f [ 1] */,
+ 0x47648000 /* 00011d92 - 00011d92 [ 1] */,
+ 0x47664006 /* 00011d99 - 00011d9f [ 7] */,
+ 0x476a8135 /* 00011daa - 00011edf [ 310] */,
+ 0x47be4006 /* 00011ef9 - 00011eff [ 7] */,
+ 0x47c44000 /* 00011f11 - 00011f11 [ 1] */,
+ 0x47cec002 /* 00011f3b - 00011f3d [ 3] */,
+ 0x47d68055 /* 00011f5a - 00011faf [ 86] */,
+ 0x47ec400e /* 00011fb1 - 00011fbf [ 15] */,
+ 0x47fc800c /* 00011ff2 - 00011ffe [ 13] */,
+ 0x48e68065 /* 0001239a - 000123ff [ 102] */,
+ 0x491bc000 /* 0001246f - 0001246f [ 1] */,
+ 0x491d400a /* 00012475 - 0001247f [ 11] */,
+ 0x49510a4b /* 00012544 - 00012f8f [ 2636] */,
+ 0x4bfcc00c /* 00012ff3 - 00012fff [ 13] */,
+ 0x4d0c000f /* 00013430 - 0001343f [ 16] */,
+ 0x4d158fa9 /* 00013456 - 000143ff [ 4010] */,
+ 0x5191e1b8 /* 00014647 - 000167ff [ 8633] */,
+ 0x5a8e4006 /* 00016a39 - 00016a3f [ 7] */,
+ 0x5a97c000 /* 00016a5f - 00016a5f [ 1] */,
+ 0x5a9a8003 /* 00016a6a - 00016a6d [ 4] */,
+ 0x5aafc000 /* 00016abf - 00016abf [ 1] */,
+ 0x5ab28005 /* 00016aca - 00016acf [ 6] */,
+ 0x5abb8001 /* 00016aee - 00016aef [ 2] */,
+ 0x5abd8009 /* 00016af6 - 00016aff [ 10] */,
+ 0x5ad18009 /* 00016b46 - 00016b4f [ 10] */,
+ 0x5ad68000 /* 00016b5a - 00016b5a [ 1] */,
+ 0x5ad88000 /* 00016b62 - 00016b62 [ 1] */,
+ 0x5ade0004 /* 00016b78 - 00016b7c [ 5] */,
+ 0x5ae402af /* 00016b90 - 00016e3f [ 688] */,
+ 0x5ba6c064 /* 00016e9b - 00016eff [ 101] */,
+ 0x5bd2c003 /* 00016f4b - 00016f4e [ 4] */,
+ 0x5be20006 /* 00016f88 - 00016f8e [ 7] */,
+ 0x5be8003f /* 00016fa0 - 00016fdf [ 64] */,
+ 0x5bf9400a /* 00016fe5 - 00016fef [ 11] */,
+ 0x5bfc800d /* 00016ff2 - 00016fff [ 14] */,
+ 0x61fe0007 /* 000187f8 - 000187ff [ 8] */,
+ 0x63358029 /* 00018cd6 - 00018cff [ 42] */,
+ 0x634262e6 /* 00018d09 - 0001afef [ 8935] */,
+ 0x6bfd0000 /* 0001aff4 - 0001aff4 [ 1] */,
+ 0x6bff0000 /* 0001affc - 0001affc [ 1] */,
+ 0x6bffc000 /* 0001afff - 0001afff [ 1] */,
+ 0x6c48c00e /* 0001b123 - 0001b131 [ 15] */,
+ 0x6c4cc01c /* 0001b133 - 0001b14f [ 29] */,
+ 0x6c54c001 /* 0001b153 - 0001b154 [ 2] */,
+ 0x6c55800d /* 0001b156 - 0001b163 [ 14] */,
+ 0x6c5a0007 /* 0001b168 - 0001b16f [ 8] */,
+ 0x6cbf0903 /* 0001b2fc - 0001bbff [ 2308] */,
+ 0x6f1ac004 /* 0001bc6b - 0001bc6f [ 5] */,
+ 0x6f1f4002 /* 0001bc7d - 0001bc7f [ 3] */,
+ 0x6f224006 /* 0001bc89 - 0001bc8f [ 7] */,
+ 0x6f268001 /* 0001bc9a - 0001bc9b [ 2] */,
+ 0x6f28125f /* 0001bca0 - 0001ceff [ 4704] */,
+ 0x73cb8001 /* 0001cf2e - 0001cf2f [ 2] */,
+ 0x73d1c008 /* 0001cf47 - 0001cf4f [ 9] */,
+ 0x73f1003b /* 0001cfc4 - 0001cfff [ 60] */,
+ 0x743d8009 /* 0001d0f6 - 0001d0ff [ 10] */,
+ 0x7449c001 /* 0001d127 - 0001d128 [ 2] */,
+ 0x745cc007 /* 0001d173 - 0001d17a [ 8] */,
+ 0x747ac014 /* 0001d1eb - 0001d1ff [ 21] */,
+ 0x74918079 /* 0001d246 - 0001d2bf [ 122] */,
+ 0x74b5000b /* 0001d2d4 - 0001d2df [ 12] */,
+ 0x74bd000b /* 0001d2f4 - 0001d2ff [ 12] */,
+ 0x74d5c008 /* 0001d357 - 0001d35f [ 9] */,
+ 0x74de4086 /* 0001d379 - 0001d3ff [ 135] */,
+ 0x75154000 /* 0001d455 - 0001d455 [ 1] */,
+ 0x75274000 /* 0001d49d - 0001d49d [ 1] */,
+ 0x75280001 /* 0001d4a0 - 0001d4a1 [ 2] */,
+ 0x7528c001 /* 0001d4a3 - 0001d4a4 [ 2] */,
+ 0x7529c001 /* 0001d4a7 - 0001d4a8 [ 2] */,
+ 0x752b4000 /* 0001d4ad - 0001d4ad [ 1] */,
+ 0x752e8000 /* 0001d4ba - 0001d4ba [ 1] */,
+ 0x752f0000 /* 0001d4bc - 0001d4bc [ 1] */,
+ 0x75310000 /* 0001d4c4 - 0001d4c4 [ 1] */,
+ 0x75418000 /* 0001d506 - 0001d506 [ 1] */,
+ 0x7542c001 /* 0001d50b - 0001d50c [ 2] */,
+ 0x75454000 /* 0001d515 - 0001d515 [ 1] */,
+ 0x75474000 /* 0001d51d - 0001d51d [ 1] */,
+ 0x754e8000 /* 0001d53a - 0001d53a [ 1] */,
+ 0x754fc000 /* 0001d53f - 0001d53f [ 1] */,
+ 0x75514000 /* 0001d545 - 0001d545 [ 1] */,
+ 0x7551c002 /* 0001d547 - 0001d549 [ 3] */,
+ 0x75544000 /* 0001d551 - 0001d551 [ 1] */,
+ 0x75a98001 /* 0001d6a6 - 0001d6a7 [ 2] */,
+ 0x75f30001 /* 0001d7cc - 0001d7cd [ 2] */,
+ 0x76a3000e /* 0001da8c - 0001da9a [ 15] */,
+ 0x76a80000 /* 0001daa0 - 0001daa0 [ 1] */,
+ 0x76ac044f /* 0001dab0 - 0001deff [ 1104] */,
+ 0x77c7c005 /* 0001df1f - 0001df24 [ 6] */,
+ 0x77cac0d4 /* 0001df2b - 0001dfff [ 213] */,
+ 0x7801c000 /* 0001e007 - 0001e007 [ 1] */,
+ 0x78064001 /* 0001e019 - 0001e01a [ 2] */,
+ 0x78088000 /* 0001e022 - 0001e022 [ 1] */,
+ 0x78094000 /* 0001e025 - 0001e025 [ 1] */,
+ 0x780ac004 /* 0001e02b - 0001e02f [ 5] */,
+ 0x781b8020 /* 0001e06e - 0001e08e [ 33] */,
+ 0x7824006f /* 0001e090 - 0001e0ff [ 112] */,
+ 0x784b4002 /* 0001e12d - 0001e12f [ 3] */,
+ 0x784f8001 /* 0001e13e - 0001e13f [ 2] */,
+ 0x78528003 /* 0001e14a - 0001e14d [ 4] */,
+ 0x7854013f /* 0001e150 - 0001e28f [ 320] */,
+ 0x78abc010 /* 0001e2af - 0001e2bf [ 17] */,
+ 0x78be8004 /* 0001e2fa - 0001e2fe [ 5] */,
+ 0x78c001cf /* 0001e300 - 0001e4cf [ 464] */,
+ 0x793e82e5 /* 0001e4fa - 0001e7df [ 742] */,
+ 0x79f9c000 /* 0001e7e7 - 0001e7e7 [ 1] */,
+ 0x79fb0000 /* 0001e7ec - 0001e7ec [ 1] */,
+ 0x79fbc000 /* 0001e7ef - 0001e7ef [ 1] */,
+ 0x79ffc000 /* 0001e7ff - 0001e7ff [ 1] */,
+ 0x7a314001 /* 0001e8c5 - 0001e8c6 [ 2] */,
+ 0x7a35c028 /* 0001e8d7 - 0001e8ff [ 41] */,
+ 0x7a530003 /* 0001e94c - 0001e94f [ 4] */,
+ 0x7a568003 /* 0001e95a - 0001e95d [ 4] */,
+ 0x7a580310 /* 0001e960 - 0001ec70 [ 785] */,
+ 0x7b2d404b /* 0001ecb5 - 0001ed00 [ 76] */,
+ 0x7b4f80c1 /* 0001ed3e - 0001edff [ 194] */,
+ 0x7b810000 /* 0001ee04 - 0001ee04 [ 1] */,
+ 0x7b880000 /* 0001ee20 - 0001ee20 [ 1] */,
+ 0x7b88c000 /* 0001ee23 - 0001ee23 [ 1] */,
+ 0x7b894001 /* 0001ee25 - 0001ee26 [ 2] */,
+ 0x7b8a0000 /* 0001ee28 - 0001ee28 [ 1] */,
+ 0x7b8cc000 /* 0001ee33 - 0001ee33 [ 1] */,
+ 0x7b8e0000 /* 0001ee38 - 0001ee38 [ 1] */,
+ 0x7b8e8000 /* 0001ee3a - 0001ee3a [ 1] */,
+ 0x7b8f0005 /* 0001ee3c - 0001ee41 [ 6] */,
+ 0x7b90c003 /* 0001ee43 - 0001ee46 [ 4] */,
+ 0x7b920000 /* 0001ee48 - 0001ee48 [ 1] */,
+ 0x7b928000 /* 0001ee4a - 0001ee4a [ 1] */,
+ 0x7b930000 /* 0001ee4c - 0001ee4c [ 1] */,
+ 0x7b940000 /* 0001ee50 - 0001ee50 [ 1] */,
+ 0x7b94c000 /* 0001ee53 - 0001ee53 [ 1] */,
+ 0x7b954001 /* 0001ee55 - 0001ee56 [ 2] */,
+ 0x7b960000 /* 0001ee58 - 0001ee58 [ 1] */,
+ 0x7b968000 /* 0001ee5a - 0001ee5a [ 1] */,
+ 0x7b970000 /* 0001ee5c - 0001ee5c [ 1] */,
+ 0x7b978000 /* 0001ee5e - 0001ee5e [ 1] */,
+ 0x7b980000 /* 0001ee60 - 0001ee60 [ 1] */,
+ 0x7b98c000 /* 0001ee63 - 0001ee63 [ 1] */,
+ 0x7b994001 /* 0001ee65 - 0001ee66 [ 2] */,
+ 0x7b9ac000 /* 0001ee6b - 0001ee6b [ 1] */,
+ 0x7b9cc000 /* 0001ee73 - 0001ee73 [ 1] */,
+ 0x7b9e0000 /* 0001ee78 - 0001ee78 [ 1] */,
+ 0x7b9f4000 /* 0001ee7d - 0001ee7d [ 1] */,
+ 0x7b9fc000 /* 0001ee7f - 0001ee7f [ 1] */,
+ 0x7ba28000 /* 0001ee8a - 0001ee8a [ 1] */,
+ 0x7ba70004 /* 0001ee9c - 0001eea0 [ 5] */,
+ 0x7ba90000 /* 0001eea4 - 0001eea4 [ 1] */,
+ 0x7baa8000 /* 0001eeaa - 0001eeaa [ 1] */,
+ 0x7baf0033 /* 0001eebc - 0001eeef [ 52] */,
+ 0x7bbc810d /* 0001eef2 - 0001efff [ 270] */,
+ 0x7c0b0003 /* 0001f02c - 0001f02f [ 4] */,
+ 0x7c25000b /* 0001f094 - 0001f09f [ 12] */,
+ 0x7c2bc001 /* 0001f0af - 0001f0b0 [ 2] */,
+ 0x7c300000 /* 0001f0c0 - 0001f0c0 [ 1] */,
+ 0x7c340000 /* 0001f0d0 - 0001f0d0 [ 1] */,
+ 0x7c3d8009 /* 0001f0f6 - 0001f0ff [ 10] */,
+ 0x7c6b8037 /* 0001f1ae - 0001f1e5 [ 56] */,
+ 0x7c80c00c /* 0001f203 - 0001f20f [ 13] */,
+ 0x7c8f0003 /* 0001f23c - 0001f23f [ 4] */,
+ 0x7c924006 /* 0001f249 - 0001f24f [ 7] */,
+ 0x7c94800d /* 0001f252 - 0001f25f [ 14] */,
+ 0x7c998099 /* 0001f266 - 0001f2ff [ 154] */,
+ 0x7db60003 /* 0001f6d8 - 0001f6db [ 4] */,
+ 0x7dbb4002 /* 0001f6ed - 0001f6ef [ 3] */,
+ 0x7dbf4002 /* 0001f6fd - 0001f6ff [ 3] */,
+ 0x7dddc003 /* 0001f777 - 0001f77a [ 4] */,
+ 0x7df68005 /* 0001f7da - 0001f7df [ 6] */,
+ 0x7dfb0003 /* 0001f7ec - 0001f7ef [ 4] */,
+ 0x7dfc400e /* 0001f7f1 - 0001f7ff [ 15] */,
+ 0x7e030003 /* 0001f80c - 0001f80f [ 4] */,
+ 0x7e120007 /* 0001f848 - 0001f84f [ 8] */,
+ 0x7e168005 /* 0001f85a - 0001f85f [ 6] */,
+ 0x7e220007 /* 0001f888 - 0001f88f [ 8] */,
+ 0x7e2b8001 /* 0001f8ae - 0001f8af [ 2] */,
+ 0x7e2c804d /* 0001f8b2 - 0001f8ff [ 78] */,
+ 0x7e95000b /* 0001fa54 - 0001fa5f [ 12] */,
+ 0x7e9b8001 /* 0001fa6e - 0001fa6f [ 2] */,
+ 0x7e9f4002 /* 0001fa7d - 0001fa7f [ 3] */,
+ 0x7ea24006 /* 0001fa89 - 0001fa8f [ 7] */,
+ 0x7eaf8000 /* 0001fabe - 0001fabe [ 1] */,
+ 0x7eb18007 /* 0001fac6 - 0001facd [ 8] */,
+ 0x7eb70003 /* 0001fadc - 0001fadf [ 4] */,
+ 0x7eba4006 /* 0001fae9 - 0001faef [ 7] */,
+ 0x7ebe4006 /* 0001faf9 - 0001faff [ 7] */,
+ 0x7ee4c000 /* 0001fb93 - 0001fb93 [ 1] */,
+ 0x7ef2c024 /* 0001fbcb - 0001fbef [ 37] */,
+ 0x7efe8405 /* 0001fbfa - 0001ffff [ 1030] */,
+ 0xa9b8001f /* 0002a6e0 - 0002a6ff [ 32] */,
+ 0xadce8005 /* 0002b73a - 0002b73f [ 6] */,
+ 0xae078001 /* 0002b81e - 0002b81f [ 2] */,
+ 0xb3a8800d /* 0002cea2 - 0002ceaf [ 14] */,
+ 0xbaf8400e /* 0002ebe1 - 0002ebef [ 15] */,
+ 0xbb9789a1 /* 0002ee5e - 0002f7ff [ 2466] */,
+ 0xbe8785e1 /* 0002fa1e - 0002ffff [ 1506] */,
+ 0xc4d2c004 /* 0003134b - 0003134f [ 5] */};
+
+/// Returns whether the code unit needs to be escaped.
+///
+/// At the end of the valid Unicode code points space a lot of code points are
+/// either reserved or a noncharacter. Adding all these entries to the
+/// lookup table would greatly increase the size of the table. Instead these
+/// entries are manually processed. In this large area of reserved code points,
+/// there is a small area of extended graphemes that should not be escaped
+/// unconditionally. This is also manually coded. See the generation script for
+/// more details.
+
+///
+/// \\pre The code point is a valid Unicode code point.
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool __needs_escape(const char32_t __code_point) noexcept {
+
+ // The entries in the gap at the end.
+ if(__code_point >= 0x000e0100 && __code_point <= 0x000e01ef)
+ return false;
+
+ // The entries at the end.
+ if (__code_point >= 0x000323b0)
+ return true;
+
+ ptrdiff_t __i = std::ranges::upper_bound(__entries, (__code_point << 14) | 0x3fffu) - __entries;
+ if (__i == 0)
+ return false;
+
+ --__i;
+ uint32_t __upper_bound = (__entries[__i] >> 14) + (__entries[__i] & 0x3fffu);
+ return __code_point <= __upper_bound;
+}
+
+// clang-format on
+} // namespace __escaped_output_table
+
+#endif //_LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_ESCAPED_OUTPUT_TABLE_H
diff --git a/libcxx/include/__cxx03/__format/extended_grapheme_cluster_table.h b/libcxx/include/__cxx03/__format/extended_grapheme_cluster_table.h
new file mode 100644
index 00000000000000..48581d8a5dde3d
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/extended_grapheme_cluster_table.h
@@ -0,0 +1,1663 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// WARNING, this entire header is generated by
+// utils/generate_extended_grapheme_cluster_table.py
+// DO NOT MODIFY!
+
+// UNICODE, INC. LICENSE AGREEMENT - DATA FILES AND SOFTWARE
+//
+// See Terms of Use <https://www.unicode.org/copyright.html>
+// for definitions of Unicode Inc.'s Data Files and Software.
+//
+// NOTICE TO USER: Carefully read the following legal agreement.
+// BY DOWNLOADING, INSTALLING, COPYING OR OTHERWISE USING UNICODE INC.'S
+// DATA FILES ("DATA FILES"), AND/OR SOFTWARE ("SOFTWARE"),
+// YOU UNEQUIVOCALLY ACCEPT, AND AGREE TO BE BOUND BY, ALL OF THE
+// TERMS AND CONDITIONS OF THIS AGREEMENT.
+// IF YOU DO NOT AGREE, DO NOT DOWNLOAD, INSTALL, COPY, DISTRIBUTE OR USE
+// THE DATA FILES OR SOFTWARE.
+//
+// COPYRIGHT AND PERMISSION NOTICE
+//
+// Copyright (c) 1991-2022 Unicode, Inc. All rights reserved.
+// Distributed under the Terms of Use in https://www.unicode.org/copyright.html.
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of the Unicode data files and any associated documentation
+// (the "Data Files") or Unicode software and any associated documentation
+// (the "Software") to deal in the Data Files or Software
+// without restriction, including without limitation the rights to use,
+// copy, modify, merge, publish, distribute, and/or sell copies of
+// the Data Files or Software, and to permit persons to whom the Data Files
+// or Software are furnished to do so, provided that either
+// (a) this copyright and permission notice appear with all copies
+// of the Data Files or Software, or
+// (b) this copyright and permission notice appear in associated
+// Documentation.
+//
+// THE DATA FILES AND SOFTWARE ARE PROVIDED "AS IS", WITHOUT WARRANTY OF
+// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+// WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+// IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS
+// NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL
+// DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+// DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THE DATA FILES OR SOFTWARE.
+//
+// Except as contained in this notice, the name of a copyright holder
+// shall not be used in advertising or otherwise to promote the sale,
+// use or other dealings in these Data Files or Software without prior
+// written authorization of the copyright holder.
+
+#ifndef _LIBCPP___FORMAT_EXTENDED_GRAPHEME_CLUSTER_TABLE_H
+#define _LIBCPP___FORMAT_EXTENDED_GRAPHEME_CLUSTER_TABLE_H
+
+#include <__algorithm/ranges_upper_bound.h>
+#include <__config>
+#include <__iterator/access.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __extended_grapheme_custer_property_boundary {
+
+enum class __property : uint8_t {
+ // Values generated from the data files.
+ __CR,
+ __Control,
+ __Extend,
+ __Extended_Pictographic,
+ __L,
+ __LF,
+ __LV,
+ __LVT,
+ __Prepend,
+ __Regional_Indicator,
+ __SpacingMark,
+ __T,
+ __V,
+ __ZWJ,
+
+ // The properies below aren't stored in the "database".
+
+ // Text position properties.
+ __sot,
+ __eot,
+
+ // The code unit has none of above properties.
+ __none
+};
+
+/// The entries of the extended grapheme cluster bondary property table.
+///
+/// The data is generated from
+/// - https://www.unicode.org/Public/UCD/latest/ucd/auxiliary/GraphemeBreakProperty.txt
+/// - https://www.unicode.org/Public/UCD/latest/ucd/emoji/emoji-data.txt
+///
+/// The data has 3 values
+/// - bits [0, 3] The property. One of the values generated from the datafiles
+/// of \ref __property
+/// - bits [4, 10] The size of the range.
+/// - bits [11, 31] The lower bound code point of the range. The upper bound of
+/// the range is lower bound + size.
+///
+/// The 7 bits for the size allow a maximum range of 128 elements. Some ranges
+/// in the Unicode tables are larger. They are stored in multiple consecutive
+/// ranges in the data table. An alternative would be to store the sizes in a
+/// separate 16-bit value. The original MSVC STL code had such an approach, but
+/// this approach uses less space for the data and is about 4% faster in the
+/// following benchmark.
+/// libcxx/benchmarks/std_format_spec_string_unicode.bench.cpp
+// clang-format off
+_LIBCPP_HIDE_FROM_ABI inline constexpr uint32_t __entries[1496] = {
+ 0x00000091,
+ 0x00005005,
+ 0x00005811,
+ 0x00006800,
+ 0x00007111,
+ 0x0003fa01,
+ 0x00054803,
+ 0x00056801,
+ 0x00057003,
+ 0x001806f2,
+ 0x00241862,
+ 0x002c8ac2,
+ 0x002df802,
+ 0x002e0812,
+ 0x002e2012,
+ 0x002e3802,
+ 0x00300058,
+ 0x003080a2,
+ 0x0030e001,
+ 0x00325942,
+ 0x00338002,
+ 0x0036b062,
+ 0x0036e808,
+ 0x0036f852,
+ 0x00373812,
+ 0x00375032,
+ 0x00387808,
+ 0x00388802,
+ 0x003981a2,
+ 0x003d30a2,
+ 0x003f5882,
+ 0x003fe802,
+ 0x0040b032,
+ 0x0040d882,
+ 0x00412822,
+ 0x00414842,
+ 0x0042c822,
+ 0x00448018,
+ 0x0044c072,
+ 0x00465172,
+ 0x00471008,
+ 0x004719f2,
+ 0x0048180a,
+ 0x0049d002,
+ 0x0049d80a,
+ 0x0049e002,
+ 0x0049f02a,
+ 0x004a0872,
+ 0x004a483a,
+ 0x004a6802,
+ 0x004a701a,
+ 0x004a8862,
+ 0x004b1012,
+ 0x004c0802,
+ 0x004c101a,
+ 0x004de002,
+ 0x004df002,
+ 0x004df81a,
+ 0x004e0832,
+ 0x004e381a,
+ 0x004e581a,
+ 0x004e6802,
+ 0x004eb802,
+ 0x004f1012,
+ 0x004ff002,
+ 0x00500812,
+ 0x0050180a,
+ 0x0051e002,
+ 0x0051f02a,
+ 0x00520812,
+ 0x00523812,
+ 0x00525822,
+ 0x00528802,
+ 0x00538012,
+ 0x0053a802,
+ 0x00540812,
+ 0x0054180a,
+ 0x0055e002,
+ 0x0055f02a,
+ 0x00560842,
+ 0x00563812,
+ 0x0056480a,
+ 0x0056581a,
+ 0x00566802,
+ 0x00571012,
+ 0x0057d052,
+ 0x00580802,
+ 0x0058101a,
+ 0x0059e002,
+ 0x0059f012,
+ 0x005a000a,
+ 0x005a0832,
+ 0x005a381a,
+ 0x005a581a,
+ 0x005a6802,
+ 0x005aa822,
+ 0x005b1012,
+ 0x005c1002,
+ 0x005df002,
+ 0x005df80a,
+ 0x005e0002,
+ 0x005e081a,
+ 0x005e302a,
+ 0x005e502a,
+ 0x005e6802,
+ 0x005eb802,
+ 0x00600002,
+ 0x0060082a,
+ 0x00602002,
+ 0x0061e002,
+ 0x0061f022,
+ 0x0062083a,
+ 0x00623022,
+ 0x00625032,
+ 0x0062a812,
+ 0x00631012,
+ 0x00640802,
+ 0x0064101a,
+ 0x0065e002,
+ 0x0065f00a,
+ 0x0065f802,
+ 0x0066001a,
+ 0x00661002,
+ 0x0066181a,
+ 0x00663002,
+ 0x0066381a,
+ 0x0066501a,
+ 0x00666012,
+ 0x0066a812,
+ 0x00671012,
+ 0x0067980a,
+ 0x00680012,
+ 0x0068101a,
+ 0x0069d812,
+ 0x0069f002,
+ 0x0069f81a,
+ 0x006a0832,
+ 0x006a302a,
+ 0x006a502a,
+ 0x006a6802,
+ 0x006a7008,
+ 0x006ab802,
+ 0x006b1012,
+ 0x006c0802,
+ 0x006c101a,
+ 0x006e5002,
+ 0x006e7802,
+ 0x006e801a,
+ 0x006e9022,
+ 0x006eb002,
+ 0x006ec06a,
+ 0x006ef802,
+ 0x006f901a,
+ 0x00718802,
+ 0x0071980a,
+ 0x0071a062,
+ 0x00723872,
+ 0x00758802,
+ 0x0075980a,
+ 0x0075a082,
+ 0x00764062,
+ 0x0078c012,
+ 0x0079a802,
+ 0x0079b802,
+ 0x0079c802,
+ 0x0079f01a,
+ 0x007b88d2,
+ 0x007bf80a,
+ 0x007c0042,
+ 0x007c3012,
+ 0x007c68a2,
+ 0x007cca32,
+ 0x007e3002,
+ 0x00816832,
+ 0x0081880a,
+ 0x00819052,
+ 0x0081c812,
+ 0x0081d81a,
+ 0x0081e812,
+ 0x0082b01a,
+ 0x0082c012,
+ 0x0082f022,
+ 0x00838832,
+ 0x00841002,
+ 0x0084200a,
+ 0x00842812,
+ 0x00846802,
+ 0x0084e802,
+ 0x008805f4,
+ 0x008b047c,
+ 0x008d457b,
+ 0x009ae822,
+ 0x00b89022,
+ 0x00b8a80a,
+ 0x00b99012,
+ 0x00b9a00a,
+ 0x00ba9012,
+ 0x00bb9012,
+ 0x00bda012,
+ 0x00bdb00a,
+ 0x00bdb862,
+ 0x00bdf07a,
+ 0x00be3002,
+ 0x00be381a,
+ 0x00be48a2,
+ 0x00bee802,
+ 0x00c05822,
+ 0x00c07001,
+ 0x00c07802,
+ 0x00c42812,
+ 0x00c54802,
+ 0x00c90022,
+ 0x00c9183a,
+ 0x00c93812,
+ 0x00c9482a,
+ 0x00c9801a,
+ 0x00c99002,
+ 0x00c9985a,
+ 0x00c9c822,
+ 0x00d0b812,
+ 0x00d0c81a,
+ 0x00d0d802,
+ 0x00d2a80a,
+ 0x00d2b002,
+ 0x00d2b80a,
+ 0x00d2c062,
+ 0x00d30002,
+ 0x00d31002,
+ 0x00d32872,
+ 0x00d3685a,
+ 0x00d39892,
+ 0x00d3f802,
+ 0x00d581e2,
+ 0x00d80032,
+ 0x00d8200a,
+ 0x00d9a062,
+ 0x00d9d80a,
+ 0x00d9e002,
+ 0x00d9e84a,
+ 0x00da1002,
+ 0x00da181a,
+ 0x00db5882,
+ 0x00dc0012,
+ 0x00dc100a,
+ 0x00dd080a,
+ 0x00dd1032,
+ 0x00dd301a,
+ 0x00dd4012,
+ 0x00dd500a,
+ 0x00dd5822,
+ 0x00df3002,
+ 0x00df380a,
+ 0x00df4012,
+ 0x00df502a,
+ 0x00df6802,
+ 0x00df700a,
+ 0x00df7822,
+ 0x00df901a,
+ 0x00e1207a,
+ 0x00e16072,
+ 0x00e1a01a,
+ 0x00e1b012,
+ 0x00e68022,
+ 0x00e6a0c2,
+ 0x00e7080a,
+ 0x00e71062,
+ 0x00e76802,
+ 0x00e7a002,
+ 0x00e7b80a,
+ 0x00e7c012,
+ 0x00ee03f2,
+ 0x01005801,
+ 0x01006002,
+ 0x0100680d,
+ 0x01007011,
+ 0x01014061,
+ 0x0101e003,
+ 0x01024803,
+ 0x010300f1,
+ 0x01068202,
+ 0x01091003,
+ 0x0109c803,
+ 0x010ca053,
+ 0x010d4813,
+ 0x0118d013,
+ 0x01194003,
+ 0x011c4003,
+ 0x011e7803,
+ 0x011f48a3,
+ 0x011fc023,
+ 0x01261003,
+ 0x012d5013,
+ 0x012db003,
+ 0x012e0003,
+ 0x012fd833,
+ 0x01300053,
+ 0x013038b3,
+ 0x0130a713,
+ 0x01348753,
+ 0x013840a3,
+ 0x0138a003,
+ 0x0138b003,
+ 0x0138e803,
+ 0x01390803,
+ 0x01394003,
+ 0x01399813,
+ 0x013a2003,
+ 0x013a3803,
+ 0x013a6003,
+ 0x013a7003,
+ 0x013a9823,
+ 0x013ab803,
+ 0x013b1843,
+ 0x013ca823,
+ 0x013d0803,
+ 0x013d8003,
+ 0x013df803,
+ 0x0149a013,
+ 0x01582823,
+ 0x0158d813,
+ 0x015a8003,
+ 0x015aa803,
+ 0x01677822,
+ 0x016bf802,
+ 0x016f01f2,
+ 0x01815052,
+ 0x01818003,
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+ 0x069e89a7,
+ 0x069f6006,
+ 0x069f69a7,
+ 0x06a04006,
+ 0x06a049a7,
+ 0x06a12006,
+ 0x06a129a7,
+ 0x06a20006,
+ 0x06a209a7,
+ 0x06a2e006,
+ 0x06a2e9a7,
+ 0x06a3c006,
+ 0x06a3c9a7,
+ 0x06a4a006,
+ 0x06a4a9a7,
+ 0x06a58006,
+ 0x06a589a7,
+ 0x06a66006,
+ 0x06a669a7,
+ 0x06a74006,
+ 0x06a749a7,
+ 0x06a82006,
+ 0x06a829a7,
+ 0x06a90006,
+ 0x06a909a7,
+ 0x06a9e006,
+ 0x06a9e9a7,
+ 0x06aac006,
+ 0x06aac9a7,
+ 0x06aba006,
+ 0x06aba9a7,
+ 0x06ac8006,
+ 0x06ac89a7,
+ 0x06ad6006,
+ 0x06ad69a7,
+ 0x06ae4006,
+ 0x06ae49a7,
+ 0x06af2006,
+ 0x06af29a7,
+ 0x06b00006,
+ 0x06b009a7,
+ 0x06b0e006,
+ 0x06b0e9a7,
+ 0x06b1c006,
+ 0x06b1c9a7,
+ 0x06b2a006,
+ 0x06b2a9a7,
+ 0x06b38006,
+ 0x06b389a7,
+ 0x06b46006,
+ 0x06b469a7,
+ 0x06b54006,
+ 0x06b549a7,
+ 0x06b62006,
+ 0x06b629a7,
+ 0x06b70006,
+ 0x06b709a7,
+ 0x06b7e006,
+ 0x06b7e9a7,
+ 0x06b8c006,
+ 0x06b8c9a7,
+ 0x06b9a006,
+ 0x06b9a9a7,
+ 0x06ba8006,
+ 0x06ba89a7,
+ 0x06bb6006,
+ 0x06bb69a7,
+ 0x06bc4006,
+ 0x06bc49a7,
+ 0x06bd816c,
+ 0x06be5b0b,
+ 0x07d8f002,
+ 0x07f000f2,
+ 0x07f100f2,
+ 0x07f7f801,
+ 0x07fcf012,
+ 0x07ff80b1,
+ 0x080fe802,
+ 0x08170002,
+ 0x081bb042,
+ 0x08500822,
+ 0x08502812,
+ 0x08506032,
+ 0x0851c022,
+ 0x0851f802,
+ 0x08572812,
+ 0x08692032,
+ 0x08755812,
+ 0x0877e822,
+ 0x087a30a2,
+ 0x087c1032,
+ 0x0880000a,
+ 0x08800802,
+ 0x0880100a,
+ 0x0881c0e2,
+ 0x08838002,
+ 0x08839812,
+ 0x0883f822,
+ 0x0884100a,
+ 0x0885802a,
+ 0x08859832,
+ 0x0885b81a,
+ 0x0885c812,
+ 0x0885e808,
+ 0x08861002,
+ 0x08866808,
+ 0x08880022,
+ 0x08893842,
+ 0x0889600a,
+ 0x08896872,
+ 0x088a281a,
+ 0x088b9802,
+ 0x088c0012,
+ 0x088c100a,
+ 0x088d982a,
+ 0x088db082,
+ 0x088df81a,
+ 0x088e1018,
+ 0x088e4832,
+ 0x088e700a,
+ 0x088e7802,
+ 0x0891602a,
+ 0x08917822,
+ 0x0891901a,
+ 0x0891a002,
+ 0x0891a80a,
+ 0x0891b012,
+ 0x0891f002,
+ 0x08920802,
+ 0x0896f802,
+ 0x0897002a,
+ 0x08971872,
+ 0x08980012,
+ 0x0898101a,
+ 0x0899d812,
+ 0x0899f002,
+ 0x0899f80a,
+ 0x089a0002,
+ 0x089a083a,
+ 0x089a381a,
+ 0x089a582a,
+ 0x089ab802,
+ 0x089b101a,
+ 0x089b3062,
+ 0x089b8042,
+ 0x08a1a82a,
+ 0x08a1c072,
+ 0x08a2001a,
+ 0x08a21022,
+ 0x08a2280a,
+ 0x08a23002,
+ 0x08a2f002,
+ 0x08a58002,
+ 0x08a5881a,
+ 0x08a59852,
+ 0x08a5c80a,
+ 0x08a5d002,
+ 0x08a5d81a,
+ 0x08a5e802,
+ 0x08a5f00a,
+ 0x08a5f812,
+ 0x08a6080a,
+ 0x08a61012,
+ 0x08ad7802,
+ 0x08ad801a,
+ 0x08ad9032,
+ 0x08adc03a,
+ 0x08ade012,
+ 0x08adf00a,
+ 0x08adf812,
+ 0x08aee012,
+ 0x08b1802a,
+ 0x08b19872,
+ 0x08b1d81a,
+ 0x08b1e802,
+ 0x08b1f00a,
+ 0x08b1f812,
+ 0x08b55802,
+ 0x08b5600a,
+ 0x08b56802,
+ 0x08b5701a,
+ 0x08b58052,
+ 0x08b5b00a,
+ 0x08b5b802,
+ 0x08b8e822,
+ 0x08b91032,
+ 0x08b9300a,
+ 0x08b93842,
+ 0x08c1602a,
+ 0x08c17882,
+ 0x08c1c00a,
+ 0x08c1c812,
+ 0x08c98002,
+ 0x08c9884a,
+ 0x08c9b81a,
+ 0x08c9d812,
+ 0x08c9e80a,
+ 0x08c9f002,
+ 0x08c9f808,
+ 0x08ca000a,
+ 0x08ca0808,
+ 0x08ca100a,
+ 0x08ca1802,
+ 0x08ce882a,
+ 0x08cea032,
+ 0x08ced012,
+ 0x08cee03a,
+ 0x08cf0002,
+ 0x08cf200a,
+ 0x08d00892,
+ 0x08d19852,
+ 0x08d1c80a,
+ 0x08d1d008,
+ 0x08d1d832,
+ 0x08d23802,
+ 0x08d28852,
+ 0x08d2b81a,
+ 0x08d2c822,
+ 0x08d42058,
+ 0x08d450c2,
+ 0x08d4b80a,
+ 0x08d4c012,
+ 0x08e1780a,
+ 0x08e18062,
+ 0x08e1c052,
+ 0x08e1f00a,
+ 0x08e1f802,
+ 0x08e49152,
+ 0x08e5480a,
+ 0x08e55062,
+ 0x08e5880a,
+ 0x08e59012,
+ 0x08e5a00a,
+ 0x08e5a812,
+ 0x08e98852,
+ 0x08e9d002,
+ 0x08e9e012,
+ 0x08e9f862,
+ 0x08ea3008,
+ 0x08ea3802,
+ 0x08ec504a,
+ 0x08ec8012,
+ 0x08ec981a,
+ 0x08eca802,
+ 0x08ecb00a,
+ 0x08ecb802,
+ 0x08f79812,
+ 0x08f7a81a,
+ 0x08f80012,
+ 0x08f81008,
+ 0x08f8180a,
+ 0x08f9a01a,
+ 0x08f9b042,
+ 0x08f9f01a,
+ 0x08fa0002,
+ 0x08fa080a,
+ 0x08fa1002,
+ 0x09a180f1,
+ 0x09a20002,
+ 0x09a238e2,
+ 0x0b578042,
+ 0x0b598062,
+ 0x0b7a7802,
+ 0x0b7a8b6a,
+ 0x0b7c7832,
+ 0x0b7f2002,
+ 0x0b7f801a,
+ 0x0de4e812,
+ 0x0de50031,
+ 0x0e7802d2,
+ 0x0e798162,
+ 0x0e8b2802,
+ 0x0e8b300a,
+ 0x0e8b3822,
+ 0x0e8b680a,
+ 0x0e8b7042,
+ 0x0e8b9871,
+ 0x0e8bd872,
+ 0x0e8c2862,
+ 0x0e8d5032,
+ 0x0e921022,
+ 0x0ed00362,
+ 0x0ed1db12,
+ 0x0ed3a802,
+ 0x0ed42002,
+ 0x0ed4d842,
+ 0x0ed508e2,
+ 0x0f000062,
+ 0x0f004102,
+ 0x0f00d862,
+ 0x0f011812,
+ 0x0f013042,
+ 0x0f047802,
+ 0x0f098062,
+ 0x0f157002,
+ 0x0f176032,
+ 0x0f276032,
+ 0x0f468062,
+ 0x0f4a2062,
+ 0x0f8007f3,
+ 0x0f8407f3,
+ 0x0f886823,
+ 0x0f897803,
+ 0x0f8b6053,
+ 0x0f8bf013,
+ 0x0f8c7003,
+ 0x0f8c8893,
+ 0x0f8d6b83,
+ 0x0f8f3199,
+ 0x0f9008e3,
+ 0x0f90d003,
+ 0x0f917803,
+ 0x0f919083,
+ 0x0f91e033,
+ 0x0f924ff3,
+ 0x0f964ff3,
+ 0x0f9a4ff3,
+ 0x0f9e4b13,
+ 0x0f9fd842,
+ 0x0fa007f3,
+ 0x0fa407f3,
+ 0x0fa803d3,
+ 0x0faa37f3,
+ 0x0fae37f3,
+ 0x0fb23093,
+ 0x0fb407f3,
+ 0x0fbba0b3,
+ 0x0fbeaaa3,
+ 0x0fc06033,
+ 0x0fc24073,
+ 0x0fc2d053,
+ 0x0fc44073,
+ 0x0fc57513,
+ 0x0fc862e3,
+ 0x0fc9e093,
+ 0x0fca3ff3,
+ 0x0fce3ff3,
+ 0x0fd23ff3,
+ 0x0fd63b83,
+ 0x0fe007f3,
+ 0x0fe407f3,
+ 0x0fe807f3,
+ 0x0fec07f3,
+ 0x0ff007f3,
+ 0x0ff407f3,
+ 0x0ff807f3,
+ 0x0ffc07d3,
+ 0x700001f1,
+ 0x700105f2,
+ 0x700407f1,
+ 0x700807f2,
+ 0x700c06f2,
+ 0x700f87f1,
+ 0x701387f1,
+ 0x701787f1,
+ 0x701b87f1,
+ 0x701f87f1,
+ 0x702387f1,
+ 0x702787f1,
+ 0x702b87f1,
+ 0x702f87f1,
+ 0x703387f1,
+ 0x703787f1,
+ 0x703b87f1,
+ 0x703f87f1,
+ 0x704387f1,
+ 0x704787f1,
+ 0x704b87f1,
+ 0x704f87f1,
+ 0x705387f1,
+ 0x705787f1,
+ 0x705b87f1,
+ 0x705f87f1,
+ 0x706387f1,
+ 0x706787f1,
+ 0x706b87f1,
+ 0x706f87f1,
+ 0x707387f1,
+ 0x707787f1,
+ 0x707b87f1,
+ 0x707f80f1};
+// clang-format on
+
+/// Returns the extended grapheme cluster bondary property of a code point.
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __property __get_property(const char32_t __code_point) noexcept {
+ // The algorithm searches for the upper bound of the range and, when found,
+ // steps back one entry. This algorithm is used since the code point can be
+ // anywhere in the range. After a lower bound is found the next step is to
+ // compare whether the code unit is indeed in the range.
+ //
+ // Since the entry contains a code unit, size, and property the code point
+ // being sought needs to be adjusted. Just shifting the code point to the
+ // proper position doesn't work; suppose an entry has property 0, size 1,
+ // and lower bound 3. This results in the entry 0x1810.
+ // When searching for code point 3 it will search for 0x1800, find 0x1810
+ // and moves to the previous entry. Thus the lower bound value will never
+ // be found.
+ // The simple solution is to set the bits belonging to the property and
+ // size. Then the upper bound for code point 3 will return the entry after
+ // 0x1810. After moving to the previous entry the algorithm arrives at the
+ // correct entry.
+ ptrdiff_t __i = std::ranges::upper_bound(__entries, (__code_point << 11) | 0x7ffu) - __entries;
+ if (__i == 0)
+ return __property::__none;
+
+ --__i;
+ uint32_t __upper_bound = (__entries[__i] >> 11) + ((__entries[__i] >> 4) & 0x7f);
+ if (__code_point <= __upper_bound)
+ return static_cast<__property>(__entries[__i] & 0xf);
+
+ return __property::__none;
+}
+
+} // namespace __extended_grapheme_custer_property_boundary
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_EXTENDED_GRAPHEME_CLUSTER_TABLE_H
diff --git a/libcxx/include/__cxx03/__format/format_arg.h b/libcxx/include/__cxx03/__format/format_arg.h
new file mode 100644
index 00000000000000..aa02f81dc40e2d
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_arg.h
@@ -0,0 +1,401 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_ARG_H
+#define _LIBCPP___FORMAT_FORMAT_ARG_H
+
+#include <__assert>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_parse_context.h>
+#include <__functional/invoke.h>
+#include <__fwd/format.h>
+#include <__memory/addressof.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/remove_const.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/unreachable.h>
+#include <__variant/monostate.h>
+#include <cstdint>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __format {
+/// The type stored in @ref basic_format_arg.
+///
+/// @note The 128-bit types are unconditionally in the list to avoid the values
+/// of the enums to depend on the availability of 128-bit integers.
+///
+/// @note The value is stored as a 5-bit value in the __packed_arg_t_bits. This
+/// limits the maximum number of elements to 32.
+/// When modifying update the test
+/// test/libcxx/utilities/format/format.arguments/format.arg/arg_t.compile.pass.cpp
+/// It could be packed in 4-bits but that means a new type directly becomes an
+/// ABI break. The packed type is 64-bit so this reduces the maximum number of
+/// packed elements from 16 to 12.
+///
+/// @note Some members of this enum are an extension. These extensions need
+/// special behaviour in visit_format_arg. There they need to be wrapped in a
+/// handle to satisfy the user observable behaviour. The internal function
+/// __visit_format_arg doesn't do this wrapping. So in the format functions
+/// this function is used to avoid unneeded overhead.
+enum class __arg_t : uint8_t {
+ __none,
+ __boolean,
+ __char_type,
+ __int,
+ __long_long,
+ __i128, // extension
+ __unsigned,
+ __unsigned_long_long,
+ __u128, // extension
+ __float,
+ __double,
+ __long_double,
+ __const_char_type_ptr,
+ __string_view,
+ __ptr,
+ __handle
+};
+
+inline constexpr unsigned __packed_arg_t_bits = 5;
+inline constexpr uint8_t __packed_arg_t_mask = 0x1f;
+
+inline constexpr unsigned __packed_types_storage_bits = 64;
+inline constexpr unsigned __packed_types_max = __packed_types_storage_bits / __packed_arg_t_bits;
+
+_LIBCPP_HIDE_FROM_ABI constexpr bool __use_packed_format_arg_store(size_t __size) {
+ return __size <= __packed_types_max;
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr __arg_t __get_packed_type(uint64_t __types, size_t __id) {
+ _LIBCPP_ASSERT_INTERNAL(__id <= __packed_types_max, "");
+
+ if (__id > 0)
+ __types >>= __id * __packed_arg_t_bits;
+
+ return static_cast<__format::__arg_t>(__types & __packed_arg_t_mask);
+}
+
+} // namespace __format
+
+// This function is not user observable, so it can directly use the non-standard
+// types of the "variant". See __arg_t for more details.
+template <class _Visitor, class _Context>
+_LIBCPP_HIDE_FROM_ABI decltype(auto) __visit_format_arg(_Visitor&& __vis, basic_format_arg<_Context> __arg) {
+ switch (__arg.__type_) {
+ case __format::__arg_t::__none:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__monostate_);
+ case __format::__arg_t::__boolean:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__boolean_);
+ case __format::__arg_t::__char_type:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__char_type_);
+ case __format::__arg_t::__int:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__int_);
+ case __format::__arg_t::__long_long:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__long_long_);
+ case __format::__arg_t::__i128:
+# ifndef _LIBCPP_HAS_NO_INT128
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__i128_);
+# else
+ __libcpp_unreachable();
+# endif
+ case __format::__arg_t::__unsigned:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__unsigned_);
+ case __format::__arg_t::__unsigned_long_long:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__unsigned_long_long_);
+ case __format::__arg_t::__u128:
+# ifndef _LIBCPP_HAS_NO_INT128
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__u128_);
+# else
+ __libcpp_unreachable();
+# endif
+ case __format::__arg_t::__float:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__float_);
+ case __format::__arg_t::__double:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__double_);
+ case __format::__arg_t::__long_double:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__long_double_);
+ case __format::__arg_t::__const_char_type_ptr:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__const_char_type_ptr_);
+ case __format::__arg_t::__string_view:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__string_view_);
+ case __format::__arg_t::__ptr:
+ return std::invoke(std::forward<_Visitor>(__vis), __arg.__value_.__ptr_);
+ case __format::__arg_t::__handle:
+ return std::invoke(
+ std::forward<_Visitor>(__vis), typename basic_format_arg<_Context>::handle{__arg.__value_.__handle_});
+ }
+
+ __libcpp_unreachable();
+}
+
+# if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+
+template <class _Rp, class _Visitor, class _Context>
+_LIBCPP_HIDE_FROM_ABI _Rp __visit_format_arg(_Visitor&& __vis, basic_format_arg<_Context> __arg) {
+ switch (__arg.__type_) {
+ case __format::__arg_t::__none:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__monostate_);
+ case __format::__arg_t::__boolean:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__boolean_);
+ case __format::__arg_t::__char_type:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__char_type_);
+ case __format::__arg_t::__int:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__int_);
+ case __format::__arg_t::__long_long:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__long_long_);
+ case __format::__arg_t::__i128:
+# ifndef _LIBCPP_HAS_NO_INT128
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__i128_);
+# else
+ __libcpp_unreachable();
+# endif
+ case __format::__arg_t::__unsigned:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__unsigned_);
+ case __format::__arg_t::__unsigned_long_long:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__unsigned_long_long_);
+ case __format::__arg_t::__u128:
+# ifndef _LIBCPP_HAS_NO_INT128
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__u128_);
+# else
+ __libcpp_unreachable();
+# endif
+ case __format::__arg_t::__float:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__float_);
+ case __format::__arg_t::__double:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__double_);
+ case __format::__arg_t::__long_double:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__long_double_);
+ case __format::__arg_t::__const_char_type_ptr:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__const_char_type_ptr_);
+ case __format::__arg_t::__string_view:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__string_view_);
+ case __format::__arg_t::__ptr:
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), __arg.__value_.__ptr_);
+ case __format::__arg_t::__handle:
+ return std::invoke_r<_Rp>(
+ std::forward<_Visitor>(__vis), typename basic_format_arg<_Context>::handle{__arg.__value_.__handle_});
+ }
+
+ __libcpp_unreachable();
+}
+
+# endif // _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+
+/// Contains the values used in basic_format_arg.
+///
+/// This is a separate type so it's possible to store the values and types in
+/// separate arrays.
+template <class _Context>
+class __basic_format_arg_value {
+ using _CharT = typename _Context::char_type;
+
+public:
+ /// Contains the implementation for basic_format_arg::handle.
+ struct __handle {
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI explicit __handle(_Tp& __v) noexcept
+ : __ptr_(std::addressof(__v)),
+ __format_([](basic_format_parse_context<_CharT>& __parse_ctx, _Context& __ctx, const void* __ptr) {
+ using _Dp = remove_const_t<_Tp>;
+ using _Qp = conditional_t<__formattable_with<const _Dp, _Context>, const _Dp, _Dp>;
+ static_assert(__formattable_with<_Qp, _Context>, "Mandated by [format.arg]/10");
+
+ typename _Context::template formatter_type<_Dp> __f;
+ __parse_ctx.advance_to(__f.parse(__parse_ctx));
+ __ctx.advance_to(__f.format(*const_cast<_Qp*>(static_cast<const _Dp*>(__ptr)), __ctx));
+ }) {}
+
+ const void* __ptr_;
+ void (*__format_)(basic_format_parse_context<_CharT>&, _Context&, const void*);
+ };
+
+ union {
+ monostate __monostate_;
+ bool __boolean_;
+ _CharT __char_type_;
+ int __int_;
+ unsigned __unsigned_;
+ long long __long_long_;
+ unsigned long long __unsigned_long_long_;
+# ifndef _LIBCPP_HAS_NO_INT128
+ __int128_t __i128_;
+ __uint128_t __u128_;
+# endif
+ float __float_;
+ double __double_;
+ long double __long_double_;
+ const _CharT* __const_char_type_ptr_;
+ basic_string_view<_CharT> __string_view_;
+ const void* __ptr_;
+ __handle __handle_;
+ };
+
+ // These constructors contain the exact storage type used. If adjustments are
+ // required, these will be done in __create_format_arg.
+
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value() noexcept : __monostate_() {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(bool __value) noexcept : __boolean_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(_CharT __value) noexcept : __char_type_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(int __value) noexcept : __int_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(unsigned __value) noexcept : __unsigned_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(long long __value) noexcept : __long_long_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(unsigned long long __value) noexcept
+ : __unsigned_long_long_(__value) {}
+# ifndef _LIBCPP_HAS_NO_INT128
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(__int128_t __value) noexcept : __i128_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(__uint128_t __value) noexcept : __u128_(__value) {}
+# endif
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(float __value) noexcept : __float_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(double __value) noexcept : __double_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(long double __value) noexcept : __long_double_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(const _CharT* __value) noexcept : __const_char_type_ptr_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(basic_string_view<_CharT> __value) noexcept
+ : __string_view_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(const void* __value) noexcept : __ptr_(__value) {}
+ _LIBCPP_HIDE_FROM_ABI __basic_format_arg_value(__handle&& __value) noexcept : __handle_(std::move(__value)) {}
+};
+
+template <class _Context>
+class _LIBCPP_TEMPLATE_VIS basic_format_arg {
+public:
+ class _LIBCPP_TEMPLATE_VIS handle;
+
+ _LIBCPP_HIDE_FROM_ABI basic_format_arg() noexcept : __type_{__format::__arg_t::__none} {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const noexcept { return __type_ != __format::__arg_t::__none; }
+
+# if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+
+ // This function is user facing, so it must wrap the non-standard types of
+ // the "variant" in a handle to stay conforming. See __arg_t for more details.
+ template <class _Visitor>
+ _LIBCPP_HIDE_FROM_ABI decltype(auto) visit(this basic_format_arg __arg, _Visitor&& __vis) {
+ switch (__arg.__type_) {
+# ifndef _LIBCPP_HAS_NO_INT128
+ case __format::__arg_t::__i128: {
+ typename __basic_format_arg_value<_Context>::__handle __h{__arg.__value_.__i128_};
+ return std::invoke(std::forward<_Visitor>(__vis), typename basic_format_arg<_Context>::handle{__h});
+ }
+
+ case __format::__arg_t::__u128: {
+ typename __basic_format_arg_value<_Context>::__handle __h{__arg.__value_.__u128_};
+ return std::invoke(std::forward<_Visitor>(__vis), typename basic_format_arg<_Context>::handle{__h});
+ }
+# endif
+ default:
+ return std::__visit_format_arg(std::forward<_Visitor>(__vis), __arg);
+ }
+ }
+
+ // This function is user facing, so it must wrap the non-standard types of
+ // the "variant" in a handle to stay conforming. See __arg_t for more details.
+ template <class _Rp, class _Visitor>
+ _LIBCPP_HIDE_FROM_ABI _Rp visit(this basic_format_arg __arg, _Visitor&& __vis) {
+ switch (__arg.__type_) {
+# ifndef _LIBCPP_HAS_NO_INT128
+ case __format::__arg_t::__i128: {
+ typename __basic_format_arg_value<_Context>::__handle __h{__arg.__value_.__i128_};
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), typename basic_format_arg<_Context>::handle{__h});
+ }
+
+ case __format::__arg_t::__u128: {
+ typename __basic_format_arg_value<_Context>::__handle __h{__arg.__value_.__u128_};
+ return std::invoke_r<_Rp>(std::forward<_Visitor>(__vis), typename basic_format_arg<_Context>::handle{__h});
+ }
+# endif
+ default:
+ return std::__visit_format_arg<_Rp>(std::forward<_Visitor>(__vis), __arg);
+ }
+ }
+
+# endif // _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+
+private:
+ using char_type = typename _Context::char_type;
+
+ // TODO FMT Implement constrain [format.arg]/4
+ // Constraints: The template specialization
+ // typename Context::template formatter_type<T>
+ // meets the Formatter requirements ([formatter.requirements]). The extent
+ // to which an implementation determines that the specialization meets the
+ // Formatter requirements is unspecified, except that as a minimum the
+ // expression
+ // typename Context::template formatter_type<T>()
+ // .format(declval<const T&>(), declval<Context&>())
+ // shall be well-formed when treated as an unevaluated operand.
+
+public:
+ __basic_format_arg_value<_Context> __value_;
+ __format::__arg_t __type_;
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_format_arg(__format::__arg_t __type,
+ __basic_format_arg_value<_Context> __value) noexcept
+ : __value_(__value), __type_(__type) {}
+};
+
+template <class _Context>
+class _LIBCPP_TEMPLATE_VIS basic_format_arg<_Context>::handle {
+public:
+ _LIBCPP_HIDE_FROM_ABI void format(basic_format_parse_context<char_type>& __parse_ctx, _Context& __ctx) const {
+ __handle_.__format_(__parse_ctx, __ctx, __handle_.__ptr_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit handle(typename __basic_format_arg_value<_Context>::__handle& __handle) noexcept
+ : __handle_(__handle) {}
+
+private:
+ typename __basic_format_arg_value<_Context>::__handle& __handle_;
+};
+
+// This function is user facing, so it must wrap the non-standard types of
+// the "variant" in a handle to stay conforming. See __arg_t for more details.
+template <class _Visitor, class _Context>
+# if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+_LIBCPP_DEPRECATED_IN_CXX26
+# endif
+ _LIBCPP_HIDE_FROM_ABI decltype(auto)
+ visit_format_arg(_Visitor&& __vis, basic_format_arg<_Context> __arg) {
+ switch (__arg.__type_) {
+# ifndef _LIBCPP_HAS_NO_INT128
+ case __format::__arg_t::__i128: {
+ typename __basic_format_arg_value<_Context>::__handle __h{__arg.__value_.__i128_};
+ return std::invoke(std::forward<_Visitor>(__vis), typename basic_format_arg<_Context>::handle{__h});
+ }
+
+ case __format::__arg_t::__u128: {
+ typename __basic_format_arg_value<_Context>::__handle __h{__arg.__value_.__u128_};
+ return std::invoke(std::forward<_Visitor>(__vis), typename basic_format_arg<_Context>::handle{__h});
+ }
+# endif // _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+ default:
+ return std::__visit_format_arg(std::forward<_Visitor>(__vis), __arg);
+ }
+}
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_FORMAT_ARG_H
diff --git a/libcxx/include/__cxx03/__format/format_arg_store.h b/libcxx/include/__cxx03/__format/format_arg_store.h
new file mode 100644
index 00000000000000..23a599e9957599
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_arg_store.h
@@ -0,0 +1,266 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_ARG_STORE_H
+#define _LIBCPP___FORMAT_FORMAT_ARG_STORE_H
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#include <__concepts/arithmetic.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_arg.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/extent.h>
+#include <__type_traits/remove_const.h>
+#include <string>
+#include <string_view>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __format {
+
+/// \returns The @c __arg_t based on the type of the formatting argument.
+///
+/// \pre \c __formattable<_Tp, typename _Context::char_type>
+template <class _Context, class _Tp>
+consteval __arg_t __determine_arg_t();
+
+// Boolean
+template <class, same_as<bool> _Tp>
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__boolean;
+}
+
+// Char
+template <class _Context, same_as<typename _Context::char_type> _Tp>
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__char_type;
+}
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _Context, class _CharT>
+ requires(same_as<typename _Context::char_type, wchar_t> && same_as<_CharT, char>)
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__char_type;
+}
+# endif
+
+// Signed integers
+template <class, __libcpp_signed_integer _Tp>
+consteval __arg_t __determine_arg_t() {
+ if constexpr (sizeof(_Tp) <= sizeof(int))
+ return __arg_t::__int;
+ else if constexpr (sizeof(_Tp) <= sizeof(long long))
+ return __arg_t::__long_long;
+# ifndef _LIBCPP_HAS_NO_INT128
+ else if constexpr (sizeof(_Tp) == sizeof(__int128_t))
+ return __arg_t::__i128;
+# endif
+ else
+ static_assert(sizeof(_Tp) == 0, "an unsupported signed integer was used");
+}
+
+// Unsigned integers
+template <class, __libcpp_unsigned_integer _Tp>
+consteval __arg_t __determine_arg_t() {
+ if constexpr (sizeof(_Tp) <= sizeof(unsigned))
+ return __arg_t::__unsigned;
+ else if constexpr (sizeof(_Tp) <= sizeof(unsigned long long))
+ return __arg_t::__unsigned_long_long;
+# ifndef _LIBCPP_HAS_NO_INT128
+ else if constexpr (sizeof(_Tp) == sizeof(__uint128_t))
+ return __arg_t::__u128;
+# endif
+ else
+ static_assert(sizeof(_Tp) == 0, "an unsupported unsigned integer was used");
+}
+
+// Floating-point
+template <class, same_as<float> _Tp>
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__float;
+}
+template <class, same_as<double> _Tp>
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__double;
+}
+template <class, same_as<long double> _Tp>
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__long_double;
+}
+
+// Char pointer
+template <class _Context, class _Tp>
+ requires(same_as<typename _Context::char_type*, _Tp> || same_as<const typename _Context::char_type*, _Tp>)
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__const_char_type_ptr;
+}
+
+// Char array
+template <class _Context, class _Tp>
+ requires(is_array_v<_Tp> && same_as<_Tp, typename _Context::char_type[extent_v<_Tp>]>)
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__string_view;
+}
+
+// String view
+template <class _Context, class _Tp>
+ requires(same_as<typename _Context::char_type, typename _Tp::value_type> &&
+ same_as<_Tp, basic_string_view<typename _Tp::value_type, typename _Tp::traits_type>>)
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__string_view;
+}
+
+// String
+template <class _Context, class _Tp>
+ requires(
+ same_as<typename _Context::char_type, typename _Tp::value_type> &&
+ same_as<_Tp, basic_string<typename _Tp::value_type, typename _Tp::traits_type, typename _Tp::allocator_type>>)
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__string_view;
+}
+
+// Pointers
+template <class, class _Ptr>
+ requires(same_as<_Ptr, void*> || same_as<_Ptr, const void*> || same_as<_Ptr, nullptr_t>)
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__ptr;
+}
+
+// Handle
+//
+// Note this version can't be constrained avoiding ambiguous overloads.
+// That means it can be instantiated by disabled formatters. To solve this, a
+// constrained version for not formattable formatters is added.
+template <class _Context, class _Tp>
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__handle;
+}
+
+// The overload for not formattable types allows triggering the static
+// assertion below.
+template <class _Context, class _Tp>
+ requires(!__formattable_with<_Tp, _Context>)
+consteval __arg_t __determine_arg_t() {
+ return __arg_t::__none;
+}
+
+// Pseudo constuctor for basic_format_arg
+//
+// Modeled after template<class T> explicit basic_format_arg(T& v) noexcept;
+// [format.arg]/4-6
+template <class _Context, class _Tp>
+_LIBCPP_HIDE_FROM_ABI basic_format_arg<_Context> __create_format_arg(_Tp& __value) noexcept {
+ using _Dp = remove_const_t<_Tp>;
+ constexpr __arg_t __arg = __determine_arg_t<_Context, _Dp>();
+ static_assert(__arg != __arg_t::__none, "the supplied type is not formattable");
+ static_assert(__formattable_with<_Tp, _Context>);
+
+ // Not all types can be used to directly initialize the
+ // __basic_format_arg_value. First handle all types needing adjustment, the
+ // final else requires no adjustment.
+ if constexpr (__arg == __arg_t::__char_type)
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ if constexpr (same_as<typename _Context::char_type, wchar_t> && same_as<_Dp, char>)
+ return basic_format_arg<_Context>{__arg, static_cast<wchar_t>(static_cast<unsigned char>(__value))};
+ else
+# endif
+ return basic_format_arg<_Context>{__arg, __value};
+ else if constexpr (__arg == __arg_t::__int)
+ return basic_format_arg<_Context>{__arg, static_cast<int>(__value)};
+ else if constexpr (__arg == __arg_t::__long_long)
+ return basic_format_arg<_Context>{__arg, static_cast<long long>(__value)};
+ else if constexpr (__arg == __arg_t::__unsigned)
+ return basic_format_arg<_Context>{__arg, static_cast<unsigned>(__value)};
+ else if constexpr (__arg == __arg_t::__unsigned_long_long)
+ return basic_format_arg<_Context>{__arg, static_cast<unsigned long long>(__value)};
+ else if constexpr (__arg == __arg_t::__string_view)
+ // Using std::size on a character array will add the NUL-terminator to the size.
+ if constexpr (is_array_v<_Dp>)
+ return basic_format_arg<_Context>{
+ __arg, basic_string_view<typename _Context::char_type>{__value, extent_v<_Dp> - 1}};
+ else
+ // When the _Traits or _Allocator are different an implicit conversion will
+ // fail.
+ return basic_format_arg<_Context>{
+ __arg, basic_string_view<typename _Context::char_type>{__value.data(), __value.size()}};
+ else if constexpr (__arg == __arg_t::__ptr)
+ return basic_format_arg<_Context>{__arg, static_cast<const void*>(__value)};
+ else if constexpr (__arg == __arg_t::__handle)
+ return basic_format_arg<_Context>{__arg, typename __basic_format_arg_value<_Context>::__handle{__value}};
+ else
+ return basic_format_arg<_Context>{__arg, __value};
+}
+
+template <class _Context, class... _Args>
+_LIBCPP_HIDE_FROM_ABI void
+__create_packed_storage(uint64_t& __types, __basic_format_arg_value<_Context>* __values, _Args&... __args) noexcept {
+ int __shift = 0;
+ (
+ [&] {
+ basic_format_arg<_Context> __arg = __format::__create_format_arg<_Context>(__args);
+ if (__shift != 0)
+ __types |= static_cast<uint64_t>(__arg.__type_) << __shift;
+ else
+ // Assigns the initial value.
+ __types = static_cast<uint64_t>(__arg.__type_);
+ __shift += __packed_arg_t_bits;
+ *__values++ = __arg.__value_;
+ }(),
+ ...);
+}
+
+template <class _Context, class... _Args>
+_LIBCPP_HIDE_FROM_ABI void __store_basic_format_arg(basic_format_arg<_Context>* __data, _Args&... __args) noexcept {
+ ([&] { *__data++ = __format::__create_format_arg<_Context>(__args); }(), ...);
+}
+
+template <class _Context, size_t _Np>
+struct __packed_format_arg_store {
+ __basic_format_arg_value<_Context> __values_[_Np];
+ uint64_t __types_ = 0;
+};
+
+template <class _Context, size_t _Np>
+struct __unpacked_format_arg_store {
+ basic_format_arg<_Context> __args_[_Np];
+};
+
+} // namespace __format
+
+template <class _Context, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS __format_arg_store {
+ _LIBCPP_HIDE_FROM_ABI __format_arg_store(_Args&... __args) noexcept {
+ if constexpr (sizeof...(_Args) != 0) {
+ if constexpr (__format::__use_packed_format_arg_store(sizeof...(_Args)))
+ __format::__create_packed_storage(__storage.__types_, __storage.__values_, __args...);
+ else
+ __format::__store_basic_format_arg<_Context>(__storage.__args_, __args...);
+ }
+ }
+
+ using _Storage =
+ conditional_t<__format::__use_packed_format_arg_store(sizeof...(_Args)),
+ __format::__packed_format_arg_store<_Context, sizeof...(_Args)>,
+ __format::__unpacked_format_arg_store<_Context, sizeof...(_Args)>>;
+
+ _Storage __storage;
+};
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMAT_ARG_STORE_H
diff --git a/libcxx/include/__cxx03/__format/format_args.h b/libcxx/include/__cxx03/__format/format_args.h
new file mode 100644
index 00000000000000..07923570f38930
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_args.h
@@ -0,0 +1,78 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_ARGS_H
+#define _LIBCPP___FORMAT_FORMAT_ARGS_H
+
+#include <__config>
+#include <__format/format_arg.h>
+#include <__format/format_arg_store.h>
+#include <__fwd/format.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Context>
+class _LIBCPP_TEMPLATE_VIS basic_format_args {
+public:
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI basic_format_args(const __format_arg_store<_Context, _Args...>& __store) noexcept
+ : __size_(sizeof...(_Args)) {
+ if constexpr (sizeof...(_Args) != 0) {
+ if constexpr (__format::__use_packed_format_arg_store(sizeof...(_Args))) {
+ __values_ = __store.__storage.__values_;
+ __types_ = __store.__storage.__types_;
+ } else
+ __args_ = __store.__storage.__args_;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_format_arg<_Context> get(size_t __id) const noexcept {
+ if (__id >= __size_)
+ return basic_format_arg<_Context>{};
+
+ if (__format::__use_packed_format_arg_store(__size_))
+ return basic_format_arg<_Context>{__format::__get_packed_type(__types_, __id), __values_[__id]};
+
+ return __args_[__id];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_t __size() const noexcept { return __size_; }
+
+private:
+ size_t __size_{0};
+ // [format.args]/5
+ // [Note 1: Implementations are encouraged to optimize the representation of
+ // basic_format_args for small number of formatting arguments by storing
+ // indices of type alternatives separately from values and packing the
+ // former. - end note]
+ union {
+ struct {
+ const __basic_format_arg_value<_Context>* __values_;
+ uint64_t __types_;
+ };
+ const basic_format_arg<_Context>* __args_;
+ };
+};
+
+template <class _Context, class... _Args>
+basic_format_args(__format_arg_store<_Context, _Args...>) -> basic_format_args<_Context>;
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMAT_ARGS_H
diff --git a/libcxx/include/__cxx03/__format/format_context.h b/libcxx/include/__cxx03/__format/format_context.h
new file mode 100644
index 00000000000000..20c07559eae448
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_context.h
@@ -0,0 +1,220 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_CONTEXT_H
+#define _LIBCPP___FORMAT_FORMAT_CONTEXT_H
+
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/buffer.h>
+#include <__format/format_arg.h>
+#include <__format/format_arg_store.h>
+#include <__format/format_args.h>
+#include <__format/format_error.h>
+#include <__fwd/format.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/concepts.h>
+#include <__memory/addressof.h>
+#include <__utility/move.h>
+#include <__variant/monostate.h>
+#include <cstddef>
+
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+# include <__locale>
+# include <optional>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _OutIt, class _CharT>
+ requires output_iterator<_OutIt, const _CharT&>
+class _LIBCPP_TEMPLATE_VIS basic_format_context;
+
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+/**
+ * Helper to create a basic_format_context.
+ *
+ * This is needed since the constructor is private.
+ */
+template <class _OutIt, class _CharT>
+_LIBCPP_HIDE_FROM_ABI basic_format_context<_OutIt, _CharT>
+__format_context_create(_OutIt __out_it,
+ basic_format_args<basic_format_context<_OutIt, _CharT>> __args,
+ optional<std::locale>&& __loc = nullopt) {
+ return std::basic_format_context(std::move(__out_it), __args, std::move(__loc));
+}
+# else
+template <class _OutIt, class _CharT>
+_LIBCPP_HIDE_FROM_ABI basic_format_context<_OutIt, _CharT>
+__format_context_create(_OutIt __out_it, basic_format_args<basic_format_context<_OutIt, _CharT>> __args) {
+ return std::basic_format_context(std::move(__out_it), __args);
+}
+# endif
+
+using format_context = basic_format_context<back_insert_iterator<__format::__output_buffer<char>>, char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wformat_context = basic_format_context< back_insert_iterator<__format::__output_buffer<wchar_t>>, wchar_t>;
+# endif
+
+template <class _OutIt, class _CharT>
+ requires output_iterator<_OutIt, const _CharT&>
+class
+ // clang-format off
+ _LIBCPP_TEMPLATE_VIS
+ _LIBCPP_PREFERRED_NAME(format_context)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wformat_context))
+ // clang-format on
+ basic_format_context {
+public:
+ using iterator = _OutIt;
+ using char_type = _CharT;
+ template <class _Tp>
+ using formatter_type = formatter<_Tp, _CharT>;
+
+ _LIBCPP_HIDE_FROM_ABI basic_format_arg<basic_format_context> arg(size_t __id) const noexcept {
+ return __args_.get(__id);
+ }
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+ _LIBCPP_HIDE_FROM_ABI std::locale locale() {
+ if (!__loc_)
+ __loc_ = std::locale{};
+ return *__loc_;
+ }
+# endif
+ _LIBCPP_HIDE_FROM_ABI iterator out() { return std::move(__out_it_); }
+ _LIBCPP_HIDE_FROM_ABI void advance_to(iterator __it) { __out_it_ = std::move(__it); }
+
+private:
+ iterator __out_it_;
+ basic_format_args<basic_format_context> __args_;
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+
+ // The Standard doesn't specify how the locale is stored.
+ // [format.context]/6
+ // std::locale locale();
+ // Returns: The locale passed to the formatting function if the latter
+ // takes one, and std::locale() otherwise.
+ // This is done by storing the locale of the constructor in this optional. If
+ // locale() is called and the optional has no value the value will be created.
+ // This allows the implementation to lazily create the locale.
+ // TODO FMT Validate whether lazy creation is the best solution.
+ optional<std::locale> __loc_;
+
+ template <class _OtherOutIt, class _OtherCharT>
+ friend _LIBCPP_HIDE_FROM_ABI basic_format_context<_OtherOutIt, _OtherCharT> __format_context_create(
+ _OtherOutIt, basic_format_args<basic_format_context<_OtherOutIt, _OtherCharT>>, optional<std::locale>&&);
+
+ // Note: the Standard doesn't specify the required constructors.
+ _LIBCPP_HIDE_FROM_ABI explicit basic_format_context(
+ _OutIt __out_it, basic_format_args<basic_format_context> __args, optional<std::locale>&& __loc)
+ : __out_it_(std::move(__out_it)), __args_(__args), __loc_(std::move(__loc)) {}
+# else
+ template <class _OtherOutIt, class _OtherCharT>
+ friend _LIBCPP_HIDE_FROM_ABI basic_format_context<_OtherOutIt, _OtherCharT>
+ __format_context_create(_OtherOutIt, basic_format_args<basic_format_context<_OtherOutIt, _OtherCharT>>);
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_format_context(_OutIt __out_it, basic_format_args<basic_format_context> __args)
+ : __out_it_(std::move(__out_it)), __args_(__args) {}
+# endif
+
+ basic_format_context(const basic_format_context&) = delete;
+ basic_format_context& operator=(const basic_format_context&) = delete;
+};
+
+// A specialization for __retarget_buffer
+//
+// See __retarget_buffer for the motivation for this specialization.
+//
+// This context holds a reference to the instance of the basic_format_context
+// that is retargeted. It converts a formatting argument when it is requested
+// during formatting. It is expected that the usage of the arguments is rare so
+// the lookups are not expected to be used often. An alternative would be to
+// convert all elements during construction.
+//
+// The elements of the retargets context are only used when an underlying
+// formatter uses a locale specific formatting or an formatting argument is
+// part for the format spec. For example
+// format("{:256:{}}", input, 8);
+// Here the width of an element in input is determined dynamically.
+// Note when the top-level element has no width the retargeting is not needed.
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS basic_format_context<typename __format::__retarget_buffer<_CharT>::__iterator, _CharT> {
+public:
+ using iterator = typename __format::__retarget_buffer<_CharT>::__iterator;
+ using char_type = _CharT;
+ template <class _Tp>
+ using formatter_type = formatter<_Tp, _CharT>;
+
+ template <class _Context>
+ _LIBCPP_HIDE_FROM_ABI explicit basic_format_context(iterator __out_it, _Context& __ctx)
+ : __out_it_(std::move(__out_it)),
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+ __loc_([](void* __c) { return static_cast<_Context*>(__c)->locale(); }),
+# endif
+ __ctx_(std::addressof(__ctx)),
+ __arg_([](void* __c, size_t __id) {
+ auto __visitor = [&](auto __arg) -> basic_format_arg<basic_format_context> {
+ if constexpr (same_as<decltype(__arg), monostate>)
+ return {};
+ else if constexpr (same_as<decltype(__arg), typename basic_format_arg<_Context>::handle>)
+ // At the moment it's not possible for formatting to use a re-targeted handle.
+ // TODO FMT add this when support is needed.
+ std::__throw_format_error("Re-targeting handle not supported");
+ else
+ return basic_format_arg<basic_format_context>{
+ __format::__determine_arg_t<basic_format_context, decltype(__arg)>(),
+ __basic_format_arg_value<basic_format_context>(__arg)};
+ };
+# if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+ return static_cast<_Context*>(__c)->arg(__id).visit(std::move(__visitor));
+# else
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ return std::visit_format_arg(std::move(__visitor), static_cast<_Context*>(__c)->arg(__id));
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+# endif // _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+ }) {
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_format_arg<basic_format_context> arg(size_t __id) const noexcept {
+ return __arg_(__ctx_, __id);
+ }
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+ _LIBCPP_HIDE_FROM_ABI std::locale locale() { return __loc_(__ctx_); }
+# endif
+ _LIBCPP_HIDE_FROM_ABI iterator out() { return std::move(__out_it_); }
+ _LIBCPP_HIDE_FROM_ABI void advance_to(iterator __it) { __out_it_ = std::move(__it); }
+
+private:
+ iterator __out_it_;
+
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+ std::locale (*__loc_)(void* __ctx);
+# endif
+
+ void* __ctx_;
+ basic_format_arg<basic_format_context> (*__arg_)(void* __ctx, size_t __id);
+};
+
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(basic_format_context);
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_FORMAT_CONTEXT_H
diff --git a/libcxx/include/__cxx03/__format/format_error.h b/libcxx/include/__cxx03/__format/format_error.h
new file mode 100644
index 00000000000000..ed40e395d6af72
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_error.h
@@ -0,0 +1,50 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_ERROR_H
+#define _LIBCPP___FORMAT_FORMAT_ERROR_H
+
+#include <__config>
+#include <__verbose_abort>
+#include <stdexcept>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wweak-vtables")
+class _LIBCPP_EXPORTED_FROM_ABI format_error : public runtime_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit format_error(const string& __s) : runtime_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI explicit format_error(const char* __s) : runtime_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI format_error(const format_error&) = default;
+ _LIBCPP_HIDE_FROM_ABI format_error& operator=(const format_error&) = default;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ ~format_error() noexcept override = default;
+};
+_LIBCPP_DIAGNOSTIC_POP
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_format_error(const char* __s) {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw format_error(__s);
+# else
+ _LIBCPP_VERBOSE_ABORT("format_error was thrown in -fno-exceptions mode with message \"%s\"", __s);
+# endif
+}
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMAT_ERROR_H
diff --git a/libcxx/include/__cxx03/__format/format_functions.h b/libcxx/include/__cxx03/__format/format_functions.h
new file mode 100644
index 00000000000000..d14b49aff14957
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_functions.h
@@ -0,0 +1,680 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_FUNCTIONS
+#define _LIBCPP___FORMAT_FORMAT_FUNCTIONS
+
+#include <__algorithm/clamp.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/buffer.h>
+#include <__format/format_arg.h>
+#include <__format/format_arg_store.h>
+#include <__format/format_args.h>
+#include <__format/format_context.h>
+#include <__format/format_error.h>
+#include <__format/format_parse_context.h>
+#include <__format/format_string.h>
+#include <__format/format_to_n_result.h>
+#include <__format/formatter.h>
+#include <__format/formatter_bool.h>
+#include <__format/formatter_char.h>
+#include <__format/formatter_floating_point.h>
+#include <__format/formatter_integer.h>
+#include <__format/formatter_pointer.h>
+#include <__format/formatter_string.h>
+#include <__format/parser_std_format_spec.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h> // iter_value_t
+#include <__variant/monostate.h>
+#include <array>
+#include <string>
+#include <string_view>
+
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+# include <__locale>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// TODO FMT Evaluate which templates should be external templates. This
+// improves the efficiency of the header. However since the header is still
+// under heavy development and not all classes are stable it makes no sense
+// to do this optimization now.
+
+using format_args = basic_format_args<format_context>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wformat_args = basic_format_args<wformat_context>;
+# endif
+
+template <class _Context = format_context, class... _Args>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI __format_arg_store<_Context, _Args...> make_format_args(_Args&... __args) {
+ return std::__format_arg_store<_Context, _Args...>(__args...);
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class... _Args>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI __format_arg_store<wformat_context, _Args...> make_wformat_args(_Args&... __args) {
+ return std::__format_arg_store<wformat_context, _Args...>(__args...);
+}
+# endif
+
+namespace __format {
+
+/// Helper class parse and handle argument.
+///
+/// When parsing a handle which is not enabled the code is ill-formed.
+/// This helper uses the parser of the appropriate formatter for the stored type.
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS __compile_time_handle {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __parse(_ParseContext& __ctx) const {
+ __parse_(__ctx);
+ }
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __enable() {
+ __parse_ = [](basic_format_parse_context<_CharT>& __ctx) {
+ formatter<_Tp, _CharT> __f;
+ __ctx.advance_to(__f.parse(__ctx));
+ };
+ }
+
+ // Before calling __parse the proper handler needs to be set with __enable.
+ // The default handler isn't a core constant expression.
+ _LIBCPP_HIDE_FROM_ABI constexpr __compile_time_handle()
+ : __parse_([](basic_format_parse_context<_CharT>&) { std::__throw_format_error("Not a handle"); }) {}
+
+private:
+ void (*__parse_)(basic_format_parse_context<_CharT>&);
+};
+
+// Dummy format_context only providing the parts used during constant
+// validation of the basic_format_string.
+template <class _CharT>
+struct _LIBCPP_TEMPLATE_VIS __compile_time_basic_format_context {
+public:
+ using char_type = _CharT;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __compile_time_basic_format_context(
+ const __arg_t* __args, const __compile_time_handle<_CharT>* __handles, size_t __size)
+ : __args_(__args), __handles_(__handles), __size_(__size) {}
+
+ // During the compile-time validation nothing needs to be written.
+ // Therefore all operations of this iterator are a NOP.
+ struct iterator {
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator& operator=(_CharT) { return *this; }
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator& operator*() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator operator++(int) { return *this; }
+ };
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __arg_t arg(size_t __id) const {
+ if (__id >= __size_)
+ std::__throw_format_error("The argument index value is too large for the number of arguments supplied");
+ return __args_[__id];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const __compile_time_handle<_CharT>& __handle(size_t __id) const {
+ if (__id >= __size_)
+ std::__throw_format_error("The argument index value is too large for the number of arguments supplied");
+ return __handles_[__id];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator out() { return {}; }
+ _LIBCPP_HIDE_FROM_ABI constexpr void advance_to(iterator) {}
+
+private:
+ const __arg_t* __args_;
+ const __compile_time_handle<_CharT>* __handles_;
+ size_t __size_;
+};
+
+// [format.string.std]/8
+// If { arg-idopt } is used in a width or precision, the value of the
+// corresponding formatting argument is used in its place. If the
+// corresponding formatting argument is not of standard signed or unsigned
+// integer type, or its value is negative for precision or non-positive for
+// width, an exception of type format_error is thrown.
+//
+// _HasPrecision does the formatter have a precision?
+template <class _CharT, class _Tp, bool _HasPrecision = false>
+_LIBCPP_HIDE_FROM_ABI constexpr void __compile_time_validate_argument(
+ basic_format_parse_context<_CharT>& __parse_ctx, __compile_time_basic_format_context<_CharT>& __ctx) {
+ auto __validate_type = [](__arg_t __type) {
+ // LWG3720 originally allowed "signed or unsigned integer types", however
+ // the final version explicitly changed it to "*standard* signed or unsigned
+ // integer types". It's trivial to use 128-bit integrals in libc++'s
+ // implementation, but other implementations may not implement it.
+ // (Using a width or precision, that does not fit in 64-bits, sounds very
+ // unlikely in real world code.)
+ switch (__type) {
+ case __arg_t::__int:
+ case __arg_t::__long_long:
+ case __arg_t::__unsigned:
+ case __arg_t::__unsigned_long_long:
+ return;
+
+ default:
+ std::__throw_format_error("Replacement argument isn't a standard signed or unsigned integer type");
+ }
+ };
+
+ formatter<_Tp, _CharT> __formatter;
+ __parse_ctx.advance_to(__formatter.parse(__parse_ctx));
+ if (__formatter.__parser_.__width_as_arg_)
+ __validate_type(__ctx.arg(__formatter.__parser_.__width_));
+
+ if constexpr (_HasPrecision)
+ if (__formatter.__parser_.__precision_as_arg_)
+ __validate_type(__ctx.arg(__formatter.__parser_.__precision_));
+}
+
+// This function is not user facing, so it can directly use the non-standard types of the "variant".
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr void __compile_time_visit_format_arg(
+ basic_format_parse_context<_CharT>& __parse_ctx,
+ __compile_time_basic_format_context<_CharT>& __ctx,
+ __arg_t __type) {
+ switch (__type) {
+ case __arg_t::__none:
+ std::__throw_format_error("Invalid argument");
+ case __arg_t::__boolean:
+ return __format::__compile_time_validate_argument<_CharT, bool>(__parse_ctx, __ctx);
+ case __arg_t::__char_type:
+ return __format::__compile_time_validate_argument<_CharT, _CharT>(__parse_ctx, __ctx);
+ case __arg_t::__int:
+ return __format::__compile_time_validate_argument<_CharT, int>(__parse_ctx, __ctx);
+ case __arg_t::__long_long:
+ return __format::__compile_time_validate_argument<_CharT, long long>(__parse_ctx, __ctx);
+ case __arg_t::__i128:
+# ifndef _LIBCPP_HAS_NO_INT128
+ return __format::__compile_time_validate_argument<_CharT, __int128_t>(__parse_ctx, __ctx);
+# else
+ std::__throw_format_error("Invalid argument");
+# endif
+ return;
+ case __arg_t::__unsigned:
+ return __format::__compile_time_validate_argument<_CharT, unsigned>(__parse_ctx, __ctx);
+ case __arg_t::__unsigned_long_long:
+ return __format::__compile_time_validate_argument<_CharT, unsigned long long>(__parse_ctx, __ctx);
+ case __arg_t::__u128:
+# ifndef _LIBCPP_HAS_NO_INT128
+ return __format::__compile_time_validate_argument<_CharT, __uint128_t>(__parse_ctx, __ctx);
+# else
+ std::__throw_format_error("Invalid argument");
+# endif
+ return;
+ case __arg_t::__float:
+ return __format::__compile_time_validate_argument<_CharT, float, true>(__parse_ctx, __ctx);
+ case __arg_t::__double:
+ return __format::__compile_time_validate_argument<_CharT, double, true>(__parse_ctx, __ctx);
+ case __arg_t::__long_double:
+ return __format::__compile_time_validate_argument<_CharT, long double, true>(__parse_ctx, __ctx);
+ case __arg_t::__const_char_type_ptr:
+ return __format::__compile_time_validate_argument<_CharT, const _CharT*, true>(__parse_ctx, __ctx);
+ case __arg_t::__string_view:
+ return __format::__compile_time_validate_argument<_CharT, basic_string_view<_CharT>, true>(__parse_ctx, __ctx);
+ case __arg_t::__ptr:
+ return __format::__compile_time_validate_argument<_CharT, const void*>(__parse_ctx, __ctx);
+ case __arg_t::__handle:
+ std::__throw_format_error("Handle should use __compile_time_validate_handle_argument");
+ }
+ std::__throw_format_error("Invalid argument");
+}
+
+template <contiguous_iterator _Iterator, class _ParseCtx, class _Ctx>
+_LIBCPP_HIDE_FROM_ABI constexpr _Iterator
+__handle_replacement_field(_Iterator __begin, _Iterator __end, _ParseCtx& __parse_ctx, _Ctx& __ctx) {
+ using _CharT = iter_value_t<_Iterator>;
+ __format::__parse_number_result __r = __format::__parse_arg_id(__begin, __end, __parse_ctx);
+
+ if (__r.__last == __end)
+ std::__throw_format_error("The argument index should end with a ':' or a '}'");
+
+ bool __parse = *__r.__last == _CharT(':');
+ switch (*__r.__last) {
+ case _CharT(':'):
+ // The arg-id has a format-specifier, advance the input to the format-spec.
+ __parse_ctx.advance_to(__r.__last + 1);
+ break;
+ case _CharT('}'):
+ // The arg-id has no format-specifier.
+ __parse_ctx.advance_to(__r.__last);
+ break;
+ default:
+ std::__throw_format_error("The argument index should end with a ':' or a '}'");
+ }
+
+ if constexpr (same_as<_Ctx, __compile_time_basic_format_context<_CharT>>) {
+ __arg_t __type = __ctx.arg(__r.__value);
+ if (__type == __arg_t::__none)
+ std::__throw_format_error("The argument index value is too large for the number of arguments supplied");
+ else if (__type == __arg_t::__handle)
+ __ctx.__handle(__r.__value).__parse(__parse_ctx);
+ else if (__parse)
+ __format::__compile_time_visit_format_arg(__parse_ctx, __ctx, __type);
+ } else
+ std::__visit_format_arg(
+ [&](auto __arg) {
+ if constexpr (same_as<decltype(__arg), monostate>)
+ std::__throw_format_error("The argument index value is too large for the number of arguments supplied");
+ else if constexpr (same_as<decltype(__arg), typename basic_format_arg<_Ctx>::handle>)
+ __arg.format(__parse_ctx, __ctx);
+ else {
+ formatter<decltype(__arg), _CharT> __formatter;
+ if (__parse)
+ __parse_ctx.advance_to(__formatter.parse(__parse_ctx));
+ __ctx.advance_to(__formatter.format(__arg, __ctx));
+ }
+ },
+ __ctx.arg(__r.__value));
+
+ __begin = __parse_ctx.begin();
+ if (__begin == __end || *__begin != _CharT('}'))
+ std::__throw_format_error("The replacement field misses a terminating '}'");
+
+ return ++__begin;
+}
+
+template <class _ParseCtx, class _Ctx>
+_LIBCPP_HIDE_FROM_ABI constexpr typename _Ctx::iterator __vformat_to(_ParseCtx&& __parse_ctx, _Ctx&& __ctx) {
+ using _CharT = typename _ParseCtx::char_type;
+ static_assert(same_as<typename _Ctx::char_type, _CharT>);
+
+ auto __begin = __parse_ctx.begin();
+ auto __end = __parse_ctx.end();
+ typename _Ctx::iterator __out_it = __ctx.out();
+ while (__begin != __end) {
+ switch (*__begin) {
+ case _CharT('{'):
+ ++__begin;
+ if (__begin == __end)
+ std::__throw_format_error("The format string terminates at a '{'");
+
+ if (*__begin != _CharT('{')) [[likely]] {
+ __ctx.advance_to(std::move(__out_it));
+ __begin = __format::__handle_replacement_field(__begin, __end, __parse_ctx, __ctx);
+ __out_it = __ctx.out();
+
+ // The output is written and __begin points to the next character. So
+ // start the next iteration.
+ continue;
+ }
+ // The string is an escape character.
+ break;
+
+ case _CharT('}'):
+ ++__begin;
+ if (__begin == __end || *__begin != _CharT('}'))
+ std::__throw_format_error("The format string contains an invalid escape sequence");
+
+ break;
+ }
+
+ // Copy the character to the output verbatim.
+ *__out_it++ = *__begin++;
+ }
+ return __out_it;
+}
+
+} // namespace __format
+
+# if _LIBCPP_STD_VER >= 26
+template <class _CharT>
+struct _LIBCPP_TEMPLATE_VIS __runtime_format_string {
+private:
+ basic_string_view<_CharT> __str_;
+
+ template <class _Cp, class... _Args>
+ friend struct _LIBCPP_TEMPLATE_VIS basic_format_string;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __runtime_format_string(basic_string_view<_CharT> __s) noexcept : __str_(__s) {}
+
+ __runtime_format_string(const __runtime_format_string&) = delete;
+ __runtime_format_string& operator=(const __runtime_format_string&) = delete;
+};
+
+_LIBCPP_HIDE_FROM_ABI inline __runtime_format_string<char> runtime_format(string_view __fmt) noexcept { return __fmt; }
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+_LIBCPP_HIDE_FROM_ABI inline __runtime_format_string<wchar_t> runtime_format(wstring_view __fmt) noexcept {
+ return __fmt;
+}
+# endif
+# endif //_LIBCPP_STD_VER >= 26
+
+template <class _CharT, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS basic_format_string {
+ template <class _Tp>
+ requires convertible_to<const _Tp&, basic_string_view<_CharT>>
+ consteval basic_format_string(const _Tp& __str) : __str_{__str} {
+ __format::__vformat_to(basic_format_parse_context<_CharT>{__str_, sizeof...(_Args)},
+ _Context{__types_.data(), __handles_.data(), sizeof...(_Args)});
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string_view<_CharT> get() const noexcept { return __str_; }
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI basic_format_string(__runtime_format_string<_CharT> __s) noexcept : __str_(__s.__str_) {}
+# endif
+
+private:
+ basic_string_view<_CharT> __str_;
+
+ using _Context = __format::__compile_time_basic_format_context<_CharT>;
+
+ static constexpr array<__format::__arg_t, sizeof...(_Args)> __types_{
+ __format::__determine_arg_t<_Context, remove_cvref_t<_Args>>()...};
+
+ static constexpr array<__format::__compile_time_handle<_CharT>, sizeof...(_Args)> __handles_{[] {
+ using _Tp = remove_cvref_t<_Args>;
+ __format::__compile_time_handle<_CharT> __handle;
+ if (__format::__determine_arg_t<_Context, _Tp>() == __format::__arg_t::__handle)
+ __handle.template __enable<_Tp>();
+
+ return __handle;
+ }()...};
+};
+
+template <class... _Args>
+using format_string = basic_format_string<char, type_identity_t<_Args>...>;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class... _Args>
+using wformat_string = basic_format_string<wchar_t, type_identity_t<_Args>...>;
+# endif
+
+template <class _OutIt, class _CharT, class _FormatOutIt>
+ requires(output_iterator<_OutIt, const _CharT&>)
+_LIBCPP_HIDE_FROM_ABI _OutIt __vformat_to(_OutIt __out_it,
+ basic_string_view<_CharT> __fmt,
+ basic_format_args<basic_format_context<_FormatOutIt, _CharT>> __args) {
+ if constexpr (same_as<_OutIt, _FormatOutIt>)
+ return std::__format::__vformat_to(
+ basic_format_parse_context{__fmt, __args.__size()}, std::__format_context_create(std::move(__out_it), __args));
+ else {
+ __format::__format_buffer<_OutIt, _CharT> __buffer{std::move(__out_it)};
+ std::__format::__vformat_to(basic_format_parse_context{__fmt, __args.__size()},
+ std::__format_context_create(__buffer.__make_output_iterator(), __args));
+ return std::move(__buffer).__out_it();
+ }
+}
+
+// The function is _LIBCPP_ALWAYS_INLINE since the compiler is bad at inlining
+// https://reviews.llvm.org/D110499#inline-1180704
+// TODO FMT Evaluate whether we want to file a Clang bug report regarding this.
+template <output_iterator<const char&> _OutIt>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _OutIt vformat_to(_OutIt __out_it, string_view __fmt, format_args __args) {
+ return std::__vformat_to(std::move(__out_it), __fmt, __args);
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <output_iterator<const wchar_t&> _OutIt>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _OutIt
+vformat_to(_OutIt __out_it, wstring_view __fmt, wformat_args __args) {
+ return std::__vformat_to(std::move(__out_it), __fmt, __args);
+}
+# endif
+
+template <output_iterator<const char&> _OutIt, class... _Args>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _OutIt
+format_to(_OutIt __out_it, format_string<_Args...> __fmt, _Args&&... __args) {
+ return std::vformat_to(std::move(__out_it), __fmt.get(), std::make_format_args(__args...));
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <output_iterator<const wchar_t&> _OutIt, class... _Args>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _OutIt
+format_to(_OutIt __out_it, wformat_string<_Args...> __fmt, _Args&&... __args) {
+ return std::vformat_to(std::move(__out_it), __fmt.get(), std::make_wformat_args(__args...));
+}
+# endif
+
+// TODO FMT This needs to be a template or std::to_chars(floating-point) availability markup
+// fires too eagerly, see http://llvm.org/PR61563.
+template <class = void>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE inline _LIBCPP_HIDE_FROM_ABI string vformat(string_view __fmt, format_args __args) {
+ string __res;
+ std::vformat_to(std::back_inserter(__res), __fmt, __args);
+ return __res;
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+// TODO FMT This needs to be a template or std::to_chars(floating-point) availability markup
+// fires too eagerly, see http://llvm.org/PR61563.
+template <class = void>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE inline _LIBCPP_HIDE_FROM_ABI wstring
+vformat(wstring_view __fmt, wformat_args __args) {
+ wstring __res;
+ std::vformat_to(std::back_inserter(__res), __fmt, __args);
+ return __res;
+}
+# endif
+
+template <class... _Args>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI string
+format(format_string<_Args...> __fmt, _Args&&... __args) {
+ return std::vformat(__fmt.get(), std::make_format_args(__args...));
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class... _Args>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI wstring
+format(wformat_string<_Args...> __fmt, _Args&&... __args) {
+ return std::vformat(__fmt.get(), std::make_wformat_args(__args...));
+}
+# endif
+
+template <class _Context, class _OutIt, class _CharT>
+_LIBCPP_HIDE_FROM_ABI format_to_n_result<_OutIt>
+__vformat_to_n(_OutIt __out_it,
+ iter_difference_t<_OutIt> __n,
+ basic_string_view<_CharT> __fmt,
+ basic_format_args<_Context> __args) {
+ __format::__format_to_n_buffer<_OutIt, _CharT> __buffer{std::move(__out_it), __n};
+ std::__format::__vformat_to(basic_format_parse_context{__fmt, __args.__size()},
+ std::__format_context_create(__buffer.__make_output_iterator(), __args));
+ return std::move(__buffer).__result();
+}
+
+template <output_iterator<const char&> _OutIt, class... _Args>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI format_to_n_result<_OutIt>
+format_to_n(_OutIt __out_it, iter_difference_t<_OutIt> __n, format_string<_Args...> __fmt, _Args&&... __args) {
+ return std::__vformat_to_n<format_context>(std::move(__out_it), __n, __fmt.get(), std::make_format_args(__args...));
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <output_iterator<const wchar_t&> _OutIt, class... _Args>
+_LIBCPP_HIDE_FROM_ABI format_to_n_result<_OutIt>
+format_to_n(_OutIt __out_it, iter_difference_t<_OutIt> __n, wformat_string<_Args...> __fmt, _Args&&... __args) {
+ return std::__vformat_to_n<wformat_context>(std::move(__out_it), __n, __fmt.get(), std::make_wformat_args(__args...));
+}
+# endif
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI size_t __vformatted_size(basic_string_view<_CharT> __fmt, auto __args) {
+ __format::__formatted_size_buffer<_CharT> __buffer;
+ std::__format::__vformat_to(basic_format_parse_context{__fmt, __args.__size()},
+ std::__format_context_create(__buffer.__make_output_iterator(), __args));
+ return std::move(__buffer).__result();
+}
+
+template <class... _Args>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI size_t
+formatted_size(format_string<_Args...> __fmt, _Args&&... __args) {
+ return std::__vformatted_size(__fmt.get(), basic_format_args{std::make_format_args(__args...)});
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class... _Args>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI size_t
+formatted_size(wformat_string<_Args...> __fmt, _Args&&... __args) {
+ return std::__vformatted_size(__fmt.get(), basic_format_args{std::make_wformat_args(__args...)});
+}
+# endif
+
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+
+template <class _OutIt, class _CharT, class _FormatOutIt>
+ requires(output_iterator<_OutIt, const _CharT&>)
+_LIBCPP_HIDE_FROM_ABI _OutIt __vformat_to(
+ _OutIt __out_it,
+ locale __loc,
+ basic_string_view<_CharT> __fmt,
+ basic_format_args<basic_format_context<_FormatOutIt, _CharT>> __args) {
+ if constexpr (same_as<_OutIt, _FormatOutIt>)
+ return std::__format::__vformat_to(basic_format_parse_context{__fmt, __args.__size()},
+ std::__format_context_create(std::move(__out_it), __args, std::move(__loc)));
+ else {
+ __format::__format_buffer<_OutIt, _CharT> __buffer{std::move(__out_it)};
+ std::__format::__vformat_to(
+ basic_format_parse_context{__fmt, __args.__size()},
+ std::__format_context_create(__buffer.__make_output_iterator(), __args, std::move(__loc)));
+ return std::move(__buffer).__out_it();
+ }
+}
+
+template <output_iterator<const char&> _OutIt>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _OutIt
+vformat_to(_OutIt __out_it, locale __loc, string_view __fmt, format_args __args) {
+ return std::__vformat_to(std::move(__out_it), std::move(__loc), __fmt, __args);
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <output_iterator<const wchar_t&> _OutIt>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _OutIt
+vformat_to(_OutIt __out_it, locale __loc, wstring_view __fmt, wformat_args __args) {
+ return std::__vformat_to(std::move(__out_it), std::move(__loc), __fmt, __args);
+}
+# endif
+
+template <output_iterator<const char&> _OutIt, class... _Args>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _OutIt
+format_to(_OutIt __out_it, locale __loc, format_string<_Args...> __fmt, _Args&&... __args) {
+ return std::vformat_to(std::move(__out_it), std::move(__loc), __fmt.get(), std::make_format_args(__args...));
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <output_iterator<const wchar_t&> _OutIt, class... _Args>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _OutIt
+format_to(_OutIt __out_it, locale __loc, wformat_string<_Args...> __fmt, _Args&&... __args) {
+ return std::vformat_to(std::move(__out_it), std::move(__loc), __fmt.get(), std::make_wformat_args(__args...));
+}
+# endif
+
+// TODO FMT This needs to be a template or std::to_chars(floating-point) availability markup
+// fires too eagerly, see http://llvm.org/PR61563.
+template <class = void>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE inline _LIBCPP_HIDE_FROM_ABI string
+vformat(locale __loc, string_view __fmt, format_args __args) {
+ string __res;
+ std::vformat_to(std::back_inserter(__res), std::move(__loc), __fmt, __args);
+ return __res;
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+// TODO FMT This needs to be a template or std::to_chars(floating-point) availability markup
+// fires too eagerly, see http://llvm.org/PR61563.
+template <class = void>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE inline _LIBCPP_HIDE_FROM_ABI wstring
+vformat(locale __loc, wstring_view __fmt, wformat_args __args) {
+ wstring __res;
+ std::vformat_to(std::back_inserter(__res), std::move(__loc), __fmt, __args);
+ return __res;
+}
+# endif
+
+template <class... _Args>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI string
+format(locale __loc, format_string<_Args...> __fmt, _Args&&... __args) {
+ return std::vformat(std::move(__loc), __fmt.get(), std::make_format_args(__args...));
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class... _Args>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI wstring
+format(locale __loc, wformat_string<_Args...> __fmt, _Args&&... __args) {
+ return std::vformat(std::move(__loc), __fmt.get(), std::make_wformat_args(__args...));
+}
+# endif
+
+template <class _Context, class _OutIt, class _CharT>
+_LIBCPP_HIDE_FROM_ABI format_to_n_result<_OutIt> __vformat_to_n(
+ _OutIt __out_it,
+ iter_difference_t<_OutIt> __n,
+ locale __loc,
+ basic_string_view<_CharT> __fmt,
+ basic_format_args<_Context> __args) {
+ __format::__format_to_n_buffer<_OutIt, _CharT> __buffer{std::move(__out_it), __n};
+ std::__format::__vformat_to(
+ basic_format_parse_context{__fmt, __args.__size()},
+ std::__format_context_create(__buffer.__make_output_iterator(), __args, std::move(__loc)));
+ return std::move(__buffer).__result();
+}
+
+template <output_iterator<const char&> _OutIt, class... _Args>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI format_to_n_result<_OutIt> format_to_n(
+ _OutIt __out_it, iter_difference_t<_OutIt> __n, locale __loc, format_string<_Args...> __fmt, _Args&&... __args) {
+ return std::__vformat_to_n<format_context>(
+ std::move(__out_it), __n, std::move(__loc), __fmt.get(), std::make_format_args(__args...));
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <output_iterator<const wchar_t&> _OutIt, class... _Args>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI format_to_n_result<_OutIt> format_to_n(
+ _OutIt __out_it, iter_difference_t<_OutIt> __n, locale __loc, wformat_string<_Args...> __fmt, _Args&&... __args) {
+ return std::__vformat_to_n<wformat_context>(
+ std::move(__out_it), __n, std::move(__loc), __fmt.get(), std::make_wformat_args(__args...));
+}
+# endif
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI size_t __vformatted_size(locale __loc, basic_string_view<_CharT> __fmt, auto __args) {
+ __format::__formatted_size_buffer<_CharT> __buffer;
+ std::__format::__vformat_to(
+ basic_format_parse_context{__fmt, __args.__size()},
+ std::__format_context_create(__buffer.__make_output_iterator(), __args, std::move(__loc)));
+ return std::move(__buffer).__result();
+}
+
+template <class... _Args>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI size_t
+formatted_size(locale __loc, format_string<_Args...> __fmt, _Args&&... __args) {
+ return std::__vformatted_size(std::move(__loc), __fmt.get(), basic_format_args{std::make_format_args(__args...)});
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class... _Args>
+[[nodiscard]] _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI size_t
+formatted_size(locale __loc, wformat_string<_Args...> __fmt, _Args&&... __args) {
+ return std::__vformatted_size(std::move(__loc), __fmt.get(), basic_format_args{std::make_wformat_args(__args...)});
+}
+# endif
+
+# endif // _LIBCPP_HAS_NO_LOCALIZATION
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_FORMAT_FUNCTIONS
diff --git a/libcxx/include/__cxx03/__format/format_parse_context.h b/libcxx/include/__cxx03/__format/format_parse_context.h
new file mode 100644
index 00000000000000..aefcd5497f3b9b
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_parse_context.h
@@ -0,0 +1,105 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_PARSE_CONTEXT_H
+#define _LIBCPP___FORMAT_FORMAT_PARSE_CONTEXT_H
+
+#include <__config>
+#include <__format/format_error.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS basic_format_parse_context {
+public:
+ using char_type = _CharT;
+ using const_iterator = typename basic_string_view<_CharT>::const_iterator;
+ using iterator = const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit basic_format_parse_context(
+ basic_string_view<_CharT> __fmt, size_t __num_args = 0) noexcept
+ : __begin_(__fmt.begin()),
+ __end_(__fmt.end()),
+ __indexing_(__unknown),
+ __next_arg_id_(0),
+ __num_args_(__num_args) {}
+
+ basic_format_parse_context(const basic_format_parse_context&) = delete;
+ basic_format_parse_context& operator=(const basic_format_parse_context&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const_iterator begin() const noexcept { return __begin_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const_iterator end() const noexcept { return __end_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr void advance_to(const_iterator __it) { __begin_ = __it; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr size_t next_arg_id() {
+ if (__indexing_ == __manual)
+ std::__throw_format_error("Using automatic argument numbering in manual argument numbering mode");
+
+ if (__indexing_ == __unknown)
+ __indexing_ = __automatic;
+
+ // Throws an exception to make the expression a non core constant
+ // expression as required by:
+ // [format.parse.ctx]/8
+ // Remarks: Let cur-arg-id be the value of next_arg_id_ prior to this
+ // call. Call expressions where cur-arg-id >= num_args_ is true are not
+ // core constant expressions (7.7 [expr.const]).
+ // Note: the Throws clause [format.parse.ctx]/9 doesn't specify the
+ // behavior when id >= num_args_.
+ if (is_constant_evaluated() && __next_arg_id_ >= __num_args_)
+ std::__throw_format_error("Argument index outside the valid range");
+
+ return __next_arg_id_++;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr void check_arg_id(size_t __id) {
+ if (__indexing_ == __automatic)
+ std::__throw_format_error("Using manual argument numbering in automatic argument numbering mode");
+
+ if (__indexing_ == __unknown)
+ __indexing_ = __manual;
+
+ // Throws an exception to make the expression a non core constant
+ // expression as required by:
+ // [format.parse.ctx]/11
+ // Remarks: Call expressions where id >= num_args_ are not core constant
+ // expressions ([expr.const]).
+ // Note: the Throws clause [format.parse.ctx]/10 doesn't specify the
+ // behavior when id >= num_args_.
+ if (is_constant_evaluated() && __id >= __num_args_)
+ std::__throw_format_error("Argument index outside the valid range");
+ }
+
+private:
+ iterator __begin_;
+ iterator __end_;
+ enum _Indexing { __unknown, __manual, __automatic };
+ _Indexing __indexing_;
+ size_t __next_arg_id_;
+ size_t __num_args_;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(basic_format_parse_context);
+
+using format_parse_context = basic_format_parse_context<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wformat_parse_context = basic_format_parse_context<wchar_t>;
+# endif
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMAT_PARSE_CONTEXT_H
diff --git a/libcxx/include/__cxx03/__format/format_string.h b/libcxx/include/__cxx03/__format/format_string.h
new file mode 100644
index 00000000000000..bdf3cff7f49b18
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_string.h
@@ -0,0 +1,160 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_STRING_H
+#define _LIBCPP___FORMAT_FORMAT_STRING_H
+
+#include <__assert>
+#include <__config>
+#include <__format/format_error.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h> // iter_value_t
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __format {
+
+template <contiguous_iterator _Iterator>
+struct _LIBCPP_TEMPLATE_VIS __parse_number_result {
+ _Iterator __last;
+ uint32_t __value;
+};
+
+template <contiguous_iterator _Iterator>
+__parse_number_result(_Iterator, uint32_t) -> __parse_number_result<_Iterator>;
+
+template <contiguous_iterator _Iterator>
+_LIBCPP_HIDE_FROM_ABI constexpr __parse_number_result<_Iterator> __parse_number(_Iterator __begin, _Iterator __end);
+
+/**
+ * The maximum value of a numeric argument.
+ *
+ * This is used for:
+ * * arg-id
+ * * width as value or arg-id.
+ * * precision as value or arg-id.
+ *
+ * The value is compatible with the maximum formatting width and precision
+ * using the `%*` syntax on a 32-bit system.
+ */
+inline constexpr uint32_t __number_max = INT32_MAX;
+
+namespace __detail {
+template <contiguous_iterator _Iterator>
+_LIBCPP_HIDE_FROM_ABI constexpr __parse_number_result<_Iterator>
+__parse_zero(_Iterator __begin, _Iterator, auto& __parse_ctx) {
+ __parse_ctx.check_arg_id(0);
+ return {++__begin, 0}; // can never be larger than the maximum.
+}
+
+template <contiguous_iterator _Iterator>
+_LIBCPP_HIDE_FROM_ABI constexpr __parse_number_result<_Iterator>
+__parse_automatic(_Iterator __begin, _Iterator, auto& __parse_ctx) {
+ size_t __value = __parse_ctx.next_arg_id();
+ _LIBCPP_ASSERT_UNCATEGORIZED(__value <= __number_max, "Compilers don't support this number of arguments");
+
+ return {__begin, uint32_t(__value)};
+}
+
+template <contiguous_iterator _Iterator>
+_LIBCPP_HIDE_FROM_ABI constexpr __parse_number_result<_Iterator>
+__parse_manual(_Iterator __begin, _Iterator __end, auto& __parse_ctx) {
+ __parse_number_result<_Iterator> __r = __format::__parse_number(__begin, __end);
+ __parse_ctx.check_arg_id(__r.__value);
+ return __r;
+}
+
+} // namespace __detail
+
+/**
+ * Parses a number.
+ *
+ * The number is used for the 31-bit values @em width and @em precision. This
+ * allows a maximum value of 2147483647.
+ */
+template <contiguous_iterator _Iterator>
+_LIBCPP_HIDE_FROM_ABI constexpr __parse_number_result<_Iterator>
+__parse_number(_Iterator __begin, _Iterator __end_input) {
+ using _CharT = iter_value_t<_Iterator>;
+ static_assert(__format::__number_max == INT32_MAX, "The algorithm is implemented based on this value.");
+ /*
+ * Limit the input to 9 digits, otherwise we need two checks during every
+ * iteration:
+ * - Are we at the end of the input?
+ * - Does the value exceed width of an uint32_t? (Switching to uint64_t would
+ * have the same issue, but with a higher maximum.)
+ */
+ _Iterator __end = __end_input - __begin > 9 ? __begin + 9 : __end_input;
+ uint32_t __value = *__begin - _CharT('0');
+ while (++__begin != __end) {
+ if (*__begin < _CharT('0') || *__begin > _CharT('9'))
+ return {__begin, __value};
+
+ __value = __value * 10 + *__begin - _CharT('0');
+ }
+
+ if (__begin != __end_input && *__begin >= _CharT('0') && *__begin <= _CharT('9')) {
+ /*
+ * There are more than 9 digits, do additional validations:
+ * - Does the 10th digit exceed the maximum allowed value?
+ * - Are there more than 10 digits?
+ * (More than 10 digits always overflows the maximum.)
+ */
+ uint64_t __v = uint64_t(__value) * 10 + *__begin++ - _CharT('0');
+ if (__v > __number_max || (__begin != __end_input && *__begin >= _CharT('0') && *__begin <= _CharT('9')))
+ std::__throw_format_error("The numeric value of the format specifier is too large");
+
+ __value = __v;
+ }
+
+ return {__begin, __value};
+}
+
+/**
+ * Multiplexer for all parse functions.
+ *
+ * The parser will return a pointer beyond the last consumed character. This
+ * should be the closing '}' of the arg-id.
+ */
+template <contiguous_iterator _Iterator>
+_LIBCPP_HIDE_FROM_ABI constexpr __parse_number_result<_Iterator>
+__parse_arg_id(_Iterator __begin, _Iterator __end, auto& __parse_ctx) {
+ using _CharT = iter_value_t<_Iterator>;
+ switch (*__begin) {
+ case _CharT('0'):
+ return __detail::__parse_zero(__begin, __end, __parse_ctx);
+
+ case _CharT(':'):
+ // This case is conditionally valid. It's allowed in an arg-id in the
+ // replacement-field, but not in the std-format-spec. The caller can
+ // provide a better diagnostic, so accept it here unconditionally.
+ case _CharT('}'):
+ return __detail::__parse_automatic(__begin, __end, __parse_ctx);
+ }
+ if (*__begin < _CharT('0') || *__begin > _CharT('9'))
+ std::__throw_format_error("The argument index starts with an invalid character");
+
+ return __detail::__parse_manual(__begin, __end, __parse_ctx);
+}
+
+} // namespace __format
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMAT_STRING_H
diff --git a/libcxx/include/__cxx03/__format/format_to_n_result.h b/libcxx/include/__cxx03/__format/format_to_n_result.h
new file mode 100644
index 00000000000000..6f30546dec081c
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/format_to_n_result.h
@@ -0,0 +1,35 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMAT_TO_N_RESULT_H
+#define _LIBCPP___FORMAT_FORMAT_TO_N_RESULT_H
+
+#include <__config>
+#include <__iterator/incrementable_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _OutIt>
+struct _LIBCPP_TEMPLATE_VIS format_to_n_result {
+ _OutIt out;
+ iter_difference_t<_OutIt> size;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(format_to_n_result);
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMAT_TO_N_RESULT_H
diff --git a/libcxx/include/__cxx03/__format/formatter.h b/libcxx/include/__cxx03/__format/formatter.h
new file mode 100644
index 00000000000000..e2f418f936ee10
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_H
+#define _LIBCPP___FORMAT_FORMATTER_H
+
+#include <__config>
+#include <__fwd/format.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+/// The default formatter template.
+///
+/// [format.formatter.spec]/5
+/// If F is a disabled specialization of formatter, these values are false:
+/// - is_default_constructible_v<F>,
+/// - is_copy_constructible_v<F>,
+/// - is_move_constructible_v<F>,
+/// - is_copy_assignable<F>, and
+/// - is_move_assignable<F>.
+template <class _Tp, class _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter {
+ formatter() = delete;
+ formatter(const formatter&) = delete;
+ formatter& operator=(const formatter&) = delete;
+};
+
+# if _LIBCPP_STD_VER >= 23
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr void __set_debug_format(_Tp& __formatter) {
+ if constexpr (requires { __formatter.set_debug_format(); })
+ __formatter.set_debug_format();
+}
+
+# endif // _LIBCPP_STD_VER >= 23
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMATTER_H
diff --git a/libcxx/include/__cxx03/__format/formatter_bool.h b/libcxx/include/__cxx03/__format/formatter_bool.h
new file mode 100644
index 00000000000000..17dc69541e8fe1
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_bool.h
@@ -0,0 +1,76 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_BOOL_H
+#define _LIBCPP___FORMAT_FORMATTER_BOOL_H
+
+#include <__algorithm/copy.h>
+#include <__assert>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/formatter_integral.h>
+#include <__format/parser_std_format_spec.h>
+#include <__utility/unreachable.h>
+
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+# include <__locale>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<bool, _CharT> {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_integral);
+ __format_spec::__process_parsed_bool(__parser_, "a bool");
+ return __result;
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(bool __value, _FormatContext& __ctx) const {
+ switch (__parser_.__type_) {
+ case __format_spec::__type::__default:
+ case __format_spec::__type::__string:
+ return __formatter::__format_bool(__value, __ctx, __parser_.__get_parsed_std_specifications(__ctx));
+
+ case __format_spec::__type::__binary_lower_case:
+ case __format_spec::__type::__binary_upper_case:
+ case __format_spec::__type::__octal:
+ case __format_spec::__type::__decimal:
+ case __format_spec::__type::__hexadecimal_lower_case:
+ case __format_spec::__type::__hexadecimal_upper_case:
+ // Promotes bool to an integral type. This reduces the number of
+ // instantiations of __format_integer reducing code size.
+ return __formatter::__format_integer(
+ static_cast<unsigned>(__value), __ctx, __parser_.__get_parsed_std_specifications(__ctx));
+
+ default:
+ _LIBCPP_ASSERT_INTERNAL(false, "The parse function should have validated the type");
+ __libcpp_unreachable();
+ }
+ }
+
+ __format_spec::__parser<_CharT> __parser_;
+};
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMATTER_BOOL_H
diff --git a/libcxx/include/__cxx03/__format/formatter_char.h b/libcxx/include/__cxx03/__format/formatter_char.h
new file mode 100644
index 00000000000000..d33e84368a7650
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_char.h
@@ -0,0 +1,93 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_CHAR_H
+#define _LIBCPP___FORMAT_FORMATTER_CHAR_H
+
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/formatter_integral.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <__format/write_escaped.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/make_unsigned.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS __formatter_char {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_integral);
+ __format_spec::__process_parsed_char(__parser_, "a character");
+ return __result;
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(_CharT __value, _FormatContext& __ctx) const {
+ if (__parser_.__type_ == __format_spec::__type::__default || __parser_.__type_ == __format_spec::__type::__char)
+ return __formatter::__format_char(__value, __ctx.out(), __parser_.__get_parsed_std_specifications(__ctx));
+
+# if _LIBCPP_STD_VER >= 23
+ if (__parser_.__type_ == __format_spec::__type::__debug)
+ return __formatter::__format_escaped_char(__value, __ctx.out(), __parser_.__get_parsed_std_specifications(__ctx));
+# endif
+
+ if constexpr (sizeof(_CharT) <= sizeof(unsigned))
+ return __formatter::__format_integer(
+ static_cast<unsigned>(static_cast<make_unsigned_t<_CharT>>(__value)),
+ __ctx,
+ __parser_.__get_parsed_std_specifications(__ctx));
+ else
+ return __formatter::__format_integer(
+ static_cast<make_unsigned_t<_CharT>>(__value), __ctx, __parser_.__get_parsed_std_specifications(__ctx));
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(char __value, _FormatContext& __ctx) const
+ requires(same_as<_CharT, wchar_t>)
+ {
+ return format(static_cast<wchar_t>(static_cast<unsigned char>(__value)), __ctx);
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI constexpr void set_debug_format() { __parser_.__type_ = __format_spec::__type::__debug; }
+# endif
+
+ __format_spec::__parser<_CharT> __parser_;
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS formatter<char, char> : public __formatter_char<char> {};
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+struct _LIBCPP_TEMPLATE_VIS formatter<char, wchar_t> : public __formatter_char<wchar_t> {};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS formatter<wchar_t, wchar_t> : public __formatter_char<wchar_t> {};
+
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMATTER_CHAR_H
diff --git a/libcxx/include/__cxx03/__format/formatter_floating_point.h b/libcxx/include/__cxx03/__format/formatter_floating_point.h
new file mode 100644
index 00000000000000..fa42ba203b0b5e
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_floating_point.h
@@ -0,0 +1,783 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_FLOATING_POINT_H
+#define _LIBCPP___FORMAT_FORMATTER_FLOATING_POINT_H
+
+#include <__algorithm/copy_n.h>
+#include <__algorithm/find.h>
+#include <__algorithm/max.h>
+#include <__algorithm/min.h>
+#include <__algorithm/rotate.h>
+#include <__algorithm/transform.h>
+#include <__assert>
+#include <__charconv/chars_format.h>
+#include <__charconv/to_chars_floating_point.h>
+#include <__charconv/to_chars_result.h>
+#include <__concepts/arithmetic.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/formatter_integral.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <__iterator/concepts.h>
+#include <__memory/allocator.h>
+#include <__system_error/errc.h>
+#include <__type_traits/conditional.h>
+#include <__utility/move.h>
+#include <__utility/unreachable.h>
+#include <cmath>
+#include <cstddef>
+
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+# include <__locale>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __formatter {
+
+template <floating_point _Tp>
+_LIBCPP_HIDE_FROM_ABI char* __to_buffer(char* __first, char* __last, _Tp __value) {
+ to_chars_result __r = std::to_chars(__first, __last, __value);
+ _LIBCPP_ASSERT_INTERNAL(__r.ec == errc(0), "Internal buffer too small");
+ return __r.ptr;
+}
+
+template <floating_point _Tp>
+_LIBCPP_HIDE_FROM_ABI char* __to_buffer(char* __first, char* __last, _Tp __value, chars_format __fmt) {
+ to_chars_result __r = std::to_chars(__first, __last, __value, __fmt);
+ _LIBCPP_ASSERT_INTERNAL(__r.ec == errc(0), "Internal buffer too small");
+ return __r.ptr;
+}
+
+template <floating_point _Tp>
+_LIBCPP_HIDE_FROM_ABI char* __to_buffer(char* __first, char* __last, _Tp __value, chars_format __fmt, int __precision) {
+ to_chars_result __r = std::to_chars(__first, __last, __value, __fmt, __precision);
+ _LIBCPP_ASSERT_INTERNAL(__r.ec == errc(0), "Internal buffer too small");
+ return __r.ptr;
+}
+
+// https://en.cppreference.com/w/cpp/language/types#cite_note-1
+// float min subnormal: +/-0x1p-149 max: +/- 3.402,823,4 10^38
+// double min subnormal: +/-0x1p-1074 max +/- 1.797,693,134,862,315,7 10^308
+// long double (x86) min subnormal: +/-0x1p-16446 max: +/- 1.189,731,495,357,231,765,021 10^4932
+//
+// The maximum number of digits required for the integral part is based on the
+// maximum's value power of 10. Every power of 10 requires one additional
+// decimal digit.
+// The maximum number of digits required for the fractional part is based on
+// the minimal subnormal hexadecimal output's power of 10. Every division of a
+// fraction's binary 1 by 2, requires one additional decimal digit.
+//
+// The maximum size of a formatted value depends on the selected output format.
+// Ignoring the fact the format string can request a precision larger than the
+// values maximum required, these values are:
+//
+// sign 1 code unit
+// __max_integral
+// radix point 1 code unit
+// __max_fractional
+// exponent character 1 code unit
+// sign 1 code unit
+// __max_fractional_value
+// -----------------------------------
+// total 4 code units extra required.
+//
+// TODO FMT Optimize the storage to avoid storing digits that are known to be zero.
+// https://www.exploringbinary.com/maximum-number-of-decimal-digits-in-binary-floating-point-numbers/
+
+// TODO FMT Add long double specialization when to_chars has proper long double support.
+template <class _Tp>
+struct __traits;
+
+template <floating_point _Fp>
+_LIBCPP_HIDE_FROM_ABI constexpr size_t __float_buffer_size(int __precision) {
+ using _Traits = __traits<_Fp>;
+ return 4 + _Traits::__max_integral + __precision + _Traits::__max_fractional_value;
+}
+
+template <>
+struct __traits<float> {
+ static constexpr int __max_integral = 38;
+ static constexpr int __max_fractional = 149;
+ static constexpr int __max_fractional_value = 3;
+ static constexpr size_t __stack_buffer_size = 256;
+
+ static constexpr int __hex_precision_digits = 3;
+};
+
+template <>
+struct __traits<double> {
+ static constexpr int __max_integral = 308;
+ static constexpr int __max_fractional = 1074;
+ static constexpr int __max_fractional_value = 4;
+ static constexpr size_t __stack_buffer_size = 1024;
+
+ static constexpr int __hex_precision_digits = 4;
+};
+
+/// Helper class to store the conversion buffer.
+///
+/// Depending on the maximum size required for a value, the buffer is allocated
+/// on the stack or the heap.
+template <floating_point _Fp>
+class _LIBCPP_TEMPLATE_VIS __float_buffer {
+ using _Traits = __traits<_Fp>;
+
+public:
+ // TODO FMT Improve this constructor to do a better estimate.
+ // When using a scientific formatting with a precision of 6 a stack buffer
+ // will always suffice. At the moment that isn't important since floats and
+ // doubles use a stack buffer, unless the precision used in the format string
+ // is large.
+ // When supporting long doubles the __max_integral part becomes 4932 which
+ // may be too much for some platforms. For these cases a better estimate is
+ // required.
+ explicit _LIBCPP_HIDE_FROM_ABI __float_buffer(int __precision)
+ : __precision_(__precision != -1 ? __precision : _Traits::__max_fractional) {
+ // When the precision is larger than _Traits::__max_fractional the digits in
+ // the range (_Traits::__max_fractional, precision] will contain the value
+ // zero. There's no need to request to_chars to write these zeros:
+ // - When the value is large a temporary heap buffer needs to be allocated.
+ // - When to_chars writes the values they need to be "copied" to the output:
+ // - char: std::fill on the output iterator is faster than std::copy.
+ // - wchar_t: same argument as char, but additional std::copy won't work.
+ // The input is always a char buffer, so every char in the buffer needs
+ // to be converted from a char to a wchar_t.
+ if (__precision_ > _Traits::__max_fractional) {
+ __num_trailing_zeros_ = __precision_ - _Traits::__max_fractional;
+ __precision_ = _Traits::__max_fractional;
+ }
+
+ __size_ = __formatter::__float_buffer_size<_Fp>(__precision_);
+ if (__size_ > _Traits::__stack_buffer_size)
+ // The allocated buffer's contents don't need initialization.
+ __begin_ = allocator<char>{}.allocate(__size_);
+ else
+ __begin_ = __buffer_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~__float_buffer() {
+ if (__size_ > _Traits::__stack_buffer_size)
+ allocator<char>{}.deallocate(__begin_, __size_);
+ }
+ _LIBCPP_HIDE_FROM_ABI __float_buffer(const __float_buffer&) = delete;
+ _LIBCPP_HIDE_FROM_ABI __float_buffer& operator=(const __float_buffer&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI char* begin() const { return __begin_; }
+ _LIBCPP_HIDE_FROM_ABI char* end() const { return __begin_ + __size_; }
+
+ _LIBCPP_HIDE_FROM_ABI int __precision() const { return __precision_; }
+ _LIBCPP_HIDE_FROM_ABI int __num_trailing_zeros() const { return __num_trailing_zeros_; }
+ _LIBCPP_HIDE_FROM_ABI void __remove_trailing_zeros() { __num_trailing_zeros_ = 0; }
+ _LIBCPP_HIDE_FROM_ABI void __add_trailing_zeros(int __zeros) { __num_trailing_zeros_ += __zeros; }
+
+private:
+ int __precision_;
+ int __num_trailing_zeros_{0};
+ size_t __size_;
+ char* __begin_;
+ char __buffer_[_Traits::__stack_buffer_size];
+};
+
+struct __float_result {
+ /// Points at the beginning of the integral part in the buffer.
+ ///
+ /// When there's no sign character this points at the start of the buffer.
+ char* __integral;
+
+ /// Points at the radix point, when not present it's the same as \ref __last.
+ char* __radix_point;
+
+ /// Points at the exponent character, when not present it's the same as \ref __last.
+ char* __exponent;
+
+ /// Points beyond the last written element in the buffer.
+ char* __last;
+};
+
+/// Finds the position of the exponent character 'e' at the end of the buffer.
+///
+/// Assuming there is an exponent the input will terminate with
+/// eSdd and eSdddd (S = sign, d = digit)
+///
+/// \returns a pointer to the exponent or __last when not found.
+constexpr inline _LIBCPP_HIDE_FROM_ABI char* __find_exponent(char* __first, char* __last) {
+ ptrdiff_t __size = __last - __first;
+ if (__size >= 4) {
+ __first = __last - std::min(__size, ptrdiff_t(6));
+ for (; __first != __last - 3; ++__first) {
+ if (*__first == 'e')
+ return __first;
+ }
+ }
+ return __last;
+}
+
+template <class _Fp, class _Tp>
+_LIBCPP_HIDE_FROM_ABI __float_result
+__format_buffer_default(const __float_buffer<_Fp>& __buffer, _Tp __value, char* __integral) {
+ __float_result __result;
+ __result.__integral = __integral;
+ __result.__last = __formatter::__to_buffer(__integral, __buffer.end(), __value);
+
+ __result.__exponent = __formatter::__find_exponent(__result.__integral, __result.__last);
+
+ // Constrains:
+ // - There's at least one decimal digit before the radix point.
+ // - The radix point, when present, is placed before the exponent.
+ __result.__radix_point = std::find(__result.__integral + 1, __result.__exponent, '.');
+
+ // When the radix point isn't found its position is the exponent instead of
+ // __result.__last.
+ if (__result.__radix_point == __result.__exponent)
+ __result.__radix_point = __result.__last;
+
+ // clang-format off
+ _LIBCPP_ASSERT_INTERNAL((__result.__integral != __result.__last) &&
+ (__result.__radix_point == __result.__last || *__result.__radix_point == '.') &&
+ (__result.__exponent == __result.__last || *__result.__exponent == 'e'),
+ "Post-condition failure.");
+ // clang-format on
+
+ return __result;
+}
+
+template <class _Fp, class _Tp>
+_LIBCPP_HIDE_FROM_ABI __float_result __format_buffer_hexadecimal_lower_case(
+ const __float_buffer<_Fp>& __buffer, _Tp __value, int __precision, char* __integral) {
+ __float_result __result;
+ __result.__integral = __integral;
+ if (__precision == -1)
+ __result.__last = __formatter::__to_buffer(__integral, __buffer.end(), __value, chars_format::hex);
+ else
+ __result.__last = __formatter::__to_buffer(__integral, __buffer.end(), __value, chars_format::hex, __precision);
+
+ // H = one or more hex-digits
+ // S = sign
+ // D = one or more decimal-digits
+ // When the fractional part is zero and no precision the output is 0p+0
+ // else the output is 0.HpSD
+ // So testing the second position can differentiate between these two cases.
+ char* __first = __integral + 1;
+ if (*__first == '.') {
+ __result.__radix_point = __first;
+ // One digit is the minimum
+ // 0.hpSd
+ // ^-- last
+ // ^---- integral = end of search
+ // ^-------- start of search
+ // 0123456
+ //
+ // Four digits is the maximum
+ // 0.hpSdddd
+ // ^-- last
+ // ^---- integral = end of search
+ // ^-------- start of search
+ // 0123456789
+ static_assert(__traits<_Fp>::__hex_precision_digits <= 4, "Guard against possible underflow.");
+
+ char* __last = __result.__last - 2;
+ __first = __last - __traits<_Fp>::__hex_precision_digits;
+ __result.__exponent = std::find(__first, __last, 'p');
+ } else {
+ __result.__radix_point = __result.__last;
+ __result.__exponent = __first;
+ }
+
+ // clang-format off
+ _LIBCPP_ASSERT_INTERNAL((__result.__integral != __result.__last) &&
+ (__result.__radix_point == __result.__last || *__result.__radix_point == '.') &&
+ (__result.__exponent != __result.__last && *__result.__exponent == 'p'),
+ "Post-condition failure.");
+ // clang-format on
+
+ return __result;
+}
+
+template <class _Fp, class _Tp>
+_LIBCPP_HIDE_FROM_ABI __float_result __format_buffer_hexadecimal_upper_case(
+ const __float_buffer<_Fp>& __buffer, _Tp __value, int __precision, char* __integral) {
+ __float_result __result =
+ __formatter::__format_buffer_hexadecimal_lower_case(__buffer, __value, __precision, __integral);
+ std::transform(__result.__integral, __result.__exponent, __result.__integral, __hex_to_upper);
+ *__result.__exponent = 'P';
+ return __result;
+}
+
+template <class _Fp, class _Tp>
+_LIBCPP_HIDE_FROM_ABI __float_result __format_buffer_scientific_lower_case(
+ const __float_buffer<_Fp>& __buffer, _Tp __value, int __precision, char* __integral) {
+ __float_result __result;
+ __result.__integral = __integral;
+ __result.__last =
+ __formatter::__to_buffer(__integral, __buffer.end(), __value, chars_format::scientific, __precision);
+
+ char* __first = __integral + 1;
+ _LIBCPP_ASSERT_INTERNAL(__first != __result.__last, "No exponent present");
+ if (*__first == '.') {
+ __result.__radix_point = __first;
+ __result.__exponent = __formatter::__find_exponent(__first + 1, __result.__last);
+ } else {
+ __result.__radix_point = __result.__last;
+ __result.__exponent = __first;
+ }
+
+ // clang-format off
+ _LIBCPP_ASSERT_INTERNAL((__result.__integral != __result.__last) &&
+ (__result.__radix_point == __result.__last || *__result.__radix_point == '.') &&
+ (__result.__exponent != __result.__last && *__result.__exponent == 'e'),
+ "Post-condition failure.");
+ // clang-format on
+ return __result;
+}
+
+template <class _Fp, class _Tp>
+_LIBCPP_HIDE_FROM_ABI __float_result __format_buffer_scientific_upper_case(
+ const __float_buffer<_Fp>& __buffer, _Tp __value, int __precision, char* __integral) {
+ __float_result __result =
+ __formatter::__format_buffer_scientific_lower_case(__buffer, __value, __precision, __integral);
+ *__result.__exponent = 'E';
+ return __result;
+}
+
+template <class _Fp, class _Tp>
+_LIBCPP_HIDE_FROM_ABI __float_result
+__format_buffer_fixed(const __float_buffer<_Fp>& __buffer, _Tp __value, int __precision, char* __integral) {
+ __float_result __result;
+ __result.__integral = __integral;
+ __result.__last = __formatter::__to_buffer(__integral, __buffer.end(), __value, chars_format::fixed, __precision);
+
+ // When there's no precision there's no radix point.
+ // Else the radix point is placed at __precision + 1 from the end.
+ // By converting __precision to a bool the subtraction can be done
+ // unconditionally.
+ __result.__radix_point = __result.__last - (__precision + bool(__precision));
+ __result.__exponent = __result.__last;
+
+ // clang-format off
+ _LIBCPP_ASSERT_INTERNAL((__result.__integral != __result.__last) &&
+ (__result.__radix_point == __result.__last || *__result.__radix_point == '.') &&
+ (__result.__exponent == __result.__last),
+ "Post-condition failure.");
+ // clang-format on
+ return __result;
+}
+
+template <class _Fp, class _Tp>
+_LIBCPP_HIDE_FROM_ABI __float_result
+__format_buffer_general_lower_case(__float_buffer<_Fp>& __buffer, _Tp __value, int __precision, char* __integral) {
+ __buffer.__remove_trailing_zeros();
+
+ __float_result __result;
+ __result.__integral = __integral;
+ __result.__last = __formatter::__to_buffer(__integral, __buffer.end(), __value, chars_format::general, __precision);
+
+ char* __first = __integral + 1;
+ if (__first == __result.__last) {
+ __result.__radix_point = __result.__last;
+ __result.__exponent = __result.__last;
+ } else {
+ __result.__exponent = __formatter::__find_exponent(__first, __result.__last);
+ if (__result.__exponent != __result.__last)
+ // In scientific mode if there's a radix point it will always be after
+ // the first digit. (This is the position __first points at).
+ __result.__radix_point = *__first == '.' ? __first : __result.__last;
+ else {
+ // In fixed mode the algorithm truncates trailing spaces and possibly the
+ // radix point. There's no good guess for the position of the radix point
+ // therefore scan the output after the first digit.
+ __result.__radix_point = std::find(__first, __result.__last, '.');
+ }
+ }
+
+ // clang-format off
+ _LIBCPP_ASSERT_INTERNAL((__result.__integral != __result.__last) &&
+ (__result.__radix_point == __result.__last || *__result.__radix_point == '.') &&
+ (__result.__exponent == __result.__last || *__result.__exponent == 'e'),
+ "Post-condition failure.");
+ // clang-format on
+
+ return __result;
+}
+
+template <class _Fp, class _Tp>
+_LIBCPP_HIDE_FROM_ABI __float_result
+__format_buffer_general_upper_case(__float_buffer<_Fp>& __buffer, _Tp __value, int __precision, char* __integral) {
+ __float_result __result = __formatter::__format_buffer_general_lower_case(__buffer, __value, __precision, __integral);
+ if (__result.__exponent != __result.__last)
+ *__result.__exponent = 'E';
+ return __result;
+}
+
+/// Fills the buffer with the data based on the requested formatting.
+///
+/// This function, when needed, turns the characters to upper case and
+/// determines the "interesting" locations which are returned to the caller.
+///
+/// This means the caller never has to convert the contents of the buffer to
+/// upper case or search for radix points and the location of the exponent.
+/// This gives a bit of overhead. The original code didn't do that, but due
+/// to the number of possible additional work needed to turn this number to
+/// the proper output the code was littered with tests for upper cases and
+/// searches for radix points and exponents.
+/// - When a precision larger than the type's precision is selected
+/// additional zero characters need to be written before the exponent.
+/// - alternate form needs to add a radix point when not present.
+/// - localization needs to do grouping in the integral part.
+template <class _Fp, class _Tp>
+// TODO FMT _Fp should just be _Tp when to_chars has proper long double support.
+_LIBCPP_HIDE_FROM_ABI __float_result __format_buffer(
+ __float_buffer<_Fp>& __buffer,
+ _Tp __value,
+ bool __negative,
+ bool __has_precision,
+ __format_spec::__sign __sign,
+ __format_spec::__type __type) {
+ char* __first = __formatter::__insert_sign(__buffer.begin(), __negative, __sign);
+ switch (__type) {
+ case __format_spec::__type::__default:
+ if (__has_precision)
+ return __formatter::__format_buffer_general_lower_case(__buffer, __value, __buffer.__precision(), __first);
+ else
+ return __formatter::__format_buffer_default(__buffer, __value, __first);
+
+ case __format_spec::__type::__hexfloat_lower_case:
+ return __formatter::__format_buffer_hexadecimal_lower_case(
+ __buffer, __value, __has_precision ? __buffer.__precision() : -1, __first);
+
+ case __format_spec::__type::__hexfloat_upper_case:
+ return __formatter::__format_buffer_hexadecimal_upper_case(
+ __buffer, __value, __has_precision ? __buffer.__precision() : -1, __first);
+
+ case __format_spec::__type::__scientific_lower_case:
+ return __formatter::__format_buffer_scientific_lower_case(__buffer, __value, __buffer.__precision(), __first);
+
+ case __format_spec::__type::__scientific_upper_case:
+ return __formatter::__format_buffer_scientific_upper_case(__buffer, __value, __buffer.__precision(), __first);
+
+ case __format_spec::__type::__fixed_lower_case:
+ case __format_spec::__type::__fixed_upper_case:
+ return __formatter::__format_buffer_fixed(__buffer, __value, __buffer.__precision(), __first);
+
+ case __format_spec::__type::__general_lower_case:
+ return __formatter::__format_buffer_general_lower_case(__buffer, __value, __buffer.__precision(), __first);
+
+ case __format_spec::__type::__general_upper_case:
+ return __formatter::__format_buffer_general_upper_case(__buffer, __value, __buffer.__precision(), __first);
+
+ default:
+ _LIBCPP_ASSERT_INTERNAL(false, "The parser should have validated the type");
+ __libcpp_unreachable();
+ }
+}
+
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+template <class _OutIt, class _Fp, class _CharT>
+_LIBCPP_HIDE_FROM_ABI _OutIt __format_locale_specific_form(
+ _OutIt __out_it,
+ const __float_buffer<_Fp>& __buffer,
+ const __float_result& __result,
+ std::locale __loc,
+ __format_spec::__parsed_specifications<_CharT> __specs) {
+ const auto& __np = std::use_facet<numpunct<_CharT>>(__loc);
+ string __grouping = __np.grouping();
+ char* __first = __result.__integral;
+ // When no radix point or exponent are present __last will be __result.__last.
+ char* __last = std::min(__result.__radix_point, __result.__exponent);
+
+ ptrdiff_t __digits = __last - __first;
+ if (!__grouping.empty()) {
+ if (__digits <= __grouping[0])
+ __grouping.clear();
+ else
+ __grouping = __formatter::__determine_grouping(__digits, __grouping);
+ }
+
+ ptrdiff_t __size =
+ __result.__last - __buffer.begin() + // Formatted string
+ __buffer.__num_trailing_zeros() + // Not yet rendered zeros
+ __grouping.size() - // Grouping contains one
+ !__grouping.empty(); // additional character
+
+ __formatter::__padding_size_result __padding = {0, 0};
+ bool __zero_padding = __specs.__alignment_ == __format_spec::__alignment::__zero_padding;
+ if (__size < __specs.__width_) {
+ if (__zero_padding) {
+ __specs.__alignment_ = __format_spec::__alignment::__right;
+ __specs.__fill_.__data[0] = _CharT('0');
+ }
+
+ __padding = __formatter::__padding_size(__size, __specs.__width_, __specs.__alignment_);
+ }
+
+ // sign and (zero padding or alignment)
+ if (__zero_padding && __first != __buffer.begin())
+ *__out_it++ = *__buffer.begin();
+ __out_it = __formatter::__fill(std::move(__out_it), __padding.__before_, __specs.__fill_);
+ if (!__zero_padding && __first != __buffer.begin())
+ *__out_it++ = *__buffer.begin();
+
+ // integral part
+ if (__grouping.empty()) {
+ __out_it = __formatter::__copy(__first, __digits, std::move(__out_it));
+ } else {
+ auto __r = __grouping.rbegin();
+ auto __e = __grouping.rend() - 1;
+ _CharT __sep = __np.thousands_sep();
+ // The output is divided in small groups of numbers to write:
+ // - A group before the first separator.
+ // - A separator and a group, repeated for the number of separators.
+ // - A group after the last separator.
+ // This loop achieves that process by testing the termination condition
+ // midway in the loop.
+ while (true) {
+ __out_it = __formatter::__copy(__first, *__r, std::move(__out_it));
+ __first += *__r;
+
+ if (__r == __e)
+ break;
+
+ ++__r;
+ *__out_it++ = __sep;
+ }
+ }
+
+ // fractional part
+ if (__result.__radix_point != __result.__last) {
+ *__out_it++ = __np.decimal_point();
+ __out_it = __formatter::__copy(__result.__radix_point + 1, __result.__exponent, std::move(__out_it));
+ __out_it = __formatter::__fill(std::move(__out_it), __buffer.__num_trailing_zeros(), _CharT('0'));
+ }
+
+ // exponent
+ if (__result.__exponent != __result.__last)
+ __out_it = __formatter::__copy(__result.__exponent, __result.__last, std::move(__out_it));
+
+ // alignment
+ return __formatter::__fill(std::move(__out_it), __padding.__after_, __specs.__fill_);
+}
+# endif // _LIBCPP_HAS_NO_LOCALIZATION
+
+template <class _OutIt, class _CharT>
+_LIBCPP_HIDE_FROM_ABI _OutIt __format_floating_point_non_finite(
+ _OutIt __out_it, __format_spec::__parsed_specifications<_CharT> __specs, bool __negative, bool __isnan) {
+ char __buffer[4];
+ char* __last = __formatter::__insert_sign(__buffer, __negative, __specs.__std_.__sign_);
+
+ // to_chars can return inf, infinity, nan, and nan(n-char-sequence).
+ // The format library requires inf and nan.
+ // All in one expression to avoid dangling references.
+ bool __upper_case =
+ __specs.__std_.__type_ == __format_spec::__type::__hexfloat_upper_case ||
+ __specs.__std_.__type_ == __format_spec::__type::__scientific_upper_case ||
+ __specs.__std_.__type_ == __format_spec::__type::__fixed_upper_case ||
+ __specs.__std_.__type_ == __format_spec::__type::__general_upper_case;
+ __last = std::copy_n(&("infnanINFNAN"[6 * __upper_case + 3 * __isnan]), 3, __last);
+
+ // [format.string.std]/13
+ // A zero (0) character preceding the width field pads the field with
+ // leading zeros (following any indication of sign or base) to the field
+ // width, except when applied to an infinity or NaN.
+ if (__specs.__alignment_ == __format_spec::__alignment::__zero_padding)
+ __specs.__alignment_ = __format_spec::__alignment::__right;
+
+ return __formatter::__write(__buffer, __last, std::move(__out_it), __specs);
+}
+
+/// Writes additional zero's for the precision before the exponent.
+/// This is used when the precision requested in the format string is larger
+/// than the maximum precision of the floating-point type. These precision
+/// digits are always 0.
+///
+/// \param __exponent The location of the exponent character.
+/// \param __num_trailing_zeros The number of 0's to write before the exponent
+/// character.
+template <class _CharT, class _ParserCharT>
+_LIBCPP_HIDE_FROM_ABI auto __write_using_trailing_zeros(
+ const _CharT* __first,
+ const _CharT* __last,
+ output_iterator<const _CharT&> auto __out_it,
+ __format_spec::__parsed_specifications<_ParserCharT> __specs,
+ size_t __size,
+ const _CharT* __exponent,
+ size_t __num_trailing_zeros) -> decltype(__out_it) {
+ _LIBCPP_ASSERT_INTERNAL(__first <= __last, "Not a valid range");
+ _LIBCPP_ASSERT_INTERNAL(__num_trailing_zeros > 0, "The overload not writing trailing zeros should have been used");
+
+ __padding_size_result __padding =
+ __formatter::__padding_size(__size + __num_trailing_zeros, __specs.__width_, __specs.__alignment_);
+ __out_it = __formatter::__fill(std::move(__out_it), __padding.__before_, __specs.__fill_);
+ __out_it = __formatter::__copy(__first, __exponent, std::move(__out_it));
+ __out_it = __formatter::__fill(std::move(__out_it), __num_trailing_zeros, _CharT('0'));
+ __out_it = __formatter::__copy(__exponent, __last, std::move(__out_it));
+ return __formatter::__fill(std::move(__out_it), __padding.__after_, __specs.__fill_);
+}
+
+template <floating_point _Tp, class _CharT, class _FormatContext>
+_LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+__format_floating_point(_Tp __value, _FormatContext& __ctx, __format_spec::__parsed_specifications<_CharT> __specs) {
+ bool __negative = std::signbit(__value);
+
+ if (!std::isfinite(__value)) [[unlikely]]
+ return __formatter::__format_floating_point_non_finite(__ctx.out(), __specs, __negative, std::isnan(__value));
+
+ // Depending on the std-format-spec string the sign and the value
+ // might not be outputted together:
+ // - zero-padding may insert additional '0' characters.
+ // Therefore the value is processed as a non negative value.
+ // The function @ref __insert_sign will insert a '-' when the value was
+ // negative.
+
+ if (__negative)
+ __value = -__value;
+
+ // TODO FMT _Fp should just be _Tp when to_chars has proper long double support.
+ using _Fp = conditional_t<same_as<_Tp, long double>, double, _Tp>;
+ // Force the type of the precision to avoid -1 to become an unsigned value.
+ __float_buffer<_Fp> __buffer(__specs.__precision_);
+ __float_result __result = __formatter::__format_buffer(
+ __buffer, __value, __negative, (__specs.__has_precision()), __specs.__std_.__sign_, __specs.__std_.__type_);
+
+ if (__specs.__std_.__alternate_form_) {
+ if (__result.__radix_point == __result.__last) {
+ *__result.__last++ = '.';
+
+ // When there is an exponent the point needs to be moved before the
+ // exponent. When there's no exponent the rotate does nothing. Since
+ // rotate tests whether the operation is a nop, call it unconditionally.
+ std::rotate(__result.__exponent, __result.__last - 1, __result.__last);
+ __result.__radix_point = __result.__exponent;
+
+ // The radix point is always placed before the exponent.
+ // - No exponent needs to point to the new last.
+ // - An exponent needs to move one position to the right.
+ // So it's safe to increment the value unconditionally.
+ ++__result.__exponent;
+ }
+
+ // [format.string.std]/6
+ // In addition, for g and G conversions, trailing zeros are not removed
+ // from the result.
+ //
+ // If the type option for a floating-point type is none it may use the
+ // general formatting, but it's not a g or G conversion. So in that case
+ // the formatting should not append trailing zeros.
+ bool __is_general = __specs.__std_.__type_ == __format_spec::__type::__general_lower_case ||
+ __specs.__std_.__type_ == __format_spec::__type::__general_upper_case;
+
+ if (__is_general) {
+ // https://en.cppreference.com/w/c/io/fprintf
+ // Let P equal the precision if nonzero, 6 if the precision is not
+ // specified, or 1 if the precision is 0. Then, if a conversion with
+ // style E would have an exponent of X:
+ int __p = std::max<int>(1, (__specs.__has_precision() ? __specs.__precision_ : 6));
+ if (__result.__exponent == __result.__last)
+ // if P > X >= -4, the conversion is with style f or F and precision P - 1 - X.
+ // By including the radix point it calculates P - (1 + X)
+ __p -= __result.__radix_point - __result.__integral;
+ else
+ // otherwise, the conversion is with style e or E and precision P - 1.
+ --__p;
+
+ ptrdiff_t __precision = (__result.__exponent - __result.__radix_point) - 1;
+ if (__precision < __p)
+ __buffer.__add_trailing_zeros(__p - __precision);
+ }
+ }
+
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+ if (__specs.__std_.__locale_specific_form_)
+ return __formatter::__format_locale_specific_form(__ctx.out(), __buffer, __result, __ctx.locale(), __specs);
+# endif
+
+ ptrdiff_t __size = __result.__last - __buffer.begin();
+ int __num_trailing_zeros = __buffer.__num_trailing_zeros();
+ if (__size + __num_trailing_zeros >= __specs.__width_) {
+ if (__num_trailing_zeros && __result.__exponent != __result.__last)
+ // Insert trailing zeros before exponent character.
+ return __formatter::__copy(
+ __result.__exponent,
+ __result.__last,
+ __formatter::__fill(__formatter::__copy(__buffer.begin(), __result.__exponent, __ctx.out()),
+ __num_trailing_zeros,
+ _CharT('0')));
+
+ return __formatter::__fill(
+ __formatter::__copy(__buffer.begin(), __result.__last, __ctx.out()), __num_trailing_zeros, _CharT('0'));
+ }
+
+ auto __out_it = __ctx.out();
+ char* __first = __buffer.begin();
+ if (__specs.__alignment_ == __format_spec::__alignment ::__zero_padding) {
+ // When there is a sign output it before the padding. Note the __size
+ // doesn't need any adjustment, regardless whether the sign is written
+ // here or in __formatter::__write.
+ if (__first != __result.__integral)
+ *__out_it++ = *__first++;
+ // After the sign is written, zero padding is the same a right alignment
+ // with '0'.
+ __specs.__alignment_ = __format_spec::__alignment::__right;
+ __specs.__fill_.__data[0] = _CharT('0');
+ }
+
+ if (__num_trailing_zeros)
+ return __formatter::__write_using_trailing_zeros(
+ __first, __result.__last, std::move(__out_it), __specs, __size, __result.__exponent, __num_trailing_zeros);
+
+ return __formatter::__write(__first, __result.__last, std::move(__out_it), __specs, __size);
+}
+
+} // namespace __formatter
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS __formatter_floating_point {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_floating_point);
+ __format_spec::__process_parsed_floating_point(__parser_, "a floating-point");
+ return __result;
+ }
+
+ template <floating_point _Tp, class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(_Tp __value, _FormatContext& __ctx) const {
+ return __formatter::__format_floating_point(__value, __ctx, __parser_.__get_parsed_std_specifications(__ctx));
+ }
+
+ __format_spec::__parser<_CharT> __parser_;
+};
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<float, _CharT> : public __formatter_floating_point<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<double, _CharT> : public __formatter_floating_point<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<long double, _CharT> : public __formatter_floating_point<_CharT> {};
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_FORMATTER_FLOATING_POINT_H
diff --git a/libcxx/include/__cxx03/__format/formatter_integer.h b/libcxx/include/__cxx03/__format/formatter_integer.h
new file mode 100644
index 00000000000000..41400f00478eb4
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_integer.h
@@ -0,0 +1,95 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_INTEGER_H
+#define _LIBCPP___FORMAT_FORMATTER_INTEGER_H
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/formatter_integral.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/make_32_64_or_128_bit.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS __formatter_integer {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_integral);
+ __format_spec::__process_parsed_integer(__parser_, "an integer");
+ return __result;
+ }
+
+ template <integral _Tp, class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(_Tp __value, _FormatContext& __ctx) const {
+ __format_spec::__parsed_specifications<_CharT> __specs = __parser_.__get_parsed_std_specifications(__ctx);
+
+ if (__specs.__std_.__type_ == __format_spec::__type::__char)
+ return __formatter::__format_char(__value, __ctx.out(), __specs);
+
+ using _Type = __make_32_64_or_128_bit_t<_Tp>;
+ static_assert(!is_void<_Type>::value, "unsupported integral type used in __formatter_integer::__format");
+
+ // Reduce the number of instantiation of the integer formatter
+ return __formatter::__format_integer(static_cast<_Type>(__value), __ctx, __specs);
+ }
+
+ __format_spec::__parser<_CharT> __parser_;
+};
+
+// Signed integral types.
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<signed char, _CharT> : public __formatter_integer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<short, _CharT> : public __formatter_integer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<int, _CharT> : public __formatter_integer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<long, _CharT> : public __formatter_integer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<long long, _CharT> : public __formatter_integer<_CharT> {};
+# ifndef _LIBCPP_HAS_NO_INT128
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<__int128_t, _CharT> : public __formatter_integer<_CharT> {};
+# endif
+
+// Unsigned integral types.
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<unsigned char, _CharT> : public __formatter_integer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<unsigned short, _CharT> : public __formatter_integer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<unsigned, _CharT> : public __formatter_integer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<unsigned long, _CharT> : public __formatter_integer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<unsigned long long, _CharT> : public __formatter_integer<_CharT> {};
+# ifndef _LIBCPP_HAS_NO_INT128
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<__uint128_t, _CharT> : public __formatter_integer<_CharT> {};
+# endif
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMATTER_INTEGER_H
diff --git a/libcxx/include/__cxx03/__format/formatter_integral.h b/libcxx/include/__cxx03/__format/formatter_integral.h
new file mode 100644
index 00000000000000..eca966f8886f84
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_integral.h
@@ -0,0 +1,445 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_INTEGRAL_H
+#define _LIBCPP___FORMAT_FORMATTER_INTEGRAL_H
+
+#include <__charconv/to_chars_integral.h>
+#include <__charconv/to_chars_result.h>
+#include <__charconv/traits.h>
+#include <__concepts/arithmetic.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_error.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__system_error/errc.h>
+#include <__type_traits/make_unsigned.h>
+#include <__utility/unreachable.h>
+#include <array>
+#include <limits>
+#include <string>
+#include <string_view>
+
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+# include <__locale>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __formatter {
+
+//
+// Generic
+//
+
+template <contiguous_iterator _Iterator>
+ requires same_as<char, iter_value_t<_Iterator>>
+_LIBCPP_HIDE_FROM_ABI inline _Iterator __insert_sign(_Iterator __buf, bool __negative, __format_spec::__sign __sign) {
+ if (__negative)
+ *__buf++ = '-';
+ else
+ switch (__sign) {
+ case __format_spec::__sign::__default:
+ case __format_spec::__sign::__minus:
+ // No sign added.
+ break;
+ case __format_spec::__sign::__plus:
+ *__buf++ = '+';
+ break;
+ case __format_spec::__sign::__space:
+ *__buf++ = ' ';
+ break;
+ }
+
+ return __buf;
+}
+
+/**
+ * Determines the required grouping based on the size of the input.
+ *
+ * The grouping's last element will be repeated. For simplicity this repeating
+ * is unwrapped based on the length of the input. (When the input is short some
+ * groups are not processed.)
+ *
+ * @returns The size of the groups to write. This means the number of
+ * separator characters written is size() - 1.
+ *
+ * @note Since zero-sized groups cause issues they are silently ignored.
+ *
+ * @note The grouping field of the locale is always a @c std::string,
+ * regardless whether the @c std::numpunct's type is @c char or @c wchar_t.
+ */
+_LIBCPP_HIDE_FROM_ABI inline string __determine_grouping(ptrdiff_t __size, const string& __grouping) {
+ _LIBCPP_ASSERT_INTERNAL(!__grouping.empty() && __size > __grouping[0],
+ "The slow grouping formatting is used while there will be no separators written");
+ string __r;
+ auto __end = __grouping.end() - 1;
+ auto __ptr = __grouping.begin();
+
+ while (true) {
+ __size -= *__ptr;
+ if (__size > 0)
+ __r.push_back(*__ptr);
+ else {
+ // __size <= 0 so the value pushed will be <= *__ptr.
+ __r.push_back(*__ptr + __size);
+ return __r;
+ }
+
+ // Proceed to the next group.
+ if (__ptr != __end) {
+ do {
+ ++__ptr;
+ // Skip grouping with a width of 0.
+ } while (*__ptr == 0 && __ptr != __end);
+ }
+ }
+
+ __libcpp_unreachable();
+}
+
+//
+// Char
+//
+
+template <__fmt_char_type _CharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__format_char(integral auto __value,
+ output_iterator<const _CharT&> auto __out_it,
+ __format_spec::__parsed_specifications<_CharT> __specs) -> decltype(__out_it) {
+ using _Tp = decltype(__value);
+ if constexpr (!same_as<_CharT, _Tp>) {
+ // cmp_less and cmp_greater can't be used for character types.
+ if constexpr (signed_integral<_CharT> == signed_integral<_Tp>) {
+ if (__value < numeric_limits<_CharT>::min() || __value > numeric_limits<_CharT>::max())
+ std::__throw_format_error("Integral value outside the range of the char type");
+ } else if constexpr (signed_integral<_CharT>) {
+ // _CharT is signed _Tp is unsigned
+ if (__value > static_cast<make_unsigned_t<_CharT>>(numeric_limits<_CharT>::max()))
+ std::__throw_format_error("Integral value outside the range of the char type");
+ } else {
+ // _CharT is unsigned _Tp is signed
+ if (__value < 0 || static_cast<make_unsigned_t<_Tp>>(__value) > numeric_limits<_CharT>::max())
+ std::__throw_format_error("Integral value outside the range of the char type");
+ }
+ }
+
+ const auto __c = static_cast<_CharT>(__value);
+ return __formatter::__write(std::addressof(__c), std::addressof(__c) + 1, std::move(__out_it), __specs);
+}
+
+//
+// Integer
+//
+
+/** Wrapper around @ref to_chars, returning the output iterator. */
+template <contiguous_iterator _Iterator, integral _Tp>
+ requires same_as<char, iter_value_t<_Iterator>>
+_LIBCPP_HIDE_FROM_ABI _Iterator __to_buffer(_Iterator __first, _Iterator __last, _Tp __value, int __base) {
+ // TODO FMT Evaluate code overhead due to not calling the internal function
+ // directly. (Should be zero overhead.)
+ to_chars_result __r = std::to_chars(std::to_address(__first), std::to_address(__last), __value, __base);
+ _LIBCPP_ASSERT_INTERNAL(__r.ec == errc(0), "Internal buffer too small");
+ auto __diff = __r.ptr - std::to_address(__first);
+ return __first + __diff;
+}
+
+/**
+ * Helper to determine the buffer size to output a integer in Base @em x.
+ *
+ * There are several overloads for the supported bases. The function uses the
+ * base as template argument so it can be used in a constant expression.
+ */
+template <unsigned_integral _Tp, size_t _Base>
+consteval size_t __buffer_size() noexcept
+ requires(_Base == 2)
+{
+ return numeric_limits<_Tp>::digits // The number of binary digits.
+ + 2 // Reserve space for the '0[Bb]' prefix.
+ + 1; // Reserve space for the sign.
+}
+
+template <unsigned_integral _Tp, size_t _Base>
+consteval size_t __buffer_size() noexcept
+ requires(_Base == 8)
+{
+ return numeric_limits<_Tp>::digits // The number of binary digits.
+ / 3 // Adjust to octal.
+ + 1 // Turn floor to ceil.
+ + 1 // Reserve space for the '0' prefix.
+ + 1; // Reserve space for the sign.
+}
+
+template <unsigned_integral _Tp, size_t _Base>
+consteval size_t __buffer_size() noexcept
+ requires(_Base == 10)
+{
+ return numeric_limits<_Tp>::digits10 // The floored value.
+ + 1 // Turn floor to ceil.
+ + 1; // Reserve space for the sign.
+}
+
+template <unsigned_integral _Tp, size_t _Base>
+consteval size_t __buffer_size() noexcept
+ requires(_Base == 16)
+{
+ return numeric_limits<_Tp>::digits // The number of binary digits.
+ / 4 // Adjust to hexadecimal.
+ + 2 // Reserve space for the '0[Xx]' prefix.
+ + 1; // Reserve space for the sign.
+}
+
+template <class _OutIt, contiguous_iterator _Iterator, class _CharT>
+ requires same_as<char, iter_value_t<_Iterator>>
+_LIBCPP_HIDE_FROM_ABI _OutIt __write_using_decimal_separators(
+ _OutIt __out_it,
+ _Iterator __begin,
+ _Iterator __first,
+ _Iterator __last,
+ string&& __grouping,
+ _CharT __sep,
+ __format_spec::__parsed_specifications<_CharT> __specs) {
+ int __size = (__first - __begin) + // [sign][prefix]
+ (__last - __first) + // data
+ (__grouping.size() - 1); // number of separator characters
+
+ __padding_size_result __padding = {0, 0};
+ if (__specs.__alignment_ == __format_spec::__alignment::__zero_padding) {
+ // Write [sign][prefix].
+ __out_it = __formatter::__copy(__begin, __first, std::move(__out_it));
+
+ if (__specs.__width_ > __size) {
+ // Write zero padding.
+ __padding.__before_ = __specs.__width_ - __size;
+ __out_it = __formatter::__fill(std::move(__out_it), __specs.__width_ - __size, _CharT('0'));
+ }
+ } else {
+ if (__specs.__width_ > __size) {
+ // Determine padding and write padding.
+ __padding = __formatter::__padding_size(__size, __specs.__width_, __specs.__alignment_);
+
+ __out_it = __formatter::__fill(std::move(__out_it), __padding.__before_, __specs.__fill_);
+ }
+ // Write [sign][prefix].
+ __out_it = __formatter::__copy(__begin, __first, std::move(__out_it));
+ }
+
+ auto __r = __grouping.rbegin();
+ auto __e = __grouping.rend() - 1;
+ _LIBCPP_ASSERT_INTERNAL(
+ __r != __e, "The slow grouping formatting is used while there will be no separators written.");
+ // The output is divided in small groups of numbers to write:
+ // - A group before the first separator.
+ // - A separator and a group, repeated for the number of separators.
+ // - A group after the last separator.
+ // This loop achieves that process by testing the termination condition
+ // midway in the loop.
+ //
+ // TODO FMT This loop evaluates the loop invariant `__parser.__type !=
+ // _Flags::_Type::__hexadecimal_upper_case` for every iteration. (This test
+ // happens in the __write call.) Benchmark whether making two loops and
+ // hoisting the invariant is worth the effort.
+ while (true) {
+ if (__specs.__std_.__type_ == __format_spec::__type::__hexadecimal_upper_case) {
+ __last = __first + *__r;
+ __out_it = __formatter::__transform(__first, __last, std::move(__out_it), __hex_to_upper);
+ __first = __last;
+ } else {
+ __out_it = __formatter::__copy(__first, *__r, std::move(__out_it));
+ __first += *__r;
+ }
+
+ if (__r == __e)
+ break;
+
+ ++__r;
+ *__out_it++ = __sep;
+ }
+
+ return __formatter::__fill(std::move(__out_it), __padding.__after_, __specs.__fill_);
+}
+
+template <unsigned_integral _Tp, contiguous_iterator _Iterator, class _CharT, class _FormatContext>
+ requires same_as<char, iter_value_t<_Iterator>>
+_LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator __format_integer(
+ _Tp __value,
+ _FormatContext& __ctx,
+ __format_spec::__parsed_specifications<_CharT> __specs,
+ bool __negative,
+ _Iterator __begin,
+ _Iterator __end,
+ const char* __prefix,
+ int __base) {
+ _Iterator __first = __formatter::__insert_sign(__begin, __negative, __specs.__std_.__sign_);
+ if (__specs.__std_.__alternate_form_ && __prefix)
+ while (*__prefix)
+ *__first++ = *__prefix++;
+
+ _Iterator __last = __formatter::__to_buffer(__first, __end, __value, __base);
+
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+ if (__specs.__std_.__locale_specific_form_) {
+ const auto& __np = std::use_facet<numpunct<_CharT>>(__ctx.locale());
+ string __grouping = __np.grouping();
+ ptrdiff_t __size = __last - __first;
+ // Writing the grouped form has more overhead than the normal output
+ // routines. If there will be no separators written the locale-specific
+ // form is identical to the normal routine. Test whether to grouped form
+ // is required.
+ if (!__grouping.empty() && __size > __grouping[0])
+ return __formatter::__write_using_decimal_separators(
+ __ctx.out(),
+ __begin,
+ __first,
+ __last,
+ __formatter::__determine_grouping(__size, __grouping),
+ __np.thousands_sep(),
+ __specs);
+ }
+# endif
+ auto __out_it = __ctx.out();
+ if (__specs.__alignment_ != __format_spec::__alignment::__zero_padding)
+ __first = __begin;
+ else {
+ // __buf contains [sign][prefix]data
+ // ^ location of __first
+ // The zero padding is done like:
+ // - Write [sign][prefix]
+ // - Write data right aligned with '0' as fill character.
+ __out_it = __formatter::__copy(__begin, __first, std::move(__out_it));
+ __specs.__alignment_ = __format_spec::__alignment::__right;
+ __specs.__fill_.__data[0] = _CharT('0');
+ int32_t __size = __first - __begin;
+
+ __specs.__width_ -= std::min(__size, __specs.__width_);
+ }
+
+ if (__specs.__std_.__type_ != __format_spec::__type::__hexadecimal_upper_case) [[likely]]
+ return __formatter::__write(__first, __last, __ctx.out(), __specs);
+
+ return __formatter::__write_transformed(__first, __last, __ctx.out(), __specs, __formatter::__hex_to_upper);
+}
+
+template <unsigned_integral _Tp, class _CharT, class _FormatContext>
+_LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+__format_integer(_Tp __value,
+ _FormatContext& __ctx,
+ __format_spec::__parsed_specifications<_CharT> __specs,
+ bool __negative = false) {
+ switch (__specs.__std_.__type_) {
+ case __format_spec::__type::__binary_lower_case: {
+ array<char, __formatter::__buffer_size<decltype(__value), 2>()> __array;
+ return __formatter::__format_integer(__value, __ctx, __specs, __negative, __array.begin(), __array.end(), "0b", 2);
+ }
+ case __format_spec::__type::__binary_upper_case: {
+ array<char, __formatter::__buffer_size<decltype(__value), 2>()> __array;
+ return __formatter::__format_integer(__value, __ctx, __specs, __negative, __array.begin(), __array.end(), "0B", 2);
+ }
+ case __format_spec::__type::__octal: {
+ // Octal is special; if __value == 0 there's no prefix.
+ array<char, __formatter::__buffer_size<decltype(__value), 8>()> __array;
+ return __formatter::__format_integer(
+ __value, __ctx, __specs, __negative, __array.begin(), __array.end(), __value != 0 ? "0" : nullptr, 8);
+ }
+ case __format_spec::__type::__default:
+ case __format_spec::__type::__decimal: {
+ array<char, __formatter::__buffer_size<decltype(__value), 10>()> __array;
+ return __formatter::__format_integer(
+ __value, __ctx, __specs, __negative, __array.begin(), __array.end(), nullptr, 10);
+ }
+ case __format_spec::__type::__hexadecimal_lower_case: {
+ array<char, __formatter::__buffer_size<decltype(__value), 16>()> __array;
+ return __formatter::__format_integer(__value, __ctx, __specs, __negative, __array.begin(), __array.end(), "0x", 16);
+ }
+ case __format_spec::__type::__hexadecimal_upper_case: {
+ array<char, __formatter::__buffer_size<decltype(__value), 16>()> __array;
+ return __formatter::__format_integer(__value, __ctx, __specs, __negative, __array.begin(), __array.end(), "0X", 16);
+ }
+ default:
+ _LIBCPP_ASSERT_INTERNAL(false, "The parse function should have validated the type");
+ __libcpp_unreachable();
+ }
+}
+
+template <signed_integral _Tp, class _CharT, class _FormatContext>
+_LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+__format_integer(_Tp __value, _FormatContext& __ctx, __format_spec::__parsed_specifications<_CharT> __specs) {
+ // Depending on the std-format-spec string the sign and the value
+ // might not be outputted together:
+ // - alternate form may insert a prefix string.
+ // - zero-padding may insert additional '0' characters.
+ // Therefore the value is processed as a positive unsigned value.
+ // The function @ref __insert_sign will a '-' when the value was negative.
+ auto __r = std::__to_unsigned_like(__value);
+ bool __negative = __value < 0;
+ if (__negative)
+ __r = std::__complement(__r);
+
+ return __formatter::__format_integer(__r, __ctx, __specs, __negative);
+}
+
+//
+// Formatter arithmetic (bool)
+//
+
+template <class _CharT>
+struct _LIBCPP_TEMPLATE_VIS __bool_strings;
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS __bool_strings<char> {
+ static constexpr string_view __true{"true"};
+ static constexpr string_view __false{"false"};
+};
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+struct _LIBCPP_TEMPLATE_VIS __bool_strings<wchar_t> {
+ static constexpr wstring_view __true{L"true"};
+ static constexpr wstring_view __false{L"false"};
+};
+# endif
+
+template <class _CharT, class _FormatContext>
+_LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+__format_bool(bool __value, _FormatContext& __ctx, __format_spec::__parsed_specifications<_CharT> __specs) {
+# ifndef _LIBCPP_HAS_NO_LOCALIZATION
+ if (__specs.__std_.__locale_specific_form_) {
+ const auto& __np = std::use_facet<numpunct<_CharT>>(__ctx.locale());
+ basic_string<_CharT> __str = __value ? __np.truename() : __np.falsename();
+ return __formatter::__write_string_no_precision(basic_string_view<_CharT>{__str}, __ctx.out(), __specs);
+ }
+# endif
+ basic_string_view<_CharT> __str =
+ __value ? __formatter::__bool_strings<_CharT>::__true : __formatter::__bool_strings<_CharT>::__false;
+ return __formatter::__write(__str.begin(), __str.end(), __ctx.out(), __specs);
+}
+
+} // namespace __formatter
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_FORMATTER_INTEGRAL_H
diff --git a/libcxx/include/__cxx03/__format/formatter_output.h b/libcxx/include/__cxx03/__format/formatter_output.h
new file mode 100644
index 00000000000000..1498f64c4aeff7
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_output.h
@@ -0,0 +1,335 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_OUTPUT_H
+#define _LIBCPP___FORMAT_FORMATTER_OUTPUT_H
+
+#include <__algorithm/ranges_copy.h>
+#include <__algorithm/ranges_fill_n.h>
+#include <__algorithm/ranges_transform.h>
+#include <__bit/countl.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/buffer.h>
+#include <__format/concepts.h>
+#include <__format/formatter.h>
+#include <__format/parser_std_format_spec.h>
+#include <__format/unicode.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__memory/pointer_traits.h>
+#include <__utility/move.h>
+#include <__utility/unreachable.h>
+#include <cstddef>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __formatter {
+
+_LIBCPP_HIDE_FROM_ABI constexpr char __hex_to_upper(char __c) {
+ switch (__c) {
+ case 'a':
+ return 'A';
+ case 'b':
+ return 'B';
+ case 'c':
+ return 'C';
+ case 'd':
+ return 'D';
+ case 'e':
+ return 'E';
+ case 'f':
+ return 'F';
+ }
+ return __c;
+}
+
+struct _LIBCPP_EXPORTED_FROM_ABI __padding_size_result {
+ size_t __before_;
+ size_t __after_;
+};
+
+_LIBCPP_HIDE_FROM_ABI constexpr __padding_size_result
+__padding_size(size_t __size, size_t __width, __format_spec::__alignment __align) {
+ _LIBCPP_ASSERT_INTERNAL(__width > __size, "don't call this function when no padding is required");
+ _LIBCPP_ASSERT_INTERNAL(
+ __align != __format_spec::__alignment::__zero_padding, "the caller should have handled the zero-padding");
+
+ size_t __fill = __width - __size;
+ switch (__align) {
+ case __format_spec::__alignment::__zero_padding:
+ __libcpp_unreachable();
+
+ case __format_spec::__alignment::__left:
+ return {0, __fill};
+
+ case __format_spec::__alignment::__center: {
+ // The extra padding is divided per [format.string.std]/3
+ // __before = floor(__fill, 2);
+ // __after = ceil(__fill, 2);
+ size_t __before = __fill / 2;
+ size_t __after = __fill - __before;
+ return {__before, __after};
+ }
+ case __format_spec::__alignment::__default:
+ case __format_spec::__alignment::__right:
+ return {__fill, 0};
+ }
+ __libcpp_unreachable();
+}
+
+/// Copy wrapper.
+///
+/// This uses a "mass output function" of __format::__output_buffer when possible.
+template <__fmt_char_type _CharT, __fmt_char_type _OutCharT = _CharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__copy(basic_string_view<_CharT> __str, output_iterator<const _OutCharT&> auto __out_it) -> decltype(__out_it) {
+ if constexpr (std::same_as<decltype(__out_it), std::back_insert_iterator<__format::__output_buffer<_OutCharT>>>) {
+ __out_it.__get_container()->__copy(__str);
+ return __out_it;
+ } else if constexpr (std::same_as<decltype(__out_it), typename __format::__retarget_buffer<_OutCharT>::__iterator>) {
+ __out_it.__buffer_->__copy(__str);
+ return __out_it;
+ } else {
+ return std::ranges::copy(__str, std::move(__out_it)).out;
+ }
+}
+
+template <contiguous_iterator _Iterator,
+ __fmt_char_type _CharT = typename iterator_traits<_Iterator>::value_type,
+ __fmt_char_type _OutCharT = _CharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__copy(_Iterator __first, _Iterator __last, output_iterator<const _OutCharT&> auto __out_it) -> decltype(__out_it) {
+ return __formatter::__copy(basic_string_view{__first, __last}, std::move(__out_it));
+}
+
+template <contiguous_iterator _Iterator,
+ __fmt_char_type _CharT = typename iterator_traits<_Iterator>::value_type,
+ __fmt_char_type _OutCharT = _CharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__copy(_Iterator __first, size_t __n, output_iterator<const _OutCharT&> auto __out_it) -> decltype(__out_it) {
+ return __formatter::__copy(basic_string_view{std::to_address(__first), __n}, std::move(__out_it));
+}
+
+/// Transform wrapper.
+///
+/// This uses a "mass output function" of __format::__output_buffer when possible.
+template <contiguous_iterator _Iterator,
+ __fmt_char_type _CharT = typename iterator_traits<_Iterator>::value_type,
+ __fmt_char_type _OutCharT = _CharT,
+ class _UnaryOperation>
+_LIBCPP_HIDE_FROM_ABI auto
+__transform(_Iterator __first,
+ _Iterator __last,
+ output_iterator<const _OutCharT&> auto __out_it,
+ _UnaryOperation __operation) -> decltype(__out_it) {
+ if constexpr (std::same_as<decltype(__out_it), std::back_insert_iterator<__format::__output_buffer<_OutCharT>>>) {
+ __out_it.__get_container()->__transform(__first, __last, std::move(__operation));
+ return __out_it;
+ } else if constexpr (std::same_as<decltype(__out_it), typename __format::__retarget_buffer<_OutCharT>::__iterator>) {
+ __out_it.__buffer_->__transform(__first, __last, std::move(__operation));
+ return __out_it;
+ } else {
+ return std::ranges::transform(__first, __last, std::move(__out_it), __operation).out;
+ }
+}
+
+/// Fill wrapper.
+///
+/// This uses a "mass output function" of __format::__output_buffer when possible.
+template <__fmt_char_type _CharT, output_iterator<const _CharT&> _OutIt>
+_LIBCPP_HIDE_FROM_ABI _OutIt __fill(_OutIt __out_it, size_t __n, _CharT __value) {
+ if constexpr (std::same_as<decltype(__out_it), std::back_insert_iterator<__format::__output_buffer<_CharT>>>) {
+ __out_it.__get_container()->__fill(__n, __value);
+ return __out_it;
+ } else if constexpr (std::same_as<decltype(__out_it), typename __format::__retarget_buffer<_CharT>::__iterator>) {
+ __out_it.__buffer_->__fill(__n, __value);
+ return __out_it;
+ } else {
+ return std::ranges::fill_n(std::move(__out_it), __n, __value);
+ }
+}
+
+# ifndef _LIBCPP_HAS_NO_UNICODE
+template <__fmt_char_type _CharT, output_iterator<const _CharT&> _OutIt>
+ requires(same_as<_CharT, char>)
+_LIBCPP_HIDE_FROM_ABI _OutIt __fill(_OutIt __out_it, size_t __n, __format_spec::__code_point<_CharT> __value) {
+ std::size_t __bytes = std::countl_one(static_cast<unsigned char>(__value.__data[0]));
+ if (__bytes == 0)
+ return __formatter::__fill(std::move(__out_it), __n, __value.__data[0]);
+
+ for (size_t __i = 0; __i < __n; ++__i)
+ __out_it = __formatter::__copy(
+ std::addressof(__value.__data[0]), std::addressof(__value.__data[0]) + __bytes, std::move(__out_it));
+ return __out_it;
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <__fmt_char_type _CharT, output_iterator<const _CharT&> _OutIt>
+ requires(same_as<_CharT, wchar_t> && sizeof(wchar_t) == 2)
+_LIBCPP_HIDE_FROM_ABI _OutIt __fill(_OutIt __out_it, size_t __n, __format_spec::__code_point<_CharT> __value) {
+ if (!__unicode::__is_high_surrogate(__value.__data[0]))
+ return __formatter::__fill(std::move(__out_it), __n, __value.__data[0]);
+
+ for (size_t __i = 0; __i < __n; ++__i)
+ __out_it = __formatter::__copy(
+ std::addressof(__value.__data[0]), std::addressof(__value.__data[0]) + 2, std::move(__out_it));
+ return __out_it;
+}
+
+template <__fmt_char_type _CharT, output_iterator<const _CharT&> _OutIt>
+ requires(same_as<_CharT, wchar_t> && sizeof(wchar_t) == 4)
+_LIBCPP_HIDE_FROM_ABI _OutIt __fill(_OutIt __out_it, size_t __n, __format_spec::__code_point<_CharT> __value) {
+ return __formatter::__fill(std::move(__out_it), __n, __value.__data[0]);
+}
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+# else // _LIBCPP_HAS_NO_UNICODE
+template <__fmt_char_type _CharT, output_iterator<const _CharT&> _OutIt>
+_LIBCPP_HIDE_FROM_ABI _OutIt __fill(_OutIt __out_it, size_t __n, __format_spec::__code_point<_CharT> __value) {
+ return __formatter::__fill(std::move(__out_it), __n, __value.__data[0]);
+}
+# endif // _LIBCPP_HAS_NO_UNICODE
+
+/// Writes the input to the output with the required padding.
+///
+/// Since the output column width is specified the function can be used for
+/// ASCII and Unicode output.
+///
+/// \pre \a __size <= \a __width. Using this function when this pre-condition
+/// doesn't hold incurs an unwanted overhead.
+///
+/// \param __str The string to write.
+/// \param __out_it The output iterator to write to.
+/// \param __specs The parsed formatting specifications.
+/// \param __size The (estimated) output column width. When the elements
+/// to be written are ASCII the following condition holds
+/// \a __size == \a __last - \a __first.
+///
+/// \returns An iterator pointing beyond the last element written.
+///
+/// \note The type of the elements in range [\a __first, \a __last) can differ
+/// from the type of \a __specs. Integer output uses \c std::to_chars for its
+/// conversion, which means the [\a __first, \a __last) always contains elements
+/// of the type \c char.
+template <class _CharT, class _ParserCharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__write(basic_string_view<_CharT> __str,
+ output_iterator<const _CharT&> auto __out_it,
+ __format_spec::__parsed_specifications<_ParserCharT> __specs,
+ ptrdiff_t __size) -> decltype(__out_it) {
+ if (__size >= __specs.__width_)
+ return __formatter::__copy(__str, std::move(__out_it));
+
+ __padding_size_result __padding = __formatter::__padding_size(__size, __specs.__width_, __specs.__std_.__alignment_);
+ __out_it = __formatter::__fill(std::move(__out_it), __padding.__before_, __specs.__fill_);
+ __out_it = __formatter::__copy(__str, std::move(__out_it));
+ return __formatter::__fill(std::move(__out_it), __padding.__after_, __specs.__fill_);
+}
+
+template <contiguous_iterator _Iterator, class _ParserCharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__write(_Iterator __first,
+ _Iterator __last,
+ output_iterator<const iter_value_t<_Iterator>&> auto __out_it,
+ __format_spec::__parsed_specifications<_ParserCharT> __specs,
+ ptrdiff_t __size) -> decltype(__out_it) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__first <= __last, "Not a valid range");
+ return __formatter::__write(basic_string_view{__first, __last}, std::move(__out_it), __specs, __size);
+}
+
+/// \overload
+///
+/// Calls the function above where \a __size = \a __last - \a __first.
+template <contiguous_iterator _Iterator, class _ParserCharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__write(_Iterator __first,
+ _Iterator __last,
+ output_iterator<const iter_value_t<_Iterator>&> auto __out_it,
+ __format_spec::__parsed_specifications<_ParserCharT> __specs) -> decltype(__out_it) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__first <= __last, "Not a valid range");
+ return __formatter::__write(__first, __last, std::move(__out_it), __specs, __last - __first);
+}
+
+template <contiguous_iterator _Iterator,
+ class _CharT = typename iterator_traits<_Iterator>::value_type,
+ class _ParserCharT,
+ class _UnaryOperation>
+_LIBCPP_HIDE_FROM_ABI auto __write_transformed(
+ _Iterator __first,
+ _Iterator __last,
+ output_iterator<const _CharT&> auto __out_it,
+ __format_spec::__parsed_specifications<_ParserCharT> __specs,
+ _UnaryOperation __op) -> decltype(__out_it) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__first <= __last, "Not a valid range");
+
+ ptrdiff_t __size = __last - __first;
+ if (__size >= __specs.__width_)
+ return __formatter::__transform(__first, __last, std::move(__out_it), __op);
+
+ __padding_size_result __padding = __formatter::__padding_size(__size, __specs.__width_, __specs.__alignment_);
+ __out_it = __formatter::__fill(std::move(__out_it), __padding.__before_, __specs.__fill_);
+ __out_it = __formatter::__transform(__first, __last, std::move(__out_it), __op);
+ return __formatter::__fill(std::move(__out_it), __padding.__after_, __specs.__fill_);
+}
+
+/// Writes a string using format's width estimation algorithm.
+///
+/// \pre !__specs.__has_precision()
+///
+/// \note When \c _LIBCPP_HAS_NO_UNICODE is defined the function assumes the
+/// input is ASCII.
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI auto __write_string_no_precision(
+ basic_string_view<_CharT> __str,
+ output_iterator<const _CharT&> auto __out_it,
+ __format_spec::__parsed_specifications<_CharT> __specs) -> decltype(__out_it) {
+ _LIBCPP_ASSERT_INTERNAL(!__specs.__has_precision(), "use __write_string");
+
+ // No padding -> copy the string
+ if (!__specs.__has_width())
+ return __formatter::__copy(__str, std::move(__out_it));
+
+ // Note when the estimated width is larger than size there's no padding. So
+ // there's no reason to get the real size when the estimate is larger than or
+ // equal to the minimum field width.
+ size_t __size =
+ __format_spec::__estimate_column_width(__str, __specs.__width_, __format_spec::__column_width_rounding::__up)
+ .__width_;
+ return __formatter::__write(__str, std::move(__out_it), __specs, __size);
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI int __truncate(basic_string_view<_CharT>& __str, int __precision) {
+ __format_spec::__column_width_result __result =
+ __format_spec::__estimate_column_width(__str, __precision, __format_spec::__column_width_rounding::__down);
+ __str = basic_string_view<_CharT>{__str.begin(), __result.__last_};
+ return __result.__width_;
+}
+
+} // namespace __formatter
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_FORMATTER_OUTPUT_H
diff --git a/libcxx/include/__cxx03/__format/formatter_pointer.h b/libcxx/include/__cxx03/__format/formatter_pointer.h
new file mode 100644
index 00000000000000..6941343efd91f9
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_pointer.h
@@ -0,0 +1,72 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_POINTER_H
+#define _LIBCPP___FORMAT_FORMATTER_POINTER_H
+
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/formatter_integral.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS __formatter_pointer {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_pointer);
+ __format_spec::__process_display_type_pointer(__parser_.__type_, "a pointer");
+ return __result;
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(const void* __ptr, _FormatContext& __ctx) const {
+ __format_spec::__parsed_specifications<_CharT> __specs = __parser_.__get_parsed_std_specifications(__ctx);
+ __specs.__std_.__alternate_form_ = true;
+ __specs.__std_.__type_ =
+ __specs.__std_.__type_ == __format_spec::__type::__pointer_upper_case
+ ? __format_spec::__type::__hexadecimal_upper_case
+ : __format_spec::__type::__hexadecimal_lower_case;
+
+ return __formatter::__format_integer(reinterpret_cast<uintptr_t>(__ptr), __ctx, __specs);
+ }
+
+ __format_spec::__parser<_CharT> __parser_;
+};
+
+// [format.formatter.spec]/2.4
+// For each charT, the pointer type specializations template<>
+// - struct formatter<nullptr_t, charT>;
+// - template<> struct formatter<void*, charT>;
+// - template<> struct formatter<const void*, charT>;
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<nullptr_t, _CharT> : public __formatter_pointer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<void*, _CharT> : public __formatter_pointer<_CharT> {};
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<const void*, _CharT> : public __formatter_pointer<_CharT> {};
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMATTER_POINTER_H
diff --git a/libcxx/include/__cxx03/__format/formatter_string.h b/libcxx/include/__cxx03/__format/formatter_string.h
new file mode 100644
index 00000000000000..347439fc8dff13
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_string.h
@@ -0,0 +1,150 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_STRING_H
+#define _LIBCPP___FORMAT_FORMATTER_STRING_H
+
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <__format/write_escaped.h>
+#include <string>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS __formatter_string {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_string);
+ __format_spec::__process_display_type_string(__parser_.__type_);
+ return __result;
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(basic_string_view<_CharT> __str, _FormatContext& __ctx) const {
+# if _LIBCPP_STD_VER >= 23
+ if (__parser_.__type_ == __format_spec::__type::__debug)
+ return __formatter::__format_escaped_string(__str, __ctx.out(), __parser_.__get_parsed_std_specifications(__ctx));
+# endif
+
+ return __formatter::__write_string(__str, __ctx.out(), __parser_.__get_parsed_std_specifications(__ctx));
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI constexpr void set_debug_format() { __parser_.__type_ = __format_spec::__type::__debug; }
+# endif
+
+ __format_spec::__parser<_CharT> __parser_{.__alignment_ = __format_spec::__alignment::__left};
+};
+
+// Formatter const char*.
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<const _CharT*, _CharT> : public __formatter_string<_CharT> {
+ using _Base = __formatter_string<_CharT>;
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(const _CharT* __str, _FormatContext& __ctx) const {
+ _LIBCPP_ASSERT_INTERNAL(__str, "The basic_format_arg constructor should have prevented an invalid pointer.");
+
+ __format_spec::__parsed_specifications<_CharT> __specs = _Base::__parser_.__get_parsed_std_specifications(__ctx);
+# if _LIBCPP_STD_VER >= 23
+ if (_Base::__parser_.__type_ == __format_spec::__type::__debug)
+ return __formatter::__format_escaped_string(basic_string_view<_CharT>{__str}, __ctx.out(), __specs);
+# endif
+
+ // When using a center or right alignment and the width option the length
+ // of __str must be known to add the padding upfront. This case is handled
+ // by the base class by converting the argument to a basic_string_view.
+ //
+ // When using left alignment and the width option the padding is added
+ // after outputting __str so the length can be determined while outputting
+ // __str. The same holds true for the precision, during outputting __str it
+ // can be validated whether the precision threshold has been reached. For
+ // now these optimizations aren't implemented. Instead the base class
+ // handles these options.
+ // TODO FMT Implement these improvements.
+ if (__specs.__has_width() || __specs.__has_precision())
+ return __formatter::__write_string(basic_string_view<_CharT>{__str}, __ctx.out(), __specs);
+
+ // No formatting required, copy the string to the output.
+ auto __out_it = __ctx.out();
+ while (*__str)
+ *__out_it++ = *__str++;
+ return __out_it;
+ }
+};
+
+// Formatter char*.
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<_CharT*, _CharT> : public formatter<const _CharT*, _CharT> {
+ using _Base = formatter<const _CharT*, _CharT>;
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(_CharT* __str, _FormatContext& __ctx) const {
+ return _Base::format(__str, __ctx);
+ }
+};
+
+// Formatter char[].
+template <__fmt_char_type _CharT, size_t _Size>
+struct _LIBCPP_TEMPLATE_VIS formatter<_CharT[_Size], _CharT> : public __formatter_string<_CharT> {
+ using _Base = __formatter_string<_CharT>;
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(const _CharT (&__str)[_Size], _FormatContext& __ctx) const {
+ return _Base::format(basic_string_view<_CharT>(__str, _Size), __ctx);
+ }
+};
+
+// Formatter std::string.
+template <__fmt_char_type _CharT, class _Traits, class _Allocator>
+struct _LIBCPP_TEMPLATE_VIS formatter<basic_string<_CharT, _Traits, _Allocator>, _CharT>
+ : public __formatter_string<_CharT> {
+ using _Base = __formatter_string<_CharT>;
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(const basic_string<_CharT, _Traits, _Allocator>& __str, _FormatContext& __ctx) const {
+ // Drop _Traits and _Allocator to have one std::basic_string formatter.
+ return _Base::format(basic_string_view<_CharT>(__str.data(), __str.size()), __ctx);
+ }
+};
+
+// Formatter std::string_view.
+template <__fmt_char_type _CharT, class _Traits>
+struct _LIBCPP_TEMPLATE_VIS formatter<basic_string_view<_CharT, _Traits>, _CharT> : public __formatter_string<_CharT> {
+ using _Base = __formatter_string<_CharT>;
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(basic_string_view<_CharT, _Traits> __str, _FormatContext& __ctx) const {
+ // Drop _Traits to have one std::basic_string_view formatter.
+ return _Base::format(basic_string_view<_CharT>(__str.data(), __str.size()), __ctx);
+ }
+};
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMATTER_STRING_H
diff --git a/libcxx/include/__cxx03/__format/formatter_tuple.h b/libcxx/include/__cxx03/__format/formatter_tuple.h
new file mode 100644
index 00000000000000..030097a8797dae
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/formatter_tuple.h
@@ -0,0 +1,150 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_FORMATTER_TUPLE_H
+#define _LIBCPP___FORMAT_FORMATTER_TUPLE_H
+
+#include <__algorithm/ranges_copy.h>
+#include <__chrono/statically_widen.h>
+#include <__config>
+#include <__format/buffer.h>
+#include <__format/concepts.h>
+#include <__format/format_context.h>
+#include <__format/format_error.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/integer_sequence.h>
+#include <__utility/pair.h>
+#include <string_view>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <__fmt_char_type _CharT, class _Tuple, formattable<_CharT>... _Args>
+struct _LIBCPP_TEMPLATE_VIS __formatter_tuple {
+ _LIBCPP_HIDE_FROM_ABI constexpr void set_separator(basic_string_view<_CharT> __separator) noexcept {
+ __separator_ = __separator;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ set_brackets(basic_string_view<_CharT> __opening_bracket, basic_string_view<_CharT> __closing_bracket) noexcept {
+ __opening_bracket_ = __opening_bracket;
+ __closing_bracket_ = __closing_bracket;
+ }
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ auto __begin = __parser_.__parse(__ctx, __format_spec::__fields_tuple);
+
+ auto __end = __ctx.end();
+ // Note 'n' is part of the type here
+ if (__parser_.__clear_brackets_)
+ set_brackets({}, {});
+ else if (__begin != __end && *__begin == _CharT('m')) {
+ if constexpr (sizeof...(_Args) == 2) {
+ set_separator(_LIBCPP_STATICALLY_WIDEN(_CharT, ": "));
+ set_brackets({}, {});
+ ++__begin;
+ } else
+ std::__throw_format_error("Type m requires a pair or a tuple with two elements");
+ }
+
+ if (__begin != __end && *__begin != _CharT('}'))
+ std::__throw_format_error("The format specifier should consume the input or end with a '}'");
+
+ __ctx.advance_to(__begin);
+
+ // [format.tuple]/7
+ // ... For each element e in underlying_, if e.set_debug_format()
+ // is a valid expression, calls e.set_debug_format().
+ std::__for_each_index_sequence(make_index_sequence<sizeof...(_Args)>(), [&]<size_t _Index> {
+ auto& __formatter = std::get<_Index>(__underlying_);
+ __formatter.parse(__ctx);
+ // Unlike the range_formatter we don't guard against evil parsers. Since
+ // this format-spec never has a format-spec for the underlying type
+ // adding the test would give additional overhead.
+ std::__set_debug_format(__formatter);
+ });
+
+ return __begin;
+ }
+
+ template <class _FormatContext>
+ typename _FormatContext::iterator _LIBCPP_HIDE_FROM_ABI
+ format(conditional_t<(formattable<const _Args, _CharT> && ...), const _Tuple&, _Tuple&> __tuple,
+ _FormatContext& __ctx) const {
+ __format_spec::__parsed_specifications<_CharT> __specs = __parser_.__get_parsed_std_specifications(__ctx);
+
+ if (!__specs.__has_width())
+ return __format_tuple(__tuple, __ctx);
+
+ // The size of the buffer needed is:
+ // - open bracket characters
+ // - close bracket character
+ // - n elements where every element may have a different size
+ // - (n -1) separators
+ // The size of the element is hard to predict, knowing the type helps but
+ // it depends on the format-spec. As an initial estimate we guess 6
+ // characters.
+ // Typically both brackets are 1 character and the separator is 2
+ // characters. Which means there will be
+ // (n - 1) * 2 + 1 + 1 = n * 2 character
+ // So estimate 8 times the range size as buffer.
+ __format::__retarget_buffer<_CharT> __buffer{8 * tuple_size_v<_Tuple>};
+ basic_format_context<typename __format::__retarget_buffer<_CharT>::__iterator, _CharT> __c{
+ __buffer.__make_output_iterator(), __ctx};
+
+ __format_tuple(__tuple, __c);
+
+ return __formatter::__write_string_no_precision(basic_string_view{__buffer.__view()}, __ctx.out(), __specs);
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator __format_tuple(auto&& __tuple, _FormatContext& __ctx) const {
+ __ctx.advance_to(std::ranges::copy(__opening_bracket_, __ctx.out()).out);
+
+ std::__for_each_index_sequence(make_index_sequence<sizeof...(_Args)>(), [&]<size_t _Index> {
+ if constexpr (_Index)
+ __ctx.advance_to(std::ranges::copy(__separator_, __ctx.out()).out);
+ __ctx.advance_to(std::get<_Index>(__underlying_).format(std::get<_Index>(__tuple), __ctx));
+ });
+
+ return std::ranges::copy(__closing_bracket_, __ctx.out()).out;
+ }
+
+ __format_spec::__parser<_CharT> __parser_{.__alignment_ = __format_spec::__alignment::__left};
+
+private:
+ tuple<formatter<remove_cvref_t<_Args>, _CharT>...> __underlying_;
+ basic_string_view<_CharT> __separator_ = _LIBCPP_STATICALLY_WIDEN(_CharT, ", ");
+ basic_string_view<_CharT> __opening_bracket_ = _LIBCPP_STATICALLY_WIDEN(_CharT, "(");
+ basic_string_view<_CharT> __closing_bracket_ = _LIBCPP_STATICALLY_WIDEN(_CharT, ")");
+};
+
+template <__fmt_char_type _CharT, formattable<_CharT>... _Args>
+struct _LIBCPP_TEMPLATE_VIS formatter<pair<_Args...>, _CharT>
+ : public __formatter_tuple<_CharT, pair<_Args...>, _Args...> {};
+
+template <__fmt_char_type _CharT, formattable<_CharT>... _Args>
+struct _LIBCPP_TEMPLATE_VIS formatter<tuple<_Args...>, _CharT>
+ : public __formatter_tuple<_CharT, tuple<_Args...>, _Args...> {};
+
+#endif //_LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_FORMATTER_TUPLE_H
diff --git a/libcxx/include/__cxx03/__format/indic_conjunct_break_table.h b/libcxx/include/__cxx03/__format/indic_conjunct_break_table.h
new file mode 100644
index 00000000000000..44521d27498c3c
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/indic_conjunct_break_table.h
@@ -0,0 +1,350 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// WARNING, this entire header is generated by
+// utils/generate_indic_conjunct_break_table.py
+// DO NOT MODIFY!
+
+// UNICODE, INC. LICENSE AGREEMENT - DATA FILES AND SOFTWARE
+//
+// See Terms of Use <https://www.unicode.org/copyright.html>
+// for definitions of Unicode Inc.'s Data Files and Software.
+//
+// NOTICE TO USER: Carefully read the following legal agreement.
+// BY DOWNLOADING, INSTALLING, COPYING OR OTHERWISE USING UNICODE INC.'S
+// DATA FILES ("DATA FILES"), AND/OR SOFTWARE ("SOFTWARE"),
+// YOU UNEQUIVOCALLY ACCEPT, AND AGREE TO BE BOUND BY, ALL OF THE
+// TERMS AND CONDITIONS OF THIS AGREEMENT.
+// IF YOU DO NOT AGREE, DO NOT DOWNLOAD, INSTALL, COPY, DISTRIBUTE OR USE
+// THE DATA FILES OR SOFTWARE.
+//
+// COPYRIGHT AND PERMISSION NOTICE
+//
+// Copyright (c) 1991-2022 Unicode, Inc. All rights reserved.
+// Distributed under the Terms of Use in https://www.unicode.org/copyright.html.
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of the Unicode data files and any associated documentation
+// (the "Data Files") or Unicode software and any associated documentation
+// (the "Software") to deal in the Data Files or Software
+// without restriction, including without limitation the rights to use,
+// copy, modify, merge, publish, distribute, and/or sell copies of
+// the Data Files or Software, and to permit persons to whom the Data Files
+// or Software are furnished to do so, provided that either
+// (a) this copyright and permission notice appear with all copies
+// of the Data Files or Software, or
+// (b) this copyright and permission notice appear in associated
+// Documentation.
+//
+// THE DATA FILES AND SOFTWARE ARE PROVIDED "AS IS", WITHOUT WARRANTY OF
+// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+// WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+// IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS
+// NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL
+// DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+// DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THE DATA FILES OR SOFTWARE.
+//
+// Except as contained in this notice, the name of a copyright holder
+// shall not be used in advertising or otherwise to promote the sale,
+// use or other dealings in these Data Files or Software without prior
+// written authorization of the copyright holder.
+
+#ifndef _LIBCPP___FORMAT_INDIC_CONJUNCT_BREAK_TABLE_H
+#define _LIBCPP___FORMAT_INDIC_CONJUNCT_BREAK_TABLE_H
+
+#include <__algorithm/ranges_upper_bound.h>
+#include <__config>
+#include <__iterator/access.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __indic_conjunct_break {
+
+enum class __property : uint8_t {
+ // Values generated from the data files.
+ __Consonant,
+ __Extend,
+ __Linker,
+
+ // The code unit has none of above properties.
+ __none
+};
+
+/// The entries of the indic conjunct break property table.
+///
+/// The data is generated from
+/// - https://www.unicode.org/Public/UCD/latest/ucd/DerivedCoreProperties.txt
+///
+/// The data has 3 values
+/// - bits [0, 1] The property. One of the values generated from the datafiles
+/// of \ref __property
+/// - bits [2, 10] The size of the range.
+/// - bits [11, 31] The lower bound code point of the range. The upper bound of
+/// the range is lower bound + size.
+///
+/// The 9 bits for the size allow a maximum range of 512 elements. Some ranges
+/// in the Unicode tables are larger. They are stored in multiple consecutive
+/// ranges in the data table. An alternative would be to store the sizes in a
+/// separate 16-bit value. The original MSVC STL code had such an approach, but
+/// this approach uses less space for the data and is about 4% faster in the
+/// following benchmark.
+/// libcxx/benchmarks/std_format_spec_string_unicode.bench.cpp
+// clang-format off
+_LIBCPP_HIDE_FROM_ABI inline constexpr uint32_t __entries[201] = {
+ 0x00180139,
+ 0x001a807d,
+ 0x00241811,
+ 0x002c88b1,
+ 0x002df801,
+ 0x002e0805,
+ 0x002e2005,
+ 0x002e3801,
+ 0x00308029,
+ 0x00325851,
+ 0x00338001,
+ 0x0036b019,
+ 0x0036f815,
+ 0x00373805,
+ 0x0037500d,
+ 0x00388801,
+ 0x00398069,
+ 0x003f5821,
+ 0x003fe801,
+ 0x0040b00d,
+ 0x0040d821,
+ 0x00412809,
+ 0x00414811,
+ 0x0042c809,
+ 0x0044c01d,
+ 0x0046505d,
+ 0x00471871,
+ 0x0048a890,
+ 0x0049e001,
+ 0x004a6802,
+ 0x004a880d,
+ 0x004ac01c,
+ 0x004bc01c,
+ 0x004ca84c,
+ 0x004d5018,
+ 0x004d9000,
+ 0x004db00c,
+ 0x004de001,
+ 0x004e6802,
+ 0x004ee004,
+ 0x004ef800,
+ 0x004f8004,
+ 0x004ff001,
+ 0x0051e001,
+ 0x0054a84c,
+ 0x00555018,
+ 0x00559004,
+ 0x0055a810,
+ 0x0055e001,
+ 0x00566802,
+ 0x0057c800,
+ 0x0058a84c,
+ 0x00595018,
+ 0x00599004,
+ 0x0059a810,
+ 0x0059e001,
+ 0x005a6802,
+ 0x005ae004,
+ 0x005af800,
+ 0x005b8800,
+ 0x0060a84c,
+ 0x0061503c,
+ 0x0061e001,
+ 0x00626802,
+ 0x0062a805,
+ 0x0062c008,
+ 0x0065e001,
+ 0x0068a894,
+ 0x0069d805,
+ 0x006a6802,
+ 0x0071c009,
+ 0x0072400d,
+ 0x0075c009,
+ 0x0076400d,
+ 0x0078c005,
+ 0x0079a801,
+ 0x0079b801,
+ 0x0079c801,
+ 0x007b8805,
+ 0x007ba001,
+ 0x007bd00d,
+ 0x007c0001,
+ 0x007c1009,
+ 0x007c3005,
+ 0x007e3001,
+ 0x0081b801,
+ 0x0081c805,
+ 0x00846801,
+ 0x009ae809,
+ 0x00b8a001,
+ 0x00be9001,
+ 0x00bee801,
+ 0x00c54801,
+ 0x00c9c809,
+ 0x00d0b805,
+ 0x00d30001,
+ 0x00d3a81d,
+ 0x00d3f801,
+ 0x00d58035,
+ 0x00d5f83d,
+ 0x00d9a001,
+ 0x00db5821,
+ 0x00dd5801,
+ 0x00df3001,
+ 0x00e1b801,
+ 0x00e68009,
+ 0x00e6a031,
+ 0x00e71019,
+ 0x00e76801,
+ 0x00e7a001,
+ 0x00e7c005,
+ 0x00ee00fd,
+ 0x01006801,
+ 0x01068031,
+ 0x01070801,
+ 0x0107282d,
+ 0x01677809,
+ 0x016bf801,
+ 0x016f007d,
+ 0x01815015,
+ 0x0184c805,
+ 0x05337801,
+ 0x0533a025,
+ 0x0534f005,
+ 0x05378005,
+ 0x05416001,
+ 0x05470045,
+ 0x05495809,
+ 0x054d9801,
+ 0x05558001,
+ 0x05559009,
+ 0x0555b805,
+ 0x0555f005,
+ 0x05560801,
+ 0x0557b001,
+ 0x055f6801,
+ 0x07d8f001,
+ 0x07f1003d,
+ 0x080fe801,
+ 0x08170001,
+ 0x081bb011,
+ 0x08506801,
+ 0x08507801,
+ 0x0851c009,
+ 0x0851f801,
+ 0x08572805,
+ 0x0869200d,
+ 0x08755805,
+ 0x0877e809,
+ 0x087a3029,
+ 0x087c100d,
+ 0x08838001,
+ 0x0883f801,
+ 0x0885d001,
+ 0x08880009,
+ 0x08899805,
+ 0x088b9801,
+ 0x088e5001,
+ 0x0891b001,
+ 0x08974805,
+ 0x0899d805,
+ 0x089b3019,
+ 0x089b8011,
+ 0x08a23001,
+ 0x08a2f001,
+ 0x08a61801,
+ 0x08ae0001,
+ 0x08b5b801,
+ 0x08b95801,
+ 0x08c1d001,
+ 0x08c9f001,
+ 0x08ca1801,
+ 0x08d1a001,
+ 0x08d23801,
+ 0x08d4c801,
+ 0x08ea1001,
+ 0x08ea2005,
+ 0x08ecb801,
+ 0x08fa1001,
+ 0x0b578011,
+ 0x0b598019,
+ 0x0de4f001,
+ 0x0e8b2801,
+ 0x0e8b3809,
+ 0x0e8b7011,
+ 0x0e8bd81d,
+ 0x0e8c2819,
+ 0x0e8d500d,
+ 0x0e921009,
+ 0x0f000019,
+ 0x0f004041,
+ 0x0f00d819,
+ 0x0f011805,
+ 0x0f013011,
+ 0x0f047801,
+ 0x0f098019,
+ 0x0f157001,
+ 0x0f17600d,
+ 0x0f27600d,
+ 0x0f468019,
+ 0x0f4a2019};
+// clang-format on
+
+/// Returns the indic conjuct break property of a code point.
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __property __get_property(const char32_t __code_point) noexcept {
+ // The algorithm searches for the upper bound of the range and, when found,
+ // steps back one entry. This algorithm is used since the code point can be
+ // anywhere in the range. After a lower bound is found the next step is to
+ // compare whether the code unit is indeed in the range.
+ //
+ // Since the entry contains a code unit, size, and property the code point
+ // being sought needs to be adjusted. Just shifting the code point to the
+ // proper position doesn't work; suppose an entry has property 0, size 1,
+ // and lower bound 3. This results in the entry 0x1810.
+ // When searching for code point 3 it will search for 0x1800, find 0x1810
+ // and moves to the previous entry. Thus the lower bound value will never
+ // be found.
+ // The simple solution is to set the bits belonging to the property and
+ // size. Then the upper bound for code point 3 will return the entry after
+ // 0x1810. After moving to the previous entry the algorithm arrives at the
+ // correct entry.
+ ptrdiff_t __i = std::ranges::upper_bound(__entries, (__code_point << 11) | 0x7ffu) - __entries;
+ if (__i == 0)
+ return __property::__none;
+
+ --__i;
+ uint32_t __upper_bound = (__entries[__i] >> 11) + ((__entries[__i] >> 2) & 0b1'1111'1111);
+ if (__code_point <= __upper_bound)
+ return static_cast<__property>(__entries[__i] & 0b11);
+
+ return __property::__none;
+}
+
+} // namespace __indic_conjunct_break
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_INDIC_CONJUNCT_BREAK_TABLE_H
diff --git a/libcxx/include/__cxx03/__format/parser_std_format_spec.h b/libcxx/include/__cxx03/__format/parser_std_format_spec.h
new file mode 100644
index 00000000000000..150bdde89f3b39
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/parser_std_format_spec.h
@@ -0,0 +1,1172 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_PARSER_STD_FORMAT_SPEC_H
+#define _LIBCPP___FORMAT_PARSER_STD_FORMAT_SPEC_H
+
+/// \file Contains the std-format-spec parser.
+///
+/// Most of the code can be reused in the chrono-format-spec.
+/// This header has some support for the chrono-format-spec since it doesn't
+/// affect the std-format-spec.
+
+#include <__algorithm/copy_n.h>
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__concepts/arithmetic.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/format_arg.h>
+#include <__format/format_error.h>
+#include <__format/format_parse_context.h>
+#include <__format/format_string.h>
+#include <__format/unicode.h>
+#include <__format/width_estimation_table.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h> // iter_value_t
+#include <__memory/addressof.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <__variant/monostate.h>
+#include <cstdint>
+#include <string>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __format_spec {
+
+_LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI inline void
+__throw_invalid_option_format_error(const char* __id, const char* __option) {
+ std::__throw_format_error(
+ (string("The format specifier for ") + __id + " does not allow the " + __option + " option").c_str());
+}
+
+_LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI inline void __throw_invalid_type_format_error(const char* __id) {
+ std::__throw_format_error(
+ (string("The type option contains an invalid value for ") + __id + " formatting argument").c_str());
+}
+
+template <contiguous_iterator _Iterator, class _ParseContext>
+_LIBCPP_HIDE_FROM_ABI constexpr __format::__parse_number_result<_Iterator>
+__parse_arg_id(_Iterator __begin, _Iterator __end, _ParseContext& __ctx) {
+ using _CharT = iter_value_t<_Iterator>;
+ // This function is a wrapper to call the real parser. But it does the
+ // validation for the pre-conditions and post-conditions.
+ if (__begin == __end)
+ std::__throw_format_error("End of input while parsing an argument index");
+
+ __format::__parse_number_result __r = __format::__parse_arg_id(__begin, __end, __ctx);
+
+ if (__r.__last == __end || *__r.__last != _CharT('}'))
+ std::__throw_format_error("The argument index is invalid");
+
+ ++__r.__last;
+ return __r;
+}
+
+template <class _Context>
+_LIBCPP_HIDE_FROM_ABI constexpr uint32_t __substitute_arg_id(basic_format_arg<_Context> __format_arg) {
+ // [format.string.std]/8
+ // If the corresponding formatting argument is not of integral type...
+ // This wording allows char and bool too. LWG-3720 changes the wording to
+ // If the corresponding formatting argument is not of standard signed or
+ // unsigned integer type,
+ // This means the 128-bit will not be valid anymore.
+ // TODO FMT Verify this resolution is accepted and add a test to verify
+ // 128-bit integrals fail and switch to visit_format_arg.
+ return std::__visit_format_arg(
+ [](auto __arg) -> uint32_t {
+ using _Type = decltype(__arg);
+ if constexpr (same_as<_Type, monostate>)
+ std::__throw_format_error("The argument index value is too large for the number of arguments supplied");
+
+ // [format.string.std]/8
+ // If { arg-idopt } is used in a width or precision, the value of the
+ // corresponding formatting argument is used in its place. If the
+ // corresponding formatting argument is not of standard signed or unsigned
+ // integer type, or its value is negative for precision or non-positive for
+ // width, an exception of type format_error is thrown.
+ //
+ // When an integral is used in a format function, it is stored as one of
+ // the types checked below. Other integral types are promoted. For example,
+ // a signed char is stored as an int.
+ if constexpr (same_as<_Type, int> || same_as<_Type, unsigned int> || //
+ same_as<_Type, long long> || same_as<_Type, unsigned long long>) {
+ if constexpr (signed_integral<_Type>) {
+ if (__arg < 0)
+ std::__throw_format_error("An argument index may not have a negative value");
+ }
+
+ using _CT = common_type_t<_Type, decltype(__format::__number_max)>;
+ if (static_cast<_CT>(__arg) > static_cast<_CT>(__format::__number_max))
+ std::__throw_format_error("The value of the argument index exceeds its maximum value");
+
+ return __arg;
+ } else
+ std::__throw_format_error("Replacement argument isn't a standard signed or unsigned integer type");
+ },
+ __format_arg);
+}
+
+/// These fields are a filter for which elements to parse.
+///
+/// They default to false so when a new field is added it needs to be opted in
+/// explicitly.
+struct _LIBCPP_HIDE_FROM_ABI __fields {
+ uint16_t __sign_ : 1 {false};
+ uint16_t __alternate_form_ : 1 {false};
+ uint16_t __zero_padding_ : 1 {false};
+ uint16_t __precision_ : 1 {false};
+ uint16_t __locale_specific_form_ : 1 {false};
+ uint16_t __type_ : 1 {false};
+ // Determines the valid values for fill.
+ //
+ // Originally the fill could be any character except { and }. Range-based
+ // formatters use the colon to mark the beginning of the
+ // underlying-format-spec. To avoid parsing ambiguities these formatter
+ // specializations prohibit the use of the colon as a fill character.
+ uint16_t __use_range_fill_ : 1 {false};
+ uint16_t __clear_brackets_ : 1 {false};
+ uint16_t __consume_all_ : 1 {false};
+};
+
+// By not placing this constant in the formatter class it's not duplicated for
+// char and wchar_t.
+inline constexpr __fields __fields_bool{.__locale_specific_form_ = true, .__type_ = true, .__consume_all_ = true};
+inline constexpr __fields __fields_integral{
+ .__sign_ = true,
+ .__alternate_form_ = true,
+ .__zero_padding_ = true,
+ .__locale_specific_form_ = true,
+ .__type_ = true,
+ .__consume_all_ = true};
+inline constexpr __fields __fields_floating_point{
+ .__sign_ = true,
+ .__alternate_form_ = true,
+ .__zero_padding_ = true,
+ .__precision_ = true,
+ .__locale_specific_form_ = true,
+ .__type_ = true,
+ .__consume_all_ = true};
+inline constexpr __fields __fields_string{.__precision_ = true, .__type_ = true, .__consume_all_ = true};
+inline constexpr __fields __fields_pointer{.__zero_padding_ = true, .__type_ = true, .__consume_all_ = true};
+
+# if _LIBCPP_STD_VER >= 23
+inline constexpr __fields __fields_tuple{.__use_range_fill_ = true, .__clear_brackets_ = true};
+inline constexpr __fields __fields_range{.__use_range_fill_ = true, .__clear_brackets_ = true};
+inline constexpr __fields __fields_fill_align_width{};
+# endif
+
+enum class __alignment : uint8_t {
+ /// No alignment is set in the format string.
+ __default,
+ __left,
+ __center,
+ __right,
+ __zero_padding
+};
+
+enum class __sign : uint8_t {
+ /// No sign is set in the format string.
+ ///
+ /// The sign isn't allowed for certain format-types. By using this value
+ /// it's possible to detect whether or not the user explicitly set the sign
+ /// flag. For formatting purposes it behaves the same as \ref __minus.
+ __default,
+ __minus,
+ __plus,
+ __space
+};
+
+enum class __type : uint8_t {
+ __default = 0,
+ __string,
+ __binary_lower_case,
+ __binary_upper_case,
+ __octal,
+ __decimal,
+ __hexadecimal_lower_case,
+ __hexadecimal_upper_case,
+ __pointer_lower_case,
+ __pointer_upper_case,
+ __char,
+ __hexfloat_lower_case,
+ __hexfloat_upper_case,
+ __scientific_lower_case,
+ __scientific_upper_case,
+ __fixed_lower_case,
+ __fixed_upper_case,
+ __general_lower_case,
+ __general_upper_case,
+ __debug
+};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr uint32_t __create_type_mask(__type __t) {
+ uint32_t __shift = static_cast<uint32_t>(__t);
+ if (__shift == 0)
+ return 1;
+
+ if (__shift > 31)
+ std::__throw_format_error("The type does not fit in the mask");
+
+ return 1 << __shift;
+}
+
+inline constexpr uint32_t __type_mask_integer =
+ __create_type_mask(__type::__binary_lower_case) | //
+ __create_type_mask(__type::__binary_upper_case) | //
+ __create_type_mask(__type::__decimal) | //
+ __create_type_mask(__type::__octal) | //
+ __create_type_mask(__type::__hexadecimal_lower_case) | //
+ __create_type_mask(__type::__hexadecimal_upper_case);
+
+struct __std {
+ __alignment __alignment_ : 3;
+ __sign __sign_ : 2;
+ bool __alternate_form_ : 1;
+ bool __locale_specific_form_ : 1;
+ __type __type_;
+};
+
+struct __chrono {
+ __alignment __alignment_ : 3;
+ bool __locale_specific_form_ : 1;
+ bool __hour_ : 1;
+ bool __weekday_name_ : 1;
+ bool __weekday_ : 1;
+ bool __day_of_year_ : 1;
+ bool __week_of_year_ : 1;
+ bool __month_name_ : 1;
+};
+
+// The fill UCS scalar value.
+//
+// This is always an array, with 1, 2, or 4 elements.
+// The size of the data structure is always 32-bits.
+template <class _CharT>
+struct __code_point;
+
+template <>
+struct __code_point<char> {
+ char __data[4] = {' '};
+};
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+struct __code_point<wchar_t> {
+ wchar_t __data[4 / sizeof(wchar_t)] = {L' '};
+};
+# endif
+
+/// Contains the parsed formatting specifications.
+///
+/// This contains information for both the std-format-spec and the
+/// chrono-format-spec. This results in some unused members for both
+/// specifications. However these unused members don't increase the size
+/// of the structure.
+///
+/// This struct doesn't cross ABI boundaries so its layout doesn't need to be
+/// kept stable.
+template <class _CharT>
+struct __parsed_specifications {
+ union {
+ // The field __alignment_ is the first element in __std_ and __chrono_.
+ // This allows the code to always inspect this value regards which member
+ // of the union is the active member [class.union.general]/2.
+ //
+ // This is needed since the generic output routines handle the alignment of
+ // the output.
+ __alignment __alignment_ : 3;
+ __std __std_;
+ __chrono __chrono_;
+ };
+
+ /// The requested width.
+ ///
+ /// When the format-spec used an arg-id for this field it has already been
+ /// replaced with the value of that arg-id.
+ int32_t __width_;
+
+ /// The requested precision.
+ ///
+ /// When the format-spec used an arg-id for this field it has already been
+ /// replaced with the value of that arg-id.
+ int32_t __precision_;
+
+ __code_point<_CharT> __fill_;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __has_width() const { return __width_ > 0; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __has_precision() const { return __precision_ >= 0; }
+};
+
+// Validate the struct is small and cheap to copy since the struct is passed by
+// value in formatting functions.
+static_assert(sizeof(__parsed_specifications<char>) == 16);
+static_assert(is_trivially_copyable_v<__parsed_specifications<char>>);
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+static_assert(sizeof(__parsed_specifications<wchar_t>) == 16);
+static_assert(is_trivially_copyable_v<__parsed_specifications<wchar_t>>);
+# endif
+
+/// The parser for the std-format-spec.
+///
+/// Note this class is a member of std::formatter specializations. It's
+/// expected developers will create their own formatter specializations that
+/// inherit from the std::formatter specializations. This means this class
+/// must be ABI stable. To aid the stability the unused bits in the class are
+/// set to zero. That way they can be repurposed if a future revision of the
+/// Standards adds new fields to std-format-spec.
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS __parser {
+public:
+ // Parses the format specification.
+ //
+ // Depending on whether the parsing is done compile-time or run-time
+ // the method slightly differs.
+ // - Only parses a field when it is in the __fields. Accepting all
+ // fields and then validating the valid ones has a performance impact.
+ // This is faster but gives slighly worse error messages.
+ // - At compile-time when a field is not accepted the parser will still
+ // parse it and give an error when it's present. This gives a more
+ // accurate error.
+ // The idea is that most times the format instead of the vformat
+ // functions are used. In that case the error will be detected during
+ // compilation and there is no need to pay for the run-time overhead.
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator __parse(_ParseContext& __ctx, __fields __fields) {
+ auto __begin = __ctx.begin();
+ auto __end = __ctx.end();
+ if (__begin == __end || *__begin == _CharT('}') || (__fields.__use_range_fill_ && *__begin == _CharT(':')))
+ return __begin;
+
+ if (__parse_fill_align(__begin, __end) && __begin == __end)
+ return __begin;
+
+ if (__fields.__sign_) {
+ if (__parse_sign(__begin) && __begin == __end)
+ return __begin;
+ } else if (std::is_constant_evaluated() && __parse_sign(__begin)) {
+ std::__throw_format_error("The format specification does not allow the sign option");
+ }
+
+ if (__fields.__alternate_form_) {
+ if (__parse_alternate_form(__begin) && __begin == __end)
+ return __begin;
+ } else if (std::is_constant_evaluated() && __parse_alternate_form(__begin)) {
+ std::__throw_format_error("The format specifier does not allow the alternate form option");
+ }
+
+ if (__fields.__zero_padding_) {
+ if (__parse_zero_padding(__begin) && __begin == __end)
+ return __begin;
+ } else if (std::is_constant_evaluated() && __parse_zero_padding(__begin)) {
+ std::__throw_format_error("The format specifier does not allow the zero-padding option");
+ }
+
+ if (__parse_width(__begin, __end, __ctx) && __begin == __end)
+ return __begin;
+
+ if (__fields.__precision_) {
+ if (__parse_precision(__begin, __end, __ctx) && __begin == __end)
+ return __begin;
+ } else if (std::is_constant_evaluated() && __parse_precision(__begin, __end, __ctx)) {
+ std::__throw_format_error("The format specifier does not allow the precision option");
+ }
+
+ if (__fields.__locale_specific_form_) {
+ if (__parse_locale_specific_form(__begin) && __begin == __end)
+ return __begin;
+ } else if (std::is_constant_evaluated() && __parse_locale_specific_form(__begin)) {
+ std::__throw_format_error("The format specifier does not allow the locale-specific form option");
+ }
+
+ if (__fields.__clear_brackets_) {
+ if (__parse_clear_brackets(__begin) && __begin == __end)
+ return __begin;
+ } else if (std::is_constant_evaluated() && __parse_clear_brackets(__begin)) {
+ std::__throw_format_error("The format specifier does not allow the n option");
+ }
+
+ if (__fields.__type_)
+ __parse_type(__begin);
+
+ if (!__fields.__consume_all_)
+ return __begin;
+
+ if (__begin != __end && *__begin != _CharT('}'))
+ std::__throw_format_error("The format specifier should consume the input or end with a '}'");
+
+ return __begin;
+ }
+
+ // Validates the selected the parsed data.
+ //
+ // The valid fields in the parser may depend on the display type
+ // selected. But the type is the last optional field, so by the time
+ // it's known an option can't be used, it already has been parsed.
+ // This does the validation again.
+ //
+ // For example an integral may have a sign, zero-padding, or alternate
+ // form when the type option is not 'c'. So the generic approach is:
+ //
+ // typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_integral);
+ // if (__parser.__type_ == __format_spec::__type::__char) {
+ // __parser.__validate((__format_spec::__fields_bool, "an integer");
+ // ... // more char adjustments
+ // } else {
+ // ... // validate an integral type.
+ // }
+ //
+ // For some types all valid options need a second validation run, like
+ // boolean types.
+ //
+ // Depending on whether the validation is done at compile-time or
+ // run-time the error differs
+ // - run-time the exception is thrown and contains the type of field
+ // being validated.
+ // - at compile-time the line with `std::__throw_format_error` is shown
+ // in the output. In that case it's important for the error to be on one
+ // line.
+ // Note future versions of C++ may allow better compile-time error
+ // reporting.
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ __validate(__fields __fields, const char* __id, uint32_t __type_mask = -1) const {
+ if (!__fields.__sign_ && __sign_ != __sign::__default) {
+ if (std::is_constant_evaluated())
+ std::__throw_format_error("The format specifier does not allow the sign option");
+ else
+ __format_spec::__throw_invalid_option_format_error(__id, "sign");
+ }
+
+ if (!__fields.__alternate_form_ && __alternate_form_) {
+ if (std::is_constant_evaluated())
+ std::__throw_format_error("The format specifier does not allow the alternate form option");
+ else
+ __format_spec::__throw_invalid_option_format_error(__id, "alternate form");
+ }
+
+ if (!__fields.__zero_padding_ && __alignment_ == __alignment::__zero_padding) {
+ if (std::is_constant_evaluated())
+ std::__throw_format_error("The format specifier does not allow the zero-padding option");
+ else
+ __format_spec::__throw_invalid_option_format_error(__id, "zero-padding");
+ }
+
+ if (!__fields.__precision_ && __precision_ != -1) { // Works both when the precision has a value or an arg-id.
+ if (std::is_constant_evaluated())
+ std::__throw_format_error("The format specifier does not allow the precision option");
+ else
+ __format_spec::__throw_invalid_option_format_error(__id, "precision");
+ }
+
+ if (!__fields.__locale_specific_form_ && __locale_specific_form_) {
+ if (std::is_constant_evaluated())
+ std::__throw_format_error("The format specifier does not allow the locale-specific form option");
+ else
+ __format_spec::__throw_invalid_option_format_error(__id, "locale-specific form");
+ }
+
+ if ((__create_type_mask(__type_) & __type_mask) == 0) {
+ if (std::is_constant_evaluated())
+ std::__throw_format_error("The format specifier uses an invalid value for the type option");
+ else
+ __format_spec::__throw_invalid_type_format_error(__id);
+ }
+ }
+
+ /// \returns the `__parsed_specifications` with the resolved dynamic sizes..
+ _LIBCPP_HIDE_FROM_ABI __parsed_specifications<_CharT> __get_parsed_std_specifications(auto& __ctx) const {
+ return __parsed_specifications<_CharT>{
+ .__std_ = __std{.__alignment_ = __alignment_,
+ .__sign_ = __sign_,
+ .__alternate_form_ = __alternate_form_,
+ .__locale_specific_form_ = __locale_specific_form_,
+ .__type_ = __type_},
+ .__width_{__get_width(__ctx)},
+ .__precision_{__get_precision(__ctx)},
+ .__fill_{__fill_}};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __parsed_specifications<_CharT> __get_parsed_chrono_specifications(auto& __ctx) const {
+ return __parsed_specifications<_CharT>{
+ .__chrono_ =
+ __chrono{.__alignment_ = __alignment_,
+ .__locale_specific_form_ = __locale_specific_form_,
+ .__hour_ = __hour_,
+ .__weekday_name_ = __weekday_name_,
+ .__weekday_ = __weekday_,
+ .__day_of_year_ = __day_of_year_,
+ .__week_of_year_ = __week_of_year_,
+ .__month_name_ = __month_name_},
+ .__width_{__get_width(__ctx)},
+ .__precision_{__get_precision(__ctx)},
+ .__fill_{__fill_}};
+ }
+
+ __alignment __alignment_ : 3 {__alignment::__default};
+ __sign __sign_ : 2 {__sign::__default};
+ bool __alternate_form_ : 1 {false};
+ bool __locale_specific_form_ : 1 {false};
+ bool __clear_brackets_ : 1 {false};
+ __type __type_{__type::__default};
+
+ // These flags are only used for formatting chrono. Since the struct has
+ // padding space left it's added to this structure.
+ bool __hour_ : 1 {false};
+
+ bool __weekday_name_ : 1 {false};
+ bool __weekday_ : 1 {false};
+
+ bool __day_of_year_ : 1 {false};
+ bool __week_of_year_ : 1 {false};
+
+ bool __month_name_ : 1 {false};
+
+ uint8_t __reserved_0_ : 2 {0};
+ uint8_t __reserved_1_ : 6 {0};
+ // These two flags are only used internally and not part of the
+ // __parsed_specifications. Therefore put them at the end.
+ bool __width_as_arg_ : 1 {false};
+ bool __precision_as_arg_ : 1 {false};
+
+ /// The requested width, either the value or the arg-id.
+ int32_t __width_{0};
+
+ /// The requested precision, either the value or the arg-id.
+ int32_t __precision_{-1};
+
+ __code_point<_CharT> __fill_{};
+
+private:
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_alignment(_CharT __c) {
+ switch (__c) {
+ case _CharT('<'):
+ __alignment_ = __alignment::__left;
+ return true;
+
+ case _CharT('^'):
+ __alignment_ = __alignment::__center;
+ return true;
+
+ case _CharT('>'):
+ __alignment_ = __alignment::__right;
+ return true;
+ }
+ return false;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __validate_fill_character(_CharT __fill) {
+ // The forbidden fill characters all code points formed from a single code unit, thus the
+ // check can be omitted when more code units are used.
+ if (__fill == _CharT('{'))
+ std::__throw_format_error("The fill option contains an invalid value");
+ }
+
+# ifndef _LIBCPP_HAS_NO_UNICODE
+ // range-fill and tuple-fill are identical
+ template <contiguous_iterator _Iterator>
+ requires same_as<_CharT, char>
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ || (same_as<_CharT, wchar_t> && sizeof(wchar_t) == 2)
+# endif
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_fill_align(_Iterator& __begin, _Iterator __end) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __begin != __end,
+ "when called with an empty input the function will cause "
+ "undefined behavior by evaluating data not in the input");
+ __unicode::__code_point_view<_CharT> __view{__begin, __end};
+ __unicode::__consume_result __consumed = __view.__consume();
+ if (__consumed.__status != __unicode::__consume_result::__ok)
+ std::__throw_format_error("The format specifier contains malformed Unicode characters");
+
+ if (__view.__position() < __end && __parse_alignment(*__view.__position())) {
+ ptrdiff_t __code_units = __view.__position() - __begin;
+ if (__code_units == 1)
+ // The forbidden fill characters all are code points encoded
+ // in one code unit, thus the check can be omitted when more
+ // code units are used.
+ __validate_fill_character(*__begin);
+
+ std::copy_n(__begin, __code_units, std::addressof(__fill_.__data[0]));
+ __begin += __code_units + 1;
+ return true;
+ }
+
+ if (!__parse_alignment(*__begin))
+ return false;
+
+ ++__begin;
+ return true;
+ }
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ template <contiguous_iterator _Iterator>
+ requires(same_as<_CharT, wchar_t> && sizeof(wchar_t) == 4)
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_fill_align(_Iterator& __begin, _Iterator __end) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __begin != __end,
+ "when called with an empty input the function will cause "
+ "undefined behavior by evaluating data not in the input");
+ if (__begin + 1 != __end && __parse_alignment(*(__begin + 1))) {
+ if (!__unicode::__is_scalar_value(*__begin))
+ std::__throw_format_error("The fill option contains an invalid value");
+
+ __validate_fill_character(*__begin);
+
+ __fill_.__data[0] = *__begin;
+ __begin += 2;
+ return true;
+ }
+
+ if (!__parse_alignment(*__begin))
+ return false;
+
+ ++__begin;
+ return true;
+ }
+
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+# else // _LIBCPP_HAS_NO_UNICODE
+ // range-fill and tuple-fill are identical
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_fill_align(_Iterator& __begin, _Iterator __end) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __begin != __end,
+ "when called with an empty input the function will cause "
+ "undefined behavior by evaluating data not in the input");
+ if (__begin + 1 != __end) {
+ if (__parse_alignment(*(__begin + 1))) {
+ __validate_fill_character(*__begin);
+
+ __fill_.__data[0] = *__begin;
+ __begin += 2;
+ return true;
+ }
+ }
+
+ if (!__parse_alignment(*__begin))
+ return false;
+
+ ++__begin;
+ return true;
+ }
+
+# endif // _LIBCPP_HAS_NO_UNICODE
+
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_sign(_Iterator& __begin) {
+ switch (*__begin) {
+ case _CharT('-'):
+ __sign_ = __sign::__minus;
+ break;
+ case _CharT('+'):
+ __sign_ = __sign::__plus;
+ break;
+ case _CharT(' '):
+ __sign_ = __sign::__space;
+ break;
+ default:
+ return false;
+ }
+ ++__begin;
+ return true;
+ }
+
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_alternate_form(_Iterator& __begin) {
+ if (*__begin != _CharT('#'))
+ return false;
+
+ __alternate_form_ = true;
+ ++__begin;
+ return true;
+ }
+
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_zero_padding(_Iterator& __begin) {
+ if (*__begin != _CharT('0'))
+ return false;
+
+ if (__alignment_ == __alignment::__default)
+ __alignment_ = __alignment::__zero_padding;
+ ++__begin;
+ return true;
+ }
+
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_width(_Iterator& __begin, _Iterator __end, auto& __ctx) {
+ if (*__begin == _CharT('0'))
+ std::__throw_format_error("The width option should not have a leading zero");
+
+ if (*__begin == _CharT('{')) {
+ __format::__parse_number_result __r = __format_spec::__parse_arg_id(++__begin, __end, __ctx);
+ __width_as_arg_ = true;
+ __width_ = __r.__value;
+ __begin = __r.__last;
+ return true;
+ }
+
+ if (*__begin < _CharT('0') || *__begin > _CharT('9'))
+ return false;
+
+ __format::__parse_number_result __r = __format::__parse_number(__begin, __end);
+ __width_ = __r.__value;
+ _LIBCPP_ASSERT_INTERNAL(__width_ != 0,
+ "A zero value isn't allowed and should be impossible, "
+ "due to validations in this function");
+ __begin = __r.__last;
+ return true;
+ }
+
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_precision(_Iterator& __begin, _Iterator __end, auto& __ctx) {
+ if (*__begin != _CharT('.'))
+ return false;
+
+ ++__begin;
+ if (__begin == __end)
+ std::__throw_format_error("End of input while parsing format specifier precision");
+
+ if (*__begin == _CharT('{')) {
+ __format::__parse_number_result __arg_id = __format_spec::__parse_arg_id(++__begin, __end, __ctx);
+ __precision_as_arg_ = true;
+ __precision_ = __arg_id.__value;
+ __begin = __arg_id.__last;
+ return true;
+ }
+
+ if (*__begin < _CharT('0') || *__begin > _CharT('9'))
+ std::__throw_format_error("The precision option does not contain a value or an argument index");
+
+ __format::__parse_number_result __r = __format::__parse_number(__begin, __end);
+ __precision_ = __r.__value;
+ __precision_as_arg_ = false;
+ __begin = __r.__last;
+ return true;
+ }
+
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_locale_specific_form(_Iterator& __begin) {
+ if (*__begin != _CharT('L'))
+ return false;
+
+ __locale_specific_form_ = true;
+ ++__begin;
+ return true;
+ }
+
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __parse_clear_brackets(_Iterator& __begin) {
+ if (*__begin != _CharT('n'))
+ return false;
+
+ __clear_brackets_ = true;
+ ++__begin;
+ return true;
+ }
+
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __parse_type(_Iterator& __begin) {
+ // Determines the type. It does not validate whether the selected type is
+ // valid. Most formatters have optional fields that are only allowed for
+ // certain types. These parsers need to do validation after the type has
+ // been parsed. So its easier to implement the validation for all types in
+ // the specific parse function.
+ switch (*__begin) {
+ case 'A':
+ __type_ = __type::__hexfloat_upper_case;
+ break;
+ case 'B':
+ __type_ = __type::__binary_upper_case;
+ break;
+ case 'E':
+ __type_ = __type::__scientific_upper_case;
+ break;
+ case 'F':
+ __type_ = __type::__fixed_upper_case;
+ break;
+ case 'G':
+ __type_ = __type::__general_upper_case;
+ break;
+ case 'X':
+ __type_ = __type::__hexadecimal_upper_case;
+ break;
+ case 'a':
+ __type_ = __type::__hexfloat_lower_case;
+ break;
+ case 'b':
+ __type_ = __type::__binary_lower_case;
+ break;
+ case 'c':
+ __type_ = __type::__char;
+ break;
+ case 'd':
+ __type_ = __type::__decimal;
+ break;
+ case 'e':
+ __type_ = __type::__scientific_lower_case;
+ break;
+ case 'f':
+ __type_ = __type::__fixed_lower_case;
+ break;
+ case 'g':
+ __type_ = __type::__general_lower_case;
+ break;
+ case 'o':
+ __type_ = __type::__octal;
+ break;
+ case 'p':
+ __type_ = __type::__pointer_lower_case;
+ break;
+ case 'P':
+ __type_ = __type::__pointer_upper_case;
+ break;
+ case 's':
+ __type_ = __type::__string;
+ break;
+ case 'x':
+ __type_ = __type::__hexadecimal_lower_case;
+ break;
+# if _LIBCPP_STD_VER >= 23
+ case '?':
+ __type_ = __type::__debug;
+ break;
+# endif
+ default:
+ return;
+ }
+ ++__begin;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int32_t __get_width(auto& __ctx) const {
+ if (!__width_as_arg_)
+ return __width_;
+
+ return __format_spec::__substitute_arg_id(__ctx.arg(__width_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int32_t __get_precision(auto& __ctx) const {
+ if (!__precision_as_arg_)
+ return __precision_;
+
+ return __format_spec::__substitute_arg_id(__ctx.arg(__precision_));
+ }
+};
+
+// Validates whether the reserved bitfields don't change the size.
+static_assert(sizeof(__parser<char>) == 16);
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+static_assert(sizeof(__parser<wchar_t>) == 16);
+# endif
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __process_display_type_string(__format_spec::__type __type) {
+ switch (__type) {
+ case __format_spec::__type::__default:
+ case __format_spec::__type::__string:
+ case __format_spec::__type::__debug:
+ break;
+
+ default:
+ std::__throw_format_error("The type option contains an invalid value for a string formatting argument");
+ }
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr void __process_display_type_bool_string(__parser<_CharT>& __parser, const char* __id) {
+ __parser.__validate(__format_spec::__fields_bool, __id);
+ if (__parser.__alignment_ == __alignment::__default)
+ __parser.__alignment_ = __alignment::__left;
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr void __process_display_type_char(__parser<_CharT>& __parser, const char* __id) {
+ __format_spec::__process_display_type_bool_string(__parser, __id);
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr void __process_parsed_bool(__parser<_CharT>& __parser, const char* __id) {
+ switch (__parser.__type_) {
+ case __format_spec::__type::__default:
+ case __format_spec::__type::__string:
+ __format_spec::__process_display_type_bool_string(__parser, __id);
+ break;
+
+ case __format_spec::__type::__binary_lower_case:
+ case __format_spec::__type::__binary_upper_case:
+ case __format_spec::__type::__octal:
+ case __format_spec::__type::__decimal:
+ case __format_spec::__type::__hexadecimal_lower_case:
+ case __format_spec::__type::__hexadecimal_upper_case:
+ break;
+
+ default:
+ __format_spec::__throw_invalid_type_format_error(__id);
+ }
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr void __process_parsed_char(__parser<_CharT>& __parser, const char* __id) {
+ switch (__parser.__type_) {
+ case __format_spec::__type::__default:
+ case __format_spec::__type::__char:
+ case __format_spec::__type::__debug:
+ __format_spec::__process_display_type_char(__parser, __id);
+ break;
+
+ case __format_spec::__type::__binary_lower_case:
+ case __format_spec::__type::__binary_upper_case:
+ case __format_spec::__type::__octal:
+ case __format_spec::__type::__decimal:
+ case __format_spec::__type::__hexadecimal_lower_case:
+ case __format_spec::__type::__hexadecimal_upper_case:
+ break;
+
+ default:
+ __format_spec::__throw_invalid_type_format_error(__id);
+ }
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr void __process_parsed_integer(__parser<_CharT>& __parser, const char* __id) {
+ switch (__parser.__type_) {
+ case __format_spec::__type::__default:
+ case __format_spec::__type::__binary_lower_case:
+ case __format_spec::__type::__binary_upper_case:
+ case __format_spec::__type::__octal:
+ case __format_spec::__type::__decimal:
+ case __format_spec::__type::__hexadecimal_lower_case:
+ case __format_spec::__type::__hexadecimal_upper_case:
+ break;
+
+ case __format_spec::__type::__char:
+ __format_spec::__process_display_type_char(__parser, __id);
+ break;
+
+ default:
+ __format_spec::__throw_invalid_type_format_error(__id);
+ }
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr void __process_parsed_floating_point(__parser<_CharT>& __parser, const char* __id) {
+ switch (__parser.__type_) {
+ case __format_spec::__type::__default:
+ case __format_spec::__type::__hexfloat_lower_case:
+ case __format_spec::__type::__hexfloat_upper_case:
+ // Precision specific behavior will be handled later.
+ break;
+ case __format_spec::__type::__scientific_lower_case:
+ case __format_spec::__type::__scientific_upper_case:
+ case __format_spec::__type::__fixed_lower_case:
+ case __format_spec::__type::__fixed_upper_case:
+ case __format_spec::__type::__general_lower_case:
+ case __format_spec::__type::__general_upper_case:
+ if (!__parser.__precision_as_arg_ && __parser.__precision_ == -1)
+ // Set the default precision for the call to to_chars.
+ __parser.__precision_ = 6;
+ break;
+
+ default:
+ __format_spec::__throw_invalid_type_format_error(__id);
+ }
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr void __process_display_type_pointer(__format_spec::__type __type, const char* __id) {
+ switch (__type) {
+ case __format_spec::__type::__default:
+ case __format_spec::__type::__pointer_lower_case:
+ case __format_spec::__type::__pointer_upper_case:
+ break;
+
+ default:
+ __format_spec::__throw_invalid_type_format_error(__id);
+ }
+}
+
+template <contiguous_iterator _Iterator>
+struct __column_width_result {
+ /// The number of output columns.
+ size_t __width_;
+ /// One beyond the last code unit used in the estimation.
+ ///
+ /// This limits the original output to fit in the wanted number of columns.
+ _Iterator __last_;
+};
+
+template <contiguous_iterator _Iterator>
+__column_width_result(size_t, _Iterator) -> __column_width_result<_Iterator>;
+
+/// Since a column width can be two it's possible that the requested column
+/// width can't be achieved. Depending on the intended usage the policy can be
+/// selected.
+/// - When used as precision the maximum width may not be exceeded and the
+/// result should be "rounded down" to the previous boundary.
+/// - When used as a width we're done once the minimum is reached, but
+/// exceeding is not an issue. Rounding down is an issue since that will
+/// result in writing fill characters. Therefore the result needs to be
+/// "rounded up".
+enum class __column_width_rounding { __down, __up };
+
+# ifndef _LIBCPP_HAS_NO_UNICODE
+
+namespace __detail {
+template <contiguous_iterator _Iterator>
+_LIBCPP_HIDE_FROM_ABI constexpr __column_width_result<_Iterator> __estimate_column_width_grapheme_clustering(
+ _Iterator __first, _Iterator __last, size_t __maximum, __column_width_rounding __rounding) noexcept {
+ using _CharT = iter_value_t<_Iterator>;
+ __unicode::__extended_grapheme_cluster_view<_CharT> __view{__first, __last};
+
+ __column_width_result<_Iterator> __result{0, __first};
+ while (__result.__last_ != __last && __result.__width_ <= __maximum) {
+ typename __unicode::__extended_grapheme_cluster_view<_CharT>::__cluster __cluster = __view.__consume();
+ int __width = __width_estimation_table::__estimated_width(__cluster.__code_point_);
+
+ // When the next entry would exceed the maximum width the previous width
+ // might be returned. For example when a width of 100 is requested the
+ // returned width might be 99, since the next code point has an estimated
+ // column width of 2. This depends on the rounding flag.
+ // When the maximum is exceeded the loop will abort the next iteration.
+ if (__rounding == __column_width_rounding::__down && __result.__width_ + __width > __maximum)
+ return __result;
+
+ __result.__width_ += __width;
+ __result.__last_ = __cluster.__last_;
+ }
+
+ return __result;
+}
+
+} // namespace __detail
+
+// Unicode can be stored in several formats: UTF-8, UTF-16, and UTF-32.
+// Depending on format the relation between the number of code units stored and
+// the number of output columns differs. The first relation is the number of
+// code units forming a code point. (The text assumes the code units are
+// unsigned.)
+// - UTF-8 The number of code units is between one and four. The first 127
+// Unicode code points match the ASCII character set. When the highest bit is
+// set it means the code point has more than one code unit.
+// - UTF-16: The number of code units is between 1 and 2. When the first
+// code unit is in the range [0xd800,0xdfff) it means the code point uses two
+// code units.
+// - UTF-32: The number of code units is always one.
+//
+// The code point to the number of columns is specified in
+// [format.string.std]/11. This list might change in the future.
+//
+// Another thing to be taken into account is Grapheme clustering. This means
+// that in some cases multiple code points are combined one element in the
+// output. For example:
+// - an ASCII character with a combined diacritical mark
+// - an emoji with a skin tone modifier
+// - a group of combined people emoji to create a family
+// - a combination of flag emoji
+//
+// See also:
+// - [format.string.general]/11
+// - https://en.wikipedia.org/wiki/UTF-8#Encoding
+// - https://en.wikipedia.org/wiki/UTF-16#U+D800_to_U+DFFF
+
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_ascii(char32_t __c) { return __c < 0x80; }
+
+/// Determines the number of output columns needed to render the input.
+///
+/// \note When the scanner encounters malformed Unicode it acts as-if every
+/// code unit is a one column code point. Typically a terminal uses the same
+/// strategy and replaces every malformed code unit with a one column
+/// replacement character.
+///
+/// \param __first Points to the first element of the input range.
+/// \param __last Points beyond the last element of the input range.
+/// \param __maximum The maximum number of output columns. The returned number
+/// of estimated output columns will not exceed this value.
+/// \param __rounding Selects the rounding method.
+/// \c __down result.__width_ <= __maximum
+/// \c __up result.__width_ <= __maximum + 1
+template <class _CharT, class _Iterator = typename basic_string_view<_CharT>::const_iterator>
+_LIBCPP_HIDE_FROM_ABI constexpr __column_width_result<_Iterator> __estimate_column_width(
+ basic_string_view<_CharT> __str, size_t __maximum, __column_width_rounding __rounding) noexcept {
+ // The width estimation is done in two steps:
+ // - Quickly process for the ASCII part. ASCII has the following properties
+ // - One code unit is one code point
+ // - Every code point has an estimated width of one
+ // - When needed it will a Unicode Grapheme clustering algorithm to find
+ // the proper place for truncation.
+
+ if (__str.empty() || __maximum == 0)
+ return {0, __str.begin()};
+
+ // ASCII has one caveat; when an ASCII character is followed by a non-ASCII
+ // character they might be part of an extended grapheme cluster. For example:
+ // an ASCII letter and a COMBINING ACUTE ACCENT
+ // The truncate should happen after the COMBINING ACUTE ACCENT. Therefore we
+ // need to scan one code unit beyond the requested precision. When this code
+ // unit is non-ASCII we omit the current code unit and let the Grapheme
+ // clustering algorithm do its work.
+ auto __it = __str.begin();
+ if (__format_spec::__is_ascii(*__it)) {
+ do {
+ --__maximum;
+ ++__it;
+ if (__it == __str.end())
+ return {__str.size(), __str.end()};
+
+ if (__maximum == 0) {
+ if (__format_spec::__is_ascii(*__it))
+ return {static_cast<size_t>(__it - __str.begin()), __it};
+
+ break;
+ }
+ } while (__format_spec::__is_ascii(*__it));
+ --__it;
+ ++__maximum;
+ }
+
+ ptrdiff_t __ascii_size = __it - __str.begin();
+ __column_width_result __result =
+ __detail::__estimate_column_width_grapheme_clustering(__it, __str.end(), __maximum, __rounding);
+
+ __result.__width_ += __ascii_size;
+ return __result;
+}
+# else // !defined(_LIBCPP_HAS_NO_UNICODE)
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI constexpr __column_width_result<typename basic_string_view<_CharT>::const_iterator>
+__estimate_column_width(basic_string_view<_CharT> __str, size_t __maximum, __column_width_rounding) noexcept {
+ // When Unicode isn't supported assume ASCII and every code unit is one code
+ // point. In ASCII the estimated column width is always one. Thus there's no
+ // need for rounding.
+ size_t __width = std::min(__str.size(), __maximum);
+ return {__width, __str.begin() + __width};
+}
+
+# endif // !defined(_LIBCPP_HAS_NO_UNICODE)
+
+} // namespace __format_spec
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_PARSER_STD_FORMAT_SPEC_H
diff --git a/libcxx/include/__cxx03/__format/range_default_formatter.h b/libcxx/include/__cxx03/__format/range_default_formatter.h
new file mode 100644
index 00000000000000..b35223ae933291
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/range_default_formatter.h
@@ -0,0 +1,214 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_RANGE_DEFAULT_FORMATTER_H
+#define _LIBCPP___FORMAT_RANGE_DEFAULT_FORMATTER_H
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#include <__algorithm/ranges_copy.h>
+#include <__chrono/statically_widen.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/formatter.h>
+#include <__format/range_formatter.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__ranges/concepts.h>
+#include <__ranges/data.h>
+#include <__ranges/from_range.h>
+#include <__ranges/size.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/pair.h>
+#include <string_view>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Rp, class _CharT>
+concept __const_formattable_range =
+ ranges::input_range<const _Rp> && formattable<ranges::range_reference_t<const _Rp>, _CharT>;
+
+template <class _Rp, class _CharT>
+using __fmt_maybe_const = conditional_t<__const_formattable_range<_Rp, _CharT>, const _Rp, _Rp>;
+
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wshadow")
+_LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wshadow")
+// This shadows map, set, and string.
+enum class range_format { disabled, map, set, sequence, string, debug_string };
+_LIBCPP_DIAGNOSTIC_POP
+
+// There is no definition of this struct, it's purely intended to be used to
+// generate diagnostics.
+template <class _Rp>
+struct _LIBCPP_TEMPLATE_VIS __instantiated_the_primary_template_of_format_kind;
+
+template <class _Rp>
+constexpr range_format format_kind = [] {
+ // [format.range.fmtkind]/1
+ // A program that instantiates the primary template of format_kind is ill-formed.
+ static_assert(sizeof(_Rp) != sizeof(_Rp), "create a template specialization of format_kind for your type");
+ return range_format::disabled;
+}();
+
+template <ranges::input_range _Rp>
+ requires same_as<_Rp, remove_cvref_t<_Rp>>
+inline constexpr range_format format_kind<_Rp> = [] {
+ // [format.range.fmtkind]/2
+
+ // 2.1 If same_as<remove_cvref_t<ranges::range_reference_t<R>>, R> is true,
+ // Otherwise format_kind<R> is range_format::disabled.
+ if constexpr (same_as<remove_cvref_t<ranges::range_reference_t<_Rp>>, _Rp>)
+ return range_format::disabled;
+ // 2.2 Otherwise, if the qualified-id R::key_type is valid and denotes a type:
+ else if constexpr (requires { typename _Rp::key_type; }) {
+ // 2.2.1 If the qualified-id R::mapped_type is valid and denotes a type ...
+ if constexpr (requires { typename _Rp::mapped_type; } &&
+ // 2.2.1 ... If either U is a specialization of pair or U is a specialization
+ // of tuple and tuple_size_v<U> == 2
+ __fmt_pair_like<remove_cvref_t<ranges::range_reference_t<_Rp>>>)
+ return range_format::map;
+ else
+ // 2.2.2 Otherwise format_kind<R> is range_format::set.
+ return range_format::set;
+ } else
+ // 2.3 Otherwise, format_kind<R> is range_format::sequence.
+ return range_format::sequence;
+}();
+
+template <range_format _Kp, ranges::input_range _Rp, class _CharT>
+struct _LIBCPP_TEMPLATE_VIS __range_default_formatter;
+
+// Required specializations
+
+template <ranges::input_range _Rp, class _CharT>
+struct _LIBCPP_TEMPLATE_VIS __range_default_formatter<range_format::sequence, _Rp, _CharT> {
+private:
+ using __maybe_const_r = __fmt_maybe_const<_Rp, _CharT>;
+ range_formatter<remove_cvref_t<ranges::range_reference_t<__maybe_const_r>>, _CharT> __underlying_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr void set_separator(basic_string_view<_CharT> __separator) noexcept {
+ __underlying_.set_separator(__separator);
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ set_brackets(basic_string_view<_CharT> __opening_bracket, basic_string_view<_CharT> __closing_bracket) noexcept {
+ __underlying_.set_brackets(__opening_bracket, __closing_bracket);
+ }
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return __underlying_.parse(__ctx);
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(__maybe_const_r& __range, _FormatContext& __ctx) const {
+ return __underlying_.format(__range, __ctx);
+ }
+};
+
+template <ranges::input_range _Rp, class _CharT>
+struct _LIBCPP_TEMPLATE_VIS __range_default_formatter<range_format::map, _Rp, _CharT> {
+private:
+ using __maybe_const_map = __fmt_maybe_const<_Rp, _CharT>;
+ using __element_type = remove_cvref_t<ranges::range_reference_t<__maybe_const_map>>;
+ range_formatter<__element_type, _CharT> __underlying_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr __range_default_formatter()
+ requires(__fmt_pair_like<__element_type>)
+ {
+ __underlying_.set_brackets(_LIBCPP_STATICALLY_WIDEN(_CharT, "{"), _LIBCPP_STATICALLY_WIDEN(_CharT, "}"));
+ __underlying_.underlying().set_brackets({}, {});
+ __underlying_.underlying().set_separator(_LIBCPP_STATICALLY_WIDEN(_CharT, ": "));
+ }
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return __underlying_.parse(__ctx);
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(__maybe_const_map& __range, _FormatContext& __ctx) const {
+ return __underlying_.format(__range, __ctx);
+ }
+};
+
+template <ranges::input_range _Rp, class _CharT>
+struct _LIBCPP_TEMPLATE_VIS __range_default_formatter<range_format::set, _Rp, _CharT> {
+private:
+ using __maybe_const_set = __fmt_maybe_const<_Rp, _CharT>;
+ using __element_type = remove_cvref_t<ranges::range_reference_t<__maybe_const_set>>;
+ range_formatter<__element_type, _CharT> __underlying_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr __range_default_formatter() {
+ __underlying_.set_brackets(_LIBCPP_STATICALLY_WIDEN(_CharT, "{"), _LIBCPP_STATICALLY_WIDEN(_CharT, "}"));
+ }
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return __underlying_.parse(__ctx);
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(__maybe_const_set& __range, _FormatContext& __ctx) const {
+ return __underlying_.format(__range, __ctx);
+ }
+};
+
+template <range_format _Kp, ranges::input_range _Rp, class _CharT>
+ requires(_Kp == range_format::string || _Kp == range_format::debug_string)
+struct _LIBCPP_TEMPLATE_VIS __range_default_formatter<_Kp, _Rp, _CharT> {
+private:
+ // This deviates from the Standard, there the exposition only type is
+ // formatter<basic_string<charT>, charT> underlying_;
+ // Using a string_view allows the format function to avoid a copy of the
+ // input range when it is a contigious range.
+ formatter<basic_string_view<_CharT>, _CharT> __underlying_;
+
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ typename _ParseContext::iterator __i = __underlying_.parse(__ctx);
+ if constexpr (_Kp == range_format::debug_string)
+ __underlying_.set_debug_format();
+ return __i;
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ format(conditional_t<ranges::input_range<const _Rp>, const _Rp&, _Rp&> __range, _FormatContext& __ctx) const {
+ // When the range is contiguous use a basic_string_view instead to avoid a
+ // copy of the underlying data. The basic_string_view formatter
+ // specialization is the "basic" string formatter in libc++.
+ if constexpr (ranges::contiguous_range<_Rp> && std::ranges::sized_range<_Rp>)
+ return __underlying_.format(basic_string_view<_CharT>{ranges::data(__range), ranges::size(__range)}, __ctx);
+ else
+ return __underlying_.format(basic_string<_CharT>{from_range, __range}, __ctx);
+ }
+};
+
+template <ranges::input_range _Rp, class _CharT>
+ requires(format_kind<_Rp> != range_format::disabled && formattable<ranges::range_reference_t<_Rp>, _CharT>)
+struct _LIBCPP_TEMPLATE_VIS formatter<_Rp, _CharT> : __range_default_formatter<format_kind<_Rp>, _Rp, _CharT> {};
+
+#endif //_LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_RANGE_DEFAULT_FORMATTER_H
diff --git a/libcxx/include/__cxx03/__format/range_formatter.h b/libcxx/include/__cxx03/__format/range_formatter.h
new file mode 100644
index 00000000000000..69156307434937
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/range_formatter.h
@@ -0,0 +1,264 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_RANGE_FORMATTER_H
+#define _LIBCPP___FORMAT_RANGE_FORMATTER_H
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#include <__algorithm/ranges_copy.h>
+#include <__chrono/statically_widen.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/buffer.h>
+#include <__format/concepts.h>
+#include <__format/format_context.h>
+#include <__format/format_error.h>
+#include <__format/formatter.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__ranges/concepts.h>
+#include <__ranges/data.h>
+#include <__ranges/from_range.h>
+#include <__ranges/size.h>
+#include <__type_traits/remove_cvref.h>
+#include <string_view>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Tp, class _CharT = char>
+ requires same_as<remove_cvref_t<_Tp>, _Tp> && formattable<_Tp, _CharT>
+struct _LIBCPP_TEMPLATE_VIS range_formatter {
+ _LIBCPP_HIDE_FROM_ABI constexpr void set_separator(basic_string_view<_CharT> __separator) noexcept {
+ __separator_ = __separator;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr void
+ set_brackets(basic_string_view<_CharT> __opening_bracket, basic_string_view<_CharT> __closing_bracket) noexcept {
+ __opening_bracket_ = __opening_bracket;
+ __closing_bracket_ = __closing_bracket;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr formatter<_Tp, _CharT>& underlying() noexcept { return __underlying_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const formatter<_Tp, _CharT>& underlying() const noexcept { return __underlying_; }
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ auto __begin = __parser_.__parse(__ctx, __format_spec::__fields_range);
+ auto __end = __ctx.end();
+ // Note the cases where __begin == __end in this code only happens when the
+ // replacement-field has no terminating }, or when the parse is manually
+ // called with a format-spec. The former is an error and the latter means
+ // using a formatter without the format functions or print.
+ if (__begin == __end) [[unlikely]]
+ return __parse_empty_range_underlying_spec(__ctx, __begin);
+
+ // The n field overrides a possible m type, therefore delay applying the
+ // effect of n until the type has been procesed.
+ __parse_type(__begin, __end);
+ if (__parser_.__clear_brackets_)
+ set_brackets({}, {});
+ if (__begin == __end) [[unlikely]]
+ return __parse_empty_range_underlying_spec(__ctx, __begin);
+
+ bool __has_range_underlying_spec = *__begin == _CharT(':');
+ if (__has_range_underlying_spec) {
+ // range-underlying-spec:
+ // : format-spec
+ ++__begin;
+ } else if (__begin != __end && *__begin != _CharT('}'))
+ // When there is no underlaying range the current parse should have
+ // consumed the format-spec. If not, the not consumed input will be
+ // processed by the underlying. For example {:-} for a range in invalid,
+ // the sign field is not present. Without this check the underlying_ will
+ // get -} as input which my be valid.
+ std::__throw_format_error("The format specifier should consume the input or end with a '}'");
+
+ __ctx.advance_to(__begin);
+ __begin = __underlying_.parse(__ctx);
+
+ // This test should not be required if __has_range_underlying_spec is false.
+ // However this test makes sure the underlying formatter left the parser in
+ // a valid state. (Note this is not a full protection against evil parsers.
+ // For example
+ // } this is test for the next argument {}
+ // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
+ // could consume more than it should.
+ if (__begin != __end && *__begin != _CharT('}'))
+ std::__throw_format_error("The format specifier should consume the input or end with a '}'");
+
+ if (__parser_.__type_ != __format_spec::__type::__default) {
+ // [format.range.formatter]/6
+ // If the range-type is s or ?s, then there shall be no n option and no
+ // range-underlying-spec.
+ if (__parser_.__clear_brackets_) {
+ if (__parser_.__type_ == __format_spec::__type::__string)
+ std::__throw_format_error("The n option and type s can't be used together");
+ std::__throw_format_error("The n option and type ?s can't be used together");
+ }
+ if (__has_range_underlying_spec) {
+ if (__parser_.__type_ == __format_spec::__type::__string)
+ std::__throw_format_error("Type s and an underlying format specification can't be used together");
+ std::__throw_format_error("Type ?s and an underlying format specification can't be used together");
+ }
+ } else if (!__has_range_underlying_spec)
+ std::__set_debug_format(__underlying_);
+
+ return __begin;
+ }
+
+ template <ranges::input_range _Rp, class _FormatContext>
+ requires formattable<ranges::range_reference_t<_Rp>, _CharT> &&
+ same_as<remove_cvref_t<ranges::range_reference_t<_Rp>>, _Tp>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(_Rp&& __range, _FormatContext& __ctx) const {
+ __format_spec::__parsed_specifications<_CharT> __specs = __parser_.__get_parsed_std_specifications(__ctx);
+
+ if (!__specs.__has_width())
+ return __format_range(__range, __ctx, __specs);
+
+ // The size of the buffer needed is:
+ // - open bracket characters
+ // - close bracket character
+ // - n elements where every element may have a different size
+ // - (n -1) separators
+ // The size of the element is hard to predict, knowing the type helps but
+ // it depends on the format-spec. As an initial estimate we guess 6
+ // characters.
+ // Typically both brackets are 1 character and the separator is 2
+ // characters. Which means there will be
+ // (n - 1) * 2 + 1 + 1 = n * 2 character
+ // So estimate 8 times the range size as buffer.
+ std::size_t __capacity_hint = 0;
+ if constexpr (std::ranges::sized_range<_Rp>)
+ __capacity_hint = 8 * ranges::size(__range);
+ __format::__retarget_buffer<_CharT> __buffer{__capacity_hint};
+ basic_format_context<typename __format::__retarget_buffer<_CharT>::__iterator, _CharT> __c{
+ __buffer.__make_output_iterator(), __ctx};
+
+ __format_range(__range, __c, __specs);
+
+ return __formatter::__write_string_no_precision(__buffer.__view(), __ctx.out(), __specs);
+ }
+
+ template <ranges::input_range _Rp, class _FormatContext>
+ typename _FormatContext::iterator _LIBCPP_HIDE_FROM_ABI
+ __format_range(_Rp&& __range, _FormatContext& __ctx, __format_spec::__parsed_specifications<_CharT> __specs) const {
+ if constexpr (same_as<_Tp, _CharT>) {
+ switch (__specs.__std_.__type_) {
+ case __format_spec::__type::__string:
+ case __format_spec::__type::__debug:
+ return __format_as_string(__range, __ctx, __specs.__std_.__type_ == __format_spec::__type::__debug);
+ default:
+ return __format_as_sequence(__range, __ctx);
+ }
+ } else
+ return __format_as_sequence(__range, __ctx);
+ }
+
+ template <ranges::input_range _Rp, class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ __format_as_string(_Rp&& __range, _FormatContext& __ctx, bool __debug_format) const {
+ // When the range is contiguous use a basic_string_view instead to avoid a
+ // copy of the underlying data. The basic_string_view formatter
+ // specialization is the "basic" string formatter in libc++.
+ if constexpr (ranges::contiguous_range<_Rp> && std::ranges::sized_range<_Rp>) {
+ std::formatter<basic_string_view<_CharT>, _CharT> __formatter;
+ if (__debug_format)
+ __formatter.set_debug_format();
+ return __formatter.format(
+ basic_string_view<_CharT>{
+ ranges::data(__range),
+ ranges::size(__range),
+ },
+ __ctx);
+ } else {
+ std::formatter<basic_string<_CharT>, _CharT> __formatter;
+ if (__debug_format)
+ __formatter.set_debug_format();
+ return __formatter.format(basic_string<_CharT>{from_range, __range}, __ctx);
+ }
+ }
+
+ template <ranges::input_range _Rp, class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator
+ __format_as_sequence(_Rp&& __range, _FormatContext& __ctx) const {
+ __ctx.advance_to(ranges::copy(__opening_bracket_, __ctx.out()).out);
+ bool __use_separator = false;
+ for (auto&& __e : __range) {
+ if (__use_separator)
+ __ctx.advance_to(ranges::copy(__separator_, __ctx.out()).out);
+ else
+ __use_separator = true;
+
+ __ctx.advance_to(__underlying_.format(__e, __ctx));
+ }
+
+ return ranges::copy(__closing_bracket_, __ctx.out()).out;
+ }
+
+ __format_spec::__parser<_CharT> __parser_{.__alignment_ = __format_spec::__alignment::__left};
+
+private:
+ template <contiguous_iterator _Iterator>
+ _LIBCPP_HIDE_FROM_ABI constexpr void __parse_type(_Iterator& __begin, _Iterator __end) {
+ switch (*__begin) {
+ case _CharT('m'):
+ if constexpr (__fmt_pair_like<_Tp>) {
+ set_brackets(_LIBCPP_STATICALLY_WIDEN(_CharT, "{"), _LIBCPP_STATICALLY_WIDEN(_CharT, "}"));
+ set_separator(_LIBCPP_STATICALLY_WIDEN(_CharT, ", "));
+ ++__begin;
+ } else
+ std::__throw_format_error("Type m requires a pair or a tuple with two elements");
+ break;
+
+ case _CharT('s'):
+ if constexpr (same_as<_Tp, _CharT>) {
+ __parser_.__type_ = __format_spec::__type::__string;
+ ++__begin;
+ } else
+ std::__throw_format_error("Type s requires character type as formatting argument");
+ break;
+
+ case _CharT('?'):
+ ++__begin;
+ if (__begin == __end || *__begin != _CharT('s'))
+ std::__throw_format_error("The format specifier should consume the input or end with a '}'");
+ if constexpr (same_as<_Tp, _CharT>) {
+ __parser_.__type_ = __format_spec::__type::__debug;
+ ++__begin;
+ } else
+ std::__throw_format_error("Type ?s requires character type as formatting argument");
+ }
+ }
+
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator
+ __parse_empty_range_underlying_spec(_ParseContext& __ctx, typename _ParseContext::iterator __begin) {
+ __ctx.advance_to(__begin);
+ [[maybe_unused]] typename _ParseContext::iterator __result = __underlying_.parse(__ctx);
+ _LIBCPP_ASSERT_INTERNAL(__result == __begin,
+ "the underlying's parse function should not advance the input beyond the end of the input");
+ return __begin;
+ }
+
+ formatter<_Tp, _CharT> __underlying_;
+ basic_string_view<_CharT> __separator_ = _LIBCPP_STATICALLY_WIDEN(_CharT, ", ");
+ basic_string_view<_CharT> __opening_bracket_ = _LIBCPP_STATICALLY_WIDEN(_CharT, "[");
+ basic_string_view<_CharT> __closing_bracket_ = _LIBCPP_STATICALLY_WIDEN(_CharT, "]");
+};
+
+#endif //_LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_RANGE_FORMATTER_H
diff --git a/libcxx/include/__cxx03/__format/unicode.h b/libcxx/include/__cxx03/__format/unicode.h
new file mode 100644
index 00000000000000..de7d0fea1df56a
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/unicode.h
@@ -0,0 +1,602 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_UNICODE_H
+#define _LIBCPP___FORMAT_UNICODE_H
+
+#include <__assert>
+#include <__bit/countl.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__format/extended_grapheme_cluster_table.h>
+#include <__format/indic_conjunct_break_table.h>
+#include <__iterator/concepts.h>
+#include <__iterator/readable_traits.h> // iter_value_t
+#include <__utility/unreachable.h>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __unicode {
+
+// Helper struct for the result of a consume operation.
+//
+// The status value for a correct code point is 0. This allows a valid value to
+// be used without masking.
+// When the decoding fails it know the number of code units affected. For the
+// current use-cases that value is not needed, therefore it is not stored.
+// The escape routine needs the number of code units for both a valid and
+// invalid character and keeps track of it itself. Doing it in this result
+// unconditionally would give some overhead when the value is unneeded.
+struct __consume_result {
+ // When __status == __ok it contains the decoded code point.
+ // Else it contains the replacement character U+FFFD
+ char32_t __code_point : 31;
+
+ enum : char32_t {
+ // Consumed a well-formed code point.
+ __ok = 0,
+ // Encountered invalid UTF-8
+ __error = 1
+ } __status : 1 {__ok};
+};
+static_assert(sizeof(__consume_result) == sizeof(char32_t));
+
+# ifndef _LIBCPP_HAS_NO_UNICODE
+
+/// Implements the grapheme cluster boundary rules
+///
+/// These rules are used to implement format's width estimation as stated in
+/// [format.string.std]/11
+///
+/// The Standard refers to UAX \#29 for Unicode 12.0.0
+/// https://www.unicode.org/reports/tr29/#Grapheme_Cluster_Boundary_Rules
+///
+/// The data tables used are
+/// https://www.unicode.org/Public/UCD/latest/ucd/auxiliary/GraphemeBreakProperty.txt
+/// https://www.unicode.org/Public/UCD/latest/ucd/emoji/emoji-data.txt
+/// https://www.unicode.org/Public/UCD/latest/ucd/auxiliary/GraphemeBreakTest.txt (for testing only)
+
+inline constexpr char32_t __replacement_character = U'\ufffd';
+
+// The error of a consume operation.
+//
+// This sets the code point to the replacement character. This code point does
+// not participate in the grapheme clustering, so grapheme clustering code can
+// ignore the error status and always use the code point.
+inline constexpr __consume_result __consume_result_error{__replacement_character, __consume_result::__error};
+
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool __is_high_surrogate(char32_t __value) {
+ return __value >= 0xd800 && __value <= 0xdbff;
+}
+
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool __is_low_surrogate(char32_t __value) {
+ return __value >= 0xdc00 && __value <= 0xdfff;
+}
+
+// https://www.unicode.org/glossary/#surrogate_code_point
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI inline constexpr bool __is_surrogate(char32_t __value) {
+ return __value >= 0xd800 && __value <= 0xdfff;
+}
+
+// https://www.unicode.org/glossary/#code_point
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI inline constexpr bool __is_code_point(char32_t __value) {
+ return __value <= 0x10ffff;
+}
+
+// https://www.unicode.org/glossary/#unicode_scalar_value
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI inline constexpr bool __is_scalar_value(char32_t __value) {
+ return __unicode::__is_code_point(__value) && !__unicode::__is_surrogate(__value);
+}
+
+template <contiguous_iterator _Iterator>
+ requires same_as<iter_value_t<_Iterator>, char>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_continuation(_Iterator __char, int __count) {
+ do {
+ if ((*__char & 0b1100'0000) != 0b1000'0000)
+ return false;
+ --__count;
+ ++__char;
+ } while (__count);
+ return true;
+}
+
+/// Helper class to extract a code unit from a Unicode character range.
+///
+/// The stored range is a view. There are multiple specialization for different
+/// character types.
+template <class _CharT>
+class __code_point_view;
+
+/// UTF-8 specialization.
+template <>
+class __code_point_view<char> {
+ using _Iterator = basic_string_view<char>::const_iterator;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __code_point_view(_Iterator __first, _Iterator __last)
+ : __first_(__first), __last_(__last) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __at_end() const noexcept { return __first_ == __last_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iterator __position() const noexcept { return __first_; }
+
+ // https://www.unicode.org/versions/latest/ch03.pdf#G7404
+ // Based on Table 3-7, Well-Formed UTF-8 Byte Sequences
+ //
+ // Code Points First Byte Second Byte Third Byte Fourth Byte Remarks
+ // U+0000..U+007F 00..7F U+0000..U+007F 1 code unit range
+ // C0..C1 80..BF invalid overlong encoding
+ // U+0080..U+07FF C2..DF 80..BF U+0080..U+07FF 2 code unit range
+ // E0 80..9F 80..BF invalid overlong encoding
+ // U+0800..U+0FFF E0 A0..BF 80..BF U+0800..U+FFFF 3 code unit range
+ // U+1000..U+CFFF E1..EC 80..BF 80..BF
+ // U+D000..U+D7FF ED 80..9F 80..BF
+ // U+D800..U+DFFF ED A0..BF 80..BF invalid encoding of surrogate code point
+ // U+E000..U+FFFF EE..EF 80..BF 80..BF
+ // F0 80..8F 80..BF 80..BF invalid overlong encoding
+ // U+10000..U+3FFFF F0 90..BF 80..BF 80..BF U+10000..U+10FFFF 4 code unit range
+ // U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF
+ // U+100000..U+10FFFF F4 80..8F 80..BF 80..BF
+ // F4 90..BF 80..BF 80..BF U+110000.. invalid code point range
+ //
+ // Unlike other parsers, these invalid entries are tested after decoding.
+ // - The parser always needs to consume these code units
+ // - The code is optimized for well-formed UTF-8
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __consume_result __consume() noexcept {
+ _LIBCPP_ASSERT_INTERNAL(__first_ != __last_, "can't move beyond the end of input");
+
+ // Based on the number of leading 1 bits the number of code units in the
+ // code point can be determined. See
+ // https://en.wikipedia.org/wiki/UTF-8#Encoding
+ switch (std::countl_one(static_cast<unsigned char>(*__first_))) {
+ case 0:
+ return {static_cast<unsigned char>(*__first_++)};
+
+ case 2: {
+ if (__last_ - __first_ < 2 || !__unicode::__is_continuation(__first_ + 1, 1)) [[unlikely]]
+ break;
+
+ char32_t __value = static_cast<unsigned char>(*__first_++) & 0x1f;
+ __value <<= 6;
+ __value |= static_cast<unsigned char>(*__first_++) & 0x3f;
+
+ // These values should be encoded in 1 UTF-8 code unit.
+ if (__value < 0x0080) [[unlikely]]
+ return __consume_result_error;
+
+ return {__value};
+ }
+
+ case 3: {
+ if (__last_ - __first_ < 3 || !__unicode::__is_continuation(__first_ + 1, 2)) [[unlikely]]
+ break;
+
+ char32_t __value = static_cast<unsigned char>(*__first_++) & 0x0f;
+ __value <<= 6;
+ __value |= static_cast<unsigned char>(*__first_++) & 0x3f;
+ __value <<= 6;
+ __value |= static_cast<unsigned char>(*__first_++) & 0x3f;
+
+ // These values should be encoded in 1 or 2 UTF-8 code units.
+ if (__value < 0x0800) [[unlikely]]
+ return __consume_result_error;
+
+ // A surrogate value is always encoded in 3 UTF-8 code units.
+ if (__unicode::__is_surrogate(__value)) [[unlikely]]
+ return __consume_result_error;
+
+ return {__value};
+ }
+
+ case 4: {
+ if (__last_ - __first_ < 4 || !__unicode::__is_continuation(__first_ + 1, 3)) [[unlikely]]
+ break;
+
+ char32_t __value = static_cast<unsigned char>(*__first_++) & 0x07;
+ __value <<= 6;
+ __value |= static_cast<unsigned char>(*__first_++) & 0x3f;
+ __value <<= 6;
+ __value |= static_cast<unsigned char>(*__first_++) & 0x3f;
+ __value <<= 6;
+ __value |= static_cast<unsigned char>(*__first_++) & 0x3f;
+
+ // These values should be encoded in 1, 2, or 3 UTF-8 code units.
+ if (__value < 0x10000) [[unlikely]]
+ return __consume_result_error;
+
+ // A value too large is always encoded in 4 UTF-8 code units.
+ if (!__unicode::__is_code_point(__value)) [[unlikely]]
+ return __consume_result_error;
+
+ return {__value};
+ }
+ }
+ // An invalid number of leading ones can be garbage or a code unit in the
+ // middle of a code point. By consuming one code unit the parser may get
+ // "in sync" after a few code units.
+ ++__first_;
+ return __consume_result_error;
+ }
+
+private:
+ _Iterator __first_;
+ _Iterator __last_;
+};
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_surrogate_pair_high(wchar_t __value) {
+ return __value >= 0xd800 && __value <= 0xdbff;
+}
+
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_surrogate_pair_low(wchar_t __value) {
+ return __value >= 0xdc00 && __value <= 0xdfff;
+}
+
+/// This specialization depends on the size of wchar_t
+/// - 2 UTF-16 (for example Windows and AIX)
+/// - 4 UTF-32 (for example Linux)
+template <>
+class __code_point_view<wchar_t> {
+ using _Iterator = typename basic_string_view<wchar_t>::const_iterator;
+
+public:
+ static_assert(sizeof(wchar_t) == 2 || sizeof(wchar_t) == 4, "sizeof(wchar_t) has a not implemented value");
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __code_point_view(_Iterator __first, _Iterator __last)
+ : __first_(__first), __last_(__last) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iterator __position() const noexcept { return __first_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __at_end() const noexcept { return __first_ == __last_; }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __consume_result __consume() noexcept {
+ _LIBCPP_ASSERT_INTERNAL(__first_ != __last_, "can't move beyond the end of input");
+
+ char32_t __value = static_cast<char32_t>(*__first_++);
+ if constexpr (sizeof(wchar_t) == 2) {
+ if (__unicode::__is_low_surrogate(__value)) [[unlikely]]
+ return __consume_result_error;
+
+ if (__unicode::__is_high_surrogate(__value)) {
+ if (__first_ == __last_ || !__unicode::__is_low_surrogate(static_cast<char32_t>(*__first_))) [[unlikely]]
+ return __consume_result_error;
+
+ __value -= 0xd800;
+ __value <<= 10;
+ __value += static_cast<char32_t>(*__first_++) - 0xdc00;
+ __value += 0x10000;
+
+ if (!__unicode::__is_code_point(__value)) [[unlikely]]
+ return __consume_result_error;
+ }
+ } else {
+ if (!__unicode::__is_scalar_value(__value)) [[unlikely]]
+ return __consume_result_error;
+ }
+
+ return {__value};
+ }
+
+private:
+ _Iterator __first_;
+ _Iterator __last_;
+};
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+// State machine to implement the Extended Grapheme Cluster Boundary
+//
+// The exact rules may change between Unicode versions.
+// This implements the extended rules see
+// https://www.unicode.org/reports/tr29/#Grapheme_Cluster_Boundaries
+class __extended_grapheme_cluster_break {
+ using __EGC_property = __extended_grapheme_custer_property_boundary::__property;
+ using __inCB_property = __indic_conjunct_break::__property;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __extended_grapheme_cluster_break(char32_t __first_code_point)
+ : __prev_code_point_(__first_code_point),
+ __prev_property_(__extended_grapheme_custer_property_boundary::__get_property(__first_code_point)) {
+ // Initializes the active rule.
+ if (__prev_property_ == __EGC_property::__Extended_Pictographic)
+ __active_rule_ = __rule::__GB11_emoji;
+ else if (__prev_property_ == __EGC_property::__Regional_Indicator)
+ __active_rule_ = __rule::__GB12_GB13_regional_indicator;
+ else if (__indic_conjunct_break::__get_property(__first_code_point) == __inCB_property::__Consonant)
+ __active_rule_ = __rule::__GB9c_indic_conjunct_break;
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(char32_t __next_code_point) {
+ __EGC_property __next_property = __extended_grapheme_custer_property_boundary::__get_property(__next_code_point);
+ bool __result = __evaluate(__next_code_point, __next_property);
+ __prev_code_point_ = __next_code_point;
+ __prev_property_ = __next_property;
+ return __result;
+ }
+
+ // The code point whose break propery are considered during the next
+ // evaluation cyle.
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr char32_t __current_code_point() const { return __prev_code_point_; }
+
+private:
+ // The naming of the identifiers matches the Unicode standard.
+ // NOLINTBEGIN(readability-identifier-naming)
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ __evaluate(char32_t __next_code_point, __EGC_property __next_property) {
+ switch (__active_rule_) {
+ case __rule::__none:
+ return __evaluate_none(__next_code_point, __next_property);
+ case __rule::__GB9c_indic_conjunct_break:
+ return __evaluate_GB9c_indic_conjunct_break(__next_code_point, __next_property);
+ case __rule::__GB11_emoji:
+ return __evaluate_GB11_emoji(__next_code_point, __next_property);
+ case __rule::__GB12_GB13_regional_indicator:
+ return __evaluate_GB12_GB13_regional_indicator(__next_code_point, __next_property);
+ }
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __evaluate_none(char32_t __next_code_point, __EGC_property __next_property) {
+ // *** Break at the start and end of text, unless the text is empty. ***
+
+ _LIBCPP_ASSERT_INTERNAL(__prev_property_ != __EGC_property::__sot, "should be handled in the constructor"); // GB1
+ _LIBCPP_ASSERT_INTERNAL(__prev_property_ != __EGC_property::__eot, "should be handled by our caller"); // GB2
+
+ // *** Do not break between a CR and LF. Otherwise, break before and after controls. ***
+ if (__prev_property_ == __EGC_property::__CR && __next_property == __EGC_property::__LF) // GB3
+ return false;
+
+ if (__prev_property_ == __EGC_property::__Control || __prev_property_ == __EGC_property::__CR ||
+ __prev_property_ == __EGC_property::__LF) // GB4
+ return true;
+
+ if (__next_property == __EGC_property::__Control || __next_property == __EGC_property::__CR ||
+ __next_property == __EGC_property::__LF) // GB5
+ return true;
+
+ // *** Do not break Hangul syllable sequences. ***
+ if (__prev_property_ == __EGC_property::__L &&
+ (__next_property == __EGC_property::__L || __next_property == __EGC_property::__V ||
+ __next_property == __EGC_property::__LV || __next_property == __EGC_property::__LVT)) // GB6
+ return false;
+
+ if ((__prev_property_ == __EGC_property::__LV || __prev_property_ == __EGC_property::__V) &&
+ (__next_property == __EGC_property::__V || __next_property == __EGC_property::__T)) // GB7
+ return false;
+
+ if ((__prev_property_ == __EGC_property::__LVT || __prev_property_ == __EGC_property::__T) &&
+ __next_property == __EGC_property::__T) // GB8
+ return false;
+
+ // *** Do not break before extending characters or ZWJ. ***
+ if (__next_property == __EGC_property::__Extend || __next_property == __EGC_property::__ZWJ)
+ return false; // GB9
+
+ // *** Do not break before SpacingMarks, or after Prepend characters. ***
+ if (__next_property == __EGC_property::__SpacingMark) // GB9a
+ return false;
+
+ if (__prev_property_ == __EGC_property::__Prepend) // GB9b
+ return false;
+
+ // *** Do not break within certain combinations with Indic_Conjunct_Break (InCB)=Linker. ***
+ if (__indic_conjunct_break::__get_property(__next_code_point) == __inCB_property::__Consonant) {
+ __active_rule_ = __rule::__GB9c_indic_conjunct_break;
+ __GB9c_indic_conjunct_break_state_ = __GB9c_indic_conjunct_break_state::__Consonant;
+ return true;
+ }
+
+ // *** Do not break within emoji modifier sequences or emoji zwj sequences. ***
+ if (__next_property == __EGC_property::__Extended_Pictographic) {
+ __active_rule_ = __rule::__GB11_emoji;
+ __GB11_emoji_state_ = __GB11_emoji_state::__Extended_Pictographic;
+ return true;
+ }
+
+ // *** Do not break within emoji flag sequences ***
+
+ // That is, do not break between regional indicator (RI) symbols if there
+ // is an odd number of RI characters before the break point.
+ if (__next_property == __EGC_property::__Regional_Indicator) { // GB12 + GB13
+ __active_rule_ = __rule::__GB12_GB13_regional_indicator;
+ return true;
+ }
+
+ // *** Otherwise, break everywhere. ***
+ return true; // GB999
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ __evaluate_GB9c_indic_conjunct_break(char32_t __next_code_point, __EGC_property __next_property) {
+ __inCB_property __break = __indic_conjunct_break::__get_property(__next_code_point);
+ if (__break == __inCB_property::__none) {
+ __active_rule_ = __rule::__none;
+ return __evaluate_none(__next_code_point, __next_property);
+ }
+
+ switch (__GB9c_indic_conjunct_break_state_) {
+ case __GB9c_indic_conjunct_break_state::__Consonant:
+ if (__break == __inCB_property::__Extend) {
+ return false;
+ }
+ if (__break == __inCB_property::__Linker) {
+ __GB9c_indic_conjunct_break_state_ = __GB9c_indic_conjunct_break_state::__Linker;
+ return false;
+ }
+ __active_rule_ = __rule::__none;
+ return __evaluate_none(__next_code_point, __next_property);
+
+ case __GB9c_indic_conjunct_break_state::__Linker:
+ if (__break == __inCB_property::__Extend) {
+ return false;
+ }
+ if (__break == __inCB_property::__Linker) {
+ return false;
+ }
+ if (__break == __inCB_property::__Consonant) {
+ __GB9c_indic_conjunct_break_state_ = __GB9c_indic_conjunct_break_state::__Consonant;
+ return false;
+ }
+ __active_rule_ = __rule::__none;
+ return __evaluate_none(__next_code_point, __next_property);
+ }
+ __libcpp_unreachable();
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ __evaluate_GB11_emoji(char32_t __next_code_point, __EGC_property __next_property) {
+ switch (__GB11_emoji_state_) {
+ case __GB11_emoji_state::__Extended_Pictographic:
+ if (__next_property == __EGC_property::__Extend) {
+ __GB11_emoji_state_ = __GB11_emoji_state::__Extend;
+ return false;
+ }
+ [[fallthrough]];
+ case __GB11_emoji_state::__Extend:
+ if (__next_property == __EGC_property::__ZWJ) {
+ __GB11_emoji_state_ = __GB11_emoji_state::__ZWJ;
+ return false;
+ }
+ if (__next_property == __EGC_property::__Extend)
+ return false;
+ __active_rule_ = __rule::__none;
+ return __evaluate_none(__next_code_point, __next_property);
+
+ case __GB11_emoji_state::__ZWJ:
+ if (__next_property == __EGC_property::__Extended_Pictographic) {
+ __GB11_emoji_state_ = __GB11_emoji_state::__Extended_Pictographic;
+ return false;
+ }
+ __active_rule_ = __rule::__none;
+ return __evaluate_none(__next_code_point, __next_property);
+ }
+ __libcpp_unreachable();
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool
+ __evaluate_GB12_GB13_regional_indicator(char32_t __next_code_point, __EGC_property __next_property) {
+ __active_rule_ = __rule::__none;
+ if (__next_property == __EGC_property::__Regional_Indicator)
+ return false;
+ return __evaluate_none(__next_code_point, __next_property);
+ }
+
+ char32_t __prev_code_point_;
+ __EGC_property __prev_property_;
+
+ enum class __rule {
+ __none,
+ __GB9c_indic_conjunct_break,
+ __GB11_emoji,
+ __GB12_GB13_regional_indicator,
+ };
+ __rule __active_rule_ = __rule::__none;
+
+ enum class __GB11_emoji_state {
+ __Extended_Pictographic,
+ __Extend,
+ __ZWJ,
+ };
+ __GB11_emoji_state __GB11_emoji_state_ = __GB11_emoji_state::__Extended_Pictographic;
+
+ enum class __GB9c_indic_conjunct_break_state {
+ __Consonant,
+ __Linker,
+ };
+
+ __GB9c_indic_conjunct_break_state __GB9c_indic_conjunct_break_state_ = __GB9c_indic_conjunct_break_state::__Consonant;
+
+ // NOLINTEND(readability-identifier-naming)
+};
+
+/// Helper class to extract an extended grapheme cluster from a Unicode character range.
+///
+/// This function is used to determine the column width of an extended grapheme
+/// cluster. In order to do that only the first code point is evaluated.
+/// Therefore only this code point is extracted.
+template <class _CharT>
+class __extended_grapheme_cluster_view {
+ using _Iterator = typename basic_string_view<_CharT>::const_iterator;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __extended_grapheme_cluster_view(_Iterator __first, _Iterator __last)
+ : __code_point_view_(__first, __last), __at_break_(__code_point_view_.__consume().__code_point) {}
+
+ struct __cluster {
+ /// The first code point of the extended grapheme cluster.
+ ///
+ /// The first code point is used to estimate the width of the extended
+ /// grapheme cluster.
+ char32_t __code_point_;
+
+ /// Points one beyond the last code unit in the extended grapheme cluster.
+ ///
+ /// It's expected the caller has the start position and thus can determine
+ /// the code unit range of the extended grapheme cluster.
+ _Iterator __last_;
+ };
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __cluster __consume() {
+ char32_t __code_point = __at_break_.__current_code_point();
+ _Iterator __position = __code_point_view_.__position();
+ while (!__code_point_view_.__at_end()) {
+ if (__at_break_(__code_point_view_.__consume().__code_point))
+ break;
+ __position = __code_point_view_.__position();
+ }
+ return {__code_point, __position};
+ }
+
+private:
+ __code_point_view<_CharT> __code_point_view_;
+ __extended_grapheme_cluster_break __at_break_;
+};
+
+template <contiguous_iterator _Iterator>
+__extended_grapheme_cluster_view(_Iterator, _Iterator) -> __extended_grapheme_cluster_view<iter_value_t<_Iterator>>;
+
+# else // _LIBCPP_HAS_NO_UNICODE
+
+// For ASCII every character is a "code point".
+// This makes it easier to write code agnostic of the _LIBCPP_HAS_NO_UNICODE define.
+template <class _CharT>
+class __code_point_view {
+ using _Iterator = typename basic_string_view<_CharT>::const_iterator;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __code_point_view(_Iterator __first, _Iterator __last)
+ : __first_(__first), __last_(__last) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __at_end() const noexcept { return __first_ == __last_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iterator __position() const noexcept { return __first_; }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __consume_result __consume() noexcept {
+ _LIBCPP_ASSERT_INTERNAL(__first_ != __last_, "can't move beyond the end of input");
+ return {static_cast<char32_t>(*__first_++)};
+ }
+
+private:
+ _Iterator __first_;
+ _Iterator __last_;
+};
+
+# endif // _LIBCPP_HAS_NO_UNICODE
+
+} // namespace __unicode
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_UNICODE_H
diff --git a/libcxx/include/__cxx03/__format/width_estimation_table.h b/libcxx/include/__cxx03/__format/width_estimation_table.h
new file mode 100644
index 00000000000000..11f61dea18d696
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/width_estimation_table.h
@@ -0,0 +1,270 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// WARNING, this entire header is generated by
+// utils/generate_width_estimation_table.py
+// DO NOT MODIFY!
+
+// UNICODE, INC. LICENSE AGREEMENT - DATA FILES AND SOFTWARE
+//
+// See Terms of Use <https://www.unicode.org/copyright.html>
+// for definitions of Unicode Inc.'s Data Files and Software.
+//
+// NOTICE TO USER: Carefully read the following legal agreement.
+// BY DOWNLOADING, INSTALLING, COPYING OR OTHERWISE USING UNICODE INC.'S
+// DATA FILES ("DATA FILES"), AND/OR SOFTWARE ("SOFTWARE"),
+// YOU UNEQUIVOCALLY ACCEPT, AND AGREE TO BE BOUND BY, ALL OF THE
+// TERMS AND CONDITIONS OF THIS AGREEMENT.
+// IF YOU DO NOT AGREE, DO NOT DOWNLOAD, INSTALL, COPY, DISTRIBUTE OR USE
+// THE DATA FILES OR SOFTWARE.
+//
+// COPYRIGHT AND PERMISSION NOTICE
+//
+// Copyright (c) 1991-2022 Unicode, Inc. All rights reserved.
+// Distributed under the Terms of Use in https://www.unicode.org/copyright.html.
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of the Unicode data files and any associated documentation
+// (the "Data Files") or Unicode software and any associated documentation
+// (the "Software") to deal in the Data Files or Software
+// without restriction, including without limitation the rights to use,
+// copy, modify, merge, publish, distribute, and/or sell copies of
+// the Data Files or Software, and to permit persons to whom the Data Files
+// or Software are furnished to do so, provided that either
+// (a) this copyright and permission notice appear with all copies
+// of the Data Files or Software, or
+// (b) this copyright and permission notice appear in associated
+// Documentation.
+//
+// THE DATA FILES AND SOFTWARE ARE PROVIDED "AS IS", WITHOUT WARRANTY OF
+// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+// WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+// IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS
+// NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL
+// DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+// DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THE DATA FILES OR SOFTWARE.
+//
+// Except as contained in this notice, the name of a copyright holder
+// shall not be used in advertising or otherwise to promote the sale,
+// use or other dealings in these Data Files or Software without prior
+// written authorization of the copyright holder.
+
+#ifndef _LIBCPP___FORMAT_WIDTH_ESTIMATION_TABLE_H
+#define _LIBCPP___FORMAT_WIDTH_ESTIMATION_TABLE_H
+
+#include <__algorithm/ranges_upper_bound.h>
+#include <__config>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace __width_estimation_table {
+
+/// The entries of the characters with an estimated width of 2.
+///
+/// Contains the entries for [format.string.std]/12
+/// - Any code point with the East_Asian_Width="W" or East_Asian_Width="F"
+/// Derived Extracted Property as described by UAX #44
+/// - U+4DC0 - U+4DFF (Yijing Hexagram Symbols)
+/// - U+1F300 - U+1F5FF (Miscellaneous Symbols and Pictographs)
+/// - U+1F900 - U+1F9FF (Supplemental Symbols and Pictographs)
+///
+/// The data is generated from
+/// - https://www.unicode.org/Public/UCD/latest/ucd/EastAsianWidth.txt
+/// - The "overrides" in [format.string.std]/12
+///
+/// The format of EastAsianWidth.txt is two fields separated by a semicolon.
+/// Field 0: Unicode code point value or range of code point values
+/// Field 1: East_Asian_Width property, consisting of one of the following values:
+/// "A", "F", "H", "N", "Na", "W"
+/// - All code points, assigned or unassigned, that are not listed
+/// explicitly are given the value "N".
+/// - The unassigned code points in the following blocks default to "W":
+/// CJK Unified Ideographs Extension A: U+3400..U+4DBF
+/// CJK Unified Ideographs: U+4E00..U+9FFF
+/// CJK Compatibility Ideographs: U+F900..U+FAFF
+/// - All undesignated code points in Planes 2 and 3, whether inside or
+/// outside of allocated blocks, default to "W":
+/// Plane 2: U+20000..U+2FFFD
+/// Plane 3: U+30000..U+3FFFD
+///
+/// The table is similar to the table
+/// __extended_grapheme_custer_property_boundary::__entries
+/// which explains the details of these classes. The only difference is this
+/// table lacks a property, thus having more bits available for the size.
+///
+/// The maximum code point that has an estimated width of 2 is U+3FFFD. This
+/// value can be encoded in 18 bits. Thus the upper 3 bits of the code point
+/// are always 0. These 3 bits are used to enlarge the offset range. This
+/// optimization reduces the table in Unicode 15 from 184 to 104 entries,
+/// saving 320 bytes.
+///
+/// The data has 2 values:
+/// - bits [0, 13] The size of the range, allowing 16384 elements.
+/// - bits [14, 31] The lower bound code point of the range. The upper bound of
+/// the range is lower bound + size.
+_LIBCPP_HIDE_FROM_ABI inline constexpr uint32_t __entries[107] = {
+ 0x0440005f /* 00001100 - 0000115f [ 96] */, //
+ 0x08c68001 /* 0000231a - 0000231b [ 2] */, //
+ 0x08ca4001 /* 00002329 - 0000232a [ 2] */, //
+ 0x08fa4003 /* 000023e9 - 000023ec [ 4] */, //
+ 0x08fc0000 /* 000023f0 - 000023f0 [ 1] */, //
+ 0x08fcc000 /* 000023f3 - 000023f3 [ 1] */, //
+ 0x097f4001 /* 000025fd - 000025fe [ 2] */, //
+ 0x09850001 /* 00002614 - 00002615 [ 2] */, //
+ 0x0992000b /* 00002648 - 00002653 [ 12] */, //
+ 0x099fc000 /* 0000267f - 0000267f [ 1] */, //
+ 0x09a4c000 /* 00002693 - 00002693 [ 1] */, //
+ 0x09a84000 /* 000026a1 - 000026a1 [ 1] */, //
+ 0x09aa8001 /* 000026aa - 000026ab [ 2] */, //
+ 0x09af4001 /* 000026bd - 000026be [ 2] */, //
+ 0x09b10001 /* 000026c4 - 000026c5 [ 2] */, //
+ 0x09b38000 /* 000026ce - 000026ce [ 1] */, //
+ 0x09b50000 /* 000026d4 - 000026d4 [ 1] */, //
+ 0x09ba8000 /* 000026ea - 000026ea [ 1] */, //
+ 0x09bc8001 /* 000026f2 - 000026f3 [ 2] */, //
+ 0x09bd4000 /* 000026f5 - 000026f5 [ 1] */, //
+ 0x09be8000 /* 000026fa - 000026fa [ 1] */, //
+ 0x09bf4000 /* 000026fd - 000026fd [ 1] */, //
+ 0x09c14000 /* 00002705 - 00002705 [ 1] */, //
+ 0x09c28001 /* 0000270a - 0000270b [ 2] */, //
+ 0x09ca0000 /* 00002728 - 00002728 [ 1] */, //
+ 0x09d30000 /* 0000274c - 0000274c [ 1] */, //
+ 0x09d38000 /* 0000274e - 0000274e [ 1] */, //
+ 0x09d4c002 /* 00002753 - 00002755 [ 3] */, //
+ 0x09d5c000 /* 00002757 - 00002757 [ 1] */, //
+ 0x09e54002 /* 00002795 - 00002797 [ 3] */, //
+ 0x09ec0000 /* 000027b0 - 000027b0 [ 1] */, //
+ 0x09efc000 /* 000027bf - 000027bf [ 1] */, //
+ 0x0ac6c001 /* 00002b1b - 00002b1c [ 2] */, //
+ 0x0ad40000 /* 00002b50 - 00002b50 [ 1] */, //
+ 0x0ad54000 /* 00002b55 - 00002b55 [ 1] */, //
+ 0x0ba00019 /* 00002e80 - 00002e99 [ 26] */, //
+ 0x0ba6c058 /* 00002e9b - 00002ef3 [ 89] */, //
+ 0x0bc000d5 /* 00002f00 - 00002fd5 [ 214] */, //
+ 0x0bfc004e /* 00002ff0 - 0000303e [ 79] */, //
+ 0x0c104055 /* 00003041 - 00003096 [ 86] */, //
+ 0x0c264066 /* 00003099 - 000030ff [ 103] */, //
+ 0x0c41402a /* 00003105 - 0000312f [ 43] */, //
+ 0x0c4c405d /* 00003131 - 0000318e [ 94] */, //
+ 0x0c640053 /* 00003190 - 000031e3 [ 84] */, //
+ 0x0c7bc02f /* 000031ef - 0000321e [ 48] */, //
+ 0x0c880027 /* 00003220 - 00003247 [ 40] */, //
+ 0x0c943fff /* 00003250 - 0000724f [16384] */, //
+ 0x1c94323c /* 00007250 - 0000a48c [12861] */, //
+ 0x29240036 /* 0000a490 - 0000a4c6 [ 55] */, //
+ 0x2a58001c /* 0000a960 - 0000a97c [ 29] */, //
+ 0x2b002ba3 /* 0000ac00 - 0000d7a3 [11172] */, //
+ 0x3e4001ff /* 0000f900 - 0000faff [ 512] */, //
+ 0x3f840009 /* 0000fe10 - 0000fe19 [ 10] */, //
+ 0x3f8c0022 /* 0000fe30 - 0000fe52 [ 35] */, //
+ 0x3f950012 /* 0000fe54 - 0000fe66 [ 19] */, //
+ 0x3f9a0003 /* 0000fe68 - 0000fe6b [ 4] */, //
+ 0x3fc0405f /* 0000ff01 - 0000ff60 [ 96] */, //
+ 0x3ff80006 /* 0000ffe0 - 0000ffe6 [ 7] */, //
+ 0x5bf80004 /* 00016fe0 - 00016fe4 [ 5] */, //
+ 0x5bfc0001 /* 00016ff0 - 00016ff1 [ 2] */, //
+ 0x5c0017f7 /* 00017000 - 000187f7 [ 6136] */, //
+ 0x620004d5 /* 00018800 - 00018cd5 [ 1238] */, //
+ 0x63400008 /* 00018d00 - 00018d08 [ 9] */, //
+ 0x6bfc0003 /* 0001aff0 - 0001aff3 [ 4] */, //
+ 0x6bfd4006 /* 0001aff5 - 0001affb [ 7] */, //
+ 0x6bff4001 /* 0001affd - 0001affe [ 2] */, //
+ 0x6c000122 /* 0001b000 - 0001b122 [ 291] */, //
+ 0x6c4c8000 /* 0001b132 - 0001b132 [ 1] */, //
+ 0x6c540002 /* 0001b150 - 0001b152 [ 3] */, //
+ 0x6c554000 /* 0001b155 - 0001b155 [ 1] */, //
+ 0x6c590003 /* 0001b164 - 0001b167 [ 4] */, //
+ 0x6c5c018b /* 0001b170 - 0001b2fb [ 396] */, //
+ 0x7c010000 /* 0001f004 - 0001f004 [ 1] */, //
+ 0x7c33c000 /* 0001f0cf - 0001f0cf [ 1] */, //
+ 0x7c638000 /* 0001f18e - 0001f18e [ 1] */, //
+ 0x7c644009 /* 0001f191 - 0001f19a [ 10] */, //
+ 0x7c800002 /* 0001f200 - 0001f202 [ 3] */, //
+ 0x7c84002b /* 0001f210 - 0001f23b [ 44] */, //
+ 0x7c900008 /* 0001f240 - 0001f248 [ 9] */, //
+ 0x7c940001 /* 0001f250 - 0001f251 [ 2] */, //
+ 0x7c980005 /* 0001f260 - 0001f265 [ 6] */, //
+ 0x7cc0034f /* 0001f300 - 0001f64f [ 848] */, //
+ 0x7da00045 /* 0001f680 - 0001f6c5 [ 70] */, //
+ 0x7db30000 /* 0001f6cc - 0001f6cc [ 1] */, //
+ 0x7db40002 /* 0001f6d0 - 0001f6d2 [ 3] */, //
+ 0x7db54002 /* 0001f6d5 - 0001f6d7 [ 3] */, //
+ 0x7db70003 /* 0001f6dc - 0001f6df [ 4] */, //
+ 0x7dbac001 /* 0001f6eb - 0001f6ec [ 2] */, //
+ 0x7dbd0008 /* 0001f6f4 - 0001f6fc [ 9] */, //
+ 0x7df8000b /* 0001f7e0 - 0001f7eb [ 12] */, //
+ 0x7dfc0000 /* 0001f7f0 - 0001f7f0 [ 1] */, //
+ 0x7e4000ff /* 0001f900 - 0001f9ff [ 256] */, //
+ 0x7e9c000c /* 0001fa70 - 0001fa7c [ 13] */, //
+ 0x7ea00008 /* 0001fa80 - 0001fa88 [ 9] */, //
+ 0x7ea4002d /* 0001fa90 - 0001fabd [ 46] */, //
+ 0x7eafc006 /* 0001fabf - 0001fac5 [ 7] */, //
+ 0x7eb3800d /* 0001face - 0001fadb [ 14] */, //
+ 0x7eb80008 /* 0001fae0 - 0001fae8 [ 9] */, //
+ 0x7ebc0008 /* 0001faf0 - 0001faf8 [ 9] */, //
+ 0x80003fff /* 00020000 - 00023fff [16384] */, //
+ 0x90003fff /* 00024000 - 00027fff [16384] */, //
+ 0xa0003fff /* 00028000 - 0002bfff [16384] */, //
+ 0xb0003ffd /* 0002c000 - 0002fffd [16382] */, //
+ 0xc0003fff /* 00030000 - 00033fff [16384] */, //
+ 0xd0003fff /* 00034000 - 00037fff [16384] */, //
+ 0xe0003fff /* 00038000 - 0003bfff [16384] */, //
+ 0xf0003ffd /* 0003c000 - 0003fffd [16382] */};
+
+/// The upper bound entry of EastAsianWidth.txt.
+///
+/// Values greater than this value may have more than 18 significant bits.
+/// They always have a width of 1. This property makes it possible to store
+/// the table in its compact form.
+inline constexpr uint32_t __table_upper_bound = 0x0003fffd;
+
+/// Returns the estimated width of a Unicode code point.
+///
+/// \\pre The code point is a valid Unicode code point.
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int __estimated_width(const char32_t __code_point) noexcept {
+ // Since __table_upper_bound contains the unshifted range do the
+ // comparison without shifting.
+ if (__code_point > __table_upper_bound) [[unlikely]]
+ return 1;
+
+ // When the code-point is less than the first element in the table
+ // the lookup is quite expensive. Since quite some scripts are in
+ // that range, it makes sense to validate that first.
+ // The std_format_spec_string_unicode benchmark gives a measurable
+ // improvement.
+ if (__code_point < (__entries[0] >> 14))
+ return 1;
+
+ ptrdiff_t __i = std::ranges::upper_bound(__entries, (__code_point << 14) | 0x3fffu) - __entries;
+ if (__i == 0)
+ return 1;
+
+ --__i;
+ uint32_t __upper_bound = (__entries[__i] >> 14) + (__entries[__i] & 0x3fffu);
+ return 1 + (__code_point <= __upper_bound);
+}
+
+} // namespace __width_estimation_table
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FORMAT_WIDTH_ESTIMATION_TABLE_H
diff --git a/libcxx/include/__cxx03/__format/write_escaped.h b/libcxx/include/__cxx03/__format/write_escaped.h
new file mode 100644
index 00000000000000..052ea98c3c3b8c
--- /dev/null
+++ b/libcxx/include/__cxx03/__format/write_escaped.h
@@ -0,0 +1,242 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FORMAT_WRITE_ESCAPED_H
+#define _LIBCPP___FORMAT_WRITE_ESCAPED_H
+
+#include <__algorithm/ranges_copy.h>
+#include <__algorithm/ranges_for_each.h>
+#include <__charconv/to_chars_integral.h>
+#include <__charconv/to_chars_result.h>
+#include <__chrono/statically_widen.h>
+#include <__format/escaped_output_table.h>
+#include <__format/formatter_output.h>
+#include <__format/parser_std_format_spec.h>
+#include <__format/unicode.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__memory/addressof.h>
+#include <__system_error/errc.h>
+#include <__type_traits/make_unsigned.h>
+#include <__utility/move.h>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __formatter {
+
+#if _LIBCPP_STD_VER >= 20
+
+/// Writes a string using format's width estimation algorithm.
+///
+/// \note When \c _LIBCPP_HAS_NO_UNICODE is defined the function assumes the
+/// input is ASCII.
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__write_string(basic_string_view<_CharT> __str,
+ output_iterator<const _CharT&> auto __out_it,
+ __format_spec::__parsed_specifications<_CharT> __specs) -> decltype(__out_it) {
+ if (!__specs.__has_precision())
+ return __formatter::__write_string_no_precision(__str, std::move(__out_it), __specs);
+
+ int __size = __formatter::__truncate(__str, __specs.__precision_);
+
+ return __formatter::__write(__str.begin(), __str.end(), std::move(__out_it), __specs, __size);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+#if _LIBCPP_STD_VER >= 23
+
+struct __nul_terminator {};
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const _CharT* __cstr, __nul_terminator) {
+ return *__cstr == _CharT('\0');
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI void
+__write_escaped_code_unit(basic_string<_CharT>& __str, char32_t __value, const _CharT* __prefix) {
+ back_insert_iterator __out_it{__str};
+ std::ranges::copy(__prefix, __nul_terminator{}, __out_it);
+
+ char __buffer[8];
+ to_chars_result __r = std::to_chars(std::begin(__buffer), std::end(__buffer), __value, 16);
+ _LIBCPP_ASSERT_INTERNAL(__r.ec == errc(0), "Internal buffer too small");
+ std::ranges::copy(std::begin(__buffer), __r.ptr, __out_it);
+
+ __str += _CharT('}');
+}
+
+// [format.string.escaped]/2.2.1.2
+// ...
+// then the sequence \u{hex-digit-sequence} is appended to E, where
+// hex-digit-sequence is the shortest hexadecimal representation of C using
+// lower-case hexadecimal digits.
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI void __write_well_formed_escaped_code_unit(basic_string<_CharT>& __str, char32_t __value) {
+ __formatter::__write_escaped_code_unit(__str, __value, _LIBCPP_STATICALLY_WIDEN(_CharT, "\\u{"));
+}
+
+// [format.string.escaped]/2.2.3
+// Otherwise (X is a sequence of ill-formed code units), each code unit U is
+// appended to E in order as the sequence \x{hex-digit-sequence}, where
+// hex-digit-sequence is the shortest hexadecimal representation of U using
+// lower-case hexadecimal digits.
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI void __write_escape_ill_formed_code_unit(basic_string<_CharT>& __str, char32_t __value) {
+ __formatter::__write_escaped_code_unit(__str, __value, _LIBCPP_STATICALLY_WIDEN(_CharT, "\\x{"));
+}
+
+template <class _CharT>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool
+__is_escaped_sequence_written(basic_string<_CharT>& __str, bool __last_escaped, char32_t __value) {
+# ifdef _LIBCPP_HAS_NO_UNICODE
+ // For ASCII assume everything above 127 is printable.
+ if (__value > 127)
+ return false;
+# endif
+
+ // [format.string.escaped]/2.2.1.2.1
+ // CE is UTF-8, UTF-16, or UTF-32 and C corresponds to a Unicode scalar
+ // value whose Unicode property General_Category has a value in the groups
+ // Separator (Z) or Other (C), as described by UAX #44 of the Unicode Standard,
+ if (!__escaped_output_table::__needs_escape(__value))
+ // [format.string.escaped]/2.2.1.2.2
+ // CE is UTF-8, UTF-16, or UTF-32 and C corresponds to a Unicode scalar
+ // value with the Unicode property Grapheme_Extend=Yes as described by UAX
+ // #44 of the Unicode Standard and C is not immediately preceded in S by a
+ // character P appended to E without translation to an escape sequence,
+ if (!__last_escaped || __extended_grapheme_custer_property_boundary::__get_property(__value) !=
+ __extended_grapheme_custer_property_boundary::__property::__Extend)
+ return false;
+
+ __formatter::__write_well_formed_escaped_code_unit(__str, __value);
+ return true;
+}
+
+template <class _CharT>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr char32_t __to_char32(_CharT __value) {
+ return static_cast<make_unsigned_t<_CharT>>(__value);
+}
+
+enum class __escape_quotation_mark { __apostrophe, __double_quote };
+
+// [format.string.escaped]/2
+template <class _CharT>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool __is_escaped_sequence_written(
+ basic_string<_CharT>& __str, char32_t __value, bool __last_escaped, __escape_quotation_mark __mark) {
+ // 2.2.1.1 - Mapped character in [tab:format.escape.sequences]
+ switch (__value) {
+ case _CharT('\t'):
+ __str += _LIBCPP_STATICALLY_WIDEN(_CharT, "\\t");
+ return true;
+ case _CharT('\n'):
+ __str += _LIBCPP_STATICALLY_WIDEN(_CharT, "\\n");
+ return true;
+ case _CharT('\r'):
+ __str += _LIBCPP_STATICALLY_WIDEN(_CharT, "\\r");
+ return true;
+ case _CharT('\''):
+ if (__mark == __escape_quotation_mark::__apostrophe)
+ __str += _LIBCPP_STATICALLY_WIDEN(_CharT, R"(\')");
+ else
+ __str += __value;
+ return true;
+ case _CharT('"'):
+ if (__mark == __escape_quotation_mark::__double_quote)
+ __str += _LIBCPP_STATICALLY_WIDEN(_CharT, R"(\")");
+ else
+ __str += __value;
+ return true;
+ case _CharT('\\'):
+ __str += _LIBCPP_STATICALLY_WIDEN(_CharT, R"(\\)");
+ return true;
+
+ // 2.2.1.2 - Space
+ case _CharT(' '):
+ __str += __value;
+ return true;
+ }
+
+ // 2.2.2
+ // Otherwise, if X is a shift sequence, the effect on E and further
+ // decoding of S is unspecified.
+ // For now shift sequences are ignored and treated as Unicode. Other parts
+ // of the format library do the same. It's unknown how ostream treats them.
+ // TODO FMT determine what to do with shift sequences.
+
+ // 2.2.1.2.1 and 2.2.1.2.2 - Escape
+ return __formatter::__is_escaped_sequence_written(__str, __last_escaped, __formatter::__to_char32(__value));
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI void
+__escape(basic_string<_CharT>& __str, basic_string_view<_CharT> __values, __escape_quotation_mark __mark) {
+ __unicode::__code_point_view<_CharT> __view{__values.begin(), __values.end()};
+
+ // When the first code unit has the property Grapheme_Extend=Yes it needs to
+ // be escaped. This happens when the previous code unit was also escaped.
+ bool __escape = true;
+ while (!__view.__at_end()) {
+ auto __first = __view.__position();
+ typename __unicode::__consume_result __result = __view.__consume();
+ if (__result.__status == __unicode::__consume_result::__ok) {
+ __escape = __formatter::__is_escaped_sequence_written(__str, __result.__code_point, __escape, __mark);
+ if (!__escape)
+ // 2.2.1.3 - Add the character
+ ranges::copy(__first, __view.__position(), std::back_insert_iterator(__str));
+ } else {
+ // 2.2.3 sequence of ill-formed code units
+ ranges::for_each(__first, __view.__position(), [&](_CharT __value) {
+ __formatter::__write_escape_ill_formed_code_unit(__str, __formatter::__to_char32(__value));
+ });
+ }
+ }
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__format_escaped_char(_CharT __value,
+ output_iterator<const _CharT&> auto __out_it,
+ __format_spec::__parsed_specifications<_CharT> __specs) -> decltype(__out_it) {
+ basic_string<_CharT> __str;
+ __str += _CharT('\'');
+ __formatter::__escape(__str, basic_string_view{std::addressof(__value), 1}, __escape_quotation_mark::__apostrophe);
+ __str += _CharT('\'');
+ return __formatter::__write(__str.data(), __str.data() + __str.size(), std::move(__out_it), __specs, __str.size());
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI auto
+__format_escaped_string(basic_string_view<_CharT> __values,
+ output_iterator<const _CharT&> auto __out_it,
+ __format_spec::__parsed_specifications<_CharT> __specs) -> decltype(__out_it) {
+ basic_string<_CharT> __str;
+ __str += _CharT('"');
+ __formatter::__escape(__str, __values, __escape_quotation_mark::__double_quote);
+ __str += _CharT('"');
+ return __formatter::__write_string(basic_string_view{__str}, std::move(__out_it), __specs);
+}
+
+#endif // _LIBCPP_STD_VER >= 23
+
+} // namespace __formatter
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FORMAT_WRITE_ESCAPED_H
diff --git a/libcxx/include/__cxx03/__functional/binary_function.h b/libcxx/include/__cxx03/__functional/binary_function.h
new file mode 100644
index 00000000000000..ddee3b170311f0
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/binary_function.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_BINARY_FUNCTION_H
+#define _LIBCPP___FUNCTIONAL_BINARY_FUNCTION_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNARY_BINARY_FUNCTION)
+
+template <class _Arg1, class _Arg2, class _Result>
+struct _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 binary_function {
+ typedef _Arg1 first_argument_type;
+ typedef _Arg2 second_argument_type;
+ typedef _Result result_type;
+};
+
+#endif // _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNARY_BINARY_FUNCTION)
+
+template <class _Arg1, class _Arg2, class _Result>
+struct __binary_function_keep_layout_base {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using first_argument_type _LIBCPP_DEPRECATED_IN_CXX17 = _Arg1;
+ using second_argument_type _LIBCPP_DEPRECATED_IN_CXX17 = _Arg2;
+ using result_type _LIBCPP_DEPRECATED_IN_CXX17 = _Result;
+#endif
+};
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNARY_BINARY_FUNCTION)
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wdeprecated-declarations")
+template <class _Arg1, class _Arg2, class _Result>
+using __binary_function = binary_function<_Arg1, _Arg2, _Result>;
+_LIBCPP_DIAGNOSTIC_POP
+#else
+template <class _Arg1, class _Arg2, class _Result>
+using __binary_function = __binary_function_keep_layout_base<_Arg1, _Arg2, _Result>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_BINARY_FUNCTION_H
diff --git a/libcxx/include/__cxx03/__functional/binary_negate.h b/libcxx/include/__cxx03/__functional/binary_negate.h
new file mode 100644
index 00000000000000..ce52b5ae9fc499
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/binary_negate.h
@@ -0,0 +1,51 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_BINARY_NEGATE_H
+#define _LIBCPP___FUNCTIONAL_BINARY_NEGATE_H
+
+#include <__config>
+#include <__functional/binary_function.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_NEGATORS)
+
+template <class _Predicate>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 binary_negate
+ : public __binary_function<typename _Predicate::first_argument_type,
+ typename _Predicate::second_argument_type,
+ bool> {
+ _Predicate __pred_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit _LIBCPP_CONSTEXPR_SINCE_CXX14 binary_negate(const _Predicate& __pred)
+ : __pred_(__pred) {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(
+ const typename _Predicate::first_argument_type& __x, const typename _Predicate::second_argument_type& __y) const {
+ return !__pred_(__x, __y);
+ }
+};
+
+template <class _Predicate>
+_LIBCPP_DEPRECATED_IN_CXX17 inline _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI binary_negate<_Predicate>
+not2(const _Predicate& __pred) {
+ return binary_negate<_Predicate>(__pred);
+}
+
+#endif // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_NEGATORS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_BINARY_NEGATE_H
diff --git a/libcxx/include/__cxx03/__functional/bind.h b/libcxx/include/__cxx03/__functional/bind.h
new file mode 100644
index 00000000000000..b4f46441da5074
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/bind.h
@@ -0,0 +1,296 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_BIND_H
+#define _LIBCPP___FUNCTIONAL_BIND_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__functional/weak_result_type.h>
+#include <__fwd/functional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_reference_wrapper.h>
+#include <__type_traits/is_void.h>
+#include <cstddef>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct is_bind_expression
+ : _If< _IsSame<_Tp, __remove_cvref_t<_Tp> >::value, false_type, is_bind_expression<__remove_cvref_t<_Tp> > > {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_bind_expression_v = is_bind_expression<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct is_placeholder
+ : _If< _IsSame<_Tp, __remove_cvref_t<_Tp> >::value,
+ integral_constant<int, 0>,
+ is_placeholder<__remove_cvref_t<_Tp> > > {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr int is_placeholder_v = is_placeholder<_Tp>::value;
+#endif
+
+namespace placeholders {
+
+template <int _Np>
+struct __ph {};
+
+// C++17 recommends that we implement placeholders as `inline constexpr`, but allows
+// implementing them as `extern <implementation-defined>`. Libc++ implements them as
+// `extern const` in all standard modes to avoid an ABI break in C++03: making them
+// `inline constexpr` requires removing their definition in the shared library to
+// avoid ODR violations, which is an ABI break.
+//
+// In practice, since placeholders are empty, `extern const` is almost impossible
+// to distinguish from `inline constexpr` from a usage stand point.
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<1> _1;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<2> _2;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<3> _3;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<4> _4;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<5> _5;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<6> _6;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<7> _7;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<8> _8;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<9> _9;
+_LIBCPP_EXPORTED_FROM_ABI extern const __ph<10> _10;
+
+} // namespace placeholders
+
+template <int _Np>
+struct is_placeholder<placeholders::__ph<_Np> > : public integral_constant<int, _Np> {};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Uj>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& __mu(reference_wrapper<_Tp> __t, _Uj&) {
+ return __t.get();
+}
+
+template <class _Ti, class... _Uj, size_t... _Indx>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename __invoke_of<_Ti&, _Uj...>::type
+__mu_expand(_Ti& __ti, tuple<_Uj...>& __uj, __tuple_indices<_Indx...>) {
+ return __ti(std::forward<_Uj>(std::get<_Indx>(__uj))...);
+}
+
+template <class _Ti, class... _Uj, __enable_if_t<is_bind_expression<_Ti>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename __invoke_of<_Ti&, _Uj...>::type
+__mu(_Ti& __ti, tuple<_Uj...>& __uj) {
+ typedef typename __make_tuple_indices<sizeof...(_Uj)>::type __indices;
+ return std::__mu_expand(__ti, __uj, __indices());
+}
+
+template <bool _IsPh, class _Ti, class _Uj>
+struct __mu_return2 {};
+
+template <class _Ti, class _Uj>
+struct __mu_return2<true, _Ti, _Uj> {
+ typedef typename tuple_element<is_placeholder<_Ti>::value - 1, _Uj>::type type;
+};
+
+template <class _Ti, class _Uj, __enable_if_t<0 < is_placeholder<_Ti>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+typename __mu_return2<0 < is_placeholder<_Ti>::value, _Ti, _Uj>::type
+__mu(_Ti&, _Uj& __uj) {
+ const size_t __indx = is_placeholder<_Ti>::value - 1;
+ return std::forward<typename tuple_element<__indx, _Uj>::type>(std::get<__indx>(__uj));
+}
+
+template <class _Ti,
+ class _Uj,
+ __enable_if_t<!is_bind_expression<_Ti>::value && is_placeholder<_Ti>::value == 0 &&
+ !__is_reference_wrapper<_Ti>::value,
+ int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Ti& __mu(_Ti& __ti, _Uj&) {
+ return __ti;
+}
+
+template <class _Ti, bool _IsReferenceWrapper, bool _IsBindEx, bool _IsPh, class _TupleUj>
+struct __mu_return_impl;
+
+template <bool _Invokable, class _Ti, class... _Uj>
+struct __mu_return_invokable // false
+{
+ typedef __nat type;
+};
+
+template <class _Ti, class... _Uj>
+struct __mu_return_invokable<true, _Ti, _Uj...> {
+ typedef typename __invoke_of<_Ti&, _Uj...>::type type;
+};
+
+template <class _Ti, class... _Uj>
+struct __mu_return_impl<_Ti, false, true, false, tuple<_Uj...> >
+ : public __mu_return_invokable<__invokable<_Ti&, _Uj...>::value, _Ti, _Uj...> {};
+
+template <class _Ti, class _TupleUj>
+struct __mu_return_impl<_Ti, false, false, true, _TupleUj> {
+ typedef typename tuple_element<is_placeholder<_Ti>::value - 1, _TupleUj>::type&& type;
+};
+
+template <class _Ti, class _TupleUj>
+struct __mu_return_impl<_Ti, true, false, false, _TupleUj> {
+ typedef typename _Ti::type& type;
+};
+
+template <class _Ti, class _TupleUj>
+struct __mu_return_impl<_Ti, false, false, false, _TupleUj> {
+ typedef _Ti& type;
+};
+
+template <class _Ti, class _TupleUj>
+struct __mu_return
+ : public __mu_return_impl<
+ _Ti,
+ __is_reference_wrapper<_Ti>::value,
+ is_bind_expression<_Ti>::value,
+ 0 < is_placeholder<_Ti>::value && is_placeholder<_Ti>::value <= tuple_size<_TupleUj>::value,
+ _TupleUj> {};
+
+template <class _Fp, class _BoundArgs, class _TupleUj>
+struct __is_valid_bind_return {
+ static const bool value = false;
+};
+
+template <class _Fp, class... _BoundArgs, class _TupleUj>
+struct __is_valid_bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj> {
+ static const bool value = __invokable<_Fp, typename __mu_return<_BoundArgs, _TupleUj>::type...>::value;
+};
+
+template <class _Fp, class... _BoundArgs, class _TupleUj>
+struct __is_valid_bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj> {
+ static const bool value = __invokable<_Fp, typename __mu_return<const _BoundArgs, _TupleUj>::type...>::value;
+};
+
+template <class _Fp, class _BoundArgs, class _TupleUj, bool = __is_valid_bind_return<_Fp, _BoundArgs, _TupleUj>::value>
+struct __bind_return;
+
+template <class _Fp, class... _BoundArgs, class _TupleUj>
+struct __bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj, true> {
+ typedef typename __invoke_of< _Fp&, typename __mu_return< _BoundArgs, _TupleUj >::type... >::type type;
+};
+
+template <class _Fp, class... _BoundArgs, class _TupleUj>
+struct __bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj, true> {
+ typedef typename __invoke_of< _Fp&, typename __mu_return< const _BoundArgs, _TupleUj >::type... >::type type;
+};
+
+template <class _Fp, class _BoundArgs, size_t... _Indx, class _Args>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename __bind_return<_Fp, _BoundArgs, _Args>::type
+__apply_functor(_Fp& __f, _BoundArgs& __bound_args, __tuple_indices<_Indx...>, _Args&& __args) {
+ return std::__invoke(__f, std::__mu(std::get<_Indx>(__bound_args), __args)...);
+}
+
+template <class _Fp, class... _BoundArgs>
+class __bind : public __weak_result_type<__decay_t<_Fp> > {
+protected:
+ using _Fd = __decay_t<_Fp>;
+ typedef tuple<__decay_t<_BoundArgs>...> _Td;
+
+private:
+ _Fd __f_;
+ _Td __bound_args_;
+
+ typedef typename __make_tuple_indices<sizeof...(_BoundArgs)>::type __indices;
+
+public:
+ template <
+ class _Gp,
+ class... _BA,
+ __enable_if_t<is_constructible<_Fd, _Gp>::value && !is_same<__libcpp_remove_reference_t<_Gp>, __bind>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit __bind(_Gp&& __f, _BA&&... __bound_args)
+ : __f_(std::forward<_Gp>(__f)), __bound_args_(std::forward<_BA>(__bound_args)...) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type
+ operator()(_Args&&... __args) {
+ return std::__apply_functor(__f_, __bound_args_, __indices(), tuple<_Args&&...>(std::forward<_Args>(__args)...));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ typename __bind_return<const _Fd, const _Td, tuple<_Args&&...> >::type
+ operator()(_Args&&... __args) const {
+ return std::__apply_functor(__f_, __bound_args_, __indices(), tuple<_Args&&...>(std::forward<_Args>(__args)...));
+ }
+};
+
+template <class _Fp, class... _BoundArgs>
+struct is_bind_expression<__bind<_Fp, _BoundArgs...> > : public true_type {};
+
+template <class _Rp, class _Fp, class... _BoundArgs>
+class __bind_r : public __bind<_Fp, _BoundArgs...> {
+ typedef __bind<_Fp, _BoundArgs...> base;
+ typedef typename base::_Fd _Fd;
+ typedef typename base::_Td _Td;
+
+public:
+ typedef _Rp result_type;
+
+ template <
+ class _Gp,
+ class... _BA,
+ __enable_if_t<is_constructible<_Fd, _Gp>::value && !is_same<__libcpp_remove_reference_t<_Gp>, __bind_r>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit __bind_r(_Gp&& __f, _BA&&... __bound_args)
+ : base(std::forward<_Gp>(__f), std::forward<_BA>(__bound_args)...) {}
+
+ template <
+ class... _Args,
+ __enable_if_t<is_convertible<typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type, result_type>::value ||
+ is_void<_Rp>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 result_type operator()(_Args&&... __args) {
+ typedef __invoke_void_return_wrapper<_Rp> _Invoker;
+ return _Invoker::__call(static_cast<base&>(*this), std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args,
+ __enable_if_t<is_convertible<typename __bind_return<const _Fd, const _Td, tuple<_Args&&...> >::type,
+ result_type>::value ||
+ is_void<_Rp>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 result_type operator()(_Args&&... __args) const {
+ typedef __invoke_void_return_wrapper<_Rp> _Invoker;
+ return _Invoker::__call(static_cast<base const&>(*this), std::forward<_Args>(__args)...);
+ }
+};
+
+template <class _Rp, class _Fp, class... _BoundArgs>
+struct is_bind_expression<__bind_r<_Rp, _Fp, _BoundArgs...> > : public true_type {};
+
+template <class _Fp, class... _BoundArgs>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bind<_Fp, _BoundArgs...>
+bind(_Fp&& __f, _BoundArgs&&... __bound_args) {
+ typedef __bind<_Fp, _BoundArgs...> type;
+ return type(std::forward<_Fp>(__f), std::forward<_BoundArgs>(__bound_args)...);
+}
+
+template <class _Rp, class _Fp, class... _BoundArgs>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bind_r<_Rp, _Fp, _BoundArgs...>
+bind(_Fp&& __f, _BoundArgs&&... __bound_args) {
+ typedef __bind_r<_Rp, _Fp, _BoundArgs...> type;
+ return type(std::forward<_Fp>(__f), std::forward<_BoundArgs>(__bound_args)...);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_BIND_H
diff --git a/libcxx/include/__cxx03/__functional/bind_back.h b/libcxx/include/__cxx03/__functional/bind_back.h
new file mode 100644
index 00000000000000..e44768d2283c08
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/bind_back.h
@@ -0,0 +1,83 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_BIND_BACK_H
+#define _LIBCPP___FUNCTIONAL_BIND_BACK_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__functional/perfect_forward.h>
+#include <__type_traits/decay.h>
+#include <__utility/forward.h>
+#include <__utility/integer_sequence.h>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <size_t _NBound, class = make_index_sequence<_NBound>>
+struct __bind_back_op;
+
+template <size_t _NBound, size_t... _Ip>
+struct __bind_back_op<_NBound, index_sequence<_Ip...>> {
+ template <class _Fn, class _BoundArgs, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Fn&& __f, _BoundArgs&& __bound_args, _Args&&... __args) const
+ noexcept(noexcept(std::invoke(std::forward<_Fn>(__f),
+ std::forward<_Args>(__args)...,
+ std::get<_Ip>(std::forward<_BoundArgs>(__bound_args))...)))
+ -> decltype(std::invoke(std::forward<_Fn>(__f),
+ std::forward<_Args>(__args)...,
+ std::get<_Ip>(std::forward<_BoundArgs>(__bound_args))...)) {
+ return std::invoke(std::forward<_Fn>(__f),
+ std::forward<_Args>(__args)...,
+ std::get<_Ip>(std::forward<_BoundArgs>(__bound_args))...);
+ }
+};
+
+template <class _Fn, class _BoundArgs>
+struct __bind_back_t : __perfect_forward<__bind_back_op<tuple_size_v<_BoundArgs>>, _Fn, _BoundArgs> {
+ using __perfect_forward<__bind_back_op<tuple_size_v<_BoundArgs>>, _Fn, _BoundArgs>::__perfect_forward;
+};
+
+template <class _Fn, class... _Args>
+ requires is_constructible_v<decay_t<_Fn>, _Fn> && is_move_constructible_v<decay_t<_Fn>> &&
+ (is_constructible_v<decay_t<_Args>, _Args> && ...) && (is_move_constructible_v<decay_t<_Args>> && ...)
+_LIBCPP_HIDE_FROM_ABI constexpr auto __bind_back(_Fn&& __f, _Args&&... __args) noexcept(
+ noexcept(__bind_back_t<decay_t<_Fn>, tuple<decay_t<_Args>...>>(
+ std::forward<_Fn>(__f), std::forward_as_tuple(std::forward<_Args>(__args)...))))
+ -> decltype(__bind_back_t<decay_t<_Fn>, tuple<decay_t<_Args>...>>(
+ std::forward<_Fn>(__f), std::forward_as_tuple(std::forward<_Args>(__args)...))) {
+ return __bind_back_t<decay_t<_Fn>, tuple<decay_t<_Args>...>>(
+ std::forward<_Fn>(__f), std::forward_as_tuple(std::forward<_Args>(__args)...));
+}
+
+# if _LIBCPP_STD_VER >= 23
+template <class _Fn, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr auto bind_back(_Fn&& __f, _Args&&... __args) {
+ static_assert(is_constructible_v<decay_t<_Fn>, _Fn>, "bind_back requires decay_t<F> to be constructible from F");
+ static_assert(is_move_constructible_v<decay_t<_Fn>>, "bind_back requires decay_t<F> to be move constructible");
+ static_assert((is_constructible_v<decay_t<_Args>, _Args> && ...),
+ "bind_back requires all decay_t<Args> to be constructible from respective Args");
+ static_assert((is_move_constructible_v<decay_t<_Args>> && ...),
+ "bind_back requires all decay_t<Args> to be move constructible");
+ return __bind_back_t<decay_t<_Fn>, tuple<decay_t<_Args>...>>(
+ std::forward<_Fn>(__f), std::forward_as_tuple(std::forward<_Args>(__args)...));
+}
+# endif // _LIBCPP_STD_VER >= 23
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_BIND_BACK_H
diff --git a/libcxx/include/__cxx03/__functional/bind_front.h b/libcxx/include/__cxx03/__functional/bind_front.h
new file mode 100644
index 00000000000000..87ef3affe80b63
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/bind_front.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_BIND_FRONT_H
+#define _LIBCPP___FUNCTIONAL_BIND_FRONT_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__functional/perfect_forward.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+struct __bind_front_op {
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Args&&... __args) const noexcept(
+ noexcept(std::invoke(std::forward<_Args>(__args)...))) -> decltype(std::invoke(std::forward<_Args>(__args)...)) {
+ return std::invoke(std::forward<_Args>(__args)...);
+ }
+};
+
+template <class _Fn, class... _BoundArgs>
+struct __bind_front_t : __perfect_forward<__bind_front_op, _Fn, _BoundArgs...> {
+ using __perfect_forward<__bind_front_op, _Fn, _BoundArgs...>::__perfect_forward;
+};
+
+template <class _Fn, class... _Args>
+ requires is_constructible_v<decay_t<_Fn>, _Fn> && is_move_constructible_v<decay_t<_Fn>> &&
+ (is_constructible_v<decay_t<_Args>, _Args> && ...) && (is_move_constructible_v<decay_t<_Args>> && ...)
+_LIBCPP_HIDE_FROM_ABI constexpr auto bind_front(_Fn&& __f, _Args&&... __args) {
+ return __bind_front_t<decay_t<_Fn>, decay_t<_Args>...>(std::forward<_Fn>(__f), std::forward<_Args>(__args)...);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_BIND_FRONT_H
diff --git a/libcxx/include/__cxx03/__functional/binder1st.h b/libcxx/include/__cxx03/__functional/binder1st.h
new file mode 100644
index 00000000000000..04b51fefab70a9
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/binder1st.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_BINDER1ST_H
+#define _LIBCPP___FUNCTIONAL_BINDER1ST_H
+
+#include <__config>
+#include <__functional/unary_function.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+template <class _Operation>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 binder1st
+ : public __unary_function<typename _Operation::second_argument_type, typename _Operation::result_type> {
+protected:
+ _Operation op;
+ typename _Operation::first_argument_type value;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI binder1st(const _Operation& __x, const typename _Operation::first_argument_type __y)
+ : op(__x), value(__y) {}
+ _LIBCPP_HIDE_FROM_ABI typename _Operation::result_type
+ operator()(typename _Operation::second_argument_type& __x) const {
+ return op(value, __x);
+ }
+ _LIBCPP_HIDE_FROM_ABI typename _Operation::result_type
+ operator()(const typename _Operation::second_argument_type& __x) const {
+ return op(value, __x);
+ }
+};
+
+template <class _Operation, class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI binder1st<_Operation>
+bind1st(const _Operation& __op, const _Tp& __x) {
+ return binder1st<_Operation>(__op, __x);
+}
+
+#endif // _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_BINDER1ST_H
diff --git a/libcxx/include/__cxx03/__functional/binder2nd.h b/libcxx/include/__cxx03/__functional/binder2nd.h
new file mode 100644
index 00000000000000..9d22e4430b1b34
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/binder2nd.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_BINDER2ND_H
+#define _LIBCPP___FUNCTIONAL_BINDER2ND_H
+
+#include <__config>
+#include <__functional/unary_function.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+template <class _Operation>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 binder2nd
+ : public __unary_function<typename _Operation::first_argument_type, typename _Operation::result_type> {
+protected:
+ _Operation op;
+ typename _Operation::second_argument_type value;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI binder2nd(const _Operation& __x, const typename _Operation::second_argument_type __y)
+ : op(__x), value(__y) {}
+ _LIBCPP_HIDE_FROM_ABI typename _Operation::result_type
+ operator()(typename _Operation::first_argument_type& __x) const {
+ return op(__x, value);
+ }
+ _LIBCPP_HIDE_FROM_ABI typename _Operation::result_type
+ operator()(const typename _Operation::first_argument_type& __x) const {
+ return op(__x, value);
+ }
+};
+
+template <class _Operation, class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI binder2nd<_Operation>
+bind2nd(const _Operation& __op, const _Tp& __x) {
+ return binder2nd<_Operation>(__op, __x);
+}
+
+#endif // _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_BINDER2ND_H
diff --git a/libcxx/include/__cxx03/__functional/boyer_moore_searcher.h b/libcxx/include/__cxx03/__functional/boyer_moore_searcher.h
new file mode 100644
index 00000000000000..648b60c5052191
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/boyer_moore_searcher.h
@@ -0,0 +1,306 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_BOYER_MOORE_SEARCHER_H
+#define _LIBCPP___FUNCTIONAL_BOYER_MOORE_SEARCHER_H
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#include <__algorithm/fill_n.h>
+#include <__config>
+#include <__functional/hash.h>
+#include <__functional/operations.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/shared_ptr.h>
+#include <__type_traits/make_unsigned.h>
+#include <__utility/pair.h>
+#include <array>
+#include <unordered_map>
+#include <vector>
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Key, class _Value, class _Hash, class _BinaryPredicate, bool /*useArray*/>
+class _BMSkipTable;
+
+// General case for BM data searching; use a map
+template <class _Key, class _Value, class _Hash, class _BinaryPredicate>
+class _BMSkipTable<_Key, _Value, _Hash, _BinaryPredicate, false> {
+private:
+ using value_type = _Value;
+ using key_type = _Key;
+
+ const value_type __default_value_;
+ unordered_map<_Key, _Value, _Hash, _BinaryPredicate> __table_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit _BMSkipTable(
+ size_t __sz, value_type __default_value, _Hash __hash, _BinaryPredicate __pred)
+ : __default_value_(__default_value), __table_(__sz, __hash, __pred) {}
+
+ _LIBCPP_HIDE_FROM_ABI void insert(const key_type& __key, value_type __val) { __table_[__key] = __val; }
+
+ _LIBCPP_HIDE_FROM_ABI value_type operator[](const key_type& __key) const {
+ auto __it = __table_.find(__key);
+ return __it == __table_.end() ? __default_value_ : __it->second;
+ }
+};
+
+// Special case small numeric values; use an array
+template <class _Key, class _Value, class _Hash, class _BinaryPredicate>
+class _BMSkipTable<_Key, _Value, _Hash, _BinaryPredicate, true> {
+private:
+ using value_type = _Value;
+ using key_type = _Key;
+
+ using unsigned_key_type = make_unsigned_t<key_type>;
+ std::array<value_type, 256> __table_;
+ static_assert(numeric_limits<unsigned_key_type>::max() < 256);
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit _BMSkipTable(size_t, value_type __default_value, _Hash, _BinaryPredicate) {
+ std::fill_n(__table_.data(), __table_.size(), __default_value);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(key_type __key, value_type __val) {
+ __table_[static_cast<unsigned_key_type>(__key)] = __val;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI value_type operator[](key_type __key) const {
+ return __table_[static_cast<unsigned_key_type>(__key)];
+ }
+};
+
+template <class _RandomAccessIterator1,
+ class _Hash = hash<typename iterator_traits<_RandomAccessIterator1>::value_type>,
+ class _BinaryPredicate = equal_to<>>
+class _LIBCPP_TEMPLATE_VIS boyer_moore_searcher {
+private:
+ using difference_type = typename std::iterator_traits<_RandomAccessIterator1>::difference_type;
+ using value_type = typename std::iterator_traits<_RandomAccessIterator1>::value_type;
+ using __skip_table_type =
+ _BMSkipTable<value_type,
+ difference_type,
+ _Hash,
+ _BinaryPredicate,
+ is_integral_v<value_type> && sizeof(value_type) == 1 && is_same_v<_Hash, hash<value_type>> &&
+ is_same_v<_BinaryPredicate, equal_to<>>>;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI boyer_moore_searcher(
+ _RandomAccessIterator1 __first,
+ _RandomAccessIterator1 __last,
+ _Hash __hash = _Hash(),
+ _BinaryPredicate __pred = _BinaryPredicate())
+ : __first_(__first),
+ __last_(__last),
+ __pred_(__pred),
+ __pattern_length_(__last - __first),
+ __skip_table_(std::make_shared<__skip_table_type>(__pattern_length_, -1, __hash, __pred_)),
+ __suffix_(std::__allocate_shared_unbounded_array<difference_type[]>(
+ allocator<difference_type>(), __pattern_length_ + 1)) {
+ difference_type __i = 0;
+ while (__first != __last) {
+ __skip_table_->insert(*__first, __i);
+ ++__first;
+ ++__i;
+ }
+ __build_suffix_table(__first_, __last_, __pred_);
+ }
+
+ template <class _RandomAccessIterator2>
+ _LIBCPP_HIDE_FROM_ABI pair<_RandomAccessIterator2, _RandomAccessIterator2>
+ operator()(_RandomAccessIterator2 __first, _RandomAccessIterator2 __last) const {
+ static_assert(__is_same_uncvref<typename iterator_traits<_RandomAccessIterator1>::value_type,
+ typename iterator_traits<_RandomAccessIterator2>::value_type>::value,
+ "Corpus and Pattern iterators must point to the same type");
+ if (__first == __last)
+ return std::make_pair(__last, __last);
+ if (__first_ == __last_)
+ return std::make_pair(__first, __first);
+
+ if (__pattern_length_ > (__last - __first))
+ return std::make_pair(__last, __last);
+ return __search(__first, __last);
+ }
+
+private:
+ _RandomAccessIterator1 __first_;
+ _RandomAccessIterator1 __last_;
+ _BinaryPredicate __pred_;
+ difference_type __pattern_length_;
+ shared_ptr<__skip_table_type> __skip_table_;
+ shared_ptr<difference_type[]> __suffix_;
+
+ template <class _RandomAccessIterator2>
+ _LIBCPP_HIDE_FROM_ABI pair<_RandomAccessIterator2, _RandomAccessIterator2>
+ __search(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const {
+ _RandomAccessIterator2 __current = __f;
+ const _RandomAccessIterator2 __last = __l - __pattern_length_;
+ const __skip_table_type& __skip_table = *__skip_table_;
+
+ while (__current <= __last) {
+ difference_type __j = __pattern_length_;
+ while (__pred_(__first_[__j - 1], __current[__j - 1])) {
+ --__j;
+ if (__j == 0)
+ return std::make_pair(__current, __current + __pattern_length_);
+ }
+
+ difference_type __k = __skip_table[__current[__j - 1]];
+ difference_type __m = __j - __k - 1;
+ if (__k < __j && __m > __suffix_[__j])
+ __current += __m;
+ else
+ __current += __suffix_[__j];
+ }
+ return std::make_pair(__l, __l);
+ }
+
+ template <class _Iterator, class _Container>
+ _LIBCPP_HIDE_FROM_ABI void
+ __compute_bm_prefix(_Iterator __first, _Iterator __last, _BinaryPredicate __pred, _Container& __prefix) {
+ const size_t __count = __last - __first;
+
+ __prefix[0] = 0;
+ size_t __k = 0;
+
+ for (size_t __i = 1; __i != __count; ++__i) {
+ while (__k > 0 && !__pred(__first[__k], __first[__i]))
+ __k = __prefix[__k - 1];
+
+ if (__pred(__first[__k], __first[__i]))
+ ++__k;
+ __prefix[__i] = __k;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void
+ __build_suffix_table(_RandomAccessIterator1 __first, _RandomAccessIterator1 __last, _BinaryPredicate __pred) {
+ const size_t __count = __last - __first;
+
+ if (__count == 0)
+ return;
+
+ vector<difference_type> __scratch(__count);
+
+ __compute_bm_prefix(__first, __last, __pred, __scratch);
+ for (size_t __i = 0; __i <= __count; ++__i)
+ __suffix_[__i] = __count - __scratch[__count - 1];
+
+ using _ReverseIter = reverse_iterator<_RandomAccessIterator1>;
+ __compute_bm_prefix(_ReverseIter(__last), _ReverseIter(__first), __pred, __scratch);
+
+ for (size_t __i = 0; __i != __count; ++__i) {
+ const size_t __j = __count - __scratch[__i];
+ const difference_type __k = __i - __scratch[__i] + 1;
+
+ if (__suffix_[__j] > __k)
+ __suffix_[__j] = __k;
+ }
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(boyer_moore_searcher);
+
+template <class _RandomAccessIterator1,
+ class _Hash = hash<typename iterator_traits<_RandomAccessIterator1>::value_type>,
+ class _BinaryPredicate = equal_to<>>
+class _LIBCPP_TEMPLATE_VIS boyer_moore_horspool_searcher {
+private:
+ using difference_type = typename iterator_traits<_RandomAccessIterator1>::difference_type;
+ using value_type = typename iterator_traits<_RandomAccessIterator1>::value_type;
+ using __skip_table_type =
+ _BMSkipTable<value_type,
+ difference_type,
+ _Hash,
+ _BinaryPredicate,
+ is_integral_v<value_type> && sizeof(value_type) == 1 && is_same_v<_Hash, hash<value_type>> &&
+ is_same_v<_BinaryPredicate, equal_to<>>>;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI boyer_moore_horspool_searcher(
+ _RandomAccessIterator1 __first,
+ _RandomAccessIterator1 __last,
+ _Hash __hash = _Hash(),
+ _BinaryPredicate __pred = _BinaryPredicate())
+ : __first_(__first),
+ __last_(__last),
+ __pred_(__pred),
+ __pattern_length_(__last - __first),
+ __skip_table_(std::make_shared<__skip_table_type>(__pattern_length_, __pattern_length_, __hash, __pred_)) {
+ if (__first == __last)
+ return;
+ --__last;
+ difference_type __i = 0;
+ while (__first != __last) {
+ __skip_table_->insert(*__first, __pattern_length_ - 1 - __i);
+ ++__first;
+ ++__i;
+ }
+ }
+
+ template <class _RandomAccessIterator2>
+ _LIBCPP_HIDE_FROM_ABI pair<_RandomAccessIterator2, _RandomAccessIterator2>
+ operator()(_RandomAccessIterator2 __first, _RandomAccessIterator2 __last) const {
+ static_assert(__is_same_uncvref<typename std::iterator_traits<_RandomAccessIterator1>::value_type,
+ typename std::iterator_traits<_RandomAccessIterator2>::value_type>::value,
+ "Corpus and Pattern iterators must point to the same type");
+ if (__first == __last)
+ return std::make_pair(__last, __last);
+ if (__first_ == __last_)
+ return std::make_pair(__first, __first);
+
+ if (__pattern_length_ > __last - __first)
+ return std::make_pair(__last, __last);
+
+ return __search(__first, __last);
+ }
+
+private:
+ _RandomAccessIterator1 __first_;
+ _RandomAccessIterator1 __last_;
+ _BinaryPredicate __pred_;
+ difference_type __pattern_length_;
+ shared_ptr<__skip_table_type> __skip_table_;
+
+ template <class _RandomAccessIterator2>
+ _LIBCPP_HIDE_FROM_ABI pair<_RandomAccessIterator2, _RandomAccessIterator2>
+ __search(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const {
+ _RandomAccessIterator2 __current = __f;
+ const _RandomAccessIterator2 __last = __l - __pattern_length_;
+ const __skip_table_type& __skip_table = *__skip_table_;
+
+ while (__current <= __last) {
+ difference_type __j = __pattern_length_;
+ while (__pred_(__first_[__j - 1], __current[__j - 1])) {
+ --__j;
+ if (__j == 0)
+ return std::make_pair(__current, __current + __pattern_length_);
+ }
+ __current += __skip_table[__current[__pattern_length_ - 1]];
+ }
+ return std::make_pair(__l, __l);
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(boyer_moore_horspool_searcher);
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___FUNCTIONAL_BOYER_MOORE_SEARCHER_H
diff --git a/libcxx/include/__cxx03/__functional/compose.h b/libcxx/include/__cxx03/__functional/compose.h
new file mode 100644
index 00000000000000..4b86dd37cd48a4
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/compose.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_COMPOSE_H
+#define _LIBCPP___FUNCTIONAL_COMPOSE_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__functional/perfect_forward.h>
+#include <__type_traits/decay.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+struct __compose_op {
+ template <class _Fn1, class _Fn2, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Fn1&& __f1, _Fn2&& __f2, _Args&&... __args) const noexcept(noexcept(
+ std::invoke(std::forward<_Fn1>(__f1), std::invoke(std::forward<_Fn2>(__f2), std::forward<_Args>(__args)...))))
+ -> decltype(std::invoke(std::forward<_Fn1>(__f1),
+ std::invoke(std::forward<_Fn2>(__f2), std::forward<_Args>(__args)...))) {
+ return std::invoke(std::forward<_Fn1>(__f1), std::invoke(std::forward<_Fn2>(__f2), std::forward<_Args>(__args)...));
+ }
+};
+
+template <class _Fn1, class _Fn2>
+struct __compose_t : __perfect_forward<__compose_op, _Fn1, _Fn2> {
+ using __perfect_forward<__compose_op, _Fn1, _Fn2>::__perfect_forward;
+};
+
+template <class _Fn1, class _Fn2>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __compose(_Fn1&& __f1, _Fn2&& __f2) noexcept(
+ noexcept(__compose_t<decay_t<_Fn1>, decay_t<_Fn2>>(std::forward<_Fn1>(__f1), std::forward<_Fn2>(__f2))))
+ -> decltype(__compose_t<decay_t<_Fn1>, decay_t<_Fn2>>(std::forward<_Fn1>(__f1), std::forward<_Fn2>(__f2))) {
+ return __compose_t<decay_t<_Fn1>, decay_t<_Fn2>>(std::forward<_Fn1>(__f1), std::forward<_Fn2>(__f2));
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_COMPOSE_H
diff --git a/libcxx/include/__cxx03/__functional/default_searcher.h b/libcxx/include/__cxx03/__functional/default_searcher.h
new file mode 100644
index 00000000000000..db89d10757c1b1
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/default_searcher.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_DEFAULT_SEARCHER_H
+#define _LIBCPP___FUNCTIONAL_DEFAULT_SEARCHER_H
+
+#include <__algorithm/search.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/operations.h>
+#include <__iterator/iterator_traits.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+// default searcher
+template <class _ForwardIterator, class _BinaryPredicate = equal_to<>>
+class _LIBCPP_TEMPLATE_VIS default_searcher {
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ default_searcher(_ForwardIterator __f, _ForwardIterator __l, _BinaryPredicate __p = _BinaryPredicate())
+ : __first_(__f), __last_(__l), __pred_(__p) {}
+
+ template <typename _ForwardIterator2>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator2, _ForwardIterator2>
+ operator()(_ForwardIterator2 __f, _ForwardIterator2 __l) const {
+ auto __proj = __identity();
+ return std::__search_impl(__f, __l, __first_, __last_, __pred_, __proj, __proj);
+ }
+
+private:
+ _ForwardIterator __first_;
+ _ForwardIterator __last_;
+ _BinaryPredicate __pred_;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(default_searcher);
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_DEFAULT_SEARCHER_H
diff --git a/libcxx/include/__cxx03/__functional/function.h b/libcxx/include/__cxx03/__functional/function.h
new file mode 100644
index 00000000000000..c7b98035e34bfa
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/function.h
@@ -0,0 +1,1048 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_FUNCTION_H
+#define _LIBCPP___FUNCTIONAL_FUNCTION_H
+
+#include <__assert>
+#include <__config>
+#include <__exception/exception.h>
+#include <__functional/binary_function.h>
+#include <__functional/invoke.h>
+#include <__functional/unary_function.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator.h>
+#include <__memory/allocator_destructor.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/builtin_new_allocator.h>
+#include <__memory/compressed_pair.h>
+#include <__memory/unique_ptr.h>
+#include <__type_traits/aligned_storage.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_core_convertible.h>
+#include <__type_traits/is_scalar.h>
+#include <__type_traits/is_trivially_constructible.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/strip_signature.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/piecewise_construct.h>
+#include <__utility/swap.h>
+#include <__verbose_abort>
+#include <new>
+#include <tuple>
+#include <typeinfo>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#ifndef _LIBCPP_CXX03_LANG
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// bad_function_call
+
+_LIBCPP_DIAGNOSTIC_PUSH
+# if !_LIBCPP_AVAILABILITY_HAS_BAD_FUNCTION_CALL_KEY_FUNCTION
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wweak-vtables")
+# endif
+class _LIBCPP_EXPORTED_FROM_ABI bad_function_call : public exception {
+public:
+ _LIBCPP_HIDE_FROM_ABI bad_function_call() _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_function_call(const bad_function_call&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_function_call& operator=(const bad_function_call&) _NOEXCEPT = default;
+// Note that when a key function is not used, every translation unit that uses
+// bad_function_call will end up containing a weak definition of the vtable and
+// typeinfo.
+# if _LIBCPP_AVAILABILITY_HAS_BAD_FUNCTION_CALL_KEY_FUNCTION
+ ~bad_function_call() _NOEXCEPT override;
+# else
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~bad_function_call() _NOEXCEPT override {}
+# endif
+
+# ifdef _LIBCPP_ABI_BAD_FUNCTION_CALL_GOOD_WHAT_MESSAGE
+ const char* what() const _NOEXCEPT override;
+# endif
+};
+_LIBCPP_DIAGNOSTIC_POP
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_bad_function_call() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw bad_function_call();
+# else
+ _LIBCPP_VERBOSE_ABORT("bad_function_call was thrown in -fno-exceptions mode");
+# endif
+}
+
+template <class _Fp>
+class _LIBCPP_TEMPLATE_VIS function; // undefined
+
+namespace __function {
+
+template <class _Rp>
+struct __maybe_derive_from_unary_function {};
+
+template <class _Rp, class _A1>
+struct __maybe_derive_from_unary_function<_Rp(_A1)> : public __unary_function<_A1, _Rp> {};
+
+template <class _Rp>
+struct __maybe_derive_from_binary_function {};
+
+template <class _Rp, class _A1, class _A2>
+struct __maybe_derive_from_binary_function<_Rp(_A1, _A2)> : public __binary_function<_A1, _A2, _Rp> {};
+
+template <class _Fp>
+_LIBCPP_HIDE_FROM_ABI bool __not_null(_Fp const&) {
+ return true;
+}
+
+template <class _Fp>
+_LIBCPP_HIDE_FROM_ABI bool __not_null(_Fp* __ptr) {
+ return __ptr;
+}
+
+template <class _Ret, class _Class>
+_LIBCPP_HIDE_FROM_ABI bool __not_null(_Ret _Class::*__ptr) {
+ return __ptr;
+}
+
+template <class _Fp>
+_LIBCPP_HIDE_FROM_ABI bool __not_null(function<_Fp> const& __f) {
+ return !!__f;
+}
+
+# ifdef _LIBCPP_HAS_EXTENSION_BLOCKS
+template <class _Rp, class... _Args>
+_LIBCPP_HIDE_FROM_ABI bool __not_null(_Rp (^__p)(_Args...)) {
+ return __p;
+}
+# endif
+
+} // namespace __function
+
+namespace __function {
+
+// __alloc_func holds a functor and an allocator.
+
+template <class _Fp, class _Ap, class _FB>
+class __alloc_func;
+template <class _Fp, class _FB>
+class __default_alloc_func;
+
+template <class _Fp, class _Ap, class _Rp, class... _ArgTypes>
+class __alloc_func<_Fp, _Ap, _Rp(_ArgTypes...)> {
+ __compressed_pair<_Fp, _Ap> __f_;
+
+public:
+ typedef _LIBCPP_NODEBUG _Fp _Target;
+ typedef _LIBCPP_NODEBUG _Ap _Alloc;
+
+ _LIBCPP_HIDE_FROM_ABI const _Target& __target() const { return __f_.first(); }
+
+ // WIN32 APIs may define __allocator, so use __get_allocator instead.
+ _LIBCPP_HIDE_FROM_ABI const _Alloc& __get_allocator() const { return __f_.second(); }
+
+ _LIBCPP_HIDE_FROM_ABI explicit __alloc_func(_Target&& __f)
+ : __f_(piecewise_construct, std::forward_as_tuple(std::move(__f)), std::forward_as_tuple()) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __alloc_func(const _Target& __f, const _Alloc& __a)
+ : __f_(piecewise_construct, std::forward_as_tuple(__f), std::forward_as_tuple(__a)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __alloc_func(const _Target& __f, _Alloc&& __a)
+ : __f_(piecewise_construct, std::forward_as_tuple(__f), std::forward_as_tuple(std::move(__a))) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __alloc_func(_Target&& __f, _Alloc&& __a)
+ : __f_(piecewise_construct, std::forward_as_tuple(std::move(__f)), std::forward_as_tuple(std::move(__a))) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Rp operator()(_ArgTypes&&... __arg) {
+ typedef __invoke_void_return_wrapper<_Rp> _Invoker;
+ return _Invoker::__call(__f_.first(), std::forward<_ArgTypes>(__arg)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __alloc_func* __clone() const {
+ typedef allocator_traits<_Alloc> __alloc_traits;
+ typedef __rebind_alloc<__alloc_traits, __alloc_func> _AA;
+ _AA __a(__f_.second());
+ typedef __allocator_destructor<_AA> _Dp;
+ unique_ptr<__alloc_func, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
+ ::new ((void*)__hold.get()) __alloc_func(__f_.first(), _Alloc(__a));
+ return __hold.release();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void destroy() _NOEXCEPT { __f_.~__compressed_pair<_Target, _Alloc>(); }
+
+ _LIBCPP_HIDE_FROM_ABI static void __destroy_and_delete(__alloc_func* __f) {
+ typedef allocator_traits<_Alloc> __alloc_traits;
+ typedef __rebind_alloc<__alloc_traits, __alloc_func> _FunAlloc;
+ _FunAlloc __a(__f->__get_allocator());
+ __f->destroy();
+ __a.deallocate(__f, 1);
+ }
+};
+
+template <class _Fp, class _Rp, class... _ArgTypes>
+class __default_alloc_func<_Fp, _Rp(_ArgTypes...)> {
+ _Fp __f_;
+
+public:
+ typedef _LIBCPP_NODEBUG _Fp _Target;
+
+ _LIBCPP_HIDE_FROM_ABI const _Target& __target() const { return __f_; }
+
+ _LIBCPP_HIDE_FROM_ABI explicit __default_alloc_func(_Target&& __f) : __f_(std::move(__f)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __default_alloc_func(const _Target& __f) : __f_(__f) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Rp operator()(_ArgTypes&&... __arg) {
+ typedef __invoke_void_return_wrapper<_Rp> _Invoker;
+ return _Invoker::__call(__f_, std::forward<_ArgTypes>(__arg)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __default_alloc_func* __clone() const {
+ __builtin_new_allocator::__holder_t __hold = __builtin_new_allocator::__allocate_type<__default_alloc_func>(1);
+ __default_alloc_func* __res = ::new ((void*)__hold.get()) __default_alloc_func(__f_);
+ (void)__hold.release();
+ return __res;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void destroy() _NOEXCEPT { __f_.~_Target(); }
+
+ _LIBCPP_HIDE_FROM_ABI static void __destroy_and_delete(__default_alloc_func* __f) {
+ __f->destroy();
+ __builtin_new_allocator::__deallocate_type<__default_alloc_func>(__f, 1);
+ }
+};
+
+// __base provides an abstract interface for copyable functors.
+
+template <class _Fp>
+class _LIBCPP_TEMPLATE_VIS __base;
+
+template <class _Rp, class... _ArgTypes>
+class __base<_Rp(_ArgTypes...)> {
+public:
+ __base(const __base&) = delete;
+ __base& operator=(const __base&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI __base() {}
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual ~__base() {}
+ virtual __base* __clone() const = 0;
+ virtual void __clone(__base*) const = 0;
+ virtual void destroy() _NOEXCEPT = 0;
+ virtual void destroy_deallocate() _NOEXCEPT = 0;
+ virtual _Rp operator()(_ArgTypes&&...) = 0;
+# ifndef _LIBCPP_HAS_NO_RTTI
+ virtual const void* target(const type_info&) const _NOEXCEPT = 0;
+ virtual const std::type_info& target_type() const _NOEXCEPT = 0;
+# endif // _LIBCPP_HAS_NO_RTTI
+};
+
+// __func implements __base for a given functor type.
+
+template <class _FD, class _Alloc, class _FB>
+class __func;
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+class __func<_Fp, _Alloc, _Rp(_ArgTypes...)> : public __base<_Rp(_ArgTypes...)> {
+ __alloc_func<_Fp, _Alloc, _Rp(_ArgTypes...)> __f_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __func(_Fp&& __f) : __f_(std::move(__f)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __func(const _Fp& __f, const _Alloc& __a) : __f_(__f, __a) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __func(const _Fp& __f, _Alloc&& __a) : __f_(__f, std::move(__a)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __func(_Fp&& __f, _Alloc&& __a) : __f_(std::move(__f), std::move(__a)) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual __base<_Rp(_ArgTypes...)>* __clone() const;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __clone(__base<_Rp(_ArgTypes...)>*) const;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void destroy() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void destroy_deallocate() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual _Rp operator()(_ArgTypes&&... __arg);
+# ifndef _LIBCPP_HAS_NO_RTTI
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual const void* target(const type_info&) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual const std::type_info& target_type() const _NOEXCEPT;
+# endif // _LIBCPP_HAS_NO_RTTI
+};
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+__base<_Rp(_ArgTypes...)>* __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone() const {
+ typedef allocator_traits<_Alloc> __alloc_traits;
+ typedef __rebind_alloc<__alloc_traits, __func> _Ap;
+ _Ap __a(__f_.__get_allocator());
+ typedef __allocator_destructor<_Ap> _Dp;
+ unique_ptr<__func, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
+ ::new ((void*)__hold.get()) __func(__f_.__target(), _Alloc(__a));
+ return __hold.release();
+}
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+void __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone(__base<_Rp(_ArgTypes...)>* __p) const {
+ ::new ((void*)__p) __func(__f_.__target(), __f_.__get_allocator());
+}
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+void __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy() _NOEXCEPT {
+ __f_.destroy();
+}
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+void __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy_deallocate() _NOEXCEPT {
+ typedef allocator_traits<_Alloc> __alloc_traits;
+ typedef __rebind_alloc<__alloc_traits, __func> _Ap;
+ _Ap __a(__f_.__get_allocator());
+ __f_.destroy();
+ __a.deallocate(this, 1);
+}
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+_Rp __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::operator()(_ArgTypes&&... __arg) {
+ return __f_(std::forward<_ArgTypes>(__arg)...);
+}
+
+# ifndef _LIBCPP_HAS_NO_RTTI
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+const void* __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target(const type_info& __ti) const _NOEXCEPT {
+ if (__ti == typeid(_Fp))
+ return std::addressof(__f_.__target());
+ return nullptr;
+}
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+const std::type_info& __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target_type() const _NOEXCEPT {
+ return typeid(_Fp);
+}
+
+# endif // _LIBCPP_HAS_NO_RTTI
+
+// __value_func creates a value-type from a __func.
+
+template <class _Fp>
+class __value_func;
+
+template <class _Rp, class... _ArgTypes>
+class __value_func<_Rp(_ArgTypes...)> {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ typename aligned_storage<3 * sizeof(void*)>::type __buf_;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+ typedef __base<_Rp(_ArgTypes...)> __func;
+ __func* __f_;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_CFI static __func* __as_base(void* __p) { return reinterpret_cast<__func*>(__p); }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __value_func() _NOEXCEPT : __f_(nullptr) {}
+
+ template <class _Fp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI __value_func(_Fp&& __f, const _Alloc& __a) : __f_(nullptr) {
+ typedef allocator_traits<_Alloc> __alloc_traits;
+ typedef __function::__func<_Fp, _Alloc, _Rp(_ArgTypes...)> _Fun;
+ typedef __rebind_alloc<__alloc_traits, _Fun> _FunAlloc;
+
+ if (__function::__not_null(__f)) {
+ _FunAlloc __af(__a);
+ if (sizeof(_Fun) <= sizeof(__buf_) && is_nothrow_copy_constructible<_Fp>::value &&
+ is_nothrow_copy_constructible<_FunAlloc>::value) {
+ __f_ = ::new ((void*)&__buf_) _Fun(std::move(__f), _Alloc(__af));
+ } else {
+ typedef __allocator_destructor<_FunAlloc> _Dp;
+ unique_ptr<__func, _Dp> __hold(__af.allocate(1), _Dp(__af, 1));
+ ::new ((void*)__hold.get()) _Fun(std::move(__f), _Alloc(__a));
+ __f_ = __hold.release();
+ }
+ }
+ }
+
+ template <class _Fp, __enable_if_t<!is_same<__decay_t<_Fp>, __value_func>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit __value_func(_Fp&& __f) : __value_func(std::forward<_Fp>(__f), allocator<_Fp>()) {}
+
+ _LIBCPP_HIDE_FROM_ABI __value_func(const __value_func& __f) {
+ if (__f.__f_ == nullptr)
+ __f_ = nullptr;
+ else if ((void*)__f.__f_ == &__f.__buf_) {
+ __f_ = __as_base(&__buf_);
+ __f.__f_->__clone(__f_);
+ } else
+ __f_ = __f.__f_->__clone();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __value_func(__value_func&& __f) _NOEXCEPT {
+ if (__f.__f_ == nullptr)
+ __f_ = nullptr;
+ else if ((void*)__f.__f_ == &__f.__buf_) {
+ __f_ = __as_base(&__buf_);
+ __f.__f_->__clone(__f_);
+ } else {
+ __f_ = __f.__f_;
+ __f.__f_ = nullptr;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~__value_func() {
+ if ((void*)__f_ == &__buf_)
+ __f_->destroy();
+ else if (__f_)
+ __f_->destroy_deallocate();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __value_func& operator=(__value_func&& __f) {
+ *this = nullptr;
+ if (__f.__f_ == nullptr)
+ __f_ = nullptr;
+ else if ((void*)__f.__f_ == &__f.__buf_) {
+ __f_ = __as_base(&__buf_);
+ __f.__f_->__clone(__f_);
+ } else {
+ __f_ = __f.__f_;
+ __f.__f_ = nullptr;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __value_func& operator=(nullptr_t) {
+ __func* __f = __f_;
+ __f_ = nullptr;
+ if ((void*)__f == &__buf_)
+ __f->destroy();
+ else if (__f)
+ __f->destroy_deallocate();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Rp operator()(_ArgTypes&&... __args) const {
+ if (__f_ == nullptr)
+ __throw_bad_function_call();
+ return (*__f_)(std::forward<_ArgTypes>(__args)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(__value_func& __f) _NOEXCEPT {
+ if (&__f == this)
+ return;
+ if ((void*)__f_ == &__buf_ && (void*)__f.__f_ == &__f.__buf_) {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ __func* __t = __as_base(&__tempbuf);
+ __f_->__clone(__t);
+ __f_->destroy();
+ __f_ = nullptr;
+ __f.__f_->__clone(__as_base(&__buf_));
+ __f.__f_->destroy();
+ __f.__f_ = nullptr;
+ __f_ = __as_base(&__buf_);
+ __t->__clone(__as_base(&__f.__buf_));
+ __t->destroy();
+ __f.__f_ = __as_base(&__f.__buf_);
+ } else if ((void*)__f_ == &__buf_) {
+ __f_->__clone(__as_base(&__f.__buf_));
+ __f_->destroy();
+ __f_ = __f.__f_;
+ __f.__f_ = __as_base(&__f.__buf_);
+ } else if ((void*)__f.__f_ == &__f.__buf_) {
+ __f.__f_->__clone(__as_base(&__buf_));
+ __f.__f_->destroy();
+ __f.__f_ = __f_;
+ __f_ = __as_base(&__buf_);
+ } else
+ std::swap(__f_, __f.__f_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return __f_ != nullptr; }
+
+# ifndef _LIBCPP_HAS_NO_RTTI
+ _LIBCPP_HIDE_FROM_ABI const std::type_info& target_type() const _NOEXCEPT {
+ if (__f_ == nullptr)
+ return typeid(void);
+ return __f_->target_type();
+ }
+
+ template <typename _Tp>
+ _LIBCPP_HIDE_FROM_ABI const _Tp* target() const _NOEXCEPT {
+ if (__f_ == nullptr)
+ return nullptr;
+ return (const _Tp*)__f_->target(typeid(_Tp));
+ }
+# endif // _LIBCPP_HAS_NO_RTTI
+};
+
+// Storage for a functor object, to be used with __policy to manage copy and
+// destruction.
+union __policy_storage {
+ mutable char __small[sizeof(void*) * 2];
+ void* __large;
+};
+
+// True if _Fun can safely be held in __policy_storage.__small.
+template <typename _Fun>
+struct __use_small_storage
+ : public integral_constant<
+ bool,
+ sizeof(_Fun) <= sizeof(__policy_storage)&& _LIBCPP_ALIGNOF(_Fun) <= _LIBCPP_ALIGNOF(__policy_storage) &&
+ is_trivially_copy_constructible<_Fun>::value && is_trivially_destructible<_Fun>::value> {};
+
+// Policy contains information about how to copy, destroy, and move the
+// underlying functor. You can think of it as a vtable of sorts.
+struct __policy {
+ // Used to copy or destroy __large values. null for trivial objects.
+ void* (*const __clone)(const void*);
+ void (*const __destroy)(void*);
+
+ // True if this is the null policy (no value).
+ const bool __is_null;
+
+ // The target type. May be null if RTTI is disabled.
+ const std::type_info* const __type_info;
+
+ // Returns a pointer to a static policy object suitable for the functor
+ // type.
+ template <typename _Fun>
+ _LIBCPP_HIDE_FROM_ABI static const __policy* __create() {
+ return __choose_policy<_Fun>(__use_small_storage<_Fun>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static const __policy* __create_empty() {
+ static constexpr __policy __policy = {
+ nullptr,
+ nullptr,
+ true,
+# ifndef _LIBCPP_HAS_NO_RTTI
+ &typeid(void)
+# else
+ nullptr
+# endif
+ };
+ return &__policy;
+ }
+
+private:
+ template <typename _Fun>
+ _LIBCPP_HIDE_FROM_ABI static void* __large_clone(const void* __s) {
+ const _Fun* __f = static_cast<const _Fun*>(__s);
+ return __f->__clone();
+ }
+
+ template <typename _Fun>
+ _LIBCPP_HIDE_FROM_ABI static void __large_destroy(void* __s) {
+ _Fun::__destroy_and_delete(static_cast<_Fun*>(__s));
+ }
+
+ template <typename _Fun>
+ _LIBCPP_HIDE_FROM_ABI static const __policy* __choose_policy(/* is_small = */ false_type) {
+ static constexpr __policy __policy = {
+ &__large_clone<_Fun>,
+ &__large_destroy<_Fun>,
+ false,
+# ifndef _LIBCPP_HAS_NO_RTTI
+ &typeid(typename _Fun::_Target)
+# else
+ nullptr
+# endif
+ };
+ return &__policy;
+ }
+
+ template <typename _Fun>
+ _LIBCPP_HIDE_FROM_ABI static const __policy* __choose_policy(/* is_small = */ true_type) {
+ static constexpr __policy __policy = {
+ nullptr,
+ nullptr,
+ false,
+# ifndef _LIBCPP_HAS_NO_RTTI
+ &typeid(typename _Fun::_Target)
+# else
+ nullptr
+# endif
+ };
+ return &__policy;
+ }
+};
+
+// Used to choose between perfect forwarding or pass-by-value. Pass-by-value is
+// faster for types that can be passed in registers.
+template <typename _Tp>
+using __fast_forward = __conditional_t<is_scalar<_Tp>::value, _Tp, _Tp&&>;
+
+// __policy_invoker calls an instance of __alloc_func held in __policy_storage.
+
+template <class _Fp>
+struct __policy_invoker;
+
+template <class _Rp, class... _ArgTypes>
+struct __policy_invoker<_Rp(_ArgTypes...)> {
+ typedef _Rp (*__Call)(const __policy_storage*, __fast_forward<_ArgTypes>...);
+
+ __Call __call_;
+
+ // Creates an invoker that throws bad_function_call.
+ _LIBCPP_HIDE_FROM_ABI __policy_invoker() : __call_(&__call_empty) {}
+
+ // Creates an invoker that calls the given instance of __func.
+ template <typename _Fun>
+ _LIBCPP_HIDE_FROM_ABI static __policy_invoker __create() {
+ return __policy_invoker(&__call_impl<_Fun>);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit __policy_invoker(__Call __c) : __call_(__c) {}
+
+ _LIBCPP_HIDE_FROM_ABI static _Rp __call_empty(const __policy_storage*, __fast_forward<_ArgTypes>...) {
+ __throw_bad_function_call();
+ }
+
+ template <typename _Fun>
+ _LIBCPP_HIDE_FROM_ABI static _Rp __call_impl(const __policy_storage* __buf, __fast_forward<_ArgTypes>... __args) {
+ _Fun* __f = reinterpret_cast<_Fun*>(__use_small_storage<_Fun>::value ? &__buf->__small : __buf->__large);
+ return (*__f)(std::forward<_ArgTypes>(__args)...);
+ }
+};
+
+// __policy_func uses a __policy and __policy_invoker to create a type-erased,
+// copyable functor.
+
+template <class _Fp>
+class __policy_func;
+
+template <class _Rp, class... _ArgTypes>
+class __policy_func<_Rp(_ArgTypes...)> {
+ // Inline storage for small objects.
+ __policy_storage __buf_;
+
+ // Calls the value stored in __buf_. This could technically be part of
+ // policy, but storing it here eliminates a level of indirection inside
+ // operator().
+ typedef __function::__policy_invoker<_Rp(_ArgTypes...)> __invoker;
+ __invoker __invoker_;
+
+ // The policy that describes how to move / copy / destroy __buf_. Never
+ // null, even if the function is empty.
+ const __policy* __policy_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __policy_func() : __policy_(__policy::__create_empty()) {}
+
+ template <class _Fp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI __policy_func(_Fp&& __f, const _Alloc& __a) : __policy_(__policy::__create_empty()) {
+ typedef __alloc_func<_Fp, _Alloc, _Rp(_ArgTypes...)> _Fun;
+ typedef allocator_traits<_Alloc> __alloc_traits;
+ typedef __rebind_alloc<__alloc_traits, _Fun> _FunAlloc;
+
+ if (__function::__not_null(__f)) {
+ __invoker_ = __invoker::template __create<_Fun>();
+ __policy_ = __policy::__create<_Fun>();
+
+ _FunAlloc __af(__a);
+ if (__use_small_storage<_Fun>()) {
+ ::new ((void*)&__buf_.__small) _Fun(std::move(__f), _Alloc(__af));
+ } else {
+ typedef __allocator_destructor<_FunAlloc> _Dp;
+ unique_ptr<_Fun, _Dp> __hold(__af.allocate(1), _Dp(__af, 1));
+ ::new ((void*)__hold.get()) _Fun(std::move(__f), _Alloc(__af));
+ __buf_.__large = __hold.release();
+ }
+ }
+ }
+
+ template <class _Fp, __enable_if_t<!is_same<__decay_t<_Fp>, __policy_func>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit __policy_func(_Fp&& __f) : __policy_(__policy::__create_empty()) {
+ typedef __default_alloc_func<_Fp, _Rp(_ArgTypes...)> _Fun;
+
+ if (__function::__not_null(__f)) {
+ __invoker_ = __invoker::template __create<_Fun>();
+ __policy_ = __policy::__create<_Fun>();
+ if (__use_small_storage<_Fun>()) {
+ ::new ((void*)&__buf_.__small) _Fun(std::move(__f));
+ } else {
+ __builtin_new_allocator::__holder_t __hold = __builtin_new_allocator::__allocate_type<_Fun>(1);
+ __buf_.__large = ::new ((void*)__hold.get()) _Fun(std::move(__f));
+ (void)__hold.release();
+ }
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __policy_func(const __policy_func& __f)
+ : __buf_(__f.__buf_), __invoker_(__f.__invoker_), __policy_(__f.__policy_) {
+ if (__policy_->__clone)
+ __buf_.__large = __policy_->__clone(__f.__buf_.__large);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __policy_func(__policy_func&& __f)
+ : __buf_(__f.__buf_), __invoker_(__f.__invoker_), __policy_(__f.__policy_) {
+ if (__policy_->__destroy) {
+ __f.__policy_ = __policy::__create_empty();
+ __f.__invoker_ = __invoker();
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~__policy_func() {
+ if (__policy_->__destroy)
+ __policy_->__destroy(__buf_.__large);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __policy_func& operator=(__policy_func&& __f) {
+ *this = nullptr;
+ __buf_ = __f.__buf_;
+ __invoker_ = __f.__invoker_;
+ __policy_ = __f.__policy_;
+ __f.__policy_ = __policy::__create_empty();
+ __f.__invoker_ = __invoker();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __policy_func& operator=(nullptr_t) {
+ const __policy* __p = __policy_;
+ __policy_ = __policy::__create_empty();
+ __invoker_ = __invoker();
+ if (__p->__destroy)
+ __p->__destroy(__buf_.__large);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Rp operator()(_ArgTypes&&... __args) const {
+ return __invoker_.__call_(std::addressof(__buf_), std::forward<_ArgTypes>(__args)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(__policy_func& __f) {
+ std::swap(__invoker_, __f.__invoker_);
+ std::swap(__policy_, __f.__policy_);
+ std::swap(__buf_, __f.__buf_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return !__policy_->__is_null; }
+
+# ifndef _LIBCPP_HAS_NO_RTTI
+ _LIBCPP_HIDE_FROM_ABI const std::type_info& target_type() const _NOEXCEPT { return *__policy_->__type_info; }
+
+ template <typename _Tp>
+ _LIBCPP_HIDE_FROM_ABI const _Tp* target() const _NOEXCEPT {
+ if (__policy_->__is_null || typeid(_Tp) != *__policy_->__type_info)
+ return nullptr;
+ if (__policy_->__clone) // Out of line storage.
+ return reinterpret_cast<const _Tp*>(__buf_.__large);
+ else
+ return reinterpret_cast<const _Tp*>(&__buf_.__small);
+ }
+# endif // _LIBCPP_HAS_NO_RTTI
+};
+
+# if defined(_LIBCPP_HAS_BLOCKS_RUNTIME)
+
+extern "C" void* _Block_copy(const void*);
+extern "C" void _Block_release(const void*);
+
+template <class _Rp1, class... _ArgTypes1, class _Alloc, class _Rp, class... _ArgTypes>
+class __func<_Rp1 (^)(_ArgTypes1...), _Alloc, _Rp(_ArgTypes...)> : public __base<_Rp(_ArgTypes...)> {
+ typedef _Rp1 (^__block_type)(_ArgTypes1...);
+ __block_type __f_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __func(__block_type const& __f)
+# ifdef _LIBCPP_HAS_OBJC_ARC
+ : __f_(__f)
+# else
+ : __f_(reinterpret_cast<__block_type>(__f ? _Block_copy(__f) : nullptr))
+# endif
+ {
+ }
+
+ // [TODO] add && to save on a retain
+
+ _LIBCPP_HIDE_FROM_ABI explicit __func(__block_type __f, const _Alloc& /* unused */)
+# ifdef _LIBCPP_HAS_OBJC_ARC
+ : __f_(__f)
+# else
+ : __f_(reinterpret_cast<__block_type>(__f ? _Block_copy(__f) : nullptr))
+# endif
+ {
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual __base<_Rp(_ArgTypes...)>* __clone() const {
+ _LIBCPP_ASSERT_INTERNAL(
+ false,
+ "Block pointers are just pointers, so they should always fit into "
+ "std::function's small buffer optimization. This function should "
+ "never be invoked.");
+ return nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __clone(__base<_Rp(_ArgTypes...)>* __p) const {
+ ::new ((void*)__p) __func(__f_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void destroy() _NOEXCEPT {
+# ifndef _LIBCPP_HAS_OBJC_ARC
+ if (__f_)
+ _Block_release(__f_);
+# endif
+ __f_ = 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void destroy_deallocate() _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(
+ false,
+ "Block pointers are just pointers, so they should always fit into "
+ "std::function's small buffer optimization. This function should "
+ "never be invoked.");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual _Rp operator()(_ArgTypes&&... __arg) {
+ return std::__invoke(__f_, std::forward<_ArgTypes>(__arg)...);
+ }
+
+# ifndef _LIBCPP_HAS_NO_RTTI
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual const void* target(type_info const& __ti) const _NOEXCEPT {
+ if (__ti == typeid(__func::__block_type))
+ return &__f_;
+ return (const void*)nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual const std::type_info& target_type() const _NOEXCEPT {
+ return typeid(__func::__block_type);
+ }
+# endif // _LIBCPP_HAS_NO_RTTI
+};
+
+# endif // _LIBCPP_HAS_EXTENSION_BLOCKS
+
+} // namespace __function
+
+template <class _Rp, class... _ArgTypes>
+class _LIBCPP_TEMPLATE_VIS function<_Rp(_ArgTypes...)>
+ : public __function::__maybe_derive_from_unary_function<_Rp(_ArgTypes...)>,
+ public __function::__maybe_derive_from_binary_function<_Rp(_ArgTypes...)> {
+# ifndef _LIBCPP_ABI_OPTIMIZED_FUNCTION
+ typedef __function::__value_func<_Rp(_ArgTypes...)> __func;
+# else
+ typedef __function::__policy_func<_Rp(_ArgTypes...)> __func;
+# endif
+
+ __func __f_;
+
+ template <class _Fp,
+ bool = _And< _IsNotSame<__remove_cvref_t<_Fp>, function>, __invokable<_Fp, _ArgTypes...> >::value>
+ struct __callable;
+ template <class _Fp>
+ struct __callable<_Fp, true> {
+ static const bool value =
+ is_void<_Rp>::value || __is_core_convertible<typename __invoke_of<_Fp, _ArgTypes...>::type, _Rp>::value;
+ };
+ template <class _Fp>
+ struct __callable<_Fp, false> {
+ static const bool value = false;
+ };
+
+ template <class _Fp>
+ using _EnableIfLValueCallable = __enable_if_t<__callable<_Fp&>::value>;
+
+public:
+ typedef _Rp result_type;
+
+ // construct/copy/destroy:
+ _LIBCPP_HIDE_FROM_ABI function() _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDE_FROM_ABI function(nullptr_t) _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI function(const function&);
+ _LIBCPP_HIDE_FROM_ABI function(function&&) _NOEXCEPT;
+ template <class _Fp, class = _EnableIfLValueCallable<_Fp>>
+ _LIBCPP_HIDE_FROM_ABI function(_Fp);
+
+# if _LIBCPP_STD_VER <= 14
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI function(allocator_arg_t, const _Alloc&) _NOEXCEPT {}
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI function(allocator_arg_t, const _Alloc&, nullptr_t) _NOEXCEPT {}
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI function(allocator_arg_t, const _Alloc&, const function&);
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI function(allocator_arg_t, const _Alloc&, function&&);
+ template <class _Fp, class _Alloc, class = _EnableIfLValueCallable<_Fp>>
+ _LIBCPP_HIDE_FROM_ABI function(allocator_arg_t, const _Alloc& __a, _Fp __f);
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI function& operator=(const function&);
+ _LIBCPP_HIDE_FROM_ABI function& operator=(function&&) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI function& operator=(nullptr_t) _NOEXCEPT;
+ template <class _Fp, class = _EnableIfLValueCallable<__decay_t<_Fp>>>
+ _LIBCPP_HIDE_FROM_ABI function& operator=(_Fp&&);
+
+ _LIBCPP_HIDE_FROM_ABI ~function();
+
+ // function modifiers:
+ _LIBCPP_HIDE_FROM_ABI void swap(function&) _NOEXCEPT;
+
+# if _LIBCPP_STD_VER <= 14
+ template <class _Fp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI void assign(_Fp&& __f, const _Alloc& __a) {
+ function(allocator_arg, __a, std::forward<_Fp>(__f)).swap(*this);
+ }
+# endif
+
+ // function capacity:
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return static_cast<bool>(__f_); }
+
+ // deleted overloads close possible hole in the type system
+ template <class _R2, class... _ArgTypes2>
+ bool operator==(const function<_R2(_ArgTypes2...)>&) const = delete;
+# if _LIBCPP_STD_VER <= 17
+ template <class _R2, class... _ArgTypes2>
+ bool operator!=(const function<_R2(_ArgTypes2...)>&) const = delete;
+# endif
+
+public:
+ // function invocation:
+ _LIBCPP_HIDE_FROM_ABI _Rp operator()(_ArgTypes...) const;
+
+# ifndef _LIBCPP_HAS_NO_RTTI
+ // function target access:
+ _LIBCPP_HIDE_FROM_ABI const std::type_info& target_type() const _NOEXCEPT;
+ template <typename _Tp>
+ _LIBCPP_HIDE_FROM_ABI _Tp* target() _NOEXCEPT;
+ template <typename _Tp>
+ _LIBCPP_HIDE_FROM_ABI const _Tp* target() const _NOEXCEPT;
+# endif // _LIBCPP_HAS_NO_RTTI
+};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Rp, class... _Ap>
+function(_Rp (*)(_Ap...)) -> function<_Rp(_Ap...)>;
+
+template <class _Fp, class _Stripped = typename __strip_signature<decltype(&_Fp::operator())>::type>
+function(_Fp) -> function<_Stripped>;
+# endif // _LIBCPP_STD_VER >= 17
+
+template <class _Rp, class... _ArgTypes>
+function<_Rp(_ArgTypes...)>::function(const function& __f) : __f_(__f.__f_) {}
+
+# if _LIBCPP_STD_VER <= 14
+template <class _Rp, class... _ArgTypes>
+template <class _Alloc>
+function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&, const function& __f) : __f_(__f.__f_) {}
+# endif
+
+template <class _Rp, class... _ArgTypes>
+function<_Rp(_ArgTypes...)>::function(function&& __f) _NOEXCEPT : __f_(std::move(__f.__f_)) {}
+
+# if _LIBCPP_STD_VER <= 14
+template <class _Rp, class... _ArgTypes>
+template <class _Alloc>
+function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&, function&& __f) : __f_(std::move(__f.__f_)) {}
+# endif
+
+template <class _Rp, class... _ArgTypes>
+template <class _Fp, class>
+function<_Rp(_ArgTypes...)>::function(_Fp __f) : __f_(std::move(__f)) {}
+
+# if _LIBCPP_STD_VER <= 14
+template <class _Rp, class... _ArgTypes>
+template <class _Fp, class _Alloc, class>
+function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc& __a, _Fp __f) : __f_(std::move(__f), __a) {}
+# endif
+
+template <class _Rp, class... _ArgTypes>
+function<_Rp(_ArgTypes...)>& function<_Rp(_ArgTypes...)>::operator=(const function& __f) {
+ function(__f).swap(*this);
+ return *this;
+}
+
+template <class _Rp, class... _ArgTypes>
+function<_Rp(_ArgTypes...)>& function<_Rp(_ArgTypes...)>::operator=(function&& __f) _NOEXCEPT {
+ __f_ = std::move(__f.__f_);
+ return *this;
+}
+
+template <class _Rp, class... _ArgTypes>
+function<_Rp(_ArgTypes...)>& function<_Rp(_ArgTypes...)>::operator=(nullptr_t) _NOEXCEPT {
+ __f_ = nullptr;
+ return *this;
+}
+
+template <class _Rp, class... _ArgTypes>
+template <class _Fp, class>
+function<_Rp(_ArgTypes...)>& function<_Rp(_ArgTypes...)>::operator=(_Fp&& __f) {
+ function(std::forward<_Fp>(__f)).swap(*this);
+ return *this;
+}
+
+template <class _Rp, class... _ArgTypes>
+function<_Rp(_ArgTypes...)>::~function() {}
+
+template <class _Rp, class... _ArgTypes>
+void function<_Rp(_ArgTypes...)>::swap(function& __f) _NOEXCEPT {
+ __f_.swap(__f.__f_);
+}
+
+template <class _Rp, class... _ArgTypes>
+_Rp function<_Rp(_ArgTypes...)>::operator()(_ArgTypes... __arg) const {
+ return __f_(std::forward<_ArgTypes>(__arg)...);
+}
+
+# ifndef _LIBCPP_HAS_NO_RTTI
+
+template <class _Rp, class... _ArgTypes>
+const std::type_info& function<_Rp(_ArgTypes...)>::target_type() const _NOEXCEPT {
+ return __f_.target_type();
+}
+
+template <class _Rp, class... _ArgTypes>
+template <typename _Tp>
+_Tp* function<_Rp(_ArgTypes...)>::target() _NOEXCEPT {
+ return (_Tp*)(__f_.template target<_Tp>());
+}
+
+template <class _Rp, class... _ArgTypes>
+template <typename _Tp>
+const _Tp* function<_Rp(_ArgTypes...)>::target() const _NOEXCEPT {
+ return __f_.template target<_Tp>();
+}
+
+# endif // _LIBCPP_HAS_NO_RTTI
+
+template <class _Rp, class... _ArgTypes>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) _NOEXCEPT {
+ return !__f;
+}
+
+# if _LIBCPP_STD_VER <= 17
+
+template <class _Rp, class... _ArgTypes>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) _NOEXCEPT {
+ return !__f;
+}
+
+template <class _Rp, class... _ArgTypes>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) _NOEXCEPT {
+ return (bool)__f;
+}
+
+template <class _Rp, class... _ArgTypes>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) _NOEXCEPT {
+ return (bool)__f;
+}
+
+# endif // _LIBCPP_STD_VER <= 17
+
+template <class _Rp, class... _ArgTypes>
+inline _LIBCPP_HIDE_FROM_ABI void swap(function<_Rp(_ArgTypes...)>& __x, function<_Rp(_ArgTypes...)>& __y) _NOEXCEPT {
+ return __x.swap(__y);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FUNCTIONAL_FUNCTION_H
diff --git a/libcxx/include/__cxx03/__functional/hash.h b/libcxx/include/__cxx03/__functional/hash.h
new file mode 100644
index 00000000000000..a9e450edd39f53
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/hash.h
@@ -0,0 +1,542 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_HASH_H
+#define _LIBCPP___FUNCTIONAL_HASH_H
+
+#include <__config>
+#include <__functional/unary_function.h>
+#include <__fwd/functional.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_enum.h>
+#include <__type_traits/underlying_type.h>
+#include <__utility/pair.h>
+#include <__utility/swap.h>
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Size>
+inline _LIBCPP_HIDE_FROM_ABI _Size __loadword(const void* __p) {
+ _Size __r;
+ std::memcpy(&__r, __p, sizeof(__r));
+ return __r;
+}
+
+// We use murmur2 when size_t is 32 bits, and cityhash64 when size_t
+// is 64 bits. This is because cityhash64 uses 64bit x 64bit
+// multiplication, which can be very slow on 32-bit systems.
+template <class _Size, size_t = sizeof(_Size) * __CHAR_BIT__>
+struct __murmur2_or_cityhash;
+
+template <class _Size>
+struct __murmur2_or_cityhash<_Size, 32> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK _Size
+ operator()(const void* __key, _Size __len) const {
+ // murmur2
+ const _Size __m = 0x5bd1e995;
+ const _Size __r = 24;
+ _Size __h = __len;
+ const unsigned char* __data = static_cast<const unsigned char*>(__key);
+ for (; __len >= 4; __data += 4, __len -= 4) {
+ _Size __k = std::__loadword<_Size>(__data);
+ __k *= __m;
+ __k ^= __k >> __r;
+ __k *= __m;
+ __h *= __m;
+ __h ^= __k;
+ }
+ switch (__len) {
+ case 3:
+ __h ^= static_cast<_Size>(__data[2] << 16);
+ _LIBCPP_FALLTHROUGH();
+ case 2:
+ __h ^= static_cast<_Size>(__data[1] << 8);
+ _LIBCPP_FALLTHROUGH();
+ case 1:
+ __h ^= __data[0];
+ __h *= __m;
+ }
+ __h ^= __h >> 13;
+ __h *= __m;
+ __h ^= __h >> 15;
+ return __h;
+ }
+};
+
+template <class _Size>
+struct __murmur2_or_cityhash<_Size, 64> {
+ // cityhash64
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK _Size
+ operator()(const void* __key, _Size __len) const {
+ const char* __s = static_cast<const char*>(__key);
+ if (__len <= 32) {
+ if (__len <= 16) {
+ return __hash_len_0_to_16(__s, __len);
+ } else {
+ return __hash_len_17_to_32(__s, __len);
+ }
+ } else if (__len <= 64) {
+ return __hash_len_33_to_64(__s, __len);
+ }
+
+ // For strings over 64 bytes we hash the end first, and then as we
+ // loop we keep 56 bytes of state: v, w, x, y, and z.
+ _Size __x = std::__loadword<_Size>(__s + __len - 40);
+ _Size __y = std::__loadword<_Size>(__s + __len - 16) + std::__loadword<_Size>(__s + __len - 56);
+ _Size __z =
+ __hash_len_16(std::__loadword<_Size>(__s + __len - 48) + __len, std::__loadword<_Size>(__s + __len - 24));
+ pair<_Size, _Size> __v = __weak_hash_len_32_with_seeds(__s + __len - 64, __len, __z);
+ pair<_Size, _Size> __w = __weak_hash_len_32_with_seeds(__s + __len - 32, __y + __k1, __x);
+ __x = __x * __k1 + std::__loadword<_Size>(__s);
+
+ // Decrease len to the nearest multiple of 64, and operate on 64-byte chunks.
+ __len = (__len - 1) & ~static_cast<_Size>(63);
+ do {
+ __x = __rotate(__x + __y + __v.first + std::__loadword<_Size>(__s + 8), 37) * __k1;
+ __y = __rotate(__y + __v.second + std::__loadword<_Size>(__s + 48), 42) * __k1;
+ __x ^= __w.second;
+ __y += __v.first + std::__loadword<_Size>(__s + 40);
+ __z = __rotate(__z + __w.first, 33) * __k1;
+ __v = __weak_hash_len_32_with_seeds(__s, __v.second * __k1, __x + __w.first);
+ __w = __weak_hash_len_32_with_seeds(__s + 32, __z + __w.second, __y + std::__loadword<_Size>(__s + 16));
+ std::swap(__z, __x);
+ __s += 64;
+ __len -= 64;
+ } while (__len != 0);
+ return __hash_len_16(__hash_len_16(__v.first, __w.first) + __shift_mix(__y) * __k1 + __z,
+ __hash_len_16(__v.second, __w.second) + __x);
+ }
+
+private:
+ // Some primes between 2^63 and 2^64.
+ static const _Size __k0 = 0xc3a5c85c97cb3127ULL;
+ static const _Size __k1 = 0xb492b66fbe98f273ULL;
+ static const _Size __k2 = 0x9ae16a3b2f90404fULL;
+ static const _Size __k3 = 0xc949d7c7509e6557ULL;
+
+ _LIBCPP_HIDE_FROM_ABI static _Size __rotate(_Size __val, int __shift) {
+ return __shift == 0 ? __val : ((__val >> __shift) | (__val << (64 - __shift)));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _Size __rotate_by_at_least_1(_Size __val, int __shift) {
+ return (__val >> __shift) | (__val << (64 - __shift));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _Size __shift_mix(_Size __val) { return __val ^ (__val >> 47); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK static _Size __hash_len_16(_Size __u, _Size __v) {
+ const _Size __mul = 0x9ddfea08eb382d69ULL;
+ _Size __a = (__u ^ __v) * __mul;
+ __a ^= (__a >> 47);
+ _Size __b = (__v ^ __a) * __mul;
+ __b ^= (__b >> 47);
+ __b *= __mul;
+ return __b;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK static _Size
+ __hash_len_0_to_16(const char* __s, _Size __len) {
+ if (__len > 8) {
+ const _Size __a = std::__loadword<_Size>(__s);
+ const _Size __b = std::__loadword<_Size>(__s + __len - 8);
+ return __hash_len_16(__a, __rotate_by_at_least_1(__b + __len, __len)) ^ __b;
+ }
+ if (__len >= 4) {
+ const uint32_t __a = std::__loadword<uint32_t>(__s);
+ const uint32_t __b = std::__loadword<uint32_t>(__s + __len - 4);
+#ifdef _LIBCPP_ABI_FIX_CITYHASH_IMPLEMENTATION
+ return __hash_len_16(__len + (static_cast<_Size>(__a) << 3), __b);
+#else
+ return __hash_len_16(__len + (__a << 3), __b);
+#endif
+ }
+ if (__len > 0) {
+ const unsigned char __a = static_cast<unsigned char>(__s[0]);
+ const unsigned char __b = static_cast<unsigned char>(__s[__len >> 1]);
+ const unsigned char __c = static_cast<unsigned char>(__s[__len - 1]);
+ const uint32_t __y = static_cast<uint32_t>(__a) + (static_cast<uint32_t>(__b) << 8);
+ const uint32_t __z = __len + (static_cast<uint32_t>(__c) << 2);
+ return __shift_mix(__y * __k2 ^ __z * __k3) * __k2;
+ }
+ return __k2;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK static _Size
+ __hash_len_17_to_32(const char* __s, _Size __len) {
+ const _Size __a = std::__loadword<_Size>(__s) * __k1;
+ const _Size __b = std::__loadword<_Size>(__s + 8);
+ const _Size __c = std::__loadword<_Size>(__s + __len - 8) * __k2;
+ const _Size __d = std::__loadword<_Size>(__s + __len - 16) * __k0;
+ return __hash_len_16(
+ __rotate(__a - __b, 43) + __rotate(__c, 30) + __d, __a + __rotate(__b ^ __k3, 20) - __c + __len);
+ }
+
+ // Return a 16-byte hash for 48 bytes. Quick and dirty.
+ // Callers do best to use "random-looking" values for a and b.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK static pair<_Size, _Size>
+ __weak_hash_len_32_with_seeds(_Size __w, _Size __x, _Size __y, _Size __z, _Size __a, _Size __b) {
+ __a += __w;
+ __b = __rotate(__b + __a + __z, 21);
+ const _Size __c = __a;
+ __a += __x;
+ __a += __y;
+ __b += __rotate(__a, 44);
+ return pair<_Size, _Size>(__a + __z, __b + __c);
+ }
+
+ // Return a 16-byte hash for s[0] ... s[31], a, and b. Quick and dirty.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK static pair<_Size, _Size>
+ __weak_hash_len_32_with_seeds(const char* __s, _Size __a, _Size __b) {
+ return __weak_hash_len_32_with_seeds(
+ std::__loadword<_Size>(__s),
+ std::__loadword<_Size>(__s + 8),
+ std::__loadword<_Size>(__s + 16),
+ std::__loadword<_Size>(__s + 24),
+ __a,
+ __b);
+ }
+
+ // Return an 8-byte hash for 33 to 64 bytes.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK static _Size
+ __hash_len_33_to_64(const char* __s, size_t __len) {
+ _Size __z = std::__loadword<_Size>(__s + 24);
+ _Size __a = std::__loadword<_Size>(__s) + (__len + std::__loadword<_Size>(__s + __len - 16)) * __k0;
+ _Size __b = __rotate(__a + __z, 52);
+ _Size __c = __rotate(__a, 37);
+ __a += std::__loadword<_Size>(__s + 8);
+ __c += __rotate(__a, 7);
+ __a += std::__loadword<_Size>(__s + 16);
+ _Size __vf = __a + __z;
+ _Size __vs = __b + __rotate(__a, 31) + __c;
+ __a = std::__loadword<_Size>(__s + 16) + std::__loadword<_Size>(__s + __len - 32);
+ __z += std::__loadword<_Size>(__s + __len - 8);
+ __b = __rotate(__a + __z, 52);
+ __c = __rotate(__a, 37);
+ __a += std::__loadword<_Size>(__s + __len - 24);
+ __c += __rotate(__a, 7);
+ __a += std::__loadword<_Size>(__s + __len - 16);
+ _Size __wf = __a + __z;
+ _Size __ws = __b + __rotate(__a, 31) + __c;
+ _Size __r = __shift_mix((__vf + __ws) * __k2 + (__wf + __vs) * __k0);
+ return __shift_mix(__r * __k0 + __vs) * __k2;
+ }
+};
+
+template <class _Tp, size_t = sizeof(_Tp) / sizeof(size_t)>
+struct __scalar_hash;
+
+template <class _Tp>
+struct __scalar_hash<_Tp, 0> : public __unary_function<_Tp, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT {
+ union {
+ _Tp __t;
+ size_t __a;
+ } __u;
+ __u.__a = 0;
+ __u.__t = __v;
+ return __u.__a;
+ }
+};
+
+template <class _Tp>
+struct __scalar_hash<_Tp, 1> : public __unary_function<_Tp, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT {
+ union {
+ _Tp __t;
+ size_t __a;
+ } __u;
+ __u.__t = __v;
+ return __u.__a;
+ }
+};
+
+template <class _Tp>
+struct __scalar_hash<_Tp, 2> : public __unary_function<_Tp, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT {
+ union {
+ _Tp __t;
+ struct {
+ size_t __a;
+ size_t __b;
+ } __s;
+ } __u;
+ __u.__t = __v;
+ return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
+ }
+};
+
+template <class _Tp>
+struct __scalar_hash<_Tp, 3> : public __unary_function<_Tp, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT {
+ union {
+ _Tp __t;
+ struct {
+ size_t __a;
+ size_t __b;
+ size_t __c;
+ } __s;
+ } __u;
+ __u.__t = __v;
+ return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
+ }
+};
+
+template <class _Tp>
+struct __scalar_hash<_Tp, 4> : public __unary_function<_Tp, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT {
+ union {
+ _Tp __t;
+ struct {
+ size_t __a;
+ size_t __b;
+ size_t __c;
+ size_t __d;
+ } __s;
+ } __u;
+ __u.__t = __v;
+ return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
+ }
+};
+
+struct _PairT {
+ size_t first;
+ size_t second;
+};
+
+_LIBCPP_HIDE_FROM_ABI inline size_t __hash_combine(size_t __lhs, size_t __rhs) _NOEXCEPT {
+ typedef __scalar_hash<_PairT> _HashT;
+ const _PairT __p = {__lhs, __rhs};
+ return _HashT()(__p);
+}
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS hash<_Tp*> : public __unary_function<_Tp*, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp* __v) const _NOEXCEPT {
+ union {
+ _Tp* __t;
+ size_t __a;
+ } __u;
+ __u.__t = __v;
+ return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
+ }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<bool> : public __unary_function<bool, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(bool __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<char> : public __unary_function<char, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(char __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<signed char> : public __unary_function<signed char, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(signed char __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned char> : public __unary_function<unsigned char, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(unsigned char __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<char8_t> : public __unary_function<char8_t, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(char8_t __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+#endif // !_LIBCPP_HAS_NO_CHAR8_T
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<char16_t> : public __unary_function<char16_t, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(char16_t __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<char32_t> : public __unary_function<char32_t, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(char32_t __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<wchar_t> : public __unary_function<wchar_t, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(wchar_t __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<short> : public __unary_function<short, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(short __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned short> : public __unary_function<unsigned short, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(unsigned short __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<int> : public __unary_function<int, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(int __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned int> : public __unary_function<unsigned int, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(unsigned int __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<long> : public __unary_function<long, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(long __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned long> : public __unary_function<unsigned long, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(unsigned long __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<long long> : public __scalar_hash<long long> {};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned long long> : public __scalar_hash<unsigned long long> {};
+
+#ifndef _LIBCPP_HAS_NO_INT128
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<__int128_t> : public __scalar_hash<__int128_t> {};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<__uint128_t> : public __scalar_hash<__uint128_t> {};
+
+#endif
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<float> : public __scalar_hash<float> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(float __v) const _NOEXCEPT {
+ // -0.0 and 0.0 should return same hash
+ if (__v == 0.0f)
+ return 0;
+ return __scalar_hash<float>::operator()(__v);
+ }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<double> : public __scalar_hash<double> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(double __v) const _NOEXCEPT {
+ // -0.0 and 0.0 should return same hash
+ if (__v == 0.0)
+ return 0;
+ return __scalar_hash<double>::operator()(__v);
+ }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<long double> : public __scalar_hash<long double> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(long double __v) const _NOEXCEPT {
+ // -0.0 and 0.0 should return same hash
+ if (__v == 0.0L)
+ return 0;
+#if defined(__i386__) || (defined(__x86_64__) && defined(__ILP32__))
+ // Zero out padding bits
+ union {
+ long double __t;
+ struct {
+ size_t __a;
+ size_t __b;
+ size_t __c;
+ size_t __d;
+ } __s;
+ } __u;
+ __u.__s.__a = 0;
+ __u.__s.__b = 0;
+ __u.__s.__c = 0;
+ __u.__s.__d = 0;
+ __u.__t = __v;
+ return __u.__s.__a ^ __u.__s.__b ^ __u.__s.__c ^ __u.__s.__d;
+#elif defined(__x86_64__)
+ // Zero out padding bits
+ union {
+ long double __t;
+ struct {
+ size_t __a;
+ size_t __b;
+ } __s;
+ } __u;
+ __u.__s.__a = 0;
+ __u.__s.__b = 0;
+ __u.__t = __v;
+ return __u.__s.__a ^ __u.__s.__b;
+#else
+ return __scalar_hash<long double>::operator()(__v);
+#endif
+ }
+};
+
+template <class _Tp, bool = is_enum<_Tp>::value>
+struct _LIBCPP_TEMPLATE_VIS __enum_hash : public __unary_function<_Tp, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT {
+ typedef typename underlying_type<_Tp>::type type;
+ return hash<type>()(static_cast<type>(__v));
+ }
+};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS __enum_hash<_Tp, false> {
+ __enum_hash() = delete;
+ __enum_hash(__enum_hash const&) = delete;
+ __enum_hash& operator=(__enum_hash const&) = delete;
+};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS hash : public __enum_hash<_Tp> {};
+
+#if _LIBCPP_STD_VER >= 17
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<nullptr_t> : public __unary_function<nullptr_t, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(nullptr_t) const _NOEXCEPT { return 662607004ull; }
+};
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Key, class _Hash>
+using __check_hash_requirements _LIBCPP_NODEBUG =
+ integral_constant<bool,
+ is_copy_constructible<_Hash>::value && is_move_constructible<_Hash>::value &&
+ __invokable_r<size_t, _Hash, _Key const&>::value >;
+
+template <class _Key, class _Hash = hash<_Key> >
+using __has_enabled_hash _LIBCPP_NODEBUG =
+ integral_constant<bool, __check_hash_requirements<_Key, _Hash>::value && is_default_constructible<_Hash>::value >;
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Type, class>
+using __enable_hash_helper_imp _LIBCPP_NODEBUG = _Type;
+
+template <class _Type, class... _Keys>
+using __enable_hash_helper _LIBCPP_NODEBUG =
+ __enable_hash_helper_imp<_Type, __enable_if_t<__all<__has_enabled_hash<_Keys>::value...>::value> >;
+# else
+template <class _Type, class...>
+using __enable_hash_helper _LIBCPP_NODEBUG = _Type;
+# endif
+
+#endif // !_LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_HASH_H
diff --git a/libcxx/include/__cxx03/__functional/identity.h b/libcxx/include/__cxx03/__functional/identity.h
new file mode 100644
index 00000000000000..8468de3dae26c2
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/identity.h
@@ -0,0 +1,65 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_IDENTITY_H
+#define _LIBCPP___FUNCTIONAL_IDENTITY_H
+
+#include <__config>
+#include <__fwd/functional.h>
+#include <__type_traits/integral_constant.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __is_identity : false_type {};
+
+struct __identity {
+ template <class _Tp>
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp&& operator()(_Tp&& __t) const _NOEXCEPT {
+ return std::forward<_Tp>(__t);
+ }
+
+ using is_transparent = void;
+};
+
+template <>
+struct __is_identity<__identity> : true_type {};
+template <>
+struct __is_identity<reference_wrapper<__identity> > : true_type {};
+template <>
+struct __is_identity<reference_wrapper<const __identity> > : true_type {};
+
+#if _LIBCPP_STD_VER >= 20
+
+struct identity {
+ template <class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp&& operator()(_Tp&& __t) const noexcept {
+ return std::forward<_Tp>(__t);
+ }
+
+ using is_transparent = void;
+};
+
+template <>
+struct __is_identity<identity> : true_type {};
+template <>
+struct __is_identity<reference_wrapper<identity> > : true_type {};
+template <>
+struct __is_identity<reference_wrapper<const identity> > : true_type {};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_IDENTITY_H
diff --git a/libcxx/include/__cxx03/__functional/invoke.h b/libcxx/include/__cxx03/__functional/invoke.h
new file mode 100644
index 00000000000000..ef4bf25f07759f
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/invoke.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_INVOKE_H
+#define _LIBCPP___FUNCTIONAL_INVOKE_H
+
+#include <__config>
+#include <__type_traits/invoke.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Fn, class... _Args>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 invoke_result_t<_Fn, _Args...>
+invoke(_Fn&& __f, _Args&&... __args) noexcept(is_nothrow_invocable_v<_Fn, _Args...>) {
+ return std::__invoke(std::forward<_Fn>(__f), std::forward<_Args>(__args)...);
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#if _LIBCPP_STD_VER >= 23
+template <class _Result, class _Fn, class... _Args>
+ requires is_invocable_r_v<_Result, _Fn, _Args...>
+_LIBCPP_HIDE_FROM_ABI constexpr _Result
+invoke_r(_Fn&& __f, _Args&&... __args) noexcept(is_nothrow_invocable_r_v<_Result, _Fn, _Args...>) {
+ if constexpr (is_void_v<_Result>) {
+ static_cast<void>(std::invoke(std::forward<_Fn>(__f), std::forward<_Args>(__args)...));
+ } else {
+ // TODO: Use reference_converts_from_temporary_v once implemented
+ // using _ImplicitInvokeResult = invoke_result_t<_Fn, _Args...>;
+ // static_assert(!reference_converts_from_temporary_v<_Result, _ImplicitInvokeResult>,
+ static_assert(true,
+ "Returning from invoke_r would bind a temporary object to the reference return type, "
+ "which would result in a dangling reference.");
+ return std::invoke(std::forward<_Fn>(__f), std::forward<_Args>(__args)...);
+ }
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_INVOKE_H
diff --git a/libcxx/include/__cxx03/__functional/is_transparent.h b/libcxx/include/__cxx03/__functional/is_transparent.h
new file mode 100644
index 00000000000000..b2d62f2e3ead84
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/is_transparent.h
@@ -0,0 +1,34 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_IS_TRANSPARENT
+#define _LIBCPP___FUNCTIONAL_IS_TRANSPARENT
+
+#include <__config>
+#include <__type_traits/void_t.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 14
+
+template <class _Tp, class, class = void>
+inline const bool __is_transparent_v = false;
+
+template <class _Tp, class _Up>
+inline const bool __is_transparent_v<_Tp, _Up, __void_t<typename _Tp::is_transparent> > = true;
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_IS_TRANSPARENT
diff --git a/libcxx/include/__cxx03/__functional/mem_fn.h b/libcxx/include/__cxx03/__functional/mem_fn.h
new file mode 100644
index 00000000000000..ee07a71774f9a9
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/mem_fn.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_MEM_FN_H
+#define _LIBCPP___FUNCTIONAL_MEM_FN_H
+
+#include <__config>
+#include <__functional/binary_function.h>
+#include <__functional/invoke.h>
+#include <__functional/weak_result_type.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+class __mem_fn : public __weak_result_type<_Tp> {
+public:
+ // types
+ typedef _Tp type;
+
+private:
+ type __f_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __mem_fn(type __f) _NOEXCEPT : __f_(__f) {}
+
+ // invoke
+ template <class... _ArgTypes>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+
+ typename __invoke_return<type, _ArgTypes...>::type
+ operator()(_ArgTypes&&... __args) const {
+ return std::__invoke(__f_, std::forward<_ArgTypes>(__args)...);
+ }
+};
+
+template <class _Rp, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __mem_fn<_Rp _Tp::*> mem_fn(_Rp _Tp::*__pm) _NOEXCEPT {
+ return __mem_fn<_Rp _Tp::*>(__pm);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_MEM_FN_H
diff --git a/libcxx/include/__cxx03/__functional/mem_fun_ref.h b/libcxx/include/__cxx03/__functional/mem_fun_ref.h
new file mode 100644
index 00000000000000..c344420b0299e0
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/mem_fun_ref.h
@@ -0,0 +1,146 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_MEM_FUN_REF_H
+#define _LIBCPP___FUNCTIONAL_MEM_FUN_REF_H
+
+#include <__config>
+#include <__functional/binary_function.h>
+#include <__functional/unary_function.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+template <class _Sp, class _Tp>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 mem_fun_t : public __unary_function<_Tp*, _Sp> {
+ _Sp (_Tp::*__p_)();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit mem_fun_t(_Sp (_Tp::*__p)()) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI _Sp operator()(_Tp* __p) const { return (__p->*__p_)(); }
+};
+
+template <class _Sp, class _Tp, class _Ap>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 mem_fun1_t : public __binary_function<_Tp*, _Ap, _Sp> {
+ _Sp (_Tp::*__p_)(_Ap);
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit mem_fun1_t(_Sp (_Tp::*__p)(_Ap)) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI _Sp operator()(_Tp* __p, _Ap __x) const { return (__p->*__p_)(__x); }
+};
+
+template <class _Sp, class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI mem_fun_t<_Sp, _Tp> mem_fun(_Sp (_Tp::*__f)()) {
+ return mem_fun_t<_Sp, _Tp>(__f);
+}
+
+template <class _Sp, class _Tp, class _Ap>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI mem_fun1_t<_Sp, _Tp, _Ap> mem_fun(_Sp (_Tp::*__f)(_Ap)) {
+ return mem_fun1_t<_Sp, _Tp, _Ap>(__f);
+}
+
+template <class _Sp, class _Tp>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 mem_fun_ref_t : public __unary_function<_Tp, _Sp> {
+ _Sp (_Tp::*__p_)();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit mem_fun_ref_t(_Sp (_Tp::*__p)()) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI _Sp operator()(_Tp& __p) const { return (__p.*__p_)(); }
+};
+
+template <class _Sp, class _Tp, class _Ap>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 mem_fun1_ref_t : public __binary_function<_Tp, _Ap, _Sp> {
+ _Sp (_Tp::*__p_)(_Ap);
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit mem_fun1_ref_t(_Sp (_Tp::*__p)(_Ap)) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI _Sp operator()(_Tp& __p, _Ap __x) const { return (__p.*__p_)(__x); }
+};
+
+template <class _Sp, class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI mem_fun_ref_t<_Sp, _Tp> mem_fun_ref(_Sp (_Tp::*__f)()) {
+ return mem_fun_ref_t<_Sp, _Tp>(__f);
+}
+
+template <class _Sp, class _Tp, class _Ap>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI mem_fun1_ref_t<_Sp, _Tp, _Ap>
+mem_fun_ref(_Sp (_Tp::*__f)(_Ap)) {
+ return mem_fun1_ref_t<_Sp, _Tp, _Ap>(__f);
+}
+
+template <class _Sp, class _Tp>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 const_mem_fun_t : public __unary_function<const _Tp*, _Sp> {
+ _Sp (_Tp::*__p_)() const;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit const_mem_fun_t(_Sp (_Tp::*__p)() const) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI _Sp operator()(const _Tp* __p) const { return (__p->*__p_)(); }
+};
+
+template <class _Sp, class _Tp, class _Ap>
+class _LIBCPP_TEMPLATE_VIS
+_LIBCPP_DEPRECATED_IN_CXX11 const_mem_fun1_t : public __binary_function<const _Tp*, _Ap, _Sp> {
+ _Sp (_Tp::*__p_)(_Ap) const;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit const_mem_fun1_t(_Sp (_Tp::*__p)(_Ap) const) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI _Sp operator()(const _Tp* __p, _Ap __x) const { return (__p->*__p_)(__x); }
+};
+
+template <class _Sp, class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI const_mem_fun_t<_Sp, _Tp> mem_fun(_Sp (_Tp::*__f)() const) {
+ return const_mem_fun_t<_Sp, _Tp>(__f);
+}
+
+template <class _Sp, class _Tp, class _Ap>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI const_mem_fun1_t<_Sp, _Tp, _Ap>
+mem_fun(_Sp (_Tp::*__f)(_Ap) const) {
+ return const_mem_fun1_t<_Sp, _Tp, _Ap>(__f);
+}
+
+template <class _Sp, class _Tp>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 const_mem_fun_ref_t : public __unary_function<_Tp, _Sp> {
+ _Sp (_Tp::*__p_)() const;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit const_mem_fun_ref_t(_Sp (_Tp::*__p)() const) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI _Sp operator()(const _Tp& __p) const { return (__p.*__p_)(); }
+};
+
+template <class _Sp, class _Tp, class _Ap>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 const_mem_fun1_ref_t : public __binary_function<_Tp, _Ap, _Sp> {
+ _Sp (_Tp::*__p_)(_Ap) const;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit const_mem_fun1_ref_t(_Sp (_Tp::*__p)(_Ap) const) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI _Sp operator()(const _Tp& __p, _Ap __x) const { return (__p.*__p_)(__x); }
+};
+
+template <class _Sp, class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI const_mem_fun_ref_t<_Sp, _Tp>
+mem_fun_ref(_Sp (_Tp::*__f)() const) {
+ return const_mem_fun_ref_t<_Sp, _Tp>(__f);
+}
+
+template <class _Sp, class _Tp, class _Ap>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI const_mem_fun1_ref_t<_Sp, _Tp, _Ap>
+mem_fun_ref(_Sp (_Tp::*__f)(_Ap) const) {
+ return const_mem_fun1_ref_t<_Sp, _Tp, _Ap>(__f);
+}
+
+#endif // _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_MEM_FUN_REF_H
diff --git a/libcxx/include/__cxx03/__functional/not_fn.h b/libcxx/include/__cxx03/__functional/not_fn.h
new file mode 100644
index 00000000000000..4b3ce5524a7434
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/not_fn.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_NOT_FN_H
+#define _LIBCPP___FUNCTIONAL_NOT_FN_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__functional/perfect_forward.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+struct __not_fn_op {
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 auto operator()(_Args&&... __args) const
+ noexcept(noexcept(!std::invoke(std::forward<_Args>(__args)...)))
+ -> decltype(!std::invoke(std::forward<_Args>(__args)...)) {
+ return !std::invoke(std::forward<_Args>(__args)...);
+ }
+};
+
+template <class _Fn>
+struct __not_fn_t : __perfect_forward<__not_fn_op, _Fn> {
+ using __perfect_forward<__not_fn_op, _Fn>::__perfect_forward;
+};
+
+template <class _Fn,
+ class = enable_if_t< is_constructible_v<decay_t<_Fn>, _Fn> && is_move_constructible_v<decay_t<_Fn>> >>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 auto not_fn(_Fn&& __f) {
+ return __not_fn_t<decay_t<_Fn>>(std::forward<_Fn>(__f));
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_NOT_FN_H
diff --git a/libcxx/include/__cxx03/__functional/operations.h b/libcxx/include/__cxx03/__functional/operations.h
new file mode 100644
index 00000000000000..0a6320f19de3f3
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/operations.h
@@ -0,0 +1,541 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_OPERATIONS_H
+#define _LIBCPP___FUNCTIONAL_OPERATIONS_H
+
+#include <__config>
+#include <__functional/binary_function.h>
+#include <__functional/unary_function.h>
+#include <__type_traits/desugars_to.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Arithmetic operations
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS plus : __binary_function<_Tp, _Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x + __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(plus);
+
+// The non-transparent std::plus specialization is only equivalent to a raw plus
+// operator when we don't perform an implicit conversion when calling it.
+template <class _Tp>
+inline const bool __desugars_to_v<__plus_tag, plus<_Tp>, _Tp, _Tp> = true;
+
+template <class _Tp, class _Up>
+inline const bool __desugars_to_v<__plus_tag, plus<void>, _Tp, _Up> = true;
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS plus<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) + std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) + std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) + std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS minus : __binary_function<_Tp, _Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x - __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(minus);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS minus<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) - std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) - std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) - std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS multiplies : __binary_function<_Tp, _Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x * __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(multiplies);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS multiplies<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) * std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) * std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) * std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS divides : __binary_function<_Tp, _Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x / __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(divides);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS divides<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) / std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) / std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) / std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS modulus : __binary_function<_Tp, _Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x % __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(modulus);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS modulus<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) % std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) % std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) % std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS negate : __unary_function<_Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return -__x; }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(negate);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS negate<void> {
+ template <class _Tp>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_Tp&& __x) const
+ noexcept(noexcept(-std::forward<_Tp>(__x))) //
+ -> decltype(-std::forward<_Tp>(__x)) {
+ return -std::forward<_Tp>(__x);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+// Bitwise operations
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS bit_and : __binary_function<_Tp, _Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x & __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(bit_and);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS bit_and<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) &
+ std::forward<_T2>(__u))) -> decltype(std::forward<_T1>(__t) & std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) & std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+struct _LIBCPP_TEMPLATE_VIS bit_not : __unary_function<_Tp, _Tp> {
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return ~__x; }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(bit_not);
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS bit_not<void> {
+ template <class _Tp>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_Tp&& __x) const
+ noexcept(noexcept(~std::forward<_Tp>(__x))) //
+ -> decltype(~std::forward<_Tp>(__x)) {
+ return ~std::forward<_Tp>(__x);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS bit_or : __binary_function<_Tp, _Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x | __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(bit_or);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS bit_or<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) | std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) | std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) | std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS bit_xor : __binary_function<_Tp, _Tp, _Tp> {
+ typedef _Tp __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x ^ __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(bit_xor);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS bit_xor<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) ^ std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) ^ std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) ^ std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+// Comparison operations
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS equal_to : __binary_function<_Tp, _Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x == __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(equal_to);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS equal_to<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) == std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) == std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) == std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+// The non-transparent std::equal_to specialization is only equivalent to a raw equality
+// comparison when we don't perform an implicit conversion when calling it.
+template <class _Tp>
+inline const bool __desugars_to_v<__equal_tag, equal_to<_Tp>, _Tp, _Tp> = true;
+
+// In the transparent case, we do not enforce that
+template <class _Tp, class _Up>
+inline const bool __desugars_to_v<__equal_tag, equal_to<void>, _Tp, _Up> = true;
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS not_equal_to : __binary_function<_Tp, _Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x != __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(not_equal_to);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS not_equal_to<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) != std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) != std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) != std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS less : __binary_function<_Tp, _Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x < __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(less);
+
+template <class _Tp>
+inline const bool __desugars_to_v<__less_tag, less<_Tp>, _Tp, _Tp> = true;
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS less<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) < std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) < std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) < std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+
+template <class _Tp>
+inline const bool __desugars_to_v<__less_tag, less<>, _Tp, _Tp> = true;
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS less_equal : __binary_function<_Tp, _Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x <= __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(less_equal);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS less_equal<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) <= std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) <= std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) <= std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS greater_equal : __binary_function<_Tp, _Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x >= __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(greater_equal);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS greater_equal<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) >=
+ std::forward<_T2>(__u))) -> decltype(std::forward<_T1>(__t) >= std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) >= std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS greater : __binary_function<_Tp, _Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x > __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(greater);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS greater<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) > std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) > std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) > std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+// Logical operations
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS logical_and : __binary_function<_Tp, _Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x && __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(logical_and);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS logical_and<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) && std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) && std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) && std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS logical_not : __unary_function<_Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x) const { return !__x; }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(logical_not);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS logical_not<void> {
+ template <class _Tp>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_Tp&& __x) const
+ noexcept(noexcept(!std::forward<_Tp>(__x))) //
+ -> decltype(!std::forward<_Tp>(__x)) {
+ return !std::forward<_Tp>(__x);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp = void>
+#else
+template <class _Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS logical_or : __binary_function<_Tp, _Tp, bool> {
+ typedef bool __result_type; // used by valarray
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return __x || __y;
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(logical_or);
+
+#if _LIBCPP_STD_VER >= 14
+template <>
+struct _LIBCPP_TEMPLATE_VIS logical_or<void> {
+ template <class _T1, class _T2>
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI auto operator()(_T1&& __t, _T2&& __u) const
+ noexcept(noexcept(std::forward<_T1>(__t) || std::forward<_T2>(__u))) //
+ -> decltype(std::forward<_T1>(__t) || std::forward<_T2>(__u)) {
+ return std::forward<_T1>(__t) || std::forward<_T2>(__u);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_OPERATIONS_H
diff --git a/libcxx/include/__cxx03/__functional/perfect_forward.h b/libcxx/include/__cxx03/__functional/perfect_forward.h
new file mode 100644
index 00000000000000..74177c789b4ad0
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/perfect_forward.h
@@ -0,0 +1,104 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_PERFECT_FORWARD_H
+#define _LIBCPP___FUNCTIONAL_PERFECT_FORWARD_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/is_constructible.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/integer_sequence.h>
+#include <__utility/move.h>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Op, class _Indices, class... _BoundArgs>
+struct __perfect_forward_impl;
+
+template <class _Op, size_t... _Idx, class... _BoundArgs>
+struct __perfect_forward_impl<_Op, index_sequence<_Idx...>, _BoundArgs...> {
+private:
+ tuple<_BoundArgs...> __bound_args_;
+
+public:
+ template <class... _Args, class = enable_if_t< is_constructible_v<tuple<_BoundArgs...>, _Args&&...> >>
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr __perfect_forward_impl(_Args&&... __bound_args)
+ : __bound_args_(std::forward<_Args>(__bound_args)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI __perfect_forward_impl(__perfect_forward_impl const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __perfect_forward_impl(__perfect_forward_impl&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI __perfect_forward_impl& operator=(__perfect_forward_impl const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __perfect_forward_impl& operator=(__perfect_forward_impl&&) = default;
+
+ template <class... _Args, class = enable_if_t<is_invocable_v<_Op, _BoundArgs&..., _Args...>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Args&&... __args) & noexcept(
+ noexcept(_Op()(std::get<_Idx>(__bound_args_)..., std::forward<_Args>(__args)...)))
+ -> decltype(_Op()(std::get<_Idx>(__bound_args_)..., std::forward<_Args>(__args)...)) {
+ return _Op()(std::get<_Idx>(__bound_args_)..., std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args, class = enable_if_t<!is_invocable_v<_Op, _BoundArgs&..., _Args...>>>
+ auto operator()(_Args&&...) & = delete;
+
+ template <class... _Args, class = enable_if_t<is_invocable_v<_Op, _BoundArgs const&..., _Args...>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Args&&... __args) const& noexcept(
+ noexcept(_Op()(std::get<_Idx>(__bound_args_)..., std::forward<_Args>(__args)...)))
+ -> decltype(_Op()(std::get<_Idx>(__bound_args_)..., std::forward<_Args>(__args)...)) {
+ return _Op()(std::get<_Idx>(__bound_args_)..., std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args, class = enable_if_t<!is_invocable_v<_Op, _BoundArgs const&..., _Args...>>>
+ auto operator()(_Args&&...) const& = delete;
+
+ template <class... _Args, class = enable_if_t<is_invocable_v<_Op, _BoundArgs..., _Args...>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Args&&... __args) && noexcept(
+ noexcept(_Op()(std::get<_Idx>(std::move(__bound_args_))..., std::forward<_Args>(__args)...)))
+ -> decltype(_Op()(std::get<_Idx>(std::move(__bound_args_))..., std::forward<_Args>(__args)...)) {
+ return _Op()(std::get<_Idx>(std::move(__bound_args_))..., std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args, class = enable_if_t<!is_invocable_v<_Op, _BoundArgs..., _Args...>>>
+ auto operator()(_Args&&...) && = delete;
+
+ template <class... _Args, class = enable_if_t<is_invocable_v<_Op, _BoundArgs const..., _Args...>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Args&&... __args) const&& noexcept(
+ noexcept(_Op()(std::get<_Idx>(std::move(__bound_args_))..., std::forward<_Args>(__args)...)))
+ -> decltype(_Op()(std::get<_Idx>(std::move(__bound_args_))..., std::forward<_Args>(__args)...)) {
+ return _Op()(std::get<_Idx>(std::move(__bound_args_))..., std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args, class = enable_if_t<!is_invocable_v<_Op, _BoundArgs const..., _Args...>>>
+ auto operator()(_Args&&...) const&& = delete;
+};
+
+// __perfect_forward implements a perfect-forwarding call wrapper as explained in [func.require].
+template <class _Op, class... _Args>
+using __perfect_forward = __perfect_forward_impl<_Op, index_sequence_for<_Args...>, _Args...>;
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FUNCTIONAL_PERFECT_FORWARD_H
diff --git a/libcxx/include/__cxx03/__functional/pointer_to_binary_function.h b/libcxx/include/__cxx03/__functional/pointer_to_binary_function.h
new file mode 100644
index 00000000000000..e345250dcdd872
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/pointer_to_binary_function.h
@@ -0,0 +1,44 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_POINTER_TO_BINARY_FUNCTION_H
+#define _LIBCPP___FUNCTIONAL_POINTER_TO_BINARY_FUNCTION_H
+
+#include <__config>
+#include <__functional/binary_function.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+template <class _Arg1, class _Arg2, class _Result>
+class _LIBCPP_TEMPLATE_VIS
+_LIBCPP_DEPRECATED_IN_CXX11 pointer_to_binary_function : public __binary_function<_Arg1, _Arg2, _Result> {
+ _Result (*__f_)(_Arg1, _Arg2);
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit pointer_to_binary_function(_Result (*__f)(_Arg1, _Arg2)) : __f_(__f) {}
+ _LIBCPP_HIDE_FROM_ABI _Result operator()(_Arg1 __x, _Arg2 __y) const { return __f_(__x, __y); }
+};
+
+template <class _Arg1, class _Arg2, class _Result>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI pointer_to_binary_function<_Arg1, _Arg2, _Result>
+ptr_fun(_Result (*__f)(_Arg1, _Arg2)) {
+ return pointer_to_binary_function<_Arg1, _Arg2, _Result>(__f);
+}
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_POINTER_TO_BINARY_FUNCTION_H
diff --git a/libcxx/include/__cxx03/__functional/pointer_to_unary_function.h b/libcxx/include/__cxx03/__functional/pointer_to_unary_function.h
new file mode 100644
index 00000000000000..3a5d153d36178c
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/pointer_to_unary_function.h
@@ -0,0 +1,44 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_POINTER_TO_UNARY_FUNCTION_H
+#define _LIBCPP___FUNCTIONAL_POINTER_TO_UNARY_FUNCTION_H
+
+#include <__config>
+#include <__functional/unary_function.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+template <class _Arg, class _Result>
+class _LIBCPP_TEMPLATE_VIS
+_LIBCPP_DEPRECATED_IN_CXX11 pointer_to_unary_function : public __unary_function<_Arg, _Result> {
+ _Result (*__f_)(_Arg);
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit pointer_to_unary_function(_Result (*__f)(_Arg)) : __f_(__f) {}
+ _LIBCPP_HIDE_FROM_ABI _Result operator()(_Arg __x) const { return __f_(__x); }
+};
+
+template <class _Arg, class _Result>
+_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_HIDE_FROM_ABI pointer_to_unary_function<_Arg, _Result>
+ptr_fun(_Result (*__f)(_Arg)) {
+ return pointer_to_unary_function<_Arg, _Result>(__f);
+}
+
+#endif // _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_POINTER_TO_UNARY_FUNCTION_H
diff --git a/libcxx/include/__cxx03/__functional/ranges_operations.h b/libcxx/include/__cxx03/__functional/ranges_operations.h
new file mode 100644
index 00000000000000..27f06eadd0eb11
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/ranges_operations.h
@@ -0,0 +1,109 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_RANGES_OPERATIONS_H
+#define _LIBCPP___FUNCTIONAL_RANGES_OPERATIONS_H
+
+#include <__concepts/equality_comparable.h>
+#include <__concepts/totally_ordered.h>
+#include <__config>
+#include <__type_traits/desugars_to.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+struct equal_to {
+ template <class _Tp, class _Up>
+ requires equality_comparable_with<_Tp, _Up>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(bool(std::forward<_Tp>(__t) == std::forward<_Up>(__u)))) {
+ return std::forward<_Tp>(__t) == std::forward<_Up>(__u);
+ }
+
+ using is_transparent = void;
+};
+
+struct not_equal_to {
+ template <class _Tp, class _Up>
+ requires equality_comparable_with<_Tp, _Up>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(bool(!(std::forward<_Tp>(__t) == std::forward<_Up>(__u))))) {
+ return !(std::forward<_Tp>(__t) == std::forward<_Up>(__u));
+ }
+
+ using is_transparent = void;
+};
+
+struct less {
+ template <class _Tp, class _Up>
+ requires totally_ordered_with<_Tp, _Up>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(bool(std::forward<_Tp>(__t) < std::forward<_Up>(__u)))) {
+ return std::forward<_Tp>(__t) < std::forward<_Up>(__u);
+ }
+
+ using is_transparent = void;
+};
+
+struct less_equal {
+ template <class _Tp, class _Up>
+ requires totally_ordered_with<_Tp, _Up>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(bool(!(std::forward<_Up>(__u) < std::forward<_Tp>(__t))))) {
+ return !(std::forward<_Up>(__u) < std::forward<_Tp>(__t));
+ }
+
+ using is_transparent = void;
+};
+
+struct greater {
+ template <class _Tp, class _Up>
+ requires totally_ordered_with<_Tp, _Up>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(bool(std::forward<_Up>(__u) < std::forward<_Tp>(__t)))) {
+ return std::forward<_Up>(__u) < std::forward<_Tp>(__t);
+ }
+
+ using is_transparent = void;
+};
+
+struct greater_equal {
+ template <class _Tp, class _Up>
+ requires totally_ordered_with<_Tp, _Up>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
+ noexcept(noexcept(bool(!(std::forward<_Tp>(__t) < std::forward<_Up>(__u))))) {
+ return !(std::forward<_Tp>(__t) < std::forward<_Up>(__u));
+ }
+
+ using is_transparent = void;
+};
+
+} // namespace ranges
+
+// For ranges we do not require that the types on each side of the equality
+// operator are of the same type
+template <class _Tp, class _Up>
+inline const bool __desugars_to_v<__equal_tag, ranges::equal_to, _Tp, _Up> = true;
+
+template <class _Tp, class _Up>
+inline const bool __desugars_to_v<__less_tag, ranges::less, _Tp, _Up> = true;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_RANGES_OPERATIONS_H
diff --git a/libcxx/include/__cxx03/__functional/reference_wrapper.h b/libcxx/include/__cxx03/__functional/reference_wrapper.h
new file mode 100644
index 00000000000000..3570e2673c8005
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/reference_wrapper.h
@@ -0,0 +1,154 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_REFERENCE_WRAPPER_H
+#define _LIBCPP___FUNCTIONAL_REFERENCE_WRAPPER_H
+
+#include <__compare/synth_three_way.h>
+#include <__concepts/boolean_testable.h>
+#include <__config>
+#include <__functional/invoke.h>
+#include <__functional/weak_result_type.h>
+#include <__memory/addressof.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS reference_wrapper : public __weak_result_type<_Tp> {
+public:
+ // types
+ typedef _Tp type;
+
+private:
+ type* __f_;
+
+ static void __fun(_Tp&) _NOEXCEPT;
+ static void __fun(_Tp&&) = delete; // NOLINT(modernize-use-equals-delete) ; This is llvm.org/PR54276
+
+public:
+ template <class _Up,
+ class = __void_t<decltype(__fun(std::declval<_Up>()))>,
+ __enable_if_t<!__is_same_uncvref<_Up, reference_wrapper>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference_wrapper(_Up&& __u)
+ _NOEXCEPT_(noexcept(__fun(std::declval<_Up>()))) {
+ type& __f = static_cast<_Up&&>(__u);
+ __f_ = std::addressof(__f);
+ }
+
+ // access
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 operator type&() const _NOEXCEPT { return *__f_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 type& get() const _NOEXCEPT { return *__f_; }
+
+ // invoke
+ template <class... _ArgTypes>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename __invoke_of<type&, _ArgTypes...>::type
+ operator()(_ArgTypes&&... __args) const
+#if _LIBCPP_STD_VER >= 17
+ // Since is_nothrow_invocable requires C++17 LWG3764 is not backported
+ // to earlier versions.
+ noexcept(is_nothrow_invocable_v<_Tp&, _ArgTypes...>)
+#endif
+ {
+ return std::__invoke(get(), std::forward<_ArgTypes>(__args)...);
+ }
+
+#if _LIBCPP_STD_VER >= 26
+
+ // [refwrap.comparisons], comparisons
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(reference_wrapper __x, reference_wrapper __y)
+ requires requires {
+ { __x.get() == __y.get() } -> __boolean_testable;
+ }
+ {
+ return __x.get() == __y.get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(reference_wrapper __x, const _Tp& __y)
+ requires requires {
+ { __x.get() == __y } -> __boolean_testable;
+ }
+ {
+ return __x.get() == __y;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(reference_wrapper __x, reference_wrapper<const _Tp> __y)
+ requires(!is_const_v<_Tp>) && requires {
+ { __x.get() == __y.get() } -> __boolean_testable;
+ }
+ {
+ return __x.get() == __y.get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(reference_wrapper __x, reference_wrapper __y)
+ requires requires { std::__synth_three_way(__x.get(), __y.get()); }
+ {
+ return std::__synth_three_way(__x.get(), __y.get());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(reference_wrapper __x, const _Tp& __y)
+ requires requires { std::__synth_three_way(__x.get(), __y); }
+ {
+ return std::__synth_three_way(__x.get(), __y);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(reference_wrapper __x, reference_wrapper<const _Tp> __y)
+ requires(!is_const_v<_Tp>) && requires { std::__synth_three_way(__x.get(), __y.get()); }
+ {
+ return std::__synth_three_way(__x.get(), __y.get());
+ }
+
+#endif // _LIBCPP_STD_VER >= 26
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+reference_wrapper(_Tp&) -> reference_wrapper<_Tp>;
+#endif
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference_wrapper<_Tp> ref(_Tp& __t) _NOEXCEPT {
+ return reference_wrapper<_Tp>(__t);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference_wrapper<_Tp>
+ref(reference_wrapper<_Tp> __t) _NOEXCEPT {
+ return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference_wrapper<const _Tp> cref(const _Tp& __t) _NOEXCEPT {
+ return reference_wrapper<const _Tp>(__t);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference_wrapper<const _Tp>
+cref(reference_wrapper<_Tp> __t) _NOEXCEPT {
+ return __t;
+}
+
+template <class _Tp>
+void ref(const _Tp&&) = delete;
+template <class _Tp>
+void cref(const _Tp&&) = delete;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_REFERENCE_WRAPPER_H
diff --git a/libcxx/include/__cxx03/__functional/unary_function.h b/libcxx/include/__cxx03/__functional/unary_function.h
new file mode 100644
index 00000000000000..69b1bc94220ae6
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/unary_function.h
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_UNARY_FUNCTION_H
+#define _LIBCPP___FUNCTIONAL_UNARY_FUNCTION_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNARY_BINARY_FUNCTION)
+
+template <class _Arg, class _Result>
+struct _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 unary_function {
+ typedef _Arg argument_type;
+ typedef _Result result_type;
+};
+
+#endif // _LIBCPP_STD_VER <= 14
+
+template <class _Arg, class _Result>
+struct __unary_function_keep_layout_base {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using argument_type _LIBCPP_DEPRECATED_IN_CXX17 = _Arg;
+ using result_type _LIBCPP_DEPRECATED_IN_CXX17 = _Result;
+#endif
+};
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNARY_BINARY_FUNCTION)
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wdeprecated-declarations")
+template <class _Arg, class _Result>
+using __unary_function = unary_function<_Arg, _Result>;
+_LIBCPP_DIAGNOSTIC_POP
+#else
+template <class _Arg, class _Result>
+using __unary_function = __unary_function_keep_layout_base<_Arg, _Result>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_UNARY_FUNCTION_H
diff --git a/libcxx/include/__cxx03/__functional/unary_negate.h b/libcxx/include/__cxx03/__functional/unary_negate.h
new file mode 100644
index 00000000000000..5bd487a97bcb33
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/unary_negate.h
@@ -0,0 +1,48 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_UNARY_NEGATE_H
+#define _LIBCPP___FUNCTIONAL_UNARY_NEGATE_H
+
+#include <__config>
+#include <__functional/unary_function.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_NEGATORS)
+
+template <class _Predicate>
+class _LIBCPP_TEMPLATE_VIS
+_LIBCPP_DEPRECATED_IN_CXX17 unary_negate : public __unary_function<typename _Predicate::argument_type, bool> {
+ _Predicate __pred_;
+
+public:
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI explicit unary_negate(const _Predicate& __pred)
+ : __pred_(__pred) {}
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const typename _Predicate::argument_type& __x) const {
+ return !__pred_(__x);
+ }
+};
+
+template <class _Predicate>
+_LIBCPP_DEPRECATED_IN_CXX17 inline _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI unary_negate<_Predicate>
+not1(const _Predicate& __pred) {
+ return unary_negate<_Predicate>(__pred);
+}
+
+#endif // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_NEGATORS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_UNARY_NEGATE_H
diff --git a/libcxx/include/__cxx03/__functional/weak_result_type.h b/libcxx/include/__cxx03/__functional/weak_result_type.h
new file mode 100644
index 00000000000000..ad7a8395186cd5
--- /dev/null
+++ b/libcxx/include/__cxx03/__functional/weak_result_type.h
@@ -0,0 +1,231 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_WEAK_RESULT_TYPE_H
+#define _LIBCPP___FUNCTIONAL_WEAK_RESULT_TYPE_H
+
+#include <__config>
+#include <__functional/binary_function.h>
+#include <__functional/invoke.h>
+#include <__functional/unary_function.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __has_result_type {
+private:
+ template <class _Up>
+ static false_type __test(...);
+ template <class _Up>
+ static true_type __test(typename _Up::result_type* = 0);
+
+public:
+ static const bool value = decltype(__test<_Tp>(0))::value;
+};
+
+// __weak_result_type
+
+template <class _Tp>
+struct __derives_from_unary_function {
+private:
+ struct __two {
+ char __lx;
+ char __lxx;
+ };
+ static __two __test(...);
+ template <class _Ap, class _Rp>
+ static __unary_function<_Ap, _Rp> __test(const volatile __unary_function<_Ap, _Rp>*);
+
+public:
+ static const bool value = !is_same<decltype(__test((_Tp*)0)), __two>::value;
+ typedef decltype(__test((_Tp*)0)) type;
+};
+
+template <class _Tp>
+struct __derives_from_binary_function {
+private:
+ struct __two {
+ char __lx;
+ char __lxx;
+ };
+ static __two __test(...);
+ template <class _A1, class _A2, class _Rp>
+ static __binary_function<_A1, _A2, _Rp> __test(const volatile __binary_function<_A1, _A2, _Rp>*);
+
+public:
+ static const bool value = !is_same<decltype(__test((_Tp*)0)), __two>::value;
+ typedef decltype(__test((_Tp*)0)) type;
+};
+
+template <class _Tp, bool = __derives_from_unary_function<_Tp>::value>
+struct __maybe_derive_from_unary_function // bool is true
+ : public __derives_from_unary_function<_Tp>::type {};
+
+template <class _Tp>
+struct __maybe_derive_from_unary_function<_Tp, false> {};
+
+template <class _Tp, bool = __derives_from_binary_function<_Tp>::value>
+struct __maybe_derive_from_binary_function // bool is true
+ : public __derives_from_binary_function<_Tp>::type {};
+
+template <class _Tp>
+struct __maybe_derive_from_binary_function<_Tp, false> {};
+
+template <class _Tp, bool = __has_result_type<_Tp>::value>
+struct __weak_result_type_imp // bool is true
+ : public __maybe_derive_from_unary_function<_Tp>,
+ public __maybe_derive_from_binary_function<_Tp> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = typename _Tp::result_type;
+#endif
+};
+
+template <class _Tp>
+struct __weak_result_type_imp<_Tp, false>
+ : public __maybe_derive_from_unary_function<_Tp>, public __maybe_derive_from_binary_function<_Tp> {};
+
+template <class _Tp>
+struct __weak_result_type : public __weak_result_type_imp<_Tp> {};
+
+// 0 argument case
+
+template <class _Rp>
+struct __weak_result_type<_Rp()> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Rp>
+struct __weak_result_type<_Rp (&)()> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Rp>
+struct __weak_result_type<_Rp (*)()> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+// 1 argument case
+
+template <class _Rp, class _A1>
+struct __weak_result_type<_Rp(_A1)> : public __unary_function<_A1, _Rp> {};
+
+template <class _Rp, class _A1>
+struct __weak_result_type<_Rp (&)(_A1)> : public __unary_function<_A1, _Rp> {};
+
+template <class _Rp, class _A1>
+struct __weak_result_type<_Rp (*)(_A1)> : public __unary_function<_A1, _Rp> {};
+
+template <class _Rp, class _Cp>
+struct __weak_result_type<_Rp (_Cp::*)()> : public __unary_function<_Cp*, _Rp> {};
+
+template <class _Rp, class _Cp>
+struct __weak_result_type<_Rp (_Cp::*)() const> : public __unary_function<const _Cp*, _Rp> {};
+
+template <class _Rp, class _Cp>
+struct __weak_result_type<_Rp (_Cp::*)() volatile> : public __unary_function<volatile _Cp*, _Rp> {};
+
+template <class _Rp, class _Cp>
+struct __weak_result_type<_Rp (_Cp::*)() const volatile> : public __unary_function<const volatile _Cp*, _Rp> {};
+
+// 2 argument case
+
+template <class _Rp, class _A1, class _A2>
+struct __weak_result_type<_Rp(_A1, _A2)> : public __binary_function<_A1, _A2, _Rp> {};
+
+template <class _Rp, class _A1, class _A2>
+struct __weak_result_type<_Rp (*)(_A1, _A2)> : public __binary_function<_A1, _A2, _Rp> {};
+
+template <class _Rp, class _A1, class _A2>
+struct __weak_result_type<_Rp (&)(_A1, _A2)> : public __binary_function<_A1, _A2, _Rp> {};
+
+template <class _Rp, class _Cp, class _A1>
+struct __weak_result_type<_Rp (_Cp::*)(_A1)> : public __binary_function<_Cp*, _A1, _Rp> {};
+
+template <class _Rp, class _Cp, class _A1>
+struct __weak_result_type<_Rp (_Cp::*)(_A1) const> : public __binary_function<const _Cp*, _A1, _Rp> {};
+
+template <class _Rp, class _Cp, class _A1>
+struct __weak_result_type<_Rp (_Cp::*)(_A1) volatile> : public __binary_function<volatile _Cp*, _A1, _Rp> {};
+
+template <class _Rp, class _Cp, class _A1>
+struct __weak_result_type<_Rp (_Cp::*)(_A1) const volatile> : public __binary_function<const volatile _Cp*, _A1, _Rp> {
+};
+
+// 3 or more arguments
+
+template <class _Rp, class _A1, class _A2, class _A3, class... _A4>
+struct __weak_result_type<_Rp(_A1, _A2, _A3, _A4...)> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Rp, class _A1, class _A2, class _A3, class... _A4>
+struct __weak_result_type<_Rp (&)(_A1, _A2, _A3, _A4...)> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Rp, class _A1, class _A2, class _A3, class... _A4>
+struct __weak_result_type<_Rp (*)(_A1, _A2, _A3, _A4...)> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Rp, class _Cp, class _A1, class _A2, class... _A3>
+struct __weak_result_type<_Rp (_Cp::*)(_A1, _A2, _A3...)> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Rp, class _Cp, class _A1, class _A2, class... _A3>
+struct __weak_result_type<_Rp (_Cp::*)(_A1, _A2, _A3...) const> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Rp, class _Cp, class _A1, class _A2, class... _A3>
+struct __weak_result_type<_Rp (_Cp::*)(_A1, _A2, _A3...) volatile> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Rp, class _Cp, class _A1, class _A2, class... _A3>
+struct __weak_result_type<_Rp (_Cp::*)(_A1, _A2, _A3...) const volatile> {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ using result_type _LIBCPP_NODEBUG _LIBCPP_DEPRECATED_IN_CXX17 = _Rp;
+#endif
+};
+
+template <class _Tp, class... _Args>
+struct __invoke_return {
+ typedef decltype(std::__invoke(std::declval<_Tp>(), std::declval<_Args>()...)) type;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_WEAK_RESULT_TYPE_H
diff --git a/libcxx/include/__cxx03/__fwd/array.h b/libcxx/include/__cxx03/__fwd/array.h
new file mode 100644
index 00000000000000..b429d0c5a95427
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/array.h
@@ -0,0 +1,46 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_ARRAY_H
+#define _LIBCPP___FWD_ARRAY_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, size_t _Size>
+struct _LIBCPP_TEMPLATE_VIS array;
+
+template <size_t _Ip, class _Tp, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp& get(array<_Tp, _Size>&) _NOEXCEPT;
+
+template <size_t _Ip, class _Tp, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp& get(const array<_Tp, _Size>&) _NOEXCEPT;
+
+#ifndef _LIBCPP_CXX03_LANG
+template <size_t _Ip, class _Tp, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp&& get(array<_Tp, _Size>&&) _NOEXCEPT;
+
+template <size_t _Ip, class _Tp, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&& get(const array<_Tp, _Size>&&) _NOEXCEPT;
+#endif
+
+template <class>
+struct __is_std_array : false_type {};
+
+template <class _Tp, size_t _Size>
+struct __is_std_array<array<_Tp, _Size> > : true_type {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_ARRAY_H
diff --git a/libcxx/include/__cxx03/__fwd/bit_reference.h b/libcxx/include/__cxx03/__fwd/bit_reference.h
new file mode 100644
index 00000000000000..237efb6db66429
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/bit_reference.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_BIT_REFERENCE_H
+#define _LIBCPP___FWD_BIT_REFERENCE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Cp, bool _IsConst, typename _Cp::__storage_type = 0>
+class __bit_iterator;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_BIT_REFERENCE_H
diff --git a/libcxx/include/__cxx03/__fwd/complex.h b/libcxx/include/__cxx03/__fwd/complex.h
new file mode 100644
index 00000000000000..22c78c5cc3c77a
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/complex.h
@@ -0,0 +1,42 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_COMPLEX_H
+#define _LIBCPP___FWD_COMPLEX_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS complex;
+
+#if _LIBCPP_STD_VER >= 26
+
+template <size_t _Ip, class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp& get(complex<_Tp>&) noexcept;
+
+template <size_t _Ip, class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp&& get(complex<_Tp>&&) noexcept;
+
+template <size_t _Ip, class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr const _Tp& get(const complex<_Tp>&) noexcept;
+
+template <size_t _Ip, class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr const _Tp&& get(const complex<_Tp>&&) noexcept;
+
+#endif // _LIBCPP_STD_VER >= 26
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_COMPLEX_H
diff --git a/libcxx/include/__cxx03/__fwd/deque.h b/libcxx/include/__cxx03/__fwd/deque.h
new file mode 100644
index 00000000000000..fd2fb5bb4b8e92
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/deque.h
@@ -0,0 +1,26 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_DEQUE_H
+#define _LIBCPP___FWD_DEQUE_H
+
+#include <__config>
+#include <__fwd/memory.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Allocator = allocator<_Tp> >
+class _LIBCPP_TEMPLATE_VIS deque;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_DEQUE_H
diff --git a/libcxx/include/__cxx03/__fwd/format.h b/libcxx/include/__cxx03/__fwd/format.h
new file mode 100644
index 00000000000000..b30c220f8a0435
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/format.h
@@ -0,0 +1,38 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_FORMAT_H
+#define _LIBCPP___FWD_FORMAT_H
+
+#include <__config>
+#include <__iterator/concepts.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Context>
+class _LIBCPP_TEMPLATE_VIS basic_format_arg;
+
+template <class _OutIt, class _CharT>
+ requires output_iterator<_OutIt, const _CharT&>
+class _LIBCPP_TEMPLATE_VIS basic_format_context;
+
+template <class _Tp, class _CharT = char>
+struct _LIBCPP_TEMPLATE_VIS formatter;
+
+#endif //_LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_FORMAT_H
diff --git a/libcxx/include/__cxx03/__fwd/fstream.h b/libcxx/include/__cxx03/__fwd/fstream.h
new file mode 100644
index 00000000000000..b4a112bfd4de64
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/fstream.h
@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_FSTREAM_H
+#define _LIBCPP___FWD_FSTREAM_H
+
+#include <__config>
+#include <__fwd/string.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_filebuf;
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_ifstream;
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_ofstream;
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_fstream;
+
+using filebuf = basic_filebuf<char>;
+using ifstream = basic_ifstream<char>;
+using ofstream = basic_ofstream<char>;
+using fstream = basic_fstream<char>;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wfilebuf = basic_filebuf<wchar_t>;
+using wifstream = basic_ifstream<wchar_t>;
+using wofstream = basic_ofstream<wchar_t>;
+using wfstream = basic_fstream<wchar_t>;
+#endif
+
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(filebuf) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wfilebuf)) basic_filebuf;
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(ifstream) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wifstream)) basic_ifstream;
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(ofstream) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wofstream)) basic_ofstream;
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(fstream) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wfstream)) basic_fstream;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_FSTREAM_H
diff --git a/libcxx/include/__cxx03/__fwd/functional.h b/libcxx/include/__cxx03/__fwd/functional.h
new file mode 100644
index 00000000000000..32c9ef33e453b1
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/functional.h
@@ -0,0 +1,28 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_FUNCTIONAL_H
+#define _LIBCPP___FWD_FUNCTIONAL_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class>
+struct _LIBCPP_TEMPLATE_VIS hash;
+
+template <class>
+class _LIBCPP_TEMPLATE_VIS reference_wrapper;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_FUNCTIONAL_H
diff --git a/libcxx/include/__cxx03/__fwd/ios.h b/libcxx/include/__cxx03/__fwd/ios.h
new file mode 100644
index 00000000000000..48350709d4ce25
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/ios.h
@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_IOS_H
+#define _LIBCPP___FWD_IOS_H
+
+#include <__config>
+#include <__fwd/string.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_EXPORTED_FROM_ABI ios_base;
+
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_ios;
+
+using ios = basic_ios<char>;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wios = basic_ios<wchar_t>;
+#endif
+
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(ios) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wios)) basic_ios;
+
+#if defined(_NEWLIB_VERSION)
+// On newlib, off_t is 'long int'
+using streamoff = long int; // for char_traits in <string>
+#else
+using streamoff = long long; // for char_traits in <string>
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_IOS_H
diff --git a/libcxx/include/__cxx03/__fwd/istream.h b/libcxx/include/__cxx03/__fwd/istream.h
new file mode 100644
index 00000000000000..a06907a6c8ef91
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/istream.h
@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_ISTREAM_H
+#define _LIBCPP___FWD_ISTREAM_H
+
+#include <__config>
+#include <__fwd/string.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_istream;
+
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_iostream;
+
+using istream = basic_istream<char>;
+using iostream = basic_iostream<char>;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wistream = basic_istream<wchar_t>;
+using wiostream = basic_iostream<wchar_t>;
+#endif
+
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(istream) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wistream)) basic_istream;
+
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(iostream) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wiostream)) basic_iostream;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_ISTREAM_H
diff --git a/libcxx/include/__cxx03/__fwd/mdspan.h b/libcxx/include/__cxx03/__fwd/mdspan.h
new file mode 100644
index 00000000000000..8889567a047f6e
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/mdspan.h
@@ -0,0 +1,57 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MDSPAN_LAYOUTS_H
+#define _LIBCPP___MDSPAN_LAYOUTS_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+// Layout policy with a mapping which corresponds to FORTRAN-style array layouts
+struct layout_left {
+ template <class _Extents>
+ class mapping;
+};
+
+// Layout policy with a mapping which corresponds to C-style array layouts
+struct layout_right {
+ template <class _Extents>
+ class mapping;
+};
+
+// Layout policy with a unique mapping where strides are arbitrary
+struct layout_stride {
+ template <class _Extents>
+ class mapping;
+};
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MDSPAN_LAYOUTS_H
diff --git a/libcxx/include/__cxx03/__fwd/memory.h b/libcxx/include/__cxx03/__fwd/memory.h
new file mode 100644
index 00000000000000..b9e151855ad7d8
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/memory.h
@@ -0,0 +1,25 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_MEMORY_H
+#define _LIBCPP___FWD_MEMORY_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS allocator;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_MEMORY_H
diff --git a/libcxx/include/__cxx03/__fwd/memory_resource.h b/libcxx/include/__cxx03/__fwd/memory_resource.h
new file mode 100644
index 00000000000000..d68b2c2b631543
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/memory_resource.h
@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_MEMORY_RESOURCE_H
+#define _LIBCPP___FWD_MEMORY_RESOURCE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace pmr {
+template <class _ValueType>
+class _LIBCPP_AVAILABILITY_PMR _LIBCPP_TEMPLATE_VIS polymorphic_allocator;
+} // namespace pmr
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_MEMORY_RESOURCE_H
diff --git a/libcxx/include/__cxx03/__fwd/ostream.h b/libcxx/include/__cxx03/__fwd/ostream.h
new file mode 100644
index 00000000000000..3347e0f71d7a1c
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/ostream.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_OSTREAM_H
+#define _LIBCPP___FWD_OSTREAM_H
+
+#include <__config>
+#include <__fwd/string.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_ostream;
+
+using ostream = basic_ostream<char>;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wostream = basic_ostream<wchar_t>;
+#endif
+
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(ostream) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wostream)) basic_ostream;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_OSTREAM_H
diff --git a/libcxx/include/__cxx03/__fwd/pair.h b/libcxx/include/__cxx03/__fwd/pair.h
new file mode 100644
index 00000000000000..af32628fe1e0d0
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/pair.h
@@ -0,0 +1,45 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_PAIR_H
+#define _LIBCPP___FWD_PAIR_H
+
+#include <__config>
+#include <__fwd/tuple.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class, class>
+struct _LIBCPP_TEMPLATE_VIS pair;
+
+template <size_t _Ip, class _T1, class _T2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, pair<_T1, _T2> >::type&
+get(pair<_T1, _T2>&) _NOEXCEPT;
+
+template <size_t _Ip, class _T1, class _T2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, pair<_T1, _T2> >::type&
+get(const pair<_T1, _T2>&) _NOEXCEPT;
+
+#ifndef _LIBCPP_CXX03_LANG
+template <size_t _Ip, class _T1, class _T2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
+get(pair<_T1, _T2>&&) _NOEXCEPT;
+
+template <size_t _Ip, class _T1, class _T2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
+get(const pair<_T1, _T2>&&) _NOEXCEPT;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_PAIR_H
diff --git a/libcxx/include/__cxx03/__fwd/queue.h b/libcxx/include/__cxx03/__fwd/queue.h
new file mode 100644
index 00000000000000..50d99ad9c29f45
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/queue.h
@@ -0,0 +1,31 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_QUEUE_H
+#define _LIBCPP___FWD_QUEUE_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__fwd/deque.h>
+#include <__fwd/vector.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Container = deque<_Tp> >
+class _LIBCPP_TEMPLATE_VIS queue;
+
+template <class _Tp, class _Container = vector<_Tp>, class _Compare = less<typename _Container::value_type> >
+class _LIBCPP_TEMPLATE_VIS priority_queue;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_QUEUE_H
diff --git a/libcxx/include/__cxx03/__fwd/span.h b/libcxx/include/__cxx03/__fwd/span.h
new file mode 100644
index 00000000000000..8dafa742c19df5
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/span.h
@@ -0,0 +1,38 @@
+// -*- C++ -*-
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_SPAN_H
+#define _LIBCPP___FWD_SPAN_H
+
+#include <__config>
+#include <cstddef>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+inline constexpr size_t dynamic_extent = numeric_limits<size_t>::max();
+template <typename _Tp, size_t _Extent = dynamic_extent>
+class span;
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FWD_SPAN_H
diff --git a/libcxx/include/__cxx03/__fwd/sstream.h b/libcxx/include/__cxx03/__fwd/sstream.h
new file mode 100644
index 00000000000000..39a9c3faf1f800
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/sstream.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_SSTREAM_H
+#define _LIBCPP___FWD_SSTREAM_H
+
+#include <__config>
+#include <__fwd/memory.h>
+#include <__fwd/string.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits = char_traits<_CharT>, class _Allocator = allocator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_stringbuf;
+
+template <class _CharT, class _Traits = char_traits<_CharT>, class _Allocator = allocator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_istringstream;
+template <class _CharT, class _Traits = char_traits<_CharT>, class _Allocator = allocator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_ostringstream;
+template <class _CharT, class _Traits = char_traits<_CharT>, class _Allocator = allocator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_stringstream;
+
+using stringbuf = basic_stringbuf<char>;
+using istringstream = basic_istringstream<char>;
+using ostringstream = basic_ostringstream<char>;
+using stringstream = basic_stringstream<char>;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wstringbuf = basic_stringbuf<wchar_t>;
+using wistringstream = basic_istringstream<wchar_t>;
+using wostringstream = basic_ostringstream<wchar_t>;
+using wstringstream = basic_stringstream<wchar_t>;
+#endif
+
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_PREFERRED_NAME(stringbuf) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wstringbuf)) basic_stringbuf;
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_PREFERRED_NAME(istringstream)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wistringstream)) basic_istringstream;
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_PREFERRED_NAME(ostringstream)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wostringstream)) basic_ostringstream;
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_PREFERRED_NAME(stringstream)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wstringstream)) basic_stringstream;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_SSTREAM_H
diff --git a/libcxx/include/__cxx03/__fwd/stack.h b/libcxx/include/__cxx03/__fwd/stack.h
new file mode 100644
index 00000000000000..7dab6c1a4f4e2e
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/stack.h
@@ -0,0 +1,26 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_STACK_H
+#define _LIBCPP___FWD_STACK_H
+
+#include <__config>
+#include <__fwd/deque.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Container = deque<_Tp> >
+class _LIBCPP_TEMPLATE_VIS stack;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_STACK_H
diff --git a/libcxx/include/__cxx03/__fwd/streambuf.h b/libcxx/include/__cxx03/__fwd/streambuf.h
new file mode 100644
index 00000000000000..b35afa6afe3437
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/streambuf.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_STREAMBUF_H
+#define _LIBCPP___FWD_STREAMBUF_H
+
+#include <__config>
+#include <__fwd/string.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_streambuf;
+
+using streambuf = basic_streambuf<char>;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wstreambuf = basic_streambuf<wchar_t>;
+#endif
+
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(streambuf) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wstreambuf)) basic_streambuf;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_STREAMBUF_H
diff --git a/libcxx/include/__cxx03/__fwd/string.h b/libcxx/include/__cxx03/__fwd/string.h
new file mode 100644
index 00000000000000..2418e1f9b23d0d
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/string.h
@@ -0,0 +1,107 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_STRING_H
+#define _LIBCPP___FWD_STRING_H
+
+#include <__config>
+#include <__fwd/memory.h>
+#include <__fwd/memory_resource.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT>
+struct _LIBCPP_TEMPLATE_VIS char_traits;
+template <>
+struct char_traits<char>;
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <>
+struct char_traits<char8_t>;
+#endif
+
+template <>
+struct char_traits<char16_t>;
+template <>
+struct char_traits<char32_t>;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+struct char_traits<wchar_t>;
+#endif
+
+template <class _CharT, class _Traits = char_traits<_CharT>, class _Allocator = allocator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_string;
+
+using string = basic_string<char>;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wstring = basic_string<wchar_t>;
+#endif
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+using u8string = basic_string<char8_t>;
+#endif
+
+using u16string = basic_string<char16_t>;
+using u32string = basic_string<char32_t>;
+
+#if _LIBCPP_STD_VER >= 17
+
+namespace pmr {
+template <class _CharT, class _Traits = char_traits<_CharT>>
+using basic_string _LIBCPP_AVAILABILITY_PMR = std::basic_string<_CharT, _Traits, polymorphic_allocator<_CharT>>;
+
+using string _LIBCPP_AVAILABILITY_PMR = basic_string<char>;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wstring _LIBCPP_AVAILABILITY_PMR = basic_string<wchar_t>;
+# endif
+
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+using u8string _LIBCPP_AVAILABILITY_PMR = basic_string<char8_t>;
+# endif
+
+using u16string _LIBCPP_AVAILABILITY_PMR = basic_string<char16_t>;
+using u32string _LIBCPP_AVAILABILITY_PMR = basic_string<char32_t>;
+} // namespace pmr
+
+#endif // _LIBCPP_STD_VER >= 17
+
+// clang-format off
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_PREFERRED_NAME(string)
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ _LIBCPP_PREFERRED_NAME(wstring)
+#endif
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+ _LIBCPP_PREFERRED_NAME(u8string)
+#endif
+ _LIBCPP_PREFERRED_NAME(u16string)
+ _LIBCPP_PREFERRED_NAME(u32string)
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_PREFERRED_NAME(pmr::string)
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ _LIBCPP_PREFERRED_NAME(pmr::wstring)
+# endif
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+ _LIBCPP_PREFERRED_NAME(pmr::u8string)
+# endif
+ _LIBCPP_PREFERRED_NAME(pmr::u16string)
+ _LIBCPP_PREFERRED_NAME(pmr::u32string)
+#endif
+ basic_string;
+// clang-format on
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_STRING_H
diff --git a/libcxx/include/__cxx03/__fwd/string_view.h b/libcxx/include/__cxx03/__fwd/string_view.h
new file mode 100644
index 00000000000000..72a64be5b00b54
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/string_view.h
@@ -0,0 +1,50 @@
+// -*- C++ -*-
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_STRING_VIEW_H
+#define _LIBCPP___FWD_STRING_VIEW_H
+
+#include <__config>
+#include <__fwd/string.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_string_view;
+
+typedef basic_string_view<char> string_view;
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+typedef basic_string_view<char8_t> u8string_view;
+#endif
+typedef basic_string_view<char16_t> u16string_view;
+typedef basic_string_view<char32_t> u32string_view;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+typedef basic_string_view<wchar_t> wstring_view;
+#endif
+
+// clang-format off
+template <class _CharT, class _Traits>
+class _LIBCPP_PREFERRED_NAME(string_view)
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ _LIBCPP_PREFERRED_NAME(wstring_view)
+#endif
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+ _LIBCPP_PREFERRED_NAME(u8string_view)
+#endif
+ _LIBCPP_PREFERRED_NAME(u16string_view)
+ _LIBCPP_PREFERRED_NAME(u32string_view)
+ basic_string_view;
+// clang-format on
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_STRING_VIEW_H
diff --git a/libcxx/include/__cxx03/__fwd/subrange.h b/libcxx/include/__cxx03/__fwd/subrange.h
new file mode 100644
index 00000000000000..60a41da23dd44e
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/subrange.h
@@ -0,0 +1,49 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_SUBRANGE_H
+#define _LIBCPP___FWD_SUBRANGE_H
+
+#include <__concepts/copyable.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+enum class subrange_kind : bool { unsized, sized };
+
+template <input_or_output_iterator _Iter, sentinel_for<_Iter> _Sent, subrange_kind _Kind>
+ requires(_Kind == subrange_kind::sized || !sized_sentinel_for<_Sent, _Iter>)
+class _LIBCPP_TEMPLATE_VIS subrange;
+
+template <size_t _Index, class _Iter, class _Sent, subrange_kind _Kind>
+ requires((_Index == 0 && copyable<_Iter>) || _Index == 1)
+_LIBCPP_HIDE_FROM_ABI constexpr auto get(const subrange<_Iter, _Sent, _Kind>&);
+
+template <size_t _Index, class _Iter, class _Sent, subrange_kind _Kind>
+ requires(_Index < 2)
+_LIBCPP_HIDE_FROM_ABI constexpr auto get(subrange<_Iter, _Sent, _Kind>&&);
+
+} // namespace ranges
+
+using ranges::get;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___FWD_SUBRANGE_H
diff --git a/libcxx/include/__cxx03/__fwd/tuple.h b/libcxx/include/__cxx03/__fwd/tuple.h
new file mode 100644
index 00000000000000..902770c29555ed
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/tuple.h
@@ -0,0 +1,52 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_TUPLE_H
+#define _LIBCPP___FWD_TUPLE_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t, class>
+struct _LIBCPP_TEMPLATE_VIS tuple_element;
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class...>
+class _LIBCPP_TEMPLATE_VIS tuple;
+
+template <class>
+struct _LIBCPP_TEMPLATE_VIS tuple_size;
+
+template <size_t _Ip, class... _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, tuple<_Tp...> >::type&
+get(tuple<_Tp...>&) _NOEXCEPT;
+
+template <size_t _Ip, class... _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, tuple<_Tp...> >::type&
+get(const tuple<_Tp...>&) _NOEXCEPT;
+
+template <size_t _Ip, class... _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, tuple<_Tp...> >::type&&
+get(tuple<_Tp...>&&) _NOEXCEPT;
+
+template <size_t _Ip, class... _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, tuple<_Tp...> >::type&&
+get(const tuple<_Tp...>&&) _NOEXCEPT;
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_TUPLE_H
diff --git a/libcxx/include/__cxx03/__fwd/vector.h b/libcxx/include/__cxx03/__fwd/vector.h
new file mode 100644
index 00000000000000..c9cc96137449f8
--- /dev/null
+++ b/libcxx/include/__cxx03/__fwd/vector.h
@@ -0,0 +1,26 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FWD_VECTOR_H
+#define _LIBCPP___FWD_VECTOR_H
+
+#include <__config>
+#include <__fwd/memory.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Alloc = allocator<_Tp> >
+class _LIBCPP_TEMPLATE_VIS vector;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FWD_VECTOR_H
diff --git a/libcxx/include/__cxx03/__hash_table b/libcxx/include/__cxx03/__hash_table
new file mode 100644
index 00000000000000..025758528573f2
--- /dev/null
+++ b/libcxx/include/__cxx03/__hash_table
@@ -0,0 +1,2044 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___HASH_TABLE
+#define _LIBCPP___HASH_TABLE
+
+#include <__algorithm/max.h>
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__bit/countl.h>
+#include <__config>
+#include <__functional/hash.h>
+#include <__functional/invoke.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/compressed_pair.h>
+#include <__memory/construct_at.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/swap_allocator.h>
+#include <__memory/unique_ptr.h>
+#include <__type_traits/can_extract_key.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/swap.h>
+#include <cmath>
+#include <cstring>
+#include <initializer_list>
+#include <new> // __launder
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Key, class _Tp>
+struct __hash_value_type;
+
+template <class _Tp>
+struct __is_hash_value_type_imp : false_type {};
+
+template <class _Key, class _Value>
+struct __is_hash_value_type_imp<__hash_value_type<_Key, _Value> > : true_type {};
+
+template <class... _Args>
+struct __is_hash_value_type : false_type {};
+
+template <class _One>
+struct __is_hash_value_type<_One> : __is_hash_value_type_imp<__remove_cvref_t<_One> > {};
+
+_LIBCPP_EXPORTED_FROM_ABI size_t __next_prime(size_t __n);
+
+template <class _NodePtr>
+struct __hash_node_base {
+ typedef typename pointer_traits<_NodePtr>::element_type __node_type;
+ typedef __hash_node_base __first_node;
+ typedef __rebind_pointer_t<_NodePtr, __first_node> __node_base_pointer;
+ typedef _NodePtr __node_pointer;
+
+#if defined(_LIBCPP_ABI_FIX_UNORDERED_NODE_POINTER_UB)
+ typedef __node_base_pointer __next_pointer;
+#else
+ typedef __conditional_t<is_pointer<__node_pointer>::value, __node_base_pointer, __node_pointer> __next_pointer;
+#endif
+
+ __next_pointer __next_;
+
+ _LIBCPP_HIDE_FROM_ABI __next_pointer __ptr() _NOEXCEPT {
+ return static_cast<__next_pointer>(pointer_traits<__node_base_pointer>::pointer_to(*this));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __upcast() _NOEXCEPT {
+ return static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(*this));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_t __hash() const _NOEXCEPT { return static_cast<__node_type const&>(*this).__hash_; }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_node_base() _NOEXCEPT : __next_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_node_base(__next_pointer __next) _NOEXCEPT : __next_(__next) {}
+};
+
+template <class _Tp, class _VoidPtr>
+struct __hash_node : public __hash_node_base< __rebind_pointer_t<_VoidPtr, __hash_node<_Tp, _VoidPtr> > > {
+ typedef _Tp __node_value_type;
+ using _Base = __hash_node_base<__rebind_pointer_t<_VoidPtr, __hash_node<_Tp, _VoidPtr> > >;
+ using __next_pointer = typename _Base::__next_pointer;
+
+ size_t __hash_;
+
+ // We allow starting the lifetime of nodes without initializing the value held by the node,
+ // since that is handled by the hash table itself in order to be allocator-aware.
+#ifndef _LIBCPP_CXX03_LANG
+
+private:
+ union {
+ _Tp __value_;
+ };
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _Tp& __get_value() { return __value_; }
+#else
+
+private:
+ _ALIGNAS_TYPE(_Tp) char __buffer_[sizeof(_Tp)];
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _Tp& __get_value() { return *std::__launder(reinterpret_cast<_Tp*>(&__buffer_)); }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_node(__next_pointer __next, size_t __hash) : _Base(__next), __hash_(__hash) {}
+ _LIBCPP_HIDE_FROM_ABI ~__hash_node() {}
+};
+
+inline _LIBCPP_HIDE_FROM_ABI bool __is_hash_power2(size_t __bc) { return __bc > 2 && !(__bc & (__bc - 1)); }
+
+inline _LIBCPP_HIDE_FROM_ABI size_t __constrain_hash(size_t __h, size_t __bc) {
+ return !(__bc & (__bc - 1)) ? __h & (__bc - 1) : (__h < __bc ? __h : __h % __bc);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t __next_hash_pow2(size_t __n) {
+ return __n < 2 ? __n : (size_t(1) << (numeric_limits<size_t>::digits - __libcpp_clz(__n - 1)));
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+class __hash_table;
+
+template <class _NodePtr>
+class _LIBCPP_TEMPLATE_VIS __hash_iterator;
+template <class _ConstNodePtr>
+class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
+template <class _NodePtr>
+class _LIBCPP_TEMPLATE_VIS __hash_local_iterator;
+template <class _ConstNodePtr>
+class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
+template <class _HashIterator>
+class _LIBCPP_TEMPLATE_VIS __hash_map_iterator;
+template <class _HashIterator>
+class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
+
+template <class _Tp>
+struct __hash_key_value_types {
+ static_assert(!is_reference<_Tp>::value && !is_const<_Tp>::value, "");
+ typedef _Tp key_type;
+ typedef _Tp __node_value_type;
+ typedef _Tp __container_value_type;
+ static const bool __is_map = false;
+
+ _LIBCPP_HIDE_FROM_ABI static key_type const& __get_key(_Tp const& __v) { return __v; }
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type const& __get_value(__node_value_type const& __v) { return __v; }
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type* __get_ptr(__node_value_type& __n) { return std::addressof(__n); }
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type&& __move(__node_value_type& __v) { return std::move(__v); }
+};
+
+template <class _Key, class _Tp>
+struct __hash_key_value_types<__hash_value_type<_Key, _Tp> > {
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef __hash_value_type<_Key, _Tp> __node_value_type;
+ typedef pair<const _Key, _Tp> __container_value_type;
+ typedef __container_value_type __map_value_type;
+ static const bool __is_map = true;
+
+ _LIBCPP_HIDE_FROM_ABI static key_type const& __get_key(__container_value_type const& __v) { return __v.first; }
+
+ template <class _Up, __enable_if_t<__is_same_uncvref<_Up, __node_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type const& __get_value(_Up& __t) {
+ return __t.__get_value();
+ }
+
+ template <class _Up, __enable_if_t<__is_same_uncvref<_Up, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type const& __get_value(_Up& __t) {
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type* __get_ptr(__node_value_type& __n) {
+ return std::addressof(__n.__get_value());
+ }
+ _LIBCPP_HIDE_FROM_ABI static pair<key_type&&, mapped_type&&> __move(__node_value_type& __v) { return __v.__move(); }
+};
+
+template <class _Tp, class _AllocPtr, class _KVTypes = __hash_key_value_types<_Tp>, bool = _KVTypes::__is_map>
+struct __hash_map_pointer_types {};
+
+template <class _Tp, class _AllocPtr, class _KVTypes>
+struct __hash_map_pointer_types<_Tp, _AllocPtr, _KVTypes, true> {
+ typedef typename _KVTypes::__map_value_type _Mv;
+ typedef __rebind_pointer_t<_AllocPtr, _Mv> __map_value_type_pointer;
+ typedef __rebind_pointer_t<_AllocPtr, const _Mv> __const_map_value_type_pointer;
+};
+
+template <class _NodePtr, class _NodeT = typename pointer_traits<_NodePtr>::element_type>
+struct __hash_node_types;
+
+template <class _NodePtr, class _Tp, class _VoidPtr>
+struct __hash_node_types<_NodePtr, __hash_node<_Tp, _VoidPtr> >
+ : public __hash_key_value_types<_Tp>,
+ __hash_map_pointer_types<_Tp, _VoidPtr>
+
+{
+ typedef __hash_key_value_types<_Tp> __base;
+
+public:
+ typedef ptrdiff_t difference_type;
+ typedef size_t size_type;
+
+ typedef __rebind_pointer_t<_NodePtr, void> __void_pointer;
+
+ typedef typename pointer_traits<_NodePtr>::element_type __node_type;
+ typedef _NodePtr __node_pointer;
+
+ typedef __hash_node_base<__node_pointer> __node_base_type;
+ typedef __rebind_pointer_t<_NodePtr, __node_base_type> __node_base_pointer;
+
+ typedef typename __node_base_type::__next_pointer __next_pointer;
+
+ typedef _Tp __node_value_type;
+ typedef __rebind_pointer_t<_VoidPtr, __node_value_type> __node_value_type_pointer;
+ typedef __rebind_pointer_t<_VoidPtr, const __node_value_type> __const_node_value_type_pointer;
+
+private:
+ static_assert(!is_const<__node_type>::value, "_NodePtr should never be a pointer to const");
+ static_assert(is_same<typename pointer_traits<_VoidPtr>::element_type, void>::value,
+ "_VoidPtr does not point to unqualified void type");
+ static_assert(is_same<__rebind_pointer_t<_VoidPtr, __node_type>, _NodePtr>::value,
+ "_VoidPtr does not rebind to _NodePtr.");
+};
+
+template <class _HashIterator>
+struct __hash_node_types_from_iterator;
+template <class _NodePtr>
+struct __hash_node_types_from_iterator<__hash_iterator<_NodePtr> > : __hash_node_types<_NodePtr> {};
+template <class _NodePtr>
+struct __hash_node_types_from_iterator<__hash_const_iterator<_NodePtr> > : __hash_node_types<_NodePtr> {};
+template <class _NodePtr>
+struct __hash_node_types_from_iterator<__hash_local_iterator<_NodePtr> > : __hash_node_types<_NodePtr> {};
+template <class _NodePtr>
+struct __hash_node_types_from_iterator<__hash_const_local_iterator<_NodePtr> > : __hash_node_types<_NodePtr> {};
+
+template <class _NodeValueTp, class _VoidPtr>
+struct __make_hash_node_types {
+ typedef __hash_node<_NodeValueTp, _VoidPtr> _NodeTp;
+ typedef __rebind_pointer_t<_VoidPtr, _NodeTp> _NodePtr;
+ typedef __hash_node_types<_NodePtr> type;
+};
+
+template <class _NodePtr>
+class _LIBCPP_TEMPLATE_VIS __hash_iterator {
+ typedef __hash_node_types<_NodePtr> _NodeTypes;
+ typedef _NodePtr __node_pointer;
+ typedef typename _NodeTypes::__next_pointer __next_pointer;
+
+ __next_pointer __node_;
+
+public:
+ typedef forward_iterator_tag iterator_category;
+ typedef typename _NodeTypes::__node_value_type value_type;
+ typedef typename _NodeTypes::difference_type difference_type;
+ typedef value_type& reference;
+ typedef typename _NodeTypes::__node_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_iterator() _NOEXCEPT : __node_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to dereference a non-dereferenceable unordered container iterator");
+ return __node_->__upcast()->__get_value();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to dereference a non-dereferenceable unordered container iterator");
+ return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_iterator& operator++() {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to increment a non-incrementable unordered container iterator");
+ __node_ = __node_->__next_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_iterator operator++(int) {
+ __hash_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __hash_iterator& __x, const __hash_iterator& __y) {
+ return __x.__node_ == __y.__node_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __hash_iterator& __x, const __hash_iterator& __y) {
+ return !(__x == __y);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_iterator(__next_pointer __node) _NOEXCEPT : __node_(__node) {}
+
+ template <class, class, class, class>
+ friend class __hash_table;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_map_iterator;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
+};
+
+template <class _NodePtr>
+class _LIBCPP_TEMPLATE_VIS __hash_const_iterator {
+ static_assert(!is_const<typename pointer_traits<_NodePtr>::element_type>::value, "");
+ typedef __hash_node_types<_NodePtr> _NodeTypes;
+ typedef _NodePtr __node_pointer;
+ typedef typename _NodeTypes::__next_pointer __next_pointer;
+
+ __next_pointer __node_;
+
+public:
+ typedef __hash_iterator<_NodePtr> __non_const_iterator;
+
+ typedef forward_iterator_tag iterator_category;
+ typedef typename _NodeTypes::__node_value_type value_type;
+ typedef typename _NodeTypes::difference_type difference_type;
+ typedef const value_type& reference;
+ typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_const_iterator() _NOEXCEPT : __node_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI __hash_const_iterator(const __non_const_iterator& __x) _NOEXCEPT : __node_(__x.__node_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to dereference a non-dereferenceable unordered container const_iterator");
+ return __node_->__upcast()->__get_value();
+ }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to dereference a non-dereferenceable unordered container const_iterator");
+ return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_const_iterator& operator++() {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to increment a non-incrementable unordered container const_iterator");
+ __node_ = __node_->__next_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_const_iterator operator++(int) {
+ __hash_const_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __hash_const_iterator& __x, const __hash_const_iterator& __y) {
+ return __x.__node_ == __y.__node_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __hash_const_iterator& __x, const __hash_const_iterator& __y) {
+ return !(__x == __y);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_const_iterator(__next_pointer __node) _NOEXCEPT : __node_(__node) {}
+
+ template <class, class, class, class>
+ friend class __hash_table;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
+};
+
+template <class _NodePtr>
+class _LIBCPP_TEMPLATE_VIS __hash_local_iterator {
+ typedef __hash_node_types<_NodePtr> _NodeTypes;
+ typedef _NodePtr __node_pointer;
+ typedef typename _NodeTypes::__next_pointer __next_pointer;
+
+ __next_pointer __node_;
+ size_t __bucket_;
+ size_t __bucket_count_;
+
+public:
+ typedef forward_iterator_tag iterator_category;
+ typedef typename _NodeTypes::__node_value_type value_type;
+ typedef typename _NodeTypes::difference_type difference_type;
+ typedef value_type& reference;
+ typedef typename _NodeTypes::__node_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_local_iterator() _NOEXCEPT : __node_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to dereference a non-dereferenceable unordered container local_iterator");
+ return __node_->__upcast()->__get_value();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to dereference a non-dereferenceable unordered container local_iterator");
+ return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_local_iterator& operator++() {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to increment a non-incrementable unordered container local_iterator");
+ __node_ = __node_->__next_;
+ if (__node_ != nullptr && std::__constrain_hash(__node_->__hash(), __bucket_count_) != __bucket_)
+ __node_ = nullptr;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_local_iterator operator++(int) {
+ __hash_local_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __hash_local_iterator& __x, const __hash_local_iterator& __y) {
+ return __x.__node_ == __y.__node_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __hash_local_iterator& __x, const __hash_local_iterator& __y) {
+ return !(__x == __y);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_local_iterator(
+ __next_pointer __node, size_t __bucket, size_t __bucket_count) _NOEXCEPT
+ : __node_(__node),
+ __bucket_(__bucket),
+ __bucket_count_(__bucket_count) {
+ if (__node_ != nullptr)
+ __node_ = __node_->__next_;
+ }
+
+ template <class, class, class, class>
+ friend class __hash_table;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_map_iterator;
+};
+
+template <class _ConstNodePtr>
+class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator {
+ typedef __hash_node_types<_ConstNodePtr> _NodeTypes;
+ typedef _ConstNodePtr __node_pointer;
+ typedef typename _NodeTypes::__next_pointer __next_pointer;
+
+ __next_pointer __node_;
+ size_t __bucket_;
+ size_t __bucket_count_;
+
+ typedef pointer_traits<__node_pointer> __pointer_traits;
+ typedef typename __pointer_traits::element_type __node;
+ typedef __remove_const_t<__node> __non_const_node;
+ typedef __rebind_pointer_t<__node_pointer, __non_const_node> __non_const_node_pointer;
+
+public:
+ typedef __hash_local_iterator<__non_const_node_pointer> __non_const_iterator;
+
+ typedef forward_iterator_tag iterator_category;
+ typedef typename _NodeTypes::__node_value_type value_type;
+ typedef typename _NodeTypes::difference_type difference_type;
+ typedef const value_type& reference;
+ typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_const_local_iterator() _NOEXCEPT : __node_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI __hash_const_local_iterator(const __non_const_iterator& __x) _NOEXCEPT
+ : __node_(__x.__node_),
+ __bucket_(__x.__bucket_),
+ __bucket_count_(__x.__bucket_count_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
+ return __node_->__upcast()->__get_value();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
+ return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_const_local_iterator& operator++() {
+ _LIBCPP_ASSERT_NON_NULL(
+ __node_ != nullptr, "Attempted to increment a non-incrementable unordered container const_local_iterator");
+ __node_ = __node_->__next_;
+ if (__node_ != nullptr && std::__constrain_hash(__node_->__hash(), __bucket_count_) != __bucket_)
+ __node_ = nullptr;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_const_local_iterator operator++(int) {
+ __hash_const_local_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const __hash_const_local_iterator& __x, const __hash_const_local_iterator& __y) {
+ return __x.__node_ == __y.__node_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const __hash_const_local_iterator& __x, const __hash_const_local_iterator& __y) {
+ return !(__x == __y);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_const_local_iterator(
+ __next_pointer __node_ptr, size_t __bucket, size_t __bucket_count) _NOEXCEPT
+ : __node_(__node_ptr),
+ __bucket_(__bucket),
+ __bucket_count_(__bucket_count) {
+ if (__node_ != nullptr)
+ __node_ = __node_->__next_;
+ }
+
+ template <class, class, class, class>
+ friend class __hash_table;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
+};
+
+template <class _Alloc>
+class __bucket_list_deallocator {
+ typedef _Alloc allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+ typedef typename __alloc_traits::size_type size_type;
+
+ __compressed_pair<size_type, allocator_type> __data_;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __bucket_list_deallocator() _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
+ : __data_(0, __default_init_tag()) {}
+
+ _LIBCPP_HIDE_FROM_ABI __bucket_list_deallocator(const allocator_type& __a, size_type __size)
+ _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
+ : __data_(__size, __a) {}
+
+ _LIBCPP_HIDE_FROM_ABI __bucket_list_deallocator(__bucket_list_deallocator&& __x)
+ _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
+ : __data_(std::move(__x.__data_)) {
+ __x.size() = 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type& size() _NOEXCEPT { return __data_.first(); }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __data_.first(); }
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type& __alloc() _NOEXCEPT { return __data_.second(); }
+ _LIBCPP_HIDE_FROM_ABI const allocator_type& __alloc() const _NOEXCEPT { return __data_.second(); }
+
+ _LIBCPP_HIDE_FROM_ABI void operator()(pointer __p) _NOEXCEPT { __alloc_traits::deallocate(__alloc(), __p, size()); }
+};
+
+template <class _Alloc>
+class __hash_map_node_destructor;
+
+template <class _Alloc>
+class __hash_node_destructor {
+ typedef _Alloc allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+
+private:
+ typedef __hash_node_types<pointer> _NodeTypes;
+
+ allocator_type& __na_;
+
+public:
+ bool __value_constructed;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_node_destructor(__hash_node_destructor const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __hash_node_destructor& operator=(const __hash_node_destructor&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_node_destructor(allocator_type& __na, bool __constructed = false) _NOEXCEPT
+ : __na_(__na),
+ __value_constructed(__constructed) {}
+
+ _LIBCPP_HIDE_FROM_ABI void operator()(pointer __p) _NOEXCEPT {
+ if (__value_constructed) {
+ __alloc_traits::destroy(__na_, _NodeTypes::__get_ptr(__p->__get_value()));
+ std::__destroy_at(std::addressof(*__p));
+ }
+ if (__p)
+ __alloc_traits::deallocate(__na_, __p, 1);
+ }
+
+ template <class>
+ friend class __hash_map_node_destructor;
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _NodeType, class _Alloc>
+struct __generic_container_node_destructor;
+
+template <class _Tp, class _VoidPtr, class _Alloc>
+struct __generic_container_node_destructor<__hash_node<_Tp, _VoidPtr>, _Alloc> : __hash_node_destructor<_Alloc> {
+ using __hash_node_destructor<_Alloc>::__hash_node_destructor;
+};
+#endif
+
+template <class _Key, class _Hash, class _Equal>
+struct __enforce_unordered_container_requirements {
+#ifndef _LIBCPP_CXX03_LANG
+ static_assert(__check_hash_requirements<_Key, _Hash>::value,
+ "the specified hash does not meet the Hash requirements");
+ static_assert(is_copy_constructible<_Equal>::value, "the specified comparator is required to be copy constructible");
+#endif
+ typedef int type;
+};
+
+template <class _Key, class _Hash, class _Equal>
+#ifndef _LIBCPP_CXX03_LANG
+_LIBCPP_DIAGNOSE_WARNING(!__invokable<_Equal const&, _Key const&, _Key const&>::value,
+ "the specified comparator type does not provide a viable const call operator")
+_LIBCPP_DIAGNOSE_WARNING(!__invokable<_Hash const&, _Key const&>::value,
+ "the specified hash functor does not provide a viable const call operator")
+#endif
+ typename __enforce_unordered_container_requirements<_Key, _Hash, _Equal>::type
+ __diagnose_unordered_container_requirements(int);
+
+// This dummy overload is used so that the compiler won't emit a spurious
+// "no matching function for call to __diagnose_unordered_xxx" diagnostic
+// when the overload above causes a hard error.
+template <class _Key, class _Hash, class _Equal>
+int __diagnose_unordered_container_requirements(void*);
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+class __hash_table {
+public:
+ typedef _Tp value_type;
+ typedef _Hash hasher;
+ typedef _Equal key_equal;
+ typedef _Alloc allocator_type;
+
+private:
+ typedef allocator_traits<allocator_type> __alloc_traits;
+ typedef typename __make_hash_node_types<value_type, typename __alloc_traits::void_pointer>::type _NodeTypes;
+
+public:
+ typedef typename _NodeTypes::__node_value_type __node_value_type;
+ typedef typename _NodeTypes::__container_value_type __container_value_type;
+ typedef typename _NodeTypes::key_type key_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+#ifndef _LIBCPP_ABI_FIX_UNORDERED_CONTAINER_SIZE_TYPE
+ typedef typename __alloc_traits::size_type size_type;
+#else
+ typedef typename _NodeTypes::size_type size_type;
+#endif
+ typedef typename _NodeTypes::difference_type difference_type;
+
+public:
+ // Create __node
+
+ typedef typename _NodeTypes::__node_type __node;
+ typedef __rebind_alloc<__alloc_traits, __node> __node_allocator;
+ typedef allocator_traits<__node_allocator> __node_traits;
+ typedef typename _NodeTypes::__void_pointer __void_pointer;
+ typedef typename _NodeTypes::__node_pointer __node_pointer;
+ typedef typename _NodeTypes::__node_pointer __node_const_pointer;
+ typedef typename _NodeTypes::__node_base_type __first_node;
+ typedef typename _NodeTypes::__node_base_pointer __node_base_pointer;
+ typedef typename _NodeTypes::__next_pointer __next_pointer;
+
+private:
+ // check for sane allocator pointer rebinding semantics. Rebinding the
+ // allocator for a new pointer type should be exactly the same as rebinding
+ // the pointer using 'pointer_traits'.
+ static_assert(is_same<__node_pointer, typename __node_traits::pointer>::value,
+ "Allocator does not rebind pointers in a sane manner.");
+ typedef __rebind_alloc<__node_traits, __first_node> __node_base_allocator;
+ typedef allocator_traits<__node_base_allocator> __node_base_traits;
+ static_assert(is_same<__node_base_pointer, typename __node_base_traits::pointer>::value,
+ "Allocator does not rebind pointers in a sane manner.");
+
+private:
+ typedef __rebind_alloc<__node_traits, __next_pointer> __pointer_allocator;
+ typedef __bucket_list_deallocator<__pointer_allocator> __bucket_list_deleter;
+ typedef unique_ptr<__next_pointer[], __bucket_list_deleter> __bucket_list;
+ typedef allocator_traits<__pointer_allocator> __pointer_alloc_traits;
+ typedef typename __bucket_list_deleter::pointer __node_pointer_pointer;
+
+ // --- Member data begin ---
+ __bucket_list __bucket_list_;
+ __compressed_pair<__first_node, __node_allocator> __p1_;
+ __compressed_pair<size_type, hasher> __p2_;
+ __compressed_pair<float, key_equal> __p3_;
+ // --- Member data end ---
+
+ _LIBCPP_HIDE_FROM_ABI size_type& size() _NOEXCEPT { return __p2_.first(); }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __p2_.first(); }
+
+ _LIBCPP_HIDE_FROM_ABI hasher& hash_function() _NOEXCEPT { return __p2_.second(); }
+ _LIBCPP_HIDE_FROM_ABI const hasher& hash_function() const _NOEXCEPT { return __p2_.second(); }
+
+ _LIBCPP_HIDE_FROM_ABI float& max_load_factor() _NOEXCEPT { return __p3_.first(); }
+ _LIBCPP_HIDE_FROM_ABI float max_load_factor() const _NOEXCEPT { return __p3_.first(); }
+
+ _LIBCPP_HIDE_FROM_ABI key_equal& key_eq() _NOEXCEPT { return __p3_.second(); }
+ _LIBCPP_HIDE_FROM_ABI const key_equal& key_eq() const _NOEXCEPT { return __p3_.second(); }
+
+ _LIBCPP_HIDE_FROM_ABI __node_allocator& __node_alloc() _NOEXCEPT { return __p1_.second(); }
+ _LIBCPP_HIDE_FROM_ABI const __node_allocator& __node_alloc() const _NOEXCEPT { return __p1_.second(); }
+
+public:
+ typedef __hash_iterator<__node_pointer> iterator;
+ typedef __hash_const_iterator<__node_pointer> const_iterator;
+ typedef __hash_local_iterator<__node_pointer> local_iterator;
+ typedef __hash_const_local_iterator<__node_pointer> const_local_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_table() _NOEXCEPT_(
+ is_nothrow_default_constructible<__bucket_list>::value&& is_nothrow_default_constructible<__first_node>::value&&
+ is_nothrow_default_constructible<__node_allocator>::value&& is_nothrow_default_constructible<hasher>::value&&
+ is_nothrow_default_constructible<key_equal>::value);
+ _LIBCPP_HIDE_FROM_ABI __hash_table(const hasher& __hf, const key_equal& __eql);
+ _LIBCPP_HIDE_FROM_ABI __hash_table(const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_table(const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI __hash_table(const __hash_table& __u);
+ _LIBCPP_HIDE_FROM_ABI __hash_table(const __hash_table& __u, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI __hash_table(__hash_table&& __u) _NOEXCEPT_(
+ is_nothrow_move_constructible<__bucket_list>::value&& is_nothrow_move_constructible<__first_node>::value&&
+ is_nothrow_move_constructible<__node_allocator>::value&& is_nothrow_move_constructible<hasher>::value&&
+ is_nothrow_move_constructible<key_equal>::value);
+ _LIBCPP_HIDE_FROM_ABI __hash_table(__hash_table&& __u, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI ~__hash_table();
+
+ _LIBCPP_HIDE_FROM_ABI __hash_table& operator=(const __hash_table& __u);
+ _LIBCPP_HIDE_FROM_ABI __hash_table& operator=(__hash_table&& __u)
+ _NOEXCEPT_(__node_traits::propagate_on_container_move_assignment::value&&
+ is_nothrow_move_assignable<__node_allocator>::value&& is_nothrow_move_assignable<hasher>::value&&
+ is_nothrow_move_assignable<key_equal>::value);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void __assign_unique(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void __assign_multi(_InputIterator __first, _InputIterator __last);
+
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT {
+ return std::min<size_type>(__node_traits::max_size(__node_alloc()), numeric_limits<difference_type >::max());
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI __next_pointer __node_insert_multi_prepare(size_t __cp_hash, value_type& __cp_val);
+ _LIBCPP_HIDE_FROM_ABI void __node_insert_multi_perform(__node_pointer __cp, __next_pointer __pn) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI __next_pointer __node_insert_unique_prepare(size_t __nd_hash, value_type& __nd_val);
+ _LIBCPP_HIDE_FROM_ABI void __node_insert_unique_perform(__node_pointer __ptr) _NOEXCEPT;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __node_insert_unique(__node_pointer __nd);
+ _LIBCPP_HIDE_FROM_ABI iterator __node_insert_multi(__node_pointer __nd);
+ _LIBCPP_HIDE_FROM_ABI iterator __node_insert_multi(const_iterator __p, __node_pointer __nd);
+
+ template <class _Key, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_key_args(_Key const& __k, _Args&&... __args);
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_impl(_Args&&... __args);
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique(_Pp&& __x) {
+ return __emplace_unique_extract_key(std::forward<_Pp>(__x), __can_extract_key<_Pp, key_type>());
+ }
+
+ template <class _First,
+ class _Second,
+ __enable_if_t<__can_extract_map_key<_First, key_type, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique(_First&& __f, _Second&& __s) {
+ return __emplace_unique_key_args(__f, std::forward<_First>(__f), std::forward<_Second>(__s));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique(_Args&&... __args) {
+ return __emplace_unique_impl(std::forward<_Args>(__args)...);
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_extract_key(_Pp&& __x, __extract_key_fail_tag) {
+ return __emplace_unique_impl(std::forward<_Pp>(__x));
+ }
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_extract_key(_Pp&& __x, __extract_key_self_tag) {
+ return __emplace_unique_key_args(__x, std::forward<_Pp>(__x));
+ }
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_extract_key(_Pp&& __x, __extract_key_first_tag) {
+ return __emplace_unique_key_args(__x.first, std::forward<_Pp>(__x));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator __emplace_multi(_Args&&... __args);
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator __emplace_hint_multi(const_iterator __p, _Args&&... __args);
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __insert_unique(__container_value_type&& __x) {
+ return __emplace_unique_key_args(_NodeTypes::__get_key(__x), std::move(__x));
+ }
+
+ template <class _Pp, __enable_if_t<!__is_same_uncvref<_Pp, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __insert_unique(_Pp&& __x) {
+ return __emplace_unique(std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_multi(_Pp&& __x) {
+ return __emplace_multi(std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_multi(const_iterator __p, _Pp&& __x) {
+ return __emplace_hint_multi(__p, std::forward<_Pp>(__x));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __insert_unique(const __container_value_type& __x) {
+ return __emplace_unique_key_args(_NodeTypes::__get_key(__x), __x);
+ }
+
+#if _LIBCPP_STD_VER >= 17
+ template <class _NodeHandle, class _InsertReturnType>
+ _LIBCPP_HIDE_FROM_ABI _InsertReturnType __node_handle_insert_unique(_NodeHandle&& __nh);
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI iterator __node_handle_insert_unique(const_iterator __hint, _NodeHandle&& __nh);
+ template <class _Table>
+ _LIBCPP_HIDE_FROM_ABI void __node_handle_merge_unique(_Table& __source);
+
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI iterator __node_handle_insert_multi(_NodeHandle&& __nh);
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI iterator __node_handle_insert_multi(const_iterator __hint, _NodeHandle&& __nh);
+ template <class _Table>
+ _LIBCPP_HIDE_FROM_ABI void __node_handle_merge_multi(_Table& __source);
+
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI _NodeHandle __node_handle_extract(key_type const& __key);
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI _NodeHandle __node_handle_extract(const_iterator __it);
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI void __rehash_unique(size_type __n) { __rehash<true>(__n); }
+ _LIBCPP_HIDE_FROM_ABI void __rehash_multi(size_type __n) { __rehash<false>(__n); }
+ _LIBCPP_HIDE_FROM_ABI void __reserve_unique(size_type __n) {
+ __rehash_unique(static_cast<size_type>(std::ceil(__n / max_load_factor())));
+ }
+ _LIBCPP_HIDE_FROM_ABI void __reserve_multi(size_type __n) {
+ __rehash_multi(static_cast<size_type>(std::ceil(__n / max_load_factor())));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const _NOEXCEPT { return __bucket_list_.get_deleter().size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT;
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type bucket(const _Key& __k) const {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ bucket_count() > 0, "unordered container::bucket(key) called when bucket_count() == 0");
+ return std::__constrain_hash(hash_function()(__k), bucket_count());
+ }
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _Key& __x);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _Key& __x) const;
+
+ typedef __hash_node_destructor<__node_allocator> _Dp;
+ typedef unique_ptr<__node, _Dp> __node_holder;
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p);
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type __erase_unique(const _Key& __k);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type __erase_multi(const _Key& __k);
+ _LIBCPP_HIDE_FROM_ABI __node_holder remove(const_iterator __p) _NOEXCEPT;
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type __count_unique(const _Key& __k) const;
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type __count_multi(const _Key& __k) const;
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> __equal_range_unique(const _Key& __k);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> __equal_range_unique(const _Key& __k) const;
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> __equal_range_multi(const _Key& __k);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> __equal_range_multi(const _Key& __k) const;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(__hash_table& __u)
+#if _LIBCPP_STD_VER <= 11
+ _NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal> &&
+ (!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value ||
+ __is_nothrow_swappable_v<__pointer_allocator>) &&
+ (!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>));
+#else
+ _NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal>);
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const _NOEXCEPT { return max_size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_size(size_type __n) const;
+ _LIBCPP_HIDE_FROM_ABI float load_factor() const _NOEXCEPT {
+ size_type __bc = bucket_count();
+ return __bc != 0 ? (float)size() / __bc : 0.f;
+ }
+ _LIBCPP_HIDE_FROM_ABI void max_load_factor(float __mlf) _NOEXCEPT {
+ // While passing a non-positive load factor is undefined behavior, in practice the result will be benign (the
+ // call will be equivalent to `max_load_factor(load_factor())`, which is also the case for passing a valid value
+ // less than the current `load_factor`).
+ _LIBCPP_ASSERT_PEDANTIC(__mlf > 0, "unordered container::max_load_factor(lf) called with lf <= 0");
+ max_load_factor() = std::max(__mlf, load_factor());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI local_iterator begin(size_type __n) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n < bucket_count(), "unordered container::begin(n) called with n >= bucket_count()");
+ return local_iterator(__bucket_list_[__n], __n, bucket_count());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI local_iterator end(size_type __n) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n < bucket_count(), "unordered container::end(n) called with n >= bucket_count()");
+ return local_iterator(nullptr, __n, bucket_count());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cbegin(size_type __n) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n < bucket_count(), "unordered container::cbegin(n) called with n >= bucket_count()");
+ return const_local_iterator(__bucket_list_[__n], __n, bucket_count());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cend(size_type __n) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n < bucket_count(), "unordered container::cend(n) called with n >= bucket_count()");
+ return const_local_iterator(nullptr, __n, bucket_count());
+ }
+
+private:
+ template <bool _UniqueKeys>
+ _LIBCPP_HIDE_FROM_ABI void __rehash(size_type __n);
+ template <bool _UniqueKeys>
+ _LIBCPP_HIDE_FROM_ABI void __do_rehash(size_type __n);
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI __node_holder __construct_node(_Args&&... __args);
+
+ template <class _First, class... _Rest>
+ _LIBCPP_HIDE_FROM_ABI __node_holder __construct_node_hash(size_t __hash, _First&& __f, _Rest&&... __rest);
+
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __hash_table& __u) {
+ __copy_assign_alloc(__u, integral_constant<bool, __node_traits::propagate_on_container_copy_assignment::value>());
+ }
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __hash_table& __u, true_type);
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __hash_table&, false_type) {}
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(__hash_table& __u, false_type);
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(__hash_table& __u, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value&& is_nothrow_move_assignable<hasher>::value&&
+ is_nothrow_move_assignable<key_equal>::value);
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__hash_table& __u) _NOEXCEPT_(
+ !__node_traits::propagate_on_container_move_assignment::value ||
+ (is_nothrow_move_assignable<__pointer_allocator>::value && is_nothrow_move_assignable<__node_allocator>::value)) {
+ __move_assign_alloc(__u, integral_constant<bool, __node_traits::propagate_on_container_move_assignment::value>());
+ }
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__hash_table& __u, true_type) _NOEXCEPT_(
+ is_nothrow_move_assignable<__pointer_allocator>::value&& is_nothrow_move_assignable<__node_allocator>::value) {
+ __bucket_list_.get_deleter().__alloc() = std::move(__u.__bucket_list_.get_deleter().__alloc());
+ __node_alloc() = std::move(__u.__node_alloc());
+ }
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__hash_table&, false_type) _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI void __deallocate_node(__next_pointer __np) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI __next_pointer __detach() _NOEXCEPT;
+
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
+};
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+inline __hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table() _NOEXCEPT_(
+ is_nothrow_default_constructible<__bucket_list>::value&& is_nothrow_default_constructible<__first_node>::value&&
+ is_nothrow_default_constructible<__node_allocator>::value&& is_nothrow_default_constructible<hasher>::value&&
+ is_nothrow_default_constructible<key_equal>::value)
+ : __p2_(0, __default_init_tag()), __p3_(1.0f, __default_init_tag()) {}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+inline __hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const hasher& __hf, const key_equal& __eql)
+ : __bucket_list_(nullptr, __bucket_list_deleter()), __p1_(), __p2_(0, __hf), __p3_(1.0f, __eql) {}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(
+ const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
+ __p1_(__default_init_tag(), __node_allocator(__a)),
+ __p2_(0, __hf),
+ __p3_(1.0f, __eql) {}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const allocator_type& __a)
+ : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
+ __p1_(__default_init_tag(), __node_allocator(__a)),
+ __p2_(0, __default_init_tag()),
+ __p3_(1.0f, __default_init_tag()) {}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const __hash_table& __u)
+ : __bucket_list_(nullptr,
+ __bucket_list_deleter(allocator_traits<__pointer_allocator>::select_on_container_copy_construction(
+ __u.__bucket_list_.get_deleter().__alloc()),
+ 0)),
+ __p1_(__default_init_tag(),
+ allocator_traits<__node_allocator>::select_on_container_copy_construction(__u.__node_alloc())),
+ __p2_(0, __u.hash_function()),
+ __p3_(__u.__p3_) {}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const __hash_table& __u, const allocator_type& __a)
+ : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
+ __p1_(__default_init_tag(), __node_allocator(__a)),
+ __p2_(0, __u.hash_function()),
+ __p3_(__u.__p3_) {}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u) _NOEXCEPT_(
+ is_nothrow_move_constructible<__bucket_list>::value&& is_nothrow_move_constructible<__first_node>::value&&
+ is_nothrow_move_constructible<__node_allocator>::value&& is_nothrow_move_constructible<hasher>::value&&
+ is_nothrow_move_constructible<key_equal>::value)
+ : __bucket_list_(std::move(__u.__bucket_list_)),
+ __p1_(std::move(__u.__p1_)),
+ __p2_(std::move(__u.__p2_)),
+ __p3_(std::move(__u.__p3_)) {
+ if (size() > 0) {
+ __bucket_list_[std::__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] = __p1_.first().__ptr();
+ __u.__p1_.first().__next_ = nullptr;
+ __u.size() = 0;
+ }
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u, const allocator_type& __a)
+ : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
+ __p1_(__default_init_tag(), __node_allocator(__a)),
+ __p2_(0, std::move(__u.hash_function())),
+ __p3_(std::move(__u.__p3_)) {
+ if (__a == allocator_type(__u.__node_alloc())) {
+ __bucket_list_.reset(__u.__bucket_list_.release());
+ __bucket_list_.get_deleter().size() = __u.__bucket_list_.get_deleter().size();
+ __u.__bucket_list_.get_deleter().size() = 0;
+ if (__u.size() > 0) {
+ __p1_.first().__next_ = __u.__p1_.first().__next_;
+ __u.__p1_.first().__next_ = nullptr;
+ __bucket_list_[std::__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] = __p1_.first().__ptr();
+ size() = __u.size();
+ __u.size() = 0;
+ }
+ }
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::~__hash_table() {
+#if defined(_LIBCPP_CXX03_LANG)
+ static_assert(is_copy_constructible<key_equal>::value, "Predicate must be copy-constructible.");
+ static_assert(is_copy_constructible<hasher>::value, "Hasher must be copy-constructible.");
+#endif
+
+ __deallocate_node(__p1_.first().__next_);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__copy_assign_alloc(const __hash_table& __u, true_type) {
+ if (__node_alloc() != __u.__node_alloc()) {
+ clear();
+ __bucket_list_.reset();
+ __bucket_list_.get_deleter().size() = 0;
+ }
+ __bucket_list_.get_deleter().__alloc() = __u.__bucket_list_.get_deleter().__alloc();
+ __node_alloc() = __u.__node_alloc();
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>& __hash_table<_Tp, _Hash, _Equal, _Alloc>::operator=(const __hash_table& __u) {
+ if (this != std::addressof(__u)) {
+ __copy_assign_alloc(__u);
+ hash_function() = __u.hash_function();
+ key_eq() = __u.key_eq();
+ max_load_factor() = __u.max_load_factor();
+ __assign_multi(__u.begin(), __u.end());
+ }
+ return *this;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__deallocate_node(__next_pointer __np) _NOEXCEPT {
+ __node_allocator& __na = __node_alloc();
+ while (__np != nullptr) {
+ __next_pointer __next = __np->__next_;
+ __node_pointer __real_np = __np->__upcast();
+ __node_traits::destroy(__na, _NodeTypes::__get_ptr(__real_np->__get_value()));
+ std::__destroy_at(std::addressof(*__real_np));
+ __node_traits::deallocate(__na, __real_np, 1);
+ __np = __next;
+ }
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__next_pointer
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__detach() _NOEXCEPT {
+ size_type __bc = bucket_count();
+ for (size_type __i = 0; __i < __bc; ++__i)
+ __bucket_list_[__i] = nullptr;
+ size() = 0;
+ __next_pointer __cache = __p1_.first().__next_;
+ __p1_.first().__next_ = nullptr;
+ return __cache;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(__hash_table& __u, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value&& is_nothrow_move_assignable<hasher>::value&&
+ is_nothrow_move_assignable<key_equal>::value) {
+ clear();
+ __bucket_list_.reset(__u.__bucket_list_.release());
+ __bucket_list_.get_deleter().size() = __u.__bucket_list_.get_deleter().size();
+ __u.__bucket_list_.get_deleter().size() = 0;
+ __move_assign_alloc(__u);
+ size() = __u.size();
+ hash_function() = std::move(__u.hash_function());
+ max_load_factor() = __u.max_load_factor();
+ key_eq() = std::move(__u.key_eq());
+ __p1_.first().__next_ = __u.__p1_.first().__next_;
+ if (size() > 0) {
+ __bucket_list_[std::__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] = __p1_.first().__ptr();
+ __u.__p1_.first().__next_ = nullptr;
+ __u.size() = 0;
+ }
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(__hash_table& __u, false_type) {
+ if (__node_alloc() == __u.__node_alloc())
+ __move_assign(__u, true_type());
+ else {
+ hash_function() = std::move(__u.hash_function());
+ key_eq() = std::move(__u.key_eq());
+ max_load_factor() = __u.max_load_factor();
+ if (bucket_count() != 0) {
+ __next_pointer __cache = __detach();
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ const_iterator __i = __u.begin();
+ while (__cache != nullptr && __u.size() != 0) {
+ __cache->__upcast()->__get_value() = std::move(__u.remove(__i++)->__get_value());
+ __next_pointer __next = __cache->__next_;
+ __node_insert_multi(__cache->__upcast());
+ __cache = __next;
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __deallocate_node(__cache);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __deallocate_node(__cache);
+ }
+ const_iterator __i = __u.begin();
+ while (__u.size() != 0) {
+ __node_holder __h = __construct_node(_NodeTypes::__move(__u.remove(__i++)->__get_value()));
+ __node_insert_multi(__h.get());
+ __h.release();
+ }
+ }
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+inline __hash_table<_Tp, _Hash, _Equal, _Alloc>&
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::operator=(__hash_table&& __u) _NOEXCEPT_(
+ __node_traits::propagate_on_container_move_assignment::value&& is_nothrow_move_assignable<__node_allocator>::value&&
+ is_nothrow_move_assignable<hasher>::value&& is_nothrow_move_assignable<key_equal>::value) {
+ __move_assign(__u, integral_constant<bool, __node_traits::propagate_on_container_move_assignment::value>());
+ return *this;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _InputIterator>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__assign_unique(_InputIterator __first, _InputIterator __last) {
+ typedef iterator_traits<_InputIterator> _ITraits;
+ typedef typename _ITraits::value_type _ItValueType;
+ static_assert(is_same<_ItValueType, __container_value_type>::value,
+ "__assign_unique may only be called with the containers value type");
+
+ if (bucket_count() != 0) {
+ __next_pointer __cache = __detach();
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (; __cache != nullptr && __first != __last; ++__first) {
+ __cache->__upcast()->__get_value() = *__first;
+ __next_pointer __next = __cache->__next_;
+ __node_insert_unique(__cache->__upcast());
+ __cache = __next;
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __deallocate_node(__cache);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __deallocate_node(__cache);
+ }
+ for (; __first != __last; ++__first)
+ __insert_unique(*__first);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _InputIterator>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__assign_multi(_InputIterator __first, _InputIterator __last) {
+ typedef iterator_traits<_InputIterator> _ITraits;
+ typedef typename _ITraits::value_type _ItValueType;
+ static_assert(
+ (is_same<_ItValueType, __container_value_type>::value || is_same<_ItValueType, __node_value_type>::value),
+ "__assign_multi may only be called with the containers value type"
+ " or the nodes value type");
+ if (bucket_count() != 0) {
+ __next_pointer __cache = __detach();
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (; __cache != nullptr && __first != __last; ++__first) {
+ __cache->__upcast()->__get_value() = *__first;
+ __next_pointer __next = __cache->__next_;
+ __node_insert_multi(__cache->__upcast());
+ __cache = __next;
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __deallocate_node(__cache);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __deallocate_node(__cache);
+ }
+ for (; __first != __last; ++__first)
+ __insert_multi(_NodeTypes::__get_value(*__first));
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+inline typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::begin() _NOEXCEPT {
+ return iterator(__p1_.first().__next_);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+inline typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::end() _NOEXCEPT {
+ return iterator(nullptr);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+inline typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::begin() const _NOEXCEPT {
+ return const_iterator(__p1_.first().__next_);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+inline typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::end() const _NOEXCEPT {
+ return const_iterator(nullptr);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::clear() _NOEXCEPT {
+ if (size() > 0) {
+ __deallocate_node(__p1_.first().__next_);
+ __p1_.first().__next_ = nullptr;
+ size_type __bc = bucket_count();
+ for (size_type __i = 0; __i < __bc; ++__i)
+ __bucket_list_[__i] = nullptr;
+ size() = 0;
+ }
+}
+
+// Prepare the container for an insertion of the value __value with the hash
+// __hash. This does a lookup into the container to see if __value is already
+// present, and performs a rehash if necessary. Returns a pointer to the
+// existing element if it exists, otherwise nullptr.
+//
+// Note that this function does forward exceptions if key_eq() throws, and never
+// mutates __value or actually inserts into the map.
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__next_pointer
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique_prepare(size_t __hash, value_type& __value) {
+ size_type __bc = bucket_count();
+
+ if (__bc != 0) {
+ size_t __chash = std::__constrain_hash(__hash, __bc);
+ __next_pointer __ndptr = __bucket_list_[__chash];
+ if (__ndptr != nullptr) {
+ for (__ndptr = __ndptr->__next_;
+ __ndptr != nullptr &&
+ (__ndptr->__hash() == __hash || std::__constrain_hash(__ndptr->__hash(), __bc) == __chash);
+ __ndptr = __ndptr->__next_) {
+ if ((__ndptr->__hash() == __hash) && key_eq()(__ndptr->__upcast()->__get_value(), __value))
+ return __ndptr;
+ }
+ }
+ }
+ if (size() + 1 > __bc * max_load_factor() || __bc == 0) {
+ __rehash_unique(std::max<size_type>(
+ 2 * __bc + !std::__is_hash_power2(__bc), size_type(std::ceil(float(size() + 1) / max_load_factor()))));
+ }
+ return nullptr;
+}
+
+// Insert the node __nd into the container by pushing it into the right bucket,
+// and updating size(). Assumes that __nd->__hash is up-to-date, and that
+// rehashing has already occurred and that no element with the same key exists
+// in the map.
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI void
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique_perform(__node_pointer __nd) _NOEXCEPT {
+ size_type __bc = bucket_count();
+ size_t __chash = std::__constrain_hash(__nd->__hash(), __bc);
+ // insert_after __bucket_list_[__chash], or __first_node if bucket is null
+ __next_pointer __pn = __bucket_list_[__chash];
+ if (__pn == nullptr) {
+ __pn = __p1_.first().__ptr();
+ __nd->__next_ = __pn->__next_;
+ __pn->__next_ = __nd->__ptr();
+ // fix up __bucket_list_
+ __bucket_list_[__chash] = __pn;
+ if (__nd->__next_ != nullptr)
+ __bucket_list_[std::__constrain_hash(__nd->__next_->__hash(), __bc)] = __nd->__ptr();
+ } else {
+ __nd->__next_ = __pn->__next_;
+ __pn->__next_ = __nd->__ptr();
+ }
+ ++size();
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique(__node_pointer __nd) {
+ __nd->__hash_ = hash_function()(__nd->__get_value());
+ __next_pointer __existing_node = __node_insert_unique_prepare(__nd->__hash(), __nd->__get_value());
+
+ // Insert the node, unless it already exists in the container.
+ bool __inserted = false;
+ if (__existing_node == nullptr) {
+ __node_insert_unique_perform(__nd);
+ __existing_node = __nd->__ptr();
+ __inserted = true;
+ }
+ return pair<iterator, bool>(iterator(__existing_node), __inserted);
+}
+
+// Prepare the container for an insertion of the value __cp_val with the hash
+// __cp_hash. This does a lookup into the container to see if __cp_value is
+// already present, and performs a rehash if necessary. Returns a pointer to the
+// last occurrence of __cp_val in the map.
+//
+// Note that this function does forward exceptions if key_eq() throws, and never
+// mutates __value or actually inserts into the map.
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__next_pointer
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi_prepare(size_t __cp_hash, value_type& __cp_val) {
+ size_type __bc = bucket_count();
+ if (size() + 1 > __bc * max_load_factor() || __bc == 0) {
+ __rehash_multi(std::max<size_type>(
+ 2 * __bc + !std::__is_hash_power2(__bc), size_type(std::ceil(float(size() + 1) / max_load_factor()))));
+ __bc = bucket_count();
+ }
+ size_t __chash = std::__constrain_hash(__cp_hash, __bc);
+ __next_pointer __pn = __bucket_list_[__chash];
+ if (__pn != nullptr) {
+ for (bool __found = false;
+ __pn->__next_ != nullptr && std::__constrain_hash(__pn->__next_->__hash(), __bc) == __chash;
+ __pn = __pn->__next_) {
+ // __found key_eq() action
+ // false false loop
+ // true true loop
+ // false true set __found to true
+ // true false break
+ if (__found !=
+ (__pn->__next_->__hash() == __cp_hash && key_eq()(__pn->__next_->__upcast()->__get_value(), __cp_val))) {
+ if (!__found)
+ __found = true;
+ else
+ break;
+ }
+ }
+ }
+ return __pn;
+}
+
+// Insert the node __cp into the container after __pn (which is the last node in
+// the bucket that compares equal to __cp). Rehashing, and checking for
+// uniqueness has already been performed (in __node_insert_multi_prepare), so
+// all we need to do is update the bucket and size(). Assumes that __cp->__hash
+// is up-to-date.
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi_perform(
+ __node_pointer __cp, __next_pointer __pn) _NOEXCEPT {
+ size_type __bc = bucket_count();
+ size_t __chash = std::__constrain_hash(__cp->__hash_, __bc);
+ if (__pn == nullptr) {
+ __pn = __p1_.first().__ptr();
+ __cp->__next_ = __pn->__next_;
+ __pn->__next_ = __cp->__ptr();
+ // fix up __bucket_list_
+ __bucket_list_[__chash] = __pn;
+ if (__cp->__next_ != nullptr)
+ __bucket_list_[std::__constrain_hash(__cp->__next_->__hash(), __bc)] = __cp->__ptr();
+ } else {
+ __cp->__next_ = __pn->__next_;
+ __pn->__next_ = __cp->__ptr();
+ if (__cp->__next_ != nullptr) {
+ size_t __nhash = std::__constrain_hash(__cp->__next_->__hash(), __bc);
+ if (__nhash != __chash)
+ __bucket_list_[__nhash] = __cp->__ptr();
+ }
+ }
+ ++size();
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(__node_pointer __cp) {
+ __cp->__hash_ = hash_function()(__cp->__get_value());
+ __next_pointer __pn = __node_insert_multi_prepare(__cp->__hash(), __cp->__get_value());
+ __node_insert_multi_perform(__cp, __pn);
+
+ return iterator(__cp->__ptr());
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(const_iterator __p, __node_pointer __cp) {
+ if (__p != end() && key_eq()(*__p, __cp->__get_value())) {
+ __next_pointer __np = __p.__node_;
+ __cp->__hash_ = __np->__hash();
+ size_type __bc = bucket_count();
+ if (size() + 1 > __bc * max_load_factor() || __bc == 0) {
+ __rehash_multi(std::max<size_type>(
+ 2 * __bc + !std::__is_hash_power2(__bc), size_type(std::ceil(float(size() + 1) / max_load_factor()))));
+ __bc = bucket_count();
+ }
+ size_t __chash = std::__constrain_hash(__cp->__hash_, __bc);
+ __next_pointer __pp = __bucket_list_[__chash];
+ while (__pp->__next_ != __np)
+ __pp = __pp->__next_;
+ __cp->__next_ = __np;
+ __pp->__next_ = static_cast<__next_pointer>(__cp);
+ ++size();
+ return iterator(static_cast<__next_pointer>(__cp));
+ }
+ return __node_insert_multi(__cp);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key, class... _Args>
+pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_key_args(_Key const& __k, _Args&&... __args) {
+ size_t __hash = hash_function()(__k);
+ size_type __bc = bucket_count();
+ bool __inserted = false;
+ __next_pointer __nd;
+ size_t __chash;
+ if (__bc != 0) {
+ __chash = std::__constrain_hash(__hash, __bc);
+ __nd = __bucket_list_[__chash];
+ if (__nd != nullptr) {
+ for (__nd = __nd->__next_;
+ __nd != nullptr && (__nd->__hash() == __hash || std::__constrain_hash(__nd->__hash(), __bc) == __chash);
+ __nd = __nd->__next_) {
+ if ((__nd->__hash() == __hash) && key_eq()(__nd->__upcast()->__get_value(), __k))
+ goto __done;
+ }
+ }
+ }
+ {
+ __node_holder __h = __construct_node_hash(__hash, std::forward<_Args>(__args)...);
+ if (size() + 1 > __bc * max_load_factor() || __bc == 0) {
+ __rehash_unique(std::max<size_type>(
+ 2 * __bc + !std::__is_hash_power2(__bc), size_type(std::ceil(float(size() + 1) / max_load_factor()))));
+ __bc = bucket_count();
+ __chash = std::__constrain_hash(__hash, __bc);
+ }
+ // insert_after __bucket_list_[__chash], or __first_node if bucket is null
+ __next_pointer __pn = __bucket_list_[__chash];
+ if (__pn == nullptr) {
+ __pn = __p1_.first().__ptr();
+ __h->__next_ = __pn->__next_;
+ __pn->__next_ = __h.get()->__ptr();
+ // fix up __bucket_list_
+ __bucket_list_[__chash] = __pn;
+ if (__h->__next_ != nullptr)
+ __bucket_list_[std::__constrain_hash(__h->__next_->__hash(), __bc)] = __h.get()->__ptr();
+ } else {
+ __h->__next_ = __pn->__next_;
+ __pn->__next_ = static_cast<__next_pointer>(__h.get());
+ }
+ __nd = static_cast<__next_pointer>(__h.release());
+ // increment size
+ ++size();
+ __inserted = true;
+ }
+__done:
+ return pair<iterator, bool>(iterator(__nd), __inserted);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class... _Args>
+pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_impl(_Args&&... __args) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ pair<iterator, bool> __r = __node_insert_unique(__h.get());
+ if (__r.second)
+ __h.release();
+ return __r;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class... _Args>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_multi(_Args&&... __args) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ iterator __r = __node_insert_multi(__h.get());
+ __h.release();
+ return __r;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class... _Args>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_hint_multi(const_iterator __p, _Args&&... __args) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ iterator __r = __node_insert_multi(__p, __h.get());
+ __h.release();
+ return __r;
+}
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _NodeHandle, class _InsertReturnType>
+_LIBCPP_HIDE_FROM_ABI _InsertReturnType
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_handle_insert_unique(_NodeHandle&& __nh) {
+ if (__nh.empty())
+ return _InsertReturnType{end(), false, _NodeHandle()};
+ pair<iterator, bool> __result = __node_insert_unique(__nh.__ptr_);
+ if (__result.second)
+ __nh.__release_ptr();
+ return _InsertReturnType{__result.first, __result.second, std::move(__nh)};
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_handle_insert_unique(const_iterator, _NodeHandle&& __nh) {
+ if (__nh.empty())
+ return end();
+ pair<iterator, bool> __result = __node_insert_unique(__nh.__ptr_);
+ if (__result.second)
+ __nh.__release_ptr();
+ return __result.first;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI _NodeHandle
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_handle_extract(key_type const& __key) {
+ iterator __i = find(__key);
+ if (__i == end())
+ return _NodeHandle();
+ return __node_handle_extract<_NodeHandle>(__i);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI _NodeHandle __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_handle_extract(const_iterator __p) {
+ allocator_type __alloc(__node_alloc());
+ return _NodeHandle(remove(__p).release(), __alloc);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Table>
+_LIBCPP_HIDE_FROM_ABI void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_handle_merge_unique(_Table& __source) {
+ static_assert(is_same<__node, typename _Table::__node>::value, "");
+
+ for (typename _Table::iterator __it = __source.begin(); __it != __source.end();) {
+ __node_pointer __src_ptr = __it.__node_->__upcast();
+ size_t __hash = hash_function()(__src_ptr->__get_value());
+ __next_pointer __existing_node = __node_insert_unique_prepare(__hash, __src_ptr->__get_value());
+ auto __prev_iter = __it++;
+ if (__existing_node == nullptr) {
+ (void)__source.remove(__prev_iter).release();
+ __src_ptr->__hash_ = __hash;
+ __node_insert_unique_perform(__src_ptr);
+ }
+ }
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_handle_insert_multi(_NodeHandle&& __nh) {
+ if (__nh.empty())
+ return end();
+ iterator __result = __node_insert_multi(__nh.__ptr_);
+ __nh.__release_ptr();
+ return __result;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_handle_insert_multi(const_iterator __hint, _NodeHandle&& __nh) {
+ if (__nh.empty())
+ return end();
+ iterator __result = __node_insert_multi(__hint, __nh.__ptr_);
+ __nh.__release_ptr();
+ return __result;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Table>
+_LIBCPP_HIDE_FROM_ABI void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_handle_merge_multi(_Table& __source) {
+ static_assert(is_same<typename _Table::__node, __node>::value, "");
+
+ for (typename _Table::iterator __it = __source.begin(); __it != __source.end();) {
+ __node_pointer __src_ptr = __it.__node_->__upcast();
+ size_t __src_hash = hash_function()(__src_ptr->__get_value());
+ __next_pointer __pn = __node_insert_multi_prepare(__src_hash, __src_ptr->__get_value());
+ (void)__source.remove(__it++).release();
+ __src_ptr->__hash_ = __src_hash;
+ __node_insert_multi_perform(__src_ptr, __pn);
+ }
+}
+#endif // _LIBCPP_STD_VER >= 17
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <bool _UniqueKeys>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__rehash(size_type __n) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK {
+ if (__n == 1)
+ __n = 2;
+ else if (__n & (__n - 1))
+ __n = std::__next_prime(__n);
+ size_type __bc = bucket_count();
+ if (__n > __bc)
+ __do_rehash<_UniqueKeys>(__n);
+ else if (__n < __bc) {
+ __n = std::max<size_type>(
+ __n,
+ std::__is_hash_power2(__bc) ? std::__next_hash_pow2(size_t(std::ceil(float(size()) / max_load_factor())))
+ : std::__next_prime(size_t(std::ceil(float(size()) / max_load_factor()))));
+ if (__n < __bc)
+ __do_rehash<_UniqueKeys>(__n);
+ }
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <bool _UniqueKeys>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__do_rehash(size_type __nbc) {
+ __pointer_allocator& __npa = __bucket_list_.get_deleter().__alloc();
+ __bucket_list_.reset(__nbc > 0 ? __pointer_alloc_traits::allocate(__npa, __nbc) : nullptr);
+ __bucket_list_.get_deleter().size() = __nbc;
+ if (__nbc > 0) {
+ for (size_type __i = 0; __i < __nbc; ++__i)
+ __bucket_list_[__i] = nullptr;
+ __next_pointer __pp = __p1_.first().__ptr();
+ __next_pointer __cp = __pp->__next_;
+ if (__cp != nullptr) {
+ size_type __chash = std::__constrain_hash(__cp->__hash(), __nbc);
+ __bucket_list_[__chash] = __pp;
+ size_type __phash = __chash;
+ for (__pp = __cp, void(), __cp = __cp->__next_; __cp != nullptr; __cp = __pp->__next_) {
+ __chash = std::__constrain_hash(__cp->__hash(), __nbc);
+ if (__chash == __phash)
+ __pp = __cp;
+ else {
+ if (__bucket_list_[__chash] == nullptr) {
+ __bucket_list_[__chash] = __pp;
+ __pp = __cp;
+ __phash = __chash;
+ } else {
+ __next_pointer __np = __cp;
+ if _LIBCPP_CONSTEXPR_SINCE_CXX17 (!_UniqueKeys) {
+ for (; __np->__next_ != nullptr &&
+ key_eq()(__cp->__upcast()->__get_value(), __np->__next_->__upcast()->__get_value());
+ __np = __np->__next_)
+ ;
+ }
+ __pp->__next_ = __np->__next_;
+ __np->__next_ = __bucket_list_[__chash]->__next_;
+ __bucket_list_[__chash]->__next_ = __cp;
+ }
+ }
+ }
+ }
+ }
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::find(const _Key& __k) {
+ size_t __hash = hash_function()(__k);
+ size_type __bc = bucket_count();
+ if (__bc != 0) {
+ size_t __chash = std::__constrain_hash(__hash, __bc);
+ __next_pointer __nd = __bucket_list_[__chash];
+ if (__nd != nullptr) {
+ for (__nd = __nd->__next_;
+ __nd != nullptr && (__nd->__hash() == __hash || std::__constrain_hash(__nd->__hash(), __bc) == __chash);
+ __nd = __nd->__next_) {
+ if ((__nd->__hash() == __hash) && key_eq()(__nd->__upcast()->__get_value(), __k))
+ return iterator(__nd);
+ }
+ }
+ }
+ return end();
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::find(const _Key& __k) const {
+ size_t __hash = hash_function()(__k);
+ size_type __bc = bucket_count();
+ if (__bc != 0) {
+ size_t __chash = std::__constrain_hash(__hash, __bc);
+ __next_pointer __nd = __bucket_list_[__chash];
+ if (__nd != nullptr) {
+ for (__nd = __nd->__next_;
+ __nd != nullptr && (__hash == __nd->__hash() || std::__constrain_hash(__nd->__hash(), __bc) == __chash);
+ __nd = __nd->__next_) {
+ if ((__nd->__hash() == __hash) && key_eq()(__nd->__upcast()->__get_value(), __k))
+ return const_iterator(__nd);
+ }
+ }
+ }
+ return end();
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class... _Args>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node(_Args&&... __args) {
+ static_assert(!__is_hash_value_type<_Args...>::value, "Construct cannot be called with a hash value type");
+ __node_allocator& __na = __node_alloc();
+ __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
+
+ // Begin the lifetime of the node itself. Note that this doesn't begin the lifetime of the value
+ // held inside the node, since we need to use the allocator's construct() method for that.
+ //
+ // We don't use the allocator's construct() method to construct the node itself since the
+ // Cpp17FooInsertable named requirements don't require the allocator's construct() method
+ // to work on anything other than the value_type.
+ std::__construct_at(std::addressof(*__h), /* next = */ nullptr, /* hash = */ 0);
+
+ // Now construct the value_type using the allocator's construct() method.
+ __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__get_value()), std::forward<_Args>(__args)...);
+ __h.get_deleter().__value_constructed = true;
+
+ __h->__hash_ = hash_function()(__h->__get_value());
+ return __h;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _First, class... _Rest>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node_hash(size_t __hash, _First&& __f, _Rest&&... __rest) {
+ static_assert(!__is_hash_value_type<_First, _Rest...>::value, "Construct cannot be called with a hash value type");
+ __node_allocator& __na = __node_alloc();
+ __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
+ std::__construct_at(std::addressof(*__h), /* next = */ nullptr, /* hash = */ __hash);
+ __node_traits::construct(
+ __na, _NodeTypes::__get_ptr(__h->__get_value()), std::forward<_First>(__f), std::forward<_Rest>(__rest)...);
+ __h.get_deleter().__value_constructed = true;
+ return __h;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __p) {
+ __next_pointer __np = __p.__node_;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __p != end(), "unordered container::erase(iterator) called with a non-dereferenceable iterator");
+ iterator __r(__np);
+ ++__r;
+ remove(__p);
+ return __r;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __first, const_iterator __last) {
+ for (const_iterator __p = __first; __first != __last; __p = __first) {
+ ++__first;
+ erase(__p);
+ }
+ __next_pointer __np = __last.__node_;
+ return iterator(__np);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__erase_unique(const _Key& __k) {
+ iterator __i = find(__k);
+ if (__i == end())
+ return 0;
+ erase(__i);
+ return 1;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__erase_multi(const _Key& __k) {
+ size_type __r = 0;
+ iterator __i = find(__k);
+ if (__i != end()) {
+ iterator __e = end();
+ do {
+ erase(__i++);
+ ++__r;
+ } while (__i != __e && key_eq()(*__i, __k));
+ }
+ return __r;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::remove(const_iterator __p) _NOEXCEPT {
+ // current node
+ __next_pointer __cn = __p.__node_;
+ size_type __bc = bucket_count();
+ size_t __chash = std::__constrain_hash(__cn->__hash(), __bc);
+ // find previous node
+ __next_pointer __pn = __bucket_list_[__chash];
+ for (; __pn->__next_ != __cn; __pn = __pn->__next_)
+ ;
+ // Fix up __bucket_list_
+ // if __pn is not in same bucket (before begin is not in same bucket) &&
+ // if __cn->__next_ is not in same bucket (nullptr is not in same bucket)
+ if (__pn == __p1_.first().__ptr() || std::__constrain_hash(__pn->__hash(), __bc) != __chash) {
+ if (__cn->__next_ == nullptr || std::__constrain_hash(__cn->__next_->__hash(), __bc) != __chash)
+ __bucket_list_[__chash] = nullptr;
+ }
+ // if __cn->__next_ is not in same bucket (nullptr is in same bucket)
+ if (__cn->__next_ != nullptr) {
+ size_t __nhash = std::__constrain_hash(__cn->__next_->__hash(), __bc);
+ if (__nhash != __chash)
+ __bucket_list_[__nhash] = __pn;
+ }
+ // remove __cn
+ __pn->__next_ = __cn->__next_;
+ __cn->__next_ = nullptr;
+ --size();
+ return __node_holder(__cn->__upcast(), _Dp(__node_alloc(), true));
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+inline typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__count_unique(const _Key& __k) const {
+ return static_cast<size_type>(find(__k) != end());
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__count_multi(const _Key& __k) const {
+ size_type __r = 0;
+ const_iterator __i = find(__k);
+ if (__i != end()) {
+ const_iterator __e = end();
+ do {
+ ++__i;
+ ++__r;
+ } while (__i != __e && key_eq()(*__i, __k));
+ }
+ return __r;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator,
+ typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_unique(const _Key& __k) {
+ iterator __i = find(__k);
+ iterator __j = __i;
+ if (__i != end())
+ ++__j;
+ return pair<iterator, iterator>(__i, __j);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator,
+ typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_unique(const _Key& __k) const {
+ const_iterator __i = find(__k);
+ const_iterator __j = __i;
+ if (__i != end())
+ ++__j;
+ return pair<const_iterator, const_iterator>(__i, __j);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator,
+ typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_multi(const _Key& __k) {
+ iterator __i = find(__k);
+ iterator __j = __i;
+ if (__i != end()) {
+ iterator __e = end();
+ do {
+ ++__j;
+ } while (__j != __e && key_eq()(*__j, __k));
+ }
+ return pair<iterator, iterator>(__i, __j);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+template <class _Key>
+pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator,
+ typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator>
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_multi(const _Key& __k) const {
+ const_iterator __i = find(__k);
+ const_iterator __j = __i;
+ if (__i != end()) {
+ const_iterator __e = end();
+ do {
+ ++__j;
+ } while (__j != __e && key_eq()(*__j, __k));
+ }
+ return pair<const_iterator, const_iterator>(__i, __j);
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+void __hash_table<_Tp, _Hash, _Equal, _Alloc>::swap(__hash_table& __u)
+#if _LIBCPP_STD_VER <= 11
+ _NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal> &&
+ (!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value ||
+ __is_nothrow_swappable_v<__pointer_allocator>) &&
+ (!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>))
+#else
+ _NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal>)
+#endif
+{
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __node_traits::propagate_on_container_swap::value || this->__node_alloc() == __u.__node_alloc(),
+ "unordered container::swap: Either propagate_on_container_swap "
+ "must be true or the allocators must compare equal");
+ {
+ __node_pointer_pointer __npp = __bucket_list_.release();
+ __bucket_list_.reset(__u.__bucket_list_.release());
+ __u.__bucket_list_.reset(__npp);
+ }
+ std::swap(__bucket_list_.get_deleter().size(), __u.__bucket_list_.get_deleter().size());
+ std::__swap_allocator(__bucket_list_.get_deleter().__alloc(), __u.__bucket_list_.get_deleter().__alloc());
+ std::__swap_allocator(__node_alloc(), __u.__node_alloc());
+ std::swap(__p1_.first().__next_, __u.__p1_.first().__next_);
+ __p2_.swap(__u.__p2_);
+ __p3_.swap(__u.__p3_);
+ if (size() > 0)
+ __bucket_list_[std::__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] = __p1_.first().__ptr();
+ if (__u.size() > 0)
+ __u.__bucket_list_[std::__constrain_hash(__u.__p1_.first().__next_->__hash(), __u.bucket_count())] =
+ __u.__p1_.first().__ptr();
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::bucket_size(size_type __n) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n < bucket_count(), "unordered container::bucket_size(n) called with n >= bucket_count()");
+ __next_pointer __np = __bucket_list_[__n];
+ size_type __bc = bucket_count();
+ size_type __r = 0;
+ if (__np != nullptr) {
+ for (__np = __np->__next_; __np != nullptr && std::__constrain_hash(__np->__hash(), __bc) == __n;
+ __np = __np->__next_, (void)++__r)
+ ;
+ }
+ return __r;
+}
+
+template <class _Tp, class _Hash, class _Equal, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(__hash_table<_Tp, _Hash, _Equal, _Alloc>& __x, __hash_table<_Tp, _Hash, _Equal, _Alloc>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___HASH_TABLE
diff --git a/libcxx/include/__cxx03/__ios/fpos.h b/libcxx/include/__cxx03/__ios/fpos.h
new file mode 100644
index 00000000000000..1af1e23ee50da1
--- /dev/null
+++ b/libcxx/include/__cxx03/__ios/fpos.h
@@ -0,0 +1,76 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___IOS_FPOS_H
+#define _LIBCPP___IOS_FPOS_H
+
+#include <__config>
+#include <__fwd/ios.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _StateT>
+class _LIBCPP_TEMPLATE_VIS fpos {
+private:
+ _StateT __st_;
+ streamoff __off_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI fpos(streamoff __off = streamoff()) : __st_(), __off_(__off) {}
+
+ _LIBCPP_HIDE_FROM_ABI operator streamoff() const { return __off_; }
+
+ _LIBCPP_HIDE_FROM_ABI _StateT state() const { return __st_; }
+ _LIBCPP_HIDE_FROM_ABI void state(_StateT __st) { __st_ = __st; }
+
+ _LIBCPP_HIDE_FROM_ABI fpos& operator+=(streamoff __off) {
+ __off_ += __off;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI fpos operator+(streamoff __off) const {
+ fpos __t(*this);
+ __t += __off;
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI fpos& operator-=(streamoff __off) {
+ __off_ -= __off;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI fpos operator-(streamoff __off) const {
+ fpos __t(*this);
+ __t -= __off;
+ return __t;
+ }
+};
+
+template <class _StateT>
+inline _LIBCPP_HIDE_FROM_ABI streamoff operator-(const fpos<_StateT>& __x, const fpos<_StateT>& __y) {
+ return streamoff(__x) - streamoff(__y);
+}
+
+template <class _StateT>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const fpos<_StateT>& __x, const fpos<_StateT>& __y) {
+ return streamoff(__x) == streamoff(__y);
+}
+
+template <class _StateT>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const fpos<_StateT>& __x, const fpos<_StateT>& __y) {
+ return streamoff(__x) != streamoff(__y);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___IOS_FPOS_H
diff --git a/libcxx/include/__cxx03/__iterator/access.h b/libcxx/include/__cxx03/__iterator/access.h
new file mode 100644
index 00000000000000..acc4f60bf697ea
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/access.h
@@ -0,0 +1,95 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ACCESS_H
+#define _LIBCPP___ITERATOR_ACCESS_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, size_t _Np>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp* begin(_Tp (&__array)[_Np]) _NOEXCEPT {
+ return __array;
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp* end(_Tp (&__array)[_Np]) _NOEXCEPT {
+ return __array + _Np;
+}
+
+#if !defined(_LIBCPP_CXX03_LANG)
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto begin(_Cp& __c) -> decltype(__c.begin()) {
+ return __c.begin();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto begin(const _Cp& __c) -> decltype(__c.begin()) {
+ return __c.begin();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto end(_Cp& __c) -> decltype(__c.end()) {
+ return __c.end();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto end(const _Cp& __c) -> decltype(__c.end()) {
+ return __c.end();
+}
+
+# if _LIBCPP_STD_VER >= 14
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+cbegin(const _Cp& __c) noexcept(noexcept(std::begin(__c))) -> decltype(std::begin(__c)) {
+ return std::begin(__c);
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI constexpr auto cend(const _Cp& __c) noexcept(noexcept(std::end(__c))) -> decltype(std::end(__c)) {
+ return std::end(__c);
+}
+
+# endif
+
+#else // defined(_LIBCPP_CXX03_LANG)
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI typename _Cp::iterator begin(_Cp& __c) {
+ return __c.begin();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI typename _Cp::const_iterator begin(const _Cp& __c) {
+ return __c.begin();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI typename _Cp::iterator end(_Cp& __c) {
+ return __c.end();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI typename _Cp::const_iterator end(const _Cp& __c) {
+ return __c.end();
+}
+
+#endif // !defined(_LIBCPP_CXX03_LANG)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_ACCESS_H
diff --git a/libcxx/include/__cxx03/__iterator/advance.h b/libcxx/include/__cxx03/__iterator/advance.h
new file mode 100644
index 00000000000000..296db1aaab6526
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/advance.h
@@ -0,0 +1,205 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ADVANCE_H
+#define _LIBCPP___ITERATOR_ADVANCE_H
+
+#include <__assert>
+#include <__concepts/assignable.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+#include <__utility/convert_to_integral.h>
+#include <__utility/declval.h>
+#include <__utility/move.h>
+#include <__utility/unreachable.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIter>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 void
+__advance(_InputIter& __i, typename iterator_traits<_InputIter>::difference_type __n, input_iterator_tag) {
+ for (; __n > 0; --__n)
+ ++__i;
+}
+
+template <class _BiDirIter>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 void
+__advance(_BiDirIter& __i, typename iterator_traits<_BiDirIter>::difference_type __n, bidirectional_iterator_tag) {
+ if (__n >= 0)
+ for (; __n > 0; --__n)
+ ++__i;
+ else
+ for (; __n < 0; ++__n)
+ --__i;
+}
+
+template <class _RandIter>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 void
+__advance(_RandIter& __i, typename iterator_traits<_RandIter>::difference_type __n, random_access_iterator_tag) {
+ __i += __n;
+}
+
+template < class _InputIter,
+ class _Distance,
+ class _IntegralDistance = decltype(std::__convert_to_integral(std::declval<_Distance>())),
+ __enable_if_t<is_integral<_IntegralDistance>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 void advance(_InputIter& __i, _Distance __orig_n) {
+ typedef typename iterator_traits<_InputIter>::difference_type _Difference;
+ _Difference __n = static_cast<_Difference>(std::__convert_to_integral(__orig_n));
+ // Calling `advance` with a negative value on a non-bidirectional iterator is a no-op in the current implementation.
+ _LIBCPP_ASSERT_PEDANTIC(__n >= 0 || __has_bidirectional_iterator_category<_InputIter>::value,
+ "Attempt to advance(it, n) with negative n on a non-bidirectional iterator");
+ std::__advance(__i, __n, typename iterator_traits<_InputIter>::iterator_category());
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+// [range.iter.op.advance]
+
+namespace ranges {
+namespace __advance {
+
+struct __fn {
+private:
+ template <class _Ip>
+ _LIBCPP_HIDE_FROM_ABI static constexpr void __advance_forward(_Ip& __i, iter_difference_t<_Ip> __n) {
+ while (__n > 0) {
+ --__n;
+ ++__i;
+ }
+ }
+
+ template <class _Ip>
+ _LIBCPP_HIDE_FROM_ABI static constexpr void __advance_backward(_Ip& __i, iter_difference_t<_Ip> __n) {
+ while (__n < 0) {
+ ++__n;
+ --__i;
+ }
+ }
+
+public:
+ // Preconditions: If `I` does not model `bidirectional_iterator`, `n` is not negative.
+ template <input_or_output_iterator _Ip>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_Ip& __i, iter_difference_t<_Ip> __n) const {
+ // Calling `advance` with a negative value on a non-bidirectional iterator is a no-op in the current implementation.
+ _LIBCPP_ASSERT_PEDANTIC(
+ __n >= 0 || bidirectional_iterator<_Ip>, "If `n < 0`, then `bidirectional_iterator<I>` must be true.");
+
+ // If `I` models `random_access_iterator`, equivalent to `i += n`.
+ if constexpr (random_access_iterator<_Ip>) {
+ __i += __n;
+ return;
+ } else if constexpr (bidirectional_iterator<_Ip>) {
+ // Otherwise, if `n` is non-negative, increments `i` by `n`.
+ __advance_forward(__i, __n);
+ // Otherwise, decrements `i` by `-n`.
+ __advance_backward(__i, __n);
+ return;
+ } else {
+ // Otherwise, if `n` is non-negative, increments `i` by `n`.
+ __advance_forward(__i, __n);
+ return;
+ }
+ }
+
+ // Preconditions: Either `assignable_from<I&, S> || sized_sentinel_for<S, I>` is modeled, or [i, bound_sentinel)
+ // denotes a range.
+ template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_Ip& __i, _Sp __bound_sentinel) const {
+ // If `I` and `S` model `assignable_from<I&, S>`, equivalent to `i = std::move(bound_sentinel)`.
+ if constexpr (assignable_from<_Ip&, _Sp>) {
+ __i = std::move(__bound_sentinel);
+ }
+ // Otherwise, if `S` and `I` model `sized_sentinel_for<S, I>`, equivalent to `ranges::advance(i, bound_sentinel -
+ // i)`.
+ else if constexpr (sized_sentinel_for<_Sp, _Ip>) {
+ (*this)(__i, __bound_sentinel - __i);
+ }
+ // Otherwise, while `bool(i != bound_sentinel)` is true, increments `i`.
+ else {
+ while (__i != __bound_sentinel) {
+ ++__i;
+ }
+ }
+ }
+
+ // Preconditions:
+ // * If `n > 0`, [i, bound_sentinel) denotes a range.
+ // * If `n == 0`, [i, bound_sentinel) or [bound_sentinel, i) denotes a range.
+ // * If `n < 0`, [bound_sentinel, i) denotes a range, `I` models `bidirectional_iterator`, and `I` and `S` model
+ // `same_as<I, S>`.
+ // Returns: `n - M`, where `M` is the difference between the ending and starting position.
+ template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp>
+ _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Ip>
+ operator()(_Ip& __i, iter_difference_t<_Ip> __n, _Sp __bound_sentinel) const {
+ // Calling `advance` with a negative value on a non-bidirectional iterator is a no-op in the current implementation.
+ _LIBCPP_ASSERT_PEDANTIC((__n >= 0) || (bidirectional_iterator<_Ip> && same_as<_Ip, _Sp>),
+ "If `n < 0`, then `bidirectional_iterator<I> && same_as<I, S>` must be true.");
+ // If `S` and `I` model `sized_sentinel_for<S, I>`:
+ if constexpr (sized_sentinel_for<_Sp, _Ip>) {
+ // If |n| >= |bound_sentinel - i|, equivalent to `ranges::advance(i, bound_sentinel)`.
+ // __magnitude_geq(a, b) returns |a| >= |b|, assuming they have the same sign.
+ auto __magnitude_geq = [](auto __a, auto __b) { return __a == 0 ? __b == 0 : __a > 0 ? __a >= __b : __a <= __b; };
+ if (const auto __m = __bound_sentinel - __i; __magnitude_geq(__n, __m)) {
+ (*this)(__i, __bound_sentinel);
+ return __n - __m;
+ }
+
+ // Otherwise, equivalent to `ranges::advance(i, n)`.
+ (*this)(__i, __n);
+ return 0;
+ } else {
+ // Otherwise, if `n` is non-negative, while `bool(i != bound_sentinel)` is true, increments `i` but at
+ // most `n` times.
+ while (__n > 0 && __i != __bound_sentinel) {
+ ++__i;
+ --__n;
+ }
+
+ // Otherwise, while `bool(i != bound_sentinel)` is true, decrements `i` but at most `-n` times.
+ if constexpr (bidirectional_iterator<_Ip> && same_as<_Ip, _Sp>) {
+ while (__n < 0 && __i != __bound_sentinel) {
+ --__i;
+ ++__n;
+ }
+ }
+ return __n;
+ }
+
+ __libcpp_unreachable();
+ }
+};
+
+} // namespace __advance
+
+inline namespace __cpo {
+inline constexpr auto advance = __advance::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_ADVANCE_H
diff --git a/libcxx/include/__cxx03/__iterator/aliasing_iterator.h b/libcxx/include/__cxx03/__iterator/aliasing_iterator.h
new file mode 100644
index 00000000000000..94ba577078b5e8
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/aliasing_iterator.h
@@ -0,0 +1,127 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ALIASING_ITERATOR_H
+#define _LIBCPP___ITERATOR_ALIASING_ITERATOR_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/is_trivial.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// This iterator wrapper is used to type-pun an iterator to return a different type. This is done without UB by not
+// actually punning the type, but instead inspecting the object representation of the base type and copying that into
+// an instance of the alias type. For that reason the alias type has to be trivial. The alias is returned as a prvalue
+// when derferencing the iterator, since it is temporary storage. This wrapper is used to vectorize some algorithms.
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _BaseIter, class _Alias>
+struct __aliasing_iterator_wrapper {
+ class __iterator {
+ _BaseIter __base_ = nullptr;
+
+ using __iter_traits = iterator_traits<_BaseIter>;
+ using __base_value_type = typename __iter_traits::value_type;
+
+ static_assert(__has_random_access_iterator_category<_BaseIter>::value,
+ "The base iterator has to be a random access iterator!");
+
+ public:
+ using iterator_category = random_access_iterator_tag;
+ using value_type = _Alias;
+ using difference_type = ptrdiff_t;
+ using reference = value_type&;
+ using pointer = value_type*;
+
+ static_assert(is_trivial<value_type>::value);
+ static_assert(sizeof(__base_value_type) == sizeof(value_type));
+
+ _LIBCPP_HIDE_FROM_ABI __iterator() = default;
+ _LIBCPP_HIDE_FROM_ABI __iterator(_BaseIter __base) _NOEXCEPT : __base_(__base) {}
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator++() _NOEXCEPT {
+ ++__base_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator operator++(int) _NOEXCEPT {
+ __iterator __tmp(*this);
+ ++__base_;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator--() _NOEXCEPT {
+ --__base_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator operator--(int) _NOEXCEPT {
+ __iterator __tmp(*this);
+ --__base_;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend __iterator operator+(__iterator __iter, difference_type __n) _NOEXCEPT {
+ return __iterator(__iter.__base_ + __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend __iterator operator+(difference_type __n, __iterator __iter) _NOEXCEPT {
+ return __iterator(__n + __iter.__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator+=(difference_type __n) _NOEXCEPT {
+ __base_ += __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend __iterator operator-(__iterator __iter, difference_type __n) _NOEXCEPT {
+ return __iterator(__iter.__base_ - __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend difference_type operator-(__iterator __lhs, __iterator __rhs) _NOEXCEPT {
+ return __lhs.__base_ - __rhs.__base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator-=(difference_type __n) _NOEXCEPT {
+ __base_ -= __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _BaseIter __base() const _NOEXCEPT { return __base_; }
+
+ _LIBCPP_HIDE_FROM_ABI _Alias operator*() const _NOEXCEPT {
+ _Alias __val;
+ __builtin_memcpy(&__val, std::__to_address(__base_), sizeof(value_type));
+ return __val;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI value_type operator[](difference_type __n) const _NOEXCEPT { return *(*this + __n); }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const __iterator& __lhs, const __iterator& __rhs) _NOEXCEPT {
+ return __lhs.__base_ == __rhs.__base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator!=(const __iterator& __lhs, const __iterator& __rhs) _NOEXCEPT {
+ return __lhs.__base_ != __rhs.__base_;
+ }
+ };
+};
+
+// This is required to avoid ADL instantiations on _BaseT
+template <class _BaseT, class _Alias>
+using __aliasing_iterator = typename __aliasing_iterator_wrapper<_BaseT, _Alias>::__iterator;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_ALIASING_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/back_insert_iterator.h b/libcxx/include/__cxx03/__iterator/back_insert_iterator.h
new file mode 100644
index 00000000000000..6d3dd4b12966fe
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/back_insert_iterator.h
@@ -0,0 +1,85 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_BACK_INSERT_ITERATOR_H
+#define _LIBCPP___ITERATOR_BACK_INSERT_ITERATOR_H
+
+#include <__config>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Container>
+class _LIBCPP_TEMPLATE_VIS back_insert_iterator
+#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<output_iterator_tag, void, void, void, void>
+#endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ _Container* container;
+
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+#if _LIBCPP_STD_VER >= 20
+ typedef ptrdiff_t difference_type;
+#else
+ typedef void difference_type;
+#endif
+ typedef void pointer;
+ typedef void reference;
+ typedef _Container container_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit back_insert_iterator(_Container& __x)
+ : container(std::addressof(__x)) {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator&
+ operator=(const typename _Container::value_type& __value) {
+ container->push_back(__value);
+ return *this;
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator&
+ operator=(typename _Container::value_type&& __value) {
+ container->push_back(std::move(__value));
+ return *this;
+ }
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator& operator*() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator& operator++() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator operator++(int) { return *this; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Container* __get_container() const { return container; }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(back_insert_iterator);
+
+template <class _Container>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 back_insert_iterator<_Container>
+back_inserter(_Container& __x) {
+ return back_insert_iterator<_Container>(__x);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_BACK_INSERT_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/bounded_iter.h b/libcxx/include/__cxx03/__iterator/bounded_iter.h
new file mode 100644
index 00000000000000..8a81c9ffbfc3fc
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/bounded_iter.h
@@ -0,0 +1,283 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_BOUNDED_ITER_H
+#define _LIBCPP___ITERATOR_BOUNDED_ITER_H
+
+#include <__assert>
+#include <__compare/ordering.h>
+#include <__compare/three_way_comparable.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_convertible.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Iterator wrapper that carries the valid range it is allowed to access.
+//
+// This is a simple iterator wrapper for contiguous iterators that points
+// within a [begin, end] range and carries these bounds with it. The iterator
+// ensures that it is pointing within [begin, end) range when it is
+// dereferenced. It also ensures that it is never iterated outside of
+// [begin, end]. This is important for two reasons:
+//
+// 1. It allows `operator*` and `operator++` bounds checks to be `iter != end`.
+// This is both less for the optimizer to prove, and aligns with how callers
+// typically use iterators.
+//
+// 2. Advancing an iterator out of bounds is undefined behavior (see the table
+// in [input.iterators]). In particular, when the underlying iterator is a
+// pointer, it is undefined at the language level (see [expr.add]). If
+// bounded iterators exhibited this undefined behavior, we risk compiler
+// optimizations deleting non-redundant bounds checks.
+template <class _Iterator, class = __enable_if_t< __libcpp_is_contiguous_iterator<_Iterator>::value > >
+struct __bounded_iter {
+ using value_type = typename iterator_traits<_Iterator>::value_type;
+ using difference_type = typename iterator_traits<_Iterator>::difference_type;
+ using pointer = typename iterator_traits<_Iterator>::pointer;
+ using reference = typename iterator_traits<_Iterator>::reference;
+ using iterator_category = typename iterator_traits<_Iterator>::iterator_category;
+#if _LIBCPP_STD_VER >= 20
+ using iterator_concept = contiguous_iterator_tag;
+#endif
+
+ // Create a singular iterator.
+ //
+ // Such an iterator points past the end of an empty span, so it is not dereferenceable.
+ // Observing operations like comparison and assignment are valid.
+ _LIBCPP_HIDE_FROM_ABI __bounded_iter() = default;
+
+ _LIBCPP_HIDE_FROM_ABI __bounded_iter(__bounded_iter const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __bounded_iter(__bounded_iter&&) = default;
+
+ template <class _OtherIterator, __enable_if_t< is_convertible<_OtherIterator, _Iterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __bounded_iter(__bounded_iter<_OtherIterator> const& __other) _NOEXCEPT
+ : __current_(__other.__current_),
+ __begin_(__other.__begin_),
+ __end_(__other.__end_) {}
+
+ // Assign a bounded iterator to another one, rebinding the bounds of the iterator as well.
+ _LIBCPP_HIDE_FROM_ABI __bounded_iter& operator=(__bounded_iter const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __bounded_iter& operator=(__bounded_iter&&) = default;
+
+private:
+ // Create an iterator wrapping the given iterator, and whose bounds are described
+ // by the provided [begin, end] range.
+ //
+ // The constructor does not check whether the resulting iterator is within its bounds. It is a
+ // responsibility of the container to ensure that the given bounds are valid.
+ //
+ // Since it is non-standard for iterators to have this constructor, __bounded_iter must
+ // be created via `std::__make_bounded_iter`.
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __bounded_iter(_Iterator __current, _Iterator __begin, _Iterator __end)
+ : __current_(__current), __begin_(__begin), __end_(__end) {
+ _LIBCPP_ASSERT_INTERNAL(
+ __begin <= __current, "__bounded_iter(current, begin, end): current and begin are inconsistent");
+ _LIBCPP_ASSERT_INTERNAL(
+ __current <= __end, "__bounded_iter(current, begin, end): current and end are inconsistent");
+ }
+
+ template <class _It>
+ friend _LIBCPP_CONSTEXPR __bounded_iter<_It> __make_bounded_iter(_It, _It, _It);
+
+public:
+ // Dereference and indexing operations.
+ //
+ // These operations check that the iterator is dereferenceable. Since the class invariant is
+ // that the iterator is always within `[begin, end]`, we only need to check it's not pointing to
+ // `end`. This is easier for the optimizer because it aligns with the `iter != container.end()`
+ // checks that typical callers already use (see
+ // https://github.com/llvm/llvm-project/issues/78829).
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator*() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __current_ != __end_, "__bounded_iter::operator*: Attempt to dereference an iterator at the end");
+ return *__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pointer operator->() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __current_ != __end_, "__bounded_iter::operator->: Attempt to dereference an iterator at the end");
+ return std::__to_address(__current_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator[](difference_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n >= __begin_ - __current_, "__bounded_iter::operator[]: Attempt to index an iterator past the start");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n < __end_ - __current_, "__bounded_iter::operator[]: Attempt to index an iterator at or past the end");
+ return __current_[__n];
+ }
+
+ // Arithmetic operations.
+ //
+ // These operations check that the iterator remains within `[begin, end]`.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __bounded_iter& operator++() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __current_ != __end_, "__bounded_iter::operator++: Attempt to advance an iterator past the end");
+ ++__current_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __bounded_iter operator++(int) _NOEXCEPT {
+ __bounded_iter __tmp(*this);
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __bounded_iter& operator--() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __current_ != __begin_, "__bounded_iter::operator--: Attempt to rewind an iterator past the start");
+ --__current_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __bounded_iter operator--(int) _NOEXCEPT {
+ __bounded_iter __tmp(*this);
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __bounded_iter& operator+=(difference_type __n) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n >= __begin_ - __current_, "__bounded_iter::operator+=: Attempt to rewind an iterator past the start");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n <= __end_ - __current_, "__bounded_iter::operator+=: Attempt to advance an iterator past the end");
+ __current_ += __n;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 friend __bounded_iter
+ operator+(__bounded_iter const& __self, difference_type __n) _NOEXCEPT {
+ __bounded_iter __tmp(__self);
+ __tmp += __n;
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 friend __bounded_iter
+ operator+(difference_type __n, __bounded_iter const& __self) _NOEXCEPT {
+ __bounded_iter __tmp(__self);
+ __tmp += __n;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __bounded_iter& operator-=(difference_type __n) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n <= __current_ - __begin_, "__bounded_iter::operator-=: Attempt to rewind an iterator past the start");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __n >= __current_ - __end_, "__bounded_iter::operator-=: Attempt to advance an iterator past the end");
+ __current_ -= __n;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 friend __bounded_iter
+ operator-(__bounded_iter const& __self, difference_type __n) _NOEXCEPT {
+ __bounded_iter __tmp(__self);
+ __tmp -= __n;
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 friend difference_type
+ operator-(__bounded_iter const& __x, __bounded_iter const& __y) _NOEXCEPT {
+ return __x.__current_ - __y.__current_;
+ }
+
+ // Comparison operations.
+ //
+ // These operations do not check whether the iterators are within their bounds.
+ // The valid range for each iterator is also not considered as part of the comparison,
+ // i.e. two iterators pointing to the same location will be considered equal even
+ // if they have different validity ranges.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR friend bool
+ operator==(__bounded_iter const& __x, __bounded_iter const& __y) _NOEXCEPT {
+ return __x.__current_ == __y.__current_;
+ }
+
+#if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR friend bool
+ operator!=(__bounded_iter const& __x, __bounded_iter const& __y) _NOEXCEPT {
+ return __x.__current_ != __y.__current_;
+ }
+#endif
+
+ // TODO(mordante) disable these overloads in the LLVM 20 release.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR friend bool
+ operator<(__bounded_iter const& __x, __bounded_iter const& __y) _NOEXCEPT {
+ return __x.__current_ < __y.__current_;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR friend bool
+ operator>(__bounded_iter const& __x, __bounded_iter const& __y) _NOEXCEPT {
+ return __x.__current_ > __y.__current_;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR friend bool
+ operator<=(__bounded_iter const& __x, __bounded_iter const& __y) _NOEXCEPT {
+ return __x.__current_ <= __y.__current_;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR friend bool
+ operator>=(__bounded_iter const& __x, __bounded_iter const& __y) _NOEXCEPT {
+ return __x.__current_ >= __y.__current_;
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr friend strong_ordering
+ operator<=>(__bounded_iter const& __x, __bounded_iter const& __y) noexcept {
+ if constexpr (three_way_comparable<_Iterator, strong_ordering>) {
+ return __x.__current_ <=> __y.__current_;
+ } else {
+ if (__x.__current_ < __y.__current_)
+ return strong_ordering::less;
+
+ if (__x.__current_ == __y.__current_)
+ return strong_ordering::equal;
+
+ return strong_ordering::greater;
+ }
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+private:
+ template <class>
+ friend struct pointer_traits;
+ template <class, class>
+ friend struct __bounded_iter;
+ _Iterator __current_; // current iterator
+ _Iterator __begin_, __end_; // valid range represented as [begin, end]
+};
+
+template <class _It>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __bounded_iter<_It> __make_bounded_iter(_It __it, _It __begin, _It __end) {
+ return __bounded_iter<_It>(std::move(__it), std::move(__begin), std::move(__end));
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _Iterator>
+struct __libcpp_is_contiguous_iterator<__bounded_iter<_Iterator> > : true_type {};
+#endif
+
+template <class _Iterator>
+struct pointer_traits<__bounded_iter<_Iterator> > {
+ using pointer = __bounded_iter<_Iterator>;
+ using element_type = typename pointer_traits<_Iterator>::element_type;
+ using difference_type = typename pointer_traits<_Iterator>::difference_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR static element_type* to_address(pointer __it) _NOEXCEPT {
+ return std::__to_address(__it.__current_);
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_BOUNDED_ITER_H
diff --git a/libcxx/include/__cxx03/__iterator/common_iterator.h b/libcxx/include/__cxx03/__iterator/common_iterator.h
new file mode 100644
index 00000000000000..199de2cc7337b0
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/common_iterator.h
@@ -0,0 +1,299 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_COMMON_ITERATOR_H
+#define _LIBCPP___ITERATOR_COMMON_ITERATOR_H
+
+#include <__assert>
+#include <__concepts/assignable.h>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/copyable.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/equality_comparable.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__memory/addressof.h>
+#include <__type_traits/is_pointer.h>
+#include <__utility/declval.h>
+#include <variant>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Iter>
+concept __can_use_postfix_proxy =
+ constructible_from<iter_value_t<_Iter>, iter_reference_t<_Iter>> && move_constructible<iter_value_t<_Iter>>;
+
+template <input_or_output_iterator _Iter, sentinel_for<_Iter> _Sent>
+ requires(!same_as<_Iter, _Sent> && copyable<_Iter>)
+class common_iterator {
+ struct __proxy {
+ _LIBCPP_HIDE_FROM_ABI constexpr const iter_value_t<_Iter>* operator->() const noexcept {
+ return std::addressof(__value_);
+ }
+ iter_value_t<_Iter> __value_;
+ };
+
+ struct __postfix_proxy {
+ _LIBCPP_HIDE_FROM_ABI constexpr const iter_value_t<_Iter>& operator*() const noexcept { return __value_; }
+ iter_value_t<_Iter> __value_;
+ };
+
+ variant<_Iter, _Sent> __hold_;
+ template <input_or_output_iterator _OtherIter, sentinel_for<_OtherIter> _OtherSent>
+ requires(!same_as<_OtherIter, _OtherSent> && copyable<_OtherIter>)
+ friend class common_iterator;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI common_iterator()
+ requires default_initializable<_Iter>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr common_iterator(_Iter __i) : __hold_(in_place_type<_Iter>, std::move(__i)) {}
+ _LIBCPP_HIDE_FROM_ABI constexpr common_iterator(_Sent __s) : __hold_(in_place_type<_Sent>, std::move(__s)) {}
+
+ template <class _I2, class _S2>
+ requires convertible_to<const _I2&, _Iter> && convertible_to<const _S2&, _Sent>
+ _LIBCPP_HIDE_FROM_ABI constexpr common_iterator(const common_iterator<_I2, _S2>& __other)
+ : __hold_([&]() -> variant<_Iter, _Sent> {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !__other.__hold_.valueless_by_exception(), "Attempted to construct from a valueless common_iterator");
+ if (__other.__hold_.index() == 0)
+ return variant<_Iter, _Sent>{in_place_index<0>, std::__unchecked_get<0>(__other.__hold_)};
+ return variant<_Iter, _Sent>{in_place_index<1>, std::__unchecked_get<1>(__other.__hold_)};
+ }()) {}
+
+ template <class _I2, class _S2>
+ requires convertible_to<const _I2&, _Iter> && convertible_to<const _S2&, _Sent> &&
+ assignable_from<_Iter&, const _I2&> && assignable_from<_Sent&, const _S2&>
+ _LIBCPP_HIDE_FROM_ABI common_iterator& operator=(const common_iterator<_I2, _S2>& __other) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !__other.__hold_.valueless_by_exception(), "Attempted to assign from a valueless common_iterator");
+
+ auto __idx = __hold_.index();
+ auto __other_idx = __other.__hold_.index();
+
+ // If they're the same index, just assign.
+ if (__idx == 0 && __other_idx == 0)
+ std::__unchecked_get<0>(__hold_) = std::__unchecked_get<0>(__other.__hold_);
+ else if (__idx == 1 && __other_idx == 1)
+ std::__unchecked_get<1>(__hold_) = std::__unchecked_get<1>(__other.__hold_);
+
+ // Otherwise replace with the oposite element.
+ else if (__other_idx == 1)
+ __hold_.template emplace<1>(std::__unchecked_get<1>(__other.__hold_));
+ else if (__other_idx == 0)
+ __hold_.template emplace<0>(std::__unchecked_get<0>(__other.__hold_));
+
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ std::holds_alternative<_Iter>(__hold_), "Attempted to dereference a non-dereferenceable common_iterator");
+ return *std::__unchecked_get<_Iter>(__hold_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const
+ requires __dereferenceable<const _Iter>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ std::holds_alternative<_Iter>(__hold_), "Attempted to dereference a non-dereferenceable common_iterator");
+ return *std::__unchecked_get<_Iter>(__hold_);
+ }
+
+ template <class _I2 = _Iter>
+ _LIBCPP_HIDE_FROM_ABI auto operator->() const
+ requires indirectly_readable<const _I2> && (requires(const _I2& __i) {
+ __i.operator->();
+ } || is_reference_v<iter_reference_t<_I2>> || constructible_from<iter_value_t<_I2>, iter_reference_t<_I2>>)
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ std::holds_alternative<_Iter>(__hold_), "Attempted to dereference a non-dereferenceable common_iterator");
+ if constexpr (is_pointer_v<_Iter> || requires(const _Iter& __i) { __i.operator->(); }) {
+ return std::__unchecked_get<_Iter>(__hold_);
+ } else if constexpr (is_reference_v<iter_reference_t<_Iter>>) {
+ auto&& __tmp = *std::__unchecked_get<_Iter>(__hold_);
+ return std::addressof(__tmp);
+ } else {
+ return __proxy{*std::__unchecked_get<_Iter>(__hold_)};
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI common_iterator& operator++() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ std::holds_alternative<_Iter>(__hold_), "Attempted to increment a non-dereferenceable common_iterator");
+ ++std::__unchecked_get<_Iter>(__hold_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI decltype(auto) operator++(int) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ std::holds_alternative<_Iter>(__hold_), "Attempted to increment a non-dereferenceable common_iterator");
+ if constexpr (forward_iterator<_Iter>) {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ } else if constexpr (requires(_Iter& __i) {
+ { *__i++ } -> __can_reference;
+ } || !__can_use_postfix_proxy<_Iter>) {
+ return std::__unchecked_get<_Iter>(__hold_)++;
+ } else {
+ auto __p = __postfix_proxy{**this};
+ ++*this;
+ return __p;
+ }
+ }
+
+ template <class _I2, sentinel_for<_Iter> _S2>
+ requires sentinel_for<_Sent, _I2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool
+ operator==(const common_iterator& __x, const common_iterator<_I2, _S2>& __y) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !__x.__hold_.valueless_by_exception(), "Attempted to compare a valueless common_iterator");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !__y.__hold_.valueless_by_exception(), "Attempted to compare a valueless common_iterator");
+
+ auto __x_index = __x.__hold_.index();
+ auto __y_index = __y.__hold_.index();
+
+ if (__x_index == __y_index)
+ return true;
+
+ if (__x_index == 0)
+ return std::__unchecked_get<_Iter>(__x.__hold_) == std::__unchecked_get<_S2>(__y.__hold_);
+
+ return std::__unchecked_get<_Sent>(__x.__hold_) == std::__unchecked_get<_I2>(__y.__hold_);
+ }
+
+ template <class _I2, sentinel_for<_Iter> _S2>
+ requires sentinel_for<_Sent, _I2> && equality_comparable_with<_Iter, _I2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool
+ operator==(const common_iterator& __x, const common_iterator<_I2, _S2>& __y) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !__x.__hold_.valueless_by_exception(), "Attempted to compare a valueless common_iterator");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !__y.__hold_.valueless_by_exception(), "Attempted to compare a valueless common_iterator");
+
+ auto __x_index = __x.__hold_.index();
+ auto __y_index = __y.__hold_.index();
+
+ if (__x_index == 1 && __y_index == 1)
+ return true;
+
+ if (__x_index == 0 && __y_index == 0)
+ return std::__unchecked_get<_Iter>(__x.__hold_) == std::__unchecked_get<_I2>(__y.__hold_);
+
+ if (__x_index == 0)
+ return std::__unchecked_get<_Iter>(__x.__hold_) == std::__unchecked_get<_S2>(__y.__hold_);
+
+ return std::__unchecked_get<_Sent>(__x.__hold_) == std::__unchecked_get<_I2>(__y.__hold_);
+ }
+
+ template <sized_sentinel_for<_Iter> _I2, sized_sentinel_for<_Iter> _S2>
+ requires sized_sentinel_for<_Sent, _I2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_I2>
+ operator-(const common_iterator& __x, const common_iterator<_I2, _S2>& __y) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !__x.__hold_.valueless_by_exception(), "Attempted to subtract from a valueless common_iterator");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !__y.__hold_.valueless_by_exception(), "Attempted to subtract a valueless common_iterator");
+
+ auto __x_index = __x.__hold_.index();
+ auto __y_index = __y.__hold_.index();
+
+ if (__x_index == 1 && __y_index == 1)
+ return 0;
+
+ if (__x_index == 0 && __y_index == 0)
+ return std::__unchecked_get<_Iter>(__x.__hold_) - std::__unchecked_get<_I2>(__y.__hold_);
+
+ if (__x_index == 0)
+ return std::__unchecked_get<_Iter>(__x.__hold_) - std::__unchecked_get<_S2>(__y.__hold_);
+
+ return std::__unchecked_get<_Sent>(__x.__hold_) - std::__unchecked_get<_I2>(__y.__hold_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_rvalue_reference_t<_Iter>
+ iter_move(const common_iterator& __i) noexcept(noexcept(ranges::iter_move(std::declval<const _Iter&>())))
+ requires input_iterator<_Iter>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ std::holds_alternative<_Iter>(__i.__hold_), "Attempted to iter_move a non-dereferenceable common_iterator");
+ return ranges::iter_move(std::__unchecked_get<_Iter>(__i.__hold_));
+ }
+
+ template <indirectly_swappable<_Iter> _I2, class _S2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void
+ iter_swap(const common_iterator& __x, const common_iterator<_I2, _S2>& __y) noexcept(
+ noexcept(ranges::iter_swap(std::declval<const _Iter&>(), std::declval<const _I2&>()))) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ std::holds_alternative<_Iter>(__x.__hold_), "Attempted to iter_swap a non-dereferenceable common_iterator");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ std::holds_alternative<_I2>(__y.__hold_), "Attempted to iter_swap a non-dereferenceable common_iterator");
+ return ranges::iter_swap(std::__unchecked_get<_Iter>(__x.__hold_), std::__unchecked_get<_I2>(__y.__hold_));
+ }
+};
+
+template <class _Iter, class _Sent>
+struct incrementable_traits<common_iterator<_Iter, _Sent>> {
+ using difference_type = iter_difference_t<_Iter>;
+};
+
+template <class _Iter>
+concept __denotes_forward_iter = requires {
+ typename iterator_traits<_Iter>::iterator_category;
+} && derived_from<typename iterator_traits<_Iter>::iterator_category, forward_iterator_tag>;
+
+template <class _Iter, class _Sent>
+concept __common_iter_has_ptr_op = requires(const common_iterator<_Iter, _Sent>& __a) { __a.operator->(); };
+
+template <class, class>
+struct __arrow_type_or_void {
+ using type = void;
+};
+
+template <class _Iter, class _Sent>
+ requires __common_iter_has_ptr_op<_Iter, _Sent>
+struct __arrow_type_or_void<_Iter, _Sent> {
+ using type = decltype(std::declval<const common_iterator<_Iter, _Sent>&>().operator->());
+};
+
+template <input_iterator _Iter, class _Sent>
+struct iterator_traits<common_iterator<_Iter, _Sent>> {
+ using iterator_concept = _If<forward_iterator<_Iter>, forward_iterator_tag, input_iterator_tag>;
+ using iterator_category = _If<__denotes_forward_iter<_Iter>, forward_iterator_tag, input_iterator_tag>;
+ using pointer = typename __arrow_type_or_void<_Iter, _Sent>::type;
+ using value_type = iter_value_t<_Iter>;
+ using difference_type = iter_difference_t<_Iter>;
+ using reference = iter_reference_t<_Iter>;
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_COMMON_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/concepts.h b/libcxx/include/__cxx03/__iterator/concepts.h
new file mode 100644
index 00000000000000..0a4878308d55f0
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/concepts.h
@@ -0,0 +1,257 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_CONCEPTS_H
+#define _LIBCPP___ITERATOR_CONCEPTS_H
+
+#include <__concepts/arithmetic.h>
+#include <__concepts/assignable.h>
+#include <__concepts/common_reference_with.h>
+#include <__concepts/constructible.h>
+#include <__concepts/copyable.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/equality_comparable.h>
+#include <__concepts/invocable.h>
+#include <__concepts/movable.h>
+#include <__concepts/predicate.h>
+#include <__concepts/regular.h>
+#include <__concepts/relation.h>
+#include <__concepts/same_as.h>
+#include <__concepts/semiregular.h>
+#include <__concepts/totally_ordered.h>
+#include <__config>
+#include <__functional/invoke.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/common_reference.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [iterator.concept.readable]
+template <class _In>
+concept __indirectly_readable_impl =
+ requires(const _In __i) {
+ typename iter_value_t<_In>;
+ typename iter_reference_t<_In>;
+ typename iter_rvalue_reference_t<_In>;
+ { *__i } -> same_as<iter_reference_t<_In>>;
+ { ranges::iter_move(__i) } -> same_as<iter_rvalue_reference_t<_In>>;
+ } && common_reference_with<iter_reference_t<_In>&&, iter_value_t<_In>&> &&
+ common_reference_with<iter_reference_t<_In>&&, iter_rvalue_reference_t<_In>&&> &&
+ common_reference_with<iter_rvalue_reference_t<_In>&&, const iter_value_t<_In>&>;
+
+template <class _In>
+concept indirectly_readable = __indirectly_readable_impl<remove_cvref_t<_In>>;
+
+template <indirectly_readable _Tp>
+using iter_common_reference_t = common_reference_t<iter_reference_t<_Tp>, iter_value_t<_Tp>&>;
+
+// [iterator.concept.writable]
+template <class _Out, class _Tp>
+concept indirectly_writable = requires(_Out&& __o, _Tp&& __t) {
+ *__o = std::forward<_Tp>(__t); // not required to be equality-preserving
+ *std::forward<_Out>(__o) = std::forward<_Tp>(__t); // not required to be equality-preserving
+ const_cast<const iter_reference_t<_Out>&&>(*__o) = std::forward<_Tp>(__t); // not required to be equality-preserving
+ const_cast<const iter_reference_t<_Out>&&>(*std::forward<_Out>(__o)) =
+ std::forward<_Tp>(__t); // not required to be equality-preserving
+};
+
+// [iterator.concept.winc]
+template <class _Tp>
+concept __integer_like = integral<_Tp> && !same_as<_Tp, bool>;
+
+template <class _Tp>
+concept __signed_integer_like = signed_integral<_Tp>;
+
+template <class _Ip>
+concept weakly_incrementable =
+ // TODO: remove this once the clang bug is fixed (bugs.llvm.org/PR48173).
+ !same_as<_Ip, bool> && // Currently, clang does not handle bool correctly.
+ movable<_Ip> && requires(_Ip __i) {
+ typename iter_difference_t<_Ip>;
+ requires __signed_integer_like<iter_difference_t<_Ip>>;
+ { ++__i } -> same_as<_Ip&>; // not required to be equality-preserving
+ __i++; // not required to be equality-preserving
+ };
+
+// [iterator.concept.inc]
+template <class _Ip>
+concept incrementable = regular<_Ip> && weakly_incrementable<_Ip> && requires(_Ip __i) {
+ { __i++ } -> same_as<_Ip>;
+};
+
+// [iterator.concept.iterator]
+template <class _Ip>
+concept input_or_output_iterator = requires(_Ip __i) {
+ { *__i } -> __can_reference;
+} && weakly_incrementable<_Ip>;
+
+// [iterator.concept.sentinel]
+template <class _Sp, class _Ip>
+concept sentinel_for = semiregular<_Sp> && input_or_output_iterator<_Ip> && __weakly_equality_comparable_with<_Sp, _Ip>;
+
+template <class, class>
+inline constexpr bool disable_sized_sentinel_for = false;
+
+template <class _Sp, class _Ip>
+concept sized_sentinel_for =
+ sentinel_for<_Sp, _Ip> && !disable_sized_sentinel_for<remove_cv_t<_Sp>, remove_cv_t<_Ip>> &&
+ requires(const _Ip& __i, const _Sp& __s) {
+ { __s - __i } -> same_as<iter_difference_t<_Ip>>;
+ { __i - __s } -> same_as<iter_difference_t<_Ip>>;
+ };
+
+// [iterator.concept.input]
+template <class _Ip>
+concept input_iterator = input_or_output_iterator<_Ip> && indirectly_readable<_Ip> && requires {
+ typename _ITER_CONCEPT<_Ip>;
+} && derived_from<_ITER_CONCEPT<_Ip>, input_iterator_tag>;
+
+// [iterator.concept.output]
+template <class _Ip, class _Tp>
+concept output_iterator =
+ input_or_output_iterator<_Ip> && indirectly_writable<_Ip, _Tp> && requires(_Ip __it, _Tp&& __t) {
+ *__it++ = std::forward<_Tp>(__t); // not required to be equality-preserving
+ };
+
+// [iterator.concept.forward]
+template <class _Ip>
+concept forward_iterator =
+ input_iterator<_Ip> && derived_from<_ITER_CONCEPT<_Ip>, forward_iterator_tag> && incrementable<_Ip> &&
+ sentinel_for<_Ip, _Ip>;
+
+// [iterator.concept.bidir]
+template <class _Ip>
+concept bidirectional_iterator =
+ forward_iterator<_Ip> && derived_from<_ITER_CONCEPT<_Ip>, bidirectional_iterator_tag> && requires(_Ip __i) {
+ { --__i } -> same_as<_Ip&>;
+ { __i-- } -> same_as<_Ip>;
+ };
+
+template <class _Ip>
+concept random_access_iterator =
+ bidirectional_iterator<_Ip> && derived_from<_ITER_CONCEPT<_Ip>, random_access_iterator_tag> &&
+ totally_ordered<_Ip> && sized_sentinel_for<_Ip, _Ip> &&
+ requires(_Ip __i, const _Ip __j, const iter_difference_t<_Ip> __n) {
+ { __i += __n } -> same_as<_Ip&>;
+ { __j + __n } -> same_as<_Ip>;
+ { __n + __j } -> same_as<_Ip>;
+ { __i -= __n } -> same_as<_Ip&>;
+ { __j - __n } -> same_as<_Ip>;
+ { __j[__n] } -> same_as<iter_reference_t<_Ip>>;
+ };
+
+template <class _Ip>
+concept contiguous_iterator =
+ random_access_iterator<_Ip> && derived_from<_ITER_CONCEPT<_Ip>, contiguous_iterator_tag> &&
+ is_lvalue_reference_v<iter_reference_t<_Ip>> && same_as<iter_value_t<_Ip>, remove_cvref_t<iter_reference_t<_Ip>>> &&
+ requires(const _Ip& __i) {
+ { std::to_address(__i) } -> same_as<add_pointer_t<iter_reference_t<_Ip>>>;
+ };
+
+template <class _Ip>
+concept __has_arrow = input_iterator<_Ip> && (is_pointer_v<_Ip> || requires(_Ip __i) { __i.operator->(); });
+
+// [indirectcallable.indirectinvocable]
+template <class _Fp, class _It>
+concept indirectly_unary_invocable =
+ indirectly_readable<_It> && copy_constructible<_Fp> && invocable<_Fp&, iter_value_t<_It>&> &&
+ invocable<_Fp&, iter_reference_t<_It>> &&
+ common_reference_with< invoke_result_t<_Fp&, iter_value_t<_It>&>, invoke_result_t<_Fp&, iter_reference_t<_It>>>;
+
+template <class _Fp, class _It>
+concept indirectly_regular_unary_invocable =
+ indirectly_readable<_It> && copy_constructible<_Fp> && regular_invocable<_Fp&, iter_value_t<_It>&> &&
+ regular_invocable<_Fp&, iter_reference_t<_It>> &&
+ common_reference_with< invoke_result_t<_Fp&, iter_value_t<_It>&>, invoke_result_t<_Fp&, iter_reference_t<_It>>>;
+
+template <class _Fp, class _It>
+concept indirect_unary_predicate =
+ indirectly_readable<_It> && copy_constructible<_Fp> && predicate<_Fp&, iter_value_t<_It>&> &&
+ predicate<_Fp&, iter_reference_t<_It>>;
+
+template <class _Fp, class _It1, class _It2>
+concept indirect_binary_predicate =
+ indirectly_readable<_It1> && indirectly_readable<_It2> && copy_constructible<_Fp> &&
+ predicate<_Fp&, iter_value_t<_It1>&, iter_value_t<_It2>&> &&
+ predicate<_Fp&, iter_value_t<_It1>&, iter_reference_t<_It2>> &&
+ predicate<_Fp&, iter_reference_t<_It1>, iter_value_t<_It2>&> &&
+ predicate<_Fp&, iter_reference_t<_It1>, iter_reference_t<_It2>>;
+
+template <class _Fp, class _It1, class _It2 = _It1>
+concept indirect_equivalence_relation =
+ indirectly_readable<_It1> && indirectly_readable<_It2> && copy_constructible<_Fp> &&
+ equivalence_relation<_Fp&, iter_value_t<_It1>&, iter_value_t<_It2>&> &&
+ equivalence_relation<_Fp&, iter_value_t<_It1>&, iter_reference_t<_It2>> &&
+ equivalence_relation<_Fp&, iter_reference_t<_It1>, iter_value_t<_It2>&> &&
+ equivalence_relation<_Fp&, iter_reference_t<_It1>, iter_reference_t<_It2>>;
+
+template <class _Fp, class _It1, class _It2 = _It1>
+concept indirect_strict_weak_order =
+ indirectly_readable<_It1> && indirectly_readable<_It2> && copy_constructible<_Fp> &&
+ strict_weak_order<_Fp&, iter_value_t<_It1>&, iter_value_t<_It2>&> &&
+ strict_weak_order<_Fp&, iter_value_t<_It1>&, iter_reference_t<_It2>> &&
+ strict_weak_order<_Fp&, iter_reference_t<_It1>, iter_value_t<_It2>&> &&
+ strict_weak_order<_Fp&, iter_reference_t<_It1>, iter_reference_t<_It2>>;
+
+template <class _Fp, class... _Its>
+ requires(indirectly_readable<_Its> && ...) && invocable<_Fp, iter_reference_t<_Its>...>
+using indirect_result_t = invoke_result_t<_Fp, iter_reference_t<_Its>...>;
+
+template <class _In, class _Out>
+concept indirectly_movable = indirectly_readable<_In> && indirectly_writable<_Out, iter_rvalue_reference_t<_In>>;
+
+template <class _In, class _Out>
+concept indirectly_movable_storable =
+ indirectly_movable<_In, _Out> && indirectly_writable<_Out, iter_value_t<_In>> && movable<iter_value_t<_In>> &&
+ constructible_from<iter_value_t<_In>, iter_rvalue_reference_t<_In>> &&
+ assignable_from<iter_value_t<_In>&, iter_rvalue_reference_t<_In>>;
+
+template <class _In, class _Out>
+concept indirectly_copyable = indirectly_readable<_In> && indirectly_writable<_Out, iter_reference_t<_In>>;
+
+template <class _In, class _Out>
+concept indirectly_copyable_storable =
+ indirectly_copyable<_In, _Out> && indirectly_writable<_Out, iter_value_t<_In>&> &&
+ indirectly_writable<_Out, const iter_value_t<_In>&> && indirectly_writable<_Out, iter_value_t<_In>&&> &&
+ indirectly_writable<_Out, const iter_value_t<_In>&&> && copyable<iter_value_t<_In>> &&
+ constructible_from<iter_value_t<_In>, iter_reference_t<_In>> &&
+ assignable_from<iter_value_t<_In>&, iter_reference_t<_In>>;
+
+// Note: indirectly_swappable is located in iter_swap.h to prevent a dependency cycle
+// (both iter_swap and indirectly_swappable require indirectly_readable).
+
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+using __has_random_access_iterator_category_or_concept
+#if _LIBCPP_STD_VER >= 20
+ = integral_constant<bool, random_access_iterator<_Tp>>;
+#else // _LIBCPP_STD_VER < 20
+ = __has_random_access_iterator_category<_Tp>;
+#endif // _LIBCPP_STD_VER
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_CONCEPTS_H
diff --git a/libcxx/include/__cxx03/__iterator/counted_iterator.h b/libcxx/include/__cxx03/__iterator/counted_iterator.h
new file mode 100644
index 00000000000000..ea2832e3b978dc
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/counted_iterator.h
@@ -0,0 +1,289 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_COUNTED_ITERATOR_H
+#define _LIBCPP___ITERATOR_COUNTED_ITERATOR_H
+
+#include <__assert>
+#include <__concepts/assignable.h>
+#include <__concepts/common_with.h>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/conditional.h>
+#include <__utility/move.h>
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class>
+struct __counted_iterator_concept {};
+
+template <class _Iter>
+ requires requires { typename _Iter::iterator_concept; }
+struct __counted_iterator_concept<_Iter> {
+ using iterator_concept = typename _Iter::iterator_concept;
+};
+
+template <class>
+struct __counted_iterator_category {};
+
+template <class _Iter>
+ requires requires { typename _Iter::iterator_category; }
+struct __counted_iterator_category<_Iter> {
+ using iterator_category = typename _Iter::iterator_category;
+};
+
+template <class>
+struct __counted_iterator_value_type {};
+
+template <indirectly_readable _Iter>
+struct __counted_iterator_value_type<_Iter> {
+ using value_type = iter_value_t<_Iter>;
+};
+
+template <input_or_output_iterator _Iter>
+class counted_iterator
+ : public __counted_iterator_concept<_Iter>,
+ public __counted_iterator_category<_Iter>,
+ public __counted_iterator_value_type<_Iter> {
+public:
+ using iterator_type = _Iter;
+ using difference_type = iter_difference_t<_Iter>;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator()
+ requires default_initializable<_Iter>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator(_Iter __iter, iter_difference_t<_Iter> __n)
+ : __current_(std::move(__iter)), __count_(__n) {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__n >= 0, "__n must not be negative.");
+ }
+
+ template <class _I2>
+ requires convertible_to<const _I2&, _Iter>
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator(const counted_iterator<_I2>& __other)
+ : __current_(__other.__current_), __count_(__other.__count_) {}
+
+ template <class _I2>
+ requires assignable_from<_Iter&, const _I2&>
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator=(const counted_iterator<_I2>& __other) {
+ __current_ = __other.__current_;
+ __count_ = __other.__count_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Iter& base() const& noexcept { return __current_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter base() && { return std::move(__current_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter> count() const noexcept { return __count_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count_ > 0, "Iterator is equal to or past end.");
+ return *__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const
+ requires __dereferenceable<const _Iter>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count_ > 0, "Iterator is equal to or past end.");
+ return *__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator->() const noexcept
+ requires contiguous_iterator<_Iter>
+ {
+ return std::to_address(__current_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator++() {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__count_ > 0, "Iterator already at or past end.");
+ ++__current_;
+ --__count_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator++(int) {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__count_ > 0, "Iterator already at or past end.");
+ --__count_;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+ return __current_++;
+ } catch (...) {
+ ++__count_;
+ throw;
+ }
+# else
+ return __current_++;
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator operator++(int)
+ requires forward_iterator<_Iter>
+ {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__count_ > 0, "Iterator already at or past end.");
+ counted_iterator __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator--()
+ requires bidirectional_iterator<_Iter>
+ {
+ --__current_;
+ ++__count_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator operator--(int)
+ requires bidirectional_iterator<_Iter>
+ {
+ counted_iterator __tmp = *this;
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator operator+(iter_difference_t<_Iter> __n) const
+ requires random_access_iterator<_Iter>
+ {
+ return counted_iterator(__current_ + __n, __count_ - __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr counted_iterator
+ operator+(iter_difference_t<_Iter> __n, const counted_iterator& __x)
+ requires random_access_iterator<_Iter>
+ {
+ return __x + __n;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator+=(iter_difference_t<_Iter> __n)
+ requires random_access_iterator<_Iter>
+ {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__n <= __count_, "Cannot advance iterator past end.");
+ __current_ += __n;
+ __count_ -= __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator operator-(iter_difference_t<_Iter> __n) const
+ requires random_access_iterator<_Iter>
+ {
+ return counted_iterator(__current_ - __n, __count_ + __n);
+ }
+
+ template <common_with<_Iter> _I2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_I2>
+ operator-(const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs) {
+ return __rhs.__count_ - __lhs.__count_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_Iter>
+ operator-(const counted_iterator& __lhs, default_sentinel_t) {
+ return -__lhs.__count_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_Iter>
+ operator-(default_sentinel_t, const counted_iterator& __rhs) {
+ return __rhs.__count_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator-=(iter_difference_t<_Iter> __n)
+ requires random_access_iterator<_Iter>
+ {
+ _LIBCPP_ASSERT_UNCATEGORIZED(
+ -__n <= __count_,
+ "Attempt to subtract too large of a size: "
+ "counted_iterator would be decremented before the "
+ "first element of its range.");
+ __current_ -= __n;
+ __count_ += __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator[](iter_difference_t<_Iter> __n) const
+ requires random_access_iterator<_Iter>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < __count_, "Subscript argument must be less than size.");
+ return __current_[__n];
+ }
+
+ template <common_with<_Iter> _I2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool
+ operator==(const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs) {
+ return __lhs.__count_ == __rhs.__count_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const counted_iterator& __lhs, default_sentinel_t) {
+ return __lhs.__count_ == 0;
+ }
+
+ template <common_with<_Iter> _I2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr strong_ordering
+ operator<=>(const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs) {
+ return __rhs.__count_ <=> __lhs.__count_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_rvalue_reference_t<_Iter>
+ iter_move(const counted_iterator& __i) noexcept(noexcept(ranges::iter_move(__i.__current_)))
+ requires input_iterator<_Iter>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i.__count_ > 0, "Iterator must not be past end of range.");
+ return ranges::iter_move(__i.__current_);
+ }
+
+ template <indirectly_swappable<_Iter> _I2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void
+ iter_swap(const counted_iterator& __x,
+ const counted_iterator<_I2>& __y) noexcept(noexcept(ranges::iter_swap(__x.__current_, __y.__current_))) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __x.__count_ > 0 && __y.__count_ > 0, "Iterators must not be past end of range.");
+ return ranges::iter_swap(__x.__current_, __y.__current_);
+ }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS _Iter __current_ = _Iter();
+ iter_difference_t<_Iter> __count_ = 0;
+ template <input_or_output_iterator _OtherIter>
+ friend class counted_iterator;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(counted_iterator);
+
+template <input_iterator _Iter>
+ requires same_as<_ITER_TRAITS<_Iter>, iterator_traits<_Iter>>
+struct iterator_traits<counted_iterator<_Iter>> : iterator_traits<_Iter> {
+ using pointer = conditional_t<contiguous_iterator<_Iter>, add_pointer_t<iter_reference_t<_Iter>>, void>;
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_COUNTED_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/cpp17_iterator_concepts.h b/libcxx/include/__cxx03/__iterator/cpp17_iterator_concepts.h
new file mode 100644
index 00000000000000..ba3536b6860991
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/cpp17_iterator_concepts.h
@@ -0,0 +1,190 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_CPP17_ITERATOR_CONCEPTS_H
+#define _LIBCPP___ITERATOR_CPP17_ITERATOR_CONCEPTS_H
+
+#include <__concepts/boolean_testable.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/is_void.h>
+#include <__utility/as_const.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+concept __cpp17_move_constructible = is_move_constructible_v<_Tp>;
+
+template <class _Tp>
+concept __cpp17_copy_constructible = __cpp17_move_constructible<_Tp> && is_copy_constructible_v<_Tp>;
+
+template <class _Tp>
+concept __cpp17_move_assignable = requires(_Tp __lhs, _Tp __rhs) {
+ { __lhs = std::move(__rhs) } -> same_as<_Tp&>;
+};
+
+template <class _Tp>
+concept __cpp17_copy_assignable = __cpp17_move_assignable<_Tp> && requires(_Tp __lhs, _Tp __rhs) {
+ { __lhs = __rhs } -> same_as<_Tp&>;
+ { __lhs = std::as_const(__rhs) } -> same_as<_Tp&>;
+};
+
+template <class _Tp>
+concept __cpp17_destructible = requires(_Tp __v) { __v.~_Tp(); };
+
+template <class _Tp>
+concept __cpp17_equality_comparable = requires(_Tp __lhs, _Tp __rhs) {
+ { __lhs == __rhs } -> __boolean_testable;
+ { std::as_const(__lhs) == __rhs } -> __boolean_testable;
+ { __lhs == std::as_const(__rhs) } -> __boolean_testable;
+ { std::as_const(__lhs) == std::as_const(__rhs) } -> __boolean_testable;
+};
+
+template <class _Tp>
+concept __cpp17_default_constructible = is_default_constructible_v<_Tp>;
+
+template <class _Iter>
+concept __cpp17_iterator =
+ __cpp17_copy_constructible<_Iter> && __cpp17_copy_assignable<_Iter> && __cpp17_destructible<_Iter> &&
+ (is_signed_v<__iter_diff_t<_Iter>> || is_void_v<__iter_diff_t<_Iter>>) && requires(_Iter __iter) {
+ { *__iter };
+ { ++__iter } -> same_as<_Iter&>;
+ };
+
+template <class _Iter>
+concept __cpp17_input_iterator =
+ __cpp17_iterator<_Iter> && __cpp17_equality_comparable<_Iter> && requires(_Iter __lhs, _Iter __rhs) {
+ { __lhs != __rhs } -> __boolean_testable;
+ { std::as_const(__lhs) != __rhs } -> __boolean_testable;
+ { __lhs != std::as_const(__rhs) } -> __boolean_testable;
+ { std::as_const(__lhs) != std::as_const(__rhs) } -> __boolean_testable;
+
+ { *__lhs } -> same_as<__iter_reference<_Iter>>;
+ { *std::as_const(__lhs) } -> same_as<__iter_reference<_Iter>>;
+
+ { ++__lhs } -> same_as<_Iter&>;
+ { (void)__lhs++ };
+ { *__lhs++ };
+ };
+
+template <class _Iter, class _WriteTo>
+concept __cpp17_output_iterator = __cpp17_iterator<_Iter> && requires(_Iter __iter, _WriteTo __write) {
+ { *__iter = std::forward<_WriteTo>(__write) };
+ { ++__iter } -> same_as<_Iter&>;
+ { __iter++ } -> convertible_to<const _Iter&>;
+ { *__iter++ = std::forward<_WriteTo>(__write) };
+};
+
+template <class _Iter>
+concept __cpp17_forward_iterator =
+ __cpp17_input_iterator<_Iter> && __cpp17_default_constructible<_Iter> && requires(_Iter __iter) {
+ { __iter++ } -> convertible_to<const _Iter&>;
+ { *__iter++ } -> same_as<__iter_reference<_Iter>>;
+ };
+
+template <class _Iter>
+concept __cpp17_bidirectional_iterator = __cpp17_forward_iterator<_Iter> && requires(_Iter __iter) {
+ { --__iter } -> same_as<_Iter&>;
+ { __iter-- } -> convertible_to<const _Iter&>;
+ { *__iter-- } -> same_as<__iter_reference<_Iter>>;
+};
+
+template <class _Iter>
+concept __cpp17_random_access_iterator =
+ __cpp17_bidirectional_iterator<_Iter> && requires(_Iter __iter, __iter_diff_t<_Iter> __n) {
+ { __iter += __n } -> same_as<_Iter&>;
+
+ { __iter + __n } -> same_as<_Iter>;
+ { __n + __iter } -> same_as<_Iter>;
+ { std::as_const(__iter) + __n } -> same_as<_Iter>;
+ { __n + std::as_const(__iter) } -> same_as<_Iter>;
+
+ { __iter -= __n } -> same_as<_Iter&>;
+ { __iter - __n } -> same_as<_Iter>;
+ { std::as_const(__iter) - __n } -> same_as<_Iter>;
+
+ { __iter - __iter } -> same_as<__iter_diff_t<_Iter>>;
+ { std::as_const(__iter) - __iter } -> same_as<__iter_diff_t<_Iter>>;
+ { __iter - std::as_const(__iter) } -> same_as<__iter_diff_t<_Iter>>;
+ { std::as_const(__iter) - std::as_const(__iter) } -> same_as<__iter_diff_t<_Iter>>;
+
+ { __iter[__n] } -> convertible_to<__iter_reference<_Iter>>;
+ { std::as_const(__iter)[__n] } -> convertible_to<__iter_reference<_Iter>>;
+
+ { __iter < __iter } -> __boolean_testable;
+ { std::as_const(__iter) < __iter } -> __boolean_testable;
+ { __iter < std::as_const(__iter) } -> __boolean_testable;
+ { std::as_const(__iter) < std::as_const(__iter) } -> __boolean_testable;
+
+ { __iter > __iter } -> __boolean_testable;
+ { std::as_const(__iter) > __iter } -> __boolean_testable;
+ { __iter > std::as_const(__iter) } -> __boolean_testable;
+ { std::as_const(__iter) > std::as_const(__iter) } -> __boolean_testable;
+
+ { __iter >= __iter } -> __boolean_testable;
+ { std::as_const(__iter) >= __iter } -> __boolean_testable;
+ { __iter >= std::as_const(__iter) } -> __boolean_testable;
+ { std::as_const(__iter) >= std::as_const(__iter) } -> __boolean_testable;
+
+ { __iter <= __iter } -> __boolean_testable;
+ { std::as_const(__iter) <= __iter } -> __boolean_testable;
+ { __iter <= std::as_const(__iter) } -> __boolean_testable;
+ { std::as_const(__iter) <= std::as_const(__iter) } -> __boolean_testable;
+ };
+
+_LIBCPP_END_NAMESPACE_STD
+
+# ifndef _LIBCPP_DISABLE_ITERATOR_CHECKS
+# define _LIBCPP_REQUIRE_CPP17_INPUT_ITERATOR(iter_t, message) \
+ static_assert(::std::__cpp17_input_iterator<iter_t>, message)
+# define _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(iter_t, write_t, message) \
+ static_assert(::std::__cpp17_output_iterator<iter_t, write_t>, message)
+# define _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(iter_t, message) \
+ static_assert(::std::__cpp17_forward_iterator<iter_t>, message)
+# define _LIBCPP_REQUIRE_CPP17_BIDIRECTIONAL_ITERATOR(iter_t, message) \
+ static_assert(::std::__cpp17_bidirectional_iterator<iter_t>, message)
+# define _LIBCPP_REQUIRE_CPP17_RANDOM_ACCESS_ITERATOR(iter_t, message) \
+ static_assert(::std::__cpp17_random_access_iterator<iter_t>, message)
+# else
+# define _LIBCPP_REQUIRE_CPP17_INPUT_ITERATOR(iter_t, message) static_assert(true)
+# define _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(iter_t, write_t, message) static_assert(true)
+# define _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(iter_t, message) static_assert(true)
+# define _LIBCPP_REQUIRE_CPP17_BIDIRECTIONAL_ITERATOR(iter_t, message) static_assert(true)
+# define _LIBCPP_REQUIRE_CPP17_RANDOM_ACCESS_ITERATOR(iter_t, message) static_assert(true)
+# endif
+
+#else // _LIBCPP_STD_VER >= 20
+
+# define _LIBCPP_REQUIRE_CPP17_INPUT_ITERATOR(iter_t, message) static_assert(true)
+# define _LIBCPP_REQUIRE_CPP17_OUTPUT_ITERATOR(iter_t, write_t, message) static_assert(true)
+# define _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(iter_t, message) static_assert(true)
+# define _LIBCPP_REQUIRE_CPP17_BIDIRECTIONAL_ITERATOR(iter_t, message) static_assert(true)
+# define _LIBCPP_REQUIRE_CPP17_RANDOM_ACCESS_ITERATOR(iter_t, message) static_assert(true)
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_CPP17_ITERATOR_CONCEPTS_H
diff --git a/libcxx/include/__cxx03/__iterator/data.h b/libcxx/include/__cxx03/__iterator/data.h
new file mode 100644
index 00000000000000..b7c1603652b0e6
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/data.h
@@ -0,0 +1,49 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_DATA_H
+#define _LIBCPP___ITERATOR_DATA_H
+
+#include <__config>
+#include <cstddef>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Cont>
+constexpr _LIBCPP_HIDE_FROM_ABI auto data(_Cont& __c) noexcept(noexcept(__c.data())) -> decltype(__c.data()) {
+ return __c.data();
+}
+
+template <class _Cont>
+constexpr _LIBCPP_HIDE_FROM_ABI auto data(const _Cont& __c) noexcept(noexcept(__c.data())) -> decltype(__c.data()) {
+ return __c.data();
+}
+
+template <class _Tp, size_t _Sz>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp* data(_Tp (&__array)[_Sz]) noexcept {
+ return __array;
+}
+
+template <class _Ep>
+_LIBCPP_HIDE_FROM_ABI constexpr const _Ep* data(initializer_list<_Ep> __il) noexcept {
+ return __il.begin();
+}
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_DATA_H
diff --git a/libcxx/include/__cxx03/__iterator/default_sentinel.h b/libcxx/include/__cxx03/__iterator/default_sentinel.h
new file mode 100644
index 00000000000000..3b65f442f1a85b
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/default_sentinel.h
@@ -0,0 +1,30 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_DEFAULT_SENTINEL_H
+#define _LIBCPP___ITERATOR_DEFAULT_SENTINEL_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+struct default_sentinel_t {};
+inline constexpr default_sentinel_t default_sentinel{};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_DEFAULT_SENTINEL_H
diff --git a/libcxx/include/__cxx03/__iterator/distance.h b/libcxx/include/__cxx03/__iterator/distance.h
new file mode 100644
index 00000000000000..75bd49c9ae732b
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/distance.h
@@ -0,0 +1,99 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_DISTANCE_H
+#define _LIBCPP___ITERATOR_DISTANCE_H
+
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/size.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/remove_cvref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 typename iterator_traits<_InputIter>::difference_type
+__distance(_InputIter __first, _InputIter __last, input_iterator_tag) {
+ typename iterator_traits<_InputIter>::difference_type __r(0);
+ for (; __first != __last; ++__first)
+ ++__r;
+ return __r;
+}
+
+template <class _RandIter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 typename iterator_traits<_RandIter>::difference_type
+__distance(_RandIter __first, _RandIter __last, random_access_iterator_tag) {
+ return __last - __first;
+}
+
+template <class _InputIter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 typename iterator_traits<_InputIter>::difference_type
+distance(_InputIter __first, _InputIter __last) {
+ return std::__distance(__first, __last, typename iterator_traits<_InputIter>::iterator_category());
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+// [range.iter.op.distance]
+
+namespace ranges {
+namespace __distance {
+
+struct __fn {
+ template <class _Ip, sentinel_for<_Ip> _Sp>
+ requires(!sized_sentinel_for<_Sp, _Ip>)
+ _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Ip> operator()(_Ip __first, _Sp __last) const {
+ iter_difference_t<_Ip> __n = 0;
+ while (__first != __last) {
+ ++__first;
+ ++__n;
+ }
+ return __n;
+ }
+
+ template <class _Ip, sized_sentinel_for<decay_t<_Ip>> _Sp>
+ _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Ip> operator()(_Ip&& __first, _Sp __last) const {
+ if constexpr (sized_sentinel_for<_Sp, __remove_cvref_t<_Ip>>) {
+ return __last - __first;
+ } else {
+ return __last - decay_t<_Ip>(__first);
+ }
+ }
+
+ template <range _Rp>
+ _LIBCPP_HIDE_FROM_ABI constexpr range_difference_t<_Rp> operator()(_Rp&& __r) const {
+ if constexpr (sized_range<_Rp>) {
+ return static_cast<range_difference_t<_Rp>>(ranges::size(__r));
+ } else {
+ return operator()(ranges::begin(__r), ranges::end(__r));
+ }
+ }
+};
+
+} // namespace __distance
+
+inline namespace __cpo {
+inline constexpr auto distance = __distance::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_DISTANCE_H
diff --git a/libcxx/include/__cxx03/__iterator/empty.h b/libcxx/include/__cxx03/__iterator/empty.h
new file mode 100644
index 00000000000000..773f2776955b2a
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/empty.h
@@ -0,0 +1,45 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_EMPTY_H
+#define _LIBCPP___ITERATOR_EMPTY_H
+
+#include <__config>
+#include <cstddef>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Cont>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto
+empty(const _Cont& __c) noexcept(noexcept(__c.empty())) -> decltype(__c.empty()) {
+ return __c.empty();
+}
+
+template <class _Tp, size_t _Sz>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty(const _Tp (&)[_Sz]) noexcept {
+ return false;
+}
+
+template <class _Ep>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty(initializer_list<_Ep> __il) noexcept {
+ return __il.size() == 0;
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_EMPTY_H
diff --git a/libcxx/include/__cxx03/__iterator/erase_if_container.h b/libcxx/include/__cxx03/__iterator/erase_if_container.h
new file mode 100644
index 00000000000000..0f87f50cd1c160
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/erase_if_container.h
@@ -0,0 +1,43 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ERASE_IF_CONTAINER_H
+#define _LIBCPP___ITERATOR_ERASE_IF_CONTAINER_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Container, class _Predicate>
+_LIBCPP_HIDE_FROM_ABI typename _Container::size_type __libcpp_erase_if_container(_Container& __c, _Predicate& __pred) {
+ typename _Container::size_type __old_size = __c.size();
+
+ const typename _Container::iterator __last = __c.end();
+ for (typename _Container::iterator __iter = __c.begin(); __iter != __last;) {
+ if (__pred(*__iter))
+ __iter = __c.erase(__iter);
+ else
+ ++__iter;
+ }
+
+ return __old_size - __c.size();
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_ERASE_IF_CONTAINER_H
diff --git a/libcxx/include/__cxx03/__iterator/front_insert_iterator.h b/libcxx/include/__cxx03/__iterator/front_insert_iterator.h
new file mode 100644
index 00000000000000..7f2c54ec87442e
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/front_insert_iterator.h
@@ -0,0 +1,83 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_FRONT_INSERT_ITERATOR_H
+#define _LIBCPP___ITERATOR_FRONT_INSERT_ITERATOR_H
+
+#include <__config>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Container>
+class _LIBCPP_TEMPLATE_VIS front_insert_iterator
+#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<output_iterator_tag, void, void, void, void>
+#endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ _Container* container;
+
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+#if _LIBCPP_STD_VER >= 20
+ typedef ptrdiff_t difference_type;
+#else
+ typedef void difference_type;
+#endif
+ typedef void pointer;
+ typedef void reference;
+ typedef _Container container_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit front_insert_iterator(_Container& __x)
+ : container(std::addressof(__x)) {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 front_insert_iterator&
+ operator=(const typename _Container::value_type& __value) {
+ container->push_front(__value);
+ return *this;
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 front_insert_iterator&
+ operator=(typename _Container::value_type&& __value) {
+ container->push_front(std::move(__value));
+ return *this;
+ }
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 front_insert_iterator& operator*() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 front_insert_iterator& operator++() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 front_insert_iterator operator++(int) { return *this; }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(front_insert_iterator);
+
+template <class _Container>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 front_insert_iterator<_Container>
+front_inserter(_Container& __x) {
+ return front_insert_iterator<_Container>(__x);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_FRONT_INSERT_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/incrementable_traits.h b/libcxx/include/__cxx03/__iterator/incrementable_traits.h
new file mode 100644
index 00000000000000..a228b228f6e552
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/incrementable_traits.h
@@ -0,0 +1,79 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_INCREMENTABLE_TRAITS_H
+#define _LIBCPP___ITERATOR_INCREMENTABLE_TRAITS_H
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_primary_template.h>
+#include <__type_traits/make_signed.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/declval.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [incrementable.traits]
+template <class>
+struct incrementable_traits {};
+
+template <class _Tp>
+ requires is_object_v<_Tp>
+struct incrementable_traits<_Tp*> {
+ using difference_type = ptrdiff_t;
+};
+
+template <class _Ip>
+struct incrementable_traits<const _Ip> : incrementable_traits<_Ip> {};
+
+template <class _Tp>
+concept __has_member_difference_type = requires { typename _Tp::difference_type; };
+
+template <__has_member_difference_type _Tp>
+struct incrementable_traits<_Tp> {
+ using difference_type = typename _Tp::difference_type;
+};
+
+template <class _Tp>
+concept __has_integral_minus = requires(const _Tp& __x, const _Tp& __y) {
+ { __x - __y } -> integral;
+};
+
+template <__has_integral_minus _Tp>
+ requires(!__has_member_difference_type<_Tp>)
+struct incrementable_traits<_Tp> {
+ using difference_type = make_signed_t<decltype(std::declval<_Tp>() - std::declval<_Tp>())>;
+};
+
+template <class>
+struct iterator_traits;
+
+// Let `RI` be `remove_cvref_t<I>`. The type `iter_difference_t<I>` denotes
+// `incrementable_traits<RI>::difference_type` if `iterator_traits<RI>` names a specialization
+// generated from the primary template, and `iterator_traits<RI>::difference_type` otherwise.
+template <class _Ip>
+using iter_difference_t =
+ typename conditional_t<__is_primary_template<iterator_traits<remove_cvref_t<_Ip> > >::value,
+ incrementable_traits<remove_cvref_t<_Ip> >,
+ iterator_traits<remove_cvref_t<_Ip> > >::difference_type;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_INCREMENTABLE_TRAITS_H
diff --git a/libcxx/include/__cxx03/__iterator/indirectly_comparable.h b/libcxx/include/__cxx03/__iterator/indirectly_comparable.h
new file mode 100644
index 00000000000000..e8a7398bacd2b0
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/indirectly_comparable.h
@@ -0,0 +1,33 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_INDIRECTLY_COMPARABLE_H
+#define _LIBCPP___ITERATOR_INDIRECTLY_COMPARABLE_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _I1, class _I2, class _Rp, class _P1 = identity, class _P2 = identity>
+concept indirectly_comparable = indirect_binary_predicate<_Rp, projected<_I1, _P1>, projected<_I2, _P2>>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_INDIRECTLY_COMPARABLE_H
diff --git a/libcxx/include/__cxx03/__iterator/insert_iterator.h b/libcxx/include/__cxx03/__iterator/insert_iterator.h
new file mode 100644
index 00000000000000..8b7574dc9ec0af
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/insert_iterator.h
@@ -0,0 +1,95 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_INSERT_ITERATOR_H
+#define _LIBCPP___ITERATOR_INSERT_ITERATOR_H
+
+#include <__config>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Container>
+using __insert_iterator_iter_t = ranges::iterator_t<_Container>;
+#else
+template <class _Container>
+using __insert_iterator_iter_t = typename _Container::iterator;
+#endif
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Container>
+class _LIBCPP_TEMPLATE_VIS insert_iterator
+#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<output_iterator_tag, void, void, void, void>
+#endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ _Container* container;
+ __insert_iterator_iter_t<_Container> iter;
+
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+#if _LIBCPP_STD_VER >= 20
+ typedef ptrdiff_t difference_type;
+#else
+ typedef void difference_type;
+#endif
+ typedef void pointer;
+ typedef void reference;
+ typedef _Container container_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ insert_iterator(_Container& __x, __insert_iterator_iter_t<_Container> __i)
+ : container(std::addressof(__x)), iter(__i) {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 insert_iterator&
+ operator=(const typename _Container::value_type& __value) {
+ iter = container->insert(iter, __value);
+ ++iter;
+ return *this;
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 insert_iterator&
+ operator=(typename _Container::value_type&& __value) {
+ iter = container->insert(iter, std::move(__value));
+ ++iter;
+ return *this;
+ }
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 insert_iterator& operator*() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 insert_iterator& operator++() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 insert_iterator& operator++(int) { return *this; }
+};
+
+template <class _Container>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 insert_iterator<_Container>
+inserter(_Container& __x, __insert_iterator_iter_t<_Container> __i) {
+ return insert_iterator<_Container>(__x, __i);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_INSERT_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/istream_iterator.h b/libcxx/include/__cxx03/__iterator/istream_iterator.h
new file mode 100644
index 00000000000000..58c9ac6d4cccea
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/istream_iterator.h
@@ -0,0 +1,101 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ISTREAM_ITERATOR_H
+#define _LIBCPP___ITERATOR_ISTREAM_ITERATOR_H
+
+#include <__config>
+#include <__fwd/istream.h>
+#include <__fwd/string.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Tp, class _CharT = char, class _Traits = char_traits<_CharT>, class _Distance = ptrdiff_t>
+class _LIBCPP_TEMPLATE_VIS istream_iterator
+#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<input_iterator_tag, _Tp, _Distance, const _Tp*, const _Tp&>
+#endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ typedef input_iterator_tag iterator_category;
+ typedef _Tp value_type;
+ typedef _Distance difference_type;
+ typedef const _Tp* pointer;
+ typedef const _Tp& reference;
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef basic_istream<_CharT, _Traits> istream_type;
+
+private:
+ istream_type* __in_stream_;
+ _Tp __value_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR istream_iterator() : __in_stream_(nullptr), __value_() {}
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr istream_iterator(default_sentinel_t) : istream_iterator() {}
+#endif // _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI istream_iterator(istream_type& __s) : __in_stream_(std::addressof(__s)) {
+ if (!(*__in_stream_ >> __value_))
+ __in_stream_ = nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const _Tp& operator*() const { return __value_; }
+ _LIBCPP_HIDE_FROM_ABI const _Tp* operator->() const { return std::addressof((operator*())); }
+ _LIBCPP_HIDE_FROM_ABI istream_iterator& operator++() {
+ if (!(*__in_stream_ >> __value_))
+ __in_stream_ = nullptr;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI istream_iterator operator++(int) {
+ istream_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ template <class _Up, class _CharU, class _TraitsU, class _DistanceU>
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator<_Up, _CharU, _TraitsU, _DistanceU>& __x,
+ const istream_iterator<_Up, _CharU, _TraitsU, _DistanceU>& __y);
+
+#if _LIBCPP_STD_VER >= 20
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator& __i, default_sentinel_t) {
+ return __i.__in_stream_ == nullptr;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+};
+
+template <class _Tp, class _CharT, class _Traits, class _Distance>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __x,
+ const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __y) {
+ return __x.__in_stream_ == __y.__in_stream_;
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _Tp, class _CharT, class _Traits, class _Distance>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __x,
+ const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __y) {
+ return !(__x == __y);
+}
+#endif // _LIBCPP_STD_VER <= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_ISTREAM_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/istreambuf_iterator.h b/libcxx/include/__cxx03/__iterator/istreambuf_iterator.h
new file mode 100644
index 00000000000000..51c4ecff351f52
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/istreambuf_iterator.h
@@ -0,0 +1,109 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ISTREAMBUF_ITERATOR_H
+#define _LIBCPP___ITERATOR_ISTREAMBUF_ITERATOR_H
+
+#include <__config>
+#include <__fwd/istream.h>
+#include <__fwd/streambuf.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS istreambuf_iterator
+#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<input_iterator_tag, _CharT, typename _Traits::off_type, _CharT*, _CharT>
+#endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ typedef input_iterator_tag iterator_category;
+ typedef _CharT value_type;
+ typedef typename _Traits::off_type difference_type;
+ typedef _CharT* pointer;
+ typedef _CharT reference;
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename _Traits::int_type int_type;
+ typedef basic_streambuf<_CharT, _Traits> streambuf_type;
+ typedef basic_istream<_CharT, _Traits> istream_type;
+
+private:
+ mutable streambuf_type* __sbuf_;
+
+ class __proxy {
+ char_type __keep_;
+ streambuf_type* __sbuf_;
+ _LIBCPP_HIDE_FROM_ABI explicit __proxy(char_type __c, streambuf_type* __s) : __keep_(__c), __sbuf_(__s) {}
+ friend class istreambuf_iterator;
+
+ public:
+ _LIBCPP_HIDE_FROM_ABI char_type operator*() const { return __keep_; }
+ };
+
+ _LIBCPP_HIDE_FROM_ABI bool __test_for_eof() const {
+ if (__sbuf_ && traits_type::eq_int_type(__sbuf_->sgetc(), traits_type::eof()))
+ __sbuf_ = nullptr;
+ return __sbuf_ == nullptr;
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR istreambuf_iterator() _NOEXCEPT : __sbuf_(nullptr) {}
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr istreambuf_iterator(default_sentinel_t) noexcept : istreambuf_iterator() {}
+#endif // _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI istreambuf_iterator(istream_type& __s) _NOEXCEPT : __sbuf_(__s.rdbuf()) {}
+ _LIBCPP_HIDE_FROM_ABI istreambuf_iterator(streambuf_type* __s) _NOEXCEPT : __sbuf_(__s) {}
+ _LIBCPP_HIDE_FROM_ABI istreambuf_iterator(const __proxy& __p) _NOEXCEPT : __sbuf_(__p.__sbuf_) {}
+
+ _LIBCPP_HIDE_FROM_ABI char_type operator*() const { return static_cast<char_type>(__sbuf_->sgetc()); }
+ _LIBCPP_HIDE_FROM_ABI istreambuf_iterator& operator++() {
+ __sbuf_->sbumpc();
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __proxy operator++(int) { return __proxy(__sbuf_->sbumpc(), __sbuf_); }
+
+ _LIBCPP_HIDE_FROM_ABI bool equal(const istreambuf_iterator& __b) const {
+ return __test_for_eof() == __b.__test_for_eof();
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const istreambuf_iterator& __i, default_sentinel_t) {
+ return __i.__test_for_eof();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+};
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const istreambuf_iterator<_CharT, _Traits>& __a, const istreambuf_iterator<_CharT, _Traits>& __b) {
+ return __a.equal(__b);
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const istreambuf_iterator<_CharT, _Traits>& __a, const istreambuf_iterator<_CharT, _Traits>& __b) {
+ return !__a.equal(__b);
+}
+#endif // _LIBCPP_STD_VER <= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_ISTREAMBUF_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/iter_move.h b/libcxx/include/__cxx03/__iterator/iter_move.h
new file mode 100644
index 00000000000000..ba8aed3c0ffbbd
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/iter_move.h
@@ -0,0 +1,103 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ITER_MOVE_H
+#define _LIBCPP___ITERATOR_ITER_MOVE_H
+
+#include <__concepts/class_or_enum.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [iterator.cust.move]
+
+namespace ranges {
+namespace __iter_move {
+
+void iter_move() = delete;
+
+template <class _Tp>
+concept __unqualified_iter_move = __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) {
+ // NOLINTNEXTLINE(libcpp-robust-against-adl) iter_swap ADL calls should only be made through ranges::iter_swap
+ iter_move(std::forward<_Tp>(__t));
+};
+
+template <class _Tp>
+concept __move_deref = !__unqualified_iter_move<_Tp> && requires(_Tp&& __t) {
+ *__t;
+ requires is_lvalue_reference_v<decltype(*__t)>;
+};
+
+template <class _Tp>
+concept __just_deref = !__unqualified_iter_move<_Tp> && !__move_deref<_Tp> && requires(_Tp&& __t) {
+ *__t;
+ requires(!is_lvalue_reference_v<decltype(*__t)>);
+};
+
+// [iterator.cust.move]
+
+struct __fn {
+ // NOLINTBEGIN(libcpp-robust-against-adl) iter_move ADL calls should only be made through ranges::iter_move
+ template <class _Ip>
+ requires __unqualified_iter_move<_Ip>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator()(_Ip&& __i) const
+ noexcept(noexcept(iter_move(std::forward<_Ip>(__i)))) {
+ return iter_move(std::forward<_Ip>(__i));
+ }
+ // NOLINTEND(libcpp-robust-against-adl)
+
+ template <class _Ip>
+ requires __move_deref<_Ip>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Ip&& __i) const
+ noexcept(noexcept(std::move(*std::forward<_Ip>(__i)))) -> decltype(std::move(*std::forward<_Ip>(__i))) {
+ return std::move(*std::forward<_Ip>(__i));
+ }
+
+ template <class _Ip>
+ requires __just_deref<_Ip>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Ip&& __i) const
+ noexcept(noexcept(*std::forward<_Ip>(__i))) -> decltype(*std::forward<_Ip>(__i)) {
+ return *std::forward<_Ip>(__i);
+ }
+};
+} // namespace __iter_move
+
+inline namespace __cpo {
+inline constexpr auto iter_move = __iter_move::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+template <__dereferenceable _Tp>
+ requires requires(_Tp& __t) {
+ { ranges::iter_move(__t) } -> __can_reference;
+ }
+using iter_rvalue_reference_t = decltype(ranges::iter_move(std::declval<_Tp&>()));
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_ITER_MOVE_H
diff --git a/libcxx/include/__cxx03/__iterator/iter_swap.h b/libcxx/include/__cxx03/__iterator/iter_swap.h
new file mode 100644
index 00000000000000..01ab1b97d6501f
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/iter_swap.h
@@ -0,0 +1,108 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ITER_SWAP_H
+#define _LIBCPP___ITERATOR_ITER_SWAP_H
+
+#include <__concepts/class_or_enum.h>
+#include <__concepts/swappable.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [iter.cust.swap]
+
+namespace ranges {
+namespace __iter_swap {
+template <class _I1, class _I2>
+void iter_swap(_I1, _I2) = delete;
+
+template <class _T1, class _T2>
+concept __unqualified_iter_swap =
+ (__class_or_enum<remove_cvref_t<_T1>> || __class_or_enum<remove_cvref_t<_T2>>) && requires(_T1&& __x, _T2&& __y) {
+ // NOLINTNEXTLINE(libcpp-robust-against-adl) iter_swap ADL calls should only be made through ranges::iter_swap
+ iter_swap(std::forward<_T1>(__x), std::forward<_T2>(__y));
+ };
+
+template <class _T1, class _T2>
+concept __readable_swappable =
+ indirectly_readable<_T1> && indirectly_readable<_T2> &&
+ swappable_with<iter_reference_t<_T1>, iter_reference_t<_T2>>;
+
+struct __fn {
+ // NOLINTBEGIN(libcpp-robust-against-adl) iter_swap ADL calls should only be made through ranges::iter_swap
+ template <class _T1, class _T2>
+ requires __unqualified_iter_swap<_T1, _T2>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_T1&& __x, _T2&& __y) const
+ noexcept(noexcept(iter_swap(std::forward<_T1>(__x), std::forward<_T2>(__y)))) {
+ (void)iter_swap(std::forward<_T1>(__x), std::forward<_T2>(__y));
+ }
+ // NOLINTEND(libcpp-robust-against-adl)
+
+ template <class _T1, class _T2>
+ requires(!__unqualified_iter_swap<_T1, _T2>) && __readable_swappable<_T1, _T2>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_T1&& __x, _T2&& __y) const
+ noexcept(noexcept(ranges::swap(*std::forward<_T1>(__x), *std::forward<_T2>(__y)))) {
+ ranges::swap(*std::forward<_T1>(__x), *std::forward<_T2>(__y));
+ }
+
+ template <class _T1, class _T2>
+ requires(!__unqualified_iter_swap<_T1, _T2> && //
+ !__readable_swappable<_T1, _T2>) && //
+ indirectly_movable_storable<_T1, _T2> && //
+ indirectly_movable_storable<_T2, _T1>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_T1&& __x, _T2&& __y) const
+ noexcept(noexcept(iter_value_t<_T2>(ranges::iter_move(__y))) && //
+ noexcept(*__y = ranges::iter_move(__x)) && //
+ noexcept(*std::forward<_T1>(__x) = std::declval<iter_value_t<_T2>>())) {
+ iter_value_t<_T2> __old(ranges::iter_move(__y));
+ *__y = ranges::iter_move(__x);
+ *std::forward<_T1>(__x) = std::move(__old);
+ }
+};
+} // namespace __iter_swap
+
+inline namespace __cpo {
+inline constexpr auto iter_swap = __iter_swap::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+template <class _I1, class _I2 = _I1>
+concept indirectly_swappable =
+ indirectly_readable<_I1> && indirectly_readable<_I2> && requires(const _I1 __i1, const _I2 __i2) {
+ ranges::iter_swap(__i1, __i1);
+ ranges::iter_swap(__i2, __i2);
+ ranges::iter_swap(__i1, __i2);
+ ranges::iter_swap(__i2, __i1);
+ };
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_ITER_SWAP_H
diff --git a/libcxx/include/__cxx03/__iterator/iterator.h b/libcxx/include/__cxx03/__iterator/iterator.h
new file mode 100644
index 00000000000000..ba9308f3c22430
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/iterator.h
@@ -0,0 +1,33 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ITERATOR_H
+#define _LIBCPP___ITERATOR_ITERATOR_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Category, class _Tp, class _Distance = ptrdiff_t, class _Pointer = _Tp*, class _Reference = _Tp&>
+struct _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 iterator {
+ typedef _Tp value_type;
+ typedef _Distance difference_type;
+ typedef _Pointer pointer;
+ typedef _Reference reference;
+ typedef _Category iterator_category;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/iterator_traits.h b/libcxx/include/__cxx03/__iterator/iterator_traits.h
new file mode 100644
index 00000000000000..11af9e301842cf
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/iterator_traits.h
@@ -0,0 +1,528 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ITERATOR_TRAITS_H
+#define _LIBCPP___ITERATOR_ITERATOR_TRAITS_H
+
+#include <__concepts/arithmetic.h>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/copyable.h>
+#include <__concepts/equality_comparable.h>
+#include <__concepts/same_as.h>
+#include <__concepts/totally_ordered.h>
+#include <__config>
+#include <__fwd/pair.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__type_traits/common_reference.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/disjunction.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_primary_template.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_valid_expansion.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+using __with_reference = _Tp&;
+
+template <class _Tp>
+concept __can_reference = requires { typename __with_reference<_Tp>; };
+
+template <class _Tp>
+concept __dereferenceable = requires(_Tp& __t) {
+ { *__t } -> __can_reference; // not required to be equality-preserving
+};
+
+// [iterator.traits]
+template <__dereferenceable _Tp>
+using iter_reference_t = decltype(*std::declval<_Tp&>());
+
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Iter>
+struct _LIBCPP_TEMPLATE_VIS iterator_traits;
+
+struct _LIBCPP_TEMPLATE_VIS input_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS output_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS forward_iterator_tag : public input_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS bidirectional_iterator_tag : public forward_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS random_access_iterator_tag : public bidirectional_iterator_tag {};
+#if _LIBCPP_STD_VER >= 20
+struct _LIBCPP_TEMPLATE_VIS contiguous_iterator_tag : public random_access_iterator_tag {};
+#endif
+
+template <class _Iter>
+struct __iter_traits_cache {
+ using type = _If< __is_primary_template<iterator_traits<_Iter> >::value, _Iter, iterator_traits<_Iter> >;
+};
+template <class _Iter>
+using _ITER_TRAITS = typename __iter_traits_cache<_Iter>::type;
+
+struct __iter_concept_concept_test {
+ template <class _Iter>
+ using _Apply = typename _ITER_TRAITS<_Iter>::iterator_concept;
+};
+struct __iter_concept_category_test {
+ template <class _Iter>
+ using _Apply = typename _ITER_TRAITS<_Iter>::iterator_category;
+};
+struct __iter_concept_random_fallback {
+ template <class _Iter>
+ using _Apply = __enable_if_t< __is_primary_template<iterator_traits<_Iter> >::value, random_access_iterator_tag >;
+};
+
+template <class _Iter, class _Tester>
+struct __test_iter_concept : _IsValidExpansion<_Tester::template _Apply, _Iter>, _Tester {};
+
+template <class _Iter>
+struct __iter_concept_cache {
+ using type = _Or< __test_iter_concept<_Iter, __iter_concept_concept_test>,
+ __test_iter_concept<_Iter, __iter_concept_category_test>,
+ __test_iter_concept<_Iter, __iter_concept_random_fallback> >;
+};
+
+template <class _Iter>
+using _ITER_CONCEPT = typename __iter_concept_cache<_Iter>::type::template _Apply<_Iter>;
+
+template <class _Tp>
+struct __has_iterator_typedefs {
+private:
+ template <class _Up>
+ static false_type __test(...);
+ template <class _Up>
+ static true_type
+ __test(__void_t<typename _Up::iterator_category>* = nullptr,
+ __void_t<typename _Up::difference_type>* = nullptr,
+ __void_t<typename _Up::value_type>* = nullptr,
+ __void_t<typename _Up::reference>* = nullptr,
+ __void_t<typename _Up::pointer>* = nullptr);
+
+public:
+ static const bool value = decltype(__test<_Tp>(nullptr, nullptr, nullptr, nullptr, nullptr))::value;
+};
+
+template <class _Tp>
+struct __has_iterator_category {
+private:
+ template <class _Up>
+ static false_type __test(...);
+ template <class _Up>
+ static true_type __test(typename _Up::iterator_category* = nullptr);
+
+public:
+ static const bool value = decltype(__test<_Tp>(nullptr))::value;
+};
+
+template <class _Tp>
+struct __has_iterator_concept {
+private:
+ template <class _Up>
+ static false_type __test(...);
+ template <class _Up>
+ static true_type __test(typename _Up::iterator_concept* = nullptr);
+
+public:
+ static const bool value = decltype(__test<_Tp>(nullptr))::value;
+};
+
+#if _LIBCPP_STD_VER >= 20
+
+// The `cpp17-*-iterator` exposition-only concepts have very similar names to the `Cpp17*Iterator` named requirements
+// from `[iterator.cpp17]`. To avoid confusion between the two, the exposition-only concepts have been banished to
+// a "detail" namespace indicating they have a niche use-case.
+namespace __iterator_traits_detail {
+template <class _Ip>
+concept __cpp17_iterator = requires(_Ip __i) {
+ { *__i } -> __can_reference;
+ { ++__i } -> same_as<_Ip&>;
+ { *__i++ } -> __can_reference;
+} && copyable<_Ip>;
+
+template <class _Ip>
+concept __cpp17_input_iterator = __cpp17_iterator<_Ip> && equality_comparable<_Ip> && requires(_Ip __i) {
+ typename incrementable_traits<_Ip>::difference_type;
+ typename indirectly_readable_traits<_Ip>::value_type;
+ typename common_reference_t<iter_reference_t<_Ip>&&, typename indirectly_readable_traits<_Ip>::value_type&>;
+ typename common_reference_t<decltype(*__i++)&&, typename indirectly_readable_traits<_Ip>::value_type&>;
+ requires signed_integral<typename incrementable_traits<_Ip>::difference_type>;
+};
+
+template <class _Ip>
+concept __cpp17_forward_iterator =
+ __cpp17_input_iterator<_Ip> && constructible_from<_Ip> && is_reference_v<iter_reference_t<_Ip>> &&
+ same_as<remove_cvref_t<iter_reference_t<_Ip>>, typename indirectly_readable_traits<_Ip>::value_type> &&
+ requires(_Ip __i) {
+ { __i++ } -> convertible_to<_Ip const&>;
+ { *__i++ } -> same_as<iter_reference_t<_Ip>>;
+ };
+
+template <class _Ip>
+concept __cpp17_bidirectional_iterator = __cpp17_forward_iterator<_Ip> && requires(_Ip __i) {
+ { --__i } -> same_as<_Ip&>;
+ { __i-- } -> convertible_to<_Ip const&>;
+ { *__i-- } -> same_as<iter_reference_t<_Ip>>;
+};
+
+template <class _Ip>
+concept __cpp17_random_access_iterator =
+ __cpp17_bidirectional_iterator<_Ip> && totally_ordered<_Ip> &&
+ requires(_Ip __i, typename incrementable_traits<_Ip>::difference_type __n) {
+ { __i += __n } -> same_as<_Ip&>;
+ { __i -= __n } -> same_as<_Ip&>;
+ { __i + __n } -> same_as<_Ip>;
+ { __n + __i } -> same_as<_Ip>;
+ { __i - __n } -> same_as<_Ip>;
+ { __i - __i } -> same_as<decltype(__n)>; // NOLINT(misc-redundant-expression) ; This is llvm.org/PR54114
+ { __i[__n] } -> convertible_to<iter_reference_t<_Ip>>;
+ };
+} // namespace __iterator_traits_detail
+
+template <class _Ip>
+concept __has_member_reference = requires { typename _Ip::reference; };
+
+template <class _Ip>
+concept __has_member_pointer = requires { typename _Ip::pointer; };
+
+template <class _Ip>
+concept __has_member_iterator_category = requires { typename _Ip::iterator_category; };
+
+template <class _Ip>
+concept __specifies_members = requires {
+ typename _Ip::value_type;
+ typename _Ip::difference_type;
+ requires __has_member_reference<_Ip>;
+ requires __has_member_iterator_category<_Ip>;
+};
+
+template <class>
+struct __iterator_traits_member_pointer_or_void {
+ using type = void;
+};
+
+template <__has_member_pointer _Tp>
+struct __iterator_traits_member_pointer_or_void<_Tp> {
+ using type = typename _Tp::pointer;
+};
+
+template <class _Tp>
+concept __cpp17_iterator_missing_members = !__specifies_members<_Tp> && __iterator_traits_detail::__cpp17_iterator<_Tp>;
+
+template <class _Tp>
+concept __cpp17_input_iterator_missing_members =
+ __cpp17_iterator_missing_members<_Tp> && __iterator_traits_detail::__cpp17_input_iterator<_Tp>;
+
+// Otherwise, `pointer` names `void`.
+template <class>
+struct __iterator_traits_member_pointer_or_arrow_or_void {
+ using type = void;
+};
+
+// [iterator.traits]/3.2.1
+// If the qualified-id `I::pointer` is valid and denotes a type, `pointer` names that type.
+template <__has_member_pointer _Ip>
+struct __iterator_traits_member_pointer_or_arrow_or_void<_Ip> {
+ using type = typename _Ip::pointer;
+};
+
+// Otherwise, if `decltype(declval<I&>().operator->())` is well-formed, then `pointer` names that
+// type.
+template <class _Ip>
+ requires requires(_Ip& __i) { __i.operator->(); } && (!__has_member_pointer<_Ip>)
+struct __iterator_traits_member_pointer_or_arrow_or_void<_Ip> {
+ using type = decltype(std::declval<_Ip&>().operator->());
+};
+
+// Otherwise, `reference` names `iter-reference-t<I>`.
+template <class _Ip>
+struct __iterator_traits_member_reference {
+ using type = iter_reference_t<_Ip>;
+};
+
+// [iterator.traits]/3.2.2
+// If the qualified-id `I::reference` is valid and denotes a type, `reference` names that type.
+template <__has_member_reference _Ip>
+struct __iterator_traits_member_reference<_Ip> {
+ using type = typename _Ip::reference;
+};
+
+// [iterator.traits]/3.2.3.4
+// input_iterator_tag
+template <class _Ip>
+struct __deduce_iterator_category {
+ using type = input_iterator_tag;
+};
+
+// [iterator.traits]/3.2.3.1
+// `random_access_iterator_tag` if `I` satisfies `cpp17-random-access-iterator`, or otherwise
+template <__iterator_traits_detail::__cpp17_random_access_iterator _Ip>
+struct __deduce_iterator_category<_Ip> {
+ using type = random_access_iterator_tag;
+};
+
+// [iterator.traits]/3.2.3.2
+// `bidirectional_iterator_tag` if `I` satisfies `cpp17-bidirectional-iterator`, or otherwise
+template <__iterator_traits_detail::__cpp17_bidirectional_iterator _Ip>
+struct __deduce_iterator_category<_Ip> {
+ using type = bidirectional_iterator_tag;
+};
+
+// [iterator.traits]/3.2.3.3
+// `forward_iterator_tag` if `I` satisfies `cpp17-forward-iterator`, or otherwise
+template <__iterator_traits_detail::__cpp17_forward_iterator _Ip>
+struct __deduce_iterator_category<_Ip> {
+ using type = forward_iterator_tag;
+};
+
+template <class _Ip>
+struct __iterator_traits_iterator_category : __deduce_iterator_category<_Ip> {};
+
+// [iterator.traits]/3.2.3
+// If the qualified-id `I::iterator-category` is valid and denotes a type, `iterator-category` names
+// that type.
+template <__has_member_iterator_category _Ip>
+struct __iterator_traits_iterator_category<_Ip> {
+ using type = typename _Ip::iterator_category;
+};
+
+// otherwise, it names void.
+template <class>
+struct __iterator_traits_difference_type {
+ using type = void;
+};
+
+// If the qualified-id `incrementable_traits<I>::difference_type` is valid and denotes a type, then
+// `difference_type` names that type;
+template <class _Ip>
+ requires requires { typename incrementable_traits<_Ip>::difference_type; }
+struct __iterator_traits_difference_type<_Ip> {
+ using type = typename incrementable_traits<_Ip>::difference_type;
+};
+
+// [iterator.traits]/3.4
+// Otherwise, `iterator_traits<I>` has no members by any of the above names.
+template <class>
+struct __iterator_traits {};
+
+// [iterator.traits]/3.1
+// If `I` has valid ([temp.deduct]) member types `difference-type`, `value-type`, `reference`, and
+// `iterator-category`, then `iterator-traits<I>` has the following publicly accessible members:
+template <__specifies_members _Ip>
+struct __iterator_traits<_Ip> {
+ using iterator_category = typename _Ip::iterator_category;
+ using value_type = typename _Ip::value_type;
+ using difference_type = typename _Ip::difference_type;
+ using pointer = typename __iterator_traits_member_pointer_or_void<_Ip>::type;
+ using reference = typename _Ip::reference;
+};
+
+// [iterator.traits]/3.2
+// Otherwise, if `I` satisfies the exposition-only concept `cpp17-input-iterator`,
+// `iterator-traits<I>` has the following publicly accessible members:
+template <__cpp17_input_iterator_missing_members _Ip>
+struct __iterator_traits<_Ip> {
+ using iterator_category = typename __iterator_traits_iterator_category<_Ip>::type;
+ using value_type = typename indirectly_readable_traits<_Ip>::value_type;
+ using difference_type = typename incrementable_traits<_Ip>::difference_type;
+ using pointer = typename __iterator_traits_member_pointer_or_arrow_or_void<_Ip>::type;
+ using reference = typename __iterator_traits_member_reference<_Ip>::type;
+};
+
+// Otherwise, if `I` satisfies the exposition-only concept `cpp17-iterator`, then
+// `iterator_traits<I>` has the following publicly accessible members:
+template <__cpp17_iterator_missing_members _Ip>
+struct __iterator_traits<_Ip> {
+ using iterator_category = output_iterator_tag;
+ using value_type = void;
+ using difference_type = typename __iterator_traits_difference_type<_Ip>::type;
+ using pointer = void;
+ using reference = void;
+};
+
+template <class _Ip>
+struct iterator_traits : __iterator_traits<_Ip> {
+ using __primary_template = iterator_traits;
+};
+
+#else // _LIBCPP_STD_VER >= 20
+
+template <class _Iter, bool>
+struct __iterator_traits {};
+
+template <class _Iter, bool>
+struct __iterator_traits_impl {};
+
+template <class _Iter>
+struct __iterator_traits_impl<_Iter, true> {
+ typedef typename _Iter::difference_type difference_type;
+ typedef typename _Iter::value_type value_type;
+ typedef typename _Iter::pointer pointer;
+ typedef typename _Iter::reference reference;
+ typedef typename _Iter::iterator_category iterator_category;
+};
+
+template <class _Iter>
+struct __iterator_traits<_Iter, true>
+ : __iterator_traits_impl< _Iter,
+ is_convertible<typename _Iter::iterator_category, input_iterator_tag>::value ||
+ is_convertible<typename _Iter::iterator_category, output_iterator_tag>::value > {};
+
+// iterator_traits<Iterator> will only have the nested types if Iterator::iterator_category
+// exists. Else iterator_traits<Iterator> will be an empty class. This is a
+// conforming extension which allows some programs to compile and behave as
+// the client expects instead of failing at compile time.
+
+template <class _Iter>
+struct _LIBCPP_TEMPLATE_VIS iterator_traits : __iterator_traits<_Iter, __has_iterator_typedefs<_Iter>::value> {
+ using __primary_template = iterator_traits;
+};
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+#if _LIBCPP_STD_VER >= 20
+ requires is_object_v<_Tp>
+#endif
+struct _LIBCPP_TEMPLATE_VIS iterator_traits<_Tp*> {
+ typedef ptrdiff_t difference_type;
+ typedef __remove_cv_t<_Tp> value_type;
+ typedef _Tp* pointer;
+ typedef _Tp& reference;
+ typedef random_access_iterator_tag iterator_category;
+#if _LIBCPP_STD_VER >= 20
+ typedef contiguous_iterator_tag iterator_concept;
+#endif
+};
+
+template <class _Tp, class _Up, bool = __has_iterator_category<iterator_traits<_Tp> >::value>
+struct __has_iterator_category_convertible_to : is_convertible<typename iterator_traits<_Tp>::iterator_category, _Up> {
+};
+
+template <class _Tp, class _Up>
+struct __has_iterator_category_convertible_to<_Tp, _Up, false> : false_type {};
+
+template <class _Tp, class _Up, bool = __has_iterator_concept<_Tp>::value>
+struct __has_iterator_concept_convertible_to : is_convertible<typename _Tp::iterator_concept, _Up> {};
+
+template <class _Tp, class _Up>
+struct __has_iterator_concept_convertible_to<_Tp, _Up, false> : false_type {};
+
+template <class _Tp>
+using __has_input_iterator_category = __has_iterator_category_convertible_to<_Tp, input_iterator_tag>;
+
+template <class _Tp>
+using __has_forward_iterator_category = __has_iterator_category_convertible_to<_Tp, forward_iterator_tag>;
+
+template <class _Tp>
+using __has_bidirectional_iterator_category = __has_iterator_category_convertible_to<_Tp, bidirectional_iterator_tag>;
+
+template <class _Tp>
+using __has_random_access_iterator_category = __has_iterator_category_convertible_to<_Tp, random_access_iterator_tag>;
+
+// __libcpp_is_contiguous_iterator determines if an iterator is known by
+// libc++ to be contiguous, either because it advertises itself as such
+// (in C++20) or because it is a pointer type or a known trivial wrapper
+// around a (possibly fancy) pointer type, such as __wrap_iter<T*>.
+// Such iterators receive special "contiguous" optimizations in
+// std::copy and std::sort.
+//
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+struct __libcpp_is_contiguous_iterator
+ : _Or< __has_iterator_category_convertible_to<_Tp, contiguous_iterator_tag>,
+ __has_iterator_concept_convertible_to<_Tp, contiguous_iterator_tag> > {};
+#else
+template <class _Tp>
+struct __libcpp_is_contiguous_iterator : false_type {};
+#endif
+
+// Any native pointer which is an iterator is also a contiguous iterator.
+template <class _Up>
+struct __libcpp_is_contiguous_iterator<_Up*> : true_type {};
+
+template <class _Iter>
+class __wrap_iter;
+
+template <class _Tp>
+using __has_exactly_input_iterator_category =
+ integral_constant<bool,
+ __has_iterator_category_convertible_to<_Tp, input_iterator_tag>::value &&
+ !__has_iterator_category_convertible_to<_Tp, forward_iterator_tag>::value>;
+
+template <class _Tp>
+using __has_exactly_forward_iterator_category =
+ integral_constant<bool,
+ __has_iterator_category_convertible_to<_Tp, forward_iterator_tag>::value &&
+ !__has_iterator_category_convertible_to<_Tp, bidirectional_iterator_tag>::value>;
+
+template <class _Tp>
+using __has_exactly_bidirectional_iterator_category =
+ integral_constant<bool,
+ __has_iterator_category_convertible_to<_Tp, bidirectional_iterator_tag>::value &&
+ !__has_iterator_category_convertible_to<_Tp, random_access_iterator_tag>::value>;
+
+template <class _InputIterator>
+using __iter_value_type = typename iterator_traits<_InputIterator>::value_type;
+
+template <class _InputIterator>
+using __iter_key_type = __remove_const_t<typename iterator_traits<_InputIterator>::value_type::first_type>;
+
+template <class _InputIterator>
+using __iter_mapped_type = typename iterator_traits<_InputIterator>::value_type::second_type;
+
+template <class _InputIterator>
+using __iter_to_alloc_type =
+ pair<const typename iterator_traits<_InputIterator>::value_type::first_type,
+ typename iterator_traits<_InputIterator>::value_type::second_type>;
+
+template <class _Iter>
+using __iterator_category_type = typename iterator_traits<_Iter>::iterator_category;
+
+template <class _Iter>
+using __iterator_pointer_type = typename iterator_traits<_Iter>::pointer;
+
+template <class _Iter>
+using __iter_diff_t = typename iterator_traits<_Iter>::difference_type;
+
+template <class _Iter>
+using __iter_reference = typename iterator_traits<_Iter>::reference;
+
+#if _LIBCPP_STD_VER >= 20
+
+// [readable.traits]
+
+// Let `RI` be `remove_cvref_t<I>`. The type `iter_value_t<I>` denotes
+// `indirectly_readable_traits<RI>::value_type` if `iterator_traits<RI>` names a specialization
+// generated from the primary template, and `iterator_traits<RI>::value_type` otherwise.
+// This has to be in this file and not readable_traits.h to break the include cycle between the two.
+template <class _Ip>
+using iter_value_t =
+ typename conditional_t<__is_primary_template<iterator_traits<remove_cvref_t<_Ip> > >::value,
+ indirectly_readable_traits<remove_cvref_t<_Ip> >,
+ iterator_traits<remove_cvref_t<_Ip> > >::value_type;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_ITERATOR_TRAITS_H
diff --git a/libcxx/include/__cxx03/__iterator/iterator_with_data.h b/libcxx/include/__cxx03/__iterator/iterator_with_data.h
new file mode 100644
index 00000000000000..afdc0a4e12e21c
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/iterator_with_data.h
@@ -0,0 +1,105 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_ITERATOR_WITH_DATA_H
+#define _LIBCPP___ITERATOR_ITERATOR_WITH_DATA_H
+
+#include <__compare/compare_three_way_result.h>
+#include <__compare/three_way_comparable.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <forward_iterator _Iterator, class _Data>
+class __iterator_with_data {
+ _Iterator __iter_{};
+ _Data __data_{};
+
+public:
+ using value_type = iter_value_t<_Iterator>;
+ using difference_type = iter_difference_t<_Iterator>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator_with_data() = default;
+
+ constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data(_Iterator __iter, _Data __data)
+ : __iter_(std::move(__iter)), __data_(std::move(__data)) {}
+
+ constexpr _LIBCPP_HIDE_FROM_ABI _Iterator __get_iter() const { return __iter_; }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI _Data __get_data() && { return std::move(__data_); }
+
+ friend constexpr _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const __iterator_with_data& __lhs, const __iterator_with_data& __rhs) {
+ return __lhs.__iter_ == __rhs.__iter_;
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data& operator++() {
+ ++__iter_;
+ return *this;
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data operator++(int) {
+ auto __tmp = *this;
+ __iter_++;
+ return __tmp;
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data& operator--()
+ requires bidirectional_iterator<_Iterator>
+ {
+ --__iter_;
+ return *this;
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data operator--(int)
+ requires bidirectional_iterator<_Iterator>
+ {
+ auto __tmp = *this;
+ --__iter_;
+ return __tmp;
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI iter_reference_t<_Iterator> operator*() const { return *__iter_; }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_rvalue_reference_t<_Iterator>
+ iter_move(const __iterator_with_data& __iter) noexcept(noexcept(ranges::iter_move(__iter.__iter_))) {
+ return ranges::iter_move(__iter.__iter_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void
+ iter_swap(const __iterator_with_data& __lhs,
+ const __iterator_with_data& __rhs) noexcept(noexcept(ranges::iter_swap(__lhs.__iter_, __rhs.__iter_)))
+ requires indirectly_swappable<_Iterator>
+ {
+ return ranges::iter_swap(__lhs.__data_, __rhs.__iter_);
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_ITERATOR_WITH_DATA_H
diff --git a/libcxx/include/__cxx03/__iterator/mergeable.h b/libcxx/include/__cxx03/__iterator/mergeable.h
new file mode 100644
index 00000000000000..7976d751095e58
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/mergeable.h
@@ -0,0 +1,42 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_MERGEABLE_H
+#define _LIBCPP___ITERATOR_MERGEABLE_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Input1,
+ class _Input2,
+ class _Output,
+ class _Comp = ranges::less,
+ class _Proj1 = identity,
+ class _Proj2 = identity>
+concept mergeable =
+ input_iterator<_Input1> && input_iterator<_Input2> && weakly_incrementable<_Output> &&
+ indirectly_copyable<_Input1, _Output> && indirectly_copyable<_Input2, _Output> &&
+ indirect_strict_weak_order<_Comp, projected<_Input1, _Proj1>, projected<_Input2, _Proj2>>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_MERGEABLE_H
diff --git a/libcxx/include/__cxx03/__iterator/move_iterator.h b/libcxx/include/__cxx03/__iterator/move_iterator.h
new file mode 100644
index 00000000000000..a1c53e9bd2b596
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/move_iterator.h
@@ -0,0 +1,347 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_MOVE_ITERATOR_H
+#define _LIBCPP___ITERATOR_MOVE_ITERATOR_H
+
+#include <__compare/compare_three_way_result.h>
+#include <__compare/three_way_comparable.h>
+#include <__concepts/assignable.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/move_sentinel.h>
+#include <__iterator/readable_traits.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter, class = void>
+struct __move_iter_category_base {};
+
+template <class _Iter>
+ requires requires { typename iterator_traits<_Iter>::iterator_category; }
+struct __move_iter_category_base<_Iter> {
+ using iterator_category =
+ _If< derived_from<typename iterator_traits<_Iter>::iterator_category, random_access_iterator_tag>,
+ random_access_iterator_tag,
+ typename iterator_traits<_Iter>::iterator_category >;
+};
+
+template <class _Iter, class _Sent>
+concept __move_iter_comparable = requires {
+ { std::declval<const _Iter&>() == std::declval<_Sent>() } -> convertible_to<bool>;
+};
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Iter>
+class _LIBCPP_TEMPLATE_VIS move_iterator
+#if _LIBCPP_STD_VER >= 20
+ : public __move_iter_category_base<_Iter>
+#endif
+{
+#if _LIBCPP_STD_VER >= 20
+
+private:
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __get_iter_concept() {
+ if constexpr (random_access_iterator<_Iter>) {
+ return random_access_iterator_tag{};
+ } else if constexpr (bidirectional_iterator<_Iter>) {
+ return bidirectional_iterator_tag{};
+ } else if constexpr (forward_iterator<_Iter>) {
+ return forward_iterator_tag{};
+ } else {
+ return input_iterator_tag{};
+ }
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+public:
+#if _LIBCPP_STD_VER >= 20
+ using iterator_type = _Iter;
+ using iterator_concept = decltype(__get_iter_concept());
+ // iterator_category is inherited and not always present
+ using value_type = iter_value_t<_Iter>;
+ using difference_type = iter_difference_t<_Iter>;
+ using pointer = _Iter;
+ using reference = iter_rvalue_reference_t<_Iter>;
+#else
+ typedef _Iter iterator_type;
+ typedef _If< __has_random_access_iterator_category<_Iter>::value,
+ random_access_iterator_tag,
+ typename iterator_traits<_Iter>::iterator_category >
+ iterator_category;
+ typedef typename iterator_traits<iterator_type>::value_type value_type;
+ typedef typename iterator_traits<iterator_type>::difference_type difference_type;
+ typedef iterator_type pointer;
+
+ typedef typename iterator_traits<iterator_type>::reference __reference;
+ typedef __conditional_t<is_reference<__reference>::value, __libcpp_remove_reference_t<__reference>&&, __reference>
+ reference;
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 explicit move_iterator(_Iter __i) : __current_(std::move(__i)) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator& operator++() {
+ ++__current_;
+ return *this;
+ }
+
+ _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 pointer operator->() const {
+ return __current_;
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr move_iterator()
+ requires is_constructible_v<_Iter>
+ : __current_() {}
+
+ template <class _Up>
+ requires(!_IsSame<_Up, _Iter>::value) && convertible_to<const _Up&, _Iter>
+ _LIBCPP_HIDE_FROM_ABI constexpr move_iterator(const move_iterator<_Up>& __u) : __current_(__u.base()) {}
+
+ template <class _Up>
+ requires(!_IsSame<_Up, _Iter>::value) && convertible_to<const _Up&, _Iter> && assignable_from<_Iter&, const _Up&>
+ _LIBCPP_HIDE_FROM_ABI constexpr move_iterator& operator=(const move_iterator<_Up>& __u) {
+ __current_ = __u.base();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Iter& base() const& noexcept { return __current_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter base() && { return std::move(__current_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference operator*() const { return ranges::iter_move(__current_); }
+ _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](difference_type __n) const {
+ return ranges::iter_move(__current_ + __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator++(int)
+ requires forward_iterator<_Iter>
+ {
+ move_iterator __tmp(*this);
+ ++__current_;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator++(int) { ++__current_; }
+#else
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator() : __current_() {}
+
+ template <class _Up, __enable_if_t< !is_same<_Up, _Iter>::value && is_convertible<const _Up&, _Iter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator(const move_iterator<_Up>& __u)
+ : __current_(__u.base()) {}
+
+ template <class _Up,
+ __enable_if_t< !is_same<_Up, _Iter>::value && is_convertible<const _Up&, _Iter>::value &&
+ is_assignable<_Iter&, const _Up&>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator& operator=(const move_iterator<_Up>& __u) {
+ __current_ = __u.base();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 _Iter base() const { return __current_; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator*() const {
+ return static_cast<reference>(*__current_);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](difference_type __n) const {
+ return static_cast<reference>(__current_[__n]);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator operator++(int) {
+ move_iterator __tmp(*this);
+ ++__current_;
+ return __tmp;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator& operator--() {
+ --__current_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator operator--(int) {
+ move_iterator __tmp(*this);
+ --__current_;
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator operator+(difference_type __n) const {
+ return move_iterator(__current_ + __n);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator& operator+=(difference_type __n) {
+ __current_ += __n;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator operator-(difference_type __n) const {
+ return move_iterator(__current_ - __n);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator& operator-=(difference_type __n) {
+ __current_ -= __n;
+ return *this;
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ template <sentinel_for<_Iter> _Sent>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr bool operator==(const move_iterator& __x, const move_sentinel<_Sent>& __y)
+ requires __move_iter_comparable<_Iter, _Sent>
+ {
+ return __x.base() == __y.base();
+ }
+
+ template <sized_sentinel_for<_Iter> _Sent>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter>
+ operator-(const move_sentinel<_Sent>& __x, const move_iterator& __y) {
+ return __x.base() - __y.base();
+ }
+
+ template <sized_sentinel_for<_Iter> _Sent>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter>
+ operator-(const move_iterator& __x, const move_sentinel<_Sent>& __y) {
+ return __x.base() - __y.base();
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI constexpr iter_rvalue_reference_t<_Iter>
+ iter_move(const move_iterator& __i) noexcept(noexcept(ranges::iter_move(__i.__current_))) {
+ return ranges::iter_move(__i.__current_);
+ }
+
+ template <indirectly_swappable<_Iter> _It2>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr void
+ iter_swap(const move_iterator& __x,
+ const move_iterator<_It2>& __y) noexcept(noexcept(ranges::iter_swap(__x.__current_, __y.__current_))) {
+ return ranges::iter_swap(__x.__current_, __y.__current_);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+private:
+ template <class _It2>
+ friend class move_iterator;
+
+ _Iter __current_;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(move_iterator);
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator==(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y) {
+ return __x.base() == __y.base();
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator!=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y) {
+ return __x.base() != __y.base();
+}
+#endif // _LIBCPP_STD_VER <= 17
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator<(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y) {
+ return __x.base() < __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator>(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y) {
+ return __x.base() > __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator<=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y) {
+ return __x.base() <= __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator>=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y) {
+ return __x.base() >= __y.base();
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter1, three_way_comparable_with<_Iter1> _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr auto
+operator<=>(const move_iterator<_Iter1>& __x,
+ const move_iterator<_Iter2>& __y) -> compare_three_way_result_t<_Iter1, _Iter2> {
+ return __x.base() <=> __y.base();
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto
+operator-(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y) -> decltype(__x.base() - __y.base()) {
+ return __x.base() - __y.base();
+}
+#else
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI typename move_iterator<_Iter1>::difference_type
+operator-(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y) {
+ return __x.base() - __y.base();
+}
+#endif // !_LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter>
+inline _LIBCPP_HIDE_FROM_ABI constexpr move_iterator<_Iter>
+operator+(iter_difference_t<_Iter> __n, const move_iterator<_Iter>& __x)
+ requires requires {
+ { __x.base() + __n } -> same_as<_Iter>;
+ }
+{
+ return __x + __n;
+}
+#else
+template <class _Iter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator<_Iter>
+operator+(typename move_iterator<_Iter>::difference_type __n, const move_iterator<_Iter>& __x) {
+ return move_iterator<_Iter>(__x.base() + __n);
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter1, class _Iter2>
+ requires(!sized_sentinel_for<_Iter1, _Iter2>)
+inline constexpr bool disable_sized_sentinel_for<move_iterator<_Iter1>, move_iterator<_Iter2>> = true;
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Iter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 move_iterator<_Iter> make_move_iterator(_Iter __i) {
+ return move_iterator<_Iter>(std::move(__i));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_MOVE_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/move_sentinel.h b/libcxx/include/__cxx03/__iterator/move_sentinel.h
new file mode 100644
index 00000000000000..4a2a09ef0611d2
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/move_sentinel.h
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_MOVE_SENTINEL_H
+#define _LIBCPP___ITERATOR_MOVE_SENTINEL_H
+
+#include <__concepts/assignable.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/semiregular.h>
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <semiregular _Sent>
+class _LIBCPP_TEMPLATE_VIS move_sentinel {
+public:
+ _LIBCPP_HIDE_FROM_ABI move_sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit move_sentinel(_Sent __s) : __last_(std::move(__s)) {}
+
+ template <class _S2>
+ requires convertible_to<const _S2&, _Sent>
+ _LIBCPP_HIDE_FROM_ABI constexpr move_sentinel(const move_sentinel<_S2>& __s) : __last_(__s.base()) {}
+
+ template <class _S2>
+ requires assignable_from<_Sent&, const _S2&>
+ _LIBCPP_HIDE_FROM_ABI constexpr move_sentinel& operator=(const move_sentinel<_S2>& __s) {
+ __last_ = __s.base();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Sent base() const { return __last_; }
+
+private:
+ _Sent __last_ = _Sent();
+};
+
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(move_sentinel);
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_MOVE_SENTINEL_H
diff --git a/libcxx/include/__cxx03/__iterator/next.h b/libcxx/include/__cxx03/__iterator/next.h
new file mode 100644
index 00000000000000..21d3688ad9eb60
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/next.h
@@ -0,0 +1,83 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_NEXT_H
+#define _LIBCPP___ITERATOR_NEXT_H
+
+#include <__assert>
+#include <__config>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/enable_if.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 _InputIter
+next(_InputIter __x, typename iterator_traits<_InputIter>::difference_type __n = 1) {
+ // Calling `advance` with a negative value on a non-bidirectional iterator is a no-op in the current implementation.
+ // Note that this check duplicates the similar check in `std::advance`.
+ _LIBCPP_ASSERT_PEDANTIC(__n >= 0 || __has_bidirectional_iterator_category<_InputIter>::value,
+ "Attempt to next(it, n) with negative n on a non-bidirectional iterator");
+
+ std::advance(__x, __n);
+ return __x;
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+// [range.iter.op.next]
+
+namespace ranges {
+namespace __next {
+
+struct __fn {
+ template <input_or_output_iterator _Ip>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x) const {
+ ++__x;
+ return __x;
+ }
+
+ template <input_or_output_iterator _Ip>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n) const {
+ ranges::advance(__x, __n);
+ return __x;
+ }
+
+ template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x, _Sp __bound_sentinel) const {
+ ranges::advance(__x, __bound_sentinel);
+ return __x;
+ }
+
+ template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n, _Sp __bound_sentinel) const {
+ ranges::advance(__x, __n, __bound_sentinel);
+ return __x;
+ }
+};
+
+} // namespace __next
+
+inline namespace __cpo {
+inline constexpr auto next = __next::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_NEXT_H
diff --git a/libcxx/include/__cxx03/__iterator/ostream_iterator.h b/libcxx/include/__cxx03/__iterator/ostream_iterator.h
new file mode 100644
index 00000000000000..05697e62d9dcb9
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/ostream_iterator.h
@@ -0,0 +1,75 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_OSTREAM_ITERATOR_H
+#define _LIBCPP___ITERATOR_OSTREAM_ITERATOR_H
+
+#include <__config>
+#include <__fwd/ostream.h>
+#include <__fwd/string.h>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Tp, class _CharT = char, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS ostream_iterator
+#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<output_iterator_tag, void, void, void, void>
+#endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+#if _LIBCPP_STD_VER >= 20
+ typedef ptrdiff_t difference_type;
+#else
+ typedef void difference_type;
+#endif
+ typedef void pointer;
+ typedef void reference;
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef basic_ostream<_CharT, _Traits> ostream_type;
+
+private:
+ ostream_type* __out_stream_;
+ const char_type* __delim_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI ostream_iterator(ostream_type& __s) _NOEXCEPT
+ : __out_stream_(std::addressof(__s)),
+ __delim_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI ostream_iterator(ostream_type& __s, const _CharT* __delimiter) _NOEXCEPT
+ : __out_stream_(std::addressof(__s)),
+ __delim_(__delimiter) {}
+ _LIBCPP_HIDE_FROM_ABI ostream_iterator& operator=(const _Tp& __value) {
+ *__out_stream_ << __value;
+ if (__delim_)
+ *__out_stream_ << __delim_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ostream_iterator& operator*() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI ostream_iterator& operator++() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI ostream_iterator& operator++(int) { return *this; }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_OSTREAM_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/ostreambuf_iterator.h b/libcxx/include/__cxx03/__iterator/ostreambuf_iterator.h
new file mode 100644
index 00000000000000..dda0094dc3f535
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/ostreambuf_iterator.h
@@ -0,0 +1,72 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_OSTREAMBUF_ITERATOR_H
+#define _LIBCPP___ITERATOR_OSTREAMBUF_ITERATOR_H
+
+#include <__config>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <cstddef>
+#include <iosfwd> // for forward declaration of basic_streambuf
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS ostreambuf_iterator
+#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<output_iterator_tag, void, void, void, void>
+#endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+#if _LIBCPP_STD_VER >= 20
+ typedef ptrdiff_t difference_type;
+#else
+ typedef void difference_type;
+#endif
+ typedef void pointer;
+ typedef void reference;
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef basic_streambuf<_CharT, _Traits> streambuf_type;
+ typedef basic_ostream<_CharT, _Traits> ostream_type;
+
+private:
+ streambuf_type* __sbuf_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI ostreambuf_iterator(ostream_type& __s) _NOEXCEPT : __sbuf_(__s.rdbuf()) {}
+ _LIBCPP_HIDE_FROM_ABI ostreambuf_iterator(streambuf_type* __s) _NOEXCEPT : __sbuf_(__s) {}
+ _LIBCPP_HIDE_FROM_ABI ostreambuf_iterator& operator=(_CharT __c) {
+ if (__sbuf_ && traits_type::eq_int_type(__sbuf_->sputc(__c), traits_type::eof()))
+ __sbuf_ = nullptr;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI ostreambuf_iterator& operator*() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI ostreambuf_iterator& operator++() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI ostreambuf_iterator& operator++(int) { return *this; }
+ _LIBCPP_HIDE_FROM_ABI bool failed() const _NOEXCEPT { return __sbuf_ == nullptr; }
+
+ template <class _Ch, class _Tr>
+ friend _LIBCPP_HIDE_FROM_ABI ostreambuf_iterator<_Ch, _Tr> __pad_and_output(
+ ostreambuf_iterator<_Ch, _Tr> __s, const _Ch* __ob, const _Ch* __op, const _Ch* __oe, ios_base& __iob, _Ch __fl);
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_OSTREAMBUF_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/permutable.h b/libcxx/include/__cxx03/__iterator/permutable.h
new file mode 100644
index 00000000000000..f65ba3bfbbaad4
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/permutable.h
@@ -0,0 +1,34 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_PERMUTABLE_H
+#define _LIBCPP___ITERATOR_PERMUTABLE_H
+
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iter_swap.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Iterator>
+concept permutable =
+ forward_iterator<_Iterator> && indirectly_movable_storable<_Iterator, _Iterator> &&
+ indirectly_swappable<_Iterator, _Iterator>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_PERMUTABLE_H
diff --git a/libcxx/include/__cxx03/__iterator/prev.h b/libcxx/include/__cxx03/__iterator/prev.h
new file mode 100644
index 00000000000000..2f0e6a088edb36
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/prev.h
@@ -0,0 +1,76 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_PREV_H
+#define _LIBCPP___ITERATOR_PREV_H
+
+#include <__assert>
+#include <__config>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/enable_if.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 _InputIter
+prev(_InputIter __x, typename iterator_traits<_InputIter>::difference_type __n = 1) {
+ // Calling `advance` with a negative value on a non-bidirectional iterator is a no-op in the current implementation.
+ // Note that this check duplicates the similar check in `std::advance`.
+ _LIBCPP_ASSERT_PEDANTIC(__n <= 0 || __has_bidirectional_iterator_category<_InputIter>::value,
+ "Attempt to prev(it, n) with a positive n on a non-bidirectional iterator");
+ std::advance(__x, -__n);
+ return __x;
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+// [range.iter.op.prev]
+
+namespace ranges {
+namespace __prev {
+
+struct __fn {
+ template <bidirectional_iterator _Ip>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x) const {
+ --__x;
+ return __x;
+ }
+
+ template <bidirectional_iterator _Ip>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n) const {
+ ranges::advance(__x, -__n);
+ return __x;
+ }
+
+ template <bidirectional_iterator _Ip>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n, _Ip __bound_iter) const {
+ ranges::advance(__x, -__n, __bound_iter);
+ return __x;
+ }
+};
+
+} // namespace __prev
+
+inline namespace __cpo {
+inline constexpr auto prev = __prev::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_PREV_H
diff --git a/libcxx/include/__cxx03/__iterator/projected.h b/libcxx/include/__cxx03/__iterator/projected.h
new file mode 100644
index 00000000000000..463d07b0d33c2d
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/projected.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_PROJECTED_H
+#define _LIBCPP___ITERATOR_PROJECTED_H
+
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h> // iter_difference_t
+#include <__type_traits/remove_cvref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _It, class _Proj>
+struct __projected_impl {
+ struct __type {
+ using value_type = remove_cvref_t<indirect_result_t<_Proj&, _It>>;
+ indirect_result_t<_Proj&, _It> operator*() const; // not defined
+ };
+};
+
+template <weakly_incrementable _It, class _Proj>
+struct __projected_impl<_It, _Proj> {
+ struct __type {
+ using value_type = remove_cvref_t<indirect_result_t<_Proj&, _It>>;
+ using difference_type = iter_difference_t<_It>;
+ indirect_result_t<_Proj&, _It> operator*() const; // not defined
+ };
+};
+
+// Note that we implement std::projected in a way that satisfies P2538R1 even in standard
+// modes before C++26 to avoid breaking the ABI between standard modes (even though ABI
+// breaks with std::projected are expected to have essentially no impact).
+template <indirectly_readable _It, indirectly_regular_unary_invocable<_It> _Proj>
+using projected = typename __projected_impl<_It, _Proj>::__type;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_PROJECTED_H
diff --git a/libcxx/include/__cxx03/__iterator/ranges_iterator_traits.h b/libcxx/include/__cxx03/__iterator/ranges_iterator_traits.h
new file mode 100644
index 00000000000000..859e7082048ac1
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/ranges_iterator_traits.h
@@ -0,0 +1,40 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_RANGES_ITERATOR_TRAITS_H
+#define _LIBCPP___ITERATOR_RANGES_ITERATOR_TRAITS_H
+
+#include <__config>
+#include <__fwd/pair.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/remove_const.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <ranges::input_range _Range>
+using __range_key_type = __remove_const_t<typename ranges::range_value_t<_Range>::first_type>;
+
+template <ranges::input_range _Range>
+using __range_mapped_type = typename ranges::range_value_t<_Range>::second_type;
+
+template <ranges::input_range _Range>
+using __range_to_alloc_type =
+ pair<const typename ranges::range_value_t<_Range>::first_type, typename ranges::range_value_t<_Range>::second_type>;
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_RANGES_ITERATOR_TRAITS_H
diff --git a/libcxx/include/__cxx03/__iterator/readable_traits.h b/libcxx/include/__cxx03/__iterator/readable_traits.h
new file mode 100644
index 00000000000000..25e74567fff11d
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/readable_traits.h
@@ -0,0 +1,81 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_READABLE_TRAITS_H
+#define _LIBCPP___ITERATOR_READABLE_TRAITS_H
+
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_primary_template.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_extent.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [readable.traits]
+template <class>
+struct __cond_value_type {};
+
+template <class _Tp>
+ requires is_object_v<_Tp>
+struct __cond_value_type<_Tp> {
+ using value_type = remove_cv_t<_Tp>;
+};
+
+template <class _Tp>
+concept __has_member_value_type = requires { typename _Tp::value_type; };
+
+template <class _Tp>
+concept __has_member_element_type = requires { typename _Tp::element_type; };
+
+template <class>
+struct indirectly_readable_traits {};
+
+template <class _Ip>
+ requires is_array_v<_Ip>
+struct indirectly_readable_traits<_Ip> {
+ using value_type = remove_cv_t<remove_extent_t<_Ip>>;
+};
+
+template <class _Ip>
+struct indirectly_readable_traits<const _Ip> : indirectly_readable_traits<_Ip> {};
+
+template <class _Tp>
+struct indirectly_readable_traits<_Tp*> : __cond_value_type<_Tp> {};
+
+template <__has_member_value_type _Tp>
+struct indirectly_readable_traits<_Tp> : __cond_value_type<typename _Tp::value_type> {};
+
+template <__has_member_element_type _Tp>
+struct indirectly_readable_traits<_Tp> : __cond_value_type<typename _Tp::element_type> {};
+
+template <__has_member_value_type _Tp>
+ requires __has_member_element_type<_Tp>
+struct indirectly_readable_traits<_Tp> {};
+
+template <__has_member_value_type _Tp>
+ requires __has_member_element_type<_Tp> &&
+ same_as<remove_cv_t<typename _Tp::element_type>, remove_cv_t<typename _Tp::value_type>>
+struct indirectly_readable_traits<_Tp> : __cond_value_type<typename _Tp::value_type> {};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_READABLE_TRAITS_H
diff --git a/libcxx/include/__cxx03/__iterator/reverse_access.h b/libcxx/include/__cxx03/__iterator/reverse_access.h
new file mode 100644
index 00000000000000..54d7270b04a537
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/reverse_access.h
@@ -0,0 +1,80 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_REVERSE_ACCESS_H
+#define _LIBCPP___ITERATOR_REVERSE_ACCESS_H
+
+#include <__config>
+#include <__iterator/reverse_iterator.h>
+#include <cstddef>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 14
+
+template <class _Tp, size_t _Np>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator<_Tp*> rbegin(_Tp (&__array)[_Np]) {
+ return reverse_iterator<_Tp*>(__array + _Np);
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator<_Tp*> rend(_Tp (&__array)[_Np]) {
+ return reverse_iterator<_Tp*>(__array);
+}
+
+template <class _Ep>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator<const _Ep*> rbegin(initializer_list<_Ep> __il) {
+ return reverse_iterator<const _Ep*>(__il.end());
+}
+
+template <class _Ep>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator<const _Ep*> rend(initializer_list<_Ep> __il) {
+ return reverse_iterator<const _Ep*>(__il.begin());
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto rbegin(_Cp& __c) -> decltype(__c.rbegin()) {
+ return __c.rbegin();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto rbegin(const _Cp& __c) -> decltype(__c.rbegin()) {
+ return __c.rbegin();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto rend(_Cp& __c) -> decltype(__c.rend()) {
+ return __c.rend();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto rend(const _Cp& __c) -> decltype(__c.rend()) {
+ return __c.rend();
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto crbegin(const _Cp& __c) -> decltype(std::rbegin(__c)) {
+ return std::rbegin(__c);
+}
+
+template <class _Cp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto crend(const _Cp& __c) -> decltype(std::rend(__c)) {
+ return std::rend(__c);
+}
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_REVERSE_ACCESS_H
diff --git a/libcxx/include/__cxx03/__iterator/reverse_iterator.h b/libcxx/include/__cxx03/__iterator/reverse_iterator.h
new file mode 100644
index 00000000000000..50c0f21eaa286b
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/reverse_iterator.h
@@ -0,0 +1,346 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
+#define _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
+
+#include <__algorithm/unwrap_iter.h>
+#include <__compare/compare_three_way_result.h>
+#include <__compare/three_way_comparable.h>
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/prev.h>
+#include <__iterator/readable_traits.h>
+#include <__iterator/segmented_iterator.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/subrange.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
+#include <__utility/declval.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Iter>
+class _LIBCPP_TEMPLATE_VIS reverse_iterator
+#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<typename iterator_traits<_Iter>::iterator_category,
+ typename iterator_traits<_Iter>::value_type,
+ typename iterator_traits<_Iter>::difference_type,
+ typename iterator_traits<_Iter>::pointer,
+ typename iterator_traits<_Iter>::reference>
+#endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+private:
+#ifndef _LIBCPP_ABI_NO_ITERATOR_BASES
+ _Iter __t_; // no longer used as of LWG #2360, not removed due to ABI break
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+ static_assert(__has_bidirectional_iterator_category<_Iter>::value || bidirectional_iterator<_Iter>,
+ "reverse_iterator<It> requires It to be a bidirectional iterator.");
+#endif // _LIBCPP_STD_VER >= 20
+
+protected:
+ _Iter current;
+
+public:
+ using iterator_type = _Iter;
+
+ using iterator_category =
+ _If<__has_random_access_iterator_category<_Iter>::value,
+ random_access_iterator_tag,
+ typename iterator_traits<_Iter>::iterator_category>;
+ using pointer = typename iterator_traits<_Iter>::pointer;
+#if _LIBCPP_STD_VER >= 20
+ using iterator_concept = _If<random_access_iterator<_Iter>, random_access_iterator_tag, bidirectional_iterator_tag>;
+ using value_type = iter_value_t<_Iter>;
+ using difference_type = iter_difference_t<_Iter>;
+ using reference = iter_reference_t<_Iter>;
+#else
+ using value_type = typename iterator_traits<_Iter>::value_type;
+ using difference_type = typename iterator_traits<_Iter>::difference_type;
+ using reference = typename iterator_traits<_Iter>::reference;
+#endif
+
+#ifndef _LIBCPP_ABI_NO_ITERATOR_BASES
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator() : __t_(), current() {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 explicit reverse_iterator(_Iter __x) : __t_(__x), current(__x) {}
+
+ template <class _Up, __enable_if_t<!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator(const reverse_iterator<_Up>& __u)
+ : __t_(__u.base()), current(__u.base()) {}
+
+ template <class _Up,
+ __enable_if_t<!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value &&
+ is_assignable<_Iter&, _Up const&>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator=(const reverse_iterator<_Up>& __u) {
+ __t_ = current = __u.base();
+ return *this;
+ }
+#else
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator() : current() {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 explicit reverse_iterator(_Iter __x) : current(__x) {}
+
+ template <class _Up, __enable_if_t<!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator(const reverse_iterator<_Up>& __u)
+ : current(__u.base()) {}
+
+ template <class _Up,
+ __enable_if_t<!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value &&
+ is_assignable<_Iter&, _Up const&>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator=(const reverse_iterator<_Up>& __u) {
+ current = __u.base();
+ return *this;
+ }
+#endif
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 _Iter base() const { return current; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator*() const {
+ _Iter __tmp = current;
+ return *--__tmp;
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr pointer operator->() const
+ requires is_pointer_v<_Iter> || requires(const _Iter __i) { __i.operator->(); }
+ {
+ if constexpr (is_pointer_v<_Iter>) {
+ return std::prev(current);
+ } else {
+ return std::prev(current).operator->();
+ }
+ }
+#else
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 pointer operator->() const { return std::addressof(operator*()); }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator++() {
+ --current;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator operator++(int) {
+ reverse_iterator __tmp(*this);
+ --current;
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator--() {
+ ++current;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator operator--(int) {
+ reverse_iterator __tmp(*this);
+ ++current;
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator operator+(difference_type __n) const {
+ return reverse_iterator(current - __n);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator+=(difference_type __n) {
+ current -= __n;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator operator-(difference_type __n) const {
+ return reverse_iterator(current + __n);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator-=(difference_type __n) {
+ current += __n;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](difference_type __n) const {
+ return *(*this + __n);
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_rvalue_reference_t<_Iter> iter_move(const reverse_iterator& __i) noexcept(
+ is_nothrow_copy_constructible_v<_Iter> && noexcept(ranges::iter_move(--std::declval<_Iter&>()))) {
+ auto __tmp = __i.base();
+ return ranges::iter_move(--__tmp);
+ }
+
+ template <indirectly_swappable<_Iter> _Iter2>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void
+ iter_swap(const reverse_iterator& __x, const reverse_iterator<_Iter2>& __y) noexcept(
+ is_nothrow_copy_constructible_v<_Iter> && is_nothrow_copy_constructible_v<_Iter2> &&
+ noexcept(ranges::iter_swap(--std::declval<_Iter&>(), --std::declval<_Iter2&>()))) {
+ auto __xtmp = __x.base();
+ auto __ytmp = __y.base();
+ ranges::iter_swap(--__xtmp, --__ytmp);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+};
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator==(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
+#if _LIBCPP_STD_VER >= 20
+ requires requires {
+ { __x.base() == __y.base() } -> convertible_to<bool>;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+{
+ return __x.base() == __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator<(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
+#if _LIBCPP_STD_VER >= 20
+ requires requires {
+ { __x.base() > __y.base() } -> convertible_to<bool>;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+{
+ return __x.base() > __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator!=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
+#if _LIBCPP_STD_VER >= 20
+ requires requires {
+ { __x.base() != __y.base() } -> convertible_to<bool>;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+{
+ return __x.base() != __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
+#if _LIBCPP_STD_VER >= 20
+ requires requires {
+ { __x.base() < __y.base() } -> convertible_to<bool>;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+{
+ return __x.base() < __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator>=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
+#if _LIBCPP_STD_VER >= 20
+ requires requires {
+ { __x.base() <= __y.base() } -> convertible_to<bool>;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+{
+ return __x.base() <= __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
+operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
+#if _LIBCPP_STD_VER >= 20
+ requires requires {
+ { __x.base() >= __y.base() } -> convertible_to<bool>;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+{
+ return __x.base() >= __y.base();
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter1, three_way_comparable_with<_Iter1> _Iter2>
+_LIBCPP_HIDE_FROM_ABI constexpr compare_three_way_result_t<_Iter1, _Iter2>
+operator<=>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) {
+ return __y.base() <=> __x.base();
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto
+operator-(const reverse_iterator<_Iter1>& __x,
+ const reverse_iterator<_Iter2>& __y) -> decltype(__y.base() - __x.base()) {
+ return __y.base() - __x.base();
+}
+#else
+template <class _Iter1, class _Iter2>
+inline _LIBCPP_HIDE_FROM_ABI typename reverse_iterator<_Iter1>::difference_type
+operator-(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) {
+ return __y.base() - __x.base();
+}
+#endif
+
+template <class _Iter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator<_Iter>
+operator+(typename reverse_iterator<_Iter>::difference_type __n, const reverse_iterator<_Iter>& __x) {
+ return reverse_iterator<_Iter>(__x.base() - __n);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter1, class _Iter2>
+ requires(!sized_sentinel_for<_Iter1, _Iter2>)
+inline constexpr bool disable_sized_sentinel_for<reverse_iterator<_Iter1>, reverse_iterator<_Iter2>> = true;
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Iter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator<_Iter> make_reverse_iterator(_Iter __i) {
+ return reverse_iterator<_Iter>(__i);
+}
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+template <ranges::bidirectional_range _Range>
+_LIBCPP_HIDE_FROM_ABI constexpr ranges::subrange<reverse_iterator<ranges::iterator_t<_Range>>,
+ reverse_iterator<ranges::iterator_t<_Range>>>
+__reverse_range(_Range&& __range) {
+ auto __first = ranges::begin(__range);
+ return {std::make_reverse_iterator(ranges::next(__first, ranges::end(__range))), std::make_reverse_iterator(__first)};
+}
+#endif
+
+template <class _Iter, bool __b>
+struct __unwrap_iter_impl<reverse_iterator<reverse_iterator<_Iter> >, __b> {
+ using _UnwrappedIter = decltype(__unwrap_iter_impl<_Iter>::__unwrap(std::declval<_Iter>()));
+ using _ReverseWrapper = reverse_iterator<reverse_iterator<_Iter> >;
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ReverseWrapper
+ __rewrap(_ReverseWrapper __orig_iter, _UnwrappedIter __unwrapped_iter) {
+ return _ReverseWrapper(
+ reverse_iterator<_Iter>(__unwrap_iter_impl<_Iter>::__rewrap(__orig_iter.base().base(), __unwrapped_iter)));
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _UnwrappedIter __unwrap(_ReverseWrapper __i) _NOEXCEPT {
+ return __unwrap_iter_impl<_Iter>::__unwrap(__i.base().base());
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/segmented_iterator.h b/libcxx/include/__cxx03/__iterator/segmented_iterator.h
new file mode 100644
index 00000000000000..f3cd1e5fa1f5da
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/segmented_iterator.h
@@ -0,0 +1,79 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SEGMENTED_ITERATOR_H
+#define _LIBCPP___SEGMENTED_ITERATOR_H
+
+// Segmented iterators are iterators over (not necessarily contiguous) sub-ranges.
+//
+// For example, std::deque stores its data into multiple blocks of contiguous memory,
+// which are not stored contiguously themselves. The concept of segmented iterators
+// allows algorithms to operate over these multi-level iterators natively, opening the
+// door to various optimizations. See http://lafstern.org/matt/segmented.pdf for details.
+//
+// If __segmented_iterator_traits can be instantiated, the following functions and associated types must be provided:
+// - Traits::__local_iterator
+// The type of iterators used to iterate inside a segment.
+//
+// - Traits::__segment_iterator
+// The type of iterators used to iterate over segments.
+// Segment iterators can be forward iterators or bidirectional iterators, depending on the
+// underlying data structure.
+//
+// - static __segment_iterator Traits::__segment(It __it)
+// Returns an iterator to the segment that the provided iterator is in.
+//
+// - static __local_iterator Traits::__local(It __it)
+// Returns the local iterator pointing to the element that the provided iterator points to.
+//
+// - static __local_iterator Traits::__begin(__segment_iterator __it)
+// Returns the local iterator to the beginning of the segment that the provided iterator is pointing into.
+//
+// - static __local_iterator Traits::__end(__segment_iterator __it)
+// Returns the one-past-the-end local iterator to the segment that the provided iterator is pointing into.
+//
+// - static It Traits::__compose(__segment_iterator, __local_iterator)
+// Returns the iterator composed of the segment iterator and local iterator.
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Iterator>
+struct __segmented_iterator_traits;
+/* exposition-only:
+{
+ using __segment_iterator = ...;
+ using __local_iterator = ...;
+
+ static __segment_iterator __segment(_Iterator);
+ static __local_iterator __local(_Iterator);
+ static __local_iterator __begin(__segment_iterator);
+ static __local_iterator __end(__segment_iterator);
+ static _Iterator __compose(__segment_iterator, __local_iterator);
+};
+*/
+
+template <class _Tp, size_t = 0>
+struct __has_specialization : false_type {};
+
+template <class _Tp>
+struct __has_specialization<_Tp, sizeof(_Tp) * 0> : true_type {};
+
+template <class _Iterator>
+using __is_segmented_iterator = __has_specialization<__segmented_iterator_traits<_Iterator> >;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___SEGMENTED_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__iterator/size.h b/libcxx/include/__cxx03/__iterator/size.h
new file mode 100644
index 00000000000000..876e6963f77d91
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/size.h
@@ -0,0 +1,59 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_SIZE_H
+#define _LIBCPP___ITERATOR_SIZE_H
+
+#include <__config>
+#include <__type_traits/common_type.h>
+#include <__type_traits/make_signed.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Cont>
+_LIBCPP_HIDE_FROM_ABI constexpr auto size(const _Cont& __c) noexcept(noexcept(__c.size())) -> decltype(__c.size()) {
+ return __c.size();
+}
+
+template <class _Tp, size_t _Sz>
+_LIBCPP_HIDE_FROM_ABI constexpr size_t size(const _Tp (&)[_Sz]) noexcept {
+ return _Sz;
+}
+
+# if _LIBCPP_STD_VER >= 20
+template <class _Cont>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+ssize(const _Cont& __c) noexcept(noexcept(static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(
+ __c.size()))) -> common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>> {
+ return static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size());
+}
+
+// GCC complains about the implicit conversion from ptrdiff_t to size_t in
+// the array bound.
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wsign-conversion")
+template <class _Tp, ptrdiff_t _Sz>
+_LIBCPP_HIDE_FROM_ABI constexpr ptrdiff_t ssize(const _Tp (&)[_Sz]) noexcept {
+ return _Sz;
+}
+_LIBCPP_DIAGNOSTIC_POP
+# endif
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_SIZE_H
diff --git a/libcxx/include/__cxx03/__iterator/sortable.h b/libcxx/include/__cxx03/__iterator/sortable.h
new file mode 100644
index 00000000000000..1444860f2aa105
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/sortable.h
@@ -0,0 +1,35 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_SORTABLE_H
+#define _LIBCPP___ITERATOR_SORTABLE_H
+
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/permutable.h>
+#include <__iterator/projected.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Iter, class _Comp = ranges::less, class _Proj = identity>
+concept sortable = permutable<_Iter> && indirect_strict_weak_order<_Comp, projected<_Iter, _Proj>>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_SORTABLE_H
diff --git a/libcxx/include/__cxx03/__iterator/unreachable_sentinel.h b/libcxx/include/__cxx03/__iterator/unreachable_sentinel.h
new file mode 100644
index 00000000000000..77e663da4b3a6a
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/unreachable_sentinel.h
@@ -0,0 +1,37 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_UNREACHABLE_SENTINEL_H
+#define _LIBCPP___ITERATOR_UNREACHABLE_SENTINEL_H
+
+#include <__config>
+#include <__iterator/concepts.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+struct unreachable_sentinel_t {
+ template <weakly_incrementable _Iter>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(unreachable_sentinel_t, const _Iter&) noexcept {
+ return false;
+ }
+};
+
+inline constexpr unreachable_sentinel_t unreachable_sentinel{};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_UNREACHABLE_SENTINEL_H
diff --git a/libcxx/include/__cxx03/__iterator/wrap_iter.h b/libcxx/include/__cxx03/__iterator/wrap_iter.h
new file mode 100644
index 00000000000000..56183c0ee794d0
--- /dev/null
+++ b/libcxx/include/__cxx03/__iterator/wrap_iter.h
@@ -0,0 +1,244 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ITERATOR_WRAP_ITER_H
+#define _LIBCPP___ITERATOR_WRAP_ITER_H
+
+#include <__compare/ordering.h>
+#include <__compare/three_way_comparable.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_convertible.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Iter>
+class __wrap_iter {
+public:
+ typedef _Iter iterator_type;
+ typedef typename iterator_traits<iterator_type>::value_type value_type;
+ typedef typename iterator_traits<iterator_type>::difference_type difference_type;
+ typedef typename iterator_traits<iterator_type>::pointer pointer;
+ typedef typename iterator_traits<iterator_type>::reference reference;
+ typedef typename iterator_traits<iterator_type>::iterator_category iterator_category;
+#if _LIBCPP_STD_VER >= 20
+ typedef contiguous_iterator_tag iterator_concept;
+#endif
+
+private:
+ iterator_type __i_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter() _NOEXCEPT : __i_() {}
+ template <class _Up, __enable_if_t<is_convertible<_Up, iterator_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter(const __wrap_iter<_Up>& __u) _NOEXCEPT
+ : __i_(__u.base()) {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator*() const _NOEXCEPT { return *__i_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pointer operator->() const _NOEXCEPT {
+ return std::__to_address(__i_);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator++() _NOEXCEPT {
+ ++__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator++(int) _NOEXCEPT {
+ __wrap_iter __tmp(*this);
+ ++(*this);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator--() _NOEXCEPT {
+ --__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator--(int) _NOEXCEPT {
+ __wrap_iter __tmp(*this);
+ --(*this);
+ return __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator+(difference_type __n) const _NOEXCEPT {
+ __wrap_iter __w(*this);
+ __w += __n;
+ return __w;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator+=(difference_type __n) _NOEXCEPT {
+ __i_ += __n;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator-(difference_type __n) const _NOEXCEPT {
+ return *this + (-__n);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator-=(difference_type __n) _NOEXCEPT {
+ *this += -__n;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator[](difference_type __n) const _NOEXCEPT {
+ return __i_[__n];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 iterator_type base() const _NOEXCEPT { return __i_; }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __wrap_iter(iterator_type __x) _NOEXCEPT : __i_(__x) {}
+
+ template <class _Up>
+ friend class __wrap_iter;
+ template <class _CharT, class _Traits, class _Alloc>
+ friend class basic_string;
+ template <class _CharT, class _Traits>
+ friend class basic_string_view;
+ template <class _Tp, class _Alloc>
+ friend class _LIBCPP_TEMPLATE_VIS vector;
+ template <class _Tp, size_t>
+ friend class _LIBCPP_TEMPLATE_VIS span;
+ template <class _Tp, size_t _Size>
+ friend struct array;
+};
+
+template <class _Iter1>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
+ return __x.base() == __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
+ return __x.base() == __y.base();
+}
+
+template <class _Iter1>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
+ return __x.base() < __y.base();
+}
+
+template <class _Iter1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
+ return __x.base() < __y.base();
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _Iter1>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
+ return !(__x == __y);
+}
+
+template <class _Iter1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
+ return !(__x == __y);
+}
+#endif
+
+// TODO(mordante) disable these overloads in the LLVM 20 release.
+template <class _Iter1>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
+ return __y < __x;
+}
+
+template <class _Iter1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
+ return __y < __x;
+}
+
+template <class _Iter1>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
+ return !(__x < __y);
+}
+
+template <class _Iter1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
+ return !(__x < __y);
+}
+
+template <class _Iter1>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
+ return !(__y < __x);
+}
+
+template <class _Iter1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
+operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
+ return !(__y < __x);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Iter1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI constexpr strong_ordering
+operator<=>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) noexcept {
+ if constexpr (three_way_comparable_with<_Iter1, _Iter2, strong_ordering>) {
+ return __x.base() <=> __y.base();
+ } else {
+ if (__x.base() < __y.base())
+ return strong_ordering::less;
+
+ if (__x.base() == __y.base())
+ return strong_ordering::equal;
+
+ return strong_ordering::greater;
+ }
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Iter1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
+#ifndef _LIBCPP_CXX03_LANG
+ auto
+ operator-(const __wrap_iter<_Iter1>& __x,
+ const __wrap_iter<_Iter2>& __y) _NOEXCEPT->decltype(__x.base() - __y.base())
+#else
+typename __wrap_iter<_Iter1>::difference_type
+operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+#endif // C++03
+{
+ return __x.base() - __y.base();
+}
+
+template <class _Iter1>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter<_Iter1>
+operator+(typename __wrap_iter<_Iter1>::difference_type __n, __wrap_iter<_Iter1> __x) _NOEXCEPT {
+ __x += __n;
+ return __x;
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _It>
+struct __libcpp_is_contiguous_iterator<__wrap_iter<_It> > : true_type {};
+#endif
+
+template <class _It>
+struct _LIBCPP_TEMPLATE_VIS pointer_traits<__wrap_iter<_It> > {
+ typedef __wrap_iter<_It> pointer;
+ typedef typename pointer_traits<_It>::element_type element_type;
+ typedef typename pointer_traits<_It>::difference_type difference_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR static element_type* to_address(pointer __w) _NOEXCEPT {
+ return std::__to_address(__w.base());
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ITERATOR_WRAP_ITER_H
diff --git a/libcxx/include/__cxx03/__locale b/libcxx/include/__cxx03/__locale
new file mode 100644
index 00000000000000..4b382764b44645
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale
@@ -0,0 +1,1513 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE
+#define _LIBCPP___LOCALE
+
+#include <__config>
+#include <__locale_dir/locale_base_api.h>
+#include <__memory/shared_ptr.h> // __shared_count
+#include <__mutex/once_flag.h>
+#include <__type_traits/make_unsigned.h>
+#include <__utility/no_destroy.h>
+#include <__utility/private_constructor_tag.h>
+#include <cctype>
+#include <clocale>
+#include <cstdint>
+#include <cstdlib>
+#include <string>
+
+// Some platforms require more includes than others. Keep the includes on all plaforms for now.
+#include <cstddef>
+#include <cstring>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+# include <cwchar>
+#else
+# include <__std_mbstate_t.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_EXPORTED_FROM_ABI locale;
+
+template <class _Facet>
+_LIBCPP_HIDE_FROM_ABI bool has_facet(const locale&) _NOEXCEPT;
+
+template <class _Facet>
+_LIBCPP_HIDE_FROM_ABI const _Facet& use_facet(const locale&);
+
+class _LIBCPP_EXPORTED_FROM_ABI locale {
+public:
+ // locale is essentially a shared_ptr that doesn't support weak_ptrs and never got a move constructor.
+ using __trivially_relocatable = locale;
+
+ // types:
+ class _LIBCPP_EXPORTED_FROM_ABI facet;
+ class _LIBCPP_EXPORTED_FROM_ABI id;
+
+ typedef int category;
+
+ static const category // values assigned here are for exposition only
+ none = 0,
+ collate = LC_COLLATE_MASK, ctype = LC_CTYPE_MASK, monetary = LC_MONETARY_MASK, numeric = LC_NUMERIC_MASK,
+ time = LC_TIME_MASK, messages = LC_MESSAGES_MASK, all = collate | ctype | monetary | numeric | time | messages;
+
+ // construct/copy/destroy:
+ locale() _NOEXCEPT;
+ locale(const locale&) _NOEXCEPT;
+ explicit locale(const char*);
+ explicit locale(const string&);
+ locale(const locale&, const char*, category);
+ locale(const locale&, const string&, category);
+ template <class _Facet>
+ _LIBCPP_HIDE_FROM_ABI locale(const locale&, _Facet*);
+ locale(const locale&, const locale&, category);
+
+ ~locale();
+
+ const locale& operator=(const locale&) _NOEXCEPT;
+
+ template <class _Facet>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS locale combine(const locale&) const;
+
+ // locale operations:
+ string name() const;
+ bool operator==(const locale&) const;
+#if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(const locale& __y) const { return !(*this == __y); }
+#endif
+ template <class _CharT, class _Traits, class _Allocator>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS bool
+ operator()(const basic_string<_CharT, _Traits, _Allocator>&, const basic_string<_CharT, _Traits, _Allocator>&) const;
+
+ // global locale objects:
+ static locale global(const locale&);
+ static const locale& classic();
+
+private:
+ class __imp;
+ __imp* __locale_;
+
+ template <class>
+ friend struct __no_destroy;
+ _LIBCPP_HIDE_FROM_ABI explicit locale(__private_constructor_tag, __imp* __loc) : __locale_(__loc) {}
+
+ void __install_ctor(const locale&, facet*, long);
+ static locale& __global();
+ bool has_facet(id&) const;
+ const facet* use_facet(id&) const;
+
+ template <class _Facet>
+ friend bool has_facet(const locale&) _NOEXCEPT;
+ template <class _Facet>
+ friend const _Facet& use_facet(const locale&);
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI locale::facet : public __shared_count {
+protected:
+ _LIBCPP_HIDE_FROM_ABI explicit facet(size_t __refs = 0) : __shared_count(static_cast<long>(__refs) - 1) {}
+
+ ~facet() override;
+
+ // facet(const facet&) = delete; // effectively done in __shared_count
+ // void operator=(const facet&) = delete;
+
+private:
+ void __on_zero_shared() _NOEXCEPT override;
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI locale::id {
+ once_flag __flag_;
+ int32_t __id_;
+
+ static int32_t __next_id;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR id() : __id_(0) {}
+ void operator=(const id&) = delete;
+ id(const id&) = delete;
+
+public: // only needed for tests
+ long __get();
+
+ friend class locale;
+ friend class locale::__imp;
+};
+
+template <class _Facet>
+inline _LIBCPP_HIDE_FROM_ABI locale::locale(const locale& __other, _Facet* __f) {
+ __install_ctor(__other, __f, __f ? __f->id.__get() : 0);
+}
+
+template <class _Facet>
+locale locale::combine(const locale& __other) const {
+ if (!std::has_facet<_Facet>(__other))
+ __throw_runtime_error("locale::combine: locale missing facet");
+
+ return locale(*this, &const_cast<_Facet&>(std::use_facet<_Facet>(__other)));
+}
+
+template <class _Facet>
+inline _LIBCPP_HIDE_FROM_ABI bool has_facet(const locale& __l) _NOEXCEPT {
+ return __l.has_facet(_Facet::id);
+}
+
+template <class _Facet>
+inline _LIBCPP_HIDE_FROM_ABI const _Facet& use_facet(const locale& __l) {
+ return static_cast<const _Facet&>(*__l.use_facet(_Facet::id));
+}
+
+// template <class _CharT> class collate;
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS collate : public locale::facet {
+public:
+ typedef _CharT char_type;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit collate(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI int
+ compare(const char_type* __lo1, const char_type* __hi1, const char_type* __lo2, const char_type* __hi2) const {
+ return do_compare(__lo1, __hi1, __lo2, __hi2);
+ }
+
+ // FIXME(EricWF): The _LIBCPP_ALWAYS_INLINE is needed on Windows to work
+ // around a dllimport bug that expects an external instantiation.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE string_type
+ transform(const char_type* __lo, const char_type* __hi) const {
+ return do_transform(__lo, __hi);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI long hash(const char_type* __lo, const char_type* __hi) const { return do_hash(__lo, __hi); }
+
+ static locale::id id;
+
+protected:
+ ~collate() override;
+ virtual int
+ do_compare(const char_type* __lo1, const char_type* __hi1, const char_type* __lo2, const char_type* __hi2) const;
+ virtual string_type do_transform(const char_type* __lo, const char_type* __hi) const {
+ return string_type(__lo, __hi);
+ }
+ virtual long do_hash(const char_type* __lo, const char_type* __hi) const;
+};
+
+template <class _CharT>
+locale::id collate<_CharT>::id;
+
+template <class _CharT>
+collate<_CharT>::~collate() {}
+
+template <class _CharT>
+int collate<_CharT>::do_compare(
+ const char_type* __lo1, const char_type* __hi1, const char_type* __lo2, const char_type* __hi2) const {
+ for (; __lo2 != __hi2; ++__lo1, ++__lo2) {
+ if (__lo1 == __hi1 || *__lo1 < *__lo2)
+ return -1;
+ if (*__lo2 < *__lo1)
+ return 1;
+ }
+ return __lo1 != __hi1;
+}
+
+template <class _CharT>
+long collate<_CharT>::do_hash(const char_type* __lo, const char_type* __hi) const {
+ size_t __h = 0;
+ const size_t __sr = __CHAR_BIT__ * sizeof(size_t) - 8;
+ const size_t __mask = size_t(0xF) << (__sr + 4);
+ for (const char_type* __p = __lo; __p != __hi; ++__p) {
+ __h = (__h << 4) + static_cast<size_t>(*__p);
+ size_t __g = __h & __mask;
+ __h ^= __g | (__g >> __sr);
+ }
+ return static_cast<long>(__h);
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS collate<char>;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS collate<wchar_t>;
+#endif
+
+// template <class CharT> class collate_byname;
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS collate_byname;
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI collate_byname<char> : public collate<char> {
+ locale_t __l_;
+
+public:
+ typedef char char_type;
+ typedef basic_string<char_type> string_type;
+
+ explicit collate_byname(const char* __n, size_t __refs = 0);
+ explicit collate_byname(const string& __n, size_t __refs = 0);
+
+protected:
+ ~collate_byname() override;
+ int do_compare(
+ const char_type* __lo1, const char_type* __hi1, const char_type* __lo2, const char_type* __hi2) const override;
+ string_type do_transform(const char_type* __lo, const char_type* __hi) const override;
+};
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI collate_byname<wchar_t> : public collate<wchar_t> {
+ locale_t __l_;
+
+public:
+ typedef wchar_t char_type;
+ typedef basic_string<char_type> string_type;
+
+ explicit collate_byname(const char* __n, size_t __refs = 0);
+ explicit collate_byname(const string& __n, size_t __refs = 0);
+
+protected:
+ ~collate_byname() override;
+
+ int do_compare(
+ const char_type* __lo1, const char_type* __hi1, const char_type* __lo2, const char_type* __hi2) const override;
+ string_type do_transform(const char_type* __lo, const char_type* __hi) const override;
+};
+#endif
+
+template <class _CharT, class _Traits, class _Allocator>
+bool locale::operator()(const basic_string<_CharT, _Traits, _Allocator>& __x,
+ const basic_string<_CharT, _Traits, _Allocator>& __y) const {
+ return std::use_facet<std::collate<_CharT> >(*this).compare(
+ __x.data(), __x.data() + __x.size(), __y.data(), __y.data() + __y.size()) < 0;
+}
+
+// template <class charT> class ctype
+
+class _LIBCPP_EXPORTED_FROM_ABI ctype_base {
+public:
+#if defined(_LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE)
+ typedef unsigned long mask;
+ static const mask space = 1 << 0;
+ static const mask print = 1 << 1;
+ static const mask cntrl = 1 << 2;
+ static const mask upper = 1 << 3;
+ static const mask lower = 1 << 4;
+ static const mask alpha = 1 << 5;
+ static const mask digit = 1 << 6;
+ static const mask punct = 1 << 7;
+ static const mask xdigit = 1 << 8;
+ static const mask blank = 1 << 9;
+# if defined(__BIONIC__)
+ // Historically this was a part of regex_traits rather than ctype_base. The
+ // historical value of the constant is preserved for ABI compatibility.
+ static const mask __regex_word = 0x8000;
+# else
+ static const mask __regex_word = 1 << 10;
+# endif // defined(__BIONIC__)
+#elif defined(__GLIBC__)
+ typedef unsigned short mask;
+ static const mask space = _ISspace;
+ static const mask print = _ISprint;
+ static const mask cntrl = _IScntrl;
+ static const mask upper = _ISupper;
+ static const mask lower = _ISlower;
+ static const mask alpha = _ISalpha;
+ static const mask digit = _ISdigit;
+ static const mask punct = _ISpunct;
+ static const mask xdigit = _ISxdigit;
+ static const mask blank = _ISblank;
+# if defined(__mips__) || (BYTE_ORDER == BIG_ENDIAN)
+ static const mask __regex_word = static_cast<mask>(_ISbit(15));
+# else
+ static const mask __regex_word = 0x80;
+# endif
+#elif defined(_LIBCPP_MSVCRT_LIKE)
+ typedef unsigned short mask;
+ static const mask space = _SPACE;
+ static const mask print = _BLANK | _PUNCT | _ALPHA | _DIGIT;
+ static const mask cntrl = _CONTROL;
+ static const mask upper = _UPPER;
+ static const mask lower = _LOWER;
+ static const mask alpha = _ALPHA;
+ static const mask digit = _DIGIT;
+ static const mask punct = _PUNCT;
+ static const mask xdigit = _HEX;
+ static const mask blank = _BLANK;
+ static const mask __regex_word = 0x4000; // 0x8000 and 0x0100 and 0x00ff are used
+# define _LIBCPP_CTYPE_MASK_IS_COMPOSITE_PRINT
+# define _LIBCPP_CTYPE_MASK_IS_COMPOSITE_ALPHA
+#elif defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__)
+# ifdef __APPLE__
+ typedef __uint32_t mask;
+# elif defined(__FreeBSD__)
+ typedef unsigned long mask;
+# elif defined(__NetBSD__)
+ typedef unsigned short mask;
+# endif
+ static const mask space = _CTYPE_S;
+ static const mask print = _CTYPE_R;
+ static const mask cntrl = _CTYPE_C;
+ static const mask upper = _CTYPE_U;
+ static const mask lower = _CTYPE_L;
+ static const mask alpha = _CTYPE_A;
+ static const mask digit = _CTYPE_D;
+ static const mask punct = _CTYPE_P;
+ static const mask xdigit = _CTYPE_X;
+
+# if defined(__NetBSD__)
+ static const mask blank = _CTYPE_BL;
+ // NetBSD defines classes up to 0x2000
+ // see sys/ctype_bits.h, _CTYPE_Q
+ static const mask __regex_word = 0x8000;
+# else
+ static const mask blank = _CTYPE_B;
+ static const mask __regex_word = 0x80;
+# endif
+#elif defined(_AIX)
+ typedef unsigned int mask;
+ static const mask space = _ISSPACE;
+ static const mask print = _ISPRINT;
+ static const mask cntrl = _ISCNTRL;
+ static const mask upper = _ISUPPER;
+ static const mask lower = _ISLOWER;
+ static const mask alpha = _ISALPHA;
+ static const mask digit = _ISDIGIT;
+ static const mask punct = _ISPUNCT;
+ static const mask xdigit = _ISXDIGIT;
+ static const mask blank = _ISBLANK;
+ static const mask __regex_word = 0x8000;
+#elif defined(_NEWLIB_VERSION)
+ // Same type as Newlib's _ctype_ array in newlib/libc/include/ctype.h.
+ typedef char mask;
+ // In case char is signed, static_cast is needed to avoid warning on
+ // positive value becomming negative.
+ static const mask space = static_cast<mask>(_S);
+ static const mask print = static_cast<mask>(_P | _U | _L | _N | _B);
+ static const mask cntrl = static_cast<mask>(_C);
+ static const mask upper = static_cast<mask>(_U);
+ static const mask lower = static_cast<mask>(_L);
+ static const mask alpha = static_cast<mask>(_U | _L);
+ static const mask digit = static_cast<mask>(_N);
+ static const mask punct = static_cast<mask>(_P);
+ static const mask xdigit = static_cast<mask>(_X | _N);
+ static const mask blank = static_cast<mask>(_B);
+ // mask is already fully saturated, use a different type in regex_type_traits.
+ static const unsigned short __regex_word = 0x100;
+# define _LIBCPP_CTYPE_MASK_IS_COMPOSITE_PRINT
+# define _LIBCPP_CTYPE_MASK_IS_COMPOSITE_ALPHA
+# define _LIBCPP_CTYPE_MASK_IS_COMPOSITE_XDIGIT
+#elif defined(__MVS__)
+# if defined(__NATIVE_ASCII_F)
+ typedef unsigned int mask;
+ static const mask space = _ISSPACE_A;
+ static const mask print = _ISPRINT_A;
+ static const mask cntrl = _ISCNTRL_A;
+ static const mask upper = _ISUPPER_A;
+ static const mask lower = _ISLOWER_A;
+ static const mask alpha = _ISALPHA_A;
+ static const mask digit = _ISDIGIT_A;
+ static const mask punct = _ISPUNCT_A;
+ static const mask xdigit = _ISXDIGIT_A;
+ static const mask blank = _ISBLANK_A;
+# else
+ typedef unsigned short mask;
+ static const mask space = __ISSPACE;
+ static const mask print = __ISPRINT;
+ static const mask cntrl = __ISCNTRL;
+ static const mask upper = __ISUPPER;
+ static const mask lower = __ISLOWER;
+ static const mask alpha = __ISALPHA;
+ static const mask digit = __ISDIGIT;
+ static const mask punct = __ISPUNCT;
+ static const mask xdigit = __ISXDIGIT;
+ static const mask blank = __ISBLANK;
+# endif
+ static const mask __regex_word = 0x8000;
+#else
+# error unknown rune table for this platform -- do you mean to define _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE?
+#endif
+ static const mask alnum = alpha | digit;
+ static const mask graph = alnum | punct;
+
+ _LIBCPP_HIDE_FROM_ABI ctype_base() {}
+
+ static_assert((__regex_word & ~(std::make_unsigned<mask>::type)(space | print | cntrl | upper | lower | alpha |
+ digit | punct | xdigit | blank)) == __regex_word,
+ "__regex_word can't overlap other bits");
+};
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS ctype;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI ctype<wchar_t> : public locale::facet, public ctype_base {
+public:
+ typedef wchar_t char_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit ctype(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI bool is(mask __m, char_type __c) const { return do_is(__m, __c); }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* is(const char_type* __low, const char_type* __high, mask* __vec) const {
+ return do_is(__low, __high, __vec);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* scan_is(mask __m, const char_type* __low, const char_type* __high) const {
+ return do_scan_is(__m, __low, __high);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* scan_not(mask __m, const char_type* __low, const char_type* __high) const {
+ return do_scan_not(__m, __low, __high);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI char_type toupper(char_type __c) const { return do_toupper(__c); }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* toupper(char_type* __low, const char_type* __high) const {
+ return do_toupper(__low, __high);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI char_type tolower(char_type __c) const { return do_tolower(__c); }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* tolower(char_type* __low, const char_type* __high) const {
+ return do_tolower(__low, __high);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI char_type widen(char __c) const { return do_widen(__c); }
+
+ _LIBCPP_HIDE_FROM_ABI const char* widen(const char* __low, const char* __high, char_type* __to) const {
+ return do_widen(__low, __high, __to);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI char narrow(char_type __c, char __dfault) const { return do_narrow(__c, __dfault); }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type*
+ narrow(const char_type* __low, const char_type* __high, char __dfault, char* __to) const {
+ return do_narrow(__low, __high, __dfault, __to);
+ }
+
+ static locale::id id;
+
+protected:
+ ~ctype() override;
+ virtual bool do_is(mask __m, char_type __c) const;
+ virtual const char_type* do_is(const char_type* __low, const char_type* __high, mask* __vec) const;
+ virtual const char_type* do_scan_is(mask __m, const char_type* __low, const char_type* __high) const;
+ virtual const char_type* do_scan_not(mask __m, const char_type* __low, const char_type* __high) const;
+ virtual char_type do_toupper(char_type) const;
+ virtual const char_type* do_toupper(char_type* __low, const char_type* __high) const;
+ virtual char_type do_tolower(char_type) const;
+ virtual const char_type* do_tolower(char_type* __low, const char_type* __high) const;
+ virtual char_type do_widen(char) const;
+ virtual const char* do_widen(const char* __low, const char* __high, char_type* __dest) const;
+ virtual char do_narrow(char_type, char __dfault) const;
+ virtual const char_type*
+ do_narrow(const char_type* __low, const char_type* __high, char __dfault, char* __dest) const;
+};
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI ctype<char> : public locale::facet, public ctype_base {
+ const mask* __tab_;
+ bool __del_;
+
+public:
+ typedef char char_type;
+
+ explicit ctype(const mask* __tab = nullptr, bool __del = false, size_t __refs = 0);
+
+ _LIBCPP_HIDE_FROM_ABI bool is(mask __m, char_type __c) const {
+ return isascii(__c) ? (__tab_[static_cast<int>(__c)] & __m) != 0 : false;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* is(const char_type* __low, const char_type* __high, mask* __vec) const {
+ for (; __low != __high; ++__low, ++__vec)
+ *__vec = isascii(*__low) ? __tab_[static_cast<int>(*__low)] : 0;
+ return __low;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* scan_is(mask __m, const char_type* __low, const char_type* __high) const {
+ for (; __low != __high; ++__low)
+ if (isascii(*__low) && (__tab_[static_cast<int>(*__low)] & __m))
+ break;
+ return __low;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* scan_not(mask __m, const char_type* __low, const char_type* __high) const {
+ for (; __low != __high; ++__low)
+ if (!isascii(*__low) || !(__tab_[static_cast<int>(*__low)] & __m))
+ break;
+ return __low;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI char_type toupper(char_type __c) const { return do_toupper(__c); }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* toupper(char_type* __low, const char_type* __high) const {
+ return do_toupper(__low, __high);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI char_type tolower(char_type __c) const { return do_tolower(__c); }
+
+ _LIBCPP_HIDE_FROM_ABI const char_type* tolower(char_type* __low, const char_type* __high) const {
+ return do_tolower(__low, __high);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI char_type widen(char __c) const { return do_widen(__c); }
+
+ _LIBCPP_HIDE_FROM_ABI const char* widen(const char* __low, const char* __high, char_type* __to) const {
+ return do_widen(__low, __high, __to);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI char narrow(char_type __c, char __dfault) const { return do_narrow(__c, __dfault); }
+
+ _LIBCPP_HIDE_FROM_ABI const char*
+ narrow(const char_type* __low, const char_type* __high, char __dfault, char* __to) const {
+ return do_narrow(__low, __high, __dfault, __to);
+ }
+
+ static locale::id id;
+
+#ifdef _CACHED_RUNES
+ static const size_t table_size = _CACHED_RUNES;
+#else
+ static const size_t table_size = 256; // FIXME: Don't hardcode this.
+#endif
+ _LIBCPP_HIDE_FROM_ABI const mask* table() const _NOEXCEPT { return __tab_; }
+ static const mask* classic_table() _NOEXCEPT;
+#if defined(__GLIBC__) || defined(__EMSCRIPTEN__)
+ static const int* __classic_upper_table() _NOEXCEPT;
+ static const int* __classic_lower_table() _NOEXCEPT;
+#endif
+#if defined(__NetBSD__)
+ static const short* __classic_upper_table() _NOEXCEPT;
+ static const short* __classic_lower_table() _NOEXCEPT;
+#endif
+#if defined(__MVS__)
+ static const unsigned short* __classic_upper_table() _NOEXCEPT;
+ static const unsigned short* __classic_lower_table() _NOEXCEPT;
+#endif
+
+protected:
+ ~ctype() override;
+ virtual char_type do_toupper(char_type __c) const;
+ virtual const char_type* do_toupper(char_type* __low, const char_type* __high) const;
+ virtual char_type do_tolower(char_type __c) const;
+ virtual const char_type* do_tolower(char_type* __low, const char_type* __high) const;
+ virtual char_type do_widen(char __c) const;
+ virtual const char* do_widen(const char* __low, const char* __high, char_type* __to) const;
+ virtual char do_narrow(char_type __c, char __dfault) const;
+ virtual const char* do_narrow(const char_type* __low, const char_type* __high, char __dfault, char* __to) const;
+};
+
+// template <class CharT> class ctype_byname;
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS ctype_byname;
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI ctype_byname<char> : public ctype<char> {
+ locale_t __l_;
+
+public:
+ explicit ctype_byname(const char*, size_t = 0);
+ explicit ctype_byname(const string&, size_t = 0);
+
+protected:
+ ~ctype_byname() override;
+ char_type do_toupper(char_type) const override;
+ const char_type* do_toupper(char_type* __low, const char_type* __high) const override;
+ char_type do_tolower(char_type) const override;
+ const char_type* do_tolower(char_type* __low, const char_type* __high) const override;
+};
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI ctype_byname<wchar_t> : public ctype<wchar_t> {
+ locale_t __l_;
+
+public:
+ explicit ctype_byname(const char*, size_t = 0);
+ explicit ctype_byname(const string&, size_t = 0);
+
+protected:
+ ~ctype_byname() override;
+ bool do_is(mask __m, char_type __c) const override;
+ const char_type* do_is(const char_type* __low, const char_type* __high, mask* __vec) const override;
+ const char_type* do_scan_is(mask __m, const char_type* __low, const char_type* __high) const override;
+ const char_type* do_scan_not(mask __m, const char_type* __low, const char_type* __high) const override;
+ char_type do_toupper(char_type) const override;
+ const char_type* do_toupper(char_type* __low, const char_type* __high) const override;
+ char_type do_tolower(char_type) const override;
+ const char_type* do_tolower(char_type* __low, const char_type* __high) const override;
+ char_type do_widen(char) const override;
+ const char* do_widen(const char* __low, const char* __high, char_type* __dest) const override;
+ char do_narrow(char_type, char __dfault) const override;
+ const char_type*
+ do_narrow(const char_type* __low, const char_type* __high, char __dfault, char* __dest) const override;
+};
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool isspace(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::space, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool isprint(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::print, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool iscntrl(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::cntrl, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool isupper(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::upper, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool islower(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::lower, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool isalpha(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::alpha, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool isdigit(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::digit, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool ispunct(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::punct, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool isxdigit(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::xdigit, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool isalnum(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::alnum, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI bool isgraph(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::graph, __c);
+}
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI bool isblank(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).is(ctype_base::blank, __c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI _CharT toupper(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).toupper(__c);
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI _CharT tolower(_CharT __c, const locale& __loc) {
+ return std::use_facet<ctype<_CharT> >(__loc).tolower(__c);
+}
+
+// codecvt_base
+
+class _LIBCPP_EXPORTED_FROM_ABI codecvt_base {
+public:
+ _LIBCPP_HIDE_FROM_ABI codecvt_base() {}
+ enum result { ok, partial, error, noconv };
+};
+
+// template <class internT, class externT, class stateT> class codecvt;
+
+template <class _InternT, class _ExternT, class _StateT>
+class _LIBCPP_TEMPLATE_VIS codecvt;
+
+// template <> class codecvt<char, char, mbstate_t>
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI codecvt<char, char, mbstate_t> : public locale::facet, public codecvt_base {
+public:
+ typedef char intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI result
+ out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const {
+ return do_out(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const {
+ return do_unshift(__st, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const {
+ return do_in(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int encoding() const _NOEXCEPT { return do_encoding(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool always_noconv() const _NOEXCEPT { return do_always_noconv(); }
+
+ _LIBCPP_HIDE_FROM_ABI int
+ length(state_type& __st, const extern_type* __frm, const extern_type* __end, size_t __mx) const {
+ return do_length(__st, __frm, __end, __mx);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int max_length() const _NOEXCEPT { return do_max_length(); }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(const char*, size_t __refs = 0) : locale::facet(__refs) {}
+
+ ~codecvt() override;
+
+ virtual result
+ do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const;
+ virtual result
+ do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const;
+ virtual result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const;
+ virtual int do_encoding() const _NOEXCEPT;
+ virtual bool do_always_noconv() const _NOEXCEPT;
+ virtual int do_length(state_type& __st, const extern_type* __frm, const extern_type* __end, size_t __mx) const;
+ virtual int do_max_length() const _NOEXCEPT;
+};
+
+// template <> class codecvt<wchar_t, char, mbstate_t>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI codecvt<wchar_t, char, mbstate_t> : public locale::facet, public codecvt_base {
+ locale_t __l_;
+
+public:
+ typedef wchar_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ explicit codecvt(size_t __refs = 0);
+
+ _LIBCPP_HIDE_FROM_ABI result
+ out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const {
+ return do_out(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const {
+ return do_unshift(__st, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const {
+ return do_in(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int encoding() const _NOEXCEPT { return do_encoding(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool always_noconv() const _NOEXCEPT { return do_always_noconv(); }
+
+ _LIBCPP_HIDE_FROM_ABI int
+ length(state_type& __st, const extern_type* __frm, const extern_type* __end, size_t __mx) const {
+ return do_length(__st, __frm, __end, __mx);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int max_length() const _NOEXCEPT { return do_max_length(); }
+
+ static locale::id id;
+
+protected:
+ explicit codecvt(const char*, size_t __refs = 0);
+
+ ~codecvt() override;
+
+ virtual result
+ do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const;
+ virtual result
+ do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const;
+ virtual result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const;
+ virtual int do_encoding() const _NOEXCEPT;
+ virtual bool do_always_noconv() const _NOEXCEPT;
+ virtual int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const;
+ virtual int do_max_length() const _NOEXCEPT;
+};
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+// template <> class codecvt<char16_t, char, mbstate_t> // deprecated in C++20
+
+template <>
+class _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_EXPORTED_FROM_ABI codecvt<char16_t, char, mbstate_t>
+ : public locale::facet, public codecvt_base {
+public:
+ typedef char16_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI result
+ out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const {
+ return do_out(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const {
+ return do_unshift(__st, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const {
+ return do_in(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int encoding() const _NOEXCEPT { return do_encoding(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool always_noconv() const _NOEXCEPT { return do_always_noconv(); }
+
+ _LIBCPP_HIDE_FROM_ABI int
+ length(state_type& __st, const extern_type* __frm, const extern_type* __end, size_t __mx) const {
+ return do_length(__st, __frm, __end, __mx);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int max_length() const _NOEXCEPT { return do_max_length(); }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(const char*, size_t __refs = 0) : locale::facet(__refs) {}
+
+ ~codecvt() override;
+
+ virtual result
+ do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const;
+ virtual result
+ do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const;
+ virtual result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const;
+ virtual int do_encoding() const _NOEXCEPT;
+ virtual bool do_always_noconv() const _NOEXCEPT;
+ virtual int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const;
+ virtual int do_max_length() const _NOEXCEPT;
+};
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+
+// template <> class codecvt<char16_t, char8_t, mbstate_t> // C++20
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI codecvt<char16_t, char8_t, mbstate_t> : public locale::facet, public codecvt_base {
+public:
+ typedef char16_t intern_type;
+ typedef char8_t extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI result
+ out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const {
+ return do_out(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const {
+ return do_unshift(__st, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const {
+ return do_in(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int encoding() const _NOEXCEPT { return do_encoding(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool always_noconv() const _NOEXCEPT { return do_always_noconv(); }
+
+ _LIBCPP_HIDE_FROM_ABI int
+ length(state_type& __st, const extern_type* __frm, const extern_type* __end, size_t __mx) const {
+ return do_length(__st, __frm, __end, __mx);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int max_length() const _NOEXCEPT { return do_max_length(); }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(const char*, size_t __refs = 0) : locale::facet(__refs) {}
+
+ ~codecvt() override;
+
+ virtual result
+ do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const;
+ virtual result
+ do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const;
+ virtual result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const;
+ virtual int do_encoding() const _NOEXCEPT;
+ virtual bool do_always_noconv() const _NOEXCEPT;
+ virtual int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const;
+ virtual int do_max_length() const _NOEXCEPT;
+};
+
+#endif
+
+// template <> class codecvt<char32_t, char, mbstate_t> // deprecated in C++20
+
+template <>
+class _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_EXPORTED_FROM_ABI codecvt<char32_t, char, mbstate_t>
+ : public locale::facet, public codecvt_base {
+public:
+ typedef char32_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI result
+ out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const {
+ return do_out(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const {
+ return do_unshift(__st, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const {
+ return do_in(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int encoding() const _NOEXCEPT { return do_encoding(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool always_noconv() const _NOEXCEPT { return do_always_noconv(); }
+
+ _LIBCPP_HIDE_FROM_ABI int
+ length(state_type& __st, const extern_type* __frm, const extern_type* __end, size_t __mx) const {
+ return do_length(__st, __frm, __end, __mx);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int max_length() const _NOEXCEPT { return do_max_length(); }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(const char*, size_t __refs = 0) : locale::facet(__refs) {}
+
+ ~codecvt() override;
+
+ virtual result
+ do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const;
+ virtual result
+ do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const;
+ virtual result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const;
+ virtual int do_encoding() const _NOEXCEPT;
+ virtual bool do_always_noconv() const _NOEXCEPT;
+ virtual int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const;
+ virtual int do_max_length() const _NOEXCEPT;
+};
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+
+// template <> class codecvt<char32_t, char8_t, mbstate_t> // C++20
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI codecvt<char32_t, char8_t, mbstate_t> : public locale::facet, public codecvt_base {
+public:
+ typedef char32_t intern_type;
+ typedef char8_t extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI result
+ out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const {
+ return do_out(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const {
+ return do_unshift(__st, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result
+ in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const {
+ return do_in(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int encoding() const _NOEXCEPT { return do_encoding(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool always_noconv() const _NOEXCEPT { return do_always_noconv(); }
+
+ _LIBCPP_HIDE_FROM_ABI int
+ length(state_type& __st, const extern_type* __frm, const extern_type* __end, size_t __mx) const {
+ return do_length(__st, __frm, __end, __mx);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int max_length() const _NOEXCEPT { return do_max_length(); }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt(const char*, size_t __refs = 0) : locale::facet(__refs) {}
+
+ ~codecvt() override;
+
+ virtual result
+ do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const;
+ virtual result
+ do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const;
+ virtual result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const;
+ virtual int do_encoding() const _NOEXCEPT;
+ virtual bool do_always_noconv() const _NOEXCEPT;
+ virtual int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const;
+ virtual int do_max_length() const _NOEXCEPT;
+};
+
+#endif
+
+// template <class _InternT, class _ExternT, class _StateT> class codecvt_byname
+
+template <class _InternT, class _ExternT, class _StateT>
+class _LIBCPP_TEMPLATE_VIS codecvt_byname : public codecvt<_InternT, _ExternT, _StateT> {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt_byname(const char* __nm, size_t __refs = 0)
+ : codecvt<_InternT, _ExternT, _StateT>(__nm, __refs) {}
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt_byname(const string& __nm, size_t __refs = 0)
+ : codecvt<_InternT, _ExternT, _StateT>(__nm.c_str(), __refs) {}
+
+protected:
+ ~codecvt_byname() override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _InternT, class _ExternT, class _StateT>
+codecvt_byname<_InternT, _ExternT, _StateT>::~codecvt_byname() {}
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS codecvt_byname<char, char, mbstate_t>;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS codecvt_byname<wchar_t, char, mbstate_t>;
+#endif
+extern template class _LIBCPP_DEPRECATED_IN_CXX20
+_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS codecvt_byname<char16_t, char, mbstate_t>; // deprecated in C++20
+extern template class _LIBCPP_DEPRECATED_IN_CXX20
+_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS codecvt_byname<char32_t, char, mbstate_t>; // deprecated in C++20
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS codecvt_byname<char16_t, char8_t, mbstate_t>; // C++20
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS codecvt_byname<char32_t, char8_t, mbstate_t>; // C++20
+#endif
+
+template <size_t _Np>
+struct __narrow_to_utf8 {
+ template <class _OutputIterator, class _CharT>
+ _OutputIterator operator()(_OutputIterator __s, const _CharT* __wb, const _CharT* __we) const;
+};
+
+template <>
+struct __narrow_to_utf8<8> {
+ template <class _OutputIterator, class _CharT>
+ _LIBCPP_HIDE_FROM_ABI _OutputIterator operator()(_OutputIterator __s, const _CharT* __wb, const _CharT* __we) const {
+ for (; __wb < __we; ++__wb, ++__s)
+ *__s = *__wb;
+ return __s;
+ }
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+struct _LIBCPP_EXPORTED_FROM_ABI __narrow_to_utf8<16> : public codecvt<char16_t, char, mbstate_t> {
+ _LIBCPP_HIDE_FROM_ABI __narrow_to_utf8() : codecvt<char16_t, char, mbstate_t>(1) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+ ~__narrow_to_utf8() override;
+
+ template <class _OutputIterator, class _CharT>
+ _LIBCPP_HIDE_FROM_ABI _OutputIterator operator()(_OutputIterator __s, const _CharT* __wb, const _CharT* __we) const {
+ result __r = ok;
+ mbstate_t __mb;
+ while (__wb < __we && __r != error) {
+ const int __sz = 32;
+ char __buf[__sz];
+ char* __bn;
+ const char16_t* __wn = (const char16_t*)__wb;
+ __r = do_out(__mb, (const char16_t*)__wb, (const char16_t*)__we, __wn, __buf, __buf + __sz, __bn);
+ if (__r == codecvt_base::error || __wn == (const char16_t*)__wb)
+ __throw_runtime_error("locale not supported");
+ for (const char* __p = __buf; __p < __bn; ++__p, ++__s)
+ *__s = *__p;
+ __wb = (const _CharT*)__wn;
+ }
+ return __s;
+ }
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+struct _LIBCPP_EXPORTED_FROM_ABI __narrow_to_utf8<32> : public codecvt<char32_t, char, mbstate_t> {
+ _LIBCPP_HIDE_FROM_ABI __narrow_to_utf8() : codecvt<char32_t, char, mbstate_t>(1) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+ ~__narrow_to_utf8() override;
+
+ template <class _OutputIterator, class _CharT>
+ _LIBCPP_HIDE_FROM_ABI _OutputIterator operator()(_OutputIterator __s, const _CharT* __wb, const _CharT* __we) const {
+ result __r = ok;
+ mbstate_t __mb;
+ while (__wb < __we && __r != error) {
+ const int __sz = 32;
+ char __buf[__sz];
+ char* __bn;
+ const char32_t* __wn = (const char32_t*)__wb;
+ __r = do_out(__mb, (const char32_t*)__wb, (const char32_t*)__we, __wn, __buf, __buf + __sz, __bn);
+ if (__r == codecvt_base::error || __wn == (const char32_t*)__wb)
+ __throw_runtime_error("locale not supported");
+ for (const char* __p = __buf; __p < __bn; ++__p, ++__s)
+ *__s = *__p;
+ __wb = (const _CharT*)__wn;
+ }
+ return __s;
+ }
+};
+
+template <size_t _Np>
+struct __widen_from_utf8 {
+ template <class _OutputIterator>
+ _OutputIterator operator()(_OutputIterator __s, const char* __nb, const char* __ne) const;
+};
+
+template <>
+struct __widen_from_utf8<8> {
+ template <class _OutputIterator>
+ _LIBCPP_HIDE_FROM_ABI _OutputIterator operator()(_OutputIterator __s, const char* __nb, const char* __ne) const {
+ for (; __nb < __ne; ++__nb, ++__s)
+ *__s = *__nb;
+ return __s;
+ }
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+struct _LIBCPP_EXPORTED_FROM_ABI __widen_from_utf8<16> : public codecvt<char16_t, char, mbstate_t> {
+ _LIBCPP_HIDE_FROM_ABI __widen_from_utf8() : codecvt<char16_t, char, mbstate_t>(1) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+ ~__widen_from_utf8() override;
+
+ template <class _OutputIterator>
+ _LIBCPP_HIDE_FROM_ABI _OutputIterator operator()(_OutputIterator __s, const char* __nb, const char* __ne) const {
+ result __r = ok;
+ mbstate_t __mb;
+ while (__nb < __ne && __r != error) {
+ const int __sz = 32;
+ char16_t __buf[__sz];
+ char16_t* __bn;
+ const char* __nn = __nb;
+ __r = do_in(__mb, __nb, __ne - __nb > __sz ? __nb + __sz : __ne, __nn, __buf, __buf + __sz, __bn);
+ if (__r == codecvt_base::error || __nn == __nb)
+ __throw_runtime_error("locale not supported");
+ for (const char16_t* __p = __buf; __p < __bn; ++__p, ++__s)
+ *__s = *__p;
+ __nb = __nn;
+ }
+ return __s;
+ }
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+struct _LIBCPP_EXPORTED_FROM_ABI __widen_from_utf8<32> : public codecvt<char32_t, char, mbstate_t> {
+ _LIBCPP_HIDE_FROM_ABI __widen_from_utf8() : codecvt<char32_t, char, mbstate_t>(1) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+ ~__widen_from_utf8() override;
+
+ template <class _OutputIterator>
+ _LIBCPP_HIDE_FROM_ABI _OutputIterator operator()(_OutputIterator __s, const char* __nb, const char* __ne) const {
+ result __r = ok;
+ mbstate_t __mb;
+ while (__nb < __ne && __r != error) {
+ const int __sz = 32;
+ char32_t __buf[__sz];
+ char32_t* __bn;
+ const char* __nn = __nb;
+ __r = do_in(__mb, __nb, __ne - __nb > __sz ? __nb + __sz : __ne, __nn, __buf, __buf + __sz, __bn);
+ if (__r == codecvt_base::error || __nn == __nb)
+ __throw_runtime_error("locale not supported");
+ for (const char32_t* __p = __buf; __p < __bn; ++__p, ++__s)
+ *__s = *__p;
+ __nb = __nn;
+ }
+ return __s;
+ }
+};
+
+// template <class charT> class numpunct
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS numpunct;
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI numpunct<char> : public locale::facet {
+public:
+ typedef char char_type;
+ typedef basic_string<char_type> string_type;
+
+ explicit numpunct(size_t __refs = 0);
+
+ _LIBCPP_HIDE_FROM_ABI char_type decimal_point() const { return do_decimal_point(); }
+ _LIBCPP_HIDE_FROM_ABI char_type thousands_sep() const { return do_thousands_sep(); }
+ _LIBCPP_HIDE_FROM_ABI string grouping() const { return do_grouping(); }
+ _LIBCPP_HIDE_FROM_ABI string_type truename() const { return do_truename(); }
+ _LIBCPP_HIDE_FROM_ABI string_type falsename() const { return do_falsename(); }
+
+ static locale::id id;
+
+protected:
+ ~numpunct() override;
+ virtual char_type do_decimal_point() const;
+ virtual char_type do_thousands_sep() const;
+ virtual string do_grouping() const;
+ virtual string_type do_truename() const;
+ virtual string_type do_falsename() const;
+
+ char_type __decimal_point_;
+ char_type __thousands_sep_;
+ string __grouping_;
+};
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI numpunct<wchar_t> : public locale::facet {
+public:
+ typedef wchar_t char_type;
+ typedef basic_string<char_type> string_type;
+
+ explicit numpunct(size_t __refs = 0);
+
+ _LIBCPP_HIDE_FROM_ABI char_type decimal_point() const { return do_decimal_point(); }
+ _LIBCPP_HIDE_FROM_ABI char_type thousands_sep() const { return do_thousands_sep(); }
+ _LIBCPP_HIDE_FROM_ABI string grouping() const { return do_grouping(); }
+ _LIBCPP_HIDE_FROM_ABI string_type truename() const { return do_truename(); }
+ _LIBCPP_HIDE_FROM_ABI string_type falsename() const { return do_falsename(); }
+
+ static locale::id id;
+
+protected:
+ ~numpunct() override;
+ virtual char_type do_decimal_point() const;
+ virtual char_type do_thousands_sep() const;
+ virtual string do_grouping() const;
+ virtual string_type do_truename() const;
+ virtual string_type do_falsename() const;
+
+ char_type __decimal_point_;
+ char_type __thousands_sep_;
+ string __grouping_;
+};
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+// template <class charT> class numpunct_byname
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS numpunct_byname;
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI numpunct_byname<char> : public numpunct<char> {
+public:
+ typedef char char_type;
+ typedef basic_string<char_type> string_type;
+
+ explicit numpunct_byname(const char* __nm, size_t __refs = 0);
+ explicit numpunct_byname(const string& __nm, size_t __refs = 0);
+
+protected:
+ ~numpunct_byname() override;
+
+private:
+ void __init(const char*);
+};
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI numpunct_byname<wchar_t> : public numpunct<wchar_t> {
+public:
+ typedef wchar_t char_type;
+ typedef basic_string<char_type> string_type;
+
+ explicit numpunct_byname(const char* __nm, size_t __refs = 0);
+ explicit numpunct_byname(const string& __nm, size_t __refs = 0);
+
+protected:
+ ~numpunct_byname() override;
+
+private:
+ void __init(const char*);
+};
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___LOCALE
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api.h
new file mode 100644
index 00000000000000..8c000c558c5279
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api.h
@@ -0,0 +1,98 @@
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_DIR_LOCALE_BASE_API_H
+#define _LIBCPP___LOCALE_DIR_LOCALE_BASE_API_H
+
+#if defined(_LIBCPP_MSVCRT_LIKE)
+# include <__locale_dir/locale_base_api/win32.h>
+#elif defined(_AIX) || defined(__MVS__)
+# include <__locale_dir/locale_base_api/ibm.h>
+#elif defined(__ANDROID__)
+# include <__locale_dir/locale_base_api/android.h>
+#elif defined(__sun__)
+# include <__locale_dir/locale_base_api/solaris.h>
+#elif defined(_NEWLIB_VERSION)
+# include <__locale_dir/locale_base_api/newlib.h>
+#elif defined(__OpenBSD__)
+# include <__locale_dir/locale_base_api/openbsd.h>
+#elif defined(__Fuchsia__)
+# include <__locale_dir/locale_base_api/fuchsia.h>
+#elif defined(__wasi__) || defined(_LIBCPP_HAS_MUSL_LIBC)
+# include <__locale_dir/locale_base_api/musl.h>
+#elif defined(__APPLE__) || defined(__FreeBSD__)
+# include <xlocale.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+/*
+The platform-specific headers have to provide the following interface:
+
+// TODO: rename this to __libcpp_locale_t
+using locale_t = implementation-defined;
+
+implementation-defined __libcpp_mb_cur_max_l(locale_t);
+wint_t __libcpp_btowc_l(int, locale_t);
+int __libcpp_wctob_l(wint_t, locale_t);
+size_t __libcpp_wcsnrtombs_l(char* dest, const wchar_t** src, size_t wide_char_count, size_t len, mbstate_t, locale_t);
+size_t __libcpp_wcrtomb_l(char* str, wchar_t wide_char, mbstate_t*, locale_t);
+size_t __libcpp_mbsnrtowcs_l(wchar_t* dest, const char** src, size_t max_out, size_t len, mbstate_t*, locale_t);
+size_t __libcpp_mbrtowc_l(wchar_t* dest, cosnt char* src, size_t count, mbstate_t*, locale_t);
+int __libcpp_mbtowc_l(wchar_t* dest, const char* src, size_t count, locale_t);
+size_t __libcpp_mbrlen_l(const char* str, size_t count, mbstate_t*, locale_t);
+lconv* __libcpp_localeconv_l(locale_t);
+size_t __libcpp_mbsrtowcs_l(wchar_t* dest, const char** src, size_t len, mbstate_t*, locale_t);
+int __libcpp_snprintf_l(char* dest, size_t buff_size, locale_t, const char* format, ...);
+int __libcpp_asprintf_l(char** dest, locale_t, const char* format, ...);
+int __libcpp_sscanf_l(const char* dest, locale_t, const char* format, ...);
+
+// TODO: change these to reserved names
+float strtof_l(const char* str, char** str_end, locale_t);
+double strtod_l(const char* str, char** str_end, locale_t);
+long double strtold_l(const char* str, char** str_end, locale_t);
+long long strtoll_l(const char* str, char** str_end, locale_t);
+unsigned long long strtoull_l(const char* str, char** str_end, locale_t);
+
+locale_t newlocale(int category_mask, const char* locale, locale_t base);
+void freelocale(locale_t);
+
+int islower_l(int ch, locale_t);
+int isupper_l(int ch, locale_t);
+int isdigit_l(int ch, locale_t);
+int isxdigit_l(int ch, locale_t);
+int strcoll_l(const char* lhs, const char* rhs, locale_t);
+size_t strxfrm_l(char* dst, const char* src, size_t n, locale_t);
+int wcscoll_l(const char* lhs, const char* rhs, locale_t);
+size_t wcsxfrm_l(wchar_t* dst, const wchar_t* src, size_t n, locale_t);
+int toupper_l(int ch, locale_t);
+int tolower_l(int ch, locale_t);
+int iswspace_l(wint_t ch, locale_t);
+int iswprint_l(wint_t ch, locale_t);
+int iswcntrl_l(wint_t ch, locale_t);
+int iswupper_l(wint_t ch, locale_t);
+int iswlower_l(wint_t ch, locale_t);
+int iswalpha_l(wint_t ch, locale_t);
+int iswblank_l(wint_t ch, locale_t);
+int iswdigit_l(wint_t ch, locale_t);
+int iswpunct_l(wint_t ch, locale_t);
+int iswxdigit_l(wint_t ch, locale_t);
+wint_t towupper_l(wint_t ch, locale_t);
+wint_t towlower_l(wint_t ch, locale_t);
+size_t strftime_l(char* str, size_t len, const char* format, const tm*, locale_t);
+
+
+These functions are equivalent to their C counterparts,
+except that locale_t is used instead of the current global locale.
+
+The variadic functions may be implemented as templates with a parameter pack instead of variadic functions.
+*/
+
+#endif // _LIBCPP___LOCALE_DIR_LOCALE_BASE_API_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/android.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/android.h
new file mode 100644
index 00000000000000..9965d8bbf6a2ec
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/android.h
@@ -0,0 +1,50 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_ANDROID_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_ANDROID_H
+
+#include <stdlib.h>
+
+// FIXME: Is this actually required?
+extern "C" {
+#include <xlocale.h>
+}
+
+#include <android/api-level.h>
+#if __ANDROID_API__ < 21
+# include <__support/xlocale/__posix_l_fallback.h>
+#endif
+
+// If we do not have this header, we are in a platform build rather than an NDK
+// build, which will always be at least as new as the ToT NDK, in which case we
+// don't need any of the inlines below since libc provides them.
+#if __has_include(<android/ndk-version.h>)
+# include <android/ndk-version.h>
+// In NDK versions later than 16, locale-aware functions are provided by
+// legacy_stdlib_inlines.h
+# if __NDK_MAJOR__ <= 16
+# if __ANDROID_API__ < 21
+# include <__support/xlocale/__strtonum_fallback.h>
+# elif __ANDROID_API__ < 26
+
+inline _LIBCPP_HIDE_FROM_ABI float strtof_l(const char* __nptr, char** __endptr, locale_t) {
+ return ::strtof(__nptr, __endptr);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI double strtod_l(const char* __nptr, char** __endptr, locale_t) {
+ return ::strtod(__nptr, __endptr);
+}
+
+# endif // __ANDROID_API__ < 26
+
+# endif // __NDK_MAJOR__ <= 16
+#endif // __has_include(<android/ndk-version.h>)
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_ANDROID_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/bsd_locale_defaults.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/bsd_locale_defaults.h
new file mode 100644
index 00000000000000..1f9607209842ca
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/bsd_locale_defaults.h
@@ -0,0 +1,36 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// The BSDs have lots of *_l functions. We don't want to define those symbols
+// on other platforms though, for fear of conflicts with user code. So here,
+// we will define the mapping from an internal macro to the real BSD symbol.
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_BSD_LOCALE_DEFAULTS_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_BSD_LOCALE_DEFAULTS_H
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#define __libcpp_mb_cur_max_l(loc) MB_CUR_MAX_L(loc)
+#define __libcpp_btowc_l(ch, loc) btowc_l(ch, loc)
+#define __libcpp_wctob_l(wch, loc) wctob_l(wch, loc)
+#define __libcpp_wcsnrtombs_l(dst, src, nwc, len, ps, loc) wcsnrtombs_l(dst, src, nwc, len, ps, loc)
+#define __libcpp_wcrtomb_l(src, wc, ps, loc) wcrtomb_l(src, wc, ps, loc)
+#define __libcpp_mbsnrtowcs_l(dst, src, nms, len, ps, loc) mbsnrtowcs_l(dst, src, nms, len, ps, loc)
+#define __libcpp_mbrtowc_l(pwc, s, n, ps, l) mbrtowc_l(pwc, s, n, ps, l)
+#define __libcpp_mbtowc_l(pwc, pmb, max, l) mbtowc_l(pwc, pmb, max, l)
+#define __libcpp_mbrlen_l(s, n, ps, l) mbrlen_l(s, n, ps, l)
+#define __libcpp_localeconv_l(l) localeconv_l(l)
+#define __libcpp_mbsrtowcs_l(dest, src, len, ps, l) mbsrtowcs_l(dest, src, len, ps, l)
+#define __libcpp_snprintf_l(...) snprintf_l(__VA_ARGS__)
+#define __libcpp_asprintf_l(...) asprintf_l(__VA_ARGS__)
+#define __libcpp_sscanf_l(...) sscanf_l(__VA_ARGS__)
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_BSD_LOCALE_DEFAULTS_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/bsd_locale_fallbacks.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/bsd_locale_fallbacks.h
new file mode 100644
index 00000000000000..76b94287cd6cc8
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/bsd_locale_fallbacks.h
@@ -0,0 +1,126 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// The BSDs have lots of *_l functions. This file provides reimplementations
+// of those functions for non-BSD platforms.
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_BSD_LOCALE_FALLBACKS_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_BSD_LOCALE_FALLBACKS_H
+
+#include <__locale_dir/locale_base_api/locale_guard.h>
+#include <cstdio>
+#include <stdarg.h>
+#include <stdlib.h>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+# include <cwchar>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+inline _LIBCPP_HIDE_FROM_ABI decltype(MB_CUR_MAX) __libcpp_mb_cur_max_l(locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return MB_CUR_MAX;
+}
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+inline _LIBCPP_HIDE_FROM_ABI wint_t __libcpp_btowc_l(int __c, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return btowc(__c);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_wctob_l(wint_t __c, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return wctob(__c);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t
+__libcpp_wcsnrtombs_l(char* __dest, const wchar_t** __src, size_t __nwc, size_t __len, mbstate_t* __ps, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return wcsnrtombs(__dest, __src, __nwc, __len, __ps);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t __libcpp_wcrtomb_l(char* __s, wchar_t __wc, mbstate_t* __ps, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return wcrtomb(__s, __wc, __ps);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t
+__libcpp_mbsnrtowcs_l(wchar_t* __dest, const char** __src, size_t __nms, size_t __len, mbstate_t* __ps, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return mbsnrtowcs(__dest, __src, __nms, __len, __ps);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t
+__libcpp_mbrtowc_l(wchar_t* __pwc, const char* __s, size_t __n, mbstate_t* __ps, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return mbrtowc(__pwc, __s, __n, __ps);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_mbtowc_l(wchar_t* __pwc, const char* __pmb, size_t __max, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return mbtowc(__pwc, __pmb, __max);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t __libcpp_mbrlen_l(const char* __s, size_t __n, mbstate_t* __ps, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return mbrlen(__s, __n, __ps);
+}
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+inline _LIBCPP_HIDE_FROM_ABI lconv* __libcpp_localeconv_l(locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return localeconv();
+}
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+inline _LIBCPP_HIDE_FROM_ABI size_t
+__libcpp_mbsrtowcs_l(wchar_t* __dest, const char** __src, size_t __len, mbstate_t* __ps, locale_t __l) {
+ __libcpp_locale_guard __current(__l);
+ return mbsrtowcs(__dest, __src, __len, __ps);
+}
+#endif
+
+inline _LIBCPP_ATTRIBUTE_FORMAT(__printf__, 4, 5) int __libcpp_snprintf_l(
+ char* __s, size_t __n, locale_t __l, const char* __format, ...) {
+ va_list __va;
+ va_start(__va, __format);
+ __libcpp_locale_guard __current(__l);
+ int __res = vsnprintf(__s, __n, __format, __va);
+ va_end(__va);
+ return __res;
+}
+
+inline _LIBCPP_ATTRIBUTE_FORMAT(__printf__, 3, 4) int __libcpp_asprintf_l(
+ char** __s, locale_t __l, const char* __format, ...) {
+ va_list __va;
+ va_start(__va, __format);
+ __libcpp_locale_guard __current(__l);
+ int __res = vasprintf(__s, __format, __va);
+ va_end(__va);
+ return __res;
+}
+
+inline _LIBCPP_ATTRIBUTE_FORMAT(__scanf__, 3, 4) int __libcpp_sscanf_l(
+ const char* __s, locale_t __l, const char* __format, ...) {
+ va_list __va;
+ va_start(__va, __format);
+ __libcpp_locale_guard __current(__l);
+ int __res = vsscanf(__s, __format, __va);
+ va_end(__va);
+ return __res;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_BSD_LOCALE_FALLBACKS_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/fuchsia.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/fuchsia.h
new file mode 100644
index 00000000000000..4c3440f981c6d0
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/fuchsia.h
@@ -0,0 +1,18 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_FUCHSIA_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_FUCHSIA_H
+
+#include <__support/xlocale/__posix_l_fallback.h>
+#include <__support/xlocale/__strtonum_fallback.h>
+#include <cstdlib>
+#include <cwchar>
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_FUCHSIA_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/ibm.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/ibm.h
new file mode 100644
index 00000000000000..01af20194428b9
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/ibm.h
@@ -0,0 +1,108 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_IBM_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_IBM_H
+
+#if defined(__MVS__)
+# include <__support/ibm/locale_mgmt_zos.h>
+#endif // defined(__MVS__)
+
+#include <locale.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+#include "cstdlib"
+
+#if defined(__MVS__)
+# include <wctype.h>
+// POSIX routines
+# include <__support/xlocale/__posix_l_fallback.h>
+#endif // defined(__MVS__)
+
+namespace {
+
+struct __setAndRestore {
+ explicit __setAndRestore(locale_t locale) {
+ if (locale == (locale_t)0) {
+ __cloc = newlocale(LC_ALL_MASK, "C", /* base */ (locale_t)0);
+ __stored = uselocale(__cloc);
+ } else {
+ __stored = uselocale(locale);
+ }
+ }
+
+ ~__setAndRestore() {
+ uselocale(__stored);
+ if (__cloc)
+ freelocale(__cloc);
+ }
+
+private:
+ locale_t __stored = (locale_t)0;
+ locale_t __cloc = (locale_t)0;
+};
+
+} // namespace
+
+// The following are not POSIX routines. These are quick-and-dirty hacks
+// to make things pretend to work
+inline _LIBCPP_HIDE_FROM_ABI long long strtoll_l(const char* __nptr, char** __endptr, int __base, locale_t locale) {
+ __setAndRestore __newloc(locale);
+ return ::strtoll(__nptr, __endptr, __base);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI double strtod_l(const char* __nptr, char** __endptr, locale_t locale) {
+ __setAndRestore __newloc(locale);
+ return ::strtod(__nptr, __endptr);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI float strtof_l(const char* __nptr, char** __endptr, locale_t locale) {
+ __setAndRestore __newloc(locale);
+ return ::strtof(__nptr, __endptr);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double strtold_l(const char* __nptr, char** __endptr, locale_t locale) {
+ __setAndRestore __newloc(locale);
+ return ::strtold(__nptr, __endptr);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI unsigned long long
+strtoull_l(const char* __nptr, char** __endptr, int __base, locale_t locale) {
+ __setAndRestore __newloc(locale);
+ return ::strtoull(__nptr, __endptr, __base);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_ATTRIBUTE_FORMAT(__printf__, 2, 0) int vasprintf(char** strp, const char* fmt, va_list ap) {
+ const size_t buff_size = 256;
+ if ((*strp = (char*)malloc(buff_size)) == NULL) {
+ return -1;
+ }
+
+ va_list ap_copy;
+ // va_copy may not be provided by the C library in C++03 mode.
+#if defined(_LIBCPP_CXX03_LANG) && __has_builtin(__builtin_va_copy)
+ __builtin_va_copy(ap_copy, ap);
+#else
+ va_copy(ap_copy, ap);
+#endif
+ int str_size = vsnprintf(*strp, buff_size, fmt, ap_copy);
+ va_end(ap_copy);
+
+ if ((size_t)str_size >= buff_size) {
+ if ((*strp = (char*)realloc(*strp, str_size + 1)) == NULL) {
+ return -1;
+ }
+ str_size = vsnprintf(*strp, str_size + 1, fmt, ap);
+ }
+ return str_size;
+}
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_IBM_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/locale_guard.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/locale_guard.h
new file mode 100644
index 00000000000000..2baacb51cd0655
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/locale_guard.h
@@ -0,0 +1,78 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_LOCALE_GUARD_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_LOCALE_GUARD_H
+
+#include <__config>
+#include <__locale> // for locale_t
+#include <clocale>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if !defined(_LIBCPP_LOCALE__L_EXTENSIONS)
+struct __libcpp_locale_guard {
+ _LIBCPP_HIDE_FROM_ABI __libcpp_locale_guard(locale_t& __loc) : __old_loc_(uselocale(__loc)) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~__libcpp_locale_guard() {
+ if (__old_loc_)
+ uselocale(__old_loc_);
+ }
+
+ locale_t __old_loc_;
+
+ __libcpp_locale_guard(__libcpp_locale_guard const&) = delete;
+ __libcpp_locale_guard& operator=(__libcpp_locale_guard const&) = delete;
+};
+#elif defined(_LIBCPP_MSVCRT_LIKE)
+struct __libcpp_locale_guard {
+ __libcpp_locale_guard(locale_t __l) : __status(_configthreadlocale(_ENABLE_PER_THREAD_LOCALE)) {
+ // Setting the locale can be expensive even when the locale given is
+ // already the current locale, so do an explicit check to see if the
+ // current locale is already the one we want.
+ const char* __lc = __setlocale(nullptr);
+ // If every category is the same, the locale string will simply be the
+ // locale name, otherwise it will be a semicolon-separated string listing
+ // each category. In the second case, we know at least one category won't
+ // be what we want, so we only have to check the first case.
+ if (std::strcmp(__l.__get_locale(), __lc) != 0) {
+ __locale_all = _strdup(__lc);
+ if (__locale_all == nullptr)
+ __throw_bad_alloc();
+ __setlocale(__l.__get_locale());
+ }
+ }
+ ~__libcpp_locale_guard() {
+ // The CRT documentation doesn't explicitly say, but setlocale() does the
+ // right thing when given a semicolon-separated list of locale settings
+ // for the different categories in the same format as returned by
+ // setlocale(LC_ALL, nullptr).
+ if (__locale_all != nullptr) {
+ __setlocale(__locale_all);
+ free(__locale_all);
+ }
+ _configthreadlocale(__status);
+ }
+ static const char* __setlocale(const char* __locale) {
+ const char* __new_locale = setlocale(LC_ALL, __locale);
+ if (__new_locale == nullptr)
+ __throw_bad_alloc();
+ return __new_locale;
+ }
+ int __status;
+ char* __locale_all = nullptr;
+};
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_LOCALE_GUARD_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/musl.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/musl.h
new file mode 100644
index 00000000000000..bf7b849d586342
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/musl.h
@@ -0,0 +1,31 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// This adds support for the extended locale functions that are currently
+// missing from the Musl C library.
+//
+// This only works when the specified locale is "C" or "POSIX", but that's
+// about as good as we can do without implementing full xlocale support
+// in Musl.
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_MUSL_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_MUSL_H
+
+#include <cstdlib>
+#include <cwchar>
+
+inline _LIBCPP_HIDE_FROM_ABI long long strtoll_l(const char* __nptr, char** __endptr, int __base, locale_t) {
+ return ::strtoll(__nptr, __endptr, __base);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI unsigned long long strtoull_l(const char* __nptr, char** __endptr, int __base, locale_t) {
+ return ::strtoull(__nptr, __endptr, __base);
+}
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_MUSL_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/newlib.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/newlib.h
new file mode 100644
index 00000000000000..a8c1cff16e6d80
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/newlib.h
@@ -0,0 +1,12 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_NEWLIB_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_NEWLIB_H
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_NEWLIB_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/openbsd.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/openbsd.h
new file mode 100644
index 00000000000000..0c05d6a0f78874
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/openbsd.h
@@ -0,0 +1,19 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_OPENBSD_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_OPENBSD_H
+
+#include <__support/xlocale/__strtonum_fallback.h>
+#include <clocale>
+#include <cstdlib>
+#include <ctype.h>
+#include <cwctype>
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_OPENBSD_H
diff --git a/libcxx/include/__cxx03/__locale_dir/locale_base_api/win32.h b/libcxx/include/__cxx03/__locale_dir/locale_base_api/win32.h
new file mode 100644
index 00000000000000..f66baffb692045
--- /dev/null
+++ b/libcxx/include/__cxx03/__locale_dir/locale_base_api/win32.h
@@ -0,0 +1,235 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_WIN32_H
+#define _LIBCPP___LOCALE_LOCALE_BASE_API_WIN32_H
+
+#include <__config>
+#include <cstddef>
+#include <locale.h> // _locale_t
+#include <stdio.h>
+#include <string>
+
+#define _X_ALL LC_ALL
+#define _X_COLLATE LC_COLLATE
+#define _X_CTYPE LC_CTYPE
+#define _X_MONETARY LC_MONETARY
+#define _X_NUMERIC LC_NUMERIC
+#define _X_TIME LC_TIME
+#define _X_MAX LC_MAX
+#define _X_MESSAGES 6
+#define _NCAT (_X_MESSAGES + 1)
+
+#define _CATMASK(n) ((1 << (n)) >> 1)
+#define _M_COLLATE _CATMASK(_X_COLLATE)
+#define _M_CTYPE _CATMASK(_X_CTYPE)
+#define _M_MONETARY _CATMASK(_X_MONETARY)
+#define _M_NUMERIC _CATMASK(_X_NUMERIC)
+#define _M_TIME _CATMASK(_X_TIME)
+#define _M_MESSAGES _CATMASK(_X_MESSAGES)
+#define _M_ALL (_CATMASK(_NCAT) - 1)
+
+#define LC_COLLATE_MASK _M_COLLATE
+#define LC_CTYPE_MASK _M_CTYPE
+#define LC_MONETARY_MASK _M_MONETARY
+#define LC_NUMERIC_MASK _M_NUMERIC
+#define LC_TIME_MASK _M_TIME
+#define LC_MESSAGES_MASK _M_MESSAGES
+#define LC_ALL_MASK \
+ (LC_COLLATE_MASK | LC_CTYPE_MASK | LC_MESSAGES_MASK | LC_MONETARY_MASK | LC_NUMERIC_MASK | LC_TIME_MASK)
+
+class __lconv_storage {
+public:
+ __lconv_storage(const lconv* __lc_input) {
+ __lc_ = *__lc_input;
+
+ __decimal_point_ = __lc_input->decimal_point;
+ __thousands_sep_ = __lc_input->thousands_sep;
+ __grouping_ = __lc_input->grouping;
+ __int_curr_symbol_ = __lc_input->int_curr_symbol;
+ __currency_symbol_ = __lc_input->currency_symbol;
+ __mon_decimal_point_ = __lc_input->mon_decimal_point;
+ __mon_thousands_sep_ = __lc_input->mon_thousands_sep;
+ __mon_grouping_ = __lc_input->mon_grouping;
+ __positive_sign_ = __lc_input->positive_sign;
+ __negative_sign_ = __lc_input->negative_sign;
+
+ __lc_.decimal_point = const_cast<char*>(__decimal_point_.c_str());
+ __lc_.thousands_sep = const_cast<char*>(__thousands_sep_.c_str());
+ __lc_.grouping = const_cast<char*>(__grouping_.c_str());
+ __lc_.int_curr_symbol = const_cast<char*>(__int_curr_symbol_.c_str());
+ __lc_.currency_symbol = const_cast<char*>(__currency_symbol_.c_str());
+ __lc_.mon_decimal_point = const_cast<char*>(__mon_decimal_point_.c_str());
+ __lc_.mon_thousands_sep = const_cast<char*>(__mon_thousands_sep_.c_str());
+ __lc_.mon_grouping = const_cast<char*>(__mon_grouping_.c_str());
+ __lc_.positive_sign = const_cast<char*>(__positive_sign_.c_str());
+ __lc_.negative_sign = const_cast<char*>(__negative_sign_.c_str());
+ }
+
+ lconv* __get() { return &__lc_; }
+
+private:
+ lconv __lc_;
+ std::string __decimal_point_;
+ std::string __thousands_sep_;
+ std::string __grouping_;
+ std::string __int_curr_symbol_;
+ std::string __currency_symbol_;
+ std::string __mon_decimal_point_;
+ std::string __mon_thousands_sep_;
+ std::string __mon_grouping_;
+ std::string __positive_sign_;
+ std::string __negative_sign_;
+};
+
+class locale_t {
+public:
+ locale_t() : __locale_(nullptr), __locale_str_(nullptr), __lc_(nullptr) {}
+ locale_t(std::nullptr_t) : __locale_(nullptr), __locale_str_(nullptr), __lc_(nullptr) {}
+ locale_t(_locale_t __xlocale, const char* __xlocale_str)
+ : __locale_(__xlocale), __locale_str_(__xlocale_str), __lc_(nullptr) {}
+ locale_t(const locale_t& __l) : __locale_(__l.__locale_), __locale_str_(__l.__locale_str_), __lc_(nullptr) {}
+
+ ~locale_t() { delete __lc_; }
+
+ locale_t& operator=(const locale_t& __l) {
+ __locale_ = __l.__locale_;
+ __locale_str_ = __l.__locale_str_;
+ // __lc_ not copied
+ return *this;
+ }
+
+ friend bool operator==(const locale_t& __left, const locale_t& __right) {
+ return __left.__locale_ == __right.__locale_;
+ }
+
+ friend bool operator==(const locale_t& __left, int __right) { return __left.__locale_ == nullptr && __right == 0; }
+
+ friend bool operator==(const locale_t& __left, long long __right) {
+ return __left.__locale_ == nullptr && __right == 0;
+ }
+
+ friend bool operator==(const locale_t& __left, std::nullptr_t) { return __left.__locale_ == nullptr; }
+
+ friend bool operator==(int __left, const locale_t& __right) { return __left == 0 && nullptr == __right.__locale_; }
+
+ friend bool operator==(std::nullptr_t, const locale_t& __right) { return nullptr == __right.__locale_; }
+
+ friend bool operator!=(const locale_t& __left, const locale_t& __right) { return !(__left == __right); }
+
+ friend bool operator!=(const locale_t& __left, int __right) { return !(__left == __right); }
+
+ friend bool operator!=(const locale_t& __left, long long __right) { return !(__left == __right); }
+
+ friend bool operator!=(const locale_t& __left, std::nullptr_t __right) { return !(__left == __right); }
+
+ friend bool operator!=(int __left, const locale_t& __right) { return !(__left == __right); }
+
+ friend bool operator!=(std::nullptr_t __left, const locale_t& __right) { return !(__left == __right); }
+
+ operator bool() const { return __locale_ != nullptr; }
+
+ const char* __get_locale() const { return __locale_str_; }
+
+ operator _locale_t() const { return __locale_; }
+
+ lconv* __store_lconv(const lconv* __input_lc) {
+ delete __lc_;
+ __lc_ = new __lconv_storage(__input_lc);
+ return __lc_->__get();
+ }
+
+private:
+ _locale_t __locale_;
+ const char* __locale_str_;
+ __lconv_storage* __lc_ = nullptr;
+};
+
+// Locale management functions
+#define freelocale _free_locale
+// FIXME: base currently unused. Needs manual work to construct the new locale
+locale_t newlocale(int __mask, const char* __locale, locale_t __base);
+// uselocale can't be implemented on Windows because Windows allows partial modification
+// of thread-local locale and so _get_current_locale() returns a copy while uselocale does
+// not create any copies.
+// We can still implement raii even without uselocale though.
+
+lconv* localeconv_l(locale_t& __loc);
+size_t mbrlen_l(const char* __restrict __s, size_t __n, mbstate_t* __restrict __ps, locale_t __loc);
+size_t mbsrtowcs_l(
+ wchar_t* __restrict __dst, const char** __restrict __src, size_t __len, mbstate_t* __restrict __ps, locale_t __loc);
+size_t wcrtomb_l(char* __restrict __s, wchar_t __wc, mbstate_t* __restrict __ps, locale_t __loc);
+size_t mbrtowc_l(
+ wchar_t* __restrict __pwc, const char* __restrict __s, size_t __n, mbstate_t* __restrict __ps, locale_t __loc);
+size_t mbsnrtowcs_l(wchar_t* __restrict __dst,
+ const char** __restrict __src,
+ size_t __nms,
+ size_t __len,
+ mbstate_t* __restrict __ps,
+ locale_t __loc);
+size_t wcsnrtombs_l(char* __restrict __dst,
+ const wchar_t** __restrict __src,
+ size_t __nwc,
+ size_t __len,
+ mbstate_t* __restrict __ps,
+ locale_t __loc);
+wint_t btowc_l(int __c, locale_t __loc);
+int wctob_l(wint_t __c, locale_t __loc);
+
+decltype(MB_CUR_MAX) MB_CUR_MAX_L(locale_t __l);
+
+// the *_l functions are prefixed on Windows, only available for msvcr80+, VS2005+
+#define mbtowc_l _mbtowc_l
+#define strtoll_l _strtoi64_l
+#define strtoull_l _strtoui64_l
+#define strtod_l _strtod_l
+#if defined(_LIBCPP_MSVCRT)
+# define strtof_l _strtof_l
+# define strtold_l _strtold_l
+#else
+_LIBCPP_EXPORTED_FROM_ABI float strtof_l(const char*, char**, locale_t);
+_LIBCPP_EXPORTED_FROM_ABI long double strtold_l(const char*, char**, locale_t);
+#endif
+inline _LIBCPP_HIDE_FROM_ABI int islower_l(int __c, _locale_t __loc) { return _islower_l((int)__c, __loc); }
+
+inline _LIBCPP_HIDE_FROM_ABI int isupper_l(int __c, _locale_t __loc) { return _isupper_l((int)__c, __loc); }
+
+#define isdigit_l _isdigit_l
+#define isxdigit_l _isxdigit_l
+#define strcoll_l _strcoll_l
+#define strxfrm_l _strxfrm_l
+#define wcscoll_l _wcscoll_l
+#define wcsxfrm_l _wcsxfrm_l
+#define toupper_l _toupper_l
+#define tolower_l _tolower_l
+#define iswspace_l _iswspace_l
+#define iswprint_l _iswprint_l
+#define iswcntrl_l _iswcntrl_l
+#define iswupper_l _iswupper_l
+#define iswlower_l _iswlower_l
+#define iswalpha_l _iswalpha_l
+#define iswdigit_l _iswdigit_l
+#define iswpunct_l _iswpunct_l
+#define iswxdigit_l _iswxdigit_l
+#define towupper_l _towupper_l
+#define towlower_l _towlower_l
+#if defined(__MINGW32__) && __MSVCRT_VERSION__ < 0x0800
+_LIBCPP_EXPORTED_FROM_ABI size_t strftime_l(char* ret, size_t n, const char* format, const struct tm* tm, locale_t loc);
+#else
+# define strftime_l _strftime_l
+#endif
+#define sscanf_l(__s, __l, __f, ...) _sscanf_l(__s, __f, __l, __VA_ARGS__)
+_LIBCPP_EXPORTED_FROM_ABI int snprintf_l(char* __ret, size_t __n, locale_t __loc, const char* __format, ...);
+_LIBCPP_EXPORTED_FROM_ABI int asprintf_l(char** __ret, locale_t __loc, const char* __format, ...);
+_LIBCPP_EXPORTED_FROM_ABI int vasprintf_l(char** __ret, locale_t __loc, const char* __format, va_list __ap);
+
+// not-so-pressing FIXME: use locale to determine blank characters
+inline int iswblank_l(wint_t __c, locale_t /*loc*/) { return (__c == L' ' || __c == L'\t'); }
+
+#endif // _LIBCPP___LOCALE_LOCALE_BASE_API_WIN32_H
diff --git a/libcxx/include/__cxx03/__math/abs.h b/libcxx/include/__cxx03/__math/abs.h
new file mode 100644
index 00000000000000..ab82a2800f53c9
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/abs.h
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_ABS_H
+#define _LIBCPP___MATH_ABS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// fabs
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float fabs(float __x) _NOEXCEPT { return __builtin_fabsf(__x); }
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double fabs(double __x) _NOEXCEPT {
+ return __builtin_fabs(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double fabs(long double __x) _NOEXCEPT {
+ return __builtin_fabsl(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double fabs(_A1 __x) _NOEXCEPT {
+ return __builtin_fabs((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_ABS_H
diff --git a/libcxx/include/__cxx03/__math/copysign.h b/libcxx/include/__cxx03/__math/copysign.h
new file mode 100644
index 00000000000000..b38690bb581a11
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/copysign.h
@@ -0,0 +1,45 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_COPYSIGN_H
+#define _LIBCPP___MATH_COPYSIGN_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/promote.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// copysign
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float copysign(float __x, float __y) _NOEXCEPT {
+ return ::__builtin_copysignf(__x, __y);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double copysign(long double __x, long double __y) _NOEXCEPT {
+ return ::__builtin_copysignl(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type copysign(_A1 __x, _A2 __y) _NOEXCEPT {
+ return ::__builtin_copysign(__x, __y);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_COPYSIGN_H
diff --git a/libcxx/include/__cxx03/__math/error_functions.h b/libcxx/include/__cxx03/__math/error_functions.h
new file mode 100644
index 00000000000000..6b528bb290001a
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/error_functions.h
@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_ERROR_FUNCTIONS_H
+#define _LIBCPP___MATH_ERROR_FUNCTIONS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// erf
+
+inline _LIBCPP_HIDE_FROM_ABI float erf(float __x) _NOEXCEPT { return __builtin_erff(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double erf(double __x) _NOEXCEPT {
+ return __builtin_erf(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double erf(long double __x) _NOEXCEPT { return __builtin_erfl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double erf(_A1 __x) _NOEXCEPT {
+ return __builtin_erf((double)__x);
+}
+
+// erfc
+
+inline _LIBCPP_HIDE_FROM_ABI float erfc(float __x) _NOEXCEPT { return __builtin_erfcf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double erfc(double __x) _NOEXCEPT {
+ return __builtin_erfc(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double erfc(long double __x) _NOEXCEPT { return __builtin_erfcl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double erfc(_A1 __x) _NOEXCEPT {
+ return __builtin_erfc((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_ERROR_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__math/exponential_functions.h b/libcxx/include/__cxx03/__math/exponential_functions.h
new file mode 100644
index 00000000000000..109c3349970f67
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/exponential_functions.h
@@ -0,0 +1,171 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_EXPONENTIAL_FUNCTIONS_H
+#define _LIBCPP___MATH_EXPONENTIAL_FUNCTIONS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// exp
+
+inline _LIBCPP_HIDE_FROM_ABI float exp(float __x) _NOEXCEPT { return __builtin_expf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double exp(double __x) _NOEXCEPT {
+ return __builtin_exp(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double exp(long double __x) _NOEXCEPT { return __builtin_expl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double exp(_A1 __x) _NOEXCEPT {
+ return __builtin_exp((double)__x);
+}
+
+// frexp
+
+inline _LIBCPP_HIDE_FROM_ABI float frexp(float __x, int* __e) _NOEXCEPT { return __builtin_frexpf(__x, __e); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double frexp(double __x, int* __e) _NOEXCEPT {
+ return __builtin_frexp(__x, __e);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double frexp(long double __x, int* __e) _NOEXCEPT {
+ return __builtin_frexpl(__x, __e);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double frexp(_A1 __x, int* __e) _NOEXCEPT {
+ return __builtin_frexp((double)__x, __e);
+}
+
+// ldexp
+
+inline _LIBCPP_HIDE_FROM_ABI float ldexp(float __x, int __e) _NOEXCEPT { return __builtin_ldexpf(__x, __e); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double ldexp(double __x, int __e) _NOEXCEPT {
+ return __builtin_ldexp(__x, __e);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double ldexp(long double __x, int __e) _NOEXCEPT {
+ return __builtin_ldexpl(__x, __e);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double ldexp(_A1 __x, int __e) _NOEXCEPT {
+ return __builtin_ldexp((double)__x, __e);
+}
+
+// exp2
+
+inline _LIBCPP_HIDE_FROM_ABI float exp2(float __x) _NOEXCEPT { return __builtin_exp2f(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double exp2(double __x) _NOEXCEPT {
+ return __builtin_exp2(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double exp2(long double __x) _NOEXCEPT { return __builtin_exp2l(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double exp2(_A1 __x) _NOEXCEPT {
+ return __builtin_exp2((double)__x);
+}
+
+// expm1
+
+inline _LIBCPP_HIDE_FROM_ABI float expm1(float __x) _NOEXCEPT { return __builtin_expm1f(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double expm1(double __x) _NOEXCEPT {
+ return __builtin_expm1(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double expm1(long double __x) _NOEXCEPT { return __builtin_expm1l(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double expm1(_A1 __x) _NOEXCEPT {
+ return __builtin_expm1((double)__x);
+}
+
+// scalbln
+
+inline _LIBCPP_HIDE_FROM_ABI float scalbln(float __x, long __y) _NOEXCEPT { return __builtin_scalblnf(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double scalbln(double __x, long __y) _NOEXCEPT {
+ return __builtin_scalbln(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double scalbln(long double __x, long __y) _NOEXCEPT {
+ return __builtin_scalblnl(__x, __y);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double scalbln(_A1 __x, long __y) _NOEXCEPT {
+ return __builtin_scalbln((double)__x, __y);
+}
+
+// scalbn
+
+inline _LIBCPP_HIDE_FROM_ABI float scalbn(float __x, int __y) _NOEXCEPT { return __builtin_scalbnf(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double scalbn(double __x, int __y) _NOEXCEPT {
+ return __builtin_scalbn(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double scalbn(long double __x, int __y) _NOEXCEPT {
+ return __builtin_scalbnl(__x, __y);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double scalbn(_A1 __x, int __y) _NOEXCEPT {
+ return __builtin_scalbn((double)__x, __y);
+}
+
+// pow
+
+inline _LIBCPP_HIDE_FROM_ABI float pow(float __x, float __y) _NOEXCEPT { return __builtin_powf(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double pow(double __x, double __y) _NOEXCEPT {
+ return __builtin_pow(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double pow(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_powl(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type pow(_A1 __x, _A2 __y) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::pow((__result_type)__x, (__result_type)__y);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_EXPONENTIAL_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__math/fdim.h b/libcxx/include/__cxx03/__math/fdim.h
new file mode 100644
index 00000000000000..dc1b4ecc07dce4
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/fdim.h
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_FDIM_H
+#define _LIBCPP___MATH_FDIM_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+inline _LIBCPP_HIDE_FROM_ABI float fdim(float __x, float __y) _NOEXCEPT { return __builtin_fdimf(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double fdim(double __x, double __y) _NOEXCEPT {
+ return __builtin_fdim(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double fdim(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_fdiml(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type fdim(_A1 __x, _A2 __y) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::fdim((__result_type)__x, (__result_type)__y);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_FDIM_H
diff --git a/libcxx/include/__cxx03/__math/fma.h b/libcxx/include/__cxx03/__math/fma.h
new file mode 100644
index 00000000000000..6ba7a5a2d26d60
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/fma.h
@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_FMA_H
+#define _LIBCPP___MATH_FMA_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+inline _LIBCPP_HIDE_FROM_ABI float fma(float __x, float __y, float __z) _NOEXCEPT {
+ return __builtin_fmaf(__x, __y, __z);
+}
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double fma(double __x, double __y, double __z) _NOEXCEPT {
+ return __builtin_fma(__x, __y, __z);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double fma(long double __x, long double __y, long double __z) _NOEXCEPT {
+ return __builtin_fmal(__x, __y, __z);
+}
+
+template <class _A1,
+ class _A2,
+ class _A3,
+ __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value && is_arithmetic<_A3>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2, _A3>::type fma(_A1 __x, _A2 __y, _A3 __z) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2, _A3>::type;
+ static_assert(
+ !(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value && _IsSame<_A3, __result_type>::value),
+ "");
+ return __builtin_fma((__result_type)__x, (__result_type)__y, (__result_type)__z);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_FMA_H
diff --git a/libcxx/include/__cxx03/__math/gamma.h b/libcxx/include/__cxx03/__math/gamma.h
new file mode 100644
index 00000000000000..693e111a84e99d
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/gamma.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_GAMMA_H
+#define _LIBCPP___MATH_GAMMA_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// lgamma
+
+inline _LIBCPP_HIDE_FROM_ABI float lgamma(float __x) _NOEXCEPT { return __builtin_lgammaf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double lgamma(double __x) _NOEXCEPT {
+ return __builtin_lgamma(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double lgamma(long double __x) _NOEXCEPT { return __builtin_lgammal(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double lgamma(_A1 __x) _NOEXCEPT {
+ return __builtin_lgamma((double)__x);
+}
+
+// nan
+
+// tgamma
+
+inline _LIBCPP_HIDE_FROM_ABI float tgamma(float __x) _NOEXCEPT { return __builtin_tgammaf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double tgamma(double __x) _NOEXCEPT {
+ return __builtin_tgamma(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double tgamma(long double __x) _NOEXCEPT { return __builtin_tgammal(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double tgamma(_A1 __x) _NOEXCEPT {
+ return __builtin_tgamma((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_GAMMA_H
diff --git a/libcxx/include/__cxx03/__math/hyperbolic_functions.h b/libcxx/include/__cxx03/__math/hyperbolic_functions.h
new file mode 100644
index 00000000000000..78832bae70c9d1
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/hyperbolic_functions.h
@@ -0,0 +1,76 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_HYPERBOLIC_FUNCTIONS_H
+#define _LIBCPP___MATH_HYPERBOLIC_FUNCTIONS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// cosh
+
+inline _LIBCPP_HIDE_FROM_ABI float cosh(float __x) _NOEXCEPT { return __builtin_coshf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double cosh(double __x) _NOEXCEPT {
+ return __builtin_cosh(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double cosh(long double __x) _NOEXCEPT { return __builtin_coshl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double cosh(_A1 __x) _NOEXCEPT {
+ return __builtin_cosh((double)__x);
+}
+
+// sinh
+
+inline _LIBCPP_HIDE_FROM_ABI float sinh(float __x) _NOEXCEPT { return __builtin_sinhf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double sinh(double __x) _NOEXCEPT {
+ return __builtin_sinh(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double sinh(long double __x) _NOEXCEPT { return __builtin_sinhl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double sinh(_A1 __x) _NOEXCEPT {
+ return __builtin_sinh((double)__x);
+}
+
+// tanh
+
+inline _LIBCPP_HIDE_FROM_ABI float tanh(float __x) _NOEXCEPT { return __builtin_tanhf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double tanh(double __x) _NOEXCEPT {
+ return __builtin_tanh(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double tanh(long double __x) _NOEXCEPT { return __builtin_tanhl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double tanh(_A1 __x) _NOEXCEPT {
+ return __builtin_tanh((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_HYPERBOLIC_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__math/hypot.h b/libcxx/include/__cxx03/__math/hypot.h
new file mode 100644
index 00000000000000..b992163711010a
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/hypot.h
@@ -0,0 +1,109 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_HYPOT_H
+#define _LIBCPP___MATH_HYPOT_H
+
+#include <__algorithm/max.h>
+#include <__config>
+#include <__math/abs.h>
+#include <__math/exponential_functions.h>
+#include <__math/roots.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+#include <__utility/pair.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+inline _LIBCPP_HIDE_FROM_ABI float hypot(float __x, float __y) _NOEXCEPT { return __builtin_hypotf(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double hypot(double __x, double __y) _NOEXCEPT {
+ return __builtin_hypot(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double hypot(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_hypotl(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type hypot(_A1 __x, _A2 __y) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::hypot((__result_type)__x, (__result_type)__y);
+}
+
+#if _LIBCPP_STD_VER >= 17
+// Computes the three-dimensional hypotenuse: `std::hypot(x,y,z)`.
+// The naive implementation might over-/underflow which is why this implementation is more involved:
+// If the square of an argument might run into issues, we scale the arguments appropriately.
+// See https://github.com/llvm/llvm-project/issues/92782 for a detailed discussion and summary.
+template <class _Real>
+_LIBCPP_HIDE_FROM_ABI _Real __hypot(_Real __x, _Real __y, _Real __z) {
+ // Factors needed to determine if over-/underflow might happen
+ constexpr int __exp = std::numeric_limits<_Real>::max_exponent / 2;
+ const _Real __overflow_threshold = __math::ldexp(_Real(1), __exp);
+ const _Real __overflow_scale = __math::ldexp(_Real(1), -(__exp + 20));
+
+ // Scale arguments depending on their size
+ const _Real __max_abs = std::max(__math::fabs(__x), std::max(__math::fabs(__y), __math::fabs(__z)));
+ _Real __scale;
+ if (__max_abs > __overflow_threshold) { // x*x + y*y + z*z might overflow
+ __scale = __overflow_scale;
+ } else if (__max_abs < 1 / __overflow_threshold) { // x*x + y*y + z*z might underflow
+ __scale = 1 / __overflow_scale;
+ } else {
+ __scale = 1;
+ }
+ __x *= __scale;
+ __y *= __scale;
+ __z *= __scale;
+
+ // Compute hypot of scaled arguments and undo scaling
+ return __math::sqrt(__x * __x + __y * __y + __z * __z) / __scale;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI float hypot(float __x, float __y, float __z) { return __math::__hypot(__x, __y, __z); }
+
+inline _LIBCPP_HIDE_FROM_ABI double hypot(double __x, double __y, double __z) { return __math::__hypot(__x, __y, __z); }
+
+inline _LIBCPP_HIDE_FROM_ABI long double hypot(long double __x, long double __y, long double __z) {
+ return __math::__hypot(__x, __y, __z);
+}
+
+template <class _A1,
+ class _A2,
+ class _A3,
+ std::enable_if_t< is_arithmetic_v<_A1> && is_arithmetic_v<_A2> && is_arithmetic_v<_A3>, int> = 0 >
+_LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2, _A3>::type hypot(_A1 __x, _A2 __y, _A3 __z) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2, _A3>::type;
+ static_assert(!(
+ std::is_same_v<_A1, __result_type> && std::is_same_v<_A2, __result_type> && std::is_same_v<_A3, __result_type>));
+ return __math::__hypot(
+ static_cast<__result_type>(__x), static_cast<__result_type>(__y), static_cast<__result_type>(__z));
+}
+#endif
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MATH_HYPOT_H
diff --git a/libcxx/include/__cxx03/__math/inverse_hyperbolic_functions.h b/libcxx/include/__cxx03/__math/inverse_hyperbolic_functions.h
new file mode 100644
index 00000000000000..4660a58e4eba02
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/inverse_hyperbolic_functions.h
@@ -0,0 +1,76 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_INVERSE_HYPERBOLIC_FUNCTIONS_H
+#define _LIBCPP___MATH_INVERSE_HYPERBOLIC_FUNCTIONS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// acosh
+
+inline _LIBCPP_HIDE_FROM_ABI float acosh(float __x) _NOEXCEPT { return __builtin_acoshf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double acosh(double __x) _NOEXCEPT {
+ return __builtin_acosh(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double acosh(long double __x) _NOEXCEPT { return __builtin_acoshl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double acosh(_A1 __x) _NOEXCEPT {
+ return __builtin_acosh((double)__x);
+}
+
+// asinh
+
+inline _LIBCPP_HIDE_FROM_ABI float asinh(float __x) _NOEXCEPT { return __builtin_asinhf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double asinh(double __x) _NOEXCEPT {
+ return __builtin_asinh(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double asinh(long double __x) _NOEXCEPT { return __builtin_asinhl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double asinh(_A1 __x) _NOEXCEPT {
+ return __builtin_asinh((double)__x);
+}
+
+// atanh
+
+inline _LIBCPP_HIDE_FROM_ABI float atanh(float __x) _NOEXCEPT { return __builtin_atanhf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double atanh(double __x) _NOEXCEPT {
+ return __builtin_atanh(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double atanh(long double __x) _NOEXCEPT { return __builtin_atanhl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double atanh(_A1 __x) _NOEXCEPT {
+ return __builtin_atanh((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_INVERSE_HYPERBOLIC_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__math/inverse_trigonometric_functions.h b/libcxx/include/__cxx03/__math/inverse_trigonometric_functions.h
new file mode 100644
index 00000000000000..cd98b46a6aab8b
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/inverse_trigonometric_functions.h
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_INVERSE_TRIGONOMETRIC_FUNCTIONS_H
+#define _LIBCPP___MATH_INVERSE_TRIGONOMETRIC_FUNCTIONS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// acos
+
+inline _LIBCPP_HIDE_FROM_ABI float acos(float __x) _NOEXCEPT { return __builtin_acosf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double acos(double __x) _NOEXCEPT {
+ return __builtin_acos(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double acos(long double __x) _NOEXCEPT { return __builtin_acosl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double acos(_A1 __x) _NOEXCEPT {
+ return __builtin_acos((double)__x);
+}
+
+// asin
+
+inline _LIBCPP_HIDE_FROM_ABI float asin(float __x) _NOEXCEPT { return __builtin_asinf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double asin(double __x) _NOEXCEPT {
+ return __builtin_asin(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double asin(long double __x) _NOEXCEPT { return __builtin_asinl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double asin(_A1 __x) _NOEXCEPT {
+ return __builtin_asin((double)__x);
+}
+
+// atan
+
+inline _LIBCPP_HIDE_FROM_ABI float atan(float __x) _NOEXCEPT { return __builtin_atanf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double atan(double __x) _NOEXCEPT {
+ return __builtin_atan(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double atan(long double __x) _NOEXCEPT { return __builtin_atanl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double atan(_A1 __x) _NOEXCEPT {
+ return __builtin_atan((double)__x);
+}
+
+// atan2
+
+inline _LIBCPP_HIDE_FROM_ABI float atan2(float __y, float __x) _NOEXCEPT { return __builtin_atan2f(__y, __x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double atan2(double __x, double __y) _NOEXCEPT {
+ return __builtin_atan2(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double atan2(long double __y, long double __x) _NOEXCEPT {
+ return __builtin_atan2l(__y, __x);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type atan2(_A1 __y, _A2 __x) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::atan2((__result_type)__y, (__result_type)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_INVERSE_TRIGONOMETRIC_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__math/logarithms.h b/libcxx/include/__cxx03/__math/logarithms.h
new file mode 100644
index 00000000000000..5f5f943977a508
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/logarithms.h
@@ -0,0 +1,124 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_LOGARITHMS_H
+#define _LIBCPP___MATH_LOGARITHMS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// log
+
+inline _LIBCPP_HIDE_FROM_ABI float log(float __x) _NOEXCEPT { return __builtin_logf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double log(double __x) _NOEXCEPT {
+ return __builtin_log(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double log(long double __x) _NOEXCEPT { return __builtin_logl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double log(_A1 __x) _NOEXCEPT {
+ return __builtin_log((double)__x);
+}
+
+// log10
+
+inline _LIBCPP_HIDE_FROM_ABI float log10(float __x) _NOEXCEPT { return __builtin_log10f(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double log10(double __x) _NOEXCEPT {
+ return __builtin_log10(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double log10(long double __x) _NOEXCEPT { return __builtin_log10l(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double log10(_A1 __x) _NOEXCEPT {
+ return __builtin_log10((double)__x);
+}
+
+// ilogb
+
+inline _LIBCPP_HIDE_FROM_ABI int ilogb(float __x) _NOEXCEPT { return __builtin_ilogbf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double ilogb(double __x) _NOEXCEPT {
+ return __builtin_ilogb(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int ilogb(long double __x) _NOEXCEPT { return __builtin_ilogbl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI int ilogb(_A1 __x) _NOEXCEPT {
+ return __builtin_ilogb((double)__x);
+}
+
+// log1p
+
+inline _LIBCPP_HIDE_FROM_ABI float log1p(float __x) _NOEXCEPT { return __builtin_log1pf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double log1p(double __x) _NOEXCEPT {
+ return __builtin_log1p(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double log1p(long double __x) _NOEXCEPT { return __builtin_log1pl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double log1p(_A1 __x) _NOEXCEPT {
+ return __builtin_log1p((double)__x);
+}
+
+// log2
+
+inline _LIBCPP_HIDE_FROM_ABI float log2(float __x) _NOEXCEPT { return __builtin_log2f(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double log2(double __x) _NOEXCEPT {
+ return __builtin_log2(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double log2(long double __x) _NOEXCEPT { return __builtin_log2l(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double log2(_A1 __x) _NOEXCEPT {
+ return __builtin_log2((double)__x);
+}
+
+// logb
+
+inline _LIBCPP_HIDE_FROM_ABI float logb(float __x) _NOEXCEPT { return __builtin_logbf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double logb(double __x) _NOEXCEPT {
+ return __builtin_logb(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double logb(long double __x) _NOEXCEPT { return __builtin_logbl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double logb(_A1 __x) _NOEXCEPT {
+ return __builtin_logb((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_LOGARITHMS_H
diff --git a/libcxx/include/__cxx03/__math/min_max.h b/libcxx/include/__cxx03/__math/min_max.h
new file mode 100644
index 00000000000000..27997b44910a12
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/min_max.h
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_MIN_MAX_H
+#define _LIBCPP___MATH_MIN_MAX_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// fmax
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float fmax(float __x, float __y) _NOEXCEPT {
+ return __builtin_fmaxf(__x, __y);
+}
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double fmax(double __x, double __y) _NOEXCEPT {
+ return __builtin_fmax(__x, __y);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double fmax(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_fmaxl(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type fmax(_A1 __x, _A2 __y) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::fmax((__result_type)__x, (__result_type)__y);
+}
+
+// fmin
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float fmin(float __x, float __y) _NOEXCEPT {
+ return __builtin_fminf(__x, __y);
+}
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double fmin(double __x, double __y) _NOEXCEPT {
+ return __builtin_fmin(__x, __y);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double fmin(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_fminl(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type fmin(_A1 __x, _A2 __y) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::fmin((__result_type)__x, (__result_type)__y);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_MIN_MAX_H
diff --git a/libcxx/include/__cxx03/__math/modulo.h b/libcxx/include/__cxx03/__math/modulo.h
new file mode 100644
index 00000000000000..c8ea506f37d755
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/modulo.h
@@ -0,0 +1,63 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_MODULO_H
+#define _LIBCPP___MATH_MODULO_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// fmod
+
+inline _LIBCPP_HIDE_FROM_ABI float fmod(float __x, float __y) _NOEXCEPT { return __builtin_fmodf(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double fmod(double __x, double __y) _NOEXCEPT {
+ return __builtin_fmod(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double fmod(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_fmodl(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type fmod(_A1 __x, _A2 __y) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::fmod((__result_type)__x, (__result_type)__y);
+}
+
+// modf
+
+inline _LIBCPP_HIDE_FROM_ABI float modf(float __x, float* __y) _NOEXCEPT { return __builtin_modff(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double modf(double __x, double* __y) _NOEXCEPT {
+ return __builtin_modf(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double modf(long double __x, long double* __y) _NOEXCEPT {
+ return __builtin_modfl(__x, __y);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_MODULO_H
diff --git a/libcxx/include/__cxx03/__math/remainder.h b/libcxx/include/__cxx03/__math/remainder.h
new file mode 100644
index 00000000000000..0fbf0b8ef97b9e
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/remainder.h
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_REMAINDER_H
+#define _LIBCPP___MATH_REMAINDER_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// remainder
+
+inline _LIBCPP_HIDE_FROM_ABI float remainder(float __x, float __y) _NOEXCEPT { return __builtin_remainderf(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double remainder(double __x, double __y) _NOEXCEPT {
+ return __builtin_remainder(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double remainder(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_remainderl(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type remainder(_A1 __x, _A2 __y) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::remainder((__result_type)__x, (__result_type)__y);
+}
+
+// remquo
+
+inline _LIBCPP_HIDE_FROM_ABI float remquo(float __x, float __y, int* __z) _NOEXCEPT {
+ return __builtin_remquof(__x, __y, __z);
+}
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double remquo(double __x, double __y, int* __z) _NOEXCEPT {
+ return __builtin_remquo(__x, __y, __z);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double remquo(long double __x, long double __y, int* __z) _NOEXCEPT {
+ return __builtin_remquol(__x, __y, __z);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type remquo(_A1 __x, _A2 __y, int* __z) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::remquo((__result_type)__x, (__result_type)__y, __z);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_REMAINDER_H
diff --git a/libcxx/include/__cxx03/__math/roots.h b/libcxx/include/__cxx03/__math/roots.h
new file mode 100644
index 00000000000000..359fd747cfbef3
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/roots.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_ROOTS_H
+#define _LIBCPP___MATH_ROOTS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// sqrt
+
+inline _LIBCPP_HIDE_FROM_ABI float sqrt(float __x) _NOEXCEPT { return __builtin_sqrtf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double sqrt(double __x) _NOEXCEPT {
+ return __builtin_sqrt(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double sqrt(long double __x) _NOEXCEPT { return __builtin_sqrtl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double sqrt(_A1 __x) _NOEXCEPT {
+ return __builtin_sqrt((double)__x);
+}
+
+// cbrt
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float cbrt(float __x) _NOEXCEPT { return __builtin_cbrtf(__x); }
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double cbrt(double __x) _NOEXCEPT {
+ return __builtin_cbrt(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double cbrt(long double __x) _NOEXCEPT {
+ return __builtin_cbrtl(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double cbrt(_A1 __x) _NOEXCEPT {
+ return __builtin_cbrt((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_ROOTS_H
diff --git a/libcxx/include/__cxx03/__math/rounding_functions.h b/libcxx/include/__cxx03/__math/rounding_functions.h
new file mode 100644
index 00000000000000..f7246ba7fed0d6
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/rounding_functions.h
@@ -0,0 +1,245 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_ROUNDING_FUNCTIONS_H
+#define _LIBCPP___MATH_ROUNDING_FUNCTIONS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// ceil
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float ceil(float __x) _NOEXCEPT { return __builtin_ceilf(__x); }
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double ceil(double __x) _NOEXCEPT {
+ return __builtin_ceil(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double ceil(long double __x) _NOEXCEPT {
+ return __builtin_ceill(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double ceil(_A1 __x) _NOEXCEPT {
+ return __builtin_ceil((double)__x);
+}
+
+// floor
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float floor(float __x) _NOEXCEPT { return __builtin_floorf(__x); }
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double floor(double __x) _NOEXCEPT {
+ return __builtin_floor(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double floor(long double __x) _NOEXCEPT {
+ return __builtin_floorl(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double floor(_A1 __x) _NOEXCEPT {
+ return __builtin_floor((double)__x);
+}
+
+// llrint
+
+inline _LIBCPP_HIDE_FROM_ABI long long llrint(float __x) _NOEXCEPT { return __builtin_llrintf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI long long llrint(double __x) _NOEXCEPT {
+ return __builtin_llrint(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long long llrint(long double __x) _NOEXCEPT { return __builtin_llrintl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI long long llrint(_A1 __x) _NOEXCEPT {
+ return __builtin_llrint((double)__x);
+}
+
+// llround
+
+inline _LIBCPP_HIDE_FROM_ABI long long llround(float __x) _NOEXCEPT { return __builtin_llroundf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI long long llround(double __x) _NOEXCEPT {
+ return __builtin_llround(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long long llround(long double __x) _NOEXCEPT { return __builtin_llroundl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI long long llround(_A1 __x) _NOEXCEPT {
+ return __builtin_llround((double)__x);
+}
+
+// lrint
+
+inline _LIBCPP_HIDE_FROM_ABI long lrint(float __x) _NOEXCEPT { return __builtin_lrintf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI long lrint(double __x) _NOEXCEPT {
+ return __builtin_lrint(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long lrint(long double __x) _NOEXCEPT { return __builtin_lrintl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI long lrint(_A1 __x) _NOEXCEPT {
+ return __builtin_lrint((double)__x);
+}
+
+// lround
+
+inline _LIBCPP_HIDE_FROM_ABI long lround(float __x) _NOEXCEPT { return __builtin_lroundf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI long lround(double __x) _NOEXCEPT {
+ return __builtin_lround(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long lround(long double __x) _NOEXCEPT { return __builtin_lroundl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI long lround(_A1 __x) _NOEXCEPT {
+ return __builtin_lround((double)__x);
+}
+
+// nearbyint
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float nearbyint(float __x) _NOEXCEPT {
+ return __builtin_nearbyintf(__x);
+}
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double nearbyint(double __x) _NOEXCEPT {
+ return __builtin_nearbyint(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double nearbyint(long double __x) _NOEXCEPT {
+ return __builtin_nearbyintl(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double nearbyint(_A1 __x) _NOEXCEPT {
+ return __builtin_nearbyint((double)__x);
+}
+
+// nextafter
+
+inline _LIBCPP_HIDE_FROM_ABI float nextafter(float __x, float __y) _NOEXCEPT { return __builtin_nextafterf(__x, __y); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double nextafter(double __x, double __y) _NOEXCEPT {
+ return __builtin_nextafter(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double nextafter(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_nextafterl(__x, __y);
+}
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __promote<_A1, _A2>::type nextafter(_A1 __x, _A2 __y) _NOEXCEPT {
+ using __result_type = typename __promote<_A1, _A2>::type;
+ static_assert(!(_IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value), "");
+ return __math::nextafter((__result_type)__x, (__result_type)__y);
+}
+
+// nexttoward
+
+inline _LIBCPP_HIDE_FROM_ABI float nexttoward(float __x, long double __y) _NOEXCEPT {
+ return __builtin_nexttowardf(__x, __y);
+}
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double nexttoward(double __x, long double __y) _NOEXCEPT {
+ return __builtin_nexttoward(__x, __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double nexttoward(long double __x, long double __y) _NOEXCEPT {
+ return __builtin_nexttowardl(__x, __y);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double nexttoward(_A1 __x, long double __y) _NOEXCEPT {
+ return __builtin_nexttoward((double)__x, __y);
+}
+
+// rint
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float rint(float __x) _NOEXCEPT { return __builtin_rintf(__x); }
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double rint(double __x) _NOEXCEPT {
+ return __builtin_rint(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double rint(long double __x) _NOEXCEPT {
+ return __builtin_rintl(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double rint(_A1 __x) _NOEXCEPT {
+ return __builtin_rint((double)__x);
+}
+
+// round
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float round(float __x) _NOEXCEPT { return __builtin_round(__x); }
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double round(double __x) _NOEXCEPT {
+ return __builtin_round(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double round(long double __x) _NOEXCEPT {
+ return __builtin_roundl(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double round(_A1 __x) _NOEXCEPT {
+ return __builtin_round((double)__x);
+}
+
+// trunc
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float trunc(float __x) _NOEXCEPT { return __builtin_trunc(__x); }
+
+template <class = int>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI double trunc(double __x) _NOEXCEPT {
+ return __builtin_trunc(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double trunc(long double __x) _NOEXCEPT {
+ return __builtin_truncl(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double trunc(_A1 __x) _NOEXCEPT {
+ return __builtin_trunc((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_ROUNDING_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__math/special_functions.h b/libcxx/include/__cxx03/__math/special_functions.h
new file mode 100644
index 00000000000000..0b1c753a659ade
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/special_functions.h
@@ -0,0 +1,84 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_SPECIAL_FUNCTIONS_H
+#define _LIBCPP___MATH_SPECIAL_FUNCTIONS_H
+
+#include <__config>
+#include <__math/copysign.h>
+#include <__math/traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Real>
+_LIBCPP_HIDE_FROM_ABI _Real __hermite(unsigned __n, _Real __x) {
+ // The Hermite polynomial H_n(x).
+ // The implementation is based on the recurrence formula: H_{n+1}(x) = 2x H_n(x) - 2n H_{n-1}.
+ // Press, William H., et al. Numerical recipes 3rd edition: The art of scientific computing.
+ // Cambridge university press, 2007, p. 183.
+
+ // NOLINTBEGIN(readability-identifier-naming)
+ if (__math::isnan(__x))
+ return __x;
+
+ _Real __H_0{1};
+ if (__n == 0)
+ return __H_0;
+
+ _Real __H_n_prev = __H_0;
+ _Real __H_n = 2 * __x;
+ for (unsigned __i = 1; __i < __n; ++__i) {
+ _Real __H_n_next = 2 * (__x * __H_n - __i * __H_n_prev);
+ __H_n_prev = __H_n;
+ __H_n = __H_n_next;
+ }
+
+ if (!__math::isfinite(__H_n)) {
+ // Overflow occured. Two possible cases:
+ // n is odd: return infinity of the same sign as x.
+ // n is even: return +Inf
+ _Real __inf = std::numeric_limits<_Real>::infinity();
+ return (__n & 1) ? __math::copysign(__inf, __x) : __inf;
+ }
+ return __H_n;
+ // NOLINTEND(readability-identifier-naming)
+}
+
+inline _LIBCPP_HIDE_FROM_ABI double hermite(unsigned __n, double __x) { return std::__hermite(__n, __x); }
+
+inline _LIBCPP_HIDE_FROM_ABI float hermite(unsigned __n, float __x) {
+ // use double internally -- float is too prone to overflow!
+ return static_cast<float>(std::hermite(__n, static_cast<double>(__x)));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double hermite(unsigned __n, long double __x) { return std::__hermite(__n, __x); }
+
+inline _LIBCPP_HIDE_FROM_ABI float hermitef(unsigned __n, float __x) { return std::hermite(__n, __x); }
+
+inline _LIBCPP_HIDE_FROM_ABI long double hermitel(unsigned __n, long double __x) { return std::hermite(__n, __x); }
+
+template <class _Integer, std::enable_if_t<std::is_integral_v<_Integer>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI double hermite(unsigned __n, _Integer __x) {
+ return std::hermite(__n, static_cast<double>(__x));
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_SPECIAL_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__math/traits.h b/libcxx/include/__cxx03/__math/traits.h
new file mode 100644
index 00000000000000..27ec52ecef022e
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/traits.h
@@ -0,0 +1,188 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_TRAITS_H
+#define _LIBCPP___MATH_TRAITS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/promote.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// signbit
+
+template <class _A1, __enable_if_t<is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool signbit(_A1 __x) _NOEXCEPT {
+ return __builtin_signbit(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value && is_signed<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool signbit(_A1 __x) _NOEXCEPT {
+ return __x < 0;
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value && !is_signed<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool signbit(_A1) _NOEXCEPT {
+ return false;
+}
+
+// isfinite
+
+template <class _A1, __enable_if_t<is_arithmetic<_A1>::value && numeric_limits<_A1>::has_infinity, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isfinite(_A1 __x) _NOEXCEPT {
+ return __builtin_isfinite((typename __promote<_A1>::type)__x);
+}
+
+template <class _A1, __enable_if_t<is_arithmetic<_A1>::value && !numeric_limits<_A1>::has_infinity, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isfinite(_A1) _NOEXCEPT {
+ return true;
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isfinite(float __x) _NOEXCEPT {
+ return __builtin_isfinite(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isfinite(double __x) _NOEXCEPT {
+ return __builtin_isfinite(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isfinite(long double __x) _NOEXCEPT {
+ return __builtin_isfinite(__x);
+}
+
+// isinf
+
+template <class _A1, __enable_if_t<is_arithmetic<_A1>::value && numeric_limits<_A1>::has_infinity, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isinf(_A1 __x) _NOEXCEPT {
+ return __builtin_isinf((typename __promote<_A1>::type)__x);
+}
+
+template <class _A1, __enable_if_t<is_arithmetic<_A1>::value && !numeric_limits<_A1>::has_infinity, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isinf(_A1) _NOEXCEPT {
+ return false;
+}
+
+#ifdef _LIBCPP_PREFERRED_OVERLOAD
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isinf(float __x) _NOEXCEPT {
+ return __builtin_isinf(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD bool
+isinf(double __x) _NOEXCEPT {
+ return __builtin_isinf(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isinf(long double __x) _NOEXCEPT {
+ return __builtin_isinf(__x);
+}
+#endif
+
+// isnan
+
+template <class _A1, __enable_if_t<is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnan(_A1 __x) _NOEXCEPT {
+ return __builtin_isnan(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnan(_A1) _NOEXCEPT {
+ return false;
+}
+
+#ifdef _LIBCPP_PREFERRED_OVERLOAD
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnan(float __x) _NOEXCEPT {
+ return __builtin_isnan(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD bool
+isnan(double __x) _NOEXCEPT {
+ return __builtin_isnan(__x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnan(long double __x) _NOEXCEPT {
+ return __builtin_isnan(__x);
+}
+#endif
+
+// isnormal
+
+template <class _A1, __enable_if_t<is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnormal(_A1 __x) _NOEXCEPT {
+ return __builtin_isnormal(__x);
+}
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnormal(_A1 __x) _NOEXCEPT {
+ return __x != 0;
+}
+
+// isgreater
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool isgreater(_A1 __x, _A2 __y) _NOEXCEPT {
+ using type = typename __promote<_A1, _A2>::type;
+ return __builtin_isgreater((type)__x, (type)__y);
+}
+
+// isgreaterequal
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool isgreaterequal(_A1 __x, _A2 __y) _NOEXCEPT {
+ using type = typename __promote<_A1, _A2>::type;
+ return __builtin_isgreaterequal((type)__x, (type)__y);
+}
+
+// isless
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool isless(_A1 __x, _A2 __y) _NOEXCEPT {
+ using type = typename __promote<_A1, _A2>::type;
+ return __builtin_isless((type)__x, (type)__y);
+}
+
+// islessequal
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool islessequal(_A1 __x, _A2 __y) _NOEXCEPT {
+ using type = typename __promote<_A1, _A2>::type;
+ return __builtin_islessequal((type)__x, (type)__y);
+}
+
+// islessgreater
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool islessgreater(_A1 __x, _A2 __y) _NOEXCEPT {
+ using type = typename __promote<_A1, _A2>::type;
+ return __builtin_islessgreater((type)__x, (type)__y);
+}
+
+// isunordered
+
+template <class _A1, class _A2, __enable_if_t<is_arithmetic<_A1>::value && is_arithmetic<_A2>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI bool isunordered(_A1 __x, _A2 __y) _NOEXCEPT {
+ using type = typename __promote<_A1, _A2>::type;
+ return __builtin_isunordered((type)__x, (type)__y);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_TRAITS_H
diff --git a/libcxx/include/__cxx03/__math/trigonometric_functions.h b/libcxx/include/__cxx03/__math/trigonometric_functions.h
new file mode 100644
index 00000000000000..0ad91c76316091
--- /dev/null
+++ b/libcxx/include/__cxx03/__math/trigonometric_functions.h
@@ -0,0 +1,76 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MATH_TRIGONOMETRIC_FUNCTIONS_H
+#define _LIBCPP___MATH_TRIGONOMETRIC_FUNCTIONS_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// cos
+
+inline _LIBCPP_HIDE_FROM_ABI float cos(float __x) _NOEXCEPT { return __builtin_cosf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double cos(double __x) _NOEXCEPT {
+ return __builtin_cos(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double cos(long double __x) _NOEXCEPT { return __builtin_cosl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double cos(_A1 __x) _NOEXCEPT {
+ return __builtin_cos((double)__x);
+}
+
+// sin
+
+inline _LIBCPP_HIDE_FROM_ABI float sin(float __x) _NOEXCEPT { return __builtin_sinf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double sin(double __x) _NOEXCEPT {
+ return __builtin_sin(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double sin(long double __x) _NOEXCEPT { return __builtin_sinl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double sin(_A1 __x) _NOEXCEPT {
+ return __builtin_sin((double)__x);
+}
+
+// tan
+
+inline _LIBCPP_HIDE_FROM_ABI float tan(float __x) _NOEXCEPT { return __builtin_tanf(__x); }
+
+template <class = int>
+_LIBCPP_HIDE_FROM_ABI double tan(double __x) _NOEXCEPT {
+ return __builtin_tan(__x);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double tan(long double __x) _NOEXCEPT { return __builtin_tanl(__x); }
+
+template <class _A1, __enable_if_t<is_integral<_A1>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double tan(_A1 __x) _NOEXCEPT {
+ return __builtin_tan((double)__x);
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MATH_TRIGONOMETRIC_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__mbstate_t.h b/libcxx/include/__cxx03/__mbstate_t.h
new file mode 100644
index 00000000000000..bfa6d617e2b8f5
--- /dev/null
+++ b/libcxx/include/__cxx03/__mbstate_t.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MBSTATE_T_H
+#define _LIBCPP___MBSTATE_T_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// The goal of this header is to provide mbstate_t without requiring all of
+// <uchar.h> or <wchar.h>. It's also used by the libc++ versions of <uchar.h>
+// and <wchar.h> to get mbstate_t when the C library doesn't provide <uchar.h>
+// or <wchar.h>, hence the #include_next of those headers instead of #include.
+// (e.g. if <wchar.h> isn't present in the C library, the libc++ <wchar.h>
+// will include this header. This header needs to not turn around and cyclically
+// include <wchar.h>, but fall through to <uchar.h>.)
+//
+// This does not define std::mbstate_t -- this only brings in the declaration
+// in the global namespace.
+
+// We define this here to support older versions of glibc <wchar.h> that do
+// not define this for clang. This is also set in libc++'s <wchar.h> header,
+// and we need to do so here too to avoid a different function signature given
+// a different include order.
+#ifdef __cplusplus
+# define __CORRECT_ISO_CPP_WCHAR_H_PROTO
+#endif
+
+#if defined(_LIBCPP_HAS_MUSL_LIBC)
+# define __NEED_mbstate_t
+# include <bits/alltypes.h>
+# undef __NEED_mbstate_t
+#elif __has_include(<bits/types/mbstate_t.h>)
+# include <bits/types/mbstate_t.h> // works on most Unixes
+#elif __has_include(<sys/_types/_mbstate_t.h>)
+# include <sys/_types/_mbstate_t.h> // works on Darwin
+#elif !defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS) && __has_include_next(<wchar.h>)
+# include_next <wchar.h> // fall back to the C standard provider of mbstate_t
+#elif __has_include_next(<uchar.h>)
+# include_next <uchar.h> // <uchar.h> is also required to make mbstate_t visible
+#else
+# error "We don't know how to get the definition of mbstate_t without <wchar.h> on your platform."
+#endif
+
+#endif // _LIBCPP___MBSTATE_T_H
diff --git a/libcxx/include/__cxx03/__mdspan/default_accessor.h b/libcxx/include/__cxx03/__mdspan/default_accessor.h
new file mode 100644
index 00000000000000..1cc5f15545fc8c
--- /dev/null
+++ b/libcxx/include/__cxx03/__mdspan/default_accessor.h
@@ -0,0 +1,66 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MDSPAN_DEFAULT_ACCESSOR_H
+#define _LIBCPP___MDSPAN_DEFAULT_ACCESSOR_H
+
+#include <__config>
+#include <__type_traits/is_abstract.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/remove_const.h>
+#include <cinttypes>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _ElementType>
+struct default_accessor {
+ static_assert(!is_array_v<_ElementType>, "default_accessor: template argument may not be an array type");
+ static_assert(!is_abstract_v<_ElementType>, "default_accessor: template argument may not be an abstract class");
+
+ using offset_policy = default_accessor;
+ using element_type = _ElementType;
+ using reference = _ElementType&;
+ using data_handle_type = _ElementType*;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr default_accessor() noexcept = default;
+ template <class _OtherElementType>
+ requires(is_convertible_v<_OtherElementType (*)[], element_type (*)[]>)
+ _LIBCPP_HIDE_FROM_ABI constexpr default_accessor(default_accessor<_OtherElementType>) noexcept {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference access(data_handle_type __p, size_t __i) const noexcept { return __p[__i]; }
+ _LIBCPP_HIDE_FROM_ABI constexpr data_handle_type offset(data_handle_type __p, size_t __i) const noexcept {
+ return __p + __i;
+ }
+};
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MDSPAN_DEFAULT_ACCESSOR_H
diff --git a/libcxx/include/__cxx03/__mdspan/extents.h b/libcxx/include/__cxx03/__mdspan/extents.h
new file mode 100644
index 00000000000000..95082ef3d11ac9
--- /dev/null
+++ b/libcxx/include/__cxx03/__mdspan/extents.h
@@ -0,0 +1,532 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MDSPAN_EXTENTS_H
+#define _LIBCPP___MDSPAN_EXTENTS_H
+
+#include <__assert>
+#include <__config>
+#include <__type_traits/common_type.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/make_unsigned.h>
+#include <__utility/integer_sequence.h>
+#include <__utility/unreachable.h>
+#include <array>
+#include <cinttypes>
+#include <concepts>
+#include <cstddef>
+#include <limits>
+#include <span>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+namespace __mdspan_detail {
+
+// ------------------------------------------------------------------
+// ------------ __static_array --------------------------------------
+// ------------------------------------------------------------------
+// array like class which provides an array of static values with get
+template <class _Tp, _Tp... _Values>
+struct __static_array {
+ static constexpr array<_Tp, sizeof...(_Values)> __array = {_Values...};
+
+public:
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t __size() { return sizeof...(_Values); }
+ _LIBCPP_HIDE_FROM_ABI static constexpr _Tp __get(size_t __index) noexcept { return __array[__index]; }
+
+ template <size_t _Index>
+ _LIBCPP_HIDE_FROM_ABI static constexpr _Tp __get() {
+ return __get(_Index);
+ }
+};
+
+// ------------------------------------------------------------------
+// ------------ __possibly_empty_array -----------------------------
+// ------------------------------------------------------------------
+
+// array like class which provides get function and operator [], and
+// has a specialization for the size 0 case.
+// This is needed to make the __maybe_static_array be truly empty, for
+// all static values.
+
+template <class _Tp, size_t _Size>
+struct __possibly_empty_array {
+ _Tp __vals_[_Size];
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& operator[](size_t __index) { return __vals_[__index]; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& operator[](size_t __index) const { return __vals_[__index]; }
+};
+
+template <class _Tp>
+struct __possibly_empty_array<_Tp, 0> {
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& operator[](size_t) { __libcpp_unreachable(); }
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& operator[](size_t) const { __libcpp_unreachable(); }
+};
+
+// ------------------------------------------------------------------
+// ------------ static_partial_sums ---------------------------------
+// ------------------------------------------------------------------
+
+// Provides a compile time partial sum one can index into
+
+template <size_t... _Values>
+struct __static_partial_sums {
+ _LIBCPP_HIDE_FROM_ABI static constexpr array<size_t, sizeof...(_Values)> __static_partial_sums_impl() {
+ array<size_t, sizeof...(_Values)> __values{_Values...};
+ array<size_t, sizeof...(_Values)> __partial_sums{{}};
+ size_t __running_sum = 0;
+ for (int __i = 0; __i != sizeof...(_Values); ++__i) {
+ __partial_sums[__i] = __running_sum;
+ __running_sum += __values[__i];
+ }
+ return __partial_sums;
+ }
+ static constexpr array<size_t, sizeof...(_Values)> __result{__static_partial_sums_impl()};
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t __get(size_t __index) { return __result[__index]; }
+};
+
+// ------------------------------------------------------------------
+// ------------ __maybe_static_array --------------------------------
+// ------------------------------------------------------------------
+
+// array like class which has a mix of static and runtime values but
+// only stores the runtime values.
+// The type of the static and the runtime values can be different.
+// The position of a dynamic value is indicated through a tag value.
+template <class _TDynamic, class _TStatic, _TStatic _DynTag, _TStatic... _Values>
+struct __maybe_static_array {
+ static_assert(is_convertible<_TStatic, _TDynamic>::value,
+ "__maybe_static_array: _TStatic must be convertible to _TDynamic");
+ static_assert(is_convertible<_TDynamic, _TStatic>::value,
+ "__maybe_static_array: _TDynamic must be convertible to _TStatic");
+
+private:
+ // Static values member
+ static constexpr size_t __size_ = sizeof...(_Values);
+ static constexpr size_t __size_dynamic_ = ((_Values == _DynTag) + ... + 0);
+ using _StaticValues = __static_array<_TStatic, _Values...>;
+ using _DynamicValues = __possibly_empty_array<_TDynamic, __size_dynamic_>;
+
+ // Dynamic values member
+ _LIBCPP_NO_UNIQUE_ADDRESS _DynamicValues __dyn_vals_;
+
+ // static mapping of indices to the position in the dynamic values array
+ using _DynamicIdxMap = __static_partial_sums<static_cast<size_t>(_Values == _DynTag)...>;
+
+ template <size_t... _Indices>
+ _LIBCPP_HIDE_FROM_ABI static constexpr _DynamicValues __zeros(index_sequence<_Indices...>) noexcept {
+ return _DynamicValues{((void)_Indices, 0)...};
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr __maybe_static_array() noexcept
+ : __dyn_vals_{__zeros(make_index_sequence<__size_dynamic_>())} {}
+
+ // constructors from dynamic values only -- this covers the case for rank() == 0
+ template <class... _DynVals>
+ requires(sizeof...(_DynVals) == __size_dynamic_)
+ _LIBCPP_HIDE_FROM_ABI constexpr __maybe_static_array(_DynVals... __vals)
+ : __dyn_vals_{static_cast<_TDynamic>(__vals)...} {}
+
+ template <class _Tp, size_t _Size >
+ requires(_Size == __size_dynamic_)
+ _LIBCPP_HIDE_FROM_ABI constexpr __maybe_static_array([[maybe_unused]] const span<_Tp, _Size>& __vals) {
+ if constexpr (_Size > 0) {
+ for (size_t __i = 0; __i < _Size; __i++)
+ __dyn_vals_[__i] = static_cast<_TDynamic>(__vals[__i]);
+ }
+ }
+
+ // constructors from all values -- here rank will be greater than 0
+ template <class... _DynVals>
+ requires(sizeof...(_DynVals) != __size_dynamic_)
+ _LIBCPP_HIDE_FROM_ABI constexpr __maybe_static_array(_DynVals... __vals) {
+ static_assert(sizeof...(_DynVals) == __size_, "Invalid number of values.");
+ _TDynamic __values[__size_] = {static_cast<_TDynamic>(__vals)...};
+ for (size_t __i = 0; __i < __size_; __i++) {
+ _TStatic __static_val = _StaticValues::__get(__i);
+ if (__static_val == _DynTag) {
+ __dyn_vals_[_DynamicIdxMap::__get(__i)] = __values[__i];
+ } else
+ // Not catching this could lead to out of bounds errors later
+ // e.g. using my_mdspan_t = mdspan<int, extents<int, 10>>; my_mdspan_t = m(new int[5], 5);
+ // Right-hand-side construction looks ok with allocation and size matching,
+ // but since (potentially elsewhere defined) my_mdspan_t has static size m now thinks its range is 10 not 5
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __values[__i] == static_cast<_TDynamic>(__static_val),
+ "extents construction: mismatch of provided arguments with static extents.");
+ }
+ }
+
+ template <class _Tp, size_t _Size>
+ requires(_Size != __size_dynamic_)
+ _LIBCPP_HIDE_FROM_ABI constexpr __maybe_static_array(const span<_Tp, _Size>& __vals) {
+ static_assert(_Size == __size_ || __size_ == dynamic_extent);
+ for (size_t __i = 0; __i < __size_; __i++) {
+ _TStatic __static_val = _StaticValues::__get(__i);
+ if (__static_val == _DynTag) {
+ __dyn_vals_[_DynamicIdxMap::__get(__i)] = static_cast<_TDynamic>(__vals[__i]);
+ } else
+ // Not catching this could lead to out of bounds errors later
+ // e.g. using my_mdspan_t = mdspan<int, extents<int, 10>>; my_mdspan_t = m(new int[N], span<int,1>(&N));
+ // Right-hand-side construction looks ok with allocation and size matching,
+ // but since (potentially elsewhere defined) my_mdspan_t has static size m now thinks its range is 10 not N
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ static_cast<_TDynamic>(__vals[__i]) == static_cast<_TDynamic>(__static_val),
+ "extents construction: mismatch of provided arguments with static extents.");
+ }
+ }
+
+ // access functions
+ _LIBCPP_HIDE_FROM_ABI static constexpr _TStatic __static_value(size_t __i) noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < __size_, "extents access: index must be less than rank");
+ return _StaticValues::__get(__i);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _TDynamic __value(size_t __i) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < __size_, "extents access: index must be less than rank");
+ _TStatic __static_val = _StaticValues::__get(__i);
+ return __static_val == _DynTag ? __dyn_vals_[_DynamicIdxMap::__get(__i)] : static_cast<_TDynamic>(__static_val);
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr _TDynamic operator[](size_t __i) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < __size_, "extents access: index must be less than rank");
+ return __value(__i);
+ }
+
+ // observers
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t __size() { return __size_; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t __size_dynamic() { return __size_dynamic_; }
+};
+
+// Function to check whether a value is representable as another type
+// value must be a positive integer otherwise returns false
+// if _From is not an integral, we just check positivity
+template <integral _To, class _From>
+ requires(integral<_From>)
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_representable_as(_From __value) {
+ using _To_u = make_unsigned_t<_To>;
+ using _From_u = make_unsigned_t<_From>;
+ if constexpr (is_signed_v<_From>) {
+ if (__value < 0)
+ return false;
+ }
+ if constexpr (static_cast<_To_u>(numeric_limits<_To>::max()) >= static_cast<_From_u>(numeric_limits<_From>::max())) {
+ return true;
+ } else {
+ return static_cast<_To_u>(numeric_limits<_To>::max()) >= static_cast<_From_u>(__value);
+ }
+}
+
+template <integral _To, class _From>
+ requires(!integral<_From>)
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_representable_as(_From __value) {
+ if constexpr (is_signed_v<_To>) {
+ if (static_cast<_To>(__value) < 0)
+ return false;
+ }
+ return true;
+}
+
+template <integral _To, class... _From>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __are_representable_as(_From... __values) {
+ return (__mdspan_detail::__is_representable_as<_To>(__values) && ... && true);
+}
+
+template <integral _To, class _From, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __are_representable_as(span<_From, _Size> __values) {
+ for (size_t __i = 0; __i < _Size; __i++)
+ if (!__mdspan_detail::__is_representable_as<_To>(__values[__i]))
+ return false;
+ return true;
+}
+
+} // namespace __mdspan_detail
+
+// ------------------------------------------------------------------
+// ------------ extents ---------------------------------------------
+// ------------------------------------------------------------------
+
+// Class to describe the extents of a multi dimensional array.
+// Used by mdspan, mdarray and layout mappings.
+// See ISO C++ standard [mdspan.extents]
+
+template <class _IndexType, size_t... _Extents>
+class extents {
+public:
+ // typedefs for integral types used
+ using index_type = _IndexType;
+ using size_type = make_unsigned_t<index_type>;
+ using rank_type = size_t;
+
+ static_assert(is_integral<index_type>::value && !is_same<index_type, bool>::value,
+ "extents::index_type must be a signed or unsigned integer type");
+ static_assert(((__mdspan_detail::__is_representable_as<index_type>(_Extents) || (_Extents == dynamic_extent)) && ...),
+ "extents ctor: arguments must be representable as index_type and nonnegative");
+
+private:
+ static constexpr rank_type __rank_ = sizeof...(_Extents);
+ static constexpr rank_type __rank_dynamic_ = ((_Extents == dynamic_extent) + ... + 0);
+
+ // internal storage type using __maybe_static_array
+ using _Values = __mdspan_detail::__maybe_static_array<_IndexType, size_t, dynamic_extent, _Extents...>;
+ [[no_unique_address]] _Values __vals_;
+
+public:
+ // [mdspan.extents.obs], observers of multidimensional index space
+ _LIBCPP_HIDE_FROM_ABI static constexpr rank_type rank() noexcept { return __rank_; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr rank_type rank_dynamic() noexcept { return __rank_dynamic_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type extent(rank_type __r) const noexcept { return __vals_.__value(__r); }
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t static_extent(rank_type __r) noexcept {
+ return _Values::__static_value(__r);
+ }
+
+ // [mdspan.extents.cons], constructors
+ _LIBCPP_HIDE_FROM_ABI constexpr extents() noexcept = default;
+
+ // Construction from just dynamic or all values.
+ // Precondition check is deferred to __maybe_static_array constructor
+ template <class... _OtherIndexTypes>
+ requires((is_convertible_v<_OtherIndexTypes, index_type> && ...) &&
+ (is_nothrow_constructible_v<index_type, _OtherIndexTypes> && ...) &&
+ (sizeof...(_OtherIndexTypes) == __rank_ || sizeof...(_OtherIndexTypes) == __rank_dynamic_))
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit extents(_OtherIndexTypes... __dynvals) noexcept
+ : __vals_(static_cast<index_type>(__dynvals)...) {
+ // Not catching this could lead to out of bounds errors later
+ // e.g. mdspan m(ptr, dextents<char, 1>(200u)); leads to an extent of -56 on m
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__mdspan_detail::__are_representable_as<index_type>(__dynvals...),
+ "extents ctor: arguments must be representable as index_type and nonnegative");
+ }
+
+ template <class _OtherIndexType, size_t _Size>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&> &&
+ (_Size == __rank_ || _Size == __rank_dynamic_))
+ explicit(_Size != __rank_dynamic_)
+ _LIBCPP_HIDE_FROM_ABI constexpr extents(const array<_OtherIndexType, _Size>& __exts) noexcept
+ : __vals_(span(__exts)) {
+ // Not catching this could lead to out of bounds errors later
+ // e.g. mdspan m(ptr, dextents<char, 1>(array<unsigned,1>(200))); leads to an extent of -56 on m
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__mdspan_detail::__are_representable_as<index_type>(span(__exts)),
+ "extents ctor: arguments must be representable as index_type and nonnegative");
+ }
+
+ template <class _OtherIndexType, size_t _Size>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&> &&
+ (_Size == __rank_ || _Size == __rank_dynamic_))
+ explicit(_Size != __rank_dynamic_)
+ _LIBCPP_HIDE_FROM_ABI constexpr extents(const span<_OtherIndexType, _Size>& __exts) noexcept
+ : __vals_(__exts) {
+ // Not catching this could lead to out of bounds errors later
+ // e.g. array a{200u}; mdspan<int, dextents<char,1>> m(ptr, extents(span<unsigned,1>(a))); leads to an extent of -56
+ // on m
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__mdspan_detail::__are_representable_as<index_type>(__exts),
+ "extents ctor: arguments must be representable as index_type and nonnegative");
+ }
+
+private:
+ // Function to construct extents storage from other extents.
+ template <size_t _DynCount, size_t _Idx, class _OtherExtents, class... _DynamicValues>
+ requires(_Idx < __rank_)
+ _LIBCPP_HIDE_FROM_ABI constexpr _Values __construct_vals_from_extents(
+ integral_constant<size_t, _DynCount>,
+ integral_constant<size_t, _Idx>,
+ const _OtherExtents& __exts,
+ _DynamicValues... __dynamic_values) noexcept {
+ if constexpr (static_extent(_Idx) == dynamic_extent)
+ return __construct_vals_from_extents(
+ integral_constant<size_t, _DynCount + 1>(),
+ integral_constant<size_t, _Idx + 1>(),
+ __exts,
+ __dynamic_values...,
+ __exts.extent(_Idx));
+ else
+ return __construct_vals_from_extents(
+ integral_constant<size_t, _DynCount>(), integral_constant<size_t, _Idx + 1>(), __exts, __dynamic_values...);
+ }
+
+ template <size_t _DynCount, size_t _Idx, class _OtherExtents, class... _DynamicValues>
+ requires((_Idx == __rank_) && (_DynCount == __rank_dynamic_))
+ _LIBCPP_HIDE_FROM_ABI constexpr _Values __construct_vals_from_extents(
+ integral_constant<size_t, _DynCount>,
+ integral_constant<size_t, _Idx>,
+ const _OtherExtents&,
+ _DynamicValues... __dynamic_values) noexcept {
+ return _Values{static_cast<index_type>(__dynamic_values)...};
+ }
+
+public:
+ // Converting constructor from other extents specializations
+ template <class _OtherIndexType, size_t... _OtherExtents>
+ requires((sizeof...(_OtherExtents) == sizeof...(_Extents)) &&
+ ((_OtherExtents == dynamic_extent || _Extents == dynamic_extent || _OtherExtents == _Extents) && ...))
+ explicit((((_Extents != dynamic_extent) && (_OtherExtents == dynamic_extent)) || ...) ||
+ (static_cast<make_unsigned_t<index_type>>(numeric_limits<index_type>::max()) <
+ static_cast<make_unsigned_t<_OtherIndexType>>(numeric_limits<_OtherIndexType>::max())))
+ _LIBCPP_HIDE_FROM_ABI constexpr extents(const extents<_OtherIndexType, _OtherExtents...>& __other) noexcept
+ : __vals_(
+ __construct_vals_from_extents(integral_constant<size_t, 0>(), integral_constant<size_t, 0>(), __other)) {
+ if constexpr (rank() > 0) {
+ for (size_t __r = 0; __r < rank(); __r++) {
+ if constexpr (static_cast<make_unsigned_t<index_type>>(numeric_limits<index_type>::max()) <
+ static_cast<make_unsigned_t<_OtherIndexType>>(numeric_limits<_OtherIndexType>::max())) {
+ // Not catching this could lead to out of bounds errors later
+ // e.g. dextents<char,1>> e(dextents<unsigned,1>(200)) leads to an extent of -56 on e
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __mdspan_detail::__is_representable_as<index_type>(__other.extent(__r)),
+ "extents ctor: arguments must be representable as index_type and nonnegative");
+ }
+ // Not catching this could lead to out of bounds errors later
+ // e.g. mdspan<int, extents<int, 10>> m = mdspan<int, dextents<int, 1>>(new int[5], 5);
+ // Right-hand-side construction was ok, but m now thinks its range is 10 not 5
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ (_Values::__static_value(__r) == dynamic_extent) ||
+ (static_cast<index_type>(__other.extent(__r)) == static_cast<index_type>(_Values::__static_value(__r))),
+ "extents construction: mismatch of provided arguments with static extents.");
+ }
+ }
+ }
+
+ // Comparison operator
+ template <class _OtherIndexType, size_t... _OtherExtents>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool
+ operator==(const extents& __lhs, const extents<_OtherIndexType, _OtherExtents...>& __rhs) noexcept {
+ if constexpr (rank() != sizeof...(_OtherExtents)) {
+ return false;
+ } else {
+ for (rank_type __r = 0; __r < __rank_; __r++) {
+ // avoid warning when comparing signed and unsigner integers and pick the wider of two types
+ using _CommonType = common_type_t<index_type, _OtherIndexType>;
+ if (static_cast<_CommonType>(__lhs.extent(__r)) != static_cast<_CommonType>(__rhs.extent(__r))) {
+ return false;
+ }
+ }
+ }
+ return true;
+ }
+};
+
+// Recursive helper classes to implement dextents alias for extents
+namespace __mdspan_detail {
+
+template <class _IndexType, size_t _Rank, class _Extents = extents<_IndexType>>
+struct __make_dextents;
+
+template <class _IndexType, size_t _Rank, size_t... _ExtentsPack>
+struct __make_dextents< _IndexType, _Rank, extents<_IndexType, _ExtentsPack...>> {
+ using type =
+ typename __make_dextents< _IndexType, _Rank - 1, extents<_IndexType, dynamic_extent, _ExtentsPack...>>::type;
+};
+
+template <class _IndexType, size_t... _ExtentsPack>
+struct __make_dextents< _IndexType, 0, extents<_IndexType, _ExtentsPack...>> {
+ using type = extents<_IndexType, _ExtentsPack...>;
+};
+
+} // end namespace __mdspan_detail
+
+// [mdspan.extents.dextents], alias template
+template <class _IndexType, size_t _Rank>
+using dextents = typename __mdspan_detail::__make_dextents<_IndexType, _Rank>::type;
+
+# if _LIBCPP_STD_VER >= 26
+// [mdspan.extents.dims], alias template `dims`
+template <size_t _Rank, class _IndexType = size_t>
+using dims = dextents<_IndexType, _Rank>;
+# endif
+
+// Deduction guide for extents
+# if _LIBCPP_STD_VER >= 26
+template <class... _IndexTypes>
+ requires(is_convertible_v<_IndexTypes, size_t> && ...)
+explicit extents(_IndexTypes...) -> extents<size_t, __maybe_static_ext<_IndexTypes>...>;
+# else
+template <class... _IndexTypes>
+ requires(is_convertible_v<_IndexTypes, size_t> && ...)
+explicit extents(_IndexTypes...) -> extents<size_t, size_t(((void)sizeof(_IndexTypes), dynamic_extent))...>;
+# endif
+
+namespace __mdspan_detail {
+
+// Helper type traits for identifying a class as extents.
+template <class _Tp>
+struct __is_extents : false_type {};
+
+template <class _IndexType, size_t... _ExtentsPack>
+struct __is_extents<extents<_IndexType, _ExtentsPack...>> : true_type {};
+
+template <class _Tp>
+inline constexpr bool __is_extents_v = __is_extents<_Tp>::value;
+
+// Function to check whether a set of indices are a multidimensional
+// index into extents. This is a word of power in the C++ standard
+// requiring that the indices are larger than 0 and smaller than
+// the respective extents.
+
+template <integral _IndexType, class _From>
+ requires(integral<_From>)
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_index_in_extent(_IndexType __extent, _From __value) {
+ if constexpr (is_signed_v<_From>) {
+ if (__value < 0)
+ return false;
+ }
+ using _Tp = common_type_t<_IndexType, _From>;
+ return static_cast<_Tp>(__value) < static_cast<_Tp>(__extent);
+}
+
+template <integral _IndexType, class _From>
+ requires(!integral<_From>)
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_index_in_extent(_IndexType __extent, _From __value) {
+ if constexpr (is_signed_v<_IndexType>) {
+ if (static_cast<_IndexType>(__value) < 0)
+ return false;
+ }
+ return static_cast<_IndexType>(__value) < __extent;
+}
+
+template <size_t... _Idxs, class _Extents, class... _From>
+_LIBCPP_HIDE_FROM_ABI constexpr bool
+__is_multidimensional_index_in_impl(index_sequence<_Idxs...>, const _Extents& __ext, _From... __values) {
+ return (__mdspan_detail::__is_index_in_extent(__ext.extent(_Idxs), __values) && ...);
+}
+
+template <class _Extents, class... _From>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __is_multidimensional_index_in(const _Extents& __ext, _From... __values) {
+ return __mdspan_detail::__is_multidimensional_index_in_impl(
+ make_index_sequence<_Extents::rank()>(), __ext, __values...);
+}
+
+} // namespace __mdspan_detail
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MDSPAN_EXTENTS_H
diff --git a/libcxx/include/__cxx03/__mdspan/layout_left.h b/libcxx/include/__cxx03/__mdspan/layout_left.h
new file mode 100644
index 00000000000000..d058cbccffd96d
--- /dev/null
+++ b/libcxx/include/__cxx03/__mdspan/layout_left.h
@@ -0,0 +1,204 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MDSPAN_LAYOUT_LEFT_H
+#define _LIBCPP___MDSPAN_LAYOUT_LEFT_H
+
+#include <__assert>
+#include <__config>
+#include <__fwd/mdspan.h>
+#include <__mdspan/extents.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__utility/integer_sequence.h>
+#include <array>
+#include <cinttypes>
+#include <cstddef>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Extents>
+class layout_left::mapping {
+public:
+ static_assert(__mdspan_detail::__is_extents<_Extents>::value,
+ "layout_left::mapping template argument must be a specialization of extents.");
+
+ using extents_type = _Extents;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using layout_type = layout_left;
+
+private:
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __required_span_size_is_representable(const extents_type& __ext) {
+ if constexpr (extents_type::rank() == 0)
+ return true;
+
+ index_type __prod = __ext.extent(0);
+ for (rank_type __r = 1; __r < extents_type::rank(); __r++) {
+ bool __overflowed = __builtin_mul_overflow(__prod, __ext.extent(__r), &__prod);
+ if (__overflowed)
+ return false;
+ }
+ return true;
+ }
+
+ static_assert(extents_type::rank_dynamic() > 0 || __required_span_size_is_representable(extents_type()),
+ "layout_left::mapping product of static extents must be representable as index_type.");
+
+public:
+ // [mdspan.layout.left.cons], constructors
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping() noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping(const mapping&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping(const extents_type& __ext) noexcept : __extents_(__ext) {
+ // not catching this could lead to out-of-bounds access later when used inside mdspan
+ // mapping<dextents<char, 2>> map(dextents<char, 2>(40,40)); map(10, 3) == -126
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __required_span_size_is_representable(__ext),
+ "layout_left::mapping extents ctor: product of extents must be representable as index_type.");
+ }
+
+ template <class _OtherExtents>
+ requires(is_constructible_v<extents_type, _OtherExtents>)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_OtherExtents, extents_type>)
+ mapping(const mapping<_OtherExtents>& __other) noexcept
+ : __extents_(__other.extents()) {
+ // not catching this could lead to out-of-bounds access later when used inside mdspan
+ // mapping<dextents<char, 2>> map(mapping<dextents<int, 2>>(dextents<int, 2>(40,40))); map(10, 3) == -126
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __mdspan_detail::__is_representable_as<index_type>(__other.required_span_size()),
+ "layout_left::mapping converting ctor: other.required_span_size() must be representable as index_type.");
+ }
+
+ template <class _OtherExtents>
+ requires(is_constructible_v<extents_type, _OtherExtents> && _OtherExtents::rank() <= 1)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_OtherExtents, extents_type>)
+ mapping(const layout_right::mapping<_OtherExtents>& __other) noexcept
+ : __extents_(__other.extents()) {
+ // not catching this could lead to out-of-bounds access later when used inside mdspan
+ // Note: since this is constraint to rank 1, extents itself would catch the invalid conversion first
+ // and thus this assertion should never be triggered, but keeping it here for consistency
+ // layout_left::mapping<dextents<char, 1>> map(
+ // layout_right::mapping<dextents<unsigned, 1>>(dextents<unsigned, 1>(200))); map.extents().extent(0) ==
+ // -56
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __mdspan_detail::__is_representable_as<index_type>(__other.required_span_size()),
+ "layout_left::mapping converting ctor: other.required_span_size() must be representable as index_type.");
+ }
+
+ template <class _OtherExtents>
+ requires(is_constructible_v<extents_type, _OtherExtents>)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(extents_type::rank() > 0)
+ mapping(const layout_stride::mapping<_OtherExtents>& __other) noexcept
+ : __extents_(__other.extents()) {
+ if constexpr (extents_type::rank() > 0) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ ([&]() {
+ using _CommonType = common_type_t<typename extents_type::index_type, typename _OtherExtents::index_type>;
+ for (rank_type __r = 0; __r < extents_type::rank(); __r++)
+ if (static_cast<_CommonType>(stride(__r)) != static_cast<_CommonType>(__other.stride(__r)))
+ return false;
+ return true;
+ }()),
+ "layout_left::mapping from layout_stride ctor: strides are not compatible with layout_left.");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __mdspan_detail::__is_representable_as<index_type>(__other.required_span_size()),
+ "layout_left::mapping from layout_stride ctor: other.required_span_size() must be representable as "
+ "index_type.");
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping& operator=(const mapping&) noexcept = default;
+
+ // [mdspan.layout.left.obs], observers
+ _LIBCPP_HIDE_FROM_ABI constexpr const extents_type& extents() const noexcept { return __extents_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type required_span_size() const noexcept {
+ index_type __size = 1;
+ for (size_t __r = 0; __r < extents_type::rank(); __r++)
+ __size *= __extents_.extent(__r);
+ return __size;
+ }
+
+ template <class... _Indices>
+ requires((sizeof...(_Indices) == extents_type::rank()) && (is_convertible_v<_Indices, index_type> && ...) &&
+ (is_nothrow_constructible_v<index_type, _Indices> && ...))
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type operator()(_Indices... __idx) const noexcept {
+ // Mappings are generally meant to be used for accessing allocations and are meant to guarantee to never
+ // return a value exceeding required_span_size(), which is used to know how large an allocation one needs
+ // Thus, this is a canonical point in multi-dimensional data structures to make invalid element access checks
+ // However, mdspan does check this on its own, so for now we avoid double checking in hardened mode
+ _LIBCPP_ASSERT_UNCATEGORIZED(__mdspan_detail::__is_multidimensional_index_in(__extents_, __idx...),
+ "layout_left::mapping: out of bounds indexing");
+ array<index_type, extents_type::rank()> __idx_a{static_cast<index_type>(__idx)...};
+ return [&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ index_type __res = 0;
+ ((__res = __idx_a[extents_type::rank() - 1 - _Pos] + __extents_.extent(extents_type::rank() - 1 - _Pos) * __res),
+ ...);
+ return __res;
+ }(make_index_sequence<sizeof...(_Indices)>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_unique() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_exhaustive() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_strided() noexcept { return true; }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_unique() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_exhaustive() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_strided() noexcept { return true; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type stride(rank_type __r) const noexcept
+ requires(extents_type::rank() > 0)
+ {
+ // While it would be caught by extents itself too, using a too large __r
+ // is functionally an out of bounds access on the stored information needed to compute strides
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __r < extents_type::rank(), "layout_left::mapping::stride(): invalid rank index");
+ index_type __s = 1;
+ for (rank_type __i = 0; __i < __r; __i++)
+ __s *= __extents_.extent(__i);
+ return __s;
+ }
+
+ template <class _OtherExtents>
+ requires(_OtherExtents::rank() == extents_type::rank())
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool
+ operator==(const mapping& __lhs, const mapping<_OtherExtents>& __rhs) noexcept {
+ return __lhs.extents() == __rhs.extents();
+ }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS extents_type __extents_{};
+};
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MDSPAN_LAYOUT_LEFT_H
diff --git a/libcxx/include/__cxx03/__mdspan/layout_right.h b/libcxx/include/__cxx03/__mdspan/layout_right.h
new file mode 100644
index 00000000000000..6842e9dc37fdcc
--- /dev/null
+++ b/libcxx/include/__cxx03/__mdspan/layout_right.h
@@ -0,0 +1,201 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MDSPAN_LAYOUT_RIGHT_H
+#define _LIBCPP___MDSPAN_LAYOUT_RIGHT_H
+
+#include <__assert>
+#include <__config>
+#include <__fwd/mdspan.h>
+#include <__mdspan/extents.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__utility/integer_sequence.h>
+#include <cinttypes>
+#include <cstddef>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Extents>
+class layout_right::mapping {
+public:
+ static_assert(__mdspan_detail::__is_extents<_Extents>::value,
+ "layout_right::mapping template argument must be a specialization of extents.");
+
+ using extents_type = _Extents;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using layout_type = layout_right;
+
+private:
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __required_span_size_is_representable(const extents_type& __ext) {
+ if constexpr (extents_type::rank() == 0)
+ return true;
+
+ index_type __prod = __ext.extent(0);
+ for (rank_type __r = 1; __r < extents_type::rank(); __r++) {
+ bool __overflowed = __builtin_mul_overflow(__prod, __ext.extent(__r), &__prod);
+ if (__overflowed)
+ return false;
+ }
+ return true;
+ }
+
+ static_assert(extents_type::rank_dynamic() > 0 || __required_span_size_is_representable(extents_type()),
+ "layout_right::mapping product of static extents must be representable as index_type.");
+
+public:
+ // [mdspan.layout.right.cons], constructors
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping() noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping(const mapping&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping(const extents_type& __ext) noexcept : __extents_(__ext) {
+ // not catching this could lead to out-of-bounds access later when used inside mdspan
+ // mapping<dextents<char, 2>> map(dextents<char, 2>(40,40)); map(3, 10) == -126
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __required_span_size_is_representable(__ext),
+ "layout_right::mapping extents ctor: product of extents must be representable as index_type.");
+ }
+
+ template <class _OtherExtents>
+ requires(is_constructible_v<extents_type, _OtherExtents>)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_OtherExtents, extents_type>)
+ mapping(const mapping<_OtherExtents>& __other) noexcept
+ : __extents_(__other.extents()) {
+ // not catching this could lead to out-of-bounds access later when used inside mdspan
+ // mapping<dextents<char, 2>> map(mapping<dextents<int, 2>>(dextents<int, 2>(40,40))); map(3, 10) == -126
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __mdspan_detail::__is_representable_as<index_type>(__other.required_span_size()),
+ "layout_right::mapping converting ctor: other.required_span_size() must be representable as index_type.");
+ }
+
+ template <class _OtherExtents>
+ requires(is_constructible_v<extents_type, _OtherExtents> && _OtherExtents::rank() <= 1)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!is_convertible_v<_OtherExtents, extents_type>)
+ mapping(const layout_left::mapping<_OtherExtents>& __other) noexcept
+ : __extents_(__other.extents()) {
+ // not catching this could lead to out-of-bounds access later when used inside mdspan
+ // Note: since this is constraint to rank 1, extents itself would catch the invalid conversion first
+ // and thus this assertion should never be triggered, but keeping it here for consistency
+ // layout_right::mapping<dextents<char, 1>> map(
+ // layout_left::mapping<dextents<unsigned, 1>>(dextents<unsigned, 1>(200))); map.extents().extent(0) ==
+ // -56
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __mdspan_detail::__is_representable_as<index_type>(__other.required_span_size()),
+ "layout_right::mapping converting ctor: other.required_span_size() must be representable as index_type.");
+ }
+
+ template <class _OtherExtents>
+ requires(is_constructible_v<extents_type, _OtherExtents>)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(extents_type::rank() > 0)
+ mapping(const layout_stride::mapping<_OtherExtents>& __other) noexcept
+ : __extents_(__other.extents()) {
+ if constexpr (extents_type::rank() > 0) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ ([&]() {
+ using _CommonType = common_type_t<typename extents_type::index_type, typename _OtherExtents::index_type>;
+ for (rank_type __r = 0; __r < extents_type::rank(); __r++)
+ if (static_cast<_CommonType>(stride(__r)) != static_cast<_CommonType>(__other.stride(__r)))
+ return false;
+ return true;
+ }()),
+ "layout_right::mapping from layout_stride ctor: strides are not compatible with layout_right.");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __mdspan_detail::__is_representable_as<index_type>(__other.required_span_size()),
+ "layout_right::mapping from layout_stride ctor: other.required_span_size() must be representable as "
+ "index_type.");
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping& operator=(const mapping&) noexcept = default;
+
+ // [mdspan.layout.right.obs], observers
+ _LIBCPP_HIDE_FROM_ABI constexpr const extents_type& extents() const noexcept { return __extents_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type required_span_size() const noexcept {
+ index_type __size = 1;
+ for (size_t __r = 0; __r < extents_type::rank(); __r++)
+ __size *= __extents_.extent(__r);
+ return __size;
+ }
+
+ template <class... _Indices>
+ requires((sizeof...(_Indices) == extents_type::rank()) && (is_convertible_v<_Indices, index_type> && ...) &&
+ (is_nothrow_constructible_v<index_type, _Indices> && ...))
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type operator()(_Indices... __idx) const noexcept {
+ // Mappings are generally meant to be used for accessing allocations and are meant to guarantee to never
+ // return a value exceeding required_span_size(), which is used to know how large an allocation one needs
+ // Thus, this is a canonical point in multi-dimensional data structures to make invalid element access checks
+ // However, mdspan does check this on its own, so for now we avoid double checking in hardened mode
+ _LIBCPP_ASSERT_UNCATEGORIZED(__mdspan_detail::__is_multidimensional_index_in(__extents_, __idx...),
+ "layout_right::mapping: out of bounds indexing");
+ return [&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ index_type __res = 0;
+ ((__res = static_cast<index_type>(__idx) + __extents_.extent(_Pos) * __res), ...);
+ return __res;
+ }(make_index_sequence<sizeof...(_Indices)>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_unique() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_exhaustive() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_strided() noexcept { return true; }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_unique() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_exhaustive() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_strided() noexcept { return true; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type stride(rank_type __r) const noexcept
+ requires(extents_type::rank() > 0)
+ {
+ // While it would be caught by extents itself too, using a too large __r
+ // is functionally an out of bounds access on the stored information needed to compute strides
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __r < extents_type::rank(), "layout_right::mapping::stride(): invalid rank index");
+ index_type __s = 1;
+ for (rank_type __i = extents_type::rank() - 1; __i > __r; __i--)
+ __s *= __extents_.extent(__i);
+ return __s;
+ }
+
+ template <class _OtherExtents>
+ requires(_OtherExtents::rank() == extents_type::rank())
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool
+ operator==(const mapping& __lhs, const mapping<_OtherExtents>& __rhs) noexcept {
+ return __lhs.extents() == __rhs.extents();
+ }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS extents_type __extents_{};
+};
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MDSPAN_LAYOUT_RIGHT_H
diff --git a/libcxx/include/__cxx03/__mdspan/layout_stride.h b/libcxx/include/__cxx03/__mdspan/layout_stride.h
new file mode 100644
index 00000000000000..86148ac849eca5
--- /dev/null
+++ b/libcxx/include/__cxx03/__mdspan/layout_stride.h
@@ -0,0 +1,366 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MDSPAN_LAYOUT_STRIDE_H
+#define _LIBCPP___MDSPAN_LAYOUT_STRIDE_H
+
+#include <__assert>
+#include <__config>
+#include <__fwd/mdspan.h>
+#include <__mdspan/extents.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__utility/as_const.h>
+#include <__utility/integer_sequence.h>
+#include <__utility/swap.h>
+#include <array>
+#include <cinttypes>
+#include <cstddef>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+namespace __mdspan_detail {
+template <class _Layout, class _Mapping>
+constexpr bool __is_mapping_of =
+ is_same_v<typename _Layout::template mapping<typename _Mapping::extents_type>, _Mapping>;
+
+template <class _Mapping>
+concept __layout_mapping_alike = requires {
+ requires __is_mapping_of<typename _Mapping::layout_type, _Mapping>;
+ requires __is_extents_v<typename _Mapping::extents_type>;
+ { _Mapping::is_always_strided() } -> same_as<bool>;
+ { _Mapping::is_always_exhaustive() } -> same_as<bool>;
+ { _Mapping::is_always_unique() } -> same_as<bool>;
+ bool_constant<_Mapping::is_always_strided()>::value;
+ bool_constant<_Mapping::is_always_exhaustive()>::value;
+ bool_constant<_Mapping::is_always_unique()>::value;
+};
+} // namespace __mdspan_detail
+
+template <class _Extents>
+class layout_stride::mapping {
+public:
+ static_assert(__mdspan_detail::__is_extents<_Extents>::value,
+ "layout_stride::mapping template argument must be a specialization of extents.");
+
+ using extents_type = _Extents;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using layout_type = layout_stride;
+
+private:
+ static constexpr rank_type __rank_ = extents_type::rank();
+
+ // Used for default construction check and mandates
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __required_span_size_is_representable(const extents_type& __ext) {
+ if constexpr (__rank_ == 0)
+ return true;
+
+ index_type __prod = __ext.extent(0);
+ for (rank_type __r = 1; __r < __rank_; __r++) {
+ bool __overflowed = __builtin_mul_overflow(__prod, __ext.extent(__r), &__prod);
+ if (__overflowed)
+ return false;
+ }
+ return true;
+ }
+
+ template <class _OtherIndexType>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool
+ __required_span_size_is_representable(const extents_type& __ext, span<_OtherIndexType, __rank_> __strides) {
+ if constexpr (__rank_ == 0)
+ return true;
+
+ index_type __size = 1;
+ for (rank_type __r = 0; __r < __rank_; __r++) {
+ // We can only check correct conversion of _OtherIndexType if it is an integral
+ if constexpr (is_integral_v<_OtherIndexType>) {
+ using _CommonType = common_type_t<index_type, _OtherIndexType>;
+ if (static_cast<_CommonType>(__strides[__r]) > static_cast<_CommonType>(numeric_limits<index_type>::max()))
+ return false;
+ }
+ if (__ext.extent(__r) == static_cast<index_type>(0))
+ return true;
+ index_type __prod = (__ext.extent(__r) - 1);
+ bool __overflowed_mul = __builtin_mul_overflow(__prod, static_cast<index_type>(__strides[__r]), &__prod);
+ if (__overflowed_mul)
+ return false;
+ bool __overflowed_add = __builtin_add_overflow(__size, __prod, &__size);
+ if (__overflowed_add)
+ return false;
+ }
+ return true;
+ }
+
+ // compute offset of a strided layout mapping
+ template <class _StridedMapping>
+ _LIBCPP_HIDE_FROM_ABI static constexpr index_type __offset(const _StridedMapping& __mapping) {
+ if constexpr (_StridedMapping::extents_type::rank() == 0) {
+ return static_cast<index_type>(__mapping());
+ } else if (__mapping.required_span_size() == static_cast<typename _StridedMapping::index_type>(0)) {
+ return static_cast<index_type>(0);
+ } else {
+ return [&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ return static_cast<index_type>(__mapping((_Pos ? 0 : 0)...));
+ }(make_index_sequence<__rank_>());
+ }
+ }
+
+ // compute the permutation for sorting the stride array
+ // we never actually sort the stride array
+ _LIBCPP_HIDE_FROM_ABI constexpr void __bubble_sort_by_strides(array<rank_type, __rank_>& __permute) const {
+ for (rank_type __i = __rank_ - 1; __i > 0; __i--) {
+ for (rank_type __r = 0; __r < __i; __r++) {
+ if (__strides_[__permute[__r]] > __strides_[__permute[__r + 1]]) {
+ swap(__permute[__r], __permute[__r + 1]);
+ } else {
+ // if two strides are the same then one of the associated extents must be 1 or 0
+ // both could be, but you can't have one larger than 1 come first
+ if ((__strides_[__permute[__r]] == __strides_[__permute[__r + 1]]) &&
+ (__extents_.extent(__permute[__r]) > static_cast<index_type>(1)))
+ swap(__permute[__r], __permute[__r + 1]);
+ }
+ }
+ }
+ }
+
+ static_assert(extents_type::rank_dynamic() > 0 || __required_span_size_is_representable(extents_type()),
+ "layout_stride::mapping product of static extents must be representable as index_type.");
+
+public:
+ // [mdspan.layout.stride.cons], constructors
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping() noexcept : __extents_(extents_type()) {
+ // Note the nominal precondition is covered by above static assert since
+ // if rank_dynamic is != 0 required_span_size is zero for default construction
+ if constexpr (__rank_ > 0) {
+ index_type __stride = 1;
+ for (rank_type __r = __rank_ - 1; __r > static_cast<rank_type>(0); __r--) {
+ __strides_[__r] = __stride;
+ __stride *= __extents_.extent(__r);
+ }
+ __strides_[0] = __stride;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping(const mapping&) noexcept = default;
+
+ template <class _OtherIndexType>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&>)
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping(const extents_type& __ext, span<_OtherIndexType, __rank_> __strides) noexcept
+ : __extents_(__ext), __strides_([&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ return __mdspan_detail::__possibly_empty_array<index_type, __rank_>{
+ static_cast<index_type>(std::as_const(__strides[_Pos]))...};
+ }(make_index_sequence<__rank_>())) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ ([&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ // For integrals we can do a pre-conversion check, for other types not
+ if constexpr (is_integral_v<_OtherIndexType>) {
+ return ((__strides[_Pos] > static_cast<_OtherIndexType>(0)) && ... && true);
+ } else {
+ return ((static_cast<index_type>(__strides[_Pos]) > static_cast<index_type>(0)) && ... && true);
+ }
+ }(make_index_sequence<__rank_>())),
+ "layout_stride::mapping ctor: all strides must be greater than 0");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __required_span_size_is_representable(__ext, __strides),
+ "layout_stride::mapping ctor: required span size is not representable as index_type.");
+ if constexpr (__rank_ > 1) {
+ _LIBCPP_ASSERT_UNCATEGORIZED(
+ ([&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ // basically sort the dimensions based on strides and extents, sorting is represented in permute array
+ array<rank_type, __rank_> __permute{_Pos...};
+ __bubble_sort_by_strides(__permute);
+
+ // check that this permutations represents a growing set
+ for (rank_type __i = 1; __i < __rank_; __i++)
+ if (static_cast<index_type>(__strides[__permute[__i]]) <
+ static_cast<index_type>(__strides[__permute[__i - 1]]) * __extents_.extent(__permute[__i - 1]))
+ return false;
+ return true;
+ }(make_index_sequence<__rank_>())),
+ "layout_stride::mapping ctor: the provided extents and strides lead to a non-unique mapping");
+ }
+ }
+
+ template <class _OtherIndexType>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&>)
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping(const extents_type& __ext,
+ const array<_OtherIndexType, __rank_>& __strides) noexcept
+ : mapping(__ext, span(__strides)) {}
+
+ template <class _StridedLayoutMapping>
+ requires(__mdspan_detail::__layout_mapping_alike<_StridedLayoutMapping> &&
+ is_constructible_v<extents_type, typename _StridedLayoutMapping::extents_type> &&
+ _StridedLayoutMapping::is_always_unique() && _StridedLayoutMapping::is_always_strided())
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(
+ !(is_convertible_v<typename _StridedLayoutMapping::extents_type, extents_type> &&
+ (__mdspan_detail::__is_mapping_of<layout_left, _StridedLayoutMapping> ||
+ __mdspan_detail::__is_mapping_of<layout_right, _StridedLayoutMapping> ||
+ __mdspan_detail::__is_mapping_of<layout_stride, _StridedLayoutMapping>)))
+ mapping(const _StridedLayoutMapping& __other) noexcept
+ : __extents_(__other.extents()), __strides_([&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ // stride() only compiles for rank > 0
+ if constexpr (__rank_ > 0) {
+ return __mdspan_detail::__possibly_empty_array<index_type, __rank_>{
+ static_cast<index_type>(__other.stride(_Pos))...};
+ } else {
+ return __mdspan_detail::__possibly_empty_array<index_type, 0>{};
+ }
+ }(make_index_sequence<__rank_>())) {
+ // stride() only compiles for rank > 0
+ if constexpr (__rank_ > 0) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ ([&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ return ((static_cast<index_type>(__other.stride(_Pos)) > static_cast<index_type>(0)) && ... && true);
+ }(make_index_sequence<__rank_>())),
+ "layout_stride::mapping converting ctor: all strides must be greater than 0");
+ }
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __mdspan_detail::__is_representable_as<index_type>(__other.required_span_size()),
+ "layout_stride::mapping converting ctor: other.required_span_size() must be representable as index_type.");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(static_cast<index_type>(0) == __offset(__other),
+ "layout_stride::mapping converting ctor: base offset of mapping must be zero.");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mapping& operator=(const mapping&) noexcept = default;
+
+ // [mdspan.layout.stride.obs], observers
+ _LIBCPP_HIDE_FROM_ABI constexpr const extents_type& extents() const noexcept { return __extents_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr array<index_type, __rank_> strides() const noexcept {
+ return [&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ return array<index_type, __rank_>{__strides_[_Pos]...};
+ }(make_index_sequence<__rank_>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type required_span_size() const noexcept {
+ if constexpr (__rank_ == 0) {
+ return static_cast<index_type>(1);
+ } else {
+ return [&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ if ((__extents_.extent(_Pos) * ... * 1) == 0)
+ return static_cast<index_type>(0);
+ else
+ return static_cast<index_type>(
+ static_cast<index_type>(1) +
+ (((__extents_.extent(_Pos) - static_cast<index_type>(1)) * __strides_[_Pos]) + ... +
+ static_cast<index_type>(0)));
+ }(make_index_sequence<__rank_>());
+ }
+ }
+
+ template <class... _Indices>
+ requires((sizeof...(_Indices) == __rank_) && (is_convertible_v<_Indices, index_type> && ...) &&
+ (is_nothrow_constructible_v<index_type, _Indices> && ...))
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type operator()(_Indices... __idx) const noexcept {
+ // Mappings are generally meant to be used for accessing allocations and are meant to guarantee to never
+ // return a value exceeding required_span_size(), which is used to know how large an allocation one needs
+ // Thus, this is a canonical point in multi-dimensional data structures to make invalid element access checks
+ // However, mdspan does check this on its own, so for now we avoid double checking in hardened mode
+ _LIBCPP_ASSERT_UNCATEGORIZED(__mdspan_detail::__is_multidimensional_index_in(__extents_, __idx...),
+ "layout_stride::mapping: out of bounds indexing");
+ return [&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ return ((static_cast<index_type>(__idx) * __strides_[_Pos]) + ... + index_type(0));
+ }(make_index_sequence<sizeof...(_Indices)>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_unique() noexcept { return true; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_exhaustive() noexcept { return false; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_strided() noexcept { return true; }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_unique() noexcept { return true; }
+ // The answer of this function is fairly complex in the case where one or more
+ // extents are zero.
+ // Technically it is meaningless to query is_exhaustive() in that case, but unfortunately
+ // the way the standard defines this function, we can't give a simple true or false then.
+ _LIBCPP_HIDE_FROM_ABI constexpr bool is_exhaustive() const noexcept {
+ if constexpr (__rank_ == 0)
+ return true;
+ else {
+ index_type __span_size = required_span_size();
+ if (__span_size == static_cast<index_type>(0)) {
+ if constexpr (__rank_ == 1)
+ return __strides_[0] == 1;
+ else {
+ rank_type __r_largest = 0;
+ for (rank_type __r = 1; __r < __rank_; __r++)
+ if (__strides_[__r] > __strides_[__r_largest])
+ __r_largest = __r;
+ for (rank_type __r = 0; __r < __rank_; __r++)
+ if (__extents_.extent(__r) == 0 && __r != __r_largest)
+ return false;
+ return true;
+ }
+ } else {
+ return required_span_size() == [&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ return (__extents_.extent(_Pos) * ... * static_cast<index_type>(1));
+ }(make_index_sequence<__rank_>());
+ }
+ }
+ }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_strided() noexcept { return true; }
+
+ // according to the standard layout_stride does not have a constraint on stride(r) for rank>0
+ // it still has the precondition though
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type stride(rank_type __r) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__r < __rank_, "layout_stride::mapping::stride(): invalid rank index");
+ return __strides_[__r];
+ }
+
+ template <class _OtherMapping>
+ requires(__mdspan_detail::__layout_mapping_alike<_OtherMapping> &&
+ (_OtherMapping::extents_type::rank() == __rank_) && _OtherMapping::is_always_strided())
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const mapping& __lhs, const _OtherMapping& __rhs) noexcept {
+ if (__offset(__rhs))
+ return false;
+ if constexpr (__rank_ == 0)
+ return true;
+ else {
+ return __lhs.extents() == __rhs.extents() && [&]<size_t... _Pos>(index_sequence<_Pos...>) {
+ // avoid warning when comparing signed and unsigner integers and pick the wider of two types
+ using _CommonType = common_type_t<index_type, typename _OtherMapping::index_type>;
+ return ((static_cast<_CommonType>(__lhs.stride(_Pos)) == static_cast<_CommonType>(__rhs.stride(_Pos))) && ... &&
+ true);
+ }(make_index_sequence<__rank_>());
+ }
+ }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS extents_type __extents_{};
+ _LIBCPP_NO_UNIQUE_ADDRESS __mdspan_detail::__possibly_empty_array<index_type, __rank_> __strides_{};
+};
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MDSPAN_LAYOUT_STRIDE_H
diff --git a/libcxx/include/__cxx03/__mdspan/mdspan.h b/libcxx/include/__cxx03/__mdspan/mdspan.h
new file mode 100644
index 00000000000000..1ff4fd4ba4a829
--- /dev/null
+++ b/libcxx/include/__cxx03/__mdspan/mdspan.h
@@ -0,0 +1,319 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MDSPAN_MDSPAN_H
+#define _LIBCPP___MDSPAN_MDSPAN_H
+
+#include <__assert>
+#include <__config>
+#include <__fwd/mdspan.h>
+#include <__mdspan/default_accessor.h>
+#include <__mdspan/extents.h>
+#include <__type_traits/extent.h>
+#include <__type_traits/is_abstract.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/rank.h>
+#include <__type_traits/remove_all_extents.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_pointer.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/integer_sequence.h>
+#include <array>
+#include <cinttypes>
+#include <cstddef>
+#include <limits>
+#include <span>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+// Helper for lightweight test checking that one did pass a layout policy as LayoutPolicy template argument
+namespace __mdspan_detail {
+template <class _Layout, class _Extents>
+concept __has_invalid_mapping = !requires { typename _Layout::template mapping<_Extents>; };
+} // namespace __mdspan_detail
+
+template <class _ElementType,
+ class _Extents,
+ class _LayoutPolicy = layout_right,
+ class _AccessorPolicy = default_accessor<_ElementType> >
+class mdspan {
+private:
+ static_assert(__mdspan_detail::__is_extents_v<_Extents>,
+ "mdspan: Extents template parameter must be a specialization of extents.");
+ static_assert(!is_array_v<_ElementType>, "mdspan: ElementType template parameter may not be an array type");
+ static_assert(!is_abstract_v<_ElementType>, "mdspan: ElementType template parameter may not be an abstract class");
+ static_assert(is_same_v<_ElementType, typename _AccessorPolicy::element_type>,
+ "mdspan: ElementType template parameter must match AccessorPolicy::element_type");
+ static_assert(!__mdspan_detail::__has_invalid_mapping<_LayoutPolicy, _Extents>,
+ "mdspan: LayoutPolicy template parameter is invalid. A common mistake is to pass a layout mapping "
+ "instead of a layout policy");
+
+public:
+ using extents_type = _Extents;
+ using layout_type = _LayoutPolicy;
+ using accessor_type = _AccessorPolicy;
+ using mapping_type = typename layout_type::template mapping<extents_type>;
+ using element_type = _ElementType;
+ using value_type = remove_cv_t<element_type>;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using data_handle_type = typename accessor_type::data_handle_type;
+ using reference = typename accessor_type::reference;
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr rank_type rank() noexcept { return extents_type::rank(); }
+ _LIBCPP_HIDE_FROM_ABI static constexpr rank_type rank_dynamic() noexcept { return extents_type::rank_dynamic(); }
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t static_extent(rank_type __r) noexcept {
+ return extents_type::static_extent(__r);
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type extent(rank_type __r) const noexcept {
+ return __map_.extents().extent(__r);
+ };
+
+public:
+ //--------------------------------------------------------------------------------
+ // [mdspan.mdspan.cons], mdspan constructors, assignment, and destructor
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan()
+ requires((extents_type::rank_dynamic() > 0) && is_default_constructible_v<data_handle_type> &&
+ is_default_constructible_v<mapping_type> && is_default_constructible_v<accessor_type>)
+ = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan(const mdspan&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan(mdspan&&) = default;
+
+ template <class... _OtherIndexTypes>
+ requires((is_convertible_v<_OtherIndexTypes, index_type> && ...) &&
+ (is_nothrow_constructible_v<index_type, _OtherIndexTypes> && ...) &&
+ ((sizeof...(_OtherIndexTypes) == rank()) || (sizeof...(_OtherIndexTypes) == rank_dynamic())) &&
+ is_constructible_v<mapping_type, extents_type> && is_default_constructible_v<accessor_type>)
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr mdspan(data_handle_type __p, _OtherIndexTypes... __exts)
+ : __ptr_(std::move(__p)), __map_(extents_type(static_cast<index_type>(std::move(__exts))...)), __acc_{} {}
+
+ template <class _OtherIndexType, size_t _Size>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&> &&
+ ((_Size == rank()) || (_Size == rank_dynamic())) && is_constructible_v<mapping_type, extents_type> &&
+ is_default_constructible_v<accessor_type>)
+ explicit(_Size != rank_dynamic())
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan(data_handle_type __p, const array<_OtherIndexType, _Size>& __exts)
+ : __ptr_(std::move(__p)), __map_(extents_type(__exts)), __acc_{} {}
+
+ template <class _OtherIndexType, size_t _Size>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&> &&
+ ((_Size == rank()) || (_Size == rank_dynamic())) && is_constructible_v<mapping_type, extents_type> &&
+ is_default_constructible_v<accessor_type>)
+ explicit(_Size != rank_dynamic())
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan(data_handle_type __p, span<_OtherIndexType, _Size> __exts)
+ : __ptr_(std::move(__p)), __map_(extents_type(__exts)), __acc_{} {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan(data_handle_type __p, const extents_type& __exts)
+ requires(is_default_constructible_v<accessor_type> && is_constructible_v<mapping_type, const extents_type&>)
+ : __ptr_(std::move(__p)), __map_(__exts), __acc_{} {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan(data_handle_type __p, const mapping_type& __m)
+ requires(is_default_constructible_v<accessor_type>)
+ : __ptr_(std::move(__p)), __map_(__m), __acc_{} {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan(data_handle_type __p, const mapping_type& __m, const accessor_type& __a)
+ : __ptr_(std::move(__p)), __map_(__m), __acc_(__a) {}
+
+ template <class _OtherElementType, class _OtherExtents, class _OtherLayoutPolicy, class _OtherAccessor>
+ requires(is_constructible_v<mapping_type, const typename _OtherLayoutPolicy::template mapping<_OtherExtents>&> &&
+ is_constructible_v<accessor_type, const _OtherAccessor&>)
+ explicit(!is_convertible_v<const typename _OtherLayoutPolicy::template mapping<_OtherExtents>&, mapping_type> ||
+ !is_convertible_v<const _OtherAccessor&, accessor_type>)
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan(
+ const mdspan<_OtherElementType, _OtherExtents, _OtherLayoutPolicy, _OtherAccessor>& __other)
+ : __ptr_(__other.__ptr_), __map_(__other.__map_), __acc_(__other.__acc_) {
+ static_assert(is_constructible_v<data_handle_type, const typename _OtherAccessor::data_handle_type&>,
+ "mdspan: incompatible data_handle_type for mdspan construction");
+ static_assert(
+ is_constructible_v<extents_type, _OtherExtents>, "mdspan: incompatible extents for mdspan construction");
+
+ // The following precondition is part of the standard, but is unlikely to be triggered.
+ // The extents constructor checks this and the mapping must be storing the extents, since
+ // its extents() function returns a const reference to extents_type.
+ // The only way this can be triggered is if the mapping conversion constructor would for example
+ // always construct its extents() only from the dynamic extents, instead of from the other extents.
+ if constexpr (rank() > 0) {
+ for (size_t __r = 0; __r < rank(); __r++) {
+ // Not catching this could lead to out of bounds errors later
+ // e.g. mdspan<int, dextents<char,1>, non_checking_layout> m =
+ // mdspan<int, dextents<unsigned, 1>, non_checking_layout>(ptr, 200); leads to an extent of -56 on m
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ (static_extent(__r) == dynamic_extent) ||
+ (static_cast<index_type>(__other.extent(__r)) == static_cast<index_type>(static_extent(__r))),
+ "mdspan: conversion mismatch of source dynamic extents with static extents");
+ }
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan& operator=(const mdspan&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr mdspan& operator=(mdspan&&) = default;
+
+ //--------------------------------------------------------------------------------
+ // [mdspan.mdspan.members], members
+
+ template <class... _OtherIndexTypes>
+ requires((is_convertible_v<_OtherIndexTypes, index_type> && ...) &&
+ (is_nothrow_constructible_v<index_type, _OtherIndexTypes> && ...) &&
+ (sizeof...(_OtherIndexTypes) == rank()))
+ _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](_OtherIndexTypes... __indices) const {
+ // Note the standard layouts would also check this, but user provided ones may not, so we
+ // check the precondition here
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__mdspan_detail::__is_multidimensional_index_in(extents(), __indices...),
+ "mdspan: operator[] out of bounds access");
+ return __acc_.access(__ptr_, __map_(static_cast<index_type>(std::move(__indices))...));
+ }
+
+ template <class _OtherIndexType>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&>)
+ _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](const array< _OtherIndexType, rank()>& __indices) const {
+ return __acc_.access(__ptr_, [&]<size_t... _Idxs>(index_sequence<_Idxs...>) {
+ return __map_(__indices[_Idxs]...);
+ }(make_index_sequence<rank()>()));
+ }
+
+ template <class _OtherIndexType>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&>)
+ _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](span<_OtherIndexType, rank()> __indices) const {
+ return __acc_.access(__ptr_, [&]<size_t... _Idxs>(index_sequence<_Idxs...>) {
+ return __map_(__indices[_Idxs]...);
+ }(make_index_sequence<rank()>()));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept {
+ // Could leave this as only checked in debug mode: semantically size() is never
+ // guaranteed to be related to any accessible range
+ _LIBCPP_ASSERT_UNCATEGORIZED(
+ false == ([&]<size_t... _Idxs>(index_sequence<_Idxs...>) {
+ size_type __prod = 1;
+ return (__builtin_mul_overflow(__prod, extent(_Idxs), &__prod) || ... || false);
+ }(make_index_sequence<rank()>())),
+ "mdspan: size() is not representable as size_type");
+ return [&]<size_t... _Idxs>(index_sequence<_Idxs...>) {
+ return ((static_cast<size_type>(__map_.extents().extent(_Idxs))) * ... * size_type(1));
+ }(make_index_sequence<rank()>());
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept {
+ return [&]<size_t... _Idxs>(index_sequence<_Idxs...>) {
+ return (rank() > 0) && ((__map_.extents().extent(_Idxs) == index_type(0)) || ... || false);
+ }(make_index_sequence<rank()>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void swap(mdspan& __x, mdspan& __y) noexcept {
+ swap(__x.__ptr_, __y.__ptr_);
+ swap(__x.__map_, __y.__map_);
+ swap(__x.__acc_, __y.__acc_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const extents_type& extents() const noexcept { return __map_.extents(); };
+ _LIBCPP_HIDE_FROM_ABI constexpr const data_handle_type& data_handle() const noexcept { return __ptr_; };
+ _LIBCPP_HIDE_FROM_ABI constexpr const mapping_type& mapping() const noexcept { return __map_; };
+ _LIBCPP_HIDE_FROM_ABI constexpr const accessor_type& accessor() const noexcept { return __acc_; };
+
+ // per LWG-4021 "mdspan::is_always_meow() should be noexcept"
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_unique() noexcept { return mapping_type::is_always_unique(); };
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_exhaustive() noexcept {
+ return mapping_type::is_always_exhaustive();
+ };
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool is_always_strided() noexcept {
+ return mapping_type::is_always_strided();
+ };
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool is_unique() const { return __map_.is_unique(); };
+ _LIBCPP_HIDE_FROM_ABI constexpr bool is_exhaustive() const { return __map_.is_exhaustive(); };
+ _LIBCPP_HIDE_FROM_ABI constexpr bool is_strided() const { return __map_.is_strided(); };
+ _LIBCPP_HIDE_FROM_ABI constexpr index_type stride(rank_type __r) const { return __map_.stride(__r); };
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS data_handle_type __ptr_{};
+ _LIBCPP_NO_UNIQUE_ADDRESS mapping_type __map_{};
+ _LIBCPP_NO_UNIQUE_ADDRESS accessor_type __acc_{};
+
+ template <class, class, class, class>
+ friend class mdspan;
+};
+
+# if _LIBCPP_STD_VER >= 26
+template <class _ElementType, class... _OtherIndexTypes>
+ requires((is_convertible_v<_OtherIndexTypes, size_t> && ...) && (sizeof...(_OtherIndexTypes) > 0))
+explicit mdspan(_ElementType*,
+ _OtherIndexTypes...) -> mdspan<_ElementType, extents<size_t, __maybe_static_ext<_OtherIndexTypes>...>>;
+# else
+template <class _ElementType, class... _OtherIndexTypes>
+ requires((is_convertible_v<_OtherIndexTypes, size_t> && ...) && (sizeof...(_OtherIndexTypes) > 0))
+explicit mdspan(_ElementType*,
+ _OtherIndexTypes...) -> mdspan<_ElementType, dextents<size_t, sizeof...(_OtherIndexTypes)>>;
+# endif
+
+template <class _Pointer>
+ requires(is_pointer_v<remove_reference_t<_Pointer>>)
+mdspan(_Pointer&&) -> mdspan<remove_pointer_t<remove_reference_t<_Pointer>>, extents<size_t>>;
+
+template <class _CArray>
+ requires(is_array_v<_CArray> && (rank_v<_CArray> == 1))
+mdspan(_CArray&) -> mdspan<remove_all_extents_t<_CArray>, extents<size_t, extent_v<_CArray, 0>>>;
+
+template <class _ElementType, class _OtherIndexType, size_t _Size>
+mdspan(_ElementType*, const array<_OtherIndexType, _Size>&) -> mdspan<_ElementType, dextents<size_t, _Size>>;
+
+template <class _ElementType, class _OtherIndexType, size_t _Size>
+mdspan(_ElementType*, span<_OtherIndexType, _Size>) -> mdspan<_ElementType, dextents<size_t, _Size>>;
+
+// This one is necessary because all the constructors take `data_handle_type`s, not
+// `_ElementType*`s, and `data_handle_type` is taken from `accessor_type::data_handle_type`, which
+// seems to throw off automatic deduction guides.
+template <class _ElementType, class _OtherIndexType, size_t... _ExtentsPack>
+mdspan(_ElementType*, const extents<_OtherIndexType, _ExtentsPack...>&)
+ -> mdspan<_ElementType, extents<_OtherIndexType, _ExtentsPack...>>;
+
+template <class _ElementType, class _MappingType>
+mdspan(_ElementType*, const _MappingType&)
+ -> mdspan<_ElementType, typename _MappingType::extents_type, typename _MappingType::layout_type>;
+
+template <class _MappingType, class _AccessorType>
+mdspan(const typename _AccessorType::data_handle_type, const _MappingType&, const _AccessorType&)
+ -> mdspan<typename _AccessorType::element_type,
+ typename _MappingType::extents_type,
+ typename _MappingType::layout_type,
+ _AccessorType>;
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MDSPAN_MDSPAN_H
diff --git a/libcxx/include/__cxx03/__memory/addressof.h b/libcxx/include/__cxx03/__memory/addressof.h
new file mode 100644
index 00000000000000..fa590212c49b96
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/addressof.h
@@ -0,0 +1,61 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ADDRESSOF_H
+#define _LIBCPP___MEMORY_ADDRESSOF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX17 _LIBCPP_NO_CFI _LIBCPP_HIDE_FROM_ABI _Tp* addressof(_Tp& __x) _NOEXCEPT {
+ return __builtin_addressof(__x);
+}
+
+#if defined(_LIBCPP_HAS_OBJC_ARC) && !defined(_LIBCPP_PREDEFINED_OBJC_ARC_ADDRESSOF)
+// Objective-C++ Automatic Reference Counting uses qualified pointers
+// that require special addressof() signatures. When
+// _LIBCPP_PREDEFINED_OBJC_ARC_ADDRESSOF is defined, the compiler
+// itself is providing these definitions. Otherwise, we provide them.
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI __strong _Tp* addressof(__strong _Tp& __x) _NOEXCEPT {
+ return &__x;
+}
+
+# ifdef _LIBCPP_HAS_OBJC_ARC_WEAK
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI __weak _Tp* addressof(__weak _Tp& __x) _NOEXCEPT {
+ return &__x;
+}
+# endif
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI __autoreleasing _Tp* addressof(__autoreleasing _Tp& __x) _NOEXCEPT {
+ return &__x;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI __unsafe_unretained _Tp* addressof(__unsafe_unretained _Tp& __x) _NOEXCEPT {
+ return &__x;
+}
+#endif
+
+#if !defined(_LIBCPP_CXX03_LANG)
+template <class _Tp>
+_Tp* addressof(const _Tp&&) noexcept = delete;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_ADDRESSOF_H
diff --git a/libcxx/include/__cxx03/__memory/align.h b/libcxx/include/__cxx03/__memory/align.h
new file mode 100644
index 00000000000000..bbb995f4a8c8ed
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/align.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ALIGN_H
+#define _LIBCPP___MEMORY_ALIGN_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_EXPORTED_FROM_ABI void* align(size_t __align, size_t __sz, void*& __ptr, size_t& __space);
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_ALIGN_H
diff --git a/libcxx/include/__cxx03/__memory/aligned_alloc.h b/libcxx/include/__cxx03/__memory/aligned_alloc.h
new file mode 100644
index 00000000000000..cb424328bcafc1
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/aligned_alloc.h
@@ -0,0 +1,64 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ALIGNED_ALLOC_H
+#define _LIBCPP___MEMORY_ALIGNED_ALLOC_H
+
+#include <__config>
+#include <cstddef>
+#include <cstdlib>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
+
+// Low-level helpers to call the aligned allocation and deallocation functions
+// on the target platform. This is used to implement libc++'s own memory
+// allocation routines -- if you need to allocate memory inside the library,
+// chances are that you want to use `__libcpp_allocate` instead.
+//
+// Returns the allocated memory, or `nullptr` on failure.
+inline _LIBCPP_HIDE_FROM_ABI void* __libcpp_aligned_alloc(std::size_t __alignment, std::size_t __size) {
+# if defined(_LIBCPP_MSVCRT_LIKE)
+ return ::_aligned_malloc(__size, __alignment);
+# elif _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_C11_ALIGNED_ALLOC)
+ // aligned_alloc() requires that __size is a multiple of __alignment,
+ // but for C++ [new.delete.general], only states "if the value of an
+ // alignment argument passed to any of these functions is not a valid
+ // alignment value, the behavior is undefined".
+ // To handle calls such as ::operator new(1, std::align_val_t(128)), we
+ // round __size up to the next multiple of __alignment.
+ size_t __rounded_size = (__size + __alignment - 1) & ~(__alignment - 1);
+ // Rounding up could have wrapped around to zero, so we have to add another
+ // max() ternary to the actual call site to avoid succeeded in that case.
+ return ::aligned_alloc(__alignment, __size > __rounded_size ? __size : __rounded_size);
+# else
+ void* __result = nullptr;
+ (void)::posix_memalign(&__result, __alignment, __size);
+ // If posix_memalign fails, __result is unmodified so we still return `nullptr`.
+ return __result;
+# endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void __libcpp_aligned_free(void* __ptr) {
+# if defined(_LIBCPP_MSVCRT_LIKE)
+ ::_aligned_free(__ptr);
+# else
+ ::free(__ptr);
+# endif
+}
+
+#endif // !_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_ALIGNED_ALLOC_H
diff --git a/libcxx/include/__cxx03/__memory/allocate_at_least.h b/libcxx/include/__cxx03/__memory/allocate_at_least.h
new file mode 100644
index 00000000000000..df73d9a2e94aa6
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/allocate_at_least.h
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ALLOCATE_AT_LEAST_H
+#define _LIBCPP___MEMORY_ALLOCATE_AT_LEAST_H
+
+#include <__config>
+#include <__memory/allocator_traits.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Alloc>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto __allocate_at_least(_Alloc& __alloc, size_t __n) {
+ return std::allocator_traits<_Alloc>::allocate_at_least(__alloc, __n);
+}
+
+#else
+
+template <class _Pointer>
+struct __allocation_result {
+ _Pointer ptr;
+ size_t count;
+};
+
+template <class _Alloc>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR __allocation_result<typename allocator_traits<_Alloc>::pointer>
+__allocate_at_least(_Alloc& __alloc, size_t __n) {
+ return {__alloc.allocate(__n), __n};
+}
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_ALLOCATE_AT_LEAST_H
diff --git a/libcxx/include/__cxx03/__memory/allocation_guard.h b/libcxx/include/__cxx03/__memory/allocation_guard.h
new file mode 100644
index 00000000000000..cb870af7be6760
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/allocation_guard.h
@@ -0,0 +1,108 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ALLOCATION_GUARD_H
+#define _LIBCPP___MEMORY_ALLOCATION_GUARD_H
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory/allocator_traits.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Helper class to allocate memory using an Allocator in an exception safe
+// manner.
+//
+// The intended usage of this class is as follows:
+//
+// 0
+// 1 __allocation_guard<SomeAllocator> guard(alloc, 10);
+// 2 do_some_initialization_that_may_throw(guard.__get());
+// 3 save_allocated_pointer_in_a_noexcept_operation(guard.__release_ptr());
+// 4
+//
+// If line (2) throws an exception during initialization of the memory, the
+// guard's destructor will be called, and the memory will be released using
+// Allocator deallocation. Otherwise, we release the memory from the guard on
+// line (3) in an operation that can't throw -- after that, the guard is not
+// responsible for the memory anymore.
+//
+// This is similar to a unique_ptr, except it's easier to use with a
+// custom allocator.
+template <class _Alloc>
+struct __allocation_guard {
+ using _Pointer = typename allocator_traits<_Alloc>::pointer;
+ using _Size = typename allocator_traits<_Alloc>::size_type;
+
+ template <class _AllocT> // we perform the allocator conversion inside the constructor
+ _LIBCPP_HIDE_FROM_ABI explicit __allocation_guard(_AllocT __alloc, _Size __n)
+ : __alloc_(std::move(__alloc)),
+ __n_(__n),
+ __ptr_(allocator_traits<_Alloc>::allocate(__alloc_, __n_)) // initialization order is important
+ {}
+
+ _LIBCPP_HIDE_FROM_ABI ~__allocation_guard() _NOEXCEPT { __destroy(); }
+
+ _LIBCPP_HIDE_FROM_ABI __allocation_guard(const __allocation_guard&) = delete;
+ _LIBCPP_HIDE_FROM_ABI __allocation_guard(__allocation_guard&& __other) _NOEXCEPT
+ : __alloc_(std::move(__other.__alloc_)),
+ __n_(__other.__n_),
+ __ptr_(__other.__ptr_) {
+ __other.__ptr_ = nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __allocation_guard& operator=(const __allocation_guard& __other) = delete;
+ _LIBCPP_HIDE_FROM_ABI __allocation_guard& operator=(__allocation_guard&& __other) _NOEXCEPT {
+ if (std::addressof(__other) != this) {
+ __destroy();
+
+ __alloc_ = std::move(__other.__alloc_);
+ __n_ = __other.__n_;
+ __ptr_ = __other.__ptr_;
+ __other.__ptr_ = nullptr;
+ }
+
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Pointer
+ __release_ptr() _NOEXCEPT { // not called __release() because it's a keyword in objective-c++
+ _Pointer __tmp = __ptr_;
+ __ptr_ = nullptr;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Pointer __get() const _NOEXCEPT { return __ptr_; }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI void __destroy() _NOEXCEPT {
+ if (__ptr_ != nullptr) {
+ allocator_traits<_Alloc>::deallocate(__alloc_, __ptr_, __n_);
+ }
+ }
+
+ _Alloc __alloc_;
+ _Size __n_;
+ _Pointer __ptr_;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_ALLOCATION_GUARD_H
diff --git a/libcxx/include/__cxx03/__memory/allocator.h b/libcxx/include/__cxx03/__memory/allocator.h
new file mode 100644
index 00000000000000..2d8624e771bce0
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/allocator.h
@@ -0,0 +1,268 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ALLOCATOR_H
+#define _LIBCPP___MEMORY_ALLOCATOR_H
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory/allocate_at_least.h>
+#include <__memory/allocator_traits.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/is_volatile.h>
+#include <__utility/forward.h>
+#include <cstddef>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+class allocator;
+
+#if _LIBCPP_STD_VER <= 17
+// These specializations shouldn't be marked _LIBCPP_DEPRECATED_IN_CXX17.
+// Specializing allocator<void> is deprecated, but not using it.
+template <>
+class _LIBCPP_TEMPLATE_VIS allocator<void> {
+public:
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef void* pointer;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const void* const_pointer;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef void value_type;
+
+ template <class _Up>
+ struct _LIBCPP_DEPRECATED_IN_CXX17 rebind {
+ typedef allocator<_Up> other;
+ };
+};
+
+// TODO(LLVM 20): Remove the escape hatch
+# ifdef _LIBCPP_ENABLE_REMOVED_ALLOCATOR_CONST
+template <>
+class _LIBCPP_TEMPLATE_VIS allocator<const void> {
+public:
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const void* pointer;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const void* const_pointer;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const void value_type;
+
+ template <class _Up>
+ struct _LIBCPP_DEPRECATED_IN_CXX17 rebind {
+ typedef allocator<_Up> other;
+ };
+};
+# endif // _LIBCPP_ENABLE_REMOVED_ALLOCATOR_CONST
+#endif // _LIBCPP_STD_VER <= 17
+
+// This class provides a non-trivial default constructor to the class that derives from it
+// if the condition is satisfied.
+//
+// The second template parameter exists to allow giving a unique type to __non_trivial_if,
+// which makes it possible to avoid breaking the ABI when making this a base class of an
+// existing class. Without that, imagine we have classes D1 and D2, both of which used to
+// have no base classes, but which now derive from __non_trivial_if. The layout of a class
+// that inherits from both D1 and D2 will change because the two __non_trivial_if base
+// classes are not allowed to share the same address.
+//
+// By making those __non_trivial_if base classes unique, we work around this problem and
+// it is safe to start deriving from __non_trivial_if in existing classes.
+template <bool _Cond, class _Unique>
+struct __non_trivial_if {};
+
+template <class _Unique>
+struct __non_trivial_if<true, _Unique> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __non_trivial_if() _NOEXCEPT {}
+};
+
+// allocator
+//
+// Note: For ABI compatibility between C++20 and previous standards, we make
+// allocator<void> trivial in C++20.
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS allocator : private __non_trivial_if<!is_void<_Tp>::value, allocator<_Tp> > {
+ static_assert(!is_const<_Tp>::value, "std::allocator does not support const types");
+ static_assert(!is_volatile<_Tp>::value, "std::allocator does not support volatile types");
+
+public:
+ typedef size_t size_type;
+ typedef ptrdiff_t difference_type;
+ typedef _Tp value_type;
+ typedef true_type propagate_on_container_move_assignment;
+#if _LIBCPP_STD_VER <= 23 || defined(_LIBCPP_ENABLE_CXX26_REMOVED_ALLOCATOR_MEMBERS)
+ _LIBCPP_DEPRECATED_IN_CXX23 typedef true_type is_always_equal;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 allocator() _NOEXCEPT = default;
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 allocator(const allocator<_Up>&) _NOEXCEPT {}
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp* allocate(size_t __n) {
+ if (__n > allocator_traits<allocator>::max_size(*this))
+ __throw_bad_array_new_length();
+ if (__libcpp_is_constant_evaluated()) {
+ return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp)));
+ } else {
+ return static_cast<_Tp*>(std::__libcpp_allocate(__n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)));
+ }
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr allocation_result<_Tp*> allocate_at_least(size_t __n) {
+ return {allocate(__n), __n};
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void deallocate(_Tp* __p, size_t __n) _NOEXCEPT {
+ if (__libcpp_is_constant_evaluated()) {
+ ::operator delete(__p);
+ } else {
+ std::__libcpp_deallocate((void*)__p, __n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));
+ }
+ }
+
+ // C++20 Removed members
+#if _LIBCPP_STD_VER <= 17
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef _Tp* pointer;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* const_pointer;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef _Tp& reference;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& const_reference;
+
+ template <class _Up>
+ struct _LIBCPP_DEPRECATED_IN_CXX17 rebind {
+ typedef allocator<_Up> other;
+ };
+
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI pointer address(reference __x) const _NOEXCEPT {
+ return std::addressof(__x);
+ }
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI const_pointer address(const_reference __x) const _NOEXCEPT {
+ return std::addressof(__x);
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_DEPRECATED_IN_CXX17 _Tp* allocate(size_t __n, const void*) {
+ return allocate(__n);
+ }
+
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT {
+ return size_type(~0) / sizeof(_Tp);
+ }
+
+ template <class _Up, class... _Args>
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI void construct(_Up* __p, _Args&&... __args) {
+ ::new ((void*)__p) _Up(std::forward<_Args>(__args)...);
+ }
+
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI void destroy(pointer __p) { __p->~_Tp(); }
+#endif
+};
+
+// TODO(LLVM 20): Remove the escape hatch
+#ifdef _LIBCPP_ENABLE_REMOVED_ALLOCATOR_CONST
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS allocator<const _Tp>
+ : private __non_trivial_if<!is_void<_Tp>::value, allocator<const _Tp> > {
+ static_assert(!is_volatile<_Tp>::value, "std::allocator does not support volatile types");
+
+public:
+ typedef size_t size_type;
+ typedef ptrdiff_t difference_type;
+ typedef const _Tp value_type;
+ typedef true_type propagate_on_container_move_assignment;
+# if _LIBCPP_STD_VER <= 23 || defined(_LIBCPP_ENABLE_CXX26_REMOVED_ALLOCATOR_MEMBERS)
+ _LIBCPP_DEPRECATED_IN_CXX23 typedef true_type is_always_equal;
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 allocator() _NOEXCEPT = default;
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 allocator(const allocator<_Up>&) _NOEXCEPT {}
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const _Tp* allocate(size_t __n) {
+ if (__n > allocator_traits<allocator>::max_size(*this))
+ __throw_bad_array_new_length();
+ if (__libcpp_is_constant_evaluated()) {
+ return static_cast<const _Tp*>(::operator new(__n * sizeof(_Tp)));
+ } else {
+ return static_cast<const _Tp*>(std::__libcpp_allocate(__n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)));
+ }
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr allocation_result<const _Tp*> allocate_at_least(size_t __n) {
+ return {allocate(__n), __n};
+ }
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void deallocate(const _Tp* __p, size_t __n) {
+ if (__libcpp_is_constant_evaluated()) {
+ ::operator delete(const_cast<_Tp*>(__p));
+ } else {
+ std::__libcpp_deallocate((void*)const_cast<_Tp*>(__p), __n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));
+ }
+ }
+
+ // C++20 Removed members
+# if _LIBCPP_STD_VER <= 17
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* pointer;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* const_pointer;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& reference;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& const_reference;
+
+ template <class _Up>
+ struct _LIBCPP_DEPRECATED_IN_CXX17 rebind {
+ typedef allocator<_Up> other;
+ };
+
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI const_pointer address(const_reference __x) const _NOEXCEPT {
+ return std::addressof(__x);
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_DEPRECATED_IN_CXX17 const _Tp* allocate(size_t __n, const void*) {
+ return allocate(__n);
+ }
+
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT {
+ return size_type(~0) / sizeof(_Tp);
+ }
+
+ template <class _Up, class... _Args>
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI void construct(_Up* __p, _Args&&... __args) {
+ ::new ((void*)__p) _Up(std::forward<_Args>(__args)...);
+ }
+
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI void destroy(pointer __p) { __p->~_Tp(); }
+# endif
+};
+#endif // _LIBCPP_ENABLE_REMOVED_ALLOCATOR_CONST
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+operator==(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {
+ return true;
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {
+ return false;
+}
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_ALLOCATOR_H
diff --git a/libcxx/include/__cxx03/__memory/allocator_arg_t.h b/libcxx/include/__cxx03/__memory/allocator_arg_t.h
new file mode 100644
index 00000000000000..7e66da740cd4fd
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/allocator_arg_t.h
@@ -0,0 +1,75 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FUNCTIONAL_ALLOCATOR_ARG_T_H
+#define _LIBCPP___FUNCTIONAL_ALLOCATOR_ARG_T_H
+
+#include <__config>
+#include <__memory/uses_allocator.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct _LIBCPP_TEMPLATE_VIS allocator_arg_t {
+ explicit allocator_arg_t() = default;
+};
+
+#if _LIBCPP_STD_VER >= 17
+inline constexpr allocator_arg_t allocator_arg = allocator_arg_t();
+#elif !defined(_LIBCPP_CXX03_LANG)
+constexpr allocator_arg_t allocator_arg = allocator_arg_t();
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+// allocator construction
+
+template <class _Tp, class _Alloc, class... _Args>
+struct __uses_alloc_ctor_imp {
+ typedef _LIBCPP_NODEBUG __remove_cvref_t<_Alloc> _RawAlloc;
+ static const bool __ua = uses_allocator<_Tp, _RawAlloc>::value;
+ static const bool __ic = is_constructible<_Tp, allocator_arg_t, _Alloc, _Args...>::value;
+ static const int value = __ua ? 2 - __ic : 0;
+};
+
+template <class _Tp, class _Alloc, class... _Args>
+struct __uses_alloc_ctor : integral_constant<int, __uses_alloc_ctor_imp<_Tp, _Alloc, _Args...>::value> {};
+
+template <class _Tp, class _Allocator, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI void
+__user_alloc_construct_impl(integral_constant<int, 0>, _Tp* __storage, const _Allocator&, _Args&&... __args) {
+ new (__storage) _Tp(std::forward<_Args>(__args)...);
+}
+
+// FIXME: This should have a version which takes a non-const alloc.
+template <class _Tp, class _Allocator, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI void
+__user_alloc_construct_impl(integral_constant<int, 1>, _Tp* __storage, const _Allocator& __a, _Args&&... __args) {
+ new (__storage) _Tp(allocator_arg, __a, std::forward<_Args>(__args)...);
+}
+
+// FIXME: This should have a version which takes a non-const alloc.
+template <class _Tp, class _Allocator, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI void
+__user_alloc_construct_impl(integral_constant<int, 2>, _Tp* __storage, const _Allocator& __a, _Args&&... __args) {
+ new (__storage) _Tp(std::forward<_Args>(__args)..., __a);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_ALLOCATOR_ARG_T_H
diff --git a/libcxx/include/__cxx03/__memory/allocator_destructor.h b/libcxx/include/__cxx03/__memory/allocator_destructor.h
new file mode 100644
index 00000000000000..ed3d8918f5fe3f
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/allocator_destructor.h
@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ALLOCATOR_DESTRUCTOR_H
+#define _LIBCPP___MEMORY_ALLOCATOR_DESTRUCTOR_H
+
+#include <__config>
+#include <__memory/allocator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Alloc>
+class __allocator_destructor {
+ typedef _LIBCPP_NODEBUG allocator_traits<_Alloc> __alloc_traits;
+
+public:
+ typedef _LIBCPP_NODEBUG typename __alloc_traits::pointer pointer;
+ typedef _LIBCPP_NODEBUG typename __alloc_traits::size_type size_type;
+
+private:
+ _Alloc& __alloc_;
+ size_type __s_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __allocator_destructor(_Alloc& __a, size_type __s) _NOEXCEPT : __alloc_(__a), __s_(__s) {}
+ _LIBCPP_HIDE_FROM_ABI void operator()(pointer __p) _NOEXCEPT { __alloc_traits::deallocate(__alloc_, __p, __s_); }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_ALLOCATOR_DESTRUCTOR_H
diff --git a/libcxx/include/__cxx03/__memory/allocator_traits.h b/libcxx/include/__cxx03/__memory/allocator_traits.h
new file mode 100644
index 00000000000000..c5fcc89327b8f7
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/allocator_traits.h
@@ -0,0 +1,424 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ALLOCATOR_TRAITS_H
+#define _LIBCPP___MEMORY_ALLOCATOR_TRAITS_H
+
+#include <__config>
+#include <__memory/construct_at.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_empty.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/remove_reference.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <cstddef>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#define _LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(NAME, PROPERTY) \
+ template <class _Tp, class = void> \
+ struct NAME : false_type {}; \
+ template <class _Tp> \
+ struct NAME<_Tp, __void_t<typename _Tp::PROPERTY > > : true_type {}
+
+// __pointer
+template <class _Tp,
+ class _Alloc,
+ class _RawAlloc = __libcpp_remove_reference_t<_Alloc>,
+ bool = __has_pointer<_RawAlloc>::value>
+struct __pointer {
+ using type _LIBCPP_NODEBUG = typename _RawAlloc::pointer;
+};
+template <class _Tp, class _Alloc, class _RawAlloc>
+struct __pointer<_Tp, _Alloc, _RawAlloc, false> {
+ using type _LIBCPP_NODEBUG = _Tp*;
+};
+
+// __const_pointer
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_const_pointer, const_pointer);
+template <class _Tp, class _Ptr, class _Alloc, bool = __has_const_pointer<_Alloc>::value>
+struct __const_pointer {
+ using type _LIBCPP_NODEBUG = typename _Alloc::const_pointer;
+};
+template <class _Tp, class _Ptr, class _Alloc>
+struct __const_pointer<_Tp, _Ptr, _Alloc, false> {
+#ifdef _LIBCPP_CXX03_LANG
+ using type = typename pointer_traits<_Ptr>::template rebind<const _Tp>::other;
+#else
+ using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<const _Tp>;
+#endif
+};
+
+// __void_pointer
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_void_pointer, void_pointer);
+template <class _Ptr, class _Alloc, bool = __has_void_pointer<_Alloc>::value>
+struct __void_pointer {
+ using type _LIBCPP_NODEBUG = typename _Alloc::void_pointer;
+};
+template <class _Ptr, class _Alloc>
+struct __void_pointer<_Ptr, _Alloc, false> {
+#ifdef _LIBCPP_CXX03_LANG
+ using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<void>::other;
+#else
+ using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<void>;
+#endif
+};
+
+// __const_void_pointer
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_const_void_pointer, const_void_pointer);
+template <class _Ptr, class _Alloc, bool = __has_const_void_pointer<_Alloc>::value>
+struct __const_void_pointer {
+ using type _LIBCPP_NODEBUG = typename _Alloc::const_void_pointer;
+};
+template <class _Ptr, class _Alloc>
+struct __const_void_pointer<_Ptr, _Alloc, false> {
+#ifdef _LIBCPP_CXX03_LANG
+ using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<const void>::other;
+#else
+ using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<const void>;
+#endif
+};
+
+// __size_type
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_size_type, size_type);
+template <class _Alloc, class _DiffType, bool = __has_size_type<_Alloc>::value>
+struct __size_type : make_unsigned<_DiffType> {};
+template <class _Alloc, class _DiffType>
+struct __size_type<_Alloc, _DiffType, true> {
+ using type _LIBCPP_NODEBUG = typename _Alloc::size_type;
+};
+
+// __alloc_traits_difference_type
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_alloc_traits_difference_type, difference_type);
+template <class _Alloc, class _Ptr, bool = __has_alloc_traits_difference_type<_Alloc>::value>
+struct __alloc_traits_difference_type {
+ using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::difference_type;
+};
+template <class _Alloc, class _Ptr>
+struct __alloc_traits_difference_type<_Alloc, _Ptr, true> {
+ using type _LIBCPP_NODEBUG = typename _Alloc::difference_type;
+};
+
+// __propagate_on_container_copy_assignment
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_propagate_on_container_copy_assignment, propagate_on_container_copy_assignment);
+template <class _Alloc, bool = __has_propagate_on_container_copy_assignment<_Alloc>::value>
+struct __propagate_on_container_copy_assignment : false_type {};
+template <class _Alloc>
+struct __propagate_on_container_copy_assignment<_Alloc, true> {
+ using type _LIBCPP_NODEBUG = typename _Alloc::propagate_on_container_copy_assignment;
+};
+
+// __propagate_on_container_move_assignment
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_propagate_on_container_move_assignment, propagate_on_container_move_assignment);
+template <class _Alloc, bool = __has_propagate_on_container_move_assignment<_Alloc>::value>
+struct __propagate_on_container_move_assignment : false_type {};
+template <class _Alloc>
+struct __propagate_on_container_move_assignment<_Alloc, true> {
+ using type _LIBCPP_NODEBUG = typename _Alloc::propagate_on_container_move_assignment;
+};
+
+// __propagate_on_container_swap
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_propagate_on_container_swap, propagate_on_container_swap);
+template <class _Alloc, bool = __has_propagate_on_container_swap<_Alloc>::value>
+struct __propagate_on_container_swap : false_type {};
+template <class _Alloc>
+struct __propagate_on_container_swap<_Alloc, true> {
+ using type _LIBCPP_NODEBUG = typename _Alloc::propagate_on_container_swap;
+};
+
+// __is_always_equal
+_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_is_always_equal, is_always_equal);
+template <class _Alloc, bool = __has_is_always_equal<_Alloc>::value>
+struct __is_always_equal : is_empty<_Alloc> {};
+template <class _Alloc>
+struct __is_always_equal<_Alloc, true> {
+ using type _LIBCPP_NODEBUG = typename _Alloc::is_always_equal;
+};
+
+// __allocator_traits_rebind
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Tp, class _Up, class = void>
+struct __has_rebind_other : false_type {};
+template <class _Tp, class _Up>
+struct __has_rebind_other<_Tp, _Up, __void_t<typename _Tp::template rebind<_Up>::other> > : true_type {};
+
+template <class _Tp, class _Up, bool = __has_rebind_other<_Tp, _Up>::value>
+struct __allocator_traits_rebind {
+ static_assert(__has_rebind_other<_Tp, _Up>::value, "This allocator has to implement rebind");
+ using type _LIBCPP_NODEBUG = typename _Tp::template rebind<_Up>::other;
+};
+template <template <class, class...> class _Alloc, class _Tp, class... _Args, class _Up>
+struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, true> {
+ using type _LIBCPP_NODEBUG = typename _Alloc<_Tp, _Args...>::template rebind<_Up>::other;
+};
+template <template <class, class...> class _Alloc, class _Tp, class... _Args, class _Up>
+struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, false> {
+ using type _LIBCPP_NODEBUG = _Alloc<_Up, _Args...>;
+};
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+template <class _Alloc, class _Tp>
+using __allocator_traits_rebind_t = typename __allocator_traits_rebind<_Alloc, _Tp>::type;
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+
+// __has_allocate_hint
+template <class _Alloc, class _SizeType, class _ConstVoidPtr, class = void>
+struct __has_allocate_hint : false_type {};
+
+template <class _Alloc, class _SizeType, class _ConstVoidPtr>
+struct __has_allocate_hint<
+ _Alloc,
+ _SizeType,
+ _ConstVoidPtr,
+ decltype((void)std::declval<_Alloc>().allocate(std::declval<_SizeType>(), std::declval<_ConstVoidPtr>()))>
+ : true_type {};
+
+// __has_construct
+template <class, class _Alloc, class... _Args>
+struct __has_construct_impl : false_type {};
+
+template <class _Alloc, class... _Args>
+struct __has_construct_impl<decltype((void)std::declval<_Alloc>().construct(std::declval<_Args>()...)),
+ _Alloc,
+ _Args...> : true_type {};
+
+template <class _Alloc, class... _Args>
+struct __has_construct : __has_construct_impl<void, _Alloc, _Args...> {};
+
+// __has_destroy
+template <class _Alloc, class _Pointer, class = void>
+struct __has_destroy : false_type {};
+
+template <class _Alloc, class _Pointer>
+struct __has_destroy<_Alloc, _Pointer, decltype((void)std::declval<_Alloc>().destroy(std::declval<_Pointer>()))>
+ : true_type {};
+
+// __has_max_size
+template <class _Alloc, class = void>
+struct __has_max_size : false_type {};
+
+template <class _Alloc>
+struct __has_max_size<_Alloc, decltype((void)std::declval<_Alloc&>().max_size())> : true_type {};
+
+// __has_select_on_container_copy_construction
+template <class _Alloc, class = void>
+struct __has_select_on_container_copy_construction : false_type {};
+
+template <class _Alloc>
+struct __has_select_on_container_copy_construction<
+ _Alloc,
+ decltype((void)std::declval<_Alloc>().select_on_container_copy_construction())> : true_type {};
+
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Pointer, class _SizeType = size_t>
+struct allocation_result {
+ _Pointer ptr;
+ _SizeType count;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(allocation_result);
+
+#endif // _LIBCPP_STD_VER
+
+template <class _Alloc>
+struct _LIBCPP_TEMPLATE_VIS allocator_traits {
+ using allocator_type = _Alloc;
+ using value_type = typename allocator_type::value_type;
+ using pointer = typename __pointer<value_type, allocator_type>::type;
+ using const_pointer = typename __const_pointer<value_type, pointer, allocator_type>::type;
+ using void_pointer = typename __void_pointer<pointer, allocator_type>::type;
+ using const_void_pointer = typename __const_void_pointer<pointer, allocator_type>::type;
+ using difference_type = typename __alloc_traits_difference_type<allocator_type, pointer>::type;
+ using size_type = typename __size_type<allocator_type, difference_type>::type;
+ using propagate_on_container_copy_assignment =
+ typename __propagate_on_container_copy_assignment<allocator_type>::type;
+ using propagate_on_container_move_assignment =
+ typename __propagate_on_container_move_assignment<allocator_type>::type;
+ using propagate_on_container_swap = typename __propagate_on_container_swap<allocator_type>::type;
+ using is_always_equal = typename __is_always_equal<allocator_type>::type;
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Tp>
+ using rebind_alloc = __allocator_traits_rebind_t<allocator_type, _Tp>;
+ template <class _Tp>
+ using rebind_traits = allocator_traits<rebind_alloc<_Tp> >;
+#else // _LIBCPP_CXX03_LANG
+ template <class _Tp>
+ struct rebind_alloc {
+ using other = __allocator_traits_rebind_t<allocator_type, _Tp>;
+ };
+ template <class _Tp>
+ struct rebind_traits {
+ using other = allocator_traits<typename rebind_alloc<_Tp>::other>;
+ };
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static pointer
+ allocate(allocator_type& __a, size_type __n) {
+ return __a.allocate(__n);
+ }
+
+ template <class _Ap = _Alloc, __enable_if_t<__has_allocate_hint<_Ap, size_type, const_void_pointer>::value, int> = 0>
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static pointer
+ allocate(allocator_type& __a, size_type __n, const_void_pointer __hint) {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ return __a.allocate(__n, __hint);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ }
+ template <class _Ap = _Alloc,
+ class = void,
+ __enable_if_t<!__has_allocate_hint<_Ap, size_type, const_void_pointer>::value, int> = 0>
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static pointer
+ allocate(allocator_type& __a, size_type __n, const_void_pointer) {
+ return __a.allocate(__n);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <class _Ap = _Alloc>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr allocation_result<pointer, size_type>
+ allocate_at_least(_Ap& __alloc, size_type __n) {
+ if constexpr (requires { __alloc.allocate_at_least(__n); }) {
+ return __alloc.allocate_at_least(__n);
+ } else {
+ return {__alloc.allocate(__n), __n};
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static void
+ deallocate(allocator_type& __a, pointer __p, size_type __n) _NOEXCEPT {
+ __a.deallocate(__p, __n);
+ }
+
+ template <class _Tp, class... _Args, __enable_if_t<__has_construct<allocator_type, _Tp*, _Args...>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static void
+ construct(allocator_type& __a, _Tp* __p, _Args&&... __args) {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ __a.construct(__p, std::forward<_Args>(__args)...);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ }
+ template <class _Tp,
+ class... _Args,
+ class = void,
+ __enable_if_t<!__has_construct<allocator_type, _Tp*, _Args...>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static void
+ construct(allocator_type&, _Tp* __p, _Args&&... __args) {
+ std::__construct_at(__p, std::forward<_Args>(__args)...);
+ }
+
+ template <class _Tp, __enable_if_t<__has_destroy<allocator_type, _Tp*>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static void destroy(allocator_type& __a, _Tp* __p) {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ __a.destroy(__p);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ }
+ template <class _Tp, class = void, __enable_if_t<!__has_destroy<allocator_type, _Tp*>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static void destroy(allocator_type&, _Tp* __p) {
+ std::__destroy_at(__p);
+ }
+
+ template <class _Ap = _Alloc, __enable_if_t<__has_max_size<const _Ap>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static size_type max_size(const allocator_type& __a) _NOEXCEPT {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ return __a.max_size();
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ }
+ template <class _Ap = _Alloc, class = void, __enable_if_t<!__has_max_size<const _Ap>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static size_type max_size(const allocator_type&) _NOEXCEPT {
+ return numeric_limits<size_type>::max() / sizeof(value_type);
+ }
+
+ template <class _Ap = _Alloc, __enable_if_t<__has_select_on_container_copy_construction<const _Ap>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static allocator_type
+ select_on_container_copy_construction(const allocator_type& __a) {
+ return __a.select_on_container_copy_construction();
+ }
+ template <class _Ap = _Alloc,
+ class = void,
+ __enable_if_t<!__has_select_on_container_copy_construction<const _Ap>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static allocator_type
+ select_on_container_copy_construction(const allocator_type& __a) {
+ return __a;
+ }
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Traits, class _Tp>
+using __rebind_alloc _LIBCPP_NODEBUG = typename _Traits::template rebind_alloc<_Tp>;
+#else
+template <class _Traits, class _Tp>
+using __rebind_alloc = typename _Traits::template rebind_alloc<_Tp>::other;
+#endif
+
+template <class _Alloc>
+struct __check_valid_allocator : true_type {
+ using _Traits = std::allocator_traits<_Alloc>;
+ static_assert(is_same<_Alloc, __rebind_alloc<_Traits, typename _Traits::value_type> >::value,
+ "[allocator.requirements] states that rebinding an allocator to the same type should result in the "
+ "original allocator");
+};
+
+// __is_default_allocator
+template <class _Tp>
+struct __is_default_allocator : false_type {};
+
+template <class>
+class allocator;
+
+template <class _Tp>
+struct __is_default_allocator<allocator<_Tp> > : true_type {};
+
+// __is_cpp17_move_insertable
+template <class _Alloc, class = void>
+struct __is_cpp17_move_insertable : is_move_constructible<typename _Alloc::value_type> {};
+
+template <class _Alloc>
+struct __is_cpp17_move_insertable<
+ _Alloc,
+ __enable_if_t< !__is_default_allocator<_Alloc>::value &&
+ __has_construct<_Alloc, typename _Alloc::value_type*, typename _Alloc::value_type&&>::value > >
+ : true_type {};
+
+// __is_cpp17_copy_insertable
+template <class _Alloc, class = void>
+struct __is_cpp17_copy_insertable
+ : integral_constant<bool,
+ is_copy_constructible<typename _Alloc::value_type>::value &&
+ __is_cpp17_move_insertable<_Alloc>::value > {};
+
+template <class _Alloc>
+struct __is_cpp17_copy_insertable<
+ _Alloc,
+ __enable_if_t< !__is_default_allocator<_Alloc>::value &&
+ __has_construct<_Alloc, typename _Alloc::value_type*, const typename _Alloc::value_type&>::value > >
+ : __is_cpp17_move_insertable<_Alloc> {};
+
+#undef _LIBCPP_ALLOCATOR_TRAITS_HAS_XXX
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_ALLOCATOR_TRAITS_H
diff --git a/libcxx/include/__cxx03/__memory/assume_aligned.h b/libcxx/include/__cxx03/__memory/assume_aligned.h
new file mode 100644
index 00000000000000..526eb3334f958c
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/assume_aligned.h
@@ -0,0 +1,50 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_ASSUME_ALIGNED_H
+#define _LIBCPP___MEMORY_ASSUME_ALIGNED_H
+
+#include <__assert>
+#include <__config>
+#include <__type_traits/is_constant_evaluated.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t _Np, class _Tp>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp* __assume_aligned(_Tp* __ptr) {
+ static_assert(_Np != 0 && (_Np & (_Np - 1)) == 0, "std::assume_aligned<N>(p) requires N to be a power of two");
+
+ if (__libcpp_is_constant_evaluated()) {
+ (void)__builtin_assume_aligned(__ptr, _Np);
+ return __ptr;
+ } else {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ reinterpret_cast<uintptr_t>(__ptr) % _Np == 0, "Alignment assumption is violated");
+ return static_cast<_Tp*>(__builtin_assume_aligned(__ptr, _Np));
+ }
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <size_t _Np, class _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp* assume_aligned(_Tp* __ptr) {
+ return std::__assume_aligned<_Np>(__ptr);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_ASSUME_ALIGNED_H
diff --git a/libcxx/include/__cxx03/__memory/auto_ptr.h b/libcxx/include/__cxx03/__memory/auto_ptr.h
new file mode 100644
index 00000000000000..752143616bb20b
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/auto_ptr.h
@@ -0,0 +1,92 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_AUTO_PTR_H
+#define _LIBCPP___MEMORY_AUTO_PTR_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr_ref {
+ _Tp* __ptr_;
+};
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr {
+private:
+ _Tp* __ptr_;
+
+public:
+ typedef _Tp element_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit auto_ptr(_Tp* __p = 0) _NOEXCEPT : __ptr_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI auto_ptr(auto_ptr& __p) _NOEXCEPT : __ptr_(__p.release()) {}
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI auto_ptr(auto_ptr<_Up>& __p) _NOEXCEPT : __ptr_(__p.release()) {}
+ _LIBCPP_HIDE_FROM_ABI auto_ptr& operator=(auto_ptr& __p) _NOEXCEPT {
+ reset(__p.release());
+ return *this;
+ }
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI auto_ptr& operator=(auto_ptr<_Up>& __p) _NOEXCEPT {
+ reset(__p.release());
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI auto_ptr& operator=(auto_ptr_ref<_Tp> __p) _NOEXCEPT {
+ reset(__p.__ptr_);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI ~auto_ptr() _NOEXCEPT { delete __ptr_; }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp& operator*() const _NOEXCEPT { return *__ptr_; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator->() const _NOEXCEPT { return __ptr_; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* get() const _NOEXCEPT { return __ptr_; }
+ _LIBCPP_HIDE_FROM_ABI _Tp* release() _NOEXCEPT {
+ _Tp* __t = __ptr_;
+ __ptr_ = nullptr;
+ return __t;
+ }
+ _LIBCPP_HIDE_FROM_ABI void reset(_Tp* __p = 0) _NOEXCEPT {
+ if (__ptr_ != __p)
+ delete __ptr_;
+ __ptr_ = __p;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI auto_ptr(auto_ptr_ref<_Tp> __p) _NOEXCEPT : __ptr_(__p.__ptr_) {}
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI operator auto_ptr_ref<_Up>() _NOEXCEPT {
+ auto_ptr_ref<_Up> __t;
+ __t.__ptr_ = release();
+ return __t;
+ }
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI operator auto_ptr<_Up>() _NOEXCEPT {
+ return auto_ptr<_Up>(release());
+ }
+};
+
+template <>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr<void> {
+public:
+ typedef void element_type;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
+
+#endif // _LIBCPP___MEMORY_AUTO_PTR_H
diff --git a/libcxx/include/__cxx03/__memory/builtin_new_allocator.h b/libcxx/include/__cxx03/__memory/builtin_new_allocator.h
new file mode 100644
index 00000000000000..c6f7f3c5ff52a1
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/builtin_new_allocator.h
@@ -0,0 +1,67 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_BUILTIN_NEW_ALLOCATOR_H
+#define _LIBCPP___MEMORY_BUILTIN_NEW_ALLOCATOR_H
+
+#include <__config>
+#include <__memory/unique_ptr.h>
+#include <cstddef>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// __builtin_new_allocator -- A non-templated helper for allocating and
+// deallocating memory using __builtin_operator_new and
+// __builtin_operator_delete. It should be used in preference to
+// `std::allocator<T>` to avoid additional instantiations.
+struct __builtin_new_allocator {
+ struct __builtin_new_deleter {
+ typedef void* pointer_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __builtin_new_deleter(size_t __size, size_t __align)
+ : __size_(__size), __align_(__align) {}
+
+ _LIBCPP_HIDE_FROM_ABI void operator()(void* __p) const _NOEXCEPT {
+ std::__libcpp_deallocate(__p, __size_, __align_);
+ }
+
+ private:
+ size_t __size_;
+ size_t __align_;
+ };
+
+ typedef unique_ptr<void, __builtin_new_deleter> __holder_t;
+
+ _LIBCPP_HIDE_FROM_ABI static __holder_t __allocate_bytes(size_t __s, size_t __align) {
+ return __holder_t(std::__libcpp_allocate(__s, __align), __builtin_new_deleter(__s, __align));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void __deallocate_bytes(void* __p, size_t __s, size_t __align) _NOEXCEPT {
+ std::__libcpp_deallocate(__p, __s, __align);
+ }
+
+ template <class _Tp>
+ _LIBCPP_NODEBUG _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI static __holder_t __allocate_type(size_t __n) {
+ return __allocate_bytes(__n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));
+ }
+
+ template <class _Tp>
+ _LIBCPP_NODEBUG _LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI static void
+ __deallocate_type(void* __p, size_t __n) _NOEXCEPT {
+ __deallocate_bytes(__p, __n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_BUILTIN_NEW_ALLOCATOR_H
diff --git a/libcxx/include/__cxx03/__memory/compressed_pair.h b/libcxx/include/__cxx03/__memory/compressed_pair.h
new file mode 100644
index 00000000000000..40e5cfc35fb040
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/compressed_pair.h
@@ -0,0 +1,171 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_COMPRESSED_PAIR_H
+#define _LIBCPP___MEMORY_COMPRESSED_PAIR_H
+
+#include <__config>
+#include <__fwd/tuple.h>
+#include <__tuple/tuple_indices.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/dependent_type.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_empty.h>
+#include <__type_traits/is_final.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/piecewise_construct.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Tag used to default initialize one or both of the pair's elements.
+struct __default_init_tag {};
+struct __value_init_tag {};
+
+template <class _Tp, int _Idx, bool _CanBeEmptyBase = is_empty<_Tp>::value && !__libcpp_is_final<_Tp>::value>
+struct __compressed_pair_elem {
+ using _ParamT = _Tp;
+ using reference = _Tp&;
+ using const_reference = const _Tp&;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair_elem(__default_init_tag) {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair_elem(__value_init_tag) : __value_() {}
+
+ template <class _Up, __enable_if_t<!is_same<__compressed_pair_elem, __decay_t<_Up> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair_elem(_Up&& __u)
+ : __value_(std::forward<_Up>(__u)) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args, size_t... _Indices>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 explicit __compressed_pair_elem(
+ piecewise_construct_t, tuple<_Args...> __args, __tuple_indices<_Indices...>)
+ : __value_(std::forward<_Args>(std::get<_Indices>(__args))...) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference __get() _NOEXCEPT { return __value_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference __get() const _NOEXCEPT { return __value_; }
+
+private:
+ _Tp __value_;
+};
+
+template <class _Tp, int _Idx>
+struct __compressed_pair_elem<_Tp, _Idx, true> : private _Tp {
+ using _ParamT = _Tp;
+ using reference = _Tp&;
+ using const_reference = const _Tp&;
+ using __value_type = _Tp;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair_elem() = default;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair_elem(__default_init_tag) {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair_elem(__value_init_tag) : __value_type() {}
+
+ template <class _Up, __enable_if_t<!is_same<__compressed_pair_elem, __decay_t<_Up> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair_elem(_Up&& __u)
+ : __value_type(std::forward<_Up>(__u)) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args, size_t... _Indices>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17
+ __compressed_pair_elem(piecewise_construct_t, tuple<_Args...> __args, __tuple_indices<_Indices...>)
+ : __value_type(std::forward<_Args>(std::get<_Indices>(__args))...) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference __get() _NOEXCEPT { return *this; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference __get() const _NOEXCEPT { return *this; }
+};
+
+template <class _T1, class _T2>
+class __compressed_pair : private __compressed_pair_elem<_T1, 0>, private __compressed_pair_elem<_T2, 1> {
+public:
+ // NOTE: This static assert should never fire because __compressed_pair
+ // is *almost never* used in a scenario where it's possible for T1 == T2.
+ // (The exception is std::function where it is possible that the function
+ // object and the allocator have the same type).
+ static_assert(
+ (!is_same<_T1, _T2>::value),
+ "__compressed_pair cannot be instantiated when T1 and T2 are the same type; "
+ "The current implementation is NOT ABI-compatible with the previous implementation for this configuration");
+
+ using _Base1 _LIBCPP_NODEBUG = __compressed_pair_elem<_T1, 0>;
+ using _Base2 _LIBCPP_NODEBUG = __compressed_pair_elem<_T2, 1>;
+
+ template <bool _Dummy = true,
+ __enable_if_t< __dependent_type<is_default_constructible<_T1>, _Dummy>::value &&
+ __dependent_type<is_default_constructible<_T2>, _Dummy>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair()
+ : _Base1(__value_init_tag()), _Base2(__value_init_tag()) {}
+
+ template <class _U1, class _U2>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __compressed_pair(_U1&& __t1, _U2&& __t2)
+ : _Base1(std::forward<_U1>(__t1)), _Base2(std::forward<_U2>(__t2)) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args1, class... _Args2>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 explicit __compressed_pair(
+ piecewise_construct_t __pc, tuple<_Args1...> __first_args, tuple<_Args2...> __second_args)
+ : _Base1(__pc, std::move(__first_args), typename __make_tuple_indices<sizeof...(_Args1)>::type()),
+ _Base2(__pc, std::move(__second_args), typename __make_tuple_indices<sizeof...(_Args2)>::type()) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename _Base1::reference first() _NOEXCEPT {
+ return static_cast<_Base1&>(*this).__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR typename _Base1::const_reference first() const _NOEXCEPT {
+ return static_cast<_Base1 const&>(*this).__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename _Base2::reference second() _NOEXCEPT {
+ return static_cast<_Base2&>(*this).__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR typename _Base2::const_reference second() const _NOEXCEPT {
+ return static_cast<_Base2 const&>(*this).__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR static _Base1* __get_first_base(__compressed_pair* __pair) _NOEXCEPT {
+ return static_cast<_Base1*>(__pair);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR static _Base2* __get_second_base(__compressed_pair* __pair) _NOEXCEPT {
+ return static_cast<_Base2*>(__pair);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void swap(__compressed_pair& __x)
+ _NOEXCEPT_(__is_nothrow_swappable_v<_T1>&& __is_nothrow_swappable_v<_T2>) {
+ using std::swap;
+ swap(first(), __x.first());
+ swap(second(), __x.second());
+ }
+};
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
+ _NOEXCEPT_(__is_nothrow_swappable_v<_T1>&& __is_nothrow_swappable_v<_T2>) {
+ __x.swap(__y);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_COMPRESSED_PAIR_H
diff --git a/libcxx/include/__cxx03/__memory/concepts.h b/libcxx/include/__cxx03/__memory/concepts.h
new file mode 100644
index 00000000000000..216144aad74805
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/concepts.h
@@ -0,0 +1,63 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_CONCEPTS_H
+#define _LIBCPP___MEMORY_CONCEPTS_H
+
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h> // TODO(modules): This should not be required
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+// [special.mem.concepts]
+
+// This concept ensures that uninitialized algorithms can construct an object
+// at the address pointed-to by the iterator, which requires an lvalue.
+template <class _Ip>
+concept __nothrow_input_iterator =
+ input_iterator<_Ip> && is_lvalue_reference_v<iter_reference_t<_Ip>> &&
+ same_as<remove_cvref_t<iter_reference_t<_Ip>>, iter_value_t<_Ip>>;
+
+template <class _Sp, class _Ip>
+concept __nothrow_sentinel_for = sentinel_for<_Sp, _Ip>;
+
+template <class _Rp>
+concept __nothrow_input_range =
+ range<_Rp> && __nothrow_input_iterator<iterator_t<_Rp>> && __nothrow_sentinel_for<sentinel_t<_Rp>, iterator_t<_Rp>>;
+
+template <class _Ip>
+concept __nothrow_forward_iterator =
+ __nothrow_input_iterator<_Ip> && forward_iterator<_Ip> && __nothrow_sentinel_for<_Ip, _Ip>;
+
+template <class _Rp>
+concept __nothrow_forward_range = __nothrow_input_range<_Rp> && __nothrow_forward_iterator<iterator_t<_Rp>>;
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_CONCEPTS_H
diff --git a/libcxx/include/__cxx03/__memory/construct_at.h b/libcxx/include/__cxx03/__memory/construct_at.h
new file mode 100644
index 00000000000000..eb021324800644
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/construct_at.h
@@ -0,0 +1,128 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_CONSTRUCT_AT_H
+#define _LIBCPP___MEMORY_CONSTRUCT_AT_H
+
+#include <__assert>
+#include <__config>
+#include <__iterator/access.h>
+#include <__memory/addressof.h>
+#include <__memory/voidify.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_array.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// construct_at
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp, class... _Args, class = decltype(::new(std::declval<void*>()) _Tp(std::declval<_Args>()...))>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp* construct_at(_Tp* __location, _Args&&... __args) {
+ _LIBCPP_ASSERT_NON_NULL(__location != nullptr, "null pointer given to construct_at");
+ return ::new (std::__voidify(*__location)) _Tp(std::forward<_Args>(__args)...);
+}
+
+#endif
+
+template <class _Tp, class... _Args, class = decltype(::new(std::declval<void*>()) _Tp(std::declval<_Args>()...))>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp* __construct_at(_Tp* __location, _Args&&... __args) {
+#if _LIBCPP_STD_VER >= 20
+ return std::construct_at(__location, std::forward<_Args>(__args)...);
+#else
+ return _LIBCPP_ASSERT_NON_NULL(__location != nullptr, "null pointer given to construct_at"),
+ ::new (std::__voidify(*__location)) _Tp(std::forward<_Args>(__args)...);
+#endif
+}
+
+// destroy_at
+
+// The internal functions are available regardless of the language version (with the exception of the `__destroy_at`
+// taking an array).
+
+template <class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator __destroy(_ForwardIterator, _ForwardIterator);
+
+template <class _Tp, __enable_if_t<!is_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __destroy_at(_Tp* __loc) {
+ _LIBCPP_ASSERT_NON_NULL(__loc != nullptr, "null pointer given to destroy_at");
+ __loc->~_Tp();
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, __enable_if_t<is_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __destroy_at(_Tp* __loc) {
+ _LIBCPP_ASSERT_NON_NULL(__loc != nullptr, "null pointer given to destroy_at");
+ std::__destroy(std::begin(*__loc), std::end(*__loc));
+}
+#endif
+
+template <class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
+__destroy(_ForwardIterator __first, _ForwardIterator __last) {
+ for (; __first != __last; ++__first)
+ std::__destroy_at(std::addressof(*__first));
+ return __first;
+}
+
+template <class _BidirectionalIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _BidirectionalIterator
+__reverse_destroy(_BidirectionalIterator __first, _BidirectionalIterator __last) {
+ while (__last != __first) {
+ --__last;
+ std::__destroy_at(std::addressof(*__last));
+ }
+ return __last;
+}
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Tp, enable_if_t<!is_array_v<_Tp>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void destroy_at(_Tp* __loc) {
+ std::__destroy_at(__loc);
+}
+
+# if _LIBCPP_STD_VER >= 20
+template <class _Tp, enable_if_t<is_array_v<_Tp>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void destroy_at(_Tp* __loc) {
+ std::__destroy_at(__loc);
+}
+# endif
+
+template <class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void destroy(_ForwardIterator __first, _ForwardIterator __last) {
+ (void)std::__destroy(std::move(__first), std::move(__last));
+}
+
+template <class _ForwardIterator, class _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator destroy_n(_ForwardIterator __first, _Size __n) {
+ for (; __n > 0; (void)++__first, --__n)
+ std::__destroy_at(std::addressof(*__first));
+ return __first;
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_CONSTRUCT_AT_H
diff --git a/libcxx/include/__cxx03/__memory/destruct_n.h b/libcxx/include/__cxx03/__memory/destruct_n.h
new file mode 100644
index 00000000000000..78635ad0af04bd
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/destruct_n.h
@@ -0,0 +1,63 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_DESTRUCT_N_H
+#define _LIBCPP___MEMORY_DESTRUCT_N_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __destruct_n {
+private:
+ size_t __size_;
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI void __process(_Tp* __p, false_type) _NOEXCEPT {
+ for (size_t __i = 0; __i < __size_; ++__i, ++__p)
+ __p->~_Tp();
+ }
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI void __process(_Tp*, true_type) _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI void __incr(false_type) _NOEXCEPT { ++__size_; }
+ _LIBCPP_HIDE_FROM_ABI void __incr(true_type) _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI void __set(size_t __s, false_type) _NOEXCEPT { __size_ = __s; }
+ _LIBCPP_HIDE_FROM_ABI void __set(size_t, true_type) _NOEXCEPT {}
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __destruct_n(size_t __s) _NOEXCEPT : __size_(__s) {}
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI void __incr() _NOEXCEPT {
+ __incr(integral_constant<bool, is_trivially_destructible<_Tp>::value>());
+ }
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI void __set(size_t __s, _Tp*) _NOEXCEPT {
+ __set(__s, integral_constant<bool, is_trivially_destructible<_Tp>::value>());
+ }
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI void operator()(_Tp* __p) _NOEXCEPT {
+ __process(__p, integral_constant<bool, is_trivially_destructible<_Tp>::value>());
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_DESTRUCT_N_H
diff --git a/libcxx/include/__cxx03/__memory/inout_ptr.h b/libcxx/include/__cxx03/__memory/inout_ptr.h
new file mode 100644
index 00000000000000..e5f3ac5d027e8e
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/inout_ptr.h
@@ -0,0 +1,109 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___INOUT_PTR_H
+#define _LIBCPP___INOUT_PTR_H
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/shared_ptr.h>
+#include <__memory/unique_ptr.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_specialization.h>
+#include <__type_traits/is_void.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Smart, class _Pointer, class... _Args>
+class _LIBCPP_TEMPLATE_VIS inout_ptr_t {
+ static_assert(!__is_specialization_v<_Smart, shared_ptr>, "std::shared_ptr<> is not supported with std::inout_ptr.");
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit inout_ptr_t(_Smart& __smart, _Args... __args)
+ : __s_(__smart), __a_(std::forward<_Args>(__args)...), __p_([&__smart] {
+ if constexpr (is_pointer_v<_Smart>) {
+ return __smart;
+ } else {
+ return __smart.get();
+ }
+ }()) {
+ if constexpr (requires { __s_.release(); }) {
+ __s_.release();
+ } else {
+ __s_ = _Smart();
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI inout_ptr_t(const inout_ptr_t&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI ~inout_ptr_t() {
+ // LWG-3897 inout_ptr will not update raw pointer to null
+ if constexpr (!is_pointer_v<_Smart>) {
+ if (!__p_) {
+ return;
+ }
+ }
+
+ using _SmartPtr = __pointer_of_or_t<_Smart, _Pointer>;
+ if constexpr (is_pointer_v<_Smart>) {
+ std::apply([&](auto&&... __args) { __s_ = _Smart(static_cast<_SmartPtr>(__p_), std::forward<_Args>(__args)...); },
+ std::move(__a_));
+ } else if constexpr (__resettable_smart_pointer_with_args<_Smart, _Pointer, _Args...>) {
+ std::apply([&](auto&&... __args) { __s_.reset(static_cast<_SmartPtr>(__p_), std::forward<_Args>(__args)...); },
+ std::move(__a_));
+ } else {
+ static_assert(is_constructible_v<_Smart, _SmartPtr, _Args...>,
+ "The smart pointer must be constructible from arguments of types _Smart, _Pointer, _Args...");
+ std::apply([&](auto&&... __args) { __s_ = _Smart(static_cast<_SmartPtr>(__p_), std::forward<_Args>(__args)...); },
+ std::move(__a_));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI operator _Pointer*() const noexcept { return std::addressof(const_cast<_Pointer&>(__p_)); }
+
+ _LIBCPP_HIDE_FROM_ABI operator void**() const noexcept
+ requires(!is_same_v<_Pointer, void*>)
+ {
+ static_assert(is_pointer_v<_Pointer>, "The conversion to void** requires _Pointer to be a raw pointer.");
+
+ return reinterpret_cast<void**>(static_cast<_Pointer*>(*this));
+ }
+
+private:
+ _Smart& __s_;
+ tuple<_Args...> __a_;
+ _Pointer __p_;
+};
+
+template <class _Pointer = void, class _Smart, class... _Args>
+_LIBCPP_HIDE_FROM_ABI auto inout_ptr(_Smart& __s, _Args&&... __args) {
+ using _Ptr = conditional_t<is_void_v<_Pointer>, __pointer_of_t<_Smart>, _Pointer>;
+ return std::inout_ptr_t<_Smart, _Ptr, _Args&&...>(__s, std::forward<_Args>(__args)...);
+}
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___INOUT_PTR_H
diff --git a/libcxx/include/__cxx03/__memory/out_ptr.h b/libcxx/include/__cxx03/__memory/out_ptr.h
new file mode 100644
index 00000000000000..fd99110790cc89
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/out_ptr.h
@@ -0,0 +1,101 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___OUT_PTR_H
+#define _LIBCPP___OUT_PTR_H
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/shared_ptr.h>
+#include <__memory/unique_ptr.h>
+#include <__type_traits/is_specialization.h>
+#include <__type_traits/is_void.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Smart, class _Pointer, class... _Args>
+class _LIBCPP_TEMPLATE_VIS out_ptr_t {
+ static_assert(!__is_specialization_v<_Smart, shared_ptr> || sizeof...(_Args) > 0,
+ "Using std::shared_ptr<> without a deleter in std::out_ptr is not supported.");
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit out_ptr_t(_Smart& __smart, _Args... __args)
+ : __s_(__smart), __a_(std::forward<_Args>(__args)...), __p_() {
+ using _Ptr = decltype(__smart);
+ if constexpr (__resettable_smart_pointer<_Ptr>) {
+ __s_.reset();
+ } else if constexpr (is_constructible_v<_Smart>) {
+ __s_ = _Smart();
+ } else {
+ static_assert(__resettable_smart_pointer<_Ptr> || is_constructible_v<_Smart>,
+ "The adapted pointer type must have a reset() member function or be default constructible.");
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI out_ptr_t(const out_ptr_t&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI ~out_ptr_t() {
+ if (!__p_) {
+ return;
+ }
+
+ using _SmartPtr = __pointer_of_or_t<_Smart, _Pointer>;
+ if constexpr (__resettable_smart_pointer_with_args<_Smart, _Pointer, _Args...>) {
+ std::apply([&](auto&&... __args) { __s_.reset(static_cast<_SmartPtr>(__p_), std::forward<_Args>(__args)...); },
+ std::move(__a_));
+ } else {
+ static_assert(is_constructible_v<_Smart, _SmartPtr, _Args...>,
+ "The smart pointer must be constructible from arguments of types _Smart, _Pointer, _Args...");
+ std::apply([&](auto&&... __args) { __s_ = _Smart(static_cast<_SmartPtr>(__p_), std::forward<_Args>(__args)...); },
+ std::move(__a_));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI operator _Pointer*() const noexcept { return std::addressof(const_cast<_Pointer&>(__p_)); }
+
+ _LIBCPP_HIDE_FROM_ABI operator void**() const noexcept
+ requires(!is_same_v<_Pointer, void*>)
+ {
+ static_assert(is_pointer_v<_Pointer>, "The conversion to void** requires _Pointer to be a raw pointer.");
+
+ return reinterpret_cast<void**>(static_cast<_Pointer*>(*this));
+ }
+
+private:
+ _Smart& __s_;
+ tuple<_Args...> __a_;
+ _Pointer __p_ = _Pointer();
+};
+
+template <class _Pointer = void, class _Smart, class... _Args>
+_LIBCPP_HIDE_FROM_ABI auto out_ptr(_Smart& __s, _Args&&... __args) {
+ using _Ptr = conditional_t<is_void_v<_Pointer>, __pointer_of_t<_Smart>, _Pointer>;
+ return std::out_ptr_t<_Smart, _Ptr, _Args&&...>(__s, std::forward<_Args>(__args)...);
+}
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___OUT_PTR_H
diff --git a/libcxx/include/__cxx03/__memory/pointer_traits.h b/libcxx/include/__cxx03/__memory/pointer_traits.h
new file mode 100644
index 00000000000000..0914aceb318b74
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/pointer_traits.h
@@ -0,0 +1,307 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_POINTER_TRAITS_H
+#define _LIBCPP___MEMORY_POINTER_TRAITS_H
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_class.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// clang-format off
+#define _LIBCPP_CLASS_TRAITS_HAS_XXX(NAME, PROPERTY) \
+ template <class _Tp, class = void> \
+ struct NAME : false_type {}; \
+ template <class _Tp> \
+ struct NAME<_Tp, __void_t<typename _Tp::PROPERTY> > : true_type {}
+// clang-format on
+
+_LIBCPP_CLASS_TRAITS_HAS_XXX(__has_pointer, pointer);
+_LIBCPP_CLASS_TRAITS_HAS_XXX(__has_element_type, element_type);
+
+template <class _Ptr, bool = __has_element_type<_Ptr>::value>
+struct __pointer_traits_element_type {};
+
+template <class _Ptr>
+struct __pointer_traits_element_type<_Ptr, true> {
+ typedef _LIBCPP_NODEBUG typename _Ptr::element_type type;
+};
+
+template <template <class, class...> class _Sp, class _Tp, class... _Args>
+struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, true> {
+ typedef _LIBCPP_NODEBUG typename _Sp<_Tp, _Args...>::element_type type;
+};
+
+template <template <class, class...> class _Sp, class _Tp, class... _Args>
+struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, false> {
+ typedef _LIBCPP_NODEBUG _Tp type;
+};
+
+template <class _Tp, class = void>
+struct __has_difference_type : false_type {};
+
+template <class _Tp>
+struct __has_difference_type<_Tp, __void_t<typename _Tp::difference_type> > : true_type {};
+
+template <class _Ptr, bool = __has_difference_type<_Ptr>::value>
+struct __pointer_traits_difference_type {
+ typedef _LIBCPP_NODEBUG ptrdiff_t type;
+};
+
+template <class _Ptr>
+struct __pointer_traits_difference_type<_Ptr, true> {
+ typedef _LIBCPP_NODEBUG typename _Ptr::difference_type type;
+};
+
+template <class _Tp, class _Up>
+struct __has_rebind {
+private:
+ template <class _Xp>
+ static false_type __test(...);
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ template <class _Xp>
+ static true_type __test(typename _Xp::template rebind<_Up>* = 0);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ static const bool value = decltype(__test<_Tp>(0))::value;
+};
+
+template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
+struct __pointer_traits_rebind {
+#ifndef _LIBCPP_CXX03_LANG
+ typedef _LIBCPP_NODEBUG typename _Tp::template rebind<_Up> type;
+#else
+ typedef _LIBCPP_NODEBUG typename _Tp::template rebind<_Up>::other type;
+#endif
+};
+
+template <template <class, class...> class _Sp, class _Tp, class... _Args, class _Up>
+struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, true> {
+#ifndef _LIBCPP_CXX03_LANG
+ typedef _LIBCPP_NODEBUG typename _Sp<_Tp, _Args...>::template rebind<_Up> type;
+#else
+ typedef _LIBCPP_NODEBUG typename _Sp<_Tp, _Args...>::template rebind<_Up>::other type;
+#endif
+};
+
+template <template <class, class...> class _Sp, class _Tp, class... _Args, class _Up>
+struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, false> {
+ typedef _Sp<_Up, _Args...> type;
+};
+
+template <class _Ptr, class = void>
+struct __pointer_traits_impl {};
+
+template <class _Ptr>
+struct __pointer_traits_impl<_Ptr, __void_t<typename __pointer_traits_element_type<_Ptr>::type> > {
+ typedef _Ptr pointer;
+ typedef typename __pointer_traits_element_type<pointer>::type element_type;
+ typedef typename __pointer_traits_difference_type<pointer>::type difference_type;
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Up>
+ using rebind = typename __pointer_traits_rebind<pointer, _Up>::type;
+#else
+ template <class _Up>
+ struct rebind {
+ typedef typename __pointer_traits_rebind<pointer, _Up>::type other;
+ };
+#endif // _LIBCPP_CXX03_LANG
+
+private:
+ struct __nat {};
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static pointer
+ pointer_to(__conditional_t<is_void<element_type>::value, __nat, element_type>& __r) {
+ return pointer::pointer_to(__r);
+ }
+};
+
+template <class _Ptr>
+struct _LIBCPP_TEMPLATE_VIS pointer_traits : __pointer_traits_impl<_Ptr> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS pointer_traits<_Tp*> {
+ typedef _Tp* pointer;
+ typedef _Tp element_type;
+ typedef ptrdiff_t difference_type;
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Up>
+ using rebind = _Up*;
+#else
+ template <class _Up>
+ struct rebind {
+ typedef _Up* other;
+ };
+#endif
+
+private:
+ struct __nat {};
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static pointer
+ pointer_to(__conditional_t<is_void<element_type>::value, __nat, element_type>& __r) _NOEXCEPT {
+ return std::addressof(__r);
+ }
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _From, class _To>
+using __rebind_pointer_t = typename pointer_traits<_From>::template rebind<_To>;
+#else
+template <class _From, class _To>
+using __rebind_pointer_t = typename pointer_traits<_From>::template rebind<_To>::other;
+#endif
+
+// to_address
+
+template <class _Pointer, class = void>
+struct __to_address_helper;
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp* __to_address(_Tp* __p) _NOEXCEPT {
+ static_assert(!is_function<_Tp>::value, "_Tp is a function type");
+ return __p;
+}
+
+template <class _Pointer, class = void>
+struct _HasToAddress : false_type {};
+
+template <class _Pointer>
+struct _HasToAddress<_Pointer, decltype((void)pointer_traits<_Pointer>::to_address(std::declval<const _Pointer&>())) >
+ : true_type {};
+
+template <class _Pointer, class = void>
+struct _HasArrow : false_type {};
+
+template <class _Pointer>
+struct _HasArrow<_Pointer, decltype((void)std::declval<const _Pointer&>().operator->()) > : true_type {};
+
+template <class _Pointer>
+struct _IsFancyPointer {
+ static const bool value = _HasArrow<_Pointer>::value || _HasToAddress<_Pointer>::value;
+};
+
+// enable_if is needed here to avoid instantiating checks for fancy pointers on raw pointers
+template <class _Pointer, __enable_if_t< _And<is_class<_Pointer>, _IsFancyPointer<_Pointer> >::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR __decay_t<decltype(__to_address_helper<_Pointer>::__call(std::declval<const _Pointer&>()))>
+__to_address(const _Pointer& __p) _NOEXCEPT {
+ return __to_address_helper<_Pointer>::__call(__p);
+}
+
+template <class _Pointer, class>
+struct __to_address_helper {
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR static decltype(std::__to_address(std::declval<const _Pointer&>().operator->()))
+ __call(const _Pointer& __p) _NOEXCEPT {
+ return std::__to_address(__p.operator->());
+ }
+};
+
+template <class _Pointer>
+struct __to_address_helper<_Pointer,
+ decltype((void)pointer_traits<_Pointer>::to_address(std::declval<const _Pointer&>()))> {
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR static decltype(pointer_traits<_Pointer>::to_address(std::declval<const _Pointer&>()))
+ __call(const _Pointer& __p) _NOEXCEPT {
+ return pointer_traits<_Pointer>::to_address(__p);
+ }
+};
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI constexpr auto to_address(_Tp* __p) noexcept {
+ return std::__to_address(__p);
+}
+
+template <class _Pointer>
+inline _LIBCPP_HIDE_FROM_ABI constexpr auto
+to_address(const _Pointer& __p) noexcept -> decltype(std::__to_address(__p)) {
+ return std::__to_address(__p);
+}
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Tp>
+struct __pointer_of {};
+
+template <class _Tp>
+ requires(__has_pointer<_Tp>::value)
+struct __pointer_of<_Tp> {
+ using type = typename _Tp::pointer;
+};
+
+template <class _Tp>
+ requires(!__has_pointer<_Tp>::value && __has_element_type<_Tp>::value)
+struct __pointer_of<_Tp> {
+ using type = typename _Tp::element_type*;
+};
+
+template <class _Tp>
+ requires(!__has_pointer<_Tp>::value && !__has_element_type<_Tp>::value &&
+ __has_element_type<pointer_traits<_Tp>>::value)
+struct __pointer_of<_Tp> {
+ using type = typename pointer_traits<_Tp>::element_type*;
+};
+
+template <typename _Tp>
+using __pointer_of_t = typename __pointer_of<_Tp>::type;
+
+template <class _Tp, class _Up>
+struct __pointer_of_or {
+ using type _LIBCPP_NODEBUG = _Up;
+};
+
+template <class _Tp, class _Up>
+ requires requires { typename __pointer_of_t<_Tp>; }
+struct __pointer_of_or<_Tp, _Up> {
+ using type _LIBCPP_NODEBUG = __pointer_of_t<_Tp>;
+};
+
+template <typename _Tp, typename _Up>
+using __pointer_of_or_t = typename __pointer_of_or<_Tp, _Up>::type;
+
+template <class _Smart>
+concept __resettable_smart_pointer = requires(_Smart __s) { __s.reset(); };
+
+template <class _Smart, class _Pointer, class... _Args>
+concept __resettable_smart_pointer_with_args = requires(_Smart __s, _Pointer __p, _Args... __args) {
+ __s.reset(static_cast<__pointer_of_or_t<_Smart, _Pointer>>(__p), std::forward<_Args>(__args)...);
+};
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_POINTER_TRAITS_H
diff --git a/libcxx/include/__cxx03/__memory/ranges_construct_at.h b/libcxx/include/__cxx03/__memory/ranges_construct_at.h
new file mode 100644
index 00000000000000..f731e75e7bdc0d
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/ranges_construct_at.h
@@ -0,0 +1,124 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RANGES_CONSTRUCT_AT_H
+#define _LIBCPP___MEMORY_RANGES_CONSTRUCT_AT_H
+
+#include <__concepts/destructible.h>
+#include <__config>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/concepts.h>
+#include <__memory/construct_at.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+namespace ranges {
+
+// construct_at
+
+namespace __construct_at {
+
+struct __fn {
+ template <class _Tp, class... _Args, class = decltype(::new(std::declval<void*>()) _Tp(std::declval<_Args>()...))>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* operator()(_Tp* __location, _Args&&... __args) const {
+ return std::construct_at(__location, std::forward<_Args>(__args)...);
+ }
+};
+
+} // namespace __construct_at
+
+inline namespace __cpo {
+inline constexpr auto construct_at = __construct_at::__fn{};
+} // namespace __cpo
+
+// destroy_at
+
+namespace __destroy_at {
+
+struct __fn {
+ template <destructible _Tp>
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator()(_Tp* __location) const noexcept {
+ std::destroy_at(__location);
+ }
+};
+
+} // namespace __destroy_at
+
+inline namespace __cpo {
+inline constexpr auto destroy_at = __destroy_at::__fn{};
+} // namespace __cpo
+
+// destroy
+
+namespace __destroy {
+
+struct __fn {
+ template <__nothrow_input_iterator _InputIterator, __nothrow_sentinel_for<_InputIterator> _Sentinel>
+ requires destructible<iter_value_t<_InputIterator>>
+ _LIBCPP_HIDE_FROM_ABI constexpr _InputIterator operator()(_InputIterator __first, _Sentinel __last) const noexcept {
+ return std::__destroy(std::move(__first), std::move(__last));
+ }
+
+ template <__nothrow_input_range _InputRange>
+ requires destructible<range_value_t<_InputRange>>
+ _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_InputRange> operator()(_InputRange&& __range) const noexcept {
+ return (*this)(ranges::begin(__range), ranges::end(__range));
+ }
+};
+
+} // namespace __destroy
+
+inline namespace __cpo {
+inline constexpr auto destroy = __destroy::__fn{};
+} // namespace __cpo
+
+// destroy_n
+
+namespace __destroy_n {
+
+struct __fn {
+ template <__nothrow_input_iterator _InputIterator>
+ requires destructible<iter_value_t<_InputIterator>>
+ _LIBCPP_HIDE_FROM_ABI constexpr _InputIterator
+ operator()(_InputIterator __first, iter_difference_t<_InputIterator> __n) const noexcept {
+ return std::destroy_n(std::move(__first), __n);
+ }
+};
+
+} // namespace __destroy_n
+
+inline namespace __cpo {
+inline constexpr auto destroy_n = __destroy_n::__fn{};
+} // namespace __cpo
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_RANGES_CONSTRUCT_AT_H
diff --git a/libcxx/include/__cxx03/__memory/ranges_uninitialized_algorithms.h b/libcxx/include/__cxx03/__memory/ranges_uninitialized_algorithms.h
new file mode 100644
index 00000000000000..90090055bbbbf9
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/ranges_uninitialized_algorithms.h
@@ -0,0 +1,325 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RANGES_UNINITIALIZED_ALGORITHMS_H
+#define _LIBCPP___MEMORY_RANGES_UNINITIALIZED_ALGORITHMS_H
+
+#include <__algorithm/in_out_result.h>
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__memory/concepts.h>
+#include <__memory/uninitialized_algorithms.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/move.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+// uninitialized_default_construct
+
+namespace __uninitialized_default_construct {
+
+struct __fn {
+ template <__nothrow_forward_iterator _ForwardIterator, __nothrow_sentinel_for<_ForwardIterator> _Sentinel>
+ requires default_initializable<iter_value_t<_ForwardIterator>>
+ _LIBCPP_HIDE_FROM_ABI _ForwardIterator operator()(_ForwardIterator __first, _Sentinel __last) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_ForwardIterator>>;
+ return std::__uninitialized_default_construct<_ValueType>(std::move(__first), std::move(__last));
+ }
+
+ template <__nothrow_forward_range _ForwardRange>
+ requires default_initializable<range_value_t<_ForwardRange>>
+ _LIBCPP_HIDE_FROM_ABI borrowed_iterator_t<_ForwardRange> operator()(_ForwardRange&& __range) const {
+ return (*this)(ranges::begin(__range), ranges::end(__range));
+ }
+};
+
+} // namespace __uninitialized_default_construct
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_default_construct = __uninitialized_default_construct::__fn{};
+} // namespace __cpo
+
+// uninitialized_default_construct_n
+
+namespace __uninitialized_default_construct_n {
+
+struct __fn {
+ template <__nothrow_forward_iterator _ForwardIterator>
+ requires default_initializable<iter_value_t<_ForwardIterator>>
+ _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+ operator()(_ForwardIterator __first, iter_difference_t<_ForwardIterator> __n) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_ForwardIterator>>;
+ return std::__uninitialized_default_construct_n<_ValueType>(std::move(__first), __n);
+ }
+};
+
+} // namespace __uninitialized_default_construct_n
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_default_construct_n = __uninitialized_default_construct_n::__fn{};
+} // namespace __cpo
+
+// uninitialized_value_construct
+
+namespace __uninitialized_value_construct {
+
+struct __fn {
+ template <__nothrow_forward_iterator _ForwardIterator, __nothrow_sentinel_for<_ForwardIterator> _Sentinel>
+ requires default_initializable<iter_value_t<_ForwardIterator>>
+ _LIBCPP_HIDE_FROM_ABI _ForwardIterator operator()(_ForwardIterator __first, _Sentinel __last) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_ForwardIterator>>;
+ return std::__uninitialized_value_construct<_ValueType>(std::move(__first), std::move(__last));
+ }
+
+ template <__nothrow_forward_range _ForwardRange>
+ requires default_initializable<range_value_t<_ForwardRange>>
+ _LIBCPP_HIDE_FROM_ABI borrowed_iterator_t<_ForwardRange> operator()(_ForwardRange&& __range) const {
+ return (*this)(ranges::begin(__range), ranges::end(__range));
+ }
+};
+
+} // namespace __uninitialized_value_construct
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_value_construct = __uninitialized_value_construct::__fn{};
+} // namespace __cpo
+
+// uninitialized_value_construct_n
+
+namespace __uninitialized_value_construct_n {
+
+struct __fn {
+ template <__nothrow_forward_iterator _ForwardIterator>
+ requires default_initializable<iter_value_t<_ForwardIterator>>
+ _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+ operator()(_ForwardIterator __first, iter_difference_t<_ForwardIterator> __n) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_ForwardIterator>>;
+ return std::__uninitialized_value_construct_n<_ValueType>(std::move(__first), __n);
+ }
+};
+
+} // namespace __uninitialized_value_construct_n
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_value_construct_n = __uninitialized_value_construct_n::__fn{};
+} // namespace __cpo
+
+// uninitialized_fill
+
+namespace __uninitialized_fill {
+
+struct __fn {
+ template <__nothrow_forward_iterator _ForwardIterator, __nothrow_sentinel_for<_ForwardIterator> _Sentinel, class _Tp>
+ requires constructible_from<iter_value_t<_ForwardIterator>, const _Tp&>
+ _LIBCPP_HIDE_FROM_ABI _ForwardIterator operator()(_ForwardIterator __first, _Sentinel __last, const _Tp& __x) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_ForwardIterator>>;
+ return std::__uninitialized_fill<_ValueType>(std::move(__first), std::move(__last), __x);
+ }
+
+ template <__nothrow_forward_range _ForwardRange, class _Tp>
+ requires constructible_from<range_value_t<_ForwardRange>, const _Tp&>
+ _LIBCPP_HIDE_FROM_ABI borrowed_iterator_t<_ForwardRange> operator()(_ForwardRange&& __range, const _Tp& __x) const {
+ return (*this)(ranges::begin(__range), ranges::end(__range), __x);
+ }
+};
+
+} // namespace __uninitialized_fill
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_fill = __uninitialized_fill::__fn{};
+} // namespace __cpo
+
+// uninitialized_fill_n
+
+namespace __uninitialized_fill_n {
+
+struct __fn {
+ template <__nothrow_forward_iterator _ForwardIterator, class _Tp>
+ requires constructible_from<iter_value_t<_ForwardIterator>, const _Tp&>
+ _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+ operator()(_ForwardIterator __first, iter_difference_t<_ForwardIterator> __n, const _Tp& __x) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_ForwardIterator>>;
+ return std::__uninitialized_fill_n<_ValueType>(std::move(__first), __n, __x);
+ }
+};
+
+} // namespace __uninitialized_fill_n
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_fill_n = __uninitialized_fill_n::__fn{};
+} // namespace __cpo
+
+// uninitialized_copy
+
+template <class _InputIterator, class _OutputIterator>
+using uninitialized_copy_result = in_out_result<_InputIterator, _OutputIterator>;
+
+namespace __uninitialized_copy {
+
+struct __fn {
+ template <input_iterator _InputIterator,
+ sentinel_for<_InputIterator> _Sentinel1,
+ __nothrow_forward_iterator _OutputIterator,
+ __nothrow_sentinel_for<_OutputIterator> _Sentinel2>
+ requires constructible_from<iter_value_t<_OutputIterator>, iter_reference_t<_InputIterator>>
+ _LIBCPP_HIDE_FROM_ABI uninitialized_copy_result<_InputIterator, _OutputIterator>
+ operator()(_InputIterator __ifirst, _Sentinel1 __ilast, _OutputIterator __ofirst, _Sentinel2 __olast) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_OutputIterator>>;
+
+ auto __stop_copying = [&__olast](auto&& __out_iter) -> bool { return __out_iter == __olast; };
+ auto __result = std::__uninitialized_copy<_ValueType>(
+ std::move(__ifirst), std::move(__ilast), std::move(__ofirst), __stop_copying);
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+
+ template <input_range _InputRange, __nothrow_forward_range _OutputRange>
+ requires constructible_from<range_value_t<_OutputRange>, range_reference_t<_InputRange>>
+ _LIBCPP_HIDE_FROM_ABI uninitialized_copy_result<borrowed_iterator_t<_InputRange>, borrowed_iterator_t<_OutputRange>>
+ operator()(_InputRange&& __in_range, _OutputRange&& __out_range) const {
+ return (*this)(
+ ranges::begin(__in_range), ranges::end(__in_range), ranges::begin(__out_range), ranges::end(__out_range));
+ }
+};
+
+} // namespace __uninitialized_copy
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_copy = __uninitialized_copy::__fn{};
+} // namespace __cpo
+
+// uninitialized_copy_n
+
+template <class _InputIterator, class _OutputIterator>
+using uninitialized_copy_n_result = in_out_result<_InputIterator, _OutputIterator>;
+
+namespace __uninitialized_copy_n {
+
+struct __fn {
+ template <input_iterator _InputIterator,
+ __nothrow_forward_iterator _OutputIterator,
+ __nothrow_sentinel_for<_OutputIterator> _Sentinel>
+ requires constructible_from<iter_value_t<_OutputIterator>, iter_reference_t<_InputIterator>>
+ _LIBCPP_HIDE_FROM_ABI uninitialized_copy_n_result<_InputIterator, _OutputIterator>
+ operator()(_InputIterator __ifirst,
+ iter_difference_t<_InputIterator> __n,
+ _OutputIterator __ofirst,
+ _Sentinel __olast) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_OutputIterator>>;
+ auto __stop_copying = [&__olast](auto&& __out_iter) -> bool { return __out_iter == __olast; };
+ auto __result =
+ std::__uninitialized_copy_n<_ValueType>(std::move(__ifirst), __n, std::move(__ofirst), __stop_copying);
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+};
+
+} // namespace __uninitialized_copy_n
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_copy_n = __uninitialized_copy_n::__fn{};
+} // namespace __cpo
+
+// uninitialized_move
+
+template <class _InputIterator, class _OutputIterator>
+using uninitialized_move_result = in_out_result<_InputIterator, _OutputIterator>;
+
+namespace __uninitialized_move {
+
+struct __fn {
+ template <input_iterator _InputIterator,
+ sentinel_for<_InputIterator> _Sentinel1,
+ __nothrow_forward_iterator _OutputIterator,
+ __nothrow_sentinel_for<_OutputIterator> _Sentinel2>
+ requires constructible_from<iter_value_t<_OutputIterator>, iter_rvalue_reference_t<_InputIterator>>
+ _LIBCPP_HIDE_FROM_ABI uninitialized_move_result<_InputIterator, _OutputIterator>
+ operator()(_InputIterator __ifirst, _Sentinel1 __ilast, _OutputIterator __ofirst, _Sentinel2 __olast) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_OutputIterator>>;
+ auto __iter_move = [](auto&& __iter) -> decltype(auto) { return ranges::iter_move(__iter); };
+ auto __stop_moving = [&__olast](auto&& __out_iter) -> bool { return __out_iter == __olast; };
+ auto __result = std::__uninitialized_move<_ValueType>(
+ std::move(__ifirst), std::move(__ilast), std::move(__ofirst), __stop_moving, __iter_move);
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+
+ template <input_range _InputRange, __nothrow_forward_range _OutputRange>
+ requires constructible_from<range_value_t<_OutputRange>, range_rvalue_reference_t<_InputRange>>
+ _LIBCPP_HIDE_FROM_ABI uninitialized_move_result<borrowed_iterator_t<_InputRange>, borrowed_iterator_t<_OutputRange>>
+ operator()(_InputRange&& __in_range, _OutputRange&& __out_range) const {
+ return (*this)(
+ ranges::begin(__in_range), ranges::end(__in_range), ranges::begin(__out_range), ranges::end(__out_range));
+ }
+};
+
+} // namespace __uninitialized_move
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_move = __uninitialized_move::__fn{};
+} // namespace __cpo
+
+// uninitialized_move_n
+
+template <class _InputIterator, class _OutputIterator>
+using uninitialized_move_n_result = in_out_result<_InputIterator, _OutputIterator>;
+
+namespace __uninitialized_move_n {
+
+struct __fn {
+ template <input_iterator _InputIterator,
+ __nothrow_forward_iterator _OutputIterator,
+ __nothrow_sentinel_for<_OutputIterator> _Sentinel>
+ requires constructible_from<iter_value_t<_OutputIterator>, iter_rvalue_reference_t<_InputIterator>>
+ _LIBCPP_HIDE_FROM_ABI uninitialized_move_n_result<_InputIterator, _OutputIterator>
+ operator()(_InputIterator __ifirst,
+ iter_difference_t<_InputIterator> __n,
+ _OutputIterator __ofirst,
+ _Sentinel __olast) const {
+ using _ValueType = remove_reference_t<iter_reference_t<_OutputIterator>>;
+ auto __iter_move = [](auto&& __iter) -> decltype(auto) { return ranges::iter_move(__iter); };
+ auto __stop_moving = [&__olast](auto&& __out_iter) -> bool { return __out_iter == __olast; };
+ auto __result = std::__uninitialized_move_n<_ValueType>(
+ std::move(__ifirst), __n, std::move(__ofirst), __stop_moving, __iter_move);
+ return {std::move(__result.first), std::move(__result.second)};
+ }
+};
+
+} // namespace __uninitialized_move_n
+
+inline namespace __cpo {
+inline constexpr auto uninitialized_move_n = __uninitialized_move_n::__fn{};
+} // namespace __cpo
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_RANGES_UNINITIALIZED_ALGORITHMS_H
diff --git a/libcxx/include/__cxx03/__memory/raw_storage_iterator.h b/libcxx/include/__cxx03/__memory/raw_storage_iterator.h
new file mode 100644
index 00000000000000..774878aa1c5e81
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/raw_storage_iterator.h
@@ -0,0 +1,87 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RAW_STORAGE_ITERATOR_H
+#define _LIBCPP___MEMORY_RAW_STORAGE_ITERATOR_H
+
+#include <__config>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_RAW_STORAGE_ITERATOR)
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _OutputIterator, class _Tp>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 raw_storage_iterator
+# if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
+ : public iterator<output_iterator_tag, void, void, void, void>
+# endif
+{
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+private:
+ _OutputIterator __x_;
+
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+# if _LIBCPP_STD_VER >= 20
+ typedef ptrdiff_t difference_type;
+# else
+ typedef void difference_type;
+# endif
+ typedef void pointer;
+ typedef void reference;
+
+ _LIBCPP_HIDE_FROM_ABI explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
+ _LIBCPP_HIDE_FROM_ABI raw_storage_iterator& operator*() { return *this; }
+ _LIBCPP_HIDE_FROM_ABI raw_storage_iterator& operator=(const _Tp& __element) {
+ ::new ((void*)std::addressof(*__x_)) _Tp(__element);
+ return *this;
+ }
+# if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI raw_storage_iterator& operator=(_Tp&& __element) {
+ ::new ((void*)std::addressof(*__x_)) _Tp(std::move(__element));
+ return *this;
+ }
+# endif
+ _LIBCPP_HIDE_FROM_ABI raw_storage_iterator& operator++() {
+ ++__x_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI raw_storage_iterator operator++(int) {
+ raw_storage_iterator __t(*this);
+ ++__x_;
+ return __t;
+ }
+# if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI _OutputIterator base() const { return __x_; }
+# endif
+};
+
+#endif // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_RAW_STORAGE_ITERATOR)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_RAW_STORAGE_ITERATOR_H
diff --git a/libcxx/include/__cxx03/__memory/shared_ptr.h b/libcxx/include/__cxx03/__memory/shared_ptr.h
new file mode 100644
index 00000000000000..d487e4fbe3a953
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/shared_ptr.h
@@ -0,0 +1,1694 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_SHARED_PTR_H
+#define _LIBCPP___MEMORY_SHARED_PTR_H
+
+#include <__compare/compare_three_way.h>
+#include <__compare/ordering.h>
+#include <__config>
+#include <__exception/exception.h>
+#include <__functional/binary_function.h>
+#include <__functional/operations.h>
+#include <__functional/reference_wrapper.h>
+#include <__fwd/ostream.h>
+#include <__iterator/access.h>
+#include <__memory/addressof.h>
+#include <__memory/allocation_guard.h>
+#include <__memory/allocator.h>
+#include <__memory/allocator_destructor.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/auto_ptr.h>
+#include <__memory/compressed_pair.h>
+#include <__memory/construct_at.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/uninitialized_algorithms.h>
+#include <__memory/unique_ptr.h>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/disjunction.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_bounded_array.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_unbounded_array.h>
+#include <__type_traits/nat.h>
+#include <__type_traits/negation.h>
+#include <__type_traits/remove_extent.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <__verbose_abort>
+#include <cstddef>
+#include <new>
+#include <typeinfo>
+#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
+# include <__atomic/memory_order.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// NOTE: Relaxed and acq/rel atomics (for increment and decrement respectively)
+// should be sufficient for thread safety.
+// See https://llvm.org/PR22803
+#if defined(__clang__) && __has_builtin(__atomic_add_fetch) && defined(__ATOMIC_RELAXED) && defined(__ATOMIC_ACQ_REL)
+# define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
+#elif defined(_LIBCPP_COMPILER_GCC)
+# define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
+#endif
+
+template <class _ValueType>
+inline _LIBCPP_HIDE_FROM_ABI _ValueType __libcpp_relaxed_load(_ValueType const* __value) {
+#if !defined(_LIBCPP_HAS_NO_THREADS) && defined(__ATOMIC_RELAXED) && \
+ (__has_builtin(__atomic_load_n) || defined(_LIBCPP_COMPILER_GCC))
+ return __atomic_load_n(__value, __ATOMIC_RELAXED);
+#else
+ return *__value;
+#endif
+}
+
+template <class _ValueType>
+inline _LIBCPP_HIDE_FROM_ABI _ValueType __libcpp_acquire_load(_ValueType const* __value) {
+#if !defined(_LIBCPP_HAS_NO_THREADS) && defined(__ATOMIC_ACQUIRE) && \
+ (__has_builtin(__atomic_load_n) || defined(_LIBCPP_COMPILER_GCC))
+ return __atomic_load_n(__value, __ATOMIC_ACQUIRE);
+#else
+ return *__value;
+#endif
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _Tp __libcpp_atomic_refcount_increment(_Tp& __t) _NOEXCEPT {
+#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
+ return __atomic_add_fetch(&__t, 1, __ATOMIC_RELAXED);
+#else
+ return __t += 1;
+#endif
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _Tp __libcpp_atomic_refcount_decrement(_Tp& __t) _NOEXCEPT {
+#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
+ return __atomic_add_fetch(&__t, -1, __ATOMIC_ACQ_REL);
+#else
+ return __t -= 1;
+#endif
+}
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_weak_ptr : public std::exception {
+public:
+ _LIBCPP_HIDE_FROM_ABI bad_weak_ptr() _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_weak_ptr(const bad_weak_ptr&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_weak_ptr& operator=(const bad_weak_ptr&) _NOEXCEPT = default;
+ ~bad_weak_ptr() _NOEXCEPT override;
+ const char* what() const _NOEXCEPT override;
+};
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_bad_weak_ptr() {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw bad_weak_ptr();
+#else
+ _LIBCPP_VERBOSE_ABORT("bad_weak_ptr was thrown in -fno-exceptions mode");
+#endif
+}
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS weak_ptr;
+
+class _LIBCPP_EXPORTED_FROM_ABI __shared_count {
+ __shared_count(const __shared_count&);
+ __shared_count& operator=(const __shared_count&);
+
+protected:
+ long __shared_owners_;
+ virtual ~__shared_count();
+
+private:
+ virtual void __on_zero_shared() _NOEXCEPT = 0;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __shared_count(long __refs = 0) _NOEXCEPT : __shared_owners_(__refs) {}
+
+#if defined(_LIBCPP_SHARED_PTR_DEFINE_LEGACY_INLINE_FUNCTIONS)
+ void __add_shared() noexcept;
+ bool __release_shared() noexcept;
+#else
+ _LIBCPP_HIDE_FROM_ABI void __add_shared() _NOEXCEPT { __libcpp_atomic_refcount_increment(__shared_owners_); }
+ _LIBCPP_HIDE_FROM_ABI bool __release_shared() _NOEXCEPT {
+ if (__libcpp_atomic_refcount_decrement(__shared_owners_) == -1) {
+ __on_zero_shared();
+ return true;
+ }
+ return false;
+ }
+#endif
+ _LIBCPP_HIDE_FROM_ABI long use_count() const _NOEXCEPT { return __libcpp_relaxed_load(&__shared_owners_) + 1; }
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI __shared_weak_count : private __shared_count {
+ long __shared_weak_owners_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __shared_weak_count(long __refs = 0) _NOEXCEPT
+ : __shared_count(__refs),
+ __shared_weak_owners_(__refs) {}
+
+protected:
+ ~__shared_weak_count() override;
+
+public:
+#if defined(_LIBCPP_SHARED_PTR_DEFINE_LEGACY_INLINE_FUNCTIONS)
+ void __add_shared() noexcept;
+ void __add_weak() noexcept;
+ void __release_shared() noexcept;
+#else
+ _LIBCPP_HIDE_FROM_ABI void __add_shared() _NOEXCEPT { __shared_count::__add_shared(); }
+ _LIBCPP_HIDE_FROM_ABI void __add_weak() _NOEXCEPT { __libcpp_atomic_refcount_increment(__shared_weak_owners_); }
+ _LIBCPP_HIDE_FROM_ABI void __release_shared() _NOEXCEPT {
+ if (__shared_count::__release_shared())
+ __release_weak();
+ }
+#endif
+ void __release_weak() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI long use_count() const _NOEXCEPT { return __shared_count::use_count(); }
+ __shared_weak_count* lock() _NOEXCEPT;
+
+ virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
+
+private:
+ virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
+};
+
+template <class _Tp, class _Dp, class _Alloc>
+class __shared_ptr_pointer : public __shared_weak_count {
+ __compressed_pair<__compressed_pair<_Tp, _Dp>, _Alloc> __data_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
+ : __data_(__compressed_pair<_Tp, _Dp>(__p, std::move(__d)), std::move(__a)) {}
+
+#ifndef _LIBCPP_HAS_NO_RTTI
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const void* __get_deleter(const type_info&) const _NOEXCEPT override;
+#endif
+
+private:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared() _NOEXCEPT override;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared_weak() _NOEXCEPT override;
+};
+
+#ifndef _LIBCPP_HAS_NO_RTTI
+
+template <class _Tp, class _Dp, class _Alloc>
+const void* __shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) const _NOEXCEPT {
+ return __t == typeid(_Dp) ? std::addressof(__data_.first().second()) : nullptr;
+}
+
+#endif // _LIBCPP_HAS_NO_RTTI
+
+template <class _Tp, class _Dp, class _Alloc>
+void __shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared() _NOEXCEPT {
+ __data_.first().second()(__data_.first().first());
+ __data_.first().second().~_Dp();
+}
+
+template <class _Tp, class _Dp, class _Alloc>
+void __shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT {
+ typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_pointer>::type _Al;
+ typedef allocator_traits<_Al> _ATraits;
+ typedef pointer_traits<typename _ATraits::pointer> _PTraits;
+
+ _Al __a(__data_.second());
+ __data_.second().~_Alloc();
+ __a.deallocate(_PTraits::pointer_to(*this), 1);
+}
+
+// This tag is used to instantiate an allocator type. The various shared_ptr control blocks
+// detect that the allocator has been instantiated for this type and perform alternative
+// initialization/destruction based on that.
+struct __for_overwrite_tag {};
+
+template <class _Tp, class _Alloc>
+struct __shared_ptr_emplace : __shared_weak_count {
+ template <class... _Args,
+ class _Allocator = _Alloc,
+ __enable_if_t<is_same<typename _Allocator::value_type, __for_overwrite_tag>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit __shared_ptr_emplace(_Alloc __a, _Args&&...) : __storage_(std::move(__a)) {
+ static_assert(
+ sizeof...(_Args) == 0, "No argument should be provided to the control block when using _for_overwrite");
+ ::new ((void*)__get_elem()) _Tp;
+ }
+
+ template <class... _Args,
+ class _Allocator = _Alloc,
+ __enable_if_t<!is_same<typename _Allocator::value_type, __for_overwrite_tag>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit __shared_ptr_emplace(_Alloc __a, _Args&&... __args) : __storage_(std::move(__a)) {
+ using _TpAlloc = typename __allocator_traits_rebind<_Alloc, __remove_cv_t<_Tp> >::type;
+ _TpAlloc __tmp(*__get_alloc());
+ allocator_traits<_TpAlloc>::construct(__tmp, __get_elem(), std::forward<_Args>(__args)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Alloc* __get_alloc() _NOEXCEPT { return __storage_.__get_alloc(); }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* __get_elem() _NOEXCEPT { return __storage_.__get_elem(); }
+
+private:
+ template <class _Allocator = _Alloc,
+ __enable_if_t<is_same<typename _Allocator::value_type, __for_overwrite_tag>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void __on_zero_shared_impl() _NOEXCEPT {
+ __get_elem()->~_Tp();
+ }
+
+ template <class _Allocator = _Alloc,
+ __enable_if_t<!is_same<typename _Allocator::value_type, __for_overwrite_tag>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void __on_zero_shared_impl() _NOEXCEPT {
+ using _TpAlloc = typename __allocator_traits_rebind<_Allocator, __remove_cv_t<_Tp> >::type;
+ _TpAlloc __tmp(*__get_alloc());
+ allocator_traits<_TpAlloc>::destroy(__tmp, __get_elem());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared() _NOEXCEPT override { __on_zero_shared_impl(); }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared_weak() _NOEXCEPT override {
+ using _ControlBlockAlloc = typename __allocator_traits_rebind<_Alloc, __shared_ptr_emplace>::type;
+ using _ControlBlockPointer = typename allocator_traits<_ControlBlockAlloc>::pointer;
+ _ControlBlockAlloc __tmp(*__get_alloc());
+ __storage_.~_Storage();
+ allocator_traits<_ControlBlockAlloc>::deallocate(__tmp, pointer_traits<_ControlBlockPointer>::pointer_to(*this), 1);
+ }
+
+ // This class implements the control block for non-array shared pointers created
+ // through `std::allocate_shared` and `std::make_shared`.
+ //
+ // In previous versions of the library, we used a compressed pair to store
+ // both the _Alloc and the _Tp. This implies using EBO, which is incompatible
+ // with Allocator construction for _Tp. To allow implementing P0674 in C++20,
+ // we now use a properly aligned char buffer while making sure that we maintain
+ // the same layout that we had when we used a compressed pair.
+ using _CompressedPair = __compressed_pair<_Alloc, _Tp>;
+ struct _ALIGNAS_TYPE(_CompressedPair) _Storage {
+ char __blob_[sizeof(_CompressedPair)];
+
+ _LIBCPP_HIDE_FROM_ABI explicit _Storage(_Alloc&& __a) { ::new ((void*)__get_alloc()) _Alloc(std::move(__a)); }
+ _LIBCPP_HIDE_FROM_ABI ~_Storage() { __get_alloc()->~_Alloc(); }
+ _LIBCPP_HIDE_FROM_ABI _Alloc* __get_alloc() _NOEXCEPT {
+ _CompressedPair* __as_pair = reinterpret_cast<_CompressedPair*>(__blob_);
+ typename _CompressedPair::_Base1* __first = _CompressedPair::__get_first_base(__as_pair);
+ _Alloc* __alloc = reinterpret_cast<_Alloc*>(__first);
+ return __alloc;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_CFI _Tp* __get_elem() _NOEXCEPT {
+ _CompressedPair* __as_pair = reinterpret_cast<_CompressedPair*>(__blob_);
+ typename _CompressedPair::_Base2* __second = _CompressedPair::__get_second_base(__as_pair);
+ _Tp* __elem = reinterpret_cast<_Tp*>(__second);
+ return __elem;
+ }
+ };
+
+ static_assert(_LIBCPP_ALIGNOF(_Storage) == _LIBCPP_ALIGNOF(_CompressedPair), "");
+ static_assert(sizeof(_Storage) == sizeof(_CompressedPair), "");
+ _Storage __storage_;
+};
+
+struct __shared_ptr_dummy_rebind_allocator_type;
+template <>
+class _LIBCPP_TEMPLATE_VIS allocator<__shared_ptr_dummy_rebind_allocator_type> {
+public:
+ template <class _Other>
+ struct rebind {
+ typedef allocator<_Other> other;
+ };
+};
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS enable_shared_from_this;
+
+// http://eel.is/c++draft/util.sharedptr#util.smartptr.shared.general-6
+// A pointer type Y* is said to be compatible with a pointer type T*
+// when either Y* is convertible to T* or Y is U[N] and T is cv U[].
+#if _LIBCPP_STD_VER >= 17
+template <class _Yp, class _Tp>
+struct __bounded_convertible_to_unbounded : false_type {};
+
+template <class _Up, std::size_t _Np, class _Tp>
+struct __bounded_convertible_to_unbounded<_Up[_Np], _Tp> : is_same<__remove_cv_t<_Tp>, _Up[]> {};
+
+template <class _Yp, class _Tp>
+struct __compatible_with : _Or< is_convertible<_Yp*, _Tp*>, __bounded_convertible_to_unbounded<_Yp, _Tp> > {};
+#else
+template <class _Yp, class _Tp>
+struct __compatible_with : is_convertible<_Yp*, _Tp*> {};
+#endif // _LIBCPP_STD_VER >= 17
+
+// Constructors that take raw pointers have a different set of "compatible" constraints
+// http://eel.is/c++draft/util.sharedptr#util.smartptr.shared.const-9.1
+// - If T is an array type, then either T is U[N] and Y(*)[N] is convertible to T*,
+// or T is U[] and Y(*)[] is convertible to T*.
+// - If T is not an array type, then Y* is convertible to T*.
+#if _LIBCPP_STD_VER >= 17
+template <class _Yp, class _Tp, class = void>
+struct __raw_pointer_compatible_with : _And< _Not<is_array<_Tp>>, is_convertible<_Yp*, _Tp*> > {};
+
+template <class _Yp, class _Up, std::size_t _Np>
+struct __raw_pointer_compatible_with<_Yp, _Up[_Np], __enable_if_t< is_convertible<_Yp (*)[_Np], _Up (*)[_Np]>::value> >
+ : true_type {};
+
+template <class _Yp, class _Up>
+struct __raw_pointer_compatible_with<_Yp, _Up[], __enable_if_t< is_convertible<_Yp (*)[], _Up (*)[]>::value> >
+ : true_type {};
+
+#else
+template <class _Yp, class _Tp>
+struct __raw_pointer_compatible_with : is_convertible<_Yp*, _Tp*> {};
+#endif // _LIBCPP_STD_VER >= 17
+
+template <class _Ptr, class = void>
+struct __is_deletable : false_type {};
+template <class _Ptr>
+struct __is_deletable<_Ptr, decltype(delete std::declval<_Ptr>())> : true_type {};
+
+template <class _Ptr, class = void>
+struct __is_array_deletable : false_type {};
+template <class _Ptr>
+struct __is_array_deletable<_Ptr, decltype(delete[] std::declval<_Ptr>())> : true_type {};
+
+template <class _Dp, class _Pt, class = decltype(std::declval<_Dp>()(std::declval<_Pt>()))>
+true_type __well_formed_deleter_test(int);
+
+template <class, class>
+false_type __well_formed_deleter_test(...);
+
+template <class _Dp, class _Pt>
+struct __well_formed_deleter : decltype(std::__well_formed_deleter_test<_Dp, _Pt>(0)) {};
+
+template <class _Dp, class _Yp, class _Tp>
+struct __shared_ptr_deleter_ctor_reqs {
+ static const bool value = __raw_pointer_compatible_with<_Yp, _Tp>::value && is_move_constructible<_Dp>::value &&
+ __well_formed_deleter<_Dp, _Yp*>::value;
+};
+
+template <class _Dp>
+using __shared_ptr_nullptr_deleter_ctor_reqs = _And<is_move_constructible<_Dp>, __well_formed_deleter<_Dp, nullptr_t> >;
+
+#if defined(_LIBCPP_ABI_ENABLE_SHARED_PTR_TRIVIAL_ABI)
+# define _LIBCPP_SHARED_PTR_TRIVIAL_ABI __attribute__((__trivial_abi__))
+#else
+# define _LIBCPP_SHARED_PTR_TRIVIAL_ABI
+#endif
+
+template <class _Tp>
+class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS shared_ptr {
+ struct __nullptr_sfinae_tag {};
+
+public:
+#if _LIBCPP_STD_VER >= 17
+ typedef weak_ptr<_Tp> weak_type;
+ typedef remove_extent_t<_Tp> element_type;
+#else
+ typedef _Tp element_type;
+#endif
+
+ // A shared_ptr contains only two raw pointers which point to the heap and move constructing already doesn't require
+ // any bookkeeping, so it's always trivially relocatable.
+ using __trivially_relocatable = shared_ptr;
+
+private:
+ element_type* __ptr_;
+ __shared_weak_count* __cntrl_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR shared_ptr() _NOEXCEPT : __ptr_(nullptr), __cntrl_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR shared_ptr(nullptr_t) _NOEXCEPT : __ptr_(nullptr), __cntrl_(nullptr) {}
+
+ template <class _Yp,
+ __enable_if_t< _And< __raw_pointer_compatible_with<_Yp, _Tp>
+ // In C++03 we get errors when trying to do SFINAE with the
+ // delete operator, so we always pretend that it's deletable.
+ // The same happens on GCC.
+#if !defined(_LIBCPP_CXX03_LANG) && !defined(_LIBCPP_COMPILER_GCC)
+ ,
+ _If<is_array<_Tp>::value, __is_array_deletable<_Yp*>, __is_deletable<_Yp*> >
+#endif
+ >::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit shared_ptr(_Yp* __p) : __ptr_(__p) {
+ unique_ptr<_Yp> __hold(__p);
+ typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
+ typedef __shared_ptr_pointer<_Yp*, __shared_ptr_default_delete<_Tp, _Yp>, _AllocT> _CntrlBlk;
+ __cntrl_ = new _CntrlBlk(__p, __shared_ptr_default_delete<_Tp, _Yp>(), _AllocT());
+ __hold.release();
+ __enable_weak_this(__p, __p);
+ }
+
+ template <class _Yp, class _Dp, __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(_Yp* __p, _Dp __d) : __ptr_(__p) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
+ typedef __shared_ptr_pointer<_Yp*, _Dp, _AllocT> _CntrlBlk;
+#ifndef _LIBCPP_CXX03_LANG
+ __cntrl_ = new _CntrlBlk(__p, std::move(__d), _AllocT());
+#else
+ __cntrl_ = new _CntrlBlk(__p, __d, _AllocT());
+#endif // not _LIBCPP_CXX03_LANG
+ __enable_weak_this(__p, __p);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __d(__p);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+
+ template <class _Yp,
+ class _Dp,
+ class _Alloc,
+ __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(_Yp* __p, _Dp __d, _Alloc __a) : __ptr_(__p) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef __shared_ptr_pointer<_Yp*, _Dp, _Alloc> _CntrlBlk;
+ typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
+ typedef __allocator_destructor<_A2> _D2;
+ _A2 __a2(__a);
+ unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
+ ::new ((void*)std::addressof(*__hold2.get()))
+#ifndef _LIBCPP_CXX03_LANG
+ _CntrlBlk(__p, std::move(__d), __a);
+#else
+ _CntrlBlk(__p, __d, __a);
+#endif // not _LIBCPP_CXX03_LANG
+ __cntrl_ = std::addressof(*__hold2.release());
+ __enable_weak_this(__p, __p);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __d(__p);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+
+ template <class _Dp>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(
+ nullptr_t __p,
+ _Dp __d,
+ __enable_if_t<__shared_ptr_nullptr_deleter_ctor_reqs<_Dp>::value, __nullptr_sfinae_tag> = __nullptr_sfinae_tag())
+ : __ptr_(nullptr) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef typename __shared_ptr_default_allocator<_Tp>::type _AllocT;
+ typedef __shared_ptr_pointer<nullptr_t, _Dp, _AllocT> _CntrlBlk;
+#ifndef _LIBCPP_CXX03_LANG
+ __cntrl_ = new _CntrlBlk(__p, std::move(__d), _AllocT());
+#else
+ __cntrl_ = new _CntrlBlk(__p, __d, _AllocT());
+#endif // not _LIBCPP_CXX03_LANG
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __d(__p);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+
+ template <class _Dp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(
+ nullptr_t __p,
+ _Dp __d,
+ _Alloc __a,
+ __enable_if_t<__shared_ptr_nullptr_deleter_ctor_reqs<_Dp>::value, __nullptr_sfinae_tag> = __nullptr_sfinae_tag())
+ : __ptr_(nullptr) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef __shared_ptr_pointer<nullptr_t, _Dp, _Alloc> _CntrlBlk;
+ typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
+ typedef __allocator_destructor<_A2> _D2;
+ _A2 __a2(__a);
+ unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
+ ::new ((void*)std::addressof(*__hold2.get()))
+#ifndef _LIBCPP_CXX03_LANG
+ _CntrlBlk(__p, std::move(__d), __a);
+#else
+ _CntrlBlk(__p, __d, __a);
+#endif // not _LIBCPP_CXX03_LANG
+ __cntrl_ = std::addressof(*__hold2.release());
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __d(__p);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+
+ template <class _Yp>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(const shared_ptr<_Yp>& __r, element_type* __p) _NOEXCEPT
+ : __ptr_(__p),
+ __cntrl_(__r.__cntrl_) {
+ if (__cntrl_)
+ __cntrl_->__add_shared();
+ }
+
+// LWG-2996
+// We don't backport because it is an evolutionary change.
+#if _LIBCPP_STD_VER >= 20
+ template <class _Yp>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(shared_ptr<_Yp>&& __r, element_type* __p) noexcept
+ : __ptr_(__p), __cntrl_(__r.__cntrl_) {
+ __r.__ptr_ = nullptr;
+ __r.__cntrl_ = nullptr;
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(const shared_ptr& __r) _NOEXCEPT : __ptr_(__r.__ptr_), __cntrl_(__r.__cntrl_) {
+ if (__cntrl_)
+ __cntrl_->__add_shared();
+ }
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(const shared_ptr<_Yp>& __r) _NOEXCEPT : __ptr_(__r.__ptr_), __cntrl_(__r.__cntrl_) {
+ if (__cntrl_)
+ __cntrl_->__add_shared();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(shared_ptr&& __r) _NOEXCEPT : __ptr_(__r.__ptr_), __cntrl_(__r.__cntrl_) {
+ __r.__ptr_ = nullptr;
+ __r.__cntrl_ = nullptr;
+ }
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(shared_ptr<_Yp>&& __r) _NOEXCEPT : __ptr_(__r.__ptr_), __cntrl_(__r.__cntrl_) {
+ __r.__ptr_ = nullptr;
+ __r.__cntrl_ = nullptr;
+ }
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit shared_ptr(const weak_ptr<_Yp>& __r)
+ : __ptr_(__r.__ptr_), __cntrl_(__r.__cntrl_ ? __r.__cntrl_->lock() : __r.__cntrl_) {
+ if (__cntrl_ == nullptr)
+ __throw_bad_weak_ptr();
+ }
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
+ template <class _Yp, __enable_if_t<is_convertible<_Yp*, element_type*>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(auto_ptr<_Yp>&& __r) : __ptr_(__r.get()) {
+ typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<__remove_cv_t<_Yp> > > _CntrlBlk;
+ __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<__remove_cv_t<_Yp> >());
+ __enable_weak_this(__r.get(), __r.get());
+ __r.release();
+ }
+#endif
+
+ template <class _Yp,
+ class _Dp,
+ __enable_if_t<!is_lvalue_reference<_Dp>::value && __compatible_with<_Yp, _Tp>::value &&
+ is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(unique_ptr<_Yp, _Dp>&& __r) : __ptr_(__r.get()) {
+#if _LIBCPP_STD_VER >= 14
+ if (__ptr_ == nullptr)
+ __cntrl_ = nullptr;
+ else
+#endif
+ {
+ typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
+ typedef __shared_ptr_pointer<typename unique_ptr<_Yp, _Dp>::pointer, _Dp, _AllocT> _CntrlBlk;
+ __cntrl_ = new _CntrlBlk(__r.get(), std::move(__r.get_deleter()), _AllocT());
+ __enable_weak_this(__r.get(), __r.get());
+ }
+ __r.release();
+ }
+
+ template <class _Yp,
+ class _Dp,
+ class = void,
+ __enable_if_t<is_lvalue_reference<_Dp>::value && __compatible_with<_Yp, _Tp>::value &&
+ is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr(unique_ptr<_Yp, _Dp>&& __r) : __ptr_(__r.get()) {
+#if _LIBCPP_STD_VER >= 14
+ if (__ptr_ == nullptr)
+ __cntrl_ = nullptr;
+ else
+#endif
+ {
+ typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
+ typedef __shared_ptr_pointer<typename unique_ptr<_Yp, _Dp>::pointer,
+ reference_wrapper<__libcpp_remove_reference_t<_Dp> >,
+ _AllocT>
+ _CntrlBlk;
+ __cntrl_ = new _CntrlBlk(__r.get(), std::ref(__r.get_deleter()), _AllocT());
+ __enable_weak_this(__r.get(), __r.get());
+ }
+ __r.release();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~shared_ptr() {
+ if (__cntrl_)
+ __cntrl_->__release_shared();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>& operator=(const shared_ptr& __r) _NOEXCEPT {
+ shared_ptr(__r).swap(*this);
+ return *this;
+ }
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>& operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT {
+ shared_ptr(__r).swap(*this);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>& operator=(shared_ptr&& __r) _NOEXCEPT {
+ shared_ptr(std::move(__r)).swap(*this);
+ return *this;
+ }
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>& operator=(shared_ptr<_Yp>&& __r) {
+ shared_ptr(std::move(__r)).swap(*this);
+ return *this;
+ }
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
+ template <class _Yp,
+ __enable_if_t<!is_array<_Yp>::value && is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>& operator=(auto_ptr<_Yp>&& __r) {
+ shared_ptr(std::move(__r)).swap(*this);
+ return *this;
+ }
+#endif
+
+ template <class _Yp,
+ class _Dp,
+ __enable_if_t<_And< __compatible_with<_Yp, _Tp>,
+ is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*> >::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>& operator=(unique_ptr<_Yp, _Dp>&& __r) {
+ shared_ptr(std::move(__r)).swap(*this);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(shared_ptr& __r) _NOEXCEPT {
+ std::swap(__ptr_, __r.__ptr_);
+ std::swap(__cntrl_, __r.__cntrl_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void reset() _NOEXCEPT { shared_ptr().swap(*this); }
+
+ template <class _Yp, __enable_if_t<__raw_pointer_compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void reset(_Yp* __p) {
+ shared_ptr(__p).swap(*this);
+ }
+
+ template <class _Yp, class _Dp, __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void reset(_Yp* __p, _Dp __d) {
+ shared_ptr(__p, __d).swap(*this);
+ }
+
+ template <class _Yp,
+ class _Dp,
+ class _Alloc,
+ __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void reset(_Yp* __p, _Dp __d, _Alloc __a) {
+ shared_ptr(__p, __d, __a).swap(*this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI element_type* get() const _NOEXCEPT { return __ptr_; }
+
+ _LIBCPP_HIDE_FROM_ABI __add_lvalue_reference_t<element_type> operator*() const _NOEXCEPT { return *__ptr_; }
+
+ _LIBCPP_HIDE_FROM_ABI element_type* operator->() const _NOEXCEPT {
+ static_assert(!is_array<_Tp>::value, "std::shared_ptr<T>::operator-> is only valid when T is not an array type.");
+ return __ptr_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI long use_count() const _NOEXCEPT { return __cntrl_ ? __cntrl_->use_count() : 0; }
+
+#if _LIBCPP_STD_VER < 20 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_SHARED_PTR_UNIQUE)
+ _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_HIDE_FROM_ABI bool unique() const _NOEXCEPT { return use_count() == 1; }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return get() != nullptr; }
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI bool owner_before(shared_ptr<_Up> const& __p) const _NOEXCEPT {
+ return __cntrl_ < __p.__cntrl_;
+ }
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI bool owner_before(weak_ptr<_Up> const& __p) const _NOEXCEPT {
+ return __cntrl_ < __p.__cntrl_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool __owner_equivalent(const shared_ptr& __p) const { return __cntrl_ == __p.__cntrl_; }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI __add_lvalue_reference_t<element_type> operator[](ptrdiff_t __i) const {
+ static_assert(is_array<_Tp>::value, "std::shared_ptr<T>::operator[] is only valid when T is an array type.");
+ return __ptr_[__i];
+ }
+#endif
+
+#ifndef _LIBCPP_HAS_NO_RTTI
+ template <class _Dp>
+ _LIBCPP_HIDE_FROM_ABI _Dp* __get_deleter() const _NOEXCEPT {
+ return static_cast<_Dp*>(__cntrl_ ? const_cast<void*>(__cntrl_->__get_deleter(typeid(_Dp))) : nullptr);
+ }
+#endif // _LIBCPP_HAS_NO_RTTI
+
+ template <class _Yp, class _CntrlBlk>
+ _LIBCPP_HIDE_FROM_ABI static shared_ptr<_Tp> __create_with_control_block(_Yp* __p, _CntrlBlk* __cntrl) _NOEXCEPT {
+ shared_ptr<_Tp> __r;
+ __r.__ptr_ = __p;
+ __r.__cntrl_ = __cntrl;
+ __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
+ return __r;
+ }
+
+private:
+ template <class _Yp, bool = is_function<_Yp>::value>
+ struct __shared_ptr_default_allocator {
+ typedef allocator<__remove_cv_t<_Yp> > type;
+ };
+
+ template <class _Yp>
+ struct __shared_ptr_default_allocator<_Yp, true> {
+ typedef allocator<__shared_ptr_dummy_rebind_allocator_type> type;
+ };
+
+ template <class _Yp,
+ class _OrigPtr,
+ __enable_if_t<is_convertible<_OrigPtr*, const enable_shared_from_this<_Yp>*>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void __enable_weak_this(const enable_shared_from_this<_Yp>* __e, _OrigPtr* __ptr) _NOEXCEPT {
+ typedef __remove_cv_t<_Yp> _RawYp;
+ if (__e && __e->__weak_this_.expired()) {
+ __e->__weak_this_ = shared_ptr<_RawYp>(*this, const_cast<_RawYp*>(static_cast<const _Yp*>(__ptr)));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __enable_weak_this(...) _NOEXCEPT {}
+
+ template <class, class _Yp>
+ struct __shared_ptr_default_delete : default_delete<_Yp> {};
+
+ template <class _Yp, class _Un, size_t _Sz>
+ struct __shared_ptr_default_delete<_Yp[_Sz], _Un> : default_delete<_Yp[]> {};
+
+ template <class _Yp, class _Un>
+ struct __shared_ptr_default_delete<_Yp[], _Un> : default_delete<_Yp[]> {};
+
+ template <class _Up>
+ friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
+ template <class _Up>
+ friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+shared_ptr(weak_ptr<_Tp>) -> shared_ptr<_Tp>;
+template <class _Tp, class _Dp>
+shared_ptr(unique_ptr<_Tp, _Dp>) -> shared_ptr<_Tp>;
+#endif
+
+//
+// std::allocate_shared and std::make_shared
+//
+template <class _Tp, class _Alloc, class... _Args, __enable_if_t<!is_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> allocate_shared(const _Alloc& __a, _Args&&... __args) {
+ using _ControlBlock = __shared_ptr_emplace<_Tp, _Alloc>;
+ using _ControlBlockAllocator = typename __allocator_traits_rebind<_Alloc, _ControlBlock>::type;
+ __allocation_guard<_ControlBlockAllocator> __guard(__a, 1);
+ ::new ((void*)std::addressof(*__guard.__get())) _ControlBlock(__a, std::forward<_Args>(__args)...);
+ auto __control_block = __guard.__release_ptr();
+ return shared_ptr<_Tp>::__create_with_control_block(
+ (*__control_block).__get_elem(), std::addressof(*__control_block));
+}
+
+template <class _Tp, class... _Args, __enable_if_t<!is_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> make_shared(_Args&&... __args) {
+ return std::allocate_shared<_Tp>(allocator<__remove_cv_t<_Tp> >(), std::forward<_Args>(__args)...);
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp, class _Alloc, __enable_if_t<!is_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a) {
+ using _ForOverwriteAllocator = __allocator_traits_rebind_t<_Alloc, __for_overwrite_tag>;
+ _ForOverwriteAllocator __alloc(__a);
+ return std::allocate_shared<_Tp>(__alloc);
+}
+
+template <class _Tp, __enable_if_t<!is_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> make_shared_for_overwrite() {
+ return std::allocate_shared_for_overwrite<_Tp>(allocator<__remove_cv_t<_Tp>>());
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 17
+
+template <size_t _Alignment>
+struct __sp_aligned_storage {
+ alignas(_Alignment) char __storage[_Alignment];
+};
+
+template <class _Tp, class _Alloc>
+struct __unbounded_array_control_block;
+
+template <class _Tp, class _Alloc>
+struct __unbounded_array_control_block<_Tp[], _Alloc> : __shared_weak_count {
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* __get_data() noexcept { return __data_; }
+
+ _LIBCPP_HIDE_FROM_ABI explicit __unbounded_array_control_block(
+ _Alloc const& __alloc, size_t __count, _Tp const& __arg)
+ : __alloc_(__alloc), __count_(__count) {
+ std::__uninitialized_allocator_fill_n_multidimensional(__alloc_, std::begin(__data_), __count_, __arg);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit __unbounded_array_control_block(_Alloc const& __alloc, size_t __count)
+ : __alloc_(__alloc), __count_(__count) {
+# if _LIBCPP_STD_VER >= 20
+ if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+ // We are purposefully not using an allocator-aware default construction because the spec says so.
+ // There's currently no way of expressing default initialization in an allocator-aware manner anyway.
+ std::uninitialized_default_construct_n(std::begin(__data_), __count_);
+ } else {
+ std::__uninitialized_allocator_value_construct_n_multidimensional(__alloc_, std::begin(__data_), __count_);
+ }
+# else
+ std::__uninitialized_allocator_value_construct_n_multidimensional(__alloc_, std::begin(__data_), __count_);
+# endif
+ }
+
+ // Returns the number of bytes required to store a control block followed by the given number
+ // of elements of _Tp, with the whole storage being aligned to a multiple of _Tp's alignment.
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t __bytes_for(size_t __elements) {
+ // When there's 0 elements, the control block alone is enough since it holds one element.
+ // Otherwise, we allocate one fewer element than requested because the control block already
+ // holds one. Also, we use the bitwise formula below to ensure that we allocate enough bytes
+ // for the whole allocation to be a multiple of _Tp's alignment. That formula is taken from [1].
+ //
+ // [1]: https://en.wikipedia.org/wiki/Data_structure_alignment#Computing_padding
+ size_t __bytes = __elements == 0 ? sizeof(__unbounded_array_control_block)
+ : (__elements - 1) * sizeof(_Tp) + sizeof(__unbounded_array_control_block);
+ constexpr size_t __align = alignof(_Tp);
+ return (__bytes + __align - 1) & ~(__align - 1);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ ~__unbounded_array_control_block() override {
+ } // can't be `= default` because of the sometimes-non-trivial union member __data_
+
+private:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared() _NOEXCEPT override {
+# if _LIBCPP_STD_VER >= 20
+ if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+ std::__reverse_destroy(__data_, __data_ + __count_);
+ } else {
+ __allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
+ std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + __count_);
+ }
+# else
+ __allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
+ std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + __count_);
+# endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared_weak() _NOEXCEPT override {
+ using _AlignedStorage = __sp_aligned_storage<alignof(__unbounded_array_control_block)>;
+ using _StorageAlloc = __allocator_traits_rebind_t<_Alloc, _AlignedStorage>;
+ using _PointerTraits = pointer_traits<typename allocator_traits<_StorageAlloc>::pointer>;
+
+ _StorageAlloc __tmp(__alloc_);
+ __alloc_.~_Alloc();
+ size_t __size = __unbounded_array_control_block::__bytes_for(__count_);
+ _AlignedStorage* __storage = reinterpret_cast<_AlignedStorage*>(this);
+ allocator_traits<_StorageAlloc>::deallocate(
+ __tmp, _PointerTraits::pointer_to(*__storage), __size / sizeof(_AlignedStorage));
+ }
+
+ _LIBCPP_NO_UNIQUE_ADDRESS _Alloc __alloc_;
+ size_t __count_;
+ union {
+ _Tp __data_[1];
+ };
+};
+
+template <class _Array, class _Alloc, class... _Arg>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Array>
+__allocate_shared_unbounded_array(const _Alloc& __a, size_t __n, _Arg&&... __arg) {
+ static_assert(__libcpp_is_unbounded_array<_Array>::value);
+ // We compute the number of bytes necessary to hold the control block and the
+ // array elements. Then, we allocate an array of properly-aligned dummy structs
+ // large enough to hold the control block and array. This allows shifting the
+ // burden of aligning memory properly from us to the allocator.
+ using _ControlBlock = __unbounded_array_control_block<_Array, _Alloc>;
+ using _AlignedStorage = __sp_aligned_storage<alignof(_ControlBlock)>;
+ using _StorageAlloc = __allocator_traits_rebind_t<_Alloc, _AlignedStorage>;
+ __allocation_guard<_StorageAlloc> __guard(__a, _ControlBlock::__bytes_for(__n) / sizeof(_AlignedStorage));
+ _ControlBlock* __control_block = reinterpret_cast<_ControlBlock*>(std::addressof(*__guard.__get()));
+ std::__construct_at(__control_block, __a, __n, std::forward<_Arg>(__arg)...);
+ __guard.__release_ptr();
+ return shared_ptr<_Array>::__create_with_control_block(__control_block->__get_data(), __control_block);
+}
+
+template <class _Tp, class _Alloc>
+struct __bounded_array_control_block;
+
+template <class _Tp, size_t _Count, class _Alloc>
+struct __bounded_array_control_block<_Tp[_Count], _Alloc> : __shared_weak_count {
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* __get_data() noexcept { return __data_; }
+
+ _LIBCPP_HIDE_FROM_ABI explicit __bounded_array_control_block(_Alloc const& __alloc, _Tp const& __arg)
+ : __alloc_(__alloc) {
+ std::__uninitialized_allocator_fill_n_multidimensional(__alloc_, std::addressof(__data_[0]), _Count, __arg);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit __bounded_array_control_block(_Alloc const& __alloc) : __alloc_(__alloc) {
+# if _LIBCPP_STD_VER >= 20
+ if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+ // We are purposefully not using an allocator-aware default construction because the spec says so.
+ // There's currently no way of expressing default initialization in an allocator-aware manner anyway.
+ std::uninitialized_default_construct_n(std::addressof(__data_[0]), _Count);
+ } else {
+ std::__uninitialized_allocator_value_construct_n_multidimensional(__alloc_, std::addressof(__data_[0]), _Count);
+ }
+# else
+ std::__uninitialized_allocator_value_construct_n_multidimensional(__alloc_, std::addressof(__data_[0]), _Count);
+# endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ ~__bounded_array_control_block() override {
+ } // can't be `= default` because of the sometimes-non-trivial union member __data_
+
+private:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared() _NOEXCEPT override {
+# if _LIBCPP_STD_VER >= 20
+ if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+ std::__reverse_destroy(__data_, __data_ + _Count);
+ } else {
+ __allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
+ std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + _Count);
+ }
+# else
+ __allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
+ std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + _Count);
+# endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared_weak() _NOEXCEPT override {
+ using _ControlBlockAlloc = __allocator_traits_rebind_t<_Alloc, __bounded_array_control_block>;
+ using _PointerTraits = pointer_traits<typename allocator_traits<_ControlBlockAlloc>::pointer>;
+
+ _ControlBlockAlloc __tmp(__alloc_);
+ __alloc_.~_Alloc();
+ allocator_traits<_ControlBlockAlloc>::deallocate(__tmp, _PointerTraits::pointer_to(*this), 1);
+ }
+
+ _LIBCPP_NO_UNIQUE_ADDRESS _Alloc __alloc_;
+ union {
+ _Tp __data_[_Count];
+ };
+};
+
+template <class _Array, class _Alloc, class... _Arg>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Array> __allocate_shared_bounded_array(const _Alloc& __a, _Arg&&... __arg) {
+ static_assert(__libcpp_is_bounded_array<_Array>::value);
+ using _ControlBlock = __bounded_array_control_block<_Array, _Alloc>;
+ using _ControlBlockAlloc = __allocator_traits_rebind_t<_Alloc, _ControlBlock>;
+
+ __allocation_guard<_ControlBlockAlloc> __guard(__a, 1);
+ _ControlBlock* __control_block = reinterpret_cast<_ControlBlock*>(std::addressof(*__guard.__get()));
+ std::__construct_at(__control_block, __a, std::forward<_Arg>(__arg)...);
+ __guard.__release_ptr();
+ return shared_ptr<_Array>::__create_with_control_block(__control_block->__get_data(), __control_block);
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#if _LIBCPP_STD_VER >= 20
+
+// bounded array variants
+template <class _Tp, class _Alloc, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> allocate_shared(const _Alloc& __a) {
+ return std::__allocate_shared_bounded_array<_Tp>(__a);
+}
+
+template <class _Tp, class _Alloc, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> allocate_shared(const _Alloc& __a, const remove_extent_t<_Tp>& __u) {
+ return std::__allocate_shared_bounded_array<_Tp>(__a, __u);
+}
+
+template <class _Tp, class _Alloc, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a) {
+ using _ForOverwriteAllocator = __allocator_traits_rebind_t<_Alloc, __for_overwrite_tag>;
+ _ForOverwriteAllocator __alloc(__a);
+ return std::__allocate_shared_bounded_array<_Tp>(__alloc);
+}
+
+template <class _Tp, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> make_shared() {
+ return std::__allocate_shared_bounded_array<_Tp>(allocator<_Tp>());
+}
+
+template <class _Tp, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> make_shared(const remove_extent_t<_Tp>& __u) {
+ return std::__allocate_shared_bounded_array<_Tp>(allocator<_Tp>(), __u);
+}
+
+template <class _Tp, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> make_shared_for_overwrite() {
+ return std::__allocate_shared_bounded_array<_Tp>(allocator<__for_overwrite_tag>());
+}
+
+// unbounded array variants
+template <class _Tp, class _Alloc, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> allocate_shared(const _Alloc& __a, size_t __n) {
+ return std::__allocate_shared_unbounded_array<_Tp>(__a, __n);
+}
+
+template <class _Tp, class _Alloc, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> allocate_shared(const _Alloc& __a, size_t __n, const remove_extent_t<_Tp>& __u) {
+ return std::__allocate_shared_unbounded_array<_Tp>(__a, __n, __u);
+}
+
+template <class _Tp, class _Alloc, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a, size_t __n) {
+ using _ForOverwriteAllocator = __allocator_traits_rebind_t<_Alloc, __for_overwrite_tag>;
+ _ForOverwriteAllocator __alloc(__a);
+ return std::__allocate_shared_unbounded_array<_Tp>(__alloc, __n);
+}
+
+template <class _Tp, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> make_shared(size_t __n) {
+ return std::__allocate_shared_unbounded_array<_Tp>(allocator<_Tp>(), __n);
+}
+
+template <class _Tp, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> make_shared(size_t __n, const remove_extent_t<_Tp>& __u) {
+ return std::__allocate_shared_unbounded_array<_Tp>(allocator<_Tp>(), __n, __u);
+}
+
+template <class _Tp, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> make_shared_for_overwrite(size_t __n) {
+ return std::__allocate_shared_unbounded_array<_Tp>(allocator<__for_overwrite_tag>(), __n);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT {
+ return __x.get() == __y.get();
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT {
+ return !(__x == __y);
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT {
+# if _LIBCPP_STD_VER <= 11
+ typedef typename common_type<_Tp*, _Up*>::type _Vp;
+ return less<_Vp>()(__x.get(), __y.get());
+# else
+ return less<>()(__x.get(), __y.get());
+# endif
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT {
+ return __y < __x;
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT {
+ return !(__y < __x);
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT {
+ return !(__x < __y);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) noexcept {
+ return compare_three_way()(__x.get(), __y.get());
+}
+#endif
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT {
+ return !__x;
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT {
+ return !__x;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT {
+ return static_cast<bool>(__x);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT {
+ return static_cast<bool>(__x);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT {
+ return less<typename shared_ptr<_Tp>::element_type*>()(__x.get(), nullptr);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT {
+ return less<typename shared_ptr<_Tp>::element_type*>()(nullptr, __x.get());
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT {
+ return nullptr < __x;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT {
+ return __x < nullptr;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT {
+ return !(nullptr < __x);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT {
+ return !(__x < nullptr);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT {
+ return !(__x < nullptr);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT {
+ return !(nullptr < __x);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(shared_ptr<_Tp> const& __x, nullptr_t) noexcept {
+ return compare_three_way()(__x.get(), static_cast<typename shared_ptr<_Tp>::element_type*>(nullptr));
+}
+#endif
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI void swap(shared_ptr<_Tp>& __x, shared_ptr<_Tp>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> static_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT {
+ return shared_ptr<_Tp>(__r, static_cast< typename shared_ptr<_Tp>::element_type*>(__r.get()));
+}
+
+// LWG-2996
+// We don't backport because it is an evolutionary change.
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> static_pointer_cast(shared_ptr<_Up>&& __r) noexcept {
+ return shared_ptr<_Tp>(std::move(__r), static_cast<typename shared_ptr<_Tp>::element_type*>(__r.get()));
+}
+#endif
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> dynamic_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT {
+ typedef typename shared_ptr<_Tp>::element_type _ET;
+ _ET* __p = dynamic_cast<_ET*>(__r.get());
+ return __p ? shared_ptr<_Tp>(__r, __p) : shared_ptr<_Tp>();
+}
+
+// LWG-2996
+// We don't backport because it is an evolutionary change.
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> dynamic_pointer_cast(shared_ptr<_Up>&& __r) noexcept {
+ auto* __p = dynamic_cast<typename shared_ptr<_Tp>::element_type*>(__r.get());
+ return __p ? shared_ptr<_Tp>(std::move(__r), __p) : shared_ptr<_Tp>();
+}
+#endif
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> const_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT {
+ typedef typename shared_ptr<_Tp>::element_type _RTp;
+ return shared_ptr<_Tp>(__r, const_cast<_RTp*>(__r.get()));
+}
+
+// LWG-2996
+// We don't backport because it is an evolutionary change.
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> const_pointer_cast(shared_ptr<_Up>&& __r) noexcept {
+ return shared_ptr<_Tp>(std::move(__r), const_cast<typename shared_ptr<_Tp>::element_type*>(__r.get()));
+}
+#endif
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> reinterpret_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT {
+ return shared_ptr<_Tp>(__r, reinterpret_cast< typename shared_ptr<_Tp>::element_type*>(__r.get()));
+}
+
+// LWG-2996
+// We don't backport because it is an evolutionary change.
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> reinterpret_pointer_cast(shared_ptr<_Up>&& __r) noexcept {
+ return shared_ptr<_Tp>(std::move(__r), reinterpret_cast<typename shared_ptr<_Tp>::element_type*>(__r.get()));
+}
+#endif
+
+#ifndef _LIBCPP_HAS_NO_RTTI
+
+template <class _Dp, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _Dp* get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT {
+ return __p.template __get_deleter<_Dp>();
+}
+
+#endif // _LIBCPP_HAS_NO_RTTI
+
+template <class _Tp>
+class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS weak_ptr {
+public:
+#if _LIBCPP_STD_VER >= 17
+ typedef remove_extent_t<_Tp> element_type;
+#else
+ typedef _Tp element_type;
+#endif
+
+ // A weak_ptr contains only two raw pointers which point to the heap and move constructing already doesn't require
+ // any bookkeeping, so it's always trivially relocatable.
+ using __trivially_relocatable = weak_ptr;
+
+private:
+ element_type* __ptr_;
+ __shared_weak_count* __cntrl_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR weak_ptr() _NOEXCEPT;
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI weak_ptr(shared_ptr<_Yp> const& __r) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI weak_ptr(weak_ptr const& __r) _NOEXCEPT;
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI weak_ptr(weak_ptr<_Yp> const& __r) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI weak_ptr(weak_ptr&& __r) _NOEXCEPT;
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI weak_ptr(weak_ptr<_Yp>&& __r) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI ~weak_ptr();
+
+ _LIBCPP_HIDE_FROM_ABI weak_ptr& operator=(weak_ptr const& __r) _NOEXCEPT;
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI weak_ptr& operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI weak_ptr& operator=(weak_ptr&& __r) _NOEXCEPT;
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI weak_ptr& operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT;
+
+ template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI weak_ptr& operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(weak_ptr& __r) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI void reset() _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI long use_count() const _NOEXCEPT { return __cntrl_ ? __cntrl_->use_count() : 0; }
+ _LIBCPP_HIDE_FROM_ABI bool expired() const _NOEXCEPT { return __cntrl_ == nullptr || __cntrl_->use_count() == 0; }
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> lock() const _NOEXCEPT;
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI bool owner_before(const shared_ptr<_Up>& __r) const _NOEXCEPT {
+ return __cntrl_ < __r.__cntrl_;
+ }
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI bool owner_before(const weak_ptr<_Up>& __r) const _NOEXCEPT {
+ return __cntrl_ < __r.__cntrl_;
+ }
+
+ template <class _Up>
+ friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
+ template <class _Up>
+ friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+weak_ptr(shared_ptr<_Tp>) -> weak_ptr<_Tp>;
+#endif
+
+template <class _Tp>
+inline _LIBCPP_CONSTEXPR weak_ptr<_Tp>::weak_ptr() _NOEXCEPT : __ptr_(nullptr), __cntrl_(nullptr) {}
+
+template <class _Tp>
+inline weak_ptr<_Tp>::weak_ptr(weak_ptr const& __r) _NOEXCEPT : __ptr_(__r.__ptr_), __cntrl_(__r.__cntrl_) {
+ if (__cntrl_)
+ __cntrl_->__add_weak();
+}
+
+template <class _Tp>
+template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> >
+inline weak_ptr<_Tp>::weak_ptr(shared_ptr<_Yp> const& __r) _NOEXCEPT : __ptr_(__r.__ptr_), __cntrl_(__r.__cntrl_) {
+ if (__cntrl_)
+ __cntrl_->__add_weak();
+}
+
+template <class _Tp>
+template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> >
+inline weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp> const& __r) _NOEXCEPT : __ptr_(nullptr), __cntrl_(nullptr) {
+ shared_ptr<_Yp> __s = __r.lock();
+ *this = weak_ptr<_Tp>(__s);
+}
+
+template <class _Tp>
+inline weak_ptr<_Tp>::weak_ptr(weak_ptr&& __r) _NOEXCEPT : __ptr_(__r.__ptr_), __cntrl_(__r.__cntrl_) {
+ __r.__ptr_ = nullptr;
+ __r.__cntrl_ = nullptr;
+}
+
+template <class _Tp>
+template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> >
+inline weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp>&& __r) _NOEXCEPT : __ptr_(nullptr), __cntrl_(nullptr) {
+ shared_ptr<_Yp> __s = __r.lock();
+ *this = weak_ptr<_Tp>(__s);
+ __r.reset();
+}
+
+template <class _Tp>
+weak_ptr<_Tp>::~weak_ptr() {
+ if (__cntrl_)
+ __cntrl_->__release_weak();
+}
+
+template <class _Tp>
+inline weak_ptr<_Tp>& weak_ptr<_Tp>::operator=(weak_ptr const& __r) _NOEXCEPT {
+ weak_ptr(__r).swap(*this);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> >
+inline weak_ptr<_Tp>& weak_ptr<_Tp>::operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT {
+ weak_ptr(__r).swap(*this);
+ return *this;
+}
+
+template <class _Tp>
+inline weak_ptr<_Tp>& weak_ptr<_Tp>::operator=(weak_ptr&& __r) _NOEXCEPT {
+ weak_ptr(std::move(__r)).swap(*this);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> >
+inline weak_ptr<_Tp>& weak_ptr<_Tp>::operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT {
+ weak_ptr(std::move(__r)).swap(*this);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Yp, __enable_if_t<__compatible_with<_Yp, _Tp>::value, int> >
+inline weak_ptr<_Tp>& weak_ptr<_Tp>::operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT {
+ weak_ptr(__r).swap(*this);
+ return *this;
+}
+
+template <class _Tp>
+inline void weak_ptr<_Tp>::swap(weak_ptr& __r) _NOEXCEPT {
+ std::swap(__ptr_, __r.__ptr_);
+ std::swap(__cntrl_, __r.__cntrl_);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI void swap(weak_ptr<_Tp>& __x, weak_ptr<_Tp>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+template <class _Tp>
+inline void weak_ptr<_Tp>::reset() _NOEXCEPT {
+ weak_ptr().swap(*this);
+}
+
+template <class _Tp>
+shared_ptr<_Tp> weak_ptr<_Tp>::lock() const _NOEXCEPT {
+ shared_ptr<_Tp> __r;
+ __r.__cntrl_ = __cntrl_ ? __cntrl_->lock() : __cntrl_;
+ if (__r.__cntrl_)
+ __r.__ptr_ = __ptr_;
+ return __r;
+}
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp = void>
+struct owner_less;
+#else
+template <class _Tp>
+struct owner_less;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS owner_less<shared_ptr<_Tp> > : __binary_function<shared_ptr<_Tp>, shared_ptr<_Tp>, bool> {
+ _LIBCPP_HIDE_FROM_ABI bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(shared_ptr<_Tp> const& __x, weak_ptr<_Tp> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS owner_less<weak_ptr<_Tp> > : __binary_function<weak_ptr<_Tp>, weak_ptr<_Tp>, bool> {
+ _LIBCPP_HIDE_FROM_ABI bool operator()(weak_ptr<_Tp> const& __x, weak_ptr<_Tp> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(shared_ptr<_Tp> const& __x, weak_ptr<_Tp> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <>
+struct _LIBCPP_TEMPLATE_VIS owner_less<void> {
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(shared_ptr<_Tp> const& __x, weak_ptr<_Up> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(weak_ptr<_Tp> const& __x, weak_ptr<_Up> const& __y) const _NOEXCEPT {
+ return __x.owner_before(__y);
+ }
+ typedef void is_transparent;
+};
+#endif
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS enable_shared_from_this {
+ mutable weak_ptr<_Tp> __weak_this_;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR enable_shared_from_this() _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI enable_shared_from_this(enable_shared_from_this const&) _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI enable_shared_from_this& operator=(enable_shared_from_this const&) _NOEXCEPT { return *this; }
+ _LIBCPP_HIDE_FROM_ABI ~enable_shared_from_this() {}
+
+public:
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> shared_from_this() { return shared_ptr<_Tp>(__weak_this_); }
+ _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp const> shared_from_this() const { return shared_ptr<const _Tp>(__weak_this_); }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI weak_ptr<_Tp> weak_from_this() _NOEXCEPT { return __weak_this_; }
+
+ _LIBCPP_HIDE_FROM_ABI weak_ptr<const _Tp> weak_from_this() const _NOEXCEPT { return __weak_this_; }
+#endif // _LIBCPP_STD_VER >= 17
+
+ template <class _Up>
+ friend class shared_ptr;
+};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS hash;
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS hash<shared_ptr<_Tp> > {
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef shared_ptr<_Tp> argument_type;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef size_t result_type;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const shared_ptr<_Tp>& __ptr) const _NOEXCEPT {
+ return hash<typename shared_ptr<_Tp>::element_type*>()(__ptr.get());
+ }
+};
+
+template <class _CharT, class _Traits, class _Yp>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p);
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+class _LIBCPP_EXPORTED_FROM_ABI __sp_mut {
+ void* __lx_;
+
+public:
+ void lock() _NOEXCEPT;
+ void unlock() _NOEXCEPT;
+
+private:
+ _LIBCPP_CONSTEXPR __sp_mut(void*) _NOEXCEPT;
+ __sp_mut(const __sp_mut&);
+ __sp_mut& operator=(const __sp_mut&);
+
+ friend _LIBCPP_EXPORTED_FROM_ABI __sp_mut& __get_sp_mut(const void*);
+};
+
+_LIBCPP_EXPORTED_FROM_ABI __sp_mut& __get_sp_mut(const void*);
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_is_lock_free(const shared_ptr<_Tp>*) {
+ return false;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> atomic_load(const shared_ptr<_Tp>* __p) {
+ __sp_mut& __m = std::__get_sp_mut(__p);
+ __m.lock();
+ shared_ptr<_Tp> __q = *__p;
+ __m.unlock();
+ return __q;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order) {
+ return std::atomic_load(__p);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r) {
+ __sp_mut& __m = std::__get_sp_mut(__p);
+ __m.lock();
+ __p->swap(__r);
+ __m.unlock();
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI void atomic_store_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order) {
+ std::atomic_store(__p, __r);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp> atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r) {
+ __sp_mut& __m = std::__get_sp_mut(__p);
+ __m.lock();
+ __p->swap(__r);
+ __m.unlock();
+ return __r;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>
+atomic_exchange_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order) {
+ return std::atomic_exchange(__p, __r);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool
+atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w) {
+ shared_ptr<_Tp> __temp;
+ __sp_mut& __m = std::__get_sp_mut(__p);
+ __m.lock();
+ if (__p->__owner_equivalent(*__v)) {
+ std::swap(__temp, *__p);
+ *__p = __w;
+ __m.unlock();
+ return true;
+ }
+ std::swap(__temp, *__v);
+ *__v = *__p;
+ __m.unlock();
+ return false;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool
+atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w) {
+ return std::atomic_compare_exchange_strong(__p, __v, __w);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_strong_explicit(
+ shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w, memory_order, memory_order) {
+ return std::atomic_compare_exchange_strong(__p, __v, __w);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool atomic_compare_exchange_weak_explicit(
+ shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w, memory_order, memory_order) {
+ return std::atomic_compare_exchange_weak(__p, __v, __w);
+}
+
+#endif // !defined(_LIBCPP_HAS_NO_THREADS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_SHARED_PTR_H
diff --git a/libcxx/include/__cxx03/__memory/swap_allocator.h b/libcxx/include/__cxx03/__memory/swap_allocator.h
new file mode 100644
index 00000000000000..b17e082a43c9f0
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/swap_allocator.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_SWAP_ALLOCATOR_H
+#define _LIBCPP___MEMORY_SWAP_ALLOCATOR_H
+
+#include <__config>
+#include <__memory/allocator_traits.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_swappable.h>
+#include <__utility/swap.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <typename _Alloc>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __swap_allocator(_Alloc& __a1, _Alloc& __a2, true_type)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(__is_nothrow_swappable_v<_Alloc>)
+#endif
+{
+ using std::swap;
+ swap(__a1, __a2);
+}
+
+template <typename _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__swap_allocator(_Alloc&, _Alloc&, false_type) _NOEXCEPT {}
+
+template <typename _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __swap_allocator(_Alloc& __a1, _Alloc& __a2)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(__is_nothrow_swappable_v<_Alloc>)
+#endif
+{
+ std::__swap_allocator(
+ __a1, __a2, integral_constant<bool, allocator_traits<_Alloc>::propagate_on_container_swap::value>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_SWAP_ALLOCATOR_H
diff --git a/libcxx/include/__cxx03/__memory/temp_value.h b/libcxx/include/__cxx03/__memory/temp_value.h
new file mode 100644
index 00000000000000..4a133b3fbcf6c0
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/temp_value.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_TEMP_VALUE_H
+#define _LIBCPP___MEMORY_TEMP_VALUE_H
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory/allocator_traits.h>
+#include <__type_traits/aligned_storage.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Alloc>
+struct __temp_value {
+ typedef allocator_traits<_Alloc> _Traits;
+
+#ifdef _LIBCPP_CXX03_LANG
+ typename aligned_storage<sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)>::type __v;
+#else
+ union {
+ _Tp __v;
+ };
+#endif
+ _Alloc& __a;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp* __addr() {
+#ifdef _LIBCPP_CXX03_LANG
+ return reinterpret_cast<_Tp*>(std::addressof(__v));
+#else
+ return std::addressof(__v);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& get() { return *__addr(); }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_CFI _LIBCPP_CONSTEXPR_SINCE_CXX20 __temp_value(_Alloc& __alloc, _Args&&... __args)
+ : __a(__alloc) {
+ _Traits::construct(__a, __addr(), std::forward<_Args>(__args)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__temp_value() { _Traits::destroy(__a, __addr()); }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_TEMP_VALUE_H
diff --git a/libcxx/include/__cxx03/__memory/temporary_buffer.h b/libcxx/include/__cxx03/__memory/temporary_buffer.h
new file mode 100644
index 00000000000000..88799ca95c1f35
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/temporary_buffer.h
@@ -0,0 +1,75 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_TEMPORARY_BUFFER_H
+#define _LIBCPP___MEMORY_TEMPORARY_BUFFER_H
+
+#include <__config>
+#include <__utility/pair.h>
+#include <cstddef>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_CFI _LIBCPP_DEPRECATED_IN_CXX17 pair<_Tp*, ptrdiff_t>
+get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT {
+ pair<_Tp*, ptrdiff_t> __r(0, 0);
+ const ptrdiff_t __m =
+ (~ptrdiff_t(0) ^ ptrdiff_t(ptrdiff_t(1) << (sizeof(ptrdiff_t) * __CHAR_BIT__ - 1))) / sizeof(_Tp);
+ if (__n > __m)
+ __n = __m;
+ while (__n > 0) {
+#if !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
+ if (__is_overaligned_for_new(_LIBCPP_ALIGNOF(_Tp))) {
+ align_val_t __al = align_val_t(_LIBCPP_ALIGNOF(_Tp));
+ __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), __al, nothrow));
+ } else {
+ __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
+ }
+#else
+ if (__is_overaligned_for_new(_LIBCPP_ALIGNOF(_Tp))) {
+ // Since aligned operator new is unavailable, return an empty
+ // buffer rather than one with invalid alignment.
+ return __r;
+ }
+
+ __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
+#endif
+
+ if (__r.first) {
+ __r.second = __n;
+ break;
+ }
+ __n /= 2;
+ }
+ return __r;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_DEPRECATED_IN_CXX17 void return_temporary_buffer(_Tp* __p) _NOEXCEPT {
+ std::__libcpp_deallocate_unsized((void*)__p, _LIBCPP_ALIGNOF(_Tp));
+}
+
+struct __return_temporary_buffer {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI void operator()(_Tp* __p) const {
+ std::return_temporary_buffer(__p);
+ }
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_TEMPORARY_BUFFER_H
diff --git a/libcxx/include/__cxx03/__memory/uninitialized_algorithms.h b/libcxx/include/__cxx03/__memory/uninitialized_algorithms.h
new file mode 100644
index 00000000000000..7475ef5cf85def
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/uninitialized_algorithms.h
@@ -0,0 +1,653 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_UNINITIALIZED_ALGORITHMS_H
+#define _LIBCPP___MEMORY_UNINITIALIZED_ALGORITHMS_H
+
+#include <__algorithm/copy.h>
+#include <__algorithm/move.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__algorithm/unwrap_range.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/construct_at.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/voidify.h>
+#include <__type_traits/extent.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_trivially_assignable.h>
+#include <__type_traits/is_trivially_constructible.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/is_unbounded_array.h>
+#include <__type_traits/negation.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_extent.h>
+#include <__utility/exception_guard.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __always_false {
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool operator()(_Args&&...) const _NOEXCEPT {
+ return false;
+ }
+};
+
+// uninitialized_copy
+
+template <class _ValueType, class _InputIterator, class _Sentinel1, class _ForwardIterator, class _EndPredicate>
+inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator> __uninitialized_copy(
+ _InputIterator __ifirst, _Sentinel1 __ilast, _ForwardIterator __ofirst, _EndPredicate __stop_copying) {
+ _ForwardIterator __idx = __ofirst;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ for (; __ifirst != __ilast && !__stop_copying(__idx); ++__ifirst, (void)++__idx)
+ ::new (std::__voidify(*__idx)) _ValueType(*__ifirst);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__ofirst, __idx);
+ throw;
+ }
+#endif
+
+ return pair<_InputIterator, _ForwardIterator>(std::move(__ifirst), std::move(__idx));
+}
+
+template <class _InputIterator, class _ForwardIterator>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator
+uninitialized_copy(_InputIterator __ifirst, _InputIterator __ilast, _ForwardIterator __ofirst) {
+ typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType;
+ auto __result = std::__uninitialized_copy<_ValueType>(
+ std::move(__ifirst), std::move(__ilast), std::move(__ofirst), __always_false());
+ return std::move(__result.second);
+}
+
+// uninitialized_copy_n
+
+template <class _ValueType, class _InputIterator, class _Size, class _ForwardIterator, class _EndPredicate>
+inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator>
+__uninitialized_copy_n(_InputIterator __ifirst, _Size __n, _ForwardIterator __ofirst, _EndPredicate __stop_copying) {
+ _ForwardIterator __idx = __ofirst;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ for (; __n > 0 && !__stop_copying(__idx); ++__ifirst, (void)++__idx, (void)--__n)
+ ::new (std::__voidify(*__idx)) _ValueType(*__ifirst);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__ofirst, __idx);
+ throw;
+ }
+#endif
+
+ return pair<_InputIterator, _ForwardIterator>(std::move(__ifirst), std::move(__idx));
+}
+
+template <class _InputIterator, class _Size, class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+uninitialized_copy_n(_InputIterator __ifirst, _Size __n, _ForwardIterator __ofirst) {
+ typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType;
+ auto __result =
+ std::__uninitialized_copy_n<_ValueType>(std::move(__ifirst), __n, std::move(__ofirst), __always_false());
+ return std::move(__result.second);
+}
+
+// uninitialized_fill
+
+template <class _ValueType, class _ForwardIterator, class _Sentinel, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+__uninitialized_fill(_ForwardIterator __first, _Sentinel __last, const _Tp& __x) {
+ _ForwardIterator __idx = __first;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ for (; __idx != __last; ++__idx)
+ ::new (std::__voidify(*__idx)) _ValueType(__x);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__first, __idx);
+ throw;
+ }
+#endif
+
+ return __idx;
+}
+
+template <class _ForwardIterator, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI void
+uninitialized_fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __x) {
+ typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType;
+ (void)std::__uninitialized_fill<_ValueType>(__first, __last, __x);
+}
+
+// uninitialized_fill_n
+
+template <class _ValueType, class _ForwardIterator, class _Size, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+__uninitialized_fill_n(_ForwardIterator __first, _Size __n, const _Tp& __x) {
+ _ForwardIterator __idx = __first;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ for (; __n > 0; ++__idx, (void)--__n)
+ ::new (std::__voidify(*__idx)) _ValueType(__x);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__first, __idx);
+ throw;
+ }
+#endif
+
+ return __idx;
+}
+
+template <class _ForwardIterator, class _Size, class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+uninitialized_fill_n(_ForwardIterator __first, _Size __n, const _Tp& __x) {
+ typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType;
+ return std::__uninitialized_fill_n<_ValueType>(__first, __n, __x);
+}
+
+#if _LIBCPP_STD_VER >= 17
+
+// uninitialized_default_construct
+
+template <class _ValueType, class _ForwardIterator, class _Sentinel>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+__uninitialized_default_construct(_ForwardIterator __first, _Sentinel __last) {
+ auto __idx = __first;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+ for (; __idx != __last; ++__idx)
+ ::new (std::__voidify(*__idx)) _ValueType;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__first, __idx);
+ throw;
+ }
+# endif
+
+ return __idx;
+}
+
+template <class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI void uninitialized_default_construct(_ForwardIterator __first, _ForwardIterator __last) {
+ using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
+ (void)std::__uninitialized_default_construct<_ValueType>(std::move(__first), std::move(__last));
+}
+
+// uninitialized_default_construct_n
+
+template <class _ValueType, class _ForwardIterator, class _Size>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator __uninitialized_default_construct_n(_ForwardIterator __first, _Size __n) {
+ auto __idx = __first;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+ for (; __n > 0; ++__idx, (void)--__n)
+ ::new (std::__voidify(*__idx)) _ValueType;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__first, __idx);
+ throw;
+ }
+# endif
+
+ return __idx;
+}
+
+template <class _ForwardIterator, class _Size>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator uninitialized_default_construct_n(_ForwardIterator __first, _Size __n) {
+ using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
+ return std::__uninitialized_default_construct_n<_ValueType>(std::move(__first), __n);
+}
+
+// uninitialized_value_construct
+
+template <class _ValueType, class _ForwardIterator, class _Sentinel>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+__uninitialized_value_construct(_ForwardIterator __first, _Sentinel __last) {
+ auto __idx = __first;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+ for (; __idx != __last; ++__idx)
+ ::new (std::__voidify(*__idx)) _ValueType();
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__first, __idx);
+ throw;
+ }
+# endif
+
+ return __idx;
+}
+
+template <class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI void uninitialized_value_construct(_ForwardIterator __first, _ForwardIterator __last) {
+ using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
+ (void)std::__uninitialized_value_construct<_ValueType>(std::move(__first), std::move(__last));
+}
+
+// uninitialized_value_construct_n
+
+template <class _ValueType, class _ForwardIterator, class _Size>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator __uninitialized_value_construct_n(_ForwardIterator __first, _Size __n) {
+ auto __idx = __first;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+ for (; __n > 0; ++__idx, (void)--__n)
+ ::new (std::__voidify(*__idx)) _ValueType();
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__first, __idx);
+ throw;
+ }
+# endif
+
+ return __idx;
+}
+
+template <class _ForwardIterator, class _Size>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator uninitialized_value_construct_n(_ForwardIterator __first, _Size __n) {
+ using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
+ return std::__uninitialized_value_construct_n<_ValueType>(std::move(__first), __n);
+}
+
+// uninitialized_move
+
+template <class _ValueType,
+ class _InputIterator,
+ class _Sentinel1,
+ class _ForwardIterator,
+ class _EndPredicate,
+ class _IterMove>
+inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator> __uninitialized_move(
+ _InputIterator __ifirst,
+ _Sentinel1 __ilast,
+ _ForwardIterator __ofirst,
+ _EndPredicate __stop_moving,
+ _IterMove __iter_move) {
+ auto __idx = __ofirst;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+ for (; __ifirst != __ilast && !__stop_moving(__idx); ++__idx, (void)++__ifirst) {
+ ::new (std::__voidify(*__idx)) _ValueType(__iter_move(__ifirst));
+ }
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__ofirst, __idx);
+ throw;
+ }
+# endif
+
+ return {std::move(__ifirst), std::move(__idx)};
+}
+
+template <class _InputIterator, class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
+uninitialized_move(_InputIterator __ifirst, _InputIterator __ilast, _ForwardIterator __ofirst) {
+ using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
+ auto __iter_move = [](auto&& __iter) -> decltype(auto) { return std::move(*__iter); };
+
+ auto __result = std::__uninitialized_move<_ValueType>(
+ std::move(__ifirst), std::move(__ilast), std::move(__ofirst), __always_false(), __iter_move);
+ return std::move(__result.second);
+}
+
+// uninitialized_move_n
+
+template <class _ValueType,
+ class _InputIterator,
+ class _Size,
+ class _ForwardIterator,
+ class _EndPredicate,
+ class _IterMove>
+inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator> __uninitialized_move_n(
+ _InputIterator __ifirst, _Size __n, _ForwardIterator __ofirst, _EndPredicate __stop_moving, _IterMove __iter_move) {
+ auto __idx = __ofirst;
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+ for (; __n > 0 && !__stop_moving(__idx); ++__idx, (void)++__ifirst, --__n)
+ ::new (std::__voidify(*__idx)) _ValueType(__iter_move(__ifirst));
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ std::__destroy(__ofirst, __idx);
+ throw;
+ }
+# endif
+
+ return {std::move(__ifirst), std::move(__idx)};
+}
+
+template <class _InputIterator, class _Size, class _ForwardIterator>
+inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator>
+uninitialized_move_n(_InputIterator __ifirst, _Size __n, _ForwardIterator __ofirst) {
+ using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
+ auto __iter_move = [](auto&& __iter) -> decltype(auto) { return std::move(*__iter); };
+
+ return std::__uninitialized_move_n<_ValueType>(
+ std::move(__ifirst), __n, std::move(__ofirst), __always_false(), __iter_move);
+}
+
+// TODO: Rewrite this to iterate left to right and use reverse_iterators when calling
+// Destroys every element in the range [first, last) FROM RIGHT TO LEFT using allocator
+// destruction. If elements are themselves C-style arrays, they are recursively destroyed
+// in the same manner.
+//
+// This function assumes that destructors do not throw, and that the allocator is bound to
+// the correct type.
+template <class _Alloc,
+ class _BidirIter,
+ __enable_if_t<__has_bidirectional_iterator_category<_BidirIter>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr void
+__allocator_destroy_multidimensional(_Alloc& __alloc, _BidirIter __first, _BidirIter __last) noexcept {
+ using _ValueType = typename iterator_traits<_BidirIter>::value_type;
+ static_assert(is_same_v<typename allocator_traits<_Alloc>::value_type, _ValueType>,
+ "The allocator should already be rebound to the correct type");
+
+ if (__first == __last)
+ return;
+
+ if constexpr (is_array_v<_ValueType>) {
+ static_assert(!__libcpp_is_unbounded_array<_ValueType>::value,
+ "arrays of unbounded arrays don't exist, but if they did we would mess up here");
+
+ using _Element = remove_extent_t<_ValueType>;
+ __allocator_traits_rebind_t<_Alloc, _Element> __elem_alloc(__alloc);
+ do {
+ --__last;
+ decltype(auto) __array = *__last;
+ std::__allocator_destroy_multidimensional(__elem_alloc, __array, __array + extent_v<_ValueType>);
+ } while (__last != __first);
+ } else {
+ do {
+ --__last;
+ allocator_traits<_Alloc>::destroy(__alloc, std::addressof(*__last));
+ } while (__last != __first);
+ }
+}
+
+// Constructs the object at the given location using the allocator's construct method.
+//
+// If the object being constructed is an array, each element of the array is allocator-constructed,
+// recursively. If an exception is thrown during the construction of an array, the initialized
+// elements are destroyed in reverse order of initialization using allocator destruction.
+//
+// This function assumes that the allocator is bound to the correct type.
+template <class _Alloc, class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr void __allocator_construct_at_multidimensional(_Alloc& __alloc, _Tp* __loc) {
+ static_assert(is_same_v<typename allocator_traits<_Alloc>::value_type, _Tp>,
+ "The allocator should already be rebound to the correct type");
+
+ if constexpr (is_array_v<_Tp>) {
+ using _Element = remove_extent_t<_Tp>;
+ __allocator_traits_rebind_t<_Alloc, _Element> __elem_alloc(__alloc);
+ size_t __i = 0;
+ _Tp& __array = *__loc;
+
+ // If an exception is thrown, destroy what we have constructed so far in reverse order.
+ auto __guard = std::__make_exception_guard([&]() {
+ std::__allocator_destroy_multidimensional(__elem_alloc, __array, __array + __i);
+ });
+
+ for (; __i != extent_v<_Tp>; ++__i) {
+ std::__allocator_construct_at_multidimensional(__elem_alloc, std::addressof(__array[__i]));
+ }
+ __guard.__complete();
+ } else {
+ allocator_traits<_Alloc>::construct(__alloc, __loc);
+ }
+}
+
+// Constructs the object at the given location using the allocator's construct method, passing along
+// the provided argument.
+//
+// If the object being constructed is an array, the argument is also assumed to be an array. Each
+// each element of the array being constructed is allocator-constructed from the corresponding
+// element of the argument array. If an exception is thrown during the construction of an array,
+// the initialized elements are destroyed in reverse order of initialization using allocator
+// destruction.
+//
+// This function assumes that the allocator is bound to the correct type.
+template <class _Alloc, class _Tp, class _Arg>
+_LIBCPP_HIDE_FROM_ABI constexpr void
+__allocator_construct_at_multidimensional(_Alloc& __alloc, _Tp* __loc, _Arg const& __arg) {
+ static_assert(is_same_v<typename allocator_traits<_Alloc>::value_type, _Tp>,
+ "The allocator should already be rebound to the correct type");
+
+ if constexpr (is_array_v<_Tp>) {
+ static_assert(is_array_v<_Arg>,
+ "Provided non-array initialization argument to __allocator_construct_at_multidimensional when "
+ "trying to construct an array.");
+
+ using _Element = remove_extent_t<_Tp>;
+ __allocator_traits_rebind_t<_Alloc, _Element> __elem_alloc(__alloc);
+ size_t __i = 0;
+ _Tp& __array = *__loc;
+
+ // If an exception is thrown, destroy what we have constructed so far in reverse order.
+ auto __guard = std::__make_exception_guard([&]() {
+ std::__allocator_destroy_multidimensional(__elem_alloc, __array, __array + __i);
+ });
+ for (; __i != extent_v<_Tp>; ++__i) {
+ std::__allocator_construct_at_multidimensional(__elem_alloc, std::addressof(__array[__i]), __arg[__i]);
+ }
+ __guard.__complete();
+ } else {
+ allocator_traits<_Alloc>::construct(__alloc, __loc, __arg);
+ }
+}
+
+// Given a range starting at it and containing n elements, initializes each element in the
+// range from left to right using the construct method of the allocator (rebound to the
+// correct type).
+//
+// If an exception is thrown, the initialized elements are destroyed in reverse order of
+// initialization using allocator_traits destruction. If the elements in the range are C-style
+// arrays, they are initialized element-wise using allocator construction, and recursively so.
+template <class _Alloc,
+ class _BidirIter,
+ class _Tp,
+ class _Size = typename iterator_traits<_BidirIter>::difference_type>
+_LIBCPP_HIDE_FROM_ABI constexpr void
+__uninitialized_allocator_fill_n_multidimensional(_Alloc& __alloc, _BidirIter __it, _Size __n, _Tp const& __value) {
+ using _ValueType = typename iterator_traits<_BidirIter>::value_type;
+ __allocator_traits_rebind_t<_Alloc, _ValueType> __value_alloc(__alloc);
+ _BidirIter __begin = __it;
+
+ // If an exception is thrown, destroy what we have constructed so far in reverse order.
+ auto __guard =
+ std::__make_exception_guard([&]() { std::__allocator_destroy_multidimensional(__value_alloc, __begin, __it); });
+ for (; __n != 0; --__n, ++__it) {
+ std::__allocator_construct_at_multidimensional(__value_alloc, std::addressof(*__it), __value);
+ }
+ __guard.__complete();
+}
+
+// Same as __uninitialized_allocator_fill_n_multidimensional, but doesn't pass any initialization argument
+// to the allocator's construct method, which results in value initialization.
+template <class _Alloc, class _BidirIter, class _Size = typename iterator_traits<_BidirIter>::difference_type>
+_LIBCPP_HIDE_FROM_ABI constexpr void
+__uninitialized_allocator_value_construct_n_multidimensional(_Alloc& __alloc, _BidirIter __it, _Size __n) {
+ using _ValueType = typename iterator_traits<_BidirIter>::value_type;
+ __allocator_traits_rebind_t<_Alloc, _ValueType> __value_alloc(__alloc);
+ _BidirIter __begin = __it;
+
+ // If an exception is thrown, destroy what we have constructed so far in reverse order.
+ auto __guard =
+ std::__make_exception_guard([&]() { std::__allocator_destroy_multidimensional(__value_alloc, __begin, __it); });
+ for (; __n != 0; --__n, ++__it) {
+ std::__allocator_construct_at_multidimensional(__value_alloc, std::addressof(*__it));
+ }
+ __guard.__complete();
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+// Destroy all elements in [__first, __last) from left to right using allocator destruction.
+template <class _Alloc, class _Iter, class _Sent>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__allocator_destroy(_Alloc& __alloc, _Iter __first, _Sent __last) {
+ for (; __first != __last; ++__first)
+ allocator_traits<_Alloc>::destroy(__alloc, std::__to_address(__first));
+}
+
+template <class _Alloc, class _Iter>
+class _AllocatorDestroyRangeReverse {
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
+ _AllocatorDestroyRangeReverse(_Alloc& __alloc, _Iter& __first, _Iter& __last)
+ : __alloc_(__alloc), __first_(__first), __last_(__last) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void operator()() const {
+ std::__allocator_destroy(__alloc_, std::reverse_iterator<_Iter>(__last_), std::reverse_iterator<_Iter>(__first_));
+ }
+
+private:
+ _Alloc& __alloc_;
+ _Iter& __first_;
+ _Iter& __last_;
+};
+
+// Copy-construct [__first1, __last1) in [__first2, __first2 + N), where N is distance(__first1, __last1).
+//
+// The caller has to ensure that __first2 can hold at least N uninitialized elements. If an exception is thrown the
+// already copied elements are destroyed in reverse order of their construction.
+template <class _Alloc, class _Iter1, class _Sent1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter2
+__uninitialized_allocator_copy_impl(_Alloc& __alloc, _Iter1 __first1, _Sent1 __last1, _Iter2 __first2) {
+ auto __destruct_first = __first2;
+ auto __guard =
+ std::__make_exception_guard(_AllocatorDestroyRangeReverse<_Alloc, _Iter2>(__alloc, __destruct_first, __first2));
+ while (__first1 != __last1) {
+ allocator_traits<_Alloc>::construct(__alloc, std::__to_address(__first2), *__first1);
+ ++__first1;
+ ++__first2;
+ }
+ __guard.__complete();
+ return __first2;
+}
+
+template <class _Alloc, class _Type>
+struct __allocator_has_trivial_copy_construct : _Not<__has_construct<_Alloc, _Type*, const _Type&> > {};
+
+template <class _Type>
+struct __allocator_has_trivial_copy_construct<allocator<_Type>, _Type> : true_type {};
+
+template <class _Alloc,
+ class _In,
+ class _RawTypeIn = __remove_const_t<_In>,
+ class _Out,
+ __enable_if_t<
+ // using _RawTypeIn because of the allocator<T const> extension
+ is_trivially_copy_constructible<_RawTypeIn>::value && is_trivially_copy_assignable<_RawTypeIn>::value &&
+ is_same<__remove_const_t<_In>, __remove_const_t<_Out> >::value &&
+ __allocator_has_trivial_copy_construct<_Alloc, _RawTypeIn>::value,
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Out*
+__uninitialized_allocator_copy_impl(_Alloc&, _In* __first1, _In* __last1, _Out* __first2) {
+ // TODO: Remove the const_cast once we drop support for std::allocator<T const>
+ if (__libcpp_is_constant_evaluated()) {
+ while (__first1 != __last1) {
+ std::__construct_at(std::__to_address(__first2), *__first1);
+ ++__first1;
+ ++__first2;
+ }
+ return __first2;
+ } else {
+ return std::copy(__first1, __last1, const_cast<_RawTypeIn*>(__first2));
+ }
+}
+
+template <class _Alloc, class _Iter1, class _Sent1, class _Iter2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter2
+__uninitialized_allocator_copy(_Alloc& __alloc, _Iter1 __first1, _Sent1 __last1, _Iter2 __first2) {
+ auto __unwrapped_range = std::__unwrap_range(__first1, __last1);
+ auto __result = std::__uninitialized_allocator_copy_impl(
+ __alloc, __unwrapped_range.first, __unwrapped_range.second, std::__unwrap_iter(__first2));
+ return std::__rewrap_iter(__first2, __result);
+}
+
+template <class _Alloc, class _Type>
+struct __allocator_has_trivial_move_construct : _Not<__has_construct<_Alloc, _Type*, _Type&&> > {};
+
+template <class _Type>
+struct __allocator_has_trivial_move_construct<allocator<_Type>, _Type> : true_type {};
+
+template <class _Alloc, class _Tp>
+struct __allocator_has_trivial_destroy : _Not<__has_destroy<_Alloc, _Tp*> > {};
+
+template <class _Tp, class _Up>
+struct __allocator_has_trivial_destroy<allocator<_Tp>, _Up> : true_type {};
+
+// __uninitialized_allocator_relocate relocates the objects in [__first, __last) into __result.
+// Relocation means that the objects in [__first, __last) are placed into __result as-if by move-construct and destroy,
+// except that the move constructor and destructor may never be called if they are known to be equivalent to a memcpy.
+//
+// Preconditions: __result doesn't contain any objects and [__first, __last) contains objects
+// Postconditions: __result contains the objects from [__first, __last) and
+// [__first, __last) doesn't contain any objects
+//
+// The strong exception guarantee is provided if any of the following are true:
+// - is_nothrow_move_constructible<_Tp>
+// - is_copy_constructible<_Tp>
+// - __libcpp_is_trivially_relocatable<_Tp>
+template <class _Alloc, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__uninitialized_allocator_relocate(_Alloc& __alloc, _Tp* __first, _Tp* __last, _Tp* __result) {
+ static_assert(__is_cpp17_move_insertable<_Alloc>::value,
+ "The specified type does not meet the requirements of Cpp17MoveInsertable");
+ if (__libcpp_is_constant_evaluated() || !__libcpp_is_trivially_relocatable<_Tp>::value ||
+ !__allocator_has_trivial_move_construct<_Alloc, _Tp>::value ||
+ !__allocator_has_trivial_destroy<_Alloc, _Tp>::value) {
+ auto __destruct_first = __result;
+ auto __guard =
+ std::__make_exception_guard(_AllocatorDestroyRangeReverse<_Alloc, _Tp*>(__alloc, __destruct_first, __result));
+ auto __iter = __first;
+ while (__iter != __last) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ allocator_traits<_Alloc>::construct(__alloc, __result, std::move_if_noexcept(*__iter));
+#else
+ allocator_traits<_Alloc>::construct(__alloc, __result, std::move(*__iter));
+#endif
+ ++__iter;
+ ++__result;
+ }
+ __guard.__complete();
+ std::__allocator_destroy(__alloc, __first, __last);
+ } else {
+ __builtin_memcpy(const_cast<__remove_const_t<_Tp>*>(__result), __first, sizeof(_Tp) * (__last - __first));
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_UNINITIALIZED_ALGORITHMS_H
diff --git a/libcxx/include/__cxx03/__memory/unique_ptr.h b/libcxx/include/__cxx03/__memory/unique_ptr.h
new file mode 100644
index 00000000000000..f75259473efb12
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/unique_ptr.h
@@ -0,0 +1,693 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_UNIQUE_PTR_H
+#define _LIBCPP___MEMORY_UNIQUE_PTR_H
+
+#include <__compare/compare_three_way.h>
+#include <__compare/compare_three_way_result.h>
+#include <__compare/three_way_comparable.h>
+#include <__config>
+#include <__functional/hash.h>
+#include <__functional/operations.h>
+#include <__memory/allocator_traits.h> // __pointer
+#include <__memory/auto_ptr.h>
+#include <__memory/compressed_pair.h>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/dependent_type.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/remove_extent.h>
+#include <__type_traits/remove_pointer.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Ptr>
+struct __is_noexcept_deref_or_void {
+ static constexpr bool value = noexcept(*std::declval<_Ptr>());
+};
+
+template <>
+struct __is_noexcept_deref_or_void<void*> : true_type {};
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS default_delete {
+ static_assert(!is_function<_Tp>::value, "default_delete cannot be instantiated for function types");
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI constexpr default_delete() _NOEXCEPT = default;
+#else
+ _LIBCPP_HIDE_FROM_ABI default_delete() {}
+#endif
+ template <class _Up, __enable_if_t<is_convertible<_Up*, _Tp*>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 default_delete(const default_delete<_Up>&) _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator()(_Tp* __ptr) const _NOEXCEPT {
+ static_assert(sizeof(_Tp) >= 0, "cannot delete an incomplete type");
+ static_assert(!is_void<_Tp>::value, "cannot delete an incomplete type");
+ delete __ptr;
+ }
+};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS default_delete<_Tp[]> {
+private:
+ template <class _Up>
+ struct _EnableIfConvertible : enable_if<is_convertible<_Up (*)[], _Tp (*)[]>::value> {};
+
+public:
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI constexpr default_delete() _NOEXCEPT = default;
+#else
+ _LIBCPP_HIDE_FROM_ABI default_delete() {}
+#endif
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23
+ default_delete(const default_delete<_Up[]>&, typename _EnableIfConvertible<_Up>::type* = 0) _NOEXCEPT {}
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 typename _EnableIfConvertible<_Up>::type
+ operator()(_Up* __ptr) const _NOEXCEPT {
+ static_assert(sizeof(_Up) >= 0, "cannot delete an incomplete type");
+ delete[] __ptr;
+ }
+};
+
+template <class _Deleter>
+struct __unique_ptr_deleter_sfinae {
+ static_assert(!is_reference<_Deleter>::value, "incorrect specialization");
+ typedef const _Deleter& __lval_ref_type;
+ typedef _Deleter&& __good_rval_ref_type;
+ typedef true_type __enable_rval_overload;
+};
+
+template <class _Deleter>
+struct __unique_ptr_deleter_sfinae<_Deleter const&> {
+ typedef const _Deleter& __lval_ref_type;
+ typedef const _Deleter&& __bad_rval_ref_type;
+ typedef false_type __enable_rval_overload;
+};
+
+template <class _Deleter>
+struct __unique_ptr_deleter_sfinae<_Deleter&> {
+ typedef _Deleter& __lval_ref_type;
+ typedef _Deleter&& __bad_rval_ref_type;
+ typedef false_type __enable_rval_overload;
+};
+
+#if defined(_LIBCPP_ABI_ENABLE_UNIQUE_PTR_TRIVIAL_ABI)
+# define _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI __attribute__((__trivial_abi__))
+#else
+# define _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI
+#endif
+
+template <class _Tp, class _Dp = default_delete<_Tp> >
+class _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS unique_ptr {
+public:
+ typedef _Tp element_type;
+ typedef _Dp deleter_type;
+ typedef _LIBCPP_NODEBUG typename __pointer<_Tp, deleter_type>::type pointer;
+
+ static_assert(!is_rvalue_reference<deleter_type>::value, "the specified deleter type cannot be an rvalue reference");
+
+ // A unique_ptr contains the following members which may be trivially relocatable:
+ // - pointer : this may be trivially relocatable, so it's checked
+ // - deleter_type: this may be trivially relocatable, so it's checked
+ //
+ // This unique_ptr implementation only contains a pointer to the unique object and a deleter, so there are no
+ // references to itself. This means that the entire structure is trivially relocatable if its members are.
+ using __trivially_relocatable = __conditional_t<
+ __libcpp_is_trivially_relocatable<pointer>::value && __libcpp_is_trivially_relocatable<deleter_type>::value,
+ unique_ptr,
+ void>;
+
+private:
+ __compressed_pair<pointer, deleter_type> __ptr_;
+
+ typedef _LIBCPP_NODEBUG __unique_ptr_deleter_sfinae<_Dp> _DeleterSFINAE;
+
+ template <bool _Dummy>
+ using _LValRefType _LIBCPP_NODEBUG = typename __dependent_type<_DeleterSFINAE, _Dummy>::__lval_ref_type;
+
+ template <bool _Dummy>
+ using _GoodRValRefType _LIBCPP_NODEBUG = typename __dependent_type<_DeleterSFINAE, _Dummy>::__good_rval_ref_type;
+
+ template <bool _Dummy>
+ using _BadRValRefType _LIBCPP_NODEBUG = typename __dependent_type<_DeleterSFINAE, _Dummy>::__bad_rval_ref_type;
+
+ template <bool _Dummy, class _Deleter = typename __dependent_type< __type_identity<deleter_type>, _Dummy>::type>
+ using _EnableIfDeleterDefaultConstructible _LIBCPP_NODEBUG =
+ __enable_if_t<is_default_constructible<_Deleter>::value && !is_pointer<_Deleter>::value>;
+
+ template <class _ArgType>
+ using _EnableIfDeleterConstructible _LIBCPP_NODEBUG = __enable_if_t<is_constructible<deleter_type, _ArgType>::value>;
+
+ template <class _UPtr, class _Up>
+ using _EnableIfMoveConvertible _LIBCPP_NODEBUG =
+ __enable_if_t< is_convertible<typename _UPtr::pointer, pointer>::value && !is_array<_Up>::value >;
+
+ template <class _UDel>
+ using _EnableIfDeleterConvertible _LIBCPP_NODEBUG =
+ __enable_if_t< (is_reference<_Dp>::value && is_same<_Dp, _UDel>::value) ||
+ (!is_reference<_Dp>::value && is_convertible<_UDel, _Dp>::value) >;
+
+ template <class _UDel>
+ using _EnableIfDeleterAssignable = __enable_if_t< is_assignable<_Dp&, _UDel&&>::value >;
+
+public:
+ template <bool _Dummy = true, class = _EnableIfDeleterDefaultConstructible<_Dummy> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT : __ptr_(__value_init_tag(), __value_init_tag()) {}
+
+ template <bool _Dummy = true, class = _EnableIfDeleterDefaultConstructible<_Dummy> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
+ : __ptr_(__value_init_tag(), __value_init_tag()) {}
+
+ template <bool _Dummy = true, class = _EnableIfDeleterDefaultConstructible<_Dummy> >
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit unique_ptr(pointer __p) _NOEXCEPT : __ptr_(__p, __value_init_tag()) {}
+
+ template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_LValRefType<_Dummy> > >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(pointer __p, _LValRefType<_Dummy> __d) _NOEXCEPT
+ : __ptr_(__p, __d) {}
+
+ template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> > >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(pointer __p, _GoodRValRefType<_Dummy> __d) _NOEXCEPT
+ : __ptr_(__p, std::move(__d)) {
+ static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
+ }
+
+ template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_BadRValRefType<_Dummy> > >
+ _LIBCPP_HIDE_FROM_ABI unique_ptr(pointer __p, _BadRValRefType<_Dummy> __d) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(unique_ptr&& __u) _NOEXCEPT
+ : __ptr_(__u.release(), std::forward<deleter_type>(__u.get_deleter())) {}
+
+ template <class _Up,
+ class _Ep,
+ class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
+ class = _EnableIfDeleterConvertible<_Ep> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
+ : __ptr_(__u.release(), std::forward<_Ep>(__u.get_deleter())) {}
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
+ template <class _Up,
+ __enable_if_t<is_convertible<_Up*, _Tp*>::value && is_same<_Dp, default_delete<_Tp> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI unique_ptr(auto_ptr<_Up>&& __p) _NOEXCEPT : __ptr_(__p.release(), __value_init_tag()) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT {
+ reset(__u.release());
+ __ptr_.second() = std::forward<deleter_type>(__u.get_deleter());
+ return *this;
+ }
+
+ template <class _Up,
+ class _Ep,
+ class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
+ class = _EnableIfDeleterAssignable<_Ep> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT {
+ reset(__u.release());
+ __ptr_.second() = std::forward<_Ep>(__u.get_deleter());
+ return *this;
+ }
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
+ template <class _Up,
+ __enable_if_t<is_convertible<_Up*, _Tp*>::value && is_same<_Dp, default_delete<_Tp> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI unique_ptr& operator=(auto_ptr<_Up> __p) {
+ reset(__p.release());
+ return *this;
+ }
+#endif
+
+#ifdef _LIBCPP_CXX03_LANG
+ unique_ptr(unique_ptr const&) = delete;
+ unique_ptr& operator=(unique_ptr const&) = delete;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 ~unique_ptr() { reset(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(nullptr_t) _NOEXCEPT {
+ reset();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 __add_lvalue_reference_t<_Tp> operator*() const
+ _NOEXCEPT_(__is_noexcept_deref_or_void<pointer>::value) {
+ return *__ptr_.first();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer operator->() const _NOEXCEPT { return __ptr_.first(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer get() const _NOEXCEPT { return __ptr_.first(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 deleter_type& get_deleter() _NOEXCEPT { return __ptr_.second(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 const deleter_type& get_deleter() const _NOEXCEPT {
+ return __ptr_.second();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit operator bool() const _NOEXCEPT {
+ return __ptr_.first() != nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer release() _NOEXCEPT {
+ pointer __t = __ptr_.first();
+ __ptr_.first() = pointer();
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void reset(pointer __p = pointer()) _NOEXCEPT {
+ pointer __tmp = __ptr_.first();
+ __ptr_.first() = __p;
+ if (__tmp)
+ __ptr_.second()(__tmp);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void swap(unique_ptr& __u) _NOEXCEPT { __ptr_.swap(__u.__ptr_); }
+};
+
+template <class _Tp, class _Dp>
+class _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS unique_ptr<_Tp[], _Dp> {
+public:
+ typedef _Tp element_type;
+ typedef _Dp deleter_type;
+ typedef typename __pointer<_Tp, deleter_type>::type pointer;
+
+ // A unique_ptr contains the following members which may be trivially relocatable:
+ // - pointer : this may be trivially relocatable, so it's checked
+ // - deleter_type: this may be trivially relocatable, so it's checked
+ //
+ // This unique_ptr implementation only contains a pointer to the unique object and a deleter, so there are no
+ // references to itself. This means that the entire structure is trivially relocatable if its members are.
+ using __trivially_relocatable = __conditional_t<
+ __libcpp_is_trivially_relocatable<pointer>::value && __libcpp_is_trivially_relocatable<deleter_type>::value,
+ unique_ptr,
+ void>;
+
+private:
+ __compressed_pair<pointer, deleter_type> __ptr_;
+
+ template <class _From>
+ struct _CheckArrayPointerConversion : is_same<_From, pointer> {};
+
+ template <class _FromElem>
+ struct _CheckArrayPointerConversion<_FromElem*>
+ : integral_constant<bool,
+ is_same<_FromElem*, pointer>::value ||
+ (is_same<pointer, element_type*>::value &&
+ is_convertible<_FromElem (*)[], element_type (*)[]>::value) > {};
+
+ typedef __unique_ptr_deleter_sfinae<_Dp> _DeleterSFINAE;
+
+ template <bool _Dummy>
+ using _LValRefType _LIBCPP_NODEBUG = typename __dependent_type<_DeleterSFINAE, _Dummy>::__lval_ref_type;
+
+ template <bool _Dummy>
+ using _GoodRValRefType _LIBCPP_NODEBUG = typename __dependent_type<_DeleterSFINAE, _Dummy>::__good_rval_ref_type;
+
+ template <bool _Dummy>
+ using _BadRValRefType _LIBCPP_NODEBUG = typename __dependent_type<_DeleterSFINAE, _Dummy>::__bad_rval_ref_type;
+
+ template <bool _Dummy, class _Deleter = typename __dependent_type< __type_identity<deleter_type>, _Dummy>::type>
+ using _EnableIfDeleterDefaultConstructible _LIBCPP_NODEBUG =
+ __enable_if_t<is_default_constructible<_Deleter>::value && !is_pointer<_Deleter>::value>;
+
+ template <class _ArgType>
+ using _EnableIfDeleterConstructible _LIBCPP_NODEBUG = __enable_if_t<is_constructible<deleter_type, _ArgType>::value>;
+
+ template <class _Pp>
+ using _EnableIfPointerConvertible _LIBCPP_NODEBUG = __enable_if_t< _CheckArrayPointerConversion<_Pp>::value >;
+
+ template <class _UPtr, class _Up, class _ElemT = typename _UPtr::element_type>
+ using _EnableIfMoveConvertible _LIBCPP_NODEBUG =
+ __enable_if_t< is_array<_Up>::value && is_same<pointer, element_type*>::value &&
+ is_same<typename _UPtr::pointer, _ElemT*>::value &&
+ is_convertible<_ElemT (*)[], element_type (*)[]>::value >;
+
+ template <class _UDel>
+ using _EnableIfDeleterConvertible _LIBCPP_NODEBUG =
+ __enable_if_t< (is_reference<_Dp>::value && is_same<_Dp, _UDel>::value) ||
+ (!is_reference<_Dp>::value && is_convertible<_UDel, _Dp>::value) >;
+
+ template <class _UDel>
+ using _EnableIfDeleterAssignable _LIBCPP_NODEBUG = __enable_if_t< is_assignable<_Dp&, _UDel&&>::value >;
+
+public:
+ template <bool _Dummy = true, class = _EnableIfDeleterDefaultConstructible<_Dummy> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT : __ptr_(__value_init_tag(), __value_init_tag()) {}
+
+ template <bool _Dummy = true, class = _EnableIfDeleterDefaultConstructible<_Dummy> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
+ : __ptr_(__value_init_tag(), __value_init_tag()) {}
+
+ template <class _Pp,
+ bool _Dummy = true,
+ class = _EnableIfDeleterDefaultConstructible<_Dummy>,
+ class = _EnableIfPointerConvertible<_Pp> >
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit unique_ptr(_Pp __p) _NOEXCEPT : __ptr_(__p, __value_init_tag()) {}
+
+ template <class _Pp,
+ bool _Dummy = true,
+ class = _EnableIfDeleterConstructible<_LValRefType<_Dummy> >,
+ class = _EnableIfPointerConvertible<_Pp> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(_Pp __p, _LValRefType<_Dummy> __d) _NOEXCEPT
+ : __ptr_(__p, __d) {}
+
+ template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_LValRefType<_Dummy> > >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(nullptr_t, _LValRefType<_Dummy> __d) _NOEXCEPT
+ : __ptr_(nullptr, __d) {}
+
+ template <class _Pp,
+ bool _Dummy = true,
+ class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> >,
+ class = _EnableIfPointerConvertible<_Pp> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(_Pp __p, _GoodRValRefType<_Dummy> __d) _NOEXCEPT
+ : __ptr_(__p, std::move(__d)) {
+ static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
+ }
+
+ template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> > >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(nullptr_t, _GoodRValRefType<_Dummy> __d) _NOEXCEPT
+ : __ptr_(nullptr, std::move(__d)) {
+ static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
+ }
+
+ template <class _Pp,
+ bool _Dummy = true,
+ class = _EnableIfDeleterConstructible<_BadRValRefType<_Dummy> >,
+ class = _EnableIfPointerConvertible<_Pp> >
+ _LIBCPP_HIDE_FROM_ABI unique_ptr(_Pp __p, _BadRValRefType<_Dummy> __d) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(unique_ptr&& __u) _NOEXCEPT
+ : __ptr_(__u.release(), std::forward<deleter_type>(__u.get_deleter())) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT {
+ reset(__u.release());
+ __ptr_.second() = std::forward<deleter_type>(__u.get_deleter());
+ return *this;
+ }
+
+ template <class _Up,
+ class _Ep,
+ class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
+ class = _EnableIfDeleterConvertible<_Ep> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
+ : __ptr_(__u.release(), std::forward<_Ep>(__u.get_deleter())) {}
+
+ template <class _Up,
+ class _Ep,
+ class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
+ class = _EnableIfDeleterAssignable<_Ep> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT {
+ reset(__u.release());
+ __ptr_.second() = std::forward<_Ep>(__u.get_deleter());
+ return *this;
+ }
+
+#ifdef _LIBCPP_CXX03_LANG
+ unique_ptr(unique_ptr const&) = delete;
+ unique_ptr& operator=(unique_ptr const&) = delete;
+#endif
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 ~unique_ptr() { reset(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(nullptr_t) _NOEXCEPT {
+ reset();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 __add_lvalue_reference_t<_Tp> operator[](size_t __i) const {
+ return __ptr_.first()[__i];
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer get() const _NOEXCEPT { return __ptr_.first(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 deleter_type& get_deleter() _NOEXCEPT { return __ptr_.second(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 const deleter_type& get_deleter() const _NOEXCEPT {
+ return __ptr_.second();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit operator bool() const _NOEXCEPT {
+ return __ptr_.first() != nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer release() _NOEXCEPT {
+ pointer __t = __ptr_.first();
+ __ptr_.first() = pointer();
+ return __t;
+ }
+
+ template <class _Pp, __enable_if_t<_CheckArrayPointerConversion<_Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void reset(_Pp __p) _NOEXCEPT {
+ pointer __tmp = __ptr_.first();
+ __ptr_.first() = __p;
+ if (__tmp)
+ __ptr_.second()(__tmp);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void reset(nullptr_t = nullptr) _NOEXCEPT {
+ pointer __tmp = __ptr_.first();
+ __ptr_.first() = nullptr;
+ if (__tmp)
+ __ptr_.second()(__tmp);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void swap(unique_ptr& __u) _NOEXCEPT { __ptr_.swap(__u.__ptr_); }
+};
+
+template <class _Tp, class _Dp, __enable_if_t<__is_swappable_v<_Dp>, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void
+swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+template <class _T1, class _D1, class _T2, class _D2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
+operator==(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
+ return __x.get() == __y.get();
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _T1, class _D1, class _T2, class _D2>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
+ return !(__x == __y);
+}
+#endif
+
+template <class _T1, class _D1, class _T2, class _D2>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
+ typedef typename unique_ptr<_T1, _D1>::pointer _P1;
+ typedef typename unique_ptr<_T2, _D2>::pointer _P2;
+ typedef typename common_type<_P1, _P2>::type _Vp;
+ return less<_Vp>()(__x.get(), __y.get());
+}
+
+template <class _T1, class _D1, class _T2, class _D2>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
+ return __y < __x;
+}
+
+template <class _T1, class _D1, class _T2, class _D2>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
+ return !(__y < __x);
+}
+
+template <class _T1, class _D1, class _T2, class _D2>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
+ return !(__x < __y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _T1, class _D1, class _T2, class _D2>
+ requires three_way_comparable_with<typename unique_ptr<_T1, _D1>::pointer, typename unique_ptr<_T2, _D2>::pointer>
+_LIBCPP_HIDE_FROM_ABI
+compare_three_way_result_t<typename unique_ptr<_T1, _D1>::pointer, typename unique_ptr<_T2, _D2>::pointer>
+operator<=>(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
+ return compare_three_way()(__x.get(), __y.get());
+}
+#endif
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
+operator==(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT {
+ return !__x;
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT {
+ return !__x;
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT {
+ return static_cast<bool>(__x);
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT {
+ return static_cast<bool>(__x);
+}
+#endif // _LIBCPP_STD_VER <= 17
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator<(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
+ typedef typename unique_ptr<_T1, _D1>::pointer _P1;
+ return less<_P1>()(__x.get(), nullptr);
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator<(nullptr_t, const unique_ptr<_T1, _D1>& __x) {
+ typedef typename unique_ptr<_T1, _D1>::pointer _P1;
+ return less<_P1>()(nullptr, __x.get());
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator>(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
+ return nullptr < __x;
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator>(nullptr_t, const unique_ptr<_T1, _D1>& __x) {
+ return __x < nullptr;
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator<=(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
+ return !(nullptr < __x);
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator<=(nullptr_t, const unique_ptr<_T1, _D1>& __x) {
+ return !(__x < nullptr);
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator>=(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
+ return !(__x < nullptr);
+}
+
+template <class _T1, class _D1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x) {
+ return !(nullptr < __x);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _T1, class _D1>
+ requires three_way_comparable< typename unique_ptr<_T1, _D1>::pointer>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 compare_three_way_result_t<typename unique_ptr<_T1, _D1>::pointer>
+operator<=>(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
+ return compare_three_way()(__x.get(), static_cast<typename unique_ptr<_T1, _D1>::pointer>(nullptr));
+}
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+
+template <class _Tp>
+struct __unique_if {
+ typedef unique_ptr<_Tp> __unique_single;
+};
+
+template <class _Tp>
+struct __unique_if<_Tp[]> {
+ typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
+};
+
+template <class _Tp, size_t _Np>
+struct __unique_if<_Tp[_Np]> {
+ typedef void __unique_array_known_bound;
+};
+
+template <class _Tp, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 typename __unique_if<_Tp>::__unique_single
+make_unique(_Args&&... __args) {
+ return unique_ptr<_Tp>(new _Tp(std::forward<_Args>(__args)...));
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 typename __unique_if<_Tp>::__unique_array_unknown_bound
+make_unique(size_t __n) {
+ typedef __remove_extent_t<_Tp> _Up;
+ return unique_ptr<_Tp>(new _Up[__n]());
+}
+
+template <class _Tp, class... _Args>
+typename __unique_if<_Tp>::__unique_array_known_bound make_unique(_Args&&...) = delete;
+
+#endif // _LIBCPP_STD_VER >= 14
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 typename __unique_if<_Tp>::__unique_single
+make_unique_for_overwrite() {
+ return unique_ptr<_Tp>(new _Tp);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 typename __unique_if<_Tp>::__unique_array_unknown_bound
+make_unique_for_overwrite(size_t __n) {
+ return unique_ptr<_Tp>(new __remove_extent_t<_Tp>[__n]);
+}
+
+template <class _Tp, class... _Args>
+typename __unique_if<_Tp>::__unique_array_known_bound make_unique_for_overwrite(_Args&&...) = delete;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS hash;
+
+template <class _Tp, class _Dp>
+#ifdef _LIBCPP_CXX03_LANG
+struct _LIBCPP_TEMPLATE_VIS hash<unique_ptr<_Tp, _Dp> >
+#else
+struct _LIBCPP_TEMPLATE_VIS hash<__enable_hash_helper< unique_ptr<_Tp, _Dp>, typename unique_ptr<_Tp, _Dp>::pointer> >
+#endif
+{
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef unique_ptr<_Tp, _Dp> argument_type;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef size_t result_type;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const unique_ptr<_Tp, _Dp>& __ptr) const {
+ typedef typename unique_ptr<_Tp, _Dp>::pointer pointer;
+ return hash<pointer>()(__ptr.get());
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_UNIQUE_PTR_H
diff --git a/libcxx/include/__cxx03/__memory/uses_allocator.h b/libcxx/include/__cxx03/__memory/uses_allocator.h
new file mode 100644
index 00000000000000..84310c3fa56739
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/uses_allocator.h
@@ -0,0 +1,52 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_USES_ALLOCATOR_H
+#define _LIBCPP___MEMORY_USES_ALLOCATOR_H
+
+#include <__config>
+#include <__type_traits/is_convertible.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __has_allocator_type {
+private:
+ template <class _Up>
+ static false_type __test(...);
+ template <class _Up>
+ static true_type __test(typename _Up::allocator_type* = 0);
+
+public:
+ static const bool value = decltype(__test<_Tp>(0))::value;
+};
+
+template <class _Tp, class _Alloc, bool = __has_allocator_type<_Tp>::value>
+struct __uses_allocator : public integral_constant<bool, is_convertible<_Alloc, typename _Tp::allocator_type>::value> {
+};
+
+template <class _Tp, class _Alloc>
+struct __uses_allocator<_Tp, _Alloc, false> : public false_type {};
+
+template <class _Tp, class _Alloc>
+struct _LIBCPP_TEMPLATE_VIS uses_allocator : public __uses_allocator<_Tp, _Alloc> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class _Alloc>
+inline constexpr bool uses_allocator_v = uses_allocator<_Tp, _Alloc>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_USES_ALLOCATOR_H
diff --git a/libcxx/include/__cxx03/__memory/uses_allocator_construction.h b/libcxx/include/__cxx03/__memory/uses_allocator_construction.h
new file mode 100644
index 00000000000000..5e5819d4c281e4
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/uses_allocator_construction.h
@@ -0,0 +1,247 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_USES_ALLOCATOR_CONSTRUCTION_H
+#define _LIBCPP___MEMORY_USES_ALLOCATOR_CONSTRUCTION_H
+
+#include <__config>
+#include <__memory/construct_at.h>
+#include <__memory/uses_allocator.h>
+#include <__tuple/tuple_like_no_subrange.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cv.h>
+#include <__utility/declval.h>
+#include <__utility/pair.h>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Type>
+inline constexpr bool __is_std_pair = false;
+
+template <class _Type1, class _Type2>
+inline constexpr bool __is_std_pair<pair<_Type1, _Type2>> = true;
+
+template <class _Tp>
+inline constexpr bool __is_cv_std_pair = __is_std_pair<remove_cv_t<_Tp>>;
+
+template <class _Type, class _Alloc, class... _Args, __enable_if_t<!__is_cv_std_pair<_Type>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _Args&&... __args) noexcept {
+ if constexpr (!uses_allocator_v<remove_cv_t<_Type>, _Alloc> && is_constructible_v<_Type, _Args...>) {
+ return std::forward_as_tuple(std::forward<_Args>(__args)...);
+ } else if constexpr (uses_allocator_v<remove_cv_t<_Type>, _Alloc> &&
+ is_constructible_v<_Type, allocator_arg_t, const _Alloc&, _Args...>) {
+ return tuple<allocator_arg_t, const _Alloc&, _Args&&...>(allocator_arg, __alloc, std::forward<_Args>(__args)...);
+ } else if constexpr (uses_allocator_v<remove_cv_t<_Type>, _Alloc> &&
+ is_constructible_v<_Type, _Args..., const _Alloc&>) {
+ return std::forward_as_tuple(std::forward<_Args>(__args)..., __alloc);
+ } else {
+ static_assert(
+ sizeof(_Type) + 1 == 0, "If uses_allocator_v<Type> is true, the type has to be allocator-constructible");
+ }
+}
+
+template <class _Pair, class _Alloc, class _Tuple1, class _Tuple2, __enable_if_t<__is_cv_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __uses_allocator_construction_args(
+ const _Alloc& __alloc, piecewise_construct_t, _Tuple1&& __x, _Tuple2&& __y) noexcept {
+ return std::make_tuple(
+ piecewise_construct,
+ std::apply(
+ [&__alloc](auto&&... __args1) {
+ return std::__uses_allocator_construction_args<typename _Pair::first_type>(
+ __alloc, std::forward<decltype(__args1)>(__args1)...);
+ },
+ std::forward<_Tuple1>(__x)),
+ std::apply(
+ [&__alloc](auto&&... __args2) {
+ return std::__uses_allocator_construction_args<typename _Pair::second_type>(
+ __alloc, std::forward<decltype(__args2)>(__args2)...);
+ },
+ std::forward<_Tuple2>(__y)));
+}
+
+template <class _Pair, class _Alloc, __enable_if_t<__is_cv_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __uses_allocator_construction_args(const _Alloc& __alloc) noexcept {
+ return std::__uses_allocator_construction_args<_Pair>(__alloc, piecewise_construct, tuple<>{}, tuple<>{});
+}
+
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_cv_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _Up&& __u, _Vp&& __v) noexcept {
+ return std::__uses_allocator_construction_args<_Pair>(
+ __alloc,
+ piecewise_construct,
+ std::forward_as_tuple(std::forward<_Up>(__u)),
+ std::forward_as_tuple(std::forward<_Vp>(__v)));
+}
+
+# if _LIBCPP_STD_VER >= 23
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_cv_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, pair<_Up, _Vp>& __pair) noexcept {
+ return std::__uses_allocator_construction_args<_Pair>(
+ __alloc, piecewise_construct, std::forward_as_tuple(__pair.first), std::forward_as_tuple(__pair.second));
+}
+# endif
+
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_cv_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, const pair<_Up, _Vp>& __pair) noexcept {
+ return std::__uses_allocator_construction_args<_Pair>(
+ __alloc, piecewise_construct, std::forward_as_tuple(__pair.first), std::forward_as_tuple(__pair.second));
+}
+
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_cv_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, pair<_Up, _Vp>&& __pair) noexcept {
+ return std::__uses_allocator_construction_args<_Pair>(
+ __alloc,
+ piecewise_construct,
+ std::forward_as_tuple(std::get<0>(std::move(__pair))),
+ std::forward_as_tuple(std::get<1>(std::move(__pair))));
+}
+
+# if _LIBCPP_STD_VER >= 23
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_cv_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, const pair<_Up, _Vp>&& __pair) noexcept {
+ return std::__uses_allocator_construction_args<_Pair>(
+ __alloc,
+ piecewise_construct,
+ std::forward_as_tuple(std::get<0>(std::move(__pair))),
+ std::forward_as_tuple(std::get<1>(std::move(__pair))));
+}
+
+template <class _Pair, class _Alloc, __pair_like_no_subrange _PairLike, __enable_if_t<__is_cv_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _PairLike&& __p) noexcept {
+ return std::__uses_allocator_construction_args<_Pair>(
+ __alloc,
+ piecewise_construct,
+ std::forward_as_tuple(std::get<0>(std::forward<_PairLike>(__p))),
+ std::forward_as_tuple(std::get<1>(std::forward<_PairLike>(__p))));
+}
+# endif
+
+namespace __uses_allocator_detail {
+
+template <class _Ap, class _Bp>
+void __fun(const pair<_Ap, _Bp>&);
+
+template <class _Tp>
+decltype(__uses_allocator_detail::__fun(std::declval<_Tp>()), true_type()) __convertible_to_const_pair_ref_impl(int);
+
+template <class>
+false_type __convertible_to_const_pair_ref_impl(...);
+
+template <class _Tp>
+inline constexpr bool __convertible_to_const_pair_ref =
+ decltype(__uses_allocator_detail::__convertible_to_const_pair_ref_impl<_Tp>(0))::value;
+
+# if _LIBCPP_STD_VER >= 23
+template <class _Tp, class _Up>
+inline constexpr bool __uses_allocator_constraints =
+ __is_cv_std_pair<_Tp> && !__pair_like_no_subrange<_Up> && !__convertible_to_const_pair_ref<_Up>;
+# else
+template <class _Tp, class _Up>
+inline constexpr bool __uses_allocator_constraints = __is_cv_std_pair<_Tp> && !__convertible_to_const_pair_ref<_Up>;
+# endif
+
+} // namespace __uses_allocator_detail
+
+template < class _Pair,
+ class _Alloc,
+ class _Type,
+ __enable_if_t<__uses_allocator_detail::__uses_allocator_constraints<_Pair, _Type>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _Type&& __value) noexcept;
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr _Type __make_obj_using_allocator(const _Alloc& __alloc, _Args&&... __args);
+
+template < class _Pair,
+ class _Alloc,
+ class _Type,
+ __enable_if_t< __uses_allocator_detail::__uses_allocator_constraints<_Pair, _Type>, int>>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _Type&& __value) noexcept {
+ struct __pair_constructor {
+ using _PairMutable = remove_cv_t<_Pair>;
+
+ _LIBCPP_HIDDEN constexpr auto __do_construct(const _PairMutable& __pair) const {
+ return std::__make_obj_using_allocator<_PairMutable>(__alloc_, __pair);
+ }
+
+ _LIBCPP_HIDDEN constexpr auto __do_construct(_PairMutable&& __pair) const {
+ return std::__make_obj_using_allocator<_PairMutable>(__alloc_, std::move(__pair));
+ }
+
+ const _Alloc& __alloc_;
+ _Type& __value_;
+
+ _LIBCPP_HIDDEN constexpr operator _PairMutable() const { return __do_construct(std::forward<_Type>(__value_)); }
+ };
+
+ return std::make_tuple(__pair_constructor{__alloc, __value});
+}
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr _Type __make_obj_using_allocator(const _Alloc& __alloc, _Args&&... __args) {
+ return std::make_from_tuple<_Type>(
+ std::__uses_allocator_construction_args<_Type>(__alloc, std::forward<_Args>(__args)...));
+}
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr _Type*
+__uninitialized_construct_using_allocator(_Type* __ptr, const _Alloc& __alloc, _Args&&... __args) {
+ return std::apply(
+ [&__ptr](auto&&... __xs) { return std::__construct_at(__ptr, std::forward<decltype(__xs)>(__xs)...); },
+ std::__uses_allocator_construction_args<_Type>(__alloc, std::forward<_Args>(__args)...));
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr auto uses_allocator_construction_args(const _Alloc& __alloc, _Args&&... __args) noexcept
+ -> decltype(std::__uses_allocator_construction_args<_Type>(__alloc, std::forward<_Args>(__args)...)) {
+ return /*--*/ std::__uses_allocator_construction_args<_Type>(__alloc, std::forward<_Args>(__args)...);
+}
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr auto make_obj_using_allocator(const _Alloc& __alloc, _Args&&... __args)
+ -> decltype(std::__make_obj_using_allocator<_Type>(__alloc, std::forward<_Args>(__args)...)) {
+ return /*--*/ std::__make_obj_using_allocator<_Type>(__alloc, std::forward<_Args>(__args)...);
+}
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+uninitialized_construct_using_allocator(_Type* __ptr, const _Alloc& __alloc, _Args&&... __args)
+ -> decltype(std::__uninitialized_construct_using_allocator(__ptr, __alloc, std::forward<_Args>(__args)...)) {
+ return /*--*/ std::__uninitialized_construct_using_allocator(__ptr, __alloc, std::forward<_Args>(__args)...);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_USES_ALLOCATOR_CONSTRUCTION_H
diff --git a/libcxx/include/__cxx03/__memory/voidify.h b/libcxx/include/__cxx03/__memory/voidify.h
new file mode 100644
index 00000000000000..dbd083bd8c1e9a
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory/voidify.h
@@ -0,0 +1,30 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_VOIDIFY_H
+#define _LIBCPP___MEMORY_VOIDIFY_H
+
+#include <__config>
+#include <__memory/addressof.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <typename _Tp>
+_LIBCPP_ALWAYS_INLINE _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void* __voidify(_Tp& __from) {
+ // Cast away cv-qualifiers to allow modifying elements of a range through const iterators.
+ return const_cast<void*>(static_cast<const volatile void*>(std::addressof(__from)));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_VOIDIFY_H
diff --git a/libcxx/include/__cxx03/__memory_resource/memory_resource.h b/libcxx/include/__cxx03/__memory_resource/memory_resource.h
new file mode 100644
index 00000000000000..ea85e50cd568bc
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory_resource/memory_resource.h
@@ -0,0 +1,88 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RESOURCE_MEMORY_RESOURCE_H
+#define _LIBCPP___MEMORY_RESOURCE_MEMORY_RESOURCE_H
+
+#include <__config>
+#include <__fwd/memory_resource.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace pmr {
+
+// [mem.res.class]
+
+class _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI memory_resource {
+ static const size_t __max_align = alignof(max_align_t);
+
+public:
+ virtual ~memory_resource();
+
+ [[nodiscard]] [[using __gnu__: __returns_nonnull__, __alloc_size__(2), __alloc_align__(3)]]
+ _LIBCPP_HIDE_FROM_ABI void* allocate(size_t __bytes, size_t __align = __max_align) {
+ return do_allocate(__bytes, __align);
+ }
+
+ [[__gnu__::__nonnull__]] _LIBCPP_HIDE_FROM_ABI void
+ deallocate(void* __p, size_t __bytes, size_t __align = __max_align) {
+ do_deallocate(__p, __bytes, __align);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool is_equal(const memory_resource& __other) const noexcept { return do_is_equal(__other); }
+
+private:
+ virtual void* do_allocate(size_t, size_t) = 0;
+ virtual void do_deallocate(void*, size_t, size_t) = 0;
+ virtual bool do_is_equal(memory_resource const&) const noexcept = 0;
+};
+
+// [mem.res.eq]
+
+inline _LIBCPP_AVAILABILITY_PMR _LIBCPP_HIDE_FROM_ABI bool
+operator==(const memory_resource& __lhs, const memory_resource& __rhs) noexcept {
+ return &__lhs == &__rhs || __lhs.is_equal(__rhs);
+}
+
+# if _LIBCPP_STD_VER <= 17
+
+inline _LIBCPP_AVAILABILITY_PMR _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const memory_resource& __lhs, const memory_resource& __rhs) noexcept {
+ return !(__lhs == __rhs);
+}
+
+# endif
+
+// [mem.res.global]
+
+[[__gnu__::__returns_nonnull__]] _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI memory_resource*
+get_default_resource() noexcept;
+
+[[__gnu__::__returns_nonnull__]] _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI memory_resource*
+set_default_resource(memory_resource*) noexcept;
+
+[[using __gnu__: __returns_nonnull__, __const__]] _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI memory_resource*
+new_delete_resource() noexcept;
+
+[[using __gnu__: __returns_nonnull__, __const__]] _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI memory_resource*
+null_memory_resource() noexcept;
+
+} // namespace pmr
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___MEMORY_RESOURCE_MEMORY_RESOURCE_H
diff --git a/libcxx/include/__cxx03/__memory_resource/monotonic_buffer_resource.h b/libcxx/include/__cxx03/__memory_resource/monotonic_buffer_resource.h
new file mode 100644
index 00000000000000..f45b30fdb38616
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory_resource/monotonic_buffer_resource.h
@@ -0,0 +1,122 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RESOURCE_MONOTONIC_BUFFER_RESOURCE_H
+#define _LIBCPP___MEMORY_RESOURCE_MONOTONIC_BUFFER_RESOURCE_H
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory_resource/memory_resource.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace pmr {
+
+// [mem.res.monotonic.buffer]
+
+class _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI monotonic_buffer_resource : public memory_resource {
+ static const size_t __default_buffer_capacity = 1024;
+ static const size_t __default_buffer_alignment = 16;
+
+ struct __chunk_footer {
+ __chunk_footer* __next_;
+ char* __start_;
+ char* __cur_;
+ size_t __align_;
+ _LIBCPP_HIDE_FROM_ABI size_t __allocation_size() {
+ return (reinterpret_cast<char*>(this) - __start_) + sizeof(*this);
+ }
+ void* __try_allocate_from_chunk(size_t, size_t);
+ };
+
+ struct __initial_descriptor {
+ char* __start_;
+ char* __cur_;
+ union {
+ char* __end_;
+ size_t __size_;
+ };
+ void* __try_allocate_from_chunk(size_t, size_t);
+ };
+
+public:
+ _LIBCPP_HIDE_FROM_ABI monotonic_buffer_resource()
+ : monotonic_buffer_resource(nullptr, __default_buffer_capacity, get_default_resource()) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit monotonic_buffer_resource(size_t __initial_size)
+ : monotonic_buffer_resource(nullptr, __initial_size, get_default_resource()) {}
+
+ _LIBCPP_HIDE_FROM_ABI monotonic_buffer_resource(void* __buffer, size_t __buffer_size)
+ : monotonic_buffer_resource(__buffer, __buffer_size, get_default_resource()) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit monotonic_buffer_resource(memory_resource* __upstream)
+ : monotonic_buffer_resource(nullptr, __default_buffer_capacity, __upstream) {}
+
+ _LIBCPP_HIDE_FROM_ABI monotonic_buffer_resource(size_t __initial_size, memory_resource* __upstream)
+ : monotonic_buffer_resource(nullptr, __initial_size, __upstream) {}
+
+ _LIBCPP_HIDE_FROM_ABI monotonic_buffer_resource(void* __buffer, size_t __buffer_size, memory_resource* __upstream)
+ : __res_(__upstream) {
+ __initial_.__start_ = static_cast<char*>(__buffer);
+ if (__buffer != nullptr) {
+ __initial_.__cur_ = static_cast<char*>(__buffer) + __buffer_size;
+ __initial_.__end_ = static_cast<char*>(__buffer) + __buffer_size;
+ } else {
+ __initial_.__cur_ = nullptr;
+ __initial_.__size_ = __buffer_size;
+ }
+ __chunks_ = nullptr;
+ }
+
+ monotonic_buffer_resource(const monotonic_buffer_resource&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~monotonic_buffer_resource() override { release(); }
+
+ monotonic_buffer_resource& operator=(const monotonic_buffer_resource&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI void release() {
+ if (__initial_.__start_ != nullptr)
+ __initial_.__cur_ = __initial_.__end_;
+ while (__chunks_ != nullptr) {
+ __chunk_footer* __next = __chunks_->__next_;
+ __res_->deallocate(__chunks_->__start_, __chunks_->__allocation_size(), __chunks_->__align_);
+ __chunks_ = __next;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI memory_resource* upstream_resource() const { return __res_; }
+
+protected:
+ void* do_allocate(size_t __bytes, size_t __alignment) override; // key function
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void do_deallocate(void*, size_t, size_t) override {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL bool do_is_equal(const memory_resource& __other) const _NOEXCEPT override {
+ return this == std::addressof(__other);
+ }
+
+private:
+ __initial_descriptor __initial_;
+ __chunk_footer* __chunks_;
+ memory_resource* __res_;
+};
+
+} // namespace pmr
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___MEMORY_RESOURCE_MONOTONIC_BUFFER_RESOURCE_H
diff --git a/libcxx/include/__cxx03/__memory_resource/polymorphic_allocator.h b/libcxx/include/__cxx03/__memory_resource/polymorphic_allocator.h
new file mode 100644
index 00000000000000..a71096d3e47847
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory_resource/polymorphic_allocator.h
@@ -0,0 +1,231 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RESOURCE_POLYMORPHIC_ALLOCATOR_H
+#define _LIBCPP___MEMORY_RESOURCE_POLYMORPHIC_ALLOCATOR_H
+
+#include <__assert>
+#include <__config>
+#include <__fwd/pair.h>
+#include <__memory_resource/memory_resource.h>
+#include <__utility/exception_guard.h>
+#include <cstddef>
+#include <limits>
+#include <new>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace pmr {
+
+// [mem.poly.allocator.class]
+
+template <class _ValueType
+# if _LIBCPP_STD_VER >= 20
+ = byte
+# endif
+ >
+class _LIBCPP_AVAILABILITY_PMR _LIBCPP_TEMPLATE_VIS polymorphic_allocator {
+
+public:
+ using value_type = _ValueType;
+
+ // [mem.poly.allocator.ctor]
+
+ _LIBCPP_HIDE_FROM_ABI polymorphic_allocator() noexcept : __res_(std::pmr::get_default_resource()) {}
+
+ _LIBCPP_HIDE_FROM_ABI polymorphic_allocator(memory_resource* __r) noexcept : __res_(__r) {}
+
+ _LIBCPP_HIDE_FROM_ABI polymorphic_allocator(const polymorphic_allocator&) = default;
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI polymorphic_allocator(const polymorphic_allocator<_Tp>& __other) noexcept
+ : __res_(__other.resource()) {}
+
+ polymorphic_allocator& operator=(const polymorphic_allocator&) = delete;
+
+ // [mem.poly.allocator.mem]
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI _ValueType* allocate(size_t __n) {
+ if (__n > __max_size()) {
+ __throw_bad_array_new_length();
+ }
+ return static_cast<_ValueType*>(__res_->allocate(__n * sizeof(_ValueType), alignof(_ValueType)));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void deallocate(_ValueType* __p, size_t __n) {
+ _LIBCPP_ASSERT_VALID_DEALLOCATION(
+ __n <= __max_size(),
+ "deallocate() called for a size which exceeds max_size(), leading to a memory leak "
+ "(the argument will overflow and result in too few objects being deleted)");
+ __res_->deallocate(__p, __n * sizeof(_ValueType), alignof(_ValueType));
+ }
+
+# if _LIBCPP_STD_VER >= 20
+
+ [[nodiscard]] [[using __gnu__: __alloc_size__(2), __alloc_align__(3)]] _LIBCPP_HIDE_FROM_ABI void*
+ allocate_bytes(size_t __nbytes, size_t __alignment = alignof(max_align_t)) {
+ return __res_->allocate(__nbytes, __alignment);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void deallocate_bytes(void* __ptr, size_t __nbytes, size_t __alignment = alignof(max_align_t)) {
+ __res_->deallocate(__ptr, __nbytes, __alignment);
+ }
+
+ template <class _Type>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI _Type* allocate_object(size_t __n = 1) {
+ if (numeric_limits<size_t>::max() / sizeof(_Type) < __n)
+ std::__throw_bad_array_new_length();
+ return static_cast<_Type*>(allocate_bytes(__n * sizeof(_Type), alignof(_Type)));
+ }
+
+ template <class _Type>
+ _LIBCPP_HIDE_FROM_ABI void deallocate_object(_Type* __ptr, size_t __n = 1) {
+ deallocate_bytes(__ptr, __n * sizeof(_Type), alignof(_Type));
+ }
+
+ template <class _Type, class... _CtorArgs>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI _Type* new_object(_CtorArgs&&... __ctor_args) {
+ _Type* __ptr = allocate_object<_Type>();
+ auto __guard = std::__make_exception_guard([&] { deallocate_object(__ptr); });
+ construct(__ptr, std::forward<_CtorArgs>(__ctor_args)...);
+ __guard.__complete();
+ return __ptr;
+ }
+
+ template <class _Type>
+ _LIBCPP_HIDE_FROM_ABI void delete_object(_Type* __ptr) {
+ destroy(__ptr);
+ deallocate_object(__ptr);
+ }
+
+# endif // _LIBCPP_STD_VER >= 20
+
+ template <class _Tp, class... _Ts>
+ _LIBCPP_HIDE_FROM_ABI void construct(_Tp* __p, _Ts&&... __args) {
+ std::__user_alloc_construct_impl(
+ typename __uses_alloc_ctor<_Tp, polymorphic_allocator&, _Ts...>::type(),
+ __p,
+ *this,
+ std::forward<_Ts>(__args)...);
+ }
+
+ template <class _T1, class _T2, class... _Args1, class... _Args2>
+ _LIBCPP_HIDE_FROM_ABI void
+ construct(pair<_T1, _T2>* __p, piecewise_construct_t, tuple<_Args1...> __x, tuple<_Args2...> __y) {
+ ::new ((void*)__p) pair<_T1, _T2>(
+ piecewise_construct,
+ __transform_tuple(typename __uses_alloc_ctor< _T1, polymorphic_allocator&, _Args1... >::type(),
+ std::move(__x),
+ typename __make_tuple_indices<sizeof...(_Args1)>::type{}),
+ __transform_tuple(typename __uses_alloc_ctor< _T2, polymorphic_allocator&, _Args2... >::type(),
+ std::move(__y),
+ typename __make_tuple_indices<sizeof...(_Args2)>::type{}));
+ }
+
+ template <class _T1, class _T2>
+ _LIBCPP_HIDE_FROM_ABI void construct(pair<_T1, _T2>* __p) {
+ construct(__p, piecewise_construct, tuple<>(), tuple<>());
+ }
+
+ template <class _T1, class _T2, class _Up, class _Vp>
+ _LIBCPP_HIDE_FROM_ABI void construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v) {
+ construct(__p,
+ piecewise_construct,
+ std::forward_as_tuple(std::forward<_Up>(__u)),
+ std::forward_as_tuple(std::forward<_Vp>(__v)));
+ }
+
+ template <class _T1, class _T2, class _U1, class _U2>
+ _LIBCPP_HIDE_FROM_ABI void construct(pair<_T1, _T2>* __p, const pair<_U1, _U2>& __pr) {
+ construct(__p, piecewise_construct, std::forward_as_tuple(__pr.first), std::forward_as_tuple(__pr.second));
+ }
+
+ template <class _T1, class _T2, class _U1, class _U2>
+ _LIBCPP_HIDE_FROM_ABI void construct(pair<_T1, _T2>* __p, pair<_U1, _U2>&& __pr) {
+ construct(__p,
+ piecewise_construct,
+ std::forward_as_tuple(std::forward<_U1>(__pr.first)),
+ std::forward_as_tuple(std::forward<_U2>(__pr.second)));
+ }
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI void destroy(_Tp* __p) {
+ __p->~_Tp();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI polymorphic_allocator select_on_container_copy_construction() const noexcept {
+ return polymorphic_allocator();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI memory_resource* resource() const noexcept { return __res_; }
+
+private:
+ template <class... _Args, size_t... _Is>
+ _LIBCPP_HIDE_FROM_ABI tuple<_Args&&...>
+ __transform_tuple(integral_constant<int, 0>, tuple<_Args...>&& __t, __tuple_indices<_Is...>) {
+ return std::forward_as_tuple(std::get<_Is>(std::move(__t))...);
+ }
+
+ template <class... _Args, size_t... _Is>
+ _LIBCPP_HIDE_FROM_ABI tuple<allocator_arg_t const&, polymorphic_allocator&, _Args&&...>
+ __transform_tuple(integral_constant<int, 1>, tuple<_Args...>&& __t, __tuple_indices<_Is...>) {
+ using _Tup = tuple<allocator_arg_t const&, polymorphic_allocator&, _Args&&...>;
+ return _Tup(allocator_arg, *this, std::get<_Is>(std::move(__t))...);
+ }
+
+ template <class... _Args, size_t... _Is>
+ _LIBCPP_HIDE_FROM_ABI tuple<_Args&&..., polymorphic_allocator&>
+ __transform_tuple(integral_constant<int, 2>, tuple<_Args...>&& __t, __tuple_indices<_Is...>) {
+ using _Tup = tuple<_Args&&..., polymorphic_allocator&>;
+ return _Tup(std::get<_Is>(std::move(__t))..., *this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_t __max_size() const noexcept {
+ return numeric_limits<size_t>::max() / sizeof(value_type);
+ }
+
+ memory_resource* __res_;
+};
+
+// [mem.poly.allocator.eq]
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const polymorphic_allocator<_Tp>& __lhs, const polymorphic_allocator<_Up>& __rhs) noexcept {
+ return *__lhs.resource() == *__rhs.resource();
+}
+
+# if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const polymorphic_allocator<_Tp>& __lhs, const polymorphic_allocator<_Up>& __rhs) noexcept {
+ return !(__lhs == __rhs);
+}
+
+# endif
+
+} // namespace pmr
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MEMORY_RESOURCE_POLYMORPHIC_ALLOCATOR_H
diff --git a/libcxx/include/__cxx03/__memory_resource/pool_options.h b/libcxx/include/__cxx03/__memory_resource/pool_options.h
new file mode 100644
index 00000000000000..442959836c7ef3
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory_resource/pool_options.h
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RESOURCE_POOL_OPTIONS_H
+#define _LIBCPP___MEMORY_RESOURCE_POOL_OPTIONS_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace pmr {
+
+// [mem.res.pool.options]
+
+struct _LIBCPP_EXPORTED_FROM_ABI pool_options {
+ size_t max_blocks_per_chunk = 0;
+ size_t largest_required_pool_block = 0;
+};
+
+} // namespace pmr
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___MEMORY_RESOURCE_POOL_OPTIONS_H
diff --git a/libcxx/include/__cxx03/__memory_resource/synchronized_pool_resource.h b/libcxx/include/__cxx03/__memory_resource/synchronized_pool_resource.h
new file mode 100644
index 00000000000000..50a673c2861d10
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory_resource/synchronized_pool_resource.h
@@ -0,0 +1,92 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RESOURCE_SYNCHRONIZED_POOL_RESOURCE_H
+#define _LIBCPP___MEMORY_RESOURCE_SYNCHRONIZED_POOL_RESOURCE_H
+
+#include <__config>
+#include <__memory_resource/memory_resource.h>
+#include <__memory_resource/pool_options.h>
+#include <__memory_resource/unsynchronized_pool_resource.h>
+#include <cstddef>
+#include <mutex>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace pmr {
+
+// [mem.res.pool.overview]
+
+class _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI synchronized_pool_resource : public memory_resource {
+public:
+ _LIBCPP_HIDE_FROM_ABI synchronized_pool_resource(const pool_options& __opts, memory_resource* __upstream)
+ : __unsync_(__opts, __upstream) {}
+
+ _LIBCPP_HIDE_FROM_ABI synchronized_pool_resource()
+ : synchronized_pool_resource(pool_options(), get_default_resource()) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit synchronized_pool_resource(memory_resource* __upstream)
+ : synchronized_pool_resource(pool_options(), __upstream) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit synchronized_pool_resource(const pool_options& __opts)
+ : synchronized_pool_resource(__opts, get_default_resource()) {}
+
+ synchronized_pool_resource(const synchronized_pool_resource&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~synchronized_pool_resource() override = default;
+
+ synchronized_pool_resource& operator=(const synchronized_pool_resource&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI void release() {
+# if !defined(_LIBCPP_HAS_NO_THREADS)
+ unique_lock<mutex> __lk(__mut_);
+# endif
+ __unsync_.release();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI memory_resource* upstream_resource() const { return __unsync_.upstream_resource(); }
+
+ _LIBCPP_HIDE_FROM_ABI pool_options options() const { return __unsync_.options(); }
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void* do_allocate(size_t __bytes, size_t __align) override {
+# if !defined(_LIBCPP_HAS_NO_THREADS)
+ unique_lock<mutex> __lk(__mut_);
+# endif
+ return __unsync_.allocate(__bytes, __align);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void do_deallocate(void* __p, size_t __bytes, size_t __align) override {
+# if !defined(_LIBCPP_HAS_NO_THREADS)
+ unique_lock<mutex> __lk(__mut_);
+# endif
+ return __unsync_.deallocate(__p, __bytes, __align);
+ }
+
+ bool do_is_equal(const memory_resource& __other) const noexcept override; // key function
+
+private:
+# if !defined(_LIBCPP_HAS_NO_THREADS)
+ mutex __mut_;
+# endif
+ unsynchronized_pool_resource __unsync_;
+};
+
+} // namespace pmr
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___MEMORY_RESOURCE_SYNCHRONIZED_POOL_RESOURCE_H
diff --git a/libcxx/include/__cxx03/__memory_resource/unsynchronized_pool_resource.h b/libcxx/include/__cxx03/__memory_resource/unsynchronized_pool_resource.h
new file mode 100644
index 00000000000000..783db84262af72
--- /dev/null
+++ b/libcxx/include/__cxx03/__memory_resource/unsynchronized_pool_resource.h
@@ -0,0 +1,106 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_RESOURCE_UNSYNCHRONIZED_POOL_RESOURCE_H
+#define _LIBCPP___MEMORY_RESOURCE_UNSYNCHRONIZED_POOL_RESOURCE_H
+
+#include <__config>
+#include <__memory_resource/memory_resource.h>
+#include <__memory_resource/pool_options.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace pmr {
+
+// [mem.res.pool.overview]
+
+class _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI unsynchronized_pool_resource : public memory_resource {
+ class __fixed_pool;
+
+ class __adhoc_pool {
+ struct __chunk_footer;
+ __chunk_footer* __first_;
+
+ public:
+ _LIBCPP_HIDE_FROM_ABI explicit __adhoc_pool() : __first_(nullptr) {}
+
+ void __release_ptr(memory_resource* __upstream);
+ void* __do_allocate(memory_resource* __upstream, size_t __bytes, size_t __align);
+ void __do_deallocate(memory_resource* __upstream, void* __p, size_t __bytes, size_t __align);
+ };
+
+ static const size_t __min_blocks_per_chunk = 16;
+ static const size_t __min_bytes_per_chunk = 1024;
+ static const size_t __max_blocks_per_chunk = (size_t(1) << 20);
+ static const size_t __max_bytes_per_chunk = (size_t(1) << 30);
+
+ static const int __log2_smallest_block_size = 3;
+ static const size_t __smallest_block_size = 8;
+ static const size_t __default_largest_block_size = (size_t(1) << 20);
+ static const size_t __max_largest_block_size = (size_t(1) << 30);
+
+ size_t __pool_block_size(int __i) const;
+ int __log2_pool_block_size(int __i) const;
+ int __pool_index(size_t __bytes, size_t __align) const;
+
+public:
+ unsynchronized_pool_resource(const pool_options& __opts, memory_resource* __upstream);
+
+ _LIBCPP_HIDE_FROM_ABI unsynchronized_pool_resource()
+ : unsynchronized_pool_resource(pool_options(), get_default_resource()) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit unsynchronized_pool_resource(memory_resource* __upstream)
+ : unsynchronized_pool_resource(pool_options(), __upstream) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit unsynchronized_pool_resource(const pool_options& __opts)
+ : unsynchronized_pool_resource(__opts, get_default_resource()) {}
+
+ unsynchronized_pool_resource(const unsynchronized_pool_resource&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~unsynchronized_pool_resource() override { release(); }
+
+ unsynchronized_pool_resource& operator=(const unsynchronized_pool_resource&) = delete;
+
+ void release();
+
+ _LIBCPP_HIDE_FROM_ABI memory_resource* upstream_resource() const { return __res_; }
+
+ [[__gnu__::__pure__]] pool_options options() const;
+
+protected:
+ void* do_allocate(size_t __bytes, size_t __align) override; // key function
+
+ void do_deallocate(void* __p, size_t __bytes, size_t __align) override;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL bool do_is_equal(const memory_resource& __other) const _NOEXCEPT override {
+ return &__other == this;
+ }
+
+private:
+ memory_resource* __res_;
+ __adhoc_pool __adhoc_pool_;
+ __fixed_pool* __fixed_pools_;
+ int __num_fixed_pools_;
+ uint32_t __options_max_blocks_per_chunk_;
+};
+
+} // namespace pmr
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___MEMORY_RESOURCE_UNSYNCHRONIZED_POOL_RESOURCE_H
diff --git a/libcxx/include/__cxx03/__mutex/lock_guard.h b/libcxx/include/__cxx03/__mutex/lock_guard.h
new file mode 100644
index 00000000000000..ef56896be9f68c
--- /dev/null
+++ b/libcxx/include/__cxx03/__mutex/lock_guard.h
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MUTEX_LOCK_GUARD_H
+#define _LIBCPP___MUTEX_LOCK_GUARD_H
+
+#include <__config>
+#include <__mutex/tag_types.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Mutex>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_THREAD_SAFETY_ANNOTATION(scoped_lockable) lock_guard {
+public:
+ typedef _Mutex mutex_type;
+
+private:
+ mutex_type& __m_;
+
+public:
+ _LIBCPP_NODISCARD
+ _LIBCPP_HIDE_FROM_ABI explicit lock_guard(mutex_type& __m) _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability(__m))
+ : __m_(__m) {
+ __m_.lock();
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI lock_guard(mutex_type& __m, adopt_lock_t)
+ _LIBCPP_THREAD_SAFETY_ANNOTATION(requires_capability(__m))
+ : __m_(__m) {}
+ _LIBCPP_HIDE_FROM_ABI ~lock_guard() _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability()) { __m_.unlock(); }
+
+ lock_guard(lock_guard const&) = delete;
+ lock_guard& operator=(lock_guard const&) = delete;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(lock_guard);
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MUTEX_LOCK_GUARD_H
diff --git a/libcxx/include/__cxx03/__mutex/mutex.h b/libcxx/include/__cxx03/__mutex/mutex.h
new file mode 100644
index 00000000000000..1ed01547126f48
--- /dev/null
+++ b/libcxx/include/__cxx03/__mutex/mutex.h
@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MUTEX_MUTEX_H
+#define _LIBCPP___MUTEX_MUTEX_H
+
+#include <__config>
+#include <__thread/support.h>
+#include <__type_traits/is_nothrow_constructible.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_THREAD_SAFETY_ANNOTATION(capability("mutex")) mutex {
+ __libcpp_mutex_t __m_ = _LIBCPP_MUTEX_INITIALIZER;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR mutex() = default;
+
+ mutex(const mutex&) = delete;
+ mutex& operator=(const mutex&) = delete;
+
+# if defined(_LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION)
+ _LIBCPP_HIDE_FROM_ABI ~mutex() = default;
+# else
+ ~mutex() _NOEXCEPT;
+# endif
+
+ void lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability());
+ bool try_lock() _NOEXCEPT _LIBCPP_THREAD_SAFETY_ANNOTATION(try_acquire_capability(true));
+ void unlock() _NOEXCEPT _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability());
+
+ typedef __libcpp_mutex_t* native_handle_type;
+ _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() { return &__m_; }
+};
+
+static_assert(is_nothrow_default_constructible<mutex>::value, "the default constructor for std::mutex must be nothrow");
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_HAS_NO_THREADS
+
+#endif // _LIBCPP___MUTEX_MUTEX_H
diff --git a/libcxx/include/__cxx03/__mutex/once_flag.h b/libcxx/include/__cxx03/__mutex/once_flag.h
new file mode 100644
index 00000000000000..9d7baecbc70859
--- /dev/null
+++ b/libcxx/include/__cxx03/__mutex/once_flag.h
@@ -0,0 +1,159 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MUTEX_ONCE_FLAG_H
+#define _LIBCPP___MUTEX_ONCE_FLAG_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__memory/shared_ptr.h> // __libcpp_acquire_load
+#include <__tuple/tuple_indices.h>
+#include <__tuple/tuple_size.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <cstdint>
+#ifndef _LIBCPP_CXX03_LANG
+# include <tuple>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct _LIBCPP_TEMPLATE_VIS once_flag;
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Callable, class... _Args>
+_LIBCPP_HIDE_FROM_ABI void call_once(once_flag&, _Callable&&, _Args&&...);
+
+#else // _LIBCPP_CXX03_LANG
+
+template <class _Callable>
+_LIBCPP_HIDE_FROM_ABI void call_once(once_flag&, _Callable&);
+
+template <class _Callable>
+_LIBCPP_HIDE_FROM_ABI void call_once(once_flag&, const _Callable&);
+
+#endif // _LIBCPP_CXX03_LANG
+
+struct _LIBCPP_TEMPLATE_VIS once_flag {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR once_flag() _NOEXCEPT : __state_(_Unset) {}
+ once_flag(const once_flag&) = delete;
+ once_flag& operator=(const once_flag&) = delete;
+
+#if defined(_LIBCPP_ABI_MICROSOFT)
+ typedef uintptr_t _State_type;
+#else
+ typedef unsigned long _State_type;
+#endif
+
+ static const _State_type _Unset = 0;
+ static const _State_type _Pending = 1;
+ static const _State_type _Complete = ~_State_type(0);
+
+private:
+ _State_type __state_;
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Callable, class... _Args>
+ friend void call_once(once_flag&, _Callable&&, _Args&&...);
+#else // _LIBCPP_CXX03_LANG
+ template <class _Callable>
+ friend void call_once(once_flag&, _Callable&);
+
+ template <class _Callable>
+ friend void call_once(once_flag&, const _Callable&);
+#endif // _LIBCPP_CXX03_LANG
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Fp>
+class __call_once_param {
+ _Fp& __f_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __call_once_param(_Fp& __f) : __f_(__f) {}
+
+ _LIBCPP_HIDE_FROM_ABI void operator()() {
+ typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 1>::type _Index;
+ __execute(_Index());
+ }
+
+private:
+ template <size_t... _Indices>
+ _LIBCPP_HIDE_FROM_ABI void __execute(__tuple_indices<_Indices...>) {
+ std::__invoke(std::get<0>(std::move(__f_)), std::get<_Indices>(std::move(__f_))...);
+ }
+};
+
+#else
+
+template <class _Fp>
+class __call_once_param {
+ _Fp& __f_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __call_once_param(_Fp& __f) : __f_(__f) {}
+
+ _LIBCPP_HIDE_FROM_ABI void operator()() { __f_(); }
+};
+
+#endif
+
+template <class _Fp>
+void _LIBCPP_HIDE_FROM_ABI __call_once_proxy(void* __vp) {
+ __call_once_param<_Fp>* __p = static_cast<__call_once_param<_Fp>*>(__vp);
+ (*__p)();
+}
+
+_LIBCPP_EXPORTED_FROM_ABI void __call_once(volatile once_flag::_State_type&, void*, void (*)(void*));
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Callable, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI void call_once(once_flag& __flag, _Callable&& __func, _Args&&... __args) {
+ if (__libcpp_acquire_load(&__flag.__state_) != once_flag::_Complete) {
+ typedef tuple<_Callable&&, _Args&&...> _Gp;
+ _Gp __f(std::forward<_Callable>(__func), std::forward<_Args>(__args)...);
+ __call_once_param<_Gp> __p(__f);
+ std::__call_once(__flag.__state_, &__p, &__call_once_proxy<_Gp>);
+ }
+}
+
+#else // _LIBCPP_CXX03_LANG
+
+template <class _Callable>
+inline _LIBCPP_HIDE_FROM_ABI void call_once(once_flag& __flag, _Callable& __func) {
+ if (__libcpp_acquire_load(&__flag.__state_) != once_flag::_Complete) {
+ __call_once_param<_Callable> __p(__func);
+ std::__call_once(__flag.__state_, &__p, &__call_once_proxy<_Callable>);
+ }
+}
+
+template <class _Callable>
+inline _LIBCPP_HIDE_FROM_ABI void call_once(once_flag& __flag, const _Callable& __func) {
+ if (__libcpp_acquire_load(&__flag.__state_) != once_flag::_Complete) {
+ __call_once_param<const _Callable> __p(__func);
+ std::__call_once(__flag.__state_, &__p, &__call_once_proxy<const _Callable>);
+ }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MUTEX_ONCE_FLAG_H
diff --git a/libcxx/include/__cxx03/__mutex/tag_types.h b/libcxx/include/__cxx03/__mutex/tag_types.h
new file mode 100644
index 00000000000000..2b2dd58ee4e80b
--- /dev/null
+++ b/libcxx/include/__cxx03/__mutex/tag_types.h
@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MUTEX_TAG_TYPES_H
+#define _LIBCPP___MUTEX_TAG_TYPES_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct _LIBCPP_EXPORTED_FROM_ABI defer_lock_t {
+ explicit defer_lock_t() = default;
+};
+
+struct _LIBCPP_EXPORTED_FROM_ABI try_to_lock_t {
+ explicit try_to_lock_t() = default;
+};
+
+struct _LIBCPP_EXPORTED_FROM_ABI adopt_lock_t {
+ explicit adopt_lock_t() = default;
+};
+
+#if _LIBCPP_STD_VER >= 17
+inline constexpr defer_lock_t defer_lock = defer_lock_t();
+inline constexpr try_to_lock_t try_to_lock = try_to_lock_t();
+inline constexpr adopt_lock_t adopt_lock = adopt_lock_t();
+#elif !defined(_LIBCPP_CXX03_LANG)
+constexpr defer_lock_t defer_lock = defer_lock_t();
+constexpr try_to_lock_t try_to_lock = try_to_lock_t();
+constexpr adopt_lock_t adopt_lock = adopt_lock_t();
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MUTEX_TAG_TYPES_H
diff --git a/libcxx/include/__cxx03/__mutex/unique_lock.h b/libcxx/include/__cxx03/__mutex/unique_lock.h
new file mode 100644
index 00000000000000..4a616ba51ee1cf
--- /dev/null
+++ b/libcxx/include/__cxx03/__mutex/unique_lock.h
@@ -0,0 +1,177 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MUTEX_UNIQUE_LOCK_H
+#define _LIBCPP___MUTEX_UNIQUE_LOCK_H
+
+#include <__chrono/duration.h>
+#include <__chrono/time_point.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__mutex/tag_types.h>
+#include <__system_error/system_error.h>
+#include <__utility/swap.h>
+#include <cerrno>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Mutex>
+class _LIBCPP_TEMPLATE_VIS unique_lock {
+public:
+ typedef _Mutex mutex_type;
+
+private:
+ mutex_type* __m_;
+ bool __owns_;
+
+public:
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI unique_lock() _NOEXCEPT : __m_(nullptr), __owns_(false) {}
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI explicit unique_lock(mutex_type& __m)
+ : __m_(std::addressof(__m)), __owns_(true) {
+ __m_->lock();
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, defer_lock_t) _NOEXCEPT
+ : __m_(std::addressof(__m)),
+ __owns_(false) {}
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, try_to_lock_t)
+ : __m_(std::addressof(__m)), __owns_(__m.try_lock()) {}
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, adopt_lock_t)
+ : __m_(std::addressof(__m)), __owns_(true) {}
+
+ template <class _Clock, class _Duration>
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, const chrono::time_point<_Clock, _Duration>& __t)
+ : __m_(std::addressof(__m)), __owns_(__m.try_lock_until(__t)) {}
+
+ template <class _Rep, class _Period>
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, const chrono::duration<_Rep, _Period>& __d)
+ : __m_(std::addressof(__m)), __owns_(__m.try_lock_for(__d)) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~unique_lock() {
+ if (__owns_)
+ __m_->unlock();
+ }
+
+ unique_lock(unique_lock const&) = delete;
+ unique_lock& operator=(unique_lock const&) = delete;
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI unique_lock(unique_lock&& __u) _NOEXCEPT
+ : __m_(__u.__m_),
+ __owns_(__u.__owns_) {
+ __u.__m_ = nullptr;
+ __u.__owns_ = false;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI unique_lock& operator=(unique_lock&& __u) _NOEXCEPT {
+ if (__owns_)
+ __m_->unlock();
+
+ __m_ = __u.__m_;
+ __owns_ = __u.__owns_;
+ __u.__m_ = nullptr;
+ __u.__owns_ = false;
+ return *this;
+ }
+
+ void lock();
+ bool try_lock();
+
+ template <class _Rep, class _Period>
+ bool try_lock_for(const chrono::duration<_Rep, _Period>& __d);
+
+ template <class _Clock, class _Duration>
+ bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t);
+
+ void unlock();
+
+ _LIBCPP_HIDE_FROM_ABI void swap(unique_lock& __u) _NOEXCEPT {
+ std::swap(__m_, __u.__m_);
+ std::swap(__owns_, __u.__owns_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI mutex_type* release() _NOEXCEPT {
+ mutex_type* __m = __m_;
+ __m_ = nullptr;
+ __owns_ = false;
+ return __m;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool owns_lock() const _NOEXCEPT { return __owns_; }
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return __owns_; }
+ _LIBCPP_HIDE_FROM_ABI mutex_type* mutex() const _NOEXCEPT { return __m_; }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(unique_lock);
+
+template <class _Mutex>
+void unique_lock<_Mutex>::lock() {
+ if (__m_ == nullptr)
+ __throw_system_error(EPERM, "unique_lock::lock: references null mutex");
+ if (__owns_)
+ __throw_system_error(EDEADLK, "unique_lock::lock: already locked");
+ __m_->lock();
+ __owns_ = true;
+}
+
+template <class _Mutex>
+bool unique_lock<_Mutex>::try_lock() {
+ if (__m_ == nullptr)
+ __throw_system_error(EPERM, "unique_lock::try_lock: references null mutex");
+ if (__owns_)
+ __throw_system_error(EDEADLK, "unique_lock::try_lock: already locked");
+ __owns_ = __m_->try_lock();
+ return __owns_;
+}
+
+template <class _Mutex>
+template <class _Rep, class _Period>
+bool unique_lock<_Mutex>::try_lock_for(const chrono::duration<_Rep, _Period>& __d) {
+ if (__m_ == nullptr)
+ __throw_system_error(EPERM, "unique_lock::try_lock_for: references null mutex");
+ if (__owns_)
+ __throw_system_error(EDEADLK, "unique_lock::try_lock_for: already locked");
+ __owns_ = __m_->try_lock_for(__d);
+ return __owns_;
+}
+
+template <class _Mutex>
+template <class _Clock, class _Duration>
+bool unique_lock<_Mutex>::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) {
+ if (__m_ == nullptr)
+ __throw_system_error(EPERM, "unique_lock::try_lock_until: references null mutex");
+ if (__owns_)
+ __throw_system_error(EDEADLK, "unique_lock::try_lock_until: already locked");
+ __owns_ = __m_->try_lock_until(__t);
+ return __owns_;
+}
+
+template <class _Mutex>
+void unique_lock<_Mutex>::unlock() {
+ if (!__owns_)
+ __throw_system_error(EPERM, "unique_lock::unlock: not locked");
+ __m_->unlock();
+ __owns_ = false;
+}
+
+template <class _Mutex>
+inline _LIBCPP_HIDE_FROM_ABI void swap(unique_lock<_Mutex>& __x, unique_lock<_Mutex>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_HAS_NO_THREADS
+
+#endif // _LIBCPP___MUTEX_UNIQUE_LOCK_H
diff --git a/libcxx/include/__cxx03/__node_handle b/libcxx/include/__cxx03/__node_handle
new file mode 100644
index 00000000000000..d0b35bfd193409
--- /dev/null
+++ b/libcxx/include/__cxx03/__node_handle
@@ -0,0 +1,209 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NODE_HANDLE
+#define _LIBCPP___NODE_HANDLE
+
+/*
+
+template<unspecified>
+class node-handle {
+public:
+ using value_type = see below; // not present for map containers
+ using key_type = see below; // not present for set containers
+ using mapped_type = see below; // not present for set containers
+ using allocator_type = see below;
+
+private:
+ using container_node_type = unspecified; // exposition only
+ using ator_traits = allocator_traits<allocator_type>; // exposition only
+
+ typename ator_traits::template
+ rebind_traits<container_node_type>::pointer ptr_; // exposition only
+ optional<allocator_type> alloc_; // exposition only
+
+public:
+ // [container.node.cons], constructors, copy, and assignment
+ constexpr node-handle() noexcept : ptr_(), alloc_() {}
+ node-handle(node-handle&&) noexcept;
+ node-handle& operator=(node-handle&&);
+
+ // [container.node.dtor], destructor
+ ~node-handle();
+
+ // [container.node.observers], observers
+ value_type& value() const; // not present for map containers
+ key_type& key() const; // not present for set containers
+ mapped_type& mapped() const; // not present for set containers
+
+ allocator_type get_allocator() const;
+ explicit operator bool() const noexcept;
+ [[nodiscard]] bool empty() const noexcept; // nodiscard since C++20
+
+ // [container.node.modifiers], modifiers
+ void swap(node-handle&)
+ noexcept(ator_traits::propagate_on_container_swap::value ||
+ ator_traits::is_always_equal::value);
+
+ friend void swap(node-handle& x, node-handle& y) noexcept(noexcept(x.swap(y))) {
+ x.swap(y);
+ }
+};
+
+*/
+
+#include <__assert>
+#include <__config>
+#include <__memory/allocator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+// Specialized in __tree & __hash_table for their _NodeType.
+template <class _NodeType, class _Alloc>
+struct __generic_container_node_destructor;
+
+template <class _NodeType, class _Alloc, template <class, class> class _MapOrSetSpecifics>
+class _LIBCPP_TEMPLATE_VIS __basic_node_handle
+ : public _MapOrSetSpecifics< _NodeType, __basic_node_handle<_NodeType, _Alloc, _MapOrSetSpecifics>> {
+ template <class _Tp, class _Compare, class _Allocator>
+ friend class __tree;
+ template <class _Tp, class _Hash, class _Equal, class _Allocator>
+ friend class __hash_table;
+ friend struct _MapOrSetSpecifics< _NodeType, __basic_node_handle<_NodeType, _Alloc, _MapOrSetSpecifics>>;
+
+ typedef allocator_traits<_Alloc> __alloc_traits;
+ typedef __rebind_pointer_t<typename __alloc_traits::void_pointer, _NodeType> __node_pointer_type;
+
+public:
+ typedef _Alloc allocator_type;
+
+private:
+ __node_pointer_type __ptr_ = nullptr;
+ optional<allocator_type> __alloc_;
+
+ _LIBCPP_HIDE_FROM_ABI void __release_ptr() {
+ __ptr_ = nullptr;
+ __alloc_ = std::nullopt;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __destroy_node_pointer() {
+ if (__ptr_ != nullptr) {
+ typedef typename __allocator_traits_rebind< allocator_type, _NodeType>::type __node_alloc_type;
+ __node_alloc_type __alloc(*__alloc_);
+ __generic_container_node_destructor<_NodeType, __node_alloc_type>(__alloc, true)(__ptr_);
+ __ptr_ = nullptr;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __basic_node_handle(__node_pointer_type __ptr, allocator_type const& __alloc)
+ : __ptr_(__ptr), __alloc_(__alloc) {}
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __basic_node_handle() = default;
+
+ _LIBCPP_HIDE_FROM_ABI __basic_node_handle(__basic_node_handle&& __other) noexcept
+ : __ptr_(__other.__ptr_), __alloc_(std::move(__other.__alloc_)) {
+ __other.__ptr_ = nullptr;
+ __other.__alloc_ = std::nullopt;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __basic_node_handle& operator=(__basic_node_handle&& __other) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __alloc_ == std::nullopt || __alloc_traits::propagate_on_container_move_assignment::value ||
+ __alloc_ == __other.__alloc_,
+ "node_type with incompatible allocator passed to "
+ "node_type::operator=(node_type&&)");
+
+ __destroy_node_pointer();
+ __ptr_ = __other.__ptr_;
+
+ if (__alloc_traits::propagate_on_container_move_assignment::value || __alloc_ == std::nullopt)
+ __alloc_ = std::move(__other.__alloc_);
+
+ __other.__ptr_ = nullptr;
+ __other.__alloc_ = std::nullopt;
+
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const { return *__alloc_; }
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const { return __ptr_ != nullptr; }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool empty() const { return __ptr_ == nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(__basic_node_handle& __other) noexcept(
+ __alloc_traits::propagate_on_container_swap::value || __alloc_traits::is_always_equal::value) {
+ using std::swap;
+ swap(__ptr_, __other.__ptr_);
+ if (__alloc_traits::propagate_on_container_swap::value || __alloc_ == std::nullopt ||
+ __other.__alloc_ == std::nullopt)
+ swap(__alloc_, __other.__alloc_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend void
+ swap(__basic_node_handle& __a, __basic_node_handle& __b) noexcept(noexcept(__a.swap(__b))) {
+ __a.swap(__b);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~__basic_node_handle() { __destroy_node_pointer(); }
+};
+
+template <class _NodeType, class _Derived>
+struct __set_node_handle_specifics {
+ typedef typename _NodeType::__node_value_type value_type;
+
+ _LIBCPP_HIDE_FROM_ABI value_type& value() const { return static_cast<_Derived const*>(this)->__ptr_->__get_value(); }
+};
+
+template <class _NodeType, class _Derived>
+struct __map_node_handle_specifics {
+ typedef typename _NodeType::__node_value_type::key_type key_type;
+ typedef typename _NodeType::__node_value_type::mapped_type mapped_type;
+
+ _LIBCPP_HIDE_FROM_ABI key_type& key() const {
+ return static_cast<_Derived const*>(this)->__ptr_->__get_value().__ref().first;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI mapped_type& mapped() const {
+ return static_cast<_Derived const*>(this)->__ptr_->__get_value().__ref().second;
+ }
+};
+
+template <class _NodeType, class _Alloc>
+using __set_node_handle = __basic_node_handle< _NodeType, _Alloc, __set_node_handle_specifics>;
+
+template <class _NodeType, class _Alloc>
+using __map_node_handle = __basic_node_handle< _NodeType, _Alloc, __map_node_handle_specifics>;
+
+template <class _Iterator, class _NodeType>
+struct _LIBCPP_TEMPLATE_VIS __insert_return_type {
+ _Iterator position;
+ bool inserted;
+ _NodeType node;
+};
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NODE_HANDLE
diff --git a/libcxx/include/__cxx03/__numeric/accumulate.h b/libcxx/include/__cxx03/__numeric/accumulate.h
new file mode 100644
index 00000000000000..fedc1c46dfd022
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/accumulate.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_ACCUMULATE_H
+#define _LIBCPP___NUMERIC_ACCUMULATE_H
+
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
+accumulate(_InputIterator __first, _InputIterator __last, _Tp __init) {
+ for (; __first != __last; ++__first)
+#if _LIBCPP_STD_VER >= 20
+ __init = std::move(__init) + *__first;
+#else
+ __init = __init + *__first;
+#endif
+ return __init;
+}
+
+template <class _InputIterator, class _Tp, class _BinaryOperation>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
+accumulate(_InputIterator __first, _InputIterator __last, _Tp __init, _BinaryOperation __binary_op) {
+ for (; __first != __last; ++__first)
+#if _LIBCPP_STD_VER >= 20
+ __init = __binary_op(std::move(__init), *__first);
+#else
+ __init = __binary_op(__init, *__first);
+#endif
+ return __init;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_ACCUMULATE_H
diff --git a/libcxx/include/__cxx03/__numeric/adjacent_difference.h b/libcxx/include/__cxx03/__numeric/adjacent_difference.h
new file mode 100644
index 00000000000000..62b53342d9a414
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/adjacent_difference.h
@@ -0,0 +1,68 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H
+#define _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
+ if (__first != __last) {
+ typename iterator_traits<_InputIterator>::value_type __acc(*__first);
+ *__result = __acc;
+ for (++__first, (void)++__result; __first != __last; ++__first, (void)++__result) {
+ typename iterator_traits<_InputIterator>::value_type __val(*__first);
+#if _LIBCPP_STD_VER >= 20
+ *__result = __val - std::move(__acc);
+#else
+ *__result = __val - __acc;
+#endif
+ __acc = std::move(__val);
+ }
+ }
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator adjacent_difference(
+ _InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOperation __binary_op) {
+ if (__first != __last) {
+ typename iterator_traits<_InputIterator>::value_type __acc(*__first);
+ *__result = __acc;
+ for (++__first, (void)++__result; __first != __last; ++__first, (void)++__result) {
+ typename iterator_traits<_InputIterator>::value_type __val(*__first);
+#if _LIBCPP_STD_VER >= 20
+ *__result = __binary_op(__val, std::move(__acc));
+#else
+ *__result = __binary_op(__val, __acc);
+#endif
+ __acc = std::move(__val);
+ }
+ }
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H
diff --git a/libcxx/include/__cxx03/__numeric/exclusive_scan.h b/libcxx/include/__cxx03/__numeric/exclusive_scan.h
new file mode 100644
index 00000000000000..af85b477dfe68f
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/exclusive_scan.h
@@ -0,0 +1,58 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_EXCLUSIVE_SCAN_H
+#define _LIBCPP___NUMERIC_EXCLUSIVE_SCAN_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+exclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Tp __init, _BinaryOp __b) {
+ if (__first != __last) {
+ _Tp __tmp(__b(__init, *__first));
+ while (true) {
+ *__result = std::move(__init);
+ ++__result;
+ ++__first;
+ if (__first == __last)
+ break;
+ __init = std::move(__tmp);
+ __tmp = __b(__init, *__first);
+ }
+ }
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+exclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Tp __init) {
+ return std::exclusive_scan(__first, __last, __result, __init, std::plus<>());
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_EXCLUSIVE_SCAN_H
diff --git a/libcxx/include/__cxx03/__numeric/gcd_lcm.h b/libcxx/include/__cxx03/__numeric/gcd_lcm.h
new file mode 100644
index 00000000000000..9be6cf8516b131
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/gcd_lcm.h
@@ -0,0 +1,132 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_GCD_LCM_H
+#define _LIBCPP___NUMERIC_GCD_LCM_H
+
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__bit/countr.h>
+#include <__config>
+#include <__type_traits/common_type.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/make_unsigned.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <typename _Result, typename _Source, bool _IsSigned = is_signed<_Source>::value>
+struct __ct_abs;
+
+template <typename _Result, typename _Source>
+struct __ct_abs<_Result, _Source, true> {
+ constexpr _LIBCPP_HIDE_FROM_ABI _Result operator()(_Source __t) const noexcept {
+ if (__t >= 0)
+ return __t;
+ if (__t == numeric_limits<_Source>::min())
+ return -static_cast<_Result>(__t);
+ return -__t;
+ }
+};
+
+template <typename _Result, typename _Source>
+struct __ct_abs<_Result, _Source, false> {
+ constexpr _LIBCPP_HIDE_FROM_ABI _Result operator()(_Source __t) const noexcept { return __t; }
+};
+
+template <class _Tp>
+constexpr _LIBCPP_HIDDEN _Tp __gcd(_Tp __a, _Tp __b) {
+ static_assert(!is_signed<_Tp>::value, "");
+
+ // From: https://lemire.me/blog/2013/12/26/fastest-way-to-compute-the-greatest-common-divisor
+ //
+ // If power of two divides both numbers, we can push it out.
+ // - gcd( 2^x * a, 2^x * b) = 2^x * gcd(a, b)
+ //
+ // If and only if exactly one number is even, we can divide that number by that power.
+ // - if a, b are odd, then gcd(2^x * a, b) = gcd(a, b)
+ //
+ // And standard gcd algorithm where instead of modulo, minus is used.
+
+ if (__a < __b) {
+ _Tp __tmp = __b;
+ __b = __a;
+ __a = __tmp;
+ }
+ if (__b == 0)
+ return __a;
+ __a %= __b; // Make both argument of the same size, and early result in the easy case.
+ if (__a == 0)
+ return __b;
+
+ int __az = std::__countr_zero(__a);
+ int __bz = std::__countr_zero(__b);
+ int __shift = std::min(__az, __bz);
+ __a >>= __az;
+ __b >>= __bz;
+ do {
+ _Tp __diff = __a - __b;
+ if (__a > __b) {
+ __a = __b;
+ __b = __diff;
+ } else {
+ __b = __b - __a;
+ }
+ if (__diff != 0)
+ __b >>= std::__countr_zero(__diff);
+ } while (__b != 0);
+ return __a << __shift;
+}
+
+template <class _Tp, class _Up>
+constexpr _LIBCPP_HIDE_FROM_ABI common_type_t<_Tp, _Up> gcd(_Tp __m, _Up __n) {
+ static_assert(is_integral<_Tp>::value && is_integral<_Up>::value, "Arguments to gcd must be integer types");
+ static_assert(!is_same<__remove_cv_t<_Tp>, bool>::value, "First argument to gcd cannot be bool");
+ static_assert(!is_same<__remove_cv_t<_Up>, bool>::value, "Second argument to gcd cannot be bool");
+ using _Rp = common_type_t<_Tp, _Up>;
+ using _Wp = make_unsigned_t<_Rp>;
+ return static_cast<_Rp>(
+ std::__gcd(static_cast<_Wp>(__ct_abs<_Rp, _Tp>()(__m)), static_cast<_Wp>(__ct_abs<_Rp, _Up>()(__n))));
+}
+
+template <class _Tp, class _Up>
+constexpr _LIBCPP_HIDE_FROM_ABI common_type_t<_Tp, _Up> lcm(_Tp __m, _Up __n) {
+ static_assert(is_integral<_Tp>::value && is_integral<_Up>::value, "Arguments to lcm must be integer types");
+ static_assert(!is_same<__remove_cv_t<_Tp>, bool>::value, "First argument to lcm cannot be bool");
+ static_assert(!is_same<__remove_cv_t<_Up>, bool>::value, "Second argument to lcm cannot be bool");
+ if (__m == 0 || __n == 0)
+ return 0;
+
+ using _Rp = common_type_t<_Tp, _Up>;
+ _Rp __val1 = __ct_abs<_Rp, _Tp>()(__m) / std::gcd(__m, __n);
+ _Rp __val2 = __ct_abs<_Rp, _Up>()(__n);
+ _Rp __res;
+ [[maybe_unused]] bool __overflow = __builtin_mul_overflow(__val1, __val2, &__res);
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(!__overflow, "Overflow in lcm");
+ return __res;
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_GCD_LCM_H
diff --git a/libcxx/include/__cxx03/__numeric/inclusive_scan.h b/libcxx/include/__cxx03/__numeric/inclusive_scan.h
new file mode 100644
index 00000000000000..d714f102d74eff
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/inclusive_scan.h
@@ -0,0 +1,59 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_INCLUSIVE_SCAN_H
+#define _LIBCPP___NUMERIC_INCLUSIVE_SCAN_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+inclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOp __b, _Tp __init) {
+ for (; __first != __last; ++__first, (void)++__result) {
+ __init = __b(__init, *__first);
+ *__result = __init;
+ }
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryOp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+inclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOp __b) {
+ if (__first != __last) {
+ typename iterator_traits<_InputIterator>::value_type __init = *__first;
+ *__result++ = __init;
+ if (++__first != __last)
+ return std::inclusive_scan(__first, __last, __result, __b, __init);
+ }
+
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+inclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
+ return std::inclusive_scan(__first, __last, __result, std::plus<>());
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_INCLUSIVE_SCAN_H
diff --git a/libcxx/include/__cxx03/__numeric/inner_product.h b/libcxx/include/__cxx03/__numeric/inner_product.h
new file mode 100644
index 00000000000000..0deab3d421b771
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/inner_product.h
@@ -0,0 +1,58 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_INNER_PRODUCT_H
+#define _LIBCPP___NUMERIC_INNER_PRODUCT_H
+
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator1, class _InputIterator2, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
+inner_product(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _Tp __init) {
+ for (; __first1 != __last1; ++__first1, (void)++__first2)
+#if _LIBCPP_STD_VER >= 20
+ __init = std::move(__init) + *__first1 * *__first2;
+#else
+ __init = __init + *__first1 * *__first2;
+#endif
+ return __init;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Tp, class _BinaryOperation1, class _BinaryOperation2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp inner_product(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _Tp __init,
+ _BinaryOperation1 __binary_op1,
+ _BinaryOperation2 __binary_op2) {
+ for (; __first1 != __last1; ++__first1, (void)++__first2)
+#if _LIBCPP_STD_VER >= 20
+ __init = __binary_op1(std::move(__init), __binary_op2(*__first1, *__first2));
+#else
+ __init = __binary_op1(__init, __binary_op2(*__first1, *__first2));
+#endif
+ return __init;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_INNER_PRODUCT_H
diff --git a/libcxx/include/__cxx03/__numeric/iota.h b/libcxx/include/__cxx03/__numeric/iota.h
new file mode 100644
index 00000000000000..27bd84e395a3a5
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/iota.h
@@ -0,0 +1,30 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_IOTA_H
+#define _LIBCPP___NUMERIC_IOTA_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+iota(_ForwardIterator __first, _ForwardIterator __last, _Tp __value) {
+ for (; __first != __last; ++__first, (void)++__value)
+ *__first = __value;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_IOTA_H
diff --git a/libcxx/include/__cxx03/__numeric/midpoint.h b/libcxx/include/__cxx03/__numeric/midpoint.h
new file mode 100644
index 00000000000000..5ef30d4ec50f5a
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/midpoint.h
@@ -0,0 +1,88 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_MIDPOINT_H
+#define _LIBCPP___NUMERIC_MIDPOINT_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_null_pointer.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/remove_pointer.h>
+#include <cstddef>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<is_integral_v<_Tp> && !is_same_v<bool, _Tp> && !is_null_pointer_v<_Tp>, _Tp>
+midpoint(_Tp __a, _Tp __b) noexcept _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK {
+ using _Up = make_unsigned_t<_Tp>;
+ constexpr _Up __bitshift = numeric_limits<_Up>::digits - 1;
+
+ _Up __diff = _Up(__b) - _Up(__a);
+ _Up __sign_bit = __b < __a;
+
+ _Up __half_diff = (__diff / 2) + (__sign_bit << __bitshift) + (__sign_bit & __diff);
+
+ return __a + __half_diff;
+}
+
+template <class _Tp, enable_if_t<is_object_v<_Tp> && !is_void_v<_Tp> && (sizeof(_Tp) > 0), int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp* midpoint(_Tp* __a, _Tp* __b) noexcept {
+ return __a + std::midpoint(ptrdiff_t(0), __b - __a);
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr int __sign(_Tp __val) {
+ return (_Tp(0) < __val) - (__val < _Tp(0));
+}
+
+template <typename _Fp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Fp __fp_abs(_Fp __f) {
+ return __f >= 0 ? __f : -__f;
+}
+
+template <class _Fp>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<is_floating_point_v<_Fp>, _Fp> midpoint(_Fp __a, _Fp __b) noexcept {
+ constexpr _Fp __lo = numeric_limits<_Fp>::min() * 2;
+ constexpr _Fp __hi = numeric_limits<_Fp>::max() / 2;
+
+ // typical case: overflow is impossible
+ if (std::__fp_abs(__a) <= __hi && std::__fp_abs(__b) <= __hi)
+ return (__a + __b) / 2; // always correctly rounded
+ if (std::__fp_abs(__a) < __lo)
+ return __a + __b / 2; // not safe to halve a
+ if (std::__fp_abs(__b) < __lo)
+ return __a / 2 + __b; // not safe to halve b
+
+ return __a / 2 + __b / 2; // otherwise correctly rounded
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_MIDPOINT_H
diff --git a/libcxx/include/__cxx03/__numeric/partial_sum.h b/libcxx/include/__cxx03/__numeric/partial_sum.h
new file mode 100644
index 00000000000000..7c3cf7fb20b040
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/partial_sum.h
@@ -0,0 +1,66 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_PARTIAL_SUM_H
+#define _LIBCPP___NUMERIC_PARTIAL_SUM_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
+ if (__first != __last) {
+ typename iterator_traits<_InputIterator>::value_type __t(*__first);
+ *__result = __t;
+ for (++__first, (void)++__result; __first != __last; ++__first, (void)++__result) {
+#if _LIBCPP_STD_VER >= 20
+ __t = std::move(__t) + *__first;
+#else
+ __t = __t + *__first;
+#endif
+ *__result = __t;
+ }
+ }
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOperation __binary_op) {
+ if (__first != __last) {
+ typename iterator_traits<_InputIterator>::value_type __t(*__first);
+ *__result = __t;
+ for (++__first, (void)++__result; __first != __last; ++__first, (void)++__result) {
+#if _LIBCPP_STD_VER >= 20
+ __t = __binary_op(std::move(__t), *__first);
+#else
+ __t = __binary_op(__t, *__first);
+#endif
+ *__result = __t;
+ }
+ }
+ return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_PARTIAL_SUM_H
diff --git a/libcxx/include/__cxx03/__numeric/pstl.h b/libcxx/include/__cxx03/__numeric/pstl.h
new file mode 100644
index 00000000000000..7557686a3663db
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/pstl.h
@@ -0,0 +1,174 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_PSTL_H
+#define _LIBCPP___NUMERIC_PSTL_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+# include <__functional/identity.h>
+# include <__functional/operations.h>
+# include <__iterator/cpp17_iterator_concepts.h>
+# include <__iterator/iterator_traits.h>
+# include <__pstl/backend.h>
+# include <__pstl/dispatch.h>
+# include <__pstl/handle_exception.h>
+# include <__type_traits/enable_if.h>
+# include <__type_traits/is_execution_policy.h>
+# include <__type_traits/remove_cvref.h>
+# include <__utility/forward.h>
+# include <__utility/move.h>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Tp,
+ class _BinaryOperation,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp reduce(
+ _ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Tp __init, _BinaryOperation __op) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "reduce requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__reduce, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first),
+ std::move(__last),
+ std::move(__init),
+ std::move(__op));
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp
+reduce(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Tp __init) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "reduce requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__reduce, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy), std::move(__first), std::move(__last), std::move(__init), plus{});
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI __iter_value_type<_ForwardIterator>
+reduce(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "reduce requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__reduce, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first),
+ std::move(__last),
+ __iter_value_type<_ForwardIterator>(),
+ plus{});
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _Tp,
+ class _BinaryOperation1,
+ class _BinaryOperation2,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp transform_reduce(
+ _ExecutionPolicy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _Tp __init,
+ _BinaryOperation1 __reduce,
+ _BinaryOperation2 __transform) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "transform_reduce requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "transform_reduce requires ForwardIterators");
+ using _Implementation =
+ __pstl::__dispatch<__pstl::__transform_reduce_binary, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__init),
+ std::move(__reduce),
+ std::move(__transform));
+}
+
+// This overload doesn't get a customization point because it's trivial to detect (through e.g.
+// __desugars_to_v) when specializing the more general variant, which should always be preferred
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _Tp,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp transform_reduce(
+ _ExecutionPolicy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _Tp __init) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator1, "transform_reduce requires ForwardIterators");
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator2, "transform_reduce requires ForwardIterators");
+ using _Implementation =
+ __pstl::__dispatch<__pstl::__transform_reduce_binary, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__init),
+ plus{},
+ multiplies{});
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator,
+ class _Tp,
+ class _BinaryOperation,
+ class _UnaryOperation,
+ class _RawPolicy = __remove_cvref_t<_ExecutionPolicy>,
+ enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp transform_reduce(
+ _ExecutionPolicy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _Tp __init,
+ _BinaryOperation __reduce,
+ _UnaryOperation __transform) {
+ _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator, "transform_reduce requires ForwardIterators");
+ using _Implementation = __pstl::__dispatch<__pstl::__transform_reduce, __pstl::__current_configuration, _RawPolicy>;
+ return __pstl::__handle_exception<_Implementation>(
+ std::forward<_ExecutionPolicy>(__policy),
+ std::move(__first),
+ std::move(__last),
+ std::move(__init),
+ std::move(__reduce),
+ std::move(__transform));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_PSTL_H
diff --git a/libcxx/include/__cxx03/__numeric/reduce.h b/libcxx/include/__cxx03/__numeric/reduce.h
new file mode 100644
index 00000000000000..6c205bf581fb95
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/reduce.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_REDUCE_H
+#define _LIBCPP___NUMERIC_REDUCE_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator, class _Tp, class _BinaryOp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
+reduce(_InputIterator __first, _InputIterator __last, _Tp __init, _BinaryOp __b) {
+ for (; __first != __last; ++__first)
+ __init = __b(std::move(__init), *__first);
+ return __init;
+}
+
+template <class _InputIterator, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
+reduce(_InputIterator __first, _InputIterator __last, _Tp __init) {
+ return std::reduce(__first, __last, __init, std::plus<>());
+}
+
+template <class _InputIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename iterator_traits<_InputIterator>::value_type
+reduce(_InputIterator __first, _InputIterator __last) {
+ return std::reduce(__first, __last, typename iterator_traits<_InputIterator>::value_type{});
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_REDUCE_H
diff --git a/libcxx/include/__cxx03/__numeric/saturation_arithmetic.h b/libcxx/include/__cxx03/__numeric/saturation_arithmetic.h
new file mode 100644
index 00000000000000..2390b42aaec31e
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/saturation_arithmetic.h
@@ -0,0 +1,145 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_SATURATION_ARITHMETIC_H
+#define _LIBCPP___NUMERIC_SATURATION_ARITHMETIC_H
+
+#include <__assert>
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__utility/cmp.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp __add_sat(_Tp __x, _Tp __y) noexcept {
+ if (_Tp __sum; !__builtin_add_overflow(__x, __y, &__sum))
+ return __sum;
+ // Handle overflow
+ if constexpr (__libcpp_unsigned_integer<_Tp>) {
+ return std::numeric_limits<_Tp>::max();
+ } else {
+ // Signed addition overflow
+ if (__x > 0)
+ // Overflows if (x > 0 && y > 0)
+ return std::numeric_limits<_Tp>::max();
+ else
+ // Overflows if (x < 0 && y < 0)
+ return std::numeric_limits<_Tp>::min();
+ }
+}
+
+template <__libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp __sub_sat(_Tp __x, _Tp __y) noexcept {
+ if (_Tp __sub; !__builtin_sub_overflow(__x, __y, &__sub))
+ return __sub;
+ // Handle overflow
+ if constexpr (__libcpp_unsigned_integer<_Tp>) {
+ // Overflows if (x < y)
+ return std::numeric_limits<_Tp>::min();
+ } else {
+ // Signed subtration overflow
+ if (__x >= 0)
+ // Overflows if (x >= 0 && y < 0)
+ return std::numeric_limits<_Tp>::max();
+ else
+ // Overflows if (x < 0 && y > 0)
+ return std::numeric_limits<_Tp>::min();
+ }
+}
+
+template <__libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp __mul_sat(_Tp __x, _Tp __y) noexcept {
+ if (_Tp __mul; !__builtin_mul_overflow(__x, __y, &__mul))
+ return __mul;
+ // Handle overflow
+ if constexpr (__libcpp_unsigned_integer<_Tp>) {
+ return std::numeric_limits<_Tp>::max();
+ } else {
+ // Signed multiplication overflow
+ if ((__x > 0 && __y > 0) || (__x < 0 && __y < 0))
+ return std::numeric_limits<_Tp>::max();
+ // Overflows if (x < 0 && y > 0) || (x > 0 && y < 0)
+ return std::numeric_limits<_Tp>::min();
+ }
+}
+
+template <__libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp __div_sat(_Tp __x, _Tp __y) noexcept {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__y != 0, "Division by 0 is undefined");
+ if constexpr (__libcpp_unsigned_integer<_Tp>) {
+ return __x / __y;
+ } else {
+ // Handle signed division overflow
+ if (__x == std::numeric_limits<_Tp>::min() && __y == _Tp{-1})
+ return std::numeric_limits<_Tp>::max();
+ return __x / __y;
+ }
+}
+
+template <__libcpp_integer _Rp, __libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Rp __saturate_cast(_Tp __x) noexcept {
+ // Saturation is impossible edge case when ((min _Rp) < (min _Tp) && (max _Rp) > (max _Tp)) and it is expected to be
+ // optimized out by the compiler.
+
+ // Handle overflow
+ if (std::cmp_less(__x, std::numeric_limits<_Rp>::min()))
+ return std::numeric_limits<_Rp>::min();
+ if (std::cmp_greater(__x, std::numeric_limits<_Rp>::max()))
+ return std::numeric_limits<_Rp>::max();
+ // No overflow
+ return static_cast<_Rp>(__x);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+
+template <__libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp add_sat(_Tp __x, _Tp __y) noexcept {
+ return std::__add_sat(__x, __y);
+}
+
+template <__libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp sub_sat(_Tp __x, _Tp __y) noexcept {
+ return std::__sub_sat(__x, __y);
+}
+
+template <__libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp mul_sat(_Tp __x, _Tp __y) noexcept {
+ return std::__mul_sat(__x, __y);
+}
+
+template <__libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp div_sat(_Tp __x, _Tp __y) noexcept {
+ return std::__div_sat(__x, __y);
+}
+
+template <__libcpp_integer _Rp, __libcpp_integer _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Rp saturate_cast(_Tp __x) noexcept {
+ return std::__saturate_cast<_Rp>(__x);
+}
+
+#endif // _LIBCPP_STD_VER >= 26
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_SATURATION_ARITHMETIC_H
diff --git a/libcxx/include/__cxx03/__numeric/transform_exclusive_scan.h b/libcxx/include/__cxx03/__numeric/transform_exclusive_scan.h
new file mode 100644
index 00000000000000..fb88aa52cd1052
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/transform_exclusive_scan.h
@@ -0,0 +1,42 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H
+#define _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator transform_exclusive_scan(
+ _InputIterator __first, _InputIterator __last, _OutputIterator __result, _Tp __init, _BinaryOp __b, _UnaryOp __u) {
+ if (__first != __last) {
+ _Tp __saved = __init;
+ do {
+ __init = __b(__init, __u(*__first));
+ *__result = __saved;
+ __saved = __init;
+ ++__result;
+ } while (++__first != __last);
+ }
+ return __result;
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H
diff --git a/libcxx/include/__cxx03/__numeric/transform_inclusive_scan.h b/libcxx/include/__cxx03/__numeric/transform_inclusive_scan.h
new file mode 100644
index 00000000000000..2eab1a142439ad
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/transform_inclusive_scan.h
@@ -0,0 +1,52 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_TRANSFORM_INCLUSIVE_SCAN_H
+#define _LIBCPP___NUMERIC_TRANSFORM_INCLUSIVE_SCAN_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator transform_inclusive_scan(
+ _InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOp __b, _UnaryOp __u, _Tp __init) {
+ for (; __first != __last; ++__first, (void)++__result) {
+ __init = __b(__init, __u(*__first));
+ *__result = __init;
+ }
+
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryOp, class _UnaryOp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator transform_inclusive_scan(
+ _InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOp __b, _UnaryOp __u) {
+ if (__first != __last) {
+ typename iterator_traits<_InputIterator>::value_type __init = __u(*__first);
+ *__result++ = __init;
+ if (++__first != __last)
+ return std::transform_inclusive_scan(__first, __last, __result, __b, __u, __init);
+ }
+
+ return __result;
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_TRANSFORM_INCLUSIVE_SCAN_H
diff --git a/libcxx/include/__cxx03/__numeric/transform_reduce.h b/libcxx/include/__cxx03/__numeric/transform_reduce.h
new file mode 100644
index 00000000000000..f1150510f0c36f
--- /dev/null
+++ b/libcxx/include/__cxx03/__numeric/transform_reduce.h
@@ -0,0 +1,59 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
+#define _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
+transform_reduce(_InputIterator __first, _InputIterator __last, _Tp __init, _BinaryOp __b, _UnaryOp __u) {
+ for (; __first != __last; ++__first)
+ __init = __b(std::move(__init), __u(*__first));
+ return __init;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Tp, class _BinaryOp1, class _BinaryOp2>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp transform_reduce(
+ _InputIterator1 __first1,
+ _InputIterator1 __last1,
+ _InputIterator2 __first2,
+ _Tp __init,
+ _BinaryOp1 __b1,
+ _BinaryOp2 __b2) {
+ for (; __first1 != __last1; ++__first1, (void)++__first2)
+ __init = __b1(std::move(__init), __b2(*__first1, *__first2));
+ return __init;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
+transform_reduce(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _Tp __init) {
+ return std::transform_reduce(__first1, __last1, __first2, std::move(__init), std::plus<>(), std::multiplies<>());
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
diff --git a/libcxx/include/__cxx03/__ostream/basic_ostream.h b/libcxx/include/__cxx03/__ostream/basic_ostream.h
new file mode 100644
index 00000000000000..178359d6815671
--- /dev/null
+++ b/libcxx/include/__cxx03/__ostream/basic_ostream.h
@@ -0,0 +1,860 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___OSTREAM_BASIC_OSTREAM_H
+#define _LIBCPP___OSTREAM_BASIC_OSTREAM_H
+
+#include <__config>
+#include <__exception/operations.h>
+#include <__memory/shared_ptr.h>
+#include <__memory/unique_ptr.h>
+#include <__system_error/error_code.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_base_of.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <bitset>
+#include <cstddef>
+#include <ios>
+#include <locale>
+#include <new> // for __throw_bad_alloc
+#include <streambuf>
+#include <string_view>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_ostream : virtual public basic_ios<_CharT, _Traits> {
+public:
+ // types (inherited from basic_ios (27.5.4)):
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ // 27.7.2.2 Constructor/destructor:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 explicit basic_ostream(basic_streambuf<char_type, traits_type>* __sb) {
+ this->init(__sb);
+ }
+ ~basic_ostream() override;
+
+ basic_ostream(const basic_ostream& __rhs) = delete;
+ basic_ostream& operator=(const basic_ostream& __rhs) = delete;
+
+protected:
+ inline _LIBCPP_HIDE_FROM_ABI basic_ostream(basic_ostream&& __rhs);
+
+ // 27.7.2.3 Assign/swap
+ inline _LIBCPP_HIDE_FROM_ABI basic_ostream& operator=(basic_ostream&& __rhs);
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void swap(basic_ostream& __rhs) {
+ basic_ios<char_type, traits_type>::swap(__rhs);
+ }
+
+public:
+ // 27.7.2.4 Prefix/suffix:
+ class _LIBCPP_TEMPLATE_VIS sentry;
+
+ // 27.7.2.6 Formatted output:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_ostream& operator<<(basic_ostream& (*__pf)(basic_ostream&)) {
+ return __pf(*this);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_ostream&
+ operator<<(basic_ios<char_type, traits_type>& (*__pf)(basic_ios<char_type, traits_type>&)) {
+ __pf(*this);
+ return *this;
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_ostream& operator<<(ios_base& (*__pf)(ios_base&)) {
+ __pf(*this);
+ return *this;
+ }
+
+ basic_ostream& operator<<(bool __n);
+ basic_ostream& operator<<(short __n);
+ basic_ostream& operator<<(unsigned short __n);
+ basic_ostream& operator<<(int __n);
+ basic_ostream& operator<<(unsigned int __n);
+ basic_ostream& operator<<(long __n);
+ basic_ostream& operator<<(unsigned long __n);
+ basic_ostream& operator<<(long long __n);
+ basic_ostream& operator<<(unsigned long long __n);
+ basic_ostream& operator<<(float __f);
+ basic_ostream& operator<<(double __f);
+ basic_ostream& operator<<(long double __f);
+ basic_ostream& operator<<(const void* __p);
+
+#if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI basic_ostream& operator<<(const volatile void* __p) {
+ return operator<<(const_cast<const void*>(__p));
+ }
+#endif
+
+ basic_ostream& operator<<(basic_streambuf<char_type, traits_type>* __sb);
+
+#if _LIBCPP_STD_VER >= 17
+ // LWG 2221 - nullptr. This is not backported to older standards modes.
+ // See https://reviews.llvm.org/D127033 for more info on the rationale.
+ _LIBCPP_HIDE_FROM_ABI basic_ostream& operator<<(nullptr_t) { return *this << "nullptr"; }
+#endif
+
+ // 27.7.2.7 Unformatted output:
+ basic_ostream& put(char_type __c);
+ basic_ostream& write(const char_type* __s, streamsize __n);
+ basic_ostream& flush();
+
+ // 27.7.2.5 seeks:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 pos_type tellp();
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_ostream& seekp(pos_type __pos);
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_ostream& seekp(off_type __off, ios_base::seekdir __dir);
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI basic_ostream() {} // extension, intentially does not initialize
+};
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_ostream<_CharT, _Traits>::sentry {
+ bool __ok_;
+ basic_ostream<_CharT, _Traits>& __os_;
+
+public:
+ explicit sentry(basic_ostream<_CharT, _Traits>& __os);
+ ~sentry();
+ sentry(const sentry&) = delete;
+ sentry& operator=(const sentry&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const { return __ok_; }
+};
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>::sentry::sentry(basic_ostream<_CharT, _Traits>& __os) : __ok_(false), __os_(__os) {
+ if (__os.good()) {
+ if (__os.tie())
+ __os.tie()->flush();
+ __ok_ = true;
+ }
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>::sentry::~sentry() {
+ if (__os_.rdbuf() && __os_.good() && (__os_.flags() & ios_base::unitbuf) && !uncaught_exception()) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (__os_.rdbuf()->pubsync() == -1)
+ __os_.setstate(ios_base::badbit);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>::basic_ostream(basic_ostream&& __rhs) {
+ this->move(__rhs);
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator=(basic_ostream&& __rhs) {
+ swap(__rhs);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>::~basic_ostream() {}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>&
+basic_ostream<_CharT, _Traits>::operator<<(basic_streambuf<char_type, traits_type>* __sb) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ if (__sb) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef istreambuf_iterator<_CharT, _Traits> _Ip;
+ typedef ostreambuf_iterator<_CharT, _Traits> _Op;
+ _Ip __i(__sb);
+ _Ip __eof;
+ _Op __o(*this);
+ size_t __c = 0;
+ for (; __i != __eof; ++__i, ++__o, ++__c) {
+ *__o = *__i;
+ if (__o.failed())
+ break;
+ }
+ if (__c == 0)
+ this->setstate(ios_base::failbit);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_failbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ } else
+ this->setstate(ios_base::badbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(bool __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), __n).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(short __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ ios_base::fmtflags __flags = ios_base::flags() & ios_base::basefield;
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this,
+ *this,
+ this->fill(),
+ __flags == ios_base::oct || __flags == ios_base::hex
+ ? static_cast<long>(static_cast<unsigned short>(__n))
+ : static_cast<long>(__n))
+ .failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(unsigned short __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), static_cast<unsigned long>(__n)).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(int __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ ios_base::fmtflags __flags = ios_base::flags() & ios_base::basefield;
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this,
+ *this,
+ this->fill(),
+ __flags == ios_base::oct || __flags == ios_base::hex
+ ? static_cast<long>(static_cast<unsigned int>(__n))
+ : static_cast<long>(__n))
+ .failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(unsigned int __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), static_cast<unsigned long>(__n)).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(long __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), __n).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(unsigned long __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), __n).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(long long __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), __n).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(unsigned long long __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), __n).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(float __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), static_cast<double>(__n)).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(double __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), __n).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(long double __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), __n).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::operator<<(const void* __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
+ const _Fp& __f = std::use_facet<_Fp>(this->getloc());
+ if (__f.put(*this, *this, this->fill(), __n).failed())
+ this->setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+__put_character_sequence(basic_ostream<_CharT, _Traits>& __os, const _CharT* __str, size_t __len) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typename basic_ostream<_CharT, _Traits>::sentry __s(__os);
+ if (__s) {
+ typedef ostreambuf_iterator<_CharT, _Traits> _Ip;
+ if (std::__pad_and_output(
+ _Ip(__os),
+ __str,
+ (__os.flags() & ios_base::adjustfield) == ios_base::left ? __str + __len : __str,
+ __str + __len,
+ __os,
+ __os.fill())
+ .failed())
+ __os.setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __os.__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return __os;
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& __os, _CharT __c) {
+ return std::__put_character_sequence(__os, &__c, 1);
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& __os, char __cn) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typename basic_ostream<_CharT, _Traits>::sentry __s(__os);
+ if (__s) {
+ _CharT __c = __os.widen(__cn);
+ typedef ostreambuf_iterator<_CharT, _Traits> _Ip;
+ if (std::__pad_and_output(
+ _Ip(__os),
+ &__c,
+ (__os.flags() & ios_base::adjustfield) == ios_base::left ? &__c + 1 : &__c,
+ &__c + 1,
+ __os,
+ __os.fill())
+ .failed())
+ __os.setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __os.__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return __os;
+}
+
+template <class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>& __os, char __c) {
+ return std::__put_character_sequence(__os, &__c, 1);
+}
+
+template <class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>& __os, signed char __c) {
+ return std::__put_character_sequence(__os, (char*)&__c, 1);
+}
+
+template <class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>& __os, unsigned char __c) {
+ return std::__put_character_sequence(__os, (char*)&__c, 1);
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const _CharT* __str) {
+ return std::__put_character_sequence(__os, __str, _Traits::length(__str));
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const char* __strn) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typename basic_ostream<_CharT, _Traits>::sentry __s(__os);
+ if (__s) {
+ typedef ostreambuf_iterator<_CharT, _Traits> _Ip;
+ size_t __len = char_traits<char>::length(__strn);
+ const int __bs = 100;
+ _CharT __wbb[__bs];
+ _CharT* __wb = __wbb;
+ unique_ptr<_CharT, void (*)(void*)> __h(0, free);
+ if (__len > __bs) {
+ __wb = (_CharT*)malloc(__len * sizeof(_CharT));
+ if (__wb == 0)
+ __throw_bad_alloc();
+ __h.reset(__wb);
+ }
+ for (_CharT* __p = __wb; *__strn != '\0'; ++__strn, ++__p)
+ *__p = __os.widen(*__strn);
+ if (std::__pad_and_output(
+ _Ip(__os),
+ __wb,
+ (__os.flags() & ios_base::adjustfield) == ios_base::left ? __wb + __len : __wb,
+ __wb + __len,
+ __os,
+ __os.fill())
+ .failed())
+ __os.setstate(ios_base::badbit | ios_base::failbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __os.__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return __os;
+}
+
+template <class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>& __os, const char* __str) {
+ return std::__put_character_sequence(__os, __str, _Traits::length(__str));
+}
+
+template <class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<char, _Traits>&
+operator<<(basic_ostream<char, _Traits>& __os, const signed char* __str) {
+ const char* __s = (const char*)__str;
+ return std::__put_character_sequence(__os, __s, _Traits::length(__s));
+}
+
+template <class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<char, _Traits>&
+operator<<(basic_ostream<char, _Traits>& __os, const unsigned char* __str) {
+ const char* __s = (const char*)__str;
+ return std::__put_character_sequence(__os, __s, _Traits::length(__s));
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::put(char_type __c) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __s(*this);
+ if (__s) {
+ typedef ostreambuf_iterator<_CharT, _Traits> _Op;
+ _Op __o(*this);
+ *__o = __c;
+ if (__o.failed())
+ this->setstate(ios_base::badbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::write(const char_type* __s, streamsize __n) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ sentry __sen(*this);
+ if (__sen && __n) {
+ if (this->rdbuf()->sputn(__s, __n) != __n)
+ this->setstate(ios_base::badbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::flush() {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (this->rdbuf()) {
+ sentry __s(*this);
+ if (__s) {
+ if (this->rdbuf()->pubsync() == -1)
+ this->setstate(ios_base::badbit);
+ }
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+typename basic_ostream<_CharT, _Traits>::pos_type basic_ostream<_CharT, _Traits>::tellp() {
+ if (this->fail())
+ return pos_type(-1);
+ return this->rdbuf()->pubseekoff(0, ios_base::cur, ios_base::out);
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::seekp(pos_type __pos) {
+ sentry __s(*this);
+ if (!this->fail()) {
+ if (this->rdbuf()->pubseekpos(__pos, ios_base::out) == pos_type(-1))
+ this->setstate(ios_base::failbit);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::seekp(off_type __off, ios_base::seekdir __dir) {
+ sentry __s(*this);
+ if (!this->fail()) {
+ if (this->rdbuf()->pubseekoff(__off, __dir, ios_base::out) == pos_type(-1))
+ this->setstate(ios_base::failbit);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI inline basic_ostream<_CharT, _Traits>& endl(basic_ostream<_CharT, _Traits>& __os) {
+ __os.put(__os.widen('\n'));
+ __os.flush();
+ return __os;
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI inline basic_ostream<_CharT, _Traits>& ends(basic_ostream<_CharT, _Traits>& __os) {
+ __os.put(_CharT());
+ return __os;
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI inline basic_ostream<_CharT, _Traits>& flush(basic_ostream<_CharT, _Traits>& __os) {
+ __os.flush();
+ return __os;
+}
+
+template <class _Stream, class _Tp, class = void>
+struct __is_ostreamable : false_type {};
+
+template <class _Stream, class _Tp>
+struct __is_ostreamable<_Stream, _Tp, decltype(std::declval<_Stream>() << std::declval<_Tp>(), void())> : true_type {};
+
+template <class _Stream,
+ class _Tp,
+ __enable_if_t<_And<is_base_of<ios_base, _Stream>, __is_ostreamable<_Stream&, const _Tp&> >::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Stream&& operator<<(_Stream&& __os, const _Tp& __x) {
+ __os << __x;
+ return std::move(__os);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const basic_string<_CharT, _Traits, _Allocator>& __str) {
+ return std::__put_character_sequence(__os, __str.data(), __str.size());
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, basic_string_view<_CharT, _Traits> __sv) {
+ return std::__put_character_sequence(__os, __sv.data(), __sv.size());
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const error_code& __ec) {
+ return __os << __ec.category().name() << ':' << __ec.value();
+}
+
+template <class _CharT, class _Traits, class _Yp>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p) {
+ return __os << __p.get();
+}
+
+template <
+ class _CharT,
+ class _Traits,
+ class _Yp,
+ class _Dp,
+ __enable_if_t<is_same<void,
+ __void_t<decltype((std::declval<basic_ostream<_CharT, _Traits>&>()
+ << std::declval<typename unique_ptr<_Yp, _Dp>::pointer>()))> >::value,
+ int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, unique_ptr<_Yp, _Dp> const& __p) {
+ return __os << __p.get();
+}
+
+template <class _CharT, class _Traits, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const bitset<_Size>& __x) {
+ return __os << __x.template to_string<_CharT, _Traits>(std::use_facet<ctype<_CharT> >(__os.getloc()).widen('0'),
+ std::use_facet<ctype<_CharT> >(__os.getloc()).widen('1'));
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _Traits>
+basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, wchar_t) = delete;
+
+template <class _Traits>
+basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, const wchar_t*) = delete;
+
+template <class _Traits>
+basic_ostream<wchar_t, _Traits>& operator<<(basic_ostream<wchar_t, _Traits>&, char16_t) = delete;
+
+template <class _Traits>
+basic_ostream<wchar_t, _Traits>& operator<<(basic_ostream<wchar_t, _Traits>&, char32_t) = delete;
+
+template <class _Traits>
+basic_ostream<wchar_t, _Traits>& operator<<(basic_ostream<wchar_t, _Traits>&, const char16_t*) = delete;
+
+template <class _Traits>
+basic_ostream<wchar_t, _Traits>& operator<<(basic_ostream<wchar_t, _Traits>&, const char32_t*) = delete;
+
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <class _Traits>
+basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, char8_t) = delete;
+
+template <class _Traits>
+basic_ostream<wchar_t, _Traits>& operator<<(basic_ostream<wchar_t, _Traits>&, char8_t) = delete;
+
+template <class _Traits>
+basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, const char8_t*) = delete;
+
+template <class _Traits>
+basic_ostream<wchar_t, _Traits>& operator<<(basic_ostream<wchar_t, _Traits>&, const char8_t*) = delete;
+# endif
+
+template <class _Traits>
+basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, char16_t) = delete;
+
+template <class _Traits>
+basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, char32_t) = delete;
+
+template <class _Traits>
+basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, const char16_t*) = delete;
+
+template <class _Traits>
+basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, const char32_t*) = delete;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<char>;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<wchar_t>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___OSTREAM_BASIC_OSTREAM_H
diff --git a/libcxx/include/__cxx03/__ostream/print.h b/libcxx/include/__cxx03/__ostream/print.h
new file mode 100644
index 00000000000000..8265ac00777e25
--- /dev/null
+++ b/libcxx/include/__cxx03/__ostream/print.h
@@ -0,0 +1,179 @@
+//===---------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___OSTREAM_PRINT_H
+#define _LIBCPP___OSTREAM_PRINT_H
+
+#include <__config>
+#include <__fwd/ostream.h>
+#include <__iterator/ostreambuf_iterator.h>
+#include <__ostream/basic_ostream.h>
+#include <format>
+#include <ios>
+#include <locale>
+#include <print>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void
+__vprint_nonunicode(ostream& __os, string_view __fmt, format_args __args, bool __write_nl) {
+ // [ostream.formatted.print]/3
+ // Effects: Behaves as a formatted output function
+ // ([ostream.formatted.reqmts]) of os, except that:
+ // - failure to generate output is reported as specified below, and
+ // - any exception thrown by the call to vformat is propagated without regard
+ // to the value of os.exceptions() and without turning on ios_base::badbit
+ // in the error state of os.
+ // After constructing a sentry object, the function initializes an automatic
+ // variable via
+ // string out = vformat(os.getloc(), fmt, args);
+
+ ostream::sentry __s(__os);
+ if (__s) {
+ string __o = std::vformat(__os.getloc(), __fmt, __args);
+ if (__write_nl)
+ __o += '\n';
+
+ const char* __str = __o.data();
+ size_t __len = __o.size();
+
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef ostreambuf_iterator<char> _Ip;
+ if (std::__pad_and_output(
+ _Ip(__os),
+ __str,
+ (__os.flags() & ios_base::adjustfield) == ios_base::left ? __str + __len : __str,
+ __str + __len,
+ __os,
+ __os.fill())
+ .failed())
+ __os.setstate(ios_base::badbit | ios_base::failbit);
+
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __os.__set_badbit_and_consider_rethrow();
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void vprint_nonunicode(ostream& __os, string_view __fmt, format_args __args) {
+ std::__vprint_nonunicode(__os, __fmt, __args, false);
+}
+
+// Returns the FILE* associated with the __os.
+// Returns a nullptr when no FILE* is associated with __os.
+// This function is in the dylib since the type of the buffer associated
+// with std::cout, std::cerr, and std::clog is only known in the dylib.
+//
+// This function implements part of the implementation-defined behavior
+// of [ostream.formatted.print]/3
+// If the function is vprint_unicode and os is a stream that refers to
+// a terminal capable of displaying Unicode which is determined in an
+// implementation-defined manner, writes out to the terminal using the
+// native Unicode API;
+// Whether the returned FILE* is "a terminal capable of displaying Unicode"
+// is determined in the same way as the print(FILE*, ...) overloads.
+_LIBCPP_EXPORTED_FROM_ABI FILE* __get_ostream_file(ostream& __os);
+
+# ifndef _LIBCPP_HAS_NO_UNICODE
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI void __vprint_unicode(ostream& __os, string_view __fmt, format_args __args, bool __write_nl) {
+# if _LIBCPP_AVAILABILITY_HAS_PRINT == 0
+ return std::__vprint_nonunicode(__os, __fmt, __args, __write_nl);
+# else
+ FILE* __file = std::__get_ostream_file(__os);
+ if (!__file || !__print::__is_terminal(__file))
+ return std::__vprint_nonunicode(__os, __fmt, __args, __write_nl);
+
+ // [ostream.formatted.print]/3
+ // If the function is vprint_unicode and os is a stream that refers to a
+ // terminal capable of displaying Unicode which is determined in an
+ // implementation-defined manner, writes out to the terminal using the
+ // native Unicode API; if out contains invalid code units, the behavior is
+ // undefined and implementations are encouraged to diagnose it. If the
+ // native Unicode API is used, the function flushes os before writing out.
+ //
+ // This is the path for the native API, start with flushing.
+ __os.flush();
+
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ ostream::sentry __s(__os);
+ if (__s) {
+# ifndef _LIBCPP_WIN32API
+ __print::__vprint_unicode_posix(__file, __fmt, __args, __write_nl, true);
+# elif !defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+ __print::__vprint_unicode_windows(__file, __fmt, __args, __write_nl, true);
+# else
+# error "Windows builds with wchar_t disabled are not supported."
+# endif
+ }
+
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __os.__set_badbit_and_consider_rethrow();
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+# endif // _LIBCPP_AVAILABILITY_HAS_PRINT
+}
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void vprint_unicode(ostream& __os, string_view __fmt, format_args __args) {
+ std::__vprint_unicode(__os, __fmt, __args, false);
+}
+# endif // _LIBCPP_HAS_NO_UNICODE
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void print(ostream& __os, format_string<_Args...> __fmt, _Args&&... __args) {
+# ifndef _LIBCPP_HAS_NO_UNICODE
+ if constexpr (__print::__use_unicode_execution_charset)
+ std::__vprint_unicode(__os, __fmt.get(), std::make_format_args(__args...), false);
+ else
+ std::__vprint_nonunicode(__os, __fmt.get(), std::make_format_args(__args...), false);
+# else // _LIBCPP_HAS_NO_UNICODE
+ std::__vprint_nonunicode(__os, __fmt.get(), std::make_format_args(__args...), false);
+# endif // _LIBCPP_HAS_NO_UNICODE
+}
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void println(ostream& __os, format_string<_Args...> __fmt, _Args&&... __args) {
+# ifndef _LIBCPP_HAS_NO_UNICODE
+ // Note the wording in the Standard is inefficient. The output of
+ // std::format is a std::string which is then copied. This solution
+ // just appends a newline at the end of the output.
+ if constexpr (__print::__use_unicode_execution_charset)
+ std::__vprint_unicode(__os, __fmt.get(), std::make_format_args(__args...), true);
+ else
+ std::__vprint_nonunicode(__os, __fmt.get(), std::make_format_args(__args...), true);
+# else // _LIBCPP_HAS_NO_UNICODE
+ std::__vprint_nonunicode(__os, __fmt.get(), std::make_format_args(__args...), true);
+# endif // _LIBCPP_HAS_NO_UNICODE
+}
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void println(ostream& __os) {
+ std::print(__os, "\n");
+}
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___OSTREAM_PRINT_H
diff --git a/libcxx/include/__cxx03/__pstl/backend.h b/libcxx/include/__cxx03/__pstl/backend.h
new file mode 100644
index 00000000000000..86d9f28c77fa8c
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/backend.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_BACKEND_H
+#define _LIBCPP___PSTL_BACKEND_H
+
+#include <__config>
+#include <__pstl/backend_fwd.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if defined(_LIBCPP_PSTL_BACKEND_SERIAL)
+# include <__pstl/backends/default.h>
+# include <__pstl/backends/serial.h>
+#elif defined(_LIBCPP_PSTL_BACKEND_STD_THREAD)
+# include <__pstl/backends/default.h>
+# include <__pstl/backends/std_thread.h>
+#elif defined(_LIBCPP_PSTL_BACKEND_LIBDISPATCH)
+# include <__pstl/backends/default.h>
+# include <__pstl/backends/libdispatch.h>
+#endif
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_BACKEND_H
diff --git a/libcxx/include/__cxx03/__pstl/backend_fwd.h b/libcxx/include/__cxx03/__pstl/backend_fwd.h
new file mode 100644
index 00000000000000..32c5da576fb3c0
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/backend_fwd.h
@@ -0,0 +1,301 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_BACKEND_FWD_H
+#define _LIBCPP___PSTL_BACKEND_FWD_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+//
+// This header declares available PSTL backends and the functions that must be implemented in order for the
+// PSTL algorithms to be provided.
+//
+// Backends often do not implement the full set of functions themselves -- a configuration of the PSTL is
+// usually a set of backends "stacked" together which each implement some algorithms under some execution
+// policies. It is only necessary for the "stack" of backends to implement all algorithms under all execution
+// policies, but a single backend is not required to implement everything on its own.
+//
+// The signatures used by each backend function are documented below.
+//
+// Exception handling
+// ==================
+//
+// PSTL backends are expected to report errors (i.e. failure to allocate) by returning a disengaged `optional` from
+// their implementation. Exceptions shouldn't be used to report an internal failure-to-allocate, since all exceptions
+// are turned into a program termination at the front-end level. When a backend returns a disengaged `optional` to the
+// frontend, the frontend will turn that into a call to `std::__throw_bad_alloc();` to report the internal failure to
+// the user.
+//
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class... _Backends>
+struct __backend_configuration;
+
+struct __default_backend_tag;
+struct __libdispatch_backend_tag;
+struct __serial_backend_tag;
+struct __std_thread_backend_tag;
+
+#if defined(_LIBCPP_PSTL_BACKEND_SERIAL)
+using __current_configuration = __backend_configuration<__serial_backend_tag, __default_backend_tag>;
+#elif defined(_LIBCPP_PSTL_BACKEND_STD_THREAD)
+using __current_configuration = __backend_configuration<__std_thread_backend_tag, __default_backend_tag>;
+#elif defined(_LIBCPP_PSTL_BACKEND_LIBDISPATCH)
+using __current_configuration = __backend_configuration<__libdispatch_backend_tag, __default_backend_tag>;
+#else
+
+// ...New vendors can add parallel backends here...
+
+# error "Invalid PSTL backend configuration"
+#endif
+
+template <class _Backend, class _ExecutionPolicy>
+struct __find_if;
+// template <class _Policy, class _ForwardIterator, class _Predicate>
+// optional<_ForwardIterator>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __find_if_not;
+// template <class _Policy, class _ForwardIterator, class _Predicate>
+// optional<_ForwardIterator>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __find;
+// template <class _Policy, class _ForwardIterator, class _Tp>
+// optional<_ForwardIterator>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __any_of;
+// template <class _Policy, class _ForwardIterator, class _Predicate>
+// optional<bool>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __all_of;
+// template <class _Policy, class _ForwardIterator, class _Predicate>
+// optional<bool>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __none_of;
+// template <class _Policy, class _ForwardIterator, class _Predicate>
+// optional<bool>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __is_partitioned;
+// template <class _Policy, class _ForwardIterator, class _Predicate>
+// optional<bool>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __for_each;
+// template <class _Policy, class _ForwardIterator, class _Function>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Function __func) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __for_each_n;
+// template <class _Policy, class _ForwardIterator, class _Size, class _Function>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _Size __size, _Function __func) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __fill;
+// template <class _Policy, class _ForwardIterator, class _Tp>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Tp const& __value) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __fill_n;
+// template <class _Policy, class _ForwardIterator, class _Size, class _Tp>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _Size __n, _Tp const& __value) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __replace;
+// template <class _Policy, class _ForwardIterator, class _Tp>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _Tp const& __old, _Tp const& __new) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __replace_if;
+// template <class _Policy, class _ForwardIterator, class _Predicate, class _Tp>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _Predicate __pred, _Tp const& __new_value) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __generate;
+// template <class _Policy, class _ForwardIterator, class _Generator>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Generator __gen) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __generate_n;
+// template <class _Policy, class _ForwardIterator, class _Size, class _Generator>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _Size __n, _Generator __gen) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __merge;
+// template <class _Policy, class _ForwardIterator1, class _ForwardIterator2, class _ForwardOutIterator, class _Comp>
+// optional<_ForwardOutIterator>
+// operator()(_Policy&&, _ForwardIterator1 __first1, _ForwardIterator1 __last1,
+// _ForwardIterator2 __first2, _ForwardIterator2 __last2,
+// _ForwardOutIterator __result, _Comp __comp) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __stable_sort;
+// template <class _Policy, class _RandomAccessIterator, class _Comp>
+// optional<__empty>
+// operator()(_Policy&&, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __sort;
+// template <class _Policy, class _RandomAccessIterator, class _Comp>
+// optional<__empty>
+// operator()(_Policy&&, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __transform;
+// template <class _Policy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
+// optional<_ForwardOutIterator>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _ForwardOutIterator __result,
+// _UnaryOperation __op) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __transform_binary;
+// template <class _Policy, class _ForwardIterator1, class _ForwardIterator2,
+// class _ForwardOutIterator,
+// class _BinaryOperation>
+// optional<_ForwardOutIterator>
+// operator()(_Policy&&, _ForwardIterator1 __first1, _ForwardIterator1 __last1,
+// _ForwardIterator2 __first2,
+// _ForwardOutIterator __result,
+// _BinaryOperation __op) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __replace_copy_if;
+// template <class _Policy, class _ForwardIterator, class _ForwardOutIterator, class _Predicate, class _Tp>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _ForwardOutIterator __out_it,
+// _Predicate __pred,
+// _Tp const& __new_value) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __replace_copy;
+// template <class _Policy, class _ForwardIterator, class _ForwardOutIterator, class _Tp>
+// optional<__empty>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _ForwardOutIterator __out_it,
+// _Tp const& __old_value,
+// _Tp const& __new_value) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __move;
+// template <class _Policy, class _ForwardIterator, class _ForwardOutIterator>
+// optional<_ForwardOutIterator>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _ForwardOutIterator __out_it) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __copy;
+// template <class _Policy, class _ForwardIterator, class _ForwardOutIterator>
+// optional<_ForwardOutIterator>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _ForwardOutIterator __out_it) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __copy_n;
+// template <class _Policy, class _ForwardIterator, class _Size, class _ForwardOutIterator>
+// optional<_ForwardOutIterator>
+// operator()(_Policy&&, _ForwardIterator __first, _Size __n, _ForwardOutIterator __out_it) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __rotate_copy;
+// template <class _Policy, class _ForwardIterator, class _ForwardOutIterator>
+// optional<_ForwardOutIterator>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last,
+// _ForwardOutIterator __out_it) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __transform_reduce;
+// template <class _Policy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
+// optional<_Tp>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _Tp __init,
+// _BinaryOperation __reduce,
+// _UnaryOperation __transform) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __transform_reduce_binary;
+// template <class _Policy, class _ForwardIterator1, class _ForwardIterator2,
+// class _Tp, class _BinaryOperation1, class _BinaryOperation2>
+// optional<_Tp> operator()(_Policy&&, _ForwardIterator1 __first1, _ForwardIterator1 __last1,
+// _ForwardIterator2 __first2,
+// _Tp __init,
+// _BinaryOperation1 __reduce,
+// _BinaryOperation2 __transform) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __count_if;
+// template <class _Policy, class _ForwardIterator, class _Predicate>
+// optional<__iter_diff_t<_ForwardIterator>>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __count;
+// template <class _Policy, class _ForwardIterator, class _Tp>
+// optional<__iter_diff_t<_ForwardIterator>>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Tp const& __value) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __equal_3leg;
+// template <class _Policy, class _ForwardIterator1, class _ForwardIterator2, class _Predicate>
+// optional<bool>
+// operator()(_Policy&&, _ForwardIterator1 __first1, _ForwardIterator1 __last1,
+// _ForwardIterator2 __first2,
+// _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __equal;
+// template <class _Policy, class _ForwardIterator1, class _ForwardIterator2, class _Predicate>
+// optional<bool>
+// operator()(_Policy&&, _ForwardIterator1 __first1, _ForwardIterator1 __last1,
+// _ForwardIterator2 __first2, _ForwardIterator2 __last2,
+// _Predicate __pred) const noexcept;
+
+template <class _Backend, class _ExecutionPolicy>
+struct __reduce;
+// template <class _Policy, class _ForwardIterator, class _Tp, class _BinaryOperation>
+// optional<_Tp>
+// operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last,
+// _Tp __init, _BinaryOperation __op) const noexcept;
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_BACKEND_FWD_H
diff --git a/libcxx/include/__cxx03/__pstl/backends/default.h b/libcxx/include/__cxx03/__pstl/backends/default.h
new file mode 100644
index 00000000000000..61a128805f8549
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/backends/default.h
@@ -0,0 +1,503 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_BACKENDS_DEFAULT_H
+#define _LIBCPP___PSTL_BACKENDS_DEFAULT_H
+
+#include <__algorithm/copy_n.h>
+#include <__algorithm/equal.h>
+#include <__algorithm/fill_n.h>
+#include <__algorithm/for_each_n.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/not_fn.h>
+#include <__functional/operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/dispatch.h>
+#include <__utility/empty.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+//
+// This file provides an incomplete PSTL backend that implements all of the PSTL algorithms
+// based on a smaller set of basis operations.
+//
+// It is intended as a building block for other PSTL backends that implement some operations more
+// efficiently but may not want to define the full set of PSTL algorithms.
+//
+// This backend implements all the PSTL algorithms based on the following basis operations:
+//
+// find_if family
+// --------------
+// - find
+// - find_if_not
+// - any_of
+// - all_of
+// - none_of
+// - is_partitioned
+//
+// for_each family
+// ---------------
+// - for_each_n
+// - fill
+// - fill_n
+// - replace
+// - replace_if
+// - generate
+// - generate_n
+//
+// merge family
+// ------------
+// No other algorithms based on merge
+//
+// stable_sort family
+// ------------------
+// - sort
+//
+// transform_reduce and transform_reduce_binary family
+// ---------------------------------------------------
+// - count_if
+// - count
+// - equal(3 legs)
+// - equal
+// - reduce
+//
+// transform and transform_binary family
+// -------------------------------------
+// - replace_copy_if
+// - replace_copy
+// - move
+// - copy
+// - copy_n
+// - rotate_copy
+//
+
+//////////////////////////////////////////////////////////////
+// find_if family
+//////////////////////////////////////////////////////////////
+template <class _ExecutionPolicy>
+struct __find<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) const noexcept {
+ using _FindIf = __dispatch<__find_if, __current_configuration, _ExecutionPolicy>;
+ return _FindIf()(
+ __policy, std::move(__first), std::move(__last), [&](__iter_reference<_ForwardIterator> __element) {
+ return __element == __value;
+ });
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __find_if_not<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Pred&& __pred) const noexcept {
+ using _FindIf = __dispatch<__find_if, __current_configuration, _ExecutionPolicy>;
+ return _FindIf()(__policy, __first, __last, std::not_fn(std::forward<_Pred>(__pred)));
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __any_of<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<bool>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Pred&& __pred) const noexcept {
+ using _FindIf = __dispatch<__find_if, __current_configuration, _ExecutionPolicy>;
+ auto __res = _FindIf()(__policy, __first, __last, std::forward<_Pred>(__pred));
+ if (!__res)
+ return nullopt;
+ return *__res != __last;
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __all_of<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<bool>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Pred&& __pred) const noexcept {
+ using _AnyOf = __dispatch<__any_of, __current_configuration, _ExecutionPolicy>;
+ auto __res = _AnyOf()(__policy, __first, __last, [&](__iter_reference<_ForwardIterator> __value) {
+ return !__pred(__value);
+ });
+ if (!__res)
+ return nullopt;
+ return !*__res;
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __none_of<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<bool>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Pred&& __pred) const noexcept {
+ using _AnyOf = __dispatch<__any_of, __current_configuration, _ExecutionPolicy>;
+ auto __res = _AnyOf()(__policy, __first, __last, std::forward<_Pred>(__pred));
+ if (!__res)
+ return nullopt;
+ return !*__res;
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __is_partitioned<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<bool>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Pred&& __pred) const noexcept {
+ using _FindIfNot = __dispatch<__find_if_not, __current_configuration, _ExecutionPolicy>;
+ auto __maybe_first = _FindIfNot()(__policy, std::move(__first), std::move(__last), __pred);
+ if (__maybe_first == nullopt)
+ return nullopt;
+
+ __first = *__maybe_first;
+ if (__first == __last)
+ return true;
+ ++__first;
+ using _NoneOf = __dispatch<__none_of, __current_configuration, _ExecutionPolicy>;
+ return _NoneOf()(__policy, std::move(__first), std::move(__last), __pred);
+ }
+};
+
+//////////////////////////////////////////////////////////////
+// for_each family
+//////////////////////////////////////////////////////////////
+template <class _ExecutionPolicy>
+struct __for_each_n<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Size, class _Function>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _Size __size, _Function __func) const noexcept {
+ if constexpr (__has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ using _ForEach = __dispatch<__for_each, __current_configuration, _ExecutionPolicy>;
+ _ForwardIterator __last = __first + __size;
+ return _ForEach()(__policy, std::move(__first), std::move(__last), std::move(__func));
+ } else {
+ // Otherwise, use the serial algorithm to avoid doing two passes over the input
+ std::for_each_n(std::move(__first), __size, std::move(__func));
+ return __empty{};
+ }
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __fill<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Tp const& __value) const noexcept {
+ using _ForEach = __dispatch<__for_each, __current_configuration, _ExecutionPolicy>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ return _ForEach()(__policy, std::move(__first), std::move(__last), [&](_Ref __element) { __element = __value; });
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __fill_n<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Size, class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _Size __n, _Tp const& __value) const noexcept {
+ if constexpr (__has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ using _Fill = __dispatch<__fill, __current_configuration, _ExecutionPolicy>;
+ _ForwardIterator __last = __first + __n;
+ return _Fill()(__policy, std::move(__first), std::move(__last), __value);
+ } else {
+ // Otherwise, use the serial algorithm to avoid doing two passes over the input
+ std::fill_n(std::move(__first), __n, __value);
+ return optional<__empty>{__empty{}};
+ }
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __replace<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Tp const& __old, _Tp const& __new)
+ const noexcept {
+ using _ReplaceIf = __dispatch<__replace_if, __current_configuration, _ExecutionPolicy>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ return _ReplaceIf()(
+ __policy, std::move(__first), std::move(__last), [&](_Ref __element) { return __element == __old; }, __new);
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __replace_if<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Pred, class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty> operator()(
+ _Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Pred&& __pred, _Tp const& __new_value)
+ const noexcept {
+ using _ForEach = __dispatch<__for_each, __current_configuration, _ExecutionPolicy>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ return _ForEach()(__policy, std::move(__first), std::move(__last), [&](_Ref __element) {
+ if (__pred(__element))
+ __element = __new_value;
+ });
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __generate<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Generator>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Generator&& __gen) const noexcept {
+ using _ForEach = __dispatch<__for_each, __current_configuration, _ExecutionPolicy>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ return _ForEach()(__policy, std::move(__first), std::move(__last), [&](_Ref __element) { __element = __gen(); });
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __generate_n<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Size, class _Generator>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _Size __n, _Generator&& __gen) const noexcept {
+ using _ForEachN = __dispatch<__for_each_n, __current_configuration, _ExecutionPolicy>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ return _ForEachN()(__policy, std::move(__first), __n, [&](_Ref __element) { __element = __gen(); });
+ }
+};
+
+//////////////////////////////////////////////////////////////
+// stable_sort family
+//////////////////////////////////////////////////////////////
+template <class _ExecutionPolicy>
+struct __sort<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _RandomAccessIterator, class _Comp>
+ _LIBCPP_HIDE_FROM_ABI optional<__empty> operator()(
+ _Policy&& __policy, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp&& __comp) const noexcept {
+ using _StableSort = __dispatch<__stable_sort, __current_configuration, _ExecutionPolicy>;
+ return _StableSort()(__policy, std::move(__first), std::move(__last), std::forward<_Comp>(__comp));
+ }
+};
+
+//////////////////////////////////////////////////////////////
+// transform_reduce family
+//////////////////////////////////////////////////////////////
+template <class _ExecutionPolicy>
+struct __count_if<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Predicate>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__iter_diff_t<_ForwardIterator>> operator()(
+ _Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate&& __pred) const noexcept {
+ using _TransformReduce = __dispatch<__transform_reduce, __current_configuration, _ExecutionPolicy>;
+ using _DiffT = __iter_diff_t<_ForwardIterator>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ return _TransformReduce()(
+ __policy, std::move(__first), std::move(__last), _DiffT{}, std::plus{}, [&](_Ref __element) -> _DiffT {
+ return __pred(__element) ? _DiffT(1) : _DiffT(0);
+ });
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __count<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__iter_diff_t<_ForwardIterator>>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Tp const& __value) const noexcept {
+ using _CountIf = __dispatch<__count_if, __current_configuration, _ExecutionPolicy>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ return _CountIf()(__policy, std::move(__first), std::move(__last), [&](_Ref __element) -> bool {
+ return __element == __value;
+ });
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __equal_3leg<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator1, class _ForwardIterator2, class _Predicate>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<bool>
+ operator()(_Policy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _Predicate&& __pred) const noexcept {
+ using _TransformReduce = __dispatch<__transform_reduce_binary, __current_configuration, _ExecutionPolicy>;
+ return _TransformReduce()(
+ __policy,
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ true,
+ std::logical_and{},
+ std::forward<_Predicate>(__pred));
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __equal<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator1, class _ForwardIterator2, class _Predicate>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<bool>
+ operator()(_Policy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _Predicate&& __pred) const noexcept {
+ if constexpr (__has_random_access_iterator_category<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category<_ForwardIterator2>::value) {
+ if (__last1 - __first1 != __last2 - __first2)
+ return false;
+ // Fall back to the 3 legged algorithm
+ using _Equal3Leg = __dispatch<__equal_3leg, __current_configuration, _ExecutionPolicy>;
+ return _Equal3Leg()(
+ __policy, std::move(__first1), std::move(__last1), std::move(__first2), std::forward<_Predicate>(__pred));
+ } else {
+ // If we don't have random access, fall back to the serial algorithm cause we can't do much
+ return std::equal(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::forward<_Predicate>(__pred));
+ }
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __reduce<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Tp, class _BinaryOperation>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<_Tp>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Tp __init, _BinaryOperation&& __op)
+ const noexcept {
+ using _TransformReduce = __dispatch<__transform_reduce, __current_configuration, _ExecutionPolicy>;
+ return _TransformReduce()(
+ __policy,
+ std::move(__first),
+ std::move(__last),
+ std::move(__init),
+ std::forward<_BinaryOperation>(__op),
+ __identity{});
+ }
+};
+
+//////////////////////////////////////////////////////////////
+// transform family
+//////////////////////////////////////////////////////////////
+template <class _ExecutionPolicy>
+struct __replace_copy_if<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _ForwardOutIterator, class _Pred, class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _ForwardOutIterator __out_it,
+ _Pred&& __pred,
+ _Tp const& __new_value) const noexcept {
+ using _Transform = __dispatch<__transform, __current_configuration, _ExecutionPolicy>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ auto __res =
+ _Transform()(__policy, std::move(__first), std::move(__last), std::move(__out_it), [&](_Ref __element) {
+ return __pred(__element) ? __new_value : __element;
+ });
+ if (__res == nullopt)
+ return nullopt;
+ return __empty{};
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __replace_copy<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _ForwardOutIterator, class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _ForwardOutIterator __out_it,
+ _Tp const& __old_value,
+ _Tp const& __new_value) const noexcept {
+ using _ReplaceCopyIf = __dispatch<__replace_copy_if, __current_configuration, _ExecutionPolicy>;
+ using _Ref = __iter_reference<_ForwardIterator>;
+ return _ReplaceCopyIf()(
+ __policy,
+ std::move(__first),
+ std::move(__last),
+ std::move(__out_it),
+ [&](_Ref __element) { return __element == __old_value; },
+ __new_value);
+ }
+};
+
+// TODO: Use the std::copy/move shenanigans to forward to std::memmove
+// Investigate whether we want to still forward to std::transform(policy)
+// in that case for the execution::par part, or whether we actually want
+// to run everything serially in that case.
+template <class _ExecutionPolicy>
+struct __move<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _ForwardOutIterator>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _ForwardOutIterator __out_it)
+ const noexcept {
+ using _Transform = __dispatch<__transform, __current_configuration, _ExecutionPolicy>;
+ return _Transform()(__policy, std::move(__first), std::move(__last), std::move(__out_it), [&](auto&& __element) {
+ return std::move(__element);
+ });
+ }
+};
+
+// TODO: Use the std::copy/move shenanigans to forward to std::memmove
+template <class _ExecutionPolicy>
+struct __copy<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _ForwardOutIterator>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _ForwardOutIterator __out_it)
+ const noexcept {
+ using _Transform = __dispatch<__transform, __current_configuration, _ExecutionPolicy>;
+ return _Transform()(__policy, std::move(__first), std::move(__last), std::move(__out_it), __identity());
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __copy_n<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Size, class _ForwardOutIterator>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _Size __n, _ForwardOutIterator __out_it) const noexcept {
+ if constexpr (__has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ using _Copy = __dispatch<__copy, __current_configuration, _ExecutionPolicy>;
+ _ForwardIterator __last = __first + __n;
+ return _Copy()(__policy, std::move(__first), std::move(__last), std::move(__out_it));
+ } else {
+ // Otherwise, use the serial algorithm to avoid doing two passes over the input
+ return std::copy_n(std::move(__first), __n, std::move(__out_it));
+ }
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __rotate_copy<__default_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _ForwardOutIterator>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator>
+ operator()(_Policy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __middle,
+ _ForwardIterator __last,
+ _ForwardOutIterator __out_it) const noexcept {
+ using _Copy = __dispatch<__copy, __current_configuration, _ExecutionPolicy>;
+ auto __result_mid = _Copy()(__policy, __middle, std::move(__last), std::move(__out_it));
+ if (__result_mid == nullopt)
+ return nullopt;
+ return _Copy()(__policy, std::move(__first), std::move(__middle), *std::move(__result_mid));
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_BACKENDS_DEFAULT_H
diff --git a/libcxx/include/__cxx03/__pstl/backends/libdispatch.h b/libcxx/include/__cxx03/__pstl/backends/libdispatch.h
new file mode 100644
index 00000000000000..a0c3ad980ed1b0
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/backends/libdispatch.h
@@ -0,0 +1,397 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_BACKENDS_LIBDISPATCH_H
+#define _LIBCPP___PSTL_BACKENDS_LIBDISPATCH_H
+
+#include <__algorithm/inplace_merge.h>
+#include <__algorithm/lower_bound.h>
+#include <__algorithm/max.h>
+#include <__algorithm/merge.h>
+#include <__algorithm/upper_bound.h>
+#include <__atomic/atomic.h>
+#include <__config>
+#include <__exception/terminate.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/move_iterator.h>
+#include <__memory/allocator.h>
+#include <__memory/construct_at.h>
+#include <__memory/unique_ptr.h>
+#include <__numeric/reduce.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/any_of.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__pstl/cpu_algos/fill.h>
+#include <__pstl/cpu_algos/find_if.h>
+#include <__pstl/cpu_algos/for_each.h>
+#include <__pstl/cpu_algos/merge.h>
+#include <__pstl/cpu_algos/stable_sort.h>
+#include <__pstl/cpu_algos/transform.h>
+#include <__pstl/cpu_algos/transform_reduce.h>
+#include <__utility/empty.h>
+#include <__utility/exception_guard.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <cstddef>
+#include <new>
+#include <optional>
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+namespace __libdispatch {
+// ::dispatch_apply is marked as __attribute__((nothrow)) because it doesn't let exceptions propagate, and neither do
+// we.
+// TODO: Do we want to add [[_Clang::__callback__(__func, __context, __)]]?
+_LIBCPP_EXPORTED_FROM_ABI void
+__dispatch_apply(size_t __chunk_count, void* __context, void (*__func)(void* __context, size_t __chunk)) noexcept;
+
+template <class _Func>
+_LIBCPP_HIDE_FROM_ABI void __dispatch_apply(size_t __chunk_count, _Func __func) noexcept {
+ __libdispatch::__dispatch_apply(__chunk_count, &__func, [](void* __context, size_t __chunk) {
+ (*static_cast<_Func*>(__context))(__chunk);
+ });
+}
+
+struct __chunk_partitions {
+ ptrdiff_t __chunk_count_; // includes the first chunk
+ ptrdiff_t __chunk_size_;
+ ptrdiff_t __first_chunk_size_;
+};
+
+[[__gnu__::__const__]] _LIBCPP_EXPORTED_FROM_ABI __chunk_partitions __partition_chunks(ptrdiff_t __size) noexcept;
+
+template <class _RandomAccessIterator, class _Functor>
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
+__dispatch_parallel_for(__chunk_partitions __partitions, _RandomAccessIterator __first, _Functor __func) {
+ // Perform the chunked execution.
+ __libdispatch::__dispatch_apply(__partitions.__chunk_count_, [&](size_t __chunk) {
+ auto __this_chunk_size = __chunk == 0 ? __partitions.__first_chunk_size_ : __partitions.__chunk_size_;
+ auto __index =
+ __chunk == 0
+ ? 0
+ : (__chunk * __partitions.__chunk_size_) + (__partitions.__first_chunk_size_ - __partitions.__chunk_size_);
+ __func(__first + __index, __first + __index + __this_chunk_size);
+ });
+
+ return __empty{};
+}
+} // namespace __libdispatch
+
+template <>
+struct __cpu_traits<__libdispatch_backend_tag> {
+ template <class _RandomAccessIterator, class _Functor>
+ _LIBCPP_HIDE_FROM_ABI static optional<__empty>
+ __for_each(_RandomAccessIterator __first, _RandomAccessIterator __last, _Functor __func) {
+ return __libdispatch::__dispatch_parallel_for(
+ __libdispatch::__partition_chunks(__last - __first), std::move(__first), std::move(__func));
+ }
+
+ template <class _RandomAccessIterator1, class _RandomAccessIterator2, class _RandomAccessIteratorOut>
+ struct __merge_range {
+ __merge_range(_RandomAccessIterator1 __mid1, _RandomAccessIterator2 __mid2, _RandomAccessIteratorOut __result)
+ : __mid1_(__mid1), __mid2_(__mid2), __result_(__result) {}
+
+ _RandomAccessIterator1 __mid1_;
+ _RandomAccessIterator2 __mid2_;
+ _RandomAccessIteratorOut __result_;
+ };
+
+ template <typename _RandomAccessIterator1,
+ typename _RandomAccessIterator2,
+ typename _RandomAccessIterator3,
+ typename _Compare,
+ typename _LeafMerge>
+ _LIBCPP_HIDE_FROM_ABI static optional<__empty>
+ __merge(_RandomAccessIterator1 __first1,
+ _RandomAccessIterator1 __last1,
+ _RandomAccessIterator2 __first2,
+ _RandomAccessIterator2 __last2,
+ _RandomAccessIterator3 __result,
+ _Compare __comp,
+ _LeafMerge __leaf_merge) noexcept {
+ __libdispatch::__chunk_partitions __partitions =
+ __libdispatch::__partition_chunks(std::max<ptrdiff_t>(__last1 - __first1, __last2 - __first2));
+
+ if (__partitions.__chunk_count_ == 0)
+ return __empty{};
+
+ if (__partitions.__chunk_count_ == 1) {
+ __leaf_merge(__first1, __last1, __first2, __last2, __result, __comp);
+ return __empty{};
+ }
+
+ using __merge_range_t = __merge_range<_RandomAccessIterator1, _RandomAccessIterator2, _RandomAccessIterator3>;
+ auto const __n_ranges = __partitions.__chunk_count_ + 1;
+
+ // TODO: use __uninitialized_buffer
+ auto __destroy = [=](__merge_range_t* __ptr) {
+ std::destroy_n(__ptr, __n_ranges);
+ std::allocator<__merge_range_t>().deallocate(__ptr, __n_ranges);
+ };
+
+ unique_ptr<__merge_range_t[], decltype(__destroy)> __ranges(
+ [&]() -> __merge_range_t* {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ return std::allocator<__merge_range_t>().allocate(__n_ranges);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (const std::bad_alloc&) {
+ return nullptr;
+ }
+#endif
+ }(),
+ __destroy);
+
+ if (!__ranges)
+ return nullopt;
+
+ // TODO: Improve the case where the smaller range is merged into just a few (or even one) chunks of the larger case
+ __merge_range_t* __r = __ranges.get();
+ std::__construct_at(__r++, __first1, __first2, __result);
+
+ bool __iterate_first_range = __last1 - __first1 > __last2 - __first2;
+
+ auto __compute_chunk = [&](size_t __chunk_size) -> __merge_range_t {
+ auto [__mid1, __mid2] = [&] {
+ if (__iterate_first_range) {
+ auto __m1 = __first1 + __chunk_size;
+ auto __m2 = std::lower_bound(__first2, __last2, __m1[-1], __comp);
+ return std::make_pair(__m1, __m2);
+ } else {
+ auto __m2 = __first2 + __chunk_size;
+ auto __m1 = std::lower_bound(__first1, __last1, __m2[-1], __comp);
+ return std::make_pair(__m1, __m2);
+ }
+ }();
+
+ __result += (__mid1 - __first1) + (__mid2 - __first2);
+ __first1 = __mid1;
+ __first2 = __mid2;
+ return {std::move(__mid1), std::move(__mid2), __result};
+ };
+
+ // handle first chunk
+ std::__construct_at(__r++, __compute_chunk(__partitions.__first_chunk_size_));
+
+ // handle 2 -> N - 1 chunks
+ for (ptrdiff_t __i = 0; __i != __partitions.__chunk_count_ - 2; ++__i)
+ std::__construct_at(__r++, __compute_chunk(__partitions.__chunk_size_));
+
+ // handle last chunk
+ std::__construct_at(__r, __last1, __last2, __result);
+
+ __libdispatch::__dispatch_apply(__partitions.__chunk_count_, [&](size_t __index) {
+ auto __first_iters = __ranges[__index];
+ auto __last_iters = __ranges[__index + 1];
+ __leaf_merge(
+ __first_iters.__mid1_,
+ __last_iters.__mid1_,
+ __first_iters.__mid2_,
+ __last_iters.__mid2_,
+ __first_iters.__result_,
+ __comp);
+ });
+
+ return __empty{};
+ }
+
+ template <class _RandomAccessIterator, class _Transform, class _Value, class _Combiner, class _Reduction>
+ _LIBCPP_HIDE_FROM_ABI static optional<_Value> __transform_reduce(
+ _RandomAccessIterator __first,
+ _RandomAccessIterator __last,
+ _Transform __transform,
+ _Value __init,
+ _Combiner __combiner,
+ _Reduction __reduction) {
+ if (__first == __last)
+ return __init;
+
+ auto __partitions = __libdispatch::__partition_chunks(__last - __first);
+
+ auto __destroy = [__count = __partitions.__chunk_count_](_Value* __ptr) {
+ std::destroy_n(__ptr, __count);
+ std::allocator<_Value>().deallocate(__ptr, __count);
+ };
+
+ // TODO: use __uninitialized_buffer
+ // TODO: allocate one element per worker instead of one element per chunk
+ unique_ptr<_Value[], decltype(__destroy)> __values(
+ std::allocator<_Value>().allocate(__partitions.__chunk_count_), __destroy);
+
+ // __dispatch_apply is noexcept
+ __libdispatch::__dispatch_apply(__partitions.__chunk_count_, [&](size_t __chunk) {
+ auto __this_chunk_size = __chunk == 0 ? __partitions.__first_chunk_size_ : __partitions.__chunk_size_;
+ auto __index = __chunk == 0 ? 0
+ : (__chunk * __partitions.__chunk_size_) +
+ (__partitions.__first_chunk_size_ - __partitions.__chunk_size_);
+ if (__this_chunk_size != 1) {
+ std::__construct_at(
+ __values.get() + __chunk,
+ __reduction(__first + __index + 2,
+ __first + __index + __this_chunk_size,
+ __combiner(__transform(__first + __index), __transform(__first + __index + 1))));
+ } else {
+ std::__construct_at(__values.get() + __chunk, __transform(__first + __index));
+ }
+ });
+
+ return std::reduce(
+ std::make_move_iterator(__values.get()),
+ std::make_move_iterator(__values.get() + __partitions.__chunk_count_),
+ std::move(__init),
+ __combiner);
+ }
+
+ template <class _RandomAccessIterator, class _Comp, class _LeafSort>
+ _LIBCPP_HIDE_FROM_ABI static optional<__empty>
+ __stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp, _LeafSort __leaf_sort) {
+ const auto __size = __last - __first;
+ auto __partitions = __libdispatch::__partition_chunks(__size);
+
+ if (__partitions.__chunk_count_ == 0)
+ return __empty{};
+
+ if (__partitions.__chunk_count_ == 1) {
+ __leaf_sort(__first, __last, __comp);
+ return __empty{};
+ }
+
+ using _Value = __iter_value_type<_RandomAccessIterator>;
+
+ auto __destroy = [__size](_Value* __ptr) {
+ std::destroy_n(__ptr, __size);
+ std::allocator<_Value>().deallocate(__ptr, __size);
+ };
+
+ // TODO: use __uninitialized_buffer
+ unique_ptr<_Value[], decltype(__destroy)> __values(std::allocator<_Value>().allocate(__size), __destroy);
+
+ // Initialize all elements to a moved-from state
+ // TODO: Don't do this - this can be done in the first merge - see https://llvm.org/PR63928
+ std::__construct_at(__values.get(), std::move(*__first));
+ for (__iter_diff_t<_RandomAccessIterator> __i = 1; __i != __size; ++__i) {
+ std::__construct_at(__values.get() + __i, std::move(__values.get()[__i - 1]));
+ }
+ *__first = std::move(__values.get()[__size - 1]);
+
+ __libdispatch::__dispatch_parallel_for(
+ __partitions,
+ __first,
+ [&__leaf_sort, &__comp](_RandomAccessIterator __chunk_first, _RandomAccessIterator __chunk_last) {
+ __leaf_sort(std::move(__chunk_first), std::move(__chunk_last), __comp);
+ });
+
+ bool __objects_are_in_buffer = false;
+ do {
+ const auto __old_chunk_size = __partitions.__chunk_size_;
+ if (__partitions.__chunk_count_ % 2 == 1) {
+ auto __inplace_merge_chunks = [&__comp, &__partitions](auto __first_chunk_begin) {
+ std::inplace_merge(
+ __first_chunk_begin,
+ __first_chunk_begin + __partitions.__first_chunk_size_,
+ __first_chunk_begin + __partitions.__first_chunk_size_ + __partitions.__chunk_size_,
+ __comp);
+ };
+ if (__objects_are_in_buffer)
+ __inplace_merge_chunks(__values.get());
+ else
+ __inplace_merge_chunks(__first);
+ __partitions.__first_chunk_size_ += 2 * __partitions.__chunk_size_;
+ } else {
+ __partitions.__first_chunk_size_ += __partitions.__chunk_size_;
+ }
+
+ __partitions.__chunk_size_ *= 2;
+ __partitions.__chunk_count_ /= 2;
+
+ auto __merge_chunks = [__partitions, __old_chunk_size, &__comp](auto __from_first, auto __to_first) {
+ __libdispatch::__dispatch_parallel_for(
+ __partitions,
+ __from_first,
+ [__old_chunk_size, &__from_first, &__to_first, &__comp](auto __chunk_first, auto __chunk_last) {
+ std::merge(std::make_move_iterator(__chunk_first),
+ std::make_move_iterator(__chunk_last - __old_chunk_size),
+ std::make_move_iterator(__chunk_last - __old_chunk_size),
+ std::make_move_iterator(__chunk_last),
+ __to_first + (__chunk_first - __from_first),
+ __comp);
+ });
+ };
+
+ if (__objects_are_in_buffer)
+ __merge_chunks(__values.get(), __first);
+ else
+ __merge_chunks(__first, __values.get());
+ __objects_are_in_buffer = !__objects_are_in_buffer;
+ } while (__partitions.__chunk_count_ > 1);
+
+ if (__objects_are_in_buffer) {
+ std::move(__values.get(), __values.get() + __size, __first);
+ }
+
+ return __empty{};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void __cancel_execution() {}
+
+ static constexpr size_t __lane_size = 64;
+};
+
+// Mandatory implementations of the computational basis
+template <class _ExecutionPolicy>
+struct __find_if<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_find_if<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __for_each<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_for_each<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __merge<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_merge<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __stable_sort<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_stable_sort<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __transform<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_transform<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __transform_binary<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_transform_binary<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __transform_reduce<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_transform_reduce<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __transform_reduce_binary<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_transform_reduce_binary<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+// Not mandatory, but better optimized
+template <class _ExecutionPolicy>
+struct __any_of<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_any_of<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __fill<__libdispatch_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_fill<__libdispatch_backend_tag, _ExecutionPolicy> {};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_BACKENDS_LIBDISPATCH_H
diff --git a/libcxx/include/__cxx03/__pstl/backends/serial.h b/libcxx/include/__cxx03/__pstl/backends/serial.h
new file mode 100644
index 00000000000000..5f24499899bd20
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/backends/serial.h
@@ -0,0 +1,181 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_BACKENDS_SERIAL_H
+#define _LIBCPP___PSTL_BACKENDS_SERIAL_H
+
+#include <__algorithm/find_if.h>
+#include <__algorithm/for_each.h>
+#include <__algorithm/merge.h>
+#include <__algorithm/stable_sort.h>
+#include <__algorithm/transform.h>
+#include <__config>
+#include <__numeric/transform_reduce.h>
+#include <__pstl/backend_fwd.h>
+#include <__utility/empty.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+//
+// This partial PSTL backend runs everything serially.
+//
+// TODO: Right now, the serial backend must be used with another backend
+// like the "default backend" because it doesn't implement all the
+// necessary PSTL operations. It would be better to dispatch all
+// algorithms to their serial counterpart directly, since this can
+// often be more efficient than the "default backend"'s implementation
+// if we end up running serially anyways.
+//
+
+template <class _ExecutionPolicy>
+struct __find_if<__serial_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Pred>
+ _LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
+ operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Pred&& __pred) const noexcept {
+ return std::find_if(std::move(__first), std::move(__last), std::forward<_Pred>(__pred));
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __for_each<__serial_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Function>
+ _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&&, _ForwardIterator __first, _ForwardIterator __last, _Function&& __func) const noexcept {
+ std::for_each(std::move(__first), std::move(__last), std::forward<_Function>(__func));
+ return __empty{};
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __merge<__serial_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator1, class _ForwardIterator2, class _ForwardOutIterator, class _Comp>
+ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> operator()(
+ _Policy&&,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _ForwardOutIterator __outit,
+ _Comp&& __comp) const noexcept {
+ return std::merge(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__last2),
+ std::move(__outit),
+ std::forward<_Comp>(__comp));
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __stable_sort<__serial_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _RandomAccessIterator, class _Comp>
+ _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&&, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp&& __comp) const noexcept {
+ std::stable_sort(std::move(__first), std::move(__last), std::forward<_Comp>(__comp));
+ return __empty{};
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __transform<__serial_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> operator()(
+ _Policy&&, _ForwardIterator __first, _ForwardIterator __last, _ForwardOutIterator __outit, _UnaryOperation&& __op)
+ const noexcept {
+ return std::transform(
+ std::move(__first), std::move(__last), std::move(__outit), std::forward<_UnaryOperation>(__op));
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __transform_binary<__serial_backend_tag, _ExecutionPolicy> {
+ template <class _Policy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _ForwardOutIterator,
+ class _BinaryOperation>
+ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator>
+ operator()(_Policy&&,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardOutIterator __outit,
+ _BinaryOperation&& __op) const noexcept {
+ return std::transform(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__outit),
+ std::forward<_BinaryOperation>(__op));
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __transform_reduce<__serial_backend_tag, _ExecutionPolicy> {
+ template <class _Policy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI optional<_Tp>
+ operator()(_Policy&&,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _Tp __init,
+ _BinaryOperation&& __reduce,
+ _UnaryOperation&& __transform) const noexcept {
+ return std::transform_reduce(
+ std::move(__first),
+ std::move(__last),
+ std::move(__init),
+ std::forward<_BinaryOperation>(__reduce),
+ std::forward<_UnaryOperation>(__transform));
+ }
+};
+
+template <class _ExecutionPolicy>
+struct __transform_reduce_binary<__serial_backend_tag, _ExecutionPolicy> {
+ template <class _Policy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _Tp,
+ class _BinaryOperation1,
+ class _BinaryOperation2>
+ _LIBCPP_HIDE_FROM_ABI optional<_Tp> operator()(
+ _Policy&&,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _Tp __init,
+ _BinaryOperation1&& __reduce,
+ _BinaryOperation2&& __transform) const noexcept {
+ return std::transform_reduce(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__init),
+ std::forward<_BinaryOperation1>(__reduce),
+ std::forward<_BinaryOperation2>(__transform));
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_BACKENDS_SERIAL_H
diff --git a/libcxx/include/__cxx03/__pstl/backends/std_thread.h b/libcxx/include/__cxx03/__pstl/backends/std_thread.h
new file mode 100644
index 00000000000000..49570bd30b0828
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/backends/std_thread.h
@@ -0,0 +1,136 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_BACKENDS_STD_THREAD_H
+#define _LIBCPP___PSTL_BACKENDS_STD_THREAD_H
+
+#include <__config>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/any_of.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__pstl/cpu_algos/fill.h>
+#include <__pstl/cpu_algos/find_if.h>
+#include <__pstl/cpu_algos/for_each.h>
+#include <__pstl/cpu_algos/merge.h>
+#include <__pstl/cpu_algos/stable_sort.h>
+#include <__pstl/cpu_algos/transform.h>
+#include <__pstl/cpu_algos/transform_reduce.h>
+#include <__utility/empty.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+//
+// This partial backend implementation is for testing purposes only and not meant for production use. This will be
+// replaced by a proper implementation once the PSTL implementation is somewhat stable.
+//
+// This is intended to be used on top of the "default backend".
+//
+
+template <>
+struct __cpu_traits<__std_thread_backend_tag> {
+ template <class _RandomAccessIterator, class _Fp>
+ _LIBCPP_HIDE_FROM_ABI static optional<__empty>
+ __for_each(_RandomAccessIterator __first, _RandomAccessIterator __last, _Fp __f) {
+ __f(__first, __last);
+ return __empty{};
+ }
+
+ template <class _Index, class _UnaryOp, class _Tp, class _BinaryOp, class _Reduce>
+ _LIBCPP_HIDE_FROM_ABI static optional<_Tp>
+ __transform_reduce(_Index __first, _Index __last, _UnaryOp, _Tp __init, _BinaryOp, _Reduce __reduce) {
+ return __reduce(std::move(__first), std::move(__last), std::move(__init));
+ }
+
+ template <class _RandomAccessIterator, class _Compare, class _LeafSort>
+ _LIBCPP_HIDE_FROM_ABI static optional<__empty>
+ __stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp, _LeafSort __leaf_sort) {
+ __leaf_sort(__first, __last, __comp);
+ return __empty{};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void __cancel_execution() {}
+
+ template <class _RandomAccessIterator1,
+ class _RandomAccessIterator2,
+ class _RandomAccessIterator3,
+ class _Compare,
+ class _LeafMerge>
+ _LIBCPP_HIDE_FROM_ABI static optional<__empty>
+ __merge(_RandomAccessIterator1 __first1,
+ _RandomAccessIterator1 __last1,
+ _RandomAccessIterator2 __first2,
+ _RandomAccessIterator2 __last2,
+ _RandomAccessIterator3 __outit,
+ _Compare __comp,
+ _LeafMerge __leaf_merge) {
+ __leaf_merge(__first1, __last1, __first2, __last2, __outit, __comp);
+ return __empty{};
+ }
+
+ static constexpr size_t __lane_size = 64;
+};
+
+// Mandatory implementations of the computational basis
+template <class _ExecutionPolicy>
+struct __find_if<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_find_if<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __for_each<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_for_each<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __merge<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_merge<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __stable_sort<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_stable_sort<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __transform<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_transform<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __transform_binary<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_transform_binary<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __transform_reduce<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_transform_reduce<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __transform_reduce_binary<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_transform_reduce_binary<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+// Not mandatory, but better optimized
+template <class _ExecutionPolicy>
+struct __any_of<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_any_of<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+template <class _ExecutionPolicy>
+struct __fill<__std_thread_backend_tag, _ExecutionPolicy>
+ : __cpu_parallel_fill<__std_thread_backend_tag, _ExecutionPolicy> {};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_BACKENDS_STD_THREAD_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/any_of.h b/libcxx/include/__cxx03/__pstl/cpu_algos/any_of.h
new file mode 100644
index 00000000000000..b33c787a29db26
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/any_of.h
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_ANY_OF_H
+#define _LIBCPP___PSTL_CPU_ALGOS_ANY_OF_H
+
+#include <__algorithm/any_of.h>
+#include <__assert>
+#include <__atomic/atomic.h>
+#include <__atomic/memory_order.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <cstdint>
+#include <optional>
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class _Backend, class _Index, class _Brick>
+_LIBCPP_HIDE_FROM_ABI optional<bool> __parallel_or(_Index __first, _Index __last, _Brick __f) {
+ std::atomic<bool> __found(false);
+ auto __ret = __cpu_traits<_Backend>::__for_each(__first, __last, [__f, &__found](_Index __i, _Index __j) {
+ if (!__found.load(std::memory_order_relaxed) && __f(__i, __j)) {
+ __found.store(true, std::memory_order_relaxed);
+ __cpu_traits<_Backend>::__cancel_execution();
+ }
+ });
+ if (!__ret)
+ return nullopt;
+ return static_cast<bool>(__found);
+}
+
+// TODO: check whether __simd_first() can be used here
+template <class _Index, class _DifferenceType, class _Pred>
+_LIBCPP_HIDE_FROM_ABI bool __simd_or(_Index __first, _DifferenceType __n, _Pred __pred) noexcept {
+ _DifferenceType __block_size = 4 < __n ? 4 : __n;
+ const _Index __last = __first + __n;
+ while (__last != __first) {
+ int32_t __flag = 1;
+ _PSTL_PRAGMA_SIMD_REDUCTION(& : __flag)
+ for (_DifferenceType __i = 0; __i < __block_size; ++__i)
+ if (__pred(*(__first + __i)))
+ __flag = 0;
+ if (!__flag)
+ return true;
+
+ __first += __block_size;
+ if (__last - __first >= __block_size << 1) {
+ // Double the block _Size. Any unnecessary iterations can be amortized against work done so far.
+ __block_size <<= 1;
+ } else {
+ __block_size = __last - __first;
+ }
+ }
+ return false;
+}
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_any_of {
+ template <class _Policy, class _ForwardIterator, class _Predicate>
+ _LIBCPP_HIDE_FROM_ABI optional<bool>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return __pstl::__parallel_or<_Backend>(
+ __first, __last, [&__policy, &__pred](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
+ using _AnyOfUnseq = __pstl::__any_of<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ auto __res = _AnyOfUnseq()(std::__remove_parallel_policy(__policy), __brick_first, __brick_last, __pred);
+ _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!");
+ return *std::move(__res);
+ });
+ } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return __pstl::__simd_or(__first, __last - __first, __pred);
+ } else {
+ return std::any_of(__first, __last, __pred);
+ }
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_ANY_OF_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/cpu_traits.h b/libcxx/include/__cxx03/__pstl/cpu_algos/cpu_traits.h
new file mode 100644
index 00000000000000..0483d6918fd01d
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/cpu_traits.h
@@ -0,0 +1,86 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_CPU_TRAITS_H
+#define _LIBCPP___PSTL_CPU_ALGOS_CPU_TRAITS_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+// __cpu_traits
+//
+// This traits class encapsulates the basis operations for a CPU-based implementation of the PSTL.
+// All the operations in the PSTL can be implemented from these basis operations, so a pure CPU backend
+// only needs to customize these traits in order to get an implementation of the whole PSTL.
+//
+// Basis operations
+// ================
+//
+// template <class _RandomAccessIterator, class _Functor>
+// optional<__empty> __for_each(_RandomAccessIterator __first, _RandomAccessIterator __last, _Functor __func);
+// - __func must take a subrange of [__first, __last) that should be executed in serial
+//
+// template <class _Iterator, class _UnaryOp, class _Tp, class _BinaryOp, class _Reduction>
+// optional<_Tp> __transform_reduce(_Iterator __first, _Iterator __last, _UnaryOp, _Tp __init, _BinaryOp, _Reduction);
+//
+// template <class _RandomAccessIterator1,
+// class _RandomAccessIterator2,
+// class _RandomAccessIterator3,
+// class _Compare,
+// class _LeafMerge>
+// optional<_RandomAccessIterator3> __merge(_RandomAccessIterator1 __first1,
+// _RandomAccessIterator1 __last1,
+// _RandomAccessIterator2 __first2,
+// _RandomAccessIterator2 __last2,
+// _RandomAccessIterator3 __outit,
+// _Compare __comp,
+// _LeafMerge __leaf_merge);
+//
+// template <class _RandomAccessIterator, class _Comp, class _LeafSort>
+// optional<__empty> __stable_sort(_RandomAccessIterator __first,
+// _RandomAccessIterator __last,
+// _Comp __comp,
+// _LeafSort __leaf_sort);
+//
+// void __cancel_execution();
+// Cancel the execution of other jobs - they aren't needed anymore. This is not a binding request,
+// some backends may not actually be able to cancel jobs.
+//
+// constexpr size_t __lane_size;
+// Size of SIMD lanes.
+// TODO: Merge this with __native_vector_size from __algorithm/simd_utils.h
+//
+//
+// Exception handling
+// ==================
+//
+// CPU backends are expected to report errors (i.e. failure to allocate) by returning a disengaged `optional` from their
+// implementation. Exceptions shouldn't be used to report an internal failure-to-allocate, since all exceptions are
+// turned into a program termination at the front-end level. When a backend returns a disengaged `optional` to the
+// frontend, the frontend will turn that into a call to `std::__throw_bad_alloc();` to report the internal failure to
+// the user.
+
+template <class _Backend>
+struct __cpu_traits;
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_CPU_TRAITS_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/fill.h b/libcxx/include/__cxx03/__pstl/cpu_algos/fill.h
new file mode 100644
index 00000000000000..4e6d29b30cc69d
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/fill.h
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_FILL_H
+#define _LIBCPP___PSTL_CPU_ALGOS_FILL_H
+
+#include <__algorithm/fill.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/empty.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class _Index, class _DifferenceType, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Index __simd_fill_n(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
+ _PSTL_USE_NONTEMPORAL_STORES_IF_ALLOWED
+ _PSTL_PRAGMA_SIMD
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __first[__i] = __value;
+ return __first + __n;
+}
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_fill {
+ template <class _Policy, class _ForwardIterator, class _Tp>
+ _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return __cpu_traits<_Backend>::__for_each(
+ __first, __last, [&__policy, &__value](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
+ using _FillUnseq = __pstl::__fill<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ [[maybe_unused]] auto __res =
+ _FillUnseq()(std::__remove_parallel_policy(__policy), __brick_first, __brick_last, __value);
+ _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!");
+ });
+ } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ __pstl::__simd_fill_n(__first, __last - __first, __value);
+ return __empty{};
+ } else {
+ std::fill(__first, __last, __value);
+ return __empty{};
+ }
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_FILL_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/find_if.h b/libcxx/include/__cxx03/__pstl/cpu_algos/find_if.h
new file mode 100644
index 00000000000000..12b2e88971df7d
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/find_if.h
@@ -0,0 +1,137 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_FIND_IF_H
+#define _LIBCPP___PSTL_CPU_ALGOS_FIND_IF_H
+
+#include <__algorithm/find_if.h>
+#include <__assert>
+#include <__atomic/atomic.h>
+#include <__config>
+#include <__functional/operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <cstddef>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class _Backend, class _Index, class _Brick, class _Compare>
+_LIBCPP_HIDE_FROM_ABI optional<_Index>
+__parallel_find(_Index __first, _Index __last, _Brick __f, _Compare __comp, bool __b_first) {
+ typedef typename std::iterator_traits<_Index>::difference_type _DifferenceType;
+ const _DifferenceType __n = __last - __first;
+ _DifferenceType __initial_dist = __b_first ? __n : -1;
+ std::atomic<_DifferenceType> __extremum(__initial_dist);
+ // TODO: find out what is better here: parallel_for or parallel_reduce
+ auto __res =
+ __cpu_traits<_Backend>::__for_each(__first, __last, [__comp, __f, __first, &__extremum](_Index __i, _Index __j) {
+ // See "Reducing Contention Through Priority Updates", PPoPP '13, for discussion of
+ // why using a shared variable scales fairly well in this situation.
+ if (__comp(__i - __first, __extremum)) {
+ _Index __result = __f(__i, __j);
+ // If not '__last' returned then we found what we want so put this to extremum
+ if (__result != __j) {
+ const _DifferenceType __k = __result - __first;
+ for (_DifferenceType __old = __extremum; __comp(__k, __old); __old = __extremum) {
+ __extremum.compare_exchange_weak(__old, __k);
+ }
+ }
+ }
+ });
+ if (!__res)
+ return nullopt;
+ return __extremum.load() != __initial_dist ? __first + __extremum.load() : __last;
+}
+
+template <class _Backend, class _Index, class _DifferenceType, class _Compare>
+_LIBCPP_HIDE_FROM_ABI _Index
+__simd_first(_Index __first, _DifferenceType __begin, _DifferenceType __end, _Compare __comp) noexcept {
+ // Experiments show good block sizes like this
+ const _DifferenceType __block_size = 8;
+ alignas(__cpu_traits<_Backend>::__lane_size) _DifferenceType __lane[__block_size] = {0};
+ while (__end - __begin >= __block_size) {
+ _DifferenceType __found = 0;
+ _PSTL_PRAGMA_SIMD_REDUCTION(| : __found) for (_DifferenceType __i = __begin; __i < __begin + __block_size; ++__i) {
+ const _DifferenceType __t = __comp(__first, __i);
+ __lane[__i - __begin] = __t;
+ __found |= __t;
+ }
+ if (__found) {
+ _DifferenceType __i;
+ // This will vectorize
+ for (__i = 0; __i < __block_size; ++__i) {
+ if (__lane[__i]) {
+ break;
+ }
+ }
+ return __first + __begin + __i;
+ }
+ __begin += __block_size;
+ }
+
+ // Keep remainder scalar
+ while (__begin != __end) {
+ if (__comp(__first, __begin)) {
+ return __first + __begin;
+ }
+ ++__begin;
+ }
+ return __first + __end;
+}
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_find_if {
+ template <class _Policy, class _ForwardIterator, class _Predicate>
+ _LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return __pstl::__parallel_find<_Backend>(
+ __first,
+ __last,
+ [&__policy, &__pred](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
+ using _FindIfUnseq = __pstl::__find_if<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ auto __res = _FindIfUnseq()(std::__remove_parallel_policy(__policy), __brick_first, __brick_last, __pred);
+ _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!");
+ return *std::move(__res);
+ },
+ less<>{},
+ true);
+ } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ using __diff_t = __iter_diff_t<_ForwardIterator>;
+ return __pstl::__simd_first<_Backend>(
+ __first, __diff_t(0), __last - __first, [&__pred](_ForwardIterator __iter, __diff_t __i) {
+ return __pred(__iter[__i]);
+ });
+ } else {
+ return std::find_if(__first, __last, __pred);
+ }
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_FIND_IF_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/for_each.h b/libcxx/include/__cxx03/__pstl/cpu_algos/for_each.h
new file mode 100644
index 00000000000000..d4d7862135ff91
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/for_each.h
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_FOR_EACH_H
+#define _LIBCPP___PSTL_CPU_ALGOS_FOR_EACH_H
+
+#include <__algorithm/for_each.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/empty.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class _Iterator, class _DifferenceType, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator __simd_for_each(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
+ _PSTL_PRAGMA_SIMD
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(__first[__i]);
+
+ return __first + __n;
+}
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_for_each {
+ template <class _Policy, class _ForwardIterator, class _Function>
+ _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Function __func) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return __cpu_traits<_Backend>::__for_each(
+ __first, __last, [&__policy, __func](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
+ using _ForEachUnseq = __pstl::__for_each<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ [[maybe_unused]] auto __res =
+ _ForEachUnseq()(std::__remove_parallel_policy(__policy), __brick_first, __brick_last, __func);
+ _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!");
+ });
+ } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ __pstl::__simd_for_each(__first, __last - __first, __func);
+ return __empty{};
+ } else {
+ std::for_each(__first, __last, __func);
+ return __empty{};
+ }
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_FOR_EACH_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/merge.h b/libcxx/include/__cxx03/__pstl/cpu_algos/merge.h
new file mode 100644
index 00000000000000..dfa4cbf69b1470
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/merge.h
@@ -0,0 +1,85 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_MERGE_H
+#define _LIBCPP___PSTL_CPU_ALGOS_MERGE_H
+
+#include <__algorithm/merge.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/move.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_merge {
+ template <class _Policy, class _ForwardIterator1, class _ForwardIterator2, class _ForwardOutIterator, class _Comp>
+ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> operator()(
+ _Policy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _ForwardOutIterator __result,
+ _Comp __comp) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ auto __res = __cpu_traits<_Backend>::__merge(
+ __first1,
+ __last1,
+ __first2,
+ __last2,
+ __result,
+ __comp,
+ [&__policy](_ForwardIterator1 __g_first1,
+ _ForwardIterator1 __g_last1,
+ _ForwardIterator2 __g_first2,
+ _ForwardIterator2 __g_last2,
+ _ForwardOutIterator __g_result,
+ _Comp __g_comp) {
+ using _MergeUnseq = __pstl::__merge<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ [[maybe_unused]] auto __g_res = _MergeUnseq()(
+ std::__remove_parallel_policy(__policy),
+ std::move(__g_first1),
+ std::move(__g_last1),
+ std::move(__g_first2),
+ std::move(__g_last2),
+ std::move(__g_result),
+ std::move(__g_comp));
+ _LIBCPP_ASSERT_INTERNAL(__g_res, "unsed/sed should never try to allocate!");
+ });
+ if (!__res)
+ return nullopt;
+ return __result + (__last1 - __first1) + (__last2 - __first2);
+ } else {
+ return std::merge(__first1, __last1, __first2, __last2, __result, __comp);
+ }
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_MERGE_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/stable_sort.h b/libcxx/include/__cxx03/__pstl/cpu_algos/stable_sort.h
new file mode 100644
index 00000000000000..8e64f3e537c072
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/stable_sort.h
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_STABLE_SORT_H
+#define _LIBCPP___PSTL_CPU_ALGOS_STABLE_SORT_H
+
+#include <__algorithm/stable_sort.h>
+#include <__config>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/empty.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_stable_sort {
+ template <class _Policy, class _RandomAccessIterator, class _Comp>
+ _LIBCPP_HIDE_FROM_ABI optional<__empty>
+ operator()(_Policy&&, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy>) {
+ return __cpu_traits<_Backend>::__stable_sort(
+ __first, __last, __comp, [](_RandomAccessIterator __g_first, _RandomAccessIterator __g_last, _Comp __g_comp) {
+ std::stable_sort(__g_first, __g_last, __g_comp);
+ });
+ } else {
+ std::stable_sort(__first, __last, __comp);
+ return __empty{};
+ }
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_STABLE_SORT_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/transform.h b/libcxx/include/__cxx03/__pstl/cpu_algos/transform.h
new file mode 100644
index 00000000000000..27ce8e27b242af
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/transform.h
@@ -0,0 +1,153 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_TRANSFORM_H
+#define _LIBCPP___PSTL_CPU_ALGOS_TRANSFORM_H
+
+#include <__algorithm/transform.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/move.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator2
+__simd_transform(_Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f) noexcept {
+ _PSTL_PRAGMA_SIMD
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(__first1[__i], __first2[__i]);
+ return __first2 + __n;
+}
+
+template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Iterator3, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator3 __simd_transform(
+ _Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Iterator3 __first3, _Function __f) noexcept {
+ _PSTL_PRAGMA_SIMD
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(__first1[__i], __first2[__i], __first3[__i]);
+ return __first3 + __n;
+}
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_transform {
+ template <class _Policy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator>
+ operator()(_Policy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _ForwardOutIterator __result,
+ _UnaryOperation __op) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ __cpu_traits<_Backend>::__for_each(
+ __first,
+ __last,
+ [&__policy, __op, __first, __result](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
+ using _TransformUnseq = __pstl::__transform<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ auto __res = _TransformUnseq()(
+ std::__remove_parallel_policy(__policy),
+ __brick_first,
+ __brick_last,
+ __result + (__brick_first - __first),
+ __op);
+ _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!");
+ return *std::move(__res);
+ });
+ return __result + (__last - __first);
+ } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ return __pstl::__simd_transform(
+ __first,
+ __last - __first,
+ __result,
+ [&](__iter_reference<_ForwardIterator> __in_value, __iter_reference<_ForwardOutIterator> __out_value) {
+ __out_value = __op(__in_value);
+ });
+ } else {
+ return std::transform(__first, __last, __result, __op);
+ }
+ }
+};
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_transform_binary {
+ template <class _Policy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _ForwardOutIterator,
+ class _BinaryOperation>
+ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator>
+ operator()(_Policy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardOutIterator __result,
+ _BinaryOperation __op) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ auto __res = __cpu_traits<_Backend>::__for_each(
+ __first1,
+ __last1,
+ [&__policy, __op, __first1, __first2, __result](
+ _ForwardIterator1 __brick_first, _ForwardIterator1 __brick_last) {
+ using _TransformBinaryUnseq =
+ __pstl::__transform_binary<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ return _TransformBinaryUnseq()(
+ std::__remove_parallel_policy(__policy),
+ __brick_first,
+ __brick_last,
+ __first2 + (__brick_first - __first1),
+ __result + (__brick_first - __first1),
+ __op);
+ });
+ if (!__res)
+ return nullopt;
+ return __result + (__last1 - __first1);
+ } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ return __pstl::__simd_transform(
+ __first1,
+ __last1 - __first1,
+ __first2,
+ __result,
+ [&](__iter_reference<_ForwardIterator1> __in1,
+ __iter_reference<_ForwardIterator2> __in2,
+ __iter_reference<_ForwardOutIterator> __out_value) { __out_value = __op(__in1, __in2); });
+ } else {
+ return std::transform(__first1, __last1, __first2, __result, __op);
+ }
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_TRANSFORM_H
diff --git a/libcxx/include/__cxx03/__pstl/cpu_algos/transform_reduce.h b/libcxx/include/__cxx03/__pstl/cpu_algos/transform_reduce.h
new file mode 100644
index 00000000000000..36ac1a9072a89e
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/cpu_algos/transform_reduce.h
@@ -0,0 +1,216 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_CPU_ALGOS_TRANSFORM_REDUCE_H
+#define _LIBCPP___PSTL_CPU_ALGOS_TRANSFORM_REDUCE_H
+
+#include <__assert>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__numeric/transform_reduce.h>
+#include <__pstl/backend_fwd.h>
+#include <__pstl/cpu_algos/cpu_traits.h>
+#include <__type_traits/desugars_to.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <new>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <typename _Backend,
+ typename _DifferenceType,
+ typename _Tp,
+ typename _BinaryOperation,
+ typename _UnaryOperation,
+ typename _UnaryResult = invoke_result_t<_UnaryOperation, _DifferenceType>,
+ __enable_if_t<__desugars_to_v<__plus_tag, _BinaryOperation, _Tp, _UnaryResult> && is_arithmetic_v<_Tp> &&
+ is_arithmetic_v<_UnaryResult>,
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__simd_transform_reduce(_DifferenceType __n, _Tp __init, _BinaryOperation, _UnaryOperation __f) noexcept {
+ _PSTL_PRAGMA_SIMD_REDUCTION(+ : __init)
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __init += __f(__i);
+ return __init;
+}
+
+template <typename _Backend,
+ typename _Size,
+ typename _Tp,
+ typename _BinaryOperation,
+ typename _UnaryOperation,
+ typename _UnaryResult = invoke_result_t<_UnaryOperation, _Size>,
+ __enable_if_t<!(__desugars_to_v<__plus_tag, _BinaryOperation, _Tp, _UnaryResult> && is_arithmetic_v<_Tp> &&
+ is_arithmetic_v<_UnaryResult>),
+ int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__simd_transform_reduce(_Size __n, _Tp __init, _BinaryOperation __binary_op, _UnaryOperation __f) noexcept {
+ constexpr size_t __lane_size = __cpu_traits<_Backend>::__lane_size;
+ const _Size __block_size = __lane_size / sizeof(_Tp);
+ if (__n > 2 * __block_size && __block_size > 1) {
+ alignas(__lane_size) char __lane_buffer[__lane_size];
+ _Tp* __lane = reinterpret_cast<_Tp*>(__lane_buffer);
+
+ // initializer
+ _PSTL_PRAGMA_SIMD
+ for (_Size __i = 0; __i < __block_size; ++__i) {
+ ::new (__lane + __i) _Tp(__binary_op(__f(__i), __f(__block_size + __i)));
+ }
+ // main loop
+ _Size __i = 2 * __block_size;
+ const _Size __last_iteration = __block_size * (__n / __block_size);
+ for (; __i < __last_iteration; __i += __block_size) {
+ _PSTL_PRAGMA_SIMD
+ for (_Size __j = 0; __j < __block_size; ++__j) {
+ __lane[__j] = __binary_op(std::move(__lane[__j]), __f(__i + __j));
+ }
+ }
+ // remainder
+ _PSTL_PRAGMA_SIMD
+ for (_Size __j = 0; __j < __n - __last_iteration; ++__j) {
+ __lane[__j] = __binary_op(std::move(__lane[__j]), __f(__last_iteration + __j));
+ }
+ // combiner
+ for (_Size __j = 0; __j < __block_size; ++__j) {
+ __init = __binary_op(std::move(__init), std::move(__lane[__j]));
+ }
+ // destroyer
+ _PSTL_PRAGMA_SIMD
+ for (_Size __j = 0; __j < __block_size; ++__j) {
+ __lane[__j].~_Tp();
+ }
+ } else {
+ for (_Size __i = 0; __i < __n; ++__i) {
+ __init = __binary_op(std::move(__init), __f(__i));
+ }
+ }
+ return __init;
+}
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_transform_reduce_binary {
+ template <class _Policy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _Tp,
+ class _BinaryOperation1,
+ class _BinaryOperation2>
+ _LIBCPP_HIDE_FROM_ABI optional<_Tp> operator()(
+ _Policy&& __policy,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _Tp __init,
+ _BinaryOperation1 __reduce,
+ _BinaryOperation2 __transform) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value) {
+ return __cpu_traits<_Backend>::__transform_reduce(
+ __first1,
+ std::move(__last1),
+ [__first1, __first2, __transform](_ForwardIterator1 __iter) {
+ return __transform(*__iter, *(__first2 + (__iter - __first1)));
+ },
+ std::move(__init),
+ std::move(__reduce),
+ [&__policy, __first1, __first2, __reduce, __transform](
+ _ForwardIterator1 __brick_first, _ForwardIterator1 __brick_last, _Tp __brick_init) {
+ using _TransformReduceBinaryUnseq =
+ __pstl::__transform_reduce_binary<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ return *_TransformReduceBinaryUnseq()(
+ std::__remove_parallel_policy(__policy),
+ __brick_first,
+ std::move(__brick_last),
+ __first2 + (__brick_first - __first1),
+ std::move(__brick_init),
+ std::move(__reduce),
+ std::move(__transform));
+ });
+ } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value) {
+ return __pstl::__simd_transform_reduce<_Backend>(
+ __last1 - __first1, std::move(__init), std::move(__reduce), [&](__iter_diff_t<_ForwardIterator1> __i) {
+ return __transform(__first1[__i], __first2[__i]);
+ });
+ } else {
+ return std::transform_reduce(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__init),
+ std::move(__reduce),
+ std::move(__transform));
+ }
+ }
+};
+
+template <class _Backend, class _RawExecutionPolicy>
+struct __cpu_parallel_transform_reduce {
+ template <class _Policy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI optional<_Tp>
+ operator()(_Policy&& __policy,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _Tp __init,
+ _BinaryOperation __reduce,
+ _UnaryOperation __transform) const noexcept {
+ if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return __cpu_traits<_Backend>::__transform_reduce(
+ std::move(__first),
+ std::move(__last),
+ [__transform](_ForwardIterator __iter) { return __transform(*__iter); },
+ std::move(__init),
+ __reduce,
+ [&__policy, __transform, __reduce](auto __brick_first, auto __brick_last, _Tp __brick_init) {
+ using _TransformReduceUnseq =
+ __pstl::__transform_reduce<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
+ auto __res = _TransformReduceUnseq()(
+ std::__remove_parallel_policy(__policy),
+ std::move(__brick_first),
+ std::move(__brick_last),
+ std::move(__brick_init),
+ std::move(__reduce),
+ std::move(__transform));
+ _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!");
+ return *std::move(__res);
+ });
+ } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return __pstl::__simd_transform_reduce<_Backend>(
+ __last - __first,
+ std::move(__init),
+ std::move(__reduce),
+ [=, &__transform](__iter_diff_t<_ForwardIterator> __i) { return __transform(__first[__i]); });
+ } else {
+ return std::transform_reduce(
+ std::move(__first), std::move(__last), std::move(__init), std::move(__reduce), std::move(__transform));
+ }
+ }
+};
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_CPU_ALGOS_TRANSFORM_REDUCE_H
diff --git a/libcxx/include/__cxx03/__pstl/dispatch.h b/libcxx/include/__cxx03/__pstl/dispatch.h
new file mode 100644
index 00000000000000..5e903f7524fe9b
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/dispatch.h
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_DISPATCH_H
+#define _LIBCPP___PSTL_DISPATCH_H
+
+#include <__config>
+#include <__pstl/backend_fwd.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/type_identity.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <template <class, class> class _Algorithm, class _Backend, class _ExecutionPolicy, class = void>
+constexpr bool __is_implemented_v = false;
+
+template <template <class, class> class _Algorithm, class _Backend, class _ExecutionPolicy>
+constexpr bool __is_implemented_v<_Algorithm,
+ _Backend,
+ _ExecutionPolicy,
+ __enable_if_t<sizeof(_Algorithm<_Backend, _ExecutionPolicy>)>> = true;
+
+// Helpful to provide better error messages. This will show the algorithm and the execution policy
+// in the compiler diagnostic.
+template <template <class, class> class _Algorithm, class _ExecutionPolicy>
+constexpr bool __cant_find_backend_for = false;
+
+template <template <class, class> class _Algorithm, class _BackendConfiguration, class _ExecutionPolicy>
+struct __find_first_implemented;
+
+template <template <class, class> class _Algorithm, class _ExecutionPolicy>
+struct __find_first_implemented<_Algorithm, __backend_configuration<>, _ExecutionPolicy> {
+ static_assert(__cant_find_backend_for<_Algorithm, _ExecutionPolicy>,
+ "Could not find a PSTL backend for the given algorithm and execution policy");
+};
+
+template <template <class, class> class _Algorithm, class _B1, class... _Bn, class _ExecutionPolicy>
+struct __find_first_implemented<_Algorithm, __backend_configuration<_B1, _Bn...>, _ExecutionPolicy>
+ : _If<__is_implemented_v<_Algorithm, _B1, _ExecutionPolicy>,
+ __type_identity<_Algorithm<_B1, _ExecutionPolicy>>,
+ __find_first_implemented<_Algorithm, __backend_configuration<_Bn...>, _ExecutionPolicy> > {};
+
+template <template <class, class> class _Algorithm, class _BackendConfiguration, class _ExecutionPolicy>
+using __dispatch = typename __find_first_implemented<_Algorithm, _BackendConfiguration, _ExecutionPolicy>::type;
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_DISPATCH_H
diff --git a/libcxx/include/__cxx03/__pstl/handle_exception.h b/libcxx/include/__cxx03/__pstl/handle_exception.h
new file mode 100644
index 00000000000000..d6270958c3a7c7
--- /dev/null
+++ b/libcxx/include/__cxx03/__pstl/handle_exception.h
@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___PSTL_HANDLE_EXCEPTION_H
+#define _LIBCPP___PSTL_HANDLE_EXCEPTION_H
+
+#include <__config>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <new> // __throw_bad_alloc
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __pstl {
+
+template <class _BackendFunction, class... _Args>
+_LIBCPP_HIDE_FROM_ABI auto __handle_exception_impl(_Args&&... __args) noexcept {
+ return _BackendFunction{}(std::forward<_Args>(__args)...);
+}
+
+// This function is used to call a backend PSTL algorithm from a frontend algorithm.
+//
+// All PSTL backend algorithms return an optional denoting whether there was an
+// "infrastructure"-level failure (aka failure to allocate). This function takes
+// care of unwrapping that and throwing `bad_alloc()` in case there was a problem
+// in the underlying implementation.
+//
+// We must also be careful not to call any user code that could throw an exception
+// (such as moving or copying iterators) in here since that should terminate the
+// program, which is why we delegate to a noexcept helper below.
+template <class _BackendFunction, class... _Args>
+_LIBCPP_HIDE_FROM_ABI auto __handle_exception(_Args&&... __args) {
+ auto __result = __pstl::__handle_exception_impl<_BackendFunction>(std::forward<_Args>(__args)...);
+ if (__result == nullopt)
+ std::__throw_bad_alloc();
+ else
+ return std::move(*__result);
+}
+
+} // namespace __pstl
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___PSTL_HANDLE_EXCEPTION_H
diff --git a/libcxx/include/__cxx03/__random/bernoulli_distribution.h b/libcxx/include/__cxx03/__random/bernoulli_distribution.h
new file mode 100644
index 00000000000000..4f33dca132d100
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/bernoulli_distribution.h
@@ -0,0 +1,123 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_BERNOULLI_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_BERNOULLI_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <iosfwd>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_TEMPLATE_VIS bernoulli_distribution {
+public:
+ // types
+ typedef bool result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ double __p_;
+
+ public:
+ typedef bernoulli_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(double __p = 0.5) : __p_(__p) {}
+
+ _LIBCPP_HIDE_FROM_ABI double p() const { return __p_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI bernoulli_distribution() : bernoulli_distribution(0.5) {}
+ _LIBCPP_HIDE_FROM_ABI explicit bernoulli_distribution(double __p) : __p_(param_type(__p)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit bernoulli_distribution(double __p = 0.5) : __p_(param_type(__p)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit bernoulli_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI double p() const { return __p_.p(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return false; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return true; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const bernoulli_distribution& __x, const bernoulli_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const bernoulli_distribution& __x, const bernoulli_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _URNG>
+inline bernoulli_distribution::result_type bernoulli_distribution::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ uniform_real_distribution<double> __gen;
+ return __gen(__g) < __p.p();
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const bernoulli_distribution& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ return __os << __x.p();
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, bernoulli_distribution& __x) {
+ typedef bernoulli_distribution _Eng;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ double __p;
+ __is >> __p;
+ if (!__is.fail())
+ __x.param(param_type(__p));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_BERNOULLI_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/binomial_distribution.h b/libcxx/include/__cxx03/__random/binomial_distribution.h
new file mode 100644
index 00000000000000..e8774bb8d67ee1
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/binomial_distribution.h
@@ -0,0 +1,198 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_BINOMIAL_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_BINOMIAL_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _IntType = int>
+class _LIBCPP_TEMPLATE_VIS binomial_distribution {
+ static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");
+
+public:
+ // types
+ typedef _IntType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __t_;
+ double __p_;
+ double __pr_;
+ double __odds_ratio_;
+ result_type __r0_;
+
+ public:
+ typedef binomial_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __t = 1, double __p = 0.5);
+
+ _LIBCPP_HIDE_FROM_ABI result_type t() const { return __t_; }
+ _LIBCPP_HIDE_FROM_ABI double p() const { return __p_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__t_ == __y.__t_ && __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+
+ friend class binomial_distribution;
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI binomial_distribution() : binomial_distribution(1) {}
+ _LIBCPP_HIDE_FROM_ABI explicit binomial_distribution(result_type __t, double __p = 0.5)
+ : __p_(param_type(__t, __p)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit binomial_distribution(result_type __t = 1, double __p = 0.5)
+ : __p_(param_type(__t, __p)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit binomial_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type t() const { return __p_.t(); }
+ _LIBCPP_HIDE_FROM_ABI double p() const { return __p_.p(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return t(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const binomial_distribution& __x, const binomial_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const binomial_distribution& __x, const binomial_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+#ifndef _LIBCPP_MSVCRT_LIKE
+extern "C" double lgamma_r(double, int*);
+#endif
+
+inline _LIBCPP_HIDE_FROM_ABI double __libcpp_lgamma(double __d) {
+#if defined(_LIBCPP_MSVCRT_LIKE)
+ return lgamma(__d);
+#else
+ int __sign;
+ return lgamma_r(__d, &__sign);
+#endif
+}
+
+template <class _IntType>
+binomial_distribution<_IntType>::param_type::param_type(result_type __t, double __p) : __t_(__t), __p_(__p) {
+ if (0 < __p_ && __p_ < 1) {
+ __r0_ = static_cast<result_type>((__t_ + 1) * __p_);
+ __pr_ = std::exp(
+ std::__libcpp_lgamma(__t_ + 1.) - std::__libcpp_lgamma(__r0_ + 1.) - std::__libcpp_lgamma(__t_ - __r0_ + 1.) +
+ __r0_ * std::log(__p_) + (__t_ - __r0_) * std::log(1 - __p_));
+ __odds_ratio_ = __p_ / (1 - __p_);
+ }
+}
+
+// Reference: Kemp, C.D. (1986). `A modal method for generating binomial
+// variables', Commun. Statist. - Theor. Meth. 15(3), 805-813.
+template <class _IntType>
+template <class _URNG>
+_IntType binomial_distribution<_IntType>::operator()(_URNG& __g, const param_type& __pr) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ if (__pr.__t_ == 0 || __pr.__p_ == 0)
+ return 0;
+ if (__pr.__p_ == 1)
+ return __pr.__t_;
+ uniform_real_distribution<double> __gen;
+ double __u = __gen(__g) - __pr.__pr_;
+ if (__u < 0)
+ return __pr.__r0_;
+ double __pu = __pr.__pr_;
+ double __pd = __pu;
+ result_type __ru = __pr.__r0_;
+ result_type __rd = __ru;
+ while (true) {
+ bool __break = true;
+ if (__rd >= 1) {
+ __pd *= __rd / (__pr.__odds_ratio_ * (__pr.__t_ - __rd + 1));
+ __u -= __pd;
+ __break = false;
+ if (__u < 0)
+ return __rd - 1;
+ }
+ if (__rd != 0)
+ --__rd;
+ ++__ru;
+ if (__ru <= __pr.__t_) {
+ __pu *= (__pr.__t_ - __ru + 1) * __pr.__odds_ratio_ / __ru;
+ __u -= __pu;
+ __break = false;
+ if (__u < 0)
+ return __ru;
+ }
+ if (__break)
+ return 0;
+ }
+}
+
+template <class _CharT, class _Traits, class _IntType>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const binomial_distribution<_IntType>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ return __os << __x.t() << __sp << __x.p();
+}
+
+template <class _CharT, class _Traits, class _IntType>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, binomial_distribution<_IntType>& __x) {
+ typedef binomial_distribution<_IntType> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __t;
+ double __p;
+ __is >> __t >> __p;
+ if (!__is.fail())
+ __x.param(param_type(__t, __p));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_BINOMIAL_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/cauchy_distribution.h b/libcxx/include/__cxx03/__random/cauchy_distribution.h
new file mode 100644
index 00000000000000..bd341427a1523a
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/cauchy_distribution.h
@@ -0,0 +1,139 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_CAUCHY_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_CAUCHY_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS cauchy_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __a_;
+ result_type __b_;
+
+ public:
+ typedef cauchy_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __a = 0, result_type __b = 1) : __a_(__a), __b_(__b) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __a_; }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __b_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI cauchy_distribution() : cauchy_distribution(0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit cauchy_distribution(result_type __a, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit cauchy_distribution(result_type __a = 0, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit cauchy_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __p_.a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return -numeric_limits<result_type>::infinity(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const cauchy_distribution& __x, const cauchy_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const cauchy_distribution& __x, const cauchy_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _RealType>
+template <class _URNG>
+inline _RealType cauchy_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ uniform_real_distribution<result_type> __gen;
+ // purposefully let tan arg get as close to pi/2 as it wants, tan will return a finite
+ return __p.a() + __p.b() * std::tan(3.1415926535897932384626433832795 * __gen(__g));
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const cauchy_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.a() << __sp << __x.b();
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, cauchy_distribution<_RT>& __x) {
+ typedef cauchy_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __a;
+ result_type __b;
+ __is >> __a >> __b;
+ if (!__is.fail())
+ __x.param(param_type(__a, __b));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_CAUCHY_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/chi_squared_distribution.h b/libcxx/include/__cxx03/__random/chi_squared_distribution.h
new file mode 100644
index 00000000000000..efa96dcdaafb5d
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/chi_squared_distribution.h
@@ -0,0 +1,125 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_CHI_SQUARED_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_CHI_SQUARED_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/gamma_distribution.h>
+#include <__random/is_valid.h>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS chi_squared_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __n_;
+
+ public:
+ typedef chi_squared_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __n = 1) : __n_(__n) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type n() const { return __n_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__n_ == __y.__n_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI chi_squared_distribution() : chi_squared_distribution(1) {}
+ _LIBCPP_HIDE_FROM_ABI explicit chi_squared_distribution(result_type __n) : __p_(param_type(__n)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit chi_squared_distribution(result_type __n = 1) : __p_(param_type(__n)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit chi_squared_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {
+ return gamma_distribution<result_type>(__p.n() / 2, 2)(__g);
+ }
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type n() const { return __p_.n(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const chi_squared_distribution& __x, const chi_squared_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const chi_squared_distribution& __x, const chi_squared_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const chi_squared_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ __os << __x.n();
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, chi_squared_distribution<_RT>& __x) {
+ typedef chi_squared_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __n;
+ __is >> __n;
+ if (!__is.fail())
+ __x.param(param_type(__n));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_CHI_SQUARED_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/clamp_to_integral.h b/libcxx/include/__cxx03/__random/clamp_to_integral.h
new file mode 100644
index 00000000000000..d9bfd31b7f012d
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/clamp_to_integral.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_CLAMP_TO_INTEGRAL_H
+#define _LIBCPP___RANDOM_CLAMP_TO_INTEGRAL_H
+
+#include <__config>
+#include <cmath>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _IntT,
+ class _FloatT,
+ bool _FloatBigger = (numeric_limits<_FloatT>::digits > numeric_limits<_IntT>::digits),
+ int _Bits = (numeric_limits<_IntT>::digits - numeric_limits<_FloatT>::digits)>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _IntT __max_representable_int_for_float() _NOEXCEPT {
+ static_assert(is_floating_point<_FloatT>::value, "must be a floating point type");
+ static_assert(is_integral<_IntT>::value, "must be an integral type");
+ static_assert(numeric_limits<_FloatT>::radix == 2, "FloatT has incorrect radix");
+ static_assert(
+ (_IsSame<_FloatT, float>::value || _IsSame<_FloatT, double>::value || _IsSame<_FloatT, long double>::value),
+ "unsupported floating point type");
+ return _FloatBigger ? numeric_limits<_IntT>::max() : (numeric_limits<_IntT>::max() >> _Bits << _Bits);
+}
+
+// Convert a floating point number to the specified integral type after
+// clamping to the integral type's representable range.
+//
+// The behavior is undefined if `__r` is NaN.
+template <class _IntT, class _RealT>
+_LIBCPP_HIDE_FROM_ABI _IntT __clamp_to_integral(_RealT __r) _NOEXCEPT {
+ using _Lim = numeric_limits<_IntT>;
+ const _IntT __max_val = __max_representable_int_for_float<_IntT, _RealT>();
+ if (__r >= ::nextafter(static_cast<_RealT>(__max_val), INFINITY)) {
+ return _Lim::max();
+ } else if (__r <= _Lim::lowest()) {
+ return _Lim::min();
+ }
+ return static_cast<_IntT>(__r);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_CLAMP_TO_INTEGRAL_H
diff --git a/libcxx/include/__cxx03/__random/default_random_engine.h b/libcxx/include/__cxx03/__random/default_random_engine.h
new file mode 100644
index 00000000000000..89792f4f0d43ea
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/default_random_engine.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_DEFAULT_RANDOM_ENGINE_H
+#define _LIBCPP___RANDOM_DEFAULT_RANDOM_ENGINE_H
+
+#include <__config>
+#include <__random/linear_congruential_engine.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+typedef minstd_rand default_random_engine;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANDOM_DEFAULT_RANDOM_ENGINE_H
diff --git a/libcxx/include/__cxx03/__random/discard_block_engine.h b/libcxx/include/__cxx03/__random/discard_block_engine.h
new file mode 100644
index 00000000000000..07f599067279e6
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/discard_block_engine.h
@@ -0,0 +1,172 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_DISCARD_BLOCK_ENGINE_H
+#define _LIBCPP___RANDOM_DISCARD_BLOCK_ENGINE_H
+
+#include <__config>
+#include <__random/is_seed_sequence.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_convertible.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Engine, size_t __p, size_t __r>
+class _LIBCPP_TEMPLATE_VIS discard_block_engine {
+ _Engine __e_;
+ int __n_;
+
+ static_assert(0 < __r, "discard_block_engine invalid parameters");
+ static_assert(__r <= __p, "discard_block_engine invalid parameters");
+#ifndef _LIBCPP_CXX03_LANG // numeric_limits::max() is not constexpr in C++03
+ static_assert(__r <= numeric_limits<int>::max(), "discard_block_engine invalid parameters");
+#endif
+
+public:
+ // types
+ typedef typename _Engine::result_type result_type;
+
+ // engine characteristics
+ static _LIBCPP_CONSTEXPR const size_t block_size = __p;
+ static _LIBCPP_CONSTEXPR const size_t used_block = __r;
+
+#ifdef _LIBCPP_CXX03_LANG
+ static const result_type _Min = _Engine::_Min;
+ static const result_type _Max = _Engine::_Max;
+#else
+ static constexpr result_type _Min = _Engine::min();
+ static constexpr result_type _Max = _Engine::max();
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Engine::min(); }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Engine::max(); }
+
+ // constructors and seeding functions
+ _LIBCPP_HIDE_FROM_ABI discard_block_engine() : __n_(0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit discard_block_engine(const _Engine& __e) : __e_(__e), __n_(0) {}
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI explicit discard_block_engine(_Engine&& __e) : __e_(std::move(__e)), __n_(0) {}
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI explicit discard_block_engine(result_type __sd) : __e_(__sd), __n_(0) {}
+ template <
+ class _Sseq,
+ __enable_if_t<__is_seed_sequence<_Sseq, discard_block_engine>::value && !is_convertible<_Sseq, _Engine>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit discard_block_engine(_Sseq& __q) : __e_(__q), __n_(0) {}
+ _LIBCPP_HIDE_FROM_ABI void seed() {
+ __e_.seed();
+ __n_ = 0;
+ }
+ _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd) {
+ __e_.seed(__sd);
+ __n_ = 0;
+ }
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, discard_block_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
+ __e_.seed(__q);
+ __n_ = 0;
+ }
+
+ // generating functions
+ _LIBCPP_HIDE_FROM_ABI result_type operator()();
+ _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
+ for (; __z; --__z)
+ operator()();
+ }
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI const _Engine& base() const _NOEXCEPT { return __e_; }
+
+ template <class _Eng, size_t _Pp, size_t _Rp>
+ friend bool
+ operator==(const discard_block_engine<_Eng, _Pp, _Rp>& __x, const discard_block_engine<_Eng, _Pp, _Rp>& __y);
+
+ template <class _Eng, size_t _Pp, size_t _Rp>
+ friend bool
+ operator!=(const discard_block_engine<_Eng, _Pp, _Rp>& __x, const discard_block_engine<_Eng, _Pp, _Rp>& __y);
+
+ template <class _CharT, class _Traits, class _Eng, size_t _Pp, size_t _Rp>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const discard_block_engine<_Eng, _Pp, _Rp>& __x);
+
+ template <class _CharT, class _Traits, class _Eng, size_t _Pp, size_t _Rp>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, discard_block_engine<_Eng, _Pp, _Rp>& __x);
+};
+
+template <class _Engine, size_t __p, size_t __r>
+_LIBCPP_CONSTEXPR const size_t discard_block_engine<_Engine, __p, __r>::block_size;
+
+template <class _Engine, size_t __p, size_t __r>
+_LIBCPP_CONSTEXPR const size_t discard_block_engine<_Engine, __p, __r>::used_block;
+
+template <class _Engine, size_t __p, size_t __r>
+typename discard_block_engine<_Engine, __p, __r>::result_type discard_block_engine<_Engine, __p, __r>::operator()() {
+ if (__n_ >= static_cast<int>(__r)) {
+ __e_.discard(__p - __r);
+ __n_ = 0;
+ }
+ ++__n_;
+ return __e_();
+}
+
+template <class _Eng, size_t _Pp, size_t _Rp>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const discard_block_engine<_Eng, _Pp, _Rp>& __x, const discard_block_engine<_Eng, _Pp, _Rp>& __y) {
+ return __x.__n_ == __y.__n_ && __x.__e_ == __y.__e_;
+}
+
+template <class _Eng, size_t _Pp, size_t _Rp>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const discard_block_engine<_Eng, _Pp, _Rp>& __x, const discard_block_engine<_Eng, _Pp, _Rp>& __y) {
+ return !(__x == __y);
+}
+
+template <class _CharT, class _Traits, class _Eng, size_t _Pp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const discard_block_engine<_Eng, _Pp, _Rp>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _Ostream;
+ __os.flags(_Ostream::dec | _Ostream::left);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ return __os << __x.__e_ << __sp << __x.__n_;
+}
+
+template <class _CharT, class _Traits, class _Eng, size_t _Pp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, discard_block_engine<_Eng, _Pp, _Rp>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ _Eng __e;
+ int __n;
+ __is >> __e >> __n;
+ if (!__is.fail()) {
+ __x.__e_ = __e;
+ __x.__n_ = __n;
+ }
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_DISCARD_BLOCK_ENGINE_H
diff --git a/libcxx/include/__cxx03/__random/discrete_distribution.h b/libcxx/include/__cxx03/__random/discrete_distribution.h
new file mode 100644
index 00000000000000..bb72dd6cb5074c
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/discrete_distribution.h
@@ -0,0 +1,212 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_DISCRETE_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_DISCRETE_DISTRIBUTION_H
+
+#include <__algorithm/upper_bound.h>
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cstddef>
+#include <iosfwd>
+#include <numeric>
+#include <vector>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _IntType = int>
+class _LIBCPP_TEMPLATE_VIS discrete_distribution {
+ static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");
+
+public:
+ // types
+ typedef _IntType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ vector<double> __p_;
+
+ public:
+ typedef discrete_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI param_type() {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI param_type(_InputIterator __f, _InputIterator __l) : __p_(__f, __l) {
+ __init();
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI param_type(initializer_list<double> __wl) : __p_(__wl.begin(), __wl.end()) { __init(); }
+#endif // _LIBCPP_CXX03_LANG
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI param_type(size_t __nw, double __xmin, double __xmax, _UnaryOperation __fw);
+
+ _LIBCPP_HIDE_FROM_ABI vector<double> probabilities() const;
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+
+ private:
+ _LIBCPP_HIDE_FROM_ABI void __init();
+
+ friend class discrete_distribution;
+
+ template <class _CharT, class _Traits, class _IT>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const discrete_distribution<_IT>& __x);
+
+ template <class _CharT, class _Traits, class _IT>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, discrete_distribution<_IT>& __x);
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+ _LIBCPP_HIDE_FROM_ABI discrete_distribution() {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI discrete_distribution(_InputIterator __f, _InputIterator __l) : __p_(__f, __l) {}
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI discrete_distribution(initializer_list<double> __wl) : __p_(__wl) {}
+#endif // _LIBCPP_CXX03_LANG
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI discrete_distribution(size_t __nw, double __xmin, double __xmax, _UnaryOperation __fw)
+ : __p_(__nw, __xmin, __xmax, __fw) {}
+ _LIBCPP_HIDE_FROM_ABI explicit discrete_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI vector<double> probabilities() const { return __p_.probabilities(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return __p_.__p_.size(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const discrete_distribution& __x, const discrete_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const discrete_distribution& __x, const discrete_distribution& __y) {
+ return !(__x == __y);
+ }
+
+ template <class _CharT, class _Traits, class _IT>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const discrete_distribution<_IT>& __x);
+
+ template <class _CharT, class _Traits, class _IT>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, discrete_distribution<_IT>& __x);
+};
+
+template <class _IntType>
+template <class _UnaryOperation>
+discrete_distribution<_IntType>::param_type::param_type(
+ size_t __nw, double __xmin, double __xmax, _UnaryOperation __fw) {
+ if (__nw > 1) {
+ __p_.reserve(__nw - 1);
+ double __d = (__xmax - __xmin) / __nw;
+ double __d2 = __d / 2;
+ for (size_t __k = 0; __k < __nw; ++__k)
+ __p_.push_back(__fw(__xmin + __k * __d + __d2));
+ __init();
+ }
+}
+
+template <class _IntType>
+void discrete_distribution<_IntType>::param_type::__init() {
+ if (!__p_.empty()) {
+ if (__p_.size() > 1) {
+ double __s = std::accumulate(__p_.begin(), __p_.end(), 0.0);
+ for (vector<double>::iterator __i = __p_.begin(), __e = __p_.end(); __i < __e; ++__i)
+ *__i /= __s;
+ vector<double> __t(__p_.size() - 1);
+ std::partial_sum(__p_.begin(), __p_.end() - 1, __t.begin());
+ swap(__p_, __t);
+ } else {
+ __p_.clear();
+ __p_.shrink_to_fit();
+ }
+ }
+}
+
+template <class _IntType>
+vector<double> discrete_distribution<_IntType>::param_type::probabilities() const {
+ size_t __n = __p_.size();
+ vector<double> __p(__n + 1);
+ std::adjacent_difference(__p_.begin(), __p_.end(), __p.begin());
+ if (__n > 0)
+ __p[__n] = 1 - __p_[__n - 1];
+ else
+ __p[0] = 1;
+ return __p;
+}
+
+template <class _IntType>
+template <class _URNG>
+_IntType discrete_distribution<_IntType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ uniform_real_distribution<double> __gen;
+ return static_cast<_IntType>(std::upper_bound(__p.__p_.begin(), __p.__p_.end(), __gen(__g)) - __p.__p_.begin());
+}
+
+template <class _CharT, class _Traits, class _IT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const discrete_distribution<_IT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ size_t __n = __x.__p_.__p_.size();
+ __os << __n;
+ for (size_t __i = 0; __i < __n; ++__i)
+ __os << __sp << __x.__p_.__p_[__i];
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _IT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, discrete_distribution<_IT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ size_t __n;
+ __is >> __n;
+ vector<double> __p(__n);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __is >> __p[__i];
+ if (!__is.fail())
+ swap(__x.__p_.__p_, __p);
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_DISCRETE_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/exponential_distribution.h b/libcxx/include/__cxx03/__random/exponential_distribution.h
new file mode 100644
index 00000000000000..e0e38841172f90
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/exponential_distribution.h
@@ -0,0 +1,132 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_EXPONENTIAL_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_EXPONENTIAL_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/generate_canonical.h>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS exponential_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __lambda_;
+
+ public:
+ typedef exponential_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __lambda = 1) : __lambda_(__lambda) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type lambda() const { return __lambda_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__lambda_ == __y.__lambda_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI exponential_distribution() : exponential_distribution(1) {}
+ _LIBCPP_HIDE_FROM_ABI explicit exponential_distribution(result_type __lambda) : __p_(param_type(__lambda)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit exponential_distribution(result_type __lambda = 1) : __p_(param_type(__lambda)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit exponential_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type lambda() const { return __p_.lambda(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const exponential_distribution& __x, const exponential_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const exponential_distribution& __x, const exponential_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _RealType>
+template <class _URNG>
+_RealType exponential_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ return -std::log(result_type(1) - std::generate_canonical<result_type, numeric_limits<result_type>::digits>(__g)) /
+ __p.lambda();
+}
+
+template <class _CharT, class _Traits, class _RealType>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const exponential_distribution<_RealType>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ return __os << __x.lambda();
+}
+
+template <class _CharT, class _Traits, class _RealType>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, exponential_distribution<_RealType>& __x) {
+ typedef exponential_distribution<_RealType> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __lambda;
+ __is >> __lambda;
+ if (!__is.fail())
+ __x.param(param_type(__lambda));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_EXPONENTIAL_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/extreme_value_distribution.h b/libcxx/include/__cxx03/__random/extreme_value_distribution.h
new file mode 100644
index 00000000000000..5505f93274f5c6
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/extreme_value_distribution.h
@@ -0,0 +1,139 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_EXTREME_VALUE_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_EXTREME_VALUE_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS extreme_value_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __a_;
+ result_type __b_;
+
+ public:
+ typedef extreme_value_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __a = 0, result_type __b = 1) : __a_(__a), __b_(__b) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __a_; }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __b_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI extreme_value_distribution() : extreme_value_distribution(0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit extreme_value_distribution(result_type __a, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit extreme_value_distribution(result_type __a = 0, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit extreme_value_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __p_.a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return -numeric_limits<result_type>::infinity(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const extreme_value_distribution& __x, const extreme_value_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const extreme_value_distribution& __x, const extreme_value_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _RealType>
+template <class _URNG>
+_RealType extreme_value_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ return __p.a() - __p.b() * std::log(-std::log(1 - uniform_real_distribution<result_type>()(__g)));
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const extreme_value_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.a() << __sp << __x.b();
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, extreme_value_distribution<_RT>& __x) {
+ typedef extreme_value_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __a;
+ result_type __b;
+ __is >> __a >> __b;
+ if (!__is.fail())
+ __x.param(param_type(__a, __b));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_EXTREME_VALUE_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/fisher_f_distribution.h b/libcxx/include/__cxx03/__random/fisher_f_distribution.h
new file mode 100644
index 00000000000000..cd170b3af388f2
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/fisher_f_distribution.h
@@ -0,0 +1,138 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_FISHER_F_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_FISHER_F_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/gamma_distribution.h>
+#include <__random/is_valid.h>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS fisher_f_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __m_;
+ result_type __n_;
+
+ public:
+ typedef fisher_f_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __m = 1, result_type __n = 1) : __m_(__m), __n_(__n) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type m() const { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI result_type n() const { return __n_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__m_ == __y.__m_ && __x.__n_ == __y.__n_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI fisher_f_distribution() : fisher_f_distribution(1) {}
+ _LIBCPP_HIDE_FROM_ABI explicit fisher_f_distribution(result_type __m, result_type __n = 1)
+ : __p_(param_type(__m, __n)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit fisher_f_distribution(result_type __m = 1, result_type __n = 1)
+ : __p_(param_type(__m, __n)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit fisher_f_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type m() const { return __p_.m(); }
+ _LIBCPP_HIDE_FROM_ABI result_type n() const { return __p_.n(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const fisher_f_distribution& __x, const fisher_f_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const fisher_f_distribution& __x, const fisher_f_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _RealType>
+template <class _URNG>
+_RealType fisher_f_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ gamma_distribution<result_type> __gdm(__p.m() * result_type(.5));
+ gamma_distribution<result_type> __gdn(__p.n() * result_type(.5));
+ return __p.n() * __gdm(__g) / (__p.m() * __gdn(__g));
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const fisher_f_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.m() << __sp << __x.n();
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, fisher_f_distribution<_RT>& __x) {
+ typedef fisher_f_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __m;
+ result_type __n;
+ __is >> __m >> __n;
+ if (!__is.fail())
+ __x.param(param_type(__m, __n));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_FISHER_F_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/gamma_distribution.h b/libcxx/include/__cxx03/__random/gamma_distribution.h
new file mode 100644
index 00000000000000..986e42c1c7f5ba
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/gamma_distribution.h
@@ -0,0 +1,181 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_GAMMA_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_GAMMA_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/exponential_distribution.h>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS gamma_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __alpha_;
+ result_type __beta_;
+
+ public:
+ typedef gamma_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __alpha = 1, result_type __beta = 1)
+ : __alpha_(__alpha), __beta_(__beta) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type alpha() const { return __alpha_; }
+ _LIBCPP_HIDE_FROM_ABI result_type beta() const { return __beta_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__alpha_ == __y.__alpha_ && __x.__beta_ == __y.__beta_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI gamma_distribution() : gamma_distribution(1) {}
+ _LIBCPP_HIDE_FROM_ABI explicit gamma_distribution(result_type __alpha, result_type __beta = 1)
+ : __p_(param_type(__alpha, __beta)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit gamma_distribution(result_type __alpha = 1, result_type __beta = 1)
+ : __p_(param_type(__alpha, __beta)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit gamma_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type alpha() const { return __p_.alpha(); }
+ _LIBCPP_HIDE_FROM_ABI result_type beta() const { return __p_.beta(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const gamma_distribution& __x, const gamma_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const gamma_distribution& __x, const gamma_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _RealType>
+template <class _URNG>
+_RealType gamma_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ result_type __a = __p.alpha();
+ uniform_real_distribution<result_type> __gen(0, 1);
+ exponential_distribution<result_type> __egen;
+ result_type __x;
+ if (__a == 1)
+ __x = __egen(__g);
+ else if (__a > 1) {
+ const result_type __b = __a - 1;
+ const result_type __c = 3 * __a - result_type(0.75);
+ while (true) {
+ const result_type __u = __gen(__g);
+ const result_type __v = __gen(__g);
+ const result_type __w = __u * (1 - __u);
+ if (__w != 0) {
+ const result_type __y = std::sqrt(__c / __w) * (__u - result_type(0.5));
+ __x = __b + __y;
+ if (__x >= 0) {
+ const result_type __z = 64 * __w * __w * __w * __v * __v;
+ if (__z <= 1 - 2 * __y * __y / __x)
+ break;
+ if (std::log(__z) <= 2 * (__b * std::log(__x / __b) - __y))
+ break;
+ }
+ }
+ }
+ } else // __a < 1
+ {
+ while (true) {
+ const result_type __u = __gen(__g);
+ const result_type __es = __egen(__g);
+ if (__u <= 1 - __a) {
+ __x = std::pow(__u, 1 / __a);
+ if (__x <= __es)
+ break;
+ } else {
+ const result_type __e = -std::log((1 - __u) / __a);
+ __x = std::pow(1 - __a + __a * __e, 1 / __a);
+ if (__x <= __e + __es)
+ break;
+ }
+ }
+ }
+ return __x * __p.beta();
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const gamma_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.alpha() << __sp << __x.beta();
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, gamma_distribution<_RT>& __x) {
+ typedef gamma_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __alpha;
+ result_type __beta;
+ __is >> __alpha >> __beta;
+ if (!__is.fail())
+ __x.param(param_type(__alpha, __beta));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_GAMMA_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/generate_canonical.h b/libcxx/include/__cxx03/__random/generate_canonical.h
new file mode 100644
index 00000000000000..738de1517e2867
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/generate_canonical.h
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_GENERATE_CANONICAL_H
+#define _LIBCPP___RANDOM_GENERATE_CANONICAL_H
+
+#include <__config>
+#include <__random/log2.h>
+#include <cstdint>
+#include <initializer_list>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// generate_canonical
+
+template <class _RealType, size_t __bits, class _URNG>
+_LIBCPP_HIDE_FROM_ABI _RealType generate_canonical(_URNG& __g) {
+ const size_t __dt = numeric_limits<_RealType>::digits;
+ const size_t __b = __dt < __bits ? __dt : __bits;
+#ifdef _LIBCPP_CXX03_LANG
+ const size_t __log_r = __log2<uint64_t, _URNG::_Max - _URNG::_Min + uint64_t(1)>::value;
+#else
+ const size_t __log_r = __log2<uint64_t, _URNG::max() - _URNG::min() + uint64_t(1)>::value;
+#endif
+ const size_t __k = __b / __log_r + (__b % __log_r != 0) + (__b == 0);
+ const _RealType __rp = static_cast<_RealType>(_URNG::max() - _URNG::min()) + _RealType(1);
+ _RealType __base = __rp;
+ _RealType __sp = __g() - _URNG::min();
+ for (size_t __i = 1; __i < __k; ++__i, __base *= __rp)
+ __sp += (__g() - _URNG::min()) * __base;
+ return __sp / __base;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_GENERATE_CANONICAL_H
diff --git a/libcxx/include/__cxx03/__random/geometric_distribution.h b/libcxx/include/__cxx03/__random/geometric_distribution.h
new file mode 100644
index 00000000000000..cecd7e57cfa641
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/geometric_distribution.h
@@ -0,0 +1,120 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_GEOMETRIC_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_GEOMETRIC_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/negative_binomial_distribution.h>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _IntType = int>
+class _LIBCPP_TEMPLATE_VIS geometric_distribution {
+ static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");
+
+public:
+ // types
+ typedef _IntType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ double __p_;
+
+ public:
+ typedef geometric_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(double __p = 0.5) : __p_(__p) {}
+
+ _LIBCPP_HIDE_FROM_ABI double p() const { return __p_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI geometric_distribution() : geometric_distribution(0.5) {}
+ _LIBCPP_HIDE_FROM_ABI explicit geometric_distribution(double __p) : __p_(__p) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit geometric_distribution(double __p = 0.5) : __p_(__p) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit geometric_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {
+ return negative_binomial_distribution<result_type>(1, __p.p())(__g);
+ }
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI double p() const { return __p_.p(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::max(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const geometric_distribution& __x, const geometric_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const geometric_distribution& __x, const geometric_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _CharT, class _Traits, class _IntType>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const geometric_distribution<_IntType>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ return __os << __x.p();
+}
+
+template <class _CharT, class _Traits, class _IntType>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, geometric_distribution<_IntType>& __x) {
+ typedef geometric_distribution<_IntType> _Eng;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ double __p;
+ __is >> __p;
+ if (!__is.fail())
+ __x.param(param_type(__p));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_GEOMETRIC_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/independent_bits_engine.h b/libcxx/include/__cxx03/__random/independent_bits_engine.h
new file mode 100644
index 00000000000000..0f4a7b82b98f89
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/independent_bits_engine.h
@@ -0,0 +1,205 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_INDEPENDENT_BITS_ENGINE_H
+#define _LIBCPP___RANDOM_INDEPENDENT_BITS_ENGINE_H
+
+#include <__config>
+#include <__fwd/istream.h>
+#include <__fwd/ostream.h>
+#include <__random/is_seed_sequence.h>
+#include <__random/log2.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_convertible.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Engine, size_t __w, class _UIntType>
+class _LIBCPP_TEMPLATE_VIS independent_bits_engine {
+ template <class _UInt, _UInt _R0, size_t _Wp, size_t _Mp>
+ class __get_n {
+ static _LIBCPP_CONSTEXPR const size_t _Dt = numeric_limits<_UInt>::digits;
+ static _LIBCPP_CONSTEXPR const size_t _Np = _Wp / _Mp + (_Wp % _Mp != 0);
+ static _LIBCPP_CONSTEXPR const size_t _W0 = _Wp / _Np;
+ static _LIBCPP_CONSTEXPR const _UInt _Y0 = _W0 >= _Dt ? 0 : (_R0 >> _W0) << _W0;
+
+ public:
+ static _LIBCPP_CONSTEXPR const size_t value = _R0 - _Y0 > _Y0 / _Np ? _Np + 1 : _Np;
+ };
+
+public:
+ // types
+ typedef _UIntType result_type;
+
+private:
+ _Engine __e_;
+
+ static _LIBCPP_CONSTEXPR const result_type _Dt = numeric_limits<result_type>::digits;
+ static_assert(0 < __w, "independent_bits_engine invalid parameters");
+ static_assert(__w <= _Dt, "independent_bits_engine invalid parameters");
+
+ typedef typename _Engine::result_type _Engine_result_type;
+ typedef __conditional_t<sizeof(_Engine_result_type) <= sizeof(result_type), result_type, _Engine_result_type>
+ _Working_result_type;
+#ifdef _LIBCPP_CXX03_LANG
+ static const _Working_result_type _Rp = _Engine::_Max - _Engine::_Min + _Working_result_type(1);
+#else
+ static _LIBCPP_CONSTEXPR const _Working_result_type _Rp = _Engine::max() - _Engine::min() + _Working_result_type(1);
+#endif
+ static _LIBCPP_CONSTEXPR const size_t __m = __log2<_Working_result_type, _Rp>::value;
+ static _LIBCPP_CONSTEXPR const size_t __n = __get_n<_Working_result_type, _Rp, __w, __m>::value;
+ static _LIBCPP_CONSTEXPR const size_t __w0 = __w / __n;
+ static _LIBCPP_CONSTEXPR const size_t __n0 = __n - __w % __n;
+ static _LIBCPP_CONSTEXPR const size_t _WDt = numeric_limits<_Working_result_type>::digits;
+ static _LIBCPP_CONSTEXPR const size_t _EDt = numeric_limits<_Engine_result_type>::digits;
+ static _LIBCPP_CONSTEXPR const _Working_result_type __y0 = __w0 >= _WDt ? 0 : (_Rp >> __w0) << __w0;
+ static _LIBCPP_CONSTEXPR const _Working_result_type __y1 = __w0 >= _WDt - 1 ? 0 : (_Rp >> (__w0 + 1)) << (__w0 + 1);
+ static _LIBCPP_CONSTEXPR const
+ _Engine_result_type __mask0 = __w0 > 0 ? _Engine_result_type(~0) >> (_EDt - __w0) : _Engine_result_type(0);
+ static _LIBCPP_CONSTEXPR const _Engine_result_type __mask1 =
+ __w0 < _EDt - 1 ? _Engine_result_type(~0) >> (_EDt - (__w0 + 1)) : _Engine_result_type(~0);
+
+public:
+ static _LIBCPP_CONSTEXPR const result_type _Min = 0;
+ static _LIBCPP_CONSTEXPR const result_type _Max =
+ __w == _Dt ? result_type(~0) : (result_type(1) << __w) - result_type(1);
+ static_assert(_Min < _Max, "independent_bits_engine invalid parameters");
+
+ // engine characteristics
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+
+ // constructors and seeding functions
+ _LIBCPP_HIDE_FROM_ABI independent_bits_engine() {}
+ _LIBCPP_HIDE_FROM_ABI explicit independent_bits_engine(const _Engine& __e) : __e_(__e) {}
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI explicit independent_bits_engine(_Engine&& __e) : __e_(std::move(__e)) {}
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI explicit independent_bits_engine(result_type __sd) : __e_(__sd) {}
+ template <
+ class _Sseq,
+ __enable_if_t<__is_seed_sequence<_Sseq, independent_bits_engine>::value && !is_convertible<_Sseq, _Engine>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit independent_bits_engine(_Sseq& __q) : __e_(__q) {}
+ _LIBCPP_HIDE_FROM_ABI void seed() { __e_.seed(); }
+ _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd) { __e_.seed(__sd); }
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, independent_bits_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
+ __e_.seed(__q);
+ }
+
+ // generating functions
+ _LIBCPP_HIDE_FROM_ABI result_type operator()() { return __eval(integral_constant<bool, _Rp != 0>()); }
+ _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
+ for (; __z; --__z)
+ operator()();
+ }
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI const _Engine& base() const _NOEXCEPT { return __e_; }
+
+ template <class _Eng, size_t _Wp, class _UInt>
+ friend bool operator==(const independent_bits_engine<_Eng, _Wp, _UInt>& __x,
+ const independent_bits_engine<_Eng, _Wp, _UInt>& __y);
+
+ template <class _Eng, size_t _Wp, class _UInt>
+ friend bool operator!=(const independent_bits_engine<_Eng, _Wp, _UInt>& __x,
+ const independent_bits_engine<_Eng, _Wp, _UInt>& __y);
+
+ template <class _CharT, class _Traits, class _Eng, size_t _Wp, class _UInt>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const independent_bits_engine<_Eng, _Wp, _UInt>& __x);
+
+ template <class _CharT, class _Traits, class _Eng, size_t _Wp, class _UInt>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, independent_bits_engine<_Eng, _Wp, _UInt>& __x);
+
+private:
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(false_type);
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(true_type);
+
+ template <size_t __count,
+ __enable_if_t<__count< _Dt, int> = 0> _LIBCPP_HIDE_FROM_ABI static result_type __lshift(result_type __x) {
+ return __x << __count;
+ }
+
+ template <size_t __count, __enable_if_t<(__count >= _Dt), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static result_type __lshift(result_type) {
+ return result_type(0);
+ }
+};
+
+template <class _Engine, size_t __w, class _UIntType>
+inline _UIntType independent_bits_engine<_Engine, __w, _UIntType>::__eval(false_type) {
+ return static_cast<result_type>(__e_() & __mask0);
+}
+
+template <class _Engine, size_t __w, class _UIntType>
+_UIntType independent_bits_engine<_Engine, __w, _UIntType>::__eval(true_type) {
+ result_type __sp = 0;
+ for (size_t __k = 0; __k < __n0; ++__k) {
+ _Engine_result_type __u;
+ do {
+ __u = __e_() - _Engine::min();
+ } while (__u >= __y0);
+ __sp = static_cast<result_type>(__lshift<__w0>(__sp) + (__u & __mask0));
+ }
+ for (size_t __k = __n0; __k < __n; ++__k) {
+ _Engine_result_type __u;
+ do {
+ __u = __e_() - _Engine::min();
+ } while (__u >= __y1);
+ __sp = static_cast<result_type>(__lshift<__w0 + 1>(__sp) + (__u & __mask1));
+ }
+ return __sp;
+}
+
+template <class _Eng, size_t _Wp, class _UInt>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const independent_bits_engine<_Eng, _Wp, _UInt>& __x, const independent_bits_engine<_Eng, _Wp, _UInt>& __y) {
+ return __x.base() == __y.base();
+}
+
+template <class _Eng, size_t _Wp, class _UInt>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const independent_bits_engine<_Eng, _Wp, _UInt>& __x, const independent_bits_engine<_Eng, _Wp, _UInt>& __y) {
+ return !(__x == __y);
+}
+
+template <class _CharT, class _Traits, class _Eng, size_t _Wp, class _UInt>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const independent_bits_engine<_Eng, _Wp, _UInt>& __x) {
+ return __os << __x.base();
+}
+
+template <class _CharT, class _Traits, class _Eng, size_t _Wp, class _UInt>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, independent_bits_engine<_Eng, _Wp, _UInt>& __x) {
+ _Eng __e;
+ __is >> __e;
+ if (!__is.fail())
+ __x.__e_ = __e;
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_INDEPENDENT_BITS_ENGINE_H
diff --git a/libcxx/include/__cxx03/__random/is_seed_sequence.h b/libcxx/include/__cxx03/__random/is_seed_sequence.h
new file mode 100644
index 00000000000000..c7171cff2eda09
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/is_seed_sequence.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_IS_SEED_SEQUENCE_H
+#define _LIBCPP___RANDOM_IS_SEED_SEQUENCE_H
+
+#include <__config>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Sseq, class _Engine>
+struct __is_seed_sequence {
+ static _LIBCPP_CONSTEXPR const bool value =
+ !is_convertible<_Sseq, typename _Engine::result_type>::value && !is_same<__remove_cv_t<_Sseq>, _Engine>::value;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANDOM_IS_SEED_SEQUENCE_H
diff --git a/libcxx/include/__cxx03/__random/is_valid.h b/libcxx/include/__cxx03/__random/is_valid.h
new file mode 100644
index 00000000000000..a3e0f143ae86a7
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/is_valid.h
@@ -0,0 +1,94 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_IS_VALID_H
+#define _LIBCPP___RANDOM_IS_VALID_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_unsigned.h>
+#include <__utility/declval.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// [rand.req.genl]/1.4:
+// The effect of instantiating a template that has a template type parameter
+// named RealType is undefined unless the corresponding template argument is
+// cv-unqualified and is one of float, double, or long double.
+
+template <class>
+struct __libcpp_random_is_valid_realtype : false_type {};
+template <>
+struct __libcpp_random_is_valid_realtype<float> : true_type {};
+template <>
+struct __libcpp_random_is_valid_realtype<double> : true_type {};
+template <>
+struct __libcpp_random_is_valid_realtype<long double> : true_type {};
+
+// [rand.req.genl]/1.5:
+// The effect of instantiating a template that has a template type parameter
+// named IntType is undefined unless the corresponding template argument is
+// cv-unqualified and is one of short, int, long, long long, unsigned short,
+// unsigned int, unsigned long, or unsigned long long.
+
+template <class>
+struct __libcpp_random_is_valid_inttype : false_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<int8_t> : true_type {}; // extension
+template <>
+struct __libcpp_random_is_valid_inttype<short> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<int> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<long> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<long long> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<uint8_t> : true_type {}; // extension
+template <>
+struct __libcpp_random_is_valid_inttype<unsigned short> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<unsigned int> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<unsigned long> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<unsigned long long> : true_type {};
+
+#ifndef _LIBCPP_HAS_NO_INT128
+template <>
+struct __libcpp_random_is_valid_inttype<__int128_t> : true_type {}; // extension
+template <>
+struct __libcpp_random_is_valid_inttype<__uint128_t> : true_type {}; // extension
+#endif // _LIBCPP_HAS_NO_INT128
+
+// [rand.req.urng]/3:
+// A class G meets the uniform random bit generator requirements if G models
+// uniform_random_bit_generator, invoke_result_t<G&> is an unsigned integer type,
+// and G provides a nested typedef-name result_type that denotes the same type
+// as invoke_result_t<G&>.
+// (In particular, reject URNGs with signed result_types; our distributions cannot
+// handle such generator types.)
+
+template <class, class = void>
+struct __libcpp_random_is_valid_urng : false_type {};
+template <class _Gp>
+struct __libcpp_random_is_valid_urng<
+ _Gp,
+ __enable_if_t< is_unsigned<typename _Gp::result_type>::value &&
+ _IsSame<decltype(std::declval<_Gp&>()()), typename _Gp::result_type>::value > > : true_type {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANDOM_IS_VALID_H
diff --git a/libcxx/include/__cxx03/__random/knuth_b.h b/libcxx/include/__cxx03/__random/knuth_b.h
new file mode 100644
index 00000000000000..f5b31cb64fa4ae
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/knuth_b.h
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_KNUTH_B_H
+#define _LIBCPP___RANDOM_KNUTH_B_H
+
+#include <__config>
+#include <__random/linear_congruential_engine.h>
+#include <__random/shuffle_order_engine.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+typedef shuffle_order_engine<minstd_rand0, 256> knuth_b;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANDOM_KNUTH_B_H
diff --git a/libcxx/include/__cxx03/__random/linear_congruential_engine.h b/libcxx/include/__cxx03/__random/linear_congruential_engine.h
new file mode 100644
index 00000000000000..9d77649e9cfc8e
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/linear_congruential_engine.h
@@ -0,0 +1,387 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_LINEAR_CONGRUENTIAL_ENGINE_H
+#define _LIBCPP___RANDOM_LINEAR_CONGRUENTIAL_ENGINE_H
+
+#include <__config>
+#include <__random/is_seed_sequence.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_unsigned.h>
+#include <cstdint>
+#include <iosfwd>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+enum __lce_alg_type {
+ _LCE_Full,
+ _LCE_Part,
+ _LCE_Schrage,
+ _LCE_Promote,
+};
+
+template <unsigned long long __a,
+ unsigned long long __c,
+ unsigned long long __m,
+ unsigned long long _Mp,
+ bool _HasOverflow = (__a != 0ull && (__m & (__m - 1ull)) != 0ull), // a != 0, m != 0, m != 2^n
+ bool _Full = (!_HasOverflow || __m - 1ull <= (_Mp - __c) / __a), // (a * x + c) % m works
+ bool _Part = (!_HasOverflow || __m - 1ull <= _Mp / __a), // (a * x) % m works
+ bool _Schrage = (_HasOverflow && __m % __a <= __m / __a)> // r <= q
+struct __lce_alg_picker {
+ static _LIBCPP_CONSTEXPR const __lce_alg_type __mode =
+ _Full ? _LCE_Full
+ : _Part ? _LCE_Part
+ : _Schrage ? _LCE_Schrage
+ : _LCE_Promote;
+
+#ifdef _LIBCPP_HAS_NO_INT128
+ static_assert(_Mp != (unsigned long long)(-1) || _Full || _Part || _Schrage,
+ "The current values for a, c, and m are not currently supported on platforms without __int128");
+#endif
+};
+
+template <unsigned long long __a,
+ unsigned long long __c,
+ unsigned long long __m,
+ unsigned long long _Mp,
+ __lce_alg_type _Mode = __lce_alg_picker<__a, __c, __m, _Mp>::__mode>
+struct __lce_ta;
+
+// 64
+
+#ifndef _LIBCPP_HAS_NO_INT128
+template <unsigned long long _Ap, unsigned long long _Cp, unsigned long long _Mp>
+struct __lce_ta<_Ap, _Cp, _Mp, (unsigned long long)(-1), _LCE_Promote> {
+ typedef unsigned long long result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __xp) {
+ __extension__ using __calc_type = unsigned __int128;
+ const __calc_type __a = static_cast<__calc_type>(_Ap);
+ const __calc_type __c = static_cast<__calc_type>(_Cp);
+ const __calc_type __m = static_cast<__calc_type>(_Mp);
+ const __calc_type __x = static_cast<__calc_type>(__xp);
+ return static_cast<result_type>((__a * __x + __c) % __m);
+ }
+};
+#endif
+
+template <unsigned long long __a, unsigned long long __c, unsigned long long __m>
+struct __lce_ta<__a, __c, __m, (unsigned long long)(-1), _LCE_Schrage> {
+ typedef unsigned long long result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ // Schrage's algorithm
+ const result_type __q = __m / __a;
+ const result_type __r = __m % __a;
+ const result_type __t0 = __a * (__x % __q);
+ const result_type __t1 = __r * (__x / __q);
+ __x = __t0 + (__t0 < __t1) * __m - __t1;
+ __x += __c - (__x >= __m - __c) * __m;
+ return __x;
+ }
+};
+
+template <unsigned long long __a, unsigned long long __m>
+struct __lce_ta<__a, 0ull, __m, (unsigned long long)(-1), _LCE_Schrage> {
+ typedef unsigned long long result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ // Schrage's algorithm
+ const result_type __q = __m / __a;
+ const result_type __r = __m % __a;
+ const result_type __t0 = __a * (__x % __q);
+ const result_type __t1 = __r * (__x / __q);
+ __x = __t0 + (__t0 < __t1) * __m - __t1;
+ return __x;
+ }
+};
+
+template <unsigned long long __a, unsigned long long __c, unsigned long long __m>
+struct __lce_ta<__a, __c, __m, (unsigned long long)(-1), _LCE_Part> {
+ typedef unsigned long long result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ // Use (((a*x) % m) + c) % m
+ __x = (__a * __x) % __m;
+ __x += __c - (__x >= __m - __c) * __m;
+ return __x;
+ }
+};
+
+template <unsigned long long __a, unsigned long long __c, unsigned long long __m>
+struct __lce_ta<__a, __c, __m, (unsigned long long)(-1), _LCE_Full> {
+ typedef unsigned long long result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) { return (__a * __x + __c) % __m; }
+};
+
+template <unsigned long long __a, unsigned long long __c>
+struct __lce_ta<__a, __c, 0ull, (unsigned long long)(-1), _LCE_Full> {
+ typedef unsigned long long result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) { return __a * __x + __c; }
+};
+
+// 32
+
+template <unsigned long long __a, unsigned long long __c, unsigned long long __m>
+struct __lce_ta<__a, __c, __m, unsigned(-1), _LCE_Promote> {
+ typedef unsigned result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ return static_cast<result_type>(__lce_ta<__a, __c, __m, (unsigned long long)(-1)>::next(__x));
+ }
+};
+
+template <unsigned long long _Ap, unsigned long long _Cp, unsigned long long _Mp>
+struct __lce_ta<_Ap, _Cp, _Mp, unsigned(-1), _LCE_Schrage> {
+ typedef unsigned result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ const result_type __a = static_cast<result_type>(_Ap);
+ const result_type __c = static_cast<result_type>(_Cp);
+ const result_type __m = static_cast<result_type>(_Mp);
+ // Schrage's algorithm
+ const result_type __q = __m / __a;
+ const result_type __r = __m % __a;
+ const result_type __t0 = __a * (__x % __q);
+ const result_type __t1 = __r * (__x / __q);
+ __x = __t0 + (__t0 < __t1) * __m - __t1;
+ __x += __c - (__x >= __m - __c) * __m;
+ return __x;
+ }
+};
+
+template <unsigned long long _Ap, unsigned long long _Mp>
+struct __lce_ta<_Ap, 0ull, _Mp, unsigned(-1), _LCE_Schrage> {
+ typedef unsigned result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ const result_type __a = static_cast<result_type>(_Ap);
+ const result_type __m = static_cast<result_type>(_Mp);
+ // Schrage's algorithm
+ const result_type __q = __m / __a;
+ const result_type __r = __m % __a;
+ const result_type __t0 = __a * (__x % __q);
+ const result_type __t1 = __r * (__x / __q);
+ __x = __t0 + (__t0 < __t1) * __m - __t1;
+ return __x;
+ }
+};
+
+template <unsigned long long _Ap, unsigned long long _Cp, unsigned long long _Mp>
+struct __lce_ta<_Ap, _Cp, _Mp, unsigned(-1), _LCE_Part> {
+ typedef unsigned result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ const result_type __a = static_cast<result_type>(_Ap);
+ const result_type __c = static_cast<result_type>(_Cp);
+ const result_type __m = static_cast<result_type>(_Mp);
+ // Use (((a*x) % m) + c) % m
+ __x = (__a * __x) % __m;
+ __x += __c - (__x >= __m - __c) * __m;
+ return __x;
+ }
+};
+
+template <unsigned long long _Ap, unsigned long long _Cp, unsigned long long _Mp>
+struct __lce_ta<_Ap, _Cp, _Mp, unsigned(-1), _LCE_Full> {
+ typedef unsigned result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ const result_type __a = static_cast<result_type>(_Ap);
+ const result_type __c = static_cast<result_type>(_Cp);
+ const result_type __m = static_cast<result_type>(_Mp);
+ return (__a * __x + __c) % __m;
+ }
+};
+
+template <unsigned long long _Ap, unsigned long long _Cp>
+struct __lce_ta<_Ap, _Cp, 0ull, unsigned(-1), _LCE_Full> {
+ typedef unsigned result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ const result_type __a = static_cast<result_type>(_Ap);
+ const result_type __c = static_cast<result_type>(_Cp);
+ return __a * __x + __c;
+ }
+};
+
+// 16
+
+template <unsigned long long __a, unsigned long long __c, unsigned long long __m, __lce_alg_type __mode>
+struct __lce_ta<__a, __c, __m, (unsigned short)(-1), __mode> {
+ typedef unsigned short result_type;
+ _LIBCPP_HIDE_FROM_ABI static result_type next(result_type __x) {
+ return static_cast<result_type>(__lce_ta<__a, __c, __m, unsigned(-1)>::next(__x));
+ }
+};
+
+template <class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+class _LIBCPP_TEMPLATE_VIS linear_congruential_engine;
+
+template <class _CharT, class _Traits, class _Up, _Up _Ap, _Up _Cp, _Up _Np>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const linear_congruential_engine<_Up, _Ap, _Cp, _Np>&);
+
+template <class _CharT, class _Traits, class _Up, _Up _Ap, _Up _Cp, _Up _Np>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, linear_congruential_engine<_Up, _Ap, _Cp, _Np>& __x);
+
+template <class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+class _LIBCPP_TEMPLATE_VIS linear_congruential_engine {
+public:
+ // types
+ typedef _UIntType result_type;
+
+private:
+ result_type __x_;
+
+ static _LIBCPP_CONSTEXPR const result_type _Mp = result_type(-1);
+
+ static_assert(__m == 0 || __a < __m, "linear_congruential_engine invalid parameters");
+ static_assert(__m == 0 || __c < __m, "linear_congruential_engine invalid parameters");
+ static_assert(is_unsigned<_UIntType>::value, "_UIntType must be unsigned type");
+
+public:
+ static _LIBCPP_CONSTEXPR const result_type _Min = __c == 0u ? 1u : 0u;
+ static _LIBCPP_CONSTEXPR const result_type _Max = __m - _UIntType(1u);
+ static_assert(_Min < _Max, "linear_congruential_engine invalid parameters");
+
+ // engine characteristics
+ static _LIBCPP_CONSTEXPR const result_type multiplier = __a;
+ static _LIBCPP_CONSTEXPR const result_type increment = __c;
+ static _LIBCPP_CONSTEXPR const result_type modulus = __m;
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+ static _LIBCPP_CONSTEXPR const result_type default_seed = 1u;
+
+ // constructors and seeding functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI linear_congruential_engine() : linear_congruential_engine(default_seed) {}
+ _LIBCPP_HIDE_FROM_ABI explicit linear_congruential_engine(result_type __s) { seed(__s); }
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit linear_congruential_engine(result_type __s = default_seed) { seed(__s); }
+#endif
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, linear_congruential_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit linear_congruential_engine(_Sseq& __q) {
+ seed(__q);
+ }
+ _LIBCPP_HIDE_FROM_ABI void seed(result_type __s = default_seed) {
+ seed(integral_constant<bool, __m == 0>(), integral_constant<bool, __c == 0>(), __s);
+ }
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, linear_congruential_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
+ __seed(
+ __q,
+ integral_constant<unsigned,
+ 1 + (__m == 0 ? (sizeof(result_type) * __CHAR_BIT__ - 1) / 32 : (__m > 0x100000000ull))>());
+ }
+
+ // generating functions
+ _LIBCPP_HIDE_FROM_ABI result_type operator()() {
+ return __x_ = static_cast<result_type>(__lce_ta<__a, __c, __m, _Mp>::next(__x_));
+ }
+ _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
+ for (; __z; --__z)
+ operator()();
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const linear_congruential_engine& __x, const linear_congruential_engine& __y) {
+ return __x.__x_ == __y.__x_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const linear_congruential_engine& __x, const linear_congruential_engine& __y) {
+ return !(__x == __y);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI void seed(true_type, true_type, result_type __s) { __x_ = __s == 0 ? 1 : __s; }
+ _LIBCPP_HIDE_FROM_ABI void seed(true_type, false_type, result_type __s) { __x_ = __s; }
+ _LIBCPP_HIDE_FROM_ABI void seed(false_type, true_type, result_type __s) { __x_ = __s % __m == 0 ? 1 : __s % __m; }
+ _LIBCPP_HIDE_FROM_ABI void seed(false_type, false_type, result_type __s) { __x_ = __s % __m; }
+
+ template <class _Sseq>
+ _LIBCPP_HIDE_FROM_ABI void __seed(_Sseq& __q, integral_constant<unsigned, 1>);
+ template <class _Sseq>
+ _LIBCPP_HIDE_FROM_ABI void __seed(_Sseq& __q, integral_constant<unsigned, 2>);
+
+ template <class _CharT, class _Traits, class _Up, _Up _Ap, _Up _Cp, _Up _Np>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const linear_congruential_engine<_Up, _Ap, _Cp, _Np>&);
+
+ template <class _CharT, class _Traits, class _Up, _Up _Ap, _Up _Cp, _Up _Np>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, linear_congruential_engine<_Up, _Ap, _Cp, _Np>& __x);
+};
+
+template <class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+_LIBCPP_CONSTEXPR const typename linear_congruential_engine<_UIntType, __a, __c, __m>::result_type
+ linear_congruential_engine<_UIntType, __a, __c, __m>::multiplier;
+
+template <class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+_LIBCPP_CONSTEXPR const typename linear_congruential_engine<_UIntType, __a, __c, __m>::result_type
+ linear_congruential_engine<_UIntType, __a, __c, __m>::increment;
+
+template <class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+_LIBCPP_CONSTEXPR const typename linear_congruential_engine<_UIntType, __a, __c, __m>::result_type
+ linear_congruential_engine<_UIntType, __a, __c, __m>::modulus;
+
+template <class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+_LIBCPP_CONSTEXPR const typename linear_congruential_engine<_UIntType, __a, __c, __m>::result_type
+ linear_congruential_engine<_UIntType, __a, __c, __m>::default_seed;
+
+template <class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+template <class _Sseq>
+void linear_congruential_engine<_UIntType, __a, __c, __m>::__seed(_Sseq& __q, integral_constant<unsigned, 1>) {
+ const unsigned __k = 1;
+ uint32_t __ar[__k + 3];
+ __q.generate(__ar, __ar + __k + 3);
+ result_type __s = static_cast<result_type>(__ar[3] % __m);
+ __x_ = __c == 0 && __s == 0 ? result_type(1) : __s;
+}
+
+template <class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+template <class _Sseq>
+void linear_congruential_engine<_UIntType, __a, __c, __m>::__seed(_Sseq& __q, integral_constant<unsigned, 2>) {
+ const unsigned __k = 2;
+ uint32_t __ar[__k + 3];
+ __q.generate(__ar, __ar + __k + 3);
+ result_type __s = static_cast<result_type>((__ar[3] + ((uint64_t)__ar[4] << 32)) % __m);
+ __x_ = __c == 0 && __s == 0 ? result_type(1) : __s;
+}
+
+template <class _CharT, class _Traits, class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const linear_congruential_engine<_UIntType, __a, __c, __m>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _Ostream;
+ __os.flags(_Ostream::dec | _Ostream::left);
+ __os.fill(__os.widen(' '));
+ return __os << __x.__x_;
+}
+
+template <class _CharT, class _Traits, class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, linear_congruential_engine<_UIntType, __a, __c, __m>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ _UIntType __t;
+ __is >> __t;
+ if (!__is.fail())
+ __x.__x_ = __t;
+ return __is;
+}
+
+typedef linear_congruential_engine<uint_fast32_t, 16807, 0, 2147483647> minstd_rand0;
+typedef linear_congruential_engine<uint_fast32_t, 48271, 0, 2147483647> minstd_rand;
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_LINEAR_CONGRUENTIAL_ENGINE_H
diff --git a/libcxx/include/__cxx03/__random/log2.h b/libcxx/include/__cxx03/__random/log2.h
new file mode 100644
index 00000000000000..74b4889c6402b5
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/log2.h
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_LOG2_H
+#define _LIBCPP___RANDOM_LOG2_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _UIntType, _UIntType _Xp, size_t _Rp>
+struct __log2_imp;
+
+template <unsigned long long _Xp, size_t _Rp>
+struct __log2_imp<unsigned long long, _Xp, _Rp> {
+ static const size_t value =
+ _Xp & ((unsigned long long)(1) << _Rp) ? _Rp : __log2_imp<unsigned long long, _Xp, _Rp - 1>::value;
+};
+
+template <unsigned long long _Xp>
+struct __log2_imp<unsigned long long, _Xp, 0> {
+ static const size_t value = 0;
+};
+
+template <size_t _Rp>
+struct __log2_imp<unsigned long long, 0, _Rp> {
+ static const size_t value = _Rp + 1;
+};
+
+#ifndef _LIBCPP_HAS_NO_INT128
+
+template <__uint128_t _Xp, size_t _Rp>
+struct __log2_imp<__uint128_t, _Xp, _Rp> {
+ static const size_t value =
+ (_Xp >> 64) ? (64 + __log2_imp<unsigned long long, (_Xp >> 64), 63>::value)
+ : __log2_imp<unsigned long long, _Xp, 63>::value;
+};
+
+#endif // _LIBCPP_HAS_NO_INT128
+
+template <class _UIntType, _UIntType _Xp>
+struct __log2 {
+ static const size_t value = __log2_imp<
+#ifndef _LIBCPP_HAS_NO_INT128
+ __conditional_t<sizeof(_UIntType) <= sizeof(unsigned long long), unsigned long long, __uint128_t>,
+#else
+ unsigned long long,
+#endif // _LIBCPP_HAS_NO_INT128
+ _Xp,
+ sizeof(_UIntType) * __CHAR_BIT__ - 1>::value;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANDOM_LOG2_H
diff --git a/libcxx/include/__cxx03/__random/lognormal_distribution.h b/libcxx/include/__cxx03/__random/lognormal_distribution.h
new file mode 100644
index 00000000000000..d8724f8bc5ceca
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/lognormal_distribution.h
@@ -0,0 +1,126 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_LOGNORMAL_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_LOGNORMAL_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/normal_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS lognormal_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __m_;
+ result_type __s_;
+
+ public:
+ typedef lognormal_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __m = 0, result_type __s = 1) : __m_(__m), __s_(__s) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type m() const { return __m_; }
+ _LIBCPP_HIDE_FROM_ABI result_type s() const { return __s_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__m_ == __y.__m_ && __x.__s_ == __y.__s_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ normal_distribution<result_type> __nd_;
+
+public:
+ // constructor and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI lognormal_distribution() : lognormal_distribution(0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit lognormal_distribution(result_type __m, result_type __s = 1) : __nd_(__m, __s) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit lognormal_distribution(result_type __m = 0, result_type __s = 1) : __nd_(__m, __s) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit lognormal_distribution(const param_type& __p) : __nd_(__p.m(), __p.s()) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() { __nd_.reset(); }
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return std::exp(__nd_(__g));
+ }
+
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {
+ typename normal_distribution<result_type>::param_type __pn(__p.m(), __p.s());
+ return std::exp(__nd_(__g, __pn));
+ }
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type m() const { return __nd_.mean(); }
+ _LIBCPP_HIDE_FROM_ABI result_type s() const { return __nd_.stddev(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return param_type(__nd_.mean(), __nd_.stddev()); }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) {
+ typename normal_distribution<result_type>::param_type __pn(__p.m(), __p.s());
+ __nd_.param(__pn);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const lognormal_distribution& __x, const lognormal_distribution& __y) {
+ return __x.__nd_ == __y.__nd_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const lognormal_distribution& __x, const lognormal_distribution& __y) {
+ return !(__x == __y);
+ }
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const lognormal_distribution<_RT>& __x);
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, lognormal_distribution<_RT>& __x);
+};
+
+template <class _CharT, class _Traits, class _RT>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const lognormal_distribution<_RT>& __x) {
+ return __os << __x.__nd_;
+}
+
+template <class _CharT, class _Traits, class _RT>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, lognormal_distribution<_RT>& __x) {
+ return __is >> __x.__nd_;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_LOGNORMAL_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/mersenne_twister_engine.h b/libcxx/include/__cxx03/__random/mersenne_twister_engine.h
new file mode 100644
index 00000000000000..65280d7c5505f7
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/mersenne_twister_engine.h
@@ -0,0 +1,914 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_MERSENNE_TWISTER_ENGINE_H
+#define _LIBCPP___RANDOM_MERSENNE_TWISTER_ENGINE_H
+
+#include <__algorithm/equal.h>
+#include <__algorithm/min.h>
+#include <__config>
+#include <__random/is_seed_sequence.h>
+#include <cstddef>
+#include <cstdint>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+class _LIBCPP_TEMPLATE_VIS mersenne_twister_engine;
+
+template <class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+_LIBCPP_HIDE_FROM_ABI bool
+operator==(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y);
+
+template <class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+_LIBCPP_HIDE_FROM_ABI bool
+operator!=(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y);
+
+template <class _CharT,
+ class _Traits,
+ class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
+
+template <class _CharT,
+ class _Traits,
+ class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is,
+ mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+class _LIBCPP_TEMPLATE_VIS mersenne_twister_engine {
+public:
+ // types
+ typedef _UIntType result_type;
+
+private:
+ result_type __x_[__n];
+ size_t __i_;
+
+ static_assert(0 < __m, "mersenne_twister_engine invalid parameters");
+ static_assert(__m <= __n, "mersenne_twister_engine invalid parameters");
+ static _LIBCPP_CONSTEXPR const result_type _Dt = numeric_limits<result_type>::digits;
+ static_assert(__w <= _Dt, "mersenne_twister_engine invalid parameters");
+ static_assert(2 <= __w, "mersenne_twister_engine invalid parameters");
+ static_assert(__r <= __w, "mersenne_twister_engine invalid parameters");
+ static_assert(__u <= __w, "mersenne_twister_engine invalid parameters");
+ static_assert(__s <= __w, "mersenne_twister_engine invalid parameters");
+ static_assert(__t <= __w, "mersenne_twister_engine invalid parameters");
+ static_assert(__l <= __w, "mersenne_twister_engine invalid parameters");
+
+public:
+ static _LIBCPP_CONSTEXPR const result_type _Min = 0;
+ static _LIBCPP_CONSTEXPR const result_type _Max =
+ __w == _Dt ? result_type(~0) : (result_type(1) << __w) - result_type(1);
+ static_assert(_Min < _Max, "mersenne_twister_engine invalid parameters");
+ static_assert(__a <= _Max, "mersenne_twister_engine invalid parameters");
+ static_assert(__b <= _Max, "mersenne_twister_engine invalid parameters");
+ static_assert(__c <= _Max, "mersenne_twister_engine invalid parameters");
+ static_assert(__d <= _Max, "mersenne_twister_engine invalid parameters");
+ static_assert(__f <= _Max, "mersenne_twister_engine invalid parameters");
+
+ // engine characteristics
+ static _LIBCPP_CONSTEXPR const size_t word_size = __w;
+ static _LIBCPP_CONSTEXPR const size_t state_size = __n;
+ static _LIBCPP_CONSTEXPR const size_t shift_size = __m;
+ static _LIBCPP_CONSTEXPR const size_t mask_bits = __r;
+ static _LIBCPP_CONSTEXPR const result_type xor_mask = __a;
+ static _LIBCPP_CONSTEXPR const size_t tempering_u = __u;
+ static _LIBCPP_CONSTEXPR const result_type tempering_d = __d;
+ static _LIBCPP_CONSTEXPR const size_t tempering_s = __s;
+ static _LIBCPP_CONSTEXPR const result_type tempering_b = __b;
+ static _LIBCPP_CONSTEXPR const size_t tempering_t = __t;
+ static _LIBCPP_CONSTEXPR const result_type tempering_c = __c;
+ static _LIBCPP_CONSTEXPR const size_t tempering_l = __l;
+ static _LIBCPP_CONSTEXPR const result_type initialization_multiplier = __f;
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+ static _LIBCPP_CONSTEXPR const result_type default_seed = 5489u;
+
+ // constructors and seeding functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI mersenne_twister_engine() : mersenne_twister_engine(default_seed) {}
+ _LIBCPP_HIDE_FROM_ABI explicit mersenne_twister_engine(result_type __sd) { seed(__sd); }
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit mersenne_twister_engine(result_type __sd = default_seed) { seed(__sd); }
+#endif
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, mersenne_twister_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit mersenne_twister_engine(_Sseq& __q) {
+ seed(__q);
+ }
+ _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd = default_seed);
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, mersenne_twister_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
+ __seed(__q, integral_constant<unsigned, 1 + (__w - 1) / 32>());
+ }
+
+ // generating functions
+ _LIBCPP_HIDE_FROM_ABI result_type operator()();
+ _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
+ for (; __z; --__z)
+ operator()();
+ }
+
+ template <class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+ friend bool operator==(
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y);
+
+ template <class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+ friend bool operator!=(
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y);
+
+ template <class _CharT,
+ class _Traits,
+ class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+ friend basic_ostream<_CharT, _Traits>& operator<<(
+ basic_ostream<_CharT, _Traits>& __os,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
+
+ template <class _CharT,
+ class _Traits,
+ class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is,
+ mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
+
+private:
+ template <class _Sseq>
+ _LIBCPP_HIDE_FROM_ABI void __seed(_Sseq& __q, integral_constant<unsigned, 1>);
+ template <class _Sseq>
+ _LIBCPP_HIDE_FROM_ABI void __seed(_Sseq& __q, integral_constant<unsigned, 2>);
+
+ template <size_t __count,
+ __enable_if_t<__count< __w, int> = 0> _LIBCPP_HIDE_FROM_ABI static result_type __lshift(result_type __x) {
+ return (__x << __count) & _Max;
+ }
+
+ template <size_t __count, __enable_if_t<(__count >= __w), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static result_type __lshift(result_type) {
+ return result_type(0);
+ }
+
+ template <size_t __count,
+ __enable_if_t<__count< _Dt, int> = 0> _LIBCPP_HIDE_FROM_ABI static result_type __rshift(result_type __x) {
+ return __x >> __count;
+ }
+
+ template <size_t __count, __enable_if_t<(__count >= _Dt), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static result_type __rshift(result_type) {
+ return result_type(0);
+ }
+};
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const size_t
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::word_size;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const size_t
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::state_size;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const size_t
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::shift_size;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const size_t
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::mask_bits;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const typename mersenne_twister_engine<
+ _UIntType,
+ __w,
+ __n,
+ __m,
+ __r,
+ __a,
+ __u,
+ __d,
+ __s,
+ __b,
+ __t,
+ __c,
+ __l,
+ __f>::result_type
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::xor_mask;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const size_t
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::tempering_u;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const typename mersenne_twister_engine<
+ _UIntType,
+ __w,
+ __n,
+ __m,
+ __r,
+ __a,
+ __u,
+ __d,
+ __s,
+ __b,
+ __t,
+ __c,
+ __l,
+ __f>::result_type
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::tempering_d;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const size_t
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::tempering_s;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const typename mersenne_twister_engine<
+ _UIntType,
+ __w,
+ __n,
+ __m,
+ __r,
+ __a,
+ __u,
+ __d,
+ __s,
+ __b,
+ __t,
+ __c,
+ __l,
+ __f>::result_type
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::tempering_b;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const size_t
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::tempering_t;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const typename mersenne_twister_engine<
+ _UIntType,
+ __w,
+ __n,
+ __m,
+ __r,
+ __a,
+ __u,
+ __d,
+ __s,
+ __b,
+ __t,
+ __c,
+ __l,
+ __f>::result_type
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::tempering_c;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const size_t
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::tempering_l;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const typename mersenne_twister_engine<
+ _UIntType,
+ __w,
+ __n,
+ __m,
+ __r,
+ __a,
+ __u,
+ __d,
+ __s,
+ __b,
+ __t,
+ __c,
+ __l,
+ __f>::result_type
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::
+ initialization_multiplier;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_LIBCPP_CONSTEXPR const typename mersenne_twister_engine<
+ _UIntType,
+ __w,
+ __n,
+ __m,
+ __r,
+ __a,
+ __u,
+ __d,
+ __s,
+ __b,
+ __t,
+ __c,
+ __l,
+ __f>::result_type
+ mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::default_seed;
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+void mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::seed(
+ result_type __sd) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK { // __w >= 2
+ __x_[0] = __sd & _Max;
+ for (size_t __i = 1; __i < __n; ++__i)
+ __x_[__i] = (__f * (__x_[__i - 1] ^ __rshift<__w - 2>(__x_[__i - 1])) + __i) & _Max;
+ __i_ = 0;
+}
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+template <class _Sseq>
+void mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::__seed(
+ _Sseq& __q, integral_constant<unsigned, 1>) {
+ const unsigned __k = 1;
+ uint32_t __ar[__n * __k];
+ __q.generate(__ar, __ar + __n * __k);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __x_[__i] = static_cast<result_type>(__ar[__i] & _Max);
+ const result_type __mask = __r == _Dt ? result_type(~0) : (result_type(1) << __r) - result_type(1);
+ __i_ = 0;
+ if ((__x_[0] & ~__mask) == 0) {
+ for (size_t __i = 1; __i < __n; ++__i)
+ if (__x_[__i] != 0)
+ return;
+ __x_[0] = result_type(1) << (__w - 1);
+ }
+}
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+template <class _Sseq>
+void mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::__seed(
+ _Sseq& __q, integral_constant<unsigned, 2>) {
+ const unsigned __k = 2;
+ uint32_t __ar[__n * __k];
+ __q.generate(__ar, __ar + __n * __k);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __x_[__i] = static_cast<result_type>((__ar[2 * __i] + ((uint64_t)__ar[2 * __i + 1] << 32)) & _Max);
+ const result_type __mask = __r == _Dt ? result_type(~0) : (result_type(1) << __r) - result_type(1);
+ __i_ = 0;
+ if ((__x_[0] & ~__mask) == 0) {
+ for (size_t __i = 1; __i < __n; ++__i)
+ if (__x_[__i] != 0)
+ return;
+ __x_[0] = result_type(1) << (__w - 1);
+ }
+}
+
+template <class _UIntType,
+ size_t __w,
+ size_t __n,
+ size_t __m,
+ size_t __r,
+ _UIntType __a,
+ size_t __u,
+ _UIntType __d,
+ size_t __s,
+ _UIntType __b,
+ size_t __t,
+ _UIntType __c,
+ size_t __l,
+ _UIntType __f>
+_UIntType
+mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>::operator()() {
+ const size_t __j = (__i_ + 1) % __n;
+ const result_type __mask = __r == _Dt ? result_type(~0) : (result_type(1) << __r) - result_type(1);
+ const result_type __yp = (__x_[__i_] & ~__mask) | (__x_[__j] & __mask);
+ const size_t __k = (__i_ + __m) % __n;
+ __x_[__i_] = __x_[__k] ^ __rshift<1>(__yp) ^ (__a * (__yp & 1));
+ result_type __z = __x_[__i_] ^ (__rshift<__u>(__x_[__i_]) & __d);
+ __i_ = __j;
+ __z ^= __lshift<__s>(__z) & __b;
+ __z ^= __lshift<__t>(__z) & __c;
+ return __z ^ __rshift<__l>(__z);
+}
+
+template <class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+_LIBCPP_HIDE_FROM_ABI bool
+operator==(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y) {
+ if (__x.__i_ == __y.__i_)
+ return std::equal(__x.__x_, __x.__x_ + _Np, __y.__x_);
+ if (__x.__i_ == 0 || __y.__i_ == 0) {
+ size_t __j = std::min(_Np - __x.__i_, _Np - __y.__i_);
+ if (!std::equal(__x.__x_ + __x.__i_, __x.__x_ + __x.__i_ + __j, __y.__x_ + __y.__i_))
+ return false;
+ if (__x.__i_ == 0)
+ return std::equal(__x.__x_ + __j, __x.__x_ + _Np, __y.__x_);
+ return std::equal(__x.__x_, __x.__x_ + (_Np - __j), __y.__x_ + __j);
+ }
+ if (__x.__i_ < __y.__i_) {
+ size_t __j = _Np - __y.__i_;
+ if (!std::equal(__x.__x_ + __x.__i_, __x.__x_ + (__x.__i_ + __j), __y.__x_ + __y.__i_))
+ return false;
+ if (!std::equal(__x.__x_ + (__x.__i_ + __j), __x.__x_ + _Np, __y.__x_))
+ return false;
+ return std::equal(__x.__x_, __x.__x_ + __x.__i_, __y.__x_ + (_Np - (__x.__i_ + __j)));
+ }
+ size_t __j = _Np - __x.__i_;
+ if (!std::equal(__y.__x_ + __y.__i_, __y.__x_ + (__y.__i_ + __j), __x.__x_ + __x.__i_))
+ return false;
+ if (!std::equal(__y.__x_ + (__y.__i_ + __j), __y.__x_ + _Np, __x.__x_))
+ return false;
+ return std::equal(__y.__x_, __y.__x_ + __y.__i_, __x.__x_ + (_Np - (__y.__i_ + __j)));
+}
+
+template <class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y) {
+ return !(__x == __y);
+}
+
+template <class _CharT,
+ class _Traits,
+ class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os,
+ const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _Ostream;
+ __os.flags(_Ostream::dec | _Ostream::left);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.__x_[__x.__i_];
+ for (size_t __j = __x.__i_ + 1; __j < _Np; ++__j)
+ __os << __sp << __x.__x_[__j];
+ for (size_t __j = 0; __j < __x.__i_; ++__j)
+ __os << __sp << __x.__x_[__j];
+ return __os;
+}
+
+template <class _CharT,
+ class _Traits,
+ class _UInt,
+ size_t _Wp,
+ size_t _Np,
+ size_t _Mp,
+ size_t _Rp,
+ _UInt _Ap,
+ size_t _Up,
+ _UInt _Dp,
+ size_t _Sp,
+ _UInt _Bp,
+ size_t _Tp,
+ _UInt _Cp,
+ size_t _Lp,
+ _UInt _Fp>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is,
+ mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ _UInt __t[_Np];
+ for (size_t __i = 0; __i < _Np; ++__i)
+ __is >> __t[__i];
+ if (!__is.fail()) {
+ for (size_t __i = 0; __i < _Np; ++__i)
+ __x.__x_[__i] = __t[__i];
+ __x.__i_ = 0;
+ }
+ return __is;
+}
+
+typedef mersenne_twister_engine<
+ uint_fast32_t,
+ 32,
+ 624,
+ 397,
+ 31,
+ 0x9908b0df,
+ 11,
+ 0xffffffff,
+ 7,
+ 0x9d2c5680,
+ 15,
+ 0xefc60000,
+ 18,
+ 1812433253>
+ mt19937;
+typedef mersenne_twister_engine<
+ uint_fast64_t,
+ 64,
+ 312,
+ 156,
+ 31,
+ 0xb5026f5aa96619e9ULL,
+ 29,
+ 0x5555555555555555ULL,
+ 17,
+ 0x71d67fffeda60000ULL,
+ 37,
+ 0xfff7eee000000000ULL,
+ 43,
+ 6364136223846793005ULL>
+ mt19937_64;
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_MERSENNE_TWISTER_ENGINE_H
diff --git a/libcxx/include/__cxx03/__random/negative_binomial_distribution.h b/libcxx/include/__cxx03/__random/negative_binomial_distribution.h
new file mode 100644
index 00000000000000..6d0055d01ed432
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/negative_binomial_distribution.h
@@ -0,0 +1,157 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_NEGATIVE_BINOMIAL_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_NEGATIVE_BINOMIAL_DISTRIBUTION_H
+
+#include <__assert>
+#include <__config>
+#include <__random/bernoulli_distribution.h>
+#include <__random/gamma_distribution.h>
+#include <__random/is_valid.h>
+#include <__random/poisson_distribution.h>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _IntType = int>
+class _LIBCPP_TEMPLATE_VIS negative_binomial_distribution {
+ static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");
+
+public:
+ // types
+ typedef _IntType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __k_;
+ double __p_;
+
+ public:
+ typedef negative_binomial_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __k = 1, double __p = 0.5) : __k_(__k), __p_(__p) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type k() const { return __k_; }
+ _LIBCPP_HIDE_FROM_ABI double p() const { return __p_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__k_ == __y.__k_ && __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI negative_binomial_distribution() : negative_binomial_distribution(1) {}
+ _LIBCPP_HIDE_FROM_ABI explicit negative_binomial_distribution(result_type __k, double __p = 0.5) : __p_(__k, __p) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit negative_binomial_distribution(result_type __k = 1, double __p = 0.5)
+ : __p_(__k, __p) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit negative_binomial_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type k() const { return __p_.k(); }
+ _LIBCPP_HIDE_FROM_ABI double p() const { return __p_.p(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::max(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const negative_binomial_distribution& __x, const negative_binomial_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const negative_binomial_distribution& __x, const negative_binomial_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _IntType>
+template <class _URNG>
+_IntType negative_binomial_distribution<_IntType>::operator()(_URNG& __urng, const param_type& __pr) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ result_type __k = __pr.k();
+ double __p = __pr.p();
+ // When the number of bits in _IntType is small, we are too likely to
+ // overflow __f below to use this technique.
+ if (__k <= 21 * __p && sizeof(_IntType) > 1) {
+ bernoulli_distribution __gen(__p);
+ result_type __f = 0;
+ result_type __s = 0;
+ while (__s < __k) {
+ if (__gen(__urng))
+ ++__s;
+ else
+ ++__f;
+ }
+ _LIBCPP_ASSERT_INTERNAL(__f >= 0,
+ "std::negative_binomial_distribution should never produce negative values. "
+ "This is almost certainly a signed integer overflow issue on __f.");
+ return __f;
+ }
+ return poisson_distribution<result_type>(gamma_distribution<double>(__k, (1 - __p) / __p)(__urng))(__urng);
+}
+
+template <class _CharT, class _Traits, class _IntType>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const negative_binomial_distribution<_IntType>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ return __os << __x.k() << __sp << __x.p();
+}
+
+template <class _CharT, class _Traits, class _IntType>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, negative_binomial_distribution<_IntType>& __x) {
+ typedef negative_binomial_distribution<_IntType> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __k;
+ double __p;
+ __is >> __k >> __p;
+ if (!__is.fail())
+ __x.param(param_type(__k, __p));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_NEGATIVE_BINOMIAL_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/normal_distribution.h b/libcxx/include/__cxx03/__random/normal_distribution.h
new file mode 100644
index 00000000000000..889f189e4161be
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/normal_distribution.h
@@ -0,0 +1,176 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_NORMAL_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_NORMAL_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS normal_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __mean_;
+ result_type __stddev_;
+
+ public:
+ typedef normal_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __mean = 0, result_type __stddev = 1)
+ : __mean_(__mean), __stddev_(__stddev) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type mean() const { return __mean_; }
+ _LIBCPP_HIDE_FROM_ABI result_type stddev() const { return __stddev_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__mean_ == __y.__mean_ && __x.__stddev_ == __y.__stddev_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+ result_type __v_;
+ bool __v_hot_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI normal_distribution() : normal_distribution(0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit normal_distribution(result_type __mean, result_type __stddev = 1)
+ : __p_(param_type(__mean, __stddev)), __v_hot_(false) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit normal_distribution(result_type __mean = 0, result_type __stddev = 1)
+ : __p_(param_type(__mean, __stddev)), __v_hot_(false) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit normal_distribution(const param_type& __p) : __p_(__p), __v_hot_(false) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() { __v_hot_ = false; }
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type mean() const { return __p_.mean(); }
+ _LIBCPP_HIDE_FROM_ABI result_type stddev() const { return __p_.stddev(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return -numeric_limits<result_type>::infinity(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const normal_distribution& __x, const normal_distribution& __y) {
+ return __x.__p_ == __y.__p_ && __x.__v_hot_ == __y.__v_hot_ && (!__x.__v_hot_ || __x.__v_ == __y.__v_);
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const normal_distribution& __x, const normal_distribution& __y) {
+ return !(__x == __y);
+ }
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const normal_distribution<_RT>& __x);
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, normal_distribution<_RT>& __x);
+};
+
+template <class _RealType>
+template <class _URNG>
+_RealType normal_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ result_type __up;
+ if (__v_hot_) {
+ __v_hot_ = false;
+ __up = __v_;
+ } else {
+ uniform_real_distribution<result_type> __uni(-1, 1);
+ result_type __u;
+ result_type __v;
+ result_type __s;
+ do {
+ __u = __uni(__g);
+ __v = __uni(__g);
+ __s = __u * __u + __v * __v;
+ } while (__s > 1 || __s == 0);
+ result_type __fp = std::sqrt(-2 * std::log(__s) / __s);
+ __v_ = __v * __fp;
+ __v_hot_ = true;
+ __up = __u * __fp;
+ }
+ return __up * __p.stddev() + __p.mean();
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const normal_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.mean() << __sp << __x.stddev() << __sp << __x.__v_hot_;
+ if (__x.__v_hot_)
+ __os << __sp << __x.__v_;
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, normal_distribution<_RT>& __x) {
+ typedef normal_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __mean;
+ result_type __stddev;
+ result_type __vp = 0;
+ bool __v_hot = false;
+ __is >> __mean >> __stddev >> __v_hot;
+ if (__v_hot)
+ __is >> __vp;
+ if (!__is.fail()) {
+ __x.param(param_type(__mean, __stddev));
+ __x.__v_hot_ = __v_hot;
+ __x.__v_ = __vp;
+ }
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_NORMAL_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/piecewise_constant_distribution.h b/libcxx/include/__cxx03/__random/piecewise_constant_distribution.h
new file mode 100644
index 00000000000000..e19380f97c35ec
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/piecewise_constant_distribution.h
@@ -0,0 +1,302 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_PIECEWISE_CONSTANT_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_PIECEWISE_CONSTANT_DISTRIBUTION_H
+
+#include <__algorithm/upper_bound.h>
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <iosfwd>
+#include <numeric>
+#include <vector>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS piecewise_constant_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ vector<result_type> __b_;
+ vector<result_type> __densities_;
+ vector<result_type> __areas_;
+
+ public:
+ typedef piecewise_constant_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI param_type();
+ template <class _InputIteratorB, class _InputIteratorW>
+ _LIBCPP_HIDE_FROM_ABI param_type(_InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w);
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI param_type(initializer_list<result_type> __bl, _UnaryOperation __fw);
+#endif // _LIBCPP_CXX03_LANG
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI param_type(size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw);
+ _LIBCPP_HIDE_FROM_ABI param_type(param_type const&) = default;
+ _LIBCPP_HIDE_FROM_ABI param_type& operator=(const param_type& __rhs);
+
+ _LIBCPP_HIDE_FROM_ABI vector<result_type> intervals() const { return __b_; }
+ _LIBCPP_HIDE_FROM_ABI vector<result_type> densities() const { return __densities_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__densities_ == __y.__densities_ && __x.__b_ == __y.__b_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+
+ private:
+ _LIBCPP_HIDE_FROM_ABI void __init();
+
+ friend class piecewise_constant_distribution;
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_constant_distribution<_RT>& __x);
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_constant_distribution<_RT>& __x);
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+ _LIBCPP_HIDE_FROM_ABI piecewise_constant_distribution() {}
+ template <class _InputIteratorB, class _InputIteratorW>
+ _LIBCPP_HIDE_FROM_ABI
+ piecewise_constant_distribution(_InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w)
+ : __p_(__f_b, __l_b, __f_w) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI piecewise_constant_distribution(initializer_list<result_type> __bl, _UnaryOperation __fw)
+ : __p_(__bl, __fw) {}
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI
+ piecewise_constant_distribution(size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw)
+ : __p_(__nw, __xmin, __xmax, __fw) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit piecewise_constant_distribution(const param_type& __p) : __p_(__p) {}
+
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI vector<result_type> intervals() const { return __p_.intervals(); }
+ _LIBCPP_HIDE_FROM_ABI vector<result_type> densities() const { return __p_.densities(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return __p_.__b_.front(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return __p_.__b_.back(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const piecewise_constant_distribution& __x, const piecewise_constant_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const piecewise_constant_distribution& __x, const piecewise_constant_distribution& __y) {
+ return !(__x == __y);
+ }
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_constant_distribution<_RT>& __x);
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_constant_distribution<_RT>& __x);
+};
+
+template <class _RealType>
+typename piecewise_constant_distribution<_RealType>::param_type&
+piecewise_constant_distribution<_RealType>::param_type::operator=(const param_type& __rhs) {
+ // These can throw
+ __b_.reserve(__rhs.__b_.size());
+ __densities_.reserve(__rhs.__densities_.size());
+ __areas_.reserve(__rhs.__areas_.size());
+
+ // These can not throw
+ __b_ = __rhs.__b_;
+ __densities_ = __rhs.__densities_;
+ __areas_ = __rhs.__areas_;
+ return *this;
+}
+
+template <class _RealType>
+void piecewise_constant_distribution<_RealType>::param_type::__init() {
+ // __densities_ contains non-normalized areas
+ result_type __total_area = std::accumulate(__densities_.begin(), __densities_.end(), result_type());
+ for (size_t __i = 0; __i < __densities_.size(); ++__i)
+ __densities_[__i] /= __total_area;
+ // __densities_ contains normalized areas
+ __areas_.assign(__densities_.size(), result_type());
+ std::partial_sum(__densities_.begin(), __densities_.end() - 1, __areas_.begin() + 1);
+ // __areas_ contains partial sums of normalized areas: [0, __densities_ - 1]
+ __densities_.back() = 1 - __areas_.back(); // correct round off error
+ for (size_t __i = 0; __i < __densities_.size(); ++__i)
+ __densities_[__i] /= (__b_[__i + 1] - __b_[__i]);
+ // __densities_ now contains __densities_
+}
+
+template <class _RealType>
+piecewise_constant_distribution<_RealType>::param_type::param_type() : __b_(2), __densities_(1, 1.0), __areas_(1, 0.0) {
+ __b_[1] = 1;
+}
+
+template <class _RealType>
+template <class _InputIteratorB, class _InputIteratorW>
+piecewise_constant_distribution<_RealType>::param_type::param_type(
+ _InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w)
+ : __b_(__f_b, __l_b) {
+ if (__b_.size() < 2) {
+ __b_.resize(2);
+ __b_[0] = 0;
+ __b_[1] = 1;
+ __densities_.assign(1, 1.0);
+ __areas_.assign(1, 0.0);
+ } else {
+ __densities_.reserve(__b_.size() - 1);
+ for (size_t __i = 0; __i < __b_.size() - 1; ++__i, ++__f_w)
+ __densities_.push_back(*__f_w);
+ __init();
+ }
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _RealType>
+template <class _UnaryOperation>
+piecewise_constant_distribution<_RealType>::param_type::param_type(
+ initializer_list<result_type> __bl, _UnaryOperation __fw)
+ : __b_(__bl.begin(), __bl.end()) {
+ if (__b_.size() < 2) {
+ __b_.resize(2);
+ __b_[0] = 0;
+ __b_[1] = 1;
+ __densities_.assign(1, 1.0);
+ __areas_.assign(1, 0.0);
+ } else {
+ __densities_.reserve(__b_.size() - 1);
+ for (size_t __i = 0; __i < __b_.size() - 1; ++__i)
+ __densities_.push_back(__fw((__b_[__i + 1] + __b_[__i]) * .5));
+ __init();
+ }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _RealType>
+template <class _UnaryOperation>
+piecewise_constant_distribution<_RealType>::param_type::param_type(
+ size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw)
+ : __b_(__nw == 0 ? 2 : __nw + 1) {
+ size_t __n = __b_.size() - 1;
+ result_type __d = (__xmax - __xmin) / __n;
+ __densities_.reserve(__n);
+ for (size_t __i = 0; __i < __n; ++__i) {
+ __b_[__i] = __xmin + __i * __d;
+ __densities_.push_back(__fw(__b_[__i] + __d * .5));
+ }
+ __b_[__n] = __xmax;
+ __init();
+}
+
+template <class _RealType>
+template <class _URNG>
+_RealType piecewise_constant_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ typedef uniform_real_distribution<result_type> _Gen;
+ result_type __u = _Gen()(__g);
+ ptrdiff_t __k = std::upper_bound(__p.__areas_.begin(), __p.__areas_.end(), __u) - __p.__areas_.begin() - 1;
+ return (__u - __p.__areas_[__k]) / __p.__densities_[__k] + __p.__b_[__k];
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_constant_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ size_t __n = __x.__p_.__b_.size();
+ __os << __n;
+ for (size_t __i = 0; __i < __n; ++__i)
+ __os << __sp << __x.__p_.__b_[__i];
+ __n = __x.__p_.__densities_.size();
+ __os << __sp << __n;
+ for (size_t __i = 0; __i < __n; ++__i)
+ __os << __sp << __x.__p_.__densities_[__i];
+ __n = __x.__p_.__areas_.size();
+ __os << __sp << __n;
+ for (size_t __i = 0; __i < __n; ++__i)
+ __os << __sp << __x.__p_.__areas_[__i];
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_constant_distribution<_RT>& __x) {
+ typedef piecewise_constant_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ size_t __n;
+ __is >> __n;
+ vector<result_type> __b(__n);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __is >> __b[__i];
+ __is >> __n;
+ vector<result_type> __densities(__n);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __is >> __densities[__i];
+ __is >> __n;
+ vector<result_type> __areas(__n);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __is >> __areas[__i];
+ if (!__is.fail()) {
+ swap(__x.__p_.__b_, __b);
+ swap(__x.__p_.__densities_, __densities);
+ swap(__x.__p_.__areas_, __areas);
+ }
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_PIECEWISE_CONSTANT_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/piecewise_linear_distribution.h b/libcxx/include/__cxx03/__random/piecewise_linear_distribution.h
new file mode 100644
index 00000000000000..43769dc825e65b
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/piecewise_linear_distribution.h
@@ -0,0 +1,315 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_PIECEWISE_LINEAR_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_PIECEWISE_LINEAR_DISTRIBUTION_H
+
+#include <__algorithm/upper_bound.h>
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <vector>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS piecewise_linear_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ vector<result_type> __b_;
+ vector<result_type> __densities_;
+ vector<result_type> __areas_;
+
+ public:
+ typedef piecewise_linear_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI param_type();
+ template <class _InputIteratorB, class _InputIteratorW>
+ _LIBCPP_HIDE_FROM_ABI param_type(_InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w);
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI param_type(initializer_list<result_type> __bl, _UnaryOperation __fw);
+#endif // _LIBCPP_CXX03_LANG
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI param_type(size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw);
+ _LIBCPP_HIDE_FROM_ABI param_type(param_type const&) = default;
+ _LIBCPP_HIDE_FROM_ABI param_type& operator=(const param_type& __rhs);
+
+ _LIBCPP_HIDE_FROM_ABI vector<result_type> intervals() const { return __b_; }
+ _LIBCPP_HIDE_FROM_ABI vector<result_type> densities() const { return __densities_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__densities_ == __y.__densities_ && __x.__b_ == __y.__b_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+
+ private:
+ _LIBCPP_HIDE_FROM_ABI void __init();
+
+ friend class piecewise_linear_distribution;
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_linear_distribution<_RT>& __x);
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_linear_distribution<_RT>& __x);
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+ _LIBCPP_HIDE_FROM_ABI piecewise_linear_distribution() {}
+ template <class _InputIteratorB, class _InputIteratorW>
+ _LIBCPP_HIDE_FROM_ABI
+ piecewise_linear_distribution(_InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w)
+ : __p_(__f_b, __l_b, __f_w) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI piecewise_linear_distribution(initializer_list<result_type> __bl, _UnaryOperation __fw)
+ : __p_(__bl, __fw) {}
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class _UnaryOperation>
+ _LIBCPP_HIDE_FROM_ABI
+ piecewise_linear_distribution(size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw)
+ : __p_(__nw, __xmin, __xmax, __fw) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit piecewise_linear_distribution(const param_type& __p) : __p_(__p) {}
+
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI vector<result_type> intervals() const { return __p_.intervals(); }
+ _LIBCPP_HIDE_FROM_ABI vector<result_type> densities() const { return __p_.densities(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return __p_.__b_.front(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return __p_.__b_.back(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const piecewise_linear_distribution& __x, const piecewise_linear_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const piecewise_linear_distribution& __x, const piecewise_linear_distribution& __y) {
+ return !(__x == __y);
+ }
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_linear_distribution<_RT>& __x);
+
+ template <class _CharT, class _Traits, class _RT>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_linear_distribution<_RT>& __x);
+};
+
+template <class _RealType>
+typename piecewise_linear_distribution<_RealType>::param_type&
+piecewise_linear_distribution<_RealType>::param_type::operator=(const param_type& __rhs) {
+ // These can throw
+ __b_.reserve(__rhs.__b_.size());
+ __densities_.reserve(__rhs.__densities_.size());
+ __areas_.reserve(__rhs.__areas_.size());
+
+ // These can not throw
+ __b_ = __rhs.__b_;
+ __densities_ = __rhs.__densities_;
+ __areas_ = __rhs.__areas_;
+ return *this;
+}
+
+template <class _RealType>
+void piecewise_linear_distribution<_RealType>::param_type::__init() {
+ __areas_.assign(__densities_.size() - 1, result_type());
+ result_type __sp = 0;
+ for (size_t __i = 0; __i < __areas_.size(); ++__i) {
+ __areas_[__i] = (__densities_[__i + 1] + __densities_[__i]) * (__b_[__i + 1] - __b_[__i]) * .5;
+ __sp += __areas_[__i];
+ }
+ for (size_t __i = __areas_.size(); __i > 1;) {
+ --__i;
+ __areas_[__i] = __areas_[__i - 1] / __sp;
+ }
+ __areas_[0] = 0;
+ for (size_t __i = 1; __i < __areas_.size(); ++__i)
+ __areas_[__i] += __areas_[__i - 1];
+ for (size_t __i = 0; __i < __densities_.size(); ++__i)
+ __densities_[__i] /= __sp;
+}
+
+template <class _RealType>
+piecewise_linear_distribution<_RealType>::param_type::param_type() : __b_(2), __densities_(2, 1.0), __areas_(1, 0.0) {
+ __b_[1] = 1;
+}
+
+template <class _RealType>
+template <class _InputIteratorB, class _InputIteratorW>
+piecewise_linear_distribution<_RealType>::param_type::param_type(
+ _InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w)
+ : __b_(__f_b, __l_b) {
+ if (__b_.size() < 2) {
+ __b_.resize(2);
+ __b_[0] = 0;
+ __b_[1] = 1;
+ __densities_.assign(2, 1.0);
+ __areas_.assign(1, 0.0);
+ } else {
+ __densities_.reserve(__b_.size());
+ for (size_t __i = 0; __i < __b_.size(); ++__i, ++__f_w)
+ __densities_.push_back(*__f_w);
+ __init();
+ }
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _RealType>
+template <class _UnaryOperation>
+piecewise_linear_distribution<_RealType>::param_type::param_type(
+ initializer_list<result_type> __bl, _UnaryOperation __fw)
+ : __b_(__bl.begin(), __bl.end()) {
+ if (__b_.size() < 2) {
+ __b_.resize(2);
+ __b_[0] = 0;
+ __b_[1] = 1;
+ __densities_.assign(2, 1.0);
+ __areas_.assign(1, 0.0);
+ } else {
+ __densities_.reserve(__b_.size());
+ for (size_t __i = 0; __i < __b_.size(); ++__i)
+ __densities_.push_back(__fw(__b_[__i]));
+ __init();
+ }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _RealType>
+template <class _UnaryOperation>
+piecewise_linear_distribution<_RealType>::param_type::param_type(
+ size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw)
+ : __b_(__nw == 0 ? 2 : __nw + 1) {
+ size_t __n = __b_.size() - 1;
+ result_type __d = (__xmax - __xmin) / __n;
+ __densities_.reserve(__b_.size());
+ for (size_t __i = 0; __i < __n; ++__i) {
+ __b_[__i] = __xmin + __i * __d;
+ __densities_.push_back(__fw(__b_[__i]));
+ }
+ __b_[__n] = __xmax;
+ __densities_.push_back(__fw(__b_[__n]));
+ __init();
+}
+
+template <class _RealType>
+template <class _URNG>
+_RealType piecewise_linear_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ typedef uniform_real_distribution<result_type> _Gen;
+ result_type __u = _Gen()(__g);
+ ptrdiff_t __k = std::upper_bound(__p.__areas_.begin(), __p.__areas_.end(), __u) - __p.__areas_.begin() - 1;
+ __u -= __p.__areas_[__k];
+ const result_type __dk = __p.__densities_[__k];
+ const result_type __dk1 = __p.__densities_[__k + 1];
+ const result_type __deltad = __dk1 - __dk;
+ const result_type __bk = __p.__b_[__k];
+ if (__deltad == 0)
+ return __u / __dk + __bk;
+ const result_type __bk1 = __p.__b_[__k + 1];
+ const result_type __deltab = __bk1 - __bk;
+ return (__bk * __dk1 - __bk1 * __dk + std::sqrt(__deltab * (__deltab * __dk * __dk + 2 * __deltad * __u))) / __deltad;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_linear_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ size_t __n = __x.__p_.__b_.size();
+ __os << __n;
+ for (size_t __i = 0; __i < __n; ++__i)
+ __os << __sp << __x.__p_.__b_[__i];
+ __n = __x.__p_.__densities_.size();
+ __os << __sp << __n;
+ for (size_t __i = 0; __i < __n; ++__i)
+ __os << __sp << __x.__p_.__densities_[__i];
+ __n = __x.__p_.__areas_.size();
+ __os << __sp << __n;
+ for (size_t __i = 0; __i < __n; ++__i)
+ __os << __sp << __x.__p_.__areas_[__i];
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_linear_distribution<_RT>& __x) {
+ typedef piecewise_linear_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ size_t __n;
+ __is >> __n;
+ vector<result_type> __b(__n);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __is >> __b[__i];
+ __is >> __n;
+ vector<result_type> __densities(__n);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __is >> __densities[__i];
+ __is >> __n;
+ vector<result_type> __areas(__n);
+ for (size_t __i = 0; __i < __n; ++__i)
+ __is >> __areas[__i];
+ if (!__is.fail()) {
+ swap(__x.__p_.__b_, __b);
+ swap(__x.__p_.__densities_, __densities);
+ swap(__x.__p_.__areas_, __areas);
+ }
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_PIECEWISE_LINEAR_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/poisson_distribution.h b/libcxx/include/__cxx03/__random/poisson_distribution.h
new file mode 100644
index 00000000000000..61a092ef9dd4dd
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/poisson_distribution.h
@@ -0,0 +1,241 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_POISSON_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_POISSON_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/clamp_to_integral.h>
+#include <__random/exponential_distribution.h>
+#include <__random/is_valid.h>
+#include <__random/normal_distribution.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _IntType = int>
+class _LIBCPP_TEMPLATE_VIS poisson_distribution {
+ static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");
+
+public:
+ // types
+ typedef _IntType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ double __mean_;
+ double __s_;
+ double __d_;
+ double __l_;
+ double __omega_;
+ double __c0_;
+ double __c1_;
+ double __c2_;
+ double __c3_;
+ double __c_;
+
+ public:
+ typedef poisson_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(double __mean = 1.0);
+
+ _LIBCPP_HIDE_FROM_ABI double mean() const { return __mean_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__mean_ == __y.__mean_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+
+ friend class poisson_distribution;
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI poisson_distribution() : poisson_distribution(1.0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit poisson_distribution(double __mean) : __p_(__mean) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit poisson_distribution(double __mean = 1.0) : __p_(__mean) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit poisson_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI double mean() const { return __p_.mean(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::max(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const poisson_distribution& __x, const poisson_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const poisson_distribution& __x, const poisson_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _IntType>
+poisson_distribution<_IntType>::param_type::param_type(double __mean)
+ // According to the standard `inf` is a valid input, but it causes the
+ // distribution to hang, so we replace it with the maximum representable
+ // mean.
+ : __mean_(isinf(__mean) ? numeric_limits<double>::max() : __mean) {
+ if (__mean_ < 10) {
+ __s_ = 0;
+ __d_ = 0;
+ __l_ = std::exp(-__mean_);
+ __omega_ = 0;
+ __c3_ = 0;
+ __c2_ = 0;
+ __c1_ = 0;
+ __c0_ = 0;
+ __c_ = 0;
+ } else {
+ __s_ = std::sqrt(__mean_);
+ __d_ = 6 * __mean_ * __mean_;
+ __l_ = std::trunc(__mean_ - 1.1484);
+ __omega_ = .3989423 / __s_;
+ double __b1 = .4166667E-1 / __mean_;
+ double __b2 = .3 * __b1 * __b1;
+ __c3_ = .1428571 * __b1 * __b2;
+ __c2_ = __b2 - 15. * __c3_;
+ __c1_ = __b1 - 6. * __b2 + 45. * __c3_;
+ __c0_ = 1. - __b1 + 3. * __b2 - 15. * __c3_;
+ __c_ = .1069 / __mean_;
+ }
+}
+
+template <class _IntType>
+template <class _URNG>
+_IntType poisson_distribution<_IntType>::operator()(_URNG& __urng, const param_type& __pr) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ double __tx;
+ uniform_real_distribution<double> __urd;
+ if (__pr.__mean_ < 10) {
+ __tx = 0;
+ for (double __p = __urd(__urng); __p > __pr.__l_; ++__tx)
+ __p *= __urd(__urng);
+ } else {
+ double __difmuk;
+ double __g = __pr.__mean_ + __pr.__s_ * normal_distribution<double>()(__urng);
+ double __u;
+ if (__g > 0) {
+ __tx = std::trunc(__g);
+ if (__tx >= __pr.__l_)
+ return std::__clamp_to_integral<result_type>(__tx);
+ __difmuk = __pr.__mean_ - __tx;
+ __u = __urd(__urng);
+ if (__pr.__d_ * __u >= __difmuk * __difmuk * __difmuk)
+ return std::__clamp_to_integral<result_type>(__tx);
+ }
+ exponential_distribution<double> __edist;
+ for (bool __using_exp_dist = false; true; __using_exp_dist = true) {
+ double __e;
+ if (__using_exp_dist || __g <= 0) {
+ double __t;
+ do {
+ __e = __edist(__urng);
+ __u = __urd(__urng);
+ __u += __u - 1;
+ __t = 1.8 + (__u < 0 ? -__e : __e);
+ } while (__t <= -.6744);
+ __tx = std::trunc(__pr.__mean_ + __pr.__s_ * __t);
+ __difmuk = __pr.__mean_ - __tx;
+ __using_exp_dist = true;
+ }
+ double __px;
+ double __py;
+ if (__tx < 10 && __tx >= 0) {
+ const double __fac[] = {1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880};
+ __px = -__pr.__mean_;
+ __py = std::pow(__pr.__mean_, (double)__tx) / __fac[static_cast<int>(__tx)];
+ } else {
+ double __del = .8333333E-1 / __tx;
+ __del -= 4.8 * __del * __del * __del;
+ double __v = __difmuk / __tx;
+ if (std::abs(__v) > 0.25)
+ __px = __tx * std::log(1 + __v) - __difmuk - __del;
+ else
+ __px = __tx * __v * __v *
+ (((((((.1250060 * __v + -.1384794) * __v + .1421878) * __v + -.1661269) * __v + .2000118) * __v +
+ -.2500068) *
+ __v +
+ .3333333) *
+ __v +
+ -.5) -
+ __del;
+ __py = .3989423 / std::sqrt(__tx);
+ }
+ double __r = (0.5 - __difmuk) / __pr.__s_;
+ double __r2 = __r * __r;
+ double __fx = -0.5 * __r2;
+ double __fy = __pr.__omega_ * (((__pr.__c3_ * __r2 + __pr.__c2_) * __r2 + __pr.__c1_) * __r2 + __pr.__c0_);
+ if (__using_exp_dist) {
+ if (__pr.__c_ * std::abs(__u) <= __py * std::exp(__px + __e) - __fy * std::exp(__fx + __e))
+ break;
+ } else {
+ if (__fy - __u * __fy <= __py * std::exp(__px - __fx))
+ break;
+ }
+ }
+ }
+ return std::__clamp_to_integral<result_type>(__tx);
+}
+
+template <class _CharT, class _Traits, class _IntType>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const poisson_distribution<_IntType>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ return __os << __x.mean();
+}
+
+template <class _CharT, class _Traits, class _IntType>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, poisson_distribution<_IntType>& __x) {
+ typedef poisson_distribution<_IntType> _Eng;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ double __mean;
+ __is >> __mean;
+ if (!__is.fail())
+ __x.param(param_type(__mean));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_POISSON_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/random_device.h b/libcxx/include/__cxx03/__random/random_device.h
new file mode 100644
index 00000000000000..52407943d2ec70
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/random_device.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_RANDOM_DEVICE_H
+#define _LIBCPP___RANDOM_RANDOM_DEVICE_H
+
+#include <__config>
+#include <string>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if !defined(_LIBCPP_HAS_NO_RANDOM_DEVICE)
+
+class _LIBCPP_EXPORTED_FROM_ABI random_device {
+# ifdef _LIBCPP_USING_DEV_RANDOM
+ int __f_;
+# elif !defined(_LIBCPP_ABI_NO_RANDOM_DEVICE_COMPATIBILITY_LAYOUT)
+ _LIBCPP_DIAGNOSTIC_PUSH
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wunused-private-field")
+
+ // Apple platforms used to use the `_LIBCPP_USING_DEV_RANDOM` code path, and now
+ // use `arc4random()` as of this comment. In order to avoid breaking the ABI, we
+ // retain the same layout as before.
+# if defined(__APPLE__)
+ int __padding_; // padding to fake the `__f_` field above
+# endif
+
+ // ... vendors can add workarounds here if they switch to a different representation ...
+
+ _LIBCPP_DIAGNOSTIC_POP
+# endif
+
+public:
+ // types
+ typedef unsigned result_type;
+
+ // generator characteristics
+ static _LIBCPP_CONSTEXPR const result_type _Min = 0;
+ static _LIBCPP_CONSTEXPR const result_type _Max = 0xFFFFFFFFu;
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+
+ // constructors
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI random_device() : random_device("/dev/urandom") {}
+ explicit random_device(const string& __token);
+# else
+ explicit random_device(const string& __token = "/dev/urandom");
+# endif
+ ~random_device();
+
+ // generating functions
+ result_type operator()();
+
+ // property functions
+ double entropy() const _NOEXCEPT;
+
+ random_device(const random_device&) = delete;
+ void operator=(const random_device&) = delete;
+};
+
+#endif // !_LIBCPP_HAS_NO_RANDOM_DEVICE
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_RANDOM_DEVICE_H
diff --git a/libcxx/include/__cxx03/__random/ranlux.h b/libcxx/include/__cxx03/__random/ranlux.h
new file mode 100644
index 00000000000000..952afde91b1094
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/ranlux.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_RANLUX_H
+#define _LIBCPP___RANDOM_RANLUX_H
+
+#include <__config>
+#include <__random/discard_block_engine.h>
+#include <__random/subtract_with_carry_engine.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+typedef subtract_with_carry_engine<uint_fast32_t, 24, 10, 24> ranlux24_base;
+typedef subtract_with_carry_engine<uint_fast64_t, 48, 5, 12> ranlux48_base;
+
+typedef discard_block_engine<ranlux24_base, 223, 23> ranlux24;
+typedef discard_block_engine<ranlux48_base, 389, 11> ranlux48;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANDOM_RANLUX_H
diff --git a/libcxx/include/__cxx03/__random/seed_seq.h b/libcxx/include/__cxx03/__random/seed_seq.h
new file mode 100644
index 00000000000000..5cf84aeb8a72b3
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/seed_seq.h
@@ -0,0 +1,166 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_SEED_SEQ_H
+#define _LIBCPP___RANDOM_SEED_SEQ_H
+
+#include <__algorithm/copy.h>
+#include <__algorithm/fill.h>
+#include <__algorithm/max.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_unsigned.h>
+#include <cstdint>
+#include <initializer_list>
+#include <vector>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_TEMPLATE_VIS seed_seq {
+public:
+ // types
+ typedef uint32_t result_type;
+
+ // constructors
+ _LIBCPP_HIDE_FROM_ABI seed_seq() _NOEXCEPT {}
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI seed_seq(initializer_list<_Tp> __il) {
+ __init(__il.begin(), __il.end());
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI seed_seq(_InputIterator __first, _InputIterator __last) {
+ static_assert(is_integral<typename iterator_traits<_InputIterator>::value_type>::value,
+ "Mandates: iterator_traits<InputIterator>::value_type is an integer type");
+ __init(__first, __last);
+ }
+
+ // generating functions
+ template <class _RandomAccessIterator>
+ _LIBCPP_HIDE_FROM_ABI void generate(_RandomAccessIterator __first, _RandomAccessIterator __last);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI size_t size() const _NOEXCEPT { return __v_.size(); }
+ template <class _OutputIterator>
+ _LIBCPP_HIDE_FROM_ABI void param(_OutputIterator __dest) const {
+ std::copy(__v_.begin(), __v_.end(), __dest);
+ }
+
+ seed_seq(const seed_seq&) = delete;
+ void operator=(const seed_seq&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI static result_type _Tp(result_type __x) { return __x ^ (__x >> 27); }
+
+private:
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void __init(_InputIterator __first, _InputIterator __last);
+
+ vector<result_type> __v_;
+};
+
+template <class _InputIterator>
+void seed_seq::__init(_InputIterator __first, _InputIterator __last) {
+ for (_InputIterator __s = __first; __s != __last; ++__s)
+ __v_.push_back(*__s & 0xFFFFFFFF);
+}
+
+template <class _RandomAccessIterator>
+void seed_seq::generate(_RandomAccessIterator __first, _RandomAccessIterator __last) {
+ using _ValueType = typename iterator_traits<_RandomAccessIterator>::value_type;
+ static_assert(is_unsigned<_ValueType>::value && sizeof(_ValueType) >= sizeof(uint32_t),
+ "[rand.util.seedseq]/7 requires the value_type of the iterator to be an unsigned "
+ "integer capable of accommodating 32-bit quantities.");
+
+ if (__first != __last) {
+ std::fill(__first, __last, 0x8b8b8b8b);
+ const size_t __n = static_cast<size_t>(__last - __first);
+ const size_t __s = __v_.size();
+ const size_t __t = (__n >= 623) ? 11 : (__n >= 68) ? 7 : (__n >= 39) ? 5 : (__n >= 7) ? 3 : (__n - 1) / 2;
+ const size_t __p = (__n - __t) / 2;
+ const size_t __q = __p + __t;
+ const size_t __m = std::max(__s + 1, __n);
+ // __k = 0;
+ {
+ result_type __r = 1664525 * _Tp(__first[0] ^ __first[__p] ^ __first[__n - 1]);
+ __first[__p] += __r;
+ __r += __s;
+ __first[__q] += __r;
+ __first[0] = __r;
+ }
+ // Initialize indexing terms used with if statements as an optimization to
+ // avoid calculating modulo n on every loop iteration for each term.
+ size_t __kmodn = 0; // __k % __n
+ size_t __k1modn = __n - 1; // (__k - 1) % __n
+ size_t __kpmodn = __p % __n; // (__k + __p) % __n
+ size_t __kqmodn = __q % __n; // (__k + __q) % __n
+
+ for (size_t __k = 1; __k <= __s; ++__k) {
+ if (++__kmodn == __n)
+ __kmodn = 0;
+ if (++__k1modn == __n)
+ __k1modn = 0;
+ if (++__kpmodn == __n)
+ __kpmodn = 0;
+ if (++__kqmodn == __n)
+ __kqmodn = 0;
+
+ result_type __r = 1664525 * _Tp(__first[__kmodn] ^ __first[__kpmodn] ^ __first[__k1modn]);
+ __first[__kpmodn] += __r;
+ __r += __kmodn + __v_[__k - 1];
+ __first[__kqmodn] += __r;
+ __first[__kmodn] = __r;
+ }
+ for (size_t __k = __s + 1; __k < __m; ++__k) {
+ if (++__kmodn == __n)
+ __kmodn = 0;
+ if (++__k1modn == __n)
+ __k1modn = 0;
+ if (++__kpmodn == __n)
+ __kpmodn = 0;
+ if (++__kqmodn == __n)
+ __kqmodn = 0;
+
+ result_type __r = 1664525 * _Tp(__first[__kmodn] ^ __first[__kpmodn] ^ __first[__k1modn]);
+ __first[__kpmodn] += __r;
+ __r += __kmodn;
+ __first[__kqmodn] += __r;
+ __first[__kmodn] = __r;
+ }
+ for (size_t __k = __m; __k < __m + __n; ++__k) {
+ if (++__kmodn == __n)
+ __kmodn = 0;
+ if (++__k1modn == __n)
+ __k1modn = 0;
+ if (++__kpmodn == __n)
+ __kpmodn = 0;
+ if (++__kqmodn == __n)
+ __kqmodn = 0;
+
+ result_type __r = 1566083941 * _Tp(__first[__kmodn] + __first[__kpmodn] + __first[__k1modn]);
+ __first[__kpmodn] ^= __r;
+ __r -= __kmodn;
+ __first[__kqmodn] ^= __r;
+ __first[__kmodn] = __r;
+ }
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_SEED_SEQ_H
diff --git a/libcxx/include/__cxx03/__random/shuffle_order_engine.h b/libcxx/include/__cxx03/__random/shuffle_order_engine.h
new file mode 100644
index 00000000000000..f54ed17e38383a
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/shuffle_order_engine.h
@@ -0,0 +1,230 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_SHUFFLE_ORDER_ENGINE_H
+#define _LIBCPP___RANDOM_SHUFFLE_ORDER_ENGINE_H
+
+#include <__algorithm/equal.h>
+#include <__config>
+#include <__random/is_seed_sequence.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_convertible.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <cstdint>
+#include <iosfwd>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <uint64_t _Xp, uint64_t _Yp>
+struct __ugcd {
+ static _LIBCPP_CONSTEXPR const uint64_t value = __ugcd<_Yp, _Xp % _Yp>::value;
+};
+
+template <uint64_t _Xp>
+struct __ugcd<_Xp, 0> {
+ static _LIBCPP_CONSTEXPR const uint64_t value = _Xp;
+};
+
+template <uint64_t _Np, uint64_t _Dp>
+class __uratio {
+ static_assert(_Dp != 0, "__uratio divide by 0");
+ static _LIBCPP_CONSTEXPR const uint64_t __gcd = __ugcd<_Np, _Dp>::value;
+
+public:
+ static _LIBCPP_CONSTEXPR const uint64_t num = _Np / __gcd;
+ static _LIBCPP_CONSTEXPR const uint64_t den = _Dp / __gcd;
+
+ typedef __uratio<num, den> type;
+};
+
+template <class _Engine, size_t __k>
+class _LIBCPP_TEMPLATE_VIS shuffle_order_engine {
+ static_assert(0 < __k, "shuffle_order_engine invalid parameters");
+
+public:
+ // types
+ typedef typename _Engine::result_type result_type;
+
+private:
+ _Engine __e_;
+ result_type __v_[__k];
+ result_type __y_;
+
+public:
+ // engine characteristics
+ static _LIBCPP_CONSTEXPR const size_t table_size = __k;
+
+#ifdef _LIBCPP_CXX03_LANG
+ static const result_type _Min = _Engine::_Min;
+ static const result_type _Max = _Engine::_Max;
+#else
+ static _LIBCPP_CONSTEXPR const result_type _Min = _Engine::min();
+ static _LIBCPP_CONSTEXPR const result_type _Max = _Engine::max();
+#endif
+ static_assert(_Min < _Max, "shuffle_order_engine invalid parameters");
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+
+ static _LIBCPP_CONSTEXPR const unsigned long long _Rp = _Max - _Min + 1ull;
+
+ // constructors and seeding functions
+ _LIBCPP_HIDE_FROM_ABI shuffle_order_engine() { __init(); }
+ _LIBCPP_HIDE_FROM_ABI explicit shuffle_order_engine(const _Engine& __e) : __e_(__e) { __init(); }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI explicit shuffle_order_engine(_Engine&& __e) : __e_(std::move(__e)) { __init(); }
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI explicit shuffle_order_engine(result_type __sd) : __e_(__sd) { __init(); }
+ template <
+ class _Sseq,
+ __enable_if_t<__is_seed_sequence<_Sseq, shuffle_order_engine>::value && !is_convertible<_Sseq, _Engine>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit shuffle_order_engine(_Sseq& __q) : __e_(__q) {
+ __init();
+ }
+ _LIBCPP_HIDE_FROM_ABI void seed() {
+ __e_.seed();
+ __init();
+ }
+ _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd) {
+ __e_.seed(__sd);
+ __init();
+ }
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, shuffle_order_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
+ __e_.seed(__q);
+ __init();
+ }
+
+ // generating functions
+ _LIBCPP_HIDE_FROM_ABI result_type operator()() { return __eval(integral_constant<bool, _Rp != 0>()); }
+ _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
+ for (; __z; --__z)
+ operator()();
+ }
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI const _Engine& base() const _NOEXCEPT { return __e_; }
+
+private:
+ template <class _Eng, size_t _Kp>
+ friend bool operator==(const shuffle_order_engine<_Eng, _Kp>& __x, const shuffle_order_engine<_Eng, _Kp>& __y);
+
+ template <class _Eng, size_t _Kp>
+ friend bool operator!=(const shuffle_order_engine<_Eng, _Kp>& __x, const shuffle_order_engine<_Eng, _Kp>& __y);
+
+ template <class _CharT, class _Traits, class _Eng, size_t _Kp>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const shuffle_order_engine<_Eng, _Kp>& __x);
+
+ template <class _CharT, class _Traits, class _Eng, size_t _Kp>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, shuffle_order_engine<_Eng, _Kp>& __x);
+
+ _LIBCPP_HIDE_FROM_ABI void __init() {
+ for (size_t __i = 0; __i < __k; ++__i)
+ __v_[__i] = __e_();
+ __y_ = __e_();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(false_type) { return __eval2(integral_constant<bool, __k & 1>()); }
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(true_type) { return __eval(__uratio<__k, _Rp>()); }
+
+ _LIBCPP_HIDE_FROM_ABI result_type __eval2(false_type) { return __eval(__uratio<__k / 2, 0x8000000000000000ull>()); }
+ _LIBCPP_HIDE_FROM_ABI result_type __eval2(true_type) { return __evalf<__k, 0>(); }
+
+ template <uint64_t _Np,
+ uint64_t _Dp,
+ __enable_if_t<(__uratio<_Np, _Dp>::num > 0xFFFFFFFFFFFFFFFFull / (_Max - _Min)), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(__uratio<_Np, _Dp>) {
+ return __evalf<__uratio<_Np, _Dp>::num, __uratio<_Np, _Dp>::den>();
+ }
+
+ template <uint64_t _Np,
+ uint64_t _Dp,
+ __enable_if_t<__uratio<_Np, _Dp>::num <= 0xFFFFFFFFFFFFFFFFull / (_Max - _Min), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(__uratio<_Np, _Dp>) {
+ const size_t __j = static_cast<size_t>(__uratio<_Np, _Dp>::num * (__y_ - _Min) / __uratio<_Np, _Dp>::den);
+ __y_ = __v_[__j];
+ __v_[__j] = __e_();
+ return __y_;
+ }
+
+ template <uint64_t __n, uint64_t __d>
+ _LIBCPP_HIDE_FROM_ABI result_type __evalf() {
+ const double __fp = __d == 0 ? __n / (2. * 0x8000000000000000ull) : __n / (double)__d;
+ const size_t __j = static_cast<size_t>(__fp * (__y_ - _Min));
+ __y_ = __v_[__j];
+ __v_[__j] = __e_();
+ return __y_;
+ }
+};
+
+template <class _Engine, size_t __k>
+_LIBCPP_CONSTEXPR const size_t shuffle_order_engine<_Engine, __k>::table_size;
+
+template <class _Eng, size_t _Kp>
+_LIBCPP_HIDE_FROM_ABI bool
+operator==(const shuffle_order_engine<_Eng, _Kp>& __x, const shuffle_order_engine<_Eng, _Kp>& __y) {
+ return __x.__y_ == __y.__y_ && std::equal(__x.__v_, __x.__v_ + _Kp, __y.__v_) && __x.__e_ == __y.__e_;
+}
+
+template <class _Eng, size_t _Kp>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const shuffle_order_engine<_Eng, _Kp>& __x, const shuffle_order_engine<_Eng, _Kp>& __y) {
+ return !(__x == __y);
+}
+
+template <class _CharT, class _Traits, class _Eng, size_t _Kp>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const shuffle_order_engine<_Eng, _Kp>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _Ostream;
+ __os.flags(_Ostream::dec | _Ostream::left);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.__e_ << __sp << __x.__v_[0];
+ for (size_t __i = 1; __i < _Kp; ++__i)
+ __os << __sp << __x.__v_[__i];
+ return __os << __sp << __x.__y_;
+}
+
+template <class _CharT, class _Traits, class _Eng, size_t _Kp>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, shuffle_order_engine<_Eng, _Kp>& __x) {
+ typedef typename shuffle_order_engine<_Eng, _Kp>::result_type result_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ _Eng __e;
+ result_type __vp[_Kp + 1];
+ __is >> __e;
+ for (size_t __i = 0; __i < _Kp + 1; ++__i)
+ __is >> __vp[__i];
+ if (!__is.fail()) {
+ __x.__e_ = __e;
+ for (size_t __i = 0; __i < _Kp; ++__i)
+ __x.__v_[__i] = __vp[__i];
+ __x.__y_ = __vp[_Kp];
+ }
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_SHUFFLE_ORDER_ENGINE_H
diff --git a/libcxx/include/__cxx03/__random/student_t_distribution.h b/libcxx/include/__cxx03/__random/student_t_distribution.h
new file mode 100644
index 00000000000000..110a856ee65868
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/student_t_distribution.h
@@ -0,0 +1,132 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_STUDENT_T_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_STUDENT_T_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/gamma_distribution.h>
+#include <__random/is_valid.h>
+#include <__random/normal_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS student_t_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __n_;
+
+ public:
+ typedef student_t_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __n = 1) : __n_(__n) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type n() const { return __n_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__n_ == __y.__n_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+ normal_distribution<result_type> __nd_;
+
+public:
+ // constructor and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI student_t_distribution() : student_t_distribution(1) {}
+ _LIBCPP_HIDE_FROM_ABI explicit student_t_distribution(result_type __n) : __p_(param_type(__n)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit student_t_distribution(result_type __n = 1) : __p_(param_type(__n)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit student_t_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() { __nd_.reset(); }
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type n() const { return __p_.n(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return -numeric_limits<result_type>::infinity(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const student_t_distribution& __x, const student_t_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const student_t_distribution& __x, const student_t_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _RealType>
+template <class _URNG>
+_RealType student_t_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ gamma_distribution<result_type> __gd(__p.n() * .5, 2);
+ return __nd_(__g) * std::sqrt(__p.n() / __gd(__g));
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const student_t_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ __os << __x.n();
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, student_t_distribution<_RT>& __x) {
+ typedef student_t_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __n;
+ __is >> __n;
+ if (!__is.fail())
+ __x.param(param_type(__n));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_STUDENT_T_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/subtract_with_carry_engine.h b/libcxx/include/__cxx03/__random/subtract_with_carry_engine.h
new file mode 100644
index 00000000000000..ec25fed49f9498
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/subtract_with_carry_engine.h
@@ -0,0 +1,276 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_SUBTRACT_WITH_CARRY_ENGINE_H
+#define _LIBCPP___RANDOM_SUBTRACT_WITH_CARRY_ENGINE_H
+
+#include <__algorithm/equal.h>
+#include <__algorithm/min.h>
+#include <__config>
+#include <__random/is_seed_sequence.h>
+#include <__random/linear_congruential_engine.h>
+#include <cstddef>
+#include <cstdint>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+class _LIBCPP_TEMPLATE_VIS subtract_with_carry_engine;
+
+template <class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x,
+ const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y);
+
+template <class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI bool operator!=(const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x,
+ const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y);
+
+template <class _CharT, class _Traits, class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x);
+
+template <class _CharT, class _Traits, class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x);
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+class _LIBCPP_TEMPLATE_VIS subtract_with_carry_engine {
+public:
+ // types
+ typedef _UIntType result_type;
+
+private:
+ result_type __x_[__r];
+ result_type __c_;
+ size_t __i_;
+
+ static _LIBCPP_CONSTEXPR const result_type _Dt = numeric_limits<result_type>::digits;
+ static_assert(0 < __w, "subtract_with_carry_engine invalid parameters");
+ static_assert(__w <= _Dt, "subtract_with_carry_engine invalid parameters");
+ static_assert(0 < __s, "subtract_with_carry_engine invalid parameters");
+ static_assert(__s < __r, "subtract_with_carry_engine invalid parameters");
+
+public:
+ static _LIBCPP_CONSTEXPR const result_type _Min = 0;
+ static _LIBCPP_CONSTEXPR const result_type _Max =
+ __w == _Dt ? result_type(~0) : (result_type(1) << __w) - result_type(1);
+ static_assert(_Min < _Max, "subtract_with_carry_engine invalid parameters");
+
+ // engine characteristics
+ static _LIBCPP_CONSTEXPR const size_t word_size = __w;
+ static _LIBCPP_CONSTEXPR const size_t short_lag = __s;
+ static _LIBCPP_CONSTEXPR const size_t long_lag = __r;
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+ static _LIBCPP_CONSTEXPR const result_type default_seed = 19780503u;
+
+ // constructors and seeding functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI subtract_with_carry_engine() : subtract_with_carry_engine(default_seed) {}
+ _LIBCPP_HIDE_FROM_ABI explicit subtract_with_carry_engine(result_type __sd) { seed(__sd); }
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit subtract_with_carry_engine(result_type __sd = default_seed) { seed(__sd); }
+#endif
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, subtract_with_carry_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit subtract_with_carry_engine(_Sseq& __q) {
+ seed(__q);
+ }
+ _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd = default_seed) {
+ seed(__sd, integral_constant<unsigned, 1 + (__w - 1) / 32>());
+ }
+ template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, subtract_with_carry_engine>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
+ __seed(__q, integral_constant<unsigned, 1 + (__w - 1) / 32>());
+ }
+
+ // generating functions
+ _LIBCPP_HIDE_FROM_ABI result_type operator()();
+ _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
+ for (; __z; --__z)
+ operator()();
+ }
+
+ template <class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+ friend bool operator==(const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x,
+ const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y);
+
+ template <class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+ friend bool operator!=(const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x,
+ const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y);
+
+ template <class _CharT, class _Traits, class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+ friend basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x);
+
+ template <class _CharT, class _Traits, class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+ friend basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x);
+
+private:
+ _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd, integral_constant<unsigned, 1>);
+ _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd, integral_constant<unsigned, 2>);
+ template <class _Sseq>
+ _LIBCPP_HIDE_FROM_ABI void __seed(_Sseq& __q, integral_constant<unsigned, 1>);
+ template <class _Sseq>
+ _LIBCPP_HIDE_FROM_ABI void __seed(_Sseq& __q, integral_constant<unsigned, 2>);
+};
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+_LIBCPP_CONSTEXPR const size_t subtract_with_carry_engine<_UIntType, __w, __s, __r>::word_size;
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+_LIBCPP_CONSTEXPR const size_t subtract_with_carry_engine<_UIntType, __w, __s, __r>::short_lag;
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+_LIBCPP_CONSTEXPR const size_t subtract_with_carry_engine<_UIntType, __w, __s, __r>::long_lag;
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+_LIBCPP_CONSTEXPR const typename subtract_with_carry_engine<_UIntType, __w, __s, __r>::result_type
+ subtract_with_carry_engine<_UIntType, __w, __s, __r>::default_seed;
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+void subtract_with_carry_engine<_UIntType, __w, __s, __r>::seed(result_type __sd, integral_constant<unsigned, 1>) {
+ linear_congruential_engine<result_type, 40014u, 0u, 2147483563u> __e(__sd == 0u ? default_seed : __sd);
+ for (size_t __i = 0; __i < __r; ++__i)
+ __x_[__i] = static_cast<result_type>(__e() & _Max);
+ __c_ = __x_[__r - 1] == 0;
+ __i_ = 0;
+}
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+void subtract_with_carry_engine<_UIntType, __w, __s, __r>::seed(result_type __sd, integral_constant<unsigned, 2>) {
+ linear_congruential_engine<result_type, 40014u, 0u, 2147483563u> __e(__sd == 0u ? default_seed : __sd);
+ for (size_t __i = 0; __i < __r; ++__i) {
+ result_type __e0 = __e();
+ __x_[__i] = static_cast<result_type>((__e0 + ((uint64_t)__e() << 32)) & _Max);
+ }
+ __c_ = __x_[__r - 1] == 0;
+ __i_ = 0;
+}
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+template <class _Sseq>
+void subtract_with_carry_engine<_UIntType, __w, __s, __r>::__seed(_Sseq& __q, integral_constant<unsigned, 1>) {
+ const unsigned __k = 1;
+ uint32_t __ar[__r * __k];
+ __q.generate(__ar, __ar + __r * __k);
+ for (size_t __i = 0; __i < __r; ++__i)
+ __x_[__i] = static_cast<result_type>(__ar[__i] & _Max);
+ __c_ = __x_[__r - 1] == 0;
+ __i_ = 0;
+}
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+template <class _Sseq>
+void subtract_with_carry_engine<_UIntType, __w, __s, __r>::__seed(_Sseq& __q, integral_constant<unsigned, 2>) {
+ const unsigned __k = 2;
+ uint32_t __ar[__r * __k];
+ __q.generate(__ar, __ar + __r * __k);
+ for (size_t __i = 0; __i < __r; ++__i)
+ __x_[__i] = static_cast<result_type>((__ar[2 * __i] + ((uint64_t)__ar[2 * __i + 1] << 32)) & _Max);
+ __c_ = __x_[__r - 1] == 0;
+ __i_ = 0;
+}
+
+template <class _UIntType, size_t __w, size_t __s, size_t __r>
+_UIntType subtract_with_carry_engine<_UIntType, __w, __s, __r>::operator()() {
+ const result_type& __xs = __x_[(__i_ + (__r - __s)) % __r];
+ result_type& __xr = __x_[__i_];
+ result_type __new_c = __c_ == 0 ? __xs < __xr : __xs != 0 ? __xs <= __xr : 1;
+ __xr = (__xs - __xr - __c_) & _Max;
+ __c_ = __new_c;
+ __i_ = (__i_ + 1) % __r;
+ return __xr;
+}
+
+template <class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x,
+ const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y) {
+ if (__x.__c_ != __y.__c_)
+ return false;
+ if (__x.__i_ == __y.__i_)
+ return std::equal(__x.__x_, __x.__x_ + _Rp, __y.__x_);
+ if (__x.__i_ == 0 || __y.__i_ == 0) {
+ size_t __j = std::min(_Rp - __x.__i_, _Rp - __y.__i_);
+ if (!std::equal(__x.__x_ + __x.__i_, __x.__x_ + __x.__i_ + __j, __y.__x_ + __y.__i_))
+ return false;
+ if (__x.__i_ == 0)
+ return std::equal(__x.__x_ + __j, __x.__x_ + _Rp, __y.__x_);
+ return std::equal(__x.__x_, __x.__x_ + (_Rp - __j), __y.__x_ + __j);
+ }
+ if (__x.__i_ < __y.__i_) {
+ size_t __j = _Rp - __y.__i_;
+ if (!std::equal(__x.__x_ + __x.__i_, __x.__x_ + (__x.__i_ + __j), __y.__x_ + __y.__i_))
+ return false;
+ if (!std::equal(__x.__x_ + (__x.__i_ + __j), __x.__x_ + _Rp, __y.__x_))
+ return false;
+ return std::equal(__x.__x_, __x.__x_ + __x.__i_, __y.__x_ + (_Rp - (__x.__i_ + __j)));
+ }
+ size_t __j = _Rp - __x.__i_;
+ if (!std::equal(__y.__x_ + __y.__i_, __y.__x_ + (__y.__i_ + __j), __x.__x_ + __x.__i_))
+ return false;
+ if (!std::equal(__y.__x_ + (__y.__i_ + __j), __y.__x_ + _Rp, __x.__x_))
+ return false;
+ return std::equal(__y.__x_, __y.__x_ + __y.__i_, __x.__x_ + (_Rp - (__y.__i_ + __j)));
+}
+
+template <class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x,
+ const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y) {
+ return !(__x == __y);
+}
+
+template <class _CharT, class _Traits, class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _Ostream;
+ __os.flags(_Ostream::dec | _Ostream::left);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.__x_[__x.__i_];
+ for (size_t __j = __x.__i_ + 1; __j < _Rp; ++__j)
+ __os << __sp << __x.__x_[__j];
+ for (size_t __j = 0; __j < __x.__i_; ++__j)
+ __os << __sp << __x.__x_[__j];
+ __os << __sp << __x.__c_;
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _UInt, size_t _Wp, size_t _Sp, size_t _Rp>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ _UInt __t[_Rp + 1];
+ for (size_t __i = 0; __i < _Rp + 1; ++__i)
+ __is >> __t[__i];
+ if (!__is.fail()) {
+ for (size_t __i = 0; __i < _Rp; ++__i)
+ __x.__x_[__i] = __t[__i];
+ __x.__c_ = __t[_Rp];
+ __x.__i_ = 0;
+ }
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_SUBTRACT_WITH_CARRY_ENGINE_H
diff --git a/libcxx/include/__cxx03/__random/uniform_int_distribution.h b/libcxx/include/__cxx03/__random/uniform_int_distribution.h
new file mode 100644
index 00000000000000..4e3ca3efe56866
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/uniform_int_distribution.h
@@ -0,0 +1,264 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_UNIFORM_INT_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_UNIFORM_INT_DISTRIBUTION_H
+
+#include <__bit/countl.h>
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/log2.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/make_unsigned.h>
+#include <cstddef>
+#include <cstdint>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Engine, class _UIntType>
+class __independent_bits_engine {
+public:
+ // types
+ typedef _UIntType result_type;
+
+private:
+ typedef typename _Engine::result_type _Engine_result_type;
+ typedef __conditional_t<sizeof(_Engine_result_type) <= sizeof(result_type), result_type, _Engine_result_type>
+ _Working_result_type;
+
+ _Engine& __e_;
+ size_t __w_;
+ size_t __w0_;
+ size_t __n_;
+ size_t __n0_;
+ _Working_result_type __y0_;
+ _Working_result_type __y1_;
+ _Engine_result_type __mask0_;
+ _Engine_result_type __mask1_;
+
+#ifdef _LIBCPP_CXX03_LANG
+ static const _Working_result_type _Rp = _Engine::_Max - _Engine::_Min + _Working_result_type(1);
+#else
+ static _LIBCPP_CONSTEXPR const _Working_result_type _Rp = _Engine::max() - _Engine::min() + _Working_result_type(1);
+#endif
+ static _LIBCPP_CONSTEXPR const size_t __m = __log2<_Working_result_type, _Rp>::value;
+ static _LIBCPP_CONSTEXPR const size_t _WDt = numeric_limits<_Working_result_type>::digits;
+ static _LIBCPP_CONSTEXPR const size_t _EDt = numeric_limits<_Engine_result_type>::digits;
+
+public:
+ // constructors and seeding functions
+ _LIBCPP_HIDE_FROM_ABI __independent_bits_engine(_Engine& __e, size_t __w);
+
+ // generating functions
+ _LIBCPP_HIDE_FROM_ABI result_type operator()() { return __eval(integral_constant<bool, _Rp != 0>()); }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(false_type);
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(true_type);
+};
+
+template <class _Engine, class _UIntType>
+__independent_bits_engine<_Engine, _UIntType>::__independent_bits_engine(_Engine& __e, size_t __w)
+ : __e_(__e), __w_(__w) {
+ __n_ = __w_ / __m + (__w_ % __m != 0);
+ __w0_ = __w_ / __n_;
+ if (_Rp == 0)
+ __y0_ = _Rp;
+ else if (__w0_ < _WDt)
+ __y0_ = (_Rp >> __w0_) << __w0_;
+ else
+ __y0_ = 0;
+ if (_Rp - __y0_ > __y0_ / __n_) {
+ ++__n_;
+ __w0_ = __w_ / __n_;
+ if (__w0_ < _WDt)
+ __y0_ = (_Rp >> __w0_) << __w0_;
+ else
+ __y0_ = 0;
+ }
+ __n0_ = __n_ - __w_ % __n_;
+ if (__w0_ < _WDt - 1)
+ __y1_ = (_Rp >> (__w0_ + 1)) << (__w0_ + 1);
+ else
+ __y1_ = 0;
+ __mask0_ = __w0_ > 0 ? _Engine_result_type(~0) >> (_EDt - __w0_) : _Engine_result_type(0);
+ __mask1_ = __w0_ < _EDt - 1 ? _Engine_result_type(~0) >> (_EDt - (__w0_ + 1)) : _Engine_result_type(~0);
+}
+
+template <class _Engine, class _UIntType>
+inline _UIntType __independent_bits_engine<_Engine, _UIntType>::__eval(false_type) {
+ return static_cast<result_type>(__e_() & __mask0_);
+}
+
+template <class _Engine, class _UIntType>
+_UIntType __independent_bits_engine<_Engine, _UIntType>::__eval(true_type) {
+ const size_t __w_rt = numeric_limits<result_type>::digits;
+ result_type __sp = 0;
+ for (size_t __k = 0; __k < __n0_; ++__k) {
+ _Engine_result_type __u;
+ do {
+ __u = __e_() - _Engine::min();
+ } while (__u >= __y0_);
+ if (__w0_ < __w_rt)
+ __sp <<= __w0_;
+ else
+ __sp = 0;
+ __sp += __u & __mask0_;
+ }
+ for (size_t __k = __n0_; __k < __n_; ++__k) {
+ _Engine_result_type __u;
+ do {
+ __u = __e_() - _Engine::min();
+ } while (__u >= __y1_);
+ if (__w0_ < __w_rt - 1)
+ __sp <<= __w0_ + 1;
+ else
+ __sp = 0;
+ __sp += __u & __mask1_;
+ }
+ return __sp;
+}
+
+template <class _IntType = int>
+class uniform_int_distribution {
+ static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");
+
+public:
+ // types
+ typedef _IntType result_type;
+
+ class param_type {
+ result_type __a_;
+ result_type __b_;
+
+ public:
+ typedef uniform_int_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __a = 0, result_type __b = numeric_limits<result_type>::max())
+ : __a_(__a), __b_(__b) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __a_; }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __b_; }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;
+ }
+ _LIBCPP_HIDE_FROM_ABI friend bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI uniform_int_distribution() : uniform_int_distribution(0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit uniform_int_distribution(
+ result_type __a, result_type __b = numeric_limits<result_type>::max())
+ : __p_(param_type(__a, __b)) {}
+#else
+ explicit uniform_int_distribution(result_type __a = 0, result_type __b = numeric_limits<result_type>::max())
+ : __p_(param_type(__a, __b)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit uniform_int_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __p_.a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return b(); }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool
+ operator==(const uniform_int_distribution& __x, const uniform_int_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ _LIBCPP_HIDE_FROM_ABI friend bool
+ operator!=(const uniform_int_distribution& __x, const uniform_int_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _IntType>
+template <class _URNG>
+typename uniform_int_distribution<_IntType>::result_type uniform_int_distribution<_IntType>::operator()(
+ _URNG& __g, const param_type& __p) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ typedef __conditional_t<sizeof(result_type) <= sizeof(uint32_t), uint32_t, __make_unsigned_t<result_type> > _UIntType;
+ const _UIntType __rp = _UIntType(__p.b()) - _UIntType(__p.a()) + _UIntType(1);
+ if (__rp == 1)
+ return __p.a();
+ const size_t __dt = numeric_limits<_UIntType>::digits;
+ typedef __independent_bits_engine<_URNG, _UIntType> _Eng;
+ if (__rp == 0)
+ return static_cast<result_type>(_Eng(__g, __dt)());
+ size_t __w = __dt - std::__countl_zero(__rp) - 1;
+ if ((__rp & (numeric_limits<_UIntType>::max() >> (__dt - __w))) != 0)
+ ++__w;
+ _Eng __e(__g, __w);
+ _UIntType __u;
+ do {
+ __u = __e();
+ } while (__u >= __rp);
+ return static_cast<result_type>(__u + __p.a());
+}
+
+template <class _CharT, class _Traits, class _IT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const uniform_int_distribution<_IT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _Ostream;
+ __os.flags(_Ostream::dec | _Ostream::left);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ return __os << __x.a() << __sp << __x.b();
+}
+
+template <class _CharT, class _Traits, class _IT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, uniform_int_distribution<_IT>& __x) {
+ typedef uniform_int_distribution<_IT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __a;
+ result_type __b;
+ __is >> __a >> __b;
+ if (!__is.fail())
+ __x.param(param_type(__a, __b));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_UNIFORM_INT_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/uniform_random_bit_generator.h b/libcxx/include/__cxx03/__random/uniform_random_bit_generator.h
new file mode 100644
index 00000000000000..4076f19b2cb2c1
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/uniform_random_bit_generator.h
@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_UNIFORM_RANDOM_BIT_GENERATOR_H
+#define _LIBCPP___RANDOM_UNIFORM_RANDOM_BIT_GENERATOR_H
+
+#include <__concepts/arithmetic.h>
+#include <__concepts/invocable.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/invoke.h>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [rand.req.urng]
+template <class _Gen>
+concept uniform_random_bit_generator = invocable<_Gen&> && unsigned_integral<invoke_result_t<_Gen&>> && requires {
+ { _Gen::min() } -> same_as<invoke_result_t<_Gen&>>;
+ { _Gen::max() } -> same_as<invoke_result_t<_Gen&>>;
+ requires bool_constant<(_Gen::min() < _Gen::max())>::value;
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_UNIFORM_RANDOM_BIT_GENERATOR_H
diff --git a/libcxx/include/__cxx03/__random/uniform_real_distribution.h b/libcxx/include/__cxx03/__random/uniform_real_distribution.h
new file mode 100644
index 00000000000000..250cb8bab58cf6
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/uniform_real_distribution.h
@@ -0,0 +1,138 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_UNIFORM_REAL_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_UNIFORM_REAL_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/generate_canonical.h>
+#include <__random/is_valid.h>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS uniform_real_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __a_;
+ result_type __b_;
+
+ public:
+ typedef uniform_real_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __a = 0, result_type __b = 1) : __a_(__a), __b_(__b) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __a_; }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __b_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI uniform_real_distribution() : uniform_real_distribution(0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit uniform_real_distribution(result_type __a, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit uniform_real_distribution(result_type __a = 0, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit uniform_real_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __p_.a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return b(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const uniform_real_distribution& __x, const uniform_real_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const uniform_real_distribution& __x, const uniform_real_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _RealType>
+template <class _URNG>
+inline typename uniform_real_distribution<_RealType>::result_type
+uniform_real_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ return (__p.b() - __p.a()) * std::generate_canonical<_RealType, numeric_limits<_RealType>::digits>(__g) + __p.a();
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const uniform_real_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ return __os << __x.a() << __sp << __x.b();
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, uniform_real_distribution<_RT>& __x) {
+ typedef uniform_real_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __a;
+ result_type __b;
+ __is >> __a >> __b;
+ if (!__is.fail())
+ __x.param(param_type(__a, __b));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_UNIFORM_REAL_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__random/weibull_distribution.h b/libcxx/include/__cxx03/__random/weibull_distribution.h
new file mode 100644
index 00000000000000..aa3d63c8e8663d
--- /dev/null
+++ b/libcxx/include/__cxx03/__random/weibull_distribution.h
@@ -0,0 +1,132 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_WEIBULL_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_WEIBULL_DISTRIBUTION_H
+
+#include <__config>
+#include <__random/exponential_distribution.h>
+#include <__random/is_valid.h>
+#include <cmath>
+#include <iosfwd>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _RealType = double>
+class _LIBCPP_TEMPLATE_VIS weibull_distribution {
+ static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+ "RealType must be a supported floating-point type");
+
+public:
+ // types
+ typedef _RealType result_type;
+
+ class _LIBCPP_TEMPLATE_VIS param_type {
+ result_type __a_;
+ result_type __b_;
+
+ public:
+ typedef weibull_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __a = 1, result_type __b = 1) : __a_(__a), __b_(__b) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __a_; }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __b_; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI weibull_distribution() : weibull_distribution(1) {}
+ _LIBCPP_HIDE_FROM_ABI explicit weibull_distribution(result_type __a, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+#else
+ _LIBCPP_HIDE_FROM_ABI explicit weibull_distribution(result_type __a = 1, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit weibull_distribution(const param_type& __p) : __p_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+ // generating functions
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+ return (*this)(__g, __p_);
+ }
+ template <class _URNG>
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {
+ return __p.b() * std::pow(exponential_distribution<result_type>()(__g), 1 / __p.a());
+ }
+
+ // property functions
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __p_.a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }
+
+ _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+ _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+ _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const weibull_distribution& __x, const weibull_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const weibull_distribution& __x, const weibull_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const weibull_distribution<_RT>& __x) {
+ __save_flags<_CharT, _Traits> __lx(__os);
+ typedef basic_ostream<_CharT, _Traits> _OStream;
+ __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.a() << __sp << __x.b();
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, weibull_distribution<_RT>& __x) {
+ typedef weibull_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __a;
+ result_type __b;
+ __is >> __a >> __b;
+ if (!__is.fail())
+ __x.param(param_type(__a, __b));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_WEIBULL_DISTRIBUTION_H
diff --git a/libcxx/include/__cxx03/__ranges/access.h b/libcxx/include/__cxx03/__ranges/access.h
new file mode 100644
index 00000000000000..c0a40c5e10178a
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/access.h
@@ -0,0 +1,210 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_ACCESS_H
+#define _LIBCPP___RANGES_ACCESS_H
+
+#include <__concepts/class_or_enum.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/readable_traits.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/auto_cast.h>
+#include <__utility/declval.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <class _Tp>
+concept __can_borrow = is_lvalue_reference_v<_Tp> || enable_borrowed_range<remove_cvref_t<_Tp>>;
+} // namespace ranges
+
+// [range.access.begin]
+
+namespace ranges {
+namespace __begin {
+template <class _Tp>
+concept __member_begin = __can_borrow<_Tp> && requires(_Tp&& __t) {
+ { _LIBCPP_AUTO_CAST(__t.begin()) } -> input_or_output_iterator;
+};
+
+void begin() = delete;
+
+template <class _Tp>
+concept __unqualified_begin =
+ !__member_begin<_Tp> && __can_borrow<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) {
+ { _LIBCPP_AUTO_CAST(begin(__t)) } -> input_or_output_iterator;
+ };
+
+struct __fn {
+ template <class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp (&__t)[]) const noexcept
+ requires(sizeof(_Tp) >= 0) // Disallow incomplete element types.
+ {
+ return __t + 0;
+ }
+
+ template <class _Tp, size_t _Np>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp (&__t)[_Np]) const noexcept
+ requires(sizeof(_Tp) >= 0) // Disallow incomplete element types.
+ {
+ return __t + 0;
+ }
+
+ template <class _Tp>
+ requires __member_begin<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(__t.begin()))) {
+ return _LIBCPP_AUTO_CAST(__t.begin());
+ }
+
+ template <class _Tp>
+ requires __unqualified_begin<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(begin(__t)))) {
+ return _LIBCPP_AUTO_CAST(begin(__t));
+ }
+
+ void operator()(auto&&) const = delete;
+};
+} // namespace __begin
+
+inline namespace __cpo {
+inline constexpr auto begin = __begin::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+// [range.range]
+
+namespace ranges {
+template <class _Tp>
+using iterator_t = decltype(ranges::begin(std::declval<_Tp&>()));
+} // namespace ranges
+
+// [range.access.end]
+
+namespace ranges {
+namespace __end {
+template <class _Tp>
+concept __member_end = __can_borrow<_Tp> && requires(_Tp&& __t) {
+ typename iterator_t<_Tp>;
+ { _LIBCPP_AUTO_CAST(__t.end()) } -> sentinel_for<iterator_t<_Tp>>;
+};
+
+void end() = delete;
+
+template <class _Tp>
+concept __unqualified_end =
+ !__member_end<_Tp> && __can_borrow<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) {
+ typename iterator_t<_Tp>;
+ { _LIBCPP_AUTO_CAST(end(__t)) } -> sentinel_for<iterator_t<_Tp>>;
+ };
+
+struct __fn {
+ template <class _Tp, size_t _Np>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp (&__t)[_Np]) const noexcept
+ requires(sizeof(_Tp) >= 0) // Disallow incomplete element types.
+ {
+ return __t + _Np;
+ }
+
+ template <class _Tp>
+ requires __member_end<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(__t.end()))) {
+ return _LIBCPP_AUTO_CAST(__t.end());
+ }
+
+ template <class _Tp>
+ requires __unqualified_end<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(end(__t)))) {
+ return _LIBCPP_AUTO_CAST(end(__t));
+ }
+
+ void operator()(auto&&) const = delete;
+};
+} // namespace __end
+
+inline namespace __cpo {
+inline constexpr auto end = __end::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+// [range.access.cbegin]
+
+namespace ranges {
+namespace __cbegin {
+struct __fn {
+ template <class _Tp>
+ requires is_lvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::begin(static_cast<const remove_reference_t<_Tp>&>(__t))))
+ -> decltype(ranges::begin(static_cast<const remove_reference_t<_Tp>&>(__t))) {
+ return ranges::begin(static_cast<const remove_reference_t<_Tp>&>(__t));
+ }
+
+ template <class _Tp>
+ requires is_rvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::begin(static_cast<const _Tp&&>(__t))))
+ -> decltype(ranges::begin(static_cast<const _Tp&&>(__t))) {
+ return ranges::begin(static_cast<const _Tp&&>(__t));
+ }
+};
+} // namespace __cbegin
+
+inline namespace __cpo {
+inline constexpr auto cbegin = __cbegin::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+// [range.access.cend]
+
+namespace ranges {
+namespace __cend {
+struct __fn {
+ template <class _Tp>
+ requires is_lvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::end(static_cast<const remove_reference_t<_Tp>&>(__t))))
+ -> decltype(ranges::end(static_cast<const remove_reference_t<_Tp>&>(__t))) {
+ return ranges::end(static_cast<const remove_reference_t<_Tp>&>(__t));
+ }
+
+ template <class _Tp>
+ requires is_rvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept(
+ noexcept(ranges::end(static_cast<const _Tp&&>(__t)))) -> decltype(ranges::end(static_cast<const _Tp&&>(__t))) {
+ return ranges::end(static_cast<const _Tp&&>(__t));
+ }
+};
+} // namespace __cend
+
+inline namespace __cpo {
+inline constexpr auto cend = __cend::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_ACCESS_H
diff --git a/libcxx/include/__cxx03/__ranges/all.h b/libcxx/include/__cxx03/__ranges/all.h
new file mode 100644
index 00000000000000..023cee6caa9a2a
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/all.h
@@ -0,0 +1,78 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_ALL_H
+#define _LIBCPP___RANGES_ALL_H
+
+#include <__config>
+#include <__functional/compose.h> // TODO(modules): Those should not be required
+#include <__functional/perfect_forward.h> //
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/owning_view.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/ref_view.h>
+#include <__type_traits/decay.h>
+#include <__utility/auto_cast.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges::views {
+
+namespace __all {
+struct __fn : __range_adaptor_closure<__fn> {
+ template <class _Tp>
+ requires ranges::view<decay_t<_Tp>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept(
+ noexcept(_LIBCPP_AUTO_CAST(std::forward<_Tp>(__t)))) -> decltype(_LIBCPP_AUTO_CAST(std::forward<_Tp>(__t))) {
+ return _LIBCPP_AUTO_CAST(std::forward<_Tp>(__t));
+ }
+
+ template <class _Tp>
+ requires(!ranges::view<decay_t<_Tp>>) && requires(_Tp&& __t) { ranges::ref_view{std::forward<_Tp>(__t)}; }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::ref_view{std::forward<_Tp>(__t)})) {
+ return ranges::ref_view{std::forward<_Tp>(__t)};
+ }
+
+ template <class _Tp>
+ requires(
+ !ranges::view<decay_t<_Tp>> && !requires(_Tp&& __t) { ranges::ref_view{std::forward<_Tp>(__t)}; } &&
+ requires(_Tp&& __t) { ranges::owning_view{std::forward<_Tp>(__t)}; })
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::owning_view{std::forward<_Tp>(__t)})) {
+ return ranges::owning_view{std::forward<_Tp>(__t)};
+ }
+};
+} // namespace __all
+
+inline namespace __cpo {
+inline constexpr auto all = __all::__fn{};
+} // namespace __cpo
+
+template <ranges::viewable_range _Range>
+using all_t = decltype(views::all(std::declval<_Range>()));
+
+} // namespace ranges::views
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_ALL_H
diff --git a/libcxx/include/__cxx03/__ranges/as_rvalue_view.h b/libcxx/include/__cxx03/__ranges/as_rvalue_view.h
new file mode 100644
index 00000000000000..5849a6c3683960
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/as_rvalue_view.h
@@ -0,0 +1,142 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_AS_RVALUE_H
+#define _LIBCPP___RANGES_AS_RVALUE_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/move_iterator.h>
+#include <__iterator/move_sentinel.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/size.h>
+#include <__ranges/view_interface.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+template <view _View>
+ requires input_range<_View>
+class as_rvalue_view : public view_interface<as_rvalue_view<_View>> {
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI as_rvalue_view()
+ requires default_initializable<_View>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit as_rvalue_view(_View __base) : __base_(std::move(__base)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
+ requires(!__simple_view<_View>)
+ {
+ return move_iterator(ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires range<const _View>
+ {
+ return move_iterator(ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end()
+ requires(!__simple_view<_View>)
+ {
+ if constexpr (common_range<_View>) {
+ return move_iterator(ranges::end(__base_));
+ } else {
+ return move_sentinel(ranges::end(__base_));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires range<const _View>
+ {
+ if constexpr (common_range<const _View>) {
+ return move_iterator(ranges::end(__base_));
+ } else {
+ return move_sentinel(ranges::end(__base_));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires sized_range<_View>
+ {
+ return ranges::size(__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<const _View>
+ {
+ return ranges::size(__base_);
+ }
+};
+
+template <class _Range>
+as_rvalue_view(_Range&&) -> as_rvalue_view<views::all_t<_Range>>;
+
+template <class _View>
+inline constexpr bool enable_borrowed_range<as_rvalue_view<_View>> = enable_borrowed_range<_View>;
+
+namespace views {
+namespace __as_rvalue {
+struct __fn : __range_adaptor_closure<__fn> {
+ template <class _Range>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto
+ operator()(_Range&& __range) noexcept(noexcept(as_rvalue_view(std::forward<_Range>(__range))))
+ -> decltype(/*--------------------------*/ as_rvalue_view(std::forward<_Range>(__range))) {
+ return /*---------------------------------*/ as_rvalue_view(std::forward<_Range>(__range));
+ }
+
+ template <class _Range>
+ requires same_as<range_rvalue_reference_t<_Range>, range_reference_t<_Range>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto
+ operator()(_Range&& __range) noexcept(noexcept(views::all(std::forward<_Range>(__range))))
+ -> decltype(/*--------------------------*/ views::all(std::forward<_Range>(__range))) {
+ return /*---------------------------------*/ views::all(std::forward<_Range>(__range));
+ }
+};
+} // namespace __as_rvalue
+
+inline namespace __cpo {
+inline constexpr auto as_rvalue = __as_rvalue::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_AS_RVALUE_H
diff --git a/libcxx/include/__cxx03/__ranges/chunk_by_view.h b/libcxx/include/__cxx03/__ranges/chunk_by_view.h
new file mode 100644
index 00000000000000..00014d9f10ae88
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/chunk_by_view.h
@@ -0,0 +1,235 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_CHUNK_BY_VIEW_H
+#define _LIBCPP___RANGES_CHUNK_BY_VIEW_H
+
+#include <__algorithm/ranges_adjacent_find.h>
+#include <__assert>
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/prev.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/movable_box.h>
+#include <__ranges/non_propagating_cache.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/reverse_view.h>
+#include <__ranges/subrange.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_object.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+namespace ranges {
+
+template <forward_range _View, indirect_binary_predicate<iterator_t<_View>, iterator_t<_View>> _Pred>
+ requires view<_View> && is_object_v<_Pred>
+class _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS chunk_by_view : public view_interface<chunk_by_view<_View, _Pred>> {
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+ _LIBCPP_NO_UNIQUE_ADDRESS __movable_box<_Pred> __pred_;
+
+ // We cache the result of begin() to allow providing an amortized O(1).
+ using _Cache = __non_propagating_cache<iterator_t<_View>>;
+ _Cache __cached_begin_;
+
+ class __iterator;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_View> __find_next(iterator_t<_View> __current) {
+ // Note: this duplicates a check in `optional` but provides a better error message.
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __pred_.__has_value(), "Trying to call __find_next() on a chunk_by_view that does not have a valid predicate.");
+ auto __reversed_pred = [this]<class _Tp, class _Up>(_Tp&& __x, _Up&& __y) -> bool {
+ return !std::invoke(*__pred_, std::forward<_Tp>(__x), std::forward<_Up>(__y));
+ };
+ return ranges::next(
+ ranges::adjacent_find(__current, ranges::end(__base_), __reversed_pred), 1, ranges::end(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_View> __find_prev(iterator_t<_View> __current)
+ requires bidirectional_range<_View>
+ {
+ // Attempting to decrement a begin iterator is a no-op (`__find_prev` would return the same argument given to it).
+ _LIBCPP_ASSERT_PEDANTIC(__current != ranges::begin(__base_), "Trying to call __find_prev() on a begin iterator.");
+ // Note: this duplicates a check in `optional` but provides a better error message.
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __pred_.__has_value(), "Trying to call __find_prev() on a chunk_by_view that does not have a valid predicate.");
+
+ auto __first = ranges::begin(__base_);
+ reverse_view __reversed{subrange{__first, __current}};
+ auto __reversed_pred = [this]<class _Tp, class _Up>(_Tp&& __x, _Up&& __y) -> bool {
+ return !std::invoke(*__pred_, std::forward<_Up>(__y), std::forward<_Tp>(__x));
+ };
+ return ranges::prev(ranges::adjacent_find(__reversed, __reversed_pred).base(), 1, std::move(__first));
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI chunk_by_view()
+ requires default_initializable<_View> && default_initializable<_Pred>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit chunk_by_view(_View __base, _Pred __pred)
+ : __base_(std::move(__base)), __pred_(in_place, std::move(__pred)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Pred& pred() const { return *__pred_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator begin() {
+ // Note: this duplicates a check in `optional` but provides a better error message.
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __pred_.__has_value(), "Trying to call begin() on a chunk_by_view that does not have a valid predicate.");
+
+ auto __first = ranges::begin(__base_);
+ if (!__cached_begin_.__has_value()) {
+ __cached_begin_.__emplace(__find_next(__first));
+ }
+ return {*this, std::move(__first), *__cached_begin_};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() {
+ if constexpr (common_range<_View>) {
+ return __iterator{*this, ranges::end(__base_), ranges::end(__base_)};
+ } else {
+ return default_sentinel;
+ }
+ }
+};
+
+template <class _Range, class _Pred>
+chunk_by_view(_Range&&, _Pred) -> chunk_by_view<views::all_t<_Range>, _Pred>;
+
+template <forward_range _View, indirect_binary_predicate<iterator_t<_View>, iterator_t<_View>> _Pred>
+ requires view<_View> && is_object_v<_Pred>
+class chunk_by_view<_View, _Pred>::__iterator {
+ friend chunk_by_view;
+
+ chunk_by_view* __parent_ = nullptr;
+ _LIBCPP_NO_UNIQUE_ADDRESS iterator_t<_View> __current_ = iterator_t<_View>();
+ _LIBCPP_NO_UNIQUE_ADDRESS iterator_t<_View> __next_ = iterator_t<_View>();
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(
+ chunk_by_view& __parent, iterator_t<_View> __current, iterator_t<_View> __next)
+ : __parent_(std::addressof(__parent)), __current_(__current), __next_(__next) {}
+
+public:
+ using value_type = subrange<iterator_t<_View>>;
+ using difference_type = range_difference_t<_View>;
+ using iterator_category = input_iterator_tag;
+ using iterator_concept = conditional_t<bidirectional_range<_View>, bidirectional_iterator_tag, forward_iterator_tag>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type operator*() const {
+ // If the iterator is at end, this would return an empty range which can be checked by the calling code and doesn't
+ // necessarily lead to a bad access.
+ _LIBCPP_ASSERT_PEDANTIC(__current_ != __next_, "Trying to dereference past-the-end chunk_by_view iterator.");
+ return {__current_, __next_};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ // Attempting to increment an end iterator is a no-op (`__find_next` would return the same argument given to it).
+ _LIBCPP_ASSERT_PEDANTIC(__current_ != __next_, "Trying to increment past end chunk_by_view iterator.");
+ __current_ = __next_;
+ __next_ = __parent_->__find_next(__current_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int) {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--()
+ requires bidirectional_range<_View>
+ {
+ __next_ = __current_;
+ __current_ = __parent_->__find_prev(__next_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int)
+ requires bidirectional_range<_View>
+ {
+ auto __tmp = *this;
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y) {
+ return __x.__current_ == __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, default_sentinel_t) {
+ return __x.__current_ == __x.__next_;
+ }
+};
+
+namespace views {
+namespace __chunk_by {
+struct __fn {
+ template <class _Range, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Pred&& __pred) const
+ noexcept(noexcept(/**/ chunk_by_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))))
+ -> decltype(/*--*/ chunk_by_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))) {
+ return /*-------------*/ chunk_by_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred));
+ }
+
+ template <class _Pred>
+ requires constructible_from<decay_t<_Pred>, _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Pred&& __pred) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Pred>, _Pred>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Pred>(__pred)));
+ }
+};
+} // namespace __chunk_by
+
+inline namespace __cpo {
+inline constexpr auto chunk_by = __chunk_by::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_CHUNK_BY_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/common_view.h b/libcxx/include/__cxx03/__ranges/common_view.h
new file mode 100644
index 00000000000000..133236dd1d78ab
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/common_view.h
@@ -0,0 +1,142 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_COMMON_VIEW_H
+#define _LIBCPP___RANGES_COMMON_VIEW_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/copyable.h>
+#include <__config>
+#include <__iterator/common_iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/size.h>
+#include <__ranges/view_interface.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <view _View>
+ requires(!common_range<_View> && copyable<iterator_t<_View>>)
+class common_view : public view_interface<common_view<_View>> {
+ _View __base_ = _View();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI common_view()
+ requires default_initializable<_View>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit common_view(_View __v) : __base_(std::move(__v)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() {
+ if constexpr (random_access_range<_View> && sized_range<_View>)
+ return ranges::begin(__base_);
+ else
+ return common_iterator<iterator_t<_View>, sentinel_t<_View>>(ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires range<const _View>
+ {
+ if constexpr (random_access_range<const _View> && sized_range<const _View>)
+ return ranges::begin(__base_);
+ else
+ return common_iterator<iterator_t<const _View>, sentinel_t<const _View>>(ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() {
+ if constexpr (random_access_range<_View> && sized_range<_View>)
+ return ranges::begin(__base_) + ranges::size(__base_);
+ else
+ return common_iterator<iterator_t<_View>, sentinel_t<_View>>(ranges::end(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires range<const _View>
+ {
+ if constexpr (random_access_range<const _View> && sized_range<const _View>)
+ return ranges::begin(__base_) + ranges::size(__base_);
+ else
+ return common_iterator<iterator_t<const _View>, sentinel_t<const _View>>(ranges::end(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires sized_range<_View>
+ {
+ return ranges::size(__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<const _View>
+ {
+ return ranges::size(__base_);
+ }
+};
+
+template <class _Range>
+common_view(_Range&&) -> common_view<views::all_t<_Range>>;
+
+template <class _View>
+inline constexpr bool enable_borrowed_range<common_view<_View>> = enable_borrowed_range<_View>;
+
+namespace views {
+namespace __common {
+struct __fn : __range_adaptor_closure<__fn> {
+ template <class _Range>
+ requires common_range<_Range>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const noexcept(
+ noexcept(views::all(std::forward<_Range>(__range)))) -> decltype(views::all(std::forward<_Range>(__range))) {
+ return views::all(std::forward<_Range>(__range));
+ }
+
+ template <class _Range>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const noexcept(noexcept(common_view{
+ std::forward<_Range>(__range)})) -> decltype(common_view{std::forward<_Range>(__range)}) {
+ return common_view{std::forward<_Range>(__range)};
+ }
+};
+} // namespace __common
+
+inline namespace __cpo {
+inline constexpr auto common = __common::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_COMMON_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/concepts.h b/libcxx/include/__cxx03/__ranges/concepts.h
new file mode 100644
index 00000000000000..674a3f359ff99c
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/concepts.h
@@ -0,0 +1,142 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_CONCEPTS_H
+#define _LIBCPP___RANGES_CONCEPTS_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/movable.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/readable_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/data.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/enable_view.h>
+#include <__ranges/size.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+// [range.range]
+
+template <class _Tp>
+concept range = requires(_Tp& __t) {
+ ranges::begin(__t); // sometimes equality-preserving
+ ranges::end(__t);
+};
+
+template <class _Tp>
+concept input_range = range<_Tp> && input_iterator<iterator_t<_Tp>>;
+
+template <class _Range>
+concept borrowed_range =
+ range<_Range> && (is_lvalue_reference_v<_Range> || enable_borrowed_range<remove_cvref_t<_Range>>);
+
+// `iterator_t` defined in <__ranges/access.h>
+
+template <range _Rp>
+using sentinel_t = decltype(ranges::end(std::declval<_Rp&>()));
+
+template <range _Rp>
+using range_difference_t = iter_difference_t<iterator_t<_Rp>>;
+
+template <range _Rp>
+using range_value_t = iter_value_t<iterator_t<_Rp>>;
+
+template <range _Rp>
+using range_reference_t = iter_reference_t<iterator_t<_Rp>>;
+
+template <range _Rp>
+using range_rvalue_reference_t = iter_rvalue_reference_t<iterator_t<_Rp>>;
+
+template <range _Rp>
+using range_common_reference_t = iter_common_reference_t<iterator_t<_Rp>>;
+
+// [range.sized]
+template <class _Tp>
+concept sized_range = range<_Tp> && requires(_Tp& __t) { ranges::size(__t); };
+
+template <sized_range _Rp>
+using range_size_t = decltype(ranges::size(std::declval<_Rp&>()));
+
+// `disable_sized_range` defined in `<__ranges/size.h>`
+
+// [range.view], views
+
+// `enable_view` defined in <__ranges/enable_view.h>
+// `view_base` defined in <__ranges/enable_view.h>
+
+template <class _Tp>
+concept view = range<_Tp> && movable<_Tp> && enable_view<_Tp>;
+
+template <class _Range>
+concept __simple_view =
+ view<_Range> && range<const _Range> && same_as<iterator_t<_Range>, iterator_t<const _Range>> &&
+ same_as<sentinel_t<_Range>, sentinel_t<const _Range>>;
+
+// [range.refinements], other range refinements
+template <class _Rp, class _Tp>
+concept output_range = range<_Rp> && output_iterator<iterator_t<_Rp>, _Tp>;
+
+template <class _Tp>
+concept forward_range = input_range<_Tp> && forward_iterator<iterator_t<_Tp>>;
+
+template <class _Tp>
+concept bidirectional_range = forward_range<_Tp> && bidirectional_iterator<iterator_t<_Tp>>;
+
+template <class _Tp>
+concept random_access_range = bidirectional_range<_Tp> && random_access_iterator<iterator_t<_Tp>>;
+
+template <class _Tp>
+concept contiguous_range = random_access_range<_Tp> && contiguous_iterator<iterator_t<_Tp>> && requires(_Tp& __t) {
+ { ranges::data(__t) } -> same_as<add_pointer_t<range_reference_t<_Tp>>>;
+};
+
+template <class _Tp>
+concept common_range = range<_Tp> && same_as<iterator_t<_Tp>, sentinel_t<_Tp>>;
+
+template <class _Tp>
+inline constexpr bool __is_std_initializer_list = false;
+
+template <class _Ep>
+inline constexpr bool __is_std_initializer_list<initializer_list<_Ep>> = true;
+
+template <class _Tp>
+concept viewable_range =
+ range<_Tp> &&
+ ((view<remove_cvref_t<_Tp>> && constructible_from<remove_cvref_t<_Tp>, _Tp>) ||
+ (!view<remove_cvref_t<_Tp>> &&
+ (is_lvalue_reference_v<_Tp> ||
+ (movable<remove_reference_t<_Tp>> && !__is_std_initializer_list<remove_cvref_t<_Tp>>))));
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_CONCEPTS_H
diff --git a/libcxx/include/__cxx03/__ranges/container_compatible_range.h b/libcxx/include/__cxx03/__ranges/container_compatible_range.h
new file mode 100644
index 00000000000000..a58f1119885e3e
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/container_compatible_range.h
@@ -0,0 +1,33 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_CONTAINER_COMPATIBLE_RANGE_H
+#define _LIBCPP___RANGES_CONTAINER_COMPATIBLE_RANGE_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__ranges/concepts.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Range, class _Tp>
+concept _ContainerCompatibleRange =
+ ranges::input_range<_Range> && convertible_to<ranges::range_reference_t<_Range>, _Tp>;
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_CONTAINER_COMPATIBLE_RANGE_H
diff --git a/libcxx/include/__cxx03/__ranges/counted.h b/libcxx/include/__cxx03/__ranges/counted.h
new file mode 100644
index 00000000000000..e365deca4e632d
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/counted.h
@@ -0,0 +1,89 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_COUNTED_H
+#define _LIBCPP___RANGES_COUNTED_H
+
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/counted_iterator.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__ranges/subrange.h>
+#include <__type_traits/decay.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <span>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges::views {
+
+namespace __counted {
+
+struct __fn {
+ template <contiguous_iterator _It>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto
+ __go(_It __it,
+ iter_difference_t<_It> __count) noexcept(noexcept(span(std::to_address(__it), static_cast<size_t>(__count))))
+ // Deliberately omit return-type SFINAE, because to_address is not SFINAE-friendly
+ {
+ return span(std::to_address(__it), static_cast<size_t>(__count));
+ }
+
+ template <random_access_iterator _It>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_It __it, iter_difference_t<_It> __count) noexcept(
+ noexcept(subrange(__it, __it + __count))) -> decltype(subrange(__it, __it + __count)) {
+ return subrange(__it, __it + __count);
+ }
+
+ template <class _It>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_It __it, iter_difference_t<_It> __count) noexcept(
+ noexcept(subrange(counted_iterator(std::move(__it), __count), default_sentinel)))
+ -> decltype(subrange(counted_iterator(std::move(__it), __count), default_sentinel)) {
+ return subrange(counted_iterator(std::move(__it), __count), default_sentinel);
+ }
+
+ template <class _It, convertible_to<iter_difference_t<_It>> _Diff>
+ requires input_or_output_iterator<decay_t<_It>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_It&& __it, _Diff&& __count) const
+ noexcept(noexcept(__go(std::forward<_It>(__it), std::forward<_Diff>(__count))))
+ -> decltype(__go(std::forward<_It>(__it), std::forward<_Diff>(__count))) {
+ return __go(std::forward<_It>(__it), std::forward<_Diff>(__count));
+ }
+};
+
+} // namespace __counted
+
+inline namespace __cpo {
+inline constexpr auto counted = __counted::__fn{};
+} // namespace __cpo
+
+} // namespace ranges::views
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_COUNTED_H
diff --git a/libcxx/include/__cxx03/__ranges/dangling.h b/libcxx/include/__cxx03/__ranges/dangling.h
new file mode 100644
index 00000000000000..613084d5fb9fc1
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/dangling.h
@@ -0,0 +1,42 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_DANGLING_H
+#define _LIBCPP___RANGES_DANGLING_H
+
+#include <__config>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/conditional.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+struct dangling {
+ dangling() = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr dangling(auto&&...) noexcept {}
+};
+
+template <range _Rp>
+using borrowed_iterator_t = _If<borrowed_range<_Rp>, iterator_t<_Rp>, dangling>;
+
+// borrowed_subrange_t defined in <__ranges/subrange.h>
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_DANGLING_H
diff --git a/libcxx/include/__cxx03/__ranges/data.h b/libcxx/include/__cxx03/__ranges/data.h
new file mode 100644
index 00000000000000..50db3cffeeed8a
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/data.h
@@ -0,0 +1,102 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_DATA_H
+#define _LIBCPP___RANGES_DATA_H
+
+#include <__concepts/class_or_enum.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__ranges/access.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_pointer.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/auto_cast.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [range.prim.data]
+
+namespace ranges {
+namespace __data {
+template <class _Tp>
+concept __ptr_to_object = is_pointer_v<_Tp> && is_object_v<remove_pointer_t<_Tp>>;
+
+template <class _Tp>
+concept __member_data = __can_borrow<_Tp> && requires(_Tp&& __t) {
+ { _LIBCPP_AUTO_CAST(__t.data()) } -> __ptr_to_object;
+};
+
+template <class _Tp>
+concept __ranges_begin_invocable = !__member_data<_Tp> && __can_borrow<_Tp> && requires(_Tp&& __t) {
+ { ranges::begin(__t) } -> contiguous_iterator;
+};
+
+struct __fn {
+ template <__member_data _Tp>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept(noexcept(__t.data())) {
+ return __t.data();
+ }
+
+ template <__ranges_begin_invocable _Tp>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(std::to_address(ranges::begin(__t)))) {
+ return std::to_address(ranges::begin(__t));
+ }
+};
+} // namespace __data
+
+inline namespace __cpo {
+inline constexpr auto data = __data::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+// [range.prim.cdata]
+
+namespace ranges {
+namespace __cdata {
+struct __fn {
+ template <class _Tp>
+ requires is_lvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::data(static_cast<const remove_reference_t<_Tp>&>(__t))))
+ -> decltype(ranges::data(static_cast<const remove_reference_t<_Tp>&>(__t))) {
+ return ranges::data(static_cast<const remove_reference_t<_Tp>&>(__t));
+ }
+
+ template <class _Tp>
+ requires is_rvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept(
+ noexcept(ranges::data(static_cast<const _Tp&&>(__t)))) -> decltype(ranges::data(static_cast<const _Tp&&>(__t))) {
+ return ranges::data(static_cast<const _Tp&&>(__t));
+ }
+};
+} // namespace __cdata
+
+inline namespace __cpo {
+inline constexpr auto cdata = __cdata::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_DATA_H
diff --git a/libcxx/include/__cxx03/__ranges/drop_view.h b/libcxx/include/__cxx03/__ranges/drop_view.h
new file mode 100644
index 00000000000000..853e22a402cad1
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/drop_view.h
@@ -0,0 +1,329 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_DROP_VIEW_H
+#define _LIBCPP___RANGES_DROP_VIEW_H
+
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__fwd/span.h>
+#include <__fwd/string_view.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/empty_view.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/iota_view.h>
+#include <__ranges/non_propagating_cache.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/repeat_view.h>
+#include <__ranges/size.h>
+#include <__ranges/subrange.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/auto_cast.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <view _View>
+class drop_view : public view_interface<drop_view<_View>> {
+ // We cache begin() whenever ranges::next is not guaranteed O(1) to provide an
+ // amortized O(1) begin() method. If this is an input_range, then we cannot cache
+ // begin because begin is not equality preserving.
+ // Note: drop_view<input-range>::begin() is still trivially amortized O(1) because
+ // one can't call begin() on it more than once.
+ static constexpr bool _UseCache = forward_range<_View> && !(random_access_range<_View> && sized_range<_View>);
+ using _Cache = _If<_UseCache, __non_propagating_cache<iterator_t<_View>>, __empty_cache>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Cache __cached_begin_ = _Cache();
+ range_difference_t<_View> __count_ = 0;
+ _View __base_ = _View();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI drop_view()
+ requires default_initializable<_View>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23
+ drop_view(_View __base, range_difference_t<_View> __count)
+ : __count_(__count), __base_(std::move(__base)) {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__count_ >= 0, "count must be greater than or equal to zero.");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
+ requires(!(__simple_view<_View> && random_access_range<const _View> && sized_range<const _View>))
+ {
+ if constexpr (random_access_range<_View> && sized_range<_View>) {
+ const auto __dist = std::min(ranges::distance(__base_), __count_);
+ return ranges::begin(__base_) + __dist;
+ }
+ if constexpr (_UseCache)
+ if (__cached_begin_.__has_value())
+ return *__cached_begin_;
+
+ auto __tmp = ranges::next(ranges::begin(__base_), __count_, ranges::end(__base_));
+ if constexpr (_UseCache)
+ __cached_begin_.__emplace(__tmp);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires random_access_range<const _View> && sized_range<const _View>
+ {
+ const auto __dist = std::min(ranges::distance(__base_), __count_);
+ return ranges::begin(__base_) + __dist;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end()
+ requires(!__simple_view<_View>)
+ {
+ return ranges::end(__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires range<const _View>
+ {
+ return ranges::end(__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __size(auto& __self) {
+ const auto __s = ranges::size(__self.__base_);
+ const auto __c = static_cast<decltype(__s)>(__self.__count_);
+ return __s < __c ? 0 : __s - __c;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires sized_range<_View>
+ {
+ return __size(*this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<const _View>
+ {
+ return __size(*this);
+ }
+};
+
+template <class _Range>
+drop_view(_Range&&, range_difference_t<_Range>) -> drop_view<views::all_t<_Range>>;
+
+template <class _Tp>
+inline constexpr bool enable_borrowed_range<drop_view<_Tp>> = enable_borrowed_range<_Tp>;
+
+namespace views {
+namespace __drop {
+
+template <class _Tp>
+inline constexpr bool __is_empty_view = false;
+
+template <class _Tp>
+inline constexpr bool __is_empty_view<empty_view<_Tp>> = true;
+
+template <class _Tp>
+inline constexpr bool __is_passthrough_specialization = false;
+
+template <class _Tp, size_t _Extent>
+inline constexpr bool __is_passthrough_specialization<span<_Tp, _Extent>> = true;
+
+template <class _CharT, class _Traits>
+inline constexpr bool __is_passthrough_specialization<basic_string_view<_CharT, _Traits>> = true;
+
+template <class _Np, class _Bound>
+inline constexpr bool __is_passthrough_specialization<iota_view<_Np, _Bound>> = true;
+
+template <class _Iter, class _Sent, subrange_kind _Kind>
+inline constexpr bool __is_passthrough_specialization<subrange<_Iter, _Sent, _Kind>> =
+ !subrange<_Iter, _Sent, _Kind>::_StoreSize;
+
+template <class _Tp>
+inline constexpr bool __is_subrange_specialization_with_store_size = false;
+
+template <class _Iter, class _Sent, subrange_kind _Kind>
+inline constexpr bool __is_subrange_specialization_with_store_size<subrange<_Iter, _Sent, _Kind>> =
+ subrange<_Iter, _Sent, _Kind>::_StoreSize;
+
+template <class _Tp>
+struct __passthrough_type;
+
+template <class _Tp, size_t _Extent>
+struct __passthrough_type<span<_Tp, _Extent>> {
+ using type = span<_Tp>;
+};
+
+template <class _CharT, class _Traits>
+struct __passthrough_type<basic_string_view<_CharT, _Traits>> {
+ using type = basic_string_view<_CharT, _Traits>;
+};
+
+template <class _Np, class _Bound>
+struct __passthrough_type<iota_view<_Np, _Bound>> {
+ using type = iota_view<_Np, _Bound>;
+};
+
+template <class _Iter, class _Sent, subrange_kind _Kind>
+struct __passthrough_type<subrange<_Iter, _Sent, _Kind>> {
+ using type = subrange<_Iter, _Sent, _Kind>;
+};
+
+template <class _Tp>
+using __passthrough_type_t = typename __passthrough_type<_Tp>::type;
+
+struct __fn {
+ // [range.drop.overview]: the `empty_view` case.
+ template <class _Range, convertible_to<range_difference_t<_Range>> _Np>
+ requires __is_empty_view<remove_cvref_t<_Range>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Np&&) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(std::forward<_Range>(__range))))
+ -> decltype(_LIBCPP_AUTO_CAST(std::forward<_Range>(__range))) {
+ return _LIBCPP_AUTO_CAST(std::forward<_Range>(__range));
+ }
+
+ // [range.drop.overview]: the `span | basic_string_view | iota_view | subrange (StoreSize == false)` case.
+ template <class _Range,
+ convertible_to<range_difference_t<_Range>> _Np,
+ class _RawRange = remove_cvref_t<_Range>,
+ class _Dist = range_difference_t<_Range>>
+ requires(!__is_empty_view<_RawRange> && random_access_range<_RawRange> && sized_range<_RawRange> &&
+ __is_passthrough_specialization<_RawRange>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __rng, _Np&& __n) const
+ noexcept(noexcept(__passthrough_type_t<_RawRange>(
+ ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)), ranges::end(__rng))))
+ -> decltype(__passthrough_type_t<_RawRange>(
+ // Note: deliberately not forwarding `__rng` to guard against double moves.
+ ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)),
+ ranges::end(__rng))) {
+ return __passthrough_type_t<_RawRange>(
+ ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)), ranges::end(__rng));
+ }
+
+ // [range.drop.overview]: the `subrange (StoreSize == true)` case.
+ template <class _Range,
+ convertible_to<range_difference_t<_Range>> _Np,
+ class _RawRange = remove_cvref_t<_Range>,
+ class _Dist = range_difference_t<_Range>>
+ requires(!__is_empty_view<_RawRange> && random_access_range<_RawRange> && sized_range<_RawRange> &&
+ __is_subrange_specialization_with_store_size<_RawRange>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __rng, _Np&& __n) const noexcept(noexcept(
+ _RawRange(ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)),
+ ranges::end(__rng),
+ std::__to_unsigned_like(ranges::distance(__rng) -
+ std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n))))))
+ -> decltype(_RawRange(
+ // Note: deliberately not forwarding `__rng` to guard against double moves.
+ ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)),
+ ranges::end(__rng),
+ std::__to_unsigned_like(ranges::distance(__rng) -
+ std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n))))) {
+ // Introducing local variables avoids calculating `min` and `distance` twice (at the cost of diverging from the
+ // expression used in the `noexcept` clause and the return statement).
+ auto __dist = ranges::distance(__rng);
+ auto __clamped = std::min<_Dist>(__dist, std::forward<_Np>(__n));
+ return _RawRange(ranges::begin(__rng) + __clamped, ranges::end(__rng), std::__to_unsigned_like(__dist - __clamped));
+ }
+ // clang-format off
+#if _LIBCPP_STD_VER >= 23
+ // [range.drop.overview]: the `repeat_view` "_RawRange models sized_range" case.
+ template <class _Range,
+ convertible_to<range_difference_t<_Range>> _Np,
+ class _RawRange = remove_cvref_t<_Range>,
+ class _Dist = range_difference_t<_Range>>
+ requires (__is_repeat_specialization<_RawRange> && sized_range<_RawRange>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Np&& __n) const
+ noexcept(noexcept(views::repeat(*__range.__value_, ranges::distance(__range) - std::min<_Dist>(ranges::distance(__range), std::forward<_Np>(__n)))))
+ -> decltype( views::repeat(*__range.__value_, ranges::distance(__range) - std::min<_Dist>(ranges::distance(__range), std::forward<_Np>(__n))))
+ { return views::repeat(*__range.__value_, ranges::distance(__range) - std::min<_Dist>(ranges::distance(__range), std::forward<_Np>(__n))); }
+
+ // [range.drop.overview]: the `repeat_view` "otherwise" case.
+ template <class _Range,
+ convertible_to<range_difference_t<_Range>> _Np,
+ class _RawRange = remove_cvref_t<_Range>,
+ class _Dist = range_difference_t<_Range>>
+ requires (__is_repeat_specialization<_RawRange> && !sized_range<_RawRange>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI
+ constexpr auto operator()(_Range&& __range, _Np&&) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(std::forward<_Range>(__range))))
+ -> decltype( _LIBCPP_AUTO_CAST(std::forward<_Range>(__range)))
+ { return _LIBCPP_AUTO_CAST(std::forward<_Range>(__range)); }
+#endif
+ // clang-format on
+
+ // [range.drop.overview]: the "otherwise" case.
+ template <class _Range, convertible_to<range_difference_t<_Range>> _Np, class _RawRange = remove_cvref_t<_Range>>
+ // Note: without specifically excluding the other cases, GCC sees this overload as ambiguous with the other
+ // overloads.
+ requires(!(__is_empty_view<_RawRange> ||
+# if _LIBCPP_STD_VER >= 23
+ __is_repeat_specialization<_RawRange> ||
+# endif
+ (__is_subrange_specialization_with_store_size<_RawRange> && sized_range<_RawRange> &&
+ random_access_range<_RawRange>) ||
+ (__is_passthrough_specialization<_RawRange> && sized_range<_RawRange> &&
+ random_access_range<_RawRange>)))
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Np&& __n) const
+ noexcept(noexcept(drop_view(std::forward<_Range>(__range), std::forward<_Np>(__n))))
+ -> decltype(drop_view(std::forward<_Range>(__range), std::forward<_Np>(__n))) {
+ return drop_view(std::forward<_Range>(__range), std::forward<_Np>(__n));
+ }
+
+ template <class _Np>
+ requires constructible_from<decay_t<_Np>, _Np>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Np&& __n) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Np>, _Np>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Np>(__n)));
+ }
+};
+
+} // namespace __drop
+
+inline namespace __cpo {
+inline constexpr auto drop = __drop::__fn{};
+} // namespace __cpo
+} // namespace views
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_DROP_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/drop_while_view.h b/libcxx/include/__cxx03/__ranges/drop_while_view.h
new file mode 100644
index 00000000000000..92f48bd0ecfba3
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/drop_while_view.h
@@ -0,0 +1,136 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_DROP_WHILE_VIEW_H
+#define _LIBCPP___RANGES_DROP_WHILE_VIEW_H
+
+#include <__algorithm/ranges_find_if_not.h>
+#include <__assert>
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__functional/reference_wrapper.h>
+#include <__iterator/concepts.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/movable_box.h>
+#include <__ranges/non_propagating_cache.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_object.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <view _View, class _Pred>
+ requires input_range<_View> && is_object_v<_Pred> && indirect_unary_predicate<const _Pred, iterator_t<_View>>
+class _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS drop_while_view : public view_interface<drop_while_view<_View, _Pred>> {
+public:
+ _LIBCPP_HIDE_FROM_ABI drop_while_view()
+ requires default_initializable<_View> && default_initializable<_Pred>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 drop_while_view(_View __base, _Pred __pred)
+ : __base_(std::move(__base)), __pred_(std::in_place, std::move(__pred)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Pred& pred() const { return *__pred_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() {
+ // Note: this duplicates a check in `optional` but provides a better error message.
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __pred_.__has_value(),
+ "drop_while_view needs to have a non-empty predicate before calling begin() -- did a previous "
+ "assignment to this drop_while_view fail?");
+ if constexpr (_UseCache) {
+ if (!__cached_begin_.__has_value()) {
+ __cached_begin_.__emplace(ranges::find_if_not(__base_, std::cref(*__pred_)));
+ }
+ return *__cached_begin_;
+ } else {
+ return ranges::find_if_not(__base_, std::cref(*__pred_));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() { return ranges::end(__base_); }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+ _LIBCPP_NO_UNIQUE_ADDRESS __movable_box<_Pred> __pred_;
+
+ static constexpr bool _UseCache = forward_range<_View>;
+ using _Cache = _If<_UseCache, __non_propagating_cache<iterator_t<_View>>, __empty_cache>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Cache __cached_begin_ = _Cache();
+};
+
+template <class _View, class _Pred>
+inline constexpr bool enable_borrowed_range<drop_while_view<_View, _Pred>> = enable_borrowed_range<_View>;
+
+template <class _Range, class _Pred>
+drop_while_view(_Range&&, _Pred) -> drop_while_view<views::all_t<_Range>, _Pred>;
+
+namespace views {
+namespace __drop_while {
+
+struct __fn {
+ template <class _Range, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Pred&& __pred) const
+ noexcept(noexcept(/**/ drop_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))))
+ -> decltype(/*--*/ drop_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))) {
+ return /*-------------*/ drop_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred));
+ }
+
+ template <class _Pred>
+ requires constructible_from<decay_t<_Pred>, _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Pred&& __pred) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Pred>, _Pred>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Pred>(__pred)));
+ }
+};
+
+} // namespace __drop_while
+
+inline namespace __cpo {
+inline constexpr auto drop_while = __drop_while::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_DROP_WHILE_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/elements_view.h b/libcxx/include/__cxx03/__ranges/elements_view.h
new file mode 100644
index 00000000000000..f159f53dc0a832
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/elements_view.h
@@ -0,0 +1,418 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_ELEMENTS_VIEW_H
+#define _LIBCPP___RANGES_ELEMENTS_VIEW_H
+
+#include <__compare/three_way_comparable.h>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/equality_comparable.h>
+#include <__config>
+#include <__fwd/complex.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/size.h>
+#include <__ranges/view_interface.h>
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_like.h>
+#include <__tuple/tuple_size.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/maybe_const.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _Tp, size_t _Np>
+concept __has_tuple_element = __tuple_like<_Tp> && _Np < tuple_size<_Tp>::value;
+
+template <class _Tp, size_t _Np>
+concept __returnable_element = is_reference_v<_Tp> || move_constructible<tuple_element_t<_Np, _Tp>>;
+
+template <input_range _View, size_t _Np>
+ requires view<_View> && __has_tuple_element<range_value_t<_View>, _Np> &&
+ __has_tuple_element<remove_reference_t<range_reference_t<_View>>, _Np> &&
+ __returnable_element<range_reference_t<_View>, _Np>
+class elements_view : public view_interface<elements_view<_View, _Np>> {
+private:
+ template <bool>
+ class __iterator;
+
+ template <bool>
+ class __sentinel;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI elements_view()
+ requires default_initializable<_View>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit elements_view(_View __base) : __base_(std::move(__base)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
+ requires(!__simple_view<_View>)
+ {
+ return __iterator</*_Const=*/false>(ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires range<const _View>
+ {
+ return __iterator</*_Const=*/true>(ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end()
+ requires(!__simple_view<_View> && !common_range<_View>)
+ {
+ return __sentinel</*_Const=*/false>{ranges::end(__base_)};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end()
+ requires(!__simple_view<_View> && common_range<_View>)
+ {
+ return __iterator</*_Const=*/false>{ranges::end(__base_)};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires range<const _View>
+ {
+ return __sentinel</*_Const=*/true>{ranges::end(__base_)};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires common_range<const _View>
+ {
+ return __iterator</*_Const=*/true>{ranges::end(__base_)};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires sized_range<_View>
+ {
+ return ranges::size(__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<const _View>
+ {
+ return ranges::size(__base_);
+ }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+};
+
+template <class, size_t>
+struct __elements_view_iterator_category_base {};
+
+template <forward_range _Base, size_t _Np>
+struct __elements_view_iterator_category_base<_Base, _Np> {
+ static consteval auto __get_iterator_category() {
+ using _Result = decltype(std::get<_Np>(*std::declval<iterator_t<_Base>>()));
+ using _Cat = typename iterator_traits<iterator_t<_Base>>::iterator_category;
+
+ if constexpr (!is_lvalue_reference_v<_Result>) {
+ return input_iterator_tag{};
+ } else if constexpr (derived_from<_Cat, random_access_iterator_tag>) {
+ return random_access_iterator_tag{};
+ } else {
+ return _Cat{};
+ }
+ }
+
+ using iterator_category = decltype(__get_iterator_category());
+};
+
+template <input_range _View, size_t _Np>
+ requires view<_View> && __has_tuple_element<range_value_t<_View>, _Np> &&
+ __has_tuple_element<remove_reference_t<range_reference_t<_View>>, _Np> &&
+ __returnable_element<range_reference_t<_View>, _Np>
+template <bool _Const>
+class elements_view<_View, _Np>::__iterator
+ : public __elements_view_iterator_category_base<__maybe_const<_Const, _View>, _Np> {
+ template <bool>
+ friend class __iterator;
+
+ template <bool>
+ friend class __sentinel;
+
+ using _Base = __maybe_const<_Const, _View>;
+
+ iterator_t<_Base> __current_ = iterator_t<_Base>();
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto) __get_element(const iterator_t<_Base>& __i) {
+ if constexpr (is_reference_v<range_reference_t<_Base>>) {
+ return std::get<_Np>(*__i);
+ } else {
+ using _Element = remove_cv_t<tuple_element_t<_Np, range_reference_t<_Base>>>;
+ return static_cast<_Element>(std::get<_Np>(*__i));
+ }
+ }
+
+ static consteval auto __get_iterator_concept() {
+ if constexpr (random_access_range<_Base>) {
+ return random_access_iterator_tag{};
+ } else if constexpr (bidirectional_range<_Base>) {
+ return bidirectional_iterator_tag{};
+ } else if constexpr (forward_range<_Base>) {
+ return forward_iterator_tag{};
+ } else {
+ return input_iterator_tag{};
+ }
+ }
+
+public:
+ using iterator_concept = decltype(__get_iterator_concept());
+ using value_type = remove_cvref_t<tuple_element_t<_Np, range_value_t<_Base>>>;
+ using difference_type = range_difference_t<_Base>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator()
+ requires default_initializable<iterator_t<_Base>>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(iterator_t<_Base> __current) : __current_(std::move(__current)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(__iterator<!_Const> __i)
+ requires _Const && convertible_to<iterator_t<_View>, iterator_t<_Base>>
+ : __current_(std::move(__i.__current_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const iterator_t<_Base>& base() const& noexcept { return __current_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_Base> base() && { return std::move(__current_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const { return __get_element(__current_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ ++__current_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator++(int) { ++__current_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int)
+ requires forward_range<_Base>
+ {
+ auto __temp = *this;
+ ++__current_;
+ return __temp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--()
+ requires bidirectional_range<_Base>
+ {
+ --__current_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int)
+ requires bidirectional_range<_Base>
+ {
+ auto __temp = *this;
+ --__current_;
+ return __temp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator+=(difference_type __n)
+ requires random_access_range<_Base>
+ {
+ __current_ += __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator-=(difference_type __n)
+ requires random_access_range<_Base>
+ {
+ __current_ -= __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator[](difference_type __n) const
+ requires random_access_range<_Base>
+ {
+ return __get_element(__current_ + __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
+ requires equality_comparable<iterator_t<_Base>>
+ {
+ return __x.__current_ == __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return __x.__current_ < __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return __y < __x;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return !(__y < __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return !(__x < __y);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base> && three_way_comparable<iterator_t<_Base>>
+ {
+ return __x.__current_ <=> __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(const __iterator& __x, difference_type __y)
+ requires random_access_range<_Base>
+ {
+ return __iterator{__x} += __y;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(difference_type __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return __y + __x;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator-(const __iterator& __x, difference_type __y)
+ requires random_access_range<_Base>
+ {
+ return __iterator{__x} -= __y;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y)
+ requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>>
+ {
+ return __x.__current_ - __y.__current_;
+ }
+};
+
+template <input_range _View, size_t _Np>
+ requires view<_View> && __has_tuple_element<range_value_t<_View>, _Np> &&
+ __has_tuple_element<remove_reference_t<range_reference_t<_View>>, _Np> &&
+ __returnable_element<range_reference_t<_View>, _Np>
+template <bool _Const>
+class elements_view<_View, _Np>::__sentinel {
+private:
+ using _Base = __maybe_const<_Const, _View>;
+ _LIBCPP_NO_UNIQUE_ADDRESS sentinel_t<_Base> __end_ = sentinel_t<_Base>();
+
+ template <bool>
+ friend class __sentinel;
+
+ template <bool _AnyConst>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto) __get_current(const __iterator<_AnyConst>& __iter) {
+ return (__iter.__current_);
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(sentinel_t<_Base> __end) : __end_(std::move(__end)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __other)
+ requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
+ : __end_(std::move(__other.__end_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Base> base() const { return __end_; }
+
+ template <bool _OtherConst>
+ requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
+ return __get_current(__x) == __y.__end_;
+ }
+
+ template <bool _OtherConst>
+ requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr range_difference_t<__maybe_const<_OtherConst, _View>>
+ operator-(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
+ return __get_current(__x) - __y.__end_;
+ }
+
+ template <bool _OtherConst>
+ requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr range_difference_t<__maybe_const<_OtherConst, _View>>
+ operator-(const __sentinel& __x, const __iterator<_OtherConst>& __y) {
+ return __x.__end_ - __get_current(__y);
+ }
+};
+
+template <class _Tp, size_t _Np>
+inline constexpr bool enable_borrowed_range<elements_view<_Tp, _Np>> = enable_borrowed_range<_Tp>;
+
+template <class _Tp>
+using keys_view = elements_view<_Tp, 0>;
+template <class _Tp>
+using values_view = elements_view<_Tp, 1>;
+
+namespace views {
+namespace __elements {
+
+template <size_t _Np>
+struct __fn : __range_adaptor_closure<__fn<_Np>> {
+ template <class _Range>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
+ /**/ noexcept(noexcept(elements_view<all_t<_Range&&>, _Np>(std::forward<_Range>(__range))))
+ /*------*/ -> decltype(elements_view<all_t<_Range&&>, _Np>(std::forward<_Range>(__range))) {
+ /*-------------*/ return elements_view<all_t<_Range&&>, _Np>(std::forward<_Range>(__range));
+ }
+};
+} // namespace __elements
+
+inline namespace __cpo {
+template <size_t _Np>
+inline constexpr auto elements = __elements::__fn<_Np>{};
+inline constexpr auto keys = elements<0>;
+inline constexpr auto values = elements<1>;
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_ELEMENTS_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/empty.h b/libcxx/include/__cxx03/__ranges/empty.h
new file mode 100644
index 00000000000000..5c1004042aba51
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/empty.h
@@ -0,0 +1,71 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_EMPTY_H
+#define _LIBCPP___RANGES_EMPTY_H
+
+#include <__concepts/class_or_enum.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__ranges/access.h>
+#include <__ranges/size.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [range.prim.empty]
+
+namespace ranges {
+namespace __empty {
+template <class _Tp>
+concept __member_empty = requires(_Tp&& __t) { bool(__t.empty()); };
+
+template <class _Tp>
+concept __can_invoke_size = !__member_empty<_Tp> && requires(_Tp&& __t) { ranges::size(__t); };
+
+template <class _Tp>
+concept __can_compare_begin_end = !__member_empty<_Tp> && !__can_invoke_size<_Tp> && requires(_Tp&& __t) {
+ bool(ranges::begin(__t) == ranges::end(__t));
+ { ranges::begin(__t) } -> forward_iterator;
+};
+
+struct __fn {
+ template <__member_empty _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t) const noexcept(noexcept(bool(__t.empty()))) {
+ return bool(__t.empty());
+ }
+
+ template <__can_invoke_size _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t) const noexcept(noexcept(ranges::size(__t))) {
+ return ranges::size(__t) == 0;
+ }
+
+ template <__can_compare_begin_end _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t) const
+ noexcept(noexcept(bool(ranges::begin(__t) == ranges::end(__t)))) {
+ return ranges::begin(__t) == ranges::end(__t);
+ }
+};
+} // namespace __empty
+
+inline namespace __cpo {
+inline constexpr auto empty = __empty::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_EMPTY_H
diff --git a/libcxx/include/__cxx03/__ranges/empty_view.h b/libcxx/include/__cxx03/__ranges/empty_view.h
new file mode 100644
index 00000000000000..6c04b0200c35f2
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/empty_view.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_EMPTY_VIEW_H
+#define _LIBCPP___RANGES_EMPTY_VIEW_H
+
+#include <__config>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/is_object.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <class _Tp>
+ requires is_object_v<_Tp>
+class empty_view : public view_interface<empty_view<_Tp>> {
+public:
+ _LIBCPP_HIDE_FROM_ABI static constexpr _Tp* begin() noexcept { return nullptr; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr _Tp* end() noexcept { return nullptr; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr _Tp* data() noexcept { return nullptr; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t size() noexcept { return 0; }
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool empty() noexcept { return true; }
+};
+
+template <class _Tp>
+inline constexpr bool enable_borrowed_range<empty_view<_Tp>> = true;
+
+namespace views {
+
+template <class _Tp>
+inline constexpr empty_view<_Tp> empty{};
+
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_EMPTY_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/enable_borrowed_range.h b/libcxx/include/__cxx03/__ranges/enable_borrowed_range.h
new file mode 100644
index 00000000000000..1d068335e20af2
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/enable_borrowed_range.h
@@ -0,0 +1,40 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_ENABLE_BORROWED_RANGE_H
+#define _LIBCPP___RANGES_ENABLE_BORROWED_RANGE_H
+
+// These customization variables are used in <span> and <string_view>. The
+// separate header is used to avoid including the entire <ranges> header in
+// <span> and <string_view>.
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+// [range.range], ranges
+
+template <class>
+inline constexpr bool enable_borrowed_range = false;
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_ENABLE_BORROWED_RANGE_H
diff --git a/libcxx/include/__cxx03/__ranges/enable_view.h b/libcxx/include/__cxx03/__ranges/enable_view.h
new file mode 100644
index 00000000000000..f570926eb67c34
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/enable_view.h
@@ -0,0 +1,51 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_ENABLE_VIEW_H
+#define _LIBCPP___RANGES_ENABLE_VIEW_H
+
+#include <__concepts/derived_from.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__type_traits/is_class.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+struct view_base {};
+
+template <class _Derived>
+ requires is_class_v<_Derived> && same_as<_Derived, remove_cv_t<_Derived>>
+class view_interface;
+
+template <class _Op, class _Yp>
+ requires is_convertible_v<_Op*, view_interface<_Yp>*>
+void __is_derived_from_view_interface(const _Op*, const view_interface<_Yp>*);
+
+template <class _Tp>
+inline constexpr bool enable_view = derived_from<_Tp, view_base> || requires {
+ ranges::__is_derived_from_view_interface((_Tp*)nullptr, (_Tp*)nullptr);
+};
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_ENABLE_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/filter_view.h b/libcxx/include/__cxx03/__ranges/filter_view.h
new file mode 100644
index 00000000000000..5b938dd4c16e19
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/filter_view.h
@@ -0,0 +1,260 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_FILTER_VIEW_H
+#define _LIBCPP___RANGES_FILTER_VIEW_H
+
+#include <__algorithm/ranges_find_if.h>
+#include <__assert>
+#include <__concepts/constructible.h>
+#include <__concepts/copyable.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/equality_comparable.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__functional/invoke.h>
+#include <__functional/reference_wrapper.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/movable_box.h>
+#include <__ranges/non_propagating_cache.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_object.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <input_range _View, indirect_unary_predicate<iterator_t<_View>> _Pred>
+ requires view<_View> && is_object_v<_Pred>
+class _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS filter_view : public view_interface<filter_view<_View, _Pred>> {
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+ _LIBCPP_NO_UNIQUE_ADDRESS __movable_box<_Pred> __pred_;
+
+ // We cache the result of begin() to allow providing an amortized O(1) begin() whenever
+ // the underlying range is at least a forward_range.
+ static constexpr bool _UseCache = forward_range<_View>;
+ using _Cache = _If<_UseCache, __non_propagating_cache<iterator_t<_View>>, __empty_cache>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Cache __cached_begin_ = _Cache();
+
+ class __iterator;
+ class __sentinel;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI filter_view()
+ requires default_initializable<_View> && default_initializable<_Pred>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 filter_view(_View __base, _Pred __pred)
+ : __base_(std::move(__base)), __pred_(in_place, std::move(__pred)) {}
+
+ template <class _Vp = _View>
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_Vp>
+ {
+ return __base_;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Pred const& pred() const { return *__pred_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator begin() {
+ // Note: this duplicates a check in `optional` but provides a better error message.
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __pred_.__has_value(), "Trying to call begin() on a filter_view that does not have a valid predicate.");
+ if constexpr (_UseCache) {
+ if (!__cached_begin_.__has_value()) {
+ __cached_begin_.__emplace(ranges::find_if(__base_, std::ref(*__pred_)));
+ }
+ return {*this, *__cached_begin_};
+ } else {
+ return {*this, ranges::find_if(__base_, std::ref(*__pred_))};
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() {
+ if constexpr (common_range<_View>)
+ return __iterator{*this, ranges::end(__base_)};
+ else
+ return __sentinel{*this};
+ }
+};
+
+template <class _Range, class _Pred>
+filter_view(_Range&&, _Pred) -> filter_view<views::all_t<_Range>, _Pred>;
+
+template <class _View>
+struct __filter_iterator_category {};
+
+template <forward_range _View>
+struct __filter_iterator_category<_View> {
+ using _Cat = typename iterator_traits<iterator_t<_View>>::iterator_category;
+ using iterator_category =
+ _If<derived_from<_Cat, bidirectional_iterator_tag>,
+ bidirectional_iterator_tag,
+ _If<derived_from<_Cat, forward_iterator_tag>,
+ forward_iterator_tag,
+ /* else */ _Cat >>;
+};
+
+template <input_range _View, indirect_unary_predicate<iterator_t<_View>> _Pred>
+ requires view<_View> && is_object_v<_Pred>
+class filter_view<_View, _Pred>::__iterator : public __filter_iterator_category<_View> {
+public:
+ _LIBCPP_NO_UNIQUE_ADDRESS iterator_t<_View> __current_ = iterator_t<_View>();
+ _LIBCPP_NO_UNIQUE_ADDRESS filter_view* __parent_ = nullptr;
+
+ using iterator_concept =
+ _If<bidirectional_range<_View>,
+ bidirectional_iterator_tag,
+ _If<forward_range<_View>,
+ forward_iterator_tag,
+ /* else */ input_iterator_tag >>;
+ // using iterator_category = inherited;
+ using value_type = range_value_t<_View>;
+ using difference_type = range_difference_t<_View>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator()
+ requires default_initializable<iterator_t<_View>>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(filter_view& __parent, iterator_t<_View> __current)
+ : __current_(std::move(__current)), __parent_(std::addressof(__parent)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_View> const& base() const& noexcept { return __current_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_View> base() && { return std::move(__current_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr range_reference_t<_View> operator*() const { return *__current_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_View> operator->() const
+ requires __has_arrow<iterator_t<_View>> && copyable<iterator_t<_View>>
+ {
+ return __current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ __current_ =
+ ranges::find_if(std::move(++__current_), ranges::end(__parent_->__base_), std::ref(*__parent_->__pred_));
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator++(int) { ++*this; }
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int)
+ requires forward_range<_View>
+ {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--()
+ requires bidirectional_range<_View>
+ {
+ do {
+ --__current_;
+ } while (!std::invoke(*__parent_->__pred_, *__current_));
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int)
+ requires bidirectional_range<_View>
+ {
+ auto __tmp = *this;
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(__iterator const& __x, __iterator const& __y)
+ requires equality_comparable<iterator_t<_View>>
+ {
+ return __x.__current_ == __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr range_rvalue_reference_t<_View>
+ iter_move(__iterator const& __it) noexcept(noexcept(ranges::iter_move(__it.__current_))) {
+ return ranges::iter_move(__it.__current_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void
+ iter_swap(__iterator const& __x,
+ __iterator const& __y) noexcept(noexcept(ranges::iter_swap(__x.__current_, __y.__current_)))
+ requires indirectly_swappable<iterator_t<_View>>
+ {
+ return ranges::iter_swap(__x.__current_, __y.__current_);
+ }
+};
+
+template <input_range _View, indirect_unary_predicate<iterator_t<_View>> _Pred>
+ requires view<_View> && is_object_v<_Pred>
+class filter_view<_View, _Pred>::__sentinel {
+public:
+ sentinel_t<_View> __end_ = sentinel_t<_View>();
+
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(filter_view& __parent) : __end_(ranges::end(__parent.__base_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_View> base() const { return __end_; }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(__iterator const& __x, __sentinel const& __y) {
+ return __x.__current_ == __y.__end_;
+ }
+};
+
+namespace views {
+namespace __filter {
+struct __fn {
+ template <class _Range, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Pred&& __pred) const
+ noexcept(noexcept(filter_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))))
+ -> decltype(filter_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))) {
+ return filter_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred));
+ }
+
+ template <class _Pred>
+ requires constructible_from<decay_t<_Pred>, _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Pred&& __pred) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Pred>, _Pred>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Pred>(__pred)));
+ }
+};
+} // namespace __filter
+
+inline namespace __cpo {
+inline constexpr auto filter = __filter::__fn{};
+} // namespace __cpo
+} // namespace views
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_FILTER_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/from_range.h b/libcxx/include/__cxx03/__ranges/from_range.h
new file mode 100644
index 00000000000000..a6cb9e3d439ebf
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/from_range.h
@@ -0,0 +1,33 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_FROM_RANGE_H
+#define _LIBCPP___RANGES_FROM_RANGE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+struct from_range_t {
+ explicit from_range_t() = default;
+};
+
+inline constexpr from_range_t from_range{};
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_FROM_RANGE_H
diff --git a/libcxx/include/__cxx03/__ranges/iota_view.h b/libcxx/include/__cxx03/__ranges/iota_view.h
new file mode 100644
index 00000000000000..b2fa958a0f56e0
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/iota_view.h
@@ -0,0 +1,404 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_IOTA_VIEW_H
+#define _LIBCPP___RANGES_IOTA_VIEW_H
+
+#include <__assert>
+#include <__compare/three_way_comparable.h>
+#include <__concepts/arithmetic.h>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/copyable.h>
+#include <__concepts/equality_comparable.h>
+#include <__concepts/invocable.h>
+#include <__concepts/same_as.h>
+#include <__concepts/semiregular.h>
+#include <__concepts/totally_ordered.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/unreachable_sentinel.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/movable_box.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <class _Int>
+struct __get_wider_signed {
+ consteval static auto __call() {
+ if constexpr (sizeof(_Int) < sizeof(short))
+ return type_identity<short>{};
+ else if constexpr (sizeof(_Int) < sizeof(int))
+ return type_identity<int>{};
+ else if constexpr (sizeof(_Int) < sizeof(long))
+ return type_identity<long>{};
+ else
+ return type_identity<long long>{};
+
+ static_assert(
+ sizeof(_Int) <= sizeof(long long), "Found integer-like type that is bigger than largest integer like type.");
+ }
+
+ using type = typename decltype(__call())::type;
+};
+
+template <class _Start>
+using _IotaDiffT =
+ typename _If< (!integral<_Start> || sizeof(iter_difference_t<_Start>) > sizeof(_Start)),
+ type_identity<iter_difference_t<_Start>>,
+ __get_wider_signed<_Start> >::type;
+
+template <class _Iter>
+concept __decrementable = incrementable<_Iter> && requires(_Iter __i) {
+ { --__i } -> same_as<_Iter&>;
+ { __i-- } -> same_as<_Iter>;
+};
+
+template <class _Iter>
+concept __advanceable =
+ __decrementable<_Iter> && totally_ordered<_Iter> &&
+ requires(_Iter __i, const _Iter __j, const _IotaDiffT<_Iter> __n) {
+ { __i += __n } -> same_as<_Iter&>;
+ { __i -= __n } -> same_as<_Iter&>;
+ _Iter(__j + __n);
+ _Iter(__n + __j);
+ _Iter(__j - __n);
+ { __j - __j } -> convertible_to<_IotaDiffT<_Iter>>;
+ };
+
+template <class>
+struct __iota_iterator_category {};
+
+template <incrementable _Tp>
+struct __iota_iterator_category<_Tp> {
+ using iterator_category = input_iterator_tag;
+};
+
+template <weakly_incrementable _Start, semiregular _BoundSentinel = unreachable_sentinel_t>
+ requires __weakly_equality_comparable_with<_Start, _BoundSentinel> && copyable<_Start>
+class iota_view : public view_interface<iota_view<_Start, _BoundSentinel>> {
+ struct __iterator : public __iota_iterator_category<_Start> {
+ friend class iota_view;
+
+ using iterator_concept =
+ _If<__advanceable<_Start>,
+ random_access_iterator_tag,
+ _If<__decrementable<_Start>,
+ bidirectional_iterator_tag,
+ _If<incrementable<_Start>,
+ forward_iterator_tag,
+ /*Else*/ input_iterator_tag>>>;
+
+ using value_type = _Start;
+ using difference_type = _IotaDiffT<_Start>;
+
+ _Start __value_ = _Start();
+
+ _LIBCPP_HIDE_FROM_ABI __iterator()
+ requires default_initializable<_Start>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(_Start __value) : __value_(std::move(__value)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Start operator*() const noexcept(is_nothrow_copy_constructible_v<_Start>) {
+ return __value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ ++__value_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator++(int) { ++*this; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int)
+ requires incrementable<_Start>
+ {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--()
+ requires __decrementable<_Start>
+ {
+ --__value_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int)
+ requires __decrementable<_Start>
+ {
+ auto __tmp = *this;
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator+=(difference_type __n)
+ requires __advanceable<_Start>
+ {
+ if constexpr (__integer_like<_Start> && !__signed_integer_like<_Start>) {
+ if (__n >= difference_type(0)) {
+ __value_ += static_cast<_Start>(__n);
+ } else {
+ __value_ -= static_cast<_Start>(-__n);
+ }
+ } else {
+ __value_ += __n;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator-=(difference_type __n)
+ requires __advanceable<_Start>
+ {
+ if constexpr (__integer_like<_Start> && !__signed_integer_like<_Start>) {
+ if (__n >= difference_type(0)) {
+ __value_ -= static_cast<_Start>(__n);
+ } else {
+ __value_ += static_cast<_Start>(-__n);
+ }
+ } else {
+ __value_ -= __n;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Start operator[](difference_type __n) const
+ requires __advanceable<_Start>
+ {
+ return _Start(__value_ + __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
+ requires equality_comparable<_Start>
+ {
+ return __x.__value_ == __y.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(const __iterator& __x, const __iterator& __y)
+ requires totally_ordered<_Start>
+ {
+ return __x.__value_ < __y.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(const __iterator& __x, const __iterator& __y)
+ requires totally_ordered<_Start>
+ {
+ return __y < __x;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(const __iterator& __x, const __iterator& __y)
+ requires totally_ordered<_Start>
+ {
+ return !(__y < __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(const __iterator& __x, const __iterator& __y)
+ requires totally_ordered<_Start>
+ {
+ return !(__x < __y);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y)
+ requires totally_ordered<_Start> && three_way_comparable<_Start>
+ {
+ return __x.__value_ <=> __y.__value_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(__iterator __i, difference_type __n)
+ requires __advanceable<_Start>
+ {
+ __i += __n;
+ return __i;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(difference_type __n, __iterator __i)
+ requires __advanceable<_Start>
+ {
+ return __i + __n;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator-(__iterator __i, difference_type __n)
+ requires __advanceable<_Start>
+ {
+ __i -= __n;
+ return __i;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y)
+ requires __advanceable<_Start>
+ {
+ if constexpr (__integer_like<_Start>) {
+ if constexpr (__signed_integer_like<_Start>) {
+ return difference_type(difference_type(__x.__value_) - difference_type(__y.__value_));
+ }
+ if (__y.__value_ > __x.__value_) {
+ return difference_type(-difference_type(__y.__value_ - __x.__value_));
+ }
+ return difference_type(__x.__value_ - __y.__value_);
+ }
+ return __x.__value_ - __y.__value_;
+ }
+ };
+
+ struct __sentinel {
+ friend class iota_view;
+
+ private:
+ _BoundSentinel __bound_sentinel_ = _BoundSentinel();
+
+ public:
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(_BoundSentinel __bound_sentinel)
+ : __bound_sentinel_(std::move(__bound_sentinel)) {}
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __sentinel& __y) {
+ return __x.__value_ == __y.__bound_sentinel_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_Start>
+ operator-(const __iterator& __x, const __sentinel& __y)
+ requires sized_sentinel_for<_BoundSentinel, _Start>
+ {
+ return __x.__value_ - __y.__bound_sentinel_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_Start>
+ operator-(const __sentinel& __x, const __iterator& __y)
+ requires sized_sentinel_for<_BoundSentinel, _Start>
+ {
+ return -(__y - __x);
+ }
+ };
+
+ _Start __value_ = _Start();
+ _BoundSentinel __bound_sentinel_ = _BoundSentinel();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI iota_view()
+ requires default_initializable<_Start>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit iota_view(_Start __value) : __value_(std::move(__value)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23
+ iota_view(type_identity_t<_Start> __value, type_identity_t<_BoundSentinel> __bound_sentinel)
+ : __value_(std::move(__value)), __bound_sentinel_(std::move(__bound_sentinel)) {
+ // Validate the precondition if possible.
+ if constexpr (totally_ordered_with<_Start, _BoundSentinel>) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(
+ bool(__value_ <= __bound_sentinel_), "iota_view: bound must be reachable from value");
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 iota_view(__iterator __first, __iterator __last)
+ requires same_as<_Start, _BoundSentinel>
+ : iota_view(std::move(__first.__value_), std::move(__last.__value_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 iota_view(__iterator __first, _BoundSentinel __last)
+ requires same_as<_BoundSentinel, unreachable_sentinel_t>
+ : iota_view(std::move(__first.__value_), std::move(__last)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 iota_view(__iterator __first, __sentinel __last)
+ requires(!same_as<_Start, _BoundSentinel> && !same_as<_BoundSentinel, unreachable_sentinel_t>)
+ : iota_view(std::move(__first.__value_), std::move(__last.__bound_sentinel_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator begin() const { return __iterator{__value_}; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const {
+ if constexpr (same_as<_BoundSentinel, unreachable_sentinel_t>)
+ return unreachable_sentinel;
+ else
+ return __sentinel{__bound_sentinel_};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator end() const
+ requires same_as<_Start, _BoundSentinel>
+ {
+ return __iterator{__bound_sentinel_};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const { return __value_ == __bound_sentinel_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires(same_as<_Start, _BoundSentinel> && __advanceable<_Start>) ||
+ (integral<_Start> && integral<_BoundSentinel>) || sized_sentinel_for<_BoundSentinel, _Start>
+ {
+ if constexpr (__integer_like<_Start> && __integer_like<_BoundSentinel>) {
+ return (__value_ < 0)
+ ? ((__bound_sentinel_ < 0)
+ ? std::__to_unsigned_like(-__value_) - std::__to_unsigned_like(-__bound_sentinel_)
+ : std::__to_unsigned_like(__bound_sentinel_) + std::__to_unsigned_like(-__value_))
+ : std::__to_unsigned_like(__bound_sentinel_) - std::__to_unsigned_like(__value_);
+ } else {
+ return std::__to_unsigned_like(__bound_sentinel_ - __value_);
+ }
+ }
+};
+
+template <class _Start, class _BoundSentinel>
+ requires(!__integer_like<_Start> || !__integer_like<_BoundSentinel> ||
+ (__signed_integer_like<_Start> == __signed_integer_like<_BoundSentinel>))
+iota_view(_Start, _BoundSentinel) -> iota_view<_Start, _BoundSentinel>;
+
+template <class _Start, class _BoundSentinel>
+inline constexpr bool enable_borrowed_range<iota_view<_Start, _BoundSentinel>> = true;
+
+namespace views {
+namespace __iota {
+struct __fn {
+ template <class _Start>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Start&& __start) const
+ noexcept(noexcept(ranges::iota_view(std::forward<_Start>(__start))))
+ -> decltype(ranges::iota_view(std::forward<_Start>(__start))) {
+ return ranges::iota_view(std::forward<_Start>(__start));
+ }
+
+ template <class _Start, class _BoundSentinel>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Start&& __start, _BoundSentinel&& __bound_sentinel) const noexcept(
+ noexcept(ranges::iota_view(std::forward<_Start>(__start), std::forward<_BoundSentinel>(__bound_sentinel))))
+ -> decltype(ranges::iota_view(std::forward<_Start>(__start), std::forward<_BoundSentinel>(__bound_sentinel))) {
+ return ranges::iota_view(std::forward<_Start>(__start), std::forward<_BoundSentinel>(__bound_sentinel));
+ }
+};
+} // namespace __iota
+
+inline namespace __cpo {
+inline constexpr auto iota = __iota::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_IOTA_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/istream_view.h b/libcxx/include/__cxx03/__ranges/istream_view.h
new file mode 100644
index 00000000000000..cd7096d35c2c1f
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/istream_view.h
@@ -0,0 +1,141 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_ISTREAM_VIEW_H
+#define _LIBCPP___RANGES_ISTREAM_VIEW_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/movable.h>
+#include <__config>
+#include <__fwd/istream.h>
+#include <__fwd/string.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Val, class _CharT, class _Traits>
+concept __stream_extractable = requires(basic_istream<_CharT, _Traits>& __is, _Val& __t) { __is >> __t; };
+
+template <movable _Val, class _CharT, class _Traits = char_traits<_CharT>>
+ requires default_initializable<_Val> && __stream_extractable<_Val, _CharT, _Traits>
+class basic_istream_view : public view_interface<basic_istream_view<_Val, _CharT, _Traits>> {
+ class __iterator;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit basic_istream_view(basic_istream<_CharT, _Traits>& __stream)
+ : __stream_(std::addressof(__stream)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() {
+ *__stream_ >> __value_;
+ return __iterator{*this};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr default_sentinel_t end() const noexcept { return default_sentinel; }
+
+private:
+ basic_istream<_CharT, _Traits>* __stream_;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Val __value_ = _Val();
+};
+
+template <movable _Val, class _CharT, class _Traits>
+ requires default_initializable<_Val> && __stream_extractable<_Val, _CharT, _Traits>
+class basic_istream_view<_Val, _CharT, _Traits>::__iterator {
+public:
+ using iterator_concept = input_iterator_tag;
+ using difference_type = ptrdiff_t;
+ using value_type = _Val;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(basic_istream_view<_Val, _CharT, _Traits>& __parent) noexcept
+ : __parent_(std::addressof(__parent)) {}
+
+ __iterator(const __iterator&) = delete;
+ _LIBCPP_HIDE_FROM_ABI __iterator(__iterator&&) = default;
+
+ __iterator& operator=(const __iterator&) = delete;
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator=(__iterator&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator& operator++() {
+ *__parent_->__stream_ >> __parent_->__value_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void operator++(int) { ++*this; }
+
+ _LIBCPP_HIDE_FROM_ABI _Val& operator*() const { return __parent_->__value_; }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const __iterator& __x, default_sentinel_t) {
+ return !*__x.__get_parent_stream();
+ }
+
+private:
+ basic_istream_view<_Val, _CharT, _Traits>* __parent_;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_istream<_CharT, _Traits>* __get_parent_stream() const {
+ return __parent_->__stream_;
+ }
+};
+
+template <class _Val>
+using istream_view = basic_istream_view<_Val, char>;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _Val>
+using wistream_view = basic_istream_view<_Val, wchar_t>;
+# endif
+
+namespace views {
+namespace __istream {
+
+// clang-format off
+template <class _Tp>
+struct __fn {
+ template <class _Up, class _UnCVRef = remove_cvref_t<_Up>>
+ requires derived_from<_UnCVRef, basic_istream<typename _UnCVRef::char_type,
+ typename _UnCVRef::traits_type>>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Up&& __u) const
+ noexcept(noexcept(basic_istream_view<_Tp, typename _UnCVRef::char_type,
+ typename _UnCVRef::traits_type>(std::forward<_Up>(__u))))
+ -> decltype( basic_istream_view<_Tp, typename _UnCVRef::char_type,
+ typename _UnCVRef::traits_type>(std::forward<_Up>(__u)))
+ { return basic_istream_view<_Tp, typename _UnCVRef::char_type,
+ typename _UnCVRef::traits_type>(std::forward<_Up>(__u));
+ }
+};
+// clang-format on
+
+} // namespace __istream
+
+inline namespace __cpo {
+template <class _Tp>
+inline constexpr auto istream = __istream::__fn<_Tp>{};
+} // namespace __cpo
+} // namespace views
+
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP___RANGES_ISTREAM_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/join_view.h b/libcxx/include/__cxx03/__ranges/join_view.h
new file mode 100644
index 00000000000000..9c2c77995539bd
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/join_view.h
@@ -0,0 +1,423 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_JOIN_VIEW_H
+#define _LIBCPP___RANGES_JOIN_VIEW_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/copyable.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/equality_comparable.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/iterator_with_data.h>
+#include <__iterator/segmented_iterator.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/empty.h>
+#include <__ranges/non_propagating_cache.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/maybe_const.h>
+#include <__utility/as_lvalue.h>
+#include <__utility/empty.h>
+#include <__utility/forward.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <class>
+struct __join_view_iterator_category {};
+
+template <class _View>
+ requires is_reference_v<range_reference_t<_View>> && forward_range<_View> && forward_range<range_reference_t<_View>>
+struct __join_view_iterator_category<_View> {
+ using _OuterC = typename iterator_traits<iterator_t<_View>>::iterator_category;
+ using _InnerC = typename iterator_traits<iterator_t<range_reference_t<_View>>>::iterator_category;
+
+ using iterator_category =
+ _If< derived_from<_OuterC, bidirectional_iterator_tag> && derived_from<_InnerC, bidirectional_iterator_tag> &&
+ common_range<range_reference_t<_View>>,
+ bidirectional_iterator_tag,
+ _If< derived_from<_OuterC, forward_iterator_tag> && derived_from<_InnerC, forward_iterator_tag>,
+ forward_iterator_tag,
+ input_iterator_tag > >;
+};
+
+template <input_range _View>
+ requires view<_View> && input_range<range_reference_t<_View>>
+class join_view : public view_interface<join_view<_View>> {
+private:
+ using _InnerRange = range_reference_t<_View>;
+
+ template <bool>
+ struct __iterator;
+
+ template <bool>
+ struct __sentinel;
+
+ template <class>
+ friend struct std::__segmented_iterator_traits;
+
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+
+ static constexpr bool _UseOuterCache = !forward_range<_View>;
+ using _OuterCache = _If<_UseOuterCache, __non_propagating_cache<iterator_t<_View>>, __empty_cache>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _OuterCache __outer_;
+
+ static constexpr bool _UseInnerCache = !is_reference_v<_InnerRange>;
+ using _InnerCache = _If<_UseInnerCache, __non_propagating_cache<remove_cvref_t<_InnerRange>>, __empty_cache>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _InnerCache __inner_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI join_view()
+ requires default_initializable<_View>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit join_view(_View __base) : __base_(std::move(__base)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() {
+ if constexpr (forward_range<_View>) {
+ constexpr bool __use_const = __simple_view<_View> && is_reference_v<range_reference_t<_View>>;
+ return __iterator<__use_const>{*this, ranges::begin(__base_)};
+ } else {
+ __outer_.__emplace(ranges::begin(__base_));
+ return __iterator<false>{*this};
+ }
+ }
+
+ template <class _V2 = _View>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires forward_range<const _V2> && is_reference_v<range_reference_t<const _V2>> &&
+ input_range<range_reference_t<const _V2>>
+ {
+ return __iterator<true>{*this, ranges::begin(__base_)};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() {
+ if constexpr (forward_range<_View> && is_reference_v<_InnerRange> && forward_range<_InnerRange> &&
+ common_range<_View> && common_range<_InnerRange>)
+ return __iterator<__simple_view<_View>>{*this, ranges::end(__base_)};
+ else
+ return __sentinel<__simple_view<_View>>{*this};
+ }
+
+ template <class _V2 = _View>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires forward_range<const _V2> && is_reference_v<range_reference_t<const _V2>> &&
+ input_range<range_reference_t<const _V2>>
+ {
+ using _ConstInnerRange = range_reference_t<const _View>;
+ if constexpr (forward_range<_ConstInnerRange> && common_range<const _View> && common_range<_ConstInnerRange>) {
+ return __iterator<true>{*this, ranges::end(__base_)};
+ } else {
+ return __sentinel<true>{*this};
+ }
+ }
+};
+
+template <input_range _View>
+ requires view<_View> && input_range<range_reference_t<_View>>
+template <bool _Const>
+struct join_view<_View>::__sentinel {
+private:
+ template <bool>
+ friend struct __sentinel;
+
+ using _Parent = __maybe_const<_Const, join_view>;
+ using _Base = __maybe_const<_Const, _View>;
+ sentinel_t<_Base> __end_ = sentinel_t<_Base>();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(_Parent& __parent) : __end_(ranges::end(__parent.__base_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __s)
+ requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
+ : __end_(std::move(__s.__end_)) {}
+
+ template <bool _OtherConst>
+ requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
+ return __x.__get_outer() == __y.__end_;
+ }
+};
+
+// https://reviews.llvm.org/D142811#inline-1383022
+// To simplify the segmented iterator traits specialization,
+// make the iterator `final`
+template <input_range _View>
+ requires view<_View> && input_range<range_reference_t<_View>>
+template <bool _Const>
+struct join_view<_View>::__iterator final : public __join_view_iterator_category<__maybe_const<_Const, _View>> {
+ friend join_view;
+
+ template <class>
+ friend struct std::__segmented_iterator_traits;
+
+ static constexpr bool __is_join_view_iterator = true;
+
+private:
+ using _Parent = __maybe_const<_Const, join_view<_View>>;
+ using _Base = __maybe_const<_Const, _View>;
+ using _Outer = iterator_t<_Base>;
+ using _Inner = iterator_t<range_reference_t<_Base>>;
+ using _InnerRange = range_reference_t<_View>;
+
+ static_assert(!_Const || forward_range<_Base>, "Const can only be true when Base models forward_range.");
+
+ static constexpr bool __ref_is_glvalue = is_reference_v<range_reference_t<_Base>>;
+
+ static constexpr bool _OuterPresent = forward_range<_Base>;
+ using _OuterType = _If<_OuterPresent, _Outer, std::__empty>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _OuterType __outer_ = _OuterType();
+
+ optional<_Inner> __inner_;
+ _Parent* __parent_ = nullptr;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void __satisfy() {
+ for (; __get_outer() != ranges::end(__parent_->__base_); ++__get_outer()) {
+ auto&& __inner = [this]() -> auto&& {
+ if constexpr (__ref_is_glvalue)
+ return *__get_outer();
+ else
+ return __parent_->__inner_.__emplace_from([&]() -> decltype(auto) { return *__get_outer(); });
+ }();
+ __inner_ = ranges::begin(__inner);
+ if (*__inner_ != ranges::end(__inner))
+ return;
+ }
+
+ if constexpr (__ref_is_glvalue)
+ __inner_.reset();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Outer& __get_outer() {
+ if constexpr (forward_range<_Base>) {
+ return __outer_;
+ } else {
+ return *__parent_->__outer_;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Outer& __get_outer() const {
+ if constexpr (forward_range<_Base>) {
+ return __outer_;
+ } else {
+ return *__parent_->__outer_;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(_Parent& __parent, _Outer __outer)
+ requires forward_range<_Base>
+ : __outer_(std::move(__outer)), __parent_(std::addressof(__parent)) {
+ __satisfy();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(_Parent& __parent)
+ requires(!forward_range<_Base>)
+ : __parent_(std::addressof(__parent)) {
+ __satisfy();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(_Parent* __parent, _Outer __outer, _Inner __inner)
+ requires forward_range<_Base>
+ : __outer_(std::move(__outer)), __inner_(std::move(__inner)), __parent_(__parent) {}
+
+public:
+ using iterator_concept =
+ _If< __ref_is_glvalue && bidirectional_range<_Base> && bidirectional_range<range_reference_t<_Base>> &&
+ common_range<range_reference_t<_Base>>,
+ bidirectional_iterator_tag,
+ _If< __ref_is_glvalue && forward_range<_Base> && forward_range<range_reference_t<_Base>>,
+ forward_iterator_tag,
+ input_iterator_tag > >;
+
+ using value_type = range_value_t<range_reference_t<_Base>>;
+
+ using difference_type = common_type_t< range_difference_t<_Base>, range_difference_t<range_reference_t<_Base>>>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(__iterator<!_Const> __i)
+ requires _Const && convertible_to<iterator_t<_View>, _Outer> && convertible_to<iterator_t<_InnerRange>, _Inner>
+ : __outer_(std::move(__i.__outer_)), __inner_(std::move(__i.__inner_)), __parent_(__i.__parent_) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const { return **__inner_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Inner operator->() const
+ requires __has_arrow<_Inner> && copyable<_Inner>
+ {
+ return *__inner_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ auto __get_inner_range = [&]() -> decltype(auto) {
+ if constexpr (__ref_is_glvalue)
+ return *__get_outer();
+ else
+ return *__parent_->__inner_;
+ };
+ if (++*__inner_ == ranges::end(std::__as_lvalue(__get_inner_range()))) {
+ ++__get_outer();
+ __satisfy();
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator++(int) { ++*this; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int)
+ requires __ref_is_glvalue && forward_range<_Base> && forward_range<range_reference_t<_Base>>
+ {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--()
+ requires __ref_is_glvalue && bidirectional_range<_Base> && bidirectional_range<range_reference_t<_Base>> &&
+ common_range<range_reference_t<_Base>>
+ {
+ if (__outer_ == ranges::end(__parent_->__base_))
+ __inner_ = ranges::end(std::__as_lvalue(*--__outer_));
+
+ // Skip empty inner ranges when going backwards.
+ while (*__inner_ == ranges::begin(std::__as_lvalue(*__outer_))) {
+ __inner_ = ranges::end(std::__as_lvalue(*--__outer_));
+ }
+
+ --*__inner_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int)
+ requires __ref_is_glvalue && bidirectional_range<_Base> && bidirectional_range<range_reference_t<_Base>> &&
+ common_range<range_reference_t<_Base>>
+ {
+ auto __tmp = *this;
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
+ requires __ref_is_glvalue && forward_range<_Base> && equality_comparable<iterator_t<range_reference_t<_Base>>>
+ {
+ return __x.__outer_ == __y.__outer_ && __x.__inner_ == __y.__inner_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr decltype(auto)
+ iter_move(const __iterator& __i) noexcept(noexcept(ranges::iter_move(*__i.__inner_))) {
+ return ranges::iter_move(*__i.__inner_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void
+ iter_swap(const __iterator& __x,
+ const __iterator& __y) noexcept(noexcept(ranges::iter_swap(*__x.__inner_, *__y.__inner_)))
+ requires indirectly_swappable<_Inner>
+ {
+ return ranges::iter_swap(*__x.__inner_, *__y.__inner_);
+ }
+};
+
+template <class _Range>
+explicit join_view(_Range&&) -> join_view<views::all_t<_Range>>;
+
+namespace views {
+namespace __join_view {
+struct __fn : __range_adaptor_closure<__fn> {
+ template <class _Range>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
+ noexcept(noexcept(join_view<all_t<_Range&&>>(std::forward<_Range>(__range))))
+ -> decltype(join_view<all_t<_Range&&>>(std::forward<_Range>(__range))) {
+ return join_view<all_t<_Range&&>>(std::forward<_Range>(__range));
+ }
+};
+} // namespace __join_view
+inline namespace __cpo {
+inline constexpr auto join = __join_view::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+template <class _JoinViewIterator>
+ requires(_JoinViewIterator::__is_join_view_iterator && ranges::common_range<typename _JoinViewIterator::_Parent> &&
+ __has_random_access_iterator_category<typename _JoinViewIterator::_Outer>::value &&
+ __has_random_access_iterator_category<typename _JoinViewIterator::_Inner>::value)
+struct __segmented_iterator_traits<_JoinViewIterator> {
+ using __segment_iterator =
+ _LIBCPP_NODEBUG __iterator_with_data<typename _JoinViewIterator::_Outer, typename _JoinViewIterator::_Parent*>;
+ using __local_iterator = typename _JoinViewIterator::_Inner;
+
+ // TODO: Would it make sense to enable the optimization for other iterator types?
+
+ static constexpr _LIBCPP_HIDE_FROM_ABI __segment_iterator __segment(_JoinViewIterator __iter) {
+ if (ranges::empty(__iter.__parent_->__base_))
+ return {};
+ if (!__iter.__inner_.has_value())
+ return __segment_iterator(--__iter.__outer_, __iter.__parent_);
+ return __segment_iterator(__iter.__outer_, __iter.__parent_);
+ }
+
+ static constexpr _LIBCPP_HIDE_FROM_ABI __local_iterator __local(_JoinViewIterator __iter) {
+ if (ranges::empty(__iter.__parent_->__base_))
+ return {};
+ if (!__iter.__inner_.has_value())
+ return ranges::end(*--__iter.__outer_);
+ return *__iter.__inner_;
+ }
+
+ static constexpr _LIBCPP_HIDE_FROM_ABI __local_iterator __begin(__segment_iterator __iter) {
+ return ranges::begin(*__iter.__get_iter());
+ }
+
+ static constexpr _LIBCPP_HIDE_FROM_ABI __local_iterator __end(__segment_iterator __iter) {
+ return ranges::end(*__iter.__get_iter());
+ }
+
+ static constexpr _LIBCPP_HIDE_FROM_ABI _JoinViewIterator
+ __compose(__segment_iterator __seg_iter, __local_iterator __local_iter) {
+ return _JoinViewIterator(
+ std::move(__seg_iter).__get_data(), std::move(__seg_iter).__get_iter(), std::move(__local_iter));
+ }
+};
+
+#endif // #if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_JOIN_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/lazy_split_view.h b/libcxx/include/__cxx03/__ranges/lazy_split_view.h
new file mode 100644
index 00000000000000..db031fe5f8b49b
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/lazy_split_view.h
@@ -0,0 +1,441 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_LAZY_SPLIT_VIEW_H
+#define _LIBCPP___RANGES_LAZY_SPLIT_VIEW_H
+
+#include <__algorithm/ranges_find.h>
+#include <__algorithm/ranges_mismatch.h>
+#include <__assert>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/derived_from.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/non_propagating_cache.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/single_view.h>
+#include <__ranges/subrange.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/maybe_const.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <auto>
+struct __require_constant;
+
+template <class _Range>
+concept __tiny_range = sized_range<_Range> && requires {
+ typename __require_constant<remove_reference_t<_Range>::size()>;
+} && (remove_reference_t<_Range>::size() <= 1);
+
+template <input_range _View, forward_range _Pattern>
+ requires view<_View> && view<_Pattern> &&
+ indirectly_comparable<iterator_t<_View>, iterator_t<_Pattern>, ranges::equal_to> &&
+ (forward_range<_View> || __tiny_range<_Pattern>)
+class lazy_split_view : public view_interface<lazy_split_view<_View, _Pattern>> {
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+ _LIBCPP_NO_UNIQUE_ADDRESS _Pattern __pattern_ = _Pattern();
+
+ using _MaybeCurrent = _If<!forward_range<_View>, __non_propagating_cache<iterator_t<_View>>, __empty_cache>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _MaybeCurrent __current_ = _MaybeCurrent();
+
+ template <bool>
+ struct __outer_iterator;
+ template <bool>
+ struct __inner_iterator;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI lazy_split_view()
+ requires default_initializable<_View> && default_initializable<_Pattern>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 lazy_split_view(_View __base, _Pattern __pattern)
+ : __base_(std::move(__base)), __pattern_(std::move(__pattern)) {}
+
+ template <input_range _Range>
+ requires constructible_from<_View, views::all_t<_Range>> &&
+ constructible_from<_Pattern, single_view<range_value_t<_Range>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 lazy_split_view(_Range&& __r, range_value_t<_Range> __e)
+ : __base_(views::all(std::forward<_Range>(__r))), __pattern_(views::single(std::move(__e))) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() {
+ if constexpr (forward_range<_View>) {
+ return __outer_iterator < __simple_view<_View> && __simple_view < _Pattern >> {*this, ranges::begin(__base_)};
+ } else {
+ __current_.__emplace(ranges::begin(__base_));
+ return __outer_iterator<false>{*this};
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires forward_range<_View> && forward_range<const _View>
+ {
+ return __outer_iterator<true>{*this, ranges::begin(__base_)};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end()
+ requires forward_range<_View> && common_range<_View>
+ {
+ return __outer_iterator < __simple_view<_View> && __simple_view < _Pattern >> {*this, ranges::end(__base_)};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const {
+ if constexpr (forward_range<_View> && forward_range<const _View> && common_range<const _View>) {
+ return __outer_iterator<true>{*this, ranges::end(__base_)};
+ } else {
+ return default_sentinel;
+ }
+ }
+
+private:
+ template <class>
+ struct __outer_iterator_category {};
+
+ template <forward_range _Tp>
+ struct __outer_iterator_category<_Tp> {
+ using iterator_category = input_iterator_tag;
+ };
+
+ template <bool _Const>
+ struct __outer_iterator : __outer_iterator_category<__maybe_const<_Const, _View>> {
+ private:
+ template <bool>
+ friend struct __inner_iterator;
+ friend __outer_iterator<true>;
+
+ using _Parent = __maybe_const<_Const, lazy_split_view>;
+ using _Base = __maybe_const<_Const, _View>;
+
+ _Parent* __parent_ = nullptr;
+ using _MaybeCurrent = _If<forward_range<_View>, iterator_t<_Base>, __empty_cache>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _MaybeCurrent __current_ = _MaybeCurrent();
+ bool __trailing_empty_ = false;
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto& __current() noexcept {
+ if constexpr (forward_range<_View>) {
+ return __current_;
+ } else {
+ return *__parent_->__current_;
+ }
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr const auto& __current() const noexcept {
+ if constexpr (forward_range<_View>) {
+ return __current_;
+ } else {
+ return *__parent_->__current_;
+ }
+ }
+
+ // Workaround for the GCC issue that doesn't allow calling `__parent_->__base_` from friend functions (because
+ // `__base_` is private).
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto& __parent_base() const noexcept { return __parent_->__base_; }
+
+ public:
+ // using iterator_category = inherited;
+ using iterator_concept = conditional_t<forward_range<_Base>, forward_iterator_tag, input_iterator_tag>;
+ using difference_type = range_difference_t<_Base>;
+
+ struct value_type : view_interface<value_type> {
+ private:
+ __outer_iterator __i_ = __outer_iterator();
+
+ public:
+ _LIBCPP_HIDE_FROM_ABI value_type() = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit value_type(__outer_iterator __i) : __i_(std::move(__i)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __inner_iterator<_Const> begin() const { return __inner_iterator<_Const>{__i_}; }
+ _LIBCPP_HIDE_FROM_ABI constexpr default_sentinel_t end() const noexcept { return default_sentinel; }
+ };
+
+ _LIBCPP_HIDE_FROM_ABI __outer_iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __outer_iterator(_Parent& __parent)
+ requires(!forward_range<_Base>)
+ : __parent_(std::addressof(__parent)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __outer_iterator(_Parent& __parent, iterator_t<_Base> __current)
+ requires forward_range<_Base>
+ : __parent_(std::addressof(__parent)), __current_(std::move(__current)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __outer_iterator(__outer_iterator<!_Const> __i)
+ requires _Const && convertible_to<iterator_t<_View>, iterator_t<_Base>>
+ : __parent_(__i.__parent_), __current_(std::move(__i.__current_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type operator*() const { return value_type{*this}; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __outer_iterator& operator++() {
+ const auto __end = ranges::end(__parent_->__base_);
+ if (__current() == __end) {
+ __trailing_empty_ = false;
+ return *this;
+ }
+
+ const auto [__pbegin, __pend] = ranges::subrange{__parent_->__pattern_};
+ if (__pbegin == __pend) {
+ // Empty pattern: split on every element in the input range
+ ++__current();
+
+ } else if constexpr (__tiny_range<_Pattern>) {
+ // One-element pattern: we can use `ranges::find`.
+ __current() = ranges::find(std::move(__current()), __end, *__pbegin);
+ if (__current() != __end) {
+ // Make sure we point to after the separator we just found.
+ ++__current();
+ if (__current() == __end)
+ __trailing_empty_ = true;
+ }
+
+ } else {
+ // General case for n-element pattern.
+ do {
+ const auto [__b, __p] = ranges::mismatch(__current(), __end, __pbegin, __pend);
+ if (__p == __pend) {
+ __current() = __b;
+ if (__current() == __end) {
+ __trailing_empty_ = true;
+ }
+ break; // The pattern matched; skip it.
+ }
+ } while (++__current() != __end);
+ }
+
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator++(int) {
+ if constexpr (forward_range<_Base>) {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+
+ } else {
+ ++*this;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __outer_iterator& __x, const __outer_iterator& __y)
+ requires forward_range<_Base>
+ {
+ return __x.__current_ == __y.__current_ && __x.__trailing_empty_ == __y.__trailing_empty_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __outer_iterator& __x, default_sentinel_t) {
+ _LIBCPP_ASSERT_NON_NULL(__x.__parent_ != nullptr, "Cannot call comparison on a default-constructed iterator.");
+ return __x.__current() == ranges::end(__x.__parent_base()) && !__x.__trailing_empty_;
+ }
+ };
+
+ template <class>
+ struct __inner_iterator_category {};
+
+ template <forward_range _Tp>
+ struct __inner_iterator_category<_Tp> {
+ using iterator_category =
+ _If< derived_from<typename iterator_traits<iterator_t<_Tp>>::iterator_category, forward_iterator_tag>,
+ forward_iterator_tag,
+ typename iterator_traits<iterator_t<_Tp>>::iterator_category >;
+ };
+
+ template <bool _Const>
+ struct __inner_iterator : __inner_iterator_category<__maybe_const<_Const, _View>> {
+ private:
+ using _Base = __maybe_const<_Const, _View>;
+ // Workaround for a GCC issue.
+ static constexpr bool _OuterConst = _Const;
+ __outer_iterator<_Const> __i_ = __outer_iterator<_OuterConst>();
+ bool __incremented_ = false;
+
+ // Note: these private functions are necessary because GCC doesn't allow calls to private members of `__i_` from
+ // free functions that are friends of `inner-iterator`.
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __is_done() const {
+ _LIBCPP_ASSERT_NON_NULL(__i_.__parent_ != nullptr, "Cannot call comparison on a default-constructed iterator.");
+
+ auto [__pcur, __pend] = ranges::subrange{__i_.__parent_->__pattern_};
+ auto __end = ranges::end(__i_.__parent_->__base_);
+
+ if constexpr (__tiny_range<_Pattern>) {
+ const auto& __cur = __i_.__current();
+ if (__cur == __end)
+ return true;
+ if (__pcur == __pend)
+ return __incremented_;
+
+ return *__cur == *__pcur;
+
+ } else {
+ auto __cur = __i_.__current();
+ if (__cur == __end)
+ return true;
+ if (__pcur == __pend)
+ return __incremented_;
+
+ do {
+ if (*__cur != *__pcur)
+ return false;
+ if (++__pcur == __pend)
+ return true;
+ } while (++__cur != __end);
+
+ return false;
+ }
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto& __outer_current() noexcept { return __i_.__current(); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr const auto& __outer_current() const noexcept {
+ return __i_.__current();
+ }
+
+ public:
+ // using iterator_category = inherited;
+ using iterator_concept = typename __outer_iterator<_Const>::iterator_concept;
+ using value_type = range_value_t<_Base>;
+ using difference_type = range_difference_t<_Base>;
+
+ _LIBCPP_HIDE_FROM_ABI __inner_iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __inner_iterator(__outer_iterator<_Const> __i) : __i_(std::move(__i)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const iterator_t<_Base>& base() const& noexcept { return __i_.__current(); }
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_Base> base() &&
+ requires forward_range<_View>
+ {
+ return std::move(__i_.__current());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const { return *__i_.__current(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __inner_iterator& operator++() {
+ __incremented_ = true;
+
+ if constexpr (!forward_range<_Base>) {
+ if constexpr (_Pattern::size() == 0) {
+ return *this;
+ }
+ }
+
+ ++__i_.__current();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator++(int) {
+ if constexpr (forward_range<_Base>) {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+
+ } else {
+ ++*this;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __inner_iterator& __x, const __inner_iterator& __y)
+ requires forward_range<_Base>
+ {
+ return __x.__outer_current() == __y.__outer_current();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __inner_iterator& __x, default_sentinel_t) {
+ return __x.__is_done();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr decltype(auto)
+ iter_move(const __inner_iterator& __i) noexcept(noexcept(ranges::iter_move(__i.__outer_current()))) {
+ return ranges::iter_move(__i.__outer_current());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void iter_swap(
+ const __inner_iterator& __x,
+ const __inner_iterator& __y) noexcept(noexcept(ranges::iter_swap(__x.__outer_current(), __y.__outer_current())))
+ requires indirectly_swappable<iterator_t<_Base>>
+ {
+ ranges::iter_swap(__x.__outer_current(), __y.__outer_current());
+ }
+ };
+};
+
+template <class _Range, class _Pattern>
+lazy_split_view(_Range&&, _Pattern&&) -> lazy_split_view<views::all_t<_Range>, views::all_t<_Pattern>>;
+
+template <input_range _Range>
+lazy_split_view(_Range&&,
+ range_value_t<_Range>) -> lazy_split_view<views::all_t<_Range>, single_view<range_value_t<_Range>>>;
+
+namespace views {
+namespace __lazy_split_view {
+struct __fn {
+ template <class _Range, class _Pattern>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Pattern&& __pattern) const
+ noexcept(noexcept(lazy_split_view(std::forward<_Range>(__range), std::forward<_Pattern>(__pattern))))
+ -> decltype(lazy_split_view(std::forward<_Range>(__range), std::forward<_Pattern>(__pattern))) {
+ return lazy_split_view(std::forward<_Range>(__range), std::forward<_Pattern>(__pattern));
+ }
+
+ template <class _Pattern>
+ requires constructible_from<decay_t<_Pattern>, _Pattern>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Pattern&& __pattern) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Pattern>, _Pattern>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Pattern>(__pattern)));
+ }
+};
+} // namespace __lazy_split_view
+
+inline namespace __cpo {
+inline constexpr auto lazy_split = __lazy_split_view::__fn{};
+} // namespace __cpo
+} // namespace views
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_LAZY_SPLIT_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/movable_box.h b/libcxx/include/__cxx03/__ranges/movable_box.h
new file mode 100644
index 00000000000000..5a456cc3a1b664
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/movable_box.h
@@ -0,0 +1,247 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_MOVABLE_BOX_H
+#define _LIBCPP___RANGES_MOVABLE_BOX_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/copyable.h>
+#include <__concepts/movable.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory/construct_at.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__utility/move.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// __movable_box allows turning a type that is move-constructible (but maybe not move-assignable) into
+// a type that is both move-constructible and move-assignable. It does that by introducing an empty state
+// and basically doing destroy-then-copy-construct in the assignment operator. The empty state is necessary
+// to handle the case where the copy construction fails after destroying the object.
+//
+// In some cases, we can completely avoid the use of an empty state; we provide a specialization of
+// __movable_box that does this, see below for the details.
+
+// until C++23, `__movable_box` was named `__copyable_box` and required the stored type to be copy-constructible, not
+// just move-constructible; we preserve the old behavior in pre-C++23 modes.
+template <class _Tp>
+concept __movable_box_object =
+# if _LIBCPP_STD_VER >= 23
+ move_constructible<_Tp>
+# else
+ copy_constructible<_Tp>
+# endif
+ && is_object_v<_Tp>;
+
+namespace ranges {
+// Primary template - uses std::optional and introduces an empty state in case assignment fails.
+template <__movable_box_object _Tp>
+class __movable_box {
+ _LIBCPP_NO_UNIQUE_ADDRESS optional<_Tp> __val_;
+
+public:
+ template <class... _Args>
+ requires is_constructible_v<_Tp, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __movable_box(in_place_t, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Tp, _Args...>)
+ : __val_(in_place, std::forward<_Args>(__args)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __movable_box() noexcept(is_nothrow_default_constructible_v<_Tp>)
+ requires default_initializable<_Tp>
+ : __val_(in_place) {}
+
+ _LIBCPP_HIDE_FROM_ABI __movable_box(__movable_box const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __movable_box(__movable_box&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __movable_box&
+ operator=(__movable_box const& __other) noexcept(is_nothrow_copy_constructible_v<_Tp>)
+# if _LIBCPP_STD_VER >= 23
+ requires copy_constructible<_Tp>
+# endif
+ {
+ if (this != std::addressof(__other)) {
+ if (__other.__has_value())
+ __val_.emplace(*__other);
+ else
+ __val_.reset();
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __movable_box& operator=(__movable_box&&)
+ requires movable<_Tp>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __movable_box&
+ operator=(__movable_box&& __other) noexcept(is_nothrow_move_constructible_v<_Tp>) {
+ if (this != std::addressof(__other)) {
+ if (__other.__has_value())
+ __val_.emplace(std::move(*__other));
+ else
+ __val_.reset();
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp const& operator*() const noexcept { return *__val_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& operator*() noexcept { return *__val_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp* operator->() const noexcept { return __val_.operator->(); }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* operator->() noexcept { return __val_.operator->(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __has_value() const noexcept { return __val_.has_value(); }
+};
+
+// This partial specialization implements an optimization for when we know we don't need to store
+// an empty state to represent failure to perform an assignment. For copy-assignment, this happens:
+//
+// 1. If the type is copyable (which includes copy-assignment), we can use the type's own assignment operator
+// directly and avoid using std::optional.
+// 2. If the type is not copyable, but it is nothrow-copy-constructible, then we can implement assignment as
+// destroy-and-then-construct and we know it will never fail, so we don't need an empty state.
+//
+// The exact same reasoning can be applied for move-assignment, with copyable replaced by movable and
+// nothrow-copy-constructible replaced by nothrow-move-constructible. This specialization is enabled
+// whenever we can apply any of these optimizations for both the copy assignment and the move assignment
+// operator.
+
+# if _LIBCPP_STD_VER >= 23
+template <class _Tp>
+concept __doesnt_need_empty_state =
+ (copy_constructible<_Tp>
+ // 1. If copy_constructible<T> is true, movable-box<T> should store only a T if either T models
+ // copyable, or is_nothrow_move_constructible_v<T> && is_nothrow_copy_constructible_v<T> is true.
+ ? copyable<_Tp> || (is_nothrow_move_constructible_v<_Tp> && is_nothrow_copy_constructible_v<_Tp>)
+ // 2. Otherwise, movable-box<T> should store only a T if either T models movable or
+ // is_nothrow_move_constructible_v<T> is true.
+ : movable<_Tp> || is_nothrow_move_constructible_v<_Tp>);
+
+// When _Tp doesn't have an assignment operator, we must implement __movable_box's assignment operator
+// by doing destroy_at followed by construct_at. However, that implementation strategy leads to UB if the nested
+// _Tp is potentially overlapping, as it is doing a non-transparent replacement of the sub-object, which means that
+// we're not considered "nested" inside the movable-box anymore, and since we're not nested within it, [basic.life]/1.5
+// says that we essentially just reused the storage of the movable-box for a completely unrelated object and ended the
+// movable-box's lifetime.
+// https://github.com/llvm/llvm-project/issues/70494#issuecomment-1845646490
+//
+// Hence, when the _Tp doesn't have an assignment operator, we can't risk making it a potentially-overlapping
+// subobject because of the above, and we don't use [[no_unique_address]] in that case.
+template <class _Tp>
+concept __can_use_no_unique_address = (copy_constructible<_Tp> ? copyable<_Tp> : movable<_Tp>);
+
+# else
+
+template <class _Tp>
+concept __doesnt_need_empty_state_for_copy = copyable<_Tp> || is_nothrow_copy_constructible_v<_Tp>;
+
+template <class _Tp>
+concept __doesnt_need_empty_state_for_move = movable<_Tp> || is_nothrow_move_constructible_v<_Tp>;
+
+template <class _Tp>
+concept __doesnt_need_empty_state = __doesnt_need_empty_state_for_copy<_Tp> && __doesnt_need_empty_state_for_move<_Tp>;
+
+template <class _Tp>
+concept __can_use_no_unique_address = copyable<_Tp>;
+# endif
+
+template <class _Tp>
+struct __movable_box_holder {
+ _Tp __val_;
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __movable_box_holder(in_place_t, _Args&&... __args)
+ : __val_(std::forward<_Args>(__args)...) {}
+};
+
+template <class _Tp>
+ requires __can_use_no_unique_address<_Tp>
+struct __movable_box_holder<_Tp> {
+ _LIBCPP_NO_UNIQUE_ADDRESS _Tp __val_;
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __movable_box_holder(in_place_t, _Args&&... __args)
+ : __val_(std::forward<_Args>(__args)...) {}
+};
+
+template <__movable_box_object _Tp>
+ requires __doesnt_need_empty_state<_Tp>
+class __movable_box<_Tp> {
+ _LIBCPP_NO_UNIQUE_ADDRESS __movable_box_holder<_Tp> __holder_;
+
+public:
+ template <class... _Args>
+ requires is_constructible_v<_Tp, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __movable_box(in_place_t __inplace, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Tp, _Args...>)
+ : __holder_(__inplace, std::forward<_Args>(__args)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __movable_box() noexcept(is_nothrow_default_constructible_v<_Tp>)
+ requires default_initializable<_Tp>
+ : __holder_(in_place_t{}) {}
+
+ _LIBCPP_HIDE_FROM_ABI __movable_box(__movable_box const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __movable_box(__movable_box&&) = default;
+
+ // Implementation of assignment operators in case we perform optimization (1)
+ _LIBCPP_HIDE_FROM_ABI __movable_box& operator=(__movable_box const&)
+ requires copyable<_Tp>
+ = default;
+ _LIBCPP_HIDE_FROM_ABI __movable_box& operator=(__movable_box&&)
+ requires movable<_Tp>
+ = default;
+
+ // Implementation of assignment operators in case we perform optimization (2)
+ _LIBCPP_HIDE_FROM_ABI constexpr __movable_box& operator=(__movable_box const& __other) noexcept {
+ static_assert(is_nothrow_copy_constructible_v<_Tp>);
+ static_assert(!__can_use_no_unique_address<_Tp>);
+ if (this != std::addressof(__other)) {
+ std::destroy_at(std::addressof(__holder_.__val_));
+ std::construct_at(std::addressof(__holder_.__val_), __other.__holder_.__val_);
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __movable_box& operator=(__movable_box&& __other) noexcept {
+ static_assert(is_nothrow_move_constructible_v<_Tp>);
+ static_assert(!__can_use_no_unique_address<_Tp>);
+ if (this != std::addressof(__other)) {
+ std::destroy_at(std::addressof(__holder_.__val_));
+ std::construct_at(std::addressof(__holder_.__val_), std::move(__other.__holder_.__val_));
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp const& operator*() const noexcept { return __holder_.__val_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& operator*() noexcept { return __holder_.__val_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp* operator->() const noexcept { return std::addressof(__holder_.__val_); }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* operator->() noexcept { return std::addressof(__holder_.__val_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __has_value() const noexcept { return true; }
+};
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_MOVABLE_BOX_H
diff --git a/libcxx/include/__cxx03/__ranges/non_propagating_cache.h b/libcxx/include/__cxx03/__ranges/non_propagating_cache.h
new file mode 100644
index 00000000000000..b2de2d2ae1cb5b
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/non_propagating_cache.h
@@ -0,0 +1,103 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_NON_PROPAGATING_CACHE_H
+#define _LIBCPP___RANGES_NON_PROPAGATING_CACHE_H
+
+#include <__config>
+#include <__iterator/concepts.h> // indirectly_readable
+#include <__iterator/iterator_traits.h> // iter_reference_t
+#include <__memory/addressof.h>
+#include <__utility/forward.h>
+#include <optional>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+// __non_propagating_cache is a helper type that allows storing an optional value in it,
+// but which does not copy the source's value when it is copy constructed/assigned to,
+// and which resets the source's value when it is moved-from.
+//
+// This type is used as an implementation detail of some views that need to cache the
+// result of `begin()` in order to provide an amortized O(1) begin() method. Typically,
+// we don't want to propagate the value of the cache upon copy because the cached iterator
+// may refer to internal details of the source view.
+template <class _Tp>
+ requires is_object_v<_Tp>
+class _LIBCPP_TEMPLATE_VIS __non_propagating_cache {
+ struct __from_tag {};
+ struct __forward_tag {};
+
+ // This helper class is needed to perform copy and move elision when
+ // constructing the contained type from an iterator.
+ struct __wrapper {
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __wrapper(__forward_tag, _Args&&... __args)
+ : __t_(std::forward<_Args>(__args)...) {}
+ template <class _Fn>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __wrapper(__from_tag, _Fn const& __f) : __t_(__f()) {}
+ _Tp __t_;
+ };
+
+ optional<__wrapper> __value_ = nullopt;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __non_propagating_cache() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __non_propagating_cache(__non_propagating_cache const&) noexcept
+ : __value_(nullopt) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __non_propagating_cache(__non_propagating_cache&& __other) noexcept
+ : __value_(nullopt) {
+ __other.__value_.reset();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __non_propagating_cache& operator=(__non_propagating_cache const& __other) noexcept {
+ if (this != std::addressof(__other)) {
+ __value_.reset();
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __non_propagating_cache& operator=(__non_propagating_cache&& __other) noexcept {
+ __value_.reset();
+ __other.__value_.reset();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& operator*() { return __value_->__t_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp const& operator*() const { return __value_->__t_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool __has_value() const { return __value_.has_value(); }
+
+ template <class _Fn>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& __emplace_from(_Fn const& __f) {
+ return __value_.emplace(__from_tag{}, __f).__t_;
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp& __emplace(_Args&&... __args) {
+ return __value_.emplace(__forward_tag{}, std::forward<_Args>(__args)...).__t_;
+ }
+};
+
+struct __empty_cache {};
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_NON_PROPAGATING_CACHE_H
diff --git a/libcxx/include/__cxx03/__ranges/owning_view.h b/libcxx/include/__cxx03/__ranges/owning_view.h
new file mode 100644
index 00000000000000..254bdb43291190
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/owning_view.h
@@ -0,0 +1,116 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_OWNING_VIEW_H
+#define _LIBCPP___RANGES_OWNING_VIEW_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/movable.h>
+#include <__config>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/data.h>
+#include <__ranges/empty.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/size.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <range _Rp>
+ requires movable<_Rp> && (!__is_std_initializer_list<remove_cvref_t<_Rp>>)
+class owning_view : public view_interface<owning_view<_Rp>> {
+ _Rp __r_ = _Rp();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI owning_view()
+ requires default_initializable<_Rp>
+ = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr owning_view(_Rp&& __r) : __r_(std::move(__r)) {}
+
+ _LIBCPP_HIDE_FROM_ABI owning_view(owning_view&&) = default;
+ _LIBCPP_HIDE_FROM_ABI owning_view& operator=(owning_view&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Rp& base() & noexcept { return __r_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Rp& base() const& noexcept { return __r_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr _Rp&& base() && noexcept { return std::move(__r_); }
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Rp&& base() const&& noexcept { return std::move(__r_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_Rp> begin() { return ranges::begin(__r_); }
+ _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Rp> end() { return ranges::end(__r_); }
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires range<const _Rp>
+ {
+ return ranges::begin(__r_);
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires range<const _Rp>
+ {
+ return ranges::end(__r_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool empty()
+ requires requires { ranges::empty(__r_); }
+ {
+ return ranges::empty(__r_);
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const
+ requires requires { ranges::empty(__r_); }
+ {
+ return ranges::empty(__r_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires sized_range<_Rp>
+ {
+ return ranges::size(__r_);
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<const _Rp>
+ {
+ return ranges::size(__r_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto data()
+ requires contiguous_range<_Rp>
+ {
+ return ranges::data(__r_);
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr auto data() const
+ requires contiguous_range<const _Rp>
+ {
+ return ranges::data(__r_);
+ }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(owning_view);
+
+template <class _Tp>
+inline constexpr bool enable_borrowed_range<owning_view<_Tp>> = enable_borrowed_range<_Tp>;
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_OWNING_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/range_adaptor.h b/libcxx/include/__cxx03/__ranges/range_adaptor.h
new file mode 100644
index 00000000000000..2da246f24e1d2f
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/range_adaptor.h
@@ -0,0 +1,101 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_RANGE_ADAPTOR_H
+#define _LIBCPP___RANGES_RANGE_ADAPTOR_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/invocable.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/compose.h>
+#include <__functional/invoke.h>
+#include <__ranges/concepts.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_class.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+// CRTP base that one can derive from in order to be considered a range adaptor closure
+// by the library. When deriving from this class, a pipe operator will be provided to
+// make the following hold:
+// - `x | f` is equivalent to `f(x)`
+// - `f1 | f2` is an adaptor closure `g` such that `g(x)` is equivalent to `f2(f1(x))`
+template <class _Tp>
+ requires is_class_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>>
+struct __range_adaptor_closure;
+
+// Type that wraps an arbitrary function object and makes it into a range adaptor closure,
+// i.e. something that can be called via the `x | f` notation.
+template <class _Fn>
+struct __range_adaptor_closure_t : _Fn, __range_adaptor_closure<__range_adaptor_closure_t<_Fn>> {
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __range_adaptor_closure_t(_Fn&& __f) : _Fn(std::move(__f)) {}
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(__range_adaptor_closure_t);
+
+template <class _Tp>
+_Tp __derived_from_range_adaptor_closure(__range_adaptor_closure<_Tp>*);
+
+template <class _Tp>
+concept _RangeAdaptorClosure = !ranges::range<remove_cvref_t<_Tp>> && requires {
+ // Ensure that `remove_cvref_t<_Tp>` is derived from `__range_adaptor_closure<remove_cvref_t<_Tp>>` and isn't derived
+ // from `__range_adaptor_closure<U>` for any other type `U`.
+ { ranges::__derived_from_range_adaptor_closure((remove_cvref_t<_Tp>*)nullptr) } -> same_as<remove_cvref_t<_Tp>>;
+};
+
+template <ranges::range _Range, _RangeAdaptorClosure _Closure>
+ requires invocable<_Closure, _Range>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto)
+operator|(_Range&& __range, _Closure&& __closure) noexcept(is_nothrow_invocable_v<_Closure, _Range>) {
+ return std::invoke(std::forward<_Closure>(__closure), std::forward<_Range>(__range));
+}
+
+template <_RangeAdaptorClosure _Closure, _RangeAdaptorClosure _OtherClosure>
+ requires constructible_from<decay_t<_Closure>, _Closure> && constructible_from<decay_t<_OtherClosure>, _OtherClosure>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator|(_Closure&& __c1, _OtherClosure&& __c2) noexcept(
+ is_nothrow_constructible_v<decay_t<_Closure>, _Closure> &&
+ is_nothrow_constructible_v<decay_t<_OtherClosure>, _OtherClosure>) {
+ return __range_adaptor_closure_t(std::__compose(std::forward<_OtherClosure>(__c2), std::forward<_Closure>(__c1)));
+}
+
+template <class _Tp>
+ requires is_class_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>>
+struct __range_adaptor_closure {};
+
+# if _LIBCPP_STD_VER >= 23
+template <class _Tp>
+ requires is_class_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>>
+class range_adaptor_closure : public __range_adaptor_closure<_Tp> {};
+# endif // _LIBCPP_STD_VER >= 23
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_RANGE_ADAPTOR_H
diff --git a/libcxx/include/__cxx03/__ranges/rbegin.h b/libcxx/include/__cxx03/__ranges/rbegin.h
new file mode 100644
index 00000000000000..12e739e1a2b852
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/rbegin.h
@@ -0,0 +1,120 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_RBEGIN_H
+#define _LIBCPP___RANGES_RBEGIN_H
+
+#include <__concepts/class_or_enum.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/readable_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__ranges/access.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/auto_cast.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [ranges.access.rbegin]
+
+namespace ranges {
+namespace __rbegin {
+template <class _Tp>
+concept __member_rbegin = __can_borrow<_Tp> && requires(_Tp&& __t) {
+ { _LIBCPP_AUTO_CAST(__t.rbegin()) } -> input_or_output_iterator;
+};
+
+void rbegin() = delete;
+
+template <class _Tp>
+concept __unqualified_rbegin =
+ !__member_rbegin<_Tp> && __can_borrow<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) {
+ { _LIBCPP_AUTO_CAST(rbegin(__t)) } -> input_or_output_iterator;
+ };
+
+template <class _Tp>
+concept __can_reverse =
+ __can_borrow<_Tp> && !__member_rbegin<_Tp> && !__unqualified_rbegin<_Tp> && requires(_Tp&& __t) {
+ { ranges::begin(__t) } -> same_as<decltype(ranges::end(__t))>;
+ { ranges::begin(__t) } -> bidirectional_iterator;
+ };
+
+struct __fn {
+ template <class _Tp>
+ requires __member_rbegin<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(__t.rbegin()))) {
+ return _LIBCPP_AUTO_CAST(__t.rbegin());
+ }
+
+ template <class _Tp>
+ requires __unqualified_rbegin<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(rbegin(__t)))) {
+ return _LIBCPP_AUTO_CAST(rbegin(__t));
+ }
+
+ template <class _Tp>
+ requires __can_reverse<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept(noexcept(ranges::end(__t))) {
+ return std::make_reverse_iterator(ranges::end(__t));
+ }
+
+ void operator()(auto&&) const = delete;
+};
+} // namespace __rbegin
+
+inline namespace __cpo {
+inline constexpr auto rbegin = __rbegin::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+// [range.access.crbegin]
+
+namespace ranges {
+namespace __crbegin {
+struct __fn {
+ template <class _Tp>
+ requires is_lvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::rbegin(static_cast<const remove_reference_t<_Tp>&>(__t))))
+ -> decltype(ranges::rbegin(static_cast<const remove_reference_t<_Tp>&>(__t))) {
+ return ranges::rbegin(static_cast<const remove_reference_t<_Tp>&>(__t));
+ }
+
+ template <class _Tp>
+ requires is_rvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::rbegin(static_cast<const _Tp&&>(__t))))
+ -> decltype(ranges::rbegin(static_cast<const _Tp&&>(__t))) {
+ return ranges::rbegin(static_cast<const _Tp&&>(__t));
+ }
+};
+} // namespace __crbegin
+
+inline namespace __cpo {
+inline constexpr auto crbegin = __crbegin::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_RBEGIN_H
diff --git a/libcxx/include/__cxx03/__ranges/ref_view.h b/libcxx/include/__cxx03/__ranges/ref_view.h
new file mode 100644
index 00000000000000..5329d778dd30db
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/ref_view.h
@@ -0,0 +1,89 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_REF_VIEW_H
+#define _LIBCPP___RANGES_REF_VIEW_H
+
+#include <__concepts/convertible_to.h>
+#include <__concepts/different_from.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/data.h>
+#include <__ranges/empty.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/size.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/is_object.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <range _Range>
+ requires is_object_v<_Range>
+class ref_view : public view_interface<ref_view<_Range>> {
+ _Range* __range_;
+
+ static void __fun(_Range&);
+ static void __fun(_Range&&) = delete; // NOLINT(modernize-use-equals-delete) ; This is llvm.org/PR54276
+
+public:
+ template <class _Tp>
+ requires __different_from<_Tp, ref_view> && convertible_to<_Tp, _Range&> && requires { __fun(std::declval<_Tp>()); }
+ _LIBCPP_HIDE_FROM_ABI constexpr ref_view(_Tp&& __t)
+ : __range_(std::addressof(static_cast<_Range&>(std::forward<_Tp>(__t)))) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Range& base() const { return *__range_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_Range> begin() const { return ranges::begin(*__range_); }
+ _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Range> end() const { return ranges::end(*__range_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const
+ requires requires { ranges::empty(*__range_); }
+ {
+ return ranges::empty(*__range_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<_Range>
+ {
+ return ranges::size(*__range_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto data() const
+ requires contiguous_range<_Range>
+ {
+ return ranges::data(*__range_);
+ }
+};
+
+template <class _Range>
+ref_view(_Range&) -> ref_view<_Range>;
+
+template <class _Tp>
+inline constexpr bool enable_borrowed_range<ref_view<_Tp>> = true;
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_REF_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/rend.h b/libcxx/include/__cxx03/__ranges/rend.h
new file mode 100644
index 00000000000000..02b4c5999a7ebb
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/rend.h
@@ -0,0 +1,123 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_REND_H
+#define _LIBCPP___RANGES_REND_H
+
+#include <__concepts/class_or_enum.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/readable_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__ranges/access.h>
+#include <__ranges/rbegin.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/auto_cast.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// [range.access.rend]
+
+namespace ranges {
+namespace __rend {
+template <class _Tp>
+concept __member_rend = __can_borrow<_Tp> && requires(_Tp&& __t) {
+ ranges::rbegin(__t);
+ { _LIBCPP_AUTO_CAST(__t.rend()) } -> sentinel_for<decltype(ranges::rbegin(__t))>;
+};
+
+void rend() = delete;
+
+template <class _Tp>
+concept __unqualified_rend =
+ !__member_rend<_Tp> && __can_borrow<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) {
+ ranges::rbegin(__t);
+ { _LIBCPP_AUTO_CAST(rend(__t)) } -> sentinel_for<decltype(ranges::rbegin(__t))>;
+ };
+
+template <class _Tp>
+concept __can_reverse = __can_borrow<_Tp> && !__member_rend<_Tp> && !__unqualified_rend<_Tp> && requires(_Tp&& __t) {
+ { ranges::begin(__t) } -> same_as<decltype(ranges::end(__t))>;
+ { ranges::begin(__t) } -> bidirectional_iterator;
+};
+
+class __fn {
+public:
+ template <class _Tp>
+ requires __member_rend<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(__t.rend()))) {
+ return _LIBCPP_AUTO_CAST(__t.rend());
+ }
+
+ template <class _Tp>
+ requires __unqualified_rend<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(rend(__t)))) {
+ return _LIBCPP_AUTO_CAST(rend(__t));
+ }
+
+ template <class _Tp>
+ requires __can_reverse<_Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::begin(__t))) {
+ return std::make_reverse_iterator(ranges::begin(__t));
+ }
+
+ void operator()(auto&&) const = delete;
+};
+} // namespace __rend
+
+inline namespace __cpo {
+inline constexpr auto rend = __rend::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+// [range.access.crend]
+
+namespace ranges {
+namespace __crend {
+struct __fn {
+ template <class _Tp>
+ requires is_lvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::rend(static_cast<const remove_reference_t<_Tp>&>(__t))))
+ -> decltype(ranges::rend(static_cast<const remove_reference_t<_Tp>&>(__t))) {
+ return ranges::rend(static_cast<const remove_reference_t<_Tp>&>(__t));
+ }
+
+ template <class _Tp>
+ requires is_rvalue_reference_v<_Tp&&>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept(
+ noexcept(ranges::rend(static_cast<const _Tp&&>(__t)))) -> decltype(ranges::rend(static_cast<const _Tp&&>(__t))) {
+ return ranges::rend(static_cast<const _Tp&&>(__t));
+ }
+};
+} // namespace __crend
+
+inline namespace __cpo {
+inline constexpr auto crend = __crend::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_REND_H
diff --git a/libcxx/include/__cxx03/__ranges/repeat_view.h b/libcxx/include/__cxx03/__ranges/repeat_view.h
new file mode 100644
index 00000000000000..53e4beb270ad01
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/repeat_view.h
@@ -0,0 +1,266 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_REPEAT_VIEW_H
+#define _LIBCPP___RANGES_REPEAT_VIEW_H
+
+#include <__assert>
+#include <__concepts/constructible.h>
+#include <__concepts/same_as.h>
+#include <__concepts/semiregular.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/unreachable_sentinel.h>
+#include <__memory/addressof.h>
+#include <__ranges/iota_view.h>
+#include <__ranges/movable_box.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/remove_cv.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+#include <__utility/piecewise_construct.h>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+namespace ranges {
+
+template <class _Tp>
+concept __integer_like_with_usable_difference_type =
+ __signed_integer_like<_Tp> || (__integer_like<_Tp> && weakly_incrementable<_Tp>);
+
+template <class _Tp>
+struct __repeat_view_iterator_difference {
+ using type = _IotaDiffT<_Tp>;
+};
+
+template <__signed_integer_like _Tp>
+struct __repeat_view_iterator_difference<_Tp> {
+ using type = _Tp;
+};
+
+template <class _Tp>
+using __repeat_view_iterator_difference_t = typename __repeat_view_iterator_difference<_Tp>::type;
+
+namespace views::__drop {
+struct __fn;
+} // namespace views::__drop
+
+namespace views::__take {
+struct __fn;
+} // namespace views::__take
+
+template <move_constructible _Tp, semiregular _Bound = unreachable_sentinel_t>
+ requires(is_object_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>> &&
+ (__integer_like_with_usable_difference_type<_Bound> || same_as<_Bound, unreachable_sentinel_t>))
+class _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS repeat_view : public view_interface<repeat_view<_Tp, _Bound>> {
+ friend struct views::__take::__fn;
+ friend struct views::__drop::__fn;
+ class __iterator;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI repeat_view()
+ requires default_initializable<_Tp>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit repeat_view(const _Tp& __value, _Bound __bound_sentinel = _Bound())
+ requires copy_constructible<_Tp>
+ : __value_(in_place, __value), __bound_(__bound_sentinel) {
+ if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
+ _LIBCPP_ASSERT_UNCATEGORIZED(__bound_ >= 0, "The value of bound must be greater than or equal to 0");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit repeat_view(_Tp&& __value, _Bound __bound_sentinel = _Bound())
+ : __value_(in_place, std::move(__value)), __bound_(__bound_sentinel) {
+ if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
+ _LIBCPP_ASSERT_UNCATEGORIZED(__bound_ >= 0, "The value of bound must be greater than or equal to 0");
+ }
+
+ template <class... _TpArgs, class... _BoundArgs>
+ requires(constructible_from<_Tp, _TpArgs...> && constructible_from<_Bound, _BoundArgs...>)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit repeat_view(
+ piecewise_construct_t, tuple<_TpArgs...> __value_args, tuple<_BoundArgs...> __bound_args = tuple<>{})
+ : __value_(in_place, std::make_from_tuple<_Tp>(std::move(__value_args))),
+ __bound_(std::make_from_tuple<_Bound>(std::move(__bound_args))) {
+ if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
+ _LIBCPP_ASSERT_UNCATEGORIZED(
+ __bound_ >= 0, "The behavior is undefined if Bound is not unreachable_sentinel_t and bound is negative");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator begin() const { return __iterator(std::addressof(*__value_)); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator end() const
+ requires(!same_as<_Bound, unreachable_sentinel_t>)
+ {
+ return __iterator(std::addressof(*__value_), __bound_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr unreachable_sentinel_t end() const noexcept { return unreachable_sentinel; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires(!same_as<_Bound, unreachable_sentinel_t>)
+ {
+ return std::__to_unsigned_like(__bound_);
+ }
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS __movable_box<_Tp> __value_;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Bound __bound_ = _Bound();
+};
+
+template <class _Tp, class _Bound = unreachable_sentinel_t>
+repeat_view(_Tp, _Bound = _Bound()) -> repeat_view<_Tp, _Bound>;
+
+// [range.repeat.iterator]
+template <move_constructible _Tp, semiregular _Bound>
+ requires(is_object_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>> &&
+ (__integer_like_with_usable_difference_type<_Bound> || same_as<_Bound, unreachable_sentinel_t>))
+class repeat_view<_Tp, _Bound>::__iterator {
+ friend class repeat_view;
+
+ using _IndexT = conditional_t<same_as<_Bound, unreachable_sentinel_t>, ptrdiff_t, _Bound>;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(const _Tp* __value, _IndexT __bound_sentinel = _IndexT())
+ : __value_(__value), __current_(__bound_sentinel) {}
+
+public:
+ using iterator_concept = random_access_iterator_tag;
+ using iterator_category = random_access_iterator_tag;
+ using value_type = _Tp;
+ using difference_type = __repeat_view_iterator_difference_t<_IndexT>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& operator*() const noexcept { return *__value_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ ++__current_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int) {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--() {
+ if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
+ _LIBCPP_ASSERT_UNCATEGORIZED(__current_ > 0, "The value of bound must be greater than or equal to 0");
+ --__current_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int) {
+ auto __tmp = *this;
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator+=(difference_type __n) {
+ if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
+ _LIBCPP_ASSERT_UNCATEGORIZED(__current_ + __n >= 0, "The value of bound must be greater than or equal to 0");
+ __current_ += __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator-=(difference_type __n) {
+ if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
+ _LIBCPP_ASSERT_UNCATEGORIZED(__current_ - __n >= 0, "The value of bound must be greater than or equal to 0");
+ __current_ -= __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& operator[](difference_type __n) const noexcept { return *(*this + __n); }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y) {
+ return __x.__current_ == __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y) {
+ return __x.__current_ <=> __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(__iterator __i, difference_type __n) {
+ __i += __n;
+ return __i;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(difference_type __n, __iterator __i) {
+ __i += __n;
+ return __i;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator-(__iterator __i, difference_type __n) {
+ __i -= __n;
+ return __i;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y) {
+ return static_cast<difference_type>(__x.__current_) - static_cast<difference_type>(__y.__current_);
+ }
+
+private:
+ const _Tp* __value_ = nullptr;
+ _IndexT __current_ = _IndexT();
+};
+
+// clang-format off
+namespace views {
+namespace __repeat {
+struct __fn {
+ template <class _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Tp&& __value)
+ noexcept(noexcept(ranges::repeat_view<decay_t<_Tp>>(std::forward<_Tp>(__value))))
+ -> decltype( ranges::repeat_view<decay_t<_Tp>>(std::forward<_Tp>(__value)))
+ { return ranges::repeat_view<decay_t<_Tp>>(std::forward<_Tp>(__value)); }
+
+ template <class _Tp, class _Bound>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Tp&& __value, _Bound&& __bound_sentinel)
+ noexcept(noexcept(ranges::repeat_view(std::forward<_Tp>(__value), std::forward<_Bound>(__bound_sentinel))))
+ -> decltype( ranges::repeat_view(std::forward<_Tp>(__value), std::forward<_Bound>(__bound_sentinel)))
+ { return ranges::repeat_view(std::forward<_Tp>(__value), std::forward<_Bound>(__bound_sentinel)); }
+};
+} // namespace __repeat
+// clang-format on
+
+inline namespace __cpo {
+inline constexpr auto repeat = __repeat::__fn{};
+} // namespace __cpo
+} // namespace views
+
+template <class _Tp>
+inline constexpr bool __is_repeat_specialization = false;
+
+template <class _Tp, class _Bound>
+inline constexpr bool __is_repeat_specialization<repeat_view<_Tp, _Bound>> = true;
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_REPEAT_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/reverse_view.h b/libcxx/include/__cxx03/__ranges/reverse_view.h
new file mode 100644
index 00000000000000..796f5be22328b5
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/reverse_view.h
@@ -0,0 +1,203 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_REVERSE_VIEW_H
+#define _LIBCPP___RANGES_REVERSE_VIEW_H
+
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/next.h>
+#include <__iterator/reverse_iterator.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/non_propagating_cache.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/size.h>
+#include <__ranges/subrange.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <view _View>
+ requires bidirectional_range<_View>
+class reverse_view : public view_interface<reverse_view<_View>> {
+ // We cache begin() whenever ranges::next is not guaranteed O(1) to provide an
+ // amortized O(1) begin() method.
+ static constexpr bool _UseCache = !random_access_range<_View> && !common_range<_View>;
+ using _Cache = _If<_UseCache, __non_propagating_cache<reverse_iterator<iterator_t<_View>>>, __empty_cache>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Cache __cached_begin_ = _Cache();
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI reverse_view()
+ requires default_initializable<_View>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit reverse_view(_View __view) : __base_(std::move(__view)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator<iterator_t<_View>> begin() {
+ if constexpr (_UseCache)
+ if (__cached_begin_.__has_value())
+ return *__cached_begin_;
+
+ auto __tmp = std::make_reverse_iterator(ranges::next(ranges::begin(__base_), ranges::end(__base_)));
+ if constexpr (_UseCache)
+ __cached_begin_.__emplace(__tmp);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator<iterator_t<_View>> begin()
+ requires common_range<_View>
+ {
+ return std::make_reverse_iterator(ranges::end(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires common_range<const _View>
+ {
+ return std::make_reverse_iterator(ranges::end(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator<iterator_t<_View>> end() {
+ return std::make_reverse_iterator(ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires common_range<const _View>
+ {
+ return std::make_reverse_iterator(ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires sized_range<_View>
+ {
+ return ranges::size(__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<const _View>
+ {
+ return ranges::size(__base_);
+ }
+};
+
+template <class _Range>
+reverse_view(_Range&&) -> reverse_view<views::all_t<_Range>>;
+
+template <class _Tp>
+inline constexpr bool enable_borrowed_range<reverse_view<_Tp>> = enable_borrowed_range<_Tp>;
+
+namespace views {
+namespace __reverse {
+template <class _Tp>
+inline constexpr bool __is_reverse_view = false;
+
+template <class _Tp>
+inline constexpr bool __is_reverse_view<reverse_view<_Tp>> = true;
+
+template <class _Tp>
+inline constexpr bool __is_sized_reverse_subrange = false;
+
+template <class _Iter>
+inline constexpr bool
+ __is_sized_reverse_subrange<subrange<reverse_iterator<_Iter>, reverse_iterator<_Iter>, subrange_kind::sized>> =
+ true;
+
+template <class _Tp>
+inline constexpr bool __is_unsized_reverse_subrange = false;
+
+template <class _Iter, subrange_kind _Kind>
+inline constexpr bool __is_unsized_reverse_subrange<subrange<reverse_iterator<_Iter>, reverse_iterator<_Iter>, _Kind>> =
+ _Kind == subrange_kind::unsized;
+
+template <class _Tp>
+struct __unwrapped_reverse_subrange {
+ using type =
+ void; // avoid SFINAE-ing out the overload below -- let the concept requirements do it for better diagnostics
+};
+
+template <class _Iter, subrange_kind _Kind>
+struct __unwrapped_reverse_subrange<subrange<reverse_iterator<_Iter>, reverse_iterator<_Iter>, _Kind>> {
+ using type = subrange<_Iter, _Iter, _Kind>;
+};
+
+struct __fn : __range_adaptor_closure<__fn> {
+ template <class _Range>
+ requires __is_reverse_view<remove_cvref_t<_Range>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
+ noexcept(noexcept(std::forward<_Range>(__range).base())) -> decltype(std::forward<_Range>(__range).base()) {
+ return std::forward<_Range>(__range).base();
+ }
+
+ template <class _Range,
+ class _UnwrappedSubrange = typename __unwrapped_reverse_subrange<remove_cvref_t<_Range>>::type>
+ requires __is_sized_reverse_subrange<remove_cvref_t<_Range>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
+ noexcept(noexcept(_UnwrappedSubrange(__range.end().base(), __range.begin().base(), __range.size())))
+ -> decltype(_UnwrappedSubrange(__range.end().base(), __range.begin().base(), __range.size())) {
+ return _UnwrappedSubrange(__range.end().base(), __range.begin().base(), __range.size());
+ }
+
+ template <class _Range,
+ class _UnwrappedSubrange = typename __unwrapped_reverse_subrange<remove_cvref_t<_Range>>::type>
+ requires __is_unsized_reverse_subrange<remove_cvref_t<_Range>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
+ noexcept(noexcept(_UnwrappedSubrange(__range.end().base(), __range.begin().base())))
+ -> decltype(_UnwrappedSubrange(__range.end().base(), __range.begin().base())) {
+ return _UnwrappedSubrange(__range.end().base(), __range.begin().base());
+ }
+
+ template <class _Range>
+ requires(!__is_reverse_view<remove_cvref_t<_Range>> && !__is_sized_reverse_subrange<remove_cvref_t<_Range>> &&
+ !__is_unsized_reverse_subrange<remove_cvref_t<_Range>>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const noexcept(noexcept(reverse_view{
+ std::forward<_Range>(__range)})) -> decltype(reverse_view{std::forward<_Range>(__range)}) {
+ return reverse_view{std::forward<_Range>(__range)};
+ }
+};
+} // namespace __reverse
+
+inline namespace __cpo {
+inline constexpr auto reverse = __reverse::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_REVERSE_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/single_view.h b/libcxx/include/__cxx03/__ranges/single_view.h
new file mode 100644
index 00000000000000..45244f34994d74
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/single_view.h
@@ -0,0 +1,111 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_SINGLE_VIEW_H
+#define _LIBCPP___RANGES_SINGLE_VIEW_H
+
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__ranges/movable_box.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_object.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+# if _LIBCPP_STD_VER >= 23
+template <move_constructible _Tp>
+# else
+template <copy_constructible _Tp>
+# endif
+ requires is_object_v<_Tp>
+class _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS single_view : public view_interface<single_view<_Tp>> {
+ _LIBCPP_NO_UNIQUE_ADDRESS __movable_box<_Tp> __value_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI single_view()
+ requires default_initializable<_Tp>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit single_view(const _Tp& __t)
+# if _LIBCPP_STD_VER >= 23
+ requires copy_constructible<_Tp>
+# endif
+ : __value_(in_place, __t) {
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit single_view(_Tp&& __t) : __value_(in_place, std::move(__t)) {}
+
+ template <class... _Args>
+ requires constructible_from<_Tp, _Args...>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit single_view(in_place_t, _Args&&... __args)
+ : __value_{in_place, std::forward<_Args>(__args)...} {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* begin() noexcept { return data(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp* begin() const noexcept { return data(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* end() noexcept { return data() + 1; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp* end() const noexcept { return data() + 1; }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool empty() noexcept { return false; }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t size() noexcept { return 1; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Tp* data() noexcept { return __value_.operator->(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp* data() const noexcept { return __value_.operator->(); }
+};
+
+template <class _Tp>
+single_view(_Tp) -> single_view<_Tp>;
+
+namespace views {
+namespace __single_view {
+
+struct __fn : __range_adaptor_closure<__fn> {
+ template <class _Range>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
+ noexcept(noexcept(single_view<decay_t<_Range&&>>(std::forward<_Range>(__range))))
+ -> decltype(single_view<decay_t<_Range&&>>(std::forward<_Range>(__range))) {
+ return single_view<decay_t<_Range&&>>(std::forward<_Range>(__range));
+ }
+};
+} // namespace __single_view
+
+inline namespace __cpo {
+inline constexpr auto single = __single_view::__fn{};
+} // namespace __cpo
+
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_SINGLE_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/size.h b/libcxx/include/__cxx03/__ranges/size.h
new file mode 100644
index 00000000000000..40b0c6b6aad7a3
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/size.h
@@ -0,0 +1,137 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_SIZE_H
+#define _LIBCPP___RANGES_SIZE_H
+
+#include <__concepts/arithmetic.h>
+#include <__concepts/class_or_enum.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/make_signed.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/auto_cast.h>
+#include <__utility/declval.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <class>
+inline constexpr bool disable_sized_range = false;
+} // namespace ranges
+
+// [range.prim.size]
+
+namespace ranges {
+namespace __size {
+void size() = delete;
+
+template <class _Tp>
+concept __size_enabled = !disable_sized_range<remove_cvref_t<_Tp>>;
+
+template <class _Tp>
+concept __member_size = __size_enabled<_Tp> && requires(_Tp&& __t) {
+ { _LIBCPP_AUTO_CAST(__t.size()) } -> __integer_like;
+};
+
+template <class _Tp>
+concept __unqualified_size =
+ __size_enabled<_Tp> && !__member_size<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) {
+ { _LIBCPP_AUTO_CAST(size(__t)) } -> __integer_like;
+ };
+
+template <class _Tp>
+concept __difference =
+ !__member_size<_Tp> && !__unqualified_size<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) {
+ { ranges::begin(__t) } -> forward_iterator;
+ { ranges::end(__t) } -> sized_sentinel_for<decltype(ranges::begin(std::declval<_Tp>()))>;
+ };
+
+struct __fn {
+ // `[range.prim.size]`: the array case (for rvalues).
+ template <class _Tp, size_t _Sz>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr size_t operator()(_Tp (&&)[_Sz]) const noexcept {
+ return _Sz;
+ }
+
+ // `[range.prim.size]`: the array case (for lvalues).
+ template <class _Tp, size_t _Sz>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr size_t operator()(_Tp (&)[_Sz]) const noexcept {
+ return _Sz;
+ }
+
+ // `[range.prim.size]`: `auto(t.size())` is a valid expression.
+ template <__member_size _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __integer_like auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(__t.size()))) {
+ return _LIBCPP_AUTO_CAST(__t.size());
+ }
+
+ // `[range.prim.size]`: `auto(size(t))` is a valid expression.
+ template <__unqualified_size _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __integer_like auto operator()(_Tp&& __t) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(size(__t)))) {
+ return _LIBCPP_AUTO_CAST(size(__t));
+ }
+
+ // [range.prim.size]: the `to-unsigned-like` case.
+ template <__difference _Tp>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
+ noexcept(noexcept(std::__to_unsigned_like(ranges::end(__t) - ranges::begin(__t))))
+ -> decltype(std::__to_unsigned_like(ranges::end(__t) - ranges::begin(__t))) {
+ return std::__to_unsigned_like(ranges::end(__t) - ranges::begin(__t));
+ }
+};
+
+} // namespace __size
+
+inline namespace __cpo {
+inline constexpr auto size = __size::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+// [range.prim.ssize]
+
+namespace ranges {
+namespace __ssize {
+struct __fn {
+ template <class _Tp>
+ requires requires(_Tp&& __t) { ranges::size(__t); }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr integral auto operator()(_Tp&& __t) const
+ noexcept(noexcept(ranges::size(__t))) {
+ using _Signed = make_signed_t<decltype(ranges::size(__t))>;
+ if constexpr (sizeof(ptrdiff_t) > sizeof(_Signed))
+ return static_cast<ptrdiff_t>(ranges::size(__t));
+ else
+ return static_cast<_Signed>(ranges::size(__t));
+ }
+};
+} // namespace __ssize
+
+inline namespace __cpo {
+inline constexpr auto ssize = __ssize::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_SIZE_H
diff --git a/libcxx/include/__cxx03/__ranges/split_view.h b/libcxx/include/__cxx03/__ranges/split_view.h
new file mode 100644
index 00000000000000..ce3606aedfefb9
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/split_view.h
@@ -0,0 +1,232 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_SPLIT_VIEW_H
+#define _LIBCPP___RANGES_SPLIT_VIEW_H
+
+#include <__algorithm/ranges_search.h>
+#include <__concepts/constructible.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/indirectly_comparable.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/empty.h>
+#include <__ranges/non_propagating_cache.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/single_view.h>
+#include <__ranges/subrange.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <forward_range _View, forward_range _Pattern>
+ requires view<_View> && view<_Pattern> &&
+ indirectly_comparable<iterator_t<_View>, iterator_t<_Pattern>, ranges::equal_to>
+class split_view : public view_interface<split_view<_View, _Pattern>> {
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+ _LIBCPP_NO_UNIQUE_ADDRESS _Pattern __pattern_ = _Pattern();
+ using _Cache = __non_propagating_cache<subrange<iterator_t<_View>>>;
+ _Cache __cached_begin_ = _Cache();
+
+ template <class, class>
+ friend struct __iterator;
+
+ template <class, class>
+ friend struct __sentinel;
+
+ struct __iterator;
+ struct __sentinel;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange<iterator_t<_View>> __find_next(iterator_t<_View> __it) {
+ auto [__begin, __end] = ranges::search(subrange(__it, ranges::end(__base_)), __pattern_);
+ if (__begin != ranges::end(__base_) && ranges::empty(__pattern_)) {
+ ++__begin;
+ ++__end;
+ }
+ return {__begin, __end};
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI split_view()
+ requires default_initializable<_View> && default_initializable<_Pattern>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 split_view(_View __base, _Pattern __pattern)
+ : __base_(std::move(__base)), __pattern_(std::move((__pattern))) {}
+
+ template <forward_range _Range>
+ requires constructible_from<_View, views::all_t<_Range>> &&
+ constructible_from<_Pattern, single_view<range_value_t<_Range>>>
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23
+ split_view(_Range&& __range, range_value_t<_Range> __elem)
+ : __base_(views::all(std::forward<_Range>(__range))), __pattern_(views::single(std::move(__elem))) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator begin() {
+ if (!__cached_begin_.__has_value()) {
+ __cached_begin_.__emplace(__find_next(ranges::begin(__base_)));
+ }
+ return {*this, ranges::begin(__base_), *__cached_begin_};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() {
+ if constexpr (common_range<_View>) {
+ return __iterator{*this, ranges::end(__base_), {}};
+ } else {
+ return __sentinel{*this};
+ }
+ }
+};
+
+template <class _Range, class _Pattern>
+split_view(_Range&&, _Pattern&&) -> split_view<views::all_t<_Range>, views::all_t<_Pattern>>;
+
+template <forward_range _Range>
+split_view(_Range&&, range_value_t<_Range>) -> split_view<views::all_t<_Range>, single_view<range_value_t<_Range>>>;
+
+template <forward_range _View, forward_range _Pattern>
+ requires view<_View> && view<_Pattern> &&
+ indirectly_comparable<iterator_t<_View>, iterator_t<_Pattern>, ranges::equal_to>
+struct split_view<_View, _Pattern>::__iterator {
+private:
+ split_view* __parent_ = nullptr;
+ _LIBCPP_NO_UNIQUE_ADDRESS iterator_t<_View> __cur_ = iterator_t<_View>();
+ _LIBCPP_NO_UNIQUE_ADDRESS subrange<iterator_t<_View>> __next_ = subrange<iterator_t<_View>>();
+ bool __trailing_empty_ = false;
+
+ friend struct __sentinel;
+
+public:
+ using iterator_concept = forward_iterator_tag;
+ using iterator_category = input_iterator_tag;
+ using value_type = subrange<iterator_t<_View>>;
+ using difference_type = range_difference_t<_View>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(
+ split_view<_View, _Pattern>& __parent, iterator_t<_View> __current, subrange<iterator_t<_View>> __next)
+ : __parent_(std::addressof(__parent)), __cur_(std::move(__current)), __next_(std::move(__next)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_View> base() const { return __cur_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type operator*() const { return {__cur_, __next_.begin()}; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ __cur_ = __next_.begin();
+ if (__cur_ != ranges::end(__parent_->__base_)) {
+ __cur_ = __next_.end();
+ if (__cur_ == ranges::end(__parent_->__base_)) {
+ __trailing_empty_ = true;
+ __next_ = {__cur_, __cur_};
+ } else {
+ __next_ = __parent_->__find_next(__cur_);
+ }
+ } else {
+ __trailing_empty_ = false;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int) {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y) {
+ return __x.__cur_ == __y.__cur_ && __x.__trailing_empty_ == __y.__trailing_empty_;
+ }
+};
+
+template <forward_range _View, forward_range _Pattern>
+ requires view<_View> && view<_Pattern> &&
+ indirectly_comparable<iterator_t<_View>, iterator_t<_Pattern>, ranges::equal_to>
+struct split_view<_View, _Pattern>::__sentinel {
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS sentinel_t<_View> __end_ = sentinel_t<_View>();
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __equals(const __iterator& __x, const __sentinel& __y) {
+ return __x.__cur_ == __y.__end_ && !__x.__trailing_empty_;
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(split_view<_View, _Pattern>& __parent)
+ : __end_(ranges::end(__parent.__base_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __sentinel& __y) {
+ return __equals(__x, __y);
+ }
+};
+
+namespace views {
+namespace __split_view {
+struct __fn {
+ // clang-format off
+ template <class _Range, class _Pattern>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI
+ constexpr auto operator()(_Range&& __range, _Pattern&& __pattern) const
+ noexcept(noexcept(split_view(std::forward<_Range>(__range), std::forward<_Pattern>(__pattern))))
+ -> decltype( split_view(std::forward<_Range>(__range), std::forward<_Pattern>(__pattern)))
+ { return split_view(std::forward<_Range>(__range), std::forward<_Pattern>(__pattern)); }
+ // clang-format on
+
+ template <class _Pattern>
+ requires constructible_from<decay_t<_Pattern>, _Pattern>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Pattern&& __pattern) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Pattern>, _Pattern>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Pattern>(__pattern)));
+ }
+};
+} // namespace __split_view
+
+inline namespace __cpo {
+inline constexpr auto split = __split_view::__fn{};
+} // namespace __cpo
+} // namespace views
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_SPLIT_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/subrange.h b/libcxx/include/__cxx03/__ranges/subrange.h
new file mode 100644
index 00000000000000..aba584ef933542
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/subrange.h
@@ -0,0 +1,273 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_SUBRANGE_H
+#define _LIBCPP___RANGES_SUBRANGE_H
+
+#include <__assert>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/copyable.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/different_from.h>
+#include <__config>
+#include <__fwd/subrange.h>
+#include <__iterator/advance.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/size.h>
+#include <__ranges/view_interface.h>
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_like_no_subrange.h>
+#include <__tuple/tuple_size.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_pointer.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+template <class _From, class _To>
+concept __uses_nonqualification_pointer_conversion =
+ is_pointer_v<_From> && is_pointer_v<_To> &&
+ !convertible_to<remove_pointer_t<_From> (*)[], remove_pointer_t<_To> (*)[]>;
+
+template <class _From, class _To>
+concept __convertible_to_non_slicing =
+ convertible_to<_From, _To> && !__uses_nonqualification_pointer_conversion<decay_t<_From>, decay_t<_To>>;
+
+template <class _Pair, class _Iter, class _Sent>
+concept __pair_like_convertible_from =
+ !range<_Pair> && __pair_like_no_subrange<_Pair> && constructible_from<_Pair, _Iter, _Sent> &&
+ __convertible_to_non_slicing<_Iter, tuple_element_t<0, _Pair>> && convertible_to<_Sent, tuple_element_t<1, _Pair>>;
+
+template <input_or_output_iterator _Iter,
+ sentinel_for<_Iter> _Sent = _Iter,
+ subrange_kind _Kind = sized_sentinel_for<_Sent, _Iter> ? subrange_kind::sized : subrange_kind::unsized>
+ requires(_Kind == subrange_kind::sized || !sized_sentinel_for<_Sent, _Iter>)
+class _LIBCPP_TEMPLATE_VIS subrange : public view_interface<subrange<_Iter, _Sent, _Kind>> {
+public:
+ // Note: this is an internal implementation detail that is public only for internal usage.
+ static constexpr bool _StoreSize = (_Kind == subrange_kind::sized && !sized_sentinel_for<_Sent, _Iter>);
+
+private:
+ static constexpr bool _MustProvideSizeAtConstruction = !_StoreSize; // just to improve compiler diagnostics
+ struct _Empty {
+ _LIBCPP_HIDE_FROM_ABI constexpr _Empty(auto) noexcept {}
+ };
+ using _Size = conditional_t<_StoreSize, make_unsigned_t<iter_difference_t<_Iter>>, _Empty>;
+ _LIBCPP_NO_UNIQUE_ADDRESS _Iter __begin_ = _Iter();
+ _LIBCPP_NO_UNIQUE_ADDRESS _Sent __end_ = _Sent();
+ _LIBCPP_NO_UNIQUE_ADDRESS _Size __size_ = 0;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI subrange()
+ requires default_initializable<_Iter>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange(__convertible_to_non_slicing<_Iter> auto __iter, _Sent __sent)
+ requires _MustProvideSizeAtConstruction
+ : __begin_(std::move(__iter)), __end_(std::move(__sent)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange(
+ __convertible_to_non_slicing<_Iter> auto __iter, _Sent __sent, make_unsigned_t<iter_difference_t<_Iter>> __n)
+ requires(_Kind == subrange_kind::sized)
+ : __begin_(std::move(__iter)), __end_(std::move(__sent)), __size_(__n) {
+ if constexpr (sized_sentinel_for<_Sent, _Iter>)
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS((__end_ - __begin_) == static_cast<iter_difference_t<_Iter>>(__n),
+ "std::ranges::subrange was passed an invalid size hint");
+ }
+
+ template <__different_from<subrange> _Range>
+ requires borrowed_range<_Range> && __convertible_to_non_slicing<iterator_t<_Range>, _Iter> &&
+ convertible_to<sentinel_t<_Range>, _Sent>
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange(_Range&& __range)
+ requires(!_StoreSize)
+ : subrange(ranges::begin(__range), ranges::end(__range)) {}
+
+ template <__different_from<subrange> _Range>
+ requires borrowed_range<_Range> && __convertible_to_non_slicing<iterator_t<_Range>, _Iter> &&
+ convertible_to<sentinel_t<_Range>, _Sent>
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange(_Range&& __range)
+ requires _StoreSize && sized_range<_Range>
+ : subrange(__range, ranges::size(__range)) {}
+
+ template <borrowed_range _Range>
+ requires __convertible_to_non_slicing<iterator_t<_Range>, _Iter> &&
+ convertible_to<sentinel_t<_Range>, _Sent>
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange(_Range&& __range, make_unsigned_t<iter_difference_t<_Iter>> __n)
+ requires(_Kind == subrange_kind::sized)
+ : subrange(ranges::begin(__range), ranges::end(__range), __n) {}
+
+ template <__pair_like_convertible_from<const _Iter&, const _Sent&> _Pair>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator _Pair() const {
+ return _Pair(__begin_, __end_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Iter begin() const
+ requires copyable<_Iter>
+ {
+ return __begin_;
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Iter begin()
+ requires(!copyable<_Iter>)
+ {
+ return std::move(__begin_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Sent end() const { return __end_; }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const { return __begin_ == __end_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr make_unsigned_t<iter_difference_t<_Iter>> size() const
+ requires(_Kind == subrange_kind::sized)
+ {
+ if constexpr (_StoreSize)
+ return __size_;
+ else
+ return std::__to_unsigned_like(__end_ - __begin_);
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange next(iter_difference_t<_Iter> __n = 1) const&
+ requires forward_iterator<_Iter>
+ {
+ auto __tmp = *this;
+ __tmp.advance(__n);
+ return __tmp;
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange next(iter_difference_t<_Iter> __n = 1) && {
+ advance(__n);
+ return std::move(*this);
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange prev(iter_difference_t<_Iter> __n = 1) const
+ requires bidirectional_iterator<_Iter>
+ {
+ auto __tmp = *this;
+ __tmp.advance(-__n);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr subrange& advance(iter_difference_t<_Iter> __n) {
+ if constexpr (bidirectional_iterator<_Iter>) {
+ if (__n < 0) {
+ ranges::advance(__begin_, __n);
+ if constexpr (_StoreSize)
+ __size_ += std::__to_unsigned_like(-__n);
+ return *this;
+ }
+ }
+
+ auto __d = __n - ranges::advance(__begin_, __n, __end_);
+ if constexpr (_StoreSize)
+ __size_ -= std::__to_unsigned_like(__d);
+ return *this;
+ }
+};
+
+template <input_or_output_iterator _Iter, sentinel_for<_Iter> _Sent>
+subrange(_Iter, _Sent) -> subrange<_Iter, _Sent>;
+
+template <input_or_output_iterator _Iter, sentinel_for<_Iter> _Sent>
+subrange(_Iter, _Sent, make_unsigned_t<iter_difference_t<_Iter>>) -> subrange<_Iter, _Sent, subrange_kind::sized>;
+
+template <borrowed_range _Range>
+subrange(_Range&&) -> subrange<iterator_t<_Range>,
+ sentinel_t<_Range>,
+ (sized_range<_Range> || sized_sentinel_for<sentinel_t<_Range>, iterator_t<_Range>>)
+ ? subrange_kind::sized
+ : subrange_kind::unsized>;
+
+template <borrowed_range _Range>
+subrange(_Range&&, make_unsigned_t<range_difference_t<_Range>>)
+ -> subrange<iterator_t<_Range>, sentinel_t<_Range>, subrange_kind::sized>;
+
+template <size_t _Index, class _Iter, class _Sent, subrange_kind _Kind>
+ requires((_Index == 0 && copyable<_Iter>) || _Index == 1)
+_LIBCPP_HIDE_FROM_ABI constexpr auto get(const subrange<_Iter, _Sent, _Kind>& __subrange) {
+ if constexpr (_Index == 0)
+ return __subrange.begin();
+ else
+ return __subrange.end();
+}
+
+template <size_t _Index, class _Iter, class _Sent, subrange_kind _Kind>
+ requires(_Index < 2)
+_LIBCPP_HIDE_FROM_ABI constexpr auto get(subrange<_Iter, _Sent, _Kind>&& __subrange) {
+ if constexpr (_Index == 0)
+ return __subrange.begin();
+ else
+ return __subrange.end();
+}
+
+template <class _Ip, class _Sp, subrange_kind _Kp>
+inline constexpr bool enable_borrowed_range<subrange<_Ip, _Sp, _Kp>> = true;
+
+template <range _Rp>
+using borrowed_subrange_t = _If<borrowed_range<_Rp>, subrange<iterator_t<_Rp>>, dangling>;
+} // namespace ranges
+
+// [range.subrange.general]
+
+using ranges::get;
+
+// [ranges.syn]
+
+template <class _Ip, class _Sp, ranges::subrange_kind _Kp>
+struct tuple_size<ranges::subrange<_Ip, _Sp, _Kp>> : integral_constant<size_t, 2> {};
+
+template <class _Ip, class _Sp, ranges::subrange_kind _Kp>
+struct tuple_element<0, ranges::subrange<_Ip, _Sp, _Kp>> {
+ using type = _Ip;
+};
+
+template <class _Ip, class _Sp, ranges::subrange_kind _Kp>
+struct tuple_element<1, ranges::subrange<_Ip, _Sp, _Kp>> {
+ using type = _Sp;
+};
+
+template <class _Ip, class _Sp, ranges::subrange_kind _Kp>
+struct tuple_element<0, const ranges::subrange<_Ip, _Sp, _Kp>> {
+ using type = _Ip;
+};
+
+template <class _Ip, class _Sp, ranges::subrange_kind _Kp>
+struct tuple_element<1, const ranges::subrange<_Ip, _Sp, _Kp>> {
+ using type = _Sp;
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_SUBRANGE_H
diff --git a/libcxx/include/__cxx03/__ranges/take_view.h b/libcxx/include/__cxx03/__ranges/take_view.h
new file mode 100644
index 00000000000000..27ca8155a69b18
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/take_view.h
@@ -0,0 +1,369 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_TAKE_VIEW_H
+#define _LIBCPP___RANGES_TAKE_VIEW_H
+
+#include <__algorithm/min.h>
+#include <__algorithm/ranges_min.h>
+#include <__assert>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__fwd/span.h>
+#include <__fwd/string_view.h>
+#include <__iterator/concepts.h>
+#include <__iterator/counted_iterator.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/empty_view.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/iota_view.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/repeat_view.h>
+#include <__ranges/size.h>
+#include <__ranges/subrange.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/maybe_const.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/auto_cast.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <view _View>
+class take_view : public view_interface<take_view<_View>> {
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+ range_difference_t<_View> __count_ = 0;
+
+ template <bool>
+ class __sentinel;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI take_view()
+ requires default_initializable<_View>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23
+ take_view(_View __base, range_difference_t<_View> __count)
+ : __base_(std::move(__base)), __count_(__count) {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__count >= 0, "count has to be greater than or equal to zero");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
+ requires(!__simple_view<_View>)
+ {
+ if constexpr (sized_range<_View>) {
+ if constexpr (random_access_range<_View>) {
+ return ranges::begin(__base_);
+ } else {
+ using _DifferenceT = range_difference_t<_View>;
+ auto __size = size();
+ return counted_iterator(ranges::begin(__base_), static_cast<_DifferenceT>(__size));
+ }
+ } else {
+ return counted_iterator(ranges::begin(__base_), __count_);
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires range<const _View>
+ {
+ if constexpr (sized_range<const _View>) {
+ if constexpr (random_access_range<const _View>) {
+ return ranges::begin(__base_);
+ } else {
+ using _DifferenceT = range_difference_t<const _View>;
+ auto __size = size();
+ return counted_iterator(ranges::begin(__base_), static_cast<_DifferenceT>(__size));
+ }
+ } else {
+ return counted_iterator(ranges::begin(__base_), __count_);
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end()
+ requires(!__simple_view<_View>)
+ {
+ if constexpr (sized_range<_View>) {
+ if constexpr (random_access_range<_View>) {
+ return ranges::begin(__base_) + size();
+ } else {
+ return default_sentinel;
+ }
+ } else {
+ return __sentinel<false>{ranges::end(__base_)};
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires range<const _View>
+ {
+ if constexpr (sized_range<const _View>) {
+ if constexpr (random_access_range<const _View>) {
+ return ranges::begin(__base_) + size();
+ } else {
+ return default_sentinel;
+ }
+ } else {
+ return __sentinel<true>{ranges::end(__base_)};
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires sized_range<_View>
+ {
+ auto __n = ranges::size(__base_);
+ return ranges::min(__n, static_cast<decltype(__n)>(__count_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<const _View>
+ {
+ auto __n = ranges::size(__base_);
+ return ranges::min(__n, static_cast<decltype(__n)>(__count_));
+ }
+};
+
+template <view _View>
+template <bool _Const>
+class take_view<_View>::__sentinel {
+ using _Base = __maybe_const<_Const, _View>;
+ template <bool _OtherConst>
+ using _Iter = counted_iterator<iterator_t<__maybe_const<_OtherConst, _View>>>;
+ _LIBCPP_NO_UNIQUE_ADDRESS sentinel_t<_Base> __end_ = sentinel_t<_Base>();
+
+ template <bool>
+ friend class take_view<_View>::__sentinel;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(sentinel_t<_Base> __end) : __end_(std::move(__end)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __s)
+ requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
+ : __end_(std::move(__s.__end_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Base> base() const { return __end_; }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const _Iter<_Const>& __lhs, const __sentinel& __rhs) {
+ return __lhs.count() == 0 || __lhs.base() == __rhs.__end_;
+ }
+
+ template <bool _OtherConst = !_Const>
+ requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const _Iter<_OtherConst>& __lhs, const __sentinel& __rhs) {
+ return __lhs.count() == 0 || __lhs.base() == __rhs.__end_;
+ }
+};
+
+template <class _Range>
+take_view(_Range&&, range_difference_t<_Range>) -> take_view<views::all_t<_Range>>;
+
+template <class _Tp>
+inline constexpr bool enable_borrowed_range<take_view<_Tp>> = enable_borrowed_range<_Tp>;
+
+namespace views {
+namespace __take {
+
+template <class _Tp>
+inline constexpr bool __is_empty_view = false;
+
+template <class _Tp>
+inline constexpr bool __is_empty_view<empty_view<_Tp>> = true;
+
+template <class _Tp>
+inline constexpr bool __is_passthrough_specialization = false;
+
+template <class _Tp, size_t _Extent>
+inline constexpr bool __is_passthrough_specialization<span<_Tp, _Extent>> = true;
+
+template <class _CharT, class _Traits>
+inline constexpr bool __is_passthrough_specialization<basic_string_view<_CharT, _Traits>> = true;
+
+template <class _Iter, class _Sent, subrange_kind _Kind>
+inline constexpr bool __is_passthrough_specialization<subrange<_Iter, _Sent, _Kind>> = true;
+
+template <class _Tp>
+inline constexpr bool __is_iota_specialization = false;
+
+template <class _Np, class _Bound>
+inline constexpr bool __is_iota_specialization<iota_view<_Np, _Bound>> = true;
+
+template <class _Tp>
+struct __passthrough_type;
+
+template <class _Tp, size_t _Extent>
+struct __passthrough_type<span<_Tp, _Extent>> {
+ using type = span<_Tp>;
+};
+
+template <class _CharT, class _Traits>
+struct __passthrough_type<basic_string_view<_CharT, _Traits>> {
+ using type = basic_string_view<_CharT, _Traits>;
+};
+
+template <class _Iter, class _Sent, subrange_kind _Kind>
+ requires requires { typename subrange<_Iter>; }
+struct __passthrough_type<subrange<_Iter, _Sent, _Kind>> {
+ using type = subrange<_Iter>;
+};
+
+template <class _Tp>
+using __passthrough_type_t = typename __passthrough_type<_Tp>::type;
+
+struct __fn {
+ // [range.take.overview]: the `empty_view` case.
+ template <class _Range, convertible_to<range_difference_t<_Range>> _Np>
+ requires __is_empty_view<remove_cvref_t<_Range>>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Np&&) const
+ noexcept(noexcept(_LIBCPP_AUTO_CAST(std::forward<_Range>(__range))))
+ -> decltype(_LIBCPP_AUTO_CAST(std::forward<_Range>(__range))) {
+ return _LIBCPP_AUTO_CAST(std::forward<_Range>(__range));
+ }
+
+ // [range.take.overview]: the `span | basic_string_view | subrange` case.
+ template <class _Range,
+ convertible_to<range_difference_t<_Range>> _Np,
+ class _RawRange = remove_cvref_t<_Range>,
+ class _Dist = range_difference_t<_Range>>
+ requires(!__is_empty_view<_RawRange> && random_access_range<_RawRange> && sized_range<_RawRange> &&
+ __is_passthrough_specialization<_RawRange>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto
+ operator()(_Range&& __rng, _Np&& __n) const noexcept(noexcept(__passthrough_type_t<_RawRange>(
+ ranges::begin(__rng), ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)))))
+ -> decltype(__passthrough_type_t<_RawRange>(
+ // Note: deliberately not forwarding `__rng` to guard against double moves.
+ ranges::begin(__rng),
+ ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)))) {
+ return __passthrough_type_t<_RawRange>(
+ ranges::begin(__rng), ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)));
+ }
+
+ // [range.take.overview]: the `iota_view` case.
+ // clang-format off
+ template <class _Range,
+ convertible_to<range_difference_t<_Range>> _Np,
+ class _RawRange = remove_cvref_t<_Range>,
+ class _Dist = range_difference_t<_Range>>
+ requires (!__is_empty_view<_RawRange> &&
+ random_access_range<_RawRange> &&
+ sized_range<_RawRange> &&
+ __is_iota_specialization<_RawRange>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI
+ constexpr auto operator()(_Range&& __rng, _Np&& __n) const
+ noexcept(noexcept(ranges::iota_view(
+ *ranges::begin(__rng),
+ *(ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)))
+ )))
+ -> decltype( ranges::iota_view(
+ // Note: deliberately not forwarding `__rng` to guard against double moves.
+ *ranges::begin(__rng),
+ *(ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)))
+ ))
+ { return ranges::iota_view(
+ *ranges::begin(__rng),
+ *(ranges::begin(__rng) + std::min<_Dist>(ranges::distance(__rng), std::forward<_Np>(__n)))
+ ); }
+
+#if _LIBCPP_STD_VER >= 23
+ // [range.take.overview]: the `repeat_view` "_RawRange models sized_range" case.
+ template <class _Range,
+ convertible_to<range_difference_t<_Range>> _Np,
+ class _RawRange = remove_cvref_t<_Range>,
+ class _Dist = range_difference_t<_Range>>
+ requires(__is_repeat_specialization<_RawRange> && sized_range<_RawRange>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Np&& __n) const
+ noexcept(noexcept(views::repeat(*__range.__value_, std::min<_Dist>(ranges::distance(__range), std::forward<_Np>(__n)))))
+ -> decltype( views::repeat(*__range.__value_, std::min<_Dist>(ranges::distance(__range), std::forward<_Np>(__n))))
+ { return views::repeat(*__range.__value_, std::min<_Dist>(ranges::distance(__range), std::forward<_Np>(__n))); }
+
+ // [range.take.overview]: the `repeat_view` "otherwise" case.
+ template <class _Range,
+ convertible_to<range_difference_t<_Range>> _Np,
+ class _RawRange = remove_cvref_t<_Range>,
+ class _Dist = range_difference_t<_Range>>
+ requires(__is_repeat_specialization<_RawRange> && !sized_range<_RawRange>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Np&& __n) const
+ noexcept(noexcept(views::repeat(*__range.__value_, static_cast<_Dist>(__n))))
+ -> decltype( views::repeat(*__range.__value_, static_cast<_Dist>(__n)))
+ { return views::repeat(*__range.__value_, static_cast<_Dist>(__n)); }
+#endif
+ // clang-format on
+
+ // [range.take.overview]: the "otherwise" case.
+ template <class _Range, convertible_to<range_difference_t<_Range>> _Np, class _RawRange = remove_cvref_t<_Range>>
+ // Note: without specifically excluding the other cases, GCC sees this overload as ambiguous with the other
+ // overloads.
+ requires(!(__is_empty_view<_RawRange> ||
+# if _LIBCPP_STD_VER >= 23
+ __is_repeat_specialization<_RawRange> ||
+# endif
+ (__is_iota_specialization<_RawRange> && sized_range<_RawRange> && random_access_range<_RawRange>) ||
+ (__is_passthrough_specialization<_RawRange> && sized_range<_RawRange> &&
+ random_access_range<_RawRange>)))
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Np&& __n) const
+ noexcept(noexcept(take_view(std::forward<_Range>(__range), std::forward<_Np>(__n))))
+ -> decltype(take_view(std::forward<_Range>(__range), std::forward<_Np>(__n))) {
+ return take_view(std::forward<_Range>(__range), std::forward<_Np>(__n));
+ }
+
+ template <class _Np>
+ requires constructible_from<decay_t<_Np>, _Np>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Np&& __n) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Np>, _Np>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Np>(__n)));
+ }
+};
+
+} // namespace __take
+
+inline namespace __cpo {
+inline constexpr auto take = __take::__fn{};
+} // namespace __cpo
+} // namespace views
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_TAKE_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/take_while_view.h b/libcxx/include/__cxx03/__ranges/take_while_view.h
new file mode 100644
index 00000000000000..77ea9f7bb81316
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/take_while_view.h
@@ -0,0 +1,170 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_TAKE_WHILE_VIEW_H
+#define _LIBCPP___RANGES_TAKE_WHILE_VIEW_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/movable_box.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/maybe_const.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <view _View, class _Pred>
+ requires input_range<_View> && is_object_v<_Pred> && indirect_unary_predicate<const _Pred, iterator_t<_View>>
+class _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS take_while_view : public view_interface<take_while_view<_View, _Pred>> {
+ template <bool>
+ class __sentinel;
+
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+ _LIBCPP_NO_UNIQUE_ADDRESS __movable_box<_Pred> __pred_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI take_while_view()
+ requires default_initializable<_View> && default_initializable<_Pred>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 take_while_view(_View __base, _Pred __pred)
+ : __base_(std::move(__base)), __pred_(std::in_place, std::move(__pred)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Pred& pred() const { return *__pred_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
+ requires(!__simple_view<_View>)
+ {
+ return ranges::begin(__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires range<const _View> && indirect_unary_predicate<const _Pred, iterator_t<const _View>>
+ {
+ return ranges::begin(__base_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end()
+ requires(!__simple_view<_View>)
+ {
+ return __sentinel</*_Const=*/false>(ranges::end(__base_), std::addressof(*__pred_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires range<const _View> && indirect_unary_predicate<const _Pred, iterator_t<const _View>>
+ {
+ return __sentinel</*_Const=*/true>(ranges::end(__base_), std::addressof(*__pred_));
+ }
+};
+
+template <class _Range, class _Pred>
+take_while_view(_Range&&, _Pred) -> take_while_view<views::all_t<_Range>, _Pred>;
+
+template <view _View, class _Pred>
+ requires input_range<_View> && is_object_v<_Pred> && indirect_unary_predicate<const _Pred, iterator_t<_View>>
+template <bool _Const>
+class take_while_view<_View, _Pred>::__sentinel {
+ using _Base = __maybe_const<_Const, _View>;
+
+ sentinel_t<_Base> __end_ = sentinel_t<_Base>();
+ const _Pred* __pred_ = nullptr;
+
+ friend class __sentinel<!_Const>;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(sentinel_t<_Base> __end, const _Pred* __pred)
+ : __end_(std::move(__end)), __pred_(__pred) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __s)
+ requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
+ : __end_(std::move(__s.__end_)), __pred_(__s.__pred_) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Base> base() const { return __end_; }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const iterator_t<_Base>& __x, const __sentinel& __y) {
+ return __x == __y.__end_ || !std::invoke(*__y.__pred_, *__x);
+ }
+
+ template <bool _OtherConst = !_Const>
+ requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool
+ operator==(const iterator_t<__maybe_const<_OtherConst, _View>>& __x, const __sentinel& __y) {
+ return __x == __y.__end_ || !std::invoke(*__y.__pred_, *__x);
+ }
+};
+
+namespace views {
+namespace __take_while {
+
+struct __fn {
+ template <class _Range, class _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Pred&& __pred) const
+ noexcept(noexcept(/**/ take_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))))
+ -> decltype(/*--*/ take_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))) {
+ return /*-------------*/ take_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred));
+ }
+
+ template <class _Pred>
+ requires constructible_from<decay_t<_Pred>, _Pred>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Pred&& __pred) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Pred>, _Pred>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Pred>(__pred)));
+ }
+};
+
+} // namespace __take_while
+
+inline namespace __cpo {
+inline constexpr auto take_while = __take_while::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_TAKE_WHILE_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/to.h b/libcxx/include/__cxx03/__ranges/to.h
new file mode 100644
index 00000000000000..e0abe6290b8f7d
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/to.h
@@ -0,0 +1,245 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_TO_H
+#define _LIBCPP___RANGES_TO_H
+
+#include <__algorithm/ranges_copy.h>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/insert_iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/from_range.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/ref_view.h>
+#include <__ranges/size.h>
+#include <__ranges/transform_view.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_volatile.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+namespace ranges {
+
+template <class _Container>
+constexpr bool __reservable_container =
+ sized_range<_Container> && requires(_Container& __c, range_size_t<_Container> __n) {
+ __c.reserve(__n);
+ { __c.capacity() } -> same_as<decltype(__n)>;
+ { __c.max_size() } -> same_as<decltype(__n)>;
+ };
+
+template <class _Container, class _Ref>
+constexpr bool __container_insertable = requires(_Container& __c, _Ref&& __ref) {
+ requires(
+ requires { __c.push_back(std::forward<_Ref>(__ref)); } ||
+ requires { __c.insert(__c.end(), std::forward<_Ref>(__ref)); });
+};
+
+template <class _Ref, class _Container>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __container_inserter(_Container& __c) {
+ if constexpr (requires { __c.push_back(std::declval<_Ref>()); }) {
+ return std::back_inserter(__c);
+ } else {
+ return std::inserter(__c, __c.end());
+ }
+}
+
+// Note: making this a concept allows short-circuiting the second condition.
+template <class _Container, class _Range>
+concept __try_non_recursive_conversion =
+ !input_range<_Container> || convertible_to<range_reference_t<_Range>, range_value_t<_Container>>;
+
+template <class _Container, class _Range, class... _Args>
+concept __constructible_from_iter_pair =
+ common_range<_Range> && requires { typename iterator_traits<iterator_t<_Range>>::iterator_category; } &&
+ derived_from<typename iterator_traits<iterator_t<_Range>>::iterator_category, input_iterator_tag> &&
+ constructible_from<_Container, iterator_t<_Range>, sentinel_t<_Range>, _Args...>;
+
+template <class>
+concept __always_false = false;
+
+// `ranges::to` base template -- the `_Container` type is a simple type template parameter.
+template <class _Container, input_range _Range, class... _Args>
+ requires(!view<_Container>)
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Container to(_Range&& __range, _Args&&... __args) {
+ // Mandates: C is a cv-unqualified class type.
+ static_assert(!is_const_v<_Container>, "The target container cannot be const-qualified, please remove the const");
+ static_assert(
+ !is_volatile_v<_Container>, "The target container cannot be volatile-qualified, please remove the volatile");
+
+ // First see if the non-recursive case applies -- the conversion target is either:
+ // - a range with a convertible value type;
+ // - a non-range type which might support being created from the input argument(s) (e.g. an `optional`).
+ if constexpr (__try_non_recursive_conversion<_Container, _Range>) {
+ // Case 1 -- construct directly from the given range.
+ if constexpr (constructible_from<_Container, _Range, _Args...>) {
+ return _Container(std::forward<_Range>(__range), std::forward<_Args>(__args)...);
+ }
+
+ // Case 2 -- construct using the `from_range_t` tagged constructor.
+ else if constexpr (constructible_from<_Container, from_range_t, _Range, _Args...>) {
+ return _Container(from_range, std::forward<_Range>(__range), std::forward<_Args>(__args)...);
+ }
+
+ // Case 3 -- construct from a begin-end iterator pair.
+ else if constexpr (__constructible_from_iter_pair<_Container, _Range, _Args...>) {
+ return _Container(ranges::begin(__range), ranges::end(__range), std::forward<_Args>(__args)...);
+ }
+
+ // Case 4 -- default-construct (or construct from the extra arguments) and insert, reserving the size if possible.
+ else if constexpr (constructible_from<_Container, _Args...> &&
+ __container_insertable<_Container, range_reference_t<_Range>>) {
+ _Container __result(std::forward<_Args>(__args)...);
+ if constexpr (sized_range<_Range> && __reservable_container<_Container>) {
+ __result.reserve(static_cast<range_size_t<_Container>>(ranges::size(__range)));
+ }
+
+ ranges::copy(__range, ranges::__container_inserter<range_reference_t<_Range>>(__result));
+
+ return __result;
+
+ } else {
+ static_assert(__always_false<_Container>, "ranges::to: unable to convert to the given container type.");
+ }
+
+ // Try the recursive case.
+ } else if constexpr (input_range<range_reference_t<_Range>>) {
+ return ranges::to<_Container>(
+ ref_view(__range) | views::transform([](auto&& __elem) {
+ return ranges::to<range_value_t<_Container>>(std::forward<decltype(__elem)>(__elem));
+ }),
+ std::forward<_Args>(__args)...);
+
+ } else {
+ static_assert(__always_false<_Container>, "ranges::to: unable to convert to the given container type.");
+ }
+}
+
+template <class _Range>
+struct __minimal_input_iterator {
+ using iterator_category = input_iterator_tag;
+ using value_type = range_value_t<_Range>;
+ using difference_type = ptrdiff_t;
+ using pointer = add_pointer_t<range_reference_t<_Range>>;
+ using reference = range_reference_t<_Range>;
+
+ reference operator*() const;
+ pointer operator->() const;
+ __minimal_input_iterator& operator++();
+ __minimal_input_iterator operator++(int);
+ bool operator==(const __minimal_input_iterator&) const;
+};
+
+// Deduces the full type of the container from the given template template parameter.
+template <template <class...> class _Container, input_range _Range, class... _Args>
+struct _Deducer {
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __deduce_func() {
+ using _InputIter = __minimal_input_iterator<_Range>;
+
+ // Case 1 -- can construct directly from the given range.
+ if constexpr (requires { _Container(std::declval<_Range>(), std::declval<_Args>()...); }) {
+ using _Result = decltype( //
+ _Container(std::declval<_Range>(), std::declval<_Args>()...));
+ return type_identity<_Result>{};
+
+ // Case 2 -- can construct from the given range using the `from_range_t` tagged constructor.
+ } else if constexpr ( //
+ requires { _Container(from_range, std::declval<_Range>(), std::declval<_Args>()...); }) {
+ using _Result = //
+ decltype(_Container(from_range, std::declval<_Range>(), std::declval<_Args>()...));
+ return type_identity<_Result>{};
+
+ // Case 3 -- can construct from a begin-end iterator pair.
+ } else if constexpr ( //
+ requires { _Container(std::declval<_InputIter>(), std::declval<_InputIter>(), std::declval<_Args>()...); }) {
+ using _Result =
+ decltype(_Container(std::declval<_InputIter>(), std::declval<_InputIter>(), std::declval<_Args>()...));
+ return type_identity<_Result>{};
+
+ } else {
+ static_assert(__always_false<_Range>,
+ "ranges::to: unable to deduce the container type from the template template argument.");
+ }
+ }
+
+ using type = typename decltype(__deduce_func())::type;
+};
+
+// `ranges::to` specialization -- `_Container` is a template template parameter requiring deduction to figure out the
+// container element type.
+template <template <class...> class _Container, input_range _Range, class... _Args>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto to(_Range&& __range, _Args&&... __args) {
+ using _DeduceExpr = typename _Deducer<_Container, _Range, _Args...>::type;
+ return ranges::to<_DeduceExpr>(std::forward<_Range>(__range), std::forward<_Args>(__args)...);
+}
+
+// Range adaptor closure object 1 -- wrapping the `ranges::to` version where `_Container` is a simple type template
+// parameter.
+template <class _Container, class... _Args>
+ requires(!view<_Container>)
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto to(_Args&&... __args) {
+ // Mandates: C is a cv-unqualified class type.
+ static_assert(!is_const_v<_Container>, "The target container cannot be const-qualified, please remove the const");
+ static_assert(
+ !is_volatile_v<_Container>, "The target container cannot be volatile-qualified, please remove the volatile");
+
+ auto __to_func = []<input_range _Range, class... _Tail>(_Range&& __range, _Tail&&... __tail) static
+ requires requires { //
+ /**/ ranges::to<_Container>(std::forward<_Range>(__range), std::forward<_Tail>(__tail)...);
+ }
+ { return ranges::to<_Container>(std::forward<_Range>(__range), std::forward<_Tail>(__tail)...); };
+
+ return __range_adaptor_closure_t(std::__bind_back(__to_func, std::forward<_Args>(__args)...));
+}
+
+// Range adaptor closure object 2 -- wrapping the `ranges::to` version where `_Container` is a template template
+// parameter.
+template <template <class...> class _Container, class... _Args>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto to(_Args&&... __args) {
+ // clang-format off
+ auto __to_func = []<input_range _Range, class... _Tail,
+ class _DeducedExpr = typename _Deducer<_Container, _Range, _Tail...>::type>
+ (_Range&& __range, _Tail&& ... __tail) static
+ requires requires { //
+ /**/ ranges::to<_DeducedExpr>(std::forward<_Range>(__range), std::forward<_Tail>(__tail)...);
+ }
+ {
+ return ranges::to<_DeducedExpr>(std::forward<_Range>(__range), std::forward<_Tail>(__tail)...);
+ };
+ // clang-format on
+
+ return __range_adaptor_closure_t(std::__bind_back(__to_func, std::forward<_Args>(__args)...));
+}
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_TO_H
diff --git a/libcxx/include/__cxx03/__ranges/transform_view.h b/libcxx/include/__cxx03/__ranges/transform_view.h
new file mode 100644
index 00000000000000..bcce389c0e6809
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/transform_view.h
@@ -0,0 +1,417 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_TRANSFORM_VIEW_H
+#define _LIBCPP___RANGES_TRANSFORM_VIEW_H
+
+#include <__compare/three_way_comparable.h>
+#include <__concepts/constructible.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/copyable.h>
+#include <__concepts/derived_from.h>
+#include <__concepts/equality_comparable.h>
+#include <__concepts/invocable.h>
+#include <__config>
+#include <__functional/bind_back.h>
+#include <__functional/invoke.h>
+#include <__functional/perfect_forward.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/empty.h>
+#include <__ranges/movable_box.h>
+#include <__ranges/range_adaptor.h>
+#include <__ranges/size.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/maybe_const.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _Fn, class _View>
+concept __regular_invocable_with_range_ref = regular_invocable<_Fn, range_reference_t<_View>>;
+
+template <class _View, class _Fn>
+concept __transform_view_constraints =
+ view<_View> && is_object_v<_Fn> && regular_invocable<_Fn&, range_reference_t<_View>> &&
+ __can_reference<invoke_result_t<_Fn&, range_reference_t<_View>>>;
+
+# if _LIBCPP_STD_VER >= 23
+template <input_range _View, move_constructible _Fn>
+# else
+template <input_range _View, copy_constructible _Fn>
+# endif
+ requires __transform_view_constraints<_View, _Fn>
+class _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS transform_view : public view_interface<transform_view<_View, _Fn>> {
+ template <bool>
+ class __iterator;
+ template <bool>
+ class __sentinel;
+
+ _LIBCPP_NO_UNIQUE_ADDRESS __movable_box<_Fn> __func_;
+ _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
+
+public:
+ _LIBCPP_HIDE_FROM_ABI transform_view()
+ requires default_initializable<_View> && default_initializable<_Fn>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 transform_view(_View __base, _Fn __func)
+ : __func_(std::in_place, std::move(__func)), __base_(std::move(__base)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
+ requires copy_constructible<_View>
+ {
+ return __base_;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator<false> begin() { return __iterator<false>{*this, ranges::begin(__base_)}; }
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator<true> begin() const
+ requires range<const _View> && __regular_invocable_with_range_ref<const _Fn&, const _View>
+ {
+ return __iterator<true>(*this, ranges::begin(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __sentinel<false> end() { return __sentinel<false>(ranges::end(__base_)); }
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator<false> end()
+ requires common_range<_View>
+ {
+ return __iterator<false>(*this, ranges::end(__base_));
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr __sentinel<true> end() const
+ requires range<const _View> && __regular_invocable_with_range_ref<const _Fn&, const _View>
+ {
+ return __sentinel<true>(ranges::end(__base_));
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator<true> end() const
+ requires common_range<const _View> && __regular_invocable_with_range_ref<const _Fn&, const _View>
+ {
+ return __iterator<true>(*this, ranges::end(__base_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires sized_range<_View>
+ {
+ return ranges::size(__base_);
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires sized_range<const _View>
+ {
+ return ranges::size(__base_);
+ }
+};
+
+template <class _Range, class _Fn>
+transform_view(_Range&&, _Fn) -> transform_view<views::all_t<_Range>, _Fn>;
+
+template <class _View>
+struct __transform_view_iterator_concept {
+ using type = input_iterator_tag;
+};
+
+template <random_access_range _View>
+struct __transform_view_iterator_concept<_View> {
+ using type = random_access_iterator_tag;
+};
+
+template <bidirectional_range _View>
+struct __transform_view_iterator_concept<_View> {
+ using type = bidirectional_iterator_tag;
+};
+
+template <forward_range _View>
+struct __transform_view_iterator_concept<_View> {
+ using type = forward_iterator_tag;
+};
+
+template <class, class>
+struct __transform_view_iterator_category_base {};
+
+template <forward_range _View, class _Fn>
+struct __transform_view_iterator_category_base<_View, _Fn> {
+ using _Cat = typename iterator_traits<iterator_t<_View>>::iterator_category;
+
+ using iterator_category =
+ conditional_t< is_reference_v<invoke_result_t<_Fn&, range_reference_t<_View>>>,
+ conditional_t< derived_from<_Cat, contiguous_iterator_tag>, random_access_iterator_tag, _Cat >,
+ input_iterator_tag >;
+};
+
+# if _LIBCPP_STD_VER >= 23
+template <input_range _View, move_constructible _Fn>
+# else
+template <input_range _View, copy_constructible _Fn>
+# endif
+ requires __transform_view_constraints<_View, _Fn>
+template <bool _Const>
+class transform_view<_View, _Fn>::__iterator : public __transform_view_iterator_category_base<_View, _Fn> {
+
+ using _Parent = __maybe_const<_Const, transform_view>;
+ using _Base = __maybe_const<_Const, _View>;
+
+ _Parent* __parent_ = nullptr;
+
+ template <bool>
+ friend class transform_view<_View, _Fn>::__iterator;
+
+ template <bool>
+ friend class transform_view<_View, _Fn>::__sentinel;
+
+public:
+ iterator_t<_Base> __current_ = iterator_t<_Base>();
+
+ using iterator_concept = typename __transform_view_iterator_concept<_View>::type;
+ using value_type = remove_cvref_t<invoke_result_t<_Fn&, range_reference_t<_Base>>>;
+ using difference_type = range_difference_t<_Base>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator()
+ requires default_initializable<iterator_t<_Base>>
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(_Parent& __parent, iterator_t<_Base> __current)
+ : __parent_(std::addressof(__parent)), __current_(std::move(__current)) {}
+
+ // Note: `__i` should always be `__iterator<false>`, but directly using
+ // `__iterator<false>` is ill-formed when `_Const` is false
+ // (see http://wg21.link/class.copy.ctor#5).
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(__iterator<!_Const> __i)
+ requires _Const && convertible_to<iterator_t<_View>, iterator_t<_Base>>
+ : __parent_(__i.__parent_), __current_(std::move(__i.__current_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const iterator_t<_Base>& base() const& noexcept { return __current_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_Base> base() && { return std::move(__current_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const
+ noexcept(noexcept(std::invoke(*__parent_->__func_, *__current_))) {
+ return std::invoke(*__parent_->__func_, *__current_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ ++__current_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator++(int) { ++__current_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int)
+ requires forward_range<_Base>
+ {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--()
+ requires bidirectional_range<_Base>
+ {
+ --__current_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int)
+ requires bidirectional_range<_Base>
+ {
+ auto __tmp = *this;
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator+=(difference_type __n)
+ requires random_access_range<_Base>
+ {
+ __current_ += __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator-=(difference_type __n)
+ requires random_access_range<_Base>
+ {
+ __current_ -= __n;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator[](difference_type __n) const
+ noexcept(noexcept(std::invoke(*__parent_->__func_, __current_[__n])))
+ requires random_access_range<_Base>
+ {
+ return std::invoke(*__parent_->__func_, __current_[__n]);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
+ requires equality_comparable<iterator_t<_Base>>
+ {
+ return __x.__current_ == __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return __x.__current_ < __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return __x.__current_ > __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return __x.__current_ <= __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base>
+ {
+ return __x.__current_ >= __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y)
+ requires random_access_range<_Base> && three_way_comparable<iterator_t<_Base>>
+ {
+ return __x.__current_ <=> __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(__iterator __i, difference_type __n)
+ requires random_access_range<_Base>
+ {
+ return __iterator{*__i.__parent_, __i.__current_ + __n};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(difference_type __n, __iterator __i)
+ requires random_access_range<_Base>
+ {
+ return __iterator{*__i.__parent_, __i.__current_ + __n};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator-(__iterator __i, difference_type __n)
+ requires random_access_range<_Base>
+ {
+ return __iterator{*__i.__parent_, __i.__current_ - __n};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y)
+ requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>>
+ {
+ return __x.__current_ - __y.__current_;
+ }
+};
+
+# if _LIBCPP_STD_VER >= 23
+template <input_range _View, move_constructible _Fn>
+# else
+template <input_range _View, copy_constructible _Fn>
+# endif
+ requires __transform_view_constraints<_View, _Fn>
+template <bool _Const>
+class transform_view<_View, _Fn>::__sentinel {
+ using _Parent = __maybe_const<_Const, transform_view>;
+ using _Base = __maybe_const<_Const, _View>;
+
+ sentinel_t<_Base> __end_ = sentinel_t<_Base>();
+
+ template <bool>
+ friend class transform_view<_View, _Fn>::__iterator;
+
+ template <bool>
+ friend class transform_view<_View, _Fn>::__sentinel;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(sentinel_t<_Base> __end) : __end_(__end) {}
+
+ // Note: `__i` should always be `__sentinel<false>`, but directly using
+ // `__sentinel<false>` is ill-formed when `_Const` is false
+ // (see http://wg21.link/class.copy.ctor#5).
+ _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __i)
+ requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
+ : __end_(std::move(__i.__end_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Base> base() const { return __end_; }
+
+ template <bool _OtherConst>
+ requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
+ return __x.__current_ == __y.__end_;
+ }
+
+ template <bool _OtherConst>
+ requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr range_difference_t<__maybe_const<_OtherConst, _View>>
+ operator-(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
+ return __x.__current_ - __y.__end_;
+ }
+
+ template <bool _OtherConst>
+ requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
+ _LIBCPP_HIDE_FROM_ABI friend constexpr range_difference_t<__maybe_const<_OtherConst, _View>>
+ operator-(const __sentinel& __x, const __iterator<_OtherConst>& __y) {
+ return __x.__end_ - __y.__current_;
+ }
+};
+
+namespace views {
+namespace __transform {
+struct __fn {
+ template <class _Range, class _Fn>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Fn&& __f) const
+ noexcept(noexcept(transform_view(std::forward<_Range>(__range), std::forward<_Fn>(__f))))
+ -> decltype(transform_view(std::forward<_Range>(__range), std::forward<_Fn>(__f))) {
+ return transform_view(std::forward<_Range>(__range), std::forward<_Fn>(__f));
+ }
+
+ template <class _Fn>
+ requires constructible_from<decay_t<_Fn>, _Fn>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Fn&& __f) const
+ noexcept(is_nothrow_constructible_v<decay_t<_Fn>, _Fn>) {
+ return __range_adaptor_closure_t(std::__bind_back(*this, std::forward<_Fn>(__f)));
+ }
+};
+} // namespace __transform
+
+inline namespace __cpo {
+inline constexpr auto transform = __transform::__fn{};
+} // namespace __cpo
+} // namespace views
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_TRANSFORM_VIEW_H
diff --git a/libcxx/include/__cxx03/__ranges/view_interface.h b/libcxx/include/__cxx03/__ranges/view_interface.h
new file mode 100644
index 00000000000000..3bcfbaf3a2f9ed
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/view_interface.h
@@ -0,0 +1,170 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_VIEW_INTERFACE_H
+#define _LIBCPP___RANGES_VIEW_INTERFACE_H
+
+#include <__assert>
+#include <__concepts/derived_from.h>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/prev.h>
+#include <__memory/pointer_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/empty.h>
+#include <__ranges/size.h>
+#include <__type_traits/is_class.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+template <class _Derived>
+ requires is_class_v<_Derived> && same_as<_Derived, remove_cv_t<_Derived>>
+class view_interface {
+ _LIBCPP_HIDE_FROM_ABI constexpr _Derived& __derived() noexcept {
+ static_assert(sizeof(_Derived) && derived_from<_Derived, view_interface> && view<_Derived>);
+ return static_cast<_Derived&>(*this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr _Derived const& __derived() const noexcept {
+ static_assert(sizeof(_Derived) && derived_from<_Derived, view_interface> && view<_Derived>);
+ return static_cast<_Derived const&>(*this);
+ }
+
+public:
+ template <class _D2 = _Derived>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty()
+ requires sized_range<_D2> || forward_range<_D2>
+ {
+ if constexpr (sized_range<_D2>) {
+ return ranges::size(__derived()) == 0;
+ } else {
+ return ranges::begin(__derived()) == ranges::end(__derived());
+ }
+ }
+
+ template <class _D2 = _Derived>
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const
+ requires sized_range<const _D2> || forward_range<const _D2>
+ {
+ if constexpr (sized_range<const _D2>) {
+ return ranges::size(__derived()) == 0;
+ } else {
+ return ranges::begin(__derived()) == ranges::end(__derived());
+ }
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool()
+ requires requires(_D2& __t) { ranges::empty(__t); }
+ {
+ return !ranges::empty(__derived());
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const
+ requires requires(const _D2& __t) { ranges::empty(__t); }
+ {
+ return !ranges::empty(__derived());
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto data()
+ requires contiguous_iterator<iterator_t<_D2>>
+ {
+ return std::to_address(ranges::begin(__derived()));
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto data() const
+ requires range<const _D2> && contiguous_iterator<iterator_t<const _D2>>
+ {
+ return std::to_address(ranges::begin(__derived()));
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires forward_range<_D2> && sized_sentinel_for<sentinel_t<_D2>, iterator_t<_D2>>
+ {
+ return std::__to_unsigned_like(ranges::end(__derived()) - ranges::begin(__derived()));
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires forward_range<const _D2> && sized_sentinel_for<sentinel_t<const _D2>, iterator_t<const _D2>>
+ {
+ return std::__to_unsigned_like(ranges::end(__derived()) - ranges::begin(__derived()));
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) front()
+ requires forward_range<_D2>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !empty(), "Precondition `!empty()` not satisfied. `.front()` called on an empty view.");
+ return *ranges::begin(__derived());
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) front() const
+ requires forward_range<const _D2>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !empty(), "Precondition `!empty()` not satisfied. `.front()` called on an empty view.");
+ return *ranges::begin(__derived());
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) back()
+ requires bidirectional_range<_D2> && common_range<_D2>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !empty(), "Precondition `!empty()` not satisfied. `.back()` called on an empty view.");
+ return *ranges::prev(ranges::end(__derived()));
+ }
+
+ template <class _D2 = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) back() const
+ requires bidirectional_range<const _D2> && common_range<const _D2>
+ {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ !empty(), "Precondition `!empty()` not satisfied. `.back()` called on an empty view.");
+ return *ranges::prev(ranges::end(__derived()));
+ }
+
+ template <random_access_range _RARange = _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator[](range_difference_t<_RARange> __index) {
+ return ranges::begin(__derived())[__index];
+ }
+
+ template <random_access_range _RARange = const _Derived>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator[](range_difference_t<_RARange> __index) const {
+ return ranges::begin(__derived())[__index];
+ }
+};
+
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_VIEW_INTERFACE_H
diff --git a/libcxx/include/__cxx03/__ranges/views.h b/libcxx/include/__cxx03/__ranges/views.h
new file mode 100644
index 00000000000000..a4de2a5e52a9de
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/views.h
@@ -0,0 +1,35 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_VIEWS
+#define _LIBCPP___RANGES_VIEWS
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+namespace ranges {
+
+namespace views {}
+
+} // namespace ranges
+
+namespace views = ranges::views;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANGES_VIEWS
diff --git a/libcxx/include/__cxx03/__ranges/zip_view.h b/libcxx/include/__cxx03/__ranges/zip_view.h
new file mode 100644
index 00000000000000..fe3c87a9306fe9
--- /dev/null
+++ b/libcxx/include/__cxx03/__ranges/zip_view.h
@@ -0,0 +1,516 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_ZIP_VIEW_H
+#define _LIBCPP___RANGES_ZIP_VIEW_H
+
+#include <__config>
+
+#include <__algorithm/ranges_min.h>
+#include <__compare/three_way_comparable.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/equality_comparable.h>
+#include <__functional/invoke.h>
+#include <__functional/operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/iter_move.h>
+#include <__iterator/iter_swap.h>
+#include <__iterator/iterator_traits.h>
+#include <__ranges/access.h>
+#include <__ranges/all.h>
+#include <__ranges/concepts.h>
+#include <__ranges/empty_view.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/size.h>
+#include <__ranges/view_interface.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/make_unsigned.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/integer_sequence.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+namespace ranges {
+
+template <class... _Ranges>
+concept __zip_is_common =
+ (sizeof...(_Ranges) == 1 && (common_range<_Ranges> && ...)) ||
+ (!(bidirectional_range<_Ranges> && ...) && (common_range<_Ranges> && ...)) ||
+ ((random_access_range<_Ranges> && ...) && (sized_range<_Ranges> && ...));
+
+template <typename _Tp, typename _Up>
+auto __tuple_or_pair_test() -> pair<_Tp, _Up>;
+
+template <typename... _Types>
+ requires(sizeof...(_Types) != 2)
+auto __tuple_or_pair_test() -> tuple<_Types...>;
+
+template <class... _Types>
+using __tuple_or_pair = decltype(__tuple_or_pair_test<_Types...>());
+
+template <class _Fun, class _Tuple>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __tuple_transform(_Fun&& __f, _Tuple&& __tuple) {
+ return std::apply(
+ [&]<class... _Types>(_Types&&... __elements) {
+ return __tuple_or_pair<invoke_result_t<_Fun&, _Types>...>(
+ std::invoke(__f, std::forward<_Types>(__elements))...);
+ },
+ std::forward<_Tuple>(__tuple));
+}
+
+template <class _Fun, class _Tuple>
+_LIBCPP_HIDE_FROM_ABI constexpr void __tuple_for_each(_Fun&& __f, _Tuple&& __tuple) {
+ std::apply(
+ [&]<class... _Types>(_Types&&... __elements) {
+ (static_cast<void>(std::invoke(__f, std::forward<_Types>(__elements))), ...);
+ },
+ std::forward<_Tuple>(__tuple));
+}
+
+template <class _Fun, class _Tuple1, class _Tuple2, size_t... _Indices>
+_LIBCPP_HIDE_FROM_ABI constexpr __tuple_or_pair<
+ invoke_result_t<_Fun&,
+ typename tuple_element<_Indices, remove_cvref_t<_Tuple1>>::type,
+ typename tuple_element<_Indices, remove_cvref_t<_Tuple2>>::type>...>
+__tuple_zip_transform(_Fun&& __f, _Tuple1&& __tuple1, _Tuple2&& __tuple2, index_sequence<_Indices...>) {
+ return {std::invoke(__f,
+ std::get<_Indices>(std::forward<_Tuple1>(__tuple1)),
+ std::get<_Indices>(std::forward<_Tuple2>(__tuple2)))...};
+}
+
+template <class _Fun, class _Tuple1, class _Tuple2>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __tuple_zip_transform(_Fun&& __f, _Tuple1&& __tuple1, _Tuple2&& __tuple2) {
+ return ranges::__tuple_zip_transform(
+ __f,
+ std::forward<_Tuple1>(__tuple1),
+ std::forward<_Tuple2>(__tuple2),
+ std::make_index_sequence<tuple_size<remove_cvref_t<_Tuple1>>::value>());
+}
+
+template <class _Fun, class _Tuple1, class _Tuple2, size_t... _Indices>
+_LIBCPP_HIDE_FROM_ABI constexpr void
+__tuple_zip_for_each(_Fun&& __f, _Tuple1&& __tuple1, _Tuple2&& __tuple2, index_sequence<_Indices...>) {
+ (std::invoke(
+ __f, std::get<_Indices>(std::forward<_Tuple1>(__tuple1)), std::get<_Indices>(std::forward<_Tuple2>(__tuple2))),
+ ...);
+}
+
+template <class _Fun, class _Tuple1, class _Tuple2>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __tuple_zip_for_each(_Fun&& __f, _Tuple1&& __tuple1, _Tuple2&& __tuple2) {
+ return ranges::__tuple_zip_for_each(
+ __f,
+ std::forward<_Tuple1>(__tuple1),
+ std::forward<_Tuple2>(__tuple2),
+ std::make_index_sequence<tuple_size<remove_cvref_t<_Tuple1>>::value>());
+}
+
+template <class _Tuple1, class _Tuple2>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __tuple_any_equals(const _Tuple1& __tuple1, const _Tuple2& __tuple2) {
+ const auto __equals = ranges::__tuple_zip_transform(std::equal_to<>(), __tuple1, __tuple2);
+ return std::apply([](auto... __bools) { return (__bools || ...); }, __equals);
+}
+
+// abs in cstdlib is not constexpr
+// TODO : remove __abs once P0533R9 is implemented.
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp __abs(_Tp __t) {
+ return __t < 0 ? -__t : __t;
+}
+
+template <input_range... _Views>
+ requires(view<_Views> && ...) && (sizeof...(_Views) > 0)
+class zip_view : public view_interface<zip_view<_Views...>> {
+ _LIBCPP_NO_UNIQUE_ADDRESS tuple<_Views...> __views_;
+
+ template <bool>
+ class __iterator;
+
+ template <bool>
+ class __sentinel;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI zip_view() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit zip_view(_Views... __views) : __views_(std::move(__views)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
+ requires(!(__simple_view<_Views> && ...))
+ {
+ return __iterator<false>(ranges::__tuple_transform(ranges::begin, __views_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
+ requires(range<const _Views> && ...)
+ {
+ return __iterator<true>(ranges::__tuple_transform(ranges::begin, __views_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end()
+ requires(!(__simple_view<_Views> && ...))
+ {
+ if constexpr (!__zip_is_common<_Views...>) {
+ return __sentinel<false>(ranges::__tuple_transform(ranges::end, __views_));
+ } else if constexpr ((random_access_range<_Views> && ...)) {
+ return begin() + iter_difference_t<__iterator<false>>(size());
+ } else {
+ return __iterator<false>(ranges::__tuple_transform(ranges::end, __views_));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
+ requires(range<const _Views> && ...)
+ {
+ if constexpr (!__zip_is_common<const _Views...>) {
+ return __sentinel<true>(ranges::__tuple_transform(ranges::end, __views_));
+ } else if constexpr ((random_access_range<const _Views> && ...)) {
+ return begin() + iter_difference_t<__iterator<true>>(size());
+ } else {
+ return __iterator<true>(ranges::__tuple_transform(ranges::end, __views_));
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size()
+ requires(sized_range<_Views> && ...)
+ {
+ return std::apply(
+ [](auto... __sizes) {
+ using _CT = make_unsigned_t<common_type_t<decltype(__sizes)...>>;
+ return ranges::min({_CT(__sizes)...});
+ },
+ ranges::__tuple_transform(ranges::size, __views_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
+ requires(sized_range<const _Views> && ...)
+ {
+ return std::apply(
+ [](auto... __sizes) {
+ using _CT = make_unsigned_t<common_type_t<decltype(__sizes)...>>;
+ return ranges::min({_CT(__sizes)...});
+ },
+ ranges::__tuple_transform(ranges::size, __views_));
+ }
+};
+
+template <class... _Ranges>
+zip_view(_Ranges&&...) -> zip_view<views::all_t<_Ranges>...>;
+
+template <bool _Const, class... _Views>
+concept __zip_all_random_access = (random_access_range<__maybe_const<_Const, _Views>> && ...);
+
+template <bool _Const, class... _Views>
+concept __zip_all_bidirectional = (bidirectional_range<__maybe_const<_Const, _Views>> && ...);
+
+template <bool _Const, class... _Views>
+concept __zip_all_forward = (forward_range<__maybe_const<_Const, _Views>> && ...);
+
+template <bool _Const, class... _Views>
+consteval auto __get_zip_view_iterator_tag() {
+ if constexpr (__zip_all_random_access<_Const, _Views...>) {
+ return random_access_iterator_tag();
+ } else if constexpr (__zip_all_bidirectional<_Const, _Views...>) {
+ return bidirectional_iterator_tag();
+ } else if constexpr (__zip_all_forward<_Const, _Views...>) {
+ return forward_iterator_tag();
+ } else {
+ return input_iterator_tag();
+ }
+}
+
+template <bool _Const, class... _Views>
+struct __zip_view_iterator_category_base {};
+
+template <bool _Const, class... _Views>
+ requires __zip_all_forward<_Const, _Views...>
+struct __zip_view_iterator_category_base<_Const, _Views...> {
+ using iterator_category = input_iterator_tag;
+};
+
+template <input_range... _Views>
+ requires(view<_Views> && ...) && (sizeof...(_Views) > 0)
+template <bool _Const>
+class zip_view<_Views...>::__iterator : public __zip_view_iterator_category_base<_Const, _Views...> {
+ __tuple_or_pair<iterator_t<__maybe_const<_Const, _Views>>...> __current_;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(
+ __tuple_or_pair<iterator_t<__maybe_const<_Const, _Views>>...> __current)
+ : __current_(std::move(__current)) {}
+
+ template <bool>
+ friend class zip_view<_Views...>::__iterator;
+
+ template <bool>
+ friend class zip_view<_Views...>::__sentinel;
+
+ friend class zip_view<_Views...>;
+
+public:
+ using iterator_concept = decltype(__get_zip_view_iterator_tag<_Const, _Views...>());
+ using value_type = __tuple_or_pair<range_value_t<__maybe_const<_Const, _Views>>...>;
+ using difference_type = common_type_t<range_difference_t<__maybe_const<_Const, _Views>>...>;
+
+ _LIBCPP_HIDE_FROM_ABI __iterator() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator(__iterator<!_Const> __i)
+ requires _Const && (convertible_to<iterator_t<_Views>, iterator_t<__maybe_const<_Const, _Views>>> && ...)
+ : __current_(std::move(__i.__current_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator*() const {
+ return ranges::__tuple_transform([](auto& __i) -> decltype(auto) { return *__i; }, __current_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
+ ranges::__tuple_for_each([](auto& __i) { ++__i; }, __current_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void operator++(int) { ++*this; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int)
+ requires __zip_all_forward<_Const, _Views...>
+ {
+ auto __tmp = *this;
+ ++*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--()
+ requires __zip_all_bidirectional<_Const, _Views...>
+ {
+ ranges::__tuple_for_each([](auto& __i) { --__i; }, __current_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int)
+ requires __zip_all_bidirectional<_Const, _Views...>
+ {
+ auto __tmp = *this;
+ --*this;
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator+=(difference_type __x)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ ranges::__tuple_for_each([&]<class _Iter>(_Iter& __i) { __i += iter_difference_t<_Iter>(__x); }, __current_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator-=(difference_type __x)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ ranges::__tuple_for_each([&]<class _Iter>(_Iter& __i) { __i -= iter_difference_t<_Iter>(__x); }, __current_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto operator[](difference_type __n) const
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ return ranges::__tuple_transform(
+ [&]<class _Iter>(_Iter& __i) -> decltype(auto) { return __i[iter_difference_t<_Iter>(__n)]; }, __current_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
+ requires(equality_comparable<iterator_t<__maybe_const<_Const, _Views>>> && ...)
+ {
+ if constexpr (__zip_all_bidirectional<_Const, _Views...>) {
+ return __x.__current_ == __y.__current_;
+ } else {
+ return ranges::__tuple_any_equals(__x.__current_, __y.__current_);
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(const __iterator& __x, const __iterator& __y)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ return __x.__current_ < __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(const __iterator& __x, const __iterator& __y)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ return __y < __x;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(const __iterator& __x, const __iterator& __y)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ return !(__y < __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(const __iterator& __x, const __iterator& __y)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ return !(__x < __y);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y)
+ requires __zip_all_random_access<_Const, _Views...> &&
+ (three_way_comparable<iterator_t<__maybe_const<_Const, _Views>>> && ...)
+ {
+ return __x.__current_ <=> __y.__current_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(const __iterator& __i, difference_type __n)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ auto __r = __i;
+ __r += __n;
+ return __r;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(difference_type __n, const __iterator& __i)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ return __i + __n;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator-(const __iterator& __i, difference_type __n)
+ requires __zip_all_random_access<_Const, _Views...>
+ {
+ auto __r = __i;
+ __r -= __n;
+ return __r;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y)
+ requires(sized_sentinel_for<iterator_t<__maybe_const<_Const, _Views>>, iterator_t<__maybe_const<_Const, _Views>>> &&
+ ...)
+ {
+ const auto __diffs = ranges::__tuple_zip_transform(minus<>(), __x.__current_, __y.__current_);
+ return std::apply(
+ [](auto... __ds) {
+ return ranges::min({difference_type(__ds)...}, [](auto __a, auto __b) {
+ return ranges::__abs(__a) < ranges::__abs(__b);
+ });
+ },
+ __diffs);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr auto iter_move(const __iterator& __i) noexcept(
+ (noexcept(ranges::iter_move(std::declval<const iterator_t<__maybe_const<_Const, _Views>>&>())) && ...) &&
+ (is_nothrow_move_constructible_v<range_rvalue_reference_t<__maybe_const<_Const, _Views>>> && ...)) {
+ return ranges::__tuple_transform(ranges::iter_move, __i.__current_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend constexpr void iter_swap(const __iterator& __l, const __iterator& __r) noexcept(
+ (noexcept(ranges::iter_swap(std::declval<const iterator_t<__maybe_const<_Const, _Views>>&>(),
+ std::declval<const iterator_t<__maybe_const<_Const, _Views>>&>())) &&
+ ...))
+ requires(indirectly_swappable<iterator_t<__maybe_const<_Const, _Views>>> && ...)
+ {
+ ranges::__tuple_zip_for_each(ranges::iter_swap, __l.__current_, __r.__current_);
+ }
+};
+
+template <input_range... _Views>
+ requires(view<_Views> && ...) && (sizeof...(_Views) > 0)
+template <bool _Const>
+class zip_view<_Views...>::__sentinel {
+ __tuple_or_pair<sentinel_t<__maybe_const<_Const, _Views>>...> __end_;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(
+ __tuple_or_pair<sentinel_t<__maybe_const<_Const, _Views>>...> __end)
+ : __end_(__end) {}
+
+ friend class zip_view<_Views...>;
+
+ // hidden friend cannot access private member of iterator because they are friends of friends
+ template <bool _OtherConst>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto)
+ __iter_current(zip_view<_Views...>::__iterator<_OtherConst> const& __it) {
+ return (__it.__current_);
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __i)
+ requires _Const && (convertible_to<sentinel_t<_Views>, sentinel_t<__maybe_const<_Const, _Views>>> && ...)
+ : __end_(std::move(__i.__end_)) {}
+
+ template <bool _OtherConst>
+ requires(sentinel_for<sentinel_t<__maybe_const<_Const, _Views>>, iterator_t<__maybe_const<_OtherConst, _Views>>> &&
+ ...)
+ _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
+ return ranges::__tuple_any_equals(__iter_current(__x), __y.__end_);
+ }
+
+ template <bool _OtherConst>
+ requires(
+ sized_sentinel_for<sentinel_t<__maybe_const<_Const, _Views>>, iterator_t<__maybe_const<_OtherConst, _Views>>> &&
+ ...)
+ _LIBCPP_HIDE_FROM_ABI friend constexpr common_type_t<range_difference_t<__maybe_const<_OtherConst, _Views>>...>
+ operator-(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
+ const auto __diffs = ranges::__tuple_zip_transform(minus<>(), __iter_current(__x), __y.__end_);
+ return std::apply(
+ [](auto... __ds) {
+ using _Diff = common_type_t<range_difference_t<__maybe_const<_OtherConst, _Views>>...>;
+ return ranges::min({_Diff(__ds)...}, [](auto __a, auto __b) {
+ return ranges::__abs(__a) < ranges::__abs(__b);
+ });
+ },
+ __diffs);
+ }
+
+ template <bool _OtherConst>
+ requires(
+ sized_sentinel_for<sentinel_t<__maybe_const<_Const, _Views>>, iterator_t<__maybe_const<_OtherConst, _Views>>> &&
+ ...)
+ _LIBCPP_HIDE_FROM_ABI friend constexpr common_type_t<range_difference_t<__maybe_const<_OtherConst, _Views>>...>
+ operator-(const __sentinel& __y, const __iterator<_OtherConst>& __x) {
+ return -(__x - __y);
+ }
+};
+
+template <class... _Views>
+inline constexpr bool enable_borrowed_range<zip_view<_Views...>> = (enable_borrowed_range<_Views> && ...);
+
+namespace views {
+namespace __zip {
+
+struct __fn {
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()() noexcept { return empty_view<tuple<>>{}; }
+
+ template <class... _Ranges>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto
+ operator()(_Ranges&&... __rs) noexcept(noexcept(zip_view<all_t<_Ranges&&>...>(std::forward<_Ranges>(__rs)...)))
+ -> decltype(zip_view<all_t<_Ranges&&>...>(std::forward<_Ranges>(__rs)...)) {
+ return zip_view<all_t<_Ranges>...>(std::forward<_Ranges>(__rs)...);
+ }
+};
+
+} // namespace __zip
+inline namespace __cpo {
+inline constexpr auto zip = __zip::__fn{};
+} // namespace __cpo
+} // namespace views
+} // namespace ranges
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_ZIP_VIEW_H
diff --git a/libcxx/include/__cxx03/__split_buffer b/libcxx/include/__cxx03/__split_buffer
new file mode 100644
index 00000000000000..bab724d1b8963b
--- /dev/null
+++ b/libcxx/include/__cxx03/__split_buffer
@@ -0,0 +1,585 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SPLIT_BUFFER
+#define _LIBCPP___SPLIT_BUFFER
+
+#include <__algorithm/max.h>
+#include <__algorithm/move.h>
+#include <__algorithm/move_backward.h>
+#include <__config>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/move_iterator.h>
+#include <__memory/allocate_at_least.h>
+#include <__memory/allocator.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/compressed_pair.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/swap_allocator.h>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// __split_buffer allocates a contiguous chunk of memory and stores objects in the range [__begin_, __end_).
+// It has uninitialized memory in the ranges [__first_, __begin_) and [__end_, __end_cap_.first()). That allows
+// it to grow both in the front and back without having to move the data.
+
+template <class _Tp, class _Allocator = allocator<_Tp> >
+struct __split_buffer {
+public:
+ using value_type = _Tp;
+ using allocator_type = _Allocator;
+ using __alloc_rr = __libcpp_remove_reference_t<allocator_type>;
+ using __alloc_traits = allocator_traits<__alloc_rr>;
+ using reference = value_type&;
+ using const_reference = const value_type&;
+ using size_type = typename __alloc_traits::size_type;
+ using difference_type = typename __alloc_traits::difference_type;
+ using pointer = typename __alloc_traits::pointer;
+ using const_pointer = typename __alloc_traits::const_pointer;
+ using iterator = pointer;
+ using const_iterator = const_pointer;
+
+ // A __split_buffer contains the following members which may be trivially relocatable:
+ // - pointer: may be trivially relocatable, so it's checked
+ // - allocator_type: may be trivially relocatable, so it's checked
+ // __split_buffer doesn't have any self-references, so it's trivially relocatable if its members are.
+ using __trivially_relocatable = __conditional_t<
+ __libcpp_is_trivially_relocatable<pointer>::value && __libcpp_is_trivially_relocatable<allocator_type>::value,
+ __split_buffer,
+ void>;
+
+ pointer __first_;
+ pointer __begin_;
+ pointer __end_;
+ __compressed_pair<pointer, allocator_type> __end_cap_;
+
+ using __alloc_ref = __add_lvalue_reference_t<allocator_type>;
+ using __alloc_const_ref = __add_lvalue_reference_t<allocator_type>;
+
+ __split_buffer(const __split_buffer&) = delete;
+ __split_buffer& operator=(const __split_buffer&) = delete;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer()
+ _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
+ : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __default_init_tag()) {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit __split_buffer(__alloc_rr& __a)
+ : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a) {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit __split_buffer(const __alloc_rr& __a)
+ : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a) {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+ __split_buffer(size_type __cap, size_type __start, __alloc_rr& __a);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c)
+ _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c, const __alloc_rr& __a);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer& operator=(__split_buffer&& __c)
+ _NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value) ||
+ !__alloc_traits::propagate_on_container_move_assignment::value);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~__split_buffer();
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __alloc_rr& __alloc() _NOEXCEPT { return __end_cap_.second(); }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const __alloc_rr& __alloc() const _NOEXCEPT {
+ return __end_cap_.second();
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pointer& __end_cap() _NOEXCEPT { return __end_cap_.first(); }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const pointer& __end_cap() const _NOEXCEPT {
+ return __end_cap_.first();
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __begin_; }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __begin_; }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __end_; }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __end_; }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __destruct_at_end(__begin_); }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type size() const {
+ return static_cast<size_type>(__end_ - __begin_);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool empty() const { return __end_ == __begin_; }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type capacity() const {
+ return static_cast<size_type>(__end_cap() - __first_);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type __front_spare() const {
+ return static_cast<size_type>(__begin_ - __first_);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type __back_spare() const {
+ return static_cast<size_type>(__end_cap() - __end_);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference front() { return *__begin_; }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference front() const { return *__begin_; }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference back() { return *(__end_ - 1); }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference back() const { return *(__end_ - 1); }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void shrink_to_fit() _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_front(const_reference __x);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(const_reference __x);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_front(value_type&& __x);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(value_type&& __x);
+
+ template <class... _Args>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void emplace_back(_Args&&... __args);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void pop_front() { __destruct_at_begin(__begin_ + 1); }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void pop_back() { __destruct_at_end(__end_ - 1); }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n, const_reference __x);
+
+ template <class _InputIter, __enable_if_t<__has_exactly_input_iterator_category<_InputIter>::value, int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(_InputIter __first, _InputIter __last);
+
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __construct_at_end(_ForwardIterator __first, _ForwardIterator __last);
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __construct_at_end_with_sentinel(_Iterator __first, _Sentinel __last);
+
+ template <class _Iterator>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __construct_at_end_with_size(_Iterator __first, size_type __n);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin) {
+ __destruct_at_begin(__new_begin, is_trivially_destructible<value_type>());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin, false_type);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin, true_type);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last) _NOEXCEPT {
+ __destruct_at_end(__new_last, false_type());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last, false_type) _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last, true_type) _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void swap(__split_buffer& __x)
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__alloc_rr>);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __invariants() const;
+
+private:
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__split_buffer& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
+ __alloc() = std::move(__c.__alloc());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__split_buffer&, false_type) _NOEXCEPT {}
+
+ struct _ConstructTransaction {
+ _LIBCPP_CONSTEXPR_SINCE_CXX20
+ _LIBCPP_HIDE_FROM_ABI explicit _ConstructTransaction(pointer* __p, size_type __n) _NOEXCEPT
+ : __pos_(*__p),
+ __end_(*__p + __n),
+ __dest_(__p) {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~_ConstructTransaction() { *__dest_ = __pos_; }
+
+ pointer __pos_;
+ const pointer __end_;
+
+ private:
+ pointer* __dest_;
+ };
+};
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 bool __split_buffer<_Tp, _Allocator>::__invariants() const {
+ if (__first_ == nullptr) {
+ if (__begin_ != nullptr)
+ return false;
+ if (__end_ != nullptr)
+ return false;
+ if (__end_cap() != nullptr)
+ return false;
+ } else {
+ if (__begin_ < __first_)
+ return false;
+ if (__end_ < __begin_)
+ return false;
+ if (__end_cap() < __end_)
+ return false;
+ }
+ return true;
+}
+
+// Default constructs __n objects starting at __end_
+// throws if construction throws
+// Precondition: __n > 0
+// Precondition: size() + __n <= capacity()
+// Postcondition: size() == size() + __n
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::__construct_at_end(size_type __n) {
+ _ConstructTransaction __tx(&this->__end_, __n);
+ for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
+ __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_));
+ }
+}
+
+// Copy constructs __n objects starting at __end_ from __x
+// throws if construction throws
+// Precondition: __n > 0
+// Precondition: size() + __n <= capacity()
+// Postcondition: size() == old size() + __n
+// Postcondition: [i] == __x for all i in [size() - __n, __n)
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__split_buffer<_Tp, _Allocator>::__construct_at_end(size_type __n, const_reference __x) {
+ _ConstructTransaction __tx(&this->__end_, __n);
+ for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
+ __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_), __x);
+ }
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIter, __enable_if_t<__has_exactly_input_iterator_category<_InputIter>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__split_buffer<_Tp, _Allocator>::__construct_at_end(_InputIter __first, _InputIter __last) {
+ __construct_at_end_with_sentinel(__first, __last);
+}
+
+template <class _Tp, class _Allocator>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__split_buffer<_Tp, _Allocator>::__construct_at_end_with_sentinel(_Iterator __first, _Sentinel __last) {
+ __alloc_rr& __a = this->__alloc();
+ for (; __first != __last; ++__first) {
+ if (__end_ == __end_cap()) {
+ size_type __old_cap = __end_cap() - __first_;
+ size_type __new_cap = std::max<size_type>(2 * __old_cap, 8);
+ __split_buffer __buf(__new_cap, 0, __a);
+ for (pointer __p = __begin_; __p != __end_; ++__p, (void)++__buf.__end_)
+ __alloc_traits::construct(__buf.__alloc(), std::__to_address(__buf.__end_), std::move(*__p));
+ swap(__buf);
+ }
+ __alloc_traits::construct(__a, std::__to_address(this->__end_), *__first);
+ ++this->__end_;
+ }
+}
+template <class _Tp, class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__split_buffer<_Tp, _Allocator>::__construct_at_end(_ForwardIterator __first, _ForwardIterator __last) {
+ __construct_at_end_with_size(__first, std::distance(__first, __last));
+}
+
+template <class _Tp, class _Allocator>
+template <class _ForwardIterator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+__split_buffer<_Tp, _Allocator>::__construct_at_end_with_size(_ForwardIterator __first, size_type __n) {
+ _ConstructTransaction __tx(&this->__end_, __n);
+ for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_, (void)++__first) {
+ __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_), *__first);
+ }
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline void
+__split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, false_type) {
+ while (__begin_ != __new_begin)
+ __alloc_traits::destroy(__alloc(), std::__to_address(__begin_++));
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline void
+__split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, true_type) {
+ __begin_ = __new_begin;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
+__split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, false_type) _NOEXCEPT {
+ while (__new_last != __end_)
+ __alloc_traits::destroy(__alloc(), std::__to_address(--__end_));
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
+__split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, true_type) _NOEXCEPT {
+ __end_ = __new_last;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+__split_buffer<_Tp, _Allocator>::__split_buffer(size_type __cap, size_type __start, __alloc_rr& __a)
+ : __end_cap_(nullptr, __a) {
+ if (__cap == 0) {
+ __first_ = nullptr;
+ } else {
+ auto __allocation = std::__allocate_at_least(__alloc(), __cap);
+ __first_ = __allocation.ptr;
+ __cap = __allocation.count;
+ }
+ __begin_ = __end_ = __first_ + __start;
+ __end_cap() = __first_ + __cap;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator>::~__split_buffer() {
+ clear();
+ if (__first_)
+ __alloc_traits::deallocate(__alloc(), __first_, capacity());
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator>::__split_buffer(__split_buffer&& __c)
+ _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
+ : __first_(std::move(__c.__first_)),
+ __begin_(std::move(__c.__begin_)),
+ __end_(std::move(__c.__end_)),
+ __end_cap_(std::move(__c.__end_cap_)) {
+ __c.__first_ = nullptr;
+ __c.__begin_ = nullptr;
+ __c.__end_ = nullptr;
+ __c.__end_cap() = nullptr;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+__split_buffer<_Tp, _Allocator>::__split_buffer(__split_buffer&& __c, const __alloc_rr& __a)
+ : __end_cap_(nullptr, __a) {
+ if (__a == __c.__alloc()) {
+ __first_ = __c.__first_;
+ __begin_ = __c.__begin_;
+ __end_ = __c.__end_;
+ __end_cap() = __c.__end_cap();
+ __c.__first_ = nullptr;
+ __c.__begin_ = nullptr;
+ __c.__end_ = nullptr;
+ __c.__end_cap() = nullptr;
+ } else {
+ auto __allocation = std::__allocate_at_least(__alloc(), __c.size());
+ __first_ = __allocation.ptr;
+ __begin_ = __end_ = __first_;
+ __end_cap() = __first_ + __allocation.count;
+ typedef move_iterator<iterator> _Ip;
+ __construct_at_end(_Ip(__c.begin()), _Ip(__c.end()));
+ }
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator>&
+__split_buffer<_Tp, _Allocator>::operator=(__split_buffer&& __c)
+ _NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value) ||
+ !__alloc_traits::propagate_on_container_move_assignment::value) {
+ clear();
+ shrink_to_fit();
+ __first_ = __c.__first_;
+ __begin_ = __c.__begin_;
+ __end_ = __c.__end_;
+ __end_cap() = __c.__end_cap();
+ __move_assign_alloc(__c, integral_constant<bool, __alloc_traits::propagate_on_container_move_assignment::value>());
+ __c.__first_ = __c.__begin_ = __c.__end_ = __c.__end_cap() = nullptr;
+ return *this;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::swap(__split_buffer& __x)
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__alloc_rr>) {
+ std::swap(__first_, __x.__first_);
+ std::swap(__begin_, __x.__begin_);
+ std::swap(__end_, __x.__end_);
+ std::swap(__end_cap(), __x.__end_cap());
+ std::__swap_allocator(__alloc(), __x.__alloc());
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::reserve(size_type __n) {
+ if (__n < capacity()) {
+ __split_buffer<value_type, __alloc_rr&> __t(__n, 0, __alloc());
+ __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
+ std::swap(__first_, __t.__first_);
+ std::swap(__begin_, __t.__begin_);
+ std::swap(__end_, __t.__end_);
+ std::swap(__end_cap(), __t.__end_cap());
+ }
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT {
+ if (capacity() > size()) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __split_buffer<value_type, __alloc_rr&> __t(size(), 0, __alloc());
+ __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
+ __t.__end_ = __t.__begin_ + (__end_ - __begin_);
+ std::swap(__first_, __t.__first_);
+ std::swap(__begin_, __t.__begin_);
+ std::swap(__end_, __t.__end_);
+ std::swap(__end_cap(), __t.__end_cap());
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::push_front(const_reference __x) {
+ if (__begin_ == __first_) {
+ if (__end_ < __end_cap()) {
+ difference_type __d = __end_cap() - __end_;
+ __d = (__d + 1) / 2;
+ __begin_ = std::move_backward(__begin_, __end_, __end_ + __d);
+ __end_ += __d;
+ } else {
+ size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
+ __split_buffer<value_type, __alloc_rr&> __t(__c, (__c + 3) / 4, __alloc());
+ __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
+ std::swap(__first_, __t.__first_);
+ std::swap(__begin_, __t.__begin_);
+ std::swap(__end_, __t.__end_);
+ std::swap(__end_cap(), __t.__end_cap());
+ }
+ }
+ __alloc_traits::construct(__alloc(), std::__to_address(__begin_ - 1), __x);
+ --__begin_;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::push_front(value_type&& __x) {
+ if (__begin_ == __first_) {
+ if (__end_ < __end_cap()) {
+ difference_type __d = __end_cap() - __end_;
+ __d = (__d + 1) / 2;
+ __begin_ = std::move_backward(__begin_, __end_, __end_ + __d);
+ __end_ += __d;
+ } else {
+ size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
+ __split_buffer<value_type, __alloc_rr&> __t(__c, (__c + 3) / 4, __alloc());
+ __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
+ std::swap(__first_, __t.__first_);
+ std::swap(__begin_, __t.__begin_);
+ std::swap(__end_, __t.__end_);
+ std::swap(__end_cap(), __t.__end_cap());
+ }
+ }
+ __alloc_traits::construct(__alloc(), std::__to_address(__begin_ - 1), std::move(__x));
+ --__begin_;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
+__split_buffer<_Tp, _Allocator>::push_back(const_reference __x) {
+ if (__end_ == __end_cap()) {
+ if (__begin_ > __first_) {
+ difference_type __d = __begin_ - __first_;
+ __d = (__d + 1) / 2;
+ __end_ = std::move(__begin_, __end_, __begin_ - __d);
+ __begin_ -= __d;
+ } else {
+ size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
+ __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
+ __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
+ std::swap(__first_, __t.__first_);
+ std::swap(__begin_, __t.__begin_);
+ std::swap(__end_, __t.__end_);
+ std::swap(__end_cap(), __t.__end_cap());
+ }
+ }
+ __alloc_traits::construct(__alloc(), std::__to_address(__end_), __x);
+ ++__end_;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::push_back(value_type&& __x) {
+ if (__end_ == __end_cap()) {
+ if (__begin_ > __first_) {
+ difference_type __d = __begin_ - __first_;
+ __d = (__d + 1) / 2;
+ __end_ = std::move(__begin_, __end_, __begin_ - __d);
+ __begin_ -= __d;
+ } else {
+ size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
+ __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
+ __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
+ std::swap(__first_, __t.__first_);
+ std::swap(__begin_, __t.__begin_);
+ std::swap(__end_, __t.__end_);
+ std::swap(__end_cap(), __t.__end_cap());
+ }
+ }
+ __alloc_traits::construct(__alloc(), std::__to_address(__end_), std::move(__x));
+ ++__end_;
+}
+
+template <class _Tp, class _Allocator>
+template <class... _Args>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::emplace_back(_Args&&... __args) {
+ if (__end_ == __end_cap()) {
+ if (__begin_ > __first_) {
+ difference_type __d = __begin_ - __first_;
+ __d = (__d + 1) / 2;
+ __end_ = std::move(__begin_, __end_, __begin_ - __d);
+ __begin_ -= __d;
+ } else {
+ size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
+ __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
+ __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
+ std::swap(__first_, __t.__first_);
+ std::swap(__begin_, __t.__begin_);
+ std::swap(__end_, __t.__end_);
+ std::swap(__end_cap(), __t.__end_cap());
+ }
+ }
+ __alloc_traits::construct(__alloc(), std::__to_address(__end_), std::forward<_Args>(__args)...);
+ ++__end_;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
+swap(__split_buffer<_Tp, _Allocator>& __x, __split_buffer<_Tp, _Allocator>& __y) _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___SPLIT_BUFFER
diff --git a/libcxx/include/__cxx03/__std_clang_module b/libcxx/include/__cxx03/__std_clang_module
new file mode 100644
index 00000000000000..18d6ce6b46c1f6
--- /dev/null
+++ b/libcxx/include/__cxx03/__std_clang_module
@@ -0,0 +1,215 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// WARNING, this entire header is generated by
+// utils/generate_std_clang_module_header.py
+// DO NOT MODIFY!
+
+// This header should not be directly included, it's exclusively to import all
+// of the libc++ public clang modules for the `std` clang module to export. In
+// other words, it's to facilitate `@import std;` in Objective-C++ and `import std`
+// in Swift to expose all of the libc++ interfaces. This is generally not
+// recommended, however there are some clients that need to import all of libc++
+// without knowing what "all" is.
+#if !__building_module(std)
+# error "Do not include this header directly, include individual headers instead"
+#endif
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#include <algorithm>
+#include <any>
+#include <array>
+#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
+# include <atomic>
+#endif
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+# include <barrier>
+#endif
+#include <bit>
+#include <bitset>
+#include <cassert>
+#include <ccomplex>
+#include <cctype>
+#include <cerrno>
+#include <cfenv>
+#include <cfloat>
+#include <charconv>
+#include <chrono>
+#include <cinttypes>
+#include <ciso646>
+#include <climits>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <clocale>
+#endif
+#include <cmath>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <codecvt>
+#endif
+#include <compare>
+#include <complex.h>
+#include <complex>
+#include <concepts>
+#include <condition_variable>
+#include <coroutine>
+#include <csetjmp>
+#include <csignal>
+#include <cstdarg>
+#include <cstdbool>
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <ctgmath>
+#include <ctime>
+#include <ctype.h>
+#include <cuchar>
+#if !defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+# include <cwchar>
+#endif
+#if !defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+# include <cwctype>
+#endif
+#include <deque>
+#include <errno.h>
+#include <exception>
+#include <execution>
+#include <expected>
+#include <experimental/iterator>
+#include <experimental/memory>
+#include <experimental/propagate_const>
+#include <experimental/simd>
+#include <experimental/type_traits>
+#include <experimental/utility>
+#include <fenv.h>
+#include <filesystem>
+#include <float.h>
+#include <format>
+#include <forward_list>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <fstream>
+#endif
+#include <functional>
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+# include <future>
+#endif
+#include <initializer_list>
+#include <inttypes.h>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <iomanip>
+#endif
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <ios>
+#endif
+#include <iosfwd>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <iostream>
+#endif
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <istream>
+#endif
+#include <iterator>
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+# include <latch>
+#endif
+#include <limits>
+#include <list>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <locale.h>
+#endif
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <locale>
+#endif
+#include <map>
+#include <math.h>
+#include <mdspan>
+#include <memory>
+#include <memory_resource>
+#include <mutex>
+#include <new>
+#include <numbers>
+#include <numeric>
+#include <optional>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <ostream>
+#endif
+#include <print>
+#include <queue>
+#include <random>
+#include <ranges>
+#include <ratio>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <regex>
+#endif
+#include <scoped_allocator>
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+# include <semaphore>
+#endif
+#include <set>
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+# include <shared_mutex>
+#endif
+#include <source_location>
+#include <span>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <sstream>
+#endif
+#include <stack>
+#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
+# include <stdatomic.h>
+#endif
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdexcept>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+# include <stop_token>
+#endif
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <streambuf>
+#endif
+#include <string.h>
+#include <string>
+#include <string_view>
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <strstream>
+#endif
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <syncstream>
+#endif
+#include <system_error>
+#include <tgmath.h>
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+# include <thread>
+#endif
+#include <tuple>
+#include <type_traits>
+#include <typeindex>
+#include <typeinfo>
+#include <uchar.h>
+#include <unordered_map>
+#include <unordered_set>
+#include <utility>
+#include <valarray>
+#include <variant>
+#include <vector>
+#include <version>
+#if !defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+# include <wchar.h>
+#endif
+#if !defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+# include <wctype.h>
+#endif
diff --git a/libcxx/include/__cxx03/__std_mbstate_t.h b/libcxx/include/__cxx03/__std_mbstate_t.h
new file mode 100644
index 00000000000000..e79cc789fddf9b
--- /dev/null
+++ b/libcxx/include/__cxx03/__std_mbstate_t.h
@@ -0,0 +1,29 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STD_MBSTATE_T_H
+#define _LIBCPP___STD_MBSTATE_T_H
+
+#include <__config>
+#include <__mbstate_t.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// The goal of this header is to provide std::mbstate_t without requiring all
+// of <cuchar> or <cwchar>.
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::mbstate_t _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___STD_MBSTATE_T_H
diff --git a/libcxx/include/__cxx03/__stop_token/atomic_unique_lock.h b/libcxx/include/__cxx03/__stop_token/atomic_unique_lock.h
new file mode 100644
index 00000000000000..13e59f9f0dce00
--- /dev/null
+++ b/libcxx/include/__cxx03/__stop_token/atomic_unique_lock.h
@@ -0,0 +1,140 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STOP_TOKEN_ATOMIC_UNIQUE_GUARD_H
+#define _LIBCPP___STOP_TOKEN_ATOMIC_UNIQUE_GUARD_H
+
+#include <__bit/popcount.h>
+#include <__config>
+#include <atomic>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// This class implements an RAII unique_lock without a mutex.
+// It uses std::atomic<State>,
+// where State contains a lock bit and might contain other data,
+// and LockedBit is the value of State when the lock bit is set, e.g 1 << 2
+template <class _State, _State _LockedBit>
+class _LIBCPP_AVAILABILITY_SYNC __atomic_unique_lock {
+ static_assert(std::__libcpp_popcount(static_cast<unsigned long long>(_LockedBit)) == 1,
+ "LockedBit must be an integer where only one bit is set");
+
+ std::atomic<_State>& __state_;
+ bool __is_locked_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __atomic_unique_lock(std::atomic<_State>& __state) noexcept
+ : __state_(__state), __is_locked_(true) {
+ __lock();
+ }
+
+ template <class _Pred>
+ _LIBCPP_HIDE_FROM_ABI __atomic_unique_lock(std::atomic<_State>& __state, _Pred&& __give_up_locking) noexcept
+ : __state_(__state), __is_locked_(false) {
+ __is_locked_ = __lock_impl(__give_up_locking, __set_locked_bit, std::memory_order_acquire);
+ }
+
+ template <class _Pred, class _UnaryFunction>
+ _LIBCPP_HIDE_FROM_ABI __atomic_unique_lock(
+ std::atomic<_State>& __state,
+ _Pred&& __give_up_locking,
+ _UnaryFunction&& __state_after_lock,
+ std::memory_order __locked_ordering) noexcept
+ : __state_(__state), __is_locked_(false) {
+ __is_locked_ = __lock_impl(__give_up_locking, __state_after_lock, __locked_ordering);
+ }
+
+ __atomic_unique_lock(const __atomic_unique_lock&) = delete;
+ __atomic_unique_lock(__atomic_unique_lock&&) = delete;
+ __atomic_unique_lock& operator=(const __atomic_unique_lock&) = delete;
+ __atomic_unique_lock& operator=(__atomic_unique_lock&&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI ~__atomic_unique_lock() {
+ if (__is_locked_) {
+ __unlock();
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool __owns_lock() const noexcept { return __is_locked_; }
+
+ _LIBCPP_HIDE_FROM_ABI void __lock() noexcept {
+ const auto __never_give_up_locking = [](_State) { return false; };
+ // std::memory_order_acquire because we'd like to make sure that all the read operations after the lock can read the
+ // up-to-date values.
+ __lock_impl(__never_give_up_locking, __set_locked_bit, std::memory_order_acquire);
+ __is_locked_ = true;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __unlock() noexcept {
+ // unset the _LockedBit. `memory_order_release` because we need to make sure all the write operations before calling
+ // `__unlock` will be made visible to other threads
+ __state_.fetch_and(static_cast<_State>(~_LockedBit), std::memory_order_release);
+ __state_.notify_all();
+ __is_locked_ = false;
+ }
+
+private:
+ template <class _Pred, class _UnaryFunction>
+ _LIBCPP_HIDE_FROM_ABI bool
+ __lock_impl(_Pred&& __give_up_locking, // while trying to lock the state, if the predicate returns true, give up
+ // locking and return
+ _UnaryFunction&& __state_after_lock,
+ std::memory_order __locked_ordering) noexcept {
+ // At this stage, until we exit the inner while loop, other than the atomic state, we are not reading any order
+ // dependent values that is written on other threads, or writing anything that needs to be seen on other threads.
+ // Therefore `memory_order_relaxed` is enough.
+ _State __current_state = __state_.load(std::memory_order_relaxed);
+ do {
+ while (true) {
+ if (__give_up_locking(__current_state)) {
+ // user provided early return condition. fail to lock
+ return false;
+ } else if ((__current_state & _LockedBit) != 0) {
+ // another thread has locked the state, we need to wait
+ __state_.wait(__current_state, std::memory_order_relaxed);
+ // when it is woken up by notifyAll or spuriously, the __state_
+ // might have changed. reload the state
+ // Note that the new state's _LockedBit may or may not equal to 0
+ __current_state = __state_.load(std::memory_order_relaxed);
+ } else {
+ // at least for now, it is not locked. we can try `compare_exchange_weak` to lock it.
+ // Note that the variable `__current_state`'s lock bit has to be 0 at this point.
+ break;
+ }
+ }
+ } while (!__state_.compare_exchange_weak(
+ __current_state, // if __state_ has the same value of __current_state, lock bit must be zero before exchange and
+ // we are good to lock/exchange and return. If _state has a different value, because other
+ // threads locked it between the `break` statement above and this statement, exchange will fail
+ // and go back to the inner while loop above.
+ __state_after_lock(__current_state), // state after lock. Usually it should be __current_state | _LockedBit.
+ // Some use cases need to set other bits at the same time as an atomic
+ // operation therefore we accept a function
+ __locked_ordering, // sucessful exchange order. Usually it should be std::memory_order_acquire.
+ // Some use cases need more strict ordering therefore we accept it as a parameter
+ std::memory_order_relaxed // fail to exchange order. We don't need any ordering as we are going back to the
+ // inner while loop
+ ));
+ return true;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __set_locked_bit = [](_State __state) { return __state | _LockedBit; };
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___STOP_TOKEN_ATOMIC_UNIQUE_GUARD_H
diff --git a/libcxx/include/__cxx03/__stop_token/intrusive_list_view.h b/libcxx/include/__cxx03/__stop_token/intrusive_list_view.h
new file mode 100644
index 00000000000000..11a3e267e7c6d6
--- /dev/null
+++ b/libcxx/include/__cxx03/__stop_token/intrusive_list_view.h
@@ -0,0 +1,85 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STOP_TOKEN_INTRUSIVE_LIST_VIEW_H
+#define _LIBCPP___STOP_TOKEN_INTRUSIVE_LIST_VIEW_H
+
+#include <__assert>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Derived>
+struct __intrusive_node_base {
+ _Derived* __next_ = nullptr;
+ _Derived* __prev_ = nullptr;
+};
+
+// This class is a view of underlying double-linked list.
+// It does not own the nodes. It provides user-friendly
+// operations on the linked list.
+template <class _Node>
+struct __intrusive_list_view {
+ _LIBCPP_HIDE_FROM_ABI __intrusive_list_view() = default;
+ _LIBCPP_HIDE_FROM_ABI __intrusive_list_view(__intrusive_list_view const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __intrusive_list_view(__intrusive_list_view&&) = default;
+ _LIBCPP_HIDE_FROM_ABI __intrusive_list_view& operator=(__intrusive_list_view const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __intrusive_list_view& operator=(__intrusive_list_view&&) = default;
+ _LIBCPP_HIDE_FROM_ABI ~__intrusive_list_view() = default;
+
+ _LIBCPP_HIDE_FROM_ABI bool __empty() const noexcept { return __head_ == nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void __push_front(_Node* __node) noexcept {
+ __node->__next_ = __head_;
+ if (__head_) {
+ __head_->__prev_ = __node;
+ }
+ __head_ = __node;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Node* __pop_front() noexcept {
+ _Node* __front = __head_;
+ __head_ = __head_->__next_;
+ if (__head_) {
+ __head_->__prev_ = nullptr;
+ }
+ // OK not to set __front->__next_ = nullptr as __front is not part of the list anymore
+ return __front;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __remove(_Node* __node) noexcept {
+ if (__node->__prev_) {
+ // prev exists, set its next to our next to skip __node
+ __node->__prev_->__next_ = __node->__next_;
+ if (__node->__next_) {
+ __node->__next_->__prev_ = __node->__prev_;
+ }
+ } else {
+ _LIBCPP_ASSERT_INTERNAL(__node == __head_, "Node to be removed has no prev node, so it has to be the head");
+ __pop_front();
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool __is_head(_Node* __node) noexcept { return __node == __head_; }
+
+private:
+ _Node* __head_ = nullptr;
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___STOP_TOKEN_INTRUSIVE_LIST_VIEW_H
diff --git a/libcxx/include/__cxx03/__stop_token/intrusive_shared_ptr.h b/libcxx/include/__cxx03/__stop_token/intrusive_shared_ptr.h
new file mode 100644
index 00000000000000..f00cea5bc2b670
--- /dev/null
+++ b/libcxx/include/__cxx03/__stop_token/intrusive_shared_ptr.h
@@ -0,0 +1,134 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STOP_TOKEN_INTRUSIVE_SHARED_PTR_H
+#define _LIBCPP___STOP_TOKEN_INTRUSIVE_SHARED_PTR_H
+
+#include <__atomic/atomic.h>
+#include <__atomic/memory_order.h>
+#include <__config>
+#include <__type_traits/is_reference.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+// For intrusive_shared_ptr to work with a type T, specialize __intrusive_shared_ptr_traits<T> and implement
+// the following function:
+//
+// static std::atomic<U>& __get_atomic_ref_count(T&);
+//
+// where U must be an integral type representing the number of references to the object.
+template <class _Tp>
+struct __intrusive_shared_ptr_traits;
+
+// A reference counting shared_ptr for types whose reference counter
+// is stored inside the class _Tp itself.
+// When the reference count goes to zero, the destructor of _Tp will be called
+template <class _Tp>
+struct __intrusive_shared_ptr {
+ _LIBCPP_HIDE_FROM_ABI __intrusive_shared_ptr() = default;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __intrusive_shared_ptr(_Tp* __raw_ptr) : __raw_ptr_(__raw_ptr) {
+ if (__raw_ptr_)
+ __increment_ref_count(*__raw_ptr_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __intrusive_shared_ptr(const __intrusive_shared_ptr& __other) noexcept
+ : __raw_ptr_(__other.__raw_ptr_) {
+ if (__raw_ptr_)
+ __increment_ref_count(*__raw_ptr_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __intrusive_shared_ptr(__intrusive_shared_ptr&& __other) noexcept
+ : __raw_ptr_(__other.__raw_ptr_) {
+ __other.__raw_ptr_ = nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __intrusive_shared_ptr& operator=(const __intrusive_shared_ptr& __other) noexcept {
+ if (__other.__raw_ptr_ != __raw_ptr_) {
+ if (__other.__raw_ptr_) {
+ __increment_ref_count(*__other.__raw_ptr_);
+ }
+ if (__raw_ptr_) {
+ __decrement_ref_count(*__raw_ptr_);
+ }
+ __raw_ptr_ = __other.__raw_ptr_;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __intrusive_shared_ptr& operator=(__intrusive_shared_ptr&& __other) noexcept {
+ __intrusive_shared_ptr(std::move(__other)).swap(*this);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~__intrusive_shared_ptr() {
+ if (__raw_ptr_) {
+ __decrement_ref_count(*__raw_ptr_);
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp* operator->() const noexcept { return __raw_ptr_; }
+ _LIBCPP_HIDE_FROM_ABI _Tp& operator*() const noexcept { return *__raw_ptr_; }
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const noexcept { return __raw_ptr_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(__intrusive_shared_ptr& __other) { std::swap(__raw_ptr_, __other.__raw_ptr_); }
+
+ _LIBCPP_HIDE_FROM_ABI friend void swap(__intrusive_shared_ptr& __lhs, __intrusive_shared_ptr& __rhs) {
+ __lhs.swap(__rhs);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool constexpr
+ operator==(const __intrusive_shared_ptr&, const __intrusive_shared_ptr&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI friend bool constexpr operator==(const __intrusive_shared_ptr& __ptr, std::nullptr_t) {
+ return __ptr.__raw_ptr_ == nullptr;
+ }
+
+private:
+ _Tp* __raw_ptr_ = nullptr;
+
+ // the memory order for increment/decrement the counter is the same for shared_ptr
+ // increment is relaxed and decrement is acq_rel
+ _LIBCPP_HIDE_FROM_ABI static void __increment_ref_count(_Tp& __obj) {
+ __get_atomic_ref_count(__obj).fetch_add(1, std::memory_order_relaxed);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void __decrement_ref_count(_Tp& __obj) {
+ if (__get_atomic_ref_count(__obj).fetch_sub(1, std::memory_order_acq_rel) == 1) {
+ delete &__obj;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static decltype(auto) __get_atomic_ref_count(_Tp& __obj) {
+ using __ret_type = decltype(__intrusive_shared_ptr_traits<_Tp>::__get_atomic_ref_count(__obj));
+ static_assert(
+ std::is_reference_v<__ret_type>, "__get_atomic_ref_count should return a reference to the atomic counter");
+ return __intrusive_shared_ptr_traits<_Tp>::__get_atomic_ref_count(__obj);
+ }
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___STOP_TOKEN_INTRUSIVE_SHARED_PTR_H
diff --git a/libcxx/include/__cxx03/__stop_token/stop_callback.h b/libcxx/include/__cxx03/__stop_token/stop_callback.h
new file mode 100644
index 00000000000000..760cf2bb55b0ce
--- /dev/null
+++ b/libcxx/include/__cxx03/__stop_token/stop_callback.h
@@ -0,0 +1,102 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STOP_TOKEN_STOP_CALLBACK_H
+#define _LIBCPP___STOP_TOKEN_STOP_CALLBACK_H
+
+#include <__concepts/constructible.h>
+#include <__concepts/destructible.h>
+#include <__concepts/invocable.h>
+#include <__config>
+#include <__stop_token/intrusive_shared_ptr.h>
+#include <__stop_token/stop_state.h>
+#include <__stop_token/stop_token.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/private_constructor_tag.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
+
+template <class _Callback>
+class _LIBCPP_AVAILABILITY_SYNC stop_callback : private __stop_callback_base {
+ static_assert(invocable<_Callback>,
+ "Mandates: stop_callback is instantiated with an argument for the template parameter Callback that "
+ "satisfies invocable.");
+ static_assert(destructible<_Callback>,
+ "Mandates: stop_callback is instantiated with an argument for the template parameter Callback that "
+ "satisfies destructible.");
+
+public:
+ using callback_type = _Callback;
+
+ template <class _Cb>
+ requires constructible_from<_Callback, _Cb>
+ _LIBCPP_HIDE_FROM_ABI explicit stop_callback(const stop_token& __st,
+ _Cb&& __cb) noexcept(is_nothrow_constructible_v<_Callback, _Cb>)
+ : stop_callback(__private_constructor_tag{}, __st.__state_, std::forward<_Cb>(__cb)) {}
+
+ template <class _Cb>
+ requires constructible_from<_Callback, _Cb>
+ _LIBCPP_HIDE_FROM_ABI explicit stop_callback(stop_token&& __st,
+ _Cb&& __cb) noexcept(is_nothrow_constructible_v<_Callback, _Cb>)
+ : stop_callback(__private_constructor_tag{}, std::move(__st.__state_), std::forward<_Cb>(__cb)) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~stop_callback() {
+ if (__state_) {
+ __state_->__remove_callback(this);
+ }
+ }
+
+ stop_callback(const stop_callback&) = delete;
+ stop_callback(stop_callback&&) = delete;
+ stop_callback& operator=(const stop_callback&) = delete;
+ stop_callback& operator=(stop_callback&&) = delete;
+
+private:
+ _LIBCPP_NO_UNIQUE_ADDRESS _Callback __callback_;
+ __intrusive_shared_ptr<__stop_state> __state_;
+
+ friend __stop_callback_base;
+
+ template <class _StatePtr, class _Cb>
+ _LIBCPP_HIDE_FROM_ABI explicit stop_callback(__private_constructor_tag, _StatePtr&& __state, _Cb&& __cb) noexcept(
+ is_nothrow_constructible_v<_Callback, _Cb>)
+ : __stop_callback_base([](__stop_callback_base* __cb_base) noexcept {
+ // stop callback is supposed to only be called once
+ std::forward<_Callback>(static_cast<stop_callback*>(__cb_base)->__callback_)();
+ }),
+ __callback_(std::forward<_Cb>(__cb)),
+ __state_() {
+ if (__state && __state->__add_callback(this)) {
+ // st.stop_requested() was false and this is successfully added to the linked list
+ __state_ = std::forward<_StatePtr>(__state);
+ }
+ }
+};
+
+template <class _Callback>
+_LIBCPP_AVAILABILITY_SYNC stop_callback(stop_token, _Callback) -> stop_callback<_Callback>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
diff --git a/libcxx/include/__cxx03/__stop_token/stop_source.h b/libcxx/include/__cxx03/__stop_token/stop_source.h
new file mode 100644
index 00000000000000..70697462784ab4
--- /dev/null
+++ b/libcxx/include/__cxx03/__stop_token/stop_source.h
@@ -0,0 +1,91 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STOP_TOKEN_STOP_SOURCE_H
+#define _LIBCPP___STOP_TOKEN_STOP_SOURCE_H
+
+#include <__config>
+#include <__stop_token/intrusive_shared_ptr.h>
+#include <__stop_token/stop_state.h>
+#include <__stop_token/stop_token.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
+
+struct nostopstate_t {
+ explicit nostopstate_t() = default;
+};
+
+inline constexpr nostopstate_t nostopstate{};
+
+class _LIBCPP_AVAILABILITY_SYNC stop_source {
+public:
+ _LIBCPP_HIDE_FROM_ABI stop_source() : __state_(new __stop_state()) { __state_->__increment_stop_source_counter(); }
+
+ _LIBCPP_HIDE_FROM_ABI explicit stop_source(nostopstate_t) noexcept : __state_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI stop_source(const stop_source& __other) noexcept : __state_(__other.__state_) {
+ if (__state_) {
+ __state_->__increment_stop_source_counter();
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI stop_source(stop_source&& __other) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI stop_source& operator=(const stop_source& __other) noexcept {
+ // increment `__other` first so that we don't hit 0 in case of self-assignment
+ if (__other.__state_) {
+ __other.__state_->__increment_stop_source_counter();
+ }
+ if (__state_) {
+ __state_->__decrement_stop_source_counter();
+ }
+ __state_ = __other.__state_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI stop_source& operator=(stop_source&&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI ~stop_source() {
+ if (__state_) {
+ __state_->__decrement_stop_source_counter();
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(stop_source& __other) noexcept { __state_.swap(__other.__state_); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI stop_token get_token() const noexcept { return stop_token(__state_); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_possible() const noexcept { return __state_ != nullptr; }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_requested() const noexcept {
+ return __state_ != nullptr && __state_->__stop_requested();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool request_stop() noexcept { return __state_ && __state_->__request_stop(); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI friend bool operator==(const stop_source&, const stop_source&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI friend void swap(stop_source& __lhs, stop_source& __rhs) noexcept { __lhs.swap(__rhs); }
+
+private:
+ __intrusive_shared_ptr<__stop_state> __state_;
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
diff --git a/libcxx/include/__cxx03/__stop_token/stop_state.h b/libcxx/include/__cxx03/__stop_token/stop_state.h
new file mode 100644
index 00000000000000..b0eed13a143cfc
--- /dev/null
+++ b/libcxx/include/__cxx03/__stop_token/stop_state.h
@@ -0,0 +1,236 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STOP_TOKEN_STOP_STATE_H
+#define _LIBCPP___STOP_TOKEN_STOP_STATE_H
+
+#include <__assert>
+#include <__config>
+#include <__stop_token/atomic_unique_lock.h>
+#include <__stop_token/intrusive_list_view.h>
+#include <__thread/id.h>
+#include <atomic>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_THREADS)
+
+struct __stop_callback_base : __intrusive_node_base<__stop_callback_base> {
+ using __callback_fn_t = void(__stop_callback_base*) noexcept;
+ _LIBCPP_HIDE_FROM_ABI explicit __stop_callback_base(__callback_fn_t* __callback_fn) : __callback_fn_(__callback_fn) {}
+
+ _LIBCPP_HIDE_FROM_ABI void __invoke() noexcept { __callback_fn_(this); }
+
+ __callback_fn_t* __callback_fn_;
+ atomic<bool> __completed_ = false;
+ bool* __destroyed_ = nullptr;
+};
+
+class __stop_state {
+ static constexpr uint32_t __stop_requested_bit = 1;
+ static constexpr uint32_t __callback_list_locked_bit = 1 << 1;
+ static constexpr uint32_t __stop_source_counter_shift = 2;
+
+ // The "stop_source counter" is not used for lifetime reference counting.
+ // When the number of stop_source reaches 0, the remaining stop_tokens's
+ // stop_possible will return false. We need this counter to track this.
+ //
+ // The "callback list locked" bit implements the atomic_unique_lock to
+ // guard the operations on the callback list
+ //
+ // 31 - 2 | 1 | 0 |
+ // stop_source counter | callback list locked | stop_requested |
+ atomic<uint32_t> __state_ = 0;
+
+ // Reference count for stop_token + stop_callback + stop_source
+ // When the counter reaches zero, the state is destroyed
+ // It is used by __intrusive_shared_ptr, but it is stored here for better layout
+ atomic<uint32_t> __ref_count_ = 0;
+
+ using __state_t = uint32_t;
+ using __callback_list_lock = __atomic_unique_lock<__state_t, __callback_list_locked_bit>;
+ using __callback_list = __intrusive_list_view<__stop_callback_base>;
+
+ __callback_list __callback_list_;
+ __thread_id __requesting_thread_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __stop_state() noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI void __increment_stop_source_counter() noexcept {
+ _LIBCPP_ASSERT_UNCATEGORIZED(
+ __state_.load(std::memory_order_relaxed) <= static_cast<__state_t>(~(1 << __stop_source_counter_shift)),
+ "stop_source's counter reaches the maximum. Incrementing the counter will overflow");
+ __state_.fetch_add(1 << __stop_source_counter_shift, std::memory_order_relaxed);
+ }
+
+ // We are not destroying the object after counter decrements to zero, nor do we have
+ // operations depend on the ordering of decrementing the counter. relaxed is enough.
+ _LIBCPP_HIDE_FROM_ABI void __decrement_stop_source_counter() noexcept {
+ _LIBCPP_ASSERT_UNCATEGORIZED(
+ __state_.load(std::memory_order_relaxed) >= static_cast<__state_t>(1 << __stop_source_counter_shift),
+ "stop_source's counter is 0. Decrementing the counter will underflow");
+ __state_.fetch_sub(1 << __stop_source_counter_shift, std::memory_order_relaxed);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool __stop_requested() const noexcept {
+ // acquire because [thread.stoptoken.intro] A call to request_stop that returns true
+ // synchronizes with a call to stop_requested on an associated stop_token or stop_source
+ // object that returns true.
+ // request_stop's compare_exchange_weak has release which syncs with this acquire
+ return (__state_.load(std::memory_order_acquire) & __stop_requested_bit) != 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool __stop_possible_for_stop_token() const noexcept {
+ // [stoptoken.mem] false if "a stop request was not made and there are no associated stop_source objects"
+ // Todo: Can this be std::memory_order_relaxed as the standard does not say anything except not to introduce data
+ // race?
+ __state_t __curent_state = __state_.load(std::memory_order_acquire);
+ return ((__curent_state & __stop_requested_bit) != 0) || ((__curent_state >> __stop_source_counter_shift) != 0);
+ }
+
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool __request_stop() noexcept {
+ auto __cb_list_lock = __try_lock_for_request_stop();
+ if (!__cb_list_lock.__owns_lock()) {
+ return false;
+ }
+ __requesting_thread_ = this_thread::get_id();
+
+ while (!__callback_list_.__empty()) {
+ auto __cb = __callback_list_.__pop_front();
+
+ // allow other callbacks to be removed while invoking the current callback
+ __cb_list_lock.__unlock();
+
+ bool __destroyed = false;
+ __cb->__destroyed_ = &__destroyed;
+
+ __cb->__invoke();
+
+ // __cb's invoke function could potentially delete itself. We need to check before accessing __cb's member
+ if (!__destroyed) {
+ // needs to set __destroyed_ pointer to nullptr, otherwise it points to a local variable
+ // which is to be destroyed at the end of the loop
+ __cb->__destroyed_ = nullptr;
+
+ // [stopcallback.cons] If callback is concurrently executing on another thread, then the return
+ // from the invocation of callback strongly happens before ([intro.races]) callback is destroyed.
+ // this release syncs with the acquire in the remove_callback
+ __cb->__completed_.store(true, std::memory_order_release);
+ __cb->__completed_.notify_all();
+ }
+
+ __cb_list_lock.__lock();
+ }
+
+ return true;
+ }
+
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool __add_callback(__stop_callback_base* __cb) noexcept {
+ // If it is already stop_requested. Do not try to request it again.
+ const auto __give_up_trying_to_lock_condition = [__cb](__state_t __state) {
+ if ((__state & __stop_requested_bit) != 0) {
+ // already stop requested, synchronously run the callback and no need to lock the list again
+ __cb->__invoke();
+ return true;
+ }
+ // no stop source. no need to lock the list to add the callback as it can never be invoked
+ return (__state >> __stop_source_counter_shift) == 0;
+ };
+
+ __callback_list_lock __cb_list_lock(__state_, __give_up_trying_to_lock_condition);
+
+ if (!__cb_list_lock.__owns_lock()) {
+ return false;
+ }
+
+ __callback_list_.__push_front(__cb);
+
+ return true;
+ // unlock here: [thread.stoptoken.intro] Registration of a callback synchronizes with the invocation of
+ // that callback.
+ // Note: this release sync with the acquire in the request_stop' __try_lock_for_request_stop
+ }
+
+ // called by the destructor of stop_callback
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void __remove_callback(__stop_callback_base* __cb) noexcept {
+ __callback_list_lock __cb_list_lock(__state_);
+
+ // under below condition, the request_stop call just popped __cb from the list and could execute it now
+ bool __potentially_executing_now = __cb->__prev_ == nullptr && !__callback_list_.__is_head(__cb);
+
+ if (__potentially_executing_now) {
+ auto __requested_thread = __requesting_thread_;
+ __cb_list_lock.__unlock();
+
+ if (std::this_thread::get_id() != __requested_thread) {
+ // [stopcallback.cons] If callback is concurrently executing on another thread, then the return
+ // from the invocation of callback strongly happens before ([intro.races]) callback is destroyed.
+ __cb->__completed_.wait(false, std::memory_order_acquire);
+ } else {
+ // The destructor of stop_callback runs on the same thread of the thread that invokes the callback.
+ // The callback is potentially invoking its own destuctor. Set the flag to avoid accessing destroyed
+ // members on the invoking side
+ if (__cb->__destroyed_) {
+ *__cb->__destroyed_ = true;
+ }
+ }
+ } else {
+ __callback_list_.__remove(__cb);
+ }
+ }
+
+private:
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI __callback_list_lock __try_lock_for_request_stop() noexcept {
+ // If it is already stop_requested, do not try to request stop or lock the list again.
+ const auto __lock_fail_condition = [](__state_t __state) { return (__state & __stop_requested_bit) != 0; };
+
+ // set locked and requested bit at the same time
+ const auto __after_lock_state = [](__state_t __state) {
+ return __state | __callback_list_locked_bit | __stop_requested_bit;
+ };
+
+ // acq because [thread.stoptoken.intro] Registration of a callback synchronizes with the invocation of that
+ // callback. We are going to invoke the callback after getting the lock, acquire so that we can see the
+ // registration of a callback (and other writes that happens-before the add_callback)
+ // Note: the rel (unlock) in the add_callback syncs with this acq
+ // rel because [thread.stoptoken.intro] A call to request_stop that returns true synchronizes with a call
+ // to stop_requested on an associated stop_token or stop_source object that returns true.
+ // We need to make sure that all writes (including user code) before request_stop will be made visible
+ // to the threads that waiting for `stop_requested == true`
+ // Note: this rel syncs with the acq in `stop_requested`
+ const auto __locked_ordering = std::memory_order_acq_rel;
+
+ return __callback_list_lock(__state_, __lock_fail_condition, __after_lock_state, __locked_ordering);
+ }
+
+ template <class _Tp>
+ friend struct __intrusive_shared_ptr_traits;
+};
+
+template <class _Tp>
+struct __intrusive_shared_ptr_traits;
+
+template <>
+struct __intrusive_shared_ptr_traits<__stop_state> {
+ _LIBCPP_HIDE_FROM_ABI static atomic<uint32_t>& __get_atomic_ref_count(__stop_state& __state) {
+ return __state.__ref_count_;
+ }
+};
+
+#endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_THREADS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___STOP_TOKEN_STOP_STATE_H
diff --git a/libcxx/include/__cxx03/__stop_token/stop_token.h b/libcxx/include/__cxx03/__stop_token/stop_token.h
new file mode 100644
index 00000000000000..1bd75cbbf6f8d8
--- /dev/null
+++ b/libcxx/include/__cxx03/__stop_token/stop_token.h
@@ -0,0 +1,63 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STOP_TOKEN_STOP_TOKEN_H
+#define _LIBCPP___STOP_TOKEN_STOP_TOKEN_H
+
+#include <__config>
+#include <__stop_token/intrusive_shared_ptr.h>
+#include <__stop_token/stop_state.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
+
+class _LIBCPP_AVAILABILITY_SYNC stop_token {
+public:
+ _LIBCPP_HIDE_FROM_ABI stop_token() noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI stop_token(const stop_token&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI stop_token(stop_token&&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI stop_token& operator=(const stop_token&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI stop_token& operator=(stop_token&&) noexcept = default;
+ _LIBCPP_HIDE_FROM_ABI ~stop_token() = default;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(stop_token& __other) noexcept { __state_.swap(__other.__state_); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_requested() const noexcept {
+ return __state_ != nullptr && __state_->__stop_requested();
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_possible() const noexcept {
+ return __state_ != nullptr && __state_->__stop_possible_for_stop_token();
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI friend bool operator==(const stop_token&, const stop_token&) noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI friend void swap(stop_token& __lhs, stop_token& __rhs) noexcept { __lhs.swap(__rhs); }
+
+private:
+ __intrusive_shared_ptr<__stop_state> __state_;
+
+ friend class stop_source;
+ template <class _Tp>
+ friend class stop_callback;
+
+ _LIBCPP_HIDE_FROM_ABI explicit stop_token(const __intrusive_shared_ptr<__stop_state>& __state) : __state_(__state) {}
+};
+
+#endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___STOP_TOKEN_STOP_TOKEN_H
diff --git a/libcxx/include/__cxx03/__string/char_traits.h b/libcxx/include/__cxx03/__string/char_traits.h
new file mode 100644
index 00000000000000..2660ac2ede2d5c
--- /dev/null
+++ b/libcxx/include/__cxx03/__string/char_traits.h
@@ -0,0 +1,543 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STRING_CHAR_TRAITS_H
+#define _LIBCPP___STRING_CHAR_TRAITS_H
+
+#include <__algorithm/fill_n.h>
+#include <__algorithm/find.h>
+#include <__algorithm/find_end.h>
+#include <__algorithm/find_first_of.h>
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__compare/ordering.h>
+#include <__config>
+#include <__functional/hash.h>
+#include <__functional/identity.h>
+#include <__iterator/iterator_traits.h>
+#include <__string/constexpr_c_functions.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__utility/is_pointer_in_range.h>
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
+#include <iosfwd>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+# include <cwchar> // for wmemcpy
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT>
+struct char_traits;
+/*
+The Standard does not define the base template for char_traits because it is impossible to provide
+a correct definition for arbitrary character types. Instead, it requires implementations to provide
+specializations for predefined character types like `char`, `wchar_t` and others. We provide this as
+exposition-only to document what members a char_traits specialization should provide:
+{
+ using char_type = _CharT;
+ using int_type = ...;
+ using off_type = ...;
+ using pos_type = ...;
+ using state_type = ...;
+
+ static void assign(char_type&, const char_type&);
+ static bool eq(char_type, char_type);
+ static bool lt(char_type, char_type);
+
+ static int compare(const char_type*, const char_type*, size_t);
+ static size_t length(const char_type*);
+ static const char_type* find(const char_type*, size_t, const char_type&);
+ static char_type* move(char_type*, const char_type*, size_t);
+ static char_type* copy(char_type*, const char_type*, size_t);
+ static char_type* assign(char_type*, size_t, char_type);
+
+ static int_type not_eof(int_type);
+ static char_type to_char_type(int_type);
+ static int_type to_int_type(char_type);
+ static bool eq_int_type(int_type, int_type);
+ static int_type eof();
+};
+*/
+
+// char_traits<char>
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS char_traits<char> {
+ using char_type = char;
+ using int_type = int;
+ using off_type = streamoff;
+ using pos_type = streampos;
+ using state_type = mbstate_t;
+#if _LIBCPP_STD_VER >= 20
+ using comparison_category = strong_ordering;
+#endif
+
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 void
+ assign(char_type& __c1, const char_type& __c2) _NOEXCEPT {
+ __c1 = __c2;
+ }
+
+ // TODO: Make this _LIBCPP_HIDE_FROM_ABI
+ static inline _LIBCPP_HIDDEN _LIBCPP_CONSTEXPR bool eq(char_type __c1, char_type __c2) _NOEXCEPT {
+ return __c1 == __c2;
+ }
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool lt(char_type __c1, char_type __c2) _NOEXCEPT {
+ return (unsigned char)__c1 < (unsigned char)__c2;
+ }
+
+ // __constexpr_memcmp requires a trivially lexicographically comparable type, but char is not when char is a signed
+ // type
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 int
+ compare(const char_type* __lhs, const char_type* __rhs, size_t __count) _NOEXCEPT {
+ if (__libcpp_is_constant_evaluated()) {
+#ifdef _LIBCPP_COMPILER_CLANG_BASED
+ return __builtin_memcmp(__lhs, __rhs, __count);
+#else
+ while (__count != 0) {
+ if (lt(*__lhs, *__rhs))
+ return -1;
+ if (lt(*__rhs, *__lhs))
+ return 1;
+
+ __count -= sizeof(char_type);
+ ++__lhs;
+ ++__rhs;
+ }
+ return 0;
+#endif // _LIBCPP_COMPILER_CLANG_BASED
+ } else {
+ return __builtin_memcmp(__lhs, __rhs, __count);
+ }
+ }
+
+ static inline _LIBCPP_HIDE_FROM_ABI size_t _LIBCPP_CONSTEXPR_SINCE_CXX17 length(const char_type* __s) _NOEXCEPT {
+ return std::__constexpr_strlen(__s);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const char_type*
+ find(const char_type* __s, size_t __n, const char_type& __a) _NOEXCEPT {
+ if (__n == 0)
+ return nullptr;
+ return std::__constexpr_memchr(__s, __a, __n);
+ }
+
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
+ move(char_type* __s1, const char_type* __s2, size_t __n) _NOEXCEPT {
+ return std::__constexpr_memmove(__s1, __s2, __element_count(__n));
+ }
+
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
+ copy(char_type* __s1, const char_type* __s2, size_t __n) _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(!std::__is_pointer_in_range(__s1, __s1 + __n, __s2),
+ "char_traits::copy: source and destination ranges overlap");
+ std::__constexpr_memmove(__s1, __s2, __element_count(__n));
+ return __s1;
+ }
+
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
+ assign(char_type* __s, size_t __n, char_type __a) _NOEXCEPT {
+ std::fill_n(__s, __n, __a);
+ return __s;
+ }
+
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int_type not_eof(int_type __c) _NOEXCEPT {
+ return eq_int_type(__c, eof()) ? ~eof() : __c;
+ }
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR char_type to_char_type(int_type __c) _NOEXCEPT {
+ return char_type(__c);
+ }
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int_type to_int_type(char_type __c) _NOEXCEPT {
+ return int_type((unsigned char)__c);
+ }
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool eq_int_type(int_type __c1, int_type __c2) _NOEXCEPT {
+ return __c1 == __c2;
+ }
+ static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int_type eof() _NOEXCEPT { return int_type(EOF); }
+};
+
+template <class _CharT, class _IntT, _IntT _EOFVal>
+struct __char_traits_base {
+ using char_type = _CharT;
+ using int_type = _IntT;
+ using off_type = streamoff;
+ using state_type = mbstate_t;
+#if _LIBCPP_STD_VER >= 20
+ using comparison_category = strong_ordering;
+#endif
+
+ // There are different aliases for the different char types, but they are all aliases to this type
+ using pos_type = fpos<mbstate_t>;
+
+ _LIBCPP_HIDE_FROM_ABI static inline _LIBCPP_CONSTEXPR_SINCE_CXX17 void
+ assign(char_type& __lhs, const char_type& __rhs) _NOEXCEPT {
+ __lhs = __rhs;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR bool eq(char_type __lhs, char_type __rhs) _NOEXCEPT {
+ return __lhs == __rhs;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR bool lt(char_type __lhs, char_type __rhs) _NOEXCEPT {
+ return __lhs < __rhs;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
+ move(char_type* __dest, const char_type* __src, size_t __n) _NOEXCEPT {
+ return std::__constexpr_memmove(__dest, __src, __element_count(__n));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
+ copy(char_type* __dest, const char_type* __src, size_t __n) _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(!std::__is_pointer_in_range(__dest, __dest + __n, __src),
+ "char_traits::copy: source and destination ranges overlap");
+ return std::__constexpr_memmove(__dest, __src, __element_count(__n));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
+ assign(char_type* __str, size_t __n, char_type __fill_char) _NOEXCEPT {
+ std::fill_n(__str, __n, __fill_char);
+ return __str;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR char_type to_char_type(int_type __c) _NOEXCEPT {
+ return char_type(__c);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR int_type to_int_type(char_type __c) _NOEXCEPT { return int_type(__c); }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR bool eq_int_type(int_type __lhs, int_type __rhs) _NOEXCEPT {
+ return __lhs == __rhs;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR int_type eof() _NOEXCEPT { return _EOFVal; }
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR int_type not_eof(int_type __c) _NOEXCEPT {
+ return eq_int_type(__c, eof()) ? static_cast<int_type>(~eof()) : __c;
+ }
+};
+
+// char_traits<wchar_t>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+struct _LIBCPP_TEMPLATE_VIS char_traits<wchar_t> : __char_traits_base<wchar_t, wint_t, static_cast<wint_t>(WEOF)> {
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 int
+ compare(const char_type* __s1, const char_type* __s2, size_t __n) _NOEXCEPT {
+ if (__n == 0)
+ return 0;
+ return std::__constexpr_wmemcmp(__s1, __s2, __n);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 size_t length(const char_type* __s) _NOEXCEPT {
+ return std::__constexpr_wcslen(__s);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const char_type*
+ find(const char_type* __s, size_t __n, const char_type& __a) _NOEXCEPT {
+ if (__n == 0)
+ return nullptr;
+ return std::__constexpr_wmemchr(__s, __a, __n);
+ }
+};
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS char_traits<char8_t>
+ : __char_traits_base<char8_t, unsigned int, static_cast<unsigned int>(EOF)> {
+ static _LIBCPP_HIDE_FROM_ABI constexpr int
+ compare(const char_type* __s1, const char_type* __s2, size_t __n) noexcept {
+ return std::__constexpr_memcmp(__s1, __s2, __element_count(__n));
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI constexpr size_t length(const char_type* __str) noexcept {
+ return std::__constexpr_strlen(__str);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr const char_type*
+ find(const char_type* __s, size_t __n, const char_type& __a) noexcept {
+ return std::__constexpr_memchr(__s, __a, __n);
+ }
+};
+
+#endif // _LIBCPP_HAS_NO_CHAR8_T
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS char_traits<char16_t>
+ : __char_traits_base<char16_t, uint_least16_t, static_cast<uint_least16_t>(0xFFFF)> {
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX17 int
+ compare(const char_type* __s1, const char_type* __s2, size_t __n) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX17 size_t length(const char_type* __s) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX17 const char_type*
+ find(const char_type* __s, size_t __n, const char_type& __a) _NOEXCEPT {
+ __identity __proj;
+ const char_type* __match = std::__find(__s, __s + __n, __a, __proj);
+ if (__match == __s + __n)
+ return nullptr;
+ return __match;
+ }
+};
+
+inline _LIBCPP_CONSTEXPR_SINCE_CXX17 int
+char_traits<char16_t>::compare(const char_type* __s1, const char_type* __s2, size_t __n) _NOEXCEPT {
+ for (; __n; --__n, ++__s1, ++__s2) {
+ if (lt(*__s1, *__s2))
+ return -1;
+ if (lt(*__s2, *__s1))
+ return 1;
+ }
+ return 0;
+}
+
+inline _LIBCPP_CONSTEXPR_SINCE_CXX17 size_t char_traits<char16_t>::length(const char_type* __s) _NOEXCEPT {
+ size_t __len = 0;
+ for (; !eq(*__s, char_type(0)); ++__s)
+ ++__len;
+ return __len;
+}
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS char_traits<char32_t>
+ : __char_traits_base<char32_t, uint_least32_t, static_cast<uint_least32_t>(0xFFFFFFFF)> {
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX17 int
+ compare(const char_type* __s1, const char_type* __s2, size_t __n) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX17 size_t length(const char_type* __s) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX17 const char_type*
+ find(const char_type* __s, size_t __n, const char_type& __a) _NOEXCEPT {
+ __identity __proj;
+ const char_type* __match = std::__find(__s, __s + __n, __a, __proj);
+ if (__match == __s + __n)
+ return nullptr;
+ return __match;
+ }
+};
+
+inline _LIBCPP_CONSTEXPR_SINCE_CXX17 int
+char_traits<char32_t>::compare(const char_type* __s1, const char_type* __s2, size_t __n) _NOEXCEPT {
+ for (; __n; --__n, ++__s1, ++__s2) {
+ if (lt(*__s1, *__s2))
+ return -1;
+ if (lt(*__s2, *__s1))
+ return 1;
+ }
+ return 0;
+}
+
+inline _LIBCPP_CONSTEXPR_SINCE_CXX17 size_t char_traits<char32_t>::length(const char_type* __s) _NOEXCEPT {
+ size_t __len = 0;
+ for (; !eq(*__s, char_type(0)); ++__s)
+ ++__len;
+ return __len;
+}
+
+// helper fns for basic_string and string_view
+
+// __str_find
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_find(const _CharT* __p, _SizeT __sz, _CharT __c, _SizeT __pos) _NOEXCEPT {
+ if (__pos >= __sz)
+ return __npos;
+ const _CharT* __r = _Traits::find(__p + __pos, __sz - __pos, __c);
+ if (__r == nullptr)
+ return __npos;
+ return static_cast<_SizeT>(__r - __p);
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI inline _LIBCPP_CONSTEXPR_SINCE_CXX14 const _CharT* __search_substring(
+ const _CharT* __first1, const _CharT* __last1, const _CharT* __first2, const _CharT* __last2) _NOEXCEPT {
+ // Take advantage of knowing source and pattern lengths.
+ // Stop short when source is smaller than pattern.
+ const ptrdiff_t __len2 = __last2 - __first2;
+ if (__len2 == 0)
+ return __first1;
+
+ ptrdiff_t __len1 = __last1 - __first1;
+ if (__len1 < __len2)
+ return __last1;
+
+ // First element of __first2 is loop invariant.
+ _CharT __f2 = *__first2;
+ while (true) {
+ __len1 = __last1 - __first1;
+ // Check whether __first1 still has at least __len2 bytes.
+ if (__len1 < __len2)
+ return __last1;
+
+ // Find __f2 the first byte matching in __first1.
+ __first1 = _Traits::find(__first1, __len1 - __len2 + 1, __f2);
+ if (__first1 == nullptr)
+ return __last1;
+
+ // It is faster to compare from the first byte of __first1 even if we
+ // already know that it matches the first byte of __first2: this is because
+ // __first2 is most likely aligned, as it is user's "pattern" string, and
+ // __first1 + 1 is most likely not aligned, as the match is in the middle of
+ // the string.
+ if (_Traits::compare(__first1, __first2, __len2) == 0)
+ return __first1;
+
+ ++__first1;
+ }
+}
+
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_find(const _CharT* __p, _SizeT __sz, const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT {
+ if (__pos > __sz)
+ return __npos;
+
+ if (__n == 0) // There is nothing to search, just return __pos.
+ return __pos;
+
+ const _CharT* __r = std::__search_substring<_CharT, _Traits>(__p + __pos, __p + __sz, __s, __s + __n);
+
+ if (__r == __p + __sz)
+ return __npos;
+ return static_cast<_SizeT>(__r - __p);
+}
+
+// __str_rfind
+
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_rfind(const _CharT* __p, _SizeT __sz, _CharT __c, _SizeT __pos) _NOEXCEPT {
+ if (__sz < 1)
+ return __npos;
+ if (__pos < __sz)
+ ++__pos;
+ else
+ __pos = __sz;
+ for (const _CharT* __ps = __p + __pos; __ps != __p;) {
+ if (_Traits::eq(*--__ps, __c))
+ return static_cast<_SizeT>(__ps - __p);
+ }
+ return __npos;
+}
+
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_rfind(const _CharT* __p, _SizeT __sz, const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT {
+ __pos = std::min(__pos, __sz);
+ if (__n < __sz - __pos)
+ __pos += __n;
+ else
+ __pos = __sz;
+ const _CharT* __r = std::__find_end_classic(__p, __p + __pos, __s, __s + __n, _Traits::eq);
+ if (__n > 0 && __r == __p + __pos)
+ return __npos;
+ return static_cast<_SizeT>(__r - __p);
+}
+
+// __str_find_first_of
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_find_first_of(const _CharT* __p, _SizeT __sz, const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT {
+ if (__pos >= __sz || __n == 0)
+ return __npos;
+ const _CharT* __r = std::__find_first_of_ce(__p + __pos, __p + __sz, __s, __s + __n, _Traits::eq);
+ if (__r == __p + __sz)
+ return __npos;
+ return static_cast<_SizeT>(__r - __p);
+}
+
+// __str_find_last_of
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_find_last_of(const _CharT* __p, _SizeT __sz, const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT {
+ if (__n != 0) {
+ if (__pos < __sz)
+ ++__pos;
+ else
+ __pos = __sz;
+ for (const _CharT* __ps = __p + __pos; __ps != __p;) {
+ const _CharT* __r = _Traits::find(__s, __n, *--__ps);
+ if (__r)
+ return static_cast<_SizeT>(__ps - __p);
+ }
+ }
+ return __npos;
+}
+
+// __str_find_first_not_of
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_find_first_not_of(const _CharT* __p, _SizeT __sz, const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT {
+ if (__pos < __sz) {
+ const _CharT* __pe = __p + __sz;
+ for (const _CharT* __ps = __p + __pos; __ps != __pe; ++__ps)
+ if (_Traits::find(__s, __n, *__ps) == nullptr)
+ return static_cast<_SizeT>(__ps - __p);
+ }
+ return __npos;
+}
+
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_find_first_not_of(const _CharT* __p, _SizeT __sz, _CharT __c, _SizeT __pos) _NOEXCEPT {
+ if (__pos < __sz) {
+ const _CharT* __pe = __p + __sz;
+ for (const _CharT* __ps = __p + __pos; __ps != __pe; ++__ps)
+ if (!_Traits::eq(*__ps, __c))
+ return static_cast<_SizeT>(__ps - __p);
+ }
+ return __npos;
+}
+
+// __str_find_last_not_of
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_find_last_not_of(const _CharT* __p, _SizeT __sz, const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT {
+ if (__pos < __sz)
+ ++__pos;
+ else
+ __pos = __sz;
+ for (const _CharT* __ps = __p + __pos; __ps != __p;)
+ if (_Traits::find(__s, __n, *--__ps) == nullptr)
+ return static_cast<_SizeT>(__ps - __p);
+ return __npos;
+}
+
+template <class _CharT, class _SizeT, class _Traits, _SizeT __npos>
+inline _SizeT _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+__str_find_last_not_of(const _CharT* __p, _SizeT __sz, _CharT __c, _SizeT __pos) _NOEXCEPT {
+ if (__pos < __sz)
+ ++__pos;
+ else
+ __pos = __sz;
+ for (const _CharT* __ps = __p + __pos; __ps != __p;)
+ if (!_Traits::eq(*--__ps, __c))
+ return static_cast<_SizeT>(__ps - __p);
+ return __npos;
+}
+
+template <class _Ptr>
+inline _LIBCPP_HIDE_FROM_ABI size_t __do_string_hash(_Ptr __p, _Ptr __e) {
+ typedef typename iterator_traits<_Ptr>::value_type value_type;
+ return __murmur2_or_cityhash<size_t>()(__p, (__e - __p) * sizeof(value_type));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___STRING_CHAR_TRAITS_H
diff --git a/libcxx/include/__cxx03/__string/constexpr_c_functions.h b/libcxx/include/__cxx03/__string/constexpr_c_functions.h
new file mode 100644
index 00000000000000..a978f816f18978
--- /dev/null
+++ b/libcxx/include/__cxx03/__string/constexpr_c_functions.h
@@ -0,0 +1,234 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STRING_CONSTEXPR_C_FUNCTIONS_H
+#define _LIBCPP___STRING_CONSTEXPR_C_FUNCTIONS_H
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory/construct_at.h>
+#include <__type_traits/datasizeof.h>
+#include <__type_traits/is_always_bitcastable.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_equality_comparable.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <__type_traits/is_trivially_lexicographically_comparable.h>
+#include <__type_traits/remove_cv.h>
+#include <__utility/is_pointer_in_range.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Type used to encode that a function takes an integer that represents a number
+// of elements as opposed to a number of bytes.
+enum class __element_count : size_t {};
+
+template <class _Tp>
+inline const bool __is_char_type = false;
+
+template <>
+inline const bool __is_char_type<char> = true;
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <>
+inline const bool __is_char_type<char8_t> = true;
+#endif
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 size_t __constexpr_strlen(const _Tp* __str) _NOEXCEPT {
+ static_assert(__is_char_type<_Tp>, "__constexpr_strlen only works with char and char8_t");
+ // GCC currently doesn't support __builtin_strlen for heap-allocated memory during constant evaluation.
+ // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70816
+ if (__libcpp_is_constant_evaluated()) {
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_COMPILER_CLANG_BASED)
+ if constexpr (is_same_v<_Tp, char>)
+ return __builtin_strlen(__str);
+#endif
+ size_t __i = 0;
+ for (; __str[__i] != '\0'; ++__i)
+ ;
+ return __i;
+ }
+ return __builtin_strlen(reinterpret_cast<const char*>(__str));
+}
+
+// Because of __libcpp_is_trivially_lexicographically_comparable we know that comparing the object representations is
+// equivalent to a std::memcmp. Since we have multiple objects contiguously in memory, we can call memcmp once instead
+// of invoking it on every object individually.
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int
+__constexpr_memcmp(const _Tp* __lhs, const _Up* __rhs, __element_count __n) {
+ static_assert(__libcpp_is_trivially_lexicographically_comparable<_Tp, _Up>::value,
+ "_Tp and _Up have to be trivially lexicographically comparable");
+
+ auto __count = static_cast<size_t>(__n);
+
+ if (__libcpp_is_constant_evaluated()) {
+#ifdef _LIBCPP_COMPILER_CLANG_BASED
+ if (sizeof(_Tp) == 1 && !is_same<_Tp, bool>::value)
+ return __builtin_memcmp(__lhs, __rhs, __count * sizeof(_Tp));
+#endif
+
+ while (__count != 0) {
+ if (*__lhs < *__rhs)
+ return -1;
+ if (*__rhs < *__lhs)
+ return 1;
+
+ --__count;
+ ++__lhs;
+ ++__rhs;
+ }
+ return 0;
+ } else {
+ return __builtin_memcmp(__lhs, __rhs, __count * sizeof(_Tp));
+ }
+}
+
+// Because of __libcpp_is_trivially_equality_comparable we know that comparing the object representations is equivalent
+// to a std::memcmp(...) == 0. Since we have multiple objects contiguously in memory, we can call memcmp once instead
+// of invoking it on every object individually.
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+__constexpr_memcmp_equal(const _Tp* __lhs, const _Up* __rhs, __element_count __n) {
+ static_assert(__libcpp_is_trivially_equality_comparable<_Tp, _Up>::value,
+ "_Tp and _Up have to be trivially equality comparable");
+
+ auto __count = static_cast<size_t>(__n);
+
+ if (__libcpp_is_constant_evaluated()) {
+#ifdef _LIBCPP_COMPILER_CLANG_BASED
+ if (sizeof(_Tp) == 1 && is_integral<_Tp>::value && !is_same<_Tp, bool>::value)
+ return __builtin_memcmp(__lhs, __rhs, __count * sizeof(_Tp)) == 0;
+#endif
+ while (__count != 0) {
+ if (*__lhs != *__rhs)
+ return false;
+
+ --__count;
+ ++__lhs;
+ ++__rhs;
+ }
+ return true;
+ } else {
+ return ::__builtin_memcmp(__lhs, __rhs, __count * sizeof(_Tp)) == 0;
+ }
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp* __constexpr_memchr(_Tp* __str, _Up __value, size_t __count) {
+ static_assert(sizeof(_Tp) == 1 && __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value,
+ "Calling memchr on non-trivially equality comparable types is unsafe.");
+
+ if (__libcpp_is_constant_evaluated()) {
+// use __builtin_char_memchr to optimize constexpr evaluation if we can
+#if _LIBCPP_STD_VER >= 17 && __has_builtin(__builtin_char_memchr)
+ if constexpr (is_same_v<remove_cv_t<_Tp>, char> && is_same_v<remove_cv_t<_Up>, char>)
+ return __builtin_char_memchr(__str, __value, __count);
+#endif
+
+ for (; __count; --__count) {
+ if (*__str == __value)
+ return __str;
+ ++__str;
+ }
+ return nullptr;
+ } else {
+ char __value_buffer = 0;
+ __builtin_memcpy(&__value_buffer, &__value, sizeof(char));
+ return static_cast<_Tp*>(__builtin_memchr(__str, __value_buffer, __count));
+ }
+}
+
+// This function performs an assignment to an existing, already alive TriviallyCopyable object
+// from another TriviallyCopyable object.
+//
+// It basically works around the fact that TriviallyCopyable objects are not required to be
+// syntactically copy/move constructible or copy/move assignable. Technically, only one of the
+// four operations is required to be syntactically valid -- but at least one definitely has to
+// be valid.
+//
+// This is necessary in order to implement __constexpr_memmove below in a way that mirrors as
+// closely as possible what the compiler's __builtin_memmove is able to do.
+template <class _Tp, class _Up, __enable_if_t<is_assignable<_Tp&, _Up const&>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp& __assign_trivially_copyable(_Tp& __dest, _Up const& __src) {
+ __dest = __src;
+ return __dest;
+}
+
+// clang-format off
+template <class _Tp, class _Up, __enable_if_t<!is_assignable<_Tp&, _Up const&>::value &&
+ is_assignable<_Tp&, _Up&&>::value, int> = 0>
+// clang-format on
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp& __assign_trivially_copyable(_Tp& __dest, _Up& __src) {
+ __dest =
+ static_cast<_Up&&>(__src); // this is safe, we're not actually moving anything since the assignment is trivial
+ return __dest;
+}
+
+// clang-format off
+template <class _Tp, class _Up, __enable_if_t<!is_assignable<_Tp&, _Up const&>::value &&
+ !is_assignable<_Tp&, _Up&&>::value &&
+ is_constructible<_Tp, _Up const&>::value, int> = 0>
+// clang-format on
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& __assign_trivially_copyable(_Tp& __dest, _Up const& __src) {
+ // _Tp is trivially destructible, so we don't need to call its destructor to end the lifetime of the object
+ // that was there previously
+ std::__construct_at(std::addressof(__dest), __src);
+ return __dest;
+}
+
+// clang-format off
+template <class _Tp, class _Up, __enable_if_t<!is_assignable<_Tp&, _Up const&>::value &&
+ !is_assignable<_Tp&, _Up&&>::value &&
+ !is_constructible<_Tp, _Up const&>::value &&
+ is_constructible<_Tp, _Up&&>::value, int> = 0>
+// clang-format on
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& __assign_trivially_copyable(_Tp& __dest, _Up& __src) {
+ // _Tp is trivially destructible, so we don't need to call its destructor to end the lifetime of the object
+ // that was there previously
+ std::__construct_at(
+ std::addressof(__dest),
+ static_cast<_Up&&>(__src)); // this is safe, we're not actually moving anything since the constructor is trivial
+ return __dest;
+}
+
+template <class _Tp, class _Up, __enable_if_t<__is_always_bitcastable<_Up, _Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp*
+__constexpr_memmove(_Tp* __dest, _Up* __src, __element_count __n) {
+ size_t __count = static_cast<size_t>(__n);
+ if (__libcpp_is_constant_evaluated()) {
+#ifdef _LIBCPP_COMPILER_CLANG_BASED
+ if (is_same<__remove_cv_t<_Tp>, __remove_cv_t<_Up> >::value) {
+ ::__builtin_memmove(__dest, __src, __count * sizeof(_Tp));
+ return __dest;
+ }
+#endif
+ if (std::__is_pointer_in_range(__src, __src + __count, __dest)) {
+ for (; __count > 0; --__count)
+ std::__assign_trivially_copyable(__dest[__count - 1], __src[__count - 1]);
+ } else {
+ for (size_t __i = 0; __i != __count; ++__i)
+ std::__assign_trivially_copyable(__dest[__i], __src[__i]);
+ }
+ } else if (__count > 0) {
+ ::__builtin_memmove(__dest, __src, (__count - 1) * sizeof(_Tp) + __datasizeof_v<_Tp>);
+ }
+ return __dest;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___STRING_CONSTEXPR_C_FUNCTIONS_H
diff --git a/libcxx/include/__cxx03/__string/extern_template_lists.h b/libcxx/include/__cxx03/__string/extern_template_lists.h
new file mode 100644
index 00000000000000..cc536e514d4ffe
--- /dev/null
+++ b/libcxx/include/__cxx03/__string/extern_template_lists.h
@@ -0,0 +1,133 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___STRING_EXTERN_TEMPLATE_LISTS_H
+#define _LIBCPP___STRING_EXTERN_TEMPLATE_LISTS_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// clang-format off
+
+// We maintain 2 ABI lists:
+// - _LIBCPP_STRING_V1_EXTERN_TEMPLATE_LIST
+// - _LIBCPP_STRING_UNSTABLE_EXTERN_TEMPLATE_LIST
+// As the name implies, the ABI lists define the V1 (Stable) and unstable ABI.
+//
+// For unstable, we may explicitly remove function that are external in V1,
+// and add (new) external functions to better control inlining and compiler
+// optimization opportunities.
+//
+// For stable, the ABI list should rarely change, except for adding new
+// functions supporting new c++ version / API changes. Typically entries
+// must never be removed from the stable list.
+#define _LIBCPP_STRING_V1_EXTERN_TEMPLATE_LIST(_Func, _CharType) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::replace(size_type, size_type, value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::rfind(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__init(value_type const*, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::basic_string(basic_string const&)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::replace(size_type, size_type, value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::basic_string(basic_string const&, allocator<_CharType> const&)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find_last_not_of(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::~basic_string()) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find_first_not_of(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::insert(size_type, size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::operator=(value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__init(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI const _CharType& basic_string<_CharType>::at(size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::insert(size_type, value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find_first_of(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::replace(size_type, size_type, size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::assign(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::reserve(size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::append(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::assign(basic_string const&, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::copy(value_type*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::basic_string(basic_string const&, size_type, size_type, allocator<_CharType> const&)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find(value_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__init(size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::insert(size_type, value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find_last_of(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__grow_by(size_type, size_type, size_type, size_type, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__grow_by_and_replace(size_type, size_type, size_type, size_type, size_type, size_type, value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::push_back(value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::append(size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::rfind(value_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI const basic_string<_CharType>::size_type basic_string<_CharType>::npos) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::assign(size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::erase(size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::append(basic_string const&, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI int basic_string<_CharType>::compare(value_type const*) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI int basic_string<_CharType>::compare(size_type, size_type, value_type const*) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI _CharType& basic_string<_CharType>::at(size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::assign(value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI int basic_string<_CharType>::compare(size_type, size_type, basic_string const&, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI int basic_string<_CharType>::compare(size_type, size_type, value_type const*, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::operator=(basic_string const&)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::append(value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::replace(size_type, size_type, basic_string const&, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::iterator basic_string<_CharType>::insert(basic_string::const_iterator, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::resize(size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::insert(size_type, basic_string const&, size_type, size_type))
+
+#define _LIBCPP_STRING_UNSTABLE_EXTERN_TEMPLATE_LIST(_Func, _CharType) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::replace(size_type, size_type, value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::rfind(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__init(value_type const*, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::replace(size_type, size_type, value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find_last_not_of(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::~basic_string()) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find_first_not_of(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::insert(size_type, size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::operator=(value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__init(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__init_copy_ctor_external(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI const _CharType& basic_string<_CharType>::at(size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::insert(size_type, value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find_first_of(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::replace(size_type, size_type, size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::__assign_external(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::__assign_external(value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::reserve(size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::append(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::assign(basic_string const&, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::copy(value_type*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::basic_string(basic_string const&, size_type, size_type, allocator<_CharType> const&)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find(value_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__init(size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::insert(size_type, value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find_last_of(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__grow_by_and_replace(size_type, size_type, size_type, size_type, size_type, size_type, value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::__assign_no_alias<false>(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::__assign_no_alias<true>(value_type const*, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::push_back(value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::append(size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::rfind(value_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI const basic_string<_CharType>::size_type basic_string<_CharType>::npos) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::assign(size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::__erase_external_with_move(size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::append(basic_string const&, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI int basic_string<_CharType>::compare(value_type const*) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI int basic_string<_CharType>::compare(size_type, size_type, value_type const*) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI _CharType& basic_string<_CharType>::at(size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::size_type basic_string<_CharType>::find(value_type const*, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI int basic_string<_CharType>::compare(size_type, size_type, basic_string const&, size_type, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI int basic_string<_CharType>::compare(size_type, size_type, value_type const*, size_type) const) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::append(value_type const*)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::replace(size_type, size_type, basic_string const&, size_type, size_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>::iterator basic_string<_CharType>::insert(basic_string::const_iterator, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI void basic_string<_CharType>::resize(size_type, value_type)) \
+ _Func(_LIBCPP_EXPORTED_FROM_ABI basic_string<_CharType>& basic_string<_CharType>::insert(size_type, basic_string const&, size_type, size_type))
+
+// clang-format on
+
+#endif // _LIBCPP___STRING_EXTERN_TEMPLATE_LISTS_H
diff --git a/libcxx/include/__cxx03/__support/ibm/gettod_zos.h b/libcxx/include/__cxx03/__support/ibm/gettod_zos.h
new file mode 100644
index 00000000000000..bd7e467736697b
--- /dev/null
+++ b/libcxx/include/__cxx03/__support/ibm/gettod_zos.h
@@ -0,0 +1,52 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SUPPORT_IBM_GETTOD_ZOS_H
+#define _LIBCPP___SUPPORT_IBM_GETTOD_ZOS_H
+
+#include <time.h>
+
+inline _LIBCPP_HIDE_FROM_ABI int gettimeofdayMonotonic(struct timespec64* Output) {
+ // The POSIX gettimeofday() function is not available on z/OS. Therefore,
+ // we will call stcke and other hardware instructions in implement equivalent.
+ // Note that nanoseconds alone will overflow when reaching new epoch in 2042.
+
+ struct _t {
+ uint64_t Hi;
+ uint64_t Lo;
+ };
+ struct _t Value = {0, 0};
+ uint64_t CC = 0;
+ asm(" stcke %0\n"
+ " ipm %1\n"
+ " srlg %1,%1,28\n"
+ : "=m"(Value), "+r"(CC)::);
+
+ if (CC != 0) {
+ errno = EMVSTODNOTSET;
+ return CC;
+ }
+ uint64_t us = (Value.Hi >> 4);
+ uint64_t ns = ((Value.Hi & 0x0F) << 8) + (Value.Lo >> 56);
+ ns = (ns * 1000) >> 12;
+ us = us - 2208988800000000;
+
+ register uint64_t DivPair0 asm("r0"); // dividend (upper half), remainder
+ DivPair0 = 0;
+ register uint64_t DivPair1 asm("r1"); // dividend (lower half), quotient
+ DivPair1 = us;
+ uint64_t Divisor = 1000000;
+ asm(" dlgr %0,%2" : "+r"(DivPair0), "+r"(DivPair1) : "r"(Divisor) :);
+
+ Output->tv_sec = DivPair1;
+ Output->tv_nsec = DivPair0 * 1000 + ns;
+ return 0;
+}
+
+#endif // _LIBCPP___SUPPORT_IBM_GETTOD_ZOS_H
diff --git a/libcxx/include/__cxx03/__support/ibm/locale_mgmt_zos.h b/libcxx/include/__cxx03/__support/ibm/locale_mgmt_zos.h
new file mode 100644
index 00000000000000..5fc04b6b4b2990
--- /dev/null
+++ b/libcxx/include/__cxx03/__support/ibm/locale_mgmt_zos.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SUPPORT_IBM_LOCALE_MGMT_ZOS_H
+#define _LIBCPP___SUPPORT_IBM_LOCALE_MGMT_ZOS_H
+
+#if defined(__MVS__)
+# include <locale.h>
+# include <string>
+
+# ifdef __cplusplus
+extern "C" {
+# endif
+
+# define _LC_MAX LC_MESSAGES /* highest real category */
+# define _NCAT (_LC_MAX + 1) /* maximum + 1 */
+
+# define _CATMASK(n) (1 << (n))
+# define LC_COLLATE_MASK _CATMASK(LC_COLLATE)
+# define LC_CTYPE_MASK _CATMASK(LC_CTYPE)
+# define LC_MONETARY_MASK _CATMASK(LC_MONETARY)
+# define LC_NUMERIC_MASK _CATMASK(LC_NUMERIC)
+# define LC_TIME_MASK _CATMASK(LC_TIME)
+# define LC_MESSAGES_MASK _CATMASK(LC_MESSAGES)
+# define LC_ALL_MASK (_CATMASK(_NCAT) - 1)
+
+typedef struct locale_struct {
+ int category_mask;
+ std::string lc_collate;
+ std::string lc_ctype;
+ std::string lc_monetary;
+ std::string lc_numeric;
+ std::string lc_time;
+ std::string lc_messages;
+}* locale_t;
+
+// z/OS does not have newlocale, freelocale and uselocale.
+// The functions below are workarounds in single thread mode.
+locale_t newlocale(int category_mask, const char* locale, locale_t base);
+void freelocale(locale_t locobj);
+locale_t uselocale(locale_t newloc);
+
+# ifdef __cplusplus
+}
+# endif
+#endif // defined(__MVS__)
+#endif // _LIBCPP___SUPPORT_IBM_LOCALE_MGMT_ZOS_H
diff --git a/libcxx/include/__cxx03/__support/ibm/nanosleep.h b/libcxx/include/__cxx03/__support/ibm/nanosleep.h
new file mode 100644
index 00000000000000..fadc784c0297c9
--- /dev/null
+++ b/libcxx/include/__cxx03/__support/ibm/nanosleep.h
@@ -0,0 +1,55 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SUPPORT_IBM_NANOSLEEP_H
+#define _LIBCPP___SUPPORT_IBM_NANOSLEEP_H
+
+#include <unistd.h>
+
+inline int nanosleep(const struct timespec* __req, struct timespec* __rem) {
+ // The nanosleep() function is not available on z/OS. Therefore, we will call
+ // sleep() to sleep for whole seconds and usleep() to sleep for any remaining
+ // fraction of a second. Any remaining nanoseconds will round up to the next
+ // microsecond.
+ if (__req->tv_sec < 0 || __req->tv_nsec < 0 || __req->tv_nsec > 999999999) {
+ errno = EINVAL;
+ return -1;
+ }
+ long __micro_sec = (__req->tv_nsec + 999) / 1000;
+ time_t __sec = __req->tv_sec;
+ if (__micro_sec > 999999) {
+ ++__sec;
+ __micro_sec -= 1000000;
+ }
+ __sec = static_cast<time_t>(sleep(static_cast<unsigned int>(__sec)));
+ if (__sec) {
+ if (__rem) {
+ // Updating the remaining time to sleep in case of unsuccessful call to sleep().
+ __rem->tv_sec = __sec;
+ __rem->tv_nsec = __micro_sec * 1000;
+ }
+ errno = EINTR;
+ return -1;
+ }
+ if (__micro_sec) {
+ int __rt = usleep(static_cast<unsigned int>(__micro_sec));
+ if (__rt != 0 && __rem) {
+ // The usleep() does not provide the amount of remaining time upon its failure,
+ // so the time slept will be ignored.
+ __rem->tv_sec = 0;
+ __rem->tv_nsec = __micro_sec * 1000;
+ // The errno is already set.
+ return -1;
+ }
+ return __rt;
+ }
+ return 0;
+}
+
+#endif // _LIBCPP___SUPPORT_IBM_NANOSLEEP_H
diff --git a/libcxx/include/__cxx03/__support/xlocale/__nop_locale_mgmt.h b/libcxx/include/__cxx03/__support/xlocale/__nop_locale_mgmt.h
new file mode 100644
index 00000000000000..b9ffcbe1622d51
--- /dev/null
+++ b/libcxx/include/__cxx03/__support/xlocale/__nop_locale_mgmt.h
@@ -0,0 +1,35 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SUPPORT_XLOCALE_NOP_LOCALE_MGMT_H
+#define _LIBCPP___SUPPORT_XLOCALE_NOP_LOCALE_MGMT_H
+
+#include <__config>
+
+// Patch over lack of extended locale support
+typedef void* locale_t;
+
+inline _LIBCPP_HIDE_FROM_ABI locale_t duplocale(locale_t) { return NULL; }
+
+inline _LIBCPP_HIDE_FROM_ABI void freelocale(locale_t) {}
+
+inline _LIBCPP_HIDE_FROM_ABI locale_t newlocale(int, const char*, locale_t) { return NULL; }
+
+inline _LIBCPP_HIDE_FROM_ABI locale_t uselocale(locale_t) { return NULL; }
+
+#define LC_COLLATE_MASK (1 << LC_COLLATE)
+#define LC_CTYPE_MASK (1 << LC_CTYPE)
+#define LC_MESSAGES_MASK (1 << LC_MESSAGES)
+#define LC_MONETARY_MASK (1 << LC_MONETARY)
+#define LC_NUMERIC_MASK (1 << LC_NUMERIC)
+#define LC_TIME_MASK (1 << LC_TIME)
+#define LC_ALL_MASK \
+ (LC_COLLATE_MASK | LC_CTYPE_MASK | LC_MONETARY_MASK | LC_NUMERIC_MASK | LC_TIME_MASK | LC_MESSAGES_MASK)
+
+#endif // _LIBCPP___SUPPORT_XLOCALE_NOP_LOCALE_MGMT_H
diff --git a/libcxx/include/__cxx03/__support/xlocale/__posix_l_fallback.h b/libcxx/include/__cxx03/__support/xlocale/__posix_l_fallback.h
new file mode 100644
index 00000000000000..8a3a6f27f48dde
--- /dev/null
+++ b/libcxx/include/__cxx03/__support/xlocale/__posix_l_fallback.h
@@ -0,0 +1,107 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// These are reimplementations of some extended locale functions ( *_l ) that
+// are normally part of POSIX. This shared implementation provides parts of the
+// extended locale support for libc's that normally don't have any (like
+// Android's bionic and Newlib).
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SUPPORT_XLOCALE_POSIX_L_FALLBACK_H
+#define _LIBCPP___SUPPORT_XLOCALE_POSIX_L_FALLBACK_H
+
+#include <__config>
+#include <ctype.h>
+#include <string.h>
+#include <time.h>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+# include <wchar.h>
+# include <wctype.h>
+#endif
+
+inline _LIBCPP_HIDE_FROM_ABI int isalnum_l(int __c, locale_t) { return ::isalnum(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int isalpha_l(int __c, locale_t) { return ::isalpha(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iscntrl_l(int __c, locale_t) { return ::iscntrl(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int isdigit_l(int __c, locale_t) { return ::isdigit(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int isgraph_l(int __c, locale_t) { return ::isgraph(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int islower_l(int __c, locale_t) { return ::islower(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int isprint_l(int __c, locale_t) { return ::isprint(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int ispunct_l(int __c, locale_t) { return ::ispunct(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int isspace_l(int __c, locale_t) { return ::isspace(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int isupper_l(int __c, locale_t) { return ::isupper(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int isxdigit_l(int __c, locale_t) { return ::isxdigit(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int toupper_l(int __c, locale_t) { return ::toupper(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int tolower_l(int __c, locale_t) { return ::tolower(__c); }
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+inline _LIBCPP_HIDE_FROM_ABI int iswalnum_l(wint_t __c, locale_t) { return ::iswalnum(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswalpha_l(wint_t __c, locale_t) { return ::iswalpha(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswblank_l(wint_t __c, locale_t) { return ::iswblank(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswcntrl_l(wint_t __c, locale_t) { return ::iswcntrl(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswdigit_l(wint_t __c, locale_t) { return ::iswdigit(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswgraph_l(wint_t __c, locale_t) { return ::iswgraph(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswlower_l(wint_t __c, locale_t) { return ::iswlower(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswprint_l(wint_t __c, locale_t) { return ::iswprint(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswpunct_l(wint_t __c, locale_t) { return ::iswpunct(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswspace_l(wint_t __c, locale_t) { return ::iswspace(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswupper_l(wint_t __c, locale_t) { return ::iswupper(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI int iswxdigit_l(wint_t __c, locale_t) { return ::iswxdigit(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI wint_t towupper_l(wint_t __c, locale_t) { return ::towupper(__c); }
+
+inline _LIBCPP_HIDE_FROM_ABI wint_t towlower_l(wint_t __c, locale_t) { return ::towlower(__c); }
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+inline _LIBCPP_HIDE_FROM_ABI int strcoll_l(const char* __s1, const char* __s2, locale_t) {
+ return ::strcoll(__s1, __s2);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t strxfrm_l(char* __dest, const char* __src, size_t __n, locale_t) {
+ return ::strxfrm(__dest, __src, __n);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t
+strftime_l(char* __s, size_t __max, const char* __format, const struct tm* __tm, locale_t) {
+ return ::strftime(__s, __max, __format, __tm);
+}
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+inline _LIBCPP_HIDE_FROM_ABI int wcscoll_l(const wchar_t* __ws1, const wchar_t* __ws2, locale_t) {
+ return ::wcscoll(__ws1, __ws2);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI size_t wcsxfrm_l(wchar_t* __dest, const wchar_t* __src, size_t __n, locale_t) {
+ return ::wcsxfrm(__dest, __src, __n);
+}
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+#endif // _LIBCPP___SUPPORT_XLOCALE_POSIX_L_FALLBACK_H
diff --git a/libcxx/include/__cxx03/__support/xlocale/__strtonum_fallback.h b/libcxx/include/__cxx03/__support/xlocale/__strtonum_fallback.h
new file mode 100644
index 00000000000000..b7eef5210ed374
--- /dev/null
+++ b/libcxx/include/__cxx03/__support/xlocale/__strtonum_fallback.h
@@ -0,0 +1,45 @@
+// -*- C++ -*-
+//===-----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// These are reimplementations of some extended locale functions ( *_l ) that
+// aren't part of POSIX. They are widely available though (GLIBC, BSD, maybe
+// others). The unifying aspect in this case is that all of these functions
+// convert strings to some numeric type.
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SUPPORT_XLOCALE_STRTONUM_FALLBACK_H
+#define _LIBCPP___SUPPORT_XLOCALE_STRTONUM_FALLBACK_H
+
+#include <__config>
+#include <stdlib.h>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+# include <wchar.h>
+#endif
+
+inline _LIBCPP_HIDE_FROM_ABI float strtof_l(const char* __nptr, char** __endptr, locale_t) {
+ return ::strtof(__nptr, __endptr);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI double strtod_l(const char* __nptr, char** __endptr, locale_t) {
+ return ::strtod(__nptr, __endptr);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long double strtold_l(const char* __nptr, char** __endptr, locale_t) {
+ return ::strtold(__nptr, __endptr);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI long long strtoll_l(const char* __nptr, char** __endptr, int __base, locale_t) {
+ return ::strtoll(__nptr, __endptr, __base);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI unsigned long long strtoull_l(const char* __nptr, char** __endptr, int __base, locale_t) {
+ return ::strtoull(__nptr, __endptr, __base);
+}
+
+#endif // _LIBCPP___SUPPORT_XLOCALE_STRTONUM_FALLBACK_H
diff --git a/libcxx/include/__cxx03/__system_error/errc.h b/libcxx/include/__cxx03/__system_error/errc.h
new file mode 100644
index 00000000000000..0004c46e2279b3
--- /dev/null
+++ b/libcxx/include/__cxx03/__system_error/errc.h
@@ -0,0 +1,266 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ERRC
+#define _LIBCPP___ERRC
+
+/*
+ system_error synopsis
+
+namespace std
+{
+
+enum class errc
+{
+ address_family_not_supported, // EAFNOSUPPORT
+ address_in_use, // EADDRINUSE
+ address_not_available, // EADDRNOTAVAIL
+ already_connected, // EISCONN
+ argument_list_too_long, // E2BIG
+ argument_out_of_domain, // EDOM
+ bad_address, // EFAULT
+ bad_file_descriptor, // EBADF
+ bad_message, // EBADMSG
+ broken_pipe, // EPIPE
+ connection_aborted, // ECONNABORTED
+ connection_already_in_progress, // EALREADY
+ connection_refused, // ECONNREFUSED
+ connection_reset, // ECONNRESET
+ cross_device_link, // EXDEV
+ destination_address_required, // EDESTADDRREQ
+ device_or_resource_busy, // EBUSY
+ directory_not_empty, // ENOTEMPTY
+ executable_format_error, // ENOEXEC
+ file_exists, // EEXIST
+ file_too_large, // EFBIG
+ filename_too_long, // ENAMETOOLONG
+ function_not_supported, // ENOSYS
+ host_unreachable, // EHOSTUNREACH
+ identifier_removed, // EIDRM
+ illegal_byte_sequence, // EILSEQ
+ inappropriate_io_control_operation, // ENOTTY
+ interrupted, // EINTR
+ invalid_argument, // EINVAL
+ invalid_seek, // ESPIPE
+ io_error, // EIO
+ is_a_directory, // EISDIR
+ message_size, // EMSGSIZE
+ network_down, // ENETDOWN
+ network_reset, // ENETRESET
+ network_unreachable, // ENETUNREACH
+ no_buffer_space, // ENOBUFS
+ no_child_process, // ECHILD
+ no_link, // ENOLINK
+ no_lock_available, // ENOLCK
+ no_message_available, // ENODATA // deprecated
+ no_message, // ENOMSG
+ no_protocol_option, // ENOPROTOOPT
+ no_space_on_device, // ENOSPC
+ no_stream_resources, // ENOSR // deprecated
+ no_such_device_or_address, // ENXIO
+ no_such_device, // ENODEV
+ no_such_file_or_directory, // ENOENT
+ no_such_process, // ESRCH
+ not_a_directory, // ENOTDIR
+ not_a_socket, // ENOTSOCK
+ not_a_stream, // ENOSTR // deprecated
+ not_connected, // ENOTCONN
+ not_enough_memory, // ENOMEM
+ not_supported, // ENOTSUP
+ operation_canceled, // ECANCELED
+ operation_in_progress, // EINPROGRESS
+ operation_not_permitted, // EPERM
+ operation_not_supported, // EOPNOTSUPP
+ operation_would_block, // EWOULDBLOCK
+ owner_dead, // EOWNERDEAD
+ permission_denied, // EACCES
+ protocol_error, // EPROTO
+ protocol_not_supported, // EPROTONOSUPPORT
+ read_only_file_system, // EROFS
+ resource_deadlock_would_occur, // EDEADLK
+ resource_unavailable_try_again, // EAGAIN
+ result_out_of_range, // ERANGE
+ state_not_recoverable, // ENOTRECOVERABLE
+ stream_timeout, // ETIME // deprecated
+ text_file_busy, // ETXTBSY
+ timed_out, // ETIMEDOUT
+ too_many_files_open_in_system, // ENFILE
+ too_many_files_open, // EMFILE
+ too_many_links, // EMLINK
+ too_many_symbolic_link_levels, // ELOOP
+ value_too_large, // EOVERFLOW
+ wrong_protocol_type // EPROTOTYPE
+};
+
+*/
+
+#include <__config>
+#include <cerrno>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// The method of pushing and popping the diagnostics fails for GCC. GCC does
+// not recognize the pragma's used to generate deprecated diagnostics for
+// macros. So GCC does not need the pushing and popping.
+//
+// TODO Remove this when the deprecated constants are removed.
+//
+// Note based on the post-review comments in
+// https://github.com/llvm/llvm-project/pull/80542 libc++ no longer deprecates
+// the macros. Since C libraries may start to deprecate these POSIX macros the
+// deprecation warning avoidance is kept.
+#if defined(_LIBCPP_COMPILER_CLANG_BASED)
+# define _LIBCPP_SUPPRESS_DEPRECATED_ERRC_PUSH _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+# define _LIBCPP_SUPPRESS_DEPRECATED_ERRC_POP _LIBCPP_SUPPRESS_DEPRECATED_POP
+#else
+# define _LIBCPP_SUPPRESS_DEPRECATED_ERRC_PUSH
+# define _LIBCPP_SUPPRESS_DEPRECATED_ERRC_POP
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Some error codes are not present on all platforms, so we provide equivalents
+// for them:
+
+// enum class errc
+//
+// LWG3869 deprecates the UNIX STREAMS macros and enum values.
+// This makes the code clumbersome:
+// - the enum value is deprecated and should show a diagnostic,
+// - the macro is deprecated and should _not_ show a diagnostic in this
+// context, and
+// - the macro is not always available.
+// This leads to the odd pushing and popping of the deprecated
+// diagnostic.
+_LIBCPP_DECLARE_STRONG_ENUM(errc){
+ address_family_not_supported = EAFNOSUPPORT,
+ address_in_use = EADDRINUSE,
+ address_not_available = EADDRNOTAVAIL,
+ already_connected = EISCONN,
+ argument_list_too_long = E2BIG,
+ argument_out_of_domain = EDOM,
+ bad_address = EFAULT,
+ bad_file_descriptor = EBADF,
+ bad_message = EBADMSG,
+ broken_pipe = EPIPE,
+ connection_aborted = ECONNABORTED,
+ connection_already_in_progress = EALREADY,
+ connection_refused = ECONNREFUSED,
+ connection_reset = ECONNRESET,
+ cross_device_link = EXDEV,
+ destination_address_required = EDESTADDRREQ,
+ device_or_resource_busy = EBUSY,
+ directory_not_empty = ENOTEMPTY,
+ executable_format_error = ENOEXEC,
+ file_exists = EEXIST,
+ file_too_large = EFBIG,
+ filename_too_long = ENAMETOOLONG,
+ function_not_supported = ENOSYS,
+ host_unreachable = EHOSTUNREACH,
+ identifier_removed = EIDRM,
+ illegal_byte_sequence = EILSEQ,
+ inappropriate_io_control_operation = ENOTTY,
+ interrupted = EINTR,
+ invalid_argument = EINVAL,
+ invalid_seek = ESPIPE,
+ io_error = EIO,
+ is_a_directory = EISDIR,
+ message_size = EMSGSIZE,
+ network_down = ENETDOWN,
+ network_reset = ENETRESET,
+ network_unreachable = ENETUNREACH,
+ no_buffer_space = ENOBUFS,
+ no_child_process = ECHILD,
+ no_link = ENOLINK,
+ no_lock_available = ENOLCK,
+ // clang-format off
+ no_message_available _LIBCPP_DEPRECATED =
+ _LIBCPP_SUPPRESS_DEPRECATED_ERRC_PUSH
+#ifdef ENODATA
+ ENODATA
+#else
+ ENOMSG
+#endif
+ _LIBCPP_SUPPRESS_DEPRECATED_ERRC_POP
+ ,
+ // clang-format on
+ no_message = ENOMSG,
+ no_protocol_option = ENOPROTOOPT,
+ no_space_on_device = ENOSPC,
+ // clang-format off
+ no_stream_resources _LIBCPP_DEPRECATED =
+ _LIBCPP_SUPPRESS_DEPRECATED_ERRC_PUSH
+#ifdef ENOSR
+ ENOSR
+#else
+ ENOMEM
+#endif
+ _LIBCPP_SUPPRESS_DEPRECATED_ERRC_POP
+ ,
+ // clang-format on
+ no_such_device_or_address = ENXIO,
+ no_such_device = ENODEV,
+ no_such_file_or_directory = ENOENT,
+ no_such_process = ESRCH,
+ not_a_directory = ENOTDIR,
+ not_a_socket = ENOTSOCK,
+ // clang-format off
+ not_a_stream _LIBCPP_DEPRECATED =
+ _LIBCPP_SUPPRESS_DEPRECATED_ERRC_PUSH
+#ifdef ENOSTR
+ ENOSTR
+#else
+ EINVAL
+#endif
+ _LIBCPP_SUPPRESS_DEPRECATED_ERRC_POP
+ ,
+ // clang-format on
+ not_connected = ENOTCONN,
+ not_enough_memory = ENOMEM,
+ not_supported = ENOTSUP,
+ operation_canceled = ECANCELED,
+ operation_in_progress = EINPROGRESS,
+ operation_not_permitted = EPERM,
+ operation_not_supported = EOPNOTSUPP,
+ operation_would_block = EWOULDBLOCK,
+ owner_dead = EOWNERDEAD,
+ permission_denied = EACCES,
+ protocol_error = EPROTO,
+ protocol_not_supported = EPROTONOSUPPORT,
+ read_only_file_system = EROFS,
+ resource_deadlock_would_occur = EDEADLK,
+ resource_unavailable_try_again = EAGAIN,
+ result_out_of_range = ERANGE,
+ state_not_recoverable = ENOTRECOVERABLE,
+ // clang-format off
+ stream_timeout _LIBCPP_DEPRECATED =
+ _LIBCPP_SUPPRESS_DEPRECATED_ERRC_PUSH
+#ifdef ETIME
+ ETIME
+#else
+ ETIMEDOUT
+#endif
+ _LIBCPP_SUPPRESS_DEPRECATED_ERRC_POP
+ ,
+ // clang-format on
+ text_file_busy = ETXTBSY,
+ timed_out = ETIMEDOUT,
+ too_many_files_open_in_system = ENFILE,
+ too_many_files_open = EMFILE,
+ too_many_links = EMLINK,
+ too_many_symbolic_link_levels = ELOOP,
+ value_too_large = EOVERFLOW,
+ wrong_protocol_type = EPROTOTYPE};
+_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(errc)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ERRC
diff --git a/libcxx/include/__cxx03/__system_error/error_category.h b/libcxx/include/__cxx03/__system_error/error_category.h
new file mode 100644
index 00000000000000..bfe7bc24a5d3dc
--- /dev/null
+++ b/libcxx/include/__cxx03/__system_error/error_category.h
@@ -0,0 +1,75 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SYSTEM_ERROR_ERROR_CATEGORY_H
+#define _LIBCPP___SYSTEM_ERROR_ERROR_CATEGORY_H
+
+#include <__compare/ordering.h>
+#include <__config>
+#include <string>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_EXPORTED_FROM_ABI error_condition;
+class _LIBCPP_EXPORTED_FROM_ABI error_code;
+
+class _LIBCPP_HIDDEN __do_message;
+
+class _LIBCPP_EXPORTED_FROM_ABI error_category {
+public:
+ virtual ~error_category() _NOEXCEPT;
+
+#if defined(_LIBCPP_ERROR_CATEGORY_DEFINE_LEGACY_INLINE_FUNCTIONS)
+ error_category() noexcept;
+#else
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 error_category() _NOEXCEPT = default;
+#endif
+ error_category(const error_category&) = delete;
+ error_category& operator=(const error_category&) = delete;
+
+ virtual const char* name() const _NOEXCEPT = 0;
+ virtual error_condition default_error_condition(int __ev) const _NOEXCEPT;
+ virtual bool equivalent(int __code, const error_condition& __condition) const _NOEXCEPT;
+ virtual bool equivalent(const error_code& __code, int __condition) const _NOEXCEPT;
+ virtual string message(int __ev) const = 0;
+
+ _LIBCPP_HIDE_FROM_ABI bool operator==(const error_category& __rhs) const _NOEXCEPT { return this == &__rhs; }
+
+#if _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(const error_category& __rhs) const noexcept {
+ return compare_three_way()(this, std::addressof(__rhs));
+ }
+
+#else // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(const error_category& __rhs) const _NOEXCEPT { return !(*this == __rhs); }
+
+ _LIBCPP_HIDE_FROM_ABI bool operator<(const error_category& __rhs) const _NOEXCEPT { return this < &__rhs; }
+
+#endif // _LIBCPP_STD_VER >= 20
+
+ friend class _LIBCPP_HIDDEN __do_message;
+};
+
+class _LIBCPP_HIDDEN __do_message : public error_category {
+public:
+ string message(int __ev) const override;
+};
+
+__attribute__((__const__)) _LIBCPP_EXPORTED_FROM_ABI const error_category& generic_category() _NOEXCEPT;
+__attribute__((__const__)) _LIBCPP_EXPORTED_FROM_ABI const error_category& system_category() _NOEXCEPT;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___SYSTEM_ERROR_ERROR_CATEGORY_H
diff --git a/libcxx/include/__cxx03/__system_error/error_code.h b/libcxx/include/__cxx03/__system_error/error_code.h
new file mode 100644
index 00000000000000..475f2bb96a56d9
--- /dev/null
+++ b/libcxx/include/__cxx03/__system_error/error_code.h
@@ -0,0 +1,143 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SYSTEM_ERROR_ERROR_CODE_H
+#define _LIBCPP___SYSTEM_ERROR_ERROR_CODE_H
+
+#include <__compare/ordering.h>
+#include <__config>
+#include <__functional/hash.h>
+#include <__functional/unary_function.h>
+#include <__system_error/errc.h>
+#include <__system_error/error_category.h>
+#include <__system_error/error_condition.h>
+#include <cstddef>
+#include <string>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_error_code_enum : public false_type {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_error_code_enum_v = is_error_code_enum<_Tp>::value;
+#endif
+
+namespace __adl_only {
+// Those cause ADL to trigger but they are not viable candidates,
+// so they are never actually selected.
+void make_error_code() = delete;
+} // namespace __adl_only
+
+class _LIBCPP_EXPORTED_FROM_ABI error_code {
+ int __val_;
+ const error_category* __cat_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI error_code() _NOEXCEPT : __val_(0), __cat_(&system_category()) {}
+
+ _LIBCPP_HIDE_FROM_ABI error_code(int __val, const error_category& __cat) _NOEXCEPT : __val_(__val), __cat_(&__cat) {}
+
+ template <class _Ep, __enable_if_t<is_error_code_enum<_Ep>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI error_code(_Ep __e) _NOEXCEPT {
+ using __adl_only::make_error_code;
+ *this = make_error_code(__e);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void assign(int __val, const error_category& __cat) _NOEXCEPT {
+ __val_ = __val;
+ __cat_ = &__cat;
+ }
+
+ template <class _Ep, __enable_if_t<is_error_code_enum<_Ep>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI error_code& operator=(_Ep __e) _NOEXCEPT {
+ using __adl_only::make_error_code;
+ *this = make_error_code(__e);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT {
+ __val_ = 0;
+ __cat_ = &system_category();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int value() const _NOEXCEPT { return __val_; }
+
+ _LIBCPP_HIDE_FROM_ABI const error_category& category() const _NOEXCEPT { return *__cat_; }
+
+ _LIBCPP_HIDE_FROM_ABI error_condition default_error_condition() const _NOEXCEPT {
+ return __cat_->default_error_condition(__val_);
+ }
+
+ string message() const;
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return __val_ != 0; }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI error_code make_error_code(errc __e) _NOEXCEPT {
+ return error_code(static_cast<int>(__e), generic_category());
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const error_code& __x, const error_code& __y) _NOEXCEPT {
+ return __x.category() == __y.category() && __x.value() == __y.value();
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const error_code& __x, const error_condition& __y) _NOEXCEPT {
+ return __x.category().equivalent(__x.value(), __y) || __y.category().equivalent(__x, __y.value());
+}
+
+#if _LIBCPP_STD_VER <= 17
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const error_condition& __x, const error_code& __y) _NOEXCEPT {
+ return __y == __x;
+}
+#endif
+
+#if _LIBCPP_STD_VER <= 17
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const error_code& __x, const error_code& __y) _NOEXCEPT {
+ return !(__x == __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const error_code& __x, const error_condition& __y) _NOEXCEPT {
+ return !(__x == __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const error_condition& __x, const error_code& __y) _NOEXCEPT {
+ return !(__x == __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const error_code& __x, const error_code& __y) _NOEXCEPT {
+ return __x.category() < __y.category() || (__x.category() == __y.category() && __x.value() < __y.value());
+}
+
+#else // _LIBCPP_STD_VER <= 17
+
+inline _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(const error_code& __x, const error_code& __y) noexcept {
+ if (auto __c = __x.category() <=> __y.category(); __c != 0)
+ return __c;
+ return __x.value() <=> __y.value();
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<error_code> : public __unary_function<error_code, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const error_code& __ec) const _NOEXCEPT {
+ return static_cast<size_t>(__ec.value());
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___SYSTEM_ERROR_ERROR_CODE_H
diff --git a/libcxx/include/__cxx03/__system_error/error_condition.h b/libcxx/include/__cxx03/__system_error/error_condition.h
new file mode 100644
index 00000000000000..42898c1f0e9013
--- /dev/null
+++ b/libcxx/include/__cxx03/__system_error/error_condition.h
@@ -0,0 +1,130 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SYSTEM_ERROR_ERROR_CONDITION_H
+#define _LIBCPP___SYSTEM_ERROR_ERROR_CONDITION_H
+
+#include <__compare/ordering.h>
+#include <__config>
+#include <__functional/hash.h>
+#include <__functional/unary_function.h>
+#include <__system_error/errc.h>
+#include <__system_error/error_category.h>
+#include <cstddef>
+#include <string>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum : public false_type {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_error_condition_enum_v = is_error_condition_enum<_Tp>::value;
+#endif
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum<errc> : true_type {};
+
+#ifdef _LIBCPP_CXX03_LANG
+template <>
+struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum<errc::__lx> : true_type {};
+#endif
+
+namespace __adl_only {
+// Those cause ADL to trigger but they are not viable candidates,
+// so they are never actually selected.
+void make_error_condition() = delete;
+} // namespace __adl_only
+
+class _LIBCPP_EXPORTED_FROM_ABI error_condition {
+ int __val_;
+ const error_category* __cat_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI error_condition() _NOEXCEPT : __val_(0), __cat_(&generic_category()) {}
+
+ _LIBCPP_HIDE_FROM_ABI error_condition(int __val, const error_category& __cat) _NOEXCEPT
+ : __val_(__val),
+ __cat_(&__cat) {}
+
+ template <class _Ep, __enable_if_t<is_error_condition_enum<_Ep>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI error_condition(_Ep __e) _NOEXCEPT {
+ using __adl_only::make_error_condition;
+ *this = make_error_condition(__e);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void assign(int __val, const error_category& __cat) _NOEXCEPT {
+ __val_ = __val;
+ __cat_ = &__cat;
+ }
+
+ template <class _Ep, __enable_if_t<is_error_condition_enum<_Ep>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI error_condition& operator=(_Ep __e) _NOEXCEPT {
+ using __adl_only::make_error_condition;
+ *this = make_error_condition(__e);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT {
+ __val_ = 0;
+ __cat_ = &generic_category();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI int value() const _NOEXCEPT { return __val_; }
+
+ _LIBCPP_HIDE_FROM_ABI const error_category& category() const _NOEXCEPT { return *__cat_; }
+ string message() const;
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return __val_ != 0; }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI error_condition make_error_condition(errc __e) _NOEXCEPT {
+ return error_condition(static_cast<int>(__e), generic_category());
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const error_condition& __x, const error_condition& __y) _NOEXCEPT {
+ return __x.category() == __y.category() && __x.value() == __y.value();
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const error_condition& __x, const error_condition& __y) _NOEXCEPT {
+ return !(__x == __y);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const error_condition& __x, const error_condition& __y) _NOEXCEPT {
+ return __x.category() < __y.category() || (__x.category() == __y.category() && __x.value() < __y.value());
+}
+
+#else // _LIBCPP_STD_VER <= 17
+
+inline _LIBCPP_HIDE_FROM_ABI strong_ordering
+operator<=>(const error_condition& __x, const error_condition& __y) noexcept {
+ if (auto __c = __x.category() <=> __y.category(); __c != 0)
+ return __c;
+ return __x.value() <=> __y.value();
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<error_condition> : public __unary_function<error_condition, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const error_condition& __ec) const _NOEXCEPT {
+ return static_cast<size_t>(__ec.value());
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___SYSTEM_ERROR_ERROR_CONDITION_H
diff --git a/libcxx/include/__cxx03/__system_error/system_error.h b/libcxx/include/__cxx03/__system_error/system_error.h
new file mode 100644
index 00000000000000..362e67505658cb
--- /dev/null
+++ b/libcxx/include/__cxx03/__system_error/system_error.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___SYSTEM_ERROR_SYSTEM_ERROR_H
+#define _LIBCPP___SYSTEM_ERROR_SYSTEM_ERROR_H
+
+#include <__config>
+#include <__system_error/error_category.h>
+#include <__system_error/error_code.h>
+#include <__verbose_abort>
+#include <stdexcept>
+#include <string>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_EXPORTED_FROM_ABI system_error : public runtime_error {
+ error_code __ec_;
+
+public:
+ system_error(error_code __ec, const string& __what_arg);
+ system_error(error_code __ec, const char* __what_arg);
+ system_error(error_code __ec);
+ system_error(int __ev, const error_category& __ecat, const string& __what_arg);
+ system_error(int __ev, const error_category& __ecat, const char* __what_arg);
+ system_error(int __ev, const error_category& __ecat);
+ _LIBCPP_HIDE_FROM_ABI system_error(const system_error&) _NOEXCEPT = default;
+ ~system_error() _NOEXCEPT override;
+
+ _LIBCPP_HIDE_FROM_ABI const error_code& code() const _NOEXCEPT { return __ec_; }
+};
+
+_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void __throw_system_error(int __ev, const char* __what_arg);
+_LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI inline void __throw_system_error(error_code __ec, const char* __what_arg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw system_error(__ec, __what_arg);
+#else
+ _LIBCPP_VERBOSE_ABORT(
+ "system_error was thrown in -fno-exceptions mode with error %i and message \"%s\"", __ec.value(), __what_arg);
+#endif
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___SYSTEM_ERROR_SYSTEM_ERROR_H
diff --git a/libcxx/include/__cxx03/__thread/formatter.h b/libcxx/include/__cxx03/__thread/formatter.h
new file mode 100644
index 00000000000000..9b54036dcab36b
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/formatter.h
@@ -0,0 +1,80 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_FORMATTER_H
+#define _LIBCPP___THREAD_FORMATTER_H
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__format/concepts.h>
+#include <__format/format_parse_context.h>
+#include <__format/formatter.h>
+#include <__format/formatter_integral.h>
+#include <__format/parser_std_format_spec.h>
+#include <__thread/id.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# ifndef _LIBCPP_HAS_NO_THREADS
+
+template <__fmt_char_type _CharT>
+struct _LIBCPP_TEMPLATE_VIS formatter<__thread_id, _CharT> {
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return __parser_.__parse(__ctx, __format_spec::__fields_fill_align_width);
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(__thread_id __id, _FormatContext& __ctx) const {
+ // In __thread/support/pthread.h, __libcpp_thread_id is either a
+ // unsigned long long or a pthread_t.
+ //
+ // The type of pthread_t is left unspecified in POSIX so it can be any
+ // type. The most logical types are an integral or pointer.
+ // On Linux systems pthread_t is an unsigned long long.
+ // On Apple systems pthread_t is a pointer type.
+ //
+ // Note the output should match what the stream operator does. Since
+ // the ostream operator has been shipped years before this formatter
+ // was added to the Standard, this formatter does what the stream
+ // operator does. This may require platform specific changes.
+
+ using _Tp = decltype(__get_underlying_id(__id));
+ using _Cp = conditional_t<integral<_Tp>, _Tp, conditional_t<is_pointer_v<_Tp>, uintptr_t, void>>;
+ static_assert(!is_same_v<_Cp, void>, "unsupported thread::id type, please file a bug report");
+
+ __format_spec::__parsed_specifications<_CharT> __specs = __parser_.__get_parsed_std_specifications(__ctx);
+ if constexpr (is_pointer_v<_Tp>) {
+ __specs.__std_.__alternate_form_ = true;
+ __specs.__std_.__type_ = __format_spec::__type::__hexadecimal_lower_case;
+ }
+ return __formatter::__format_integer(reinterpret_cast<_Cp>(__get_underlying_id(__id)), __ctx, __specs);
+ }
+
+ __format_spec::__parser<_CharT> __parser_{.__alignment_ = __format_spec::__alignment::__right};
+};
+
+# endif // !_LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+#endif // _LIBCPP___THREAD_FORMATTER_H
diff --git a/libcxx/include/__cxx03/__thread/id.h b/libcxx/include/__cxx03/__thread/id.h
new file mode 100644
index 00000000000000..6db0ccbfe569b6
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/id.h
@@ -0,0 +1,121 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_ID_H
+#define _LIBCPP___THREAD_ID_H
+
+#include <__compare/ordering.h>
+#include <__config>
+#include <__fwd/functional.h>
+#include <__fwd/ostream.h>
+#include <__thread/support.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+class _LIBCPP_EXPORTED_FROM_ABI __thread_id;
+
+namespace this_thread {
+
+_LIBCPP_HIDE_FROM_ABI __thread_id get_id() _NOEXCEPT;
+
+} // namespace this_thread
+
+template <>
+struct hash<__thread_id>;
+
+class _LIBCPP_TEMPLATE_VIS __thread_id {
+ // FIXME: pthread_t is a pointer on Darwin but a long on Linux.
+ // NULL is the no-thread value on Darwin. Someone needs to check
+ // on other platforms. We assume 0 works everywhere for now.
+ __libcpp_thread_id __id_;
+
+ static _LIBCPP_HIDE_FROM_ABI bool
+ __lt_impl(__thread_id __x, __thread_id __y) _NOEXCEPT { // id==0 is always less than any other thread_id
+ if (__x.__id_ == 0)
+ return __y.__id_ != 0;
+ if (__y.__id_ == 0)
+ return false;
+ return __libcpp_thread_id_less(__x.__id_, __y.__id_);
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __thread_id() _NOEXCEPT : __id_(0) {}
+
+ _LIBCPP_HIDE_FROM_ABI void __reset() { __id_ = 0; }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT;
+# if _LIBCPP_STD_VER <= 17
+ friend _LIBCPP_HIDE_FROM_ABI bool operator<(__thread_id __x, __thread_id __y) _NOEXCEPT;
+# else // _LIBCPP_STD_VER <= 17
+ friend _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(__thread_id __x, __thread_id __y) noexcept;
+# endif // _LIBCPP_STD_VER <= 17
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id);
+
+private:
+ _LIBCPP_HIDE_FROM_ABI __thread_id(__libcpp_thread_id __id) : __id_(__id) {}
+
+ _LIBCPP_HIDE_FROM_ABI friend __libcpp_thread_id __get_underlying_id(const __thread_id __id) { return __id.__id_; }
+
+ friend __thread_id this_thread::get_id() _NOEXCEPT;
+ friend class _LIBCPP_EXPORTED_FROM_ABI thread;
+ friend struct _LIBCPP_TEMPLATE_VIS hash<__thread_id>;
+};
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT {
+ // Don't pass id==0 to underlying routines
+ if (__x.__id_ == 0)
+ return __y.__id_ == 0;
+ if (__y.__id_ == 0)
+ return false;
+ return __libcpp_thread_id_equal(__x.__id_, __y.__id_);
+}
+
+# if _LIBCPP_STD_VER <= 17
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(__thread_id __x, __thread_id __y) _NOEXCEPT { return !(__x == __y); }
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(__thread_id __x, __thread_id __y) _NOEXCEPT {
+ return __thread_id::__lt_impl(__x.__id_, __y.__id_);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(__thread_id __x, __thread_id __y) _NOEXCEPT { return !(__y < __x); }
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(__thread_id __x, __thread_id __y) _NOEXCEPT { return __y < __x; }
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(__thread_id __x, __thread_id __y) _NOEXCEPT { return !(__x < __y); }
+
+# else // _LIBCPP_STD_VER <= 17
+
+inline _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(__thread_id __x, __thread_id __y) noexcept {
+ if (__x == __y)
+ return strong_ordering::equal;
+ if (__thread_id::__lt_impl(__x, __y))
+ return strong_ordering::less;
+ return strong_ordering::greater;
+}
+
+# endif // _LIBCPP_STD_VER <= 17
+
+namespace this_thread {
+
+inline _LIBCPP_HIDE_FROM_ABI __thread_id get_id() _NOEXCEPT { return __libcpp_thread_get_current_id(); }
+
+} // namespace this_thread
+
+#endif // !_LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___THREAD_ID_H
diff --git a/libcxx/include/__cxx03/__thread/jthread.h b/libcxx/include/__cxx03/__thread/jthread.h
new file mode 100644
index 00000000000000..b3d5c25fb71c77
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/jthread.h
@@ -0,0 +1,134 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_JTHREAD_H
+#define _LIBCPP___THREAD_JTHREAD_H
+
+#include <__config>
+#include <__functional/invoke.h>
+#include <__stop_token/stop_source.h>
+#include <__stop_token/stop_token.h>
+#include <__thread/support.h>
+#include <__thread/thread.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN)
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_AVAILABILITY_SYNC jthread {
+public:
+ // types
+ using id = thread::id;
+ using native_handle_type = thread::native_handle_type;
+
+ // [thread.jthread.cons], constructors, move, and assignment
+ _LIBCPP_HIDE_FROM_ABI jthread() noexcept : __stop_source_(std::nostopstate) {}
+
+ template <class _Fun, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI explicit jthread(_Fun&& __fun, _Args&&... __args)
+ requires(!std::is_same_v<remove_cvref_t<_Fun>, jthread>)
+ : __stop_source_(),
+ __thread_(__init_thread(__stop_source_, std::forward<_Fun>(__fun), std::forward<_Args>(__args)...)) {
+ static_assert(is_constructible_v<decay_t<_Fun>, _Fun>);
+ static_assert((is_constructible_v<decay_t<_Args>, _Args> && ...));
+ static_assert(is_invocable_v<decay_t<_Fun>, decay_t<_Args>...> ||
+ is_invocable_v<decay_t<_Fun>, stop_token, decay_t<_Args>...>);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~jthread() {
+ if (joinable()) {
+ request_stop();
+ join();
+ }
+ }
+
+ jthread(const jthread&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI jthread(jthread&&) noexcept = default;
+
+ jthread& operator=(const jthread&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI jthread& operator=(jthread&& __other) noexcept {
+ if (this != &__other) {
+ if (joinable()) {
+ request_stop();
+ join();
+ }
+ __stop_source_ = std::move(__other.__stop_source_);
+ __thread_ = std::move(__other.__thread_);
+ }
+
+ return *this;
+ }
+
+ // [thread.jthread.mem], members
+ _LIBCPP_HIDE_FROM_ABI void swap(jthread& __other) noexcept {
+ std::swap(__stop_source_, __other.__stop_source_);
+ std::swap(__thread_, __other.__thread_);
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool joinable() const noexcept { return get_id() != id(); }
+
+ _LIBCPP_HIDE_FROM_ABI void join() { __thread_.join(); }
+
+ _LIBCPP_HIDE_FROM_ABI void detach() { __thread_.detach(); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI id get_id() const noexcept { return __thread_.get_id(); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() { return __thread_.native_handle(); }
+
+ // [thread.jthread.stop], stop token handling
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI stop_source get_stop_source() noexcept { return __stop_source_; }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI stop_token get_stop_token() const noexcept { return __stop_source_.get_token(); }
+
+ _LIBCPP_HIDE_FROM_ABI bool request_stop() noexcept { return __stop_source_.request_stop(); }
+
+ // [thread.jthread.special], specialized algorithms
+ _LIBCPP_HIDE_FROM_ABI friend void swap(jthread& __lhs, jthread& __rhs) noexcept { __lhs.swap(__rhs); }
+
+ // [thread.jthread.static], static members
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static unsigned int hardware_concurrency() noexcept {
+ return thread::hardware_concurrency();
+ }
+
+private:
+ template <class _Fun, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI static thread __init_thread(const stop_source& __ss, _Fun&& __fun, _Args&&... __args) {
+ if constexpr (is_invocable_v<decay_t<_Fun>, stop_token, decay_t<_Args>...>) {
+ return thread(std::forward<_Fun>(__fun), __ss.get_token(), std::forward<_Args>(__args)...);
+ } else {
+ return thread(std::forward<_Fun>(__fun), std::forward<_Args>(__args)...);
+ }
+ }
+
+ stop_source __stop_source_;
+ thread __thread_;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN)
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___THREAD_JTHREAD_H
diff --git a/libcxx/include/__cxx03/__thread/poll_with_backoff.h b/libcxx/include/__cxx03/__thread/poll_with_backoff.h
new file mode 100644
index 00000000000000..4f961fe3f7629f
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/poll_with_backoff.h
@@ -0,0 +1,67 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_POLL_WITH_BACKOFF_H
+#define _LIBCPP___THREAD_POLL_WITH_BACKOFF_H
+
+#include <__chrono/duration.h>
+#include <__chrono/high_resolution_clock.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+static _LIBCPP_CONSTEXPR const int __libcpp_polling_count = 64;
+
+// Polls a thread for a condition given by a predicate, and backs off based on a backoff policy
+// before polling again.
+//
+// - __poll is the "test function" that should return true if polling succeeded, and false if it failed.
+//
+// - __backoff is the "backoff policy", which is called with the duration since we started polling. It should
+// return false in order to resume polling, and true if polling should stop entirely for some reason.
+// In general, backoff policies sleep for some time before returning control to the polling loop.
+//
+// - __max_elapsed is the maximum duration to try polling for. If the maximum duration is exceeded,
+// the polling loop will return false to report a timeout.
+template <class _Poll, class _Backoff>
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool __libcpp_thread_poll_with_backoff(
+ _Poll&& __poll, _Backoff&& __backoff, chrono::nanoseconds __max_elapsed = chrono::nanoseconds::zero()) {
+ auto const __start = chrono::high_resolution_clock::now();
+ for (int __count = 0;;) {
+ if (__poll())
+ return true; // __poll completion means success
+ if (__count < __libcpp_polling_count) {
+ __count += 1;
+ continue;
+ }
+ chrono::nanoseconds const __elapsed = chrono::high_resolution_clock::now() - __start;
+ if (__max_elapsed != chrono::nanoseconds::zero() && __max_elapsed < __elapsed)
+ return false; // timeout failure
+ if (__backoff(__elapsed))
+ return false; // __backoff completion means failure
+ }
+}
+
+// A trivial backoff policy that always immediately returns the control to
+// the polling loop.
+//
+// This is not very well-behaved since it will cause the polling loop to spin,
+// so this should most likely only be used on single-threaded systems where there
+// are no other threads to compete with.
+struct __spinning_backoff_policy {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool operator()(chrono::nanoseconds const&) const { return false; }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___THREAD_POLL_WITH_BACKOFF_H
diff --git a/libcxx/include/__cxx03/__thread/support.h b/libcxx/include/__cxx03/__thread/support.h
new file mode 100644
index 00000000000000..92f1c4415e4dfa
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/support.h
@@ -0,0 +1,123 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_SUPPORT_H
+#define _LIBCPP___THREAD_SUPPORT_H
+
+#include <__config>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+/*
+
+//
+// The library supports multiple implementations of the basic threading functionality.
+// The following functionality must be provided by any implementation:
+//
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using __libcpp_timespec_t = ...;
+
+//
+// Mutex
+//
+using __libcpp_mutex_t = ...;
+#define _LIBCPP_MUTEX_INITIALIZER ...
+
+using __libcpp_recursive_mutex_t = ...;
+
+int __libcpp_recursive_mutex_init(__libcpp_recursive_mutex_t*);
+_LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_recursive_mutex_lock(__libcpp_recursive_mutex_t*);
+_LIBCPP_NO_THREAD_SAFETY_ANALYSIS bool __libcpp_recursive_mutex_trylock(__libcpp_recursive_mutex_t*);
+_LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_recursive_mutex_unlock(__libcpp_recursive_mutex_t*);
+int __libcpp_recursive_mutex_destroy(__libcpp_recursive_mutex_t*);
+
+_LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_mutex_lock(__libcpp_mutex_t*);
+_LIBCPP_NO_THREAD_SAFETY_ANALYSIS bool __libcpp_mutex_trylock(__libcpp_mutex_t*);
+_LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_mutex_unlock(__libcpp_mutex_t*);
+int __libcpp_mutex_destroy(__libcpp_mutex_t*);
+
+//
+// Condition Variable
+//
+using __libcpp_condvar_t = ...;
+#define _LIBCPP_CONDVAR_INITIALIZER ...
+
+int __libcpp_condvar_signal(__libcpp_condvar_t*);
+int __libcpp_condvar_broadcast(__libcpp_condvar_t*);
+_LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_condvar_wait(__libcpp_condvar_t*, __libcpp_mutex_t*);
+_LIBCPP_NO_THREAD_SAFETY_ANALYSIS
+int __libcpp_condvar_timedwait(__libcpp_condvar_t*, __libcpp_mutex_t*, __libcpp_timespec_t*);
+int __libcpp_condvar_destroy(__libcpp_condvar_t*);
+
+//
+// Execute once
+//
+using __libcpp_exec_once_flag = ...;
+#define _LIBCPP_EXEC_ONCE_INITIALIZER ...
+
+int __libcpp_execute_once(__libcpp_exec_once_flag*, void (*__init_routine)());
+
+//
+// Thread id
+//
+using __libcpp_thread_id = ...;
+
+bool __libcpp_thread_id_equal(__libcpp_thread_id, __libcpp_thread_id);
+bool __libcpp_thread_id_less(__libcpp_thread_id, __libcpp_thread_id);
+
+//
+// Thread
+//
+#define _LIBCPP_NULL_THREAD ...
+using __libcpp_thread_t = ...;
+
+bool __libcpp_thread_isnull(const __libcpp_thread_t*);
+int __libcpp_thread_create(__libcpp_thread_t*, void* (*__func)(void*), void* __arg);
+__libcpp_thread_id __libcpp_thread_get_current_id();
+__libcpp_thread_id __libcpp_thread_get_id(const __libcpp_thread_t*);
+int __libcpp_thread_join(__libcpp_thread_t*);
+int __libcpp_thread_detach(__libcpp_thread_t*);
+void __libcpp_thread_yield();
+void __libcpp_thread_sleep_for(const chrono::nanoseconds&);
+
+//
+// Thread local storage
+//
+#define _LIBCPP_TLS_DESTRUCTOR_CC ...
+using __libcpp_tls_key = ...;
+
+int __libcpp_tls_create(__libcpp_tls_key*, void (*__at_exit)(void*));
+void* __libcpp_tls_get(__libcpp_tls_key);
+int __libcpp_tls_set(__libcpp_tls_key, void*);
+
+_LIBCPP_END_NAMESPACE_STD
+
+*/
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+# if defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
+# include <__thread/support/external.h>
+# elif defined(_LIBCPP_HAS_THREAD_API_PTHREAD)
+# include <__thread/support/pthread.h>
+# elif defined(_LIBCPP_HAS_THREAD_API_C11)
+# include <__thread/support/c11.h>
+# elif defined(_LIBCPP_HAS_THREAD_API_WIN32)
+# include <__thread/support/windows.h>
+# else
+# error "No threading API was selected"
+# endif
+
+#endif // !_LIBCPP_HAS_NO_THREADS
+
+#endif // _LIBCPP___THREAD_SUPPORT_H
diff --git a/libcxx/include/__cxx03/__thread/support/c11.h b/libcxx/include/__cxx03/__thread/support/c11.h
new file mode 100644
index 00000000000000..fe00a2d97fadc0
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/support/c11.h
@@ -0,0 +1,191 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_SUPPORT_C11_H
+#define _LIBCPP___THREAD_SUPPORT_C11_H
+
+#include <__chrono/convert_to_timespec.h>
+#include <__chrono/duration.h>
+#include <__config>
+#include <ctime>
+#include <errno.h>
+#include <threads.h>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using __libcpp_timespec_t = ::timespec;
+
+//
+// Mutex
+//
+typedef mtx_t __libcpp_mutex_t;
+// mtx_t is a struct so using {} for initialization is valid.
+#define _LIBCPP_MUTEX_INITIALIZER \
+ {}
+
+typedef mtx_t __libcpp_recursive_mutex_t;
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_recursive_mutex_init(__libcpp_recursive_mutex_t* __m) {
+ return mtx_init(__m, mtx_plain | mtx_recursive) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_recursive_mutex_lock(__libcpp_recursive_mutex_t* __m) {
+ return mtx_lock(__m) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS bool
+__libcpp_recursive_mutex_trylock(__libcpp_recursive_mutex_t* __m) {
+ return mtx_trylock(__m) == thrd_success;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_recursive_mutex_unlock(__libcpp_recursive_mutex_t* __m) {
+ return mtx_unlock(__m) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_recursive_mutex_destroy(__libcpp_recursive_mutex_t* __m) {
+ mtx_destroy(__m);
+ return 0;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_mutex_lock(__libcpp_mutex_t* __m) {
+ return mtx_lock(__m) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS bool __libcpp_mutex_trylock(__libcpp_mutex_t* __m) {
+ return mtx_trylock(__m) == thrd_success;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_mutex_unlock(__libcpp_mutex_t* __m) {
+ return mtx_unlock(__m) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_mutex_destroy(__libcpp_mutex_t* __m) {
+ mtx_destroy(__m);
+ return 0;
+}
+
+//
+// Condition Variable
+//
+typedef cnd_t __libcpp_condvar_t;
+// cnd_t is a struct so using {} for initialization is valid.
+#define _LIBCPP_CONDVAR_INITIALIZER \
+ {}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_condvar_signal(__libcpp_condvar_t* __cv) {
+ return cnd_signal(__cv) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_condvar_broadcast(__libcpp_condvar_t* __cv) {
+ return cnd_broadcast(__cv) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_condvar_wait(__libcpp_condvar_t* __cv, __libcpp_mutex_t* __m) {
+ return cnd_wait(__cv, __m) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_condvar_timedwait(__libcpp_condvar_t* __cv, __libcpp_mutex_t* __m, timespec* __ts) {
+ int __ec = cnd_timedwait(__cv, __m, __ts);
+ return __ec == thrd_timedout ? ETIMEDOUT : __ec;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_condvar_destroy(__libcpp_condvar_t* __cv) {
+ cnd_destroy(__cv);
+ return 0;
+}
+
+//
+// Execute once
+//
+typedef ::once_flag __libcpp_exec_once_flag;
+#define _LIBCPP_EXEC_ONCE_INITIALIZER ONCE_FLAG_INIT
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_execute_once(__libcpp_exec_once_flag* flag, void (*init_routine)(void)) {
+ ::call_once(flag, init_routine);
+ return 0;
+}
+
+//
+// Thread id
+//
+typedef thrd_t __libcpp_thread_id;
+
+// Returns non-zero if the thread ids are equal, otherwise 0
+inline _LIBCPP_HIDE_FROM_ABI bool __libcpp_thread_id_equal(__libcpp_thread_id t1, __libcpp_thread_id t2) {
+ return thrd_equal(t1, t2) != 0;
+}
+
+// Returns non-zero if t1 < t2, otherwise 0
+inline _LIBCPP_HIDE_FROM_ABI bool __libcpp_thread_id_less(__libcpp_thread_id t1, __libcpp_thread_id t2) {
+ return t1 < t2;
+}
+
+//
+// Thread
+//
+#define _LIBCPP_NULL_THREAD 0U
+
+typedef thrd_t __libcpp_thread_t;
+
+inline _LIBCPP_HIDE_FROM_ABI __libcpp_thread_id __libcpp_thread_get_id(const __libcpp_thread_t* __t) { return *__t; }
+
+inline _LIBCPP_HIDE_FROM_ABI bool __libcpp_thread_isnull(const __libcpp_thread_t* __t) {
+ return __libcpp_thread_get_id(__t) == 0;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_thread_create(__libcpp_thread_t* __t, void* (*__func)(void*), void* __arg) {
+ int __ec = thrd_create(__t, reinterpret_cast<thrd_start_t>(__func), __arg);
+ return __ec == thrd_nomem ? ENOMEM : __ec;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI __libcpp_thread_id __libcpp_thread_get_current_id() { return thrd_current(); }
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_thread_join(__libcpp_thread_t* __t) {
+ return thrd_join(*__t, nullptr) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_thread_detach(__libcpp_thread_t* __t) {
+ return thrd_detach(*__t) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void __libcpp_thread_yield() { thrd_yield(); }
+
+inline _LIBCPP_HIDE_FROM_ABI void __libcpp_thread_sleep_for(const chrono::nanoseconds& __ns) {
+ __libcpp_timespec_t __ts = std::__convert_to_timespec<__libcpp_timespec_t>(__ns);
+ thrd_sleep(&__ts, nullptr);
+}
+
+//
+// Thread local storage
+//
+#define _LIBCPP_TLS_DESTRUCTOR_CC /* nothing */
+
+typedef tss_t __libcpp_tls_key;
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_tls_create(__libcpp_tls_key* __key, void (*__at_exit)(void*)) {
+ return tss_create(__key, __at_exit) == thrd_success ? 0 : EINVAL;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void* __libcpp_tls_get(__libcpp_tls_key __key) { return tss_get(__key); }
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_tls_set(__libcpp_tls_key __key, void* __p) {
+ return tss_set(__key, __p) == thrd_success ? 0 : EINVAL;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___THREAD_SUPPORT_C11_H
diff --git a/libcxx/include/__cxx03/__thread/support/external.h b/libcxx/include/__cxx03/__thread/support/external.h
new file mode 100644
index 00000000000000..d5e212491cfdbd
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/support/external.h
@@ -0,0 +1,21 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_SUPPORT_EXTERNAL_H
+#define _LIBCPP___THREAD_SUPPORT_EXTERNAL_H
+
+#include <__config>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+#include <__external_threading>
+
+#endif // _LIBCPP___THREAD_SUPPORT_EXTERNAL_H
diff --git a/libcxx/include/__cxx03/__thread/support/pthread.h b/libcxx/include/__cxx03/__thread/support/pthread.h
new file mode 100644
index 00000000000000..531f3e71de8397
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/support/pthread.h
@@ -0,0 +1,221 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_SUPPORT_PTHREAD_H
+#define _LIBCPP___THREAD_SUPPORT_PTHREAD_H
+
+#include <__chrono/convert_to_timespec.h>
+#include <__chrono/duration.h>
+#include <__config>
+#include <ctime>
+#include <errno.h>
+#include <pthread.h>
+#include <sched.h>
+
+#ifdef __MVS__
+# include <__support/ibm/nanosleep.h>
+#endif
+
+// Some platforms require <bits/atomic_wide_counter.h> in order for
+// PTHREAD_COND_INITIALIZER to be expanded. Normally that would come
+// in via <pthread.h>, but it's a non-modular header on those platforms,
+// so libc++'s <math.h> usually absorbs atomic_wide_counter.h into the
+// module with <math.h> and makes atomic_wide_counter.h invisible.
+// Include <math.h> here to work around that.
+// This checks wheter a Clang module is built
+#if __building_module(std)
+# include <math.h>
+#endif
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using __libcpp_timespec_t = ::timespec;
+
+//
+// Mutex
+//
+typedef pthread_mutex_t __libcpp_mutex_t;
+#define _LIBCPP_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER
+
+typedef pthread_mutex_t __libcpp_recursive_mutex_t;
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_recursive_mutex_init(__libcpp_recursive_mutex_t* __m) {
+ pthread_mutexattr_t __attr;
+ int __ec = pthread_mutexattr_init(&__attr);
+ if (__ec)
+ return __ec;
+ __ec = pthread_mutexattr_settype(&__attr, PTHREAD_MUTEX_RECURSIVE);
+ if (__ec) {
+ pthread_mutexattr_destroy(&__attr);
+ return __ec;
+ }
+ __ec = pthread_mutex_init(__m, &__attr);
+ if (__ec) {
+ pthread_mutexattr_destroy(&__attr);
+ return __ec;
+ }
+ __ec = pthread_mutexattr_destroy(&__attr);
+ if (__ec) {
+ pthread_mutex_destroy(__m);
+ return __ec;
+ }
+ return 0;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_recursive_mutex_lock(__libcpp_recursive_mutex_t* __m) {
+ return pthread_mutex_lock(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS bool
+__libcpp_recursive_mutex_trylock(__libcpp_recursive_mutex_t* __m) {
+ return pthread_mutex_trylock(__m) == 0;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_recursive_mutex_unlock(__libcpp_recursive_mutex_t* __m) {
+ return pthread_mutex_unlock(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_recursive_mutex_destroy(__libcpp_recursive_mutex_t* __m) {
+ return pthread_mutex_destroy(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_mutex_lock(__libcpp_mutex_t* __m) {
+ return pthread_mutex_lock(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS bool __libcpp_mutex_trylock(__libcpp_mutex_t* __m) {
+ return pthread_mutex_trylock(__m) == 0;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_mutex_unlock(__libcpp_mutex_t* __m) {
+ return pthread_mutex_unlock(__m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_mutex_destroy(__libcpp_mutex_t* __m) { return pthread_mutex_destroy(__m); }
+
+//
+// Condition Variable
+//
+typedef pthread_cond_t __libcpp_condvar_t;
+#define _LIBCPP_CONDVAR_INITIALIZER PTHREAD_COND_INITIALIZER
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_condvar_signal(__libcpp_condvar_t* __cv) { return pthread_cond_signal(__cv); }
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_condvar_broadcast(__libcpp_condvar_t* __cv) {
+ return pthread_cond_broadcast(__cv);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_condvar_wait(__libcpp_condvar_t* __cv, __libcpp_mutex_t* __m) {
+ return pthread_cond_wait(__cv, __m);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_condvar_timedwait(__libcpp_condvar_t* __cv, __libcpp_mutex_t* __m, __libcpp_timespec_t* __ts) {
+ return pthread_cond_timedwait(__cv, __m, __ts);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_condvar_destroy(__libcpp_condvar_t* __cv) {
+ return pthread_cond_destroy(__cv);
+}
+
+//
+// Execute once
+//
+typedef pthread_once_t __libcpp_exec_once_flag;
+#define _LIBCPP_EXEC_ONCE_INITIALIZER PTHREAD_ONCE_INIT
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_execute_once(__libcpp_exec_once_flag* __flag, void (*__init_routine)()) {
+ return pthread_once(__flag, __init_routine);
+}
+
+//
+// Thread id
+//
+#if defined(__MVS__)
+typedef unsigned long long __libcpp_thread_id;
+#else
+typedef pthread_t __libcpp_thread_id;
+#endif
+
+// Returns non-zero if the thread ids are equal, otherwise 0
+inline _LIBCPP_HIDE_FROM_ABI bool __libcpp_thread_id_equal(__libcpp_thread_id __t1, __libcpp_thread_id __t2) {
+ return __t1 == __t2;
+}
+
+// Returns non-zero if t1 < t2, otherwise 0
+inline _LIBCPP_HIDE_FROM_ABI bool __libcpp_thread_id_less(__libcpp_thread_id __t1, __libcpp_thread_id __t2) {
+ return __t1 < __t2;
+}
+
+//
+// Thread
+//
+#define _LIBCPP_NULL_THREAD ((__libcpp_thread_t()))
+typedef pthread_t __libcpp_thread_t;
+
+inline _LIBCPP_HIDE_FROM_ABI __libcpp_thread_id __libcpp_thread_get_id(const __libcpp_thread_t* __t) {
+#if defined(__MVS__)
+ return __t->__;
+#else
+ return *__t;
+#endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool __libcpp_thread_isnull(const __libcpp_thread_t* __t) {
+ return __libcpp_thread_get_id(__t) == 0;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_thread_create(__libcpp_thread_t* __t, void* (*__func)(void*), void* __arg) {
+ return pthread_create(__t, nullptr, __func, __arg);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI __libcpp_thread_id __libcpp_thread_get_current_id() {
+ const __libcpp_thread_t __current_thread = pthread_self();
+ return __libcpp_thread_get_id(&__current_thread);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_thread_join(__libcpp_thread_t* __t) { return pthread_join(*__t, nullptr); }
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_thread_detach(__libcpp_thread_t* __t) { return pthread_detach(*__t); }
+
+inline _LIBCPP_HIDE_FROM_ABI void __libcpp_thread_yield() { sched_yield(); }
+
+inline _LIBCPP_HIDE_FROM_ABI void __libcpp_thread_sleep_for(const chrono::nanoseconds& __ns) {
+ __libcpp_timespec_t __ts = std::__convert_to_timespec<__libcpp_timespec_t>(__ns);
+ while (nanosleep(&__ts, &__ts) == -1 && errno == EINTR)
+ ;
+}
+
+//
+// Thread local storage
+//
+#define _LIBCPP_TLS_DESTRUCTOR_CC /* nothing */
+
+typedef pthread_key_t __libcpp_tls_key;
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_tls_create(__libcpp_tls_key* __key, void (*__at_exit)(void*)) {
+ return pthread_key_create(__key, __at_exit);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void* __libcpp_tls_get(__libcpp_tls_key __key) { return pthread_getspecific(__key); }
+
+inline _LIBCPP_HIDE_FROM_ABI int __libcpp_tls_set(__libcpp_tls_key __key, void* __p) {
+ return pthread_setspecific(__key, __p);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___THREAD_SUPPORT_PTHREAD_H
diff --git a/libcxx/include/__cxx03/__thread/support/windows.h b/libcxx/include/__cxx03/__thread/support/windows.h
new file mode 100644
index 00000000000000..5dc4fa14f45b6b
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/support/windows.h
@@ -0,0 +1,133 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_SUPPORT_WINDOWS_H
+#define _LIBCPP___THREAD_SUPPORT_WINDOWS_H
+
+#include <__chrono/duration.h>
+#include <__config>
+#include <ctime>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using __libcpp_timespec_t = ::timespec;
+
+//
+// Mutex
+//
+typedef void* __libcpp_mutex_t;
+#define _LIBCPP_MUTEX_INITIALIZER 0
+
+#if defined(_M_IX86) || defined(__i386__) || defined(_M_ARM) || defined(__arm__)
+typedef void* __libcpp_recursive_mutex_t[6];
+#elif defined(_M_AMD64) || defined(__x86_64__) || defined(_M_ARM64) || defined(__aarch64__)
+typedef void* __libcpp_recursive_mutex_t[5];
+#else
+# error Unsupported architecture
+#endif
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_recursive_mutex_init(__libcpp_recursive_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_recursive_mutex_lock(__libcpp_recursive_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS bool
+__libcpp_recursive_mutex_trylock(__libcpp_recursive_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_recursive_mutex_unlock(__libcpp_recursive_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_recursive_mutex_destroy(__libcpp_recursive_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_mutex_lock(__libcpp_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS bool __libcpp_mutex_trylock(__libcpp_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int __libcpp_mutex_unlock(__libcpp_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_mutex_destroy(__libcpp_mutex_t* __m);
+
+//
+// Condition variable
+//
+typedef void* __libcpp_condvar_t;
+#define _LIBCPP_CONDVAR_INITIALIZER 0
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_condvar_signal(__libcpp_condvar_t* __cv);
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_condvar_broadcast(__libcpp_condvar_t* __cv);
+
+_LIBCPP_EXPORTED_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_condvar_wait(__libcpp_condvar_t* __cv, __libcpp_mutex_t* __m);
+
+_LIBCPP_EXPORTED_FROM_ABI _LIBCPP_NO_THREAD_SAFETY_ANALYSIS int
+__libcpp_condvar_timedwait(__libcpp_condvar_t* __cv, __libcpp_mutex_t* __m, __libcpp_timespec_t* __ts);
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_condvar_destroy(__libcpp_condvar_t* __cv);
+
+//
+// Execute once
+//
+typedef void* __libcpp_exec_once_flag;
+#define _LIBCPP_EXEC_ONCE_INITIALIZER 0
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_execute_once(__libcpp_exec_once_flag* __flag, void (*__init_routine)());
+
+//
+// Thread id
+//
+typedef long __libcpp_thread_id;
+
+_LIBCPP_EXPORTED_FROM_ABI bool __libcpp_thread_id_equal(__libcpp_thread_id __t1, __libcpp_thread_id __t2);
+
+_LIBCPP_EXPORTED_FROM_ABI bool __libcpp_thread_id_less(__libcpp_thread_id __t1, __libcpp_thread_id __t2);
+
+//
+// Thread
+//
+#define _LIBCPP_NULL_THREAD 0U
+typedef void* __libcpp_thread_t;
+
+_LIBCPP_EXPORTED_FROM_ABI bool __libcpp_thread_isnull(const __libcpp_thread_t* __t);
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_thread_create(__libcpp_thread_t* __t, void* (*__func)(void*), void* __arg);
+
+_LIBCPP_EXPORTED_FROM_ABI __libcpp_thread_id __libcpp_thread_get_current_id();
+
+_LIBCPP_EXPORTED_FROM_ABI __libcpp_thread_id __libcpp_thread_get_id(const __libcpp_thread_t* __t);
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_thread_join(__libcpp_thread_t* __t);
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_thread_detach(__libcpp_thread_t* __t);
+
+_LIBCPP_EXPORTED_FROM_ABI void __libcpp_thread_yield();
+
+_LIBCPP_EXPORTED_FROM_ABI void __libcpp_thread_sleep_for(const chrono::nanoseconds& __ns);
+
+//
+// Thread local storage
+//
+typedef long __libcpp_tls_key;
+
+#define _LIBCPP_TLS_DESTRUCTOR_CC __stdcall
+
+_LIBCPP_EXPORTED_FROM_ABI int
+__libcpp_tls_create(__libcpp_tls_key* __key, void(_LIBCPP_TLS_DESTRUCTOR_CC* __at_exit)(void*));
+
+_LIBCPP_EXPORTED_FROM_ABI void* __libcpp_tls_get(__libcpp_tls_key __key);
+
+_LIBCPP_EXPORTED_FROM_ABI int __libcpp_tls_set(__libcpp_tls_key __key, void* __p);
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___THREAD_SUPPORT_WINDOWS_H
diff --git a/libcxx/include/__cxx03/__thread/this_thread.h b/libcxx/include/__cxx03/__thread/this_thread.h
new file mode 100644
index 00000000000000..de7eea282c8749
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/this_thread.h
@@ -0,0 +1,74 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_THIS_THREAD_H
+#define _LIBCPP___THREAD_THIS_THREAD_H
+
+#include <__chrono/steady_clock.h>
+#include <__chrono/time_point.h>
+#include <__condition_variable/condition_variable.h>
+#include <__config>
+#include <__mutex/mutex.h>
+#include <__mutex/unique_lock.h>
+#include <__thread/support.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace this_thread {
+
+_LIBCPP_EXPORTED_FROM_ABI void sleep_for(const chrono::nanoseconds& __ns);
+
+template <class _Rep, class _Period>
+_LIBCPP_HIDE_FROM_ABI void sleep_for(const chrono::duration<_Rep, _Period>& __d) {
+ if (__d > chrono::duration<_Rep, _Period>::zero()) {
+ // The standard guarantees a 64bit signed integer resolution for nanoseconds,
+ // so use INT64_MAX / 1e9 as cut-off point. Use a constant to avoid <climits>
+ // and issues with long double folding on PowerPC with GCC.
+ _LIBCPP_CONSTEXPR chrono::duration<long double> __max = chrono::duration<long double>(9223372036.0L);
+ chrono::nanoseconds __ns;
+ if (__d < __max) {
+ __ns = chrono::duration_cast<chrono::nanoseconds>(__d);
+ if (__ns < __d)
+ ++__ns;
+ } else
+ __ns = chrono::nanoseconds::max();
+ this_thread::sleep_for(__ns);
+ }
+}
+
+template <class _Clock, class _Duration>
+_LIBCPP_HIDE_FROM_ABI void sleep_until(const chrono::time_point<_Clock, _Duration>& __t) {
+ mutex __mut;
+ condition_variable __cv;
+ unique_lock<mutex> __lk(__mut);
+ while (_Clock::now() < __t)
+ __cv.wait_until(__lk, __t);
+}
+
+template <class _Duration>
+inline _LIBCPP_HIDE_FROM_ABI void sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t) {
+ this_thread::sleep_for(__t - chrono::steady_clock::now());
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void yield() _NOEXCEPT { __libcpp_thread_yield(); }
+
+} // namespace this_thread
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___THREAD_THIS_THREAD_H
diff --git a/libcxx/include/__cxx03/__thread/thread.h b/libcxx/include/__cxx03/__thread/thread.h
new file mode 100644
index 00000000000000..d2254a695f5e8c
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/thread.h
@@ -0,0 +1,258 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_THREAD_H
+#define _LIBCPP___THREAD_THREAD_H
+
+#include <__condition_variable/condition_variable.h>
+#include <__config>
+#include <__exception/terminate.h>
+#include <__functional/hash.h>
+#include <__functional/unary_function.h>
+#include <__memory/unique_ptr.h>
+#include <__mutex/mutex.h>
+#include <__system_error/system_error.h>
+#include <__thread/id.h>
+#include <__thread/support.h>
+#include <__utility/forward.h>
+#include <tuple>
+
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+# include <locale>
+# include <sstream>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+class __thread_specific_ptr;
+class _LIBCPP_EXPORTED_FROM_ABI __thread_struct;
+class _LIBCPP_HIDDEN __thread_struct_imp;
+class __assoc_sub_state;
+
+_LIBCPP_EXPORTED_FROM_ABI __thread_specific_ptr<__thread_struct>& __thread_local_data();
+
+class _LIBCPP_EXPORTED_FROM_ABI __thread_struct {
+ __thread_struct_imp* __p_;
+
+ __thread_struct(const __thread_struct&);
+ __thread_struct& operator=(const __thread_struct&);
+
+public:
+ __thread_struct();
+ ~__thread_struct();
+
+ void notify_all_at_thread_exit(condition_variable*, mutex*);
+ void __make_ready_at_thread_exit(__assoc_sub_state*);
+};
+
+template <class _Tp>
+class __thread_specific_ptr {
+ __libcpp_tls_key __key_;
+
+ // Only __thread_local_data() may construct a __thread_specific_ptr
+ // and only with _Tp == __thread_struct.
+ static_assert(is_same<_Tp, __thread_struct>::value, "");
+ __thread_specific_ptr();
+ friend _LIBCPP_EXPORTED_FROM_ABI __thread_specific_ptr<__thread_struct>& __thread_local_data();
+
+ _LIBCPP_HIDDEN static void _LIBCPP_TLS_DESTRUCTOR_CC __at_thread_exit(void*);
+
+public:
+ typedef _Tp* pointer;
+
+ __thread_specific_ptr(const __thread_specific_ptr&) = delete;
+ __thread_specific_ptr& operator=(const __thread_specific_ptr&) = delete;
+ ~__thread_specific_ptr();
+
+ _LIBCPP_HIDE_FROM_ABI pointer get() const { return static_cast<_Tp*>(__libcpp_tls_get(__key_)); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator*() const { return *get(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return get(); }
+ void set_pointer(pointer __p);
+};
+
+template <class _Tp>
+void _LIBCPP_TLS_DESTRUCTOR_CC __thread_specific_ptr<_Tp>::__at_thread_exit(void* __p) {
+ delete static_cast<pointer>(__p);
+}
+
+template <class _Tp>
+__thread_specific_ptr<_Tp>::__thread_specific_ptr() {
+ int __ec = __libcpp_tls_create(&__key_, &__thread_specific_ptr::__at_thread_exit);
+ if (__ec)
+ __throw_system_error(__ec, "__thread_specific_ptr construction failed");
+}
+
+template <class _Tp>
+__thread_specific_ptr<_Tp>::~__thread_specific_ptr() {
+ // __thread_specific_ptr is only created with a static storage duration
+ // so this destructor is only invoked during program termination. Invoking
+ // pthread_key_delete(__key_) may prevent other threads from deleting their
+ // thread local data. For this reason we leak the key.
+}
+
+template <class _Tp>
+void __thread_specific_ptr<_Tp>::set_pointer(pointer __p) {
+ _LIBCPP_ASSERT_INTERNAL(get() == nullptr, "Attempting to overwrite thread local data");
+ std::__libcpp_tls_set(__key_, __p);
+}
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<__thread_id> : public __unary_function<__thread_id, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(__thread_id __v) const _NOEXCEPT {
+ return hash<__libcpp_thread_id>()(__v.__id_);
+ }
+};
+
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id) {
+ // [thread.thread.id]/9
+ // Effects: Inserts the text representation for charT of id into out.
+ //
+ // [thread.thread.id]/2
+ // The text representation for the character type charT of an
+ // object of type thread::id is an unspecified sequence of charT
+ // such that, for two objects of type thread::id x and y, if
+ // x == y is true, the thread::id objects have the same text
+ // representation, and if x != y is true, the thread::id objects
+ // have distinct text representations.
+ //
+ // Since various flags in the output stream can affect how the
+ // thread id is represented (e.g. numpunct or showbase), we
+ // use a temporary stream instead and just output the thread
+ // id representation as a string.
+
+ basic_ostringstream<_CharT, _Traits> __sstr;
+ __sstr.imbue(locale::classic());
+ __sstr << __id.__id_;
+ return __os << __sstr.str();
+}
+#endif // _LIBCPP_HAS_NO_LOCALIZATION
+
+class _LIBCPP_EXPORTED_FROM_ABI thread {
+ __libcpp_thread_t __t_;
+
+ thread(const thread&);
+ thread& operator=(const thread&);
+
+public:
+ typedef __thread_id id;
+ typedef __libcpp_thread_t native_handle_type;
+
+ _LIBCPP_HIDE_FROM_ABI thread() _NOEXCEPT : __t_(_LIBCPP_NULL_THREAD) {}
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Fp, class... _Args, __enable_if_t<!is_same<__remove_cvref_t<_Fp>, thread>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS explicit thread(_Fp&& __f, _Args&&... __args);
+#else // _LIBCPP_CXX03_LANG
+ template <class _Fp>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS explicit thread(_Fp __f);
+#endif
+ ~thread();
+
+ _LIBCPP_HIDE_FROM_ABI thread(thread&& __t) _NOEXCEPT : __t_(__t.__t_) { __t.__t_ = _LIBCPP_NULL_THREAD; }
+
+ _LIBCPP_HIDE_FROM_ABI thread& operator=(thread&& __t) _NOEXCEPT {
+ if (!__libcpp_thread_isnull(&__t_))
+ terminate();
+ __t_ = __t.__t_;
+ __t.__t_ = _LIBCPP_NULL_THREAD;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(thread& __t) _NOEXCEPT { std::swap(__t_, __t.__t_); }
+
+ _LIBCPP_HIDE_FROM_ABI bool joinable() const _NOEXCEPT { return !__libcpp_thread_isnull(&__t_); }
+ void join();
+ void detach();
+ _LIBCPP_HIDE_FROM_ABI id get_id() const _NOEXCEPT { return __libcpp_thread_get_id(&__t_); }
+ _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() _NOEXCEPT { return __t_; }
+
+ static unsigned hardware_concurrency() _NOEXCEPT;
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _TSp, class _Fp, class... _Args, size_t... _Indices>
+inline _LIBCPP_HIDE_FROM_ABI void __thread_execute(tuple<_TSp, _Fp, _Args...>& __t, __tuple_indices<_Indices...>) {
+ std::__invoke(std::move(std::get<1>(__t)), std::move(std::get<_Indices>(__t))...);
+}
+
+template <class _Fp>
+_LIBCPP_HIDE_FROM_ABI void* __thread_proxy(void* __vp) {
+ // _Fp = tuple< unique_ptr<__thread_struct>, Functor, Args...>
+ unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
+ __thread_local_data().set_pointer(std::get<0>(*__p.get()).release());
+ typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 2>::type _Index;
+ std::__thread_execute(*__p.get(), _Index());
+ return nullptr;
+}
+
+template <class _Fp, class... _Args, __enable_if_t<!is_same<__remove_cvref_t<_Fp>, thread>::value, int> >
+thread::thread(_Fp&& __f, _Args&&... __args) {
+ typedef unique_ptr<__thread_struct> _TSPtr;
+ _TSPtr __tsp(new __thread_struct);
+ typedef tuple<_TSPtr, __decay_t<_Fp>, __decay_t<_Args>...> _Gp;
+ unique_ptr<_Gp> __p(new _Gp(std::move(__tsp), std::forward<_Fp>(__f), std::forward<_Args>(__args)...));
+ int __ec = std::__libcpp_thread_create(&__t_, &__thread_proxy<_Gp>, __p.get());
+ if (__ec == 0)
+ __p.release();
+ else
+ __throw_system_error(__ec, "thread constructor failed");
+}
+
+#else // _LIBCPP_CXX03_LANG
+
+template <class _Fp>
+struct __thread_invoke_pair {
+ // This type is used to pass memory for thread local storage and a functor
+ // to a newly created thread because std::pair doesn't work with
+ // std::unique_ptr in C++03.
+ _LIBCPP_HIDE_FROM_ABI __thread_invoke_pair(_Fp& __f) : __tsp_(new __thread_struct), __fn_(__f) {}
+ unique_ptr<__thread_struct> __tsp_;
+ _Fp __fn_;
+};
+
+template <class _Fp>
+_LIBCPP_HIDE_FROM_ABI void* __thread_proxy_cxx03(void* __vp) {
+ unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
+ __thread_local_data().set_pointer(__p->__tsp_.release());
+ (__p->__fn_)();
+ return nullptr;
+}
+
+template <class _Fp>
+thread::thread(_Fp __f) {
+ typedef __thread_invoke_pair<_Fp> _InvokePair;
+ typedef unique_ptr<_InvokePair> _PairPtr;
+ _PairPtr __pp(new _InvokePair(__f));
+ int __ec = std::__libcpp_thread_create(&__t_, &__thread_proxy_cxx03<_InvokePair>, __pp.get());
+ if (__ec == 0)
+ __pp.release();
+ else
+ __throw_system_error(__ec, "thread constructor failed");
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+inline _LIBCPP_HIDE_FROM_ABI void swap(thread& __x, thread& __y) _NOEXCEPT { __x.swap(__y); }
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___THREAD_THREAD_H
diff --git a/libcxx/include/__cxx03/__thread/timed_backoff_policy.h b/libcxx/include/__cxx03/__thread/timed_backoff_policy.h
new file mode 100644
index 00000000000000..838c918a57ef0d
--- /dev/null
+++ b/libcxx/include/__cxx03/__thread/timed_backoff_policy.h
@@ -0,0 +1,44 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___THREAD_TIMED_BACKOFF_POLICY_H
+#define _LIBCPP___THREAD_TIMED_BACKOFF_POLICY_H
+
+#include <__config>
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+
+# include <__chrono/duration.h>
+# include <__thread/support.h>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __libcpp_timed_backoff_policy {
+ _LIBCPP_HIDE_FROM_ABI bool operator()(chrono::nanoseconds __elapsed) const {
+ if (__elapsed > chrono::milliseconds(128))
+ __libcpp_thread_sleep_for(chrono::milliseconds(8));
+ else if (__elapsed > chrono::microseconds(64))
+ __libcpp_thread_sleep_for(__elapsed / 2);
+ else if (__elapsed > chrono::microseconds(4))
+ __libcpp_thread_yield();
+ else {
+ } // poll
+ return false;
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_HAS_NO_THREADS
+
+#endif // _LIBCPP___THREAD_TIMED_BACKOFF_POLICY_H
diff --git a/libcxx/include/__cxx03/__tree b/libcxx/include/__cxx03/__tree
new file mode 100644
index 00000000000000..1990fa602d39ca
--- /dev/null
+++ b/libcxx/include/__cxx03/__tree
@@ -0,0 +1,2299 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TREE
+#define _LIBCPP___TREE
+
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__config>
+#include <__functional/invoke.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/compressed_pair.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/swap_allocator.h>
+#include <__memory/unique_ptr.h>
+#include <__type_traits/can_extract_key.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/remove_const_ref.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/swap.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class, class, class, class>
+class _LIBCPP_TEMPLATE_VIS map;
+template <class, class, class, class>
+class _LIBCPP_TEMPLATE_VIS multimap;
+template <class, class, class>
+class _LIBCPP_TEMPLATE_VIS set;
+template <class, class, class>
+class _LIBCPP_TEMPLATE_VIS multiset;
+
+template <class _Tp, class _Compare, class _Allocator>
+class __tree;
+template <class _Tp, class _NodePtr, class _DiffType>
+class _LIBCPP_TEMPLATE_VIS __tree_iterator;
+template <class _Tp, class _ConstNodePtr, class _DiffType>
+class _LIBCPP_TEMPLATE_VIS __tree_const_iterator;
+
+template <class _Pointer>
+class __tree_end_node;
+template <class _VoidPtr>
+class __tree_node_base;
+template <class _Tp, class _VoidPtr>
+class __tree_node;
+
+template <class _Key, class _Value>
+struct __value_type;
+
+template <class _Allocator>
+class __map_node_destructor;
+template <class _TreeIterator>
+class _LIBCPP_TEMPLATE_VIS __map_iterator;
+template <class _TreeIterator>
+class _LIBCPP_TEMPLATE_VIS __map_const_iterator;
+
+/*
+
+_NodePtr algorithms
+
+The algorithms taking _NodePtr are red black tree algorithms. Those
+algorithms taking a parameter named __root should assume that __root
+points to a proper red black tree (unless otherwise specified).
+
+Each algorithm herein assumes that __root->__parent_ points to a non-null
+structure which has a member __left_ which points back to __root. No other
+member is read or written to at __root->__parent_.
+
+__root->__parent_ will be referred to below (in comments only) as end_node.
+end_node->__left_ is an externably accessible lvalue for __root, and can be
+changed by node insertion and removal (without explicit reference to end_node).
+
+All nodes (with the exception of end_node), even the node referred to as
+__root, have a non-null __parent_ field.
+
+*/
+
+// Returns: true if __x is a left child of its parent, else false
+// Precondition: __x != nullptr.
+template <class _NodePtr>
+inline _LIBCPP_HIDE_FROM_ABI bool __tree_is_left_child(_NodePtr __x) _NOEXCEPT {
+ return __x == __x->__parent_->__left_;
+}
+
+// Determines if the subtree rooted at __x is a proper red black subtree. If
+// __x is a proper subtree, returns the black height (null counts as 1). If
+// __x is an improper subtree, returns 0.
+template <class _NodePtr>
+unsigned __tree_sub_invariant(_NodePtr __x) {
+ if (__x == nullptr)
+ return 1;
+ // parent consistency checked by caller
+ // check __x->__left_ consistency
+ if (__x->__left_ != nullptr && __x->__left_->__parent_ != __x)
+ return 0;
+ // check __x->__right_ consistency
+ if (__x->__right_ != nullptr && __x->__right_->__parent_ != __x)
+ return 0;
+ // check __x->__left_ != __x->__right_ unless both are nullptr
+ if (__x->__left_ == __x->__right_ && __x->__left_ != nullptr)
+ return 0;
+ // If this is red, neither child can be red
+ if (!__x->__is_black_) {
+ if (__x->__left_ && !__x->__left_->__is_black_)
+ return 0;
+ if (__x->__right_ && !__x->__right_->__is_black_)
+ return 0;
+ }
+ unsigned __h = std::__tree_sub_invariant(__x->__left_);
+ if (__h == 0)
+ return 0; // invalid left subtree
+ if (__h != std::__tree_sub_invariant(__x->__right_))
+ return 0; // invalid or different height right subtree
+ return __h + __x->__is_black_; // return black height of this node
+}
+
+// Determines if the red black tree rooted at __root is a proper red black tree.
+// __root == nullptr is a proper tree. Returns true is __root is a proper
+// red black tree, else returns false.
+template <class _NodePtr>
+_LIBCPP_HIDE_FROM_ABI bool __tree_invariant(_NodePtr __root) {
+ if (__root == nullptr)
+ return true;
+ // check __x->__parent_ consistency
+ if (__root->__parent_ == nullptr)
+ return false;
+ if (!std::__tree_is_left_child(__root))
+ return false;
+ // root must be black
+ if (!__root->__is_black_)
+ return false;
+ // do normal node checks
+ return std::__tree_sub_invariant(__root) != 0;
+}
+
+// Returns: pointer to the left-most node under __x.
+template <class _NodePtr>
+inline _LIBCPP_HIDE_FROM_ABI _NodePtr __tree_min(_NodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "Root node shouldn't be null");
+ while (__x->__left_ != nullptr)
+ __x = __x->__left_;
+ return __x;
+}
+
+// Returns: pointer to the right-most node under __x.
+template <class _NodePtr>
+inline _LIBCPP_HIDE_FROM_ABI _NodePtr __tree_max(_NodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "Root node shouldn't be null");
+ while (__x->__right_ != nullptr)
+ __x = __x->__right_;
+ return __x;
+}
+
+// Returns: pointer to the next in-order node after __x.
+template <class _NodePtr>
+_LIBCPP_HIDE_FROM_ABI _NodePtr __tree_next(_NodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "node shouldn't be null");
+ if (__x->__right_ != nullptr)
+ return std::__tree_min(__x->__right_);
+ while (!std::__tree_is_left_child(__x))
+ __x = __x->__parent_unsafe();
+ return __x->__parent_unsafe();
+}
+
+template <class _EndNodePtr, class _NodePtr>
+inline _LIBCPP_HIDE_FROM_ABI _EndNodePtr __tree_next_iter(_NodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "node shouldn't be null");
+ if (__x->__right_ != nullptr)
+ return static_cast<_EndNodePtr>(std::__tree_min(__x->__right_));
+ while (!std::__tree_is_left_child(__x))
+ __x = __x->__parent_unsafe();
+ return static_cast<_EndNodePtr>(__x->__parent_);
+}
+
+// Returns: pointer to the previous in-order node before __x.
+// Note: __x may be the end node.
+template <class _NodePtr, class _EndNodePtr>
+inline _LIBCPP_HIDE_FROM_ABI _NodePtr __tree_prev_iter(_EndNodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "node shouldn't be null");
+ if (__x->__left_ != nullptr)
+ return std::__tree_max(__x->__left_);
+ _NodePtr __xx = static_cast<_NodePtr>(__x);
+ while (std::__tree_is_left_child(__xx))
+ __xx = __xx->__parent_unsafe();
+ return __xx->__parent_unsafe();
+}
+
+// Returns: pointer to a node which has no children
+template <class _NodePtr>
+_LIBCPP_HIDE_FROM_ABI _NodePtr __tree_leaf(_NodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "node shouldn't be null");
+ while (true) {
+ if (__x->__left_ != nullptr) {
+ __x = __x->__left_;
+ continue;
+ }
+ if (__x->__right_ != nullptr) {
+ __x = __x->__right_;
+ continue;
+ }
+ break;
+ }
+ return __x;
+}
+
+// Effects: Makes __x->__right_ the subtree root with __x as its left child
+// while preserving in-order order.
+template <class _NodePtr>
+_LIBCPP_HIDE_FROM_ABI void __tree_left_rotate(_NodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "node shouldn't be null");
+ _LIBCPP_ASSERT_INTERNAL(__x->__right_ != nullptr, "node should have a right child");
+ _NodePtr __y = __x->__right_;
+ __x->__right_ = __y->__left_;
+ if (__x->__right_ != nullptr)
+ __x->__right_->__set_parent(__x);
+ __y->__parent_ = __x->__parent_;
+ if (std::__tree_is_left_child(__x))
+ __x->__parent_->__left_ = __y;
+ else
+ __x->__parent_unsafe()->__right_ = __y;
+ __y->__left_ = __x;
+ __x->__set_parent(__y);
+}
+
+// Effects: Makes __x->__left_ the subtree root with __x as its right child
+// while preserving in-order order.
+template <class _NodePtr>
+_LIBCPP_HIDE_FROM_ABI void __tree_right_rotate(_NodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "node shouldn't be null");
+ _LIBCPP_ASSERT_INTERNAL(__x->__left_ != nullptr, "node should have a left child");
+ _NodePtr __y = __x->__left_;
+ __x->__left_ = __y->__right_;
+ if (__x->__left_ != nullptr)
+ __x->__left_->__set_parent(__x);
+ __y->__parent_ = __x->__parent_;
+ if (std::__tree_is_left_child(__x))
+ __x->__parent_->__left_ = __y;
+ else
+ __x->__parent_unsafe()->__right_ = __y;
+ __y->__right_ = __x;
+ __x->__set_parent(__y);
+}
+
+// Effects: Rebalances __root after attaching __x to a leaf.
+// Precondition: __x has no children.
+// __x == __root or == a direct or indirect child of __root.
+// If __x were to be unlinked from __root (setting __root to
+// nullptr if __root == __x), __tree_invariant(__root) == true.
+// Postcondition: __tree_invariant(end_node->__left_) == true. end_node->__left_
+// may be different than the value passed in as __root.
+template <class _NodePtr>
+_LIBCPP_HIDE_FROM_ABI void __tree_balance_after_insert(_NodePtr __root, _NodePtr __x) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__root != nullptr, "Root of the tree shouldn't be null");
+ _LIBCPP_ASSERT_INTERNAL(__x != nullptr, "Can't attach null node to a leaf");
+ __x->__is_black_ = __x == __root;
+ while (__x != __root && !__x->__parent_unsafe()->__is_black_) {
+ // __x->__parent_ != __root because __x->__parent_->__is_black == false
+ if (std::__tree_is_left_child(__x->__parent_unsafe())) {
+ _NodePtr __y = __x->__parent_unsafe()->__parent_unsafe()->__right_;
+ if (__y != nullptr && !__y->__is_black_) {
+ __x = __x->__parent_unsafe();
+ __x->__is_black_ = true;
+ __x = __x->__parent_unsafe();
+ __x->__is_black_ = __x == __root;
+ __y->__is_black_ = true;
+ } else {
+ if (!std::__tree_is_left_child(__x)) {
+ __x = __x->__parent_unsafe();
+ std::__tree_left_rotate(__x);
+ }
+ __x = __x->__parent_unsafe();
+ __x->__is_black_ = true;
+ __x = __x->__parent_unsafe();
+ __x->__is_black_ = false;
+ std::__tree_right_rotate(__x);
+ break;
+ }
+ } else {
+ _NodePtr __y = __x->__parent_unsafe()->__parent_->__left_;
+ if (__y != nullptr && !__y->__is_black_) {
+ __x = __x->__parent_unsafe();
+ __x->__is_black_ = true;
+ __x = __x->__parent_unsafe();
+ __x->__is_black_ = __x == __root;
+ __y->__is_black_ = true;
+ } else {
+ if (std::__tree_is_left_child(__x)) {
+ __x = __x->__parent_unsafe();
+ std::__tree_right_rotate(__x);
+ }
+ __x = __x->__parent_unsafe();
+ __x->__is_black_ = true;
+ __x = __x->__parent_unsafe();
+ __x->__is_black_ = false;
+ std::__tree_left_rotate(__x);
+ break;
+ }
+ }
+ }
+}
+
+// Precondition: __z == __root or == a direct or indirect child of __root.
+// Effects: unlinks __z from the tree rooted at __root, rebalancing as needed.
+// Postcondition: __tree_invariant(end_node->__left_) == true && end_node->__left_
+// nor any of its children refer to __z. end_node->__left_
+// may be different than the value passed in as __root.
+template <class _NodePtr>
+_LIBCPP_HIDE_FROM_ABI void __tree_remove(_NodePtr __root, _NodePtr __z) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__root != nullptr, "Root node should not be null");
+ _LIBCPP_ASSERT_INTERNAL(__z != nullptr, "The node to remove should not be null");
+ _LIBCPP_ASSERT_INTERNAL(std::__tree_invariant(__root), "The tree invariants should hold");
+ // __z will be removed from the tree. Client still needs to destruct/deallocate it
+ // __y is either __z, or if __z has two children, __tree_next(__z).
+ // __y will have at most one child.
+ // __y will be the initial hole in the tree (make the hole at a leaf)
+ _NodePtr __y = (__z->__left_ == nullptr || __z->__right_ == nullptr) ? __z : std::__tree_next(__z);
+ // __x is __y's possibly null single child
+ _NodePtr __x = __y->__left_ != nullptr ? __y->__left_ : __y->__right_;
+ // __w is __x's possibly null uncle (will become __x's sibling)
+ _NodePtr __w = nullptr;
+ // link __x to __y's parent, and find __w
+ if (__x != nullptr)
+ __x->__parent_ = __y->__parent_;
+ if (std::__tree_is_left_child(__y)) {
+ __y->__parent_->__left_ = __x;
+ if (__y != __root)
+ __w = __y->__parent_unsafe()->__right_;
+ else
+ __root = __x; // __w == nullptr
+ } else {
+ __y->__parent_unsafe()->__right_ = __x;
+ // __y can't be root if it is a right child
+ __w = __y->__parent_->__left_;
+ }
+ bool __removed_black = __y->__is_black_;
+ // If we didn't remove __z, do so now by splicing in __y for __z,
+ // but copy __z's color. This does not impact __x or __w.
+ if (__y != __z) {
+ // __z->__left_ != nulptr but __z->__right_ might == __x == nullptr
+ __y->__parent_ = __z->__parent_;
+ if (std::__tree_is_left_child(__z))
+ __y->__parent_->__left_ = __y;
+ else
+ __y->__parent_unsafe()->__right_ = __y;
+ __y->__left_ = __z->__left_;
+ __y->__left_->__set_parent(__y);
+ __y->__right_ = __z->__right_;
+ if (__y->__right_ != nullptr)
+ __y->__right_->__set_parent(__y);
+ __y->__is_black_ = __z->__is_black_;
+ if (__root == __z)
+ __root = __y;
+ }
+ // There is no need to rebalance if we removed a red, or if we removed
+ // the last node.
+ if (__removed_black && __root != nullptr) {
+ // Rebalance:
+ // __x has an implicit black color (transferred from the removed __y)
+ // associated with it, no matter what its color is.
+ // If __x is __root (in which case it can't be null), it is supposed
+ // to be black anyway, and if it is doubly black, then the double
+ // can just be ignored.
+ // If __x is red (in which case it can't be null), then it can absorb
+ // the implicit black just by setting its color to black.
+ // Since __y was black and only had one child (which __x points to), __x
+ // is either red with no children, else null, otherwise __y would have
+ // different black heights under left and right pointers.
+ // if (__x == __root || __x != nullptr && !__x->__is_black_)
+ if (__x != nullptr)
+ __x->__is_black_ = true;
+ else {
+ // Else __x isn't root, and is "doubly black", even though it may
+ // be null. __w can not be null here, else the parent would
+ // see a black height >= 2 on the __x side and a black height
+ // of 1 on the __w side (__w must be a non-null black or a red
+ // with a non-null black child).
+ while (true) {
+ if (!std::__tree_is_left_child(__w)) // if x is left child
+ {
+ if (!__w->__is_black_) {
+ __w->__is_black_ = true;
+ __w->__parent_unsafe()->__is_black_ = false;
+ std::__tree_left_rotate(__w->__parent_unsafe());
+ // __x is still valid
+ // reset __root only if necessary
+ if (__root == __w->__left_)
+ __root = __w;
+ // reset sibling, and it still can't be null
+ __w = __w->__left_->__right_;
+ }
+ // __w->__is_black_ is now true, __w may have null children
+ if ((__w->__left_ == nullptr || __w->__left_->__is_black_) &&
+ (__w->__right_ == nullptr || __w->__right_->__is_black_)) {
+ __w->__is_black_ = false;
+ __x = __w->__parent_unsafe();
+ // __x can no longer be null
+ if (__x == __root || !__x->__is_black_) {
+ __x->__is_black_ = true;
+ break;
+ }
+ // reset sibling, and it still can't be null
+ __w = std::__tree_is_left_child(__x) ? __x->__parent_unsafe()->__right_ : __x->__parent_->__left_;
+ // continue;
+ } else // __w has a red child
+ {
+ if (__w->__right_ == nullptr || __w->__right_->__is_black_) {
+ // __w left child is non-null and red
+ __w->__left_->__is_black_ = true;
+ __w->__is_black_ = false;
+ std::__tree_right_rotate(__w);
+ // __w is known not to be root, so root hasn't changed
+ // reset sibling, and it still can't be null
+ __w = __w->__parent_unsafe();
+ }
+ // __w has a right red child, left child may be null
+ __w->__is_black_ = __w->__parent_unsafe()->__is_black_;
+ __w->__parent_unsafe()->__is_black_ = true;
+ __w->__right_->__is_black_ = true;
+ std::__tree_left_rotate(__w->__parent_unsafe());
+ break;
+ }
+ } else {
+ if (!__w->__is_black_) {
+ __w->__is_black_ = true;
+ __w->__parent_unsafe()->__is_black_ = false;
+ std::__tree_right_rotate(__w->__parent_unsafe());
+ // __x is still valid
+ // reset __root only if necessary
+ if (__root == __w->__right_)
+ __root = __w;
+ // reset sibling, and it still can't be null
+ __w = __w->__right_->__left_;
+ }
+ // __w->__is_black_ is now true, __w may have null children
+ if ((__w->__left_ == nullptr || __w->__left_->__is_black_) &&
+ (__w->__right_ == nullptr || __w->__right_->__is_black_)) {
+ __w->__is_black_ = false;
+ __x = __w->__parent_unsafe();
+ // __x can no longer be null
+ if (!__x->__is_black_ || __x == __root) {
+ __x->__is_black_ = true;
+ break;
+ }
+ // reset sibling, and it still can't be null
+ __w = std::__tree_is_left_child(__x) ? __x->__parent_unsafe()->__right_ : __x->__parent_->__left_;
+ // continue;
+ } else // __w has a red child
+ {
+ if (__w->__left_ == nullptr || __w->__left_->__is_black_) {
+ // __w right child is non-null and red
+ __w->__right_->__is_black_ = true;
+ __w->__is_black_ = false;
+ std::__tree_left_rotate(__w);
+ // __w is known not to be root, so root hasn't changed
+ // reset sibling, and it still can't be null
+ __w = __w->__parent_unsafe();
+ }
+ // __w has a left red child, right child may be null
+ __w->__is_black_ = __w->__parent_unsafe()->__is_black_;
+ __w->__parent_unsafe()->__is_black_ = true;
+ __w->__left_->__is_black_ = true;
+ std::__tree_right_rotate(__w->__parent_unsafe());
+ break;
+ }
+ }
+ }
+ }
+ }
+}
+
+// node traits
+
+template <class _Tp>
+struct __is_tree_value_type_imp : false_type {};
+
+template <class _Key, class _Value>
+struct __is_tree_value_type_imp<__value_type<_Key, _Value> > : true_type {};
+
+template <class... _Args>
+struct __is_tree_value_type : false_type {};
+
+template <class _One>
+struct __is_tree_value_type<_One> : __is_tree_value_type_imp<__remove_cvref_t<_One> > {};
+
+template <class _Tp>
+struct __tree_key_value_types {
+ typedef _Tp key_type;
+ typedef _Tp __node_value_type;
+ typedef _Tp __container_value_type;
+ static const bool __is_map = false;
+
+ _LIBCPP_HIDE_FROM_ABI static key_type const& __get_key(_Tp const& __v) { return __v; }
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type const& __get_value(__node_value_type const& __v) { return __v; }
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type* __get_ptr(__node_value_type& __n) { return std::addressof(__n); }
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type&& __move(__node_value_type& __v) { return std::move(__v); }
+};
+
+template <class _Key, class _Tp>
+struct __tree_key_value_types<__value_type<_Key, _Tp> > {
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef __value_type<_Key, _Tp> __node_value_type;
+ typedef pair<const _Key, _Tp> __container_value_type;
+ typedef __container_value_type __map_value_type;
+ static const bool __is_map = true;
+
+ _LIBCPP_HIDE_FROM_ABI static key_type const& __get_key(__node_value_type const& __t) {
+ return __t.__get_value().first;
+ }
+
+ template <class _Up, __enable_if_t<__is_same_uncvref<_Up, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static key_type const& __get_key(_Up& __t) {
+ return __t.first;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type const& __get_value(__node_value_type const& __t) {
+ return __t.__get_value();
+ }
+
+ template <class _Up, __enable_if_t<__is_same_uncvref<_Up, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type const& __get_value(_Up& __t) {
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static __container_value_type* __get_ptr(__node_value_type& __n) {
+ return std::addressof(__n.__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static pair<key_type&&, mapped_type&&> __move(__node_value_type& __v) { return __v.__move(); }
+};
+
+template <class _VoidPtr>
+struct __tree_node_base_types {
+ typedef _VoidPtr __void_pointer;
+
+ typedef __tree_node_base<__void_pointer> __node_base_type;
+ typedef __rebind_pointer_t<_VoidPtr, __node_base_type> __node_base_pointer;
+
+ typedef __tree_end_node<__node_base_pointer> __end_node_type;
+ typedef __rebind_pointer_t<_VoidPtr, __end_node_type> __end_node_pointer;
+#if defined(_LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB)
+ typedef __end_node_pointer __parent_pointer;
+#else
+ typedef __conditional_t< is_pointer<__end_node_pointer>::value, __end_node_pointer, __node_base_pointer>
+ __parent_pointer;
+#endif
+
+private:
+ static_assert(is_same<typename pointer_traits<_VoidPtr>::element_type, void>::value,
+ "_VoidPtr does not point to unqualified void type");
+};
+
+template <class _Tp, class _AllocPtr, class _KVTypes = __tree_key_value_types<_Tp>, bool = _KVTypes::__is_map>
+struct __tree_map_pointer_types {};
+
+template <class _Tp, class _AllocPtr, class _KVTypes>
+struct __tree_map_pointer_types<_Tp, _AllocPtr, _KVTypes, true> {
+ typedef typename _KVTypes::__map_value_type _Mv;
+ typedef __rebind_pointer_t<_AllocPtr, _Mv> __map_value_type_pointer;
+ typedef __rebind_pointer_t<_AllocPtr, const _Mv> __const_map_value_type_pointer;
+};
+
+template <class _NodePtr, class _NodeT = typename pointer_traits<_NodePtr>::element_type>
+struct __tree_node_types;
+
+template <class _NodePtr, class _Tp, class _VoidPtr>
+struct __tree_node_types<_NodePtr, __tree_node<_Tp, _VoidPtr> >
+ : public __tree_node_base_types<_VoidPtr>, __tree_key_value_types<_Tp>, __tree_map_pointer_types<_Tp, _VoidPtr> {
+ typedef __tree_node_base_types<_VoidPtr> __base;
+ typedef __tree_key_value_types<_Tp> __key_base;
+ typedef __tree_map_pointer_types<_Tp, _VoidPtr> __map_pointer_base;
+
+public:
+ typedef typename pointer_traits<_NodePtr>::element_type __node_type;
+ typedef _NodePtr __node_pointer;
+
+ typedef _Tp __node_value_type;
+ typedef __rebind_pointer_t<_VoidPtr, __node_value_type> __node_value_type_pointer;
+ typedef __rebind_pointer_t<_VoidPtr, const __node_value_type> __const_node_value_type_pointer;
+#if defined(_LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB)
+ typedef typename __base::__end_node_pointer __iter_pointer;
+#else
+ typedef __conditional_t< is_pointer<__node_pointer>::value, typename __base::__end_node_pointer, __node_pointer>
+ __iter_pointer;
+#endif
+
+private:
+ static_assert(!is_const<__node_type>::value, "_NodePtr should never be a pointer to const");
+ static_assert(is_same<__rebind_pointer_t<_VoidPtr, __node_type>, _NodePtr>::value,
+ "_VoidPtr does not rebind to _NodePtr.");
+};
+
+template <class _ValueTp, class _VoidPtr>
+struct __make_tree_node_types {
+ typedef __rebind_pointer_t<_VoidPtr, __tree_node<_ValueTp, _VoidPtr> > _NodePtr;
+ typedef __tree_node_types<_NodePtr> type;
+};
+
+// node
+
+template <class _Pointer>
+class __tree_end_node {
+public:
+ typedef _Pointer pointer;
+ pointer __left_;
+
+ _LIBCPP_HIDE_FROM_ABI __tree_end_node() _NOEXCEPT : __left_() {}
+};
+
+template <class _VoidPtr>
+class _LIBCPP_STANDALONE_DEBUG __tree_node_base : public __tree_node_base_types<_VoidPtr>::__end_node_type {
+ typedef __tree_node_base_types<_VoidPtr> _NodeBaseTypes;
+
+public:
+ typedef typename _NodeBaseTypes::__node_base_pointer pointer;
+ typedef typename _NodeBaseTypes::__parent_pointer __parent_pointer;
+
+ pointer __right_;
+ __parent_pointer __parent_;
+ bool __is_black_;
+
+ _LIBCPP_HIDE_FROM_ABI pointer __parent_unsafe() const { return static_cast<pointer>(__parent_); }
+
+ _LIBCPP_HIDE_FROM_ABI void __set_parent(pointer __p) { __parent_ = static_cast<__parent_pointer>(__p); }
+
+ ~__tree_node_base() = delete;
+ __tree_node_base(__tree_node_base const&) = delete;
+ __tree_node_base& operator=(__tree_node_base const&) = delete;
+};
+
+template <class _Tp, class _VoidPtr>
+class _LIBCPP_STANDALONE_DEBUG __tree_node : public __tree_node_base<_VoidPtr> {
+public:
+ typedef _Tp __node_value_type;
+
+ __node_value_type __value_;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp& __get_value() { return __value_; }
+
+ ~__tree_node() = delete;
+ __tree_node(__tree_node const&) = delete;
+ __tree_node& operator=(__tree_node const&) = delete;
+};
+
+template <class _Allocator>
+class __tree_node_destructor {
+ typedef _Allocator allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+
+private:
+ typedef __tree_node_types<pointer> _NodeTypes;
+ allocator_type& __na_;
+
+public:
+ bool __value_constructed;
+
+ _LIBCPP_HIDE_FROM_ABI __tree_node_destructor(const __tree_node_destructor&) = default;
+ __tree_node_destructor& operator=(const __tree_node_destructor&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __tree_node_destructor(allocator_type& __na, bool __val = false) _NOEXCEPT
+ : __na_(__na),
+ __value_constructed(__val) {}
+
+ _LIBCPP_HIDE_FROM_ABI void operator()(pointer __p) _NOEXCEPT {
+ if (__value_constructed)
+ __alloc_traits::destroy(__na_, _NodeTypes::__get_ptr(__p->__value_));
+ if (__p)
+ __alloc_traits::deallocate(__na_, __p, 1);
+ }
+
+ template <class>
+ friend class __map_node_destructor;
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _NodeType, class _Alloc>
+struct __generic_container_node_destructor;
+template <class _Tp, class _VoidPtr, class _Alloc>
+struct __generic_container_node_destructor<__tree_node<_Tp, _VoidPtr>, _Alloc> : __tree_node_destructor<_Alloc> {
+ using __tree_node_destructor<_Alloc>::__tree_node_destructor;
+};
+#endif
+
+template <class _Tp, class _NodePtr, class _DiffType>
+class _LIBCPP_TEMPLATE_VIS __tree_iterator {
+ typedef __tree_node_types<_NodePtr> _NodeTypes;
+ typedef _NodePtr __node_pointer;
+ typedef typename _NodeTypes::__node_base_pointer __node_base_pointer;
+ typedef typename _NodeTypes::__end_node_pointer __end_node_pointer;
+ typedef typename _NodeTypes::__iter_pointer __iter_pointer;
+ typedef pointer_traits<__node_pointer> __pointer_traits;
+
+ __iter_pointer __ptr_;
+
+public:
+ typedef bidirectional_iterator_tag iterator_category;
+ typedef _Tp value_type;
+ typedef _DiffType difference_type;
+ typedef value_type& reference;
+ typedef typename _NodeTypes::__node_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __tree_iterator() _NOEXCEPT
+#if _LIBCPP_STD_VER >= 14
+ : __ptr_(nullptr)
+#endif
+ {
+ }
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __get_np()->__value_; }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return pointer_traits<pointer>::pointer_to(__get_np()->__value_); }
+
+ _LIBCPP_HIDE_FROM_ABI __tree_iterator& operator++() {
+ __ptr_ = static_cast<__iter_pointer>(
+ std::__tree_next_iter<__end_node_pointer>(static_cast<__node_base_pointer>(__ptr_)));
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __tree_iterator operator++(int) {
+ __tree_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __tree_iterator& operator--() {
+ __ptr_ = static_cast<__iter_pointer>(
+ std::__tree_prev_iter<__node_base_pointer>(static_cast<__end_node_pointer>(__ptr_)));
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __tree_iterator operator--(int) {
+ __tree_iterator __t(*this);
+ --(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __tree_iterator& __x, const __tree_iterator& __y) {
+ return __x.__ptr_ == __y.__ptr_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __tree_iterator& __x, const __tree_iterator& __y) {
+ return !(__x == __y);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit __tree_iterator(__node_pointer __p) _NOEXCEPT : __ptr_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI explicit __tree_iterator(__end_node_pointer __p) _NOEXCEPT : __ptr_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __get_np() const { return static_cast<__node_pointer>(__ptr_); }
+ template <class, class, class>
+ friend class __tree;
+ template <class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS __tree_const_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __map_iterator;
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS map;
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS multimap;
+ template <class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS set;
+ template <class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS multiset;
+};
+
+template <class _Tp, class _NodePtr, class _DiffType>
+class _LIBCPP_TEMPLATE_VIS __tree_const_iterator {
+ typedef __tree_node_types<_NodePtr> _NodeTypes;
+ typedef typename _NodeTypes::__node_pointer __node_pointer;
+ typedef typename _NodeTypes::__node_base_pointer __node_base_pointer;
+ typedef typename _NodeTypes::__end_node_pointer __end_node_pointer;
+ typedef typename _NodeTypes::__iter_pointer __iter_pointer;
+ typedef pointer_traits<__node_pointer> __pointer_traits;
+
+ __iter_pointer __ptr_;
+
+public:
+ typedef bidirectional_iterator_tag iterator_category;
+ typedef _Tp value_type;
+ typedef _DiffType difference_type;
+ typedef const value_type& reference;
+ typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __tree_const_iterator() _NOEXCEPT
+#if _LIBCPP_STD_VER >= 14
+ : __ptr_(nullptr)
+#endif
+ {
+ }
+
+private:
+ typedef __tree_iterator<value_type, __node_pointer, difference_type> __non_const_iterator;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __tree_const_iterator(__non_const_iterator __p) _NOEXCEPT : __ptr_(__p.__ptr_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __get_np()->__value_; }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return pointer_traits<pointer>::pointer_to(__get_np()->__value_); }
+
+ _LIBCPP_HIDE_FROM_ABI __tree_const_iterator& operator++() {
+ __ptr_ = static_cast<__iter_pointer>(
+ std::__tree_next_iter<__end_node_pointer>(static_cast<__node_base_pointer>(__ptr_)));
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __tree_const_iterator operator++(int) {
+ __tree_const_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __tree_const_iterator& operator--() {
+ __ptr_ = static_cast<__iter_pointer>(
+ std::__tree_prev_iter<__node_base_pointer>(static_cast<__end_node_pointer>(__ptr_)));
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __tree_const_iterator operator--(int) {
+ __tree_const_iterator __t(*this);
+ --(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __tree_const_iterator& __x, const __tree_const_iterator& __y) {
+ return __x.__ptr_ == __y.__ptr_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __tree_const_iterator& __x, const __tree_const_iterator& __y) {
+ return !(__x == __y);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit __tree_const_iterator(__node_pointer __p) _NOEXCEPT : __ptr_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI explicit __tree_const_iterator(__end_node_pointer __p) _NOEXCEPT : __ptr_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __get_np() const { return static_cast<__node_pointer>(__ptr_); }
+
+ template <class, class, class>
+ friend class __tree;
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS map;
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS multimap;
+ template <class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS set;
+ template <class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS multiset;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __map_const_iterator;
+};
+
+template <class _Tp, class _Compare>
+#ifndef _LIBCPP_CXX03_LANG
+_LIBCPP_DIAGNOSE_WARNING(!__invokable<_Compare const&, _Tp const&, _Tp const&>::value,
+ "the specified comparator type does not provide a viable const call operator")
+#endif
+int __diagnose_non_const_comparator();
+
+template <class _Tp, class _Compare, class _Allocator>
+class __tree {
+public:
+ typedef _Tp value_type;
+ typedef _Compare value_compare;
+ typedef _Allocator allocator_type;
+
+private:
+ typedef allocator_traits<allocator_type> __alloc_traits;
+ typedef typename __make_tree_node_types<value_type, typename __alloc_traits::void_pointer>::type _NodeTypes;
+ typedef typename _NodeTypes::key_type key_type;
+
+public:
+ typedef typename _NodeTypes::__node_value_type __node_value_type;
+ typedef typename _NodeTypes::__container_value_type __container_value_type;
+
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+ typedef typename __alloc_traits::size_type size_type;
+ typedef typename __alloc_traits::difference_type difference_type;
+
+public:
+ typedef typename _NodeTypes::__void_pointer __void_pointer;
+
+ typedef typename _NodeTypes::__node_type __node;
+ typedef typename _NodeTypes::__node_pointer __node_pointer;
+
+ typedef typename _NodeTypes::__node_base_type __node_base;
+ typedef typename _NodeTypes::__node_base_pointer __node_base_pointer;
+
+ typedef typename _NodeTypes::__end_node_type __end_node_t;
+ typedef typename _NodeTypes::__end_node_pointer __end_node_ptr;
+
+ typedef typename _NodeTypes::__parent_pointer __parent_pointer;
+ typedef typename _NodeTypes::__iter_pointer __iter_pointer;
+
+ typedef __rebind_alloc<__alloc_traits, __node> __node_allocator;
+ typedef allocator_traits<__node_allocator> __node_traits;
+
+private:
+ // check for sane allocator pointer rebinding semantics. Rebinding the
+ // allocator for a new pointer type should be exactly the same as rebinding
+ // the pointer using 'pointer_traits'.
+ static_assert(is_same<__node_pointer, typename __node_traits::pointer>::value,
+ "Allocator does not rebind pointers in a sane manner.");
+ typedef __rebind_alloc<__node_traits, __node_base> __node_base_allocator;
+ typedef allocator_traits<__node_base_allocator> __node_base_traits;
+ static_assert(is_same<__node_base_pointer, typename __node_base_traits::pointer>::value,
+ "Allocator does not rebind pointers in a sane manner.");
+
+private:
+ __iter_pointer __begin_node_;
+ __compressed_pair<__end_node_t, __node_allocator> __pair1_;
+ __compressed_pair<size_type, value_compare> __pair3_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __iter_pointer __end_node() _NOEXCEPT {
+ return static_cast<__iter_pointer>(pointer_traits<__end_node_ptr>::pointer_to(__pair1_.first()));
+ }
+ _LIBCPP_HIDE_FROM_ABI __iter_pointer __end_node() const _NOEXCEPT {
+ return static_cast<__iter_pointer>(
+ pointer_traits<__end_node_ptr>::pointer_to(const_cast<__end_node_t&>(__pair1_.first())));
+ }
+ _LIBCPP_HIDE_FROM_ABI __node_allocator& __node_alloc() _NOEXCEPT { return __pair1_.second(); }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI const __node_allocator& __node_alloc() const _NOEXCEPT { return __pair1_.second(); }
+ _LIBCPP_HIDE_FROM_ABI __iter_pointer& __begin_node() _NOEXCEPT { return __begin_node_; }
+ _LIBCPP_HIDE_FROM_ABI const __iter_pointer& __begin_node() const _NOEXCEPT { return __begin_node_; }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI allocator_type __alloc() const _NOEXCEPT { return allocator_type(__node_alloc()); }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI size_type& size() _NOEXCEPT { return __pair3_.first(); }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI const size_type& size() const _NOEXCEPT { return __pair3_.first(); }
+ _LIBCPP_HIDE_FROM_ABI value_compare& value_comp() _NOEXCEPT { return __pair3_.second(); }
+ _LIBCPP_HIDE_FROM_ABI const value_compare& value_comp() const _NOEXCEPT { return __pair3_.second(); }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __root() const _NOEXCEPT {
+ return static_cast<__node_pointer>(__end_node()->__left_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __node_base_pointer* __root_ptr() const _NOEXCEPT {
+ return std::addressof(__end_node()->__left_);
+ }
+
+ typedef __tree_iterator<value_type, __node_pointer, difference_type> iterator;
+ typedef __tree_const_iterator<value_type, __node_pointer, difference_type> const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __tree(const value_compare& __comp) _NOEXCEPT_(
+ is_nothrow_default_constructible<__node_allocator>::value&& is_nothrow_copy_constructible<value_compare>::value);
+ _LIBCPP_HIDE_FROM_ABI explicit __tree(const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI __tree(const value_compare& __comp, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI __tree(const __tree& __t);
+ _LIBCPP_HIDE_FROM_ABI __tree& operator=(const __tree& __t);
+ template <class _ForwardIterator>
+ _LIBCPP_HIDE_FROM_ABI void __assign_unique(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void __assign_multi(_InputIterator __first, _InputIterator __last);
+ _LIBCPP_HIDE_FROM_ABI __tree(__tree&& __t) _NOEXCEPT_(
+ is_nothrow_move_constructible<__node_allocator>::value&& is_nothrow_move_constructible<value_compare>::value);
+ _LIBCPP_HIDE_FROM_ABI __tree(__tree&& __t, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI __tree& operator=(__tree&& __t) _NOEXCEPT_(
+ __node_traits::propagate_on_container_move_assignment::value&& is_nothrow_move_assignable<value_compare>::value&&
+ is_nothrow_move_assignable<__node_allocator>::value);
+ _LIBCPP_HIDE_FROM_ABI ~__tree();
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return iterator(__begin_node()); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return const_iterator(__begin_node()); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return iterator(__end_node()); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return const_iterator(__end_node()); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT {
+ return std::min<size_type>(__node_traits::max_size(__node_alloc()), numeric_limits<difference_type >::max());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(__tree& __t)
+#if _LIBCPP_STD_VER <= 11
+ _NOEXCEPT_(__is_nothrow_swappable_v<value_compare> &&
+ (!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>));
+#else
+ _NOEXCEPT_(__is_nothrow_swappable_v<value_compare>);
+#endif
+
+ template <class _Key, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_key_args(_Key const&, _Args&&... __args);
+ template <class _Key, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_hint_unique_key_args(const_iterator, _Key const&, _Args&&...);
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_impl(_Args&&... __args);
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator __emplace_hint_unique_impl(const_iterator __p, _Args&&... __args);
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator __emplace_multi(_Args&&... __args);
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator __emplace_hint_multi(const_iterator __p, _Args&&... __args);
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique(_Pp&& __x) {
+ return __emplace_unique_extract_key(std::forward<_Pp>(__x), __can_extract_key<_Pp, key_type>());
+ }
+
+ template <class _First,
+ class _Second,
+ __enable_if_t<__can_extract_map_key<_First, key_type, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique(_First&& __f, _Second&& __s) {
+ return __emplace_unique_key_args(__f, std::forward<_First>(__f), std::forward<_Second>(__s));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique(_Args&&... __args) {
+ return __emplace_unique_impl(std::forward<_Args>(__args)...);
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_extract_key(_Pp&& __x, __extract_key_fail_tag) {
+ return __emplace_unique_impl(std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_extract_key(_Pp&& __x, __extract_key_self_tag) {
+ return __emplace_unique_key_args(__x, std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __emplace_unique_extract_key(_Pp&& __x, __extract_key_first_tag) {
+ return __emplace_unique_key_args(__x.first, std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI iterator __emplace_hint_unique(const_iterator __p, _Pp&& __x) {
+ return __emplace_hint_unique_extract_key(__p, std::forward<_Pp>(__x), __can_extract_key<_Pp, key_type>());
+ }
+
+ template <class _First,
+ class _Second,
+ __enable_if_t<__can_extract_map_key<_First, key_type, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator __emplace_hint_unique(const_iterator __p, _First&& __f, _Second&& __s) {
+ return __emplace_hint_unique_key_args(__p, __f, std::forward<_First>(__f), std::forward<_Second>(__s)).first;
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator __emplace_hint_unique(const_iterator __p, _Args&&... __args) {
+ return __emplace_hint_unique_impl(__p, std::forward<_Args>(__args)...);
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI iterator
+ __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_fail_tag) {
+ return __emplace_hint_unique_impl(__p, std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI iterator
+ __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_self_tag) {
+ return __emplace_hint_unique_key_args(__p, __x, std::forward<_Pp>(__x)).first;
+ }
+
+ template <class _Pp>
+ _LIBCPP_HIDE_FROM_ABI iterator
+ __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_first_tag) {
+ return __emplace_hint_unique_key_args(__p, __x.first, std::forward<_Pp>(__x)).first;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __insert_unique(const __container_value_type& __v) {
+ return __emplace_unique_key_args(_NodeTypes::__get_key(__v), __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_unique(const_iterator __p, const __container_value_type& __v) {
+ return __emplace_hint_unique_key_args(__p, _NodeTypes::__get_key(__v), __v).first;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __insert_unique(__container_value_type&& __v) {
+ return __emplace_unique_key_args(_NodeTypes::__get_key(__v), std::move(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_unique(const_iterator __p, __container_value_type&& __v) {
+ return __emplace_hint_unique_key_args(__p, _NodeTypes::__get_key(__v), std::move(__v)).first;
+ }
+
+ template <class _Vp, __enable_if_t<!is_same<__remove_const_ref_t<_Vp>, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __insert_unique(_Vp&& __v) {
+ return __emplace_unique(std::forward<_Vp>(__v));
+ }
+
+ template <class _Vp, __enable_if_t<!is_same<__remove_const_ref_t<_Vp>, __container_value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_unique(const_iterator __p, _Vp&& __v) {
+ return __emplace_hint_unique(__p, std::forward<_Vp>(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_multi(__container_value_type&& __v) {
+ return __emplace_multi(std::move(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_multi(const_iterator __p, __container_value_type&& __v) {
+ return __emplace_hint_multi(__p, std::move(__v));
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_multi(_Vp&& __v) {
+ return __emplace_multi(std::forward<_Vp>(__v));
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_multi(const_iterator __p, _Vp&& __v) {
+ return __emplace_hint_multi(__p, std::forward<_Vp>(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool>
+ __node_assign_unique(const __container_value_type& __v, __node_pointer __dest);
+
+ _LIBCPP_HIDE_FROM_ABI iterator __node_insert_multi(__node_pointer __nd);
+ _LIBCPP_HIDE_FROM_ABI iterator __node_insert_multi(const_iterator __p, __node_pointer __nd);
+
+ _LIBCPP_HIDE_FROM_ABI iterator __remove_node_pointer(__node_pointer) _NOEXCEPT;
+
+#if _LIBCPP_STD_VER >= 17
+ template <class _NodeHandle, class _InsertReturnType>
+ _LIBCPP_HIDE_FROM_ABI _InsertReturnType __node_handle_insert_unique(_NodeHandle&&);
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI iterator __node_handle_insert_unique(const_iterator, _NodeHandle&&);
+ template <class _Tree>
+ _LIBCPP_HIDE_FROM_ABI void __node_handle_merge_unique(_Tree& __source);
+
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI iterator __node_handle_insert_multi(_NodeHandle&&);
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI iterator __node_handle_insert_multi(const_iterator, _NodeHandle&&);
+ template <class _Tree>
+ _LIBCPP_HIDE_FROM_ABI void __node_handle_merge_multi(_Tree& __source);
+
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI _NodeHandle __node_handle_extract(key_type const&);
+ template <class _NodeHandle>
+ _LIBCPP_HIDE_FROM_ABI _NodeHandle __node_handle_extract(const_iterator);
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p);
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __f, const_iterator __l);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type __erase_unique(const _Key& __k);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type __erase_multi(const _Key& __k);
+
+ _LIBCPP_HIDE_FROM_ABI void
+ __insert_node_at(__parent_pointer __parent, __node_base_pointer& __child, __node_base_pointer __new_node) _NOEXCEPT;
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _Key& __v);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _Key& __v) const;
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type __count_unique(const _Key& __k) const;
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI size_type __count_multi(const _Key& __k) const;
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const _Key& __v) {
+ return __lower_bound(__v, __root(), __end_node());
+ }
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI iterator __lower_bound(const _Key& __v, __node_pointer __root, __iter_pointer __result);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const _Key& __v) const {
+ return __lower_bound(__v, __root(), __end_node());
+ }
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI const_iterator
+ __lower_bound(const _Key& __v, __node_pointer __root, __iter_pointer __result) const;
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const _Key& __v) {
+ return __upper_bound(__v, __root(), __end_node());
+ }
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI iterator __upper_bound(const _Key& __v, __node_pointer __root, __iter_pointer __result);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const _Key& __v) const {
+ return __upper_bound(__v, __root(), __end_node());
+ }
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI const_iterator
+ __upper_bound(const _Key& __v, __node_pointer __root, __iter_pointer __result) const;
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> __equal_range_unique(const _Key& __k);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> __equal_range_unique(const _Key& __k) const;
+
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> __equal_range_multi(const _Key& __k);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> __equal_range_multi(const _Key& __k) const;
+
+ typedef __tree_node_destructor<__node_allocator> _Dp;
+ typedef unique_ptr<__node, _Dp> __node_holder;
+
+ _LIBCPP_HIDE_FROM_ABI __node_holder remove(const_iterator __p) _NOEXCEPT;
+
+private:
+ _LIBCPP_HIDE_FROM_ABI __node_base_pointer& __find_leaf_low(__parent_pointer& __parent, const key_type& __v);
+ _LIBCPP_HIDE_FROM_ABI __node_base_pointer& __find_leaf_high(__parent_pointer& __parent, const key_type& __v);
+ _LIBCPP_HIDE_FROM_ABI __node_base_pointer&
+ __find_leaf(const_iterator __hint, __parent_pointer& __parent, const key_type& __v);
+ // FIXME: Make this function const qualified. Unfortunately doing so
+ // breaks existing code which uses non-const callable comparators.
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI __node_base_pointer& __find_equal(__parent_pointer& __parent, const _Key& __v);
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI __node_base_pointer& __find_equal(__parent_pointer& __parent, const _Key& __v) const {
+ return const_cast<__tree*>(this)->__find_equal(__parent, __v);
+ }
+ template <class _Key>
+ _LIBCPP_HIDE_FROM_ABI __node_base_pointer&
+ __find_equal(const_iterator __hint, __parent_pointer& __parent, __node_base_pointer& __dummy, const _Key& __v);
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI __node_holder __construct_node(_Args&&... __args);
+
+ // TODO: Make this _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_HIDDEN void destroy(__node_pointer __nd) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __tree& __t) {
+ __copy_assign_alloc(__t, integral_constant<bool, __node_traits::propagate_on_container_copy_assignment::value>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __tree& __t, true_type) {
+ if (__node_alloc() != __t.__node_alloc())
+ clear();
+ __node_alloc() = __t.__node_alloc();
+ }
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __tree&, false_type) {}
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(__tree& __t, false_type);
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(__tree& __t, true_type) _NOEXCEPT_(
+ is_nothrow_move_assignable<value_compare>::value&& is_nothrow_move_assignable<__node_allocator>::value);
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__tree& __t)
+ _NOEXCEPT_(!__node_traits::propagate_on_container_move_assignment::value ||
+ is_nothrow_move_assignable<__node_allocator>::value) {
+ __move_assign_alloc(__t, integral_constant<bool, __node_traits::propagate_on_container_move_assignment::value>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__tree& __t, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value) {
+ __node_alloc() = std::move(__t.__node_alloc());
+ }
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__tree&, false_type) _NOEXCEPT {}
+
+ struct _DetachedTreeCache {
+ _LIBCPP_HIDE_FROM_ABI explicit _DetachedTreeCache(__tree* __t) _NOEXCEPT
+ : __t_(__t),
+ __cache_root_(__detach_from_tree(__t)) {
+ __advance();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __get() const _NOEXCEPT { return __cache_elem_; }
+
+ _LIBCPP_HIDE_FROM_ABI void __advance() _NOEXCEPT {
+ __cache_elem_ = __cache_root_;
+ if (__cache_root_) {
+ __cache_root_ = __detach_next(__cache_root_);
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~_DetachedTreeCache() {
+ __t_->destroy(__cache_elem_);
+ if (__cache_root_) {
+ while (__cache_root_->__parent_ != nullptr)
+ __cache_root_ = static_cast<__node_pointer>(__cache_root_->__parent_);
+ __t_->destroy(__cache_root_);
+ }
+ }
+
+ _DetachedTreeCache(_DetachedTreeCache const&) = delete;
+ _DetachedTreeCache& operator=(_DetachedTreeCache const&) = delete;
+
+ private:
+ _LIBCPP_HIDE_FROM_ABI static __node_pointer __detach_from_tree(__tree* __t) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI static __node_pointer __detach_next(__node_pointer) _NOEXCEPT;
+
+ __tree* __t_;
+ __node_pointer __cache_root_;
+ __node_pointer __cache_elem_;
+ };
+
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS map;
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS multimap;
+};
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>::__tree(const value_compare& __comp) _NOEXCEPT_(
+ is_nothrow_default_constructible<__node_allocator>::value&& is_nothrow_copy_constructible<value_compare>::value)
+ : __pair3_(0, __comp) {
+ __begin_node() = __end_node();
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>::__tree(const allocator_type& __a)
+ : __begin_node_(__iter_pointer()),
+ __pair1_(__default_init_tag(), __node_allocator(__a)),
+ __pair3_(0, __default_init_tag()) {
+ __begin_node() = __end_node();
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>::__tree(const value_compare& __comp, const allocator_type& __a)
+ : __begin_node_(__iter_pointer()), __pair1_(__default_init_tag(), __node_allocator(__a)), __pair3_(0, __comp) {
+ __begin_node() = __end_node();
+}
+
+// Precondition: size() != 0
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::__node_pointer
+__tree<_Tp, _Compare, _Allocator>::_DetachedTreeCache::__detach_from_tree(__tree* __t) _NOEXCEPT {
+ __node_pointer __cache = static_cast<__node_pointer>(__t->__begin_node());
+ __t->__begin_node() = __t->__end_node();
+ __t->__end_node()->__left_->__parent_ = nullptr;
+ __t->__end_node()->__left_ = nullptr;
+ __t->size() = 0;
+ // __cache->__left_ == nullptr
+ if (__cache->__right_ != nullptr)
+ __cache = static_cast<__node_pointer>(__cache->__right_);
+ // __cache->__left_ == nullptr
+ // __cache->__right_ == nullptr
+ return __cache;
+}
+
+// Precondition: __cache != nullptr
+// __cache->left_ == nullptr
+// __cache->right_ == nullptr
+// This is no longer a red-black tree
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::__node_pointer
+__tree<_Tp, _Compare, _Allocator>::_DetachedTreeCache::__detach_next(__node_pointer __cache) _NOEXCEPT {
+ if (__cache->__parent_ == nullptr)
+ return nullptr;
+ if (std::__tree_is_left_child(static_cast<__node_base_pointer>(__cache))) {
+ __cache->__parent_->__left_ = nullptr;
+ __cache = static_cast<__node_pointer>(__cache->__parent_);
+ if (__cache->__right_ == nullptr)
+ return __cache;
+ return static_cast<__node_pointer>(std::__tree_leaf(__cache->__right_));
+ }
+ // __cache is right child
+ __cache->__parent_unsafe()->__right_ = nullptr;
+ __cache = static_cast<__node_pointer>(__cache->__parent_);
+ if (__cache->__left_ == nullptr)
+ return __cache;
+ return static_cast<__node_pointer>(std::__tree_leaf(__cache->__left_));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>& __tree<_Tp, _Compare, _Allocator>::operator=(const __tree& __t) {
+ if (this != std::addressof(__t)) {
+ value_comp() = __t.value_comp();
+ __copy_assign_alloc(__t);
+ __assign_multi(__t.begin(), __t.end());
+ }
+ return *this;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _ForwardIterator>
+void __tree<_Tp, _Compare, _Allocator>::__assign_unique(_ForwardIterator __first, _ForwardIterator __last) {
+ typedef iterator_traits<_ForwardIterator> _ITraits;
+ typedef typename _ITraits::value_type _ItValueType;
+ static_assert(is_same<_ItValueType, __container_value_type>::value,
+ "__assign_unique may only be called with the containers value type");
+ static_assert(
+ __has_forward_iterator_category<_ForwardIterator>::value, "__assign_unique requires a forward iterator");
+ if (size() != 0) {
+ _DetachedTreeCache __cache(this);
+ for (; __cache.__get() != nullptr && __first != __last; ++__first) {
+ if (__node_assign_unique(*__first, __cache.__get()).second)
+ __cache.__advance();
+ }
+ }
+ for (; __first != __last; ++__first)
+ __insert_unique(*__first);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _InputIterator>
+void __tree<_Tp, _Compare, _Allocator>::__assign_multi(_InputIterator __first, _InputIterator __last) {
+ typedef iterator_traits<_InputIterator> _ITraits;
+ typedef typename _ITraits::value_type _ItValueType;
+ static_assert(
+ (is_same<_ItValueType, __container_value_type>::value || is_same<_ItValueType, __node_value_type>::value),
+ "__assign_multi may only be called with the containers value type"
+ " or the nodes value type");
+ if (size() != 0) {
+ _DetachedTreeCache __cache(this);
+ for (; __cache.__get() && __first != __last; ++__first) {
+ __cache.__get()->__value_ = *__first;
+ __node_insert_multi(__cache.__get());
+ __cache.__advance();
+ }
+ }
+ for (; __first != __last; ++__first)
+ __insert_multi(_NodeTypes::__get_value(*__first));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>::__tree(const __tree& __t)
+ : __begin_node_(__iter_pointer()),
+ __pair1_(__default_init_tag(), __node_traits::select_on_container_copy_construction(__t.__node_alloc())),
+ __pair3_(0, __t.value_comp()) {
+ __begin_node() = __end_node();
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>::__tree(__tree&& __t) _NOEXCEPT_(
+ is_nothrow_move_constructible<__node_allocator>::value&& is_nothrow_move_constructible<value_compare>::value)
+ : __begin_node_(std::move(__t.__begin_node_)),
+ __pair1_(std::move(__t.__pair1_)),
+ __pair3_(std::move(__t.__pair3_)) {
+ if (size() == 0)
+ __begin_node() = __end_node();
+ else {
+ __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
+ __t.__begin_node() = __t.__end_node();
+ __t.__end_node()->__left_ = nullptr;
+ __t.size() = 0;
+ }
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>::__tree(__tree&& __t, const allocator_type& __a)
+ : __pair1_(__default_init_tag(), __node_allocator(__a)), __pair3_(0, std::move(__t.value_comp())) {
+ if (__a == __t.__alloc()) {
+ if (__t.size() == 0)
+ __begin_node() = __end_node();
+ else {
+ __begin_node() = __t.__begin_node();
+ __end_node()->__left_ = __t.__end_node()->__left_;
+ __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
+ size() = __t.size();
+ __t.__begin_node() = __t.__end_node();
+ __t.__end_node()->__left_ = nullptr;
+ __t.size() = 0;
+ }
+ } else {
+ __begin_node() = __end_node();
+ }
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+void __tree<_Tp, _Compare, _Allocator>::__move_assign(__tree& __t, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<value_compare>::value&& is_nothrow_move_assignable<__node_allocator>::value) {
+ destroy(static_cast<__node_pointer>(__end_node()->__left_));
+ __begin_node_ = __t.__begin_node_;
+ __pair1_.first() = __t.__pair1_.first();
+ __move_assign_alloc(__t);
+ __pair3_ = std::move(__t.__pair3_);
+ if (size() == 0)
+ __begin_node() = __end_node();
+ else {
+ __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
+ __t.__begin_node() = __t.__end_node();
+ __t.__end_node()->__left_ = nullptr;
+ __t.size() = 0;
+ }
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+void __tree<_Tp, _Compare, _Allocator>::__move_assign(__tree& __t, false_type) {
+ if (__node_alloc() == __t.__node_alloc())
+ __move_assign(__t, true_type());
+ else {
+ value_comp() = std::move(__t.value_comp());
+ const_iterator __e = end();
+ if (size() != 0) {
+ _DetachedTreeCache __cache(this);
+ while (__cache.__get() != nullptr && __t.size() != 0) {
+ __cache.__get()->__value_ = std::move(__t.remove(__t.begin())->__value_);
+ __node_insert_multi(__cache.__get());
+ __cache.__advance();
+ }
+ }
+ while (__t.size() != 0)
+ __insert_multi(__e, _NodeTypes::__move(__t.remove(__t.begin())->__value_));
+ }
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>& __tree<_Tp, _Compare, _Allocator>::operator=(__tree&& __t) _NOEXCEPT_(
+ __node_traits::propagate_on_container_move_assignment::value&& is_nothrow_move_assignable<value_compare>::value&&
+ is_nothrow_move_assignable<__node_allocator>::value)
+
+{
+ __move_assign(__t, integral_constant<bool, __node_traits::propagate_on_container_move_assignment::value>());
+ return *this;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+__tree<_Tp, _Compare, _Allocator>::~__tree() {
+ static_assert(is_copy_constructible<value_compare>::value, "Comparator must be copy-constructible.");
+ destroy(__root());
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+void __tree<_Tp, _Compare, _Allocator>::destroy(__node_pointer __nd) _NOEXCEPT {
+ if (__nd != nullptr) {
+ destroy(static_cast<__node_pointer>(__nd->__left_));
+ destroy(static_cast<__node_pointer>(__nd->__right_));
+ __node_allocator& __na = __node_alloc();
+ __node_traits::destroy(__na, _NodeTypes::__get_ptr(__nd->__value_));
+ __node_traits::deallocate(__na, __nd, 1);
+ }
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+void __tree<_Tp, _Compare, _Allocator>::swap(__tree& __t)
+#if _LIBCPP_STD_VER <= 11
+ _NOEXCEPT_(__is_nothrow_swappable_v<value_compare> &&
+ (!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>))
+#else
+ _NOEXCEPT_(__is_nothrow_swappable_v<value_compare>)
+#endif
+{
+ using std::swap;
+ swap(__begin_node_, __t.__begin_node_);
+ swap(__pair1_.first(), __t.__pair1_.first());
+ std::__swap_allocator(__node_alloc(), __t.__node_alloc());
+ __pair3_.swap(__t.__pair3_);
+ if (size() == 0)
+ __begin_node() = __end_node();
+ else
+ __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
+ if (__t.size() == 0)
+ __t.__begin_node() = __t.__end_node();
+ else
+ __t.__end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__t.__end_node());
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+void __tree<_Tp, _Compare, _Allocator>::clear() _NOEXCEPT {
+ destroy(__root());
+ size() = 0;
+ __begin_node() = __end_node();
+ __end_node()->__left_ = nullptr;
+}
+
+// Find lower_bound place to insert
+// Set __parent to parent of null leaf
+// Return reference to null leaf
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
+__tree<_Tp, _Compare, _Allocator>::__find_leaf_low(__parent_pointer& __parent, const key_type& __v) {
+ __node_pointer __nd = __root();
+ if (__nd != nullptr) {
+ while (true) {
+ if (value_comp()(__nd->__value_, __v)) {
+ if (__nd->__right_ != nullptr)
+ __nd = static_cast<__node_pointer>(__nd->__right_);
+ else {
+ __parent = static_cast<__parent_pointer>(__nd);
+ return __nd->__right_;
+ }
+ } else {
+ if (__nd->__left_ != nullptr)
+ __nd = static_cast<__node_pointer>(__nd->__left_);
+ else {
+ __parent = static_cast<__parent_pointer>(__nd);
+ return __parent->__left_;
+ }
+ }
+ }
+ }
+ __parent = static_cast<__parent_pointer>(__end_node());
+ return __parent->__left_;
+}
+
+// Find upper_bound place to insert
+// Set __parent to parent of null leaf
+// Return reference to null leaf
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
+__tree<_Tp, _Compare, _Allocator>::__find_leaf_high(__parent_pointer& __parent, const key_type& __v) {
+ __node_pointer __nd = __root();
+ if (__nd != nullptr) {
+ while (true) {
+ if (value_comp()(__v, __nd->__value_)) {
+ if (__nd->__left_ != nullptr)
+ __nd = static_cast<__node_pointer>(__nd->__left_);
+ else {
+ __parent = static_cast<__parent_pointer>(__nd);
+ return __parent->__left_;
+ }
+ } else {
+ if (__nd->__right_ != nullptr)
+ __nd = static_cast<__node_pointer>(__nd->__right_);
+ else {
+ __parent = static_cast<__parent_pointer>(__nd);
+ return __nd->__right_;
+ }
+ }
+ }
+ }
+ __parent = static_cast<__parent_pointer>(__end_node());
+ return __parent->__left_;
+}
+
+// Find leaf place to insert closest to __hint
+// First check prior to __hint.
+// Next check after __hint.
+// Next do O(log N) search.
+// Set __parent to parent of null leaf
+// Return reference to null leaf
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
+__tree<_Tp, _Compare, _Allocator>::__find_leaf(const_iterator __hint, __parent_pointer& __parent, const key_type& __v) {
+ if (__hint == end() || !value_comp()(*__hint, __v)) // check before
+ {
+ // __v <= *__hint
+ const_iterator __prior = __hint;
+ if (__prior == begin() || !value_comp()(__v, *--__prior)) {
+ // *prev(__hint) <= __v <= *__hint
+ if (__hint.__ptr_->__left_ == nullptr) {
+ __parent = static_cast<__parent_pointer>(__hint.__ptr_);
+ return __parent->__left_;
+ } else {
+ __parent = static_cast<__parent_pointer>(__prior.__ptr_);
+ return static_cast<__node_base_pointer>(__prior.__ptr_)->__right_;
+ }
+ }
+ // __v < *prev(__hint)
+ return __find_leaf_high(__parent, __v);
+ }
+ // else __v > *__hint
+ return __find_leaf_low(__parent, __v);
+}
+
+// Find place to insert if __v doesn't exist
+// Set __parent to parent of null leaf
+// Return reference to null leaf
+// If __v exists, set parent to node of __v and return reference to node of __v
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
+__tree<_Tp, _Compare, _Allocator>::__find_equal(__parent_pointer& __parent, const _Key& __v) {
+ __node_pointer __nd = __root();
+ __node_base_pointer* __nd_ptr = __root_ptr();
+ if (__nd != nullptr) {
+ while (true) {
+ if (value_comp()(__v, __nd->__value_)) {
+ if (__nd->__left_ != nullptr) {
+ __nd_ptr = std::addressof(__nd->__left_);
+ __nd = static_cast<__node_pointer>(__nd->__left_);
+ } else {
+ __parent = static_cast<__parent_pointer>(__nd);
+ return __parent->__left_;
+ }
+ } else if (value_comp()(__nd->__value_, __v)) {
+ if (__nd->__right_ != nullptr) {
+ __nd_ptr = std::addressof(__nd->__right_);
+ __nd = static_cast<__node_pointer>(__nd->__right_);
+ } else {
+ __parent = static_cast<__parent_pointer>(__nd);
+ return __nd->__right_;
+ }
+ } else {
+ __parent = static_cast<__parent_pointer>(__nd);
+ return *__nd_ptr;
+ }
+ }
+ }
+ __parent = static_cast<__parent_pointer>(__end_node());
+ return __parent->__left_;
+}
+
+// Find place to insert if __v doesn't exist
+// First check prior to __hint.
+// Next check after __hint.
+// Next do O(log N) search.
+// Set __parent to parent of null leaf
+// Return reference to null leaf
+// If __v exists, set parent to node of __v and return reference to node of __v
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer& __tree<_Tp, _Compare, _Allocator>::__find_equal(
+ const_iterator __hint, __parent_pointer& __parent, __node_base_pointer& __dummy, const _Key& __v) {
+ if (__hint == end() || value_comp()(__v, *__hint)) // check before
+ {
+ // __v < *__hint
+ const_iterator __prior = __hint;
+ if (__prior == begin() || value_comp()(*--__prior, __v)) {
+ // *prev(__hint) < __v < *__hint
+ if (__hint.__ptr_->__left_ == nullptr) {
+ __parent = static_cast<__parent_pointer>(__hint.__ptr_);
+ return __parent->__left_;
+ } else {
+ __parent = static_cast<__parent_pointer>(__prior.__ptr_);
+ return static_cast<__node_base_pointer>(__prior.__ptr_)->__right_;
+ }
+ }
+ // __v <= *prev(__hint)
+ return __find_equal(__parent, __v);
+ } else if (value_comp()(*__hint, __v)) // check after
+ {
+ // *__hint < __v
+ const_iterator __next = std::next(__hint);
+ if (__next == end() || value_comp()(__v, *__next)) {
+ // *__hint < __v < *std::next(__hint)
+ if (__hint.__get_np()->__right_ == nullptr) {
+ __parent = static_cast<__parent_pointer>(__hint.__ptr_);
+ return static_cast<__node_base_pointer>(__hint.__ptr_)->__right_;
+ } else {
+ __parent = static_cast<__parent_pointer>(__next.__ptr_);
+ return __parent->__left_;
+ }
+ }
+ // *next(__hint) <= __v
+ return __find_equal(__parent, __v);
+ }
+ // else __v == *__hint
+ __parent = static_cast<__parent_pointer>(__hint.__ptr_);
+ __dummy = static_cast<__node_base_pointer>(__hint.__ptr_);
+ return __dummy;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+void __tree<_Tp, _Compare, _Allocator>::__insert_node_at(
+ __parent_pointer __parent, __node_base_pointer& __child, __node_base_pointer __new_node) _NOEXCEPT {
+ __new_node->__left_ = nullptr;
+ __new_node->__right_ = nullptr;
+ __new_node->__parent_ = __parent;
+ // __new_node->__is_black_ is initialized in __tree_balance_after_insert
+ __child = __new_node;
+ if (__begin_node()->__left_ != nullptr)
+ __begin_node() = static_cast<__iter_pointer>(__begin_node()->__left_);
+ std::__tree_balance_after_insert(__end_node()->__left_, __child);
+ ++size();
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key, class... _Args>
+pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
+__tree<_Tp, _Compare, _Allocator>::__emplace_unique_key_args(_Key const& __k, _Args&&... __args) {
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_equal(__parent, __k);
+ __node_pointer __r = static_cast<__node_pointer>(__child);
+ bool __inserted = false;
+ if (__child == nullptr) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
+ __r = __h.release();
+ __inserted = true;
+ }
+ return pair<iterator, bool>(iterator(__r), __inserted);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key, class... _Args>
+pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
+__tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique_key_args(
+ const_iterator __p, _Key const& __k, _Args&&... __args) {
+ __parent_pointer __parent;
+ __node_base_pointer __dummy;
+ __node_base_pointer& __child = __find_equal(__p, __parent, __dummy, __k);
+ __node_pointer __r = static_cast<__node_pointer>(__child);
+ bool __inserted = false;
+ if (__child == nullptr) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
+ __r = __h.release();
+ __inserted = true;
+ }
+ return pair<iterator, bool>(iterator(__r), __inserted);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class... _Args>
+typename __tree<_Tp, _Compare, _Allocator>::__node_holder
+__tree<_Tp, _Compare, _Allocator>::__construct_node(_Args&&... __args) {
+ static_assert(!__is_tree_value_type<_Args...>::value, "Cannot construct from __value_type");
+ __node_allocator& __na = __node_alloc();
+ __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
+ __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_), std::forward<_Args>(__args)...);
+ __h.get_deleter().__value_constructed = true;
+ return __h;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class... _Args>
+pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
+__tree<_Tp, _Compare, _Allocator>::__emplace_unique_impl(_Args&&... __args) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_equal(__parent, __h->__value_);
+ __node_pointer __r = static_cast<__node_pointer>(__child);
+ bool __inserted = false;
+ if (__child == nullptr) {
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
+ __r = __h.release();
+ __inserted = true;
+ }
+ return pair<iterator, bool>(iterator(__r), __inserted);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class... _Args>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique_impl(const_iterator __p, _Args&&... __args) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ __parent_pointer __parent;
+ __node_base_pointer __dummy;
+ __node_base_pointer& __child = __find_equal(__p, __parent, __dummy, __h->__value_);
+ __node_pointer __r = static_cast<__node_pointer>(__child);
+ if (__child == nullptr) {
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
+ __r = __h.release();
+ }
+ return iterator(__r);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class... _Args>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__emplace_multi(_Args&&... __args) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__h->__value_));
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
+ return iterator(static_cast<__node_pointer>(__h.release()));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class... _Args>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__emplace_hint_multi(const_iterator __p, _Args&&... __args) {
+ __node_holder __h = __construct_node(std::forward<_Args>(__args)...);
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_leaf(__p, __parent, _NodeTypes::__get_key(__h->__value_));
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
+ return iterator(static_cast<__node_pointer>(__h.release()));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
+__tree<_Tp, _Compare, _Allocator>::__node_assign_unique(const __container_value_type& __v, __node_pointer __nd) {
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_equal(__parent, _NodeTypes::__get_key(__v));
+ __node_pointer __r = static_cast<__node_pointer>(__child);
+ bool __inserted = false;
+ if (__child == nullptr) {
+ __nd->__value_ = __v;
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
+ __r = __nd;
+ __inserted = true;
+ }
+ return pair<iterator, bool>(iterator(__r), __inserted);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__node_insert_multi(__node_pointer __nd) {
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__nd->__value_));
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
+ return iterator(__nd);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__node_insert_multi(const_iterator __p, __node_pointer __nd) {
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_leaf(__p, __parent, _NodeTypes::__get_key(__nd->__value_));
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
+ return iterator(__nd);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__remove_node_pointer(__node_pointer __ptr) _NOEXCEPT {
+ iterator __r(__ptr);
+ ++__r;
+ if (__begin_node() == __ptr)
+ __begin_node() = __r.__ptr_;
+ --size();
+ std::__tree_remove(__end_node()->__left_, static_cast<__node_base_pointer>(__ptr));
+ return __r;
+}
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class _Compare, class _Allocator>
+template <class _NodeHandle, class _InsertReturnType>
+_LIBCPP_HIDE_FROM_ABI _InsertReturnType
+__tree<_Tp, _Compare, _Allocator>::__node_handle_insert_unique(_NodeHandle&& __nh) {
+ if (__nh.empty())
+ return _InsertReturnType{end(), false, _NodeHandle()};
+
+ __node_pointer __ptr = __nh.__ptr_;
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_equal(__parent, __ptr->__value_);
+ if (__child != nullptr)
+ return _InsertReturnType{iterator(static_cast<__node_pointer>(__child)), false, std::move(__nh)};
+
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__ptr));
+ __nh.__release_ptr();
+ return _InsertReturnType{iterator(__ptr), true, _NodeHandle()};
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__node_handle_insert_unique(const_iterator __hint, _NodeHandle&& __nh) {
+ if (__nh.empty())
+ return end();
+
+ __node_pointer __ptr = __nh.__ptr_;
+ __parent_pointer __parent;
+ __node_base_pointer __dummy;
+ __node_base_pointer& __child = __find_equal(__hint, __parent, __dummy, __ptr->__value_);
+ __node_pointer __r = static_cast<__node_pointer>(__child);
+ if (__child == nullptr) {
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__ptr));
+ __r = __ptr;
+ __nh.__release_ptr();
+ }
+ return iterator(__r);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI _NodeHandle __tree<_Tp, _Compare, _Allocator>::__node_handle_extract(key_type const& __key) {
+ iterator __it = find(__key);
+ if (__it == end())
+ return _NodeHandle();
+ return __node_handle_extract<_NodeHandle>(__it);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI _NodeHandle __tree<_Tp, _Compare, _Allocator>::__node_handle_extract(const_iterator __p) {
+ __node_pointer __np = __p.__get_np();
+ __remove_node_pointer(__np);
+ return _NodeHandle(__np, __alloc());
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Tree>
+_LIBCPP_HIDE_FROM_ABI void __tree<_Tp, _Compare, _Allocator>::__node_handle_merge_unique(_Tree& __source) {
+ static_assert(is_same<typename _Tree::__node_pointer, __node_pointer>::value, "");
+
+ for (typename _Tree::iterator __i = __source.begin(); __i != __source.end();) {
+ __node_pointer __src_ptr = __i.__get_np();
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_equal(__parent, _NodeTypes::__get_key(__src_ptr->__value_));
+ ++__i;
+ if (__child != nullptr)
+ continue;
+ __source.__remove_node_pointer(__src_ptr);
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__src_ptr));
+ }
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__node_handle_insert_multi(_NodeHandle&& __nh) {
+ if (__nh.empty())
+ return end();
+ __node_pointer __ptr = __nh.__ptr_;
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__ptr->__value_));
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__ptr));
+ __nh.__release_ptr();
+ return iterator(__ptr);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _NodeHandle>
+_LIBCPP_HIDE_FROM_ABI typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__node_handle_insert_multi(const_iterator __hint, _NodeHandle&& __nh) {
+ if (__nh.empty())
+ return end();
+
+ __node_pointer __ptr = __nh.__ptr_;
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_leaf(__hint, __parent, _NodeTypes::__get_key(__ptr->__value_));
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__ptr));
+ __nh.__release_ptr();
+ return iterator(__ptr);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Tree>
+_LIBCPP_HIDE_FROM_ABI void __tree<_Tp, _Compare, _Allocator>::__node_handle_merge_multi(_Tree& __source) {
+ static_assert(is_same<typename _Tree::__node_pointer, __node_pointer>::value, "");
+
+ for (typename _Tree::iterator __i = __source.begin(); __i != __source.end();) {
+ __node_pointer __src_ptr = __i.__get_np();
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__src_ptr->__value_));
+ ++__i;
+ __source.__remove_node_pointer(__src_ptr);
+ __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__src_ptr));
+ }
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::iterator __tree<_Tp, _Compare, _Allocator>::erase(const_iterator __p) {
+ __node_pointer __np = __p.__get_np();
+ iterator __r = __remove_node_pointer(__np);
+ __node_allocator& __na = __node_alloc();
+ __node_traits::destroy(__na, _NodeTypes::__get_ptr(const_cast<__node_value_type&>(*__p)));
+ __node_traits::deallocate(__na, __np, 1);
+ return __r;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::erase(const_iterator __f, const_iterator __l) {
+ while (__f != __l)
+ __f = erase(__f);
+ return iterator(__l.__ptr_);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::size_type
+__tree<_Tp, _Compare, _Allocator>::__erase_unique(const _Key& __k) {
+ iterator __i = find(__k);
+ if (__i == end())
+ return 0;
+ erase(__i);
+ return 1;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::size_type
+__tree<_Tp, _Compare, _Allocator>::__erase_multi(const _Key& __k) {
+ pair<iterator, iterator> __p = __equal_range_multi(__k);
+ size_type __r = 0;
+ for (; __p.first != __p.second; ++__r)
+ __p.first = erase(__p.first);
+ return __r;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::iterator __tree<_Tp, _Compare, _Allocator>::find(const _Key& __v) {
+ iterator __p = __lower_bound(__v, __root(), __end_node());
+ if (__p != end() && !value_comp()(__v, *__p))
+ return __p;
+ return end();
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::const_iterator
+__tree<_Tp, _Compare, _Allocator>::find(const _Key& __v) const {
+ const_iterator __p = __lower_bound(__v, __root(), __end_node());
+ if (__p != end() && !value_comp()(__v, *__p))
+ return __p;
+ return end();
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::size_type
+__tree<_Tp, _Compare, _Allocator>::__count_unique(const _Key& __k) const {
+ __node_pointer __rt = __root();
+ while (__rt != nullptr) {
+ if (value_comp()(__k, __rt->__value_)) {
+ __rt = static_cast<__node_pointer>(__rt->__left_);
+ } else if (value_comp()(__rt->__value_, __k))
+ __rt = static_cast<__node_pointer>(__rt->__right_);
+ else
+ return 1;
+ }
+ return 0;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::size_type
+__tree<_Tp, _Compare, _Allocator>::__count_multi(const _Key& __k) const {
+ __iter_pointer __result = __end_node();
+ __node_pointer __rt = __root();
+ while (__rt != nullptr) {
+ if (value_comp()(__k, __rt->__value_)) {
+ __result = static_cast<__iter_pointer>(__rt);
+ __rt = static_cast<__node_pointer>(__rt->__left_);
+ } else if (value_comp()(__rt->__value_, __k))
+ __rt = static_cast<__node_pointer>(__rt->__right_);
+ else
+ return std::distance(
+ __lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
+ __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result));
+ }
+ return 0;
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__lower_bound(const _Key& __v, __node_pointer __root, __iter_pointer __result) {
+ while (__root != nullptr) {
+ if (!value_comp()(__root->__value_, __v)) {
+ __result = static_cast<__iter_pointer>(__root);
+ __root = static_cast<__node_pointer>(__root->__left_);
+ } else
+ __root = static_cast<__node_pointer>(__root->__right_);
+ }
+ return iterator(__result);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::const_iterator __tree<_Tp, _Compare, _Allocator>::__lower_bound(
+ const _Key& __v, __node_pointer __root, __iter_pointer __result) const {
+ while (__root != nullptr) {
+ if (!value_comp()(__root->__value_, __v)) {
+ __result = static_cast<__iter_pointer>(__root);
+ __root = static_cast<__node_pointer>(__root->__left_);
+ } else
+ __root = static_cast<__node_pointer>(__root->__right_);
+ }
+ return const_iterator(__result);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::iterator
+__tree<_Tp, _Compare, _Allocator>::__upper_bound(const _Key& __v, __node_pointer __root, __iter_pointer __result) {
+ while (__root != nullptr) {
+ if (value_comp()(__v, __root->__value_)) {
+ __result = static_cast<__iter_pointer>(__root);
+ __root = static_cast<__node_pointer>(__root->__left_);
+ } else
+ __root = static_cast<__node_pointer>(__root->__right_);
+ }
+ return iterator(__result);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+typename __tree<_Tp, _Compare, _Allocator>::const_iterator __tree<_Tp, _Compare, _Allocator>::__upper_bound(
+ const _Key& __v, __node_pointer __root, __iter_pointer __result) const {
+ while (__root != nullptr) {
+ if (value_comp()(__v, __root->__value_)) {
+ __result = static_cast<__iter_pointer>(__root);
+ __root = static_cast<__node_pointer>(__root->__left_);
+ } else
+ __root = static_cast<__node_pointer>(__root->__right_);
+ }
+ return const_iterator(__result);
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, typename __tree<_Tp, _Compare, _Allocator>::iterator>
+__tree<_Tp, _Compare, _Allocator>::__equal_range_unique(const _Key& __k) {
+ typedef pair<iterator, iterator> _Pp;
+ __iter_pointer __result = __end_node();
+ __node_pointer __rt = __root();
+ while (__rt != nullptr) {
+ if (value_comp()(__k, __rt->__value_)) {
+ __result = static_cast<__iter_pointer>(__rt);
+ __rt = static_cast<__node_pointer>(__rt->__left_);
+ } else if (value_comp()(__rt->__value_, __k))
+ __rt = static_cast<__node_pointer>(__rt->__right_);
+ else
+ return _Pp(iterator(__rt),
+ iterator(__rt->__right_ != nullptr ? static_cast<__iter_pointer>(std::__tree_min(__rt->__right_))
+ : __result));
+ }
+ return _Pp(iterator(__result), iterator(__result));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+pair<typename __tree<_Tp, _Compare, _Allocator>::const_iterator,
+ typename __tree<_Tp, _Compare, _Allocator>::const_iterator>
+__tree<_Tp, _Compare, _Allocator>::__equal_range_unique(const _Key& __k) const {
+ typedef pair<const_iterator, const_iterator> _Pp;
+ __iter_pointer __result = __end_node();
+ __node_pointer __rt = __root();
+ while (__rt != nullptr) {
+ if (value_comp()(__k, __rt->__value_)) {
+ __result = static_cast<__iter_pointer>(__rt);
+ __rt = static_cast<__node_pointer>(__rt->__left_);
+ } else if (value_comp()(__rt->__value_, __k))
+ __rt = static_cast<__node_pointer>(__rt->__right_);
+ else
+ return _Pp(
+ const_iterator(__rt),
+ const_iterator(
+ __rt->__right_ != nullptr ? static_cast<__iter_pointer>(std::__tree_min(__rt->__right_)) : __result));
+ }
+ return _Pp(const_iterator(__result), const_iterator(__result));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, typename __tree<_Tp, _Compare, _Allocator>::iterator>
+__tree<_Tp, _Compare, _Allocator>::__equal_range_multi(const _Key& __k) {
+ typedef pair<iterator, iterator> _Pp;
+ __iter_pointer __result = __end_node();
+ __node_pointer __rt = __root();
+ while (__rt != nullptr) {
+ if (value_comp()(__k, __rt->__value_)) {
+ __result = static_cast<__iter_pointer>(__rt);
+ __rt = static_cast<__node_pointer>(__rt->__left_);
+ } else if (value_comp()(__rt->__value_, __k))
+ __rt = static_cast<__node_pointer>(__rt->__right_);
+ else
+ return _Pp(__lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
+ __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result));
+ }
+ return _Pp(iterator(__result), iterator(__result));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+template <class _Key>
+pair<typename __tree<_Tp, _Compare, _Allocator>::const_iterator,
+ typename __tree<_Tp, _Compare, _Allocator>::const_iterator>
+__tree<_Tp, _Compare, _Allocator>::__equal_range_multi(const _Key& __k) const {
+ typedef pair<const_iterator, const_iterator> _Pp;
+ __iter_pointer __result = __end_node();
+ __node_pointer __rt = __root();
+ while (__rt != nullptr) {
+ if (value_comp()(__k, __rt->__value_)) {
+ __result = static_cast<__iter_pointer>(__rt);
+ __rt = static_cast<__node_pointer>(__rt->__left_);
+ } else if (value_comp()(__rt->__value_, __k))
+ __rt = static_cast<__node_pointer>(__rt->__right_);
+ else
+ return _Pp(__lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
+ __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result));
+ }
+ return _Pp(const_iterator(__result), const_iterator(__result));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+typename __tree<_Tp, _Compare, _Allocator>::__node_holder
+__tree<_Tp, _Compare, _Allocator>::remove(const_iterator __p) _NOEXCEPT {
+ __node_pointer __np = __p.__get_np();
+ if (__begin_node() == __p.__ptr_) {
+ if (__np->__right_ != nullptr)
+ __begin_node() = static_cast<__iter_pointer>(__np->__right_);
+ else
+ __begin_node() = static_cast<__iter_pointer>(__np->__parent_);
+ }
+ --size();
+ std::__tree_remove(__end_node()->__left_, static_cast<__node_base_pointer>(__np));
+ return __node_holder(__np, _Dp(__node_alloc(), true));
+}
+
+template <class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void swap(__tree<_Tp, _Compare, _Allocator>& __x, __tree<_Tp, _Compare, _Allocator>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___TREE
diff --git a/libcxx/include/__cxx03/__tuple/find_index.h b/libcxx/include/__cxx03/__tuple/find_index.h
new file mode 100644
index 00000000000000..133b00419d0c6c
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/find_index.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_FIND_INDEX_H
+#define _LIBCPP___TUPLE_FIND_INDEX_H
+
+#include <__config>
+#include <__type_traits/is_same.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __find_detail {
+
+static constexpr size_t __not_found = static_cast<size_t>(-1);
+static constexpr size_t __ambiguous = __not_found - 1;
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr size_t __find_idx_return(size_t __curr_i, size_t __res, bool __matches) {
+ return !__matches ? __res : (__res == __not_found ? __curr_i : __ambiguous);
+}
+
+template <size_t _Nx>
+inline _LIBCPP_HIDE_FROM_ABI constexpr size_t __find_idx(size_t __i, const bool (&__matches)[_Nx]) {
+ return __i == _Nx
+ ? __not_found
+ : __find_detail::__find_idx_return(__i, __find_detail::__find_idx(__i + 1, __matches), __matches[__i]);
+}
+
+template <class _T1, class... _Args>
+struct __find_exactly_one_checked {
+ static constexpr bool __matches[sizeof...(_Args)] = {is_same<_T1, _Args>::value...};
+ static constexpr size_t value = __find_detail::__find_idx(0, __matches);
+ static_assert(value != __not_found, "type not found in type list");
+ static_assert(value != __ambiguous, "type occurs more than once in type list");
+};
+
+template <class _T1>
+struct __find_exactly_one_checked<_T1> {
+ static_assert(!is_same<_T1, _T1>::value, "type not in empty type list");
+};
+
+} // namespace __find_detail
+
+template <typename _T1, typename... _Args>
+struct __find_exactly_one_t : public __find_detail::__find_exactly_one_checked<_T1, _Args...> {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 14
+
+#endif // _LIBCPP___TUPLE_FIND_INDEX_H
diff --git a/libcxx/include/__cxx03/__tuple/ignore.h b/libcxx/include/__cxx03/__tuple/ignore.h
new file mode 100644
index 00000000000000..43cce5387411be
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/ignore.h
@@ -0,0 +1,39 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_IGNORE_H
+#define _LIBCPP___TUPLE_IGNORE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __ignore_type {
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const __ignore_type& operator=(const _Tp&) const noexcept {
+ return *this;
+ }
+};
+
+# if _LIBCPP_STD_VER >= 17
+inline constexpr __ignore_type ignore;
+# else
+constexpr __ignore_type ignore;
+# endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CXX03_LANG
+
+#endif // _LIBCPP___TUPLE_IGNORE_H
diff --git a/libcxx/include/__cxx03/__tuple/make_tuple_types.h b/libcxx/include/__cxx03/__tuple/make_tuple_types.h
new file mode 100644
index 00000000000000..9e0fefae2f2f58
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/make_tuple_types.h
@@ -0,0 +1,80 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_MAKE_TUPLE_TYPES_H
+#define _LIBCPP___TUPLE_MAKE_TUPLE_TYPES_H
+
+#include <__config>
+#include <__fwd/array.h>
+#include <__fwd/tuple.h>
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_indices.h>
+#include <__tuple/tuple_size.h>
+#include <__tuple/tuple_types.h>
+#include <__type_traits/copy_cvref.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_reference.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// __make_tuple_types<_Tuple<_Types...>, _Ep, _Sp>::type is a
+// __tuple_types<_Types...> using only those _Types in the range [_Sp, _Ep).
+// _Sp defaults to 0 and _Ep defaults to tuple_size<_Tuple>. If _Tuple is a
+// lvalue_reference type, then __tuple_types<_Types&...> is the result.
+
+template <class _TupleTypes, class _TupleIndices>
+struct __make_tuple_types_flat;
+
+template <template <class...> class _Tuple, class... _Types, size_t... _Idx>
+struct __make_tuple_types_flat<_Tuple<_Types...>, __tuple_indices<_Idx...>> {
+ // Specialization for pair, tuple, and __tuple_types
+ template <class _Tp>
+ using __apply_quals _LIBCPP_NODEBUG = __tuple_types<__copy_cvref_t<_Tp, __type_pack_element<_Idx, _Types...>>...>;
+};
+
+template <class _Vt, size_t _Np, size_t... _Idx>
+struct __make_tuple_types_flat<array<_Vt, _Np>, __tuple_indices<_Idx...>> {
+ template <size_t>
+ using __value_type = _Vt;
+ template <class _Tp>
+ using __apply_quals = __tuple_types<__copy_cvref_t<_Tp, __value_type<_Idx>>...>;
+};
+
+template <class _Tp,
+ size_t _Ep = tuple_size<__libcpp_remove_reference_t<_Tp> >::value,
+ size_t _Sp = 0,
+ bool _SameSize = (_Ep == tuple_size<__libcpp_remove_reference_t<_Tp> >::value)>
+struct __make_tuple_types {
+ static_assert(_Sp <= _Ep, "__make_tuple_types input error");
+ using _RawTp = __remove_cv_t<__libcpp_remove_reference_t<_Tp> >;
+ using _Maker = __make_tuple_types_flat<_RawTp, typename __make_tuple_indices<_Ep, _Sp>::type>;
+ using type = typename _Maker::template __apply_quals<_Tp>;
+};
+
+template <class... _Types, size_t _Ep>
+struct __make_tuple_types<tuple<_Types...>, _Ep, 0, true> {
+ typedef _LIBCPP_NODEBUG __tuple_types<_Types...> type;
+};
+
+template <class... _Types, size_t _Ep>
+struct __make_tuple_types<__tuple_types<_Types...>, _Ep, 0, true> {
+ typedef _LIBCPP_NODEBUG __tuple_types<_Types...> type;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CXX03_LANG
+
+#endif // _LIBCPP___TUPLE_MAKE_TUPLE_TYPES_H
diff --git a/libcxx/include/__cxx03/__tuple/sfinae_helpers.h b/libcxx/include/__cxx03/__tuple/sfinae_helpers.h
new file mode 100644
index 00000000000000..c7145e0b011a99
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/sfinae_helpers.h
@@ -0,0 +1,142 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_SFINAE_HELPERS_H
+#define _LIBCPP___TUPLE_SFINAE_HELPERS_H
+
+#include <__config>
+#include <__fwd/tuple.h>
+#include <__tuple/make_tuple_types.h>
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_like_ext.h>
+#include <__tuple/tuple_size.h>
+#include <__tuple/tuple_types.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_CXX03_LANG
+
+struct __tuple_sfinae_base {
+ template <template <class, class...> class _Trait, class... _LArgs, class... _RArgs>
+ static auto __do_test(__tuple_types<_LArgs...>,
+ __tuple_types<_RArgs...>) -> __all<__enable_if_t<_Trait<_LArgs, _RArgs>::value, bool>{true}...>;
+ template <template <class...> class>
+ static auto __do_test(...) -> false_type;
+
+ template <class _FromArgs, class _ToArgs>
+ using __constructible = decltype(__do_test<is_constructible>(_ToArgs{}, _FromArgs{}));
+};
+
+// __tuple_constructible
+
+template <class _Tp,
+ class _Up,
+ bool = __tuple_like_ext<__libcpp_remove_reference_t<_Tp> >::value,
+ bool = __tuple_like_ext<_Up>::value>
+struct __tuple_constructible : public false_type {};
+
+template <class _Tp, class _Up>
+struct __tuple_constructible<_Tp, _Up, true, true>
+ : public __tuple_sfinae_base::__constructible< typename __make_tuple_types<_Tp>::type,
+ typename __make_tuple_types<_Up>::type > {};
+
+template <size_t _Ip, class... _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, tuple<_Tp...> > {
+ typedef _LIBCPP_NODEBUG typename tuple_element<_Ip, __tuple_types<_Tp...> >::type type;
+};
+
+struct _LIBCPP_EXPORTED_FROM_ABI __check_tuple_constructor_fail {
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __enable_explicit_default() { return false; }
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __enable_implicit_default() { return false; }
+ template <class...>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __enable_explicit() {
+ return false;
+ }
+ template <class...>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __enable_implicit() {
+ return false;
+ }
+ template <class...>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __enable_assign() {
+ return false;
+ }
+};
+#endif // !defined(_LIBCPP_CXX03_LANG)
+
+#if _LIBCPP_STD_VER >= 17
+
+template <bool _CanCopy, bool _CanMove>
+struct __sfinae_ctor_base {};
+template <>
+struct __sfinae_ctor_base<false, false> {
+ __sfinae_ctor_base() = default;
+ __sfinae_ctor_base(__sfinae_ctor_base const&) = delete;
+ __sfinae_ctor_base(__sfinae_ctor_base&&) = delete;
+ __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default;
+ __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default;
+};
+template <>
+struct __sfinae_ctor_base<true, false> {
+ __sfinae_ctor_base() = default;
+ __sfinae_ctor_base(__sfinae_ctor_base const&) = default;
+ __sfinae_ctor_base(__sfinae_ctor_base&&) = delete;
+ __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default;
+ __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default;
+};
+template <>
+struct __sfinae_ctor_base<false, true> {
+ __sfinae_ctor_base() = default;
+ __sfinae_ctor_base(__sfinae_ctor_base const&) = delete;
+ __sfinae_ctor_base(__sfinae_ctor_base&&) = default;
+ __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default;
+ __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default;
+};
+
+template <bool _CanCopy, bool _CanMove>
+struct __sfinae_assign_base {};
+template <>
+struct __sfinae_assign_base<false, false> {
+ __sfinae_assign_base() = default;
+ __sfinae_assign_base(__sfinae_assign_base const&) = default;
+ __sfinae_assign_base(__sfinae_assign_base&&) = default;
+ __sfinae_assign_base& operator=(__sfinae_assign_base const&) = delete;
+ __sfinae_assign_base& operator=(__sfinae_assign_base&&) = delete;
+};
+template <>
+struct __sfinae_assign_base<true, false> {
+ __sfinae_assign_base() = default;
+ __sfinae_assign_base(__sfinae_assign_base const&) = default;
+ __sfinae_assign_base(__sfinae_assign_base&&) = default;
+ __sfinae_assign_base& operator=(__sfinae_assign_base const&) = default;
+ __sfinae_assign_base& operator=(__sfinae_assign_base&&) = delete;
+};
+template <>
+struct __sfinae_assign_base<false, true> {
+ __sfinae_assign_base() = default;
+ __sfinae_assign_base(__sfinae_assign_base const&) = default;
+ __sfinae_assign_base(__sfinae_assign_base&&) = default;
+ __sfinae_assign_base& operator=(__sfinae_assign_base const&) = delete;
+ __sfinae_assign_base& operator=(__sfinae_assign_base&&) = default;
+};
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TUPLE_SFINAE_HELPERS_H
diff --git a/libcxx/include/__cxx03/__tuple/tuple_element.h b/libcxx/include/__cxx03/__tuple/tuple_element.h
new file mode 100644
index 00000000000000..9127c47dc8f1a5
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/tuple_element.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_TUPLE_ELEMENT_H
+#define _LIBCPP___TUPLE_TUPLE_ELEMENT_H
+
+#include <__config>
+#include <__tuple/tuple_indices.h>
+#include <__tuple/tuple_types.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t _Ip, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_element;
+
+template <size_t _Ip, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, const _Tp> {
+ typedef _LIBCPP_NODEBUG const typename tuple_element<_Ip, _Tp>::type type;
+};
+
+template <size_t _Ip, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, volatile _Tp> {
+ typedef _LIBCPP_NODEBUG volatile typename tuple_element<_Ip, _Tp>::type type;
+};
+
+template <size_t _Ip, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, const volatile _Tp> {
+ typedef _LIBCPP_NODEBUG const volatile typename tuple_element<_Ip, _Tp>::type type;
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <size_t _Ip, class... _Types>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, __tuple_types<_Types...> > {
+ static_assert(_Ip < sizeof...(_Types), "tuple_element index out of range");
+ typedef _LIBCPP_NODEBUG __type_pack_element<_Ip, _Types...> type;
+};
+
+# if _LIBCPP_STD_VER >= 14
+template <size_t _Ip, class... _Tp>
+using tuple_element_t _LIBCPP_NODEBUG = typename tuple_element<_Ip, _Tp...>::type;
+# endif
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TUPLE_TUPLE_ELEMENT_H
diff --git a/libcxx/include/__cxx03/__tuple/tuple_indices.h b/libcxx/include/__cxx03/__tuple/tuple_indices.h
new file mode 100644
index 00000000000000..501e711255ec10
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/tuple_indices.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_MAKE_TUPLE_INDICES_H
+#define _LIBCPP___TUPLE_MAKE_TUPLE_INDICES_H
+
+#include <__config>
+#include <__utility/integer_sequence.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t...>
+struct __tuple_indices {};
+
+template <size_t _Ep, size_t _Sp = 0>
+struct __make_tuple_indices {
+ static_assert(_Sp <= _Ep, "__make_tuple_indices input error");
+ typedef __make_indices_imp<_Ep, _Sp> type;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CXX03_LANG
+
+#endif // _LIBCPP___TUPLE_MAKE_TUPLE_INDICES_H
diff --git a/libcxx/include/__cxx03/__tuple/tuple_like.h b/libcxx/include/__cxx03/__tuple/tuple_like.h
new file mode 100644
index 00000000000000..c080a3dcf1e258
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/tuple_like.h
@@ -0,0 +1,42 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_TUPLE_LIKE_H
+#define _LIBCPP___TUPLE_TUPLE_LIKE_H
+
+#include <__config>
+#include <__fwd/subrange.h>
+#include <__tuple/tuple_like_no_subrange.h>
+#include <__tuple/tuple_size.h>
+#include <__type_traits/remove_cvref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+inline constexpr bool __is_ranges_subrange_v = false;
+
+template <class _Iter, class _Sent, ranges::subrange_kind _Kind>
+inline constexpr bool __is_ranges_subrange_v<ranges::subrange<_Iter, _Sent, _Kind>> = true;
+
+template <class _Tp>
+concept __tuple_like = __tuple_like_no_subrange<_Tp> || __is_ranges_subrange_v<remove_cvref_t<_Tp>>;
+
+// As of writing this comment every use of `pair-like` in the standard excludes `ranges::subrange`, so
+// you most likely want to use `__pair_like_no_subrange` if you're looking for `pair-like`.
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TUPLE_TUPLE_LIKE_H
diff --git a/libcxx/include/__cxx03/__tuple/tuple_like_ext.h b/libcxx/include/__cxx03/__tuple/tuple_like_ext.h
new file mode 100644
index 00000000000000..0cc21e0b75fd1a
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/tuple_like_ext.h
@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_TUPLE_LIKE_EXT_H
+#define _LIBCPP___TUPLE_TUPLE_LIKE_EXT_H
+
+#include <__config>
+#include <__fwd/array.h>
+#include <__fwd/pair.h>
+#include <__fwd/tuple.h>
+#include <__tuple/tuple_types.h>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __tuple_like_ext : false_type {};
+
+template <class _Tp>
+struct __tuple_like_ext<const _Tp> : public __tuple_like_ext<_Tp> {};
+template <class _Tp>
+struct __tuple_like_ext<volatile _Tp> : public __tuple_like_ext<_Tp> {};
+template <class _Tp>
+struct __tuple_like_ext<const volatile _Tp> : public __tuple_like_ext<_Tp> {};
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class... _Tp>
+struct __tuple_like_ext<tuple<_Tp...> > : true_type {};
+#endif
+
+template <class _T1, class _T2>
+struct __tuple_like_ext<pair<_T1, _T2> > : true_type {};
+
+template <class _Tp, size_t _Size>
+struct __tuple_like_ext<array<_Tp, _Size> > : true_type {};
+
+template <class... _Tp>
+struct __tuple_like_ext<__tuple_types<_Tp...> > : true_type {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TUPLE_TUPLE_LIKE_EXT_H
diff --git a/libcxx/include/__cxx03/__tuple/tuple_like_no_subrange.h b/libcxx/include/__cxx03/__tuple/tuple_like_no_subrange.h
new file mode 100644
index 00000000000000..274b0bf188e1f4
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/tuple_like_no_subrange.h
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_TUPLE_LIKE_NO_SUBRANGE_H
+#define _LIBCPP___TUPLE_TUPLE_LIKE_NO_SUBRANGE_H
+
+#include <__config>
+#include <__fwd/array.h>
+#include <__fwd/complex.h>
+#include <__fwd/pair.h>
+#include <__fwd/tuple.h>
+#include <__tuple/tuple_size.h>
+#include <__type_traits/remove_cvref.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+inline constexpr bool __tuple_like_no_subrange_impl = false;
+
+template <class... _Tp>
+inline constexpr bool __tuple_like_no_subrange_impl<tuple<_Tp...>> = true;
+
+template <class _T1, class _T2>
+inline constexpr bool __tuple_like_no_subrange_impl<pair<_T1, _T2>> = true;
+
+template <class _Tp, size_t _Size>
+inline constexpr bool __tuple_like_no_subrange_impl<array<_Tp, _Size>> = true;
+
+# if _LIBCPP_STD_VER >= 26
+
+template <class _Tp>
+inline constexpr bool __tuple_like_no_subrange_impl<complex<_Tp>> = true;
+
+# endif
+
+template <class _Tp>
+concept __tuple_like_no_subrange = __tuple_like_no_subrange_impl<remove_cvref_t<_Tp>>;
+
+// This is equivalent to the exposition-only type trait `pair-like`, except that it is false for specializations of
+// `ranges::subrange`. This is more useful than the pair-like concept in the standard because every use of `pair-like`
+// excludes `ranges::subrange`.
+template <class _Tp>
+concept __pair_like_no_subrange = __tuple_like_no_subrange<_Tp> && tuple_size<remove_cvref_t<_Tp>>::value == 2;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TUPLE_TUPLE_LIKE_NO_SUBRANGE_H
diff --git a/libcxx/include/__cxx03/__tuple/tuple_size.h b/libcxx/include/__cxx03/__tuple/tuple_size.h
new file mode 100644
index 00000000000000..18a17fd4d58780
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/tuple_size.h
@@ -0,0 +1,75 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_TUPLE_SIZE_H
+#define _LIBCPP___TUPLE_TUPLE_SIZE_H
+
+#include <__config>
+#include <__fwd/tuple.h>
+#include <__tuple/tuple_types.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_volatile.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_size;
+
+#if !defined(_LIBCPP_CXX03_LANG)
+template <class _Tp, class...>
+using __enable_if_tuple_size_imp = _Tp;
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<__enable_if_tuple_size_imp< const _Tp,
+ __enable_if_t<!is_volatile<_Tp>::value>,
+ integral_constant<size_t, sizeof(tuple_size<_Tp>)>>>
+ : public integral_constant<size_t, tuple_size<_Tp>::value> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<__enable_if_tuple_size_imp< volatile _Tp,
+ __enable_if_t<!is_const<_Tp>::value>,
+ integral_constant<size_t, sizeof(tuple_size<_Tp>)>>>
+ : public integral_constant<size_t, tuple_size<_Tp>::value> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS
+tuple_size<__enable_if_tuple_size_imp<const volatile _Tp, integral_constant<size_t, sizeof(tuple_size<_Tp>)>>>
+ : public integral_constant<size_t, tuple_size<_Tp>::value> {};
+
+#else
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<const _Tp> : public tuple_size<_Tp> {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<volatile _Tp> : public tuple_size<_Tp> {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<const volatile _Tp> : public tuple_size<_Tp> {};
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class... _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<tuple<_Tp...> > : public integral_constant<size_t, sizeof...(_Tp)> {};
+
+template <class... _Tp>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<__tuple_types<_Tp...> > : public integral_constant<size_t, sizeof...(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr size_t tuple_size_v = tuple_size<_Tp>::value;
+# endif
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TUPLE_TUPLE_SIZE_H
diff --git a/libcxx/include/__cxx03/__tuple/tuple_types.h b/libcxx/include/__cxx03/__tuple/tuple_types.h
new file mode 100644
index 00000000000000..7e1256cf8790e1
--- /dev/null
+++ b/libcxx/include/__cxx03/__tuple/tuple_types.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TUPLE_TUPLE_TYPES_H
+#define _LIBCPP___TUPLE_TUPLE_TYPES_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class... _Tp>
+struct __tuple_types {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TUPLE_TUPLE_TYPES_H
diff --git a/libcxx/include/__cxx03/__type_traits/add_const.h b/libcxx/include/__cxx03/__type_traits/add_const.h
new file mode 100644
index 00000000000000..9a6f1c10299f7f
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/add_const.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ADD_CONST_H
+#define _LIBCPP___TYPE_TRAITS_ADD_CONST_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS add_const {
+ typedef _LIBCPP_NODEBUG const _Tp type;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using add_const_t = typename add_const<_Tp>::type;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ADD_CONST_H
diff --git a/libcxx/include/__cxx03/__type_traits/add_cv.h b/libcxx/include/__cxx03/__type_traits/add_cv.h
new file mode 100644
index 00000000000000..9e23e5ceb7a3bd
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/add_cv.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ADD_CV_H
+#define _LIBCPP___TYPE_TRAITS_ADD_CV_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS add_cv {
+ typedef _LIBCPP_NODEBUG const volatile _Tp type;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using add_cv_t = typename add_cv<_Tp>::type;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ADD_CV_H
diff --git a/libcxx/include/__cxx03/__type_traits/add_lvalue_reference.h b/libcxx/include/__cxx03/__type_traits/add_lvalue_reference.h
new file mode 100644
index 00000000000000..a633e390453205
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/add_lvalue_reference.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
+#define _LIBCPP___TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
+
+#include <__config>
+#include <__type_traits/is_referenceable.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__add_lvalue_reference)
+
+template <class _Tp>
+using __add_lvalue_reference_t = __add_lvalue_reference(_Tp);
+
+#else
+
+template <class _Tp, bool = __libcpp_is_referenceable<_Tp>::value>
+struct __add_lvalue_reference_impl {
+ typedef _LIBCPP_NODEBUG _Tp type;
+};
+template <class _Tp >
+struct __add_lvalue_reference_impl<_Tp, true> {
+ typedef _LIBCPP_NODEBUG _Tp& type;
+};
+
+template <class _Tp>
+using __add_lvalue_reference_t = typename __add_lvalue_reference_impl<_Tp>::type;
+
+#endif // __has_builtin(__add_lvalue_reference)
+
+template <class _Tp>
+struct add_lvalue_reference {
+ using type _LIBCPP_NODEBUG = __add_lvalue_reference_t<_Tp>;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using add_lvalue_reference_t = __add_lvalue_reference_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
diff --git a/libcxx/include/__cxx03/__type_traits/add_pointer.h b/libcxx/include/__cxx03/__type_traits/add_pointer.h
new file mode 100644
index 00000000000000..5aac7d5cfa90d8
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/add_pointer.h
@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ADD_POINTER_H
+#define _LIBCPP___TYPE_TRAITS_ADD_POINTER_H
+
+#include <__config>
+#include <__type_traits/is_referenceable.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if !defined(_LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS) && __has_builtin(__add_pointer)
+
+template <class _Tp>
+using __add_pointer_t = __add_pointer(_Tp);
+
+#else
+template <class _Tp, bool = __libcpp_is_referenceable<_Tp>::value || is_void<_Tp>::value>
+struct __add_pointer_impl {
+ typedef _LIBCPP_NODEBUG __libcpp_remove_reference_t<_Tp>* type;
+};
+template <class _Tp>
+struct __add_pointer_impl<_Tp, false> {
+ typedef _LIBCPP_NODEBUG _Tp type;
+};
+
+template <class _Tp>
+using __add_pointer_t = typename __add_pointer_impl<_Tp>::type;
+
+#endif // !defined(_LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS) && __has_builtin(__add_pointer)
+
+template <class _Tp>
+struct add_pointer {
+ using type _LIBCPP_NODEBUG = __add_pointer_t<_Tp>;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using add_pointer_t = __add_pointer_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ADD_POINTER_H
diff --git a/libcxx/include/__cxx03/__type_traits/add_rvalue_reference.h b/libcxx/include/__cxx03/__type_traits/add_rvalue_reference.h
new file mode 100644
index 00000000000000..a54aae7ec8de5d
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/add_rvalue_reference.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
+#define _LIBCPP___TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
+
+#include <__config>
+#include <__type_traits/is_referenceable.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__add_rvalue_reference)
+
+template <class _Tp>
+using __add_rvalue_reference_t = __add_rvalue_reference(_Tp);
+
+#else
+
+template <class _Tp, bool = __libcpp_is_referenceable<_Tp>::value>
+struct __add_rvalue_reference_impl {
+ typedef _LIBCPP_NODEBUG _Tp type;
+};
+template <class _Tp >
+struct __add_rvalue_reference_impl<_Tp, true> {
+ typedef _LIBCPP_NODEBUG _Tp&& type;
+};
+
+template <class _Tp>
+using __add_rvalue_reference_t = typename __add_rvalue_reference_impl<_Tp>::type;
+
+#endif // __has_builtin(__add_rvalue_reference)
+
+template <class _Tp>
+struct add_rvalue_reference {
+ using type = __add_rvalue_reference_t<_Tp>;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using add_rvalue_reference_t = __add_rvalue_reference_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
diff --git a/libcxx/include/__cxx03/__type_traits/add_volatile.h b/libcxx/include/__cxx03/__type_traits/add_volatile.h
new file mode 100644
index 00000000000000..56b7dfaac026e7
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/add_volatile.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ADD_VOLATILE_H
+#define _LIBCPP___TYPE_TRAITS_ADD_VOLATILE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS add_volatile {
+ typedef _LIBCPP_NODEBUG volatile _Tp type;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using add_volatile_t = typename add_volatile<_Tp>::type;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ADD_VOLATILE_H
diff --git a/libcxx/include/__cxx03/__type_traits/aligned_storage.h b/libcxx/include/__cxx03/__type_traits/aligned_storage.h
new file mode 100644
index 00000000000000..46aae12832f867
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/aligned_storage.h
@@ -0,0 +1,138 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ALIGNED_STORAGE_H
+#define _LIBCPP___TYPE_TRAITS_ALIGNED_STORAGE_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/nat.h>
+#include <__type_traits/type_list.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __align_type {
+ static const size_t value = _LIBCPP_PREFERRED_ALIGNOF(_Tp);
+ typedef _Tp type;
+};
+
+struct __struct_double {
+ long double __lx;
+};
+struct __struct_double4 {
+ double __lx[4];
+};
+
+// clang-format off
+typedef __type_list<__align_type<unsigned char>,
+ __type_list<__align_type<unsigned short>,
+ __type_list<__align_type<unsigned int>,
+ __type_list<__align_type<unsigned long>,
+ __type_list<__align_type<unsigned long long>,
+ __type_list<__align_type<double>,
+ __type_list<__align_type<long double>,
+ __type_list<__align_type<__struct_double>,
+ __type_list<__align_type<__struct_double4>,
+ __type_list<__align_type<int*>,
+ __nat
+ > > > > > > > > > > __all_types;
+// clang-format on
+
+template <size_t _Align>
+struct _ALIGNAS(_Align) __fallback_overaligned {};
+
+template <class _TL, size_t _Align>
+struct __find_pod;
+
+template <class _Hp, size_t _Align>
+struct __find_pod<__type_list<_Hp, __nat>, _Align> {
+ typedef __conditional_t<_Align == _Hp::value, typename _Hp::type, __fallback_overaligned<_Align> > type;
+};
+
+template <class _Hp, class _Tp, size_t _Align>
+struct __find_pod<__type_list<_Hp, _Tp>, _Align> {
+ typedef __conditional_t<_Align == _Hp::value, typename _Hp::type, typename __find_pod<_Tp, _Align>::type> type;
+};
+
+template <class _TL, size_t _Len>
+struct __find_max_align;
+
+template <class _Hp, size_t _Len>
+struct __find_max_align<__type_list<_Hp, __nat>, _Len> : public integral_constant<size_t, _Hp::value> {};
+
+template <size_t _Len, size_t _A1, size_t _A2>
+struct __select_align {
+private:
+ static const size_t __min = _A2 < _A1 ? _A2 : _A1;
+ static const size_t __max = _A1 < _A2 ? _A2 : _A1;
+
+public:
+ static const size_t value = _Len < __max ? __min : __max;
+};
+
+template <class _Hp, class _Tp, size_t _Len>
+struct __find_max_align<__type_list<_Hp, _Tp>, _Len>
+ : public integral_constant<size_t, __select_align<_Len, _Hp::value, __find_max_align<_Tp, _Len>::value>::value> {};
+
+template <size_t _Len, size_t _Align = __find_max_align<__all_types, _Len>::value>
+struct _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_TEMPLATE_VIS aligned_storage {
+ typedef typename __find_pod<__all_types, _Align>::type _Aligner;
+ union type {
+ _Aligner __align;
+ unsigned char __data[(_Len + _Align - 1) / _Align * _Align];
+ };
+};
+
+#if _LIBCPP_STD_VER >= 14
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <size_t _Len, size_t _Align = __find_max_align<__all_types, _Len>::value>
+using aligned_storage_t _LIBCPP_DEPRECATED_IN_CXX23 = typename aligned_storage<_Len, _Align>::type;
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+#endif
+
+#define _CREATE_ALIGNED_STORAGE_SPECIALIZATION(n) \
+ template <size_t _Len> \
+ struct _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_TEMPLATE_VIS aligned_storage<_Len, n> { \
+ struct _ALIGNAS(n) type { \
+ unsigned char __lx[(_Len + n - 1) / n * n]; \
+ }; \
+ }
+
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x1);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x2);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x4);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x8);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x10);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x20);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x40);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x80);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x100);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x200);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x400);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x800);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x1000);
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x2000);
+// PE/COFF does not support alignment beyond 8192 (=0x2000)
+#if !defined(_LIBCPP_OBJECT_FORMAT_COFF)
+_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x4000);
+#endif // !defined(_LIBCPP_OBJECT_FORMAT_COFF)
+
+#undef _CREATE_ALIGNED_STORAGE_SPECIALIZATION
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ALIGNED_STORAGE_H
diff --git a/libcxx/include/__cxx03/__type_traits/aligned_union.h b/libcxx/include/__cxx03/__type_traits/aligned_union.h
new file mode 100644
index 00000000000000..005ed9a096ea8e
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/aligned_union.h
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ALIGNED_UNION_H
+#define _LIBCPP___TYPE_TRAITS_ALIGNED_UNION_H
+
+#include <__config>
+#include <__type_traits/aligned_storage.h>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t _I0, size_t... _In>
+struct __static_max;
+
+template <size_t _I0>
+struct __static_max<_I0> {
+ static const size_t value = _I0;
+};
+
+template <size_t _I0, size_t _I1, size_t... _In>
+struct __static_max<_I0, _I1, _In...> {
+ static const size_t value = _I0 >= _I1 ? __static_max<_I0, _In...>::value : __static_max<_I1, _In...>::value;
+};
+
+template <size_t _Len, class _Type0, class... _Types>
+struct _LIBCPP_DEPRECATED_IN_CXX23 aligned_union {
+ static const size_t alignment_value =
+ __static_max<_LIBCPP_PREFERRED_ALIGNOF(_Type0), _LIBCPP_PREFERRED_ALIGNOF(_Types)...>::value;
+ static const size_t __len = __static_max<_Len, sizeof(_Type0), sizeof(_Types)...>::value;
+ typedef typename aligned_storage<__len, alignment_value>::type type;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <size_t _Len, class... _Types>
+using aligned_union_t _LIBCPP_DEPRECATED_IN_CXX23 = typename aligned_union<_Len, _Types...>::type;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ALIGNED_UNION_H
diff --git a/libcxx/include/__cxx03/__type_traits/alignment_of.h b/libcxx/include/__cxx03/__type_traits/alignment_of.h
new file mode 100644
index 00000000000000..f2d069bf2488f7
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/alignment_of.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ALIGNMENT_OF_H
+#define _LIBCPP___TYPE_TRAITS_ALIGNMENT_OF_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS alignment_of : public integral_constant<size_t, _LIBCPP_ALIGNOF(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr size_t alignment_of_v = _LIBCPP_ALIGNOF(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ALIGNMENT_OF_H
diff --git a/libcxx/include/__cxx03/__type_traits/can_extract_key.h b/libcxx/include/__cxx03/__type_traits/can_extract_key.h
new file mode 100644
index 00000000000000..b8359d07088104
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/can_extract_key.h
@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_CAN_EXTRACT_KEY_H
+#define _LIBCPP___TYPE_TRAITS_CAN_EXTRACT_KEY_H
+
+#include <__config>
+#include <__fwd/pair.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_const_ref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// These traits are used in __tree and __hash_table
+struct __extract_key_fail_tag {};
+struct __extract_key_self_tag {};
+struct __extract_key_first_tag {};
+
+template <class _ValTy, class _Key, class _RawValTy = __remove_const_ref_t<_ValTy> >
+struct __can_extract_key
+ : __conditional_t<_IsSame<_RawValTy, _Key>::value, __extract_key_self_tag, __extract_key_fail_tag> {};
+
+template <class _Pair, class _Key, class _First, class _Second>
+struct __can_extract_key<_Pair, _Key, pair<_First, _Second> >
+ : __conditional_t<_IsSame<__remove_const_t<_First>, _Key>::value, __extract_key_first_tag, __extract_key_fail_tag> {
+};
+
+// __can_extract_map_key uses true_type/false_type instead of the tags.
+// It returns true if _Key != _ContainerValueTy (the container is a map not a set)
+// and _ValTy == _Key.
+template <class _ValTy, class _Key, class _ContainerValueTy, class _RawValTy = __remove_const_ref_t<_ValTy> >
+struct __can_extract_map_key : integral_constant<bool, _IsSame<_RawValTy, _Key>::value> {};
+
+// This specialization returns __extract_key_fail_tag for non-map containers
+// because _Key == _ContainerValueTy
+template <class _ValTy, class _Key, class _RawValTy>
+struct __can_extract_map_key<_ValTy, _Key, _Key, _RawValTy> : false_type {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_CAN_EXTRACT_KEY_H
diff --git a/libcxx/include/__cxx03/__type_traits/common_reference.h b/libcxx/include/__cxx03/__type_traits/common_reference.h
new file mode 100644
index 00000000000000..c802902eb19fc3
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/common_reference.h
@@ -0,0 +1,193 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_COMMON_REFERENCE_H
+#define _LIBCPP___TYPE_TRAITS_COMMON_REFERENCE_H
+
+#include <__config>
+#include <__type_traits/common_type.h>
+#include <__type_traits/copy_cv.h>
+#include <__type_traits/copy_cvref.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// common_reference
+#if _LIBCPP_STD_VER >= 20
+// Let COND_RES(X, Y) be:
+template <class _Xp, class _Yp>
+using __cond_res = decltype(false ? std::declval<_Xp (&)()>()() : std::declval<_Yp (&)()>()());
+
+// Let `XREF(A)` denote a unary alias template `T` such that `T<U>` denotes the same type as `U`
+// with the addition of `A`'s cv and reference qualifiers, for a non-reference cv-unqualified type
+// `U`.
+// [Note: `XREF(A)` is `__xref<A>::template __apply`]
+template <class _Tp>
+struct __xref {
+ template <class _Up>
+ using __apply = __copy_cvref_t<_Tp, _Up>;
+};
+
+// Given types A and B, let X be remove_reference_t<A>, let Y be remove_reference_t<B>,
+// and let COMMON-REF(A, B) be:
+template <class _Ap, class _Bp, class _Xp = remove_reference_t<_Ap>, class _Yp = remove_reference_t<_Bp>>
+struct __common_ref;
+
+template <class _Xp, class _Yp>
+using __common_ref_t = typename __common_ref<_Xp, _Yp>::__type;
+
+template <class _Xp, class _Yp>
+using __cv_cond_res = __cond_res<__copy_cv_t<_Xp, _Yp>&, __copy_cv_t<_Yp, _Xp>&>;
+
+// If A and B are both lvalue reference types, COMMON-REF(A, B) is
+// COND-RES(COPYCV(X, Y)&, COPYCV(Y, X)&) if that type exists and is a reference type.
+// clang-format off
+template <class _Ap, class _Bp, class _Xp, class _Yp>
+ requires
+ requires { typename __cv_cond_res<_Xp, _Yp>; } &&
+ is_reference_v<__cv_cond_res<_Xp, _Yp>>
+struct __common_ref<_Ap&, _Bp&, _Xp, _Yp> {
+ using __type = __cv_cond_res<_Xp, _Yp>;
+};
+// clang-format on
+
+// Otherwise, let C be remove_reference_t<COMMON-REF(X&, Y&)>&&. ...
+template <class _Xp, class _Yp>
+using __common_ref_C = remove_reference_t<__common_ref_t<_Xp&, _Yp&>>&&;
+
+// .... If A and B are both rvalue reference types, C is well-formed, and
+// is_convertible_v<A, C> && is_convertible_v<B, C> is true, then COMMON-REF(A, B) is C.
+// clang-format off
+template <class _Ap, class _Bp, class _Xp, class _Yp>
+ requires
+ requires { typename __common_ref_C<_Xp, _Yp>; } &&
+ is_convertible_v<_Ap&&, __common_ref_C<_Xp, _Yp>> &&
+ is_convertible_v<_Bp&&, __common_ref_C<_Xp, _Yp>>
+struct __common_ref<_Ap&&, _Bp&&, _Xp, _Yp> {
+ using __type = __common_ref_C<_Xp, _Yp>;
+};
+// clang-format on
+
+// Otherwise, let D be COMMON-REF(const X&, Y&). ...
+template <class _Tp, class _Up>
+using __common_ref_D = __common_ref_t<const _Tp&, _Up&>;
+
+// ... If A is an rvalue reference and B is an lvalue reference and D is well-formed and
+// is_convertible_v<A, D> is true, then COMMON-REF(A, B) is D.
+// clang-format off
+template <class _Ap, class _Bp, class _Xp, class _Yp>
+ requires
+ requires { typename __common_ref_D<_Xp, _Yp>; } &&
+ is_convertible_v<_Ap&&, __common_ref_D<_Xp, _Yp>>
+struct __common_ref<_Ap&&, _Bp&, _Xp, _Yp> {
+ using __type = __common_ref_D<_Xp, _Yp>;
+};
+// clang-format on
+
+// Otherwise, if A is an lvalue reference and B is an rvalue reference, then
+// COMMON-REF(A, B) is COMMON-REF(B, A).
+template <class _Ap, class _Bp, class _Xp, class _Yp>
+struct __common_ref<_Ap&, _Bp&&, _Xp, _Yp> : __common_ref<_Bp&&, _Ap&> {};
+
+// Otherwise, COMMON-REF(A, B) is ill-formed.
+template <class _Ap, class _Bp, class _Xp, class _Yp>
+struct __common_ref {};
+
+// Note C: For the common_reference trait applied to a parameter pack [...]
+
+template <class...>
+struct common_reference;
+
+template <class... _Types>
+using common_reference_t = typename common_reference<_Types...>::type;
+
+// bullet 1 - sizeof...(T) == 0
+template <>
+struct common_reference<> {};
+
+// bullet 2 - sizeof...(T) == 1
+template <class _Tp>
+struct common_reference<_Tp> {
+ using type = _Tp;
+};
+
+// bullet 3 - sizeof...(T) == 2
+template <class _Tp, class _Up>
+struct __common_reference_sub_bullet3;
+template <class _Tp, class _Up>
+struct __common_reference_sub_bullet2 : __common_reference_sub_bullet3<_Tp, _Up> {};
+template <class _Tp, class _Up>
+struct __common_reference_sub_bullet1 : __common_reference_sub_bullet2<_Tp, _Up> {};
+
+// sub-bullet 1 - If T1 and T2 are reference types and COMMON-REF(T1, T2) is well-formed, then
+// the member typedef `type` denotes that type.
+template <class _Tp, class _Up>
+struct common_reference<_Tp, _Up> : __common_reference_sub_bullet1<_Tp, _Up> {};
+
+template <class _Tp, class _Up>
+ requires is_reference_v<_Tp> && is_reference_v<_Up> && requires { typename __common_ref_t<_Tp, _Up>; }
+struct __common_reference_sub_bullet1<_Tp, _Up> {
+ using type = __common_ref_t<_Tp, _Up>;
+};
+
+// sub-bullet 2 - Otherwise, if basic_common_reference<remove_cvref_t<T1>, remove_cvref_t<T2>, XREF(T1), XREF(T2)>::type
+// is well-formed, then the member typedef `type` denotes that type.
+template <class, class, template <class> class, template <class> class>
+struct basic_common_reference {};
+
+template <class _Tp, class _Up>
+using __basic_common_reference_t =
+ typename basic_common_reference<remove_cvref_t<_Tp>,
+ remove_cvref_t<_Up>,
+ __xref<_Tp>::template __apply,
+ __xref<_Up>::template __apply>::type;
+
+template <class _Tp, class _Up>
+ requires requires { typename __basic_common_reference_t<_Tp, _Up>; }
+struct __common_reference_sub_bullet2<_Tp, _Up> {
+ using type = __basic_common_reference_t<_Tp, _Up>;
+};
+
+// sub-bullet 3 - Otherwise, if COND-RES(T1, T2) is well-formed,
+// then the member typedef `type` denotes that type.
+template <class _Tp, class _Up>
+ requires requires { typename __cond_res<_Tp, _Up>; }
+struct __common_reference_sub_bullet3<_Tp, _Up> {
+ using type = __cond_res<_Tp, _Up>;
+};
+
+// sub-bullet 4 & 5 - Otherwise, if common_type_t<T1, T2> is well-formed,
+// then the member typedef `type` denotes that type.
+// - Otherwise, there shall be no member `type`.
+template <class _Tp, class _Up>
+struct __common_reference_sub_bullet3 : common_type<_Tp, _Up> {};
+
+// bullet 4 - If there is such a type `C`, the member typedef type shall denote the same type, if
+// any, as `common_reference_t<C, Rest...>`.
+template <class _Tp, class _Up, class _Vp, class... _Rest>
+ requires requires { typename common_reference_t<_Tp, _Up>; }
+struct common_reference<_Tp, _Up, _Vp, _Rest...> : common_reference<common_reference_t<_Tp, _Up>, _Vp, _Rest...> {};
+
+// bullet 5 - Otherwise, there shall be no member `type`.
+template <class...>
+struct common_reference {};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_COMMON_REFERENCE_H
diff --git a/libcxx/include/__cxx03/__type_traits/common_type.h b/libcxx/include/__cxx03/__type_traits/common_type.h
new file mode 100644
index 00000000000000..f6bd9ed71b7a47
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/common_type.h
@@ -0,0 +1,102 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_COMMON_TYPE_H
+#define _LIBCPP___TYPE_TRAITS_COMMON_TYPE_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+// Let COND_RES(X, Y) be:
+template <class _Tp, class _Up>
+using __cond_type = decltype(false ? std::declval<_Tp>() : std::declval<_Up>());
+
+template <class _Tp, class _Up, class = void>
+struct __common_type3 {};
+
+// sub-bullet 4 - "if COND_RES(CREF(D1), CREF(D2)) denotes a type..."
+template <class _Tp, class _Up>
+struct __common_type3<_Tp, _Up, void_t<__cond_type<const _Tp&, const _Up&>>> {
+ using type = remove_cvref_t<__cond_type<const _Tp&, const _Up&>>;
+};
+
+template <class _Tp, class _Up, class = void>
+struct __common_type2_imp : __common_type3<_Tp, _Up> {};
+#else
+template <class _Tp, class _Up, class = void>
+struct __common_type2_imp {};
+#endif
+
+// sub-bullet 3 - "if decay_t<decltype(false ? declval<D1>() : declval<D2>())> ..."
+template <class _Tp, class _Up>
+struct __common_type2_imp<_Tp, _Up, __void_t<decltype(true ? std::declval<_Tp>() : std::declval<_Up>())> > {
+ typedef _LIBCPP_NODEBUG __decay_t<decltype(true ? std::declval<_Tp>() : std::declval<_Up>())> type;
+};
+
+template <class, class = void>
+struct __common_type_impl {};
+
+template <class... _Tp>
+struct __common_types;
+template <class... _Tp>
+struct _LIBCPP_TEMPLATE_VIS common_type;
+
+template <class _Tp, class _Up>
+struct __common_type_impl< __common_types<_Tp, _Up>, __void_t<typename common_type<_Tp, _Up>::type> > {
+ typedef typename common_type<_Tp, _Up>::type type;
+};
+
+template <class _Tp, class _Up, class _Vp, class... _Rest>
+struct __common_type_impl<__common_types<_Tp, _Up, _Vp, _Rest...>, __void_t<typename common_type<_Tp, _Up>::type> >
+ : __common_type_impl<__common_types<typename common_type<_Tp, _Up>::type, _Vp, _Rest...> > {};
+
+// bullet 1 - sizeof...(Tp) == 0
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS common_type<> {};
+
+// bullet 2 - sizeof...(Tp) == 1
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS common_type<_Tp> : public common_type<_Tp, _Tp> {};
+
+// bullet 3 - sizeof...(Tp) == 2
+
+// sub-bullet 1 - "If is_same_v<T1, D1> is false or ..."
+template <class _Tp, class _Up>
+struct _LIBCPP_TEMPLATE_VIS common_type<_Tp, _Up>
+ : __conditional_t<_IsSame<_Tp, __decay_t<_Tp> >::value && _IsSame<_Up, __decay_t<_Up> >::value,
+ __common_type2_imp<_Tp, _Up>,
+ common_type<__decay_t<_Tp>, __decay_t<_Up> > > {};
+
+// bullet 4 - sizeof...(Tp) > 2
+
+template <class _Tp, class _Up, class _Vp, class... _Rest>
+struct _LIBCPP_TEMPLATE_VIS common_type<_Tp, _Up, _Vp, _Rest...>
+ : __common_type_impl<__common_types<_Tp, _Up, _Vp, _Rest...> > {};
+
+#if _LIBCPP_STD_VER >= 14
+template <class... _Tp>
+using common_type_t = typename common_type<_Tp...>::type;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_COMMON_TYPE_H
diff --git a/libcxx/include/__cxx03/__type_traits/conditional.h b/libcxx/include/__cxx03/__type_traits/conditional.h
new file mode 100644
index 00000000000000..5b5445a8374271
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/conditional.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_CONDITIONAL_H
+#define _LIBCPP___TYPE_TRAITS_CONDITIONAL_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <bool>
+struct _IfImpl;
+
+template <>
+struct _IfImpl<true> {
+ template <class _IfRes, class _ElseRes>
+ using _Select _LIBCPP_NODEBUG = _IfRes;
+};
+
+template <>
+struct _IfImpl<false> {
+ template <class _IfRes, class _ElseRes>
+ using _Select _LIBCPP_NODEBUG = _ElseRes;
+};
+
+template <bool _Cond, class _IfRes, class _ElseRes>
+using _If _LIBCPP_NODEBUG = typename _IfImpl<_Cond>::template _Select<_IfRes, _ElseRes>;
+
+template <bool _Bp, class _If, class _Then>
+struct _LIBCPP_TEMPLATE_VIS conditional {
+ using type _LIBCPP_NODEBUG = _If;
+};
+template <class _If, class _Then>
+struct _LIBCPP_TEMPLATE_VIS conditional<false, _If, _Then> {
+ using type _LIBCPP_NODEBUG = _Then;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <bool _Bp, class _IfRes, class _ElseRes>
+using conditional_t _LIBCPP_NODEBUG = typename conditional<_Bp, _IfRes, _ElseRes>::type;
+#endif
+
+// Helper so we can use "conditional_t" in all language versions.
+template <bool _Bp, class _If, class _Then>
+using __conditional_t _LIBCPP_NODEBUG = typename conditional<_Bp, _If, _Then>::type;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_CONDITIONAL_H
diff --git a/libcxx/include/__cxx03/__type_traits/conjunction.h b/libcxx/include/__cxx03/__type_traits/conjunction.h
new file mode 100644
index 00000000000000..c2995591bbc28f
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/conjunction.h
@@ -0,0 +1,65 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_CONJUNCTION_H
+#define _LIBCPP___TYPE_TRAITS_CONJUNCTION_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class...>
+using __expand_to_true = true_type;
+
+template <class... _Pred>
+__expand_to_true<__enable_if_t<_Pred::value>...> __and_helper(int);
+
+template <class...>
+false_type __and_helper(...);
+
+// _And always performs lazy evaluation of its arguments.
+//
+// However, `_And<_Pred...>` itself will evaluate its result immediately (without having to
+// be instantiated) since it is an alias, unlike `conjunction<_Pred...>`, which is a struct.
+// If you want to defer the evaluation of `_And<_Pred...>` itself, use `_Lazy<_And, _Pred...>`.
+template <class... _Pred>
+using _And _LIBCPP_NODEBUG = decltype(std::__and_helper<_Pred...>(0));
+
+template <bool... _Preds>
+struct __all_dummy;
+
+template <bool... _Pred>
+struct __all : _IsSame<__all_dummy<_Pred...>, __all_dummy<((void)_Pred, true)...> > {};
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class...>
+struct conjunction : true_type {};
+
+template <class _Arg>
+struct conjunction<_Arg> : _Arg {};
+
+template <class _Arg, class... _Args>
+struct conjunction<_Arg, _Args...> : conditional_t<!bool(_Arg::value), _Arg, conjunction<_Args...>> {};
+
+template <class... _Args>
+inline constexpr bool conjunction_v = conjunction<_Args...>::value;
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_CONJUNCTION_H
diff --git a/libcxx/include/__cxx03/__type_traits/copy_cv.h b/libcxx/include/__cxx03/__type_traits/copy_cv.h
new file mode 100644
index 00000000000000..d482cb42bffed9
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/copy_cv.h
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_COPY_CV_H
+#define _LIBCPP___TYPE_TRAITS_COPY_CV_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Let COPYCV(FROM, TO) be an alias for type TO with the addition of FROM's
+// top-level cv-qualifiers.
+template <class _From>
+struct __copy_cv {
+ template <class _To>
+ using __apply = _To;
+};
+
+template <class _From>
+struct __copy_cv<const _From> {
+ template <class _To>
+ using __apply = const _To;
+};
+
+template <class _From>
+struct __copy_cv<volatile _From> {
+ template <class _To>
+ using __apply = volatile _To;
+};
+
+template <class _From>
+struct __copy_cv<const volatile _From> {
+ template <class _To>
+ using __apply = const volatile _To;
+};
+
+template <class _From, class _To>
+using __copy_cv_t = typename __copy_cv<_From>::template __apply<_To>;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_COPY_CV_H
diff --git a/libcxx/include/__cxx03/__type_traits/copy_cvref.h b/libcxx/include/__cxx03/__type_traits/copy_cvref.h
new file mode 100644
index 00000000000000..8bbf8efdf44dea
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/copy_cvref.h
@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_COPY_CVREF_H
+#define _LIBCPP___TYPE_TRAITS_COPY_CVREF_H
+
+#include <__config>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_rvalue_reference.h>
+#include <__type_traits/copy_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _From, class _To>
+struct __copy_cvref {
+ using type = __copy_cv_t<_From, _To>;
+};
+
+template <class _From, class _To>
+struct __copy_cvref<_From&, _To> {
+ using type = __add_lvalue_reference_t<__copy_cv_t<_From, _To> >;
+};
+
+template <class _From, class _To>
+struct __copy_cvref<_From&&, _To> {
+ using type = __add_rvalue_reference_t<__copy_cv_t<_From, _To> >;
+};
+
+template <class _From, class _To>
+using __copy_cvref_t = typename __copy_cvref<_From, _To>::type;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_COPY_CVREF_H
diff --git a/libcxx/include/__cxx03/__type_traits/datasizeof.h b/libcxx/include/__cxx03/__type_traits/datasizeof.h
new file mode 100644
index 00000000000000..a27baf67cc2d8a
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/datasizeof.h
@@ -0,0 +1,65 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_DATASIZEOF_H
+#define _LIBCPP___TYPE_TRAITS_DATASIZEOF_H
+
+#include <__config>
+#include <__type_traits/is_class.h>
+#include <__type_traits/is_final.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// This trait provides the size of a type excluding any tail padding.
+//
+// It is useful in contexts where performing an operation using the full size of the class (including padding) may
+// have unintended side effects, such as overwriting a derived class' member when writing the tail padding of a class
+// through a pointer-to-base.
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_keyword(__datasizeof) || __has_extension(datasizeof)
+template <class _Tp>
+inline const size_t __datasizeof_v = __datasizeof(_Tp);
+#else
+// NOLINTNEXTLINE(readability-redundant-preprocessor) This is https://llvm.org/PR64825
+# if __has_cpp_attribute(__no_unique_address__)
+template <class _Tp>
+struct _FirstPaddingByte {
+ [[__no_unique_address__]] _Tp __v_;
+ char __first_padding_byte_;
+};
+# else
+template <class _Tp, bool = __libcpp_is_final<_Tp>::value || !is_class<_Tp>::value>
+struct _FirstPaddingByte : _Tp {
+ char __first_padding_byte_;
+};
+
+template <class _Tp>
+struct _FirstPaddingByte<_Tp, true> {
+ _Tp __v_;
+ char __first_padding_byte_;
+};
+# endif // __has_cpp_attribute(__no_unique_address__)
+
+// _FirstPaddingByte<> is sometimes non-standard layout. Using `offsetof` is UB in that case, but GCC and Clang allow
+// the use as an extension.
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Winvalid-offsetof")
+_LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Winvalid-offsetof")
+template <class _Tp>
+inline const size_t __datasizeof_v = offsetof(_FirstPaddingByte<_Tp>, __first_padding_byte_);
+_LIBCPP_DIAGNOSTIC_POP
+#endif // __has_extension(datasizeof)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_DATASIZEOF_H
diff --git a/libcxx/include/__cxx03/__type_traits/decay.h b/libcxx/include/__cxx03/__type_traits/decay.h
new file mode 100644
index 00000000000000..7412044f931796
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/decay.h
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_DECAY_H
+#define _LIBCPP___TYPE_TRAITS_DECAY_H
+
+#include <__config>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_referenceable.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_extent.h>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__decay)
+template <class _Tp>
+using __decay_t _LIBCPP_NODEBUG = __decay(_Tp);
+
+template <class _Tp>
+struct decay {
+ using type _LIBCPP_NODEBUG = __decay_t<_Tp>;
+};
+
+#else
+template <class _Up, bool>
+struct __decay {
+ typedef _LIBCPP_NODEBUG __remove_cv_t<_Up> type;
+};
+
+template <class _Up>
+struct __decay<_Up, true> {
+public:
+ typedef _LIBCPP_NODEBUG
+ __conditional_t<is_array<_Up>::value,
+ __add_pointer_t<__remove_extent_t<_Up> >,
+ __conditional_t<is_function<_Up>::value, typename add_pointer<_Up>::type, __remove_cv_t<_Up> > >
+ type;
+};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS decay {
+private:
+ typedef _LIBCPP_NODEBUG __libcpp_remove_reference_t<_Tp> _Up;
+
+public:
+ typedef _LIBCPP_NODEBUG typename __decay<_Up, __libcpp_is_referenceable<_Up>::value>::type type;
+};
+
+template <class _Tp>
+using __decay_t = typename decay<_Tp>::type;
+#endif // __has_builtin(__decay)
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using decay_t = __decay_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_DECAY_H
diff --git a/libcxx/include/__cxx03/__type_traits/dependent_type.h b/libcxx/include/__cxx03/__type_traits/dependent_type.h
new file mode 100644
index 00000000000000..db8a869820db31
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/dependent_type.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_DEPENDENT_TYPE_H
+#define _LIBCPP___TYPE_TRAITS_DEPENDENT_TYPE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, bool>
+struct _LIBCPP_TEMPLATE_VIS __dependent_type : public _Tp {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_DEPENDENT_TYPE_H
diff --git a/libcxx/include/__cxx03/__type_traits/desugars_to.h b/libcxx/include/__cxx03/__type_traits/desugars_to.h
new file mode 100644
index 00000000000000..97a2ee5448f203
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/desugars_to.h
@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_DESUGARS_TO_H
+#define _LIBCPP___TYPE_TRAITS_DESUGARS_TO_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Tags to represent the canonical operations
+struct __equal_tag {};
+struct __plus_tag {};
+struct __less_tag {};
+
+// This class template is used to determine whether an operation "desugars"
+// (or boils down) to a given canonical operation.
+//
+// For example, `std::equal_to<>`, our internal `std::__equal_to` helper and
+// `ranges::equal_to` are all just fancy ways of representing a transparent
+// equality operation, so they all desugar to `__equal_tag`.
+//
+// This is useful to optimize some functions in cases where we know e.g. the
+// predicate being passed is actually going to call a builtin operator, or has
+// some specific semantics.
+template <class _CanonicalTag, class _Operation, class... _Args>
+inline const bool __desugars_to_v = false;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_DESUGARS_TO_H
diff --git a/libcxx/include/__cxx03/__type_traits/disjunction.h b/libcxx/include/__cxx03/__type_traits/disjunction.h
new file mode 100644
index 00000000000000..2c89528d9f2fc0
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/disjunction.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_DISJUNCTION_H
+#define _LIBCPP___TYPE_TRAITS_DISJUNCTION_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <bool>
+struct _OrImpl;
+
+template <>
+struct _OrImpl<true> {
+ template <class _Res, class _First, class... _Rest>
+ using _Result _LIBCPP_NODEBUG =
+ typename _OrImpl<!bool(_First::value) && sizeof...(_Rest) != 0>::template _Result<_First, _Rest...>;
+};
+
+template <>
+struct _OrImpl<false> {
+ template <class _Res, class...>
+ using _Result = _Res;
+};
+
+// _Or always performs lazy evaluation of its arguments.
+//
+// However, `_Or<_Pred...>` itself will evaluate its result immediately (without having to
+// be instantiated) since it is an alias, unlike `disjunction<_Pred...>`, which is a struct.
+// If you want to defer the evaluation of `_Or<_Pred...>` itself, use `_Lazy<_Or, _Pred...>`
+// or `disjunction<_Pred...>` directly.
+template <class... _Args>
+using _Or _LIBCPP_NODEBUG = typename _OrImpl<sizeof...(_Args) != 0>::template _Result<false_type, _Args...>;
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class... _Args>
+struct disjunction : _Or<_Args...> {};
+
+template <class... _Args>
+inline constexpr bool disjunction_v = _Or<_Args...>::value;
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_DISJUNCTION_H
diff --git a/libcxx/include/__cxx03/__type_traits/enable_if.h b/libcxx/include/__cxx03/__type_traits/enable_if.h
new file mode 100644
index 00000000000000..77da9622ca28fc
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/enable_if.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_ENABLE_IF_H
+#define _LIBCPP___TYPE_TRAITS_ENABLE_IF_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <bool, class _Tp = void>
+struct _LIBCPP_TEMPLATE_VIS enable_if {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS enable_if<true, _Tp> {
+ typedef _Tp type;
+};
+
+template <bool _Bp, class _Tp = void>
+using __enable_if_t _LIBCPP_NODEBUG = typename enable_if<_Bp, _Tp>::type;
+
+#if _LIBCPP_STD_VER >= 14
+template <bool _Bp, class _Tp = void>
+using enable_if_t = typename enable_if<_Bp, _Tp>::type;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ENABLE_IF_H
diff --git a/libcxx/include/__cxx03/__type_traits/extent.h b/libcxx/include/__cxx03/__type_traits/extent.h
new file mode 100644
index 00000000000000..bab03fe997eb6b
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/extent.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_EXTENT_H
+#define _LIBCPP___TYPE_TRAITS_EXTENT_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__array_extent)
+
+template <class _Tp, size_t _Dim = 0>
+struct _LIBCPP_TEMPLATE_VIS extent : integral_constant<size_t, __array_extent(_Tp, _Dim)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp, unsigned _Ip = 0>
+inline constexpr size_t extent_v = __array_extent(_Tp, _Ip);
+# endif
+
+#else // __has_builtin(__array_extent)
+
+template <class _Tp, unsigned _Ip = 0>
+struct _LIBCPP_TEMPLATE_VIS extent : public integral_constant<size_t, 0> {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS extent<_Tp[], 0> : public integral_constant<size_t, 0> {};
+template <class _Tp, unsigned _Ip>
+struct _LIBCPP_TEMPLATE_VIS extent<_Tp[], _Ip> : public integral_constant<size_t, extent<_Tp, _Ip - 1>::value> {};
+template <class _Tp, size_t _Np>
+struct _LIBCPP_TEMPLATE_VIS extent<_Tp[_Np], 0> : public integral_constant<size_t, _Np> {};
+template <class _Tp, size_t _Np, unsigned _Ip>
+struct _LIBCPP_TEMPLATE_VIS extent<_Tp[_Np], _Ip> : public integral_constant<size_t, extent<_Tp, _Ip - 1>::value> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp, unsigned _Ip = 0>
+inline constexpr size_t extent_v = extent<_Tp, _Ip>::value;
+# endif
+
+#endif // __has_builtin(__array_extent)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_EXTENT_H
diff --git a/libcxx/include/__cxx03/__type_traits/has_unique_object_representation.h b/libcxx/include/__cxx03/__type_traits/has_unique_object_representation.h
new file mode 100644
index 00000000000000..98c440c16bf26b
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/has_unique_object_representation.h
@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_HAS_UNIQUE_OBJECT_REPRESENTATION_H
+#define _LIBCPP___TYPE_TRAITS_HAS_UNIQUE_OBJECT_REPRESENTATION_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/remove_all_extents.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS has_unique_object_representations
+ // TODO: We work around a Clang and GCC bug in __has_unique_object_representations by using remove_all_extents
+ // even though it should not be necessary. This was reported to the compilers:
+ // - Clang: https://github.com/llvm/llvm-project/issues/95311
+ // - GCC: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115476
+ // remove_all_extents_t can be removed once all the compilers we support have fixed this bug.
+ : public integral_constant<bool, __has_unique_object_representations(remove_all_extents_t<_Tp>)> {};
+
+template <class _Tp>
+inline constexpr bool has_unique_object_representations_v = __has_unique_object_representations(_Tp);
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_HAS_UNIQUE_OBJECT_REPRESENTATION_H
diff --git a/libcxx/include/__cxx03/__type_traits/has_virtual_destructor.h b/libcxx/include/__cxx03/__type_traits/has_virtual_destructor.h
new file mode 100644
index 00000000000000..4ce96e649e67a1
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/has_virtual_destructor.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_HAS_VIRTUAL_DESTRUCTOR_H
+#define _LIBCPP___TYPE_TRAITS_HAS_VIRTUAL_DESTRUCTOR_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS has_virtual_destructor : public integral_constant<bool, __has_virtual_destructor(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool has_virtual_destructor_v = __has_virtual_destructor(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_HAS_VIRTUAL_DESTRUCTOR_H
diff --git a/libcxx/include/__cxx03/__type_traits/integral_constant.h b/libcxx/include/__cxx03/__type_traits/integral_constant.h
new file mode 100644
index 00000000000000..23e87e27feff55
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/integral_constant.h
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_INTEGRAL_CONSTANT_H
+#define _LIBCPP___TYPE_TRAITS_INTEGRAL_CONSTANT_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, _Tp __v>
+struct _LIBCPP_TEMPLATE_VIS integral_constant {
+ static _LIBCPP_CONSTEXPR const _Tp value = __v;
+ typedef _Tp value_type;
+ typedef integral_constant type;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR operator value_type() const _NOEXCEPT { return value; }
+#if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type operator()() const _NOEXCEPT { return value; }
+#endif
+};
+
+template <class _Tp, _Tp __v>
+_LIBCPP_CONSTEXPR const _Tp integral_constant<_Tp, __v>::value;
+
+typedef integral_constant<bool, true> true_type;
+typedef integral_constant<bool, false> false_type;
+
+template <bool _Val>
+using _BoolConstant _LIBCPP_NODEBUG = integral_constant<bool, _Val>;
+
+#if _LIBCPP_STD_VER >= 17
+template <bool __b>
+using bool_constant = integral_constant<bool, __b>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_INTEGRAL_CONSTANT_H
diff --git a/libcxx/include/__cxx03/__type_traits/invoke.h b/libcxx/include/__cxx03/__type_traits/invoke.h
new file mode 100644
index 00000000000000..71db32ae6a3cef
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/invoke.h
@@ -0,0 +1,270 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_INVOKE_H
+#define _LIBCPP___TYPE_TRAITS_INVOKE_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_base_of.h>
+#include <__type_traits/is_core_convertible.h>
+#include <__type_traits/is_member_pointer.h>
+#include <__type_traits/is_reference_wrapper.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/nat.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _DecayedFp>
+struct __member_pointer_class_type {};
+
+template <class _Ret, class _ClassType>
+struct __member_pointer_class_type<_Ret _ClassType::*> {
+ typedef _ClassType type;
+};
+
+template <class _Fp,
+ class _A0,
+ class _DecayFp = __decay_t<_Fp>,
+ class _DecayA0 = __decay_t<_A0>,
+ class _ClassT = typename __member_pointer_class_type<_DecayFp>::type>
+using __enable_if_bullet1 =
+ __enable_if_t<is_member_function_pointer<_DecayFp>::value &&
+ (is_same<_ClassT, _DecayA0>::value || is_base_of<_ClassT, _DecayA0>::value)>;
+
+template <class _Fp, class _A0, class _DecayFp = __decay_t<_Fp>, class _DecayA0 = __decay_t<_A0> >
+using __enable_if_bullet2 =
+ __enable_if_t<is_member_function_pointer<_DecayFp>::value && __is_reference_wrapper<_DecayA0>::value>;
+
+template <class _Fp,
+ class _A0,
+ class _DecayFp = __decay_t<_Fp>,
+ class _DecayA0 = __decay_t<_A0>,
+ class _ClassT = typename __member_pointer_class_type<_DecayFp>::type>
+using __enable_if_bullet3 =
+ __enable_if_t<is_member_function_pointer<_DecayFp>::value &&
+ !(is_same<_ClassT, _DecayA0>::value || is_base_of<_ClassT, _DecayA0>::value) &&
+ !__is_reference_wrapper<_DecayA0>::value>;
+
+template <class _Fp,
+ class _A0,
+ class _DecayFp = __decay_t<_Fp>,
+ class _DecayA0 = __decay_t<_A0>,
+ class _ClassT = typename __member_pointer_class_type<_DecayFp>::type>
+using __enable_if_bullet4 =
+ __enable_if_t<is_member_object_pointer<_DecayFp>::value &&
+ (is_same<_ClassT, _DecayA0>::value || is_base_of<_ClassT, _DecayA0>::value)>;
+
+template <class _Fp, class _A0, class _DecayFp = __decay_t<_Fp>, class _DecayA0 = __decay_t<_A0> >
+using __enable_if_bullet5 =
+ __enable_if_t<is_member_object_pointer<_DecayFp>::value && __is_reference_wrapper<_DecayA0>::value>;
+
+template <class _Fp,
+ class _A0,
+ class _DecayFp = __decay_t<_Fp>,
+ class _DecayA0 = __decay_t<_A0>,
+ class _ClassT = typename __member_pointer_class_type<_DecayFp>::type>
+using __enable_if_bullet6 =
+ __enable_if_t<is_member_object_pointer<_DecayFp>::value &&
+ !(is_same<_ClassT, _DecayA0>::value || is_base_of<_ClassT, _DecayA0>::value) &&
+ !__is_reference_wrapper<_DecayA0>::value>;
+
+// __invoke forward declarations
+
+// fall back - none of the bullets
+
+template <class... _Args>
+__nat __invoke(_Args&&... __args);
+
+// bullets 1, 2 and 3
+
+// clang-format off
+template <class _Fp, class _A0, class... _Args, class = __enable_if_bullet1<_Fp, _A0> >
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+decltype((std::declval<_A0>().*std::declval<_Fp>())(std::declval<_Args>()...))
+__invoke(_Fp&& __f, _A0&& __a0, _Args&&... __args)
+ _NOEXCEPT_(noexcept((static_cast<_A0&&>(__a0).*__f)(static_cast<_Args&&>(__args)...)))
+ { return (static_cast<_A0&&>(__a0).*__f)(static_cast<_Args&&>(__args)...); }
+
+template <class _Fp, class _A0, class... _Args, class = __enable_if_bullet2<_Fp, _A0> >
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+decltype((std::declval<_A0>().get().*std::declval<_Fp>())(std::declval<_Args>()...))
+__invoke(_Fp&& __f, _A0&& __a0, _Args&&... __args)
+ _NOEXCEPT_(noexcept((__a0.get().*__f)(static_cast<_Args&&>(__args)...)))
+ { return (__a0.get().*__f)(static_cast<_Args&&>(__args)...); }
+
+template <class _Fp, class _A0, class... _Args, class = __enable_if_bullet3<_Fp, _A0> >
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+decltype(((*std::declval<_A0>()).*std::declval<_Fp>())(std::declval<_Args>()...))
+__invoke(_Fp&& __f, _A0&& __a0, _Args&&... __args)
+ _NOEXCEPT_(noexcept(((*static_cast<_A0&&>(__a0)).*__f)(static_cast<_Args&&>(__args)...)))
+ { return ((*static_cast<_A0&&>(__a0)).*__f)(static_cast<_Args&&>(__args)...); }
+
+// bullets 4, 5 and 6
+
+template <class _Fp, class _A0, class = __enable_if_bullet4<_Fp, _A0> >
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+decltype(std::declval<_A0>().*std::declval<_Fp>())
+__invoke(_Fp&& __f, _A0&& __a0)
+ _NOEXCEPT_(noexcept(static_cast<_A0&&>(__a0).*__f))
+ { return static_cast<_A0&&>(__a0).*__f; }
+
+template <class _Fp, class _A0, class = __enable_if_bullet5<_Fp, _A0> >
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+decltype(std::declval<_A0>().get().*std::declval<_Fp>())
+__invoke(_Fp&& __f, _A0&& __a0)
+ _NOEXCEPT_(noexcept(__a0.get().*__f))
+ { return __a0.get().*__f; }
+
+template <class _Fp, class _A0, class = __enable_if_bullet6<_Fp, _A0> >
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+decltype((*std::declval<_A0>()).*std::declval<_Fp>())
+__invoke(_Fp&& __f, _A0&& __a0)
+ _NOEXCEPT_(noexcept((*static_cast<_A0&&>(__a0)).*__f))
+ { return (*static_cast<_A0&&>(__a0)).*__f; }
+
+// bullet 7
+
+template <class _Fp, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
+decltype(std::declval<_Fp>()(std::declval<_Args>()...))
+__invoke(_Fp&& __f, _Args&&... __args)
+ _NOEXCEPT_(noexcept(static_cast<_Fp&&>(__f)(static_cast<_Args&&>(__args)...)))
+ { return static_cast<_Fp&&>(__f)(static_cast<_Args&&>(__args)...); }
+// clang-format on
+
+// __invokable
+template <class _Ret, class _Fp, class... _Args>
+struct __invokable_r {
+ template <class _XFp, class... _XArgs>
+ static decltype(std::__invoke(std::declval<_XFp>(), std::declval<_XArgs>()...)) __try_call(int);
+ template <class _XFp, class... _XArgs>
+ static __nat __try_call(...);
+
+ // FIXME: Check that _Ret, _Fp, and _Args... are all complete types, cv void,
+ // or incomplete array types as required by the standard.
+ using _Result = decltype(__try_call<_Fp, _Args...>(0));
+
+ using type = __conditional_t<_IsNotSame<_Result, __nat>::value,
+ __conditional_t<is_void<_Ret>::value, true_type, __is_core_convertible<_Result, _Ret> >,
+ false_type>;
+ static const bool value = type::value;
+};
+template <class _Fp, class... _Args>
+using __invokable = __invokable_r<void, _Fp, _Args...>;
+
+template <bool _IsInvokable, bool _IsCVVoid, class _Ret, class _Fp, class... _Args>
+struct __nothrow_invokable_r_imp {
+ static const bool value = false;
+};
+
+template <class _Ret, class _Fp, class... _Args>
+struct __nothrow_invokable_r_imp<true, false, _Ret, _Fp, _Args...> {
+ typedef __nothrow_invokable_r_imp _ThisT;
+
+ template <class _Tp>
+ static void __test_noexcept(_Tp) _NOEXCEPT;
+
+#ifdef _LIBCPP_CXX03_LANG
+ static const bool value = false;
+#else
+ static const bool value =
+ noexcept(_ThisT::__test_noexcept<_Ret>(std::__invoke(std::declval<_Fp>(), std::declval<_Args>()...)));
+#endif
+};
+
+template <class _Ret, class _Fp, class... _Args>
+struct __nothrow_invokable_r_imp<true, true, _Ret, _Fp, _Args...> {
+#ifdef _LIBCPP_CXX03_LANG
+ static const bool value = false;
+#else
+ static const bool value = noexcept(std::__invoke(std::declval<_Fp>(), std::declval<_Args>()...));
+#endif
+};
+
+template <class _Ret, class _Fp, class... _Args>
+using __nothrow_invokable_r =
+ __nothrow_invokable_r_imp<__invokable_r<_Ret, _Fp, _Args...>::value, is_void<_Ret>::value, _Ret, _Fp, _Args...>;
+
+template <class _Fp, class... _Args>
+using __nothrow_invokable = __nothrow_invokable_r_imp<__invokable<_Fp, _Args...>::value, true, void, _Fp, _Args...>;
+
+template <class _Fp, class... _Args>
+struct __invoke_of
+ : public enable_if<__invokable<_Fp, _Args...>::value, typename __invokable_r<void, _Fp, _Args...>::_Result> {};
+
+template <class _Ret, bool = is_void<_Ret>::value>
+struct __invoke_void_return_wrapper {
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static _Ret __call(_Args&&... __args) {
+ return std::__invoke(std::forward<_Args>(__args)...);
+ }
+};
+
+template <class _Ret>
+struct __invoke_void_return_wrapper<_Ret, true> {
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static void __call(_Args&&... __args) {
+ std::__invoke(std::forward<_Args>(__args)...);
+ }
+};
+
+#if _LIBCPP_STD_VER >= 17
+
+// is_invocable
+
+template <class _Fn, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS is_invocable : integral_constant<bool, __invokable<_Fn, _Args...>::value> {};
+
+template <class _Ret, class _Fn, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS is_invocable_r : integral_constant<bool, __invokable_r<_Ret, _Fn, _Args...>::value> {};
+
+template <class _Fn, class... _Args>
+inline constexpr bool is_invocable_v = is_invocable<_Fn, _Args...>::value;
+
+template <class _Ret, class _Fn, class... _Args>
+inline constexpr bool is_invocable_r_v = is_invocable_r<_Ret, _Fn, _Args...>::value;
+
+// is_nothrow_invocable
+
+template <class _Fn, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_invocable : integral_constant<bool, __nothrow_invokable<_Fn, _Args...>::value> {
+};
+
+template <class _Ret, class _Fn, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_invocable_r
+ : integral_constant<bool, __nothrow_invokable_r<_Ret, _Fn, _Args...>::value> {};
+
+template <class _Fn, class... _Args>
+inline constexpr bool is_nothrow_invocable_v = is_nothrow_invocable<_Fn, _Args...>::value;
+
+template <class _Ret, class _Fn, class... _Args>
+inline constexpr bool is_nothrow_invocable_r_v = is_nothrow_invocable_r<_Ret, _Fn, _Args...>::value;
+
+template <class _Fn, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS invoke_result : __invoke_of<_Fn, _Args...> {};
+
+template <class _Fn, class... _Args>
+using invoke_result_t = typename invoke_result<_Fn, _Args...>::type;
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_INVOKE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_abstract.h b/libcxx/include/__cxx03/__type_traits/is_abstract.h
new file mode 100644
index 00000000000000..4aa456be1c48e8
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_abstract.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_ABSTRACT_H
+#define _LIBCPP___TYPE_TRAITS_IS_ABSTRACT_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_abstract : public integral_constant<bool, __is_abstract(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_abstract_v = __is_abstract(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_ABSTRACT_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_aggregate.h b/libcxx/include/__cxx03/__type_traits/is_aggregate.h
new file mode 100644
index 00000000000000..4e0988071adeec
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_aggregate.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_AGGREGATE_H
+#define _LIBCPP___TYPE_TRAITS_IS_AGGREGATE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_aggregate : public integral_constant<bool, __is_aggregate(_Tp)> {};
+
+template <class _Tp>
+inline constexpr bool is_aggregate_v = __is_aggregate(_Tp);
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_AGGREGATE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_allocator.h b/libcxx/include/__cxx03/__type_traits/is_allocator.h
new file mode 100644
index 00000000000000..144ffac4d7ce5b
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_allocator.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_IS_ALLOCATOR_H
+#define _LIBCPP___TYPE_IS_ALLOCATOR_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <typename _Alloc, typename = void, typename = void>
+struct __is_allocator : false_type {};
+
+template <typename _Alloc>
+struct __is_allocator<_Alloc,
+ __void_t<typename _Alloc::value_type>,
+ __void_t<decltype(std::declval<_Alloc&>().allocate(size_t(0)))> > : true_type {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_IS_ALLOCATOR_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_always_bitcastable.h b/libcxx/include/__cxx03/__type_traits/is_always_bitcastable.h
new file mode 100644
index 00000000000000..5bc650b41358a8
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_always_bitcastable.h
@@ -0,0 +1,85 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_ALWAYS_BITCASTABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_ALWAYS_BITCASTABLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Checks whether an object of type `From` can always be bit-cast to an object of type `To` and represent a valid value
+// of type `To`. In other words, `From` and `To` have the same value representation and the set of values of `From` is
+// a subset of the set of values of `To`.
+//
+// Note that types that cannot be assigned to each other using built-in assignment (e.g. arrays) might still be
+// considered bit-castable.
+template <class _From, class _To>
+struct __is_always_bitcastable {
+ using _UnqualFrom = __remove_cv_t<_From>;
+ using _UnqualTo = __remove_cv_t<_To>;
+
+ // clang-format off
+ static const bool value =
+ // First, the simple case -- `From` and `To` are the same object type.
+ (is_same<_UnqualFrom, _UnqualTo>::value && is_trivially_copyable<_UnqualFrom>::value) ||
+
+ // Beyond the simple case, we say that one type is "always bit-castable" to another if:
+ // - (1) `From` and `To` have the same value representation, and in addition every possible value of `From` has
+ // a corresponding value in the `To` type (in other words, the set of values of `To` is a superset of the set of
+ // values of `From`);
+ // - (2) When the corresponding values are not the same value (as, for example, between an unsigned and a signed
+ // integer, where a large positive value of the unsigned integer corresponds to a negative value in the signed
+ // integer type), the value of `To` that results from a bitwise copy of `From` is the same what would be
+ // produced by the built-in assignment (if it were defined for the two types, to which there are minor
+ // exceptions, e.g. built-in arrays).
+ //
+ // In practice, that means:
+ // - all integral types (except `bool`, see below) -- that is, character types and `int` types, both signed and
+ // unsigned...
+ // - as well as arrays of such types...
+ // - ...that have the same size.
+ //
+ // Other trivially-copyable types can't be validly bit-cast outside of their own type:
+ // - floating-point types normally have different sizes and thus aren't bit-castable between each other (fails
+ // #1);
+ // - integral types and floating-point types use different representations, so for example bit-casting an integral
+ // `1` to `float` results in a very small less-than-one value, unlike built-in assignment that produces `1.0`
+ // (fails #2);
+ // - booleans normally use only a single bit of their object representation; bit-casting an integer to a boolean
+ // will result in a boolean object with an incorrect representation, which is undefined behavior (fails #2).
+ // Bit-casting from a boolean into an integer, however, is valid;
+ // - enumeration types may have different ranges of possible values (fails #1);
+ // - for pointers, it is not guaranteed that pointers to different types use the same set of values to represent
+ // addresses, and the conversion results are explicitly unspecified for types with different alignments
+ // (fails #1);
+ // - for structs and unions it is impossible to determine whether the set of values of one of them is a subset of
+ // the other (fails #1);
+ // - there is no need to consider `nullptr_t` for practical purposes.
+ (
+ sizeof(_From) == sizeof(_To) &&
+ is_integral<_From>::value &&
+ is_integral<_To>::value &&
+ !is_same<_UnqualTo, bool>::value
+ );
+ // clang-format on
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_ALWAYS_BITCASTABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_arithmetic.h b/libcxx/include/__cxx03/__type_traits/is_arithmetic.h
new file mode 100644
index 00000000000000..c9713e1840a7b1
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_arithmetic.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_ARITHMETIC_H
+#define _LIBCPP___TYPE_TRAITS_IS_ARITHMETIC_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_arithmetic
+ : public integral_constant<bool, is_integral<_Tp>::value || is_floating_point<_Tp>::value> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_ARITHMETIC_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_array.h b/libcxx/include/__cxx03/__type_traits/is_array.h
new file mode 100644
index 00000000000000..dc23de28d2c63b
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_array.h
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_ARRAY_H
+#define _LIBCPP___TYPE_TRAITS_IS_ARRAY_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_array) && \
+ (!defined(_LIBCPP_COMPILER_CLANG_BASED) || (defined(_LIBCPP_CLANG_VER) && _LIBCPP_CLANG_VER >= 1900))
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_array : _BoolConstant<__is_array(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_array_v = __is_array(_Tp);
+# endif
+
+#else
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_array : public false_type {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_array<_Tp[]> : public true_type {};
+template <class _Tp, size_t _Np>
+struct _LIBCPP_TEMPLATE_VIS is_array<_Tp[_Np]> : public true_type {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_array_v = is_array<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_array)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_ARRAY_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_assignable.h b/libcxx/include/__cxx03/__type_traits/is_assignable.h
new file mode 100644
index 00000000000000..cfb46997778782
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_assignable.h
@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_ASSIGNABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_ASSIGNABLE_H
+
+#include <__config>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_rvalue_reference.h>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Up>
+struct _LIBCPP_TEMPLATE_VIS is_assignable : _BoolConstant<__is_assignable(_Tp, _Up)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class _Arg>
+inline constexpr bool is_assignable_v = __is_assignable(_Tp, _Arg);
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_copy_assignable
+ : public integral_constant<bool,
+ __is_assignable(__add_lvalue_reference_t<_Tp>, __add_lvalue_reference_t<const _Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_copy_assignable_v = is_copy_assignable<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_move_assignable
+ : public integral_constant<bool, __is_assignable(__add_lvalue_reference_t<_Tp>, __add_rvalue_reference_t<_Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_move_assignable_v = is_move_assignable<_Tp>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_ASSIGNABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_base_of.h b/libcxx/include/__cxx03/__type_traits/is_base_of.h
new file mode 100644
index 00000000000000..090abeeb54dccb
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_base_of.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_BASE_OF_H
+#define _LIBCPP___TYPE_TRAITS_IS_BASE_OF_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Bp, class _Dp>
+struct _LIBCPP_TEMPLATE_VIS is_base_of : public integral_constant<bool, __is_base_of(_Bp, _Dp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Bp, class _Dp>
+inline constexpr bool is_base_of_v = __is_base_of(_Bp, _Dp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_BASE_OF_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_bounded_array.h b/libcxx/include/__cxx03/__type_traits/is_bounded_array.h
new file mode 100644
index 00000000000000..211403d638d08c
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_bounded_array.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_BOUNDED_ARRAY_H
+#define _LIBCPP___TYPE_TRAITS_IS_BOUNDED_ARRAY_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class>
+struct _LIBCPP_TEMPLATE_VIS __libcpp_is_bounded_array : false_type {};
+template <class _Tp, size_t _Np>
+struct _LIBCPP_TEMPLATE_VIS __libcpp_is_bounded_array<_Tp[_Np]> : true_type {};
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class>
+struct _LIBCPP_TEMPLATE_VIS is_bounded_array : false_type {};
+template <class _Tp, size_t _Np>
+struct _LIBCPP_TEMPLATE_VIS is_bounded_array<_Tp[_Np]> : true_type {};
+
+template <class _Tp>
+inline constexpr bool is_bounded_array_v = is_bounded_array<_Tp>::value;
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_BOUNDED_ARRAY_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_callable.h b/libcxx/include/__cxx03/__type_traits/is_callable.h
new file mode 100644
index 00000000000000..49724fe892ee55
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_callable.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_CALLABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_CALLABLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Func, class... _Args, class = decltype(std::declval<_Func>()(std::declval<_Args>()...))>
+true_type __is_callable_helper(int);
+template <class...>
+false_type __is_callable_helper(...);
+
+template <class _Func, class... _Args>
+struct __is_callable : decltype(std::__is_callable_helper<_Func, _Args...>(0)) {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_CALLABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_char_like_type.h b/libcxx/include/__cxx03/__type_traits/is_char_like_type.h
new file mode 100644
index 00000000000000..26205843047ca2
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_char_like_type.h
@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_CHAR_LIKE_TYPE_H
+#define _LIBCPP___TYPE_TRAITS_IS_CHAR_LIKE_TYPE_H
+
+#include <__config>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/is_standard_layout.h>
+#include <__type_traits/is_trivial.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT>
+using _IsCharLikeType = _And<is_standard_layout<_CharT>, is_trivial<_CharT> >;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_CHAR_LIKE_TYPE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_class.h b/libcxx/include/__cxx03/__type_traits/is_class.h
new file mode 100644
index 00000000000000..034f76a7865e3d
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_class.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_CLASS_H
+#define _LIBCPP___TYPE_TRAITS_IS_CLASS_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_class : public integral_constant<bool, __is_class(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_class_v = __is_class(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_CLASS_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_compound.h b/libcxx/include/__cxx03/__type_traits/is_compound.h
new file mode 100644
index 00000000000000..cd208ceab28863
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_compound.h
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_COMPOUND_H
+#define _LIBCPP___TYPE_TRAITS_IS_COMPOUND_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_fundamental.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_compound)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_compound : _BoolConstant<__is_compound(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_compound_v = __is_compound(_Tp);
+# endif
+
+#else // __has_builtin(__is_compound)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_compound : public integral_constant<bool, !is_fundamental<_Tp>::value> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_compound_v = is_compound<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_compound)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_COMPOUND_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_const.h b/libcxx/include/__cxx03/__type_traits/is_const.h
new file mode 100644
index 00000000000000..47ef70872b790a
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_const.h
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_CONST_H
+#define _LIBCPP___TYPE_TRAITS_IS_CONST_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_const)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_const : _BoolConstant<__is_const(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_const_v = __is_const(_Tp);
+# endif
+
+#else
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_const : public false_type {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_const<_Tp const> : public true_type {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_const_v = is_const<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_const)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_CONST_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_constant_evaluated.h b/libcxx/include/__cxx03/__type_traits/is_constant_evaluated.h
new file mode 100644
index 00000000000000..05e070a7478840
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_constant_evaluated.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_CONSTANT_EVALUATED_H
+#define _LIBCPP___TYPE_TRAITS_IS_CONSTANT_EVALUATED_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool is_constant_evaluated() noexcept {
+ return __builtin_is_constant_evaluated();
+}
+#endif
+
+_LIBCPP_HIDE_FROM_ABI inline _LIBCPP_CONSTEXPR bool __libcpp_is_constant_evaluated() _NOEXCEPT {
+ return __builtin_is_constant_evaluated();
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_CONSTANT_EVALUATED_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_constructible.h b/libcxx/include/__cxx03/__type_traits/is_constructible.h
new file mode 100644
index 00000000000000..567bd165c71520
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_constructible.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_IS_CONSTRUCTIBLE_H
+#define _LIBCPP___TYPE_IS_CONSTRUCTIBLE_H
+
+#include <__config>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_rvalue_reference.h>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS is_constructible : public integral_constant<bool, __is_constructible(_Tp, _Args...)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class... _Args>
+inline constexpr bool is_constructible_v = __is_constructible(_Tp, _Args...);
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_copy_constructible
+ : public integral_constant<bool, __is_constructible(_Tp, __add_lvalue_reference_t<const _Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_copy_constructible_v = is_copy_constructible<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_move_constructible
+ : public integral_constant<bool, __is_constructible(_Tp, __add_rvalue_reference_t<_Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_move_constructible_v = is_move_constructible<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_default_constructible : public integral_constant<bool, __is_constructible(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_default_constructible_v = __is_constructible(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_IS_CONSTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_convertible.h b/libcxx/include/__cxx03/__type_traits/is_convertible.h
new file mode 100644
index 00000000000000..414c2a6d6a0de0
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_convertible.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_CONVERTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_CONVERTIBLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _T1, class _T2>
+struct _LIBCPP_TEMPLATE_VIS is_convertible : public integral_constant<bool, __is_convertible(_T1, _T2)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _From, class _To>
+inline constexpr bool is_convertible_v = __is_convertible(_From, _To);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_CONVERTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_core_convertible.h b/libcxx/include/__cxx03/__type_traits/is_core_convertible.h
new file mode 100644
index 00000000000000..0de177c7771f4a
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_core_convertible.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_CORE_CONVERTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_CORE_CONVERTIBLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// [conv.general]/3 says "E is convertible to T" whenever "T t=E;" is well-formed.
+// We can't test for that, but we can test implicit convertibility by passing it
+// to a function. Notice that __is_core_convertible<void,void> is false,
+// and __is_core_convertible<immovable-type,immovable-type> is true in C++17 and later.
+
+template <class _Tp, class _Up, class = void>
+struct __is_core_convertible : public false_type {};
+
+template <class _Tp, class _Up>
+struct __is_core_convertible<_Tp, _Up, decltype(static_cast<void (*)(_Up)>(0)(static_cast<_Tp (*)()>(0)()))>
+ : public true_type {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_CORE_CONVERTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_destructible.h b/libcxx/include/__cxx03/__type_traits/is_destructible.h
new file mode 100644
index 00000000000000..3248b07d36ee67
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_destructible.h
@@ -0,0 +1,97 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_DESTRUCTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_DESTRUCTIBLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_all_extents.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_destructible)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_destructible : _BoolConstant<__is_destructible(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_destructible_v = __is_destructible(_Tp);
+# endif
+
+#else // __has_builtin(__is_destructible)
+
+// if it's a reference, return true
+// if it's a function, return false
+// if it's void, return false
+// if it's an array of unknown bound, return false
+// Otherwise, return "declval<_Up&>().~_Up()" is well-formed
+// where _Up is remove_all_extents<_Tp>::type
+
+template <class>
+struct __is_destructible_apply {
+ typedef int type;
+};
+
+template <typename _Tp>
+struct __is_destructor_wellformed {
+ template <typename _Tp1>
+ static true_type __test(typename __is_destructible_apply<decltype(std::declval<_Tp1&>().~_Tp1())>::type);
+
+ template <typename _Tp1>
+ static false_type __test(...);
+
+ static const bool value = decltype(__test<_Tp>(12))::value;
+};
+
+template <class _Tp, bool>
+struct __destructible_imp;
+
+template <class _Tp>
+struct __destructible_imp<_Tp, false>
+ : public integral_constant<bool, __is_destructor_wellformed<__remove_all_extents_t<_Tp> >::value> {};
+
+template <class _Tp>
+struct __destructible_imp<_Tp, true> : public true_type {};
+
+template <class _Tp, bool>
+struct __destructible_false;
+
+template <class _Tp>
+struct __destructible_false<_Tp, false> : public __destructible_imp<_Tp, is_reference<_Tp>::value> {};
+
+template <class _Tp>
+struct __destructible_false<_Tp, true> : public false_type {};
+
+template <class _Tp>
+struct is_destructible : public __destructible_false<_Tp, is_function<_Tp>::value> {};
+
+template <class _Tp>
+struct is_destructible<_Tp[]> : public false_type {};
+
+template <>
+struct is_destructible<void> : public false_type {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_destructible_v = is_destructible<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_destructible)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_DESTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_empty.h b/libcxx/include/__cxx03/__type_traits/is_empty.h
new file mode 100644
index 00000000000000..951d93b5a2f10e
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_empty.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_EMPTY_H
+#define _LIBCPP___TYPE_TRAITS_IS_EMPTY_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_empty : public integral_constant<bool, __is_empty(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_empty_v = __is_empty(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_EMPTY_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_enum.h b/libcxx/include/__cxx03/__type_traits/is_enum.h
new file mode 100644
index 00000000000000..2fab6db2c8d50f
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_enum.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_ENUM_H
+#define _LIBCPP___TYPE_TRAITS_IS_ENUM_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_enum : public integral_constant<bool, __is_enum(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_enum_v = __is_enum(_Tp);
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_scoped_enum : bool_constant<__is_scoped_enum(_Tp)> {};
+
+template <class _Tp>
+inline constexpr bool is_scoped_enum_v = __is_scoped_enum(_Tp);
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_ENUM_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_equality_comparable.h b/libcxx/include/__cxx03/__type_traits/is_equality_comparable.h
new file mode 100644
index 00000000000000..4397f743e5ee95
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_equality_comparable.h
@@ -0,0 +1,88 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_EQUALITY_COMPARABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_EQUALITY_COMPARABLE_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Up, class = void>
+struct __is_equality_comparable : false_type {};
+
+template <class _Tp, class _Up>
+struct __is_equality_comparable<_Tp, _Up, __void_t<decltype(std::declval<_Tp>() == std::declval<_Up>())> > : true_type {
+};
+
+// A type is_trivially_equality_comparable if the expression `a == b` is equivalent to `std::memcmp(&a, &b, sizeof(T))`
+// (with `a` and `b` being of type `T`). For the case where we compare two object of the same type, we can use
+// __is_trivially_equality_comparable. We have special-casing for pointers which point to the same type ignoring
+// cv-qualifications and comparing to void-pointers.
+//
+// The following types are not trivially equality comparable:
+// floating-point types: different bit-patterns can compare equal. (e.g 0.0 and -0.0)
+// enums: The user is allowed to specialize operator== for enums
+// pointers that don't have the same type (ignoring cv-qualifiers): pointers to virtual bases are equality comparable,
+// but don't have the same bit-pattern. An exception to this is comparing to a void-pointer. There the bit-pattern is
+// always compared.
+// objects with padding bytes: since objects with padding bytes may compare equal, even though their object
+// representation may not be equivalent.
+
+template <class _Tp, class _Up, class = void>
+struct __libcpp_is_trivially_equality_comparable_impl : false_type {};
+
+template <class _Tp>
+struct __libcpp_is_trivially_equality_comparable_impl<_Tp, _Tp>
+#if __has_builtin(__is_trivially_equality_comparable)
+ : integral_constant<bool, __is_trivially_equality_comparable(_Tp) && __is_equality_comparable<_Tp, _Tp>::value> {
+};
+#else
+ : is_integral<_Tp> {
+};
+#endif // __has_builtin(__is_trivially_equality_comparable)
+
+template <class _Tp, class _Up>
+struct __libcpp_is_trivially_equality_comparable_impl<
+ _Tp,
+ _Up,
+ __enable_if_t<is_integral<_Tp>::value && is_integral<_Up>::value && !is_same<_Tp, _Up>::value &&
+ is_signed<_Tp>::value == is_signed<_Up>::value && sizeof(_Tp) == sizeof(_Up)> > : true_type {};
+
+template <class _Tp>
+struct __libcpp_is_trivially_equality_comparable_impl<_Tp*, _Tp*> : true_type {};
+
+// TODO: Use is_pointer_inverconvertible_base_of
+template <class _Tp, class _Up>
+struct __libcpp_is_trivially_equality_comparable_impl<_Tp*, _Up*>
+ : integral_constant<
+ bool,
+ __is_equality_comparable<_Tp*, _Up*>::value &&
+ (is_same<__remove_cv_t<_Tp>, __remove_cv_t<_Up> >::value || is_void<_Tp>::value || is_void<_Up>::value)> {
+};
+
+template <class _Tp, class _Up>
+using __libcpp_is_trivially_equality_comparable =
+ __libcpp_is_trivially_equality_comparable_impl<__remove_cv_t<_Tp>, __remove_cv_t<_Up> >;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_EQUALITY_COMPARABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_execution_policy.h b/libcxx/include/__cxx03/__type_traits/is_execution_policy.h
new file mode 100644
index 00000000000000..6884f17ba16c88
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_execution_policy.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_EXECUTION_POLICY_H
+#define _LIBCPP___TYPE_TRAITS_IS_EXECUTION_POLICY_H
+
+#include <__config>
+#include <__type_traits/remove_cvref.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class>
+inline constexpr bool is_execution_policy_v = false;
+
+template <class>
+inline constexpr bool __is_unsequenced_execution_policy_impl = false;
+
+template <class _Tp>
+inline constexpr bool __is_unsequenced_execution_policy_v =
+ __is_unsequenced_execution_policy_impl<__remove_cvref_t<_Tp>>;
+
+template <class>
+inline constexpr bool __is_parallel_execution_policy_impl = false;
+
+template <class _Tp>
+inline constexpr bool __is_parallel_execution_policy_v = __is_parallel_execution_policy_impl<__remove_cvref_t<_Tp>>;
+
+namespace execution {
+struct __disable_user_instantiations_tag {
+ explicit __disable_user_instantiations_tag() = default;
+};
+} // namespace execution
+
+// TODO: Remove default argument once algorithms are using the new backend dispatching
+template <class _ExecutionPolicy>
+_LIBCPP_HIDE_FROM_ABI auto
+__remove_parallel_policy(const _ExecutionPolicy& = _ExecutionPolicy{execution::__disable_user_instantiations_tag{}});
+
+// Removes the "parallel" part of an execution policy.
+// For example, turns par_unseq into unseq, and par into seq.
+template <class _ExecutionPolicy>
+using __remove_parallel_policy_t = decltype(std::__remove_parallel_policy<_ExecutionPolicy>());
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_EXECUTION_POLICY_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_final.h b/libcxx/include/__cxx03/__type_traits/is_final.h
new file mode 100644
index 00000000000000..499c5e3a1edca4
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_final.h
@@ -0,0 +1,36 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_FINAL_H
+#define _LIBCPP___TYPE_TRAITS_IS_FINAL_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS __libcpp_is_final : public integral_constant<bool, __is_final(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_final : public integral_constant<bool, __is_final(_Tp)> {};
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_final_v = __is_final(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_FINAL_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_floating_point.h b/libcxx/include/__cxx03/__type_traits/is_floating_point.h
new file mode 100644
index 00000000000000..add34782dfa099
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_floating_point.h
@@ -0,0 +1,39 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_FLOATING_POINT_H
+#define _LIBCPP___TYPE_TRAITS_IS_FLOATING_POINT_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// clang-format off
+template <class _Tp> struct __libcpp_is_floating_point : public false_type {};
+template <> struct __libcpp_is_floating_point<float> : public true_type {};
+template <> struct __libcpp_is_floating_point<double> : public true_type {};
+template <> struct __libcpp_is_floating_point<long double> : public true_type {};
+// clang-format on
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_floating_point : public __libcpp_is_floating_point<__remove_cv_t<_Tp> > {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_floating_point_v = is_floating_point<_Tp>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_FLOATING_POINT_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_function.h b/libcxx/include/__cxx03/__type_traits/is_function.h
new file mode 100644
index 00000000000000..98fedd0ad96d9b
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_function.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_FUNCTIONAL_H
+#define _LIBCPP___TYPE_TRAITS_IS_FUNCTIONAL_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_function : integral_constant<bool, __is_function(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_function_v = __is_function(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_FUNCTIONAL_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_fundamental.h b/libcxx/include/__cxx03/__type_traits/is_fundamental.h
new file mode 100644
index 00000000000000..55f8e41f75f457
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_fundamental.h
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_FUNDAMENTAL_H
+#define _LIBCPP___TYPE_TRAITS_IS_FUNDAMENTAL_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_null_pointer.h>
+#include <__type_traits/is_void.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_fundamental)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_fundamental : _BoolConstant<__is_fundamental(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_fundamental_v = __is_fundamental(_Tp);
+# endif
+
+#else // __has_builtin(__is_fundamental)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_fundamental
+ : public integral_constant<bool, is_void<_Tp>::value || __is_null_pointer_v<_Tp> || is_arithmetic<_Tp>::value> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_fundamental_v = is_fundamental<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_fundamental)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_FUNDAMENTAL_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_implicitly_default_constructible.h b/libcxx/include/__cxx03/__type_traits/is_implicitly_default_constructible.h
new file mode 100644
index 00000000000000..d5dadd7b870dd9
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_implicitly_default_constructible.h
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_IMPLICITLY_DEFAULT_CONSTRUCTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_IMPLICITLY_DEFAULT_CONSTRUCTIBLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_constructible.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_CXX03_LANG
+// First of all, we can't implement this check in C++03 mode because the {}
+// default initialization syntax isn't valid.
+// Second, we implement the trait in a funny manner with two defaulted template
+// arguments to workaround Clang's PR43454.
+template <class _Tp>
+void __test_implicit_default_constructible(_Tp);
+
+template <class _Tp, class = void, class = typename is_default_constructible<_Tp>::type>
+struct __is_implicitly_default_constructible : false_type {};
+
+template <class _Tp>
+struct __is_implicitly_default_constructible<_Tp,
+ decltype(std::__test_implicit_default_constructible<_Tp const&>({})),
+ true_type> : true_type {};
+
+template <class _Tp>
+struct __is_implicitly_default_constructible<_Tp,
+ decltype(std::__test_implicit_default_constructible<_Tp const&>({})),
+ false_type> : false_type {};
+#endif // !C++03
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_IMPLICITLY_DEFAULT_CONSTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_integral.h b/libcxx/include/__cxx03/__type_traits/is_integral.h
new file mode 100644
index 00000000000000..26969885af8dfd
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_integral.h
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_INTEGRAL_H
+#define _LIBCPP___TYPE_TRAITS_IS_INTEGRAL_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// clang-format off
+template <class _Tp> struct __libcpp_is_integral { enum { value = 0 }; };
+template <> struct __libcpp_is_integral<bool> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<char> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<signed char> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<unsigned char> { enum { value = 1 }; };
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <> struct __libcpp_is_integral<wchar_t> { enum { value = 1 }; };
+#endif
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <> struct __libcpp_is_integral<char8_t> { enum { value = 1 }; };
+#endif
+template <> struct __libcpp_is_integral<char16_t> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<char32_t> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<short> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<unsigned short> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<int> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<unsigned int> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<long> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<unsigned long> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<long long> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<unsigned long long> { enum { value = 1 }; };
+#ifndef _LIBCPP_HAS_NO_INT128
+template <> struct __libcpp_is_integral<__int128_t> { enum { value = 1 }; };
+template <> struct __libcpp_is_integral<__uint128_t> { enum { value = 1 }; };
+#endif
+// clang-format on
+
+#if __has_builtin(__is_integral)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_integral : _BoolConstant<__is_integral(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_integral_v = __is_integral(_Tp);
+# endif
+
+#else
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_integral : public _BoolConstant<__libcpp_is_integral<__remove_cv_t<_Tp> >::value> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_integral_v = is_integral<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_integral)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_INTEGRAL_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_literal_type.h b/libcxx/include/__cxx03/__type_traits/is_literal_type.h
new file mode 100644
index 00000000000000..10e23bceffbda3
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_literal_type.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_LITERAL_TYPE
+#define _LIBCPP___TYPE_TRAITS_IS_LITERAL_TYPE
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_TYPE_TRAITS)
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS
+_LIBCPP_DEPRECATED_IN_CXX17 is_literal_type : public integral_constant<bool, __is_literal_type(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+_LIBCPP_DEPRECATED_IN_CXX17 inline constexpr bool is_literal_type_v = __is_literal_type(_Tp);
+# endif // _LIBCPP_STD_VER >= 17
+#endif // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_TYPE_TRAITS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_LITERAL_TYPE
diff --git a/libcxx/include/__cxx03/__type_traits/is_member_pointer.h b/libcxx/include/__cxx03/__type_traits/is_member_pointer.h
new file mode 100644
index 00000000000000..cc125e318cf919
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_member_pointer.h
@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_MEMBER_POINTER_H
+#define _LIBCPP___TYPE_TRAITS_IS_MEMBER_POINTER_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_member_pointer : _BoolConstant<__is_member_pointer(_Tp)> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_member_object_pointer : _BoolConstant<__is_member_object_pointer(_Tp)> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_member_function_pointer : _BoolConstant<__is_member_function_pointer(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_member_pointer_v = __is_member_pointer(_Tp);
+
+template <class _Tp>
+inline constexpr bool is_member_object_pointer_v = __is_member_object_pointer(_Tp);
+
+template <class _Tp>
+inline constexpr bool is_member_function_pointer_v = __is_member_function_pointer(_Tp);
+# endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_MEMBER_POINTER_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_nothrow_assignable.h b/libcxx/include/__cxx03/__type_traits/is_nothrow_assignable.h
new file mode 100644
index 00000000000000..7e00c741f83e30
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_nothrow_assignable.h
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_NOTHROW_ASSIGNABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_NOTHROW_ASSIGNABLE_H
+
+#include <__config>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_rvalue_reference.h>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Arg>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_assignable : public integral_constant<bool, __is_nothrow_assignable(_Tp, _Arg)> {
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class _Arg>
+inline constexpr bool is_nothrow_assignable_v = __is_nothrow_assignable(_Tp, _Arg);
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_copy_assignable
+ : public integral_constant<
+ bool,
+ __is_nothrow_assignable(__add_lvalue_reference_t<_Tp>, __add_lvalue_reference_t<const _Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_nothrow_copy_assignable_v = is_nothrow_copy_assignable<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_move_assignable
+ : public integral_constant<bool,
+ __is_nothrow_assignable(__add_lvalue_reference_t<_Tp>, __add_rvalue_reference_t<_Tp>)> {
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_nothrow_move_assignable_v = is_nothrow_move_assignable<_Tp>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_NOTHROW_ASSIGNABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_nothrow_constructible.h b/libcxx/include/__cxx03/__type_traits/is_nothrow_constructible.h
new file mode 100644
index 00000000000000..58d2b2475140b6
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_nothrow_constructible.h
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONSTRUCTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONSTRUCTIBLE_H
+
+#include <__config>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_rvalue_reference.h>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template < class _Tp, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
+ : public integral_constant<bool, __is_nothrow_constructible(_Tp, _Args...)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class... _Args>
+inline constexpr bool is_nothrow_constructible_v = is_nothrow_constructible<_Tp, _Args...>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_copy_constructible
+ : public integral_constant< bool, __is_nothrow_constructible(_Tp, __add_lvalue_reference_t<const _Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_nothrow_copy_constructible_v = is_nothrow_copy_constructible<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_move_constructible
+ : public integral_constant<bool, __is_nothrow_constructible(_Tp, __add_rvalue_reference_t<_Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_nothrow_move_constructible_v = is_nothrow_move_constructible<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_default_constructible
+ : public integral_constant<bool, __is_nothrow_constructible(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_nothrow_default_constructible_v = __is_nothrow_constructible(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONSTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_nothrow_convertible.h b/libcxx/include/__cxx03/__type_traits/is_nothrow_convertible.h
new file mode 100644
index 00000000000000..bfc5a94cbadec6
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_nothrow_convertible.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONVERTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONVERTIBLE_H
+
+#include <__config>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/disjunction.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/lazy.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+# if __has_builtin(__is_nothrow_convertible)
+
+template <class _Tp, class _Up>
+struct is_nothrow_convertible : bool_constant<__is_nothrow_convertible(_Tp, _Up)> {};
+
+template <class _Tp, class _Up>
+inline constexpr bool is_nothrow_convertible_v = __is_nothrow_convertible(_Tp, _Up);
+
+# else // __has_builtin(__is_nothrow_convertible)
+
+template <typename _Tp>
+void __test_noexcept(_Tp) noexcept;
+
+template <typename _Fm, typename _To>
+bool_constant<noexcept(std::__test_noexcept<_To>(std::declval<_Fm>()))> __is_nothrow_convertible_test();
+
+template <typename _Fm, typename _To>
+struct __is_nothrow_convertible_helper : decltype(__is_nothrow_convertible_test<_Fm, _To>()) {};
+
+template <typename _Fm, typename _To>
+struct is_nothrow_convertible
+ : _Or<_And<is_void<_To>, is_void<_Fm>>,
+ _Lazy<_And, is_convertible<_Fm, _To>, __is_nothrow_convertible_helper<_Fm, _To> > >::type {};
+
+template <typename _Fm, typename _To>
+inline constexpr bool is_nothrow_convertible_v = is_nothrow_convertible<_Fm, _To>::value;
+
+# endif // __has_builtin(__is_nothrow_convertible)
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONVERTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_nothrow_destructible.h b/libcxx/include/__cxx03/__type_traits/is_nothrow_destructible.h
new file mode 100644
index 00000000000000..c2d5ca87232aa1
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_nothrow_destructible.h
@@ -0,0 +1,63 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_NOTHROW_DESTRUCTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_NOTHROW_DESTRUCTIBLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_destructible.h>
+#include <__utility/declval.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_nothrow_destructible)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible : integral_constant<bool, __is_nothrow_destructible(_Tp)> {};
+
+#else
+
+template <bool, class _Tp>
+struct __libcpp_is_nothrow_destructible;
+
+template <class _Tp>
+struct __libcpp_is_nothrow_destructible<false, _Tp> : public false_type {};
+
+template <class _Tp>
+struct __libcpp_is_nothrow_destructible<true, _Tp>
+ : public integral_constant<bool, noexcept(std::declval<_Tp>().~_Tp()) > {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible
+ : public __libcpp_is_nothrow_destructible<is_destructible<_Tp>::value, _Tp> {};
+
+template <class _Tp, size_t _Ns>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible<_Tp[_Ns]> : public is_nothrow_destructible<_Tp> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible<_Tp&> : public true_type {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible<_Tp&&> : public true_type {};
+
+#endif // __has_builtin(__is_nothrow_destructible)
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_nothrow_destructible_v = is_nothrow_destructible<_Tp>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_NOTHROW_DESTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_null_pointer.h b/libcxx/include/__cxx03/__type_traits/is_null_pointer.h
new file mode 100644
index 00000000000000..9f5697e232684e
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_null_pointer.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_NULL_POINTER_H
+#define _LIBCPP___TYPE_TRAITS_IS_NULL_POINTER_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+inline const bool __is_null_pointer_v = __is_same(__remove_cv(_Tp), nullptr_t);
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_null_pointer : integral_constant<bool, __is_null_pointer_v<_Tp>> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_null_pointer_v = __is_null_pointer_v<_Tp>;
+# endif
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_NULL_POINTER_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_object.h b/libcxx/include/__cxx03/__type_traits/is_object.h
new file mode 100644
index 00000000000000..ec04508402ce51
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_object.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_OBJECT_H
+#define _LIBCPP___TYPE_TRAITS_IS_OBJECT_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_object : _BoolConstant<__is_object(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_object_v = __is_object(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_OBJECT_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_pod.h b/libcxx/include/__cxx03/__type_traits/is_pod.h
new file mode 100644
index 00000000000000..5888fbf457d8b1
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_pod.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_POD_H
+#define _LIBCPP___TYPE_TRAITS_IS_POD_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_pod : public integral_constant<bool, __is_pod(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_pod_v = __is_pod(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_POD_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_pointer.h b/libcxx/include/__cxx03/__type_traits/is_pointer.h
new file mode 100644
index 00000000000000..38eb7996c68642
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_pointer.h
@@ -0,0 +1,65 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_POINTER_H
+#define _LIBCPP___TYPE_TRAITS_IS_POINTER_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_pointer)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_pointer : _BoolConstant<__is_pointer(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_pointer_v = __is_pointer(_Tp);
+# endif
+
+#else // __has_builtin(__is_pointer)
+
+template <class _Tp>
+struct __libcpp_is_pointer : public false_type {};
+template <class _Tp>
+struct __libcpp_is_pointer<_Tp*> : public true_type {};
+
+template <class _Tp>
+struct __libcpp_remove_objc_qualifiers {
+ typedef _Tp type;
+};
+# if defined(_LIBCPP_HAS_OBJC_ARC)
+// clang-format off
+template <class _Tp> struct __libcpp_remove_objc_qualifiers<_Tp __strong> { typedef _Tp type; };
+template <class _Tp> struct __libcpp_remove_objc_qualifiers<_Tp __weak> { typedef _Tp type; };
+template <class _Tp> struct __libcpp_remove_objc_qualifiers<_Tp __autoreleasing> { typedef _Tp type; };
+template <class _Tp> struct __libcpp_remove_objc_qualifiers<_Tp __unsafe_unretained> { typedef _Tp type; };
+// clang-format on
+# endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_pointer
+ : public __libcpp_is_pointer<typename __libcpp_remove_objc_qualifiers<__remove_cv_t<_Tp> >::type> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_pointer_v = is_pointer<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_pointer)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_POINTER_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_polymorphic.h b/libcxx/include/__cxx03/__type_traits/is_polymorphic.h
new file mode 100644
index 00000000000000..d122e1c87775bd
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_polymorphic.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_POLYMORPHIC_H
+#define _LIBCPP___TYPE_TRAITS_IS_POLYMORPHIC_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_polymorphic : public integral_constant<bool, __is_polymorphic(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_polymorphic_v = __is_polymorphic(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_POLYMORPHIC_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_primary_template.h b/libcxx/include/__cxx03/__type_traits/is_primary_template.h
new file mode 100644
index 00000000000000..f308dfadc8ec89
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_primary_template.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_PRIMARY_TEMPLATE_H
+#define _LIBCPP___TYPE_TRAITS_IS_PRIMARY_TEMPLATE_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_valid_expansion.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+using __test_for_primary_template = __enable_if_t<_IsSame<_Tp, typename _Tp::__primary_template>::value>;
+
+template <class _Tp>
+using __is_primary_template = _IsValidExpansion<__test_for_primary_template, _Tp>;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_PRIMARY_TEMPLATE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_reference.h b/libcxx/include/__cxx03/__type_traits/is_reference.h
new file mode 100644
index 00000000000000..cc157a438e4913
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_reference.h
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_REFERENCE_H
+#define _LIBCPP___TYPE_TRAITS_IS_REFERENCE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_reference : _BoolConstant<__is_reference(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_reference_v = __is_reference(_Tp);
+#endif
+
+#if __has_builtin(__is_lvalue_reference) && __has_builtin(__is_rvalue_reference)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_lvalue_reference : _BoolConstant<__is_lvalue_reference(_Tp)> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_rvalue_reference : _BoolConstant<__is_rvalue_reference(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_lvalue_reference_v = __is_lvalue_reference(_Tp);
+template <class _Tp>
+inline constexpr bool is_rvalue_reference_v = __is_rvalue_reference(_Tp);
+# endif
+
+#else // __has_builtin(__is_lvalue_reference)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_lvalue_reference : public false_type {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_lvalue_reference<_Tp&> : public true_type {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_rvalue_reference : public false_type {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_rvalue_reference<_Tp&&> : public true_type {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_lvalue_reference_v = is_lvalue_reference<_Tp>::value;
+
+template <class _Tp>
+inline constexpr bool is_rvalue_reference_v = is_rvalue_reference<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_lvalue_reference)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_REFERENCE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_reference_wrapper.h b/libcxx/include/__cxx03/__type_traits/is_reference_wrapper.h
new file mode 100644
index 00000000000000..310a910040e8be
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_reference_wrapper.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_REFERENCE_WRAPPER_H
+#define _LIBCPP___TYPE_TRAITS_IS_REFERENCE_WRAPPER_H
+
+#include <__config>
+#include <__fwd/functional.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __is_reference_wrapper_impl : public false_type {};
+template <class _Tp>
+struct __is_reference_wrapper_impl<reference_wrapper<_Tp> > : public true_type {};
+template <class _Tp>
+struct __is_reference_wrapper : public __is_reference_wrapper_impl<__remove_cv_t<_Tp> > {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_ENABLE_IF_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_referenceable.h b/libcxx/include/__cxx03/__type_traits/is_referenceable.h
new file mode 100644
index 00000000000000..4b34ec25723173
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_referenceable.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_REFERENCEABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_REFERENCEABLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_referenceable)
+template <class _Tp>
+struct __libcpp_is_referenceable : integral_constant<bool, __is_referenceable(_Tp)> {};
+#else
+struct __libcpp_is_referenceable_impl {
+ template <class _Tp>
+ static _Tp& __test(int);
+ template <class _Tp>
+ static false_type __test(...);
+};
+
+template <class _Tp>
+struct __libcpp_is_referenceable
+ : integral_constant<bool, _IsNotSame<decltype(__libcpp_is_referenceable_impl::__test<_Tp>(0)), false_type>::value> {
+};
+#endif // __has_builtin(__is_referenceable)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_REFERENCEABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_same.h b/libcxx/include/__cxx03/__type_traits/is_same.h
new file mode 100644
index 00000000000000..9561b7b5d6da3c
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_same.h
@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_SAME_H
+#define _LIBCPP___TYPE_TRAITS_IS_SAME_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Up>
+struct _LIBCPP_TEMPLATE_VIS is_same : _BoolConstant<__is_same(_Tp, _Up)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class _Up>
+inline constexpr bool is_same_v = __is_same(_Tp, _Up);
+#endif
+
+// _IsSame<T,U> has the same effect as is_same<T,U> but instantiates fewer types:
+// is_same<A,B> and is_same<C,D> are guaranteed to be different types, but
+// _IsSame<A,B> and _IsSame<C,D> are the same type (namely, false_type).
+// Neither GCC nor Clang can mangle the __is_same builtin, so _IsSame
+// mustn't be directly used anywhere that contributes to name-mangling
+// (such as in a dependent return type).
+
+template <class _Tp, class _Up>
+using _IsSame = _BoolConstant<__is_same(_Tp, _Up)>;
+
+template <class _Tp, class _Up>
+using _IsNotSame = _BoolConstant<!__is_same(_Tp, _Up)>;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_SAME_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_scalar.h b/libcxx/include/__cxx03/__type_traits/is_scalar.h
new file mode 100644
index 00000000000000..455200de472089
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_scalar.h
@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_SCALAR_H
+#define _LIBCPP___TYPE_TRAITS_IS_SCALAR_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_enum.h>
+#include <__type_traits/is_member_pointer.h>
+#include <__type_traits/is_null_pointer.h>
+#include <__type_traits/is_pointer.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_scalar)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_scalar : _BoolConstant<__is_scalar(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_scalar_v = __is_scalar(_Tp);
+# endif
+
+#else // __has_builtin(__is_scalar)
+
+template <class _Tp>
+struct __is_block : false_type {};
+# if defined(_LIBCPP_HAS_EXTENSION_BLOCKS)
+template <class _Rp, class... _Args>
+struct __is_block<_Rp (^)(_Args...)> : true_type {};
+# endif
+
+// clang-format off
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_scalar
+ : public integral_constant<
+ bool, is_arithmetic<_Tp>::value ||
+ is_member_pointer<_Tp>::value ||
+ is_pointer<_Tp>::value ||
+ __is_null_pointer_v<_Tp> ||
+ __is_block<_Tp>::value ||
+ is_enum<_Tp>::value> {};
+// clang-format on
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS is_scalar<nullptr_t> : public true_type {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_scalar_v = is_scalar<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_scalar)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_SCALAR_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_signed.h b/libcxx/include/__cxx03/__type_traits/is_signed.h
new file mode 100644
index 00000000000000..fd6f93e1823627
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_signed.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_SIGNED_H
+#define _LIBCPP___TYPE_TRAITS_IS_SIGNED_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_signed)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_signed : _BoolConstant<__is_signed(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_signed_v = __is_signed(_Tp);
+# endif
+
+#else // __has_builtin(__is_signed)
+
+template <class _Tp, bool = is_integral<_Tp>::value>
+struct __libcpp_is_signed_impl : public _BoolConstant<(_Tp(-1) < _Tp(0))> {};
+
+template <class _Tp>
+struct __libcpp_is_signed_impl<_Tp, false> : public true_type {}; // floating point
+
+template <class _Tp, bool = is_arithmetic<_Tp>::value>
+struct __libcpp_is_signed : public __libcpp_is_signed_impl<_Tp> {};
+
+template <class _Tp>
+struct __libcpp_is_signed<_Tp, false> : public false_type {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_signed : public __libcpp_is_signed<_Tp> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_signed_v = is_signed<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_signed)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_SIGNED_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_signed_integer.h b/libcxx/include/__cxx03/__type_traits/is_signed_integer.h
new file mode 100644
index 00000000000000..467548d0aaafbd
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_signed_integer.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_SIGNED_INTEGER_H
+#define _LIBCPP___TYPE_TRAITS_IS_SIGNED_INTEGER_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// clang-format off
+template <class _Tp> struct __libcpp_is_signed_integer : public false_type {};
+template <> struct __libcpp_is_signed_integer<signed char> : public true_type {};
+template <> struct __libcpp_is_signed_integer<signed short> : public true_type {};
+template <> struct __libcpp_is_signed_integer<signed int> : public true_type {};
+template <> struct __libcpp_is_signed_integer<signed long> : public true_type {};
+template <> struct __libcpp_is_signed_integer<signed long long> : public true_type {};
+#ifndef _LIBCPP_HAS_NO_INT128
+template <> struct __libcpp_is_signed_integer<__int128_t> : public true_type {};
+#endif
+// clang-format on
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_SIGNED_INTEGER_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_specialization.h b/libcxx/include/__cxx03/__type_traits/is_specialization.h
new file mode 100644
index 00000000000000..9b75636b1a511f
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_specialization.h
@@ -0,0 +1,45 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_SPECIALIZATION
+#define _LIBCPP___TYPE_TRAITS_IS_SPECIALIZATION
+
+// This contains parts of P2098R1 but is based on MSVC STL's implementation.
+//
+// The paper has been rejected
+// We will not pursue P2098R0 (std::is_specialization_of) at this time; we'd
+// like to see a solution to this problem, but it requires language evolution
+// too.
+//
+// Since it is expected a real solution will be provided in the future only the
+// minimal part is implemented.
+//
+// Note a cvref qualified _Tp is never considered a specialization.
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Tp, template <class...> class _Template>
+inline constexpr bool __is_specialization_v = false; // true if and only if _Tp is a specialization of _Template
+
+template <template <class...> class _Template, class... _Args>
+inline constexpr bool __is_specialization_v<_Template<_Args...>, _Template> = true;
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_SPECIALIZATION
diff --git a/libcxx/include/__cxx03/__type_traits/is_standard_layout.h b/libcxx/include/__cxx03/__type_traits/is_standard_layout.h
new file mode 100644
index 00000000000000..76484f3e2a301f
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_standard_layout.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_STANDARD_LAYOUT_H
+#define _LIBCPP___TYPE_TRAITS_IS_STANDARD_LAYOUT_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_standard_layout : public integral_constant<bool, __is_standard_layout(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_standard_layout_v = __is_standard_layout(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_STANDARD_LAYOUT_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_swappable.h b/libcxx/include/__cxx03/__type_traits/is_swappable.h
new file mode 100644
index 00000000000000..0b817e65099339
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_swappable.h
@@ -0,0 +1,104 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_SWAPPABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_SWAPPABLE_H
+
+#include <__config>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Up, class = void>
+inline const bool __is_swappable_with_v = false;
+
+template <class _Tp>
+inline const bool __is_swappable_v = __is_swappable_with_v<_Tp&, _Tp&>;
+
+template <class _Tp, class _Up, bool = __is_swappable_with_v<_Tp, _Up> >
+inline const bool __is_nothrow_swappable_with_v = false;
+
+template <class _Tp>
+inline const bool __is_nothrow_swappable_v = __is_nothrow_swappable_with_v<_Tp&, _Tp&>;
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Tp>
+using __swap_result_t = __enable_if_t<is_move_constructible<_Tp>::value && is_move_assignable<_Tp>::value>;
+#else
+template <class>
+using __swap_result_t = void;
+#endif
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __swap_result_t<_Tp> swap(_Tp& __x, _Tp& __y)
+ _NOEXCEPT_(is_nothrow_move_constructible<_Tp>::value&& is_nothrow_move_assignable<_Tp>::value);
+
+template <class _Tp, size_t _Np, __enable_if_t<__is_swappable_v<_Tp>, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(_Tp (&__a)[_Np], _Tp (&__b)[_Np]) _NOEXCEPT_(__is_nothrow_swappable_v<_Tp>);
+
+// ALL generic swap overloads MUST already have a declaration available at this point.
+
+template <class _Tp, class _Up>
+inline const bool __is_swappable_with_v<_Tp,
+ _Up,
+ __void_t<decltype(swap(std::declval<_Tp>(), std::declval<_Up>())),
+ decltype(swap(std::declval<_Up>(), std::declval<_Tp>()))> > = true;
+
+#ifndef _LIBCPP_CXX03_LANG // C++03 doesn't have noexcept, so things are never nothrow swappable
+template <class _Tp, class _Up>
+inline const bool __is_nothrow_swappable_with_v<_Tp, _Up, true> =
+ noexcept(swap(std::declval<_Tp>(), std::declval<_Up>())) &&
+ noexcept(swap(std::declval<_Up>(), std::declval<_Tp>()));
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Tp, class _Up>
+inline constexpr bool is_swappable_with_v = __is_swappable_with_v<_Tp, _Up>;
+
+template <class _Tp, class _Up>
+struct _LIBCPP_TEMPLATE_VIS is_swappable_with : bool_constant<is_swappable_with_v<_Tp, _Up>> {};
+
+template <class _Tp>
+inline constexpr bool is_swappable_v =
+ is_swappable_with_v<__add_lvalue_reference_t<_Tp>, __add_lvalue_reference_t<_Tp>>;
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_swappable : bool_constant<is_swappable_v<_Tp>> {};
+
+template <class _Tp, class _Up>
+inline constexpr bool is_nothrow_swappable_with_v = __is_nothrow_swappable_with_v<_Tp, _Up>;
+
+template <class _Tp, class _Up>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_swappable_with : bool_constant<is_nothrow_swappable_with_v<_Tp, _Up>> {};
+
+template <class _Tp>
+inline constexpr bool is_nothrow_swappable_v =
+ is_nothrow_swappable_with_v<__add_lvalue_reference_t<_Tp>, __add_lvalue_reference_t<_Tp>>;
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_nothrow_swappable : bool_constant<is_nothrow_swappable_v<_Tp>> {};
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_SWAPPABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_trivial.h b/libcxx/include/__cxx03/__type_traits/is_trivial.h
new file mode 100644
index 00000000000000..0007c7446d5e5f
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_trivial.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_TRIVIAL_H
+#define _LIBCPP___TYPE_TRAITS_IS_TRIVIAL_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivial : public integral_constant<bool, __is_trivial(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_trivial_v = __is_trivial(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_TRIVIAL_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_trivially_assignable.h b/libcxx/include/__cxx03/__type_traits/is_trivially_assignable.h
new file mode 100644
index 00000000000000..201333b0fa0b33
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_trivially_assignable.h
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_ASSIGNABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_ASSIGNABLE_H
+
+#include <__config>
+#include <__type_traits/add_const.h>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_rvalue_reference.h>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Arg>
+struct is_trivially_assignable : integral_constant<bool, __is_trivially_assignable(_Tp, _Arg)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class _Arg>
+inline constexpr bool is_trivially_assignable_v = __is_trivially_assignable(_Tp, _Arg);
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_copy_assignable
+ : public integral_constant<
+ bool,
+ __is_trivially_assignable(__add_lvalue_reference_t<_Tp>, __add_lvalue_reference_t<const _Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_trivially_copy_assignable_v = is_trivially_copy_assignable<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_move_assignable
+ : public integral_constant<
+ bool,
+ __is_trivially_assignable(__add_lvalue_reference_t<_Tp>, __add_rvalue_reference_t<_Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_trivially_move_assignable_v = is_trivially_move_assignable<_Tp>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_ASSIGNABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_trivially_constructible.h b/libcxx/include/__cxx03/__type_traits/is_trivially_constructible.h
new file mode 100644
index 00000000000000..3a77e9fe164da1
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_trivially_constructible.h
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
+
+#include <__config>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_rvalue_reference.h>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class... _Args>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible
+ : integral_constant<bool, __is_trivially_constructible(_Tp, _Args...)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class... _Args>
+inline constexpr bool is_trivially_constructible_v = __is_trivially_constructible(_Tp, _Args...);
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_copy_constructible
+ : public integral_constant<bool, __is_trivially_constructible(_Tp, __add_lvalue_reference_t<const _Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_trivially_copy_constructible_v = is_trivially_copy_constructible<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_move_constructible
+ : public integral_constant<bool, __is_trivially_constructible(_Tp, __add_rvalue_reference_t<_Tp>)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_trivially_move_constructible_v = is_trivially_move_constructible<_Tp>::value;
+#endif
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_default_constructible
+ : public integral_constant<bool, __is_trivially_constructible(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_trivially_default_constructible_v = __is_trivially_constructible(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_trivially_copyable.h b/libcxx/include/__cxx03/__type_traits/is_trivially_copyable.h
new file mode 100644
index 00000000000000..e92af126ee94d9
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_trivially_copyable.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_copyable : public integral_constant<bool, __is_trivially_copyable(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_trivially_copyable_v = __is_trivially_copyable(_Tp);
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+inline constexpr bool __is_cheap_to_copy = is_trivially_copyable_v<_Tp> && sizeof(_Tp) <= sizeof(std::intmax_t);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_trivially_destructible.h b/libcxx/include/__cxx03/__type_traits/is_trivially_destructible.h
new file mode 100644
index 00000000000000..5f9652f2a5011c
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_trivially_destructible.h
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_destructible.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_trivially_destructible)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_destructible
+ : public integral_constant<bool, __is_trivially_destructible(_Tp)> {};
+
+#elif __has_builtin(__has_trivial_destructor)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_trivially_destructible
+ : public integral_constant<bool, is_destructible<_Tp>::value&& __has_trivial_destructor(_Tp)> {};
+
+#else
+
+# error is_trivially_destructible is not implemented
+
+#endif // __has_builtin(__is_trivially_destructible)
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_trivially_destructible_v = is_trivially_destructible<_Tp>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_trivially_lexicographically_comparable.h b/libcxx/include/__cxx03/__type_traits/is_trivially_lexicographically_comparable.h
new file mode 100644
index 00000000000000..a310ea1b87e30c
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_trivially_lexicographically_comparable.h
@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_LEXICOGRAPHICALLY_COMPARABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_LEXICOGRAPHICALLY_COMPARABLE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_unsigned.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// A type is_trivially_lexicographically_comparable if the expression `a <=> b` (or their pre-C++20 equivalents) is
+// equivalent to `std::memcmp(&a, &b, sizeof(T))` (with `a` and `b` being of type `T`). There is currently no builtin to
+// tell us whether that's the case for arbitrary types, so we can only do this for known types. Specifically, these are
+// currently unsigned integer types with a sizeof(T) == 1.
+//
+// bool is trivially lexicographically comparable, because e.g. false <=> true is valid code. Furthermore, the standard
+// says that [basic.fundamental] "Type bool is a distinct type that has the same object representation, value
+// representation, and alignment requirements as an implementation-defined unsigned integer type. The values of type
+// bool are true and false."
+// This means that bool has to be unsigned and has exactly two values. This means that having anything other than the
+// `true` or `false` value representations in a bool is UB.
+//
+// The following types are not trivially lexicographically comparable:
+// signed integer types: `char(-1) < char(1)`, but memcmp compares `unsigned char`s
+// unsigned integer types with sizeof(T) > 1: depending on the endianness, the LSB might be the first byte to be
+// compared. This means that when comparing unsigned(129) and unsigned(2)
+// using memcmp(), the result would be that 2 > 129.
+// TODO: Do we want to enable this on big-endian systems?
+
+template <class _Tp, class _Up>
+struct __libcpp_is_trivially_lexicographically_comparable
+ : integral_constant<bool,
+ is_same<__remove_cv_t<_Tp>, __remove_cv_t<_Up> >::value && sizeof(_Tp) == 1 &&
+ is_unsigned<_Tp>::value> {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_LEXICOGRAPHICALLY_COMPARABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_trivially_relocatable.h b/libcxx/include/__cxx03/__type_traits/is_trivially_relocatable.h
new file mode 100644
index 00000000000000..c0871731cc0016
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_trivially_relocatable.h
@@ -0,0 +1,42 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_RELOCATABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_RELOCATABLE_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_trivially_copyable.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// A type is trivially relocatable if a move construct + destroy of the original object is equivalent to
+// `memcpy(dst, src, sizeof(T))`.
+
+#if __has_builtin(__is_trivially_relocatable)
+template <class _Tp, class = void>
+struct __libcpp_is_trivially_relocatable : integral_constant<bool, __is_trivially_relocatable(_Tp)> {};
+#else
+template <class _Tp, class = void>
+struct __libcpp_is_trivially_relocatable : is_trivially_copyable<_Tp> {};
+#endif
+
+template <class _Tp>
+struct __libcpp_is_trivially_relocatable<_Tp,
+ __enable_if_t<is_same<_Tp, typename _Tp::__trivially_relocatable>::value> >
+ : true_type {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_TRIVIALLY_RELOCATABLE_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_unbounded_array.h b/libcxx/include/__cxx03/__type_traits/is_unbounded_array.h
new file mode 100644
index 00000000000000..d58bb09e104285
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_unbounded_array.h
@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_UNBOUNDED_ARRAY_H
+#define _LIBCPP___TYPE_TRAITS_IS_UNBOUNDED_ARRAY_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class>
+struct _LIBCPP_TEMPLATE_VIS __libcpp_is_unbounded_array : false_type {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS __libcpp_is_unbounded_array<_Tp[]> : true_type {};
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class>
+struct _LIBCPP_TEMPLATE_VIS is_unbounded_array : false_type {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_unbounded_array<_Tp[]> : true_type {};
+
+template <class _Tp>
+inline constexpr bool is_unbounded_array_v = is_unbounded_array<_Tp>::value;
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_UNBOUNDED_ARRAY_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_union.h b/libcxx/include/__cxx03/__type_traits/is_union.h
new file mode 100644
index 00000000000000..1f009d993545ba
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_union.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_UNION_H
+#define _LIBCPP___TYPE_TRAITS_IS_UNION_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_union : public integral_constant<bool, __is_union(_Tp)> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_union_v = __is_union(_Tp);
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_UNION_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_unsigned.h b/libcxx/include/__cxx03/__type_traits/is_unsigned.h
new file mode 100644
index 00000000000000..48c5751ed70d8e
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_unsigned.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_H
+#define _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_integral.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_unsigned)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_unsigned : _BoolConstant<__is_unsigned(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_unsigned_v = __is_unsigned(_Tp);
+# endif
+
+#else // __has_builtin(__is_unsigned)
+
+template <class _Tp, bool = is_integral<_Tp>::value>
+struct __libcpp_is_unsigned_impl : public _BoolConstant<(_Tp(0) < _Tp(-1))> {};
+
+template <class _Tp>
+struct __libcpp_is_unsigned_impl<_Tp, false> : public false_type {}; // floating point
+
+template <class _Tp, bool = is_arithmetic<_Tp>::value>
+struct __libcpp_is_unsigned : public __libcpp_is_unsigned_impl<_Tp> {};
+
+template <class _Tp>
+struct __libcpp_is_unsigned<_Tp, false> : public false_type {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_unsigned : public __libcpp_is_unsigned<_Tp> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_unsigned_v = is_unsigned<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_unsigned)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_unsigned_integer.h b/libcxx/include/__cxx03/__type_traits/is_unsigned_integer.h
new file mode 100644
index 00000000000000..265894b32d4fc1
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_unsigned_integer.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_INTEGER_H
+#define _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_INTEGER_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// clang-format off
+template <class _Tp> struct __libcpp_is_unsigned_integer : public false_type {};
+template <> struct __libcpp_is_unsigned_integer<unsigned char> : public true_type {};
+template <> struct __libcpp_is_unsigned_integer<unsigned short> : public true_type {};
+template <> struct __libcpp_is_unsigned_integer<unsigned int> : public true_type {};
+template <> struct __libcpp_is_unsigned_integer<unsigned long> : public true_type {};
+template <> struct __libcpp_is_unsigned_integer<unsigned long long> : public true_type {};
+#ifndef _LIBCPP_HAS_NO_INT128
+template <> struct __libcpp_is_unsigned_integer<__uint128_t> : public true_type {};
+#endif
+// clang-format on
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_INTEGER_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_valid_expansion.h b/libcxx/include/__cxx03/__type_traits/is_valid_expansion.h
new file mode 100644
index 00000000000000..346bc98b110ffa
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_valid_expansion.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_VALID_EXPANSION_H
+#define _LIBCPP___TYPE_TRAITS_IS_VALID_EXPANSION_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <template <class...> class _Templ, class... _Args, class = _Templ<_Args...> >
+true_type __sfinae_test_impl(int);
+template <template <class...> class, class...>
+false_type __sfinae_test_impl(...);
+
+template <template <class...> class _Templ, class... _Args>
+using _IsValidExpansion _LIBCPP_NODEBUG = decltype(std::__sfinae_test_impl<_Templ, _Args...>(0));
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_VALID_EXPANSION_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_void.h b/libcxx/include/__cxx03/__type_traits/is_void.h
new file mode 100644
index 00000000000000..46316b0d3a534e
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_void.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_VOID_H
+#define _LIBCPP___TYPE_TRAITS_IS_VOID_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_void : _BoolConstant<__is_same(__remove_cv(_Tp), void)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_void_v = __is_same(__remove_cv(_Tp), void);
+# endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_VOID_H
diff --git a/libcxx/include/__cxx03/__type_traits/is_volatile.h b/libcxx/include/__cxx03/__type_traits/is_volatile.h
new file mode 100644
index 00000000000000..87960a819c8fcb
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/is_volatile.h
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_VOLATILE_H
+#define _LIBCPP___TYPE_TRAITS_IS_VOLATILE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__is_volatile)
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_volatile : _BoolConstant<__is_volatile(_Tp)> {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_volatile_v = __is_volatile(_Tp);
+# endif
+
+#else
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_volatile : public false_type {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS is_volatile<_Tp volatile> : public true_type {};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr bool is_volatile_v = is_volatile<_Tp>::value;
+# endif
+
+#endif // __has_builtin(__is_volatile)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_VOLATILE_H
diff --git a/libcxx/include/__cxx03/__type_traits/lazy.h b/libcxx/include/__cxx03/__type_traits/lazy.h
new file mode 100644
index 00000000000000..80826f1d64f604
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/lazy.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_LAZY_H
+#define _LIBCPP___TYPE_TRAITS_LAZY_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <template <class...> class _Func, class... _Args>
+struct _Lazy : _Func<_Args...> {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_LAZY_H
diff --git a/libcxx/include/__cxx03/__type_traits/make_32_64_or_128_bit.h b/libcxx/include/__cxx03/__type_traits/make_32_64_or_128_bit.h
new file mode 100644
index 00000000000000..f7f2e81735dafd
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/make_32_64_or_128_bit.h
@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_MAKE_32_64_OR_128_BIT_H
+#define _LIBCPP___TYPE_TRAITS_MAKE_32_64_OR_128_BIT_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/is_unsigned.h>
+#include <__type_traits/make_unsigned.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+/// Helper to promote an integral to smallest 32, 64, or 128 bit representation.
+///
+/// The restriction is the same as the integral version of to_char.
+template <class _Tp>
+#if _LIBCPP_STD_VER >= 20
+ requires(is_signed_v<_Tp> || is_unsigned_v<_Tp> || is_same_v<_Tp, char>)
+#endif
+// clang-format off
+using __make_32_64_or_128_bit_t =
+ __copy_unsigned_t<_Tp,
+ __conditional_t<sizeof(_Tp) <= sizeof(int32_t), int32_t,
+ __conditional_t<sizeof(_Tp) <= sizeof(int64_t), int64_t,
+#ifndef _LIBCPP_HAS_NO_INT128
+ __conditional_t<sizeof(_Tp) <= sizeof(__int128_t), __int128_t,
+ /* else */ void>
+#else
+ /* else */ void
+#endif
+ > > >;
+// clang-format on
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_MAKE_32_64_OR_128_BIT_H
diff --git a/libcxx/include/__cxx03/__type_traits/make_const_lvalue_ref.h b/libcxx/include/__cxx03/__type_traits/make_const_lvalue_ref.h
new file mode 100644
index 00000000000000..469d4cb31ef7d6
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/make_const_lvalue_ref.h
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_MAKE_CONST_LVALUE_REF_H
+#define _LIBCPP___TYPE_TRAITS_MAKE_CONST_LVALUE_REF_H
+
+#include <__config>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+using __make_const_lvalue_ref = const __libcpp_remove_reference_t<_Tp>&;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_MAKE_CONST_LVALUE_REF_H
diff --git a/libcxx/include/__cxx03/__type_traits/make_signed.h b/libcxx/include/__cxx03/__type_traits/make_signed.h
new file mode 100644
index 00000000000000..d09d6ed4a1e7cc
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/make_signed.h
@@ -0,0 +1,89 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_MAKE_SIGNED_H
+#define _LIBCPP___TYPE_TRAITS_MAKE_SIGNED_H
+
+#include <__config>
+#include <__type_traits/copy_cv.h>
+#include <__type_traits/is_enum.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/nat.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/type_list.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__make_signed)
+
+template <class _Tp>
+using __make_signed_t = __make_signed(_Tp);
+
+#else
+// clang-format off
+typedef __type_list<signed char,
+ __type_list<signed short,
+ __type_list<signed int,
+ __type_list<signed long,
+ __type_list<signed long long,
+# ifndef _LIBCPP_HAS_NO_INT128
+ __type_list<__int128_t,
+# endif
+ __nat
+# ifndef _LIBCPP_HAS_NO_INT128
+ >
+# endif
+ > > > > > __signed_types;
+// clang-format on
+
+template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
+struct __make_signed{};
+
+template <class _Tp>
+struct __make_signed<_Tp, true> {
+ typedef typename __find_first<__signed_types, sizeof(_Tp)>::type type;
+};
+
+// clang-format off
+template <> struct __make_signed<bool, true> {};
+template <> struct __make_signed< signed short, true> {typedef short type;};
+template <> struct __make_signed<unsigned short, true> {typedef short type;};
+template <> struct __make_signed< signed int, true> {typedef int type;};
+template <> struct __make_signed<unsigned int, true> {typedef int type;};
+template <> struct __make_signed< signed long, true> {typedef long type;};
+template <> struct __make_signed<unsigned long, true> {typedef long type;};
+template <> struct __make_signed< signed long long, true> {typedef long long type;};
+template <> struct __make_signed<unsigned long long, true> {typedef long long type;};
+# ifndef _LIBCPP_HAS_NO_INT128
+template <> struct __make_signed<__int128_t, true> {typedef __int128_t type;};
+template <> struct __make_signed<__uint128_t, true> {typedef __int128_t type;};
+# endif
+// clang-format on
+
+template <class _Tp>
+using __make_signed_t = __copy_cv_t<_Tp, typename __make_signed<__remove_cv_t<_Tp> >::type>;
+
+#endif // __has_builtin(__make_signed)
+
+template <class _Tp>
+struct make_signed {
+ using type _LIBCPP_NODEBUG = __make_signed_t<_Tp>;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using make_signed_t = __make_signed_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_MAKE_SIGNED_H
diff --git a/libcxx/include/__cxx03/__type_traits/make_unsigned.h b/libcxx/include/__cxx03/__type_traits/make_unsigned.h
new file mode 100644
index 00000000000000..282cd2d9113166
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/make_unsigned.h
@@ -0,0 +1,101 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_MAKE_UNSIGNED_H
+#define _LIBCPP___TYPE_TRAITS_MAKE_UNSIGNED_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/copy_cv.h>
+#include <__type_traits/is_enum.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_unsigned.h>
+#include <__type_traits/nat.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/type_list.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__make_unsigned)
+
+template <class _Tp>
+using __make_unsigned_t = __make_unsigned(_Tp);
+
+#else
+// clang-format off
+typedef __type_list<unsigned char,
+ __type_list<unsigned short,
+ __type_list<unsigned int,
+ __type_list<unsigned long,
+ __type_list<unsigned long long,
+# ifndef _LIBCPP_HAS_NO_INT128
+ __type_list<__uint128_t,
+# endif
+ __nat
+# ifndef _LIBCPP_HAS_NO_INT128
+ >
+# endif
+ > > > > > __unsigned_types;
+// clang-format on
+
+template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
+struct __make_unsigned{};
+
+template <class _Tp>
+struct __make_unsigned<_Tp, true> {
+ typedef typename __find_first<__unsigned_types, sizeof(_Tp)>::type type;
+};
+
+// clang-format off
+template <> struct __make_unsigned<bool, true> {};
+template <> struct __make_unsigned< signed short, true> {typedef unsigned short type;};
+template <> struct __make_unsigned<unsigned short, true> {typedef unsigned short type;};
+template <> struct __make_unsigned< signed int, true> {typedef unsigned int type;};
+template <> struct __make_unsigned<unsigned int, true> {typedef unsigned int type;};
+template <> struct __make_unsigned< signed long, true> {typedef unsigned long type;};
+template <> struct __make_unsigned<unsigned long, true> {typedef unsigned long type;};
+template <> struct __make_unsigned< signed long long, true> {typedef unsigned long long type;};
+template <> struct __make_unsigned<unsigned long long, true> {typedef unsigned long long type;};
+# ifndef _LIBCPP_HAS_NO_INT128
+template <> struct __make_unsigned<__int128_t, true> {typedef __uint128_t type;};
+template <> struct __make_unsigned<__uint128_t, true> {typedef __uint128_t type;};
+# endif
+// clang-format on
+
+template <class _Tp>
+using __make_unsigned_t = __copy_cv_t<_Tp, typename __make_unsigned<__remove_cv_t<_Tp> >::type>;
+
+#endif // __has_builtin(__make_unsigned)
+
+template <class _Tp>
+struct make_unsigned {
+ using type _LIBCPP_NODEBUG = __make_unsigned_t<_Tp>;
+};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using make_unsigned_t = __make_unsigned_t<_Tp>;
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr __make_unsigned_t<_Tp> __to_unsigned_like(_Tp __x) noexcept {
+ return static_cast<__make_unsigned_t<_Tp> >(__x);
+}
+#endif
+
+template <class _Tp, class _Up>
+using __copy_unsigned_t = __conditional_t<is_unsigned<_Tp>::value, __make_unsigned_t<_Up>, _Up>;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_MAKE_UNSIGNED_H
diff --git a/libcxx/include/__cxx03/__type_traits/maybe_const.h b/libcxx/include/__cxx03/__type_traits/maybe_const.h
new file mode 100644
index 00000000000000..25fba58fb77303
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/maybe_const.h
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_MAYBE_CONST_H
+#define _LIBCPP___TYPE_TRAITS_MAYBE_CONST_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <bool _Const, class _Tp>
+using __maybe_const = __conditional_t<_Const, const _Tp, _Tp>;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_MAYBE_CONST_H
diff --git a/libcxx/include/__cxx03/__type_traits/nat.h b/libcxx/include/__cxx03/__type_traits/nat.h
new file mode 100644
index 00000000000000..9f39b806814e26
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/nat.h
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_NAT_H
+#define _LIBCPP___TYPE_TRAITS_NAT_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __nat {
+#ifndef _LIBCPP_CXX03_LANG
+ __nat() = delete;
+ __nat(const __nat&) = delete;
+ __nat& operator=(const __nat&) = delete;
+ ~__nat() = delete;
+#endif
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_NAT_H
diff --git a/libcxx/include/__cxx03/__type_traits/negation.h b/libcxx/include/__cxx03/__type_traits/negation.h
new file mode 100644
index 00000000000000..a72e62d3f96e0c
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/negation.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_NEGATION_H
+#define _LIBCPP___TYPE_TRAITS_NEGATION_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Pred>
+struct _Not : _BoolConstant<!_Pred::value> {};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+struct negation : _Not<_Tp> {};
+template <class _Tp>
+inline constexpr bool negation_v = !_Tp::value;
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_NEGATION_H
diff --git a/libcxx/include/__cxx03/__type_traits/noexcept_move_assign_container.h b/libcxx/include/__cxx03/__type_traits/noexcept_move_assign_container.h
new file mode 100644
index 00000000000000..baaf36d9980e94
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/noexcept_move_assign_container.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_NOEXCEPT_MOVE_ASSIGN_CONTAINER_H
+#define _LIBCPP___TYPE_TRAITS_NOEXCEPT_MOVE_ASSIGN_CONTAINER_H
+
+#include <__config>
+#include <__memory/allocator_traits.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_nothrow_assignable.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <typename _Alloc, typename _Traits = allocator_traits<_Alloc> >
+struct __noexcept_move_assign_container
+ : public integral_constant<bool,
+ _Traits::propagate_on_container_move_assignment::value
+#if _LIBCPP_STD_VER >= 17
+ || _Traits::is_always_equal::value
+#else
+ && is_nothrow_move_assignable<_Alloc>::value
+#endif
+ > {
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_NOEXCEPT_MOVE_ASSIGN_CONTAINER_H
diff --git a/libcxx/include/__cxx03/__type_traits/promote.h b/libcxx/include/__cxx03/__type_traits/promote.h
new file mode 100644
index 00000000000000..2b2a6843b91502
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/promote.h
@@ -0,0 +1,128 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_PROMOTE_H
+#define _LIBCPP___TYPE_TRAITS_PROMOTE_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_arithmetic.h>
+
+#if defined(_LIBCPP_CLANG_VER) && _LIBCPP_CLANG_VER == 1700
+# include <__type_traits/is_same.h>
+# include <__utility/declval.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// TODO(LLVM-20): Remove this workaround
+#if !defined(_LIBCPP_CLANG_VER) || _LIBCPP_CLANG_VER != 1700
+
+template <class... _Args>
+class __promote {
+ static_assert((is_arithmetic<_Args>::value && ...));
+
+ static float __test(float);
+ static double __test(char);
+ static double __test(int);
+ static double __test(unsigned);
+ static double __test(long);
+ static double __test(unsigned long);
+ static double __test(long long);
+ static double __test(unsigned long long);
+# ifndef _LIBCPP_HAS_NO_INT128
+ static double __test(__int128_t);
+ static double __test(__uint128_t);
+# endif
+ static double __test(double);
+ static long double __test(long double);
+
+public:
+ using type = decltype((__test(_Args()) + ...));
+};
+
+#else
+
+template <class _Tp>
+struct __numeric_type {
+ static void __test(...);
+ static float __test(float);
+ static double __test(char);
+ static double __test(int);
+ static double __test(unsigned);
+ static double __test(long);
+ static double __test(unsigned long);
+ static double __test(long long);
+ static double __test(unsigned long long);
+# ifndef _LIBCPP_HAS_NO_INT128
+ static double __test(__int128_t);
+ static double __test(__uint128_t);
+# endif
+ static double __test(double);
+ static long double __test(long double);
+
+ typedef decltype(__test(std::declval<_Tp>())) type;
+ static const bool value = _IsNotSame<type, void>::value;
+};
+
+template <>
+struct __numeric_type<void> {
+ static const bool value = true;
+};
+
+template <class _A1,
+ class _A2 = void,
+ class _A3 = void,
+ bool = __numeric_type<_A1>::value && __numeric_type<_A2>::value && __numeric_type<_A3>::value>
+class __promote_imp {
+public:
+ static const bool value = false;
+};
+
+template <class _A1, class _A2, class _A3>
+class __promote_imp<_A1, _A2, _A3, true> {
+private:
+ typedef typename __promote_imp<_A1>::type __type1;
+ typedef typename __promote_imp<_A2>::type __type2;
+ typedef typename __promote_imp<_A3>::type __type3;
+
+public:
+ typedef decltype(__type1() + __type2() + __type3()) type;
+ static const bool value = true;
+};
+
+template <class _A1, class _A2>
+class __promote_imp<_A1, _A2, void, true> {
+private:
+ typedef typename __promote_imp<_A1>::type __type1;
+ typedef typename __promote_imp<_A2>::type __type2;
+
+public:
+ typedef decltype(__type1() + __type2()) type;
+ static const bool value = true;
+};
+
+template <class _A1>
+class __promote_imp<_A1, void, void, true> {
+public:
+ typedef typename __numeric_type<_A1>::type type;
+ static const bool value = true;
+};
+
+template <class _A1, class _A2 = void, class _A3 = void>
+class __promote : public __promote_imp<_A1, _A2, _A3> {};
+
+#endif // !defined(_LIBCPP_CLANG_VER) || _LIBCPP_CLANG_VER >= 1700
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_PROMOTE_H
diff --git a/libcxx/include/__cxx03/__type_traits/rank.h b/libcxx/include/__cxx03/__type_traits/rank.h
new file mode 100644
index 00000000000000..7f6fad1c540245
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/rank.h
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_RANK_H
+#define _LIBCPP___TYPE_TRAITS_RANK_H
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// TODO: Enable using the builtin __array_rank when https://llvm.org/PR57133 is resolved
+#if __has_builtin(__array_rank) && 0
+
+template <class _Tp>
+struct rank : integral_constant<size_t, __array_rank(_Tp)> {};
+
+#else
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS rank : public integral_constant<size_t, 0> {};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS rank<_Tp[]> : public integral_constant<size_t, rank<_Tp>::value + 1> {};
+template <class _Tp, size_t _Np>
+struct _LIBCPP_TEMPLATE_VIS rank<_Tp[_Np]> : public integral_constant<size_t, rank<_Tp>::value + 1> {};
+
+#endif // __has_builtin(__array_rank)
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+inline constexpr size_t rank_v = rank<_Tp>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_RANK_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_all_extents.h b/libcxx/include/__cxx03/__type_traits/remove_all_extents.h
new file mode 100644
index 00000000000000..d5373b51f52215
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_all_extents.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__remove_all_extents)
+template <class _Tp>
+struct remove_all_extents {
+ using type _LIBCPP_NODEBUG = __remove_all_extents(_Tp);
+};
+
+template <class _Tp>
+using __remove_all_extents_t = __remove_all_extents(_Tp);
+#else
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_all_extents {
+ typedef _Tp type;
+};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_all_extents<_Tp[]> {
+ typedef typename remove_all_extents<_Tp>::type type;
+};
+template <class _Tp, size_t _Np>
+struct _LIBCPP_TEMPLATE_VIS remove_all_extents<_Tp[_Np]> {
+ typedef typename remove_all_extents<_Tp>::type type;
+};
+
+template <class _Tp>
+using __remove_all_extents_t = typename remove_all_extents<_Tp>::type;
+#endif // __has_builtin(__remove_all_extents)
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using remove_all_extents_t = __remove_all_extents_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_const.h b/libcxx/include/__cxx03/__type_traits/remove_const.h
new file mode 100644
index 00000000000000..a3f0648c478506
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_const.h
@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_CONST_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_CONST_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__remove_const)
+template <class _Tp>
+struct remove_const {
+ using type _LIBCPP_NODEBUG = __remove_const(_Tp);
+};
+
+template <class _Tp>
+using __remove_const_t = __remove_const(_Tp);
+#else
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_const {
+ typedef _Tp type;
+};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_const<const _Tp> {
+ typedef _Tp type;
+};
+
+template <class _Tp>
+using __remove_const_t = typename remove_const<_Tp>::type;
+#endif // __has_builtin(__remove_const)
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using remove_const_t = __remove_const_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_CONST_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_const_ref.h b/libcxx/include/__cxx03/__type_traits/remove_const_ref.h
new file mode 100644
index 00000000000000..d3b334935a5b15
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_const_ref.h
@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_CONST_REF_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_CONST_REF_H
+
+#include <__config>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+using __remove_const_ref_t = __remove_const_t<__libcpp_remove_reference_t<_Tp> >;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_CONST_REF_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_cv.h b/libcxx/include/__cxx03/__type_traits/remove_cv.h
new file mode 100644
index 00000000000000..c4bf612794bd55
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_cv.h
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_CV_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_CV_H
+
+#include <__config>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_volatile.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__remove_cv) && !defined(_LIBCPP_COMPILER_GCC)
+template <class _Tp>
+struct remove_cv {
+ using type _LIBCPP_NODEBUG = __remove_cv(_Tp);
+};
+
+template <class _Tp>
+using __remove_cv_t = __remove_cv(_Tp);
+#else
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_cv {
+ typedef __remove_volatile_t<__remove_const_t<_Tp> > type;
+};
+
+template <class _Tp>
+using __remove_cv_t = __remove_volatile_t<__remove_const_t<_Tp> >;
+#endif // __has_builtin(__remove_cv)
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using remove_cv_t = __remove_cv_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_CV_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_cvref.h b/libcxx/include/__cxx03/__type_traits/remove_cvref.h
new file mode 100644
index 00000000000000..e8e8745ab09609
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_cvref.h
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_CVREF_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_CVREF_H
+
+#include <__config>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__remove_cvref) && !defined(_LIBCPP_COMPILER_GCC)
+template <class _Tp>
+using __remove_cvref_t _LIBCPP_NODEBUG = __remove_cvref(_Tp);
+#else
+template <class _Tp>
+using __remove_cvref_t _LIBCPP_NODEBUG = __remove_cv_t<__libcpp_remove_reference_t<_Tp> >;
+#endif // __has_builtin(__remove_cvref)
+
+template <class _Tp, class _Up>
+struct __is_same_uncvref : _IsSame<__remove_cvref_t<_Tp>, __remove_cvref_t<_Up> > {};
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+struct remove_cvref {
+ using type _LIBCPP_NODEBUG = __remove_cvref_t<_Tp>;
+};
+
+template <class _Tp>
+using remove_cvref_t = __remove_cvref_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_CVREF_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_extent.h b/libcxx/include/__cxx03/__type_traits/remove_extent.h
new file mode 100644
index 00000000000000..fe37b5c7266c6b
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_extent.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_EXTENT_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_EXTENT_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__remove_extent)
+template <class _Tp>
+struct remove_extent {
+ using type _LIBCPP_NODEBUG = __remove_extent(_Tp);
+};
+
+template <class _Tp>
+using __remove_extent_t = __remove_extent(_Tp);
+#else
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_extent {
+ typedef _Tp type;
+};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_extent<_Tp[]> {
+ typedef _Tp type;
+};
+template <class _Tp, size_t _Np>
+struct _LIBCPP_TEMPLATE_VIS remove_extent<_Tp[_Np]> {
+ typedef _Tp type;
+};
+
+template <class _Tp>
+using __remove_extent_t = typename remove_extent<_Tp>::type;
+#endif // __has_builtin(__remove_extent)
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using remove_extent_t = __remove_extent_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_EXTENT_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_pointer.h b/libcxx/include/__cxx03/__type_traits/remove_pointer.h
new file mode 100644
index 00000000000000..1048f67055a287
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_pointer.h
@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_POINTER_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_POINTER_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if !defined(_LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS) && __has_builtin(__remove_pointer)
+template <class _Tp>
+struct remove_pointer {
+ using type _LIBCPP_NODEBUG = __remove_pointer(_Tp);
+};
+
+# ifdef _LIBCPP_COMPILER_GCC
+template <class _Tp>
+using __remove_pointer_t = typename remove_pointer<_Tp>::type;
+# else
+template <class _Tp>
+using __remove_pointer_t = __remove_pointer(_Tp);
+# endif
+#else
+// clang-format off
+template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer {typedef _LIBCPP_NODEBUG _Tp type;};
+template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp*> {typedef _LIBCPP_NODEBUG _Tp type;};
+template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp* const> {typedef _LIBCPP_NODEBUG _Tp type;};
+template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp* volatile> {typedef _LIBCPP_NODEBUG _Tp type;};
+template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp* const volatile> {typedef _LIBCPP_NODEBUG _Tp type;};
+// clang-format on
+
+template <class _Tp>
+using __remove_pointer_t = typename remove_pointer<_Tp>::type;
+#endif // !defined(_LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS) && __has_builtin(__remove_pointer)
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using remove_pointer_t = __remove_pointer_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_POINTER_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_reference.h b/libcxx/include/__cxx03/__type_traits/remove_reference.h
new file mode 100644
index 00000000000000..ba67891758adce
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_reference.h
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_REFERENCE_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_REFERENCE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__remove_reference_t)
+template <class _Tp>
+struct remove_reference {
+ using type _LIBCPP_NODEBUG = __remove_reference_t(_Tp);
+};
+
+template <class _Tp>
+using __libcpp_remove_reference_t = __remove_reference_t(_Tp);
+#elif __has_builtin(__remove_reference)
+template <class _Tp>
+struct remove_reference {
+ using type _LIBCPP_NODEBUG = __remove_reference(_Tp);
+};
+
+template <class _Tp>
+using __libcpp_remove_reference_t = typename remove_reference<_Tp>::type;
+#else
+# error "remove_reference not implemented!"
+#endif // __has_builtin(__remove_reference_t)
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using remove_reference_t = __libcpp_remove_reference_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_REFERENCE_H
diff --git a/libcxx/include/__cxx03/__type_traits/remove_volatile.h b/libcxx/include/__cxx03/__type_traits/remove_volatile.h
new file mode 100644
index 00000000000000..7600ae0ec5167e
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/remove_volatile.h
@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_REMOVE_VOLATILE_H
+#define _LIBCPP___TYPE_TRAITS_REMOVE_VOLATILE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if __has_builtin(__remove_volatile)
+template <class _Tp>
+struct remove_volatile {
+ using type _LIBCPP_NODEBUG = __remove_volatile(_Tp);
+};
+
+template <class _Tp>
+using __remove_volatile_t = __remove_volatile(_Tp);
+#else
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_volatile {
+ typedef _Tp type;
+};
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS remove_volatile<volatile _Tp> {
+ typedef _Tp type;
+};
+
+template <class _Tp>
+using __remove_volatile_t = typename remove_volatile<_Tp>::type;
+#endif // __has_builtin(__remove_volatile)
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using remove_volatile_t = __remove_volatile_t<_Tp>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_REMOVE_VOLATILE_H
diff --git a/libcxx/include/__cxx03/__type_traits/result_of.h b/libcxx/include/__cxx03/__type_traits/result_of.h
new file mode 100644
index 00000000000000..f00fa8e9be7f73
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/result_of.h
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_RESULT_OF_H
+#define _LIBCPP___TYPE_TRAITS_RESULT_OF_H
+
+#include <__config>
+#include <__functional/invoke.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// result_of
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_TYPE_TRAITS)
+template <class _Callable>
+class _LIBCPP_DEPRECATED_IN_CXX17 result_of;
+
+template <class _Fp, class... _Args>
+class _LIBCPP_TEMPLATE_VIS result_of<_Fp(_Args...)> : public __invoke_of<_Fp, _Args...> {};
+
+# if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using result_of_t _LIBCPP_DEPRECATED_IN_CXX17 = typename result_of<_Tp>::type;
+# endif // _LIBCPP_STD_VER >= 14
+#endif // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_TYPE_TRAITS)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_RESULT_OF_H
diff --git a/libcxx/include/__cxx03/__type_traits/strip_signature.h b/libcxx/include/__cxx03/__type_traits/strip_signature.h
new file mode 100644
index 00000000000000..3fe79592f55b8d
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/strip_signature.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_STRIP_SIGNATURE_H
+#define _LIBCPP___TYPE_TRAITS_STRIP_SIGNATURE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Fp>
+struct __strip_signature;
+
+# if defined(__cpp_static_call_operator) && __cpp_static_call_operator >= 202207L
+
+template <class _Rp, class... _Args>
+struct __strip_signature<_Rp (*)(_Args...)> {
+ using type = _Rp(_Args...);
+};
+
+template <class _Rp, class... _Args>
+struct __strip_signature<_Rp (*)(_Args...) noexcept> {
+ using type = _Rp(_Args...);
+};
+
+# endif // defined(__cpp_static_call_operator) && __cpp_static_call_operator >= 202207L
+
+// clang-format off
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...)> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) const> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) volatile> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) const volatile> { using type = _Rp(_Ap...); };
+
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) &> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) const &> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) volatile &> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) const volatile &> { using type = _Rp(_Ap...); };
+
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) noexcept> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) const noexcept> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) volatile noexcept> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) const volatile noexcept> { using type = _Rp(_Ap...); };
+
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) & noexcept> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) const & noexcept> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) volatile & noexcept> { using type = _Rp(_Ap...); };
+template<class _Rp, class _Gp, class ..._Ap>
+struct __strip_signature<_Rp (_Gp::*) (_Ap...) const volatile & noexcept> { using type = _Rp(_Ap...); };
+// clang-format on
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___TYPE_TRAITS_STRIP_SIGNATURE_H
diff --git a/libcxx/include/__cxx03/__type_traits/type_identity.h b/libcxx/include/__cxx03/__type_traits/type_identity.h
new file mode 100644
index 00000000000000..b0b5a1277d5962
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/type_identity.h
@@ -0,0 +1,39 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_TYPE_IDENTITY_H
+#define _LIBCPP___TYPE_TRAITS_TYPE_IDENTITY_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __type_identity {
+ typedef _Tp type;
+};
+
+template <class _Tp>
+using __type_identity_t _LIBCPP_NODEBUG = typename __type_identity<_Tp>::type;
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+struct type_identity {
+ typedef _Tp type;
+};
+template <class _Tp>
+using type_identity_t = typename type_identity<_Tp>::type;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_TYPE_IDENTITY_H
diff --git a/libcxx/include/__cxx03/__type_traits/type_list.h b/libcxx/include/__cxx03/__type_traits/type_list.h
new file mode 100644
index 00000000000000..02905707ee37a2
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/type_list.h
@@ -0,0 +1,42 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_TYPE_LIST_H
+#define _LIBCPP___TYPE_TRAITS_TYPE_LIST_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Hp, class _Tp>
+struct __type_list {
+ typedef _Hp _Head;
+ typedef _Tp _Tail;
+};
+
+template <class _TypeList, size_t _Size, bool = _Size <= sizeof(typename _TypeList::_Head)>
+struct __find_first;
+
+template <class _Hp, class _Tp, size_t _Size>
+struct __find_first<__type_list<_Hp, _Tp>, _Size, true> {
+ typedef _LIBCPP_NODEBUG _Hp type;
+};
+
+template <class _Hp, class _Tp, size_t _Size>
+struct __find_first<__type_list<_Hp, _Tp>, _Size, false> {
+ typedef _LIBCPP_NODEBUG typename __find_first<_Tp, _Size>::type type;
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_TYPE_LIST_H
diff --git a/libcxx/include/__cxx03/__type_traits/underlying_type.h b/libcxx/include/__cxx03/__type_traits/underlying_type.h
new file mode 100644
index 00000000000000..16e7501dee17df
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/underlying_type.h
@@ -0,0 +1,42 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_UNDERLYING_TYPE_H
+#define _LIBCPP___TYPE_TRAITS_UNDERLYING_TYPE_H
+
+#include <__config>
+#include <__type_traits/is_enum.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, bool = is_enum<_Tp>::value>
+struct __underlying_type_impl;
+
+template <class _Tp>
+struct __underlying_type_impl<_Tp, false> {};
+
+template <class _Tp>
+struct __underlying_type_impl<_Tp, true> {
+ typedef __underlying_type(_Tp) type;
+};
+
+template <class _Tp>
+struct underlying_type : __underlying_type_impl<_Tp, is_enum<_Tp>::value> {};
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp>
+using underlying_type_t = typename underlying_type<_Tp>::type;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_UNDERLYING_TYPE_H
diff --git a/libcxx/include/__cxx03/__type_traits/unwrap_ref.h b/libcxx/include/__cxx03/__type_traits/unwrap_ref.h
new file mode 100644
index 00000000000000..6bd74550f30921
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/unwrap_ref.h
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_UNWRAP_REF_H
+#define _LIBCPP___TYPE_TRAITS_UNWRAP_REF_H
+
+#include <__config>
+#include <__fwd/functional.h>
+#include <__type_traits/decay.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct __unwrap_reference {
+ typedef _LIBCPP_NODEBUG _Tp type;
+};
+
+template <class _Tp>
+struct __unwrap_reference<reference_wrapper<_Tp> > {
+ typedef _LIBCPP_NODEBUG _Tp& type;
+};
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp>
+struct unwrap_reference : __unwrap_reference<_Tp> {};
+
+template <class _Tp>
+using unwrap_reference_t = typename unwrap_reference<_Tp>::type;
+
+template <class _Tp>
+struct unwrap_ref_decay : unwrap_reference<__decay_t<_Tp> > {};
+
+template <class _Tp>
+using unwrap_ref_decay_t = typename unwrap_ref_decay<_Tp>::type;
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+struct __unwrap_ref_decay
+#if _LIBCPP_STD_VER >= 20
+ : unwrap_ref_decay<_Tp>
+#else
+ : __unwrap_reference<__decay_t<_Tp> >
+#endif
+{
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_UNWRAP_REF_H
diff --git a/libcxx/include/__cxx03/__type_traits/void_t.h b/libcxx/include/__cxx03/__type_traits/void_t.h
new file mode 100644
index 00000000000000..985bba02e72f77
--- /dev/null
+++ b/libcxx/include/__cxx03/__type_traits/void_t.h
@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_VOID_T_H
+#define _LIBCPP___TYPE_TRAITS_VOID_T_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+template <class...>
+using void_t = void;
+#endif
+
+template <class...>
+using __void_t = void;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_VOID_T_H
diff --git a/libcxx/include/__cxx03/__undef_macros b/libcxx/include/__cxx03/__undef_macros
new file mode 100644
index 00000000000000..29ab327e1c375a
--- /dev/null
+++ b/libcxx/include/__cxx03/__undef_macros
@@ -0,0 +1,28 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifdef min
+# undef min
+#endif
+
+#ifdef max
+# undef max
+#endif
+
+#ifdef refresh
+# undef refresh
+#endif
+
+#ifdef move
+# undef move
+#endif
+
+#ifdef erase
+# undef erase
+#endif
diff --git a/libcxx/include/__cxx03/__utility/as_const.h b/libcxx/include/__cxx03/__utility/as_const.h
new file mode 100644
index 00000000000000..582dd42f407915
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/as_const.h
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_AS_CONST_H
+#define _LIBCPP___UTILITY_AS_CONST_H
+
+#include <__config>
+#include <__type_traits/add_const.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr add_const_t<_Tp>& as_const(_Tp& __t) noexcept {
+ return __t;
+}
+
+template <class _Tp>
+void as_const(const _Tp&&) = delete;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_AS_CONST_H
diff --git a/libcxx/include/__cxx03/__utility/as_lvalue.h b/libcxx/include/__cxx03/__utility/as_lvalue.h
new file mode 100644
index 00000000000000..159f45dad4d41c
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/as_lvalue.h
@@ -0,0 +1,37 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_AS_LVALUE_H
+#define _LIBCPP___UTILITY_AS_LVALUE_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Tp& __as_lvalue(_LIBCPP_LIFETIMEBOUND _Tp&& __t) {
+ return static_cast<_Tp&>(__t);
+}
+
+#endif // !_LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___UTILITY_AS_LVALUE_H
diff --git a/libcxx/include/__cxx03/__utility/auto_cast.h b/libcxx/include/__cxx03/__utility/auto_cast.h
new file mode 100644
index 00000000000000..06715b3438f996
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/auto_cast.h
@@ -0,0 +1,22 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_AUTO_CAST_H
+#define _LIBCPP___UTILITY_AUTO_CAST_H
+
+#include <__config>
+#include <__type_traits/decay.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#define _LIBCPP_AUTO_CAST(expr) static_cast<::std::__decay_t<decltype((expr))> >(expr)
+
+#endif // _LIBCPP___UTILITY_AUTO_CAST_H
diff --git a/libcxx/include/__cxx03/__utility/cmp.h b/libcxx/include/__cxx03/__utility/cmp.h
new file mode 100644
index 00000000000000..b7c1ed614dfcb6
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/cmp.h
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_CMP_H
+#define _LIBCPP___UTILITY_CMP_H
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/make_unsigned.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_integer _Tp, __libcpp_integer _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool cmp_equal(_Tp __t, _Up __u) noexcept {
+ if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>)
+ return __t == __u;
+ else if constexpr (is_signed_v<_Tp>)
+ return __t < 0 ? false : make_unsigned_t<_Tp>(__t) == __u;
+ else
+ return __u < 0 ? false : __t == make_unsigned_t<_Up>(__u);
+}
+
+template <__libcpp_integer _Tp, __libcpp_integer _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool cmp_not_equal(_Tp __t, _Up __u) noexcept {
+ return !std::cmp_equal(__t, __u);
+}
+
+template <__libcpp_integer _Tp, __libcpp_integer _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool cmp_less(_Tp __t, _Up __u) noexcept {
+ if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>)
+ return __t < __u;
+ else if constexpr (is_signed_v<_Tp>)
+ return __t < 0 ? true : make_unsigned_t<_Tp>(__t) < __u;
+ else
+ return __u < 0 ? false : __t < make_unsigned_t<_Up>(__u);
+}
+
+template <__libcpp_integer _Tp, __libcpp_integer _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool cmp_greater(_Tp __t, _Up __u) noexcept {
+ return std::cmp_less(__u, __t);
+}
+
+template <__libcpp_integer _Tp, __libcpp_integer _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool cmp_less_equal(_Tp __t, _Up __u) noexcept {
+ return !std::cmp_greater(__t, __u);
+}
+
+template <__libcpp_integer _Tp, __libcpp_integer _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool cmp_greater_equal(_Tp __t, _Up __u) noexcept {
+ return !std::cmp_less(__t, __u);
+}
+
+template <__libcpp_integer _Tp, __libcpp_integer _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool in_range(_Up __u) noexcept {
+ return std::cmp_less_equal(__u, numeric_limits<_Tp>::max()) &&
+ std::cmp_greater_equal(__u, numeric_limits<_Tp>::min());
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___UTILITY_CMP_H
diff --git a/libcxx/include/__cxx03/__utility/convert_to_integral.h b/libcxx/include/__cxx03/__utility/convert_to_integral.h
new file mode 100644
index 00000000000000..f1fcdd98010cca
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/convert_to_integral.h
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_CONVERT_TO_INTEGRAL_H
+#define _LIBCPP___UTILITY_CONVERT_TO_INTEGRAL_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_enum.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/underlying_type.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __convert_to_integral(int __val) { return __val; }
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unsigned __convert_to_integral(unsigned __val) { return __val; }
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR long __convert_to_integral(long __val) { return __val; }
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unsigned long __convert_to_integral(unsigned long __val) {
+ return __val;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR long long __convert_to_integral(long long __val) { return __val; }
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR unsigned long long __convert_to_integral(unsigned long long __val) {
+ return __val;
+}
+
+template <typename _Fp, __enable_if_t<is_floating_point<_Fp>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR long long __convert_to_integral(_Fp __val) {
+ return __val;
+}
+
+#ifndef _LIBCPP_HAS_NO_INT128
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __int128_t __convert_to_integral(__int128_t __val) { return __val; }
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __uint128_t __convert_to_integral(__uint128_t __val) { return __val; }
+#endif
+
+template <class _Tp, bool = is_enum<_Tp>::value>
+struct __sfinae_underlying_type {
+ typedef typename underlying_type<_Tp>::type type;
+ typedef decltype(((type)1) + 0) __promoted_type;
+};
+
+template <class _Tp>
+struct __sfinae_underlying_type<_Tp, false> {};
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR typename __sfinae_underlying_type<_Tp>::__promoted_type
+__convert_to_integral(_Tp __val) {
+ return __val;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_CONVERT_TO_INTEGRAL_H
diff --git a/libcxx/include/__cxx03/__utility/declval.h b/libcxx/include/__cxx03/__utility/declval.h
new file mode 100644
index 00000000000000..d0856b8afa4db9
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/declval.h
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_DECLVAL_H
+#define _LIBCPP___UTILITY_DECLVAL_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Suppress deprecation notice for volatile-qualified return type resulting
+// from volatile-qualified types _Tp.
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Tp>
+_Tp&& __declval(int);
+template <class _Tp>
+_Tp __declval(long);
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI decltype(std::__declval<_Tp>(0)) declval() _NOEXCEPT {
+ static_assert(!__is_same(_Tp, _Tp),
+ "std::declval can only be used in an unevaluated context. "
+ "It's likely that your current usage is trying to extract a value from the function.");
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_DECLVAL_H
diff --git a/libcxx/include/__cxx03/__utility/empty.h b/libcxx/include/__cxx03/__utility/empty.h
new file mode 100644
index 00000000000000..8cca197145c723
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/empty.h
@@ -0,0 +1,24 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_EMPTY_H
+#define _LIBCPP___UTILITY_EMPTY_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __empty {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_EMPTY_H
diff --git a/libcxx/include/__cxx03/__utility/exception_guard.h b/libcxx/include/__cxx03/__utility/exception_guard.h
new file mode 100644
index 00000000000000..9f732ca265c86e
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/exception_guard.h
@@ -0,0 +1,144 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_TRANSACTION_H
+#define _LIBCPP___UTILITY_TRANSACTION_H
+
+#include <__assert>
+#include <__config>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__utility/exchange.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// __exception_guard is a helper class for writing code with the strong exception guarantee.
+//
+// When writing code that can throw an exception, one can store rollback instructions in an
+// exception guard so that if an exception is thrown at any point during the lifetime of the
+// exception guard, it will be rolled back automatically. When the exception guard is done, one
+// must mark it as being complete so it isn't rolled back when the exception guard is destroyed.
+//
+// Exception guards are not default constructible, they can't be copied or assigned to, but
+// they can be moved around for convenience.
+//
+// __exception_guard is a no-op in -fno-exceptions mode to produce better code-gen. This means
+// that we don't provide the strong exception guarantees. However, Clang doesn't generate cleanup
+// code with exceptions disabled, so even if we wanted to provide the strong exception guarantees
+// we couldn't. This is also only relevant for constructs with a stack of
+// -fexceptions > -fno-exceptions > -fexceptions code, since the exception can't be caught where
+// exceptions are disabled. While -fexceptions > -fno-exceptions is quite common
+// (e.g. libc++.dylib > -fno-exceptions), having another layer with exceptions enabled seems a lot
+// less common, especially one that tries to catch an exception through -fno-exceptions code.
+//
+// __exception_guard can help greatly simplify code that would normally be cluttered by
+// `#if _LIBCPP_HAS_NO_EXCEPTIONS`. For example:
+//
+// template <class Iterator, class Size, class OutputIterator>
+// Iterator uninitialized_copy_n(Iterator iter, Size n, OutputIterator out) {
+// typedef typename iterator_traits<Iterator>::value_type value_type;
+// __exception_guard guard([start=out, &out] {
+// std::destroy(start, out);
+// });
+//
+// for (; n > 0; ++iter, ++out, --n) {
+// ::new ((void*)std::addressof(*out)) value_type(*iter);
+// }
+// guard.__complete();
+// return out;
+// }
+//
+
+template <class _Rollback>
+struct __exception_guard_exceptions {
+ __exception_guard_exceptions() = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit __exception_guard_exceptions(_Rollback __rollback)
+ : __rollback_(std::move(__rollback)), __completed_(false) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ __exception_guard_exceptions(__exception_guard_exceptions&& __other)
+ _NOEXCEPT_(is_nothrow_move_constructible<_Rollback>::value)
+ : __rollback_(std::move(__other.__rollback_)), __completed_(__other.__completed_) {
+ __other.__completed_ = true;
+ }
+
+ __exception_guard_exceptions(__exception_guard_exceptions const&) = delete;
+ __exception_guard_exceptions& operator=(__exception_guard_exceptions const&) = delete;
+ __exception_guard_exceptions& operator=(__exception_guard_exceptions&&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __complete() _NOEXCEPT { __completed_ = true; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__exception_guard_exceptions() {
+ if (!__completed_)
+ __rollback_();
+ }
+
+private:
+ _Rollback __rollback_;
+ bool __completed_;
+};
+
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(__exception_guard_exceptions);
+
+template <class _Rollback>
+struct __exception_guard_noexceptions {
+ __exception_guard_noexceptions() = delete;
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NODEBUG explicit __exception_guard_noexceptions(_Rollback) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NODEBUG
+ __exception_guard_noexceptions(__exception_guard_noexceptions&& __other)
+ _NOEXCEPT_(is_nothrow_move_constructible<_Rollback>::value)
+ : __completed_(__other.__completed_) {
+ __other.__completed_ = true;
+ }
+
+ __exception_guard_noexceptions(__exception_guard_noexceptions const&) = delete;
+ __exception_guard_noexceptions& operator=(__exception_guard_noexceptions const&) = delete;
+ __exception_guard_noexceptions& operator=(__exception_guard_noexceptions&&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NODEBUG void __complete() _NOEXCEPT {
+ __completed_ = true;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NODEBUG ~__exception_guard_noexceptions() {
+ _LIBCPP_ASSERT_INTERNAL(__completed_, "__exception_guard not completed with exceptions disabled");
+ }
+
+private:
+ bool __completed_ = false;
+};
+
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(__exception_guard_noexceptions);
+
+#ifdef _LIBCPP_HAS_NO_EXCEPTIONS
+template <class _Rollback>
+using __exception_guard = __exception_guard_noexceptions<_Rollback>;
+#else
+template <class _Rollback>
+using __exception_guard = __exception_guard_exceptions<_Rollback>;
+#endif
+
+template <class _Rollback>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __exception_guard<_Rollback> __make_exception_guard(_Rollback __rollback) {
+ return __exception_guard<_Rollback>(std::move(__rollback));
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___UTILITY_TRANSACTION_H
diff --git a/libcxx/include/__cxx03/__utility/exchange.h b/libcxx/include/__cxx03/__utility/exchange.h
new file mode 100644
index 00000000000000..957e9d0acaa65e
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/exchange.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_EXCHANGE_H
+#define _LIBCPP___UTILITY_EXCHANGE_H
+
+#include <__config>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 14
+template <class _T1, class _T2 = _T1>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _T1 exchange(_T1& __obj, _T2&& __new_value) noexcept(
+ is_nothrow_move_constructible<_T1>::value && is_nothrow_assignable<_T1&, _T2>::value) {
+ _T1 __old_value = std::move(__obj);
+ __obj = std::forward<_T2>(__new_value);
+ return __old_value;
+}
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___UTILITY_EXCHANGE_H
diff --git a/libcxx/include/__cxx03/__utility/forward.h b/libcxx/include/__cxx03/__utility/forward.h
new file mode 100644
index 00000000000000..d5275dcbd0edc2
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/forward.h
@@ -0,0 +1,38 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_FORWARD_H
+#define _LIBCPP___UTILITY_FORWARD_H
+
+#include <__config>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp&&
+forward(_LIBCPP_LIFETIMEBOUND __libcpp_remove_reference_t<_Tp>& __t) _NOEXCEPT {
+ return static_cast<_Tp&&>(__t);
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp&&
+forward(_LIBCPP_LIFETIMEBOUND __libcpp_remove_reference_t<_Tp>&& __t) _NOEXCEPT {
+ static_assert(!is_lvalue_reference<_Tp>::value, "cannot forward an rvalue as an lvalue");
+ return static_cast<_Tp&&>(__t);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_FORWARD_H
diff --git a/libcxx/include/__cxx03/__utility/forward_like.h b/libcxx/include/__cxx03/__utility/forward_like.h
new file mode 100644
index 00000000000000..0206ce23a56681
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/forward_like.h
@@ -0,0 +1,46 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_FORWARD_LIKE_H
+#define _LIBCPP___UTILITY_FORWARD_LIKE_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 23
+
+template <class _Ap, class _Bp>
+using _CopyConst = _If<is_const_v<_Ap>, const _Bp, _Bp>;
+
+template <class _Ap, class _Bp>
+using _OverrideRef = _If<is_rvalue_reference_v<_Ap>, remove_reference_t<_Bp>&&, _Bp&>;
+
+template <class _Ap, class _Bp>
+using _ForwardLike = _OverrideRef<_Ap&&, _CopyConst<remove_reference_t<_Ap>, remove_reference_t<_Bp>>>;
+
+template <class _Tp, class _Up>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto
+forward_like(_LIBCPP_LIFETIMEBOUND _Up&& __ux) noexcept -> _ForwardLike<_Tp, _Up> {
+ return static_cast<_ForwardLike<_Tp, _Up>>(__ux);
+}
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_FORWARD_LIKE_H
diff --git a/libcxx/include/__cxx03/__utility/in_place.h b/libcxx/include/__cxx03/__utility/in_place.h
new file mode 100644
index 00000000000000..fa7a2f4bfd4a95
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/in_place.h
@@ -0,0 +1,63 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_IN_PLACE_H
+#define _LIBCPP___UTILITY_IN_PLACE_H
+
+#include <__config>
+#include <__type_traits/remove_cvref.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+struct _LIBCPP_EXPORTED_FROM_ABI in_place_t {
+ explicit in_place_t() = default;
+};
+inline constexpr in_place_t in_place{};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS in_place_type_t {
+ _LIBCPP_HIDE_FROM_ABI explicit in_place_type_t() = default;
+};
+template <class _Tp>
+inline constexpr in_place_type_t<_Tp> in_place_type{};
+
+template <size_t _Idx>
+struct _LIBCPP_TEMPLATE_VIS in_place_index_t {
+ _LIBCPP_HIDE_FROM_ABI explicit in_place_index_t() = default;
+};
+template <size_t _Idx>
+inline constexpr in_place_index_t<_Idx> in_place_index{};
+
+template <class _Tp>
+struct __is_inplace_type_imp : false_type {};
+template <class _Tp>
+struct __is_inplace_type_imp<in_place_type_t<_Tp>> : true_type {};
+
+template <class _Tp>
+using __is_inplace_type = __is_inplace_type_imp<__remove_cvref_t<_Tp>>;
+
+template <class _Tp>
+struct __is_inplace_index_imp : false_type {};
+template <size_t _Idx>
+struct __is_inplace_index_imp<in_place_index_t<_Idx>> : true_type {};
+
+template <class _Tp>
+using __is_inplace_index = __is_inplace_index_imp<__remove_cvref_t<_Tp>>;
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_IN_PLACE_H
diff --git a/libcxx/include/__cxx03/__utility/integer_sequence.h b/libcxx/include/__cxx03/__utility/integer_sequence.h
new file mode 100644
index 00000000000000..ccce9433e7a801
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/integer_sequence.h
@@ -0,0 +1,90 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_INTEGER_SEQUENCE_H
+#define _LIBCPP___UTILITY_INTEGER_SEQUENCE_H
+
+#include <__config>
+#include <__type_traits/is_integral.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t...>
+struct __tuple_indices;
+
+template <class _IdxType, _IdxType... _Values>
+struct __integer_sequence {
+ template <template <class _OIdxType, _OIdxType...> class _ToIndexSeq, class _ToIndexType>
+ using __convert = _ToIndexSeq<_ToIndexType, _Values...>;
+
+ template <size_t _Sp>
+ using __to_tuple_indices = __tuple_indices<(_Values + _Sp)...>;
+};
+
+#if __has_builtin(__make_integer_seq)
+template <size_t _Ep, size_t _Sp>
+using __make_indices_imp =
+ typename __make_integer_seq<__integer_sequence, size_t, _Ep - _Sp>::template __to_tuple_indices<_Sp>;
+#elif __has_builtin(__integer_pack)
+template <size_t _Ep, size_t _Sp>
+using __make_indices_imp =
+ typename __integer_sequence<size_t, __integer_pack(_Ep - _Sp)...>::template __to_tuple_indices<_Sp>;
+#else
+# error "No known way to get an integer pack from the compiler"
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+
+template <class _Tp, _Tp... _Ip>
+struct _LIBCPP_TEMPLATE_VIS integer_sequence {
+ typedef _Tp value_type;
+ static_assert(is_integral<_Tp>::value, "std::integer_sequence can only be instantiated with an integral type");
+ static _LIBCPP_HIDE_FROM_ABI constexpr size_t size() noexcept { return sizeof...(_Ip); }
+};
+
+template <size_t... _Ip>
+using index_sequence = integer_sequence<size_t, _Ip...>;
+
+# if __has_builtin(__make_integer_seq)
+
+template <class _Tp, _Tp _Ep>
+using make_integer_sequence _LIBCPP_NODEBUG = __make_integer_seq<integer_sequence, _Tp, _Ep>;
+
+# elif __has_builtin(__integer_pack)
+
+template <class _Tp, _Tp _SequenceSize>
+using make_integer_sequence _LIBCPP_NODEBUG = integer_sequence<_Tp, __integer_pack(_SequenceSize)...>;
+
+# else
+# error "No known way to get an integer pack from the compiler"
+# endif
+
+template <size_t _Np>
+using make_index_sequence = make_integer_sequence<size_t, _Np>;
+
+template <class... _Tp>
+using index_sequence_for = make_index_sequence<sizeof...(_Tp)>;
+
+# if _LIBCPP_STD_VER >= 20
+// Executes __func for every element in an index_sequence.
+template <size_t... _Index, class _Function>
+_LIBCPP_HIDE_FROM_ABI constexpr void __for_each_index_sequence(index_sequence<_Index...>, _Function __func) {
+ (__func.template operator()<_Index>(), ...);
+}
+# endif // _LIBCPP_STD_VER >= 20
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_INTEGER_SEQUENCE_H
diff --git a/libcxx/include/__cxx03/__utility/is_pointer_in_range.h b/libcxx/include/__cxx03/__utility/is_pointer_in_range.h
new file mode 100644
index 00000000000000..4130b4ac707000
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/is_pointer_in_range.h
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_IS_POINTER_IN_RANGE_H
+#define _LIBCPP___UTILITY_IS_POINTER_IN_RANGE_H
+
+#include <__algorithm/comp.h>
+#include <__assert>
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <__utility/is_valid_range.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Up, class = void>
+struct __is_less_than_comparable : false_type {};
+
+template <class _Tp, class _Up>
+struct __is_less_than_comparable<_Tp, _Up, __void_t<decltype(std::declval<_Tp>() < std::declval<_Up>())> > : true_type {
+};
+
+template <class _Tp, class _Up, __enable_if_t<__is_less_than_comparable<const _Tp*, const _Up*>::value, int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_SANITIZE("address") bool
+__is_pointer_in_range(const _Tp* __begin, const _Tp* __end, const _Up* __ptr) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__begin, __end), "[__begin, __end) is not a valid range");
+
+ if (__libcpp_is_constant_evaluated()) {
+ // If this is not a constant during constant evaluation we know that __ptr is not part of the allocation where
+ // [__begin, __end) is.
+ if (!__builtin_constant_p(__begin <= __ptr && __ptr < __end))
+ return false;
+ }
+
+ return !__less<>()(__ptr, __begin) && __less<>()(__ptr, __end);
+}
+
+template <class _Tp, class _Up, __enable_if_t<!__is_less_than_comparable<const _Tp*, const _Up*>::value, int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_SANITIZE("address") bool
+__is_pointer_in_range(const _Tp* __begin, const _Tp* __end, const _Up* __ptr) {
+ if (__libcpp_is_constant_evaluated())
+ return false;
+
+ return reinterpret_cast<const char*>(__begin) <= reinterpret_cast<const char*>(__ptr) &&
+ reinterpret_cast<const char*>(__ptr) < reinterpret_cast<const char*>(__end);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_IS_POINTER_IN_RANGE_H
diff --git a/libcxx/include/__cxx03/__utility/is_valid_range.h b/libcxx/include/__cxx03/__utility/is_valid_range.h
new file mode 100644
index 00000000000000..7286662dbf3092
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/is_valid_range.h
@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_IS_VALID_RANGE_H
+#define _LIBCPP___UTILITY_IS_VALID_RANGE_H
+
+#include <__algorithm/comp.h>
+#include <__config>
+#include <__type_traits/is_constant_evaluated.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_SANITIZE("address") bool
+__is_valid_range(const _Tp* __first, const _Tp* __last) {
+ if (__libcpp_is_constant_evaluated()) {
+ // If this is not a constant during constant evaluation, that is because __first and __last are not
+ // part of the same allocation. If they are part of the same allocation, we must still make sure they
+ // are ordered properly.
+ return __builtin_constant_p(__first <= __last) && __first <= __last;
+ }
+
+ return !__less<>()(__last, __first);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_IS_VALID_RANGE_H
diff --git a/libcxx/include/__cxx03/__utility/move.h b/libcxx/include/__cxx03/__utility/move.h
new file mode 100644
index 00000000000000..b6a42db0545e27
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/move.h
@@ -0,0 +1,49 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_MOVE_H
+#define _LIBCPP___UTILITY_MOVE_H
+
+#include <__config>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/remove_reference.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __libcpp_remove_reference_t<_Tp>&&
+move(_LIBCPP_LIFETIMEBOUND _Tp&& __t) _NOEXCEPT {
+ typedef _LIBCPP_NODEBUG __libcpp_remove_reference_t<_Tp> _Up;
+ return static_cast<_Up&&>(__t);
+}
+
+template <class _Tp>
+using __move_if_noexcept_result_t =
+ __conditional_t<!is_nothrow_move_constructible<_Tp>::value && is_copy_constructible<_Tp>::value, const _Tp&, _Tp&&>;
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __move_if_noexcept_result_t<_Tp>
+move_if_noexcept(_LIBCPP_LIFETIMEBOUND _Tp& __x) _NOEXCEPT {
+ return std::move(__x);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___UTILITY_MOVE_H
diff --git a/libcxx/include/__cxx03/__utility/no_destroy.h b/libcxx/include/__cxx03/__utility/no_destroy.h
new file mode 100644
index 00000000000000..8edd194577d7c7
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/no_destroy.h
@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_NO_DESTROY_H
+#define _LIBCPP___UTILITY_NO_DESTROY_H
+
+#include <__config>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__utility/forward.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __uninitialized_tag {};
+
+// This class stores an object of type _Tp but never destroys it.
+//
+// This is akin to using __attribute__((no_destroy)), except that it is possible
+// to control the lifetime of the object with more flexibility by deciding e.g.
+// whether to initialize the object at construction or to defer to a later
+// initialization using __emplace.
+template <class _Tp>
+struct __no_destroy {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __no_destroy(__uninitialized_tag) : __obj_() {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI explicit __no_destroy(_Args&&... __args) {
+ ::new ((void*)__obj_) _Tp(std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _Tp& __emplace(_Args&&... __args) {
+ return *(::new ((void*)__obj_) _Tp(std::forward<_Args>(__args)...));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _Tp& __get() { return *reinterpret_cast<_Tp*>(__obj_); }
+ _LIBCPP_HIDE_FROM_ABI _Tp const& __get() const { return *reinterpret_cast<const _Tp*>(__obj_); }
+
+private:
+ _ALIGNAS_TYPE(_Tp) char __obj_[sizeof(_Tp)];
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_NO_DESTROY_H
diff --git a/libcxx/include/__cxx03/__utility/pair.h b/libcxx/include/__cxx03/__utility/pair.h
new file mode 100644
index 00000000000000..c0002b7abb3ca4
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/pair.h
@@ -0,0 +1,718 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_PAIR_H
+#define _LIBCPP___UTILITY_PAIR_H
+
+#include <__compare/common_comparison_category.h>
+#include <__compare/synth_three_way.h>
+#include <__concepts/different_from.h>
+#include <__config>
+#include <__fwd/array.h>
+#include <__fwd/pair.h>
+#include <__fwd/tuple.h>
+#include <__tuple/sfinae_helpers.h>
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_indices.h>
+#include <__tuple/tuple_like_no_subrange.h>
+#include <__tuple/tuple_size.h>
+#include <__type_traits/common_reference.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_implicitly_default_constructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/nat.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/unwrap_ref.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/piecewise_construct.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class, class>
+struct __non_trivially_copyable_base {
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI __non_trivially_copyable_base() _NOEXCEPT {}
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+ __non_trivially_copyable_base(__non_trivially_copyable_base const&) _NOEXCEPT {}
+};
+
+template <class _T1, class _T2>
+struct _LIBCPP_TEMPLATE_VIS pair
+#if defined(_LIBCPP_DEPRECATED_ABI_DISABLE_PAIR_TRIVIAL_COPY_CTOR)
+ : private __non_trivially_copyable_base<_T1, _T2>
+#endif
+{
+ using first_type = _T1;
+ using second_type = _T2;
+
+ _T1 first;
+ _T2 second;
+
+ using __trivially_relocatable =
+ __conditional_t<__libcpp_is_trivially_relocatable<_T1>::value && __libcpp_is_trivially_relocatable<_T2>::value,
+ pair,
+ void>;
+
+ _LIBCPP_HIDE_FROM_ABI pair(pair const&) = default;
+ _LIBCPP_HIDE_FROM_ABI pair(pair&&) = default;
+
+ // When we are requested for pair to be trivially copyable by the ABI macro, we use defaulted members
+ // if it is both legal to do it (i.e. no references) and we have a way to actually implement it, which requires
+ // the __enable_if__ attribute before C++20.
+#ifdef _LIBCPP_ABI_TRIVIALLY_COPYABLE_PAIR
+ // FIXME: This should really just be a static constexpr variable. It's in a struct to avoid gdb printing the value
+ // when printing a pair
+ struct __has_defaulted_members {
+ static const bool value = !is_reference<first_type>::value && !is_reference<second_type>::value;
+ };
+# if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr pair& operator=(const pair&)
+ requires __has_defaulted_members::value
+ = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr pair& operator=(pair&&)
+ requires __has_defaulted_members::value
+ = default;
+# elif __has_attribute(__enable_if__)
+ _LIBCPP_HIDE_FROM_ABI pair& operator=(const pair&)
+ __attribute__((__enable_if__(__has_defaulted_members::value, ""))) = default;
+
+ _LIBCPP_HIDE_FROM_ABI pair& operator=(pair&&)
+ __attribute__((__enable_if__(__has_defaulted_members::value, ""))) = default;
+# else
+# error "_LIBCPP_ABI_TRIVIALLY_COPYABLE_PAIR isn't supported with this compiler"
+# endif
+#else
+ struct __has_defaulted_members {
+ static const bool value = false;
+ };
+#endif // defined(_LIBCPP_ABI_TRIVIALLY_COPYABLE_PAIR) && __has_attribute(__enable_if__)
+
+#ifdef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI pair() : first(), second() {}
+
+ _LIBCPP_HIDE_FROM_ABI pair(_T1 const& __t1, _T2 const& __t2) : first(__t1), second(__t2) {}
+
+ template <class _U1, class _U2>
+ _LIBCPP_HIDE_FROM_ABI pair(const pair<_U1, _U2>& __p) : first(__p.first), second(__p.second) {}
+
+ _LIBCPP_HIDE_FROM_ABI pair& operator=(pair const& __p) {
+ first = __p.first;
+ second = __p.second;
+ return *this;
+ }
+
+ // Extension: This is provided in C++03 because it allows properly handling the
+ // assignment to a pair containing references, which would be a hard
+ // error otherwise.
+ template <
+ class _U1,
+ class _U2,
+ __enable_if_t<is_assignable<first_type&, _U1 const&>::value && is_assignable<second_type&, _U2 const&>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair& operator=(pair<_U1, _U2> const& __p) {
+ first = __p.first;
+ second = __p.second;
+ return *this;
+ }
+#else
+ struct _CheckArgs {
+ template <int&...>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __enable_implicit_default() {
+ return __is_implicitly_default_constructible<_T1>::value && __is_implicitly_default_constructible<_T2>::value;
+ }
+
+ template <int&...>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __enable_default() {
+ return is_default_constructible<_T1>::value && is_default_constructible<_T2>::value;
+ }
+
+ template <class _U1, class _U2>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __is_pair_constructible() {
+ return is_constructible<first_type, _U1>::value && is_constructible<second_type, _U2>::value;
+ }
+
+ template <class _U1, class _U2>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __is_implicit() {
+ return is_convertible<_U1, first_type>::value && is_convertible<_U2, second_type>::value;
+ }
+ };
+
+ template <bool _MaybeEnable>
+ using _CheckArgsDep _LIBCPP_NODEBUG =
+ typename conditional< _MaybeEnable, _CheckArgs, __check_tuple_constructor_fail>::type;
+
+ template <bool _Dummy = true, __enable_if_t<_CheckArgsDep<_Dummy>::__enable_default(), int> = 0>
+ explicit(!_CheckArgsDep<_Dummy>::__enable_implicit_default()) _LIBCPP_HIDE_FROM_ABI constexpr pair() noexcept(
+ is_nothrow_default_constructible<first_type>::value && is_nothrow_default_constructible<second_type>::value)
+ : first(), second() {}
+
+ template <bool _Dummy = true,
+ __enable_if_t<_CheckArgsDep<_Dummy>::template __is_pair_constructible<_T1 const&, _T2 const&>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(!_CheckArgsDep<_Dummy>::template __is_implicit<_T1 const&, _T2 const&>())
+ pair(_T1 const& __t1, _T2 const& __t2) noexcept(is_nothrow_copy_constructible<first_type>::value &&
+ is_nothrow_copy_constructible<second_type>::value)
+ : first(__t1), second(__t2) {}
+
+ template <
+# if _LIBCPP_STD_VER >= 23 // http://wg21.link/P1951
+ class _U1 = _T1,
+ class _U2 = _T2,
+# else
+ class _U1,
+ class _U2,
+# endif
+ __enable_if_t<_CheckArgs::template __is_pair_constructible<_U1, _U2>(), int> = 0 >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(!_CheckArgs::template __is_implicit<_U1, _U2>())
+ pair(_U1&& __u1, _U2&& __u2) noexcept(is_nothrow_constructible<first_type, _U1>::value &&
+ is_nothrow_constructible<second_type, _U2>::value)
+ : first(std::forward<_U1>(__u1)), second(std::forward<_U2>(__u2)) {
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ template <class _U1, class _U2, __enable_if_t<_CheckArgs::template __is_pair_constructible<_U1&, _U2&>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_CheckArgs::template __is_implicit<_U1&, _U2&>())
+ pair(pair<_U1, _U2>& __p) noexcept((is_nothrow_constructible<first_type, _U1&>::value &&
+ is_nothrow_constructible<second_type, _U2&>::value))
+ : first(__p.first), second(__p.second) {}
+# endif
+
+ template <class _U1,
+ class _U2,
+ __enable_if_t<_CheckArgs::template __is_pair_constructible<_U1 const&, _U2 const&>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(!_CheckArgs::template __is_implicit<_U1 const&, _U2 const&>())
+ pair(pair<_U1, _U2> const& __p) noexcept(is_nothrow_constructible<first_type, _U1 const&>::value &&
+ is_nothrow_constructible<second_type, _U2 const&>::value)
+ : first(__p.first), second(__p.second) {}
+
+ template <class _U1, class _U2, __enable_if_t<_CheckArgs::template __is_pair_constructible<_U1, _U2>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(!_CheckArgs::template __is_implicit<_U1, _U2>())
+ pair(pair<_U1, _U2>&& __p) noexcept(is_nothrow_constructible<first_type, _U1&&>::value &&
+ is_nothrow_constructible<second_type, _U2&&>::value)
+ : first(std::forward<_U1>(__p.first)), second(std::forward<_U2>(__p.second)) {}
+
+# if _LIBCPP_STD_VER >= 23
+ template <class _U1,
+ class _U2,
+ __enable_if_t<_CheckArgs::template __is_pair_constructible<const _U1&&, const _U2&&>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_CheckArgs::template __is_implicit<const _U1&&, const _U2&&>())
+ pair(const pair<_U1, _U2>&& __p) noexcept(is_nothrow_constructible<first_type, const _U1&&>::value &&
+ is_nothrow_constructible<second_type, const _U2&&>::value)
+ : first(std::move(__p.first)), second(std::move(__p.second)) {}
+# endif
+
+# if _LIBCPP_STD_VER >= 23
+ // TODO: Remove this workaround in LLVM 20. The bug got fixed in Clang 18.
+ // This is a workaround for http://llvm.org/PR60710. We should be able to remove it once Clang is fixed.
+ template <class _PairLike>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __pair_like_explicit_wknd() {
+ if constexpr (__pair_like_no_subrange<_PairLike>) {
+ return !is_convertible_v<decltype(std::get<0>(std::declval<_PairLike&&>())), first_type> ||
+ !is_convertible_v<decltype(std::get<1>(std::declval<_PairLike&&>())), second_type>;
+ }
+ return false;
+ }
+
+ template <__pair_like_no_subrange _PairLike>
+ requires(is_constructible_v<first_type, decltype(std::get<0>(std::declval<_PairLike &&>()))> &&
+ is_constructible_v<second_type, decltype(std::get<1>(std::declval<_PairLike &&>()))>)
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(__pair_like_explicit_wknd<_PairLike>()) pair(_PairLike&& __p)
+ : first(std::get<0>(std::forward<_PairLike>(__p))), second(std::get<1>(std::forward<_PairLike>(__p))) {}
+# endif
+
+ template <class... _Args1, class... _Args2>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ pair(piecewise_construct_t __pc, tuple<_Args1...> __first_args, tuple<_Args2...> __second_args) noexcept(
+ is_nothrow_constructible<first_type, _Args1...>::value && is_nothrow_constructible<second_type, _Args2...>::value)
+ : pair(__pc,
+ __first_args,
+ __second_args,
+ typename __make_tuple_indices<sizeof...(_Args1)>::type(),
+ typename __make_tuple_indices<sizeof...(_Args2) >::type()) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair&
+ operator=(__conditional_t<!__has_defaulted_members::value && is_copy_assignable<first_type>::value &&
+ is_copy_assignable<second_type>::value,
+ pair,
+ __nat> const& __p) noexcept(is_nothrow_copy_assignable<first_type>::value &&
+ is_nothrow_copy_assignable<second_type>::value) {
+ first = __p.first;
+ second = __p.second;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair&
+ operator=(__conditional_t<!__has_defaulted_members::value && is_move_assignable<first_type>::value &&
+ is_move_assignable<second_type>::value,
+ pair,
+ __nat>&& __p) noexcept(is_nothrow_move_assignable<first_type>::value &&
+ is_nothrow_move_assignable<second_type>::value) {
+ first = std::forward<first_type>(__p.first);
+ second = std::forward<second_type>(__p.second);
+ return *this;
+ }
+
+ template <
+ class _U1,
+ class _U2,
+ __enable_if_t<is_assignable<first_type&, _U1 const&>::value && is_assignable<second_type&, _U2 const&>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair& operator=(pair<_U1, _U2> const& __p) {
+ first = __p.first;
+ second = __p.second;
+ return *this;
+ }
+
+ template <class _U1,
+ class _U2,
+ __enable_if_t<is_assignable<first_type&, _U1>::value && is_assignable<second_type&, _U2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair& operator=(pair<_U1, _U2>&& __p) {
+ first = std::forward<_U1>(__p.first);
+ second = std::forward<_U2>(__p.second);
+ return *this;
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ template <class = void>
+ _LIBCPP_HIDE_FROM_ABI constexpr const pair& operator=(pair const& __p) const
+ noexcept(is_nothrow_copy_assignable_v<const first_type> && is_nothrow_copy_assignable_v<const second_type>)
+ requires(is_copy_assignable_v<const first_type> && is_copy_assignable_v<const second_type>)
+ {
+ first = __p.first;
+ second = __p.second;
+ return *this;
+ }
+
+ template <class = void>
+ _LIBCPP_HIDE_FROM_ABI constexpr const pair& operator=(pair&& __p) const
+ noexcept(is_nothrow_assignable_v<const first_type&, first_type> &&
+ is_nothrow_assignable_v<const second_type&, second_type>)
+ requires(is_assignable_v<const first_type&, first_type> && is_assignable_v<const second_type&, second_type>)
+ {
+ first = std::forward<first_type>(__p.first);
+ second = std::forward<second_type>(__p.second);
+ return *this;
+ }
+
+ template <class _U1, class _U2>
+ _LIBCPP_HIDE_FROM_ABI constexpr const pair& operator=(const pair<_U1, _U2>& __p) const
+ requires(is_assignable_v<const first_type&, const _U1&> && is_assignable_v<const second_type&, const _U2&>)
+ {
+ first = __p.first;
+ second = __p.second;
+ return *this;
+ }
+
+ template <class _U1, class _U2>
+ _LIBCPP_HIDE_FROM_ABI constexpr const pair& operator=(pair<_U1, _U2>&& __p) const
+ requires(is_assignable_v<const first_type&, _U1> && is_assignable_v<const second_type&, _U2>)
+ {
+ first = std::forward<_U1>(__p.first);
+ second = std::forward<_U2>(__p.second);
+ return *this;
+ }
+
+ template <__pair_like_no_subrange _PairLike>
+ requires(__different_from<_PairLike, pair> &&
+ is_assignable_v<first_type&, decltype(std::get<0>(std::declval<_PairLike>()))> &&
+ is_assignable_v<second_type&, decltype(std::get<1>(std::declval<_PairLike>()))>)
+ _LIBCPP_HIDE_FROM_ABI constexpr pair& operator=(_PairLike&& __p) {
+ first = std::get<0>(std::forward<_PairLike>(__p));
+ second = std::get<1>(std::forward<_PairLike>(__p));
+ return *this;
+ }
+
+ template <__pair_like_no_subrange _PairLike>
+ requires(__different_from<_PairLike, pair> &&
+ is_assignable_v<first_type const&, decltype(std::get<0>(std::declval<_PairLike>()))> &&
+ is_assignable_v<second_type const&, decltype(std::get<1>(std::declval<_PairLike>()))>)
+ _LIBCPP_HIDE_FROM_ABI constexpr pair const& operator=(_PairLike&& __p) const {
+ first = std::get<0>(std::forward<_PairLike>(__p));
+ second = std::get<1>(std::forward<_PairLike>(__p));
+ return *this;
+ }
+# endif // _LIBCPP_STD_VER >= 23
+
+ // Prior to C++23, we provide an approximation of constructors and assignment operators from
+ // pair-like types. This was historically provided as an extension.
+# if _LIBCPP_STD_VER < 23
+ // from std::tuple
+ template <class _U1,
+ class _U2,
+ __enable_if_t<is_convertible<_U1 const&, _T1>::value && is_convertible<_U2 const&, _T2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair(tuple<_U1, _U2> const& __p)
+ : first(std::get<0>(__p)), second(std::get<1>(__p)) {}
+
+ template < class _U1,
+ class _U2,
+ __enable_if_t<is_constructible<_T1, _U1 const&>::value && is_constructible<_T2, _U2 const&>::value &&
+ !(is_convertible<_U1 const&, _T1>::value && is_convertible<_U2 const&, _T2>::value),
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit pair(tuple<_U1, _U2> const& __p)
+ : first(std::get<0>(__p)), second(std::get<1>(__p)) {}
+
+ template <class _U1,
+ class _U2,
+ __enable_if_t<is_convertible<_U1, _T1>::value && is_convertible<_U2, _T2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair(tuple<_U1, _U2>&& __p)
+ : first(std::get<0>(std::move(__p))), second(std::get<1>(std::move(__p))) {}
+
+ template <class _U1,
+ class _U2,
+ __enable_if_t<is_constructible<_T1, _U1>::value && is_constructible<_T2, _U2>::value &&
+ !(is_convertible<_U1, _T1>::value && is_convertible<_U2, _T2>::value) > = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit pair(tuple<_U1, _U2>&& __p)
+ : first(std::get<0>(std::move(__p))), second(std::get<1>(std::move(__p))) {}
+
+ template <class _U1,
+ class _U2,
+ __enable_if_t<is_assignable<_T1&, _U1 const&>::value && is_assignable<_T2&, _U2 const&>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair& operator=(tuple<_U1, _U2> const& __p) {
+ first = std::get<0>(__p);
+ second = std::get<1>(__p);
+ return *this;
+ }
+
+ template <class _U1,
+ class _U2,
+ __enable_if_t<is_assignable<_T1&, _U1&&>::value && is_assignable<_T2&, _U2&&>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair& operator=(tuple<_U1, _U2>&& __p) {
+ first = std::get<0>(std::move(__p));
+ second = std::get<1>(std::move(__p));
+ return *this;
+ }
+
+ // from std::array
+ template <class _Up,
+ __enable_if_t<is_convertible<_Up const&, _T1>::value && is_convertible<_Up const&, _T2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair(array<_Up, 2> const& __p) : first(__p[0]), second(__p[1]) {}
+
+ template <class _Up,
+ __enable_if_t<is_constructible<_T1, _Up const&>::value && is_constructible<_T2, _Up const&>::value &&
+ !(is_convertible<_Up const&, _T1>::value && is_convertible<_Up const&, _T2>::value),
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit pair(array<_Up, 2> const& __p)
+ : first(__p[0]), second(__p[1]) {}
+
+ template <class _Up, __enable_if_t< is_convertible<_Up, _T1>::value && is_convertible<_Up, _T2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair(array<_Up, 2>&& __p)
+ : first(std::move(__p)[0]), second(std::move(__p)[1]) {}
+
+ template <class _Up,
+ __enable_if_t<is_constructible<_T1, _Up>::value && is_constructible<_T2, _Up>::value &&
+ !(is_convertible<_Up, _T1>::value && is_convertible<_Up, _T2>::value),
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit pair(array<_Up, 2>&& __p)
+ : first(std::move(__p)[0]), second(std::move(__p)[1]) {}
+
+ template <class _Up,
+ __enable_if_t<is_assignable<_T1&, _Up const&>::value && is_assignable<_T2&, _Up const&>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair& operator=(array<_Up, 2> const& __p) {
+ first = std::get<0>(__p);
+ second = std::get<1>(__p);
+ return *this;
+ }
+
+ template <class _Up, __enable_if_t<is_assignable<_T1&, _Up>::value && is_assignable<_T2&, _Up>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair& operator=(array<_Up, 2>&& __p) {
+ first = std::get<0>(std::move(__p));
+ second = std::get<1>(std::move(__p));
+ return *this;
+ }
+# endif // _LIBCPP_STD_VER < 23
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(pair& __p)
+ _NOEXCEPT_(__is_nothrow_swappable_v<first_type>&& __is_nothrow_swappable_v<second_type>) {
+ using std::swap;
+ swap(first, __p.first);
+ swap(second, __p.second);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI constexpr void swap(const pair& __p) const
+ noexcept(__is_nothrow_swappable_v<const first_type> && __is_nothrow_swappable_v<const second_type>) {
+ using std::swap;
+ swap(first, __p.first);
+ swap(second, __p.second);
+ }
+#endif
+
+private:
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ pair(piecewise_construct_t,
+ tuple<_Args1...>& __first_args,
+ tuple<_Args2...>& __second_args,
+ __tuple_indices<_I1...>,
+ __tuple_indices<_I2...>)
+ : first(std::forward<_Args1>(std::get<_I1>(__first_args))...),
+ second(std::forward<_Args2>(std::get<_I2>(__second_args))...) {}
+#endif
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _T1, class _T2>
+pair(_T1, _T2) -> pair<_T1, _T2>;
+#endif
+
+// [pairs.spec], specialized algorithms
+
+template <class _T1, class _T2, class _U1, class _U2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator==(const pair<_T1, _T2>& __x, const pair<_U1, _U2>& __y) {
+ return __x.first == __y.first && __x.second == __y.second;
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _T1, class _T2, class _U1, class _U2>
+_LIBCPP_HIDE_FROM_ABI constexpr common_comparison_category_t< __synth_three_way_result<_T1, _U1>,
+ __synth_three_way_result<_T2, _U2> >
+operator<=>(const pair<_T1, _T2>& __x, const pair<_U1, _U2>& __y) {
+ if (auto __c = std::__synth_three_way(__x.first, __y.first); __c != 0) {
+ return __c;
+ }
+ return std::__synth_three_way(__x.second, __y.second);
+}
+
+#else // _LIBCPP_STD_VER >= 20
+
+template <class _T1, class _T2, class _U1, class _U2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator!=(const pair<_T1, _T2>& __x, const pair<_U1, _U2>& __y) {
+ return !(__x == __y);
+}
+
+template <class _T1, class _T2, class _U1, class _U2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator<(const pair<_T1, _T2>& __x, const pair<_U1, _U2>& __y) {
+ return __x.first < __y.first || (!(__y.first < __x.first) && __x.second < __y.second);
+}
+
+template <class _T1, class _T2, class _U1, class _U2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator>(const pair<_T1, _T2>& __x, const pair<_U1, _U2>& __y) {
+ return __y < __x;
+}
+
+template <class _T1, class _T2, class _U1, class _U2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator>=(const pair<_T1, _T2>& __x, const pair<_U1, _U2>& __y) {
+ return !(__x < __y);
+}
+
+template <class _T1, class _T2, class _U1, class _U2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator<=(const pair<_T1, _T2>& __x, const pair<_U1, _U2>& __y) {
+ return !(__y < __x);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 23
+template <class _T1, class _T2, class _U1, class _U2, template <class> class _TQual, template <class> class _UQual>
+ requires requires {
+ typename pair<common_reference_t<_TQual<_T1>, _UQual<_U1>>, common_reference_t<_TQual<_T2>, _UQual<_U2>>>;
+ }
+struct basic_common_reference<pair<_T1, _T2>, pair<_U1, _U2>, _TQual, _UQual> {
+ using type = pair<common_reference_t<_TQual<_T1>, _UQual<_U1>>, common_reference_t<_TQual<_T2>, _UQual<_U2>>>;
+};
+
+template <class _T1, class _T2, class _U1, class _U2>
+ requires requires { typename pair<common_type_t<_T1, _U1>, common_type_t<_T2, _U2>>; }
+struct common_type<pair<_T1, _T2>, pair<_U1, _U2>> {
+ using type = pair<common_type_t<_T1, _U1>, common_type_t<_T2, _U2>>;
+};
+#endif // _LIBCPP_STD_VER >= 23
+
+template <class _T1, class _T2, __enable_if_t<__is_swappable_v<_T1> && __is_swappable_v<_T2>, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(pair<_T1, _T2>& __x, pair<_T1, _T2>& __y)
+ _NOEXCEPT_(__is_nothrow_swappable_v<_T1>&& __is_nothrow_swappable_v<_T2>) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 23
+template <class _T1, class _T2>
+ requires(__is_swappable_v<const _T1> && __is_swappable_v<const _T2>)
+_LIBCPP_HIDE_FROM_ABI constexpr void
+swap(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) noexcept(noexcept(__x.swap(__y))) {
+ __x.swap(__y);
+}
+#endif
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX14 pair<typename __unwrap_ref_decay<_T1>::type, typename __unwrap_ref_decay<_T2>::type>
+make_pair(_T1&& __t1, _T2&& __t2) {
+ return pair<typename __unwrap_ref_decay<_T1>::type, typename __unwrap_ref_decay<_T2>::type>(
+ std::forward<_T1>(__t1), std::forward<_T2>(__t2));
+}
+
+template <class _T1, class _T2>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<pair<_T1, _T2> > : public integral_constant<size_t, 2> {};
+
+template <size_t _Ip, class _T1, class _T2>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, pair<_T1, _T2> > {
+ static_assert(_Ip < 2, "Index out of bounds in std::tuple_element<std::pair<T1, T2>>");
+};
+
+template <class _T1, class _T2>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<0, pair<_T1, _T2> > {
+ using type _LIBCPP_NODEBUG = _T1;
+};
+
+template <class _T1, class _T2>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<1, pair<_T1, _T2> > {
+ using type _LIBCPP_NODEBUG = _T2;
+};
+
+template <size_t _Ip>
+struct __get_pair;
+
+template <>
+struct __get_pair<0> {
+ template <class _T1, class _T2>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _T1& get(pair<_T1, _T2>& __p) _NOEXCEPT {
+ return __p.first;
+ }
+
+ template <class _T1, class _T2>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _T1& get(const pair<_T1, _T2>& __p) _NOEXCEPT {
+ return __p.first;
+ }
+
+ template <class _T1, class _T2>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _T1&& get(pair<_T1, _T2>&& __p) _NOEXCEPT {
+ return std::forward<_T1>(__p.first);
+ }
+
+ template <class _T1, class _T2>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _T1&& get(const pair<_T1, _T2>&& __p) _NOEXCEPT {
+ return std::forward<const _T1>(__p.first);
+ }
+};
+
+template <>
+struct __get_pair<1> {
+ template <class _T1, class _T2>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _T2& get(pair<_T1, _T2>& __p) _NOEXCEPT {
+ return __p.second;
+ }
+
+ template <class _T1, class _T2>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _T2& get(const pair<_T1, _T2>& __p) _NOEXCEPT {
+ return __p.second;
+ }
+
+ template <class _T1, class _T2>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _T2&& get(pair<_T1, _T2>&& __p) _NOEXCEPT {
+ return std::forward<_T2>(__p.second);
+ }
+
+ template <class _T1, class _T2>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _T2&& get(const pair<_T1, _T2>&& __p) _NOEXCEPT {
+ return std::forward<const _T2>(__p.second);
+ }
+};
+
+template <size_t _Ip, class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, pair<_T1, _T2> >::type&
+get(pair<_T1, _T2>& __p) _NOEXCEPT {
+ return __get_pair<_Ip>::get(__p);
+}
+
+template <size_t _Ip, class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, pair<_T1, _T2> >::type&
+get(const pair<_T1, _T2>& __p) _NOEXCEPT {
+ return __get_pair<_Ip>::get(__p);
+}
+
+template <size_t _Ip, class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
+get(pair<_T1, _T2>&& __p) _NOEXCEPT {
+ return __get_pair<_Ip>::get(std::move(__p));
+}
+
+template <size_t _Ip, class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
+get(const pair<_T1, _T2>&& __p) _NOEXCEPT {
+ return __get_pair<_Ip>::get(std::move(__p));
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1& get(pair<_T1, _T2>& __p) _NOEXCEPT {
+ return __get_pair<0>::get(__p);
+}
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1 const& get(pair<_T1, _T2> const& __p) _NOEXCEPT {
+ return __get_pair<0>::get(__p);
+}
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1&& get(pair<_T1, _T2>&& __p) _NOEXCEPT {
+ return __get_pair<0>::get(std::move(__p));
+}
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1 const&& get(pair<_T1, _T2> const&& __p) _NOEXCEPT {
+ return __get_pair<0>::get(std::move(__p));
+}
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1& get(pair<_T2, _T1>& __p) _NOEXCEPT {
+ return __get_pair<1>::get(__p);
+}
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1 const& get(pair<_T2, _T1> const& __p) _NOEXCEPT {
+ return __get_pair<1>::get(__p);
+}
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1&& get(pair<_T2, _T1>&& __p) _NOEXCEPT {
+ return __get_pair<1>::get(std::move(__p));
+}
+
+template <class _T1, class _T2>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1 const&& get(pair<_T2, _T1> const&& __p) _NOEXCEPT {
+ return __get_pair<1>::get(std::move(__p));
+}
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___UTILITY_PAIR_H
diff --git a/libcxx/include/__cxx03/__utility/piecewise_construct.h b/libcxx/include/__cxx03/__utility/piecewise_construct.h
new file mode 100644
index 00000000000000..52b19d791e1003
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/piecewise_construct.h
@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_PIECEWISE_CONSTRUCT_H
+#define _LIBCPP___UTILITY_PIECEWISE_CONSTRUCT_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct _LIBCPP_TEMPLATE_VIS piecewise_construct_t {
+ explicit piecewise_construct_t() = default;
+};
+
+#if _LIBCPP_STD_VER >= 17
+inline constexpr piecewise_construct_t piecewise_construct = piecewise_construct_t();
+#elif !defined(_LIBCPP_CXX03_LANG)
+constexpr piecewise_construct_t piecewise_construct = piecewise_construct_t();
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_PIECEWISE_CONSTRUCT_H
diff --git a/libcxx/include/__cxx03/__utility/priority_tag.h b/libcxx/include/__cxx03/__utility/priority_tag.h
new file mode 100644
index 00000000000000..a159ce7f1afb34
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/priority_tag.h
@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_PRIORITY_TAG_H
+#define _LIBCPP___UTILITY_PRIORITY_TAG_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t _Ip>
+struct __priority_tag : __priority_tag<_Ip - 1> {};
+template <>
+struct __priority_tag<0> {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_PRIORITY_TAG_H
diff --git a/libcxx/include/__cxx03/__utility/private_constructor_tag.h b/libcxx/include/__cxx03/__utility/private_constructor_tag.h
new file mode 100644
index 00000000000000..462cab48c9eddb
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/private_constructor_tag.h
@@ -0,0 +1,28 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP__UTILITY_PRIVATE_CONSTRUCTOR_TAG_H
+#define _LIBCPP__UTILITY_PRIVATE_CONSTRUCTOR_TAG_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// This tag allows defining non-standard exposition-only constructors while
+// preventing users from being able to use them, since this reserved-name tag
+// needs to be used.
+struct __private_constructor_tag {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP__UTILITY_PRIVATE_CONSTRUCTOR_TAG_H
diff --git a/libcxx/include/__cxx03/__utility/rel_ops.h b/libcxx/include/__cxx03/__utility/rel_ops.h
new file mode 100644
index 00000000000000..a8caf5bdeaf278
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/rel_ops.h
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_REL_OPS_H
+#define _LIBCPP___UTILITY_REL_OPS_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace rel_ops {
+
+template <class _Tp>
+inline _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_HIDE_FROM_ABI bool operator!=(const _Tp& __x, const _Tp& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp>
+inline _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_HIDE_FROM_ABI bool operator>(const _Tp& __x, const _Tp& __y) {
+ return __y < __x;
+}
+
+template <class _Tp>
+inline _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_HIDE_FROM_ABI bool operator<=(const _Tp& __x, const _Tp& __y) {
+ return !(__y < __x);
+}
+
+template <class _Tp>
+inline _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_HIDE_FROM_ABI bool operator>=(const _Tp& __x, const _Tp& __y) {
+ return !(__x < __y);
+}
+
+} // namespace rel_ops
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_REL_OPS_H
diff --git a/libcxx/include/__cxx03/__utility/small_buffer.h b/libcxx/include/__cxx03/__utility/small_buffer.h
new file mode 100644
index 00000000000000..9e13797573d2d7
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/small_buffer.h
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_SMALL_BUFFER_H
+#define _LIBCPP___UTILITY_SMALL_BUFFER_H
+
+#include <__config>
+#include <__memory/construct_at.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_trivially_constructible.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <__utility/exception_guard.h>
+#include <__utility/forward.h>
+#include <cstddef>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+
+// __small_buffer is a helper class to perform the well known SBO (small buffer optimization). It is mainly useful to
+// allow type-erasing classes like move_only_function to store small objects in a local buffer without requiring an
+// allocation.
+//
+// This small buffer class only allows storing trivially relocatable objects inside the local storage to allow
+// __small_buffer to be trivially relocatable itself. Since the buffer doesn't know what's stored inside it, the user
+// has to manage the object's lifetime, in particular the destruction of the object.
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t _BufferSize, size_t _BufferAlignment>
+ requires(_BufferSize > 0 && _BufferAlignment > 0)
+class __small_buffer {
+public:
+ template <class _Tp, class _Decayed = decay_t<_Tp>>
+ static constexpr bool __fits_in_buffer =
+ is_trivially_move_constructible_v<_Decayed> && is_trivially_destructible_v<_Decayed> &&
+ sizeof(_Decayed) <= _BufferSize && alignof(_Decayed) <= _BufferAlignment;
+
+ _LIBCPP_HIDE_FROM_ABI __small_buffer() = default;
+ __small_buffer(const __small_buffer&) = delete;
+ __small_buffer& operator=(const __small_buffer&) = delete;
+ _LIBCPP_HIDE_FROM_ABI ~__small_buffer() = default;
+
+ // Relocates the buffer - __delete() should never be called on a moved-from __small_buffer
+ _LIBCPP_HIDE_FROM_ABI __small_buffer(__small_buffer&&) = default;
+ _LIBCPP_HIDE_FROM_ABI __small_buffer& operator=(__small_buffer&&) = default;
+
+ template <class _Stored>
+ _LIBCPP_HIDE_FROM_ABI _Stored* __get() {
+ if constexpr (__fits_in_buffer<_Stored>)
+ return std::launder(reinterpret_cast<_Stored*>(__buffer_));
+ else
+ return *std::launder(reinterpret_cast<_Stored**>(__buffer_));
+ }
+
+ template <class _Stored>
+ _LIBCPP_HIDE_FROM_ABI _Stored* __alloc() {
+ if constexpr (__fits_in_buffer<_Stored>) {
+ return std::launder(reinterpret_cast<_Stored*>(__buffer_));
+ } else {
+ byte* __allocation = static_cast<byte*>(::operator new[](sizeof(_Stored), align_val_t{alignof(_Stored)}));
+ std::construct_at(reinterpret_cast<byte**>(__buffer_), __allocation);
+ return std::launder(reinterpret_cast<_Stored*>(__allocation));
+ }
+ }
+
+ template <class _Stored>
+ _LIBCPP_HIDE_FROM_ABI void __dealloc() noexcept {
+ if constexpr (!__fits_in_buffer<_Stored>)
+ ::operator delete[](*reinterpret_cast<void**>(__buffer_), sizeof(_Stored), align_val_t{alignof(_Stored)});
+ }
+
+ template <class _Stored, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void __construct(_Args&&... __args) {
+ _Stored* __buffer = __alloc<_Stored>();
+ auto __guard = std::__make_exception_guard([&] { __dealloc<_Stored>(); });
+ std::construct_at(__buffer, std::forward<_Args>(__args)...);
+ __guard.__complete();
+ }
+
+private:
+ alignas(_BufferAlignment) byte __buffer_[_BufferSize];
+};
+
+# undef _LIBCPP_SMALL_BUFFER_TRIVIAL_ABI
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+#endif // _LIBCPP___UTILITY_SMALL_BUFFER_H
diff --git a/libcxx/include/__cxx03/__utility/swap.h b/libcxx/include/__cxx03/__utility/swap.h
new file mode 100644
index 00000000000000..ab88b8e0a0b531
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/swap.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_SWAP_H
+#define _LIBCPP___UTILITY_SWAP_H
+
+#include <__config>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_swappable.h>
+#include <__utility/declval.h>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Tp>
+using __swap_result_t = __enable_if_t<is_move_constructible<_Tp>::value && is_move_assignable<_Tp>::value>;
+#else
+template <class>
+using __swap_result_t = void;
+#endif
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI __swap_result_t<_Tp> _LIBCPP_CONSTEXPR_SINCE_CXX20 swap(_Tp& __x, _Tp& __y)
+ _NOEXCEPT_(is_nothrow_move_constructible<_Tp>::value&& is_nothrow_move_assignable<_Tp>::value) {
+ _Tp __t(std::move(__x));
+ __x = std::move(__y);
+ __y = std::move(__t);
+}
+
+template <class _Tp, size_t _Np, __enable_if_t<__is_swappable_v<_Tp>, int> >
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(_Tp (&__a)[_Np], _Tp (&__b)[_Np])
+ _NOEXCEPT_(__is_nothrow_swappable_v<_Tp>) {
+ for (size_t __i = 0; __i != _Np; ++__i) {
+ swap(__a[__i], __b[__i]);
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___UTILITY_SWAP_H
diff --git a/libcxx/include/__cxx03/__utility/to_underlying.h b/libcxx/include/__cxx03/__utility/to_underlying.h
new file mode 100644
index 00000000000000..77587108f20dcc
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/to_underlying.h
@@ -0,0 +1,38 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_TO_UNDERLYING_H
+#define _LIBCPP___UTILITY_TO_UNDERLYING_H
+
+#include <__config>
+#include <__type_traits/underlying_type.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr typename underlying_type<_Tp>::type __to_underlying(_Tp __val) noexcept {
+ return static_cast<typename underlying_type<_Tp>::type>(__val);
+}
+#endif // !_LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 23
+template <class _Tp>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr underlying_type_t<_Tp> to_underlying(_Tp __val) noexcept {
+ return std::__to_underlying(__val);
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_TO_UNDERLYING_H
diff --git a/libcxx/include/__cxx03/__utility/unreachable.h b/libcxx/include/__cxx03/__utility/unreachable.h
new file mode 100644
index 00000000000000..d833f74c2e4f1c
--- /dev/null
+++ b/libcxx/include/__cxx03/__utility/unreachable.h
@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___UTILITY_UNREACHABLE_H
+#define _LIBCPP___UTILITY_UNREACHABLE_H
+
+#include <__assert>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI inline void __libcpp_unreachable() {
+ _LIBCPP_ASSERT_INTERNAL(false, "std::unreachable() was reached");
+ __builtin_unreachable();
+}
+
+#if _LIBCPP_STD_VER >= 23
+
+[[noreturn]] _LIBCPP_HIDE_FROM_ABI inline void unreachable() { __libcpp_unreachable(); }
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___UTILITY_UNREACHABLE_H
diff --git a/libcxx/include/__cxx03/__variant/monostate.h b/libcxx/include/__cxx03/__variant/monostate.h
new file mode 100644
index 00000000000000..16f156609eb7df
--- /dev/null
+++ b/libcxx/include/__cxx03/__variant/monostate.h
@@ -0,0 +1,64 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___VARIANT_MONOSTATE_H
+#define _LIBCPP___VARIANT_MONOSTATE_H
+
+#include <__compare/ordering.h>
+#include <__config>
+#include <__functional/hash.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+struct _LIBCPP_TEMPLATE_VIS monostate {};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator==(monostate, monostate) noexcept { return true; }
+
+# if _LIBCPP_STD_VER >= 20
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr strong_ordering operator<=>(monostate, monostate) noexcept {
+ return strong_ordering::equal;
+}
+
+# else // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator!=(monostate, monostate) noexcept { return false; }
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator<(monostate, monostate) noexcept { return false; }
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator>(monostate, monostate) noexcept { return false; }
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator<=(monostate, monostate) noexcept { return true; }
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr bool operator>=(monostate, monostate) noexcept { return true; }
+
+# endif // _LIBCPP_STD_VER >= 20
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<monostate> {
+ using argument_type = monostate;
+ using result_type = size_t;
+
+ inline _LIBCPP_HIDE_FROM_ABI result_type operator()(const argument_type&) const _NOEXCEPT {
+ return 66740831; // return a fundamentally attractive random value.
+ }
+};
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___VARIANT_MONOSTATE_H
diff --git a/libcxx/include/__cxx03/__verbose_abort b/libcxx/include/__cxx03/__verbose_abort
new file mode 100644
index 00000000000000..195ce65b721ff7
--- /dev/null
+++ b/libcxx/include/__cxx03/__verbose_abort
@@ -0,0 +1,52 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___VERBOSE_ABORT
+#define _LIBCPP___VERBOSE_ABORT
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// This function should never be called directly from the code -- it should only be called through
+// the _LIBCPP_VERBOSE_ABORT macro.
+_LIBCPP_NORETURN _LIBCPP_AVAILABILITY_VERBOSE_ABORT _LIBCPP_OVERRIDABLE_FUNC_VIS
+_LIBCPP_ATTRIBUTE_FORMAT(__printf__, 1, 2) void __libcpp_verbose_abort(const char* __format, ...);
+
+// _LIBCPP_VERBOSE_ABORT(format, args...)
+//
+// This macro is used to abort the program abnormally while providing additional diagnostic information.
+//
+// The first argument is a printf-style format string, and the remaining arguments are values to format
+// into the format-string. This macro can be customized by users to provide fine-grained control over
+// how verbose termination is triggered.
+//
+// If the user does not supply their own version of the _LIBCPP_VERBOSE_ABORT macro, we pick the default
+// behavior based on whether we know the built library we're running against provides support for the
+// verbose termination handler or not. If it does, we call it. If it doesn't, we call __builtin_abort to
+// make sure that the program terminates but without taking any complex dependencies in this header.
+#if !defined(_LIBCPP_VERBOSE_ABORT)
+
+# if !_LIBCPP_AVAILABILITY_HAS_VERBOSE_ABORT
+// The decltype is there to suppress -Wunused warnings in this configuration.
+void __use(const char*, ...);
+# define _LIBCPP_VERBOSE_ABORT(...) (decltype(::std::__use(__VA_ARGS__))(), __builtin_abort())
+# else
+# define _LIBCPP_VERBOSE_ABORT(...) ::std::__libcpp_verbose_abort(__VA_ARGS__)
+# endif
+
+#endif // !defined(_LIBCPP_VERBOSE_ABORT)
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___VERBOSE_ABORT
diff --git a/libcxx/include/__cxx03/algorithm b/libcxx/include/__cxx03/algorithm
new file mode 100644
index 00000000000000..698e6f5cb7ad1f
--- /dev/null
+++ b/libcxx/include/__cxx03/algorithm
@@ -0,0 +1,2049 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_ALGORITHM
+#define _LIBCPP_ALGORITHM
+
+/*
+ algorithm synopsis
+
+#include <initializer_list>
+
+namespace std
+{
+
+namespace ranges {
+
+ // [algorithms.results], algorithm result types
+ template <class I, class F>
+ struct in_fun_result; // since C++20
+
+ template <class I1, class I2>
+ struct in_in_result; // since C++20
+
+ template <class I, class O>
+ struct in_out_result; // since C++20
+
+ template <class I1, class I2, class O>
+ struct in_in_out_result; // since C++20
+
+ template <class I, class O1, class O2>
+ struct in_out_out_result; // since C++20
+
+ template <class I1, class I2>
+ struct min_max_result; // since C++20
+
+ template <class I>
+ struct in_found_result; // since C++20
+
+ template <class I, class T>
+ struct in_value_result; // since C++23
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less> // since C++20
+ constexpr I min_element(I first, S last, Comp comp = {}, Proj proj = {});
+
+ template<forward_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less> // since C++20
+ constexpr borrowed_iterator_t<R> min_element(R&& r, Comp comp = {}, Proj proj = {});
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
+ constexpr I ranges::max_element(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ constexpr borrowed_iterator_t<R> ranges::max_element(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<class I1, class I2>
+ using mismatch_result = in_in_result<I1, I2>;
+
+ template <input_iterator I1, sentinel_for<_I1> S1, input_iterator I2, sentinel_for<_I2> S2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+ constexpr mismatch_result<_I1, _I2> // since C++20
+ mismatch()(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {})
+
+ template <input_range R1, input_range R2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+ constexpr mismatch_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>>
+ mismatch(R1&& r1, R2&& r2, Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {}) // since C++20
+
+ requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
+ constexpr I find(I first, S last, const T& value, Proj proj = {}); // since C++20
+
+ template<input_range R, class T, class Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
+ constexpr borrowed_iterator_t<R>
+ find(R&& r, const T& value, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr I find_if(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr borrowed_iterator_t<R>
+ find_if(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr I find_if_not(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr borrowed_iterator_t<R>
+ find_if_not(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
+ constexpr subrange<I> find_last(I first, S last, const T& value, Proj proj = {}); // since C++23
+
+ template<forward_range R, class T, class Proj = identity>
+ requires
+ indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
+ constexpr borrowed_subrange_t<R> find_last(R&& r, const T& value, Proj proj = {}); // since C++23
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr subrange<I> find_last_if(I first, S last, Pred pred, Proj proj = {}); // since C++23
+
+ template<forward_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr borrowed_subrange_t<R> find_last_if(R&& r, Pred pred, Proj proj = {}); // since C++23
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr subrange<I> find_last_if_not(I first, S last, Pred pred, Proj proj = {}); // since C++23
+
+ template<forward_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr borrowed_subrange_t<R> find_last_if_not(R&& r, Pred pred, Proj proj = {}); // since C++23
+
+ template<class T, class Proj = identity,
+ indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
+ constexpr const T& min(const T& a, const T& b, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<copyable T, class Proj = identity,
+ indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
+ constexpr T min(initializer_list<T> r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
+ constexpr range_value_t<R>
+ min(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<class T, class Proj = identity,
+ indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
+ constexpr const T& max(const T& a, const T& b, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<copyable T, class Proj = identity,
+ indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
+ constexpr T max(initializer_list<T> r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
+ constexpr range_value_t<R>
+ max(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<class I, class O>
+ using unary_transform_result = in_out_result<I, O>; // since C++20
+
+ template<class I1, class I2, class O>
+ using binary_transform_result = in_in_out_result<I1, I2, O>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, weakly_incrementable O,
+ copy_constructible F, class Proj = identity>
+ requires indirectly_writable<O, indirect_result_t<F&, projected<I, Proj>>>
+ constexpr ranges::unary_transform_result<I, O>
+ transform(I first1, S last1, O result, F op, Proj proj = {}); // since C++20
+
+ template<input_range R, weakly_incrementable O, copy_constructible F,
+ class Proj = identity>
+ requires indirectly_writable<O, indirect_result_t<F&, projected<iterator_t<R>, Proj>>>
+ constexpr ranges::unary_transform_result<borrowed_iterator_t<R>, O>
+ transform(R&& r, O result, F op, Proj proj = {}); // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ weakly_incrementable O, copy_constructible F, class Proj1 = identity,
+ class Proj2 = identity>
+ requires indirectly_writable<O, indirect_result_t<F&, projected<I1, Proj1>,
+ projected<I2, Proj2>>>
+ constexpr ranges::binary_transform_result<I1, I2, O>
+ transform(I1 first1, S1 last1, I2 first2, S2 last2, O result,
+ F binary_op, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, input_range R2, weakly_incrementable O,
+ copy_constructible F, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_writable<O, indirect_result_t<F&, projected<iterator_t<R1>, Proj1>,
+ projected<iterator_t<R2>, Proj2>>>
+ constexpr ranges::binary_transform_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>, O>
+ transform(R1&& r1, R2&& r2, O result,
+ F binary_op, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class T, class Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
+ constexpr iter_difference_t<I>
+ count(I first, S last, const T& value, Proj proj = {}); // since C++20
+
+ template<input_range R, class T, class Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
+ constexpr range_difference_t<R>
+ count(R&& r, const T& value, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr iter_difference_t<I>
+ count_if(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr range_difference_t<R>
+ count_if(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<class T>
+ using minmax_result = min_max_result<T>;
+
+ template<class T, class Proj = identity,
+ indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
+ constexpr ranges::minmax_result<const T&>
+ minmax(const T& a, const T& b, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<copyable T, class Proj = identity,
+ indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
+ constexpr ranges::minmax_result<T>
+ minmax(initializer_list<T> r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
+ constexpr ranges::minmax_result<range_value_t<R>>
+ minmax(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<class I>
+ using minmax_element_result = min_max_result<I>;
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
+ constexpr ranges::minmax_element_result<I>
+ minmax_element(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ constexpr ranges::minmax_element_result<borrowed_iterator_t<R>>
+ minmax_element(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_iterator I1, sentinel_for<I1> S1,
+ forward_iterator I2, sentinel_for<I2> S2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+ constexpr bool contains_subrange(I1 first1, S1 last1, I2 first2, S2 last2,
+ Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++23
+
+ template<forward_range R1, forward_range R2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+ constexpr bool contains_subrange(R1&& r1, R2&& r2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++23
+
+ template<class I, class O>
+ using copy_result = in_out_result<I, O>; // since C++20
+
+ template<class I, class O>
+ using copy_n_result = in_out_result<I, O>; // since C++20
+
+ template<class I, class O>
+ using copy_if_result = in_out_result<I, O>; // since C++20
+
+ template<class I1, class I2>
+ using copy_backward_result = in_out_result<I1, I2>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class T, class Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
+ constexpr bool ranges::contains(I first, S last, const T& value, Proj proj = {}); // since C++23
+
+ template<input_range R, class T, class Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
+ constexpr bool ranges::contains(R&& r, const T& value, Proj proj = {}); // since C++23
+
+ template<input_iterator I, sentinel_for<I> S, weakly_incrementable O>
+ requires indirectly_copyable<I, O>
+ constexpr ranges::copy_result<I, O> ranges::copy(I first, S last, O result); // since C++20
+
+ template<input_range R, weakly_incrementable O>
+ requires indirectly_copyable<iterator_t<R>, O>
+ constexpr ranges::copy_result<borrowed_iterator_t<R>, O> ranges::copy(R&& r, O result); // since C++20
+
+ template<input_iterator I, weakly_incrementable O>
+ requires indirectly_copyable<I, O>
+ constexpr ranges::copy_n_result<I, O>
+ ranges::copy_n(I first, iter_difference_t<I> n, O result); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, weakly_incrementable O, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ requires indirectly_copyable<I, O>
+ constexpr ranges::copy_if_result<I, O>
+ ranges::copy_if(I first, S last, O result, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, weakly_incrementable O, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ requires indirectly_copyable<iterator_t<R>, O>
+ constexpr ranges::copy_if_result<borrowed_iterator_t<R>, O>
+ ranges::copy_if(R&& r, O result, Pred pred, Proj proj = {}); // since C++20
+
+ template<bidirectional_iterator I1, sentinel_for<I1> S1, bidirectional_iterator I2>
+ requires indirectly_copyable<I1, I2>
+ constexpr ranges::copy_backward_result<I1, I2>
+ ranges::copy_backward(I1 first, S1 last, I2 result); // since C++20
+
+ template<bidirectional_range R, bidirectional_iterator I>
+ requires indirectly_copyable<iterator_t<R>, I>
+ constexpr ranges::copy_backward_result<borrowed_iterator_t<R>, I>
+ ranges::copy_backward(R&& r, I result); // since C++20
+
+ template<class I, class F>
+ using for_each_result = in_fun_result<I, F>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirectly_unary_invocable<projected<I, Proj>> Fun>
+ constexpr ranges::for_each_result<I, Fun>
+ ranges::for_each(I first, S last, Fun f, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirectly_unary_invocable<projected<iterator_t<R>, Proj>> Fun>
+ constexpr ranges::for_each_result<borrowed_iterator_t<R>, Fun>
+ ranges::for_each(R&& r, Fun f, Proj proj = {}); // since C++20
+
+ template<input_iterator I, class Proj = identity,
+ indirectly_unary_invocable<projected<I, Proj>> Fun>
+ constexpr ranges::for_each_n_result<I, Fun>
+ ranges::for_each_n(I first, iter_difference_t<I> n, Fun f, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr bool ranges::is_partitioned(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr bool ranges::is_partitioned(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr I
+ ranges::push_heap(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr borrowed_iterator_t<R>
+ ranges::push_heap(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr I
+ ranges::pop_heap(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr borrowed_iterator_t<R>
+ ranges::pop_heap(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr I
+ ranges::make_heap(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr borrowed_iterator_t<R>
+ ranges::make_heap(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr I
+ ranges::sort_heap(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr borrowed_iterator_t<R>
+ ranges::sort_heap(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
+ constexpr bool is_heap(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ constexpr bool is_heap(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
+ constexpr I is_heap_until(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ constexpr borrowed_iterator_t<R>
+ is_heap_until(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<bidirectional_iterator I, sentinel_for<I> S>
+ requires permutable<I>
+ constexpr I ranges::reverse(I first, S last); // since C++20
+
+ template<bidirectional_range R>
+ requires permutable<iterator_t<R>>
+ constexpr borrowed_iterator_t<R> ranges::reverse(R&& r); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr I
+ ranges::sort(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr borrowed_iterator_t<R>
+ ranges::sort(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ I ranges::stable_sort(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ borrowed_iterator_t<R>
+ ranges::stable_sort(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr I
+ ranges::partial_sort(I first, I middle, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr borrowed_iterator_t<R>
+ ranges::partial_sort(R&& r, iterator_t<R> middle, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<class T, output_iterator<const T&> O, sentinel_for<O> S>
+ constexpr O ranges::fill(O first, S last, const T& value); // since C++20
+
+ template<class T, output_range<const T&> R>
+ constexpr borrowed_iterator_t<R> ranges::fill(R&& r, const T& value); // since C++20
+
+ template<class T, output_iterator<const T&> O>
+ constexpr O ranges::fill_n(O first, iter_difference_t<O> n, const T& value); // since C++20
+
+ template<input_or_output_iterator O, sentinel_for<O> S, copy_constructible F>
+ requires invocable<F&> && indirectly_writable<O, invoke_result_t<F&>>
+ constexpr O generate(O first, S last, F gen); // since C++20
+
+ template<class ExecutionPolicy, class ForwardIterator, class Generator>
+ void generate(ExecutionPolicy&& exec,
+ ForwardIterator first, ForwardIterator last,
+ Generator gen); // since C++17
+
+ template<class R, copy_constructible F>
+ requires invocable<F&> && output_range<R, invoke_result_t<F&>>
+ constexpr borrowed_iterator_t<R> generate(R&& r, F gen); // since C++20
+
+ template<input_or_output_iterator O, copy_constructible F>
+ requires invocable<F&> && indirectly_writable<O, invoke_result_t<F&>>
+ constexpr O generate_n(O first, iter_difference_t<O> n, F gen); // since C++20
+
+ template<class ExecutionPolicy, class ForwardIterator, class Size, class Generator>
+ ForwardIterator generate_n(ExecutionPolicy&& exec,
+ ForwardIterator first, Size n, Generator gen); // since C++17
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+ constexpr bool ranges::equal(I1 first1, S1 last1, I2 first2, S2 last2,
+ Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, input_range R2, class Pred = ranges::equal_to,
+ class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+ constexpr bool ranges::equal(R1&& r1, R2&& r2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr bool ranges::all_of(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr bool ranges::all_of(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr bool ranges::any_of(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr bool ranges::any_of(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires (forward_iterator<I1> || sized_sentinel_for<S1, I1>) &&
+ (forward_iterator<I2> || sized_sentinel_for<S2, I2>) &&
+ indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+ constexpr bool ranges::ends_with(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++23
+
+ template<input_range R1, input_range R2, class Pred = ranges::equal_to, class Proj1 = identity,
+ class Proj2 = identity>
+ requires (forward_range<R1> || sized_range<R1>) &&
+ (forward_range<R2> || sized_range<R2>) &&
+ indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+ constexpr bool ranges::ends_with(R1&& r1, R2&& r2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++23
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr bool ranges::none_of(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr bool ranges::none_of(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+ constexpr bool ranges::starts_with(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++23
+
+ template<input_range R1, input_range R2, class Pred = ranges::equal_to, class Proj1 = identity,
+ class Proj2 = identity>
+ requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+ constexpr bool ranges::starts_with(R1&& r1, R2&& r2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++23
+
+ template<input_iterator I1, sentinel_for<I1> S1,
+ random_access_iterator I2, sentinel_for<I2> S2,
+ class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_copyable<I1, I2> && sortable<I2, Comp, Proj2> &&
+ indirect_strict_weak_order<Comp, projected<I1, Proj1>, projected<I2, Proj2>>
+ constexpr partial_sort_copy_result<I1, I2>
+ partial_sort_copy(I1 first, S1 last, I2 result_first, S2 result_last,
+ Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, random_access_range R2, class Comp = ranges::less,
+ class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_copyable<iterator_t<R1>, iterator_t<R2>> &&
+ sortable<iterator_t<R2>, Comp, Proj2> &&
+ indirect_strict_weak_order<Comp, projected<iterator_t<R1>, Proj1>,
+ projected<iterator_t<R2>, Proj2>>
+ constexpr partial_sort_copy_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>>
+ partial_sort_copy(R1&& r, R2&& result_r, Comp comp = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
+ constexpr bool ranges::is_sorted(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ constexpr bool ranges::is_sorted(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
+ constexpr I ranges::is_sorted_until(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
+ constexpr borrowed_iterator_t<R>
+ ranges::is_sorted_until(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr I
+ ranges::nth_element(I first, I nth, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<random_access_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr borrowed_iterator_t<R>
+ ranges::nth_element(R&& r, iterator_t<R> nth, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity,
+ indirect_strict_weak_order<const T*, projected<I, Proj>> Comp = ranges::less> // since C++20
+ constexpr I upper_bound(I first, S last, const T& value, Comp comp = {}, Proj proj = {});
+
+ template<forward_range R, class T, class Proj = identity,
+ indirect_strict_weak_order<const T*, projected<iterator_t<R>, Proj>> Comp =
+ ranges::less>
+ constexpr borrowed_iterator_t<R>
+ upper_bound(R&& r, const T& value, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity,
+ indirect_strict_weak_order<const T*, projected<I, Proj>> Comp = ranges::less>
+ constexpr I lower_bound(I first, S last, const T& value, Comp comp = {},
+ Proj proj = {}); // since C++20
+ template<forward_range R, class T, class Proj = identity,
+ indirect_strict_weak_order<const T*, projected<iterator_t<R>, Proj>> Comp =
+ ranges::less>
+ constexpr borrowed_iterator_t<R>
+ lower_bound(R&& r, const T& value, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity,
+ indirect_strict_weak_order<const T*, projected<I, Proj>> Comp = ranges::less>
+ constexpr bool binary_search(I first, S last, const T& value, Comp comp = {},
+ Proj proj = {}); // since C++20
+
+ template<forward_range R, class T, class Proj = identity,
+ indirect_strict_weak_order<const T*, projected<iterator_t<R>, Proj>> Comp =
+ ranges::less>
+ constexpr bool binary_search(R&& r, const T& value, Comp comp = {},
+ Proj proj = {}); // since C++20
+
+ template<permutable I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr subrange<I>
+ partition(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ requires permutable<iterator_t<R>>
+ constexpr borrowed_subrange_t<R>
+ partition(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<bidirectional_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ requires permutable<I>
+ subrange<I> stable_partition(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<bidirectional_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ requires permutable<iterator_t<R>>
+ borrowed_subrange_t<R> stable_partition(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, forward_iterator I2, sentinel_for<I2> S2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+ constexpr I1 ranges::find_first_of(I1 first1, S1 last1, I2 first2, S2 last2,
+ Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, forward_range R2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+ constexpr borrowed_iterator_t<R1>
+ ranges::find_first_of(R1&& r1, R2&& r2,
+ Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_binary_predicate<projected<I, Proj>,
+ projected<I, Proj>> Pred = ranges::equal_to>
+ constexpr I ranges::adjacent_find(I first, S last, Pred pred = {}, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_binary_predicate<projected<iterator_t<R>, Proj>,
+ projected<iterator_t<R>, Proj>> Pred = ranges::equal_to>
+ constexpr borrowed_iterator_t<R> ranges::adjacent_find(R&& r, Pred pred = {}, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class T1, class T2, class Proj = identity>
+ requires indirectly_writable<I, const T2&> &&
+ indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T1*>
+ constexpr I
+ ranges::replace(I first, S last, const T1& old_value, const T2& new_value, Proj proj = {}); // since C++20
+
+ template<input_range R, class T1, class T2, class Proj = identity>
+ requires indirectly_writable<iterator_t<R>, const T2&> &&
+ indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T1*>
+ constexpr borrowed_iterator_t<R>
+ ranges::replace(R&& r, const T1& old_value, const T2& new_value, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class T, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ requires indirectly_writable<I, const T&>
+ constexpr I ranges::replace_if(I first, S last, Pred pred, const T& new_value, Proj proj = {}); // since C++20
+
+ template<input_range R, class T, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ requires indirectly_writable<iterator_t<R>, const T&>
+ constexpr borrowed_iterator_t<R>
+ ranges::replace_if(R&& r, Pred pred, const T& new_value, Proj proj = {}); // since C++20
+
+ template<class T, class Proj = identity,
+ indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
+ constexpr const T&
+ ranges::clamp(const T& v, const T& lo, const T& hi, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ class Proj1 = identity, class Proj2 = identity,
+ indirect_strict_weak_order<projected<I1, Proj1>,
+ projected<I2, Proj2>> Comp = ranges::less>
+ constexpr bool
+ ranges::lexicographical_compare(I1 first1, S1 last1, I2 first2, S2 last2,
+ Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, input_range R2, class Proj1 = identity,
+ class Proj2 = identity,
+ indirect_strict_weak_order<projected<iterator_t<R1>, Proj1>,
+ projected<iterator_t<R2>, Proj2>> Comp = ranges::less>
+ constexpr bool
+ ranges::lexicographical_compare(R1&& r1, R2&& r2, Comp comp = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<bidirectional_iterator I1, sentinel_for<I1> S1, bidirectional_iterator I2>
+ requires indirectly_movable<I1, I2>
+ constexpr ranges::move_backward_result<I1, I2>
+ ranges::move_backward(I1 first, S1 last, I2 result); // since C++20
+
+ template<bidirectional_range R, bidirectional_iterator I>
+ requires indirectly_movable<iterator_t<R>, I>
+ constexpr ranges::move_backward_result<borrowed_iterator_t<R>, I>
+ ranges::move_backward(R&& r, I result); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, weakly_incrementable O>
+ requires indirectly_movable<I, O>
+ constexpr ranges::move_result<I, O>
+ ranges::move(I first, S last, O result); // since C++20
+
+ template<input_range R, weakly_incrementable O>
+ requires indirectly_movable<iterator_t<R>, O>
+ constexpr ranges::move_result<borrowed_iterator_t<R>, O>
+ ranges::move(R&& r, O result); // since C++20
+
+ template<class I, class O1, class O2>
+ using partition_copy_result = in_out_out_result<I, O1, O2>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S,
+ weakly_incrementable O1, weakly_incrementable O2,
+ class Proj = identity, indirect_unary_predicate<projected<I, Proj>> Pred>
+ requires indirectly_copyable<I, O1> && indirectly_copyable<I, O2>
+ constexpr partition_copy_result<I, O1, O2>
+ partition_copy(I first, S last, O1 out_true, O2 out_false, Pred pred,
+ Proj proj = {}); // since C++20
+
+ template<input_range R, weakly_incrementable O1, weakly_incrementable O2,
+ class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ requires indirectly_copyable<iterator_t<R>, O1> &&
+ indirectly_copyable<iterator_t<R>, O2>
+ constexpr partition_copy_result<borrowed_iterator_t<R>, O1, O2>
+ partition_copy(R&& r, O1 out_true, O2 out_false, Pred pred, Proj proj = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr I partition_point(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ constexpr borrowed_iterator_t<R>
+ partition_point(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<class I1, class I2, class O>
+ using merge_result = in_in_out_result<I1, I2, O>; // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ weakly_incrementable O, class Comp = ranges::less, class Proj1 = identity,
+ class Proj2 = identity>
+ requires mergeable<I1, I2, O, Comp, Proj1, Proj2>
+ constexpr merge_result<I1, I2, O>
+ merge(I1 first1, S1 last1, I2 first2, S2 last2, O result,
+ Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, input_range R2, weakly_incrementable O, class Comp = ranges::less,
+ class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
+ constexpr merge_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>, O>
+ merge(R1&& r1, R2&& r2, O result,
+ Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<permutable I, sentinel_for<I> S, class T, class Proj = identity>
+ requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
+ constexpr subrange<I> ranges::remove(I first, S last, const T& value, Proj proj = {}); // since C++20
+
+ template<forward_range R, class T, class Proj = identity>
+ requires permutable<iterator_t<R>> &&
+ indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
+ constexpr borrowed_subrange_t<R>
+ ranges::remove(R&& r, const T& value, Proj proj = {}); // since C++20
+
+ template<permutable I, sentinel_for<I> S, class Proj = identity,
+ indirect_unary_predicate<projected<I, Proj>> Pred>
+ constexpr subrange<I> ranges::remove_if(I first, S last, Pred pred, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ requires permutable<iterator_t<R>>
+ constexpr borrowed_subrange_t<R>
+ ranges::remove_if(R&& r, Pred pred, Proj proj = {}); // since C++20
+
+ template<class I, class O>
+ using set_difference_result = in_out_result<I, O>; // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ weakly_incrementable O, class Comp = ranges::less,
+ class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<I1, I2, O, Comp, Proj1, Proj2>
+ constexpr set_difference_result<I1, O>
+ set_difference(I1 first1, S1 last1, I2 first2, S2 last2, O result,
+ Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, input_range R2, weakly_incrementable O,
+ class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
+ constexpr set_difference_result<borrowed_iterator_t<R1>, O>
+ set_difference(R1&& r1, R2&& r2, O result,
+ Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<class I1, class I2, class O>
+ using set_intersection_result = in_in_out_result<I1, I2, O>; // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ weakly_incrementable O, class Comp = ranges::less,
+ class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<I1, I2, O, Comp, Proj1, Proj2>
+ constexpr set_intersection_result<I1, I2, O>
+ set_intersection(I1 first1, S1 last1, I2 first2, S2 last2, O result,
+ Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ weakly_incrementable O, class Comp = ranges::less,
+ class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<I1, I2, O, Comp, Proj1, Proj2>
+ constexpr set_intersection_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>, O>
+ set_intersection(R1&& r1, R2&& r2, O result,
+ Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template <class _InIter, class _OutIter>
+ using reverse_copy_result = in_out_result<_InIter, _OutIter>; // since C++20
+
+ template<bidirectional_iterator I, sentinel_for<I> S, weakly_incrementable O>
+ requires indirectly_copyable<I, O>
+ constexpr ranges::reverse_copy_result<I, O>
+ ranges::reverse_copy(I first, S last, O result); // since C++20
+
+ template<bidirectional_range R, weakly_incrementable O>
+ requires indirectly_copyable<iterator_t<R>, O>
+ constexpr ranges::reverse_copy_result<borrowed_iterator_t<R>, O>
+ ranges::reverse_copy(R&& r, O result); // since C++20
+
+ template<permutable I, sentinel_for<I> S>
+ constexpr subrange<I> rotate(I first, I middle, S last); // since C++20
+
+ template<forward_range R>
+ requires permutable<iterator_t<R>>
+ constexpr borrowed_subrange_t<R> rotate(R&& r, iterator_t<R> middle); // since C++20
+
+ template <class _InIter, class _OutIter>
+ using rotate_copy_result = in_out_result<_InIter, _OutIter>; // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, weakly_incrementable O>
+ requires indirectly_copyable<I, O>
+ constexpr ranges::rotate_copy_result<I, O>
+ ranges::rotate_copy(I first, I middle, S last, O result); // since C++20
+
+ template<forward_range R, weakly_incrementable O>
+ requires indirectly_copyable<iterator_t<R>, O>
+ constexpr ranges::rotate_copy_result<borrowed_iterator_t<R>, O>
+ ranges::rotate_copy(R&& r, iterator_t<R> middle, O result); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, weakly_incrementable O, class Gen>
+ requires (forward_iterator<I> || random_access_iterator<O>) &&
+ indirectly_copyable<I, O> &&
+ uniform_random_bit_generator<remove_reference_t<Gen>>
+ O sample(I first, S last, O out, iter_difference_t<I> n, Gen&& g); // since C++20
+
+ template<input_range R, weakly_incrementable O, class Gen>
+ requires (forward_range<R> || random_access_iterator<O>) &&
+ indirectly_copyable<iterator_t<R>, O> &&
+ uniform_random_bit_generator<remove_reference_t<Gen>>
+ O sample(R&& r, O out, range_difference_t<R> n, Gen&& g); // since C++20
+
+ template<random_access_iterator I, sentinel_for<I> S, class Gen>
+ requires permutable<I> &&
+ uniform_random_bit_generator<remove_reference_t<Gen>>
+ I shuffle(I first, S last, Gen&& g); // since C++20
+
+ template<random_access_range R, class Gen>
+ requires permutable<iterator_t<R>> &&
+ uniform_random_bit_generator<remove_reference_t<Gen>>
+ borrowed_iterator_t<R> shuffle(R&& r, Gen&& g); // since C++20
+
+ template<forward_iterator I1, sentinel_for<I1> S1, forward_iterator I2,
+ sentinel_for<I2> S2, class Proj1 = identity, class Proj2 = identity,
+ indirect_equivalence_relation<projected<I1, Proj1>,
+ projected<I2, Proj2>> Pred = ranges::equal_to>
+ constexpr bool ranges::is_permutation(I1 first1, S1 last1, I2 first2, S2 last2,
+ Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<forward_range R1, forward_range R2,
+ class Proj1 = identity, class Proj2 = identity,
+ indirect_equivalence_relation<projected<iterator_t<R1>, Proj1>,
+ projected<iterator_t<R2>, Proj2>> Pred = ranges::equal_to>
+ constexpr bool ranges::is_permutation(R1&& r1, R2&& r2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<forward_iterator I1, sentinel_for<I1> S1, forward_iterator I2,
+ sentinel_for<I2> S2, class Pred = ranges::equal_to,
+ class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+ constexpr subrange<I1>
+ ranges::search(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<forward_range R1, forward_range R2, class Pred = ranges::equal_to,
+ class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+ constexpr borrowed_subrange_t<R1>
+ ranges::search(R1&& r1, R2&& r2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class T,
+ class Pred = ranges::equal_to, class Proj = identity>
+ requires indirectly_comparable<I, const T*, Pred, Proj>
+ constexpr subrange<I>
+ ranges::search_n(I first, S last, iter_difference_t<I> count,
+ const T& value, Pred pred = {}, Proj proj = {}); // since C++20
+
+ template<forward_range R, class T, class Pred = ranges::equal_to,
+ class Proj = identity>
+ requires indirectly_comparable<iterator_t<R>, const T*, Pred, Proj>
+ constexpr borrowed_subrange_t<R>
+ ranges::search_n(R&& r, range_difference_t<R> count,
+ const T& value, Pred pred = {}, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class T,
+ indirectly-binary-left-foldable<T, I> F>
+ constexpr auto ranges::fold_left(I first, S last, T init, F f); // since C++23
+
+ template<input_range R, class T, indirectly-binary-left-foldable<T, iterator_t<R>> F>
+ constexpr auto fold_left(R&& r, T init, F f); // since C++23
+
+ template<class I, class T>
+ using fold_left_with_iter_result = in_value_result<I, T>; // since C++23
+
+ template<input_iterator I, sentinel_for<I> S, class T,
+ indirectly-binary-left-foldable<T, I> F>
+ constexpr see below fold_left_with_iter(I first, S last, T init, F f); // since C++23
+
+ template<input_range R, class T, indirectly-binary-left-foldable<T, iterator_t<R>> F>
+ constexpr see below fold_left_with_iter(R&& r, T init, F f); // since C++23
+
+ template<forward_iterator I1, sentinel_for<I1> S1, forward_iterator I2, sentinel_for<I2> S2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
+ constexpr subrange<I1>
+ ranges::find_end(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<forward_range R1, forward_range R2,
+ class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
+ requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
+ constexpr borrowed_subrange_t<R1>
+ ranges::find_end(R1&& r1, R2&& r2, Pred pred = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<class I1, class I2, class O>
+ using set_symmetric_difference_result = in_in_out_result<I1, I2, O>; // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ weakly_incrementable O, class Comp = ranges::less,
+ class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<I1, I2, O, Comp, Proj1, Proj2>
+ constexpr set_symmetric_difference_result<I1, I2, O>
+ set_symmetric_difference(I1 first1, S1 last1, I2 first2, S2 last2, O result,
+ Comp comp = {}, Proj1 proj1 = {},
+ Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, input_range R2, weakly_incrementable O,
+ class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
+ constexpr set_symmetric_difference_result<borrowed_iterator_t<R1>,
+ borrowed_iterator_t<R2>, O>
+ set_symmetric_difference(R1&& r1, R2&& r2, O result, Comp comp = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity,
+ indirect_strict_weak_order<const T*, projected<I, Proj>> Comp = ranges::less>
+ constexpr subrange<I>
+ equal_range(I first, S last, const T& value, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_range R, class T, class Proj = identity,
+ indirect_strict_weak_order<const T*, projected<iterator_t<R>, Proj>> Comp =
+ ranges::less>
+ constexpr borrowed_subrange_t<R>
+ equal_range(R&& r, const T& value, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<class I1, class I2, class O>
+ using set_union_result = in_in_out_result<I1, I2, O>; // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ weakly_incrementable O, class Comp = ranges::less,
+ class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<I1, I2, O, Comp, Proj1, Proj2>
+ constexpr set_union_result<I1, I2, O>
+ set_union(I1 first1, S1 last1, I2 first2, S2 last2, O result, Comp comp = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, input_range R2, weakly_incrementable O,
+ class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
+ requires mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
+ constexpr set_union_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>, O>
+ set_union(R1&& r1, R2&& r2, O result, Comp comp = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
+ class Proj1 = identity, class Proj2 = identity,
+ indirect_strict_weak_order<projected<I1, Proj1>, projected<I2, Proj2>> Comp =
+ ranges::less>
+ constexpr bool includes(I1 first1, S1 last1, I2 first2, S2 last2, Comp comp = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<input_range R1, input_range R2, class Proj1 = identity,
+ class Proj2 = identity,
+ indirect_strict_weak_order<projected<iterator_t<R1>, Proj1>,
+ projected<iterator_t<R2>, Proj2>> Comp = ranges::less>
+ constexpr bool includes(R1&& r1, R2&& r2, Comp comp = {},
+ Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++20
+
+ template<bidirectional_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ I inplace_merge(I first, I middle, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<bidirectional_range R, class Comp = ranges::less, class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ borrowed_iterator_t<R>
+ inplace_merge(R&& r, iterator_t<R> middle, Comp comp = {},
+ Proj proj = {}); // since C++20
+
+ template<permutable I, sentinel_for<I> S, class Proj = identity,
+ indirect_equivalence_relation<projected<I, Proj>> C = ranges::equal_to>
+ constexpr subrange<I> unique(I first, S last, C comp = {}, Proj proj = {}); // since C++20
+
+ template<forward_range R, class Proj = identity,
+ indirect_equivalence_relation<projected<iterator_t<R>, Proj>> C = ranges::equal_to>
+ requires permutable<iterator_t<R>>
+ constexpr borrowed_subrange_t<R>
+ unique(R&& r, C comp = {}, Proj proj = {}); // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, weakly_incrementable O, class Proj = identity,
+ indirect_equivalence_relation<projected<I, Proj>> C = ranges::equal_to>
+ requires indirectly_copyable<I, O> &&
+ (forward_iterator<I> ||
+ (input_iterator<O> && same_as<iter_value_t<I>, iter_value_t<O>>) ||
+ indirectly_copyable_storable<I, O>)
+ constexpr unique_copy_result<I, O>
+ unique_copy(I first, S last, O result, C comp = {}, Proj proj = {}); // since C++20
+
+ template<input_range R, weakly_incrementable O, class Proj = identity,
+ indirect_equivalence_relation<projected<iterator_t<R>, Proj>> C = ranges::equal_to>
+ requires indirectly_copyable<iterator_t<R>, O> &&
+ (forward_iterator<iterator_t<R>> ||
+ (input_iterator<O> && same_as<range_value_t<R>, iter_value_t<O>>) ||
+ indirectly_copyable_storable<iterator_t<R>, O>)
+ constexpr unique_copy_result<borrowed_iterator_t<R>, O>
+ unique_copy(R&& r, O result, C comp = {}, Proj proj = {}); // since C++20
+
+ template<class I, class O>
+ using remove_copy_result = in_out_result<I, O>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, weakly_incrementable O, class T,
+ class Proj = identity>
+ indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
+ constexpr remove_copy_result<I, O>
+ remove_copy(I first, S last, O result, const T& value, Proj proj = {}); // since C++20
+
+ template<input_range R, weakly_incrementable O, class T, class Proj = identity>
+ requires indirectly_copyable<iterator_t<R>, O> &&
+ indirect_binary_predicate<ranges::equal_to,
+ projected<iterator_t<R>, Proj>, const T*>
+ constexpr remove_copy_result<borrowed_iterator_t<R>, O>
+ remove_copy(R&& r, O result, const T& value, Proj proj = {}); // since C++20
+
+ template<class I, class O>
+ using remove_copy_if_result = in_out_result<I, O>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, weakly_incrementable O,
+ class Proj = identity, indirect_unary_predicate<projected<I, Proj>> Pred>
+ requires indirectly_copyable<I, O>
+ constexpr remove_copy_if_result<I, O>
+ remove_copy_if(I first, S last, O result, Pred pred, Proj proj = {}); // since C++20
+
+ template<input_range R, weakly_incrementable O, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ requires indirectly_copyable<iterator_t<R>, O>
+ constexpr remove_copy_if_result<borrowed_iterator_t<R>, O>
+ remove_copy_if(R&& r, O result, Pred pred, Proj proj = {}); // since C++20
+
+ template<class I, class O>
+ using replace_copy_result = in_out_result<I, O>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class T1, class T2,
+ output_iterator<const T2&> O, class Proj = identity>
+ requires indirectly_copyable<I, O> &&
+ indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T1*>
+ constexpr replace_copy_result<I, O>
+ replace_copy(I first, S last, O result, const T1& old_value, const T2& new_value,
+ Proj proj = {}); // since C++20
+
+ template<input_range R, class T1, class T2, output_iterator<const T2&> O,
+ class Proj = identity>
+ requires indirectly_copyable<iterator_t<R>, O> &&
+ indirect_binary_predicate<ranges::equal_to,
+ projected<iterator_t<R>, Proj>, const T1*>
+ constexpr replace_copy_result<borrowed_iterator_t<R>, O>
+ replace_copy(R&& r, O result, const T1& old_value, const T2& new_value,
+ Proj proj = {}); // since C++20
+
+ template<class I, class O>
+ using replace_copy_if_result = in_out_result<I, O>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class T, output_iterator<const T&> O,
+ class Proj = identity, indirect_unary_predicate<projected<I, Proj>> Pred>
+ requires indirectly_copyable<I, O>
+ constexpr replace_copy_if_result<I, O>
+ replace_copy_if(I first, S last, O result, Pred pred, const T& new_value,
+ Proj proj = {}); // since C++20
+
+ template<input_range R, class T, output_iterator<const T&> O, class Proj = identity,
+ indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
+ requires indirectly_copyable<iterator_t<R>, O>
+ constexpr replace_copy_if_result<borrowed_iterator_t<R>, O>
+ replace_copy_if(R&& r, O result, Pred pred, const T& new_value,
+ Proj proj = {}); // since C++20
+
+ template<class I>
+ using prev_permutation_result = in_found_result<I>; // since C++20
+
+ template<bidirectional_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr ranges::prev_permutation_result<I>
+ ranges::prev_permutation(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<bidirectional_range R, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr ranges::prev_permutation_result<borrowed_iterator_t<R>>
+ ranges::prev_permutation(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<class I>
+ using next_permutation_result = in_found_result<I>; // since C++20
+
+ template<bidirectional_iterator I, sentinel_for<I> S, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<I, Comp, Proj>
+ constexpr ranges::next_permutation_result<I>
+ ranges::next_permutation(I first, S last, Comp comp = {}, Proj proj = {}); // since C++20
+
+ template<bidirectional_range R, class Comp = ranges::less,
+ class Proj = identity>
+ requires sortable<iterator_t<R>, Comp, Proj>
+ constexpr ranges::next_permutation_result<borrowed_iterator_t<R>>
+ ranges::next_permutation(R&& r, Comp comp = {}, Proj proj = {}); // since C++20
+
+}
+
+template <class InputIterator, class Predicate>
+ constexpr bool // constexpr in C++20
+ all_of(InputIterator first, InputIterator last, Predicate pred);
+
+template <class InputIterator, class Predicate>
+ constexpr bool // constexpr in C++20
+ any_of(InputIterator first, InputIterator last, Predicate pred);
+
+template <class InputIterator, class Predicate>
+ constexpr bool // constexpr in C++20
+ none_of(InputIterator first, InputIterator last, Predicate pred);
+
+template <class InputIterator, class Function>
+ constexpr Function // constexpr in C++20
+ for_each(InputIterator first, InputIterator last, Function f);
+
+template<class InputIterator, class Size, class Function>
+ constexpr InputIterator // constexpr in C++20
+ for_each_n(InputIterator first, Size n, Function f); // C++17
+
+template <class InputIterator, class T>
+ constexpr InputIterator // constexpr in C++20
+ find(InputIterator first, InputIterator last, const T& value);
+
+template <class InputIterator, class Predicate>
+ constexpr InputIterator // constexpr in C++20
+ find_if(InputIterator first, InputIterator last, Predicate pred);
+
+template<class InputIterator, class Predicate>
+ constexpr InputIterator // constexpr in C++20
+ find_if_not(InputIterator first, InputIterator last, Predicate pred);
+
+template <class ForwardIterator1, class ForwardIterator2>
+ constexpr ForwardIterator1 // constexpr in C++20
+ find_end(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, ForwardIterator2 last2);
+
+template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
+ constexpr ForwardIterator1 // constexpr in C++20
+ find_end(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
+
+template <class ForwardIterator1, class ForwardIterator2>
+ constexpr ForwardIterator1 // constexpr in C++20
+ find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, ForwardIterator2 last2);
+
+template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
+ constexpr ForwardIterator1 // constexpr in C++20
+ find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
+
+template <class ForwardIterator>
+ constexpr ForwardIterator // constexpr in C++20
+ adjacent_find(ForwardIterator first, ForwardIterator last);
+
+template <class ForwardIterator, class BinaryPredicate>
+ constexpr ForwardIterator // constexpr in C++20
+ adjacent_find(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
+
+template <class InputIterator, class T>
+ constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
+ count(InputIterator first, InputIterator last, const T& value);
+
+template <class InputIterator, class Predicate>
+ constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
+ count_if(InputIterator first, InputIterator last, Predicate pred);
+
+template <class InputIterator1, class InputIterator2>
+ constexpr pair<InputIterator1, InputIterator2> // constexpr in C++20
+ mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
+
+template <class InputIterator1, class InputIterator2>
+ constexpr pair<InputIterator1, InputIterator2> // constexpr in C++20
+ mismatch(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2); // **C++14**
+
+template <class InputIterator1, class InputIterator2, class BinaryPredicate>
+ constexpr pair<InputIterator1, InputIterator2> // constexpr in C++20
+ mismatch(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, BinaryPredicate pred);
+
+template <class InputIterator1, class InputIterator2, class BinaryPredicate>
+ constexpr pair<InputIterator1, InputIterator2> // constexpr in C++20
+ mismatch(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2,
+ BinaryPredicate pred); // **C++14**
+
+template <class InputIterator1, class InputIterator2>
+ constexpr bool // constexpr in C++20
+ equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
+
+template <class InputIterator1, class InputIterator2>
+ constexpr bool // constexpr in C++20
+ equal(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2); // **C++14**
+
+template <class InputIterator1, class InputIterator2, class BinaryPredicate>
+ constexpr bool // constexpr in C++20
+ equal(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, BinaryPredicate pred);
+
+template <class InputIterator1, class InputIterator2, class BinaryPredicate>
+ constexpr bool // constexpr in C++20
+ equal(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2,
+ BinaryPredicate pred); // **C++14**
+
+template<class ForwardIterator1, class ForwardIterator2>
+ constexpr bool // constexpr in C++20
+ is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2);
+
+template<class ForwardIterator1, class ForwardIterator2>
+ constexpr bool // constexpr in C++20
+ is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
+
+template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
+ constexpr bool // constexpr in C++20
+ is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, BinaryPredicate pred);
+
+template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
+ constexpr bool // constexpr in C++20
+ is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, ForwardIterator2 last2,
+ BinaryPredicate pred); // **C++14**
+
+template <class ForwardIterator1, class ForwardIterator2>
+ constexpr ForwardIterator1 // constexpr in C++20
+ search(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, ForwardIterator2 last2);
+
+template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
+ constexpr ForwardIterator1 // constexpr in C++20
+ search(ForwardIterator1 first1, ForwardIterator1 last1,
+ ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
+
+template <class ForwardIterator, class Size, class T>
+ constexpr ForwardIterator // constexpr in C++20
+ search_n(ForwardIterator first, ForwardIterator last, Size count, const T& value);
+
+template <class ForwardIterator, class Size, class T, class BinaryPredicate>
+ constexpr ForwardIterator // constexpr in C++20
+ search_n(ForwardIterator first, ForwardIterator last,
+ Size count, const T& value, BinaryPredicate pred);
+
+template <class InputIterator, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ copy(InputIterator first, InputIterator last, OutputIterator result);
+
+template<class InputIterator, class OutputIterator, class Predicate>
+ constexpr OutputIterator // constexpr in C++20
+ copy_if(InputIterator first, InputIterator last,
+ OutputIterator result, Predicate pred);
+
+template<class InputIterator, class Size, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ copy_n(InputIterator first, Size n, OutputIterator result);
+
+template <class BidirectionalIterator1, class BidirectionalIterator2>
+ constexpr BidirectionalIterator2 // constexpr in C++20
+ copy_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
+ BidirectionalIterator2 result);
+
+// [alg.move], move
+template<class InputIterator, class OutputIterator>
+ constexpr OutputIterator move(InputIterator first, InputIterator last,
+ OutputIterator result);
+
+template<class BidirectionalIterator1, class BidirectionalIterator2>
+ constexpr BidirectionalIterator2
+ move_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
+ BidirectionalIterator2 result);
+
+template <class ForwardIterator1, class ForwardIterator2>
+ constexpr ForwardIterator2 // constexpr in C++20
+ swap_ranges(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2);
+
+namespace ranges {
+ template<class I1, class I2>
+ using swap_ranges_result = in_in_result<I1, I2>;
+
+template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2>
+ requires indirectly_swappable<I1, I2>
+ constexpr ranges::swap_ranges_result<I1, I2>
+ swap_ranges(I1 first1, S1 last1, I2 first2, S2 last2);
+
+template<input_range R1, input_range R2>
+ requires indirectly_swappable<iterator_t<R1>, iterator_t<R2>>
+ constexpr ranges::swap_ranges_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>>
+ swap_ranges(R1&& r1, R2&& r2);
+}
+
+template <class ForwardIterator1, class ForwardIterator2>
+ constexpr void // constexpr in C++20
+ iter_swap(ForwardIterator1 a, ForwardIterator2 b);
+
+template <class InputIterator, class OutputIterator, class UnaryOperation>
+ constexpr OutputIterator // constexpr in C++20
+ transform(InputIterator first, InputIterator last, OutputIterator result, UnaryOperation op);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator, class BinaryOperation>
+ constexpr OutputIterator // constexpr in C++20
+ transform(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2,
+ OutputIterator result, BinaryOperation binary_op);
+
+template <class ForwardIterator, class T>
+ constexpr void // constexpr in C++20
+ replace(ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value);
+
+template <class ForwardIterator, class Predicate, class T>
+ constexpr void // constexpr in C++20
+ replace_if(ForwardIterator first, ForwardIterator last, Predicate pred, const T& new_value);
+
+template <class InputIterator, class OutputIterator, class T>
+ constexpr OutputIterator // constexpr in C++20
+ replace_copy(InputIterator first, InputIterator last, OutputIterator result,
+ const T& old_value, const T& new_value);
+
+template <class InputIterator, class OutputIterator, class Predicate, class T>
+ constexpr OutputIterator // constexpr in C++20
+ replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T& new_value);
+
+template <class ForwardIterator, class T>
+ constexpr void // constexpr in C++20
+ fill(ForwardIterator first, ForwardIterator last, const T& value);
+
+template <class OutputIterator, class Size, class T>
+ constexpr OutputIterator // constexpr in C++20
+ fill_n(OutputIterator first, Size n, const T& value);
+
+template <class ForwardIterator, class Generator>
+ constexpr void // constexpr in C++20
+ generate(ForwardIterator first, ForwardIterator last, Generator gen);
+
+template <class OutputIterator, class Size, class Generator>
+ constexpr OutputIterator // constexpr in C++20
+ generate_n(OutputIterator first, Size n, Generator gen);
+
+template <class ForwardIterator, class T>
+ constexpr ForwardIterator // constexpr in C++20
+ remove(ForwardIterator first, ForwardIterator last, const T& value);
+
+template <class ForwardIterator, class Predicate>
+ constexpr ForwardIterator // constexpr in C++20
+ remove_if(ForwardIterator first, ForwardIterator last, Predicate pred);
+
+template <class InputIterator, class OutputIterator, class T>
+ constexpr OutputIterator // constexpr in C++20
+ remove_copy(InputIterator first, InputIterator last, OutputIterator result, const T& value);
+
+template <class InputIterator, class OutputIterator, class Predicate>
+ constexpr OutputIterator // constexpr in C++20
+ remove_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred);
+
+template <class ForwardIterator>
+ constexpr ForwardIterator // constexpr in C++20
+ unique(ForwardIterator first, ForwardIterator last);
+
+template <class ForwardIterator, class BinaryPredicate>
+ constexpr ForwardIterator // constexpr in C++20
+ unique(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
+
+template <class InputIterator, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ unique_copy(InputIterator first, InputIterator last, OutputIterator result);
+
+template <class InputIterator, class OutputIterator, class BinaryPredicate>
+ constexpr OutputIterator // constexpr in C++20
+ unique_copy(InputIterator first, InputIterator last, OutputIterator result, BinaryPredicate pred);
+
+template <class BidirectionalIterator>
+ constexpr void // constexpr in C++20
+ reverse(BidirectionalIterator first, BidirectionalIterator last);
+
+template <class BidirectionalIterator, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ reverse_copy(BidirectionalIterator first, BidirectionalIterator last, OutputIterator result);
+
+template <class ForwardIterator>
+ constexpr ForwardIterator // constexpr in C++20
+ rotate(ForwardIterator first, ForwardIterator middle, ForwardIterator last);
+
+template <class ForwardIterator, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ rotate_copy(ForwardIterator first, ForwardIterator middle, ForwardIterator last, OutputIterator result);
+
+template <class RandomAccessIterator>
+ void
+ random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14, removed in C++17
+
+template <class RandomAccessIterator, class RandomNumberGenerator>
+ void
+ random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
+ RandomNumberGenerator& rand); // deprecated in C++14, removed in C++17
+
+template<class PopulationIterator, class SampleIterator,
+ class Distance, class UniformRandomBitGenerator>
+ SampleIterator sample(PopulationIterator first, PopulationIterator last,
+ SampleIterator out, Distance n,
+ UniformRandomBitGenerator&& g); // C++17
+
+template<class RandomAccessIterator, class UniformRandomNumberGenerator>
+ void shuffle(RandomAccessIterator first, RandomAccessIterator last,
+ UniformRandomNumberGenerator&& g);
+
+template<class ForwardIterator>
+ constexpr ForwardIterator
+ shift_left(ForwardIterator first, ForwardIterator last,
+ typename iterator_traits<ForwardIterator>::difference_type n); // C++20
+
+template<class ForwardIterator>
+ constexpr ForwardIterator
+ shift_right(ForwardIterator first, ForwardIterator last,
+ typename iterator_traits<ForwardIterator>::difference_type n); // C++20
+
+template <class InputIterator, class Predicate>
+ constexpr bool // constexpr in C++20
+ is_partitioned(InputIterator first, InputIterator last, Predicate pred);
+
+template <class ForwardIterator, class Predicate>
+ constexpr ForwardIterator // constexpr in C++20
+ partition(ForwardIterator first, ForwardIterator last, Predicate pred);
+
+template <class InputIterator, class OutputIterator1,
+ class OutputIterator2, class Predicate>
+ constexpr pair<OutputIterator1, OutputIterator2> // constexpr in C++20
+ partition_copy(InputIterator first, InputIterator last,
+ OutputIterator1 out_true, OutputIterator2 out_false,
+ Predicate pred);
+
+template <class ForwardIterator, class Predicate>
+ ForwardIterator
+ stable_partition(ForwardIterator first, ForwardIterator last, Predicate pred);
+
+template<class ForwardIterator, class Predicate>
+ constexpr ForwardIterator // constexpr in C++20
+ partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
+
+template <class ForwardIterator>
+ constexpr bool // constexpr in C++20
+ is_sorted(ForwardIterator first, ForwardIterator last);
+
+template <class ForwardIterator, class Compare>
+ constexpr bool // constexpr in C++20
+ is_sorted(ForwardIterator first, ForwardIterator last, Compare comp);
+
+template<class ForwardIterator>
+ constexpr ForwardIterator // constexpr in C++20
+ is_sorted_until(ForwardIterator first, ForwardIterator last);
+
+template <class ForwardIterator, class Compare>
+ constexpr ForwardIterator // constexpr in C++20
+ is_sorted_until(ForwardIterator first, ForwardIterator last, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr void // constexpr in C++20
+ sort(RandomAccessIterator first, RandomAccessIterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr void // constexpr in C++20
+ sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
+
+template <class RandomAccessIterator>
+ void
+ stable_sort(RandomAccessIterator first, RandomAccessIterator last);
+
+template <class RandomAccessIterator, class Compare>
+ void
+ stable_sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr void // constexpr in C++20
+ partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr void // constexpr in C++20
+ partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last, Compare comp);
+
+template <class InputIterator, class RandomAccessIterator>
+ constexpr RandomAccessIterator // constexpr in C++20
+ partial_sort_copy(InputIterator first, InputIterator last,
+ RandomAccessIterator result_first, RandomAccessIterator result_last);
+
+template <class InputIterator, class RandomAccessIterator, class Compare>
+ constexpr RandomAccessIterator // constexpr in C++20
+ partial_sort_copy(InputIterator first, InputIterator last,
+ RandomAccessIterator result_first, RandomAccessIterator result_last, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr void // constexpr in C++20
+ nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr void // constexpr in C++20
+ nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last, Compare comp);
+
+template <class ForwardIterator, class T>
+ constexpr ForwardIterator // constexpr in C++20
+ lower_bound(ForwardIterator first, ForwardIterator last, const T& value);
+
+template <class ForwardIterator, class T, class Compare>
+ constexpr ForwardIterator // constexpr in C++20
+ lower_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
+
+template <class ForwardIterator, class T>
+ constexpr ForwardIterator // constexpr in C++20
+ upper_bound(ForwardIterator first, ForwardIterator last, const T& value);
+
+template <class ForwardIterator, class T, class Compare>
+ constexpr ForwardIterator // constexpr in C++20
+ upper_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
+
+template <class ForwardIterator, class T>
+ constexpr pair<ForwardIterator, ForwardIterator> // constexpr in C++20
+ equal_range(ForwardIterator first, ForwardIterator last, const T& value);
+
+template <class ForwardIterator, class T, class Compare>
+ constexpr pair<ForwardIterator, ForwardIterator> // constexpr in C++20
+ equal_range(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
+
+template <class ForwardIterator, class T>
+ constexpr bool // constexpr in C++20
+ binary_search(ForwardIterator first, ForwardIterator last, const T& value);
+
+template <class ForwardIterator, class T, class Compare>
+ constexpr bool // constexpr in C++20
+ binary_search(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ merge(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
+ constexpr OutputIterator // constexpr in C++20
+ merge(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
+
+template <class BidirectionalIterator>
+ void
+ inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last);
+
+template <class BidirectionalIterator, class Compare>
+ void
+ inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last, Compare comp);
+
+template <class InputIterator1, class InputIterator2>
+ constexpr bool // constexpr in C++20
+ includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
+
+template <class InputIterator1, class InputIterator2, class Compare>
+ constexpr bool // constexpr in C++20
+ includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, Compare comp);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ set_union(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
+ constexpr OutputIterator // constexpr in C++20
+ set_union(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ set_intersection(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
+ constexpr OutputIterator // constexpr in C++20
+ set_intersection(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ set_difference(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
+ constexpr OutputIterator // constexpr in C++20
+ set_difference(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator>
+ constexpr OutputIterator // constexpr in C++20
+ set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result);
+
+template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
+ constexpr OutputIterator // constexpr in C++20
+ set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr void // constexpr in C++20
+ push_heap(RandomAccessIterator first, RandomAccessIterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr void // constexpr in C++20
+ push_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr void // constexpr in C++20
+ pop_heap(RandomAccessIterator first, RandomAccessIterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr void // constexpr in C++20
+ pop_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr void // constexpr in C++20
+ make_heap(RandomAccessIterator first, RandomAccessIterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr void // constexpr in C++20
+ make_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr void // constexpr in C++20
+ sort_heap(RandomAccessIterator first, RandomAccessIterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr void // constexpr in C++20
+ sort_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr bool // constexpr in C++20
+ is_heap(RandomAccessIterator first, RandomAccessiterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr bool // constexpr in C++20
+ is_heap(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
+
+template <class RandomAccessIterator>
+ constexpr RandomAccessIterator // constexpr in C++20
+ is_heap_until(RandomAccessIterator first, RandomAccessiterator last);
+
+template <class RandomAccessIterator, class Compare>
+ constexpr RandomAccessIterator // constexpr in C++20
+ is_heap_until(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
+
+template <class ForwardIterator>
+ constexpr ForwardIterator // constexpr in C++14
+ min_element(ForwardIterator first, ForwardIterator last);
+
+template <class ForwardIterator, class Compare>
+ constexpr ForwardIterator // constexpr in C++14
+ min_element(ForwardIterator first, ForwardIterator last, Compare comp);
+
+template <class T>
+ constexpr const T& // constexpr in C++14
+ min(const T& a, const T& b);
+
+template <class T, class Compare>
+ constexpr const T& // constexpr in C++14
+ min(const T& a, const T& b, Compare comp);
+
+template<class T>
+ constexpr T // constexpr in C++14
+ min(initializer_list<T> t);
+
+template<class T, class Compare>
+ constexpr T // constexpr in C++14
+ min(initializer_list<T> t, Compare comp);
+
+template<class T>
+ constexpr const T& clamp(const T& v, const T& lo, const T& hi); // C++17
+
+template<class T, class Compare>
+ constexpr const T& clamp(const T& v, const T& lo, const T& hi, Compare comp); // C++17
+
+template <class ForwardIterator>
+ constexpr ForwardIterator // constexpr in C++14
+ max_element(ForwardIterator first, ForwardIterator last);
+
+template <class ForwardIterator, class Compare>
+ constexpr ForwardIterator // constexpr in C++14
+ max_element(ForwardIterator first, ForwardIterator last, Compare comp);
+
+template <class T>
+ constexpr const T& // constexpr in C++14
+ max(const T& a, const T& b);
+
+template <class T, class Compare>
+ constexpr const T& // constexpr in C++14
+ max(const T& a, const T& b, Compare comp);
+
+template<class T>
+ constexpr T // constexpr in C++14
+ max(initializer_list<T> t);
+
+template<class T, class Compare>
+ constexpr T // constexpr in C++14
+ max(initializer_list<T> t, Compare comp);
+
+template<class ForwardIterator>
+ constexpr pair<ForwardIterator, ForwardIterator> // constexpr in C++14
+ minmax_element(ForwardIterator first, ForwardIterator last);
+
+template<class ForwardIterator, class Compare>
+ constexpr pair<ForwardIterator, ForwardIterator> // constexpr in C++14
+ minmax_element(ForwardIterator first, ForwardIterator last, Compare comp);
+
+template<class T>
+ constexpr pair<const T&, const T&> // constexpr in C++14
+ minmax(const T& a, const T& b);
+
+template<class T, class Compare>
+ constexpr pair<const T&, const T&> // constexpr in C++14
+ minmax(const T& a, const T& b, Compare comp);
+
+template<class T>
+ constexpr pair<T, T> // constexpr in C++14
+ minmax(initializer_list<T> t);
+
+template<class T, class Compare>
+ constexpr pair<T, T> // constexpr in C++14
+ minmax(initializer_list<T> t, Compare comp);
+
+template <class InputIterator1, class InputIterator2>
+ constexpr bool // constexpr in C++20
+ lexicographical_compare(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
+
+template <class InputIterator1, class InputIterator2, class Compare>
+ constexpr bool // constexpr in C++20
+ lexicographical_compare(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2, Compare comp);
+
+template<class InputIterator1, class InputIterator2, class Cmp>
+ constexpr auto
+ lexicographical_compare_three_way(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2,
+ Cmp comp)
+ -> decltype(comp(*b1, *b2)); // since C++20
+
+template<class InputIterator1, class InputIterator2>
+ constexpr auto
+ lexicographical_compare_three_way(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, InputIterator2 last2); // since C++20
+
+template <class BidirectionalIterator>
+ constexpr bool // constexpr in C++20
+ next_permutation(BidirectionalIterator first, BidirectionalIterator last);
+
+template <class BidirectionalIterator, class Compare>
+ constexpr bool // constexpr in C++20
+ next_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
+
+template <class BidirectionalIterator>
+ constexpr bool // constexpr in C++20
+ prev_permutation(BidirectionalIterator first, BidirectionalIterator last);
+
+template <class BidirectionalIterator, class Compare>
+ constexpr bool // constexpr in C++20
+ prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
+} // std
+
+*/
+
+#include <__config>
+
+#include <__algorithm/adjacent_find.h>
+#include <__algorithm/all_of.h>
+#include <__algorithm/any_of.h>
+#include <__algorithm/binary_search.h>
+#include <__algorithm/copy.h>
+#include <__algorithm/copy_backward.h>
+#include <__algorithm/copy_if.h>
+#include <__algorithm/copy_n.h>
+#include <__algorithm/count.h>
+#include <__algorithm/count_if.h>
+#include <__algorithm/equal.h>
+#include <__algorithm/equal_range.h>
+#include <__algorithm/fill.h>
+#include <__algorithm/fill_n.h>
+#include <__algorithm/find.h>
+#include <__algorithm/find_end.h>
+#include <__algorithm/find_first_of.h>
+#include <__algorithm/find_if.h>
+#include <__algorithm/find_if_not.h>
+#include <__algorithm/for_each.h>
+#include <__algorithm/generate.h>
+#include <__algorithm/generate_n.h>
+#include <__algorithm/includes.h>
+#include <__algorithm/inplace_merge.h>
+#include <__algorithm/is_heap.h>
+#include <__algorithm/is_heap_until.h>
+#include <__algorithm/is_partitioned.h>
+#include <__algorithm/is_permutation.h>
+#include <__algorithm/is_sorted.h>
+#include <__algorithm/is_sorted_until.h>
+#include <__algorithm/iter_swap.h>
+#include <__algorithm/lexicographical_compare.h>
+#include <__algorithm/lower_bound.h>
+#include <__algorithm/make_heap.h>
+#include <__algorithm/max.h>
+#include <__algorithm/max_element.h>
+#include <__algorithm/merge.h>
+#include <__algorithm/min.h>
+#include <__algorithm/min_element.h>
+#include <__algorithm/minmax.h>
+#include <__algorithm/minmax_element.h>
+#include <__algorithm/mismatch.h>
+#include <__algorithm/move.h>
+#include <__algorithm/move_backward.h>
+#include <__algorithm/next_permutation.h>
+#include <__algorithm/none_of.h>
+#include <__algorithm/nth_element.h>
+#include <__algorithm/partial_sort.h>
+#include <__algorithm/partial_sort_copy.h>
+#include <__algorithm/partition.h>
+#include <__algorithm/partition_copy.h>
+#include <__algorithm/partition_point.h>
+#include <__algorithm/pop_heap.h>
+#include <__algorithm/prev_permutation.h>
+#include <__algorithm/push_heap.h>
+#include <__algorithm/remove.h>
+#include <__algorithm/remove_copy.h>
+#include <__algorithm/remove_copy_if.h>
+#include <__algorithm/remove_if.h>
+#include <__algorithm/replace.h>
+#include <__algorithm/replace_copy.h>
+#include <__algorithm/replace_copy_if.h>
+#include <__algorithm/replace_if.h>
+#include <__algorithm/reverse.h>
+#include <__algorithm/reverse_copy.h>
+#include <__algorithm/rotate.h>
+#include <__algorithm/rotate_copy.h>
+#include <__algorithm/search.h>
+#include <__algorithm/search_n.h>
+#include <__algorithm/set_difference.h>
+#include <__algorithm/set_intersection.h>
+#include <__algorithm/set_symmetric_difference.h>
+#include <__algorithm/set_union.h>
+#include <__algorithm/shuffle.h>
+#include <__algorithm/sort.h>
+#include <__algorithm/sort_heap.h>
+#include <__algorithm/stable_partition.h>
+#include <__algorithm/stable_sort.h>
+#include <__algorithm/swap_ranges.h>
+#include <__algorithm/transform.h>
+#include <__algorithm/unique.h>
+#include <__algorithm/unique_copy.h>
+#include <__algorithm/upper_bound.h>
+
+#if _LIBCPP_STD_VER >= 17
+# include <__algorithm/clamp.h>
+# include <__algorithm/for_each_n.h>
+# include <__algorithm/pstl.h>
+# include <__algorithm/sample.h>
+#endif // _LIBCPP_STD_VER >= 17
+
+#if _LIBCPP_STD_VER >= 20
+# include <__algorithm/in_found_result.h>
+# include <__algorithm/in_fun_result.h>
+# include <__algorithm/in_in_out_result.h>
+# include <__algorithm/in_in_result.h>
+# include <__algorithm/in_out_out_result.h>
+# include <__algorithm/in_out_result.h>
+# include <__algorithm/lexicographical_compare_three_way.h>
+# include <__algorithm/min_max_result.h>
+# include <__algorithm/ranges_adjacent_find.h>
+# include <__algorithm/ranges_all_of.h>
+# include <__algorithm/ranges_any_of.h>
+# include <__algorithm/ranges_binary_search.h>
+# include <__algorithm/ranges_clamp.h>
+# include <__algorithm/ranges_contains.h>
+# include <__algorithm/ranges_copy.h>
+# include <__algorithm/ranges_copy_backward.h>
+# include <__algorithm/ranges_copy_if.h>
+# include <__algorithm/ranges_copy_n.h>
+# include <__algorithm/ranges_count.h>
+# include <__algorithm/ranges_count_if.h>
+# include <__algorithm/ranges_equal.h>
+# include <__algorithm/ranges_equal_range.h>
+# include <__algorithm/ranges_fill.h>
+# include <__algorithm/ranges_fill_n.h>
+# include <__algorithm/ranges_find.h>
+# include <__algorithm/ranges_find_end.h>
+# include <__algorithm/ranges_find_first_of.h>
+# include <__algorithm/ranges_find_if.h>
+# include <__algorithm/ranges_find_if_not.h>
+# include <__algorithm/ranges_for_each.h>
+# include <__algorithm/ranges_for_each_n.h>
+# include <__algorithm/ranges_generate.h>
+# include <__algorithm/ranges_generate_n.h>
+# include <__algorithm/ranges_includes.h>
+# include <__algorithm/ranges_inplace_merge.h>
+# include <__algorithm/ranges_is_heap.h>
+# include <__algorithm/ranges_is_heap_until.h>
+# include <__algorithm/ranges_is_partitioned.h>
+# include <__algorithm/ranges_is_permutation.h>
+# include <__algorithm/ranges_is_sorted.h>
+# include <__algorithm/ranges_is_sorted_until.h>
+# include <__algorithm/ranges_lexicographical_compare.h>
+# include <__algorithm/ranges_lower_bound.h>
+# include <__algorithm/ranges_make_heap.h>
+# include <__algorithm/ranges_max.h>
+# include <__algorithm/ranges_max_element.h>
+# include <__algorithm/ranges_merge.h>
+# include <__algorithm/ranges_min.h>
+# include <__algorithm/ranges_min_element.h>
+# include <__algorithm/ranges_minmax.h>
+# include <__algorithm/ranges_minmax_element.h>
+# include <__algorithm/ranges_mismatch.h>
+# include <__algorithm/ranges_move.h>
+# include <__algorithm/ranges_move_backward.h>
+# include <__algorithm/ranges_next_permutation.h>
+# include <__algorithm/ranges_none_of.h>
+# include <__algorithm/ranges_nth_element.h>
+# include <__algorithm/ranges_partial_sort.h>
+# include <__algorithm/ranges_partial_sort_copy.h>
+# include <__algorithm/ranges_partition.h>
+# include <__algorithm/ranges_partition_copy.h>
+# include <__algorithm/ranges_partition_point.h>
+# include <__algorithm/ranges_pop_heap.h>
+# include <__algorithm/ranges_prev_permutation.h>
+# include <__algorithm/ranges_push_heap.h>
+# include <__algorithm/ranges_remove.h>
+# include <__algorithm/ranges_remove_copy.h>
+# include <__algorithm/ranges_remove_copy_if.h>
+# include <__algorithm/ranges_remove_if.h>
+# include <__algorithm/ranges_replace.h>
+# include <__algorithm/ranges_replace_copy.h>
+# include <__algorithm/ranges_replace_copy_if.h>
+# include <__algorithm/ranges_replace_if.h>
+# include <__algorithm/ranges_reverse.h>
+# include <__algorithm/ranges_reverse_copy.h>
+# include <__algorithm/ranges_rotate.h>
+# include <__algorithm/ranges_rotate_copy.h>
+# include <__algorithm/ranges_sample.h>
+# include <__algorithm/ranges_search.h>
+# include <__algorithm/ranges_search_n.h>
+# include <__algorithm/ranges_set_difference.h>
+# include <__algorithm/ranges_set_intersection.h>
+# include <__algorithm/ranges_set_symmetric_difference.h>
+# include <__algorithm/ranges_set_union.h>
+# include <__algorithm/ranges_shuffle.h>
+# include <__algorithm/ranges_sort.h>
+# include <__algorithm/ranges_sort_heap.h>
+# include <__algorithm/ranges_stable_partition.h>
+# include <__algorithm/ranges_stable_sort.h>
+# include <__algorithm/ranges_swap_ranges.h>
+# include <__algorithm/ranges_transform.h>
+# include <__algorithm/ranges_unique.h>
+# include <__algorithm/ranges_unique_copy.h>
+# include <__algorithm/ranges_upper_bound.h>
+# include <__algorithm/shift_left.h>
+# include <__algorithm/shift_right.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+# include <__algorithm/fold.h>
+# include <__algorithm/ranges_contains_subrange.h>
+# include <__algorithm/ranges_ends_with.h>
+# include <__algorithm/ranges_find_last.h>
+# include <__algorithm/ranges_starts_with.h>
+#endif // _LIBCPP_STD_VER >= 23
+
+#include <version>
+
+// standard-mandated includes
+
+// [algorithm.syn]
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER == 14
+# include <execution>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <bit>
+# include <concepts>
+# include <cstdlib>
+# include <cstring>
+# include <iterator>
+# include <memory>
+# include <stdexcept>
+# include <type_traits>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_ALGORITHM
diff --git a/libcxx/include/__cxx03/any b/libcxx/include/__cxx03/any
new file mode 100644
index 00000000000000..5def14dc87e6bf
--- /dev/null
+++ b/libcxx/include/__cxx03/any
@@ -0,0 +1,614 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_ANY
+#define _LIBCPP_ANY
+
+/*
+ any synopsis
+
+namespace std {
+
+ class bad_any_cast : public bad_cast
+ {
+ public:
+ virtual const char* what() const noexcept;
+ };
+
+ class any
+ {
+ public:
+
+ // 6.3.1 any construct/destruct
+ any() noexcept;
+
+ any(const any& other);
+ any(any&& other) noexcept;
+
+ template <class ValueType>
+ any(ValueType&& value);
+
+ ~any();
+
+ // 6.3.2 any assignments
+ any& operator=(const any& rhs);
+ any& operator=(any&& rhs) noexcept;
+
+ template <class ValueType>
+ any& operator=(ValueType&& rhs);
+
+ // 6.3.3 any modifiers
+ template <class ValueType, class... Args>
+ decay_t<ValueType>& emplace(Args&&... args);
+ template <class ValueType, class U, class... Args>
+ decay_t<ValueType>& emplace(initializer_list<U>, Args&&...);
+ void reset() noexcept;
+ void swap(any& rhs) noexcept;
+
+ // 6.3.4 any observers
+ bool has_value() const noexcept;
+ const type_info& type() const noexcept;
+ };
+
+ // 6.4 Non-member functions
+ void swap(any& x, any& y) noexcept;
+
+ template <class T, class ...Args>
+ any make_any(Args&& ...args);
+ template <class T, class U, class ...Args>
+ any make_any(initializer_list<U>, Args&& ...args);
+
+ template<class ValueType>
+ ValueType any_cast(const any& operand);
+ template<class ValueType>
+ ValueType any_cast(any& operand);
+ template<class ValueType>
+ ValueType any_cast(any&& operand);
+
+ template<class ValueType>
+ const ValueType* any_cast(const any* operand) noexcept;
+ template<class ValueType>
+ ValueType* any_cast(any* operand) noexcept;
+
+} // namespace std
+
+*/
+
+#include <__config>
+#include <__memory/allocator.h>
+#include <__memory/allocator_destructor.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/unique_ptr.h>
+#include <__type_traits/add_const.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/aligned_storage.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+#include <__utility/unreachable.h>
+#include <__verbose_abort>
+#include <initializer_list>
+#include <typeinfo>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+namespace std {
+class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_AVAILABILITY_BAD_ANY_CAST bad_any_cast : public bad_cast {
+public:
+ const char* what() const _NOEXCEPT override;
+};
+} // namespace std
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST void __throw_bad_any_cast() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw bad_any_cast();
+# else
+ _LIBCPP_VERBOSE_ABORT("bad_any_cast was thrown in -fno-exceptions mode");
+# endif
+}
+
+// Forward declarations
+class _LIBCPP_TEMPLATE_VIS any;
+
+template <class _ValueType>
+_LIBCPP_HIDE_FROM_ABI add_pointer_t<add_const_t<_ValueType>> any_cast(any const*) _NOEXCEPT;
+
+template <class _ValueType>
+_LIBCPP_HIDE_FROM_ABI add_pointer_t<_ValueType> any_cast(any*) _NOEXCEPT;
+
+namespace __any_imp {
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+using _Buffer = aligned_storage_t<3 * sizeof(void*), alignof(void*)>;
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+template <class _Tp>
+using _IsSmallObject =
+ integral_constant<bool,
+ sizeof(_Tp) <= sizeof(_Buffer) && alignof(_Buffer) % alignof(_Tp) == 0 &&
+ is_nothrow_move_constructible<_Tp>::value >;
+
+enum class _Action { _Destroy, _Copy, _Move, _Get, _TypeInfo };
+
+template <class _Tp>
+struct _SmallHandler;
+template <class _Tp>
+struct _LargeHandler;
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS __unique_typeinfo {
+ static constexpr int __id = 0;
+};
+template <class _Tp>
+constexpr int __unique_typeinfo<_Tp>::__id;
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI constexpr const void* __get_fallback_typeid() {
+ return &__unique_typeinfo<remove_cv_t<remove_reference_t<_Tp>>>::__id;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI bool __compare_typeid(type_info const* __id, const void* __fallback_id) {
+# if !defined(_LIBCPP_HAS_NO_RTTI)
+ if (__id && *__id == typeid(_Tp))
+ return true;
+# endif
+ return !__id && __fallback_id == __any_imp::__get_fallback_typeid<_Tp>();
+}
+
+template <class _Tp>
+using _Handler = conditional_t< _IsSmallObject<_Tp>::value, _SmallHandler<_Tp>, _LargeHandler<_Tp>>;
+
+} // namespace __any_imp
+
+class _LIBCPP_TEMPLATE_VIS any {
+public:
+ // construct/destruct
+ _LIBCPP_HIDE_FROM_ABI constexpr any() _NOEXCEPT : __h_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI any(any const& __other) : __h_(nullptr) {
+ if (__other.__h_)
+ __other.__call(_Action::_Copy, this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI any(any&& __other) _NOEXCEPT : __h_(nullptr) {
+ if (__other.__h_)
+ __other.__call(_Action::_Move, this);
+ }
+
+ template < class _ValueType,
+ class _Tp = decay_t<_ValueType>,
+ class = enable_if_t< !is_same<_Tp, any>::value && !__is_inplace_type<_ValueType>::value &&
+ is_copy_constructible<_Tp>::value> >
+ _LIBCPP_HIDE_FROM_ABI any(_ValueType&& __value);
+
+ template <class _ValueType,
+ class... _Args,
+ class _Tp = decay_t<_ValueType>,
+ class = enable_if_t< is_constructible<_Tp, _Args...>::value && is_copy_constructible<_Tp>::value > >
+ _LIBCPP_HIDE_FROM_ABI explicit any(in_place_type_t<_ValueType>, _Args&&... __args);
+
+ template <class _ValueType,
+ class _Up,
+ class... _Args,
+ class _Tp = decay_t<_ValueType>,
+ class = enable_if_t< is_constructible<_Tp, initializer_list<_Up>&, _Args...>::value &&
+ is_copy_constructible<_Tp>::value> >
+ _LIBCPP_HIDE_FROM_ABI explicit any(in_place_type_t<_ValueType>, initializer_list<_Up>, _Args&&... __args);
+
+ _LIBCPP_HIDE_FROM_ABI ~any() { this->reset(); }
+
+ // assignments
+ _LIBCPP_HIDE_FROM_ABI any& operator=(any const& __rhs) {
+ any(__rhs).swap(*this);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI any& operator=(any&& __rhs) _NOEXCEPT {
+ any(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ template < class _ValueType,
+ class _Tp = decay_t<_ValueType>,
+ class = enable_if_t< !is_same<_Tp, any>::value && is_copy_constructible<_Tp>::value> >
+ _LIBCPP_HIDE_FROM_ABI any& operator=(_ValueType&& __rhs);
+
+ template <class _ValueType,
+ class... _Args,
+ class _Tp = decay_t<_ValueType>,
+ class = enable_if_t< is_constructible<_Tp, _Args...>::value && is_copy_constructible<_Tp>::value> >
+ _LIBCPP_HIDE_FROM_ABI _Tp& emplace(_Args&&...);
+
+ template <class _ValueType,
+ class _Up,
+ class... _Args,
+ class _Tp = decay_t<_ValueType>,
+ class = enable_if_t< is_constructible<_Tp, initializer_list<_Up>&, _Args...>::value &&
+ is_copy_constructible<_Tp>::value> >
+ _LIBCPP_HIDE_FROM_ABI _Tp& emplace(initializer_list<_Up>, _Args&&...);
+
+ // 6.3.3 any modifiers
+ _LIBCPP_HIDE_FROM_ABI void reset() _NOEXCEPT {
+ if (__h_)
+ this->__call(_Action::_Destroy);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(any& __rhs) _NOEXCEPT;
+
+ // 6.3.4 any observers
+ _LIBCPP_HIDE_FROM_ABI bool has_value() const _NOEXCEPT { return __h_ != nullptr; }
+
+# if !defined(_LIBCPP_HAS_NO_RTTI)
+ _LIBCPP_HIDE_FROM_ABI const type_info& type() const _NOEXCEPT {
+ if (__h_) {
+ return *static_cast<type_info const*>(this->__call(_Action::_TypeInfo));
+ } else {
+ return typeid(void);
+ }
+ }
+# endif
+
+private:
+ typedef __any_imp::_Action _Action;
+ using _HandleFuncPtr = void* (*)(_Action, any const*, any*, const type_info*, const void* __fallback_info);
+
+ union _Storage {
+ _LIBCPP_HIDE_FROM_ABI constexpr _Storage() : __ptr(nullptr) {}
+ void* __ptr;
+ __any_imp::_Buffer __buf;
+ };
+
+ _LIBCPP_HIDE_FROM_ABI void*
+ __call(_Action __a, any* __other = nullptr, type_info const* __info = nullptr, const void* __fallback_info = nullptr)
+ const {
+ return __h_(__a, this, __other, __info, __fallback_info);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void* __call(
+ _Action __a, any* __other = nullptr, type_info const* __info = nullptr, const void* __fallback_info = nullptr) {
+ return __h_(__a, this, __other, __info, __fallback_info);
+ }
+
+ template <class>
+ friend struct __any_imp::_SmallHandler;
+ template <class>
+ friend struct __any_imp::_LargeHandler;
+
+ template <class _ValueType>
+ friend add_pointer_t<add_const_t<_ValueType>> any_cast(any const*) _NOEXCEPT;
+
+ template <class _ValueType>
+ friend add_pointer_t<_ValueType> any_cast(any*) _NOEXCEPT;
+
+ _HandleFuncPtr __h_ = nullptr;
+ _Storage __s_;
+};
+
+namespace __any_imp {
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS _SmallHandler {
+ _LIBCPP_HIDE_FROM_ABI static void*
+ __handle(_Action __act, any const* __this, any* __other, type_info const* __info, const void* __fallback_info) {
+ switch (__act) {
+ case _Action::_Destroy:
+ __destroy(const_cast<any&>(*__this));
+ return nullptr;
+ case _Action::_Copy:
+ __copy(*__this, *__other);
+ return nullptr;
+ case _Action::_Move:
+ __move(const_cast<any&>(*__this), *__other);
+ return nullptr;
+ case _Action::_Get:
+ return __get(const_cast<any&>(*__this), __info, __fallback_info);
+ case _Action::_TypeInfo:
+ return __type_info();
+ }
+ __libcpp_unreachable();
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI static _Tp& __create(any& __dest, _Args&&... __args) {
+ typedef allocator<_Tp> _Alloc;
+ typedef allocator_traits<_Alloc> _ATraits;
+ _Alloc __a;
+ _Tp* __ret = static_cast<_Tp*>(static_cast<void*>(&__dest.__s_.__buf));
+ _ATraits::construct(__a, __ret, std::forward<_Args>(__args)...);
+ __dest.__h_ = &_SmallHandler::__handle;
+ return *__ret;
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI static void __destroy(any& __this) {
+ typedef allocator<_Tp> _Alloc;
+ typedef allocator_traits<_Alloc> _ATraits;
+ _Alloc __a;
+ _Tp* __p = static_cast<_Tp*>(static_cast<void*>(&__this.__s_.__buf));
+ _ATraits::destroy(__a, __p);
+ __this.__h_ = nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void __copy(any const& __this, any& __dest) {
+ _SmallHandler::__create(__dest, *static_cast<_Tp const*>(static_cast<void const*>(&__this.__s_.__buf)));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void __move(any& __this, any& __dest) {
+ _SmallHandler::__create(__dest, std::move(*static_cast<_Tp*>(static_cast<void*>(&__this.__s_.__buf))));
+ __destroy(__this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void* __get(any& __this, type_info const* __info, const void* __fallback_id) {
+ if (__any_imp::__compare_typeid<_Tp>(__info, __fallback_id))
+ return static_cast<void*>(&__this.__s_.__buf);
+ return nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void* __type_info() {
+# if !defined(_LIBCPP_HAS_NO_RTTI)
+ return const_cast<void*>(static_cast<void const*>(&typeid(_Tp)));
+# else
+ return nullptr;
+# endif
+ }
+};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS _LargeHandler {
+ _LIBCPP_HIDE_FROM_ABI static void*
+ __handle(_Action __act, any const* __this, any* __other, type_info const* __info, void const* __fallback_info) {
+ switch (__act) {
+ case _Action::_Destroy:
+ __destroy(const_cast<any&>(*__this));
+ return nullptr;
+ case _Action::_Copy:
+ __copy(*__this, *__other);
+ return nullptr;
+ case _Action::_Move:
+ __move(const_cast<any&>(*__this), *__other);
+ return nullptr;
+ case _Action::_Get:
+ return __get(const_cast<any&>(*__this), __info, __fallback_info);
+ case _Action::_TypeInfo:
+ return __type_info();
+ }
+ __libcpp_unreachable();
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI static _Tp& __create(any& __dest, _Args&&... __args) {
+ typedef allocator<_Tp> _Alloc;
+ typedef allocator_traits<_Alloc> _ATraits;
+ typedef __allocator_destructor<_Alloc> _Dp;
+ _Alloc __a;
+ unique_ptr<_Tp, _Dp> __hold(_ATraits::allocate(__a, 1), _Dp(__a, 1));
+ _Tp* __ret = __hold.get();
+ _ATraits::construct(__a, __ret, std::forward<_Args>(__args)...);
+ __dest.__s_.__ptr = __hold.release();
+ __dest.__h_ = &_LargeHandler::__handle;
+ return *__ret;
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI static void __destroy(any& __this) {
+ typedef allocator<_Tp> _Alloc;
+ typedef allocator_traits<_Alloc> _ATraits;
+ _Alloc __a;
+ _Tp* __p = static_cast<_Tp*>(__this.__s_.__ptr);
+ _ATraits::destroy(__a, __p);
+ _ATraits::deallocate(__a, __p, 1);
+ __this.__h_ = nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void __copy(any const& __this, any& __dest) {
+ _LargeHandler::__create(__dest, *static_cast<_Tp const*>(__this.__s_.__ptr));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void __move(any& __this, any& __dest) {
+ __dest.__s_.__ptr = __this.__s_.__ptr;
+ __dest.__h_ = &_LargeHandler::__handle;
+ __this.__h_ = nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void* __get(any& __this, type_info const* __info, void const* __fallback_info) {
+ if (__any_imp::__compare_typeid<_Tp>(__info, __fallback_info))
+ return static_cast<void*>(__this.__s_.__ptr);
+ return nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static void* __type_info() {
+# if !defined(_LIBCPP_HAS_NO_RTTI)
+ return const_cast<void*>(static_cast<void const*>(&typeid(_Tp)));
+# else
+ return nullptr;
+# endif
+ }
+};
+
+} // namespace __any_imp
+
+template <class _ValueType, class _Tp, class>
+any::any(_ValueType&& __v) : __h_(nullptr) {
+ __any_imp::_Handler<_Tp>::__create(*this, std::forward<_ValueType>(__v));
+}
+
+template <class _ValueType, class... _Args, class _Tp, class>
+any::any(in_place_type_t<_ValueType>, _Args&&... __args) {
+ __any_imp::_Handler<_Tp>::__create(*this, std::forward<_Args>(__args)...);
+}
+
+template <class _ValueType, class _Up, class... _Args, class _Tp, class>
+any::any(in_place_type_t<_ValueType>, initializer_list<_Up> __il, _Args&&... __args) {
+ __any_imp::_Handler<_Tp>::__create(*this, __il, std::forward<_Args>(__args)...);
+}
+
+template <class _ValueType, class, class>
+inline _LIBCPP_HIDE_FROM_ABI any& any::operator=(_ValueType&& __v) {
+ any(std::forward<_ValueType>(__v)).swap(*this);
+ return *this;
+}
+
+template <class _ValueType, class... _Args, class _Tp, class>
+inline _LIBCPP_HIDE_FROM_ABI _Tp& any::emplace(_Args&&... __args) {
+ reset();
+ return __any_imp::_Handler<_Tp>::__create(*this, std::forward<_Args>(__args)...);
+}
+
+template <class _ValueType, class _Up, class... _Args, class _Tp, class>
+inline _LIBCPP_HIDE_FROM_ABI _Tp& any::emplace(initializer_list<_Up> __il, _Args&&... __args) {
+ reset();
+ return __any_imp::_Handler<_Tp>::__create(*this, __il, std::forward<_Args>(__args)...);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void any::swap(any& __rhs) _NOEXCEPT {
+ if (this == &__rhs)
+ return;
+ if (__h_ && __rhs.__h_) {
+ any __tmp;
+ __rhs.__call(_Action::_Move, &__tmp);
+ this->__call(_Action::_Move, &__rhs);
+ __tmp.__call(_Action::_Move, this);
+ } else if (__h_) {
+ this->__call(_Action::_Move, &__rhs);
+ } else if (__rhs.__h_) {
+ __rhs.__call(_Action::_Move, this);
+ }
+}
+
+// 6.4 Non-member functions
+
+inline _LIBCPP_HIDE_FROM_ABI void swap(any& __lhs, any& __rhs) _NOEXCEPT { __lhs.swap(__rhs); }
+
+template <class _Tp, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI any make_any(_Args&&... __args) {
+ return any(in_place_type<_Tp>, std::forward<_Args>(__args)...);
+}
+
+template <class _Tp, class _Up, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI any make_any(initializer_list<_Up> __il, _Args&&... __args) {
+ return any(in_place_type<_Tp>, __il, std::forward<_Args>(__args)...);
+}
+
+template <class _ValueType>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _ValueType any_cast(any const& __v) {
+ using _RawValueType = __remove_cvref_t<_ValueType>;
+ static_assert(is_constructible<_ValueType, _RawValueType const&>::value,
+ "ValueType is required to be a const lvalue reference "
+ "or a CopyConstructible type");
+ auto __tmp = std::any_cast<add_const_t<_RawValueType>>(&__v);
+ if (__tmp == nullptr)
+ __throw_bad_any_cast();
+ return static_cast<_ValueType>(*__tmp);
+}
+
+template <class _ValueType>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _ValueType any_cast(any& __v) {
+ using _RawValueType = __remove_cvref_t<_ValueType>;
+ static_assert(is_constructible<_ValueType, _RawValueType&>::value,
+ "ValueType is required to be an lvalue reference "
+ "or a CopyConstructible type");
+ auto __tmp = std::any_cast<_RawValueType>(&__v);
+ if (__tmp == nullptr)
+ __throw_bad_any_cast();
+ return static_cast<_ValueType>(*__tmp);
+}
+
+template <class _ValueType>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _ValueType any_cast(any&& __v) {
+ using _RawValueType = __remove_cvref_t<_ValueType>;
+ static_assert(is_constructible<_ValueType, _RawValueType>::value,
+ "ValueType is required to be an rvalue reference "
+ "or a CopyConstructible type");
+ auto __tmp = std::any_cast<_RawValueType>(&__v);
+ if (__tmp == nullptr)
+ __throw_bad_any_cast();
+ return static_cast<_ValueType>(std::move(*__tmp));
+}
+
+template <class _ValueType>
+inline _LIBCPP_HIDE_FROM_ABI add_pointer_t<add_const_t<_ValueType>> any_cast(any const* __any) _NOEXCEPT {
+ static_assert(!is_void_v<_ValueType>, "_ValueType may not be void.");
+ static_assert(!is_reference<_ValueType>::value, "_ValueType may not be a reference.");
+ return std::any_cast<_ValueType>(const_cast<any*>(__any));
+}
+
+template <class _RetType>
+inline _LIBCPP_HIDE_FROM_ABI _RetType __pointer_or_func_cast(void* __p, /*IsFunction*/ false_type) noexcept {
+ return static_cast<_RetType>(__p);
+}
+
+template <class _RetType>
+inline _LIBCPP_HIDE_FROM_ABI _RetType __pointer_or_func_cast(void*, /*IsFunction*/ true_type) noexcept {
+ return nullptr;
+}
+
+template <class _ValueType>
+_LIBCPP_HIDE_FROM_ABI add_pointer_t<_ValueType> any_cast(any* __any) _NOEXCEPT {
+ using __any_imp::_Action;
+ static_assert(!is_void_v<_ValueType>, "_ValueType may not be void.");
+ static_assert(!is_reference<_ValueType>::value, "_ValueType may not be a reference.");
+ typedef add_pointer_t<_ValueType> _ReturnType;
+ if (__any && __any->__h_) {
+ void* __p = __any->__call(
+ _Action::_Get,
+ nullptr,
+# if !defined(_LIBCPP_HAS_NO_RTTI)
+ &typeid(_ValueType),
+# else
+ nullptr,
+# endif
+ __any_imp::__get_fallback_typeid<_ValueType>());
+ return std::__pointer_or_func_cast<_ReturnType>(__p, is_function<_ValueType>{});
+ }
+ return nullptr;
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <chrono>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstdlib>
+# include <iosfwd>
+# include <iterator>
+# include <memory>
+# include <stdexcept>
+# include <type_traits>
+# include <variant>
+#endif
+
+#endif // _LIBCPP_ANY
diff --git a/libcxx/include/__cxx03/array b/libcxx/include/__cxx03/array
new file mode 100644
index 00000000000000..6ffde852f48027
--- /dev/null
+++ b/libcxx/include/__cxx03/array
@@ -0,0 +1,515 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_ARRAY
+#define _LIBCPP_ARRAY
+
+/*
+ array synopsis
+
+namespace std
+{
+template <class T, size_t N >
+struct array
+{
+ // types:
+ typedef T & reference;
+ typedef const T & const_reference;
+ typedef implementation defined iterator;
+ typedef implementation defined const_iterator;
+ typedef size_t size_type;
+ typedef ptrdiff_t difference_type;
+ typedef T value_type;
+ typedef T* pointer;
+ typedef const T* const_pointer;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+ // No explicit construct/copy/destroy for aggregate type
+ void fill(const T& u); // constexpr in C++20
+ void swap(array& a) noexcept(is_nothrow_swappable_v<T>); // constexpr in C++20
+
+ // iterators:
+ iterator begin() noexcept; // constexpr in C++17
+ const_iterator begin() const noexcept; // constexpr in C++17
+ iterator end() noexcept; // constexpr in C++17
+ const_iterator end() const noexcept; // constexpr in C++17
+
+ reverse_iterator rbegin() noexcept; // constexpr in C++17
+ const_reverse_iterator rbegin() const noexcept; // constexpr in C++17
+ reverse_iterator rend() noexcept; // constexpr in C++17
+ const_reverse_iterator rend() const noexcept; // constexpr in C++17
+
+ const_iterator cbegin() const noexcept; // constexpr in C++17
+ const_iterator cend() const noexcept; // constexpr in C++17
+ const_reverse_iterator crbegin() const noexcept; // constexpr in C++17
+ const_reverse_iterator crend() const noexcept; // constexpr in C++17
+
+ // capacity:
+ constexpr size_type size() const noexcept;
+ constexpr size_type max_size() const noexcept;
+ constexpr bool empty() const noexcept;
+
+ // element access:
+ reference operator[](size_type n); // constexpr in C++17
+ const_reference operator[](size_type n) const; // constexpr in C++14
+ reference at(size_type n); // constexpr in C++17
+ const_reference at(size_type n) const; // constexpr in C++14
+
+ reference front(); // constexpr in C++17
+ const_reference front() const; // constexpr in C++14
+ reference back(); // constexpr in C++17
+ const_reference back() const; // constexpr in C++14
+
+ T* data() noexcept; // constexpr in C++17
+ const T* data() const noexcept; // constexpr in C++17
+};
+
+template <class T, class... U>
+ array(T, U...) -> array<T, 1 + sizeof...(U)>; // C++17
+
+template <class T, size_t N>
+ bool operator==(const array<T,N>& x, const array<T,N>& y); // constexpr in C++20
+template <class T, size_t N>
+ bool operator!=(const array<T,N>& x, const array<T,N>& y); // removed in C++20
+template <class T, size_t N>
+ bool operator<(const array<T,N>& x, const array<T,N>& y); // removed in C++20
+template <class T, size_t N>
+ bool operator>(const array<T,N>& x, const array<T,N>& y); // removed in C++20
+template <class T, size_t N>
+ bool operator<=(const array<T,N>& x, const array<T,N>& y); // removed in C++20
+template <class T, size_t N>
+ bool operator>=(const array<T,N>& x, const array<T,N>& y); // removed in C++20
+template<class T, size_t N>
+ constexpr synth-three-way-result<T>
+ operator<=>(const array<T, N>& x, const array<T, N>& y); // since C++20
+
+template <class T, size_t N >
+ void swap(array<T,N>& x, array<T,N>& y) noexcept(noexcept(x.swap(y))); // constexpr in C++20
+
+template <class T, size_t N>
+ constexpr array<remove_cv_t<T>, N> to_array(T (&a)[N]); // C++20
+template <class T, size_t N>
+ constexpr array<remove_cv_t<T>, N> to_array(T (&&a)[N]); // C++20
+
+template <class T> struct tuple_size;
+template <size_t I, class T> struct tuple_element;
+template <class T, size_t N> struct tuple_size<array<T, N>>;
+template <size_t I, class T, size_t N> struct tuple_element<I, array<T, N>>;
+template <size_t I, class T, size_t N> T& get(array<T, N>&) noexcept; // constexpr in C++14
+template <size_t I, class T, size_t N> const T& get(const array<T, N>&) noexcept; // constexpr in C++14
+template <size_t I, class T, size_t N> T&& get(array<T, N>&&) noexcept; // constexpr in C++14
+template <size_t I, class T, size_t N> const T&& get(const array<T, N>&&) noexcept; // constexpr in C++14
+
+} // std
+
+*/
+
+#include <__algorithm/equal.h>
+#include <__algorithm/fill_n.h>
+#include <__algorithm/lexicographical_compare.h>
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__algorithm/swap_ranges.h>
+#include <__assert>
+#include <__config>
+#include <__fwd/array.h>
+#include <__iterator/reverse_iterator.h>
+#include <__iterator/wrap_iter.h>
+#include <__tuple/sfinae_helpers.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/remove_cv.h>
+#include <__utility/empty.h>
+#include <__utility/integer_sequence.h>
+#include <__utility/move.h>
+#include <__utility/unreachable.h>
+#include <stdexcept>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [array.syn]
+#include <compare>
+#include <initializer_list>
+
+// [tuple.helper]
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_size.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, size_t _Size>
+struct _LIBCPP_TEMPLATE_VIS array {
+ using __trivially_relocatable = __conditional_t<__libcpp_is_trivially_relocatable<_Tp>::value, array, void>;
+
+ // types:
+ using __self = array;
+ using value_type = _Tp;
+ using reference = value_type&;
+ using const_reference = const value_type&;
+ using pointer = value_type*;
+ using const_pointer = const value_type*;
+#if defined(_LIBCPP_ABI_USE_WRAP_ITER_IN_STD_ARRAY)
+ using iterator = __wrap_iter<pointer>;
+ using const_iterator = __wrap_iter<const_pointer>;
+#else
+ using iterator = pointer;
+ using const_iterator = const_pointer;
+#endif
+ using size_type = size_t;
+ using difference_type = ptrdiff_t;
+ using reverse_iterator = std::reverse_iterator<iterator>;
+ using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+
+ _Tp __elems_[_Size];
+
+ // No explicit construct/copy/destroy for aggregate type
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type& __u) {
+ std::fill_n(data(), _Size, __u);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array& __a) _NOEXCEPT_(__is_nothrow_swappable_v<_Tp>) {
+ std::swap_ranges(data(), data() + _Size, __a.data());
+ }
+
+ // iterators:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT { return iterator(data()); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
+ return const_iterator(data());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT { return iterator(data() + _Size); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
+ return const_iterator(data() + _Size);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
+ return reverse_iterator(end());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rbegin() const _NOEXCEPT {
+ return const_reverse_iterator(end());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
+ return reverse_iterator(begin());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
+ return const_reverse_iterator(begin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crbegin() const _NOEXCEPT {
+ return rbegin();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ // capacity:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return _Size; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return _Size; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return _Size == 0; }
+
+ // element access:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type __n) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
+ return __elems_[__n];
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference operator[](size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
+ return __elems_[__n];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type __n) {
+ if (__n >= _Size)
+ __throw_out_of_range("array::at");
+ return __elems_[__n];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type __n) const {
+ if (__n >= _Size)
+ __throw_out_of_range("array::at");
+ return __elems_[__n];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT { return (*this)[0]; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT { return (*this)[0]; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT { return (*this)[_Size - 1]; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
+ return (*this)[_Size - 1];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT { return __elems_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT { return __elems_; }
+};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS array<_Tp, 0> {
+ // types:
+ typedef array __self;
+ typedef _Tp value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef value_type* iterator;
+ typedef const value_type* const_iterator;
+ typedef value_type* pointer;
+ typedef const value_type* const_pointer;
+ typedef size_t size_type;
+ typedef ptrdiff_t difference_type;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+ typedef __conditional_t<is_const<_Tp>::value, const __empty, __empty> _EmptyType;
+
+ struct _ArrayInStructT {
+ _Tp __data_[1];
+ };
+ _ALIGNAS_TYPE(_ArrayInStructT) _EmptyType __elems_[sizeof(_ArrayInStructT)];
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT { return nullptr; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT { return nullptr; }
+
+ // No explicit construct/copy/destroy for aggregate type
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type&) {
+ static_assert(!is_const<_Tp>::value, "cannot fill zero-sized array of type 'const T'");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array&) _NOEXCEPT {
+ static_assert(!is_const<_Tp>::value, "cannot swap zero-sized array of type 'const T'");
+ }
+
+ // iterators:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT { return iterator(data()); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
+ return const_iterator(data());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT { return iterator(data()); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
+ return const_iterator(data());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
+ return reverse_iterator(end());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rbegin() const _NOEXCEPT {
+ return const_reverse_iterator(end());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
+ return reverse_iterator(begin());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
+ return const_reverse_iterator(begin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crbegin() const _NOEXCEPT {
+ return rbegin();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ // capacity:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return 0; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return 0; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return true; }
+
+ // element access:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference operator[](size_type) const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type) {
+ __throw_out_of_range("array<T, 0>::at");
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type) const {
+ __throw_out_of_range("array<T, 0>::at");
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
+ __libcpp_unreachable();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
+ __libcpp_unreachable();
+ }
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, class... _Args, class = enable_if_t<__all<_IsSame<_Tp, _Args>::value...>::value> >
+array(_Tp, _Args...) -> array<_Tp, 1 + sizeof...(_Args)>;
+#endif
+
+template <class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
+ return std::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
+ return __y < __x;
+}
+
+template <class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
+ return !(__y < __x);
+}
+
+template <class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
+ return !(__x < __y);
+}
+
+#else // _LIBCPP_STD_VER <= 17
+
+template <class _Tp, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI constexpr __synth_three_way_result<_Tp>
+operator<=>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
+ return std::lexicographical_compare_three_way(
+ __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+template <class _Tp, size_t _Size, __enable_if_t<_Size == 0 || __is_swappable_v<_Tp>, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
+ _NOEXCEPT_(noexcept(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+template <class _Tp, size_t _Size>
+struct _LIBCPP_TEMPLATE_VIS tuple_size<array<_Tp, _Size> > : public integral_constant<size_t, _Size> {};
+
+template <size_t _Ip, class _Tp, size_t _Size>
+struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, array<_Tp, _Size> > {
+ static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::array)");
+ typedef _Tp type;
+};
+
+template <size_t _Ip, class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp& get(array<_Tp, _Size>& __a) _NOEXCEPT {
+ static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
+ return __a.__elems_[_Ip];
+}
+
+template <size_t _Ip, class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp& get(const array<_Tp, _Size>& __a) _NOEXCEPT {
+ static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
+ return __a.__elems_[_Ip];
+}
+
+template <size_t _Ip, class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp&& get(array<_Tp, _Size>&& __a) _NOEXCEPT {
+ static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
+ return std::move(__a.__elems_[_Ip]);
+}
+
+template <size_t _Ip, class _Tp, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&& get(const array<_Tp, _Size>&& __a) _NOEXCEPT {
+ static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
+ return std::move(__a.__elems_[_Ip]);
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <typename _Tp, size_t _Size, size_t... _Index>
+_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
+__to_array_lvalue_impl(_Tp (&__arr)[_Size], index_sequence<_Index...>) {
+ return {{__arr[_Index]...}};
+}
+
+template <typename _Tp, size_t _Size, size_t... _Index>
+_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
+__to_array_rvalue_impl(_Tp (&&__arr)[_Size], index_sequence<_Index...>) {
+ return {{std::move(__arr[_Index])...}};
+}
+
+template <typename _Tp, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
+to_array(_Tp (&__arr)[_Size]) noexcept(is_nothrow_constructible_v<_Tp, _Tp&>) {
+ static_assert(!is_array_v<_Tp>, "[array.creation]/1: to_array does not accept multidimensional arrays.");
+ static_assert(is_constructible_v<_Tp, _Tp&>, "[array.creation]/1: to_array requires copy constructible elements.");
+ return std::__to_array_lvalue_impl(__arr, make_index_sequence<_Size>());
+}
+
+template <typename _Tp, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
+to_array(_Tp (&&__arr)[_Size]) noexcept(is_nothrow_move_constructible_v<_Tp>) {
+ static_assert(!is_array_v<_Tp>, "[array.creation]/4: to_array does not accept multidimensional arrays.");
+ static_assert(is_move_constructible_v<_Tp>, "[array.creation]/4: to_array requires move constructible elements.");
+ return std::__to_array_rvalue_impl(std::move(__arr), make_index_sequence<_Size>());
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <concepts>
+# include <cstdlib>
+# include <iterator>
+# include <type_traits>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_ARRAY
diff --git a/libcxx/include/__cxx03/atomic b/libcxx/include/__cxx03/atomic
new file mode 100644
index 00000000000000..0d13619d6ce458
--- /dev/null
+++ b/libcxx/include/__cxx03/atomic
@@ -0,0 +1,632 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_ATOMIC
+#define _LIBCPP_ATOMIC
+
+/*
+ atomic synopsis
+
+namespace std
+{
+
+// feature test macro [version.syn]
+
+#define __cpp_lib_atomic_is_always_lock_free
+#define __cpp_lib_atomic_flag_test
+#define __cpp_lib_atomic_lock_free_type_aliases
+#define __cpp_lib_atomic_wait
+
+ // order and consistency
+
+ enum memory_order: unspecified // enum class in C++20
+ {
+ relaxed,
+ consume, // load-consume
+ acquire, // load-acquire
+ release, // store-release
+ acq_rel, // store-release load-acquire
+ seq_cst // store-release load-acquire
+ };
+
+ inline constexpr auto memory_order_relaxed = memory_order::relaxed;
+ inline constexpr auto memory_order_consume = memory_order::consume;
+ inline constexpr auto memory_order_acquire = memory_order::acquire;
+ inline constexpr auto memory_order_release = memory_order::release;
+ inline constexpr auto memory_order_acq_rel = memory_order::acq_rel;
+ inline constexpr auto memory_order_seq_cst = memory_order::seq_cst;
+
+template <class T> T kill_dependency(T y) noexcept;
+
+// lock-free property
+
+#define ATOMIC_BOOL_LOCK_FREE unspecified
+#define ATOMIC_CHAR_LOCK_FREE unspecified
+#define ATOMIC_CHAR8_T_LOCK_FREE unspecified // C++20
+#define ATOMIC_CHAR16_T_LOCK_FREE unspecified
+#define ATOMIC_CHAR32_T_LOCK_FREE unspecified
+#define ATOMIC_WCHAR_T_LOCK_FREE unspecified
+#define ATOMIC_SHORT_LOCK_FREE unspecified
+#define ATOMIC_INT_LOCK_FREE unspecified
+#define ATOMIC_LONG_LOCK_FREE unspecified
+#define ATOMIC_LLONG_LOCK_FREE unspecified
+#define ATOMIC_POINTER_LOCK_FREE unspecified
+
+template <class T>
+struct atomic
+{
+ using value_type = T;
+
+ static constexpr bool is_always_lock_free;
+ bool is_lock_free() const volatile noexcept;
+ bool is_lock_free() const noexcept;
+
+ atomic() noexcept = default; // until C++20
+ constexpr atomic() noexcept(is_nothrow_default_constructible_v<T>); // since C++20
+ constexpr atomic(T desr) noexcept;
+ atomic(const atomic&) = delete;
+ atomic& operator=(const atomic&) = delete;
+ atomic& operator=(const atomic&) volatile = delete;
+
+ T load(memory_order m = memory_order_seq_cst) const volatile noexcept;
+ T load(memory_order m = memory_order_seq_cst) const noexcept;
+ operator T() const volatile noexcept;
+ operator T() const noexcept;
+ void store(T desr, memory_order m = memory_order_seq_cst) volatile noexcept;
+ void store(T desr, memory_order m = memory_order_seq_cst) noexcept;
+ T operator=(T) volatile noexcept;
+ T operator=(T) noexcept;
+
+ T exchange(T desr, memory_order m = memory_order_seq_cst) volatile noexcept;
+ T exchange(T desr, memory_order m = memory_order_seq_cst) noexcept;
+ bool compare_exchange_weak(T& expc, T desr,
+ memory_order s, memory_order f) volatile noexcept;
+ bool compare_exchange_weak(T& expc, T desr, memory_order s, memory_order f) noexcept;
+ bool compare_exchange_strong(T& expc, T desr,
+ memory_order s, memory_order f) volatile noexcept;
+ bool compare_exchange_strong(T& expc, T desr,
+ memory_order s, memory_order f) noexcept;
+ bool compare_exchange_weak(T& expc, T desr,
+ memory_order m = memory_order_seq_cst) volatile noexcept;
+ bool compare_exchange_weak(T& expc, T desr,
+ memory_order m = memory_order_seq_cst) noexcept;
+ bool compare_exchange_strong(T& expc, T desr,
+ memory_order m = memory_order_seq_cst) volatile noexcept;
+ bool compare_exchange_strong(T& expc, T desr,
+ memory_order m = memory_order_seq_cst) noexcept;
+
+ void wait(T, memory_order = memory_order::seq_cst) const volatile noexcept;
+ void wait(T, memory_order = memory_order::seq_cst) const noexcept;
+ void notify_one() volatile noexcept;
+ void notify_one() noexcept;
+ void notify_all() volatile noexcept;
+ void notify_all() noexcept;
+};
+
+template <>
+struct atomic<integral>
+{
+ using value_type = integral;
+ using difference_type = value_type;
+
+ static constexpr bool is_always_lock_free;
+ bool is_lock_free() const volatile noexcept;
+ bool is_lock_free() const noexcept;
+
+ atomic() noexcept = default;
+ constexpr atomic(integral desr) noexcept;
+ atomic(const atomic&) = delete;
+ atomic& operator=(const atomic&) = delete;
+ atomic& operator=(const atomic&) volatile = delete;
+
+ integral load(memory_order m = memory_order_seq_cst) const volatile noexcept;
+ integral load(memory_order m = memory_order_seq_cst) const noexcept;
+ operator integral() const volatile noexcept;
+ operator integral() const noexcept;
+ void store(integral desr, memory_order m = memory_order_seq_cst) volatile noexcept;
+ void store(integral desr, memory_order m = memory_order_seq_cst) noexcept;
+ integral operator=(integral desr) volatile noexcept;
+ integral operator=(integral desr) noexcept;
+
+ integral exchange(integral desr,
+ memory_order m = memory_order_seq_cst) volatile noexcept;
+ integral exchange(integral desr, memory_order m = memory_order_seq_cst) noexcept;
+ bool compare_exchange_weak(integral& expc, integral desr,
+ memory_order s, memory_order f) volatile noexcept;
+ bool compare_exchange_weak(integral& expc, integral desr,
+ memory_order s, memory_order f) noexcept;
+ bool compare_exchange_strong(integral& expc, integral desr,
+ memory_order s, memory_order f) volatile noexcept;
+ bool compare_exchange_strong(integral& expc, integral desr,
+ memory_order s, memory_order f) noexcept;
+ bool compare_exchange_weak(integral& expc, integral desr,
+ memory_order m = memory_order_seq_cst) volatile noexcept;
+ bool compare_exchange_weak(integral& expc, integral desr,
+ memory_order m = memory_order_seq_cst) noexcept;
+ bool compare_exchange_strong(integral& expc, integral desr,
+ memory_order m = memory_order_seq_cst) volatile noexcept;
+ bool compare_exchange_strong(integral& expc, integral desr,
+ memory_order m = memory_order_seq_cst) noexcept;
+
+ integral fetch_add(integral op, memory_order m = memory_order_seq_cst) volatile noexcept;
+ integral fetch_add(integral op, memory_order m = memory_order_seq_cst) noexcept;
+ integral fetch_sub(integral op, memory_order m = memory_order_seq_cst) volatile noexcept;
+ integral fetch_sub(integral op, memory_order m = memory_order_seq_cst) noexcept;
+ integral fetch_and(integral op, memory_order m = memory_order_seq_cst) volatile noexcept;
+ integral fetch_and(integral op, memory_order m = memory_order_seq_cst) noexcept;
+ integral fetch_or(integral op, memory_order m = memory_order_seq_cst) volatile noexcept;
+ integral fetch_or(integral op, memory_order m = memory_order_seq_cst) noexcept;
+ integral fetch_xor(integral op, memory_order m = memory_order_seq_cst) volatile noexcept;
+ integral fetch_xor(integral op, memory_order m = memory_order_seq_cst) noexcept;
+
+ integral operator++(int) volatile noexcept;
+ integral operator++(int) noexcept;
+ integral operator--(int) volatile noexcept;
+ integral operator--(int) noexcept;
+ integral operator++() volatile noexcept;
+ integral operator++() noexcept;
+ integral operator--() volatile noexcept;
+ integral operator--() noexcept;
+ integral operator+=(integral op) volatile noexcept;
+ integral operator+=(integral op) noexcept;
+ integral operator-=(integral op) volatile noexcept;
+ integral operator-=(integral op) noexcept;
+ integral operator&=(integral op) volatile noexcept;
+ integral operator&=(integral op) noexcept;
+ integral operator|=(integral op) volatile noexcept;
+ integral operator|=(integral op) noexcept;
+ integral operator^=(integral op) volatile noexcept;
+ integral operator^=(integral op) noexcept;
+
+ void wait(integral, memory_order = memory_order::seq_cst) const volatile noexcept;
+ void wait(integral, memory_order = memory_order::seq_cst) const noexcept;
+ void notify_one() volatile noexcept;
+ void notify_one() noexcept;
+ void notify_all() volatile noexcept;
+ void notify_all() noexcept;
+};
+
+template <class T>
+struct atomic<T*>
+{
+ using value_type = T*;
+ using difference_type = ptrdiff_t;
+
+ static constexpr bool is_always_lock_free;
+ bool is_lock_free() const volatile noexcept;
+ bool is_lock_free() const noexcept;
+
+ atomic() noexcept = default; // until C++20
+ constexpr atomic() noexcept; // since C++20
+ constexpr atomic(T* desr) noexcept;
+ atomic(const atomic&) = delete;
+ atomic& operator=(const atomic&) = delete;
+ atomic& operator=(const atomic&) volatile = delete;
+
+ T* load(memory_order m = memory_order_seq_cst) const volatile noexcept;
+ T* load(memory_order m = memory_order_seq_cst) const noexcept;
+ operator T*() const volatile noexcept;
+ operator T*() const noexcept;
+ void store(T* desr, memory_order m = memory_order_seq_cst) volatile noexcept;
+ void store(T* desr, memory_order m = memory_order_seq_cst) noexcept;
+ T* operator=(T*) volatile noexcept;
+ T* operator=(T*) noexcept;
+
+ T* exchange(T* desr, memory_order m = memory_order_seq_cst) volatile noexcept;
+ T* exchange(T* desr, memory_order m = memory_order_seq_cst) noexcept;
+ bool compare_exchange_weak(T*& expc, T* desr,
+ memory_order s, memory_order f) volatile noexcept;
+ bool compare_exchange_weak(T*& expc, T* desr,
+ memory_order s, memory_order f) noexcept;
+ bool compare_exchange_strong(T*& expc, T* desr,
+ memory_order s, memory_order f) volatile noexcept;
+ bool compare_exchange_strong(T*& expc, T* desr,
+ memory_order s, memory_order f) noexcept;
+ bool compare_exchange_weak(T*& expc, T* desr,
+ memory_order m = memory_order_seq_cst) volatile noexcept;
+ bool compare_exchange_weak(T*& expc, T* desr,
+ memory_order m = memory_order_seq_cst) noexcept;
+ bool compare_exchange_strong(T*& expc, T* desr,
+ memory_order m = memory_order_seq_cst) volatile noexcept;
+ bool compare_exchange_strong(T*& expc, T* desr,
+ memory_order m = memory_order_seq_cst) noexcept;
+ T* fetch_add(ptrdiff_t op, memory_order m = memory_order_seq_cst) volatile noexcept;
+ T* fetch_add(ptrdiff_t op, memory_order m = memory_order_seq_cst) noexcept;
+ T* fetch_sub(ptrdiff_t op, memory_order m = memory_order_seq_cst) volatile noexcept;
+ T* fetch_sub(ptrdiff_t op, memory_order m = memory_order_seq_cst) noexcept;
+
+ T* operator++(int) volatile noexcept;
+ T* operator++(int) noexcept;
+ T* operator--(int) volatile noexcept;
+ T* operator--(int) noexcept;
+ T* operator++() volatile noexcept;
+ T* operator++() noexcept;
+ T* operator--() volatile noexcept;
+ T* operator--() noexcept;
+ T* operator+=(ptrdiff_t op) volatile noexcept;
+ T* operator+=(ptrdiff_t op) noexcept;
+ T* operator-=(ptrdiff_t op) volatile noexcept;
+ T* operator-=(ptrdiff_t op) noexcept;
+
+ void wait(T*, memory_order = memory_order::seq_cst) const volatile noexcept;
+ void wait(T*, memory_order = memory_order::seq_cst) const noexcept;
+ void notify_one() volatile noexcept;
+ void notify_one() noexcept;
+ void notify_all() volatile noexcept;
+ void notify_all() noexcept;
+};
+
+template<>
+struct atomic<floating-point-type> { // since C++20
+ using value_type = floating-point-type;
+ using difference_type = value_type;
+
+ static constexpr bool is_always_lock_free = implementation-defined;
+ bool is_lock_free() const volatile noexcept;
+ bool is_lock_free() const noexcept;
+
+ constexpr atomic() noexcept;
+ constexpr atomic(floating-point-type) noexcept;
+ atomic(const atomic&) = delete;
+ atomic& operator=(const atomic&) = delete;
+ atomic& operator=(const atomic&) volatile = delete;
+
+ void store(floating-point-type, memory_order = memory_order::seq_cst) volatile noexcept;
+ void store(floating-point-type, memory_order = memory_order::seq_cst) noexcept;
+ floating-point-type operator=(floating-point-type) volatile noexcept;
+ floating-point-type operator=(floating-point-type) noexcept;
+ floating-point-type load(memory_order = memory_order::seq_cst) volatile noexcept;
+ floating-point-type load(memory_order = memory_order::seq_cst) noexcept;
+ operator floating-point-type() volatile noexcept;
+ operator floating-point-type() noexcept;
+
+ floating-point-type exchange(floating-point-type,
+ memory_order = memory_order::seq_cst) volatile noexcept;
+ floating-point-type exchange(floating-point-type,
+ memory_order = memory_order::seq_cst) noexcept;
+ bool compare_exchange_weak(floating-point-type&, floating-point-type,
+ memory_order, memory_order) volatile noexcept;
+ bool compare_exchange_weak(floating-point-type&, floating-point-type,
+ memory_order, memory_order) noexcept;
+ bool compare_exchange_strong(floating-point-type&, floating-point-type,
+ memory_order, memory_order) volatile noexcept;
+ bool compare_exchange_strong(floating-point-type&, floating-point-type,
+ memory_order, memory_order) noexcept;
+ bool compare_exchange_weak(floating-point-type&, floating-point-type,
+ memory_order = memory_order::seq_cst) volatile noexcept;
+ bool compare_exchange_weak(floating-point-type&, floating-point-type,
+ memory_order = memory_order::seq_cst) noexcept;
+ bool compare_exchange_strong(floating-point-type&, floating-point-type,
+ memory_order = memory_order::seq_cst) volatile noexcept;
+ bool compare_exchange_strong(floating-point-type&, floating-point-type,
+ memory_order = memory_order::seq_cst) noexcept;
+
+ floating-point-type fetch_add(floating-point-type,
+ memory_order = memory_order::seq_cst) volatile noexcept;
+ floating-point-type fetch_add(floating-point-type,
+ memory_order = memory_order::seq_cst) noexcept;
+ floating-point-type fetch_sub(floating-point-type,
+ memory_order = memory_order::seq_cst) volatile noexcept;
+ floating-point-type fetch_sub(floating-point-type,
+ memory_order = memory_order::seq_cst) noexcept;
+
+ floating-point-type operator+=(floating-point-type) volatile noexcept;
+ floating-point-type operator+=(floating-point-type) noexcept;
+ floating-point-type operator-=(floating-point-type) volatile noexcept;
+ floating-point-type operator-=(floating-point-type) noexcept;
+
+ void wait(floating-point-type, memory_order = memory_order::seq_cst) const volatile noexcept;
+ void wait(floating-point-type, memory_order = memory_order::seq_cst) const noexcept;
+ void notify_one() volatile noexcept;
+ void notify_one() noexcept;
+ void notify_all() volatile noexcept;
+ void notify_all() noexcept;
+};
+
+// [atomics.nonmembers], non-member functions
+template<class T>
+ bool atomic_is_lock_free(const volatile atomic<T>*) noexcept;
+template<class T>
+ bool atomic_is_lock_free(const atomic<T>*) noexcept;
+template<class T>
+ void atomic_store(volatile atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ void atomic_store(atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ void atomic_store_explicit(volatile atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ void atomic_store_explicit(atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_load(const volatile atomic<T>*) noexcept;
+template<class T>
+ T atomic_load(const atomic<T>*) noexcept;
+template<class T>
+ T atomic_load_explicit(const volatile atomic<T>*, memory_order) noexcept;
+template<class T>
+ T atomic_load_explicit(const atomic<T>*, memory_order) noexcept;
+template<class T>
+ T atomic_exchange(volatile atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ T atomic_exchange(atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ T atomic_exchange_explicit(volatile atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_exchange_explicit(atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ bool atomic_compare_exchange_weak(volatile atomic<T>*, atomic<T>::value_type*,
+ atomic<T>::value_type) noexcept;
+template<class T>
+ bool atomic_compare_exchange_weak(atomic<T>*, atomic<T>::value_type*,
+ atomic<T>::value_type) noexcept;
+template<class T>
+ bool atomic_compare_exchange_strong(volatile atomic<T>*, atomic<T>::value_type*,
+ atomic<T>::value_type) noexcept;
+template<class T>
+ bool atomic_compare_exchange_strong(atomic<T>*, atomic<T>::value_type*,
+ atomic<T>::value_type) noexcept;
+template<class T>
+ bool atomic_compare_exchange_weak_explicit(volatile atomic<T>*, atomic<T>::value_type*,
+ atomic<T>::value_type,
+ memory_order, memory_order) noexcept;
+template<class T>
+ bool atomic_compare_exchange_weak_explicit(atomic<T>*, atomic<T>::value_type*,
+ atomic<T>::value_type,
+ memory_order, memory_order) noexcept;
+template<class T>
+ bool atomic_compare_exchange_strong_explicit(volatile atomic<T>*, atomic<T>::value_type*,
+ atomic<T>::value_type,
+ memory_order, memory_order) noexcept;
+template<class T>
+ bool atomic_compare_exchange_strong_explicit(atomic<T>*, atomic<T>::value_type*,
+ atomic<T>::value_type,
+ memory_order, memory_order) noexcept;
+
+template<class T>
+ T atomic_fetch_add(volatile atomic<T>*, atomic<T>::difference_type) noexcept;
+template<class T>
+ T atomic_fetch_add(atomic<T>*, atomic<T>::difference_type) noexcept;
+template<class T>
+ T atomic_fetch_add_explicit(volatile atomic<T>*, atomic<T>::difference_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_add_explicit(atomic<T>*, atomic<T>::difference_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_sub(volatile atomic<T>*, atomic<T>::difference_type) noexcept;
+template<class T>
+ T atomic_fetch_sub(atomic<T>*, atomic<T>::difference_type) noexcept;
+template<class T>
+ T atomic_fetch_sub_explicit(volatile atomic<T>*, atomic<T>::difference_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_sub_explicit(atomic<T>*, atomic<T>::difference_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_and(volatile atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ T atomic_fetch_and(atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ T atomic_fetch_and_explicit(volatile atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_and_explicit(atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_or(volatile atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ T atomic_fetch_or(atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ T atomic_fetch_or_explicit(volatile atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_or_explicit(atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_xor(volatile atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ T atomic_fetch_xor(atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ T atomic_fetch_xor_explicit(volatile atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ T atomic_fetch_xor_explicit(atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+
+template<class T>
+ void atomic_wait(const volatile atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ void atomic_wait(const atomic<T>*, atomic<T>::value_type) noexcept;
+template<class T>
+ void atomic_wait_explicit(const volatile atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ void atomic_wait_explicit(const atomic<T>*, atomic<T>::value_type,
+ memory_order) noexcept;
+template<class T>
+ void atomic_notify_one(volatile atomic<T>*) noexcept;
+template<class T>
+ void atomic_notify_one(atomic<T>*) noexcept;
+template<class T>
+ void atomic_notify_all(volatile atomic<T>*) noexcept;
+template<class T>
+ void atomic_notify_all(atomic<T>*) noexcept;
+
+// Atomics for standard typedef types
+
+typedef atomic<bool> atomic_bool;
+typedef atomic<char> atomic_char;
+typedef atomic<signed char> atomic_schar;
+typedef atomic<unsigned char> atomic_uchar;
+typedef atomic<short> atomic_short;
+typedef atomic<unsigned short> atomic_ushort;
+typedef atomic<int> atomic_int;
+typedef atomic<unsigned int> atomic_uint;
+typedef atomic<long> atomic_long;
+typedef atomic<unsigned long> atomic_ulong;
+typedef atomic<long long> atomic_llong;
+typedef atomic<unsigned long long> atomic_ullong;
+typedef atomic<char8_t> atomic_char8_t; // C++20
+typedef atomic<char16_t> atomic_char16_t;
+typedef atomic<char32_t> atomic_char32_t;
+typedef atomic<wchar_t> atomic_wchar_t;
+
+typedef atomic<int_least8_t> atomic_int_least8_t;
+typedef atomic<uint_least8_t> atomic_uint_least8_t;
+typedef atomic<int_least16_t> atomic_int_least16_t;
+typedef atomic<uint_least16_t> atomic_uint_least16_t;
+typedef atomic<int_least32_t> atomic_int_least32_t;
+typedef atomic<uint_least32_t> atomic_uint_least32_t;
+typedef atomic<int_least64_t> atomic_int_least64_t;
+typedef atomic<uint_least64_t> atomic_uint_least64_t;
+
+typedef atomic<int_fast8_t> atomic_int_fast8_t;
+typedef atomic<uint_fast8_t> atomic_uint_fast8_t;
+typedef atomic<int_fast16_t> atomic_int_fast16_t;
+typedef atomic<uint_fast16_t> atomic_uint_fast16_t;
+typedef atomic<int_fast32_t> atomic_int_fast32_t;
+typedef atomic<uint_fast32_t> atomic_uint_fast32_t;
+typedef atomic<int_fast64_t> atomic_int_fast64_t;
+typedef atomic<uint_fast64_t> atomic_uint_fast64_t;
+
+typedef atomic<int8_t> atomic_int8_t;
+typedef atomic<uint8_t> atomic_uint8_t;
+typedef atomic<int16_t> atomic_int16_t;
+typedef atomic<uint16_t> atomic_uint16_t;
+typedef atomic<int32_t> atomic_int32_t;
+typedef atomic<uint32_t> atomic_uint32_t;
+typedef atomic<int64_t> atomic_int64_t;
+typedef atomic<uint64_t> atomic_uint64_t;
+
+typedef atomic<intptr_t> atomic_intptr_t;
+typedef atomic<uintptr_t> atomic_uintptr_t;
+typedef atomic<size_t> atomic_size_t;
+typedef atomic<ptrdiff_t> atomic_ptrdiff_t;
+typedef atomic<intmax_t> atomic_intmax_t;
+typedef atomic<uintmax_t> atomic_uintmax_t;
+
+typedef see-below atomic_signed_lock_free; // since C++20
+typedef see-below atomic_unsigned_lock_free; // since C++20
+
+// flag type and operations
+
+typedef struct atomic_flag
+{
+ atomic_flag() noexcept = default; // until C++20
+ constexpr atomic_flag() noexcept; // since C++20
+ atomic_flag(const atomic_flag&) = delete;
+ atomic_flag& operator=(const atomic_flag&) = delete;
+ atomic_flag& operator=(const atomic_flag&) volatile = delete;
+
+ bool test(memory_order m = memory_order_seq_cst) volatile noexcept;
+ bool test(memory_order m = memory_order_seq_cst) noexcept;
+ bool test_and_set(memory_order m = memory_order_seq_cst) volatile noexcept;
+ bool test_and_set(memory_order m = memory_order_seq_cst) noexcept;
+ void clear(memory_order m = memory_order_seq_cst) volatile noexcept;
+ void clear(memory_order m = memory_order_seq_cst) noexcept;
+
+ void wait(bool, memory_order = memory_order::seq_cst) const volatile noexcept;
+ void wait(bool, memory_order = memory_order::seq_cst) const noexcept;
+ void notify_one() volatile noexcept;
+ void notify_one() noexcept;
+ void notify_all() volatile noexcept;
+ void notify_all() noexcept;
+} atomic_flag;
+
+bool atomic_flag_test(volatile atomic_flag* obj) noexcept;
+bool atomic_flag_test(atomic_flag* obj) noexcept;
+bool atomic_flag_test_explicit(volatile atomic_flag* obj,
+ memory_order m) noexcept;
+bool atomic_flag_test_explicit(atomic_flag* obj, memory_order m) noexcept;
+bool atomic_flag_test_and_set(volatile atomic_flag* obj) noexcept;
+bool atomic_flag_test_and_set(atomic_flag* obj) noexcept;
+bool atomic_flag_test_and_set_explicit(volatile atomic_flag* obj,
+ memory_order m) noexcept;
+bool atomic_flag_test_and_set_explicit(atomic_flag* obj, memory_order m) noexcept;
+void atomic_flag_clear(volatile atomic_flag* obj) noexcept;
+void atomic_flag_clear(atomic_flag* obj) noexcept;
+void atomic_flag_clear_explicit(volatile atomic_flag* obj, memory_order m) noexcept;
+void atomic_flag_clear_explicit(atomic_flag* obj, memory_order m) noexcept;
+
+void atomic_wait(const volatile atomic_flag* obj, T old) noexcept;
+void atomic_wait(const atomic_flag* obj, T old) noexcept;
+void atomic_wait_explicit(const volatile atomic_flag* obj, T old, memory_order m) noexcept;
+void atomic_wait_explicit(const atomic_flag* obj, T old, memory_order m) noexcept;
+void atomic_one(volatile atomic_flag* obj) noexcept;
+void atomic_one(atomic_flag* obj) noexcept;
+void atomic_all(volatile atomic_flag* obj) noexcept;
+void atomic_all(atomic_flag* obj) noexcept;
+
+// fences
+
+void atomic_thread_fence(memory_order m) noexcept;
+void atomic_signal_fence(memory_order m) noexcept;
+
+// deprecated
+
+template <class T>
+ void atomic_init(volatile atomic<T>* obj, atomic<T>::value_type desr) noexcept;
+
+template <class T>
+ void atomic_init(atomic<T>* obj, atomic<T>::value_type desr) noexcept;
+
+#define ATOMIC_VAR_INIT(value) see below
+
+#define ATOMIC_FLAG_INIT see below
+
+} // std
+
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER < 23 && defined(_LIBCPP_STDATOMIC_H)
+# error <atomic> is incompatible with <stdatomic.h> before C++23. Please compile with -std=c++23.
+#endif
+
+#include <__atomic/aliases.h>
+#include <__atomic/atomic.h>
+#include <__atomic/atomic_base.h>
+#include <__atomic/atomic_flag.h>
+#include <__atomic/atomic_init.h>
+#include <__atomic/atomic_lock_free.h>
+#include <__atomic/atomic_sync.h>
+#include <__atomic/check_memory_order.h>
+#include <__atomic/contention_t.h>
+#include <__atomic/cxx_atomic_impl.h>
+#include <__atomic/fence.h>
+#include <__atomic/is_always_lock_free.h>
+#include <__atomic/kill_dependency.h>
+#include <__atomic/memory_order.h>
+#include <version>
+
+#if _LIBCPP_STD_VER >= 20
+# include <__atomic/atomic_ref.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifdef _LIBCPP_HAS_NO_ATOMIC_HEADER
+# error <atomic> is not implemented
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cmath>
+# include <compare>
+# include <cstdlib>
+# include <cstring>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_ATOMIC
diff --git a/libcxx/include/__cxx03/barrier b/libcxx/include/__cxx03/barrier
new file mode 100644
index 00000000000000..edee181273e248
--- /dev/null
+++ b/libcxx/include/__cxx03/barrier
@@ -0,0 +1,308 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_BARRIER
+#define _LIBCPP_BARRIER
+
+/*
+ barrier synopsis
+
+namespace std
+{
+
+ template<class CompletionFunction = see below>
+ class barrier
+ {
+ public:
+ using arrival_token = see below;
+
+ static constexpr ptrdiff_t max() noexcept;
+
+ constexpr explicit barrier(ptrdiff_t phase_count,
+ CompletionFunction f = CompletionFunction());
+ ~barrier();
+
+ barrier(const barrier&) = delete;
+ barrier& operator=(const barrier&) = delete;
+
+ [[nodiscard]] arrival_token arrive(ptrdiff_t update = 1);
+ void wait(arrival_token&& arrival) const;
+
+ void arrive_and_wait();
+ void arrive_and_drop();
+
+ private:
+ CompletionFunction completion; // exposition only
+ };
+
+}
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+# include <__assert>
+# include <__atomic/atomic_base.h>
+# include <__atomic/memory_order.h>
+# include <__memory/unique_ptr.h>
+# include <__thread/poll_with_backoff.h>
+# include <__thread/timed_backoff_policy.h>
+# include <__utility/move.h>
+# include <cstddef>
+# include <cstdint>
+# include <limits>
+# include <version>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+# if _LIBCPP_STD_VER >= 14
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __empty_completion {
+ inline _LIBCPP_HIDE_FROM_ABI void operator()() noexcept {}
+};
+
+# ifndef _LIBCPP_HAS_NO_TREE_BARRIER
+
+/*
+
+The default implementation of __barrier_base is a classic tree barrier.
+
+It looks different from literature pseudocode for two main reasons:
+ 1. Threads that call into std::barrier functions do not provide indices,
+ so a numbering step is added before the actual barrier algorithm,
+ appearing as an N+1 round to the N rounds of the tree barrier.
+ 2. A great deal of attention has been paid to avoid cache line thrashing
+ by flattening the tree structure into cache-line sized arrays, that
+ are indexed in an efficient way.
+
+*/
+
+using __barrier_phase_t = uint8_t;
+
+class __barrier_algorithm_base;
+
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI __barrier_algorithm_base*
+__construct_barrier_algorithm_base(ptrdiff_t& __expected);
+
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI bool
+__arrive_barrier_algorithm_base(__barrier_algorithm_base* __barrier, __barrier_phase_t __old_phase) noexcept;
+
+_LIBCPP_AVAILABILITY_SYNC _LIBCPP_EXPORTED_FROM_ABI void
+__destroy_barrier_algorithm_base(__barrier_algorithm_base* __barrier) noexcept;
+
+template <class _CompletionF>
+class __barrier_base {
+ ptrdiff_t __expected_;
+ unique_ptr<__barrier_algorithm_base, void (*)(__barrier_algorithm_base*)> __base_;
+ __atomic_base<ptrdiff_t> __expected_adjustment_;
+ _CompletionF __completion_;
+ __atomic_base<__barrier_phase_t> __phase_;
+
+public:
+ using arrival_token = __barrier_phase_t;
+
+ static _LIBCPP_HIDE_FROM_ABI constexpr ptrdiff_t max() noexcept { return numeric_limits<ptrdiff_t>::max(); }
+
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI
+ __barrier_base(ptrdiff_t __expected, _CompletionF __completion = _CompletionF())
+ : __expected_(__expected),
+ __base_(std::__construct_barrier_algorithm_base(this->__expected_), &__destroy_barrier_algorithm_base),
+ __expected_adjustment_(0),
+ __completion_(std::move(__completion)),
+ __phase_(0) {}
+ _LIBCPP_NODISCARD _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI arrival_token arrive(ptrdiff_t __update) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __update <= __expected_, "update is greater than the expected count for the current barrier phase");
+
+ auto const __old_phase = __phase_.load(memory_order_relaxed);
+ for (; __update; --__update)
+ if (__arrive_barrier_algorithm_base(__base_.get(), __old_phase)) {
+ __completion_();
+ __expected_ += __expected_adjustment_.load(memory_order_relaxed);
+ __expected_adjustment_.store(0, memory_order_relaxed);
+ __phase_.store(__old_phase + 2, memory_order_release);
+ __phase_.notify_all();
+ }
+ return __old_phase;
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void wait(arrival_token&& __old_phase) const {
+ auto const __test_fn = [this, __old_phase]() -> bool { return __phase_.load(memory_order_acquire) != __old_phase; };
+ std::__libcpp_thread_poll_with_backoff(__test_fn, __libcpp_timed_backoff_policy());
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void arrive_and_drop() {
+ __expected_adjustment_.fetch_sub(1, memory_order_relaxed);
+ (void)arrive(1);
+ }
+};
+
+# else
+
+/*
+
+The alternative implementation of __barrier_base is a central barrier.
+
+Two versions of this algorithm are provided:
+ 1. A fairly straightforward implementation of the litterature for the
+ general case where the completion function is not empty.
+ 2. An optimized implementation that exploits 2's complement arithmetic
+ and well-defined overflow in atomic arithmetic, to handle the phase
+ roll-over for free.
+
+*/
+
+template <class _CompletionF>
+class __barrier_base {
+ __atomic_base<ptrdiff_t> __expected;
+ __atomic_base<ptrdiff_t> __arrived;
+ _CompletionF __completion;
+ __atomic_base<bool> __phase;
+
+public:
+ using arrival_token = bool;
+
+ static constexpr ptrdiff_t max() noexcept { return numeric_limits<ptrdiff_t>::max(); }
+
+ _LIBCPP_HIDE_FROM_ABI __barrier_base(ptrdiff_t __expected, _CompletionF __completion = _CompletionF())
+ : __expected(__expected), __arrived(__expected), __completion(std::move(__completion)), __phase(false) {}
+ [[nodiscard]] _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI arrival_token arrive(ptrdiff_t update) {
+ auto const __old_phase = __phase.load(memory_order_relaxed);
+ auto const __result = __arrived.fetch_sub(update, memory_order_acq_rel) - update;
+ auto const new_expected = __expected.load(memory_order_relaxed);
+
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ update <= new_expected, "update is greater than the expected count for the current barrier phase");
+
+ if (0 == __result) {
+ __completion();
+ __arrived.store(new_expected, memory_order_relaxed);
+ __phase.store(!__old_phase, memory_order_release);
+ __phase.notify_all();
+ }
+ return __old_phase;
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void wait(arrival_token&& __old_phase) const {
+ __phase.wait(__old_phase, memory_order_acquire);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void arrive_and_drop() {
+ __expected.fetch_sub(1, memory_order_relaxed);
+ (void)arrive(1);
+ }
+};
+
+template <>
+class __barrier_base<__empty_completion> {
+ static constexpr uint64_t __expected_unit = 1ull;
+ static constexpr uint64_t __arrived_unit = 1ull << 32;
+ static constexpr uint64_t __expected_mask = __arrived_unit - 1;
+ static constexpr uint64_t __phase_bit = 1ull << 63;
+ static constexpr uint64_t __arrived_mask = (__phase_bit - 1) & ~__expected_mask;
+
+ __atomic_base<uint64_t> __phase_arrived_expected;
+
+ static _LIBCPP_HIDE_FROM_ABI constexpr uint64_t __init(ptrdiff_t __count) _NOEXCEPT {
+ return ((uint64_t(1u << 31) - __count) << 32) | (uint64_t(1u << 31) - __count);
+ }
+
+public:
+ using arrival_token = uint64_t;
+
+ static constexpr ptrdiff_t max() noexcept { return ptrdiff_t(1u << 31) - 1; }
+
+ _LIBCPP_HIDE_FROM_ABI explicit inline __barrier_base(ptrdiff_t __count, __empty_completion = __empty_completion())
+ : __phase_arrived_expected(__init(__count)) {}
+ [[nodiscard]] inline _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI arrival_token arrive(ptrdiff_t update) {
+ auto const __inc = __arrived_unit * update;
+ auto const __old = __phase_arrived_expected.fetch_add(__inc, memory_order_acq_rel);
+
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ update <= __old, "update is greater than the expected count for the current barrier phase");
+
+ if ((__old ^ (__old + __inc)) & __phase_bit) {
+ __phase_arrived_expected.fetch_add((__old & __expected_mask) << 32, memory_order_relaxed);
+ __phase_arrived_expected.notify_all();
+ }
+ return __old & __phase_bit;
+ }
+ inline _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void wait(arrival_token&& __phase) const {
+ auto const __test_fn = [=]() -> bool {
+ uint64_t const __current = __phase_arrived_expected.load(memory_order_acquire);
+ return ((__current & __phase_bit) != __phase);
+ };
+ __libcpp_thread_poll_with_backoff(__test_fn, __libcpp_timed_backoff_policy());
+ }
+ inline _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void arrive_and_drop() {
+ __phase_arrived_expected.fetch_add(__expected_unit, memory_order_relaxed);
+ (void)arrive(1);
+ }
+};
+
+# endif // !_LIBCPP_HAS_NO_TREE_BARRIER
+
+template <class _CompletionF = __empty_completion>
+class _LIBCPP_DEPRECATED_ATOMIC_SYNC barrier {
+ __barrier_base<_CompletionF> __b_;
+
+public:
+ using arrival_token = typename __barrier_base<_CompletionF>::arrival_token;
+
+ static _LIBCPP_HIDE_FROM_ABI constexpr ptrdiff_t max() noexcept { return __barrier_base<_CompletionF>::max(); }
+
+ _LIBCPP_AVAILABILITY_SYNC
+ _LIBCPP_HIDE_FROM_ABI explicit barrier(ptrdiff_t __count, _CompletionF __completion = _CompletionF())
+ : __b_(__count, std::move(__completion)) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __count >= 0,
+ "barrier::barrier(ptrdiff_t, CompletionFunction): barrier cannot be initialized with a negative value");
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __count <= max(),
+ "barrier::barrier(ptrdiff_t, CompletionFunction): barrier cannot be initialized with "
+ "a value greater than max()");
+ }
+
+ barrier(barrier const&) = delete;
+ barrier& operator=(barrier const&) = delete;
+
+ _LIBCPP_NODISCARD _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI arrival_token arrive(ptrdiff_t __update = 1) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(__update > 0, "barrier:arrive must be called with a value greater than 0");
+ return __b_.arrive(__update);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void wait(arrival_token&& __phase) const {
+ __b_.wait(std::move(__phase));
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void arrive_and_wait() { wait(arrive()); }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void arrive_and_drop() { __b_.arrive_and_drop(); }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+# endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_THREADS)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <iterator>
+# include <memory>
+# include <stdexcept>
+# include <variant>
+#endif
+
+#endif //_LIBCPP_BARRIER
diff --git a/libcxx/include/__cxx03/bit b/libcxx/include/__cxx03/bit
new file mode 100644
index 00000000000000..94387d101a398f
--- /dev/null
+++ b/libcxx/include/__cxx03/bit
@@ -0,0 +1,101 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_BIT
+#define _LIBCPP_BIT
+
+/*
+ bit synopsis
+
+namespace std {
+ // [bit.cast], bit_cast
+ template<class To, class From>
+ constexpr To bit_cast(const From& from) noexcept; // C++20
+
+ // [bit.byteswap], byteswap
+ template<class T>
+ constexpr T byteswap(T value) noexcept; // C++23
+
+ // [bit.pow.two], integral powers of 2
+ template <class T>
+ constexpr bool has_single_bit(T x) noexcept; // C++20
+ template <class T>
+ constexpr T bit_ceil(T x); // C++20
+ template <class T>
+ constexpr T bit_floor(T x) noexcept; // C++20
+ template <class T>
+ constexpr int bit_width(T x) noexcept; // C++20
+
+ // [bit.rotate], rotating
+ template<class T>
+ constexpr T rotl(T x, int s) noexcept; // C++20
+ template<class T>
+ constexpr T rotr(T x, int s) noexcept; // C++20
+
+ // [bit.count], counting
+ template<class T>
+ constexpr int countl_zero(T x) noexcept; // C++20
+ template<class T>
+ constexpr int countl_one(T x) noexcept; // C++20
+ template<class T>
+ constexpr int countr_zero(T x) noexcept; // C++20
+ template<class T>
+ constexpr int countr_one(T x) noexcept; // C++20
+ template<class T>
+ constexpr int popcount(T x) noexcept; // C++20
+
+ // [bit.endian], endian
+ enum class endian {
+ little = see below, // C++20
+ big = see below, // C++20
+ native = see below // C++20
+ };
+
+} // namespace std
+
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 20
+# include <__bit/bit_cast.h>
+# include <__bit/bit_ceil.h>
+# include <__bit/bit_floor.h>
+# include <__bit/bit_log2.h>
+# include <__bit/bit_width.h>
+# include <__bit/countl.h>
+# include <__bit/countr.h>
+# include <__bit/endian.h>
+# include <__bit/has_single_bit.h>
+# include <__bit/popcount.h>
+# include <__bit/rotate.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+# include <__bit/byteswap.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <cstdint>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdlib>
+# include <iosfwd>
+# include <limits>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_BIT
diff --git a/libcxx/include/__cxx03/bitset b/libcxx/include/__cxx03/bitset
new file mode 100644
index 00000000000000..6bd7bfe585f38a
--- /dev/null
+++ b/libcxx/include/__cxx03/bitset
@@ -0,0 +1,969 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_BITSET
+#define _LIBCPP_BITSET
+
+// clang-format off
+
+/*
+ bitset synopsis
+
+namespace std
+{
+
+namespace std {
+
+template <size_t N>
+class bitset
+{
+public:
+ // bit reference:
+ class reference
+ {
+ friend class bitset;
+ reference() noexcept;
+ public:
+ ~reference() noexcept;
+ reference& operator=(bool x) noexcept; // for b[i] = x;
+ reference& operator=(const reference&) noexcept; // for b[i] = b[j];
+ bool operator~() const noexcept; // flips the bit
+ operator bool() const noexcept; // for x = b[i];
+ reference& flip() noexcept; // for b[i].flip();
+ };
+
+ // 23.3.5.1 constructors:
+ constexpr bitset() noexcept;
+ constexpr bitset(unsigned long long val) noexcept;
+ template <class charT>
+ constexpr explicit bitset(const charT* str,
+ typename basic_string<charT>::size_type n = basic_string<charT>::npos,
+ charT zero = charT('0'), charT one = charT('1')); // until C++26, constexpr since C++23
+ template <class charT>
+ constexpr explicit bitset(const charT* str,
+ typename basic_string_view<charT>::size_type n = basic_string_view<charT>::npos,
+ charT zero = charT('0'), charT one = charT('1')); // since C++26
+ template<class charT, class traits>
+ explicit bitset(
+ const basic_string_view<charT,traits>& str,
+ typename basic_string_view<charT,traits>::size_type pos = 0,
+ typename basic_string_view<charT,traits>::size_type n = basic_string_view<charT,traits>::npos,
+ charT zero = charT('0'), charT one = charT('1')); // since C++26
+ template<class charT, class traits, class Allocator>
+ constexpr explicit bitset(
+ const basic_string<charT,traits,Allocator>& str,
+ typename basic_string<charT,traits,Allocator>::size_type pos = 0,
+ typename basic_string<charT,traits,Allocator>::size_type n = basic_string<charT,traits,Allocator>::npos,
+ charT zero = charT('0'), charT one = charT('1')); // constexpr since C++23
+
+ // 23.3.5.2 bitset operations:
+ bitset& operator&=(const bitset& rhs) noexcept; // constexpr since C++23
+ bitset& operator|=(const bitset& rhs) noexcept; // constexpr since C++23
+ bitset& operator^=(const bitset& rhs) noexcept; // constexpr since C++23
+ bitset& operator<<=(size_t pos) noexcept; // constexpr since C++23
+ bitset& operator>>=(size_t pos) noexcept; // constexpr since C++23
+ bitset& set() noexcept; // constexpr since C++23
+ bitset& set(size_t pos, bool val = true); // constexpr since C++23
+ bitset& reset() noexcept; // constexpr since C++23
+ bitset& reset(size_t pos); // constexpr since C++23
+ bitset operator~() const noexcept; // constexpr since C++23
+ bitset& flip() noexcept; // constexpr since C++23
+ bitset& flip(size_t pos); // constexpr since C++23
+
+ // element access:
+ constexpr bool operator[](size_t pos) const;
+ reference operator[](size_t pos); // constexpr since C++23
+ unsigned long to_ulong() const; // constexpr since C++23
+ unsigned long long to_ullong() const; // constexpr since C++23
+ template <class charT, class traits, class Allocator> // constexpr since C++23
+ basic_string<charT, traits, Allocator> to_string(charT zero = charT('0'), charT one = charT('1')) const;
+ template <class charT, class traits> // constexpr since C++23
+ basic_string<charT, traits, allocator<charT> > to_string(charT zero = charT('0'), charT one = charT('1')) const;
+ template <class charT> // constexpr since C++23
+ basic_string<charT, char_traits<charT>, allocator<charT> > to_string(charT zero = charT('0'), charT one = charT('1')) const;
+ basic_string<char, char_traits<char>, allocator<char> > to_string(char zero = '0', char one = '1') const; // constexpr since C++23
+ size_t count() const noexcept; // constexpr since C++23
+ constexpr size_t size() const noexcept; // constexpr since C++23
+ bool operator==(const bitset& rhs) const noexcept; // constexpr since C++23
+ bool operator!=(const bitset& rhs) const noexcept; // removed in C++20
+ bool test(size_t pos) const; // constexpr since C++23
+ bool all() const noexcept; // constexpr since C++23
+ bool any() const noexcept; // constexpr since C++23
+ bool none() const noexcept; // constexpr since C++23
+ bitset<N> operator<<(size_t pos) const noexcept; // constexpr since C++23
+ bitset<N> operator>>(size_t pos) const noexcept; // constexpr since C++23
+};
+
+// 23.3.5.3 bitset operators:
+template <size_t N>
+bitset<N> operator&(const bitset<N>&, const bitset<N>&) noexcept; // constexpr since C++23
+
+template <size_t N>
+bitset<N> operator|(const bitset<N>&, const bitset<N>&) noexcept; // constexpr since C++23
+
+template <size_t N>
+bitset<N> operator^(const bitset<N>&, const bitset<N>&) noexcept; // constexpr since C++23
+
+template <class charT, class traits, size_t N>
+basic_istream<charT, traits>&
+operator>>(basic_istream<charT, traits>& is, bitset<N>& x);
+
+template <class charT, class traits, size_t N>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& os, const bitset<N>& x);
+
+template <size_t N> struct hash<std::bitset<N>>;
+
+} // std
+
+*/
+
+// clang-format on
+
+#include <__algorithm/count.h>
+#include <__algorithm/fill.h>
+#include <__algorithm/find.h>
+#include <__bit_reference>
+#include <__config>
+#include <__functional/hash.h>
+#include <__functional/unary_function.h>
+#include <__type_traits/is_char_like_type.h>
+#include <climits>
+#include <cstddef>
+#include <stdexcept>
+#include <string_view>
+#include <version>
+
+// standard-mandated includes
+
+// [bitset.syn]
+#include <iosfwd>
+#include <string>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <size_t _N_words, size_t _Size>
+class __bitset;
+
+template <size_t _N_words, size_t _Size>
+struct __has_storage_type<__bitset<_N_words, _Size> > {
+ static const bool value = true;
+};
+
+template <size_t _N_words, size_t _Size>
+class __bitset {
+public:
+ typedef ptrdiff_t difference_type;
+ typedef size_t size_type;
+ typedef size_type __storage_type;
+
+protected:
+ typedef __bitset __self;
+ typedef __storage_type* __storage_pointer;
+ typedef const __storage_type* __const_storage_pointer;
+ static const unsigned __bits_per_word = static_cast<unsigned>(sizeof(__storage_type) * CHAR_BIT);
+
+ friend class __bit_reference<__bitset>;
+ friend class __bit_const_reference<__bitset>;
+ friend class __bit_iterator<__bitset, false>;
+ friend class __bit_iterator<__bitset, true>;
+ friend struct __bit_array<__bitset>;
+
+ __storage_type __first_[_N_words];
+
+ typedef __bit_reference<__bitset> reference;
+ typedef __bit_const_reference<__bitset> const_reference;
+ typedef __bit_iterator<__bitset, false> iterator;
+ typedef __bit_iterator<__bitset, true> const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __bitset() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI explicit _LIBCPP_CONSTEXPR __bitset(unsigned long long __v) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 reference __make_ref(size_t __pos) _NOEXCEPT {
+ return reference(__first_ + __pos / __bits_per_word, __storage_type(1) << __pos % __bits_per_word);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference __make_ref(size_t __pos) const _NOEXCEPT {
+ return const_reference(__first_ + __pos / __bits_per_word, __storage_type(1) << __pos % __bits_per_word);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 iterator __make_iter(size_t __pos) _NOEXCEPT {
+ return iterator(__first_ + __pos / __bits_per_word, __pos % __bits_per_word);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 const_iterator __make_iter(size_t __pos) const _NOEXCEPT {
+ return const_iterator(__first_ + __pos / __bits_per_word, __pos % __bits_per_word);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator&=(const __bitset& __v) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator|=(const __bitset& __v) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator^=(const __bitset& __v) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void flip() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long to_ulong() const {
+ return to_ulong(integral_constant < bool, _Size< sizeof(unsigned long) * CHAR_BIT>());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong() const {
+ return to_ullong(integral_constant < bool, _Size< sizeof(unsigned long long) * CHAR_BIT>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool all() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool any() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI size_t __hash_code() const _NOEXCEPT;
+
+private:
+#ifdef _LIBCPP_CXX03_LANG
+ void __init(unsigned long long __v, false_type) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI void __init(unsigned long long __v, true_type) _NOEXCEPT;
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long to_ulong(false_type) const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long to_ulong(true_type) const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong(false_type) const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong(true_type) const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong(true_type, false_type) const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong(true_type, true_type) const;
+};
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_CONSTEXPR __bitset<_N_words, _Size>::__bitset() _NOEXCEPT
+#ifndef _LIBCPP_CXX03_LANG
+ : __first_{0}
+#endif
+{
+#ifdef _LIBCPP_CXX03_LANG
+ std::fill_n(__first_, _N_words, __storage_type(0));
+#endif
+}
+
+#ifdef _LIBCPP_CXX03_LANG
+
+template <size_t _N_words, size_t _Size>
+void __bitset<_N_words, _Size>::__init(unsigned long long __v, false_type) _NOEXCEPT {
+ __storage_type __t[sizeof(unsigned long long) / sizeof(__storage_type)];
+ size_t __sz = _Size;
+ for (size_t __i = 0; __i < sizeof(__t) / sizeof(__t[0]); ++__i, __v >>= __bits_per_word, __sz -= __bits_per_word)
+ if (__sz < __bits_per_word)
+ __t[__i] = static_cast<__storage_type>(__v) & (1ULL << __sz) - 1;
+ else
+ __t[__i] = static_cast<__storage_type>(__v);
+
+ std::copy(__t, __t + sizeof(__t) / sizeof(__t[0]), __first_);
+ std::fill(
+ __first_ + sizeof(__t) / sizeof(__t[0]), __first_ + sizeof(__first_) / sizeof(__first_[0]), __storage_type(0));
+}
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI void __bitset<_N_words, _Size>::__init(unsigned long long __v, true_type) _NOEXCEPT {
+ __first_[0] = __v;
+ if (_Size < __bits_per_word)
+ __first_[0] &= (1ULL << _Size) - 1;
+
+ std::fill(__first_ + 1, __first_ + sizeof(__first_) / sizeof(__first_[0]), __storage_type(0));
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_CONSTEXPR __bitset<_N_words, _Size>::__bitset(unsigned long long __v) _NOEXCEPT
+#ifndef _LIBCPP_CXX03_LANG
+# if __SIZEOF_SIZE_T__ == 8
+ : __first_{__v}
+# elif __SIZEOF_SIZE_T__ == 4
+ : __first_{static_cast<__storage_type>(__v),
+ _Size >= 2 * __bits_per_word
+ ? static_cast<__storage_type>(__v >> __bits_per_word)
+ : static_cast<__storage_type>((__v >> __bits_per_word) &
+ (__storage_type(1) << (_Size - __bits_per_word)) - 1)}
+# else
+# error This constructor has not been ported to this platform
+# endif
+#endif
+{
+#ifdef _LIBCPP_CXX03_LANG
+ __init(__v, integral_constant<bool, sizeof(unsigned long long) == sizeof(__storage_type)>());
+#endif
+}
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void
+__bitset<_N_words, _Size>::operator&=(const __bitset& __v) _NOEXCEPT {
+ for (size_type __i = 0; __i < _N_words; ++__i)
+ __first_[__i] &= __v.__first_[__i];
+}
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void
+__bitset<_N_words, _Size>::operator|=(const __bitset& __v) _NOEXCEPT {
+ for (size_type __i = 0; __i < _N_words; ++__i)
+ __first_[__i] |= __v.__first_[__i];
+}
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void
+__bitset<_N_words, _Size>::operator^=(const __bitset& __v) _NOEXCEPT {
+ for (size_type __i = 0; __i < _N_words; ++__i)
+ __first_[__i] ^= __v.__first_[__i];
+}
+
+template <size_t _N_words, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void __bitset<_N_words, _Size>::flip() _NOEXCEPT {
+ // do middle whole words
+ size_type __n = _Size;
+ __storage_pointer __p = __first_;
+ for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
+ *__p = ~*__p;
+ // do last partial word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __storage_type __b = *__p & __m;
+ *__p &= ~__m;
+ *__p |= ~__b & __m;
+ }
+}
+
+template <size_t _N_words, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long
+__bitset<_N_words, _Size>::to_ulong(false_type) const {
+ const_iterator __e = __make_iter(_Size);
+ const_iterator __i = std::find(__make_iter(sizeof(unsigned long) * CHAR_BIT), __e, true);
+ if (__i != __e)
+ __throw_overflow_error("bitset to_ulong overflow error");
+
+ return __first_[0];
+}
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long
+__bitset<_N_words, _Size>::to_ulong(true_type) const {
+ return __first_[0];
+}
+
+template <size_t _N_words, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long
+__bitset<_N_words, _Size>::to_ullong(false_type) const {
+ const_iterator __e = __make_iter(_Size);
+ const_iterator __i = std::find(__make_iter(sizeof(unsigned long long) * CHAR_BIT), __e, true);
+ if (__i != __e)
+ __throw_overflow_error("bitset to_ullong overflow error");
+
+ return to_ullong(true_type());
+}
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long
+__bitset<_N_words, _Size>::to_ullong(true_type) const {
+ return to_ullong(true_type(), integral_constant<bool, sizeof(__storage_type) < sizeof(unsigned long long)>());
+}
+
+template <size_t _N_words, size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long
+__bitset<_N_words, _Size>::to_ullong(true_type, false_type) const {
+ return __first_[0];
+}
+
+template <size_t _N_words, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long
+__bitset<_N_words, _Size>::to_ullong(true_type, true_type) const {
+ unsigned long long __r = __first_[0];
+ _LIBCPP_DIAGNOSTIC_PUSH
+ _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wshift-count-overflow")
+ for (size_t __i = 1; __i < sizeof(unsigned long long) / sizeof(__storage_type); ++__i)
+ __r |= static_cast<unsigned long long>(__first_[__i]) << (sizeof(__storage_type) * CHAR_BIT);
+ _LIBCPP_DIAGNOSTIC_POP
+ return __r;
+}
+
+template <size_t _N_words, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool __bitset<_N_words, _Size>::all() const _NOEXCEPT {
+ // do middle whole words
+ size_type __n = _Size;
+ __const_storage_pointer __p = __first_;
+ for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
+ if (~*__p)
+ return false;
+ // do last partial word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ if (~*__p & __m)
+ return false;
+ }
+ return true;
+}
+
+template <size_t _N_words, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool __bitset<_N_words, _Size>::any() const _NOEXCEPT {
+ // do middle whole words
+ size_type __n = _Size;
+ __const_storage_pointer __p = __first_;
+ for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
+ if (*__p)
+ return true;
+ // do last partial word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ if (*__p & __m)
+ return true;
+ }
+ return false;
+}
+
+template <size_t _N_words, size_t _Size>
+inline size_t __bitset<_N_words, _Size>::__hash_code() const _NOEXCEPT {
+ size_t __h = 0;
+ for (size_type __i = 0; __i < _N_words; ++__i)
+ __h ^= __first_[__i];
+ return __h;
+}
+
+template <size_t _Size>
+class __bitset<1, _Size> {
+public:
+ typedef ptrdiff_t difference_type;
+ typedef size_t size_type;
+ typedef size_type __storage_type;
+
+protected:
+ typedef __bitset __self;
+ typedef __storage_type* __storage_pointer;
+ typedef const __storage_type* __const_storage_pointer;
+ static const unsigned __bits_per_word = static_cast<unsigned>(sizeof(__storage_type) * CHAR_BIT);
+
+ friend class __bit_reference<__bitset>;
+ friend class __bit_const_reference<__bitset>;
+ friend class __bit_iterator<__bitset, false>;
+ friend class __bit_iterator<__bitset, true>;
+ friend struct __bit_array<__bitset>;
+
+ __storage_type __first_;
+
+ typedef __bit_reference<__bitset> reference;
+ typedef __bit_const_reference<__bitset> const_reference;
+ typedef __bit_iterator<__bitset, false> iterator;
+ typedef __bit_iterator<__bitset, true> const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __bitset() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI explicit _LIBCPP_CONSTEXPR __bitset(unsigned long long __v) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 reference __make_ref(size_t __pos) _NOEXCEPT {
+ return reference(&__first_, __storage_type(1) << __pos);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference __make_ref(size_t __pos) const _NOEXCEPT {
+ return const_reference(&__first_, __storage_type(1) << __pos);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 iterator __make_iter(size_t __pos) _NOEXCEPT {
+ return iterator(&__first_ + __pos / __bits_per_word, __pos % __bits_per_word);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 const_iterator __make_iter(size_t __pos) const _NOEXCEPT {
+ return const_iterator(&__first_ + __pos / __bits_per_word, __pos % __bits_per_word);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator&=(const __bitset& __v) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator|=(const __bitset& __v) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator^=(const __bitset& __v) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void flip() _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long to_ulong() const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong() const;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool all() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool any() const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI size_t __hash_code() const _NOEXCEPT;
+};
+
+template <size_t _Size>
+inline _LIBCPP_CONSTEXPR __bitset<1, _Size>::__bitset() _NOEXCEPT : __first_(0) {}
+
+template <size_t _Size>
+inline _LIBCPP_CONSTEXPR __bitset<1, _Size>::__bitset(unsigned long long __v) _NOEXCEPT
+ : __first_(_Size == __bits_per_word ? static_cast<__storage_type>(__v)
+ : static_cast<__storage_type>(__v) & ((__storage_type(1) << _Size) - 1)) {}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void
+__bitset<1, _Size>::operator&=(const __bitset& __v) _NOEXCEPT {
+ __first_ &= __v.__first_;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void
+__bitset<1, _Size>::operator|=(const __bitset& __v) _NOEXCEPT {
+ __first_ |= __v.__first_;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void
+__bitset<1, _Size>::operator^=(const __bitset& __v) _NOEXCEPT {
+ __first_ ^= __v.__first_;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void __bitset<1, _Size>::flip() _NOEXCEPT {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - _Size);
+ __first_ = ~__first_;
+ __first_ &= __m;
+}
+
+template <size_t _Size>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long __bitset<1, _Size>::to_ulong() const {
+ return __first_;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long __bitset<1, _Size>::to_ullong() const {
+ return __first_;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool __bitset<1, _Size>::all() const _NOEXCEPT {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - _Size);
+ return !(~__first_ & __m);
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool __bitset<1, _Size>::any() const _NOEXCEPT {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - _Size);
+ return __first_ & __m;
+}
+
+template <size_t _Size>
+inline size_t __bitset<1, _Size>::__hash_code() const _NOEXCEPT {
+ return __first_;
+}
+
+template <>
+class __bitset<0, 0> {
+public:
+ typedef ptrdiff_t difference_type;
+ typedef size_t size_type;
+ typedef size_type __storage_type;
+
+protected:
+ typedef __bitset __self;
+ typedef __storage_type* __storage_pointer;
+ typedef const __storage_type* __const_storage_pointer;
+ static const unsigned __bits_per_word = static_cast<unsigned>(sizeof(__storage_type) * CHAR_BIT);
+
+ friend class __bit_reference<__bitset>;
+ friend class __bit_const_reference<__bitset>;
+ friend class __bit_iterator<__bitset, false>;
+ friend class __bit_iterator<__bitset, true>;
+ friend struct __bit_array<__bitset>;
+
+ typedef __bit_reference<__bitset> reference;
+ typedef __bit_const_reference<__bitset> const_reference;
+ typedef __bit_iterator<__bitset, false> iterator;
+ typedef __bit_iterator<__bitset, true> const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __bitset() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI explicit _LIBCPP_CONSTEXPR __bitset(unsigned long long) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 reference __make_ref(size_t) _NOEXCEPT {
+ return reference(nullptr, 1);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference __make_ref(size_t) const _NOEXCEPT {
+ return const_reference(nullptr, 1);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 iterator __make_iter(size_t) _NOEXCEPT {
+ return iterator(nullptr, 0);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 const_iterator __make_iter(size_t) const _NOEXCEPT {
+ return const_iterator(nullptr, 0);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator&=(const __bitset&) _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator|=(const __bitset&) _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator^=(const __bitset&) _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void flip() _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long to_ulong() const { return 0; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong() const { return 0; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool all() const _NOEXCEPT { return true; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool any() const _NOEXCEPT { return false; }
+
+ _LIBCPP_HIDE_FROM_ABI size_t __hash_code() const _NOEXCEPT { return 0; }
+};
+
+inline _LIBCPP_CONSTEXPR __bitset<0, 0>::__bitset() _NOEXCEPT {}
+
+inline _LIBCPP_CONSTEXPR __bitset<0, 0>::__bitset(unsigned long long) _NOEXCEPT {}
+
+template <size_t _Size>
+class _LIBCPP_TEMPLATE_VIS bitset;
+template <size_t _Size>
+struct hash<bitset<_Size> >;
+
+template <size_t _Size>
+class _LIBCPP_TEMPLATE_VIS bitset
+ : private __bitset<_Size == 0 ? 0 : (_Size - 1) / (sizeof(size_t) * CHAR_BIT) + 1, _Size> {
+public:
+ static const unsigned __n_words = _Size == 0 ? 0 : (_Size - 1) / (sizeof(size_t) * CHAR_BIT) + 1;
+ typedef __bitset<__n_words, _Size> base;
+
+public:
+ typedef typename base::reference reference;
+ typedef typename base::const_reference const_reference;
+
+ // 23.3.5.1 constructors:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bitset() _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bitset(unsigned long long __v) _NOEXCEPT : base(__v) {}
+ template <class _CharT, __enable_if_t<_IsCharLikeType<_CharT>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit bitset(
+ const _CharT* __str,
+#if _LIBCPP_STD_VER >= 26
+ typename basic_string_view<_CharT>::size_type __n = basic_string_view<_CharT>::npos,
+#else
+ typename basic_string<_CharT>::size_type __n = basic_string<_CharT>::npos,
+#endif
+ _CharT __zero = _CharT('0'),
+ _CharT __one = _CharT('1')) {
+
+ size_t __rlen = std::min(__n, char_traits<_CharT>::length(__str));
+ __init_from_string_view(basic_string_view<_CharT>(__str, __rlen), __zero, __one);
+ }
+#if _LIBCPP_STD_VER >= 26
+ template <class _CharT, class _Traits>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit bitset(
+ basic_string_view<_CharT, _Traits> __str,
+ typename basic_string_view<_CharT, _Traits>::size_type __pos = 0,
+ typename basic_string_view<_CharT, _Traits>::size_type __n = basic_string_view<_CharT, _Traits>::npos,
+ _CharT __zero = _CharT('0'),
+ _CharT __one = _CharT('1')) {
+ if (__pos > __str.size())
+ __throw_out_of_range("bitset string pos out of range");
+
+ size_t __rlen = std::min(__n, __str.size() - __pos);
+ __init_from_string_view(basic_string_view<_CharT, _Traits>(__str.data() + __pos, __rlen), __zero, __one);
+ }
+#endif
+ template <class _CharT, class _Traits, class _Allocator>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit bitset(
+ const basic_string<_CharT, _Traits, _Allocator>& __str,
+ typename basic_string<_CharT, _Traits, _Allocator>::size_type __pos = 0,
+ typename basic_string<_CharT, _Traits, _Allocator>::size_type __n =
+ basic_string<_CharT, _Traits, _Allocator>::npos,
+ _CharT __zero = _CharT('0'),
+ _CharT __one = _CharT('1')) {
+ if (__pos > __str.size())
+ std::__throw_out_of_range("bitset string pos out of range");
+
+ size_t __rlen = std::min(__n, __str.size() - __pos);
+ __init_from_string_view(basic_string_view<_CharT, _Traits>(__str.data() + __pos, __rlen), __zero, __one);
+ }
+
+ // 23.3.5.2 bitset operations:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& operator&=(const bitset& __rhs) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& operator|=(const bitset& __rhs) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& operator^=(const bitset& __rhs) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& operator<<=(size_t __pos) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& operator>>=(size_t __pos) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& set() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& set(size_t __pos, bool __val = true);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& reset() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& reset(size_t __pos);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset operator~() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& flip() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset& flip(size_t __pos);
+
+ // element access:
+#ifdef _LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool operator[](size_t __p) const { return base::__make_ref(__p); }
+#else
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference operator[](size_t __p) const { return base::__make_ref(__p); }
+#endif
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 reference operator[](size_t __p) { return base::__make_ref(__p); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long to_ulong() const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong() const;
+ template <class _CharT, class _Traits, class _Allocator>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 basic_string<_CharT, _Traits, _Allocator>
+ to_string(_CharT __zero = _CharT('0'), _CharT __one = _CharT('1')) const;
+ template <class _CharT, class _Traits>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 basic_string<_CharT, _Traits, allocator<_CharT> >
+ to_string(_CharT __zero = _CharT('0'), _CharT __one = _CharT('1')) const;
+ template <class _CharT>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 basic_string<_CharT, char_traits<_CharT>, allocator<_CharT> >
+ to_string(_CharT __zero = _CharT('0'), _CharT __one = _CharT('1')) const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 basic_string<char, char_traits<char>, allocator<char> >
+ to_string(char __zero = '0', char __one = '1') const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 size_t count() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_t size() const _NOEXCEPT { return _Size; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator==(const bitset& __rhs) const _NOEXCEPT;
+#if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(const bitset& __rhs) const _NOEXCEPT;
+#endif
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool test(size_t __pos) const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool all() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool any() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool none() const _NOEXCEPT { return !any(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset operator<<(size_t __pos) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset operator>>(size_t __pos) const _NOEXCEPT;
+
+private:
+ template <class _CharT, class _Traits>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void
+ __init_from_string_view(basic_string_view<_CharT, _Traits> __str, _CharT __zero, _CharT __one) {
+ for (size_t __i = 0; __i < __str.size(); ++__i)
+ if (!_Traits::eq(__str[__i], __zero) && !_Traits::eq(__str[__i], __one))
+ std::__throw_invalid_argument("bitset string ctor has invalid argument");
+
+ size_t __mp = std::min(__str.size(), _Size);
+ size_t __i = 0;
+ for (; __i < __mp; ++__i) {
+ _CharT __c = __str[__mp - 1 - __i];
+ (*this)[__i] = _Traits::eq(__c, __one);
+ }
+ std::fill(base::__make_iter(__i), base::__make_iter(_Size), false);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_t __hash_code() const _NOEXCEPT { return base::__hash_code(); }
+
+ friend struct hash<bitset>;
+};
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>&
+bitset<_Size>::operator&=(const bitset& __rhs) _NOEXCEPT {
+ base::operator&=(__rhs);
+ return *this;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>&
+bitset<_Size>::operator|=(const bitset& __rhs) _NOEXCEPT {
+ base::operator|=(__rhs);
+ return *this;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>&
+bitset<_Size>::operator^=(const bitset& __rhs) _NOEXCEPT {
+ base::operator^=(__rhs);
+ return *this;
+}
+
+template <size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>& bitset<_Size>::operator<<=(size_t __pos) _NOEXCEPT {
+ __pos = std::min(__pos, _Size);
+ std::copy_backward(base::__make_iter(0), base::__make_iter(_Size - __pos), base::__make_iter(_Size));
+ std::fill_n(base::__make_iter(0), __pos, false);
+ return *this;
+}
+
+template <size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>& bitset<_Size>::operator>>=(size_t __pos) _NOEXCEPT {
+ __pos = std::min(__pos, _Size);
+ std::copy(base::__make_iter(__pos), base::__make_iter(_Size), base::__make_iter(0));
+ std::fill_n(base::__make_iter(_Size - __pos), __pos, false);
+ return *this;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>& bitset<_Size>::set() _NOEXCEPT {
+ std::fill_n(base::__make_iter(0), _Size, true);
+ return *this;
+}
+
+template <size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>& bitset<_Size>::set(size_t __pos, bool __val) {
+ if (__pos >= _Size)
+ __throw_out_of_range("bitset set argument out of range");
+
+ (*this)[__pos] = __val;
+ return *this;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>& bitset<_Size>::reset() _NOEXCEPT {
+ std::fill_n(base::__make_iter(0), _Size, false);
+ return *this;
+}
+
+template <size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>& bitset<_Size>::reset(size_t __pos) {
+ if (__pos >= _Size)
+ __throw_out_of_range("bitset reset argument out of range");
+
+ (*this)[__pos] = false;
+ return *this;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size> bitset<_Size>::operator~() const _NOEXCEPT {
+ bitset __x(*this);
+ __x.flip();
+ return __x;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>& bitset<_Size>::flip() _NOEXCEPT {
+ base::flip();
+ return *this;
+}
+
+template <size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>& bitset<_Size>::flip(size_t __pos) {
+ if (__pos >= _Size)
+ __throw_out_of_range("bitset flip argument out of range");
+
+ reference __r = base::__make_ref(__pos);
+ __r = ~__r;
+ return *this;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long bitset<_Size>::to_ulong() const {
+ return base::to_ulong();
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long bitset<_Size>::to_ullong() const {
+ return base::to_ullong();
+}
+
+template <size_t _Size>
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 basic_string<_CharT, _Traits, _Allocator>
+bitset<_Size>::to_string(_CharT __zero, _CharT __one) const {
+ basic_string<_CharT, _Traits, _Allocator> __r(_Size, __zero);
+ for (size_t __i = 0; __i != _Size; ++__i) {
+ if ((*this)[__i])
+ __r[_Size - 1 - __i] = __one;
+ }
+ return __r;
+}
+
+template <size_t _Size>
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 basic_string<_CharT, _Traits, allocator<_CharT> >
+bitset<_Size>::to_string(_CharT __zero, _CharT __one) const {
+ return to_string<_CharT, _Traits, allocator<_CharT> >(__zero, __one);
+}
+
+template <size_t _Size>
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 basic_string<_CharT, char_traits<_CharT>, allocator<_CharT> >
+bitset<_Size>::to_string(_CharT __zero, _CharT __one) const {
+ return to_string<_CharT, char_traits<_CharT>, allocator<_CharT> >(__zero, __one);
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 basic_string<char, char_traits<char>, allocator<char> >
+bitset<_Size>::to_string(char __zero, char __one) const {
+ return to_string<char, char_traits<char>, allocator<char> >(__zero, __one);
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 size_t bitset<_Size>::count() const _NOEXCEPT {
+ return static_cast<size_t>(std::count(base::__make_iter(0), base::__make_iter(_Size), true));
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
+bitset<_Size>::operator==(const bitset& __rhs) const _NOEXCEPT {
+ return std::equal(base::__make_iter(0), base::__make_iter(_Size), __rhs.__make_iter(0));
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI bool bitset<_Size>::operator!=(const bitset& __rhs) const _NOEXCEPT {
+ return !(*this == __rhs);
+}
+
+#endif
+
+template <size_t _Size>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool bitset<_Size>::test(size_t __pos) const {
+ if (__pos >= _Size)
+ __throw_out_of_range("bitset test argument out of range");
+
+ return (*this)[__pos];
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool bitset<_Size>::all() const _NOEXCEPT {
+ return base::all();
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool bitset<_Size>::any() const _NOEXCEPT {
+ return base::any();
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>
+bitset<_Size>::operator<<(size_t __pos) const _NOEXCEPT {
+ bitset __r = *this;
+ __r <<= __pos;
+ return __r;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>
+bitset<_Size>::operator>>(size_t __pos) const _NOEXCEPT {
+ bitset __r = *this;
+ __r >>= __pos;
+ return __r;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>
+operator&(const bitset<_Size>& __x, const bitset<_Size>& __y) _NOEXCEPT {
+ bitset<_Size> __r = __x;
+ __r &= __y;
+ return __r;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>
+operator|(const bitset<_Size>& __x, const bitset<_Size>& __y) _NOEXCEPT {
+ bitset<_Size> __r = __x;
+ __r |= __y;
+ return __r;
+}
+
+template <size_t _Size>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bitset<_Size>
+operator^(const bitset<_Size>& __x, const bitset<_Size>& __y) _NOEXCEPT {
+ bitset<_Size> __r = __x;
+ __r ^= __y;
+ return __r;
+}
+
+template <size_t _Size>
+struct _LIBCPP_TEMPLATE_VIS hash<bitset<_Size> > : public __unary_function<bitset<_Size>, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const bitset<_Size>& __bs) const _NOEXCEPT { return __bs.__hash_code(); }
+};
+
+template <class _CharT, class _Traits, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, bitset<_Size>& __x);
+
+template <class _CharT, class _Traits, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const bitset<_Size>& __x);
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <cstdlib>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_BITSET
diff --git a/libcxx/include/__cxx03/cassert b/libcxx/include/__cxx03/cassert
new file mode 100644
index 00000000000000..6fec37dc637610
--- /dev/null
+++ b/libcxx/include/__cxx03/cassert
@@ -0,0 +1,31 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+/*
+ cassert synopsis
+
+Macros:
+
+ assert
+
+*/
+
+#include <__config>
+
+// <assert.h> is not provided by libc++
+#if __has_include(<assert.h>)
+# include <assert.h>
+# ifdef _LIBCPP_ASSERT_H
+# error "If libc++ starts defining <assert.h>, the __has_include check should move to libc++'s <assert.h>"
+# endif
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
diff --git a/libcxx/include/__cxx03/ccomplex b/libcxx/include/__cxx03/ccomplex
new file mode 100644
index 00000000000000..94d2c8d7d003d4
--- /dev/null
+++ b/libcxx/include/__cxx03/ccomplex
@@ -0,0 +1,26 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CCOMPLEX
+#define _LIBCPP_CCOMPLEX
+
+/*
+ ccomplex synopsis
+
+#include <complex>
+
+*/
+
+#include <complex>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#endif // _LIBCPP_CCOMPLEX
diff --git a/libcxx/include/__cxx03/cctype b/libcxx/include/__cxx03/cctype
new file mode 100644
index 00000000000000..d7af7e084aa23a
--- /dev/null
+++ b/libcxx/include/__cxx03/cctype
@@ -0,0 +1,127 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CCTYPE
+#define _LIBCPP_CCTYPE
+
+/*
+ cctype synopsis
+
+namespace std
+{
+
+int isalnum(int c);
+int isalpha(int c);
+int isblank(int c); // C99
+int iscntrl(int c);
+int isdigit(int c);
+int isgraph(int c);
+int islower(int c);
+int isprint(int c);
+int ispunct(int c);
+int isspace(int c);
+int isupper(int c);
+int isxdigit(int c);
+int tolower(int c);
+int toupper(int c);
+
+} // std
+*/
+
+#include <__config>
+
+#include <ctype.h>
+
+#ifndef _LIBCPP_CTYPE_H
+# error <cctype> tried including <ctype.h> but didn't find libc++'s <ctype.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifdef isalnum
+# undef isalnum
+#endif
+
+#ifdef isalpha
+# undef isalpha
+#endif
+
+#ifdef isblank
+# undef isblank
+#endif
+
+#ifdef iscntrl
+# undef iscntrl
+#endif
+
+#ifdef isdigit
+# undef isdigit
+#endif
+
+#ifdef isgraph
+# undef isgraph
+#endif
+
+#ifdef islower
+# undef islower
+#endif
+
+#ifdef isprint
+# undef isprint
+#endif
+
+#ifdef ispunct
+# undef ispunct
+#endif
+
+#ifdef isspace
+# undef isspace
+#endif
+
+#ifdef isupper
+# undef isupper
+#endif
+
+#ifdef isxdigit
+# undef isxdigit
+#endif
+
+#ifdef tolower
+# undef tolower
+#endif
+
+#ifdef toupper
+# undef toupper
+#endif
+
+using ::isalnum _LIBCPP_USING_IF_EXISTS;
+using ::isalpha _LIBCPP_USING_IF_EXISTS;
+using ::isblank _LIBCPP_USING_IF_EXISTS;
+using ::iscntrl _LIBCPP_USING_IF_EXISTS;
+using ::isdigit _LIBCPP_USING_IF_EXISTS;
+using ::isgraph _LIBCPP_USING_IF_EXISTS;
+using ::islower _LIBCPP_USING_IF_EXISTS;
+using ::isprint _LIBCPP_USING_IF_EXISTS;
+using ::ispunct _LIBCPP_USING_IF_EXISTS;
+using ::isspace _LIBCPP_USING_IF_EXISTS;
+using ::isupper _LIBCPP_USING_IF_EXISTS;
+using ::isxdigit _LIBCPP_USING_IF_EXISTS;
+using ::tolower _LIBCPP_USING_IF_EXISTS;
+using ::toupper _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CCTYPE
diff --git a/libcxx/include/__cxx03/cerrno b/libcxx/include/__cxx03/cerrno
new file mode 100644
index 00000000000000..f1295680fed6c8
--- /dev/null
+++ b/libcxx/include/__cxx03/cerrno
@@ -0,0 +1,48 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CERRNO
+#define _LIBCPP_CERRNO
+
+/*
+ cerrno synopsis
+
+Macros:
+
+ EDOM
+ EILSEQ // C99
+ ERANGE
+ errno
+
+*/
+
+#include <__config>
+
+#include <errno.h>
+
+#ifndef _LIBCPP_ERRNO_H
+# error <cerrno> tried including <errno.h> but didn't find libc++'s <errno.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// LWG3869 Deprecate std::errc constants related to UNIX STREAMS
+//
+// This LWG issue deprecates the POSIX macros ENODATA, ENOSR, ENOSTR, and ETIME. These were
+// deprecated in libc++ in https://github.com/llvm/llvm-project/pull/80542.
+// Based on the post commit feedback the macro are no longer deprecated.
+// Instead libc++ leaves the deprecation to the provider of errno.h.
+
+#endif // _LIBCPP_CERRNO
diff --git a/libcxx/include/__cxx03/cfenv b/libcxx/include/__cxx03/cfenv
new file mode 100644
index 00000000000000..f8cacd562f76bd
--- /dev/null
+++ b/libcxx/include/__cxx03/cfenv
@@ -0,0 +1,90 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CFENV
+#define _LIBCPP_CFENV
+
+/*
+ cfenv synopsis
+
+This entire header is C99 / C++0X
+
+Macros:
+
+ FE_DIVBYZERO
+ FE_INEXACT
+ FE_INVALID
+ FE_OVERFLOW
+ FE_UNDERFLOW
+ FE_ALL_EXCEPT
+ FE_DOWNWARD
+ FE_TONEAREST
+ FE_TOWARDZERO
+ FE_UPWARD
+ FE_DFL_ENV
+
+namespace std
+{
+
+Types:
+
+ fenv_t
+ fexcept_t
+
+int feclearexcept(int excepts);
+int fegetexceptflag(fexcept_t* flagp, int excepts);
+int feraiseexcept(int excepts);
+int fesetexceptflag(const fexcept_t* flagp, int excepts);
+int fetestexcept(int excepts);
+int fegetround();
+int fesetround(int round);
+int fegetenv(fenv_t* envp);
+int feholdexcept(fenv_t* envp);
+int fesetenv(const fenv_t* envp);
+int feupdateenv(const fenv_t* envp);
+
+} // std
+*/
+
+#include <__config>
+
+#include <fenv.h>
+
+#ifndef _LIBCPP_FENV_H
+# error <cfenv> tried including <fenv.h> but didn't find libc++'s <fenv.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::fenv_t _LIBCPP_USING_IF_EXISTS;
+using ::fexcept_t _LIBCPP_USING_IF_EXISTS;
+
+using ::feclearexcept _LIBCPP_USING_IF_EXISTS;
+using ::fegetexceptflag _LIBCPP_USING_IF_EXISTS;
+using ::feraiseexcept _LIBCPP_USING_IF_EXISTS;
+using ::fesetexceptflag _LIBCPP_USING_IF_EXISTS;
+using ::fetestexcept _LIBCPP_USING_IF_EXISTS;
+using ::fegetround _LIBCPP_USING_IF_EXISTS;
+using ::fesetround _LIBCPP_USING_IF_EXISTS;
+using ::fegetenv _LIBCPP_USING_IF_EXISTS;
+using ::feholdexcept _LIBCPP_USING_IF_EXISTS;
+using ::fesetenv _LIBCPP_USING_IF_EXISTS;
+using ::feupdateenv _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CFENV
diff --git a/libcxx/include/__cxx03/cfloat b/libcxx/include/__cxx03/cfloat
new file mode 100644
index 00000000000000..5d1b38c557dcad
--- /dev/null
+++ b/libcxx/include/__cxx03/cfloat
@@ -0,0 +1,88 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CFLOAT
+#define _LIBCPP_CFLOAT
+
+/*
+ cfloat synopsis
+
+Macros:
+
+ FLT_ROUNDS
+ FLT_EVAL_METHOD // C99
+ FLT_RADIX
+
+ FLT_HAS_SUBNORM // C11
+ DBL_HAS_SUBNORM // C11
+ LDBL_HAS_SUBNORM // C11
+
+ FLT_MANT_DIG
+ DBL_MANT_DIG
+ LDBL_MANT_DIG
+
+ DECIMAL_DIG // C99
+ FLT_DECIMAL_DIG // C11
+ DBL_DECIMAL_DIG // C11
+ LDBL_DECIMAL_DIG // C11
+
+ FLT_DIG
+ DBL_DIG
+ LDBL_DIG
+
+ FLT_MIN_EXP
+ DBL_MIN_EXP
+ LDBL_MIN_EXP
+
+ FLT_MIN_10_EXP
+ DBL_MIN_10_EXP
+ LDBL_MIN_10_EXP
+
+ FLT_MAX_EXP
+ DBL_MAX_EXP
+ LDBL_MAX_EXP
+
+ FLT_MAX_10_EXP
+ DBL_MAX_10_EXP
+ LDBL_MAX_10_EXP
+
+ FLT_MAX
+ DBL_MAX
+ LDBL_MAX
+
+ FLT_EPSILON
+ DBL_EPSILON
+ LDBL_EPSILON
+
+ FLT_MIN
+ DBL_MIN
+ LDBL_MIN
+
+ FLT_TRUE_MIN // C11
+ DBL_TRUE_MIN // C11
+ LDBL_TRUE_MIN // C11
+*/
+
+#include <__config>
+
+#include <float.h>
+
+#ifndef _LIBCPP_FLOAT_H
+# error <cfloat> tried including <float.h> but didn't find libc++'s <float.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#endif // _LIBCPP_CFLOAT
diff --git a/libcxx/include/__cxx03/charconv b/libcxx/include/__cxx03/charconv
new file mode 100644
index 00000000000000..a2e270e9316dc7
--- /dev/null
+++ b/libcxx/include/__cxx03/charconv
@@ -0,0 +1,115 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CHARCONV
+#define _LIBCPP_CHARCONV
+
+/*
+ charconv synopsis
+
+namespace std {
+
+ // floating-point format for primitive numerical conversion
+ enum class chars_format {
+ scientific = unspecified,
+ fixed = unspecified,
+ hex = unspecified,
+ general = fixed | scientific
+ };
+
+ // 23.20.2, primitive numerical output conversion
+ struct to_chars_result {
+ char* ptr;
+ errc ec;
+ friend bool operator==(const to_chars_result&, const to_chars_result&) = default; // since C++20
+ constexpr explicit operator bool() const noexcept { return ec == errc{}; } // since C++26
+ };
+
+ constexpr to_chars_result to_chars(char* first, char* last, see below value,
+ int base = 10); // constexpr since C++23
+ to_chars_result to_chars(char* first, char* last, bool value,
+ int base = 10) = delete;
+
+ to_chars_result to_chars(char* first, char* last, float value);
+ to_chars_result to_chars(char* first, char* last, double value);
+ to_chars_result to_chars(char* first, char* last, long double value);
+
+ to_chars_result to_chars(char* first, char* last, float value,
+ chars_format fmt);
+ to_chars_result to_chars(char* first, char* last, double value,
+ chars_format fmt);
+ to_chars_result to_chars(char* first, char* last, long double value,
+ chars_format fmt);
+
+ to_chars_result to_chars(char* first, char* last, float value,
+ chars_format fmt, int precision);
+ to_chars_result to_chars(char* first, char* last, double value,
+ chars_format fmt, int precision);
+ to_chars_result to_chars(char* first, char* last, long double value,
+ chars_format fmt, int precision);
+
+ // 23.20.3, primitive numerical input conversion
+ struct from_chars_result {
+ const char* ptr;
+ errc ec;
+ friend bool operator==(const from_chars_result&, const from_chars_result&) = default; // since C++20
+ constexpr explicit operator bool() const noexcept { return ec == errc{}; } // since C++26
+ };
+
+ constexpr from_chars_result from_chars(const char* first, const char* last,
+ see below& value, int base = 10); // constexpr since C++23
+
+} // namespace std
+
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 17
+# include <__charconv/chars_format.h>
+# include <__charconv/from_chars_integral.h>
+# include <__charconv/from_chars_result.h>
+# include <__charconv/tables.h>
+# include <__charconv/to_chars.h>
+# include <__charconv/to_chars_base_10.h>
+# include <__charconv/to_chars_floating_point.h>
+# include <__charconv/to_chars_integral.h>
+# include <__charconv/to_chars_result.h>
+# include <__charconv/traits.h>
+#endif // _LIBCPP_STD_VER >= 17
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 14
+# include <cerrno>
+# include <cstddef>
+# include <initializer_list>
+# include <new>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cmath>
+# include <concepts>
+# include <cstdint>
+# include <cstdlib>
+# include <cstring>
+# include <iosfwd>
+# include <limits>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_CHARCONV
diff --git a/libcxx/include/__cxx03/chrono b/libcxx/include/__cxx03/chrono
new file mode 100644
index 00000000000000..7bec5e5a26ef4a
--- /dev/null
+++ b/libcxx/include/__cxx03/chrono
@@ -0,0 +1,1022 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CHRONO
+#define _LIBCPP_CHRONO
+
+// clang-format off
+
+/*
+ chrono synopsis
+
+#include <compare> // C++20
+
+namespace std
+{
+namespace chrono
+{
+
+template <class ToDuration, class Rep, class Period>
+constexpr
+ToDuration
+duration_cast(const duration<Rep, Period>& fd);
+
+template <class Rep> struct treat_as_floating_point : is_floating_point<Rep> {};
+
+template <class Rep> inline constexpr bool treat_as_floating_point_v
+ = treat_as_floating_point<Rep>::value; // C++17
+
+template <class Rep>
+struct duration_values
+{
+public:
+ static constexpr Rep zero(); // noexcept in C++20
+ static constexpr Rep max(); // noexcept in C++20
+ static constexpr Rep min(); // noexcept in C++20
+};
+
+// duration
+
+template <class Rep, class Period = ratio<1>>
+class duration
+{
+ static_assert(!__is_duration<Rep>::value, "A duration representation can not be a duration");
+ static_assert(__is_ratio<Period>::value, "Second template parameter of duration must be a std::ratio");
+ static_assert(Period::num > 0, "duration period must be positive");
+public:
+ typedef Rep rep;
+ typedef typename _Period::type period;
+
+ constexpr duration() = default;
+ template <class Rep2>
+ constexpr explicit duration(const Rep2& r,
+ typename enable_if
+ <
+ is_convertible<const Rep2&, rep>::value &&
+ (treat_as_floating_point<rep>::value ||
+ !treat_as_floating_point<rep>::value && !treat_as_floating_point<Rep2>::value)
+ >::type* = 0);
+
+ // conversions
+ template <class Rep2, class Period2>
+ constexpr duration(const duration<Rep2, Period2>& d,
+ typename enable_if
+ <
+ treat_as_floating_point<rep>::value ||
+ ratio_divide<Period2, period>::type::den == 1
+ >::type* = 0);
+
+ // observer
+
+ constexpr rep count() const;
+
+ // arithmetic
+
+ constexpr common_type<duration>::type operator+() const;
+ constexpr common_type<duration>::type operator-() const;
+ constexpr duration& operator++(); // constexpr in C++17
+ constexpr duration operator++(int); // constexpr in C++17
+ constexpr duration& operator--(); // constexpr in C++17
+ constexpr duration operator--(int); // constexpr in C++17
+
+ constexpr duration& operator+=(const duration& d); // constexpr in C++17
+ constexpr duration& operator-=(const duration& d); // constexpr in C++17
+
+ duration& operator*=(const rep& rhs); // constexpr in C++17
+ duration& operator/=(const rep& rhs); // constexpr in C++17
+ duration& operator%=(const rep& rhs); // constexpr in C++17
+ duration& operator%=(const duration& rhs); // constexpr in C++17
+
+ // special values
+
+ static constexpr duration zero(); // noexcept in C++20
+ static constexpr duration min(); // noexcept in C++20
+ static constexpr duration max(); // noexcept in C++20
+};
+
+typedef duration<long long, nano> nanoseconds;
+typedef duration<long long, micro> microseconds;
+typedef duration<long long, milli> milliseconds;
+typedef duration<long long > seconds;
+typedef duration< long, ratio< 60> > minutes;
+typedef duration< long, ratio<3600> > hours;
+
+template <class Clock, class Duration = typename Clock::duration>
+class time_point
+{
+public:
+ typedef Clock clock;
+ typedef Duration duration;
+ typedef typename duration::rep rep;
+ typedef typename duration::period period;
+private:
+ duration d_; // exposition only
+
+public:
+ time_point(); // has value "epoch" // constexpr in C++14
+ explicit time_point(const duration& d); // same as time_point() + d // constexpr in C++14
+
+ // conversions
+ template <class Duration2>
+ time_point(const time_point<clock, Duration2>& t); // constexpr in C++14
+
+ // observer
+
+ duration time_since_epoch() const; // constexpr in C++14
+
+ // arithmetic
+
+ time_point& operator+=(const duration& d); // constexpr in C++17
+ time_point& operator-=(const duration& d); // constexpr in C++17
+
+ // special values
+
+ static constexpr time_point min(); // noexcept in C++20
+ static constexpr time_point max(); // noexcept in C++20
+};
+
+} // chrono
+
+// common_type traits
+template <class Rep1, class Period1, class Rep2, class Period2>
+ struct common_type<chrono::duration<Rep1, Period1>, chrono::duration<Rep2, Period2>>;
+
+template <class Clock, class Duration1, class Duration2>
+ struct common_type<chrono::time_point<Clock, Duration1>, chrono::time_point<Clock, Duration2>>;
+
+namespace chrono {
+
+// duration arithmetic
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2>>::type
+ operator+(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2>>::type
+ operator-(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
+template <class Rep1, class Period, class Rep2>
+ constexpr
+ duration<typename common_type<Rep1, Rep2>::type, Period>
+ operator*(const duration<Rep1, Period>& d, const Rep2& s);
+template <class Rep1, class Period, class Rep2>
+ constexpr
+ duration<typename common_type<Rep1, Rep2>::type, Period>
+ operator*(const Rep1& s, const duration<Rep2, Period>& d);
+template <class Rep1, class Period, class Rep2>
+ constexpr
+ duration<typename common_type<Rep1, Rep2>::type, Period>
+ operator/(const duration<Rep1, Period>& d, const Rep2& s);
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ typename common_type<Rep1, Rep2>::type
+ operator/(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
+
+// duration comparisons
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ bool operator==(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ bool operator!=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs); // removed in C++20
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ bool operator< (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ bool operator<=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ bool operator> (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
+template <class Rep1, class Period1, class Rep2, class Period2>
+ constexpr
+ bool operator>=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
+template<class Rep1, class Period1, class Rep2, class Period2>
+ requires three_way_comparable<typename CT::rep>
+ constexpr auto operator<=>(const duration<Rep1, Period1>& lhs,
+ const duration<Rep2, Period2>& rhs); // since C++20
+
+// duration_cast
+template <class ToDuration, class Rep, class Period>
+ ToDuration duration_cast(const duration<Rep, Period>& d);
+
+template <class ToDuration, class Rep, class Period>
+ constexpr ToDuration floor(const duration<Rep, Period>& d); // C++17
+template <class ToDuration, class Rep, class Period>
+ constexpr ToDuration ceil(const duration<Rep, Period>& d); // C++17
+template <class ToDuration, class Rep, class Period>
+ constexpr ToDuration round(const duration<Rep, Period>& d); // C++17
+
+// duration I/O
+template<class charT, class traits, class Rep, class Period> // C++20
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const duration<Rep, Period>& d);
+
+// time_point arithmetic (all constexpr in C++14)
+template <class Clock, class Duration1, class Rep2, class Period2>
+ time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2>>::type>
+ operator+(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
+template <class Rep1, class Period1, class Clock, class Duration2>
+ time_point<Clock, typename common_type<duration<Rep1, Period1>, Duration2>::type>
+ operator+(const duration<Rep1, Period1>& lhs, const time_point<Clock, Duration2>& rhs);
+template <class Clock, class Duration1, class Rep2, class Period2>
+ time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2>>::type>
+ operator-(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
+template <class Clock, class Duration1, class Duration2>
+ typename common_type<Duration1, Duration2>::type
+ operator-(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
+
+// time_point comparisons (all constexpr in C++14)
+template <class Clock, class Duration1, class Duration2>
+ bool operator==(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
+template <class Clock, class Duration1, class Duration2>
+ bool operator!=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs); // removed in C++20
+template <class Clock, class Duration1, class Duration2>
+ bool operator< (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
+template <class Clock, class Duration1, class Duration2>
+ bool operator<=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
+template <class Clock, class Duration1, class Duration2>
+ bool operator> (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
+template <class Clock, class Duration1, class Duration2>
+ bool operator>=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
+template<class Clock, class Duration1,
+ three_way_comparable_with<Duration1> Duration2>
+ constexpr auto operator<=>(const time_point<Clock, Duration1>& lhs,
+ const time_point<Clock, Duration2>& rhs); // since C++20
+
+// time_point_cast (constexpr in C++14)
+
+template <class ToDuration, class Clock, class Duration>
+ time_point<Clock, ToDuration> time_point_cast(const time_point<Clock, Duration>& t);
+
+template <class ToDuration, class Clock, class Duration>
+ constexpr time_point<Clock, ToDuration>
+ floor(const time_point<Clock, Duration>& tp); // C++17
+
+template <class ToDuration, class Clock, class Duration>
+ constexpr time_point<Clock, ToDuration>
+ ceil(const time_point<Clock, Duration>& tp); // C++17
+
+template <class ToDuration, class Clock, class Duration>
+ constexpr time_point<Clock, ToDuration>
+ round(const time_point<Clock, Duration>& tp); // C++17
+
+template <class Rep, class Period>
+ constexpr duration<Rep, Period> abs(duration<Rep, Period> d); // C++17
+
+// Clocks
+
+class system_clock
+{
+public:
+ typedef microseconds duration;
+ typedef duration::rep rep;
+ typedef duration::period period;
+ typedef chrono::time_point<system_clock> time_point;
+ static const bool is_steady = false; // constexpr in C++14
+
+ static time_point now() noexcept;
+ static time_t to_time_t (const time_point& __t) noexcept;
+ static time_point from_time_t(time_t __t) noexcept;
+};
+
+template <class Duration>
+ using sys_time = time_point<system_clock, Duration>; // C++20
+using sys_seconds = sys_time<seconds>; // C++20
+using sys_days = sys_time<days>; // C++20
+
+template<class charT, class traits, class Duration> // C++20
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const sys_time<Duration>& tp);
+
+template<class charT, class traits> // C++20
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const sys_days& dp);
+
+class file_clock // C++20
+{
+public:
+ typedef see-below rep;
+ typedef nano period;
+ typedef chrono::duration<rep, period> duration;
+ typedef chrono::time_point<file_clock> time_point;
+ static constexpr bool is_steady = false;
+
+ static time_point now() noexcept;
+
+ template<class Duration>
+ static sys_time<see-below> to_sys(const file_time<Duration>&);
+
+ template<class Duration>
+ static file_time<see-below> from_sys(const sys_time<Duration>&);
+};
+
+template<class Duration>
+ using file_time = time_point<file_clock, Duration>; // C++20
+
+template<class charT, class traits, class Duration> // C++20
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const file_time<Duration>& tp);
+
+class steady_clock
+{
+public:
+ typedef nanoseconds duration;
+ typedef duration::rep rep;
+ typedef duration::period period;
+ typedef chrono::time_point<steady_clock, duration> time_point;
+ static const bool is_steady = true; // constexpr in C++14
+
+ static time_point now() noexcept;
+};
+
+typedef steady_clock high_resolution_clock;
+
+// 25.7.8, local time // C++20
+struct local_t {};
+template<class Duration>
+ using local_time = time_point<local_t, Duration>;
+using local_seconds = local_time<seconds>;
+using local_days = local_time<days>;
+
+template<class charT, class traits, class Duration> // C++20
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const local_time<Duration>& tp);
+
+// 25.8.2, class last_spec // C++20
+struct last_spec;
+
+// 25.8.3, class day // C++20
+
+class day;
+constexpr bool operator==(const day& x, const day& y) noexcept;
+constexpr strong_ordering operator<=>(const day& x, const day& y) noexcept;
+constexpr day operator+(const day& x, const days& y) noexcept;
+constexpr day operator+(const days& x, const day& y) noexcept;
+constexpr day operator-(const day& x, const days& y) noexcept;
+constexpr days operator-(const day& x, const day& y) noexcept;
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const day& d);
+
+// 25.8.4, class month // C++20
+class month;
+constexpr bool operator==(const month& x, const month& y) noexcept;
+constexpr strong_ordering operator<=>(const month& x, const month& y) noexcept;
+
+constexpr month operator+(const month& x, const months& y) noexcept;
+constexpr month operator+(const months& x, const month& y) noexcept;
+constexpr month operator-(const month& x, const months& y) noexcept;
+constexpr months operator-(const month& x, const month& y) noexcept;
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const month& m);
+
+// 25.8.5, class year // C++20
+class year;
+constexpr bool operator==(const year& x, const year& y) noexcept;
+constexpr strong_ordering operator<=>(const year& x, const year& y) noexcept;
+
+constexpr year operator+(const year& x, const years& y) noexcept;
+constexpr year operator+(const years& x, const year& y) noexcept;
+constexpr year operator-(const year& x, const years& y) noexcept;
+constexpr years operator-(const year& x, const year& y) noexcept;
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const year& y);
+
+// 25.8.6, class weekday // C++20
+class weekday;
+
+constexpr bool operator==(const weekday& x, const weekday& y) noexcept;
+constexpr weekday operator+(const weekday& x, const days& y) noexcept;
+constexpr weekday operator+(const days& x, const weekday& y) noexcept;
+constexpr weekday operator-(const weekday& x, const days& y) noexcept;
+constexpr days operator-(const weekday& x, const weekday& y) noexcept;
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const weekday& wd);
+
+// 25.8.7, class weekday_indexed // C++20
+
+class weekday_indexed;
+constexpr bool operator==(const weekday_indexed& x, const weekday_indexed& y) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const weekday_indexed& wdi);
+
+// 25.8.8, class weekday_last // C++20
+class weekday_last;
+
+constexpr bool operator==(const weekday_last& x, const weekday_last& y) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const weekday_last& wdl);
+
+// 25.8.9, class month_day // C++20
+class month_day;
+
+constexpr bool operator==(const month_day& x, const month_day& y) noexcept;
+constexpr strong_ordering operator<=>(const month_day& x, const month_day& y) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const month_day& md);
+
+// 25.8.10, class month_day_last // C++20
+class month_day_last;
+
+constexpr bool operator==(const month_day_last& x, const month_day_last& y) noexcept;
+constexpr strong_ordering operator<=>(const month_day_last& x, const month_day_last& y) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const month_day_last& mdl);
+
+// 25.8.11, class month_weekday // C++20
+class month_weekday;
+
+constexpr bool operator==(const month_weekday& x, const month_weekday& y) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const month_weekday& mwd);
+
+// 25.8.12, class month_weekday_last // C++20
+class month_weekday_last;
+
+constexpr bool operator==(const month_weekday_last& x, const month_weekday_last& y) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const month_weekday_last& mwdl);
+
+
+// 25.8.13, class year_month // C++20
+class year_month;
+
+constexpr bool operator==(const year_month& x, const year_month& y) noexcept;
+constexpr strong_ordering operator<=>(const year_month& x, const year_month& y) noexcept;
+
+constexpr year_month operator+(const year_month& ym, const months& dm) noexcept;
+constexpr year_month operator+(const months& dm, const year_month& ym) noexcept;
+constexpr year_month operator-(const year_month& ym, const months& dm) noexcept;
+constexpr months operator-(const year_month& x, const year_month& y) noexcept;
+constexpr year_month operator+(const year_month& ym, const years& dy) noexcept;
+constexpr year_month operator+(const years& dy, const year_month& ym) noexcept;
+constexpr year_month operator-(const year_month& ym, const years& dy) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const year_month& ym);
+
+// 25.8.14, class year_month_day class // C++20
+year_month_day;
+
+constexpr bool operator==(const year_month_day& x, const year_month_day& y) noexcept;
+constexpr strong_ordering operator<=>(const year_month_day& x, const year_month_day& y) noexcept;
+
+constexpr year_month_day operator+(const year_month_day& ymd, const months& dm) noexcept;
+constexpr year_month_day operator+(const months& dm, const year_month_day& ymd) noexcept;
+constexpr year_month_day operator+(const year_month_day& ymd, const years& dy) noexcept;
+constexpr year_month_day operator+(const years& dy, const year_month_day& ymd) noexcept;
+constexpr year_month_day operator-(const year_month_day& ymd, const months& dm) noexcept;
+constexpr year_month_day operator-(const year_month_day& ymd, const years& dy) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const year_month_day& ymd);
+
+// 25.8.15, class year_month_day_last // C++20
+class year_month_day_last;
+
+constexpr bool operator==(const year_month_day_last& x, const year_month_day_last& y) noexcept;
+constexpr strong_ordering operator<=>(const year_month_day_last_day& x, const year_month_day_last_day& y) noexcept;
+
+constexpr year_month_day_last
+ operator+(const year_month_day_last& ymdl, const months& dm) noexcept;
+constexpr year_month_day_last
+ operator+(const months& dm, const year_month_day_last& ymdl) noexcept;
+constexpr year_month_day_last
+ operator+(const year_month_day_last& ymdl, const years& dy) noexcept;
+constexpr year_month_day_last
+ operator+(const years& dy, const year_month_day_last& ymdl) noexcept;
+constexpr year_month_day_last
+ operator-(const year_month_day_last& ymdl, const months& dm) noexcept;
+constexpr year_month_day_last
+ operator-(const year_month_day_last& ymdl, const years& dy) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const year_month_day_last& ymdl);
+
+// 25.8.16, class year_month_weekday // C++20
+class year_month_weekday;
+
+constexpr bool operator==(const year_month_weekday& x,
+ const year_month_weekday& y) noexcept;
+
+constexpr year_month_weekday
+ operator+(const year_month_weekday& ymwd, const months& dm) noexcept;
+constexpr year_month_weekday
+ operator+(const months& dm, const year_month_weekday& ymwd) noexcept;
+constexpr year_month_weekday
+ operator+(const year_month_weekday& ymwd, const years& dy) noexcept;
+constexpr year_month_weekday
+ operator+(const years& dy, const year_month_weekday& ymwd) noexcept;
+constexpr year_month_weekday
+ operator-(const year_month_weekday& ymwd, const months& dm) noexcept;
+constexpr year_month_weekday
+ operator-(const year_month_weekday& ymwd, const years& dy) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const year_month_weekday& ymwd);
+
+// 25.8.17, class year_month_weekday_last // C++20
+class year_month_weekday_last;
+
+constexpr bool operator==(const year_month_weekday_last& x,
+ const year_month_weekday_last& y) noexcept;
+constexpr year_month_weekday_last
+ operator+(const year_month_weekday_last& ymwdl, const months& dm) noexcept;
+constexpr year_month_weekday_last
+ operator+(const months& dm, const year_month_weekday_last& ymwdl) noexcept;
+constexpr year_month_weekday_last
+ operator+(const year_month_weekday_last& ymwdl, const years& dy) noexcept;
+constexpr year_month_weekday_last
+ operator+(const years& dy, const year_month_weekday_last& ymwdl) noexcept;
+constexpr year_month_weekday_last
+ operator-(const year_month_weekday_last& ymwdl, const months& dm) noexcept;
+constexpr year_month_weekday_last
+ operator-(const year_month_weekday_last& ymwdl, const years& dy) noexcept;
+
+template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const year_month_weekday_last& ymwdl);
+
+// 25.8.18, civil calendar conventional syntax operators // C++20
+constexpr year_month
+ operator/(const year& y, const month& m) noexcept;
+constexpr year_month
+ operator/(const year& y, int m) noexcept;
+constexpr month_day
+ operator/(const month& m, const day& d) noexcept;
+constexpr month_day
+ operator/(const month& m, int d) noexcept;
+constexpr month_day
+ operator/(int m, const day& d) noexcept;
+constexpr month_day
+ operator/(const day& d, const month& m) noexcept;
+constexpr month_day
+ operator/(const day& d, int m) noexcept;
+constexpr month_day_last
+ operator/(const month& m, last_spec) noexcept;
+constexpr month_day_last
+ operator/(int m, last_spec) noexcept;
+constexpr month_day_last
+ operator/(last_spec, const month& m) noexcept;
+constexpr month_day_last
+ operator/(last_spec, int m) noexcept;
+constexpr month_weekday
+ operator/(const month& m, const weekday_indexed& wdi) noexcept;
+constexpr month_weekday
+ operator/(int m, const weekday_indexed& wdi) noexcept;
+constexpr month_weekday
+ operator/(const weekday_indexed& wdi, const month& m) noexcept;
+constexpr month_weekday
+ operator/(const weekday_indexed& wdi, int m) noexcept;
+constexpr month_weekday_last
+ operator/(const month& m, const weekday_last& wdl) noexcept;
+constexpr month_weekday_last
+ operator/(int m, const weekday_last& wdl) noexcept;
+constexpr month_weekday_last
+ operator/(const weekday_last& wdl, const month& m) noexcept;
+constexpr month_weekday_last
+ operator/(const weekday_last& wdl, int m) noexcept;
+constexpr year_month_day
+ operator/(const year_month& ym, const day& d) noexcept;
+constexpr year_month_day
+ operator/(const year_month& ym, int d) noexcept;
+constexpr year_month_day
+ operator/(const year& y, const month_day& md) noexcept;
+constexpr year_month_day
+ operator/(int y, const month_day& md) noexcept;
+constexpr year_month_day
+ operator/(const month_day& md, const year& y) noexcept;
+constexpr year_month_day
+ operator/(const month_day& md, int y) noexcept;
+constexpr year_month_day_last
+ operator/(const year_month& ym, last_spec) noexcept;
+constexpr year_month_day_last
+ operator/(const year& y, const month_day_last& mdl) noexcept;
+constexpr year_month_day_last
+ operator/(int y, const month_day_last& mdl) noexcept;
+constexpr year_month_day_last
+ operator/(const month_day_last& mdl, const year& y) noexcept;
+constexpr year_month_day_last
+ operator/(const month_day_last& mdl, int y) noexcept;
+constexpr year_month_weekday
+ operator/(const year_month& ym, const weekday_indexed& wdi) noexcept;
+constexpr year_month_weekday
+ operator/(const year& y, const month_weekday& mwd) noexcept;
+constexpr year_month_weekday
+ operator/(int y, const month_weekday& mwd) noexcept;
+constexpr year_month_weekday
+ operator/(const month_weekday& mwd, const year& y) noexcept;
+constexpr year_month_weekday
+ operator/(const month_weekday& mwd, int y) noexcept;
+constexpr year_month_weekday_last
+ operator/(const year_month& ym, const weekday_last& wdl) noexcept;
+constexpr year_month_weekday_last
+ operator/(const year& y, const month_weekday_last& mwdl) noexcept;
+constexpr year_month_weekday_last
+ operator/(int y, const month_weekday_last& mwdl) noexcept;
+constexpr year_month_weekday_last
+ operator/(const month_weekday_last& mwdl, const year& y) noexcept;
+constexpr year_month_weekday_last
+ operator/(const month_weekday_last& mwdl, int y) noexcept;
+
+// 26.9, class template hh_mm_ss
+template <class Duration>
+class hh_mm_ss
+{
+ bool is_neg; // exposition only
+ chrono::hours h; // exposition only
+ chrono::minutes m; // exposition only
+ chrono::seconds s; // exposition only
+ precision ss; // exposition only
+
+public:
+ static unsigned constexpr fractional_width = see below;
+ using precision = see below;
+
+ constexpr hh_mm_ss() noexcept : hh_mm_ss{Duration::zero()} {}
+ constexpr explicit hh_mm_ss(Duration d) noexcept;
+
+ constexpr bool is_negative() const noexcept;
+ constexpr chrono::hours hours() const noexcept;
+ constexpr chrono::minutes minutes() const noexcept;
+ constexpr chrono::seconds seconds() const noexcept;
+ constexpr precision subseconds() const noexcept;
+
+ constexpr explicit operator precision() const noexcept;
+ constexpr precision to_duration() const noexcept;
+};
+
+template<class charT, class traits, class Duration>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const hh_mm_ss<Duration>& hms); // C++20
+
+// 26.10, 12/24 hour functions
+constexpr bool is_am(hours const& h) noexcept;
+constexpr bool is_pm(hours const& h) noexcept;
+constexpr hours make12(const hours& h) noexcept;
+constexpr hours make24(const hours& h, bool is_pm) noexcept;
+
+// [time.zone.db], time zone database
+struct tzdb { // C++20
+ string version;
+ vector<time_zone> zones;
+ vector<time_zone_link> links;
+ vector<leap_second> leap_seconds;
+
+ const time_zone* locate_zone(string_view tz_name) const;
+ const time_zone* current_zone() const;
+};
+
+class tzdb_list { // C++20
+public:
+ tzdb_list(const tzdb_list&) = delete;
+ tzdb_list& operator=(const tzdb_list&) = delete;
+
+ // unspecified additional constructors
+
+ class const_iterator;
+
+ const tzdb& front() const noexcept;
+
+ const_iterator erase_after(const_iterator p);
+
+ const_iterator begin() const noexcept;
+ const_iterator end() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+};
+
+// [time.zone.db.access], time zone database access
+const tzdb& get_tzdb(); // C++20
+tzdb_list& get_tzdb_list(); // C++20
+const time_zone* locate_zone(string_view tz_name); // C++20
+const time_zone* current_zone() // C++20
+
+// [time.zone.db.remote], remote time zone database support
+const tzdb& reload_tzdb(); // C++20
+string remote_version(); // C++20
+
+// [time.zone.exception], exception classes
+class nonexistent_local_time; // C++20
+class ambiguous_local_time; // C++20
+
+// [time.zone.info], information classes
+struct sys_info { // C++20
+ sys_seconds begin;
+ sys_seconds end;
+ seconds offset;
+ minutes save;
+ string abbrev;
+};
+
+template<class charT, class traits> // C++20
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const sys_info& si);
+
+struct local_info { // C++20
+ static constexpr int unique = 0;
+ static constexpr int nonexistent = 1;
+ static constexpr int ambiguous = 2;
+
+ int result;
+ sys_info first;
+ sys_info second;
+};
+
+template<class charT, class traits> // C++20
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const local_info& li);
+
+// 25.10.5, class time_zone // C++20
+enum class choose {earliest, latest};
+class time_zone {
+ time_zone(time_zone&&) = default;
+ time_zone& operator=(time_zone&&) = default;
+
+ // unspecified additional constructors
+
+ string_view name() const noexcept;
+
+ template<class Duration>
+ sys_info get_info(const sys_time<Duration>& st) const;
+
+ template<class Duration>
+ local_info get_info(const local_time<Duration>& tp) const;
+
+ template<class Duration>
+ sys_time<common_type_t<Duration, seconds>>
+ to_sys(const local_time<Duration>& tp) const;
+
+ template<class Duration>
+ sys_time<common_type_t<Duration, seconds>>
+ to_sys(const local_time<Duration>& tp, choose z) const;
+
+ template<class Duration>
+ local_time<common_type_t<Duration, seconds>>
+ to_local(const sys_time<Duration>& tp) const;
+};
+bool operator==(const time_zone& x, const time_zone& y) noexcept; // C++20
+strong_ordering operator<=>(const time_zone& x, const time_zone& y) noexcept; // C++20
+
+// [time.zone.zonedtraits], class template zoned_traits
+template<class T> struct zoned_traits; // C++20
+
+// [time.zone.zonedtime], class template zoned_time
+template<class Duration, class TimeZonePtr = const time_zone*> // C++20
+class zoned_time;
+
+using zoned_seconds = zoned_time<seconds>; // C++20
+
+template<class Duration1, class Duration2, class TimeZonePtr> // C++20
+ bool operator==(const zoned_time<Duration1, TimeZonePtr>& x,
+ const zoned_time<Duration2, TimeZonePtr>& y);
+
+template<class charT, class traits, class Duration, class TimeZonePtr> // C++20
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const zoned_time<Duration, TimeZonePtr>& t);
+
+// [time.zone.leap], leap second support
+class leap_second { // C++20
+public:
+ leap_second(const leap_second&) = default;
+ leap_second& operator=(const leap_second&) = default;
+
+ // unspecified additional constructors
+
+ constexpr sys_seconds date() const noexcept;
+ constexpr seconds value() const noexcept;
+};
+
+constexpr bool operator==(const leap_second& x, const leap_second& y); // C++20
+constexpr strong_ordering operator<=>(const leap_second& x, const leap_second& y);
+
+template<class Duration> // C++20
+ constexpr bool operator==(const leap_second& x, const sys_time<Duration>& y);
+template<class Duration> // C++20
+ constexpr bool operator< (const leap_second& x, const sys_time<Duration>& y);
+template<class Duration> // C++20
+ constexpr bool operator< (const sys_time<Duration>& x, const leap_second& y);
+template<class Duration> // C++20
+ constexpr bool operator> (const leap_second& x, const sys_time<Duration>& y);
+template<class Duration> // C++20
+ constexpr bool operator> (const sys_time<Duration>& x, const leap_second& y);
+template<class Duration> // C++20
+ constexpr bool operator<=(const leap_second& x, const sys_time<Duration>& y);
+template<class Duration> // C++20
+ constexpr bool operator<=(const sys_time<Duration>& x, const leap_second& y);
+template<class Duration> // C++20
+ constexpr bool operator>=(const leap_second& x, const sys_time<Duration>& y);
+template<class Duration> // C++20
+ constexpr bool operator>=(const sys_time<Duration>& x, const leap_second& y);
+template<class Duration> // C++20
+ requires three_way_comparable_with<sys_seconds, sys_time<Duration>>
+ constexpr auto operator<=>(const leap_second& x, const sys_time<Duration>& y);
+
+// [time.zone.link], class time_zone_link
+class time_zone_link { // C++20
+public:
+ time_zone_link(time_zone_link&&) = default;
+ time_zone_link& operator=(time_zone_link&&) = default;
+
+ // unspecified additional constructors
+
+ string_view name() const noexcept;
+ string_view target() const noexcept;
+};
+
+bool operator==(const time_zone_link& x, const time_zone_link& y); // C++20
+strong_ordering operator<=>(const time_zone_link& x, const time_zone_link& y); // C++20
+
+} // chrono
+
+namespace std {
+ template<class Duration, class charT>
+ struct formatter<chrono::sys_time<Duration>, charT>; // C++20
+ template<class Duration, class charT>
+ struct formatter<chrono::filetime<Duration>, charT>; // C++20
+ template<class Duration, class charT>
+ struct formatter<chrono::local_time<Duration>, charT>; // C++20
+ template<class Rep, class Period, class charT>
+ struct formatter<chrono::duration<Rep, Period>, charT>; // C++20
+ template<class charT> struct formatter<chrono::day, charT>; // C++20
+ template<class charT> struct formatter<chrono::month, charT>; // C++20
+ template<class charT> struct formatter<chrono::year, charT>; // C++20
+ template<class charT> struct formatter<chrono::weekday, charT>; // C++20
+ template<class charT> struct formatter<chrono::weekday_indexed, charT>; // C++20
+ template<class charT> struct formatter<chrono::weekday_last, charT>; // C++20
+ template<class charT> struct formatter<chrono::month_day, charT>; // C++20
+ template<class charT> struct formatter<chrono::month_day_last, charT>; // C++20
+ template<class charT> struct formatter<chrono::month_weekday, charT>; // C++20
+ template<class charT> struct formatter<chrono::month_weekday_last, charT>; // C++20
+ template<class charT> struct formatter<chrono::year_month, charT>; // C++20
+ template<class charT> struct formatter<chrono::year_month_day, charT>; // C++20
+ template<class charT> struct formatter<chrono::year_month_day_last, charT>; // C++20
+ template<class charT> struct formatter<chrono::year_month_weekday, charT>; // C++20
+ template<class charT> struct formatter<chrono::year_month_weekday_last, charT>; // C++20
+ template<class Rep, class Period, class charT>
+ struct formatter<chrono::hh_mm_ss<duration<Rep, Period>>, charT>; // C++20
+ template<class charT> struct formatter<chrono::sys_info, charT>; // C++20
+ template<class charT> struct formatter<chrono::local_info, charT>; // C++20
+ template<class Duration, class TimeZonePtr, class charT> // C++20
+ struct formatter<chrono::zoned_time<Duration, TimeZonePtr>, charT>;
+} // namespace std
+
+namespace chrono {
+// calendrical constants
+inline constexpr last_spec last{}; // C++20
+inline constexpr chrono::weekday Sunday{0}; // C++20
+inline constexpr chrono::weekday Monday{1}; // C++20
+inline constexpr chrono::weekday Tuesday{2}; // C++20
+inline constexpr chrono::weekday Wednesday{3}; // C++20
+inline constexpr chrono::weekday Thursday{4}; // C++20
+inline constexpr chrono::weekday Friday{5}; // C++20
+inline constexpr chrono::weekday Saturday{6}; // C++20
+
+inline constexpr chrono::month January{1}; // C++20
+inline constexpr chrono::month February{2}; // C++20
+inline constexpr chrono::month March{3}; // C++20
+inline constexpr chrono::month April{4}; // C++20
+inline constexpr chrono::month May{5}; // C++20
+inline constexpr chrono::month June{6}; // C++20
+inline constexpr chrono::month July{7}; // C++20
+inline constexpr chrono::month August{8}; // C++20
+inline constexpr chrono::month September{9}; // C++20
+inline constexpr chrono::month October{10}; // C++20
+inline constexpr chrono::month November{11}; // C++20
+inline constexpr chrono::month December{12}; // C++20
+} // chrono
+
+inline namespace literals {
+ inline namespace chrono_literals {
+constexpr chrono::hours operator ""h(unsigned long long); // C++14
+constexpr chrono::duration<unspecified , ratio<3600,1>> operator ""h(long double); // C++14
+constexpr chrono::minutes operator ""min(unsigned long long); // C++14
+constexpr chrono::duration<unspecified , ratio<60,1>> operator ""min(long double); // C++14
+constexpr chrono::seconds operator ""s(unsigned long long); // C++14
+constexpr chrono::duration<unspecified > operator ""s(long double); // C++14
+constexpr chrono::milliseconds operator ""ms(unsigned long long); // C++14
+constexpr chrono::duration<unspecified , milli> operator ""ms(long double); // C++14
+constexpr chrono::microseconds operator ""us(unsigned long long); // C++14
+constexpr chrono::duration<unspecified , micro> operator ""us(long double); // C++14
+constexpr chrono::nanoseconds operator ""ns(unsigned long long); // C++14
+constexpr chrono::duration<unspecified , nano> operator ""ns(long double); // C++14
+constexpr chrono::day operator ""d(unsigned long long d) noexcept; // C++20
+constexpr chrono::year operator ""y(unsigned long long y) noexcept; // C++20
+} // chrono_literals
+} // literals
+
+} // std
+*/
+
+// clang-format on
+
+#include <__config>
+
+#include <__chrono/duration.h>
+#include <__chrono/file_clock.h>
+#include <__chrono/high_resolution_clock.h>
+#include <__chrono/steady_clock.h>
+#include <__chrono/system_clock.h>
+#include <__chrono/time_point.h>
+
+#if _LIBCPP_STD_VER >= 20
+# include <__chrono/calendar.h>
+# include <__chrono/day.h>
+# include <__chrono/exception.h>
+# include <__chrono/hh_mm_ss.h>
+# include <__chrono/literals.h>
+# include <__chrono/local_info.h>
+# include <__chrono/month.h>
+# include <__chrono/month_weekday.h>
+# include <__chrono/monthday.h>
+# include <__chrono/sys_info.h>
+# include <__chrono/weekday.h>
+# include <__chrono/year.h>
+# include <__chrono/year_month.h>
+# include <__chrono/year_month_day.h>
+# include <__chrono/year_month_weekday.h>
+
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <__chrono/formatter.h>
+# include <__chrono/ostream.h>
+# include <__chrono/parser_std_format_spec.h>
+# include <__chrono/statically_widen.h>
+# endif
+
+# if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
+ !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <__chrono/leap_second.h>
+# include <__chrono/time_zone.h>
+# include <__chrono/time_zone_link.h>
+# include <__chrono/tzdb.h>
+# include <__chrono/tzdb_list.h>
+# include <__chrono/zoned_time.h>
+# endif
+
+#endif
+
+#include <version>
+
+// standard-mandated includes
+
+// [time.syn]
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <cstdint>
+# include <stdexcept>
+# include <string_view>
+# include <vector>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <bit>
+# include <concepts>
+# include <cstring>
+# include <forward_list>
+# include <string>
+# include <tuple>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER == 20
+# include <charconv>
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <locale>
+# include <ostream>
+# endif
+#endif
+
+#endif // _LIBCPP_CHRONO
diff --git a/libcxx/include/__cxx03/cinttypes b/libcxx/include/__cxx03/cinttypes
new file mode 100644
index 00000000000000..52663a4f35fad5
--- /dev/null
+++ b/libcxx/include/__cxx03/cinttypes
@@ -0,0 +1,270 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CINTTYPES
+#define _LIBCPP_CINTTYPES
+
+/*
+ cinttypes synopsis
+
+This entire header is C99 / C++0X
+
+#include <cstdint> // <cinttypes> includes <cstdint>
+
+Macros:
+
+ PRId8
+ PRId16
+ PRId32
+ PRId64
+
+ PRIdLEAST8
+ PRIdLEAST16
+ PRIdLEAST32
+ PRIdLEAST64
+
+ PRIdFAST8
+ PRIdFAST16
+ PRIdFAST32
+ PRIdFAST64
+
+ PRIdMAX
+ PRIdPTR
+
+ PRIi8
+ PRIi16
+ PRIi32
+ PRIi64
+
+ PRIiLEAST8
+ PRIiLEAST16
+ PRIiLEAST32
+ PRIiLEAST64
+
+ PRIiFAST8
+ PRIiFAST16
+ PRIiFAST32
+ PRIiFAST64
+
+ PRIiMAX
+ PRIiPTR
+
+ PRIo8
+ PRIo16
+ PRIo32
+ PRIo64
+
+ PRIoLEAST8
+ PRIoLEAST16
+ PRIoLEAST32
+ PRIoLEAST64
+
+ PRIoFAST8
+ PRIoFAST16
+ PRIoFAST32
+ PRIoFAST64
+
+ PRIoMAX
+ PRIoPTR
+
+ PRIu8
+ PRIu16
+ PRIu32
+ PRIu64
+
+ PRIuLEAST8
+ PRIuLEAST16
+ PRIuLEAST32
+ PRIuLEAST64
+
+ PRIuFAST8
+ PRIuFAST16
+ PRIuFAST32
+ PRIuFAST64
+
+ PRIuMAX
+ PRIuPTR
+
+ PRIx8
+ PRIx16
+ PRIx32
+ PRIx64
+
+ PRIxLEAST8
+ PRIxLEAST16
+ PRIxLEAST32
+ PRIxLEAST64
+
+ PRIxFAST8
+ PRIxFAST16
+ PRIxFAST32
+ PRIxFAST64
+
+ PRIxMAX
+ PRIxPTR
+
+ PRIX8
+ PRIX16
+ PRIX32
+ PRIX64
+
+ PRIXLEAST8
+ PRIXLEAST16
+ PRIXLEAST32
+ PRIXLEAST64
+
+ PRIXFAST8
+ PRIXFAST16
+ PRIXFAST32
+ PRIXFAST64
+
+ PRIXMAX
+ PRIXPTR
+
+ SCNd8
+ SCNd16
+ SCNd32
+ SCNd64
+
+ SCNdLEAST8
+ SCNdLEAST16
+ SCNdLEAST32
+ SCNdLEAST64
+
+ SCNdFAST8
+ SCNdFAST16
+ SCNdFAST32
+ SCNdFAST64
+
+ SCNdMAX
+ SCNdPTR
+
+ SCNi8
+ SCNi16
+ SCNi32
+ SCNi64
+
+ SCNiLEAST8
+ SCNiLEAST16
+ SCNiLEAST32
+ SCNiLEAST64
+
+ SCNiFAST8
+ SCNiFAST16
+ SCNiFAST32
+ SCNiFAST64
+
+ SCNiMAX
+ SCNiPTR
+
+ SCNo8
+ SCNo16
+ SCNo32
+ SCNo64
+
+ SCNoLEAST8
+ SCNoLEAST16
+ SCNoLEAST32
+ SCNoLEAST64
+
+ SCNoFAST8
+ SCNoFAST16
+ SCNoFAST32
+ SCNoFAST64
+
+ SCNoMAX
+ SCNoPTR
+
+ SCNu8
+ SCNu16
+ SCNu32
+ SCNu64
+
+ SCNuLEAST8
+ SCNuLEAST16
+ SCNuLEAST32
+ SCNuLEAST64
+
+ SCNuFAST8
+ SCNuFAST16
+ SCNuFAST32
+ SCNuFAST64
+
+ SCNuMAX
+ SCNuPTR
+
+ SCNx8
+ SCNx16
+ SCNx32
+ SCNx64
+
+ SCNxLEAST8
+ SCNxLEAST16
+ SCNxLEAST32
+ SCNxLEAST64
+
+ SCNxFAST8
+ SCNxFAST16
+ SCNxFAST32
+ SCNxFAST64
+
+ SCNxMAX
+ SCNxPTR
+
+namespace std
+{
+
+Types:
+
+ imaxdiv_t
+
+intmax_t imaxabs(intmax_t j);
+imaxdiv_t imaxdiv(intmax_t numer, intmax_t denom);
+intmax_t strtoimax(const char* restrict nptr, char** restrict endptr, int base);
+uintmax_t strtoumax(const char* restrict nptr, char** restrict endptr, int base);
+intmax_t wcstoimax(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base);
+uintmax_t wcstoumax(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base);
+
+} // std
+*/
+
+#include <__config>
+
+// standard-mandated includes
+
+// [cinttypes.syn]
+#include <cstdint>
+
+#include <inttypes.h>
+
+#ifndef _LIBCPP_INTTYPES_H
+# error <cinttypes> tried including <inttypes.h> but didn't find libc++'s <inttypes.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::imaxdiv_t _LIBCPP_USING_IF_EXISTS;
+using ::imaxabs _LIBCPP_USING_IF_EXISTS;
+using ::imaxdiv _LIBCPP_USING_IF_EXISTS;
+using ::strtoimax _LIBCPP_USING_IF_EXISTS;
+using ::strtoumax _LIBCPP_USING_IF_EXISTS;
+using ::wcstoimax _LIBCPP_USING_IF_EXISTS;
+using ::wcstoumax _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CINTTYPES
diff --git a/libcxx/include/__cxx03/ciso646 b/libcxx/include/__cxx03/ciso646
new file mode 100644
index 00000000000000..1d859f08fac572
--- /dev/null
+++ b/libcxx/include/__cxx03/ciso646
@@ -0,0 +1,24 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CISO646
+#define _LIBCPP_CISO646
+
+/*
+ ciso646 synopsis
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#endif // _LIBCPP_CISO646
diff --git a/libcxx/include/__cxx03/climits b/libcxx/include/__cxx03/climits
new file mode 100644
index 00000000000000..bcd8b4a56a073c
--- /dev/null
+++ b/libcxx/include/__cxx03/climits
@@ -0,0 +1,48 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CLIMITS
+#define _LIBCPP_CLIMITS
+
+/*
+ climits synopsis
+
+Macros:
+
+ CHAR_BIT
+ SCHAR_MIN
+ SCHAR_MAX
+ UCHAR_MAX
+ CHAR_MIN
+ CHAR_MAX
+ MB_LEN_MAX
+ SHRT_MIN
+ SHRT_MAX
+ USHRT_MAX
+ INT_MIN
+ INT_MAX
+ UINT_MAX
+ LONG_MIN
+ LONG_MAX
+ ULONG_MAX
+ LLONG_MIN // C99
+ LLONG_MAX // C99
+ ULLONG_MAX // C99
+
+*/
+
+#include <__config>
+
+#include <limits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#endif // _LIBCPP_CLIMITS
diff --git a/libcxx/include/__cxx03/clocale b/libcxx/include/__cxx03/clocale
new file mode 100644
index 00000000000000..c689a64be288a3
--- /dev/null
+++ b/libcxx/include/__cxx03/clocale
@@ -0,0 +1,61 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CLOCALE
+#define _LIBCPP_CLOCALE
+
+/*
+ clocale synopsis
+
+Macros:
+
+ LC_ALL
+ LC_COLLATE
+ LC_CTYPE
+ LC_MONETARY
+ LC_NUMERIC
+ LC_TIME
+ NULL
+
+namespace std
+{
+
+struct lconv;
+char* setlocale(int category, const char* locale);
+lconv* localeconv();
+
+} // std
+
+*/
+
+#include <__config>
+
+#include <locale.h>
+
+#ifndef _LIBCPP_LOCALE_H
+# error <clocale> tried including <locale.h> but didn't find libc++'s <locale.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::lconv _LIBCPP_USING_IF_EXISTS;
+using ::setlocale _LIBCPP_USING_IF_EXISTS;
+using ::localeconv _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CLOCALE
diff --git a/libcxx/include/__cxx03/cmath b/libcxx/include/__cxx03/cmath
new file mode 100644
index 00000000000000..6480c4678ce33d
--- /dev/null
+++ b/libcxx/include/__cxx03/cmath
@@ -0,0 +1,646 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CMATH
+#define _LIBCPP_CMATH
+
+/*
+ cmath synopsis
+
+Macros:
+
+ HUGE_VAL
+ HUGE_VALF // C99
+ HUGE_VALL // C99
+ INFINITY // C99
+ NAN // C99
+ FP_INFINITE // C99
+ FP_NAN // C99
+ FP_NORMAL // C99
+ FP_SUBNORMAL // C99
+ FP_ZERO // C99
+ FP_FAST_FMA // C99
+ FP_FAST_FMAF // C99
+ FP_FAST_FMAL // C99
+ FP_ILOGB0 // C99
+ FP_ILOGBNAN // C99
+ MATH_ERRNO // C99
+ MATH_ERREXCEPT // C99
+ math_errhandling // C99
+
+namespace std
+{
+
+Types:
+
+ float_t // C99
+ double_t // C99
+
+// C90
+
+floating_point abs(floating_point x);
+
+floating_point acos (arithmetic x);
+float acosf(float x);
+long double acosl(long double x);
+
+floating_point asin (arithmetic x);
+float asinf(float x);
+long double asinl(long double x);
+
+floating_point atan (arithmetic x);
+float atanf(float x);
+long double atanl(long double x);
+
+floating_point atan2 (arithmetic y, arithmetic x);
+float atan2f(float y, float x);
+long double atan2l(long double y, long double x);
+
+floating_point ceil (arithmetic x);
+float ceilf(float x);
+long double ceill(long double x);
+
+floating_point cos (arithmetic x);
+float cosf(float x);
+long double cosl(long double x);
+
+floating_point cosh (arithmetic x);
+float coshf(float x);
+long double coshl(long double x);
+
+floating_point exp (arithmetic x);
+float expf(float x);
+long double expl(long double x);
+
+floating_point fabs (arithmetic x);
+float fabsf(float x);
+long double fabsl(long double x);
+
+floating_point floor (arithmetic x);
+float floorf(float x);
+long double floorl(long double x);
+
+floating_point fmod (arithmetic x, arithmetic y);
+float fmodf(float x, float y);
+long double fmodl(long double x, long double y);
+
+floating_point frexp (arithmetic value, int* exp);
+float frexpf(float value, int* exp);
+long double frexpl(long double value, int* exp);
+
+floating_point ldexp (arithmetic value, int exp);
+float ldexpf(float value, int exp);
+long double ldexpl(long double value, int exp);
+
+floating_point log (arithmetic x);
+float logf(float x);
+long double logl(long double x);
+
+floating_point log10 (arithmetic x);
+float log10f(float x);
+long double log10l(long double x);
+
+floating_point modf (floating_point value, floating_point* iptr);
+float modff(float value, float* iptr);
+long double modfl(long double value, long double* iptr);
+
+floating_point pow (arithmetic x, arithmetic y);
+float powf(float x, float y);
+long double powl(long double x, long double y);
+
+floating_point sin (arithmetic x);
+float sinf(float x);
+long double sinl(long double x);
+
+floating_point sinh (arithmetic x);
+float sinhf(float x);
+long double sinhl(long double x);
+
+floating_point sqrt (arithmetic x);
+float sqrtf(float x);
+long double sqrtl(long double x);
+
+floating_point tan (arithmetic x);
+float tanf(float x);
+long double tanl(long double x);
+
+floating_point tanh (arithmetic x);
+float tanhf(float x);
+long double tanhl(long double x);
+
+// C99
+
+bool signbit(arithmetic x);
+
+int fpclassify(arithmetic x);
+
+bool isfinite(arithmetic x);
+bool isinf(arithmetic x);
+bool isnan(arithmetic x);
+bool isnormal(arithmetic x);
+
+bool isgreater(arithmetic x, arithmetic y);
+bool isgreaterequal(arithmetic x, arithmetic y);
+bool isless(arithmetic x, arithmetic y);
+bool islessequal(arithmetic x, arithmetic y);
+bool islessgreater(arithmetic x, arithmetic y);
+bool isunordered(arithmetic x, arithmetic y);
+
+floating_point acosh (arithmetic x);
+float acoshf(float x);
+long double acoshl(long double x);
+
+floating_point asinh (arithmetic x);
+float asinhf(float x);
+long double asinhl(long double x);
+
+floating_point atanh (arithmetic x);
+float atanhf(float x);
+long double atanhl(long double x);
+
+floating_point cbrt (arithmetic x);
+float cbrtf(float x);
+long double cbrtl(long double x);
+
+floating_point copysign (arithmetic x, arithmetic y);
+float copysignf(float x, float y);
+long double copysignl(long double x, long double y);
+
+floating_point erf (arithmetic x);
+float erff(float x);
+long double erfl(long double x);
+
+floating_point erfc (arithmetic x);
+float erfcf(float x);
+long double erfcl(long double x);
+
+floating_point exp2 (arithmetic x);
+float exp2f(float x);
+long double exp2l(long double x);
+
+floating_point expm1 (arithmetic x);
+float expm1f(float x);
+long double expm1l(long double x);
+
+floating_point fdim (arithmetic x, arithmetic y);
+float fdimf(float x, float y);
+long double fdiml(long double x, long double y);
+
+floating_point fma (arithmetic x, arithmetic y, arithmetic z);
+float fmaf(float x, float y, float z);
+long double fmal(long double x, long double y, long double z);
+
+floating_point fmax (arithmetic x, arithmetic y);
+float fmaxf(float x, float y);
+long double fmaxl(long double x, long double y);
+
+floating_point fmin (arithmetic x, arithmetic y);
+float fminf(float x, float y);
+long double fminl(long double x, long double y);
+
+double hermite(unsigned n, double x); // C++17
+float hermite(unsigned n, float x); // C++17
+long double hermite(unsigned n, long double x); // C++17
+float hermitef(unsigned n, float x); // C++17
+long double hermitel(unsigned n, long double x); // C++17
+template <class Integer>
+double hermite(unsigned n, Integer x); // C++17
+
+floating_point hypot (arithmetic x, arithmetic y);
+float hypotf(float x, float y);
+long double hypotl(long double x, long double y);
+
+double hypot(double x, double y, double z); // C++17
+float hypot(float x, float y, float z); // C++17
+long double hypot(long double x, long double y, long double z); // C++17
+
+int ilogb (arithmetic x);
+int ilogbf(float x);
+int ilogbl(long double x);
+
+floating_point lgamma (arithmetic x);
+float lgammaf(float x);
+long double lgammal(long double x);
+
+long long llrint (arithmetic x);
+long long llrintf(float x);
+long long llrintl(long double x);
+
+long long llround (arithmetic x);
+long long llroundf(float x);
+long long llroundl(long double x);
+
+floating_point log1p (arithmetic x);
+float log1pf(float x);
+long double log1pl(long double x);
+
+floating_point log2 (arithmetic x);
+float log2f(float x);
+long double log2l(long double x);
+
+floating_point logb (arithmetic x);
+float logbf(float x);
+long double logbl(long double x);
+
+long lrint (arithmetic x);
+long lrintf(float x);
+long lrintl(long double x);
+
+long lround (arithmetic x);
+long lroundf(float x);
+long lroundl(long double x);
+
+double nan (const char* str);
+float nanf(const char* str);
+long double nanl(const char* str);
+
+floating_point nearbyint (arithmetic x);
+float nearbyintf(float x);
+long double nearbyintl(long double x);
+
+floating_point nextafter (arithmetic x, arithmetic y);
+float nextafterf(float x, float y);
+long double nextafterl(long double x, long double y);
+
+floating_point nexttoward (arithmetic x, long double y);
+float nexttowardf(float x, long double y);
+long double nexttowardl(long double x, long double y);
+
+floating_point remainder (arithmetic x, arithmetic y);
+float remainderf(float x, float y);
+long double remainderl(long double x, long double y);
+
+floating_point remquo (arithmetic x, arithmetic y, int* pquo);
+float remquof(float x, float y, int* pquo);
+long double remquol(long double x, long double y, int* pquo);
+
+floating_point rint (arithmetic x);
+float rintf(float x);
+long double rintl(long double x);
+
+floating_point round (arithmetic x);
+float roundf(float x);
+long double roundl(long double x);
+
+floating_point scalbln (arithmetic x, long ex);
+float scalblnf(float x, long ex);
+long double scalblnl(long double x, long ex);
+
+floating_point scalbn (arithmetic x, int ex);
+float scalbnf(float x, int ex);
+long double scalbnl(long double x, int ex);
+
+floating_point tgamma (arithmetic x);
+float tgammaf(float x);
+long double tgammal(long double x);
+
+floating_point trunc (arithmetic x);
+float truncf(float x);
+long double truncl(long double x);
+
+constexpr float lerp(float a, float b, float t) noexcept; // C++20
+constexpr double lerp(double a, double b, double t) noexcept; // C++20
+constexpr long double lerp(long double a, long double b, long double t) noexcept; // C++20
+
+} // std
+
+*/
+
+#include <__config>
+#include <__math/hypot.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/promote.h>
+#include <__type_traits/remove_cv.h>
+#include <limits>
+#include <version>
+
+#include <__math/special_functions.h>
+#include <math.h>
+
+#ifndef _LIBCPP_MATH_H
+# error <cmath> tried including <math.h> but didn't find libc++'s <math.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::signbit _LIBCPP_USING_IF_EXISTS;
+using ::fpclassify _LIBCPP_USING_IF_EXISTS;
+using ::isfinite _LIBCPP_USING_IF_EXISTS;
+using ::isinf _LIBCPP_USING_IF_EXISTS;
+using ::isnan _LIBCPP_USING_IF_EXISTS;
+using ::isnormal _LIBCPP_USING_IF_EXISTS;
+using ::isgreater _LIBCPP_USING_IF_EXISTS;
+using ::isgreaterequal _LIBCPP_USING_IF_EXISTS;
+using ::isless _LIBCPP_USING_IF_EXISTS;
+using ::islessequal _LIBCPP_USING_IF_EXISTS;
+using ::islessgreater _LIBCPP_USING_IF_EXISTS;
+using ::isunordered _LIBCPP_USING_IF_EXISTS;
+using ::isunordered _LIBCPP_USING_IF_EXISTS;
+
+using ::float_t _LIBCPP_USING_IF_EXISTS;
+using ::double_t _LIBCPP_USING_IF_EXISTS;
+
+using ::abs _LIBCPP_USING_IF_EXISTS;
+
+using ::acos _LIBCPP_USING_IF_EXISTS;
+using ::acosf _LIBCPP_USING_IF_EXISTS;
+using ::asin _LIBCPP_USING_IF_EXISTS;
+using ::asinf _LIBCPP_USING_IF_EXISTS;
+using ::atan _LIBCPP_USING_IF_EXISTS;
+using ::atanf _LIBCPP_USING_IF_EXISTS;
+using ::atan2 _LIBCPP_USING_IF_EXISTS;
+using ::atan2f _LIBCPP_USING_IF_EXISTS;
+using ::ceil _LIBCPP_USING_IF_EXISTS;
+using ::ceilf _LIBCPP_USING_IF_EXISTS;
+using ::cos _LIBCPP_USING_IF_EXISTS;
+using ::cosf _LIBCPP_USING_IF_EXISTS;
+using ::cosh _LIBCPP_USING_IF_EXISTS;
+using ::coshf _LIBCPP_USING_IF_EXISTS;
+
+using ::exp _LIBCPP_USING_IF_EXISTS;
+using ::expf _LIBCPP_USING_IF_EXISTS;
+
+using ::fabs _LIBCPP_USING_IF_EXISTS;
+using ::fabsf _LIBCPP_USING_IF_EXISTS;
+using ::floor _LIBCPP_USING_IF_EXISTS;
+using ::floorf _LIBCPP_USING_IF_EXISTS;
+
+using ::fmod _LIBCPP_USING_IF_EXISTS;
+using ::fmodf _LIBCPP_USING_IF_EXISTS;
+
+using ::frexp _LIBCPP_USING_IF_EXISTS;
+using ::frexpf _LIBCPP_USING_IF_EXISTS;
+using ::ldexp _LIBCPP_USING_IF_EXISTS;
+using ::ldexpf _LIBCPP_USING_IF_EXISTS;
+
+using ::log _LIBCPP_USING_IF_EXISTS;
+using ::logf _LIBCPP_USING_IF_EXISTS;
+
+using ::log10 _LIBCPP_USING_IF_EXISTS;
+using ::log10f _LIBCPP_USING_IF_EXISTS;
+using ::modf _LIBCPP_USING_IF_EXISTS;
+using ::modff _LIBCPP_USING_IF_EXISTS;
+
+using ::pow _LIBCPP_USING_IF_EXISTS;
+using ::powf _LIBCPP_USING_IF_EXISTS;
+
+using ::sin _LIBCPP_USING_IF_EXISTS;
+using ::sinf _LIBCPP_USING_IF_EXISTS;
+using ::sinh _LIBCPP_USING_IF_EXISTS;
+using ::sinhf _LIBCPP_USING_IF_EXISTS;
+
+using ::sqrt _LIBCPP_USING_IF_EXISTS;
+using ::sqrtf _LIBCPP_USING_IF_EXISTS;
+using ::tan _LIBCPP_USING_IF_EXISTS;
+using ::tanf _LIBCPP_USING_IF_EXISTS;
+
+using ::tanh _LIBCPP_USING_IF_EXISTS;
+using ::tanhf _LIBCPP_USING_IF_EXISTS;
+
+using ::acosh _LIBCPP_USING_IF_EXISTS;
+using ::acoshf _LIBCPP_USING_IF_EXISTS;
+using ::asinh _LIBCPP_USING_IF_EXISTS;
+using ::asinhf _LIBCPP_USING_IF_EXISTS;
+using ::atanh _LIBCPP_USING_IF_EXISTS;
+using ::atanhf _LIBCPP_USING_IF_EXISTS;
+using ::cbrt _LIBCPP_USING_IF_EXISTS;
+using ::cbrtf _LIBCPP_USING_IF_EXISTS;
+
+using ::copysign _LIBCPP_USING_IF_EXISTS;
+using ::copysignf _LIBCPP_USING_IF_EXISTS;
+
+using ::erf _LIBCPP_USING_IF_EXISTS;
+using ::erff _LIBCPP_USING_IF_EXISTS;
+using ::erfc _LIBCPP_USING_IF_EXISTS;
+using ::erfcf _LIBCPP_USING_IF_EXISTS;
+using ::exp2 _LIBCPP_USING_IF_EXISTS;
+using ::exp2f _LIBCPP_USING_IF_EXISTS;
+using ::expm1 _LIBCPP_USING_IF_EXISTS;
+using ::expm1f _LIBCPP_USING_IF_EXISTS;
+using ::fdim _LIBCPP_USING_IF_EXISTS;
+using ::fdimf _LIBCPP_USING_IF_EXISTS;
+using ::fmaf _LIBCPP_USING_IF_EXISTS;
+using ::fma _LIBCPP_USING_IF_EXISTS;
+using ::fmax _LIBCPP_USING_IF_EXISTS;
+using ::fmaxf _LIBCPP_USING_IF_EXISTS;
+using ::fmin _LIBCPP_USING_IF_EXISTS;
+using ::fminf _LIBCPP_USING_IF_EXISTS;
+using ::hypot _LIBCPP_USING_IF_EXISTS;
+using ::hypotf _LIBCPP_USING_IF_EXISTS;
+using ::ilogb _LIBCPP_USING_IF_EXISTS;
+using ::ilogbf _LIBCPP_USING_IF_EXISTS;
+using ::lgamma _LIBCPP_USING_IF_EXISTS;
+using ::lgammaf _LIBCPP_USING_IF_EXISTS;
+using ::llrint _LIBCPP_USING_IF_EXISTS;
+using ::llrintf _LIBCPP_USING_IF_EXISTS;
+using ::llround _LIBCPP_USING_IF_EXISTS;
+using ::llroundf _LIBCPP_USING_IF_EXISTS;
+using ::log1p _LIBCPP_USING_IF_EXISTS;
+using ::log1pf _LIBCPP_USING_IF_EXISTS;
+using ::log2 _LIBCPP_USING_IF_EXISTS;
+using ::log2f _LIBCPP_USING_IF_EXISTS;
+using ::logb _LIBCPP_USING_IF_EXISTS;
+using ::logbf _LIBCPP_USING_IF_EXISTS;
+using ::lrint _LIBCPP_USING_IF_EXISTS;
+using ::lrintf _LIBCPP_USING_IF_EXISTS;
+using ::lround _LIBCPP_USING_IF_EXISTS;
+using ::lroundf _LIBCPP_USING_IF_EXISTS;
+
+using ::nan _LIBCPP_USING_IF_EXISTS;
+using ::nanf _LIBCPP_USING_IF_EXISTS;
+
+using ::nearbyint _LIBCPP_USING_IF_EXISTS;
+using ::nearbyintf _LIBCPP_USING_IF_EXISTS;
+using ::nextafter _LIBCPP_USING_IF_EXISTS;
+using ::nextafterf _LIBCPP_USING_IF_EXISTS;
+using ::nexttoward _LIBCPP_USING_IF_EXISTS;
+using ::nexttowardf _LIBCPP_USING_IF_EXISTS;
+using ::remainder _LIBCPP_USING_IF_EXISTS;
+using ::remainderf _LIBCPP_USING_IF_EXISTS;
+using ::remquo _LIBCPP_USING_IF_EXISTS;
+using ::remquof _LIBCPP_USING_IF_EXISTS;
+using ::rint _LIBCPP_USING_IF_EXISTS;
+using ::rintf _LIBCPP_USING_IF_EXISTS;
+using ::round _LIBCPP_USING_IF_EXISTS;
+using ::roundf _LIBCPP_USING_IF_EXISTS;
+using ::scalbln _LIBCPP_USING_IF_EXISTS;
+using ::scalblnf _LIBCPP_USING_IF_EXISTS;
+using ::scalbn _LIBCPP_USING_IF_EXISTS;
+using ::scalbnf _LIBCPP_USING_IF_EXISTS;
+using ::tgamma _LIBCPP_USING_IF_EXISTS;
+using ::tgammaf _LIBCPP_USING_IF_EXISTS;
+using ::trunc _LIBCPP_USING_IF_EXISTS;
+using ::truncf _LIBCPP_USING_IF_EXISTS;
+
+using ::acosl _LIBCPP_USING_IF_EXISTS;
+using ::asinl _LIBCPP_USING_IF_EXISTS;
+using ::atanl _LIBCPP_USING_IF_EXISTS;
+using ::atan2l _LIBCPP_USING_IF_EXISTS;
+using ::ceill _LIBCPP_USING_IF_EXISTS;
+using ::cosl _LIBCPP_USING_IF_EXISTS;
+using ::coshl _LIBCPP_USING_IF_EXISTS;
+using ::expl _LIBCPP_USING_IF_EXISTS;
+using ::fabsl _LIBCPP_USING_IF_EXISTS;
+using ::floorl _LIBCPP_USING_IF_EXISTS;
+using ::fmodl _LIBCPP_USING_IF_EXISTS;
+using ::frexpl _LIBCPP_USING_IF_EXISTS;
+using ::ldexpl _LIBCPP_USING_IF_EXISTS;
+using ::logl _LIBCPP_USING_IF_EXISTS;
+using ::log10l _LIBCPP_USING_IF_EXISTS;
+using ::modfl _LIBCPP_USING_IF_EXISTS;
+using ::powl _LIBCPP_USING_IF_EXISTS;
+using ::sinl _LIBCPP_USING_IF_EXISTS;
+using ::sinhl _LIBCPP_USING_IF_EXISTS;
+using ::sqrtl _LIBCPP_USING_IF_EXISTS;
+using ::tanl _LIBCPP_USING_IF_EXISTS;
+
+using ::tanhl _LIBCPP_USING_IF_EXISTS;
+using ::acoshl _LIBCPP_USING_IF_EXISTS;
+using ::asinhl _LIBCPP_USING_IF_EXISTS;
+using ::atanhl _LIBCPP_USING_IF_EXISTS;
+using ::cbrtl _LIBCPP_USING_IF_EXISTS;
+
+using ::copysignl _LIBCPP_USING_IF_EXISTS;
+
+using ::erfl _LIBCPP_USING_IF_EXISTS;
+using ::erfcl _LIBCPP_USING_IF_EXISTS;
+using ::exp2l _LIBCPP_USING_IF_EXISTS;
+using ::expm1l _LIBCPP_USING_IF_EXISTS;
+using ::fdiml _LIBCPP_USING_IF_EXISTS;
+using ::fmal _LIBCPP_USING_IF_EXISTS;
+using ::fmaxl _LIBCPP_USING_IF_EXISTS;
+using ::fminl _LIBCPP_USING_IF_EXISTS;
+using ::hypotl _LIBCPP_USING_IF_EXISTS;
+using ::ilogbl _LIBCPP_USING_IF_EXISTS;
+using ::lgammal _LIBCPP_USING_IF_EXISTS;
+using ::llrintl _LIBCPP_USING_IF_EXISTS;
+using ::llroundl _LIBCPP_USING_IF_EXISTS;
+using ::log1pl _LIBCPP_USING_IF_EXISTS;
+using ::log2l _LIBCPP_USING_IF_EXISTS;
+using ::logbl _LIBCPP_USING_IF_EXISTS;
+using ::lrintl _LIBCPP_USING_IF_EXISTS;
+using ::lroundl _LIBCPP_USING_IF_EXISTS;
+using ::nanl _LIBCPP_USING_IF_EXISTS;
+using ::nearbyintl _LIBCPP_USING_IF_EXISTS;
+using ::nextafterl _LIBCPP_USING_IF_EXISTS;
+using ::nexttowardl _LIBCPP_USING_IF_EXISTS;
+using ::remainderl _LIBCPP_USING_IF_EXISTS;
+using ::remquol _LIBCPP_USING_IF_EXISTS;
+using ::rintl _LIBCPP_USING_IF_EXISTS;
+using ::roundl _LIBCPP_USING_IF_EXISTS;
+using ::scalblnl _LIBCPP_USING_IF_EXISTS;
+using ::scalbnl _LIBCPP_USING_IF_EXISTS;
+using ::tgammal _LIBCPP_USING_IF_EXISTS;
+using ::truncl _LIBCPP_USING_IF_EXISTS;
+
+template <class _A1, __enable_if_t<is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool __constexpr_isnan(_A1 __lcpp_x) _NOEXCEPT {
+#if __has_builtin(__builtin_isnan)
+ return __builtin_isnan(__lcpp_x);
+#else
+ return isnan(__lcpp_x);
+#endif
+}
+
+template <class _A1, __enable_if_t<!is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool __constexpr_isnan(_A1 __lcpp_x) _NOEXCEPT {
+ return std::isnan(__lcpp_x);
+}
+
+template <class _A1, __enable_if_t<is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool __constexpr_isinf(_A1 __lcpp_x) _NOEXCEPT {
+#if __has_builtin(__builtin_isinf)
+ return __builtin_isinf(__lcpp_x);
+#else
+ return isinf(__lcpp_x);
+#endif
+}
+
+template <class _A1, __enable_if_t<!is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool __constexpr_isinf(_A1 __lcpp_x) _NOEXCEPT {
+ return std::isinf(__lcpp_x);
+}
+
+template <class _A1, __enable_if_t<is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool __constexpr_isfinite(_A1 __lcpp_x) _NOEXCEPT {
+#if __has_builtin(__builtin_isfinite)
+ return __builtin_isfinite(__lcpp_x);
+#else
+ return isfinite(__lcpp_x);
+#endif
+}
+
+template <class _A1, __enable_if_t<!is_floating_point<_A1>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool __constexpr_isfinite(_A1 __lcpp_x) _NOEXCEPT {
+ return __builtin_isfinite(__lcpp_x);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <typename _Fp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Fp __lerp(_Fp __a, _Fp __b, _Fp __t) noexcept {
+ if ((__a <= 0 && __b >= 0) || (__a >= 0 && __b <= 0))
+ return __t * __b + (1 - __t) * __a;
+
+ if (__t == 1)
+ return __b;
+ const _Fp __x = __a + __t * (__b - __a);
+ if ((__t > 1) == (__b > __a))
+ return __b < __x ? __x : __b;
+ else
+ return __x < __b ? __x : __b;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr float lerp(float __a, float __b, float __t) _NOEXCEPT {
+ return __lerp(__a, __b, __t);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr double lerp(double __a, double __b, double __t) _NOEXCEPT {
+ return __lerp(__a, __b, __t);
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr long double lerp(long double __a, long double __b, long double __t) _NOEXCEPT {
+ return __lerp(__a, __b, __t);
+}
+
+template <class _A1, class _A2, class _A3>
+inline _LIBCPP_HIDE_FROM_ABI constexpr
+ typename enable_if_t< is_arithmetic<_A1>::value && is_arithmetic<_A2>::value && is_arithmetic<_A3>::value,
+ __promote<_A1, _A2, _A3> >::type
+ lerp(_A1 __a, _A2 __b, _A3 __t) noexcept {
+ typedef typename __promote<_A1, _A2, _A3>::type __result_type;
+ static_assert(!(
+ _IsSame<_A1, __result_type>::value && _IsSame<_A2, __result_type>::value && _IsSame<_A3, __result_type>::value));
+ return std::__lerp((__result_type)__a, (__result_type)__b, (__result_type)__t);
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_CMATH
diff --git a/libcxx/include/__cxx03/codecvt b/libcxx/include/__cxx03/codecvt
new file mode 100644
index 00000000000000..65cd752d69460e
--- /dev/null
+++ b/libcxx/include/__cxx03/codecvt
@@ -0,0 +1,597 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CODECVT
+#define _LIBCPP_CODECVT
+
+/*
+ codecvt synopsis
+
+namespace std
+{
+
+enum codecvt_mode
+{
+ consume_header = 4,
+ generate_header = 2,
+ little_endian = 1
+};
+
+template <class Elem, unsigned long Maxcode = 0x10ffff,
+ codecvt_mode Mode = (codecvt_mode)0>
+class codecvt_utf8
+ : public codecvt<Elem, char, mbstate_t>
+{
+ explicit codecvt_utf8(size_t refs = 0);
+ ~codecvt_utf8();
+};
+
+template <class Elem, unsigned long Maxcode = 0x10ffff,
+ codecvt_mode Mode = (codecvt_mode)0>
+class codecvt_utf16
+ : public codecvt<Elem, char, mbstate_t>
+{
+ explicit codecvt_utf16(size_t refs = 0);
+ ~codecvt_utf16();
+};
+
+template <class Elem, unsigned long Maxcode = 0x10ffff,
+ codecvt_mode Mode = (codecvt_mode)0>
+class codecvt_utf8_utf16
+ : public codecvt<Elem, char, mbstate_t>
+{
+ explicit codecvt_utf8_utf16(size_t refs = 0);
+ ~codecvt_utf8_utf16();
+};
+
+} // std
+
+*/
+
+#include <__config>
+#include <__locale>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER < 26 || defined(_LIBCPP_BUILDING_LIBRARY) || defined(_LIBCPP_ENABLE_CXX26_REMOVED_CODECVT)
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+enum _LIBCPP_DEPRECATED_IN_CXX17 codecvt_mode { consume_header = 4, generate_header = 2, little_endian = 1 };
+
+// codecvt_utf8
+
+template <class _Elem>
+class __codecvt_utf8;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf8<wchar_t> : public codecvt<wchar_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ codecvt_mode __mode_;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ typedef wchar_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf8(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<wchar_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf8<char16_t> : public codecvt<char16_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ codecvt_mode __mode_;
+
+public:
+ typedef char16_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf8(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<char16_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf8<char32_t> : public codecvt<char32_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ codecvt_mode __mode_;
+
+public:
+ typedef char32_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf8(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<char32_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Elem, unsigned long _Maxcode = 0x10ffff, codecvt_mode _Mode = (codecvt_mode)0>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 codecvt_utf8 : public __codecvt_utf8<_Elem> {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt_utf8(size_t __refs = 0) : __codecvt_utf8<_Elem>(__refs, _Maxcode, _Mode) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~codecvt_utf8() {}
+};
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+// codecvt_utf16
+
+template <class _Elem, bool _LittleEndian>
+class __codecvt_utf16;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf16<wchar_t, false> : public codecvt<wchar_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ codecvt_mode __mode_;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ typedef wchar_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<wchar_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf16<wchar_t, true> : public codecvt<wchar_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ codecvt_mode __mode_;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ typedef wchar_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<wchar_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf16<char16_t, false> : public codecvt<char16_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ codecvt_mode __mode_;
+
+public:
+ typedef char16_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<char16_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf16<char16_t, true> : public codecvt<char16_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ codecvt_mode __mode_;
+
+public:
+ typedef char16_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<char16_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf16<char32_t, false> : public codecvt<char32_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ codecvt_mode __mode_;
+
+public:
+ typedef char32_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<char32_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf16<char32_t, true> : public codecvt<char32_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ codecvt_mode __mode_;
+
+public:
+ typedef char32_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<char32_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Elem, unsigned long _Maxcode = 0x10ffff, codecvt_mode _Mode = (codecvt_mode)0>
+class _LIBCPP_TEMPLATE_VIS
+_LIBCPP_DEPRECATED_IN_CXX17 codecvt_utf16 : public __codecvt_utf16<_Elem, _Mode & little_endian> {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt_utf16(size_t __refs = 0)
+ : __codecvt_utf16<_Elem, _Mode & little_endian>(__refs, _Maxcode, _Mode) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~codecvt_utf16() {}
+};
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+// codecvt_utf8_utf16
+
+template <class _Elem>
+class __codecvt_utf8_utf16;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf8_utf16<wchar_t> : public codecvt<wchar_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ codecvt_mode __mode_;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+public:
+ typedef wchar_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf8_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<wchar_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf8_utf16<char32_t> : public codecvt<char32_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ codecvt_mode __mode_;
+
+public:
+ typedef char32_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf8_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<char32_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI __codecvt_utf8_utf16<char16_t> : public codecvt<char16_t, char, mbstate_t> {
+ unsigned long __maxcode_;
+ codecvt_mode __mode_;
+
+public:
+ typedef char16_t intern_type;
+ typedef char extern_type;
+ typedef mbstate_t state_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __codecvt_utf8_utf16(size_t __refs, unsigned long __maxcode, codecvt_mode __mode)
+ : codecvt<char16_t, char, mbstate_t>(__refs), __maxcode_(__maxcode), __mode_(__mode) {}
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ result do_out(state_type& __st,
+ const intern_type* __frm,
+ const intern_type* __frm_end,
+ const intern_type*& __frm_nxt,
+ extern_type* __to,
+ extern_type* __to_end,
+ extern_type*& __to_nxt) const override;
+ result do_in(state_type& __st,
+ const extern_type* __frm,
+ const extern_type* __frm_end,
+ const extern_type*& __frm_nxt,
+ intern_type* __to,
+ intern_type* __to_end,
+ intern_type*& __to_nxt) const override;
+ result do_unshift(state_type& __st, extern_type* __to, extern_type* __to_end, extern_type*& __to_nxt) const override;
+ int do_encoding() const _NOEXCEPT override;
+ bool do_always_noconv() const _NOEXCEPT override;
+ int do_length(state_type&, const extern_type* __frm, const extern_type* __end, size_t __mx) const override;
+ int do_max_length() const _NOEXCEPT override;
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Elem, unsigned long _Maxcode = 0x10ffff, codecvt_mode _Mode = (codecvt_mode)0>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 codecvt_utf8_utf16 : public __codecvt_utf8_utf16<_Elem> {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit codecvt_utf8_utf16(size_t __refs = 0)
+ : __codecvt_utf8_utf16<_Elem>(__refs, _Maxcode, _Mode) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~codecvt_utf8_utf16() {}
+};
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER < 26 || defined(_LIBCPP_BUILDING_LIBRARY) || defined(_LIBCPP_ENABLE_CXX26_REMOVED_CODECVT)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstddef>
+# include <cstdlib>
+# include <cstring>
+# include <initializer_list>
+# include <iosfwd>
+# include <limits>
+# include <mutex>
+# include <new>
+# include <stdexcept>
+# include <type_traits>
+# include <typeinfo>
+#endif
+
+#endif // _LIBCPP_CODECVT
diff --git a/libcxx/include/__cxx03/compare b/libcxx/include/__cxx03/compare
new file mode 100644
index 00000000000000..8a41835b148978
--- /dev/null
+++ b/libcxx/include/__cxx03/compare
@@ -0,0 +1,178 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_COMPARE
+#define _LIBCPP_COMPARE
+
+/*
+ compare synopsis
+
+namespace std {
+ // [cmp.categories], comparison category types
+ class partial_ordering;
+ class weak_ordering;
+ class strong_ordering;
+
+ // named comparison functions
+ constexpr bool is_eq (partial_ordering cmp) noexcept { return cmp == 0; }
+ constexpr bool is_neq (partial_ordering cmp) noexcept { return cmp != 0; }
+ constexpr bool is_lt (partial_ordering cmp) noexcept { return cmp < 0; }
+ constexpr bool is_lteq(partial_ordering cmp) noexcept { return cmp <= 0; }
+ constexpr bool is_gt (partial_ordering cmp) noexcept { return cmp > 0; }
+ constexpr bool is_gteq(partial_ordering cmp) noexcept { return cmp >= 0; }
+
+ // [cmp.common], common comparison category type
+ template<class... Ts>
+ struct common_comparison_category {
+ using type = see below;
+ };
+ template<class... Ts>
+ using common_comparison_category_t = typename common_comparison_category<Ts...>::type;
+
+ // [cmp.concept], concept three_way_comparable
+ template<class T, class Cat = partial_ordering>
+ concept three_way_comparable = see below;
+ template<class T, class U, class Cat = partial_ordering>
+ concept three_way_comparable_with = see below;
+
+ // [cmp.result], result of three-way comparison
+ template<class T, class U = T> struct compare_three_way_result;
+
+ template<class T, class U = T>
+ using compare_three_way_result_t = typename compare_three_way_result<T, U>::type;
+
+ // [comparisons.three.way], class compare_three_way
+ struct compare_three_way; // C++20
+
+ // [cmp.alg], comparison algorithms
+ inline namespace unspecified {
+ inline constexpr unspecified strong_order = unspecified;
+ inline constexpr unspecified weak_order = unspecified;
+ inline constexpr unspecified partial_order = unspecified;
+ inline constexpr unspecified compare_strong_order_fallback = unspecified;
+ inline constexpr unspecified compare_weak_order_fallback = unspecified;
+ inline constexpr unspecified compare_partial_order_fallback = unspecified;
+ }
+
+ // [cmp.partialord], Class partial_ordering
+ class partial_ordering {
+ public:
+ // valid values
+ static const partial_ordering less;
+ static const partial_ordering equivalent;
+ static const partial_ordering greater;
+ static const partial_ordering unordered;
+
+ // comparisons
+ friend constexpr bool operator==(partial_ordering v, unspecified) noexcept;
+ friend constexpr bool operator==(partial_ordering v, partial_ordering w) noexcept = default;
+ friend constexpr bool operator< (partial_ordering v, unspecified) noexcept;
+ friend constexpr bool operator> (partial_ordering v, unspecified) noexcept;
+ friend constexpr bool operator<=(partial_ordering v, unspecified) noexcept;
+ friend constexpr bool operator>=(partial_ordering v, unspecified) noexcept;
+ friend constexpr bool operator< (unspecified, partial_ordering v) noexcept;
+ friend constexpr bool operator> (unspecified, partial_ordering v) noexcept;
+ friend constexpr bool operator<=(unspecified, partial_ordering v) noexcept;
+ friend constexpr bool operator>=(unspecified, partial_ordering v) noexcept;
+ friend constexpr partial_ordering operator<=>(partial_ordering v, unspecified) noexcept;
+ friend constexpr partial_ordering operator<=>(unspecified, partial_ordering v) noexcept;
+ };
+
+ // [cmp.weakord], Class weak_ordering
+ class weak_ordering {
+ public:
+ // valid values
+ static const weak_ordering less;
+ static const weak_ordering equivalent;
+ static const weak_ordering greater;
+
+ // conversions
+ constexpr operator partial_ordering() const noexcept;
+
+ // comparisons
+ friend constexpr bool operator==(weak_ordering v, unspecified) noexcept;
+ friend constexpr bool operator==(weak_ordering v, weak_ordering w) noexcept = default;
+ friend constexpr bool operator< (weak_ordering v, unspecified) noexcept;
+ friend constexpr bool operator> (weak_ordering v, unspecified) noexcept;
+ friend constexpr bool operator<=(weak_ordering v, unspecified) noexcept;
+ friend constexpr bool operator>=(weak_ordering v, unspecified) noexcept;
+ friend constexpr bool operator< (unspecified, weak_ordering v) noexcept;
+ friend constexpr bool operator> (unspecified, weak_ordering v) noexcept;
+ friend constexpr bool operator<=(unspecified, weak_ordering v) noexcept;
+ friend constexpr bool operator>=(unspecified, weak_ordering v) noexcept;
+ friend constexpr weak_ordering operator<=>(weak_ordering v, unspecified) noexcept;
+ friend constexpr weak_ordering operator<=>(unspecified, weak_ordering v) noexcept;
+ };
+
+ // [cmp.strongord], Class strong_ordering
+ class strong_ordering {
+ public:
+ // valid values
+ static const strong_ordering less;
+ static const strong_ordering equal;
+ static const strong_ordering equivalent;
+ static const strong_ordering greater;
+
+ // conversions
+ constexpr operator partial_ordering() const noexcept;
+ constexpr operator weak_ordering() const noexcept;
+
+ // comparisons
+ friend constexpr bool operator==(strong_ordering v, unspecified) noexcept;
+ friend constexpr bool operator==(strong_ordering v, strong_ordering w) noexcept = default;
+ friend constexpr bool operator< (strong_ordering v, unspecified) noexcept;
+ friend constexpr bool operator> (strong_ordering v, unspecified) noexcept;
+ friend constexpr bool operator<=(strong_ordering v, unspecified) noexcept;
+ friend constexpr bool operator>=(strong_ordering v, unspecified) noexcept;
+ friend constexpr bool operator< (unspecified, strong_ordering v) noexcept;
+ friend constexpr bool operator> (unspecified, strong_ordering v) noexcept;
+ friend constexpr bool operator<=(unspecified, strong_ordering v) noexcept;
+ friend constexpr bool operator>=(unspecified, strong_ordering v) noexcept;
+ friend constexpr strong_ordering operator<=>(strong_ordering v, unspecified) noexcept;
+ friend constexpr strong_ordering operator<=>(unspecified, strong_ordering v) noexcept;
+ };
+}
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 20
+# include <__compare/common_comparison_category.h>
+# include <__compare/compare_partial_order_fallback.h>
+# include <__compare/compare_strong_order_fallback.h>
+# include <__compare/compare_three_way.h>
+# include <__compare/compare_three_way_result.h>
+# include <__compare/compare_weak_order_fallback.h>
+# include <__compare/is_eq.h>
+# include <__compare/ordering.h>
+# include <__compare/partial_order.h>
+# include <__compare/strong_order.h>
+# include <__compare/synth_three_way.h>
+# include <__compare/three_way_comparable.h>
+# include <__compare/weak_order.h>
+#endif // _LIBCPP_STD_VER >= 20
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <cstddef>
+# include <cstdint>
+# include <limits>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cmath>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_COMPARE
diff --git a/libcxx/include/__cxx03/complex b/libcxx/include/__cxx03/complex
new file mode 100644
index 00000000000000..e6534025de57e5
--- /dev/null
+++ b/libcxx/include/__cxx03/complex
@@ -0,0 +1,1480 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_COMPLEX
+#define _LIBCPP_COMPLEX
+
+/*
+ complex synopsis
+
+namespace std
+{
+
+template<class T>
+class complex
+{
+public:
+ typedef T value_type;
+
+ complex(const T& re = T(), const T& im = T()); // constexpr in C++14
+ complex(const complex&); // constexpr in C++14
+ template<class X> complex(const complex<X>&); // constexpr in C++14
+
+ T real() const; // constexpr in C++14
+ T imag() const; // constexpr in C++14
+
+ void real(T); // constexpr in C++20
+ void imag(T); // constexpr in C++20
+
+ complex<T>& operator= (const T&); // constexpr in C++20
+ complex<T>& operator+=(const T&); // constexpr in C++20
+ complex<T>& operator-=(const T&); // constexpr in C++20
+ complex<T>& operator*=(const T&); // constexpr in C++20
+ complex<T>& operator/=(const T&); // constexpr in C++20
+
+ complex& operator=(const complex&); // constexpr in C++20
+ template<class X> complex<T>& operator= (const complex<X>&); // constexpr in C++20
+ template<class X> complex<T>& operator+=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<T>& operator-=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<T>& operator*=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<T>& operator/=(const complex<X>&); // constexpr in C++20
+};
+
+template<>
+class complex<float>
+{
+public:
+ typedef float value_type;
+
+ constexpr complex(float re = 0.0f, float im = 0.0f);
+ explicit constexpr complex(const complex<double>&);
+ explicit constexpr complex(const complex<long double>&);
+
+ constexpr float real() const;
+ void real(float); // constexpr in C++20
+ constexpr float imag() const;
+ void imag(float); // constexpr in C++20
+
+ complex<float>& operator= (float); // constexpr in C++20
+ complex<float>& operator+=(float); // constexpr in C++20
+ complex<float>& operator-=(float); // constexpr in C++20
+ complex<float>& operator*=(float); // constexpr in C++20
+ complex<float>& operator/=(float); // constexpr in C++20
+
+ complex<float>& operator=(const complex<float>&); // constexpr in C++20
+ template<class X> complex<float>& operator= (const complex<X>&); // constexpr in C++20
+ template<class X> complex<float>& operator+=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<float>& operator-=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<float>& operator*=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<float>& operator/=(const complex<X>&); // constexpr in C++20
+};
+
+template<>
+class complex<double>
+{
+public:
+ typedef double value_type;
+
+ constexpr complex(double re = 0.0, double im = 0.0);
+ constexpr complex(const complex<float>&);
+ explicit constexpr complex(const complex<long double>&);
+
+ constexpr double real() const;
+ void real(double); // constexpr in C++20
+ constexpr double imag() const;
+ void imag(double); // constexpr in C++20
+
+ complex<double>& operator= (double); // constexpr in C++20
+ complex<double>& operator+=(double); // constexpr in C++20
+ complex<double>& operator-=(double); // constexpr in C++20
+ complex<double>& operator*=(double); // constexpr in C++20
+ complex<double>& operator/=(double); // constexpr in C++20
+ complex<double>& operator=(const complex<double>&); // constexpr in C++20
+
+ template<class X> complex<double>& operator= (const complex<X>&); // constexpr in C++20
+ template<class X> complex<double>& operator+=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<double>& operator-=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<double>& operator*=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<double>& operator/=(const complex<X>&); // constexpr in C++20
+};
+
+template<>
+class complex<long double>
+{
+public:
+ typedef long double value_type;
+
+ constexpr complex(long double re = 0.0L, long double im = 0.0L);
+ constexpr complex(const complex<float>&);
+ constexpr complex(const complex<double>&);
+
+ constexpr long double real() const;
+ void real(long double); // constexpr in C++20
+ constexpr long double imag() const;
+ void imag(long double); // constexpr in C++20
+
+ complex<long double>& operator=(const complex<long double>&); // constexpr in C++20
+ complex<long double>& operator= (long double); // constexpr in C++20
+ complex<long double>& operator+=(long double); // constexpr in C++20
+ complex<long double>& operator-=(long double); // constexpr in C++20
+ complex<long double>& operator*=(long double); // constexpr in C++20
+ complex<long double>& operator/=(long double); // constexpr in C++20
+
+ template<class X> complex<long double>& operator= (const complex<X>&); // constexpr in C++20
+ template<class X> complex<long double>& operator+=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<long double>& operator-=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<long double>& operator*=(const complex<X>&); // constexpr in C++20
+ template<class X> complex<long double>& operator/=(const complex<X>&); // constexpr in C++20
+};
+
+// 26.3.6 operators:
+template<class T> complex<T> operator+(const complex<T>&, const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator+(const complex<T>&, const T&); // constexpr in C++20
+template<class T> complex<T> operator+(const T&, const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator-(const complex<T>&, const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator-(const complex<T>&, const T&); // constexpr in C++20
+template<class T> complex<T> operator-(const T&, const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator*(const complex<T>&, const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator*(const complex<T>&, const T&); // constexpr in C++20
+template<class T> complex<T> operator*(const T&, const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator/(const complex<T>&, const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator/(const complex<T>&, const T&); // constexpr in C++20
+template<class T> complex<T> operator/(const T&, const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator+(const complex<T>&); // constexpr in C++20
+template<class T> complex<T> operator-(const complex<T>&); // constexpr in C++20
+template<class T> bool operator==(const complex<T>&, const complex<T>&); // constexpr in C++14
+template<class T> bool operator==(const complex<T>&, const T&); // constexpr in C++14
+template<class T> bool operator==(const T&, const complex<T>&); // constexpr in C++14, removed in C++20
+template<class T> bool operator!=(const complex<T>&, const complex<T>&); // constexpr in C++14, removed in C++20
+template<class T> bool operator!=(const complex<T>&, const T&); // constexpr in C++14, removed in C++20
+template<class T> bool operator!=(const T&, const complex<T>&); // constexpr in C++14, removed in C++20
+
+template<class T, class charT, class traits>
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>&, complex<T>&);
+template<class T, class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>&, const complex<T>&);
+
+// 26.3.7 values:
+
+template<class T> T real(const complex<T>&); // constexpr in C++14
+ long double real(long double); // constexpr in C++14
+ double real(double); // constexpr in C++14
+template<Integral T> double real(T); // constexpr in C++14
+ float real(float); // constexpr in C++14
+
+template<class T> T imag(const complex<T>&); // constexpr in C++14
+ long double imag(long double); // constexpr in C++14
+ double imag(double); // constexpr in C++14
+template<Integral T> double imag(T); // constexpr in C++14
+ float imag(float); // constexpr in C++14
+
+template<class T> T abs(const complex<T>&);
+
+template<class T> T arg(const complex<T>&);
+ long double arg(long double);
+ double arg(double);
+template<Integral T> double arg(T);
+ float arg(float);
+
+template<class T> T norm(const complex<T>&); // constexpr in C++20
+ long double norm(long double); // constexpr in C++20
+ double norm(double); // constexpr in C++20
+template<Integral T> double norm(T); // constexpr in C++20
+ float norm(float); // constexpr in C++20
+
+template<class T> complex<T> conj(const complex<T>&); // constexpr in C++20
+ complex<long double> conj(long double); // constexpr in C++20
+ complex<double> conj(double); // constexpr in C++20
+template<Integral T> complex<double> conj(T); // constexpr in C++20
+ complex<float> conj(float); // constexpr in C++20
+
+template<class T> complex<T> proj(const complex<T>&);
+ complex<long double> proj(long double);
+ complex<double> proj(double);
+template<Integral T> complex<double> proj(T);
+ complex<float> proj(float);
+
+template<class T> complex<T> polar(const T&, const T& = T());
+
+// 26.3.8 transcendentals:
+template<class T> complex<T> acos(const complex<T>&);
+template<class T> complex<T> asin(const complex<T>&);
+template<class T> complex<T> atan(const complex<T>&);
+template<class T> complex<T> acosh(const complex<T>&);
+template<class T> complex<T> asinh(const complex<T>&);
+template<class T> complex<T> atanh(const complex<T>&);
+template<class T> complex<T> cos (const complex<T>&);
+template<class T> complex<T> cosh (const complex<T>&);
+template<class T> complex<T> exp (const complex<T>&);
+template<class T> complex<T> log (const complex<T>&);
+template<class T> complex<T> log10(const complex<T>&);
+
+template<class T> complex<T> pow(const complex<T>&, const T&);
+template<class T> complex<T> pow(const complex<T>&, const complex<T>&);
+template<class T> complex<T> pow(const T&, const complex<T>&);
+
+template<class T> complex<T> sin (const complex<T>&);
+template<class T> complex<T> sinh (const complex<T>&);
+template<class T> complex<T> sqrt (const complex<T>&);
+template<class T> complex<T> tan (const complex<T>&);
+template<class T> complex<T> tanh (const complex<T>&);
+
+ // [complex.tuple], tuple interface
+ template<class T> struct tuple_size; // Since C++26
+ template<size_t I, class T> struct tuple_element; // Since C++26
+ template<class T> struct tuple_size<complex<T>>; // Since C++26
+ template<size_t I, class T> struct tuple_element<I, complex<T>>; // Since C++26
+ template<size_t I, class T>
+ constexpr T& get(complex<T>&) noexcept; // Since C++26
+ template<size_t I, class T>
+ constexpr T&& get(complex<T>&&) noexcept; // Since C++26
+ template<size_t I, class T>
+ constexpr const T& get(const complex<T>&) noexcept; // Since C++26
+ template<size_t I, class T>
+ constexpr const T&& get(const complex<T>&&) noexcept; // Since C++26
+
+ // [complex.literals], complex literals
+ inline namespace literals {
+ inline namespace complex_literals {
+ constexpr complex<long double> operator""il(long double); // Since C++14
+ constexpr complex<long double> operator""il(unsigned long long); // Since C++14
+ constexpr complex<double> operator""i(long double); // Since C++14
+ constexpr complex<double> operator""i(unsigned long long); // Since C++14
+ constexpr complex<float> operator""if(long double); // Since C++14
+ constexpr complex<float> operator""if(unsigned long long); // Since C++14
+ }
+ }
+} // std
+
+*/
+
+#include <__config>
+#include <__fwd/complex.h>
+#include <__fwd/tuple.h>
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_size.h>
+#include <__type_traits/conditional.h>
+#include <__utility/move.h>
+#include <cmath>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <sstream> // for std::basic_ostringstream
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS complex;
+
+template <class _Tp, __enable_if_t<is_floating_point<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator*(const complex<_Tp>& __z, const complex<_Tp>& __w);
+
+template <class _Tp, __enable_if_t<!is_floating_point<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator*(const complex<_Tp>& __z, const complex<_Tp>& __w);
+
+template <class _Tp, __enable_if_t<is_floating_point<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator/(const complex<_Tp>& __x, const complex<_Tp>& __y);
+
+template <class _Tp, __enable_if_t<!is_floating_point<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator/(const complex<_Tp>& __x, const complex<_Tp>& __y);
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS complex {
+public:
+ typedef _Tp value_type;
+
+private:
+ value_type __re_;
+ value_type __im_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
+ complex(const value_type& __re = value_type(), const value_type& __im = value_type())
+ : __re_(__re), __im_(__im) {}
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 complex(const complex<_Xp>& __c)
+ : __re_(__c.real()), __im_(__c.imag()) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 value_type real() const { return __re_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 value_type imag() const { return __im_; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void real(value_type __re) { __re_ = __re; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void imag(value_type __im) { __im_ = __im; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator=(const value_type& __re) {
+ __re_ = __re;
+ __im_ = value_type();
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator+=(const value_type& __re) {
+ __re_ += __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator-=(const value_type& __re) {
+ __re_ -= __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator*=(const value_type& __re) {
+ __re_ *= __re;
+ __im_ *= __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator/=(const value_type& __re) {
+ __re_ /= __re;
+ __im_ /= __re;
+ return *this;
+ }
+
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator=(const complex<_Xp>& __c) {
+ __re_ = __c.real();
+ __im_ = __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator+=(const complex<_Xp>& __c) {
+ __re_ += __c.real();
+ __im_ += __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator-=(const complex<_Xp>& __c) {
+ __re_ -= __c.real();
+ __im_ -= __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator*=(const complex<_Xp>& __c) {
+ *this = *this * complex(__c.real(), __c.imag());
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator/=(const complex<_Xp>& __c) {
+ *this = *this / complex(__c.real(), __c.imag());
+ return *this;
+ }
+
+#if _LIBCPP_STD_VER >= 26
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr _Xp& get(complex<_Xp>&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr _Xp&& get(complex<_Xp>&&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr const _Xp& get(const complex<_Xp>&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr const _Xp&& get(const complex<_Xp>&&) noexcept;
+#endif
+};
+
+template <>
+class _LIBCPP_TEMPLATE_VIS complex<double>;
+template <>
+class _LIBCPP_TEMPLATE_VIS complex<long double>;
+
+struct __from_builtin_tag {};
+
+template <class _Tp>
+using __complex_t =
+ __conditional_t<is_same<_Tp, float>::value,
+ _Complex float,
+ __conditional_t<is_same<_Tp, double>::value, _Complex double, _Complex long double> >;
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __complex_t<_Tp> __make_complex(_Tp __re, _Tp __im) {
+#if __has_builtin(__builtin_complex)
+ return __builtin_complex(__re, __im);
+#else
+ return __complex_t<_Tp>{__re, __im};
+#endif
+}
+
+template <>
+class _LIBCPP_TEMPLATE_VIS complex<float> {
+ float __re_;
+ float __im_;
+
+public:
+ typedef float value_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR complex(float __re = 0.0f, float __im = 0.0f) : __re_(__re), __im_(__im) {}
+
+ template <class _Tag, __enable_if_t<_IsSame<_Tag, __from_builtin_tag>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit complex(_Tag, _Complex float __v)
+ : __re_(__real__ __v), __im_(__imag__ __v) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit _LIBCPP_CONSTEXPR complex(const complex<double>& __c);
+ _LIBCPP_HIDE_FROM_ABI explicit _LIBCPP_CONSTEXPR complex(const complex<long double>& __c);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR float real() const { return __re_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR float imag() const { return __im_; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void real(value_type __re) { __re_ = __re; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void imag(value_type __im) { __im_ = __im; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Complex float __builtin() const { return std::__make_complex(__re_, __im_); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __builtin(_Complex float __f) {
+ __re_ = __real__ __f;
+ __im_ = __imag__ __f;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator=(float __re) {
+ __re_ = __re;
+ __im_ = value_type();
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator+=(float __re) {
+ __re_ += __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator-=(float __re) {
+ __re_ -= __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator*=(float __re) {
+ __re_ *= __re;
+ __im_ *= __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator/=(float __re) {
+ __re_ /= __re;
+ __im_ /= __re;
+ return *this;
+ }
+
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator=(const complex<_Xp>& __c) {
+ __re_ = __c.real();
+ __im_ = __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator+=(const complex<_Xp>& __c) {
+ __re_ += __c.real();
+ __im_ += __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator-=(const complex<_Xp>& __c) {
+ __re_ -= __c.real();
+ __im_ -= __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator*=(const complex<_Xp>& __c) {
+ *this = *this * complex(__c.real(), __c.imag());
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator/=(const complex<_Xp>& __c) {
+ *this = *this / complex(__c.real(), __c.imag());
+ return *this;
+ }
+
+#if _LIBCPP_STD_VER >= 26
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr _Xp& get(complex<_Xp>&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr _Xp&& get(complex<_Xp>&&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr const _Xp& get(const complex<_Xp>&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr const _Xp&& get(const complex<_Xp>&&) noexcept;
+#endif
+};
+
+template <>
+class _LIBCPP_TEMPLATE_VIS complex<double> {
+ double __re_;
+ double __im_;
+
+public:
+ typedef double value_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR complex(double __re = 0.0, double __im = 0.0) : __re_(__re), __im_(__im) {}
+
+ template <class _Tag, __enable_if_t<_IsSame<_Tag, __from_builtin_tag>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit complex(_Tag, _Complex double __v)
+ : __re_(__real__ __v), __im_(__imag__ __v) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR complex(const complex<float>& __c);
+ _LIBCPP_HIDE_FROM_ABI explicit _LIBCPP_CONSTEXPR complex(const complex<long double>& __c);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR double real() const { return __re_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR double imag() const { return __im_; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void real(value_type __re) { __re_ = __re; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void imag(value_type __im) { __im_ = __im; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Complex double __builtin() const {
+ return std::__make_complex(__re_, __im_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __builtin(_Complex double __f) {
+ __re_ = __real__ __f;
+ __im_ = __imag__ __f;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator=(double __re) {
+ __re_ = __re;
+ __im_ = value_type();
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator+=(double __re) {
+ __re_ += __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator-=(double __re) {
+ __re_ -= __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator*=(double __re) {
+ __re_ *= __re;
+ __im_ *= __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator/=(double __re) {
+ __re_ /= __re;
+ __im_ /= __re;
+ return *this;
+ }
+
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator=(const complex<_Xp>& __c) {
+ __re_ = __c.real();
+ __im_ = __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator+=(const complex<_Xp>& __c) {
+ __re_ += __c.real();
+ __im_ += __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator-=(const complex<_Xp>& __c) {
+ __re_ -= __c.real();
+ __im_ -= __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator*=(const complex<_Xp>& __c) {
+ *this = *this * complex(__c.real(), __c.imag());
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator/=(const complex<_Xp>& __c) {
+ *this = *this / complex(__c.real(), __c.imag());
+ return *this;
+ }
+
+#if _LIBCPP_STD_VER >= 26
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr _Xp& get(complex<_Xp>&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr _Xp&& get(complex<_Xp>&&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr const _Xp& get(const complex<_Xp>&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr const _Xp&& get(const complex<_Xp>&&) noexcept;
+#endif
+};
+
+template <>
+class _LIBCPP_TEMPLATE_VIS complex<long double> {
+ long double __re_;
+ long double __im_;
+
+public:
+ typedef long double value_type;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR complex(long double __re = 0.0L, long double __im = 0.0L)
+ : __re_(__re), __im_(__im) {}
+
+ template <class _Tag, __enable_if_t<_IsSame<_Tag, __from_builtin_tag>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit complex(_Tag, _Complex long double __v)
+ : __re_(__real__ __v), __im_(__imag__ __v) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR complex(const complex<float>& __c);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR complex(const complex<double>& __c);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR long double real() const { return __re_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR long double imag() const { return __im_; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void real(value_type __re) { __re_ = __re; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void imag(value_type __im) { __im_ = __im; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Complex long double __builtin() const {
+ return std::__make_complex(__re_, __im_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __builtin(_Complex long double __f) {
+ __re_ = __real__ __f;
+ __im_ = __imag__ __f;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator=(long double __re) {
+ __re_ = __re;
+ __im_ = value_type();
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator+=(long double __re) {
+ __re_ += __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator-=(long double __re) {
+ __re_ -= __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator*=(long double __re) {
+ __re_ *= __re;
+ __im_ *= __re;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator/=(long double __re) {
+ __re_ /= __re;
+ __im_ /= __re;
+ return *this;
+ }
+
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator=(const complex<_Xp>& __c) {
+ __re_ = __c.real();
+ __im_ = __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator+=(const complex<_Xp>& __c) {
+ __re_ += __c.real();
+ __im_ += __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator-=(const complex<_Xp>& __c) {
+ __re_ -= __c.real();
+ __im_ -= __c.imag();
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator*=(const complex<_Xp>& __c) {
+ *this = *this * complex(__c.real(), __c.imag());
+ return *this;
+ }
+ template <class _Xp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex& operator/=(const complex<_Xp>& __c) {
+ *this = *this / complex(__c.real(), __c.imag());
+ return *this;
+ }
+
+#if _LIBCPP_STD_VER >= 26
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr _Xp& get(complex<_Xp>&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr _Xp&& get(complex<_Xp>&&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr const _Xp& get(const complex<_Xp>&) noexcept;
+
+ template <size_t _Ip, class _Xp>
+ friend _LIBCPP_HIDE_FROM_ABI constexpr const _Xp&& get(const complex<_Xp>&&) noexcept;
+#endif
+};
+
+inline _LIBCPP_CONSTEXPR complex<float>::complex(const complex<double>& __c) : __re_(__c.real()), __im_(__c.imag()) {}
+
+inline _LIBCPP_CONSTEXPR complex<float>::complex(const complex<long double>& __c)
+ : __re_(__c.real()), __im_(__c.imag()) {}
+
+inline _LIBCPP_CONSTEXPR complex<double>::complex(const complex<float>& __c) : __re_(__c.real()), __im_(__c.imag()) {}
+
+inline _LIBCPP_CONSTEXPR complex<double>::complex(const complex<long double>& __c)
+ : __re_(__c.real()), __im_(__c.imag()) {}
+
+inline _LIBCPP_CONSTEXPR complex<long double>::complex(const complex<float>& __c)
+ : __re_(__c.real()), __im_(__c.imag()) {}
+
+inline _LIBCPP_CONSTEXPR complex<long double>::complex(const complex<double>& __c)
+ : __re_(__c.real()), __im_(__c.imag()) {}
+
+// 26.3.6 operators:
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator+(const complex<_Tp>& __x, const complex<_Tp>& __y) {
+ complex<_Tp> __t(__x);
+ __t += __y;
+ return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator+(const complex<_Tp>& __x, const _Tp& __y) {
+ complex<_Tp> __t(__x);
+ __t += __y;
+ return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator+(const _Tp& __x, const complex<_Tp>& __y) {
+ complex<_Tp> __t(__y);
+ __t += __x;
+ return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator-(const complex<_Tp>& __x, const complex<_Tp>& __y) {
+ complex<_Tp> __t(__x);
+ __t -= __y;
+ return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator-(const complex<_Tp>& __x, const _Tp& __y) {
+ complex<_Tp> __t(__x);
+ __t -= __y;
+ return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator-(const _Tp& __x, const complex<_Tp>& __y) {
+ complex<_Tp> __t(-__y);
+ __t += __x;
+ return __t;
+}
+
+template <class _Tp, __enable_if_t<is_floating_point<_Tp>::value, int> >
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator*(const complex<_Tp>& __lhs, const complex<_Tp>& __rhs) {
+ return complex<_Tp>(__from_builtin_tag(), __lhs.__builtin() * __rhs.__builtin());
+}
+
+template <class _Tp, __enable_if_t<!is_floating_point<_Tp>::value, int> >
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator*(const complex<_Tp>& __z, const complex<_Tp>& __w) {
+ _Tp __a = __z.real();
+ _Tp __b = __z.imag();
+ _Tp __c = __w.real();
+ _Tp __d = __w.imag();
+
+ return complex<_Tp>((__a * __c) - (__b * __d), (__a * __d) + (__b * __c));
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator*(const complex<_Tp>& __x, const _Tp& __y) {
+ complex<_Tp> __t(__x);
+ __t *= __y;
+ return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator*(const _Tp& __x, const complex<_Tp>& __y) {
+ complex<_Tp> __t(__y);
+ __t *= __x;
+ return __t;
+}
+
+template <class _Tp, __enable_if_t<is_floating_point<_Tp>::value, int> >
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator/(const complex<_Tp>& __lhs, const complex<_Tp>& __rhs) {
+ return complex<_Tp>(__from_builtin_tag(), __lhs.__builtin() / __rhs.__builtin());
+}
+
+template <class _Tp, __enable_if_t<!is_floating_point<_Tp>::value, int> >
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator/(const complex<_Tp>& __z, const complex<_Tp>& __w) {
+ _Tp __a = __z.real();
+ _Tp __b = __z.imag();
+ _Tp __c = __w.real();
+ _Tp __d = __w.imag();
+
+ _Tp __denom = __c * __c + __d * __d;
+ return complex<_Tp>((__a * __c + __b * __d) / __denom, (__b * __c - __a * __d) / __denom);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator/(const complex<_Tp>& __x, const _Tp& __y) {
+ return complex<_Tp>(__x.real() / __y, __x.imag() / __y);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp>
+operator/(const _Tp& __x, const complex<_Tp>& __y) {
+ complex<_Tp> __t(__x);
+ __t /= __y;
+ return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp> operator+(const complex<_Tp>& __x) {
+ return __x;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp> operator-(const complex<_Tp>& __x) {
+ return complex<_Tp>(-__x.real(), -__x.imag());
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator==(const complex<_Tp>& __x, const complex<_Tp>& __y) {
+ return __x.real() == __y.real() && __x.imag() == __y.imag();
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator==(const complex<_Tp>& __x, const _Tp& __y) {
+ return __x.real() == __y && __x.imag() == 0;
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator==(const _Tp& __x, const complex<_Tp>& __y) {
+ return __x == __y.real() && 0 == __y.imag();
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator!=(const complex<_Tp>& __x, const complex<_Tp>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator!=(const complex<_Tp>& __x, const _Tp& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator!=(const _Tp& __x, const complex<_Tp>& __y) {
+ return !(__x == __y);
+}
+
+#endif
+
+// 26.3.7 values:
+
+template <class _Tp, bool = is_integral<_Tp>::value, bool = is_floating_point<_Tp>::value >
+struct __libcpp_complex_overload_traits {};
+
+// Integral Types
+template <class _Tp>
+struct __libcpp_complex_overload_traits<_Tp, true, false> {
+ typedef double _ValueType;
+ typedef complex<double> _ComplexType;
+};
+
+// Floating point types
+template <class _Tp>
+struct __libcpp_complex_overload_traits<_Tp, false, true> {
+ typedef _Tp _ValueType;
+ typedef complex<_Tp> _ComplexType;
+};
+
+// real
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp real(const complex<_Tp>& __c) {
+ return __c.real();
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename __libcpp_complex_overload_traits<_Tp>::_ValueType
+real(_Tp __re) {
+ return __re;
+}
+
+// imag
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp imag(const complex<_Tp>& __c) {
+ return __c.imag();
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename __libcpp_complex_overload_traits<_Tp>::_ValueType
+imag(_Tp) {
+ return 0;
+}
+
+// abs
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _Tp abs(const complex<_Tp>& __c) {
+ return std::hypot(__c.real(), __c.imag());
+}
+
+// arg
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _Tp arg(const complex<_Tp>& __c) {
+ return std::atan2(__c.imag(), __c.real());
+}
+
+template <class _Tp, __enable_if_t<is_same<_Tp, long double>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI long double arg(_Tp __re) {
+ return std::atan2l(0.L, __re);
+}
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value || is_same<_Tp, double>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI double arg(_Tp __re) {
+ return std::atan2(0., __re);
+}
+
+template <class _Tp, __enable_if_t<is_same<_Tp, float>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI float arg(_Tp __re) {
+ return std::atan2f(0.F, __re);
+}
+
+// norm
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp norm(const complex<_Tp>& __c) {
+ if (std::__constexpr_isinf(__c.real()))
+ return std::abs(__c.real());
+ if (std::__constexpr_isinf(__c.imag()))
+ return std::abs(__c.imag());
+ return __c.real() * __c.real() + __c.imag() * __c.imag();
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename __libcpp_complex_overload_traits<_Tp>::_ValueType
+norm(_Tp __re) {
+ typedef typename __libcpp_complex_overload_traits<_Tp>::_ValueType _ValueType;
+ return static_cast<_ValueType>(__re) * __re;
+}
+
+// conj
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 complex<_Tp> conj(const complex<_Tp>& __c) {
+ return complex<_Tp>(__c.real(), -__c.imag());
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename __libcpp_complex_overload_traits<_Tp>::_ComplexType
+conj(_Tp __re) {
+ typedef typename __libcpp_complex_overload_traits<_Tp>::_ComplexType _ComplexType;
+ return _ComplexType(__re);
+}
+
+// proj
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI complex<_Tp> proj(const complex<_Tp>& __c) {
+ complex<_Tp> __r = __c;
+ if (std::__constexpr_isinf(__c.real()) || std::__constexpr_isinf(__c.imag()))
+ __r = complex<_Tp>(INFINITY, std::copysign(_Tp(0), __c.imag()));
+ return __r;
+}
+
+template <class _Tp, __enable_if_t<is_floating_point<_Tp>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __libcpp_complex_overload_traits<_Tp>::_ComplexType proj(_Tp __re) {
+ if (std::__constexpr_isinf(__re))
+ __re = std::abs(__re);
+ return complex<_Tp>(__re);
+}
+
+template <class _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI typename __libcpp_complex_overload_traits<_Tp>::_ComplexType proj(_Tp __re) {
+ typedef typename __libcpp_complex_overload_traits<_Tp>::_ComplexType _ComplexType;
+ return _ComplexType(__re);
+}
+
+// polar
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> polar(const _Tp& __rho, const _Tp& __theta = _Tp()) {
+ if (std::__constexpr_isnan(__rho) || std::signbit(__rho))
+ return complex<_Tp>(_Tp(NAN), _Tp(NAN));
+ if (std::__constexpr_isnan(__theta)) {
+ if (std::__constexpr_isinf(__rho))
+ return complex<_Tp>(__rho, __theta);
+ return complex<_Tp>(__theta, __theta);
+ }
+ if (std::__constexpr_isinf(__theta)) {
+ if (std::__constexpr_isinf(__rho))
+ return complex<_Tp>(__rho, _Tp(NAN));
+ return complex<_Tp>(_Tp(NAN), _Tp(NAN));
+ }
+ _Tp __x = __rho * std::cos(__theta);
+ if (std::__constexpr_isnan(__x))
+ __x = 0;
+ _Tp __y = __rho * std::sin(__theta);
+ if (std::__constexpr_isnan(__y))
+ __y = 0;
+ return complex<_Tp>(__x, __y);
+}
+
+// log
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI complex<_Tp> log(const complex<_Tp>& __x) {
+ return complex<_Tp>(std::log(std::abs(__x)), std::arg(__x));
+}
+
+// log10
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI complex<_Tp> log10(const complex<_Tp>& __x) {
+ return std::log(__x) / std::log(_Tp(10));
+}
+
+// sqrt
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> sqrt(const complex<_Tp>& __x) {
+ if (std::__constexpr_isinf(__x.imag()))
+ return complex<_Tp>(_Tp(INFINITY), __x.imag());
+ if (std::__constexpr_isinf(__x.real())) {
+ if (__x.real() > _Tp(0))
+ return complex<_Tp>(
+ __x.real(), std::__constexpr_isnan(__x.imag()) ? __x.imag() : std::copysign(_Tp(0), __x.imag()));
+ return complex<_Tp>(
+ std::__constexpr_isnan(__x.imag()) ? __x.imag() : _Tp(0), std::copysign(__x.real(), __x.imag()));
+ }
+ return std::polar(std::sqrt(std::abs(__x)), std::arg(__x) / _Tp(2));
+}
+
+// exp
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> exp(const complex<_Tp>& __x) {
+ _Tp __i = __x.imag();
+ if (__i == 0) {
+ return complex<_Tp>(std::exp(__x.real()), std::copysign(_Tp(0), __x.imag()));
+ }
+ if (std::__constexpr_isinf(__x.real())) {
+ if (__x.real() < _Tp(0)) {
+ if (!std::__constexpr_isfinite(__i))
+ __i = _Tp(1);
+ } else if (__i == 0 || !std::__constexpr_isfinite(__i)) {
+ if (std::__constexpr_isinf(__i))
+ __i = _Tp(NAN);
+ return complex<_Tp>(__x.real(), __i);
+ }
+ }
+ _Tp __e = std::exp(__x.real());
+ return complex<_Tp>(__e * std::cos(__i), __e * std::sin(__i));
+}
+
+// pow
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI complex<_Tp> pow(const complex<_Tp>& __x, const complex<_Tp>& __y) {
+ return std::exp(__y * std::log(__x));
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI complex<typename __promote<_Tp, _Up>::type>
+pow(const complex<_Tp>& __x, const complex<_Up>& __y) {
+ typedef complex<typename __promote<_Tp, _Up>::type> result_type;
+ return std::pow(result_type(__x), result_type(__y));
+}
+
+template <class _Tp, class _Up, __enable_if_t<is_arithmetic<_Up>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI complex<typename __promote<_Tp, _Up>::type> pow(const complex<_Tp>& __x, const _Up& __y) {
+ typedef complex<typename __promote<_Tp, _Up>::type> result_type;
+ return std::pow(result_type(__x), result_type(__y));
+}
+
+template <class _Tp, class _Up, __enable_if_t<is_arithmetic<_Tp>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI complex<typename __promote<_Tp, _Up>::type> pow(const _Tp& __x, const complex<_Up>& __y) {
+ typedef complex<typename __promote<_Tp, _Up>::type> result_type;
+ return std::pow(result_type(__x), result_type(__y));
+}
+
+// __sqr, computes pow(x, 2)
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI complex<_Tp> __sqr(const complex<_Tp>& __x) {
+ return complex<_Tp>((__x.real() - __x.imag()) * (__x.real() + __x.imag()), _Tp(2) * __x.real() * __x.imag());
+}
+
+// asinh
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> asinh(const complex<_Tp>& __x) {
+ const _Tp __pi(atan2(+0., -0.));
+ if (std::__constexpr_isinf(__x.real())) {
+ if (std::__constexpr_isnan(__x.imag()))
+ return __x;
+ if (std::__constexpr_isinf(__x.imag()))
+ return complex<_Tp>(__x.real(), std::copysign(__pi * _Tp(0.25), __x.imag()));
+ return complex<_Tp>(__x.real(), std::copysign(_Tp(0), __x.imag()));
+ }
+ if (std::__constexpr_isnan(__x.real())) {
+ if (std::__constexpr_isinf(__x.imag()))
+ return complex<_Tp>(__x.imag(), __x.real());
+ if (__x.imag() == 0)
+ return __x;
+ return complex<_Tp>(__x.real(), __x.real());
+ }
+ if (std::__constexpr_isinf(__x.imag()))
+ return complex<_Tp>(std::copysign(__x.imag(), __x.real()), std::copysign(__pi / _Tp(2), __x.imag()));
+ complex<_Tp> __z = std::log(__x + std::sqrt(std::__sqr(__x) + _Tp(1)));
+ return complex<_Tp>(std::copysign(__z.real(), __x.real()), std::copysign(__z.imag(), __x.imag()));
+}
+
+// acosh
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> acosh(const complex<_Tp>& __x) {
+ const _Tp __pi(atan2(+0., -0.));
+ if (std::__constexpr_isinf(__x.real())) {
+ if (std::__constexpr_isnan(__x.imag()))
+ return complex<_Tp>(std::abs(__x.real()), __x.imag());
+ if (std::__constexpr_isinf(__x.imag())) {
+ if (__x.real() > 0)
+ return complex<_Tp>(__x.real(), std::copysign(__pi * _Tp(0.25), __x.imag()));
+ else
+ return complex<_Tp>(-__x.real(), std::copysign(__pi * _Tp(0.75), __x.imag()));
+ }
+ if (__x.real() < 0)
+ return complex<_Tp>(-__x.real(), std::copysign(__pi, __x.imag()));
+ return complex<_Tp>(__x.real(), std::copysign(_Tp(0), __x.imag()));
+ }
+ if (std::__constexpr_isnan(__x.real())) {
+ if (std::__constexpr_isinf(__x.imag()))
+ return complex<_Tp>(std::abs(__x.imag()), __x.real());
+ return complex<_Tp>(__x.real(), __x.real());
+ }
+ if (std::__constexpr_isinf(__x.imag()))
+ return complex<_Tp>(std::abs(__x.imag()), std::copysign(__pi / _Tp(2), __x.imag()));
+ complex<_Tp> __z = std::log(__x + std::sqrt(std::__sqr(__x) - _Tp(1)));
+ return complex<_Tp>(std::copysign(__z.real(), _Tp(0)), std::copysign(__z.imag(), __x.imag()));
+}
+
+// atanh
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> atanh(const complex<_Tp>& __x) {
+ const _Tp __pi(atan2(+0., -0.));
+ if (std::__constexpr_isinf(__x.imag())) {
+ return complex<_Tp>(std::copysign(_Tp(0), __x.real()), std::copysign(__pi / _Tp(2), __x.imag()));
+ }
+ if (std::__constexpr_isnan(__x.imag())) {
+ if (std::__constexpr_isinf(__x.real()) || __x.real() == 0)
+ return complex<_Tp>(std::copysign(_Tp(0), __x.real()), __x.imag());
+ return complex<_Tp>(__x.imag(), __x.imag());
+ }
+ if (std::__constexpr_isnan(__x.real())) {
+ return complex<_Tp>(__x.real(), __x.real());
+ }
+ if (std::__constexpr_isinf(__x.real())) {
+ return complex<_Tp>(std::copysign(_Tp(0), __x.real()), std::copysign(__pi / _Tp(2), __x.imag()));
+ }
+ if (std::abs(__x.real()) == _Tp(1) && __x.imag() == _Tp(0)) {
+ return complex<_Tp>(std::copysign(_Tp(INFINITY), __x.real()), std::copysign(_Tp(0), __x.imag()));
+ }
+ complex<_Tp> __z = std::log((_Tp(1) + __x) / (_Tp(1) - __x)) / _Tp(2);
+ return complex<_Tp>(std::copysign(__z.real(), __x.real()), std::copysign(__z.imag(), __x.imag()));
+}
+
+// sinh
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> sinh(const complex<_Tp>& __x) {
+ if (std::__constexpr_isinf(__x.real()) && !std::__constexpr_isfinite(__x.imag()))
+ return complex<_Tp>(__x.real(), _Tp(NAN));
+ if (__x.real() == 0 && !std::__constexpr_isfinite(__x.imag()))
+ return complex<_Tp>(__x.real(), _Tp(NAN));
+ if (__x.imag() == 0 && !std::__constexpr_isfinite(__x.real()))
+ return __x;
+ return complex<_Tp>(std::sinh(__x.real()) * std::cos(__x.imag()), std::cosh(__x.real()) * std::sin(__x.imag()));
+}
+
+// cosh
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> cosh(const complex<_Tp>& __x) {
+ if (std::__constexpr_isinf(__x.real()) && !std::__constexpr_isfinite(__x.imag()))
+ return complex<_Tp>(std::abs(__x.real()), _Tp(NAN));
+ if (__x.real() == 0 && !std::__constexpr_isfinite(__x.imag()))
+ return complex<_Tp>(_Tp(NAN), __x.real());
+ if (__x.real() == 0 && __x.imag() == 0)
+ return complex<_Tp>(_Tp(1), __x.imag());
+ if (__x.imag() == 0 && !std::__constexpr_isfinite(__x.real()))
+ return complex<_Tp>(std::abs(__x.real()), __x.imag());
+ return complex<_Tp>(std::cosh(__x.real()) * std::cos(__x.imag()), std::sinh(__x.real()) * std::sin(__x.imag()));
+}
+
+// tanh
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> tanh(const complex<_Tp>& __x) {
+ if (std::__constexpr_isinf(__x.real())) {
+ if (!std::__constexpr_isfinite(__x.imag()))
+ return complex<_Tp>(std::copysign(_Tp(1), __x.real()), _Tp(0));
+ return complex<_Tp>(std::copysign(_Tp(1), __x.real()), std::copysign(_Tp(0), std::sin(_Tp(2) * __x.imag())));
+ }
+ if (std::__constexpr_isnan(__x.real()) && __x.imag() == 0)
+ return __x;
+ _Tp __2r(_Tp(2) * __x.real());
+ _Tp __2i(_Tp(2) * __x.imag());
+ _Tp __d(std::cosh(__2r) + std::cos(__2i));
+ _Tp __2rsh(std::sinh(__2r));
+ if (std::__constexpr_isinf(__2rsh) && std::__constexpr_isinf(__d))
+ return complex<_Tp>(__2rsh > _Tp(0) ? _Tp(1) : _Tp(-1), __2i > _Tp(0) ? _Tp(0) : _Tp(-0.));
+ return complex<_Tp>(__2rsh / __d, std::sin(__2i) / __d);
+}
+
+// asin
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> asin(const complex<_Tp>& __x) {
+ complex<_Tp> __z = std::asinh(complex<_Tp>(-__x.imag(), __x.real()));
+ return complex<_Tp>(__z.imag(), -__z.real());
+}
+
+// acos
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> acos(const complex<_Tp>& __x) {
+ const _Tp __pi(atan2(+0., -0.));
+ if (std::__constexpr_isinf(__x.real())) {
+ if (std::__constexpr_isnan(__x.imag()))
+ return complex<_Tp>(__x.imag(), __x.real());
+ if (std::__constexpr_isinf(__x.imag())) {
+ if (__x.real() < _Tp(0))
+ return complex<_Tp>(_Tp(0.75) * __pi, -__x.imag());
+ return complex<_Tp>(_Tp(0.25) * __pi, -__x.imag());
+ }
+ if (__x.real() < _Tp(0))
+ return complex<_Tp>(__pi, std::signbit(__x.imag()) ? -__x.real() : __x.real());
+ return complex<_Tp>(_Tp(0), std::signbit(__x.imag()) ? __x.real() : -__x.real());
+ }
+ if (std::__constexpr_isnan(__x.real())) {
+ if (std::__constexpr_isinf(__x.imag()))
+ return complex<_Tp>(__x.real(), -__x.imag());
+ return complex<_Tp>(__x.real(), __x.real());
+ }
+ if (std::__constexpr_isinf(__x.imag()))
+ return complex<_Tp>(__pi / _Tp(2), -__x.imag());
+ if (__x.real() == 0 && (__x.imag() == 0 || std::isnan(__x.imag())))
+ return complex<_Tp>(__pi / _Tp(2), -__x.imag());
+ complex<_Tp> __z = std::log(__x + std::sqrt(std::__sqr(__x) - _Tp(1)));
+ if (std::signbit(__x.imag()))
+ return complex<_Tp>(std::abs(__z.imag()), std::abs(__z.real()));
+ return complex<_Tp>(std::abs(__z.imag()), -std::abs(__z.real()));
+}
+
+// atan
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> atan(const complex<_Tp>& __x) {
+ complex<_Tp> __z = std::atanh(complex<_Tp>(-__x.imag(), __x.real()));
+ return complex<_Tp>(__z.imag(), -__z.real());
+}
+
+// sin
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> sin(const complex<_Tp>& __x) {
+ complex<_Tp> __z = std::sinh(complex<_Tp>(-__x.imag(), __x.real()));
+ return complex<_Tp>(__z.imag(), -__z.real());
+}
+
+// cos
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI complex<_Tp> cos(const complex<_Tp>& __x) {
+ return std::cosh(complex<_Tp>(-__x.imag(), __x.real()));
+}
+
+// tan
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI complex<_Tp> tan(const complex<_Tp>& __x) {
+ complex<_Tp> __z = std::tanh(complex<_Tp>(-__x.imag(), __x.real()));
+ return complex<_Tp>(__z.imag(), -__z.real());
+}
+
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+template <class _Tp, class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, complex<_Tp>& __x) {
+ if (__is.good()) {
+ std::ws(__is);
+ if (__is.peek() == _CharT('(')) {
+ __is.get();
+ _Tp __r;
+ __is >> __r;
+ if (!__is.fail()) {
+ std::ws(__is);
+ _CharT __c = __is.peek();
+ if (__c == _CharT(',')) {
+ __is.get();
+ _Tp __i;
+ __is >> __i;
+ if (!__is.fail()) {
+ std::ws(__is);
+ __c = __is.peek();
+ if (__c == _CharT(')')) {
+ __is.get();
+ __x = complex<_Tp>(__r, __i);
+ } else
+ __is.setstate(__is.failbit);
+ } else
+ __is.setstate(__is.failbit);
+ } else if (__c == _CharT(')')) {
+ __is.get();
+ __x = complex<_Tp>(__r, _Tp(0));
+ } else
+ __is.setstate(__is.failbit);
+ } else
+ __is.setstate(__is.failbit);
+ } else {
+ _Tp __r;
+ __is >> __r;
+ if (!__is.fail())
+ __x = complex<_Tp>(__r, _Tp(0));
+ else
+ __is.setstate(__is.failbit);
+ }
+ } else
+ __is.setstate(__is.failbit);
+ return __is;
+}
+
+template <class _Tp, class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const complex<_Tp>& __x) {
+ basic_ostringstream<_CharT, _Traits> __s;
+ __s.flags(__os.flags());
+ __s.imbue(__os.getloc());
+ __s.precision(__os.precision());
+ __s << '(' << __x.real() << ',' << __x.imag() << ')';
+ return __os << __s.str();
+}
+#endif // !_LIBCPP_HAS_NO_LOCALIZATION
+
+#if _LIBCPP_STD_VER >= 26
+
+// [complex.tuple], tuple interface
+
+template <class _Tp>
+struct tuple_size<complex<_Tp>> : integral_constant<size_t, 2> {};
+
+template <size_t _Ip, class _Tp>
+struct tuple_element<_Ip, complex<_Tp>> {
+ static_assert(_Ip < 2, "Index value is out of range.");
+ using type = _Tp;
+};
+
+template <size_t _Ip, class _Xp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Xp& get(complex<_Xp>& __z) noexcept {
+ static_assert(_Ip < 2, "Index value is out of range.");
+ if constexpr (_Ip == 0) {
+ return __z.__re_;
+ } else {
+ return __z.__im_;
+ }
+}
+
+template <size_t _Ip, class _Xp>
+_LIBCPP_HIDE_FROM_ABI constexpr _Xp&& get(complex<_Xp>&& __z) noexcept {
+ static_assert(_Ip < 2, "Index value is out of range.");
+ if constexpr (_Ip == 0) {
+ return std::move(__z.__re_);
+ } else {
+ return std::move(__z.__im_);
+ }
+}
+
+template <size_t _Ip, class _Xp>
+_LIBCPP_HIDE_FROM_ABI constexpr const _Xp& get(const complex<_Xp>& __z) noexcept {
+ static_assert(_Ip < 2, "Index value is out of range.");
+ if constexpr (_Ip == 0) {
+ return __z.__re_;
+ } else {
+ return __z.__im_;
+ }
+}
+
+template <size_t _Ip, class _Xp>
+_LIBCPP_HIDE_FROM_ABI constexpr const _Xp&& get(const complex<_Xp>&& __z) noexcept {
+ static_assert(_Ip < 2, "Index value is out of range.");
+ if constexpr (_Ip == 0) {
+ return std::move(__z.__re_);
+ } else {
+ return std::move(__z.__im_);
+ }
+}
+
+#endif // _LIBCPP_STD_VER >= 26
+
+#if _LIBCPP_STD_VER >= 14
+// Literal suffix for complex number literals [complex.literals]
+inline namespace literals {
+inline namespace complex_literals {
+_LIBCPP_HIDE_FROM_ABI inline constexpr complex<long double> operator""il(long double __im) { return {0.0l, __im}; }
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr complex<long double> operator""il(unsigned long long __im) {
+ return {0.0l, static_cast<long double>(__im)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr complex<double> operator""i(long double __im) {
+ return {0.0, static_cast<double>(__im)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr complex<double> operator""i(unsigned long long __im) {
+ return {0.0, static_cast<double>(__im)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr complex<float> operator""if(long double __im) {
+ return {0.0f, static_cast<float>(__im)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr complex<float> operator""if(unsigned long long __im) {
+ return {0.0f, static_cast<float>(__im)};
+}
+} // namespace complex_literals
+} // namespace literals
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <iosfwd>
+# include <stdexcept>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_COMPLEX
diff --git a/libcxx/include/__cxx03/complex.h b/libcxx/include/__cxx03/complex.h
new file mode 100644
index 00000000000000..a3da21c843f365
--- /dev/null
+++ b/libcxx/include/__cxx03/complex.h
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_COMPLEX_H
+#define _LIBCPP_COMPLEX_H
+
+/*
+ complex.h synopsis
+
+#include <ccomplex>
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifdef __cplusplus
+# include <ccomplex>
+#elif __has_include_next(<complex.h>)
+# include_next <complex.h>
+#endif
+
+#endif // _LIBCPP_COMPLEX_H
diff --git a/libcxx/include/__cxx03/concepts b/libcxx/include/__cxx03/concepts
new file mode 100644
index 00000000000000..e89d216a593725
--- /dev/null
+++ b/libcxx/include/__cxx03/concepts
@@ -0,0 +1,173 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CONCEPTS
+#define _LIBCPP_CONCEPTS
+
+/*
+ concepts synopsis
+namespace std {
+ // [concepts.lang], language-related concepts
+ // [concept.same], concept same_as
+ template<class T, class U>
+ concept same_as = see below;
+
+ // [concept.derived], concept derived_from
+ template<class Derived, class Base>
+ concept derived_from = see below;
+
+ // [concept.convertible], concept convertible_to
+ template<class From, class To>
+ concept convertible_to = see below;
+
+ // [concept.commonref], concept common_reference_with
+ template<class T, class U>
+ concept common_reference_with = see below;
+
+ // [concept.common], concept common_with
+ template<class T, class U>
+ concept common_with = see below;
+
+ // [concepts.arithmetic], arithmetic concepts
+ template<class T>
+ concept integral = see below;
+ template<class T>
+ concept signed_integral = see below;
+ template<class T>
+ concept unsigned_integral = see below;
+ template<class T>
+ concept floating_point = see below;
+
+ // [concept.assignable], concept assignable_from
+ template<class LHS, class RHS>
+ concept assignable_from = see below;
+
+ // [concept.swappable], concept swappable
+ namespace ranges {
+ inline namespace unspecified {
+ inline constexpr unspecified swap = unspecified;
+ }
+ }
+ template<class T>
+ concept swappable = see below;
+ template<class T, class U>
+ concept swappable_with = see below;
+
+ // [concept.destructible], concept destructible
+ template<class T>
+ concept destructible = see below;
+
+ // [concept.constructible], concept constructible_from
+ template<class T, class... Args>
+ concept constructible_from = see below;
+
+ // [concept.default.init], concept default_initializable
+ template<class T>
+ concept default_initializable = see below;
+
+ // [concept.moveconstructible], concept move_constructible
+ template<class T>
+ concept move_constructible = see below;
+
+ // [concept.copyconstructible], concept copy_constructible
+ template<class T>
+ concept copy_constructible = see below;
+
+ // [concept.equalitycomparable], concept equality_comparable
+ template<class T>
+ concept equality_comparable = see below;
+ template<class T, class U>
+ concept equality_comparable_with = see below;
+
+ // [concept.totallyordered], concept totally_ordered
+ template<class T>
+ concept totally_ordered = see below;
+ template<class T, class U>
+ concept totally_ordered_with = see below;
+
+ // [concepts.object], object concepts
+ template<class T>
+ concept movable = see below;
+ template<class T>
+ concept copyable = see below;
+ template<class T>
+ concept semiregular = see below;
+ template<class T>
+ concept regular = see below;
+
+ // [concepts.callable], callable concepts
+ // [concept.invocable], concept invocable
+ template<class F, class... Args>
+ concept invocable = see below;
+
+ // [concept.regularinvocable], concept regular_invocable
+ template<class F, class... Args>
+ concept regular_invocable = see below;
+
+ // [concept.predicate], concept predicate
+ template<class F, class... Args>
+ concept predicate = see below;
+
+ // [concept.relation], concept relation
+ template<class R, class T, class U>
+ concept relation = see below;
+
+ // [concept.equiv], concept equivalence_relation
+ template<class R, class T, class U>
+ concept equivalence_relation = see below;
+
+ // [concept.strictweakorder], concept strict_weak_order
+ template<class R, class T, class U>
+ concept strict_weak_order = see below;
+}
+
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 20
+# include <__concepts/arithmetic.h>
+# include <__concepts/assignable.h>
+# include <__concepts/boolean_testable.h>
+# include <__concepts/class_or_enum.h>
+# include <__concepts/common_reference_with.h>
+# include <__concepts/common_with.h>
+# include <__concepts/constructible.h>
+# include <__concepts/convertible_to.h>
+# include <__concepts/copyable.h>
+# include <__concepts/derived_from.h>
+# include <__concepts/destructible.h>
+# include <__concepts/different_from.h>
+# include <__concepts/equality_comparable.h>
+# include <__concepts/invocable.h>
+# include <__concepts/movable.h>
+# include <__concepts/predicate.h>
+# include <__concepts/regular.h>
+# include <__concepts/relation.h>
+# include <__concepts/same_as.h>
+# include <__concepts/semiregular.h>
+# include <__concepts/swappable.h>
+# include <__concepts/totally_ordered.h>
+#endif // _LIBCPP_STD_VER >= 20
+
+#include <version>
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <cstddef>
+#endif
+
+#if _LIBCPP_STD_VER <= 20 && !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES)
+# include <type_traits>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#endif // _LIBCPP_CONCEPTS
diff --git a/libcxx/include/__cxx03/condition_variable b/libcxx/include/__cxx03/condition_variable
new file mode 100644
index 00000000000000..5195cd6057dd33
--- /dev/null
+++ b/libcxx/include/__cxx03/condition_variable
@@ -0,0 +1,369 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CONDITION_VARIABLE
+#define _LIBCPP_CONDITION_VARIABLE
+
+/*
+ condition_variable synopsis
+
+namespace std
+{
+
+enum class cv_status { no_timeout, timeout };
+
+class condition_variable
+{
+public:
+ condition_variable();
+ ~condition_variable();
+
+ condition_variable(const condition_variable&) = delete;
+ condition_variable& operator=(const condition_variable&) = delete;
+
+ void notify_one() noexcept;
+ void notify_all() noexcept;
+
+ void wait(unique_lock<mutex>& lock);
+ template <class Predicate>
+ void wait(unique_lock<mutex>& lock, Predicate pred);
+
+ template <class Clock, class Duration>
+ cv_status
+ wait_until(unique_lock<mutex>& lock,
+ const chrono::time_point<Clock, Duration>& abs_time);
+
+ template <class Clock, class Duration, class Predicate>
+ bool
+ wait_until(unique_lock<mutex>& lock,
+ const chrono::time_point<Clock, Duration>& abs_time,
+ Predicate pred);
+
+ template <class Rep, class Period>
+ cv_status
+ wait_for(unique_lock<mutex>& lock,
+ const chrono::duration<Rep, Period>& rel_time);
+
+ template <class Rep, class Period, class Predicate>
+ bool
+ wait_for(unique_lock<mutex>& lock,
+ const chrono::duration<Rep, Period>& rel_time,
+ Predicate pred);
+
+ typedef pthread_cond_t* native_handle_type;
+ native_handle_type native_handle();
+};
+
+void notify_all_at_thread_exit(condition_variable& cond, unique_lock<mutex> lk);
+
+class condition_variable_any
+{
+public:
+ condition_variable_any();
+ ~condition_variable_any();
+
+ condition_variable_any(const condition_variable_any&) = delete;
+ condition_variable_any& operator=(const condition_variable_any&) = delete;
+
+ void notify_one() noexcept;
+ void notify_all() noexcept;
+
+ template <class Lock>
+ void wait(Lock& lock);
+ template <class Lock, class Predicate>
+ void wait(Lock& lock, Predicate pred);
+
+ template <class Lock, class Clock, class Duration>
+ cv_status
+ wait_until(Lock& lock,
+ const chrono::time_point<Clock, Duration>& abs_time);
+
+ template <class Lock, class Clock, class Duration, class Predicate>
+ bool
+ wait_until(Lock& lock,
+ const chrono::time_point<Clock, Duration>& abs_time,
+ Predicate pred);
+
+ template <class Lock, class Rep, class Period>
+ cv_status
+ wait_for(Lock& lock,
+ const chrono::duration<Rep, Period>& rel_time);
+
+ template <class Lock, class Rep, class Period, class Predicate>
+ bool
+ wait_for(Lock& lock,
+ const chrono::duration<Rep, Period>& rel_time,
+ Predicate pred);
+
+ // [thread.condvarany.intwait], interruptible waits
+ template <class Lock, class Predicate>
+ bool wait(Lock& lock, stop_token stoken, Predicate pred); // since C++20
+
+ template <class Lock, class Clock, class Duration, class Predicate>
+ bool wait_until(Lock& lock, stop_token stoken,
+ const chrono::time_point<Clock, Duration>& abs_time, Predicate pred); // since C++20
+
+ template <class Lock, class Rep, class Period, class Predicate>
+ bool wait_for(Lock& lock, stop_token stoken,
+ const chrono::duration<Rep, Period>& rel_time, Predicate pred); // since C++20
+};
+
+} // std
+
+*/
+
+#include <__chrono/duration.h>
+#include <__chrono/steady_clock.h>
+#include <__chrono/time_point.h>
+#include <__condition_variable/condition_variable.h>
+#include <__config>
+#include <__memory/shared_ptr.h>
+#include <__mutex/lock_guard.h>
+#include <__mutex/mutex.h>
+#include <__mutex/tag_types.h>
+#include <__mutex/unique_lock.h>
+#include <__stop_token/stop_callback.h>
+#include <__stop_token/stop_token.h>
+#include <__utility/move.h>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_EXPORTED_FROM_ABI condition_variable_any {
+ condition_variable __cv_;
+ shared_ptr<mutex> __mut_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI condition_variable_any();
+
+ _LIBCPP_HIDE_FROM_ABI void notify_one() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI void notify_all() _NOEXCEPT;
+
+ template <class _Lock>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS void wait(_Lock& __lock);
+ template <class _Lock, class _Predicate>
+ _LIBCPP_HIDE_FROM_ABI void wait(_Lock& __lock, _Predicate __pred);
+
+ template <class _Lock, class _Clock, class _Duration>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS cv_status
+ wait_until(_Lock& __lock, const chrono::time_point<_Clock, _Duration>& __t);
+
+ template <class _Lock, class _Clock, class _Duration, class _Predicate>
+ bool _LIBCPP_HIDE_FROM_ABI
+ wait_until(_Lock& __lock, const chrono::time_point<_Clock, _Duration>& __t, _Predicate __pred);
+
+ template <class _Lock, class _Rep, class _Period>
+ cv_status _LIBCPP_HIDE_FROM_ABI wait_for(_Lock& __lock, const chrono::duration<_Rep, _Period>& __d);
+
+ template <class _Lock, class _Rep, class _Period, class _Predicate>
+ bool _LIBCPP_HIDE_FROM_ABI wait_for(_Lock& __lock, const chrono::duration<_Rep, _Period>& __d, _Predicate __pred);
+
+# if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN)
+
+ template <class _Lock, class _Predicate>
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool wait(_Lock& __lock, stop_token __stoken, _Predicate __pred);
+
+ template <class _Lock, class _Clock, class _Duration, class _Predicate>
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool wait_until(
+ _Lock& __lock, stop_token __stoken, const chrono::time_point<_Clock, _Duration>& __abs_time, _Predicate __pred);
+
+ template <class _Lock, class _Rep, class _Period, class _Predicate>
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool
+ wait_for(_Lock& __lock, stop_token __stoken, const chrono::duration<_Rep, _Period>& __rel_time, _Predicate __pred);
+
+# endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN)
+};
+
+inline condition_variable_any::condition_variable_any() : __mut_(make_shared<mutex>()) {}
+
+inline void condition_variable_any::notify_one() _NOEXCEPT {
+ { lock_guard<mutex> __lx(*__mut_); }
+ __cv_.notify_one();
+}
+
+inline void condition_variable_any::notify_all() _NOEXCEPT {
+ { lock_guard<mutex> __lx(*__mut_); }
+ __cv_.notify_all();
+}
+
+template <class _Lock>
+struct __unlock_guard {
+ _Lock& __lock_;
+
+ _LIBCPP_HIDE_FROM_ABI __unlock_guard(_Lock& __lock) : __lock_(__lock) { __lock_.unlock(); }
+
+ _LIBCPP_HIDE_FROM_ABI ~__unlock_guard() _NOEXCEPT // turns exception to std::terminate
+ {
+ __lock_.lock();
+ }
+
+ __unlock_guard(const __unlock_guard&) = delete;
+ __unlock_guard& operator=(const __unlock_guard&) = delete;
+};
+
+template <class _Lock>
+void condition_variable_any::wait(_Lock& __lock) {
+ shared_ptr<mutex> __mut = __mut_;
+ unique_lock<mutex> __lk(*__mut);
+ __unlock_guard<_Lock> __unlock(__lock);
+ lock_guard<unique_lock<mutex> > __lx(__lk, adopt_lock_t());
+ __cv_.wait(__lk);
+} // __mut_.unlock(), __lock.lock()
+
+template <class _Lock, class _Predicate>
+inline void condition_variable_any::wait(_Lock& __lock, _Predicate __pred) {
+ while (!__pred())
+ wait(__lock);
+}
+
+template <class _Lock, class _Clock, class _Duration>
+cv_status condition_variable_any::wait_until(_Lock& __lock, const chrono::time_point<_Clock, _Duration>& __t) {
+ shared_ptr<mutex> __mut = __mut_;
+ unique_lock<mutex> __lk(*__mut);
+ __unlock_guard<_Lock> __unlock(__lock);
+ lock_guard<unique_lock<mutex> > __lx(__lk, adopt_lock_t());
+ return __cv_.wait_until(__lk, __t);
+} // __mut_.unlock(), __lock.lock()
+
+template <class _Lock, class _Clock, class _Duration, class _Predicate>
+inline bool
+condition_variable_any::wait_until(_Lock& __lock, const chrono::time_point<_Clock, _Duration>& __t, _Predicate __pred) {
+ while (!__pred())
+ if (wait_until(__lock, __t) == cv_status::timeout)
+ return __pred();
+ return true;
+}
+
+template <class _Lock, class _Rep, class _Period>
+inline cv_status condition_variable_any::wait_for(_Lock& __lock, const chrono::duration<_Rep, _Period>& __d) {
+ return wait_until(__lock, chrono::steady_clock::now() + __d);
+}
+
+template <class _Lock, class _Rep, class _Period, class _Predicate>
+inline bool
+condition_variable_any::wait_for(_Lock& __lock, const chrono::duration<_Rep, _Period>& __d, _Predicate __pred) {
+ return wait_until(__lock, chrono::steady_clock::now() + __d, std::move(__pred));
+}
+
+# if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN)
+
+template <class _Lock, class _Predicate>
+bool condition_variable_any::wait(_Lock& __user_lock, stop_token __stoken, _Predicate __pred) {
+ if (__stoken.stop_requested())
+ return __pred();
+
+ // Per https://eel.is/c++draft/thread.condition.condvarany#general-note-2,
+ // we do need to take a copy of the shared pointer __mut_
+ // This ensures that a thread can call the destructor immediately after calling
+ // notify_all, without waiting all the wait calls.
+ // A thread can also safely call the destructor immediately after calling
+ // request_stop, as the call to request_stop would evaluate the callback,
+ // which accesses the internal condition variable, immediately on the same thread.
+ // In this situation, it is OK even without copying a shared ownership the internal
+ // condition variable. However, this needs the evaluation of stop_callback to
+ // happen-before the destruction.
+ // The spec only says "Only the notification to unblock the wait needs to happen
+ // before destruction". To make this work, we need to copy the shared ownership of
+ // the internal condition variable inside this function, which is not possible
+ // with the current ABI.
+ shared_ptr<mutex> __mut = __mut_;
+
+ stop_callback __cb(__stoken, [this] { notify_all(); });
+
+ while (true) {
+ if (__pred())
+ return true;
+
+ // We need to take the internal lock before checking stop_requested,
+ // so that the notification cannot come in between the stop_requested
+ // check and entering the wait.
+ // Note that the stop_callback takes the same internal lock before notifying
+ unique_lock<mutex> __internal_lock(*__mut);
+ if (__stoken.stop_requested())
+ break;
+
+ __unlock_guard<_Lock> __unlock(__user_lock);
+ unique_lock<mutex> __internal_lock2(
+ std::move(__internal_lock)); // switch unlock order between __internal_lock and __user_lock
+ __cv_.wait(__internal_lock2);
+ } // __internal_lock2.unlock(), __user_lock.lock()
+ return __pred();
+}
+
+template <class _Lock, class _Clock, class _Duration, class _Predicate>
+bool condition_variable_any::wait_until(
+ _Lock& __user_lock,
+ stop_token __stoken,
+ const chrono::time_point<_Clock, _Duration>& __abs_time,
+ _Predicate __pred) {
+ if (__stoken.stop_requested())
+ return __pred();
+
+ shared_ptr<mutex> __mut = __mut_;
+ stop_callback __cb(__stoken, [this] { notify_all(); });
+
+ while (true) {
+ if (__pred())
+ return true;
+
+ unique_lock<mutex> __internal_lock(*__mut);
+ if (__stoken.stop_requested())
+ break;
+
+ __unlock_guard<_Lock> __unlock(__user_lock);
+ unique_lock<mutex> __internal_lock2(
+ std::move(__internal_lock)); // switch unlock order between __internal_lock and __user_lock
+
+ if (__cv_.wait_until(__internal_lock2, __abs_time) == cv_status::timeout)
+ break;
+ } // __internal_lock2.unlock(), __user_lock.lock()
+ return __pred();
+}
+
+template <class _Lock, class _Rep, class _Period, class _Predicate>
+bool condition_variable_any::wait_for(
+ _Lock& __lock, stop_token __stoken, const chrono::duration<_Rep, _Period>& __rel_time, _Predicate __pred) {
+ return wait_until(__lock, std::move(__stoken), chrono::steady_clock::now() + __rel_time, std::move(__pred));
+}
+
+# endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN)
+
+_LIBCPP_EXPORTED_FROM_ABI void notify_all_at_thread_exit(condition_variable&, unique_lock<mutex>);
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !_LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstdint>
+# include <cstdlib>
+# include <cstring>
+# include <initializer_list>
+# include <iosfwd>
+# include <new>
+# include <stdexcept>
+# include <system_error>
+# include <type_traits>
+# include <typeinfo>
+#endif
+
+#endif // _LIBCPP_CONDITION_VARIABLE
diff --git a/libcxx/include/__cxx03/coroutine b/libcxx/include/__cxx03/coroutine
new file mode 100644
index 00000000000000..ee54388ad5aaf8
--- /dev/null
+++ b/libcxx/include/__cxx03/coroutine
@@ -0,0 +1,67 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_COROUTINE
+#define _LIBCPP_COROUTINE
+
+/**
+ coroutine synopsis
+
+namespace std {
+// [coroutine.traits]
+template <class R, class... ArgTypes>
+ struct coroutine_traits;
+// [coroutine.handle]
+template <class Promise = void>
+ struct coroutine_handle;
+// [coroutine.handle.compare]
+constexpr bool operator==(coroutine_handle<> x, coroutine_handle<> y) noexcept;
+constexpr strong_ordering operator<=>(coroutine_handle<> x, coroutine_handle<> y) noexcept;
+// [coroutine.handle.hash]
+template <class T> struct hash;
+template <class P> struct hash<coroutine_handle<P>>;
+// [coroutine.noop]
+struct noop_coroutine_promise;
+template<> struct coroutine_handle<noop_coroutine_promise>;
+using noop_coroutine_handle = coroutine_handle<noop_coroutine_promise>;
+noop_coroutine_handle noop_coroutine() noexcept;
+// [coroutine.trivial.awaitables]
+struct suspend_never;
+struct suspend_always;
+} // namespace std
+
+ */
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 20
+# include <__coroutine/coroutine_handle.h>
+# include <__coroutine/coroutine_traits.h>
+# include <__coroutine/noop_coroutine_handle.h>
+# include <__coroutine/trivial_awaitables.h>
+#endif // _LIBCPP_STD_VER >= 20
+
+#include <version>
+
+// standard-mandated includes
+
+// [coroutine.syn]
+#include <compare>
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <iosfwd>
+# include <limits>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_COROUTINE
diff --git a/libcxx/include/__cxx03/csetjmp b/libcxx/include/__cxx03/csetjmp
new file mode 100644
index 00000000000000..7ba90068710aea
--- /dev/null
+++ b/libcxx/include/__cxx03/csetjmp
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSETJMP
+#define _LIBCPP_CSETJMP
+
+/*
+ csetjmp synopsis
+
+Macros:
+
+ setjmp
+
+namespace std
+{
+
+Types:
+
+ jmp_buf
+
+void longjmp(jmp_buf env, int val);
+
+} // std
+
+*/
+
+#include <__config>
+
+// <setjmp.h> is not provided by libc++
+#if __has_include(<setjmp.h>)
+# include <setjmp.h>
+# ifdef _LIBCPP_SETJMP_H
+# error "If libc++ starts defining <setjmp.h>, the __has_include check should move to libc++'s <setjmp.h>"
+# endif
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::jmp_buf _LIBCPP_USING_IF_EXISTS;
+using ::longjmp _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CSETJMP
diff --git a/libcxx/include/__cxx03/csignal b/libcxx/include/__cxx03/csignal
new file mode 100644
index 00000000000000..804a7f95ae9682
--- /dev/null
+++ b/libcxx/include/__cxx03/csignal
@@ -0,0 +1,64 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSIGNAL
+#define _LIBCPP_CSIGNAL
+
+/*
+ csignal synopsis
+
+Macros:
+
+ SIG_DFL
+ SIG_ERR
+ SIG_IGN
+ SIGABRT
+ SIGFPE
+ SIGILL
+ SIGINT
+ SIGSEGV
+ SIGTERM
+
+namespace std
+{
+
+Types:
+
+ sig_atomic_t
+
+void (*signal(int sig, void (*func)(int)))(int);
+int raise(int sig);
+
+} // std
+
+*/
+
+#include <__config>
+
+// <signal.h> is not provided by libc++
+#if __has_include(<signal.h>)
+# include <signal.h>
+# ifdef _LIBCPP_SIGNAL_H
+# error "If libc++ starts defining <signal.h>, the __has_include check should move to libc++'s <signal.h>"
+# endif
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::sig_atomic_t _LIBCPP_USING_IF_EXISTS;
+using ::signal _LIBCPP_USING_IF_EXISTS;
+using ::raise _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CSIGNAL
diff --git a/libcxx/include/__cxx03/cstdarg b/libcxx/include/__cxx03/cstdarg
new file mode 100644
index 00000000000000..4642eb7b5258ca
--- /dev/null
+++ b/libcxx/include/__cxx03/cstdarg
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSTDARG
+#define _LIBCPP_CSTDARG
+
+/*
+ cstdarg synopsis
+
+Macros:
+
+ type va_arg(va_list ap, type);
+ void va_copy(va_list dest, va_list src); // C99
+ void va_end(va_list ap);
+ void va_start(va_list ap, parmN);
+
+namespace std
+{
+
+Types:
+
+ va_list
+
+} // std
+
+*/
+
+#include <__config>
+
+// <stdarg.h> is not provided by libc++
+#if __has_include(<stdarg.h>)
+# include <stdarg.h>
+# ifdef _LIBCPP_STDARG_H
+# error "If libc++ starts defining <stdarg.h>, the __has_include check should move to libc++'s <stdarg.h>"
+# endif
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::va_list _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CSTDARG
diff --git a/libcxx/include/__cxx03/cstdbool b/libcxx/include/__cxx03/cstdbool
new file mode 100644
index 00000000000000..ef731c021a4ab8
--- /dev/null
+++ b/libcxx/include/__cxx03/cstdbool
@@ -0,0 +1,31 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSTDBOOL
+#define _LIBCPP_CSTDBOOL
+
+/*
+ cstdbool synopsis
+
+Macros:
+
+ __bool_true_false_are_defined
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#undef __bool_true_false_are_defined
+#define __bool_true_false_are_defined 1
+
+#endif // _LIBCPP_CSTDBOOL
diff --git a/libcxx/include/__cxx03/cstddef b/libcxx/include/__cxx03/cstddef
new file mode 100644
index 00000000000000..1a4049e4d34f2d
--- /dev/null
+++ b/libcxx/include/__cxx03/cstddef
@@ -0,0 +1,133 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSTDDEF
+#define _LIBCPP_CSTDDEF
+
+/*
+ cstddef synopsis
+
+Macros:
+
+ offsetof(type,member-designator)
+ NULL
+
+namespace std
+{
+
+Types:
+
+ ptrdiff_t
+ size_t
+ max_align_t // C++11
+ nullptr_t
+ byte // C++17
+
+} // std
+
+*/
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_integral.h>
+#include <version>
+
+#include <stddef.h>
+
+#ifndef _LIBCPP_STDDEF_H
+# error <cstddef> tried including <stddef.h> but didn't find libc++'s <stddef.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::nullptr_t;
+using ::ptrdiff_t _LIBCPP_USING_IF_EXISTS;
+using ::size_t _LIBCPP_USING_IF_EXISTS;
+
+#if !defined(_LIBCPP_CXX03_LANG)
+using ::max_align_t _LIBCPP_USING_IF_EXISTS;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+namespace std // purposefully not versioned
+{
+enum class byte : unsigned char {};
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr byte operator|(byte __lhs, byte __rhs) noexcept {
+ return static_cast<byte>(
+ static_cast<unsigned char>(static_cast<unsigned int>(__lhs) | static_cast<unsigned int>(__rhs)));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr byte& operator|=(byte& __lhs, byte __rhs) noexcept {
+ return __lhs = __lhs | __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr byte operator&(byte __lhs, byte __rhs) noexcept {
+ return static_cast<byte>(
+ static_cast<unsigned char>(static_cast<unsigned int>(__lhs) & static_cast<unsigned int>(__rhs)));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr byte& operator&=(byte& __lhs, byte __rhs) noexcept {
+ return __lhs = __lhs & __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr byte operator^(byte __lhs, byte __rhs) noexcept {
+ return static_cast<byte>(
+ static_cast<unsigned char>(static_cast<unsigned int>(__lhs) ^ static_cast<unsigned int>(__rhs)));
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr byte& operator^=(byte& __lhs, byte __rhs) noexcept {
+ return __lhs = __lhs ^ __rhs;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline constexpr byte operator~(byte __b) noexcept {
+ return static_cast<byte>(static_cast<unsigned char>(~static_cast<unsigned int>(__b)));
+}
+
+template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr byte& operator<<=(byte& __lhs, _Integer __shift) noexcept {
+ return __lhs = __lhs << __shift;
+}
+
+template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr byte operator<<(byte __lhs, _Integer __shift) noexcept {
+ return static_cast<byte>(static_cast<unsigned char>(static_cast<unsigned int>(__lhs) << __shift));
+}
+
+template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr byte& operator>>=(byte& __lhs, _Integer __shift) noexcept {
+ return __lhs = __lhs >> __shift;
+}
+
+template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr byte operator>>(byte __lhs, _Integer __shift) noexcept {
+ return static_cast<byte>(static_cast<unsigned char>(static_cast<unsigned int>(__lhs) >> __shift));
+}
+
+template <class _Integer, __enable_if_t<is_integral<_Integer>::value, int> = 0>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Integer to_integer(byte __b) noexcept {
+ return static_cast<_Integer>(__b);
+}
+
+} // namespace std
+
+#endif
+
+#endif // _LIBCPP_CSTDDEF
diff --git a/libcxx/include/__cxx03/cstdint b/libcxx/include/__cxx03/cstdint
new file mode 100644
index 00000000000000..8c4782859426dd
--- /dev/null
+++ b/libcxx/include/__cxx03/cstdint
@@ -0,0 +1,199 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSTDINT
+#define _LIBCPP_CSTDINT
+
+/*
+ cstdint synopsis
+
+Macros:
+
+ INT8_MIN
+ INT16_MIN
+ INT32_MIN
+ INT64_MIN
+
+ INT8_MAX
+ INT16_MAX
+ INT32_MAX
+ INT64_MAX
+
+ UINT8_MAX
+ UINT16_MAX
+ UINT32_MAX
+ UINT64_MAX
+
+ INT_LEAST8_MIN
+ INT_LEAST16_MIN
+ INT_LEAST32_MIN
+ INT_LEAST64_MIN
+
+ INT_LEAST8_MAX
+ INT_LEAST16_MAX
+ INT_LEAST32_MAX
+ INT_LEAST64_MAX
+
+ UINT_LEAST8_MAX
+ UINT_LEAST16_MAX
+ UINT_LEAST32_MAX
+ UINT_LEAST64_MAX
+
+ INT_FAST8_MIN
+ INT_FAST16_MIN
+ INT_FAST32_MIN
+ INT_FAST64_MIN
+
+ INT_FAST8_MAX
+ INT_FAST16_MAX
+ INT_FAST32_MAX
+ INT_FAST64_MAX
+
+ UINT_FAST8_MAX
+ UINT_FAST16_MAX
+ UINT_FAST32_MAX
+ UINT_FAST64_MAX
+
+ INTPTR_MIN
+ INTPTR_MAX
+ UINTPTR_MAX
+
+ INTMAX_MIN
+ INTMAX_MAX
+
+ UINTMAX_MAX
+
+ PTRDIFF_MIN
+ PTRDIFF_MAX
+
+ SIG_ATOMIC_MIN
+ SIG_ATOMIC_MAX
+
+ SIZE_MAX
+
+ WCHAR_MIN
+ WCHAR_MAX
+
+ WINT_MIN
+ WINT_MAX
+
+ INT8_C(value)
+ INT16_C(value)
+ INT32_C(value)
+ INT64_C(value)
+
+ UINT8_C(value)
+ UINT16_C(value)
+ UINT32_C(value)
+ UINT64_C(value)
+
+ INTMAX_C(value)
+ UINTMAX_C(value)
+
+namespace std
+{
+
+Types:
+
+ int8_t
+ int16_t
+ int32_t
+ int64_t
+
+ uint8_t
+ uint16_t
+ uint32_t
+ uint64_t
+
+ int_least8_t
+ int_least16_t
+ int_least32_t
+ int_least64_t
+
+ uint_least8_t
+ uint_least16_t
+ uint_least32_t
+ uint_least64_t
+
+ int_fast8_t
+ int_fast16_t
+ int_fast32_t
+ int_fast64_t
+
+ uint_fast8_t
+ uint_fast16_t
+ uint_fast32_t
+ uint_fast64_t
+
+ intptr_t
+ uintptr_t
+
+ intmax_t
+ uintmax_t
+
+} // std
+*/
+
+#include <__config>
+
+#include <stdint.h>
+
+#ifndef _LIBCPP_STDINT_H
+# error <cstdint> tried including <stdint.h> but didn't find libc++'s <stdint.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::int8_t _LIBCPP_USING_IF_EXISTS;
+using ::int16_t _LIBCPP_USING_IF_EXISTS;
+using ::int32_t _LIBCPP_USING_IF_EXISTS;
+using ::int64_t _LIBCPP_USING_IF_EXISTS;
+
+using ::uint8_t _LIBCPP_USING_IF_EXISTS;
+using ::uint16_t _LIBCPP_USING_IF_EXISTS;
+using ::uint32_t _LIBCPP_USING_IF_EXISTS;
+using ::uint64_t _LIBCPP_USING_IF_EXISTS;
+
+using ::int_least8_t _LIBCPP_USING_IF_EXISTS;
+using ::int_least16_t _LIBCPP_USING_IF_EXISTS;
+using ::int_least32_t _LIBCPP_USING_IF_EXISTS;
+using ::int_least64_t _LIBCPP_USING_IF_EXISTS;
+
+using ::uint_least8_t _LIBCPP_USING_IF_EXISTS;
+using ::uint_least16_t _LIBCPP_USING_IF_EXISTS;
+using ::uint_least32_t _LIBCPP_USING_IF_EXISTS;
+using ::uint_least64_t _LIBCPP_USING_IF_EXISTS;
+
+using ::int_fast8_t _LIBCPP_USING_IF_EXISTS;
+using ::int_fast16_t _LIBCPP_USING_IF_EXISTS;
+using ::int_fast32_t _LIBCPP_USING_IF_EXISTS;
+using ::int_fast64_t _LIBCPP_USING_IF_EXISTS;
+
+using ::uint_fast8_t _LIBCPP_USING_IF_EXISTS;
+using ::uint_fast16_t _LIBCPP_USING_IF_EXISTS;
+using ::uint_fast32_t _LIBCPP_USING_IF_EXISTS;
+using ::uint_fast64_t _LIBCPP_USING_IF_EXISTS;
+
+using ::intptr_t _LIBCPP_USING_IF_EXISTS;
+using ::uintptr_t _LIBCPP_USING_IF_EXISTS;
+
+using ::intmax_t _LIBCPP_USING_IF_EXISTS;
+using ::uintmax_t _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CSTDINT
diff --git a/libcxx/include/__cxx03/cstdio b/libcxx/include/__cxx03/cstdio
new file mode 100644
index 00000000000000..7f94371081f8b1
--- /dev/null
+++ b/libcxx/include/__cxx03/cstdio
@@ -0,0 +1,174 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSTDIO
+#define _LIBCPP_CSTDIO
+
+/*
+ cstdio synopsis
+
+Macros:
+
+ BUFSIZ
+ EOF
+ FILENAME_MAX
+ FOPEN_MAX
+ L_tmpnam
+ NULL
+ SEEK_CUR
+ SEEK_END
+ SEEK_SET
+ TMP_MAX
+ _IOFBF
+ _IOLBF
+ _IONBF
+ stderr
+ stdin
+ stdout
+
+namespace std
+{
+
+Types:
+
+FILE
+fpos_t
+size_t
+
+int remove(const char* filename);
+int rename(const char* old, const char* new);
+FILE* tmpfile(void);
+char* tmpnam(char* s);
+int fclose(FILE* stream);
+int fflush(FILE* stream);
+FILE* fopen(const char* restrict filename, const char* restrict mode);
+FILE* freopen(const char* restrict filename, const char * restrict mode,
+ FILE * restrict stream);
+void setbuf(FILE* restrict stream, char* restrict buf);
+int setvbuf(FILE* restrict stream, char* restrict buf, int mode, size_t size);
+int fprintf(FILE* restrict stream, const char* restrict format, ...);
+int fscanf(FILE* restrict stream, const char * restrict format, ...);
+int printf(const char* restrict format, ...);
+int scanf(const char* restrict format, ...);
+int snprintf(char* restrict s, size_t n, const char* restrict format, ...); // C99
+int sprintf(char* restrict s, const char* restrict format, ...);
+int sscanf(const char* restrict s, const char* restrict format, ...);
+int vfprintf(FILE* restrict stream, const char* restrict format, va_list arg);
+int vfscanf(FILE* restrict stream, const char* restrict format, va_list arg); // C99
+int vprintf(const char* restrict format, va_list arg);
+int vscanf(const char* restrict format, va_list arg); // C99
+int vsnprintf(char* restrict s, size_t n, const char* restrict format, // C99
+ va_list arg);
+int vsprintf(char* restrict s, const char* restrict format, va_list arg);
+int vsscanf(const char* restrict s, const char* restrict format, va_list arg); // C99
+int fgetc(FILE* stream);
+char* fgets(char* restrict s, int n, FILE* restrict stream);
+int fputc(int c, FILE* stream);
+int fputs(const char* restrict s, FILE* restrict stream);
+int getc(FILE* stream);
+int getchar(void);
+char* gets(char* s); // removed in C++14
+int putc(int c, FILE* stream);
+int putchar(int c);
+int puts(const char* s);
+int ungetc(int c, FILE* stream);
+size_t fread(void* restrict ptr, size_t size, size_t nmemb,
+ FILE* restrict stream);
+size_t fwrite(const void* restrict ptr, size_t size, size_t nmemb,
+ FILE* restrict stream);
+int fgetpos(FILE* restrict stream, fpos_t* restrict pos);
+int fseek(FILE* stream, long offset, int whence);
+int fsetpos(FILE*stream, const fpos_t* pos);
+long ftell(FILE* stream);
+void rewind(FILE* stream);
+void clearerr(FILE* stream);
+int feof(FILE* stream);
+int ferror(FILE* stream);
+void perror(const char* s);
+
+} // std
+*/
+
+#include <__config>
+
+#include <stdio.h>
+
+#ifndef _LIBCPP_STDIO_H
+# error <cstdio> tried including <stdio.h> but didn't find libc++'s <stdio.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::FILE _LIBCPP_USING_IF_EXISTS;
+using ::fpos_t _LIBCPP_USING_IF_EXISTS;
+using ::size_t _LIBCPP_USING_IF_EXISTS;
+
+using ::fclose _LIBCPP_USING_IF_EXISTS;
+using ::fflush _LIBCPP_USING_IF_EXISTS;
+using ::setbuf _LIBCPP_USING_IF_EXISTS;
+using ::setvbuf _LIBCPP_USING_IF_EXISTS;
+using ::fprintf _LIBCPP_USING_IF_EXISTS;
+using ::fscanf _LIBCPP_USING_IF_EXISTS;
+using ::snprintf _LIBCPP_USING_IF_EXISTS;
+using ::sprintf _LIBCPP_USING_IF_EXISTS;
+using ::sscanf _LIBCPP_USING_IF_EXISTS;
+using ::vfprintf _LIBCPP_USING_IF_EXISTS;
+using ::vfscanf _LIBCPP_USING_IF_EXISTS;
+using ::vsscanf _LIBCPP_USING_IF_EXISTS;
+using ::vsnprintf _LIBCPP_USING_IF_EXISTS;
+using ::vsprintf _LIBCPP_USING_IF_EXISTS;
+using ::fgetc _LIBCPP_USING_IF_EXISTS;
+using ::fgets _LIBCPP_USING_IF_EXISTS;
+using ::fputc _LIBCPP_USING_IF_EXISTS;
+using ::fputs _LIBCPP_USING_IF_EXISTS;
+using ::getc _LIBCPP_USING_IF_EXISTS;
+using ::putc _LIBCPP_USING_IF_EXISTS;
+using ::ungetc _LIBCPP_USING_IF_EXISTS;
+using ::fread _LIBCPP_USING_IF_EXISTS;
+using ::fwrite _LIBCPP_USING_IF_EXISTS;
+using ::fgetpos _LIBCPP_USING_IF_EXISTS;
+using ::fseek _LIBCPP_USING_IF_EXISTS;
+using ::fsetpos _LIBCPP_USING_IF_EXISTS;
+using ::ftell _LIBCPP_USING_IF_EXISTS;
+using ::rewind _LIBCPP_USING_IF_EXISTS;
+using ::clearerr _LIBCPP_USING_IF_EXISTS;
+using ::feof _LIBCPP_USING_IF_EXISTS;
+using ::ferror _LIBCPP_USING_IF_EXISTS;
+using ::perror _LIBCPP_USING_IF_EXISTS;
+
+using ::fopen _LIBCPP_USING_IF_EXISTS;
+using ::freopen _LIBCPP_USING_IF_EXISTS;
+using ::remove _LIBCPP_USING_IF_EXISTS;
+using ::rename _LIBCPP_USING_IF_EXISTS;
+using ::tmpfile _LIBCPP_USING_IF_EXISTS;
+using ::tmpnam _LIBCPP_USING_IF_EXISTS;
+
+using ::getchar _LIBCPP_USING_IF_EXISTS;
+#if _LIBCPP_STD_VER <= 11
+using ::gets _LIBCPP_USING_IF_EXISTS;
+#endif
+using ::scanf _LIBCPP_USING_IF_EXISTS;
+using ::vscanf _LIBCPP_USING_IF_EXISTS;
+
+using ::printf _LIBCPP_USING_IF_EXISTS;
+using ::putchar _LIBCPP_USING_IF_EXISTS;
+using ::puts _LIBCPP_USING_IF_EXISTS;
+using ::vprintf _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CSTDIO
diff --git a/libcxx/include/__cxx03/cstdlib b/libcxx/include/__cxx03/cstdlib
new file mode 100644
index 00000000000000..c817fd8f4accda
--- /dev/null
+++ b/libcxx/include/__cxx03/cstdlib
@@ -0,0 +1,154 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSTDLIB
+#define _LIBCPP_CSTDLIB
+
+/*
+ cstdlib synopsis
+
+Macros:
+
+ EXIT_FAILURE
+ EXIT_SUCCESS
+ MB_CUR_MAX
+ NULL
+ RAND_MAX
+
+namespace std
+{
+
+Types:
+
+ size_t
+ div_t
+ ldiv_t
+ lldiv_t // C99
+
+double atof (const char* nptr);
+int atoi (const char* nptr);
+long atol (const char* nptr);
+long long atoll(const char* nptr); // C99
+double strtod (const char* restrict nptr, char** restrict endptr);
+float strtof (const char* restrict nptr, char** restrict endptr); // C99
+long double strtold (const char* restrict nptr, char** restrict endptr); // C99
+long strtol (const char* restrict nptr, char** restrict endptr, int base);
+long long strtoll (const char* restrict nptr, char** restrict endptr, int base); // C99
+unsigned long strtoul (const char* restrict nptr, char** restrict endptr, int base);
+unsigned long long strtoull(const char* restrict nptr, char** restrict endptr, int base); // C99
+int rand(void);
+void srand(unsigned int seed);
+void* calloc(size_t nmemb, size_t size);
+void free(void* ptr);
+void* malloc(size_t size);
+void* realloc(void* ptr, size_t size);
+void abort(void);
+int atexit(void (*func)(void));
+void exit(int status);
+void _Exit(int status);
+char* getenv(const char* name);
+int system(const char* string);
+void* bsearch(const void* key, const void* base, size_t nmemb, size_t size,
+ int (*compar)(const void *, const void *));
+void qsort(void* base, size_t nmemb, size_t size,
+ int (*compar)(const void *, const void *));
+int abs( int j);
+long abs( long j);
+long long abs(long long j); // C++0X
+long labs( long j);
+long long llabs(long long j); // C99
+div_t div( int numer, int denom);
+ldiv_t div( long numer, long denom);
+lldiv_t div(long long numer, long long denom); // C++0X
+ldiv_t ldiv( long numer, long denom);
+lldiv_t lldiv(long long numer, long long denom); // C99
+int mblen(const char* s, size_t n);
+int mbtowc(wchar_t* restrict pwc, const char* restrict s, size_t n);
+int wctomb(char* s, wchar_t wchar);
+size_t mbstowcs(wchar_t* restrict pwcs, const char* restrict s, size_t n);
+size_t wcstombs(char* restrict s, const wchar_t* restrict pwcs, size_t n);
+int at_quick_exit(void (*func)(void)) // C++11
+void quick_exit(int status); // C++11
+void *aligned_alloc(size_t alignment, size_t size); // C11
+
+} // std
+
+*/
+
+#include <__config>
+
+#include <stdlib.h>
+
+#ifndef _LIBCPP_STDLIB_H
+# error <cstdlib> tried including <stdlib.h> but didn't find libc++'s <stdlib.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::size_t _LIBCPP_USING_IF_EXISTS;
+using ::div_t _LIBCPP_USING_IF_EXISTS;
+using ::ldiv_t _LIBCPP_USING_IF_EXISTS;
+using ::lldiv_t _LIBCPP_USING_IF_EXISTS;
+using ::atof _LIBCPP_USING_IF_EXISTS;
+using ::atoi _LIBCPP_USING_IF_EXISTS;
+using ::atol _LIBCPP_USING_IF_EXISTS;
+using ::atoll _LIBCPP_USING_IF_EXISTS;
+using ::strtod _LIBCPP_USING_IF_EXISTS;
+using ::strtof _LIBCPP_USING_IF_EXISTS;
+using ::strtold _LIBCPP_USING_IF_EXISTS;
+using ::strtol _LIBCPP_USING_IF_EXISTS;
+using ::strtoll _LIBCPP_USING_IF_EXISTS;
+using ::strtoul _LIBCPP_USING_IF_EXISTS;
+using ::strtoull _LIBCPP_USING_IF_EXISTS;
+using ::rand _LIBCPP_USING_IF_EXISTS;
+using ::srand _LIBCPP_USING_IF_EXISTS;
+using ::calloc _LIBCPP_USING_IF_EXISTS;
+using ::free _LIBCPP_USING_IF_EXISTS;
+using ::malloc _LIBCPP_USING_IF_EXISTS;
+using ::realloc _LIBCPP_USING_IF_EXISTS;
+using ::abort _LIBCPP_USING_IF_EXISTS;
+using ::atexit _LIBCPP_USING_IF_EXISTS;
+using ::exit _LIBCPP_USING_IF_EXISTS;
+using ::_Exit _LIBCPP_USING_IF_EXISTS;
+using ::getenv _LIBCPP_USING_IF_EXISTS;
+using ::system _LIBCPP_USING_IF_EXISTS;
+using ::bsearch _LIBCPP_USING_IF_EXISTS;
+using ::qsort _LIBCPP_USING_IF_EXISTS;
+using ::abs _LIBCPP_USING_IF_EXISTS;
+using ::labs _LIBCPP_USING_IF_EXISTS;
+using ::llabs _LIBCPP_USING_IF_EXISTS;
+using ::div _LIBCPP_USING_IF_EXISTS;
+using ::ldiv _LIBCPP_USING_IF_EXISTS;
+using ::lldiv _LIBCPP_USING_IF_EXISTS;
+using ::mblen _LIBCPP_USING_IF_EXISTS;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using ::mbtowc _LIBCPP_USING_IF_EXISTS;
+using ::wctomb _LIBCPP_USING_IF_EXISTS;
+using ::mbstowcs _LIBCPP_USING_IF_EXISTS;
+using ::wcstombs _LIBCPP_USING_IF_EXISTS;
+#endif
+#if !defined(_LIBCPP_CXX03_LANG)
+using ::at_quick_exit _LIBCPP_USING_IF_EXISTS;
+using ::quick_exit _LIBCPP_USING_IF_EXISTS;
+#endif
+#if _LIBCPP_STD_VER >= 17
+using ::aligned_alloc _LIBCPP_USING_IF_EXISTS;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CSTDLIB
diff --git a/libcxx/include/__cxx03/cstring b/libcxx/include/__cxx03/cstring
new file mode 100644
index 00000000000000..c2c92b02e73cc1
--- /dev/null
+++ b/libcxx/include/__cxx03/cstring
@@ -0,0 +1,104 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CSTRING
+#define _LIBCPP_CSTRING
+
+/*
+ cstring synopsis
+
+Macros:
+
+ NULL
+
+namespace std
+{
+
+Types:
+
+ size_t
+
+void* memcpy(void* restrict s1, const void* restrict s2, size_t n);
+void* memmove(void* s1, const void* s2, size_t n);
+char* strcpy (char* restrict s1, const char* restrict s2);
+char* strncpy(char* restrict s1, const char* restrict s2, size_t n);
+char* strcat (char* restrict s1, const char* restrict s2);
+char* strncat(char* restrict s1, const char* restrict s2, size_t n);
+int memcmp(const void* s1, const void* s2, size_t n);
+int strcmp (const char* s1, const char* s2);
+int strncmp(const char* s1, const char* s2, size_t n);
+int strcoll(const char* s1, const char* s2);
+size_t strxfrm(char* restrict s1, const char* restrict s2, size_t n);
+const void* memchr(const void* s, int c, size_t n);
+ void* memchr( void* s, int c, size_t n);
+const char* strchr(const char* s, int c);
+ char* strchr( char* s, int c);
+size_t strcspn(const char* s1, const char* s2);
+const char* strpbrk(const char* s1, const char* s2);
+ char* strpbrk( char* s1, const char* s2);
+const char* strrchr(const char* s, int c);
+ char* strrchr( char* s, int c);
+size_t strspn(const char* s1, const char* s2);
+const char* strstr(const char* s1, const char* s2);
+ char* strstr( char* s1, const char* s2);
+char* strtok(char* restrict s1, const char* restrict s2);
+void* memset(void* s, int c, size_t n);
+char* strerror(int errnum);
+size_t strlen(const char* s);
+
+} // std
+
+*/
+
+#include <__config>
+#include <__type_traits/is_constant_evaluated.h>
+
+#include <string.h>
+
+#ifndef _LIBCPP_STRING_H
+# error <cstring> tried including <string.h> but didn't find libc++'s <string.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::size_t _LIBCPP_USING_IF_EXISTS;
+using ::memcpy _LIBCPP_USING_IF_EXISTS;
+using ::memmove _LIBCPP_USING_IF_EXISTS;
+using ::strcpy _LIBCPP_USING_IF_EXISTS;
+using ::strncpy _LIBCPP_USING_IF_EXISTS;
+using ::strcat _LIBCPP_USING_IF_EXISTS;
+using ::strncat _LIBCPP_USING_IF_EXISTS;
+using ::memcmp _LIBCPP_USING_IF_EXISTS;
+using ::strcmp _LIBCPP_USING_IF_EXISTS;
+using ::strncmp _LIBCPP_USING_IF_EXISTS;
+using ::strcoll _LIBCPP_USING_IF_EXISTS;
+using ::strxfrm _LIBCPP_USING_IF_EXISTS;
+using ::memchr _LIBCPP_USING_IF_EXISTS;
+using ::strchr _LIBCPP_USING_IF_EXISTS;
+using ::strcspn _LIBCPP_USING_IF_EXISTS;
+using ::strpbrk _LIBCPP_USING_IF_EXISTS;
+using ::strrchr _LIBCPP_USING_IF_EXISTS;
+using ::strspn _LIBCPP_USING_IF_EXISTS;
+using ::strstr _LIBCPP_USING_IF_EXISTS;
+using ::strtok _LIBCPP_USING_IF_EXISTS;
+using ::memset _LIBCPP_USING_IF_EXISTS;
+using ::strerror _LIBCPP_USING_IF_EXISTS;
+using ::strlen _LIBCPP_USING_IF_EXISTS;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CSTRING
diff --git a/libcxx/include/__cxx03/ctgmath b/libcxx/include/__cxx03/ctgmath
new file mode 100644
index 00000000000000..6237979be4906c
--- /dev/null
+++ b/libcxx/include/__cxx03/ctgmath
@@ -0,0 +1,28 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CTGMATH
+#define _LIBCPP_CTGMATH
+
+/*
+ ctgmath synopsis
+
+#include <ccomplex>
+#include <cmath>
+
+*/
+
+#include <ccomplex>
+#include <cmath>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#endif // _LIBCPP_CTGMATH
diff --git a/libcxx/include/__cxx03/ctime b/libcxx/include/__cxx03/ctime
new file mode 100644
index 00000000000000..f47b49a43e23ef
--- /dev/null
+++ b/libcxx/include/__cxx03/ctime
@@ -0,0 +1,86 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CTIME
+#define _LIBCPP_CTIME
+
+/*
+ ctime synopsis
+
+Macros:
+
+ NULL
+ CLOCKS_PER_SEC
+ TIME_UTC // C++17
+
+namespace std
+{
+
+Types:
+
+ clock_t
+ size_t
+ time_t
+ tm
+ timespec // C++17
+
+clock_t clock();
+double difftime(time_t time1, time_t time0);
+time_t mktime(tm* timeptr);
+time_t time(time_t* timer);
+char* asctime(const tm* timeptr);
+char* ctime(const time_t* timer);
+tm* gmtime(const time_t* timer);
+tm* localtime(const time_t* timer);
+size_t strftime(char* restrict s, size_t maxsize, const char* restrict format,
+ const tm* restrict timeptr);
+int timespec_get( struct timespec *ts, int base); // C++17
+} // std
+
+*/
+
+#include <__config>
+
+// <time.h> is not provided by libc++
+#if __has_include(<time.h>)
+# include <time.h>
+# ifdef _LIBCPP_TIME_H
+# error "If libc++ starts defining <time.h>, the __has_include check should move to libc++'s <time.h>"
+# endif
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::clock_t _LIBCPP_USING_IF_EXISTS;
+using ::size_t _LIBCPP_USING_IF_EXISTS;
+using ::time_t _LIBCPP_USING_IF_EXISTS;
+using ::tm _LIBCPP_USING_IF_EXISTS;
+#if _LIBCPP_STD_VER >= 17
+using ::timespec _LIBCPP_USING_IF_EXISTS;
+#endif
+using ::clock _LIBCPP_USING_IF_EXISTS;
+using ::difftime _LIBCPP_USING_IF_EXISTS;
+using ::mktime _LIBCPP_USING_IF_EXISTS;
+using ::time _LIBCPP_USING_IF_EXISTS;
+using ::asctime _LIBCPP_USING_IF_EXISTS;
+using ::ctime _LIBCPP_USING_IF_EXISTS;
+using ::gmtime _LIBCPP_USING_IF_EXISTS;
+using ::localtime _LIBCPP_USING_IF_EXISTS;
+using ::strftime _LIBCPP_USING_IF_EXISTS;
+#if _LIBCPP_STD_VER >= 17
+using ::timespec_get _LIBCPP_USING_IF_EXISTS;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CTIME
diff --git a/libcxx/include/__cxx03/ctype.h b/libcxx/include/__cxx03/ctype.h
new file mode 100644
index 00000000000000..448e4410c554f1
--- /dev/null
+++ b/libcxx/include/__cxx03/ctype.h
@@ -0,0 +1,61 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CTYPE_H
+#define _LIBCPP_CTYPE_H
+
+/*
+ ctype.h synopsis
+
+int isalnum(int c);
+int isalpha(int c);
+int isblank(int c); // C99
+int iscntrl(int c);
+int isdigit(int c);
+int isgraph(int c);
+int islower(int c);
+int isprint(int c);
+int ispunct(int c);
+int isspace(int c);
+int isupper(int c);
+int isxdigit(int c);
+int tolower(int c);
+int toupper(int c);
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if __has_include_next(<ctype.h>)
+# include_next <ctype.h>
+#endif
+
+#ifdef __cplusplus
+
+# undef isalnum
+# undef isalpha
+# undef isblank
+# undef iscntrl
+# undef isdigit
+# undef isgraph
+# undef islower
+# undef isprint
+# undef ispunct
+# undef isspace
+# undef isupper
+# undef isxdigit
+# undef tolower
+# undef toupper
+
+#endif
+
+#endif // _LIBCPP_CTYPE_H
diff --git a/libcxx/include/__cxx03/cuchar b/libcxx/include/__cxx03/cuchar
new file mode 100644
index 00000000000000..f0015be275367d
--- /dev/null
+++ b/libcxx/include/__cxx03/cuchar
@@ -0,0 +1,75 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CUCHAR
+#define _LIBCPP_CUCHAR
+
+/*
+ cuchar synopsis // since C++11
+
+Macros:
+
+ __STDC_UTF_16__
+ __STDC_UTF_32__
+
+namespace std {
+
+Types:
+
+ mbstate_t
+ size_t
+
+size_t mbrtoc8(char8_t* pc8, const char* s, size_t n, mbstate_t* ps); // since C++20
+size_t c8rtomb(char* s, char8_t c8, mbstate_t* ps); // since C++20
+size_t mbrtoc16(char16_t* pc16, const char* s, size_t n, mbstate_t* ps);
+size_t c16rtomb(char* s, char16_t c16, mbstate_t* ps);
+size_t mbrtoc32(char32_t* pc32, const char* s, size_t n, mbstate_t* ps);
+size_t c32rtomb(char* s, char32_t c32, mbstate_t* ps);
+
+} // std
+
+*/
+
+#include <__config>
+
+#include <uchar.h>
+
+#ifndef _LIBCPP_UCHAR_H
+# error <cuchar> tried including <uchar.h> but didn't find libc++'s <uchar.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if !defined(_LIBCPP_CXX03_LANG)
+
+using ::mbstate_t _LIBCPP_USING_IF_EXISTS;
+using ::size_t _LIBCPP_USING_IF_EXISTS;
+
+# if !defined(_LIBCPP_HAS_NO_C8RTOMB_MBRTOC8)
+using ::mbrtoc8 _LIBCPP_USING_IF_EXISTS;
+using ::c8rtomb _LIBCPP_USING_IF_EXISTS;
+# endif
+using ::mbrtoc16 _LIBCPP_USING_IF_EXISTS;
+using ::c16rtomb _LIBCPP_USING_IF_EXISTS;
+using ::mbrtoc32 _LIBCPP_USING_IF_EXISTS;
+using ::c32rtomb _LIBCPP_USING_IF_EXISTS;
+
+#endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CUCHAR
diff --git a/libcxx/include/__cxx03/cwchar b/libcxx/include/__cxx03/cwchar
new file mode 100644
index 00000000000000..08cfac58c846ac
--- /dev/null
+++ b/libcxx/include/__cxx03/cwchar
@@ -0,0 +1,261 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CWCHAR
+#define _LIBCPP_CWCHAR
+
+/*
+ cwchar synopsis
+
+Macros:
+
+ NULL
+ WCHAR_MAX
+ WCHAR_MIN
+ WEOF
+
+namespace std
+{
+
+Types:
+
+ mbstate_t
+ size_t
+ tm
+ wint_t
+
+int fwprintf(FILE* restrict stream, const wchar_t* restrict format, ...);
+int fwscanf(FILE* restrict stream, const wchar_t* restrict format, ...);
+int swprintf(wchar_t* restrict s, size_t n, const wchar_t* restrict format, ...);
+int swscanf(const wchar_t* restrict s, const wchar_t* restrict format, ...);
+int vfwprintf(FILE* restrict stream, const wchar_t* restrict format, va_list arg);
+int vfwscanf(FILE* restrict stream, const wchar_t* restrict format, va_list arg); // C99
+int vswprintf(wchar_t* restrict s, size_t n, const wchar_t* restrict format, va_list arg);
+int vswscanf(const wchar_t* restrict s, const wchar_t* restrict format, va_list arg); // C99
+int vwprintf(const wchar_t* restrict format, va_list arg);
+int vwscanf(const wchar_t* restrict format, va_list arg); // C99
+int wprintf(const wchar_t* restrict format, ...);
+int wscanf(const wchar_t* restrict format, ...);
+wint_t fgetwc(FILE* stream);
+wchar_t* fgetws(wchar_t* restrict s, int n, FILE* restrict stream);
+wint_t fputwc(wchar_t c, FILE* stream);
+int fputws(const wchar_t* restrict s, FILE* restrict stream);
+int fwide(FILE* stream, int mode);
+wint_t getwc(FILE* stream);
+wint_t getwchar();
+wint_t putwc(wchar_t c, FILE* stream);
+wint_t putwchar(wchar_t c);
+wint_t ungetwc(wint_t c, FILE* stream);
+double wcstod(const wchar_t* restrict nptr, wchar_t** restrict endptr);
+float wcstof(const wchar_t* restrict nptr, wchar_t** restrict endptr); // C99
+long double wcstold(const wchar_t* restrict nptr, wchar_t** restrict endptr); // C99
+long wcstol(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base);
+long long wcstoll(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base); // C99
+unsigned long wcstoul(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base);
+unsigned long long wcstoull(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base); // C99
+wchar_t* wcscpy(wchar_t* restrict s1, const wchar_t* restrict s2);
+wchar_t* wcsncpy(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+wchar_t* wcscat(wchar_t* restrict s1, const wchar_t* restrict s2);
+wchar_t* wcsncat(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+int wcscmp(const wchar_t* s1, const wchar_t* s2);
+int wcscoll(const wchar_t* s1, const wchar_t* s2);
+int wcsncmp(const wchar_t* s1, const wchar_t* s2, size_t n);
+size_t wcsxfrm(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+const wchar_t* wcschr(const wchar_t* s, wchar_t c);
+ wchar_t* wcschr( wchar_t* s, wchar_t c);
+size_t wcscspn(const wchar_t* s1, const wchar_t* s2);
+size_t wcslen(const wchar_t* s);
+const wchar_t* wcspbrk(const wchar_t* s1, const wchar_t* s2);
+ wchar_t* wcspbrk( wchar_t* s1, const wchar_t* s2);
+const wchar_t* wcsrchr(const wchar_t* s, wchar_t c);
+ wchar_t* wcsrchr( wchar_t* s, wchar_t c);
+size_t wcsspn(const wchar_t* s1, const wchar_t* s2);
+const wchar_t* wcsstr(const wchar_t* s1, const wchar_t* s2);
+ wchar_t* wcsstr( wchar_t* s1, const wchar_t* s2);
+wchar_t* wcstok(wchar_t* restrict s1, const wchar_t* restrict s2, wchar_t** restrict ptr);
+const wchar_t* wmemchr(const wchar_t* s, wchar_t c, size_t n);
+ wchar_t* wmemchr( wchar_t* s, wchar_t c, size_t n);
+int wmemcmp(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+wchar_t* wmemcpy(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+wchar_t* wmemmove(wchar_t* s1, const wchar_t* s2, size_t n);
+wchar_t* wmemset(wchar_t* s, wchar_t c, size_t n);
+size_t wcsftime(wchar_t* restrict s, size_t maxsize, const wchar_t* restrict format,
+ const tm* restrict timeptr);
+wint_t btowc(int c);
+int wctob(wint_t c);
+int mbsinit(const mbstate_t* ps);
+size_t mbrlen(const char* restrict s, size_t n, mbstate_t* restrict ps);
+size_t mbrtowc(wchar_t* restrict pwc, const char* restrict s, size_t n, mbstate_t* restrict ps);
+size_t wcrtomb(char* restrict s, wchar_t wc, mbstate_t* restrict ps);
+size_t mbsrtowcs(wchar_t* restrict dst, const char** restrict src, size_t len,
+ mbstate_t* restrict ps);
+size_t wcsrtombs(char* restrict dst, const wchar_t** restrict src, size_t len,
+ mbstate_t* restrict ps);
+
+} // std
+
+*/
+
+#include <__config>
+#include <__type_traits/copy_cv.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_equality_comparable.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cv.h>
+#include <cwctype>
+
+#include <wchar.h>
+
+#ifndef _LIBCPP_WCHAR_H
+# error <cwchar> tried including <wchar.h> but didn't find libc++'s <wchar.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+using ::mbstate_t _LIBCPP_USING_IF_EXISTS;
+using ::size_t _LIBCPP_USING_IF_EXISTS;
+using ::tm _LIBCPP_USING_IF_EXISTS;
+using ::wint_t _LIBCPP_USING_IF_EXISTS;
+using ::FILE _LIBCPP_USING_IF_EXISTS;
+using ::fwprintf _LIBCPP_USING_IF_EXISTS;
+using ::fwscanf _LIBCPP_USING_IF_EXISTS;
+using ::swprintf _LIBCPP_USING_IF_EXISTS;
+using ::vfwprintf _LIBCPP_USING_IF_EXISTS;
+using ::vswprintf _LIBCPP_USING_IF_EXISTS;
+using ::swscanf _LIBCPP_USING_IF_EXISTS;
+using ::vfwscanf _LIBCPP_USING_IF_EXISTS;
+using ::vswscanf _LIBCPP_USING_IF_EXISTS;
+using ::fgetwc _LIBCPP_USING_IF_EXISTS;
+using ::fgetws _LIBCPP_USING_IF_EXISTS;
+using ::fputwc _LIBCPP_USING_IF_EXISTS;
+using ::fputws _LIBCPP_USING_IF_EXISTS;
+using ::fwide _LIBCPP_USING_IF_EXISTS;
+using ::getwc _LIBCPP_USING_IF_EXISTS;
+using ::putwc _LIBCPP_USING_IF_EXISTS;
+using ::ungetwc _LIBCPP_USING_IF_EXISTS;
+using ::wcstod _LIBCPP_USING_IF_EXISTS;
+using ::wcstof _LIBCPP_USING_IF_EXISTS;
+using ::wcstold _LIBCPP_USING_IF_EXISTS;
+using ::wcstol _LIBCPP_USING_IF_EXISTS;
+using ::wcstoll _LIBCPP_USING_IF_EXISTS;
+using ::wcstoul _LIBCPP_USING_IF_EXISTS;
+using ::wcstoull _LIBCPP_USING_IF_EXISTS;
+using ::wcscpy _LIBCPP_USING_IF_EXISTS;
+using ::wcsncpy _LIBCPP_USING_IF_EXISTS;
+using ::wcscat _LIBCPP_USING_IF_EXISTS;
+using ::wcsncat _LIBCPP_USING_IF_EXISTS;
+using ::wcscmp _LIBCPP_USING_IF_EXISTS;
+using ::wcscoll _LIBCPP_USING_IF_EXISTS;
+using ::wcsncmp _LIBCPP_USING_IF_EXISTS;
+using ::wcsxfrm _LIBCPP_USING_IF_EXISTS;
+using ::wcschr _LIBCPP_USING_IF_EXISTS;
+using ::wcspbrk _LIBCPP_USING_IF_EXISTS;
+using ::wcsrchr _LIBCPP_USING_IF_EXISTS;
+using ::wcsstr _LIBCPP_USING_IF_EXISTS;
+using ::wmemchr _LIBCPP_USING_IF_EXISTS;
+using ::wcscspn _LIBCPP_USING_IF_EXISTS;
+using ::wcslen _LIBCPP_USING_IF_EXISTS;
+using ::wcsspn _LIBCPP_USING_IF_EXISTS;
+using ::wcstok _LIBCPP_USING_IF_EXISTS;
+using ::wmemcmp _LIBCPP_USING_IF_EXISTS;
+using ::wmemcpy _LIBCPP_USING_IF_EXISTS;
+using ::wmemmove _LIBCPP_USING_IF_EXISTS;
+using ::wmemset _LIBCPP_USING_IF_EXISTS;
+using ::wcsftime _LIBCPP_USING_IF_EXISTS;
+using ::btowc _LIBCPP_USING_IF_EXISTS;
+using ::wctob _LIBCPP_USING_IF_EXISTS;
+using ::mbsinit _LIBCPP_USING_IF_EXISTS;
+using ::mbrlen _LIBCPP_USING_IF_EXISTS;
+using ::mbrtowc _LIBCPP_USING_IF_EXISTS;
+using ::wcrtomb _LIBCPP_USING_IF_EXISTS;
+using ::mbsrtowcs _LIBCPP_USING_IF_EXISTS;
+using ::wcsrtombs _LIBCPP_USING_IF_EXISTS;
+
+using ::getwchar _LIBCPP_USING_IF_EXISTS;
+using ::vwscanf _LIBCPP_USING_IF_EXISTS;
+using ::wscanf _LIBCPP_USING_IF_EXISTS;
+
+using ::putwchar _LIBCPP_USING_IF_EXISTS;
+using ::vwprintf _LIBCPP_USING_IF_EXISTS;
+using ::wprintf _LIBCPP_USING_IF_EXISTS;
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 size_t __constexpr_wcslen(const wchar_t* __str) {
+#if __has_builtin(__builtin_wcslen)
+ return __builtin_wcslen(__str);
+#else
+ if (!__libcpp_is_constant_evaluated())
+ return std::wcslen(__str);
+
+ size_t __len = 0;
+ for (; *__str != L'\0'; ++__str)
+ ++__len;
+ return __len;
+#endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int
+__constexpr_wmemcmp(const wchar_t* __lhs, const wchar_t* __rhs, size_t __count) {
+#if __has_builtin(__builtin_wmemcmp)
+ return __builtin_wmemcmp(__lhs, __rhs, __count);
+#else
+ if (!__libcpp_is_constant_evaluated())
+ return std::wmemcmp(__lhs, __rhs, __count);
+
+ for (; __count; --__count, ++__lhs, ++__rhs) {
+ if (*__lhs < *__rhs)
+ return -1;
+ if (*__rhs < *__lhs)
+ return 1;
+ }
+ return 0;
+#endif
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp* __constexpr_wmemchr(_Tp* __str, _Up __value, size_t __count) {
+ static_assert(sizeof(_Tp) == sizeof(wchar_t)&& _LIBCPP_ALIGNOF(_Tp) >= _LIBCPP_ALIGNOF(wchar_t) &&
+ __libcpp_is_trivially_equality_comparable<_Tp, _Tp>::value,
+ "Calling wmemchr on non-trivially equality comparable types is unsafe.");
+
+#if __has_builtin(__builtin_wmemchr)
+ if (!__libcpp_is_constant_evaluated()) {
+ wchar_t __value_buffer = 0;
+ __builtin_memcpy(&__value_buffer, &__value, sizeof(wchar_t));
+ return reinterpret_cast<_Tp*>(
+ __builtin_wmemchr(reinterpret_cast<__copy_cv_t<_Tp, wchar_t>*>(__str), __value_buffer, __count));
+ }
+# if _LIBCPP_STD_VER >= 17
+ else if constexpr (is_same_v<remove_cv_t<_Tp>, wchar_t>)
+ return __builtin_wmemchr(__str, __value, __count);
+# endif
+#endif // __has_builtin(__builtin_wmemchr)
+
+ for (; __count; --__count) {
+ if (*__str == __value)
+ return __str;
+ ++__str;
+ }
+ return nullptr;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstddef>
+#endif
+
+#endif // _LIBCPP_CWCHAR
diff --git a/libcxx/include/__cxx03/cwctype b/libcxx/include/__cxx03/cwctype
new file mode 100644
index 00000000000000..04abfabef57933
--- /dev/null
+++ b/libcxx/include/__cxx03/cwctype
@@ -0,0 +1,97 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CWCTYPE
+#define _LIBCPP_CWCTYPE
+
+/*
+ cwctype synopsis
+
+Macros:
+
+ WEOF
+
+namespace std
+{
+
+Types:
+
+ wint_t
+ wctrans_t
+ wctype_t
+
+int iswalnum(wint_t wc);
+int iswalpha(wint_t wc);
+int iswblank(wint_t wc); // C99
+int iswcntrl(wint_t wc);
+int iswdigit(wint_t wc);
+int iswgraph(wint_t wc);
+int iswlower(wint_t wc);
+int iswprint(wint_t wc);
+int iswpunct(wint_t wc);
+int iswspace(wint_t wc);
+int iswupper(wint_t wc);
+int iswxdigit(wint_t wc);
+int iswctype(wint_t wc, wctype_t desc);
+wctype_t wctype(const char* property);
+wint_t towlower(wint_t wc);
+wint_t towupper(wint_t wc);
+wint_t towctrans(wint_t wc, wctrans_t desc);
+wctrans_t wctrans(const char* property);
+
+} // std
+
+*/
+
+#include <__config>
+#include <cctype>
+
+#include <wctype.h>
+
+#ifndef _LIBCPP_WCTYPE_H
+# error <cwctype> tried including <wctype.h> but didn't find libc++'s <wctype.h> header. \
+ This usually means that your header search paths are not configured properly. \
+ The header search paths should contain the C++ Standard Library headers before \
+ any C Standard Library, and you are probably using compiler flags that make that \
+ not be the case.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if defined(_LIBCPP_INCLUDED_C_LIBRARY_WCTYPE_H)
+using ::wint_t _LIBCPP_USING_IF_EXISTS;
+using ::wctrans_t _LIBCPP_USING_IF_EXISTS;
+using ::wctype_t _LIBCPP_USING_IF_EXISTS;
+using ::iswalnum _LIBCPP_USING_IF_EXISTS;
+using ::iswalpha _LIBCPP_USING_IF_EXISTS;
+using ::iswblank _LIBCPP_USING_IF_EXISTS;
+using ::iswcntrl _LIBCPP_USING_IF_EXISTS;
+using ::iswdigit _LIBCPP_USING_IF_EXISTS;
+using ::iswgraph _LIBCPP_USING_IF_EXISTS;
+using ::iswlower _LIBCPP_USING_IF_EXISTS;
+using ::iswprint _LIBCPP_USING_IF_EXISTS;
+using ::iswpunct _LIBCPP_USING_IF_EXISTS;
+using ::iswspace _LIBCPP_USING_IF_EXISTS;
+using ::iswupper _LIBCPP_USING_IF_EXISTS;
+using ::iswxdigit _LIBCPP_USING_IF_EXISTS;
+using ::iswctype _LIBCPP_USING_IF_EXISTS;
+using ::wctype _LIBCPP_USING_IF_EXISTS;
+using ::towlower _LIBCPP_USING_IF_EXISTS;
+using ::towupper _LIBCPP_USING_IF_EXISTS;
+using ::towctrans _LIBCPP_USING_IF_EXISTS;
+using ::wctrans _LIBCPP_USING_IF_EXISTS;
+#endif // _LIBCPP_INCLUDED_C_LIBRARY_WCTYPE_H
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_CWCTYPE
diff --git a/libcxx/include/__cxx03/deque b/libcxx/include/__cxx03/deque
new file mode 100644
index 00000000000000..e73135a8647b98
--- /dev/null
+++ b/libcxx/include/__cxx03/deque
@@ -0,0 +1,2621 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_DEQUE
+#define _LIBCPP_DEQUE
+
+/*
+ deque synopsis
+
+namespace std
+{
+
+template <class T, class Allocator = allocator<T> >
+class deque
+{
+public:
+ // types:
+ typedef T value_type;
+ typedef Allocator allocator_type;
+
+ typedef typename allocator_type::reference reference;
+ typedef typename allocator_type::const_reference const_reference;
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef typename allocator_type::size_type size_type;
+ typedef typename allocator_type::difference_type difference_type;
+
+ typedef typename allocator_type::pointer pointer;
+ typedef typename allocator_type::const_pointer const_pointer;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+ // construct/copy/destroy:
+ deque() noexcept(is_nothrow_default_constructible<allocator_type>::value);
+ explicit deque(const allocator_type& a);
+ explicit deque(size_type n);
+ explicit deque(size_type n, const allocator_type& a); // C++14
+ deque(size_type n, const value_type& v);
+ deque(size_type n, const value_type& v, const allocator_type& a);
+ template <class InputIterator>
+ deque(InputIterator f, InputIterator l);
+ template <class InputIterator>
+ deque(InputIterator f, InputIterator l, const allocator_type& a);
+ template<container-compatible-range<T> R>
+ deque(from_range_t, R&& rg, const Allocator& = Allocator()); // C++23
+ deque(const deque& c);
+ deque(deque&& c)
+ noexcept(is_nothrow_move_constructible<allocator_type>::value);
+ deque(initializer_list<value_type> il, const Allocator& a = allocator_type());
+ deque(const deque& c, const allocator_type& a);
+ deque(deque&& c, const allocator_type& a);
+ ~deque();
+
+ deque& operator=(const deque& c);
+ deque& operator=(deque&& c)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value);
+ deque& operator=(initializer_list<value_type> il);
+
+ template <class InputIterator>
+ void assign(InputIterator f, InputIterator l);
+ template<container-compatible-range<T> R>
+ void assign_range(R&& rg); // C++23
+ void assign(size_type n, const value_type& v);
+ void assign(initializer_list<value_type> il);
+
+ allocator_type get_allocator() const noexcept;
+
+ // iterators:
+
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+
+ reverse_iterator rbegin() noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ reverse_iterator rend() noexcept;
+ const_reverse_iterator rend() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ // capacity:
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+ void resize(size_type n);
+ void resize(size_type n, const value_type& v);
+ void shrink_to_fit();
+ bool empty() const noexcept;
+
+ // element access:
+ reference operator[](size_type i);
+ const_reference operator[](size_type i) const;
+ reference at(size_type i);
+ const_reference at(size_type i) const;
+ reference front();
+ const_reference front() const;
+ reference back();
+ const_reference back() const;
+
+ // modifiers:
+ void push_front(const value_type& v);
+ void push_front(value_type&& v);
+ template<container-compatible-range<T> R>
+ void prepend_range(R&& rg); // C++23
+ void push_back(const value_type& v);
+ void push_back(value_type&& v);
+ template<container-compatible-range<T> R>
+ void append_range(R&& rg); // C++23
+ template <class... Args> reference emplace_front(Args&&... args); // reference in C++17
+ template <class... Args> reference emplace_back(Args&&... args); // reference in C++17
+ template <class... Args> iterator emplace(const_iterator p, Args&&... args);
+ iterator insert(const_iterator p, const value_type& v);
+ iterator insert(const_iterator p, value_type&& v);
+ iterator insert(const_iterator p, size_type n, const value_type& v);
+ template <class InputIterator>
+ iterator insert(const_iterator p, InputIterator f, InputIterator l);
+ template<container-compatible-range<T> R>
+ iterator insert_range(const_iterator position, R&& rg); // C++23
+ iterator insert(const_iterator p, initializer_list<value_type> il);
+ void pop_front();
+ void pop_back();
+ iterator erase(const_iterator p);
+ iterator erase(const_iterator f, const_iterator l);
+ void swap(deque& c)
+ noexcept(allocator_traits<allocator_type>::is_always_equal::value); // C++17
+ void clear() noexcept;
+};
+
+template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+ deque(InputIterator, InputIterator, Allocator = Allocator())
+ -> deque<typename iterator_traits<InputIterator>::value_type, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator = allocator<ranges::range_value_t<R>>>
+ deque(from_range_t, R&&, Allocator = Allocator())
+ -> deque<ranges::range_value_t<R>, Allocator>; // C++23
+
+template <class T, class Allocator>
+ bool operator==(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
+template <class T, class Allocator>
+ bool operator< (const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator>
+ bool operator!=(const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator>
+ bool operator> (const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator>
+ bool operator>=(const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator>
+ bool operator<=(const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
+template<class T, class Allocator>
+ synth-three-way-result<T> operator<=>(const deque<T, Allocator>& x,
+ const deque<T, Allocator>& y); // since C++20
+
+// specialized algorithms:
+template <class T, class Allocator>
+ void swap(deque<T,Allocator>& x, deque<T,Allocator>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class T, class Allocator, class U>
+ typename deque<T, Allocator>::size_type
+ erase(deque<T, Allocator>& c, const U& value); // C++20
+template <class T, class Allocator, class Predicate>
+ typename deque<T, Allocator>::size_type
+ erase_if(deque<T, Allocator>& c, Predicate pred); // C++20
+
+} // std
+
+*/
+
+#include <__algorithm/copy.h>
+#include <__algorithm/copy_backward.h>
+#include <__algorithm/copy_n.h>
+#include <__algorithm/equal.h>
+#include <__algorithm/fill_n.h>
+#include <__algorithm/lexicographical_compare.h>
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__algorithm/min.h>
+#include <__algorithm/remove.h>
+#include <__algorithm/remove_if.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__assert>
+#include <__config>
+#include <__debug_utils/sanitizers.h>
+#include <__format/enable_insertable.h>
+#include <__fwd/deque.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/next.h>
+#include <__iterator/prev.h>
+#include <__iterator/reverse_iterator.h>
+#include <__iterator/segmented_iterator.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator_destructor.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/temp_value.h>
+#include <__memory/unique_ptr.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__ranges/size.h>
+#include <__split_buffer>
+#include <__type_traits/is_allocator.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/swap.h>
+#include <limits>
+#include <stdexcept>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [deque.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ValueType, class _DiffType>
+struct __deque_block_size {
+ static const _DiffType value = sizeof(_ValueType) < 256 ? 4096 / sizeof(_ValueType) : 16;
+};
+
+template <class _ValueType,
+ class _Pointer,
+ class _Reference,
+ class _MapPointer,
+ class _DiffType,
+ _DiffType _BS =
+#ifdef _LIBCPP_ABI_INCOMPLETE_TYPES_IN_DEQUE
+ // Keep template parameter to avoid changing all template declarations thoughout
+ // this file.
+ 0
+#else
+ __deque_block_size<_ValueType, _DiffType>::value
+#endif
+ >
+class _LIBCPP_TEMPLATE_VIS __deque_iterator {
+ typedef _MapPointer __map_iterator;
+
+public:
+ typedef _Pointer pointer;
+ typedef _DiffType difference_type;
+
+private:
+ __map_iterator __m_iter_;
+ pointer __ptr_;
+
+ static const difference_type __block_size;
+
+public:
+ typedef _ValueType value_type;
+ typedef random_access_iterator_tag iterator_category;
+ typedef _Reference reference;
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator() _NOEXCEPT
+#if _LIBCPP_STD_VER >= 14
+ : __m_iter_(nullptr),
+ __ptr_(nullptr)
+#endif
+ {
+ }
+
+ template <class _Pp, class _Rp, class _MP, __enable_if_t<is_convertible<_Pp, pointer>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ __deque_iterator(const __deque_iterator<value_type, _Pp, _Rp, _MP, difference_type, _BS>& __it) _NOEXCEPT
+ : __m_iter_(__it.__m_iter_),
+ __ptr_(__it.__ptr_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return *__ptr_; }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return __ptr_; }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator& operator++() {
+ if (++__ptr_ - *__m_iter_ == __block_size) {
+ ++__m_iter_;
+ __ptr_ = *__m_iter_;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator operator++(int) {
+ __deque_iterator __tmp = *this;
+ ++(*this);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator& operator--() {
+ if (__ptr_ == *__m_iter_) {
+ --__m_iter_;
+ __ptr_ = *__m_iter_ + __block_size;
+ }
+ --__ptr_;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator operator--(int) {
+ __deque_iterator __tmp = *this;
+ --(*this);
+ return __tmp;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator& operator+=(difference_type __n) {
+ if (__n != 0) {
+ __n += __ptr_ - *__m_iter_;
+ if (__n > 0) {
+ __m_iter_ += __n / __block_size;
+ __ptr_ = *__m_iter_ + __n % __block_size;
+ } else // (__n < 0)
+ {
+ difference_type __z = __block_size - 1 - __n;
+ __m_iter_ -= __z / __block_size;
+ __ptr_ = *__m_iter_ + (__block_size - 1 - __z % __block_size);
+ }
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator& operator-=(difference_type __n) { return *this += -__n; }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator operator+(difference_type __n) const {
+ __deque_iterator __t(*this);
+ __t += __n;
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_iterator operator-(difference_type __n) const {
+ __deque_iterator __t(*this);
+ __t -= __n;
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend __deque_iterator operator+(difference_type __n, const __deque_iterator& __it) {
+ return __it + __n;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend difference_type operator-(const __deque_iterator& __x, const __deque_iterator& __y) {
+ if (__x != __y)
+ return (__x.__m_iter_ - __y.__m_iter_) * __block_size + (__x.__ptr_ - *__x.__m_iter_) -
+ (__y.__ptr_ - *__y.__m_iter_);
+ return 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI reference operator[](difference_type __n) const { return *(*this + __n); }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const __deque_iterator& __x, const __deque_iterator& __y) {
+ return __x.__ptr_ == __y.__ptr_;
+ }
+
+#if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI friend bool operator!=(const __deque_iterator& __x, const __deque_iterator& __y) {
+ return !(__x == __y);
+ }
+#endif
+
+ // TODO(mordante) disable these overloads in the LLVM 20 release.
+ _LIBCPP_HIDE_FROM_ABI friend bool operator<(const __deque_iterator& __x, const __deque_iterator& __y) {
+ return __x.__m_iter_ < __y.__m_iter_ || (__x.__m_iter_ == __y.__m_iter_ && __x.__ptr_ < __y.__ptr_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator>(const __deque_iterator& __x, const __deque_iterator& __y) {
+ return __y < __x;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator<=(const __deque_iterator& __x, const __deque_iterator& __y) {
+ return !(__y < __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator>=(const __deque_iterator& __x, const __deque_iterator& __y) {
+ return !(__x < __y);
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI friend strong_ordering operator<=>(const __deque_iterator& __x, const __deque_iterator& __y) {
+ if (__x.__m_iter_ < __y.__m_iter_)
+ return strong_ordering::less;
+
+ if (__x.__m_iter_ == __y.__m_iter_) {
+ if constexpr (three_way_comparable<pointer, strong_ordering>) {
+ return __x.__ptr_ <=> __y.__ptr_;
+ } else {
+ if (__x.__ptr_ < __y.__ptr_)
+ return strong_ordering::less;
+
+ if (__x.__ptr_ == __y.__ptr_)
+ return strong_ordering::equal;
+
+ return strong_ordering::greater;
+ }
+ }
+
+ return strong_ordering::greater;
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit __deque_iterator(__map_iterator __m, pointer __p) _NOEXCEPT
+ : __m_iter_(__m),
+ __ptr_(__p) {}
+
+ template <class _Tp, class _Ap>
+ friend class _LIBCPP_TEMPLATE_VIS deque;
+ template <class _Vp, class _Pp, class _Rp, class _MP, class _Dp, _Dp>
+ friend class _LIBCPP_TEMPLATE_VIS __deque_iterator;
+
+ template <class>
+ friend struct __segmented_iterator_traits;
+};
+
+template <class _ValueType, class _Pointer, class _Reference, class _MapPointer, class _DiffType, _DiffType _BlockSize>
+struct __segmented_iterator_traits<
+ __deque_iterator<_ValueType, _Pointer, _Reference, _MapPointer, _DiffType, _BlockSize> > {
+private:
+ using _Iterator = __deque_iterator<_ValueType, _Pointer, _Reference, _MapPointer, _DiffType, _BlockSize>;
+
+public:
+ using __is_segmented_iterator = true_type;
+ using __segment_iterator = _MapPointer;
+ using __local_iterator = _Pointer;
+
+ static _LIBCPP_HIDE_FROM_ABI __segment_iterator __segment(_Iterator __iter) { return __iter.__m_iter_; }
+ static _LIBCPP_HIDE_FROM_ABI __local_iterator __local(_Iterator __iter) { return __iter.__ptr_; }
+ static _LIBCPP_HIDE_FROM_ABI __local_iterator __begin(__segment_iterator __iter) { return *__iter; }
+
+ static _LIBCPP_HIDE_FROM_ABI __local_iterator __end(__segment_iterator __iter) {
+ return *__iter + _Iterator::__block_size;
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _Iterator __compose(__segment_iterator __segment, __local_iterator __local) {
+ if (__segment && __local == __end(__segment)) {
+ ++__segment;
+ return _Iterator(__segment, *__segment);
+ }
+ return _Iterator(__segment, __local);
+ }
+};
+
+template <class _ValueType, class _Pointer, class _Reference, class _MapPointer, class _DiffType, _DiffType _BlockSize>
+const _DiffType __deque_iterator<_ValueType, _Pointer, _Reference, _MapPointer, _DiffType, _BlockSize>::__block_size =
+ __deque_block_size<_ValueType, _DiffType>::value;
+
+template <class _Tp, class _Allocator /*= allocator<_Tp>*/>
+class _LIBCPP_TEMPLATE_VIS deque {
+public:
+ // types:
+
+ using value_type = _Tp;
+
+ using allocator_type = _Allocator;
+ using __alloc_traits = allocator_traits<allocator_type>;
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+ static_assert(is_same<typename allocator_type::value_type, value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+ using size_type = typename __alloc_traits::size_type;
+ using difference_type = typename __alloc_traits::difference_type;
+
+ using pointer = typename __alloc_traits::pointer;
+ using const_pointer = typename __alloc_traits::const_pointer;
+
+ using __pointer_allocator = __rebind_alloc<__alloc_traits, pointer>;
+ using __const_pointer_allocator = __rebind_alloc<__alloc_traits, const_pointer>;
+ using __map = __split_buffer<pointer, __pointer_allocator>;
+ using __map_alloc_traits = allocator_traits<__pointer_allocator>;
+ using __map_pointer = typename __map_alloc_traits::pointer;
+ using __map_const_pointer = typename allocator_traits<__const_pointer_allocator>::const_pointer;
+ using __map_const_iterator = typename __map::const_iterator;
+
+ using reference = value_type&;
+ using const_reference = const value_type&;
+
+ using iterator = __deque_iterator<value_type, pointer, reference, __map_pointer, difference_type>;
+ using const_iterator =
+ __deque_iterator<value_type, const_pointer, const_reference, __map_const_pointer, difference_type>;
+ using reverse_iterator = std::reverse_iterator<iterator>;
+ using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+
+ // A deque contains the following members which may be trivially relocatable:
+ // - __map: is a `__split_buffer`, see `__split_buffer` for more information on when it is trivially relocatable
+ // - size_type: is always trivially relocatable, since it is required to be an integral type
+ // - allocator_type: may not be trivially relocatable, so it's checked
+ // None of these are referencing the `deque` itself, so if all of them are trivially relocatable, `deque` is too.
+ using __trivially_relocatable = __conditional_t<
+ __libcpp_is_trivially_relocatable<__map>::value && __libcpp_is_trivially_relocatable<allocator_type>::value,
+ deque,
+ void>;
+
+ static_assert(is_nothrow_default_constructible<allocator_type>::value ==
+ is_nothrow_default_constructible<__pointer_allocator>::value,
+ "rebinding an allocator should not change exception guarantees");
+ static_assert(is_nothrow_move_constructible<allocator_type>::value ==
+ is_nothrow_move_constructible<typename __map::allocator_type>::value,
+ "rebinding an allocator should not change exception guarantees");
+
+private:
+ struct __deque_block_range {
+ explicit _LIBCPP_HIDE_FROM_ABI __deque_block_range(pointer __b, pointer __e) _NOEXCEPT
+ : __begin_(__b),
+ __end_(__e) {}
+ const pointer __begin_;
+ const pointer __end_;
+ };
+
+ struct __deque_range {
+ iterator __pos_;
+ const iterator __end_;
+
+ _LIBCPP_HIDE_FROM_ABI __deque_range(iterator __pos, iterator __e) _NOEXCEPT : __pos_(__pos), __end_(__e) {}
+
+ explicit _LIBCPP_HIDE_FROM_ABI operator bool() const _NOEXCEPT { return __pos_ != __end_; }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_range begin() const { return *this; }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_range end() const { return __deque_range(__end_, __end_); }
+ _LIBCPP_HIDE_FROM_ABI __deque_block_range operator*() const _NOEXCEPT {
+ if (__pos_.__m_iter_ == __end_.__m_iter_) {
+ return __deque_block_range(__pos_.__ptr_, __end_.__ptr_);
+ }
+ return __deque_block_range(__pos_.__ptr_, *__pos_.__m_iter_ + __block_size);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __deque_range& operator++() _NOEXCEPT {
+ if (__pos_.__m_iter_ == __end_.__m_iter_) {
+ __pos_ = __end_;
+ } else {
+ ++__pos_.__m_iter_;
+ __pos_.__ptr_ = *__pos_.__m_iter_;
+ }
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(__deque_range const& __lhs, __deque_range const& __rhs) {
+ return __lhs.__pos_ == __rhs.__pos_;
+ }
+ _LIBCPP_HIDE_FROM_ABI friend bool operator!=(__deque_range const& __lhs, __deque_range const& __rhs) {
+ return !(__lhs == __rhs);
+ }
+ };
+
+ struct _ConstructTransaction {
+ _LIBCPP_HIDE_FROM_ABI _ConstructTransaction(deque* __db, __deque_block_range& __r)
+ : __pos_(__r.__begin_), __end_(__r.__end_), __begin_(__r.__begin_), __base_(__db) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~_ConstructTransaction() { __base_->__size() += (__pos_ - __begin_); }
+
+ pointer __pos_;
+ const pointer __end_;
+
+ private:
+ const pointer __begin_;
+ deque* const __base_;
+ };
+
+ static const difference_type __block_size;
+
+ __map __map_;
+ size_type __start_;
+ __compressed_pair<size_type, allocator_type> __size_;
+
+public:
+ // construct/copy/destroy:
+ _LIBCPP_HIDE_FROM_ABI deque() _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
+ : __start_(0), __size_(0, __default_init_tag()) {
+ __annotate_new(0);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~deque() {
+ clear();
+ __annotate_delete();
+ typename __map::iterator __i = __map_.begin();
+ typename __map::iterator __e = __map_.end();
+ for (; __i != __e; ++__i)
+ __alloc_traits::deallocate(__alloc(), *__i, __block_size);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit deque(const allocator_type& __a)
+ : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
+ __annotate_new(0);
+ }
+
+ explicit _LIBCPP_HIDE_FROM_ABI deque(size_type __n);
+#if _LIBCPP_STD_VER >= 14
+ explicit _LIBCPP_HIDE_FROM_ABI deque(size_type __n, const _Allocator& __a);
+#endif
+ _LIBCPP_HIDE_FROM_ABI deque(size_type __n, const value_type& __v);
+
+ template <__enable_if_t<__is_allocator<_Allocator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI deque(size_type __n, const value_type& __v, const allocator_type& __a)
+ : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
+ __annotate_new(0);
+ if (__n > 0)
+ __append(__n, __v);
+ }
+
+ template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI deque(_InputIter __f, _InputIter __l);
+ template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI deque(_InputIter __f, _InputIter __l, const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI deque(from_range_t, _Range&& __range, const allocator_type& __a = allocator_type())
+ : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ __append_with_size(ranges::begin(__range), ranges::distance(__range));
+
+ } else {
+ for (auto&& __e : __range) {
+ emplace_back(std::forward<decltype(__e)>(__e));
+ }
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI deque(const deque& __c);
+ _LIBCPP_HIDE_FROM_ABI deque(const deque& __c, const __type_identity_t<allocator_type>& __a);
+
+ _LIBCPP_HIDE_FROM_ABI deque& operator=(const deque& __c);
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI deque(initializer_list<value_type> __il);
+ _LIBCPP_HIDE_FROM_ABI deque(initializer_list<value_type> __il, const allocator_type& __a);
+
+ _LIBCPP_HIDE_FROM_ABI deque& operator=(initializer_list<value_type> __il) {
+ assign(__il);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI deque(deque&& __c) noexcept(is_nothrow_move_constructible<allocator_type>::value);
+ _LIBCPP_HIDE_FROM_ABI deque(deque&& __c, const __type_identity_t<allocator_type>& __a);
+ _LIBCPP_HIDE_FROM_ABI deque&
+ operator=(deque&& __c) noexcept(__alloc_traits::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value);
+
+ _LIBCPP_HIDE_FROM_ABI void assign(initializer_list<value_type> __il) { assign(__il.begin(), __il.end()); }
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class _InputIter,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value &&
+ !__has_random_access_iterator_category<_InputIter>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void assign(_InputIter __f, _InputIter __l);
+ template <class _RAIter, __enable_if_t<__has_random_access_iterator_category<_RAIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void assign(_RAIter __f, _RAIter __l);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void assign_range(_Range&& __range) {
+ if constexpr (ranges::random_access_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ __assign_with_size_random_access(ranges::begin(__range), __n);
+
+ } else if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ __assign_with_size(ranges::begin(__range), __n);
+
+ } else {
+ __assign_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void assign(size_type __n, const value_type& __v);
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI allocator_type& __alloc() _NOEXCEPT { return __size_.second(); }
+ _LIBCPP_HIDE_FROM_ABI const allocator_type& __alloc() const _NOEXCEPT { return __size_.second(); }
+
+ // iterators:
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT {
+ __map_pointer __mp = __map_.begin() + __start_ / __block_size;
+ return iterator(__mp, __map_.empty() ? 0 : *__mp + __start_ % __block_size);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT {
+ __map_const_pointer __mp = static_cast<__map_const_pointer>(__map_.begin() + __start_ / __block_size);
+ return const_iterator(__mp, __map_.empty() ? 0 : *__mp + __start_ % __block_size);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT {
+ size_type __p = size() + __start_;
+ __map_pointer __mp = __map_.begin() + __p / __block_size;
+ return iterator(__mp, __map_.empty() ? 0 : *__mp + __p % __block_size);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT {
+ size_type __p = size() + __start_;
+ __map_const_pointer __mp = static_cast<__map_const_pointer>(__map_.begin() + __p / __block_size);
+ return const_iterator(__mp, __map_.empty() ? 0 : *__mp + __p % __block_size);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() _NOEXCEPT { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const _NOEXCEPT { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() _NOEXCEPT { return reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const _NOEXCEPT { return const_reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const _NOEXCEPT { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const _NOEXCEPT { return const_reverse_iterator(begin()); }
+
+ // capacity:
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __size(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type& __size() _NOEXCEPT { return __size_.first(); }
+ _LIBCPP_HIDE_FROM_ABI const size_type& __size() const _NOEXCEPT { return __size_.first(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT {
+ return std::min<size_type>(__alloc_traits::max_size(__alloc()), numeric_limits<difference_type>::max());
+ }
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n);
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n, const value_type& __v);
+ _LIBCPP_HIDE_FROM_ABI void shrink_to_fit() _NOEXCEPT;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return size() == 0; }
+
+ // element access:
+ _LIBCPP_HIDE_FROM_ABI reference operator[](size_type __i) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI const_reference operator[](size_type __i) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI reference at(size_type __i);
+ _LIBCPP_HIDE_FROM_ABI const_reference at(size_type __i) const;
+ _LIBCPP_HIDE_FROM_ABI reference front() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI const_reference front() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI reference back() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI const_reference back() const _NOEXCEPT;
+
+ // 23.2.2.3 modifiers:
+ _LIBCPP_HIDE_FROM_ABI void push_front(const value_type& __v);
+ _LIBCPP_HIDE_FROM_ABI void push_back(const value_type& __v);
+#ifndef _LIBCPP_CXX03_LANG
+# if _LIBCPP_STD_VER >= 17
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI reference emplace_front(_Args&&... __args);
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI reference emplace_back(_Args&&... __args);
+# else
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void emplace_front(_Args&&... __args);
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void emplace_back(_Args&&... __args);
+# endif
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace(const_iterator __p, _Args&&... __args);
+
+ _LIBCPP_HIDE_FROM_ABI void push_front(value_type&& __v);
+ _LIBCPP_HIDE_FROM_ABI void push_back(value_type&& __v);
+
+# if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void prepend_range(_Range&& __range) {
+ insert_range(begin(), std::forward<_Range>(__range));
+ }
+
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void append_range(_Range&& __range) {
+ insert_range(end(), std::forward<_Range>(__range));
+ }
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __v);
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, initializer_list<value_type> __il) {
+ return insert(__p, __il.begin(), __il.end());
+ }
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __v);
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, size_type __n, const value_type& __v);
+ template <class _InputIter, __enable_if_t<__has_exactly_input_iterator_category<_InputIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, _InputIter __f, _InputIter __l);
+ template <class _ForwardIterator,
+ __enable_if_t<__has_exactly_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, _ForwardIterator __f, _ForwardIterator __l);
+ template <class _BiIter, __enable_if_t<__has_bidirectional_iterator_category<_BiIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, _BiIter __f, _BiIter __l);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_range(const_iterator __position, _Range&& __range) {
+ if constexpr (ranges::bidirectional_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ return __insert_bidirectional(__position, ranges::begin(__range), ranges::end(__range), __n);
+
+ } else if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ return __insert_with_size(__position, ranges::begin(__range), __n);
+
+ } else {
+ return __insert_with_sentinel(__position, ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void pop_front();
+ _LIBCPP_HIDE_FROM_ABI void pop_back();
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p);
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __f, const_iterator __l);
+
+ _LIBCPP_HIDE_FROM_ABI void swap(deque& __c)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT;
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>);
+#endif
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI bool __invariants() const {
+ if (!__map_.__invariants())
+ return false;
+ if (__map_.size() >= size_type(-1) / __block_size)
+ return false;
+ for (__map_const_iterator __i = __map_.begin(), __e = __map_.end(); __i != __e; ++__i)
+ if (*__i == nullptr)
+ return false;
+ if (__map_.size() != 0) {
+ if (size() >= __map_.size() * __block_size)
+ return false;
+ if (__start_ >= __map_.size() * __block_size - size())
+ return false;
+ } else {
+ if (size() != 0)
+ return false;
+ if (__start_ != 0)
+ return false;
+ }
+ return true;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(deque& __c)
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_move_assignment::value ||
+ is_nothrow_move_assignable<allocator_type>::value) {
+ __move_assign_alloc(__c, integral_constant<bool, __alloc_traits::propagate_on_container_move_assignment::value>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(deque& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
+ __alloc() = std::move(__c.__alloc());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(deque&, false_type) _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(deque& __c)
+ _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value&&
+ is_nothrow_move_assignable<allocator_type>::value) {
+ __map_ = std::move(__c.__map_);
+ __start_ = __c.__start_;
+ __size() = __c.size();
+ __move_assign_alloc(__c);
+ __c.__start_ = __c.__size() = 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI static size_type __recommend_blocks(size_type __n) {
+ return __n / __block_size + (__n % __block_size != 0);
+ }
+ _LIBCPP_HIDE_FROM_ABI size_type __capacity() const {
+ return __map_.size() == 0 ? 0 : __map_.size() * __block_size - 1;
+ }
+ _LIBCPP_HIDE_FROM_ABI size_type __block_count() const { return __map_.size(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type __front_spare() const { return __start_; }
+ _LIBCPP_HIDE_FROM_ABI size_type __front_spare_blocks() const { return __front_spare() / __block_size; }
+ _LIBCPP_HIDE_FROM_ABI size_type __back_spare() const { return __capacity() - (__start_ + size()); }
+ _LIBCPP_HIDE_FROM_ABI size_type __back_spare_blocks() const { return __back_spare() / __block_size; }
+
+private:
+ enum __asan_annotation_type { __asan_unposion, __asan_poison };
+
+ enum __asan_annotation_place {
+ __asan_front_moved,
+ __asan_back_moved,
+ };
+
+ _LIBCPP_HIDE_FROM_ABI void __annotate_from_to(
+ size_type __beg,
+ size_type __end,
+ __asan_annotation_type __annotation_type,
+ __asan_annotation_place __place) const _NOEXCEPT {
+ (void)__beg;
+ (void)__end;
+ (void)__annotation_type;
+ (void)__place;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ // __beg - index of the first item to annotate
+ // __end - index behind the last item to annotate (so last item + 1)
+ // __annotation_type - __asan_unposion or __asan_poison
+ // __place - __asan_front_moved or __asan_back_moved
+ // Note: All indexes in __map_
+ if (__beg == __end)
+ return;
+ // __annotations_beg_map - first chunk which annotations we want to modify
+ // __annotations_end_map - last chunk which annotations we want to modify
+ // NOTE: if __end % __block_size == 0, __annotations_end_map points at the next block, which may not exist
+ __map_const_iterator __annotations_beg_map = __map_.begin() + __beg / __block_size;
+ __map_const_iterator __annotations_end_map = __map_.begin() + __end / __block_size;
+
+ bool const __poisoning = __annotation_type == __asan_poison;
+ // __old_c_beg_index - index of the first element in old container
+ // __old_c_end_index - index of the end of old container (last + 1)
+ // Note: may be outside the area we are annotating
+ size_t __old_c_beg_index = (__poisoning && __place == __asan_front_moved) ? __beg : __start_;
+ size_t __old_c_end_index = (__poisoning && __place == __asan_back_moved) ? __end : __start_ + size();
+ bool const __front = __place == __asan_front_moved;
+
+ if (__poisoning && empty()) {
+ // Special case: we shouldn't trust __start_
+ __old_c_beg_index = __beg;
+ __old_c_end_index = __end;
+ }
+ // __old_c_beg_map - memory block (chunk) with first element
+ // __old_c_end_map - memory block (chunk) with end of old container
+ // Note: if __old_c_end_index % __block_size == 0, __old_c_end_map points at the next block,
+ // which may not exist
+ __map_const_iterator __old_c_beg_map = __map_.begin() + __old_c_beg_index / __block_size;
+ __map_const_iterator __old_c_end_map = __map_.begin() + __old_c_end_index / __block_size;
+
+ // One edge (front/end) of the container was moved and one was not modified.
+ // __new_edge_index - index of new edge
+ // __new_edge_map - memory block (chunk) with new edge, it always equals to
+ // __annotations_beg_map or __annotations_end_map
+ // __old_edge_map - memory block (chunk) with old edge, it always equals to
+ // __old_c_beg_map or __old_c_end_map
+ size_t __new_edge_index = (__poisoning ^ __front) ? __beg : __end;
+ __map_const_iterator __new_edge_map = __map_.begin() + __new_edge_index / __block_size;
+ __map_const_iterator __old_edge_map = __front ? __old_c_end_map : __old_c_beg_map;
+
+ // We iterate over map pointers (chunks) and fully poison all memory blocks between the first and the last.
+ // First and last chunk may be partially poisoned.
+ // __annotate_end_map may point at not existing chunk, therefore we have to have a check for it.
+ for (__map_const_iterator __map_it = __annotations_beg_map; __map_it <= __annotations_end_map; ++__map_it) {
+ if (__map_it == __annotations_end_map && __end % __block_size == 0)
+ // Chunk may not exist, but nothing to do here anyway
+ break;
+
+ // The beginning and the end of the current memory block
+ const void* __mem_beg = std::__to_address(*__map_it);
+ const void* __mem_end = std::__to_address(*__map_it + __block_size);
+
+ // The beginning of memory-in-use in the memory block before container modification
+ const void* __old_beg =
+ (__map_it == __old_c_beg_map) ? std::__to_address(*__map_it + (__old_c_beg_index % __block_size)) : __mem_beg;
+
+ // The end of memory-in-use in the memory block before container modification
+ const void* __old_end;
+ if (__map_it < __old_c_beg_map || __map_it > __old_c_end_map || (!__poisoning && empty()))
+ __old_end = __old_beg;
+ else
+ __old_end = (__map_it == __old_c_end_map)
+ ? std::__to_address(*__map_it + (__old_c_end_index % __block_size))
+ : __mem_end;
+
+ // New edge of the container in current memory block
+ // If the edge is in a different chunk it points on corresponding end of the memory block
+ const void* __new_edge;
+ if (__map_it == __new_edge_map)
+ __new_edge = std::__to_address(*__map_it + (__new_edge_index % __block_size));
+ else
+ __new_edge = (__poisoning ^ __front) ? __mem_beg : __mem_end;
+
+ // Not modified edge of the container
+ // If the edge is in a different chunk it points on corresponding end of the memory block
+ const void* __old_edge;
+ if (__map_it == __old_edge_map)
+ __old_edge = __front ? __old_end : __old_beg;
+ else
+ __old_edge = __front ? __mem_end : __mem_beg;
+
+ // __new_beg - the beginning of memory-in-use in the memory block after container modification
+ // __new_end - the end of memory-in-use in the memory block after container modification
+ const void* __new_beg = __front ? __new_edge : __old_edge;
+ const void* __new_end = __front ? __old_edge : __new_edge;
+
+ std::__annotate_double_ended_contiguous_container<_Allocator>(
+ __mem_beg, __mem_end, __old_beg, __old_end, __new_beg, __new_end);
+ }
+#endif // !_LIBCPP_HAS_NO_ASAN
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __annotate_new(size_type __current_size) const _NOEXCEPT {
+ (void)__current_size;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ if (__current_size == 0)
+ __annotate_from_to(0, __map_.size() * __block_size, __asan_poison, __asan_back_moved);
+ else {
+ __annotate_from_to(0, __start_, __asan_poison, __asan_front_moved);
+ __annotate_from_to(__start_ + __current_size, __map_.size() * __block_size, __asan_poison, __asan_back_moved);
+ }
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __annotate_delete() const _NOEXCEPT {
+#ifndef _LIBCPP_HAS_NO_ASAN
+ if (empty()) {
+ for (size_t __i = 0; __i < __map_.size(); ++__i) {
+ __annotate_whole_block(__i, __asan_unposion);
+ }
+ } else {
+ __annotate_from_to(0, __start_, __asan_unposion, __asan_front_moved);
+ __annotate_from_to(__start_ + size(), __map_.size() * __block_size, __asan_unposion, __asan_back_moved);
+ }
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __annotate_increase_front(size_type __n) const _NOEXCEPT {
+ (void)__n;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __annotate_from_to(__start_ - __n, __start_, __asan_unposion, __asan_front_moved);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __annotate_increase_back(size_type __n) const _NOEXCEPT {
+ (void)__n;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __annotate_from_to(__start_ + size(), __start_ + size() + __n, __asan_unposion, __asan_back_moved);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __annotate_shrink_front(size_type __old_size, size_type __old_start) const _NOEXCEPT {
+ (void)__old_size;
+ (void)__old_start;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __annotate_from_to(__old_start, __old_start + (__old_size - size()), __asan_poison, __asan_front_moved);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __annotate_shrink_back(size_type __old_size, size_type __old_start) const _NOEXCEPT {
+ (void)__old_size;
+ (void)__old_start;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __annotate_from_to(__old_start + size(), __old_start + __old_size, __asan_poison, __asan_back_moved);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __annotate_poison_block(const void* __beginning, const void* __end) const _NOEXCEPT {
+ std::__annotate_double_ended_contiguous_container<_Allocator>(__beginning, __end, __beginning, __end, __end, __end);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void
+ __annotate_whole_block(size_t __block_index, __asan_annotation_type __annotation_type) const _NOEXCEPT {
+ (void)__block_index;
+ (void)__annotation_type;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __map_const_iterator __block_it = __map_.begin() + __block_index;
+ const void* __block_start = std::__to_address(*__block_it);
+ const void* __block_end = std::__to_address(*__block_it + __block_size);
+
+ if (__annotation_type == __asan_poison)
+ __annotate_poison_block(__block_start, __block_end);
+ else {
+ std::__annotate_double_ended_contiguous_container<_Allocator>(
+ __block_start, __block_end, __block_start, __block_start, __block_start, __block_end);
+ }
+#endif
+ }
+#if !defined(_LIBCPP_HAS_NO_ASAN)
+
+public:
+ _LIBCPP_HIDE_FROM_ABI bool __verify_asan_annotations() const _NOEXCEPT {
+ // This function tests deque object annotations.
+ if (empty()) {
+ for (__map_const_iterator __it = __map_.begin(); __it != __map_.end(); ++__it) {
+ if (!__sanitizer_verify_double_ended_contiguous_container(
+ std::__to_address(*__it),
+ std::__to_address(*__it),
+ std::__to_address(*__it),
+ std::__to_address(*__it + __block_size)))
+ return false;
+ }
+
+ return true;
+ }
+
+ size_type __end = __start_ + size();
+ __map_const_iterator __first_mp = __map_.begin() + __start_ / __block_size;
+ __map_const_iterator __last_mp = __map_.begin() + (__end - 1) / __block_size;
+
+ // Pointers to first and after last elements
+ // Those can be in different deque blocks
+ const void* __p_beg = std::__to_address(*__first_mp + (__start_ % __block_size));
+ const void* __p_end =
+ std::__to_address(*__last_mp + ((__end % __block_size == 0) ? __block_size : __end % __block_size));
+
+ for (__map_const_iterator __it = __map_.begin(); __it != __map_.end(); ++__it) {
+ // Go over all blocks, find the place we are in and verify its annotations
+ // Note that __p_end points *behind* the last item.
+
+ // - blocks before the first block with container elements
+ // - first block with items
+ // - last block with items
+ // - blocks after last block with ciontainer elements
+
+ // Is the block before or after deque blocks that contain elements?
+ if (__it < __first_mp || __it > __last_mp) {
+ if (!__sanitizer_verify_double_ended_contiguous_container(
+ std::__to_address(*__it),
+ std::__to_address(*__it),
+ std::__to_address(*__it),
+ std::__to_address(*__it + __block_size)))
+ return false;
+ } else {
+ const void* __containers_buffer_beg = (__it == __first_mp) ? __p_beg : (const void*)std::__to_address(*__it);
+ const void* __containers_buffer_end =
+ (__it == __last_mp) ? __p_end : (const void*)std::__to_address(*__it + __block_size);
+ if (!__sanitizer_verify_double_ended_contiguous_container(
+ std::__to_address(*__it),
+ __containers_buffer_beg,
+ __containers_buffer_end,
+ std::__to_address(*__it + __block_size))) {
+ return false;
+ }
+ }
+ }
+ return true;
+ }
+
+private:
+#endif // _LIBCPP_VERIFY_ASAN_DEQUE_ANNOTATIONS
+ _LIBCPP_HIDE_FROM_ABI bool __maybe_remove_front_spare(bool __keep_one = true) {
+ if (__front_spare_blocks() >= 2 || (!__keep_one && __front_spare_blocks())) {
+ __annotate_whole_block(0, __asan_unposion);
+ __alloc_traits::deallocate(__alloc(), __map_.front(), __block_size);
+ __map_.pop_front();
+ __start_ -= __block_size;
+ return true;
+ }
+ return false;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool __maybe_remove_back_spare(bool __keep_one = true) {
+ if (__back_spare_blocks() >= 2 || (!__keep_one && __back_spare_blocks())) {
+ __annotate_whole_block(__map_.size() - 1, __asan_unposion);
+ __alloc_traits::deallocate(__alloc(), __map_.back(), __block_size);
+ __map_.pop_back();
+ return true;
+ }
+ return false;
+ }
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI void __assign_with_sentinel(_Iterator __f, _Sentinel __l);
+
+ template <class _RandomAccessIterator>
+ _LIBCPP_HIDE_FROM_ABI void __assign_with_size_random_access(_RandomAccessIterator __f, difference_type __n);
+ template <class _Iterator>
+ _LIBCPP_HIDE_FROM_ABI void __assign_with_size(_Iterator __f, difference_type __n);
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_with_sentinel(const_iterator __p, _Iterator __f, _Sentinel __l);
+
+ template <class _Iterator>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_with_size(const_iterator __p, _Iterator __f, size_type __n);
+
+ template <class _BiIter, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI iterator
+ __insert_bidirectional(const_iterator __p, _BiIter __f, _Sentinel __sent, size_type __n);
+ template <class _BiIter>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_bidirectional(const_iterator __p, _BiIter __f, _BiIter __l, size_type __n);
+
+ template <class _InpIter, __enable_if_t<__has_exactly_input_iterator_category<_InpIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void __append(_InpIter __f, _InpIter __l);
+ template <class _ForIter, __enable_if_t<__has_forward_iterator_category<_ForIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void __append(_ForIter __f, _ForIter __l);
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void __append_with_size(_InputIterator __from, size_type __n);
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI void __append_with_sentinel(_InputIterator __f, _Sentinel __l);
+
+ _LIBCPP_HIDE_FROM_ABI void __append(size_type __n);
+ _LIBCPP_HIDE_FROM_ABI void __append(size_type __n, const value_type& __v);
+ _LIBCPP_HIDE_FROM_ABI void __erase_to_end(const_iterator __f);
+ _LIBCPP_HIDE_FROM_ABI void __add_front_capacity();
+ _LIBCPP_HIDE_FROM_ABI void __add_front_capacity(size_type __n);
+ _LIBCPP_HIDE_FROM_ABI void __add_back_capacity();
+ _LIBCPP_HIDE_FROM_ABI void __add_back_capacity(size_type __n);
+ _LIBCPP_HIDE_FROM_ABI iterator __move_and_check(iterator __f, iterator __l, iterator __r, const_pointer& __vt);
+ _LIBCPP_HIDE_FROM_ABI iterator
+ __move_backward_and_check(iterator __f, iterator __l, iterator __r, const_pointer& __vt);
+ _LIBCPP_HIDE_FROM_ABI void __move_construct_and_check(iterator __f, iterator __l, iterator __r, const_pointer& __vt);
+ _LIBCPP_HIDE_FROM_ABI void
+ __move_construct_backward_and_check(iterator __f, iterator __l, iterator __r, const_pointer& __vt);
+
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const deque& __c) {
+ __copy_assign_alloc(__c, integral_constant<bool, __alloc_traits::propagate_on_container_copy_assignment::value>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const deque& __c, true_type) {
+ if (__alloc() != __c.__alloc()) {
+ clear();
+ shrink_to_fit();
+ }
+ __alloc() = __c.__alloc();
+ __map_.__alloc() = __c.__map_.__alloc();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const deque&, false_type) {}
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(deque& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(deque& __c, false_type);
+};
+
+template <class _Tp, class _Alloc>
+_LIBCPP_CONSTEXPR const typename allocator_traits<_Alloc>::difference_type deque<_Tp, _Alloc>::__block_size =
+ __deque_block_size<value_type, difference_type>::value;
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Alloc = allocator<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+deque(_InputIterator, _InputIterator) -> deque<__iter_value_type<_InputIterator>, _Alloc>;
+
+template <class _InputIterator,
+ class _Alloc,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+deque(_InputIterator, _InputIterator, _Alloc) -> deque<__iter_value_type<_InputIterator>, _Alloc>;
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Alloc = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+deque(from_range_t, _Range&&, _Alloc = _Alloc()) -> deque<ranges::range_value_t<_Range>, _Alloc>;
+#endif
+
+template <class _Tp, class _Allocator>
+deque<_Tp, _Allocator>::deque(size_type __n) : __start_(0), __size_(0, __default_init_tag()) {
+ __annotate_new(0);
+ if (__n > 0)
+ __append(__n);
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp, class _Allocator>
+deque<_Tp, _Allocator>::deque(size_type __n, const _Allocator& __a)
+ : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
+ __annotate_new(0);
+ if (__n > 0)
+ __append(__n);
+}
+#endif
+
+template <class _Tp, class _Allocator>
+deque<_Tp, _Allocator>::deque(size_type __n, const value_type& __v) : __start_(0), __size_(0, __default_init_tag()) {
+ __annotate_new(0);
+ if (__n > 0)
+ __append(__n, __v);
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> >
+deque<_Tp, _Allocator>::deque(_InputIter __f, _InputIter __l) : __start_(0), __size_(0, __default_init_tag()) {
+ __annotate_new(0);
+ __append(__f, __l);
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> >
+deque<_Tp, _Allocator>::deque(_InputIter __f, _InputIter __l, const allocator_type& __a)
+ : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
+ __annotate_new(0);
+ __append(__f, __l);
+}
+
+template <class _Tp, class _Allocator>
+deque<_Tp, _Allocator>::deque(const deque& __c)
+ : __map_(__pointer_allocator(__alloc_traits::select_on_container_copy_construction(__c.__alloc()))),
+ __start_(0),
+ __size_(0, __map_.__alloc()) {
+ __annotate_new(0);
+ __append(__c.begin(), __c.end());
+}
+
+template <class _Tp, class _Allocator>
+deque<_Tp, _Allocator>::deque(const deque& __c, const __type_identity_t<allocator_type>& __a)
+ : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
+ __annotate_new(0);
+ __append(__c.begin(), __c.end());
+}
+
+template <class _Tp, class _Allocator>
+deque<_Tp, _Allocator>& deque<_Tp, _Allocator>::operator=(const deque& __c) {
+ if (this != std::addressof(__c)) {
+ __copy_assign_alloc(__c);
+ assign(__c.begin(), __c.end());
+ }
+ return *this;
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Allocator>
+deque<_Tp, _Allocator>::deque(initializer_list<value_type> __il) : __start_(0), __size_(0, __default_init_tag()) {
+ __annotate_new(0);
+ __append(__il.begin(), __il.end());
+}
+
+template <class _Tp, class _Allocator>
+deque<_Tp, _Allocator>::deque(initializer_list<value_type> __il, const allocator_type& __a)
+ : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
+ __annotate_new(0);
+ __append(__il.begin(), __il.end());
+}
+
+template <class _Tp, class _Allocator>
+inline deque<_Tp, _Allocator>::deque(deque&& __c) noexcept(is_nothrow_move_constructible<allocator_type>::value)
+ : __map_(std::move(__c.__map_)), __start_(std::move(__c.__start_)), __size_(std::move(__c.__size_)) {
+ __c.__start_ = 0;
+ __c.__size() = 0;
+}
+
+template <class _Tp, class _Allocator>
+inline deque<_Tp, _Allocator>::deque(deque&& __c, const __type_identity_t<allocator_type>& __a)
+ : __map_(std::move(__c.__map_), __pointer_allocator(__a)),
+ __start_(std::move(__c.__start_)),
+ __size_(std::move(__c.__size()), __a) {
+ if (__a == __c.__alloc()) {
+ __c.__start_ = 0;
+ __c.__size() = 0;
+ } else {
+ __map_.clear();
+ __start_ = 0;
+ __size() = 0;
+ typedef move_iterator<iterator> _Ip;
+ assign(_Ip(__c.begin()), _Ip(__c.end()));
+ }
+}
+
+template <class _Tp, class _Allocator>
+inline deque<_Tp, _Allocator>& deque<_Tp, _Allocator>::operator=(deque&& __c) noexcept(
+ __alloc_traits::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value) {
+ __move_assign(__c, integral_constant<bool, __alloc_traits::propagate_on_container_move_assignment::value>());
+ return *this;
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__move_assign(deque& __c, false_type) {
+ if (__alloc() != __c.__alloc()) {
+ typedef move_iterator<iterator> _Ip;
+ assign(_Ip(__c.begin()), _Ip(__c.end()));
+ } else
+ __move_assign(__c, true_type());
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__move_assign(deque& __c,
+ true_type) noexcept(is_nothrow_move_assignable<allocator_type>::value) {
+ clear();
+ shrink_to_fit();
+ __move_assign(__c);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Allocator>
+template <class _InputIter,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value &&
+ !__has_random_access_iterator_category<_InputIter>::value,
+ int> >
+void deque<_Tp, _Allocator>::assign(_InputIter __f, _InputIter __l) {
+ __assign_with_sentinel(__f, __l);
+}
+
+template <class _Tp, class _Allocator>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI void deque<_Tp, _Allocator>::__assign_with_sentinel(_Iterator __f, _Sentinel __l) {
+ iterator __i = begin();
+ iterator __e = end();
+ for (; __f != __l && __i != __e; ++__f, (void)++__i)
+ *__i = *__f;
+ if (__f != __l)
+ __append_with_sentinel(std::move(__f), std::move(__l));
+ else
+ __erase_to_end(__i);
+}
+
+template <class _Tp, class _Allocator>
+template <class _RAIter, __enable_if_t<__has_random_access_iterator_category<_RAIter>::value, int> >
+void deque<_Tp, _Allocator>::assign(_RAIter __f, _RAIter __l) {
+ __assign_with_size_random_access(__f, __l - __f);
+}
+
+template <class _Tp, class _Allocator>
+template <class _RandomAccessIterator>
+_LIBCPP_HIDE_FROM_ABI void
+deque<_Tp, _Allocator>::__assign_with_size_random_access(_RandomAccessIterator __f, difference_type __n) {
+ if (static_cast<size_type>(__n) > size()) {
+ auto __l = __f + size();
+ std::copy(__f, __l, begin());
+ __append_with_size(__l, __n - size());
+ } else
+ __erase_to_end(std::copy_n(__f, __n, begin()));
+}
+
+template <class _Tp, class _Allocator>
+template <class _Iterator>
+_LIBCPP_HIDE_FROM_ABI void deque<_Tp, _Allocator>::__assign_with_size(_Iterator __f, difference_type __n) {
+ if (static_cast<size_type>(__n) > size()) {
+ auto __added_size = __n - size();
+
+ auto __i = begin();
+ for (auto __count = size(); __count != 0; --__count) {
+ *__i++ = *__f++;
+ }
+
+ __append_with_size(__f, __added_size);
+
+ } else {
+ __erase_to_end(std::copy_n(__f, __n, begin()));
+ }
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::assign(size_type __n, const value_type& __v) {
+ if (__n > size()) {
+ std::fill_n(begin(), size(), __v);
+ __n -= size();
+ __append(__n, __v);
+ } else
+ __erase_to_end(std::fill_n(begin(), __n, __v));
+}
+
+template <class _Tp, class _Allocator>
+inline _Allocator deque<_Tp, _Allocator>::get_allocator() const _NOEXCEPT {
+ return __alloc();
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::resize(size_type __n) {
+ if (__n > size())
+ __append(__n - size());
+ else if (__n < size())
+ __erase_to_end(begin() + __n);
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::resize(size_type __n, const value_type& __v) {
+ if (__n > size())
+ __append(__n - size(), __v);
+ else if (__n < size())
+ __erase_to_end(begin() + __n);
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT {
+ allocator_type& __a = __alloc();
+ if (empty()) {
+ __annotate_delete();
+ while (__map_.size() > 0) {
+ __alloc_traits::deallocate(__a, __map_.back(), __block_size);
+ __map_.pop_back();
+ }
+ __start_ = 0;
+ } else {
+ __maybe_remove_front_spare(/*__keep_one=*/false);
+ __maybe_remove_back_spare(/*__keep_one=*/false);
+ }
+ __map_.shrink_to_fit();
+}
+
+template <class _Tp, class _Allocator>
+inline typename deque<_Tp, _Allocator>::reference deque<_Tp, _Allocator>::operator[](size_type __i) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < size(), "deque::operator[] index out of bounds");
+ size_type __p = __start_ + __i;
+ return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
+}
+
+template <class _Tp, class _Allocator>
+inline typename deque<_Tp, _Allocator>::const_reference
+deque<_Tp, _Allocator>::operator[](size_type __i) const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < size(), "deque::operator[] index out of bounds");
+ size_type __p = __start_ + __i;
+ return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
+}
+
+template <class _Tp, class _Allocator>
+inline typename deque<_Tp, _Allocator>::reference deque<_Tp, _Allocator>::at(size_type __i) {
+ if (__i >= size())
+ std::__throw_out_of_range("deque");
+ size_type __p = __start_ + __i;
+ return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
+}
+
+template <class _Tp, class _Allocator>
+inline typename deque<_Tp, _Allocator>::const_reference deque<_Tp, _Allocator>::at(size_type __i) const {
+ if (__i >= size())
+ std::__throw_out_of_range("deque");
+ size_type __p = __start_ + __i;
+ return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
+}
+
+template <class _Tp, class _Allocator>
+inline typename deque<_Tp, _Allocator>::reference deque<_Tp, _Allocator>::front() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "deque::front called on an empty deque");
+ return *(*(__map_.begin() + __start_ / __block_size) + __start_ % __block_size);
+}
+
+template <class _Tp, class _Allocator>
+inline typename deque<_Tp, _Allocator>::const_reference deque<_Tp, _Allocator>::front() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "deque::front called on an empty deque");
+ return *(*(__map_.begin() + __start_ / __block_size) + __start_ % __block_size);
+}
+
+template <class _Tp, class _Allocator>
+inline typename deque<_Tp, _Allocator>::reference deque<_Tp, _Allocator>::back() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "deque::back called on an empty deque");
+ size_type __p = size() + __start_ - 1;
+ return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
+}
+
+template <class _Tp, class _Allocator>
+inline typename deque<_Tp, _Allocator>::const_reference deque<_Tp, _Allocator>::back() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "deque::back called on an empty deque");
+ size_type __p = size() + __start_ - 1;
+ return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::push_back(const value_type& __v) {
+ allocator_type& __a = __alloc();
+ if (__back_spare() == 0)
+ __add_back_capacity();
+ // __back_spare() >= 1
+ __annotate_increase_back(1);
+ __alloc_traits::construct(__a, std::addressof(*end()), __v);
+ ++__size();
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::push_front(const value_type& __v) {
+ allocator_type& __a = __alloc();
+ if (__front_spare() == 0)
+ __add_front_capacity();
+ // __front_spare() >= 1
+ __annotate_increase_front(1);
+ __alloc_traits::construct(__a, std::addressof(*--begin()), __v);
+ --__start_;
+ ++__size();
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::push_back(value_type&& __v) {
+ allocator_type& __a = __alloc();
+ if (__back_spare() == 0)
+ __add_back_capacity();
+ // __back_spare() >= 1
+ __annotate_increase_back(1);
+ __alloc_traits::construct(__a, std::addressof(*end()), std::move(__v));
+ ++__size();
+}
+
+template <class _Tp, class _Allocator>
+template <class... _Args>
+# if _LIBCPP_STD_VER >= 17
+typename deque<_Tp, _Allocator>::reference
+# else
+void
+# endif
+deque<_Tp, _Allocator>::emplace_back(_Args&&... __args) {
+ allocator_type& __a = __alloc();
+ if (__back_spare() == 0)
+ __add_back_capacity();
+ // __back_spare() >= 1
+ __annotate_increase_back(1);
+ __alloc_traits::construct(__a, std::addressof(*end()), std::forward<_Args>(__args)...);
+ ++__size();
+# if _LIBCPP_STD_VER >= 17
+ return *--end();
+# endif
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::push_front(value_type&& __v) {
+ allocator_type& __a = __alloc();
+ if (__front_spare() == 0)
+ __add_front_capacity();
+ // __front_spare() >= 1
+ __annotate_increase_front(1);
+ __alloc_traits::construct(__a, std::addressof(*--begin()), std::move(__v));
+ --__start_;
+ ++__size();
+}
+
+template <class _Tp, class _Allocator>
+template <class... _Args>
+# if _LIBCPP_STD_VER >= 17
+typename deque<_Tp, _Allocator>::reference
+# else
+void
+# endif
+deque<_Tp, _Allocator>::emplace_front(_Args&&... __args) {
+ allocator_type& __a = __alloc();
+ if (__front_spare() == 0)
+ __add_front_capacity();
+ // __front_spare() >= 1
+ __annotate_increase_front(1);
+ __alloc_traits::construct(__a, std::addressof(*--begin()), std::forward<_Args>(__args)...);
+ --__start_;
+ ++__size();
+# if _LIBCPP_STD_VER >= 17
+ return *begin();
+# endif
+}
+
+template <class _Tp, class _Allocator>
+typename deque<_Tp, _Allocator>::iterator deque<_Tp, _Allocator>::insert(const_iterator __p, value_type&& __v) {
+ size_type __pos = __p - begin();
+ size_type __to_end = size() - __pos;
+ allocator_type& __a = __alloc();
+ if (__pos < __to_end) { // insert by shifting things backward
+ if (__front_spare() == 0)
+ __add_front_capacity();
+ // __front_spare() >= 1
+ __annotate_increase_front(1);
+ if (__pos == 0) {
+ __alloc_traits::construct(__a, std::addressof(*--begin()), std::move(__v));
+ --__start_;
+ ++__size();
+ } else {
+ iterator __b = begin();
+ iterator __bm1 = std::prev(__b);
+ __alloc_traits::construct(__a, std::addressof(*__bm1), std::move(*__b));
+ --__start_;
+ ++__size();
+ if (__pos > 1)
+ __b = std::move(std::next(__b), __b + __pos, __b);
+ *__b = std::move(__v);
+ }
+ } else { // insert by shifting things forward
+ if (__back_spare() == 0)
+ __add_back_capacity();
+ // __back_capacity >= 1
+ __annotate_increase_back(1);
+ size_type __de = size() - __pos;
+ if (__de == 0) {
+ __alloc_traits::construct(__a, std::addressof(*end()), std::move(__v));
+ ++__size();
+ } else {
+ iterator __e = end();
+ iterator __em1 = std::prev(__e);
+ __alloc_traits::construct(__a, std::addressof(*__e), std::move(*__em1));
+ ++__size();
+ if (__de > 1)
+ __e = std::move_backward(__e - __de, __em1, __e);
+ *--__e = std::move(__v);
+ }
+ }
+ return begin() + __pos;
+}
+
+template <class _Tp, class _Allocator>
+template <class... _Args>
+typename deque<_Tp, _Allocator>::iterator deque<_Tp, _Allocator>::emplace(const_iterator __p, _Args&&... __args) {
+ size_type __pos = __p - begin();
+ size_type __to_end = size() - __pos;
+ allocator_type& __a = __alloc();
+ if (__pos < __to_end) { // insert by shifting things backward
+ if (__front_spare() == 0)
+ __add_front_capacity();
+ // __front_spare() >= 1
+ __annotate_increase_front(1);
+ if (__pos == 0) {
+ __alloc_traits::construct(__a, std::addressof(*--begin()), std::forward<_Args>(__args)...);
+ --__start_;
+ ++__size();
+ } else {
+ __temp_value<value_type, _Allocator> __tmp(__alloc(), std::forward<_Args>(__args)...);
+ iterator __b = begin();
+ iterator __bm1 = std::prev(__b);
+ __alloc_traits::construct(__a, std::addressof(*__bm1), std::move(*__b));
+ --__start_;
+ ++__size();
+ if (__pos > 1)
+ __b = std::move(std::next(__b), __b + __pos, __b);
+ *__b = std::move(__tmp.get());
+ }
+ } else { // insert by shifting things forward
+ if (__back_spare() == 0)
+ __add_back_capacity();
+ // __back_capacity >= 1
+ __annotate_increase_back(1);
+ size_type __de = size() - __pos;
+ if (__de == 0) {
+ __alloc_traits::construct(__a, std::addressof(*end()), std::forward<_Args>(__args)...);
+ ++__size();
+ } else {
+ __temp_value<value_type, _Allocator> __tmp(__alloc(), std::forward<_Args>(__args)...);
+ iterator __e = end();
+ iterator __em1 = std::prev(__e);
+ __alloc_traits::construct(__a, std::addressof(*__e), std::move(*__em1));
+ ++__size();
+ if (__de > 1)
+ __e = std::move_backward(__e - __de, __em1, __e);
+ *--__e = std::move(__tmp.get());
+ }
+ }
+ return begin() + __pos;
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Allocator>
+typename deque<_Tp, _Allocator>::iterator deque<_Tp, _Allocator>::insert(const_iterator __p, const value_type& __v) {
+ size_type __pos = __p - begin();
+ size_type __to_end = size() - __pos;
+ allocator_type& __a = __alloc();
+ if (__pos < __to_end) { // insert by shifting things backward
+ if (__front_spare() == 0)
+ __add_front_capacity();
+ // __front_spare() >= 1
+ __annotate_increase_front(1);
+ if (__pos == 0) {
+ __alloc_traits::construct(__a, std::addressof(*--begin()), __v);
+ --__start_;
+ ++__size();
+ } else {
+ const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
+ iterator __b = begin();
+ iterator __bm1 = std::prev(__b);
+ if (__vt == pointer_traits<const_pointer>::pointer_to(*__b))
+ __vt = pointer_traits<const_pointer>::pointer_to(*__bm1);
+ __alloc_traits::construct(__a, std::addressof(*__bm1), std::move(*__b));
+ --__start_;
+ ++__size();
+ if (__pos > 1)
+ __b = __move_and_check(std::next(__b), __b + __pos, __b, __vt);
+ *__b = *__vt;
+ }
+ } else { // insert by shifting things forward
+ if (__back_spare() == 0)
+ __add_back_capacity();
+ // __back_capacity >= 1
+ __annotate_increase_back(1);
+ size_type __de = size() - __pos;
+ if (__de == 0) {
+ __alloc_traits::construct(__a, std::addressof(*end()), __v);
+ ++__size();
+ } else {
+ const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
+ iterator __e = end();
+ iterator __em1 = std::prev(__e);
+ if (__vt == pointer_traits<const_pointer>::pointer_to(*__em1))
+ __vt = pointer_traits<const_pointer>::pointer_to(*__e);
+ __alloc_traits::construct(__a, std::addressof(*__e), std::move(*__em1));
+ ++__size();
+ if (__de > 1)
+ __e = __move_backward_and_check(__e - __de, __em1, __e, __vt);
+ *--__e = *__vt;
+ }
+ }
+ return begin() + __pos;
+}
+
+template <class _Tp, class _Allocator>
+typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::insert(const_iterator __p, size_type __n, const value_type& __v) {
+ size_type __pos = __p - begin();
+ size_type __to_end = __size() - __pos;
+ allocator_type& __a = __alloc();
+ if (__pos < __to_end) { // insert by shifting things backward
+ if (__n > __front_spare())
+ __add_front_capacity(__n - __front_spare());
+ // __n <= __front_spare()
+ __annotate_increase_front(__n);
+ iterator __old_begin = begin();
+ iterator __i = __old_begin;
+ if (__n > __pos) {
+ for (size_type __m = __n - __pos; __m; --__m, --__start_, ++__size())
+ __alloc_traits::construct(__a, std::addressof(*--__i), __v);
+ __n = __pos;
+ }
+ if (__n > 0) {
+ const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
+ iterator __obn = __old_begin + __n;
+ __move_construct_backward_and_check(__old_begin, __obn, __i, __vt);
+ if (__n < __pos)
+ __old_begin = __move_and_check(__obn, __old_begin + __pos, __old_begin, __vt);
+ std::fill_n(__old_begin, __n, *__vt);
+ }
+ } else { // insert by shifting things forward
+ size_type __back_capacity = __back_spare();
+ if (__n > __back_capacity)
+ __add_back_capacity(__n - __back_capacity);
+ // __n <= __back_capacity
+ __annotate_increase_back(__n);
+ iterator __old_end = end();
+ iterator __i = __old_end;
+ size_type __de = size() - __pos;
+ if (__n > __de) {
+ for (size_type __m = __n - __de; __m; --__m, (void)++__i, ++__size())
+ __alloc_traits::construct(__a, std::addressof(*__i), __v);
+ __n = __de;
+ }
+ if (__n > 0) {
+ const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
+ iterator __oen = __old_end - __n;
+ __move_construct_and_check(__oen, __old_end, __i, __vt);
+ if (__n < __de)
+ __old_end = __move_backward_and_check(__old_end - __de, __oen, __old_end, __vt);
+ std::fill_n(__old_end - __n, __n, *__vt);
+ }
+ }
+ return begin() + __pos;
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIter, __enable_if_t<__has_exactly_input_iterator_category<_InputIter>::value, int> >
+typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::insert(const_iterator __p, _InputIter __f, _InputIter __l) {
+ return __insert_with_sentinel(__p, __f, __l);
+}
+
+template <class _Tp, class _Allocator>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::__insert_with_sentinel(const_iterator __p, _Iterator __f, _Sentinel __l) {
+ __split_buffer<value_type, allocator_type&> __buf(__alloc());
+ __buf.__construct_at_end_with_sentinel(std::move(__f), std::move(__l));
+ typedef typename __split_buffer<value_type, allocator_type&>::iterator __bi;
+ return insert(__p, move_iterator<__bi>(__buf.begin()), move_iterator<__bi>(__buf.end()));
+}
+
+template <class _Tp, class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_exactly_forward_iterator_category<_ForwardIterator>::value, int> >
+typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::insert(const_iterator __p, _ForwardIterator __f, _ForwardIterator __l) {
+ return __insert_with_size(__p, __f, std::distance(__f, __l));
+}
+
+template <class _Tp, class _Allocator>
+template <class _Iterator>
+_LIBCPP_HIDE_FROM_ABI typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::__insert_with_size(const_iterator __p, _Iterator __f, size_type __n) {
+ __split_buffer<value_type, allocator_type&> __buf(__n, 0, __alloc());
+ __buf.__construct_at_end_with_size(__f, __n);
+ typedef typename __split_buffer<value_type, allocator_type&>::iterator __fwd;
+ return insert(__p, move_iterator<__fwd>(__buf.begin()), move_iterator<__fwd>(__buf.end()));
+}
+
+template <class _Tp, class _Allocator>
+template <class _BiIter, __enable_if_t<__has_bidirectional_iterator_category<_BiIter>::value, int> >
+typename deque<_Tp, _Allocator>::iterator deque<_Tp, _Allocator>::insert(const_iterator __p, _BiIter __f, _BiIter __l) {
+ return __insert_bidirectional(__p, __f, __l, std::distance(__f, __l));
+}
+
+template <class _Tp, class _Allocator>
+template <class _BiIter, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::__insert_bidirectional(const_iterator __p, _BiIter __f, _Sentinel, size_type __n) {
+ return __insert_bidirectional(__p, __f, std::next(__f, __n), __n);
+}
+
+template <class _Tp, class _Allocator>
+template <class _BiIter>
+_LIBCPP_HIDE_FROM_ABI typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::__insert_bidirectional(const_iterator __p, _BiIter __f, _BiIter __l, size_type __n) {
+ size_type __pos = __p - begin();
+ size_type __to_end = size() - __pos;
+ allocator_type& __a = __alloc();
+ if (__pos < __to_end) { // insert by shifting things backward
+ if (__n > __front_spare())
+ __add_front_capacity(__n - __front_spare());
+ // __n <= __front_spare()
+ __annotate_increase_front(__n);
+ iterator __old_begin = begin();
+ iterator __i = __old_begin;
+ _BiIter __m = __f;
+ if (__n > __pos) {
+ __m = __pos < __n / 2 ? std::prev(__l, __pos) : std::next(__f, __n - __pos);
+ for (_BiIter __j = __m; __j != __f; --__start_, ++__size())
+ __alloc_traits::construct(__a, std::addressof(*--__i), *--__j);
+ __n = __pos;
+ }
+ if (__n > 0) {
+ iterator __obn = __old_begin + __n;
+ for (iterator __j = __obn; __j != __old_begin;) {
+ __alloc_traits::construct(__a, std::addressof(*--__i), std::move(*--__j));
+ --__start_;
+ ++__size();
+ }
+ if (__n < __pos)
+ __old_begin = std::move(__obn, __old_begin + __pos, __old_begin);
+ std::copy(__m, __l, __old_begin);
+ }
+ } else { // insert by shifting things forward
+ size_type __back_capacity = __back_spare();
+ if (__n > __back_capacity)
+ __add_back_capacity(__n - __back_capacity);
+ // __n <= __back_capacity
+ __annotate_increase_back(__n);
+ iterator __old_end = end();
+ iterator __i = __old_end;
+ _BiIter __m = __l;
+ size_type __de = size() - __pos;
+ if (__n > __de) {
+ __m = __de < __n / 2 ? std::next(__f, __de) : std::prev(__l, __n - __de);
+ for (_BiIter __j = __m; __j != __l; ++__i, (void)++__j, ++__size())
+ __alloc_traits::construct(__a, std::addressof(*__i), *__j);
+ __n = __de;
+ }
+ if (__n > 0) {
+ iterator __oen = __old_end - __n;
+ for (iterator __j = __oen; __j != __old_end; ++__i, (void)++__j, ++__size())
+ __alloc_traits::construct(__a, std::addressof(*__i), std::move(*__j));
+ if (__n < __de)
+ __old_end = std::move_backward(__old_end - __de, __oen, __old_end);
+ std::copy_backward(__f, __m, __old_end);
+ }
+ }
+ return begin() + __pos;
+}
+
+template <class _Tp, class _Allocator>
+template <class _InpIter, __enable_if_t<__has_exactly_input_iterator_category<_InpIter>::value, int> >
+void deque<_Tp, _Allocator>::__append(_InpIter __f, _InpIter __l) {
+ __append_with_sentinel(__f, __l);
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI void deque<_Tp, _Allocator>::__append_with_sentinel(_InputIterator __f, _Sentinel __l) {
+ for (; __f != __l; ++__f)
+#ifdef _LIBCPP_CXX03_LANG
+ push_back(*__f);
+#else
+ emplace_back(*__f);
+#endif
+}
+
+template <class _Tp, class _Allocator>
+template <class _ForIter, __enable_if_t<__has_forward_iterator_category<_ForIter>::value, int> >
+void deque<_Tp, _Allocator>::__append(_ForIter __f, _ForIter __l) {
+ __append_with_size(__f, std::distance(__f, __l));
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIterator>
+_LIBCPP_HIDE_FROM_ABI void deque<_Tp, _Allocator>::__append_with_size(_InputIterator __f, size_type __n) {
+ allocator_type& __a = __alloc();
+ size_type __back_capacity = __back_spare();
+ if (__n > __back_capacity)
+ __add_back_capacity(__n - __back_capacity);
+
+ // __n <= __back_capacity
+ __annotate_increase_back(__n);
+ for (__deque_block_range __br : __deque_range(end(), end() + __n)) {
+ _ConstructTransaction __tx(this, __br);
+ for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_, (void)++__f) {
+ __alloc_traits::construct(__a, std::__to_address(__tx.__pos_), *__f);
+ }
+ }
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__append(size_type __n) {
+ allocator_type& __a = __alloc();
+ size_type __back_capacity = __back_spare();
+ if (__n > __back_capacity)
+ __add_back_capacity(__n - __back_capacity);
+ // __n <= __back_capacity
+ __annotate_increase_back(__n);
+ for (__deque_block_range __br : __deque_range(end(), end() + __n)) {
+ _ConstructTransaction __tx(this, __br);
+ for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
+ __alloc_traits::construct(__a, std::__to_address(__tx.__pos_));
+ }
+ }
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__append(size_type __n, const value_type& __v) {
+ allocator_type& __a = __alloc();
+ size_type __back_capacity = __back_spare();
+ if (__n > __back_capacity)
+ __add_back_capacity(__n - __back_capacity);
+ // __n <= __back_capacity
+ __annotate_increase_back(__n);
+ for (__deque_block_range __br : __deque_range(end(), end() + __n)) {
+ _ConstructTransaction __tx(this, __br);
+ for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
+ __alloc_traits::construct(__a, std::__to_address(__tx.__pos_), __v);
+ }
+ }
+}
+
+// Create front capacity for one block of elements.
+// Strong guarantee. Either do it or don't touch anything.
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__add_front_capacity() {
+ allocator_type& __a = __alloc();
+ if (__back_spare() >= __block_size) {
+ __start_ += __block_size;
+ pointer __pt = __map_.back();
+ __map_.pop_back();
+ __map_.push_front(__pt);
+ }
+ // Else if __map_.size() < __map_.capacity() then we need to allocate 1 buffer
+ else if (__map_.size() < __map_.capacity()) { // we can put the new buffer into the map, but don't shift things around
+ // until all buffers are allocated. If we throw, we don't need to fix
+ // anything up (any added buffers are undetectible)
+ if (__map_.__front_spare() > 0)
+ __map_.push_front(__alloc_traits::allocate(__a, __block_size));
+ else {
+ __map_.push_back(__alloc_traits::allocate(__a, __block_size));
+ // Done allocating, reorder capacity
+ pointer __pt = __map_.back();
+ __map_.pop_back();
+ __map_.push_front(__pt);
+ }
+ __start_ = __map_.size() == 1 ? __block_size / 2 : __start_ + __block_size;
+ }
+ // Else need to allocate 1 buffer, *and* we need to reallocate __map_.
+ else {
+ __split_buffer<pointer, __pointer_allocator&> __buf(
+ std::max<size_type>(2 * __map_.capacity(), 1), 0, __map_.__alloc());
+
+ typedef __allocator_destructor<_Allocator> _Dp;
+ unique_ptr<pointer, _Dp> __hold(__alloc_traits::allocate(__a, __block_size), _Dp(__a, __block_size));
+ __buf.push_back(__hold.get());
+ __hold.release();
+
+ for (__map_pointer __i = __map_.begin(); __i != __map_.end(); ++__i)
+ __buf.push_back(*__i);
+ std::swap(__map_.__first_, __buf.__first_);
+ std::swap(__map_.__begin_, __buf.__begin_);
+ std::swap(__map_.__end_, __buf.__end_);
+ std::swap(__map_.__end_cap(), __buf.__end_cap());
+ __start_ = __map_.size() == 1 ? __block_size / 2 : __start_ + __block_size;
+ }
+ __annotate_whole_block(0, __asan_poison);
+}
+
+// Create front capacity for __n elements.
+// Strong guarantee. Either do it or don't touch anything.
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__add_front_capacity(size_type __n) {
+ allocator_type& __a = __alloc();
+ size_type __nb = __recommend_blocks(__n + __map_.empty());
+ // Number of unused blocks at back:
+ size_type __back_capacity = __back_spare() / __block_size;
+ __back_capacity = std::min(__back_capacity, __nb); // don't take more than you need
+ __nb -= __back_capacity; // number of blocks need to allocate
+ // If __nb == 0, then we have sufficient capacity.
+ if (__nb == 0) {
+ __start_ += __block_size * __back_capacity;
+ for (; __back_capacity > 0; --__back_capacity) {
+ pointer __pt = __map_.back();
+ __map_.pop_back();
+ __map_.push_front(__pt);
+ }
+ }
+ // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
+ else if (__nb <= __map_.capacity() -
+ __map_.size()) { // we can put the new buffers into the map, but don't shift things around
+ // until all buffers are allocated. If we throw, we don't need to fix
+ // anything up (any added buffers are undetectible)
+ for (; __nb > 0; --__nb, __start_ += __block_size - (__map_.size() == 1)) {
+ if (__map_.__front_spare() == 0)
+ break;
+ __map_.push_front(__alloc_traits::allocate(__a, __block_size));
+ __annotate_whole_block(0, __asan_poison);
+ }
+ for (; __nb > 0; --__nb, ++__back_capacity)
+ __map_.push_back(__alloc_traits::allocate(__a, __block_size));
+ // Done allocating, reorder capacity
+ __start_ += __back_capacity * __block_size;
+ for (; __back_capacity > 0; --__back_capacity) {
+ pointer __pt = __map_.back();
+ __map_.pop_back();
+ __map_.push_front(__pt);
+ __annotate_whole_block(0, __asan_poison);
+ }
+ }
+ // Else need to allocate __nb buffers, *and* we need to reallocate __map_.
+ else {
+ size_type __ds = (__nb + __back_capacity) * __block_size - __map_.empty();
+ __split_buffer<pointer, __pointer_allocator&> __buf(
+ std::max<size_type>(2 * __map_.capacity(), __nb + __map_.size()), 0, __map_.__alloc());
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (; __nb > 0; --__nb) {
+ __buf.push_back(__alloc_traits::allocate(__a, __block_size));
+ // ASan: this is empty container, we have to poison whole block
+ __annotate_poison_block(std::__to_address(__buf.back()), std::__to_address(__buf.back() + __block_size));
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __annotate_delete();
+ for (__map_pointer __i = __buf.begin(); __i != __buf.end(); ++__i)
+ __alloc_traits::deallocate(__a, *__i, __block_size);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (; __back_capacity > 0; --__back_capacity) {
+ __buf.push_back(__map_.back());
+ __map_.pop_back();
+ }
+ for (__map_pointer __i = __map_.begin(); __i != __map_.end(); ++__i)
+ __buf.push_back(*__i);
+ std::swap(__map_.__first_, __buf.__first_);
+ std::swap(__map_.__begin_, __buf.__begin_);
+ std::swap(__map_.__end_, __buf.__end_);
+ std::swap(__map_.__end_cap(), __buf.__end_cap());
+ __start_ += __ds;
+ }
+}
+
+// Create back capacity for one block of elements.
+// Strong guarantee. Either do it or don't touch anything.
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__add_back_capacity() {
+ allocator_type& __a = __alloc();
+ if (__front_spare() >= __block_size) {
+ __start_ -= __block_size;
+ pointer __pt = __map_.front();
+ __map_.pop_front();
+ __map_.push_back(__pt);
+ }
+ // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
+ else if (__map_.size() < __map_.capacity()) { // we can put the new buffer into the map, but don't shift things around
+ // until it is allocated. If we throw, we don't need to fix
+ // anything up (any added buffers are undetectible)
+ if (__map_.__back_spare() != 0)
+ __map_.push_back(__alloc_traits::allocate(__a, __block_size));
+ else {
+ __map_.push_front(__alloc_traits::allocate(__a, __block_size));
+ // Done allocating, reorder capacity
+ pointer __pt = __map_.front();
+ __map_.pop_front();
+ __map_.push_back(__pt);
+ }
+ __annotate_whole_block(__map_.size() - 1, __asan_poison);
+ }
+ // Else need to allocate 1 buffer, *and* we need to reallocate __map_.
+ else {
+ __split_buffer<pointer, __pointer_allocator&> __buf(
+ std::max<size_type>(2 * __map_.capacity(), 1), __map_.size(), __map_.__alloc());
+
+ typedef __allocator_destructor<_Allocator> _Dp;
+ unique_ptr<pointer, _Dp> __hold(__alloc_traits::allocate(__a, __block_size), _Dp(__a, __block_size));
+ __buf.push_back(__hold.get());
+ __hold.release();
+
+ for (__map_pointer __i = __map_.end(); __i != __map_.begin();)
+ __buf.push_front(*--__i);
+ std::swap(__map_.__first_, __buf.__first_);
+ std::swap(__map_.__begin_, __buf.__begin_);
+ std::swap(__map_.__end_, __buf.__end_);
+ std::swap(__map_.__end_cap(), __buf.__end_cap());
+ __annotate_whole_block(__map_.size() - 1, __asan_poison);
+ }
+}
+
+// Create back capacity for __n elements.
+// Strong guarantee. Either do it or don't touch anything.
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__add_back_capacity(size_type __n) {
+ allocator_type& __a = __alloc();
+ size_type __nb = __recommend_blocks(__n + __map_.empty());
+ // Number of unused blocks at front:
+ size_type __front_capacity = __front_spare() / __block_size;
+ __front_capacity = std::min(__front_capacity, __nb); // don't take more than you need
+ __nb -= __front_capacity; // number of blocks need to allocate
+ // If __nb == 0, then we have sufficient capacity.
+ if (__nb == 0) {
+ __start_ -= __block_size * __front_capacity;
+ for (; __front_capacity > 0; --__front_capacity) {
+ pointer __pt = __map_.front();
+ __map_.pop_front();
+ __map_.push_back(__pt);
+ }
+ }
+ // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
+ else if (__nb <= __map_.capacity() -
+ __map_.size()) { // we can put the new buffers into the map, but don't shift things around
+ // until all buffers are allocated. If we throw, we don't need to fix
+ // anything up (any added buffers are undetectible)
+ for (; __nb > 0; --__nb) {
+ if (__map_.__back_spare() == 0)
+ break;
+ __map_.push_back(__alloc_traits::allocate(__a, __block_size));
+ __annotate_whole_block(__map_.size() - 1, __asan_poison);
+ }
+ for (; __nb > 0; --__nb, ++__front_capacity, __start_ += __block_size - (__map_.size() == 1)) {
+ __map_.push_front(__alloc_traits::allocate(__a, __block_size));
+ __annotate_whole_block(0, __asan_poison);
+ }
+ // Done allocating, reorder capacity
+ __start_ -= __block_size * __front_capacity;
+ for (; __front_capacity > 0; --__front_capacity) {
+ pointer __pt = __map_.front();
+ __map_.pop_front();
+ __map_.push_back(__pt);
+ }
+ }
+ // Else need to allocate __nb buffers, *and* we need to reallocate __map_.
+ else {
+ size_type __ds = __front_capacity * __block_size;
+ __split_buffer<pointer, __pointer_allocator&> __buf(
+ std::max<size_type>(2 * __map_.capacity(), __nb + __map_.size()),
+ __map_.size() - __front_capacity,
+ __map_.__alloc());
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (; __nb > 0; --__nb) {
+ __buf.push_back(__alloc_traits::allocate(__a, __block_size));
+ // ASan: this is an empty container, we have to poison the whole block
+ __annotate_poison_block(std::__to_address(__buf.back()), std::__to_address(__buf.back() + __block_size));
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __annotate_delete();
+ for (__map_pointer __i = __buf.begin(); __i != __buf.end(); ++__i)
+ __alloc_traits::deallocate(__a, *__i, __block_size);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (; __front_capacity > 0; --__front_capacity) {
+ __buf.push_back(__map_.front());
+ __map_.pop_front();
+ }
+ for (__map_pointer __i = __map_.end(); __i != __map_.begin();)
+ __buf.push_front(*--__i);
+ std::swap(__map_.__first_, __buf.__first_);
+ std::swap(__map_.__begin_, __buf.__begin_);
+ std::swap(__map_.__end_, __buf.__end_);
+ std::swap(__map_.__end_cap(), __buf.__end_cap());
+ __start_ -= __ds;
+ }
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::pop_front() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "deque::pop_front called on an empty deque");
+ size_type __old_sz = size();
+ size_type __old_start = __start_;
+ allocator_type& __a = __alloc();
+ __alloc_traits::destroy(
+ __a, std::__to_address(*(__map_.begin() + __start_ / __block_size) + __start_ % __block_size));
+ --__size();
+ ++__start_;
+ __annotate_shrink_front(__old_sz, __old_start);
+ __maybe_remove_front_spare();
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::pop_back() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "deque::pop_back called on an empty deque");
+ size_type __old_sz = size();
+ size_type __old_start = __start_;
+ allocator_type& __a = __alloc();
+ size_type __p = size() + __start_ - 1;
+ __alloc_traits::destroy(__a, std::__to_address(*(__map_.begin() + __p / __block_size) + __p % __block_size));
+ --__size();
+ __annotate_shrink_back(__old_sz, __old_start);
+ __maybe_remove_back_spare();
+}
+
+// move assign [__f, __l) to [__r, __r + (__l-__f)).
+// If __vt points into [__f, __l), then subtract (__f - __r) from __vt.
+template <class _Tp, class _Allocator>
+typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::__move_and_check(iterator __f, iterator __l, iterator __r, const_pointer& __vt) {
+ // as if
+ // for (; __f != __l; ++__f, ++__r)
+ // *__r = std::move(*__f);
+ difference_type __n = __l - __f;
+ while (__n > 0) {
+ pointer __fb = __f.__ptr_;
+ pointer __fe = *__f.__m_iter_ + __block_size;
+ difference_type __bs = __fe - __fb;
+ if (__bs > __n) {
+ __bs = __n;
+ __fe = __fb + __bs;
+ }
+ if (__fb <= __vt && __vt < __fe)
+ __vt = (const_iterator(static_cast<__map_const_pointer>(__f.__m_iter_), __vt) -= __f - __r).__ptr_;
+ __r = std::move(__fb, __fe, __r);
+ __n -= __bs;
+ __f += __bs;
+ }
+ return __r;
+}
+
+// move assign [__f, __l) to [__r - (__l-__f), __r) backwards.
+// If __vt points into [__f, __l), then add (__r - __l) to __vt.
+template <class _Tp, class _Allocator>
+typename deque<_Tp, _Allocator>::iterator
+deque<_Tp, _Allocator>::__move_backward_and_check(iterator __f, iterator __l, iterator __r, const_pointer& __vt) {
+ // as if
+ // while (__f != __l)
+ // *--__r = std::move(*--__l);
+ difference_type __n = __l - __f;
+ while (__n > 0) {
+ --__l;
+ pointer __lb = *__l.__m_iter_;
+ pointer __le = __l.__ptr_ + 1;
+ difference_type __bs = __le - __lb;
+ if (__bs > __n) {
+ __bs = __n;
+ __lb = __le - __bs;
+ }
+ if (__lb <= __vt && __vt < __le)
+ __vt = (const_iterator(static_cast<__map_const_pointer>(__l.__m_iter_), __vt) += __r - __l - 1).__ptr_;
+ __r = std::move_backward(__lb, __le, __r);
+ __n -= __bs;
+ __l -= __bs - 1;
+ }
+ return __r;
+}
+
+// move construct [__f, __l) to [__r, __r + (__l-__f)).
+// If __vt points into [__f, __l), then add (__r - __f) to __vt.
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__move_construct_and_check(iterator __f, iterator __l, iterator __r, const_pointer& __vt) {
+ allocator_type& __a = __alloc();
+ // as if
+ // for (; __f != __l; ++__r, ++__f, ++__size())
+ // __alloc_traits::construct(__a, std::addressof(*__r), std::move(*__f));
+ difference_type __n = __l - __f;
+ while (__n > 0) {
+ pointer __fb = __f.__ptr_;
+ pointer __fe = *__f.__m_iter_ + __block_size;
+ difference_type __bs = __fe - __fb;
+ if (__bs > __n) {
+ __bs = __n;
+ __fe = __fb + __bs;
+ }
+ if (__fb <= __vt && __vt < __fe)
+ __vt = (const_iterator(static_cast<__map_const_pointer>(__f.__m_iter_), __vt) += __r - __f).__ptr_;
+ for (; __fb != __fe; ++__fb, ++__r, ++__size())
+ __alloc_traits::construct(__a, std::addressof(*__r), std::move(*__fb));
+ __n -= __bs;
+ __f += __bs;
+ }
+}
+
+// move construct [__f, __l) to [__r - (__l-__f), __r) backwards.
+// If __vt points into [__f, __l), then subtract (__l - __r) from __vt.
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__move_construct_backward_and_check(
+ iterator __f, iterator __l, iterator __r, const_pointer& __vt) {
+ allocator_type& __a = __alloc();
+ // as if
+ // for (iterator __j = __l; __j != __f;)
+ // {
+ // __alloc_traitsconstruct(__a, std::addressof(*--__r), std::move(*--__j));
+ // --__start_;
+ // ++__size();
+ // }
+ difference_type __n = __l - __f;
+ while (__n > 0) {
+ --__l;
+ pointer __lb = *__l.__m_iter_;
+ pointer __le = __l.__ptr_ + 1;
+ difference_type __bs = __le - __lb;
+ if (__bs > __n) {
+ __bs = __n;
+ __lb = __le - __bs;
+ }
+ if (__lb <= __vt && __vt < __le)
+ __vt = (const_iterator(static_cast<__map_const_pointer>(__l.__m_iter_), __vt) -= __l - __r + 1).__ptr_;
+ while (__le != __lb) {
+ __alloc_traits::construct(__a, std::addressof(*--__r), std::move(*--__le));
+ --__start_;
+ ++__size();
+ }
+ __n -= __bs;
+ __l -= __bs - 1;
+ }
+}
+
+template <class _Tp, class _Allocator>
+typename deque<_Tp, _Allocator>::iterator deque<_Tp, _Allocator>::erase(const_iterator __f) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __f != end(), "deque::erase(iterator) called with a non-dereferenceable iterator");
+ size_type __old_sz = size();
+ size_type __old_start = __start_;
+ iterator __b = begin();
+ difference_type __pos = __f - __b;
+ iterator __p = __b + __pos;
+ allocator_type& __a = __alloc();
+ if (static_cast<size_t>(__pos) <= (size() - 1) / 2) { // erase from front
+ std::move_backward(__b, __p, std::next(__p));
+ __alloc_traits::destroy(__a, std::addressof(*__b));
+ --__size();
+ ++__start_;
+ __annotate_shrink_front(__old_sz, __old_start);
+ __maybe_remove_front_spare();
+ } else { // erase from back
+ iterator __i = std::move(std::next(__p), end(), __p);
+ __alloc_traits::destroy(__a, std::addressof(*__i));
+ --__size();
+ __annotate_shrink_back(__old_sz, __old_start);
+ __maybe_remove_back_spare();
+ }
+ return begin() + __pos;
+}
+
+template <class _Tp, class _Allocator>
+typename deque<_Tp, _Allocator>::iterator deque<_Tp, _Allocator>::erase(const_iterator __f, const_iterator __l) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__f <= __l, "deque::erase(first, last) called with an invalid range");
+ size_type __old_sz = size();
+ size_type __old_start = __start_;
+ difference_type __n = __l - __f;
+ iterator __b = begin();
+ difference_type __pos = __f - __b;
+ iterator __p = __b + __pos;
+ if (__n > 0) {
+ allocator_type& __a = __alloc();
+ if (static_cast<size_t>(__pos) <= (size() - __n) / 2) { // erase from front
+ iterator __i = std::move_backward(__b, __p, __p + __n);
+ for (; __b != __i; ++__b)
+ __alloc_traits::destroy(__a, std::addressof(*__b));
+ __size() -= __n;
+ __start_ += __n;
+ __annotate_shrink_front(__old_sz, __old_start);
+ while (__maybe_remove_front_spare()) {
+ }
+ } else { // erase from back
+ iterator __i = std::move(__p + __n, end(), __p);
+ for (iterator __e = end(); __i != __e; ++__i)
+ __alloc_traits::destroy(__a, std::addressof(*__i));
+ __size() -= __n;
+ __annotate_shrink_back(__old_sz, __old_start);
+ while (__maybe_remove_back_spare()) {
+ }
+ }
+ }
+ return begin() + __pos;
+}
+
+template <class _Tp, class _Allocator>
+void deque<_Tp, _Allocator>::__erase_to_end(const_iterator __f) {
+ size_type __old_sz = size();
+ size_type __old_start = __start_;
+ iterator __e = end();
+ difference_type __n = __e - __f;
+ if (__n > 0) {
+ allocator_type& __a = __alloc();
+ iterator __b = begin();
+ difference_type __pos = __f - __b;
+ for (iterator __p = __b + __pos; __p != __e; ++__p)
+ __alloc_traits::destroy(__a, std::addressof(*__p));
+ __size() -= __n;
+ __annotate_shrink_back(__old_sz, __old_start);
+ while (__maybe_remove_back_spare()) {
+ }
+ }
+}
+
+template <class _Tp, class _Allocator>
+inline void deque<_Tp, _Allocator>::swap(deque& __c)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>)
+#endif
+{
+ __map_.swap(__c.__map_);
+ std::swap(__start_, __c.__start_);
+ std::swap(__size(), __c.__size());
+ std::__swap_allocator(__alloc(), __c.__alloc());
+}
+
+template <class _Tp, class _Allocator>
+inline void deque<_Tp, _Allocator>::clear() _NOEXCEPT {
+ __annotate_delete();
+ allocator_type& __a = __alloc();
+ for (iterator __i = begin(), __e = end(); __i != __e; ++__i)
+ __alloc_traits::destroy(__a, std::addressof(*__i));
+ __size() = 0;
+ while (__map_.size() > 2) {
+ __alloc_traits::deallocate(__a, __map_.front(), __block_size);
+ __map_.pop_front();
+ }
+ switch (__map_.size()) {
+ case 1:
+ __start_ = __block_size / 2;
+ break;
+ case 2:
+ __start_ = __block_size;
+ break;
+ }
+ __annotate_new(0);
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y) {
+ const typename deque<_Tp, _Allocator>::size_type __sz = __x.size();
+ return __sz == __y.size() && std::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y) {
+ return __y < __x;
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y) {
+ return !(__y < __x);
+}
+
+#else // _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __synth_three_way_result<_Tp>
+operator<=>(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y) {
+ return std::lexicographical_compare_three_way(__x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void swap(deque<_Tp, _Allocator>& __x, deque<_Tp, _Allocator>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Allocator, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI typename deque<_Tp, _Allocator>::size_type
+erase(deque<_Tp, _Allocator>& __c, const _Up& __v) {
+ auto __old_size = __c.size();
+ __c.erase(std::remove(__c.begin(), __c.end(), __v), __c.end());
+ return __old_size - __c.size();
+}
+
+template <class _Tp, class _Allocator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename deque<_Tp, _Allocator>::size_type
+erase_if(deque<_Tp, _Allocator>& __c, _Predicate __pred) {
+ auto __old_size = __c.size();
+ __c.erase(std::remove_if(__c.begin(), __c.end(), __pred), __c.end());
+ return __old_size - __c.size();
+}
+
+template <>
+inline constexpr bool __format::__enable_insertable<std::deque<char>> = true;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+inline constexpr bool __format::__enable_insertable<std::deque<wchar_t>> = true;
+# endif
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _ValueT>
+using deque _LIBCPP_AVAILABILITY_PMR = std::deque<_ValueT, polymorphic_allocator<_ValueT>>;
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <atomic>
+# include <concepts>
+# include <cstdlib>
+# include <functional>
+# include <iosfwd>
+# include <iterator>
+# include <type_traits>
+# include <typeinfo>
+#endif
+
+#endif // _LIBCPP_DEQUE
diff --git a/libcxx/include/__cxx03/errno.h b/libcxx/include/__cxx03/errno.h
new file mode 100644
index 00000000000000..e657ad84ff44bb
--- /dev/null
+++ b/libcxx/include/__cxx03/errno.h
@@ -0,0 +1,399 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_ERRNO_H
+#define _LIBCPP_ERRNO_H
+
+/*
+ errno.h synopsis
+
+Macros:
+
+ EDOM
+ EILSEQ // C99
+ ERANGE
+ errno
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if __has_include_next(<errno.h>)
+# include_next <errno.h>
+#endif
+
+#ifdef __cplusplus
+
+# if !defined(EOWNERDEAD) || !defined(ENOTRECOVERABLE)
+
+# ifdef ELAST
+
+static const int __elast1 = ELAST + 1;
+static const int __elast2 = ELAST + 2;
+
+# else
+
+static const int __elast1 = 104;
+static const int __elast2 = 105;
+
+# endif
+
+# ifdef ENOTRECOVERABLE
+
+# define EOWNERDEAD __elast1
+
+# ifdef ELAST
+# undef ELAST
+# define ELAST EOWNERDEAD
+# endif
+
+# elif defined(EOWNERDEAD)
+
+# define ENOTRECOVERABLE __elast1
+# ifdef ELAST
+# undef ELAST
+# define ELAST ENOTRECOVERABLE
+# endif
+
+# else // defined(EOWNERDEAD)
+
+# define EOWNERDEAD __elast1
+# define ENOTRECOVERABLE __elast2
+# ifdef ELAST
+# undef ELAST
+# define ELAST ENOTRECOVERABLE
+# endif
+
+# endif // defined(EOWNERDEAD)
+
+# endif // !defined(EOWNERDEAD) || !defined(ENOTRECOVERABLE)
+
+// supply errno values likely to be missing, particularly on Windows
+
+# ifndef EAFNOSUPPORT
+# define EAFNOSUPPORT 9901
+# endif
+
+# ifndef EADDRINUSE
+# define EADDRINUSE 9902
+# endif
+
+# ifndef EADDRNOTAVAIL
+# define EADDRNOTAVAIL 9903
+# endif
+
+# ifndef EISCONN
+# define EISCONN 9904
+# endif
+
+# ifndef EBADMSG
+# define EBADMSG 9905
+# endif
+
+# ifndef ECONNABORTED
+# define ECONNABORTED 9906
+# endif
+
+# ifndef EALREADY
+# define EALREADY 9907
+# endif
+
+# ifndef ECONNREFUSED
+# define ECONNREFUSED 9908
+# endif
+
+# ifndef ECONNRESET
+# define ECONNRESET 9909
+# endif
+
+# ifndef EDESTADDRREQ
+# define EDESTADDRREQ 9910
+# endif
+
+# ifndef EHOSTUNREACH
+# define EHOSTUNREACH 9911
+# endif
+
+# ifndef EIDRM
+# define EIDRM 9912
+# endif
+
+# ifndef EMSGSIZE
+# define EMSGSIZE 9913
+# endif
+
+# ifndef ENETDOWN
+# define ENETDOWN 9914
+# endif
+
+# ifndef ENETRESET
+# define ENETRESET 9915
+# endif
+
+# ifndef ENETUNREACH
+# define ENETUNREACH 9916
+# endif
+
+# ifndef ENOBUFS
+# define ENOBUFS 9917
+# endif
+
+# ifndef ENOLINK
+# define ENOLINK 9918
+# endif
+
+# ifndef ENODATA
+# define ENODATA 9919
+# endif
+
+# ifndef ENOMSG
+# define ENOMSG 9920
+# endif
+
+# ifndef ENOPROTOOPT
+# define ENOPROTOOPT 9921
+# endif
+
+# ifndef ENOSR
+# define ENOSR 9922
+# endif
+
+# ifndef ENOTSOCK
+# define ENOTSOCK 9923
+# endif
+
+# ifndef ENOSTR
+# define ENOSTR 9924
+# endif
+
+# ifndef ENOTCONN
+# define ENOTCONN 9925
+# endif
+
+# ifndef ENOTSUP
+# define ENOTSUP 9926
+# endif
+
+# ifndef ECANCELED
+# define ECANCELED 9927
+# endif
+
+# ifndef EINPROGRESS
+# define EINPROGRESS 9928
+# endif
+
+# ifndef EOPNOTSUPP
+# define EOPNOTSUPP 9929
+# endif
+
+# ifndef EWOULDBLOCK
+# define EWOULDBLOCK 9930
+# endif
+
+# ifndef EOWNERDEAD
+# define EOWNERDEAD 9931
+# endif
+
+# ifndef EPROTO
+# define EPROTO 9932
+# endif
+
+# ifndef EPROTONOSUPPORT
+# define EPROTONOSUPPORT 9933
+# endif
+
+# ifndef ENOTRECOVERABLE
+# define ENOTRECOVERABLE 9934
+# endif
+
+# ifndef ETIME
+# define ETIME 9935
+# endif
+
+# ifndef ETXTBSY
+# define ETXTBSY 9936
+# endif
+
+# ifndef ETIMEDOUT
+# define ETIMEDOUT 9938
+# endif
+
+# ifndef ELOOP
+# define ELOOP 9939
+# endif
+
+# ifndef EOVERFLOW
+# define EOVERFLOW 9940
+# endif
+
+# ifndef EPROTOTYPE
+# define EPROTOTYPE 9941
+# endif
+
+# ifndef ENOSYS
+# define ENOSYS 9942
+# endif
+
+# ifndef EINVAL
+# define EINVAL 9943
+# endif
+
+# ifndef ERANGE
+# define ERANGE 9944
+# endif
+
+# ifndef EILSEQ
+# define EILSEQ 9945
+# endif
+
+// Windows Mobile doesn't appear to define these:
+
+# ifndef E2BIG
+# define E2BIG 9946
+# endif
+
+# ifndef EDOM
+# define EDOM 9947
+# endif
+
+# ifndef EFAULT
+# define EFAULT 9948
+# endif
+
+# ifndef EBADF
+# define EBADF 9949
+# endif
+
+# ifndef EPIPE
+# define EPIPE 9950
+# endif
+
+# ifndef EXDEV
+# define EXDEV 9951
+# endif
+
+# ifndef EBUSY
+# define EBUSY 9952
+# endif
+
+# ifndef ENOTEMPTY
+# define ENOTEMPTY 9953
+# endif
+
+# ifndef ENOEXEC
+# define ENOEXEC 9954
+# endif
+
+# ifndef EEXIST
+# define EEXIST 9955
+# endif
+
+# ifndef EFBIG
+# define EFBIG 9956
+# endif
+
+# ifndef ENAMETOOLONG
+# define ENAMETOOLONG 9957
+# endif
+
+# ifndef ENOTTY
+# define ENOTTY 9958
+# endif
+
+# ifndef EINTR
+# define EINTR 9959
+# endif
+
+# ifndef ESPIPE
+# define ESPIPE 9960
+# endif
+
+# ifndef EIO
+# define EIO 9961
+# endif
+
+# ifndef EISDIR
+# define EISDIR 9962
+# endif
+
+# ifndef ECHILD
+# define ECHILD 9963
+# endif
+
+# ifndef ENOLCK
+# define ENOLCK 9964
+# endif
+
+# ifndef ENOSPC
+# define ENOSPC 9965
+# endif
+
+# ifndef ENXIO
+# define ENXIO 9966
+# endif
+
+# ifndef ENODEV
+# define ENODEV 9967
+# endif
+
+# ifndef ENOENT
+# define ENOENT 9968
+# endif
+
+# ifndef ESRCH
+# define ESRCH 9969
+# endif
+
+# ifndef ENOTDIR
+# define ENOTDIR 9970
+# endif
+
+# ifndef ENOMEM
+# define ENOMEM 9971
+# endif
+
+# ifndef EPERM
+# define EPERM 9972
+# endif
+
+# ifndef EACCES
+# define EACCES 9973
+# endif
+
+# ifndef EROFS
+# define EROFS 9974
+# endif
+
+# ifndef EDEADLK
+# define EDEADLK 9975
+# endif
+
+# ifndef EAGAIN
+# define EAGAIN 9976
+# endif
+
+# ifndef ENFILE
+# define ENFILE 9977
+# endif
+
+# ifndef EMFILE
+# define EMFILE 9978
+# endif
+
+# ifndef EMLINK
+# define EMLINK 9979
+# endif
+
+#endif // __cplusplus
+
+#endif // _LIBCPP_ERRNO_H
diff --git a/libcxx/include/__cxx03/exception b/libcxx/include/__cxx03/exception
new file mode 100644
index 00000000000000..5eff8e3f8a4bfa
--- /dev/null
+++ b/libcxx/include/__cxx03/exception
@@ -0,0 +1,96 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXCEPTION
+#define _LIBCPP_EXCEPTION
+
+/*
+ exception synopsis
+
+namespace std
+{
+
+class exception
+{
+public:
+ exception() noexcept;
+ exception(const exception&) noexcept;
+ exception& operator=(const exception&) noexcept;
+ virtual ~exception() noexcept;
+ virtual const char* what() const noexcept;
+};
+
+class bad_exception
+ : public exception
+{
+public:
+ bad_exception() noexcept;
+ bad_exception(const bad_exception&) noexcept;
+ bad_exception& operator=(const bad_exception&) noexcept;
+ virtual ~bad_exception() noexcept;
+ virtual const char* what() const noexcept;
+};
+
+typedef void (*unexpected_handler)();
+unexpected_handler set_unexpected(unexpected_handler f ) noexcept;
+unexpected_handler get_unexpected() noexcept;
+[[noreturn]] void unexpected();
+
+typedef void (*terminate_handler)();
+terminate_handler set_terminate(terminate_handler f ) noexcept;
+terminate_handler get_terminate() noexcept;
+[[noreturn]] void terminate() noexcept;
+
+bool uncaught_exception() noexcept;
+int uncaught_exceptions() noexcept; // C++17
+
+typedef unspecified exception_ptr;
+
+exception_ptr current_exception() noexcept;
+void rethrow_exception [[noreturn]] (exception_ptr p);
+template<class E> exception_ptr make_exception_ptr(E e) noexcept;
+
+class nested_exception
+{
+public:
+ nested_exception() noexcept;
+ nested_exception(const nested_exception&) noexcept = default;
+ nested_exception& operator=(const nested_exception&) noexcept = default;
+ virtual ~nested_exception() = default;
+
+ // access functions
+ [[noreturn]] void rethrow_nested() const;
+ exception_ptr nested_ptr() const noexcept;
+};
+
+template <class T> [[noreturn]] void throw_with_nested(T&& t);
+template <class E> void rethrow_if_nested(const E& e);
+
+} // std
+
+*/
+
+#include <__config>
+#include <__exception/exception.h>
+#include <__exception/exception_ptr.h>
+#include <__exception/nested_exception.h>
+#include <__exception/operations.h>
+#include <__exception/terminate.h>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdlib>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_EXCEPTION
diff --git a/libcxx/include/__cxx03/execution b/libcxx/include/__cxx03/execution
new file mode 100644
index 00000000000000..94d434b2e4603e
--- /dev/null
+++ b/libcxx/include/__cxx03/execution
@@ -0,0 +1,149 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXECUTION
+#define _LIBCPP_EXECUTION
+
+/*
+namespace std::execution {
+ struct sequenced_policy;
+ struct parallel_policy;
+ struct parallel_unsequenced_policy;
+ struct unsequenced_policy; // since C++20
+
+ inline constexpr sequenced_policy seq = implementation-defined;
+ inline constexpr parallel_policy par = implementation-defined;
+ inline constexpr parallel_unsequenced_policy par_unseq = implementation-defined;
+ inline constexpr unsequenced_policy unseq = implementation-defined; // since C++20
+}
+
+namespace std {
+ template <class T>
+ struct is_execution_policy;
+
+ template <class T>
+ inline constexpr bool is_execution_policy_v;
+}
+*/
+
+#include <__config>
+#include <__type_traits/is_execution_policy.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cvref.h>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace execution {
+struct sequenced_policy {
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit sequenced_policy(__disable_user_instantiations_tag) {}
+ sequenced_policy(const sequenced_policy&) = delete;
+ sequenced_policy& operator=(const sequenced_policy&) = delete;
+};
+
+inline constexpr sequenced_policy seq{__disable_user_instantiations_tag{}};
+
+struct parallel_policy {
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit parallel_policy(__disable_user_instantiations_tag) {}
+ parallel_policy(const parallel_policy&) = delete;
+ parallel_policy& operator=(const parallel_policy&) = delete;
+};
+
+inline constexpr parallel_policy par{__disable_user_instantiations_tag{}};
+
+struct parallel_unsequenced_policy {
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit parallel_unsequenced_policy(__disable_user_instantiations_tag) {}
+ parallel_unsequenced_policy(const parallel_unsequenced_policy&) = delete;
+ parallel_unsequenced_policy& operator=(const parallel_unsequenced_policy&) = delete;
+};
+
+inline constexpr parallel_unsequenced_policy par_unseq{__disable_user_instantiations_tag{}};
+
+struct __unsequenced_policy {
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __unsequenced_policy(__disable_user_instantiations_tag) {}
+ __unsequenced_policy(const __unsequenced_policy&) = delete;
+ __unsequenced_policy& operator=(const __unsequenced_policy&) = delete;
+};
+
+constexpr __unsequenced_policy __unseq{__disable_user_instantiations_tag{}};
+
+# if _LIBCPP_STD_VER >= 20
+
+struct unsequenced_policy {
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit unsequenced_policy(__disable_user_instantiations_tag) {}
+ unsequenced_policy(const unsequenced_policy&) = delete;
+ unsequenced_policy& operator=(const unsequenced_policy&) = delete;
+};
+
+inline constexpr unsequenced_policy unseq{__disable_user_instantiations_tag{}};
+
+# endif // _LIBCPP_STD_VER >= 20
+
+} // namespace execution
+
+template <>
+inline constexpr bool is_execution_policy_v<execution::sequenced_policy> = true;
+
+template <>
+inline constexpr bool is_execution_policy_v<execution::parallel_policy> = true;
+
+template <>
+inline constexpr bool is_execution_policy_v<execution::parallel_unsequenced_policy> = true;
+
+template <>
+inline constexpr bool is_execution_policy_v<execution::__unsequenced_policy> = true;
+
+template <>
+inline constexpr bool __is_parallel_execution_policy_impl<execution::parallel_policy> = true;
+
+template <>
+inline constexpr bool __is_parallel_execution_policy_impl<execution::parallel_unsequenced_policy> = true;
+
+template <>
+inline constexpr bool __is_unsequenced_execution_policy_impl<execution::__unsequenced_policy> = true;
+
+template <>
+inline constexpr bool __is_unsequenced_execution_policy_impl<execution::parallel_unsequenced_policy> = true;
+
+# if _LIBCPP_STD_VER >= 20
+template <>
+inline constexpr bool is_execution_policy_v<execution::unsequenced_policy> = true;
+
+template <>
+inline constexpr bool __is_unsequenced_execution_policy_impl<execution::unsequenced_policy> = true;
+
+# endif
+
+template <class _Tp>
+struct is_execution_policy : bool_constant<is_execution_policy_v<_Tp>> {};
+
+template <class _ExecutionPolicy>
+_LIBCPP_HIDE_FROM_ABI auto __remove_parallel_policy(const _ExecutionPolicy&) {
+ if constexpr (is_same_v<_ExecutionPolicy, execution::parallel_policy>) {
+ return execution::sequenced_policy(execution::__disable_user_instantiations_tag{});
+ } else if constexpr (is_same_v<_ExecutionPolicy, execution::parallel_unsequenced_policy>) {
+ return execution::__unsequenced_policy{execution::__disable_user_instantiations_tag{}};
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstddef>
+#endif
+
+#endif // _LIBCPP_EXECUTION
diff --git a/libcxx/include/__cxx03/expected b/libcxx/include/__cxx03/expected
new file mode 100644
index 00000000000000..6a2f12f2bf3b5d
--- /dev/null
+++ b/libcxx/include/__cxx03/expected
@@ -0,0 +1,62 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPECTED
+#define _LIBCPP_EXPECTED
+
+/*
+ Header <expected> synopsis
+
+namespace std {
+ // [expected.unexpected], class template unexpected
+ template<class E> class unexpected;
+
+ // [expected.bad], class template bad_expected_access
+ template<class E> class bad_expected_access;
+
+ // [expected.bad.void], specialization for void
+ template<> class bad_expected_access<void>;
+
+ // in-place construction of unexpected values
+ struct unexpect_t {
+ explicit unexpect_t() = default;
+ };
+ inline constexpr unexpect_t unexpect{};
+
+ // [expected.expected], class template expected
+ template<class T, class E> class expected;
+
+ // [expected.void], partial specialization of expected for void types
+ template<class T, class E> requires is_void_v<T> class expected<T, E>;
+}
+
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 23
+# include <__expected/bad_expected_access.h>
+# include <__expected/expected.h>
+# include <__expected/unexpect.h>
+# include <__expected/unexpected.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstddef>
+# include <initializer_list>
+# include <new>
+#endif
+
+#endif // _LIBCPP_EXPECTED
diff --git a/libcxx/include/__cxx03/experimental/__config b/libcxx/include/__cxx03/experimental/__config
new file mode 100644
index 00000000000000..7b23791511ceff
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__config
@@ -0,0 +1,45 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL_CONFIG
+#define _LIBCPP_EXPERIMENTAL_CONFIG
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#define _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL \
+ namespace std { \
+ namespace experimental {
+#define _LIBCPP_END_NAMESPACE_EXPERIMENTAL \
+ } \
+ }
+
+#define _LIBCPP_BEGIN_NAMESPACE_LFTS _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL inline namespace fundamentals_v1 {
+#define _LIBCPP_END_NAMESPACE_LFTS \
+ } \
+ } \
+ }
+
+#define _LIBCPP_BEGIN_NAMESPACE_LFTS_V2 _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL inline namespace fundamentals_v2 {
+#define _LIBCPP_END_NAMESPACE_LFTS_V2 \
+ } \
+ } \
+ }
+
+// TODO: support more targets
+#if defined(__AVX__)
+# define _LIBCPP_NATIVE_SIMD_WIDTH_IN_BYTES 32
+#else
+# define _LIBCPP_NATIVE_SIMD_WIDTH_IN_BYTES 16
+#endif
+
+#endif
diff --git a/libcxx/include/__cxx03/experimental/__simd/aligned_tag.h b/libcxx/include/__cxx03/experimental/__simd/aligned_tag.h
new file mode 100644
index 00000000000000..31d2b50aa1dd36
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/aligned_tag.h
@@ -0,0 +1,75 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_ALIGNED_TAG_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_ALIGNED_TAG_H
+
+#include <__memory/assume_aligned.h>
+#include <__type_traits/remove_const.h>
+#include <cstddef>
+#include <experimental/__config>
+#include <experimental/__simd/traits.h>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+// memory alignment
+struct element_aligned_tag {
+ template <class _Tp, class _Up = typename _Tp::value_type>
+ static constexpr size_t __alignment = alignof(_Up);
+
+ template <class _Tp, class _Up>
+ static _LIBCPP_HIDE_FROM_ABI constexpr _Up* __apply(_Up* __ptr) {
+ return __ptr;
+ }
+};
+
+template <>
+inline constexpr bool is_simd_flag_type_v<element_aligned_tag> = true;
+
+struct vector_aligned_tag {
+ template <class _Tp, class _Up = typename _Tp::value_type>
+ static constexpr size_t __alignment = memory_alignment_v<_Tp, remove_const_t<_Up>>;
+
+ template <class _Tp, class _Up>
+ static _LIBCPP_HIDE_FROM_ABI constexpr _Up* __apply(_Up* __ptr) {
+ return std::__assume_aligned<__alignment<_Tp, _Up>, _Up>(__ptr);
+ }
+};
+
+template <>
+inline constexpr bool is_simd_flag_type_v<vector_aligned_tag> = true;
+
+template <size_t _Np>
+struct overaligned_tag {
+ template <class _Tp, class _Up = typename _Tp::value_type>
+ static constexpr size_t __alignment = _Np;
+
+ template <class _Tp, class _Up>
+ static _LIBCPP_HIDE_FROM_ABI constexpr _Up* __apply(_Up* __ptr) {
+ return std::__assume_aligned<__alignment<_Tp, _Up>, _Up>(__ptr);
+ }
+};
+
+template <size_t _Np>
+inline constexpr bool is_simd_flag_type_v<overaligned_tag<_Np>> = true;
+
+inline constexpr element_aligned_tag element_aligned{};
+
+inline constexpr vector_aligned_tag vector_aligned{};
+
+template <size_t _Np>
+inline constexpr overaligned_tag<_Np> overaligned{};
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_ALIGNED_TAG_H
diff --git a/libcxx/include/__cxx03/experimental/__simd/declaration.h b/libcxx/include/__cxx03/experimental/__simd/declaration.h
new file mode 100644
index 00000000000000..7b45d035c27121
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/declaration.h
@@ -0,0 +1,81 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_DECLARATION_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_DECLARATION_H
+
+#include <cstddef>
+#include <experimental/__config>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+namespace simd_abi {
+template <int>
+struct __vec_ext;
+struct __scalar;
+
+using scalar = __scalar;
+
+// TODO: make this platform dependent
+template <int _Np>
+using fixed_size = __vec_ext<_Np>;
+
+template <class _Tp>
+inline constexpr int max_fixed_size = 32;
+
+// TODO: make this platform dependent
+template <class _Tp>
+using compatible = __vec_ext<16 / sizeof(_Tp)>;
+
+// TODO: make this platform dependent
+template <class _Tp>
+using native = __vec_ext<_LIBCPP_NATIVE_SIMD_WIDTH_IN_BYTES / sizeof(_Tp)>;
+
+// TODO: make this platform dependent
+template <class _Tp, size_t _Np, class... _Abis>
+struct deduce {
+ using type = fixed_size<_Np>;
+};
+
+// TODO: make this platform dependent
+template <class _Tp, size_t _Np, class... _Abis>
+using deduce_t = typename deduce<_Tp, _Np, _Abis...>::type;
+
+} // namespace simd_abi
+
+template <class _Tp, class _Abi>
+struct __simd_storage;
+
+template <class _Tp, class _Abi>
+struct __mask_storage;
+
+template <class _Tp, class _Abi>
+struct __simd_operations;
+
+template <class _Tp, class _Abi>
+struct __mask_operations;
+
+struct element_aligned_tag;
+struct vector_aligned_tag;
+template <size_t>
+struct overaligned_tag;
+
+template <class _Tp, class _Abi = simd_abi::compatible<_Tp>>
+class simd;
+
+template <class _Tp, class _Abi = simd_abi::compatible<_Tp>>
+class simd_mask;
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_DECLARATION_H
diff --git a/libcxx/include/__cxx03/experimental/__simd/reference.h b/libcxx/include/__cxx03/experimental/__simd/reference.h
new file mode 100644
index 00000000000000..af61dbcc2fe92d
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/reference.h
@@ -0,0 +1,105 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_REFERENCE_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_REFERENCE_H
+
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_same.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <experimental/__config>
+#include <experimental/__simd/utility.h>
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+template <class _Tp, class _Storage, class _Vp>
+class __simd_reference {
+ template <class, class>
+ friend class simd;
+ template <class, class>
+ friend class simd_mask;
+
+ _Storage& __s_;
+ size_t __idx_;
+
+ _LIBCPP_HIDE_FROM_ABI __simd_reference(_Storage& __s, size_t __idx) : __s_(__s), __idx_(__idx) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Vp __get() const noexcept { return __s_.__get(__idx_); }
+
+ _LIBCPP_HIDE_FROM_ABI void __set(_Vp __v) {
+ if constexpr (is_same_v<_Vp, bool>)
+ __s_.__set(__idx_, experimental::__set_all_bits<_Tp>(__v));
+ else
+ __s_.__set(__idx_, __v);
+ }
+
+public:
+ using value_type = _Vp;
+
+ __simd_reference() = delete;
+ __simd_reference(const __simd_reference&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI operator value_type() const noexcept { return __get(); }
+
+ template <class _Up, enable_if_t<is_assignable_v<value_type&, _Up&&>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI __simd_reference operator=(_Up&& __v) && noexcept {
+ __set(static_cast<value_type>(std::forward<_Up>(__v)));
+ return {__s_, __idx_};
+ }
+
+ // Note: This approach might not fully align with the specification,
+ // which might be a wording defect. (https://wg21.link/N4808 section 9.6.3)
+ template <class _Tp1, class _Storage1, class _Vp1>
+ friend void
+ swap(__simd_reference<_Tp1, _Storage1, _Vp1>&& __a, __simd_reference<_Tp1, _Storage1, _Vp1>&& __b) noexcept;
+
+ template <class _Tp1, class _Storage1, class _Vp1>
+ friend void swap(_Vp1& __a, __simd_reference<_Tp1, _Storage1, _Vp1>&& __b) noexcept;
+
+ template <class _Tp1, class _Storage1, class _Vp1>
+ friend void swap(__simd_reference<_Tp1, _Storage1, _Vp1>&& __a, _Vp1& __b) noexcept;
+};
+
+template <class _Tp, class _Storage, class _Vp>
+_LIBCPP_HIDE_FROM_ABI void
+swap(__simd_reference<_Tp, _Storage, _Vp>&& __a, __simd_reference<_Tp, _Storage, _Vp>&& __b) noexcept {
+ _Vp __tmp(std::move(__a));
+ std::move(__a) = std::move(__b);
+ std::move(__b) = std::move(__tmp);
+}
+
+template <class _Tp, class _Storage, class _Vp>
+_LIBCPP_HIDE_FROM_ABI void swap(_Vp& __a, __simd_reference<_Tp, _Storage, _Vp>&& __b) noexcept {
+ _Vp __tmp(std::move(__a));
+ __a = std::move(__b);
+ std::move(__b) = std::move(__tmp);
+}
+
+template <class _Tp, class _Storage, class _Vp>
+_LIBCPP_HIDE_FROM_ABI void swap(__simd_reference<_Tp, _Storage, _Vp>&& __a, _Vp& __b) noexcept {
+ _Vp __tmp(std::move(__a));
+ std::move(__a) = std::move(__b);
+ __b = std::move(__tmp);
+}
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_REFERENCE_H
diff --git a/libcxx/include/__cxx03/experimental/__simd/scalar.h b/libcxx/include/__cxx03/experimental/__simd/scalar.h
new file mode 100644
index 00000000000000..1add4653209ace
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/scalar.h
@@ -0,0 +1,87 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_SCALAR_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_SCALAR_H
+
+#include <__assert>
+#include <cstddef>
+#include <experimental/__config>
+#include <experimental/__simd/declaration.h>
+#include <experimental/__simd/traits.h>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+namespace simd_abi {
+struct __scalar {
+ static constexpr size_t __simd_size = 1;
+};
+} // namespace simd_abi
+
+template <>
+inline constexpr bool is_abi_tag_v<simd_abi::__scalar> = true;
+
+template <class _Tp>
+struct __simd_storage<_Tp, simd_abi::__scalar> {
+ _Tp __data;
+
+ _LIBCPP_HIDE_FROM_ABI _Tp __get([[maybe_unused]] size_t __idx) const noexcept {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__idx == 0, "Index is out of bounds");
+ return __data;
+ }
+ _LIBCPP_HIDE_FROM_ABI void __set([[maybe_unused]] size_t __idx, _Tp __v) noexcept {
+ _LIBCPP_ASSERT_UNCATEGORIZED(__idx == 0, "Index is out of bounds");
+ __data = __v;
+ }
+};
+
+template <class _Tp>
+struct __mask_storage<_Tp, simd_abi::__scalar> : __simd_storage<bool, simd_abi::__scalar> {};
+
+template <class _Tp>
+struct __simd_operations<_Tp, simd_abi::__scalar> {
+ using _SimdStorage = __simd_storage<_Tp, simd_abi::__scalar>;
+ using _MaskStorage = __mask_storage<_Tp, simd_abi::__scalar>;
+
+ static _LIBCPP_HIDE_FROM_ABI _SimdStorage __broadcast(_Tp __v) noexcept { return {__v}; }
+
+ template <class _Generator>
+ static _LIBCPP_HIDE_FROM_ABI _SimdStorage __generate(_Generator&& __g) noexcept {
+ return {__g(std::integral_constant<size_t, 0>())};
+ }
+
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI void __load(_SimdStorage& __s, const _Up* __mem) noexcept {
+ __s.__data = static_cast<_Tp>(__mem[0]);
+ }
+
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI void __store(_SimdStorage __s, _Up* __mem) noexcept {
+ *__mem = static_cast<_Up>(__s.__data);
+ }
+};
+
+template <class _Tp>
+struct __mask_operations<_Tp, simd_abi::__scalar> {
+ using _MaskStorage = __mask_storage<_Tp, simd_abi::__scalar>;
+
+ static _LIBCPP_HIDE_FROM_ABI _MaskStorage __broadcast(bool __v) noexcept { return {__v}; }
+
+ static _LIBCPP_HIDE_FROM_ABI void __load(_MaskStorage& __s, const bool* __mem) noexcept { __s.__data = __mem[0]; }
+
+ static _LIBCPP_HIDE_FROM_ABI void __store(_MaskStorage __s, bool* __mem) noexcept { __mem[0] = __s.__data; }
+};
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_SCALAR_H
diff --git a/libcxx/include/__cxx03/experimental/__simd/simd.h b/libcxx/include/__cxx03/experimental/__simd/simd.h
new file mode 100644
index 00000000000000..37e334aad6da07
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/simd.h
@@ -0,0 +1,102 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_SIMD_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_SIMD_H
+
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/forward.h>
+#include <cstddef>
+#include <experimental/__config>
+#include <experimental/__simd/declaration.h>
+#include <experimental/__simd/reference.h>
+#include <experimental/__simd/traits.h>
+#include <experimental/__simd/utility.h>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+
+// class template simd [simd.class]
+// TODO: implement simd class
+template <class _Tp, class _Abi>
+class simd {
+ using _Impl = __simd_operations<_Tp, _Abi>;
+ using _Storage = typename _Impl::_SimdStorage;
+
+ _Storage __s_;
+
+public:
+ using value_type = _Tp;
+ using reference = __simd_reference<_Tp, _Storage, value_type>;
+ using mask_type = simd_mask<_Tp, _Abi>;
+ using abi_type = _Abi;
+
+ static _LIBCPP_HIDE_FROM_ABI constexpr size_t size() noexcept { return simd_size_v<value_type, abi_type>; }
+
+ _LIBCPP_HIDE_FROM_ABI simd() noexcept = default;
+
+ // broadcast constructor
+ template <class _Up, enable_if_t<__can_broadcast_v<value_type, __remove_cvref_t<_Up>>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI simd(_Up&& __v) noexcept : __s_(_Impl::__broadcast(static_cast<value_type>(__v))) {}
+
+ // implicit type conversion constructor
+ template <class _Up,
+ enable_if_t<!is_same_v<_Up, _Tp> && is_same_v<abi_type, simd_abi::fixed_size<size()>> &&
+ __is_non_narrowing_convertible_v<_Up, value_type>,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI simd(const simd<_Up, simd_abi::fixed_size<size()>>& __v) noexcept {
+ for (size_t __i = 0; __i < size(); __i++) {
+ (*this)[__i] = static_cast<value_type>(__v[__i]);
+ }
+ }
+
+ // generator constructor
+ template <class _Generator, enable_if_t<__can_generate_v<value_type, _Generator, size()>, int> = 0>
+ explicit _LIBCPP_HIDE_FROM_ABI simd(_Generator&& __g) noexcept
+ : __s_(_Impl::__generate(std::forward<_Generator>(__g))) {}
+
+ // load constructor
+ template <class _Up, class _Flags, enable_if_t<__is_vectorizable_v<_Up> && is_simd_flag_type_v<_Flags>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI simd(const _Up* __mem, _Flags) {
+ _Impl::__load(__s_, _Flags::template __apply<simd>(__mem));
+ }
+
+ // copy functions
+ template <class _Up, class _Flags, enable_if_t<__is_vectorizable_v<_Up> && is_simd_flag_type_v<_Flags>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void copy_from(const _Up* __mem, _Flags) {
+ _Impl::__load(__s_, _Flags::template __apply<simd>(__mem));
+ }
+
+ template <class _Up, class _Flags, enable_if_t<__is_vectorizable_v<_Up> && is_simd_flag_type_v<_Flags>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void copy_to(_Up* __mem, _Flags) const {
+ _Impl::__store(__s_, _Flags::template __apply<simd>(__mem));
+ }
+
+ // scalar access [simd.subscr]
+ _LIBCPP_HIDE_FROM_ABI reference operator[](size_t __i) noexcept { return reference(__s_, __i); }
+ _LIBCPP_HIDE_FROM_ABI value_type operator[](size_t __i) const noexcept { return __s_.__get(__i); }
+};
+
+template <class _Tp, class _Abi>
+inline constexpr bool is_simd_v<simd<_Tp, _Abi>> = true;
+
+template <class _Tp>
+using native_simd = simd<_Tp, simd_abi::native<_Tp>>;
+
+template <class _Tp, int _Np>
+using fixed_size_simd = simd<_Tp, simd_abi::fixed_size<_Np>>;
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_SIMD_H
diff --git a/libcxx/include/__cxx03/experimental/__simd/simd_mask.h b/libcxx/include/__cxx03/experimental/__simd/simd_mask.h
new file mode 100644
index 00000000000000..fd6dee2e28ee91
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/simd_mask.h
@@ -0,0 +1,90 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_SIMD_MASK_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_SIMD_MASK_H
+
+#include <__type_traits/is_same.h>
+#include <cstddef>
+#include <experimental/__config>
+#include <experimental/__simd/declaration.h>
+#include <experimental/__simd/reference.h>
+#include <experimental/__simd/traits.h>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+
+// class template simd_mask [simd.mask.class]
+// TODO: implement simd_mask class
+template <class _Tp, class _Abi>
+class simd_mask {
+ using _Impl = __mask_operations<_Tp, _Abi>;
+ using _Storage = typename _Impl::_MaskStorage;
+
+ _Storage __s_;
+
+public:
+ using value_type = bool;
+ using reference = __simd_reference<_Tp, _Storage, value_type>;
+ using simd_type = simd<_Tp, _Abi>;
+ using abi_type = _Abi;
+
+ static _LIBCPP_HIDE_FROM_ABI constexpr size_t size() noexcept { return simd_type::size(); }
+
+ _LIBCPP_HIDE_FROM_ABI simd_mask() noexcept = default;
+
+ // broadcast constructor
+ _LIBCPP_HIDE_FROM_ABI explicit simd_mask(value_type __v) noexcept : __s_(_Impl::__broadcast(__v)) {}
+
+ // implicit type conversion constructor
+ template <class _Up, enable_if_t<!is_same_v<_Up, _Tp> && is_same_v<abi_type, simd_abi::fixed_size<size()>>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI simd_mask(const simd_mask<_Up, simd_abi::fixed_size<size()>>& __v) noexcept {
+ for (size_t __i = 0; __i < size(); __i++) {
+ (*this)[__i] = __v[__i];
+ }
+ }
+
+ // load constructor
+ template <class _Flags, enable_if_t<is_simd_flag_type_v<_Flags>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI simd_mask(const value_type* __mem, _Flags) {
+ _Impl::__load(__s_, _Flags::template __apply<simd_mask>(__mem));
+ }
+
+ // copy functions
+ template <class _Flags, enable_if_t<is_simd_flag_type_v<_Flags>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void copy_from(const value_type* __mem, _Flags) {
+ _Impl::__load(__s_, _Flags::template __apply<simd_mask>(__mem));
+ }
+
+ template <class _Flags, enable_if_t<is_simd_flag_type_v<_Flags>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void copy_to(value_type* __mem, _Flags) const {
+ _Impl::__store(__s_, _Flags::template __apply<simd_mask>(__mem));
+ }
+
+ // scalar access [simd.mask.subscr]
+ _LIBCPP_HIDE_FROM_ABI reference operator[](size_t __i) noexcept { return reference(__s_, __i); }
+ _LIBCPP_HIDE_FROM_ABI value_type operator[](size_t __i) const noexcept { return __s_.__get(__i); }
+};
+
+template <class _Tp, class _Abi>
+inline constexpr bool is_simd_mask_v<simd_mask<_Tp, _Abi>> = true;
+
+template <class _Tp>
+using native_simd_mask = simd_mask<_Tp, simd_abi::native<_Tp>>;
+
+template <class _Tp, int _Np>
+using fixed_size_simd_mask = simd_mask<_Tp, simd_abi::fixed_size<_Np>>;
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_SIMD_MASK_H
diff --git a/libcxx/include/__cxx03/experimental/__simd/traits.h b/libcxx/include/__cxx03/experimental/__simd/traits.h
new file mode 100644
index 00000000000000..ec25b4bfa7f95e
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/traits.h
@@ -0,0 +1,75 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_TRAITS_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_TRAITS_H
+
+#include <__bit/bit_ceil.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+#include <cstddef>
+#include <experimental/__config>
+#include <experimental/__simd/declaration.h>
+#include <experimental/__simd/utility.h>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+
+// traits [simd.traits]
+template <class _Tp>
+inline constexpr bool is_abi_tag_v = false;
+
+template <class _Tp>
+struct is_abi_tag : bool_constant<is_abi_tag_v<_Tp>> {};
+
+template <class _Tp>
+inline constexpr bool is_simd_v = false;
+
+template <class _Tp>
+struct is_simd : bool_constant<is_simd_v<_Tp>> {};
+
+template <class _Tp>
+inline constexpr bool is_simd_mask_v = false;
+
+template <class _Tp>
+struct is_simd_mask : bool_constant<is_simd_mask_v<_Tp>> {};
+
+template <class _Tp>
+inline constexpr bool is_simd_flag_type_v = false;
+
+template <class _Tp>
+struct is_simd_flag_type : bool_constant<is_simd_flag_type_v<_Tp>> {};
+
+template <class _Tp, class _Abi = simd_abi::compatible<_Tp>, bool = (__is_vectorizable_v<_Tp> && is_abi_tag_v<_Abi>)>
+struct simd_size : integral_constant<size_t, _Abi::__simd_size> {};
+
+template <class _Tp, class _Abi>
+struct simd_size<_Tp, _Abi, false> {};
+
+template <class _Tp, class _Abi = simd_abi::compatible<_Tp>>
+inline constexpr size_t simd_size_v = simd_size<_Tp, _Abi>::value;
+
+template <class _Tp,
+ class _Up = typename _Tp::value_type,
+ bool = (is_simd_v<_Tp> && __is_vectorizable_v<_Up>) || (is_simd_mask_v<_Tp> && is_same_v<_Up, bool>)>
+struct memory_alignment : integral_constant<size_t, std::__bit_ceil(sizeof(_Up) * _Tp::size())> {};
+
+template <class _Tp, class _Up>
+struct memory_alignment<_Tp, _Up, false> {};
+
+template <class _Tp, class _Up = typename _Tp::value_type>
+inline constexpr size_t memory_alignment_v = memory_alignment<_Tp, _Up>::value;
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_TRAITS_H
diff --git a/libcxx/include/__cxx03/experimental/__simd/utility.h b/libcxx/include/__cxx03/experimental/__simd/utility.h
new file mode 100644
index 00000000000000..708fa3d8f72cef
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/utility.h
@@ -0,0 +1,103 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_UTILITY_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_UTILITY_H
+
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_unsigned.h>
+#include <__type_traits/is_volatile.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <__utility/integer_sequence.h>
+#include <cstddef>
+#include <cstdint>
+#include <experimental/__config>
+#include <limits>
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+template <class _Tp>
+inline constexpr bool __is_vectorizable_v =
+ is_arithmetic_v<_Tp> && !is_const_v<_Tp> && !is_volatile_v<_Tp> && !is_same_v<_Tp, bool>;
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI auto __choose_mask_type() {
+ if constexpr (sizeof(_Tp) == 1) {
+ return uint8_t{};
+ } else if constexpr (sizeof(_Tp) == 2) {
+ return uint16_t{};
+ } else if constexpr (sizeof(_Tp) == 4) {
+ return uint32_t{};
+ } else if constexpr (sizeof(_Tp) == 8) {
+ return uint64_t{};
+ }
+# ifndef _LIBCPP_HAS_NO_INT128
+ else if constexpr (sizeof(_Tp) == 16) {
+ return __uint128_t{};
+ }
+# endif
+ else
+ static_assert(sizeof(_Tp) == 0, "Unexpected size");
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI auto constexpr __set_all_bits(bool __v) {
+ return __v ? (numeric_limits<decltype(__choose_mask_type<_Tp>())>::max()) : 0;
+}
+
+template <class _From, class _To, class = void>
+inline constexpr bool __is_non_narrowing_convertible_v = false;
+
+template <class _From, class _To>
+inline constexpr bool __is_non_narrowing_convertible_v<_From, _To, std::void_t<decltype(_To{std::declval<_From>()})>> =
+ true;
+
+template <class _Tp, class _Up>
+inline constexpr bool __can_broadcast_v =
+ (__is_vectorizable_v<_Up> && __is_non_narrowing_convertible_v<_Up, _Tp>) ||
+ (!__is_vectorizable_v<_Up> && is_convertible_v<_Up, _Tp>) || is_same_v<_Up, int> ||
+ (is_same_v<_Up, unsigned int> && is_unsigned_v<_Tp>);
+
+template <class _Tp, class _Generator, std::size_t _Idx, class = void>
+inline constexpr bool __is_well_formed = false;
+
+template <class _Tp, class _Generator, std::size_t _Idx>
+inline constexpr bool
+ __is_well_formed<_Tp,
+ _Generator,
+ _Idx,
+ std::void_t<decltype(std::declval<_Generator>()(integral_constant<size_t, _Idx>()))>> =
+ __can_broadcast_v<_Tp, decltype(std::declval<_Generator>()(integral_constant<size_t, _Idx>()))>;
+
+template <class _Tp, class _Generator, std::size_t... _Idxes>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __can_generate(index_sequence<_Idxes...>) {
+ return (true && ... && __is_well_formed<_Tp, _Generator, _Idxes>);
+}
+
+template <class _Tp, class _Generator, std::size_t _Size>
+inline constexpr bool __can_generate_v = experimental::__can_generate<_Tp, _Generator>(make_index_sequence<_Size>());
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_UTILITY_H
diff --git a/libcxx/include/__cxx03/experimental/__simd/vec_ext.h b/libcxx/include/__cxx03/experimental/__simd/vec_ext.h
new file mode 100644
index 00000000000000..316866b84873dd
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/__simd/vec_ext.h
@@ -0,0 +1,119 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL___SIMD_VEC_EXT_H
+#define _LIBCPP_EXPERIMENTAL___SIMD_VEC_EXT_H
+
+#include <__assert>
+#include <__bit/bit_ceil.h>
+#include <__utility/forward.h>
+#include <__utility/integer_sequence.h>
+#include <cstddef>
+#include <experimental/__config>
+#include <experimental/__simd/declaration.h>
+#include <experimental/__simd/traits.h>
+#include <experimental/__simd/utility.h>
+
+#if _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+inline namespace parallelism_v2 {
+namespace simd_abi {
+template <int _Np>
+struct __vec_ext {
+ static constexpr size_t __simd_size = _Np;
+};
+} // namespace simd_abi
+
+template <int _Np>
+inline constexpr bool is_abi_tag_v<simd_abi::__vec_ext<_Np>> = _Np > 0 && _Np <= 32;
+
+template <class _Tp, int _Np>
+struct __simd_storage<_Tp, simd_abi::__vec_ext<_Np>> {
+ _Tp __data __attribute__((__vector_size__(std::__bit_ceil((sizeof(_Tp) * _Np)))));
+
+ _LIBCPP_HIDE_FROM_ABI _Tp __get(size_t __idx) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx >= 0 && __idx < _Np, "Index is out of bounds");
+ return __data[__idx];
+ }
+ _LIBCPP_HIDE_FROM_ABI void __set(size_t __idx, _Tp __v) noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx >= 0 && __idx < _Np, "Index is out of bounds");
+ __data[__idx] = __v;
+ }
+};
+
+template <class _Tp, int _Np>
+struct __mask_storage<_Tp, simd_abi::__vec_ext<_Np>>
+ : __simd_storage<decltype(experimental::__choose_mask_type<_Tp>()), simd_abi::__vec_ext<_Np>> {};
+
+template <class _Tp, int _Np>
+struct __simd_operations<_Tp, simd_abi::__vec_ext<_Np>> {
+ using _SimdStorage = __simd_storage<_Tp, simd_abi::__vec_ext<_Np>>;
+ using _MaskStorage = __mask_storage<_Tp, simd_abi::__vec_ext<_Np>>;
+
+ static _LIBCPP_HIDE_FROM_ABI _SimdStorage __broadcast(_Tp __v) noexcept {
+ _SimdStorage __result;
+ for (int __i = 0; __i < _Np; ++__i) {
+ __result.__set(__i, __v);
+ }
+ return __result;
+ }
+
+ template <class _Generator, size_t... _Is>
+ static _LIBCPP_HIDE_FROM_ABI _SimdStorage __generate_init(_Generator&& __g, std::index_sequence<_Is...>) {
+ return _SimdStorage{{__g(std::integral_constant<size_t, _Is>())...}};
+ }
+
+ template <class _Generator>
+ static _LIBCPP_HIDE_FROM_ABI _SimdStorage __generate(_Generator&& __g) noexcept {
+ return __generate_init(std::forward<_Generator>(__g), std::make_index_sequence<_Np>());
+ }
+
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI void __load(_SimdStorage& __s, const _Up* __mem) noexcept {
+ for (size_t __i = 0; __i < _Np; __i++)
+ __s.__data[__i] = static_cast<_Tp>(__mem[__i]);
+ }
+
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI void __store(_SimdStorage __s, _Up* __mem) noexcept {
+ for (size_t __i = 0; __i < _Np; __i++)
+ __mem[__i] = static_cast<_Up>(__s.__data[__i]);
+ }
+};
+
+template <class _Tp, int _Np>
+struct __mask_operations<_Tp, simd_abi::__vec_ext<_Np>> {
+ using _MaskStorage = __mask_storage<_Tp, simd_abi::__vec_ext<_Np>>;
+
+ static _LIBCPP_HIDE_FROM_ABI _MaskStorage __broadcast(bool __v) noexcept {
+ _MaskStorage __result;
+ auto __all_bits_v = experimental::__set_all_bits<_Tp>(__v);
+ for (int __i = 0; __i < _Np; ++__i) {
+ __result.__set(__i, __all_bits_v);
+ }
+ return __result;
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI void __load(_MaskStorage& __s, const bool* __mem) noexcept {
+ for (size_t __i = 0; __i < _Np; __i++)
+ __s.__data[__i] = experimental::__set_all_bits<_Tp>(__mem[__i]);
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI void __store(_MaskStorage __s, bool* __mem) noexcept {
+ for (size_t __i = 0; __i < _Np; __i++)
+ __mem[__i] = static_cast<bool>(__s.__data[__i]);
+ }
+};
+
+} // namespace parallelism_v2
+_LIBCPP_END_NAMESPACE_EXPERIMENTAL
+
+#endif // _LIBCPP_STD_VER >= 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
+#endif // _LIBCPP_EXPERIMENTAL___SIMD_VEC_EXT_H
diff --git a/libcxx/include/__cxx03/experimental/iterator b/libcxx/include/__cxx03/experimental/iterator
new file mode 100644
index 00000000000000..de82da2d3d72bd
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/iterator
@@ -0,0 +1,127 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL_ITERATOR
+#define _LIBCPP_EXPERIMENTAL_ITERATOR
+
+/*
+namespace std {
+ namespace experimental {
+ inline namespace fundamentals_v2 {
+
+ template <class DelimT, class charT = char, class traits = char_traits<charT>>
+ class ostream_joiner {
+ public:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef basic_ostream<charT, traits> ostream_type;
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+ typedef void difference_type;
+ typedef void pointer;
+ typedef void reference;
+
+ ostream_joiner(ostream_type& s, const DelimT& delimiter);
+ ostream_joiner(ostream_type& s, DelimT&& delimiter);
+
+ template<typename T>
+ ostream_joiner& operator=(const T& value);
+
+ ostream_joiner& operator*() noexcept;
+ ostream_joiner& operator++() noexcept;
+ ostream_joiner& operator++(int) noexcept;
+ private:
+ ostream_type* out_stream; // exposition only
+ DelimT delim; // exposition only
+ bool first_element; // exposition only
+ };
+
+ template <class charT, class traits, class DelimT>
+ ostream_joiner<decay_t<DelimT>, charT, traits>
+ make_ostream_joiner(basic_ostream<charT, traits>& os, DelimT&& delimiter);
+
+ } // inline namespace fundamentals_v2
+ } // namespace experimental
+} // namespace std
+
+*/
+
+#include <__memory/addressof.h>
+#include <__type_traits/decay.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <experimental/__config>
+#include <iterator>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 14
+
+_LIBCPP_BEGIN_NAMESPACE_LFTS
+
+template <class _Delim, class _CharT = char, class _Traits = char_traits<_CharT>>
+class ostream_joiner {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef basic_ostream<char_type, traits_type> ostream_type;
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+ typedef void difference_type;
+ typedef void pointer;
+ typedef void reference;
+
+ _LIBCPP_HIDE_FROM_ABI ostream_joiner(ostream_type& __os, _Delim&& __d)
+ : __output_iter_(std::addressof(__os)), __delim_(std::move(__d)), __first_(true) {}
+
+ _LIBCPP_HIDE_FROM_ABI ostream_joiner(ostream_type& __os, const _Delim& __d)
+ : __output_iter_(std::addressof(__os)), __delim_(__d), __first_(true) {}
+
+ template <typename _Tp>
+ _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator=(const _Tp& __v) {
+ if (!__first_)
+ *__output_iter_ << __delim_;
+ __first_ = false;
+ *__output_iter_ << __v;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator*() _NOEXCEPT { return *this; }
+ _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator++() _NOEXCEPT { return *this; }
+ _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator++(int) _NOEXCEPT { return *this; }
+
+private:
+ ostream_type* __output_iter_;
+ _Delim __delim_;
+ bool __first_;
+};
+
+template <class _CharT, class _Traits, class _Delim>
+_LIBCPP_HIDE_FROM_ABI ostream_joiner<__decay_t<_Delim>, _CharT, _Traits>
+make_ostream_joiner(basic_ostream<_CharT, _Traits>& __os, _Delim&& __d) {
+ return ostream_joiner<__decay_t<_Delim>, _CharT, _Traits>(__os, std::forward<_Delim>(__d));
+}
+
+_LIBCPP_END_NAMESPACE_LFTS
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <iosfwd>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_EXPERIMENTAL_ITERATOR
diff --git a/libcxx/include/__cxx03/experimental/memory b/libcxx/include/__cxx03/experimental/memory
new file mode 100644
index 00000000000000..e9663d43a8ab73
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/memory
@@ -0,0 +1,198 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL_MEMORY
+#define _LIBCPP_EXPERIMENTAL_MEMORY
+
+/*
+ experimental/memory synopsis
+
+namespace std::experimental::inline fundamentals_v2 {
+
+template <class W> class observer_ptr {
+public:
+ using element_type = W;
+ using pointer = add_pointer_t<W>; // exposition-only
+ using reference = add_lvalue_reference_t<W>; // exposition-only
+
+ // default ctor
+ constexpr observer_ptr() noexcept;
+
+ // pointer-accepting ctors
+ constexpr observer_ptr(nullptr_t) noexcept;
+ constexpr explicit observer_ptr(pointer) noexcept;
+
+ // copying ctors (in addition to compiler-generated copy ctor)
+ template <class W2> constexpr observer_ptr(observer_ptr<W2>) noexcept;
+
+ // observers
+ constexpr pointer get() const noexcept;
+ constexpr reference operator*() const;
+ constexpr pointer operator->() const noexcept;
+ constexpr explicit operator bool() const noexcept;
+
+ // conversions
+ constexpr explicit operator pointer() const noexcept;
+
+ // modifiers
+ constexpr pointer release() noexcept;
+ constexpr void reset(pointer = nullptr) noexcept;
+ constexpr void swap(observer_ptr&) noexcept;
+};
+
+}
+*/
+
+#include <__functional/hash.h>
+#include <__functional/operations.h>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_convertible.h>
+#include <cstddef>
+#include <experimental/__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifdef _LIBCPP_ENABLE_EXPERIMENTAL
+
+_LIBCPP_BEGIN_NAMESPACE_LFTS_V2
+
+# if _LIBCPP_STD_VER >= 17
+
+template <class _Wp>
+class observer_ptr {
+public:
+ using element_type = _Wp;
+
+ // constructors
+ _LIBCPP_HIDE_FROM_ABI constexpr observer_ptr() noexcept : __ptr_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI constexpr observer_ptr(nullptr_t) noexcept : __ptr_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit observer_ptr(element_type* __p) noexcept : __ptr_(__p) {}
+
+ template <class _W2, __enable_if_t<is_convertible<_W2*, _Wp*>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr observer_ptr(observer_ptr<_W2> __other) noexcept : __ptr_(__other.get()) {}
+
+ // observers
+ _LIBCPP_HIDE_FROM_ABI constexpr element_type* get() const noexcept { return __ptr_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr add_lvalue_reference_t<_Wp> operator*() const { return *__ptr_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr element_type* operator->() const noexcept { return __ptr_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return __ptr_ != nullptr; }
+
+ // conversions
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator element_type*() const noexcept { return __ptr_; }
+
+ // modifiers
+ _LIBCPP_HIDE_FROM_ABI constexpr void reset(element_type* __p = nullptr) noexcept { __ptr_ = __p; }
+ _LIBCPP_HIDE_FROM_ABI constexpr void swap(observer_ptr& __other) noexcept {
+ observer_ptr __tmp = __other;
+ __other = *this;
+ *this = __tmp;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr element_type* release() noexcept {
+ observer_ptr __p;
+ __p.swap(*this);
+ return __p.get();
+ }
+
+private:
+ element_type* __ptr_;
+};
+
+// specializations
+
+template <class _Wp>
+_LIBCPP_HIDE_FROM_ABI constexpr void swap(observer_ptr<_Wp>& __a, observer_ptr<_Wp>& __b) noexcept {
+ __a.swap(__b);
+}
+
+template <class _Wp>
+_LIBCPP_HIDE_FROM_ABI observer_ptr<_Wp> make_observer(_Wp* __ptr) noexcept {
+ return observer_ptr<_Wp>{__ptr};
+}
+
+template <class _W1, class _W2>
+_LIBCPP_HIDE_FROM_ABI bool operator==(observer_ptr<_W1> __a, observer_ptr<_W2> __b) {
+ return __a.get() == __b.get();
+}
+
+template <class _W1, class _W2>
+_LIBCPP_HIDE_FROM_ABI bool operator!=(observer_ptr<_W1> __a, observer_ptr<_W2> __b) {
+ return !(__a == __b);
+}
+
+template <class _Wp>
+_LIBCPP_HIDE_FROM_ABI bool operator==(observer_ptr<_Wp> __p, nullptr_t) {
+ return !__p;
+}
+
+template <class _Wp>
+_LIBCPP_HIDE_FROM_ABI bool operator==(nullptr_t, observer_ptr<_Wp> __p) {
+ return !__p;
+}
+
+template <class _Wp>
+_LIBCPP_HIDE_FROM_ABI bool operator!=(observer_ptr<_Wp> __p, nullptr_t) {
+ return (bool)__p;
+}
+
+template <class _Wp>
+_LIBCPP_HIDE_FROM_ABI bool operator!=(nullptr_t, observer_ptr<_Wp> __p) {
+ return (bool)__p;
+}
+
+template <class _W1, class _W2>
+_LIBCPP_HIDE_FROM_ABI bool operator<(observer_ptr<_W1> __a, observer_ptr<_W2> __b) {
+ return std::less<typename std::common_type<_W1*, _W2*>::type>()(__a.get(), __b.get());
+}
+
+template <class _W1, class _W2>
+_LIBCPP_HIDE_FROM_ABI bool operator>(observer_ptr<_W1> __a, observer_ptr<_W2> __b) {
+ return __b < __a;
+}
+
+template <class _W1, class _W2>
+_LIBCPP_HIDE_FROM_ABI bool operator<=(observer_ptr<_W1> __a, observer_ptr<_W2> __b) {
+ return !(__a > __b);
+}
+
+template <class _W1, class _W2>
+_LIBCPP_HIDE_FROM_ABI bool operator>=(observer_ptr<_W1> __a, observer_ptr<_W2> __b) {
+ return !(__a < __b);
+}
+
+# endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_LFTS_V2
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// hash
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+struct hash<experimental::observer_ptr<_Tp>> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const experimental::observer_ptr<_Tp>& __ptr) const noexcept {
+ return hash<_Tp*>()(__ptr.get());
+ }
+};
+# endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_ENABLE_EXPERIMENTAL
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <limits>
+#endif
+
+#endif /* _LIBCPP_EXPERIMENTAL_MEMORY */
diff --git a/libcxx/include/__cxx03/experimental/propagate_const b/libcxx/include/__cxx03/experimental/propagate_const
new file mode 100644
index 00000000000000..d7a695d8388923
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/propagate_const
@@ -0,0 +1,490 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL_PROPAGATE_CONST
+#define _LIBCPP_EXPERIMENTAL_PROPAGATE_CONST
+
+/*
+ propagate_const synopsis
+
+ namespace std { namespace experimental { inline namespace fundamentals_v2 {
+
+ // [propagate_const]
+ template <class T> class propagate_const;
+
+ // [propagate_const.underlying], underlying pointer access
+ constexpr const _Tp& get_underlying(const propagate_const<T>& pt) noexcept;
+ constexpr T& get_underlying(propagate_const<T>& pt) noexcept;
+
+ // [propagate_const.relational], relational operators
+ template <class T> constexpr bool operator==(const propagate_const<T>& pt, nullptr_t);
+ template <class T> constexpr bool operator==(nullptr_t, const propagate_const<T>& pu);
+ template <class T> constexpr bool operator!=(const propagate_const<T>& pt, nullptr_t);
+ template <class T> constexpr bool operator!=(nullptr_t, const propagate_const<T>& pu);
+ template <class T, class U> constexpr bool operator==(const propagate_const<T>& pt, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator!=(const propagate_const<T>& pt, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator<(const propagate_const<T>& pt, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator>(const propagate_const<T>& pt, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator<=(const propagate_const<T>& pt, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator>=(const propagate_const<T>& pt, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator==(const propagate_const<T>& pt, const _Up& u);
+ template <class T, class U> constexpr bool operator!=(const propagate_const<T>& pt, const _Up& u);
+ template <class T, class U> constexpr bool operator<(const propagate_const<T>& pt, const _Up& u);
+ template <class T, class U> constexpr bool operator>(const propagate_const<T>& pt, const _Up& u);
+ template <class T, class U> constexpr bool operator<=(const propagate_const<T>& pt, const _Up& u);
+ template <class T, class U> constexpr bool operator>=(const propagate_const<T>& pt, const _Up& u);
+ template <class T, class U> constexpr bool operator==(const _Tp& t, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator!=(const _Tp& t, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator<(const _Tp& t, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator>(const _Tp& t, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator<=(const _Tp& t, const propagate_const<_Up>& pu);
+ template <class T, class U> constexpr bool operator>=(const _Tp& t, const propagate_const<_Up>& pu);
+
+ // [propagate_const.algorithms], specialized algorithms
+ template <class T> constexpr void swap(propagate_const<T>& pt, propagate_const<T>& pu) noexcept(see below);
+
+ template <class T>
+ class propagate_const
+ {
+
+ public:
+ typedef remove_reference_t<decltype(*declval<T&>())> element_type;
+
+ // [propagate_const.ctor], constructors
+ constexpr propagate_const() = default;
+ propagate_const(const propagate_const& p) = delete;
+ constexpr propagate_const(propagate_const&& p) = default;
+ template <class U> EXPLICIT constexpr propagate_const(propagate_const<_Up>&& pu); // see below
+ template <class U> EXPLICIT constexpr propagate_const(U&& u); // see below
+
+ // [propagate_const.assignment], assignment
+ propagate_const& operator=(const propagate_const& p) = delete;
+ constexpr propagate_const& operator=(propagate_const&& p) = default;
+ template <class U> constexpr propagate_const& operator=(propagate_const<_Up>&& pu);
+ template <class U> constexpr propagate_const& operator=(U&& u); // see below
+
+ // [propagate_const.const_observers], const observers
+ explicit constexpr operator bool() const;
+ constexpr const element_type* operator->() const;
+ constexpr operator const element_type*() const; // Not always defined
+ constexpr const element_type& operator*() const;
+ constexpr const element_type* get() const;
+
+ // [propagate_const.non_const_observers], non-const observers
+ constexpr element_type* operator->();
+ constexpr operator element_type*(); // Not always defined
+ constexpr element_type& operator*();
+ constexpr element_type* get();
+
+ // [propagate_const.modifiers], modifiers
+ constexpr void swap(propagate_const& pt) noexcept(see below)
+
+ private:
+ T t_; // exposition only
+ };
+
+ } // namespace fundamentals_v2
+ } // namespace experimental
+
+ // [propagate_const.hash], hash support
+ template <class T> struct hash<experimental::propagate_const<T>>;
+
+ // [propagate_const.comparison_function_objects], comparison function objects
+ template <class T> struct equal_to<experimental::propagate_const<T>>;
+ template <class T> struct not_equal_to<experimental::propagate_const<T>>;
+ template <class T> struct less<experimental::propagate_const<T>>;
+ template <class T> struct greater<experimental::propagate_const<T>>;
+ template <class T> struct less_equal<experimental::propagate_const<T>>;
+ template <class T> struct greater_equal<experimental::propagate_const<T>>;
+
+} // namespace std
+
+*/
+
+#include <__functional/operations.h>
+#include <__fwd/functional.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_pointer.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <cstddef>
+#include <experimental/__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 14
+
+_LIBCPP_BEGIN_NAMESPACE_LFTS_V2
+
+template <class _Tp>
+class propagate_const;
+
+template <class _Up>
+inline _LIBCPP_HIDE_FROM_ABI constexpr const _Up& get_underlying(const propagate_const<_Up>& __pu) _NOEXCEPT;
+
+template <class _Up>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _Up& get_underlying(propagate_const<_Up>& __pu) _NOEXCEPT;
+
+template <class _Tp>
+class propagate_const {
+public:
+ typedef remove_reference_t<decltype(*std::declval<_Tp&>())> element_type;
+
+ static_assert(!is_array<_Tp>::value, "Instantiation of propagate_const with an array type is ill-formed.");
+ static_assert(!is_reference<_Tp>::value, "Instantiation of propagate_const with a reference type is ill-formed.");
+ static_assert(!(is_pointer<_Tp>::value && is_function<__remove_pointer_t<_Tp> >::value),
+ "Instantiation of propagate_const with a function-pointer type is ill-formed.");
+ static_assert(!(is_pointer<_Tp>::value && is_same<__remove_cv_t<__remove_pointer_t<_Tp> >, void>::value),
+ "Instantiation of propagate_const with a pointer to (possibly cv-qualified) void is ill-formed.");
+
+private:
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI constexpr element_type* __get_pointer(_Up* __u) {
+ return __u;
+ }
+
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI constexpr element_type* __get_pointer(_Up& __u) {
+ return __get_pointer(__u.get());
+ }
+
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI constexpr const element_type* __get_pointer(const _Up* __u) {
+ return __u;
+ }
+
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI constexpr const element_type* __get_pointer(const _Up& __u) {
+ return __get_pointer(__u.get());
+ }
+
+ template <class _Up>
+ struct __is_propagate_const : false_type {};
+
+ template <class _Up>
+ struct __is_propagate_const<propagate_const<_Up>> : true_type {};
+
+ _Tp __t_;
+
+public:
+ template <class _Up>
+ friend constexpr const _Up& experimental::fundamentals_v2::get_underlying(const propagate_const<_Up>& __pu) _NOEXCEPT;
+ template <class _Up>
+ friend constexpr _Up& experimental::fundamentals_v2::get_underlying(propagate_const<_Up>& __pu) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr propagate_const() = default;
+
+ propagate_const(const propagate_const&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr propagate_const(propagate_const&&) = default;
+
+ template <class _Up,
+ enable_if_t<!is_convertible<_Up, _Tp>::value && is_constructible<_Tp, _Up&&>::value, bool> = true>
+ explicit _LIBCPP_HIDE_FROM_ABI constexpr propagate_const(propagate_const<_Up>&& __pu)
+ : __t_(std::move(experimental::get_underlying(__pu))) {}
+
+ template <class _Up,
+ enable_if_t<is_convertible<_Up&&, _Tp>::value && is_constructible<_Tp, _Up&&>::value, bool> = false>
+ _LIBCPP_HIDE_FROM_ABI constexpr propagate_const(propagate_const<_Up>&& __pu)
+ : __t_(std::move(experimental::get_underlying(__pu))) {}
+
+ template <class _Up,
+ enable_if_t<!is_convertible<_Up&&, _Tp>::value && is_constructible<_Tp, _Up&&>::value &&
+ !__is_propagate_const<decay_t<_Up>>::value,
+ bool> = true>
+ explicit _LIBCPP_HIDE_FROM_ABI constexpr propagate_const(_Up&& __u) : __t_(std::forward<_Up>(__u)) {}
+
+ template <class _Up,
+ enable_if_t<is_convertible<_Up&&, _Tp>::value && is_constructible<_Tp, _Up&&>::value &&
+ !__is_propagate_const<decay_t<_Up>>::value,
+ bool> = false>
+ _LIBCPP_HIDE_FROM_ABI constexpr propagate_const(_Up&& __u) : __t_(std::forward<_Up>(__u)) {}
+
+ propagate_const& operator=(const propagate_const&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr propagate_const& operator=(propagate_const&&) = default;
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr propagate_const& operator=(propagate_const<_Up>&& __pu) {
+ __t_ = std::move(experimental::get_underlying(__pu));
+ return *this;
+ }
+
+ template <class _Up, class _Vp = enable_if_t<!__is_propagate_const<decay_t<_Up>>::value>>
+ _LIBCPP_HIDE_FROM_ABI constexpr propagate_const& operator=(_Up&& __u) {
+ __t_ = std::forward<_Up>(__u);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const element_type* get() const { return __get_pointer(__t_); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr element_type* get() { return __get_pointer(__t_); }
+
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr operator bool() const { return get() != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const element_type* operator->() const { return get(); }
+
+ template <class _Dummy = _Tp, class _Up = enable_if_t<is_convertible< const _Dummy, const element_type*>::value>>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator const element_type*() const {
+ return get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const element_type& operator*() const { return *get(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr element_type* operator->() { return get(); }
+
+ template <class _Dummy = _Tp, class _Up = enable_if_t< is_convertible<_Dummy, element_type*>::value>>
+ _LIBCPP_HIDE_FROM_ABI constexpr operator element_type*() {
+ return get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr element_type& operator*() { return *get(); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr void swap(propagate_const& __pt) noexcept(__is_nothrow_swappable_v<_Tp>) {
+ using std::swap;
+ swap(__t_, __pt.__t_);
+ }
+};
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(const propagate_const<_Tp>& __pt, nullptr_t) {
+ return experimental::get_underlying(__pt) == nullptr;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(nullptr_t, const propagate_const<_Tp>& __pt) {
+ return nullptr == experimental::get_underlying(__pt);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(const propagate_const<_Tp>& __pt, nullptr_t) {
+ return experimental::get_underlying(__pt) != nullptr;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(nullptr_t, const propagate_const<_Tp>& __pt) {
+ return nullptr != experimental::get_underlying(__pt);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(const propagate_const<_Tp>& __pt, const propagate_const<_Up>& __pu) {
+ return experimental::get_underlying(__pt) == experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(const propagate_const<_Tp>& __pt, const propagate_const<_Up>& __pu) {
+ return experimental::get_underlying(__pt) != experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<(const propagate_const<_Tp>& __pt, const propagate_const<_Up>& __pu) {
+ return experimental::get_underlying(__pt) < experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>(const propagate_const<_Tp>& __pt, const propagate_const<_Up>& __pu) {
+ return experimental::get_underlying(__pt) > experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(const propagate_const<_Tp>& __pt, const propagate_const<_Up>& __pu) {
+ return experimental::get_underlying(__pt) <= experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(const propagate_const<_Tp>& __pt, const propagate_const<_Up>& __pu) {
+ return experimental::get_underlying(__pt) >= experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(const propagate_const<_Tp>& __pt, const _Up& __u) {
+ return experimental::get_underlying(__pt) == __u;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(const propagate_const<_Tp>& __pt, const _Up& __u) {
+ return experimental::get_underlying(__pt) != __u;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<(const propagate_const<_Tp>& __pt, const _Up& __u) {
+ return experimental::get_underlying(__pt) < __u;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>(const propagate_const<_Tp>& __pt, const _Up& __u) {
+ return experimental::get_underlying(__pt) > __u;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(const propagate_const<_Tp>& __pt, const _Up& __u) {
+ return experimental::get_underlying(__pt) <= __u;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(const propagate_const<_Tp>& __pt, const _Up& __u) {
+ return experimental::get_underlying(__pt) >= __u;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(const _Tp& __t, const propagate_const<_Up>& __pu) {
+ return __t == experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(const _Tp& __t, const propagate_const<_Up>& __pu) {
+ return __t != experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<(const _Tp& __t, const propagate_const<_Up>& __pu) {
+ return __t < experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>(const _Tp& __t, const propagate_const<_Up>& __pu) {
+ return __t > experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(const _Tp& __t, const propagate_const<_Up>& __pu) {
+ return __t <= experimental::get_underlying(__pu);
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(const _Tp& __t, const propagate_const<_Up>& __pu) {
+ return __t >= experimental::get_underlying(__pu);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr void
+swap(propagate_const<_Tp>& __pc1, propagate_const<_Tp>& __pc2) noexcept(__is_nothrow_swappable_v<_Tp>) {
+ __pc1.swap(__pc2);
+}
+
+template <class _Tp>
+constexpr const _Tp& get_underlying(const propagate_const<_Tp>& __pt) _NOEXCEPT {
+ return __pt.__t_;
+}
+
+template <class _Tp>
+constexpr _Tp& get_underlying(propagate_const<_Tp>& __pt) _NOEXCEPT {
+ return __pt.__t_;
+}
+
+_LIBCPP_END_NAMESPACE_LFTS_V2
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+struct hash<experimental::propagate_const<_Tp>> {
+ typedef size_t result_type;
+ typedef experimental::propagate_const<_Tp> argument_type;
+
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const experimental::propagate_const<_Tp>& __pc1) const {
+ return std::hash<_Tp>()(experimental::get_underlying(__pc1));
+ }
+};
+
+template <class _Tp>
+struct equal_to<experimental::propagate_const<_Tp>> {
+ typedef experimental::propagate_const<_Tp> first_argument_type;
+ typedef experimental::propagate_const<_Tp> second_argument_type;
+
+ _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const experimental::propagate_const<_Tp>& __pc1, const experimental::propagate_const<_Tp>& __pc2) const {
+ return std::equal_to<_Tp>()(experimental::get_underlying(__pc1), experimental::get_underlying(__pc2));
+ }
+};
+
+template <class _Tp>
+struct not_equal_to<experimental::propagate_const<_Tp>> {
+ typedef experimental::propagate_const<_Tp> first_argument_type;
+ typedef experimental::propagate_const<_Tp> second_argument_type;
+
+ _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const experimental::propagate_const<_Tp>& __pc1, const experimental::propagate_const<_Tp>& __pc2) const {
+ return std::not_equal_to<_Tp>()(experimental::get_underlying(__pc1), experimental::get_underlying(__pc2));
+ }
+};
+
+template <class _Tp>
+struct less<experimental::propagate_const<_Tp>> {
+ typedef experimental::propagate_const<_Tp> first_argument_type;
+ typedef experimental::propagate_const<_Tp> second_argument_type;
+
+ _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const experimental::propagate_const<_Tp>& __pc1, const experimental::propagate_const<_Tp>& __pc2) const {
+ return std::less<_Tp>()(experimental::get_underlying(__pc1), experimental::get_underlying(__pc2));
+ }
+};
+
+template <class _Tp>
+struct greater<experimental::propagate_const<_Tp>> {
+ typedef experimental::propagate_const<_Tp> first_argument_type;
+ typedef experimental::propagate_const<_Tp> second_argument_type;
+
+ _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const experimental::propagate_const<_Tp>& __pc1, const experimental::propagate_const<_Tp>& __pc2) const {
+ return std::greater<_Tp>()(experimental::get_underlying(__pc1), experimental::get_underlying(__pc2));
+ }
+};
+
+template <class _Tp>
+struct less_equal<experimental::propagate_const<_Tp>> {
+ typedef experimental::propagate_const<_Tp> first_argument_type;
+ typedef experimental::propagate_const<_Tp> second_argument_type;
+
+ _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const experimental::propagate_const<_Tp>& __pc1, const experimental::propagate_const<_Tp>& __pc2) const {
+ return std::less_equal<_Tp>()(experimental::get_underlying(__pc1), experimental::get_underlying(__pc2));
+ }
+};
+
+template <class _Tp>
+struct greater_equal<experimental::propagate_const<_Tp>> {
+ typedef experimental::propagate_const<_Tp> first_argument_type;
+ typedef experimental::propagate_const<_Tp> second_argument_type;
+
+ _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const experimental::propagate_const<_Tp>& __pc1, const experimental::propagate_const<_Tp>& __pc2) const {
+ return std::greater_equal<_Tp>()(experimental::get_underlying(__pc1), experimental::get_underlying(__pc2));
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_EXPERIMENTAL_PROPAGATE_CONST
diff --git a/libcxx/include/__cxx03/experimental/simd b/libcxx/include/__cxx03/experimental/simd
new file mode 100644
index 00000000000000..484543b81daf1f
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/simd
@@ -0,0 +1,88 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL_SIMD
+#define _LIBCPP_EXPERIMENTAL_SIMD
+
+/*
+ experimental/simd synopsis
+
+namespace std::experimental {
+inline namespace parallelism_v2 {
+ namespace simd_abi {
+ using scalar = see below;
+ template<int N> using fixed_size = see below;
+ template<class T> inline constexpr int max_fixed_size = implementation-defined;
+ template<class T> using compatible = implementation-defined;
+ template<class T> using native = implementation-defined;
+
+ template<class T, size_t N, class... Abis> struct deduce { using type = see below; };
+ template<class T, size_t N, class... Abis> using deduce_t =
+ typename deduce<T, N, Abis...>::type;
+ } // namespace simd_abi
+
+ // class template simd [simd.class]
+ template <class T, class Abi = simd_abi::compatible<T>> class simd;
+ template <class T> using native_simd = simd<T, simd_abi::native<T>>;
+ template <class T, int N> using fixed_size_simd = simd<T, simd_abi::fixed_size<N>>;
+
+ // class template simd_mask [simd.mask.class]
+ template <class T, class Abi = simd_abi::compatible<T>> class simd_mask;
+ template <class T> using native_simd_mask = simd_mask<T, simd_abi::native<T>>;
+ template <class T, int N> using fixed_size_simd_mask = simd_mask<T, simd_abi::fixed_size<N>>;
+
+ // memory alignment
+ struct element_aligned_tag {};
+ struct vector_aligned_tag {};
+ template <size_t> struct overaligned_tag {};
+ inline constexpr element_aligned_tag element_aligned{};
+ inline constexpr vector_aligned_tag vector_aligned{};
+ template <size_t N> inline constexpr overaligned_tag<N> overaligned{};
+
+ // traits [simd.traits]
+ template<class T> struct is_abi_tag;
+ template<class T> inline constexpr bool is_abi_tag_v = is_abi_tag<T>::value;
+
+ template <class T> struct is_simd;
+ template <class T> inline constexpr bool is_simd_v = is_simd<T>::value;
+
+ template <class T> struct is_simd_mask;
+ template <class T> inline constexpr bool is_simd_mask_v = is_simd_mask<T>::value;
+
+ template<class T> struct is_simd_flag_type;
+ template<class T> inline constexpr bool is_simd_flag_type_v = is_simd_flag_type<T>::value;
+
+ template<class T, class Abi = simd_abi::compatible<T>> struct simd_size;
+ template<class T, class Abi = simd_abi::compatible<T>>
+ inline constexpr size_t simd_size_v = simd_size<T,Abi>::value;
+
+ template<class T, class U = typename T::value_type> struct memory_alignment;
+ template<class T, class U = typename T::value_type>
+ inline constexpr size_t memory_alignment_v = memory_alignment<T,U>::value;
+
+} // namespace parallelism_v2
+} // namespace std::experimental
+
+*/
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#include <experimental/__config>
+#include <experimental/__simd/aligned_tag.h>
+#include <experimental/__simd/declaration.h>
+#include <experimental/__simd/reference.h>
+#include <experimental/__simd/scalar.h>
+#include <experimental/__simd/simd.h>
+#include <experimental/__simd/simd_mask.h>
+#include <experimental/__simd/traits.h>
+#include <experimental/__simd/vec_ext.h>
+
+#endif /* _LIBCPP_EXPERIMENTAL_SIMD */
diff --git a/libcxx/include/__cxx03/experimental/type_traits b/libcxx/include/__cxx03/experimental/type_traits
new file mode 100644
index 00000000000000..31b041bc94c43a
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/type_traits
@@ -0,0 +1,153 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL_TYPE_TRAITS
+#define _LIBCPP_EXPERIMENTAL_TYPE_TRAITS
+
+/**
+ experimental/type_traits synopsis
+
+// C++1y
+#include <type_traits>
+
+namespace std {
+namespace experimental {
+inline namespace fundamentals_v1 {
+
+ // 3.3.2, Other type transformations
+ template <class> class invocation_type; // not defined
+ template <class F, class... ArgTypes> class invocation_type<F(ArgTypes...)>;
+ template <class> class raw_invocation_type; // not defined
+ template <class F, class... ArgTypes> class raw_invocation_type<F(ArgTypes...)>;
+
+ template <class T>
+ using invocation_type_t = typename invocation_type<T>::type;
+ template <class T>
+ using raw_invocation_type_t = typename raw_invocation_type<T>::type;
+
+ // 3.3.4, Detection idiom
+ template <class...> using void_t = void;
+
+ struct nonesuch {
+ nonesuch() = delete;
+ ~nonesuch() = delete;
+ nonesuch(nonesuch const&) = delete;
+ void operator=(nonesuch const&) = delete;
+ };
+
+ template <template<class...> class Op, class... Args>
+ using is_detected = see below;
+ template <template<class...> class Op, class... Args>
+ constexpr bool is_detected_v = is_detected<Op, Args...>::value;
+ template <template<class...> class Op, class... Args>
+ using detected_t = see below;
+ template <class Default, template<class...> class Op, class... Args>
+ using detected_or = see below;
+ template <class Default, template<class...> class Op, class... Args>
+ using detected_or_t = typename detected_or<Default, Op, Args...>::type;
+ template <class Expected, template<class...> class Op, class... Args>
+ using is_detected_exact = is_same<Expected, detected_t<Op, Args...>>;
+ template <class Expected, template<class...> class Op, class... Args>
+ constexpr bool is_detected_exact_v
+ = is_detected_exact<Expected, Op, Args...>::value;
+ template <class To, template<class...> class Op, class... Args>
+ using is_detected_convertible = is_convertible<detected_t<Op, Args...>, To>;
+ template <class To, template<class...> class Op, class... Args>
+ constexpr bool is_detected_convertible_v
+ = is_detected_convertible<To, Op, Args...>::value;
+
+} // namespace fundamentals_v1
+} // namespace experimental
+} // namespace std
+
+ */
+
+#include <experimental/__config>
+
+#if _LIBCPP_STD_VER >= 14
+
+# include <initializer_list>
+# include <type_traits>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_LFTS
+
+// 3.3.2, Other type transformations
+/*
+template <class>
+class _LIBCPP_TEMPLATE_VIS raw_invocation_type;
+
+template <class _Fn, class ..._Args>
+class _LIBCPP_TEMPLATE_VIS raw_invocation_type<_Fn(_Args...)>;
+
+template <class>
+class _LIBCPP_TEMPLATE_VIS invokation_type;
+
+template <class _Fn, class ..._Args>
+class _LIBCPP_TEMPLATE_VIS invokation_type<_Fn(_Args...)>;
+
+template <class _Tp>
+using invokation_type_t = typename invokation_type<_Tp>::type;
+
+template <class _Tp>
+using raw_invocation_type_t = typename raw_invocation_type<_Tp>::type;
+*/
+
+// 3.3.4, Detection idiom
+template <class...>
+using void_t = void;
+
+struct nonesuch : private __nat { // make nonesuch "not an aggregate"
+ ~nonesuch() = delete;
+ nonesuch(nonesuch const&) = delete;
+ void operator=(nonesuch const&) = delete;
+};
+
+template <class _Default, class _AlwaysVoid, template <class...> class _Op, class... _Args>
+struct _DETECTOR {
+ using value_t = false_type;
+ using type = _Default;
+};
+
+template <class _Default, template <class...> class _Op, class... _Args>
+struct _DETECTOR<_Default, void_t<_Op<_Args...>>, _Op, _Args...> {
+ using value_t = true_type;
+ using type = _Op<_Args...>;
+};
+
+template <template <class...> class _Op, class... _Args>
+using is_detected = typename _DETECTOR<nonesuch, void, _Op, _Args...>::value_t;
+template <template <class...> class _Op, class... _Args>
+using detected_t = typename _DETECTOR<nonesuch, void, _Op, _Args...>::type;
+template <template <class...> class _Op, class... _Args>
+constexpr bool is_detected_v = is_detected<_Op, _Args...>::value;
+
+template <class _Default, template <class...> class _Op, class... _Args>
+using detected_or = _DETECTOR<_Default, void, _Op, _Args...>;
+template <class _Default, template <class...> class _Op, class... _Args>
+using detected_or_t = typename detected_or<_Default, _Op, _Args...>::type;
+
+template <class _Expected, template <class...> class _Op, class... _Args>
+using is_detected_exact = is_same<_Expected, detected_t<_Op, _Args...>>;
+template <class _Expected, template <class...> class _Op, class... _Args>
+constexpr bool is_detected_exact_v = is_detected_exact<_Expected, _Op, _Args...>::value;
+
+template <class _To, template <class...> class _Op, class... _Args>
+using is_detected_convertible = is_convertible<detected_t<_Op, _Args...>, _To>;
+template <class _To, template <class...> class _Op, class... _Args>
+constexpr bool is_detected_convertible_v = is_detected_convertible<_To, _Op, _Args...>::value;
+
+_LIBCPP_END_NAMESPACE_LFTS
+
+#endif /* _LIBCPP_STD_VER >= 14 */
+
+#endif /* _LIBCPP_EXPERIMENTAL_TYPE_TRAITS */
diff --git a/libcxx/include/__cxx03/experimental/utility b/libcxx/include/__cxx03/experimental/utility
new file mode 100644
index 00000000000000..8bd0a055b7783f
--- /dev/null
+++ b/libcxx/include/__cxx03/experimental/utility
@@ -0,0 +1,46 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL_UTILITY
+#define _LIBCPP_EXPERIMENTAL_UTILITY
+
+/*
+ experimental/utility synopsis
+
+// C++1y
+
+#include <utility>
+
+namespace std {
+namespace experimental {
+inline namespace fundamentals_v1 {
+
+ 3.1.2, erased-type placeholder
+ struct erased_type { };
+
+} // namespace fundamentals_v1
+} // namespace experimental
+} // namespace std
+
+ */
+
+#include <experimental/__config>
+#include <utility>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_LFTS
+
+struct _LIBCPP_TEMPLATE_VIS erased_type {};
+
+_LIBCPP_END_NAMESPACE_LFTS
+
+#endif /* _LIBCPP_EXPERIMENTAL_UTILITY */
diff --git a/libcxx/include/__cxx03/ext/__hash b/libcxx/include/__cxx03/ext/__hash
new file mode 100644
index 00000000000000..67f7e351756fb0
--- /dev/null
+++ b/libcxx/include/__cxx03/ext/__hash
@@ -0,0 +1,85 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXT_HASH
+#define _LIBCPP_EXT_HASH
+
+#pragma GCC system_header
+
+#include <__config>
+#include <cstring>
+#include <stddef.h>
+#include <string>
+
+namespace __gnu_cxx {
+
+template <typename _Tp>
+struct _LIBCPP_TEMPLATE_VIS hash {};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<const char*> : public std::__unary_function<const char*, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const char* __c) const _NOEXCEPT {
+ return std::__do_string_hash(__c, __c + strlen(__c));
+ }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<char*> : public std::__unary_function<char*, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(char* __c) const _NOEXCEPT {
+ return std::__do_string_hash<const char*>(__c, __c + strlen(__c));
+ }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<char> : public std::__unary_function<char, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(char __c) const _NOEXCEPT { return __c; }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<signed char> : public std::__unary_function<signed char, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(signed char __c) const _NOEXCEPT { return __c; }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned char> : public std::__unary_function<unsigned char, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(unsigned char __c) const _NOEXCEPT { return __c; }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<short> : public std::__unary_function<short, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(short __c) const _NOEXCEPT { return __c; }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned short> : public std::__unary_function<unsigned short, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(unsigned short __c) const _NOEXCEPT { return __c; }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<int> : public std::__unary_function<int, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(int __c) const _NOEXCEPT { return __c; }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned int> : public std::__unary_function<unsigned int, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(unsigned int __c) const _NOEXCEPT { return __c; }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<long> : public std::__unary_function<long, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(long __c) const _NOEXCEPT { return __c; }
+};
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<unsigned long> : public std::__unary_function<unsigned long, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(unsigned long __c) const _NOEXCEPT { return __c; }
+};
+} // namespace __gnu_cxx
+
+#endif // _LIBCPP_EXT_HASH
diff --git a/libcxx/include/__cxx03/ext/hash_map b/libcxx/include/__cxx03/ext/hash_map
new file mode 100644
index 00000000000000..7b5b31c4081788
--- /dev/null
+++ b/libcxx/include/__cxx03/ext/hash_map
@@ -0,0 +1,872 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_HASH_MAP
+#define _LIBCPP_HASH_MAP
+
+/*
+
+ hash_map synopsis
+
+namespace __gnu_cxx
+{
+
+template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
+ class Alloc = allocator<pair<const Key, T>>>
+class hash_map
+{
+public:
+ // types
+ typedef Key key_type;
+ typedef T mapped_type;
+ typedef Hash hasher;
+ typedef Pred key_equal;
+ typedef Alloc allocator_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef /unspecified/ iterator;
+ typedef /unspecified/ const_iterator;
+
+ hash_map();
+ explicit hash_map(size_type n, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template <class InputIterator>
+ hash_map(InputIterator f, InputIterator l);
+ template <class InputIterator>
+ hash_map(InputIterator f, InputIterator l,
+ size_type n, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ hash_map(const hash_map&);
+ ~hash_map();
+ hash_map& operator=(const hash_map&);
+
+ allocator_type get_allocator() const;
+
+ bool empty() const;
+ size_type size() const;
+ size_type max_size() const;
+
+ iterator begin();
+ iterator end();
+ const_iterator begin() const;
+ const_iterator end() const;
+
+ pair<iterator, bool> insert(const value_type& obj);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+
+ void erase(const_iterator position);
+ size_type erase(const key_type& k);
+ void erase(const_iterator first, const_iterator last);
+ void clear();
+
+ void swap(hash_map&);
+
+ hasher hash_funct() const;
+ key_equal key_eq() const;
+
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ size_type count(const key_type& k) const;
+ pair<iterator, iterator> equal_range(const key_type& k);
+ pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
+
+ mapped_type& operator[](const key_type& k);
+
+ size_type bucket_count() const;
+ size_type max_bucket_count() const;
+
+ size_type elems_in_bucket(size_type n) const;
+
+ void resize(size_type n);
+};
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ void swap(hash_map<Key, T, Hash, Pred, Alloc>& x,
+ hash_map<Key, T, Hash, Pred, Alloc>& y);
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ bool
+ operator==(const hash_map<Key, T, Hash, Pred, Alloc>& x,
+ const hash_map<Key, T, Hash, Pred, Alloc>& y);
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ bool
+ operator!=(const hash_map<Key, T, Hash, Pred, Alloc>& x,
+ const hash_map<Key, T, Hash, Pred, Alloc>& y);
+
+template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
+ class Alloc = allocator<pair<const Key, T>>>
+class hash_multimap
+{
+public:
+ // types
+ typedef Key key_type;
+ typedef T mapped_type;
+ typedef Hash hasher;
+ typedef Pred key_equal;
+ typedef Alloc allocator_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef /unspecified/ iterator;
+ typedef /unspecified/ const_iterator;
+
+ explicit hash_multimap(size_type n = 193, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template <class InputIterator>
+ hash_multimap(InputIterator f, InputIterator l,
+ size_type n = 193, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ explicit hash_multimap(const allocator_type&);
+ hash_multimap(const hash_multimap&);
+ ~hash_multimap();
+ hash_multimap& operator=(const hash_multimap&);
+
+ allocator_type get_allocator() const;
+
+ bool empty() const;
+ size_type size() const;
+ size_type max_size() const;
+
+ iterator begin();
+ iterator end();
+ const_iterator begin() const;
+ const_iterator end() const;
+
+ iterator insert(const value_type& obj);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+
+ void erase(const_iterator position);
+ size_type erase(const key_type& k);
+ void erase(const_iterator first, const_iterator last);
+ void clear();
+
+ void swap(hash_multimap&);
+
+ hasher hash_funct() const;
+ key_equal key_eq() const;
+
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ size_type count(const key_type& k) const;
+ pair<iterator, iterator> equal_range(const key_type& k);
+ pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
+
+ size_type bucket_count() const;
+ size_type max_bucket_count() const;
+
+ size_type elems_in_bucket(size_type n) const;
+
+ void resize(size_type n);
+};
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ void swap(hash_multimap<Key, T, Hash, Pred, Alloc>& x,
+ hash_multimap<Key, T, Hash, Pred, Alloc>& y);
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ bool
+ operator==(const hash_multimap<Key, T, Hash, Pred, Alloc>& x,
+ const hash_multimap<Key, T, Hash, Pred, Alloc>& y);
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ bool
+ operator!=(const hash_multimap<Key, T, Hash, Pred, Alloc>& x,
+ const hash_multimap<Key, T, Hash, Pred, Alloc>& y);
+
+} // __gnu_cxx
+
+*/
+
+#include <__config>
+#include <__hash_table>
+#include <algorithm>
+#include <ext/__hash>
+#include <functional>
+
+#if defined(__DEPRECATED) && __DEPRECATED
+# if defined(_LIBCPP_WARNING)
+_LIBCPP_WARNING("Use of the header <ext/hash_map> is deprecated. Migrate to <unordered_map>")
+# else
+# warning Use of the header <ext/hash_map> is deprecated. Migrate to <unordered_map>
+# endif
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+namespace __gnu_cxx {
+
+template <class _Tp, class _Hash, bool = std::is_empty<_Hash>::value && !std::__libcpp_is_final<_Hash>::value >
+class __hash_map_hasher : private _Hash {
+public:
+ _LIBCPP_HIDE_FROM_ABI __hash_map_hasher() : _Hash() {}
+ _LIBCPP_HIDE_FROM_ABI __hash_map_hasher(const _Hash& __h) : _Hash(__h) {}
+ _LIBCPP_HIDE_FROM_ABI const _Hash& hash_function() const { return *this; }
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const _Tp& __x) const { return static_cast<const _Hash&>(*this)(__x.first); }
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const typename _Tp::first_type& __x) const {
+ return static_cast<const _Hash&>(*this)(__x);
+ }
+};
+
+template <class _Tp, class _Hash>
+class __hash_map_hasher<_Tp, _Hash, false> {
+ _Hash __hash_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __hash_map_hasher() : __hash_() {}
+ _LIBCPP_HIDE_FROM_ABI __hash_map_hasher(const _Hash& __h) : __hash_(__h) {}
+ _LIBCPP_HIDE_FROM_ABI const _Hash& hash_function() const { return __hash_; }
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const _Tp& __x) const { return __hash_(__x.first); }
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const typename _Tp::first_type& __x) const { return __hash_(__x); }
+};
+
+template <class _Tp, class _Pred, bool = std::is_empty<_Pred>::value && !std::__libcpp_is_final<_Pred>::value >
+class __hash_map_equal : private _Pred {
+public:
+ _LIBCPP_HIDE_FROM_ABI __hash_map_equal() : _Pred() {}
+ _LIBCPP_HIDE_FROM_ABI __hash_map_equal(const _Pred& __p) : _Pred(__p) {}
+ _LIBCPP_HIDE_FROM_ABI const _Pred& key_eq() const { return *this; }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const {
+ return static_cast<const _Pred&>(*this)(__x.first, __y.first);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const typename _Tp::first_type& __x, const _Tp& __y) const {
+ return static_cast<const _Pred&>(*this)(__x, __y.first);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const typename _Tp::first_type& __y) const {
+ return static_cast<const _Pred&>(*this)(__x.first, __y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const typename _Tp::first_type& __x, const typename _Tp::first_type& __y) const {
+ return static_cast<const _Pred&>(*this)(__x, __y);
+ }
+};
+
+template <class _Tp, class _Pred>
+class __hash_map_equal<_Tp, _Pred, false> {
+ _Pred __pred_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __hash_map_equal() : __pred_() {}
+ _LIBCPP_HIDE_FROM_ABI __hash_map_equal(const _Pred& __p) : __pred_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI const _Pred& key_eq() const { return __pred_; }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const _Tp& __y) const { return __pred_(__x.first, __y.first); }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const typename _Tp::first_type& __x, const _Tp& __y) const {
+ return __pred_(__x, __y.first);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Tp& __x, const typename _Tp::first_type& __y) const {
+ return __pred_(__x.first, __y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool
+ operator()(const typename _Tp::first_type& __x, const typename _Tp::first_type& __y) const {
+ return __pred_(__x, __y);
+ }
+};
+
+template <class _Alloc>
+class __hash_map_node_destructor {
+ typedef _Alloc allocator_type;
+ typedef std::allocator_traits<allocator_type> __alloc_traits;
+ typedef typename __alloc_traits::value_type::__node_value_type value_type;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+
+private:
+ typedef typename value_type::first_type first_type;
+ typedef typename value_type::second_type second_type;
+
+ allocator_type& __na_;
+
+public:
+ bool __first_constructed;
+ bool __second_constructed;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_node_destructor(__hash_map_node_destructor const&) = default;
+ __hash_map_node_destructor& operator=(const __hash_map_node_destructor&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_map_node_destructor(allocator_type& __na)
+ : __na_(__na), __first_constructed(false), __second_constructed(false) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __hash_map_node_destructor(std::__hash_node_destructor<allocator_type>&& __x)
+ : __na_(__x.__na_), __first_constructed(__x.__value_constructed), __second_constructed(__x.__value_constructed) {
+ __x.__value_constructed = false;
+ }
+#else // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __hash_map_node_destructor(const std::__hash_node_destructor<allocator_type>& __x)
+ : __na_(__x.__na_), __first_constructed(__x.__value_constructed), __second_constructed(__x.__value_constructed) {
+ const_cast<bool&>(__x.__value_constructed) = false;
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI void operator()(pointer __p) {
+ if (__second_constructed)
+ __alloc_traits::destroy(__na_, std::addressof(__p->__get_value().second));
+ if (__first_constructed)
+ __alloc_traits::destroy(__na_, std::addressof(__p->__get_value().first));
+ if (__p)
+ __alloc_traits::deallocate(__na_, __p, 1);
+ }
+};
+
+template <class _HashIterator>
+class _LIBCPP_TEMPLATE_VIS __hash_map_iterator {
+ _HashIterator __i_;
+
+ typedef const typename _HashIterator::value_type::first_type key_type;
+ typedef typename _HashIterator::value_type::second_type mapped_type;
+
+public:
+ typedef std::forward_iterator_tag iterator_category;
+ typedef std::pair<key_type, mapped_type> value_type;
+ typedef typename _HashIterator::difference_type difference_type;
+ typedef value_type& reference;
+ typedef std::__rebind_pointer_t<typename _HashIterator::pointer, value_type> pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_iterator() {}
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_iterator(_HashIterator __i) : __i_(__i) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return *operator->(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return (pointer)__i_.operator->(); }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_iterator& operator++() {
+ ++__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __hash_map_iterator operator++(int) {
+ __hash_map_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __hash_map_iterator& __x, const __hash_map_iterator& __y) {
+ return __x.__i_ == __y.__i_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __hash_map_iterator& __x, const __hash_map_iterator& __y) {
+ return __x.__i_ != __y.__i_;
+ }
+
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS hash_map;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS hash_multimap;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
+};
+
+template <class _HashIterator>
+class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator {
+ _HashIterator __i_;
+
+ typedef const typename _HashIterator::value_type::first_type key_type;
+ typedef typename _HashIterator::value_type::second_type mapped_type;
+
+public:
+ typedef std::forward_iterator_tag iterator_category;
+ typedef std::pair<key_type, mapped_type> value_type;
+ typedef typename _HashIterator::difference_type difference_type;
+ typedef const value_type& reference;
+ typedef std::__rebind_pointer_t<typename _HashIterator::pointer, const value_type> pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator() {}
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator(_HashIterator __i) : __i_(__i) {}
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator(__hash_map_iterator<typename _HashIterator::__non_const_iterator> __i)
+ : __i_(__i.__i_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return *operator->(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return (pointer)__i_.operator->(); }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator& operator++() {
+ ++__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator operator++(int) {
+ __hash_map_const_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y) {
+ return __x.__i_ == __y.__i_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y) {
+ return __x.__i_ != __y.__i_;
+ }
+
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS hash_map;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS hash_multimap;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
+};
+
+template <class _Key,
+ class _Tp,
+ class _Hash = hash<_Key>,
+ class _Pred = std::equal_to<_Key>,
+ class _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
+class _LIBCPP_TEMPLATE_VIS hash_map {
+public:
+ // types
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef _Tp data_type;
+ typedef _Hash hasher;
+ typedef _Pred key_equal;
+ typedef _Alloc allocator_type;
+ typedef std::pair<const key_type, mapped_type> value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+
+private:
+ typedef std::pair<key_type, mapped_type> __value_type;
+ typedef __hash_map_hasher<__value_type, hasher> __hasher;
+ typedef __hash_map_equal<__value_type, key_equal> __key_equal;
+ typedef std::__rebind_alloc<std::allocator_traits<allocator_type>, __value_type> __allocator_type;
+
+ typedef std::__hash_table<__value_type, __hasher, __key_equal, __allocator_type> __table;
+
+ __table __table_;
+
+ typedef typename __table::__node_pointer __node_pointer;
+ typedef typename __table::__node_const_pointer __node_const_pointer;
+ typedef typename __table::__node_traits __node_traits;
+ typedef typename __table::__node_allocator __node_allocator;
+ typedef typename __table::__node __node;
+ typedef __hash_map_node_destructor<__node_allocator> _Dp;
+ typedef std::unique_ptr<__node, _Dp> __node_holder;
+ typedef std::allocator_traits<allocator_type> __alloc_traits;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+ typedef typename __alloc_traits::size_type size_type;
+ typedef typename __alloc_traits::difference_type difference_type;
+
+ typedef __hash_map_iterator<typename __table::iterator> iterator;
+ typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI hash_map() {}
+ explicit _LIBCPP_HIDE_FROM_ABI
+ hash_map(size_type __n, const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI hash_map(size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI hash_map(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ hash_map(_InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ hash_map(_InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI hash_map(const hash_map& __u);
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const { return allocator_type(__table_.__node_alloc()); }
+
+ _LIBCPP_HIDE_FROM_ABI bool empty() const { return __table_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const { return __table_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const { return __table_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const { return __table_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI std::pair<iterator, bool> insert(const value_type& __x) {
+ return __table_.__insert_unique(__x);
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, const value_type& __x) { return insert(__x).first; }
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last);
+
+ _LIBCPP_HIDE_FROM_ABI void erase(const_iterator __p) { __table_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __table_.__erase_unique(__k); }
+ _LIBCPP_HIDE_FROM_ABI void erase(const_iterator __first, const_iterator __last) {
+ __table_.erase(__first.__i_, __last.__i_);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear() { __table_.clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(hash_map& __u) { __table_.swap(__u.__table_); }
+
+ _LIBCPP_HIDE_FROM_ABI hasher hash_funct() const { return __table_.hash_function().hash_function(); }
+ _LIBCPP_HIDE_FROM_ABI key_equal key_eq() const { return __table_.key_eq().key_eq(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __table_.__count_unique(__k); }
+ _LIBCPP_HIDE_FROM_ABI std::pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __table_.__equal_range_unique(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI std::pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __table_.__equal_range_unique(__k);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI mapped_type& operator[](const key_type& __k);
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const { return __table_.bucket_count(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const { return __table_.max_bucket_count(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type elems_in_bucket(size_type __n) const { return __table_.bucket_size(__n); }
+
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n) { __table_.__rehash_unique(__n); }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI __node_holder __construct_node(const key_type& __k);
+};
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
+ size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_unique(__n);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(_InputIterator __first, _InputIterator __last) {
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_unique(__n);
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(const hash_map& __u) : __table_(__u.__table_) {
+ __table_.__rehash_unique(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+typename hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
+hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(const key_type& __k) {
+ __node_allocator& __na = __table_.__node_alloc();
+ __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
+ __node_traits::construct(__na, std::addressof(__h->__get_value().first), __k);
+ __h.get_deleter().__first_constructed = true;
+ __node_traits::construct(__na, std::addressof(__h->__get_value().second));
+ __h.get_deleter().__second_constructed = true;
+ return __h;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+inline void hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first, _InputIterator __last) {
+ for (; __first != __last; ++__first)
+ __table_.__insert_unique(*__first);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_Tp& hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k) {
+ iterator __i = find(__k);
+ if (__i != end())
+ return __i->second;
+ __node_holder __h = __construct_node(__k);
+ std::pair<iterator, bool> __r = __table_.__node_insert_unique(__h.get());
+ __h.release();
+ return __r.first->second;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ __x.swap(__y);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool
+operator==(const hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, const hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ if (__x.size() != __y.size())
+ return false;
+ typedef typename hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator const_iterator;
+ for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end(); __i != __ex; ++__i) {
+ const_iterator __j = __y.find(__i->first);
+ if (__j == __ey || !(*__i == *__j))
+ return false;
+ }
+ return true;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, const hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Key,
+ class _Tp,
+ class _Hash = hash<_Key>,
+ class _Pred = std::equal_to<_Key>,
+ class _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
+class _LIBCPP_TEMPLATE_VIS hash_multimap {
+public:
+ // types
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef _Tp data_type;
+ typedef _Hash hasher;
+ typedef _Pred key_equal;
+ typedef _Alloc allocator_type;
+ typedef std::pair<const key_type, mapped_type> value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+
+private:
+ typedef std::pair<key_type, mapped_type> __value_type;
+ typedef __hash_map_hasher<__value_type, hasher> __hasher;
+ typedef __hash_map_equal<__value_type, key_equal> __key_equal;
+ typedef std::__rebind_alloc<std::allocator_traits<allocator_type>, __value_type> __allocator_type;
+
+ typedef std::__hash_table<__value_type, __hasher, __key_equal, __allocator_type> __table;
+
+ __table __table_;
+
+ typedef typename __table::__node_traits __node_traits;
+ typedef typename __table::__node_allocator __node_allocator;
+ typedef typename __table::__node __node;
+ typedef __hash_map_node_destructor<__node_allocator> _Dp;
+ typedef std::unique_ptr<__node, _Dp> __node_holder;
+ typedef std::allocator_traits<allocator_type> __alloc_traits;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+ typedef typename __alloc_traits::size_type size_type;
+ typedef typename __alloc_traits::difference_type difference_type;
+
+ typedef __hash_map_iterator<typename __table::iterator> iterator;
+ typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI hash_multimap() {}
+ explicit _LIBCPP_HIDE_FROM_ABI
+ hash_multimap(size_type __n, const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI
+ hash_multimap(size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI hash_multimap(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ hash_multimap(_InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI hash_multimap(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI hash_multimap(const hash_multimap& __u);
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const { return allocator_type(__table_.__node_alloc()); }
+
+ _LIBCPP_HIDE_FROM_ABI bool empty() const { return __table_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const { return __table_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const { return __table_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const { return __table_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const value_type& __x) { return __table_.__insert_multi(__x); }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, const value_type& __x) { return insert(__x); }
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last);
+
+ _LIBCPP_HIDE_FROM_ABI void erase(const_iterator __p) { __table_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __table_.__erase_multi(__k); }
+ _LIBCPP_HIDE_FROM_ABI void erase(const_iterator __first, const_iterator __last) {
+ __table_.erase(__first.__i_, __last.__i_);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear() { __table_.clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(hash_multimap& __u) { __table_.swap(__u.__table_); }
+
+ _LIBCPP_HIDE_FROM_ABI hasher hash_funct() const { return __table_.hash_function().hash_function(); }
+ _LIBCPP_HIDE_FROM_ABI key_equal key_eq() const { return __table_.key_eq().key_eq(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __table_.__count_multi(__k); }
+ _LIBCPP_HIDE_FROM_ABI std::pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __table_.__equal_range_multi(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI std::pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __table_.__equal_range_multi(__k);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const { return __table_.bucket_count(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const { return __table_.max_bucket_count(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type elems_in_bucket(size_type __n) const { return __table_.bucket_size(__n); }
+
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n) { __table_.__rehash_multi(__n); }
+};
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
+ size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_multi(__n);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(_InputIterator __first, _InputIterator __last) {
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_multi(__n);
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(const hash_multimap& __u) : __table_(__u.__table_) {
+ __table_.__rehash_multi(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+inline void hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first, _InputIterator __last) {
+ for (; __first != __last; ++__first)
+ __table_.__insert_multi(*__first);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ __x.swap(__y);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
+ const hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ if (__x.size() != __y.size())
+ return false;
+ typedef typename hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator const_iterator;
+ typedef std::pair<const_iterator, const_iterator> _EqRng;
+ for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;) {
+ _EqRng __xeq = __x.equal_range(__i->first);
+ _EqRng __yeq = __y.equal_range(__i->first);
+ if (std::distance(__xeq.first, __xeq.second) != std::distance(__yeq.first, __yeq.second) ||
+ !std::is_permutation(__xeq.first, __xeq.second, __yeq.first))
+ return false;
+ __i = __xeq.second;
+ }
+ return true;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
+ const hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+} // namespace __gnu_cxx
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <iterator>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_HASH_MAP
diff --git a/libcxx/include/__cxx03/ext/hash_set b/libcxx/include/__cxx03/ext/hash_set
new file mode 100644
index 00000000000000..1ab259b59979f3
--- /dev/null
+++ b/libcxx/include/__cxx03/ext/hash_set
@@ -0,0 +1,584 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_HASH_SET
+#define _LIBCPP_HASH_SET
+
+/*
+
+ hash_set synopsis
+
+namespace __gnu_cxx
+{
+
+template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
+ class Alloc = allocator<Value>>
+class hash_set
+{
+public:
+ // types
+ typedef Value key_type;
+ typedef key_type value_type;
+ typedef Hash hasher;
+ typedef Pred key_equal;
+ typedef Alloc allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef /unspecified/ iterator;
+ typedef /unspecified/ const_iterator;
+
+ explicit hash_set(size_type n = 193, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template <class InputIterator>
+ hash_set(InputIterator f, InputIterator l,
+ size_type n = 193, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ hash_set(const hash_set&);
+ ~hash_set();
+ hash_set& operator=(const hash_set&);
+
+ allocator_type get_allocator() const;
+
+ bool empty() const;
+ size_type size() const;
+ size_type max_size() const;
+
+ iterator begin();
+ iterator end();
+ const_iterator begin() const;
+ const_iterator end() const;
+
+ pair<iterator, bool> insert(const value_type& obj);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+
+ void erase(const_iterator position);
+ size_type erase(const key_type& k);
+ void erase(const_iterator first, const_iterator last);
+ void clear();
+
+ void swap(hash_set&);
+
+ hasher hash_funct() const;
+ key_equal key_eq() const;
+
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ size_type count(const key_type& k) const;
+ pair<iterator, iterator> equal_range(const key_type& k);
+ pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
+
+ size_type bucket_count() const;
+ size_type max_bucket_count() const;
+
+ size_type elems_in_bucket(size_type n) const;
+
+ void resize(size_type n);
+};
+
+template <class Value, class Hash, class Pred, class Alloc>
+ void swap(hash_set<Value, Hash, Pred, Alloc>& x,
+ hash_set<Value, Hash, Pred, Alloc>& y);
+
+template <class Value, class Hash, class Pred, class Alloc>
+ bool
+ operator==(const hash_set<Value, Hash, Pred, Alloc>& x,
+ const hash_set<Value, Hash, Pred, Alloc>& y);
+
+template <class Value, class Hash, class Pred, class Alloc>
+ bool
+ operator!=(const hash_set<Value, Hash, Pred, Alloc>& x,
+ const hash_set<Value, Hash, Pred, Alloc>& y);
+
+template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
+ class Alloc = allocator<Value>>
+class hash_multiset
+{
+public:
+ // types
+ typedef Value key_type;
+ typedef key_type value_type;
+ typedef Hash hasher;
+ typedef Pred key_equal;
+ typedef Alloc allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef /unspecified/ iterator;
+ typedef /unspecified/ const_iterator;
+
+ explicit hash_multiset(size_type n = 193, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template <class InputIterator>
+ hash_multiset(InputIterator f, InputIterator l,
+ size_type n = 193, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ hash_multiset(const hash_multiset&);
+ ~hash_multiset();
+ hash_multiset& operator=(const hash_multiset&);
+
+ allocator_type get_allocator() const;
+
+ bool empty() const;
+ size_type size() const;
+ size_type max_size() const;
+
+ iterator begin();
+ iterator end();
+ const_iterator begin() const;
+ const_iterator end() const;
+
+ iterator insert(const value_type& obj);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+
+ void erase(const_iterator position);
+ size_type erase(const key_type& k);
+ void erase(const_iterator first, const_iterator last);
+ void clear();
+
+ void swap(hash_multiset&);
+
+ hasher hash_funct() const;
+ key_equal key_eq() const;
+
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ size_type count(const key_type& k) const;
+ pair<iterator, iterator> equal_range(const key_type& k);
+ pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
+
+ size_type bucket_count() const;
+ size_type max_bucket_count() const;
+
+ size_type elems_in_bucket(size_type n) const;
+
+ void resize(size_type n);
+};
+
+template <class Value, class Hash, class Pred, class Alloc>
+ void swap(hash_multiset<Value, Hash, Pred, Alloc>& x,
+ hash_multiset<Value, Hash, Pred, Alloc>& y);
+
+template <class Value, class Hash, class Pred, class Alloc>
+ bool
+ operator==(const hash_multiset<Value, Hash, Pred, Alloc>& x,
+ const hash_multiset<Value, Hash, Pred, Alloc>& y);
+
+template <class Value, class Hash, class Pred, class Alloc>
+ bool
+ operator!=(const hash_multiset<Value, Hash, Pred, Alloc>& x,
+ const hash_multiset<Value, Hash, Pred, Alloc>& y);
+} // __gnu_cxx
+
+*/
+
+#include <__config>
+#include <__hash_table>
+#include <algorithm>
+#include <ext/__hash>
+#include <functional>
+
+#if defined(__DEPRECATED) && __DEPRECATED
+# if defined(_LIBCPP_WARNING)
+_LIBCPP_WARNING("Use of the header <ext/hash_set> is deprecated. Migrate to <unordered_set>")
+# else
+# warning Use of the header <ext/hash_set> is deprecated. Migrate to <unordered_set>
+# endif
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+namespace __gnu_cxx {
+
+template <class _Value,
+ class _Hash = hash<_Value>,
+ class _Pred = std::equal_to<_Value>,
+ class _Alloc = std::allocator<_Value> >
+class _LIBCPP_TEMPLATE_VIS hash_set {
+public:
+ // types
+ typedef _Value key_type;
+ typedef key_type value_type;
+ typedef _Hash hasher;
+ typedef _Pred key_equal;
+ typedef _Alloc allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+
+private:
+ typedef std::__hash_table<value_type, hasher, key_equal, allocator_type> __table;
+
+ __table __table_;
+
+public:
+ typedef typename __table::pointer pointer;
+ typedef typename __table::const_pointer const_pointer;
+ typedef typename __table::size_type size_type;
+ typedef typename __table::difference_type difference_type;
+
+ typedef typename __table::const_iterator iterator;
+ typedef typename __table::const_iterator const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI hash_set() {}
+ _LIBCPP_HIDE_FROM_ABI explicit hash_set(
+ size_type __n, const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI hash_set(size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI hash_set(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ hash_set(_InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ hash_set(_InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI hash_set(const hash_set& __u);
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const { return allocator_type(__table_.__node_alloc()); }
+
+ _LIBCPP_HIDE_FROM_ABI bool empty() const { return __table_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const { return __table_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const { return __table_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const { return __table_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI std::pair<iterator, bool> insert(const value_type& __x) {
+ return __table_.__insert_unique(__x);
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, const value_type& __x) { return insert(__x).first; }
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last);
+
+ _LIBCPP_HIDE_FROM_ABI void erase(const_iterator __p) { __table_.erase(__p); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __table_.__erase_unique(__k); }
+ _LIBCPP_HIDE_FROM_ABI void erase(const_iterator __first, const_iterator __last) { __table_.erase(__first, __last); }
+ _LIBCPP_HIDE_FROM_ABI void clear() { __table_.clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(hash_set& __u) { __table_.swap(__u.__table_); }
+
+ _LIBCPP_HIDE_FROM_ABI hasher hash_funct() const { return __table_.hash_function(); }
+ _LIBCPP_HIDE_FROM_ABI key_equal key_eq() const { return __table_.key_eq(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __table_.__count_unique(__k); }
+ _LIBCPP_HIDE_FROM_ABI std::pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __table_.__equal_range_unique(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI std::pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __table_.__equal_range_unique(__k);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const { return __table_.bucket_count(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const { return __table_.max_bucket_count(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type elems_in_bucket(size_type __n) const { return __table_.bucket_size(__n); }
+
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n) { __table_.__rehash_unique(__n); }
+};
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(
+ size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_unique(__n);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(_InputIterator __first, _InputIterator __last) {
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_unique(__n);
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(const hash_set& __u) : __table_(__u.__table_) {
+ __table_.__rehash_unique(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+inline void hash_set<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first, _InputIterator __last) {
+ for (; __first != __last; ++__first)
+ __table_.__insert_unique(*__first);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(hash_set<_Value, _Hash, _Pred, _Alloc>& __x, hash_set<_Value, _Hash, _Pred, _Alloc>& __y) {
+ __x.swap(__y);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool
+operator==(const hash_set<_Value, _Hash, _Pred, _Alloc>& __x, const hash_set<_Value, _Hash, _Pred, _Alloc>& __y) {
+ if (__x.size() != __y.size())
+ return false;
+ typedef typename hash_set<_Value, _Hash, _Pred, _Alloc>::const_iterator const_iterator;
+ for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end(); __i != __ex; ++__i) {
+ const_iterator __j = __y.find(*__i);
+ if (__j == __ey || !(*__i == *__j))
+ return false;
+ }
+ return true;
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const hash_set<_Value, _Hash, _Pred, _Alloc>& __x, const hash_set<_Value, _Hash, _Pred, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Value,
+ class _Hash = hash<_Value>,
+ class _Pred = std::equal_to<_Value>,
+ class _Alloc = std::allocator<_Value> >
+class _LIBCPP_TEMPLATE_VIS hash_multiset {
+public:
+ // types
+ typedef _Value key_type;
+ typedef key_type value_type;
+ typedef _Hash hasher;
+ typedef _Pred key_equal;
+ typedef _Alloc allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+
+private:
+ typedef std::__hash_table<value_type, hasher, key_equal, allocator_type> __table;
+
+ __table __table_;
+
+public:
+ typedef typename __table::pointer pointer;
+ typedef typename __table::const_pointer const_pointer;
+ typedef typename __table::size_type size_type;
+ typedef typename __table::difference_type difference_type;
+
+ typedef typename __table::const_iterator iterator;
+ typedef typename __table::const_iterator const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI hash_multiset() {}
+ explicit _LIBCPP_HIDE_FROM_ABI
+ hash_multiset(size_type __n, const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI
+ hash_multiset(size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI hash_multiset(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ hash_multiset(_InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI hash_multiset(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI hash_multiset(const hash_multiset& __u);
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const { return allocator_type(__table_.__node_alloc()); }
+
+ _LIBCPP_HIDE_FROM_ABI bool empty() const { return __table_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const { return __table_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const { return __table_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const { return __table_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const value_type& __x) { return __table_.__insert_multi(__x); }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, const value_type& __x) { return insert(__x); }
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last);
+
+ _LIBCPP_HIDE_FROM_ABI void erase(const_iterator __p) { __table_.erase(__p); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __table_.__erase_multi(__k); }
+ _LIBCPP_HIDE_FROM_ABI void erase(const_iterator __first, const_iterator __last) { __table_.erase(__first, __last); }
+ _LIBCPP_HIDE_FROM_ABI void clear() { __table_.clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(hash_multiset& __u) { __table_.swap(__u.__table_); }
+
+ _LIBCPP_HIDE_FROM_ABI hasher hash_funct() const { return __table_.hash_function(); }
+ _LIBCPP_HIDE_FROM_ABI key_equal key_eq() const { return __table_.key_eq(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __table_.__count_multi(__k); }
+ _LIBCPP_HIDE_FROM_ABI std::pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __table_.__equal_range_multi(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI std::pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __table_.__equal_range_multi(__k);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const { return __table_.bucket_count(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const { return __table_.max_bucket_count(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type elems_in_bucket(size_type __n) const { return __table_.bucket_size(__n); }
+
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n) { __table_.__rehash_multi(__n); }
+};
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
+ size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_multi(__n);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(_InputIterator __first, _InputIterator __last) {
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_multi(__n);
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(const hash_multiset& __u) : __table_(__u.__table_) {
+ __table_.__rehash_multi(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+inline void hash_multiset<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first, _InputIterator __last) {
+ for (; __first != __last; ++__first)
+ __table_.__insert_multi(*__first);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(hash_multiset<_Value, _Hash, _Pred, _Alloc>& __x, hash_multiset<_Value, _Hash, _Pred, _Alloc>& __y) {
+ __x.swap(__y);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const hash_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
+ const hash_multiset<_Value, _Hash, _Pred, _Alloc>& __y) {
+ if (__x.size() != __y.size())
+ return false;
+ typedef typename hash_multiset<_Value, _Hash, _Pred, _Alloc>::const_iterator const_iterator;
+ typedef std::pair<const_iterator, const_iterator> _EqRng;
+ for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;) {
+ _EqRng __xeq = __x.equal_range(*__i);
+ _EqRng __yeq = __y.equal_range(*__i);
+ if (std::distance(__xeq.first, __xeq.second) != std::distance(__yeq.first, __yeq.second) ||
+ !std::is_permutation(__xeq.first, __xeq.second, __yeq.first))
+ return false;
+ __i = __xeq.second;
+ }
+ return true;
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const hash_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
+ const hash_multiset<_Value, _Hash, _Pred, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+} // namespace __gnu_cxx
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <iterator>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_HASH_SET
diff --git a/libcxx/include/__cxx03/fenv.h b/libcxx/include/__cxx03/fenv.h
new file mode 100644
index 00000000000000..5647f2b339555d
--- /dev/null
+++ b/libcxx/include/__cxx03/fenv.h
@@ -0,0 +1,114 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_FENV_H
+#define _LIBCPP_FENV_H
+
+/*
+ fenv.h synopsis
+
+This entire header is C99 / C++0X
+
+Macros:
+
+ FE_DIVBYZERO
+ FE_INEXACT
+ FE_INVALID
+ FE_OVERFLOW
+ FE_UNDERFLOW
+ FE_ALL_EXCEPT
+ FE_DOWNWARD
+ FE_TONEAREST
+ FE_TOWARDZERO
+ FE_UPWARD
+ FE_DFL_ENV
+
+Types:
+
+ fenv_t
+ fexcept_t
+
+int feclearexcept(int excepts);
+int fegetexceptflag(fexcept_t* flagp, int excepts);
+int feraiseexcept(int excepts);
+int fesetexceptflag(const fexcept_t* flagp, int excepts);
+int fetestexcept(int excepts);
+int fegetround();
+int fesetround(int round);
+int fegetenv(fenv_t* envp);
+int feholdexcept(fenv_t* envp);
+int fesetenv(const fenv_t* envp);
+int feupdateenv(const fenv_t* envp);
+
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if __has_include_next(<fenv.h>)
+# include_next <fenv.h>
+#endif
+
+#ifdef __cplusplus
+
+extern "C++" {
+
+# ifdef feclearexcept
+# undef feclearexcept
+# endif
+
+# ifdef fegetexceptflag
+# undef fegetexceptflag
+# endif
+
+# ifdef feraiseexcept
+# undef feraiseexcept
+# endif
+
+# ifdef fesetexceptflag
+# undef fesetexceptflag
+# endif
+
+# ifdef fetestexcept
+# undef fetestexcept
+# endif
+
+# ifdef fegetround
+# undef fegetround
+# endif
+
+# ifdef fesetround
+# undef fesetround
+# endif
+
+# ifdef fegetenv
+# undef fegetenv
+# endif
+
+# ifdef feholdexcept
+# undef feholdexcept
+# endif
+
+# ifdef fesetenv
+# undef fesetenv
+# endif
+
+# ifdef feupdateenv
+# undef feupdateenv
+# endif
+
+} // extern "C++"
+
+#endif // defined(__cplusplus)
+
+#endif // _LIBCPP_FENV_H
diff --git a/libcxx/include/__cxx03/filesystem b/libcxx/include/__cxx03/filesystem
new file mode 100644
index 00000000000000..6ea04df0a089b0
--- /dev/null
+++ b/libcxx/include/__cxx03/filesystem
@@ -0,0 +1,577 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_FILESYSTEM
+#define _LIBCPP_FILESYSTEM
+
+/*
+ filesystem synopsis
+
+ namespace std::filesystem {
+
+ // `class path` from http://eel.is/c++draft/fs.class.path.general#6
+ class path {
+ public:
+ using value_type = see below;
+ using string_type = basic_string<value_type>;
+ static constexpr value_type preferred_separator = see below;
+
+ enum format;
+
+ path() noexcept;
+ path(const path& p);
+ path(path&& p) noexcept;
+ path(string_type&& source, format fmt = auto_format);
+ template<class Source>
+ path(const Source& source, format fmt = auto_format);
+ template<class InputIterator>
+ path(InputIterator first, InputIterator last, format fmt = auto_format);
+ template<class Source>
+ path(const Source& source, const locale& loc, format fmt = auto_format);
+ template<class InputIterator>
+ path(InputIterator first, InputIterator last, const locale& loc, format fmt = auto_format);
+ ~path();
+
+ path& operator=(const path& p);
+ path& operator=(path&& p) noexcept;
+ path& operator=(string_type&& source);
+ path& assign(string_type&& source);
+ template<class Source>
+ path& operator=(const Source& source);
+ template<class Source>
+ path& assign(const Source& source);
+ template<class InputIterator>
+ path& assign(InputIterator first, InputIterator last);
+
+ path& operator/=(const path& p);
+ template<class Source>
+ path& operator/=(const Source& source);
+ template<class Source>
+ path& append(const Source& source);
+ template<class InputIterator>
+ path& append(InputIterator first, InputIterator last);
+
+ path& operator+=(const path& x);
+ path& operator+=(const string_type& x);
+ path& operator+=(basic_string_view<value_type> x);
+ path& operator+=(const value_type* x);
+ path& operator+=(value_type x);
+ template<class Source>
+ path& operator+=(const Source& x);
+ template<class EcharT>
+ path& operator+=(EcharT x);
+ template<class Source>
+ path& concat(const Source& x);
+ template<class InputIterator>
+ path& concat(InputIterator first, InputIterator last);
+
+ void clear() noexcept;
+ path& make_preferred();
+ path& remove_filename();
+ path& replace_filename(const path& replacement);
+ path& replace_extension(const path& replacement = path());
+ void swap(path& rhs) noexcept;
+
+ friend bool operator==(const path& lhs, const path& rhs) noexcept;
+ friend bool operator!=(const path& lhs, const path& rhs) noexcept; // removed in C++20
+ friend bool operator< (const path& lhs, const path& rhs) noexcept; // removed in C++20
+ friend bool operator<=(const path& lhs, const path& rhs) noexcept; // removed in C++20
+ friend bool operator> (const path& lhs, const path& rhs) noexcept; // removed in C++20
+ friend bool operator>=(const path& lhs, const path& rhs) noexcept; // removed in C++20
+ friend strong_ordering operator<=>(const path& lhs, const path& rhs) noexcept; // C++20
+
+ friend path operator/(const path& lhs, const path& rhs);
+
+ const string_type& native() const noexcept;
+ const value_type* c_str() const noexcept;
+ operator string_type() const;
+
+ template<class EcharT, class traits = char_traits<EcharT>,
+ class Allocator = allocator<EcharT>>
+ basic_string<EcharT, traits, Allocator>
+ string(const Allocator& a = Allocator()) const;
+ std::string string() const;
+ std::wstring wstring() const;
+ std::u8string u8string() const;
+ std::u16string u16string() const;
+ std::u32string u32string() const;
+
+ template<class EcharT, class traits = char_traits<EcharT>,
+ class Allocator = allocator<EcharT>>
+ basic_string<EcharT, traits, Allocator>
+ generic_string(const Allocator& a = Allocator()) const;
+ std::string generic_string() const;
+ std::wstring generic_wstring() const;
+ std::u8string generic_u8string() const;
+ std::u16string generic_u16string() const;
+ std::u32string generic_u32string() const;
+
+ int compare(const path& p) const noexcept;
+ int compare(const string_type& s) const;
+ int compare(basic_string_view<value_type> s) const;
+ int compare(const value_type* s) const;
+
+ path root_name() const;
+ path root_directory() const;
+ path root_path() const;
+ path relative_path() const;
+ path parent_path() const;
+ path filename() const;
+ path stem() const;
+ path extension() const;
+
+ [[nodiscard]] bool empty() const noexcept;
+ bool has_root_name() const;
+ bool has_root_directory() const;
+ bool has_root_path() const;
+ bool has_relative_path() const;
+ bool has_parent_path() const;
+ bool has_filename() const;
+ bool has_stem() const;
+ bool has_extension() const;
+ bool is_absolute() const;
+ bool is_relative() const;
+
+ path lexically_normal() const;
+ path lexically_relative(const path& base) const;
+ path lexically_proximate(const path& base) const;
+
+ class iterator;
+ using const_iterator = iterator;
+
+ iterator begin() const;
+ iterator end() const;
+
+ template<class charT, class traits>
+ friend basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const path& p);
+ template<class charT, class traits>
+ friend basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is, path& p);
+ };
+
+ void swap(path& lhs, path& rhs) noexcept;
+ size_t hash_value(const path& p) noexcept;
+
+ // [fs.path.hash], hash support
+ template<> struct hash<filesystem::path>;
+
+ template <class Source>
+ path u8path(const Source& source);
+ template <class InputIterator>
+ path u8path(InputIterator first, InputIterator last);
+
+ class filesystem_error;
+
+ class directory_entry {
+ public:
+ directory_entry() noexcept = default;
+ directory_entry(const directory_entry&) = default;
+ directory_entry(directory_entry&&) noexcept = default;
+ explicit directory_entry(const filesystem::path& p);
+ directory_entry(const filesystem::path& p, error_code& ec);
+ ~directory_entry();
+
+ directory_entry& operator=(const directory_entry&) = default;
+ directory_entry& operator=(directory_entry&&) noexcept = default;
+
+ void assign(const filesystem::path& p);
+ void assign(const filesystem::path& p, error_code& ec);
+ void replace_filename(const filesystem::path& p);
+ void replace_filename(const filesystem::path& p, error_code& ec);
+ void refresh();
+ void refresh(error_code& ec) noexcept;
+
+ const filesystem::path& path() const noexcept;
+ operator const filesystem::path&() const noexcept;
+ bool exists() const;
+ bool exists(error_code& ec) const noexcept;
+ bool is_block_file() const;
+ bool is_block_file(error_code& ec) const noexcept;
+ bool is_character_file() const;
+ bool is_character_file(error_code& ec) const noexcept;
+ bool is_directory() const;
+ bool is_directory(error_code& ec) const noexcept;
+ bool is_fifo() const;
+ bool is_fifo(error_code& ec) const noexcept;
+ bool is_other() const;
+ bool is_other(error_code& ec) const noexcept;
+ bool is_regular_file() const;
+ bool is_regular_file(error_code& ec) const noexcept;
+ bool is_socket() const;
+ bool is_socket(error_code& ec) const noexcept;
+ bool is_symlink() const;
+ bool is_symlink(error_code& ec) const noexcept;
+ uintmax_t file_size() const;
+ uintmax_t file_size(error_code& ec) const noexcept;
+ uintmax_t hard_link_count() const;
+ uintmax_t hard_link_count(error_code& ec) const noexcept;
+ file_time_type last_write_time() const;
+ file_time_type last_write_time(error_code& ec) const noexcept;
+ file_status status() const;
+ file_status status(error_code& ec) const noexcept;
+ file_status symlink_status() const;
+ file_status symlink_status(error_code& ec) const noexcept;
+
+ bool operator==(const directory_entry& rhs) const noexcept;
+ bool operator!=(const directory_entry& rhs) const noexcept; // removed in C++20
+ bool operator< (const directory_entry& rhs) const noexcept; // removed in C++20
+ bool operator<=(const directory_entry& rhs) const noexcept; // removed in C++20
+ bool operator> (const directory_entry& rhs) const noexcept; // removed in C++20
+ bool operator>=(const directory_entry& rhs) const noexcept; // removed in C++20
+ strong_ordering operator<=>(const directory_entry& rhs) const noexcept; // since C++20
+
+ template<class charT, class traits>
+ friend basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os, const directory_entry& d);
+
+ private:
+ filesystem::path pathobject; // exposition only
+ friend class directory_iterator; // exposition only
+ };
+
+ class directory_iterator {
+ public:
+ using iterator_category = input_iterator_tag;
+ using value_type = directory_entry;
+ using difference_type = ptrdiff_t;
+ using pointer = const directory_entry*;
+ using reference = const directory_entry&;
+
+ // [fs.dir.itr.members], member functions
+ directory_iterator() noexcept;
+ explicit directory_iterator(const path& p);
+ directory_iterator(const path& p, directory_options options);
+ directory_iterator(const path& p, error_code& ec);
+ directory_iterator(const path& p, directory_options options,
+ error_code& ec);
+ directory_iterator(const directory_iterator& rhs);
+ directory_iterator(directory_iterator&& rhs) noexcept;
+ ~directory_iterator();
+
+ directory_iterator& operator=(const directory_iterator& rhs);
+ directory_iterator& operator=(directory_iterator&& rhs) noexcept;
+
+ const directory_entry& operator*() const;
+ const directory_entry* operator->() const;
+ directory_iterator& operator++();
+ directory_iterator& increment(error_code& ec);
+
+ bool operator==(default_sentinel_t) const noexcept { // since C++20
+ return *this == directory_iterator();
+ }
+
+ // other members as required by [input.iterators], input iterators
+ };
+
+ // enable directory_iterator range-based for statements
+ directory_iterator begin(directory_iterator iter) noexcept;
+ directory_iterator end(directory_iterator) noexcept;
+
+class recursive_directory_iterator {
+ public:
+ using iterator_category = input_iterator_tag;
+ using value_type = directory_entry;
+ using difference_type = ptrdiff_t;
+ using pointer = const directory_entry*;
+ using reference = const directory_entry&;
+
+ // [fs.rec.dir.itr.members], constructors and destructor
+ recursive_directory_iterator() noexcept;
+ explicit recursive_directory_iterator(const path& p);
+ recursive_directory_iterator(const path& p, directory_options options);
+ recursive_directory_iterator(const path& p, directory_options options,
+ error_code& ec);
+ recursive_directory_iterator(const path& p, error_code& ec);
+ recursive_directory_iterator(const recursive_directory_iterator& rhs);
+ recursive_directory_iterator(recursive_directory_iterator&& rhs) noexcept;
+ ~recursive_directory_iterator();
+
+ // [fs.rec.dir.itr.members], observers
+ directory_options options() const;
+ int depth() const;
+ bool recursion_pending() const;
+
+ const directory_entry& operator*() const;
+ const directory_entry* operator->() const;
+
+ // [fs.rec.dir.itr.members], modifiers
+ recursive_directory_iterator&
+ operator=(const recursive_directory_iterator& rhs);
+ recursive_directory_iterator&
+ operator=(recursive_directory_iterator&& rhs) noexcept;
+
+ recursive_directory_iterator& operator++();
+ recursive_directory_iterator& increment(error_code& ec);
+
+ void pop();
+ void pop(error_code& ec);
+ void disable_recursion_pending();
+
+ bool operator==(default_sentinel_t) const noexcept { // since C++20
+ return *this == recursive_directory_iterator();
+ }
+
+ // other members as required by [input.iterators], input iterators
+ };
+
+ // enable recursive_directory_iterator range-based for statements
+ recursive_directory_iterator begin(recursive_directory_iterator iter) noexcept;
+ recursive_directory_iterator end(recursive_directory_iterator) noexcept;
+
+ class file_status {
+ public:
+ // [fs.file.status.cons], constructors and destructor
+ file_status() noexcept : file_status(file_type::none) {}
+ explicit file_status(file_type ft,
+ perms prms = perms::unknown) noexcept;
+ file_status(const file_status&) noexcept = default;
+ file_status(file_status&&) noexcept = default;
+ ~file_status();
+
+ // assignments
+ file_status& operator=(const file_status&) noexcept = default;
+ file_status& operator=(file_status&&) noexcept = default;
+
+ // [fs.file.status.mods], modifiers
+ void type(file_type ft) noexcept;
+ void permissions(perms prms) noexcept;
+
+ // [fs.file.status.obs], observers
+ file_type type() const noexcept;
+ perms permissions() const noexcept;
+
+ friend bool operator==(const file_status& lhs, const file_status& rhs) noexcept
+ { return lhs.type() == rhs.type() && lhs.permissions() == rhs.permissions(); } // C++20
+ };
+
+ struct space_info
+ {
+ uintmax_t capacity;
+ uintmax_t free;
+ uintmax_t available;
+
+ friend bool operator==(const space_info&, const space_info&) = default; // C++20
+ };
+
+ enum class file_type;
+ enum class perms;
+ enum class perm_options;
+ enum class copy_options;
+ enum class directory_options;
+
+ typedef chrono::time_point<trivial-clock> file_time_type;
+
+ // operational functions
+
+ path absolute(const path& p);
+ path absolute(const path& p, error_code &ec);
+
+ path canonical(const path& p);
+ path canonical(const path& p, error_code& ec);
+
+ void copy(const path& from, const path& to);
+ void copy(const path& from, const path& to, error_code& ec);
+ void copy(const path& from, const path& to, copy_options options);
+ void copy(const path& from, const path& to, copy_options options,
+ error_code& ec);
+
+ bool copy_file(const path& from, const path& to);
+ bool copy_file(const path& from, const path& to, error_code& ec);
+ bool copy_file(const path& from, const path& to, copy_options option);
+ bool copy_file(const path& from, const path& to, copy_options option,
+ error_code& ec);
+
+ void copy_symlink(const path& existing_symlink, const path& new_symlink);
+ void copy_symlink(const path& existing_symlink, const path& new_symlink,
+ error_code& ec) noexcept;
+
+ bool create_directories(const path& p);
+ bool create_directories(const path& p, error_code& ec);
+
+ bool create_directory(const path& p);
+ bool create_directory(const path& p, error_code& ec) noexcept;
+
+ bool create_directory(const path& p, const path& attributes);
+ bool create_directory(const path& p, const path& attributes,
+ error_code& ec) noexcept;
+
+ void create_directory_symlink(const path& to, const path& new_symlink);
+ void create_directory_symlink(const path& to, const path& new_symlink,
+ error_code& ec) noexcept;
+
+ void create_hard_link(const path& to, const path& new_hard_link);
+ void create_hard_link(const path& to, const path& new_hard_link,
+ error_code& ec) noexcept;
+
+ void create_symlink(const path& to, const path& new_symlink);
+ void create_symlink(const path& to, const path& new_symlink,
+ error_code& ec) noexcept;
+
+ path current_path();
+ path current_path(error_code& ec);
+ void current_path(const path& p);
+ void current_path(const path& p, error_code& ec) noexcept;
+
+ bool exists(file_status s) noexcept;
+ bool exists(const path& p);
+ bool exists(const path& p, error_code& ec) noexcept;
+
+ bool equivalent(const path& p1, const path& p2);
+ bool equivalent(const path& p1, const path& p2, error_code& ec) noexcept;
+
+ uintmax_t file_size(const path& p);
+ uintmax_t file_size(const path& p, error_code& ec) noexcept;
+
+ uintmax_t hard_link_count(const path& p);
+ uintmax_t hard_link_count(const path& p, error_code& ec) noexcept;
+
+ bool is_block_file(file_status s) noexcept;
+ bool is_block_file(const path& p);
+ bool is_block_file(const path& p, error_code& ec) noexcept;
+
+ bool is_character_file(file_status s) noexcept;
+ bool is_character_file(const path& p);
+ bool is_character_file(const path& p, error_code& ec) noexcept;
+
+ bool is_directory(file_status s) noexcept;
+ bool is_directory(const path& p);
+ bool is_directory(const path& p, error_code& ec) noexcept;
+
+ bool is_empty(const path& p);
+ bool is_empty(const path& p, error_code& ec) noexcept;
+
+ bool is_fifo(file_status s) noexcept;
+ bool is_fifo(const path& p);
+ bool is_fifo(const path& p, error_code& ec) noexcept;
+
+ bool is_other(file_status s) noexcept;
+ bool is_other(const path& p);
+ bool is_other(const path& p, error_code& ec) noexcept;
+
+ bool is_regular_file(file_status s) noexcept;
+ bool is_regular_file(const path& p);
+ bool is_regular_file(const path& p, error_code& ec) noexcept;
+
+ bool is_socket(file_status s) noexcept;
+ bool is_socket(const path& p);
+ bool is_socket(const path& p, error_code& ec) noexcept;
+
+ bool is_symlink(file_status s) noexcept;
+ bool is_symlink(const path& p);
+ bool is_symlink(const path& p, error_code& ec) noexcept;
+
+ file_time_type last_write_time(const path& p);
+ file_time_type last_write_time(const path& p, error_code& ec) noexcept;
+ void last_write_time(const path& p, file_time_type new_time);
+ void last_write_time(const path& p, file_time_type new_time,
+ error_code& ec) noexcept;
+
+ void permissions(const path& p, perms prms,
+ perm_options opts=perm_options::replace);
+ void permissions(const path& p, perms prms, error_code& ec) noexcept;
+ void permissions(const path& p, perms prms, perm_options opts,
+ error_code& ec);
+
+ path proximate(const path& p, error_code& ec);
+ path proximate(const path& p, const path& base = current_path());
+ path proximate(const path& p, const path& base, error_code &ec);
+
+ path read_symlink(const path& p);
+ path read_symlink(const path& p, error_code& ec);
+
+ path relative(const path& p, error_code& ec);
+ path relative(const path& p, const path& base=current_path());
+ path relative(const path& p, const path& base, error_code& ec);
+
+ bool remove(const path& p);
+ bool remove(const path& p, error_code& ec) noexcept;
+
+ uintmax_t remove_all(const path& p);
+ uintmax_t remove_all(const path& p, error_code& ec);
+
+ void rename(const path& from, const path& to);
+ void rename(const path& from, const path& to, error_code& ec) noexcept;
+
+ void resize_file(const path& p, uintmax_t size);
+ void resize_file(const path& p, uintmax_t size, error_code& ec) noexcept;
+
+ space_info space(const path& p);
+ space_info space(const path& p, error_code& ec) noexcept;
+
+ file_status status(const path& p);
+ file_status status(const path& p, error_code& ec) noexcept;
+
+ bool status_known(file_status s) noexcept;
+
+ file_status symlink_status(const path& p);
+ file_status symlink_status(const path& p, error_code& ec) noexcept;
+
+ path temp_directory_path();
+ path temp_directory_path(error_code& ec);
+
+ path weakly_canonical(path const& p);
+ path weakly_canonical(path const& p, error_code& ec);
+
+} // namespace std::filesystem
+
+template <>
+inline constexpr bool std::ranges::enable_borrowed_range<std::filesystem::directory_iterator> = true;
+template <>
+inline constexpr bool std::ranges::enable_borrowed_range<std::filesystem::recursive_directory_iterator> = true;
+
+template <>
+inline constexpr bool std::ranges::enable_view<std::filesystem::directory_iterator> = true;
+template <>
+inline constexpr bool std::ranges::enable_view<std::filesystem::recursive_directory_iterator> = true;
+
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 17
+# include <__filesystem/copy_options.h>
+# include <__filesystem/directory_entry.h>
+# include <__filesystem/directory_iterator.h>
+# include <__filesystem/directory_options.h>
+# include <__filesystem/file_status.h>
+# include <__filesystem/file_time_type.h>
+# include <__filesystem/file_type.h>
+# include <__filesystem/filesystem_error.h>
+# include <__filesystem/operations.h>
+# include <__filesystem/path.h>
+# include <__filesystem/path_iterator.h>
+# include <__filesystem/perm_options.h>
+# include <__filesystem/perms.h>
+# include <__filesystem/recursive_directory_iterator.h>
+# include <__filesystem/space_info.h>
+# include <__filesystem/u8path.h>
+#endif
+
+#include <version>
+
+// standard-mandated includes
+
+// [fs.filesystem.syn]
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <cstdlib>
+# include <cstring>
+# include <iosfwd>
+# include <new>
+# include <system_error>
+#endif
+
+#endif // _LIBCPP_FILESYSTEM
diff --git a/libcxx/include/__cxx03/float.h b/libcxx/include/__cxx03/float.h
new file mode 100644
index 00000000000000..d572866c1358be
--- /dev/null
+++ b/libcxx/include/__cxx03/float.h
@@ -0,0 +1,95 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_FLOAT_H
+#define _LIBCPP_FLOAT_H
+
+/*
+ float.h synopsis
+
+Macros:
+
+ FLT_ROUNDS
+ FLT_EVAL_METHOD // C99
+ FLT_RADIX
+
+ FLT_MANT_DIG
+ DBL_MANT_DIG
+ LDBL_MANT_DIG
+
+ FLT_HAS_SUBNORM // C11
+ DBL_HAS_SUBNORM // C11
+ LDBL_HAS_SUBNORM // C11
+
+ DECIMAL_DIG // C99
+ FLT_DECIMAL_DIG // C11
+ DBL_DECIMAL_DIG // C11
+ LDBL_DECIMAL_DIG // C11
+
+ FLT_DIG
+ DBL_DIG
+ LDBL_DIG
+
+ FLT_MIN_EXP
+ DBL_MIN_EXP
+ LDBL_MIN_EXP
+
+ FLT_MIN_10_EXP
+ DBL_MIN_10_EXP
+ LDBL_MIN_10_EXP
+
+ FLT_MAX_EXP
+ DBL_MAX_EXP
+ LDBL_MAX_EXP
+
+ FLT_MAX_10_EXP
+ DBL_MAX_10_EXP
+ LDBL_MAX_10_EXP
+
+ FLT_MAX
+ DBL_MAX
+ LDBL_MAX
+
+ FLT_EPSILON
+ DBL_EPSILON
+ LDBL_EPSILON
+
+ FLT_MIN
+ DBL_MIN
+ LDBL_MIN
+
+ FLT_TRUE_MIN // C11
+ DBL_TRUE_MIN // C11
+ LDBL_TRUE_MIN // C11
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if __has_include_next(<float.h>)
+# include_next <float.h>
+#endif
+
+#ifdef __cplusplus
+
+# ifndef FLT_EVAL_METHOD
+# define FLT_EVAL_METHOD __FLT_EVAL_METHOD__
+# endif
+
+# ifndef DECIMAL_DIG
+# define DECIMAL_DIG __DECIMAL_DIG__
+# endif
+
+#endif // __cplusplus
+
+#endif // _LIBCPP_FLOAT_H
diff --git a/libcxx/include/__cxx03/format b/libcxx/include/__cxx03/format
new file mode 100644
index 00000000000000..a88b3ef8528e2d
--- /dev/null
+++ b/libcxx/include/__cxx03/format
@@ -0,0 +1,257 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_FORMAT
+#define _LIBCPP_FORMAT
+
+/*
+
+namespace std {
+ // [format.context], class template basic_format_context
+ template<class Out, class charT> class basic_format_context;
+ using format_context = basic_format_context<unspecified, char>;
+ using wformat_context = basic_format_context<unspecified, wchar_t>;
+
+ // [format.args], class template basic_format_args
+ template<class Context> class basic_format_args;
+ using format_args = basic_format_args<format_context>;
+ using wformat_args = basic_format_args<wformat_context>;
+
+ // [format.fmt.string], class template basic_format_string
+ template<class charT, class... Args>
+ struct basic_format_string { // since C++23, exposition only before C++23
+ private:
+ basic_string_view<charT> str; // exposition only
+
+ public:
+ template<class T> consteval basic_format_string(const T& s);
+ basic_format_string(runtime-format-string<charT> s) noexcept : str(s.str) {} // since C++26
+
+ constexpr basic_string_view<charT> get() const noexcept { return str; }
+ };
+ template<class... Args>
+ using format_string = // since C++23, exposition only before C++23
+ basic_format_string<char, type_identity_t<Args>...>;
+ template<class... Args>
+ using wformat_string = // since C++23, exposition only before C++23
+ basic_format_string<wchar_t, type_identity_t<Args>...>;
+
+ template<class charT> struct runtime-format-string { // since C++26, exposition-only
+ private:
+ basic_string_view<charT> str; // exposition-only
+
+ public:
+ runtime-format-string(basic_string_view<charT> s) noexcept : str(s) {}
+
+ runtime-format-string(const runtime-format-string&) = delete;
+ runtime-format-string& operator=(const runtime-format-string&) = delete;
+ };
+
+ runtime-format-string<char> runtime_format(string_view fmt) noexcept {
+ return fmt;
+ }
+ runtime-format-string<wchar_t> runtime_format(wstring_view fmt) noexcept {
+ return fmt;
+ }
+
+ // [format.functions], formatting functions
+ template<class... Args>
+ string format(format-string<Args...> fmt, Args&&... args);
+ template<class... Args>
+ wstring format(wformat-string<Args...> fmt, Args&&... args);
+ template<class... Args>
+ string format(const locale& loc, format-string<Args...> fmt, Args&&... args);
+ template<class... Args>
+ wstring format(const locale& loc, wformat-string<Args...> fmt, Args&&... args);
+
+ string vformat(string_view fmt, format_args args);
+ wstring vformat(wstring_view fmt, wformat_args args);
+ string vformat(const locale& loc, string_view fmt, format_args args);
+ wstring vformat(const locale& loc, wstring_view fmt, wformat_args args);
+
+ template<class Out, class... Args>
+ Out format_to(Out out, format-string<Args...> fmt, Args&&... args);
+ template<class Out, class... Args>
+ Out format_to(Out out, wformat-string<Args...> fmt, Args&&... args);
+ template<class Out, class... Args>
+ Out format_to(Out out, const locale& loc, format-string<Args...> fmt, Args&&... args);
+ template<class Out, class... Args>
+ Out format_to(Out out, const locale& loc, wformat-string<Args...> fmt, Args&&... args);
+
+ template<class Out>
+ Out vformat_to(Out out, string_view fmt, format_args args);
+ template<class Out>
+ Out vformat_to(Out out, wstring_view fmt, wformat_args args);
+ template<class Out>
+ Out vformat_to(Out out, const locale& loc, string_view fmt,
+ format_args char> args);
+ template<class Out>
+ Out vformat_to(Out out, const locale& loc, wstring_view fmt,
+ wformat_args args);
+
+ template<class Out> struct format_to_n_result {
+ Out out;
+ iter_difference_t<Out> size;
+ };
+ template<class Out, class... Args>
+ format_to_n_result<Out> format_to_n(Out out, iter_difference_t<Out> n,
+ format-string<Args...> fmt, Args&&... args);
+ template<class Out, class... Args>
+ format_to_n_result<Out> format_to_n(Out out, iter_difference_t<Out> n,
+ wformat-string<Args...> fmt, Args&&... args);
+ template<class Out, class... Args>
+ format_to_n_result<Out> format_to_n(Out out, iter_difference_t<Out> n,
+ const locale& loc, format-string<Args...> fmt,
+ Args&&... args);
+ template<class Out, class... Args>
+ format_to_n_result<Out> format_to_n(Out out, iter_difference_t<Out> n,
+ const locale& loc, wformat-string<Args...> fmt,
+ Args&&... args);
+
+ template<class... Args>
+ size_t formatted_size(format-string<Args...> fmt, Args&&... args);
+ template<class... Args>
+ size_t formatted_size(wformat-string<Args...> fmt, Args&&... args);
+ template<class... Args>
+ size_t formatted_size(const locale& loc, format-string<Args...> fmt, Args&&... args);
+ template<class... Args>
+ size_t formatted_size(const locale& loc, wformat-string<Args...> fmt, Args&&... args);
+
+ // [format.formatter], formatter
+ template<class T, class charT = char> struct formatter;
+
+ // [format.parse.ctx], class template basic_format_parse_context
+ template<class charT> class basic_format_parse_context;
+ using format_parse_context = basic_format_parse_context<char>;
+ using wformat_parse_context = basic_format_parse_context<wchar_t>;
+
+ // [format.range], formatting of ranges
+ // [format.range.fmtkind], variable template format_kind
+ enum class range_format { // since C++23
+ disabled,
+ map,
+ set,
+ sequence,
+ string,
+ debug_string
+ };
+
+ template<class R>
+ constexpr unspecified format_kind = unspecified; // since C++23
+
+ template<ranges::input_range R>
+ requires same_as<R, remove_cvref_t<R>>
+ constexpr range_format format_kind<R> = see below; // since C++23
+
+ // [format.range.formatter], class template range_formatter
+ template<class T, class charT = char>
+ requires same_as<remove_cvref_t<T>, T> && formattable<T, charT>
+ class range_formatter; // since C++23
+
+ // [format.range.fmtdef], class template range-default-formatter
+ template<range_format K, ranges::input_range R, class charT>
+ struct range-default-formatter; // exposition only, since C++23
+
+ // [format.range.fmtmap], [format.range.fmtset], [format.range.fmtstr],
+ // specializations for maps, sets, and strings
+ template<ranges::input_range R, class charT>
+ requires (format_kind<R> != range_format::disabled) &&
+ formattable<ranges::range_reference_t<R>, charT>
+ struct formatter<R, charT> : range-default-formatter<format_kind<R>, R, charT> { }; // since C++23
+
+ // [format.arguments], arguments
+ // [format.arg], class template basic_format_arg
+ template<class Context> class basic_format_arg;
+
+ template<class Visitor, class Context>
+ see below visit_format_arg(Visitor&& vis, basic_format_arg<Context> arg); // Deprecated in C++26
+
+ // [format.arg.store], class template format-arg-store
+ template<class Context, class... Args> struct format-arg-store; // exposition only
+
+ template<class Context = format_context, class... Args>
+ format-arg-store<Context, Args...>
+ make_format_args(Args&... args);
+ template<class... Args>
+ format-arg-store<wformat_context, Args...>
+ make_wformat_args(Args&... args);
+
+ // [format.error], class format_error
+ class format_error;
+}
+
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 20
+# include <__format/buffer.h>
+# include <__format/concepts.h>
+# include <__format/container_adaptor.h>
+# include <__format/enable_insertable.h>
+# include <__format/escaped_output_table.h>
+# include <__format/extended_grapheme_cluster_table.h>
+# include <__format/format_arg.h>
+# include <__format/format_arg_store.h>
+# include <__format/format_args.h>
+# include <__format/format_context.h>
+# include <__format/format_error.h>
+# include <__format/format_functions.h>
+# include <__format/format_parse_context.h>
+# include <__format/format_string.h>
+# include <__format/format_to_n_result.h>
+# include <__format/formatter.h>
+# include <__format/formatter_bool.h>
+# include <__format/formatter_char.h>
+# include <__format/formatter_floating_point.h>
+# include <__format/formatter_integer.h>
+# include <__format/formatter_pointer.h>
+# include <__format/formatter_string.h>
+# include <__format/formatter_tuple.h>
+# include <__format/parser_std_format_spec.h>
+# include <__format/range_default_formatter.h>
+# include <__format/range_formatter.h>
+# include <__format/unicode.h>
+# include <__fwd/format.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <array>
+# include <cctype>
+# include <cerrno>
+# include <clocale>
+# include <cmath>
+# include <cstddef>
+# include <cstdint>
+# include <cstdlib>
+# include <cstring>
+# include <initializer_list>
+# include <limits>
+# include <locale>
+# include <new>
+# include <optional>
+# include <queue>
+# include <stack>
+# include <stdexcept>
+# include <string>
+# include <string_view>
+# include <tuple>
+
+# if !defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+# include <cwchar>
+# endif
+#endif
+
+#endif // _LIBCPP_FORMAT
diff --git a/libcxx/include/__cxx03/forward_list b/libcxx/include/__cxx03/forward_list
new file mode 100644
index 00000000000000..b14d2cb6c78036
--- /dev/null
+++ b/libcxx/include/__cxx03/forward_list
@@ -0,0 +1,1575 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_FORWARD_LIST
+#define _LIBCPP_FORWARD_LIST
+
+/*
+ forward_list synopsis
+
+namespace std
+{
+
+template <class T, class Allocator = allocator<T>>
+class forward_list
+{
+public:
+ typedef T value_type;
+ typedef Allocator allocator_type;
+
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef <details> iterator;
+ typedef <details> const_iterator;
+
+ forward_list()
+ noexcept(is_nothrow_default_constructible<allocator_type>::value);
+ explicit forward_list(const allocator_type& a);
+ explicit forward_list(size_type n);
+ explicit forward_list(size_type n, const allocator_type& a); // C++14
+ forward_list(size_type n, const value_type& v);
+ forward_list(size_type n, const value_type& v, const allocator_type& a);
+ template <class InputIterator>
+ forward_list(InputIterator first, InputIterator last);
+ template <class InputIterator>
+ forward_list(InputIterator first, InputIterator last, const allocator_type& a);
+ template<container-compatible-range<T> R>
+ forward_list(from_range_t, R&& rg, const Allocator& = Allocator()); // C++23
+ forward_list(const forward_list& x);
+ forward_list(const forward_list& x, const allocator_type& a);
+ forward_list(forward_list&& x)
+ noexcept(is_nothrow_move_constructible<allocator_type>::value);
+ forward_list(forward_list&& x, const allocator_type& a);
+ forward_list(initializer_list<value_type> il);
+ forward_list(initializer_list<value_type> il, const allocator_type& a);
+
+ ~forward_list();
+
+ forward_list& operator=(const forward_list& x);
+ forward_list& operator=(forward_list&& x)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value);
+ forward_list& operator=(initializer_list<value_type> il);
+
+ template <class InputIterator>
+ void assign(InputIterator first, InputIterator last);
+ template<container-compatible-range<T> R>
+ void assign_range(R&& rg); // C++23
+ void assign(size_type n, const value_type& v);
+ void assign(initializer_list<value_type> il);
+
+ allocator_type get_allocator() const noexcept;
+
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+
+ iterator before_begin() noexcept;
+ const_iterator before_begin() const noexcept;
+ const_iterator cbefore_begin() const noexcept;
+
+ bool empty() const noexcept;
+ size_type max_size() const noexcept;
+
+ reference front();
+ const_reference front() const;
+
+ template <class... Args> reference emplace_front(Args&&... args); // reference in C++17
+ void push_front(const value_type& v);
+ void push_front(value_type&& v);
+ template<container-compatible-range<T> R>
+ void prepend_range(R&& rg); // C++23
+
+ void pop_front();
+
+ template <class... Args>
+ iterator emplace_after(const_iterator p, Args&&... args);
+ iterator insert_after(const_iterator p, const value_type& v);
+ iterator insert_after(const_iterator p, value_type&& v);
+ iterator insert_after(const_iterator p, size_type n, const value_type& v);
+ template <class InputIterator>
+ iterator insert_after(const_iterator p,
+ InputIterator first, InputIterator last);
+ template<container-compatible-range<T> R>
+ iterator insert_range_after(const_iterator position, R&& rg); // C++23
+ iterator insert_after(const_iterator p, initializer_list<value_type> il);
+
+ iterator erase_after(const_iterator p);
+ iterator erase_after(const_iterator first, const_iterator last);
+
+ void swap(forward_list& x)
+ noexcept(allocator_traits<allocator_type>::is_always_equal::value); // C++17
+
+ void resize(size_type n);
+ void resize(size_type n, const value_type& v);
+ void clear() noexcept;
+
+ void splice_after(const_iterator p, forward_list& x);
+ void splice_after(const_iterator p, forward_list&& x);
+ void splice_after(const_iterator p, forward_list& x, const_iterator i);
+ void splice_after(const_iterator p, forward_list&& x, const_iterator i);
+ void splice_after(const_iterator p, forward_list& x,
+ const_iterator first, const_iterator last);
+ void splice_after(const_iterator p, forward_list&& x,
+ const_iterator first, const_iterator last);
+ size_type remove(const value_type& v); // void before C++20
+ template <class Predicate>
+ size_type remove_if(Predicate pred); // void before C++20
+ size_type unique(); // void before C++20
+ template <class BinaryPredicate>
+ size_type unique(BinaryPredicate binary_pred); // void before C++20
+ void merge(forward_list& x);
+ void merge(forward_list&& x);
+ template <class Compare> void merge(forward_list& x, Compare comp);
+ template <class Compare> void merge(forward_list&& x, Compare comp);
+ void sort();
+ template <class Compare> void sort(Compare comp);
+ void reverse() noexcept;
+};
+
+
+template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+ forward_list(InputIterator, InputIterator, Allocator = Allocator())
+ -> forward_list<typename iterator_traits<InputIterator>::value_type, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator = allocator<ranges::range_value_t<R>>>
+ forward_list(from_range_t, R&&, Allocator = Allocator())
+ -> forward_list<ranges::range_value_t<R>, Allocator>; // C++23
+
+template <class T, class Allocator>
+ bool operator==(const forward_list<T, Allocator>& x,
+ const forward_list<T, Allocator>& y);
+
+template <class T, class Allocator>
+ bool operator< (const forward_list<T, Allocator>& x,
+ const forward_list<T, Allocator>& y); // removed in C++20
+
+template <class T, class Allocator>
+ bool operator!=(const forward_list<T, Allocator>& x,
+ const forward_list<T, Allocator>& y); // removed in C++20
+
+template <class T, class Allocator>
+ bool operator> (const forward_list<T, Allocator>& x,
+ const forward_list<T, Allocator>& y); // removed in C++20
+
+template <class T, class Allocator>
+ bool operator>=(const forward_list<T, Allocator>& x,
+ const forward_list<T, Allocator>& y); // removed in C++20
+
+template <class T, class Allocator>
+ bool operator<=(const forward_list<T, Allocator>& x,
+ const forward_list<T, Allocator>& y); // removed in C++20
+
+template<class T, class Allocator>
+ synth-three-way-result<T> operator<=>(const forward_list<T, Allocator>& x,
+ const forward_list<T, Allocator>& y); // since C++20
+
+template <class T, class Allocator>
+ void swap(forward_list<T, Allocator>& x, forward_list<T, Allocator>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class T, class Allocator, class U>
+ typename forward_list<T, Allocator>::size_type
+ erase(forward_list<T, Allocator>& c, const U& value); // C++20
+template <class T, class Allocator, class Predicate>
+ typename forward_list<T, Allocator>::size_type
+ erase_if(forward_list<T, Allocator>& c, Predicate pred); // C++20
+
+} // std
+
+*/
+
+#include <__algorithm/comp.h>
+#include <__algorithm/lexicographical_compare.h>
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__algorithm/min.h>
+#include <__config>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/move_iterator.h>
+#include <__iterator/next.h>
+#include <__memory/addressof.h>
+#include <__memory/allocation_guard.h>
+#include <__memory/allocator.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/compressed_pair.h>
+#include <__memory/construct_at.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/swap_allocator.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_allocator.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <limits>
+#include <new> // __launder
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [forward.list.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _VoidPtr>
+struct __forward_list_node;
+template <class _NodePtr>
+struct __forward_begin_node;
+
+template <class>
+struct __forward_list_node_value_type;
+
+template <class _Tp, class _VoidPtr>
+struct __forward_list_node_value_type<__forward_list_node<_Tp, _VoidPtr> > {
+ typedef _Tp type;
+};
+
+template <class _NodePtr>
+struct __forward_node_traits {
+ typedef __remove_cv_t<typename pointer_traits<_NodePtr>::element_type> __node_type;
+ typedef typename __forward_list_node_value_type<__node_type>::type __node_value_type;
+ typedef _NodePtr __node_pointer;
+ typedef __forward_begin_node<_NodePtr> __begin_node;
+ typedef __rebind_pointer_t<_NodePtr, __begin_node> __begin_node_pointer;
+ typedef __rebind_pointer_t<_NodePtr, void> __void_pointer;
+
+#if defined(_LIBCPP_ABI_FORWARD_LIST_REMOVE_NODE_POINTER_UB)
+ typedef __begin_node_pointer __iter_node_pointer;
+#else
+ typedef __conditional_t<is_pointer<__void_pointer>::value, __begin_node_pointer, __node_pointer> __iter_node_pointer;
+#endif
+
+ typedef __conditional_t<is_same<__iter_node_pointer, __node_pointer>::value, __begin_node_pointer, __node_pointer>
+ __non_iter_node_pointer;
+
+ _LIBCPP_HIDE_FROM_ABI static __iter_node_pointer __as_iter_node(__iter_node_pointer __p) { return __p; }
+ _LIBCPP_HIDE_FROM_ABI static __iter_node_pointer __as_iter_node(__non_iter_node_pointer __p) {
+ return static_cast<__iter_node_pointer>(static_cast<__void_pointer>(__p));
+ }
+};
+
+template <class _NodePtr>
+struct __forward_begin_node {
+ typedef _NodePtr pointer;
+ typedef __rebind_pointer_t<_NodePtr, __forward_begin_node> __begin_node_pointer;
+
+ pointer __next_;
+
+ _LIBCPP_HIDE_FROM_ABI __forward_begin_node() : __next_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_begin_node(pointer __n) : __next_(__n) {}
+
+ _LIBCPP_HIDE_FROM_ABI __begin_node_pointer __next_as_begin() const {
+ return static_cast<__begin_node_pointer>(__next_);
+ }
+};
+
+template <class _Tp, class _VoidPtr>
+using __begin_node_of = __forward_begin_node<__rebind_pointer_t<_VoidPtr, __forward_list_node<_Tp, _VoidPtr> > >;
+
+template <class _Tp, class _VoidPtr>
+struct __forward_list_node : public __begin_node_of<_Tp, _VoidPtr> {
+ typedef _Tp value_type;
+ typedef __begin_node_of<_Tp, _VoidPtr> _Base;
+ typedef typename _Base::pointer _NodePtr;
+
+ // We allow starting the lifetime of nodes without initializing the value held by the node,
+ // since that is handled by the list itself in order to be allocator-aware.
+#ifndef _LIBCPP_CXX03_LANG
+
+private:
+ union {
+ _Tp __value_;
+ };
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _Tp& __get_value() { return __value_; }
+#else
+
+private:
+ _ALIGNAS_TYPE(_Tp) char __buffer_[sizeof(_Tp)];
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _Tp& __get_value() { return *std::__launder(reinterpret_cast<_Tp*>(&__buffer_)); }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_node(_NodePtr __next) : _Base(__next) {}
+ _LIBCPP_HIDE_FROM_ABI ~__forward_list_node() {}
+};
+
+template <class _Tp, class _Alloc = allocator<_Tp> >
+class _LIBCPP_TEMPLATE_VIS forward_list;
+template <class _NodeConstPtr>
+class _LIBCPP_TEMPLATE_VIS __forward_list_const_iterator;
+
+template <class _NodePtr>
+class _LIBCPP_TEMPLATE_VIS __forward_list_iterator {
+ typedef __forward_node_traits<_NodePtr> __traits;
+ typedef typename __traits::__node_pointer __node_pointer;
+ typedef typename __traits::__begin_node_pointer __begin_node_pointer;
+ typedef typename __traits::__iter_node_pointer __iter_node_pointer;
+ typedef typename __traits::__void_pointer __void_pointer;
+
+ __iter_node_pointer __ptr_;
+
+ _LIBCPP_HIDE_FROM_ABI __begin_node_pointer __get_begin() const {
+ return static_cast<__begin_node_pointer>(static_cast<__void_pointer>(__ptr_));
+ }
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __get_unsafe_node_pointer() const {
+ return static_cast<__node_pointer>(static_cast<__void_pointer>(__ptr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_iterator(nullptr_t) _NOEXCEPT : __ptr_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_iterator(__begin_node_pointer __p) _NOEXCEPT
+ : __ptr_(__traits::__as_iter_node(__p)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_iterator(__node_pointer __p) _NOEXCEPT
+ : __ptr_(__traits::__as_iter_node(__p)) {}
+
+ template <class, class>
+ friend class _LIBCPP_TEMPLATE_VIS forward_list;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __forward_list_const_iterator;
+
+public:
+ typedef forward_iterator_tag iterator_category;
+ typedef typename __traits::__node_value_type value_type;
+ typedef value_type& reference;
+ typedef typename pointer_traits<__node_pointer>::difference_type difference_type;
+ typedef __rebind_pointer_t<__node_pointer, value_type> pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __forward_list_iterator() _NOEXCEPT : __ptr_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __get_unsafe_node_pointer()->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const {
+ return pointer_traits<pointer>::pointer_to(__get_unsafe_node_pointer()->__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __forward_list_iterator& operator++() {
+ __ptr_ = __traits::__as_iter_node(__ptr_->__next_);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __forward_list_iterator operator++(int) {
+ __forward_list_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __forward_list_iterator& __x, const __forward_list_iterator& __y) {
+ return __x.__ptr_ == __y.__ptr_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __forward_list_iterator& __x, const __forward_list_iterator& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _NodeConstPtr>
+class _LIBCPP_TEMPLATE_VIS __forward_list_const_iterator {
+ static_assert(!is_const<typename pointer_traits<_NodeConstPtr>::element_type>::value, "");
+ typedef _NodeConstPtr _NodePtr;
+
+ typedef __forward_node_traits<_NodePtr> __traits;
+ typedef typename __traits::__node_type __node_type;
+ typedef typename __traits::__node_pointer __node_pointer;
+ typedef typename __traits::__begin_node_pointer __begin_node_pointer;
+ typedef typename __traits::__iter_node_pointer __iter_node_pointer;
+ typedef typename __traits::__void_pointer __void_pointer;
+
+ __iter_node_pointer __ptr_;
+
+ _LIBCPP_HIDE_FROM_ABI __begin_node_pointer __get_begin() const {
+ return static_cast<__begin_node_pointer>(static_cast<__void_pointer>(__ptr_));
+ }
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __get_unsafe_node_pointer() const {
+ return static_cast<__node_pointer>(static_cast<__void_pointer>(__ptr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_const_iterator(nullptr_t) _NOEXCEPT : __ptr_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_const_iterator(__begin_node_pointer __p) _NOEXCEPT
+ : __ptr_(__traits::__as_iter_node(__p)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_const_iterator(__node_pointer __p) _NOEXCEPT
+ : __ptr_(__traits::__as_iter_node(__p)) {}
+
+ template <class, class>
+ friend class forward_list;
+
+public:
+ typedef forward_iterator_tag iterator_category;
+ typedef typename __traits::__node_value_type value_type;
+ typedef const value_type& reference;
+ typedef typename pointer_traits<__node_pointer>::difference_type difference_type;
+ typedef __rebind_pointer_t<__node_pointer, const value_type> pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __forward_list_const_iterator() _NOEXCEPT : __ptr_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI __forward_list_const_iterator(__forward_list_iterator<__node_pointer> __p) _NOEXCEPT
+ : __ptr_(__p.__ptr_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __get_unsafe_node_pointer()->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const {
+ return pointer_traits<pointer>::pointer_to(__get_unsafe_node_pointer()->__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __forward_list_const_iterator& operator++() {
+ __ptr_ = __traits::__as_iter_node(__ptr_->__next_);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __forward_list_const_iterator operator++(int) {
+ __forward_list_const_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const __forward_list_const_iterator& __x, const __forward_list_const_iterator& __y) {
+ return __x.__ptr_ == __y.__ptr_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const __forward_list_const_iterator& __x, const __forward_list_const_iterator& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _Tp, class _Alloc>
+class __forward_list_base {
+protected:
+ typedef _Tp value_type;
+ typedef _Alloc allocator_type;
+
+ typedef typename allocator_traits<allocator_type>::void_pointer void_pointer;
+ typedef __forward_list_node<value_type, void_pointer> __node_type;
+ typedef __begin_node_of<value_type, void_pointer> __begin_node;
+ typedef __rebind_alloc<allocator_traits<allocator_type>, __node_type> __node_allocator;
+ typedef allocator_traits<__node_allocator> __node_traits;
+ typedef typename __node_traits::pointer __node_pointer;
+
+ typedef __rebind_alloc<allocator_traits<allocator_type>, __begin_node> __begin_node_allocator;
+ typedef typename allocator_traits<__begin_node_allocator>::pointer __begin_node_pointer;
+
+ __compressed_pair<__begin_node, __node_allocator> __before_begin_;
+
+ _LIBCPP_HIDE_FROM_ABI __begin_node_pointer __before_begin() _NOEXCEPT {
+ return pointer_traits<__begin_node_pointer>::pointer_to(__before_begin_.first());
+ }
+ _LIBCPP_HIDE_FROM_ABI __begin_node_pointer __before_begin() const _NOEXCEPT {
+ return pointer_traits<__begin_node_pointer>::pointer_to(const_cast<__begin_node&>(__before_begin_.first()));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __node_allocator& __alloc() _NOEXCEPT { return __before_begin_.second(); }
+ _LIBCPP_HIDE_FROM_ABI const __node_allocator& __alloc() const _NOEXCEPT { return __before_begin_.second(); }
+
+ typedef __forward_list_iterator<__node_pointer> iterator;
+ typedef __forward_list_const_iterator<__node_pointer> const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI __forward_list_base() _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value)
+ : __before_begin_(__begin_node(), __default_init_tag()) {}
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_base(const allocator_type& __a)
+ : __before_begin_(__begin_node(), __node_allocator(__a)) {}
+ _LIBCPP_HIDE_FROM_ABI explicit __forward_list_base(const __node_allocator& __a)
+ : __before_begin_(__begin_node(), __a) {}
+
+public:
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI
+ __forward_list_base(__forward_list_base&& __x) noexcept(is_nothrow_move_constructible<__node_allocator>::value);
+ _LIBCPP_HIDE_FROM_ABI __forward_list_base(__forward_list_base&& __x, const allocator_type& __a);
+#endif // _LIBCPP_CXX03_LANG
+
+ __forward_list_base(const __forward_list_base&) = delete;
+ __forward_list_base& operator=(const __forward_list_base&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI ~__forward_list_base();
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __forward_list_base& __x) {
+ __copy_assign_alloc(__x, integral_constant<bool, __node_traits::propagate_on_container_copy_assignment::value>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__forward_list_base& __x)
+ _NOEXCEPT_(!__node_traits::propagate_on_container_move_assignment::value ||
+ is_nothrow_move_assignable<__node_allocator>::value) {
+ __move_assign_alloc(__x, integral_constant<bool, __node_traits::propagate_on_container_move_assignment::value>());
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __create_node(__node_pointer __next, _Args&&... __args) {
+ __node_allocator& __a = __alloc();
+ __allocation_guard<__node_allocator> __guard(__a, 1);
+ // Begin the lifetime of the node itself. Note that this doesn't begin the lifetime of the value
+ // held inside the node, since we need to use the allocator's construct() method for that.
+ //
+ // We don't use the allocator's construct() method to construct the node itself since the
+ // Cpp17FooInsertable named requirements don't require the allocator's construct() method
+ // to work on anything other than the value_type.
+ std::__construct_at(std::addressof(*__guard.__get()), __next);
+
+ // Now construct the value_type using the allocator's construct() method.
+ __node_traits::construct(__a, std::addressof(__guard.__get()->__get_value()), std::forward<_Args>(__args)...);
+ return __guard.__release_ptr();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __delete_node(__node_pointer __node) {
+ // For the same reason as above, we use the allocator's destroy() method for the value_type,
+ // but not for the node itself.
+ __node_allocator& __a = __alloc();
+ __node_traits::destroy(__a, std::addressof(__node->__get_value()));
+ std::__destroy_at(std::addressof(*__node));
+ __node_traits::deallocate(__a, __node, 1);
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI void swap(__forward_list_base& __x)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT;
+#else
+ _NOEXCEPT_(!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>);
+#endif
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT;
+
+private:
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __forward_list_base&, false_type) {}
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __forward_list_base& __x, true_type) {
+ if (__alloc() != __x.__alloc())
+ clear();
+ __alloc() = __x.__alloc();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__forward_list_base&, false_type) _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__forward_list_base& __x, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value) {
+ __alloc() = std::move(__x.__alloc());
+ }
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+inline __forward_list_base<_Tp, _Alloc>::__forward_list_base(__forward_list_base&& __x) noexcept(
+ is_nothrow_move_constructible<__node_allocator>::value)
+ : __before_begin_(std::move(__x.__before_begin_)) {
+ __x.__before_begin()->__next_ = nullptr;
+}
+
+template <class _Tp, class _Alloc>
+inline __forward_list_base<_Tp, _Alloc>::__forward_list_base(__forward_list_base&& __x, const allocator_type& __a)
+ : __before_begin_(__begin_node(), __node_allocator(__a)) {
+ if (__alloc() == __x.__alloc()) {
+ __before_begin()->__next_ = __x.__before_begin()->__next_;
+ __x.__before_begin()->__next_ = nullptr;
+ }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+__forward_list_base<_Tp, _Alloc>::~__forward_list_base() {
+ clear();
+}
+
+template <class _Tp, class _Alloc>
+inline void __forward_list_base<_Tp, _Alloc>::swap(__forward_list_base& __x)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>)
+#endif
+{
+ std::__swap_allocator(
+ __alloc(), __x.__alloc(), integral_constant<bool, __node_traits::propagate_on_container_swap::value>());
+ using std::swap;
+ swap(__before_begin()->__next_, __x.__before_begin()->__next_);
+}
+
+template <class _Tp, class _Alloc>
+void __forward_list_base<_Tp, _Alloc>::clear() _NOEXCEPT {
+ for (__node_pointer __p = __before_begin()->__next_; __p != nullptr;) {
+ __node_pointer __next = __p->__next_;
+ __delete_node(__p);
+ __p = __next;
+ }
+ __before_begin()->__next_ = nullptr;
+}
+
+template <class _Tp, class _Alloc /*= allocator<_Tp>*/>
+class _LIBCPP_TEMPLATE_VIS forward_list : private __forward_list_base<_Tp, _Alloc> {
+ typedef __forward_list_base<_Tp, _Alloc> base;
+ typedef typename base::__node_allocator __node_allocator;
+ typedef typename base::__node_type __node_type;
+ typedef typename base::__node_traits __node_traits;
+ typedef typename base::__node_pointer __node_pointer;
+ typedef typename base::__begin_node_pointer __begin_node_pointer;
+
+public:
+ typedef _Tp value_type;
+ typedef _Alloc allocator_type;
+
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+
+ static_assert(is_same<value_type, typename allocator_type::value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+ static_assert(!is_same<allocator_type, __node_allocator>::value,
+ "internal allocator type must differ from user-specified type; otherwise overload resolution breaks");
+
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef typename base::iterator iterator;
+ typedef typename base::const_iterator const_iterator;
+#if _LIBCPP_STD_VER >= 20
+ typedef size_type __remove_return_type;
+#else
+ typedef void __remove_return_type;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI forward_list() _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value) {
+ } // = default;
+ _LIBCPP_HIDE_FROM_ABI explicit forward_list(const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI explicit forward_list(size_type __n);
+#if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI explicit forward_list(size_type __n, const allocator_type& __a);
+#endif
+ _LIBCPP_HIDE_FROM_ABI forward_list(size_type __n, const value_type& __v);
+
+ template <__enable_if_t<__is_allocator<_Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI forward_list(size_type __n, const value_type& __v, const allocator_type& __a) : base(__a) {
+ insert_after(cbefore_begin(), __n, __v);
+ }
+
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI forward_list(_InputIterator __f, _InputIterator __l);
+
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI forward_list(_InputIterator __f, _InputIterator __l, const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI forward_list(from_range_t, _Range&& __range, const allocator_type& __a = allocator_type())
+ : base(__a) {
+ prepend_range(std::forward<_Range>(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI forward_list(const forward_list& __x);
+ _LIBCPP_HIDE_FROM_ABI forward_list(const forward_list& __x, const __type_identity_t<allocator_type>& __a);
+
+ _LIBCPP_HIDE_FROM_ABI forward_list& operator=(const forward_list& __x);
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI forward_list(forward_list&& __x) noexcept(is_nothrow_move_constructible<base>::value)
+ : base(std::move(__x)) {}
+ _LIBCPP_HIDE_FROM_ABI forward_list(forward_list&& __x, const __type_identity_t<allocator_type>& __a);
+
+ _LIBCPP_HIDE_FROM_ABI forward_list(initializer_list<value_type> __il);
+ _LIBCPP_HIDE_FROM_ABI forward_list(initializer_list<value_type> __il, const allocator_type& __a);
+
+ _LIBCPP_HIDE_FROM_ABI forward_list& operator=(forward_list&& __x) noexcept(
+ __node_traits::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value);
+
+ _LIBCPP_HIDE_FROM_ABI forward_list& operator=(initializer_list<value_type> __il);
+
+ _LIBCPP_HIDE_FROM_ABI void assign(initializer_list<value_type> __il);
+#endif // _LIBCPP_CXX03_LANG
+
+ // ~forward_list() = default;
+
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI assign(_InputIterator __f, _InputIterator __l);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void assign_range(_Range&& __range) {
+ __assign_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void assign(size_type __n, const value_type& __v);
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT { return allocator_type(base::__alloc()); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return iterator(base::__before_begin()->__next_); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT {
+ return const_iterator(base::__before_begin()->__next_);
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return iterator(nullptr); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return const_iterator(nullptr); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT {
+ return const_iterator(base::__before_begin()->__next_);
+ }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return const_iterator(nullptr); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator before_begin() _NOEXCEPT { return iterator(base::__before_begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator before_begin() const _NOEXCEPT { return const_iterator(base::__before_begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbefore_begin() const _NOEXCEPT {
+ return const_iterator(base::__before_begin());
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT {
+ return base::__before_begin()->__next_ == nullptr;
+ }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT {
+ return std::min<size_type>(__node_traits::max_size(base::__alloc()), numeric_limits<difference_type>::max());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI reference front() { return base::__before_begin()->__next_->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI const_reference front() const { return base::__before_begin()->__next_->__get_value(); }
+
+#ifndef _LIBCPP_CXX03_LANG
+# if _LIBCPP_STD_VER >= 17
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI reference emplace_front(_Args&&... __args);
+# else
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void emplace_front(_Args&&... __args);
+# endif
+ _LIBCPP_HIDE_FROM_ABI void push_front(value_type&& __v);
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void push_front(const value_type& __v);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void prepend_range(_Range&& __range) {
+ insert_range_after(cbefore_begin(), std::forward<_Range>(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void pop_front();
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_after(const_iterator __p, _Args&&... __args);
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert_after(const_iterator __p, value_type&& __v);
+ _LIBCPP_HIDE_FROM_ABI iterator insert_after(const_iterator __p, initializer_list<value_type> __il) {
+ return insert_after(__p, __il.begin(), __il.end());
+ }
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI iterator insert_after(const_iterator __p, const value_type& __v);
+ _LIBCPP_HIDE_FROM_ABI iterator insert_after(const_iterator __p, size_type __n, const value_type& __v);
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_after(const_iterator __p, _InputIterator __f, _InputIterator __l);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_range_after(const_iterator __position, _Range&& __range) {
+ return __insert_after_with_sentinel(__position, ranges::begin(__range), ranges::end(__range));
+ }
+#endif
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_after_with_sentinel(const_iterator __p, _InputIterator __f, _Sentinel __l);
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase_after(const_iterator __p);
+ _LIBCPP_HIDE_FROM_ABI iterator erase_after(const_iterator __f, const_iterator __l);
+
+ _LIBCPP_HIDE_FROM_ABI void swap(forward_list& __x)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>)
+#endif
+ {
+ base::swap(__x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n);
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n, const value_type& __v);
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { base::clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI void splice_after(const_iterator __p, forward_list&& __x);
+ _LIBCPP_HIDE_FROM_ABI void splice_after(const_iterator __p, forward_list&& __x, const_iterator __i);
+ _LIBCPP_HIDE_FROM_ABI void
+ splice_after(const_iterator __p, forward_list&& __x, const_iterator __f, const_iterator __l);
+ _LIBCPP_HIDE_FROM_ABI void splice_after(const_iterator __p, forward_list& __x);
+ _LIBCPP_HIDE_FROM_ABI void splice_after(const_iterator __p, forward_list& __x, const_iterator __i);
+ _LIBCPP_HIDE_FROM_ABI void
+ splice_after(const_iterator __p, forward_list& __x, const_iterator __f, const_iterator __l);
+ _LIBCPP_HIDE_FROM_ABI __remove_return_type remove(const value_type& __v);
+ template <class _Predicate>
+ _LIBCPP_HIDE_FROM_ABI __remove_return_type remove_if(_Predicate __pred);
+ _LIBCPP_HIDE_FROM_ABI __remove_return_type unique() { return unique(__equal_to()); }
+ template <class _BinaryPredicate>
+ _LIBCPP_HIDE_FROM_ABI __remove_return_type unique(_BinaryPredicate __binary_pred);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void merge(forward_list&& __x) { merge(__x, __less<>()); }
+ template <class _Compare>
+ _LIBCPP_HIDE_FROM_ABI void merge(forward_list&& __x, _Compare __comp) {
+ merge(__x, std::move(__comp));
+ }
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void merge(forward_list& __x) { merge(__x, __less<>()); }
+ template <class _Compare>
+ _LIBCPP_HIDE_FROM_ABI void merge(forward_list& __x, _Compare __comp);
+ _LIBCPP_HIDE_FROM_ABI void sort() { sort(__less<>()); }
+ template <class _Compare>
+ _LIBCPP_HIDE_FROM_ABI void sort(_Compare __comp);
+ _LIBCPP_HIDE_FROM_ABI void reverse() _NOEXCEPT;
+
+private:
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(forward_list& __x, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(forward_list& __x, false_type);
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class _Iter, class _Sent>
+ _LIBCPP_HIDE_FROM_ABI void __assign_with_sentinel(_Iter __f, _Sent __l);
+
+ template <class _Compare>
+ static _LIBCPP_HIDE_FROM_ABI __node_pointer __merge(__node_pointer __f1, __node_pointer __f2, _Compare& __comp);
+
+ // TODO: Make this _LIBCPP_HIDE_FROM_ABI
+ template <class _Compare>
+ static _LIBCPP_HIDDEN __node_pointer __sort(__node_pointer __f, difference_type __sz, _Compare& __comp);
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Alloc = allocator<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+forward_list(_InputIterator, _InputIterator) -> forward_list<__iter_value_type<_InputIterator>, _Alloc>;
+
+template <class _InputIterator,
+ class _Alloc,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+forward_list(_InputIterator, _InputIterator, _Alloc) -> forward_list<__iter_value_type<_InputIterator>, _Alloc>;
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Alloc = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+forward_list(from_range_t, _Range&&, _Alloc = _Alloc()) -> forward_list<ranges::range_value_t<_Range>, _Alloc>;
+#endif
+
+template <class _Tp, class _Alloc>
+inline forward_list<_Tp, _Alloc>::forward_list(const allocator_type& __a) : base(__a) {}
+
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>::forward_list(size_type __n) {
+ if (__n > 0) {
+ for (__begin_node_pointer __p = base::__before_begin(); __n > 0; --__n, __p = __p->__next_as_begin()) {
+ __p->__next_ = this->__create_node(/* next = */ nullptr);
+ }
+ }
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>::forward_list(size_type __n, const allocator_type& __base_alloc) : base(__base_alloc) {
+ if (__n > 0) {
+ for (__begin_node_pointer __p = base::__before_begin(); __n > 0; --__n, __p = __p->__next_as_begin()) {
+ __p->__next_ = this->__create_node(/* next = */ nullptr);
+ }
+ }
+}
+#endif
+
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>::forward_list(size_type __n, const value_type& __v) {
+ insert_after(cbefore_begin(), __n, __v);
+}
+
+template <class _Tp, class _Alloc>
+template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> >
+forward_list<_Tp, _Alloc>::forward_list(_InputIterator __f, _InputIterator __l) {
+ insert_after(cbefore_begin(), __f, __l);
+}
+
+template <class _Tp, class _Alloc>
+template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> >
+forward_list<_Tp, _Alloc>::forward_list(_InputIterator __f, _InputIterator __l, const allocator_type& __a) : base(__a) {
+ insert_after(cbefore_begin(), __f, __l);
+}
+
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>::forward_list(const forward_list& __x)
+ : base(__node_traits::select_on_container_copy_construction(__x.__alloc())) {
+ insert_after(cbefore_begin(), __x.begin(), __x.end());
+}
+
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>::forward_list(const forward_list& __x, const __type_identity_t<allocator_type>& __a)
+ : base(__a) {
+ insert_after(cbefore_begin(), __x.begin(), __x.end());
+}
+
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>& forward_list<_Tp, _Alloc>::operator=(const forward_list& __x) {
+ if (this != std::addressof(__x)) {
+ base::__copy_assign_alloc(__x);
+ assign(__x.begin(), __x.end());
+ }
+ return *this;
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>::forward_list(forward_list&& __x, const __type_identity_t<allocator_type>& __a)
+ : base(std::move(__x), __a) {
+ if (base::__alloc() != __x.__alloc()) {
+ typedef move_iterator<iterator> _Ip;
+ insert_after(cbefore_begin(), _Ip(__x.begin()), _Ip(__x.end()));
+ }
+}
+
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>::forward_list(initializer_list<value_type> __il) {
+ insert_after(cbefore_begin(), __il.begin(), __il.end());
+}
+
+template <class _Tp, class _Alloc>
+forward_list<_Tp, _Alloc>::forward_list(initializer_list<value_type> __il, const allocator_type& __a) : base(__a) {
+ insert_after(cbefore_begin(), __il.begin(), __il.end());
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::__move_assign(forward_list& __x, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
+ clear();
+ base::__move_assign_alloc(__x);
+ base::__before_begin()->__next_ = __x.__before_begin()->__next_;
+ __x.__before_begin()->__next_ = nullptr;
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::__move_assign(forward_list& __x, false_type) {
+ if (base::__alloc() == __x.__alloc())
+ __move_assign(__x, true_type());
+ else {
+ typedef move_iterator<iterator> _Ip;
+ assign(_Ip(__x.begin()), _Ip(__x.end()));
+ }
+}
+
+template <class _Tp, class _Alloc>
+inline forward_list<_Tp, _Alloc>& forward_list<_Tp, _Alloc>::operator=(forward_list&& __x) _NOEXCEPT_(
+ __node_traits::propagate_on_container_move_assignment::value&& is_nothrow_move_assignable<allocator_type>::value) {
+ __move_assign(__x, integral_constant<bool, __node_traits::propagate_on_container_move_assignment::value>());
+ return *this;
+}
+
+template <class _Tp, class _Alloc>
+inline forward_list<_Tp, _Alloc>& forward_list<_Tp, _Alloc>::operator=(initializer_list<value_type> __il) {
+ assign(__il.begin(), __il.end());
+ return *this;
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> >
+void forward_list<_Tp, _Alloc>::assign(_InputIterator __f, _InputIterator __l) {
+ __assign_with_sentinel(__f, __l);
+}
+
+template <class _Tp, class _Alloc>
+template <class _Iter, class _Sent>
+_LIBCPP_HIDE_FROM_ABI void forward_list<_Tp, _Alloc>::__assign_with_sentinel(_Iter __f, _Sent __l) {
+ iterator __i = before_begin();
+ iterator __j = std::next(__i);
+ iterator __e = end();
+ for (; __j != __e && __f != __l; ++__i, (void)++__j, ++__f)
+ *__j = *__f;
+ if (__j == __e)
+ __insert_after_with_sentinel(__i, std::move(__f), std::move(__l));
+ else
+ erase_after(__i, __e);
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::assign(size_type __n, const value_type& __v) {
+ iterator __i = before_begin();
+ iterator __j = std::next(__i);
+ iterator __e = end();
+ for (; __j != __e && __n > 0; --__n, ++__i, ++__j)
+ *__j = __v;
+ if (__j == __e)
+ insert_after(__i, __n, __v);
+ else
+ erase_after(__i, __e);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+inline void forward_list<_Tp, _Alloc>::assign(initializer_list<value_type> __il) {
+ assign(__il.begin(), __il.end());
+}
+
+template <class _Tp, class _Alloc>
+template <class... _Args>
+# if _LIBCPP_STD_VER >= 17
+typename forward_list<_Tp, _Alloc>::reference
+# else
+void
+# endif
+forward_list<_Tp, _Alloc>::emplace_front(_Args&&... __args) {
+ base::__before_begin()->__next_ =
+ this->__create_node(/* next = */ base::__before_begin()->__next_, std::forward<_Args>(__args)...);
+# if _LIBCPP_STD_VER >= 17
+ return base::__before_begin()->__next_->__get_value();
+# endif
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::push_front(value_type&& __v) {
+ base::__before_begin()->__next_ = this->__create_node(/* next = */ base::__before_begin()->__next_, std::move(__v));
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::push_front(const value_type& __v) {
+ base::__before_begin()->__next_ = this->__create_node(/* next = */ base::__before_begin()->__next_, __v);
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::pop_front() {
+ __node_pointer __p = base::__before_begin()->__next_;
+ base::__before_begin()->__next_ = __p->__next_;
+ this->__delete_node(__p);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+template <class... _Args>
+typename forward_list<_Tp, _Alloc>::iterator
+forward_list<_Tp, _Alloc>::emplace_after(const_iterator __p, _Args&&... __args) {
+ __begin_node_pointer const __r = __p.__get_begin();
+ __r->__next_ = this->__create_node(/* next = */ __r->__next_, std::forward<_Args>(__args)...);
+ return iterator(__r->__next_);
+}
+
+template <class _Tp, class _Alloc>
+typename forward_list<_Tp, _Alloc>::iterator
+forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, value_type&& __v) {
+ __begin_node_pointer const __r = __p.__get_begin();
+ __r->__next_ = this->__create_node(/* next = */ __r->__next_, std::move(__v));
+ return iterator(__r->__next_);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+typename forward_list<_Tp, _Alloc>::iterator
+forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, const value_type& __v) {
+ __begin_node_pointer const __r = __p.__get_begin();
+ __r->__next_ = this->__create_node(/* next = */ __r->__next_, __v);
+ return iterator(__r->__next_);
+}
+
+template <class _Tp, class _Alloc>
+typename forward_list<_Tp, _Alloc>::iterator
+forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, size_type __n, const value_type& __v) {
+ __begin_node_pointer __r = __p.__get_begin();
+ if (__n > 0) {
+ __node_pointer __first = this->__create_node(/* next = */ nullptr, __v);
+ __node_pointer __last = __first;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (--__n; __n != 0; --__n, __last = __last->__next_) {
+ __last->__next_ = this->__create_node(/* next = */ nullptr, __v);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ while (__first != nullptr) {
+ __node_pointer __next = __first->__next_;
+ this->__delete_node(__first);
+ __first = __next;
+ }
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __last->__next_ = __r->__next_;
+ __r->__next_ = __first;
+ __r = static_cast<__begin_node_pointer>(__last);
+ }
+ return iterator(__r);
+}
+
+template <class _Tp, class _Alloc>
+template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> >
+typename forward_list<_Tp, _Alloc>::iterator
+forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, _InputIterator __f, _InputIterator __l) {
+ return __insert_after_with_sentinel(__p, std::move(__f), std::move(__l));
+}
+
+template <class _Tp, class _Alloc>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI typename forward_list<_Tp, _Alloc>::iterator
+forward_list<_Tp, _Alloc>::__insert_after_with_sentinel(const_iterator __p, _InputIterator __f, _Sentinel __l) {
+ __begin_node_pointer __r = __p.__get_begin();
+
+ if (__f != __l) {
+ __node_pointer __first = this->__create_node(/* next = */ nullptr, *__f);
+ __node_pointer __last = __first;
+
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (++__f; __f != __l; ++__f, ((void)(__last = __last->__next_))) {
+ __last->__next_ = this->__create_node(/* next = */ nullptr, *__f);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ while (__first != nullptr) {
+ __node_pointer __next = __first->__next_;
+ this->__delete_node(__first);
+ __first = __next;
+ }
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+
+ __last->__next_ = __r->__next_;
+ __r->__next_ = __first;
+ __r = static_cast<__begin_node_pointer>(__last);
+ }
+
+ return iterator(__r);
+}
+
+template <class _Tp, class _Alloc>
+typename forward_list<_Tp, _Alloc>::iterator forward_list<_Tp, _Alloc>::erase_after(const_iterator __f) {
+ __begin_node_pointer __p = __f.__get_begin();
+ __node_pointer __n = __p->__next_;
+ __p->__next_ = __n->__next_;
+ this->__delete_node(__n);
+ return iterator(__p->__next_);
+}
+
+template <class _Tp, class _Alloc>
+typename forward_list<_Tp, _Alloc>::iterator
+forward_list<_Tp, _Alloc>::erase_after(const_iterator __f, const_iterator __l) {
+ __node_pointer __e = __l.__get_unsafe_node_pointer();
+ if (__f != __l) {
+ __begin_node_pointer __bp = __f.__get_begin();
+
+ __node_pointer __n = __bp->__next_;
+ if (__n != __e) {
+ __bp->__next_ = __e;
+ do {
+ __node_pointer __tmp = __n->__next_;
+ this->__delete_node(__n);
+ __n = __tmp;
+ } while (__n != __e);
+ }
+ }
+ return iterator(__e);
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::resize(size_type __n) {
+ size_type __sz = 0;
+ iterator __p = before_begin();
+ iterator __i = begin();
+ iterator __e = end();
+ for (; __i != __e && __sz < __n; ++__p, ++__i, ++__sz)
+ ;
+ if (__i != __e)
+ erase_after(__p, __e);
+ else {
+ __n -= __sz;
+ if (__n > 0) {
+ for (__begin_node_pointer __ptr = __p.__get_begin(); __n > 0; --__n, __ptr = __ptr->__next_as_begin()) {
+ __ptr->__next_ = this->__create_node(/* next = */ nullptr);
+ }
+ }
+ }
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::resize(size_type __n, const value_type& __v) {
+ size_type __sz = 0;
+ iterator __p = before_begin();
+ iterator __i = begin();
+ iterator __e = end();
+ for (; __i != __e && __sz < __n; ++__p, ++__i, ++__sz)
+ ;
+ if (__i != __e)
+ erase_after(__p, __e);
+ else {
+ __n -= __sz;
+ if (__n > 0) {
+ for (__begin_node_pointer __ptr = __p.__get_begin(); __n > 0; --__n, __ptr = __ptr->__next_as_begin()) {
+ __ptr->__next_ = this->__create_node(/* next = */ nullptr, __v);
+ }
+ }
+ }
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::splice_after(const_iterator __p, forward_list& __x) {
+ if (!__x.empty()) {
+ if (__p.__get_begin()->__next_ != nullptr) {
+ const_iterator __lm1 = __x.before_begin();
+ while (__lm1.__get_begin()->__next_ != nullptr)
+ ++__lm1;
+ __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
+ }
+ __p.__get_begin()->__next_ = __x.__before_begin()->__next_;
+ __x.__before_begin()->__next_ = nullptr;
+ }
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::splice_after(const_iterator __p, forward_list& /*__other*/, const_iterator __i) {
+ const_iterator __lm1 = std::next(__i);
+ if (__p != __i && __p != __lm1) {
+ __i.__get_begin()->__next_ = __lm1.__get_begin()->__next_;
+ __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
+ __p.__get_begin()->__next_ = __lm1.__get_unsafe_node_pointer();
+ }
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::splice_after(
+ const_iterator __p, forward_list& /*__other*/, const_iterator __f, const_iterator __l) {
+ if (__f != __l && __p != __f) {
+ const_iterator __lm1 = __f;
+ while (__lm1.__get_begin()->__next_ != __l.__get_begin())
+ ++__lm1;
+ if (__f != __lm1) {
+ __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
+ __p.__get_begin()->__next_ = __f.__get_begin()->__next_;
+ __f.__get_begin()->__next_ = __l.__get_unsafe_node_pointer();
+ }
+ }
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void forward_list<_Tp, _Alloc>::splice_after(const_iterator __p, forward_list&& __x) {
+ splice_after(__p, __x);
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+forward_list<_Tp, _Alloc>::splice_after(const_iterator __p, forward_list&& __x, const_iterator __i) {
+ splice_after(__p, __x, __i);
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void forward_list<_Tp, _Alloc>::splice_after(
+ const_iterator __p, forward_list&& __x, const_iterator __f, const_iterator __l) {
+ splice_after(__p, __x, __f, __l);
+}
+
+template <class _Tp, class _Alloc>
+typename forward_list<_Tp, _Alloc>::__remove_return_type forward_list<_Tp, _Alloc>::remove(const value_type& __v) {
+ forward_list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
+ typename forward_list<_Tp, _Alloc>::size_type __count_removed = 0;
+ const iterator __e = end();
+ for (iterator __i = before_begin(); __i.__get_begin()->__next_ != nullptr;) {
+ if (__i.__get_begin()->__next_->__get_value() == __v) {
+ ++__count_removed;
+ iterator __j = std::next(__i, 2);
+ for (; __j != __e && *__j == __v; ++__j)
+ ++__count_removed;
+ __deleted_nodes.splice_after(__deleted_nodes.before_begin(), *this, __i, __j);
+ if (__j == __e)
+ break;
+ __i = __j;
+ } else
+ ++__i;
+ }
+
+ return (__remove_return_type)__count_removed;
+}
+
+template <class _Tp, class _Alloc>
+template <class _Predicate>
+typename forward_list<_Tp, _Alloc>::__remove_return_type forward_list<_Tp, _Alloc>::remove_if(_Predicate __pred) {
+ forward_list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
+ typename forward_list<_Tp, _Alloc>::size_type __count_removed = 0;
+ const iterator __e = end();
+ for (iterator __i = before_begin(); __i.__get_begin()->__next_ != nullptr;) {
+ if (__pred(__i.__get_begin()->__next_->__get_value())) {
+ ++__count_removed;
+ iterator __j = std::next(__i, 2);
+ for (; __j != __e && __pred(*__j); ++__j)
+ ++__count_removed;
+ __deleted_nodes.splice_after(__deleted_nodes.before_begin(), *this, __i, __j);
+ if (__j == __e)
+ break;
+ __i = __j;
+ } else
+ ++__i;
+ }
+
+ return (__remove_return_type)__count_removed;
+}
+
+template <class _Tp, class _Alloc>
+template <class _BinaryPredicate>
+typename forward_list<_Tp, _Alloc>::__remove_return_type
+forward_list<_Tp, _Alloc>::unique(_BinaryPredicate __binary_pred) {
+ forward_list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
+ typename forward_list<_Tp, _Alloc>::size_type __count_removed = 0;
+ for (iterator __i = begin(), __e = end(); __i != __e;) {
+ iterator __j = std::next(__i);
+ for (; __j != __e && __binary_pred(*__i, *__j); ++__j)
+ ++__count_removed;
+ if (__i.__get_begin()->__next_ != __j.__get_unsafe_node_pointer())
+ __deleted_nodes.splice_after(__deleted_nodes.before_begin(), *this, __i, __j);
+ __i = __j;
+ }
+
+ return (__remove_return_type)__count_removed;
+}
+
+template <class _Tp, class _Alloc>
+template <class _Compare>
+void forward_list<_Tp, _Alloc>::merge(forward_list& __x, _Compare __comp) {
+ if (this != std::addressof(__x)) {
+ base::__before_begin()->__next_ = __merge(base::__before_begin()->__next_, __x.__before_begin()->__next_, __comp);
+ __x.__before_begin()->__next_ = nullptr;
+ }
+}
+
+template <class _Tp, class _Alloc>
+template <class _Compare>
+typename forward_list<_Tp, _Alloc>::__node_pointer
+forward_list<_Tp, _Alloc>::__merge(__node_pointer __f1, __node_pointer __f2, _Compare& __comp) {
+ if (__f1 == nullptr)
+ return __f2;
+ if (__f2 == nullptr)
+ return __f1;
+ __node_pointer __r;
+ if (__comp(__f2->__get_value(), __f1->__get_value())) {
+ __node_pointer __t = __f2;
+ while (__t->__next_ != nullptr && __comp(__t->__next_->__get_value(), __f1->__get_value()))
+ __t = __t->__next_;
+ __r = __f2;
+ __f2 = __t->__next_;
+ __t->__next_ = __f1;
+ } else
+ __r = __f1;
+ __node_pointer __p = __f1;
+ __f1 = __f1->__next_;
+ while (__f1 != nullptr && __f2 != nullptr) {
+ if (__comp(__f2->__get_value(), __f1->__get_value())) {
+ __node_pointer __t = __f2;
+ while (__t->__next_ != nullptr && __comp(__t->__next_->__get_value(), __f1->__get_value()))
+ __t = __t->__next_;
+ __p->__next_ = __f2;
+ __f2 = __t->__next_;
+ __t->__next_ = __f1;
+ }
+ __p = __f1;
+ __f1 = __f1->__next_;
+ }
+ if (__f2 != nullptr)
+ __p->__next_ = __f2;
+ return __r;
+}
+
+template <class _Tp, class _Alloc>
+template <class _Compare>
+inline void forward_list<_Tp, _Alloc>::sort(_Compare __comp) {
+ base::__before_begin()->__next_ = __sort(base::__before_begin()->__next_, std::distance(begin(), end()), __comp);
+}
+
+template <class _Tp, class _Alloc>
+template <class _Compare>
+typename forward_list<_Tp, _Alloc>::__node_pointer
+forward_list<_Tp, _Alloc>::__sort(__node_pointer __f1, difference_type __sz, _Compare& __comp) {
+ switch (__sz) {
+ case 0:
+ case 1:
+ return __f1;
+ case 2:
+ if (__comp(__f1->__next_->__get_value(), __f1->__get_value())) {
+ __node_pointer __t = __f1->__next_;
+ __t->__next_ = __f1;
+ __f1->__next_ = nullptr;
+ __f1 = __t;
+ }
+ return __f1;
+ }
+ difference_type __sz1 = __sz / 2;
+ difference_type __sz2 = __sz - __sz1;
+ __node_pointer __t = std::next(iterator(__f1), __sz1 - 1).__get_unsafe_node_pointer();
+ __node_pointer __f2 = __t->__next_;
+ __t->__next_ = nullptr;
+ return __merge(__sort(__f1, __sz1, __comp), __sort(__f2, __sz2, __comp), __comp);
+}
+
+template <class _Tp, class _Alloc>
+void forward_list<_Tp, _Alloc>::reverse() _NOEXCEPT {
+ __node_pointer __p = base::__before_begin()->__next_;
+ if (__p != nullptr) {
+ __node_pointer __f = __p->__next_;
+ __p->__next_ = nullptr;
+ while (__f != nullptr) {
+ __node_pointer __t = __f->__next_;
+ __f->__next_ = __p;
+ __p = __f;
+ __f = __t;
+ }
+ base::__before_begin()->__next_ = __p;
+ }
+}
+
+template <class _Tp, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const forward_list<_Tp, _Alloc>& __x, const forward_list<_Tp, _Alloc>& __y) {
+ typedef forward_list<_Tp, _Alloc> _Cp;
+ typedef typename _Cp::const_iterator _Ip;
+ _Ip __ix = __x.begin();
+ _Ip __ex = __x.end();
+ _Ip __iy = __y.begin();
+ _Ip __ey = __y.end();
+ for (; __ix != __ex && __iy != __ey; ++__ix, ++__iy)
+ if (!(*__ix == *__iy))
+ return false;
+ return (__ix == __ex) == (__iy == __ey);
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const forward_list<_Tp, _Alloc>& __x, const forward_list<_Tp, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const forward_list<_Tp, _Alloc>& __x, const forward_list<_Tp, _Alloc>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const forward_list<_Tp, _Alloc>& __x, const forward_list<_Tp, _Alloc>& __y) {
+ return __y < __x;
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const forward_list<_Tp, _Alloc>& __x, const forward_list<_Tp, _Alloc>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const forward_list<_Tp, _Alloc>& __x, const forward_list<_Tp, _Alloc>& __y) {
+ return !(__y < __x);
+}
+
+#else // #if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __synth_three_way_result<_Tp>
+operator<=>(const forward_list<_Tp, _Allocator>& __x, const forward_list<_Tp, _Allocator>& __y) {
+ return std::lexicographical_compare_three_way(
+ __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+}
+
+#endif // #if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void swap(forward_list<_Tp, _Alloc>& __x, forward_list<_Tp, _Alloc>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Allocator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename forward_list<_Tp, _Allocator>::size_type
+erase_if(forward_list<_Tp, _Allocator>& __c, _Predicate __pred) {
+ return __c.remove_if(__pred);
+}
+
+template <class _Tp, class _Allocator, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI typename forward_list<_Tp, _Allocator>::size_type
+erase(forward_list<_Tp, _Allocator>& __c, const _Up& __v) {
+ return std::erase_if(__c, [&](auto& __elem) { return __elem == __v; });
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _ValueT>
+using forward_list _LIBCPP_AVAILABILITY_PMR = std::forward_list<_ValueT, polymorphic_allocator<_ValueT>>;
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <atomic>
+# include <concepts>
+# include <cstdint>
+# include <cstdlib>
+# include <cstring>
+# include <functional>
+# include <iosfwd>
+# include <iterator>
+# include <stdexcept>
+# include <type_traits>
+# include <typeinfo>
+#endif
+
+#endif // _LIBCPP_FORWARD_LIST
diff --git a/libcxx/include/__cxx03/fstream b/libcxx/include/__cxx03/fstream
new file mode 100644
index 00000000000000..ab5ebf8e2c3d30
--- /dev/null
+++ b/libcxx/include/__cxx03/fstream
@@ -0,0 +1,1572 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_FSTREAM
+#define _LIBCPP_FSTREAM
+
+/*
+ fstream synopsis
+
+template <class charT, class traits = char_traits<charT> >
+class basic_filebuf
+ : public basic_streambuf<charT, traits>
+{
+public:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ // 27.9.1.2 Constructors/destructor:
+ basic_filebuf();
+ basic_filebuf(basic_filebuf&& rhs);
+ virtual ~basic_filebuf();
+
+ // 27.9.1.3 Assign/swap:
+ basic_filebuf& operator=(basic_filebuf&& rhs);
+ void swap(basic_filebuf& rhs);
+
+ // 27.9.1.4 Members:
+ bool is_open() const;
+ basic_filebuf* open(const char* s, ios_base::openmode mode);
+ basic_filebuf* open(const string& s, ios_base::openmode mode);
+ basic_filebuf* open(const filesystem::path& p, ios_base::openmode mode); // C++17
+ basic_filebuf* close();
+
+protected:
+ // 27.9.1.5 Overridden virtual functions:
+ virtual streamsize showmanyc();
+ virtual int_type underflow();
+ virtual int_type uflow();
+ virtual int_type pbackfail(int_type c = traits_type::eof());
+ virtual int_type overflow (int_type c = traits_type::eof());
+ virtual basic_streambuf<char_type, traits_type>* setbuf(char_type* s, streamsize n);
+ virtual pos_type seekoff(off_type off, ios_base::seekdir way,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ virtual pos_type seekpos(pos_type sp,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ virtual int sync();
+ virtual void imbue(const locale& loc);
+};
+
+template <class charT, class traits>
+ void
+ swap(basic_filebuf<charT, traits>& x, basic_filebuf<charT, traits>& y);
+
+typedef basic_filebuf<char> filebuf;
+typedef basic_filebuf<wchar_t> wfilebuf;
+
+template <class charT, class traits = char_traits<charT> >
+class basic_ifstream
+ : public basic_istream<charT,traits>
+{
+public:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26
+
+ basic_ifstream();
+ explicit basic_ifstream(const char* s, ios_base::openmode mode = ios_base::in);
+ explicit basic_ifstream(const string& s, ios_base::openmode mode = ios_base::in);
+ template<class T>
+ explicit basic_ifstream(const T& s, ios_base::openmode mode = ios_base::in); // Since C++17
+ basic_ifstream(basic_ifstream&& rhs);
+
+ basic_ifstream& operator=(basic_ifstream&& rhs);
+ void swap(basic_ifstream& rhs);
+
+ basic_filebuf<char_type, traits_type>* rdbuf() const;
+ native_handle_type native_handle() const noexcept; // Since C++26
+ bool is_open() const;
+ void open(const char* s, ios_base::openmode mode = ios_base::in);
+ void open(const string& s, ios_base::openmode mode = ios_base::in);
+ void open(const filesystem::path& s, ios_base::openmode mode = ios_base::in); // C++17
+
+ void close();
+};
+
+template <class charT, class traits>
+ void
+ swap(basic_ifstream<charT, traits>& x, basic_ifstream<charT, traits>& y);
+
+typedef basic_ifstream<char> ifstream;
+typedef basic_ifstream<wchar_t> wifstream;
+
+template <class charT, class traits = char_traits<charT> >
+class basic_ofstream
+ : public basic_ostream<charT,traits>
+{
+public:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26
+
+ basic_ofstream();
+ explicit basic_ofstream(const char* s, ios_base::openmode mode = ios_base::out);
+ explicit basic_ofstream(const string& s, ios_base::openmode mode = ios_base::out);
+ template<class T>
+ explicit basic_ofstream(const T& s, ios_base::openmode mode = ios_base::out); // Since C++17
+ basic_ofstream(basic_ofstream&& rhs);
+
+ basic_ofstream& operator=(basic_ofstream&& rhs);
+ void swap(basic_ofstream& rhs);
+
+ basic_filebuf<char_type, traits_type>* rdbuf() const;
+ native_handle_type native_handle() const noexcept; // Since C++26
+
+ bool is_open() const;
+ void open(const char* s, ios_base::openmode mode = ios_base::out);
+ void open(const string& s, ios_base::openmode mode = ios_base::out);
+ void open(const filesystem::path& p,
+ ios_base::openmode mode = ios_base::out); // C++17
+
+ void close();
+};
+
+template <class charT, class traits>
+ void
+ swap(basic_ofstream<charT, traits>& x, basic_ofstream<charT, traits>& y);
+
+typedef basic_ofstream<char> ofstream;
+typedef basic_ofstream<wchar_t> wofstream;
+
+template <class charT, class traits=char_traits<charT> >
+class basic_fstream
+ : public basic_iostream<charT,traits>
+{
+public:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26
+
+ basic_fstream();
+ explicit basic_fstream(const char* s, ios_base::openmode mode = ios_base::in|ios_base::out);
+ explicit basic_fstream(const string& s, ios_base::openmode mode = ios_base::in|ios_base::out);
+ template<class T>
+ explicit basic_fstream(const T& s, ios_base::openmode mode = ios_base::in | ios_base::out); // Since C++17
+ basic_fstream(basic_fstream&& rhs);
+
+ basic_fstream& operator=(basic_fstream&& rhs);
+ void swap(basic_fstream& rhs);
+
+ basic_filebuf<char_type, traits_type>* rdbuf() const;
+ native_handle_type native_handle() const noexcept; // Since C++26
+ bool is_open() const;
+ void open(const char* s, ios_base::openmode mode = ios_base::in|ios_base::out);
+ void open(const string& s, ios_base::openmode mode = ios_base::in|ios_base::out);
+ void open(const filesystem::path& s,
+ ios_base::openmode mode = ios_base::in|ios_base::out); // C++17
+
+ void close();
+};
+
+template <class charT, class traits>
+ void swap(basic_fstream<charT, traits>& x, basic_fstream<charT, traits>& y);
+
+typedef basic_fstream<char> fstream;
+typedef basic_fstream<wchar_t> wfstream;
+
+} // std
+
+*/
+
+#include <__algorithm/max.h>
+#include <__assert>
+#include <__config>
+#include <__fwd/fstream.h>
+#include <__locale>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_same.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <__utility/unreachable.h>
+#include <cstdio>
+#include <filesystem>
+#include <istream>
+#include <ostream>
+#include <typeinfo>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if defined(_LIBCPP_MSVCRT) || defined(_NEWLIB_VERSION)
+# define _LIBCPP_HAS_NO_OFF_T_FUNCTIONS
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_FILESYSTEM)
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_WIN32API)
+_LIBCPP_EXPORTED_FROM_ABI void* __filebuf_windows_native_handle(FILE* __file) noexcept;
+# endif
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_filebuf : public basic_streambuf<_CharT, _Traits> {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef typename traits_type::state_type state_type;
+# if _LIBCPP_STD_VER >= 26
+# if defined(_LIBCPP_WIN32API)
+ using native_handle_type = void*; // HANDLE
+# elif __has_include(<unistd.h>)
+ using native_handle_type = int; // POSIX file descriptor
+# else
+# error "Provide a native file handle!"
+# endif
+# endif
+
+ // 27.9.1.2 Constructors/destructor:
+ basic_filebuf();
+ basic_filebuf(basic_filebuf&& __rhs);
+ ~basic_filebuf() override;
+
+ // 27.9.1.3 Assign/swap:
+ _LIBCPP_HIDE_FROM_ABI basic_filebuf& operator=(basic_filebuf&& __rhs);
+ void swap(basic_filebuf& __rhs);
+
+ // 27.9.1.4 Members:
+ _LIBCPP_HIDE_FROM_ABI bool is_open() const;
+ basic_filebuf* open(const char* __s, ios_base::openmode __mode);
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+ basic_filebuf* open(const wchar_t* __s, ios_base::openmode __mode);
+# endif
+ _LIBCPP_HIDE_FROM_ABI basic_filebuf* open(const string& __s, ios_base::openmode __mode);
+
+# if _LIBCPP_STD_VER >= 17
+ _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI basic_filebuf*
+ open(const filesystem::path& __p, ios_base::openmode __mode) {
+ return open(__p.c_str(), __mode);
+ }
+# endif
+ _LIBCPP_HIDE_FROM_ABI basic_filebuf* __open(int __fd, ios_base::openmode __mode);
+ basic_filebuf* close();
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() const noexcept {
+ _LIBCPP_ASSERT_UNCATEGORIZED(this->is_open(), "File must be opened");
+# if defined(_LIBCPP_WIN32API)
+ return std::__filebuf_windows_native_handle(__file_);
+# elif __has_include(<unistd.h>)
+ return fileno(__file_);
+# else
+# error "Provide a way to determine the file native handle!"
+# endif
+ }
+# endif // _LIBCPP_STD_VER >= 26
+
+ _LIBCPP_HIDE_FROM_ABI inline static const char* __make_mdstring(ios_base::openmode __mode) _NOEXCEPT;
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+ _LIBCPP_HIDE_FROM_ABI inline static const wchar_t* __make_mdwstring(ios_base::openmode __mode) _NOEXCEPT;
+# endif
+
+protected:
+ // 27.9.1.5 Overridden virtual functions:
+ int_type underflow() override;
+ int_type pbackfail(int_type __c = traits_type::eof()) override;
+ int_type overflow(int_type __c = traits_type::eof()) override;
+ basic_streambuf<char_type, traits_type>* setbuf(char_type* __s, streamsize __n) override;
+ pos_type
+ seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __wch = ios_base::in | ios_base::out) override;
+ pos_type seekpos(pos_type __sp, ios_base::openmode __wch = ios_base::in | ios_base::out) override;
+ int sync() override;
+ void imbue(const locale& __loc) override;
+
+private:
+ char* __extbuf_;
+ const char* __extbufnext_;
+ const char* __extbufend_;
+ char __extbuf_min_[8];
+ size_t __ebs_;
+ char_type* __intbuf_;
+ size_t __ibs_;
+ FILE* __file_;
+ const codecvt<char_type, char, state_type>* __cv_;
+ state_type __st_;
+ state_type __st_last_;
+ ios_base::openmode __om_;
+ // There have been no file operations yet, which allows setting unbuffered
+ // I/O mode.
+ static const ios_base::openmode __no_io_operations = ios_base::trunc;
+ // Unbuffered I/O mode has been requested.
+ static const ios_base::openmode __use_unbuffered_io = ios_base::ate;
+ // Used to track the currently used mode and track whether the output should
+ // be unbuffered.
+ // [filebuf.virtuals]/12
+ // If setbuf(0, 0) is called on a stream before any I/O has occurred on
+ // that stream, the stream becomes unbuffered. Otherwise the results are
+ // implementation-defined.
+ // This allows calling setbuf(0, 0)
+ // - before opening a file,
+ // - after opening a file, before
+ // - a read
+ // - a write
+ // - a seek.
+ // Note that opening a file with ios_base::ate does a seek operation.
+ // Normally underflow, overflow, and sync change this flag to ios_base::in,
+ // ios_base_out, or 0.
+ //
+ // The ios_base::trunc and ios_base::ate flags are not used in __cm_. They
+ // are used to track the state of the unbuffered request. For readability
+ // they have the aliases __no_io_operations and __use_unbuffered_io
+ // respectively.
+ //
+ // The __no_io_operations and __use_unbuffered_io flags are used in the
+ // following way:
+ // - __no_io_operations is set upon construction to indicate the unbuffered
+ // state can be set.
+ // - When requesting unbuffered output:
+ // - If the file is open it sets the mode.
+ // - Else places a request by adding the __use_unbuffered_io flag.
+ // - When a file is opened it checks whether both __no_io_operations and
+ // __use_unbuffered_io are set. If so switches to unbuffered mode.
+ // - All file I/O operations change the mode effectively clearing the
+ // __no_io_operations and __use_unbuffered_io flags.
+ ios_base::openmode __cm_;
+ bool __owns_eb_;
+ bool __owns_ib_;
+ bool __always_noconv_;
+
+ bool __read_mode();
+ void __write_mode();
+
+ _LIBCPP_EXPORTED_FROM_ABI friend FILE* __get_ostream_file(ostream&);
+
+ // There are multiple (__)open function, they use different C-API open
+ // function. After that call these functions behave the same. This function
+ // does that part and determines the final return value.
+ _LIBCPP_HIDE_FROM_ABI basic_filebuf* __do_open(FILE* __file, ios_base::openmode __mode) {
+ __file_ = __file;
+ if (!__file_)
+ return nullptr;
+
+ __om_ = __mode;
+ if (__cm_ == (__no_io_operations | __use_unbuffered_io)) {
+ std::setbuf(__file_, nullptr);
+ __cm_ = 0;
+ }
+
+ if (__mode & ios_base::ate) {
+ __cm_ = 0;
+ if (fseek(__file_, 0, SEEK_END)) {
+ fclose(__file_);
+ __file_ = nullptr;
+ return nullptr;
+ }
+ }
+
+ return this;
+ }
+
+ // If the file is already open, switch to unbuffered mode. Otherwise, record
+ // the request to use unbuffered mode so that we use that mode when we
+ // eventually open the file.
+ _LIBCPP_HIDE_FROM_ABI void __request_unbuffered_mode(char_type* __s, streamsize __n) {
+ if (__cm_ == __no_io_operations && __s == nullptr && __n == 0) {
+ if (__file_) {
+ std::setbuf(__file_, nullptr);
+ __cm_ = 0;
+ } else {
+ __cm_ = __no_io_operations | __use_unbuffered_io;
+ }
+ }
+ }
+};
+
+template <class _CharT, class _Traits>
+basic_filebuf<_CharT, _Traits>::basic_filebuf()
+ : __extbuf_(nullptr),
+ __extbufnext_(nullptr),
+ __extbufend_(nullptr),
+ __ebs_(0),
+ __intbuf_(nullptr),
+ __ibs_(0),
+ __file_(nullptr),
+ __cv_(nullptr),
+ __st_(),
+ __st_last_(),
+ __om_(0),
+ __cm_(__no_io_operations),
+ __owns_eb_(false),
+ __owns_ib_(false),
+ __always_noconv_(false) {
+ if (std::has_facet<codecvt<char_type, char, state_type> >(this->getloc())) {
+ __cv_ = &std::use_facet<codecvt<char_type, char, state_type> >(this->getloc());
+ __always_noconv_ = __cv_->always_noconv();
+ }
+ setbuf(nullptr, 4096);
+}
+
+template <class _CharT, class _Traits>
+basic_filebuf<_CharT, _Traits>::basic_filebuf(basic_filebuf&& __rhs) : basic_streambuf<_CharT, _Traits>(__rhs) {
+ if (__rhs.__extbuf_ == __rhs.__extbuf_min_) {
+ __extbuf_ = __extbuf_min_;
+ __extbufnext_ = __extbuf_ + (__rhs.__extbufnext_ - __rhs.__extbuf_);
+ __extbufend_ = __extbuf_ + (__rhs.__extbufend_ - __rhs.__extbuf_);
+ } else {
+ __extbuf_ = __rhs.__extbuf_;
+ __extbufnext_ = __rhs.__extbufnext_;
+ __extbufend_ = __rhs.__extbufend_;
+ }
+ __ebs_ = __rhs.__ebs_;
+ __intbuf_ = __rhs.__intbuf_;
+ __ibs_ = __rhs.__ibs_;
+ __file_ = __rhs.__file_;
+ __cv_ = __rhs.__cv_;
+ __st_ = __rhs.__st_;
+ __st_last_ = __rhs.__st_last_;
+ __om_ = __rhs.__om_;
+ __cm_ = __rhs.__cm_;
+ __owns_eb_ = __rhs.__owns_eb_;
+ __owns_ib_ = __rhs.__owns_ib_;
+ __always_noconv_ = __rhs.__always_noconv_;
+ if (__rhs.pbase()) {
+ if (__rhs.pbase() == __rhs.__intbuf_)
+ this->setp(__intbuf_, __intbuf_ + (__rhs.epptr() - __rhs.pbase()));
+ else
+ this->setp((char_type*)__extbuf_, (char_type*)__extbuf_ + (__rhs.epptr() - __rhs.pbase()));
+ this->__pbump(__rhs.pptr() - __rhs.pbase());
+ } else if (__rhs.eback()) {
+ if (__rhs.eback() == __rhs.__intbuf_)
+ this->setg(__intbuf_, __intbuf_ + (__rhs.gptr() - __rhs.eback()), __intbuf_ + (__rhs.egptr() - __rhs.eback()));
+ else
+ this->setg((char_type*)__extbuf_,
+ (char_type*)__extbuf_ + (__rhs.gptr() - __rhs.eback()),
+ (char_type*)__extbuf_ + (__rhs.egptr() - __rhs.eback()));
+ }
+ __rhs.__extbuf_ = nullptr;
+ __rhs.__extbufnext_ = nullptr;
+ __rhs.__extbufend_ = nullptr;
+ __rhs.__ebs_ = 0;
+ __rhs.__intbuf_ = 0;
+ __rhs.__ibs_ = 0;
+ __rhs.__file_ = nullptr;
+ __rhs.__st_ = state_type();
+ __rhs.__st_last_ = state_type();
+ __rhs.__om_ = 0;
+ __rhs.__cm_ = 0;
+ __rhs.__owns_eb_ = false;
+ __rhs.__owns_ib_ = false;
+ __rhs.setg(0, 0, 0);
+ __rhs.setp(0, 0);
+}
+
+template <class _CharT, class _Traits>
+inline basic_filebuf<_CharT, _Traits>& basic_filebuf<_CharT, _Traits>::operator=(basic_filebuf&& __rhs) {
+ close();
+ swap(__rhs);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_filebuf<_CharT, _Traits>::~basic_filebuf() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ close();
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (__owns_eb_)
+ delete[] __extbuf_;
+ if (__owns_ib_)
+ delete[] __intbuf_;
+}
+
+template <class _CharT, class _Traits>
+void basic_filebuf<_CharT, _Traits>::swap(basic_filebuf& __rhs) {
+ basic_streambuf<char_type, traits_type>::swap(__rhs);
+ if (__extbuf_ != __extbuf_min_ && __rhs.__extbuf_ != __rhs.__extbuf_min_) {
+ // Neither *this nor __rhs uses the small buffer, so we can simply swap the pointers.
+ std::swap(__extbuf_, __rhs.__extbuf_);
+ std::swap(__extbufnext_, __rhs.__extbufnext_);
+ std::swap(__extbufend_, __rhs.__extbufend_);
+ } else {
+ ptrdiff_t __ln = __extbufnext_ ? __extbufnext_ - __extbuf_ : 0;
+ ptrdiff_t __le = __extbufend_ ? __extbufend_ - __extbuf_ : 0;
+ ptrdiff_t __rn = __rhs.__extbufnext_ ? __rhs.__extbufnext_ - __rhs.__extbuf_ : 0;
+ ptrdiff_t __re = __rhs.__extbufend_ ? __rhs.__extbufend_ - __rhs.__extbuf_ : 0;
+ if (__extbuf_ == __extbuf_min_ && __rhs.__extbuf_ != __rhs.__extbuf_min_) {
+ // *this uses the small buffer, but __rhs doesn't.
+ __extbuf_ = __rhs.__extbuf_;
+ __rhs.__extbuf_ = __rhs.__extbuf_min_;
+ std::memmove(__rhs.__extbuf_min_, __extbuf_min_, sizeof(__extbuf_min_));
+ } else if (__extbuf_ != __extbuf_min_ && __rhs.__extbuf_ == __rhs.__extbuf_min_) {
+ // *this doesn't use the small buffer, but __rhs does.
+ __rhs.__extbuf_ = __extbuf_;
+ __extbuf_ = __extbuf_min_;
+ std::memmove(__extbuf_min_, __rhs.__extbuf_min_, sizeof(__extbuf_min_));
+ } else {
+ // Both *this and __rhs use the small buffer.
+ char __tmp[sizeof(__extbuf_min_)];
+ std::memmove(__tmp, __extbuf_min_, sizeof(__extbuf_min_));
+ std::memmove(__extbuf_min_, __rhs.__extbuf_min_, sizeof(__extbuf_min_));
+ std::memmove(__rhs.__extbuf_min_, __tmp, sizeof(__extbuf_min_));
+ }
+ __extbufnext_ = __extbuf_ + __rn;
+ __extbufend_ = __extbuf_ + __re;
+ __rhs.__extbufnext_ = __rhs.__extbuf_ + __ln;
+ __rhs.__extbufend_ = __rhs.__extbuf_ + __le;
+ }
+ std::swap(__ebs_, __rhs.__ebs_);
+ std::swap(__intbuf_, __rhs.__intbuf_);
+ std::swap(__ibs_, __rhs.__ibs_);
+ std::swap(__file_, __rhs.__file_);
+ std::swap(__cv_, __rhs.__cv_);
+ std::swap(__st_, __rhs.__st_);
+ std::swap(__st_last_, __rhs.__st_last_);
+ std::swap(__om_, __rhs.__om_);
+ std::swap(__cm_, __rhs.__cm_);
+ std::swap(__owns_eb_, __rhs.__owns_eb_);
+ std::swap(__owns_ib_, __rhs.__owns_ib_);
+ std::swap(__always_noconv_, __rhs.__always_noconv_);
+ if (this->eback() == (char_type*)__rhs.__extbuf_min_) {
+ ptrdiff_t __n = this->gptr() - this->eback();
+ ptrdiff_t __e = this->egptr() - this->eback();
+ this->setg((char_type*)__extbuf_min_, (char_type*)__extbuf_min_ + __n, (char_type*)__extbuf_min_ + __e);
+ } else if (this->pbase() == (char_type*)__rhs.__extbuf_min_) {
+ ptrdiff_t __n = this->pptr() - this->pbase();
+ ptrdiff_t __e = this->epptr() - this->pbase();
+ this->setp((char_type*)__extbuf_min_, (char_type*)__extbuf_min_ + __e);
+ this->__pbump(__n);
+ }
+ if (__rhs.eback() == (char_type*)__extbuf_min_) {
+ ptrdiff_t __n = __rhs.gptr() - __rhs.eback();
+ ptrdiff_t __e = __rhs.egptr() - __rhs.eback();
+ __rhs.setg(
+ (char_type*)__rhs.__extbuf_min_, (char_type*)__rhs.__extbuf_min_ + __n, (char_type*)__rhs.__extbuf_min_ + __e);
+ } else if (__rhs.pbase() == (char_type*)__extbuf_min_) {
+ ptrdiff_t __n = __rhs.pptr() - __rhs.pbase();
+ ptrdiff_t __e = __rhs.epptr() - __rhs.pbase();
+ __rhs.setp((char_type*)__rhs.__extbuf_min_, (char_type*)__rhs.__extbuf_min_ + __e);
+ __rhs.__pbump(__n);
+ }
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void swap(basic_filebuf<_CharT, _Traits>& __x, basic_filebuf<_CharT, _Traits>& __y) {
+ __x.swap(__y);
+}
+
+template <class _CharT, class _Traits>
+inline bool basic_filebuf<_CharT, _Traits>::is_open() const {
+ return __file_ != nullptr;
+}
+
+template <class _CharT, class _Traits>
+const char* basic_filebuf<_CharT, _Traits>::__make_mdstring(ios_base::openmode __mode) _NOEXCEPT {
+ switch (__mode & ~ios_base::ate) {
+ case ios_base::out:
+ case ios_base::out | ios_base::trunc:
+ return "w" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::out | ios_base::app:
+ case ios_base::app:
+ return "a" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in:
+ return "r" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::out:
+ return "r+" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::out | ios_base::trunc:
+ return "w+" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::out | ios_base::app:
+ case ios_base::in | ios_base::app:
+ return "a+" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::out | ios_base::binary:
+ case ios_base::out | ios_base::trunc | ios_base::binary:
+ return "wb" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::out | ios_base::app | ios_base::binary:
+ case ios_base::app | ios_base::binary:
+ return "ab" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::binary:
+ return "rb" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::out | ios_base::binary:
+ return "r+b" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary:
+ return "w+b" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::out | ios_base::app | ios_base::binary:
+ case ios_base::in | ios_base::app | ios_base::binary:
+ return "a+b" _LIBCPP_FOPEN_CLOEXEC_MODE;
+# if _LIBCPP_STD_VER >= 23
+ case ios_base::out | ios_base::noreplace:
+ case ios_base::out | ios_base::trunc | ios_base::noreplace:
+ return "wx" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::out | ios_base::trunc | ios_base::noreplace:
+ return "w+x" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::out | ios_base::binary | ios_base::noreplace:
+ case ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
+ return "wbx" _LIBCPP_FOPEN_CLOEXEC_MODE;
+ case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
+ return "w+bx" _LIBCPP_FOPEN_CLOEXEC_MODE;
+# endif // _LIBCPP_STD_VER >= 23
+ default:
+ return nullptr;
+ }
+ __libcpp_unreachable();
+}
+
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+template <class _CharT, class _Traits>
+const wchar_t* basic_filebuf<_CharT, _Traits>::__make_mdwstring(ios_base::openmode __mode) _NOEXCEPT {
+ switch (__mode & ~ios_base::ate) {
+ case ios_base::out:
+ case ios_base::out | ios_base::trunc:
+ return L"w";
+ case ios_base::out | ios_base::app:
+ case ios_base::app:
+ return L"a";
+ case ios_base::in:
+ return L"r";
+ case ios_base::in | ios_base::out:
+ return L"r+";
+ case ios_base::in | ios_base::out | ios_base::trunc:
+ return L"w+";
+ case ios_base::in | ios_base::out | ios_base::app:
+ case ios_base::in | ios_base::app:
+ return L"a+";
+ case ios_base::out | ios_base::binary:
+ case ios_base::out | ios_base::trunc | ios_base::binary:
+ return L"wb";
+ case ios_base::out | ios_base::app | ios_base::binary:
+ case ios_base::app | ios_base::binary:
+ return L"ab";
+ case ios_base::in | ios_base::binary:
+ return L"rb";
+ case ios_base::in | ios_base::out | ios_base::binary:
+ return L"r+b";
+ case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary:
+ return L"w+b";
+ case ios_base::in | ios_base::out | ios_base::app | ios_base::binary:
+ case ios_base::in | ios_base::app | ios_base::binary:
+ return L"a+b";
+# if _LIBCPP_STD_VER >= 23
+ case ios_base::out | ios_base::noreplace:
+ case ios_base::out | ios_base::trunc | ios_base::noreplace:
+ return L"wx";
+ case ios_base::in | ios_base::out | ios_base::trunc | ios_base::noreplace:
+ return L"w+x";
+ case ios_base::out | ios_base::binary | ios_base::noreplace:
+ case ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
+ return L"wbx";
+ case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
+ return L"w+bx";
+# endif // _LIBCPP_STD_VER >= 23
+ default:
+ return nullptr;
+ }
+ __libcpp_unreachable();
+}
+# endif
+
+template <class _CharT, class _Traits>
+basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) {
+ if (__file_)
+ return nullptr;
+ const char* __mdstr = __make_mdstring(__mode);
+ if (!__mdstr)
+ return nullptr;
+
+ return __do_open(fopen(__s, __mdstr), __mode);
+}
+
+template <class _CharT, class _Traits>
+inline basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) {
+ if (__file_)
+ return nullptr;
+ const char* __mdstr = __make_mdstring(__mode);
+ if (!__mdstr)
+ return nullptr;
+
+ return __do_open(fdopen(__fd, __mdstr), __mode);
+}
+
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+// This is basically the same as the char* overload except that it uses _wfopen
+// and long mode strings.
+template <class _CharT, class _Traits>
+basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
+ if (__file_)
+ return nullptr;
+ const wchar_t* __mdstr = __make_mdwstring(__mode);
+ if (!__mdstr)
+ return nullptr;
+
+ return __do_open(_wfopen(__s, __mdstr), __mode);
+}
+# endif
+
+template <class _CharT, class _Traits>
+inline basic_filebuf<_CharT, _Traits>*
+basic_filebuf<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) {
+ return open(__s.c_str(), __mode);
+}
+
+template <class _CharT, class _Traits>
+basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::close() {
+ basic_filebuf<_CharT, _Traits>* __rt = nullptr;
+ if (__file_) {
+ __rt = this;
+ unique_ptr<FILE, int (*)(FILE*)> __h(__file_, fclose);
+ if (sync())
+ __rt = nullptr;
+ if (fclose(__h.release()))
+ __rt = nullptr;
+ __file_ = nullptr;
+ setbuf(0, 0);
+ }
+ return __rt;
+}
+
+template <class _CharT, class _Traits>
+typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::underflow() {
+ if (__file_ == nullptr)
+ return traits_type::eof();
+ bool __initial = __read_mode();
+ char_type __1buf;
+ if (this->gptr() == nullptr)
+ this->setg(&__1buf, &__1buf + 1, &__1buf + 1);
+ const size_t __unget_sz = __initial ? 0 : std::min<size_t>((this->egptr() - this->eback()) / 2, 4);
+ int_type __c = traits_type::eof();
+ if (this->gptr() == this->egptr()) {
+ std::memmove(this->eback(), this->egptr() - __unget_sz, __unget_sz * sizeof(char_type));
+ if (__always_noconv_) {
+ size_t __nmemb = static_cast<size_t>(this->egptr() - this->eback() - __unget_sz);
+ __nmemb = ::fread(this->eback() + __unget_sz, 1, __nmemb, __file_);
+ if (__nmemb != 0) {
+ this->setg(this->eback(), this->eback() + __unget_sz, this->eback() + __unget_sz + __nmemb);
+ __c = traits_type::to_int_type(*this->gptr());
+ }
+ } else {
+ if (__extbufend_ != __extbufnext_) {
+ _LIBCPP_ASSERT_NON_NULL(__extbufnext_ != nullptr, "underflow moving from nullptr");
+ _LIBCPP_ASSERT_NON_NULL(__extbuf_ != nullptr, "underflow moving into nullptr");
+ std::memmove(__extbuf_, __extbufnext_, __extbufend_ - __extbufnext_);
+ }
+ __extbufnext_ = __extbuf_ + (__extbufend_ - __extbufnext_);
+ __extbufend_ = __extbuf_ + (__extbuf_ == __extbuf_min_ ? sizeof(__extbuf_min_) : __ebs_);
+ size_t __nmemb =
+ std::min(static_cast<size_t>(__ibs_ - __unget_sz), static_cast<size_t>(__extbufend_ - __extbufnext_));
+ codecvt_base::result __r;
+ __st_last_ = __st_;
+ size_t __nr = fread((void*)const_cast<char*>(__extbufnext_), 1, __nmemb, __file_);
+ if (__nr != 0) {
+ if (!__cv_)
+ __throw_bad_cast();
+
+ __extbufend_ = __extbufnext_ + __nr;
+ char_type* __inext;
+ __r = __cv_->in(
+ __st_, __extbuf_, __extbufend_, __extbufnext_, this->eback() + __unget_sz, this->eback() + __ibs_, __inext);
+ if (__r == codecvt_base::noconv) {
+ this->setg((char_type*)__extbuf_, (char_type*)__extbuf_, (char_type*)const_cast<char*>(__extbufend_));
+ __c = traits_type::to_int_type(*this->gptr());
+ } else if (__inext != this->eback() + __unget_sz) {
+ this->setg(this->eback(), this->eback() + __unget_sz, __inext);
+ __c = traits_type::to_int_type(*this->gptr());
+ }
+ }
+ }
+ } else
+ __c = traits_type::to_int_type(*this->gptr());
+ if (this->eback() == &__1buf)
+ this->setg(nullptr, nullptr, nullptr);
+ return __c;
+}
+
+template <class _CharT, class _Traits>
+typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::pbackfail(int_type __c) {
+ if (__file_ && this->eback() < this->gptr()) {
+ if (traits_type::eq_int_type(__c, traits_type::eof())) {
+ this->gbump(-1);
+ return traits_type::not_eof(__c);
+ }
+ if ((__om_ & ios_base::out) || traits_type::eq(traits_type::to_char_type(__c), this->gptr()[-1])) {
+ this->gbump(-1);
+ *this->gptr() = traits_type::to_char_type(__c);
+ return __c;
+ }
+ }
+ return traits_type::eof();
+}
+
+template <class _CharT, class _Traits>
+typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::overflow(int_type __c) {
+ if (__file_ == nullptr)
+ return traits_type::eof();
+ __write_mode();
+ char_type __1buf;
+ char_type* __pb_save = this->pbase();
+ char_type* __epb_save = this->epptr();
+ if (!traits_type::eq_int_type(__c, traits_type::eof())) {
+ if (this->pptr() == nullptr)
+ this->setp(&__1buf, &__1buf + 1);
+ *this->pptr() = traits_type::to_char_type(__c);
+ this->pbump(1);
+ }
+ if (this->pptr() != this->pbase()) {
+ if (__always_noconv_) {
+ size_t __nmemb = static_cast<size_t>(this->pptr() - this->pbase());
+ if (std::fwrite(this->pbase(), sizeof(char_type), __nmemb, __file_) != __nmemb)
+ return traits_type::eof();
+ } else {
+ char* __extbe = __extbuf_;
+ codecvt_base::result __r;
+ do {
+ if (!__cv_)
+ __throw_bad_cast();
+
+ const char_type* __e;
+ __r = __cv_->out(__st_, this->pbase(), this->pptr(), __e, __extbuf_, __extbuf_ + __ebs_, __extbe);
+ if (__e == this->pbase())
+ return traits_type::eof();
+ if (__r == codecvt_base::noconv) {
+ size_t __nmemb = static_cast<size_t>(this->pptr() - this->pbase());
+ if (std::fwrite(this->pbase(), 1, __nmemb, __file_) != __nmemb)
+ return traits_type::eof();
+ } else if (__r == codecvt_base::ok || __r == codecvt_base::partial) {
+ size_t __nmemb = static_cast<size_t>(__extbe - __extbuf_);
+ if (fwrite(__extbuf_, 1, __nmemb, __file_) != __nmemb)
+ return traits_type::eof();
+ if (__r == codecvt_base::partial) {
+ this->setp(const_cast<char_type*>(__e), this->pptr());
+ this->__pbump(this->epptr() - this->pbase());
+ }
+ } else
+ return traits_type::eof();
+ } while (__r == codecvt_base::partial);
+ }
+ this->setp(__pb_save, __epb_save);
+ }
+ return traits_type::not_eof(__c);
+}
+
+template <class _CharT, class _Traits>
+basic_streambuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::setbuf(char_type* __s, streamsize __n) {
+ this->setg(nullptr, nullptr, nullptr);
+ this->setp(nullptr, nullptr);
+ __request_unbuffered_mode(__s, __n);
+ if (__owns_eb_)
+ delete[] __extbuf_;
+ if (__owns_ib_)
+ delete[] __intbuf_;
+ __ebs_ = __n;
+ if (__ebs_ > sizeof(__extbuf_min_)) {
+ if (__always_noconv_ && __s) {
+ __extbuf_ = (char*)__s;
+ __owns_eb_ = false;
+ } else {
+ __extbuf_ = new char[__ebs_];
+ __owns_eb_ = true;
+ }
+ } else {
+ __extbuf_ = __extbuf_min_;
+ __ebs_ = sizeof(__extbuf_min_);
+ __owns_eb_ = false;
+ }
+ if (!__always_noconv_) {
+ __ibs_ = max<streamsize>(__n, sizeof(__extbuf_min_));
+ if (__s && __ibs_ > sizeof(__extbuf_min_)) {
+ __intbuf_ = __s;
+ __owns_ib_ = false;
+ } else {
+ __intbuf_ = new char_type[__ibs_];
+ __owns_ib_ = true;
+ }
+ } else {
+ __ibs_ = 0;
+ __intbuf_ = nullptr;
+ __owns_ib_ = false;
+ }
+ return this;
+}
+
+template <class _CharT, class _Traits>
+typename basic_filebuf<_CharT, _Traits>::pos_type
+basic_filebuf<_CharT, _Traits>::seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode) {
+ if (!__cv_)
+ __throw_bad_cast();
+
+ int __width = __cv_->encoding();
+ if (__file_ == nullptr || (__width <= 0 && __off != 0) || sync())
+ return pos_type(off_type(-1));
+ // __width > 0 || __off == 0
+ int __whence;
+ switch (__way) {
+ case ios_base::beg:
+ __whence = SEEK_SET;
+ break;
+ case ios_base::cur:
+ __whence = SEEK_CUR;
+ break;
+ case ios_base::end:
+ __whence = SEEK_END;
+ break;
+ default:
+ return pos_type(off_type(-1));
+ }
+# if defined(_LIBCPP_HAS_NO_OFF_T_FUNCTIONS)
+ if (fseek(__file_, __width > 0 ? __width * __off : 0, __whence))
+ return pos_type(off_type(-1));
+ pos_type __r = ftell(__file_);
+# else
+ if (::fseeko(__file_, __width > 0 ? __width * __off : 0, __whence))
+ return pos_type(off_type(-1));
+ pos_type __r = ftello(__file_);
+# endif
+ __r.state(__st_);
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+typename basic_filebuf<_CharT, _Traits>::pos_type
+basic_filebuf<_CharT, _Traits>::seekpos(pos_type __sp, ios_base::openmode) {
+ if (__file_ == nullptr || sync())
+ return pos_type(off_type(-1));
+# if defined(_LIBCPP_HAS_NO_OFF_T_FUNCTIONS)
+ if (fseek(__file_, __sp, SEEK_SET))
+ return pos_type(off_type(-1));
+# else
+ if (::fseeko(__file_, __sp, SEEK_SET))
+ return pos_type(off_type(-1));
+# endif
+ __st_ = __sp.state();
+ return __sp;
+}
+
+template <class _CharT, class _Traits>
+int basic_filebuf<_CharT, _Traits>::sync() {
+ if (__file_ == nullptr)
+ return 0;
+ if (!__cv_)
+ __throw_bad_cast();
+
+ if (__cm_ & ios_base::out) {
+ if (this->pptr() != this->pbase())
+ if (overflow() == traits_type::eof())
+ return -1;
+ codecvt_base::result __r;
+ do {
+ char* __extbe;
+ __r = __cv_->unshift(__st_, __extbuf_, __extbuf_ + __ebs_, __extbe);
+ size_t __nmemb = static_cast<size_t>(__extbe - __extbuf_);
+ if (fwrite(__extbuf_, 1, __nmemb, __file_) != __nmemb)
+ return -1;
+ } while (__r == codecvt_base::partial);
+ if (__r == codecvt_base::error)
+ return -1;
+ if (fflush(__file_))
+ return -1;
+ } else if (__cm_ & ios_base::in) {
+ off_type __c;
+ state_type __state = __st_last_;
+ bool __update_st = false;
+ if (__always_noconv_)
+ __c = this->egptr() - this->gptr();
+ else {
+ int __width = __cv_->encoding();
+ __c = __extbufend_ - __extbufnext_;
+ if (__width > 0)
+ __c += __width * (this->egptr() - this->gptr());
+ else {
+ if (this->gptr() != this->egptr()) {
+ const int __off = __cv_->length(__state, __extbuf_, __extbufnext_, this->gptr() - this->eback());
+ __c += __extbufnext_ - __extbuf_ - __off;
+ __update_st = true;
+ }
+ }
+ }
+# if defined(_LIBCPP_HAS_NO_OFF_T_FUNCTIONS)
+ if (fseek(__file_, -__c, SEEK_CUR))
+ return -1;
+# else
+ if (::fseeko(__file_, -__c, SEEK_CUR))
+ return -1;
+# endif
+ if (__update_st)
+ __st_ = __state;
+ __extbufnext_ = __extbufend_ = __extbuf_;
+ this->setg(nullptr, nullptr, nullptr);
+ __cm_ = 0;
+ }
+ return 0;
+}
+
+template <class _CharT, class _Traits>
+void basic_filebuf<_CharT, _Traits>::imbue(const locale& __loc) {
+ sync();
+ __cv_ = &std::use_facet<codecvt<char_type, char, state_type> >(__loc);
+ bool __old_anc = __always_noconv_;
+ __always_noconv_ = __cv_->always_noconv();
+ if (__old_anc != __always_noconv_) {
+ this->setg(nullptr, nullptr, nullptr);
+ this->setp(nullptr, nullptr);
+ // invariant, char_type is char, else we couldn't get here
+ if (__always_noconv_) // need to dump __intbuf_
+ {
+ if (__owns_eb_)
+ delete[] __extbuf_;
+ __owns_eb_ = __owns_ib_;
+ __ebs_ = __ibs_;
+ __extbuf_ = (char*)__intbuf_;
+ __ibs_ = 0;
+ __intbuf_ = nullptr;
+ __owns_ib_ = false;
+ } else // need to obtain an __intbuf_.
+ { // If __extbuf_ is user-supplied, use it, else new __intbuf_
+ if (!__owns_eb_ && __extbuf_ != __extbuf_min_) {
+ __ibs_ = __ebs_;
+ __intbuf_ = (char_type*)__extbuf_;
+ __owns_ib_ = false;
+ __extbuf_ = new char[__ebs_];
+ __owns_eb_ = true;
+ } else {
+ __ibs_ = __ebs_;
+ __intbuf_ = new char_type[__ibs_];
+ __owns_ib_ = true;
+ }
+ }
+ }
+}
+
+template <class _CharT, class _Traits>
+bool basic_filebuf<_CharT, _Traits>::__read_mode() {
+ if (!(__cm_ & ios_base::in)) {
+ this->setp(nullptr, nullptr);
+ if (__always_noconv_)
+ this->setg((char_type*)__extbuf_, (char_type*)__extbuf_ + __ebs_, (char_type*)__extbuf_ + __ebs_);
+ else
+ this->setg(__intbuf_, __intbuf_ + __ibs_, __intbuf_ + __ibs_);
+ __cm_ = ios_base::in;
+ return true;
+ }
+ return false;
+}
+
+template <class _CharT, class _Traits>
+void basic_filebuf<_CharT, _Traits>::__write_mode() {
+ if (!(__cm_ & ios_base::out)) {
+ this->setg(nullptr, nullptr, nullptr);
+ if (__ebs_ > sizeof(__extbuf_min_)) {
+ if (__always_noconv_)
+ this->setp((char_type*)__extbuf_, (char_type*)__extbuf_ + (__ebs_ - 1));
+ else
+ this->setp(__intbuf_, __intbuf_ + (__ibs_ - 1));
+ } else
+ this->setp(nullptr, nullptr);
+ __cm_ = ios_base::out;
+ }
+}
+
+// basic_ifstream
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_ifstream : public basic_istream<_CharT, _Traits> {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+# if _LIBCPP_STD_VER >= 26
+ using native_handle_type = typename basic_filebuf<_CharT, _Traits>::native_handle_type;
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI basic_ifstream();
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ifstream(const char* __s, ios_base::openmode __mode = ios_base::in);
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ifstream(const wchar_t* __s, ios_base::openmode __mode = ios_base::in);
+# endif
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ifstream(const string& __s, ios_base::openmode __mode = ios_base::in);
+# if _LIBCPP_STD_VER >= 17
+ template <class _Tp, class = enable_if_t<is_same_v<_Tp, filesystem::path>>>
+ _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ifstream(const _Tp& __p, ios_base::openmode __mode = ios_base::in)
+ : basic_ifstream(__p.c_str(), __mode) {}
+# endif // _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI basic_ifstream(basic_ifstream&& __rhs);
+ _LIBCPP_HIDE_FROM_ABI basic_ifstream& operator=(basic_ifstream&& __rhs);
+ _LIBCPP_HIDE_FROM_ABI void swap(basic_ifstream& __rhs);
+
+ _LIBCPP_HIDE_FROM_ABI basic_filebuf<char_type, traits_type>* rdbuf() const;
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() const noexcept { return rdbuf()->native_handle(); }
+# endif
+ _LIBCPP_HIDE_FROM_ABI bool is_open() const;
+ void open(const char* __s, ios_base::openmode __mode = ios_base::in);
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+ void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::in);
+# endif
+ void open(const string& __s, ios_base::openmode __mode = ios_base::in);
+# if _LIBCPP_STD_VER >= 17
+ _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI void
+ open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in) {
+ return open(__p.c_str(), __mode);
+ }
+# endif // _LIBCPP_STD_VER >= 17
+
+ _LIBCPP_HIDE_FROM_ABI void __open(int __fd, ios_base::openmode __mode);
+ _LIBCPP_HIDE_FROM_ABI void close();
+
+private:
+ basic_filebuf<char_type, traits_type> __sb_;
+};
+
+template <class _CharT, class _Traits>
+inline basic_ifstream<_CharT, _Traits>::basic_ifstream() : basic_istream<char_type, traits_type>(&__sb_) {}
+
+template <class _CharT, class _Traits>
+inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const char* __s, ios_base::openmode __mode)
+ : basic_istream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode | ios_base::in) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+template <class _CharT, class _Traits>
+inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const wchar_t* __s, ios_base::openmode __mode)
+ : basic_istream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode | ios_base::in) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+# endif
+
+template <class _CharT, class _Traits>
+inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const string& __s, ios_base::openmode __mode)
+ : basic_istream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode | ios_base::in) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+inline basic_ifstream<_CharT, _Traits>::basic_ifstream(basic_ifstream&& __rhs)
+ : basic_istream<char_type, traits_type>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
+ this->set_rdbuf(&__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline basic_ifstream<_CharT, _Traits>& basic_ifstream<_CharT, _Traits>::operator=(basic_ifstream&& __rhs) {
+ basic_istream<char_type, traits_type>::operator=(std::move(__rhs));
+ __sb_ = std::move(__rhs.__sb_);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+inline void basic_ifstream<_CharT, _Traits>::swap(basic_ifstream& __rhs) {
+ basic_istream<char_type, traits_type>::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void swap(basic_ifstream<_CharT, _Traits>& __x, basic_ifstream<_CharT, _Traits>& __y) {
+ __x.swap(__y);
+}
+
+template <class _CharT, class _Traits>
+inline basic_filebuf<_CharT, _Traits>* basic_ifstream<_CharT, _Traits>::rdbuf() const {
+ return const_cast<basic_filebuf<char_type, traits_type>*>(&__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline bool basic_ifstream<_CharT, _Traits>::is_open() const {
+ return __sb_.is_open();
+}
+
+template <class _CharT, class _Traits>
+void basic_ifstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode | ios_base::in))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+template <class _CharT, class _Traits>
+void basic_ifstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode | ios_base::in))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+# endif
+
+template <class _CharT, class _Traits>
+void basic_ifstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode | ios_base::in))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+inline void basic_ifstream<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) {
+ if (__sb_.__open(__fd, __mode | ios_base::in))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+inline void basic_ifstream<_CharT, _Traits>::close() {
+ if (__sb_.close() == 0)
+ this->setstate(ios_base::failbit);
+}
+
+// basic_ofstream
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_ofstream : public basic_ostream<_CharT, _Traits> {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+# if _LIBCPP_STD_VER >= 26
+ using native_handle_type = typename basic_filebuf<_CharT, _Traits>::native_handle_type;
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI basic_ofstream();
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ofstream(const char* __s, ios_base::openmode __mode = ios_base::out);
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ofstream(const wchar_t* __s, ios_base::openmode __mode = ios_base::out);
+# endif
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ofstream(const string& __s, ios_base::openmode __mode = ios_base::out);
+
+# if _LIBCPP_STD_VER >= 17
+ template <class _Tp, class = enable_if_t<is_same_v<_Tp, filesystem::path>>>
+ _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ofstream(const _Tp& __p, ios_base::openmode __mode = ios_base::out)
+ : basic_ofstream(__p.c_str(), __mode) {}
+# endif // _LIBCPP_STD_VER >= 17
+
+ _LIBCPP_HIDE_FROM_ABI basic_ofstream(basic_ofstream&& __rhs);
+ _LIBCPP_HIDE_FROM_ABI basic_ofstream& operator=(basic_ofstream&& __rhs);
+ _LIBCPP_HIDE_FROM_ABI void swap(basic_ofstream& __rhs);
+
+ _LIBCPP_HIDE_FROM_ABI basic_filebuf<char_type, traits_type>* rdbuf() const;
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() const noexcept { return rdbuf()->native_handle(); }
+# endif
+ _LIBCPP_HIDE_FROM_ABI bool is_open() const;
+ void open(const char* __s, ios_base::openmode __mode = ios_base::out);
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+ void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::out);
+# endif
+ void open(const string& __s, ios_base::openmode __mode = ios_base::out);
+
+# if _LIBCPP_STD_VER >= 17
+ _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI void
+ open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::out) {
+ return open(__p.c_str(), __mode);
+ }
+# endif // _LIBCPP_STD_VER >= 17
+
+ _LIBCPP_HIDE_FROM_ABI void __open(int __fd, ios_base::openmode __mode);
+ _LIBCPP_HIDE_FROM_ABI void close();
+
+private:
+ basic_filebuf<char_type, traits_type> __sb_;
+};
+
+template <class _CharT, class _Traits>
+inline basic_ofstream<_CharT, _Traits>::basic_ofstream() : basic_ostream<char_type, traits_type>(&__sb_) {}
+
+template <class _CharT, class _Traits>
+inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const char* __s, ios_base::openmode __mode)
+ : basic_ostream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode | ios_base::out) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+template <class _CharT, class _Traits>
+inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const wchar_t* __s, ios_base::openmode __mode)
+ : basic_ostream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode | ios_base::out) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+# endif
+
+template <class _CharT, class _Traits>
+inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const string& __s, ios_base::openmode __mode)
+ : basic_ostream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode | ios_base::out) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+inline basic_ofstream<_CharT, _Traits>::basic_ofstream(basic_ofstream&& __rhs)
+ : basic_ostream<char_type, traits_type>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
+ this->set_rdbuf(&__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline basic_ofstream<_CharT, _Traits>& basic_ofstream<_CharT, _Traits>::operator=(basic_ofstream&& __rhs) {
+ basic_ostream<char_type, traits_type>::operator=(std::move(__rhs));
+ __sb_ = std::move(__rhs.__sb_);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+inline void basic_ofstream<_CharT, _Traits>::swap(basic_ofstream& __rhs) {
+ basic_ostream<char_type, traits_type>::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void swap(basic_ofstream<_CharT, _Traits>& __x, basic_ofstream<_CharT, _Traits>& __y) {
+ __x.swap(__y);
+}
+
+template <class _CharT, class _Traits>
+inline basic_filebuf<_CharT, _Traits>* basic_ofstream<_CharT, _Traits>::rdbuf() const {
+ return const_cast<basic_filebuf<char_type, traits_type>*>(&__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline bool basic_ofstream<_CharT, _Traits>::is_open() const {
+ return __sb_.is_open();
+}
+
+template <class _CharT, class _Traits>
+void basic_ofstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode | ios_base::out))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+template <class _CharT, class _Traits>
+void basic_ofstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode | ios_base::out))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+# endif
+
+template <class _CharT, class _Traits>
+void basic_ofstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode | ios_base::out))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+inline void basic_ofstream<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) {
+ if (__sb_.__open(__fd, __mode | ios_base::out))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+inline void basic_ofstream<_CharT, _Traits>::close() {
+ if (__sb_.close() == nullptr)
+ this->setstate(ios_base::failbit);
+}
+
+// basic_fstream
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_fstream : public basic_iostream<_CharT, _Traits> {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+# if _LIBCPP_STD_VER >= 26
+ using native_handle_type = typename basic_filebuf<_CharT, _Traits>::native_handle_type;
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI basic_fstream();
+ _LIBCPP_HIDE_FROM_ABI explicit basic_fstream(const char* __s,
+ ios_base::openmode __mode = ios_base::in | ios_base::out);
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+ _LIBCPP_HIDE_FROM_ABI explicit basic_fstream(const wchar_t* __s,
+ ios_base::openmode __mode = ios_base::in | ios_base::out);
+# endif
+ _LIBCPP_HIDE_FROM_ABI explicit basic_fstream(const string& __s,
+ ios_base::openmode __mode = ios_base::in | ios_base::out);
+
+# if _LIBCPP_STD_VER >= 17
+ template <class _Tp, class = enable_if_t<is_same_v<_Tp, filesystem::path>>>
+ _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI explicit basic_fstream(
+ const _Tp& __p, ios_base::openmode __mode = ios_base::in | ios_base::out)
+ : basic_fstream(__p.c_str(), __mode) {}
+# endif // _LIBCPP_STD_VER >= 17
+
+ _LIBCPP_HIDE_FROM_ABI basic_fstream(basic_fstream&& __rhs);
+
+ _LIBCPP_HIDE_FROM_ABI basic_fstream& operator=(basic_fstream&& __rhs);
+
+ _LIBCPP_HIDE_FROM_ABI void swap(basic_fstream& __rhs);
+
+ _LIBCPP_HIDE_FROM_ABI basic_filebuf<char_type, traits_type>* rdbuf() const;
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() const noexcept { return rdbuf()->native_handle(); }
+# endif
+ _LIBCPP_HIDE_FROM_ABI bool is_open() const;
+ _LIBCPP_HIDE_FROM_ABI void open(const char* __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+ void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
+# endif
+ _LIBCPP_HIDE_FROM_ABI void open(const string& __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
+
+# if _LIBCPP_STD_VER >= 17
+ _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI void
+ open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in | ios_base::out) {
+ return open(__p.c_str(), __mode);
+ }
+# endif // _LIBCPP_STD_VER >= 17
+
+ _LIBCPP_HIDE_FROM_ABI void close();
+
+private:
+ basic_filebuf<char_type, traits_type> __sb_;
+};
+
+template <class _CharT, class _Traits>
+inline basic_fstream<_CharT, _Traits>::basic_fstream() : basic_iostream<char_type, traits_type>(&__sb_) {}
+
+template <class _CharT, class _Traits>
+inline basic_fstream<_CharT, _Traits>::basic_fstream(const char* __s, ios_base::openmode __mode)
+ : basic_iostream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+template <class _CharT, class _Traits>
+inline basic_fstream<_CharT, _Traits>::basic_fstream(const wchar_t* __s, ios_base::openmode __mode)
+ : basic_iostream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+# endif
+
+template <class _CharT, class _Traits>
+inline basic_fstream<_CharT, _Traits>::basic_fstream(const string& __s, ios_base::openmode __mode)
+ : basic_iostream<char_type, traits_type>(&__sb_) {
+ if (__sb_.open(__s, __mode) == nullptr)
+ this->setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+inline basic_fstream<_CharT, _Traits>::basic_fstream(basic_fstream&& __rhs)
+ : basic_iostream<char_type, traits_type>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
+ this->set_rdbuf(&__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline basic_fstream<_CharT, _Traits>& basic_fstream<_CharT, _Traits>::operator=(basic_fstream&& __rhs) {
+ basic_iostream<char_type, traits_type>::operator=(std::move(__rhs));
+ __sb_ = std::move(__rhs.__sb_);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+inline void basic_fstream<_CharT, _Traits>::swap(basic_fstream& __rhs) {
+ basic_iostream<char_type, traits_type>::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void swap(basic_fstream<_CharT, _Traits>& __x, basic_fstream<_CharT, _Traits>& __y) {
+ __x.swap(__y);
+}
+
+template <class _CharT, class _Traits>
+inline basic_filebuf<_CharT, _Traits>* basic_fstream<_CharT, _Traits>::rdbuf() const {
+ return const_cast<basic_filebuf<char_type, traits_type>*>(&__sb_);
+}
+
+template <class _CharT, class _Traits>
+inline bool basic_fstream<_CharT, _Traits>::is_open() const {
+ return __sb_.is_open();
+}
+
+template <class _CharT, class _Traits>
+void basic_fstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+
+# ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
+template <class _CharT, class _Traits>
+void basic_fstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+# endif
+
+template <class _CharT, class _Traits>
+void basic_fstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) {
+ if (__sb_.open(__s, __mode))
+ this->clear();
+ else
+ this->setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+inline void basic_fstream<_CharT, _Traits>::close() {
+ if (__sb_.close() == nullptr)
+ this->setstate(ios_base::failbit);
+}
+
+# if _LIBCPP_AVAILABILITY_HAS_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ifstream<char>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ofstream<char>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_filebuf<char>;
+# endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_HAS_NO_FILESYSTEM
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstdlib>
+# include <iosfwd>
+# include <limits>
+# include <mutex>
+# include <new>
+# include <stdexcept>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_FSTREAM
diff --git a/libcxx/include/__cxx03/functional b/libcxx/include/__cxx03/functional
new file mode 100644
index 00000000000000..3d39f654ddb08a
--- /dev/null
+++ b/libcxx/include/__cxx03/functional
@@ -0,0 +1,598 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_FUNCTIONAL
+#define _LIBCPP_FUNCTIONAL
+
+/*
+ functional synopsis
+
+namespace std
+{
+
+template <class Arg, class Result>
+struct unary_function
+{
+ typedef Arg argument_type;
+ typedef Result result_type;
+};
+
+template <class Arg1, class Arg2, class Result>
+struct binary_function
+{
+ typedef Arg1 first_argument_type;
+ typedef Arg2 second_argument_type;
+ typedef Result result_type;
+};
+
+template <class T>
+class reference_wrapper
+ : public unary_function<T1, R> // if wrapping a unary functor
+ : public binary_function<T1, T2, R> // if wrapping a binary functor
+{
+public:
+ // types
+ typedef T type;
+ typedef see below result_type; // Not always defined
+
+ // construct/copy/destroy
+ template<class U>
+ constexpr reference_wrapper(U&&); // constexpr since C++20
+ constexpr reference_wrapper(const reference_wrapper<T>& x) noexcept; // constexpr since C++20
+
+ // assignment
+ constexpr reference_wrapper&
+ operator=(const reference_wrapper<T>& x) noexcept; // constexpr since C++20
+
+ // access
+ constexpr operator T& () const noexcept; // constexpr since C++20
+ constexpr T& get() const noexcept; // constexpr since C++20
+
+ // invoke
+ template <class... ArgTypes>
+ constexpr typename result_of<T&(ArgTypes&&...)>::type // constexpr since C++20
+ operator() (ArgTypes&&...) const
+ noexcept(is_nothrow_invocable_v<T&, ArgTypes...>); // noexcept since C++17
+};
+
+template <class T>
+ reference_wrapper(T&) -> reference_wrapper<T>;
+
+template <class T> reference_wrapper<T> ref(T& t) noexcept;
+template <class T> void ref(const T&& t) = delete;
+template <class T> reference_wrapper<T> ref(reference_wrapper<T>t) noexcept;
+
+template <class T> reference_wrapper<const T> cref(const T& t) noexcept;
+template <class T> void cref(const T&& t) = delete;
+template <class T> reference_wrapper<const T> cref(reference_wrapper<T> t) noexcept;
+
+template <class T> struct unwrap_reference; // since C++20
+template <class T> struct unwrap_ref_decay : unwrap_reference<decay_t<T>> { }; // since C++20
+template <class T> using unwrap_reference_t = typename unwrap_reference<T>::type; // since C++20
+template <class T> using unwrap_ref_decay_t = typename unwrap_ref_decay<T>::type; // since C++20
+
+// [refwrap.comparisons], comparisons
+friend constexpr bool operator==(reference_wrapper, reference_wrapper); // Since C++26
+friend constexpr bool operator==(reference_wrapper, const T&); // Since C++26
+friend constexpr bool operator==(reference_wrapper, reference_wrapper<const T>); // Since C++26
+
+friend constexpr auto operator<=>(reference_wrapper, reference_wrapper); // Since C++26
+friend constexpr auto operator<=>(reference_wrapper, const T&); // Since C++26
+friend constexpr auto operator<=>(reference_wrapper, reference_wrapper<const T>); // Since C++26
+
+template <class T> // <class T=void> in C++14
+struct plus {
+ T operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct minus {
+ T operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct multiplies {
+ T operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct divides {
+ T operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct modulus {
+ T operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct negate {
+ T operator()(const T& x) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct equal_to {
+ bool operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct not_equal_to {
+ bool operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct greater {
+ bool operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct less {
+ bool operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct greater_equal {
+ bool operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct less_equal {
+ bool operator()(const T& x, const T& y) const;
+};
+
+// [comparisons.three.way], class compare_three_way
+struct compare_three_way;
+
+template <class T> // <class T=void> in C++14
+struct logical_and {
+ bool operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct logical_or {
+ bool operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct logical_not {
+ bool operator()(const T& x) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct bit_and {
+ T operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct bit_or {
+ T operator()(const T& x, const T& y) const;
+};
+
+template <class T> // <class T=void> in C++14
+struct bit_xor {
+ T operator()(const T& x, const T& y) const;
+};
+
+template <class T=void> // C++14
+struct bit_not {
+ T operator()(const T& x) const;
+};
+
+struct identity; // C++20
+
+template <class Predicate>
+class unary_negate // deprecated in C++17, removed in C++20
+ : public unary_function<typename Predicate::argument_type, bool>
+{
+public:
+ explicit unary_negate(const Predicate& pred);
+ bool operator()(const typename Predicate::argument_type& x) const;
+};
+
+template <class Predicate> // deprecated in C++17, removed in C++20
+unary_negate<Predicate> not1(const Predicate& pred);
+
+template <class Predicate>
+class binary_negate // deprecated in C++17, removed in C++20
+ : public binary_function<typename Predicate::first_argument_type,
+ typename Predicate::second_argument_type,
+ bool>
+{
+public:
+ explicit binary_negate(const Predicate& pred);
+ bool operator()(const typename Predicate::first_argument_type& x,
+ const typename Predicate::second_argument_type& y) const;
+};
+
+template <class Predicate> // deprecated in C++17, removed in C++20
+binary_negate<Predicate> not2(const Predicate& pred);
+
+template <class F>
+constexpr unspecified not_fn(F&& f); // C++17, constexpr in C++20
+
+// [func.bind.partial], function templates bind_front and bind_back
+template<class F, class... Args>
+ constexpr unspecified bind_front(F&&, Args&&...); // C++20
+template<class F, class... Args>
+ constexpr unspecified bind_back(F&&, Args&&...); // C++23
+
+template<class T> struct is_bind_expression;
+template<class T> struct is_placeholder;
+
+ // See C++14 20.9.9, Function object binders
+template <class T> inline constexpr bool is_bind_expression_v
+ = is_bind_expression<T>::value; // C++17
+template <class T> inline constexpr int is_placeholder_v
+ = is_placeholder<T>::value; // C++17
+
+
+template<class Fn, class... BoundArgs>
+ constexpr unspecified bind(Fn&&, BoundArgs&&...); // constexpr in C++20
+template<class R, class Fn, class... BoundArgs>
+ constexpr unspecified bind(Fn&&, BoundArgs&&...); // constexpr in C++20
+
+// [func.invoke]
+template<class F, class... Args>
+ constexpr // constexpr in C++20
+ invoke_result_t<F, Args...> invoke(F&& f, Args&&... args) // C++17
+ noexcept(is_nothrow_invocable_v<F, Args...>);
+
+template<class R, class F, class... Args>
+ constexpr R invoke_r(F&& f, Args&&... args) // C++23
+ noexcept(is_nothrow_invocable_r_v<R, F, Args...>);
+
+namespace placeholders {
+ // M is the implementation-defined number of placeholders
+ extern unspecified _1;
+ extern unspecified _2;
+ .
+ .
+ .
+ extern unspecified _Mp;
+}
+
+template <class Operation>
+class binder1st // deprecated in C++11, removed in C++17
+ : public unary_function<typename Operation::second_argument_type,
+ typename Operation::result_type>
+{
+protected:
+ Operation op;
+ typename Operation::first_argument_type value;
+public:
+ binder1st(const Operation& x, const typename Operation::first_argument_type y);
+ typename Operation::result_type operator()( typename Operation::second_argument_type& x) const;
+ typename Operation::result_type operator()(const typename Operation::second_argument_type& x) const;
+};
+
+template <class Operation, class T>
+binder1st<Operation> bind1st(const Operation& op, const T& x); // deprecated in C++11, removed in C++17
+
+template <class Operation>
+class binder2nd // deprecated in C++11, removed in C++17
+ : public unary_function<typename Operation::first_argument_type,
+ typename Operation::result_type>
+{
+protected:
+ Operation op;
+ typename Operation::second_argument_type value;
+public:
+ binder2nd(const Operation& x, const typename Operation::second_argument_type y);
+ typename Operation::result_type operator()( typename Operation::first_argument_type& x) const;
+ typename Operation::result_type operator()(const typename Operation::first_argument_type& x) const;
+};
+
+template <class Operation, class T>
+binder2nd<Operation> bind2nd(const Operation& op, const T& x); // deprecated in C++11, removed in C++17
+
+template <class Arg, class Result> // deprecated in C++11, removed in C++17
+class pointer_to_unary_function : public unary_function<Arg, Result>
+{
+public:
+ explicit pointer_to_unary_function(Result (*f)(Arg));
+ Result operator()(Arg x) const;
+};
+
+template <class Arg, class Result>
+pointer_to_unary_function<Arg,Result> ptr_fun(Result (*f)(Arg)); // deprecated in C++11, removed in C++17
+
+template <class Arg1, class Arg2, class Result> // deprecated in C++11, removed in C++17
+class pointer_to_binary_function : public binary_function<Arg1, Arg2, Result>
+{
+public:
+ explicit pointer_to_binary_function(Result (*f)(Arg1, Arg2));
+ Result operator()(Arg1 x, Arg2 y) const;
+};
+
+template <class Arg1, class Arg2, class Result>
+pointer_to_binary_function<Arg1,Arg2,Result> ptr_fun(Result (*f)(Arg1,Arg2)); // deprecated in C++11, removed in C++17
+
+template<class S, class T> // deprecated in C++11, removed in C++17
+class mem_fun_t : public unary_function<T*, S>
+{
+public:
+ explicit mem_fun_t(S (T::*p)());
+ S operator()(T* p) const;
+};
+
+template<class S, class T, class A>
+class mem_fun1_t : public binary_function<T*, A, S> // deprecated in C++11, removed in C++17
+{
+public:
+ explicit mem_fun1_t(S (T::*p)(A));
+ S operator()(T* p, A x) const;
+};
+
+template<class S, class T> mem_fun_t<S,T> mem_fun(S (T::*f)()); // deprecated in C++11, removed in C++17
+template<class S, class T, class A> mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A)); // deprecated in C++11, removed in C++17
+
+template<class S, class T>
+class mem_fun_ref_t : public unary_function<T, S> // deprecated in C++11, removed in C++17
+{
+public:
+ explicit mem_fun_ref_t(S (T::*p)());
+ S operator()(T& p) const;
+};
+
+template<class S, class T, class A>
+class mem_fun1_ref_t : public binary_function<T, A, S> // deprecated in C++11, removed in C++17
+{
+public:
+ explicit mem_fun1_ref_t(S (T::*p)(A));
+ S operator()(T& p, A x) const;
+};
+
+template<class S, class T>
+mem_fun_ref_t<S,T> mem_fun_ref(S (T::*f)()); // deprecated in C++11, removed in C++17
+template<class S, class T, class A>
+mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A)); // deprecated in C++11, removed in C++17
+
+template <class S, class T>
+class const_mem_fun_t : public unary_function<const T*, S> // deprecated in C++11, removed in C++17
+{
+public:
+ explicit const_mem_fun_t(S (T::*p)() const);
+ S operator()(const T* p) const;
+};
+
+template <class S, class T, class A>
+class const_mem_fun1_t : public binary_function<const T*, A, S> // deprecated in C++11, removed in C++17
+{
+public:
+ explicit const_mem_fun1_t(S (T::*p)(A) const);
+ S operator()(const T* p, A x) const;
+};
+
+template <class S, class T>
+const_mem_fun_t<S,T> mem_fun(S (T::*f)() const); // deprecated in C++11, removed in C++17
+template <class S, class T, class A>
+const_mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A) const); // deprecated in C++11, removed in C++17
+
+template <class S, class T>
+class const_mem_fun_ref_t : public unary_function<T, S> // deprecated in C++11, removed in C++17
+{
+public:
+ explicit const_mem_fun_ref_t(S (T::*p)() const);
+ S operator()(const T& p) const;
+};
+
+template <class S, class T, class A>
+class const_mem_fun1_ref_t : public binary_function<T, A, S> // deprecated in C++11, removed in C++17
+{
+public:
+ explicit const_mem_fun1_ref_t(S (T::*p)(A) const);
+ S operator()(const T& p, A x) const;
+};
+
+template <class S, class T>
+const_mem_fun_ref_t<S,T> mem_fun_ref(S (T::*f)() const); // deprecated in C++11, removed in C++17
+template <class S, class T, class A>
+const_mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A) const); // deprecated in C++11, removed in C++17
+
+template<class R, class T> constexpr unspecified mem_fn(R T::*); // constexpr in C++20
+
+class bad_function_call
+ : public exception
+{
+};
+
+template<class> class function; // undefined
+
+template<class R, class... ArgTypes>
+class function<R(ArgTypes...)>
+ : public unary_function<T1, R> // iff sizeof...(ArgTypes) == 1 and
+ // ArgTypes contains T1
+ : public binary_function<T1, T2, R> // iff sizeof...(ArgTypes) == 2 and
+ // ArgTypes contains T1 and T2
+{
+public:
+ typedef R result_type;
+
+ // construct/copy/destroy:
+ function() noexcept;
+ function(nullptr_t) noexcept;
+ function(const function&);
+ function(function&&) noexcept;
+ template<class F>
+ function(F);
+ template<Allocator Alloc>
+ function(allocator_arg_t, const Alloc&) noexcept; // removed in C++17
+ template<Allocator Alloc>
+ function(allocator_arg_t, const Alloc&, nullptr_t) noexcept; // removed in C++17
+ template<Allocator Alloc>
+ function(allocator_arg_t, const Alloc&, const function&); // removed in C++17
+ template<Allocator Alloc>
+ function(allocator_arg_t, const Alloc&, function&&); // removed in C++17
+ template<class F, Allocator Alloc>
+ function(allocator_arg_t, const Alloc&, F); // removed in C++17
+
+ function& operator=(const function&);
+ function& operator=(function&&) noexcept;
+ function& operator=(nullptr_t) noexcept;
+ template<class F>
+ function& operator=(F&&);
+ template<class F>
+ function& operator=(reference_wrapper<F>) noexcept;
+
+ ~function();
+
+ // function modifiers:
+ void swap(function&) noexcept;
+ template<class F, class Alloc>
+ void assign(F&&, const Alloc&); // Removed in C++17
+
+ // function capacity:
+ explicit operator bool() const noexcept;
+
+ // function invocation:
+ R operator()(ArgTypes...) const;
+
+ // function target access:
+ const std::type_info& target_type() const noexcept;
+ template <typename T> T* target() noexcept;
+ template <typename T> const T* target() const noexcept;
+};
+
+// Deduction guides
+template<class R, class ...Args>
+function(R(*)(Args...)) -> function<R(Args...)>; // since C++17
+
+template<class F>
+function(F) -> function<see-below>; // since C++17
+
+// Null pointer comparisons:
+template <class R, class ... ArgTypes>
+ bool operator==(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
+
+template <class R, class ... ArgTypes>
+ bool operator==(nullptr_t, const function<R(ArgTypes...)>&) noexcept; // removed in C++20
+
+template <class R, class ... ArgTypes>
+ bool operator!=(const function<R(ArgTypes...)>&, nullptr_t) noexcept; // removed in C++20
+
+template <class R, class ... ArgTypes>
+ bool operator!=(nullptr_t, const function<R(ArgTypes...)>&) noexcept; // removed in C++20
+
+// specialized algorithms:
+template <class R, class ... ArgTypes>
+ void swap(function<R(ArgTypes...)>&, function<R(ArgTypes...)>&) noexcept;
+
+template <class T> struct hash;
+
+template <> struct hash<bool>;
+template <> struct hash<char>;
+template <> struct hash<signed char>;
+template <> struct hash<unsigned char>;
+template <> struct hash<char8_t>; // since C++20
+template <> struct hash<char16_t>;
+template <> struct hash<char32_t>;
+template <> struct hash<wchar_t>;
+template <> struct hash<short>;
+template <> struct hash<unsigned short>;
+template <> struct hash<int>;
+template <> struct hash<unsigned int>;
+template <> struct hash<long>;
+template <> struct hash<long long>;
+template <> struct hash<unsigned long>;
+template <> struct hash<unsigned long long>;
+
+template <> struct hash<float>;
+template <> struct hash<double>;
+template <> struct hash<long double>;
+
+template<class T> struct hash<T*>;
+template <> struct hash<nullptr_t>; // C++17
+
+namespace ranges {
+ // [range.cmp], concept-constrained comparisons
+ struct equal_to;
+ struct not_equal_to;
+ struct greater;
+ struct less;
+ struct greater_equal;
+ struct less_equal;
+}
+
+} // std
+
+POLICY: For non-variadic implementations, the number of arguments is limited
+ to 3. It is hoped that the need for non-variadic implementations
+ will be minimal.
+
+*/
+
+#include <__config>
+
+#include <__functional/binary_function.h>
+#include <__functional/binary_negate.h>
+#include <__functional/bind.h>
+#include <__functional/binder1st.h>
+#include <__functional/binder2nd.h>
+#include <__functional/hash.h>
+#include <__functional/mem_fn.h> // TODO: deprecate
+#include <__functional/mem_fun_ref.h>
+#include <__functional/operations.h>
+#include <__functional/pointer_to_binary_function.h>
+#include <__functional/pointer_to_unary_function.h>
+#include <__functional/reference_wrapper.h>
+#include <__functional/unary_function.h>
+#include <__functional/unary_negate.h>
+
+#ifndef _LIBCPP_CXX03_LANG
+# include <__functional/function.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+# include <__functional/boyer_moore_searcher.h>
+# include <__functional/default_searcher.h>
+# include <__functional/invoke.h>
+# include <__functional/not_fn.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+# include <__functional/bind_back.h>
+# include <__functional/bind_front.h>
+# include <__functional/identity.h>
+# include <__functional/ranges_operations.h>
+# include <__type_traits/unwrap_ref.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && defined(_LIBCPP_CXX03_LANG)
+# include <limits>
+# include <new>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 14
+# include <array>
+# include <initializer_list>
+# include <unordered_map>
+# include <vector>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstdlib>
+# include <exception>
+# include <iosfwd>
+# include <memory>
+# include <stdexcept>
+# include <tuple>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_FUNCTIONAL
diff --git a/libcxx/include/__cxx03/future b/libcxx/include/__cxx03/future
new file mode 100644
index 00000000000000..0be32620139e37
--- /dev/null
+++ b/libcxx/include/__cxx03/future
@@ -0,0 +1,2062 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_FUTURE
+#define _LIBCPP_FUTURE
+
+/*
+ future synopsis
+
+namespace std
+{
+
+enum class future_errc
+{
+ future_already_retrieved = 1,
+ promise_already_satisfied,
+ no_state,
+ broken_promise
+};
+
+enum class launch
+{
+ async = 1,
+ deferred = 2,
+ any = async | deferred
+};
+
+enum class future_status
+{
+ ready,
+ timeout,
+ deferred
+};
+
+template <> struct is_error_code_enum<future_errc> : public true_type { };
+error_code make_error_code(future_errc e) noexcept;
+error_condition make_error_condition(future_errc e) noexcept;
+
+const error_category& future_category() noexcept;
+
+class future_error : public logic_error {
+public:
+ explicit future_error(future_errc e); // since C++17
+
+ const error_code& code() const noexcept;
+ const char* what() const noexcept;
+
+private:
+ error_code ec_; // exposition only
+};
+
+template <class R>
+class promise
+{
+public:
+ promise();
+ template <class Allocator>
+ promise(allocator_arg_t, const Allocator& a);
+ promise(promise&& rhs) noexcept;
+ promise(const promise& rhs) = delete;
+ ~promise();
+
+ // assignment
+ promise& operator=(promise&& rhs) noexcept;
+ promise& operator=(const promise& rhs) = delete;
+ void swap(promise& other) noexcept;
+
+ // retrieving the result
+ future<R> get_future();
+
+ // setting the result
+ void set_value(const R& r);
+ void set_value(R&& r);
+ void set_exception(exception_ptr p);
+
+ // setting the result with deferred notification
+ void set_value_at_thread_exit(const R& r);
+ void set_value_at_thread_exit(R&& r);
+ void set_exception_at_thread_exit(exception_ptr p);
+};
+
+template <class R>
+class promise<R&>
+{
+public:
+ promise();
+ template <class Allocator>
+ promise(allocator_arg_t, const Allocator& a);
+ promise(promise&& rhs) noexcept;
+ promise(const promise& rhs) = delete;
+ ~promise();
+
+ // assignment
+ promise& operator=(promise&& rhs) noexcept;
+ promise& operator=(const promise& rhs) = delete;
+ void swap(promise& other) noexcept;
+
+ // retrieving the result
+ future<R&> get_future();
+
+ // setting the result
+ void set_value(R& r);
+ void set_exception(exception_ptr p);
+
+ // setting the result with deferred notification
+ void set_value_at_thread_exit(R&);
+ void set_exception_at_thread_exit(exception_ptr p);
+};
+
+template <>
+class promise<void>
+{
+public:
+ promise();
+ template <class Allocator>
+ promise(allocator_arg_t, const Allocator& a);
+ promise(promise&& rhs) noexcept;
+ promise(const promise& rhs) = delete;
+ ~promise();
+
+ // assignment
+ promise& operator=(promise&& rhs) noexcept;
+ promise& operator=(const promise& rhs) = delete;
+ void swap(promise& other) noexcept;
+
+ // retrieving the result
+ future<void> get_future();
+
+ // setting the result
+ void set_value();
+ void set_exception(exception_ptr p);
+
+ // setting the result with deferred notification
+ void set_value_at_thread_exit();
+ void set_exception_at_thread_exit(exception_ptr p);
+};
+
+template <class R> void swap(promise<R>& x, promise<R>& y) noexcept;
+
+template <class R, class Alloc>
+ struct uses_allocator<promise<R>, Alloc> : public true_type {};
+
+template <class R>
+class future
+{
+public:
+ future() noexcept;
+ future(future&&) noexcept;
+ future(const future& rhs) = delete;
+ ~future();
+ future& operator=(const future& rhs) = delete;
+ future& operator=(future&&) noexcept;
+ shared_future<R> share() noexcept;
+
+ // retrieving the value
+ R get();
+
+ // functions to check state
+ bool valid() const noexcept;
+
+ void wait() const;
+ template <class Rep, class Period>
+ future_status
+ wait_for(const chrono::duration<Rep, Period>& rel_time) const;
+ template <class Clock, class Duration>
+ future_status
+ wait_until(const chrono::time_point<Clock, Duration>& abs_time) const;
+};
+
+template <class R>
+class future<R&>
+{
+public:
+ future() noexcept;
+ future(future&&) noexcept;
+ future(const future& rhs) = delete;
+ ~future();
+ future& operator=(const future& rhs) = delete;
+ future& operator=(future&&) noexcept;
+ shared_future<R&> share() noexcept;
+
+ // retrieving the value
+ R& get();
+
+ // functions to check state
+ bool valid() const noexcept;
+
+ void wait() const;
+ template <class Rep, class Period>
+ future_status
+ wait_for(const chrono::duration<Rep, Period>& rel_time) const;
+ template <class Clock, class Duration>
+ future_status
+ wait_until(const chrono::time_point<Clock, Duration>& abs_time) const;
+};
+
+template <>
+class future<void>
+{
+public:
+ future() noexcept;
+ future(future&&) noexcept;
+ future(const future& rhs) = delete;
+ ~future();
+ future& operator=(const future& rhs) = delete;
+ future& operator=(future&&) noexcept;
+ shared_future<void> share() noexcept;
+
+ // retrieving the value
+ void get();
+
+ // functions to check state
+ bool valid() const noexcept;
+
+ void wait() const;
+ template <class Rep, class Period>
+ future_status
+ wait_for(const chrono::duration<Rep, Period>& rel_time) const;
+ template <class Clock, class Duration>
+ future_status
+ wait_until(const chrono::time_point<Clock, Duration>& abs_time) const;
+};
+
+template <class R>
+class shared_future
+{
+public:
+ shared_future() noexcept;
+ shared_future(const shared_future& rhs);
+ shared_future(future<R>&&) noexcept;
+ shared_future(shared_future&& rhs) noexcept;
+ ~shared_future();
+ shared_future& operator=(const shared_future& rhs);
+ shared_future& operator=(shared_future&& rhs) noexcept;
+
+ // retrieving the value
+ const R& get() const;
+
+ // functions to check state
+ bool valid() const noexcept;
+
+ void wait() const;
+ template <class Rep, class Period>
+ future_status
+ wait_for(const chrono::duration<Rep, Period>& rel_time) const;
+ template <class Clock, class Duration>
+ future_status
+ wait_until(const chrono::time_point<Clock, Duration>& abs_time) const;
+};
+
+template <class R>
+class shared_future<R&>
+{
+public:
+ shared_future() noexcept;
+ shared_future(const shared_future& rhs);
+ shared_future(future<R&>&&) noexcept;
+ shared_future(shared_future&& rhs) noexcept;
+ ~shared_future();
+ shared_future& operator=(const shared_future& rhs);
+ shared_future& operator=(shared_future&& rhs) noexcept;
+
+ // retrieving the value
+ R& get() const;
+
+ // functions to check state
+ bool valid() const noexcept;
+
+ void wait() const;
+ template <class Rep, class Period>
+ future_status
+ wait_for(const chrono::duration<Rep, Period>& rel_time) const;
+ template <class Clock, class Duration>
+ future_status
+ wait_until(const chrono::time_point<Clock, Duration>& abs_time) const;
+};
+
+template <>
+class shared_future<void>
+{
+public:
+ shared_future() noexcept;
+ shared_future(const shared_future& rhs);
+ shared_future(future<void>&&) noexcept;
+ shared_future(shared_future&& rhs) noexcept;
+ ~shared_future();
+ shared_future& operator=(const shared_future& rhs);
+ shared_future& operator=(shared_future&& rhs) noexcept;
+
+ // retrieving the value
+ void get() const;
+
+ // functions to check state
+ bool valid() const noexcept;
+
+ void wait() const;
+ template <class Rep, class Period>
+ future_status
+ wait_for(const chrono::duration<Rep, Period>& rel_time) const;
+ template <class Clock, class Duration>
+ future_status
+ wait_until(const chrono::time_point<Clock, Duration>& abs_time) const;
+};
+
+template <class F, class... Args>
+ future<typename result_of<typename decay<F>::type(typename decay<Args>::type...)>::type>
+ async(F&& f, Args&&... args);
+
+template <class F, class... Args>
+ future<typename result_of<typename decay<F>::type(typename decay<Args>::type...)>::type>
+ async(launch policy, F&& f, Args&&... args);
+
+template <class> class packaged_task; // undefined
+
+template <class R, class... ArgTypes>
+class packaged_task<R(ArgTypes...)>
+{
+public:
+ typedef R result_type; // extension
+
+ // construction and destruction
+ packaged_task() noexcept;
+ template <class F>
+ explicit packaged_task(F&& f);
+ template <class F, class Allocator>
+ packaged_task(allocator_arg_t, const Allocator& a, F&& f);
+ ~packaged_task();
+
+ // no copy
+ packaged_task(const packaged_task&) = delete;
+ packaged_task& operator=(const packaged_task&) = delete;
+
+ // move support
+ packaged_task(packaged_task&& other) noexcept;
+ packaged_task& operator=(packaged_task&& other) noexcept;
+ void swap(packaged_task& other) noexcept;
+
+ bool valid() const noexcept;
+
+ // result retrieval
+ future<R> get_future();
+
+ // execution
+ void operator()(ArgTypes... );
+ void make_ready_at_thread_exit(ArgTypes...);
+
+ void reset();
+};
+
+template <class R>
+ void swap(packaged_task<R(ArgTypes...)&, packaged_task<R(ArgTypes...)>&) noexcept;
+
+template <class R, class Alloc> struct uses_allocator<packaged_task<R>, Alloc>;
+
+} // std
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+# include <__assert>
+# include <__chrono/duration.h>
+# include <__chrono/time_point.h>
+# include <__exception/exception_ptr.h>
+# include <__memory/addressof.h>
+# include <__memory/allocator.h>
+# include <__memory/allocator_arg_t.h>
+# include <__memory/allocator_destructor.h>
+# include <__memory/allocator_traits.h>
+# include <__memory/compressed_pair.h>
+# include <__memory/pointer_traits.h>
+# include <__memory/shared_ptr.h>
+# include <__memory/unique_ptr.h>
+# include <__memory/uses_allocator.h>
+# include <__system_error/error_category.h>
+# include <__system_error/error_code.h>
+# include <__system_error/error_condition.h>
+# include <__type_traits/aligned_storage.h>
+# include <__type_traits/strip_signature.h>
+# include <__utility/auto_cast.h>
+# include <__utility/forward.h>
+# include <__utility/move.h>
+# include <mutex>
+# include <new>
+# include <stdexcept>
+# include <thread>
+# include <version>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// enum class future_errc
+_LIBCPP_DECLARE_STRONG_ENUM(future_errc){
+ future_already_retrieved = 1, promise_already_satisfied, no_state, broken_promise};
+_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(future_errc)
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS is_error_code_enum<future_errc> : public true_type {};
+
+# ifdef _LIBCPP_CXX03_LANG
+template <>
+struct _LIBCPP_TEMPLATE_VIS is_error_code_enum<future_errc::__lx> : public true_type {};
+# endif
+
+// enum class launch
+_LIBCPP_DECLARE_STRONG_ENUM(launch){async = 1, deferred = 2, any = async | deferred};
+_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(launch)
+
+# ifndef _LIBCPP_CXX03_LANG
+
+typedef underlying_type<launch>::type __launch_underlying_type;
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr launch operator&(launch __x, launch __y) {
+ return static_cast<launch>(static_cast<__launch_underlying_type>(__x) & static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr launch operator|(launch __x, launch __y) {
+ return static_cast<launch>(static_cast<__launch_underlying_type>(__x) | static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr launch operator^(launch __x, launch __y) {
+ return static_cast<launch>(static_cast<__launch_underlying_type>(__x) ^ static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr launch operator~(launch __x) {
+ return static_cast<launch>(~static_cast<__launch_underlying_type>(__x) & 3);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI launch& operator&=(launch& __x, launch __y) {
+ __x = __x & __y;
+ return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI launch& operator|=(launch& __x, launch __y) {
+ __x = __x | __y;
+ return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI launch& operator^=(launch& __x, launch __y) {
+ __x = __x ^ __y;
+ return __x;
+}
+
+# endif // !_LIBCPP_CXX03_LANG
+
+// enum class future_status
+_LIBCPP_DECLARE_STRONG_ENUM(future_status){ready, timeout, deferred};
+_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(future_status)
+
+_LIBCPP_EXPORTED_FROM_ABI const error_category& future_category() _NOEXCEPT;
+
+inline _LIBCPP_HIDE_FROM_ABI error_code make_error_code(future_errc __e) _NOEXCEPT {
+ return error_code(static_cast<int>(__e), future_category());
+}
+
+inline _LIBCPP_HIDE_FROM_ABI error_condition make_error_condition(future_errc __e) _NOEXCEPT {
+ return error_condition(static_cast<int>(__e), future_category());
+}
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_future_error(future_errc __ev);
+
+class _LIBCPP_EXPORTED_FROM_ABI future_error : public logic_error {
+ error_code __ec_;
+
+ future_error(error_code);
+ friend void __throw_future_error(future_errc);
+ template <class>
+ friend class promise;
+
+public:
+# if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI explicit future_error(future_errc __ec) : future_error(std::make_error_code(__ec)) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI const error_code& code() const _NOEXCEPT { return __ec_; }
+
+ _LIBCPP_HIDE_FROM_ABI future_error(const future_error&) _NOEXCEPT = default;
+ ~future_error() _NOEXCEPT override;
+};
+
+// Declared above std::future_error
+void __throw_future_error(future_errc __ev) {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw future_error(make_error_code(__ev));
+# else
+ (void)__ev;
+ _LIBCPP_VERBOSE_ABORT("future_error was thrown in -fno-exceptions mode");
+# endif
+}
+
+class _LIBCPP_EXPORTED_FROM_ABI __assoc_sub_state : public __shared_count {
+protected:
+ exception_ptr __exception_;
+ mutable mutex __mut_;
+ mutable condition_variable __cv_;
+ unsigned __state_;
+
+ void __on_zero_shared() _NOEXCEPT override;
+ void __sub_wait(unique_lock<mutex>& __lk);
+
+public:
+ enum { __constructed = 1, __future_attached = 2, ready = 4, deferred = 8 };
+
+ _LIBCPP_HIDE_FROM_ABI __assoc_sub_state() : __state_(0) {}
+
+ _LIBCPP_HIDE_FROM_ABI bool __has_value() const { return (__state_ & __constructed) || (__exception_ != nullptr); }
+
+ _LIBCPP_HIDE_FROM_ABI void __attach_future() {
+ lock_guard<mutex> __lk(__mut_);
+ bool __has_future_attached = (__state_ & __future_attached) != 0;
+ if (__has_future_attached)
+ __throw_future_error(future_errc::future_already_retrieved);
+ this->__add_shared();
+ __state_ |= __future_attached;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __set_deferred() { __state_ |= deferred; }
+
+ void __make_ready();
+ _LIBCPP_HIDE_FROM_ABI bool __is_ready() const { return (__state_ & ready) != 0; }
+
+ void set_value();
+ void set_value_at_thread_exit();
+
+ void set_exception(exception_ptr __p);
+ void set_exception_at_thread_exit(exception_ptr __p);
+
+ void copy();
+
+ void wait();
+ template <class _Rep, class _Period>
+ future_status _LIBCPP_HIDE_FROM_ABI wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const;
+ template <class _Clock, class _Duration>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS future_status
+ wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const;
+
+ virtual void __execute();
+};
+
+template <class _Clock, class _Duration>
+future_status __assoc_sub_state::wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const {
+ unique_lock<mutex> __lk(__mut_);
+ if (__state_ & deferred)
+ return future_status::deferred;
+ while (!(__state_ & ready) && _Clock::now() < __abs_time)
+ __cv_.wait_until(__lk, __abs_time);
+ if (__state_ & ready)
+ return future_status::ready;
+ return future_status::timeout;
+}
+
+template <class _Rep, class _Period>
+inline future_status __assoc_sub_state::wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const {
+ return wait_until(chrono::steady_clock::now() + __rel_time);
+}
+
+template <class _Rp>
+class _LIBCPP_HIDDEN __assoc_state : public __assoc_sub_state {
+ typedef __assoc_sub_state base;
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ typedef typename aligned_storage<sizeof(_Rp), _LIBCPP_ALIGNOF(_Rp)>::type _Up;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+
+protected:
+ _Up __value_;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared() _NOEXCEPT override;
+
+public:
+ template <class _Arg>
+ _LIBCPP_HIDE_FROM_ABI void set_value(_Arg&& __arg);
+
+ template <class _Arg>
+ _LIBCPP_HIDE_FROM_ABI void set_value_at_thread_exit(_Arg&& __arg);
+
+ _LIBCPP_HIDE_FROM_ABI _Rp move();
+ _LIBCPP_HIDE_FROM_ABI __add_lvalue_reference_t<_Rp> copy();
+};
+
+template <class _Rp>
+void __assoc_state<_Rp>::__on_zero_shared() _NOEXCEPT {
+ if (this->__state_ & base::__constructed)
+ reinterpret_cast<_Rp*>(&__value_)->~_Rp();
+ delete this;
+}
+
+template <class _Rp>
+template <class _Arg>
+void __assoc_state<_Rp>::set_value(_Arg&& __arg) {
+ unique_lock<mutex> __lk(this->__mut_);
+ if (this->__has_value())
+ __throw_future_error(future_errc::promise_already_satisfied);
+ ::new ((void*)&__value_) _Rp(std::forward<_Arg>(__arg));
+ this->__state_ |= base::__constructed | base::ready;
+ __cv_.notify_all();
+}
+
+template <class _Rp>
+template <class _Arg>
+void __assoc_state<_Rp>::set_value_at_thread_exit(_Arg&& __arg) {
+ unique_lock<mutex> __lk(this->__mut_);
+ if (this->__has_value())
+ __throw_future_error(future_errc::promise_already_satisfied);
+ ::new ((void*)&__value_) _Rp(std::forward<_Arg>(__arg));
+ this->__state_ |= base::__constructed;
+ __thread_local_data()->__make_ready_at_thread_exit(this);
+}
+
+template <class _Rp>
+_Rp __assoc_state<_Rp>::move() {
+ unique_lock<mutex> __lk(this->__mut_);
+ this->__sub_wait(__lk);
+ if (this->__exception_ != nullptr)
+ std::rethrow_exception(this->__exception_);
+ return std::move(*reinterpret_cast<_Rp*>(&__value_));
+}
+
+template <class _Rp>
+__add_lvalue_reference_t<_Rp> __assoc_state<_Rp>::copy() {
+ unique_lock<mutex> __lk(this->__mut_);
+ this->__sub_wait(__lk);
+ if (this->__exception_ != nullptr)
+ std::rethrow_exception(this->__exception_);
+ return *reinterpret_cast<_Rp*>(&__value_);
+}
+
+template <class _Rp>
+class __assoc_state<_Rp&> : public __assoc_sub_state {
+ typedef __assoc_sub_state base;
+ typedef _Rp* _Up;
+
+protected:
+ _Up __value_;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared() _NOEXCEPT override;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI void set_value(_Rp& __arg);
+ _LIBCPP_HIDE_FROM_ABI void set_value_at_thread_exit(_Rp& __arg);
+
+ _LIBCPP_HIDE_FROM_ABI _Rp& copy();
+};
+
+template <class _Rp>
+void __assoc_state<_Rp&>::__on_zero_shared() _NOEXCEPT {
+ delete this;
+}
+
+template <class _Rp>
+void __assoc_state<_Rp&>::set_value(_Rp& __arg) {
+ unique_lock<mutex> __lk(this->__mut_);
+ if (this->__has_value())
+ __throw_future_error(future_errc::promise_already_satisfied);
+ __value_ = std::addressof(__arg);
+ this->__state_ |= base::__constructed | base::ready;
+ __cv_.notify_all();
+}
+
+template <class _Rp>
+void __assoc_state<_Rp&>::set_value_at_thread_exit(_Rp& __arg) {
+ unique_lock<mutex> __lk(this->__mut_);
+ if (this->__has_value())
+ __throw_future_error(future_errc::promise_already_satisfied);
+ __value_ = std::addressof(__arg);
+ this->__state_ |= base::__constructed;
+ __thread_local_data()->__make_ready_at_thread_exit(this);
+}
+
+template <class _Rp>
+_Rp& __assoc_state<_Rp&>::copy() {
+ unique_lock<mutex> __lk(this->__mut_);
+ this->__sub_wait(__lk);
+ if (this->__exception_ != nullptr)
+ std::rethrow_exception(this->__exception_);
+ return *__value_;
+}
+
+template <class _Rp, class _Alloc>
+class __assoc_state_alloc : public __assoc_state<_Rp> {
+ typedef __assoc_state<_Rp> base;
+ _Alloc __alloc_;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __on_zero_shared() _NOEXCEPT;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __assoc_state_alloc(const _Alloc& __a) : __alloc_(__a) {}
+};
+
+template <class _Rp, class _Alloc>
+void __assoc_state_alloc<_Rp, _Alloc>::__on_zero_shared() _NOEXCEPT {
+ if (this->__state_ & base::__constructed)
+ reinterpret_cast<_Rp*>(std::addressof(this->__value_))->~_Rp();
+ typedef typename __allocator_traits_rebind<_Alloc, __assoc_state_alloc>::type _Al;
+ typedef allocator_traits<_Al> _ATraits;
+ typedef pointer_traits<typename _ATraits::pointer> _PTraits;
+ _Al __a(__alloc_);
+ this->~__assoc_state_alloc();
+ __a.deallocate(_PTraits::pointer_to(*this), 1);
+}
+
+template <class _Rp, class _Alloc>
+class __assoc_state_alloc<_Rp&, _Alloc> : public __assoc_state<_Rp&> {
+ typedef __assoc_state<_Rp&> base;
+ _Alloc __alloc_;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __on_zero_shared() _NOEXCEPT;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __assoc_state_alloc(const _Alloc& __a) : __alloc_(__a) {}
+};
+
+template <class _Rp, class _Alloc>
+void __assoc_state_alloc<_Rp&, _Alloc>::__on_zero_shared() _NOEXCEPT {
+ typedef typename __allocator_traits_rebind<_Alloc, __assoc_state_alloc>::type _Al;
+ typedef allocator_traits<_Al> _ATraits;
+ typedef pointer_traits<typename _ATraits::pointer> _PTraits;
+ _Al __a(__alloc_);
+ this->~__assoc_state_alloc();
+ __a.deallocate(_PTraits::pointer_to(*this), 1);
+}
+
+template <class _Alloc>
+class __assoc_sub_state_alloc : public __assoc_sub_state {
+ typedef __assoc_sub_state base;
+ _Alloc __alloc_;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared() _NOEXCEPT override;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __assoc_sub_state_alloc(const _Alloc& __a) : __alloc_(__a) {}
+};
+
+template <class _Alloc>
+void __assoc_sub_state_alloc<_Alloc>::__on_zero_shared() _NOEXCEPT {
+ typedef typename __allocator_traits_rebind<_Alloc, __assoc_sub_state_alloc>::type _Al;
+ typedef allocator_traits<_Al> _ATraits;
+ typedef pointer_traits<typename _ATraits::pointer> _PTraits;
+ _Al __a(__alloc_);
+ this->~__assoc_sub_state_alloc();
+ __a.deallocate(_PTraits::pointer_to(*this), 1);
+}
+
+template <class _Rp, class _Fp>
+class __deferred_assoc_state : public __assoc_state<_Rp> {
+ typedef __assoc_state<_Rp> base;
+
+ _Fp __func_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __deferred_assoc_state(_Fp&& __f);
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __execute();
+};
+
+template <class _Rp, class _Fp>
+inline __deferred_assoc_state<_Rp, _Fp>::__deferred_assoc_state(_Fp&& __f) : __func_(std::forward<_Fp>(__f)) {
+ this->__set_deferred();
+}
+
+template <class _Rp, class _Fp>
+void __deferred_assoc_state<_Rp, _Fp>::__execute() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ this->set_value(__func_());
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->set_exception(current_exception());
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class _Fp>
+class __deferred_assoc_state<void, _Fp> : public __assoc_sub_state {
+ typedef __assoc_sub_state base;
+
+ _Fp __func_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __deferred_assoc_state(_Fp&& __f);
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __execute() override;
+};
+
+template <class _Fp>
+inline __deferred_assoc_state<void, _Fp>::__deferred_assoc_state(_Fp&& __f) : __func_(std::forward<_Fp>(__f)) {
+ this->__set_deferred();
+}
+
+template <class _Fp>
+void __deferred_assoc_state<void, _Fp>::__execute() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __func_();
+ this->set_value();
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->set_exception(current_exception());
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class _Rp, class _Fp>
+class __async_assoc_state : public __assoc_state<_Rp> {
+ typedef __assoc_state<_Rp> base;
+
+ _Fp __func_;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __on_zero_shared() _NOEXCEPT;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __async_assoc_state(_Fp&& __f);
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __execute();
+};
+
+template <class _Rp, class _Fp>
+inline __async_assoc_state<_Rp, _Fp>::__async_assoc_state(_Fp&& __f) : __func_(std::forward<_Fp>(__f)) {}
+
+template <class _Rp, class _Fp>
+void __async_assoc_state<_Rp, _Fp>::__execute() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ this->set_value(__func_());
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->set_exception(current_exception());
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class _Rp, class _Fp>
+void __async_assoc_state<_Rp, _Fp>::__on_zero_shared() _NOEXCEPT {
+ this->wait();
+ base::__on_zero_shared();
+}
+
+template <class _Fp>
+class __async_assoc_state<void, _Fp> : public __assoc_sub_state {
+ typedef __assoc_sub_state base;
+
+ _Fp __func_;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __on_zero_shared() _NOEXCEPT override;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __async_assoc_state(_Fp&& __f);
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __execute() override;
+};
+
+template <class _Fp>
+inline __async_assoc_state<void, _Fp>::__async_assoc_state(_Fp&& __f) : __func_(std::forward<_Fp>(__f)) {}
+
+template <class _Fp>
+void __async_assoc_state<void, _Fp>::__execute() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __func_();
+ this->set_value();
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->set_exception(current_exception());
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class _Fp>
+void __async_assoc_state<void, _Fp>::__on_zero_shared() _NOEXCEPT {
+ this->wait();
+ base::__on_zero_shared();
+}
+
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS promise;
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS shared_future;
+
+// future
+
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS future;
+
+template <class _Rp, class _Fp>
+_LIBCPP_HIDE_FROM_ABI future<_Rp> __make_deferred_assoc_state(_Fp&& __f);
+
+template <class _Rp, class _Fp>
+_LIBCPP_HIDE_FROM_ABI future<_Rp> __make_async_assoc_state(_Fp&& __f);
+
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS future {
+ __assoc_state<_Rp>* __state_;
+
+ explicit _LIBCPP_HIDE_FROM_ABI future(__assoc_state<_Rp>* __state);
+
+ template <class>
+ friend class promise;
+ template <class>
+ friend class shared_future;
+
+ template <class _R1, class _Fp>
+ friend future<_R1> __make_deferred_assoc_state(_Fp&& __f);
+ template <class _R1, class _Fp>
+ friend future<_R1> __make_async_assoc_state(_Fp&& __f);
+
+public:
+ _LIBCPP_HIDE_FROM_ABI future() _NOEXCEPT : __state_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI future(future&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) { __rhs.__state_ = nullptr; }
+ future(const future&) = delete;
+ future& operator=(const future&) = delete;
+ _LIBCPP_HIDE_FROM_ABI future& operator=(future&& __rhs) _NOEXCEPT {
+ future(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~future();
+ _LIBCPP_HIDE_FROM_ABI shared_future<_Rp> share() _NOEXCEPT;
+
+ // retrieving the value
+ _LIBCPP_HIDE_FROM_ABI _Rp get();
+
+ _LIBCPP_HIDE_FROM_ABI void swap(future& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // functions to check state
+ _LIBCPP_HIDE_FROM_ABI bool valid() const _NOEXCEPT { return __state_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void wait() const { __state_->wait(); }
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const {
+ return __state_->wait_for(__rel_time);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const {
+ return __state_->wait_until(__abs_time);
+ }
+};
+
+template <class _Rp>
+future<_Rp>::future(__assoc_state<_Rp>* __state) : __state_(__state) {
+ __state_->__attach_future();
+}
+
+struct __release_shared_count {
+ _LIBCPP_HIDE_FROM_ABI void operator()(__shared_count* __p) { __p->__release_shared(); }
+};
+
+template <class _Rp>
+future<_Rp>::~future() {
+ if (__state_)
+ __state_->__release_shared();
+}
+
+template <class _Rp>
+_Rp future<_Rp>::get() {
+ unique_ptr<__shared_count, __release_shared_count> __guard(__state_);
+ __assoc_state<_Rp>* __s = __state_;
+ __state_ = nullptr;
+ return __s->move();
+}
+
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS future<_Rp&> {
+ __assoc_state<_Rp&>* __state_;
+
+ explicit _LIBCPP_HIDE_FROM_ABI future(__assoc_state<_Rp&>* __state);
+
+ template <class>
+ friend class promise;
+ template <class>
+ friend class shared_future;
+
+ template <class _R1, class _Fp>
+ friend future<_R1> __make_deferred_assoc_state(_Fp&& __f);
+ template <class _R1, class _Fp>
+ friend future<_R1> __make_async_assoc_state(_Fp&& __f);
+
+public:
+ _LIBCPP_HIDE_FROM_ABI future() _NOEXCEPT : __state_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI future(future&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) { __rhs.__state_ = nullptr; }
+ future(const future&) = delete;
+ future& operator=(const future&) = delete;
+ _LIBCPP_HIDE_FROM_ABI future& operator=(future&& __rhs) _NOEXCEPT {
+ future(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~future();
+ _LIBCPP_HIDE_FROM_ABI shared_future<_Rp&> share() _NOEXCEPT;
+
+ // retrieving the value
+ _LIBCPP_HIDE_FROM_ABI _Rp& get();
+
+ _LIBCPP_HIDE_FROM_ABI void swap(future& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // functions to check state
+ _LIBCPP_HIDE_FROM_ABI bool valid() const _NOEXCEPT { return __state_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void wait() const { __state_->wait(); }
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const {
+ return __state_->wait_for(__rel_time);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const {
+ return __state_->wait_until(__abs_time);
+ }
+};
+
+template <class _Rp>
+future<_Rp&>::future(__assoc_state<_Rp&>* __state) : __state_(__state) {
+ __state_->__attach_future();
+}
+
+template <class _Rp>
+future<_Rp&>::~future() {
+ if (__state_)
+ __state_->__release_shared();
+}
+
+template <class _Rp>
+_Rp& future<_Rp&>::get() {
+ unique_ptr<__shared_count, __release_shared_count> __guard(__state_);
+ __assoc_state<_Rp&>* __s = __state_;
+ __state_ = nullptr;
+ return __s->copy();
+}
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI future<void> {
+ __assoc_sub_state* __state_;
+
+ explicit future(__assoc_sub_state* __state);
+
+ template <class>
+ friend class promise;
+ template <class>
+ friend class shared_future;
+
+ template <class _R1, class _Fp>
+ friend future<_R1> __make_deferred_assoc_state(_Fp&& __f);
+ template <class _R1, class _Fp>
+ friend future<_R1> __make_async_assoc_state(_Fp&& __f);
+
+public:
+ _LIBCPP_HIDE_FROM_ABI future() _NOEXCEPT : __state_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI future(future&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) { __rhs.__state_ = nullptr; }
+ future(const future&) = delete;
+ future& operator=(const future&) = delete;
+ _LIBCPP_HIDE_FROM_ABI future& operator=(future&& __rhs) _NOEXCEPT {
+ future(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ ~future();
+ _LIBCPP_HIDE_FROM_ABI shared_future<void> share() _NOEXCEPT;
+
+ // retrieving the value
+ void get();
+
+ _LIBCPP_HIDE_FROM_ABI void swap(future& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // functions to check state
+ _LIBCPP_HIDE_FROM_ABI bool valid() const _NOEXCEPT { return __state_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void wait() const { __state_->wait(); }
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const {
+ return __state_->wait_for(__rel_time);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const {
+ return __state_->wait_until(__abs_time);
+ }
+};
+
+template <class _Rp>
+inline _LIBCPP_HIDE_FROM_ABI void swap(future<_Rp>& __x, future<_Rp>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+// promise<R>
+
+template <class _Callable>
+class packaged_task;
+
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS promise {
+ __assoc_state<_Rp>* __state_;
+
+ _LIBCPP_HIDE_FROM_ABI explicit promise(nullptr_t) _NOEXCEPT : __state_(nullptr) {}
+
+ template <class>
+ friend class packaged_task;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI promise();
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI promise(allocator_arg_t, const _Alloc& __a);
+ _LIBCPP_HIDE_FROM_ABI promise(promise&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) { __rhs.__state_ = nullptr; }
+ promise(const promise& __rhs) = delete;
+ _LIBCPP_HIDE_FROM_ABI ~promise();
+
+ // assignment
+ _LIBCPP_HIDE_FROM_ABI promise& operator=(promise&& __rhs) _NOEXCEPT {
+ promise(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+ promise& operator=(const promise& __rhs) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(promise& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // retrieving the result
+ _LIBCPP_HIDE_FROM_ABI future<_Rp> get_future();
+
+ // setting the result
+ _LIBCPP_HIDE_FROM_ABI void set_value(const _Rp& __r);
+ _LIBCPP_HIDE_FROM_ABI void set_value(_Rp&& __r);
+ _LIBCPP_HIDE_FROM_ABI void set_exception(exception_ptr __p);
+
+ // setting the result with deferred notification
+ _LIBCPP_HIDE_FROM_ABI void set_value_at_thread_exit(const _Rp& __r);
+ _LIBCPP_HIDE_FROM_ABI void set_value_at_thread_exit(_Rp&& __r);
+ _LIBCPP_HIDE_FROM_ABI void set_exception_at_thread_exit(exception_ptr __p);
+};
+
+template <class _Rp>
+promise<_Rp>::promise() : __state_(new __assoc_state<_Rp>) {}
+
+template <class _Rp>
+template <class _Alloc>
+promise<_Rp>::promise(allocator_arg_t, const _Alloc& __a0) {
+ typedef __assoc_state_alloc<_Rp, _Alloc> _State;
+ typedef typename __allocator_traits_rebind<_Alloc, _State>::type _A2;
+ typedef __allocator_destructor<_A2> _D2;
+ _A2 __a(__a0);
+ unique_ptr<_State, _D2> __hold(__a.allocate(1), _D2(__a, 1));
+ ::new ((void*)std::addressof(*__hold.get())) _State(__a0);
+ __state_ = std::addressof(*__hold.release());
+}
+
+template <class _Rp>
+promise<_Rp>::~promise() {
+ if (__state_) {
+ if (!__state_->__has_value() && __state_->use_count() > 1)
+ __state_->set_exception(make_exception_ptr(future_error(make_error_code(future_errc::broken_promise))));
+ __state_->__release_shared();
+ }
+}
+
+template <class _Rp>
+future<_Rp> promise<_Rp>::get_future() {
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ return future<_Rp>(__state_);
+}
+
+template <class _Rp>
+void promise<_Rp>::set_value(const _Rp& __r) {
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_value(__r);
+}
+
+template <class _Rp>
+void promise<_Rp>::set_value(_Rp&& __r) {
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_value(std::move(__r));
+}
+
+template <class _Rp>
+void promise<_Rp>::set_exception(exception_ptr __p) {
+ _LIBCPP_ASSERT_NON_NULL(__p != nullptr, "promise::set_exception: received nullptr");
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_exception(__p);
+}
+
+template <class _Rp>
+void promise<_Rp>::set_value_at_thread_exit(const _Rp& __r) {
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_value_at_thread_exit(__r);
+}
+
+template <class _Rp>
+void promise<_Rp>::set_value_at_thread_exit(_Rp&& __r) {
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_value_at_thread_exit(std::move(__r));
+}
+
+template <class _Rp>
+void promise<_Rp>::set_exception_at_thread_exit(exception_ptr __p) {
+ _LIBCPP_ASSERT_NON_NULL(__p != nullptr, "promise::set_exception_at_thread_exit: received nullptr");
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_exception_at_thread_exit(__p);
+}
+
+// promise<R&>
+
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS promise<_Rp&> {
+ __assoc_state<_Rp&>* __state_;
+
+ _LIBCPP_HIDE_FROM_ABI explicit promise(nullptr_t) _NOEXCEPT : __state_(nullptr) {}
+
+ template <class>
+ friend class packaged_task;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI promise();
+ template <class _Allocator>
+ _LIBCPP_HIDE_FROM_ABI promise(allocator_arg_t, const _Allocator& __a);
+ _LIBCPP_HIDE_FROM_ABI promise(promise&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) { __rhs.__state_ = nullptr; }
+ promise(const promise& __rhs) = delete;
+ _LIBCPP_HIDE_FROM_ABI ~promise();
+
+ // assignment
+ _LIBCPP_HIDE_FROM_ABI promise& operator=(promise&& __rhs) _NOEXCEPT {
+ promise(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+ promise& operator=(const promise& __rhs) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(promise& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // retrieving the result
+ _LIBCPP_HIDE_FROM_ABI future<_Rp&> get_future();
+
+ // setting the result
+ _LIBCPP_HIDE_FROM_ABI void set_value(_Rp& __r);
+ _LIBCPP_HIDE_FROM_ABI void set_exception(exception_ptr __p);
+
+ // setting the result with deferred notification
+ _LIBCPP_HIDE_FROM_ABI void set_value_at_thread_exit(_Rp&);
+ _LIBCPP_HIDE_FROM_ABI void set_exception_at_thread_exit(exception_ptr __p);
+};
+
+template <class _Rp>
+promise<_Rp&>::promise() : __state_(new __assoc_state<_Rp&>) {}
+
+template <class _Rp>
+template <class _Alloc>
+promise<_Rp&>::promise(allocator_arg_t, const _Alloc& __a0) {
+ typedef __assoc_state_alloc<_Rp&, _Alloc> _State;
+ typedef typename __allocator_traits_rebind<_Alloc, _State>::type _A2;
+ typedef __allocator_destructor<_A2> _D2;
+ _A2 __a(__a0);
+ unique_ptr<_State, _D2> __hold(__a.allocate(1), _D2(__a, 1));
+ ::new ((void*)std::addressof(*__hold.get())) _State(__a0);
+ __state_ = std::addressof(*__hold.release());
+}
+
+template <class _Rp>
+promise<_Rp&>::~promise() {
+ if (__state_) {
+ if (!__state_->__has_value() && __state_->use_count() > 1)
+ __state_->set_exception(make_exception_ptr(future_error(make_error_code(future_errc::broken_promise))));
+ __state_->__release_shared();
+ }
+}
+
+template <class _Rp>
+future<_Rp&> promise<_Rp&>::get_future() {
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ return future<_Rp&>(__state_);
+}
+
+template <class _Rp>
+void promise<_Rp&>::set_value(_Rp& __r) {
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_value(__r);
+}
+
+template <class _Rp>
+void promise<_Rp&>::set_exception(exception_ptr __p) {
+ _LIBCPP_ASSERT_NON_NULL(__p != nullptr, "promise::set_exception: received nullptr");
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_exception(__p);
+}
+
+template <class _Rp>
+void promise<_Rp&>::set_value_at_thread_exit(_Rp& __r) {
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_value_at_thread_exit(__r);
+}
+
+template <class _Rp>
+void promise<_Rp&>::set_exception_at_thread_exit(exception_ptr __p) {
+ _LIBCPP_ASSERT_NON_NULL(__p != nullptr, "promise::set_exception_at_thread_exit: received nullptr");
+ if (__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ __state_->set_exception_at_thread_exit(__p);
+}
+
+// promise<void>
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI promise<void> {
+ __assoc_sub_state* __state_;
+
+ _LIBCPP_HIDE_FROM_ABI explicit promise(nullptr_t) _NOEXCEPT : __state_(nullptr) {}
+
+ template <class>
+ friend class packaged_task;
+
+public:
+ promise();
+ template <class _Allocator>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS promise(allocator_arg_t, const _Allocator& __a);
+ _LIBCPP_HIDE_FROM_ABI promise(promise&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) { __rhs.__state_ = nullptr; }
+ promise(const promise& __rhs) = delete;
+ ~promise();
+
+ // assignment
+ _LIBCPP_HIDE_FROM_ABI promise& operator=(promise&& __rhs) _NOEXCEPT {
+ promise(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+ promise& operator=(const promise& __rhs) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(promise& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // retrieving the result
+ future<void> get_future();
+
+ // setting the result
+ void set_value();
+ void set_exception(exception_ptr __p);
+
+ // setting the result with deferred notification
+ void set_value_at_thread_exit();
+ void set_exception_at_thread_exit(exception_ptr __p);
+};
+
+template <class _Alloc>
+promise<void>::promise(allocator_arg_t, const _Alloc& __a0) {
+ typedef __assoc_sub_state_alloc<_Alloc> _State;
+ typedef typename __allocator_traits_rebind<_Alloc, _State>::type _A2;
+ typedef __allocator_destructor<_A2> _D2;
+ _A2 __a(__a0);
+ unique_ptr<_State, _D2> __hold(__a.allocate(1), _D2(__a, 1));
+ ::new ((void*)std::addressof(*__hold.get())) _State(__a0);
+ __state_ = std::addressof(*__hold.release());
+}
+
+template <class _Rp>
+inline _LIBCPP_HIDE_FROM_ABI void swap(promise<_Rp>& __x, promise<_Rp>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+template <class _Rp, class _Alloc>
+struct _LIBCPP_TEMPLATE_VIS uses_allocator<promise<_Rp>, _Alloc> : public true_type {};
+
+// packaged_task
+
+template <class _Fp>
+class __packaged_task_base;
+
+template <class _Rp, class... _ArgTypes>
+class __packaged_task_base<_Rp(_ArgTypes...)> {
+public:
+ _LIBCPP_HIDE_FROM_ABI __packaged_task_base() {}
+ __packaged_task_base(const __packaged_task_base&) = delete;
+ __packaged_task_base& operator=(const __packaged_task_base&) = delete;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ virtual ~__packaged_task_base() {}
+ virtual void __move_to(__packaged_task_base*) _NOEXCEPT = 0;
+ virtual void destroy() = 0;
+ virtual void destroy_deallocate() = 0;
+ virtual _Rp operator()(_ArgTypes&&...) = 0;
+};
+
+template <class _FD, class _Alloc, class _FB>
+class __packaged_task_func;
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+class __packaged_task_func<_Fp, _Alloc, _Rp(_ArgTypes...)> : public __packaged_task_base<_Rp(_ArgTypes...)> {
+ __compressed_pair<_Fp, _Alloc> __f_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __packaged_task_func(const _Fp& __f) : __f_(__f, __default_init_tag()) {}
+ _LIBCPP_HIDE_FROM_ABI explicit __packaged_task_func(_Fp&& __f) : __f_(std::move(__f), __default_init_tag()) {}
+ _LIBCPP_HIDE_FROM_ABI __packaged_task_func(const _Fp& __f, const _Alloc& __a) : __f_(__f, __a) {}
+ _LIBCPP_HIDE_FROM_ABI __packaged_task_func(_Fp&& __f, const _Alloc& __a) : __f_(std::move(__f), __a) {}
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __move_to(__packaged_task_base<_Rp(_ArgTypes...)>*) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void destroy();
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void destroy_deallocate();
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual _Rp operator()(_ArgTypes&&... __args);
+};
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+void __packaged_task_func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__move_to(
+ __packaged_task_base<_Rp(_ArgTypes...)>* __p) _NOEXCEPT {
+ ::new ((void*)__p) __packaged_task_func(std::move(__f_.first()), std::move(__f_.second()));
+}
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+void __packaged_task_func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy() {
+ __f_.~__compressed_pair<_Fp, _Alloc>();
+}
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+void __packaged_task_func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy_deallocate() {
+ typedef typename __allocator_traits_rebind<_Alloc, __packaged_task_func>::type _Ap;
+ typedef allocator_traits<_Ap> _ATraits;
+ typedef pointer_traits<typename _ATraits::pointer> _PTraits;
+ _Ap __a(__f_.second());
+ __f_.~__compressed_pair<_Fp, _Alloc>();
+ __a.deallocate(_PTraits::pointer_to(*this), 1);
+}
+
+template <class _Fp, class _Alloc, class _Rp, class... _ArgTypes>
+_Rp __packaged_task_func<_Fp, _Alloc, _Rp(_ArgTypes...)>::operator()(_ArgTypes&&... __arg) {
+ return std::__invoke(__f_.first(), std::forward<_ArgTypes>(__arg)...);
+}
+
+template <class _Callable>
+class __packaged_task_function;
+
+template <class _Rp, class... _ArgTypes>
+class __packaged_task_function<_Rp(_ArgTypes...)> {
+ typedef __packaged_task_base<_Rp(_ArgTypes...)> __base;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_CFI __base* __get_buf() { return (__base*)&__buf_; }
+
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ typename aligned_storage<3 * sizeof(void*)>::type __buf_;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ __base* __f_;
+
+public:
+ typedef _Rp result_type;
+
+ // construct/copy/destroy:
+ _LIBCPP_HIDE_FROM_ABI __packaged_task_function() _NOEXCEPT : __f_(nullptr) {}
+ template <class _Fp>
+ _LIBCPP_HIDE_FROM_ABI __packaged_task_function(_Fp&& __f);
+ template <class _Fp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI __packaged_task_function(allocator_arg_t, const _Alloc& __a, _Fp&& __f);
+
+ _LIBCPP_HIDE_FROM_ABI __packaged_task_function(__packaged_task_function&&) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI __packaged_task_function& operator=(__packaged_task_function&&) _NOEXCEPT;
+
+ __packaged_task_function(const __packaged_task_function&) = delete;
+ __packaged_task_function& operator=(const __packaged_task_function&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI ~__packaged_task_function();
+
+ _LIBCPP_HIDE_FROM_ABI void swap(__packaged_task_function&) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDE_FROM_ABI _Rp operator()(_ArgTypes...) const;
+};
+
+template <class _Rp, class... _ArgTypes>
+__packaged_task_function<_Rp(_ArgTypes...)>::__packaged_task_function(__packaged_task_function&& __f) _NOEXCEPT {
+ if (__f.__f_ == nullptr)
+ __f_ = nullptr;
+ else if (__f.__f_ == __f.__get_buf()) {
+ __f.__f_->__move_to(__get_buf());
+ __f_ = (__base*)&__buf_;
+ } else {
+ __f_ = __f.__f_;
+ __f.__f_ = nullptr;
+ }
+}
+
+template <class _Rp, class... _ArgTypes>
+template <class _Fp>
+__packaged_task_function<_Rp(_ArgTypes...)>::__packaged_task_function(_Fp&& __f) : __f_(nullptr) {
+ typedef __libcpp_remove_reference_t<__decay_t<_Fp> > _FR;
+ typedef __packaged_task_func<_FR, allocator<_FR>, _Rp(_ArgTypes...)> _FF;
+ if (sizeof(_FF) <= sizeof(__buf_)) {
+ ::new ((void*)&__buf_) _FF(std::forward<_Fp>(__f));
+ __f_ = (__base*)&__buf_;
+ } else {
+ typedef allocator<_FF> _Ap;
+ _Ap __a;
+ typedef __allocator_destructor<_Ap> _Dp;
+ unique_ptr<__base, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
+ ::new ((void*)__hold.get()) _FF(std::forward<_Fp>(__f), allocator<_FR>(__a));
+ __f_ = __hold.release();
+ }
+}
+
+template <class _Rp, class... _ArgTypes>
+template <class _Fp, class _Alloc>
+__packaged_task_function<_Rp(_ArgTypes...)>::__packaged_task_function(allocator_arg_t, const _Alloc& __a0, _Fp&& __f)
+ : __f_(nullptr) {
+ typedef __libcpp_remove_reference_t<__decay_t<_Fp> > _FR;
+ typedef __packaged_task_func<_FR, _Alloc, _Rp(_ArgTypes...)> _FF;
+ if (sizeof(_FF) <= sizeof(__buf_)) {
+ __f_ = (__base*)&__buf_;
+ ::new ((void*)__f_) _FF(std::forward<_Fp>(__f));
+ } else {
+ typedef typename __allocator_traits_rebind<_Alloc, _FF>::type _Ap;
+ _Ap __a(__a0);
+ typedef __allocator_destructor<_Ap> _Dp;
+ unique_ptr<__base, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
+ ::new ((void*)std::addressof(*__hold.get())) _FF(std::forward<_Fp>(__f), _Alloc(__a));
+ __f_ = std::addressof(*__hold.release());
+ }
+}
+
+template <class _Rp, class... _ArgTypes>
+__packaged_task_function<_Rp(_ArgTypes...)>&
+__packaged_task_function<_Rp(_ArgTypes...)>::operator=(__packaged_task_function&& __f) _NOEXCEPT {
+ if (__f_ == __get_buf())
+ __f_->destroy();
+ else if (__f_)
+ __f_->destroy_deallocate();
+ __f_ = nullptr;
+ if (__f.__f_ == nullptr)
+ __f_ = nullptr;
+ else if (__f.__f_ == __f.__get_buf()) {
+ __f.__f_->__move_to(__get_buf());
+ __f_ = __get_buf();
+ } else {
+ __f_ = __f.__f_;
+ __f.__f_ = nullptr;
+ }
+ return *this;
+}
+
+template <class _Rp, class... _ArgTypes>
+__packaged_task_function<_Rp(_ArgTypes...)>::~__packaged_task_function() {
+ if (__f_ == __get_buf())
+ __f_->destroy();
+ else if (__f_)
+ __f_->destroy_deallocate();
+}
+
+template <class _Rp, class... _ArgTypes>
+_LIBCPP_NO_CFI void __packaged_task_function<_Rp(_ArgTypes...)>::swap(__packaged_task_function& __f) _NOEXCEPT {
+ if (__f_ == (__base*)&__buf_ && __f.__f_ == (__base*)&__f.__buf_) {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ __base* __t = (__base*)&__tempbuf;
+ __f_->__move_to(__t);
+ __f_->destroy();
+ __f_ = nullptr;
+ __f.__f_->__move_to((__base*)&__buf_);
+ __f.__f_->destroy();
+ __f.__f_ = nullptr;
+ __f_ = (__base*)&__buf_;
+ __t->__move_to((__base*)&__f.__buf_);
+ __t->destroy();
+ __f.__f_ = (__base*)&__f.__buf_;
+ } else if (__f_ == (__base*)&__buf_) {
+ __f_->__move_to((__base*)&__f.__buf_);
+ __f_->destroy();
+ __f_ = __f.__f_;
+ __f.__f_ = (__base*)&__f.__buf_;
+ } else if (__f.__f_ == (__base*)&__f.__buf_) {
+ __f.__f_->__move_to((__base*)&__buf_);
+ __f.__f_->destroy();
+ __f.__f_ = __f_;
+ __f_ = (__base*)&__buf_;
+ } else
+ std::swap(__f_, __f.__f_);
+}
+
+template <class _Rp, class... _ArgTypes>
+inline _Rp __packaged_task_function<_Rp(_ArgTypes...)>::operator()(_ArgTypes... __arg) const {
+ return (*__f_)(std::forward<_ArgTypes>(__arg)...);
+}
+
+template <class _Rp, class... _ArgTypes>
+class _LIBCPP_TEMPLATE_VIS packaged_task<_Rp(_ArgTypes...)> {
+public:
+ typedef _Rp result_type; // extension
+
+private:
+ __packaged_task_function<result_type(_ArgTypes...)> __f_;
+ promise<result_type> __p_;
+
+public:
+ // construction and destruction
+ _LIBCPP_HIDE_FROM_ABI packaged_task() _NOEXCEPT : __p_(nullptr) {}
+
+ template <class _Fp, __enable_if_t<!is_same<__remove_cvref_t<_Fp>, packaged_task>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit packaged_task(_Fp&& __f) : __f_(std::forward<_Fp>(__f)) {}
+
+ template <class _Fp, class _Allocator, __enable_if_t<!is_same<__remove_cvref_t<_Fp>, packaged_task>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI packaged_task(allocator_arg_t, const _Allocator& __a, _Fp&& __f)
+ : __f_(allocator_arg_t(), __a, std::forward<_Fp>(__f)), __p_(allocator_arg_t(), __a) {}
+ // ~packaged_task() = default;
+
+ // no copy
+ packaged_task(const packaged_task&) = delete;
+ packaged_task& operator=(const packaged_task&) = delete;
+
+ // move support
+ _LIBCPP_HIDE_FROM_ABI packaged_task(packaged_task&& __other) _NOEXCEPT
+ : __f_(std::move(__other.__f_)),
+ __p_(std::move(__other.__p_)) {}
+ _LIBCPP_HIDE_FROM_ABI packaged_task& operator=(packaged_task&& __other) _NOEXCEPT {
+ __f_ = std::move(__other.__f_);
+ __p_ = std::move(__other.__p_);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI void swap(packaged_task& __other) _NOEXCEPT {
+ __f_.swap(__other.__f_);
+ __p_.swap(__other.__p_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool valid() const _NOEXCEPT { return __p_.__state_ != nullptr; }
+
+ // result retrieval
+ _LIBCPP_HIDE_FROM_ABI future<result_type> get_future() { return __p_.get_future(); }
+
+ // execution
+ _LIBCPP_HIDE_FROM_ABI void operator()(_ArgTypes... __args);
+ _LIBCPP_HIDE_FROM_ABI void make_ready_at_thread_exit(_ArgTypes... __args);
+
+ _LIBCPP_HIDE_FROM_ABI void reset();
+};
+
+template <class _Rp, class... _ArgTypes>
+void packaged_task<_Rp(_ArgTypes...)>::operator()(_ArgTypes... __args) {
+ if (__p_.__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ if (__p_.__state_->__has_value())
+ __throw_future_error(future_errc::promise_already_satisfied);
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __p_.set_value(__f_(std::forward<_ArgTypes>(__args)...));
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __p_.set_exception(current_exception());
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class _Rp, class... _ArgTypes>
+void packaged_task<_Rp(_ArgTypes...)>::make_ready_at_thread_exit(_ArgTypes... __args) {
+ if (__p_.__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ if (__p_.__state_->__has_value())
+ __throw_future_error(future_errc::promise_already_satisfied);
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __p_.set_value_at_thread_exit(__f_(std::forward<_ArgTypes>(__args)...));
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __p_.set_exception_at_thread_exit(current_exception());
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class _Rp, class... _ArgTypes>
+void packaged_task<_Rp(_ArgTypes...)>::reset() {
+ if (!valid())
+ __throw_future_error(future_errc::no_state);
+ __p_ = promise<result_type>();
+}
+
+template <class... _ArgTypes>
+class _LIBCPP_TEMPLATE_VIS packaged_task<void(_ArgTypes...)> {
+public:
+ typedef void result_type; // extension
+
+private:
+ __packaged_task_function<result_type(_ArgTypes...)> __f_;
+ promise<result_type> __p_;
+
+public:
+ // construction and destruction
+ _LIBCPP_HIDE_FROM_ABI packaged_task() _NOEXCEPT : __p_(nullptr) {}
+ template <class _Fp, __enable_if_t<!is_same<__remove_cvref_t<_Fp>, packaged_task>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit packaged_task(_Fp&& __f) : __f_(std::forward<_Fp>(__f)) {}
+ template <class _Fp, class _Allocator, __enable_if_t<!is_same<__remove_cvref_t<_Fp>, packaged_task>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI packaged_task(allocator_arg_t, const _Allocator& __a, _Fp&& __f)
+ : __f_(allocator_arg_t(), __a, std::forward<_Fp>(__f)), __p_(allocator_arg_t(), __a) {}
+ // ~packaged_task() = default;
+
+ // no copy
+ packaged_task(const packaged_task&) = delete;
+ packaged_task& operator=(const packaged_task&) = delete;
+
+ // move support
+ _LIBCPP_HIDE_FROM_ABI packaged_task(packaged_task&& __other) _NOEXCEPT
+ : __f_(std::move(__other.__f_)),
+ __p_(std::move(__other.__p_)) {}
+ _LIBCPP_HIDE_FROM_ABI packaged_task& operator=(packaged_task&& __other) _NOEXCEPT {
+ __f_ = std::move(__other.__f_);
+ __p_ = std::move(__other.__p_);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI void swap(packaged_task& __other) _NOEXCEPT {
+ __f_.swap(__other.__f_);
+ __p_.swap(__other.__p_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool valid() const _NOEXCEPT { return __p_.__state_ != nullptr; }
+
+ // result retrieval
+ _LIBCPP_HIDE_FROM_ABI future<result_type> get_future() { return __p_.get_future(); }
+
+ // execution
+ _LIBCPP_HIDE_FROM_ABI void operator()(_ArgTypes... __args);
+ _LIBCPP_HIDE_FROM_ABI void make_ready_at_thread_exit(_ArgTypes... __args);
+
+ _LIBCPP_HIDE_FROM_ABI void reset();
+};
+
+# if _LIBCPP_STD_VER >= 17
+
+template <class _Rp, class... _Args>
+packaged_task(_Rp (*)(_Args...)) -> packaged_task<_Rp(_Args...)>;
+
+template <class _Fp, class _Stripped = typename __strip_signature<decltype(&_Fp::operator())>::type>
+packaged_task(_Fp) -> packaged_task<_Stripped>;
+
+# endif
+
+template <class... _ArgTypes>
+void packaged_task<void(_ArgTypes...)>::operator()(_ArgTypes... __args) {
+ if (__p_.__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ if (__p_.__state_->__has_value())
+ __throw_future_error(future_errc::promise_already_satisfied);
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __f_(std::forward<_ArgTypes>(__args)...);
+ __p_.set_value();
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __p_.set_exception(current_exception());
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class... _ArgTypes>
+void packaged_task<void(_ArgTypes...)>::make_ready_at_thread_exit(_ArgTypes... __args) {
+ if (__p_.__state_ == nullptr)
+ __throw_future_error(future_errc::no_state);
+ if (__p_.__state_->__has_value())
+ __throw_future_error(future_errc::promise_already_satisfied);
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __f_(std::forward<_ArgTypes>(__args)...);
+ __p_.set_value_at_thread_exit();
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __p_.set_exception_at_thread_exit(current_exception());
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class... _ArgTypes>
+void packaged_task<void(_ArgTypes...)>::reset() {
+ if (!valid())
+ __throw_future_error(future_errc::no_state);
+ __p_ = promise<result_type>();
+}
+
+template <class _Rp, class... _ArgTypes>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(packaged_task<_Rp(_ArgTypes...)>& __x, packaged_task<_Rp(_ArgTypes...)>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+template <class _Callable, class _Alloc>
+struct _LIBCPP_TEMPLATE_VIS uses_allocator<packaged_task<_Callable>, _Alloc> : public true_type {};
+
+template <class _Rp, class _Fp>
+_LIBCPP_HIDE_FROM_ABI future<_Rp> __make_deferred_assoc_state(_Fp&& __f) {
+ unique_ptr<__deferred_assoc_state<_Rp, _Fp>, __release_shared_count> __h(
+ new __deferred_assoc_state<_Rp, _Fp>(std::forward<_Fp>(__f)));
+ return future<_Rp>(__h.get());
+}
+
+template <class _Rp, class _Fp>
+_LIBCPP_HIDE_FROM_ABI future<_Rp> __make_async_assoc_state(_Fp&& __f) {
+ unique_ptr<__async_assoc_state<_Rp, _Fp>, __release_shared_count> __h(
+ new __async_assoc_state<_Rp, _Fp>(std::forward<_Fp>(__f)));
+ std::thread(&__async_assoc_state<_Rp, _Fp>::__execute, __h.get()).detach();
+ return future<_Rp>(__h.get());
+}
+
+# ifndef _LIBCPP_CXX03_LANG
+
+template <class _Fp, class... _Args>
+class _LIBCPP_HIDDEN __async_func {
+ tuple<_Fp, _Args...> __f_;
+
+public:
+ typedef typename __invoke_of<_Fp, _Args...>::type _Rp;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __async_func(_Fp&& __f, _Args&&... __args)
+ : __f_(std::move(__f), std::move(__args)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI __async_func(__async_func&& __f) : __f_(std::move(__f.__f_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Rp operator()() {
+ typedef typename __make_tuple_indices<1 + sizeof...(_Args), 1>::type _Index;
+ return __execute(_Index());
+ }
+
+private:
+ template <size_t... _Indices>
+ _LIBCPP_HIDE_FROM_ABI _Rp __execute(__tuple_indices<_Indices...>) {
+ return std::__invoke(std::move(std::get<0>(__f_)), std::move(std::get<_Indices>(__f_))...);
+ }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI bool __does_policy_contain(launch __policy, launch __value) {
+ return (int(__policy) & int(__value)) != 0;
+}
+
+template <class _Fp, class... _Args>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI future<typename __invoke_of<__decay_t<_Fp>, __decay_t<_Args>...>::type>
+async(launch __policy, _Fp&& __f, _Args&&... __args) {
+ typedef __async_func<__decay_t<_Fp>, __decay_t<_Args>...> _BF;
+ typedef typename _BF::_Rp _Rp;
+
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+ if (__does_policy_contain(__policy, launch::async))
+ return std::__make_async_assoc_state<_Rp>(
+ _BF(_LIBCPP_AUTO_CAST(std::forward<_Fp>(__f)), _LIBCPP_AUTO_CAST(std::forward<_Args>(__args))...));
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ if (__policy == launch::async)
+ throw;
+ }
+# endif
+
+ if (__does_policy_contain(__policy, launch::deferred))
+ return std::__make_deferred_assoc_state<_Rp>(
+ _BF(_LIBCPP_AUTO_CAST(std::forward<_Fp>(__f)), _LIBCPP_AUTO_CAST(std::forward<_Args>(__args))...));
+ return future<_Rp>{};
+}
+
+template <class _Fp, class... _Args>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI future<typename __invoke_of<__decay_t<_Fp>, __decay_t<_Args>...>::type>
+async(_Fp&& __f, _Args&&... __args) {
+ return std::async(launch::any, std::forward<_Fp>(__f), std::forward<_Args>(__args)...);
+}
+
+# endif // C++03
+
+// shared_future
+
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS shared_future {
+ __assoc_state<_Rp>* __state_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI shared_future() _NOEXCEPT : __state_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI shared_future(const shared_future& __rhs) _NOEXCEPT : __state_(__rhs.__state_) {
+ if (__state_)
+ __state_->__add_shared();
+ }
+ _LIBCPP_HIDE_FROM_ABI shared_future(future<_Rp>&& __f) _NOEXCEPT : __state_(__f.__state_) { __f.__state_ = nullptr; }
+ _LIBCPP_HIDE_FROM_ABI shared_future(shared_future&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) {
+ __rhs.__state_ = nullptr;
+ }
+ _LIBCPP_HIDE_FROM_ABI ~shared_future();
+ _LIBCPP_HIDE_FROM_ABI shared_future& operator=(const shared_future& __rhs) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI shared_future& operator=(shared_future&& __rhs) _NOEXCEPT {
+ shared_future(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ // retrieving the value
+ _LIBCPP_HIDE_FROM_ABI const _Rp& get() const { return __state_->copy(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(shared_future& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // functions to check state
+ _LIBCPP_HIDE_FROM_ABI bool valid() const _NOEXCEPT { return __state_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void wait() const { __state_->wait(); }
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const {
+ return __state_->wait_for(__rel_time);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const {
+ return __state_->wait_until(__abs_time);
+ }
+};
+
+template <class _Rp>
+shared_future<_Rp>::~shared_future() {
+ if (__state_)
+ __state_->__release_shared();
+}
+
+template <class _Rp>
+shared_future<_Rp>& shared_future<_Rp>::operator=(const shared_future& __rhs) _NOEXCEPT {
+ if (__rhs.__state_)
+ __rhs.__state_->__add_shared();
+ if (__state_)
+ __state_->__release_shared();
+ __state_ = __rhs.__state_;
+ return *this;
+}
+
+template <class _Rp>
+class _LIBCPP_TEMPLATE_VIS shared_future<_Rp&> {
+ __assoc_state<_Rp&>* __state_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI shared_future() _NOEXCEPT : __state_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI shared_future(const shared_future& __rhs) : __state_(__rhs.__state_) {
+ if (__state_)
+ __state_->__add_shared();
+ }
+ _LIBCPP_HIDE_FROM_ABI shared_future(future<_Rp&>&& __f) _NOEXCEPT : __state_(__f.__state_) { __f.__state_ = nullptr; }
+ _LIBCPP_HIDE_FROM_ABI shared_future(shared_future&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) {
+ __rhs.__state_ = nullptr;
+ }
+ _LIBCPP_HIDE_FROM_ABI ~shared_future();
+ _LIBCPP_HIDE_FROM_ABI shared_future& operator=(const shared_future& __rhs);
+ _LIBCPP_HIDE_FROM_ABI shared_future& operator=(shared_future&& __rhs) _NOEXCEPT {
+ shared_future(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ // retrieving the value
+ _LIBCPP_HIDE_FROM_ABI _Rp& get() const { return __state_->copy(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(shared_future& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // functions to check state
+ _LIBCPP_HIDE_FROM_ABI bool valid() const _NOEXCEPT { return __state_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void wait() const { __state_->wait(); }
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const {
+ return __state_->wait_for(__rel_time);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const {
+ return __state_->wait_until(__abs_time);
+ }
+};
+
+template <class _Rp>
+shared_future<_Rp&>::~shared_future() {
+ if (__state_)
+ __state_->__release_shared();
+}
+
+template <class _Rp>
+shared_future<_Rp&>& shared_future<_Rp&>::operator=(const shared_future& __rhs) {
+ if (__rhs.__state_)
+ __rhs.__state_->__add_shared();
+ if (__state_)
+ __state_->__release_shared();
+ __state_ = __rhs.__state_;
+ return *this;
+}
+
+template <>
+class _LIBCPP_EXPORTED_FROM_ABI shared_future<void> {
+ __assoc_sub_state* __state_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI shared_future() _NOEXCEPT : __state_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI shared_future(const shared_future& __rhs) : __state_(__rhs.__state_) {
+ if (__state_)
+ __state_->__add_shared();
+ }
+ _LIBCPP_HIDE_FROM_ABI shared_future(future<void>&& __f) _NOEXCEPT : __state_(__f.__state_) { __f.__state_ = nullptr; }
+ _LIBCPP_HIDE_FROM_ABI shared_future(shared_future&& __rhs) _NOEXCEPT : __state_(__rhs.__state_) {
+ __rhs.__state_ = nullptr;
+ }
+ ~shared_future();
+ shared_future& operator=(const shared_future& __rhs);
+ _LIBCPP_HIDE_FROM_ABI shared_future& operator=(shared_future&& __rhs) _NOEXCEPT {
+ shared_future(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ // retrieving the value
+ _LIBCPP_HIDE_FROM_ABI void get() const { __state_->copy(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(shared_future& __rhs) _NOEXCEPT { std::swap(__state_, __rhs.__state_); }
+
+ // functions to check state
+ _LIBCPP_HIDE_FROM_ABI bool valid() const _NOEXCEPT { return __state_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI void wait() const { __state_->wait(); }
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const {
+ return __state_->wait_for(__rel_time);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_HIDE_FROM_ABI future_status wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const {
+ return __state_->wait_until(__abs_time);
+ }
+};
+
+template <class _Rp>
+inline _LIBCPP_HIDE_FROM_ABI void swap(shared_future<_Rp>& __x, shared_future<_Rp>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+template <class _Rp>
+inline shared_future<_Rp> future<_Rp>::share() _NOEXCEPT {
+ return shared_future<_Rp>(std::move(*this));
+}
+
+template <class _Rp>
+inline shared_future<_Rp&> future<_Rp&>::share() _NOEXCEPT {
+ return shared_future<_Rp&>(std::move(*this));
+}
+
+inline shared_future<void> future<void>::share() _NOEXCEPT { return shared_future<void>(std::move(*this)); }
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_THREADS)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <chrono>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <cstdlib>
+# include <exception>
+# include <iosfwd>
+# include <system_error>
+#endif
+
+#endif // _LIBCPP_FUTURE
diff --git a/libcxx/include/__cxx03/initializer_list b/libcxx/include/__cxx03/initializer_list
new file mode 100644
index 00000000000000..680ca1cd20d550
--- /dev/null
+++ b/libcxx/include/__cxx03/initializer_list
@@ -0,0 +1,98 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_INITIALIZER_LIST
+#define _LIBCPP_INITIALIZER_LIST
+
+/*
+ initializer_list synopsis
+
+namespace std
+{
+
+template<class E>
+class initializer_list
+{
+public:
+ typedef E value_type;
+ typedef const E& reference;
+ typedef const E& const_reference;
+ typedef size_t size_type;
+
+ typedef const E* iterator;
+ typedef const E* const_iterator;
+
+ initializer_list() noexcept; // constexpr in C++14
+
+ size_t size() const noexcept; // constexpr in C++14
+ const E* begin() const noexcept; // constexpr in C++14
+ const E* end() const noexcept; // constexpr in C++14
+};
+
+template<class E> const E* begin(initializer_list<E> il) noexcept; // constexpr in C++14
+template<class E> const E* end(initializer_list<E> il) noexcept; // constexpr in C++14
+
+} // std
+
+*/
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+namespace std // purposefully not versioned
+{
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Ep>
+class _LIBCPP_TEMPLATE_VIS initializer_list {
+ const _Ep* __begin_;
+ size_t __size_;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 initializer_list(const _Ep* __b, size_t __s) _NOEXCEPT
+ : __begin_(__b),
+ __size_(__s) {}
+
+public:
+ typedef _Ep value_type;
+ typedef const _Ep& reference;
+ typedef const _Ep& const_reference;
+ typedef size_t size_type;
+
+ typedef const _Ep* iterator;
+ typedef const _Ep* const_iterator;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 initializer_list() _NOEXCEPT : __begin_(nullptr), __size_(0) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 size_t size() const _NOEXCEPT { return __size_; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Ep* begin() const _NOEXCEPT { return __begin_; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Ep* end() const _NOEXCEPT { return __begin_ + __size_; }
+};
+
+template <class _Ep>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Ep* begin(initializer_list<_Ep> __il) _NOEXCEPT {
+ return __il.begin();
+}
+
+template <class _Ep>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Ep* end(initializer_list<_Ep> __il) _NOEXCEPT {
+ return __il.end();
+}
+
+#endif // !defined(_LIBCPP_CXX03_LANG)
+
+} // namespace std
+
+#endif // _LIBCPP_INITIALIZER_LIST
diff --git a/libcxx/include/__cxx03/inttypes.h b/libcxx/include/__cxx03/inttypes.h
new file mode 100644
index 00000000000000..8664412bd52ffc
--- /dev/null
+++ b/libcxx/include/__cxx03/inttypes.h
@@ -0,0 +1,264 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_INTTYPES_H
+// AIX system headers need inttypes.h to be re-enterable while _STD_TYPES_T
+// is defined until an inclusion of it without _STD_TYPES_T occurs, in which
+// case the header guard macro is defined.
+#if !defined(_AIX) || !defined(_STD_TYPES_T)
+# define _LIBCPP_INTTYPES_H
+#endif // _STD_TYPES_T
+
+/*
+ inttypes.h synopsis
+
+This entire header is C99 / C++0X
+
+#include <stdint.h> // <cinttypes> includes <cstdint>
+
+Macros:
+
+ PRId8
+ PRId16
+ PRId32
+ PRId64
+
+ PRIdLEAST8
+ PRIdLEAST16
+ PRIdLEAST32
+ PRIdLEAST64
+
+ PRIdFAST8
+ PRIdFAST16
+ PRIdFAST32
+ PRIdFAST64
+
+ PRIdMAX
+ PRIdPTR
+
+ PRIi8
+ PRIi16
+ PRIi32
+ PRIi64
+
+ PRIiLEAST8
+ PRIiLEAST16
+ PRIiLEAST32
+ PRIiLEAST64
+
+ PRIiFAST8
+ PRIiFAST16
+ PRIiFAST32
+ PRIiFAST64
+
+ PRIiMAX
+ PRIiPTR
+
+ PRIo8
+ PRIo16
+ PRIo32
+ PRIo64
+
+ PRIoLEAST8
+ PRIoLEAST16
+ PRIoLEAST32
+ PRIoLEAST64
+
+ PRIoFAST8
+ PRIoFAST16
+ PRIoFAST32
+ PRIoFAST64
+
+ PRIoMAX
+ PRIoPTR
+
+ PRIu8
+ PRIu16
+ PRIu32
+ PRIu64
+
+ PRIuLEAST8
+ PRIuLEAST16
+ PRIuLEAST32
+ PRIuLEAST64
+
+ PRIuFAST8
+ PRIuFAST16
+ PRIuFAST32
+ PRIuFAST64
+
+ PRIuMAX
+ PRIuPTR
+
+ PRIx8
+ PRIx16
+ PRIx32
+ PRIx64
+
+ PRIxLEAST8
+ PRIxLEAST16
+ PRIxLEAST32
+ PRIxLEAST64
+
+ PRIxFAST8
+ PRIxFAST16
+ PRIxFAST32
+ PRIxFAST64
+
+ PRIxMAX
+ PRIxPTR
+
+ PRIX8
+ PRIX16
+ PRIX32
+ PRIX64
+
+ PRIXLEAST8
+ PRIXLEAST16
+ PRIXLEAST32
+ PRIXLEAST64
+
+ PRIXFAST8
+ PRIXFAST16
+ PRIXFAST32
+ PRIXFAST64
+
+ PRIXMAX
+ PRIXPTR
+
+ SCNd8
+ SCNd16
+ SCNd32
+ SCNd64
+
+ SCNdLEAST8
+ SCNdLEAST16
+ SCNdLEAST32
+ SCNdLEAST64
+
+ SCNdFAST8
+ SCNdFAST16
+ SCNdFAST32
+ SCNdFAST64
+
+ SCNdMAX
+ SCNdPTR
+
+ SCNi8
+ SCNi16
+ SCNi32
+ SCNi64
+
+ SCNiLEAST8
+ SCNiLEAST16
+ SCNiLEAST32
+ SCNiLEAST64
+
+ SCNiFAST8
+ SCNiFAST16
+ SCNiFAST32
+ SCNiFAST64
+
+ SCNiMAX
+ SCNiPTR
+
+ SCNo8
+ SCNo16
+ SCNo32
+ SCNo64
+
+ SCNoLEAST8
+ SCNoLEAST16
+ SCNoLEAST32
+ SCNoLEAST64
+
+ SCNoFAST8
+ SCNoFAST16
+ SCNoFAST32
+ SCNoFAST64
+
+ SCNoMAX
+ SCNoPTR
+
+ SCNu8
+ SCNu16
+ SCNu32
+ SCNu64
+
+ SCNuLEAST8
+ SCNuLEAST16
+ SCNuLEAST32
+ SCNuLEAST64
+
+ SCNuFAST8
+ SCNuFAST16
+ SCNuFAST32
+ SCNuFAST64
+
+ SCNuMAX
+ SCNuPTR
+
+ SCNx8
+ SCNx16
+ SCNx32
+ SCNx64
+
+ SCNxLEAST8
+ SCNxLEAST16
+ SCNxLEAST32
+ SCNxLEAST64
+
+ SCNxFAST8
+ SCNxFAST16
+ SCNxFAST32
+ SCNxFAST64
+
+ SCNxMAX
+ SCNxPTR
+
+Types:
+
+ imaxdiv_t
+
+intmax_t imaxabs(intmax_t j);
+imaxdiv_t imaxdiv(intmax_t numer, intmax_t denom);
+intmax_t strtoimax(const char* restrict nptr, char** restrict endptr, int base);
+uintmax_t strtoumax(const char* restrict nptr, char** restrict endptr, int base);
+intmax_t wcstoimax(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base);
+uintmax_t wcstoumax(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base);
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+/* C99 stdlib (e.g. glibc < 2.18) does not provide format macros needed
+ for C++11 unless __STDC_FORMAT_MACROS is defined
+*/
+#if defined(__cplusplus) && !defined(__STDC_FORMAT_MACROS)
+# define __STDC_FORMAT_MACROS
+#endif
+
+#if __has_include_next(<inttypes.h>)
+# include_next <inttypes.h>
+#endif
+
+#ifdef __cplusplus
+
+# include <stdint.h>
+
+# undef imaxabs
+# undef imaxdiv
+
+#endif // __cplusplus
+
+#endif // _LIBCPP_INTTYPES_H
diff --git a/libcxx/include/__cxx03/iomanip b/libcxx/include/__cxx03/iomanip
new file mode 100644
index 00000000000000..fb4f15b9a58533
--- /dev/null
+++ b/libcxx/include/__cxx03/iomanip
@@ -0,0 +1,542 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_IOMANIP
+#define _LIBCPP_IOMANIP
+
+/*
+ iomanip synopsis
+
+namespace std {
+
+// types T1, T2, ... are unspecified implementation types
+T1 resetiosflags(ios_base::fmtflags mask);
+T2 setiosflags (ios_base::fmtflags mask);
+T3 setbase(int base);
+template<charT> T4 setfill(charT c);
+T5 setprecision(int n);
+T6 setw(int n);
+template <class moneyT> T7 get_money(moneyT& mon, bool intl = false);
+template <class charT, class moneyT> T8 put_money(const moneyT& mon, bool intl = false);
+template <class charT> T9 get_time(struct tm* tmb, const charT* fmt);
+template <class charT> T10 put_time(const struct tm* tmb, const charT* fmt);
+
+template <class charT>
+ T11 quoted(const charT* s, charT delim=charT('"'), charT escape=charT('\\')); // C++14
+
+template <class charT, class traits, class Allocator>
+ T12 quoted(const basic_string<charT, traits, Allocator>& s,
+ charT delim=charT('"'), charT escape=charT('\\')); // C++14
+
+template <class charT, class traits, class Allocator>
+ T13 quoted(basic_string<charT, traits, Allocator>& s,
+ charT delim=charT('"'), charT escape=charT('\\')); // C++14
+
+} // std
+
+*/
+
+#include <__config>
+#include <istream>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// resetiosflags
+
+class __iom_t1 {
+ ios_base::fmtflags __mask_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __iom_t1(ios_base::fmtflags __m) : __mask_(__m) {}
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t1& __x) {
+ __is.unsetf(__x.__mask_);
+ return __is;
+ }
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t1& __x) {
+ __os.unsetf(__x.__mask_);
+ return __os;
+ }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI __iom_t1 resetiosflags(ios_base::fmtflags __mask) { return __iom_t1(__mask); }
+
+// setiosflags
+
+class __iom_t2 {
+ ios_base::fmtflags __mask_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __iom_t2(ios_base::fmtflags __m) : __mask_(__m) {}
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t2& __x) {
+ __is.setf(__x.__mask_);
+ return __is;
+ }
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t2& __x) {
+ __os.setf(__x.__mask_);
+ return __os;
+ }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI __iom_t2 setiosflags(ios_base::fmtflags __mask) { return __iom_t2(__mask); }
+
+// setbase
+
+class __iom_t3 {
+ int __base_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __iom_t3(int __b) : __base_(__b) {}
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t3& __x) {
+ __is.setf(__x.__base_ == 8 ? ios_base::oct
+ : __x.__base_ == 10 ? ios_base::dec
+ : __x.__base_ == 16 ? ios_base::hex
+ : ios_base::fmtflags(0),
+ ios_base::basefield);
+ return __is;
+ }
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t3& __x) {
+ __os.setf(__x.__base_ == 8 ? ios_base::oct
+ : __x.__base_ == 10 ? ios_base::dec
+ : __x.__base_ == 16 ? ios_base::hex
+ : ios_base::fmtflags(0),
+ ios_base::basefield);
+ return __os;
+ }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI __iom_t3 setbase(int __base) { return __iom_t3(__base); }
+
+// setfill
+
+template <class _CharT>
+class __iom_t4 {
+ _CharT __fill_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __iom_t4(_CharT __c) : __fill_(__c) {}
+
+ template <class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t4& __x) {
+ __os.fill(__x.__fill_);
+ return __os;
+ }
+};
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI __iom_t4<_CharT> setfill(_CharT __c) {
+ return __iom_t4<_CharT>(__c);
+}
+
+// setprecision
+
+class __iom_t5 {
+ int __n_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __iom_t5(int __n) : __n_(__n) {}
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t5& __x) {
+ __is.precision(__x.__n_);
+ return __is;
+ }
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t5& __x) {
+ __os.precision(__x.__n_);
+ return __os;
+ }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI __iom_t5 setprecision(int __n) { return __iom_t5(__n); }
+
+// setw
+
+class __iom_t6 {
+ int __n_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __iom_t6(int __n) : __n_(__n) {}
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t6& __x) {
+ __is.width(__x.__n_);
+ return __is;
+ }
+
+ template <class _CharT, class _Traits>
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t6& __x) {
+ __os.width(__x.__n_);
+ return __os;
+ }
+};
+
+inline _LIBCPP_HIDE_FROM_ABI __iom_t6 setw(int __n) { return __iom_t6(__n); }
+
+// get_money
+
+template <class _MoneyT>
+class __iom_t7;
+
+template <class _CharT, class _Traits, class _MoneyT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t7<_MoneyT>& __x);
+
+template <class _MoneyT>
+class __iom_t7 {
+ _MoneyT& __mon_;
+ bool __intl_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __iom_t7(_MoneyT& __mon, bool __intl) : __mon_(__mon), __intl_(__intl) {}
+
+ template <class _CharT, class _Traits, class _Mp>
+ friend basic_istream<_CharT, _Traits>& operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t7<_Mp>& __x);
+};
+
+template <class _CharT, class _Traits, class _MoneyT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t7<_MoneyT>& __x) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typename basic_istream<_CharT, _Traits>::sentry __s(__is);
+ if (__s) {
+ typedef istreambuf_iterator<_CharT, _Traits> _Ip;
+ typedef money_get<_CharT, _Ip> _Fp;
+ ios_base::iostate __err = ios_base::goodbit;
+ const _Fp& __mf = std::use_facet<_Fp>(__is.getloc());
+ __mf.get(_Ip(__is), _Ip(), __x.__intl_, __is, __err, __x.__mon_);
+ __is.setstate(__err);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __is.__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return __is;
+}
+
+template <class _MoneyT>
+inline _LIBCPP_HIDE_FROM_ABI __iom_t7<_MoneyT> get_money(_MoneyT& __mon, bool __intl = false) {
+ return __iom_t7<_MoneyT>(__mon, __intl);
+}
+
+// put_money
+
+template <class _MoneyT>
+class __iom_t8;
+
+template <class _CharT, class _Traits, class _MoneyT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t8<_MoneyT>& __x);
+
+template <class _MoneyT>
+class __iom_t8 {
+ const _MoneyT& __mon_;
+ bool __intl_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __iom_t8(const _MoneyT& __mon, bool __intl) : __mon_(__mon), __intl_(__intl) {}
+
+ template <class _CharT, class _Traits, class _Mp>
+ friend basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t8<_Mp>& __x);
+};
+
+template <class _CharT, class _Traits, class _MoneyT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t8<_MoneyT>& __x) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typename basic_ostream<_CharT, _Traits>::sentry __s(__os);
+ if (__s) {
+ typedef ostreambuf_iterator<_CharT, _Traits> _Op;
+ typedef money_put<_CharT, _Op> _Fp;
+ const _Fp& __mf = std::use_facet<_Fp>(__os.getloc());
+ if (__mf.put(_Op(__os), __x.__intl_, __os, __os.fill(), __x.__mon_).failed())
+ __os.setstate(ios_base::badbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __os.__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return __os;
+}
+
+template <class _MoneyT>
+inline _LIBCPP_HIDE_FROM_ABI __iom_t8<_MoneyT> put_money(const _MoneyT& __mon, bool __intl = false) {
+ return __iom_t8<_MoneyT>(__mon, __intl);
+}
+
+// get_time
+
+template <class _CharT>
+class __iom_t9;
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t9<_CharT>& __x);
+
+template <class _CharT>
+class __iom_t9 {
+ tm* __tm_;
+ const _CharT* __fmt_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __iom_t9(tm* __tm, const _CharT* __fmt) : __tm_(__tm), __fmt_(__fmt) {}
+
+ template <class _Cp, class _Traits>
+ friend basic_istream<_Cp, _Traits>& operator>>(basic_istream<_Cp, _Traits>& __is, const __iom_t9<_Cp>& __x);
+};
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, const __iom_t9<_CharT>& __x) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typename basic_istream<_CharT, _Traits>::sentry __s(__is);
+ if (__s) {
+ typedef istreambuf_iterator<_CharT, _Traits> _Ip;
+ typedef time_get<_CharT, _Ip> _Fp;
+ ios_base::iostate __err = ios_base::goodbit;
+ const _Fp& __tf = std::use_facet<_Fp>(__is.getloc());
+ __tf.get(_Ip(__is), _Ip(), __is, __err, __x.__tm_, __x.__fmt_, __x.__fmt_ + _Traits::length(__x.__fmt_));
+ __is.setstate(__err);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __is.__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return __is;
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI __iom_t9<_CharT> get_time(tm* __tm, const _CharT* __fmt) {
+ return __iom_t9<_CharT>(__tm, __fmt);
+}
+
+// put_time
+
+template <class _CharT>
+class __iom_t10;
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t10<_CharT>& __x);
+
+template <class _CharT>
+class __iom_t10 {
+ const tm* __tm_;
+ const _CharT* __fmt_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __iom_t10(const tm* __tm, const _CharT* __fmt) : __tm_(__tm), __fmt_(__fmt) {}
+
+ template <class _Cp, class _Traits>
+ friend basic_ostream<_Cp, _Traits>& operator<<(basic_ostream<_Cp, _Traits>& __os, const __iom_t10<_Cp>& __x);
+};
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const __iom_t10<_CharT>& __x) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typename basic_ostream<_CharT, _Traits>::sentry __s(__os);
+ if (__s) {
+ typedef ostreambuf_iterator<_CharT, _Traits> _Op;
+ typedef time_put<_CharT, _Op> _Fp;
+ const _Fp& __tf = std::use_facet<_Fp>(__os.getloc());
+ if (__tf.put(_Op(__os), __os, __os.fill(), __x.__tm_, __x.__fmt_, __x.__fmt_ + _Traits::length(__x.__fmt_))
+ .failed())
+ __os.setstate(ios_base::badbit);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __os.__set_badbit_and_consider_rethrow();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ return __os;
+}
+
+template <class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI __iom_t10<_CharT> put_time(const tm* __tm, const _CharT* __fmt) {
+ return __iom_t10<_CharT>(__tm, __fmt);
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>& __quoted_output(
+ basic_ostream<_CharT, _Traits>& __os,
+ const _CharT* __first,
+ const _CharT* __last,
+ _CharT __delim,
+ _CharT __escape) {
+ basic_string<_CharT, _Traits> __str;
+ __str.push_back(__delim);
+ for (; __first != __last; ++__first) {
+ if (_Traits::eq(*__first, __escape) || _Traits::eq(*__first, __delim))
+ __str.push_back(__escape);
+ __str.push_back(*__first);
+ }
+ __str.push_back(__delim);
+ return std::__put_character_sequence(__os, __str.data(), __str.size());
+}
+
+template <class _CharT, class _Traits, class _String>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+__quoted_input(basic_istream<_CharT, _Traits>& __is, _String& __string, _CharT __delim, _CharT __escape) {
+ __string.clear();
+ _CharT __c;
+ __is >> __c;
+ if (__is.fail())
+ return __is;
+
+ if (!_Traits::eq(__c, __delim)) {
+ // no delimiter, read the whole string
+ __is.unget();
+ __is >> __string;
+ return __is;
+ }
+
+ __save_flags<_CharT, _Traits> __sf(__is);
+ std::noskipws(__is);
+ while (true) {
+ __is >> __c;
+ if (__is.fail())
+ break;
+ if (_Traits::eq(__c, __escape)) {
+ __is >> __c;
+ if (__is.fail())
+ break;
+ } else if (_Traits::eq(__c, __delim))
+ break;
+ __string.push_back(__c);
+ }
+ return __is;
+}
+
+template <class _CharT, class _Traits>
+struct _LIBCPP_HIDDEN __quoted_output_proxy {
+ const _CharT* __first_;
+ const _CharT* __last_;
+ _CharT __delim_;
+ _CharT __escape_;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __quoted_output_proxy(const _CharT* __f, const _CharT* __l, _CharT __d, _CharT __e)
+ : __first_(__f), __last_(__l), __delim_(__d), __escape_(__e) {}
+
+ template <class _T2, __enable_if_t<_IsSame<_Traits, void>::value || _IsSame<_Traits, _T2>::value, int> = 0>
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _T2>&
+ operator<<(basic_ostream<_CharT, _T2>& __os, const __quoted_output_proxy& __p) {
+ return std::__quoted_output(__os, __p.__first_, __p.__last_, __p.__delim_, __p.__escape_);
+ }
+};
+
+template <class _CharT, class _Traits, class _Allocator>
+struct _LIBCPP_HIDDEN __quoted_proxy {
+ basic_string<_CharT, _Traits, _Allocator>& __string_;
+ _CharT __delim_;
+ _CharT __escape_;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __quoted_proxy(basic_string<_CharT, _Traits, _Allocator>& __s, _CharT __d, _CharT __e)
+ : __string_(__s), __delim_(__d), __escape_(__e) {}
+
+ friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os, const __quoted_proxy& __p) {
+ return std::__quoted_output(
+ __os, __p.__string_.data(), __p.__string_.data() + __p.__string_.size(), __p.__delim_, __p.__escape_);
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is, const __quoted_proxy& __p) {
+ return std::__quoted_input(__is, __p.__string_, __p.__delim_, __p.__escape_);
+ }
+};
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __quoted_output_proxy<_CharT, _Traits>
+__quoted(const basic_string<_CharT, _Traits, _Allocator>& __s,
+ _CharT __delim = _CharT('"'),
+ _CharT __escape = _CharT('\\')) {
+ return __quoted_output_proxy<_CharT, _Traits>(__s.data(), __s.data() + __s.size(), __delim, __escape);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __quoted_proxy<_CharT, _Traits, _Allocator>
+__quoted(basic_string<_CharT, _Traits, _Allocator>& __s, _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\')) {
+ return __quoted_proxy<_CharT, _Traits, _Allocator>(__s, __delim, __escape);
+}
+
+#if _LIBCPP_STD_VER >= 14
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI auto quoted(const _CharT* __s, _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\')) {
+ const _CharT* __end = __s;
+ while (*__end)
+ ++__end;
+ return __quoted_output_proxy<_CharT, void>(__s, __end, __delim, __escape);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI auto
+quoted(const basic_string<_CharT, _Traits, _Allocator>& __s,
+ _CharT __delim = _CharT('"'),
+ _CharT __escape = _CharT('\\')) {
+ return __quoted_output_proxy<_CharT, _Traits>(__s.data(), __s.data() + __s.size(), __delim, __escape);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI auto
+quoted(basic_string<_CharT, _Traits, _Allocator>& __s, _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\')) {
+ return __quoted_proxy<_CharT, _Traits, _Allocator>(__s, __delim, __escape);
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI auto
+quoted(basic_string_view<_CharT, _Traits> __sv, _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\')) {
+ return __quoted_output_proxy<_CharT, _Traits>(__sv.data(), __sv.data() + __sv.size(), __delim, __escape);
+}
+
+#endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_IOMANIP
diff --git a/libcxx/include/__cxx03/ios b/libcxx/include/__cxx03/ios
new file mode 100644
index 00000000000000..d8a3643c7ad50d
--- /dev/null
+++ b/libcxx/include/__cxx03/ios
@@ -0,0 +1,889 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_IOS
+#define _LIBCPP_IOS
+
+/*
+ ios synopsis
+
+#include <iosfwd>
+
+namespace std
+{
+
+typedef OFF_T streamoff;
+typedef SZ_T streamsize;
+template <class stateT> class fpos;
+
+class ios_base
+{
+public:
+ class failure;
+
+ typedef T1 fmtflags;
+ static constexpr fmtflags boolalpha;
+ static constexpr fmtflags dec;
+ static constexpr fmtflags fixed;
+ static constexpr fmtflags hex;
+ static constexpr fmtflags internal;
+ static constexpr fmtflags left;
+ static constexpr fmtflags oct;
+ static constexpr fmtflags right;
+ static constexpr fmtflags scientific;
+ static constexpr fmtflags showbase;
+ static constexpr fmtflags showpoint;
+ static constexpr fmtflags showpos;
+ static constexpr fmtflags skipws;
+ static constexpr fmtflags unitbuf;
+ static constexpr fmtflags uppercase;
+ static constexpr fmtflags adjustfield;
+ static constexpr fmtflags basefield;
+ static constexpr fmtflags floatfield;
+
+ typedef T2 iostate;
+ static constexpr iostate badbit;
+ static constexpr iostate eofbit;
+ static constexpr iostate failbit;
+ static constexpr iostate goodbit;
+
+ typedef T3 openmode;
+ static constexpr openmode app;
+ static constexpr openmode ate;
+ static constexpr openmode binary;
+ static constexpr openmode in;
+ static constexpr openmode noreplace; // since C++23
+ static constexpr openmode out;
+ static constexpr openmode trunc;
+
+ typedef T4 seekdir;
+ static constexpr seekdir beg;
+ static constexpr seekdir cur;
+ static constexpr seekdir end;
+
+ class Init;
+
+ // 27.5.2.2 fmtflags state:
+ fmtflags flags() const;
+ fmtflags flags(fmtflags fmtfl);
+ fmtflags setf(fmtflags fmtfl);
+ fmtflags setf(fmtflags fmtfl, fmtflags mask);
+ void unsetf(fmtflags mask);
+
+ streamsize precision() const;
+ streamsize precision(streamsize prec);
+ streamsize width() const;
+ streamsize width(streamsize wide);
+
+ // 27.5.2.3 locales:
+ locale imbue(const locale& loc);
+ locale getloc() const;
+
+ // 27.5.2.5 storage:
+ static int xalloc();
+ long& iword(int index);
+ void*& pword(int index);
+
+ // destructor
+ virtual ~ios_base();
+
+ // 27.5.2.6 callbacks;
+ enum event { erase_event, imbue_event, copyfmt_event };
+ typedef void (*event_callback)(event, ios_base&, int index);
+ void register_callback(event_callback fn, int index);
+
+ ios_base(const ios_base&) = delete;
+ ios_base& operator=(const ios_base&) = delete;
+
+ static bool sync_with_stdio(bool sync = true);
+
+protected:
+ ios_base();
+};
+
+template <class charT, class traits = char_traits<charT> >
+class basic_ios
+ : public ios_base
+{
+public:
+ // types:
+ typedef charT char_type;
+ typedef typename traits::int_type int_type; // removed in C++17
+ typedef typename traits::pos_type pos_type; // removed in C++17
+ typedef typename traits::off_type off_type; // removed in C++17
+ typedef traits traits_type;
+
+ operator unspecified-bool-type() const;
+ bool operator!() const;
+ iostate rdstate() const;
+ void clear(iostate state = goodbit);
+ void setstate(iostate state);
+ bool good() const;
+ bool eof() const;
+ bool fail() const;
+ bool bad() const;
+
+ iostate exceptions() const;
+ void exceptions(iostate except);
+
+ // 27.5.4.1 Constructor/destructor:
+ explicit basic_ios(basic_streambuf<charT,traits>* sb);
+ virtual ~basic_ios();
+
+ // 27.5.4.2 Members:
+ basic_ostream<charT,traits>* tie() const;
+ basic_ostream<charT,traits>* tie(basic_ostream<charT,traits>* tiestr);
+
+ basic_streambuf<charT,traits>* rdbuf() const;
+ basic_streambuf<charT,traits>* rdbuf(basic_streambuf<charT,traits>* sb);
+
+ basic_ios& copyfmt(const basic_ios& rhs);
+
+ char_type fill() const;
+ char_type fill(char_type ch);
+
+ locale imbue(const locale& loc);
+
+ char narrow(char_type c, char dfault) const;
+ char_type widen(char c) const;
+
+ basic_ios(const basic_ios& ) = delete;
+ basic_ios& operator=(const basic_ios&) = delete;
+
+protected:
+ basic_ios();
+ void init(basic_streambuf<charT,traits>* sb);
+ void move(basic_ios& rhs);
+ void swap(basic_ios& rhs) noexcept;
+ void set_rdbuf(basic_streambuf<charT, traits>* sb);
+};
+
+// 27.5.5, manipulators:
+ios_base& boolalpha (ios_base& str);
+ios_base& noboolalpha(ios_base& str);
+ios_base& showbase (ios_base& str);
+ios_base& noshowbase (ios_base& str);
+ios_base& showpoint (ios_base& str);
+ios_base& noshowpoint(ios_base& str);
+ios_base& showpos (ios_base& str);
+ios_base& noshowpos (ios_base& str);
+ios_base& skipws (ios_base& str);
+ios_base& noskipws (ios_base& str);
+ios_base& uppercase (ios_base& str);
+ios_base& nouppercase(ios_base& str);
+ios_base& unitbuf (ios_base& str);
+ios_base& nounitbuf (ios_base& str);
+
+// 27.5.5.2 adjustfield:
+ios_base& internal (ios_base& str);
+ios_base& left (ios_base& str);
+ios_base& right (ios_base& str);
+
+// 27.5.5.3 basefield:
+ios_base& dec (ios_base& str);
+ios_base& hex (ios_base& str);
+ios_base& oct (ios_base& str);
+
+// 27.5.5.4 floatfield:
+ios_base& fixed (ios_base& str);
+ios_base& scientific (ios_base& str);
+ios_base& hexfloat (ios_base& str);
+ios_base& defaultfloat(ios_base& str);
+
+// 27.5.5.5 error reporting:
+enum class io_errc
+{
+ stream = 1
+};
+
+concept_map ErrorCodeEnum<io_errc> { };
+error_code make_error_code(io_errc e) noexcept;
+error_condition make_error_condition(io_errc e) noexcept;
+storage-class-specifier const error_category& iostream_category() noexcept;
+
+} // std
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+# include <__fwd/ios.h>
+# include <__ios/fpos.h>
+# include <__locale>
+# include <__system_error/error_category.h>
+# include <__system_error/error_code.h>
+# include <__system_error/error_condition.h>
+# include <__system_error/system_error.h>
+# include <__utility/swap.h>
+# include <__verbose_abort>
+# include <version>
+
+// standard-mandated includes
+
+// [ios.syn]
+# include <iosfwd>
+
+# if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
+# include <__atomic/atomic.h> // for __xindex_
+# endif
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+typedef ptrdiff_t streamsize;
+
+class _LIBCPP_EXPORTED_FROM_ABI ios_base {
+public:
+ class _LIBCPP_EXPORTED_FROM_ABI failure;
+
+ typedef unsigned int fmtflags;
+ static const fmtflags boolalpha = 0x0001;
+ static const fmtflags dec = 0x0002;
+ static const fmtflags fixed = 0x0004;
+ static const fmtflags hex = 0x0008;
+ static const fmtflags internal = 0x0010;
+ static const fmtflags left = 0x0020;
+ static const fmtflags oct = 0x0040;
+ static const fmtflags right = 0x0080;
+ static const fmtflags scientific = 0x0100;
+ static const fmtflags showbase = 0x0200;
+ static const fmtflags showpoint = 0x0400;
+ static const fmtflags showpos = 0x0800;
+ static const fmtflags skipws = 0x1000;
+ static const fmtflags unitbuf = 0x2000;
+ static const fmtflags uppercase = 0x4000;
+ static const fmtflags adjustfield = left | right | internal;
+ static const fmtflags basefield = dec | oct | hex;
+ static const fmtflags floatfield = scientific | fixed;
+
+ typedef unsigned int iostate;
+ static const iostate badbit = 0x1;
+ static const iostate eofbit = 0x2;
+ static const iostate failbit = 0x4;
+ static const iostate goodbit = 0x0;
+
+ typedef unsigned int openmode;
+ static const openmode app = 0x01;
+ static const openmode ate = 0x02;
+ static const openmode binary = 0x04;
+ static const openmode in = 0x08;
+ static const openmode out = 0x10;
+ static const openmode trunc = 0x20;
+# if _LIBCPP_STD_VER >= 23
+ static const openmode noreplace = 0x40;
+# endif
+
+ enum seekdir { beg, cur, end };
+
+# if _LIBCPP_STD_VER <= 14
+ typedef iostate io_state;
+ typedef openmode open_mode;
+ typedef seekdir seek_dir;
+
+ typedef std::streamoff streamoff;
+ typedef std::streampos streampos;
+# endif
+
+ class _LIBCPP_EXPORTED_FROM_ABI Init;
+
+ // 27.5.2.2 fmtflags state:
+ _LIBCPP_HIDE_FROM_ABI fmtflags flags() const;
+ _LIBCPP_HIDE_FROM_ABI fmtflags flags(fmtflags __fmtfl);
+ _LIBCPP_HIDE_FROM_ABI fmtflags setf(fmtflags __fmtfl);
+ _LIBCPP_HIDE_FROM_ABI fmtflags setf(fmtflags __fmtfl, fmtflags __mask);
+ _LIBCPP_HIDE_FROM_ABI void unsetf(fmtflags __mask);
+
+ _LIBCPP_HIDE_FROM_ABI streamsize precision() const;
+ _LIBCPP_HIDE_FROM_ABI streamsize precision(streamsize __prec);
+ _LIBCPP_HIDE_FROM_ABI streamsize width() const;
+ _LIBCPP_HIDE_FROM_ABI streamsize width(streamsize __wide);
+
+ // 27.5.2.3 locales:
+ locale imbue(const locale& __loc);
+ locale getloc() const;
+
+ // 27.5.2.5 storage:
+ static int xalloc();
+ long& iword(int __index);
+ void*& pword(int __index);
+
+ // destructor
+ virtual ~ios_base();
+
+ // 27.5.2.6 callbacks;
+ enum event { erase_event, imbue_event, copyfmt_event };
+ typedef void (*event_callback)(event, ios_base&, int __index);
+ void register_callback(event_callback __fn, int __index);
+
+ ios_base(const ios_base&) = delete;
+ ios_base& operator=(const ios_base&) = delete;
+
+ static bool sync_with_stdio(bool __sync = true);
+
+ _LIBCPP_HIDE_FROM_ABI iostate rdstate() const;
+ void clear(iostate __state = goodbit);
+ _LIBCPP_HIDE_FROM_ABI void setstate(iostate __state);
+
+ _LIBCPP_HIDE_FROM_ABI bool good() const;
+ _LIBCPP_HIDE_FROM_ABI bool eof() const;
+ _LIBCPP_HIDE_FROM_ABI bool fail() const;
+ _LIBCPP_HIDE_FROM_ABI bool bad() const;
+
+ _LIBCPP_HIDE_FROM_ABI iostate exceptions() const;
+ _LIBCPP_HIDE_FROM_ABI void exceptions(iostate __iostate);
+
+ void __set_badbit_and_consider_rethrow();
+ void __set_failbit_and_consider_rethrow();
+
+ _LIBCPP_HIDE_FROM_ABI void __setstate_nothrow(iostate __state) {
+ if (__rdbuf_)
+ __rdstate_ |= __state;
+ else
+ __rdstate_ |= __state | ios_base::badbit;
+ }
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI ios_base() : __loc_(nullptr) {
+ // Purposefully does no initialization
+ //
+ // Except for the locale, this is a sentinel to avoid destroying
+ // an uninitialized object. See
+ // test/libcxx/input.output/iostreams.base/ios.base/ios.base.cons/dtor.uninitialized.pass.cpp
+ // for the details.
+ }
+
+ void init(void* __sb);
+ _LIBCPP_HIDE_FROM_ABI void* rdbuf() const { return __rdbuf_; }
+
+ _LIBCPP_HIDE_FROM_ABI void rdbuf(void* __sb) {
+ __rdbuf_ = __sb;
+ clear();
+ }
+
+ void __call_callbacks(event);
+ void copyfmt(const ios_base&);
+ void move(ios_base&);
+ void swap(ios_base&) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI void set_rdbuf(void* __sb) { __rdbuf_ = __sb; }
+
+private:
+ // All data members must be scalars
+ fmtflags __fmtflags_;
+ streamsize __precision_;
+ streamsize __width_;
+ iostate __rdstate_;
+ iostate __exceptions_;
+ void* __rdbuf_;
+ void* __loc_;
+ event_callback* __fn_;
+ int* __index_;
+ size_t __event_size_;
+ size_t __event_cap_;
+// TODO(EricWF): Enable this for both Clang and GCC. Currently it is only
+// enabled with clang.
+# if defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS)
+ static atomic<int> __xindex_;
+# else
+ static int __xindex_;
+# endif
+ long* __iarray_;
+ size_t __iarray_size_;
+ size_t __iarray_cap_;
+ void** __parray_;
+ size_t __parray_size_;
+ size_t __parray_cap_;
+};
+
+// enum class io_errc
+_LIBCPP_DECLARE_STRONG_ENUM(io_errc){stream = 1};
+_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(io_errc)
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS is_error_code_enum<io_errc> : public true_type {};
+
+# ifdef _LIBCPP_CXX03_LANG
+template <>
+struct _LIBCPP_TEMPLATE_VIS is_error_code_enum<io_errc::__lx> : public true_type {};
+# endif
+
+_LIBCPP_EXPORTED_FROM_ABI const error_category& iostream_category() _NOEXCEPT;
+
+inline _LIBCPP_HIDE_FROM_ABI error_code make_error_code(io_errc __e) _NOEXCEPT {
+ return error_code(static_cast<int>(__e), iostream_category());
+}
+
+inline _LIBCPP_HIDE_FROM_ABI error_condition make_error_condition(io_errc __e) _NOEXCEPT {
+ return error_condition(static_cast<int>(__e), iostream_category());
+}
+
+class _LIBCPP_EXPORTED_FROM_ABI ios_base::failure : public system_error {
+public:
+ explicit failure(const string& __msg, const error_code& __ec = io_errc::stream);
+ explicit failure(const char* __msg, const error_code& __ec = io_errc::stream);
+ _LIBCPP_HIDE_FROM_ABI failure(const failure&) _NOEXCEPT = default;
+ ~failure() _NOEXCEPT override;
+};
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_failure(char const* __msg) {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw ios_base::failure(__msg);
+# else
+ _LIBCPP_VERBOSE_ABORT("ios_base::failure was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+# endif
+}
+
+class _LIBCPP_EXPORTED_FROM_ABI ios_base::Init {
+public:
+ Init();
+ ~Init();
+};
+
+// fmtflags
+
+inline _LIBCPP_HIDE_FROM_ABI ios_base::fmtflags ios_base::flags() const { return __fmtflags_; }
+
+inline _LIBCPP_HIDE_FROM_ABI ios_base::fmtflags ios_base::flags(fmtflags __fmtfl) {
+ fmtflags __r = __fmtflags_;
+ __fmtflags_ = __fmtfl;
+ return __r;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI ios_base::fmtflags ios_base::setf(fmtflags __fmtfl) {
+ fmtflags __r = __fmtflags_;
+ __fmtflags_ |= __fmtfl;
+ return __r;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void ios_base::unsetf(fmtflags __mask) { __fmtflags_ &= ~__mask; }
+
+inline _LIBCPP_HIDE_FROM_ABI ios_base::fmtflags ios_base::setf(fmtflags __fmtfl, fmtflags __mask) {
+ fmtflags __r = __fmtflags_;
+ unsetf(__mask);
+ __fmtflags_ |= __fmtfl & __mask;
+ return __r;
+}
+
+// precision
+
+inline _LIBCPP_HIDE_FROM_ABI streamsize ios_base::precision() const { return __precision_; }
+
+inline _LIBCPP_HIDE_FROM_ABI streamsize ios_base::precision(streamsize __prec) {
+ streamsize __r = __precision_;
+ __precision_ = __prec;
+ return __r;
+}
+
+// width
+
+inline _LIBCPP_HIDE_FROM_ABI streamsize ios_base::width() const { return __width_; }
+
+inline _LIBCPP_HIDE_FROM_ABI streamsize ios_base::width(streamsize __wide) {
+ streamsize __r = __width_;
+ __width_ = __wide;
+ return __r;
+}
+
+// iostate
+
+inline _LIBCPP_HIDE_FROM_ABI ios_base::iostate ios_base::rdstate() const { return __rdstate_; }
+
+inline _LIBCPP_HIDE_FROM_ABI void ios_base::setstate(iostate __state) { clear(__rdstate_ | __state); }
+
+inline _LIBCPP_HIDE_FROM_ABI bool ios_base::good() const { return __rdstate_ == 0; }
+
+inline _LIBCPP_HIDE_FROM_ABI bool ios_base::eof() const { return (__rdstate_ & eofbit) != 0; }
+
+inline _LIBCPP_HIDE_FROM_ABI bool ios_base::fail() const { return (__rdstate_ & (failbit | badbit)) != 0; }
+
+inline _LIBCPP_HIDE_FROM_ABI bool ios_base::bad() const { return (__rdstate_ & badbit) != 0; }
+
+inline _LIBCPP_HIDE_FROM_ABI ios_base::iostate ios_base::exceptions() const { return __exceptions_; }
+
+inline _LIBCPP_HIDE_FROM_ABI void ios_base::exceptions(iostate __iostate) {
+ __exceptions_ = __iostate;
+ clear(__rdstate_);
+}
+
+template <class _Traits>
+// Attribute 'packed' is used to keep the layout compatible with the previous
+// definition of the '__fill_' and '_set_' pair in basic_ios on AIX & z/OS.
+struct _LIBCPP_PACKED _FillHelper {
+ _LIBCPP_HIDE_FROM_ABI void __init() { __set_ = false; }
+ _LIBCPP_HIDE_FROM_ABI _FillHelper& operator=(typename _Traits::int_type __x) {
+ __set_ = true;
+ __fill_val_ = __x;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI bool __is_set() const { return __set_; }
+ _LIBCPP_HIDE_FROM_ABI typename _Traits::int_type __get() const { return __fill_val_; }
+
+private:
+ typename _Traits::int_type __fill_val_;
+ bool __set_;
+};
+
+template <class _Traits>
+struct _LIBCPP_PACKED _SentinelValueFill {
+ _LIBCPP_HIDE_FROM_ABI void __init() { __fill_val_ = _Traits::eof(); }
+ _LIBCPP_HIDE_FROM_ABI _SentinelValueFill& operator=(typename _Traits::int_type __x) {
+ __fill_val_ = __x;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI bool __is_set() const { return __fill_val_ != _Traits::eof(); }
+ _LIBCPP_HIDE_FROM_ABI typename _Traits::int_type __get() const { return __fill_val_; }
+
+private:
+ typename _Traits::int_type __fill_val_;
+};
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_ios : public ios_base {
+public:
+ // types:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ static_assert(is_same<_CharT, typename traits_type::char_type>::value,
+ "traits_type::char_type must be the same type as CharT");
+
+# ifdef _LIBCPP_CXX03_LANG
+ // Preserve the ability to compare with literal 0,
+ // and implicitly convert to bool, but not implicitly convert to int.
+ _LIBCPP_HIDE_FROM_ABI operator void*() const { return fail() ? nullptr : (void*)this; }
+# else
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const { return !fail(); }
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI bool operator!() const { return fail(); }
+ _LIBCPP_HIDE_FROM_ABI iostate rdstate() const { return ios_base::rdstate(); }
+ _LIBCPP_HIDE_FROM_ABI void clear(iostate __state = goodbit) { ios_base::clear(__state); }
+ _LIBCPP_HIDE_FROM_ABI void setstate(iostate __state) { ios_base::setstate(__state); }
+ _LIBCPP_HIDE_FROM_ABI bool good() const { return ios_base::good(); }
+ _LIBCPP_HIDE_FROM_ABI bool eof() const { return ios_base::eof(); }
+ _LIBCPP_HIDE_FROM_ABI bool fail() const { return ios_base::fail(); }
+ _LIBCPP_HIDE_FROM_ABI bool bad() const { return ios_base::bad(); }
+
+ _LIBCPP_HIDE_FROM_ABI iostate exceptions() const { return ios_base::exceptions(); }
+ _LIBCPP_HIDE_FROM_ABI void exceptions(iostate __iostate) { ios_base::exceptions(__iostate); }
+
+ // 27.5.4.1 Constructor/destructor:
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ios(basic_streambuf<char_type, traits_type>* __sb);
+ ~basic_ios() override;
+
+ // 27.5.4.2 Members:
+ _LIBCPP_HIDE_FROM_ABI basic_ostream<char_type, traits_type>* tie() const;
+ _LIBCPP_HIDE_FROM_ABI basic_ostream<char_type, traits_type>* tie(basic_ostream<char_type, traits_type>* __tiestr);
+
+ _LIBCPP_HIDE_FROM_ABI basic_streambuf<char_type, traits_type>* rdbuf() const;
+ _LIBCPP_HIDE_FROM_ABI basic_streambuf<char_type, traits_type>* rdbuf(basic_streambuf<char_type, traits_type>* __sb);
+
+ basic_ios& copyfmt(const basic_ios& __rhs);
+
+ _LIBCPP_HIDE_FROM_ABI char_type fill() const;
+ _LIBCPP_HIDE_FROM_ABI char_type fill(char_type __ch);
+
+ _LIBCPP_HIDE_FROM_ABI locale imbue(const locale& __loc);
+
+ _LIBCPP_HIDE_FROM_ABI char narrow(char_type __c, char __dfault) const;
+ _LIBCPP_HIDE_FROM_ABI char_type widen(char __c) const;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI basic_ios() {
+ // purposefully does no initialization
+ // since the destructor does nothing this does not have ios_base issues.
+ }
+ _LIBCPP_HIDE_FROM_ABI void init(basic_streambuf<char_type, traits_type>* __sb);
+
+ _LIBCPP_HIDE_FROM_ABI void move(basic_ios& __rhs);
+ _LIBCPP_HIDE_FROM_ABI void move(basic_ios&& __rhs) { move(__rhs); }
+ _LIBCPP_HIDE_FROM_ABI void swap(basic_ios& __rhs) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI void set_rdbuf(basic_streambuf<char_type, traits_type>* __sb);
+
+private:
+ basic_ostream<char_type, traits_type>* __tie_;
+
+#if defined(_LIBCPP_ABI_IOS_ALLOW_ARBITRARY_FILL_VALUE)
+ using _FillType = _FillHelper<traits_type>;
+#else
+ using _FillType = _SentinelValueFill<traits_type>;
+#endif
+ mutable _FillType __fill_;
+};
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_ios<_CharT, _Traits>::basic_ios(basic_streambuf<char_type, traits_type>* __sb) {
+ init(__sb);
+}
+
+template <class _CharT, class _Traits>
+basic_ios<_CharT, _Traits>::~basic_ios() {}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void basic_ios<_CharT, _Traits>::init(basic_streambuf<char_type, traits_type>* __sb) {
+ ios_base::init(__sb);
+ __tie_ = nullptr;
+ __fill_.__init();
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>* basic_ios<_CharT, _Traits>::tie() const {
+ return __tie_;
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>*
+basic_ios<_CharT, _Traits>::tie(basic_ostream<char_type, traits_type>* __tiestr) {
+ basic_ostream<char_type, traits_type>* __r = __tie_;
+ __tie_ = __tiestr;
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_streambuf<_CharT, _Traits>* basic_ios<_CharT, _Traits>::rdbuf() const {
+ return static_cast<basic_streambuf<char_type, traits_type>*>(ios_base::rdbuf());
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_streambuf<_CharT, _Traits>*
+basic_ios<_CharT, _Traits>::rdbuf(basic_streambuf<char_type, traits_type>* __sb) {
+ basic_streambuf<char_type, traits_type>* __r = rdbuf();
+ ios_base::rdbuf(__sb);
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI locale basic_ios<_CharT, _Traits>::imbue(const locale& __loc) {
+ locale __r = getloc();
+ ios_base::imbue(__loc);
+ if (rdbuf())
+ rdbuf()->pubimbue(__loc);
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI char basic_ios<_CharT, _Traits>::narrow(char_type __c, char __dfault) const {
+ return std::use_facet<ctype<char_type> >(getloc()).narrow(__c, __dfault);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI _CharT basic_ios<_CharT, _Traits>::widen(char __c) const {
+ return std::use_facet<ctype<char_type> >(getloc()).widen(__c);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI _CharT basic_ios<_CharT, _Traits>::fill() const {
+ if (!__fill_.__is_set())
+ __fill_ = widen(' ');
+ return __fill_.__get();
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI _CharT basic_ios<_CharT, _Traits>::fill(char_type __ch) {
+ if (!__fill_.__is_set())
+ __fill_ = widen(' ');
+ char_type __r = __fill_.__get();
+ __fill_ = __ch;
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+basic_ios<_CharT, _Traits>& basic_ios<_CharT, _Traits>::copyfmt(const basic_ios& __rhs) {
+ if (this != &__rhs) {
+ __call_callbacks(erase_event);
+ ios_base::copyfmt(__rhs);
+ __tie_ = __rhs.__tie_;
+ __fill_ = __rhs.__fill_;
+ __call_callbacks(copyfmt_event);
+ exceptions(__rhs.exceptions());
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void basic_ios<_CharT, _Traits>::move(basic_ios& __rhs) {
+ ios_base::move(__rhs);
+ __tie_ = __rhs.__tie_;
+ __rhs.__tie_ = nullptr;
+ __fill_ = __rhs.__fill_;
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void basic_ios<_CharT, _Traits>::swap(basic_ios& __rhs) _NOEXCEPT {
+ ios_base::swap(__rhs);
+ std::swap(__tie_, __rhs.__tie_);
+ std::swap(__fill_, __rhs.__fill_);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void basic_ios<_CharT, _Traits>::set_rdbuf(basic_streambuf<char_type, traits_type>* __sb) {
+ ios_base::set_rdbuf(__sb);
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ios<char>;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ios<wchar_t>;
+# endif
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& boolalpha(ios_base& __str) {
+ __str.setf(ios_base::boolalpha);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& noboolalpha(ios_base& __str) {
+ __str.unsetf(ios_base::boolalpha);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& showbase(ios_base& __str) {
+ __str.setf(ios_base::showbase);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& noshowbase(ios_base& __str) {
+ __str.unsetf(ios_base::showbase);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& showpoint(ios_base& __str) {
+ __str.setf(ios_base::showpoint);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& noshowpoint(ios_base& __str) {
+ __str.unsetf(ios_base::showpoint);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& showpos(ios_base& __str) {
+ __str.setf(ios_base::showpos);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& noshowpos(ios_base& __str) {
+ __str.unsetf(ios_base::showpos);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& skipws(ios_base& __str) {
+ __str.setf(ios_base::skipws);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& noskipws(ios_base& __str) {
+ __str.unsetf(ios_base::skipws);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& uppercase(ios_base& __str) {
+ __str.setf(ios_base::uppercase);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& nouppercase(ios_base& __str) {
+ __str.unsetf(ios_base::uppercase);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& unitbuf(ios_base& __str) {
+ __str.setf(ios_base::unitbuf);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& nounitbuf(ios_base& __str) {
+ __str.unsetf(ios_base::unitbuf);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& internal(ios_base& __str) {
+ __str.setf(ios_base::internal, ios_base::adjustfield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& left(ios_base& __str) {
+ __str.setf(ios_base::left, ios_base::adjustfield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& right(ios_base& __str) {
+ __str.setf(ios_base::right, ios_base::adjustfield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& dec(ios_base& __str) {
+ __str.setf(ios_base::dec, ios_base::basefield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& hex(ios_base& __str) {
+ __str.setf(ios_base::hex, ios_base::basefield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& oct(ios_base& __str) {
+ __str.setf(ios_base::oct, ios_base::basefield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& fixed(ios_base& __str) {
+ __str.setf(ios_base::fixed, ios_base::floatfield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& scientific(ios_base& __str) {
+ __str.setf(ios_base::scientific, ios_base::floatfield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& hexfloat(ios_base& __str) {
+ __str.setf(ios_base::fixed | ios_base::scientific, ios_base::floatfield);
+ return __str;
+}
+
+_LIBCPP_HIDE_FROM_ABI inline ios_base& defaultfloat(ios_base& __str) {
+ __str.unsetf(ios_base::floatfield);
+ return __str;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstddef>
+# include <cstdlib>
+# include <cstring>
+# include <initializer_list>
+# include <limits>
+# include <mutex>
+# include <new>
+# include <stdexcept>
+# include <system_error>
+# include <type_traits>
+# include <typeinfo>
+#endif
+
+#endif // _LIBCPP_IOS
diff --git a/libcxx/include/__cxx03/iosfwd b/libcxx/include/__cxx03/iosfwd
new file mode 100644
index 00000000000000..051c73995e98b4
--- /dev/null
+++ b/libcxx/include/__cxx03/iosfwd
@@ -0,0 +1,186 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_IOSFWD
+#define _LIBCPP_IOSFWD
+
+/*
+ iosfwd synopsis
+
+namespace std
+{
+
+template<class charT> struct char_traits;
+template<> struct char_traits<char>;
+template<> struct char_traits<char8_t>; // C++20
+template<> struct char_traits<char16_t>;
+template<> struct char_traits<char32_t>;
+template<> struct char_traits<wchar_t>;
+
+template<class T> class allocator;
+
+template <class charT, class traits = char_traits<charT> > class basic_ios;
+
+template <class charT, class traits = char_traits<charT> > class basic_streambuf;
+template <class charT, class traits = char_traits<charT> > class basic_istream;
+template <class charT, class traits = char_traits<charT> > class basic_ostream;
+template <class charT, class traits = char_traits<charT> > class basic_iostream;
+
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+ class basic_stringbuf;
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+ class basic_istringstream;
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+ class basic_ostringstream;
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+ class basic_stringstream;
+
+template <class charT, class traits = char_traits<charT> > class basic_filebuf;
+template <class charT, class traits = char_traits<charT> > class basic_ifstream;
+template <class charT, class traits = char_traits<charT> > class basic_ofstream;
+template <class charT, class traits = char_traits<charT> > class basic_fstream;
+
+template <class charT, class traits = char_traits<charT> > class istreambuf_iterator;
+template <class charT, class traits = char_traits<charT> > class ostreambuf_iterator;
+
+typedef basic_ios<char> ios;
+typedef basic_ios<wchar_t> wios;
+
+typedef basic_streambuf<char> streambuf;
+typedef basic_istream<char> istream;
+typedef basic_ostream<char> ostream;
+typedef basic_iostream<char> iostream;
+
+typedef basic_stringbuf<char> stringbuf;
+typedef basic_istringstream<char> istringstream;
+typedef basic_ostringstream<char> ostringstream;
+typedef basic_stringstream<char> stringstream;
+
+typedef basic_filebuf<char> filebuf;
+typedef basic_ifstream<char> ifstream;
+typedef basic_ofstream<char> ofstream;
+typedef basic_fstream<char> fstream;
+
+typedef basic_streambuf<wchar_t> wstreambuf;
+typedef basic_istream<wchar_t> wistream;
+typedef basic_ostream<wchar_t> wostream;
+typedef basic_iostream<wchar_t> wiostream;
+
+typedef basic_stringbuf<wchar_t> wstringbuf;
+typedef basic_istringstream<wchar_t> wistringstream;
+typedef basic_ostringstream<wchar_t> wostringstream;
+typedef basic_stringstream<wchar_t> wstringstream;
+
+typedef basic_filebuf<wchar_t> wfilebuf;
+typedef basic_ifstream<wchar_t> wifstream;
+typedef basic_ofstream<wchar_t> wofstream;
+typedef basic_fstream<wchar_t> wfstream;
+
+template <class state> class fpos;
+using streampos = fpos<char_traits<char>::state_type>;
+using wstreampos = fpos<char_traits<wchar_t>::state_type>;
+using u8streampos = fpos<char_traits<char8_t>::state_type>; // C++20
+using u16streampos = fpos<char_traits<char16_t>::state_type>;
+using u32streampos = fpos<char_traits<char32_t>::state_type>;
+
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT>>
+ class basic_syncbuf; // C++20
+
+using syncbuf = basic_syncbuf<char>; // C++20
+using wsyncbuf = basic_syncbuf<wchar_t>; // C++20
+
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT>>
+ class basic_osyncstream; // C++20
+
+using osyncstream = basic_osyncstream<char>; // C++20
+using wosyncstream = basic_osyncstream<wchar_t>; // C++20
+
+} // std
+
+*/
+
+#include <__config>
+#include <__fwd/fstream.h>
+#include <__fwd/ios.h>
+#include <__fwd/istream.h>
+#include <__fwd/memory.h>
+#include <__fwd/ostream.h>
+#include <__fwd/sstream.h>
+#include <__fwd/streambuf.h>
+#include <__fwd/string.h>
+#include <__std_mbstate_t.h>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS istreambuf_iterator;
+template <class _CharT, class _Traits = char_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS ostreambuf_iterator;
+
+template <class _State>
+class _LIBCPP_TEMPLATE_VIS fpos;
+typedef fpos<mbstate_t> streampos;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+typedef fpos<mbstate_t> wstreampos;
+#endif
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+typedef fpos<mbstate_t> u8streampos;
+#endif
+typedef fpos<mbstate_t> u16streampos;
+typedef fpos<mbstate_t> u32streampos;
+
+#if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_SYNCSTREAM)
+
+template <class _CharT, class _Traits = char_traits<_CharT>, class _Allocator = allocator<_CharT>>
+class basic_syncbuf;
+
+using syncbuf = basic_syncbuf<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wsyncbuf = basic_syncbuf<wchar_t>;
+# endif
+
+template <class _CharT, class _Traits = char_traits<_CharT>, class _Allocator = allocator<_CharT>>
+class basic_osyncstream;
+
+using osyncstream = basic_osyncstream<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wosyncstream = basic_osyncstream<wchar_t>;
+# endif
+
+#endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_SYNCSTREAM)
+
+template <class _CharT, class _Traits>
+class __save_flags {
+ typedef basic_ios<_CharT, _Traits> __stream_type;
+ typedef typename __stream_type::fmtflags fmtflags;
+
+ __stream_type& __stream_;
+ fmtflags __fmtflags_;
+ _CharT __fill_;
+
+public:
+ __save_flags(const __save_flags&) = delete;
+ __save_flags& operator=(const __save_flags&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __save_flags(__stream_type& __stream)
+ : __stream_(__stream), __fmtflags_(__stream.flags()), __fill_(__stream.fill()) {}
+ _LIBCPP_HIDE_FROM_ABI ~__save_flags() {
+ __stream_.flags(__fmtflags_);
+ __stream_.fill(__fill_);
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_IOSFWD
diff --git a/libcxx/include/__cxx03/iostream b/libcxx/include/__cxx03/iostream
new file mode 100644
index 00000000000000..5df45c6d3f78e7
--- /dev/null
+++ b/libcxx/include/__cxx03/iostream
@@ -0,0 +1,67 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_IOSTREAM
+#define _LIBCPP_IOSTREAM
+
+/*
+ iostream synopsis
+
+#include <ios>
+#include <istream>
+#include <ostream>
+#include <streambuf>
+
+namespace std {
+
+extern istream cin;
+extern ostream cout;
+extern ostream cerr;
+extern ostream clog;
+extern wistream wcin;
+extern wostream wcout;
+extern wostream wcerr;
+extern wostream wclog;
+
+} // std
+
+*/
+
+#include <__config>
+#include <version>
+
+// standard-mandated includes
+
+// [iostream.syn]
+#include <ios>
+#include <istream>
+#include <ostream>
+#include <streambuf>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+extern _LIBCPP_EXPORTED_FROM_ABI istream cin;
+extern _LIBCPP_EXPORTED_FROM_ABI ostream cout;
+extern _LIBCPP_EXPORTED_FROM_ABI ostream cerr;
+extern _LIBCPP_EXPORTED_FROM_ABI ostream clog;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern _LIBCPP_EXPORTED_FROM_ABI wistream wcin;
+extern _LIBCPP_EXPORTED_FROM_ABI wostream wcout;
+extern _LIBCPP_EXPORTED_FROM_ABI wostream wcerr;
+extern _LIBCPP_EXPORTED_FROM_ABI wostream wclog;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_IOSTREAM
diff --git a/libcxx/include/__cxx03/istream b/libcxx/include/__cxx03/istream
new file mode 100644
index 00000000000000..d2b577a9ad9efc
--- /dev/null
+++ b/libcxx/include/__cxx03/istream
@@ -0,0 +1,1373 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_ISTREAM
+#define _LIBCPP_ISTREAM
+
+/*
+ istream synopsis
+
+template <class charT, class traits = char_traits<charT> >
+class basic_istream
+ : virtual public basic_ios<charT,traits>
+{
+public:
+ // types (inherited from basic_ios (27.5.4)):
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ // 27.7.1.1.1 Constructor/destructor:
+ explicit basic_istream(basic_streambuf<char_type, traits_type>* sb);
+ basic_istream(basic_istream&& rhs);
+ virtual ~basic_istream();
+
+ // 27.7.1.1.2 Assign/swap:
+ basic_istream& operator=(basic_istream&& rhs);
+ void swap(basic_istream& rhs);
+
+ // 27.7.1.1.3 Prefix/suffix:
+ class sentry;
+
+ // 27.7.1.2 Formatted input:
+ basic_istream& operator>>(basic_istream& (*pf)(basic_istream&));
+ basic_istream& operator>>(basic_ios<char_type, traits_type>&
+ (*pf)(basic_ios<char_type, traits_type>&));
+ basic_istream& operator>>(ios_base& (*pf)(ios_base&));
+ basic_istream& operator>>(basic_streambuf<char_type, traits_type>* sb);
+ basic_istream& operator>>(bool& n);
+ basic_istream& operator>>(short& n);
+ basic_istream& operator>>(unsigned short& n);
+ basic_istream& operator>>(int& n);
+ basic_istream& operator>>(unsigned int& n);
+ basic_istream& operator>>(long& n);
+ basic_istream& operator>>(unsigned long& n);
+ basic_istream& operator>>(long long& n);
+ basic_istream& operator>>(unsigned long long& n);
+ basic_istream& operator>>(float& f);
+ basic_istream& operator>>(double& f);
+ basic_istream& operator>>(long double& f);
+ basic_istream& operator>>(void*& p);
+
+ // 27.7.1.3 Unformatted input:
+ streamsize gcount() const;
+ int_type get();
+ basic_istream& get(char_type& c);
+ basic_istream& get(char_type* s, streamsize n);
+ basic_istream& get(char_type* s, streamsize n, char_type delim);
+ basic_istream& get(basic_streambuf<char_type,traits_type>& sb);
+ basic_istream& get(basic_streambuf<char_type,traits_type>& sb, char_type delim);
+
+ basic_istream& getline(char_type* s, streamsize n);
+ basic_istream& getline(char_type* s, streamsize n, char_type delim);
+
+ basic_istream& ignore(streamsize n = 1, int_type delim = traits_type::eof());
+ int_type peek();
+ basic_istream& read (char_type* s, streamsize n);
+ streamsize readsome(char_type* s, streamsize n);
+
+ basic_istream& putback(char_type c);
+ basic_istream& unget();
+ int sync();
+
+ pos_type tellg();
+ basic_istream& seekg(pos_type);
+ basic_istream& seekg(off_type, ios_base::seekdir);
+protected:
+ basic_istream(const basic_istream& rhs) = delete;
+ basic_istream(basic_istream&& rhs);
+ // 27.7.2.1.2 Assign/swap:
+ basic_istream& operator=(const basic_istream& rhs) = delete;
+ basic_istream& operator=(basic_istream&& rhs);
+ void swap(basic_istream& rhs);
+};
+
+// 27.7.1.2.3 character extraction templates:
+template<class charT, class traits>
+ basic_istream<charT,traits>& operator>>(basic_istream<charT,traits>&, charT&);
+
+template<class traits>
+ basic_istream<char,traits>& operator>>(basic_istream<char,traits>&, unsigned char&);
+
+template<class traits>
+ basic_istream<char,traits>& operator>>(basic_istream<char,traits>&, signed char&);
+
+template<class charT, class traits>
+ basic_istream<charT,traits>& operator>>(basic_istream<charT,traits>&, charT*);
+
+template<class traits>
+ basic_istream<char,traits>& operator>>(basic_istream<char,traits>&, unsigned char*);
+
+template<class traits>
+ basic_istream<char,traits>& operator>>(basic_istream<char,traits>&, signed char*);
+
+template <class charT, class traits>
+ void
+ swap(basic_istream<charT, traits>& x, basic_istream<charT, traits>& y);
+
+typedef basic_istream<char> istream;
+typedef basic_istream<wchar_t> wistream;
+
+template <class charT, class traits = char_traits<charT> >
+class basic_iostream :
+ public basic_istream<charT,traits>,
+ public basic_ostream<charT,traits>
+{
+public:
+ // types:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ // constructor/destructor
+ explicit basic_iostream(basic_streambuf<char_type, traits_type>* sb);
+ basic_iostream(basic_iostream&& rhs);
+ virtual ~basic_iostream();
+
+ // assign/swap
+ basic_iostream& operator=(basic_iostream&& rhs);
+ void swap(basic_iostream& rhs);
+};
+
+template <class charT, class traits>
+ void
+ swap(basic_iostream<charT, traits>& x, basic_iostream<charT, traits>& y);
+
+typedef basic_iostream<char> iostream;
+typedef basic_iostream<wchar_t> wiostream;
+
+template <class charT, class traits>
+ basic_istream<charT,traits>&
+ ws(basic_istream<charT,traits>& is);
+
+// rvalue stream extraction
+template <class Stream, class T>
+ Stream&& operator>>(Stream&& is, T&& x);
+
+} // std
+
+*/
+
+#include <__config>
+#include <__fwd/istream.h>
+#include <__iterator/istreambuf_iterator.h>
+#include <__ostream/basic_ostream.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_base_of.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <bitset>
+#include <ios>
+#include <locale>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_istream : virtual public basic_ios<_CharT, _Traits> {
+ streamsize __gc_;
+
+ _LIBCPP_HIDE_FROM_ABI void __inc_gcount() {
+ if (__gc_ < numeric_limits<streamsize>::max())
+ ++__gc_;
+ }
+
+public:
+ // types (inherited from basic_ios (27.5.4)):
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ // 27.7.1.1.1 Constructor/destructor:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 explicit basic_istream(basic_streambuf<char_type, traits_type>* __sb)
+ : __gc_(0) {
+ this->init(__sb);
+ }
+ ~basic_istream() override;
+
+protected:
+ inline _LIBCPP_HIDE_FROM_ABI basic_istream(basic_istream&& __rhs);
+
+ // 27.7.1.1.2 Assign/swap:
+ inline _LIBCPP_HIDE_FROM_ABI basic_istream& operator=(basic_istream&& __rhs);
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void swap(basic_istream& __rhs) {
+ std::swap(__gc_, __rhs.__gc_);
+ basic_ios<char_type, traits_type>::swap(__rhs);
+ }
+
+public:
+ basic_istream(const basic_istream& __rhs) = delete;
+ basic_istream& operator=(const basic_istream& __rhs) = delete;
+
+ // 27.7.1.1.3 Prefix/suffix:
+ class _LIBCPP_TEMPLATE_VIS sentry;
+
+ // 27.7.1.2 Formatted input:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_istream& operator>>(basic_istream& (*__pf)(basic_istream&)) {
+ return __pf(*this);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_istream&
+ operator>>(basic_ios<char_type, traits_type>& (*__pf)(basic_ios<char_type, traits_type>&)) {
+ __pf(*this);
+ return *this;
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_istream& operator>>(ios_base& (*__pf)(ios_base&)) {
+ __pf(*this);
+ return *this;
+ }
+
+ basic_istream& operator>>(basic_streambuf<char_type, traits_type>* __sb);
+ basic_istream& operator>>(bool& __n);
+ basic_istream& operator>>(short& __n);
+ basic_istream& operator>>(unsigned short& __n);
+ basic_istream& operator>>(int& __n);
+ basic_istream& operator>>(unsigned int& __n);
+ basic_istream& operator>>(long& __n);
+ basic_istream& operator>>(unsigned long& __n);
+ basic_istream& operator>>(long long& __n);
+ basic_istream& operator>>(unsigned long long& __n);
+ basic_istream& operator>>(float& __f);
+ basic_istream& operator>>(double& __f);
+ basic_istream& operator>>(long double& __f);
+ basic_istream& operator>>(void*& __p);
+
+ // 27.7.1.3 Unformatted input:
+ _LIBCPP_HIDE_FROM_ABI streamsize gcount() const { return __gc_; }
+ int_type get();
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_istream& get(char_type& __c) {
+ int_type __ch = get();
+ if (__ch != traits_type::eof())
+ __c = traits_type::to_char_type(__ch);
+ return *this;
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_istream& get(char_type* __s, streamsize __n) {
+ return get(__s, __n, this->widen('\n'));
+ }
+
+ basic_istream& get(char_type* __s, streamsize __n, char_type __dlm);
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_istream& get(basic_streambuf<char_type, traits_type>& __sb) {
+ return get(__sb, this->widen('\n'));
+ }
+
+ basic_istream& get(basic_streambuf<char_type, traits_type>& __sb, char_type __dlm);
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_istream& getline(char_type* __s, streamsize __n) {
+ return getline(__s, __n, this->widen('\n'));
+ }
+
+ basic_istream& getline(char_type* __s, streamsize __n, char_type __dlm);
+
+ basic_istream& ignore(streamsize __n = 1, int_type __dlm = traits_type::eof());
+ int_type peek();
+ basic_istream& read(char_type* __s, streamsize __n);
+ streamsize readsome(char_type* __s, streamsize __n);
+
+ basic_istream& putback(char_type __c);
+ basic_istream& unget();
+ int sync();
+
+ pos_type tellg();
+ basic_istream& seekg(pos_type __pos);
+ basic_istream& seekg(off_type __off, ios_base::seekdir __dir);
+};
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_istream<_CharT, _Traits>::sentry {
+ bool __ok_;
+
+public:
+ explicit sentry(basic_istream<_CharT, _Traits>& __is, bool __noskipws = false);
+ // ~sentry() = default;
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const { return __ok_; }
+
+ sentry(const sentry&) = delete;
+ sentry& operator=(const sentry&) = delete;
+};
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>::sentry::sentry(basic_istream<_CharT, _Traits>& __is, bool __noskipws) : __ok_(false) {
+ if (__is.good()) {
+ if (__is.tie())
+ __is.tie()->flush();
+ if (!__noskipws && (__is.flags() & ios_base::skipws)) {
+ typedef istreambuf_iterator<_CharT, _Traits> _Ip;
+ const ctype<_CharT>& __ct = std::use_facet<ctype<_CharT> >(__is.getloc());
+ _Ip __i(__is);
+ _Ip __eof;
+ for (; __i != __eof; ++__i)
+ if (!__ct.is(__ct.space, *__i))
+ break;
+ if (__i == __eof)
+ __is.setstate(ios_base::failbit | ios_base::eofbit);
+ }
+ __ok_ = __is.good();
+ } else
+ __is.setstate(ios_base::failbit);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>::basic_istream(basic_istream&& __rhs) : __gc_(__rhs.__gc_) {
+ __rhs.__gc_ = 0;
+ this->move(__rhs);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator=(basic_istream&& __rhs) {
+ swap(__rhs);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>::~basic_istream() {}
+
+template <class _Tp, class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+__input_arithmetic(basic_istream<_CharT, _Traits>& __is, _Tp& __n) {
+ ios_base::iostate __state = ios_base::goodbit;
+ typename basic_istream<_CharT, _Traits>::sentry __s(__is);
+ if (__s) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef istreambuf_iterator<_CharT, _Traits> _Ip;
+ typedef num_get<_CharT, _Ip> _Fp;
+ std::use_facet<_Fp>(__is.getloc()).get(_Ip(__is), _Ip(), __is, __state, __n);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ __is.__setstate_nothrow(__state);
+ if (__is.exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif
+ __is.setstate(__state);
+ }
+ return __is;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(unsigned short& __n) {
+ return std::__input_arithmetic<unsigned short>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(unsigned int& __n) {
+ return std::__input_arithmetic<unsigned int>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(long& __n) {
+ return std::__input_arithmetic<long>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(unsigned long& __n) {
+ return std::__input_arithmetic<unsigned long>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(long long& __n) {
+ return std::__input_arithmetic<long long>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(unsigned long long& __n) {
+ return std::__input_arithmetic<unsigned long long>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(float& __n) {
+ return std::__input_arithmetic<float>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(double& __n) {
+ return std::__input_arithmetic<double>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(long double& __n) {
+ return std::__input_arithmetic<long double>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(bool& __n) {
+ return std::__input_arithmetic<bool>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(void*& __n) {
+ return std::__input_arithmetic<void*>(*this, __n);
+}
+
+template <class _Tp, class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+__input_arithmetic_with_numeric_limits(basic_istream<_CharT, _Traits>& __is, _Tp& __n) {
+ ios_base::iostate __state = ios_base::goodbit;
+ typename basic_istream<_CharT, _Traits>::sentry __s(__is);
+ if (__s) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef istreambuf_iterator<_CharT, _Traits> _Ip;
+ typedef num_get<_CharT, _Ip> _Fp;
+ long __temp;
+ std::use_facet<_Fp>(__is.getloc()).get(_Ip(__is), _Ip(), __is, __state, __temp);
+ if (__temp < numeric_limits<_Tp>::min()) {
+ __state |= ios_base::failbit;
+ __n = numeric_limits<_Tp>::min();
+ } else if (__temp > numeric_limits<_Tp>::max()) {
+ __state |= ios_base::failbit;
+ __n = numeric_limits<_Tp>::max();
+ } else {
+ __n = static_cast<_Tp>(__temp);
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ __is.__setstate_nothrow(__state);
+ if (__is.exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __is.setstate(__state);
+ }
+ return __is;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(short& __n) {
+ return std::__input_arithmetic_with_numeric_limits<short>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::operator>>(int& __n) {
+ return std::__input_arithmetic_with_numeric_limits<int>(*this, __n);
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+__input_c_string(basic_istream<_CharT, _Traits>& __is, _CharT* __p, size_t __n) {
+ ios_base::iostate __state = ios_base::goodbit;
+ typename basic_istream<_CharT, _Traits>::sentry __sen(__is);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ _CharT* __s = __p;
+ const ctype<_CharT>& __ct = std::use_facet<ctype<_CharT> >(__is.getloc());
+ while (__s != __p + (__n - 1)) {
+ typename _Traits::int_type __i = __is.rdbuf()->sgetc();
+ if (_Traits::eq_int_type(__i, _Traits::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ _CharT __ch = _Traits::to_char_type(__i);
+ if (__ct.is(__ct.space, __ch))
+ break;
+ *__s++ = __ch;
+ __is.rdbuf()->sbumpc();
+ }
+ *__s = _CharT();
+ __is.width(0);
+ if (__s == __p)
+ __state |= ios_base::failbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ __is.__setstate_nothrow(__state);
+ if (__is.exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif
+ __is.setstate(__state);
+ }
+ return __is;
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _CharT, class _Traits, size_t _Np>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, _CharT (&__buf)[_Np]) {
+ size_t __n = _Np;
+ if (__is.width() > 0)
+ __n = std::min(size_t(__is.width()), _Np);
+ return std::__input_c_string(__is, __buf, __n);
+}
+
+template <class _Traits, size_t _Np>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<char, _Traits>&
+operator>>(basic_istream<char, _Traits>& __is, unsigned char (&__buf)[_Np]) {
+ return __is >> (char(&)[_Np])__buf;
+}
+
+template <class _Traits, size_t _Np>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<char, _Traits>&
+operator>>(basic_istream<char, _Traits>& __is, signed char (&__buf)[_Np]) {
+ return __is >> (char(&)[_Np])__buf;
+}
+
+#else
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, _CharT* __s) {
+ streamsize __n = __is.width();
+ if (__n <= 0)
+ __n = numeric_limits<streamsize>::max() / sizeof(_CharT) - 1;
+ return std::__input_c_string(__is, __s, size_t(__n));
+}
+
+template <class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<char, _Traits>&
+operator>>(basic_istream<char, _Traits>& __is, unsigned char* __s) {
+ return __is >> (char*)__s;
+}
+
+template <class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<char, _Traits>&
+operator>>(basic_istream<char, _Traits>& __is, signed char* __s) {
+ return __is >> (char*)__s;
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>& operator>>(basic_istream<_CharT, _Traits>& __is, _CharT& __c) {
+ ios_base::iostate __state = ios_base::goodbit;
+ typename basic_istream<_CharT, _Traits>::sentry __sen(__is);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ typename _Traits::int_type __i = __is.rdbuf()->sbumpc();
+ if (_Traits::eq_int_type(__i, _Traits::eof()))
+ __state |= ios_base::eofbit | ios_base::failbit;
+ else
+ __c = _Traits::to_char_type(__i);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ __is.__setstate_nothrow(__state);
+ if (__is.exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif
+ __is.setstate(__state);
+ }
+ return __is;
+}
+
+template <class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<char, _Traits>&
+operator>>(basic_istream<char, _Traits>& __is, unsigned char& __c) {
+ return __is >> (char&)__c;
+}
+
+template <class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<char, _Traits>&
+operator>>(basic_istream<char, _Traits>& __is, signed char& __c) {
+ return __is >> (char&)__c;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>&
+basic_istream<_CharT, _Traits>::operator>>(basic_streambuf<char_type, traits_type>* __sb) {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ sentry __s(*this, true);
+ if (__s) {
+ if (__sb) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ while (true) {
+ typename traits_type::int_type __i = this->rdbuf()->sgetc();
+ if (traits_type::eq_int_type(__i, _Traits::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ if (traits_type::eq_int_type(__sb->sputc(traits_type::to_char_type(__i)), traits_type::eof()))
+ break;
+ __inc_gcount();
+ this->rdbuf()->sbumpc();
+ }
+ if (__gc_ == 0)
+ __state |= ios_base::failbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ if (__gc_ == 0)
+ __state |= ios_base::failbit;
+
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::failbit || this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ } else {
+ __state |= ios_base::failbit;
+ }
+ this->setstate(__state);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+typename basic_istream<_CharT, _Traits>::int_type basic_istream<_CharT, _Traits>::get() {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ int_type __r = traits_type::eof();
+ sentry __s(*this, true);
+ if (__s) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ __r = this->rdbuf()->sbumpc();
+ if (traits_type::eq_int_type(__r, traits_type::eof()))
+ __state |= ios_base::failbit | ios_base::eofbit;
+ else
+ __gc_ = 1;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__setstate_nothrow(this->rdstate() | ios_base::badbit);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif
+ this->setstate(__state);
+ }
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::get(char_type* __s, streamsize __n, char_type __dlm) {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ sentry __sen(*this, true);
+ if (__sen) {
+ if (__n > 0) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ while (__gc_ < __n - 1) {
+ int_type __i = this->rdbuf()->sgetc();
+ if (traits_type::eq_int_type(__i, traits_type::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ char_type __ch = traits_type::to_char_type(__i);
+ if (traits_type::eq(__ch, __dlm))
+ break;
+ *__s++ = __ch;
+ __inc_gcount();
+ this->rdbuf()->sbumpc();
+ }
+ if (__gc_ == 0)
+ __state |= ios_base::failbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ if (__n > 0)
+ *__s = char_type();
+ throw;
+ }
+ }
+#endif
+ } else {
+ __state |= ios_base::failbit;
+ }
+
+ if (__n > 0)
+ *__s = char_type();
+ this->setstate(__state);
+ }
+ if (__n > 0)
+ *__s = char_type();
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>&
+basic_istream<_CharT, _Traits>::get(basic_streambuf<char_type, traits_type>& __sb, char_type __dlm) {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ while (true) {
+ typename traits_type::int_type __i = this->rdbuf()->sgetc();
+ if (traits_type::eq_int_type(__i, traits_type::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ char_type __ch = traits_type::to_char_type(__i);
+ if (traits_type::eq(__ch, __dlm))
+ break;
+ if (traits_type::eq_int_type(__sb.sputc(__ch), traits_type::eof()))
+ break;
+ __inc_gcount();
+ this->rdbuf()->sbumpc();
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ // according to the spec, exceptions here are caught but not rethrown
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (__gc_ == 0)
+ __state |= ios_base::failbit;
+ this->setstate(__state);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>&
+basic_istream<_CharT, _Traits>::getline(char_type* __s, streamsize __n, char_type __dlm) {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ while (true) {
+ typename traits_type::int_type __i = this->rdbuf()->sgetc();
+ if (traits_type::eq_int_type(__i, traits_type::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ char_type __ch = traits_type::to_char_type(__i);
+ if (traits_type::eq(__ch, __dlm)) {
+ this->rdbuf()->sbumpc();
+ __inc_gcount();
+ break;
+ }
+ if (__gc_ >= __n - 1) {
+ __state |= ios_base::failbit;
+ break;
+ }
+ *__s++ = __ch;
+ this->rdbuf()->sbumpc();
+ __inc_gcount();
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ if (__n > 0)
+ *__s = char_type();
+ if (__gc_ == 0)
+ __state |= ios_base::failbit;
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+ if (__n > 0)
+ *__s = char_type();
+ if (__gc_ == 0)
+ __state |= ios_base::failbit;
+ this->setstate(__state);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::ignore(streamsize __n, int_type __dlm) {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (__n == numeric_limits<streamsize>::max()) {
+ while (true) {
+ typename traits_type::int_type __i = this->rdbuf()->sbumpc();
+ if (traits_type::eq_int_type(__i, traits_type::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ __inc_gcount();
+ if (traits_type::eq_int_type(__i, __dlm))
+ break;
+ }
+ } else {
+ while (__gc_ < __n) {
+ typename traits_type::int_type __i = this->rdbuf()->sbumpc();
+ if (traits_type::eq_int_type(__i, traits_type::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ __inc_gcount();
+ if (traits_type::eq_int_type(__i, __dlm))
+ break;
+ }
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ this->setstate(__state);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+typename basic_istream<_CharT, _Traits>::int_type basic_istream<_CharT, _Traits>::peek() {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ int_type __r = traits_type::eof();
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __r = this->rdbuf()->sgetc();
+ if (traits_type::eq_int_type(__r, traits_type::eof()))
+ __state |= ios_base::eofbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ this->setstate(__state);
+ }
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::read(char_type* __s, streamsize __n) {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __gc_ = this->rdbuf()->sgetn(__s, __n);
+ if (__gc_ != __n)
+ __state |= ios_base::failbit | ios_base::eofbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ } else {
+ __state |= ios_base::failbit;
+ }
+ this->setstate(__state);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+streamsize basic_istream<_CharT, _Traits>::readsome(char_type* __s, streamsize __n) {
+ ios_base::iostate __state = ios_base::goodbit;
+ __gc_ = 0;
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ streamsize __c = this->rdbuf()->in_avail();
+ switch (__c) {
+ case -1:
+ __state |= ios_base::eofbit;
+ break;
+ case 0:
+ break;
+ default:
+ __n = std::min(__c, __n);
+ __gc_ = this->rdbuf()->sgetn(__s, __n);
+ if (__gc_ != __n)
+ __state |= ios_base::failbit | ios_base::eofbit;
+ break;
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ } else {
+ __state |= ios_base::failbit;
+ }
+ this->setstate(__state);
+ return __gc_;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::putback(char_type __c) {
+ ios_base::iostate __state = this->rdstate() & ~ios_base::eofbit;
+ __gc_ = 0;
+ this->clear(__state);
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (this->rdbuf() == nullptr || this->rdbuf()->sputbackc(__c) == traits_type::eof())
+ __state |= ios_base::badbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ } else {
+ __state |= ios_base::failbit;
+ }
+ this->setstate(__state);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::unget() {
+ ios_base::iostate __state = this->rdstate() & ~ios_base::eofbit;
+ __gc_ = 0;
+ this->clear(__state);
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (this->rdbuf() == nullptr || this->rdbuf()->sungetc() == traits_type::eof())
+ __state |= ios_base::badbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ } else {
+ __state |= ios_base::failbit;
+ }
+ this->setstate(__state);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+int basic_istream<_CharT, _Traits>::sync() {
+ ios_base::iostate __state = ios_base::goodbit;
+ sentry __sen(*this, true);
+ if (this->rdbuf() == nullptr)
+ return -1;
+
+ int __r = 0;
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (this->rdbuf()->pubsync() == -1) {
+ __state |= ios_base::badbit;
+ __r = -1;
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ this->setstate(__state);
+ }
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+typename basic_istream<_CharT, _Traits>::pos_type basic_istream<_CharT, _Traits>::tellg() {
+ ios_base::iostate __state = ios_base::goodbit;
+ pos_type __r(-1);
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __r = this->rdbuf()->pubseekoff(0, ios_base::cur, ios_base::in);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ this->setstate(__state);
+ }
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::seekg(pos_type __pos) {
+ ios_base::iostate __state = this->rdstate() & ~ios_base::eofbit;
+ this->clear(__state);
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (this->rdbuf()->pubseekpos(__pos, ios_base::in) == pos_type(-1))
+ __state |= ios_base::failbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ this->setstate(__state);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_istream<_CharT, _Traits>& basic_istream<_CharT, _Traits>::seekg(off_type __off, ios_base::seekdir __dir) {
+ ios_base::iostate __state = this->rdstate() & ~ios_base::eofbit;
+ this->clear(__state);
+ sentry __sen(*this, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ if (this->rdbuf()->pubseekoff(__off, __dir, ios_base::in) == pos_type(-1))
+ __state |= ios_base::failbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ this->__setstate_nothrow(__state);
+ if (this->exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ this->setstate(__state);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>& ws(basic_istream<_CharT, _Traits>& __is) {
+ ios_base::iostate __state = ios_base::goodbit;
+ typename basic_istream<_CharT, _Traits>::sentry __sen(__is, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ const ctype<_CharT>& __ct = std::use_facet<ctype<_CharT> >(__is.getloc());
+ while (true) {
+ typename _Traits::int_type __i = __is.rdbuf()->sgetc();
+ if (_Traits::eq_int_type(__i, _Traits::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ if (!__ct.is(__ct.space, _Traits::to_char_type(__i)))
+ break;
+ __is.rdbuf()->sbumpc();
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ __is.__setstate_nothrow(__state);
+ if (__is.exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __is.setstate(__state);
+ }
+ return __is;
+}
+
+template <class _Stream, class _Tp, class = void>
+struct __is_istreamable : false_type {};
+
+template <class _Stream, class _Tp>
+struct __is_istreamable<_Stream, _Tp, decltype(std::declval<_Stream>() >> std::declval<_Tp>(), void())> : true_type {};
+
+template <class _Stream,
+ class _Tp,
+ __enable_if_t< _And<is_base_of<ios_base, _Stream>, __is_istreamable<_Stream&, _Tp&&> >::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _Stream&& operator>>(_Stream&& __is, _Tp&& __x) {
+ __is >> std::forward<_Tp>(__x);
+ return std::move(__is);
+}
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_iostream
+ : public basic_istream<_CharT, _Traits>,
+ public basic_ostream<_CharT, _Traits> {
+public:
+ // types:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ // constructor/destructor
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 explicit basic_iostream(basic_streambuf<char_type, traits_type>* __sb)
+ : basic_istream<_CharT, _Traits>(__sb) {}
+
+ ~basic_iostream() override;
+
+protected:
+ inline _LIBCPP_HIDE_FROM_ABI basic_iostream(basic_iostream&& __rhs);
+
+ // assign/swap
+ inline _LIBCPP_HIDE_FROM_ABI basic_iostream& operator=(basic_iostream&& __rhs);
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void swap(basic_iostream& __rhs) {
+ basic_istream<char_type, traits_type>::swap(__rhs);
+ }
+};
+
+template <class _CharT, class _Traits>
+basic_iostream<_CharT, _Traits>::basic_iostream(basic_iostream&& __rhs)
+ : basic_istream<_CharT, _Traits>(std::move(__rhs)) {}
+
+template <class _CharT, class _Traits>
+basic_iostream<_CharT, _Traits>& basic_iostream<_CharT, _Traits>::operator=(basic_iostream&& __rhs) {
+ swap(__rhs);
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+basic_iostream<_CharT, _Traits>::~basic_iostream() {}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, basic_string<_CharT, _Traits, _Allocator>& __str) {
+ ios_base::iostate __state = ios_base::goodbit;
+ typename basic_istream<_CharT, _Traits>::sentry __sen(__is);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ __str.clear();
+ streamsize __n = __is.width();
+ if (__n <= 0)
+ __n = __str.max_size();
+ if (__n <= 0)
+ __n = numeric_limits<streamsize>::max();
+ streamsize __c = 0;
+ const ctype<_CharT>& __ct = std::use_facet<ctype<_CharT> >(__is.getloc());
+ while (__c < __n) {
+ typename _Traits::int_type __i = __is.rdbuf()->sgetc();
+ if (_Traits::eq_int_type(__i, _Traits::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ _CharT __ch = _Traits::to_char_type(__i);
+ if (__ct.is(__ct.space, __ch))
+ break;
+ __str.push_back(__ch);
+ ++__c;
+ __is.rdbuf()->sbumpc();
+ }
+ __is.width(0);
+ if (__c == 0)
+ __state |= ios_base::failbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ __is.__setstate_nothrow(__state);
+ if (__is.exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif
+ __is.setstate(__state);
+ }
+ return __is;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+getline(basic_istream<_CharT, _Traits>& __is, basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm) {
+ ios_base::iostate __state = ios_base::goodbit;
+ typename basic_istream<_CharT, _Traits>::sentry __sen(__is, true);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ __str.clear();
+ streamsize __extr = 0;
+ while (true) {
+ typename _Traits::int_type __i = __is.rdbuf()->sbumpc();
+ if (_Traits::eq_int_type(__i, _Traits::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ ++__extr;
+ _CharT __ch = _Traits::to_char_type(__i);
+ if (_Traits::eq(__ch, __dlm))
+ break;
+ __str.push_back(__ch);
+ if (__str.size() == __str.max_size()) {
+ __state |= ios_base::failbit;
+ break;
+ }
+ }
+ if (__extr == 0)
+ __state |= ios_base::failbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ __is.__setstate_nothrow(__state);
+ if (__is.exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif
+ __is.setstate(__state);
+ }
+ return __is;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+getline(basic_istream<_CharT, _Traits>& __is, basic_string<_CharT, _Traits, _Allocator>& __str) {
+ return std::getline(__is, __str, __is.widen('\n'));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+getline(basic_istream<_CharT, _Traits>&& __is, basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm) {
+ return std::getline(__is, __str, __dlm);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+getline(basic_istream<_CharT, _Traits>&& __is, basic_string<_CharT, _Traits, _Allocator>& __str) {
+ return std::getline(__is, __str, __is.widen('\n'));
+}
+
+template <class _CharT, class _Traits, size_t _Size>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, bitset<_Size>& __x) {
+ ios_base::iostate __state = ios_base::goodbit;
+ typename basic_istream<_CharT, _Traits>::sentry __sen(__is);
+ if (__sen) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif
+ basic_string<_CharT, _Traits> __str;
+ const ctype<_CharT>& __ct = std::use_facet<ctype<_CharT> >(__is.getloc());
+ size_t __c = 0;
+ _CharT __zero = __ct.widen('0');
+ _CharT __one = __ct.widen('1');
+ while (__c != _Size) {
+ typename _Traits::int_type __i = __is.rdbuf()->sgetc();
+ if (_Traits::eq_int_type(__i, _Traits::eof())) {
+ __state |= ios_base::eofbit;
+ break;
+ }
+ _CharT __ch = _Traits::to_char_type(__i);
+ if (!_Traits::eq(__ch, __zero) && !_Traits::eq(__ch, __one))
+ break;
+ __str.push_back(__ch);
+ ++__c;
+ __is.rdbuf()->sbumpc();
+ }
+ __x = bitset<_Size>(__str);
+ if (_Size > 0 && __c == 0)
+ __state |= ios_base::failbit;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __state |= ios_base::badbit;
+ __is.__setstate_nothrow(__state);
+ if (__is.exceptions() & ios_base::badbit) {
+ throw;
+ }
+ }
+#endif
+ __is.setstate(__state);
+ }
+ return __is;
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_istream<char>;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_istream<wchar_t>;
+#endif
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_iostream<char>;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <iosfwd>
+# include <ostream>
+# include <type_traits>
+#endif
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_ISTREAM
diff --git a/libcxx/include/__cxx03/iterator b/libcxx/include/__cxx03/iterator
new file mode 100644
index 00000000000000..fca75f0a19ed1b
--- /dev/null
+++ b/libcxx/include/__cxx03/iterator
@@ -0,0 +1,754 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_ITERATOR
+#define _LIBCPP_ITERATOR
+
+/*
+ iterator synopsis
+
+#include <concepts>
+
+namespace std
+{
+template<class> struct incrementable_traits; // since C++20
+template<class T>
+ using iter_difference_t = see below; // since C++20
+
+template<class> struct indirectly_readable_traits; // since C++20
+template<class T>
+ using iter_value_t = see below; // since C++20
+
+template<class Iterator>
+struct iterator_traits;
+
+template<class T>
+ requires is_object_v<T> // since C++20
+struct iterator_traits<T*>;
+
+template<dereferenceable T>
+ using iter_reference_t = decltype(*declval<T&>());
+
+namespace ranges::inline unspecified {
+ inline constexpr unspecified iter_move = unspecified; // since C++20, nodiscard as an extension
+}}
+
+template<dereferenceable T>
+ requires ...
+using iter_rvalue_reference_t = decltype(ranges::iter_move(declval<T&>())); // since C++20
+
+// [iterator.concepts], iterator concepts
+// [iterator.concept.readable], concept indirectly_readable
+template<class In>
+ concept indirectly_readable = see below; // since C++20
+
+template<indirectly_readable T>
+ using iter_common_reference_t =
+ common_reference_t<iter_reference_t<T>, iter_value_t<T>&>; // since C++20
+
+// [iterator.concept.writable], concept indirectly_writable
+template<class Out, class T>
+ concept indirectly_writable = see below; // since C++20
+
+// [iterator.concept.winc], concept weakly_incrementable
+template<class I>
+ concept weakly_incrementable = see below; // since C++20
+
+// [iterator.concept.inc], concept incrementable
+template<class I>
+ concept incrementable = see below; // since C++20
+
+// [iterator.concept.iterator], concept input_or_output_iterator
+ template<class I>
+ concept input_or_output_iterator = see below; // since C++20
+
+// [iterator.concept.sentinel], concept sentinel_for
+template<class S, class I>
+ concept sentinel_for = see below; // since C++20
+
+// [iterator.concept.sizedsentinel], concept sized_sentinel_for
+template<class S, class I>
+ inline constexpr bool disable_sized_sentinel_for = false;
+
+template<class S, class I>
+ concept sized_sentinel_for = see below;
+
+// [iterator.concept.input], concept input_iterator
+template<class I>
+ concept input_iterator = see below; // since C++20
+
+// [iterator.concept.output], concept output_iterator
+template<class I, class T>
+ concept output_iterator = see below; // since C++20
+
+// [iterator.concept.forward], concept forward_iterator
+template<class I>
+ concept forward_iterator = see below; // since C++20
+
+// [iterator.concept.bidir], concept bidirectional_iterator
+template<class I>
+ concept bidirectional_iterator = see below; // since C++20
+
+// [iterator.concept.random.access], concept random_access_iterator
+template<class I>
+ concept random_access_iterator = see below; // since C++20
+
+// [indirectcallable]
+// [indirectcallable.indirectinvocable]
+template<class F, class I>
+ concept indirectly_unary_invocable = see below; // since C++20
+
+template<class F, class I>
+ concept indirectly_regular_unary_invocable = see below; // since C++20
+
+template<class F, class I>
+ concept indirect_unary_predicate = see below; // since C++20
+
+template<class F, class I1, class I2>
+ concept indirect_binary_predicate = see below; // since C++20
+
+template<class F, class I1, class I2 = I1>
+ concept indirect_equivalence_relation = see below; // since C++20
+
+template<class F, class I1, class I2 = I1>
+ concept indirect_strict_weak_order = see below; // since C++20
+
+template<class F, class... Is>
+ using indirect_result_t = see below; // since C++20
+
+// [projected], projected
+template<indirectly_readable I, indirectly_regular_unary_invocable<I> Proj>
+ struct projected; // since C++20
+
+template<weakly_incrementable I, indirectly_regular_unary_invocable<I> Proj>
+ struct incrementable_traits<projected<I, Proj>>; // since C++20
+
+// [alg.req.ind.move], concept indirectly_movable
+template<class In, class Out>
+ concept indirectly_movable = see below; // since C++20
+
+template<class In, class Out>
+ concept indirectly_movable_storable = see below; // since C++20
+
+// [alg.req.ind.copy], concept indirectly_copyable
+template<class In, class Out>
+ concept indirectly_copyable = see below; // since C++20
+
+template<class In, class Out>
+ concept indirectly_copyable_storable = see below; // since C++20
+
+// [alg.req.ind.swap], concept indirectly_swappable
+template<class I1, class I2 = I1>
+ concept indirectly_swappable = see below; // since C++20
+
+template<class I1, class I2, class R, class P1 = identity,
+ class P2 = identity>
+ concept indirectly_comparable =
+ indirect_binary_predicate<R, projected<I1, P1>, projected<I2, P2>>; // since C++20
+
+// [alg.req.permutable], concept permutable
+template<class I>
+ concept permutable = see below; // since C++20
+
+ // [alg.req.mergeable], concept mergeable
+template<class I1, class I2, class Out,
+ class R = ranges::less, class P1 = identity, class P2 = identity>
+ concept mergeable = see below; // since C++20
+
+// [alg.req.sortable], concept sortable
+template<class I, class R = ranges::less, class P = identity>
+ concept sortable = see below; // since C++20
+
+template<input_or_output_iterator I, sentinel_for<I> S>
+ requires (!same_as<I, S> && copyable<I>)
+class common_iterator; // since C++20
+
+template<class Category, class T, class Distance = ptrdiff_t,
+ class Pointer = T*, class Reference = T&>
+struct iterator // deprecated in C++17
+{
+ typedef T value_type;
+ typedef Distance difference_type;
+ typedef Pointer pointer;
+ typedef Reference reference;
+ typedef Category iterator_category;
+};
+
+struct input_iterator_tag {};
+struct output_iterator_tag {};
+struct forward_iterator_tag : public input_iterator_tag {};
+struct bidirectional_iterator_tag : public forward_iterator_tag {};
+struct random_access_iterator_tag : public bidirectional_iterator_tag {};
+struct contiguous_iterator_tag : public random_access_iterator_tag {};
+
+// 27.4.3, iterator operations
+template <class InputIterator, class Distance> // constexpr in C++17
+ constexpr void advance(InputIterator& i, Distance n);
+
+template <class InputIterator> // constexpr in C++17
+ constexpr typename iterator_traits<InputIterator>::difference_type
+ distance(InputIterator first, InputIterator last);
+
+template <class InputIterator> // constexpr in C++17
+ constexpr InputIterator next(InputIterator x,
+typename iterator_traits<InputIterator>::difference_type n = 1);
+
+template <class BidirectionalIterator> // constexpr in C++17
+ constexpr BidirectionalIterator prev(BidirectionalIterator x,
+ typename iterator_traits<BidirectionalIterator>::difference_type n = 1);
+
+// [range.iter.ops], range iterator operations
+namespace ranges {
+ // [range.iter.op.advance], ranges::advance
+ template<input_or_output_iterator I>
+ constexpr void advance(I& i, iter_difference_t<I> n); // since C++20
+ template<input_or_output_iterator I, sentinel_for<I> S>
+ constexpr void advance(I& i, S bound); // since C++20
+ template<input_or_output_iterator I, sentinel_for<I> S>
+ constexpr iter_difference_t<I> advance(I& i, iter_difference_t<I> n, S bound); // since C++20
+}
+
+template <class Iterator>
+class reverse_iterator
+ : public iterator<typename iterator_traits<Iterator>::iterator_category, // until C++17
+ typename iterator_traits<Iterator>::value_type,
+ typename iterator_traits<Iterator>::difference_type,
+ typename iterator_traits<Iterator>::pointer,
+ typename iterator_traits<Iterator>::reference>
+{
+protected:
+ Iterator current;
+public:
+ using iterator_type = Iterator;
+ using iterator_concept = see below; // since C++20
+ using iterator_category = typename iterator_traits<Iterator>::iterator_category; // since C++17, until C++20
+ using iterator_category = see below; // since C++20
+ using value_type = typename iterator_traits<Iterator>::value_type; // since C++17, until C++20
+ using value_type = iter_value_t<Iterator>; // since C++20
+ using difference_type = typename iterator_traits<Iterator>::difference_type; // until C++20
+ using difference_type = iter_difference_t<Iterator>; // since C++20
+ using pointer = typename iterator_traits<Iterator>::pointer;
+ using reference = typename iterator_traits<Iterator>::reference; // until C++20
+ using reference = iter_reference_t<Iterator>; // since C++20
+
+ constexpr reverse_iterator();
+ constexpr explicit reverse_iterator(Iterator x);
+ template <class U> constexpr reverse_iterator(const reverse_iterator<U>& u);
+ template <class U> constexpr reverse_iterator& operator=(const reverse_iterator<U>& u);
+ constexpr Iterator base() const;
+ constexpr reference operator*() const;
+ constexpr pointer operator->() const; // until C++20
+ constexpr pointer operator->() const requires see below; // since C++20
+ constexpr reverse_iterator& operator++();
+ constexpr reverse_iterator operator++(int);
+ constexpr reverse_iterator& operator--();
+ constexpr reverse_iterator operator--(int);
+ constexpr reverse_iterator operator+ (difference_type n) const;
+ constexpr reverse_iterator& operator+=(difference_type n);
+ constexpr reverse_iterator operator- (difference_type n) const;
+ constexpr reverse_iterator& operator-=(difference_type n);
+ constexpr unspecified operator[](difference_type n) const;
+
+ friend constexpr iter_rvalue_reference_t<Iterator>
+ iter_move(const reverse_iterator& i) noexcept(see below);
+ template<indirectly_swappable<Iterator> Iterator2>
+ friend constexpr void
+ iter_swap(const reverse_iterator& x,
+ const reverse_iterator<Iterator2>& y) noexcept(see below);
+};
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator==(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator!=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator<(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator>(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator<=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator>=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
+
+template<class Iterator1, three_way_comparable_with<Iterator1> Iterator2>
+ constexpr compare_three_way_result_t<Iterator1, Iterator2>
+ operator<=>(const reverse_iterator<Iterator1>& x,
+ const reverse_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr auto
+operator-(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y)
+-> decltype(__y.base() - __x.base()); // constexpr in C++17
+
+template <class Iterator>
+constexpr reverse_iterator<Iterator>
+operator+(typename reverse_iterator<Iterator>::difference_type n,
+ const reverse_iterator<Iterator>& x); // constexpr in C++17
+
+template <class Iterator>
+constexpr reverse_iterator<Iterator> make_reverse_iterator(Iterator i); // C++14, constexpr in C++17
+
+template<class Iterator1, class Iterator2>
+ requires (!sized_sentinel_for<Iterator1, Iterator2>)
+ inline constexpr bool disable_sized_sentinel_for<reverse_iterator<Iterator1>,
+ reverse_iterator<Iterator2>> = true;
+
+template <class Container>
+class back_insert_iterator
+ : public iterator<output_iterator_tag, void, void, void, void> // until C++17
+{
+protected:
+ Container* container;
+public:
+ typedef Container container_type;
+ typedef void value_type;
+ typedef void difference_type; // until C++20
+ typedef ptrdiff_t difference_type; // since C++20
+ typedef void reference;
+ typedef void pointer;
+
+ explicit back_insert_iterator(Container& x); // constexpr in C++20
+ back_insert_iterator& operator=(const typename Container::value_type& value); // constexpr in C++20
+ back_insert_iterator& operator*(); // constexpr in C++20
+ back_insert_iterator& operator++(); // constexpr in C++20
+ back_insert_iterator operator++(int); // constexpr in C++20
+};
+
+template <class Container> back_insert_iterator<Container> back_inserter(Container& x); // constexpr in C++20
+
+template <class Container>
+class front_insert_iterator
+ : public iterator<output_iterator_tag, void, void, void, void> // until C++17
+{
+protected:
+ Container* container;
+public:
+ typedef Container container_type;
+ typedef void value_type;
+ typedef void difference_type; // until C++20
+ typedef ptrdiff_t difference_type; // since C++20
+ typedef void reference;
+ typedef void pointer;
+
+ explicit front_insert_iterator(Container& x); // constexpr in C++20
+ front_insert_iterator& operator=(const typename Container::value_type& value); // constexpr in C++20
+ front_insert_iterator& operator*(); // constexpr in C++20
+ front_insert_iterator& operator++(); // constexpr in C++20
+ front_insert_iterator operator++(int); // constexpr in C++20
+};
+
+template <class Container> front_insert_iterator<Container> front_inserter(Container& x); // constexpr in C++20
+
+template <class Container>
+class insert_iterator
+ : public iterator<output_iterator_tag, void, void, void, void> // until C++17
+{
+protected:
+ Container* container;
+ typename Container::iterator iter;
+public:
+ typedef Container container_type;
+ typedef void value_type;
+ typedef void difference_type; // until C++20
+ typedef ptrdiff_t difference_type; // since C++20
+ typedef void reference;
+ typedef void pointer;
+
+ insert_iterator(Container& x, typename Container::iterator i); // constexpr in C++20
+ insert_iterator& operator=(const typename Container::value_type& value); // constexpr in C++20
+ insert_iterator& operator*(); // constexpr in C++20
+ insert_iterator& operator++(); // constexpr in C++20
+ insert_iterator& operator++(int); // constexpr in C++20
+};
+
+template <class Container>
+insert_iterator<Container> inserter(Container& x, typename Container::iterator i); // until C++20
+template <class Container>
+constexpr insert_iterator<Container> inserter(Container& x, ranges::iterator_t<Container> i); // since C++20
+
+template <class Iterator>
+class move_iterator {
+public:
+ using iterator_type = Iterator;
+ using iterator_concept = see below; // From C++20
+ using iterator_category = see below; // not always present starting from C++20
+ using value_type = iter_value_t<Iterator>; // Until C++20, iterator_traits<Iterator>::value_type
+ using difference_type = iter_difference_t<Iterator>; // Until C++20, iterator_traits<Iterator>::difference_type;
+ using pointer = Iterator;
+ using reference = iter_rvalue_reference_t<Iterator>; // Until C++20, value_type&&
+
+ constexpr move_iterator(); // all the constexprs are in C++17
+ constexpr explicit move_iterator(Iterator i);
+ template <class U>
+ constexpr move_iterator(const move_iterator<U>& u);
+ template <class U>
+ constexpr move_iterator& operator=(const move_iterator<U>& u);
+
+ constexpr iterator_type base() const; // Until C++20
+ constexpr const Iterator& base() const & noexcept; // From C++20
+ constexpr Iterator base() &&; // From C++20
+
+ constexpr reference operator*() const;
+ constexpr pointer operator->() const; // Deprecated in C++20
+ constexpr move_iterator& operator++();
+ constexpr auto operator++(int); // Return type was move_iterator until C++20
+ constexpr move_iterator& operator--();
+ constexpr move_iterator operator--(int);
+ constexpr move_iterator operator+(difference_type n) const;
+ constexpr move_iterator& operator+=(difference_type n);
+ constexpr move_iterator operator-(difference_type n) const;
+ constexpr move_iterator& operator-=(difference_type n);
+ constexpr reference operator[](difference_type n) const; // Return type unspecified until C++20
+
+ template<sentinel_for<Iterator> S>
+ friend constexpr bool
+ operator==(const move_iterator& x, const move_sentinel<S>& y); // Since C++20
+ template<sized_sentinel_for<Iterator> S>
+ friend constexpr iter_difference_t<Iterator>
+ operator-(const move_sentinel<S>& x, const move_iterator& y); // Since C++20
+ template<sized_sentinel_for<Iterator> S>
+ friend constexpr iter_difference_t<Iterator>
+ operator-(const move_iterator& x, const move_sentinel<S>& y); // Since C++20
+ friend constexpr iter_rvalue_reference_t<Iterator>
+ iter_move(const move_iterator& i)
+ noexcept(noexcept(ranges::iter_move(i.current))); // Since C++20
+ template<indirectly_swappable<Iterator> Iterator2>
+ friend constexpr void
+ iter_swap(const move_iterator& x, const move_iterator<Iterator2>& y)
+ noexcept(noexcept(ranges::iter_swap(x.current, y.current))); // Since C++20
+
+private:
+ Iterator current; // exposition only
+};
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator==(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator!=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator<(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator<=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator>(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr bool // constexpr in C++17
+operator>=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
+
+template <class Iterator1, class Iterator2>
+constexpr auto // constexpr in C++17
+operator-(const move_iterator<Iterator1>& x,
+ const move_iterator<Iterator2>& y) -> decltype(x.base() - y.base());
+
+template <class Iterator>
+constexpr move_iterator<Iterator> operator+( // constexpr in C++17
+ typename move_iterator<Iterator>::difference_type n,
+ const move_iterator<Iterator>& x);
+
+template <class Iterator> // constexpr in C++17
+constexpr move_iterator<Iterator> make_move_iterator(const Iterator& i);
+
+template<class Iterator1, class Iterator2>
+ requires (!sized_sentinel_for<Iterator1, Iterator2>)
+ inline constexpr bool disable_sized_sentinel_for<move_iterator<Iterator1>, // since C++20
+ move_iterator<Iterator2>> = true;
+
+template<semiregular S>
+class move_sentinel {
+public:
+ constexpr move_sentinel();
+ constexpr explicit move_sentinel(S s);
+ template<class S2>
+ requires convertible_to<const S2&, S>
+ constexpr move_sentinel(const move_sentinel<S2>& s);
+ template<class S2>
+ requires assignable_from<S&, const S2&>
+ constexpr move_sentinel& operator=(const move_sentinel<S2>& s);
+
+ constexpr S base() const;
+private:
+ S last; // exposition only
+};
+
+// [default.sentinel], default sentinel
+struct default_sentinel_t;
+inline constexpr default_sentinel_t default_sentinel{};
+
+// [iterators.counted], counted iterators
+template<input_or_output_iterator I> class counted_iterator;
+
+template<input_iterator I>
+ requires see below
+ struct iterator_traits<counted_iterator<I>>;
+
+// [unreachable.sentinel], unreachable sentinel
+struct unreachable_sentinel_t;
+inline constexpr unreachable_sentinel_t unreachable_sentinel{};
+
+template <class T, class charT = char, class traits = char_traits<charT>, class Distance = ptrdiff_t>
+class istream_iterator
+ : public iterator<input_iterator_tag, T, Distance, const T*, const T&> // until C++17
+{
+public:
+ typedef input_iterator_tag iterator_category;
+ typedef T value_type;
+ typedef Distance difference_type;
+ typedef const T* pointer;
+ typedef const T& reference;
+
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef basic_istream<charT, traits> istream_type;
+
+ istream_iterator(); // constexpr since C++11
+ constexpr istream_iterator(default_sentinel_t); // since C++20
+ istream_iterator(istream_type& s);
+ istream_iterator(const istream_iterator& x);
+ ~istream_iterator();
+
+ const T& operator*() const;
+ const T* operator->() const;
+ istream_iterator& operator++();
+ istream_iterator operator++(int);
+ friend bool operator==(const istream_iterator& i, default_sentinel_t); // since C++20
+};
+
+template <class T, class charT, class traits, class Distance>
+bool operator==(const istream_iterator<T,charT,traits,Distance>& x,
+ const istream_iterator<T,charT,traits,Distance>& y);
+template <class T, class charT, class traits, class Distance>
+bool operator!=(const istream_iterator<T,charT,traits,Distance>& x,
+ const istream_iterator<T,charT,traits,Distance>& y); // until C++20
+
+template <class T, class charT = char, class traits = char_traits<charT> >
+class ostream_iterator
+ : public iterator<output_iterator_tag, void, void, void, void> // until C++17
+{
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+ typedef void difference_type; // until C++20
+ typedef ptrdiff_t difference_type; // since C++20
+ typedef void pointer;
+ typedef void reference;
+
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef basic_ostream<charT,traits> ostream_type;
+
+ ostream_iterator(ostream_type& s);
+ ostream_iterator(ostream_type& s, const charT* delimiter);
+ ostream_iterator(const ostream_iterator& x);
+ ~ostream_iterator();
+ ostream_iterator& operator=(const T& value);
+
+ ostream_iterator& operator*();
+ ostream_iterator& operator++();
+ ostream_iterator& operator++(int);
+};
+
+template<class charT, class traits = char_traits<charT> >
+class istreambuf_iterator
+ : public iterator<input_iterator_tag, charT, traits::off_type, unspecified, charT> // until C++17
+{
+public:
+ typedef input_iterator_tag iterator_category;
+ typedef charT value_type;
+ typedef traits::off_type difference_type;
+ typedef unspecified pointer;
+ typedef charT reference;
+
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef traits::int_type int_type;
+ typedef basic_streambuf<charT, traits> streambuf_type;
+ typedef basic_istream<charT, traits> istream_type;
+
+ istreambuf_iterator() noexcept; // constexpr since C++11
+ constexpr istreambuf_iterator(default_sentinel_t) noexcept; // since C++20
+ istreambuf_iterator(istream_type& s) noexcept;
+ istreambuf_iterator(streambuf_type* s) noexcept;
+ istreambuf_iterator(a-private-type) noexcept;
+
+ charT operator*() const;
+ pointer operator->() const;
+ istreambuf_iterator& operator++();
+ a-private-type operator++(int);
+
+ bool equal(const istreambuf_iterator& b) const;
+ friend bool operator==(const istreambuf_iterator& i, default_sentinel_t s); // since C++20
+};
+
+template <class charT, class traits>
+bool operator==(const istreambuf_iterator<charT,traits>& a,
+ const istreambuf_iterator<charT,traits>& b);
+template <class charT, class traits>
+bool operator!=(const istreambuf_iterator<charT,traits>& a,
+ const istreambuf_iterator<charT,traits>& b); // until C++20
+
+template <class charT, class traits = char_traits<charT> >
+class ostreambuf_iterator
+ : public iterator<output_iterator_tag, void, void, void, void> // until C++17
+{
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+ typedef void difference_type; // until C++20
+ typedef ptrdiff_t difference_type; // since C++20
+ typedef void pointer;
+ typedef void reference;
+
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef basic_streambuf<charT, traits> streambuf_type;
+ typedef basic_ostream<charT, traits> ostream_type;
+
+ ostreambuf_iterator(ostream_type& s) noexcept;
+ ostreambuf_iterator(streambuf_type* s) noexcept;
+ ostreambuf_iterator& operator=(charT c);
+ ostreambuf_iterator& operator*();
+ ostreambuf_iterator& operator++();
+ ostreambuf_iterator& operator++(int);
+ bool failed() const noexcept;
+};
+
+template <class C> constexpr auto begin(C& c) -> decltype(c.begin()); // constexpr since C++17
+template <class C> constexpr auto begin(const C& c) -> decltype(c.begin()); // constexpr since C++17
+template <class C> constexpr auto end(C& c) -> decltype(c.end()); // constexpr since C++17
+template <class C> constexpr auto end(const C& c) -> decltype(c.end()); // constexpr since C++17
+template <class T, size_t N> constexpr T* begin(T (&array)[N]) noexcept;
+template <class T, size_t N> constexpr T* end(T (&array)[N]) noexcept;
+
+template <class C> constexpr auto cbegin(const C& c) noexcept(see-below) -> decltype(std::begin(c)); // C++14
+template <class C> constexpr auto cend(const C& c) noexcept(see-below) -> decltype(std::end(c)); // C++14
+template <class C> constexpr auto rbegin(C& c) -> decltype(c.rbegin()); // C++14, constexpr since C++17
+template <class C> constexpr auto rbegin(const C& c) -> decltype(c.rbegin()); // C++14, constexpr since C++17
+template <class C> constexpr auto rend(C& c) -> decltype(c.rend()); // C++14, constexpr since C++17
+template <class C> constexpr auto rend(const C& c) -> decltype(c.rend()); // C++14, constexpr since C++17
+template <class E> constexpr reverse_iterator<const E*> rbegin(initializer_list<E> il); // C++14, constexpr since C++17
+template <class E> constexpr reverse_iterator<const E*> rend(initializer_list<E> il); // C++14, constexpr since C++17
+template <class T, size_t N> constexpr reverse_iterator<T*> rbegin(T (&array)[N]); // C++14, constexpr since C++17
+template <class T, size_t N> constexpr reverse_iterator<T*> rend(T (&array)[N]); // C++14, constexpr since C++17
+template <class C> constexpr auto crbegin(const C& c) -> decltype(std::rbegin(c)); // C++14, constexpr since C++17
+template <class C> constexpr auto crend(const C& c) -> decltype(std::rend(c)); // C++14, constexpr since C++17
+
+// 24.8, container access:
+template <class C> constexpr auto size(const C& c) -> decltype(c.size()); // C++17
+template <class T, size_t N> constexpr size_t size(const T (&array)[N]) noexcept; // C++17
+
+template <class C> constexpr auto ssize(const C& c)
+ -> common_type_t<ptrdiff_t, make_signed_t<decltype(c.size())>>; // C++20
+template <class T, ptrdiff_t> constexpr ptrdiff_t ssize(const T (&array)[N]) noexcept; // C++20
+
+template <class C> constexpr auto empty(const C& c) -> decltype(c.empty()); // C++17
+template <class T, size_t N> constexpr bool empty(const T (&array)[N]) noexcept; // C++17
+template <class E> constexpr bool empty(initializer_list<E> il) noexcept; // C++17
+template <class C> constexpr auto data(C& c) -> decltype(c.data()); // C++17
+template <class C> constexpr auto data(const C& c) -> decltype(c.data()); // C++17
+template <class T, size_t N> constexpr T* data(T (&array)[N]) noexcept; // C++17
+template <class E> constexpr const E* data(initializer_list<E> il) noexcept; // C++17
+
+} // std
+
+*/
+
+#include <__config>
+#include <__iterator/access.h>
+#include <__iterator/advance.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/distance.h>
+#include <__iterator/front_insert_iterator.h>
+#include <__iterator/insert_iterator.h>
+#include <__iterator/istream_iterator.h>
+#include <__iterator/istreambuf_iterator.h>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/move_iterator.h>
+#include <__iterator/next.h>
+#include <__iterator/ostream_iterator.h>
+#include <__iterator/ostreambuf_iterator.h>
+#include <__iterator/prev.h>
+#include <__iterator/reverse_iterator.h>
+#include <__iterator/wrap_iter.h>
+
+#if _LIBCPP_STD_VER >= 14
+# include <__iterator/reverse_access.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+# include <__iterator/data.h>
+# include <__iterator/empty.h>
+# include <__iterator/size.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+# include <__iterator/common_iterator.h>
+# include <__iterator/concepts.h>
+# include <__iterator/counted_iterator.h>
+# include <__iterator/default_sentinel.h>
+# include <__iterator/incrementable_traits.h>
+# include <__iterator/indirectly_comparable.h>
+# include <__iterator/iter_move.h>
+# include <__iterator/iter_swap.h>
+# include <__iterator/mergeable.h>
+# include <__iterator/move_sentinel.h>
+# include <__iterator/permutable.h>
+# include <__iterator/projected.h>
+# include <__iterator/readable_traits.h>
+# include <__iterator/sortable.h>
+# include <__iterator/unreachable_sentinel.h>
+#endif
+
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.synopsis]
+#include <compare>
+#include <concepts>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <variant>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdlib>
+# include <exception>
+# include <new>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_ITERATOR
diff --git a/libcxx/include/__cxx03/latch b/libcxx/include/__cxx03/latch
new file mode 100644
index 00000000000000..81d6028a9c2ce1
--- /dev/null
+++ b/libcxx/include/__cxx03/latch
@@ -0,0 +1,129 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_LATCH
+#define _LIBCPP_LATCH
+
+/*
+ latch synopsis
+
+namespace std
+{
+
+ class latch
+ {
+ public:
+ static constexpr ptrdiff_t max() noexcept;
+
+ constexpr explicit latch(ptrdiff_t __expected);
+ ~latch();
+
+ latch(const latch&) = delete;
+ latch& operator=(const latch&) = delete;
+
+ void count_down(ptrdiff_t __update = 1);
+ bool try_wait() const noexcept;
+ void wait() const;
+ void arrive_and_wait(ptrdiff_t __update = 1);
+
+ private:
+ ptrdiff_t __counter; // exposition only
+ };
+
+}
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+# include <__assert>
+# include <__atomic/atomic_base.h>
+# include <__atomic/atomic_sync.h>
+# include <__atomic/memory_order.h>
+# include <cstddef>
+# include <limits>
+# include <version>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+# if _LIBCPP_STD_VER >= 14
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_DEPRECATED_ATOMIC_SYNC latch {
+ __atomic_base<ptrdiff_t> __a_;
+
+public:
+ static _LIBCPP_HIDE_FROM_ABI constexpr ptrdiff_t max() noexcept { return numeric_limits<ptrdiff_t>::max(); }
+
+ inline _LIBCPP_HIDE_FROM_ABI constexpr explicit latch(ptrdiff_t __expected) : __a_(__expected) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __expected >= 0,
+ "latch::latch(ptrdiff_t): latch cannot be "
+ "initialized with a negative value");
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __expected <= max(),
+ "latch::latch(ptrdiff_t): latch cannot be "
+ "initialized with a value greater than max()");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~latch() = default;
+ latch(const latch&) = delete;
+ latch& operator=(const latch&) = delete;
+
+ inline _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void count_down(ptrdiff_t __update = 1) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(__update >= 0, "latch::count_down called with a negative value");
+ auto const __old = __a_.fetch_sub(__update, memory_order_release);
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __update <= __old,
+ "latch::count_down called with a value greater "
+ "than the internal counter");
+ if (__old == __update)
+ __a_.notify_all();
+ }
+ inline _LIBCPP_HIDE_FROM_ABI bool try_wait() const noexcept {
+ auto __value = __a_.load(memory_order_acquire);
+ return try_wait_impl(__value);
+ }
+ inline _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void wait() const {
+ std::__atomic_wait_unless(
+ __a_, [this](ptrdiff_t& __value) -> bool { return try_wait_impl(__value); }, memory_order_acquire);
+ }
+ inline _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void arrive_and_wait(ptrdiff_t __update = 1) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(__update >= 0, "latch::arrive_and_wait called with a negative value");
+ // other preconditions on __update are checked in count_down()
+
+ count_down(__update);
+ wait();
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI bool try_wait_impl(ptrdiff_t& __value) const noexcept { return __value == 0; }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+# endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_THREADS)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+#endif
+
+#endif //_LIBCPP_LATCH
diff --git a/libcxx/include/__cxx03/limits b/libcxx/include/__cxx03/limits
new file mode 100644
index 00000000000000..d55c7cd75f34fc
--- /dev/null
+++ b/libcxx/include/__cxx03/limits
@@ -0,0 +1,584 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_LIMITS
+#define _LIBCPP_LIMITS
+
+/*
+ limits synopsis
+
+namespace std
+{
+
+template<class T>
+class numeric_limits
+{
+public:
+ static constexpr bool is_specialized = false;
+ static constexpr T min() noexcept;
+ static constexpr T max() noexcept;
+ static constexpr T lowest() noexcept;
+
+ static constexpr int digits = 0;
+ static constexpr int digits10 = 0;
+ static constexpr int max_digits10 = 0;
+ static constexpr bool is_signed = false;
+ static constexpr bool is_integer = false;
+ static constexpr bool is_exact = false;
+ static constexpr int radix = 0;
+ static constexpr T epsilon() noexcept;
+ static constexpr T round_error() noexcept;
+
+ static constexpr int min_exponent = 0;
+ static constexpr int min_exponent10 = 0;
+ static constexpr int max_exponent = 0;
+ static constexpr int max_exponent10 = 0;
+
+ static constexpr bool has_infinity = false;
+ static constexpr bool has_quiet_NaN = false;
+ static constexpr bool has_signaling_NaN = false;
+ static constexpr float_denorm_style has_denorm = denorm_absent; // deprecated in C++23
+ static constexpr bool has_denorm_loss = false; // deprecated in C++23
+ static constexpr T infinity() noexcept;
+ static constexpr T quiet_NaN() noexcept;
+ static constexpr T signaling_NaN() noexcept;
+ static constexpr T denorm_min() noexcept;
+
+ static constexpr bool is_iec559 = false;
+ static constexpr bool is_bounded = false;
+ static constexpr bool is_modulo = false;
+
+ static constexpr bool traps = false;
+ static constexpr bool tinyness_before = false;
+ static constexpr float_round_style round_style = round_toward_zero;
+};
+
+enum float_round_style
+{
+ round_indeterminate = -1,
+ round_toward_zero = 0,
+ round_to_nearest = 1,
+ round_toward_infinity = 2,
+ round_toward_neg_infinity = 3
+};
+
+enum float_denorm_style // deprecated in C++23
+{
+ denorm_indeterminate = -1,
+ denorm_absent = 0,
+ denorm_present = 1
+};
+
+template<> class numeric_limits<cv bool>;
+
+template<> class numeric_limits<cv char>;
+template<> class numeric_limits<cv signed char>;
+template<> class numeric_limits<cv unsigned char>;
+template<> class numeric_limits<cv wchar_t>;
+template<> class numeric_limits<cv char8_t>; // C++20
+template<> class numeric_limits<cv char16_t>;
+template<> class numeric_limits<cv char32_t>;
+
+template<> class numeric_limits<cv short>;
+template<> class numeric_limits<cv int>;
+template<> class numeric_limits<cv long>;
+template<> class numeric_limits<cv long long>;
+template<> class numeric_limits<cv unsigned short>;
+template<> class numeric_limits<cv unsigned int>;
+template<> class numeric_limits<cv unsigned long>;
+template<> class numeric_limits<cv unsigned long long>;
+
+template<> class numeric_limits<cv float>;
+template<> class numeric_limits<cv double>;
+template<> class numeric_limits<cv long double>;
+
+} // std
+
+*/
+
+#include <__config>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/remove_cv.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+#include <version>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+enum float_round_style {
+ round_indeterminate = -1,
+ round_toward_zero = 0,
+ round_to_nearest = 1,
+ round_toward_infinity = 2,
+ round_toward_neg_infinity = 3
+};
+
+enum _LIBCPP_DEPRECATED_IN_CXX23 float_denorm_style {
+ denorm_indeterminate = -1,
+ denorm_absent = 0,
+ denorm_present = 1
+};
+
+template <class _Tp, bool = is_arithmetic<_Tp>::value>
+class __libcpp_numeric_limits {
+protected:
+ typedef _Tp type;
+
+ static _LIBCPP_CONSTEXPR const bool is_specialized = false;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type min() _NOEXCEPT { return type(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type max() _NOEXCEPT { return type(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type lowest() _NOEXCEPT { return type(); }
+
+ static _LIBCPP_CONSTEXPR const int digits = 0;
+ static _LIBCPP_CONSTEXPR const int digits10 = 0;
+ static _LIBCPP_CONSTEXPR const int max_digits10 = 0;
+ static _LIBCPP_CONSTEXPR const bool is_signed = false;
+ static _LIBCPP_CONSTEXPR const bool is_integer = false;
+ static _LIBCPP_CONSTEXPR const bool is_exact = false;
+ static _LIBCPP_CONSTEXPR const int radix = 0;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type epsilon() _NOEXCEPT { return type(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type round_error() _NOEXCEPT { return type(); }
+
+ static _LIBCPP_CONSTEXPR const int min_exponent = 0;
+ static _LIBCPP_CONSTEXPR const int min_exponent10 = 0;
+ static _LIBCPP_CONSTEXPR const int max_exponent = 0;
+ static _LIBCPP_CONSTEXPR const int max_exponent10 = 0;
+
+ static _LIBCPP_CONSTEXPR const bool has_infinity = false;
+ static _LIBCPP_CONSTEXPR const bool has_quiet_NaN = false;
+ static _LIBCPP_CONSTEXPR const bool has_signaling_NaN = false;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const float_denorm_style has_denorm = denorm_absent;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const bool has_denorm_loss = false;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type infinity() _NOEXCEPT { return type(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type quiet_NaN() _NOEXCEPT { return type(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type signaling_NaN() _NOEXCEPT { return type(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type denorm_min() _NOEXCEPT { return type(); }
+
+ static _LIBCPP_CONSTEXPR const bool is_iec559 = false;
+ static _LIBCPP_CONSTEXPR const bool is_bounded = false;
+ static _LIBCPP_CONSTEXPR const bool is_modulo = false;
+
+ static _LIBCPP_CONSTEXPR const bool traps = false;
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = false;
+ static _LIBCPP_CONSTEXPR const float_round_style round_style = round_toward_zero;
+};
+
+template <class _Tp, int __digits, bool _IsSigned>
+struct __libcpp_compute_min {
+ static _LIBCPP_CONSTEXPR const _Tp value = _Tp(_Tp(1) << __digits);
+};
+
+template <class _Tp, int __digits>
+struct __libcpp_compute_min<_Tp, __digits, false> {
+ static _LIBCPP_CONSTEXPR const _Tp value = _Tp(0);
+};
+
+template <class _Tp>
+class __libcpp_numeric_limits<_Tp, true> {
+protected:
+ typedef _Tp type;
+
+ static _LIBCPP_CONSTEXPR const bool is_specialized = true;
+
+ static _LIBCPP_CONSTEXPR const bool is_signed = type(-1) < type(0);
+ static _LIBCPP_CONSTEXPR const int digits = static_cast<int>(sizeof(type) * __CHAR_BIT__ - is_signed);
+ static _LIBCPP_CONSTEXPR const int digits10 = digits * 3 / 10;
+ static _LIBCPP_CONSTEXPR const int max_digits10 = 0;
+ static _LIBCPP_CONSTEXPR const type __min = __libcpp_compute_min<type, digits, is_signed>::value;
+ static _LIBCPP_CONSTEXPR const type __max = is_signed ? type(type(~0) ^ __min) : type(~0);
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type min() _NOEXCEPT { return __min; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type max() _NOEXCEPT { return __max; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type lowest() _NOEXCEPT { return min(); }
+
+ static _LIBCPP_CONSTEXPR const bool is_integer = true;
+ static _LIBCPP_CONSTEXPR const bool is_exact = true;
+ static _LIBCPP_CONSTEXPR const int radix = 2;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type epsilon() _NOEXCEPT { return type(0); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type round_error() _NOEXCEPT { return type(0); }
+
+ static _LIBCPP_CONSTEXPR const int min_exponent = 0;
+ static _LIBCPP_CONSTEXPR const int min_exponent10 = 0;
+ static _LIBCPP_CONSTEXPR const int max_exponent = 0;
+ static _LIBCPP_CONSTEXPR const int max_exponent10 = 0;
+
+ static _LIBCPP_CONSTEXPR const bool has_infinity = false;
+ static _LIBCPP_CONSTEXPR const bool has_quiet_NaN = false;
+ static _LIBCPP_CONSTEXPR const bool has_signaling_NaN = false;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const float_denorm_style has_denorm = denorm_absent;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const bool has_denorm_loss = false;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type infinity() _NOEXCEPT { return type(0); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type quiet_NaN() _NOEXCEPT { return type(0); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type signaling_NaN() _NOEXCEPT { return type(0); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type denorm_min() _NOEXCEPT { return type(0); }
+
+ static _LIBCPP_CONSTEXPR const bool is_iec559 = false;
+ static _LIBCPP_CONSTEXPR const bool is_bounded = true;
+ static _LIBCPP_CONSTEXPR const bool is_modulo = !std::is_signed<_Tp>::value;
+
+#if defined(__i386__) || defined(__x86_64__) || defined(__pnacl__) || defined(__wasm__)
+ static _LIBCPP_CONSTEXPR const bool traps = true;
+#else
+ static _LIBCPP_CONSTEXPR const bool traps = false;
+#endif
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = false;
+ static _LIBCPP_CONSTEXPR const float_round_style round_style = round_toward_zero;
+};
+
+template <>
+class __libcpp_numeric_limits<bool, true> {
+protected:
+ typedef bool type;
+
+ static _LIBCPP_CONSTEXPR const bool is_specialized = true;
+
+ static _LIBCPP_CONSTEXPR const bool is_signed = false;
+ static _LIBCPP_CONSTEXPR const int digits = 1;
+ static _LIBCPP_CONSTEXPR const int digits10 = 0;
+ static _LIBCPP_CONSTEXPR const int max_digits10 = 0;
+ static _LIBCPP_CONSTEXPR const type __min = false;
+ static _LIBCPP_CONSTEXPR const type __max = true;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type min() _NOEXCEPT { return __min; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type max() _NOEXCEPT { return __max; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type lowest() _NOEXCEPT { return min(); }
+
+ static _LIBCPP_CONSTEXPR const bool is_integer = true;
+ static _LIBCPP_CONSTEXPR const bool is_exact = true;
+ static _LIBCPP_CONSTEXPR const int radix = 2;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type epsilon() _NOEXCEPT { return type(0); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type round_error() _NOEXCEPT { return type(0); }
+
+ static _LIBCPP_CONSTEXPR const int min_exponent = 0;
+ static _LIBCPP_CONSTEXPR const int min_exponent10 = 0;
+ static _LIBCPP_CONSTEXPR const int max_exponent = 0;
+ static _LIBCPP_CONSTEXPR const int max_exponent10 = 0;
+
+ static _LIBCPP_CONSTEXPR const bool has_infinity = false;
+ static _LIBCPP_CONSTEXPR const bool has_quiet_NaN = false;
+ static _LIBCPP_CONSTEXPR const bool has_signaling_NaN = false;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const float_denorm_style has_denorm = denorm_absent;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const bool has_denorm_loss = false;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type infinity() _NOEXCEPT { return type(0); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type quiet_NaN() _NOEXCEPT { return type(0); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type signaling_NaN() _NOEXCEPT { return type(0); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type denorm_min() _NOEXCEPT { return type(0); }
+
+ static _LIBCPP_CONSTEXPR const bool is_iec559 = false;
+ static _LIBCPP_CONSTEXPR const bool is_bounded = true;
+ static _LIBCPP_CONSTEXPR const bool is_modulo = false;
+
+ static _LIBCPP_CONSTEXPR const bool traps = false;
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = false;
+ static _LIBCPP_CONSTEXPR const float_round_style round_style = round_toward_zero;
+};
+
+template <>
+class __libcpp_numeric_limits<float, true> {
+protected:
+ typedef float type;
+
+ static _LIBCPP_CONSTEXPR const bool is_specialized = true;
+
+ static _LIBCPP_CONSTEXPR const bool is_signed = true;
+ static _LIBCPP_CONSTEXPR const int digits = __FLT_MANT_DIG__;
+ static _LIBCPP_CONSTEXPR const int digits10 = __FLT_DIG__;
+ static _LIBCPP_CONSTEXPR const int max_digits10 = 2 + (digits * 30103l) / 100000l;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type min() _NOEXCEPT { return __FLT_MIN__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type max() _NOEXCEPT { return __FLT_MAX__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type lowest() _NOEXCEPT { return -max(); }
+
+ static _LIBCPP_CONSTEXPR const bool is_integer = false;
+ static _LIBCPP_CONSTEXPR const bool is_exact = false;
+ static _LIBCPP_CONSTEXPR const int radix = __FLT_RADIX__;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type epsilon() _NOEXCEPT { return __FLT_EPSILON__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type round_error() _NOEXCEPT { return 0.5F; }
+
+ static _LIBCPP_CONSTEXPR const int min_exponent = __FLT_MIN_EXP__;
+ static _LIBCPP_CONSTEXPR const int min_exponent10 = __FLT_MIN_10_EXP__;
+ static _LIBCPP_CONSTEXPR const int max_exponent = __FLT_MAX_EXP__;
+ static _LIBCPP_CONSTEXPR const int max_exponent10 = __FLT_MAX_10_EXP__;
+
+ static _LIBCPP_CONSTEXPR const bool has_infinity = true;
+ static _LIBCPP_CONSTEXPR const bool has_quiet_NaN = true;
+ static _LIBCPP_CONSTEXPR const bool has_signaling_NaN = true;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const float_denorm_style has_denorm = denorm_present;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const bool has_denorm_loss = false;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type infinity() _NOEXCEPT {
+ return __builtin_huge_valf();
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type quiet_NaN() _NOEXCEPT {
+ return __builtin_nanf("");
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type signaling_NaN() _NOEXCEPT {
+ return __builtin_nansf("");
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type denorm_min() _NOEXCEPT {
+ return __FLT_DENORM_MIN__;
+ }
+
+ static _LIBCPP_CONSTEXPR const bool is_iec559 = true;
+ static _LIBCPP_CONSTEXPR const bool is_bounded = true;
+ static _LIBCPP_CONSTEXPR const bool is_modulo = false;
+
+ static _LIBCPP_CONSTEXPR const bool traps = false;
+#if (defined(__arm__) || defined(__aarch64__))
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = true;
+#else
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = false;
+#endif
+ static _LIBCPP_CONSTEXPR const float_round_style round_style = round_to_nearest;
+};
+
+template <>
+class __libcpp_numeric_limits<double, true> {
+protected:
+ typedef double type;
+
+ static _LIBCPP_CONSTEXPR const bool is_specialized = true;
+
+ static _LIBCPP_CONSTEXPR const bool is_signed = true;
+ static _LIBCPP_CONSTEXPR const int digits = __DBL_MANT_DIG__;
+ static _LIBCPP_CONSTEXPR const int digits10 = __DBL_DIG__;
+ static _LIBCPP_CONSTEXPR const int max_digits10 = 2 + (digits * 30103l) / 100000l;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type min() _NOEXCEPT { return __DBL_MIN__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type max() _NOEXCEPT { return __DBL_MAX__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type lowest() _NOEXCEPT { return -max(); }
+
+ static _LIBCPP_CONSTEXPR const bool is_integer = false;
+ static _LIBCPP_CONSTEXPR const bool is_exact = false;
+ static _LIBCPP_CONSTEXPR const int radix = __FLT_RADIX__;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type epsilon() _NOEXCEPT { return __DBL_EPSILON__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type round_error() _NOEXCEPT { return 0.5; }
+
+ static _LIBCPP_CONSTEXPR const int min_exponent = __DBL_MIN_EXP__;
+ static _LIBCPP_CONSTEXPR const int min_exponent10 = __DBL_MIN_10_EXP__;
+ static _LIBCPP_CONSTEXPR const int max_exponent = __DBL_MAX_EXP__;
+ static _LIBCPP_CONSTEXPR const int max_exponent10 = __DBL_MAX_10_EXP__;
+
+ static _LIBCPP_CONSTEXPR const bool has_infinity = true;
+ static _LIBCPP_CONSTEXPR const bool has_quiet_NaN = true;
+ static _LIBCPP_CONSTEXPR const bool has_signaling_NaN = true;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const float_denorm_style has_denorm = denorm_present;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const bool has_denorm_loss = false;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type infinity() _NOEXCEPT {
+ return __builtin_huge_val();
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type quiet_NaN() _NOEXCEPT {
+ return __builtin_nan("");
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type signaling_NaN() _NOEXCEPT {
+ return __builtin_nans("");
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type denorm_min() _NOEXCEPT {
+ return __DBL_DENORM_MIN__;
+ }
+
+ static _LIBCPP_CONSTEXPR const bool is_iec559 = true;
+ static _LIBCPP_CONSTEXPR const bool is_bounded = true;
+ static _LIBCPP_CONSTEXPR const bool is_modulo = false;
+
+ static _LIBCPP_CONSTEXPR const bool traps = false;
+#if (defined(__arm__) || defined(__aarch64__))
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = true;
+#else
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = false;
+#endif
+ static _LIBCPP_CONSTEXPR const float_round_style round_style = round_to_nearest;
+};
+
+template <>
+class __libcpp_numeric_limits<long double, true> {
+protected:
+ typedef long double type;
+
+ static _LIBCPP_CONSTEXPR const bool is_specialized = true;
+
+ static _LIBCPP_CONSTEXPR const bool is_signed = true;
+ static _LIBCPP_CONSTEXPR const int digits = __LDBL_MANT_DIG__;
+ static _LIBCPP_CONSTEXPR const int digits10 = __LDBL_DIG__;
+ static _LIBCPP_CONSTEXPR const int max_digits10 = 2 + (digits * 30103l) / 100000l;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type min() _NOEXCEPT { return __LDBL_MIN__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type max() _NOEXCEPT { return __LDBL_MAX__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type lowest() _NOEXCEPT { return -max(); }
+
+ static _LIBCPP_CONSTEXPR const bool is_integer = false;
+ static _LIBCPP_CONSTEXPR const bool is_exact = false;
+ static _LIBCPP_CONSTEXPR const int radix = __FLT_RADIX__;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type epsilon() _NOEXCEPT { return __LDBL_EPSILON__; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type round_error() _NOEXCEPT { return 0.5L; }
+
+ static _LIBCPP_CONSTEXPR const int min_exponent = __LDBL_MIN_EXP__;
+ static _LIBCPP_CONSTEXPR const int min_exponent10 = __LDBL_MIN_10_EXP__;
+ static _LIBCPP_CONSTEXPR const int max_exponent = __LDBL_MAX_EXP__;
+ static _LIBCPP_CONSTEXPR const int max_exponent10 = __LDBL_MAX_10_EXP__;
+
+ static _LIBCPP_CONSTEXPR const bool has_infinity = true;
+ static _LIBCPP_CONSTEXPR const bool has_quiet_NaN = true;
+ static _LIBCPP_CONSTEXPR const bool has_signaling_NaN = true;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const float_denorm_style has_denorm = denorm_present;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const bool has_denorm_loss = false;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type infinity() _NOEXCEPT {
+ return __builtin_huge_vall();
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type quiet_NaN() _NOEXCEPT {
+ return __builtin_nanl("");
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type signaling_NaN() _NOEXCEPT {
+ return __builtin_nansl("");
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type denorm_min() _NOEXCEPT {
+ return __LDBL_DENORM_MIN__;
+ }
+
+#if defined(__powerpc__) && defined(__LONG_DOUBLE_IBM128__)
+ static _LIBCPP_CONSTEXPR const bool is_iec559 = false;
+#else
+ static _LIBCPP_CONSTEXPR const bool is_iec559 = true;
+#endif
+ static _LIBCPP_CONSTEXPR const bool is_bounded = true;
+ static _LIBCPP_CONSTEXPR const bool is_modulo = false;
+
+ static _LIBCPP_CONSTEXPR const bool traps = false;
+#if (defined(__arm__) || defined(__aarch64__))
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = true;
+#else
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = false;
+#endif
+ static _LIBCPP_CONSTEXPR const float_round_style round_style = round_to_nearest;
+};
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS numeric_limits : private __libcpp_numeric_limits<_Tp> {
+ typedef __libcpp_numeric_limits<_Tp> __base;
+ typedef typename __base::type type;
+
+public:
+ static _LIBCPP_CONSTEXPR const bool is_specialized = __base::is_specialized;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type min() _NOEXCEPT { return __base::min(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type max() _NOEXCEPT { return __base::max(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type lowest() _NOEXCEPT { return __base::lowest(); }
+
+ static _LIBCPP_CONSTEXPR const int digits = __base::digits;
+ static _LIBCPP_CONSTEXPR const int digits10 = __base::digits10;
+ static _LIBCPP_CONSTEXPR const int max_digits10 = __base::max_digits10;
+ static _LIBCPP_CONSTEXPR const bool is_signed = __base::is_signed;
+ static _LIBCPP_CONSTEXPR const bool is_integer = __base::is_integer;
+ static _LIBCPP_CONSTEXPR const bool is_exact = __base::is_exact;
+ static _LIBCPP_CONSTEXPR const int radix = __base::radix;
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type epsilon() _NOEXCEPT {
+ return __base::epsilon();
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type round_error() _NOEXCEPT {
+ return __base::round_error();
+ }
+
+ static _LIBCPP_CONSTEXPR const int min_exponent = __base::min_exponent;
+ static _LIBCPP_CONSTEXPR const int min_exponent10 = __base::min_exponent10;
+ static _LIBCPP_CONSTEXPR const int max_exponent = __base::max_exponent;
+ static _LIBCPP_CONSTEXPR const int max_exponent10 = __base::max_exponent10;
+
+ static _LIBCPP_CONSTEXPR const bool has_infinity = __base::has_infinity;
+ static _LIBCPP_CONSTEXPR const bool has_quiet_NaN = __base::has_quiet_NaN;
+ static _LIBCPP_CONSTEXPR const bool has_signaling_NaN = __base::has_signaling_NaN;
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const float_denorm_style has_denorm = __base::has_denorm;
+ static _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_CONSTEXPR const bool has_denorm_loss = __base::has_denorm_loss;
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type infinity() _NOEXCEPT {
+ return __base::infinity();
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type quiet_NaN() _NOEXCEPT {
+ return __base::quiet_NaN();
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type signaling_NaN() _NOEXCEPT {
+ return __base::signaling_NaN();
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR type denorm_min() _NOEXCEPT {
+ return __base::denorm_min();
+ }
+
+ static _LIBCPP_CONSTEXPR const bool is_iec559 = __base::is_iec559;
+ static _LIBCPP_CONSTEXPR const bool is_bounded = __base::is_bounded;
+ static _LIBCPP_CONSTEXPR const bool is_modulo = __base::is_modulo;
+
+ static _LIBCPP_CONSTEXPR const bool traps = __base::traps;
+ static _LIBCPP_CONSTEXPR const bool tinyness_before = __base::tinyness_before;
+ static _LIBCPP_CONSTEXPR const float_round_style round_style = __base::round_style;
+};
+
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::is_specialized;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const int numeric_limits<_Tp>::digits;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const int numeric_limits<_Tp>::digits10;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const int numeric_limits<_Tp>::max_digits10;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::is_signed;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::is_integer;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::is_exact;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const int numeric_limits<_Tp>::radix;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const int numeric_limits<_Tp>::min_exponent;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const int numeric_limits<_Tp>::min_exponent10;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const int numeric_limits<_Tp>::max_exponent;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const int numeric_limits<_Tp>::max_exponent10;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::has_infinity;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::has_quiet_NaN;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::has_signaling_NaN;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const float_denorm_style numeric_limits<_Tp>::has_denorm;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::has_denorm_loss;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::is_iec559;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::is_bounded;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::is_modulo;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::traps;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const bool numeric_limits<_Tp>::tinyness_before;
+template <class _Tp>
+_LIBCPP_CONSTEXPR const float_round_style numeric_limits<_Tp>::round_style;
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS numeric_limits<const _Tp> : public numeric_limits<_Tp> {};
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS numeric_limits<volatile _Tp> : public numeric_limits<_Tp> {};
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS numeric_limits<const volatile _Tp> : public numeric_limits<_Tp> {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_LIMITS
diff --git a/libcxx/include/__cxx03/list b/libcxx/include/__cxx03/list
new file mode 100644
index 00000000000000..929c84de7be449
--- /dev/null
+++ b/libcxx/include/__cxx03/list
@@ -0,0 +1,1743 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_LIST
+#define _LIBCPP_LIST
+
+/*
+ list synopsis
+
+namespace std
+{
+
+template <class T, class Alloc = allocator<T> >
+class list
+{
+public:
+
+ // types:
+ typedef T value_type;
+ typedef Alloc allocator_type;
+ typedef typename allocator_type::reference reference;
+ typedef typename allocator_type::const_reference const_reference;
+ typedef typename allocator_type::pointer pointer;
+ typedef typename allocator_type::const_pointer const_pointer;
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef implementation-defined size_type;
+ typedef implementation-defined difference_type;
+ typedef reverse_iterator<iterator> reverse_iterator;
+ typedef reverse_iterator<const_iterator> const_reverse_iterator;
+
+ list()
+ noexcept(is_nothrow_default_constructible<allocator_type>::value);
+ explicit list(const allocator_type& a);
+ explicit list(size_type n);
+ explicit list(size_type n, const allocator_type& a); // C++14
+ list(size_type n, const value_type& value);
+ list(size_type n, const value_type& value, const allocator_type& a);
+ template <class Iter>
+ list(Iter first, Iter last);
+ template <class Iter>
+ list(Iter first, Iter last, const allocator_type& a);
+ template<container-compatible-range<T> R>
+ list(from_range_t, R&& rg, const Allocator& = Allocator()); // C++23
+ list(const list& x);
+ list(const list&, const allocator_type& a);
+ list(list&& x)
+ noexcept(is_nothrow_move_constructible<allocator_type>::value);
+ list(list&&, const allocator_type& a);
+ list(initializer_list<value_type>);
+ list(initializer_list<value_type>, const allocator_type& a);
+
+ ~list();
+
+ list& operator=(const list& x);
+ list& operator=(list&& x)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value);
+ list& operator=(initializer_list<value_type>);
+ template <class Iter>
+ void assign(Iter first, Iter last);
+ template<container-compatible-range<T> R>
+ void assign_range(R&& rg); // C++23
+ void assign(size_type n, const value_type& t);
+ void assign(initializer_list<value_type>);
+
+ allocator_type get_allocator() const noexcept;
+
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+ reverse_iterator rbegin() noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ reverse_iterator rend() noexcept;
+ const_reverse_iterator rend() const noexcept;
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ reference front();
+ const_reference front() const;
+ reference back();
+ const_reference back() const;
+
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ template <class... Args>
+ reference emplace_front(Args&&... args); // reference in C++17
+ void pop_front();
+ template <class... Args>
+ reference emplace_back(Args&&... args); // reference in C++17
+ void pop_back();
+ void push_front(const value_type& x);
+ void push_front(value_type&& x);
+ template<container-compatible-range<T> R>
+ void prepend_range(R&& rg); // C++23
+ void push_back(const value_type& x);
+ void push_back(value_type&& x);
+ template<container-compatible-range<T> R>
+ void append_range(R&& rg); // C++23
+ template <class... Args>
+ iterator emplace(const_iterator position, Args&&... args);
+ iterator insert(const_iterator position, const value_type& x);
+ iterator insert(const_iterator position, value_type&& x);
+ iterator insert(const_iterator position, size_type n, const value_type& x);
+ template <class Iter>
+ iterator insert(const_iterator position, Iter first, Iter last);
+ template<container-compatible-range<T> R>
+ iterator insert_range(const_iterator position, R&& rg); // C++23
+ iterator insert(const_iterator position, initializer_list<value_type> il);
+
+ iterator erase(const_iterator position);
+ iterator erase(const_iterator position, const_iterator last);
+
+ void resize(size_type sz);
+ void resize(size_type sz, const value_type& c);
+
+ void swap(list&)
+ noexcept(allocator_traits<allocator_type>::is_always_equal::value); // C++17
+ void clear() noexcept;
+
+ void splice(const_iterator position, list& x);
+ void splice(const_iterator position, list&& x);
+ void splice(const_iterator position, list& x, const_iterator i);
+ void splice(const_iterator position, list&& x, const_iterator i);
+ void splice(const_iterator position, list& x, const_iterator first,
+ const_iterator last);
+ void splice(const_iterator position, list&& x, const_iterator first,
+ const_iterator last);
+
+ size_type remove(const value_type& value); // void before C++20
+ template <class Pred>
+ size_type remove_if(Pred pred); // void before C++20
+ size_type unique(); // void before C++20
+ template <class BinaryPredicate>
+ size_type unique(BinaryPredicate binary_pred); // void before C++20
+ void merge(list& x);
+ void merge(list&& x);
+ template <class Compare>
+ void merge(list& x, Compare comp);
+ template <class Compare>
+ void merge(list&& x, Compare comp);
+ void sort();
+ template <class Compare>
+ void sort(Compare comp);
+ void reverse() noexcept;
+};
+
+
+template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+ list(InputIterator, InputIterator, Allocator = Allocator())
+ -> list<typename iterator_traits<InputIterator>::value_type, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator = allocator<ranges::range_value_t<R>>>
+ list(from_range_t, R&&, Allocator = Allocator())
+ -> list<ranges::range_value_t<R>, Allocator>; // C++23
+
+template <class T, class Alloc>
+ bool operator==(const list<T,Alloc>& x, const list<T,Alloc>& y);
+template <class T, class Alloc>
+ bool operator< (const list<T,Alloc>& x, const list<T,Alloc>& y); // removed in C++20
+template <class T, class Alloc>
+ bool operator!=(const list<T,Alloc>& x, const list<T,Alloc>& y); // removed in C++20
+template <class T, class Alloc>
+ bool operator> (const list<T,Alloc>& x, const list<T,Alloc>& y); // removed in C++20
+template <class T, class Alloc>
+ bool operator>=(const list<T,Alloc>& x, const list<T,Alloc>& y); // removed in C++20
+template <class T, class Alloc>
+ bool operator<=(const list<T,Alloc>& x, const list<T,Alloc>& y); // removed in C++20
+template<class T, class Allocator>
+ synth-three-way-result<T> operator<=>(const list<T, Allocator>& x,
+ const list<T, Allocator>& y); // since C++20
+
+template <class T, class Alloc>
+ void swap(list<T,Alloc>& x, list<T,Alloc>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class T, class Allocator, class U>
+ typename list<T, Allocator>::size_type
+ erase(list<T, Allocator>& c, const U& value); // since C++20
+template <class T, class Allocator, class Predicate>
+ typename list<T, Allocator>::size_type
+ erase_if(list<T, Allocator>& c, Predicate pred); // since C++20
+
+} // std
+
+*/
+
+#include <__algorithm/comp.h>
+#include <__algorithm/equal.h>
+#include <__algorithm/lexicographical_compare.h>
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__config>
+#include <__format/enable_insertable.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/move_iterator.h>
+#include <__iterator/next.h>
+#include <__iterator/prev.h>
+#include <__iterator/reverse_iterator.h>
+#include <__memory/addressof.h>
+#include <__memory/allocation_guard.h>
+#include <__memory/allocator.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/compressed_pair.h>
+#include <__memory/construct_at.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/swap_allocator.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_allocator.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <cstring>
+#include <limits>
+#include <new> // __launder
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [list.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _VoidPtr>
+struct __list_node;
+template <class _Tp, class _VoidPtr>
+struct __list_node_base;
+
+template <class _Tp, class _VoidPtr>
+struct __list_node_pointer_traits {
+ typedef __rebind_pointer_t<_VoidPtr, __list_node<_Tp, _VoidPtr> > __node_pointer;
+ typedef __rebind_pointer_t<_VoidPtr, __list_node_base<_Tp, _VoidPtr> > __base_pointer;
+
+#if defined(_LIBCPP_ABI_LIST_REMOVE_NODE_POINTER_UB)
+ typedef __base_pointer __link_pointer;
+#else
+ typedef __conditional_t<is_pointer<_VoidPtr>::value, __base_pointer, __node_pointer> __link_pointer;
+#endif
+
+ typedef __conditional_t<is_same<__link_pointer, __node_pointer>::value, __base_pointer, __node_pointer>
+ __non_link_pointer;
+
+ static _LIBCPP_HIDE_FROM_ABI __link_pointer __unsafe_link_pointer_cast(__link_pointer __p) { return __p; }
+
+ static _LIBCPP_HIDE_FROM_ABI __link_pointer __unsafe_link_pointer_cast(__non_link_pointer __p) {
+ return static_cast<__link_pointer>(static_cast<_VoidPtr>(__p));
+ }
+};
+
+template <class _Tp, class _VoidPtr>
+struct __list_node_base {
+ typedef __list_node_pointer_traits<_Tp, _VoidPtr> _NodeTraits;
+ typedef typename _NodeTraits::__node_pointer __node_pointer;
+ typedef typename _NodeTraits::__base_pointer __base_pointer;
+ typedef typename _NodeTraits::__link_pointer __link_pointer;
+
+ __link_pointer __prev_;
+ __link_pointer __next_;
+
+ _LIBCPP_HIDE_FROM_ABI __list_node_base()
+ : __prev_(_NodeTraits::__unsafe_link_pointer_cast(__self())),
+ __next_(_NodeTraits::__unsafe_link_pointer_cast(__self())) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit __list_node_base(__link_pointer __prev, __link_pointer __next)
+ : __prev_(__prev), __next_(__next) {}
+
+ _LIBCPP_HIDE_FROM_ABI __base_pointer __self() { return pointer_traits<__base_pointer>::pointer_to(*this); }
+
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __as_node() { return static_cast<__node_pointer>(__self()); }
+};
+
+template <class _Tp, class _VoidPtr>
+struct __list_node : public __list_node_base<_Tp, _VoidPtr> {
+ // We allow starting the lifetime of nodes without initializing the value held by the node,
+ // since that is handled by the list itself in order to be allocator-aware.
+#ifndef _LIBCPP_CXX03_LANG
+
+private:
+ union {
+ _Tp __value_;
+ };
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _Tp& __get_value() { return __value_; }
+#else
+
+private:
+ _ALIGNAS_TYPE(_Tp) char __buffer_[sizeof(_Tp)];
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _Tp& __get_value() { return *std::__launder(reinterpret_cast<_Tp*>(&__buffer_)); }
+#endif
+
+ typedef __list_node_base<_Tp, _VoidPtr> __base;
+ typedef typename __base::__link_pointer __link_pointer;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __list_node(__link_pointer __prev, __link_pointer __next) : __base(__prev, __next) {}
+ _LIBCPP_HIDE_FROM_ABI ~__list_node() {}
+
+ _LIBCPP_HIDE_FROM_ABI __link_pointer __as_link() { return static_cast<__link_pointer>(__base::__self()); }
+};
+
+template <class _Tp, class _Alloc = allocator<_Tp> >
+class _LIBCPP_TEMPLATE_VIS list;
+template <class _Tp, class _Alloc>
+class __list_imp;
+template <class _Tp, class _VoidPtr>
+class _LIBCPP_TEMPLATE_VIS __list_const_iterator;
+
+template <class _Tp, class _VoidPtr>
+class _LIBCPP_TEMPLATE_VIS __list_iterator {
+ typedef __list_node_pointer_traits<_Tp, _VoidPtr> _NodeTraits;
+ typedef typename _NodeTraits::__link_pointer __link_pointer;
+
+ __link_pointer __ptr_;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __list_iterator(__link_pointer __p) _NOEXCEPT : __ptr_(__p) {}
+
+ template <class, class>
+ friend class list;
+ template <class, class>
+ friend class __list_imp;
+ template <class, class>
+ friend class __list_const_iterator;
+
+public:
+ typedef bidirectional_iterator_tag iterator_category;
+ typedef _Tp value_type;
+ typedef value_type& reference;
+ typedef __rebind_pointer_t<_VoidPtr, value_type> pointer;
+ typedef typename pointer_traits<pointer>::difference_type difference_type;
+
+ _LIBCPP_HIDE_FROM_ABI __list_iterator() _NOEXCEPT : __ptr_(nullptr) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __ptr_->__as_node()->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const {
+ return pointer_traits<pointer>::pointer_to(__ptr_->__as_node()->__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __list_iterator& operator++() {
+ __ptr_ = __ptr_->__next_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __list_iterator operator++(int) {
+ __list_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __list_iterator& operator--() {
+ __ptr_ = __ptr_->__prev_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __list_iterator operator--(int) {
+ __list_iterator __t(*this);
+ --(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __list_iterator& __x, const __list_iterator& __y) {
+ return __x.__ptr_ == __y.__ptr_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __list_iterator& __x, const __list_iterator& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _Tp, class _VoidPtr>
+class _LIBCPP_TEMPLATE_VIS __list_const_iterator {
+ typedef __list_node_pointer_traits<_Tp, _VoidPtr> _NodeTraits;
+ typedef typename _NodeTraits::__link_pointer __link_pointer;
+
+ __link_pointer __ptr_;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __list_const_iterator(__link_pointer __p) _NOEXCEPT : __ptr_(__p) {}
+
+ template <class, class>
+ friend class list;
+ template <class, class>
+ friend class __list_imp;
+
+public:
+ typedef bidirectional_iterator_tag iterator_category;
+ typedef _Tp value_type;
+ typedef const value_type& reference;
+ typedef __rebind_pointer_t<_VoidPtr, const value_type> pointer;
+ typedef typename pointer_traits<pointer>::difference_type difference_type;
+
+ _LIBCPP_HIDE_FROM_ABI __list_const_iterator() _NOEXCEPT : __ptr_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI __list_const_iterator(const __list_iterator<_Tp, _VoidPtr>& __p) _NOEXCEPT
+ : __ptr_(__p.__ptr_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __ptr_->__as_node()->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const {
+ return pointer_traits<pointer>::pointer_to(__ptr_->__as_node()->__get_value());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __list_const_iterator& operator++() {
+ __ptr_ = __ptr_->__next_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __list_const_iterator operator++(int) {
+ __list_const_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __list_const_iterator& operator--() {
+ __ptr_ = __ptr_->__prev_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __list_const_iterator operator--(int) {
+ __list_const_iterator __t(*this);
+ --(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __list_const_iterator& __x, const __list_const_iterator& __y) {
+ return __x.__ptr_ == __y.__ptr_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __list_const_iterator& __x, const __list_const_iterator& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _Tp, class _Alloc>
+class __list_imp {
+public:
+ __list_imp(const __list_imp&) = delete;
+ __list_imp& operator=(const __list_imp&) = delete;
+
+ typedef _Alloc allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+ typedef typename __alloc_traits::size_type size_type;
+
+protected:
+ typedef _Tp value_type;
+ typedef typename __alloc_traits::void_pointer __void_pointer;
+ typedef __list_iterator<value_type, __void_pointer> iterator;
+ typedef __list_const_iterator<value_type, __void_pointer> const_iterator;
+ typedef __list_node_base<value_type, __void_pointer> __node_base;
+ typedef __list_node<value_type, __void_pointer> __node_type;
+ typedef __rebind_alloc<__alloc_traits, __node_type> __node_allocator;
+ typedef allocator_traits<__node_allocator> __node_alloc_traits;
+ typedef typename __node_alloc_traits::pointer __node_pointer;
+ typedef typename __node_alloc_traits::pointer __node_const_pointer;
+ typedef __list_node_pointer_traits<value_type, __void_pointer> __node_pointer_traits;
+ typedef typename __node_pointer_traits::__link_pointer __link_pointer;
+ typedef __link_pointer __link_const_pointer;
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+ typedef typename __alloc_traits::difference_type difference_type;
+
+ typedef __rebind_alloc<__alloc_traits, __node_base> __node_base_allocator;
+ typedef typename allocator_traits<__node_base_allocator>::pointer __node_base_pointer;
+ static_assert(!is_same<allocator_type, __node_allocator>::value,
+ "internal allocator type must differ from user-specified type; otherwise overload resolution breaks");
+
+ __node_base __end_;
+ __compressed_pair<size_type, __node_allocator> __size_alloc_;
+
+ _LIBCPP_HIDE_FROM_ABI __link_pointer __end_as_link() const _NOEXCEPT {
+ return __node_pointer_traits::__unsafe_link_pointer_cast(const_cast<__node_base&>(__end_).__self());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type& __sz() _NOEXCEPT { return __size_alloc_.first(); }
+ _LIBCPP_HIDE_FROM_ABI const size_type& __sz() const _NOEXCEPT { return __size_alloc_.first(); }
+ _LIBCPP_HIDE_FROM_ABI __node_allocator& __node_alloc() _NOEXCEPT { return __size_alloc_.second(); }
+ _LIBCPP_HIDE_FROM_ABI const __node_allocator& __node_alloc() const _NOEXCEPT { return __size_alloc_.second(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type __node_alloc_max_size() const _NOEXCEPT {
+ return __node_alloc_traits::max_size(__node_alloc());
+ }
+ _LIBCPP_HIDE_FROM_ABI static void __unlink_nodes(__link_pointer __f, __link_pointer __l) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI __list_imp() _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value);
+ _LIBCPP_HIDE_FROM_ABI __list_imp(const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI __list_imp(const __node_allocator& __a);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __list_imp(__node_allocator&& __a) _NOEXCEPT;
+#endif
+ _LIBCPP_HIDE_FROM_ABI ~__list_imp();
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __sz() == 0; }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return iterator(__end_.__next_); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return const_iterator(__end_.__next_); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return iterator(__end_as_link()); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return const_iterator(__end_as_link()); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(__list_imp& __c)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT;
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>);
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __list_imp& __c) {
+ __copy_assign_alloc(
+ __c, integral_constant<bool, __node_alloc_traits::propagate_on_container_copy_assignment::value>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__list_imp& __c)
+ _NOEXCEPT_(!__node_alloc_traits::propagate_on_container_move_assignment::value ||
+ is_nothrow_move_assignable<__node_allocator>::value) {
+ __move_assign_alloc(
+ __c, integral_constant<bool, __node_alloc_traits::propagate_on_container_move_assignment::value>());
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI __node_pointer __create_node(__link_pointer __prev, __link_pointer __next, _Args&&... __args) {
+ __node_allocator& __alloc = __node_alloc();
+ __allocation_guard<__node_allocator> __guard(__alloc, 1);
+ // Begin the lifetime of the node itself. Note that this doesn't begin the lifetime of the value
+ // held inside the node, since we need to use the allocator's construct() method for that.
+ //
+ // We don't use the allocator's construct() method to construct the node itself since the
+ // Cpp17FooInsertable named requirements don't require the allocator's construct() method
+ // to work on anything other than the value_type.
+ std::__construct_at(std::addressof(*__guard.__get()), __prev, __next);
+
+ // Now construct the value_type using the allocator's construct() method.
+ __node_alloc_traits::construct(
+ __alloc, std::addressof(__guard.__get()->__get_value()), std::forward<_Args>(__args)...);
+ return __guard.__release_ptr();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __delete_node(__node_pointer __node) {
+ // For the same reason as above, we use the allocator's destroy() method for the value_type,
+ // but not for the node itself.
+ __node_allocator& __alloc = __node_alloc();
+ __node_alloc_traits::destroy(__alloc, std::addressof(__node->__get_value()));
+ std::__destroy_at(std::addressof(*__node));
+ __node_alloc_traits::deallocate(__alloc, __node, 1);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __list_imp& __c, true_type) {
+ if (__node_alloc() != __c.__node_alloc())
+ clear();
+ __node_alloc() = __c.__node_alloc();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const __list_imp&, false_type) {}
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__list_imp& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value) {
+ __node_alloc() = std::move(__c.__node_alloc());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__list_imp&, false_type) _NOEXCEPT {}
+};
+
+// Unlink nodes [__f, __l]
+template <class _Tp, class _Alloc>
+inline void __list_imp<_Tp, _Alloc>::__unlink_nodes(__link_pointer __f, __link_pointer __l) _NOEXCEPT {
+ __f->__prev_->__next_ = __l->__next_;
+ __l->__next_->__prev_ = __f->__prev_;
+}
+
+template <class _Tp, class _Alloc>
+inline __list_imp<_Tp, _Alloc>::__list_imp() _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value)
+ : __size_alloc_(0, __default_init_tag()) {}
+
+template <class _Tp, class _Alloc>
+inline __list_imp<_Tp, _Alloc>::__list_imp(const allocator_type& __a) : __size_alloc_(0, __node_allocator(__a)) {}
+
+template <class _Tp, class _Alloc>
+inline __list_imp<_Tp, _Alloc>::__list_imp(const __node_allocator& __a) : __size_alloc_(0, __a) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Tp, class _Alloc>
+inline __list_imp<_Tp, _Alloc>::__list_imp(__node_allocator&& __a) _NOEXCEPT : __size_alloc_(0, std::move(__a)) {}
+#endif
+
+template <class _Tp, class _Alloc>
+__list_imp<_Tp, _Alloc>::~__list_imp() {
+ clear();
+}
+
+template <class _Tp, class _Alloc>
+void __list_imp<_Tp, _Alloc>::clear() _NOEXCEPT {
+ if (!empty()) {
+ __link_pointer __f = __end_.__next_;
+ __link_pointer __l = __end_as_link();
+ __unlink_nodes(__f, __l->__prev_);
+ __sz() = 0;
+ while (__f != __l) {
+ __node_pointer __np = __f->__as_node();
+ __f = __f->__next_;
+ __delete_node(__np);
+ }
+ }
+}
+
+template <class _Tp, class _Alloc>
+void __list_imp<_Tp, _Alloc>::swap(__list_imp& __c)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>)
+#endif
+{
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __alloc_traits::propagate_on_container_swap::value || this->__node_alloc() == __c.__node_alloc(),
+ "list::swap: Either propagate_on_container_swap must be true"
+ " or the allocators must compare equal");
+ using std::swap;
+ std::__swap_allocator(__node_alloc(), __c.__node_alloc());
+ swap(__sz(), __c.__sz());
+ swap(__end_, __c.__end_);
+ if (__sz() == 0)
+ __end_.__next_ = __end_.__prev_ = __end_as_link();
+ else
+ __end_.__prev_->__next_ = __end_.__next_->__prev_ = __end_as_link();
+ if (__c.__sz() == 0)
+ __c.__end_.__next_ = __c.__end_.__prev_ = __c.__end_as_link();
+ else
+ __c.__end_.__prev_->__next_ = __c.__end_.__next_->__prev_ = __c.__end_as_link();
+}
+
+template <class _Tp, class _Alloc /*= allocator<_Tp>*/>
+class _LIBCPP_TEMPLATE_VIS list : private __list_imp<_Tp, _Alloc> {
+ typedef __list_imp<_Tp, _Alloc> base;
+ typedef typename base::__node_type __node_type;
+ typedef typename base::__node_allocator __node_allocator;
+ typedef typename base::__node_pointer __node_pointer;
+ typedef typename base::__node_alloc_traits __node_alloc_traits;
+ typedef typename base::__node_base __node_base;
+ typedef typename base::__node_base_pointer __node_base_pointer;
+ typedef typename base::__link_pointer __link_pointer;
+
+public:
+ typedef _Tp value_type;
+ typedef _Alloc allocator_type;
+ static_assert(__check_valid_allocator<allocator_type>::value);
+ static_assert(is_same<value_type, typename allocator_type::value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename base::pointer pointer;
+ typedef typename base::const_pointer const_pointer;
+ typedef typename base::size_type size_type;
+ typedef typename base::difference_type difference_type;
+ typedef typename base::iterator iterator;
+ typedef typename base::const_iterator const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+#if _LIBCPP_STD_VER >= 20
+ typedef size_type __remove_return_type;
+#else
+ typedef void __remove_return_type;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI list() _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value) {}
+ _LIBCPP_HIDE_FROM_ABI explicit list(const allocator_type& __a) : base(__a) {}
+ _LIBCPP_HIDE_FROM_ABI explicit list(size_type __n);
+#if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI explicit list(size_type __n, const allocator_type& __a);
+#endif
+ _LIBCPP_HIDE_FROM_ABI list(size_type __n, const value_type& __x);
+ template <__enable_if_t<__is_allocator<_Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI list(size_type __n, const value_type& __x, const allocator_type& __a) : base(__a) {
+ for (; __n > 0; --__n)
+ push_back(__x);
+ }
+
+ template <class _InpIter, __enable_if_t<__has_input_iterator_category<_InpIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI list(_InpIter __f, _InpIter __l);
+
+ template <class _InpIter, __enable_if_t<__has_input_iterator_category<_InpIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI list(_InpIter __f, _InpIter __l, const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI list(from_range_t, _Range&& __range, const allocator_type& __a = allocator_type()) : base(__a) {
+ prepend_range(std::forward<_Range>(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI list(const list& __c);
+ _LIBCPP_HIDE_FROM_ABI list(const list& __c, const __type_identity_t<allocator_type>& __a);
+ _LIBCPP_HIDE_FROM_ABI list& operator=(const list& __c);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI list(initializer_list<value_type> __il);
+ _LIBCPP_HIDE_FROM_ABI list(initializer_list<value_type> __il, const allocator_type& __a);
+
+ _LIBCPP_HIDE_FROM_ABI list(list&& __c) _NOEXCEPT_(is_nothrow_move_constructible<__node_allocator>::value);
+ _LIBCPP_HIDE_FROM_ABI list(list&& __c, const __type_identity_t<allocator_type>& __a);
+ _LIBCPP_HIDE_FROM_ABI list& operator=(list&& __c)
+ _NOEXCEPT_(__node_alloc_traits::propagate_on_container_move_assignment::value&&
+ is_nothrow_move_assignable<__node_allocator>::value);
+
+ _LIBCPP_HIDE_FROM_ABI list& operator=(initializer_list<value_type> __il) {
+ assign(__il.begin(), __il.end());
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void assign(initializer_list<value_type> __il) { assign(__il.begin(), __il.end()); }
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class _InpIter, __enable_if_t<__has_input_iterator_category<_InpIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI void assign(_InpIter __f, _InpIter __l);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void assign_range(_Range&& __range) {
+ __assign_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void assign(size_type __n, const value_type& __x);
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return base::__sz(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return base::empty(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT {
+ return std::min<size_type>(base::__node_alloc_max_size(), numeric_limits<difference_type >::max());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return base::begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return base::begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return base::end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return base::end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return base::begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return base::end(); }
+
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() _NOEXCEPT { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const _NOEXCEPT { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() _NOEXCEPT { return reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const _NOEXCEPT { return const_reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const _NOEXCEPT { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const _NOEXCEPT { return const_reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI reference front() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "list::front called on empty list");
+ return base::__end_.__next_->__as_node()->__get_value();
+ }
+ _LIBCPP_HIDE_FROM_ABI const_reference front() const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "list::front called on empty list");
+ return base::__end_.__next_->__as_node()->__get_value();
+ }
+ _LIBCPP_HIDE_FROM_ABI reference back() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "list::back called on empty list");
+ return base::__end_.__prev_->__as_node()->__get_value();
+ }
+ _LIBCPP_HIDE_FROM_ABI const_reference back() const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "list::back called on empty list");
+ return base::__end_.__prev_->__as_node()->__get_value();
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void push_front(value_type&& __x);
+ _LIBCPP_HIDE_FROM_ABI void push_back(value_type&& __x);
+
+# if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void prepend_range(_Range&& __range) {
+ insert_range(begin(), std::forward<_Range>(__range));
+ }
+
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void append_range(_Range&& __range) {
+ insert_range(end(), std::forward<_Range>(__range));
+ }
+# endif
+
+ template <class... _Args>
+# if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI reference emplace_front(_Args&&... __args);
+# else
+ _LIBCPP_HIDE_FROM_ABI void emplace_front(_Args&&... __args);
+# endif
+ template <class... _Args>
+# if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI reference emplace_back(_Args&&... __args);
+# else
+ _LIBCPP_HIDE_FROM_ABI void emplace_back(_Args&&... __args);
+# endif
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace(const_iterator __p, _Args&&... __args);
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __x);
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, initializer_list<value_type> __il) {
+ return insert(__p, __il.begin(), __il.end());
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI void push_front(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI void push_back(const value_type& __x);
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Arg>
+ _LIBCPP_HIDE_FROM_ABI void __emplace_back(_Arg&& __arg) {
+ emplace_back(std::forward<_Arg>(__arg));
+ }
+#else
+ _LIBCPP_HIDE_FROM_ABI void __emplace_back(value_type const& __arg) { push_back(__arg); }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, size_type __n, const value_type& __x);
+
+ template <class _InpIter, __enable_if_t<__has_input_iterator_category<_InpIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, _InpIter __f, _InpIter __l);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_range(const_iterator __position, _Range&& __range) {
+ return __insert_with_sentinel(__position, ranges::begin(__range), ranges::end(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void swap(list& __c)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(!__node_alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>)
+#endif
+ {
+ base::swap(__c);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { base::clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI void pop_front();
+ _LIBCPP_HIDE_FROM_ABI void pop_back();
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p);
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __f, const_iterator __l);
+
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n);
+ _LIBCPP_HIDE_FROM_ABI void resize(size_type __n, const value_type& __x);
+
+ _LIBCPP_HIDE_FROM_ABI void splice(const_iterator __p, list& __c);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void splice(const_iterator __p, list&& __c) { splice(__p, __c); }
+ _LIBCPP_HIDE_FROM_ABI void splice(const_iterator __p, list&& __c, const_iterator __i) { splice(__p, __c, __i); }
+ _LIBCPP_HIDE_FROM_ABI void splice(const_iterator __p, list&& __c, const_iterator __f, const_iterator __l) {
+ splice(__p, __c, __f, __l);
+ }
+#endif
+ _LIBCPP_HIDE_FROM_ABI void splice(const_iterator __p, list& __c, const_iterator __i);
+ _LIBCPP_HIDE_FROM_ABI void splice(const_iterator __p, list& __c, const_iterator __f, const_iterator __l);
+
+ _LIBCPP_HIDE_FROM_ABI __remove_return_type remove(const value_type& __x);
+ template <class _Pred>
+ _LIBCPP_HIDE_FROM_ABI __remove_return_type remove_if(_Pred __pred);
+ _LIBCPP_HIDE_FROM_ABI __remove_return_type unique() { return unique(__equal_to()); }
+ template <class _BinaryPred>
+ _LIBCPP_HIDE_FROM_ABI __remove_return_type unique(_BinaryPred __binary_pred);
+ _LIBCPP_HIDE_FROM_ABI void merge(list& __c);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void merge(list&& __c) { merge(__c); }
+
+ template <class _Comp>
+ _LIBCPP_HIDE_FROM_ABI void merge(list&& __c, _Comp __comp) {
+ merge(__c, __comp);
+ }
+#endif
+ template <class _Comp>
+ _LIBCPP_HIDE_FROM_ABI void merge(list& __c, _Comp __comp);
+
+ _LIBCPP_HIDE_FROM_ABI void sort();
+ template <class _Comp>
+ _LIBCPP_HIDE_FROM_ABI void sort(_Comp __comp);
+
+ _LIBCPP_HIDE_FROM_ABI void reverse() _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI bool __invariants() const;
+
+private:
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI void __assign_with_sentinel(_Iterator __f, _Sentinel __l);
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI iterator __insert_with_sentinel(const_iterator __p, _Iterator __f, _Sentinel __l);
+
+ _LIBCPP_HIDE_FROM_ABI static void __link_nodes(__link_pointer __p, __link_pointer __f, __link_pointer __l);
+ _LIBCPP_HIDE_FROM_ABI void __link_nodes_at_front(__link_pointer __f, __link_pointer __l);
+ _LIBCPP_HIDE_FROM_ABI void __link_nodes_at_back(__link_pointer __f, __link_pointer __l);
+ _LIBCPP_HIDE_FROM_ABI iterator __iterator(size_type __n);
+ // TODO: Make this _LIBCPP_HIDE_FROM_ABI
+ template <class _Comp>
+ _LIBCPP_HIDDEN static iterator __sort(iterator __f1, iterator __e2, size_type __n, _Comp& __comp);
+
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(list& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value);
+ _LIBCPP_HIDE_FROM_ABI void __move_assign(list& __c, false_type);
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Alloc = allocator<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+list(_InputIterator, _InputIterator) -> list<__iter_value_type<_InputIterator>, _Alloc>;
+
+template <class _InputIterator,
+ class _Alloc,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+list(_InputIterator, _InputIterator, _Alloc) -> list<__iter_value_type<_InputIterator>, _Alloc>;
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Alloc = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+list(from_range_t, _Range&&, _Alloc = _Alloc()) -> list<ranges::range_value_t<_Range>, _Alloc>;
+#endif
+
+// Link in nodes [__f, __l] just prior to __p
+template <class _Tp, class _Alloc>
+inline void list<_Tp, _Alloc>::__link_nodes(__link_pointer __p, __link_pointer __f, __link_pointer __l) {
+ __p->__prev_->__next_ = __f;
+ __f->__prev_ = __p->__prev_;
+ __p->__prev_ = __l;
+ __l->__next_ = __p;
+}
+
+// Link in nodes [__f, __l] at the front of the list
+template <class _Tp, class _Alloc>
+inline void list<_Tp, _Alloc>::__link_nodes_at_front(__link_pointer __f, __link_pointer __l) {
+ __f->__prev_ = base::__end_as_link();
+ __l->__next_ = base::__end_.__next_;
+ __l->__next_->__prev_ = __l;
+ base::__end_.__next_ = __f;
+}
+
+// Link in nodes [__f, __l] at the back of the list
+template <class _Tp, class _Alloc>
+inline void list<_Tp, _Alloc>::__link_nodes_at_back(__link_pointer __f, __link_pointer __l) {
+ __l->__next_ = base::__end_as_link();
+ __f->__prev_ = base::__end_.__prev_;
+ __f->__prev_->__next_ = __f;
+ base::__end_.__prev_ = __l;
+}
+
+template <class _Tp, class _Alloc>
+inline typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::__iterator(size_type __n) {
+ return __n <= base::__sz() / 2 ? std::next(begin(), __n) : std::prev(end(), base::__sz() - __n);
+}
+
+template <class _Tp, class _Alloc>
+list<_Tp, _Alloc>::list(size_type __n) {
+ for (; __n > 0; --__n)
+#ifndef _LIBCPP_CXX03_LANG
+ emplace_back();
+#else
+ push_back(value_type());
+#endif
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Tp, class _Alloc>
+list<_Tp, _Alloc>::list(size_type __n, const allocator_type& __a) : base(__a) {
+ for (; __n > 0; --__n)
+ emplace_back();
+}
+#endif
+
+template <class _Tp, class _Alloc>
+list<_Tp, _Alloc>::list(size_type __n, const value_type& __x) {
+ for (; __n > 0; --__n)
+ push_back(__x);
+}
+
+template <class _Tp, class _Alloc>
+template <class _InpIter, __enable_if_t<__has_input_iterator_category<_InpIter>::value, int> >
+list<_Tp, _Alloc>::list(_InpIter __f, _InpIter __l) {
+ for (; __f != __l; ++__f)
+ __emplace_back(*__f);
+}
+
+template <class _Tp, class _Alloc>
+template <class _InpIter, __enable_if_t<__has_input_iterator_category<_InpIter>::value, int> >
+list<_Tp, _Alloc>::list(_InpIter __f, _InpIter __l, const allocator_type& __a) : base(__a) {
+ for (; __f != __l; ++__f)
+ __emplace_back(*__f);
+}
+
+template <class _Tp, class _Alloc>
+list<_Tp, _Alloc>::list(const list& __c)
+ : base(__node_alloc_traits::select_on_container_copy_construction(__c.__node_alloc())) {
+ for (const_iterator __i = __c.begin(), __e = __c.end(); __i != __e; ++__i)
+ push_back(*__i);
+}
+
+template <class _Tp, class _Alloc>
+list<_Tp, _Alloc>::list(const list& __c, const __type_identity_t<allocator_type>& __a) : base(__a) {
+ for (const_iterator __i = __c.begin(), __e = __c.end(); __i != __e; ++__i)
+ push_back(*__i);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+list<_Tp, _Alloc>::list(initializer_list<value_type> __il, const allocator_type& __a) : base(__a) {
+ for (typename initializer_list<value_type>::const_iterator __i = __il.begin(), __e = __il.end(); __i != __e; ++__i)
+ push_back(*__i);
+}
+
+template <class _Tp, class _Alloc>
+list<_Tp, _Alloc>::list(initializer_list<value_type> __il) {
+ for (typename initializer_list<value_type>::const_iterator __i = __il.begin(), __e = __il.end(); __i != __e; ++__i)
+ push_back(*__i);
+}
+
+template <class _Tp, class _Alloc>
+inline list<_Tp, _Alloc>::list(list&& __c) noexcept(is_nothrow_move_constructible<__node_allocator>::value)
+ : base(std::move(__c.__node_alloc())) {
+ splice(end(), __c);
+}
+
+template <class _Tp, class _Alloc>
+inline list<_Tp, _Alloc>::list(list&& __c, const __type_identity_t<allocator_type>& __a) : base(__a) {
+ if (__a == __c.get_allocator())
+ splice(end(), __c);
+ else {
+ typedef move_iterator<iterator> _Ip;
+ assign(_Ip(__c.begin()), _Ip(__c.end()));
+ }
+}
+
+template <class _Tp, class _Alloc>
+inline list<_Tp, _Alloc>& list<_Tp, _Alloc>::operator=(list&& __c) noexcept(
+ __node_alloc_traits::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<__node_allocator>::value) {
+ __move_assign(__c, integral_constant<bool, __node_alloc_traits::propagate_on_container_move_assignment::value>());
+ return *this;
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::__move_assign(list& __c, false_type) {
+ if (base::__node_alloc() != __c.__node_alloc()) {
+ typedef move_iterator<iterator> _Ip;
+ assign(_Ip(__c.begin()), _Ip(__c.end()));
+ } else
+ __move_assign(__c, true_type());
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::__move_assign(list& __c,
+ true_type) noexcept(is_nothrow_move_assignable<__node_allocator>::value) {
+ clear();
+ base::__move_assign_alloc(__c);
+ splice(end(), __c);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+inline list<_Tp, _Alloc>& list<_Tp, _Alloc>::operator=(const list& __c) {
+ if (this != std::addressof(__c)) {
+ base::__copy_assign_alloc(__c);
+ assign(__c.begin(), __c.end());
+ }
+ return *this;
+}
+
+template <class _Tp, class _Alloc>
+template <class _InpIter, __enable_if_t<__has_input_iterator_category<_InpIter>::value, int> >
+void list<_Tp, _Alloc>::assign(_InpIter __f, _InpIter __l) {
+ __assign_with_sentinel(__f, __l);
+}
+
+template <class _Tp, class _Alloc>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI void list<_Tp, _Alloc>::__assign_with_sentinel(_Iterator __f, _Sentinel __l) {
+ iterator __i = begin();
+ iterator __e = end();
+ for (; __f != __l && __i != __e; ++__f, (void)++__i)
+ *__i = *__f;
+ if (__i == __e)
+ __insert_with_sentinel(__e, std::move(__f), std::move(__l));
+ else
+ erase(__i, __e);
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::assign(size_type __n, const value_type& __x) {
+ iterator __i = begin();
+ iterator __e = end();
+ for (; __n > 0 && __i != __e; --__n, (void)++__i)
+ *__i = __x;
+ if (__i == __e)
+ insert(__e, __n, __x);
+ else
+ erase(__i, __e);
+}
+
+template <class _Tp, class _Alloc>
+inline _Alloc list<_Tp, _Alloc>::get_allocator() const _NOEXCEPT {
+ return allocator_type(base::__node_alloc());
+}
+
+template <class _Tp, class _Alloc>
+typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::insert(const_iterator __p, const value_type& __x) {
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, __x);
+ __link_nodes(__p.__ptr_, __node->__as_link(), __node->__as_link());
+ ++base::__sz();
+ return iterator(__node->__as_link());
+}
+
+template <class _Tp, class _Alloc>
+typename list<_Tp, _Alloc>::iterator
+list<_Tp, _Alloc>::insert(const_iterator __p, size_type __n, const value_type& __x) {
+ iterator __r(__p.__ptr_);
+ if (__n > 0) {
+ size_type __ds = 0;
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, __x);
+ ++__ds;
+ __r = iterator(__node->__as_link());
+ iterator __e = __r;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (--__n; __n != 0; --__n, (void)++__e, ++__ds) {
+ __e.__ptr_->__next_ = this->__create_node(/* prev = */ __e.__ptr_, /* next = */ nullptr, __x)->__as_link();
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ while (true) {
+ __link_pointer __prev = __e.__ptr_->__prev_;
+ __node_pointer __current = __e.__ptr_->__as_node();
+ this->__delete_node(__current);
+ if (__prev == 0)
+ break;
+ __e = iterator(__prev);
+ }
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __link_nodes(__p.__ptr_, __r.__ptr_, __e.__ptr_);
+ base::__sz() += __ds;
+ }
+ return __r;
+}
+
+template <class _Tp, class _Alloc>
+template <class _InpIter, __enable_if_t<__has_input_iterator_category<_InpIter>::value, int> >
+typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::insert(const_iterator __p, _InpIter __f, _InpIter __l) {
+ return __insert_with_sentinel(__p, __f, __l);
+}
+
+template <class _Tp, class _Alloc>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI typename list<_Tp, _Alloc>::iterator
+list<_Tp, _Alloc>::__insert_with_sentinel(const_iterator __p, _Iterator __f, _Sentinel __l) {
+ iterator __r(__p.__ptr_);
+ if (__f != __l) {
+ size_type __ds = 0;
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, *__f);
+ ++__ds;
+ __r = iterator(__node->__as_link());
+ iterator __e = __r;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (++__f; __f != __l; ++__f, (void)++__e, ++__ds) {
+ __e.__ptr_->__next_ = this->__create_node(/* prev = */ __e.__ptr_, /* next = */ nullptr, *__f)->__as_link();
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ while (true) {
+ __link_pointer __prev = __e.__ptr_->__prev_;
+ __node_pointer __current = __e.__ptr_->__as_node();
+ this->__delete_node(__current);
+ if (__prev == 0)
+ break;
+ __e = iterator(__prev);
+ }
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __link_nodes(__p.__ptr_, __r.__ptr_, __e.__ptr_);
+ base::__sz() += __ds;
+ }
+ return __r;
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::push_front(const value_type& __x) {
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, __x);
+ __link_pointer __nl = __node->__as_link();
+ __link_nodes_at_front(__nl, __nl);
+ ++base::__sz();
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::push_back(const value_type& __x) {
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, __x);
+ __link_pointer __nl = __node->__as_link();
+ __link_nodes_at_back(__nl, __nl);
+ ++base::__sz();
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::push_front(value_type&& __x) {
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::move(__x));
+ __link_pointer __nl = __node->__as_link();
+ __link_nodes_at_front(__nl, __nl);
+ ++base::__sz();
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::push_back(value_type&& __x) {
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::move(__x));
+ __link_pointer __nl = __node->__as_link();
+ __link_nodes_at_back(__nl, __nl);
+ ++base::__sz();
+}
+
+template <class _Tp, class _Alloc>
+template <class... _Args>
+# if _LIBCPP_STD_VER >= 17
+typename list<_Tp, _Alloc>::reference
+# else
+void
+# endif
+list<_Tp, _Alloc>::emplace_front(_Args&&... __args) {
+ __node_pointer __node =
+ this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::forward<_Args>(__args)...);
+ __link_pointer __nl = __node->__as_link();
+ __link_nodes_at_front(__nl, __nl);
+ ++base::__sz();
+# if _LIBCPP_STD_VER >= 17
+ return __node->__get_value();
+# endif
+}
+
+template <class _Tp, class _Alloc>
+template <class... _Args>
+# if _LIBCPP_STD_VER >= 17
+typename list<_Tp, _Alloc>::reference
+# else
+void
+# endif
+list<_Tp, _Alloc>::emplace_back(_Args&&... __args) {
+ __node_pointer __node =
+ this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::forward<_Args>(__args)...);
+ __link_pointer __nl = __node->__as_link();
+ __link_nodes_at_back(__nl, __nl);
+ ++base::__sz();
+# if _LIBCPP_STD_VER >= 17
+ return __node->__get_value();
+# endif
+}
+
+template <class _Tp, class _Alloc>
+template <class... _Args>
+typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::emplace(const_iterator __p, _Args&&... __args) {
+ __node_pointer __node =
+ this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::forward<_Args>(__args)...);
+ __link_pointer __nl = __node->__as_link();
+ __link_nodes(__p.__ptr_, __nl, __nl);
+ ++base::__sz();
+ return iterator(__nl);
+}
+
+template <class _Tp, class _Alloc>
+typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::insert(const_iterator __p, value_type&& __x) {
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::move(__x));
+ __link_pointer __nl = __node->__as_link();
+ __link_nodes(__p.__ptr_, __nl, __nl);
+ ++base::__sz();
+ return iterator(__nl);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::pop_front() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "list::pop_front() called with empty list");
+ __link_pointer __n = base::__end_.__next_;
+ base::__unlink_nodes(__n, __n);
+ --base::__sz();
+ this->__delete_node(__n->__as_node());
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::pop_back() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "list::pop_back() called on an empty list");
+ __link_pointer __n = base::__end_.__prev_;
+ base::__unlink_nodes(__n, __n);
+ --base::__sz();
+ this->__delete_node(__n->__as_node());
+}
+
+template <class _Tp, class _Alloc>
+typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::erase(const_iterator __p) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__p != end(), "list::erase(iterator) called with a non-dereferenceable iterator");
+ __link_pointer __n = __p.__ptr_;
+ __link_pointer __r = __n->__next_;
+ base::__unlink_nodes(__n, __n);
+ --base::__sz();
+ this->__delete_node(__n->__as_node());
+ return iterator(__r);
+}
+
+template <class _Tp, class _Alloc>
+typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::erase(const_iterator __f, const_iterator __l) {
+ if (__f != __l) {
+ base::__unlink_nodes(__f.__ptr_, __l.__ptr_->__prev_);
+ while (__f != __l) {
+ __link_pointer __n = __f.__ptr_;
+ ++__f;
+ --base::__sz();
+ this->__delete_node(__n->__as_node());
+ }
+ }
+ return iterator(__l.__ptr_);
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::resize(size_type __n) {
+ if (__n < base::__sz())
+ erase(__iterator(__n), end());
+ else if (__n > base::__sz()) {
+ __n -= base::__sz();
+ size_type __ds = 0;
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr);
+ ++__ds;
+ iterator __r = iterator(__node->__as_link());
+ iterator __e = __r;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (--__n; __n != 0; --__n, (void)++__e, ++__ds) {
+ __e.__ptr_->__next_ = this->__create_node(/* prev = */ __e.__ptr_, /* next = */ nullptr)->__as_link();
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ while (true) {
+ __link_pointer __prev = __e.__ptr_->__prev_;
+ __node_pointer __current = __e.__ptr_->__as_node();
+ this->__delete_node(__current);
+ if (__prev == 0)
+ break;
+ __e = iterator(__prev);
+ }
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __link_nodes_at_back(__r.__ptr_, __e.__ptr_);
+ base::__sz() += __ds;
+ }
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::resize(size_type __n, const value_type& __x) {
+ if (__n < base::__sz())
+ erase(__iterator(__n), end());
+ else if (__n > base::__sz()) {
+ __n -= base::__sz();
+ size_type __ds = 0;
+ __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, __x);
+ ++__ds;
+ __link_pointer __nl = __node->__as_link();
+ iterator __r = iterator(__nl);
+ iterator __e = __r;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (--__n; __n != 0; --__n, (void)++__e, ++__ds) {
+ __e.__ptr_->__next_ = this->__create_node(/* prev = */ __e.__ptr_, /* next = */ nullptr, __x)->__as_link();
+ }
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ while (true) {
+ __link_pointer __prev = __e.__ptr_->__prev_;
+ __node_pointer __current = __e.__ptr_->__as_node();
+ this->__delete_node(__current);
+ if (__prev == 0)
+ break;
+ __e = iterator(__prev);
+ }
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __link_nodes(base::__end_as_link(), __r.__ptr_, __e.__ptr_);
+ base::__sz() += __ds;
+ }
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::splice(const_iterator __p, list& __c) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(
+ this != std::addressof(__c), "list::splice(iterator, list) called with this == &list");
+ if (!__c.empty()) {
+ __link_pointer __f = __c.__end_.__next_;
+ __link_pointer __l = __c.__end_.__prev_;
+ base::__unlink_nodes(__f, __l);
+ __link_nodes(__p.__ptr_, __f, __l);
+ base::__sz() += __c.__sz();
+ __c.__sz() = 0;
+ }
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __i) {
+ if (__p.__ptr_ != __i.__ptr_ && __p.__ptr_ != __i.__ptr_->__next_) {
+ __link_pointer __f = __i.__ptr_;
+ base::__unlink_nodes(__f, __f);
+ __link_nodes(__p.__ptr_, __f, __f);
+ --__c.__sz();
+ ++base::__sz();
+ }
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __f, const_iterator __l) {
+ if (__f != __l) {
+ __link_pointer __first = __f.__ptr_;
+ --__l;
+ __link_pointer __last = __l.__ptr_;
+ if (this != std::addressof(__c)) {
+ size_type __s = std::distance(__f, __l) + 1;
+ __c.__sz() -= __s;
+ base::__sz() += __s;
+ }
+ base::__unlink_nodes(__first, __last);
+ __link_nodes(__p.__ptr_, __first, __last);
+ }
+}
+
+template <class _Tp, class _Alloc>
+typename list<_Tp, _Alloc>::__remove_return_type list<_Tp, _Alloc>::remove(const value_type& __x) {
+ list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
+ for (const_iterator __i = begin(), __e = end(); __i != __e;) {
+ if (*__i == __x) {
+ const_iterator __j = std::next(__i);
+ for (; __j != __e && *__j == __x; ++__j)
+ ;
+ __deleted_nodes.splice(__deleted_nodes.end(), *this, __i, __j);
+ __i = __j;
+ if (__i != __e)
+ ++__i;
+ } else
+ ++__i;
+ }
+
+ return (__remove_return_type)__deleted_nodes.size();
+}
+
+template <class _Tp, class _Alloc>
+template <class _Pred>
+typename list<_Tp, _Alloc>::__remove_return_type list<_Tp, _Alloc>::remove_if(_Pred __pred) {
+ list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
+ for (iterator __i = begin(), __e = end(); __i != __e;) {
+ if (__pred(*__i)) {
+ iterator __j = std::next(__i);
+ for (; __j != __e && __pred(*__j); ++__j)
+ ;
+ __deleted_nodes.splice(__deleted_nodes.end(), *this, __i, __j);
+ __i = __j;
+ if (__i != __e)
+ ++__i;
+ } else
+ ++__i;
+ }
+
+ return (__remove_return_type)__deleted_nodes.size();
+}
+
+template <class _Tp, class _Alloc>
+template <class _BinaryPred>
+typename list<_Tp, _Alloc>::__remove_return_type list<_Tp, _Alloc>::unique(_BinaryPred __binary_pred) {
+ list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
+ for (iterator __i = begin(), __e = end(); __i != __e;) {
+ iterator __j = std::next(__i);
+ for (; __j != __e && __binary_pred(*__i, *__j); ++__j)
+ ;
+ if (++__i != __j) {
+ __deleted_nodes.splice(__deleted_nodes.end(), *this, __i, __j);
+ __i = __j;
+ }
+ }
+
+ return (__remove_return_type)__deleted_nodes.size();
+}
+
+template <class _Tp, class _Alloc>
+inline void list<_Tp, _Alloc>::merge(list& __c) {
+ merge(__c, __less<>());
+}
+
+template <class _Tp, class _Alloc>
+template <class _Comp>
+void list<_Tp, _Alloc>::merge(list& __c, _Comp __comp) {
+ if (this != std::addressof(__c)) {
+ iterator __f1 = begin();
+ iterator __e1 = end();
+ iterator __f2 = __c.begin();
+ iterator __e2 = __c.end();
+ while (__f1 != __e1 && __f2 != __e2) {
+ if (__comp(*__f2, *__f1)) {
+ size_type __ds = 1;
+ iterator __m2 = std::next(__f2);
+ for (; __m2 != __e2 && __comp(*__m2, *__f1); ++__m2, (void)++__ds)
+ ;
+ base::__sz() += __ds;
+ __c.__sz() -= __ds;
+ __link_pointer __f = __f2.__ptr_;
+ __link_pointer __l = __m2.__ptr_->__prev_;
+ __f2 = __m2;
+ base::__unlink_nodes(__f, __l);
+ __m2 = std::next(__f1);
+ __link_nodes(__f1.__ptr_, __f, __l);
+ __f1 = __m2;
+ } else
+ ++__f1;
+ }
+ splice(__e1, __c);
+ }
+}
+
+template <class _Tp, class _Alloc>
+inline void list<_Tp, _Alloc>::sort() {
+ sort(__less<>());
+}
+
+template <class _Tp, class _Alloc>
+template <class _Comp>
+inline void list<_Tp, _Alloc>::sort(_Comp __comp) {
+ __sort(begin(), end(), base::__sz(), __comp);
+}
+
+template <class _Tp, class _Alloc>
+template <class _Comp>
+typename list<_Tp, _Alloc>::iterator
+list<_Tp, _Alloc>::__sort(iterator __f1, iterator __e2, size_type __n, _Comp& __comp) {
+ switch (__n) {
+ case 0:
+ case 1:
+ return __f1;
+ case 2:
+ if (__comp(*--__e2, *__f1)) {
+ __link_pointer __f = __e2.__ptr_;
+ base::__unlink_nodes(__f, __f);
+ __link_nodes(__f1.__ptr_, __f, __f);
+ return __e2;
+ }
+ return __f1;
+ }
+ size_type __n2 = __n / 2;
+ iterator __e1 = std::next(__f1, __n2);
+ iterator __r = __f1 = __sort(__f1, __e1, __n2, __comp);
+ iterator __f2 = __e1 = __sort(__e1, __e2, __n - __n2, __comp);
+ if (__comp(*__f2, *__f1)) {
+ iterator __m2 = std::next(__f2);
+ for (; __m2 != __e2 && __comp(*__m2, *__f1); ++__m2)
+ ;
+ __link_pointer __f = __f2.__ptr_;
+ __link_pointer __l = __m2.__ptr_->__prev_;
+ __r = __f2;
+ __e1 = __f2 = __m2;
+ base::__unlink_nodes(__f, __l);
+ __m2 = std::next(__f1);
+ __link_nodes(__f1.__ptr_, __f, __l);
+ __f1 = __m2;
+ } else
+ ++__f1;
+ while (__f1 != __e1 && __f2 != __e2) {
+ if (__comp(*__f2, *__f1)) {
+ iterator __m2 = std::next(__f2);
+ for (; __m2 != __e2 && __comp(*__m2, *__f1); ++__m2)
+ ;
+ __link_pointer __f = __f2.__ptr_;
+ __link_pointer __l = __m2.__ptr_->__prev_;
+ if (__e1 == __f2)
+ __e1 = __m2;
+ __f2 = __m2;
+ base::__unlink_nodes(__f, __l);
+ __m2 = std::next(__f1);
+ __link_nodes(__f1.__ptr_, __f, __l);
+ __f1 = __m2;
+ } else
+ ++__f1;
+ }
+ return __r;
+}
+
+template <class _Tp, class _Alloc>
+void list<_Tp, _Alloc>::reverse() _NOEXCEPT {
+ if (base::__sz() > 1) {
+ iterator __e = end();
+ for (iterator __i = begin(); __i.__ptr_ != __e.__ptr_;) {
+ std::swap(__i.__ptr_->__prev_, __i.__ptr_->__next_);
+ __i.__ptr_ = __i.__ptr_->__prev_;
+ }
+ std::swap(__e.__ptr_->__prev_, __e.__ptr_->__next_);
+ }
+}
+
+template <class _Tp, class _Alloc>
+bool list<_Tp, _Alloc>::__invariants() const {
+ return size() == std::distance(begin(), end());
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y) {
+ return __x.size() == __y.size() && std::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y) {
+ return __y < __x;
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y) {
+ return !(__y < __x);
+}
+
+#else // _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __synth_three_way_result<_Tp>
+operator<=>(const list<_Tp, _Allocator>& __x, const list<_Tp, _Allocator>& __y) {
+ return std::lexicographical_compare_three_way(
+ __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void swap(list<_Tp, _Alloc>& __x, list<_Tp, _Alloc>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Allocator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename list<_Tp, _Allocator>::size_type
+erase_if(list<_Tp, _Allocator>& __c, _Predicate __pred) {
+ return __c.remove_if(__pred);
+}
+
+template <class _Tp, class _Allocator, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI typename list<_Tp, _Allocator>::size_type
+erase(list<_Tp, _Allocator>& __c, const _Up& __v) {
+ return std::erase_if(__c, [&](auto& __elem) { return __elem == __v; });
+}
+
+template <>
+inline constexpr bool __format::__enable_insertable<std::list<char>> = true;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+inline constexpr bool __format::__enable_insertable<std::list<wchar_t>> = true;
+# endif
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _ValueT>
+using list _LIBCPP_AVAILABILITY_PMR = std::list<_ValueT, polymorphic_allocator<_ValueT>>;
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <atomic>
+# include <concepts>
+# include <cstdint>
+# include <cstdlib>
+# include <functional>
+# include <iosfwd>
+# include <iterator>
+# include <stdexcept>
+# include <type_traits>
+# include <typeinfo>
+#endif
+
+#endif // _LIBCPP_LIST
diff --git a/libcxx/include/__cxx03/locale b/libcxx/include/__cxx03/locale
new file mode 100644
index 00000000000000..573910a85bef54
--- /dev/null
+++ b/libcxx/include/__cxx03/locale
@@ -0,0 +1,3767 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_LOCALE
+#define _LIBCPP_LOCALE
+
+/*
+ locale synopsis
+
+namespace std
+{
+
+class locale
+{
+public:
+ // types:
+ class facet;
+ class id;
+
+ typedef int category;
+ static const category // values assigned here are for exposition only
+ none = 0x000,
+ collate = 0x010,
+ ctype = 0x020,
+ monetary = 0x040,
+ numeric = 0x080,
+ time = 0x100,
+ messages = 0x200,
+ all = collate | ctype | monetary | numeric | time | messages;
+
+ // construct/copy/destroy:
+ locale() noexcept;
+ locale(const locale& other) noexcept;
+ explicit locale(const char* std_name);
+ explicit locale(const string& std_name);
+ locale(const locale& other, const char* std_name, category);
+ locale(const locale& other, const string& std_name, category);
+ template <class Facet> locale(const locale& other, Facet* f);
+ locale(const locale& other, const locale& one, category);
+
+ ~locale(); // not virtual
+
+ const locale& operator=(const locale& other) noexcept;
+
+ template <class Facet> locale combine(const locale& other) const;
+
+ // locale operations:
+ basic_string<char> name() const;
+ bool operator==(const locale& other) const;
+ bool operator!=(const locale& other) const; // removed C++20
+ template <class charT, class Traits, class Allocator>
+ bool operator()(const basic_string<charT,Traits,Allocator>& s1,
+ const basic_string<charT,Traits,Allocator>& s2) const;
+
+ // global locale objects:
+ static locale global(const locale&);
+ static const locale& classic();
+};
+
+template <class Facet> const Facet& use_facet(const locale&);
+template <class Facet> bool has_facet(const locale&) noexcept;
+
+// 22.3.3, convenience interfaces:
+template <class charT> bool isspace (charT c, const locale& loc);
+template <class charT> bool isprint (charT c, const locale& loc);
+template <class charT> bool iscntrl (charT c, const locale& loc);
+template <class charT> bool isupper (charT c, const locale& loc);
+template <class charT> bool islower (charT c, const locale& loc);
+template <class charT> bool isalpha (charT c, const locale& loc);
+template <class charT> bool isdigit (charT c, const locale& loc);
+template <class charT> bool ispunct (charT c, const locale& loc);
+template <class charT> bool isxdigit(charT c, const locale& loc);
+template <class charT> bool isalnum (charT c, const locale& loc);
+template <class charT> bool isgraph (charT c, const locale& loc);
+template <class charT> charT toupper(charT c, const locale& loc);
+template <class charT> charT tolower(charT c, const locale& loc);
+
+template<class Codecvt, class Elem = wchar_t,
+ class Wide_alloc = allocator<Elem>,
+ class Byte_alloc = allocator<char>>
+class wstring_convert // Removed in C++26
+{
+public:
+ typedef basic_string<char, char_traits<char>, Byte_alloc> byte_string;
+ typedef basic_string<Elem, char_traits<Elem>, Wide_alloc> wide_string;
+ typedef typename Codecvt::state_type state_type;
+ typedef typename wide_string::traits_type::int_type int_type;
+
+ wstring_convert(Codecvt* pcvt = new Codecvt); // before C++14
+ explicit wstring_convert(Codecvt* pcvt = new Codecvt); // before C++20
+ wstring_convert() : wstring_convert(new Codecvt) {} // C++20
+ explicit wstring_convert(Codecvt* pcvt); // C++20
+
+ wstring_convert(Codecvt* pcvt, state_type state);
+ explicit wstring_convert(const byte_string& byte_err, // explicit in C++14
+ const wide_string& wide_err = wide_string());
+ wstring_convert(const wstring_convert&) = delete; // C++14
+ wstring_convert & operator=(const wstring_convert &) = delete; // C++14
+ ~wstring_convert();
+
+ wide_string from_bytes(char byte);
+ wide_string from_bytes(const char* ptr);
+ wide_string from_bytes(const byte_string& str);
+ wide_string from_bytes(const char* first, const char* last);
+
+ byte_string to_bytes(Elem wchar);
+ byte_string to_bytes(const Elem* wptr);
+ byte_string to_bytes(const wide_string& wstr);
+ byte_string to_bytes(const Elem* first, const Elem* last);
+
+ size_t converted() const; // noexcept in C++14
+ state_type state() const;
+};
+
+template <class Codecvt, class Elem = wchar_t, class Tr = char_traits<Elem>>
+class wbuffer_convert // Removed in C++26
+ : public basic_streambuf<Elem, Tr>
+{
+public:
+ typedef typename Tr::state_type state_type;
+
+ wbuffer_convert(streambuf* bytebuf = 0, Codecvt* pcvt = new Codecvt,
+ state_type state = state_type()); // before C++14
+ explicit wbuffer_convert(streambuf* bytebuf = nullptr, Codecvt* pcvt = new Codecvt,
+ state_type state = state_type()); // before C++20
+ wbuffer_convert() : wbuffer_convert(nullptr) {} // C++20
+ explicit wbuffer_convert(streambuf* bytebuf, Codecvt* pcvt = new Codecvt,
+ state_type state = state_type()); // C++20
+
+ wbuffer_convert(const wbuffer_convert&) = delete; // C++14
+ wbuffer_convert & operator=(const wbuffer_convert &) = delete; // C++14
+ ~wbuffer_convert(); // C++14
+
+ streambuf* rdbuf() const;
+ streambuf* rdbuf(streambuf* bytebuf);
+
+ state_type state() const;
+};
+
+// 22.4.1 and 22.4.1.3, ctype:
+class ctype_base;
+template <class charT> class ctype;
+template <> class ctype<char>; // specialization
+template <class charT> class ctype_byname;
+template <> class ctype_byname<char>; // specialization
+
+class codecvt_base;
+template <class internT, class externT, class stateT> class codecvt;
+template <class internT, class externT, class stateT> class codecvt_byname;
+
+// 22.4.2 and 22.4.3, numeric:
+template <class charT, class InputIterator> class num_get;
+template <class charT, class OutputIterator> class num_put;
+template <class charT> class numpunct;
+template <class charT> class numpunct_byname;
+
+// 22.4.4, col lation:
+template <class charT> class collate;
+template <class charT> class collate_byname;
+
+// 22.4.5, date and time:
+class time_base;
+template <class charT, class InputIterator> class time_get;
+template <class charT, class InputIterator> class time_get_byname;
+template <class charT, class OutputIterator> class time_put;
+template <class charT, class OutputIterator> class time_put_byname;
+
+// 22.4.6, money:
+class money_base;
+template <class charT, class InputIterator> class money_get;
+template <class charT, class OutputIterator> class money_put;
+template <class charT, bool Intl> class moneypunct;
+template <class charT, bool Intl> class moneypunct_byname;
+
+// 22.4.7, message retrieval:
+class messages_base;
+template <class charT> class messages;
+template <class charT> class messages_byname;
+
+} // std
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+# include <__algorithm/copy.h>
+# include <__algorithm/equal.h>
+# include <__algorithm/find.h>
+# include <__algorithm/max.h>
+# include <__algorithm/reverse.h>
+# include <__algorithm/unwrap_iter.h>
+# include <__assert>
+# include <__iterator/access.h>
+# include <__iterator/back_insert_iterator.h>
+# include <__iterator/istreambuf_iterator.h>
+# include <__iterator/ostreambuf_iterator.h>
+# include <__locale>
+# include <__memory/unique_ptr.h>
+# include <__type_traits/make_unsigned.h>
+# include <cerrno>
+# include <cstdio>
+# include <cstdlib>
+# include <ctime>
+# include <ios>
+# include <limits>
+# include <new>
+# include <streambuf>
+# include <version>
+
+// TODO: Fix __bsd_locale_defaults.h
+// NOLINTBEGIN(libcpp-robust-against-adl)
+
+# if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
+// Most unix variants have catopen. These are the specific ones that don't.
+# if !defined(__BIONIC__) && !defined(_NEWLIB_VERSION) && !defined(__EMSCRIPTEN__)
+# define _LIBCPP_HAS_CATOPEN 1
+# include <nl_types.h>
+# endif
+# endif
+
+# ifdef _LIBCPP_LOCALE__L_EXTENSIONS
+# include <__locale_dir/locale_base_api/bsd_locale_defaults.h>
+# else
+# include <__locale_dir/locale_base_api/bsd_locale_fallbacks.h>
+# endif
+
+# if defined(__APPLE__) || defined(__FreeBSD__)
+# include <xlocale.h>
+# endif
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if defined(__APPLE__) || defined(__FreeBSD__)
+# define _LIBCPP_GET_C_LOCALE 0
+# elif defined(__NetBSD__)
+# define _LIBCPP_GET_C_LOCALE LC_C_LOCALE
+# else
+# define _LIBCPP_GET_C_LOCALE __cloc()
+// Get the C locale object
+_LIBCPP_EXPORTED_FROM_ABI locale_t __cloc();
+# define __cloc_defined
+# endif
+
+// __scan_keyword
+// Scans [__b, __e) until a match is found in the basic_strings range
+// [__kb, __ke) or until it can be shown that there is no match in [__kb, __ke).
+// __b will be incremented (visibly), consuming CharT until a match is found
+// or proved to not exist. A keyword may be "", in which will match anything.
+// If one keyword is a prefix of another, and the next CharT in the input
+// might match another keyword, the algorithm will attempt to find the longest
+// matching keyword. If the longer matching keyword ends up not matching, then
+// no keyword match is found. If no keyword match is found, __ke is returned
+// and failbit is set in __err.
+// Else an iterator pointing to the matching keyword is found. If more than
+// one keyword matches, an iterator to the first matching keyword is returned.
+// If on exit __b == __e, eofbit is set in __err. If __case_sensitive is false,
+// __ct is used to force to lower case before comparing characters.
+// Examples:
+// Keywords: "a", "abb"
+// If the input is "a", the first keyword matches and eofbit is set.
+// If the input is "abc", no match is found and "ab" are consumed.
+template <class _InputIterator, class _ForwardIterator, class _Ctype>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator __scan_keyword(
+ _InputIterator& __b,
+ _InputIterator __e,
+ _ForwardIterator __kb,
+ _ForwardIterator __ke,
+ const _Ctype& __ct,
+ ios_base::iostate& __err,
+ bool __case_sensitive = true) {
+ typedef typename iterator_traits<_InputIterator>::value_type _CharT;
+ size_t __nkw = static_cast<size_t>(std::distance(__kb, __ke));
+ const unsigned char __doesnt_match = '\0';
+ const unsigned char __might_match = '\1';
+ const unsigned char __does_match = '\2';
+ unsigned char __statbuf[100];
+ unsigned char* __status = __statbuf;
+ unique_ptr<unsigned char, void (*)(void*)> __stat_hold(nullptr, free);
+ if (__nkw > sizeof(__statbuf)) {
+ __status = (unsigned char*)malloc(__nkw);
+ if (__status == nullptr)
+ __throw_bad_alloc();
+ __stat_hold.reset(__status);
+ }
+ size_t __n_might_match = __nkw; // At this point, any keyword might match
+ size_t __n_does_match = 0; // but none of them definitely do
+ // Initialize all statuses to __might_match, except for "" keywords are __does_match
+ unsigned char* __st = __status;
+ for (_ForwardIterator __ky = __kb; __ky != __ke; ++__ky, (void)++__st) {
+ if (!__ky->empty())
+ *__st = __might_match;
+ else {
+ *__st = __does_match;
+ --__n_might_match;
+ ++__n_does_match;
+ }
+ }
+ // While there might be a match, test keywords against the next CharT
+ for (size_t __indx = 0; __b != __e && __n_might_match > 0; ++__indx) {
+ // Peek at the next CharT but don't consume it
+ _CharT __c = *__b;
+ if (!__case_sensitive)
+ __c = __ct.toupper(__c);
+ bool __consume = false;
+ // For each keyword which might match, see if the __indx character is __c
+ // If a match if found, consume __c
+ // If a match is found, and that is the last character in the keyword,
+ // then that keyword matches.
+ // If the keyword doesn't match this character, then change the keyword
+ // to doesn't match
+ __st = __status;
+ for (_ForwardIterator __ky = __kb; __ky != __ke; ++__ky, (void)++__st) {
+ if (*__st == __might_match) {
+ _CharT __kc = (*__ky)[__indx];
+ if (!__case_sensitive)
+ __kc = __ct.toupper(__kc);
+ if (__c == __kc) {
+ __consume = true;
+ if (__ky->size() == __indx + 1) {
+ *__st = __does_match;
+ --__n_might_match;
+ ++__n_does_match;
+ }
+ } else {
+ *__st = __doesnt_match;
+ --__n_might_match;
+ }
+ }
+ }
+ // consume if we matched a character
+ if (__consume) {
+ ++__b;
+ // If we consumed a character and there might be a matched keyword that
+ // was marked matched on a previous iteration, then such keywords
+ // which are now marked as not matching.
+ if (__n_might_match + __n_does_match > 1) {
+ __st = __status;
+ for (_ForwardIterator __ky = __kb; __ky != __ke; ++__ky, (void)++__st) {
+ if (*__st == __does_match && __ky->size() != __indx + 1) {
+ *__st = __doesnt_match;
+ --__n_does_match;
+ }
+ }
+ }
+ }
+ }
+ // We've exited the loop because we hit eof and/or we have no more "might matches".
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ // Return the first matching result
+ for (__st = __status; __kb != __ke; ++__kb, (void)++__st)
+ if (*__st == __does_match)
+ break;
+ if (__kb == __ke)
+ __err |= ios_base::failbit;
+ return __kb;
+}
+
+struct _LIBCPP_EXPORTED_FROM_ABI __num_get_base {
+ static const int __num_get_buf_sz = 40;
+
+ static int __get_base(ios_base&);
+ static const char __src[33]; // "0123456789abcdefABCDEFxX+-pPiInN"
+ // count of leading characters in __src used for parsing integers ("012..X+-")
+ static const size_t __int_chr_cnt = 26;
+ // count of leading characters in __src used for parsing floating-point values ("012..-pP")
+ static const size_t __fp_chr_cnt = 28;
+};
+
+_LIBCPP_EXPORTED_FROM_ABI void
+__check_grouping(const string& __grouping, unsigned* __g, unsigned* __g_end, ios_base::iostate& __err);
+
+template <class _CharT>
+struct __num_get : protected __num_get_base {
+ static string __stage2_float_prep(ios_base& __iob, _CharT* __atoms, _CharT& __decimal_point, _CharT& __thousands_sep);
+
+ static int __stage2_float_loop(
+ _CharT __ct,
+ bool& __in_units,
+ char& __exp,
+ char* __a,
+ char*& __a_end,
+ _CharT __decimal_point,
+ _CharT __thousands_sep,
+ const string& __grouping,
+ unsigned* __g,
+ unsigned*& __g_end,
+ unsigned& __dc,
+ _CharT* __atoms);
+# ifndef _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
+ static string __stage2_int_prep(ios_base& __iob, _CharT* __atoms, _CharT& __thousands_sep);
+ static int __stage2_int_loop(
+ _CharT __ct,
+ int __base,
+ char* __a,
+ char*& __a_end,
+ unsigned& __dc,
+ _CharT __thousands_sep,
+ const string& __grouping,
+ unsigned* __g,
+ unsigned*& __g_end,
+ _CharT* __atoms);
+
+# else
+ static string __stage2_int_prep(ios_base& __iob, _CharT& __thousands_sep) {
+ locale __loc = __iob.getloc();
+ const numpunct<_CharT>& __np = use_facet<numpunct<_CharT> >(__loc);
+ __thousands_sep = __np.thousands_sep();
+ return __np.grouping();
+ }
+
+ const _CharT* __do_widen(ios_base& __iob, _CharT* __atoms) const { return __do_widen_p(__iob, __atoms); }
+
+ static int __stage2_int_loop(
+ _CharT __ct,
+ int __base,
+ char* __a,
+ char*& __a_end,
+ unsigned& __dc,
+ _CharT __thousands_sep,
+ const string& __grouping,
+ unsigned* __g,
+ unsigned*& __g_end,
+ const _CharT* __atoms);
+
+private:
+ template <typename _Tp>
+ const _Tp* __do_widen_p(ios_base& __iob, _Tp* __atoms) const {
+ locale __loc = __iob.getloc();
+ use_facet<ctype<_Tp> >(__loc).widen(__src, __src + __int_chr_cnt, __atoms);
+ return __atoms;
+ }
+
+ const char* __do_widen_p(ios_base& __iob, char* __atoms) const {
+ (void)__iob;
+ (void)__atoms;
+ return __src;
+ }
+# endif
+};
+
+# ifndef _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
+template <class _CharT>
+string __num_get<_CharT>::__stage2_int_prep(ios_base& __iob, _CharT* __atoms, _CharT& __thousands_sep) {
+ locale __loc = __iob.getloc();
+ std::use_facet<ctype<_CharT> >(__loc).widen(__src, __src + __int_chr_cnt, __atoms);
+ const numpunct<_CharT>& __np = std::use_facet<numpunct<_CharT> >(__loc);
+ __thousands_sep = __np.thousands_sep();
+ return __np.grouping();
+}
+# endif
+
+template <class _CharT>
+string __num_get<_CharT>::__stage2_float_prep(
+ ios_base& __iob, _CharT* __atoms, _CharT& __decimal_point, _CharT& __thousands_sep) {
+ locale __loc = __iob.getloc();
+ std::use_facet<ctype<_CharT> >(__loc).widen(__src, __src + __fp_chr_cnt, __atoms);
+ const numpunct<_CharT>& __np = std::use_facet<numpunct<_CharT> >(__loc);
+ __decimal_point = __np.decimal_point();
+ __thousands_sep = __np.thousands_sep();
+ return __np.grouping();
+}
+
+template <class _CharT>
+int
+# ifndef _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
+__num_get<_CharT>::__stage2_int_loop(_CharT __ct, int __base, char* __a, char*& __a_end,
+ unsigned& __dc, _CharT __thousands_sep, const string& __grouping,
+ unsigned* __g, unsigned*& __g_end, _CharT* __atoms)
+# else
+__num_get<_CharT>::__stage2_int_loop(_CharT __ct, int __base, char* __a, char*& __a_end,
+ unsigned& __dc, _CharT __thousands_sep, const string& __grouping,
+ unsigned* __g, unsigned*& __g_end, const _CharT* __atoms)
+
+# endif
+{
+ if (__a_end == __a && (__ct == __atoms[24] || __ct == __atoms[25])) {
+ *__a_end++ = __ct == __atoms[24] ? '+' : '-';
+ __dc = 0;
+ return 0;
+ }
+ if (__grouping.size() != 0 && __ct == __thousands_sep) {
+ if (__g_end - __g < __num_get_buf_sz) {
+ *__g_end++ = __dc;
+ __dc = 0;
+ }
+ return 0;
+ }
+ ptrdiff_t __f = std::find(__atoms, __atoms + __int_chr_cnt, __ct) - __atoms;
+ if (__f >= 24)
+ return -1;
+ switch (__base) {
+ case 8:
+ case 10:
+ if (__f >= __base)
+ return -1;
+ break;
+ case 16:
+ if (__f < 22)
+ break;
+ if (__a_end != __a && __a_end - __a <= 2 && __a_end[-1] == '0') {
+ __dc = 0;
+ *__a_end++ = __src[__f];
+ return 0;
+ }
+ return -1;
+ }
+ *__a_end++ = __src[__f];
+ ++__dc;
+ return 0;
+}
+
+template <class _CharT>
+int __num_get<_CharT>::__stage2_float_loop(
+ _CharT __ct,
+ bool& __in_units,
+ char& __exp,
+ char* __a,
+ char*& __a_end,
+ _CharT __decimal_point,
+ _CharT __thousands_sep,
+ const string& __grouping,
+ unsigned* __g,
+ unsigned*& __g_end,
+ unsigned& __dc,
+ _CharT* __atoms) {
+ if (__ct == __decimal_point) {
+ if (!__in_units)
+ return -1;
+ __in_units = false;
+ *__a_end++ = '.';
+ if (__grouping.size() != 0 && __g_end - __g < __num_get_buf_sz)
+ *__g_end++ = __dc;
+ return 0;
+ }
+ if (__ct == __thousands_sep && __grouping.size() != 0) {
+ if (!__in_units)
+ return -1;
+ if (__g_end - __g < __num_get_buf_sz) {
+ *__g_end++ = __dc;
+ __dc = 0;
+ }
+ return 0;
+ }
+ ptrdiff_t __f = std::find(__atoms, __atoms + __num_get_base::__fp_chr_cnt, __ct) - __atoms;
+ if (__f >= static_cast<ptrdiff_t>(__num_get_base::__fp_chr_cnt))
+ return -1;
+ char __x = __src[__f];
+ if (__x == '-' || __x == '+') {
+ if (__a_end == __a || (std::toupper(__a_end[-1]) == std::toupper(__exp))) {
+ *__a_end++ = __x;
+ return 0;
+ }
+ return -1;
+ }
+ if (__x == 'x' || __x == 'X')
+ __exp = 'P';
+ else if (std::toupper(__x) == __exp) {
+ __exp = std::tolower(__exp);
+ if (__in_units) {
+ __in_units = false;
+ if (__grouping.size() != 0 && __g_end - __g < __num_get_buf_sz)
+ *__g_end++ = __dc;
+ }
+ }
+ *__a_end++ = __x;
+ if (__f >= 22)
+ return 0;
+ ++__dc;
+ return 0;
+}
+
+extern template struct _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __num_get<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template struct _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __num_get<wchar_t>;
+# endif
+
+template <class _CharT, class _InputIterator = istreambuf_iterator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS num_get : public locale::facet, private __num_get<_CharT> {
+public:
+ typedef _CharT char_type;
+ typedef _InputIterator iter_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit num_get(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, bool& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, long& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, long long& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, unsigned short& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, unsigned int& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, unsigned long& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, unsigned long long& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, float& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, double& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, long double& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, void*& __v) const {
+ return do_get(__b, __e, __iob, __err, __v);
+ }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~num_get() override {}
+
+ template <class _Fp>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS iter_type
+ __do_get_floating_point(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, _Fp& __v) const;
+
+ template <class _Signed>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS iter_type
+ __do_get_signed(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, _Signed& __v) const;
+
+ template <class _Unsigned>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS iter_type
+ __do_get_unsigned(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, _Unsigned& __v) const;
+
+ virtual iter_type do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, bool& __v) const;
+
+ virtual iter_type do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, long& __v) const {
+ return this->__do_get_signed(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type
+ do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, long long& __v) const {
+ return this->__do_get_signed(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type
+ do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, unsigned short& __v) const {
+ return this->__do_get_unsigned(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type
+ do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, unsigned int& __v) const {
+ return this->__do_get_unsigned(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type
+ do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, unsigned long& __v) const {
+ return this->__do_get_unsigned(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type
+ do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, unsigned long long& __v) const {
+ return this->__do_get_unsigned(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, float& __v) const {
+ return this->__do_get_floating_point(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, double& __v) const {
+ return this->__do_get_floating_point(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type
+ do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, long double& __v) const {
+ return this->__do_get_floating_point(__b, __e, __iob, __err, __v);
+ }
+
+ virtual iter_type do_get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, void*& __v) const;
+};
+
+template <class _CharT, class _InputIterator>
+locale::id num_get<_CharT, _InputIterator>::id;
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__num_get_signed_integral(const char* __a, const char* __a_end, ios_base::iostate& __err, int __base) {
+ if (__a != __a_end) {
+ __libcpp_remove_reference_t<decltype(errno)> __save_errno = errno;
+ errno = 0;
+ char* __p2;
+ long long __ll = strtoll_l(__a, &__p2, __base, _LIBCPP_GET_C_LOCALE);
+ __libcpp_remove_reference_t<decltype(errno)> __current_errno = errno;
+ if (__current_errno == 0)
+ errno = __save_errno;
+ if (__p2 != __a_end) {
+ __err = ios_base::failbit;
+ return 0;
+ } else if (__current_errno == ERANGE || __ll < numeric_limits<_Tp>::min() || numeric_limits<_Tp>::max() < __ll) {
+ __err = ios_base::failbit;
+ if (__ll > 0)
+ return numeric_limits<_Tp>::max();
+ else
+ return numeric_limits<_Tp>::min();
+ }
+ return static_cast<_Tp>(__ll);
+ }
+ __err = ios_base::failbit;
+ return 0;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp
+__num_get_unsigned_integral(const char* __a, const char* __a_end, ios_base::iostate& __err, int __base) {
+ if (__a != __a_end) {
+ const bool __negate = *__a == '-';
+ if (__negate && ++__a == __a_end) {
+ __err = ios_base::failbit;
+ return 0;
+ }
+ __libcpp_remove_reference_t<decltype(errno)> __save_errno = errno;
+ errno = 0;
+ char* __p2;
+ unsigned long long __ll = strtoull_l(__a, &__p2, __base, _LIBCPP_GET_C_LOCALE);
+ __libcpp_remove_reference_t<decltype(errno)> __current_errno = errno;
+ if (__current_errno == 0)
+ errno = __save_errno;
+ if (__p2 != __a_end) {
+ __err = ios_base::failbit;
+ return 0;
+ } else if (__current_errno == ERANGE || numeric_limits<_Tp>::max() < __ll) {
+ __err = ios_base::failbit;
+ return numeric_limits<_Tp>::max();
+ }
+ _Tp __res = static_cast<_Tp>(__ll);
+ if (__negate)
+ __res = -__res;
+ return __res;
+ }
+ __err = ios_base::failbit;
+ return 0;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp __do_strtod(const char* __a, char** __p2);
+
+template <>
+inline _LIBCPP_HIDE_FROM_ABI float __do_strtod<float>(const char* __a, char** __p2) {
+ return strtof_l(__a, __p2, _LIBCPP_GET_C_LOCALE);
+}
+
+template <>
+inline _LIBCPP_HIDE_FROM_ABI double __do_strtod<double>(const char* __a, char** __p2) {
+ return strtod_l(__a, __p2, _LIBCPP_GET_C_LOCALE);
+}
+
+template <>
+inline _LIBCPP_HIDE_FROM_ABI long double __do_strtod<long double>(const char* __a, char** __p2) {
+ return strtold_l(__a, __p2, _LIBCPP_GET_C_LOCALE);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp __num_get_float(const char* __a, const char* __a_end, ios_base::iostate& __err) {
+ if (__a != __a_end) {
+ __libcpp_remove_reference_t<decltype(errno)> __save_errno = errno;
+ errno = 0;
+ char* __p2;
+ _Tp __ld = std::__do_strtod<_Tp>(__a, &__p2);
+ __libcpp_remove_reference_t<decltype(errno)> __current_errno = errno;
+ if (__current_errno == 0)
+ errno = __save_errno;
+ if (__p2 != __a_end) {
+ __err = ios_base::failbit;
+ return 0;
+ } else if (__current_errno == ERANGE)
+ __err = ios_base::failbit;
+ return __ld;
+ }
+ __err = ios_base::failbit;
+ return 0;
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator num_get<_CharT, _InputIterator>::do_get(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, bool& __v) const {
+ if ((__iob.flags() & ios_base::boolalpha) == 0) {
+ long __lv = -1;
+ __b = do_get(__b, __e, __iob, __err, __lv);
+ switch (__lv) {
+ case 0:
+ __v = false;
+ break;
+ case 1:
+ __v = true;
+ break;
+ default:
+ __v = true;
+ __err = ios_base::failbit;
+ break;
+ }
+ return __b;
+ }
+ const ctype<_CharT>& __ct = std::use_facet<ctype<_CharT> >(__iob.getloc());
+ const numpunct<_CharT>& __np = std::use_facet<numpunct<_CharT> >(__iob.getloc());
+ typedef typename numpunct<_CharT>::string_type string_type;
+ const string_type __names[2] = {__np.truename(), __np.falsename()};
+ const string_type* __i = std::__scan_keyword(__b, __e, __names, __names + 2, __ct, __err);
+ __v = __i == __names;
+ return __b;
+}
+
+// signed
+
+template <class _CharT, class _InputIterator>
+template <class _Signed>
+_InputIterator num_get<_CharT, _InputIterator>::__do_get_signed(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, _Signed& __v) const {
+ // Stage 1
+ int __base = this->__get_base(__iob);
+ // Stage 2
+ char_type __thousands_sep;
+ const int __atoms_size = __num_get_base::__int_chr_cnt;
+# ifdef _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
+ char_type __atoms1[__atoms_size];
+ const char_type* __atoms = this->__do_widen(__iob, __atoms1);
+ string __grouping = this->__stage2_int_prep(__iob, __thousands_sep);
+# else
+ char_type __atoms[__atoms_size];
+ string __grouping = this->__stage2_int_prep(__iob, __atoms, __thousands_sep);
+# endif
+ string __buf;
+ __buf.resize(__buf.capacity());
+ char* __a = &__buf[0];
+ char* __a_end = __a;
+ unsigned __g[__num_get_base::__num_get_buf_sz];
+ unsigned* __g_end = __g;
+ unsigned __dc = 0;
+ for (; __b != __e; ++__b) {
+ if (__a_end == __a + __buf.size()) {
+ size_t __tmp = __buf.size();
+ __buf.resize(2 * __buf.size());
+ __buf.resize(__buf.capacity());
+ __a = &__buf[0];
+ __a_end = __a + __tmp;
+ }
+ if (this->__stage2_int_loop(*__b, __base, __a, __a_end, __dc, __thousands_sep, __grouping, __g, __g_end, __atoms))
+ break;
+ }
+ if (__grouping.size() != 0 && __g_end - __g < __num_get_base::__num_get_buf_sz)
+ *__g_end++ = __dc;
+ // Stage 3
+ __v = std::__num_get_signed_integral<_Signed>(__a, __a_end, __err, __base);
+ // Digit grouping checked
+ __check_grouping(__grouping, __g, __g_end, __err);
+ // EOF checked
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ return __b;
+}
+
+// unsigned
+
+template <class _CharT, class _InputIterator>
+template <class _Unsigned>
+_InputIterator num_get<_CharT, _InputIterator>::__do_get_unsigned(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, _Unsigned& __v) const {
+ // Stage 1
+ int __base = this->__get_base(__iob);
+ // Stage 2
+ char_type __thousands_sep;
+ const int __atoms_size = __num_get_base::__int_chr_cnt;
+# ifdef _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
+ char_type __atoms1[__atoms_size];
+ const char_type* __atoms = this->__do_widen(__iob, __atoms1);
+ string __grouping = this->__stage2_int_prep(__iob, __thousands_sep);
+# else
+ char_type __atoms[__atoms_size];
+ string __grouping = this->__stage2_int_prep(__iob, __atoms, __thousands_sep);
+# endif
+ string __buf;
+ __buf.resize(__buf.capacity());
+ char* __a = &__buf[0];
+ char* __a_end = __a;
+ unsigned __g[__num_get_base::__num_get_buf_sz];
+ unsigned* __g_end = __g;
+ unsigned __dc = 0;
+ for (; __b != __e; ++__b) {
+ if (__a_end == __a + __buf.size()) {
+ size_t __tmp = __buf.size();
+ __buf.resize(2 * __buf.size());
+ __buf.resize(__buf.capacity());
+ __a = &__buf[0];
+ __a_end = __a + __tmp;
+ }
+ if (this->__stage2_int_loop(*__b, __base, __a, __a_end, __dc, __thousands_sep, __grouping, __g, __g_end, __atoms))
+ break;
+ }
+ if (__grouping.size() != 0 && __g_end - __g < __num_get_base::__num_get_buf_sz)
+ *__g_end++ = __dc;
+ // Stage 3
+ __v = std::__num_get_unsigned_integral<_Unsigned>(__a, __a_end, __err, __base);
+ // Digit grouping checked
+ __check_grouping(__grouping, __g, __g_end, __err);
+ // EOF checked
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ return __b;
+}
+
+// floating point
+
+template <class _CharT, class _InputIterator>
+template <class _Fp>
+_InputIterator num_get<_CharT, _InputIterator>::__do_get_floating_point(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, _Fp& __v) const {
+ // Stage 1, nothing to do
+ // Stage 2
+ char_type __atoms[__num_get_base::__fp_chr_cnt];
+ char_type __decimal_point;
+ char_type __thousands_sep;
+ string __grouping = this->__stage2_float_prep(__iob, __atoms, __decimal_point, __thousands_sep);
+ string __buf;
+ __buf.resize(__buf.capacity());
+ char* __a = &__buf[0];
+ char* __a_end = __a;
+ unsigned __g[__num_get_base::__num_get_buf_sz];
+ unsigned* __g_end = __g;
+ unsigned __dc = 0;
+ bool __in_units = true;
+ char __exp = 'E';
+ bool __is_leading_parsed = false;
+ for (; __b != __e; ++__b) {
+ if (__a_end == __a + __buf.size()) {
+ size_t __tmp = __buf.size();
+ __buf.resize(2 * __buf.size());
+ __buf.resize(__buf.capacity());
+ __a = &__buf[0];
+ __a_end = __a + __tmp;
+ }
+ if (this->__stage2_float_loop(
+ *__b,
+ __in_units,
+ __exp,
+ __a,
+ __a_end,
+ __decimal_point,
+ __thousands_sep,
+ __grouping,
+ __g,
+ __g_end,
+ __dc,
+ __atoms))
+ break;
+
+ // the leading character excluding the sign must be a decimal digit
+ if (!__is_leading_parsed) {
+ if (__a_end - __a >= 1 && __a[0] != '-' && __a[0] != '+') {
+ if (('0' <= __a[0] && __a[0] <= '9') || __a[0] == '.')
+ __is_leading_parsed = true;
+ else
+ break;
+ } else if (__a_end - __a >= 2 && (__a[0] == '-' || __a[0] == '+')) {
+ if (('0' <= __a[1] && __a[1] <= '9') || __a[1] == '.')
+ __is_leading_parsed = true;
+ else
+ break;
+ }
+ }
+ }
+ if (__grouping.size() != 0 && __in_units && __g_end - __g < __num_get_base::__num_get_buf_sz)
+ *__g_end++ = __dc;
+ // Stage 3
+ __v = std::__num_get_float<_Fp>(__a, __a_end, __err);
+ // Digit grouping checked
+ __check_grouping(__grouping, __g, __g_end, __err);
+ // EOF checked
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ return __b;
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator num_get<_CharT, _InputIterator>::do_get(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, void*& __v) const {
+ // Stage 1
+ int __base = 16;
+ // Stage 2
+ char_type __atoms[__num_get_base::__int_chr_cnt];
+ char_type __thousands_sep = char_type();
+ string __grouping;
+ std::use_facet<ctype<_CharT> >(__iob.getloc())
+ .widen(__num_get_base::__src, __num_get_base::__src + __num_get_base::__int_chr_cnt, __atoms);
+ string __buf;
+ __buf.resize(__buf.capacity());
+ char* __a = &__buf[0];
+ char* __a_end = __a;
+ unsigned __g[__num_get_base::__num_get_buf_sz];
+ unsigned* __g_end = __g;
+ unsigned __dc = 0;
+ for (; __b != __e; ++__b) {
+ if (__a_end == __a + __buf.size()) {
+ size_t __tmp = __buf.size();
+ __buf.resize(2 * __buf.size());
+ __buf.resize(__buf.capacity());
+ __a = &__buf[0];
+ __a_end = __a + __tmp;
+ }
+ if (this->__stage2_int_loop(*__b, __base, __a, __a_end, __dc, __thousands_sep, __grouping, __g, __g_end, __atoms))
+ break;
+ }
+ // Stage 3
+ __buf.resize(__a_end - __a);
+ if (__libcpp_sscanf_l(__buf.c_str(), _LIBCPP_GET_C_LOCALE, "%p", &__v) != 1)
+ __err = ios_base::failbit;
+ // EOF checked
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ return __b;
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS num_get<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS num_get<wchar_t>;
+# endif
+
+struct _LIBCPP_EXPORTED_FROM_ABI __num_put_base {
+protected:
+ static void __format_int(char* __fmt, const char* __len, bool __signd, ios_base::fmtflags __flags);
+ static bool __format_float(char* __fmt, const char* __len, ios_base::fmtflags __flags);
+ static char* __identify_padding(char* __nb, char* __ne, const ios_base& __iob);
+};
+
+template <class _CharT>
+struct __num_put : protected __num_put_base {
+ static void __widen_and_group_int(
+ char* __nb, char* __np, char* __ne, _CharT* __ob, _CharT*& __op, _CharT*& __oe, const locale& __loc);
+ static void __widen_and_group_float(
+ char* __nb, char* __np, char* __ne, _CharT* __ob, _CharT*& __op, _CharT*& __oe, const locale& __loc);
+};
+
+template <class _CharT>
+void __num_put<_CharT>::__widen_and_group_int(
+ char* __nb, char* __np, char* __ne, _CharT* __ob, _CharT*& __op, _CharT*& __oe, const locale& __loc) {
+ const ctype<_CharT>& __ct = std::use_facet<ctype<_CharT> >(__loc);
+ const numpunct<_CharT>& __npt = std::use_facet<numpunct<_CharT> >(__loc);
+ string __grouping = __npt.grouping();
+ if (__grouping.empty()) {
+ __ct.widen(__nb, __ne, __ob);
+ __oe = __ob + (__ne - __nb);
+ } else {
+ __oe = __ob;
+ char* __nf = __nb;
+ if (*__nf == '-' || *__nf == '+')
+ *__oe++ = __ct.widen(*__nf++);
+ if (__ne - __nf >= 2 && __nf[0] == '0' && (__nf[1] == 'x' || __nf[1] == 'X')) {
+ *__oe++ = __ct.widen(*__nf++);
+ *__oe++ = __ct.widen(*__nf++);
+ }
+ std::reverse(__nf, __ne);
+ _CharT __thousands_sep = __npt.thousands_sep();
+ unsigned __dc = 0;
+ unsigned __dg = 0;
+ for (char* __p = __nf; __p < __ne; ++__p) {
+ if (static_cast<unsigned>(__grouping[__dg]) > 0 && __dc == static_cast<unsigned>(__grouping[__dg])) {
+ *__oe++ = __thousands_sep;
+ __dc = 0;
+ if (__dg < __grouping.size() - 1)
+ ++__dg;
+ }
+ *__oe++ = __ct.widen(*__p);
+ ++__dc;
+ }
+ std::reverse(__ob + (__nf - __nb), __oe);
+ }
+ if (__np == __ne)
+ __op = __oe;
+ else
+ __op = __ob + (__np - __nb);
+}
+
+template <class _CharT>
+void __num_put<_CharT>::__widen_and_group_float(
+ char* __nb, char* __np, char* __ne, _CharT* __ob, _CharT*& __op, _CharT*& __oe, const locale& __loc) {
+ const ctype<_CharT>& __ct = std::use_facet<ctype<_CharT> >(__loc);
+ const numpunct<_CharT>& __npt = std::use_facet<numpunct<_CharT> >(__loc);
+ string __grouping = __npt.grouping();
+ __oe = __ob;
+ char* __nf = __nb;
+ if (*__nf == '-' || *__nf == '+')
+ *__oe++ = __ct.widen(*__nf++);
+ char* __ns;
+ if (__ne - __nf >= 2 && __nf[0] == '0' && (__nf[1] == 'x' || __nf[1] == 'X')) {
+ *__oe++ = __ct.widen(*__nf++);
+ *__oe++ = __ct.widen(*__nf++);
+ for (__ns = __nf; __ns < __ne; ++__ns)
+ if (!isxdigit_l(*__ns, _LIBCPP_GET_C_LOCALE))
+ break;
+ } else {
+ for (__ns = __nf; __ns < __ne; ++__ns)
+ if (!isdigit_l(*__ns, _LIBCPP_GET_C_LOCALE))
+ break;
+ }
+ if (__grouping.empty()) {
+ __ct.widen(__nf, __ns, __oe);
+ __oe += __ns - __nf;
+ } else {
+ std::reverse(__nf, __ns);
+ _CharT __thousands_sep = __npt.thousands_sep();
+ unsigned __dc = 0;
+ unsigned __dg = 0;
+ for (char* __p = __nf; __p < __ns; ++__p) {
+ if (__grouping[__dg] > 0 && __dc == static_cast<unsigned>(__grouping[__dg])) {
+ *__oe++ = __thousands_sep;
+ __dc = 0;
+ if (__dg < __grouping.size() - 1)
+ ++__dg;
+ }
+ *__oe++ = __ct.widen(*__p);
+ ++__dc;
+ }
+ std::reverse(__ob + (__nf - __nb), __oe);
+ }
+ for (__nf = __ns; __nf < __ne; ++__nf) {
+ if (*__nf == '.') {
+ *__oe++ = __npt.decimal_point();
+ ++__nf;
+ break;
+ } else
+ *__oe++ = __ct.widen(*__nf);
+ }
+ __ct.widen(__nf, __ne, __oe);
+ __oe += __ne - __nf;
+ if (__np == __ne)
+ __op = __oe;
+ else
+ __op = __ob + (__np - __nb);
+}
+
+extern template struct _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __num_put<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template struct _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __num_put<wchar_t>;
+# endif
+
+template <class _CharT, class _OutputIterator = ostreambuf_iterator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS num_put : public locale::facet, private __num_put<_CharT> {
+public:
+ typedef _CharT char_type;
+ typedef _OutputIterator iter_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit num_put(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI iter_type put(iter_type __s, ios_base& __iob, char_type __fl, bool __v) const {
+ return do_put(__s, __iob, __fl, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type put(iter_type __s, ios_base& __iob, char_type __fl, long __v) const {
+ return do_put(__s, __iob, __fl, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type put(iter_type __s, ios_base& __iob, char_type __fl, long long __v) const {
+ return do_put(__s, __iob, __fl, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type put(iter_type __s, ios_base& __iob, char_type __fl, unsigned long __v) const {
+ return do_put(__s, __iob, __fl, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type put(iter_type __s, ios_base& __iob, char_type __fl, unsigned long long __v) const {
+ return do_put(__s, __iob, __fl, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type put(iter_type __s, ios_base& __iob, char_type __fl, double __v) const {
+ return do_put(__s, __iob, __fl, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type put(iter_type __s, ios_base& __iob, char_type __fl, long double __v) const {
+ return do_put(__s, __iob, __fl, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type put(iter_type __s, ios_base& __iob, char_type __fl, const void* __v) const {
+ return do_put(__s, __iob, __fl, __v);
+ }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~num_put() override {}
+
+ virtual iter_type do_put(iter_type __s, ios_base& __iob, char_type __fl, bool __v) const;
+ virtual iter_type do_put(iter_type __s, ios_base& __iob, char_type __fl, long __v) const;
+ virtual iter_type do_put(iter_type __s, ios_base& __iob, char_type __fl, long long __v) const;
+ virtual iter_type do_put(iter_type __s, ios_base& __iob, char_type __fl, unsigned long) const;
+ virtual iter_type do_put(iter_type __s, ios_base& __iob, char_type __fl, unsigned long long) const;
+ virtual iter_type do_put(iter_type __s, ios_base& __iob, char_type __fl, double __v) const;
+ virtual iter_type do_put(iter_type __s, ios_base& __iob, char_type __fl, long double __v) const;
+ virtual iter_type do_put(iter_type __s, ios_base& __iob, char_type __fl, const void* __v) const;
+
+ template <class _Integral>
+ _LIBCPP_HIDE_FROM_ABI inline _OutputIterator
+ __do_put_integral(iter_type __s, ios_base& __iob, char_type __fl, _Integral __v, char const* __len) const;
+
+ template <class _Float>
+ _LIBCPP_HIDE_FROM_ABI inline _OutputIterator
+ __do_put_floating_point(iter_type __s, ios_base& __iob, char_type __fl, _Float __v, char const* __len) const;
+};
+
+template <class _CharT, class _OutputIterator>
+locale::id num_put<_CharT, _OutputIterator>::id;
+
+template <class _CharT, class _OutputIterator>
+_LIBCPP_HIDE_FROM_ABI _OutputIterator __pad_and_output(
+ _OutputIterator __s, const _CharT* __ob, const _CharT* __op, const _CharT* __oe, ios_base& __iob, _CharT __fl) {
+ streamsize __sz = __oe - __ob;
+ streamsize __ns = __iob.width();
+ if (__ns > __sz)
+ __ns -= __sz;
+ else
+ __ns = 0;
+ for (; __ob < __op; ++__ob, ++__s)
+ *__s = *__ob;
+ for (; __ns; --__ns, ++__s)
+ *__s = __fl;
+ for (; __ob < __oe; ++__ob, ++__s)
+ *__s = *__ob;
+ __iob.width(0);
+ return __s;
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI ostreambuf_iterator<_CharT, _Traits> __pad_and_output(
+ ostreambuf_iterator<_CharT, _Traits> __s,
+ const _CharT* __ob,
+ const _CharT* __op,
+ const _CharT* __oe,
+ ios_base& __iob,
+ _CharT __fl) {
+ if (__s.__sbuf_ == nullptr)
+ return __s;
+ streamsize __sz = __oe - __ob;
+ streamsize __ns = __iob.width();
+ if (__ns > __sz)
+ __ns -= __sz;
+ else
+ __ns = 0;
+ streamsize __np = __op - __ob;
+ if (__np > 0) {
+ if (__s.__sbuf_->sputn(__ob, __np) != __np) {
+ __s.__sbuf_ = nullptr;
+ return __s;
+ }
+ }
+ if (__ns > 0) {
+ basic_string<_CharT, _Traits> __sp(__ns, __fl);
+ if (__s.__sbuf_->sputn(__sp.data(), __ns) != __ns) {
+ __s.__sbuf_ = nullptr;
+ return __s;
+ }
+ }
+ __np = __oe - __op;
+ if (__np > 0) {
+ if (__s.__sbuf_->sputn(__op, __np) != __np) {
+ __s.__sbuf_ = nullptr;
+ return __s;
+ }
+ }
+ __iob.width(0);
+ return __s;
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator
+num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob, char_type __fl, bool __v) const {
+ if ((__iob.flags() & ios_base::boolalpha) == 0)
+ return do_put(__s, __iob, __fl, (unsigned long)__v);
+ const numpunct<char_type>& __np = std::use_facet<numpunct<char_type> >(__iob.getloc());
+ typedef typename numpunct<char_type>::string_type string_type;
+ string_type __nm = __v ? __np.truename() : __np.falsename();
+ for (typename string_type::iterator __i = __nm.begin(); __i != __nm.end(); ++__i, ++__s)
+ *__s = *__i;
+ return __s;
+}
+
+template <class _CharT, class _OutputIterator>
+template <class _Integral>
+_LIBCPP_HIDE_FROM_ABI inline _OutputIterator num_put<_CharT, _OutputIterator>::__do_put_integral(
+ iter_type __s, ios_base& __iob, char_type __fl, _Integral __v, char const* __len) const {
+ // Stage 1 - Get number in narrow char
+ char __fmt[8] = {'%', 0};
+ this->__format_int(__fmt + 1, __len, is_signed<_Integral>::value, __iob.flags());
+ // Worst case is octal, with showbase enabled. Note that octal is always
+ // printed as an unsigned value.
+ using _Unsigned = typename make_unsigned<_Integral>::type;
+ _LIBCPP_CONSTEXPR const unsigned __nbuf =
+ (numeric_limits<_Unsigned>::digits / 3) // 1 char per 3 bits
+ + ((numeric_limits<_Unsigned>::digits % 3) != 0) // round up
+ + 2; // base prefix + terminating null character
+ char __nar[__nbuf];
+ _LIBCPP_DIAGNOSTIC_PUSH
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wformat-nonliteral")
+ _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wformat-nonliteral")
+ int __nc = __libcpp_snprintf_l(__nar, sizeof(__nar), _LIBCPP_GET_C_LOCALE, __fmt, __v);
+ _LIBCPP_DIAGNOSTIC_POP
+ char* __ne = __nar + __nc;
+ char* __np = this->__identify_padding(__nar, __ne, __iob);
+ // Stage 2 - Widen __nar while adding thousands separators
+ char_type __o[2 * (__nbuf - 1) - 1];
+ char_type* __op; // pad here
+ char_type* __oe; // end of output
+ this->__widen_and_group_int(__nar, __np, __ne, __o, __op, __oe, __iob.getloc());
+ // [__o, __oe) contains thousands_sep'd wide number
+ // Stage 3 & 4
+ return std::__pad_and_output(__s, __o, __op, __oe, __iob, __fl);
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator
+num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob, char_type __fl, long __v) const {
+ return this->__do_put_integral(__s, __iob, __fl, __v, "l");
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator
+num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob, char_type __fl, long long __v) const {
+ return this->__do_put_integral(__s, __iob, __fl, __v, "ll");
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator
+num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob, char_type __fl, unsigned long __v) const {
+ return this->__do_put_integral(__s, __iob, __fl, __v, "l");
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator
+num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob, char_type __fl, unsigned long long __v) const {
+ return this->__do_put_integral(__s, __iob, __fl, __v, "ll");
+}
+
+template <class _CharT, class _OutputIterator>
+template <class _Float>
+_LIBCPP_HIDE_FROM_ABI inline _OutputIterator num_put<_CharT, _OutputIterator>::__do_put_floating_point(
+ iter_type __s, ios_base& __iob, char_type __fl, _Float __v, char const* __len) const {
+ // Stage 1 - Get number in narrow char
+ char __fmt[8] = {'%', 0};
+ bool __specify_precision = this->__format_float(__fmt + 1, __len, __iob.flags());
+ const unsigned __nbuf = 30;
+ char __nar[__nbuf];
+ char* __nb = __nar;
+ int __nc;
+ _LIBCPP_DIAGNOSTIC_PUSH
+ _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wformat-nonliteral")
+ _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wformat-nonliteral")
+ if (__specify_precision)
+ __nc = __libcpp_snprintf_l(__nb, __nbuf, _LIBCPP_GET_C_LOCALE, __fmt, (int)__iob.precision(), __v);
+ else
+ __nc = __libcpp_snprintf_l(__nb, __nbuf, _LIBCPP_GET_C_LOCALE, __fmt, __v);
+ unique_ptr<char, void (*)(void*)> __nbh(nullptr, free);
+ if (__nc > static_cast<int>(__nbuf - 1)) {
+ if (__specify_precision)
+ __nc = __libcpp_asprintf_l(&__nb, _LIBCPP_GET_C_LOCALE, __fmt, (int)__iob.precision(), __v);
+ else
+ __nc = __libcpp_asprintf_l(&__nb, _LIBCPP_GET_C_LOCALE, __fmt, __v);
+ if (__nc == -1)
+ __throw_bad_alloc();
+ __nbh.reset(__nb);
+ }
+ _LIBCPP_DIAGNOSTIC_POP
+ char* __ne = __nb + __nc;
+ char* __np = this->__identify_padding(__nb, __ne, __iob);
+ // Stage 2 - Widen __nar while adding thousands separators
+ char_type __o[2 * (__nbuf - 1) - 1];
+ char_type* __ob = __o;
+ unique_ptr<char_type, void (*)(void*)> __obh(0, free);
+ if (__nb != __nar) {
+ __ob = (char_type*)malloc(2 * static_cast<size_t>(__nc) * sizeof(char_type));
+ if (__ob == 0)
+ __throw_bad_alloc();
+ __obh.reset(__ob);
+ }
+ char_type* __op; // pad here
+ char_type* __oe; // end of output
+ this->__widen_and_group_float(__nb, __np, __ne, __ob, __op, __oe, __iob.getloc());
+ // [__o, __oe) contains thousands_sep'd wide number
+ // Stage 3 & 4
+ __s = std::__pad_and_output(__s, __ob, __op, __oe, __iob, __fl);
+ return __s;
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator
+num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob, char_type __fl, double __v) const {
+ return this->__do_put_floating_point(__s, __iob, __fl, __v, "");
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator
+num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob, char_type __fl, long double __v) const {
+ return this->__do_put_floating_point(__s, __iob, __fl, __v, "L");
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator
+num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob, char_type __fl, const void* __v) const {
+ // Stage 1 - Get pointer in narrow char
+ const unsigned __nbuf = 20;
+ char __nar[__nbuf];
+ int __nc = __libcpp_snprintf_l(__nar, sizeof(__nar), _LIBCPP_GET_C_LOCALE, "%p", __v);
+ char* __ne = __nar + __nc;
+ char* __np = this->__identify_padding(__nar, __ne, __iob);
+ // Stage 2 - Widen __nar
+ char_type __o[2 * (__nbuf - 1) - 1];
+ char_type* __op; // pad here
+ char_type* __oe; // end of output
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__iob.getloc());
+ __ct.widen(__nar, __ne, __o);
+ __oe = __o + (__ne - __nar);
+ if (__np == __ne)
+ __op = __oe;
+ else
+ __op = __o + (__np - __nar);
+ // [__o, __oe) contains wide number
+ // Stage 3 & 4
+ return std::__pad_and_output(__s, __o, __op, __oe, __iob, __fl);
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS num_put<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS num_put<wchar_t>;
+# endif
+
+template <class _CharT, class _InputIterator>
+_LIBCPP_HIDE_FROM_ABI int __get_up_to_n_digits(
+ _InputIterator& __b, _InputIterator __e, ios_base::iostate& __err, const ctype<_CharT>& __ct, int __n) {
+ // Precondition: __n >= 1
+ if (__b == __e) {
+ __err |= ios_base::eofbit | ios_base::failbit;
+ return 0;
+ }
+ // get first digit
+ _CharT __c = *__b;
+ if (!__ct.is(ctype_base::digit, __c)) {
+ __err |= ios_base::failbit;
+ return 0;
+ }
+ int __r = __ct.narrow(__c, 0) - '0';
+ for (++__b, (void)--__n; __b != __e && __n > 0; ++__b, (void)--__n) {
+ // get next digit
+ __c = *__b;
+ if (!__ct.is(ctype_base::digit, __c))
+ return __r;
+ __r = __r * 10 + __ct.narrow(__c, 0) - '0';
+ }
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ return __r;
+}
+
+class _LIBCPP_EXPORTED_FROM_ABI time_base {
+public:
+ enum dateorder { no_order, dmy, mdy, ymd, ydm };
+};
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS __time_get_c_storage {
+protected:
+ typedef basic_string<_CharT> string_type;
+
+ virtual const string_type* __weeks() const;
+ virtual const string_type* __months() const;
+ virtual const string_type* __am_pm() const;
+ virtual const string_type& __c() const;
+ virtual const string_type& __r() const;
+ virtual const string_type& __x() const;
+ virtual const string_type& __X() const;
+
+ _LIBCPP_HIDE_FROM_ABI ~__time_get_c_storage() {}
+};
+
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const string* __time_get_c_storage<char>::__weeks() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const string* __time_get_c_storage<char>::__months() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const string* __time_get_c_storage<char>::__am_pm() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const string& __time_get_c_storage<char>::__c() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const string& __time_get_c_storage<char>::__r() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const string& __time_get_c_storage<char>::__x() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const string& __time_get_c_storage<char>::__X() const;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const wstring* __time_get_c_storage<wchar_t>::__weeks() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const wstring* __time_get_c_storage<wchar_t>::__months() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const wstring* __time_get_c_storage<wchar_t>::__am_pm() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const wstring& __time_get_c_storage<wchar_t>::__c() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const wstring& __time_get_c_storage<wchar_t>::__r() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const wstring& __time_get_c_storage<wchar_t>::__x() const;
+template <>
+_LIBCPP_EXPORTED_FROM_ABI const wstring& __time_get_c_storage<wchar_t>::__X() const;
+# endif
+
+template <class _CharT, class _InputIterator = istreambuf_iterator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS time_get : public locale::facet, public time_base, private __time_get_c_storage<_CharT> {
+public:
+ typedef _CharT char_type;
+ typedef _InputIterator iter_type;
+ typedef time_base::dateorder dateorder;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit time_get(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI dateorder date_order() const { return this->do_date_order(); }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get_time(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ return do_get_time(__b, __e, __iob, __err, __tm);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get_date(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ return do_get_date(__b, __e, __iob, __err, __tm);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get_weekday(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ return do_get_weekday(__b, __e, __iob, __err, __tm);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get_monthname(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ return do_get_monthname(__b, __e, __iob, __err, __tm);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get_year(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ return do_get_year(__b, __e, __iob, __err, __tm);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm, char __fmt, char __mod = 0)
+ const {
+ return do_get(__b, __e, __iob, __err, __tm, __fmt, __mod);
+ }
+
+ iter_type
+ get(iter_type __b,
+ iter_type __e,
+ ios_base& __iob,
+ ios_base::iostate& __err,
+ tm* __tm,
+ const char_type* __fmtb,
+ const char_type* __fmte) const;
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~time_get() override {}
+
+ virtual dateorder do_date_order() const;
+ virtual iter_type
+ do_get_time(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const;
+ virtual iter_type
+ do_get_date(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const;
+ virtual iter_type
+ do_get_weekday(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const;
+ virtual iter_type
+ do_get_monthname(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const;
+ virtual iter_type
+ do_get_year(iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const;
+ virtual iter_type do_get(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm, char __fmt, char __mod) const;
+
+private:
+ void __get_white_space(iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void __get_percent(iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+
+ void __get_weekdayname(
+ int& __m, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void __get_monthname(
+ int& __m, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void __get_day(int& __d, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_month(int& __m, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_year(int& __y, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_year4(int& __y, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_hour(int& __d, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_12_hour(int& __h, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_am_pm(int& __h, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_minute(int& __m, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_second(int& __s, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void
+ __get_weekday(int& __w, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+ void __get_day_year_num(
+ int& __w, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const;
+};
+
+template <class _CharT, class _InputIterator>
+locale::id time_get<_CharT, _InputIterator>::id;
+
+// time_get primitives
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_weekdayname(
+ int& __w, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ // Note: ignoring case comes from the POSIX strptime spec
+ const string_type* __wk = this->__weeks();
+ ptrdiff_t __i = std::__scan_keyword(__b, __e, __wk, __wk + 14, __ct, __err, false) - __wk;
+ if (__i < 14)
+ __w = __i % 7;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_monthname(
+ int& __m, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ // Note: ignoring case comes from the POSIX strptime spec
+ const string_type* __month = this->__months();
+ ptrdiff_t __i = std::__scan_keyword(__b, __e, __month, __month + 24, __ct, __err, false) - __month;
+ if (__i < 24)
+ __m = __i % 12;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_day(
+ int& __d, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 2);
+ if (!(__err & ios_base::failbit) && 1 <= __t && __t <= 31)
+ __d = __t;
+ else
+ __err |= ios_base::failbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_month(
+ int& __m, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 2) - 1;
+ if (!(__err & ios_base::failbit) && 0 <= __t && __t <= 11)
+ __m = __t;
+ else
+ __err |= ios_base::failbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_year(
+ int& __y, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 4);
+ if (!(__err & ios_base::failbit)) {
+ if (__t < 69)
+ __t += 2000;
+ else if (69 <= __t && __t <= 99)
+ __t += 1900;
+ __y = __t - 1900;
+ }
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_year4(
+ int& __y, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 4);
+ if (!(__err & ios_base::failbit))
+ __y = __t - 1900;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_hour(
+ int& __h, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 2);
+ if (!(__err & ios_base::failbit) && __t <= 23)
+ __h = __t;
+ else
+ __err |= ios_base::failbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_12_hour(
+ int& __h, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 2);
+ if (!(__err & ios_base::failbit) && 1 <= __t && __t <= 12)
+ __h = __t;
+ else
+ __err |= ios_base::failbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_minute(
+ int& __m, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 2);
+ if (!(__err & ios_base::failbit) && __t <= 59)
+ __m = __t;
+ else
+ __err |= ios_base::failbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_second(
+ int& __s, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 2);
+ if (!(__err & ios_base::failbit) && __t <= 60)
+ __s = __t;
+ else
+ __err |= ios_base::failbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_weekday(
+ int& __w, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 1);
+ if (!(__err & ios_base::failbit) && __t <= 6)
+ __w = __t;
+ else
+ __err |= ios_base::failbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_day_year_num(
+ int& __d, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ int __t = std::__get_up_to_n_digits(__b, __e, __err, __ct, 3);
+ if (!(__err & ios_base::failbit) && __t <= 365)
+ __d = __t;
+ else
+ __err |= ios_base::failbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_white_space(
+ iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ for (; __b != __e && __ct.is(ctype_base::space, *__b); ++__b)
+ ;
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_am_pm(
+ int& __h, iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ const string_type* __ap = this->__am_pm();
+ if (__ap[0].size() + __ap[1].size() == 0) {
+ __err |= ios_base::failbit;
+ return;
+ }
+ ptrdiff_t __i = std::__scan_keyword(__b, __e, __ap, __ap + 2, __ct, __err, false) - __ap;
+ if (__i == 0 && __h == 12)
+ __h = 0;
+ else if (__i == 1 && __h < 12)
+ __h += 12;
+}
+
+template <class _CharT, class _InputIterator>
+void time_get<_CharT, _InputIterator>::__get_percent(
+ iter_type& __b, iter_type __e, ios_base::iostate& __err, const ctype<char_type>& __ct) const {
+ if (__b == __e) {
+ __err |= ios_base::eofbit | ios_base::failbit;
+ return;
+ }
+ if (__ct.narrow(*__b, 0) != '%')
+ __err |= ios_base::failbit;
+ else if (++__b == __e)
+ __err |= ios_base::eofbit;
+}
+
+// time_get end primitives
+
+template <class _CharT, class _InputIterator>
+_InputIterator time_get<_CharT, _InputIterator>::get(
+ iter_type __b,
+ iter_type __e,
+ ios_base& __iob,
+ ios_base::iostate& __err,
+ tm* __tm,
+ const char_type* __fmtb,
+ const char_type* __fmte) const {
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__iob.getloc());
+ __err = ios_base::goodbit;
+ while (__fmtb != __fmte && __err == ios_base::goodbit) {
+ if (__b == __e) {
+ __err = ios_base::failbit;
+ break;
+ }
+ if (__ct.narrow(*__fmtb, 0) == '%') {
+ if (++__fmtb == __fmte) {
+ __err = ios_base::failbit;
+ break;
+ }
+ char __cmd = __ct.narrow(*__fmtb, 0);
+ char __opt = '\0';
+ if (__cmd == 'E' || __cmd == '0') {
+ if (++__fmtb == __fmte) {
+ __err = ios_base::failbit;
+ break;
+ }
+ __opt = __cmd;
+ __cmd = __ct.narrow(*__fmtb, 0);
+ }
+ __b = do_get(__b, __e, __iob, __err, __tm, __cmd, __opt);
+ ++__fmtb;
+ } else if (__ct.is(ctype_base::space, *__fmtb)) {
+ for (++__fmtb; __fmtb != __fmte && __ct.is(ctype_base::space, *__fmtb); ++__fmtb)
+ ;
+ for (; __b != __e && __ct.is(ctype_base::space, *__b); ++__b)
+ ;
+ } else if (__ct.toupper(*__b) == __ct.toupper(*__fmtb)) {
+ ++__b;
+ ++__fmtb;
+ } else
+ __err = ios_base::failbit;
+ }
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ return __b;
+}
+
+template <class _CharT, class _InputIterator>
+typename time_get<_CharT, _InputIterator>::dateorder time_get<_CharT, _InputIterator>::do_date_order() const {
+ return mdy;
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator time_get<_CharT, _InputIterator>::do_get_time(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ const char_type __fmt[] = {'%', 'H', ':', '%', 'M', ':', '%', 'S'};
+ return get(__b, __e, __iob, __err, __tm, __fmt, __fmt + sizeof(__fmt) / sizeof(__fmt[0]));
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator time_get<_CharT, _InputIterator>::do_get_date(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ const string_type& __fmt = this->__x();
+ return get(__b, __e, __iob, __err, __tm, __fmt.data(), __fmt.data() + __fmt.size());
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator time_get<_CharT, _InputIterator>::do_get_weekday(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__iob.getloc());
+ __get_weekdayname(__tm->tm_wday, __b, __e, __err, __ct);
+ return __b;
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator time_get<_CharT, _InputIterator>::do_get_monthname(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__iob.getloc());
+ __get_monthname(__tm->tm_mon, __b, __e, __err, __ct);
+ return __b;
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator time_get<_CharT, _InputIterator>::do_get_year(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm) const {
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__iob.getloc());
+ __get_year(__tm->tm_year, __b, __e, __err, __ct);
+ return __b;
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator time_get<_CharT, _InputIterator>::do_get(
+ iter_type __b, iter_type __e, ios_base& __iob, ios_base::iostate& __err, tm* __tm, char __fmt, char) const {
+ __err = ios_base::goodbit;
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__iob.getloc());
+ switch (__fmt) {
+ case 'a':
+ case 'A':
+ __get_weekdayname(__tm->tm_wday, __b, __e, __err, __ct);
+ break;
+ case 'b':
+ case 'B':
+ case 'h':
+ __get_monthname(__tm->tm_mon, __b, __e, __err, __ct);
+ break;
+ case 'c': {
+ const string_type& __fm = this->__c();
+ __b = get(__b, __e, __iob, __err, __tm, __fm.data(), __fm.data() + __fm.size());
+ } break;
+ case 'd':
+ case 'e':
+ __get_day(__tm->tm_mday, __b, __e, __err, __ct);
+ break;
+ case 'D': {
+ const char_type __fm[] = {'%', 'm', '/', '%', 'd', '/', '%', 'y'};
+ __b = get(__b, __e, __iob, __err, __tm, __fm, __fm + sizeof(__fm) / sizeof(__fm[0]));
+ } break;
+ case 'F': {
+ const char_type __fm[] = {'%', 'Y', '-', '%', 'm', '-', '%', 'd'};
+ __b = get(__b, __e, __iob, __err, __tm, __fm, __fm + sizeof(__fm) / sizeof(__fm[0]));
+ } break;
+ case 'H':
+ __get_hour(__tm->tm_hour, __b, __e, __err, __ct);
+ break;
+ case 'I':
+ __get_12_hour(__tm->tm_hour, __b, __e, __err, __ct);
+ break;
+ case 'j':
+ __get_day_year_num(__tm->tm_yday, __b, __e, __err, __ct);
+ break;
+ case 'm':
+ __get_month(__tm->tm_mon, __b, __e, __err, __ct);
+ break;
+ case 'M':
+ __get_minute(__tm->tm_min, __b, __e, __err, __ct);
+ break;
+ case 'n':
+ case 't':
+ __get_white_space(__b, __e, __err, __ct);
+ break;
+ case 'p':
+ __get_am_pm(__tm->tm_hour, __b, __e, __err, __ct);
+ break;
+ case 'r': {
+ const char_type __fm[] = {'%', 'I', ':', '%', 'M', ':', '%', 'S', ' ', '%', 'p'};
+ __b = get(__b, __e, __iob, __err, __tm, __fm, __fm + sizeof(__fm) / sizeof(__fm[0]));
+ } break;
+ case 'R': {
+ const char_type __fm[] = {'%', 'H', ':', '%', 'M'};
+ __b = get(__b, __e, __iob, __err, __tm, __fm, __fm + sizeof(__fm) / sizeof(__fm[0]));
+ } break;
+ case 'S':
+ __get_second(__tm->tm_sec, __b, __e, __err, __ct);
+ break;
+ case 'T': {
+ const char_type __fm[] = {'%', 'H', ':', '%', 'M', ':', '%', 'S'};
+ __b = get(__b, __e, __iob, __err, __tm, __fm, __fm + sizeof(__fm) / sizeof(__fm[0]));
+ } break;
+ case 'w':
+ __get_weekday(__tm->tm_wday, __b, __e, __err, __ct);
+ break;
+ case 'x':
+ return do_get_date(__b, __e, __iob, __err, __tm);
+ case 'X': {
+ const string_type& __fm = this->__X();
+ __b = get(__b, __e, __iob, __err, __tm, __fm.data(), __fm.data() + __fm.size());
+ } break;
+ case 'y':
+ __get_year(__tm->tm_year, __b, __e, __err, __ct);
+ break;
+ case 'Y':
+ __get_year4(__tm->tm_year, __b, __e, __err, __ct);
+ break;
+ case '%':
+ __get_percent(__b, __e, __err, __ct);
+ break;
+ default:
+ __err |= ios_base::failbit;
+ }
+ return __b;
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS time_get<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS time_get<wchar_t>;
+# endif
+
+class _LIBCPP_EXPORTED_FROM_ABI __time_get {
+protected:
+ locale_t __loc_;
+
+ __time_get(const char* __nm);
+ __time_get(const string& __nm);
+ ~__time_get();
+};
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS __time_get_storage : public __time_get {
+protected:
+ typedef basic_string<_CharT> string_type;
+
+ string_type __weeks_[14];
+ string_type __months_[24];
+ string_type __am_pm_[2];
+ string_type __c_;
+ string_type __r_;
+ string_type __x_;
+ string_type __X_;
+
+ explicit __time_get_storage(const char* __nm);
+ explicit __time_get_storage(const string& __nm);
+
+ _LIBCPP_HIDE_FROM_ABI ~__time_get_storage() {}
+
+ time_base::dateorder __do_date_order() const;
+
+private:
+ void init(const ctype<_CharT>&);
+ string_type __analyze(char __fmt, const ctype<_CharT>&);
+};
+
+# define _LIBCPP_TIME_GET_STORAGE_EXPLICIT_INSTANTIATION(_CharT) \
+ template <> \
+ _LIBCPP_EXPORTED_FROM_ABI time_base::dateorder __time_get_storage<_CharT>::__do_date_order() const; \
+ template <> \
+ _LIBCPP_EXPORTED_FROM_ABI __time_get_storage<_CharT>::__time_get_storage(const char*); \
+ template <> \
+ _LIBCPP_EXPORTED_FROM_ABI __time_get_storage<_CharT>::__time_get_storage(const string&); \
+ template <> \
+ _LIBCPP_EXPORTED_FROM_ABI void __time_get_storage<_CharT>::init(const ctype<_CharT>&); \
+ template <> \
+ _LIBCPP_EXPORTED_FROM_ABI __time_get_storage<_CharT>::string_type __time_get_storage<_CharT>::__analyze( \
+ char, const ctype<_CharT>&); \
+ extern template _LIBCPP_EXPORTED_FROM_ABI time_base::dateorder __time_get_storage<_CharT>::__do_date_order() \
+ const; \
+ extern template _LIBCPP_EXPORTED_FROM_ABI __time_get_storage<_CharT>::__time_get_storage(const char*); \
+ extern template _LIBCPP_EXPORTED_FROM_ABI __time_get_storage<_CharT>::__time_get_storage(const string&); \
+ extern template _LIBCPP_EXPORTED_FROM_ABI void __time_get_storage<_CharT>::init(const ctype<_CharT>&); \
+ extern template _LIBCPP_EXPORTED_FROM_ABI __time_get_storage<_CharT>::string_type \
+ __time_get_storage<_CharT>::__analyze(char, const ctype<_CharT>&); \
+ /**/
+
+_LIBCPP_TIME_GET_STORAGE_EXPLICIT_INSTANTIATION(char)
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+_LIBCPP_TIME_GET_STORAGE_EXPLICIT_INSTANTIATION(wchar_t)
+# endif
+# undef _LIBCPP_TIME_GET_STORAGE_EXPLICIT_INSTANTIATION
+
+template <class _CharT, class _InputIterator = istreambuf_iterator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS time_get_byname
+ : public time_get<_CharT, _InputIterator>,
+ private __time_get_storage<_CharT> {
+public:
+ typedef time_base::dateorder dateorder;
+ typedef _InputIterator iter_type;
+ typedef _CharT char_type;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit time_get_byname(const char* __nm, size_t __refs = 0)
+ : time_get<_CharT, _InputIterator>(__refs), __time_get_storage<_CharT>(__nm) {}
+ _LIBCPP_HIDE_FROM_ABI explicit time_get_byname(const string& __nm, size_t __refs = 0)
+ : time_get<_CharT, _InputIterator>(__refs), __time_get_storage<_CharT>(__nm) {}
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~time_get_byname() override {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL dateorder do_date_order() const override { return this->__do_date_order(); }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const string_type* __weeks() const override { return this->__weeks_; }
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const string_type* __months() const override { return this->__months_; }
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const string_type* __am_pm() const override { return this->__am_pm_; }
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const string_type& __c() const override { return this->__c_; }
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const string_type& __r() const override { return this->__r_; }
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const string_type& __x() const override { return this->__x_; }
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL const string_type& __X() const override { return this->__X_; }
+};
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS time_get_byname<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS time_get_byname<wchar_t>;
+# endif
+
+class _LIBCPP_EXPORTED_FROM_ABI __time_put {
+ locale_t __loc_;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI __time_put() : __loc_(_LIBCPP_GET_C_LOCALE) {}
+ __time_put(const char* __nm);
+ __time_put(const string& __nm);
+ ~__time_put();
+ void __do_put(char* __nb, char*& __ne, const tm* __tm, char __fmt, char __mod) const;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ void __do_put(wchar_t* __wb, wchar_t*& __we, const tm* __tm, char __fmt, char __mod) const;
+# endif
+};
+
+template <class _CharT, class _OutputIterator = ostreambuf_iterator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS time_put : public locale::facet, private __time_put {
+public:
+ typedef _CharT char_type;
+ typedef _OutputIterator iter_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit time_put(size_t __refs = 0) : locale::facet(__refs) {}
+
+ iter_type
+ put(iter_type __s, ios_base& __iob, char_type __fl, const tm* __tm, const char_type* __pb, const char_type* __pe)
+ const;
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ put(iter_type __s, ios_base& __iob, char_type __fl, const tm* __tm, char __fmt, char __mod = 0) const {
+ return do_put(__s, __iob, __fl, __tm, __fmt, __mod);
+ }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~time_put() override {}
+ virtual iter_type do_put(iter_type __s, ios_base&, char_type, const tm* __tm, char __fmt, char __mod) const;
+
+ _LIBCPP_HIDE_FROM_ABI explicit time_put(const char* __nm, size_t __refs) : locale::facet(__refs), __time_put(__nm) {}
+ _LIBCPP_HIDE_FROM_ABI explicit time_put(const string& __nm, size_t __refs)
+ : locale::facet(__refs), __time_put(__nm) {}
+};
+
+template <class _CharT, class _OutputIterator>
+locale::id time_put<_CharT, _OutputIterator>::id;
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator time_put<_CharT, _OutputIterator>::put(
+ iter_type __s, ios_base& __iob, char_type __fl, const tm* __tm, const char_type* __pb, const char_type* __pe)
+ const {
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__iob.getloc());
+ for (; __pb != __pe; ++__pb) {
+ if (__ct.narrow(*__pb, 0) == '%') {
+ if (++__pb == __pe) {
+ *__s++ = __pb[-1];
+ break;
+ }
+ char __mod = 0;
+ char __fmt = __ct.narrow(*__pb, 0);
+ if (__fmt == 'E' || __fmt == 'O') {
+ if (++__pb == __pe) {
+ *__s++ = __pb[-2];
+ *__s++ = __pb[-1];
+ break;
+ }
+ __mod = __fmt;
+ __fmt = __ct.narrow(*__pb, 0);
+ }
+ __s = do_put(__s, __iob, __fl, __tm, __fmt, __mod);
+ } else
+ *__s++ = *__pb;
+ }
+ return __s;
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator time_put<_CharT, _OutputIterator>::do_put(
+ iter_type __s, ios_base&, char_type, const tm* __tm, char __fmt, char __mod) const {
+ char_type __nar[100];
+ char_type* __nb = __nar;
+ char_type* __ne = __nb + 100;
+ __do_put(__nb, __ne, __tm, __fmt, __mod);
+ return std::copy(__nb, __ne, __s);
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS time_put<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS time_put<wchar_t>;
+# endif
+
+template <class _CharT, class _OutputIterator = ostreambuf_iterator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS time_put_byname : public time_put<_CharT, _OutputIterator> {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit time_put_byname(const char* __nm, size_t __refs = 0)
+ : time_put<_CharT, _OutputIterator>(__nm, __refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit time_put_byname(const string& __nm, size_t __refs = 0)
+ : time_put<_CharT, _OutputIterator>(__nm, __refs) {}
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~time_put_byname() override {}
+};
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS time_put_byname<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS time_put_byname<wchar_t>;
+# endif
+
+// money_base
+
+class _LIBCPP_EXPORTED_FROM_ABI money_base {
+public:
+ enum part { none, space, symbol, sign, value };
+ struct pattern {
+ char field[4];
+ };
+
+ _LIBCPP_HIDE_FROM_ABI money_base() {}
+};
+
+// moneypunct
+
+template <class _CharT, bool _International = false>
+class _LIBCPP_TEMPLATE_VIS moneypunct : public locale::facet, public money_base {
+public:
+ typedef _CharT char_type;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit moneypunct(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI char_type decimal_point() const { return do_decimal_point(); }
+ _LIBCPP_HIDE_FROM_ABI char_type thousands_sep() const { return do_thousands_sep(); }
+ _LIBCPP_HIDE_FROM_ABI string grouping() const { return do_grouping(); }
+ _LIBCPP_HIDE_FROM_ABI string_type curr_symbol() const { return do_curr_symbol(); }
+ _LIBCPP_HIDE_FROM_ABI string_type positive_sign() const { return do_positive_sign(); }
+ _LIBCPP_HIDE_FROM_ABI string_type negative_sign() const { return do_negative_sign(); }
+ _LIBCPP_HIDE_FROM_ABI int frac_digits() const { return do_frac_digits(); }
+ _LIBCPP_HIDE_FROM_ABI pattern pos_format() const { return do_pos_format(); }
+ _LIBCPP_HIDE_FROM_ABI pattern neg_format() const { return do_neg_format(); }
+
+ static locale::id id;
+ static const bool intl = _International;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~moneypunct() override {}
+
+ virtual char_type do_decimal_point() const { return numeric_limits<char_type>::max(); }
+ virtual char_type do_thousands_sep() const { return numeric_limits<char_type>::max(); }
+ virtual string do_grouping() const { return string(); }
+ virtual string_type do_curr_symbol() const { return string_type(); }
+ virtual string_type do_positive_sign() const { return string_type(); }
+ virtual string_type do_negative_sign() const { return string_type(1, '-'); }
+ virtual int do_frac_digits() const { return 0; }
+ virtual pattern do_pos_format() const {
+ pattern __p = {{symbol, sign, none, value}};
+ return __p;
+ }
+ virtual pattern do_neg_format() const {
+ pattern __p = {{symbol, sign, none, value}};
+ return __p;
+ }
+};
+
+template <class _CharT, bool _International>
+locale::id moneypunct<_CharT, _International>::id;
+
+template <class _CharT, bool _International>
+const bool moneypunct<_CharT, _International>::intl;
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS moneypunct<char, false>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS moneypunct<char, true>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS moneypunct<wchar_t, false>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS moneypunct<wchar_t, true>;
+# endif
+
+// moneypunct_byname
+
+template <class _CharT, bool _International = false>
+class _LIBCPP_TEMPLATE_VIS moneypunct_byname : public moneypunct<_CharT, _International> {
+public:
+ typedef money_base::pattern pattern;
+ typedef _CharT char_type;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit moneypunct_byname(const char* __nm, size_t __refs = 0)
+ : moneypunct<_CharT, _International>(__refs) {
+ init(__nm);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit moneypunct_byname(const string& __nm, size_t __refs = 0)
+ : moneypunct<_CharT, _International>(__refs) {
+ init(__nm.c_str());
+ }
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~moneypunct_byname() override {}
+
+ char_type do_decimal_point() const override { return __decimal_point_; }
+ char_type do_thousands_sep() const override { return __thousands_sep_; }
+ string do_grouping() const override { return __grouping_; }
+ string_type do_curr_symbol() const override { return __curr_symbol_; }
+ string_type do_positive_sign() const override { return __positive_sign_; }
+ string_type do_negative_sign() const override { return __negative_sign_; }
+ int do_frac_digits() const override { return __frac_digits_; }
+ pattern do_pos_format() const override { return __pos_format_; }
+ pattern do_neg_format() const override { return __neg_format_; }
+
+private:
+ char_type __decimal_point_;
+ char_type __thousands_sep_;
+ string __grouping_;
+ string_type __curr_symbol_;
+ string_type __positive_sign_;
+ string_type __negative_sign_;
+ int __frac_digits_;
+ pattern __pos_format_;
+ pattern __neg_format_;
+
+ void init(const char*);
+};
+
+template <>
+_LIBCPP_EXPORTED_FROM_ABI void moneypunct_byname<char, false>::init(const char*);
+template <>
+_LIBCPP_EXPORTED_FROM_ABI void moneypunct_byname<char, true>::init(const char*);
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS moneypunct_byname<char, false>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS moneypunct_byname<char, true>;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+_LIBCPP_EXPORTED_FROM_ABI void moneypunct_byname<wchar_t, false>::init(const char*);
+template <>
+_LIBCPP_EXPORTED_FROM_ABI void moneypunct_byname<wchar_t, true>::init(const char*);
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS moneypunct_byname<wchar_t, false>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS moneypunct_byname<wchar_t, true>;
+# endif
+
+// money_get
+
+template <class _CharT>
+class __money_get {
+protected:
+ typedef _CharT char_type;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI __money_get() {}
+
+ static void __gather_info(
+ bool __intl,
+ const locale& __loc,
+ money_base::pattern& __pat,
+ char_type& __dp,
+ char_type& __ts,
+ string& __grp,
+ string_type& __sym,
+ string_type& __psn,
+ string_type& __nsn,
+ int& __fd);
+};
+
+template <class _CharT>
+void __money_get<_CharT>::__gather_info(
+ bool __intl,
+ const locale& __loc,
+ money_base::pattern& __pat,
+ char_type& __dp,
+ char_type& __ts,
+ string& __grp,
+ string_type& __sym,
+ string_type& __psn,
+ string_type& __nsn,
+ int& __fd) {
+ if (__intl) {
+ const moneypunct<char_type, true>& __mp = std::use_facet<moneypunct<char_type, true> >(__loc);
+ __pat = __mp.neg_format();
+ __nsn = __mp.negative_sign();
+ __psn = __mp.positive_sign();
+ __dp = __mp.decimal_point();
+ __ts = __mp.thousands_sep();
+ __grp = __mp.grouping();
+ __sym = __mp.curr_symbol();
+ __fd = __mp.frac_digits();
+ } else {
+ const moneypunct<char_type, false>& __mp = std::use_facet<moneypunct<char_type, false> >(__loc);
+ __pat = __mp.neg_format();
+ __nsn = __mp.negative_sign();
+ __psn = __mp.positive_sign();
+ __dp = __mp.decimal_point();
+ __ts = __mp.thousands_sep();
+ __grp = __mp.grouping();
+ __sym = __mp.curr_symbol();
+ __fd = __mp.frac_digits();
+ }
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __money_get<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __money_get<wchar_t>;
+# endif
+
+template <class _CharT, class _InputIterator = istreambuf_iterator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS money_get : public locale::facet, private __money_get<_CharT> {
+public:
+ typedef _CharT char_type;
+ typedef _InputIterator iter_type;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit money_get(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, bool __intl, ios_base& __iob, ios_base::iostate& __err, long double& __v) const {
+ return do_get(__b, __e, __intl, __iob, __err, __v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ get(iter_type __b, iter_type __e, bool __intl, ios_base& __iob, ios_base::iostate& __err, string_type& __v) const {
+ return do_get(__b, __e, __intl, __iob, __err, __v);
+ }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~money_get() override {}
+
+ virtual iter_type
+ do_get(iter_type __b, iter_type __e, bool __intl, ios_base& __iob, ios_base::iostate& __err, long double& __v) const;
+ virtual iter_type
+ do_get(iter_type __b, iter_type __e, bool __intl, ios_base& __iob, ios_base::iostate& __err, string_type& __v) const;
+
+private:
+ static bool __do_get(
+ iter_type& __b,
+ iter_type __e,
+ bool __intl,
+ const locale& __loc,
+ ios_base::fmtflags __flags,
+ ios_base::iostate& __err,
+ bool& __neg,
+ const ctype<char_type>& __ct,
+ unique_ptr<char_type, void (*)(void*)>& __wb,
+ char_type*& __wn,
+ char_type* __we);
+};
+
+template <class _CharT, class _InputIterator>
+locale::id money_get<_CharT, _InputIterator>::id;
+
+_LIBCPP_EXPORTED_FROM_ABI void __do_nothing(void*);
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI void __double_or_nothing(unique_ptr<_Tp, void (*)(void*)>& __b, _Tp*& __n, _Tp*& __e) {
+ bool __owns = __b.get_deleter() != __do_nothing;
+ size_t __cur_cap = static_cast<size_t>(__e - __b.get()) * sizeof(_Tp);
+ size_t __new_cap = __cur_cap < numeric_limits<size_t>::max() / 2 ? 2 * __cur_cap : numeric_limits<size_t>::max();
+ if (__new_cap == 0)
+ __new_cap = sizeof(_Tp);
+ size_t __n_off = static_cast<size_t>(__n - __b.get());
+ _Tp* __t = (_Tp*)std::realloc(__owns ? __b.get() : 0, __new_cap);
+ if (__t == 0)
+ __throw_bad_alloc();
+ if (__owns)
+ __b.release();
+ __b = unique_ptr<_Tp, void (*)(void*)>(__t, free);
+ __new_cap /= sizeof(_Tp);
+ __n = __b.get() + __n_off;
+ __e = __b.get() + __new_cap;
+}
+
+// true == success
+template <class _CharT, class _InputIterator>
+bool money_get<_CharT, _InputIterator>::__do_get(
+ iter_type& __b,
+ iter_type __e,
+ bool __intl,
+ const locale& __loc,
+ ios_base::fmtflags __flags,
+ ios_base::iostate& __err,
+ bool& __neg,
+ const ctype<char_type>& __ct,
+ unique_ptr<char_type, void (*)(void*)>& __wb,
+ char_type*& __wn,
+ char_type* __we) {
+ if (__b == __e) {
+ __err |= ios_base::failbit;
+ return false;
+ }
+ const unsigned __bz = 100;
+ unsigned __gbuf[__bz];
+ unique_ptr<unsigned, void (*)(void*)> __gb(__gbuf, __do_nothing);
+ unsigned* __gn = __gb.get();
+ unsigned* __ge = __gn + __bz;
+ money_base::pattern __pat;
+ char_type __dp;
+ char_type __ts;
+ string __grp;
+ string_type __sym;
+ string_type __psn;
+ string_type __nsn;
+ // Capture the spaces read into money_base::{space,none} so they
+ // can be compared to initial spaces in __sym.
+ string_type __spaces;
+ int __fd;
+ __money_get<_CharT>::__gather_info(__intl, __loc, __pat, __dp, __ts, __grp, __sym, __psn, __nsn, __fd);
+ const string_type* __trailing_sign = 0;
+ __wn = __wb.get();
+ for (unsigned __p = 0; __p < 4 && __b != __e; ++__p) {
+ switch (__pat.field[__p]) {
+ case money_base::space:
+ if (__p != 3) {
+ if (__ct.is(ctype_base::space, *__b))
+ __spaces.push_back(*__b++);
+ else {
+ __err |= ios_base::failbit;
+ return false;
+ }
+ }
+ _LIBCPP_FALLTHROUGH();
+ case money_base::none:
+ if (__p != 3) {
+ while (__b != __e && __ct.is(ctype_base::space, *__b))
+ __spaces.push_back(*__b++);
+ }
+ break;
+ case money_base::sign:
+ if (__psn.size() > 0 && *__b == __psn[0]) {
+ ++__b;
+ __neg = false;
+ if (__psn.size() > 1)
+ __trailing_sign = &__psn;
+ break;
+ }
+ if (__nsn.size() > 0 && *__b == __nsn[0]) {
+ ++__b;
+ __neg = true;
+ if (__nsn.size() > 1)
+ __trailing_sign = &__nsn;
+ break;
+ }
+ if (__psn.size() > 0 && __nsn.size() > 0) { // sign is required
+ __err |= ios_base::failbit;
+ return false;
+ }
+ if (__psn.size() == 0 && __nsn.size() == 0)
+ // locale has no way of specifying a sign. Use the initial value of __neg as a default
+ break;
+ __neg = (__nsn.size() == 0);
+ break;
+ case money_base::symbol: {
+ bool __more_needed =
+ __trailing_sign || (__p < 2) || (__p == 2 && __pat.field[3] != static_cast<char>(money_base::none));
+ bool __sb = (__flags & ios_base::showbase) != 0;
+ if (__sb || __more_needed) {
+ typename string_type::const_iterator __sym_space_end = __sym.begin();
+ if (__p > 0 && (__pat.field[__p - 1] == money_base::none || __pat.field[__p - 1] == money_base::space)) {
+ // Match spaces we've already read against spaces at
+ // the beginning of __sym.
+ while (__sym_space_end != __sym.end() && __ct.is(ctype_base::space, *__sym_space_end))
+ ++__sym_space_end;
+ const size_t __num_spaces = __sym_space_end - __sym.begin();
+ if (__num_spaces > __spaces.size() ||
+ !std::equal(__spaces.end() - __num_spaces, __spaces.end(), __sym.begin())) {
+ // No match. Put __sym_space_end back at the
+ // beginning of __sym, which will prevent a
+ // match in the next loop.
+ __sym_space_end = __sym.begin();
+ }
+ }
+ typename string_type::const_iterator __sym_curr_char = __sym_space_end;
+ while (__sym_curr_char != __sym.end() && __b != __e && *__b == *__sym_curr_char) {
+ ++__b;
+ ++__sym_curr_char;
+ }
+ if (__sb && __sym_curr_char != __sym.end()) {
+ __err |= ios_base::failbit;
+ return false;
+ }
+ }
+ } break;
+ case money_base::value: {
+ unsigned __ng = 0;
+ for (; __b != __e; ++__b) {
+ char_type __c = *__b;
+ if (__ct.is(ctype_base::digit, __c)) {
+ if (__wn == __we)
+ std::__double_or_nothing(__wb, __wn, __we);
+ *__wn++ = __c;
+ ++__ng;
+ } else if (__grp.size() > 0 && __ng > 0 && __c == __ts) {
+ if (__gn == __ge)
+ std::__double_or_nothing(__gb, __gn, __ge);
+ *__gn++ = __ng;
+ __ng = 0;
+ } else
+ break;
+ }
+ if (__gb.get() != __gn && __ng > 0) {
+ if (__gn == __ge)
+ std::__double_or_nothing(__gb, __gn, __ge);
+ *__gn++ = __ng;
+ }
+ if (__fd > 0) {
+ if (__b == __e || *__b != __dp) {
+ __err |= ios_base::failbit;
+ return false;
+ }
+ for (++__b; __fd > 0; --__fd, ++__b) {
+ if (__b == __e || !__ct.is(ctype_base::digit, *__b)) {
+ __err |= ios_base::failbit;
+ return false;
+ }
+ if (__wn == __we)
+ std::__double_or_nothing(__wb, __wn, __we);
+ *__wn++ = *__b;
+ }
+ }
+ if (__wn == __wb.get()) {
+ __err |= ios_base::failbit;
+ return false;
+ }
+ } break;
+ }
+ }
+ if (__trailing_sign) {
+ for (unsigned __i = 1; __i < __trailing_sign->size(); ++__i, ++__b) {
+ if (__b == __e || *__b != (*__trailing_sign)[__i]) {
+ __err |= ios_base::failbit;
+ return false;
+ }
+ }
+ }
+ if (__gb.get() != __gn) {
+ ios_base::iostate __et = ios_base::goodbit;
+ __check_grouping(__grp, __gb.get(), __gn, __et);
+ if (__et) {
+ __err |= ios_base::failbit;
+ return false;
+ }
+ }
+ return true;
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator money_get<_CharT, _InputIterator>::do_get(
+ iter_type __b, iter_type __e, bool __intl, ios_base& __iob, ios_base::iostate& __err, long double& __v) const {
+ const int __bz = 100;
+ char_type __wbuf[__bz];
+ unique_ptr<char_type, void (*)(void*)> __wb(__wbuf, __do_nothing);
+ char_type* __wn;
+ char_type* __we = __wbuf + __bz;
+ locale __loc = __iob.getloc();
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__loc);
+ bool __neg = false;
+ if (__do_get(__b, __e, __intl, __loc, __iob.flags(), __err, __neg, __ct, __wb, __wn, __we)) {
+ const char __src[] = "0123456789";
+ char_type __atoms[sizeof(__src) - 1];
+ __ct.widen(__src, __src + (sizeof(__src) - 1), __atoms);
+ char __nbuf[__bz];
+ char* __nc = __nbuf;
+ unique_ptr<char, void (*)(void*)> __h(nullptr, free);
+ if (__wn - __wb.get() > __bz - 2) {
+ __h.reset((char*)malloc(static_cast<size_t>(__wn - __wb.get() + 2)));
+ if (__h.get() == nullptr)
+ __throw_bad_alloc();
+ __nc = __h.get();
+ }
+ if (__neg)
+ *__nc++ = '-';
+ for (const char_type* __w = __wb.get(); __w < __wn; ++__w, ++__nc)
+ *__nc = __src[std::find(__atoms, std::end(__atoms), *__w) - __atoms];
+ *__nc = char();
+ if (sscanf(__nbuf, "%Lf", &__v) != 1)
+ __throw_runtime_error("money_get error");
+ }
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ return __b;
+}
+
+template <class _CharT, class _InputIterator>
+_InputIterator money_get<_CharT, _InputIterator>::do_get(
+ iter_type __b, iter_type __e, bool __intl, ios_base& __iob, ios_base::iostate& __err, string_type& __v) const {
+ const int __bz = 100;
+ char_type __wbuf[__bz];
+ unique_ptr<char_type, void (*)(void*)> __wb(__wbuf, __do_nothing);
+ char_type* __wn;
+ char_type* __we = __wbuf + __bz;
+ locale __loc = __iob.getloc();
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__loc);
+ bool __neg = false;
+ if (__do_get(__b, __e, __intl, __loc, __iob.flags(), __err, __neg, __ct, __wb, __wn, __we)) {
+ __v.clear();
+ if (__neg)
+ __v.push_back(__ct.widen('-'));
+ char_type __z = __ct.widen('0');
+ char_type* __w;
+ for (__w = __wb.get(); __w < __wn - 1; ++__w)
+ if (*__w != __z)
+ break;
+ __v.append(__w, __wn);
+ }
+ if (__b == __e)
+ __err |= ios_base::eofbit;
+ return __b;
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS money_get<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS money_get<wchar_t>;
+# endif
+
+// money_put
+
+template <class _CharT>
+class __money_put {
+protected:
+ typedef _CharT char_type;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI __money_put() {}
+
+ static void __gather_info(
+ bool __intl,
+ bool __neg,
+ const locale& __loc,
+ money_base::pattern& __pat,
+ char_type& __dp,
+ char_type& __ts,
+ string& __grp,
+ string_type& __sym,
+ string_type& __sn,
+ int& __fd);
+ static void __format(
+ char_type* __mb,
+ char_type*& __mi,
+ char_type*& __me,
+ ios_base::fmtflags __flags,
+ const char_type* __db,
+ const char_type* __de,
+ const ctype<char_type>& __ct,
+ bool __neg,
+ const money_base::pattern& __pat,
+ char_type __dp,
+ char_type __ts,
+ const string& __grp,
+ const string_type& __sym,
+ const string_type& __sn,
+ int __fd);
+};
+
+template <class _CharT>
+void __money_put<_CharT>::__gather_info(
+ bool __intl,
+ bool __neg,
+ const locale& __loc,
+ money_base::pattern& __pat,
+ char_type& __dp,
+ char_type& __ts,
+ string& __grp,
+ string_type& __sym,
+ string_type& __sn,
+ int& __fd) {
+ if (__intl) {
+ const moneypunct<char_type, true>& __mp = std::use_facet<moneypunct<char_type, true> >(__loc);
+ if (__neg) {
+ __pat = __mp.neg_format();
+ __sn = __mp.negative_sign();
+ } else {
+ __pat = __mp.pos_format();
+ __sn = __mp.positive_sign();
+ }
+ __dp = __mp.decimal_point();
+ __ts = __mp.thousands_sep();
+ __grp = __mp.grouping();
+ __sym = __mp.curr_symbol();
+ __fd = __mp.frac_digits();
+ } else {
+ const moneypunct<char_type, false>& __mp = std::use_facet<moneypunct<char_type, false> >(__loc);
+ if (__neg) {
+ __pat = __mp.neg_format();
+ __sn = __mp.negative_sign();
+ } else {
+ __pat = __mp.pos_format();
+ __sn = __mp.positive_sign();
+ }
+ __dp = __mp.decimal_point();
+ __ts = __mp.thousands_sep();
+ __grp = __mp.grouping();
+ __sym = __mp.curr_symbol();
+ __fd = __mp.frac_digits();
+ }
+}
+
+template <class _CharT>
+void __money_put<_CharT>::__format(
+ char_type* __mb,
+ char_type*& __mi,
+ char_type*& __me,
+ ios_base::fmtflags __flags,
+ const char_type* __db,
+ const char_type* __de,
+ const ctype<char_type>& __ct,
+ bool __neg,
+ const money_base::pattern& __pat,
+ char_type __dp,
+ char_type __ts,
+ const string& __grp,
+ const string_type& __sym,
+ const string_type& __sn,
+ int __fd) {
+ __me = __mb;
+ for (char __p : __pat.field) {
+ switch (__p) {
+ case money_base::none:
+ __mi = __me;
+ break;
+ case money_base::space:
+ __mi = __me;
+ *__me++ = __ct.widen(' ');
+ break;
+ case money_base::sign:
+ if (!__sn.empty())
+ *__me++ = __sn[0];
+ break;
+ case money_base::symbol:
+ if (!__sym.empty() && (__flags & ios_base::showbase))
+ __me = std::copy(__sym.begin(), __sym.end(), __me);
+ break;
+ case money_base::value: {
+ // remember start of value so we can reverse it
+ char_type* __t = __me;
+ // find beginning of digits
+ if (__neg)
+ ++__db;
+ // find end of digits
+ const char_type* __d;
+ for (__d = __db; __d < __de; ++__d)
+ if (!__ct.is(ctype_base::digit, *__d))
+ break;
+ // print fractional part
+ if (__fd > 0) {
+ int __f;
+ for (__f = __fd; __d > __db && __f > 0; --__f)
+ *__me++ = *--__d;
+ char_type __z = __f > 0 ? __ct.widen('0') : char_type();
+ for (; __f > 0; --__f)
+ *__me++ = __z;
+ *__me++ = __dp;
+ }
+ // print units part
+ if (__d == __db) {
+ *__me++ = __ct.widen('0');
+ } else {
+ unsigned __ng = 0;
+ unsigned __ig = 0;
+ unsigned __gl = __grp.empty() ? numeric_limits<unsigned>::max() : static_cast<unsigned>(__grp[__ig]);
+ while (__d != __db) {
+ if (__ng == __gl) {
+ *__me++ = __ts;
+ __ng = 0;
+ if (++__ig < __grp.size())
+ __gl = __grp[__ig] == numeric_limits<char>::max()
+ ? numeric_limits<unsigned>::max()
+ : static_cast<unsigned>(__grp[__ig]);
+ }
+ *__me++ = *--__d;
+ ++__ng;
+ }
+ }
+ // reverse it
+ std::reverse(__t, __me);
+ } break;
+ }
+ }
+ // print rest of sign, if any
+ if (__sn.size() > 1)
+ __me = std::copy(__sn.begin() + 1, __sn.end(), __me);
+ // set alignment
+ if ((__flags & ios_base::adjustfield) == ios_base::left)
+ __mi = __me;
+ else if ((__flags & ios_base::adjustfield) != ios_base::internal)
+ __mi = __mb;
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __money_put<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __money_put<wchar_t>;
+# endif
+
+template <class _CharT, class _OutputIterator = ostreambuf_iterator<_CharT> >
+class _LIBCPP_TEMPLATE_VIS money_put : public locale::facet, private __money_put<_CharT> {
+public:
+ typedef _CharT char_type;
+ typedef _OutputIterator iter_type;
+ typedef basic_string<char_type> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit money_put(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ put(iter_type __s, bool __intl, ios_base& __iob, char_type __fl, long double __units) const {
+ return do_put(__s, __intl, __iob, __fl, __units);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iter_type
+ put(iter_type __s, bool __intl, ios_base& __iob, char_type __fl, const string_type& __digits) const {
+ return do_put(__s, __intl, __iob, __fl, __digits);
+ }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~money_put() override {}
+
+ virtual iter_type do_put(iter_type __s, bool __intl, ios_base& __iob, char_type __fl, long double __units) const;
+ virtual iter_type
+ do_put(iter_type __s, bool __intl, ios_base& __iob, char_type __fl, const string_type& __digits) const;
+};
+
+template <class _CharT, class _OutputIterator>
+locale::id money_put<_CharT, _OutputIterator>::id;
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator money_put<_CharT, _OutputIterator>::do_put(
+ iter_type __s, bool __intl, ios_base& __iob, char_type __fl, long double __units) const {
+ // convert to char
+ const size_t __bs = 100;
+ char __buf[__bs];
+ char* __bb = __buf;
+ char_type __digits[__bs];
+ char_type* __db = __digits;
+ int __n = snprintf(__bb, __bs, "%.0Lf", __units);
+ unique_ptr<char, void (*)(void*)> __hn(nullptr, free);
+ unique_ptr<char_type, void (*)(void*)> __hd(0, free);
+ // secure memory for digit storage
+ if (static_cast<size_t>(__n) > __bs - 1) {
+ __n = __libcpp_asprintf_l(&__bb, _LIBCPP_GET_C_LOCALE, "%.0Lf", __units);
+ if (__n == -1)
+ __throw_bad_alloc();
+ __hn.reset(__bb);
+ __hd.reset((char_type*)malloc(static_cast<size_t>(__n) * sizeof(char_type)));
+ if (__hd == nullptr)
+ __throw_bad_alloc();
+ __db = __hd.get();
+ }
+ // gather info
+ locale __loc = __iob.getloc();
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__loc);
+ __ct.widen(__bb, __bb + __n, __db);
+ bool __neg = __n > 0 && __bb[0] == '-';
+ money_base::pattern __pat;
+ char_type __dp;
+ char_type __ts;
+ string __grp;
+ string_type __sym;
+ string_type __sn;
+ int __fd;
+ this->__gather_info(__intl, __neg, __loc, __pat, __dp, __ts, __grp, __sym, __sn, __fd);
+ // secure memory for formatting
+ char_type __mbuf[__bs];
+ char_type* __mb = __mbuf;
+ unique_ptr<char_type, void (*)(void*)> __hw(0, free);
+ size_t __exn = __n > __fd ? (static_cast<size_t>(__n) - static_cast<size_t>(__fd)) * 2 + __sn.size() + __sym.size() +
+ static_cast<size_t>(__fd) + 1
+ : __sn.size() + __sym.size() + static_cast<size_t>(__fd) + 2;
+ if (__exn > __bs) {
+ __hw.reset((char_type*)malloc(__exn * sizeof(char_type)));
+ __mb = __hw.get();
+ if (__mb == 0)
+ __throw_bad_alloc();
+ }
+ // format
+ char_type* __mi;
+ char_type* __me;
+ this->__format(
+ __mb, __mi, __me, __iob.flags(), __db, __db + __n, __ct, __neg, __pat, __dp, __ts, __grp, __sym, __sn, __fd);
+ return std::__pad_and_output(__s, __mb, __mi, __me, __iob, __fl);
+}
+
+template <class _CharT, class _OutputIterator>
+_OutputIterator money_put<_CharT, _OutputIterator>::do_put(
+ iter_type __s, bool __intl, ios_base& __iob, char_type __fl, const string_type& __digits) const {
+ // gather info
+ locale __loc = __iob.getloc();
+ const ctype<char_type>& __ct = std::use_facet<ctype<char_type> >(__loc);
+ bool __neg = __digits.size() > 0 && __digits[0] == __ct.widen('-');
+ money_base::pattern __pat;
+ char_type __dp;
+ char_type __ts;
+ string __grp;
+ string_type __sym;
+ string_type __sn;
+ int __fd;
+ this->__gather_info(__intl, __neg, __loc, __pat, __dp, __ts, __grp, __sym, __sn, __fd);
+ // secure memory for formatting
+ char_type __mbuf[100];
+ char_type* __mb = __mbuf;
+ unique_ptr<char_type, void (*)(void*)> __h(0, free);
+ size_t __exn =
+ static_cast<int>(__digits.size()) > __fd
+ ? (__digits.size() - static_cast<size_t>(__fd)) * 2 + __sn.size() + __sym.size() + static_cast<size_t>(__fd) +
+ 1
+ : __sn.size() + __sym.size() + static_cast<size_t>(__fd) + 2;
+ if (__exn > 100) {
+ __h.reset((char_type*)malloc(__exn * sizeof(char_type)));
+ __mb = __h.get();
+ if (__mb == 0)
+ __throw_bad_alloc();
+ }
+ // format
+ char_type* __mi;
+ char_type* __me;
+ this->__format(
+ __mb,
+ __mi,
+ __me,
+ __iob.flags(),
+ __digits.data(),
+ __digits.data() + __digits.size(),
+ __ct,
+ __neg,
+ __pat,
+ __dp,
+ __ts,
+ __grp,
+ __sym,
+ __sn,
+ __fd);
+ return std::__pad_and_output(__s, __mb, __mi, __me, __iob, __fl);
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS money_put<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS money_put<wchar_t>;
+# endif
+
+// messages
+
+class _LIBCPP_EXPORTED_FROM_ABI messages_base {
+public:
+ typedef intptr_t catalog;
+
+ _LIBCPP_HIDE_FROM_ABI messages_base() {}
+};
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS messages : public locale::facet, public messages_base {
+public:
+ typedef _CharT char_type;
+ typedef basic_string<_CharT> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit messages(size_t __refs = 0) : locale::facet(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI catalog open(const basic_string<char>& __nm, const locale& __loc) const {
+ return do_open(__nm, __loc);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI string_type get(catalog __c, int __set, int __msgid, const string_type& __dflt) const {
+ return do_get(__c, __set, __msgid, __dflt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void close(catalog __c) const { do_close(__c); }
+
+ static locale::id id;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~messages() override {}
+
+ virtual catalog do_open(const basic_string<char>&, const locale&) const;
+ virtual string_type do_get(catalog, int __set, int __msgid, const string_type& __dflt) const;
+ virtual void do_close(catalog) const;
+};
+
+template <class _CharT>
+locale::id messages<_CharT>::id;
+
+template <class _CharT>
+typename messages<_CharT>::catalog messages<_CharT>::do_open(const basic_string<char>& __nm, const locale&) const {
+# ifdef _LIBCPP_HAS_CATOPEN
+ return (catalog)catopen(__nm.c_str(), NL_CAT_LOCALE);
+# else // !_LIBCPP_HAS_CATOPEN
+ (void)__nm;
+ return -1;
+# endif // _LIBCPP_HAS_CATOPEN
+}
+
+template <class _CharT>
+typename messages<_CharT>::string_type
+messages<_CharT>::do_get(catalog __c, int __set, int __msgid, const string_type& __dflt) const {
+# ifdef _LIBCPP_HAS_CATOPEN
+ string __ndflt;
+ __narrow_to_utf8<sizeof(char_type) * __CHAR_BIT__>()(
+ std::back_inserter(__ndflt), __dflt.c_str(), __dflt.c_str() + __dflt.size());
+ nl_catd __cat = (nl_catd)__c;
+ static_assert(sizeof(catalog) >= sizeof(nl_catd), "Unexpected nl_catd type");
+ char* __n = catgets(__cat, __set, __msgid, __ndflt.c_str());
+ string_type __w;
+ __widen_from_utf8<sizeof(char_type) * __CHAR_BIT__>()(std::back_inserter(__w), __n, __n + std::strlen(__n));
+ return __w;
+# else // !_LIBCPP_HAS_CATOPEN
+ (void)__c;
+ (void)__set;
+ (void)__msgid;
+ return __dflt;
+# endif // _LIBCPP_HAS_CATOPEN
+}
+
+template <class _CharT>
+void messages<_CharT>::do_close(catalog __c) const {
+# ifdef _LIBCPP_HAS_CATOPEN
+ catclose((nl_catd)__c);
+# else // !_LIBCPP_HAS_CATOPEN
+ (void)__c;
+# endif // _LIBCPP_HAS_CATOPEN
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS messages<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS messages<wchar_t>;
+# endif
+
+template <class _CharT>
+class _LIBCPP_TEMPLATE_VIS messages_byname : public messages<_CharT> {
+public:
+ typedef messages_base::catalog catalog;
+ typedef basic_string<_CharT> string_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit messages_byname(const char*, size_t __refs = 0) : messages<_CharT>(__refs) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit messages_byname(const string&, size_t __refs = 0) : messages<_CharT>(__refs) {}
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~messages_byname() override {}
+};
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS messages_byname<char>;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS messages_byname<wchar_t>;
+# endif
+
+# if _LIBCPP_STD_VER < 26 || defined(_LIBCPP_ENABLE_CXX26_REMOVED_WSTRING_CONVERT)
+
+template <class _Codecvt,
+ class _Elem = wchar_t,
+ class _WideAlloc = allocator<_Elem>,
+ class _ByteAlloc = allocator<char> >
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 wstring_convert {
+public:
+ typedef basic_string<char, char_traits<char>, _ByteAlloc> byte_string;
+ typedef basic_string<_Elem, char_traits<_Elem>, _WideAlloc> wide_string;
+ typedef typename _Codecvt::state_type state_type;
+ typedef typename wide_string::traits_type::int_type int_type;
+
+private:
+ byte_string __byte_err_string_;
+ wide_string __wide_err_string_;
+ _Codecvt* __cvtptr_;
+ state_type __cvtstate_;
+ size_t __cvtcount_;
+
+public:
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI wstring_convert() : wstring_convert(new _Codecvt) {}
+ _LIBCPP_HIDE_FROM_ABI explicit wstring_convert(_Codecvt* __pcvt);
+# else
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_EXPLICIT_SINCE_CXX14 wstring_convert(_Codecvt* __pcvt = new _Codecvt);
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI wstring_convert(_Codecvt* __pcvt, state_type __state);
+ _LIBCPP_EXPLICIT_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+ wstring_convert(const byte_string& __byte_err, const wide_string& __wide_err = wide_string());
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI wstring_convert(wstring_convert&& __wc);
+# endif
+ _LIBCPP_HIDE_FROM_ABI ~wstring_convert();
+
+ wstring_convert(const wstring_convert& __wc) = delete;
+ wstring_convert& operator=(const wstring_convert& __wc) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI wide_string from_bytes(char __byte) { return from_bytes(&__byte, &__byte + 1); }
+ _LIBCPP_HIDE_FROM_ABI wide_string from_bytes(const char* __ptr) {
+ return from_bytes(__ptr, __ptr + char_traits<char>::length(__ptr));
+ }
+ _LIBCPP_HIDE_FROM_ABI wide_string from_bytes(const byte_string& __str) {
+ return from_bytes(__str.data(), __str.data() + __str.size());
+ }
+ _LIBCPP_HIDE_FROM_ABI wide_string from_bytes(const char* __first, const char* __last);
+
+ _LIBCPP_HIDE_FROM_ABI byte_string to_bytes(_Elem __wchar) { return to_bytes(&__wchar, &__wchar + 1); }
+ _LIBCPP_HIDE_FROM_ABI byte_string to_bytes(const _Elem* __wptr) {
+ return to_bytes(__wptr, __wptr + char_traits<_Elem>::length(__wptr));
+ }
+ _LIBCPP_HIDE_FROM_ABI byte_string to_bytes(const wide_string& __wstr) {
+ return to_bytes(__wstr.data(), __wstr.data() + __wstr.size());
+ }
+ _LIBCPP_HIDE_FROM_ABI byte_string to_bytes(const _Elem* __first, const _Elem* __last);
+
+ _LIBCPP_HIDE_FROM_ABI size_t converted() const _NOEXCEPT { return __cvtcount_; }
+ _LIBCPP_HIDE_FROM_ABI state_type state() const { return __cvtstate_; }
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Codecvt, class _Elem, class _WideAlloc, class _ByteAlloc>
+inline wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::wstring_convert(_Codecvt* __pcvt)
+ : __cvtptr_(__pcvt), __cvtstate_(), __cvtcount_(0) {}
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+template <class _Codecvt, class _Elem, class _WideAlloc, class _ByteAlloc>
+inline wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::wstring_convert(_Codecvt* __pcvt, state_type __state)
+ : __cvtptr_(__pcvt), __cvtstate_(__state), __cvtcount_(0) {}
+
+template <class _Codecvt, class _Elem, class _WideAlloc, class _ByteAlloc>
+wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::wstring_convert(
+ const byte_string& __byte_err, const wide_string& __wide_err)
+ : __byte_err_string_(__byte_err), __wide_err_string_(__wide_err), __cvtstate_(), __cvtcount_(0) {
+ __cvtptr_ = new _Codecvt;
+}
+
+# ifndef _LIBCPP_CXX03_LANG
+
+template <class _Codecvt, class _Elem, class _WideAlloc, class _ByteAlloc>
+inline wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::wstring_convert(wstring_convert&& __wc)
+ : __byte_err_string_(std::move(__wc.__byte_err_string_)),
+ __wide_err_string_(std::move(__wc.__wide_err_string_)),
+ __cvtptr_(__wc.__cvtptr_),
+ __cvtstate_(__wc.__cvtstate_),
+ __cvtcount_(__wc.__cvtcount_) {
+ __wc.__cvtptr_ = nullptr;
+}
+
+# endif // _LIBCPP_CXX03_LANG
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Codecvt, class _Elem, class _WideAlloc, class _ByteAlloc>
+wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::~wstring_convert() {
+ delete __cvtptr_;
+}
+
+template <class _Codecvt, class _Elem, class _WideAlloc, class _ByteAlloc>
+typename wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::wide_string
+wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::from_bytes(const char* __frm, const char* __frm_end) {
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ __cvtcount_ = 0;
+ if (__cvtptr_ != nullptr) {
+ wide_string __ws(2 * (__frm_end - __frm), _Elem());
+ if (__frm != __frm_end)
+ __ws.resize(__ws.capacity());
+ codecvt_base::result __r = codecvt_base::ok;
+ state_type __st = __cvtstate_;
+ if (__frm != __frm_end) {
+ _Elem* __to = &__ws[0];
+ _Elem* __to_end = __to + __ws.size();
+ const char* __frm_nxt;
+ do {
+ _Elem* __to_nxt;
+ __r = __cvtptr_->in(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ __cvtcount_ += __frm_nxt - __frm;
+ if (__frm_nxt == __frm) {
+ __r = codecvt_base::error;
+ } else if (__r == codecvt_base::noconv) {
+ __ws.resize(__to - &__ws[0]);
+ // This only gets executed if _Elem is char
+ __ws.append((const _Elem*)__frm, (const _Elem*)__frm_end);
+ __frm = __frm_nxt;
+ __r = codecvt_base::ok;
+ } else if (__r == codecvt_base::ok) {
+ __ws.resize(__to_nxt - &__ws[0]);
+ __frm = __frm_nxt;
+ } else if (__r == codecvt_base::partial) {
+ ptrdiff_t __s = __to_nxt - &__ws[0];
+ __ws.resize(2 * __s);
+ __to = &__ws[0] + __s;
+ __to_end = &__ws[0] + __ws.size();
+ __frm = __frm_nxt;
+ }
+ } while (__r == codecvt_base::partial && __frm_nxt < __frm_end);
+ }
+ if (__r == codecvt_base::ok)
+ return __ws;
+ }
+
+ if (__wide_err_string_.empty())
+ __throw_range_error("wstring_convert: from_bytes error");
+
+ return __wide_err_string_;
+}
+
+template <class _Codecvt, class _Elem, class _WideAlloc, class _ByteAlloc>
+typename wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::byte_string
+wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::to_bytes(const _Elem* __frm, const _Elem* __frm_end) {
+ __cvtcount_ = 0;
+ if (__cvtptr_ != nullptr) {
+ byte_string __bs(2 * (__frm_end - __frm), char());
+ if (__frm != __frm_end)
+ __bs.resize(__bs.capacity());
+ codecvt_base::result __r = codecvt_base::ok;
+ state_type __st = __cvtstate_;
+ if (__frm != __frm_end) {
+ char* __to = &__bs[0];
+ char* __to_end = __to + __bs.size();
+ const _Elem* __frm_nxt;
+ do {
+ char* __to_nxt;
+ __r = __cvtptr_->out(__st, __frm, __frm_end, __frm_nxt, __to, __to_end, __to_nxt);
+ __cvtcount_ += __frm_nxt - __frm;
+ if (__frm_nxt == __frm) {
+ __r = codecvt_base::error;
+ } else if (__r == codecvt_base::noconv) {
+ __bs.resize(__to - &__bs[0]);
+ // This only gets executed if _Elem is char
+ __bs.append((const char*)__frm, (const char*)__frm_end);
+ __frm = __frm_nxt;
+ __r = codecvt_base::ok;
+ } else if (__r == codecvt_base::ok) {
+ __bs.resize(__to_nxt - &__bs[0]);
+ __frm = __frm_nxt;
+ } else if (__r == codecvt_base::partial) {
+ ptrdiff_t __s = __to_nxt - &__bs[0];
+ __bs.resize(2 * __s);
+ __to = &__bs[0] + __s;
+ __to_end = &__bs[0] + __bs.size();
+ __frm = __frm_nxt;
+ }
+ } while (__r == codecvt_base::partial && __frm_nxt < __frm_end);
+ }
+ if (__r == codecvt_base::ok) {
+ size_t __s = __bs.size();
+ __bs.resize(__bs.capacity());
+ char* __to = &__bs[0] + __s;
+ char* __to_end = __to + __bs.size();
+ do {
+ char* __to_nxt;
+ __r = __cvtptr_->unshift(__st, __to, __to_end, __to_nxt);
+ if (__r == codecvt_base::noconv) {
+ __bs.resize(__to - &__bs[0]);
+ __r = codecvt_base::ok;
+ } else if (__r == codecvt_base::ok) {
+ __bs.resize(__to_nxt - &__bs[0]);
+ } else if (__r == codecvt_base::partial) {
+ ptrdiff_t __sp = __to_nxt - &__bs[0];
+ __bs.resize(2 * __sp);
+ __to = &__bs[0] + __sp;
+ __to_end = &__bs[0] + __bs.size();
+ }
+ } while (__r == codecvt_base::partial);
+ if (__r == codecvt_base::ok)
+ return __bs;
+ }
+ }
+
+ if (__byte_err_string_.empty())
+ __throw_range_error("wstring_convert: to_bytes error");
+
+ return __byte_err_string_;
+}
+
+template <class _Codecvt, class _Elem = wchar_t, class _Tr = char_traits<_Elem> >
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 wbuffer_convert : public basic_streambuf<_Elem, _Tr> {
+public:
+ // types:
+ typedef _Elem char_type;
+ typedef _Tr traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef typename _Codecvt::state_type state_type;
+
+private:
+ char* __extbuf_;
+ const char* __extbufnext_;
+ const char* __extbufend_;
+ char __extbuf_min_[8];
+ size_t __ebs_;
+ char_type* __intbuf_;
+ size_t __ibs_;
+ streambuf* __bufptr_;
+ _Codecvt* __cv_;
+ state_type __st_;
+ ios_base::openmode __cm_;
+ bool __owns_eb_;
+ bool __owns_ib_;
+ bool __always_noconv_;
+
+public:
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI wbuffer_convert() : wbuffer_convert(nullptr) {}
+ explicit _LIBCPP_HIDE_FROM_ABI
+ wbuffer_convert(streambuf* __bytebuf, _Codecvt* __pcvt = new _Codecvt, state_type __state = state_type());
+# else
+ _LIBCPP_EXPLICIT_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
+ wbuffer_convert(streambuf* __bytebuf = nullptr, _Codecvt* __pcvt = new _Codecvt, state_type __state = state_type());
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI ~wbuffer_convert();
+
+ _LIBCPP_HIDE_FROM_ABI streambuf* rdbuf() const { return __bufptr_; }
+ _LIBCPP_HIDE_FROM_ABI streambuf* rdbuf(streambuf* __bytebuf) {
+ streambuf* __r = __bufptr_;
+ __bufptr_ = __bytebuf;
+ return __r;
+ }
+
+ wbuffer_convert(const wbuffer_convert&) = delete;
+ wbuffer_convert& operator=(const wbuffer_convert&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI state_type state() const { return __st_; }
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual int_type underflow();
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual int_type pbackfail(int_type __c = traits_type::eof());
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual int_type overflow(int_type __c = traits_type::eof());
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual basic_streambuf<char_type, traits_type>* setbuf(char_type* __s, streamsize __n);
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual pos_type
+ seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __wch = ios_base::in | ios_base::out);
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual pos_type
+ seekpos(pos_type __sp, ios_base::openmode __wch = ios_base::in | ios_base::out);
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual int sync();
+
+private:
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL bool __read_mode();
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL void __write_mode();
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL wbuffer_convert* __close();
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Codecvt, class _Elem, class _Tr>
+wbuffer_convert<_Codecvt, _Elem, _Tr>::wbuffer_convert(streambuf* __bytebuf, _Codecvt* __pcvt, state_type __state)
+ : __extbuf_(nullptr),
+ __extbufnext_(nullptr),
+ __extbufend_(nullptr),
+ __ebs_(0),
+ __intbuf_(0),
+ __ibs_(0),
+ __bufptr_(__bytebuf),
+ __cv_(__pcvt),
+ __st_(__state),
+ __cm_(0),
+ __owns_eb_(false),
+ __owns_ib_(false),
+ __always_noconv_(__cv_ ? __cv_->always_noconv() : false) {
+ setbuf(0, 4096);
+}
+
+template <class _Codecvt, class _Elem, class _Tr>
+wbuffer_convert<_Codecvt, _Elem, _Tr>::~wbuffer_convert() {
+ __close();
+ delete __cv_;
+ if (__owns_eb_)
+ delete[] __extbuf_;
+ if (__owns_ib_)
+ delete[] __intbuf_;
+}
+
+template <class _Codecvt, class _Elem, class _Tr>
+typename wbuffer_convert<_Codecvt, _Elem, _Tr>::int_type wbuffer_convert<_Codecvt, _Elem, _Tr>::underflow() {
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ if (__cv_ == 0 || __bufptr_ == nullptr)
+ return traits_type::eof();
+ bool __initial = __read_mode();
+ char_type __1buf;
+ if (this->gptr() == 0)
+ this->setg(&__1buf, &__1buf + 1, &__1buf + 1);
+ const size_t __unget_sz = __initial ? 0 : std::min<size_t>((this->egptr() - this->eback()) / 2, 4);
+ int_type __c = traits_type::eof();
+ if (this->gptr() == this->egptr()) {
+ std::memmove(this->eback(), this->egptr() - __unget_sz, __unget_sz * sizeof(char_type));
+ if (__always_noconv_) {
+ streamsize __nmemb = static_cast<streamsize>(this->egptr() - this->eback() - __unget_sz);
+ __nmemb = __bufptr_->sgetn((char*)this->eback() + __unget_sz, __nmemb);
+ if (__nmemb != 0) {
+ this->setg(this->eback(), this->eback() + __unget_sz, this->eback() + __unget_sz + __nmemb);
+ __c = *this->gptr();
+ }
+ } else {
+ if (__extbufend_ != __extbufnext_) {
+ _LIBCPP_ASSERT_NON_NULL(__extbufnext_ != nullptr, "underflow moving from nullptr");
+ _LIBCPP_ASSERT_NON_NULL(__extbuf_ != nullptr, "underflow moving into nullptr");
+ std::memmove(__extbuf_, __extbufnext_, __extbufend_ - __extbufnext_);
+ }
+ __extbufnext_ = __extbuf_ + (__extbufend_ - __extbufnext_);
+ __extbufend_ = __extbuf_ + (__extbuf_ == __extbuf_min_ ? sizeof(__extbuf_min_) : __ebs_);
+ streamsize __nmemb = std::min(static_cast<streamsize>(this->egptr() - this->eback() - __unget_sz),
+ static_cast<streamsize>(__extbufend_ - __extbufnext_));
+ codecvt_base::result __r;
+ // FIXME: Do we ever need to restore the state here?
+ // state_type __svs = __st_;
+ streamsize __nr = __bufptr_->sgetn(const_cast<char*>(__extbufnext_), __nmemb);
+ if (__nr != 0) {
+ __extbufend_ = __extbufnext_ + __nr;
+ char_type* __inext;
+ __r = __cv_->in(
+ __st_, __extbuf_, __extbufend_, __extbufnext_, this->eback() + __unget_sz, this->egptr(), __inext);
+ if (__r == codecvt_base::noconv) {
+ this->setg((char_type*)__extbuf_, (char_type*)__extbuf_, (char_type*)const_cast<char*>(__extbufend_));
+ __c = *this->gptr();
+ } else if (__inext != this->eback() + __unget_sz) {
+ this->setg(this->eback(), this->eback() + __unget_sz, __inext);
+ __c = *this->gptr();
+ }
+ }
+ }
+ } else
+ __c = *this->gptr();
+ if (this->eback() == &__1buf)
+ this->setg(0, 0, 0);
+ return __c;
+}
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Codecvt, class _Elem, class _Tr>
+typename wbuffer_convert<_Codecvt, _Elem, _Tr>::int_type
+wbuffer_convert<_Codecvt, _Elem, _Tr>::pbackfail(int_type __c) {
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ if (__cv_ != 0 && __bufptr_ && this->eback() < this->gptr()) {
+ if (traits_type::eq_int_type(__c, traits_type::eof())) {
+ this->gbump(-1);
+ return traits_type::not_eof(__c);
+ }
+ if (traits_type::eq(traits_type::to_char_type(__c), this->gptr()[-1])) {
+ this->gbump(-1);
+ *this->gptr() = traits_type::to_char_type(__c);
+ return __c;
+ }
+ }
+ return traits_type::eof();
+}
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Codecvt, class _Elem, class _Tr>
+typename wbuffer_convert<_Codecvt, _Elem, _Tr>::int_type wbuffer_convert<_Codecvt, _Elem, _Tr>::overflow(int_type __c) {
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ if (__cv_ == 0 || !__bufptr_)
+ return traits_type::eof();
+ __write_mode();
+ char_type __1buf;
+ char_type* __pb_save = this->pbase();
+ char_type* __epb_save = this->epptr();
+ if (!traits_type::eq_int_type(__c, traits_type::eof())) {
+ if (this->pptr() == 0)
+ this->setp(&__1buf, &__1buf + 1);
+ *this->pptr() = traits_type::to_char_type(__c);
+ this->pbump(1);
+ }
+ if (this->pptr() != this->pbase()) {
+ if (__always_noconv_) {
+ streamsize __nmemb = static_cast<streamsize>(this->pptr() - this->pbase());
+ if (__bufptr_->sputn((const char*)this->pbase(), __nmemb) != __nmemb)
+ return traits_type::eof();
+ } else {
+ char* __extbe = __extbuf_;
+ codecvt_base::result __r;
+ do {
+ const char_type* __e;
+ __r = __cv_->out(__st_, this->pbase(), this->pptr(), __e, __extbuf_, __extbuf_ + __ebs_, __extbe);
+ if (__e == this->pbase())
+ return traits_type::eof();
+ if (__r == codecvt_base::noconv) {
+ streamsize __nmemb = static_cast<size_t>(this->pptr() - this->pbase());
+ if (__bufptr_->sputn((const char*)this->pbase(), __nmemb) != __nmemb)
+ return traits_type::eof();
+ } else if (__r == codecvt_base::ok || __r == codecvt_base::partial) {
+ streamsize __nmemb = static_cast<size_t>(__extbe - __extbuf_);
+ if (__bufptr_->sputn(__extbuf_, __nmemb) != __nmemb)
+ return traits_type::eof();
+ if (__r == codecvt_base::partial) {
+ this->setp(const_cast<char_type*>(__e), this->pptr());
+ this->__pbump(this->epptr() - this->pbase());
+ }
+ } else
+ return traits_type::eof();
+ } while (__r == codecvt_base::partial);
+ }
+ this->setp(__pb_save, __epb_save);
+ }
+ return traits_type::not_eof(__c);
+}
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Codecvt, class _Elem, class _Tr>
+basic_streambuf<_Elem, _Tr>* wbuffer_convert<_Codecvt, _Elem, _Tr>::setbuf(char_type* __s, streamsize __n) {
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ this->setg(0, 0, 0);
+ this->setp(0, 0);
+ if (__owns_eb_)
+ delete[] __extbuf_;
+ if (__owns_ib_)
+ delete[] __intbuf_;
+ __ebs_ = __n;
+ if (__ebs_ > sizeof(__extbuf_min_)) {
+ if (__always_noconv_ && __s) {
+ __extbuf_ = (char*)__s;
+ __owns_eb_ = false;
+ } else {
+ __extbuf_ = new char[__ebs_];
+ __owns_eb_ = true;
+ }
+ } else {
+ __extbuf_ = __extbuf_min_;
+ __ebs_ = sizeof(__extbuf_min_);
+ __owns_eb_ = false;
+ }
+ if (!__always_noconv_) {
+ __ibs_ = max<streamsize>(__n, sizeof(__extbuf_min_));
+ if (__s && __ibs_ >= sizeof(__extbuf_min_)) {
+ __intbuf_ = __s;
+ __owns_ib_ = false;
+ } else {
+ __intbuf_ = new char_type[__ibs_];
+ __owns_ib_ = true;
+ }
+ } else {
+ __ibs_ = 0;
+ __intbuf_ = 0;
+ __owns_ib_ = false;
+ }
+ return this;
+}
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Codecvt, class _Elem, class _Tr>
+typename wbuffer_convert<_Codecvt, _Elem, _Tr>::pos_type
+wbuffer_convert<_Codecvt, _Elem, _Tr>::seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __om) {
+ int __width = __cv_->encoding();
+ if (__cv_ == 0 || !__bufptr_ || (__width <= 0 && __off != 0) || sync())
+ return pos_type(off_type(-1));
+ // __width > 0 || __off == 0, now check __way
+ if (__way != ios_base::beg && __way != ios_base::cur && __way != ios_base::end)
+ return pos_type(off_type(-1));
+ pos_type __r = __bufptr_->pubseekoff(__width * __off, __way, __om);
+ __r.state(__st_);
+ return __r;
+}
+
+template <class _Codecvt, class _Elem, class _Tr>
+typename wbuffer_convert<_Codecvt, _Elem, _Tr>::pos_type
+wbuffer_convert<_Codecvt, _Elem, _Tr>::seekpos(pos_type __sp, ios_base::openmode __wch) {
+ if (__cv_ == 0 || !__bufptr_ || sync())
+ return pos_type(off_type(-1));
+ if (__bufptr_->pubseekpos(__sp, __wch) == pos_type(off_type(-1)))
+ return pos_type(off_type(-1));
+ return __sp;
+}
+
+template <class _Codecvt, class _Elem, class _Tr>
+int wbuffer_convert<_Codecvt, _Elem, _Tr>::sync() {
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ if (__cv_ == 0 || !__bufptr_)
+ return 0;
+ if (__cm_ & ios_base::out) {
+ if (this->pptr() != this->pbase())
+ if (overflow() == traits_type::eof())
+ return -1;
+ codecvt_base::result __r;
+ do {
+ char* __extbe;
+ __r = __cv_->unshift(__st_, __extbuf_, __extbuf_ + __ebs_, __extbe);
+ streamsize __nmemb = static_cast<streamsize>(__extbe - __extbuf_);
+ if (__bufptr_->sputn(__extbuf_, __nmemb) != __nmemb)
+ return -1;
+ } while (__r == codecvt_base::partial);
+ if (__r == codecvt_base::error)
+ return -1;
+ if (__bufptr_->pubsync())
+ return -1;
+ } else if (__cm_ & ios_base::in) {
+ off_type __c;
+ if (__always_noconv_)
+ __c = this->egptr() - this->gptr();
+ else {
+ int __width = __cv_->encoding();
+ __c = __extbufend_ - __extbufnext_;
+ if (__width > 0)
+ __c += __width * (this->egptr() - this->gptr());
+ else {
+ if (this->gptr() != this->egptr()) {
+ std::reverse(this->gptr(), this->egptr());
+ codecvt_base::result __r;
+ const char_type* __e = this->gptr();
+ char* __extbe;
+ do {
+ __r = __cv_->out(__st_, __e, this->egptr(), __e, __extbuf_, __extbuf_ + __ebs_, __extbe);
+ switch (__r) {
+ case codecvt_base::noconv:
+ __c += this->egptr() - this->gptr();
+ break;
+ case codecvt_base::ok:
+ case codecvt_base::partial:
+ __c += __extbe - __extbuf_;
+ break;
+ default:
+ return -1;
+ }
+ } while (__r == codecvt_base::partial);
+ }
+ }
+ }
+ if (__bufptr_->pubseekoff(-__c, ios_base::cur, __cm_) == pos_type(off_type(-1)))
+ return -1;
+ this->setg(0, 0, 0);
+ __cm_ = 0;
+ }
+ return 0;
+}
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+template <class _Codecvt, class _Elem, class _Tr>
+bool wbuffer_convert<_Codecvt, _Elem, _Tr>::__read_mode() {
+ if (!(__cm_ & ios_base::in)) {
+ this->setp(0, 0);
+ if (__always_noconv_)
+ this->setg((char_type*)__extbuf_, (char_type*)__extbuf_ + __ebs_, (char_type*)__extbuf_ + __ebs_);
+ else
+ this->setg(__intbuf_, __intbuf_ + __ibs_, __intbuf_ + __ibs_);
+ __cm_ = ios_base::in;
+ return true;
+ }
+ return false;
+}
+
+template <class _Codecvt, class _Elem, class _Tr>
+void wbuffer_convert<_Codecvt, _Elem, _Tr>::__write_mode() {
+ if (!(__cm_ & ios_base::out)) {
+ this->setg(0, 0, 0);
+ if (__ebs_ > sizeof(__extbuf_min_)) {
+ if (__always_noconv_)
+ this->setp((char_type*)__extbuf_, (char_type*)__extbuf_ + (__ebs_ - 1));
+ else
+ this->setp(__intbuf_, __intbuf_ + (__ibs_ - 1));
+ } else
+ this->setp(0, 0);
+ __cm_ = ios_base::out;
+ }
+}
+
+template <class _Codecvt, class _Elem, class _Tr>
+wbuffer_convert<_Codecvt, _Elem, _Tr>* wbuffer_convert<_Codecvt, _Elem, _Tr>::__close() {
+ wbuffer_convert* __rt = nullptr;
+ if (__cv_ != nullptr && __bufptr_ != nullptr) {
+ __rt = this;
+ if ((__cm_ & ios_base::out) && sync())
+ __rt = nullptr;
+ }
+ return __rt;
+}
+
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+# endif // _LIBCPP_STD_VER < 26 || defined(_LIBCPP_ENABLE_CXX26_REMOVED_WSTRING_CONVERT)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+// NOLINTEND(libcpp-robust-against-adl)
+
+#endif // !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstdarg>
+# include <iterator>
+# include <mutex>
+# include <stdexcept>
+# include <type_traits>
+# include <typeinfo>
+#endif
+
+#endif // _LIBCPP_LOCALE
diff --git a/libcxx/include/__cxx03/locale.h b/libcxx/include/__cxx03/locale.h
new file mode 100644
index 00000000000000..425bf47d437ac8
--- /dev/null
+++ b/libcxx/include/__cxx03/locale.h
@@ -0,0 +1,46 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_LOCALE_H
+#define _LIBCPP_LOCALE_H
+
+/*
+ locale.h synopsis
+
+Macros:
+
+ LC_ALL
+ LC_COLLATE
+ LC_CTYPE
+ LC_MONETARY
+ LC_NUMERIC
+ LC_TIME
+
+Types:
+
+ lconv
+
+Functions:
+
+ setlocale
+ localeconv
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if __has_include_next(<locale.h>)
+# include_next <locale.h>
+#endif
+
+#endif // _LIBCPP_LOCALE_H
diff --git a/libcxx/include/__cxx03/map b/libcxx/include/__cxx03/map
new file mode 100644
index 00000000000000..02bd17ccb4e8cb
--- /dev/null
+++ b/libcxx/include/__cxx03/map
@@ -0,0 +1,2181 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_MAP
+#define _LIBCPP_MAP
+
+/*
+
+ map synopsis
+
+namespace std
+{
+
+template <class Key, class T, class Compare = less<Key>,
+ class Allocator = allocator<pair<const Key, T>>>
+class map
+{
+public:
+ // types:
+ typedef Key key_type;
+ typedef T mapped_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef Compare key_compare;
+ typedef Allocator allocator_type;
+ typedef typename allocator_type::reference reference;
+ typedef typename allocator_type::const_reference const_reference;
+ typedef typename allocator_type::pointer pointer;
+ typedef typename allocator_type::const_pointer const_pointer;
+ typedef typename allocator_type::size_type size_type;
+ typedef typename allocator_type::difference_type difference_type;
+
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+ typedef unspecified node_type; // C++17
+ typedef INSERT_RETURN_TYPE<iterator, node_type> insert_return_type; // C++17
+
+ class value_compare
+ {
+ friend class map;
+ protected:
+ key_compare comp;
+
+ value_compare(key_compare c);
+ public:
+ typedef bool result_type; // deprecated in C++17, removed in C++20
+ typedef value_type first_argument_type; // deprecated in C++17, removed in C++20
+ typedef value_type second_argument_type; // deprecated in C++17, removed in C++20
+ bool operator()(const value_type& x, const value_type& y) const;
+ };
+
+ // construct/copy/destroy:
+ map()
+ noexcept(
+ is_nothrow_default_constructible<allocator_type>::value &&
+ is_nothrow_default_constructible<key_compare>::value &&
+ is_nothrow_copy_constructible<key_compare>::value);
+ explicit map(const key_compare& comp);
+ map(const key_compare& comp, const allocator_type& a);
+ template <class InputIterator>
+ map(InputIterator first, InputIterator last,
+ const key_compare& comp = key_compare());
+ template <class InputIterator>
+ map(InputIterator first, InputIterator last,
+ const key_compare& comp, const allocator_type& a);
+ template<container-compatible-range<value_type> R>
+ map(from_range_t, R&& rg, const Compare& comp = Compare(), const Allocator& = Allocator()); // C++23
+ map(const map& m);
+ map(map&& m)
+ noexcept(
+ is_nothrow_move_constructible<allocator_type>::value &&
+ is_nothrow_move_constructible<key_compare>::value);
+ explicit map(const allocator_type& a);
+ map(const map& m, const allocator_type& a);
+ map(map&& m, const allocator_type& a);
+ map(initializer_list<value_type> il, const key_compare& comp = key_compare());
+ map(initializer_list<value_type> il, const key_compare& comp, const allocator_type& a);
+ template <class InputIterator>
+ map(InputIterator first, InputIterator last, const allocator_type& a)
+ : map(first, last, Compare(), a) {} // C++14
+ template<container-compatible-range<value_type> R>
+ map(from_range_t, R&& rg, const Allocator& a))
+ : map(from_range, std::forward<R>(rg), Compare(), a) { } // C++23
+ map(initializer_list<value_type> il, const allocator_type& a)
+ : map(il, Compare(), a) {} // C++14
+ ~map();
+
+ map& operator=(const map& m);
+ map& operator=(map&& m)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value &&
+ is_nothrow_move_assignable<key_compare>::value);
+ map& operator=(initializer_list<value_type> il);
+
+ // iterators:
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+
+ reverse_iterator rbegin() noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ reverse_iterator rend() noexcept;
+ const_reverse_iterator rend() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ // capacity:
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ // element access:
+ mapped_type& operator[](const key_type& k);
+ mapped_type& operator[](key_type&& k);
+
+ mapped_type& at(const key_type& k);
+ const mapped_type& at(const key_type& k) const;
+
+ // modifiers:
+ template <class... Args>
+ pair<iterator, bool> emplace(Args&&... args);
+ template <class... Args>
+ iterator emplace_hint(const_iterator position, Args&&... args);
+ pair<iterator, bool> insert(const value_type& v);
+ pair<iterator, bool> insert( value_type&& v); // C++17
+ template <class P>
+ pair<iterator, bool> insert(P&& p);
+ iterator insert(const_iterator position, const value_type& v);
+ iterator insert(const_iterator position, value_type&& v); // C++17
+ template <class P>
+ iterator insert(const_iterator position, P&& p);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+ template<container-compatible-range<value_type> R>
+ void insert_range(R&& rg); // C++23
+ void insert(initializer_list<value_type> il);
+
+ node_type extract(const_iterator position); // C++17
+ node_type extract(const key_type& x); // C++17
+ insert_return_type insert(node_type&& nh); // C++17
+ iterator insert(const_iterator hint, node_type&& nh); // C++17
+
+ template <class... Args>
+ pair<iterator, bool> try_emplace(const key_type& k, Args&&... args); // C++17
+ template <class... Args>
+ pair<iterator, bool> try_emplace(key_type&& k, Args&&... args); // C++17
+ template <class... Args>
+ iterator try_emplace(const_iterator hint, const key_type& k, Args&&... args); // C++17
+ template <class... Args>
+ iterator try_emplace(const_iterator hint, key_type&& k, Args&&... args); // C++17
+ template <class M>
+ pair<iterator, bool> insert_or_assign(const key_type& k, M&& obj); // C++17
+ template <class M>
+ pair<iterator, bool> insert_or_assign(key_type&& k, M&& obj); // C++17
+ template <class M>
+ iterator insert_or_assign(const_iterator hint, const key_type& k, M&& obj); // C++17
+ template <class M>
+ iterator insert_or_assign(const_iterator hint, key_type&& k, M&& obj); // C++17
+
+ iterator erase(const_iterator position);
+ iterator erase(iterator position); // C++14
+ size_type erase(const key_type& k);
+ iterator erase(const_iterator first, const_iterator last);
+ void clear() noexcept;
+
+ template<class C2>
+ void merge(map<Key, T, C2, Allocator>& source); // C++17
+ template<class C2>
+ void merge(map<Key, T, C2, Allocator>&& source); // C++17
+ template<class C2>
+ void merge(multimap<Key, T, C2, Allocator>& source); // C++17
+ template<class C2>
+ void merge(multimap<Key, T, C2, Allocator>&& source); // C++17
+
+ void swap(map& m)
+ noexcept(allocator_traits<allocator_type>::is_always_equal::value &&
+ is_nothrow_swappable<key_compare>::value); // C++17
+
+ // observers:
+ allocator_type get_allocator() const noexcept;
+ key_compare key_comp() const;
+ value_compare value_comp() const;
+
+ // map operations:
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ template<typename K>
+ iterator find(const K& x); // C++14
+ template<typename K>
+ const_iterator find(const K& x) const; // C++14
+
+ template<typename K>
+ size_type count(const K& x) const; // C++14
+ size_type count(const key_type& k) const;
+
+ bool contains(const key_type& x) const; // C++20
+ template<class K> bool contains(const K& x) const; // C++20
+
+ iterator lower_bound(const key_type& k);
+ const_iterator lower_bound(const key_type& k) const;
+ template<typename K>
+ iterator lower_bound(const K& x); // C++14
+ template<typename K>
+ const_iterator lower_bound(const K& x) const; // C++14
+
+ iterator upper_bound(const key_type& k);
+ const_iterator upper_bound(const key_type& k) const;
+ template<typename K>
+ iterator upper_bound(const K& x); // C++14
+ template<typename K>
+ const_iterator upper_bound(const K& x) const; // C++14
+
+ pair<iterator,iterator> equal_range(const key_type& k);
+ pair<const_iterator,const_iterator> equal_range(const key_type& k) const;
+ template<typename K>
+ pair<iterator,iterator> equal_range(const K& x); // C++14
+ template<typename K>
+ pair<const_iterator,const_iterator> equal_range(const K& x) const; // C++14
+};
+
+template <class InputIterator,
+ class Compare = less<iter_key_t<InputIterator>>,
+ class Allocator = allocator<iter_to_alloc_t<InputIterator>>>
+map(InputIterator, InputIterator, Compare = Compare(), Allocator = Allocator())
+ -> map<iter_key_t<InputIterator>, iter_val_t<InputIterator>, Compare, Allocator>; // C++17
+
+template<ranges::input_range R, class Compare = less<range-key-type<R>,
+ class Allocator = allocator<range-to-alloc-type<R>>>
+ map(from_range_t, R&&, Compare = Compare(), Allocator = Allocator())
+ -> map<range-key-type<R>, range-mapped-type<R>, Compare, Allocator>; // C++23
+
+template<class Key, class T, class Compare = less<Key>,
+ class Allocator = allocator<pair<const Key, T>>>
+map(initializer_list<pair<const Key, T>>, Compare = Compare(), Allocator = Allocator())
+ -> map<Key, T, Compare, Allocator>; // C++17
+
+template <class InputIterator, class Allocator>
+map(InputIterator, InputIterator, Allocator)
+ -> map<iter_key_t<InputIterator>, iter_val_t<InputIterator>, less<iter_key_t<InputIterator>>,
+ Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator>
+ map(from_range_t, R&&, Allocator)
+ -> map<range-key-type<R>, range-mapped-type<R>, less<range-key-type<R>>, Allocator>; // C++23
+
+template<class Key, class T, class Allocator>
+map(initializer_list<pair<const Key, T>>, Allocator) -> map<Key, T, less<Key>, Allocator>; // C++17
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator==(const map<Key, T, Compare, Allocator>& x,
+ const map<Key, T, Compare, Allocator>& y);
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator< (const map<Key, T, Compare, Allocator>& x,
+ const map<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator!=(const map<Key, T, Compare, Allocator>& x,
+ const map<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator> (const map<Key, T, Compare, Allocator>& x,
+ const map<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator>=(const map<Key, T, Compare, Allocator>& x,
+ const map<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator<=(const map<Key, T, Compare, Allocator>& x,
+ const map<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template<class Key, class T, class Compare, class Allocator>
+ synth-three-way-result<pair<const Key, T>>
+ operator<=>(const map<Key, T, Compare, Allocator>& x,
+ const map<Key, T, Compare, Allocator>& y); // since C++20
+
+// specialized algorithms:
+template <class Key, class T, class Compare, class Allocator>
+void
+swap(map<Key, T, Compare, Allocator>& x, map<Key, T, Compare, Allocator>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class Key, class T, class Compare, class Allocator, class Predicate>
+typename map<Key, T, Compare, Allocator>::size_type
+erase_if(map<Key, T, Compare, Allocator>& c, Predicate pred); // C++20
+
+
+template <class Key, class T, class Compare = less<Key>,
+ class Allocator = allocator<pair<const Key, T>>>
+class multimap
+{
+public:
+ // types:
+ typedef Key key_type;
+ typedef T mapped_type;
+ typedef pair<const key_type,mapped_type> value_type;
+ typedef Compare key_compare;
+ typedef Allocator allocator_type;
+ typedef typename allocator_type::reference reference;
+ typedef typename allocator_type::const_reference const_reference;
+ typedef typename allocator_type::size_type size_type;
+ typedef typename allocator_type::difference_type difference_type;
+ typedef typename allocator_type::pointer pointer;
+ typedef typename allocator_type::const_pointer const_pointer;
+
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+ typedef unspecified node_type; // C++17
+
+ class value_compare
+ {
+ friend class multimap;
+ protected:
+ key_compare comp;
+ value_compare(key_compare c);
+ public:
+ typedef bool result_type; // deprecated in C++17, removed in C++20
+ typedef value_type first_argument_type; // deprecated in C++17, removed in C++20
+ typedef value_type second_argument_type; // deprecated in C++17, removed in C++20
+ bool operator()(const value_type& x, const value_type& y) const;
+ };
+
+ // construct/copy/destroy:
+ multimap()
+ noexcept(
+ is_nothrow_default_constructible<allocator_type>::value &&
+ is_nothrow_default_constructible<key_compare>::value &&
+ is_nothrow_copy_constructible<key_compare>::value);
+ explicit multimap(const key_compare& comp);
+ multimap(const key_compare& comp, const allocator_type& a);
+ template <class InputIterator>
+ multimap(InputIterator first, InputIterator last, const key_compare& comp);
+ template <class InputIterator>
+ multimap(InputIterator first, InputIterator last, const key_compare& comp,
+ const allocator_type& a);
+ template<container-compatible-range<value_type> R>
+ multimap(from_range_t, R&& rg,
+ const Compare& comp = Compare(), const Allocator& = Allocator()); // C++23
+ multimap(const multimap& m);
+ multimap(multimap&& m)
+ noexcept(
+ is_nothrow_move_constructible<allocator_type>::value &&
+ is_nothrow_move_constructible<key_compare>::value);
+ explicit multimap(const allocator_type& a);
+ multimap(const multimap& m, const allocator_type& a);
+ multimap(multimap&& m, const allocator_type& a);
+ multimap(initializer_list<value_type> il, const key_compare& comp = key_compare());
+ multimap(initializer_list<value_type> il, const key_compare& comp,
+ const allocator_type& a);
+ template <class InputIterator>
+ multimap(InputIterator first, InputIterator last, const allocator_type& a)
+ : multimap(first, last, Compare(), a) {} // C++14
+ template<container-compatible-range<value_type> R>
+ multimap(from_range_t, R&& rg, const Allocator& a))
+ : multimap(from_range, std::forward<R>(rg), Compare(), a) { } // C++23
+ multimap(initializer_list<value_type> il, const allocator_type& a)
+ : multimap(il, Compare(), a) {} // C++14
+ ~multimap();
+
+ multimap& operator=(const multimap& m);
+ multimap& operator=(multimap&& m)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value &&
+ is_nothrow_move_assignable<key_compare>::value);
+ multimap& operator=(initializer_list<value_type> il);
+
+ // iterators:
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+
+ reverse_iterator rbegin() noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ reverse_iterator rend() noexcept;
+ const_reverse_iterator rend() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ // capacity:
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ // modifiers:
+ template <class... Args>
+ iterator emplace(Args&&... args);
+ template <class... Args>
+ iterator emplace_hint(const_iterator position, Args&&... args);
+ iterator insert(const value_type& v);
+ iterator insert( value_type&& v); // C++17
+ template <class P>
+ iterator insert(P&& p);
+ iterator insert(const_iterator position, const value_type& v);
+ iterator insert(const_iterator position, value_type&& v); // C++17
+ template <class P>
+ iterator insert(const_iterator position, P&& p);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+ template<container-compatible-range<value_type> R>
+ void insert_range(R&& rg); // C++23
+ void insert(initializer_list<value_type> il);
+
+ node_type extract(const_iterator position); // C++17
+ node_type extract(const key_type& x); // C++17
+ iterator insert(node_type&& nh); // C++17
+ iterator insert(const_iterator hint, node_type&& nh); // C++17
+
+ iterator erase(const_iterator position);
+ iterator erase(iterator position); // C++14
+ size_type erase(const key_type& k);
+ iterator erase(const_iterator first, const_iterator last);
+ void clear() noexcept;
+
+ template<class C2>
+ void merge(multimap<Key, T, C2, Allocator>& source); // C++17
+ template<class C2>
+ void merge(multimap<Key, T, C2, Allocator>&& source); // C++17
+ template<class C2>
+ void merge(map<Key, T, C2, Allocator>& source); // C++17
+ template<class C2>
+ void merge(map<Key, T, C2, Allocator>&& source); // C++17
+
+ void swap(multimap& m)
+ noexcept(allocator_traits<allocator_type>::is_always_equal::value &&
+ is_nothrow_swappable<key_compare>::value); // C++17
+
+ // observers:
+ allocator_type get_allocator() const noexcept;
+ key_compare key_comp() const;
+ value_compare value_comp() const;
+
+ // map operations:
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ template<typename K>
+ iterator find(const K& x); // C++14
+ template<typename K>
+ const_iterator find(const K& x) const; // C++14
+
+ template<typename K>
+ size_type count(const K& x) const; // C++14
+ size_type count(const key_type& k) const;
+
+ bool contains(const key_type& x) const; // C++20
+ template<class K> bool contains(const K& x) const; // C++20
+
+ iterator lower_bound(const key_type& k);
+ const_iterator lower_bound(const key_type& k) const;
+ template<typename K>
+ iterator lower_bound(const K& x); // C++14
+ template<typename K>
+ const_iterator lower_bound(const K& x) const; // C++14
+
+ iterator upper_bound(const key_type& k);
+ const_iterator upper_bound(const key_type& k) const;
+ template<typename K>
+ iterator upper_bound(const K& x); // C++14
+ template<typename K>
+ const_iterator upper_bound(const K& x) const; // C++14
+
+ pair<iterator,iterator> equal_range(const key_type& k);
+ pair<const_iterator,const_iterator> equal_range(const key_type& k) const;
+ template<typename K>
+ pair<iterator,iterator> equal_range(const K& x); // C++14
+ template<typename K>
+ pair<const_iterator,const_iterator> equal_range(const K& x) const; // C++14
+};
+
+template <class InputIterator,
+ class Compare = less<iter_key_t<InputIterator>>,
+ class Allocator = allocator<iter_to_alloc_t<InputIterator>>>
+multimap(InputIterator, InputIterator, Compare = Compare(), Allocator = Allocator())
+ -> multimap<iter_key_t<InputIterator>, iter_val_t<InputIterator>, Compare, Allocator>; // C++17
+
+template<ranges::input_range R, class Compare = less<range-key-type<R>>,
+ class Allocator = allocator<range-to-alloc-type<R>>>
+ multimap(from_range_t, R&&, Compare = Compare(), Allocator = Allocator())
+ -> multimap<range-key-type<R>, range-mapped-type<R>, Compare, Allocator>; // C++23
+
+template<class Key, class T, class Compare = less<Key>,
+ class Allocator = allocator<pair<const Key, T>>>
+multimap(initializer_list<pair<const Key, T>>, Compare = Compare(), Allocator = Allocator())
+ -> multimap<Key, T, Compare, Allocator>; // C++17
+
+template <class InputIterator, class Allocator>
+multimap(InputIterator, InputIterator, Allocator)
+ -> multimap<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
+ less<iter_key_t<InputIterator>>, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator>
+ multimap(from_range_t, R&&, Allocator)
+ -> multimap<range-key-type<R>, range-mapped-type<R>, less<range-key-type<R>>, Allocator>; // C++23
+
+template<class Key, class T, class Allocator>
+multimap(initializer_list<pair<const Key, T>>, Allocator)
+ -> multimap<Key, T, less<Key>, Allocator>; // C++17
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator==(const multimap<Key, T, Compare, Allocator>& x,
+ const multimap<Key, T, Compare, Allocator>& y);
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator< (const multimap<Key, T, Compare, Allocator>& x,
+ const multimap<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator!=(const multimap<Key, T, Compare, Allocator>& x,
+ const multimap<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator> (const multimap<Key, T, Compare, Allocator>& x,
+ const multimap<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator>=(const multimap<Key, T, Compare, Allocator>& x,
+ const multimap<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class T, class Compare, class Allocator>
+bool
+operator<=(const multimap<Key, T, Compare, Allocator>& x,
+ const multimap<Key, T, Compare, Allocator>& y); // removed in C++20
+
+template<class Key, class T, class Compare, class Allocator>
+ synth-three-way-result<pair<const Key, T>>
+ operator<=>(const multimap<Key, T, Compare, Allocator>& x,
+ const multimap<Key, T, Compare, Allocator>& y); // since c++20
+
+// specialized algorithms:
+template <class Key, class T, class Compare, class Allocator>
+void
+swap(multimap<Key, T, Compare, Allocator>& x,
+ multimap<Key, T, Compare, Allocator>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class Key, class T, class Compare, class Allocator, class Predicate>
+typename multimap<Key, T, Compare, Allocator>::size_type
+erase_if(multimap<Key, T, Compare, Allocator>& c, Predicate pred); // C++20
+
+} // std
+
+*/
+
+#include <__algorithm/equal.h>
+#include <__algorithm/lexicographical_compare.h>
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__assert>
+#include <__config>
+#include <__functional/binary_function.h>
+#include <__functional/is_transparent.h>
+#include <__functional/operations.h>
+#include <__iterator/erase_if_container.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/ranges_iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__node_handle>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__tree>
+#include <__type_traits/is_allocator.h>
+#include <__utility/forward.h>
+#include <__utility/piecewise_construct.h>
+#include <__utility/swap.h>
+#include <stdexcept>
+#include <tuple>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [associative.map.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Key,
+ class _CP,
+ class _Compare,
+ bool = is_empty<_Compare>::value && !__libcpp_is_final<_Compare>::value>
+class __map_value_compare : private _Compare {
+public:
+ _LIBCPP_HIDE_FROM_ABI __map_value_compare() _NOEXCEPT_(is_nothrow_default_constructible<_Compare>::value)
+ : _Compare() {}
+ _LIBCPP_HIDE_FROM_ABI __map_value_compare(_Compare __c) _NOEXCEPT_(is_nothrow_copy_constructible<_Compare>::value)
+ : _Compare(__c) {}
+ _LIBCPP_HIDE_FROM_ABI const _Compare& key_comp() const _NOEXCEPT { return *this; }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _CP& __x, const _CP& __y) const {
+ return static_cast<const _Compare&>(*this)(__x.__get_value().first, __y.__get_value().first);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _CP& __x, const _Key& __y) const {
+ return static_cast<const _Compare&>(*this)(__x.__get_value().first, __y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Key& __x, const _CP& __y) const {
+ return static_cast<const _Compare&>(*this)(__x, __y.__get_value().first);
+ }
+ _LIBCPP_HIDE_FROM_ABI void swap(__map_value_compare& __y) _NOEXCEPT_(__is_nothrow_swappable_v<_Compare>) {
+ using std::swap;
+ swap(static_cast<_Compare&>(*this), static_cast<_Compare&>(__y));
+ }
+
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _K2& __x, const _CP& __y) const {
+ return static_cast<const _Compare&>(*this)(__x, __y.__get_value().first);
+ }
+
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _CP& __x, const _K2& __y) const {
+ return static_cast<const _Compare&>(*this)(__x.__get_value().first, __y);
+ }
+#endif
+};
+
+template <class _Key, class _CP, class _Compare>
+class __map_value_compare<_Key, _CP, _Compare, false> {
+ _Compare __comp_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __map_value_compare() _NOEXCEPT_(is_nothrow_default_constructible<_Compare>::value)
+ : __comp_() {}
+ _LIBCPP_HIDE_FROM_ABI __map_value_compare(_Compare __c) _NOEXCEPT_(is_nothrow_copy_constructible<_Compare>::value)
+ : __comp_(__c) {}
+ _LIBCPP_HIDE_FROM_ABI const _Compare& key_comp() const _NOEXCEPT { return __comp_; }
+
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _CP& __x, const _CP& __y) const {
+ return __comp_(__x.__get_value().first, __y.__get_value().first);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _CP& __x, const _Key& __y) const {
+ return __comp_(__x.__get_value().first, __y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Key& __x, const _CP& __y) const {
+ return __comp_(__x, __y.__get_value().first);
+ }
+ void swap(__map_value_compare& __y) _NOEXCEPT_(__is_nothrow_swappable_v<_Compare>) {
+ using std::swap;
+ swap(__comp_, __y.__comp_);
+ }
+
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _K2& __x, const _CP& __y) const {
+ return __comp_(__x, __y.__get_value().first);
+ }
+
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _CP& __x, const _K2& __y) const {
+ return __comp_(__x.__get_value().first, __y);
+ }
+#endif
+};
+
+template <class _Key, class _CP, class _Compare, bool __b>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(__map_value_compare<_Key, _CP, _Compare, __b>& __x, __map_value_compare<_Key, _CP, _Compare, __b>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+template <class _Allocator>
+class __map_node_destructor {
+ typedef _Allocator allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+
+private:
+ allocator_type& __na_;
+
+public:
+ bool __first_constructed;
+ bool __second_constructed;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __map_node_destructor(allocator_type& __na) _NOEXCEPT
+ : __na_(__na),
+ __first_constructed(false),
+ __second_constructed(false) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __map_node_destructor(__tree_node_destructor<allocator_type>&& __x) _NOEXCEPT
+ : __na_(__x.__na_),
+ __first_constructed(__x.__value_constructed),
+ __second_constructed(__x.__value_constructed) {
+ __x.__value_constructed = false;
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ __map_node_destructor& operator=(const __map_node_destructor&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI void operator()(pointer __p) _NOEXCEPT {
+ if (__second_constructed)
+ __alloc_traits::destroy(__na_, std::addressof(__p->__value_.__get_value().second));
+ if (__first_constructed)
+ __alloc_traits::destroy(__na_, std::addressof(__p->__value_.__get_value().first));
+ if (__p)
+ __alloc_traits::deallocate(__na_, __p, 1);
+ }
+};
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+class map;
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+class multimap;
+template <class _TreeIterator>
+class __map_const_iterator;
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp>
+struct _LIBCPP_STANDALONE_DEBUG __value_type {
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef pair<key_type&, mapped_type&> __nc_ref_pair_type;
+ typedef pair<key_type&&, mapped_type&&> __nc_rref_pair_type;
+
+private:
+ value_type __cc_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI value_type& __get_value() {
+# if _LIBCPP_STD_VER >= 17
+ return *std::launder(std::addressof(__cc_));
+# else
+ return __cc_;
+# endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const value_type& __get_value() const {
+# if _LIBCPP_STD_VER >= 17
+ return *std::launder(std::addressof(__cc_));
+# else
+ return __cc_;
+# endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __nc_ref_pair_type __ref() {
+ value_type& __v = __get_value();
+ return __nc_ref_pair_type(const_cast<key_type&>(__v.first), __v.second);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __nc_rref_pair_type __move() {
+ value_type& __v = __get_value();
+ return __nc_rref_pair_type(std::move(const_cast<key_type&>(__v.first)), std::move(__v.second));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __value_type& operator=(const __value_type& __v) {
+ __ref() = __v.__get_value();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __value_type& operator=(__value_type&& __v) {
+ __ref() = __v.__move();
+ return *this;
+ }
+
+ template <class _ValueTp, __enable_if_t<__is_same_uncvref<_ValueTp, value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI __value_type& operator=(_ValueTp&& __v) {
+ __ref() = std::forward<_ValueTp>(__v);
+ return *this;
+ }
+
+ __value_type() = delete;
+ ~__value_type() = delete;
+ __value_type(const __value_type&) = delete;
+ __value_type(__value_type&&) = delete;
+};
+
+#else
+
+template <class _Key, class _Tp>
+struct __value_type {
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef pair<const key_type, mapped_type> value_type;
+
+private:
+ value_type __cc_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI value_type& __get_value() { return __cc_; }
+ _LIBCPP_HIDE_FROM_ABI const value_type& __get_value() const { return __cc_; }
+
+ __value_type() = delete;
+ __value_type(__value_type const&) = delete;
+ __value_type& operator=(__value_type const&) = delete;
+ ~__value_type() = delete;
+};
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+struct __extract_key_value_types;
+
+template <class _Key, class _Tp>
+struct __extract_key_value_types<__value_type<_Key, _Tp> > {
+ typedef _Key const __key_type;
+ typedef _Tp __mapped_type;
+};
+
+template <class _TreeIterator>
+class _LIBCPP_TEMPLATE_VIS __map_iterator {
+ typedef typename _TreeIterator::_NodeTypes _NodeTypes;
+ typedef typename _TreeIterator::__pointer_traits __pointer_traits;
+
+ _TreeIterator __i_;
+
+public:
+ typedef bidirectional_iterator_tag iterator_category;
+ typedef typename _NodeTypes::__map_value_type value_type;
+ typedef typename _TreeIterator::difference_type difference_type;
+ typedef value_type& reference;
+ typedef typename _NodeTypes::__map_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __map_iterator() _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI __map_iterator(_TreeIterator __i) _NOEXCEPT : __i_(__i) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __i_->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return pointer_traits<pointer>::pointer_to(__i_->__get_value()); }
+
+ _LIBCPP_HIDE_FROM_ABI __map_iterator& operator++() {
+ ++__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __map_iterator operator++(int) {
+ __map_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __map_iterator& operator--() {
+ --__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __map_iterator operator--(int) {
+ __map_iterator __t(*this);
+ --(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __map_iterator& __x, const __map_iterator& __y) {
+ return __x.__i_ == __y.__i_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __map_iterator& __x, const __map_iterator& __y) {
+ return __x.__i_ != __y.__i_;
+ }
+
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS map;
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS multimap;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __map_const_iterator;
+};
+
+template <class _TreeIterator>
+class _LIBCPP_TEMPLATE_VIS __map_const_iterator {
+ typedef typename _TreeIterator::_NodeTypes _NodeTypes;
+ typedef typename _TreeIterator::__pointer_traits __pointer_traits;
+
+ _TreeIterator __i_;
+
+public:
+ typedef bidirectional_iterator_tag iterator_category;
+ typedef typename _NodeTypes::__map_value_type value_type;
+ typedef typename _TreeIterator::difference_type difference_type;
+ typedef const value_type& reference;
+ typedef typename _NodeTypes::__const_map_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __map_const_iterator() _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI __map_const_iterator(_TreeIterator __i) _NOEXCEPT : __i_(__i) {}
+ _LIBCPP_HIDE_FROM_ABI
+ __map_const_iterator(__map_iterator< typename _TreeIterator::__non_const_iterator> __i) _NOEXCEPT : __i_(__i.__i_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __i_->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return pointer_traits<pointer>::pointer_to(__i_->__get_value()); }
+
+ _LIBCPP_HIDE_FROM_ABI __map_const_iterator& operator++() {
+ ++__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __map_const_iterator operator++(int) {
+ __map_const_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __map_const_iterator& operator--() {
+ --__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __map_const_iterator operator--(int) {
+ __map_const_iterator __t(*this);
+ --(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __map_const_iterator& __x, const __map_const_iterator& __y) {
+ return __x.__i_ == __y.__i_;
+ }
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __map_const_iterator& __x, const __map_const_iterator& __y) {
+ return __x.__i_ != __y.__i_;
+ }
+
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS map;
+ template <class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS multimap;
+ template <class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS __tree_const_iterator;
+};
+
+template <class _Key, class _Tp, class _Compare = less<_Key>, class _Allocator = allocator<pair<const _Key, _Tp> > >
+class _LIBCPP_TEMPLATE_VIS map {
+public:
+ // types:
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef __type_identity_t<_Compare> key_compare;
+ typedef __type_identity_t<_Allocator> allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+
+ static_assert(is_same<typename allocator_type::value_type, value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+ class _LIBCPP_TEMPLATE_VIS value_compare : public __binary_function<value_type, value_type, bool> {
+ friend class map;
+
+ protected:
+ key_compare comp;
+
+ _LIBCPP_HIDE_FROM_ABI value_compare(key_compare __c) : comp(__c) {}
+
+ public:
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const value_type& __x, const value_type& __y) const {
+ return comp(__x.first, __y.first);
+ }
+ };
+
+private:
+ typedef std::__value_type<key_type, mapped_type> __value_type;
+ typedef __map_value_compare<key_type, __value_type, key_compare> __vc;
+ typedef __rebind_alloc<allocator_traits<allocator_type>, __value_type> __allocator_type;
+ typedef __tree<__value_type, __vc, __allocator_type> __base;
+ typedef typename __base::__node_traits __node_traits;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+
+ __base __tree_;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+ typedef typename __alloc_traits::size_type size_type;
+ typedef typename __alloc_traits::difference_type difference_type;
+ typedef __map_iterator<typename __base::iterator> iterator;
+ typedef __map_const_iterator<typename __base::const_iterator> const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+#if _LIBCPP_STD_VER >= 17
+ typedef __map_node_handle<typename __base::__node, allocator_type> node_type;
+ typedef __insert_return_type<iterator, node_type> insert_return_type;
+#endif
+
+ template <class _Key2, class _Value2, class _Comp2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS map;
+ template <class _Key2, class _Value2, class _Comp2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS multimap;
+
+ _LIBCPP_HIDE_FROM_ABI map() _NOEXCEPT_(
+ is_nothrow_default_constructible<allocator_type>::value&& is_nothrow_default_constructible<key_compare>::value&&
+ is_nothrow_copy_constructible<key_compare>::value)
+ : __tree_(__vc(key_compare())) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit map(const key_compare& __comp) _NOEXCEPT_(
+ is_nothrow_default_constructible<allocator_type>::value&& is_nothrow_copy_constructible<key_compare>::value)
+ : __tree_(__vc(__comp)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit map(const key_compare& __comp, const allocator_type& __a)
+ : __tree_(__vc(__comp), typename __base::allocator_type(__a)) {}
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI map(_InputIterator __f, _InputIterator __l, const key_compare& __comp = key_compare())
+ : __tree_(__vc(__comp)) {
+ insert(__f, __l);
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ map(_InputIterator __f, _InputIterator __l, const key_compare& __comp, const allocator_type& __a)
+ : __tree_(__vc(__comp), typename __base::allocator_type(__a)) {
+ insert(__f, __l);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI
+ map(from_range_t,
+ _Range&& __range,
+ const key_compare& __comp = key_compare(),
+ const allocator_type& __a = allocator_type())
+ : __tree_(__vc(__comp), typename __base::allocator_type(__a)) {
+ insert_range(std::forward<_Range>(__range));
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI map(_InputIterator __f, _InputIterator __l, const allocator_type& __a)
+ : map(__f, __l, key_compare(), __a) {}
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI map(from_range_t, _Range&& __range, const allocator_type& __a)
+ : map(from_range, std::forward<_Range>(__range), key_compare(), __a) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI map(const map& __m) : __tree_(__m.__tree_) { insert(__m.begin(), __m.end()); }
+
+ _LIBCPP_HIDE_FROM_ABI map& operator=(const map& __m) {
+#ifndef _LIBCPP_CXX03_LANG
+ __tree_ = __m.__tree_;
+#else
+ if (this != std::addressof(__m)) {
+ __tree_.clear();
+ __tree_.value_comp() = __m.__tree_.value_comp();
+ __tree_.__copy_assign_alloc(__m.__tree_);
+ insert(__m.begin(), __m.end());
+ }
+#endif
+ return *this;
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI map(map&& __m) noexcept(is_nothrow_move_constructible<__base>::value)
+ : __tree_(std::move(__m.__tree_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI map(map&& __m, const allocator_type& __a);
+
+ _LIBCPP_HIDE_FROM_ABI map& operator=(map&& __m) noexcept(is_nothrow_move_assignable<__base>::value) {
+ __tree_ = std::move(__m.__tree_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI map(initializer_list<value_type> __il, const key_compare& __comp = key_compare())
+ : __tree_(__vc(__comp)) {
+ insert(__il.begin(), __il.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI map(initializer_list<value_type> __il, const key_compare& __comp, const allocator_type& __a)
+ : __tree_(__vc(__comp), typename __base::allocator_type(__a)) {
+ insert(__il.begin(), __il.end());
+ }
+
+# if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI map(initializer_list<value_type> __il, const allocator_type& __a)
+ : map(__il, key_compare(), __a) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI map& operator=(initializer_list<value_type> __il) {
+ __tree_.__assign_unique(__il.begin(), __il.end());
+ return *this;
+ }
+
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI explicit map(const allocator_type& __a) : __tree_(typename __base::allocator_type(__a)) {}
+
+ _LIBCPP_HIDE_FROM_ABI map(const map& __m, const allocator_type& __a)
+ : __tree_(__m.__tree_.value_comp(), typename __base::allocator_type(__a)) {
+ insert(__m.begin(), __m.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~map() { static_assert(sizeof(__diagnose_non_const_comparator<_Key, _Compare>()), ""); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __tree_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __tree_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __tree_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __tree_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() _NOEXCEPT { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const _NOEXCEPT { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() _NOEXCEPT { return reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const _NOEXCEPT { return const_reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const _NOEXCEPT { return rbegin(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __tree_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __tree_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __tree_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI mapped_type& operator[](const key_type& __k);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI mapped_type& operator[](key_type&& __k);
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI mapped_type& at(const key_type& __k);
+ _LIBCPP_HIDE_FROM_ABI const mapped_type& at(const key_type& __k) const;
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT { return allocator_type(__tree_.__alloc()); }
+ _LIBCPP_HIDE_FROM_ABI key_compare key_comp() const { return __tree_.value_comp().key_comp(); }
+ _LIBCPP_HIDE_FROM_ABI value_compare value_comp() const { return value_compare(__tree_.value_comp().key_comp()); }
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> emplace(_Args&&... __args) {
+ return __tree_.__emplace_unique(std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator __p, _Args&&... __args) {
+ return __tree_.__emplace_hint_unique(__p.__i_, std::forward<_Args>(__args)...);
+ }
+
+ template <class _Pp, __enable_if_t<is_constructible<value_type, _Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(_Pp&& __p) {
+ return __tree_.__insert_unique(std::forward<_Pp>(__p));
+ }
+
+ template <class _Pp, __enable_if_t<is_constructible<value_type, _Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __pos, _Pp&& __p) {
+ return __tree_.__insert_unique(__pos.__i_, std::forward<_Pp>(__p));
+ }
+
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(const value_type& __v) { return __tree_.__insert_unique(__v); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __v) {
+ return __tree_.__insert_unique(__p.__i_, __v);
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(value_type&& __v) {
+ return __tree_.__insert_unique(std::move(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __v) {
+ return __tree_.__insert_unique(__p.__i_, std::move(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+#endif
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __f, _InputIterator __l) {
+ for (const_iterator __e = cend(); __f != __l; ++__f)
+ insert(__e.__i_, *__f);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ const_iterator __end = cend();
+ for (auto&& __element : __range) {
+ insert(__end.__i_, std::forward<decltype(__element)>(__element));
+ }
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> try_emplace(const key_type& __k, _Args&&... __args) {
+ return __tree_.__emplace_unique_key_args(
+ __k,
+ std::piecewise_construct,
+ std::forward_as_tuple(__k),
+ std::forward_as_tuple(std::forward<_Args>(__args)...));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> try_emplace(key_type&& __k, _Args&&... __args) {
+ return __tree_.__emplace_unique_key_args(
+ __k,
+ std::piecewise_construct,
+ std::forward_as_tuple(std::move(__k)),
+ std::forward_as_tuple(std::forward<_Args>(__args)...));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator try_emplace(const_iterator __h, const key_type& __k, _Args&&... __args) {
+ return __tree_
+ .__emplace_hint_unique_key_args(
+ __h.__i_,
+ __k,
+ std::piecewise_construct,
+ std::forward_as_tuple(__k),
+ std::forward_as_tuple(std::forward<_Args>(__args)...))
+ .first;
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator try_emplace(const_iterator __h, key_type&& __k, _Args&&... __args) {
+ return __tree_
+ .__emplace_hint_unique_key_args(
+ __h.__i_,
+ __k,
+ std::piecewise_construct,
+ std::forward_as_tuple(std::move(__k)),
+ std::forward_as_tuple(std::forward<_Args>(__args)...))
+ .first;
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert_or_assign(const key_type& __k, _Vp&& __v) {
+ iterator __p = lower_bound(__k);
+ if (__p != end() && !key_comp()(__k, __p->first)) {
+ __p->second = std::forward<_Vp>(__v);
+ return std::make_pair(__p, false);
+ }
+ return std::make_pair(emplace_hint(__p, __k, std::forward<_Vp>(__v)), true);
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert_or_assign(key_type&& __k, _Vp&& __v) {
+ iterator __p = lower_bound(__k);
+ if (__p != end() && !key_comp()(__k, __p->first)) {
+ __p->second = std::forward<_Vp>(__v);
+ return std::make_pair(__p, false);
+ }
+ return std::make_pair(emplace_hint(__p, std::move(__k), std::forward<_Vp>(__v)), true);
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_or_assign(const_iterator __h, const key_type& __k, _Vp&& __v) {
+ auto [__r, __inserted] = __tree_.__emplace_hint_unique_key_args(__h.__i_, __k, __k, std::forward<_Vp>(__v));
+
+ if (!__inserted)
+ __r->__get_value().second = std::forward<_Vp>(__v);
+
+ return __r;
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_or_assign(const_iterator __h, key_type&& __k, _Vp&& __v) {
+ auto [__r, __inserted] =
+ __tree_.__emplace_hint_unique_key_args(__h.__i_, __k, std::move(__k), std::forward<_Vp>(__v));
+
+ if (!__inserted)
+ __r->__get_value().second = std::forward<_Vp>(__v);
+
+ return __r;
+ }
+
+#endif // _LIBCPP_STD_VER >= 17
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p) { return __tree_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(iterator __p) { return __tree_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __tree_.__erase_unique(__k); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __f, const_iterator __l) {
+ return __tree_.erase(__f.__i_, __l.__i_);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __tree_.clear(); }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI insert_return_type insert(node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to map::insert()");
+ return __tree_.template __node_handle_insert_unique< node_type, insert_return_type>(std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to map::insert()");
+ return __tree_.template __node_handle_insert_unique<node_type>(__hint.__i_, std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(key_type const& __key) {
+ return __tree_.template __node_handle_extract<node_type>(__key);
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(const_iterator __it) {
+ return __tree_.template __node_handle_extract<node_type>(__it.__i_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(map<key_type, mapped_type, _Compare2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_unique(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(map<key_type, mapped_type, _Compare2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_unique(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(multimap<key_type, mapped_type, _Compare2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_unique(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(multimap<key_type, mapped_type, _Compare2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_unique(__source.__tree_);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void swap(map& __m) _NOEXCEPT_(__is_nothrow_swappable_v<__base>) { __tree_.swap(__m.__tree_); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __tree_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __tree_.find(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _K2& __k) {
+ return __tree_.find(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _K2& __k) const {
+ return __tree_.find(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __tree_.__count_unique(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _K2& __k) const {
+ return __tree_.__count_multi(__k);
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __k) const { return find(__k) != end(); }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _K2& __k) const {
+ return find(__k) != end();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const key_type& __k) { return __tree_.lower_bound(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const key_type& __k) const { return __tree_.lower_bound(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const _K2& __k) {
+ return __tree_.lower_bound(__k);
+ }
+
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const _K2& __k) const {
+ return __tree_.lower_bound(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const key_type& __k) { return __tree_.upper_bound(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const key_type& __k) const { return __tree_.upper_bound(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const _K2& __k) {
+ return __tree_.upper_bound(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const _K2& __k) const {
+ return __tree_.upper_bound(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __tree_.__equal_range_unique(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __tree_.__equal_range_unique(__k);
+ }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _K2& __k) {
+ return __tree_.__equal_range_multi(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _K2& __k) const {
+ return __tree_.__equal_range_multi(__k);
+ }
+#endif
+
+private:
+ typedef typename __base::__node __node;
+ typedef typename __base::__node_allocator __node_allocator;
+ typedef typename __base::__node_pointer __node_pointer;
+ typedef typename __base::__node_base_pointer __node_base_pointer;
+ typedef typename __base::__parent_pointer __parent_pointer;
+
+ typedef __map_node_destructor<__node_allocator> _Dp;
+ typedef unique_ptr<__node, _Dp> __node_holder;
+
+#ifdef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __node_holder __construct_node_with_key(const key_type& __k);
+#endif
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Compare = less<__iter_key_type<_InputIterator>>,
+ class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value, void>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+map(_InputIterator, _InputIterator, _Compare = _Compare(), _Allocator = _Allocator())
+ -> map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Compare, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Compare = less<__range_key_type<_Range>>,
+ class _Allocator = allocator<__range_to_alloc_type<_Range>>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+map(from_range_t, _Range&&, _Compare = _Compare(), _Allocator = _Allocator())
+ -> map<__range_key_type<_Range>, __range_mapped_type<_Range>, _Compare, _Allocator>;
+# endif
+
+template <class _Key,
+ class _Tp,
+ class _Compare = less<remove_const_t<_Key>>,
+ class _Allocator = allocator<pair<const _Key, _Tp>>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+map(initializer_list<pair<_Key, _Tp>>,
+ _Compare = _Compare(),
+ _Allocator = _Allocator()) -> map<remove_const_t<_Key>, _Tp, _Compare, _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+map(_InputIterator, _InputIterator, _Allocator)
+ -> map<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ less<__iter_key_type<_InputIterator>>,
+ _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+map(from_range_t, _Range&&, _Allocator)
+ -> map<__range_key_type<_Range>, __range_mapped_type<_Range>, less<__range_key_type<_Range>>, _Allocator>;
+# endif
+
+template <class _Key, class _Tp, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+map(initializer_list<pair<_Key, _Tp>>,
+ _Allocator) -> map<remove_const_t<_Key>, _Tp, less<remove_const_t<_Key>>, _Allocator>;
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+map<_Key, _Tp, _Compare, _Allocator>::map(map&& __m, const allocator_type& __a)
+ : __tree_(std::move(__m.__tree_), typename __base::allocator_type(__a)) {
+ if (__a != __m.get_allocator()) {
+ const_iterator __e = cend();
+ while (!__m.empty())
+ __tree_.__insert_unique(__e.__i_, __m.__tree_.remove(__m.begin().__i_)->__value_.__move());
+ }
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+_Tp& map<_Key, _Tp, _Compare, _Allocator>::operator[](const key_type& __k) {
+ return __tree_
+ .__emplace_unique_key_args(__k, std::piecewise_construct, std::forward_as_tuple(__k), std::forward_as_tuple())
+ .first->__get_value()
+ .second;
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+_Tp& map<_Key, _Tp, _Compare, _Allocator>::operator[](key_type&& __k) {
+ // TODO investigate this clang-tidy warning.
+ // NOLINTBEGIN(bugprone-use-after-move)
+ return __tree_
+ .__emplace_unique_key_args(
+ __k, std::piecewise_construct, std::forward_as_tuple(std::move(__k)), std::forward_as_tuple())
+ .first->__get_value()
+ .second;
+ // NOLINTEND(bugprone-use-after-move)
+}
+
+#else // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+typename map<_Key, _Tp, _Compare, _Allocator>::__node_holder
+map<_Key, _Tp, _Compare, _Allocator>::__construct_node_with_key(const key_type& __k) {
+ __node_allocator& __na = __tree_.__node_alloc();
+ __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
+ __node_traits::construct(__na, std::addressof(__h->__value_.__get_value().first), __k);
+ __h.get_deleter().__first_constructed = true;
+ __node_traits::construct(__na, std::addressof(__h->__value_.__get_value().second));
+ __h.get_deleter().__second_constructed = true;
+ return __h;
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+_Tp& map<_Key, _Tp, _Compare, _Allocator>::operator[](const key_type& __k) {
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __tree_.__find_equal(__parent, __k);
+ __node_pointer __r = static_cast<__node_pointer>(__child);
+ if (__child == nullptr) {
+ __node_holder __h = __construct_node_with_key(__k);
+ __tree_.__insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
+ __r = __h.release();
+ }
+ return __r->__value_.__get_value().second;
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+_Tp& map<_Key, _Tp, _Compare, _Allocator>::at(const key_type& __k) {
+ __parent_pointer __parent;
+ __node_base_pointer& __child = __tree_.__find_equal(__parent, __k);
+ if (__child == nullptr)
+ __throw_out_of_range("map::at: key not found");
+ return static_cast<__node_pointer>(__child)->__value_.__get_value().second;
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+const _Tp& map<_Key, _Tp, _Compare, _Allocator>::at(const key_type& __k) const {
+ __parent_pointer __parent;
+ __node_base_pointer __child = __tree_.__find_equal(__parent, __k);
+ if (__child == nullptr)
+ __throw_out_of_range("map::at: key not found");
+ return static_cast<__node_pointer>(__child)->__value_.__get_value().second;
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const map<_Key, _Tp, _Compare, _Allocator>& __x, const map<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return __x.size() == __y.size() && std::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const map<_Key, _Tp, _Compare, _Allocator>& __x, const map<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const map<_Key, _Tp, _Compare, _Allocator>& __x, const map<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const map<_Key, _Tp, _Compare, _Allocator>& __x, const map<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return __y < __x;
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const map<_Key, _Tp, _Compare, _Allocator>& __x, const map<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const map<_Key, _Tp, _Compare, _Allocator>& __x, const map<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return !(__y < __x);
+}
+
+#else // #if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __synth_three_way_result<pair<const _Key, _Tp>>
+operator<=>(const map<_Key, _Tp, _Compare, _Allocator>& __x, const map<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return std::lexicographical_compare_three_way(__x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+}
+
+#endif // #if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(map<_Key, _Tp, _Compare, _Allocator>& __x, map<_Key, _Tp, _Compare, _Allocator>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Key, class _Tp, class _Compare, class _Allocator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename map<_Key, _Tp, _Compare, _Allocator>::size_type
+erase_if(map<_Key, _Tp, _Compare, _Allocator>& __c, _Predicate __pred) {
+ return std::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+template <class _Key, class _Tp, class _Compare = less<_Key>, class _Allocator = allocator<pair<const _Key, _Tp> > >
+class _LIBCPP_TEMPLATE_VIS multimap {
+public:
+ // types:
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef __type_identity_t<_Compare> key_compare;
+ typedef __type_identity_t<_Allocator> allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+ static_assert(is_same<typename allocator_type::value_type, value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+ class _LIBCPP_TEMPLATE_VIS value_compare : public __binary_function<value_type, value_type, bool> {
+ friend class multimap;
+
+ protected:
+ key_compare comp;
+
+ _LIBCPP_HIDE_FROM_ABI value_compare(key_compare __c) : comp(__c) {}
+
+ public:
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const value_type& __x, const value_type& __y) const {
+ return comp(__x.first, __y.first);
+ }
+ };
+
+private:
+ typedef std::__value_type<key_type, mapped_type> __value_type;
+ typedef __map_value_compare<key_type, __value_type, key_compare> __vc;
+ typedef __rebind_alloc<allocator_traits<allocator_type>, __value_type> __allocator_type;
+ typedef __tree<__value_type, __vc, __allocator_type> __base;
+ typedef typename __base::__node_traits __node_traits;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+ __base __tree_;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+ typedef typename __alloc_traits::size_type size_type;
+ typedef typename __alloc_traits::difference_type difference_type;
+ typedef __map_iterator<typename __base::iterator> iterator;
+ typedef __map_const_iterator<typename __base::const_iterator> const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+#if _LIBCPP_STD_VER >= 17
+ typedef __map_node_handle<typename __base::__node, allocator_type> node_type;
+#endif
+
+ template <class _Key2, class _Value2, class _Comp2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS map;
+ template <class _Key2, class _Value2, class _Comp2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS multimap;
+
+ _LIBCPP_HIDE_FROM_ABI multimap() _NOEXCEPT_(
+ is_nothrow_default_constructible<allocator_type>::value&& is_nothrow_default_constructible<key_compare>::value&&
+ is_nothrow_copy_constructible<key_compare>::value)
+ : __tree_(__vc(key_compare())) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit multimap(const key_compare& __comp) _NOEXCEPT_(
+ is_nothrow_default_constructible<allocator_type>::value&& is_nothrow_copy_constructible<key_compare>::value)
+ : __tree_(__vc(__comp)) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit multimap(const key_compare& __comp, const allocator_type& __a)
+ : __tree_(__vc(__comp), typename __base::allocator_type(__a)) {}
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI multimap(_InputIterator __f, _InputIterator __l, const key_compare& __comp = key_compare())
+ : __tree_(__vc(__comp)) {
+ insert(__f, __l);
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ multimap(_InputIterator __f, _InputIterator __l, const key_compare& __comp, const allocator_type& __a)
+ : __tree_(__vc(__comp), typename __base::allocator_type(__a)) {
+ insert(__f, __l);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI
+ multimap(from_range_t,
+ _Range&& __range,
+ const key_compare& __comp = key_compare(),
+ const allocator_type& __a = allocator_type())
+ : __tree_(__vc(__comp), typename __base::allocator_type(__a)) {
+ insert_range(std::forward<_Range>(__range));
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI multimap(_InputIterator __f, _InputIterator __l, const allocator_type& __a)
+ : multimap(__f, __l, key_compare(), __a) {}
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI multimap(from_range_t, _Range&& __range, const allocator_type& __a)
+ : multimap(from_range, std::forward<_Range>(__range), key_compare(), __a) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI multimap(const multimap& __m)
+ : __tree_(__m.__tree_.value_comp(),
+ __alloc_traits::select_on_container_copy_construction(__m.__tree_.__alloc())) {
+ insert(__m.begin(), __m.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI multimap& operator=(const multimap& __m) {
+#ifndef _LIBCPP_CXX03_LANG
+ __tree_ = __m.__tree_;
+#else
+ if (this != std::addressof(__m)) {
+ __tree_.clear();
+ __tree_.value_comp() = __m.__tree_.value_comp();
+ __tree_.__copy_assign_alloc(__m.__tree_);
+ insert(__m.begin(), __m.end());
+ }
+#endif
+ return *this;
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI multimap(multimap&& __m) noexcept(is_nothrow_move_constructible<__base>::value)
+ : __tree_(std::move(__m.__tree_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI multimap(multimap&& __m, const allocator_type& __a);
+
+ _LIBCPP_HIDE_FROM_ABI multimap& operator=(multimap&& __m) noexcept(is_nothrow_move_assignable<__base>::value) {
+ __tree_ = std::move(__m.__tree_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI multimap(initializer_list<value_type> __il, const key_compare& __comp = key_compare())
+ : __tree_(__vc(__comp)) {
+ insert(__il.begin(), __il.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI
+ multimap(initializer_list<value_type> __il, const key_compare& __comp, const allocator_type& __a)
+ : __tree_(__vc(__comp), typename __base::allocator_type(__a)) {
+ insert(__il.begin(), __il.end());
+ }
+
+# if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI multimap(initializer_list<value_type> __il, const allocator_type& __a)
+ : multimap(__il, key_compare(), __a) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI multimap& operator=(initializer_list<value_type> __il) {
+ __tree_.__assign_multi(__il.begin(), __il.end());
+ return *this;
+ }
+
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI explicit multimap(const allocator_type& __a) : __tree_(typename __base::allocator_type(__a)) {}
+
+ _LIBCPP_HIDE_FROM_ABI multimap(const multimap& __m, const allocator_type& __a)
+ : __tree_(__m.__tree_.value_comp(), typename __base::allocator_type(__a)) {
+ insert(__m.begin(), __m.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~multimap() { static_assert(sizeof(__diagnose_non_const_comparator<_Key, _Compare>()), ""); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __tree_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __tree_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __tree_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __tree_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() _NOEXCEPT { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const _NOEXCEPT { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() _NOEXCEPT { return reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const _NOEXCEPT { return const_reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const _NOEXCEPT { return rbegin(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __tree_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __tree_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __tree_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT { return allocator_type(__tree_.__alloc()); }
+ _LIBCPP_HIDE_FROM_ABI key_compare key_comp() const { return __tree_.value_comp().key_comp(); }
+ _LIBCPP_HIDE_FROM_ABI value_compare value_comp() const { return value_compare(__tree_.value_comp().key_comp()); }
+
+#ifndef _LIBCPP_CXX03_LANG
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace(_Args&&... __args) {
+ return __tree_.__emplace_multi(std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator __p, _Args&&... __args) {
+ return __tree_.__emplace_hint_multi(__p.__i_, std::forward<_Args>(__args)...);
+ }
+
+ template <class _Pp, __enable_if_t<is_constructible<value_type, _Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(_Pp&& __p) {
+ return __tree_.__insert_multi(std::forward<_Pp>(__p));
+ }
+
+ template <class _Pp, __enable_if_t<is_constructible<value_type, _Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __pos, _Pp&& __p) {
+ return __tree_.__insert_multi(__pos.__i_, std::forward<_Pp>(__p));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(value_type&& __v) { return __tree_.__insert_multi(std::move(__v)); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __v) {
+ return __tree_.__insert_multi(__p.__i_, std::move(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const value_type& __v) { return __tree_.__insert_multi(__v); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __v) {
+ return __tree_.__insert_multi(__p.__i_, __v);
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __f, _InputIterator __l) {
+ for (const_iterator __e = cend(); __f != __l; ++__f)
+ __tree_.__insert_multi(__e.__i_, *__f);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ const_iterator __end = cend();
+ for (auto&& __element : __range) {
+ __tree_.__insert_multi(__end.__i_, std::forward<decltype(__element)>(__element));
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p) { return __tree_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(iterator __p) { return __tree_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __tree_.__erase_multi(__k); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __f, const_iterator __l) {
+ return __tree_.erase(__f.__i_, __l.__i_);
+ }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI iterator insert(node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to multimap::insert()");
+ return __tree_.template __node_handle_insert_multi<node_type>(std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to multimap::insert()");
+ return __tree_.template __node_handle_insert_multi<node_type>(__hint.__i_, std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(key_type const& __key) {
+ return __tree_.template __node_handle_extract<node_type>(__key);
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(const_iterator __it) {
+ return __tree_.template __node_handle_extract<node_type>(__it.__i_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(multimap<key_type, mapped_type, _Compare2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __tree_.__node_handle_merge_multi(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(multimap<key_type, mapped_type, _Compare2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __tree_.__node_handle_merge_multi(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(map<key_type, mapped_type, _Compare2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __tree_.__node_handle_merge_multi(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(map<key_type, mapped_type, _Compare2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __tree_.__node_handle_merge_multi(__source.__tree_);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __tree_.clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(multimap& __m) _NOEXCEPT_(__is_nothrow_swappable_v<__base>) {
+ __tree_.swap(__m.__tree_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __tree_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __tree_.find(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _K2& __k) {
+ return __tree_.find(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _K2& __k) const {
+ return __tree_.find(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __tree_.__count_multi(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _K2& __k) const {
+ return __tree_.__count_multi(__k);
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __k) const { return find(__k) != end(); }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _K2& __k) const {
+ return find(__k) != end();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const key_type& __k) { return __tree_.lower_bound(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const key_type& __k) const { return __tree_.lower_bound(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const _K2& __k) {
+ return __tree_.lower_bound(__k);
+ }
+
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const _K2& __k) const {
+ return __tree_.lower_bound(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const key_type& __k) { return __tree_.upper_bound(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const key_type& __k) const { return __tree_.upper_bound(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const _K2& __k) {
+ return __tree_.upper_bound(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const _K2& __k) const {
+ return __tree_.upper_bound(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __tree_.__equal_range_multi(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __tree_.__equal_range_multi(__k);
+ }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _K2& __k) {
+ return __tree_.__equal_range_multi(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _K2& __k) const {
+ return __tree_.__equal_range_multi(__k);
+ }
+#endif
+
+private:
+ typedef typename __base::__node __node;
+ typedef typename __base::__node_allocator __node_allocator;
+ typedef typename __base::__node_pointer __node_pointer;
+
+ typedef __map_node_destructor<__node_allocator> _Dp;
+ typedef unique_ptr<__node, _Dp> __node_holder;
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Compare = less<__iter_key_type<_InputIterator>>,
+ class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value, void>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multimap(_InputIterator, _InputIterator, _Compare = _Compare(), _Allocator = _Allocator())
+ -> multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Compare, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Compare = less<__range_key_type<_Range>>,
+ class _Allocator = allocator<__range_to_alloc_type<_Range>>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multimap(from_range_t, _Range&&, _Compare = _Compare(), _Allocator = _Allocator())
+ -> multimap<__range_key_type<_Range>, __range_mapped_type<_Range>, _Compare, _Allocator>;
+# endif
+
+template <class _Key,
+ class _Tp,
+ class _Compare = less<remove_const_t<_Key>>,
+ class _Allocator = allocator<pair<const _Key, _Tp>>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multimap(initializer_list<pair<_Key, _Tp>>,
+ _Compare = _Compare(),
+ _Allocator = _Allocator()) -> multimap<remove_const_t<_Key>, _Tp, _Compare, _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multimap(_InputIterator, _InputIterator, _Allocator)
+ -> multimap<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ less<__iter_key_type<_InputIterator>>,
+ _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multimap(from_range_t, _Range&&, _Allocator)
+ -> multimap<__range_key_type<_Range>, __range_mapped_type<_Range>, less<__range_key_type<_Range>>, _Allocator>;
+# endif
+
+template <class _Key, class _Tp, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multimap(initializer_list<pair<_Key, _Tp>>,
+ _Allocator) -> multimap<remove_const_t<_Key>, _Tp, less<remove_const_t<_Key>>, _Allocator>;
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+multimap<_Key, _Tp, _Compare, _Allocator>::multimap(multimap&& __m, const allocator_type& __a)
+ : __tree_(std::move(__m.__tree_), typename __base::allocator_type(__a)) {
+ if (__a != __m.get_allocator()) {
+ const_iterator __e = cend();
+ while (!__m.empty())
+ __tree_.__insert_multi(__e.__i_, std::move(__m.__tree_.remove(__m.begin().__i_)->__value_.__move()));
+ }
+}
+#endif
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const multimap<_Key, _Tp, _Compare, _Allocator>& __x, const multimap<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return __x.size() == __y.size() && std::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const multimap<_Key, _Tp, _Compare, _Allocator>& __x, const multimap<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const multimap<_Key, _Tp, _Compare, _Allocator>& __x, const multimap<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const multimap<_Key, _Tp, _Compare, _Allocator>& __x, const multimap<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return __y < __x;
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const multimap<_Key, _Tp, _Compare, _Allocator>& __x, const multimap<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const multimap<_Key, _Tp, _Compare, _Allocator>& __x, const multimap<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return !(__y < __x);
+}
+
+#else // #if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __synth_three_way_result<pair<const _Key, _Tp>>
+operator<=>(const multimap<_Key, _Tp, _Compare, _Allocator>& __x,
+ const multimap<_Key, _Tp, _Compare, _Allocator>& __y) {
+ return std::lexicographical_compare_three_way(__x.begin(), __x.end(), __y.begin(), __y.end(), __synth_three_way);
+}
+
+#endif // #if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(multimap<_Key, _Tp, _Compare, _Allocator>& __x, multimap<_Key, _Tp, _Compare, _Allocator>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Key, class _Tp, class _Compare, class _Allocator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename multimap<_Key, _Tp, _Compare, _Allocator>::size_type
+erase_if(multimap<_Key, _Tp, _Compare, _Allocator>& __c, _Predicate __pred) {
+ return std::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _KeyT, class _ValueT, class _CompareT = std::less<_KeyT>>
+using map _LIBCPP_AVAILABILITY_PMR =
+ std::map<_KeyT, _ValueT, _CompareT, polymorphic_allocator<std::pair<const _KeyT, _ValueT>>>;
+
+template <class _KeyT, class _ValueT, class _CompareT = std::less<_KeyT>>
+using multimap _LIBCPP_AVAILABILITY_PMR =
+ std::multimap<_KeyT, _ValueT, _CompareT, polymorphic_allocator<std::pair<const _KeyT, _ValueT>>>;
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <cstdlib>
+# include <functional>
+# include <iterator>
+# include <type_traits>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_MAP
diff --git a/libcxx/include/__cxx03/math.h b/libcxx/include/__cxx03/math.h
new file mode 100644
index 00000000000000..4e6304a7539849
--- /dev/null
+++ b/libcxx/include/__cxx03/math.h
@@ -0,0 +1,520 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_MATH_H
+# define _LIBCPP_MATH_H
+
+/*
+ math.h synopsis
+
+Macros:
+
+ HUGE_VAL
+ HUGE_VALF // C99
+ HUGE_VALL // C99
+ INFINITY // C99
+ NAN // C99
+ FP_INFINITE // C99
+ FP_NAN // C99
+ FP_NORMAL // C99
+ FP_SUBNORMAL // C99
+ FP_ZERO // C99
+ FP_FAST_FMA // C99
+ FP_FAST_FMAF // C99
+ FP_FAST_FMAL // C99
+ FP_ILOGB0 // C99
+ FP_ILOGBNAN // C99
+ MATH_ERRNO // C99
+ MATH_ERREXCEPT // C99
+ math_errhandling // C99
+
+Types:
+
+ float_t // C99
+ double_t // C99
+
+// C90
+
+floating_point abs(floating_point x);
+
+floating_point acos (arithmetic x);
+float acosf(float x);
+long double acosl(long double x);
+
+floating_point asin (arithmetic x);
+float asinf(float x);
+long double asinl(long double x);
+
+floating_point atan (arithmetic x);
+float atanf(float x);
+long double atanl(long double x);
+
+floating_point atan2 (arithmetic y, arithmetic x);
+float atan2f(float y, float x);
+long double atan2l(long double y, long double x);
+
+floating_point ceil (arithmetic x);
+float ceilf(float x);
+long double ceill(long double x);
+
+floating_point cos (arithmetic x);
+float cosf(float x);
+long double cosl(long double x);
+
+floating_point cosh (arithmetic x);
+float coshf(float x);
+long double coshl(long double x);
+
+floating_point exp (arithmetic x);
+float expf(float x);
+long double expl(long double x);
+
+floating_point fabs (arithmetic x);
+float fabsf(float x);
+long double fabsl(long double x);
+
+floating_point floor (arithmetic x);
+float floorf(float x);
+long double floorl(long double x);
+
+floating_point fmod (arithmetic x, arithmetic y);
+float fmodf(float x, float y);
+long double fmodl(long double x, long double y);
+
+floating_point frexp (arithmetic value, int* exp);
+float frexpf(float value, int* exp);
+long double frexpl(long double value, int* exp);
+
+floating_point ldexp (arithmetic value, int exp);
+float ldexpf(float value, int exp);
+long double ldexpl(long double value, int exp);
+
+floating_point log (arithmetic x);
+float logf(float x);
+long double logl(long double x);
+
+floating_point log10 (arithmetic x);
+float log10f(float x);
+long double log10l(long double x);
+
+floating_point modf (floating_point value, floating_point* iptr);
+float modff(float value, float* iptr);
+long double modfl(long double value, long double* iptr);
+
+floating_point pow (arithmetic x, arithmetic y);
+float powf(float x, float y);
+long double powl(long double x, long double y);
+
+floating_point sin (arithmetic x);
+float sinf(float x);
+long double sinl(long double x);
+
+floating_point sinh (arithmetic x);
+float sinhf(float x);
+long double sinhl(long double x);
+
+floating_point sqrt (arithmetic x);
+float sqrtf(float x);
+long double sqrtl(long double x);
+
+floating_point tan (arithmetic x);
+float tanf(float x);
+long double tanl(long double x);
+
+floating_point tanh (arithmetic x);
+float tanhf(float x);
+long double tanhl(long double x);
+
+// C99
+
+bool signbit(arithmetic x);
+
+int fpclassify(arithmetic x);
+
+bool isfinite(arithmetic x);
+bool isinf(arithmetic x);
+bool isnan(arithmetic x);
+bool isnormal(arithmetic x);
+
+bool isgreater(arithmetic x, arithmetic y);
+bool isgreaterequal(arithmetic x, arithmetic y);
+bool isless(arithmetic x, arithmetic y);
+bool islessequal(arithmetic x, arithmetic y);
+bool islessgreater(arithmetic x, arithmetic y);
+bool isunordered(arithmetic x, arithmetic y);
+
+floating_point acosh (arithmetic x);
+float acoshf(float x);
+long double acoshl(long double x);
+
+floating_point asinh (arithmetic x);
+float asinhf(float x);
+long double asinhl(long double x);
+
+floating_point atanh (arithmetic x);
+float atanhf(float x);
+long double atanhl(long double x);
+
+floating_point cbrt (arithmetic x);
+float cbrtf(float x);
+long double cbrtl(long double x);
+
+floating_point copysign (arithmetic x, arithmetic y);
+float copysignf(float x, float y);
+long double copysignl(long double x, long double y);
+
+floating_point erf (arithmetic x);
+float erff(float x);
+long double erfl(long double x);
+
+floating_point erfc (arithmetic x);
+float erfcf(float x);
+long double erfcl(long double x);
+
+floating_point exp2 (arithmetic x);
+float exp2f(float x);
+long double exp2l(long double x);
+
+floating_point expm1 (arithmetic x);
+float expm1f(float x);
+long double expm1l(long double x);
+
+floating_point fdim (arithmetic x, arithmetic y);
+float fdimf(float x, float y);
+long double fdiml(long double x, long double y);
+
+floating_point fma (arithmetic x, arithmetic y, arithmetic z);
+float fmaf(float x, float y, float z);
+long double fmal(long double x, long double y, long double z);
+
+floating_point fmax (arithmetic x, arithmetic y);
+float fmaxf(float x, float y);
+long double fmaxl(long double x, long double y);
+
+floating_point fmin (arithmetic x, arithmetic y);
+float fminf(float x, float y);
+long double fminl(long double x, long double y);
+
+floating_point hypot (arithmetic x, arithmetic y);
+float hypotf(float x, float y);
+long double hypotl(long double x, long double y);
+
+int ilogb (arithmetic x);
+int ilogbf(float x);
+int ilogbl(long double x);
+
+floating_point lgamma (arithmetic x);
+float lgammaf(float x);
+long double lgammal(long double x);
+
+long long llrint (arithmetic x);
+long long llrintf(float x);
+long long llrintl(long double x);
+
+long long llround (arithmetic x);
+long long llroundf(float x);
+long long llroundl(long double x);
+
+floating_point log1p (arithmetic x);
+float log1pf(float x);
+long double log1pl(long double x);
+
+floating_point log2 (arithmetic x);
+float log2f(float x);
+long double log2l(long double x);
+
+floating_point logb (arithmetic x);
+float logbf(float x);
+long double logbl(long double x);
+
+long lrint (arithmetic x);
+long lrintf(float x);
+long lrintl(long double x);
+
+long lround (arithmetic x);
+long lroundf(float x);
+long lroundl(long double x);
+
+double nan (const char* str);
+float nanf(const char* str);
+long double nanl(const char* str);
+
+floating_point nearbyint (arithmetic x);
+float nearbyintf(float x);
+long double nearbyintl(long double x);
+
+floating_point nextafter (arithmetic x, arithmetic y);
+float nextafterf(float x, float y);
+long double nextafterl(long double x, long double y);
+
+floating_point nexttoward (arithmetic x, long double y);
+float nexttowardf(float x, long double y);
+long double nexttowardl(long double x, long double y);
+
+floating_point remainder (arithmetic x, arithmetic y);
+float remainderf(float x, float y);
+long double remainderl(long double x, long double y);
+
+floating_point remquo (arithmetic x, arithmetic y, int* pquo);
+float remquof(float x, float y, int* pquo);
+long double remquol(long double x, long double y, int* pquo);
+
+floating_point rint (arithmetic x);
+float rintf(float x);
+long double rintl(long double x);
+
+floating_point round (arithmetic x);
+float roundf(float x);
+long double roundl(long double x);
+
+floating_point scalbln (arithmetic x, long ex);
+float scalblnf(float x, long ex);
+long double scalblnl(long double x, long ex);
+
+floating_point scalbn (arithmetic x, int ex);
+float scalbnf(float x, int ex);
+long double scalbnl(long double x, int ex);
+
+floating_point tgamma (arithmetic x);
+float tgammaf(float x);
+long double tgammal(long double x);
+
+floating_point trunc (arithmetic x);
+float truncf(float x);
+long double truncl(long double x);
+
+*/
+
+# include <__config>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+# if __has_include_next(<math.h>)
+# include_next <math.h>
+# endif
+
+# ifdef __cplusplus
+
+// We support including .h headers inside 'extern "C"' contexts, so switch
+// back to C++ linkage before including these C++ headers.
+extern "C++" {
+
+# ifdef fpclassify
+# undef fpclassify
+# endif
+
+# ifdef signbit
+# undef signbit
+# endif
+
+# ifdef isfinite
+# undef isfinite
+# endif
+
+# ifdef isinf
+# undef isinf
+# endif
+
+# ifdef isnan
+# undef isnan
+# endif
+
+# ifdef isnormal
+# undef isnormal
+# endif
+
+# ifdef isgreater
+# undef isgreater
+# endif
+
+# ifdef isgreaterequal
+# undef isgreaterequal
+# endif
+
+# ifdef isless
+# undef isless
+# endif
+
+# ifdef islessequal
+# undef islessequal
+# endif
+
+# ifdef islessgreater
+# undef islessgreater
+# endif
+
+# ifdef isunordered
+# undef isunordered
+# endif
+
+# include <__math/abs.h>
+# include <__math/copysign.h>
+# include <__math/error_functions.h>
+# include <__math/exponential_functions.h>
+# include <__math/fdim.h>
+# include <__math/fma.h>
+# include <__math/gamma.h>
+# include <__math/hyperbolic_functions.h>
+# include <__math/hypot.h>
+# include <__math/inverse_hyperbolic_functions.h>
+# include <__math/inverse_trigonometric_functions.h>
+# include <__math/logarithms.h>
+# include <__math/min_max.h>
+# include <__math/modulo.h>
+# include <__math/remainder.h>
+# include <__math/roots.h>
+# include <__math/rounding_functions.h>
+# include <__math/traits.h>
+# include <__math/trigonometric_functions.h>
+# include <__type_traits/enable_if.h>
+# include <__type_traits/is_floating_point.h>
+# include <__type_traits/is_integral.h>
+# include <stdlib.h>
+
+// fpclassify relies on implementation-defined constants, so we can't move it to a detail header
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __math {
+
+// fpclassify
+
+// template on non-double overloads to make them weaker than same overloads from MSVC runtime
+template <class = int>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI int fpclassify(float __x) _NOEXCEPT {
+ return __builtin_fpclassify(FP_NAN, FP_INFINITE, FP_NORMAL, FP_SUBNORMAL, FP_ZERO, __x);
+}
+
+template <class = int>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI int fpclassify(double __x) _NOEXCEPT {
+ return __builtin_fpclassify(FP_NAN, FP_INFINITE, FP_NORMAL, FP_SUBNORMAL, FP_ZERO, __x);
+}
+
+template <class = int>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI int fpclassify(long double __x) _NOEXCEPT {
+ return __builtin_fpclassify(FP_NAN, FP_INFINITE, FP_NORMAL, FP_SUBNORMAL, FP_ZERO, __x);
+}
+
+template <class _A1, std::__enable_if_t<std::is_integral<_A1>::value, int> = 0>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI int fpclassify(_A1 __x) _NOEXCEPT {
+ return __x == 0 ? FP_ZERO : FP_NORMAL;
+}
+
+} // namespace __math
+
+_LIBCPP_END_NAMESPACE_STD
+
+using std::__math::fpclassify;
+using std::__math::signbit;
+
+// The MSVC runtime already provides these functions as templates
+# ifndef _LIBCPP_MSVCRT
+using std::__math::isfinite;
+using std::__math::isgreater;
+using std::__math::isgreaterequal;
+using std::__math::isinf;
+using std::__math::isless;
+using std::__math::islessequal;
+using std::__math::islessgreater;
+using std::__math::isnan;
+using std::__math::isnormal;
+using std::__math::isunordered;
+# endif // _LIBCPP_MSVCRT
+
+// abs
+//
+// handled in stdlib.h
+
+// div
+//
+// handled in stdlib.h
+
+// We have to provide double overloads for <math.h> to work on platforms that don't provide the full set of math
+// functions. To make the overload set work with multiple functions that take the same arguments, we make our overloads
+// templates. Functions are preferred over function templates during overload resolution, which means that our overload
+// will only be selected when the C library doesn't provide one.
+
+using std::__math::acos;
+using std::__math::acosh;
+using std::__math::asin;
+using std::__math::asinh;
+using std::__math::atan;
+using std::__math::atan2;
+using std::__math::atanh;
+using std::__math::cbrt;
+using std::__math::ceil;
+using std::__math::copysign;
+using std::__math::cos;
+using std::__math::cosh;
+using std::__math::erf;
+using std::__math::erfc;
+using std::__math::exp;
+using std::__math::exp2;
+using std::__math::expm1;
+using std::__math::fabs;
+using std::__math::fdim;
+using std::__math::floor;
+using std::__math::fma;
+using std::__math::fmax;
+using std::__math::fmin;
+using std::__math::fmod;
+using std::__math::frexp;
+using std::__math::hypot;
+using std::__math::ilogb;
+using std::__math::ldexp;
+using std::__math::lgamma;
+using std::__math::llrint;
+using std::__math::llround;
+using std::__math::log;
+using std::__math::log10;
+using std::__math::log1p;
+using std::__math::log2;
+using std::__math::logb;
+using std::__math::lrint;
+using std::__math::lround;
+using std::__math::modf;
+using std::__math::nearbyint;
+using std::__math::nextafter;
+using std::__math::nexttoward;
+using std::__math::pow;
+using std::__math::remainder;
+using std::__math::remquo;
+using std::__math::rint;
+using std::__math::round;
+using std::__math::scalbln;
+using std::__math::scalbn;
+using std::__math::signbit;
+using std::__math::sin;
+using std::__math::sinh;
+using std::__math::sqrt;
+using std::__math::tan;
+using std::__math::tanh;
+using std::__math::tgamma;
+using std::__math::trunc;
+
+} // extern "C++"
+
+# endif // __cplusplus
+
+#else // _LIBCPP_MATH_H
+
+// This include lives outside the header guard in order to support an MSVC
+// extension which allows users to do:
+//
+// #define _USE_MATH_DEFINES
+// #include <math.h>
+//
+// and receive the definitions of mathematical constants, even if <math.h>
+// has previously been included.
+# if defined(_LIBCPP_MSVCRT) && defined(_USE_MATH_DEFINES)
+# include_next <math.h>
+# endif
+
+#endif // _LIBCPP_MATH_H
diff --git a/libcxx/include/__cxx03/mdspan b/libcxx/include/__cxx03/mdspan
new file mode 100644
index 00000000000000..29190e4a9953ed
--- /dev/null
+++ b/libcxx/include/__cxx03/mdspan
@@ -0,0 +1,438 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+/*
+
+// Overall mdspan synopsis
+
+namespace std {
+ // [mdspan.extents], class template extents
+ template<class IndexType, size_t... Extents>
+ class extents;
+
+ // [mdspan.extents.dextents], alias template dextents
+ template<class IndexType, size_t Rank>
+ using dextents = see below;
+
+ // [mdspan.extents.dims], alias template dims
+ template<size_t Rank, class IndexType = size_t>
+ using dims = see below; // since C++26
+
+ // [mdspan.layout], layout mapping
+ struct layout_left;
+ struct layout_right;
+ struct layout_stride;
+
+ // [mdspan.accessor.default], class template default_accessor
+ template<class ElementType>
+ class default_accessor;
+
+ // [mdspan.mdspan], class template mdspan
+ template<class ElementType, class Extents, class LayoutPolicy = layout_right,
+ class AccessorPolicy = default_accessor<ElementType>>
+ class mdspan; // not implemented yet
+}
+
+// extents synopsis
+
+namespace std {
+ template<class _IndexType, size_t... _Extents>
+ class extents {
+ public:
+ using index_type = _IndexType;
+ using size_type = make_unsigned_t<index_type>;
+ using rank_type = size_t;
+
+ // [mdspan.extents.obs], observers of the multidimensional index space
+ static constexpr rank_type rank() noexcept { return sizeof...(_Extents); }
+ static constexpr rank_type rank_dynamic() noexcept { return dynamic-index(rank()); }
+ static constexpr size_t static_extent(rank_type) noexcept;
+ constexpr index_type extent(rank_type) const noexcept;
+
+ // [mdspan.extents.cons], constructors
+ constexpr extents() noexcept = default;
+
+ template<class _OtherIndexType, size_t... _OtherExtents>
+ constexpr explicit(see below)
+ extents(const extents<_OtherIndexType, _OtherExtents...>&) noexcept;
+ template<class... _OtherIndexTypes>
+ constexpr explicit extents(_OtherIndexTypes...) noexcept;
+ template<class _OtherIndexType, size_t N>
+ constexpr explicit(N != rank_dynamic())
+ extents(span<_OtherIndexType, N>) noexcept;
+ template<class _OtherIndexType, size_t N>
+ constexpr explicit(N != rank_dynamic())
+ extents(const array<_OtherIndexType, N>&) noexcept;
+
+ // [mdspan.extents.cmp], comparison operators
+ template<class _OtherIndexType, size_t... _OtherExtents>
+ friend constexpr bool operator==(const extents&,
+ const extents<_OtherIndexType, _OtherExtents...>&) noexcept;
+
+ private:
+ // libcxx note: we do not use an array here, but we need to preserve the as-if behavior
+ // for example the default constructor must zero initialize dynamic extents
+ array<index_type, rank_dynamic()> dynamic-extents{}; // exposition only
+ };
+
+ template<class... Integrals>
+ explicit extents(Integrals...)
+ -> see below;
+}
+
+// layout_left synopsis
+
+namespace std {
+ template<class Extents>
+ class layout_left::mapping {
+ public:
+ using extents_type = Extents;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using layout_type = layout_left;
+
+ // [mdspan.layout.right.cons], constructors
+ constexpr mapping() noexcept = default;
+ constexpr mapping(const mapping&) noexcept = default;
+ constexpr mapping(const extents_type&) noexcept;
+ template<class OtherExtents>
+ constexpr explicit(!is_convertible_v<OtherExtents, extents_type>)
+ mapping(const mapping<OtherExtents>&) noexcept;
+ template<class OtherExtents>
+ constexpr explicit(!is_convertible_v<OtherExtents, extents_type>)
+ mapping(const layout_right::mapping<OtherExtents>&) noexcept;
+ template<class OtherExtents>
+ constexpr explicit(extents_type::rank() > 0)
+ mapping(const layout_stride::mapping<OtherExtents>&) noexcept;
+
+ constexpr mapping& operator=(const mapping&) noexcept = default;
+
+ // [mdspan.layout.right.obs], observers
+ constexpr const extents_type& extents() const noexcept { return extents_; }
+
+ constexpr index_type required_span_size() const noexcept;
+
+ template<class... Indices>
+ constexpr index_type operator()(Indices...) const noexcept;
+
+ static constexpr bool is_always_unique() noexcept { return true; }
+ static constexpr bool is_always_exhaustive() noexcept { return true; }
+ static constexpr bool is_always_strided() noexcept { return true; }
+
+ static constexpr bool is_unique() noexcept { return true; }
+ static constexpr bool is_exhaustive() noexcept { return true; }
+ static constexpr bool is_strided() noexcept { return true; }
+
+ constexpr index_type stride(rank_type) const noexcept;
+
+ template<class OtherExtents>
+ friend constexpr bool operator==(const mapping&, const mapping<OtherExtents>&) noexcept;
+
+ private:
+ extents_type extents_{}; // exposition only
+ };
+}
+
+// layout_right synopsis
+
+namespace std {
+ template<class Extents>
+ class layout_right::mapping {
+ public:
+ using extents_type = Extents;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using layout_type = layout_right;
+
+ // [mdspan.layout.right.cons], constructors
+ constexpr mapping() noexcept = default;
+ constexpr mapping(const mapping&) noexcept = default;
+ constexpr mapping(const extents_type&) noexcept;
+ template<class OtherExtents>
+ constexpr explicit(!is_convertible_v<OtherExtents, extents_type>)
+ mapping(const mapping<OtherExtents>&) noexcept;
+ template<class OtherExtents>
+ constexpr explicit(!is_convertible_v<OtherExtents, extents_type>)
+ mapping(const layout_left::mapping<OtherExtents>&) noexcept;
+ template<class OtherExtents>
+ constexpr explicit(extents_type::rank() > 0)
+ mapping(const layout_stride::mapping<OtherExtents>&) noexcept;
+
+ constexpr mapping& operator=(const mapping&) noexcept = default;
+
+ // [mdspan.layout.right.obs], observers
+ constexpr const extents_type& extents() const noexcept { return extents_; }
+
+ constexpr index_type required_span_size() const noexcept;
+
+ template<class... Indices>
+ constexpr index_type operator()(Indices...) const noexcept;
+
+ static constexpr bool is_always_unique() noexcept { return true; }
+ static constexpr bool is_always_exhaustive() noexcept { return true; }
+ static constexpr bool is_always_strided() noexcept { return true; }
+
+ static constexpr bool is_unique() noexcept { return true; }
+ static constexpr bool is_exhaustive() noexcept { return true; }
+ static constexpr bool is_strided() noexcept { return true; }
+
+ constexpr index_type stride(rank_type) const noexcept;
+
+ template<class OtherExtents>
+ friend constexpr bool operator==(const mapping&, const mapping<OtherExtents>&) noexcept;
+
+ private:
+ extents_type extents_{}; // exposition only
+ };
+}
+
+// layout_stride synopsis
+
+namespace std {
+ template<class Extents>
+ class layout_stride::mapping {
+ public:
+ using extents_type = Extents;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using layout_type = layout_stride;
+
+ private:
+ static constexpr rank_type rank_ = extents_type::rank(); // exposition only
+
+ public:
+ // [mdspan.layout.stride.cons], constructors
+ constexpr mapping() noexcept;
+ constexpr mapping(const mapping&) noexcept = default;
+ template<class OtherIndexType>
+ constexpr mapping(const extents_type&, span<OtherIndexType, rank_>) noexcept;
+ template<class OtherIndexType>
+ constexpr mapping(const extents_type&, const array<OtherIndexType, rank_>&) noexcept;
+
+ template<class StridedLayoutMapping>
+ constexpr explicit(see below) mapping(const StridedLayoutMapping&) noexcept;
+
+ constexpr mapping& operator=(const mapping&) noexcept = default;
+
+ // [mdspan.layout.stride.obs], observers
+ constexpr const extents_type& extents() const noexcept { return extents_; }
+ constexpr array<index_type, rank_> strides() const noexcept { return strides_; }
+
+ constexpr index_type required_span_size() const noexcept;
+
+ template<class... Indices>
+ constexpr index_type operator()(Indices...) const noexcept;
+
+ static constexpr bool is_always_unique() noexcept { return true; }
+ static constexpr bool is_always_exhaustive() noexcept { return false; }
+ static constexpr bool is_always_strided() noexcept { return true; }
+
+ static constexpr bool is_unique() noexcept { return true; }
+ constexpr bool is_exhaustive() const noexcept;
+ static constexpr bool is_strided() noexcept { return true; }
+
+ constexpr index_type stride(rank_type i) const noexcept { return strides_[i]; }
+
+ template<class OtherMapping>
+ friend constexpr bool operator==(const mapping&, const OtherMapping&) noexcept;
+
+ private:
+ extents_type extents_{}; // exposition only
+ array<index_type, rank_> strides_{}; // exposition only
+ };
+}
+
+// default_accessor synopsis
+
+namespace std {
+ template<class ElementType>
+ struct default_accessor {
+ using offset_policy = default_accessor;
+ using element_type = ElementType;
+ using reference = ElementType&;
+ using data_handle_type = ElementType*;
+
+ constexpr default_accessor() noexcept = default;
+ template<class OtherElementType>
+ constexpr default_accessor(default_accessor<OtherElementType>) noexcept;
+ constexpr reference access(data_handle_type p, size_t i) const noexcept;
+ constexpr data_handle_type offset(data_handle_type p, size_t i) const noexcept;
+ };
+}
+
+// mdspan synopsis
+
+namespace std {
+ template<class ElementType, class Extents, class LayoutPolicy = layout_right,
+ class AccessorPolicy = default_accessor<ElementType>>
+ class mdspan {
+ public:
+ using extents_type = Extents;
+ using layout_type = LayoutPolicy;
+ using accessor_type = AccessorPolicy;
+ using mapping_type = typename layout_type::template mapping<extents_type>;
+ using element_type = ElementType;
+ using value_type = remove_cv_t<element_type>;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using data_handle_type = typename accessor_type::data_handle_type;
+ using reference = typename accessor_type::reference;
+
+ static constexpr rank_type rank() noexcept { return extents_type::rank(); }
+ static constexpr rank_type rank_dynamic() noexcept { return extents_type::rank_dynamic(); }
+ static constexpr size_t static_extent(rank_type r) noexcept
+ { return extents_type::static_extent(r); }
+ constexpr index_type extent(rank_type r) const noexcept { return extents().extent(r); }
+
+ // [mdspan.mdspan.cons], constructors
+ constexpr mdspan();
+ constexpr mdspan(const mdspan& rhs) = default;
+ constexpr mdspan(mdspan&& rhs) = default;
+
+ template<class... OtherIndexTypes>
+ constexpr explicit mdspan(data_handle_type ptr, OtherIndexTypes... exts);
+ template<class OtherIndexType, size_t N>
+ constexpr explicit(N != rank_dynamic())
+ mdspan(data_handle_type p, span<OtherIndexType, N> exts);
+ template<class OtherIndexType, size_t N>
+ constexpr explicit(N != rank_dynamic())
+ mdspan(data_handle_type p, const array<OtherIndexType, N>& exts);
+ constexpr mdspan(data_handle_type p, const extents_type& ext);
+ constexpr mdspan(data_handle_type p, const mapping_type& m);
+ constexpr mdspan(data_handle_type p, const mapping_type& m, const accessor_type& a);
+
+ template<class OtherElementType, class OtherExtents,
+ class OtherLayoutPolicy, class OtherAccessorPolicy>
+ constexpr explicit(see below)
+ mdspan(const mdspan<OtherElementType, OtherExtents,
+ OtherLayoutPolicy, OtherAccessorPolicy>& other);
+
+ constexpr mdspan& operator=(const mdspan& rhs) = default;
+ constexpr mdspan& operator=(mdspan&& rhs) = default;
+
+ // [mdspan.mdspan.members], members
+ template<class... OtherIndexTypes>
+ constexpr reference operator[](OtherIndexTypes... indices) const;
+ template<class OtherIndexType>
+ constexpr reference operator[](span<OtherIndexType, rank()> indices) const;
+ template<class OtherIndexType>
+ constexpr reference operator[](const array<OtherIndexType, rank()>& indices) const;
+
+ constexpr size_type size() const noexcept;
+ [[nodiscard]] constexpr bool empty() const noexcept;
+
+ friend constexpr void swap(mdspan& x, mdspan& y) noexcept;
+
+ constexpr const extents_type& extents() const noexcept { return map_.extents(); }
+ constexpr const data_handle_type& data_handle() const noexcept { return ptr_; }
+ constexpr const mapping_type& mapping() const noexcept { return map_; }
+ constexpr const accessor_type& accessor() const noexcept { return acc_; }
+
+ // per LWG-4021 "mdspan::is_always_meow() should be noexcept"
+ static constexpr bool is_always_unique() noexcept
+ { return mapping_type::is_always_unique(); }
+ static constexpr bool is_always_exhaustive() noexcept
+ { return mapping_type::is_always_exhaustive(); }
+ static constexpr bool is_always_strided() noexcept
+ { return mapping_type::is_always_strided(); }
+
+ constexpr bool is_unique() const
+ { return map_.is_unique(); }
+ constexpr bool is_exhaustive() const
+ { return map_.is_exhaustive(); }
+ constexpr bool is_strided() const
+ { return map_.is_strided(); }
+ constexpr index_type stride(rank_type r) const
+ { return map_.stride(r); }
+
+ private:
+ accessor_type acc_; // exposition only
+ mapping_type map_; // exposition only
+ data_handle_type ptr_; // exposition only
+ };
+
+ template<class CArray>
+ requires(is_array_v<CArray> && rank_v<CArray> == 1)
+ mdspan(CArray&)
+ -> mdspan<remove_all_extents_t<CArray>, extents<size_t, extent_v<CArray, 0>>>;
+
+ template<class Pointer>
+ requires(is_pointer_v<remove_reference_t<Pointer>>)
+ mdspan(Pointer&&)
+ -> mdspan<remove_pointer_t<remove_reference_t<Pointer>>, extents<size_t>>;
+
+ template<class ElementType, class... Integrals>
+ requires((is_convertible_v<Integrals, size_t> && ...) && sizeof...(Integrals) > 0)
+ explicit mdspan(ElementType*, Integrals...)
+ -> mdspan<ElementType, dextents<size_t, sizeof...(Integrals)>>; // until C++26
+ template<class ElementType, class... Integrals>
+ requires((is_convertible_v<Integrals, size_t> && ...) && sizeof...(Integrals) > 0)
+ explicit mdspan(ElementType*, Integrals...)
+ -> mdspan<ElementType, extents<size_t, maybe-static-ext<Integrals>...>>; // since C++26
+
+ template<class ElementType, class OtherIndexType, size_t N>
+ mdspan(ElementType*, span<OtherIndexType, N>)
+ -> mdspan<ElementType, dextents<size_t, N>>;
+
+ template<class ElementType, class OtherIndexType, size_t N>
+ mdspan(ElementType*, const array<OtherIndexType, N>&)
+ -> mdspan<ElementType, dextents<size_t, N>>;
+
+ template<class ElementType, class IndexType, size_t... ExtentsPack>
+ mdspan(ElementType*, const extents<IndexType, ExtentsPack...>&)
+ -> mdspan<ElementType, extents<IndexType, ExtentsPack...>>;
+
+ template<class ElementType, class MappingType>
+ mdspan(ElementType*, const MappingType&)
+ -> mdspan<ElementType, typename MappingType::extents_type,
+ typename MappingType::layout_type>;
+
+ template<class MappingType, class AccessorType>
+ mdspan(const typename AccessorType::data_handle_type&, const MappingType&,
+ const AccessorType&)
+ -> mdspan<typename AccessorType::element_type, typename MappingType::extents_type,
+ typename MappingType::layout_type, AccessorType>;
+}
+*/
+
+#ifndef _LIBCPP_MDSPAN
+#define _LIBCPP_MDSPAN
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 23
+# include <__fwd/mdspan.h>
+# include <__mdspan/default_accessor.h>
+# include <__mdspan/extents.h>
+# include <__mdspan/layout_left.h>
+# include <__mdspan/layout_right.h>
+# include <__mdspan/layout_stride.h>
+# include <__mdspan/mdspan.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <array>
+# include <cinttypes>
+# include <concepts>
+# include <cstddef>
+# include <limits>
+# include <span>
+#endif
+
+#endif // _LIBCPP_MDSPAN
diff --git a/libcxx/include/__cxx03/memory b/libcxx/include/__cxx03/memory
new file mode 100644
index 00000000000000..b940a32c3ebe6c
--- /dev/null
+++ b/libcxx/include/__cxx03/memory
@@ -0,0 +1,998 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_MEMORY
+#define _LIBCPP_MEMORY
+
+// clang-format off
+
+/*
+ memory synopsis
+
+namespace std
+{
+
+struct allocator_arg_t { };
+inline constexpr allocator_arg_t allocator_arg = allocator_arg_t();
+
+template <class T, class Alloc> struct uses_allocator;
+
+template <class Ptr>
+struct pointer_traits
+{
+ typedef Ptr pointer;
+ typedef <details> element_type;
+ typedef <details> difference_type;
+
+ template <class U> using rebind = <details>;
+
+ static pointer pointer_to(<details>);
+};
+
+template <class T>
+struct pointer_traits<T*>
+{
+ typedef T* pointer;
+ typedef T element_type;
+ typedef ptrdiff_t difference_type;
+
+ template <class U> using rebind = U*;
+
+ static pointer pointer_to(<details>) noexcept; // constexpr in C++20
+};
+
+template <class T> constexpr T* to_address(T* p) noexcept; // C++20
+template <class Ptr> constexpr auto to_address(const Ptr& p) noexcept; // C++20
+
+template <class Alloc>
+struct allocator_traits
+{
+ typedef Alloc allocator_type;
+ typedef typename allocator_type::value_type
+ value_type;
+
+ typedef Alloc::pointer | value_type* pointer;
+ typedef Alloc::const_pointer
+ | pointer_traits<pointer>::rebind<const value_type>
+ const_pointer;
+ typedef Alloc::void_pointer
+ | pointer_traits<pointer>::rebind<void>
+ void_pointer;
+ typedef Alloc::const_void_pointer
+ | pointer_traits<pointer>::rebind<const void>
+ const_void_pointer;
+ typedef Alloc::difference_type
+ | pointer_traits<pointer>::difference_type
+ difference_type;
+ typedef Alloc::size_type
+ | make_unsigned<difference_type>::type
+ size_type;
+ typedef Alloc::propagate_on_container_copy_assignment
+ | false_type propagate_on_container_copy_assignment;
+ typedef Alloc::propagate_on_container_move_assignment
+ | false_type propagate_on_container_move_assignment;
+ typedef Alloc::propagate_on_container_swap
+ | false_type propagate_on_container_swap;
+ typedef Alloc::is_always_equal
+ | is_empty is_always_equal;
+
+ template <class T> using rebind_alloc = Alloc::rebind<T>::other | Alloc<T, Args...>;
+ template <class T> using rebind_traits = allocator_traits<rebind_alloc<T>>;
+
+ static pointer allocate(allocator_type& a, size_type n); // constexpr and [[nodiscard]] in C++20
+ static pointer allocate(allocator_type& a, size_type n, const_void_pointer hint); // constexpr and [[nodiscard]] in C++20
+
+ [[nodiscard]] static constexpr allocation_result<pointer, size_type>
+ allocate_at_least(Alloc& a, size_type n); // Since C++23
+
+ static void deallocate(allocator_type& a, pointer p, size_type n) noexcept; // constexpr in C++20
+
+ template <class T, class... Args>
+ static void construct(allocator_type& a, T* p, Args&&... args); // constexpr in C++20
+
+ template <class T>
+ static void destroy(allocator_type& a, T* p); // constexpr in C++20
+
+ static size_type max_size(const allocator_type& a); // noexcept in C++14, constexpr in C++20
+ static allocator_type select_on_container_copy_construction(const allocator_type& a); // constexpr in C++20
+};
+
+template<class Pointer, class SizeType = size_t>
+struct allocation_result {
+ Pointer ptr;
+ SizeType count;
+}; // Since C++23
+
+template <>
+class allocator<void> // removed in C++20
+{
+public:
+ typedef void* pointer;
+ typedef const void* const_pointer;
+ typedef void value_type;
+
+ template <class _Up> struct rebind {typedef allocator<_Up> other;};
+};
+
+template <class T>
+class allocator
+{
+public:
+ typedef size_t size_type;
+ typedef ptrdiff_t difference_type;
+ typedef T* pointer; // deprecated in C++17, removed in C++20
+ typedef const T* const_pointer; // deprecated in C++17, removed in C++20
+ typedef typename add_lvalue_reference<T>::type
+ reference; // deprecated in C++17, removed in C++20
+ typedef typename add_lvalue_reference<const T>::type
+ const_reference; // deprecated in C++17, removed in C++20
+
+ typedef T value_type;
+
+ template <class U> struct rebind {typedef allocator<U> other;}; // deprecated in C++17, removed in C++20
+
+ typedef true_type propagate_on_container_move_assignment;
+ typedef true_type is_always_equal; // Deprecated in C++23, removed in C++26
+
+ constexpr allocator() noexcept; // constexpr in C++20
+ constexpr allocator(const allocator&) noexcept; // constexpr in C++20
+ template <class U>
+ constexpr allocator(const allocator<U>&) noexcept; // constexpr in C++20
+ ~allocator(); // constexpr in C++20
+ pointer address(reference x) const noexcept; // deprecated in C++17, removed in C++20
+ const_pointer address(const_reference x) const noexcept; // deprecated in C++17, removed in C++20
+ T* allocate(size_t n, const void* hint); // deprecated in C++17, removed in C++20
+ T* allocate(size_t n); // constexpr in C++20
+ void deallocate(T* p, size_t n) noexcept; // constexpr in C++20
+ size_type max_size() const noexcept; // deprecated in C++17, removed in C++20
+ template<class U, class... Args>
+ void construct(U* p, Args&&... args); // deprecated in C++17, removed in C++20
+ template <class U>
+ void destroy(U* p); // deprecated in C++17, removed in C++20
+};
+
+template <class T, class U>
+bool operator==(const allocator<T>&, const allocator<U>&) noexcept; // constexpr in C++20
+
+template <class T, class U>
+bool operator!=(const allocator<T>&, const allocator<U>&) noexcept; // removed in C++20
+
+template <class OutputIterator, class T>
+class raw_storage_iterator // deprecated in C++17, removed in C++20
+ : public iterator<output_iterator_tag, void, void, void, void> // until C++17
+{
+public:
+ typedef output_iterator_tag iterator_category;
+ typedef void value_type;
+ typedef void difference_type; // until C++20
+ typedef ptrdiff_t difference_type; // since C++20
+ typedef void pointer;
+ typedef void reference;
+
+ explicit raw_storage_iterator(OutputIterator x);
+ raw_storage_iterator& operator*();
+ raw_storage_iterator& operator=(const T& element);
+ raw_storage_iterator& operator++();
+ raw_storage_iterator operator++(int);
+};
+
+template <class T> pair<T*,ptrdiff_t> get_temporary_buffer(ptrdiff_t n) noexcept;
+template <class T> void return_temporary_buffer(T* p) noexcept;
+
+template <class T> T* addressof(T& r) noexcept;
+template <class T> T* addressof(const T&& r) noexcept = delete;
+
+template <class InputIterator, class ForwardIterator>
+ForwardIterator
+uninitialized_copy(InputIterator first, InputIterator last, ForwardIterator result);
+
+namespace ranges {
+
+template<class InputIterator, class OutputIterator>
+using uninitialized_copy_result = in_out_result<InputIterator, OutputIterator>; // since C++20
+
+template<input_iterator InputIterator, sentinel-for<InputIterator> Sentinel1, nothrow-forward-iterator OutputIterator, nothrow-sentinel-for<OutputIterator> Sentinel2>
+ requires constructible_from<iter_value_t<OutputIterator>, iter_reference_t<InputIterator>>
+uninitialized_copy_result<InputIterator, OutputIterator>
+uninitialized_copy(InputIterator ifirst, Sentinel1 ilast, OutputIterator ofirst, Sentinel2 olast); // since C++20
+
+template<input_range InputRange, nothrow-forward-range OutputRange>
+ requires constructible_from<range_value_t<OutputRange>, range_reference_t<InputRange>>
+uninitialized_copy_result<borrowed_iterator_t<InputRange>, borrowed_iterator_t<OutputRange>>
+uninitialized_copy(InputRange&& in_range, OutputRange&& out_range); // since C++20
+
+}
+
+template <class InputIterator, class Size, class ForwardIterator>
+ForwardIterator
+uninitialized_copy_n(InputIterator first, Size n, ForwardIterator result);
+
+namespace ranges {
+
+template<class InputIterator, class OutputIterator>
+using uninitialized_copy_n_result = in_out_result<InputIterator, OutputIterator>; // since C++20
+
+template<input_iterator InputIterator, nothrow-forward-iterator OutputIterator, nothrow-sentinel-for<OutputIterator> Sentinel>
+ requires constructible_from<iter_value_t<OutputIterator>, iter_reference_t<InputIterator>>
+uninitialized_copy_n_result<InputIterator, OutputIterator>
+uninitialized_copy_n(InputIterator ifirst, iter_difference_t<InputIterator> n, OutputIterator ofirst, Sentinel olast); // since C++20
+
+}
+
+template <class ForwardIterator, class T>
+void uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x);
+
+namespace ranges {
+
+template <nothrow-forward-iterator ForwardIterator, nothrow-sentinel-for<ForwardIterator> Sentinel, class T>
+ requires constructible_from<iter_value_t<ForwardIterator>, const T&>
+ForwardIterator uninitialized_fill(ForwardIterator first, Sentinel last, const T& x); // since C++20
+
+template <nothrow-forward-range ForwardRange, class T>
+ requires constructible_from<range_value_t<ForwardRange>, const T&>
+borrowed_iterator_t<ForwardRange> uninitialized_fill(ForwardRange&& range, const T& x); // since C++20
+
+}
+
+template <class ForwardIterator, class Size, class T>
+ForwardIterator
+uninitialized_fill_n(ForwardIterator first, Size n, const T& x);
+
+namespace ranges {
+
+template <nothrow-forward-iterator ForwardIterator, class T>
+ requires constructible_from<iter_value_t<ForwardIterator>, const T&>
+ForwardIterator uninitialized_fill_n(ForwardIterator first, iter_difference_t<ForwardIterator> n); // since C++20
+
+}
+
+template <class T, class ...Args>
+constexpr T* construct_at(T* location, Args&& ...args); // since C++20
+
+namespace ranges {
+ template<class T, class... Args>
+ constexpr T* construct_at(T* location, Args&&... args); // since C++20
+}
+
+template <class T>
+void destroy_at(T* location); // constexpr in C++20
+
+namespace ranges {
+ template<destructible T>
+ constexpr void destroy_at(T* location) noexcept; // since C++20
+}
+
+template <class ForwardIterator>
+void destroy(ForwardIterator first, ForwardIterator last); // constexpr in C++20
+
+namespace ranges {
+ template<nothrow-input-iterator InputIterator, nothrow-sentinel-for<InputIterator> Sentinel>
+ requires destructible<iter_value_t<InputIterator>>
+ constexpr InputIterator destroy(InputIterator first, Sentinel last) noexcept; // since C++20
+ template<nothrow-input-range InputRange>
+ requires destructible<range_value_t<InputRange>>
+ constexpr borrowed_iterator_t<InputRange> destroy(InputRange&& range) noexcept; // since C++20
+}
+
+template <class ForwardIterator, class Size>
+ForwardIterator destroy_n(ForwardIterator first, Size n); // constexpr in C++20
+
+namespace ranges {
+ template<nothrow-input-iterator InputIterator>
+ requires destructible<iter_value_t<InputIterator>>
+ constexpr InputIterator destroy_n(InputIterator first, iter_difference_t<InputIterator> n) noexcept; // since C++20
+}
+
+template <class InputIterator, class ForwardIterator>
+ ForwardIterator uninitialized_move(InputIterator first, InputIterator last, ForwardIterator result);
+
+namespace ranges {
+
+template<class InputIterator, class OutputIterator>
+using uninitialized_move_result = in_out_result<InputIterator, OutputIterator>; // since C++20
+
+template <input_iterator InputIterator, sentinel_for<InputIterator> Sentinel1, nothrow-forward-iterator OutputIterator, nothrow-sentinel-for<O> Sentinel2>
+ requires constructible_from<iter_value_t<OutputIterator>, iter_rvalue_reference_t<InputIterator>>
+uninitialized_move_result<InputIterator, OutputIterator>
+uninitialized_move(InputIterator ifirst, Sentinel1 ilast, OutputIterator ofirst, Sentinel2 olast); // since C++20
+
+template<input_range InputRange, nothrow-forward-range OutputRange>
+ requires constructible_from<range_value_t<OutputRange>, range_rvalue_reference_t<InputRange>>
+uninitialized_move_result<borrowed_iterator_t<InputRange>, borrowed_iterator_t<OutputRange>>
+uninitialized_move(InputRange&& in_range, OutputRange&& out_range); // since C++20
+
+}
+
+template <class InputIterator, class Size, class ForwardIterator>
+ pair<InputIterator,ForwardIterator> uninitialized_move_n(InputIterator first, Size n, ForwardIterator result);
+
+namespace ranges {
+
+template<class InputIterator, class OutputIterator>
+using uninitialized_move_n_result = in_out_result<InputIterator, OutputIterator>; // since C++20
+
+template<input_iterator InputIterator, nothrow-forward-iterator OutputIterator, nothrow-sentinel-for<OutputIterator> Sentinel>
+ requires constructible_from<iter_value_t<OutputIterator>, iter_rvalue_reference_t<InputIterator>>
+uninitialized_move_n_result<InputIterator, OutputIterator>
+uninitialized_move_n(InputIterator ifirst, iter_difference_t<InputIterator> n, OutputIterator ofirst, Sentinel olast); // since C++20
+
+}
+
+template <class ForwardIterator>
+ void uninitialized_value_construct(ForwardIterator first, ForwardIterator last);
+
+namespace ranges {
+
+template <nothrow-forward-iterator ForwardIterator, nothrow-sentinel-for<ForwardIterator> Sentinel>
+ requires default_initializable<iter_value_t<ForwardIterator>>
+ ForwardIterator uninitialized_value_construct(ForwardIterator first, Sentinel last); // since C++20
+
+template <nothrow-forward-range ForwardRange>
+ requires default_initializable<range_value_t<ForwardRange>>
+ borrowed_iterator_t<ForwardRange> uninitialized_value_construct(ForwardRange&& r); // since C++20
+
+}
+
+template <class ForwardIterator, class Size>
+ ForwardIterator uninitialized_value_construct_n(ForwardIterator first, Size n);
+
+namespace ranges {
+
+template <nothrow-forward-iterator ForwardIterator>
+ requires default_initializable<iter_value_t<ForwardIterator>>
+ ForwardIterator uninitialized_value_construct_n(ForwardIterator first, iter_difference_t<ForwardIterator> n); // since C++20
+
+}
+
+template <class ForwardIterator>
+ void uninitialized_default_construct(ForwardIterator first, ForwardIterator last);
+
+namespace ranges {
+
+template <nothrow-forward-iterator ForwardIterator, nothrow-sentinel-for<ForwardIterator> Sentinel>
+ requires default_initializable<iter_value_t<ForwardIterator>>
+ ForwardIterator uninitialized_default_construct(ForwardIterator first, Sentinel last); // since C++20
+
+template <nothrow-forward-range ForwardRange>
+ requires default_initializable<range_value_t<ForwardRange>>
+ borrowed_iterator_t<ForwardRange> uninitialized_default_construct(ForwardRange&& r); // since C++20
+
+}
+
+template <class ForwardIterator, class Size>
+ ForwardIterator uninitialized_default_construct_n(ForwardIterator first, Size n);
+
+namespace ranges {
+
+template <nothrow-forward-iterator ForwardIterator>
+ requires default_initializable<iter_value_t<ForwardIterator>>
+ ForwardIterator uninitialized_default_construct_n(ForwardIterator first, iter_difference_t<ForwardIterator> n); // since C++20
+
+}
+
+template <class Y> struct auto_ptr_ref {}; // deprecated in C++11, removed in C++17
+
+template<class X>
+class auto_ptr // deprecated in C++11, removed in C++17
+{
+public:
+ typedef X element_type;
+
+ explicit auto_ptr(X* p =0) throw();
+ auto_ptr(auto_ptr&) throw();
+ template<class Y> auto_ptr(auto_ptr<Y>&) throw();
+ auto_ptr& operator=(auto_ptr&) throw();
+ template<class Y> auto_ptr& operator=(auto_ptr<Y>&) throw();
+ auto_ptr& operator=(auto_ptr_ref<X> r) throw();
+ ~auto_ptr() throw();
+
+ typename add_lvalue_reference<X>::type operator*() const throw();
+ X* operator->() const throw();
+ X* get() const throw();
+ X* release() throw();
+ void reset(X* p =0) throw();
+
+ auto_ptr(auto_ptr_ref<X>) throw();
+ template<class Y> operator auto_ptr_ref<Y>() throw();
+ template<class Y> operator auto_ptr<Y>() throw();
+};
+
+template <class T>
+struct default_delete
+{
+ constexpr default_delete() noexcept = default;
+ template <class U> constexpr default_delete(const default_delete<U>&) noexcept; // constexpr since C++23
+
+ constexpr void operator()(T*) const noexcept; // constexpr since C++23
+};
+
+template <class T>
+struct default_delete<T[]>
+{
+ constexpr default_delete() noexcept = default;
+ template <class U> constexpr default_delete(const default_delete <U[]>&) noexcept; // constexpr since C++23
+ constexpr void operator()(T*) const noexcept; // constexpr since C++23
+ template <class U> void operator()(U*) const = delete;
+};
+
+template <class T, class D = default_delete<T>>
+class unique_ptr
+{
+public:
+ typedef see below pointer;
+ typedef T element_type;
+ typedef D deleter_type;
+
+ // constructors
+ constexpr unique_ptr() noexcept;
+ constexpr explicit unique_ptr(pointer p) noexcept; // constexpr since C++23
+ constexpr unique_ptr(pointer p, see below d1) noexcept; // constexpr since C++23
+ constexpr unique_ptr(pointer p, see below d2) noexcept; // constexpr since C++23
+ constexpr unique_ptr(unique_ptr&& u) noexcept; // constexpr since C++23
+ constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }
+ template <class U, class E>
+ constexpr unique_ptr(unique_ptr<U, E>&& u) noexcept; // constexpr since C++23
+ template <class U>
+ unique_ptr(auto_ptr<U>&& u) noexcept; // removed in C++17
+
+ // destructor
+ constexpr ~unique_ptr(); // constexpr since C++23
+
+ // assignment
+ constexpr unique_ptr& operator=(unique_ptr&& u) noexcept; // constexpr since C++23
+ template <class U, class E>
+ constexpr unique_ptr& operator=(unique_ptr<U, E>&& u) noexcept; // constexpr since C++23
+ constexpr unique_ptr& operator=(nullptr_t) noexcept; // constexpr since C++23
+
+ // observers
+ constexpr
+ add_lvalue_reference<T>::type operator*() const noexcept(see below); // constexpr since C++23
+ constexpr pointer operator->() const noexcept; // constexpr since C++23
+ constexpr pointer get() const noexcept; // constexpr since C++23
+ constexpr deleter_type& get_deleter() noexcept; // constexpr since C++23
+ constexpr const deleter_type& get_deleter() const noexcept; // constexpr since C++23
+ constexpr explicit operator bool() const noexcept; // constexpr since C++23
+
+ // modifiers
+ constexpr pointer release() noexcept; // constexpr since C++23
+ constexpr void reset(pointer p = pointer()) noexcept; // constexpr since C++23
+ constexpr void swap(unique_ptr& u) noexcept; // constexpr since C++23
+};
+
+template <class T, class D>
+class unique_ptr<T[], D>
+{
+public:
+ typedef implementation-defined pointer;
+ typedef T element_type;
+ typedef D deleter_type;
+
+ // constructors
+ constexpr unique_ptr() noexcept;
+ constexpr explicit unique_ptr(pointer p) noexcept; // constexpr since C++23
+ constexpr unique_ptr(pointer p, see below d) noexcept; // constexpr since C++23
+ constexpr unique_ptr(pointer p, see below d) noexcept; // constexpr since C++23
+ constexpr unique_ptr(unique_ptr&& u) noexcept; // constexpr since C++23
+ template <class U, class E>
+ constexpr unique_ptr(unique_ptr <U, E>&& u) noexcept; // constexpr since C++23
+ constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }
+
+ // destructor
+ constexpr ~unique_ptr(); // constexpr since C++23
+
+ // assignment
+ constexpr unique_ptr& operator=(unique_ptr&& u) noexcept; // constexpr since C++23
+ template <class U, class E>
+ constexpr unique_ptr& operator=(unique_ptr <U, E>&& u) noexcept; // constexpr since C++23
+ constexpr unique_ptr& operator=(nullptr_t) noexcept; // constexpr since C++23
+
+ // observers
+ constexpr T& operator[](size_t i) const; // constexpr since C++23
+ constexpr pointer get() const noexcept; // constexpr since C++23
+ constexpr deleter_type& get_deleter() noexcept; // constexpr since C++23
+ constexpr const deleter_type& get_deleter() const noexcept; // constexpr since C++23
+ constexpr explicit operator bool() const noexcept; // constexpr since C++23
+
+ // modifiers
+ constexpr pointer release() noexcept; // constexpr since C++23
+ constexpr void reset(pointer p = pointer()) noexcept; // constexpr since C++23
+ constexpr void reset(nullptr_t) noexcept; // constexpr since C++23
+ template <class U> void reset(U) = delete;
+ constexpr void swap(unique_ptr& u) noexcept; // constexpr since C++23
+};
+
+template <class T, class D>
+ constexpr void swap(unique_ptr<T, D>& x, unique_ptr<T, D>& y) noexcept; // constexpr since C++23
+
+template <class T1, class D1, class T2, class D2>
+ constexpr bool operator==(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y); // constexpr since C++23
+template <class T1, class D1, class T2, class D2>
+ bool operator!=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y); // removed in C++20
+template <class T1, class D1, class T2, class D2>
+ bool operator<(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
+template <class T1, class D1, class T2, class D2>
+ bool operator<=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
+template <class T1, class D1, class T2, class D2>
+ bool operator>(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
+template <class T1, class D1, class T2, class D2>
+ bool operator>=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
+template<class T1, class D1, class T2, class D2>
+ requires three_way_comparable_with<typename unique_ptr<T1, D1>::pointer,
+ typename unique_ptr<T2, D2>::pointer>
+ compare_three_way_result_t<typename unique_ptr<T1, D1>::pointer,
+ typename unique_ptr<T2, D2>::pointer>
+ operator<=>(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y); // C++20
+
+template <class T, class D>
+ constexpr bool operator==(const unique_ptr<T, D>& x, nullptr_t) noexcept; // constexpr since C++23
+template <class T, class D>
+ bool operator==(nullptr_t, const unique_ptr<T, D>& y) noexcept; // removed in C++20
+template <class T, class D>
+ bool operator!=(const unique_ptr<T, D>& x, nullptr_t) noexcept; // removed in C++20
+template <class T, class D>
+ bool operator!=(nullptr_t, const unique_ptr<T, D>& y) noexcept; // removed in C++20
+
+template <class T, class D>
+ constexpr bool operator<(const unique_ptr<T, D>& x, nullptr_t); // constexpr since C++23
+template <class T, class D>
+ constexpr bool operator<(nullptr_t, const unique_ptr<T, D>& y); // constexpr since C++23
+template <class T, class D>
+ constexpr bool operator<=(const unique_ptr<T, D>& x, nullptr_t); // constexpr since C++23
+template <class T, class D>
+ constexpr bool operator<=(nullptr_t, const unique_ptr<T, D>& y); // constexpr since C++23
+template <class T, class D>
+ constexpr bool operator>(const unique_ptr<T, D>& x, nullptr_t); // constexpr since C++23
+template <class T, class D>
+ constexpr bool operator>(nullptr_t, const unique_ptr<T, D>& y); // constexpr since C++23
+template <class T, class D>
+ constexpr bool operator>=(const unique_ptr<T, D>& x, nullptr_t); // constexpr since C++23
+template <class T, class D>
+ constexpr bool operator>=(nullptr_t, const unique_ptr<T, D>& y); // constexpr since C++23
+template<class T, class D>
+ requires three_way_comparable<typename unique_ptr<T, D>::pointer>
+ compare_three_way_result_t<typename unique_ptr<T, D>::pointer>
+ constexpr operator<=>(const unique_ptr<T, D>& x, nullptr_t); // C++20, constexpr since C++23
+
+class bad_weak_ptr
+ : public std::exception
+{
+ bad_weak_ptr() noexcept;
+};
+
+template<class T, class... Args>
+constexpr unique_ptr<T> make_unique(Args&&... args); // C++14, constexpr since C++23
+template<class T>
+constexpr unique_ptr<T> make_unique(size_t n); // C++14, constexpr since C++23
+template<class T, class... Args> unspecified make_unique(Args&&...) = delete; // C++14, T == U[N]
+
+template<class T>
+ constexpr unique_ptr<T> make_unique_for_overwrite(); // T is not array, C++20, constexpr since C++23
+template<class T>
+ constexpr unique_ptr<T> make_unique_for_overwrite(size_t n); // T is U[], C++20, constexpr since C++23
+template<class T, class... Args>
+ unspecified make_unique_for_overwrite(Args&&...) = delete; // T is U[N], C++20
+
+template<class E, class T, class Y, class D>
+ basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, unique_ptr<Y, D> const& p);
+
+template<class T>
+class shared_ptr
+{
+public:
+ typedef T element_type; // until C++17
+ typedef remove_extent_t<T> element_type; // since C++17
+ typedef weak_ptr<T> weak_type; // C++17
+
+ // constructors:
+ constexpr shared_ptr() noexcept;
+ template<class Y> explicit shared_ptr(Y* p);
+ template<class Y, class D> shared_ptr(Y* p, D d);
+ template<class Y, class D, class A> shared_ptr(Y* p, D d, A a);
+ template <class D> shared_ptr(nullptr_t p, D d);
+ template <class D, class A> shared_ptr(nullptr_t p, D d, A a);
+ template<class Y> shared_ptr(const shared_ptr<Y>& r, T *p) noexcept;
+ shared_ptr(const shared_ptr& r) noexcept;
+ template<class Y> shared_ptr(const shared_ptr<Y>& r) noexcept;
+ shared_ptr(shared_ptr&& r) noexcept;
+ template<class Y> shared_ptr(shared_ptr<Y>&& r) noexcept;
+ template<class Y> explicit shared_ptr(const weak_ptr<Y>& r);
+ template<class Y> shared_ptr(auto_ptr<Y>&& r); // removed in C++17
+ template <class Y, class D> shared_ptr(unique_ptr<Y, D>&& r);
+ shared_ptr(nullptr_t) : shared_ptr() { }
+
+ // destructor:
+ ~shared_ptr();
+
+ // assignment:
+ shared_ptr& operator=(const shared_ptr& r) noexcept;
+ template<class Y> shared_ptr& operator=(const shared_ptr<Y>& r) noexcept;
+ shared_ptr& operator=(shared_ptr&& r) noexcept;
+ template<class Y> shared_ptr& operator=(shared_ptr<Y>&& r);
+ template<class Y> shared_ptr& operator=(auto_ptr<Y>&& r); // removed in C++17
+ template <class Y, class D> shared_ptr& operator=(unique_ptr<Y, D>&& r);
+
+ // modifiers:
+ void swap(shared_ptr& r) noexcept;
+ void reset() noexcept;
+ template<class Y> void reset(Y* p);
+ template<class Y, class D> void reset(Y* p, D d);
+ template<class Y, class D, class A> void reset(Y* p, D d, A a);
+
+ // observers:
+ T* get() const noexcept;
+ T& operator*() const noexcept;
+ T* operator->() const noexcept;
+ long use_count() const noexcept;
+ bool unique() const noexcept; // deprected in C++17, removed in C++20
+ explicit operator bool() const noexcept;
+ template<class U> bool owner_before(shared_ptr<U> const& b) const noexcept;
+ template<class U> bool owner_before(weak_ptr<U> const& b) const noexcept;
+};
+
+template<class T>
+shared_ptr(weak_ptr<T>) -> shared_ptr<T>;
+template<class T, class D>
+shared_ptr(unique_ptr<T, D>) -> shared_ptr<T>;
+
+// shared_ptr comparisons:
+template<class T, class U>
+ bool operator==(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
+template<class T, class U>
+ bool operator!=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept; // removed in C++20
+template<class T, class U>
+ bool operator<(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept; // removed in C++20
+template<class T, class U>
+ bool operator>(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept; // removed in C++20
+template<class T, class U>
+ bool operator<=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept; // removed in C++20
+template<class T, class U>
+ bool operator>=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept; // removed in C++20
+template<class T, class U>
+ strong_ordering operator<=>(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept; // C++20
+
+template <class T>
+ bool operator==(const shared_ptr<T>& x, nullptr_t) noexcept;
+template <class T>
+ bool operator==(nullptr_t, const shared_ptr<T>& y) noexcept; // removed in C++20
+template <class T>
+ bool operator!=(const shared_ptr<T>& x, nullptr_t) noexcept; // removed in C++20
+template <class T>
+ bool operator!=(nullptr_t, const shared_ptr<T>& y) noexcept; // removed in C++20
+template <class T>
+ bool operator<(const shared_ptr<T>& x, nullptr_t) noexcept; // removed in C++20
+template <class T>
+ bool operator<(nullptr_t, const shared_ptr<T>& y) noexcept; // removed in C++20
+template <class T>
+ bool operator<=(const shared_ptr<T>& x, nullptr_t) noexcept; // removed in C++20
+template <class T>
+ bool operator<=(nullptr_t, const shared_ptr<T>& y) noexcept; // removed in C++20
+template <class T>
+ bool operator>(const shared_ptr<T>& x, nullptr_t) noexcept; // removed in C++20
+template <class T>
+ bool operator>(nullptr_t, const shared_ptr<T>& y) noexcept; // removed in C++20
+template <class T>
+ bool operator>=(const shared_ptr<T>& x, nullptr_t) noexcept; // removed in C++20
+template <class T>
+ bool operator>=(nullptr_t, const shared_ptr<T>& y) noexcept; // removed in C++20
+template<class T>
+ strong_ordering operator<=>(shared_ptr<T> const& x, nullptr_t) noexcept; // C++20
+
+// shared_ptr specialized algorithms:
+template<class T> void swap(shared_ptr<T>& a, shared_ptr<T>& b) noexcept;
+
+// shared_ptr casts:
+template<class T, class U>
+ shared_ptr<T> static_pointer_cast(shared_ptr<U> const& r) noexcept;
+template<class T, class U>
+ shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const& r) noexcept;
+template<class T, class U>
+ shared_ptr<T> const_pointer_cast(shared_ptr<U> const& r) noexcept;
+
+// shared_ptr I/O:
+template<class E, class T, class Y>
+ basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, shared_ptr<Y> const& p);
+
+// shared_ptr get_deleter:
+template<class D, class T> D* get_deleter(shared_ptr<T> const& p) noexcept;
+
+template<class T, class... Args>
+ shared_ptr<T> make_shared(Args&&... args); // T is not an array
+template<class T, class A, class... Args>
+ shared_ptr<T> allocate_shared(const A& a, Args&&... args); // T is not an array
+
+template<class T>
+ shared_ptr<T> make_shared(size_t N); // T is U[] (since C++20)
+template<class T, class A>
+ shared_ptr<T> allocate_shared(const A& a, size_t N); // T is U[] (since C++20)
+
+template<class T>
+ shared_ptr<T> make_shared(); // T is U[N] (since C++20)
+template<class T, class A>
+ shared_ptr<T> allocate_shared(const A& a); // T is U[N] (since C++20)
+
+template<class T>
+ shared_ptr<T> make_shared(size_t N, const remove_extent_t<T>& u); // T is U[] (since C++20)
+template<class T, class A>
+ shared_ptr<T> allocate_shared(const A& a, size_t N, const remove_extent_t<T>& u); // T is U[] (since C++20)
+
+template<class T> shared_ptr<T>
+ make_shared(const remove_extent_t<T>& u); // T is U[N] (since C++20)
+template<class T, class A>
+ shared_ptr<T> allocate_shared(const A& a, const remove_extent_t<T>& u); // T is U[N] (since C++20)
+
+template<class T>
+ shared_ptr<T> make_shared_for_overwrite(); // T is not U[], C++20
+template<class T, class A>
+ shared_ptr<T> allocate_shared_for_overwrite(const A& a); // T is not U[], C++20
+
+template<class T>
+ shared_ptr<T> make_shared_for_overwrite(size_t N); // T is U[], C++20
+template<class T, class A>
+ shared_ptr<T> allocate_shared_for_overwrite(const A& a, size_t N); // T is U[], C++20
+
+template<class T>
+class weak_ptr
+{
+public:
+ typedef T element_type; // until C++17
+ typedef remove_extent_t<T> element_type; // since C++17
+
+ // constructors
+ constexpr weak_ptr() noexcept;
+ template<class Y> weak_ptr(shared_ptr<Y> const& r) noexcept;
+ weak_ptr(weak_ptr const& r) noexcept;
+ template<class Y> weak_ptr(weak_ptr<Y> const& r) noexcept;
+ weak_ptr(weak_ptr&& r) noexcept; // C++14
+ template<class Y> weak_ptr(weak_ptr<Y>&& r) noexcept; // C++14
+
+ // destructor
+ ~weak_ptr();
+
+ // assignment
+ weak_ptr& operator=(weak_ptr const& r) noexcept;
+ template<class Y> weak_ptr& operator=(weak_ptr<Y> const& r) noexcept;
+ template<class Y> weak_ptr& operator=(shared_ptr<Y> const& r) noexcept;
+ weak_ptr& operator=(weak_ptr&& r) noexcept; // C++14
+ template<class Y> weak_ptr& operator=(weak_ptr<Y>&& r) noexcept; // C++14
+
+ // modifiers
+ void swap(weak_ptr& r) noexcept;
+ void reset() noexcept;
+
+ // observers
+ long use_count() const noexcept;
+ bool expired() const noexcept;
+ shared_ptr<T> lock() const noexcept;
+ template<class U> bool owner_before(shared_ptr<U> const& b) const noexcept;
+ template<class U> bool owner_before(weak_ptr<U> const& b) const noexcept;
+};
+
+template<class T>
+weak_ptr(shared_ptr<T>) -> weak_ptr<T>;
+
+// weak_ptr specialized algorithms:
+template<class T> void swap(weak_ptr<T>& a, weak_ptr<T>& b) noexcept;
+
+// class owner_less:
+template<class T> struct owner_less;
+
+template<class T>
+struct owner_less<shared_ptr<T> >
+ : binary_function<shared_ptr<T>, shared_ptr<T>, bool>
+{
+ typedef bool result_type;
+ bool operator()(shared_ptr<T> const&, shared_ptr<T> const&) const noexcept;
+ bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const noexcept;
+ bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const noexcept;
+};
+
+template<class T>
+struct owner_less<weak_ptr<T> >
+ : binary_function<weak_ptr<T>, weak_ptr<T>, bool>
+{
+ typedef bool result_type;
+ bool operator()(weak_ptr<T> const&, weak_ptr<T> const&) const noexcept;
+ bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const noexcept;
+ bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const noexcept;
+};
+
+template <> // Added in C++14
+struct owner_less<void>
+{
+ template <class _Tp, class _Up>
+ bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const noexcept;
+ template <class _Tp, class _Up>
+ bool operator()( shared_ptr<_Tp> const& __x, weak_ptr<_Up> const& __y) const noexcept;
+ template <class _Tp, class _Up>
+ bool operator()( weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const noexcept;
+ template <class _Tp, class _Up>
+ bool operator()( weak_ptr<_Tp> const& __x, weak_ptr<_Up> const& __y) const noexcept;
+
+ typedef void is_transparent;
+};
+
+template<class T>
+class enable_shared_from_this
+{
+protected:
+ constexpr enable_shared_from_this() noexcept;
+ enable_shared_from_this(enable_shared_from_this const&) noexcept;
+ enable_shared_from_this& operator=(enable_shared_from_this const&) noexcept;
+ ~enable_shared_from_this();
+public:
+ shared_ptr<T> shared_from_this();
+ shared_ptr<T const> shared_from_this() const;
+};
+
+template<class T>
+ bool atomic_is_lock_free(const shared_ptr<T>* p);
+template<class T>
+ shared_ptr<T> atomic_load(const shared_ptr<T>* p);
+template<class T>
+ shared_ptr<T> atomic_load_explicit(const shared_ptr<T>* p, memory_order mo);
+template<class T>
+ void atomic_store(shared_ptr<T>* p, shared_ptr<T> r);
+template<class T>
+ void atomic_store_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
+template<class T>
+ shared_ptr<T> atomic_exchange(shared_ptr<T>* p, shared_ptr<T> r);
+template<class T>
+ shared_ptr<T>
+ atomic_exchange_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
+template<class T>
+ bool
+ atomic_compare_exchange_weak(shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
+template<class T>
+ bool
+ atomic_compare_exchange_strong( shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
+template<class T>
+ bool
+ atomic_compare_exchange_weak_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
+ shared_ptr<T> w, memory_order success,
+ memory_order failure);
+template<class T>
+ bool
+ atomic_compare_exchange_strong_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
+ shared_ptr<T> w, memory_order success,
+ memory_order failure);
+// Hash support
+template <class T> struct hash;
+template <class T, class D> struct hash<unique_ptr<T, D> >;
+template <class T> struct hash<shared_ptr<T> >;
+
+template <class T, class Alloc>
+ inline constexpr bool uses_allocator_v = uses_allocator<T, Alloc>::value;
+
+// [allocator.uses.construction], uses-allocator construction
+template<class T, class Alloc, class... Args>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++20
+ Args&&... args) noexcept;
+template<class T, class Alloc, class Tuple1, class Tuple2>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++20
+ piecewise_construct_t,
+ Tuple1&& x, Tuple2&& y) noexcept;
+template<class T, class Alloc>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc) noexcept; // since C++20
+template<class T, class Alloc, class U, class V>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++20
+ U&& u, V&& v) noexcept;
+template<class T, class Alloc, class U, class V>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++23
+ pair<U, V>& pr) noexcept;
+template<class T, class Alloc, class U, class V>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++20
+ const pair<U, V>& pr) noexcept;
+template<class T, class Alloc, class U, class V>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++20
+ pair<U, V>&& pr) noexcept;
+template<class T, class Alloc, class U, class V>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++23
+ const pair<U, V>&& pr) noexcept;
+template<class T, class Alloc, pair-like P>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++20
+ P&& p) noexcept;
+template<class T, class Alloc, class U>
+ constexpr auto uses_allocator_construction_args(const Alloc& alloc, // since C++20
+ U&& u) noexcept;
+template<class T, class Alloc, class... Args>
+ constexpr T make_obj_using_allocator(const Alloc& alloc, Args&&... args); // since C++20
+template<class T, class Alloc, class... Args>
+ constexpr T* uninitialized_construct_using_allocator(T* p, // since C++20
+ const Alloc& alloc, Args&&... args);
+
+// [ptr.align]
+void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
+
+template<size_t N, class T>
+[[nodiscard]] constexpr T* assume_aligned(T* ptr); // since C++20
+
+// [out.ptr.t], class template out_ptr_t
+template<class Smart, class Pointer, class... Args>
+ class out_ptr_t; // since c++23
+
+// [out.ptr], function template out_ptr
+template<class Pointer = void, class Smart, class... Args>
+ auto out_ptr(Smart& s, Args&&... args); // since c++23
+
+// [inout.ptr.t], class template inout_ptr_t
+template<class Smart, class Pointer, class... Args>
+ class inout_ptr_t; // since c++23
+
+// [inout.ptr], function template inout_ptr
+template<class Pointer = void, class Smart, class... Args>
+ auto inout_ptr(Smart& s, Args&&... args); // since c++23
+
+} // std
+
+*/
+
+// clang-format on
+
+#include <__config>
+#include <__memory/addressof.h>
+#include <__memory/align.h>
+#include <__memory/allocator.h>
+#include <__memory/allocator_arg_t.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/auto_ptr.h>
+#include <__memory/inout_ptr.h>
+#include <__memory/out_ptr.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/raw_storage_iterator.h>
+#include <__memory/shared_ptr.h>
+#include <__memory/temporary_buffer.h>
+#include <__memory/uninitialized_algorithms.h>
+#include <__memory/unique_ptr.h>
+#include <__memory/uses_allocator.h>
+
+// standard-mandated includes
+
+#if _LIBCPP_STD_VER >= 17
+# include <__memory/construct_at.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+# include <__memory/assume_aligned.h>
+# include <__memory/concepts.h>
+# include <__memory/ranges_construct_at.h>
+# include <__memory/ranges_uninitialized_algorithms.h>
+# include <__memory/uses_allocator_construction.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+# include <__memory/allocate_at_least.h>
+#endif
+
+#include <version>
+
+// [memory.syn]
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstddef>
+# include <cstdint>
+# include <cstdlib>
+# include <cstring>
+# include <iosfwd>
+# include <iterator>
+# include <new>
+# include <stdexcept>
+# include <tuple>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_MEMORY
diff --git a/libcxx/include/__cxx03/memory_resource b/libcxx/include/__cxx03/memory_resource
new file mode 100644
index 00000000000000..67411054820a1a
--- /dev/null
+++ b/libcxx/include/__cxx03/memory_resource
@@ -0,0 +1,83 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_MEMORY_RESOURCE
+#define _LIBCPP_MEMORY_RESOURCE
+
+/**
+ memory_resource synopsis
+
+// C++17
+
+namespace std::pmr {
+
+ class memory_resource;
+
+ bool operator==(const memory_resource& a,
+ const memory_resource& b) noexcept;
+ bool operator!=(const memory_resource& a,
+ const memory_resource& b) noexcept; // removed in C++20
+
+ template <class Tp> class polymorphic_allocator;
+
+ template <class T1, class T2>
+ bool operator==(const polymorphic_allocator<T1>& a,
+ const polymorphic_allocator<T2>& b) noexcept;
+ template <class T1, class T2>
+ bool operator!=(const polymorphic_allocator<T1>& a,
+ const polymorphic_allocator<T2>& b) noexcept; // removed in C++20
+
+ // Global memory resources
+ memory_resource* set_default_resource(memory_resource* r) noexcept;
+ memory_resource* get_default_resource() noexcept;
+ memory_resource* new_delete_resource() noexcept;
+ memory_resource* null_memory_resource() noexcept;
+
+ // Pool resource classes
+ struct pool_options;
+ class synchronized_pool_resource;
+ class unsynchronized_pool_resource;
+ class monotonic_buffer_resource;
+
+} // namespace std::pmr
+
+ */
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 17
+# include <__memory_resource/memory_resource.h>
+# include <__memory_resource/monotonic_buffer_resource.h>
+# include <__memory_resource/polymorphic_allocator.h>
+# include <__memory_resource/pool_options.h>
+# include <__memory_resource/synchronized_pool_resource.h>
+# include <__memory_resource/unsynchronized_pool_resource.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 14
+# include <cstddef>
+# include <cstdint>
+# include <limits>
+# include <mutex>
+# include <new>
+# include <stdexcept>
+# include <tuple>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <stdexcept>
+#endif
+
+#endif /* _LIBCPP_MEMORY_RESOURCE */
diff --git a/libcxx/include/__cxx03/module.modulemap b/libcxx/include/__cxx03/module.modulemap
new file mode 100644
index 00000000000000..13d0dce34d97e3
--- /dev/null
+++ b/libcxx/include/__cxx03/module.modulemap
@@ -0,0 +1,2136 @@
+// Main C++ standard library interfaces
+module std_algorithm [system] {
+ header "algorithm"
+ export *
+}
+module std_any [system] {
+ header "any"
+ export *
+}
+module std_array [system] {
+ header "array"
+ export *
+}
+module std_atomic [system] {
+ header "atomic"
+ export *
+}
+module std_barrier [system] {
+ header "barrier"
+ export *
+}
+module std_bit [system] {
+ header "bit"
+ export *
+}
+module std_bitset [system] {
+ header "bitset"
+ export *
+}
+module std_charconv [system] {
+ header "charconv"
+ export *
+}
+module std_chrono [system] {
+ header "chrono"
+ export *
+}
+module std_codecvt [system] {
+ header "codecvt"
+ export *
+}
+module std_compare [system] {
+ header "compare"
+ export *
+}
+module std_complex [system] {
+ header "complex"
+ export *
+}
+module std_concepts [system] {
+ header "concepts"
+ export *
+}
+module std_condition_variable [system] {
+ header "condition_variable"
+ export *
+}
+module std_coroutine [system] {
+ header "coroutine"
+ export *
+}
+module std_deque [system] {
+ header "deque"
+ export *
+}
+module std_exception [system] {
+ header "exception"
+ export *
+}
+module std_execution [system] {
+ header "execution"
+ export *
+}
+module std_expected [system] {
+ header "expected"
+ export *
+}
+module std_filesystem [system] {
+ header "filesystem"
+ export *
+}
+module std_format [system] {
+ header "format"
+ export *
+}
+module std_forward_list [system] {
+ header "forward_list"
+ export *
+}
+module std_fstream [system] {
+ header "fstream"
+ export *
+}
+module std_functional [system] {
+ header "functional"
+ export *
+}
+module std_future [system] {
+ header "future"
+ export *
+}
+module std_initializer_list [system] {
+ header "initializer_list"
+ export *
+}
+module std_iomanip [system] {
+ header "iomanip"
+ export *
+}
+module std_ios [system] {
+ header "ios"
+ export *
+}
+module std_iosfwd [system] {
+ header "iosfwd"
+ export *
+}
+module std_iostream [system] {
+ header "iostream"
+ export *
+}
+module std_istream [system] {
+ header "istream"
+ export *
+}
+module std_iterator [system] {
+ header "iterator"
+ export *
+}
+module std_latch [system] {
+ header "latch"
+ export *
+}
+module std_limits [system] {
+ header "limits"
+ export *
+}
+module std_list [system] {
+ header "list"
+ export *
+}
+module std_locale [system] {
+ header "locale"
+ export *
+}
+module std_map [system] {
+ header "map"
+ export *
+}
+module std_mdspan [system] {
+ header "mdspan"
+ export *
+}
+module std_memory [system] {
+ header "memory"
+ export *
+}
+module std_memory_resource [system] {
+ header "memory_resource"
+ export *
+}
+module std_mutex [system] {
+ header "mutex"
+ export *
+}
+module std_new [system] {
+ header "new"
+ export *
+}
+module std_numbers [system] {
+ header "numbers"
+ export *
+}
+module std_numeric [system] {
+ header "numeric"
+ export *
+}
+module std_optional [system] {
+ header "optional"
+ export *
+}
+module std_ostream [system] {
+ header "ostream"
+ export *
+}
+module std_print [system] {
+ header "print"
+ export *
+}
+module std_queue [system] {
+ header "queue"
+ export *
+}
+module std_random [system] {
+ header "random"
+ export *
+}
+module std_ranges [system] {
+ header "ranges"
+ export *
+}
+module std_ratio [system] {
+ header "ratio"
+ export *
+}
+module std_regex [system] {
+ header "regex"
+ export *
+}
+module std_scoped_allocator [system] {
+ header "scoped_allocator"
+ export *
+}
+module std_semaphore [system] {
+ header "semaphore"
+ export *
+}
+module std_set [system] {
+ header "set"
+ export *
+}
+module std_shared_mutex [system] {
+ header "shared_mutex"
+ export std_version
+}
+module std_source_location [system] {
+ header "source_location"
+ export *
+}
+module std_span [system] {
+ header "span"
+ export std_private_ranges_enable_borrowed_range
+ export std_version
+ export std_private_span_span_fwd
+}
+module std_sstream [system] {
+ header "sstream"
+ export *
+}
+module std_stack [system] {
+ header "stack"
+ export *
+}
+module std_stdexcept [system] {
+ header "stdexcept"
+ export *
+}
+module std_stop_token {
+ header "stop_token"
+ export *
+}
+module std_streambuf [system] {
+ header "streambuf"
+ export *
+}
+module std_string [system] {
+ header "string"
+ export *
+}
+module std_string_view [system] {
+ header "string_view"
+ export *
+}
+module std_strstream [system] {
+ header "strstream"
+ export *
+}
+module std_syncstream [system] {
+ header "syncstream"
+ export *
+}
+module std_system_error [system] {
+ header "system_error"
+ export *
+}
+module std_thread [system] {
+ header "thread"
+ export *
+}
+module std_tuple [system] {
+ header "tuple"
+ export *
+}
+module std_type_traits [system] {
+ header "type_traits"
+ export *
+}
+module std_typeindex [system] {
+ header "typeindex"
+ export *
+}
+module std_typeinfo [system] {
+ header "typeinfo"
+ export *
+}
+module std_unordered_map [system] {
+ header "unordered_map"
+ export *
+}
+module std_unordered_set [system] {
+ header "unordered_set"
+ export *
+}
+module std_utility [system] {
+ header "utility"
+ export *
+}
+module std_valarray [system] {
+ header "valarray"
+ export *
+}
+module std_variant [system] {
+ header "variant"
+ export *
+}
+module std_vector [system] {
+ header "vector"
+ export *
+}
+module std_version [system] {
+ header "version"
+ export *
+}
+
+// C standard library interface wrappers
+module std_cassert [system] {
+ // <cassert>'s use of NDEBUG requires textual inclusion.
+ textual header "cassert"
+}
+module std_ccomplex [system] {
+ header "ccomplex"
+ export *
+}
+module std_cctype [system] {
+ header "cctype"
+ export *
+}
+module std_cerrno [system] {
+ header "cerrno"
+ export *
+}
+module std_cfenv [system] {
+ header "cfenv"
+ export *
+}
+module std_cfloat [system] {
+ header "cfloat"
+ export *
+}
+module std_cinttypes [system] {
+ header "cinttypes"
+ export *
+}
+module std_ciso646 [system] {
+ header "ciso646"
+ export *
+}
+module std_climits [system] {
+ header "climits"
+ export *
+}
+module std_clocale [system] {
+ header "clocale"
+ export *
+}
+module std_cmath [system] {
+ header "cmath"
+ export *
+}
+module std_csetjmp [system] {
+ header "csetjmp"
+ export *
+}
+module std_csignal [system] {
+ header "csignal"
+ export *
+}
+// FIXME: <cstdalign> is missing.
+module std_cstdarg [system] {
+ header "cstdarg"
+ export *
+}
+module std_cstdbool [system] {
+ header "cstdbool"
+ export *
+}
+module std_cstddef [system] {
+ header "cstddef"
+ export *
+}
+module std_cstdint [system] {
+ header "cstdint"
+ export *
+}
+module std_cstdio [system] {
+ header "cstdio"
+ export *
+}
+module std_cstdlib [system] {
+ header "cstdlib"
+ export *
+}
+module std_cstring [system] {
+ header "cstring"
+ export *
+}
+module std_ctgmath [system] {
+ header "ctgmath"
+ export *
+}
+module std_ctime [system] {
+ header "ctime"
+ export *
+}
+module std_cuchar [system] {
+ header "cuchar"
+ export *
+}
+module std_cwchar [system] {
+ header "cwchar"
+ export *
+}
+module std_cwctype [system] {
+ header "cwctype"
+ export *
+}
+
+// C standard library interfaces augmented/replaced in C++
+// <assert.h> provided by C library.
+module std_complex_h [system] {
+ header "complex.h"
+ export *
+}
+module std_ctype_h [system] {
+ header "ctype.h"
+ export *
+}
+module std_errno_h [system] {
+ header "errno.h"
+ export *
+}
+module std_fenv_h [system] {
+ header "fenv.h"
+ export *
+}
+module std_float_h [system] {
+ header "float.h"
+ export *
+}
+module std_inttypes_h [system] {
+ header "inttypes.h"
+ export *
+}
+// <iso646.h> provided by compiler.
+module std_locale_h [system] {
+ header "locale.h"
+ export *
+}
+module std_math_h [system] {
+ header "math.h"
+ export *
+}
+// <setjmp.h> provided by C library.
+// <signal.h> provided by C library.
+// FIXME: <stdalign.h> is missing.
+// <stdarg.h> provided by compiler.
+module std_stdatomic_h [system] {
+ header "stdatomic.h"
+ export *
+}
+module std_stdbool_h [system] {
+ // <stdbool.h>'s __bool_true_false_are_defined macro requires textual inclusion.
+ textual header "stdbool.h"
+ export *
+}
+module std_stddef_h [system] {
+ // <stddef.h>'s __need_* macros require textual inclusion.
+ textual header "stddef.h"
+ export *
+}
+module std_stdint_h [system] {
+ header "stdint.h"
+ export *
+}
+module std_stdio_h [system] {
+ // <stdio.h>'s __need_* macros require textual inclusion.
+ textual header "stdio.h"
+ export *
+}
+module std_stdlib_h [system] {
+ // <stdlib.h>'s __need_* macros require textual inclusion.
+ textual header "stdlib.h"
+ export *
+}
+module std_string_h [system] {
+ header "string.h"
+ export *
+}
+module std_tgmath_h [system] {
+ header "tgmath.h"
+ export *
+}
+module std_uchar_h [system] {
+ header "uchar.h"
+ export *
+}
+// <time.h> provided by C library.
+module std_wchar_h [system] {
+ // <wchar.h>'s __need_* macros require textual inclusion.
+ textual header "wchar.h"
+ export *
+}
+module std_wctype_h [system] {
+ header "wctype.h"
+ export *
+}
+
+// Experimental C++ standard library interfaces
+module std_experimental [system] {
+ module iterator {
+ header "experimental/iterator"
+ export *
+ }
+ module memory {
+ header "experimental/memory"
+ export *
+ }
+ module propagate_const {
+ header "experimental/propagate_const"
+ export *
+ }
+ module simd {
+ module aligned_tag { private header "experimental/__simd/aligned_tag.h" }
+ module declaration { private header "experimental/__simd/declaration.h" }
+ module reference { private header "experimental/__simd/reference.h" }
+ module scalar { private header "experimental/__simd/scalar.h" }
+ module simd { private header "experimental/__simd/simd.h" }
+ module simd_mask { private header "experimental/__simd/simd_mask.h" }
+ module traits { private header "experimental/__simd/traits.h" }
+ module utility { private header "experimental/__simd/utility.h" }
+ module vec_ext { private header "experimental/__simd/vec_ext.h" }
+
+ header "experimental/simd"
+ export *
+ }
+ module type_traits {
+ header "experimental/type_traits"
+ export *
+ }
+ module utility {
+ header "experimental/utility"
+ export *
+ }
+ module __config {
+ textual header "experimental/__config"
+ export *
+ }
+}
+
+// Convenience method to get all of the above modules in a single import statement.
+// Importing only the needed modules is likely to be more performant.
+module std [system] {
+ header "__std_clang_module"
+ export *
+}
+
+// Implementation detail headers that are private to libc++. These modules
+// must not be directly imported.
+module std_private_assert [system] {
+ header "__assert"
+ export *
+}
+module std_private_bit_reference [system] {
+ header "__bit_reference"
+ export *
+}
+module std_private_fwd_bit_reference [system] {
+ header "__fwd/bit_reference.h"
+}
+module std_private_config [system] {
+ textual header "__config"
+ textual header "__configuration/abi.h"
+ textual header "__configuration/availability.h"
+ textual header "__configuration/compiler.h"
+ textual header "__configuration/language.h"
+ textual header "__configuration/platform.h"
+ export *
+}
+module std_private_hash_table [system] {
+ header "__hash_table"
+ export *
+}
+module std_private_locale [system] {
+ header "__locale"
+ export *
+}
+module std_private_mbstate_t [system] {
+ header "__mbstate_t.h"
+ export *
+}
+module std_private_node_handle [system] {
+ header "__node_handle"
+ export *
+}
+module std_private_split_buffer [system] {
+ header "__split_buffer"
+ export *
+}
+module std_private_std_mbstate_t [system] {
+ header "__std_mbstate_t.h"
+ export *
+}
+module std_private_tree [system] {
+ header "__tree"
+ export *
+}
+module std_private_undef_macros [system] {
+ textual header "__undef_macros"
+ export *
+}
+module std_private_verbose_abort [system] {
+ header "__verbose_abort"
+ export *
+}
+
+module std_private_algorithm_adjacent_find [system] { header "__algorithm/adjacent_find.h" }
+module std_private_algorithm_all_of [system] { header "__algorithm/all_of.h" }
+module std_private_algorithm_any_of [system] { header "__algorithm/any_of.h" }
+module std_private_algorithm_binary_search [system] { header "__algorithm/binary_search.h" }
+module std_private_algorithm_clamp [system] { header "__algorithm/clamp.h" }
+module std_private_algorithm_comp [system] { header "__algorithm/comp.h" }
+module std_private_algorithm_comp_ref_type [system] { header "__algorithm/comp_ref_type.h" }
+module std_private_algorithm_copy [system] {
+ header "__algorithm/copy.h"
+ export std_private_algorithm_copy_move_common
+}
+module std_private_algorithm_copy_backward [system] { header "__algorithm/copy_backward.h" }
+module std_private_algorithm_copy_if [system] { header "__algorithm/copy_if.h" }
+module std_private_algorithm_copy_move_common [system] {
+ header "__algorithm/copy_move_common.h"
+ export std_private_type_traits_is_trivially_copyable
+}
+module std_private_algorithm_copy_n [system] { header "__algorithm/copy_n.h" }
+module std_private_algorithm_count [system] { header "__algorithm/count.h" }
+module std_private_algorithm_count_if [system] { header "__algorithm/count_if.h" }
+module std_private_algorithm_equal [system] { header "__algorithm/equal.h" }
+module std_private_algorithm_equal_range [system] { header "__algorithm/equal_range.h" }
+module std_private_algorithm_fill [system] { header "__algorithm/fill.h" }
+module std_private_algorithm_fill_n [system] { header "__algorithm/fill_n.h" }
+module std_private_algorithm_find [system] {
+ header "__algorithm/find.h"
+ export std_private_algorithm_unwrap_iter
+}
+module std_private_algorithm_find_end [system] { header "__algorithm/find_end.h" }
+module std_private_algorithm_find_first_of [system] { header "__algorithm/find_first_of.h" }
+module std_private_algorithm_find_if [system] { header "__algorithm/find_if.h" }
+module std_private_algorithm_find_if_not [system] { header "__algorithm/find_if_not.h" }
+module std_private_algorithm_find_segment_if [system] { header "__algorithm/find_segment_if.h" }
+module std_private_algorithm_fold [system] { header "__algorithm/fold.h" }
+module std_private_algorithm_for_each [system] { header "__algorithm/for_each.h" }
+module std_private_algorithm_for_each_n [system] { header "__algorithm/for_each_n.h" }
+module std_private_algorithm_for_each_segment [system] { header "__algorithm/for_each_segment.h" }
+module std_private_algorithm_generate [system] { header "__algorithm/generate.h" }
+module std_private_algorithm_generate_n [system] { header "__algorithm/generate_n.h" }
+module std_private_algorithm_half_positive [system] { header "__algorithm/half_positive.h" }
+module std_private_algorithm_in_found_result [system] { header "__algorithm/in_found_result.h" }
+module std_private_algorithm_in_fun_result [system] { header "__algorithm/in_fun_result.h" }
+module std_private_algorithm_in_in_out_result [system] { header "__algorithm/in_in_out_result.h" }
+module std_private_algorithm_in_in_result [system] { header "__algorithm/in_in_result.h" }
+module std_private_algorithm_in_out_out_result [system] { header "__algorithm/in_out_out_result.h" }
+module std_private_algorithm_in_out_result [system] { header "__algorithm/in_out_result.h" }
+module std_private_algorithm_includes [system] { header "__algorithm/includes.h" }
+module std_private_algorithm_inplace_merge [system] { header "__algorithm/inplace_merge.h" }
+module std_private_algorithm_is_heap [system] { header "__algorithm/is_heap.h" }
+module std_private_algorithm_is_heap_until [system] { header "__algorithm/is_heap_until.h" }
+module std_private_algorithm_is_partitioned [system] { header "__algorithm/is_partitioned.h" }
+module std_private_algorithm_is_permutation [system] { header "__algorithm/is_permutation.h" }
+module std_private_algorithm_is_sorted [system] { header "__algorithm/is_sorted.h" }
+module std_private_algorithm_is_sorted_until [system] { header "__algorithm/is_sorted_until.h" }
+module std_private_algorithm_iter_swap [system] { header "__algorithm/iter_swap.h" }
+module std_private_algorithm_iterator_operations [system] {
+ header "__algorithm/iterator_operations.h"
+ export *
+}
+module std_private_algorithm_lexicographical_compare [system] { header "__algorithm/lexicographical_compare.h" }
+module std_private_algorithm_lexicographical_compare_three_way [system] { header "__algorithm/lexicographical_compare_three_way.h" }
+module std_private_algorithm_lower_bound [system] { header "__algorithm/lower_bound.h" }
+module std_private_algorithm_make_heap [system] { header "__algorithm/make_heap.h" }
+module std_private_algorithm_make_projected [system] { header "__algorithm/make_projected.h" }
+module std_private_algorithm_max [system] { header "__algorithm/max.h" }
+module std_private_algorithm_max_element [system] { header "__algorithm/max_element.h" }
+module std_private_algorithm_merge [system] { header "__algorithm/merge.h" }
+module std_private_algorithm_min [system] { header "__algorithm/min.h" }
+module std_private_algorithm_min_element [system] { header "__algorithm/min_element.h" }
+module std_private_algorithm_min_max_result [system] { header "__algorithm/min_max_result.h" }
+module std_private_algorithm_minmax [system] {
+ header "__algorithm/minmax.h"
+ export *
+}
+module std_private_algorithm_minmax_element [system] { header "__algorithm/minmax_element.h" }
+module std_private_algorithm_mismatch [system] {
+ header "__algorithm/mismatch.h"
+ export std_private_algorithm_simd_utils
+ export std_private_iterator_aliasing_iterator
+}
+module std_private_algorithm_move [system] { header "__algorithm/move.h" }
+module std_private_algorithm_move_backward [system] { header "__algorithm/move_backward.h" }
+module std_private_algorithm_next_permutation [system] { header "__algorithm/next_permutation.h" }
+module std_private_algorithm_none_of [system] { header "__algorithm/none_of.h" }
+module std_private_algorithm_nth_element [system] { header "__algorithm/nth_element.h" }
+module std_private_algorithm_partial_sort [system] { header "__algorithm/partial_sort.h" }
+module std_private_algorithm_partial_sort_copy [system] { header "__algorithm/partial_sort_copy.h" }
+module std_private_algorithm_partition [system] { header "__algorithm/partition.h" }
+module std_private_algorithm_partition_copy [system] { header "__algorithm/partition_copy.h" }
+module std_private_algorithm_partition_point [system] { header "__algorithm/partition_point.h" }
+module std_private_algorithm_pop_heap [system] { header "__algorithm/pop_heap.h" }
+module std_private_algorithm_prev_permutation [system] { header "__algorithm/prev_permutation.h" }
+module std_private_algorithm_pstl [system] {
+ header "__algorithm/pstl.h"
+ export *
+}
+module std_private_algorithm_push_heap [system] { header "__algorithm/push_heap.h" }
+module std_private_algorithm_ranges_adjacent_find [system] { header "__algorithm/ranges_adjacent_find.h" }
+module std_private_algorithm_ranges_all_of [system] { header "__algorithm/ranges_all_of.h" }
+module std_private_algorithm_ranges_any_of [system] { header "__algorithm/ranges_any_of.h" }
+module std_private_algorithm_ranges_binary_search [system] {
+ header "__algorithm/ranges_binary_search.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_clamp [system] {
+ header "__algorithm/ranges_clamp.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_contains [system] { header "__algorithm/ranges_contains.h" }
+module std_private_algorithm_ranges_contains_subrange [system] { header "__algorithm/ranges_contains_subrange.h" }
+module std_private_algorithm_ranges_copy [system] {
+ header "__algorithm/ranges_copy.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_copy_backward [system] {
+ header "__algorithm/ranges_copy_backward.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_copy_if [system] {
+ header "__algorithm/ranges_copy_if.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_copy_n [system] {
+ header "__algorithm/ranges_copy_n.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_count [system] { header "__algorithm/ranges_count.h" }
+module std_private_algorithm_ranges_count_if [system] { header "__algorithm/ranges_count_if.h" }
+module std_private_algorithm_ranges_ends_with [system] { header "__algorithm/ranges_ends_with.h" }
+module std_private_algorithm_ranges_equal [system] { header "__algorithm/ranges_equal.h" }
+module std_private_algorithm_ranges_equal_range [system] {
+ header "__algorithm/ranges_equal_range.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_fill [system] { header "__algorithm/ranges_fill.h" }
+module std_private_algorithm_ranges_fill_n [system] { header "__algorithm/ranges_fill_n.h" }
+module std_private_algorithm_ranges_find [system] { header "__algorithm/ranges_find.h" }
+module std_private_algorithm_ranges_find_end [system] { header "__algorithm/ranges_find_end.h" }
+module std_private_algorithm_ranges_find_first_of [system] { header "__algorithm/ranges_find_first_of.h" }
+module std_private_algorithm_ranges_find_if [system] { header "__algorithm/ranges_find_if.h" }
+module std_private_algorithm_ranges_find_if_not [system] { header "__algorithm/ranges_find_if_not.h" }
+module std_private_algorithm_ranges_find_last [system] { header "__algorithm/ranges_find_last.h" }
+module std_private_algorithm_ranges_for_each [system] {
+ header "__algorithm/ranges_for_each.h"
+ export std_private_algorithm_in_fun_result
+}
+module std_private_algorithm_ranges_for_each_n [system] {
+ header "__algorithm/ranges_for_each_n.h"
+ export std_private_algorithm_in_fun_result
+}
+module std_private_algorithm_ranges_generate [system] { header "__algorithm/ranges_generate.h" }
+module std_private_algorithm_ranges_generate_n [system] { header "__algorithm/ranges_generate_n.h" }
+module std_private_algorithm_ranges_includes [system] {
+ header "__algorithm/ranges_includes.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_inplace_merge [system] {
+ header "__algorithm/ranges_inplace_merge.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_is_heap [system] {
+ header "__algorithm/ranges_is_heap.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_is_heap_until [system] {
+ header "__algorithm/ranges_is_heap_until.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_is_partitioned [system] { header "__algorithm/ranges_is_partitioned.h" }
+module std_private_algorithm_ranges_is_permutation [system] { header "__algorithm/ranges_is_permutation.h" }
+module std_private_algorithm_ranges_is_sorted [system] {
+ header "__algorithm/ranges_is_sorted.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_is_sorted_until [system] {
+ header "__algorithm/ranges_is_sorted_until.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_iterator_concept [system] { header "__algorithm/ranges_iterator_concept.h" }
+module std_private_algorithm_ranges_lexicographical_compare [system] {
+ header "__algorithm/ranges_lexicographical_compare.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_lower_bound [system] {
+ header "__algorithm/ranges_lower_bound.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_make_heap [system] {
+ header "__algorithm/ranges_make_heap.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_max [system] {
+ header "__algorithm/ranges_max.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_max_element [system] {
+ header "__algorithm/ranges_max_element.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_merge [system] {
+ header "__algorithm/ranges_merge.h"
+ export std_private_algorithm_in_in_out_result
+}
+module std_private_algorithm_ranges_min [system] {
+ header "__algorithm/ranges_min.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_min_element [system] {
+ header "__algorithm/ranges_min_element.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_minmax [system] {
+ header "__algorithm/ranges_minmax.h"
+ export std_private_functional_ranges_operations
+ export std_private_algorithm_min_max_result
+}
+module std_private_algorithm_ranges_minmax_element [system] {
+ header "__algorithm/ranges_minmax_element.h"
+ export std_private_functional_ranges_operations
+ export std_private_algorithm_min_max_result
+}
+module std_private_algorithm_ranges_mismatch [system] {
+ header "__algorithm/ranges_mismatch.h"
+ export std_private_algorithm_in_in_result
+}
+module std_private_algorithm_ranges_move [system] {
+ header "__algorithm/ranges_move.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_move_backward [system] {
+ header "__algorithm/ranges_move_backward.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_next_permutation [system] {
+ header "__algorithm/ranges_next_permutation.h"
+ export std_private_algorithm_in_found_result
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_none_of [system] { header "__algorithm/ranges_none_of.h" }
+module std_private_algorithm_ranges_nth_element [system] {
+ header "__algorithm/ranges_nth_element.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_partial_sort [system] {
+ header "__algorithm/ranges_partial_sort.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_partial_sort_copy [system] {
+ header "__algorithm/ranges_partial_sort_copy.h"
+ export std_private_algorithm_in_out_result
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_partition [system] { header "__algorithm/ranges_partition.h" }
+module std_private_algorithm_ranges_partition_copy [system] { header "__algorithm/ranges_partition_copy.h" }
+module std_private_algorithm_ranges_partition_point [system] { header "__algorithm/ranges_partition_point.h" }
+module std_private_algorithm_ranges_pop_heap [system] {
+ header "__algorithm/ranges_pop_heap.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_prev_permutation [system] {
+ header "__algorithm/ranges_prev_permutation.h"
+ export std_private_algorithm_in_found_result
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_push_heap [system] {
+ header "__algorithm/ranges_push_heap.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_remove [system] { header "__algorithm/ranges_remove.h" }
+module std_private_algorithm_ranges_remove_copy [system] {
+ header "__algorithm/ranges_remove_copy.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_remove_copy_if [system] {
+ header "__algorithm/ranges_remove_copy_if.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_remove_if [system] { header "__algorithm/ranges_remove_if.h" }
+module std_private_algorithm_ranges_replace [system] { header "__algorithm/ranges_replace.h" }
+module std_private_algorithm_ranges_replace_copy [system] {
+ header "__algorithm/ranges_replace_copy.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_replace_copy_if [system] {
+ header "__algorithm/ranges_replace_copy_if.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_replace_if [system] { header "__algorithm/ranges_replace_if.h" }
+module std_private_algorithm_ranges_reverse [system] { header "__algorithm/ranges_reverse.h" }
+module std_private_algorithm_ranges_reverse_copy [system] {
+ header "__algorithm/ranges_reverse_copy.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_rotate [system] { header "__algorithm/ranges_rotate.h" }
+module std_private_algorithm_ranges_rotate_copy [system] {
+ header "__algorithm/ranges_rotate_copy.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_sample [system] { header "__algorithm/ranges_sample.h" }
+module std_private_algorithm_ranges_search [system] { header "__algorithm/ranges_search.h" }
+module std_private_algorithm_ranges_search_n [system] { header "__algorithm/ranges_search_n.h" }
+module std_private_algorithm_ranges_set_difference [system] {
+ header "__algorithm/ranges_set_difference.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_set_intersection [system] {
+ header "__algorithm/ranges_set_intersection.h"
+ export std_private_algorithm_in_in_out_result
+}
+module std_private_algorithm_ranges_set_symmetric_difference [system] {
+ header "__algorithm/ranges_set_symmetric_difference.h"
+ export std_private_algorithm_in_in_out_result
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_set_union [system] {
+ header "__algorithm/ranges_set_union.h"
+ export std_private_algorithm_in_in_out_result
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_shuffle [system] { header "__algorithm/ranges_shuffle.h" }
+module std_private_algorithm_ranges_sort [system] {
+ header "__algorithm/ranges_sort.h"
+ export std_private_algorithm_make_projected
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_sort_heap [system] {
+ header "__algorithm/ranges_sort_heap.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_stable_partition [system] { header "__algorithm/ranges_stable_partition.h" }
+module std_private_algorithm_ranges_stable_sort [system] {
+ header "__algorithm/ranges_stable_sort.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_ranges_starts_with [system] { header "__algorithm/ranges_starts_with.h" }
+module std_private_algorithm_ranges_swap_ranges [system] {
+ header "__algorithm/ranges_swap_ranges.h"
+ export std_private_algorithm_in_in_result
+}
+module std_private_algorithm_ranges_transform [system] {
+ header "__algorithm/ranges_transform.h"
+ export std_private_algorithm_in_in_out_result
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_unique [system] { header "__algorithm/ranges_unique.h" }
+module std_private_algorithm_ranges_unique_copy [system] {
+ header "__algorithm/ranges_unique_copy.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_algorithm_ranges_upper_bound [system] {
+ header "__algorithm/ranges_upper_bound.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_algorithm_remove [system] { header "__algorithm/remove.h" }
+module std_private_algorithm_remove_copy [system] { header "__algorithm/remove_copy.h" }
+module std_private_algorithm_remove_copy_if [system] { header "__algorithm/remove_copy_if.h" }
+module std_private_algorithm_remove_if [system] { header "__algorithm/remove_if.h" }
+module std_private_algorithm_replace [system] { header "__algorithm/replace.h" }
+module std_private_algorithm_replace_copy [system] { header "__algorithm/replace_copy.h" }
+module std_private_algorithm_replace_copy_if [system] { header "__algorithm/replace_copy_if.h" }
+module std_private_algorithm_replace_if [system] { header "__algorithm/replace_if.h" }
+module std_private_algorithm_reverse [system] { header "__algorithm/reverse.h" }
+module std_private_algorithm_reverse_copy [system] { header "__algorithm/reverse_copy.h" }
+module std_private_algorithm_rotate [system] { header "__algorithm/rotate.h" }
+module std_private_algorithm_rotate_copy [system] { header "__algorithm/rotate_copy.h" }
+module std_private_algorithm_sample [system] { header "__algorithm/sample.h" }
+module std_private_algorithm_search [system] { header "__algorithm/search.h" }
+module std_private_algorithm_search_n [system] { header "__algorithm/search_n.h" }
+module std_private_algorithm_set_difference [system] { header "__algorithm/set_difference.h" }
+module std_private_algorithm_set_intersection [system] { header "__algorithm/set_intersection.h" }
+module std_private_algorithm_set_symmetric_difference [system] { header "__algorithm/set_symmetric_difference.h" }
+module std_private_algorithm_set_union [system] { header "__algorithm/set_union.h" }
+module std_private_algorithm_shift_left [system] { header "__algorithm/shift_left.h" }
+module std_private_algorithm_shift_right [system] { header "__algorithm/shift_right.h" }
+module std_private_algorithm_shuffle [system] { header "__algorithm/shuffle.h" }
+module std_private_algorithm_sift_down [system] { header "__algorithm/sift_down.h" }
+module std_private_algorithm_sort [system] {
+ header "__algorithm/sort.h"
+ export std_private_debug_utils_strict_weak_ordering_check
+}
+module std_private_algorithm_simd_utils [system] { header "__algorithm/simd_utils.h" }
+module std_private_algorithm_sort_heap [system] { header "__algorithm/sort_heap.h" }
+module std_private_algorithm_stable_partition [system] { header "__algorithm/stable_partition.h" }
+module std_private_algorithm_stable_sort [system] { header "__algorithm/stable_sort.h" }
+module std_private_algorithm_swap_ranges [system] {
+ header "__algorithm/swap_ranges.h"
+ export std_private_algorithm_iterator_operations
+}
+module std_private_algorithm_three_way_comp_ref_type [system] { header "__algorithm/three_way_comp_ref_type.h" }
+module std_private_algorithm_transform [system] { header "__algorithm/transform.h" }
+module std_private_algorithm_uniform_random_bit_generator_adaptor [system] { header "__algorithm/uniform_random_bit_generator_adaptor.h" }
+module std_private_algorithm_unique [system] { header "__algorithm/unique.h" }
+module std_private_algorithm_unique_copy [system] { header "__algorithm/unique_copy.h" }
+module std_private_algorithm_unwrap_iter [system] {
+ header "__algorithm/unwrap_iter.h"
+ export std_private_iterator_iterator_traits
+}
+module std_private_algorithm_unwrap_range [system] {
+ header "__algorithm/unwrap_range.h"
+ export std_private_utility_pair
+}
+module std_private_algorithm_upper_bound [system] { header "__algorithm/upper_bound.h" }
+
+module std_private_array_array_fwd [system] { header "__fwd/array.h" }
+
+module std_private_atomic_aliases [system] {
+ header "__atomic/aliases.h"
+ export std_private_atomic_atomic
+}
+module std_private_atomic_atomic [system] {
+ header "__atomic/atomic.h"
+ export std_private_atomic_atomic_base
+}
+module std_private_atomic_atomic_base [system] { header "__atomic/atomic_base.h" }
+module std_private_atomic_atomic_flag [system] {
+ header "__atomic/atomic_flag.h"
+ export *
+}
+module std_private_atomic_atomic_init [system] { header "__atomic/atomic_init.h" }
+module std_private_atomic_atomic_lock_free [system] { header "__atomic/atomic_lock_free.h" }
+module std_private_atomic_atomic_ref [system] { header "__atomic/atomic_ref.h" }
+module std_private_atomic_atomic_sync [system] {
+ header "__atomic/atomic_sync.h"
+ export std_private_atomic_to_gcc_order
+}
+module std_private_atomic_check_memory_order [system] { header "__atomic/check_memory_order.h" }
+module std_private_atomic_contention_t [system] { header "__atomic/contention_t.h" }
+module std_private_atomic_cxx_atomic_impl [system] { header "__atomic/cxx_atomic_impl.h" }
+module std_private_atomic_fence [system] { header "__atomic/fence.h" }
+module std_private_atomic_is_always_lock_free [system] { header "__atomic/is_always_lock_free.h" }
+module std_private_atomic_kill_dependency [system] { header "__atomic/kill_dependency.h" }
+module std_private_atomic_memory_order [system] { header "__atomic/memory_order.h" }
+module std_private_atomic_to_gcc_order [system] {
+ header "__atomic/to_gcc_order.h"
+ export std_private_atomic_memory_order
+}
+
+module std_private_bit_bit_cast [system] { header "__bit/bit_cast.h" }
+module std_private_bit_bit_ceil [system] { header "__bit/bit_ceil.h" }
+module std_private_bit_bit_floor [system] { header "__bit/bit_floor.h" }
+module std_private_bit_bit_log2 [system] { header "__bit/bit_log2.h" }
+module std_private_bit_bit_width [system] { header "__bit/bit_width.h" }
+module std_private_bit_blsr [system] { header "__bit/blsr.h" }
+module std_private_bit_byteswap [system] { header "__bit/byteswap.h" }
+module std_private_bit_countl [system] { header "__bit/countl.h" }
+module std_private_bit_countr [system] { header "__bit/countr.h" }
+module std_private_bit_endian [system] { header "__bit/endian.h" }
+module std_private_bit_has_single_bit [system] { header "__bit/has_single_bit.h" }
+module std_private_bit_invert_if [system] { header "__bit/invert_if.h" }
+module std_private_bit_popcount [system] { header "__bit/popcount.h" }
+module std_private_bit_rotate [system] { header "__bit/rotate.h" }
+
+module std_private_charconv_chars_format [system] { header "__charconv/chars_format.h" }
+module std_private_charconv_from_chars_integral [system] { header "__charconv/from_chars_integral.h" }
+module std_private_charconv_from_chars_result [system] { header "__charconv/from_chars_result.h" }
+module std_private_charconv_tables [system] { header "__charconv/tables.h" }
+module std_private_charconv_to_chars [system] { header "__charconv/to_chars.h" }
+module std_private_charconv_to_chars_base_10 [system] { header "__charconv/to_chars_base_10.h" }
+module std_private_charconv_to_chars_floating_point [system] { header "__charconv/to_chars_floating_point.h" }
+module std_private_charconv_to_chars_integral [system] {
+ header "__charconv/to_chars_integral.h"
+ export std_private_charconv_traits
+}
+module std_private_charconv_to_chars_result [system] {
+ header "__charconv/to_chars_result.h"
+ export *
+}
+module std_private_charconv_traits [system] { header "__charconv/traits.h" }
+
+module std_private_chrono_calendar [system] { header "__chrono/calendar.h" }
+module std_private_chrono_concepts [system] { header "__chrono/concepts.h" }
+module std_private_chrono_convert_to_timespec [system] { header "__chrono/convert_to_timespec.h" }
+module std_private_chrono_convert_to_tm [system] { header "__chrono/convert_to_tm.h" }
+module std_private_chrono_day [system] { header "__chrono/day.h" }
+module std_private_chrono_duration [system] {
+ header "__chrono/duration.h"
+ export std_private_type_traits_is_convertible
+}
+module std_private_chrono_exception [system] { header "__chrono/exception.h" }
+module std_private_chrono_file_clock [system] { header "__chrono/file_clock.h" }
+module std_private_chrono_formatter [system] {
+ header "__chrono/formatter.h"
+}
+module std_private_chrono_hh_mm_ss [system] { header "__chrono/hh_mm_ss.h" }
+module std_private_chrono_high_resolution_clock [system] {
+ header "__chrono/high_resolution_clock.h"
+ export std_private_chrono_steady_clock
+ export std_private_chrono_system_clock
+}
+module std_private_chrono_leap_second [system] { header "__chrono/leap_second.h" }
+module std_private_chrono_literals [system] { header "__chrono/literals.h" }
+module std_private_chrono_local_info [system] {
+ header "__chrono/local_info.h"
+ export std_private_chrono_sys_info
+}
+module std_private_chrono_month [system] { header "__chrono/month.h" }
+module std_private_chrono_month_weekday [system] { header "__chrono/month_weekday.h" }
+module std_private_chrono_monthday [system] { header "__chrono/monthday.h" }
+module std_private_chrono_ostream [system] {
+ header "__chrono/ostream.h"
+}
+module std_private_chrono_parser_std_format_spec [system] {
+ header "__chrono/parser_std_format_spec.h"
+}
+module std_private_chrono_statically_widen [system] { header "__chrono/statically_widen.h" }
+module std_private_chrono_steady_clock [system] {
+ header "__chrono/steady_clock.h"
+ export std_private_chrono_time_point
+}
+module std_private_chrono_time_zone [system] {
+ header "__chrono/time_zone.h"
+ export std_private_memory_unique_ptr
+}
+module std_private_chrono_time_zone_link [system] {
+ header "__chrono/time_zone_link.h"
+}
+module std_private_chrono_sys_info [system] {
+ header "__chrono/sys_info.h"
+}
+module std_private_chrono_system_clock [system] {
+ header "__chrono/system_clock.h"
+ export std_private_chrono_time_point
+}
+module std_private_chrono_tzdb [system] {
+ header "__chrono/tzdb.h"
+ export *
+}
+module std_private_chrono_tzdb_list [system] {
+ header "__chrono/tzdb_list.h"
+ export *
+}
+module std_private_chrono_time_point [system] { header "__chrono/time_point.h" }
+module std_private_chrono_weekday [system] { header "__chrono/weekday.h" }
+module std_private_chrono_year [system] { header "__chrono/year.h" }
+module std_private_chrono_year_month [system] { header "__chrono/year_month.h" }
+module std_private_chrono_year_month_day [system] { header "__chrono/year_month_day.h" }
+module std_private_chrono_year_month_weekday [system] { header "__chrono/year_month_weekday.h" }
+module std_private_chrono_zoned_time [system] { header "__chrono/zoned_time.h" }
+
+module std_private_compare_common_comparison_category [system] { header "__compare/common_comparison_category.h" }
+module std_private_compare_compare_partial_order_fallback [system] { header "__compare/compare_partial_order_fallback.h" }
+module std_private_compare_compare_strong_order_fallback [system] { header "__compare/compare_strong_order_fallback.h" }
+module std_private_compare_compare_three_way [system] { header "__compare/compare_three_way.h" }
+module std_private_compare_compare_three_way_result [system] { header "__compare/compare_three_way_result.h" }
+module std_private_compare_compare_weak_order_fallback [system] { header "__compare/compare_weak_order_fallback.h" }
+module std_private_compare_is_eq [system] { header "__compare/is_eq.h" }
+module std_private_compare_ordering [system] { header "__compare/ordering.h" }
+module std_private_compare_partial_order [system] { header "__compare/partial_order.h" }
+module std_private_compare_strong_order [system] { header "__compare/strong_order.h" }
+module std_private_compare_synth_three_way [system] { header "__compare/synth_three_way.h" }
+module std_private_compare_three_way_comparable [system] { header "__compare/three_way_comparable.h" }
+module std_private_compare_weak_order [system] { header "__compare/weak_order.h" }
+
+module std_private_complex_complex_fwd [system] { header "__fwd/complex.h" }
+
+module std_private_concepts_arithmetic [system] { header "__concepts/arithmetic.h" }
+module std_private_concepts_assignable [system] { header "__concepts/assignable.h" }
+module std_private_concepts_boolean_testable [system] { header "__concepts/boolean_testable.h" }
+module std_private_concepts_class_or_enum [system] { header "__concepts/class_or_enum.h" }
+module std_private_concepts_common_reference_with [system] { header "__concepts/common_reference_with.h" }
+module std_private_concepts_common_with [system] { header "__concepts/common_with.h" }
+module std_private_concepts_constructible [system] {
+ header "__concepts/constructible.h"
+ export std_private_concepts_destructible
+}
+module std_private_concepts_convertible_to [system] { header "__concepts/convertible_to.h" }
+module std_private_concepts_copyable [system] { header "__concepts/copyable.h" }
+module std_private_concepts_derived_from [system] { header "__concepts/derived_from.h" }
+module std_private_concepts_destructible [system] {
+ header "__concepts/destructible.h"
+ export std_private_type_traits_is_nothrow_destructible
+}
+module std_private_concepts_different_from [system] { header "__concepts/different_from.h" }
+module std_private_concepts_equality_comparable [system] {
+ header "__concepts/equality_comparable.h"
+ export std_private_type_traits_common_reference
+}
+module std_private_concepts_invocable [system] { header "__concepts/invocable.h" }
+module std_private_concepts_movable [system] {
+ header "__concepts/movable.h"
+ export std_private_type_traits_is_object
+}
+module std_private_concepts_predicate [system] { header "__concepts/predicate.h" }
+module std_private_concepts_regular [system] { header "__concepts/regular.h" }
+module std_private_concepts_relation [system] { header "__concepts/relation.h" }
+module std_private_concepts_same_as [system] {
+ header "__concepts/same_as.h"
+ export std_private_type_traits_is_same
+}
+module std_private_concepts_semiregular [system] { header "__concepts/semiregular.h" }
+module std_private_concepts_swappable [system] { header "__concepts/swappable.h" }
+module std_private_concepts_totally_ordered [system] { header "__concepts/totally_ordered.h" }
+
+module std_private_condition_variable_condition_variable [system] {
+ header "__condition_variable/condition_variable.h"
+ export *
+}
+
+module std_private_coroutine_coroutine_handle [system] { header "__coroutine/coroutine_handle.h" }
+module std_private_coroutine_coroutine_traits [system] { header "__coroutine/coroutine_traits.h" }
+module std_private_coroutine_noop_coroutine_handle [system] { header "__coroutine/noop_coroutine_handle.h" }
+module std_private_coroutine_trivial_awaitables [system] { header "__coroutine/trivial_awaitables.h" }
+
+module std_private_debug_utils_randomize_range [system] { header "__debug_utils/randomize_range.h" }
+module std_private_debug_utils_sanitizers [system] { header "__debug_utils/sanitizers.h" }
+module std_private_debug_utils_strict_weak_ordering_check [system] {
+ header "__debug_utils/strict_weak_ordering_check.h"
+ export std_private_type_traits_is_constant_evaluated
+}
+
+module std_private_deque_fwd [system] { header "__fwd/deque.h" }
+
+module std_private_exception_exception [system] { header "__exception/exception.h" }
+module std_private_exception_exception_ptr [system] {
+ header "__exception/exception_ptr.h"
+ export std_private_exception_operations
+}
+module std_private_exception_nested_exception [system] { header "__exception/nested_exception.h" }
+module std_private_exception_operations [system] { header "__exception/operations.h" }
+module std_private_exception_terminate [system] { header "__exception/terminate.h" }
+
+module std_private_expected_bad_expected_access [system] { header "__expected/bad_expected_access.h" }
+module std_private_expected_expected [system] { header "__expected/expected.h" }
+module std_private_expected_unexpect [system] { header "__expected/unexpect.h" }
+module std_private_expected_unexpected [system] { header "__expected/unexpected.h" }
+
+module std_private_filesystem_copy_options [system] { header "__filesystem/copy_options.h" }
+module std_private_filesystem_directory_entry [system] {
+ header "__filesystem/directory_entry.h"
+ export *
+}
+module std_private_filesystem_directory_iterator [system] {
+ header "__filesystem/directory_iterator.h"
+ export *
+}
+module std_private_filesystem_directory_options [system] { header "__filesystem/directory_options.h" }
+module std_private_filesystem_file_status [system] { header "__filesystem/file_status.h" }
+module std_private_filesystem_file_time_type [system] { header "__filesystem/file_time_type.h" }
+module std_private_filesystem_file_type [system] { header "__filesystem/file_type.h" }
+module std_private_filesystem_filesystem_error [system] {
+ header "__filesystem/filesystem_error.h"
+ export *
+}
+module std_private_filesystem_operations [system] { header "__filesystem/operations.h" }
+module std_private_filesystem_path [system] {
+ header "__filesystem/path.h"
+ export *
+}
+module std_private_filesystem_path_iterator [system] { header "__filesystem/path_iterator.h" }
+module std_private_filesystem_perm_options [system] { header "__filesystem/perm_options.h" }
+module std_private_filesystem_perms [system] { header "__filesystem/perms.h" }
+module std_private_filesystem_recursive_directory_iterator [system] {
+ header "__filesystem/recursive_directory_iterator.h"
+ export *
+}
+module std_private_filesystem_space_info [system] { header "__filesystem/space_info.h" }
+module std_private_filesystem_u8path [system] { header "__filesystem/u8path.h" }
+
+module std_private_format_buffer [system] { header "__format/buffer.h" }
+module std_private_format_concepts [system] { header "__format/concepts.h" }
+module std_private_format_container_adaptor [system] { header "__format/container_adaptor.h" }
+module std_private_format_enable_insertable [system] { header "__format/enable_insertable.h" }
+module std_private_format_escaped_output_table [system] { header "__format/escaped_output_table.h" }
+module std_private_format_extended_grapheme_cluster_table [system] { header "__format/extended_grapheme_cluster_table.h" }
+module std_private_format_format_arg [system] { header "__format/format_arg.h" }
+module std_private_format_format_arg_store [system] { header "__format/format_arg_store.h" }
+module std_private_format_format_args [system] { header "__format/format_args.h" }
+module std_private_format_format_context [system] {
+ header "__format/format_context.h"
+ export *
+}
+module std_private_format_format_error [system] { header "__format/format_error.h" }
+module std_private_format_format_functions [system] {
+ header "__format/format_functions.h"
+ export std_string
+}
+module std_private_format_fwd [system] { header "__fwd/format.h" }
+module std_private_format_format_parse_context [system] { header "__format/format_parse_context.h" }
+module std_private_format_format_string [system] { header "__format/format_string.h" }
+module std_private_format_format_to_n_result [system] {
+ header "__format/format_to_n_result.h"
+ export std_private_iterator_incrementable_traits
+}
+module std_private_format_formatter [system] { header "__format/formatter.h" }
+module std_private_format_formatter_bool [system] { header "__format/formatter_bool.h" }
+module std_private_format_formatter_char [system] { header "__format/formatter_char.h" }
+module std_private_format_formatter_floating_point [system] { header "__format/formatter_floating_point.h" }
+module std_private_format_formatter_integer [system] { header "__format/formatter_integer.h" }
+module std_private_format_formatter_integral [system] { header "__format/formatter_integral.h" }
+module std_private_format_formatter_output [system] { header "__format/formatter_output.h" }
+module std_private_format_formatter_pointer [system] { header "__format/formatter_pointer.h" }
+module std_private_format_formatter_string [system] { header "__format/formatter_string.h" }
+module std_private_format_formatter_tuple [system] { header "__format/formatter_tuple.h" }
+module std_private_format_indic_conjunct_break_table [system] { header "__format/indic_conjunct_break_table.h" }
+module std_private_format_parser_std_format_spec [system] { header "__format/parser_std_format_spec.h" }
+module std_private_format_range_default_formatter [system] { header "__format/range_default_formatter.h" }
+module std_private_format_range_formatter [system] { header "__format/range_formatter.h" }
+module std_private_format_unicode [system] {
+ header "__format/unicode.h"
+ export std_private_format_extended_grapheme_cluster_table
+ export std_private_format_indic_conjunct_break_table
+}
+module std_private_format_width_estimation_table [system] { header "__format/width_estimation_table.h" }
+module std_private_format_write_escaped [system] { header "__format/write_escaped.h" }
+
+module std_private_functional_binary_function [system] { header "__functional/binary_function.h" }
+module std_private_functional_binary_negate [system] { header "__functional/binary_negate.h" }
+module std_private_functional_bind [system] { header "__functional/bind.h" }
+module std_private_functional_bind_back [system] { header "__functional/bind_back.h" }
+module std_private_functional_bind_front [system] { header "__functional/bind_front.h" }
+module std_private_functional_binder1st [system] { header "__functional/binder1st.h" }
+module std_private_functional_binder2nd [system] { header "__functional/binder2nd.h" }
+module std_private_functional_boyer_moore_searcher [system] {
+ header "__functional/boyer_moore_searcher.h"
+ export std_private_memory_shared_ptr
+}
+module std_private_functional_compose [system] {
+ header "__functional/compose.h"
+ export std_private_functional_perfect_forward
+}
+module std_private_functional_default_searcher [system] { header "__functional/default_searcher.h" }
+module std_private_functional_function [system] { header "__functional/function.h" }
+module std_private_functional_hash [system] {
+ header "__functional/hash.h"
+ export std_cstdint
+ export std_private_type_traits_underlying_type
+ export std_private_utility_pair
+}
+module std_private_functional_fwd [system] { header "__fwd/functional.h" }
+module std_private_functional_identity [system] { header "__functional/identity.h" }
+module std_private_functional_invoke [system] {
+ header "__functional/invoke.h"
+ export *
+}
+module std_private_functional_is_transparent [system] { header "__functional/is_transparent.h" }
+module std_private_functional_mem_fn [system] { header "__functional/mem_fn.h" }
+module std_private_functional_mem_fun_ref [system] { header "__functional/mem_fun_ref.h" }
+module std_private_functional_not_fn [system] {
+ header "__functional/not_fn.h"
+ export std_private_functional_perfect_forward
+}
+module std_private_functional_operations [system] { header "__functional/operations.h" }
+module std_private_functional_perfect_forward [system] {
+ header "__functional/perfect_forward.h"
+ export *
+}
+module std_private_functional_pointer_to_binary_function [system] { header "__functional/pointer_to_binary_function.h" }
+module std_private_functional_pointer_to_unary_function [system] { header "__functional/pointer_to_unary_function.h" }
+module std_private_functional_ranges_operations [system] { header "__functional/ranges_operations.h" }
+module std_private_functional_reference_wrapper [system] { header "__functional/reference_wrapper.h" }
+module std_private_functional_unary_function [system] { header "__functional/unary_function.h" }
+module std_private_functional_unary_negate [system] { header "__functional/unary_negate.h" }
+module std_private_functional_weak_result_type [system] { header "__functional/weak_result_type.h" }
+
+module std_private_ios_fpos [system] { header "__ios/fpos.h" }
+
+module std_private_iosfwd_fstream_fwd [system] { header "__fwd/fstream.h" }
+module std_private_iosfwd_ios_fwd [system] { header "__fwd/ios.h" }
+module std_private_iosfwd_istream_fwd [system] { header "__fwd/istream.h" }
+module std_private_iosfwd_ostream_fwd [system] { header "__fwd/ostream.h" }
+module std_private_iosfwd_sstream_fwd [system] { header "__fwd/sstream.h" }
+module std_private_iosfwd_streambuf_fwd [system] { header "__fwd/streambuf.h" }
+
+module std_private_iterator_access [system] { header "__iterator/access.h" }
+module std_private_iterator_advance [system] { header "__iterator/advance.h" }
+module std_private_iterator_aliasing_iterator [system] { header "__iterator/aliasing_iterator.h" }
+module std_private_iterator_back_insert_iterator [system] { header "__iterator/back_insert_iterator.h" }
+module std_private_iterator_bounded_iter [system] { header "__iterator/bounded_iter.h" }
+module std_private_iterator_common_iterator [system] { header "__iterator/common_iterator.h" }
+module std_private_iterator_concepts [system] {
+ header "__iterator/concepts.h"
+ export std_private_concepts_constructible
+ export std_private_concepts_equality_comparable
+ export std_private_concepts_movable
+ export std_private_type_traits_common_reference
+ export std_private_type_traits_is_reference
+ export std_private_type_traits_remove_cvref
+}
+module std_private_iterator_counted_iterator [system] { header "__iterator/counted_iterator.h" }
+module std_private_iterator_cpp17_iterator_concepts [system] { header "__iterator/cpp17_iterator_concepts.h" }
+module std_private_iterator_data [system] { header "__iterator/data.h" }
+module std_private_iterator_default_sentinel [system] { header "__iterator/default_sentinel.h" }
+module std_private_iterator_distance [system] {
+ header "__iterator/distance.h"
+ export std_private_ranges_size
+}
+module std_private_iterator_empty [system] { header "__iterator/empty.h" }
+module std_private_iterator_erase_if_container [system] { header "__iterator/erase_if_container.h" }
+module std_private_iterator_front_insert_iterator [system] { header "__iterator/front_insert_iterator.h" }
+module std_private_iterator_incrementable_traits [system] { header "__iterator/incrementable_traits.h" }
+module std_private_iterator_indirectly_comparable [system] { header "__iterator/indirectly_comparable.h" }
+module std_private_iterator_insert_iterator [system] { header "__iterator/insert_iterator.h" }
+module std_private_iterator_istream_iterator [system] { header "__iterator/istream_iterator.h" }
+module std_private_iterator_istreambuf_iterator [system] { header "__iterator/istreambuf_iterator.h" }
+module std_private_iterator_iter_move [system] { header "__iterator/iter_move.h" }
+module std_private_iterator_iter_swap [system] { header "__iterator/iter_swap.h" }
+module std_private_iterator_iterator [system] { header "__iterator/iterator.h" }
+module std_private_iterator_iterator_traits [system] {
+ header "__iterator/iterator_traits.h"
+ export std_private_type_traits_is_primary_template
+}
+module std_private_iterator_iterator_with_data [system] { header "__iterator/iterator_with_data.h" }
+module std_private_iterator_mergeable [system] {
+ header "__iterator/mergeable.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_iterator_move_iterator [system] { header "__iterator/move_iterator.h" }
+module std_private_iterator_move_sentinel [system] { header "__iterator/move_sentinel.h" }
+module std_private_iterator_next [system] { header "__iterator/next.h" }
+module std_private_iterator_ostream_iterator [system] { header "__iterator/ostream_iterator.h" }
+module std_private_iterator_ostreambuf_iterator [system] {
+ header "__iterator/ostreambuf_iterator.h"
+ export *
+}
+module std_private_iterator_permutable [system] { header "__iterator/permutable.h" }
+module std_private_iterator_prev [system] { header "__iterator/prev.h" }
+module std_private_iterator_projected [system] { header "__iterator/projected.h" }
+module std_private_iterator_ranges_iterator_traits [system] { header "__iterator/ranges_iterator_traits.h" }
+module std_private_iterator_readable_traits [system] { header "__iterator/readable_traits.h" }
+module std_private_iterator_reverse_access [system] { header "__iterator/reverse_access.h" }
+module std_private_iterator_reverse_iterator [system] { header "__iterator/reverse_iterator.h" }
+module std_private_iterator_segmented_iterator [system] { header "__iterator/segmented_iterator.h" }
+module std_private_iterator_size [system] { header "__iterator/size.h" }
+module std_private_iterator_sortable [system] {
+ header "__iterator/sortable.h"
+ export std_private_functional_ranges_operations
+}
+module std_private_iterator_unreachable_sentinel [system] { header "__iterator/unreachable_sentinel.h" }
+module std_private_iterator_wrap_iter [system] { header "__iterator/wrap_iter.h" }
+
+module std_private_locale_locale_base_api_android [system] { textual header "__locale_dir/locale_base_api/android.h" }
+module std_private_locale_locale_base_api_bsd_locale_defaults [system] { textual header "__locale_dir/locale_base_api/bsd_locale_defaults.h" }
+module std_private_locale_locale_base_api_bsd_locale_fallbacks [system] { textual header "__locale_dir/locale_base_api/bsd_locale_fallbacks.h" }
+module std_private_locale_locale_base_api_fuchsia [system] { textual header "__locale_dir/locale_base_api/fuchsia.h" }
+module std_private_locale_locale_base_api_ibm [system] { textual header "__locale_dir/locale_base_api/ibm.h" }
+module std_private_locale_locale_base_api_locale_guard [system] { header "__locale_dir/locale_base_api/locale_guard.h" }
+module std_private_locale_locale_base_api_musl [system] { textual header "__locale_dir/locale_base_api/musl.h" }
+module std_private_locale_locale_base_api_newlib [system] { textual header "__locale_dir/locale_base_api/newlib.h" }
+module std_private_locale_locale_base_api_openbsd [system] { textual header "__locale_dir/locale_base_api/openbsd.h" }
+module std_private_locale_locale_base_api_win32 [system] { textual header "__locale_dir/locale_base_api/win32.h" }
+module std_private_locale_locale_base_api [system] {
+ header "__locale_dir/locale_base_api.h"
+ export *
+}
+
+module std_private_math_abs [system] { header "__math/abs.h" }
+module std_private_math_copysign [system] { header "__math/copysign.h" }
+module std_private_math_error_functions [system] { header "__math/error_functions.h" }
+module std_private_math_exponential_functions [system] { header "__math/exponential_functions.h" }
+module std_private_math_fdim [system] { header "__math/fdim.h" }
+module std_private_math_fma [system] { header "__math/fma.h" }
+module std_private_math_gamma [system] { header "__math/gamma.h" }
+module std_private_math_hyperbolic_functions [system] { header "__math/hyperbolic_functions.h" }
+module std_private_math_hypot [system] { header "__math/hypot.h" }
+module std_private_math_inverse_hyperbolic_functions [system] { header "__math/inverse_hyperbolic_functions.h" }
+module std_private_math_inverse_trigonometric_functions [system] { header "__math/inverse_trigonometric_functions.h" }
+module std_private_math_logarithms [system] { header "__math/logarithms.h" }
+module std_private_math_min_max [system] { header "__math/min_max.h" }
+module std_private_math_modulo [system] { header "__math/modulo.h" }
+module std_private_math_remainder [system] { header "__math/remainder.h" }
+module std_private_math_roots [system] { header "__math/roots.h" }
+module std_private_math_rounding_functions [system] { header "__math/rounding_functions.h" }
+module std_private_math_special_functions [system] { header "__math/special_functions.h" }
+module std_private_math_traits [system] { header "__math/traits.h" }
+module std_private_math_trigonometric_functions [system] { header "__math/trigonometric_functions.h" }
+
+module std_private_mdspan_default_accessor [system] { header "__mdspan/default_accessor.h" }
+module std_private_mdspan_extents [system] {
+ header "__mdspan/extents.h"
+ export *
+}
+module std_private_mdspan_layout_left [system] { header "__mdspan/layout_left.h" }
+module std_private_mdspan_layout_right [system] { header "__mdspan/layout_right.h" }
+module std_private_mdspan_layout_stride [system] { header "__mdspan/layout_stride.h" }
+module std_private_mdspan_mdspan [system] { header "__mdspan/mdspan.h" }
+module std_private_mdspan_mdspan_fwd [system] { header "__fwd/mdspan.h" }
+
+module std_private_memory_addressof [system] { header "__memory/addressof.h" }
+module std_private_memory_align [system] { header "__memory/align.h" }
+module std_private_memory_aligned_alloc [system] { header "__memory/aligned_alloc.h" }
+module std_private_memory_allocate_at_least [system] { header "__memory/allocate_at_least.h" }
+module std_private_memory_allocation_guard [system] { header "__memory/allocation_guard.h" }
+module std_private_memory_allocator [system] { header "__memory/allocator.h" }
+module std_private_memory_allocator_arg_t [system] { header "__memory/allocator_arg_t.h" }
+module std_private_memory_allocator_destructor [system] { header "__memory/allocator_destructor.h" }
+module std_private_memory_allocator_traits [system] { header "__memory/allocator_traits.h" }
+module std_private_memory_assume_aligned [system] { header "__memory/assume_aligned.h" }
+module std_private_memory_auto_ptr [system] { header "__memory/auto_ptr.h" }
+module std_private_memory_builtin_new_allocator [system] {
+ header "__memory/builtin_new_allocator.h"
+ export *
+}
+module std_private_memory_compressed_pair [system] { header "__memory/compressed_pair.h" }
+module std_private_memory_concepts [system] {
+ header "__memory/concepts.h"
+ export std_private_type_traits_remove_reference
+}
+module std_private_memory_construct_at [system] { header "__memory/construct_at.h" }
+module std_private_memory_destruct_n [system] { header "__memory/destruct_n.h" }
+module std_private_memory_fwd [system] { header "__fwd/memory.h" }
+module std_private_memory_inout_ptr [system] { header "__memory/inout_ptr.h" }
+module std_private_memory_out_ptr [system] { header "__memory/out_ptr.h" }
+module std_private_memory_pointer_traits [system] { header "__memory/pointer_traits.h" }
+module std_private_memory_ranges_construct_at [system] { header "__memory/ranges_construct_at.h" }
+module std_private_memory_ranges_uninitialized_algorithms [system] {
+ header "__memory/ranges_uninitialized_algorithms.h"
+ export std_private_algorithm_in_out_result
+}
+module std_private_memory_raw_storage_iterator [system] { header "__memory/raw_storage_iterator.h" }
+module std_private_memory_shared_ptr [system] {
+ header "__memory/shared_ptr.h"
+ export std_private_memory_uninitialized_algorithms
+}
+module std_private_memory_swap_allocator [system] { header "__memory/swap_allocator.h" }
+module std_private_memory_temp_value [system] { header "__memory/temp_value.h" }
+module std_private_memory_temporary_buffer [system] {
+ header "__memory/temporary_buffer.h"
+ export std_private_utility_pair
+}
+module std_private_memory_uninitialized_algorithms [system] {
+ header "__memory/uninitialized_algorithms.h"
+ export std_private_algorithm_copy
+}
+module std_private_memory_unique_ptr [system] {
+ header "__memory/unique_ptr.h"
+ export std_private_type_traits_add_lvalue_reference
+ export std_private_type_traits_is_pointer
+ export std_private_type_traits_type_identity
+}
+module std_private_memory_uses_allocator [system] { header "__memory/uses_allocator.h" }
+module std_private_memory_uses_allocator_construction [system] { header "__memory/uses_allocator_construction.h" }
+module std_private_memory_voidify [system] { header "__memory/voidify.h" }
+
+module std_private_memory_resource_memory_resource [system] { header "__memory_resource/memory_resource.h" }
+module std_private_memory_resource_memory_resource_fwd [system] { header "__fwd/memory_resource.h" }
+module std_private_memory_resource_monotonic_buffer_resource [system] { header "__memory_resource/monotonic_buffer_resource.h" }
+module std_private_memory_resource_polymorphic_allocator [system] { header "__memory_resource/polymorphic_allocator.h" }
+module std_private_memory_resource_pool_options [system] { header "__memory_resource/pool_options.h" }
+module std_private_memory_resource_synchronized_pool_resource [system] {
+ header "__memory_resource/synchronized_pool_resource.h"
+ export *
+}
+module std_private_memory_resource_unsynchronized_pool_resource [system] { header "__memory_resource/unsynchronized_pool_resource.h" }
+
+module std_private_mutex_lock_guard [system] { header "__mutex/lock_guard.h" }
+module std_private_mutex_mutex [system] { header "__mutex/mutex.h" }
+module std_private_mutex_once_flag [system] { header "__mutex/once_flag.h" }
+module std_private_mutex_tag_types [system] { header "__mutex/tag_types.h" }
+module std_private_mutex_unique_lock [system] { header "__mutex/unique_lock.h" }
+
+module std_private_numeric_accumulate [system] { header "__numeric/accumulate.h" }
+module std_private_numeric_adjacent_difference [system] { header "__numeric/adjacent_difference.h" }
+module std_private_numeric_exclusive_scan [system] { header "__numeric/exclusive_scan.h" }
+module std_private_numeric_gcd_lcm [system] { header "__numeric/gcd_lcm.h" }
+module std_private_numeric_inclusive_scan [system] { header "__numeric/inclusive_scan.h" }
+module std_private_numeric_inner_product [system] { header "__numeric/inner_product.h" }
+module std_private_numeric_iota [system] { header "__numeric/iota.h" }
+module std_private_numeric_midpoint [system] { header "__numeric/midpoint.h" }
+module std_private_numeric_partial_sum [system] { header "__numeric/partial_sum.h" }
+module std_private_numeric_pstl [system] {
+ header "__numeric/pstl.h"
+ export *
+}
+module std_private_numeric_reduce [system] { header "__numeric/reduce.h" }
+module std_private_numeric_saturation_arithmetic [system] { header "__numeric/saturation_arithmetic.h" }
+module std_private_numeric_transform_exclusive_scan [system] { header "__numeric/transform_exclusive_scan.h" }
+module std_private_numeric_transform_inclusive_scan [system] { header "__numeric/transform_inclusive_scan.h" }
+module std_private_numeric_transform_reduce [system] { header "__numeric/transform_reduce.h" }
+
+module std_private_pstl_backend [system] {
+ header "__pstl/backend.h"
+ export *
+}
+module std_private_pstl_backend_fwd [system] {
+ header "__pstl/backend_fwd.h"
+ export *
+}
+module std_private_pstl_backends_default [system] {
+ header "__pstl/backends/default.h"
+ export *
+}
+module std_private_pstl_backends_libdispatch [system] {
+ header "__pstl/backends/libdispatch.h"
+ export *
+}
+module std_private_pstl_backends_serial [system] {
+ header "__pstl/backends/serial.h"
+ export *
+}
+module std_private_pstl_backends_std_thread [system] {
+ header "__pstl/backends/std_thread.h"
+ export *
+}
+module std_private_pstl_cpu_algos_any_of [system] { header "__pstl/cpu_algos/any_of.h" }
+module std_private_pstl_cpu_algos_cpu_traits [system] { header "__pstl/cpu_algos/cpu_traits.h" }
+module std_private_pstl_cpu_algos_fill [system] { header "__pstl/cpu_algos/fill.h" }
+module std_private_pstl_cpu_algos_find_if [system] { header "__pstl/cpu_algos/find_if.h" }
+module std_private_pstl_cpu_algos_for_each [system] { header "__pstl/cpu_algos/for_each.h" }
+module std_private_pstl_cpu_algos_merge [system] { header "__pstl/cpu_algos/merge.h" }
+module std_private_pstl_cpu_algos_stable_sort [system] { header "__pstl/cpu_algos/stable_sort.h" }
+module std_private_pstl_cpu_algos_transform [system] { header "__pstl/cpu_algos/transform.h" }
+module std_private_pstl_cpu_algos_transform_reduce [system] { header "__pstl/cpu_algos/transform_reduce.h" }
+module std_private_pstl_dispatch [system] { header "__pstl/dispatch.h" }
+module std_private_pstl_handle_exception [system] { header "__pstl/handle_exception.h" }
+
+module std_private_queue_fwd [system] { header "__fwd/queue.h" }
+
+module std_private_ostream_basic_ostream [system] {
+ header "__ostream/basic_ostream.h"
+ export std_streambuf
+}
+module std_private_ostream_print [system] {
+ header "__ostream/print.h"
+ export std_print
+}
+
+module std_private_random_bernoulli_distribution [system] { header "__random/bernoulli_distribution.h" }
+module std_private_random_binomial_distribution [system] { header "__random/binomial_distribution.h" }
+module std_private_random_cauchy_distribution [system] { header "__random/cauchy_distribution.h" }
+module std_private_random_chi_squared_distribution [system] { header "__random/chi_squared_distribution.h" }
+module std_private_random_clamp_to_integral [system] { header "__random/clamp_to_integral.h" }
+module std_private_random_default_random_engine [system] { header "__random/default_random_engine.h" }
+module std_private_random_discard_block_engine [system] { header "__random/discard_block_engine.h" }
+module std_private_random_discrete_distribution [system] {
+ header "__random/discrete_distribution.h"
+ export *
+}
+module std_private_random_exponential_distribution [system] { header "__random/exponential_distribution.h" }
+module std_private_random_extreme_value_distribution [system] { header "__random/extreme_value_distribution.h" }
+module std_private_random_fisher_f_distribution [system] { header "__random/fisher_f_distribution.h" }
+module std_private_random_gamma_distribution [system] { header "__random/gamma_distribution.h" }
+module std_private_random_generate_canonical [system] { header "__random/generate_canonical.h" }
+module std_private_random_geometric_distribution [system] { header "__random/geometric_distribution.h" }
+module std_private_random_independent_bits_engine [system] { header "__random/independent_bits_engine.h" }
+module std_private_random_is_seed_sequence [system] { header "__random/is_seed_sequence.h" }
+module std_private_random_is_valid [system] { header "__random/is_valid.h" }
+module std_private_random_knuth_b [system] { header "__random/knuth_b.h" }
+module std_private_random_linear_congruential_engine [system] { header "__random/linear_congruential_engine.h" }
+module std_private_random_log2 [system] { header "__random/log2.h" }
+module std_private_random_lognormal_distribution [system] { header "__random/lognormal_distribution.h" }
+module std_private_random_mersenne_twister_engine [system] { header "__random/mersenne_twister_engine.h" }
+module std_private_random_negative_binomial_distribution [system] { header "__random/negative_binomial_distribution.h" }
+module std_private_random_normal_distribution [system] { header "__random/normal_distribution.h" }
+module std_private_random_piecewise_constant_distribution [system] {
+ header "__random/piecewise_constant_distribution.h"
+ export *
+}
+module std_private_random_piecewise_linear_distribution [system] {
+ header "__random/piecewise_linear_distribution.h"
+ export *
+}
+module std_private_random_poisson_distribution [system] { header "__random/poisson_distribution.h" }
+module std_private_random_random_device [system] {
+ header "__random/random_device.h"
+ export *
+}
+module std_private_random_ranlux [system] { header "__random/ranlux.h" }
+module std_private_random_seed_seq [system] {
+ header "__random/seed_seq.h"
+ export *
+}
+module std_private_random_shuffle_order_engine [system] { header "__random/shuffle_order_engine.h" }
+module std_private_random_student_t_distribution [system] { header "__random/student_t_distribution.h" }
+module std_private_random_subtract_with_carry_engine [system] { header "__random/subtract_with_carry_engine.h" }
+module std_private_random_uniform_int_distribution [system] { header "__random/uniform_int_distribution.h" }
+module std_private_random_uniform_random_bit_generator [system] { header "__random/uniform_random_bit_generator.h" }
+module std_private_random_uniform_real_distribution [system] { header "__random/uniform_real_distribution.h" }
+module std_private_random_weibull_distribution [system] { header "__random/weibull_distribution.h" }
+
+module std_private_ranges_access [system] { header "__ranges/access.h" }
+module std_private_ranges_all [system] {
+ header "__ranges/all.h"
+ export std_private_functional_compose
+ export std_private_functional_perfect_forward
+ export std_private_ranges_owning_view
+}
+module std_private_ranges_as_rvalue_view [system] { header "__ranges/as_rvalue_view.h" }
+module std_private_ranges_chunk_by_view [system] { header "__ranges/chunk_by_view.h" }
+module std_private_ranges_common_view [system] { header "__ranges/common_view.h" }
+module std_private_ranges_concepts [system] {
+ header "__ranges/concepts.h"
+ export std_private_iterator_concepts
+}
+module std_private_ranges_container_compatible_range [system] { header "__ranges/container_compatible_range.h" }
+module std_private_ranges_counted [system] {
+ header "__ranges/counted.h"
+ export std_span
+}
+module std_private_ranges_dangling [system] { header "__ranges/dangling.h" }
+module std_private_ranges_data [system] { header "__ranges/data.h" }
+module std_private_ranges_drop_view [system] { header "__ranges/drop_view.h" }
+module std_private_ranges_drop_while_view [system] { header "__ranges/drop_while_view.h" }
+module std_private_ranges_elements_view [system] { header "__ranges/elements_view.h" }
+module std_private_ranges_empty [system] { header "__ranges/empty.h" }
+module std_private_ranges_empty_view [system] { header "__ranges/empty_view.h" }
+module std_private_ranges_enable_borrowed_range [system] { header "__ranges/enable_borrowed_range.h" }
+module std_private_ranges_enable_view [system] { header "__ranges/enable_view.h" }
+module std_private_ranges_filter_view [system] {
+ header "__ranges/filter_view.h"
+ export std_private_ranges_range_adaptor
+}
+module std_private_ranges_from_range [system] { header "__ranges/from_range.h" }
+module std_private_ranges_iota_view [system] { header "__ranges/iota_view.h" }
+module std_private_ranges_istream_view [system] {
+ header "__ranges/istream_view.h"
+}
+module std_private_ranges_join_view [system] {
+ header "__ranges/join_view.h"
+ export std_private_iterator_iterator_with_data
+ export std_private_iterator_segmented_iterator
+}
+module std_private_ranges_lazy_split_view [system] {
+ header "__ranges/lazy_split_view.h"
+ export std_private_ranges_non_propagating_cache
+}
+module std_private_ranges_movable_box [system] { header "__ranges/movable_box.h" }
+module std_private_ranges_non_propagating_cache [system] { header "__ranges/non_propagating_cache.h" }
+module std_private_ranges_owning_view [system] { header "__ranges/owning_view.h" }
+module std_private_ranges_range_adaptor [system] { header "__ranges/range_adaptor.h" }
+module std_private_ranges_rbegin [system] { header "__ranges/rbegin.h" }
+module std_private_ranges_ref_view [system] { header "__ranges/ref_view.h" }
+module std_private_ranges_rend [system] { header "__ranges/rend.h" }
+module std_private_ranges_repeat_view [system] { header "__ranges/repeat_view.h" }
+module std_private_ranges_reverse_view [system] { header "__ranges/reverse_view.h" }
+module std_private_ranges_single_view [system] { header "__ranges/single_view.h" }
+module std_private_ranges_size [system] {
+ header "__ranges/size.h"
+ export std_private_type_traits_make_unsigned
+}
+module std_private_ranges_split_view [system] { header "__ranges/split_view.h" }
+module std_private_ranges_subrange [system] {
+ header "__ranges/subrange.h"
+ export std_private_ranges_subrange_fwd
+}
+module std_private_ranges_subrange_fwd [system] {
+ header "__fwd/subrange.h"
+ export std_private_iterator_concepts
+}
+module std_private_ranges_take_view [system] { header "__ranges/take_view.h" }
+module std_private_ranges_take_while_view [system] { header "__ranges/take_while_view.h" }
+module std_private_ranges_to [system] { header "__ranges/to.h" }
+module std_private_ranges_transform_view [system] {
+ header "__ranges/transform_view.h"
+ export std_private_functional_bind_back
+ export std_private_functional_perfect_forward
+ export std_private_ranges_movable_box
+}
+module std_private_ranges_view_interface [system] { header "__ranges/view_interface.h" }
+module std_private_ranges_views [system] { header "__ranges/views.h" }
+module std_private_ranges_zip_view [system] {
+ header "__ranges/zip_view.h"
+ export std_private_utility_pair
+}
+
+module std_private_span_span_fwd [system] { header "__fwd/span.h" }
+
+module std_private_stack_fwd [system] { header "__fwd/stack.h" }
+
+module std_private_stop_token_atomic_unique_lock [system] { header "__stop_token/atomic_unique_lock.h" }
+module std_private_stop_token_intrusive_list_view [system] { header "__stop_token/intrusive_list_view.h" }
+module std_private_stop_token_intrusive_shared_ptr [system] { header "__stop_token/intrusive_shared_ptr.h" }
+module std_private_stop_token_stop_callback [system] { header "__stop_token/stop_callback.h" }
+module std_private_stop_token_stop_source [system] {
+ header "__stop_token/stop_source.h"
+ export *
+}
+module std_private_stop_token_stop_state [system] {
+ header "__stop_token/stop_state.h"
+ export *
+}
+module std_private_stop_token_stop_token [system] {
+ header "__stop_token/stop_token.h"
+ export *
+}
+
+module std_private_string_char_traits [system] {
+ header "__string/char_traits.h"
+ export *
+}
+module std_private_string_constexpr_c_functions [system] {
+ header "__string/constexpr_c_functions.h"
+ export std_private_type_traits_is_equality_comparable
+}
+module std_private_string_extern_template_lists [system] { header "__string/extern_template_lists.h" }
+module std_private_string_string_fwd [system] { header "__fwd/string.h" }
+
+module std_private_string_view_string_view_fwd [system] { header "__fwd/string_view.h" }
+
+module std_private_system_error_errc [system] { header "__system_error/errc.h" }
+module std_private_system_error_error_category [system] { header "__system_error/error_category.h" }
+module std_private_system_error_error_code [system] {
+ header "__system_error/error_code.h"
+ export std_private_functional_hash
+ export std_private_functional_unary_function
+}
+module std_private_system_error_error_condition [system] {
+ header "__system_error/error_condition.h"
+ export std_private_functional_hash
+ export std_private_functional_unary_function
+}
+module std_private_system_error_system_error [system] { header "__system_error/system_error.h" }
+
+module std_private_thread_formatter [system] { header "__thread/formatter.h" }
+module std_private_thread_id [system] { header "__thread/id.h" }
+module std_private_thread_jthread [system] {
+ header "__thread/jthread.h"
+ export *
+}
+module std_private_thread_poll_with_backoff [system] { header "__thread/poll_with_backoff.h" }
+module std_private_thread_support [system] {
+ header "__thread/support.h"
+ export *
+}
+module std_private_thread_support_c11 [system] { textual header "__thread/support/c11.h" }
+module std_private_thread_support_external [system] { textual header "__thread/support/external.h" }
+module std_private_thread_support_pthread [system] { textual header "__thread/support/pthread.h" }
+module std_private_thread_support_windows [system] { textual header "__thread/support/windows.h" }
+module std_private_thread_this_thread [system] { header "__thread/this_thread.h" }
+module std_private_thread_thread [system] {
+ header "__thread/thread.h"
+ export *
+}
+module std_private_thread_timed_backoff_policy [system] { header "__thread/timed_backoff_policy.h" }
+
+module std_private_tuple_find_index [system] { header "__tuple/find_index.h" }
+module std_private_tuple_ignore [system] { header "__tuple/ignore.h" }
+module std_private_tuple_make_tuple_types [system] { header "__tuple/make_tuple_types.h" }
+module std_private_tuple_tuple_like_no_subrange [system] {
+ header "__tuple/tuple_like_no_subrange.h"
+}
+module std_private_tuple_sfinae_helpers [system] { header "__tuple/sfinae_helpers.h" }
+module std_private_tuple_tuple_element [system] { header "__tuple/tuple_element.h" }
+module std_private_tuple_tuple_fwd [system] { header "__fwd/tuple.h" }
+module std_private_tuple_tuple_indices [system] { header "__tuple/tuple_indices.h" }
+module std_private_tuple_tuple_like [system] {
+ header "__tuple/tuple_like.h"
+ export *
+}
+module std_private_tuple_tuple_like_ext [system] { header "__tuple/tuple_like_ext.h" }
+module std_private_tuple_tuple_size [system] { header "__tuple/tuple_size.h" }
+module std_private_tuple_tuple_types [system] { header "__tuple/tuple_types.h" }
+
+module std_private_type_traits_add_const [system] { header "__type_traits/add_const.h" }
+module std_private_type_traits_add_cv [system] { header "__type_traits/add_cv.h" }
+module std_private_type_traits_add_lvalue_reference [system] {
+ header "__type_traits/add_lvalue_reference.h"
+ export std_private_type_traits_is_referenceable
+}
+module std_private_type_traits_add_pointer [system] { header "__type_traits/add_pointer.h" }
+module std_private_type_traits_add_rvalue_reference [system] { header "__type_traits/add_rvalue_reference.h" }
+module std_private_type_traits_add_volatile [system] { header "__type_traits/add_volatile.h" }
+module std_private_type_traits_aligned_storage [system] { header "__type_traits/aligned_storage.h" }
+module std_private_type_traits_aligned_union [system] { header "__type_traits/aligned_union.h" }
+module std_private_type_traits_alignment_of [system] { header "__type_traits/alignment_of.h" }
+module std_private_type_traits_can_extract_key [system] { header "__type_traits/can_extract_key.h" }
+module std_private_type_traits_common_reference [system] {
+ header "__type_traits/common_reference.h"
+ export std_private_type_traits_remove_cvref
+}
+module std_private_type_traits_common_type [system] {
+ header "__type_traits/common_type.h"
+ export std_private_utility_declval
+}
+module std_private_type_traits_conditional [system] { header "__type_traits/conditional.h" }
+module std_private_type_traits_conjunction [system] { header "__type_traits/conjunction.h" }
+module std_private_type_traits_copy_cv [system] { header "__type_traits/copy_cv.h" }
+module std_private_type_traits_copy_cvref [system] { header "__type_traits/copy_cvref.h" }
+module std_private_type_traits_datasizeof [system] { header "__type_traits/datasizeof.h" }
+module std_private_type_traits_decay [system] {
+ header "__type_traits/decay.h"
+ export std_private_type_traits_add_pointer
+}
+module std_private_type_traits_dependent_type [system] { header "__type_traits/dependent_type.h" }
+module std_private_type_traits_desugars_to [system] { header "__type_traits/desugars_to.h" }
+module std_private_type_traits_disjunction [system] { header "__type_traits/disjunction.h" }
+module std_private_type_traits_enable_if [system] { header "__type_traits/enable_if.h" }
+module std_private_type_traits_extent [system] { header "__type_traits/extent.h" }
+module std_private_type_traits_has_unique_object_representation [system] { header "__type_traits/has_unique_object_representation.h" }
+module std_private_type_traits_has_virtual_destructor [system] { header "__type_traits/has_virtual_destructor.h" }
+module std_private_type_traits_integral_constant [system] { header "__type_traits/integral_constant.h" }
+module std_private_type_traits_invoke [system] {
+ header "__type_traits/invoke.h"
+ export std_private_type_traits_conditional
+ export std_private_type_traits_decay
+ export std_private_type_traits_decay
+ export std_private_type_traits_enable_if
+ export std_private_type_traits_is_base_of
+ export std_private_type_traits_is_core_convertible
+ export std_private_type_traits_is_reference_wrapper
+ export std_private_type_traits_is_same
+ export std_private_type_traits_is_void
+ export std_private_type_traits_nat
+ export std_private_type_traits_remove_cv
+}
+module std_private_type_traits_is_abstract [system] { header "__type_traits/is_abstract.h" }
+module std_private_type_traits_is_aggregate [system] { header "__type_traits/is_aggregate.h" }
+module std_private_type_traits_is_allocator [system] { header "__type_traits/is_allocator.h" }
+module std_private_type_traits_is_always_bitcastable [system] { header "__type_traits/is_always_bitcastable.h" }
+module std_private_type_traits_is_arithmetic [system] {
+ header "__type_traits/is_arithmetic.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_array [system] {
+ header "__type_traits/is_array.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_assignable [system] { header "__type_traits/is_assignable.h" }
+module std_private_type_traits_is_base_of [system] { header "__type_traits/is_base_of.h" }
+module std_private_type_traits_is_bounded_array [system] { header "__type_traits/is_bounded_array.h" }
+module std_private_type_traits_is_callable [system] {
+ header "__type_traits/is_callable.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_char_like_type [system] { header "__type_traits/is_char_like_type.h" }
+module std_private_type_traits_is_class [system] { header "__type_traits/is_class.h" }
+module std_private_type_traits_is_compound [system] { header "__type_traits/is_compound.h" }
+module std_private_type_traits_is_const [system] { header "__type_traits/is_const.h" }
+module std_private_type_traits_is_constant_evaluated [system] { header "__type_traits/is_constant_evaluated.h" }
+module std_private_type_traits_is_constructible [system] { header "__type_traits/is_constructible.h" }
+module std_private_type_traits_is_convertible [system] {
+ header "__type_traits/is_convertible.h"
+ export std_private_type_traits_is_array
+}
+module std_private_type_traits_is_copy_assignable [system] { header "__type_traits/is_copy_assignable.h" }
+module std_private_type_traits_is_copy_constructible [system] { header "__type_traits/is_copy_constructible.h" }
+module std_private_type_traits_is_core_convertible [system] {
+ header "__type_traits/is_core_convertible.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_destructible [system] { header "__type_traits/is_destructible.h" }
+module std_private_type_traits_is_empty [system] { header "__type_traits/is_empty.h" }
+module std_private_type_traits_is_enum [system] {
+ header "__type_traits/is_enum.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_equality_comparable [system] {
+ header "__type_traits/is_equality_comparable.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_execution_policy [system] {
+ header "__type_traits/is_execution_policy.h"
+ export std_private_type_traits_remove_cvref
+}
+module std_private_type_traits_is_final [system] { header "__type_traits/is_final.h" }
+module std_private_type_traits_is_floating_point [system] { header "__type_traits/is_floating_point.h" }
+module std_private_type_traits_is_function [system] { header "__type_traits/is_function.h" }
+module std_private_type_traits_is_fundamental [system] { header "__type_traits/is_fundamental.h" }
+module std_private_type_traits_is_implicitly_default_constructible [system] {
+ header "__type_traits/is_implicitly_default_constructible.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_integral [system] { header "__type_traits/is_integral.h" }
+module std_private_type_traits_is_literal_type [system] { header "__type_traits/is_literal_type.h" }
+module std_private_type_traits_is_member_pointer [system] { header "__type_traits/is_member_pointer.h" }
+module std_private_type_traits_is_nothrow_assignable [system] { header "__type_traits/is_nothrow_assignable.h" }
+module std_private_type_traits_is_nothrow_constructible [system] {
+ header "__type_traits/is_nothrow_constructible.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_nothrow_convertible [system] { header "__type_traits/is_nothrow_convertible.h" }
+module std_private_type_traits_is_nothrow_destructible [system] {
+ header "__type_traits/is_nothrow_destructible.h"
+ export std_private_type_traits_is_destructible
+}
+module std_private_type_traits_is_null_pointer [system] {
+ header "__type_traits/is_null_pointer.h"
+ export std_cstddef
+}
+module std_private_type_traits_is_object [system] {
+ header "__type_traits/is_object.h"
+ export std_private_type_traits_is_scalar
+}
+module std_private_type_traits_is_pod [system] { header "__type_traits/is_pod.h" }
+module std_private_type_traits_is_pointer [system] { header "__type_traits/is_pointer.h" }
+module std_private_type_traits_is_polymorphic [system] { header "__type_traits/is_polymorphic.h" }
+module std_private_type_traits_is_primary_template [system] {
+ header "__type_traits/is_primary_template.h"
+ export std_private_type_traits_enable_if
+}
+module std_private_type_traits_is_reference [system] { header "__type_traits/is_reference.h" }
+module std_private_type_traits_is_reference_wrapper [system] { header "__type_traits/is_reference_wrapper.h" }
+module std_private_type_traits_is_referenceable [system] { header "__type_traits/is_referenceable.h" }
+module std_private_type_traits_is_same [system] {
+ header "__type_traits/is_same.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_scalar [system] {
+ header "__type_traits/is_scalar.h"
+ export std_private_type_traits_is_null_pointer
+}
+module std_private_type_traits_is_signed [system] { header "__type_traits/is_signed.h" }
+module std_private_type_traits_is_signed_integer [system] { header "__type_traits/is_signed_integer.h" }
+module std_private_type_traits_is_specialization [system] { header "__type_traits/is_specialization.h" }
+module std_private_type_traits_is_standard_layout [system] { header "__type_traits/is_standard_layout.h" }
+module std_private_type_traits_is_swappable [system] {
+ header "__type_traits/is_swappable.h"
+ export std_private_type_traits_is_move_constructible
+}
+module std_private_type_traits_is_trivial [system] { header "__type_traits/is_trivial.h" }
+module std_private_type_traits_is_trivially_assignable [system] { header "__type_traits/is_trivially_assignable.h" }
+module std_private_type_traits_is_trivially_constructible [system] { header "__type_traits/is_trivially_constructible.h" }
+module std_private_type_traits_is_trivially_copyable [system] { header "__type_traits/is_trivially_copyable.h" }
+module std_private_type_traits_is_trivially_destructible [system] { header "__type_traits/is_trivially_destructible.h" }
+module std_private_type_traits_is_trivially_lexicographically_comparable [system] { header "__type_traits/is_trivially_lexicographically_comparable.h" }
+module std_private_type_traits_is_trivially_relocatable [system] { header "__type_traits/is_trivially_relocatable.h" }
+module std_private_type_traits_is_unbounded_array [system] { header "__type_traits/is_unbounded_array.h" }
+module std_private_type_traits_is_union [system] { header "__type_traits/is_union.h" }
+module std_private_type_traits_is_unsigned [system] { header "__type_traits/is_unsigned.h" }
+module std_private_type_traits_is_unsigned_integer [system] { header "__type_traits/is_unsigned_integer.h" }
+module std_private_type_traits_is_valid_expansion [system] { header "__type_traits/is_valid_expansion.h" }
+module std_private_type_traits_is_void [system] {
+ header "__type_traits/is_void.h"
+ export std_private_type_traits_integral_constant
+}
+module std_private_type_traits_is_volatile [system] { header "__type_traits/is_volatile.h" }
+module std_private_type_traits_lazy [system] { header "__type_traits/lazy.h" }
+module std_private_type_traits_make_32_64_or_128_bit [system] { header "__type_traits/make_32_64_or_128_bit.h" }
+module std_private_type_traits_make_const_lvalue_ref [system] { header "__type_traits/make_const_lvalue_ref.h" }
+module std_private_type_traits_make_signed [system] { header "__type_traits/make_signed.h" }
+module std_private_type_traits_make_unsigned [system] {
+ header "__type_traits/make_unsigned.h"
+ export std_private_type_traits_is_unsigned
+}
+module std_private_type_traits_maybe_const [system] { header "__type_traits/maybe_const.h" }
+module std_private_type_traits_nat [system] { header "__type_traits/nat.h" }
+module std_private_type_traits_negation [system] { header "__type_traits/negation.h" }
+module std_private_type_traits_noexcept_move_assign_container [system] { header "__type_traits/noexcept_move_assign_container.h" }
+module std_private_type_traits_promote [system] { header "__type_traits/promote.h" }
+module std_private_type_traits_rank [system] { header "__type_traits/rank.h" }
+module std_private_type_traits_remove_all_extents [system] { header "__type_traits/remove_all_extents.h" }
+module std_private_type_traits_remove_const [system] { header "__type_traits/remove_const.h" }
+module std_private_type_traits_remove_const_ref [system] { header "__type_traits/remove_const_ref.h" }
+module std_private_type_traits_remove_cv [system] {
+ header "__type_traits/remove_cv.h"
+ export std_private_type_traits_remove_const
+ export std_private_type_traits_remove_volatile
+}
+module std_private_type_traits_remove_cvref [system] { header "__type_traits/remove_cvref.h" }
+module std_private_type_traits_remove_extent [system] { header "__type_traits/remove_extent.h" }
+module std_private_type_traits_remove_pointer [system] { header "__type_traits/remove_pointer.h" }
+module std_private_type_traits_remove_reference [system] { header "__type_traits/remove_reference.h" }
+module std_private_type_traits_remove_volatile [system] { header "__type_traits/remove_volatile.h" }
+module std_private_type_traits_result_of [system] { header "__type_traits/result_of.h" }
+module std_private_type_traits_strip_signature [system] { header "__type_traits/strip_signature.h" }
+module std_private_type_traits_type_identity [system] { header "__type_traits/type_identity.h" }
+module std_private_type_traits_type_list [system] { header "__type_traits/type_list.h" }
+module std_private_type_traits_underlying_type [system] {
+ header "__type_traits/underlying_type.h"
+ export std_private_type_traits_is_enum
+}
+module std_private_type_traits_unwrap_ref [system] { header "__type_traits/unwrap_ref.h" }
+module std_private_type_traits_void_t [system] { header "__type_traits/void_t.h" }
+
+module std_private_utility_as_const [system] { header "__utility/as_const.h" }
+module std_private_utility_as_lvalue [system] { header "__utility/as_lvalue.h" }
+module std_private_utility_auto_cast [system] {
+ header "__utility/auto_cast.h"
+ export std_private_type_traits_decay
+}
+module std_private_utility_cmp [system] {
+ header "__utility/cmp.h"
+ export std_private_type_traits_make_unsigned
+}
+module std_private_utility_convert_to_integral [system] { header "__utility/convert_to_integral.h" }
+module std_private_utility_declval [system] { header "__utility/declval.h" }
+module std_private_utility_empty [system] { header "__utility/empty.h" }
+module std_private_utility_exception_guard [system] { header "__utility/exception_guard.h" }
+module std_private_utility_exchange [system] { header "__utility/exchange.h" }
+module std_private_utility_forward [system] { header "__utility/forward.h" }
+module std_private_utility_forward_like [system] { header "__utility/forward_like.h" }
+module std_private_utility_in_place [system] { header "__utility/in_place.h" }
+module std_private_utility_integer_sequence [system] { header "__utility/integer_sequence.h" }
+module std_private_utility_is_pointer_in_range [system] { header "__utility/is_pointer_in_range.h" }
+module std_private_utility_is_valid_range [system] { header "__utility/is_valid_range.h" }
+module std_private_utility_move [system] {
+ header "__utility/move.h"
+ export std_private_type_traits_is_copy_constructible
+ export std_private_type_traits_is_nothrow_move_constructible
+ export std_private_type_traits_remove_reference
+}
+module std_private_utility_no_destroy [system] { header "__utility/no_destroy.h" }
+module std_private_utility_pair [system] {
+ header "__utility/pair.h"
+ export std_private_ranges_subrange_fwd
+ export std_private_tuple_pair_like
+ export std_private_type_traits_is_assignable
+ export std_private_type_traits_is_constructible
+ export std_private_type_traits_is_convertible
+ export std_private_type_traits_is_copy_assignable
+ export std_private_type_traits_is_move_assignable
+ export std_private_type_traits_is_nothrow_copy_constructible
+ export std_private_type_traits_is_nothrow_default_constructible
+ export std_private_type_traits_is_nothrow_move_assignable
+ export std_private_utility_pair_fwd
+}
+module std_private_utility_pair_fwd [system] { header "__fwd/pair.h" }
+module std_private_utility_piecewise_construct [system] { header "__utility/piecewise_construct.h" }
+module std_private_utility_priority_tag [system] { header "__utility/priority_tag.h" }
+module std_private_utility_private_constructor_tag [system] { header "__utility/private_constructor_tag.h" }
+module std_private_utility_rel_ops [system] { header "__utility/rel_ops.h" }
+module std_private_utility_small_buffer [system] { header "__utility/small_buffer.h" }
+module std_private_utility_swap [system] {
+ header "__utility/swap.h"
+ export std_private_type_traits_is_swappable
+}
+module std_private_utility_to_underlying [system] { header "__utility/to_underlying.h" }
+module std_private_utility_unreachable [system] { header "__utility/unreachable.h" }
+
+module std_private_variant_monostate [system] { header "__variant/monostate.h" }
+
+module std_private_vector_fwd [system] { header "__fwd/vector.h" }
diff --git a/libcxx/include/__cxx03/mutex b/libcxx/include/__cxx03/mutex
new file mode 100644
index 00000000000000..02c52dd72f02b0
--- /dev/null
+++ b/libcxx/include/__cxx03/mutex
@@ -0,0 +1,516 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_MUTEX
+#define _LIBCPP_MUTEX
+
+/*
+ mutex synopsis
+
+namespace std
+{
+
+class mutex
+{
+public:
+ constexpr mutex() noexcept;
+ ~mutex();
+
+ mutex(const mutex&) = delete;
+ mutex& operator=(const mutex&) = delete;
+
+ void lock();
+ bool try_lock();
+ void unlock();
+
+ typedef pthread_mutex_t* native_handle_type;
+ native_handle_type native_handle();
+};
+
+class recursive_mutex
+{
+public:
+ recursive_mutex();
+ ~recursive_mutex();
+
+ recursive_mutex(const recursive_mutex&) = delete;
+ recursive_mutex& operator=(const recursive_mutex&) = delete;
+
+ void lock();
+ bool try_lock() noexcept;
+ void unlock();
+
+ typedef pthread_mutex_t* native_handle_type;
+ native_handle_type native_handle();
+};
+
+class timed_mutex
+{
+public:
+ timed_mutex();
+ ~timed_mutex();
+
+ timed_mutex(const timed_mutex&) = delete;
+ timed_mutex& operator=(const timed_mutex&) = delete;
+
+ void lock();
+ bool try_lock();
+ template <class Rep, class Period>
+ bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
+ template <class Clock, class Duration>
+ bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
+ void unlock();
+};
+
+class recursive_timed_mutex
+{
+public:
+ recursive_timed_mutex();
+ ~recursive_timed_mutex();
+
+ recursive_timed_mutex(const recursive_timed_mutex&) = delete;
+ recursive_timed_mutex& operator=(const recursive_timed_mutex&) = delete;
+
+ void lock();
+ bool try_lock() noexcept;
+ template <class Rep, class Period>
+ bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
+ template <class Clock, class Duration>
+ bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
+ void unlock();
+};
+
+struct defer_lock_t { explicit defer_lock_t() = default; };
+struct try_to_lock_t { explicit try_to_lock_t() = default; };
+struct adopt_lock_t { explicit adopt_lock_t() = default; };
+
+inline constexpr defer_lock_t defer_lock{};
+inline constexpr try_to_lock_t try_to_lock{};
+inline constexpr adopt_lock_t adopt_lock{};
+
+template <class Mutex>
+class lock_guard
+{
+public:
+ typedef Mutex mutex_type;
+
+ explicit lock_guard(mutex_type& m);
+ lock_guard(mutex_type& m, adopt_lock_t);
+ ~lock_guard();
+
+ lock_guard(lock_guard const&) = delete;
+ lock_guard& operator=(lock_guard const&) = delete;
+};
+
+template <class... MutexTypes>
+class scoped_lock // C++17
+{
+public:
+ using mutex_type = Mutex; // Only if sizeof...(MutexTypes) == 1
+
+ explicit scoped_lock(MutexTypes&... m);
+ scoped_lock(adopt_lock_t, MutexTypes&... m);
+ ~scoped_lock();
+ scoped_lock(scoped_lock const&) = delete;
+ scoped_lock& operator=(scoped_lock const&) = delete;
+private:
+ tuple<MutexTypes&...> pm; // exposition only
+};
+
+template <class Mutex>
+class unique_lock
+{
+public:
+ typedef Mutex mutex_type;
+ unique_lock() noexcept;
+ explicit unique_lock(mutex_type& m);
+ unique_lock(mutex_type& m, defer_lock_t) noexcept;
+ unique_lock(mutex_type& m, try_to_lock_t);
+ unique_lock(mutex_type& m, adopt_lock_t);
+ template <class Clock, class Duration>
+ unique_lock(mutex_type& m, const chrono::time_point<Clock, Duration>& abs_time);
+ template <class Rep, class Period>
+ unique_lock(mutex_type& m, const chrono::duration<Rep, Period>& rel_time);
+ ~unique_lock();
+
+ unique_lock(unique_lock const&) = delete;
+ unique_lock& operator=(unique_lock const&) = delete;
+
+ unique_lock(unique_lock&& u) noexcept;
+ unique_lock& operator=(unique_lock&& u) noexcept;
+
+ void lock();
+ bool try_lock();
+
+ template <class Rep, class Period>
+ bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
+ template <class Clock, class Duration>
+ bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
+
+ void unlock();
+
+ void swap(unique_lock& u) noexcept;
+ mutex_type* release() noexcept;
+
+ bool owns_lock() const noexcept;
+ explicit operator bool () const noexcept;
+ mutex_type* mutex() const noexcept;
+};
+
+template <class Mutex>
+ void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept;
+
+template <class L1, class L2, class... L3>
+ int try_lock(L1&, L2&, L3&...);
+template <class L1, class L2, class... L3>
+ void lock(L1&, L2&, L3&...);
+
+struct once_flag
+{
+ constexpr once_flag() noexcept;
+
+ once_flag(const once_flag&) = delete;
+ once_flag& operator=(const once_flag&) = delete;
+};
+
+template<class Callable, class ...Args>
+ void call_once(once_flag& flag, Callable&& func, Args&&... args);
+
+} // std
+
+*/
+
+#include <__chrono/steady_clock.h>
+#include <__chrono/time_point.h>
+#include <__condition_variable/condition_variable.h>
+#include <__config>
+#include <__memory/shared_ptr.h>
+#include <__mutex/lock_guard.h>
+#include <__mutex/mutex.h>
+#include <__mutex/once_flag.h>
+#include <__mutex/tag_types.h>
+#include <__mutex/unique_lock.h>
+#include <__thread/id.h>
+#include <__thread/support.h>
+#include <__utility/forward.h>
+#include <cstddef>
+#include <limits>
+#ifndef _LIBCPP_CXX03_LANG
+# include <tuple>
+#endif
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+
+class _LIBCPP_EXPORTED_FROM_ABI recursive_mutex {
+ __libcpp_recursive_mutex_t __m_;
+
+public:
+ recursive_mutex();
+ ~recursive_mutex();
+
+ recursive_mutex(const recursive_mutex&) = delete;
+ recursive_mutex& operator=(const recursive_mutex&) = delete;
+
+ void lock();
+ bool try_lock() _NOEXCEPT;
+ void unlock() _NOEXCEPT;
+
+ typedef __libcpp_recursive_mutex_t* native_handle_type;
+
+ _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() { return &__m_; }
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI timed_mutex {
+ mutex __m_;
+ condition_variable __cv_;
+ bool __locked_;
+
+public:
+ timed_mutex();
+ ~timed_mutex();
+
+ timed_mutex(const timed_mutex&) = delete;
+ timed_mutex& operator=(const timed_mutex&) = delete;
+
+public:
+ void lock();
+ bool try_lock() _NOEXCEPT;
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI bool try_lock_for(const chrono::duration<_Rep, _Period>& __d) {
+ return try_lock_until(chrono::steady_clock::now() + __d);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS bool
+ try_lock_until(const chrono::time_point<_Clock, _Duration>& __t);
+ void unlock() _NOEXCEPT;
+};
+
+template <class _Clock, class _Duration>
+bool timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) {
+ using namespace chrono;
+ unique_lock<mutex> __lk(__m_);
+ bool __no_timeout = _Clock::now() < __t;
+ while (__no_timeout && __locked_)
+ __no_timeout = __cv_.wait_until(__lk, __t) == cv_status::no_timeout;
+ if (!__locked_) {
+ __locked_ = true;
+ return true;
+ }
+ return false;
+}
+
+class _LIBCPP_EXPORTED_FROM_ABI recursive_timed_mutex {
+ mutex __m_;
+ condition_variable __cv_;
+ size_t __count_;
+ __thread_id __id_;
+
+public:
+ recursive_timed_mutex();
+ ~recursive_timed_mutex();
+
+ recursive_timed_mutex(const recursive_timed_mutex&) = delete;
+ recursive_timed_mutex& operator=(const recursive_timed_mutex&) = delete;
+
+ void lock();
+ bool try_lock() _NOEXCEPT;
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI bool try_lock_for(const chrono::duration<_Rep, _Period>& __d) {
+ return try_lock_until(chrono::steady_clock::now() + __d);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS bool
+ try_lock_until(const chrono::time_point<_Clock, _Duration>& __t);
+ void unlock() _NOEXCEPT;
+};
+
+template <class _Clock, class _Duration>
+bool recursive_timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) {
+ using namespace chrono;
+ __thread_id __id = this_thread::get_id();
+ unique_lock<mutex> __lk(__m_);
+ if (__id == __id_) {
+ if (__count_ == numeric_limits<size_t>::max())
+ return false;
+ ++__count_;
+ return true;
+ }
+ bool __no_timeout = _Clock::now() < __t;
+ while (__no_timeout && __count_ != 0)
+ __no_timeout = __cv_.wait_until(__lk, __t) == cv_status::no_timeout;
+ if (__count_ == 0) {
+ __count_ = 1;
+ __id_ = __id;
+ return true;
+ }
+ return false;
+}
+
+template <class _L0, class _L1>
+_LIBCPP_HIDE_FROM_ABI int try_lock(_L0& __l0, _L1& __l1) {
+ unique_lock<_L0> __u0(__l0, try_to_lock_t());
+ if (__u0.owns_lock()) {
+ if (__l1.try_lock()) {
+ __u0.release();
+ return -1;
+ } else
+ return 1;
+ }
+ return 0;
+}
+
+# ifndef _LIBCPP_CXX03_LANG
+
+template <class _L0, class _L1, class _L2, class... _L3>
+_LIBCPP_HIDE_FROM_ABI int try_lock(_L0& __l0, _L1& __l1, _L2& __l2, _L3&... __l3) {
+ int __r = 0;
+ unique_lock<_L0> __u0(__l0, try_to_lock);
+ if (__u0.owns_lock()) {
+ __r = std::try_lock(__l1, __l2, __l3...);
+ if (__r == -1)
+ __u0.release();
+ else
+ ++__r;
+ }
+ return __r;
+}
+
+# endif // _LIBCPP_CXX03_LANG
+
+template <class _L0, class _L1>
+_LIBCPP_HIDE_FROM_ABI void lock(_L0& __l0, _L1& __l1) {
+ while (true) {
+ {
+ unique_lock<_L0> __u0(__l0);
+ if (__l1.try_lock()) {
+ __u0.release();
+ break;
+ }
+ }
+ __libcpp_thread_yield();
+ {
+ unique_lock<_L1> __u1(__l1);
+ if (__l0.try_lock()) {
+ __u1.release();
+ break;
+ }
+ }
+ __libcpp_thread_yield();
+ }
+}
+
+# ifndef _LIBCPP_CXX03_LANG
+
+template <class _L0, class _L1, class _L2, class... _L3>
+void __lock_first(int __i, _L0& __l0, _L1& __l1, _L2& __l2, _L3&... __l3) {
+ while (true) {
+ switch (__i) {
+ case 0: {
+ unique_lock<_L0> __u0(__l0);
+ __i = std::try_lock(__l1, __l2, __l3...);
+ if (__i == -1) {
+ __u0.release();
+ return;
+ }
+ }
+ ++__i;
+ __libcpp_thread_yield();
+ break;
+ case 1: {
+ unique_lock<_L1> __u1(__l1);
+ __i = std::try_lock(__l2, __l3..., __l0);
+ if (__i == -1) {
+ __u1.release();
+ return;
+ }
+ }
+ if (__i == sizeof...(_L3) + 1)
+ __i = 0;
+ else
+ __i += 2;
+ __libcpp_thread_yield();
+ break;
+ default:
+ std::__lock_first(__i - 2, __l2, __l3..., __l0, __l1);
+ return;
+ }
+ }
+}
+
+template <class _L0, class _L1, class _L2, class... _L3>
+inline _LIBCPP_HIDE_FROM_ABI void lock(_L0& __l0, _L1& __l1, _L2& __l2, _L3&... __l3) {
+ std::__lock_first(0, __l0, __l1, __l2, __l3...);
+}
+
+# endif // _LIBCPP_CXX03_LANG
+
+# if _LIBCPP_STD_VER >= 17
+template <class... _Mutexes>
+class _LIBCPP_TEMPLATE_VIS scoped_lock;
+
+template <>
+class _LIBCPP_TEMPLATE_VIS scoped_lock<> {
+public:
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI explicit scoped_lock() {}
+ ~scoped_lock() = default;
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI explicit scoped_lock(adopt_lock_t) {}
+
+ scoped_lock(scoped_lock const&) = delete;
+ scoped_lock& operator=(scoped_lock const&) = delete;
+};
+
+template <class _Mutex>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_THREAD_SAFETY_ANNOTATION(scoped_lockable) scoped_lock<_Mutex> {
+public:
+ typedef _Mutex mutex_type;
+
+private:
+ mutex_type& __m_;
+
+public:
+ [[nodiscard]]
+ _LIBCPP_HIDE_FROM_ABI explicit scoped_lock(mutex_type& __m) _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability(__m))
+ : __m_(__m) {
+ __m_.lock();
+ }
+
+ ~scoped_lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability()) { __m_.unlock(); }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI explicit scoped_lock(adopt_lock_t, mutex_type& __m)
+ _LIBCPP_THREAD_SAFETY_ANNOTATION(requires_capability(__m))
+ : __m_(__m) {}
+
+ scoped_lock(scoped_lock const&) = delete;
+ scoped_lock& operator=(scoped_lock const&) = delete;
+};
+
+template <class... _MArgs>
+class _LIBCPP_TEMPLATE_VIS scoped_lock {
+ static_assert(sizeof...(_MArgs) > 1, "At least 2 lock types required");
+ typedef tuple<_MArgs&...> _MutexTuple;
+
+public:
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI explicit scoped_lock(_MArgs&... __margs) : __t_(__margs...) {
+ std::lock(__margs...);
+ }
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI scoped_lock(adopt_lock_t, _MArgs&... __margs) : __t_(__margs...) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~scoped_lock() {
+ typedef typename __make_tuple_indices<sizeof...(_MArgs)>::type _Indices;
+ __unlock_unpack(_Indices{}, __t_);
+ }
+
+ scoped_lock(scoped_lock const&) = delete;
+ scoped_lock& operator=(scoped_lock const&) = delete;
+
+private:
+ template <size_t... _Indx>
+ _LIBCPP_HIDE_FROM_ABI static void __unlock_unpack(__tuple_indices<_Indx...>, _MutexTuple& __mt) {
+ (std::get<_Indx>(__mt).unlock(), ...);
+ }
+
+ _MutexTuple __t_;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(scoped_lock);
+
+# endif // _LIBCPP_STD_VER >= 17
+#endif // !_LIBCPP_HAS_NO_THREADS
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstdlib>
+# include <cstring>
+# include <ctime>
+# include <initializer_list>
+# include <iosfwd>
+# include <new>
+# include <stdexcept>
+# include <system_error>
+# include <type_traits>
+# include <typeinfo>
+#endif
+
+#endif // _LIBCPP_MUTEX
diff --git a/libcxx/include/__cxx03/new b/libcxx/include/__cxx03/new
new file mode 100644
index 00000000000000..214dbc398530bb
--- /dev/null
+++ b/libcxx/include/__cxx03/new
@@ -0,0 +1,362 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_NEW
+#define _LIBCPP_NEW
+
+/*
+ new synopsis
+
+namespace std
+{
+
+class bad_alloc
+ : public exception
+{
+public:
+ bad_alloc() noexcept;
+ bad_alloc(const bad_alloc&) noexcept;
+ bad_alloc& operator=(const bad_alloc&) noexcept;
+ virtual const char* what() const noexcept;
+};
+
+class bad_array_new_length : public bad_alloc // C++14
+{
+public:
+ bad_array_new_length() noexcept;
+};
+
+enum class align_val_t : size_t {}; // C++17
+
+struct destroying_delete_t { // C++20
+ explicit destroying_delete_t() = default;
+};
+inline constexpr destroying_delete_t destroying_delete{}; // C++20
+
+struct nothrow_t { explicit nothrow_t() = default; };
+extern const nothrow_t nothrow;
+typedef void (*new_handler)();
+new_handler set_new_handler(new_handler new_p) noexcept;
+new_handler get_new_handler() noexcept;
+
+// 21.6.4, pointer optimization barrier
+template <class T> [[nodiscard]] constexpr T* launder(T* p) noexcept; // C++17, nodiscard since C++20
+} // std
+
+void* operator new(std::size_t size); // replaceable, nodiscard in C++20
+void* operator new(std::size_t size, std::align_val_t alignment); // replaceable, C++17, nodiscard in C++20
+void* operator new(std::size_t size, const std::nothrow_t&) noexcept; // replaceable, nodiscard in C++20
+void* operator new(std::size_t size, std::align_val_t alignment,
+ const std::nothrow_t&) noexcept; // replaceable, C++17, nodiscard in C++20
+void operator delete(void* ptr) noexcept; // replaceable
+void operator delete(void* ptr, std::size_t size) noexcept; // replaceable, C++14
+void operator delete(void* ptr, std::align_val_t alignment) noexcept; // replaceable, C++17
+void operator delete(void* ptr, std::size_t size,
+ std::align_val_t alignment) noexcept; // replaceable, C++17
+void operator delete(void* ptr, const std::nothrow_t&) noexcept; // replaceable
+void operator delete(void* ptr, std:align_val_t alignment,
+ const std::nothrow_t&) noexcept; // replaceable, C++17
+
+void* operator new[](std::size_t size); // replaceable, nodiscard in C++20
+void* operator new[](std::size_t size,
+ std::align_val_t alignment) noexcept; // replaceable, C++17, nodiscard in C++20
+void* operator new[](std::size_t size, const std::nothrow_t&) noexcept; // replaceable, nodiscard in C++20
+void* operator new[](std::size_t size, std::align_val_t alignment,
+ const std::nothrow_t&) noexcept; // replaceable, C++17, nodiscard in C++20
+void operator delete[](void* ptr) noexcept; // replaceable
+void operator delete[](void* ptr, std::size_t size) noexcept; // replaceable, C++14
+void operator delete[](void* ptr,
+ std::align_val_t alignment) noexcept; // replaceable, C++17
+void operator delete[](void* ptr, std::size_t size,
+ std::align_val_t alignment) noexcept; // replaceable, C++17
+void operator delete[](void* ptr, const std::nothrow_t&) noexcept; // replaceable
+void operator delete[](void* ptr, std::align_val_t alignment,
+ const std::nothrow_t&) noexcept; // replaceable, C++17
+
+void* operator new (std::size_t size, void* ptr) noexcept; // nodiscard in C++20
+void* operator new[](std::size_t size, void* ptr) noexcept; // nodiscard in C++20
+void operator delete (void* ptr, void*) noexcept;
+void operator delete[](void* ptr, void*) noexcept;
+
+*/
+
+#include <__config>
+#include <__exception/exception.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cv.h>
+#include <__verbose_abort>
+#include <cstddef>
+#include <version>
+
+#if defined(_LIBCPP_ABI_VCRUNTIME)
+# include <new.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(__cpp_sized_deallocation) || __cpp_sized_deallocation < 201309L
+# define _LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION
+#endif
+
+#if !defined(_LIBCPP_BUILDING_LIBRARY) && _LIBCPP_STD_VER < 14 && defined(_LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION)
+# define _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
+#endif
+
+#if defined(_LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION) || defined(_LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION)
+# define _LIBCPP_HAS_NO_SIZED_DEALLOCATION
+#endif
+
+namespace std // purposefully not using versioning namespace
+{
+
+#if !defined(_LIBCPP_ABI_VCRUNTIME)
+struct _LIBCPP_EXPORTED_FROM_ABI nothrow_t {
+ explicit nothrow_t() = default;
+};
+extern _LIBCPP_EXPORTED_FROM_ABI const nothrow_t nothrow;
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_alloc : public exception {
+public:
+ bad_alloc() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI bad_alloc(const bad_alloc&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_alloc& operator=(const bad_alloc&) _NOEXCEPT = default;
+ ~bad_alloc() _NOEXCEPT override;
+ const char* what() const _NOEXCEPT override;
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_array_new_length : public bad_alloc {
+public:
+ bad_array_new_length() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI bad_array_new_length(const bad_array_new_length&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_array_new_length& operator=(const bad_array_new_length&) _NOEXCEPT = default;
+ ~bad_array_new_length() _NOEXCEPT override;
+ const char* what() const _NOEXCEPT override;
+};
+
+typedef void (*new_handler)();
+_LIBCPP_EXPORTED_FROM_ABI new_handler set_new_handler(new_handler) _NOEXCEPT;
+_LIBCPP_EXPORTED_FROM_ABI new_handler get_new_handler() _NOEXCEPT;
+
+#elif defined(_HAS_EXCEPTIONS) && _HAS_EXCEPTIONS == 0 // !_LIBCPP_ABI_VCRUNTIME
+
+// When _HAS_EXCEPTIONS == 0, these complete definitions are needed,
+// since they would normally be provided in vcruntime_exception.h
+class bad_alloc : public exception {
+public:
+ bad_alloc() noexcept : exception("bad allocation") {}
+
+private:
+ friend class bad_array_new_length;
+
+ bad_alloc(char const* const __message) noexcept : exception(__message) {}
+};
+
+class bad_array_new_length : public bad_alloc {
+public:
+ bad_array_new_length() noexcept : bad_alloc("bad array new length") {}
+};
+#endif // defined(_LIBCPP_ABI_VCRUNTIME) && defined(_HAS_EXCEPTIONS) && _HAS_EXCEPTIONS == 0
+
+_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void __throw_bad_alloc(); // not in C++ spec
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_bad_array_new_length() {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw bad_array_new_length();
+#else
+ _LIBCPP_VERBOSE_ABORT("bad_array_new_length was thrown in -fno-exceptions mode");
+#endif
+}
+
+#if !defined(_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION) && !defined(_LIBCPP_ABI_VCRUNTIME)
+# ifndef _LIBCPP_CXX03_LANG
+enum class align_val_t : size_t {};
+# else
+enum align_val_t { __zero = 0, __max = (size_t)-1 };
+# endif
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+// Enable the declaration even if the compiler doesn't support the language
+// feature.
+struct destroying_delete_t {
+ explicit destroying_delete_t() = default;
+};
+inline constexpr destroying_delete_t destroying_delete{};
+#endif // _LIBCPP_STD_VER >= 20
+
+} // namespace std
+
+#if defined(_LIBCPP_CXX03_LANG)
+# define _THROW_BAD_ALLOC throw(std::bad_alloc)
+#else
+# define _THROW_BAD_ALLOC
+#endif
+
+#if !defined(_LIBCPP_ABI_VCRUNTIME)
+
+_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz) _THROW_BAD_ALLOC;
+_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, const std::nothrow_t&) _NOEXCEPT
+ _LIBCPP_NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, const std::nothrow_t&) _NOEXCEPT;
+# ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::size_t __sz) _NOEXCEPT;
+# endif
+
+_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz) _THROW_BAD_ALLOC;
+_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz, const std::nothrow_t&) _NOEXCEPT
+ _LIBCPP_NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, const std::nothrow_t&) _NOEXCEPT;
+# ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::size_t __sz) _NOEXCEPT;
+# endif
+
+# ifndef _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
+_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
+_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void*
+operator new(std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _LIBCPP_NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
+# ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
+# endif
+
+_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void*
+operator new[](std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
+_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void*
+operator new[](std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _LIBCPP_NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
+# ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
+_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
+# endif
+# endif
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI void* operator new(std::size_t, void* __p) _NOEXCEPT { return __p; }
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI void* operator new[](std::size_t, void* __p) _NOEXCEPT { return __p; }
+inline _LIBCPP_HIDE_FROM_ABI void operator delete(void*, void*) _NOEXCEPT {}
+inline _LIBCPP_HIDE_FROM_ABI void operator delete[](void*, void*) _NOEXCEPT {}
+
+#endif // !_LIBCPP_ABI_VCRUNTIME
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_CONSTEXPR inline _LIBCPP_HIDE_FROM_ABI bool __is_overaligned_for_new(size_t __align) _NOEXCEPT {
+#ifdef __STDCPP_DEFAULT_NEW_ALIGNMENT__
+ return __align > __STDCPP_DEFAULT_NEW_ALIGNMENT__;
+#else
+ return __align > _LIBCPP_ALIGNOF(max_align_t);
+#endif
+}
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void* __libcpp_operator_new(_Args... __args) {
+#if __has_builtin(__builtin_operator_new) && __has_builtin(__builtin_operator_delete)
+ return __builtin_operator_new(__args...);
+#else
+ return ::operator new(__args...);
+#endif
+}
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void __libcpp_operator_delete(_Args... __args) {
+#if __has_builtin(__builtin_operator_new) && __has_builtin(__builtin_operator_delete)
+ __builtin_operator_delete(__args...);
+#else
+ ::operator delete(__args...);
+#endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void* __libcpp_allocate(size_t __size, size_t __align) {
+#ifndef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
+ if (__is_overaligned_for_new(__align)) {
+ const align_val_t __align_val = static_cast<align_val_t>(__align);
+ return __libcpp_operator_new(__size, __align_val);
+ }
+#endif
+
+ (void)__align;
+ return __libcpp_operator_new(__size);
+}
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void __do_deallocate_handle_size(void* __ptr, size_t __size, _Args... __args) {
+#ifdef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
+ (void)__size;
+ return std::__libcpp_operator_delete(__ptr, __args...);
+#else
+ return std::__libcpp_operator_delete(__ptr, __size, __args...);
+#endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void __libcpp_deallocate(void* __ptr, size_t __size, size_t __align) {
+#if defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
+ (void)__align;
+ return __do_deallocate_handle_size(__ptr, __size);
+#else
+ if (__is_overaligned_for_new(__align)) {
+ const align_val_t __align_val = static_cast<align_val_t>(__align);
+ return __do_deallocate_handle_size(__ptr, __size, __align_val);
+ } else {
+ return __do_deallocate_handle_size(__ptr, __size);
+ }
+#endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI void __libcpp_deallocate_unsized(void* __ptr, size_t __align) {
+#if defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
+ (void)__align;
+ return __libcpp_operator_delete(__ptr);
+#else
+ if (__is_overaligned_for_new(__align)) {
+ const align_val_t __align_val = static_cast<align_val_t>(__align);
+ return __libcpp_operator_delete(__ptr, __align_val);
+ } else {
+ return __libcpp_operator_delete(__ptr);
+ }
+#endif
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp* __launder(_Tp* __p) _NOEXCEPT {
+ static_assert(!(is_function<_Tp>::value), "can't launder functions");
+ static_assert(!(is_same<void, __remove_cv_t<_Tp> >::value), "can't launder cv-void");
+ return __builtin_launder(__p);
+}
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+[[nodiscard]] inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp* launder(_Tp* __p) noexcept {
+ return std::__launder(__p);
+}
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+# if defined(__GCC_DESTRUCTIVE_SIZE) && defined(__GCC_CONSTRUCTIVE_SIZE)
+
+inline constexpr size_t hardware_destructive_interference_size = __GCC_DESTRUCTIVE_SIZE;
+inline constexpr size_t hardware_constructive_interference_size = __GCC_CONSTRUCTIVE_SIZE;
+
+# endif // defined(__GCC_DESTRUCTIVE_SIZE) && defined(__GCC_CONSTRUCTIVE_SIZE)
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdlib>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_NEW
diff --git a/libcxx/include/__cxx03/numbers b/libcxx/include/__cxx03/numbers
new file mode 100644
index 00000000000000..f48ba4baf38ffd
--- /dev/null
+++ b/libcxx/include/__cxx03/numbers
@@ -0,0 +1,164 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_NUMBERS
+#define _LIBCPP_NUMBERS
+
+/*
+ numbers synopsis
+
+namespace std::numbers {
+ template<class T> inline constexpr T e_v = unspecified;
+ template<class T> inline constexpr T log2e_v = unspecified;
+ template<class T> inline constexpr T log10e_v = unspecified;
+ template<class T> inline constexpr T pi_v = unspecified;
+ template<class T> inline constexpr T inv_pi_v = unspecified;
+ template<class T> inline constexpr T inv_sqrtpi_v = unspecified;
+ template<class T> inline constexpr T ln2_v = unspecified;
+ template<class T> inline constexpr T ln10_v = unspecified;
+ template<class T> inline constexpr T sqrt2_v = unspecified;
+ template<class T> inline constexpr T sqrt3_v = unspecified;
+ template<class T> inline constexpr T inv_sqrt3_v = unspecified;
+ template<class T> inline constexpr T egamma_v = unspecified;
+ template<class T> inline constexpr T phi_v = unspecified;
+
+ template<floating_point T> inline constexpr T e_v<T> = see below;
+ template<floating_point T> inline constexpr T log2e_v<T> = see below;
+ template<floating_point T> inline constexpr T log10e_v<T> = see below;
+ template<floating_point T> inline constexpr T pi_v<T> = see below;
+ template<floating_point T> inline constexpr T inv_pi_v<T> = see below;
+ template<floating_point T> inline constexpr T inv_sqrtpi_v<T> = see below;
+ template<floating_point T> inline constexpr T ln2_v<T> = see below;
+ template<floating_point T> inline constexpr T ln10_v<T> = see below;
+ template<floating_point T> inline constexpr T sqrt2_v<T> = see below;
+ template<floating_point T> inline constexpr T sqrt3_v<T> = see below;
+ template<floating_point T> inline constexpr T inv_sqrt3_v<T> = see below;
+ template<floating_point T> inline constexpr T egamma_v<T> = see below;
+ template<floating_point T> inline constexpr T phi_v<T> = see below;
+
+ inline constexpr double e = e_v<double>;
+ inline constexpr double log2e = log2e_v<double>;
+ inline constexpr double log10e = log10e_v<double>;
+ inline constexpr double pi = pi_v<double>;
+ inline constexpr double inv_pi = inv_pi_v<double>;
+ inline constexpr double inv_sqrtpi = inv_sqrtpi_v<double>;
+ inline constexpr double ln2 = ln2_v<double>;
+ inline constexpr double ln10 = ln10_v<double>;
+ inline constexpr double sqrt2 = sqrt2_v<double>;
+ inline constexpr double sqrt3 = sqrt3_v<double>;
+ inline constexpr double inv_sqrt3 = inv_sqrt3_v<double>;
+ inline constexpr double egamma = egamma_v<double>;
+ inline constexpr double phi = phi_v<double>;
+}
+*/
+
+#include <__concepts/arithmetic.h>
+#include <__config>
+#include <version>
+
+#if _LIBCPP_STD_VER >= 20
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace numbers {
+
+template <class _Tp>
+inline constexpr bool __false = false;
+
+template <class _Tp>
+struct __illformed {
+ static_assert(
+ __false<_Tp>,
+ "A program that instantiates a primary template of a mathematical constant variable template is ill-formed.");
+};
+
+template <class _Tp>
+inline constexpr _Tp e_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp log2e_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp log10e_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp pi_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp inv_pi_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp inv_sqrtpi_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp ln2_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp ln10_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp sqrt2_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp sqrt3_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp inv_sqrt3_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp egamma_v = __illformed<_Tp>{};
+template <class _Tp>
+inline constexpr _Tp phi_v = __illformed<_Tp>{};
+
+template <floating_point _Tp>
+inline constexpr _Tp e_v<_Tp> = 2.718281828459045235360287471352662;
+template <floating_point _Tp>
+inline constexpr _Tp log2e_v<_Tp> = 1.442695040888963407359924681001892;
+template <floating_point _Tp>
+inline constexpr _Tp log10e_v<_Tp> = 0.434294481903251827651128918916605;
+template <floating_point _Tp>
+inline constexpr _Tp pi_v<_Tp> = 3.141592653589793238462643383279502;
+template <floating_point _Tp>
+inline constexpr _Tp inv_pi_v<_Tp> = 0.318309886183790671537767526745028;
+template <floating_point _Tp>
+inline constexpr _Tp inv_sqrtpi_v<_Tp> = 0.564189583547756286948079451560772;
+template <floating_point _Tp>
+inline constexpr _Tp ln2_v<_Tp> = 0.693147180559945309417232121458176;
+template <floating_point _Tp>
+inline constexpr _Tp ln10_v<_Tp> = 2.302585092994045684017991454684364;
+template <floating_point _Tp>
+inline constexpr _Tp sqrt2_v<_Tp> = 1.414213562373095048801688724209698;
+template <floating_point _Tp>
+inline constexpr _Tp sqrt3_v<_Tp> = 1.732050807568877293527446341505872;
+template <floating_point _Tp>
+inline constexpr _Tp inv_sqrt3_v<_Tp> = 0.577350269189625764509148780501957;
+template <floating_point _Tp>
+inline constexpr _Tp egamma_v<_Tp> = 0.577215664901532860606512090082402;
+template <floating_point _Tp>
+inline constexpr _Tp phi_v<_Tp> = 1.618033988749894848204586834365638;
+
+inline constexpr double e = e_v<double>;
+inline constexpr double log2e = log2e_v<double>;
+inline constexpr double log10e = log10e_v<double>;
+inline constexpr double pi = pi_v<double>;
+inline constexpr double inv_pi = inv_pi_v<double>;
+inline constexpr double inv_sqrtpi = inv_sqrtpi_v<double>;
+inline constexpr double ln2 = ln2_v<double>;
+inline constexpr double ln10 = ln10_v<double>;
+inline constexpr double sqrt2 = sqrt2_v<double>;
+inline constexpr double sqrt3 = sqrt3_v<double>;
+inline constexpr double inv_sqrt3 = inv_sqrt3_v<double>;
+inline constexpr double egamma = egamma_v<double>;
+inline constexpr double phi = phi_v<double>;
+
+} // namespace numbers
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_NUMBERS
diff --git a/libcxx/include/__cxx03/numeric b/libcxx/include/__cxx03/numeric
new file mode 100644
index 00000000000000..6b92ce3a071237
--- /dev/null
+++ b/libcxx/include/__cxx03/numeric
@@ -0,0 +1,207 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_NUMERIC
+#define _LIBCPP_NUMERIC
+
+/*
+ numeric synopsis
+
+namespace std
+{
+
+template <class InputIterator, class T>
+ constexpr T // constexpr since C++20
+ accumulate(InputIterator first, InputIterator last, T init);
+
+template <class InputIterator, class T, class BinaryOperation>
+ constexpr T // constexpr since C++20
+ accumulate(InputIterator first, InputIterator last, T init, BinaryOperation binary_op);
+
+template<class InputIterator>
+ constexpr typename iterator_traits<InputIterator>::value_type // constexpr since C++20
+ reduce(InputIterator first, InputIterator last); // C++17
+
+template<class InputIterator, class T>
+ constexpr T // constexpr since C++20
+ reduce(InputIterator first, InputIterator last, T init); // C++17
+
+template<class InputIterator, class T, class BinaryOperation>
+ constexpr T // constexpr since C++20
+ reduce(InputIterator first, InputIterator last, T init, BinaryOperation binary_op); // C++17
+
+template <class InputIterator1, class InputIterator2, class T>
+ constexpr T // constexpr since C++20
+ inner_product(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, T init);
+
+template <class InputIterator1, class InputIterator2, class T, class BinaryOperation1, class BinaryOperation2>
+ constexpr T // constexpr since C++20
+ inner_product(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2,
+ T init, BinaryOperation1 binary_op1, BinaryOperation2 binary_op2);
+
+
+template<class InputIterator1, class InputIterator2, class T>
+ constexpr T // constexpr since C++20
+ transform_reduce(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, T init); // C++17
+
+template<class InputIterator1, class InputIterator2, class T, class BinaryOperation1, class BinaryOperation2>
+ constexpr T // constexpr since C++20
+ transform_reduce(InputIterator1 first1, InputIterator1 last1,
+ InputIterator2 first2, T init,
+ BinaryOperation1 binary_op1, BinaryOperation2 binary_op2); // C++17
+
+template<class InputIterator, class T, class BinaryOperation, class UnaryOperation>
+ constexpr T // constexpr since C++20
+ transform_reduce(InputIterator first, InputIterator last, T init,
+ BinaryOperation binary_op, UnaryOperation unary_op); // C++17
+
+template <class InputIterator, class OutputIterator>
+ constexpr OutputIterator // constexpr since C++20
+ partial_sum(InputIterator first, InputIterator last, OutputIterator result);
+
+template <class InputIterator, class OutputIterator, class BinaryOperation>
+ constexpr OutputIterator // constexpr since C++20
+ partial_sum(InputIterator first, InputIterator last, OutputIterator result, BinaryOperation binary_op);
+
+template<class InputIterator, class OutputIterator, class T>
+ constexpr OutputIterator // constexpr since C++20
+ exclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result, T init); // C++17
+
+template<class InputIterator, class OutputIterator, class T, class BinaryOperation>
+ constexpr OutputIterator // constexpr since C++20
+ exclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result, T init, BinaryOperation binary_op); // C++17
+
+template<class InputIterator, class OutputIterator>
+ constexpr OutputIterator // constexpr since C++20
+ inclusive_scan(InputIterator first, InputIterator last, OutputIterator result); // C++17
+
+template<class InputIterator, class OutputIterator, class BinaryOperation>
+ constexpr OutputIterator // constexpr since C++20
+ inclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result, BinaryOperation binary_op); // C++17
+
+template<class InputIterator, class OutputIterator, class BinaryOperation, class T>
+ constexpr OutputIterator // constexpr since C++20
+ inclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result, BinaryOperation binary_op, T init); // C++17
+
+template<class InputIterator, class OutputIterator, class T,
+ class BinaryOperation, class UnaryOperation>
+ constexpr OutputIterator // constexpr since C++20
+ transform_exclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result, T init,
+ BinaryOperation binary_op, UnaryOperation unary_op); // C++17
+
+template<class InputIterator, class OutputIterator,
+ class BinaryOperation, class UnaryOperation>
+ constexpr OutputIterator // constexpr since C++20
+ transform_inclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result,
+ BinaryOperation binary_op, UnaryOperation unary_op); // C++17
+
+template<class InputIterator, class OutputIterator,
+ class BinaryOperation, class UnaryOperation, class T>
+ constexpr OutputIterator // constexpr since C++20
+ transform_inclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result,
+ BinaryOperation binary_op, UnaryOperation unary_op,
+ T init); // C++17
+
+template <class InputIterator, class OutputIterator>
+ constexpr OutputIterator // constexpr since C++20
+ adjacent_difference(InputIterator first, InputIterator last, OutputIterator result);
+
+template <class InputIterator, class OutputIterator, class BinaryOperation>
+ constexpr OutputIterator // constexpr since C++20
+ adjacent_difference(InputIterator first, InputIterator last, OutputIterator result, BinaryOperation binary_op);
+
+template <class ForwardIterator, class T>
+ constexpr void // constexpr since C++20
+ iota(ForwardIterator first, ForwardIterator last, T value);
+
+template <class M, class N>
+ constexpr common_type_t<M,N> gcd(M m, N n); // C++17
+
+template <class M, class N>
+ constexpr common_type_t<M,N> lcm(M m, N n); // C++17
+
+template<class T>
+ constexpr T midpoint(T a, T b) noexcept; // C++20
+
+template<class T>
+ constexpr T* midpoint(T* a, T* b); // C++20
+
+// [numeric.sat], saturation arithmetic
+template<class T>
+constexpr T add_sat(T x, T y) noexcept; // freestanding, Since C++26
+template<class T>
+constexpr T sub_sat(T x, T y) noexcept; // freestanding, Since C++26
+template<class T>
+constexpr T mul_sat(T x, T y) noexcept; // freestanding, Since C++26
+template<class T>
+constexpr T div_sat(T x, T y) noexcept; // freestanding, Since C++26
+template<class T, class U>
+constexpr T saturate_cast(U x) noexcept; // freestanding, Since C++26
+
+} // std
+
+*/
+
+#include <__config>
+
+#include <__numeric/accumulate.h>
+#include <__numeric/adjacent_difference.h>
+#include <__numeric/inner_product.h>
+#include <__numeric/iota.h>
+#include <__numeric/partial_sum.h>
+
+#if _LIBCPP_STD_VER >= 17
+# include <__numeric/exclusive_scan.h>
+# include <__numeric/gcd_lcm.h>
+# include <__numeric/inclusive_scan.h>
+# include <__numeric/pstl.h>
+# include <__numeric/reduce.h>
+# include <__numeric/transform_exclusive_scan.h>
+# include <__numeric/transform_inclusive_scan.h>
+# include <__numeric/transform_reduce.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+# include <__numeric/midpoint.h>
+# include <__numeric/saturation_arithmetic.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 14
+# include <initializer_list>
+# include <limits>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <climits>
+# include <cmath>
+# include <concepts>
+# include <cstdint>
+# include <execution>
+# include <functional>
+# include <iterator>
+# include <new>
+# include <optional>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_NUMERIC
diff --git a/libcxx/include/__cxx03/optional b/libcxx/include/__cxx03/optional
new file mode 100644
index 00000000000000..41d7515a2b6892
--- /dev/null
+++ b/libcxx/include/__cxx03/optional
@@ -0,0 +1,1304 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_OPTIONAL
+#define _LIBCPP_OPTIONAL
+
+/*
+ optional synopsis
+
+// C++1z
+
+namespace std {
+ // [optional.optional], class template optional
+ template <class T>
+ class optional;
+
+ template<class T>
+ concept is-derived-from-optional = requires(const T& t) { // exposition only
+ []<class U>(const optional<U>&){ }(t);
+ };
+
+ // [optional.nullopt], no-value state indicator
+ struct nullopt_t{see below };
+ inline constexpr nullopt_t nullopt(unspecified );
+
+ // [optional.bad.access], class bad_optional_access
+ class bad_optional_access;
+
+ // [optional.relops], relational operators
+ template <class T, class U>
+ constexpr bool operator==(const optional<T>&, const optional<U>&);
+ template <class T, class U>
+ constexpr bool operator!=(const optional<T>&, const optional<U>&);
+ template <class T, class U>
+ constexpr bool operator<(const optional<T>&, const optional<U>&);
+ template <class T, class U>
+ constexpr bool operator>(const optional<T>&, const optional<U>&);
+ template <class T, class U>
+ constexpr bool operator<=(const optional<T>&, const optional<U>&);
+ template <class T, class U>
+ constexpr bool operator>=(const optional<T>&, const optional<U>&);
+ template<class T, three_way_comparable_with<T> U>
+ constexpr compare_three_way_result_t<T, U>
+ operator<=>(const optional<T>&, const optional<U>&); // since C++20
+
+ // [optional.nullops], comparison with nullopt
+ template<class T> constexpr bool operator==(const optional<T>&, nullopt_t) noexcept;
+ template<class T> constexpr bool operator==(nullopt_t, const optional<T>&) noexcept; // until C++17
+ template<class T> constexpr bool operator!=(const optional<T>&, nullopt_t) noexcept; // until C++17
+ template<class T> constexpr bool operator!=(nullopt_t, const optional<T>&) noexcept; // until C++17
+ template<class T> constexpr bool operator<(const optional<T>&, nullopt_t) noexcept; // until C++17
+ template<class T> constexpr bool operator<(nullopt_t, const optional<T>&) noexcept; // until C++17
+ template<class T> constexpr bool operator<=(const optional<T>&, nullopt_t) noexcept; // until C++17
+ template<class T> constexpr bool operator<=(nullopt_t, const optional<T>&) noexcept; // until C++17
+ template<class T> constexpr bool operator>(const optional<T>&, nullopt_t) noexcept; // until C++17
+ template<class T> constexpr bool operator>(nullopt_t, const optional<T>&) noexcept; // until C++17
+ template<class T> constexpr bool operator>=(const optional<T>&, nullopt_t) noexcept; // until C++17
+ template<class T> constexpr bool operator>=(nullopt_t, const optional<T>&) noexcept; // until C++17
+ template<class T>
+ constexpr strong_ordering operator<=>(const optional<T>&, nullopt_t) noexcept; // since C++20
+
+ // [optional.comp.with.t], comparison with T
+ template<class T, class U> constexpr bool operator==(const optional<T>&, const U&);
+ template<class T, class U> constexpr bool operator==(const T&, const optional<U>&);
+ template<class T, class U> constexpr bool operator!=(const optional<T>&, const U&);
+ template<class T, class U> constexpr bool operator!=(const T&, const optional<U>&);
+ template<class T, class U> constexpr bool operator<(const optional<T>&, const U&);
+ template<class T, class U> constexpr bool operator<(const T&, const optional<U>&);
+ template<class T, class U> constexpr bool operator<=(const optional<T>&, const U&);
+ template<class T, class U> constexpr bool operator<=(const T&, const optional<U>&);
+ template<class T, class U> constexpr bool operator>(const optional<T>&, const U&);
+ template<class T, class U> constexpr bool operator>(const T&, const optional<U>&);
+ template<class T, class U> constexpr bool operator>=(const optional<T>&, const U&);
+ template<class T, class U> constexpr bool operator>=(const T&, const optional<U>&);
+ template<class T, class U>
+ requires (!is-derived-from-optional<U>) && three_way_comparable_with<T, U>
+ constexpr compare_three_way_result_t<T, U>
+ operator<=>(const optional<T>&, const U&); // since C++20
+
+ // [optional.specalg], specialized algorithms
+ template<class T>
+ void swap(optional<T>&, optional<T>&) noexcept(see below ); // constexpr in C++20
+
+ template<class T>
+ constexpr optional<see below > make_optional(T&&);
+ template<class T, class... Args>
+ constexpr optional<T> make_optional(Args&&... args);
+ template<class T, class U, class... Args>
+ constexpr optional<T> make_optional(initializer_list<U> il, Args&&... args);
+
+ // [optional.hash], hash support
+ template<class T> struct hash;
+ template<class T> struct hash<optional<T>>;
+
+ template<class T>
+ class optional {
+ public:
+ using value_type = T;
+
+ // [optional.ctor], constructors
+ constexpr optional() noexcept;
+ constexpr optional(nullopt_t) noexcept;
+ constexpr optional(const optional &);
+ constexpr optional(optional &&) noexcept(see below);
+ template<class... Args>
+ constexpr explicit optional(in_place_t, Args &&...);
+ template<class U, class... Args>
+ constexpr explicit optional(in_place_t, initializer_list<U>, Args &&...);
+ template<class U = T>
+ constexpr explicit(see-below) optional(U &&);
+ template<class U>
+ explicit(see-below) optional(const optional<U> &); // constexpr in C++20
+ template<class U>
+ explicit(see-below) optional(optional<U> &&); // constexpr in C++20
+
+ // [optional.dtor], destructor
+ ~optional(); // constexpr in C++20
+
+ // [optional.assign], assignment
+ optional &operator=(nullopt_t) noexcept; // constexpr in C++20
+ constexpr optional &operator=(const optional &);
+ constexpr optional &operator=(optional &&) noexcept(see below);
+ template<class U = T> optional &operator=(U &&); // constexpr in C++20
+ template<class U> optional &operator=(const optional<U> &); // constexpr in C++20
+ template<class U> optional &operator=(optional<U> &&); // constexpr in C++20
+ template<class... Args> T& emplace(Args &&...); // constexpr in C++20
+ template<class U, class... Args> T& emplace(initializer_list<U>, Args &&...); // constexpr in C++20
+
+ // [optional.swap], swap
+ void swap(optional &) noexcept(see below ); // constexpr in C++20
+
+ // [optional.observe], observers
+ constexpr T const *operator->() const noexcept;
+ constexpr T *operator->() noexcept;
+ constexpr T const &operator*() const & noexcept;
+ constexpr T &operator*() & noexcept;
+ constexpr T &&operator*() && noexcept;
+ constexpr const T &&operator*() const && noexcept;
+ constexpr explicit operator bool() const noexcept;
+ constexpr bool has_value() const noexcept;
+ constexpr T const &value() const &;
+ constexpr T &value() &;
+ constexpr T &&value() &&;
+ constexpr const T &&value() const &&;
+ template<class U> constexpr T value_or(U &&) const &;
+ template<class U> constexpr T value_or(U &&) &&;
+
+ // [optional.monadic], monadic operations
+ template<class F> constexpr auto and_then(F&& f) &; // since C++23
+ template<class F> constexpr auto and_then(F&& f) &&; // since C++23
+ template<class F> constexpr auto and_then(F&& f) const&; // since C++23
+ template<class F> constexpr auto and_then(F&& f) const&&; // since C++23
+ template<class F> constexpr auto transform(F&& f) &; // since C++23
+ template<class F> constexpr auto transform(F&& f) &&; // since C++23
+ template<class F> constexpr auto transform(F&& f) const&; // since C++23
+ template<class F> constexpr auto transform(F&& f) const&&; // since C++23
+ template<class F> constexpr optional or_else(F&& f) &&; // since C++23
+ template<class F> constexpr optional or_else(F&& f) const&; // since C++23
+
+ // [optional.mod], modifiers
+ void reset() noexcept; // constexpr in C++20
+
+ private:
+ T *val; // exposition only
+ };
+
+ template<class T>
+ optional(T) -> optional<T>;
+
+} // namespace std
+
+*/
+
+#include <__assert>
+#include <__compare/compare_three_way_result.h>
+#include <__compare/three_way_comparable.h>
+#include <__concepts/invocable.h>
+#include <__config>
+#include <__exception/exception.h>
+#include <__functional/hash.h>
+#include <__functional/invoke.h>
+#include <__functional/unary_function.h>
+#include <__fwd/functional.h>
+#include <__memory/addressof.h>
+#include <__memory/construct_at.h>
+#include <__tuple/sfinae_helpers.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/disjunction.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_destructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_scalar.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/is_trivially_assignable.h>
+#include <__type_traits/is_trivially_constructible.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/negation.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <__verbose_abort>
+#include <initializer_list>
+#include <new>
+#include <version>
+
+// standard-mandated includes
+
+// [optional.syn]
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+namespace std // purposefully not using versioning namespace
+{
+
+class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS bad_optional_access : public exception {
+public:
+ _LIBCPP_HIDE_FROM_ABI bad_optional_access() _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_optional_access(const bad_optional_access&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_optional_access& operator=(const bad_optional_access&) _NOEXCEPT = default;
+ // Get the key function ~bad_optional_access() into the dylib
+ ~bad_optional_access() _NOEXCEPT override;
+ const char* what() const _NOEXCEPT override;
+};
+
+} // namespace std
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS void
+__throw_bad_optional_access() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw bad_optional_access();
+# else
+ _LIBCPP_VERBOSE_ABORT("bad_optional_access was thrown in -fno-exceptions mode");
+# endif
+}
+
+struct nullopt_t {
+ struct __secret_tag {
+ explicit __secret_tag() = default;
+ };
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit nullopt_t(__secret_tag, __secret_tag) noexcept {}
+};
+
+inline constexpr nullopt_t nullopt{nullopt_t::__secret_tag{}, nullopt_t::__secret_tag{}};
+
+struct __optional_construct_from_invoke_tag {};
+
+template <class _Tp, bool = is_trivially_destructible<_Tp>::value>
+struct __optional_destruct_base;
+
+template <class _Tp>
+struct __optional_destruct_base<_Tp, false> {
+ typedef _Tp value_type;
+ static_assert(is_object_v<value_type>, "instantiation of optional with a non-object type is undefined behavior");
+ union {
+ char __null_state_;
+ value_type __val_;
+ };
+ bool __engaged_;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__optional_destruct_base() {
+ if (__engaged_)
+ __val_.~value_type();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __optional_destruct_base() noexcept : __null_state_(), __engaged_(false) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __optional_destruct_base(in_place_t, _Args&&... __args)
+ : __val_(std::forward<_Args>(__args)...), __engaged_(true) {}
+
+# if _LIBCPP_STD_VER >= 23
+ template <class _Fp, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __optional_destruct_base(
+ __optional_construct_from_invoke_tag, _Fp&& __f, _Args&&... __args)
+ : __val_(std::invoke(std::forward<_Fp>(__f), std::forward<_Args>(__args)...)), __engaged_(true) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void reset() noexcept {
+ if (__engaged_) {
+ __val_.~value_type();
+ __engaged_ = false;
+ }
+ }
+};
+
+template <class _Tp>
+struct __optional_destruct_base<_Tp, true> {
+ typedef _Tp value_type;
+ static_assert(is_object_v<value_type>, "instantiation of optional with a non-object type is undefined behavior");
+ union {
+ char __null_state_;
+ value_type __val_;
+ };
+ bool __engaged_;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __optional_destruct_base() noexcept : __null_state_(), __engaged_(false) {}
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __optional_destruct_base(in_place_t, _Args&&... __args)
+ : __val_(std::forward<_Args>(__args)...), __engaged_(true) {}
+
+# if _LIBCPP_STD_VER >= 23
+ template <class _Fp, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI constexpr __optional_destruct_base(
+ __optional_construct_from_invoke_tag, _Fp&& __f, _Args&&... __args)
+ : __val_(std::invoke(std::forward<_Fp>(__f), std::forward<_Args>(__args)...)), __engaged_(true) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void reset() noexcept {
+ if (__engaged_) {
+ __engaged_ = false;
+ }
+ }
+};
+
+template <class _Tp, bool = is_reference<_Tp>::value>
+struct __optional_storage_base : __optional_destruct_base<_Tp> {
+ using __base = __optional_destruct_base<_Tp>;
+ using value_type = _Tp;
+ using __base::__base;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool has_value() const noexcept { return this->__engaged_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type& __get() & noexcept { return this->__val_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr const value_type& __get() const& noexcept { return this->__val_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type&& __get() && noexcept { return std::move(this->__val_); }
+ _LIBCPP_HIDE_FROM_ABI constexpr const value_type&& __get() const&& noexcept { return std::move(this->__val_); }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __construct(_Args&&... __args) {
+ _LIBCPP_ASSERT_INTERNAL(!has_value(), "__construct called for engaged __optional_storage");
+ std::__construct_at(std::addressof(this->__val_), std::forward<_Args>(__args)...);
+ this->__engaged_ = true;
+ }
+
+ template <class _That>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __construct_from(_That&& __opt) {
+ if (__opt.has_value())
+ __construct(std::forward<_That>(__opt).__get());
+ }
+
+ template <class _That>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __assign_from(_That&& __opt) {
+ if (this->__engaged_ == __opt.has_value()) {
+ if (this->__engaged_)
+ this->__val_ = std::forward<_That>(__opt).__get();
+ } else {
+ if (this->__engaged_)
+ this->reset();
+ else
+ __construct(std::forward<_That>(__opt).__get());
+ }
+ }
+};
+
+// optional<T&> is currently required to be ill-formed. However, it may
+// be allowed in the future. For this reason, it has already been implemented
+// to ensure we can make the change in an ABI-compatible manner.
+template <class _Tp>
+struct __optional_storage_base<_Tp, true> {
+ using value_type = _Tp;
+ using __raw_type = remove_reference_t<_Tp>;
+ __raw_type* __value_;
+
+ template <class _Up>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __can_bind_reference() {
+ using _RawUp = __libcpp_remove_reference_t<_Up>;
+ using _UpPtr = _RawUp*;
+ using _RawTp = __libcpp_remove_reference_t<_Tp>;
+ using _TpPtr = _RawTp*;
+ using _CheckLValueArg =
+ integral_constant<bool,
+ (is_lvalue_reference<_Up>::value && is_convertible<_UpPtr, _TpPtr>::value) ||
+ is_same<_RawUp, reference_wrapper<_RawTp>>::value ||
+ is_same<_RawUp, reference_wrapper<__remove_const_t<_RawTp>>>::value >;
+ return (is_lvalue_reference<_Tp>::value && _CheckLValueArg::value) ||
+ (is_rvalue_reference<_Tp>::value && !is_lvalue_reference<_Up>::value &&
+ is_convertible<_UpPtr, _TpPtr>::value);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __optional_storage_base() noexcept : __value_(nullptr) {}
+
+ template <class _UArg>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __optional_storage_base(in_place_t, _UArg&& __uarg)
+ : __value_(std::addressof(__uarg)) {
+ static_assert(__can_bind_reference<_UArg>(),
+ "Attempted to construct a reference element in tuple from a "
+ "possible temporary");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void reset() noexcept { __value_ = nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool has_value() const noexcept { return __value_ != nullptr; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type& __get() const& noexcept { return *__value_; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type&& __get() const&& noexcept { return std::forward<value_type>(*__value_); }
+
+ template <class _UArg>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __construct(_UArg&& __val) {
+ _LIBCPP_ASSERT_INTERNAL(!has_value(), "__construct called for engaged __optional_storage");
+ static_assert(__can_bind_reference<_UArg>(),
+ "Attempted to construct a reference element in tuple from a "
+ "possible temporary");
+ __value_ = std::addressof(__val);
+ }
+
+ template <class _That>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __construct_from(_That&& __opt) {
+ if (__opt.has_value())
+ __construct(std::forward<_That>(__opt).__get());
+ }
+
+ template <class _That>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __assign_from(_That&& __opt) {
+ if (has_value() == __opt.has_value()) {
+ if (has_value())
+ *__value_ = std::forward<_That>(__opt).__get();
+ } else {
+ if (has_value())
+ reset();
+ else
+ __construct(std::forward<_That>(__opt).__get());
+ }
+ }
+};
+
+template <class _Tp, bool = is_trivially_copy_constructible<_Tp>::value>
+struct __optional_copy_base : __optional_storage_base<_Tp> {
+ using __optional_storage_base<_Tp>::__optional_storage_base;
+};
+
+template <class _Tp>
+struct __optional_copy_base<_Tp, false> : __optional_storage_base<_Tp> {
+ using __optional_storage_base<_Tp>::__optional_storage_base;
+
+ _LIBCPP_HIDE_FROM_ABI __optional_copy_base() = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __optional_copy_base(const __optional_copy_base& __opt) {
+ this->__construct_from(__opt);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __optional_copy_base(__optional_copy_base&&) = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_copy_base& operator=(const __optional_copy_base&) = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_copy_base& operator=(__optional_copy_base&&) = default;
+};
+
+template <class _Tp, bool = is_trivially_move_constructible<_Tp>::value>
+struct __optional_move_base : __optional_copy_base<_Tp> {
+ using __optional_copy_base<_Tp>::__optional_copy_base;
+};
+
+template <class _Tp>
+struct __optional_move_base<_Tp, false> : __optional_copy_base<_Tp> {
+ using value_type = _Tp;
+ using __optional_copy_base<_Tp>::__optional_copy_base;
+
+ _LIBCPP_HIDE_FROM_ABI __optional_move_base() = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_move_base(const __optional_move_base&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ __optional_move_base(__optional_move_base&& __opt) noexcept(is_nothrow_move_constructible_v<value_type>) {
+ this->__construct_from(std::move(__opt));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __optional_move_base& operator=(const __optional_move_base&) = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_move_base& operator=(__optional_move_base&&) = default;
+};
+
+template <class _Tp,
+ bool = is_trivially_destructible<_Tp>::value && is_trivially_copy_constructible<_Tp>::value &&
+ is_trivially_copy_assignable<_Tp>::value>
+struct __optional_copy_assign_base : __optional_move_base<_Tp> {
+ using __optional_move_base<_Tp>::__optional_move_base;
+};
+
+template <class _Tp>
+struct __optional_copy_assign_base<_Tp, false> : __optional_move_base<_Tp> {
+ using __optional_move_base<_Tp>::__optional_move_base;
+
+ _LIBCPP_HIDE_FROM_ABI __optional_copy_assign_base() = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_copy_assign_base(const __optional_copy_assign_base&) = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_copy_assign_base(__optional_copy_assign_base&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __optional_copy_assign_base&
+ operator=(const __optional_copy_assign_base& __opt) {
+ this->__assign_from(__opt);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __optional_copy_assign_base& operator=(__optional_copy_assign_base&&) = default;
+};
+
+template <class _Tp,
+ bool = is_trivially_destructible<_Tp>::value && is_trivially_move_constructible<_Tp>::value &&
+ is_trivially_move_assignable<_Tp>::value>
+struct __optional_move_assign_base : __optional_copy_assign_base<_Tp> {
+ using __optional_copy_assign_base<_Tp>::__optional_copy_assign_base;
+};
+
+template <class _Tp>
+struct __optional_move_assign_base<_Tp, false> : __optional_copy_assign_base<_Tp> {
+ using value_type = _Tp;
+ using __optional_copy_assign_base<_Tp>::__optional_copy_assign_base;
+
+ _LIBCPP_HIDE_FROM_ABI __optional_move_assign_base() = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_move_assign_base(const __optional_move_assign_base& __opt) = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_move_assign_base(__optional_move_assign_base&&) = default;
+ _LIBCPP_HIDE_FROM_ABI __optional_move_assign_base& operator=(const __optional_move_assign_base&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __optional_move_assign_base&
+ operator=(__optional_move_assign_base&& __opt) noexcept(
+ is_nothrow_move_assignable_v<value_type> && is_nothrow_move_constructible_v<value_type>) {
+ this->__assign_from(std::move(__opt));
+ return *this;
+ }
+};
+
+template <class _Tp>
+using __optional_sfinae_ctor_base_t =
+ __sfinae_ctor_base< is_copy_constructible<_Tp>::value, is_move_constructible<_Tp>::value >;
+
+template <class _Tp>
+using __optional_sfinae_assign_base_t =
+ __sfinae_assign_base< (is_copy_constructible<_Tp>::value && is_copy_assignable<_Tp>::value),
+ (is_move_constructible<_Tp>::value && is_move_assignable<_Tp>::value) >;
+
+template <class _Tp>
+class optional;
+
+# if _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+concept __is_derived_from_optional = requires(const _Tp& __t) { []<class _Up>(const optional<_Up>&) {}(__t); };
+
+# endif // _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+struct __is_std_optional : false_type {};
+template <class _Tp>
+struct __is_std_optional<optional<_Tp>> : true_type {};
+
+template <class _Tp>
+class _LIBCPP_DECLSPEC_EMPTY_BASES optional
+ : private __optional_move_assign_base<_Tp>,
+ private __optional_sfinae_ctor_base_t<_Tp>,
+ private __optional_sfinae_assign_base_t<_Tp> {
+ using __base = __optional_move_assign_base<_Tp>;
+
+public:
+ using value_type = _Tp;
+
+ using __trivially_relocatable = conditional_t<__libcpp_is_trivially_relocatable<_Tp>::value, optional, void>;
+
+private:
+ // Disable the reference extension using this static assert.
+ static_assert(!is_same_v<__remove_cvref_t<value_type>, in_place_t>,
+ "instantiation of optional with in_place_t is ill-formed");
+ static_assert(!is_same_v<__remove_cvref_t<value_type>, nullopt_t>,
+ "instantiation of optional with nullopt_t is ill-formed");
+ static_assert(!is_reference_v<value_type>, "instantiation of optional with a reference type is ill-formed");
+ static_assert(is_destructible_v<value_type>, "instantiation of optional with a non-destructible type is ill-formed");
+ static_assert(!is_array_v<value_type>, "instantiation of optional with an array type is ill-formed");
+
+ // LWG2756: conditionally explicit conversion from _Up
+ struct _CheckOptionalArgsConstructor {
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __enable_implicit() {
+ return is_constructible_v<_Tp, _Up&&> && is_convertible_v<_Up&&, _Tp>;
+ }
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __enable_explicit() {
+ return is_constructible_v<_Tp, _Up&&> && !is_convertible_v<_Up&&, _Tp>;
+ }
+ };
+ template <class _Up>
+ using _CheckOptionalArgsCtor =
+ _If< _IsNotSame<__remove_cvref_t<_Up>, in_place_t>::value && _IsNotSame<__remove_cvref_t<_Up>, optional>::value &&
+ (!is_same_v<remove_cv_t<_Tp>, bool> || !__is_std_optional<__remove_cvref_t<_Up>>::value),
+ _CheckOptionalArgsConstructor,
+ __check_tuple_constructor_fail >;
+ template <class _QualUp>
+ struct _CheckOptionalLikeConstructor {
+ template <class _Up, class _Opt = optional<_Up>>
+ using __check_constructible_from_opt =
+ _Or< is_constructible<_Tp, _Opt&>,
+ is_constructible<_Tp, _Opt const&>,
+ is_constructible<_Tp, _Opt&&>,
+ is_constructible<_Tp, _Opt const&&>,
+ is_convertible<_Opt&, _Tp>,
+ is_convertible<_Opt const&, _Tp>,
+ is_convertible<_Opt&&, _Tp>,
+ is_convertible<_Opt const&&, _Tp> >;
+ template <class _Up, class _Opt = optional<_Up>>
+ using __check_assignable_from_opt =
+ _Or< is_assignable<_Tp&, _Opt&>,
+ is_assignable<_Tp&, _Opt const&>,
+ is_assignable<_Tp&, _Opt&&>,
+ is_assignable<_Tp&, _Opt const&&> >;
+ template <class _Up, class _QUp = _QualUp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __enable_implicit() {
+ return is_convertible<_QUp, _Tp>::value &&
+ (is_same_v<remove_cv_t<_Tp>, bool> || !__check_constructible_from_opt<_Up>::value);
+ }
+ template <class _Up, class _QUp = _QualUp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __enable_explicit() {
+ return !is_convertible<_QUp, _Tp>::value &&
+ (is_same_v<remove_cv_t<_Tp>, bool> || !__check_constructible_from_opt<_Up>::value);
+ }
+ template <class _Up, class _QUp = _QualUp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __enable_assign() {
+ // Construction and assignability of _QUp to _Tp has already been
+ // checked.
+ return !__check_constructible_from_opt<_Up>::value && !__check_assignable_from_opt<_Up>::value;
+ }
+ };
+
+ template <class _Up, class _QualUp>
+ using _CheckOptionalLikeCtor =
+ _If< _And< _IsNotSame<_Up, _Tp>, is_constructible<_Tp, _QualUp> >::value,
+ _CheckOptionalLikeConstructor<_QualUp>,
+ __check_tuple_constructor_fail >;
+ template <class _Up, class _QualUp>
+ using _CheckOptionalLikeAssign =
+ _If< _And< _IsNotSame<_Up, _Tp>, is_constructible<_Tp, _QualUp>, is_assignable<_Tp&, _QualUp> >::value,
+ _CheckOptionalLikeConstructor<_QualUp>,
+ __check_tuple_constructor_fail >;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr optional() noexcept {}
+ _LIBCPP_HIDE_FROM_ABI constexpr optional(const optional&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr optional(optional&&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr optional(nullopt_t) noexcept {}
+
+ template <
+ class _InPlaceT,
+ class... _Args,
+ class = enable_if_t< _And< _IsSame<_InPlaceT, in_place_t>, is_constructible<value_type, _Args...> >::value > >
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit optional(_InPlaceT, _Args&&... __args)
+ : __base(in_place, std::forward<_Args>(__args)...) {}
+
+ template <class _Up,
+ class... _Args,
+ class = enable_if_t< is_constructible_v<value_type, initializer_list<_Up>&, _Args...>> >
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit optional(in_place_t, initializer_list<_Up> __il, _Args&&... __args)
+ : __base(in_place, __il, std::forward<_Args>(__args)...) {}
+
+ template <class _Up = value_type,
+ enable_if_t< _CheckOptionalArgsCtor<_Up>::template __enable_implicit<_Up>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr optional(_Up&& __v) : __base(in_place, std::forward<_Up>(__v)) {}
+
+ template <class _Up, enable_if_t< _CheckOptionalArgsCtor<_Up>::template __enable_explicit<_Up>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit optional(_Up&& __v) : __base(in_place, std::forward<_Up>(__v)) {}
+
+ // LWG2756: conditionally explicit conversion from const optional<_Up>&
+ template <class _Up,
+ enable_if_t< _CheckOptionalLikeCtor<_Up, _Up const&>::template __enable_implicit<_Up>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 optional(const optional<_Up>& __v) {
+ this->__construct_from(__v);
+ }
+ template <class _Up,
+ enable_if_t< _CheckOptionalLikeCtor<_Up, _Up const&>::template __enable_explicit<_Up>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit optional(const optional<_Up>& __v) {
+ this->__construct_from(__v);
+ }
+
+ // LWG2756: conditionally explicit conversion from optional<_Up>&&
+ template <class _Up, enable_if_t< _CheckOptionalLikeCtor<_Up, _Up&&>::template __enable_implicit<_Up>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 optional(optional<_Up>&& __v) {
+ this->__construct_from(std::move(__v));
+ }
+ template <class _Up, enable_if_t< _CheckOptionalLikeCtor<_Up, _Up&&>::template __enable_explicit<_Up>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit optional(optional<_Up>&& __v) {
+ this->__construct_from(std::move(__v));
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ template <class _Tag,
+ class _Fp,
+ class... _Args,
+ __enable_if_t<_IsSame<_Tag, __optional_construct_from_invoke_tag>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit optional(_Tag, _Fp&& __f, _Args&&... __args)
+ : __base(__optional_construct_from_invoke_tag{}, std::forward<_Fp>(__f), std::forward<_Args>(__args)...) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 optional& operator=(nullopt_t) noexcept {
+ reset();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr optional& operator=(const optional&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr optional& operator=(optional&&) = default;
+
+ // LWG2756
+ template <
+ class _Up = value_type,
+ class = enable_if_t< _And< _IsNotSame<__remove_cvref_t<_Up>, optional>,
+ _Or< _IsNotSame<__remove_cvref_t<_Up>, value_type>, _Not<is_scalar<value_type>> >,
+ is_constructible<value_type, _Up>,
+ is_assignable<value_type&, _Up> >::value> >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 optional& operator=(_Up&& __v) {
+ if (this->has_value())
+ this->__get() = std::forward<_Up>(__v);
+ else
+ this->__construct(std::forward<_Up>(__v));
+ return *this;
+ }
+
+ // LWG2756
+ template <class _Up,
+ enable_if_t< _CheckOptionalLikeAssign<_Up, _Up const&>::template __enable_assign<_Up>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 optional& operator=(const optional<_Up>& __v) {
+ this->__assign_from(__v);
+ return *this;
+ }
+
+ // LWG2756
+ template <class _Up, enable_if_t< _CheckOptionalLikeCtor<_Up, _Up&&>::template __enable_assign<_Up>(), int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 optional& operator=(optional<_Up>&& __v) {
+ this->__assign_from(std::move(__v));
+ return *this;
+ }
+
+ template <class... _Args, class = enable_if_t< is_constructible_v<value_type, _Args...> > >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& emplace(_Args&&... __args) {
+ reset();
+ this->__construct(std::forward<_Args>(__args)...);
+ return this->__get();
+ }
+
+ template <class _Up,
+ class... _Args,
+ class = enable_if_t< is_constructible_v<value_type, initializer_list<_Up>&, _Args...> > >
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& emplace(initializer_list<_Up> __il, _Args&&... __args) {
+ reset();
+ this->__construct(__il, std::forward<_Args>(__args)...);
+ return this->__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ swap(optional& __opt) noexcept(is_nothrow_move_constructible_v<value_type> && is_nothrow_swappable_v<value_type>) {
+ if (this->has_value() == __opt.has_value()) {
+ using std::swap;
+ if (this->has_value())
+ swap(this->__get(), __opt.__get());
+ } else {
+ if (this->has_value()) {
+ __opt.__construct(std::move(this->__get()));
+ reset();
+ } else {
+ this->__construct(std::move(__opt.__get()));
+ __opt.reset();
+ }
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr add_pointer_t<value_type const> operator->() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(this->has_value(), "optional operator-> called on a disengaged value");
+ return std::addressof(this->__get());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr add_pointer_t<value_type> operator->() noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(this->has_value(), "optional operator-> called on a disengaged value");
+ return std::addressof(this->__get());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const value_type& operator*() const& noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(this->has_value(), "optional operator* called on a disengaged value");
+ return this->__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type& operator*() & noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(this->has_value(), "optional operator* called on a disengaged value");
+ return this->__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type&& operator*() && noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(this->has_value(), "optional operator* called on a disengaged value");
+ return std::move(this->__get());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const value_type&& operator*() const&& noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(this->has_value(), "optional operator* called on a disengaged value");
+ return std::move(this->__get());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return has_value(); }
+
+ using __base::__get;
+ using __base::has_value;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr value_type const& value() const& {
+ if (!this->has_value())
+ __throw_bad_optional_access();
+ return this->__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr value_type& value() & {
+ if (!this->has_value())
+ __throw_bad_optional_access();
+ return this->__get();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr value_type&& value() && {
+ if (!this->has_value())
+ __throw_bad_optional_access();
+ return std::move(this->__get());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr value_type const&& value() const&& {
+ if (!this->has_value())
+ __throw_bad_optional_access();
+ return std::move(this->__get());
+ }
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type value_or(_Up&& __v) const& {
+ static_assert(is_copy_constructible_v<value_type>, "optional<T>::value_or: T must be copy constructible");
+ static_assert(is_convertible_v<_Up, value_type>, "optional<T>::value_or: U must be convertible to T");
+ return this->has_value() ? this->__get() : static_cast<value_type>(std::forward<_Up>(__v));
+ }
+
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI constexpr value_type value_or(_Up&& __v) && {
+ static_assert(is_move_constructible_v<value_type>, "optional<T>::value_or: T must be move constructible");
+ static_assert(is_convertible_v<_Up, value_type>, "optional<T>::value_or: U must be convertible to T");
+ return this->has_value() ? std::move(this->__get()) : static_cast<value_type>(std::forward<_Up>(__v));
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr auto and_then(_Func&& __f) & {
+ using _Up = invoke_result_t<_Func, value_type&>;
+ static_assert(__is_std_optional<remove_cvref_t<_Up>>::value,
+ "Result of f(value()) must be a specialization of std::optional");
+ if (*this)
+ return std::invoke(std::forward<_Func>(__f), value());
+ return remove_cvref_t<_Up>();
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr auto and_then(_Func&& __f) const& {
+ using _Up = invoke_result_t<_Func, const value_type&>;
+ static_assert(__is_std_optional<remove_cvref_t<_Up>>::value,
+ "Result of f(value()) must be a specialization of std::optional");
+ if (*this)
+ return std::invoke(std::forward<_Func>(__f), value());
+ return remove_cvref_t<_Up>();
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr auto and_then(_Func&& __f) && {
+ using _Up = invoke_result_t<_Func, value_type&&>;
+ static_assert(__is_std_optional<remove_cvref_t<_Up>>::value,
+ "Result of f(std::move(value())) must be a specialization of std::optional");
+ if (*this)
+ return std::invoke(std::forward<_Func>(__f), std::move(value()));
+ return remove_cvref_t<_Up>();
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto and_then(_Func&& __f) const&& {
+ using _Up = invoke_result_t<_Func, const value_type&&>;
+ static_assert(__is_std_optional<remove_cvref_t<_Up>>::value,
+ "Result of f(std::move(value())) must be a specialization of std::optional");
+ if (*this)
+ return std::invoke(std::forward<_Func>(__f), std::move(value()));
+ return remove_cvref_t<_Up>();
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr auto transform(_Func&& __f) & {
+ using _Up = remove_cv_t<invoke_result_t<_Func, value_type&>>;
+ static_assert(!is_array_v<_Up>, "Result of f(value()) should not be an Array");
+ static_assert(!is_same_v<_Up, in_place_t>, "Result of f(value()) should not be std::in_place_t");
+ static_assert(!is_same_v<_Up, nullopt_t>, "Result of f(value()) should not be std::nullopt_t");
+ static_assert(is_object_v<_Up>, "Result of f(value()) should be an object type");
+ if (*this)
+ return optional<_Up>(__optional_construct_from_invoke_tag{}, std::forward<_Func>(__f), value());
+ return optional<_Up>();
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr auto transform(_Func&& __f) const& {
+ using _Up = remove_cv_t<invoke_result_t<_Func, const value_type&>>;
+ static_assert(!is_array_v<_Up>, "Result of f(value()) should not be an Array");
+ static_assert(!is_same_v<_Up, in_place_t>, "Result of f(value()) should not be std::in_place_t");
+ static_assert(!is_same_v<_Up, nullopt_t>, "Result of f(value()) should not be std::nullopt_t");
+ static_assert(is_object_v<_Up>, "Result of f(value()) should be an object type");
+ if (*this)
+ return optional<_Up>(__optional_construct_from_invoke_tag{}, std::forward<_Func>(__f), value());
+ return optional<_Up>();
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr auto transform(_Func&& __f) && {
+ using _Up = remove_cv_t<invoke_result_t<_Func, value_type&&>>;
+ static_assert(!is_array_v<_Up>, "Result of f(std::move(value())) should not be an Array");
+ static_assert(!is_same_v<_Up, in_place_t>, "Result of f(std::move(value())) should not be std::in_place_t");
+ static_assert(!is_same_v<_Up, nullopt_t>, "Result of f(std::move(value())) should not be std::nullopt_t");
+ static_assert(is_object_v<_Up>, "Result of f(std::move(value())) should be an object type");
+ if (*this)
+ return optional<_Up>(__optional_construct_from_invoke_tag{}, std::forward<_Func>(__f), std::move(value()));
+ return optional<_Up>();
+ }
+
+ template <class _Func>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS constexpr auto transform(_Func&& __f) const&& {
+ using _Up = remove_cvref_t<invoke_result_t<_Func, const value_type&&>>;
+ static_assert(!is_array_v<_Up>, "Result of f(std::move(value())) should not be an Array");
+ static_assert(!is_same_v<_Up, in_place_t>, "Result of f(std::move(value())) should not be std::in_place_t");
+ static_assert(!is_same_v<_Up, nullopt_t>, "Result of f(std::move(value())) should not be std::nullopt_t");
+ static_assert(is_object_v<_Up>, "Result of f(std::move(value())) should be an object type");
+ if (*this)
+ return optional<_Up>(__optional_construct_from_invoke_tag{}, std::forward<_Func>(__f), std::move(value()));
+ return optional<_Up>();
+ }
+
+ template <invocable _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr optional or_else(_Func&& __f) const&
+ requires is_copy_constructible_v<value_type>
+ {
+ static_assert(is_same_v<remove_cvref_t<invoke_result_t<_Func>>, optional>,
+ "Result of f() should be the same type as this optional");
+ if (*this)
+ return *this;
+ return std::forward<_Func>(__f)();
+ }
+
+ template <invocable _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr optional or_else(_Func&& __f) &&
+ requires is_move_constructible_v<value_type>
+ {
+ static_assert(is_same_v<remove_cvref_t<invoke_result_t<_Func>>, optional>,
+ "Result of f() should be the same type as this optional");
+ if (*this)
+ return std::move(*this);
+ return std::forward<_Func>(__f)();
+ }
+# endif // _LIBCPP_STD_VER >= 23
+
+ using __base::reset;
+};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _Tp>
+optional(_Tp) -> optional<_Tp>;
+# endif
+
+// Comparisons between optionals
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() == std::declval<const _Up&>()), bool>,
+ bool >
+operator==(const optional<_Tp>& __x, const optional<_Up>& __y) {
+ if (static_cast<bool>(__x) != static_cast<bool>(__y))
+ return false;
+ if (!static_cast<bool>(__x))
+ return true;
+ return *__x == *__y;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() != std::declval<const _Up&>()), bool>,
+ bool >
+operator!=(const optional<_Tp>& __x, const optional<_Up>& __y) {
+ if (static_cast<bool>(__x) != static_cast<bool>(__y))
+ return true;
+ if (!static_cast<bool>(__x))
+ return false;
+ return *__x != *__y;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() < std::declval<const _Up&>()), bool>,
+ bool >
+operator<(const optional<_Tp>& __x, const optional<_Up>& __y) {
+ if (!static_cast<bool>(__y))
+ return false;
+ if (!static_cast<bool>(__x))
+ return true;
+ return *__x < *__y;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() > std::declval<const _Up&>()), bool>,
+ bool >
+operator>(const optional<_Tp>& __x, const optional<_Up>& __y) {
+ if (!static_cast<bool>(__x))
+ return false;
+ if (!static_cast<bool>(__y))
+ return true;
+ return *__x > *__y;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() <= std::declval<const _Up&>()), bool>,
+ bool >
+operator<=(const optional<_Tp>& __x, const optional<_Up>& __y) {
+ if (!static_cast<bool>(__x))
+ return true;
+ if (!static_cast<bool>(__y))
+ return false;
+ return *__x <= *__y;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() >= std::declval<const _Up&>()), bool>,
+ bool >
+operator>=(const optional<_Tp>& __x, const optional<_Up>& __y) {
+ if (!static_cast<bool>(__y))
+ return true;
+ if (!static_cast<bool>(__x))
+ return false;
+ return *__x >= *__y;
+}
+
+# if _LIBCPP_STD_VER >= 20
+
+template <class _Tp, three_way_comparable_with<_Tp> _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr compare_three_way_result_t<_Tp, _Up>
+operator<=>(const optional<_Tp>& __x, const optional<_Up>& __y) {
+ if (__x && __y)
+ return *__x <=> *__y;
+ return __x.has_value() <=> __y.has_value();
+}
+
+# endif // _LIBCPP_STD_VER >= 20
+
+// Comparisons with nullopt
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(const optional<_Tp>& __x, nullopt_t) noexcept {
+ return !static_cast<bool>(__x);
+}
+
+# if _LIBCPP_STD_VER <= 17
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(nullopt_t, const optional<_Tp>& __x) noexcept {
+ return !static_cast<bool>(__x);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(const optional<_Tp>& __x, nullopt_t) noexcept {
+ return static_cast<bool>(__x);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(nullopt_t, const optional<_Tp>& __x) noexcept {
+ return static_cast<bool>(__x);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<(const optional<_Tp>&, nullopt_t) noexcept {
+ return false;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<(nullopt_t, const optional<_Tp>& __x) noexcept {
+ return static_cast<bool>(__x);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(const optional<_Tp>& __x, nullopt_t) noexcept {
+ return !static_cast<bool>(__x);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(nullopt_t, const optional<_Tp>&) noexcept {
+ return true;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>(const optional<_Tp>& __x, nullopt_t) noexcept {
+ return static_cast<bool>(__x);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>(nullopt_t, const optional<_Tp>&) noexcept {
+ return false;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(const optional<_Tp>&, nullopt_t) noexcept {
+ return true;
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(nullopt_t, const optional<_Tp>& __x) noexcept {
+ return !static_cast<bool>(__x);
+}
+
+# else // _LIBCPP_STD_VER <= 17
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr strong_ordering operator<=>(const optional<_Tp>& __x, nullopt_t) noexcept {
+ return __x.has_value() <=> false;
+}
+
+# endif // _LIBCPP_STD_VER <= 17
+
+// Comparisons with T
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() == std::declval<const _Up&>()), bool>,
+ bool >
+operator==(const optional<_Tp>& __x, const _Up& __v) {
+ return static_cast<bool>(__x) ? *__x == __v : false;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() == std::declval<const _Up&>()), bool>,
+ bool >
+operator==(const _Tp& __v, const optional<_Up>& __x) {
+ return static_cast<bool>(__x) ? __v == *__x : false;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() != std::declval<const _Up&>()), bool>,
+ bool >
+operator!=(const optional<_Tp>& __x, const _Up& __v) {
+ return static_cast<bool>(__x) ? *__x != __v : true;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() != std::declval<const _Up&>()), bool>,
+ bool >
+operator!=(const _Tp& __v, const optional<_Up>& __x) {
+ return static_cast<bool>(__x) ? __v != *__x : true;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() < std::declval<const _Up&>()), bool>,
+ bool >
+operator<(const optional<_Tp>& __x, const _Up& __v) {
+ return static_cast<bool>(__x) ? *__x < __v : true;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() < std::declval<const _Up&>()), bool>,
+ bool >
+operator<(const _Tp& __v, const optional<_Up>& __x) {
+ return static_cast<bool>(__x) ? __v < *__x : false;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() <= std::declval<const _Up&>()), bool>,
+ bool >
+operator<=(const optional<_Tp>& __x, const _Up& __v) {
+ return static_cast<bool>(__x) ? *__x <= __v : true;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() <= std::declval<const _Up&>()), bool>,
+ bool >
+operator<=(const _Tp& __v, const optional<_Up>& __x) {
+ return static_cast<bool>(__x) ? __v <= *__x : false;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() > std::declval<const _Up&>()), bool>,
+ bool >
+operator>(const optional<_Tp>& __x, const _Up& __v) {
+ return static_cast<bool>(__x) ? *__x > __v : false;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() > std::declval<const _Up&>()), bool>,
+ bool >
+operator>(const _Tp& __v, const optional<_Up>& __x) {
+ return static_cast<bool>(__x) ? __v > *__x : true;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() >= std::declval<const _Up&>()), bool>,
+ bool >
+operator>=(const optional<_Tp>& __x, const _Up& __v) {
+ return static_cast<bool>(__x) ? *__x >= __v : false;
+}
+
+template <class _Tp, class _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<
+ is_convertible_v<decltype(std::declval<const _Tp&>() >= std::declval<const _Up&>()), bool>,
+ bool >
+operator>=(const _Tp& __v, const optional<_Up>& __x) {
+ return static_cast<bool>(__x) ? __v >= *__x : true;
+}
+
+# if _LIBCPP_STD_VER >= 20
+
+template <class _Tp, class _Up>
+ requires(!__is_derived_from_optional<_Up>) && three_way_comparable_with<_Tp, _Up>
+_LIBCPP_HIDE_FROM_ABI constexpr compare_three_way_result_t<_Tp, _Up>
+operator<=>(const optional<_Tp>& __x, const _Up& __v) {
+ return __x.has_value() ? *__x <=> __v : strong_ordering::less;
+}
+
+# endif // _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI
+_LIBCPP_CONSTEXPR_SINCE_CXX20 enable_if_t< is_move_constructible_v<_Tp> && is_swappable_v<_Tp>, void >
+swap(optional<_Tp>& __x, optional<_Tp>& __y) noexcept(noexcept(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr optional<decay_t<_Tp>> make_optional(_Tp&& __v) {
+ return optional<decay_t<_Tp>>(std::forward<_Tp>(__v));
+}
+
+template <class _Tp, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr optional<_Tp> make_optional(_Args&&... __args) {
+ return optional<_Tp>(in_place, std::forward<_Args>(__args)...);
+}
+
+template <class _Tp, class _Up, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr optional<_Tp> make_optional(initializer_list<_Up> __il, _Args&&... __args) {
+ return optional<_Tp>(in_place, __il, std::forward<_Args>(__args)...);
+}
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS hash< __enable_hash_helper<optional<_Tp>, remove_const_t<_Tp>> > {
+# if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef optional<_Tp> argument_type;
+ _LIBCPP_DEPRECATED_IN_CXX17 typedef size_t result_type;
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const optional<_Tp>& __opt) const {
+ return static_cast<bool>(__opt) ? hash<remove_const_t<_Tp>>()(*__opt) : 0;
+ }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <climits>
+# include <concepts>
+# include <ctime>
+# include <iterator>
+# include <limits>
+# include <memory>
+# include <ratio>
+# include <stdexcept>
+# include <tuple>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+# include <variant>
+#endif
+
+#endif // _LIBCPP_OPTIONAL
diff --git a/libcxx/include/__cxx03/ostream b/libcxx/include/__cxx03/ostream
new file mode 100644
index 00000000000000..359d3c0e19c4cf
--- /dev/null
+++ b/libcxx/include/__cxx03/ostream
@@ -0,0 +1,202 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_OSTREAM
+#define _LIBCPP_OSTREAM
+
+/*
+ ostream synopsis
+
+template <class charT, class traits = char_traits<charT> >
+class basic_ostream
+ : virtual public basic_ios<charT,traits>
+{
+public:
+ // types (inherited from basic_ios (27.5.4)):
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ // 27.7.2.2 Constructor/destructor:
+ explicit basic_ostream(basic_streambuf<char_type,traits>* sb);
+ basic_ostream(basic_ostream&& rhs);
+ virtual ~basic_ostream();
+
+ // 27.7.2.3 Assign/swap
+ basic_ostream& operator=(const basic_ostream& rhs) = delete; // C++14
+ basic_ostream& operator=(basic_ostream&& rhs);
+ void swap(basic_ostream& rhs);
+
+ // 27.7.2.4 Prefix/suffix:
+ class sentry;
+
+ // 27.7.2.6 Formatted output:
+ basic_ostream& operator<<(basic_ostream& (*pf)(basic_ostream&));
+ basic_ostream& operator<<(basic_ios<charT, traits>& (*pf)(basic_ios<charT,traits>&));
+ basic_ostream& operator<<(ios_base& (*pf)(ios_base&));
+ basic_ostream& operator<<(bool n);
+ basic_ostream& operator<<(short n);
+ basic_ostream& operator<<(unsigned short n);
+ basic_ostream& operator<<(int n);
+ basic_ostream& operator<<(unsigned int n);
+ basic_ostream& operator<<(long n);
+ basic_ostream& operator<<(unsigned long n);
+ basic_ostream& operator<<(long long n);
+ basic_ostream& operator<<(unsigned long long n);
+ basic_ostream& operator<<(float f);
+ basic_ostream& operator<<(double f);
+ basic_ostream& operator<<(long double f);
+ basic_ostream& operator<<(const void* p);
+ basic_ostream& operator<<(const volatile void* val); // C++23
+ basic_ostream& operator<<(basic_streambuf<char_type,traits>* sb);
+ basic_ostream& operator<<(nullptr_t);
+
+ // 27.7.2.7 Unformatted output:
+ basic_ostream& put(char_type c);
+ basic_ostream& write(const char_type* s, streamsize n);
+ basic_ostream& flush();
+
+ // 27.7.2.5 seeks:
+ pos_type tellp();
+ basic_ostream& seekp(pos_type);
+ basic_ostream& seekp(off_type, ios_base::seekdir);
+protected:
+ basic_ostream(const basic_ostream& rhs) = delete;
+ basic_ostream(basic_ostream&& rhs);
+ // 27.7.3.3 Assign/swap
+ basic_ostream& operator=(basic_ostream& rhs) = delete;
+ basic_ostream& operator=(const basic_ostream&& rhs);
+ void swap(basic_ostream& rhs);
+};
+
+// 27.7.2.6.4 character inserters
+
+template<class charT, class traits>
+ basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>&, charT);
+
+template<class charT, class traits>
+ basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>&, char);
+
+template<class traits>
+ basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, char);
+
+// signed and unsigned
+
+template<class traits>
+ basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, signed char);
+
+template<class traits>
+ basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, unsigned char);
+
+// NTBS
+template<class charT, class traits>
+ basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>&, const charT*);
+
+template<class charT, class traits>
+ basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>&, const char*);
+
+template<class traits>
+ basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, const char*);
+
+// signed and unsigned
+template<class traits>
+basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, const signed char*);
+
+template<class traits>
+ basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, const unsigned char*);
+
+// swap:
+template <class charT, class traits>
+ void swap(basic_ostream<charT, traits>& x, basic_ostream<charT, traits>& y);
+
+template <class charT, class traits>
+ basic_ostream<charT,traits>& endl(basic_ostream<charT,traits>& os);
+
+template <class charT, class traits>
+ basic_ostream<charT,traits>& ends(basic_ostream<charT,traits>& os);
+
+template <class charT, class traits>
+ basic_ostream<charT,traits>& flush(basic_ostream<charT,traits>& os);
+
+// rvalue stream insertion
+template <class Stream, class T>
+ Stream&& operator<<(Stream&& os, const T& x);
+
+template<class traits>
+basic_ostream<char, traits>& operator<<(basic_ostream<char, traits>&, wchar_t) = delete; // since C++20
+template<class traits>
+basic_ostream<char, traits>& operator<<(basic_ostream<char, traits>&, char8_t) = delete; // since C++20
+template<class traits>
+basic_ostream<char, traits>& operator<<(basic_ostream<char, traits>&, char16_t) = delete; // since C++20
+template<class traits>
+basic_ostream<char, traits>& operator<<(basic_ostream<char, traits>&, char32_t) = delete; // since C++20
+template<class traits>
+basic_ostream<wchar_t, traits>& operator<<(basic_ostream<wchar_t, traits>&, char8_t) = delete; // since C++20
+template<class traits>
+basic_ostream<wchar_t, traits>& operator<<(basic_ostream<wchar_t, traits>&, char16_t) = delete; // since C++20
+template<class traits>
+basic_ostream<wchar_t, traits>& operator<<(basic_ostream<wchar_t, traits>&, char32_t) = delete; // since C++20
+template<class traits>
+basic_ostream<char, traits>& operator<<(basic_ostream<char, traits>&, const wchar_t*) = delete; // since C++20
+template<class traits>
+basic_ostream<char, traits>& operator<<(basic_ostream<char, traits>&, const char8_t*) = delete; // since C++20
+template<class traits>
+basic_ostream<char, traits>& operator<<(basic_ostream<char, traits>&, const char16_t*) = delete; // since C++20
+template<class traits>
+basic_ostream<char, traits>& operator<<(basic_ostream<char, traits>&, const char32_t*) = delete; // since C++20
+template<class traits>
+basic_ostream<wchar_t, traits>& operator<<(basic_ostream<wchar_t, traits>&, const char8_t*) = delete; // since C++20
+template<class traits>
+basic_ostream<wchar_t, traits>& operator<<(basic_ostream<wchar_t, traits>&, const char16_t*) = delete; // since C++20
+template<class traits>
+basic_ostream<wchar_t, traits>& operator<<(basic_ostream<wchar_t, traits>&, const char32_t*) = delete; // since C++20
+
+// [ostream.formatted.print], print functions
+template<class... Args> // since C++23
+ void print(ostream& os, format_string<Args...> fmt, Args&&... args);
+template<class... Args> // since C++23
+ void println(ostream& os, format_string<Args...> fmt, Args&&... args);
+void println(ostream& os); // since C++26
+
+void vprint_unicode(ostream& os, string_view fmt, format_args args); // since C++23
+void vprint_nonunicode(ostream& os, string_view fmt, format_args args); // since C++23
+} // std
+
+*/
+
+#include <__config>
+
+#include <__ostream/basic_ostream.h>
+
+#if _LIBCPP_STD_VER >= 23
+# include <__ostream/print.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstdio>
+# include <cstdlib>
+# include <format>
+# include <iosfwd>
+# include <iterator>
+# include <print>
+# include <stdexcept>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_OSTREAM
diff --git a/libcxx/include/__cxx03/print b/libcxx/include/__cxx03/print
new file mode 100644
index 00000000000000..1a579daff270f7
--- /dev/null
+++ b/libcxx/include/__cxx03/print
@@ -0,0 +1,402 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_PRINT
+#define _LIBCPP_PRINT
+
+/*
+namespace std {
+ // [print.fun], print functions
+ template<class... Args>
+ void print(format_string<Args...> fmt, Args&&... args);
+ void println(); // Since C++26
+ template<class... Args>
+ void print(FILE* stream, format_string<Args...> fmt, Args&&... args);
+ void println(FILE* stream); // Since C++26
+
+ template<class... Args>
+ void println(format_string<Args...> fmt, Args&&... args);
+ template<class... Args>
+ void println(FILE* stream, format_string<Args...> fmt, Args&&... args);
+
+ void vprint_unicode(string_view fmt, format_args args);
+ void vprint_unicode(FILE* stream, string_view fmt, format_args args);
+
+ void vprint_nonunicode(string_view fmt, format_args args);
+ void vprint_nonunicode(FILE* stream, string_view fmt, format_args args);
+}
+*/
+
+#include <__assert>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__system_error/system_error.h>
+#include <__utility/forward.h>
+#include <cerrno>
+#include <cstdio>
+#include <format>
+#include <string>
+#include <string_view>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifdef _LIBCPP_WIN32API
+_LIBCPP_EXPORTED_FROM_ABI bool __is_windows_terminal(FILE* __stream);
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+// A wrapper for WriteConsoleW which is used to write to the Windows
+// console. This function is in the dylib to avoid pulling in windows.h
+// in the library headers. The function itself uses some private parts
+// of the dylib too.
+//
+// The function does not depend on the language standard used. Guarding
+// it with C++23 would fail since the dylib is currently built using C++20.
+//
+// Note the function is only implemented on the Windows platform.
+_LIBCPP_EXPORTED_FROM_ABI void __write_to_windows_console(FILE* __stream, wstring_view __view);
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+#elif __has_include(<unistd.h>)
+_LIBCPP_EXPORTED_FROM_ABI bool __is_posix_terminal(FILE* __stream);
+#endif // _LIBCPP_WIN32API
+
+#if _LIBCPP_STD_VER >= 23
+
+# ifndef _LIBCPP_HAS_NO_UNICODE
+// This is the code to transcode UTF-8 to UTF-16. This is used on
+// Windows for the native Unicode API. The code is modeled to make it
+// easier to extend to
+//
+// P2728R0 Unicode in the Library, Part 1: UTF Transcoding
+//
+// This paper is still under heavy development so it makes no sense yet
+// to strictly follow the paper.
+namespace __unicode {
+
+// The names of these concepts are modelled after P2728R0, but the
+// implementation is not. char16_t may contain 32-bits so depending on the
+// number of bits is an issue.
+# ifdef _LIBCPP_SHORT_WCHAR
+template <class _Tp>
+concept __utf16_code_unit =
+ same_as<_Tp, char16_t>
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ || same_as<_Tp, wchar_t>
+# endif
+ ;
+template <class _Tp>
+concept __utf32_code_unit = same_as<_Tp, char32_t>;
+# else // _LIBCPP_SHORT_WCHAR
+template <class _Tp>
+concept __utf16_code_unit = same_as<_Tp, char16_t>;
+template <class _Tp>
+concept __utf32_code_unit =
+ same_as<_Tp, char32_t>
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ || same_as<_Tp, wchar_t>
+# endif
+ ;
+# endif // _LIBCPP_SHORT_WCHAR
+
+// Pass by reference since an output_iterator may not be copyable.
+template <class _OutIt>
+_LIBCPP_HIDE_FROM_ABI constexpr void __encode(_OutIt&, char32_t) = delete;
+
+template <class _OutIt>
+ requires __utf16_code_unit<iter_value_t<_OutIt>>
+_LIBCPP_HIDE_FROM_ABI constexpr void __encode(_OutIt& __out_it, char32_t __value) {
+ // [print.fun]/7 : "if `out` contains invalid code units, the behavior is undefined and implementations are encouraged
+ // to diagnose it".
+ _LIBCPP_ASSERT_UNCATEGORIZED(__is_scalar_value(__value), "an invalid unicode scalar value results in invalid UTF-16");
+
+ if (__value < 0x10000) {
+ *__out_it++ = __value;
+ return;
+ }
+
+ __value -= 0x10000;
+ *__out_it++ = 0xd800 + (__value >> 10);
+ *__out_it++ = 0xdc00 + (__value & 0x3FF);
+}
+
+template <class _OutIt>
+ requires __utf32_code_unit<iter_value_t<_OutIt>>
+_LIBCPP_HIDE_FROM_ABI constexpr void __encode(_OutIt& __out_it, char32_t __value) {
+ // [print.fun]/7 : "if `out` contains invalid code units, the behavior is undefined and implementations are encouraged
+ // to diagnose it".
+ _LIBCPP_ASSERT_UNCATEGORIZED(__is_scalar_value(__value), "an invalid unicode scalar value results in invalid UTF-32");
+ *__out_it++ = __value;
+}
+
+template <class _OutIt, input_iterator _InIt>
+ requires output_iterator<_OutIt, const iter_value_t<_OutIt>&> && (!same_as<iter_value_t<_OutIt>, iter_value_t<_InIt>>)
+_LIBCPP_HIDE_FROM_ABI constexpr _OutIt __transcode(_InIt __first, _InIt __last, _OutIt __out_it) {
+ // The __code_point_view has a basic_string_view interface.
+ // When transcoding becomes part of the standard we probably want to
+ // look at smarter algorithms.
+ // For example, when processing a code point that is encoded in
+ // 1 to 3 code units in UTF-8, the result will always be encoded
+ // in 1 code unit in UTF-16 (code points that require 4 code
+ // units in UTF-8 will require 2 code units in UTF-16).
+ //
+ // Note if P2728 is accepted types like int may become valid. In that case
+ // the __code_point_view should use a span. Libc++ will remove support for
+ // char_traits<int>.
+
+ // TODO PRINT Validate with clang-tidy
+ // NOLINTNEXTLINE(bugprone-dangling-handle)
+ basic_string_view<iter_value_t<_InIt>> __data{__first, __last};
+ __code_point_view<iter_value_t<_InIt>> __view{__data.begin(), __data.end()};
+ while (!__view.__at_end())
+ __unicode::__encode(__out_it, __view.__consume().__code_point);
+ return __out_it;
+}
+
+} // namespace __unicode
+
+# endif // _LIBCPP_HAS_NO_UNICODE
+
+namespace __print {
+
+// [print.fun]/2
+// Effects: If the ordinary literal encoding ([lex.charset]) is UTF-8, equivalent to:
+// vprint_unicode(stream, fmt.str, make_format_args(args...));
+// Otherwise, equivalent to:
+// vprint_nonunicode(stream, fmt.str, make_format_args(args...));
+//
+// Based on the compiler and its compilation flags this value is or is
+// not true. As mentioned in P2093R14 this only affects Windows. The
+// test below could also be done for
+// - GCC using __GNUC_EXECUTION_CHARSET_NAME
+// https://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html
+// - Clang using __clang_literal_encoding__
+// https://clang.llvm.org/docs/LanguageExtensions.html#builtin-macros
+// (note at the time of writing Clang is hard-coded to UTF-8.)
+//
+
+# ifdef _LIBCPP_HAS_NO_UNICODE
+inline constexpr bool __use_unicode_execution_charset = false;
+# elif defined(_MSVC_EXECUTION_CHARACTER_SET)
+// This is the same test MSVC STL uses in their implementation of <print>
+// See: https://learn.microsoft.com/en-us/windows/win32/intl/code-page-identifiers
+inline constexpr bool __use_unicode_execution_charset = _MSVC_EXECUTION_CHARACTER_SET == 65001;
+# else
+inline constexpr bool __use_unicode_execution_charset = true;
+# endif
+
+_LIBCPP_HIDE_FROM_ABI inline bool __is_terminal([[maybe_unused]] FILE* __stream) {
+ // The macro _LIBCPP_TESTING_PRINT_IS_TERMINAL is used to change
+ // the behavior in the test. This is not part of the public API.
+# ifdef _LIBCPP_TESTING_PRINT_IS_TERMINAL
+ return _LIBCPP_TESTING_PRINT_IS_TERMINAL(__stream);
+# elif _LIBCPP_AVAILABILITY_HAS_PRINT == 0
+ return false;
+# elif defined(_LIBCPP_WIN32API)
+ return std::__is_windows_terminal(__stream);
+# elif __has_include(<unistd.h>)
+ return std::__is_posix_terminal(__stream);
+# else
+# error "Provide a way to determine whether a FILE* is a terminal"
+# endif
+}
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void
+__vprint_nonunicode(FILE* __stream, string_view __fmt, format_args __args, bool __write_nl) {
+ _LIBCPP_ASSERT_NON_NULL(__stream, "__stream must be a valid pointer to an output C stream");
+ string __str = std::vformat(__fmt, __args);
+ if (__write_nl)
+ __str.push_back('\n');
+
+ size_t __size = fwrite(__str.data(), 1, __str.size(), __stream);
+ if (__size < __str.size()) {
+ if (std::feof(__stream))
+ std::__throw_system_error(EIO, "EOF while writing the formatted output");
+ std::__throw_system_error(std::ferror(__stream), "failed to write formatted output");
+ }
+}
+
+# ifndef _LIBCPP_HAS_NO_UNICODE
+
+// Note these helper functions are mainly used to aid testing.
+// On POSIX systems and Windows the output is no longer considered a
+// terminal when the output is redirected. Typically during testing the
+// output is redirected to be able to capture it. This makes it hard to
+// test this code path.
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void
+__vprint_unicode_posix(FILE* __stream, string_view __fmt, format_args __args, bool __write_nl, bool __is_terminal) {
+ // TODO PRINT Should flush errors throw too?
+ if (__is_terminal)
+ std::fflush(__stream);
+
+ __print::__vprint_nonunicode(__stream, __fmt, __args, __write_nl);
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void
+__vprint_unicode_windows(FILE* __stream, string_view __fmt, format_args __args, bool __write_nl, bool __is_terminal) {
+ if (!__is_terminal)
+ return __print::__vprint_nonunicode(__stream, __fmt, __args, __write_nl);
+
+ // TODO PRINT Should flush errors throw too?
+ std::fflush(__stream);
+
+ string __str = std::vformat(__fmt, __args);
+ // UTF-16 uses the same number or less code units than UTF-8.
+ // However the size of the code unit is 16 bits instead of 8 bits.
+ //
+ // The buffer uses the worst-case estimate and should never resize.
+ // However when the string is large this could lead to OOM. Using a
+ // smaller size might work, but since the buffer uses a grow factor
+ // the final size might be larger when the estimate is wrong.
+ //
+ // TODO PRINT profile and improve the speed of this code.
+ __format::__retarget_buffer<wchar_t> __buffer{__str.size()};
+ __unicode::__transcode(__str.begin(), __str.end(), __buffer.__make_output_iterator());
+ if (__write_nl)
+ __buffer.push_back(L'\n');
+
+ [[maybe_unused]] wstring_view __view = __buffer.__view();
+
+ // The macro _LIBCPP_TESTING_PRINT_WRITE_TO_WINDOWS_CONSOLE_FUNCTION is used to change
+ // the behavior in the test. This is not part of the public API.
+# ifdef _LIBCPP_TESTING_PRINT_WRITE_TO_WINDOWS_CONSOLE_FUNCTION
+ _LIBCPP_TESTING_PRINT_WRITE_TO_WINDOWS_CONSOLE_FUNCTION(__stream, __view);
+# elif defined(_LIBCPP_WIN32API)
+ std::__write_to_windows_console(__stream, __view);
+# else
+ std::__throw_runtime_error("No defintion of _LIBCPP_TESTING_PRINT_WRITE_TO_WINDOWS_CONSOLE_FUNCTION and "
+ "__write_to_windows_console is not available.");
+# endif
+}
+# endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void
+__vprint_unicode([[maybe_unused]] FILE* __stream,
+ [[maybe_unused]] string_view __fmt,
+ [[maybe_unused]] format_args __args,
+ [[maybe_unused]] bool __write_nl) {
+ _LIBCPP_ASSERT_NON_NULL(__stream, "__stream must be a valid pointer to an output C stream");
+
+ // [print.fun]
+ // 7 - Effects: If stream refers to a terminal capable of displaying
+ // Unicode, writes out to the terminal using the native Unicode
+ // API; if out contains invalid code units, the behavior is
+ // undefined and implementations are encouraged to diagnose it.
+ // Otherwise writes out to stream unchanged. If the native
+ // Unicode API is used, the function flushes stream before
+ // writing out.
+ // 8 - Throws: Any exception thrown by the call to vformat
+ // ([format.err.report]). system_error if writing to the terminal
+ // or stream fails. May throw bad_alloc.
+ // 9 - Recommended practice: If invoking the native Unicode API
+ // requires transcoding, implementations should substitute
+ // invalid code units with U+FFFD replacement character per the
+ // Unicode Standard, Chapter 3.9 U+FFFD Substitution in
+ // Conversion.
+
+ // On non-Windows platforms the Unicode API is the normal file I/O API
+ // so there the call can be forwarded to the non_unicode API. On
+ // Windows there is a different API. This API requires transcoding.
+
+# ifndef _LIBCPP_WIN32API
+ __print::__vprint_unicode_posix(__stream, __fmt, __args, __write_nl, __print::__is_terminal(__stream));
+# elif !defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+ __print::__vprint_unicode_windows(__stream, __fmt, __args, __write_nl, __print::__is_terminal(__stream));
+# else
+# error "Windows builds with wchar_t disabled are not supported."
+# endif
+}
+
+# endif // _LIBCPP_HAS_NO_UNICODE
+
+} // namespace __print
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void print(FILE* __stream, format_string<_Args...> __fmt, _Args&&... __args) {
+# ifndef _LIBCPP_HAS_NO_UNICODE
+ if constexpr (__print::__use_unicode_execution_charset)
+ __print::__vprint_unicode(__stream, __fmt.get(), std::make_format_args(__args...), false);
+ else
+ __print::__vprint_nonunicode(__stream, __fmt.get(), std::make_format_args(__args...), false);
+# else // _LIBCPP_HAS_NO_UNICODE
+ __print::__vprint_nonunicode(__stream, __fmt.get(), std::make_format_args(__args...), false);
+# endif // _LIBCPP_HAS_NO_UNICODE
+}
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void print(format_string<_Args...> __fmt, _Args&&... __args) {
+ std::print(stdout, __fmt, std::forward<_Args>(__args)...);
+}
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void println(FILE* __stream, format_string<_Args...> __fmt, _Args&&... __args) {
+# ifndef _LIBCPP_HAS_NO_UNICODE
+ // Note the wording in the Standard is inefficient. The output of
+ // std::format is a std::string which is then copied. This solution
+ // just appends a newline at the end of the output.
+ if constexpr (__print::__use_unicode_execution_charset)
+ __print::__vprint_unicode(__stream, __fmt.get(), std::make_format_args(__args...), true);
+ else
+ __print::__vprint_nonunicode(__stream, __fmt.get(), std::make_format_args(__args...), true);
+# else // _LIBCPP_HAS_NO_UNICODE
+ __print::__vprint_nonunicode(__stream, __fmt.get(), std::make_format_args(__args...), true);
+# endif // _LIBCPP_HAS_NO_UNICODE
+}
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void println(FILE* __stream) {
+ std::print(__stream, "\n");
+}
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void println() {
+ println(stdout);
+}
+
+template <class... _Args>
+_LIBCPP_HIDE_FROM_ABI void println(format_string<_Args...> __fmt, _Args&&... __args) {
+ std::println(stdout, __fmt, std::forward<_Args>(__args)...);
+}
+
+# ifndef _LIBCPP_HAS_NO_UNICODE
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void vprint_unicode(FILE* __stream, string_view __fmt, format_args __args) {
+ __print::__vprint_unicode(__stream, __fmt, __args, false);
+}
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void vprint_unicode(string_view __fmt, format_args __args) {
+ std::vprint_unicode(stdout, __fmt, __args);
+}
+
+# endif // _LIBCPP_HAS_NO_UNICODE
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void vprint_nonunicode(FILE* __stream, string_view __fmt, format_args __args) {
+ __print::__vprint_nonunicode(__stream, __fmt, __args, false);
+}
+
+template <class = void> // TODO PRINT template or availability markup fires too eagerly (http://llvm.org/PR61563).
+_LIBCPP_HIDE_FROM_ABI inline void vprint_nonunicode(string_view __fmt, format_args __args) {
+ std::vprint_nonunicode(stdout, __fmt, __args);
+}
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_PRINT
diff --git a/libcxx/include/__cxx03/queue b/libcxx/include/__cxx03/queue
new file mode 100644
index 00000000000000..9508de9f9eff22
--- /dev/null
+++ b/libcxx/include/__cxx03/queue
@@ -0,0 +1,956 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_QUEUE
+#define _LIBCPP_QUEUE
+
+/*
+ queue synopsis
+
+namespace std
+{
+
+template <class T, class Container = deque<T>>
+class queue
+{
+public:
+ typedef Container container_type;
+ typedef typename container_type::value_type value_type;
+ typedef typename container_type::reference reference;
+ typedef typename container_type::const_reference const_reference;
+ typedef typename container_type::size_type size_type;
+
+protected:
+ container_type c;
+
+public:
+ queue() = default;
+ ~queue() = default;
+
+ queue(const queue& q) = default;
+ queue(queue&& q) = default;
+
+ queue& operator=(const queue& q) = default;
+ queue& operator=(queue&& q) = default;
+
+ explicit queue(const container_type& c);
+ explicit queue(container_type&& c)
+ template<class InputIterator>
+ queue(InputIterator first, InputIterator last); // since C++23
+ template<container-compatible-range<T> R> queue(from_range_t, R&& rg); // since C++23
+ template <class Alloc>
+ explicit queue(const Alloc& a);
+ template <class Alloc>
+ queue(const container_type& c, const Alloc& a);
+ template <class Alloc>
+ queue(container_type&& c, const Alloc& a);
+ template <class Alloc>
+ queue(const queue& q, const Alloc& a);
+ template <class Alloc>
+ queue(queue&& q, const Alloc& a);
+ template <class InputIterator, class Alloc>
+ queue(InputIterator first, InputIterator last, const Alloc&); // since C++23
+ template<container-compatible-range<T> R, class Alloc>
+ queue(from_range_t, R&& rg, const Alloc&); // since C++23
+
+ bool empty() const;
+ size_type size() const;
+
+ reference front();
+ const_reference front() const;
+ reference back();
+ const_reference back() const;
+
+ void push(const value_type& v);
+ void push(value_type&& v);
+ template<container-compatible-range<T> R>
+ void push_range(R&& rg); // C++23
+ template <class... Args> reference emplace(Args&&... args); // reference in C++17
+ void pop();
+
+ void swap(queue& q) noexcept(is_nothrow_swappable_v<Container>)
+};
+
+template<class Container>
+ queue(Container) -> queue<typename Container::value_type, Container>; // C++17
+
+template<class InputIterator>
+ queue(InputIterator, InputIterator) -> queue<iter-value-type<InputIterator>>; // since C++23
+
+template<ranges::input_range R>
+ queue(from_range_t, R&&) -> queue<ranges::range_value_t<R>>; // since C++23
+
+template<class Container, class Allocator>
+ queue(Container, Allocator) -> queue<typename Container::value_type, Container>; // C++17
+
+template<class InputIterator, class Allocator>
+ queue(InputIterator, InputIterator, Allocator)
+ -> queue<iter-value-type<InputIterator>,
+ deque<iter-value-type<InputIterator>, Allocator>>; // since C++23
+
+template<ranges::input_range R, class Allocator>
+ queue(from_range_t, R&&, Allocator)
+ -> queue<ranges::range_value_t<R>, deque<ranges::range_value_t<R>, Allocator>>; // since C++23
+
+template <class T, class Container>
+ bool operator==(const queue<T, Container>& x,const queue<T, Container>& y);
+
+template <class T, class Container>
+ bool operator< (const queue<T, Container>& x,const queue<T, Container>& y);
+
+template <class T, class Container>
+ bool operator!=(const queue<T, Container>& x,const queue<T, Container>& y);
+
+template <class T, class Container>
+ bool operator> (const queue<T, Container>& x,const queue<T, Container>& y);
+
+template <class T, class Container>
+ bool operator>=(const queue<T, Container>& x,const queue<T, Container>& y);
+
+template <class T, class Container>
+ bool operator<=(const queue<T, Container>& x,const queue<T, Container>& y);
+
+template<class T, three_way_comparable Container>
+ compare_three_way_result_t<Container>
+ operator<=>(const queue<T, Container>& x, const queue<T, Container>& y); // since C++20
+
+template <class T, class Container>
+ void swap(queue<T, Container>& x, queue<T, Container>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class T, class Container = vector<T>,
+ class Compare = less<typename Container::value_type>>
+class priority_queue
+{
+public:
+ typedef Container container_type;
+ typedef typename container_type::value_type value_type;
+ typedef typename container_type::reference reference;
+ typedef typename container_type::const_reference const_reference;
+ typedef typename container_type::size_type size_type;
+
+protected:
+ container_type c;
+ Compare comp;
+
+public:
+ priority_queue() : priority_queue(Compare()) {} // C++20
+ explicit priority_queue(const Compare& x) : priority_queue(x, Container()) {}
+ priority_queue(const Compare& x, const Container&);
+ explicit priority_queue(const Compare& x = Compare(), Container&& = Container()); // before C++20
+ priority_queue(const Compare& x, Container&&); // C++20
+ template <class InputIterator>
+ priority_queue(InputIterator first, InputIterator last,
+ const Compare& comp = Compare());
+ template <class InputIterator>
+ priority_queue(InputIterator first, InputIterator last,
+ const Compare& comp, const Container& c);
+ template <class InputIterator>
+ priority_queue(InputIterator first, InputIterator last,
+ const Compare& comp, Container&& c);
+ template <container-compatible-range<T> R>
+ priority_queue(from_range_t, R&& rg, const Compare& x = Compare()); // since C++23
+ template <class Alloc>
+ explicit priority_queue(const Alloc& a);
+ template <class Alloc>
+ priority_queue(const Compare& comp, const Alloc& a);
+ template <class Alloc>
+ priority_queue(const Compare& comp, const Container& c,
+ const Alloc& a);
+ template <class Alloc>
+ priority_queue(const Compare& comp, Container&& c,
+ const Alloc& a);
+ template <class InputIterator>
+ priority_queue(InputIterator first, InputIterator last,
+ const Alloc& a);
+ template <class InputIterator>
+ priority_queue(InputIterator first, InputIterator last,
+ const Compare& comp, const Alloc& a);
+ template <class InputIterator>
+ priority_queue(InputIterator first, InputIterator last,
+ const Compare& comp, const Container& c, const Alloc& a);
+ template <class InputIterator>
+ priority_queue(InputIterator first, InputIterator last,
+ const Compare& comp, Container&& c, const Alloc& a);
+ template <container-compatible-range<T> R, class Alloc>
+ priority_queue(from_range_t, R&& rg, const Compare&, const Alloc&); // since C++23
+ template <container-compatible-range<T> R, class Alloc>
+ priority_queue(from_range_t, R&& rg, const Alloc&); // since C++23
+ template <class Alloc>
+ priority_queue(const priority_queue& q, const Alloc& a);
+ template <class Alloc>
+ priority_queue(priority_queue&& q, const Alloc& a);
+
+ bool empty() const;
+ size_type size() const;
+ const_reference top() const;
+
+ void push(const value_type& v);
+ void push(value_type&& v);
+ template<container-compatible-range<T> R>
+ void push_range(R&& rg); // C++23
+ template <class... Args> void emplace(Args&&... args);
+ void pop();
+
+ void swap(priority_queue& q)
+ noexcept(is_nothrow_swappable_v<Container> &&
+ is_nothrow_swappable_v<Comp>)
+};
+
+template <class Compare, class Container>
+priority_queue(Compare, Container)
+ -> priority_queue<typename Container::value_type, Container, Compare>; // C++17
+
+template<class InputIterator,
+ class Compare = less<iter-value-type<InputIterator>>,
+ class Container = vector<iter-value-type<InputIterator>>>
+priority_queue(InputIterator, InputIterator, Compare = Compare(), Container = Container())
+ -> priority_queue<iter-value-type<InputIterator>, Container, Compare>; // C++17
+
+template<ranges::input_range R, class Compare = less<ranges::range_value_t<R>>>
+ priority_queue(from_range_t, R&&, Compare = Compare())
+ -> priority_queue<ranges::range_value_t<R>, vector<ranges::range_value_t<R>>, Compare>; // C++23
+
+template<class Compare, class Container, class Allocator>
+priority_queue(Compare, Container, Allocator)
+ -> priority_queue<typename Container::value_type, Container, Compare>; // C++17
+
+template<class InputIterator, class Allocator>
+priority_queue(InputIterator, InputIterator, Allocator)
+ -> priority_queue<iter-value-type<InputIterator>,
+ vector<iter-value-type<InputIterator>, Allocator>,
+ less<iter-value-type<InputIterator>>>; // C++17
+
+template<class InputIterator, class Compare, class Allocator>
+priority_queue(InputIterator, InputIterator, Compare, Allocator)
+ -> priority_queue<iter-value-type<InputIterator>,
+ vector<iter-value-type<InputIterator>, Allocator>, Compare>; // C++17
+
+template<class InputIterator, class Compare, class Container, class Allocator>
+priority_queue(InputIterator, InputIterator, Compare, Container, Allocator)
+ -> priority_queue<typename Container::value_type, Container, Compare>; // C++17
+
+template<ranges::input_range R, class Compare, class Allocator>
+ priority_queue(from_range_t, R&&, Compare, Allocator)
+ -> priority_queue<ranges::range_value_t<R>, vector<ranges::range_value_t<R>, Allocator>,
+ Compare>; // C++23
+
+template<ranges::input_range R, class Allocator>
+ priority_queue(from_range_t, R&&, Allocator)
+ -> priority_queue<ranges::range_value_t<R>, vector<ranges::range_value_t<R>, Allocator>>; // C++23
+
+template <class T, class Container, class Compare>
+ void swap(priority_queue<T, Container, Compare>& x,
+ priority_queue<T, Container, Compare>& y)
+ noexcept(noexcept(x.swap(y)));
+
+} // std
+
+*/
+
+#include <__algorithm/make_heap.h>
+#include <__algorithm/pop_heap.h>
+#include <__algorithm/push_heap.h>
+#include <__algorithm/ranges_copy.h>
+#include <__config>
+#include <__functional/operations.h>
+#include <__fwd/deque.h>
+#include <__fwd/queue.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/uses_allocator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__utility/forward.h>
+#include <deque>
+#include <vector>
+#include <version>
+
+// standard-mandated includes
+
+// [queue.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Container>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y);
+
+template <class _Tp, class _Container>
+_LIBCPP_HIDE_FROM_ABI bool operator<(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y);
+
+template <class _Tp, class _Container /*= deque<_Tp>*/>
+class _LIBCPP_TEMPLATE_VIS queue {
+public:
+ typedef _Container container_type;
+ typedef typename container_type::value_type value_type;
+ typedef typename container_type::reference reference;
+ typedef typename container_type::const_reference const_reference;
+ typedef typename container_type::size_type size_type;
+ static_assert(is_same<_Tp, value_type>::value, "");
+
+protected:
+ container_type c;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI queue() _NOEXCEPT_(is_nothrow_default_constructible<container_type>::value) : c() {}
+
+ _LIBCPP_HIDE_FROM_ABI queue(const queue& __q) : c(__q.c) {}
+
+#if _LIBCPP_STD_VER >= 23
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI queue(_InputIterator __first, _InputIterator __last) : c(__first, __last) {}
+
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI queue(from_range_t, _Range&& __range) : c(from_range, std::forward<_Range>(__range)) {}
+
+ template <class _InputIterator,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0,
+ __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI queue(_InputIterator __first, _InputIterator __second, const _Alloc& __alloc)
+ : c(__first, __second, __alloc) {}
+
+ template <_ContainerCompatibleRange<_Tp> _Range,
+ class _Alloc,
+ __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI queue(from_range_t, _Range&& __range, const _Alloc& __alloc)
+ : c(from_range, std::forward<_Range>(__range), __alloc) {}
+
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI queue& operator=(const queue& __q) {
+ c = __q.c;
+ return *this;
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI queue(queue&& __q) noexcept(is_nothrow_move_constructible<container_type>::value)
+ : c(std::move(__q.c)) {}
+
+ _LIBCPP_HIDE_FROM_ABI queue& operator=(queue&& __q) noexcept(is_nothrow_move_assignable<container_type>::value) {
+ c = std::move(__q.c);
+ return *this;
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI explicit queue(const container_type& __c) : c(__c) {}
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI explicit queue(container_type&& __c) : c(std::move(__c)) {}
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit queue(const _Alloc& __a) : c(__a) {}
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI queue(const queue& __q, const _Alloc& __a) : c(__q.c, __a) {}
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI queue(const container_type& __c, const _Alloc& __a) : c(__c, __a) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI queue(container_type&& __c, const _Alloc& __a) : c(std::move(__c), __a) {}
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI queue(queue&& __q, const _Alloc& __a) : c(std::move(__q.c), __a) {}
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const { return c.empty(); }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const { return c.size(); }
+
+ _LIBCPP_HIDE_FROM_ABI reference front() { return c.front(); }
+ _LIBCPP_HIDE_FROM_ABI const_reference front() const { return c.front(); }
+ _LIBCPP_HIDE_FROM_ABI reference back() { return c.back(); }
+ _LIBCPP_HIDE_FROM_ABI const_reference back() const { return c.back(); }
+
+ _LIBCPP_HIDE_FROM_ABI void push(const value_type& __v) { c.push_back(__v); }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void push(value_type&& __v) { c.push_back(std::move(__v)); }
+
+# if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void push_range(_Range&& __range) {
+ if constexpr (requires(container_type& __c) { __c.append_range(std::forward<_Range>(__range)); }) {
+ c.append_range(std::forward<_Range>(__range));
+ } else {
+ ranges::copy(std::forward<_Range>(__range), std::back_inserter(c));
+ }
+ }
+# endif
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI
+# if _LIBCPP_STD_VER >= 17
+ decltype(auto)
+ emplace(_Args&&... __args) {
+ return c.emplace_back(std::forward<_Args>(__args)...);
+ }
+# else
+ void
+ emplace(_Args&&... __args) {
+ c.emplace_back(std::forward<_Args>(__args)...);
+ }
+# endif
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void pop() { c.pop_front(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(queue& __q) _NOEXCEPT_(__is_nothrow_swappable_v<container_type>) {
+ using std::swap;
+ swap(c, __q.c);
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI const _Container& __get_container() const { return c; }
+
+ template <class _T1, class _OtherContainer>
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const queue<_T1, _OtherContainer>& __x, const queue<_T1, _OtherContainer>& __y);
+
+ template <class _T1, class _OtherContainer>
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator<(const queue<_T1, _OtherContainer>& __x, const queue<_T1, _OtherContainer>& __y);
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Container, class = enable_if_t<!__is_allocator<_Container>::value> >
+queue(_Container) -> queue<typename _Container::value_type, _Container>;
+
+template <class _Container,
+ class _Alloc,
+ class = enable_if_t<!__is_allocator<_Container>::value>,
+ class = enable_if_t<uses_allocator<_Container, _Alloc>::value> >
+queue(_Container, _Alloc) -> queue<typename _Container::value_type, _Container>;
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+queue(_InputIterator, _InputIterator) -> queue<__iter_value_type<_InputIterator>>;
+
+template <ranges::input_range _Range>
+queue(from_range_t, _Range&&) -> queue<ranges::range_value_t<_Range>>;
+
+template <class _InputIterator,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0,
+ __enable_if_t<__is_allocator<_Alloc>::value, int> = 0>
+queue(_InputIterator,
+ _InputIterator,
+ _Alloc) -> queue<__iter_value_type<_InputIterator>, deque<__iter_value_type<_InputIterator>, _Alloc>>;
+
+template <ranges::input_range _Range, class _Alloc, __enable_if_t<__is_allocator<_Alloc>::value, int> = 0>
+queue(from_range_t,
+ _Range&&,
+ _Alloc) -> queue<ranges::range_value_t<_Range>, deque<ranges::range_value_t<_Range>, _Alloc>>;
+#endif
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) {
+ return __x.c == __y.c;
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) {
+ return __x.c < __y.c;
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) {
+ return __y < __x;
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) {
+ return !(__y < __x);
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp, three_way_comparable _Container>
+_LIBCPP_HIDE_FROM_ABI compare_three_way_result_t<_Container>
+operator<=>(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) {
+ // clang 16 bug: declaring `friend operator<=>` causes "use of overloaded operator '*' is ambiguous" errors
+ return __x.__get_container() <=> __y.__get_container();
+}
+
+#endif
+
+template <class _Tp, class _Container, __enable_if_t<__is_swappable_v<_Container>, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void swap(queue<_Tp, _Container>& __x, queue<_Tp, _Container>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+template <class _Tp, class _Container, class _Alloc>
+struct _LIBCPP_TEMPLATE_VIS uses_allocator<queue<_Tp, _Container>, _Alloc> : public uses_allocator<_Container, _Alloc> {
+};
+
+template <class _Tp, class _Container, class _Compare>
+class _LIBCPP_TEMPLATE_VIS priority_queue {
+public:
+ typedef _Container container_type;
+ typedef _Compare value_compare;
+ typedef typename container_type::value_type value_type;
+ typedef typename container_type::reference reference;
+ typedef typename container_type::const_reference const_reference;
+ typedef typename container_type::size_type size_type;
+ static_assert(is_same<_Tp, value_type>::value, "");
+
+protected:
+ container_type c;
+ value_compare comp;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI priority_queue() _NOEXCEPT_(
+ is_nothrow_default_constructible<container_type>::value&& is_nothrow_default_constructible<value_compare>::value)
+ : c(), comp() {}
+
+ _LIBCPP_HIDE_FROM_ABI priority_queue(const priority_queue& __q) : c(__q.c), comp(__q.comp) {}
+
+ _LIBCPP_HIDE_FROM_ABI priority_queue& operator=(const priority_queue& __q) {
+ c = __q.c;
+ comp = __q.comp;
+ return *this;
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI priority_queue(priority_queue&& __q) noexcept(
+ is_nothrow_move_constructible<container_type>::value && is_nothrow_move_constructible<value_compare>::value)
+ : c(std::move(__q.c)), comp(std::move(__q.comp)) {}
+
+ _LIBCPP_HIDE_FROM_ABI priority_queue& operator=(priority_queue&& __q) noexcept(
+ is_nothrow_move_assignable<container_type>::value && is_nothrow_move_assignable<value_compare>::value) {
+ c = std::move(__q.c);
+ comp = std::move(__q.comp);
+ return *this;
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI explicit priority_queue(const value_compare& __comp) : c(), comp(__comp) {}
+ _LIBCPP_HIDE_FROM_ABI priority_queue(const value_compare& __comp, const container_type& __c);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI priority_queue(const value_compare& __comp, container_type&& __c);
+#endif
+ template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(_InputIter __f, _InputIter __l, const value_compare& __comp = value_compare());
+
+ template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ priority_queue(_InputIter __f, _InputIter __l, const value_compare& __comp, const container_type& __c);
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ priority_queue(_InputIter __f, _InputIter __l, const value_compare& __comp, container_type&& __c);
+#endif // _LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(from_range_t, _Range&& __range, const value_compare& __comp = value_compare())
+ : c(from_range, std::forward<_Range>(__range)), comp(__comp) {
+ std::make_heap(c.begin(), c.end(), comp);
+ }
+#endif
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit priority_queue(const _Alloc& __a);
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(const value_compare& __comp, const _Alloc& __a);
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(const value_compare& __comp, const container_type& __c, const _Alloc& __a);
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(const priority_queue& __q, const _Alloc& __a);
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(const value_compare& __comp, container_type&& __c, const _Alloc& __a);
+
+ template <class _Alloc, __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(priority_queue&& __q, const _Alloc& __a);
+#endif // _LIBCPP_CXX03_LANG
+
+ template <
+ class _InputIter,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<container_type, _Alloc>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(_InputIter __f, _InputIter __l, const _Alloc& __a);
+
+ template <
+ class _InputIter,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<container_type, _Alloc>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(_InputIter __f, _InputIter __l, const value_compare& __comp, const _Alloc& __a);
+
+ template <
+ class _InputIter,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<container_type, _Alloc>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(
+ _InputIter __f, _InputIter __l, const value_compare& __comp, const container_type& __c, const _Alloc& __a);
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <
+ class _InputIter,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<container_type, _Alloc>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ priority_queue(_InputIter __f, _InputIter __l, const value_compare& __comp, container_type&& __c, const _Alloc& __a);
+#endif // _LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 23
+
+ template <_ContainerCompatibleRange<_Tp> _Range,
+ class _Alloc,
+ class = enable_if_t<uses_allocator<_Container, _Alloc>::value>>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(from_range_t, _Range&& __range, const value_compare& __comp, const _Alloc& __a)
+ : c(from_range, std::forward<_Range>(__range), __a), comp(__comp) {
+ std::make_heap(c.begin(), c.end(), comp);
+ }
+
+ template <_ContainerCompatibleRange<_Tp> _Range,
+ class _Alloc,
+ class = enable_if_t<uses_allocator<_Container, _Alloc>::value>>
+ _LIBCPP_HIDE_FROM_ABI priority_queue(from_range_t, _Range&& __range, const _Alloc& __a)
+ : c(from_range, std::forward<_Range>(__range), __a), comp() {
+ std::make_heap(c.begin(), c.end(), comp);
+ }
+
+#endif
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const { return c.empty(); }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const { return c.size(); }
+ _LIBCPP_HIDE_FROM_ABI const_reference top() const { return c.front(); }
+
+ _LIBCPP_HIDE_FROM_ABI void push(const value_type& __v);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void push(value_type&& __v);
+
+# if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void push_range(_Range&& __range) {
+ if constexpr (requires(container_type& __c) { __c.append_range(std::forward<_Range>(__range)); }) {
+ c.append_range(std::forward<_Range>(__range));
+ } else {
+ ranges::copy(std::forward<_Range>(__range), std::back_inserter(c));
+ }
+
+ std::make_heap(c.begin(), c.end(), comp);
+ }
+# endif
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void emplace(_Args&&... __args);
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void pop();
+
+ _LIBCPP_HIDE_FROM_ABI void swap(priority_queue& __q)
+ _NOEXCEPT_(__is_nothrow_swappable_v<container_type>&& __is_nothrow_swappable_v<value_compare>);
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI const _Container& __get_container() const { return c; }
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Compare,
+ class _Container,
+ class = enable_if_t<!__is_allocator<_Compare>::value>,
+ class = enable_if_t<!__is_allocator<_Container>::value> >
+priority_queue(_Compare, _Container) -> priority_queue<typename _Container::value_type, _Container, _Compare>;
+
+template <class _InputIterator,
+ class _Compare = less<__iter_value_type<_InputIterator>>,
+ class _Container = vector<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Compare>::value>,
+ class = enable_if_t<!__is_allocator<_Container>::value> >
+priority_queue(_InputIterator, _InputIterator, _Compare = _Compare(), _Container = _Container())
+ -> priority_queue<__iter_value_type<_InputIterator>, _Container, _Compare>;
+
+template <class _Compare,
+ class _Container,
+ class _Alloc,
+ class = enable_if_t<!__is_allocator<_Compare>::value>,
+ class = enable_if_t<!__is_allocator<_Container>::value>,
+ class = enable_if_t<uses_allocator<_Container, _Alloc>::value> >
+priority_queue(_Compare, _Container, _Alloc) -> priority_queue<typename _Container::value_type, _Container, _Compare>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value> >
+priority_queue(_InputIterator, _InputIterator, _Allocator)
+ -> priority_queue<__iter_value_type<_InputIterator>,
+ vector<__iter_value_type<_InputIterator>, _Allocator>,
+ less<__iter_value_type<_InputIterator>>>;
+
+template <class _InputIterator,
+ class _Compare,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Compare>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value> >
+priority_queue(_InputIterator, _InputIterator, _Compare, _Allocator)
+ -> priority_queue<__iter_value_type<_InputIterator>,
+ vector<__iter_value_type<_InputIterator>, _Allocator>,
+ _Compare>;
+
+template <class _InputIterator,
+ class _Compare,
+ class _Container,
+ class _Alloc,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Compare>::value>,
+ class = enable_if_t<!__is_allocator<_Container>::value>,
+ class = enable_if_t<uses_allocator<_Container, _Alloc>::value> >
+priority_queue(_InputIterator, _InputIterator, _Compare, _Container, _Alloc)
+ -> priority_queue<typename _Container::value_type, _Container, _Compare>;
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+
+template <ranges::input_range _Range,
+ class _Compare = less<ranges::range_value_t<_Range>>,
+ class = enable_if_t<!__is_allocator<_Compare>::value>>
+priority_queue(from_range_t, _Range&&, _Compare = _Compare())
+ -> priority_queue<ranges::range_value_t<_Range>, vector<ranges::range_value_t<_Range>>, _Compare>;
+
+template <ranges::input_range _Range,
+ class _Compare,
+ class _Alloc,
+ class = enable_if_t<!__is_allocator<_Compare>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value>>
+priority_queue(from_range_t, _Range&&, _Compare, _Alloc)
+ -> priority_queue<ranges::range_value_t<_Range>, vector<ranges::range_value_t<_Range>, _Alloc>, _Compare>;
+
+template <ranges::input_range _Range, class _Alloc, class = enable_if_t<__is_allocator<_Alloc>::value>>
+priority_queue(from_range_t, _Range&&, _Alloc)
+ -> priority_queue<ranges::range_value_t<_Range>, vector<ranges::range_value_t<_Range>, _Alloc>>;
+
+#endif
+
+template <class _Tp, class _Container, class _Compare>
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const _Compare& __comp, const container_type& __c)
+ : c(__c), comp(__comp) {
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const value_compare& __comp, container_type&& __c)
+ : c(std::move(__c)), comp(__comp) {
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
+ _InputIter __f, _InputIter __l, const value_compare& __comp)
+ : c(__f, __l), comp(__comp) {
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+template <class _Tp, class _Container, class _Compare>
+template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
+ _InputIter __f, _InputIter __l, const value_compare& __comp, const container_type& __c)
+ : c(__c), comp(__comp) {
+ c.insert(c.end(), __f, __l);
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
+ _InputIter __f, _InputIter __l, const value_compare& __comp, container_type&& __c)
+ : c(std::move(__c)), comp(__comp) {
+ c.insert(c.end(), __f, __l);
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const _Alloc& __a) : c(__a) {}
+
+template <class _Tp, class _Container, class _Compare>
+template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const value_compare& __comp, const _Alloc& __a)
+ : c(__a), comp(__comp) {}
+
+template <class _Tp, class _Container, class _Compare>
+template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
+ const value_compare& __comp, const container_type& __c, const _Alloc& __a)
+ : c(__c, __a), comp(__comp) {
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+template <class _Tp, class _Container, class _Compare>
+template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const priority_queue& __q, const _Alloc& __a)
+ : c(__q.c, __a), comp(__q.comp) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
+ const value_compare& __comp, container_type&& __c, const _Alloc& __a)
+ : c(std::move(__c), __a), comp(__comp) {
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+template <class _Tp, class _Container, class _Compare>
+template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(priority_queue&& __q, const _Alloc& __a)
+ : c(std::move(__q.c), __a), comp(std::move(__q.comp)) {}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+template <
+ class _InputIter,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(_InputIter __f, _InputIter __l, const _Alloc& __a)
+ : c(__f, __l, __a), comp() {
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+template <class _Tp, class _Container, class _Compare>
+template <
+ class _InputIter,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
+ _InputIter __f, _InputIter __l, const value_compare& __comp, const _Alloc& __a)
+ : c(__f, __l, __a), comp(__comp) {
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+template <class _Tp, class _Container, class _Compare>
+template <
+ class _InputIter,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
+ _InputIter __f, _InputIter __l, const value_compare& __comp, const container_type& __c, const _Alloc& __a)
+ : c(__c, __a), comp(__comp) {
+ c.insert(c.end(), __f, __l);
+ std::make_heap(c.begin(), c.end(), comp);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Tp, class _Container, class _Compare>
+template <
+ class _InputIter,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<_Container, _Alloc>::value, int> >
+inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
+ _InputIter __f, _InputIter __l, const value_compare& __comp, container_type&& __c, const _Alloc& __a)
+ : c(std::move(__c), __a), comp(__comp) {
+ c.insert(c.end(), __f, __l);
+ std::make_heap(c.begin(), c.end(), comp);
+}
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+inline void priority_queue<_Tp, _Container, _Compare>::push(const value_type& __v) {
+ c.push_back(__v);
+ std::push_heap(c.begin(), c.end(), comp);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+inline void priority_queue<_Tp, _Container, _Compare>::push(value_type&& __v) {
+ c.push_back(std::move(__v));
+ std::push_heap(c.begin(), c.end(), comp);
+}
+
+template <class _Tp, class _Container, class _Compare>
+template <class... _Args>
+inline void priority_queue<_Tp, _Container, _Compare>::emplace(_Args&&... __args) {
+ c.emplace_back(std::forward<_Args>(__args)...);
+ std::push_heap(c.begin(), c.end(), comp);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Container, class _Compare>
+inline void priority_queue<_Tp, _Container, _Compare>::pop() {
+ std::pop_heap(c.begin(), c.end(), comp);
+ c.pop_back();
+}
+
+template <class _Tp, class _Container, class _Compare>
+inline void priority_queue<_Tp, _Container, _Compare>::swap(priority_queue& __q)
+ _NOEXCEPT_(__is_nothrow_swappable_v<container_type>&& __is_nothrow_swappable_v<value_compare>) {
+ using std::swap;
+ swap(c, __q.c);
+ swap(comp, __q.comp);
+}
+
+template <class _Tp,
+ class _Container,
+ class _Compare,
+ __enable_if_t<__is_swappable_v<_Container> && __is_swappable_v<_Compare>, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(priority_queue<_Tp, _Container, _Compare>& __x, priority_queue<_Tp, _Container, _Compare>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+template <class _Tp, class _Container, class _Compare, class _Alloc>
+struct _LIBCPP_TEMPLATE_VIS uses_allocator<priority_queue<_Tp, _Container, _Compare>, _Alloc>
+ : public uses_allocator<_Container, _Alloc> {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <cstdlib>
+# include <functional>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_QUEUE
diff --git a/libcxx/include/__cxx03/random b/libcxx/include/__cxx03/random
new file mode 100644
index 00000000000000..6cc3760c20e16c
--- /dev/null
+++ b/libcxx/include/__cxx03/random
@@ -0,0 +1,1742 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_RANDOM
+#define _LIBCPP_RANDOM
+
+/*
+ random synopsis
+
+#include <initializer_list>
+
+namespace std
+{
+// [rand.req.urng], uniform random bit generator requirements
+template<class G>
+concept uniform_random_bit_generator = see below; // C++20
+
+// Engines
+
+template <class UIntType, UIntType a, UIntType c, UIntType m>
+class linear_congruential_engine
+{
+public:
+ // types
+ typedef UIntType result_type;
+
+ // engine characteristics
+ static constexpr result_type multiplier = a;
+ static constexpr result_type increment = c;
+ static constexpr result_type modulus = m;
+ static constexpr result_type min() { return c == 0u ? 1u: 0u;}
+ static constexpr result_type max() { return m - 1u;}
+ static constexpr result_type default_seed = 1u;
+
+ // constructors and seeding functions
+ explicit linear_congruential_engine(result_type s = default_seed); // before C++20
+ linear_congruential_engine() : linear_congruential_engine(default_seed) {} // C++20
+ explicit linear_congruential_engine(result_type s); // C++20
+ template<class Sseq> explicit linear_congruential_engine(Sseq& q);
+ void seed(result_type s = default_seed);
+ template<class Sseq> void seed(Sseq& q);
+
+ // generating functions
+ result_type operator()();
+ void discard(unsigned long long z);
+};
+
+template <class UIntType, UIntType a, UIntType c, UIntType m>
+bool
+operator==(const linear_congruential_engine<UIntType, a, c, m>& x,
+ const linear_congruential_engine<UIntType, a, c, m>& y);
+
+template <class UIntType, UIntType a, UIntType c, UIntType m>
+bool
+operator!=(const linear_congruential_engine<UIntType, a, c, m>& x,
+ const linear_congruential_engine<UIntType, a, c, m>& y);
+
+template <class charT, class traits,
+ class UIntType, UIntType a, UIntType c, UIntType m>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& os,
+ const linear_congruential_engine<UIntType, a, c, m>& x);
+
+template <class charT, class traits,
+ class UIntType, UIntType a, UIntType c, UIntType m>
+basic_istream<charT, traits>&
+operator>>(basic_istream<charT, traits>& is,
+ linear_congruential_engine<UIntType, a, c, m>& x);
+
+template <class UIntType, size_t w, size_t n, size_t m, size_t r,
+ UIntType a, size_t u, UIntType d, size_t s,
+ UIntType b, size_t t, UIntType c, size_t l, UIntType f>
+class mersenne_twister_engine
+{
+public:
+ // types
+ typedef UIntType result_type;
+
+ // engine characteristics
+ static constexpr size_t word_size = w;
+ static constexpr size_t state_size = n;
+ static constexpr size_t shift_size = m;
+ static constexpr size_t mask_bits = r;
+ static constexpr result_type xor_mask = a;
+ static constexpr size_t tempering_u = u;
+ static constexpr result_type tempering_d = d;
+ static constexpr size_t tempering_s = s;
+ static constexpr result_type tempering_b = b;
+ static constexpr size_t tempering_t = t;
+ static constexpr result_type tempering_c = c;
+ static constexpr size_t tempering_l = l;
+ static constexpr result_type initialization_multiplier = f;
+ static constexpr result_type min () { return 0; }
+ static constexpr result_type max() { return 2^w - 1; }
+ static constexpr result_type default_seed = 5489u;
+
+ // constructors and seeding functions
+ explicit mersenne_twister_engine(result_type s = default_seed); // before C++20
+ mersenne_twister_engine() : mersenne_twister_engine(default_seed) {} // C++20
+ explicit mersenne_twister_engine(result_type s); // C++20
+ template<class Sseq> explicit mersenne_twister_engine(Sseq& q);
+ void seed(result_type value = default_seed);
+ template<class Sseq> void seed(Sseq& q);
+
+ // generating functions
+ result_type operator()();
+ void discard(unsigned long long z);
+};
+
+template <class UIntType, size_t w, size_t n, size_t m, size_t r,
+ UIntType a, size_t u, UIntType d, size_t s,
+ UIntType b, size_t t, UIntType c, size_t l, UIntType f>
+bool
+operator==(
+ const mersenne_twister_engine<UIntType, w, n, m, r, a, u, d, s, b, t, c, l, f>& x,
+ const mersenne_twister_engine<UIntType, w, n, m, r, a, u, d, s, b, t, c, l, f>& y);
+
+template <class UIntType, size_t w, size_t n, size_t m, size_t r,
+ UIntType a, size_t u, UIntType d, size_t s,
+ UIntType b, size_t t, UIntType c, size_t l, UIntType f>
+bool
+operator!=(
+ const mersenne_twister_engine<UIntType, w, n, m, r, a, u, d, s, b, t, c, l, f>& x,
+ const mersenne_twister_engine<UIntType, w, n, m, r, a, u, d, s, b, t, c, l, f>& y);
+
+template <class charT, class traits,
+ class UIntType, size_t w, size_t n, size_t m, size_t r,
+ UIntType a, size_t u, UIntType d, size_t s,
+ UIntType b, size_t t, UIntType c, size_t l, UIntType f>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& os,
+ const mersenne_twister_engine<UIntType, w, n, m, r, a, u, d, s, b, t, c, l, f>& x);
+
+template <class charT, class traits,
+ class UIntType, size_t w, size_t n, size_t m, size_t r,
+ UIntType a, size_t u, UIntType d, size_t s,
+ UIntType b, size_t t, UIntType c, size_t l, UIntType f>
+basic_istream<charT, traits>&
+operator>>(basic_istream<charT, traits>& is,
+ mersenne_twister_engine<UIntType, w, n, m, r, a, u, d, s, b, t, c, l, f>& x);
+
+template<class UIntType, size_t w, size_t s, size_t r>
+class subtract_with_carry_engine
+{
+public:
+ // types
+ typedef UIntType result_type;
+
+ // engine characteristics
+ static constexpr size_t word_size = w;
+ static constexpr size_t short_lag = s;
+ static constexpr size_t long_lag = r;
+ static constexpr result_type min() { return 0; }
+ static constexpr result_type max() { return m-1; }
+ static constexpr result_type default_seed = 19780503u;
+
+ // constructors and seeding functions
+ explicit subtract_with_carry_engine(result_type value = default_seed); // before C++20
+ subtract_with_carry_engine() : subtract_with_carry_engine(default_seed) {} // C++20
+ explicit subtract_with_carry_engine(result_type value); // C++20
+ template<class Sseq> explicit subtract_with_carry_engine(Sseq& q);
+ void seed(result_type value = default_seed);
+ template<class Sseq> void seed(Sseq& q);
+
+ // generating functions
+ result_type operator()();
+ void discard(unsigned long long z);
+};
+
+template<class UIntType, size_t w, size_t s, size_t r>
+bool
+operator==(
+ const subtract_with_carry_engine<UIntType, w, s, r>& x,
+ const subtract_with_carry_engine<UIntType, w, s, r>& y);
+
+template<class UIntType, size_t w, size_t s, size_t r>
+bool
+operator!=(
+ const subtract_with_carry_engine<UIntType, w, s, r>& x,
+ const subtract_with_carry_engine<UIntType, w, s, r>& y);
+
+template <class charT, class traits,
+ class UIntType, size_t w, size_t s, size_t r>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& os,
+ const subtract_with_carry_engine<UIntType, w, s, r>& x);
+
+template <class charT, class traits,
+ class UIntType, size_t w, size_t s, size_t r>
+basic_istream<charT, traits>&
+operator>>(basic_istream<charT, traits>& is,
+ subtract_with_carry_engine<UIntType, w, s, r>& x);
+
+template<class Engine, size_t p, size_t r>
+class discard_block_engine
+{
+public:
+ // types
+ typedef typename Engine::result_type result_type;
+
+ // engine characteristics
+ static constexpr size_t block_size = p;
+ static constexpr size_t used_block = r;
+ static constexpr result_type min() { return Engine::min(); }
+ static constexpr result_type max() { return Engine::max(); }
+
+ // constructors and seeding functions
+ discard_block_engine();
+ explicit discard_block_engine(const Engine& e);
+ explicit discard_block_engine(Engine&& e);
+ explicit discard_block_engine(result_type s);
+ template<class Sseq> explicit discard_block_engine(Sseq& q);
+ void seed();
+ void seed(result_type s);
+ template<class Sseq> void seed(Sseq& q);
+
+ // generating functions
+ result_type operator()();
+ void discard(unsigned long long z);
+
+ // property functions
+ const Engine& base() const noexcept;
+};
+
+template<class Engine, size_t p, size_t r>
+bool
+operator==(
+ const discard_block_engine<Engine, p, r>& x,
+ const discard_block_engine<Engine, p, r>& y);
+
+template<class Engine, size_t p, size_t r>
+bool
+operator!=(
+ const discard_block_engine<Engine, p, r>& x,
+ const discard_block_engine<Engine, p, r>& y);
+
+template <class charT, class traits,
+ class Engine, size_t p, size_t r>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& os,
+ const discard_block_engine<Engine, p, r>& x);
+
+template <class charT, class traits,
+ class Engine, size_t p, size_t r>
+basic_istream<charT, traits>&
+operator>>(basic_istream<charT, traits>& is,
+ discard_block_engine<Engine, p, r>& x);
+
+template<class Engine, size_t w, class UIntType>
+class independent_bits_engine
+{
+public:
+ // types
+ typedef UIntType result_type;
+
+ // engine characteristics
+ static constexpr result_type min() { return 0; }
+ static constexpr result_type max() { return 2^w - 1; }
+
+ // constructors and seeding functions
+ independent_bits_engine();
+ explicit independent_bits_engine(const Engine& e);
+ explicit independent_bits_engine(Engine&& e);
+ explicit independent_bits_engine(result_type s);
+ template<class Sseq> explicit independent_bits_engine(Sseq& q);
+ void seed();
+ void seed(result_type s);
+ template<class Sseq> void seed(Sseq& q);
+
+ // generating functions
+ result_type operator()(); void discard(unsigned long long z);
+
+ // property functions
+ const Engine& base() const noexcept;
+};
+
+template<class Engine, size_t w, class UIntType>
+bool
+operator==(
+ const independent_bits_engine<Engine, w, UIntType>& x,
+ const independent_bits_engine<Engine, w, UIntType>& y);
+
+template<class Engine, size_t w, class UIntType>
+bool
+operator!=(
+ const independent_bits_engine<Engine, w, UIntType>& x,
+ const independent_bits_engine<Engine, w, UIntType>& y);
+
+template <class charT, class traits,
+ class Engine, size_t w, class UIntType>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& os,
+ const independent_bits_engine<Engine, w, UIntType>& x);
+
+template <class charT, class traits,
+ class Engine, size_t w, class UIntType>
+basic_istream<charT, traits>&
+operator>>(basic_istream<charT, traits>& is,
+ independent_bits_engine<Engine, w, UIntType>& x);
+
+template<class Engine, size_t k>
+class shuffle_order_engine
+{
+public:
+ // types
+ typedef typename Engine::result_type result_type;
+
+ // engine characteristics
+ static constexpr size_t table_size = k;
+ static constexpr result_type min() { return Engine::min; }
+ static constexpr result_type max() { return Engine::max; }
+
+ // constructors and seeding functions
+ shuffle_order_engine();
+ explicit shuffle_order_engine(const Engine& e);
+ explicit shuffle_order_engine(Engine&& e);
+ explicit shuffle_order_engine(result_type s);
+ template<class Sseq> explicit shuffle_order_engine(Sseq& q);
+ void seed();
+ void seed(result_type s);
+ template<class Sseq> void seed(Sseq& q);
+
+ // generating functions
+ result_type operator()();
+ void discard(unsigned long long z);
+
+ // property functions
+ const Engine& base() const noexcept;
+};
+
+template<class Engine, size_t k>
+bool
+operator==(
+ const shuffle_order_engine<Engine, k>& x,
+ const shuffle_order_engine<Engine, k>& y);
+
+template<class Engine, size_t k>
+bool
+operator!=(
+ const shuffle_order_engine<Engine, k>& x,
+ const shuffle_order_engine<Engine, k>& y);
+
+template <class charT, class traits,
+ class Engine, size_t k>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& os,
+ const shuffle_order_engine<Engine, k>& x);
+
+template <class charT, class traits,
+ class Engine, size_t k>
+basic_istream<charT, traits>&
+operator>>(basic_istream<charT, traits>& is,
+ shuffle_order_engine<Engine, k>& x);
+
+typedef linear_congruential_engine<uint_fast32_t, 16807, 0, 2147483647>
+ minstd_rand0;
+typedef linear_congruential_engine<uint_fast32_t, 48271, 0, 2147483647>
+ minstd_rand;
+typedef mersenne_twister_engine<uint_fast32_t, 32, 624, 397, 31,
+ 0x9908b0df,
+ 11, 0xffffffff,
+ 7, 0x9d2c5680,
+ 15, 0xefc60000,
+ 18, 1812433253> mt19937;
+typedef mersenne_twister_engine<uint_fast64_t, 64, 312, 156, 31,
+ 0xb5026f5aa96619e9,
+ 29, 0x5555555555555555,
+ 17, 0x71d67fffeda60000,
+ 37, 0xfff7eee000000000,
+ 43, 6364136223846793005> mt19937_64;
+typedef subtract_with_carry_engine<uint_fast32_t, 24, 10, 24> ranlux24_base;
+typedef subtract_with_carry_engine<uint_fast64_t, 48, 5, 12> ranlux48_base;
+typedef discard_block_engine<ranlux24_base, 223, 23> ranlux24;
+typedef discard_block_engine<ranlux48_base, 389, 11> ranlux48;
+typedef shuffle_order_engine<minstd_rand0, 256> knuth_b;
+typedef minstd_rand default_random_engine;
+
+// Generators
+
+class random_device
+{
+public:
+ // types
+ typedef unsigned int result_type;
+
+ // generator characteristics
+ static constexpr result_type min() { return numeric_limits<result_type>::min(); }
+ static constexpr result_type max() { return numeric_limits<result_type>::max(); }
+
+ // constructors
+ explicit random_device(const string& token = implementation-defined); // before C++20
+ random_device() : random_device(implementation-defined) {} // C++20
+ explicit random_device(const string& token); // C++20
+
+ // generating functions
+ result_type operator()();
+
+ // property functions
+ double entropy() const noexcept;
+
+ // no copy functions
+ random_device(const random_device& ) = delete;
+ void operator=(const random_device& ) = delete;
+};
+
+// Utilities
+
+class seed_seq
+{
+public:
+ // types
+ typedef uint_least32_t result_type;
+
+ // constructors
+ seed_seq();
+ template<class T>
+ seed_seq(initializer_list<T> il);
+ template<class InputIterator>
+ seed_seq(InputIterator begin, InputIterator end);
+
+ // generating functions
+ template<class RandomAccessIterator>
+ void generate(RandomAccessIterator begin, RandomAccessIterator end);
+
+ // property functions
+ size_t size() const;
+ template<class OutputIterator>
+ void param(OutputIterator dest) const;
+
+ // no copy functions
+ seed_seq(const seed_seq&) = delete;
+ void operator=(const seed_seq& ) = delete;
+};
+
+template<class RealType, size_t bits, class URNG>
+ RealType generate_canonical(URNG& g);
+
+// Distributions
+
+template<class IntType = int>
+class uniform_int_distribution
+{
+public:
+ // types
+ typedef IntType result_type;
+
+ class param_type
+ {
+ public:
+ typedef uniform_int_distribution distribution_type;
+
+ explicit param_type(IntType a = 0,
+ IntType b = numeric_limits<IntType>::max());
+
+ result_type a() const;
+ result_type b() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit uniform_int_distribution(IntType a = 0,
+ IntType b = numeric_limits<IntType>::max()); // before C++20
+ uniform_int_distribution() : uniform_int_distribution(0) {} // C++20
+ explicit uniform_int_distribution(IntType a,
+ IntType b = numeric_limits<IntType>::max()); // C++20
+ explicit uniform_int_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type a() const;
+ result_type b() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const uniform_int_distribution& x,
+ const uniform_int_distribution& y);
+ friend bool operator!=(const uniform_int_distribution& x,
+ const uniform_int_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const uniform_int_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ uniform_int_distribution& x);
+};
+
+template<class RealType = double>
+class uniform_real_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef uniform_real_distribution distribution_type;
+
+ explicit param_type(RealType a = 0,
+ RealType b = 1);
+
+ result_type a() const;
+ result_type b() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit uniform_real_distribution(RealType a = 0.0, RealType b = 1.0); // before C++20
+ uniform_real_distribution() : uniform_real_distribution(0.0) {} // C++20
+ explicit uniform_real_distribution(RealType a, RealType b = 1.0); // C++20
+ explicit uniform_real_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type a() const;
+ result_type b() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const uniform_real_distribution& x,
+ const uniform_real_distribution& y);
+ friend bool operator!=(const uniform_real_distribution& x,
+ const uniform_real_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const uniform_real_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ uniform_real_distribution& x);
+};
+
+class bernoulli_distribution
+{
+public:
+ // types
+ typedef bool result_type;
+
+ class param_type
+ {
+ public:
+ typedef bernoulli_distribution distribution_type;
+
+ explicit param_type(double p = 0.5);
+
+ double p() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit bernoulli_distribution(double p = 0.5); // before C++20
+ bernoulli_distribution() : bernoulli_distribution(0.5) {} // C++20
+ explicit bernoulli_distribution(double p); // C++20
+ explicit bernoulli_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ double p() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const bernoulli_distribution& x,
+ const bernoulli_distribution& y);
+ friend bool operator!=(const bernoulli_distribution& x,
+ const bernoulli_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const bernoulli_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ bernoulli_distribution& x);
+};
+
+template<class IntType = int>
+class binomial_distribution
+{
+public:
+ // types
+ typedef IntType result_type;
+
+ class param_type
+ {
+ public:
+ typedef binomial_distribution distribution_type;
+
+ explicit param_type(IntType t = 1, double p = 0.5);
+
+ IntType t() const;
+ double p() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit binomial_distribution(IntType t = 1, double p = 0.5); // before C++20
+ binomial_distribution() : binomial_distribution(1) {} // C++20
+ explicit binomial_distribution(IntType t, double p = 0.5); // C++20
+ explicit binomial_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ IntType t() const;
+ double p() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const binomial_distribution& x,
+ const binomial_distribution& y);
+ friend bool operator!=(const binomial_distribution& x,
+ const binomial_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const binomial_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ binomial_distribution& x);
+};
+
+template<class IntType = int>
+class geometric_distribution
+{
+public:
+ // types
+ typedef IntType result_type;
+
+ class param_type
+ {
+ public:
+ typedef geometric_distribution distribution_type;
+
+ explicit param_type(double p = 0.5);
+
+ double p() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit geometric_distribution(double p = 0.5); // before C++20
+ geometric_distribution() : geometric_distribution(0.5) {} // C++20
+ explicit geometric_distribution(double p); // C++20
+ explicit geometric_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ double p() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const geometric_distribution& x,
+ const geometric_distribution& y);
+ friend bool operator!=(const geometric_distribution& x,
+ const geometric_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const geometric_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ geometric_distribution& x);
+};
+
+template<class IntType = int>
+class negative_binomial_distribution
+{
+public:
+ // types
+ typedef IntType result_type;
+
+ class param_type
+ {
+ public:
+ typedef negative_binomial_distribution distribution_type;
+
+ explicit param_type(result_type k = 1, double p = 0.5);
+
+ result_type k() const;
+ double p() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit negative_binomial_distribution(IntType k = 1, double p = 0.5); // before C++20
+ negative_binomial_distribution() : negative_binomial_distribution(1) {} // C++20
+ explicit negative_binomial_distribution(IntType k, double p = 0.5); // C++20
+ explicit negative_binomial_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type k() const;
+ double p() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const negative_binomial_distribution& x,
+ const negative_binomial_distribution& y);
+ friend bool operator!=(const negative_binomial_distribution& x,
+ const negative_binomial_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const negative_binomial_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ negative_binomial_distribution& x);
+};
+
+template<class IntType = int>
+class poisson_distribution
+{
+public:
+ // types
+ typedef IntType result_type;
+
+ class param_type
+ {
+ public:
+ typedef poisson_distribution distribution_type;
+
+ explicit param_type(double mean = 1.0);
+
+ double mean() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit poisson_distribution(double mean = 1.0); // before C++20
+ poisson_distribution() : poisson_distribution(1.0) {} // C++20
+ explicit poisson_distribution(double mean); // C++20
+ explicit poisson_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ double mean() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const poisson_distribution& x,
+ const poisson_distribution& y);
+ friend bool operator!=(const poisson_distribution& x,
+ const poisson_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const poisson_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ poisson_distribution& x);
+};
+
+template<class RealType = double>
+class exponential_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef exponential_distribution distribution_type;
+
+ explicit param_type(result_type lambda = 1.0);
+
+ result_type lambda() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit exponential_distribution(RealType lambda = 1.0); // before C++20
+ exponential_distribution() : exponential_distribution(1.0) {} // C++20
+ explicit exponential_distribution(RealType lambda); // C++20
+ explicit exponential_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type lambda() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const exponential_distribution& x,
+ const exponential_distribution& y);
+ friend bool operator!=(const exponential_distribution& x,
+ const exponential_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const exponential_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ exponential_distribution& x);
+};
+
+template<class RealType = double>
+class gamma_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef gamma_distribution distribution_type;
+
+ explicit param_type(result_type alpha = 1, result_type beta = 1);
+
+ result_type alpha() const;
+ result_type beta() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit gamma_distribution(RealType alpha = 0.0, RealType beta = 1.0); // before C++20
+ gamma_distribution() : gamma_distribution(0.0) {} // C++20
+ explicit gamma_distribution(RealType alpha, RealType beta = 1.0); // C++20
+ explicit gamma_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type alpha() const;
+ result_type beta() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const gamma_distribution& x,
+ const gamma_distribution& y);
+ friend bool operator!=(const gamma_distribution& x,
+ const gamma_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const gamma_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ gamma_distribution& x);
+};
+
+template<class RealType = double>
+class weibull_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef weibull_distribution distribution_type;
+
+ explicit param_type(result_type alpha = 1, result_type beta = 1);
+
+ result_type a() const;
+ result_type b() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit weibull_distribution(RealType a = 1.0, RealType b = 1.0); // before C++20
+ weibull_distribution() : weibull_distribution(1.0) {} // C++20
+ explicit weibull_distribution(RealType a, RealType b = 1.0); // C++20
+ explicit weibull_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type a() const;
+ result_type b() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const weibull_distribution& x,
+ const weibull_distribution& y);
+ friend bool operator!=(const weibull_distribution& x,
+ const weibull_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const weibull_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ weibull_distribution& x);
+};
+
+template<class RealType = double>
+class extreme_value_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef extreme_value_distribution distribution_type;
+
+ explicit param_type(result_type a = 0, result_type b = 1);
+
+ result_type a() const;
+ result_type b() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit extreme_value_distribution(RealType a = 0.0, RealType b = 1.0); // before C++20
+ extreme_value_distribution() : extreme_value_distribution(0.0) {} // C++20
+ explicit extreme_value_distribution(RealType a, RealType b = 1.0); // C++20
+ explicit extreme_value_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type a() const;
+ result_type b() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const extreme_value_distribution& x,
+ const extreme_value_distribution& y);
+ friend bool operator!=(const extreme_value_distribution& x,
+ const extreme_value_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const extreme_value_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ extreme_value_distribution& x);
+};
+
+template<class RealType = double>
+class normal_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef normal_distribution distribution_type;
+
+ explicit param_type(result_type mean = 0, result_type stddev = 1);
+
+ result_type mean() const;
+ result_type stddev() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructors and reset functions
+ explicit normal_distribution(RealType mean = 0.0, RealType stddev = 1.0); // before C++20
+ normal_distribution() : normal_distribution(0.0) {} // C++20
+ explicit normal_distribution(RealType mean, RealType stddev = 1.0); // C++20
+ explicit normal_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type mean() const;
+ result_type stddev() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const normal_distribution& x,
+ const normal_distribution& y);
+ friend bool operator!=(const normal_distribution& x,
+ const normal_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const normal_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ normal_distribution& x);
+};
+
+template<class RealType = double>
+class lognormal_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef lognormal_distribution distribution_type;
+
+ explicit param_type(result_type m = 0, result_type s = 1);
+
+ result_type m() const;
+ result_type s() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit lognormal_distribution(RealType mean = 0.0, RealType stddev = 1.0); // before C++20
+ lognormal_distribution() : lognormal_distribution(0.0) {} // C++20
+ explicit lognormal_distribution(RealType mean, RealType stddev = 1.0); // C++20
+ explicit lognormal_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type m() const;
+ result_type s() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const lognormal_distribution& x,
+ const lognormal_distribution& y);
+ friend bool operator!=(const lognormal_distribution& x,
+ const lognormal_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const lognormal_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ lognormal_distribution& x);
+};
+
+template<class RealType = double>
+class chi_squared_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef chi_squared_distribution distribution_type;
+
+ explicit param_type(result_type n = 1);
+
+ result_type n() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit chi_squared_distribution(RealType n = 1.0); // before C++20
+ chi_squared_distribution() : chi_squared_distribution(1.0) {} // C++20
+ explicit chi_squared_distribution(RealType n); // C++20
+ explicit chi_squared_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type n() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const chi_squared_distribution& x,
+ const chi_squared_distribution& y);
+ friend bool operator!=(const chi_squared_distribution& x,
+ const chi_squared_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const chi_squared_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ chi_squared_distribution& x);
+};
+
+template<class RealType = double>
+class cauchy_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef cauchy_distribution distribution_type;
+
+ explicit param_type(result_type a = 0, result_type b = 1);
+
+ result_type a() const;
+ result_type b() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit cauchy_distribution(RealType a = 0.0, RealType b = 1.0); // before C++20
+ cauchy_distribution() : cauchy_distribution(0.0) {} // C++20
+ explicit cauchy_distribution(RealType a, RealType b = 1.0); // C++20
+ explicit cauchy_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type a() const;
+ result_type b() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const cauchy_distribution& x,
+ const cauchy_distribution& y);
+ friend bool operator!=(const cauchy_distribution& x,
+ const cauchy_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const cauchy_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ cauchy_distribution& x);
+};
+
+template<class RealType = double>
+class fisher_f_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef fisher_f_distribution distribution_type;
+
+ explicit param_type(result_type m = 1, result_type n = 1);
+
+ result_type m() const;
+ result_type n() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit fisher_f_distribution(RealType m = 1.0, RealType n = 1.0); // before C++20
+ fisher_f_distribution() : fisher_f_distribution(1.0) {} // C++20
+ explicit fisher_f_distribution(RealType m, RealType n = 1.0); // C++20
+ explicit fisher_f_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type m() const;
+ result_type n() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const fisher_f_distribution& x,
+ const fisher_f_distribution& y);
+ friend bool operator!=(const fisher_f_distribution& x,
+ const fisher_f_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const fisher_f_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ fisher_f_distribution& x);
+};
+
+template<class RealType = double>
+class student_t_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef student_t_distribution distribution_type;
+
+ explicit param_type(result_type n = 1);
+
+ result_type n() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit student_t_distribution(RealType n = 1.0); // before C++20
+ student_t_distribution() : student_t_distribution(1.0) {} // C++20
+ explicit student_t_distribution(RealType n); // C++20
+ explicit student_t_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type n() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const student_t_distribution& x,
+ const student_t_distribution& y);
+ friend bool operator!=(const student_t_distribution& x,
+ const student_t_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const student_t_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ student_t_distribution& x);
+};
+
+template<class IntType = int>
+class discrete_distribution
+{
+public:
+ // types
+ typedef IntType result_type;
+
+ class param_type
+ {
+ public:
+ typedef discrete_distribution distribution_type;
+
+ param_type();
+ template<class InputIterator>
+ param_type(InputIterator firstW, InputIterator lastW);
+ param_type(initializer_list<double> wl);
+ template<class UnaryOperation>
+ param_type(size_t nw, double xmin, double xmax, UnaryOperation fw);
+
+ vector<double> probabilities() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ discrete_distribution();
+ template<class InputIterator>
+ discrete_distribution(InputIterator firstW, InputIterator lastW);
+ discrete_distribution(initializer_list<double> wl);
+ template<class UnaryOperation>
+ discrete_distribution(size_t nw, double xmin, double xmax,
+ UnaryOperation fw);
+ explicit discrete_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ vector<double> probabilities() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const discrete_distribution& x,
+ const discrete_distribution& y);
+ friend bool operator!=(const discrete_distribution& x,
+ const discrete_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const discrete_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ discrete_distribution& x);
+};
+
+template<class RealType = double>
+class piecewise_constant_distribution
+{
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef piecewise_constant_distribution distribution_type;
+
+ param_type();
+ template<class InputIteratorB, class InputIteratorW>
+ param_type(InputIteratorB firstB, InputIteratorB lastB,
+ InputIteratorW firstW);
+ template<class UnaryOperation>
+ param_type(initializer_list<result_type> bl, UnaryOperation fw);
+ template<class UnaryOperation>
+ param_type(size_t nw, result_type xmin, result_type xmax,
+ UnaryOperation fw);
+
+ vector<result_type> intervals() const;
+ vector<result_type> densities() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ piecewise_constant_distribution();
+ template<class InputIteratorB, class InputIteratorW>
+ piecewise_constant_distribution(InputIteratorB firstB,
+ InputIteratorB lastB,
+ InputIteratorW firstW);
+ template<class UnaryOperation>
+ piecewise_constant_distribution(initializer_list<result_type> bl,
+ UnaryOperation fw);
+ template<class UnaryOperation>
+ piecewise_constant_distribution(size_t nw, result_type xmin,
+ result_type xmax, UnaryOperation fw);
+ explicit piecewise_constant_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ vector<result_type> intervals() const;
+ vector<result_type> densities() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const piecewise_constant_distribution& x,
+ const piecewise_constant_distribution& y);
+ friend bool operator!=(const piecewise_constant_distribution& x,
+ const piecewise_constant_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const piecewise_constant_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ piecewise_constant_distribution& x);
+};
+
+template<class RealType = double>
+class piecewise_linear_distribution
+{
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef piecewise_linear_distribution distribution_type;
+
+ param_type();
+ template<class InputIteratorB, class InputIteratorW>
+ param_type(InputIteratorB firstB, InputIteratorB lastB,
+ InputIteratorW firstW);
+ template<class UnaryOperation>
+ param_type(initializer_list<result_type> bl, UnaryOperation fw);
+ template<class UnaryOperation>
+ param_type(size_t nw, result_type xmin, result_type xmax,
+ UnaryOperation fw);
+
+ vector<result_type> intervals() const;
+ vector<result_type> densities() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ piecewise_linear_distribution();
+ template<class InputIteratorB, class InputIteratorW>
+ piecewise_linear_distribution(InputIteratorB firstB,
+ InputIteratorB lastB,
+ InputIteratorW firstW);
+
+ template<class UnaryOperation>
+ piecewise_linear_distribution(initializer_list<result_type> bl,
+ UnaryOperation fw);
+
+ template<class UnaryOperation>
+ piecewise_linear_distribution(size_t nw, result_type xmin,
+ result_type xmax, UnaryOperation fw);
+
+ explicit piecewise_linear_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ vector<result_type> intervals() const;
+ vector<result_type> densities() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const piecewise_linear_distribution& x,
+ const piecewise_linear_distribution& y);
+ friend bool operator!=(const piecewise_linear_distribution& x,
+ const piecewise_linear_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const piecewise_linear_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ piecewise_linear_distribution& x);
+};
+
+} // std
+*/
+
+#include <__config>
+#include <__random/bernoulli_distribution.h>
+#include <__random/binomial_distribution.h>
+#include <__random/cauchy_distribution.h>
+#include <__random/chi_squared_distribution.h>
+#include <__random/default_random_engine.h>
+#include <__random/discard_block_engine.h>
+#include <__random/discrete_distribution.h>
+#include <__random/exponential_distribution.h>
+#include <__random/extreme_value_distribution.h>
+#include <__random/fisher_f_distribution.h>
+#include <__random/gamma_distribution.h>
+#include <__random/generate_canonical.h>
+#include <__random/geometric_distribution.h>
+#include <__random/independent_bits_engine.h>
+#include <__random/is_seed_sequence.h>
+#include <__random/knuth_b.h>
+#include <__random/linear_congruential_engine.h>
+#include <__random/lognormal_distribution.h>
+#include <__random/mersenne_twister_engine.h>
+#include <__random/negative_binomial_distribution.h>
+#include <__random/normal_distribution.h>
+#include <__random/piecewise_constant_distribution.h>
+#include <__random/piecewise_linear_distribution.h>
+#include <__random/poisson_distribution.h>
+#include <__random/random_device.h>
+#include <__random/ranlux.h>
+#include <__random/seed_seq.h>
+#include <__random/shuffle_order_engine.h>
+#include <__random/student_t_distribution.h>
+#include <__random/subtract_with_carry_engine.h>
+#include <__random/uniform_int_distribution.h>
+#include <__random/uniform_random_bit_generator.h>
+#include <__random/uniform_real_distribution.h>
+#include <__random/weibull_distribution.h>
+#include <version>
+
+// standard-mandated includes
+
+// [rand.synopsis]
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <climits>
+# include <cmath>
+# include <concepts>
+# include <cstddef>
+# include <cstdint>
+# include <cstdlib>
+# include <iosfwd>
+# include <limits>
+# include <numeric>
+# include <string>
+# include <type_traits>
+# include <vector>
+#endif
+
+#endif // _LIBCPP_RANDOM
diff --git a/libcxx/include/__cxx03/ranges b/libcxx/include/__cxx03/ranges
new file mode 100644
index 00000000000000..fa35874265de67
--- /dev/null
+++ b/libcxx/include/__cxx03/ranges
@@ -0,0 +1,463 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_RANGES
+#define _LIBCPP_RANGES
+
+/*
+
+#include <compare> // see [compare.syn]
+#include <initializer_list> // see [initializer.list.syn]
+#include <iterator> // see [iterator.synopsis]
+
+namespace std::ranges {
+ inline namespace unspecified {
+ // [range.access], range access
+ inline constexpr unspecified begin = unspecified;
+ inline constexpr unspecified end = unspecified;
+ inline constexpr unspecified cbegin = unspecified;
+ inline constexpr unspecified cend = unspecified;
+
+ inline constexpr unspecified size = unspecified;
+ inline constexpr unspecified ssize = unspecified;
+ }
+
+ // [range.range], ranges
+ template<class T>
+ concept range = see below;
+
+ template<class T>
+ inline constexpr bool enable_borrowed_range = false;
+
+ template<class T>
+ using iterator_t = decltype(ranges::begin(declval<T&>()));
+ template<range R>
+ using sentinel_t = decltype(ranges::end(declval<R&>()));
+ template<range R>
+ using range_difference_t = iter_difference_t<iterator_t<R>>;
+ template<sized_range R>
+ using range_size_t = decltype(ranges::size(declval<R&>()));
+ template<range R>
+ using range_value_t = iter_value_t<iterator_t<R>>;
+ template<range R>
+ using range_reference_t = iter_reference_t<iterator_t<R>>;
+ template<range R>
+ using range_rvalue_reference_t = iter_rvalue_reference_t<iterator_t<R>>;
+ template <range R>
+ using range_common_reference_t = iter_common_reference_t<iterator_t<R>>;
+
+ // [range.sized], sized ranges
+ template<class>
+ inline constexpr bool disable_sized_range = false;
+
+ template<class T>
+ concept sized_range = ...;
+
+ // [range.view], views
+ template<class T>
+ inline constexpr bool enable_view = ...;
+
+ struct view_base { };
+
+ template<class T>
+ concept view = ...;
+
+ // [range.refinements], other range refinements
+ template<class R, class T>
+ concept output_range = see below;
+
+ template<class T>
+ concept input_range = see below;
+
+ template<class T>
+ concept forward_range = see below;
+
+ template<class T>
+ concept bidirectional_range = see below;
+
+ template<class T>
+ concept random_access_range = see below;
+
+ template<class T>
+ concept contiguous_range = see below;
+
+ template <class _Tp>
+ concept common_range = see below;
+
+ template<class T>
+ concept viewable_range = see below;
+
+ // [range.adaptor.object], range adaptor objects
+ template<class D>
+ requires is_class_v<D> && same_as<D, remove_cv_t<D>>
+ class range_adaptor_closure { }; // Since c++23
+
+ // [view.interface], class template view_interface
+ template<class D>
+ requires is_class_v<D> && same_as<D, remove_cv_t<D>>
+ class view_interface;
+
+ // [range.subrange], sub-ranges
+ enum class subrange_kind : bool { unsized, sized };
+
+ template<input_or_output_iterator I, sentinel_for<I> S = I, subrange_kind K = see below>
+ requires (K == subrange_kind::sized || !sized_sentinel_for<S, I>)
+ class subrange;
+
+ template<class I, class S, subrange_kind K>
+ inline constexpr bool enable_borrowed_range<subrange<I, S, K>> = true;
+
+ // [range.dangling], dangling iterator handling
+ struct dangling;
+
+ template<range R>
+ using borrowed_iterator_t = see below;
+
+ template<range R>
+ using borrowed_subrange_t = see below;
+
+ // [range.elements], elements view
+ template<input_range V, size_t N>
+ requires see below
+ class elements_view;
+
+ template<class T, size_t N>
+ inline constexpr bool enable_borrowed_range<elements_view<T, N>> =
+ enable_borrowed_range<T>;
+
+ template<class R>
+ using keys_view = elements_view<R, 0>;
+ template<class R>
+ using values_view = elements_view<R, 1>;
+
+ namespace views {
+ template<size_t N>
+ inline constexpr unspecified elements = unspecified;
+ inline constexpr auto keys = elements<0>;
+ inline constexpr auto values = elements<1>;
+ }
+
+ // [range.utility.conv], range conversions
+ template<class C, input_range R, class... Args> requires (!view<C>)
+ constexpr C to(R&& r, Args&&... args); // Since C++23
+ template<template<class...> class C, input_range R, class... Args>
+ constexpr auto to(R&& r, Args&&... args); // Since C++23
+ template<class C, class... Args> requires (!view<C>)
+ constexpr auto to(Args&&... args); // Since C++23
+ template<template<class...> class C, class... Args>
+ constexpr auto to(Args&&... args); // Since C++23
+
+ // [range.empty], empty view
+ template<class T>
+ requires is_object_v<T>
+ class empty_view;
+
+ template<class T>
+ inline constexpr bool enable_borrowed_range<empty_view<T>> = true;
+
+ namespace views {
+ template<class T>
+ inline constexpr empty_view<T> empty{};
+ }
+
+ // [range.all], all view
+ namespace views {
+ inline constexpr unspecified all = unspecified;
+
+ template<viewable_range R>
+ using all_t = decltype(all(declval<R>()));
+ }
+
+ template<range R>
+ requires is_object_v<R>
+ class ref_view;
+
+ template<class T>
+ inline constexpr bool enable_borrowed_range<ref_view<T>> = true;
+
+ template<range R>
+ requires see below
+ class owning_view;
+
+ template<class T>
+ inline constexpr bool enable_borrowed_range<owning_view<T>> = enable_borrowed_range<T>;
+
+ // [range.filter], filter view
+ template<input_range V, indirect_unary_predicate<iterator_t<V>> Pred>
+ requires view<V> && is_object_v<Pred>
+ class filter_view;
+
+ namespace views {
+ inline constexpr unspecified filter = unspecified;
+ }
+
+ // [range.drop], drop view
+ template<view V>
+ class drop_view;
+
+ template<class T>
+ inline constexpr bool enable_borrowed_range<drop_view<T>> = enable_borrowed_range<T>;
+
+ // [range.drop.while], drop while view
+ template<view V, class Pred>
+ requires input_range<V> && is_object_v<Pred> &&
+ indirect_unary_predicate<const Pred, iterator_t<V>>
+ class drop_while_view;
+
+ template<class T, class Pred>
+ inline constexpr bool enable_borrowed_range<drop_while_view<T, Pred>> =
+ enable_borrowed_range<T>;
+
+ namespace views { inline constexpr unspecified drop_while = unspecified; }
+
+ // [range.transform], transform view
+ template<input_range V, copy_constructible F>
+ requires view<V> && is_object_v<F> &&
+ regular_invocable<F&, range_reference_t<V>> &&
+ can-reference<invoke_result_t<F&, range_reference_t<V>>>
+ class transform_view;
+
+ // [range.counted], counted view
+ namespace views { inline constexpr unspecified counted = unspecified; }
+
+ // [range.common], common view
+ template<view V>
+ requires (!common_range<V> && copyable<iterator_t<V>>)
+ class common_view;
+
+ // [range.reverse], reverse view
+ template<view V>
+ requires bidirectional_range<V>
+ class reverse_view;
+
+ template<class T>
+ inline constexpr bool enable_borrowed_range<reverse_view<T>> = enable_borrowed_range<T>;
+
+ template<class T>
+ inline constexpr bool enable_borrowed_range<common_view<T>> = enable_borrowed_range<T>;
+
+ // [range.take], take view
+ template<view> class take_view;
+
+ template<class T>
+ inline constexpr bool enable_borrowed_range<take_view<T>> = enable_borrowed_range<T>;
+
+ // [range.take.while], take while view
+ template<view V, class Pred>
+ requires input_range<V> && is_object_v<Pred> &&
+ indirect_unary_predicate<const Pred, iterator_t<V>>
+ class take_while_view;
+
+ namespace views { inline constexpr unspecified take_while = unspecified; }
+
+ template<copy_constructible T>
+ requires is_object_v<T>
+ class single_view;
+
+ template<weakly_incrementable W, semiregular Bound = unreachable_sentinel_t>
+ requires weakly-equality-comparable-with<W, Bound> && copyable<W>
+ class iota_view;
+
+ template<class W, class Bound>
+ inline constexpr bool enable_borrowed_range<iota_view<W, Bound>> = true;
+
+ // [range.repeat], repeat view
+ template<class T>
+ concept integer-like-with-usable-difference-type = // exposition only
+ is-signed-integer-like<T> || (is-integer-like<T> && weakly_incrementable<T>);
+
+ template<move_constructible T, semiregular Bound = unreachable_sentinel_t>
+ requires (is_object_v<T> && same_as<T, remove_cv_t<T>> &&
+ (integer-like-with-usable-difference-type<Bound> ||
+ same_as<Bound, unreachable_sentinel_t>))
+ class repeat_view;
+
+ namespace views { inline constexpr unspecified repeat = unspecified; }
+
+ // [range.join], join view
+ template<input_range V>
+ requires view<V> && input_range<range_reference_t<V>>
+ class join_view;
+
+ // [range.lazy.split], lazy split view
+ template<class R>
+ concept tiny-range = see below; // exposition only
+
+ template<input_range V, forward_range Pattern>
+ requires view<V> && view<Pattern> &&
+ indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to> &&
+ (forward_range<V> || tiny-range<Pattern>)
+ class lazy_split_view;
+
+ // [range.split], split view
+ template<forward_range V, forward_range Pattern>
+ requires view<V> && view<Pattern> &&
+ indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
+ class split_view;
+
+ namespace views {
+ inline constexpr unspecified lazy_split = unspecified;
+ inline constexpr unspecified split = unspecified;
+ }
+
+ // [range.istream], istream view
+ template<movable Val, class CharT, class Traits = char_traits<CharT>>
+ requires see below
+ class basic_istream_view;
+
+ template<class Val>
+ using istream_view = basic_istream_view<Val, char>;
+
+ template<class Val>
+ using wistream_view = basic_istream_view<Val, wchar_t>;
+
+ namespace views { template<class T> inline constexpr unspecified istream = unspecified; }
+
+ // [range.zip], zip view
+ template<input_range... Views>
+ requires (view<Views> && ...) && (sizeof...(Views) > 0)
+ class zip_view; // C++23
+
+ template<class... Views>
+ inline constexpr bool enable_borrowed_range<zip_view<Views...>> = // C++23
+ (enable_borrowed_range<Views> && ...);
+
+ namespace views { inline constexpr unspecified zip = unspecified; } // C++23
+
+ // [range.as.rvalue]
+ template <view V>
+ requires input_range<V>
+ class as_rvalue_view; // C++23
+
+ namespace views { inline constexpr unspecified as_rvalue ) unspecified; } // C++23
+
+ [range.chunk.by]
+ template<forward_range V, indirect_binary_predicate<iterator_t<V>, iterator_t<V>> Pred>
+ requires view<V> && is_object_v<Pred>
+ class chunk_by_view; // C++23
+
+ namespace views { inline constexpr unspecified chunk_by = unspecified; } // C++23
+}
+
+namespace std {
+ namespace views = ranges::views;
+
+ template<class T> struct tuple_size;
+ template<size_t I, class T> struct tuple_element;
+
+ template<class I, class S, ranges::subrange_kind K>
+ struct tuple_size<ranges::subrange<I, S, K>>
+ : integral_constant<size_t, 2> {};
+
+ template<class I, class S, ranges::subrange_kind K>
+ struct tuple_element<0, ranges::subrange<I, S, K>> {
+ using type = I;
+ };
+
+ template<class I, class S, ranges::subrange_kind K>
+ struct tuple_element<1, ranges::subrange<I, S, K>> {
+ using type = S;
+ };
+
+ template<class I, class S, ranges::subrange_kind K>
+ struct tuple_element<0, const ranges::subrange<I, S, K>> {
+ using type = I;
+ };
+
+ template<class I, class S, ranges::subrange_kind K>
+ struct tuple_element<1, const ranges::subrange<I, S, K>> {
+ using type = S;
+ };
+
+ struct from_range_t { explicit from_range_t() = default; }; // Since C++23
+ inline constexpr from_range_t from_range{}; // Since C++23
+}
+*/
+
+#include <__config>
+
+#if _LIBCPP_STD_VER >= 20
+# include <__ranges/access.h>
+# include <__ranges/all.h>
+# include <__ranges/common_view.h>
+# include <__ranges/concepts.h>
+# include <__ranges/counted.h>
+# include <__ranges/dangling.h>
+# include <__ranges/data.h>
+# include <__ranges/drop_view.h>
+# include <__ranges/drop_while_view.h>
+# include <__ranges/elements_view.h>
+# include <__ranges/empty.h>
+# include <__ranges/empty_view.h>
+# include <__ranges/enable_borrowed_range.h>
+# include <__ranges/enable_view.h>
+# include <__ranges/filter_view.h>
+# include <__ranges/iota_view.h>
+# include <__ranges/join_view.h>
+# include <__ranges/lazy_split_view.h>
+# include <__ranges/rbegin.h>
+# include <__ranges/ref_view.h>
+# include <__ranges/rend.h>
+# include <__ranges/reverse_view.h>
+# include <__ranges/single_view.h>
+# include <__ranges/size.h>
+# include <__ranges/split_view.h>
+# include <__ranges/subrange.h>
+# include <__ranges/take_view.h>
+# include <__ranges/take_while_view.h>
+# include <__ranges/transform_view.h>
+# include <__ranges/view_interface.h>
+# include <__ranges/views.h>
+
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <__ranges/istream_view.h>
+# endif
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+# include <__ranges/as_rvalue_view.h>
+# include <__ranges/chunk_by_view.h>
+# include <__ranges/from_range.h>
+# include <__ranges/repeat_view.h>
+# include <__ranges/to.h>
+# include <__ranges/zip_view.h>
+#endif
+
+#include <version>
+
+// standard-mandated includes
+
+// [ranges.syn]
+#include <compare>
+#include <initializer_list>
+#include <iterator>
+
+// [tuple.helper]
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_size.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <cstddef>
+# include <limits>
+# include <optional>
+# include <span>
+# include <tuple>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdlib>
+# include <iosfwd>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_RANGES
diff --git a/libcxx/include/__cxx03/ratio b/libcxx/include/__cxx03/ratio
new file mode 100644
index 00000000000000..b989c272aaee6a
--- /dev/null
+++ b/libcxx/include/__cxx03/ratio
@@ -0,0 +1,517 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_RATIO
+#define _LIBCPP_RATIO
+
+/*
+ ratio synopsis
+
+namespace std
+{
+
+template <intmax_t N, intmax_t D = 1>
+class ratio
+{
+public:
+ static constexpr intmax_t num;
+ static constexpr intmax_t den;
+ typedef ratio<num, den> type;
+};
+
+// ratio arithmetic
+template <class R1, class R2> using ratio_add = ...;
+template <class R1, class R2> using ratio_subtract = ...;
+template <class R1, class R2> using ratio_multiply = ...;
+template <class R1, class R2> using ratio_divide = ...;
+
+// ratio comparison
+template <class R1, class R2> struct ratio_equal;
+template <class R1, class R2> struct ratio_not_equal;
+template <class R1, class R2> struct ratio_less;
+template <class R1, class R2> struct ratio_less_equal;
+template <class R1, class R2> struct ratio_greater;
+template <class R1, class R2> struct ratio_greater_equal;
+
+// convenience SI typedefs
+using quecto = ratio <1, 1'000'000'000'000'000'000'000'000'000'000>; // Since C++26; not supported
+using ronto = ratio <1, 1'000'000'000'000'000'000'000'000'000>; // Since C++26; not supported
+typedef ratio<1, 1000000000000000000000000> yocto; // not supported
+typedef ratio<1, 1000000000000000000000> zepto; // not supported
+typedef ratio<1, 1000000000000000000> atto;
+typedef ratio<1, 1000000000000000> femto;
+typedef ratio<1, 1000000000000> pico;
+typedef ratio<1, 1000000000> nano;
+typedef ratio<1, 1000000> micro;
+typedef ratio<1, 1000> milli;
+typedef ratio<1, 100> centi;
+typedef ratio<1, 10> deci;
+typedef ratio< 10, 1> deca;
+typedef ratio< 100, 1> hecto;
+typedef ratio< 1000, 1> kilo;
+typedef ratio< 1000000, 1> mega;
+typedef ratio< 1000000000, 1> giga;
+typedef ratio< 1000000000000, 1> tera;
+typedef ratio< 1000000000000000, 1> peta;
+typedef ratio< 1000000000000000000, 1> exa;
+typedef ratio< 1000000000000000000000, 1> zetta; // not supported
+typedef ratio<1000000000000000000000000, 1> yotta; // not supported
+using ronna = ratio <1'000'000'000'000'000'000'000'000'000, 1>; // Since C++26; not supported
+using quetta = ratio <1'000'000'000'000'000'000'000'000'000'000, 1>; // Since C++26; not supported
+
+ // 20.11.5, ratio comparison
+ template <class R1, class R2> inline constexpr bool ratio_equal_v
+ = ratio_equal<R1, R2>::value; // C++17
+ template <class R1, class R2> inline constexpr bool ratio_not_equal_v
+ = ratio_not_equal<R1, R2>::value; // C++17
+ template <class R1, class R2> inline constexpr bool ratio_less_v
+ = ratio_less<R1, R2>::value; // C++17
+ template <class R1, class R2> inline constexpr bool ratio_less_equal_v
+ = ratio_less_equal<R1, R2>::value; // C++17
+ template <class R1, class R2> inline constexpr bool ratio_greater_v
+ = ratio_greater<R1, R2>::value; // C++17
+ template <class R1, class R2> inline constexpr bool ratio_greater_equal_v
+ = ratio_greater_equal<R1, R2>::value; // C++17
+}
+*/
+
+#include <__config>
+#include <__type_traits/integral_constant.h>
+#include <climits>
+#include <cstdint>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// __static_gcd
+
+template <intmax_t _Xp, intmax_t _Yp>
+struct __static_gcd {
+ static const intmax_t value = __static_gcd<_Yp, _Xp % _Yp>::value;
+};
+
+template <intmax_t _Xp>
+struct __static_gcd<_Xp, 0> {
+ static const intmax_t value = _Xp;
+};
+
+template <>
+struct __static_gcd<0, 0> {
+ static const intmax_t value = 1;
+};
+
+// __static_lcm
+
+template <intmax_t _Xp, intmax_t _Yp>
+struct __static_lcm {
+ static const intmax_t value = _Xp / __static_gcd<_Xp, _Yp>::value * _Yp;
+};
+
+template <intmax_t _Xp>
+struct __static_abs {
+ static const intmax_t value = _Xp < 0 ? -_Xp : _Xp;
+};
+
+template <intmax_t _Xp>
+struct __static_sign {
+ static const intmax_t value = _Xp == 0 ? 0 : (_Xp < 0 ? -1 : 1);
+};
+
+template <intmax_t _Xp, intmax_t _Yp, intmax_t = __static_sign<_Yp>::value>
+class __ll_add;
+
+template <intmax_t _Xp, intmax_t _Yp>
+class __ll_add<_Xp, _Yp, 1> {
+ static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
+ static const intmax_t max = -min;
+
+ static_assert(_Xp <= max - _Yp, "overflow in __ll_add");
+
+public:
+ static const intmax_t value = _Xp + _Yp;
+};
+
+template <intmax_t _Xp, intmax_t _Yp>
+class __ll_add<_Xp, _Yp, 0> {
+public:
+ static const intmax_t value = _Xp;
+};
+
+template <intmax_t _Xp, intmax_t _Yp>
+class __ll_add<_Xp, _Yp, -1> {
+ static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
+ static const intmax_t max = -min;
+
+ static_assert(min - _Yp <= _Xp, "overflow in __ll_add");
+
+public:
+ static const intmax_t value = _Xp + _Yp;
+};
+
+template <intmax_t _Xp, intmax_t _Yp, intmax_t = __static_sign<_Yp>::value>
+class __ll_sub;
+
+template <intmax_t _Xp, intmax_t _Yp>
+class __ll_sub<_Xp, _Yp, 1> {
+ static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
+ static const intmax_t max = -min;
+
+ static_assert(min + _Yp <= _Xp, "overflow in __ll_sub");
+
+public:
+ static const intmax_t value = _Xp - _Yp;
+};
+
+template <intmax_t _Xp, intmax_t _Yp>
+class __ll_sub<_Xp, _Yp, 0> {
+public:
+ static const intmax_t value = _Xp;
+};
+
+template <intmax_t _Xp, intmax_t _Yp>
+class __ll_sub<_Xp, _Yp, -1> {
+ static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
+ static const intmax_t max = -min;
+
+ static_assert(_Xp <= max + _Yp, "overflow in __ll_sub");
+
+public:
+ static const intmax_t value = _Xp - _Yp;
+};
+
+template <intmax_t _Xp, intmax_t _Yp>
+class __ll_mul {
+ static const intmax_t nan = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1));
+ static const intmax_t min = nan + 1;
+ static const intmax_t max = -min;
+ static const intmax_t __a_x = __static_abs<_Xp>::value;
+ static const intmax_t __a_y = __static_abs<_Yp>::value;
+
+ static_assert(_Xp != nan && _Yp != nan && __a_x <= max / __a_y, "overflow in __ll_mul");
+
+public:
+ static const intmax_t value = _Xp * _Yp;
+};
+
+template <intmax_t _Yp>
+class __ll_mul<0, _Yp> {
+public:
+ static const intmax_t value = 0;
+};
+
+template <intmax_t _Xp>
+class __ll_mul<_Xp, 0> {
+public:
+ static const intmax_t value = 0;
+};
+
+template <>
+class __ll_mul<0, 0> {
+public:
+ static const intmax_t value = 0;
+};
+
+// Not actually used but left here in case needed in future maintenance
+template <intmax_t _Xp, intmax_t _Yp>
+class __ll_div {
+ static const intmax_t nan = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1));
+ static const intmax_t min = nan + 1;
+ static const intmax_t max = -min;
+
+ static_assert(_Xp != nan && _Yp != nan && _Yp != 0, "overflow in __ll_div");
+
+public:
+ static const intmax_t value = _Xp / _Yp;
+};
+
+template <intmax_t _Num, intmax_t _Den = 1>
+class _LIBCPP_TEMPLATE_VIS ratio {
+ static_assert(__static_abs<_Num>::value >= 0, "ratio numerator is out of range");
+ static_assert(_Den != 0, "ratio divide by 0");
+ static_assert(__static_abs<_Den>::value > 0, "ratio denominator is out of range");
+ static _LIBCPP_CONSTEXPR const intmax_t __na = __static_abs<_Num>::value;
+ static _LIBCPP_CONSTEXPR const intmax_t __da = __static_abs<_Den>::value;
+ static _LIBCPP_CONSTEXPR const intmax_t __s = __static_sign<_Num>::value * __static_sign<_Den>::value;
+ static _LIBCPP_CONSTEXPR const intmax_t __gcd = __static_gcd<__na, __da>::value;
+
+public:
+ static _LIBCPP_CONSTEXPR const intmax_t num = __s * __na / __gcd;
+ static _LIBCPP_CONSTEXPR const intmax_t den = __da / __gcd;
+
+ typedef ratio<num, den> type;
+};
+
+template <intmax_t _Num, intmax_t _Den>
+_LIBCPP_CONSTEXPR const intmax_t ratio<_Num, _Den>::num;
+
+template <intmax_t _Num, intmax_t _Den>
+_LIBCPP_CONSTEXPR const intmax_t ratio<_Num, _Den>::den;
+
+template <class _Tp>
+struct __is_ratio : false_type {};
+template <intmax_t _Num, intmax_t _Den>
+struct __is_ratio<ratio<_Num, _Den> > : true_type {};
+
+typedef ratio<1LL, 1000000000000000000LL> atto;
+typedef ratio<1LL, 1000000000000000LL> femto;
+typedef ratio<1LL, 1000000000000LL> pico;
+typedef ratio<1LL, 1000000000LL> nano;
+typedef ratio<1LL, 1000000LL> micro;
+typedef ratio<1LL, 1000LL> milli;
+typedef ratio<1LL, 100LL> centi;
+typedef ratio<1LL, 10LL> deci;
+typedef ratio< 10LL, 1LL> deca;
+typedef ratio< 100LL, 1LL> hecto;
+typedef ratio< 1000LL, 1LL> kilo;
+typedef ratio< 1000000LL, 1LL> mega;
+typedef ratio< 1000000000LL, 1LL> giga;
+typedef ratio< 1000000000000LL, 1LL> tera;
+typedef ratio< 1000000000000000LL, 1LL> peta;
+typedef ratio<1000000000000000000LL, 1LL> exa;
+
+template <class _R1, class _R2>
+struct __ratio_multiply {
+private:
+ static const intmax_t __gcd_n1_d2 = __static_gcd<_R1::num, _R2::den>::value;
+ static const intmax_t __gcd_d1_n2 = __static_gcd<_R1::den, _R2::num>::value;
+
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+
+public:
+ typedef typename ratio< __ll_mul<_R1::num / __gcd_n1_d2, _R2::num / __gcd_d1_n2>::value,
+ __ll_mul<_R2::den / __gcd_n1_d2, _R1::den / __gcd_d1_n2>::value >::type type;
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+using ratio_multiply = typename __ratio_multiply<_R1, _R2>::type;
+
+#else // _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_multiply : public __ratio_multiply<_R1, _R2>::type {};
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+struct __ratio_divide {
+private:
+ static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
+ static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
+
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+
+public:
+ typedef typename ratio< __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value,
+ __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value >::type type;
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+using ratio_divide = typename __ratio_divide<_R1, _R2>::type;
+
+#else // _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_divide : public __ratio_divide<_R1, _R2>::type {};
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+struct __ratio_add {
+private:
+ static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
+ static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
+
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+
+public:
+ typedef typename ratio_multiply<
+ ratio<__gcd_n1_n2, _R1::den / __gcd_d1_d2>,
+ ratio< __ll_add< __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value,
+ __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value >::value,
+ _R2::den > >::type type;
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+using ratio_add = typename __ratio_add<_R1, _R2>::type;
+
+#else // _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_add : public __ratio_add<_R1, _R2>::type {};
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+struct __ratio_subtract {
+private:
+ static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
+ static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
+
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+
+public:
+ typedef typename ratio_multiply<
+ ratio<__gcd_n1_n2, _R1::den / __gcd_d1_d2>,
+ ratio< __ll_sub< __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value,
+ __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value >::value,
+ _R2::den > >::type type;
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+using ratio_subtract = typename __ratio_subtract<_R1, _R2>::type;
+
+#else // _LIBCPP_CXX03_LANG
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_subtract : public __ratio_subtract<_R1, _R2>::type {};
+
+#endif // _LIBCPP_CXX03_LANG
+
+// ratio_equal
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_equal : _BoolConstant<(_R1::num == _R2::num && _R1::den == _R2::den)> {
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+};
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_not_equal : _BoolConstant<!ratio_equal<_R1, _R2>::value> {
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+};
+
+// ratio_less
+
+template <class _R1,
+ class _R2,
+ bool _Odd = false,
+ intmax_t _Q1 = _R1::num / _R1::den,
+ intmax_t _M1 = _R1::num % _R1::den,
+ intmax_t _Q2 = _R2::num / _R2::den,
+ intmax_t _M2 = _R2::num % _R2::den>
+struct __ratio_less1 {
+ static const bool value = _Odd ? _Q2 < _Q1 : _Q1 < _Q2;
+};
+
+template <class _R1, class _R2, bool _Odd, intmax_t _Qp>
+struct __ratio_less1<_R1, _R2, _Odd, _Qp, 0, _Qp, 0> {
+ static const bool value = false;
+};
+
+template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M2>
+struct __ratio_less1<_R1, _R2, _Odd, _Qp, 0, _Qp, _M2> {
+ static const bool value = !_Odd;
+};
+
+template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M1>
+struct __ratio_less1<_R1, _R2, _Odd, _Qp, _M1, _Qp, 0> {
+ static const bool value = _Odd;
+};
+
+template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M1, intmax_t _M2>
+struct __ratio_less1<_R1, _R2, _Odd, _Qp, _M1, _Qp, _M2> {
+ static const bool value = __ratio_less1<ratio<_R1::den, _M1>, ratio<_R2::den, _M2>, !_Odd>::value;
+};
+
+template <class _R1,
+ class _R2,
+ intmax_t _S1 = __static_sign<_R1::num>::value,
+ intmax_t _S2 = __static_sign<_R2::num>::value>
+struct __ratio_less {
+ static const bool value = _S1 < _S2;
+};
+
+template <class _R1, class _R2>
+struct __ratio_less<_R1, _R2, 1LL, 1LL> {
+ static const bool value = __ratio_less1<_R1, _R2>::value;
+};
+
+template <class _R1, class _R2>
+struct __ratio_less<_R1, _R2, -1LL, -1LL> {
+ static const bool value = __ratio_less1<ratio<-_R2::num, _R2::den>, ratio<-_R1::num, _R1::den> >::value;
+};
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_less : _BoolConstant<__ratio_less<_R1, _R2>::value> {
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+};
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_less_equal : _BoolConstant<!ratio_less<_R2, _R1>::value> {
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+};
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_greater : _BoolConstant<ratio_less<_R2, _R1>::value> {
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+};
+
+template <class _R1, class _R2>
+struct _LIBCPP_TEMPLATE_VIS ratio_greater_equal : _BoolConstant<!ratio_less<_R1, _R2>::value> {
+ static_assert(__is_ratio<_R1>::value, "[ratio.general]/2 requires R1 to be a specialisation of the ratio template");
+ static_assert(__is_ratio<_R2>::value, "[ratio.general]/2 requires R2 to be a specialisation of the ratio template");
+};
+
+template <class _R1, class _R2>
+struct __ratio_gcd {
+ typedef ratio<__static_gcd<_R1::num, _R2::num>::value, __static_lcm<_R1::den, _R2::den>::value> type;
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _R1, class _R2>
+inline constexpr bool ratio_equal_v = ratio_equal<_R1, _R2>::value;
+
+template <class _R1, class _R2>
+inline constexpr bool ratio_not_equal_v = ratio_not_equal<_R1, _R2>::value;
+
+template <class _R1, class _R2>
+inline constexpr bool ratio_less_v = ratio_less<_R1, _R2>::value;
+
+template <class _R1, class _R2>
+inline constexpr bool ratio_less_equal_v = ratio_less_equal<_R1, _R2>::value;
+
+template <class _R1, class _R2>
+inline constexpr bool ratio_greater_v = ratio_greater<_R1, _R2>::value;
+
+template <class _R1, class _R2>
+inline constexpr bool ratio_greater_equal_v = ratio_greater_equal<_R1, _R2>::value;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_RATIO
diff --git a/libcxx/include/__cxx03/regex b/libcxx/include/__cxx03/regex
new file mode 100644
index 00000000000000..b8141351213212
--- /dev/null
+++ b/libcxx/include/__cxx03/regex
@@ -0,0 +1,5836 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_REGEX
+#define _LIBCPP_REGEX
+
+/*
+ regex synopsis
+
+#include <compare>
+#include <initializer_list>
+
+namespace std
+{
+
+namespace regex_constants
+{
+
+enum syntax_option_type
+{
+ icase = unspecified,
+ nosubs = unspecified,
+ optimize = unspecified,
+ collate = unspecified,
+ ECMAScript = unspecified,
+ basic = unspecified,
+ extended = unspecified,
+ awk = unspecified,
+ grep = unspecified,
+ egrep = unspecified,
+ multiline = unspecified
+};
+
+constexpr syntax_option_type operator~(syntax_option_type f);
+constexpr syntax_option_type operator&(syntax_option_type lhs, syntax_option_type rhs);
+constexpr syntax_option_type operator|(syntax_option_type lhs, syntax_option_type rhs);
+
+enum match_flag_type
+{
+ match_default = 0,
+ match_not_bol = unspecified,
+ match_not_eol = unspecified,
+ match_not_bow = unspecified,
+ match_not_eow = unspecified,
+ match_any = unspecified,
+ match_not_null = unspecified,
+ match_continuous = unspecified,
+ match_prev_avail = unspecified,
+ format_default = 0,
+ format_sed = unspecified,
+ format_no_copy = unspecified,
+ format_first_only = unspecified
+};
+
+constexpr match_flag_type operator~(match_flag_type f);
+constexpr match_flag_type operator&(match_flag_type lhs, match_flag_type rhs);
+constexpr match_flag_type operator|(match_flag_type lhs, match_flag_type rhs);
+
+enum error_type
+{
+ error_collate = unspecified,
+ error_ctype = unspecified,
+ error_escape = unspecified,
+ error_backref = unspecified,
+ error_brack = unspecified,
+ error_paren = unspecified,
+ error_brace = unspecified,
+ error_badbrace = unspecified,
+ error_range = unspecified,
+ error_space = unspecified,
+ error_badrepeat = unspecified,
+ error_complexity = unspecified,
+ error_stack = unspecified
+};
+
+} // regex_constants
+
+class regex_error
+ : public runtime_error
+{
+public:
+ explicit regex_error(regex_constants::error_type ecode);
+ regex_constants::error_type code() const;
+};
+
+template <class charT>
+struct regex_traits
+{
+public:
+ typedef charT char_type;
+ typedef basic_string<char_type> string_type;
+ typedef locale locale_type;
+ typedef /bitmask_type/ char_class_type;
+
+ regex_traits();
+
+ static size_t length(const char_type* p);
+ charT translate(charT c) const;
+ charT translate_nocase(charT c) const;
+ template <class ForwardIterator>
+ string_type
+ transform(ForwardIterator first, ForwardIterator last) const;
+ template <class ForwardIterator>
+ string_type
+ transform_primary( ForwardIterator first, ForwardIterator last) const;
+ template <class ForwardIterator>
+ string_type
+ lookup_collatename(ForwardIterator first, ForwardIterator last) const;
+ template <class ForwardIterator>
+ char_class_type
+ lookup_classname(ForwardIterator first, ForwardIterator last,
+ bool icase = false) const;
+ bool isctype(charT c, char_class_type f) const;
+ int value(charT ch, int radix) const;
+ locale_type imbue(locale_type l);
+ locale_type getloc()const;
+};
+
+template <class charT, class traits = regex_traits<charT>>
+class basic_regex
+{
+public:
+ // types:
+ typedef charT value_type;
+ typedef traits traits_type;
+ typedef typename traits::string_type string_type;
+ typedef regex_constants::syntax_option_type flag_type;
+ typedef typename traits::locale_type locale_type;
+
+ // constants:
+ static constexpr regex_constants::syntax_option_type icase = regex_constants::icase;
+ static constexpr regex_constants::syntax_option_type nosubs = regex_constants::nosubs;
+ static constexpr regex_constants::syntax_option_type optimize = regex_constants::optimize;
+ static constexpr regex_constants::syntax_option_type collate = regex_constants::collate;
+ static constexpr regex_constants::syntax_option_type ECMAScript = regex_constants::ECMAScript;
+ static constexpr regex_constants::syntax_option_type basic = regex_constants::basic;
+ static constexpr regex_constants::syntax_option_type extended = regex_constants::extended;
+ static constexpr regex_constants::syntax_option_type awk = regex_constants::awk;
+ static constexpr regex_constants::syntax_option_type grep = regex_constants::grep;
+ static constexpr regex_constants::syntax_option_type egrep = regex_constants::egrep;
+ static constexpr regex_constants::syntax_option_type multiline = regex_constants::multiline;
+
+ // construct/copy/destroy:
+ basic_regex();
+ explicit basic_regex(const charT* p, flag_type f = regex_constants::ECMAScript);
+ basic_regex(const charT* p, size_t len, flag_type f = regex_constants::ECMAScript);
+ basic_regex(const basic_regex&);
+ basic_regex(basic_regex&&) noexcept;
+ template <class ST, class SA>
+ explicit basic_regex(const basic_string<charT, ST, SA>& p,
+ flag_type f = regex_constants::ECMAScript);
+ template <class ForwardIterator>
+ basic_regex(ForwardIterator first, ForwardIterator last,
+ flag_type f = regex_constants::ECMAScript);
+ basic_regex(initializer_list<charT>, flag_type = regex_constants::ECMAScript);
+
+ ~basic_regex();
+
+ basic_regex& operator=(const basic_regex&);
+ basic_regex& operator=(basic_regex&&) noexcept;
+ basic_regex& operator=(const charT* ptr);
+ basic_regex& operator=(initializer_list<charT> il);
+ template <class ST, class SA>
+ basic_regex& operator=(const basic_string<charT, ST, SA>& p);
+
+ // assign:
+ basic_regex& assign(const basic_regex& that);
+ basic_regex& assign(basic_regex&& that) noexcept;
+ basic_regex& assign(const charT* ptr, flag_type f = regex_constants::ECMAScript);
+ basic_regex& assign(const charT* p, size_t len, flag_type f = regex_constants::ECMAScript);
+ template <class string_traits, class A>
+ basic_regex& assign(const basic_string<charT, string_traits, A>& s,
+ flag_type f = regex_constants::ECMAScript);
+ template <class InputIterator>
+ basic_regex& assign(InputIterator first, InputIterator last,
+ flag_type f = regex_constants::ECMAScript);
+ basic_regex& assign(initializer_list<charT>, flag_type f = regex_constants::ECMAScript);
+
+ // const operations:
+ unsigned mark_count() const;
+ flag_type flags() const;
+
+ // locale:
+ locale_type imbue(locale_type loc);
+ locale_type getloc() const;
+
+ // swap:
+ void swap(basic_regex&);
+};
+
+template<class ForwardIterator>
+basic_regex(ForwardIterator, ForwardIterator,
+ regex_constants::syntax_option_type = regex_constants::ECMAScript)
+ -> basic_regex<typename iterator_traits<ForwardIterator>::value_type>; // C++17
+
+typedef basic_regex<char> regex;
+typedef basic_regex<wchar_t> wregex;
+
+template <class charT, class traits>
+ void swap(basic_regex<charT, traits>& e1, basic_regex<charT, traits>& e2);
+
+template <class BidirectionalIterator>
+class sub_match
+ : public pair<BidirectionalIterator, BidirectionalIterator>
+{
+public:
+ typedef typename iterator_traits<BidirectionalIterator>::value_type value_type;
+ typedef typename iterator_traits<BidirectionalIterator>::difference_type difference_type;
+ typedef BidirectionalIterator iterator;
+ typedef basic_string<value_type> string_type;
+
+ bool matched;
+
+ constexpr sub_match();
+
+ difference_type length() const;
+ operator string_type() const;
+ string_type str() const;
+
+ int compare(const sub_match& s) const;
+ int compare(const string_type& s) const;
+ int compare(const value_type* s) const;
+
+ void swap(sub_match& s) noexcept(see below);
+};
+
+typedef sub_match<const char*> csub_match;
+typedef sub_match<const wchar_t*> wcsub_match;
+typedef sub_match<string::const_iterator> ssub_match;
+typedef sub_match<wstring::const_iterator> wssub_match;
+
+template <class BiIter>
+ bool
+ operator==(const sub_match<BiIter>& lhs, const sub_match<BiIter>& rhs);
+
+template <class BiIter>
+ auto
+ operator<=>(const sub_match<BiIter>& lhs, const sub_match<BiIter>& rhs); // Since C++20
+
+ template <class BiIter> // Removed in C++20
+ bool
+ operator!=(const sub_match<BiIter>& lhs, const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<(const sub_match<BiIter>& lhs, const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<=(const sub_match<BiIter>& lhs, const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>=(const sub_match<BiIter>& lhs, const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>(const sub_match<BiIter>& lhs, const sub_match<BiIter>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator==(const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator!=(const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator<(const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator>(const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool operator>=(const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator<=(const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter, class ST, class SA>
+ bool
+ operator==(const sub_match<BiIter>& lhs,
+ const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& rhs);
+
+template <class BiIter, class ST, class SA> // Since C++20
+ auto
+ operator<=>(const sub_match<BiIter>& lhs,
+ const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator!=(const sub_match<BiIter>& lhs,
+ const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator<(const sub_match<BiIter>& lhs,
+ const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator>(const sub_match<BiIter>& lhs,
+ const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator>=(const sub_match<BiIter>& lhs,
+ const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator<=(const sub_match<BiIter>& lhs,
+ const basic_string<typename iterator_traits<BiIter>::value_type, ST, SA>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator==(typename iterator_traits<BiIter>::value_type const* lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator!=(typename iterator_traits<BiIter>::value_type const* lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<(typename iterator_traits<BiIter>::value_type const* lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>(typename iterator_traits<BiIter>::value_type const* lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>=(typename iterator_traits<BiIter>::value_type const* lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<=(typename iterator_traits<BiIter>::value_type const* lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter>
+ bool
+ operator==(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const* rhs);
+
+template <class BiIter> // Since C++20
+ auto
+ operator<=>(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const* rhs);
+
+template <class BiIter, class ST, class SA> // Removed in C++20
+ bool
+ operator!=(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const* rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const* rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const* rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>=(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const* rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<=(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const* rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator==(typename iterator_traits<BiIter>::value_type const& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator!=(typename iterator_traits<BiIter>::value_type const& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<(typename iterator_traits<BiIter>::value_type const& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>(typename iterator_traits<BiIter>::value_type const& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>=(typename iterator_traits<BiIter>::value_type const& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<=(typename iterator_traits<BiIter>::value_type const& lhs,
+ const sub_match<BiIter>& rhs);
+
+template <class BiIter>
+ bool
+ operator==(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const& rhs);
+
+template <class BiIter> // Since C++20
+ auto
+ operator<=>(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator!=(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator>=(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const& rhs);
+
+template <class BiIter> // Removed in C++20
+ bool
+ operator<=(const sub_match<BiIter>& lhs,
+ typename iterator_traits<BiIter>::value_type const& rhs);
+
+template <class charT, class ST, class BiIter>
+ basic_ostream<charT, ST>&
+ operator<<(basic_ostream<charT, ST>& os, const sub_match<BiIter>& m);
+
+template <class BidirectionalIterator,
+ class Allocator = allocator<sub_match<BidirectionalIterator>>>
+class match_results
+{
+public:
+ typedef sub_match<BidirectionalIterator> value_type;
+ typedef const value_type& const_reference;
+ typedef value_type& reference;
+ typedef /implementation-defined/ const_iterator;
+ typedef const_iterator iterator;
+ typedef typename iterator_traits<BidirectionalIterator>::difference_type difference_type;
+ typedef typename allocator_traits<Allocator>::size_type size_type;
+ typedef Allocator allocator_type;
+ typedef typename iterator_traits<BidirectionalIterator>::value_type char_type;
+ typedef basic_string<char_type> string_type;
+
+ // construct/copy/destroy:
+ explicit match_results(const Allocator& a = Allocator()); // before C++20
+ match_results() : match_results(Allocator()) {} // C++20
+ explicit match_results(const Allocator& a); // C++20
+ match_results(const match_results& m);
+ match_results(match_results&& m) noexcept;
+ match_results& operator=(const match_results& m);
+ match_results& operator=(match_results&& m);
+ ~match_results();
+
+ bool ready() const;
+
+ // size:
+ size_type size() const;
+ size_type max_size() const;
+ bool empty() const;
+
+ // element access:
+ difference_type length(size_type sub = 0) const;
+ difference_type position(size_type sub = 0) const;
+ string_type str(size_type sub = 0) const;
+ const_reference operator[](size_type n) const;
+
+ const_reference prefix() const;
+ const_reference suffix() const;
+
+ const_iterator begin() const;
+ const_iterator end() const;
+ const_iterator cbegin() const;
+ const_iterator cend() const;
+
+ // format:
+ template <class OutputIter>
+ OutputIter
+ format(OutputIter out, const char_type* fmt_first,
+ const char_type* fmt_last,
+ regex_constants::match_flag_type flags = regex_constants::format_default) const;
+ template <class OutputIter, class ST, class SA>
+ OutputIter
+ format(OutputIter out, const basic_string<char_type, ST, SA>& fmt,
+ regex_constants::match_flag_type flags = regex_constants::format_default) const;
+ template <class ST, class SA>
+ basic_string<char_type, ST, SA>
+ format(const basic_string<char_type, ST, SA>& fmt,
+ regex_constants::match_flag_type flags = regex_constants::format_default) const;
+ string_type
+ format(const char_type* fmt,
+ regex_constants::match_flag_type flags = regex_constants::format_default) const;
+
+ // allocator:
+ allocator_type get_allocator() const;
+
+ // swap:
+ void swap(match_results& that);
+};
+
+typedef match_results<const char*> cmatch;
+typedef match_results<const wchar_t*> wcmatch;
+typedef match_results<string::const_iterator> smatch;
+typedef match_results<wstring::const_iterator> wsmatch;
+
+template <class BidirectionalIterator, class Allocator>
+ bool
+ operator==(const match_results<BidirectionalIterator, Allocator>& m1,
+ const match_results<BidirectionalIterator, Allocator>& m2);
+
+template <class BidirectionalIterator, class Allocator> // Removed in C++20
+ bool
+ operator!=(const match_results<BidirectionalIterator, Allocator>& m1,
+ const match_results<BidirectionalIterator, Allocator>& m2);
+
+template <class BidirectionalIterator, class Allocator>
+ void
+ swap(match_results<BidirectionalIterator, Allocator>& m1,
+ match_results<BidirectionalIterator, Allocator>& m2);
+
+template <class BidirectionalIterator, class Allocator, class charT, class traits>
+ bool
+ regex_match(BidirectionalIterator first, BidirectionalIterator last,
+ match_results<BidirectionalIterator, Allocator>& m,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class BidirectionalIterator, class charT, class traits>
+ bool
+ regex_match(BidirectionalIterator first, BidirectionalIterator last,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class charT, class Allocator, class traits>
+ bool
+ regex_match(const charT* str, match_results<const charT*, Allocator>& m,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class ST, class SA, class Allocator, class charT, class traits>
+ bool
+ regex_match(const basic_string<charT, ST, SA>& s,
+ match_results<typename basic_string<charT, ST, SA>::const_iterator, Allocator>& m,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class ST, class SA, class Allocator, class charT, class traits>
+ bool
+ regex_match(const basic_string<charT, ST, SA>&& s,
+ match_results<typename basic_string<charT, ST, SA>::const_iterator, Allocator>& m,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default) = delete; // C++14
+
+template <class charT, class traits>
+ bool
+ regex_match(const charT* str, const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class ST, class SA, class charT, class traits>
+ bool
+ regex_match(const basic_string<charT, ST, SA>& s,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class BidirectionalIterator, class Allocator, class charT, class traits>
+ bool
+ regex_search(BidirectionalIterator first, BidirectionalIterator last,
+ match_results<BidirectionalIterator, Allocator>& m,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class BidirectionalIterator, class charT, class traits>
+ bool
+ regex_search(BidirectionalIterator first, BidirectionalIterator last,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class charT, class Allocator, class traits>
+ bool
+ regex_search(const charT* str, match_results<const charT*, Allocator>& m,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class charT, class traits>
+ bool
+ regex_search(const charT* str, const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class ST, class SA, class charT, class traits>
+ bool
+ regex_search(const basic_string<charT, ST, SA>& s,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class ST, class SA, class Allocator, class charT, class traits>
+ bool
+ regex_search(const basic_string<charT, ST, SA>& s,
+ match_results<typename basic_string<charT, ST, SA>::const_iterator, Allocator>& m,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class ST, class SA, class Allocator, class charT, class traits>
+ bool
+ regex_search(const basic_string<charT, ST, SA>&& s,
+ match_results<typename basic_string<charT, ST, SA>::const_iterator, Allocator>& m,
+ const basic_regex<charT, traits>& e,
+ regex_constants::match_flag_type flags = regex_constants::match_default) = delete; // C++14
+
+template <class OutputIterator, class BidirectionalIterator,
+ class traits, class charT, class ST, class SA>
+ OutputIterator
+ regex_replace(OutputIterator out,
+ BidirectionalIterator first, BidirectionalIterator last,
+ const basic_regex<charT, traits>& e,
+ const basic_string<charT, ST, SA>& fmt,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class OutputIterator, class BidirectionalIterator,
+ class traits, class charT>
+ OutputIterator
+ regex_replace(OutputIterator out,
+ BidirectionalIterator first, BidirectionalIterator last,
+ const basic_regex<charT, traits>& e, const charT* fmt,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class traits, class charT, class ST, class SA, class FST, class FSA>
+ basic_string<charT, ST, SA>
+ regex_replace(const basic_string<charT, ST, SA>& s,
+ const basic_regex<charT, traits>& e,
+ const basic_string<charT, FST, FSA>& fmt,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class traits, class charT, class ST, class SA>
+ basic_string<charT, ST, SA>
+ regex_replace(const basic_string<charT, ST, SA>& s,
+ const basic_regex<charT, traits>& e, const charT* fmt,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class traits, class charT, class ST, class SA>
+ basic_string<charT>
+ regex_replace(const charT* s,
+ const basic_regex<charT, traits>& e,
+ const basic_string<charT, ST, SA>& fmt,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class traits, class charT>
+ basic_string<charT>
+ regex_replace(const charT* s,
+ const basic_regex<charT, traits>& e,
+ const charT* fmt,
+ regex_constants::match_flag_type flags = regex_constants::match_default);
+
+template <class BidirectionalIterator,
+ class charT = typename iterator_traits< BidirectionalIterator>::value_type,
+ class traits = regex_traits<charT>>
+class regex_iterator
+{
+public:
+ typedef basic_regex<charT, traits> regex_type;
+ typedef match_results<BidirectionalIterator> value_type;
+ typedef ptrdiff_t difference_type;
+ typedef const value_type* pointer;
+ typedef const value_type& reference;
+ typedef forward_iterator_tag iterator_category;
+ typedef input_iterator_tag iterator_concept; // since C++20
+
+ regex_iterator();
+ regex_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type& re,
+ regex_constants::match_flag_type m = regex_constants::match_default);
+ regex_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type&& re,
+ regex_constants::match_flag_type m
+ = regex_constants::match_default) = delete; // C++14
+ regex_iterator(const regex_iterator&);
+ regex_iterator& operator=(const regex_iterator&);
+
+ bool operator==(const regex_iterator&) const;
+ bool operator==(default_sentinel_t) const { return *this == regex_iterator(); } // since C++20
+ bool operator!=(const regex_iterator&) const; // Removed in C++20
+
+ const value_type& operator*() const;
+ const value_type* operator->() const;
+
+ regex_iterator& operator++();
+ regex_iterator operator++(int);
+};
+
+typedef regex_iterator<const char*> cregex_iterator;
+typedef regex_iterator<const wchar_t*> wcregex_iterator;
+typedef regex_iterator<string::const_iterator> sregex_iterator;
+typedef regex_iterator<wstring::const_iterator> wsregex_iterator;
+
+template <class BidirectionalIterator,
+ class charT = typename iterator_traits<BidirectionalIterator>::value_type,
+ class traits = regex_traits<charT>>
+class regex_token_iterator
+{
+public:
+ typedef basic_regex<charT, traits> regex_type;
+ typedef sub_match<BidirectionalIterator> value_type;
+ typedef ptrdiff_t difference_type;
+ typedef const value_type* pointer;
+ typedef const value_type& reference;
+ typedef forward_iterator_tag iterator_category;
+ typedef input_iterator_tag iterator_concept; // since C++20
+
+ regex_token_iterator();
+ regex_token_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type& re, int submatch = 0,
+ regex_constants::match_flag_type m = regex_constants::match_default);
+ regex_token_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type&& re, int submatch = 0,
+ regex_constants::match_flag_type m = regex_constants::match_default) = delete; // C++14
+ regex_token_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type& re, const vector<int>& submatches,
+ regex_constants::match_flag_type m = regex_constants::match_default);
+ regex_token_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type&& re, const vector<int>& submatches,
+ regex_constants::match_flag_type m = regex_constants::match_default) = delete; // C++14
+ regex_token_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type& re, initializer_list<int> submatches,
+ regex_constants::match_flag_type m = regex_constants::match_default);
+ regex_token_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type&& re, initializer_list<int> submatches,
+ regex_constants::match_flag_type m = regex_constants::match_default) = delete; // C++14
+ template <size_t N>
+ regex_token_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type& re, const int (&submatches)[N],
+ regex_constants::match_flag_type m = regex_constants::match_default);
+ template <size_t N>
+ regex_token_iterator(BidirectionalIterator a, BidirectionalIterator b,
+ const regex_type&& re, const int (&submatches)[N],
+ regex_constants::match_flag_type m = regex_constants::match_default) = delete; // C++14
+ regex_token_iterator(const regex_token_iterator&);
+ regex_token_iterator& operator=(const regex_token_iterator&);
+
+ bool operator==(const regex_token_iterator&) const;
+ bool operator==(default_sentinel_t) const { return *this == regex_token_iterator(); } // since C++20
+ bool operator!=(const regex_token_iterator&) const; // Removed in C++20
+
+ const value_type& operator*() const;
+ const value_type* operator->() const;
+
+ regex_token_iterator& operator++();
+ regex_token_iterator operator++(int);
+};
+
+typedef regex_token_iterator<const char*> cregex_token_iterator;
+typedef regex_token_iterator<const wchar_t*> wcregex_token_iterator;
+typedef regex_token_iterator<string::const_iterator> sregex_token_iterator;
+typedef regex_token_iterator<wstring::const_iterator> wsregex_token_iterator;
+
+} // std
+*/
+
+#include <__algorithm/find.h>
+#include <__algorithm/search.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/default_sentinel.h>
+#include <__iterator/wrap_iter.h>
+#include <__locale>
+#include <__memory/shared_ptr.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__type_traits/is_swappable.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/swap.h>
+#include <__verbose_abort>
+#include <deque>
+#include <stdexcept>
+#include <string>
+#include <vector>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [re.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#define _LIBCPP_REGEX_COMPLEXITY_FACTOR 4096
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace regex_constants {
+
+// syntax_option_type
+
+enum syntax_option_type {
+ icase = 1 << 0,
+ nosubs = 1 << 1,
+ optimize = 1 << 2,
+ collate = 1 << 3,
+#ifdef _LIBCPP_ABI_REGEX_CONSTANTS_NONZERO
+ ECMAScript = 1 << 9,
+#else
+ ECMAScript = 0,
+#endif
+ basic = 1 << 4,
+ extended = 1 << 5,
+ awk = 1 << 6,
+ grep = 1 << 7,
+ egrep = 1 << 8,
+ // 1 << 9 may be used by ECMAScript
+ multiline = 1 << 10
+};
+
+_LIBCPP_HIDE_FROM_ABI inline _LIBCPP_CONSTEXPR syntax_option_type __get_grammar(syntax_option_type __g) {
+#ifdef _LIBCPP_ABI_REGEX_CONSTANTS_NONZERO
+ return static_cast<syntax_option_type>(__g & 0x3F0);
+#else
+ return static_cast<syntax_option_type>(__g & 0x1F0);
+#endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR syntax_option_type operator~(syntax_option_type __x) {
+ return syntax_option_type(~int(__x) & 0x1FF);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR syntax_option_type
+operator&(syntax_option_type __x, syntax_option_type __y) {
+ return syntax_option_type(int(__x) & int(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR syntax_option_type
+operator|(syntax_option_type __x, syntax_option_type __y) {
+ return syntax_option_type(int(__x) | int(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR syntax_option_type
+operator^(syntax_option_type __x, syntax_option_type __y) {
+ return syntax_option_type(int(__x) ^ int(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI syntax_option_type& operator&=(syntax_option_type& __x, syntax_option_type __y) {
+ __x = __x & __y;
+ return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI syntax_option_type& operator|=(syntax_option_type& __x, syntax_option_type __y) {
+ __x = __x | __y;
+ return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI syntax_option_type& operator^=(syntax_option_type& __x, syntax_option_type __y) {
+ __x = __x ^ __y;
+ return __x;
+}
+
+// match_flag_type
+
+enum match_flag_type {
+ match_default = 0,
+ match_not_bol = 1 << 0,
+ match_not_eol = 1 << 1,
+ match_not_bow = 1 << 2,
+ match_not_eow = 1 << 3,
+ match_any = 1 << 4,
+ match_not_null = 1 << 5,
+ match_continuous = 1 << 6,
+ match_prev_avail = 1 << 7,
+ format_default = 0,
+ format_sed = 1 << 8,
+ format_no_copy = 1 << 9,
+ format_first_only = 1 << 10,
+ __no_update_pos = 1 << 11,
+ __full_match = 1 << 12
+};
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR match_flag_type operator~(match_flag_type __x) {
+ return match_flag_type(~int(__x) & 0x0FFF);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR match_flag_type operator&(match_flag_type __x, match_flag_type __y) {
+ return match_flag_type(int(__x) & int(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR match_flag_type operator|(match_flag_type __x, match_flag_type __y) {
+ return match_flag_type(int(__x) | int(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR match_flag_type operator^(match_flag_type __x, match_flag_type __y) {
+ return match_flag_type(int(__x) ^ int(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI match_flag_type& operator&=(match_flag_type& __x, match_flag_type __y) {
+ __x = __x & __y;
+ return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI match_flag_type& operator|=(match_flag_type& __x, match_flag_type __y) {
+ __x = __x | __y;
+ return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI match_flag_type& operator^=(match_flag_type& __x, match_flag_type __y) {
+ __x = __x ^ __y;
+ return __x;
+}
+
+enum error_type {
+ error_collate = 1,
+ error_ctype,
+ error_escape,
+ error_backref,
+ error_brack,
+ error_paren,
+ error_brace,
+ error_badbrace,
+ error_range,
+ error_space,
+ error_badrepeat,
+ error_complexity,
+ error_stack,
+ __re_err_grammar,
+ __re_err_empty,
+ __re_err_unknown,
+ __re_err_parse
+};
+
+} // namespace regex_constants
+
+class _LIBCPP_EXPORTED_FROM_ABI regex_error : public runtime_error {
+ regex_constants::error_type __code_;
+
+public:
+ explicit regex_error(regex_constants::error_type __ecode);
+ _LIBCPP_HIDE_FROM_ABI regex_error(const regex_error&) _NOEXCEPT = default;
+ ~regex_error() _NOEXCEPT override;
+ _LIBCPP_HIDE_FROM_ABI regex_constants::error_type code() const { return __code_; }
+};
+
+template <regex_constants::error_type _Ev>
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_regex_error() {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw regex_error(_Ev);
+#else
+ _LIBCPP_VERBOSE_ABORT("regex_error was thrown in -fno-exceptions mode");
+#endif
+}
+
+template <class _CharT>
+struct _LIBCPP_TEMPLATE_VIS regex_traits {
+public:
+ typedef _CharT char_type;
+ typedef basic_string<char_type> string_type;
+ typedef locale locale_type;
+#if defined(__BIONIC__) || defined(_NEWLIB_VERSION)
+ // Originally bionic's ctype_base used its own ctype masks because the
+ // builtin ctype implementation wasn't in libc++ yet. Bionic's ctype mask
+ // was only 8 bits wide and already saturated, so it used a wider type here
+ // to make room for __regex_word (then a part of this class rather than
+ // ctype_base). Bionic has since moved to the builtin ctype_base
+ // implementation, but this was not updated to match. Since then Android has
+ // needed to maintain a stable libc++ ABI, and this can't be changed without
+ // an ABI break.
+ // We also need this workaround for newlib since _NEWLIB_VERSION is not
+ // defined yet inside __config, so we can't set the
+ // _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE macro. Additionally, newlib is
+ // often used for space constrained environments, so it makes sense not to
+ // duplicate the ctype table.
+ typedef uint16_t char_class_type;
+#else
+ typedef ctype_base::mask char_class_type;
+#endif
+
+ static const char_class_type __regex_word = ctype_base::__regex_word;
+
+private:
+ locale __loc_;
+ const ctype<char_type>* __ct_;
+ const collate<char_type>* __col_;
+
+public:
+ regex_traits();
+
+ _LIBCPP_HIDE_FROM_ABI static size_t length(const char_type* __p) { return char_traits<char_type>::length(__p); }
+ _LIBCPP_HIDE_FROM_ABI char_type translate(char_type __c) const { return __c; }
+ char_type translate_nocase(char_type __c) const;
+ template <class _ForwardIterator>
+ string_type transform(_ForwardIterator __f, _ForwardIterator __l) const;
+ template <class _ForwardIterator>
+ _LIBCPP_HIDE_FROM_ABI string_type transform_primary(_ForwardIterator __f, _ForwardIterator __l) const {
+ return __transform_primary(__f, __l, char_type());
+ }
+ template <class _ForwardIterator>
+ _LIBCPP_HIDE_FROM_ABI string_type lookup_collatename(_ForwardIterator __f, _ForwardIterator __l) const {
+ return __lookup_collatename(__f, __l, char_type());
+ }
+ template <class _ForwardIterator>
+ _LIBCPP_HIDE_FROM_ABI char_class_type
+ lookup_classname(_ForwardIterator __f, _ForwardIterator __l, bool __icase = false) const {
+ return __lookup_classname(__f, __l, __icase, char_type());
+ }
+ bool isctype(char_type __c, char_class_type __m) const;
+ _LIBCPP_HIDE_FROM_ABI int value(char_type __ch, int __radix) const { return __regex_traits_value(__ch, __radix); }
+ locale_type imbue(locale_type __l);
+ _LIBCPP_HIDE_FROM_ABI locale_type getloc() const { return __loc_; }
+
+private:
+ void __init();
+
+ template <class _ForwardIterator>
+ string_type __transform_primary(_ForwardIterator __f, _ForwardIterator __l, char) const;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ template <class _ForwardIterator>
+ string_type __transform_primary(_ForwardIterator __f, _ForwardIterator __l, wchar_t) const;
+#endif
+ template <class _ForwardIterator>
+ string_type __lookup_collatename(_ForwardIterator __f, _ForwardIterator __l, char) const;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ template <class _ForwardIterator>
+ string_type __lookup_collatename(_ForwardIterator __f, _ForwardIterator __l, wchar_t) const;
+#endif
+ template <class _ForwardIterator>
+ char_class_type __lookup_classname(_ForwardIterator __f, _ForwardIterator __l, bool __icase, char) const;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ template <class _ForwardIterator>
+ char_class_type __lookup_classname(_ForwardIterator __f, _ForwardIterator __l, bool __icase, wchar_t) const;
+#endif
+
+ static int __regex_traits_value(unsigned char __ch, int __radix);
+ _LIBCPP_HIDE_FROM_ABI int __regex_traits_value(char __ch, int __radix) const {
+ return __regex_traits_value(static_cast<unsigned char>(__ch), __radix);
+ }
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+ _LIBCPP_HIDE_FROM_ABI int __regex_traits_value(wchar_t __ch, int __radix) const;
+#endif
+};
+
+template <class _CharT>
+const typename regex_traits<_CharT>::char_class_type regex_traits<_CharT>::__regex_word;
+
+template <class _CharT>
+regex_traits<_CharT>::regex_traits() {
+ __init();
+}
+
+template <class _CharT>
+typename regex_traits<_CharT>::char_type regex_traits<_CharT>::translate_nocase(char_type __c) const {
+ return __ct_->tolower(__c);
+}
+
+template <class _CharT>
+template <class _ForwardIterator>
+typename regex_traits<_CharT>::string_type
+regex_traits<_CharT>::transform(_ForwardIterator __f, _ForwardIterator __l) const {
+ string_type __s(__f, __l);
+ return __col_->transform(__s.data(), __s.data() + __s.size());
+}
+
+template <class _CharT>
+void regex_traits<_CharT>::__init() {
+ __ct_ = &std::use_facet<ctype<char_type> >(__loc_);
+ __col_ = &std::use_facet<collate<char_type> >(__loc_);
+}
+
+template <class _CharT>
+typename regex_traits<_CharT>::locale_type regex_traits<_CharT>::imbue(locale_type __l) {
+ locale __r = __loc_;
+ __loc_ = __l;
+ __init();
+ return __r;
+}
+
+// transform_primary is very FreeBSD-specific
+
+template <class _CharT>
+template <class _ForwardIterator>
+typename regex_traits<_CharT>::string_type
+regex_traits<_CharT>::__transform_primary(_ForwardIterator __f, _ForwardIterator __l, char) const {
+ const string_type __s(__f, __l);
+ string_type __d = __col_->transform(__s.data(), __s.data() + __s.size());
+ switch (__d.size()) {
+ case 1:
+ break;
+ case 12:
+ __d[11] = __d[3];
+ break;
+ default:
+ __d.clear();
+ break;
+ }
+ return __d;
+}
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _CharT>
+template <class _ForwardIterator>
+typename regex_traits<_CharT>::string_type
+regex_traits<_CharT>::__transform_primary(_ForwardIterator __f, _ForwardIterator __l, wchar_t) const {
+ const string_type __s(__f, __l);
+ string_type __d = __col_->transform(__s.data(), __s.data() + __s.size());
+ switch (__d.size()) {
+ case 1:
+ break;
+ case 3:
+ __d[2] = __d[0];
+ break;
+ default:
+ __d.clear();
+ break;
+ }
+ return __d;
+}
+#endif
+
+// lookup_collatename is very FreeBSD-specific
+
+_LIBCPP_EXPORTED_FROM_ABI string __get_collation_name(const char* __s);
+
+template <class _CharT>
+template <class _ForwardIterator>
+typename regex_traits<_CharT>::string_type
+regex_traits<_CharT>::__lookup_collatename(_ForwardIterator __f, _ForwardIterator __l, char) const {
+ string_type __s(__f, __l);
+ string_type __r;
+ if (!__s.empty()) {
+ __r = std::__get_collation_name(__s.c_str());
+ if (__r.empty() && __s.size() <= 2) {
+ __r = __col_->transform(__s.data(), __s.data() + __s.size());
+ if (__r.size() == 1 || __r.size() == 12)
+ __r = __s;
+ else
+ __r.clear();
+ }
+ }
+ return __r;
+}
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _CharT>
+template <class _ForwardIterator>
+typename regex_traits<_CharT>::string_type
+regex_traits<_CharT>::__lookup_collatename(_ForwardIterator __f, _ForwardIterator __l, wchar_t) const {
+ string_type __s(__f, __l);
+ string __n;
+ __n.reserve(__s.size());
+ for (typename string_type::const_iterator __i = __s.begin(), __e = __s.end(); __i != __e; ++__i) {
+ if (static_cast<unsigned>(*__i) >= 127)
+ return string_type();
+ __n.push_back(char(*__i));
+ }
+ string_type __r;
+ if (!__s.empty()) {
+ __n = __get_collation_name(__n.c_str());
+ if (!__n.empty())
+ __r.assign(__n.begin(), __n.end());
+ else if (__s.size() <= 2) {
+ __r = __col_->transform(__s.data(), __s.data() + __s.size());
+ if (__r.size() == 1 || __r.size() == 3)
+ __r = __s;
+ else
+ __r.clear();
+ }
+ }
+ return __r;
+}
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+// lookup_classname
+
+regex_traits<char>::char_class_type _LIBCPP_EXPORTED_FROM_ABI __get_classname(const char* __s, bool __icase);
+
+template <class _CharT>
+template <class _ForwardIterator>
+typename regex_traits<_CharT>::char_class_type
+regex_traits<_CharT>::__lookup_classname(_ForwardIterator __f, _ForwardIterator __l, bool __icase, char) const {
+ string_type __s(__f, __l);
+ __ct_->tolower(&__s[0], &__s[0] + __s.size());
+ return std::__get_classname(__s.c_str(), __icase);
+}
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _CharT>
+template <class _ForwardIterator>
+typename regex_traits<_CharT>::char_class_type
+regex_traits<_CharT>::__lookup_classname(_ForwardIterator __f, _ForwardIterator __l, bool __icase, wchar_t) const {
+ string_type __s(__f, __l);
+ __ct_->tolower(&__s[0], &__s[0] + __s.size());
+ string __n;
+ __n.reserve(__s.size());
+ for (typename string_type::const_iterator __i = __s.begin(), __e = __s.end(); __i != __e; ++__i) {
+ if (static_cast<unsigned>(*__i) >= 127)
+ return char_class_type();
+ __n.push_back(char(*__i));
+ }
+ return __get_classname(__n.c_str(), __icase);
+}
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+template <class _CharT>
+bool regex_traits<_CharT>::isctype(char_type __c, char_class_type __m) const {
+ if (__ct_->is(__m, __c))
+ return true;
+ return (__c == '_' && (__m & __regex_word));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool __is_07(unsigned char __c) {
+ return (__c & 0xF8u) ==
+#if defined(__MVS__) && !defined(__NATIVE_ASCII_F)
+ 0xF0;
+#else
+ 0x30;
+#endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI bool __is_89(unsigned char __c) {
+ return (__c & 0xFEu) ==
+#if defined(__MVS__) && !defined(__NATIVE_ASCII_F)
+ 0xF8;
+#else
+ 0x38;
+#endif
+}
+
+inline _LIBCPP_HIDE_FROM_ABI unsigned char __to_lower(unsigned char __c) {
+#if defined(__MVS__) && !defined(__NATIVE_ASCII_F)
+ return __c & 0xBF;
+#else
+ return __c | 0x20;
+#endif
+}
+
+template <class _CharT>
+int regex_traits<_CharT>::__regex_traits_value(unsigned char __ch, int __radix) {
+ if (__is_07(__ch)) // '0' <= __ch && __ch <= '7'
+ return __ch - '0';
+ if (__radix != 8) {
+ if (__is_89(__ch)) // '8' <= __ch && __ch <= '9'
+ return __ch - '0';
+ if (__radix == 16) {
+ __ch = __to_lower(__ch); // tolower
+ if ('a' <= __ch && __ch <= 'f')
+ return __ch - ('a' - 10);
+ }
+ }
+ return -1;
+}
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _CharT>
+inline int regex_traits<_CharT>::__regex_traits_value(wchar_t __ch, int __radix) const {
+ return __regex_traits_value(static_cast<unsigned char>(__ct_->narrow(__ch, char_type())), __radix);
+}
+#endif
+
+template <class _CharT>
+class __node;
+
+template <class _BidirectionalIterator>
+class _LIBCPP_TEMPLATE_VIS sub_match;
+
+template <class _BidirectionalIterator, class _Allocator = allocator<sub_match<_BidirectionalIterator> > >
+class _LIBCPP_TEMPLATE_VIS match_results;
+
+template <class _CharT>
+struct __state {
+ enum {
+ __end_state = -1000,
+ __consume_input, // -999
+ __begin_marked_expr, // -998
+ __end_marked_expr, // -997
+ __pop_state, // -996
+ __accept_and_consume, // -995
+ __accept_but_not_consume, // -994
+ __reject, // -993
+ __split,
+ __repeat
+ };
+
+ int __do_;
+ const _CharT* __first_;
+ const _CharT* __current_;
+ const _CharT* __last_;
+ vector<sub_match<const _CharT*> > __sub_matches_;
+ vector<pair<size_t, const _CharT*> > __loop_data_;
+ const __node<_CharT>* __node_;
+ regex_constants::match_flag_type __flags_;
+ bool __at_first_;
+
+ _LIBCPP_HIDE_FROM_ABI __state()
+ : __do_(0),
+ __first_(nullptr),
+ __current_(nullptr),
+ __last_(nullptr),
+ __node_(nullptr),
+ __flags_(),
+ __at_first_(false) {}
+};
+
+// __node
+
+template <class _CharT>
+class __node {
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __node() {}
+ __node(const __node&) = delete;
+ __node& operator=(const __node&) = delete;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ virtual ~__node() {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ virtual void __exec(__state&) const {}
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ virtual void __exec_split(bool, __state&) const {}
+};
+
+// __end_state
+
+template <class _CharT>
+class __end_state : public __node<_CharT> {
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __end_state() {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __end_state<_CharT>::__exec(__state& __s) const {
+ __s.__do_ = __state::__end_state;
+}
+
+// __has_one_state
+
+template <class _CharT>
+class __has_one_state : public __node<_CharT> {
+ __node<_CharT>* __first_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __has_one_state(__node<_CharT>* __s) : __first_(__s) {}
+
+ _LIBCPP_HIDE_FROM_ABI __node<_CharT>* first() const { return __first_; }
+ _LIBCPP_HIDE_FROM_ABI __node<_CharT>*& first() { return __first_; }
+};
+
+// __owns_one_state
+
+template <class _CharT>
+class __owns_one_state : public __has_one_state<_CharT> {
+ typedef __has_one_state<_CharT> base;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __owns_one_state(__node<_CharT>* __s) : base(__s) {}
+
+ ~__owns_one_state() override;
+};
+
+template <class _CharT>
+__owns_one_state<_CharT>::~__owns_one_state() {
+ delete this->first();
+}
+
+// __empty_state
+
+template <class _CharT>
+class __empty_state : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __empty_state(__node<_CharT>* __s) : base(__s) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __empty_state<_CharT>::__exec(__state& __s) const {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+}
+
+// __empty_non_own_state
+
+template <class _CharT>
+class __empty_non_own_state : public __has_one_state<_CharT> {
+ typedef __has_one_state<_CharT> base;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __empty_non_own_state(__node<_CharT>* __s) : base(__s) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __empty_non_own_state<_CharT>::__exec(__state& __s) const {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+}
+
+// __repeat_one_loop
+
+template <class _CharT>
+class __repeat_one_loop : public __has_one_state<_CharT> {
+ typedef __has_one_state<_CharT> base;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __repeat_one_loop(__node<_CharT>* __s) : base(__s) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __repeat_one_loop<_CharT>::__exec(__state& __s) const {
+ __s.__do_ = __state::__repeat;
+ __s.__node_ = this->first();
+}
+
+// __owns_two_states
+
+template <class _CharT>
+class __owns_two_states : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ base* __second_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __owns_two_states(__node<_CharT>* __s1, base* __s2) : base(__s1), __second_(__s2) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual ~__owns_two_states();
+
+ _LIBCPP_HIDE_FROM_ABI base* second() const { return __second_; }
+ _LIBCPP_HIDE_FROM_ABI base*& second() { return __second_; }
+};
+
+template <class _CharT>
+__owns_two_states<_CharT>::~__owns_two_states() {
+ delete __second_;
+}
+
+// __loop
+
+template <class _CharT>
+class __loop : public __owns_two_states<_CharT> {
+ typedef __owns_two_states<_CharT> base;
+
+ size_t __min_;
+ size_t __max_;
+ unsigned __loop_id_;
+ unsigned __mexp_begin_;
+ unsigned __mexp_end_;
+ bool __greedy_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __loop(
+ unsigned __loop_id,
+ __node<_CharT>* __s1,
+ __owns_one_state<_CharT>* __s2,
+ unsigned __mexp_begin,
+ unsigned __mexp_end,
+ bool __greedy = true,
+ size_t __min = 0,
+ size_t __max = numeric_limits<size_t>::max())
+ : base(__s1, __s2),
+ __min_(__min),
+ __max_(__max),
+ __loop_id_(__loop_id),
+ __mexp_begin_(__mexp_begin),
+ __mexp_end_(__mexp_end),
+ __greedy_(__greedy) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state& __s) const;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec_split(bool __second, __state& __s) const;
+
+private:
+ _LIBCPP_HIDE_FROM_ABI void __init_repeat(__state& __s) const {
+ __s.__loop_data_[__loop_id_].second = __s.__current_;
+ for (size_t __i = __mexp_begin_ - 1; __i != __mexp_end_ - 1; ++__i) {
+ __s.__sub_matches_[__i].first = __s.__last_;
+ __s.__sub_matches_[__i].second = __s.__last_;
+ __s.__sub_matches_[__i].matched = false;
+ }
+ }
+};
+
+template <class _CharT>
+void __loop<_CharT>::__exec(__state& __s) const {
+ if (__s.__do_ == __state::__repeat) {
+ bool __do_repeat = ++__s.__loop_data_[__loop_id_].first < __max_;
+ bool __do_alt = __s.__loop_data_[__loop_id_].first >= __min_;
+ if (__do_repeat && __do_alt && __s.__loop_data_[__loop_id_].second == __s.__current_)
+ __do_repeat = false;
+ if (__do_repeat && __do_alt)
+ __s.__do_ = __state::__split;
+ else if (__do_repeat) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+ __init_repeat(__s);
+ } else {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->second();
+ }
+ } else {
+ __s.__loop_data_[__loop_id_].first = 0;
+ bool __do_repeat = 0 < __max_;
+ bool __do_alt = 0 >= __min_;
+ if (__do_repeat && __do_alt)
+ __s.__do_ = __state::__split;
+ else if (__do_repeat) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+ __init_repeat(__s);
+ } else {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->second();
+ }
+ }
+}
+
+template <class _CharT>
+void __loop<_CharT>::__exec_split(bool __second, __state& __s) const {
+ __s.__do_ = __state::__accept_but_not_consume;
+ if (__greedy_ != __second) {
+ __s.__node_ = this->first();
+ __init_repeat(__s);
+ } else
+ __s.__node_ = this->second();
+}
+
+// __alternate
+
+template <class _CharT>
+class __alternate : public __owns_two_states<_CharT> {
+ typedef __owns_two_states<_CharT> base;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __alternate(__owns_one_state<_CharT>* __s1, __owns_one_state<_CharT>* __s2)
+ : base(__s1, __s2) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state& __s) const;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec_split(bool __second, __state& __s) const;
+};
+
+template <class _CharT>
+void __alternate<_CharT>::__exec(__state& __s) const {
+ __s.__do_ = __state::__split;
+}
+
+template <class _CharT>
+void __alternate<_CharT>::__exec_split(bool __second, __state& __s) const {
+ __s.__do_ = __state::__accept_but_not_consume;
+ if (__second)
+ __s.__node_ = this->second();
+ else
+ __s.__node_ = this->first();
+}
+
+// __begin_marked_subexpression
+
+template <class _CharT>
+class __begin_marked_subexpression : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ unsigned __mexp_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __begin_marked_subexpression(unsigned __mexp, __node<_CharT>* __s)
+ : base(__s), __mexp_(__mexp) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __begin_marked_subexpression<_CharT>::__exec(__state& __s) const {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__sub_matches_[__mexp_ - 1].first = __s.__current_;
+ __s.__node_ = this->first();
+}
+
+// __end_marked_subexpression
+
+template <class _CharT>
+class __end_marked_subexpression : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ unsigned __mexp_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __end_marked_subexpression(unsigned __mexp, __node<_CharT>* __s)
+ : base(__s), __mexp_(__mexp) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __end_marked_subexpression<_CharT>::__exec(__state& __s) const {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__sub_matches_[__mexp_ - 1].second = __s.__current_;
+ __s.__sub_matches_[__mexp_ - 1].matched = true;
+ __s.__node_ = this->first();
+}
+
+// __back_ref
+
+template <class _CharT>
+class __back_ref : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ unsigned __mexp_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __back_ref(unsigned __mexp, __node<_CharT>* __s) : base(__s), __mexp_(__mexp) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __back_ref<_CharT>::__exec(__state& __s) const {
+ if (__mexp_ > __s.__sub_matches_.size())
+ __throw_regex_error<regex_constants::error_backref>();
+ sub_match<const _CharT*>& __sm = __s.__sub_matches_[__mexp_ - 1];
+ if (__sm.matched) {
+ ptrdiff_t __len = __sm.second - __sm.first;
+ if (__s.__last_ - __s.__current_ >= __len && std::equal(__sm.first, __sm.second, __s.__current_)) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__current_ += __len;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __back_ref_icase
+
+template <class _CharT, class _Traits>
+class __back_ref_icase : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ _Traits __traits_;
+ unsigned __mexp_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __back_ref_icase(const _Traits& __traits, unsigned __mexp, __node<_CharT>* __s)
+ : base(__s), __traits_(__traits), __mexp_(__mexp) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT, class _Traits>
+void __back_ref_icase<_CharT, _Traits>::__exec(__state& __s) const {
+ sub_match<const _CharT*>& __sm = __s.__sub_matches_[__mexp_ - 1];
+ if (__sm.matched) {
+ ptrdiff_t __len = __sm.second - __sm.first;
+ if (__s.__last_ - __s.__current_ >= __len) {
+ for (ptrdiff_t __i = 0; __i < __len; ++__i) {
+ if (__traits_.translate_nocase(__sm.first[__i]) != __traits_.translate_nocase(__s.__current_[__i]))
+ goto __not_equal;
+ }
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__current_ += __len;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+ } else {
+ __not_equal:
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __back_ref_collate
+
+template <class _CharT, class _Traits>
+class __back_ref_collate : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ _Traits __traits_;
+ unsigned __mexp_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __back_ref_collate(const _Traits& __traits, unsigned __mexp, __node<_CharT>* __s)
+ : base(__s), __traits_(__traits), __mexp_(__mexp) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT, class _Traits>
+void __back_ref_collate<_CharT, _Traits>::__exec(__state& __s) const {
+ sub_match<const _CharT*>& __sm = __s.__sub_matches_[__mexp_ - 1];
+ if (__sm.matched) {
+ ptrdiff_t __len = __sm.second - __sm.first;
+ if (__s.__last_ - __s.__current_ >= __len) {
+ for (ptrdiff_t __i = 0; __i < __len; ++__i) {
+ if (__traits_.translate(__sm.first[__i]) != __traits_.translate(__s.__current_[__i]))
+ goto __not_equal;
+ }
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__current_ += __len;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+ } else {
+ __not_equal:
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __word_boundary
+
+template <class _CharT, class _Traits>
+class __word_boundary : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ _Traits __traits_;
+ bool __invert_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __word_boundary(const _Traits& __traits, bool __invert, __node<_CharT>* __s)
+ : base(__s), __traits_(__traits), __invert_(__invert) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT, class _Traits>
+void __word_boundary<_CharT, _Traits>::__exec(__state& __s) const {
+ bool __is_word_b = false;
+ if (__s.__first_ != __s.__last_) {
+ if (__s.__current_ == __s.__last_) {
+ if (!(__s.__flags_ & regex_constants::match_not_eow)) {
+ _CharT __c = __s.__current_[-1];
+ __is_word_b = __c == '_' || __traits_.isctype(__c, ctype_base::alnum);
+ }
+ } else if (__s.__current_ == __s.__first_ && !(__s.__flags_ & regex_constants::match_prev_avail)) {
+ if (!(__s.__flags_ & regex_constants::match_not_bow)) {
+ _CharT __c = *__s.__current_;
+ __is_word_b = __c == '_' || __traits_.isctype(__c, ctype_base::alnum);
+ }
+ } else {
+ _CharT __c1 = __s.__current_[-1];
+ _CharT __c2 = *__s.__current_;
+ bool __is_c1_b = __c1 == '_' || __traits_.isctype(__c1, ctype_base::alnum);
+ bool __is_c2_b = __c2 == '_' || __traits_.isctype(__c2, ctype_base::alnum);
+ __is_word_b = __is_c1_b != __is_c2_b;
+ }
+ }
+ if (__is_word_b != __invert_) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __l_anchor
+
+template <class _CharT>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool __is_eol(_CharT __c) {
+ return __c == '\r' || __c == '\n';
+}
+
+template <class _CharT>
+class __l_anchor_multiline : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ bool __multiline_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __l_anchor_multiline(bool __multiline, __node<_CharT>* __s)
+ : base(__s), __multiline_(__multiline) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __l_anchor_multiline<_CharT>::__exec(__state& __s) const {
+ if (__s.__at_first_ && __s.__current_ == __s.__first_ && !(__s.__flags_ & regex_constants::match_not_bol)) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+ } else if (__multiline_ && !__s.__at_first_ && std::__is_eol(*std::prev(__s.__current_))) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __r_anchor
+
+template <class _CharT>
+class __r_anchor_multiline : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ bool __multiline_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __r_anchor_multiline(bool __multiline, __node<_CharT>* __s)
+ : base(__s), __multiline_(__multiline) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __r_anchor_multiline<_CharT>::__exec(__state& __s) const {
+ if (__s.__current_ == __s.__last_ && !(__s.__flags_ & regex_constants::match_not_eol)) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+ } else if (__multiline_ && std::__is_eol(*__s.__current_)) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __match_any
+
+template <class _CharT>
+class __match_any : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __match_any(__node<_CharT>* __s) : base(__s) {}
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __match_any<_CharT>::__exec(__state& __s) const {
+ if (__s.__current_ != __s.__last_ && *__s.__current_ != 0) {
+ __s.__do_ = __state::__accept_and_consume;
+ ++__s.__current_;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __match_any_but_newline
+
+template <class _CharT>
+class __match_any_but_newline : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __match_any_but_newline(__node<_CharT>* __s) : base(__s) {}
+
+ void __exec(__state&) const override;
+};
+
+template <>
+_LIBCPP_EXPORTED_FROM_ABI void __match_any_but_newline<char>::__exec(__state&) const;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+_LIBCPP_EXPORTED_FROM_ABI void __match_any_but_newline<wchar_t>::__exec(__state&) const;
+#endif
+
+// __match_char
+
+template <class _CharT>
+class __match_char : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ _CharT __c_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __match_char(_CharT __c, __node<_CharT>* __s) : base(__s), __c_(__c) {}
+
+ __match_char(const __match_char&) = delete;
+ __match_char& operator=(const __match_char&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT>
+void __match_char<_CharT>::__exec(__state& __s) const {
+ if (__s.__current_ != __s.__last_ && *__s.__current_ == __c_) {
+ __s.__do_ = __state::__accept_and_consume;
+ ++__s.__current_;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __match_char_icase
+
+template <class _CharT, class _Traits>
+class __match_char_icase : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ _Traits __traits_;
+ _CharT __c_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __match_char_icase(const _Traits& __traits, _CharT __c, __node<_CharT>* __s)
+ : base(__s), __traits_(__traits), __c_(__traits.translate_nocase(__c)) {}
+
+ __match_char_icase(const __match_char_icase&) = delete;
+ __match_char_icase& operator=(const __match_char_icase&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT, class _Traits>
+void __match_char_icase<_CharT, _Traits>::__exec(__state& __s) const {
+ if (__s.__current_ != __s.__last_ && __traits_.translate_nocase(*__s.__current_) == __c_) {
+ __s.__do_ = __state::__accept_and_consume;
+ ++__s.__current_;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __match_char_collate
+
+template <class _CharT, class _Traits>
+class __match_char_collate : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ _Traits __traits_;
+ _CharT __c_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI __match_char_collate(const _Traits& __traits, _CharT __c, __node<_CharT>* __s)
+ : base(__s), __traits_(__traits), __c_(__traits.translate(__c)) {}
+
+ __match_char_collate(const __match_char_collate&) = delete;
+ __match_char_collate& operator=(const __match_char_collate&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT, class _Traits>
+void __match_char_collate<_CharT, _Traits>::__exec(__state& __s) const {
+ if (__s.__current_ != __s.__last_ && __traits_.translate(*__s.__current_) == __c_) {
+ __s.__do_ = __state::__accept_and_consume;
+ ++__s.__current_;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+// __bracket_expression
+
+template <class _CharT, class _Traits>
+class __bracket_expression : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+ typedef typename _Traits::string_type string_type;
+
+ _Traits __traits_;
+ vector<_CharT> __chars_;
+ vector<_CharT> __neg_chars_;
+ vector<pair<string_type, string_type> > __ranges_;
+ vector<pair<_CharT, _CharT> > __digraphs_;
+ vector<string_type> __equivalences_;
+ typename regex_traits<_CharT>::char_class_type __mask_;
+ typename regex_traits<_CharT>::char_class_type __neg_mask_;
+ bool __negate_;
+ bool __icase_;
+ bool __collate_;
+ bool __might_have_digraph_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI
+ __bracket_expression(const _Traits& __traits, __node<_CharT>* __s, bool __negate, bool __icase, bool __collate)
+ : base(__s),
+ __traits_(__traits),
+ __mask_(),
+ __neg_mask_(),
+ __negate_(__negate),
+ __icase_(__icase),
+ __collate_(__collate),
+ __might_have_digraph_(__traits_.getloc().name() != "C") {}
+
+ __bracket_expression(const __bracket_expression&) = delete;
+ __bracket_expression& operator=(const __bracket_expression&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+
+ _LIBCPP_HIDE_FROM_ABI bool __negated() const { return __negate_; }
+
+ _LIBCPP_HIDE_FROM_ABI void __add_char(_CharT __c) {
+ if (__icase_)
+ __chars_.push_back(__traits_.translate_nocase(__c));
+ else if (__collate_)
+ __chars_.push_back(__traits_.translate(__c));
+ else
+ __chars_.push_back(__c);
+ }
+ _LIBCPP_HIDE_FROM_ABI void __add_neg_char(_CharT __c) {
+ if (__icase_)
+ __neg_chars_.push_back(__traits_.translate_nocase(__c));
+ else if (__collate_)
+ __neg_chars_.push_back(__traits_.translate(__c));
+ else
+ __neg_chars_.push_back(__c);
+ }
+ _LIBCPP_HIDE_FROM_ABI void __add_range(string_type __b, string_type __e) {
+ if (__collate_) {
+ if (__icase_) {
+ for (size_t __i = 0; __i < __b.size(); ++__i)
+ __b[__i] = __traits_.translate_nocase(__b[__i]);
+ for (size_t __i = 0; __i < __e.size(); ++__i)
+ __e[__i] = __traits_.translate_nocase(__e[__i]);
+ } else {
+ for (size_t __i = 0; __i < __b.size(); ++__i)
+ __b[__i] = __traits_.translate(__b[__i]);
+ for (size_t __i = 0; __i < __e.size(); ++__i)
+ __e[__i] = __traits_.translate(__e[__i]);
+ }
+ __ranges_.push_back(
+ std::make_pair(__traits_.transform(__b.begin(), __b.end()), __traits_.transform(__e.begin(), __e.end())));
+ } else {
+ if (__b.size() != 1 || __e.size() != 1)
+ __throw_regex_error<regex_constants::error_range>();
+ if (__icase_) {
+ __b[0] = __traits_.translate_nocase(__b[0]);
+ __e[0] = __traits_.translate_nocase(__e[0]);
+ }
+ __ranges_.push_back(std::make_pair(std::move(__b), std::move(__e)));
+ }
+ }
+ _LIBCPP_HIDE_FROM_ABI void __add_digraph(_CharT __c1, _CharT __c2) {
+ if (__icase_)
+ __digraphs_.push_back(std::make_pair(__traits_.translate_nocase(__c1), __traits_.translate_nocase(__c2)));
+ else if (__collate_)
+ __digraphs_.push_back(std::make_pair(__traits_.translate(__c1), __traits_.translate(__c2)));
+ else
+ __digraphs_.push_back(std::make_pair(__c1, __c2));
+ }
+ _LIBCPP_HIDE_FROM_ABI void __add_equivalence(const string_type& __s) { __equivalences_.push_back(__s); }
+ _LIBCPP_HIDE_FROM_ABI void __add_class(typename regex_traits<_CharT>::char_class_type __mask) { __mask_ |= __mask; }
+ _LIBCPP_HIDE_FROM_ABI void __add_neg_class(typename regex_traits<_CharT>::char_class_type __mask) {
+ __neg_mask_ |= __mask;
+ }
+};
+
+template <class _CharT, class _Traits>
+void __bracket_expression<_CharT, _Traits>::__exec(__state& __s) const {
+ bool __found = false;
+ unsigned __consumed = 0;
+ if (__s.__current_ != __s.__last_) {
+ ++__consumed;
+ if (__might_have_digraph_) {
+ const _CharT* __next = std::next(__s.__current_);
+ if (__next != __s.__last_) {
+ pair<_CharT, _CharT> __ch2(*__s.__current_, *__next);
+ if (__icase_) {
+ __ch2.first = __traits_.translate_nocase(__ch2.first);
+ __ch2.second = __traits_.translate_nocase(__ch2.second);
+ } else if (__collate_) {
+ __ch2.first = __traits_.translate(__ch2.first);
+ __ch2.second = __traits_.translate(__ch2.second);
+ }
+ if (!__traits_.lookup_collatename(&__ch2.first, &__ch2.first + 2).empty()) {
+ // __ch2 is a digraph in this locale
+ ++__consumed;
+ for (size_t __i = 0; __i < __digraphs_.size(); ++__i) {
+ if (__ch2 == __digraphs_[__i]) {
+ __found = true;
+ goto __exit;
+ }
+ }
+ if (__collate_ && !__ranges_.empty()) {
+ string_type __s2 = __traits_.transform(&__ch2.first, &__ch2.first + 2);
+ for (size_t __i = 0; __i < __ranges_.size(); ++__i) {
+ if (__ranges_[__i].first <= __s2 && __s2 <= __ranges_[__i].second) {
+ __found = true;
+ goto __exit;
+ }
+ }
+ }
+ if (!__equivalences_.empty()) {
+ string_type __s2 = __traits_.transform_primary(&__ch2.first, &__ch2.first + 2);
+ for (size_t __i = 0; __i < __equivalences_.size(); ++__i) {
+ if (__s2 == __equivalences_[__i]) {
+ __found = true;
+ goto __exit;
+ }
+ }
+ }
+ if (__traits_.isctype(__ch2.first, __mask_) && __traits_.isctype(__ch2.second, __mask_)) {
+ __found = true;
+ goto __exit;
+ }
+ if (!__traits_.isctype(__ch2.first, __neg_mask_) && !__traits_.isctype(__ch2.second, __neg_mask_)) {
+ __found = true;
+ goto __exit;
+ }
+ goto __exit;
+ }
+ }
+ }
+ // test *__s.__current_ as not a digraph
+ _CharT __ch = *__s.__current_;
+ if (__icase_)
+ __ch = __traits_.translate_nocase(__ch);
+ else if (__collate_)
+ __ch = __traits_.translate(__ch);
+ for (size_t __i = 0; __i < __chars_.size(); ++__i) {
+ if (__ch == __chars_[__i]) {
+ __found = true;
+ goto __exit;
+ }
+ }
+ // When there's at least one of __neg_chars_ and __neg_mask_, the set
+ // of "__found" chars is
+ // union(complement(union(__neg_chars_, __neg_mask_)),
+ // other cases...)
+ //
+ // It doesn't make sense to check this when there are no __neg_chars_
+ // and no __neg_mask_.
+ if (!(__neg_mask_ == 0 && __neg_chars_.empty())) {
+ const bool __in_neg_mask = __traits_.isctype(__ch, __neg_mask_);
+ const bool __in_neg_chars = std::find(__neg_chars_.begin(), __neg_chars_.end(), __ch) != __neg_chars_.end();
+ if (!(__in_neg_mask || __in_neg_chars)) {
+ __found = true;
+ goto __exit;
+ }
+ }
+ if (!__ranges_.empty()) {
+ string_type __s2 = __collate_ ? __traits_.transform(&__ch, &__ch + 1) : string_type(1, __ch);
+ for (size_t __i = 0; __i < __ranges_.size(); ++__i) {
+ if (__ranges_[__i].first <= __s2 && __s2 <= __ranges_[__i].second) {
+ __found = true;
+ goto __exit;
+ }
+ }
+ }
+ if (!__equivalences_.empty()) {
+ string_type __s2 = __traits_.transform_primary(&__ch, &__ch + 1);
+ for (size_t __i = 0; __i < __equivalences_.size(); ++__i) {
+ if (__s2 == __equivalences_[__i]) {
+ __found = true;
+ goto __exit;
+ }
+ }
+ }
+ if (__traits_.isctype(__ch, __mask_)) {
+ __found = true;
+ goto __exit;
+ }
+ } else
+ __found = __negate_; // force reject
+__exit:
+ if (__found != __negate_) {
+ __s.__do_ = __state::__accept_and_consume;
+ __s.__current_ += __consumed;
+ __s.__node_ = this->first();
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+template <class _CharT, class _Traits>
+class __lookahead;
+
+template <class _CharT, class _Traits = regex_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS basic_regex;
+
+typedef basic_regex<char> regex;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+typedef basic_regex<wchar_t> wregex;
+#endif
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_PREFERRED_NAME(regex)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wregex)) basic_regex {
+public:
+ // types:
+ typedef _CharT value_type;
+ typedef _Traits traits_type;
+ typedef typename _Traits::string_type string_type;
+ typedef regex_constants::syntax_option_type flag_type;
+ typedef typename _Traits::locale_type locale_type;
+
+private:
+ _Traits __traits_;
+ flag_type __flags_;
+ unsigned __marked_count_;
+ unsigned __loop_count_;
+ int __open_count_;
+ shared_ptr<__empty_state<_CharT> > __start_;
+ __owns_one_state<_CharT>* __end_;
+
+ typedef std::__state<_CharT> __state;
+ typedef std::__node<_CharT> __node;
+
+public:
+ // constants:
+ static const regex_constants::syntax_option_type icase = regex_constants::icase;
+ static const regex_constants::syntax_option_type nosubs = regex_constants::nosubs;
+ static const regex_constants::syntax_option_type optimize = regex_constants::optimize;
+ static const regex_constants::syntax_option_type collate = regex_constants::collate;
+ static const regex_constants::syntax_option_type ECMAScript = regex_constants::ECMAScript;
+ static const regex_constants::syntax_option_type basic = regex_constants::basic;
+ static const regex_constants::syntax_option_type extended = regex_constants::extended;
+ static const regex_constants::syntax_option_type awk = regex_constants::awk;
+ static const regex_constants::syntax_option_type grep = regex_constants::grep;
+ static const regex_constants::syntax_option_type egrep = regex_constants::egrep;
+ static const regex_constants::syntax_option_type multiline = regex_constants::multiline;
+
+ // construct/copy/destroy:
+ _LIBCPP_HIDE_FROM_ABI basic_regex()
+ : __flags_(regex_constants::ECMAScript),
+ __marked_count_(0),
+ __loop_count_(0),
+ __open_count_(0),
+ __end_(nullptr) {}
+ _LIBCPP_HIDE_FROM_ABI explicit basic_regex(const value_type* __p, flag_type __f = regex_constants::ECMAScript)
+ : __flags_(__f), __marked_count_(0), __loop_count_(0), __open_count_(0), __end_(nullptr) {
+ __init(__p, __p + __traits_.length(__p));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_regex(const value_type* __p, size_t __len, flag_type __f = regex_constants::ECMAScript)
+ : __flags_(__f), __marked_count_(0), __loop_count_(0), __open_count_(0), __end_(nullptr) {
+ __init(__p, __p + __len);
+ }
+
+ // basic_regex(const basic_regex&) = default;
+ // basic_regex(basic_regex&&) = default;
+ template <class _ST, class _SA>
+ _LIBCPP_HIDE_FROM_ABI explicit basic_regex(const basic_string<value_type, _ST, _SA>& __p,
+ flag_type __f = regex_constants::ECMAScript)
+ : __flags_(__f), __marked_count_(0), __loop_count_(0), __open_count_(0), __end_(nullptr) {
+ __init(__p.begin(), __p.end());
+ }
+
+ template <class _ForwardIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ basic_regex(_ForwardIterator __first, _ForwardIterator __last, flag_type __f = regex_constants::ECMAScript)
+ : __flags_(__f), __marked_count_(0), __loop_count_(0), __open_count_(0), __end_(nullptr) {
+ __init(__first, __last);
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI basic_regex(initializer_list<value_type> __il, flag_type __f = regex_constants::ECMAScript)
+ : __flags_(__f), __marked_count_(0), __loop_count_(0), __open_count_(0), __end_(nullptr) {
+ __init(__il.begin(), __il.end());
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ // ~basic_regex() = default;
+
+ // basic_regex& operator=(const basic_regex&) = default;
+ // basic_regex& operator=(basic_regex&&) = default;
+ _LIBCPP_HIDE_FROM_ABI basic_regex& operator=(const value_type* __p) { return assign(__p); }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI basic_regex& operator=(initializer_list<value_type> __il) { return assign(__il); }
+#endif // _LIBCPP_CXX03_LANG
+ template <class _ST, class _SA>
+ _LIBCPP_HIDE_FROM_ABI basic_regex& operator=(const basic_string<value_type, _ST, _SA>& __p) {
+ return assign(__p);
+ }
+
+ // assign:
+ _LIBCPP_HIDE_FROM_ABI basic_regex& assign(const basic_regex& __that) { return *this = __that; }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI basic_regex& assign(basic_regex&& __that) _NOEXCEPT { return *this = std::move(__that); }
+#endif
+ _LIBCPP_HIDE_FROM_ABI basic_regex& assign(const value_type* __p, flag_type __f = regex_constants::ECMAScript) {
+ return assign(__p, __p + __traits_.length(__p), __f);
+ }
+ _LIBCPP_HIDE_FROM_ABI basic_regex&
+ assign(const value_type* __p, size_t __len, flag_type __f = regex_constants::ECMAScript) {
+ return assign(__p, __p + __len, __f);
+ }
+ template <class _ST, class _SA>
+ _LIBCPP_HIDE_FROM_ABI basic_regex&
+ assign(const basic_string<value_type, _ST, _SA>& __s, flag_type __f = regex_constants::ECMAScript) {
+ return assign(__s.begin(), __s.end(), __f);
+ }
+
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI basic_regex&
+ assign(_InputIterator __first, _InputIterator __last, flag_type __f = regex_constants::ECMAScript) {
+ basic_string<_CharT> __t(__first, __last);
+ return assign(__t.begin(), __t.end(), __f);
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI void __member_init(flag_type __f) {
+ __flags_ = __f;
+ __marked_count_ = 0;
+ __loop_count_ = 0;
+ __open_count_ = 0;
+ __end_ = nullptr;
+ }
+
+public:
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI basic_regex&
+ assign(_ForwardIterator __first, _ForwardIterator __last, flag_type __f = regex_constants::ECMAScript) {
+ return assign(basic_regex(__first, __last, __f));
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI basic_regex&
+ assign(initializer_list<value_type> __il, flag_type __f = regex_constants::ECMAScript) {
+ return assign(__il.begin(), __il.end(), __f);
+ }
+
+#endif // _LIBCPP_CXX03_LANG
+
+ // const operations:
+ _LIBCPP_HIDE_FROM_ABI unsigned mark_count() const { return __marked_count_; }
+ _LIBCPP_HIDE_FROM_ABI flag_type flags() const { return __flags_; }
+
+ // locale:
+ _LIBCPP_HIDE_FROM_ABI locale_type imbue(locale_type __loc) {
+ __member_init(ECMAScript);
+ __start_.reset();
+ return __traits_.imbue(__loc);
+ }
+ _LIBCPP_HIDE_FROM_ABI locale_type getloc() const { return __traits_.getloc(); }
+
+ // swap:
+ void swap(basic_regex& __r);
+
+private:
+ _LIBCPP_HIDE_FROM_ABI unsigned __loop_count() const { return __loop_count_; }
+
+ _LIBCPP_HIDE_FROM_ABI bool __use_multiline() const {
+ return __get_grammar(__flags_) == ECMAScript && (__flags_ & multiline);
+ }
+
+ template <class _ForwardIterator>
+ void __init(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_basic_reg_exp(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_RE_expression(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_simple_RE(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_nondupl_RE(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_one_char_or_coll_elem_RE(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_Back_open_paren(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_Back_close_paren(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_Back_open_brace(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_Back_close_brace(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_BACKREF(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_ORD_CHAR(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_QUOTED_CHAR(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_RE_dupl_symbol(
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ __owns_one_state<_CharT>* __s,
+ unsigned __mexp_begin,
+ unsigned __mexp_end);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_ERE_dupl_symbol(
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ __owns_one_state<_CharT>* __s,
+ unsigned __mexp_begin,
+ unsigned __mexp_end);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_bracket_expression(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator
+ __parse_follow_list(_ForwardIterator __first, _ForwardIterator __last, __bracket_expression<_CharT, _Traits>* __ml);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_expression_term(
+ _ForwardIterator __first, _ForwardIterator __last, __bracket_expression<_CharT, _Traits>* __ml);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_equivalence_class(
+ _ForwardIterator __first, _ForwardIterator __last, __bracket_expression<_CharT, _Traits>* __ml);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_character_class(
+ _ForwardIterator __first, _ForwardIterator __last, __bracket_expression<_CharT, _Traits>* __ml);
+ template <class _ForwardIterator>
+ _ForwardIterator
+ __parse_collating_symbol(_ForwardIterator __first, _ForwardIterator __last, basic_string<_CharT>& __col_sym);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_DUP_COUNT(_ForwardIterator __first, _ForwardIterator __last, int& __c);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_extended_reg_exp(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_ERE_branch(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_ERE_expression(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_one_char_or_coll_elem_ERE(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_ORD_CHAR_ERE(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_QUOTED_CHAR_ERE(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_ecma_exp(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_alternative(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_term(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_assertion(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_atom(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_atom_escape(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_decimal_escape(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_character_class_escape(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator
+ __parse_character_escape(_ForwardIterator __first, _ForwardIterator __last, basic_string<_CharT>* __str = nullptr);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_pattern_character(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_grep(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_egrep(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator>
+ _ForwardIterator __parse_class_escape(
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ basic_string<_CharT>& __str,
+ __bracket_expression<_CharT, _Traits>* __ml);
+ template <class _ForwardIterator>
+ _ForwardIterator
+ __parse_awk_escape(_ForwardIterator __first, _ForwardIterator __last, basic_string<_CharT>* __str = nullptr);
+
+ bool __test_back_ref(_CharT);
+
+ _LIBCPP_HIDE_FROM_ABI void __push_l_anchor();
+ void __push_r_anchor();
+ void __push_match_any();
+ void __push_match_any_but_newline();
+ _LIBCPP_HIDE_FROM_ABI void __push_greedy_inf_repeat(
+ size_t __min, __owns_one_state<_CharT>* __s, unsigned __mexp_begin = 0, unsigned __mexp_end = 0) {
+ __push_loop(__min, numeric_limits<size_t>::max(), __s, __mexp_begin, __mexp_end);
+ }
+ _LIBCPP_HIDE_FROM_ABI void __push_nongreedy_inf_repeat(
+ size_t __min, __owns_one_state<_CharT>* __s, unsigned __mexp_begin = 0, unsigned __mexp_end = 0) {
+ __push_loop(__min, numeric_limits<size_t>::max(), __s, __mexp_begin, __mexp_end, false);
+ }
+ void __push_loop(size_t __min,
+ size_t __max,
+ __owns_one_state<_CharT>* __s,
+ size_t __mexp_begin = 0,
+ size_t __mexp_end = 0,
+ bool __greedy = true);
+ __bracket_expression<_CharT, _Traits>* __start_matching_list(bool __negate);
+ void __push_char(value_type __c);
+ void __push_back_ref(int __i);
+ void __push_alternation(__owns_one_state<_CharT>* __sa, __owns_one_state<_CharT>* __sb);
+ void __push_begin_marked_subexpression();
+ void __push_end_marked_subexpression(unsigned);
+ void __push_empty();
+ void __push_word_boundary(bool);
+ void __push_lookahead(const basic_regex&, bool, unsigned);
+
+ template <class _Allocator>
+ bool __search(const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags) const;
+
+ template <class _Allocator>
+ bool __match_at_start(const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags,
+ bool) const;
+ template <class _Allocator>
+ bool __match_at_start_ecma(
+ const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags,
+ bool) const;
+ template <class _Allocator>
+ bool __match_at_start_posix_nosubs(
+ const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags,
+ bool) const;
+ template <class _Allocator>
+ bool __match_at_start_posix_subs(
+ const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags,
+ bool) const;
+
+ template <class _Bp, class _Ap, class _Cp, class _Tp>
+ friend bool
+ regex_search(_Bp, _Bp, match_results<_Bp, _Ap>&, const basic_regex<_Cp, _Tp>&, regex_constants::match_flag_type);
+
+ template <class _Ap, class _Cp, class _Tp>
+ friend bool
+ regex_search(const _Cp*,
+ const _Cp*,
+ match_results<const _Cp*, _Ap>&,
+ const basic_regex<_Cp, _Tp>&,
+ regex_constants::match_flag_type);
+
+ template <class _Bp, class _Cp, class _Tp>
+ friend bool regex_search(_Bp, _Bp, const basic_regex<_Cp, _Tp>&, regex_constants::match_flag_type);
+
+ template <class _Cp, class _Tp>
+ friend bool regex_search(const _Cp*, const _Cp*, const basic_regex<_Cp, _Tp>&, regex_constants::match_flag_type);
+
+ template <class _Cp, class _Ap, class _Tp>
+ friend bool regex_search(
+ const _Cp*, match_results<const _Cp*, _Ap>&, const basic_regex<_Cp, _Tp>&, regex_constants::match_flag_type);
+
+ template <class _ST, class _SA, class _Cp, class _Tp>
+ friend bool regex_search(const basic_string<_Cp, _ST, _SA>& __s,
+ const basic_regex<_Cp, _Tp>& __e,
+ regex_constants::match_flag_type __flags);
+
+ template <class _ST, class _SA, class _Ap, class _Cp, class _Tp>
+ friend bool regex_search(const basic_string<_Cp, _ST, _SA>& __s,
+ match_results<typename basic_string<_Cp, _ST, _SA>::const_iterator, _Ap>&,
+ const basic_regex<_Cp, _Tp>& __e,
+ regex_constants::match_flag_type __flags);
+
+ template <class _Iter, class _Ap, class _Cp, class _Tp>
+ friend bool
+ regex_search(__wrap_iter<_Iter> __first,
+ __wrap_iter<_Iter> __last,
+ match_results<__wrap_iter<_Iter>, _Ap>& __m,
+ const basic_regex<_Cp, _Tp>& __e,
+ regex_constants::match_flag_type __flags);
+
+ template <class, class>
+ friend class __lookahead;
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+basic_regex(_ForwardIterator, _ForwardIterator, regex_constants::syntax_option_type = regex_constants::ECMAScript)
+ -> basic_regex<typename iterator_traits<_ForwardIterator>::value_type>;
+#endif
+
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::icase;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::nosubs;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::optimize;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::collate;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::ECMAScript;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::basic;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::extended;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::awk;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::grep;
+template <class _CharT, class _Traits>
+const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::egrep;
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::swap(basic_regex& __r) {
+ using std::swap;
+ swap(__traits_, __r.__traits_);
+ swap(__flags_, __r.__flags_);
+ swap(__marked_count_, __r.__marked_count_);
+ swap(__loop_count_, __r.__loop_count_);
+ swap(__open_count_, __r.__open_count_);
+ swap(__start_, __r.__start_);
+ swap(__end_, __r.__end_);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI void swap(basic_regex<_CharT, _Traits>& __x, basic_regex<_CharT, _Traits>& __y) {
+ return __x.swap(__y);
+}
+
+// __lookahead
+
+template <class _CharT, class _Traits>
+class __lookahead : public __owns_one_state<_CharT> {
+ typedef __owns_one_state<_CharT> base;
+
+ basic_regex<_CharT, _Traits> __exp_;
+ unsigned __mexp_;
+ bool __invert_;
+
+public:
+ typedef std::__state<_CharT> __state;
+
+ _LIBCPP_HIDE_FROM_ABI
+ __lookahead(const basic_regex<_CharT, _Traits>& __exp, bool __invert, __node<_CharT>* __s, unsigned __mexp)
+ : base(__s), __exp_(__exp), __mexp_(__mexp), __invert_(__invert) {}
+
+ __lookahead(const __lookahead&) = delete;
+ __lookahead& operator=(const __lookahead&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL virtual void __exec(__state&) const;
+};
+
+template <class _CharT, class _Traits>
+void __lookahead<_CharT, _Traits>::__exec(__state& __s) const {
+ match_results<const _CharT*> __m;
+ __m.__init(1 + __exp_.mark_count(), __s.__current_, __s.__last_);
+ bool __matched = __exp_.__match_at_start_ecma(
+ __s.__current_,
+ __s.__last_,
+ __m,
+ (__s.__flags_ | regex_constants::match_continuous) & ~regex_constants::__full_match,
+ __s.__at_first_ && __s.__current_ == __s.__first_);
+ if (__matched != __invert_) {
+ __s.__do_ = __state::__accept_but_not_consume;
+ __s.__node_ = this->first();
+ for (unsigned __i = 1; __i < __m.size(); ++__i) {
+ __s.__sub_matches_[__mexp_ + __i - 1] = __m.__matches_[__i];
+ }
+ } else {
+ __s.__do_ = __state::__reject;
+ __s.__node_ = nullptr;
+ }
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+void basic_regex<_CharT, _Traits>::__init(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__get_grammar(__flags_) == 0)
+ __flags_ |= regex_constants::ECMAScript;
+ _ForwardIterator __temp = __parse(__first, __last);
+ if (__temp != __last)
+ __throw_regex_error<regex_constants::__re_err_parse>();
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse(_ForwardIterator __first, _ForwardIterator __last) {
+ {
+ unique_ptr<__node> __h(new __end_state<_CharT>);
+ __start_.reset(new __empty_state<_CharT>(__h.get()));
+ __h.release();
+ __end_ = __start_.get();
+ }
+ switch (__get_grammar(__flags_)) {
+ case ECMAScript:
+ __first = __parse_ecma_exp(__first, __last);
+ break;
+ case basic:
+ __first = __parse_basic_reg_exp(__first, __last);
+ break;
+ case extended:
+ case awk:
+ __first = __parse_extended_reg_exp(__first, __last);
+ break;
+ case grep:
+ __first = __parse_grep(__first, __last);
+ break;
+ case egrep:
+ __first = __parse_egrep(__first, __last);
+ break;
+ default:
+ __throw_regex_error<regex_constants::__re_err_grammar>();
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_basic_reg_exp(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ if (*__first == '^') {
+ __push_l_anchor();
+ ++__first;
+ }
+ if (__first != __last) {
+ __first = __parse_RE_expression(__first, __last);
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp == __last && *__first == '$') {
+ __push_r_anchor();
+ ++__first;
+ }
+ }
+ }
+ if (__first != __last)
+ __throw_regex_error<regex_constants::__re_err_empty>();
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_extended_reg_exp(_ForwardIterator __first, _ForwardIterator __last) {
+ __owns_one_state<_CharT>* __sa = __end_;
+ _ForwardIterator __temp = __parse_ERE_branch(__first, __last);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::__re_err_empty>();
+ __first = __temp;
+ while (__first != __last && *__first == '|') {
+ __owns_one_state<_CharT>* __sb = __end_;
+ __temp = __parse_ERE_branch(++__first, __last);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::__re_err_empty>();
+ __push_alternation(__sa, __sb);
+ __first = __temp;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_ERE_branch(_ForwardIterator __first, _ForwardIterator __last) {
+ _ForwardIterator __temp = __parse_ERE_expression(__first, __last);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::__re_err_empty>();
+ do {
+ __first = __temp;
+ __temp = __parse_ERE_expression(__first, __last);
+ } while (__temp != __first);
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_ERE_expression(_ForwardIterator __first, _ForwardIterator __last) {
+ __owns_one_state<_CharT>* __e = __end_;
+ unsigned __mexp_begin = __marked_count_;
+ _ForwardIterator __temp = __parse_one_char_or_coll_elem_ERE(__first, __last);
+ if (__temp == __first && __temp != __last) {
+ switch (*__temp) {
+ case '^':
+ __push_l_anchor();
+ ++__temp;
+ break;
+ case '$':
+ __push_r_anchor();
+ ++__temp;
+ break;
+ case '(':
+ __push_begin_marked_subexpression();
+ unsigned __temp_count = __marked_count_;
+ ++__open_count_;
+ __temp = __parse_extended_reg_exp(++__temp, __last);
+ if (__temp == __last || *__temp != ')')
+ __throw_regex_error<regex_constants::error_paren>();
+ __push_end_marked_subexpression(__temp_count);
+ --__open_count_;
+ ++__temp;
+ break;
+ }
+ }
+ if (__temp != __first)
+ __temp = __parse_ERE_dupl_symbol(__temp, __last, __e, __mexp_begin + 1, __marked_count_ + 1);
+ __first = __temp;
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_RE_expression(_ForwardIterator __first, _ForwardIterator __last) {
+ while (true) {
+ _ForwardIterator __temp = __parse_simple_RE(__first, __last);
+ if (__temp == __first)
+ break;
+ __first = __temp;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_simple_RE(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ __owns_one_state<_CharT>* __e = __end_;
+ unsigned __mexp_begin = __marked_count_;
+ _ForwardIterator __temp = __parse_nondupl_RE(__first, __last);
+ if (__temp != __first)
+ __first = __parse_RE_dupl_symbol(__temp, __last, __e, __mexp_begin + 1, __marked_count_ + 1);
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_nondupl_RE(_ForwardIterator __first, _ForwardIterator __last) {
+ _ForwardIterator __temp = __first;
+ __first = __parse_one_char_or_coll_elem_RE(__first, __last);
+ if (__temp == __first) {
+ __temp = __parse_Back_open_paren(__first, __last);
+ if (__temp != __first) {
+ __push_begin_marked_subexpression();
+ unsigned __temp_count = __marked_count_;
+ __first = __parse_RE_expression(__temp, __last);
+ __temp = __parse_Back_close_paren(__first, __last);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::error_paren>();
+ __push_end_marked_subexpression(__temp_count);
+ __first = __temp;
+ } else
+ __first = __parse_BACKREF(__first, __last);
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_one_char_or_coll_elem_RE(_ForwardIterator __first, _ForwardIterator __last) {
+ _ForwardIterator __temp = __parse_ORD_CHAR(__first, __last);
+ if (__temp == __first) {
+ __temp = __parse_QUOTED_CHAR(__first, __last);
+ if (__temp == __first) {
+ if (__temp != __last && *__temp == '.') {
+ __push_match_any();
+ ++__temp;
+ } else
+ __temp = __parse_bracket_expression(__first, __last);
+ }
+ }
+ __first = __temp;
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_one_char_or_coll_elem_ERE(_ForwardIterator __first, _ForwardIterator __last) {
+ _ForwardIterator __temp = __parse_ORD_CHAR_ERE(__first, __last);
+ if (__temp == __first) {
+ __temp = __parse_QUOTED_CHAR_ERE(__first, __last);
+ if (__temp == __first) {
+ if (__temp != __last && *__temp == '.') {
+ __push_match_any();
+ ++__temp;
+ } else
+ __temp = __parse_bracket_expression(__first, __last);
+ }
+ }
+ __first = __temp;
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_Back_open_paren(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last) {
+ if (*__first == '\\' && *__temp == '(')
+ __first = ++__temp;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_Back_close_paren(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last) {
+ if (*__first == '\\' && *__temp == ')')
+ __first = ++__temp;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_Back_open_brace(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last) {
+ if (*__first == '\\' && *__temp == '{')
+ __first = ++__temp;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_Back_close_brace(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last) {
+ if (*__first == '\\' && *__temp == '}')
+ __first = ++__temp;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_BACKREF(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last && *__first == '\\' && __test_back_ref(*__temp))
+ __first = ++__temp;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_ORD_CHAR(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp == __last && *__first == '$')
+ return __first;
+ // Not called inside a bracket
+ if (*__first == '.' || *__first == '\\' || *__first == '[')
+ return __first;
+ __push_char(*__first);
+ ++__first;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_ORD_CHAR_ERE(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ switch (*__first) {
+ case '^':
+ case '.':
+ case '[':
+ case '$':
+ case '(':
+ case '|':
+ case '*':
+ case '+':
+ case '?':
+ case '{':
+ case '\\':
+ break;
+ case ')':
+ if (__open_count_ == 0) {
+ __push_char(*__first);
+ ++__first;
+ }
+ break;
+ default:
+ __push_char(*__first);
+ ++__first;
+ break;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_QUOTED_CHAR(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last) {
+ if (*__first == '\\') {
+ switch (*__temp) {
+ case '^':
+ case '.':
+ case '*':
+ case '[':
+ case '$':
+ case '\\':
+ __push_char(*__temp);
+ __first = ++__temp;
+ break;
+ }
+ }
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_QUOTED_CHAR_ERE(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last) {
+ if (*__first == '\\') {
+ switch (*__temp) {
+ case '^':
+ case '.':
+ case '*':
+ case '[':
+ case '$':
+ case '\\':
+ case '(':
+ case ')':
+ case '|':
+ case '+':
+ case '?':
+ case '{':
+ case '}':
+ __push_char(*__temp);
+ __first = ++__temp;
+ break;
+ default:
+ if (__get_grammar(__flags_) == awk)
+ __first = __parse_awk_escape(++__first, __last);
+ else if (__test_back_ref(*__temp))
+ __first = ++__temp;
+ break;
+ }
+ }
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_RE_dupl_symbol(
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ __owns_one_state<_CharT>* __s,
+ unsigned __mexp_begin,
+ unsigned __mexp_end) {
+ if (__first != __last) {
+ if (*__first == '*') {
+ __push_greedy_inf_repeat(0, __s, __mexp_begin, __mexp_end);
+ ++__first;
+ } else {
+ _ForwardIterator __temp = __parse_Back_open_brace(__first, __last);
+ if (__temp != __first) {
+ int __min = 0;
+ __first = __temp;
+ __temp = __parse_DUP_COUNT(__first, __last, __min);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::error_badbrace>();
+ __first = __temp;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_brace>();
+ if (*__first != ',') {
+ __temp = __parse_Back_close_brace(__first, __last);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::error_brace>();
+ __push_loop(__min, __min, __s, __mexp_begin, __mexp_end, true);
+ __first = __temp;
+ } else {
+ ++__first; // consume ','
+ int __max = -1;
+ __first = __parse_DUP_COUNT(__first, __last, __max);
+ __temp = __parse_Back_close_brace(__first, __last);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::error_brace>();
+ if (__max == -1)
+ __push_greedy_inf_repeat(__min, __s, __mexp_begin, __mexp_end);
+ else {
+ if (__max < __min)
+ __throw_regex_error<regex_constants::error_badbrace>();
+ __push_loop(__min, __max, __s, __mexp_begin, __mexp_end, true);
+ }
+ __first = __temp;
+ }
+ }
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_ERE_dupl_symbol(
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ __owns_one_state<_CharT>* __s,
+ unsigned __mexp_begin,
+ unsigned __mexp_end) {
+ if (__first != __last) {
+ unsigned __grammar = __get_grammar(__flags_);
+ switch (*__first) {
+ case '*':
+ ++__first;
+ if (__grammar == ECMAScript && __first != __last && *__first == '?') {
+ ++__first;
+ __push_nongreedy_inf_repeat(0, __s, __mexp_begin, __mexp_end);
+ } else
+ __push_greedy_inf_repeat(0, __s, __mexp_begin, __mexp_end);
+ break;
+ case '+':
+ ++__first;
+ if (__grammar == ECMAScript && __first != __last && *__first == '?') {
+ ++__first;
+ __push_nongreedy_inf_repeat(1, __s, __mexp_begin, __mexp_end);
+ } else
+ __push_greedy_inf_repeat(1, __s, __mexp_begin, __mexp_end);
+ break;
+ case '?':
+ ++__first;
+ if (__grammar == ECMAScript && __first != __last && *__first == '?') {
+ ++__first;
+ __push_loop(0, 1, __s, __mexp_begin, __mexp_end, false);
+ } else
+ __push_loop(0, 1, __s, __mexp_begin, __mexp_end);
+ break;
+ case '{': {
+ int __min;
+ _ForwardIterator __temp = __parse_DUP_COUNT(++__first, __last, __min);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::error_badbrace>();
+ __first = __temp;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_brace>();
+ switch (*__first) {
+ case '}':
+ ++__first;
+ if (__grammar == ECMAScript && __first != __last && *__first == '?') {
+ ++__first;
+ __push_loop(__min, __min, __s, __mexp_begin, __mexp_end, false);
+ } else
+ __push_loop(__min, __min, __s, __mexp_begin, __mexp_end);
+ break;
+ case ',':
+ ++__first;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_badbrace>();
+ if (*__first == '}') {
+ ++__first;
+ if (__grammar == ECMAScript && __first != __last && *__first == '?') {
+ ++__first;
+ __push_nongreedy_inf_repeat(__min, __s, __mexp_begin, __mexp_end);
+ } else
+ __push_greedy_inf_repeat(__min, __s, __mexp_begin, __mexp_end);
+ } else {
+ int __max = -1;
+ __temp = __parse_DUP_COUNT(__first, __last, __max);
+ if (__temp == __first)
+ __throw_regex_error<regex_constants::error_brace>();
+ __first = __temp;
+ if (__first == __last || *__first != '}')
+ __throw_regex_error<regex_constants::error_brace>();
+ ++__first;
+ if (__max < __min)
+ __throw_regex_error<regex_constants::error_badbrace>();
+ if (__grammar == ECMAScript && __first != __last && *__first == '?') {
+ ++__first;
+ __push_loop(__min, __max, __s, __mexp_begin, __mexp_end, false);
+ } else
+ __push_loop(__min, __max, __s, __mexp_begin, __mexp_end);
+ }
+ break;
+ default:
+ __throw_regex_error<regex_constants::error_badbrace>();
+ }
+ } break;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_bracket_expression(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last && *__first == '[') {
+ ++__first;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_brack>();
+ bool __negate = false;
+ if (*__first == '^') {
+ ++__first;
+ __negate = true;
+ }
+ __bracket_expression<_CharT, _Traits>* __ml = __start_matching_list(__negate);
+ // __ml owned by *this
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_brack>();
+ if (__get_grammar(__flags_) != ECMAScript && *__first == ']') {
+ __ml->__add_char(']');
+ ++__first;
+ }
+ __first = __parse_follow_list(__first, __last, __ml);
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_brack>();
+ if (*__first == '-') {
+ __ml->__add_char('-');
+ ++__first;
+ }
+ if (__first == __last || *__first != ']')
+ __throw_regex_error<regex_constants::error_brack>();
+ ++__first;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_follow_list(
+ _ForwardIterator __first, _ForwardIterator __last, __bracket_expression<_CharT, _Traits>* __ml) {
+ if (__first != __last) {
+ while (true) {
+ _ForwardIterator __temp = __parse_expression_term(__first, __last, __ml);
+ if (__temp == __first)
+ break;
+ __first = __temp;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_expression_term(
+ _ForwardIterator __first, _ForwardIterator __last, __bracket_expression<_CharT, _Traits>* __ml) {
+ if (__first != __last && *__first != ']') {
+ _ForwardIterator __temp = std::next(__first);
+ basic_string<_CharT> __start_range;
+ if (__temp != __last && *__first == '[') {
+ if (*__temp == '=')
+ return __parse_equivalence_class(++__temp, __last, __ml);
+ else if (*__temp == ':')
+ return __parse_character_class(++__temp, __last, __ml);
+ else if (*__temp == '.')
+ __first = __parse_collating_symbol(++__temp, __last, __start_range);
+ }
+ unsigned __grammar = __get_grammar(__flags_);
+ if (__start_range.empty()) {
+ if ((__grammar == ECMAScript || __grammar == awk) && *__first == '\\') {
+ if (__grammar == ECMAScript)
+ __first = __parse_class_escape(++__first, __last, __start_range, __ml);
+ else
+ __first = __parse_awk_escape(++__first, __last, &__start_range);
+ } else {
+ __start_range = *__first;
+ ++__first;
+ }
+ }
+ if (__first != __last && *__first != ']') {
+ __temp = std::next(__first);
+ if (__temp != __last && *__first == '-' && *__temp != ']') {
+ // parse a range
+ basic_string<_CharT> __end_range;
+ __first = __temp;
+ ++__temp;
+ if (__temp != __last && *__first == '[' && *__temp == '.')
+ __first = __parse_collating_symbol(++__temp, __last, __end_range);
+ else {
+ if ((__grammar == ECMAScript || __grammar == awk) && *__first == '\\') {
+ if (__grammar == ECMAScript)
+ __first = __parse_class_escape(++__first, __last, __end_range, __ml);
+ else
+ __first = __parse_awk_escape(++__first, __last, &__end_range);
+ } else {
+ __end_range = *__first;
+ ++__first;
+ }
+ }
+ __ml->__add_range(std::move(__start_range), std::move(__end_range));
+ } else if (!__start_range.empty()) {
+ if (__start_range.size() == 1)
+ __ml->__add_char(__start_range[0]);
+ else
+ __ml->__add_digraph(__start_range[0], __start_range[1]);
+ }
+ } else if (!__start_range.empty()) {
+ if (__start_range.size() == 1)
+ __ml->__add_char(__start_range[0]);
+ else
+ __ml->__add_digraph(__start_range[0], __start_range[1]);
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_class_escape(
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ basic_string<_CharT>& __str,
+ __bracket_expression<_CharT, _Traits>* __ml) {
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_escape>();
+ switch (*__first) {
+ case 0:
+ __str = *__first;
+ return ++__first;
+ case 'b':
+ __str = _CharT(8);
+ return ++__first;
+ case 'd':
+ __ml->__add_class(ctype_base::digit);
+ return ++__first;
+ case 'D':
+ __ml->__add_neg_class(ctype_base::digit);
+ return ++__first;
+ case 's':
+ __ml->__add_class(ctype_base::space);
+ return ++__first;
+ case 'S':
+ __ml->__add_neg_class(ctype_base::space);
+ return ++__first;
+ case 'w':
+ __ml->__add_class(ctype_base::alnum);
+ __ml->__add_char('_');
+ return ++__first;
+ case 'W':
+ __ml->__add_neg_class(ctype_base::alnum);
+ __ml->__add_neg_char('_');
+ return ++__first;
+ }
+ __first = __parse_character_escape(__first, __last, &__str);
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_awk_escape(
+ _ForwardIterator __first, _ForwardIterator __last, basic_string<_CharT>* __str) {
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_escape>();
+ switch (*__first) {
+ case '\\':
+ case '"':
+ case '/':
+ if (__str)
+ *__str = *__first;
+ else
+ __push_char(*__first);
+ return ++__first;
+ case 'a':
+ if (__str)
+ *__str = _CharT(7);
+ else
+ __push_char(_CharT(7));
+ return ++__first;
+ case 'b':
+ if (__str)
+ *__str = _CharT(8);
+ else
+ __push_char(_CharT(8));
+ return ++__first;
+ case 'f':
+ if (__str)
+ *__str = _CharT(0xC);
+ else
+ __push_char(_CharT(0xC));
+ return ++__first;
+ case 'n':
+ if (__str)
+ *__str = _CharT(0xA);
+ else
+ __push_char(_CharT(0xA));
+ return ++__first;
+ case 'r':
+ if (__str)
+ *__str = _CharT(0xD);
+ else
+ __push_char(_CharT(0xD));
+ return ++__first;
+ case 't':
+ if (__str)
+ *__str = _CharT(0x9);
+ else
+ __push_char(_CharT(0x9));
+ return ++__first;
+ case 'v':
+ if (__str)
+ *__str = _CharT(0xB);
+ else
+ __push_char(_CharT(0xB));
+ return ++__first;
+ }
+ if ('0' <= *__first && *__first <= '7') {
+ unsigned __val = *__first - '0';
+ if (++__first != __last && ('0' <= *__first && *__first <= '7')) {
+ __val = 8 * __val + *__first - '0';
+ if (++__first != __last && ('0' <= *__first && *__first <= '7'))
+ __val = 8 * __val + *__first++ - '0';
+ }
+ if (__str)
+ *__str = _CharT(__val);
+ else
+ __push_char(_CharT(__val));
+ } else
+ __throw_regex_error<regex_constants::error_escape>();
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_equivalence_class(
+ _ForwardIterator __first, _ForwardIterator __last, __bracket_expression<_CharT, _Traits>* __ml) {
+ // Found [=
+ // This means =] must exist
+ value_type __equal_close[2] = {'=', ']'};
+ _ForwardIterator __temp = std::search(__first, __last, __equal_close, __equal_close + 2);
+ if (__temp == __last)
+ __throw_regex_error<regex_constants::error_brack>();
+ // [__first, __temp) contains all text in [= ... =]
+ string_type __collate_name = __traits_.lookup_collatename(__first, __temp);
+ if (__collate_name.empty())
+ __throw_regex_error<regex_constants::error_collate>();
+ string_type __equiv_name = __traits_.transform_primary(__collate_name.begin(), __collate_name.end());
+ if (!__equiv_name.empty())
+ __ml->__add_equivalence(__equiv_name);
+ else {
+ switch (__collate_name.size()) {
+ case 1:
+ __ml->__add_char(__collate_name[0]);
+ break;
+ case 2:
+ __ml->__add_digraph(__collate_name[0], __collate_name[1]);
+ break;
+ default:
+ __throw_regex_error<regex_constants::error_collate>();
+ }
+ }
+ __first = std::next(__temp, 2);
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_character_class(
+ _ForwardIterator __first, _ForwardIterator __last, __bracket_expression<_CharT, _Traits>* __ml) {
+ // Found [:
+ // This means :] must exist
+ value_type __colon_close[2] = {':', ']'};
+ _ForwardIterator __temp = std::search(__first, __last, __colon_close, __colon_close + 2);
+ if (__temp == __last)
+ __throw_regex_error<regex_constants::error_brack>();
+ // [__first, __temp) contains all text in [: ... :]
+ typedef typename _Traits::char_class_type char_class_type;
+ char_class_type __class_type = __traits_.lookup_classname(__first, __temp, __flags_ & icase);
+ if (__class_type == 0)
+ __throw_regex_error<regex_constants::error_ctype>();
+ __ml->__add_class(__class_type);
+ __first = std::next(__temp, 2);
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_collating_symbol(
+ _ForwardIterator __first, _ForwardIterator __last, basic_string<_CharT>& __col_sym) {
+ // Found [.
+ // This means .] must exist
+ value_type __dot_close[2] = {'.', ']'};
+ _ForwardIterator __temp = std::search(__first, __last, __dot_close, __dot_close + 2);
+ if (__temp == __last)
+ __throw_regex_error<regex_constants::error_brack>();
+ // [__first, __temp) contains all text in [. ... .]
+ __col_sym = __traits_.lookup_collatename(__first, __temp);
+ switch (__col_sym.size()) {
+ case 1:
+ case 2:
+ break;
+ default:
+ __throw_regex_error<regex_constants::error_collate>();
+ }
+ __first = std::next(__temp, 2);
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_DUP_COUNT(_ForwardIterator __first, _ForwardIterator __last, int& __c) {
+ if (__first != __last) {
+ int __val = __traits_.value(*__first, 10);
+ if (__val != -1) {
+ __c = __val;
+ for (++__first; __first != __last && (__val = __traits_.value(*__first, 10)) != -1; ++__first) {
+ if (__c >= numeric_limits<int>::max() / 10)
+ __throw_regex_error<regex_constants::error_badbrace>();
+ __c *= 10;
+ __c += __val;
+ }
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_ecma_exp(_ForwardIterator __first, _ForwardIterator __last) {
+ __owns_one_state<_CharT>* __sa = __end_;
+ _ForwardIterator __temp = __parse_alternative(__first, __last);
+ if (__temp == __first)
+ __push_empty();
+ __first = __temp;
+ while (__first != __last && *__first == '|') {
+ __owns_one_state<_CharT>* __sb = __end_;
+ __temp = __parse_alternative(++__first, __last);
+ if (__temp == __first)
+ __push_empty();
+ __push_alternation(__sa, __sb);
+ __first = __temp;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_alternative(_ForwardIterator __first, _ForwardIterator __last) {
+ while (true) {
+ _ForwardIterator __temp = __parse_term(__first, __last);
+ if (__temp == __first)
+ break;
+ __first = __temp;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_term(_ForwardIterator __first, _ForwardIterator __last) {
+ _ForwardIterator __temp = __parse_assertion(__first, __last);
+ if (__temp == __first) {
+ __owns_one_state<_CharT>* __e = __end_;
+ unsigned __mexp_begin = __marked_count_;
+ __temp = __parse_atom(__first, __last);
+ if (__temp != __first)
+ __first = __parse_ERE_dupl_symbol(__temp, __last, __e, __mexp_begin + 1, __marked_count_ + 1);
+ } else
+ __first = __temp;
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_assertion(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ switch (*__first) {
+ case '^':
+ __push_l_anchor();
+ ++__first;
+ break;
+ case '$':
+ __push_r_anchor();
+ ++__first;
+ break;
+ case '\\': {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last) {
+ if (*__temp == 'b') {
+ __push_word_boundary(false);
+ __first = ++__temp;
+ } else if (*__temp == 'B') {
+ __push_word_boundary(true);
+ __first = ++__temp;
+ }
+ }
+ } break;
+ case '(': {
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last && *__temp == '?') {
+ if (++__temp != __last) {
+ switch (*__temp) {
+ case '=': {
+ basic_regex __exp;
+ __exp.__flags_ = __flags_;
+ __temp = __exp.__parse(++__temp, __last);
+ unsigned __mexp = __exp.__marked_count_;
+ __push_lookahead(std::move(__exp), false, __marked_count_);
+ __marked_count_ += __mexp;
+ if (__temp == __last || *__temp != ')')
+ __throw_regex_error<regex_constants::error_paren>();
+ __first = ++__temp;
+ } break;
+ case '!': {
+ basic_regex __exp;
+ __exp.__flags_ = __flags_;
+ __temp = __exp.__parse(++__temp, __last);
+ unsigned __mexp = __exp.__marked_count_;
+ __push_lookahead(std::move(__exp), true, __marked_count_);
+ __marked_count_ += __mexp;
+ if (__temp == __last || *__temp != ')')
+ __throw_regex_error<regex_constants::error_paren>();
+ __first = ++__temp;
+ } break;
+ }
+ }
+ }
+ } break;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_atom(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ switch (*__first) {
+ case '.':
+ __push_match_any_but_newline();
+ ++__first;
+ break;
+ case '\\':
+ __first = __parse_atom_escape(__first, __last);
+ break;
+ case '[':
+ __first = __parse_bracket_expression(__first, __last);
+ break;
+ case '(': {
+ ++__first;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_paren>();
+ _ForwardIterator __temp = std::next(__first);
+ if (__temp != __last && *__first == '?' && *__temp == ':') {
+ ++__open_count_;
+ __first = __parse_ecma_exp(++__temp, __last);
+ if (__first == __last || *__first != ')')
+ __throw_regex_error<regex_constants::error_paren>();
+ --__open_count_;
+ ++__first;
+ } else {
+ __push_begin_marked_subexpression();
+ unsigned __temp_count = __marked_count_;
+ ++__open_count_;
+ __first = __parse_ecma_exp(__first, __last);
+ if (__first == __last || *__first != ')')
+ __throw_regex_error<regex_constants::error_paren>();
+ __push_end_marked_subexpression(__temp_count);
+ --__open_count_;
+ ++__first;
+ }
+ } break;
+ case '*':
+ case '+':
+ case '?':
+ case '{':
+ __throw_regex_error<regex_constants::error_badrepeat>();
+ break;
+ default:
+ __first = __parse_pattern_character(__first, __last);
+ break;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_atom_escape(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last && *__first == '\\') {
+ _ForwardIterator __t1 = std::next(__first);
+ if (__t1 == __last)
+ __throw_regex_error<regex_constants::error_escape>();
+
+ _ForwardIterator __t2 = __parse_decimal_escape(__t1, __last);
+ if (__t2 != __t1)
+ __first = __t2;
+ else {
+ __t2 = __parse_character_class_escape(__t1, __last);
+ if (__t2 != __t1)
+ __first = __t2;
+ else {
+ __t2 = __parse_character_escape(__t1, __last);
+ if (__t2 != __t1)
+ __first = __t2;
+ }
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_decimal_escape(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ if (*__first == '0') {
+ __push_char(_CharT());
+ ++__first;
+ } else if ('1' <= *__first && *__first <= '9') {
+ unsigned __v = *__first - '0';
+ for (++__first; __first != __last && '0' <= *__first && *__first <= '9'; ++__first) {
+ if (__v >= numeric_limits<unsigned>::max() / 10)
+ __throw_regex_error<regex_constants::error_backref>();
+ __v = 10 * __v + *__first - '0';
+ }
+ if (__v == 0 || __v > mark_count())
+ __throw_regex_error<regex_constants::error_backref>();
+ __push_back_ref(__v);
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_character_class_escape(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ __bracket_expression<_CharT, _Traits>* __ml;
+ switch (*__first) {
+ case 'd':
+ __ml = __start_matching_list(false);
+ __ml->__add_class(ctype_base::digit);
+ ++__first;
+ break;
+ case 'D':
+ __ml = __start_matching_list(true);
+ __ml->__add_class(ctype_base::digit);
+ ++__first;
+ break;
+ case 's':
+ __ml = __start_matching_list(false);
+ __ml->__add_class(ctype_base::space);
+ ++__first;
+ break;
+ case 'S':
+ __ml = __start_matching_list(true);
+ __ml->__add_class(ctype_base::space);
+ ++__first;
+ break;
+ case 'w':
+ __ml = __start_matching_list(false);
+ __ml->__add_class(ctype_base::alnum);
+ __ml->__add_char('_');
+ ++__first;
+ break;
+ case 'W':
+ __ml = __start_matching_list(true);
+ __ml->__add_class(ctype_base::alnum);
+ __ml->__add_char('_');
+ ++__first;
+ break;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_character_escape(
+ _ForwardIterator __first, _ForwardIterator __last, basic_string<_CharT>* __str) {
+ if (__first != __last) {
+ _ForwardIterator __t;
+ unsigned __sum = 0;
+ int __hd;
+ switch (*__first) {
+ case 'f':
+ if (__str)
+ *__str = _CharT(0xC);
+ else
+ __push_char(_CharT(0xC));
+ ++__first;
+ break;
+ case 'n':
+ if (__str)
+ *__str = _CharT(0xA);
+ else
+ __push_char(_CharT(0xA));
+ ++__first;
+ break;
+ case 'r':
+ if (__str)
+ *__str = _CharT(0xD);
+ else
+ __push_char(_CharT(0xD));
+ ++__first;
+ break;
+ case 't':
+ if (__str)
+ *__str = _CharT(0x9);
+ else
+ __push_char(_CharT(0x9));
+ ++__first;
+ break;
+ case 'v':
+ if (__str)
+ *__str = _CharT(0xB);
+ else
+ __push_char(_CharT(0xB));
+ ++__first;
+ break;
+ case 'c':
+ if ((__t = std::next(__first)) != __last) {
+ if (('A' <= *__t && *__t <= 'Z') || ('a' <= *__t && *__t <= 'z')) {
+ if (__str)
+ *__str = _CharT(*__t % 32);
+ else
+ __push_char(_CharT(*__t % 32));
+ __first = ++__t;
+ } else
+ __throw_regex_error<regex_constants::error_escape>();
+ } else
+ __throw_regex_error<regex_constants::error_escape>();
+ break;
+ case 'u':
+ ++__first;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_escape>();
+ __hd = __traits_.value(*__first, 16);
+ if (__hd == -1)
+ __throw_regex_error<regex_constants::error_escape>();
+ __sum = 16 * __sum + static_cast<unsigned>(__hd);
+ ++__first;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_escape>();
+ __hd = __traits_.value(*__first, 16);
+ if (__hd == -1)
+ __throw_regex_error<regex_constants::error_escape>();
+ __sum = 16 * __sum + static_cast<unsigned>(__hd);
+ // fallthrough
+ case 'x':
+ ++__first;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_escape>();
+ __hd = __traits_.value(*__first, 16);
+ if (__hd == -1)
+ __throw_regex_error<regex_constants::error_escape>();
+ __sum = 16 * __sum + static_cast<unsigned>(__hd);
+ ++__first;
+ if (__first == __last)
+ __throw_regex_error<regex_constants::error_escape>();
+ __hd = __traits_.value(*__first, 16);
+ if (__hd == -1)
+ __throw_regex_error<regex_constants::error_escape>();
+ __sum = 16 * __sum + static_cast<unsigned>(__hd);
+ if (__str)
+ *__str = _CharT(__sum);
+ else
+ __push_char(_CharT(__sum));
+ ++__first;
+ break;
+ case '0':
+ if (__str)
+ *__str = _CharT(0);
+ else
+ __push_char(_CharT(0));
+ ++__first;
+ break;
+ default:
+ if (*__first != '_' && !__traits_.isctype(*__first, ctype_base::alnum)) {
+ if (__str)
+ *__str = *__first;
+ else
+ __push_char(*__first);
+ ++__first;
+ } else
+ __throw_regex_error<regex_constants::error_escape>();
+ break;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator
+basic_regex<_CharT, _Traits>::__parse_pattern_character(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__first != __last) {
+ switch (*__first) {
+ case '^':
+ case '$':
+ case '\\':
+ case '.':
+ case '*':
+ case '+':
+ case '?':
+ case '(':
+ case ')':
+ case '[':
+ case ']':
+ case '{':
+ case '}':
+ case '|':
+ break;
+ default:
+ __push_char(*__first);
+ ++__first;
+ break;
+ }
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_grep(_ForwardIterator __first, _ForwardIterator __last) {
+ __owns_one_state<_CharT>* __sa = __end_;
+ _ForwardIterator __t1 = std::find(__first, __last, _CharT('\n'));
+ if (__t1 != __first)
+ __parse_basic_reg_exp(__first, __t1);
+ else
+ __push_empty();
+ __first = __t1;
+ if (__first != __last)
+ ++__first;
+ while (__first != __last) {
+ __t1 = std::find(__first, __last, _CharT('\n'));
+ __owns_one_state<_CharT>* __sb = __end_;
+ if (__t1 != __first)
+ __parse_basic_reg_exp(__first, __t1);
+ else
+ __push_empty();
+ __push_alternation(__sa, __sb);
+ __first = __t1;
+ if (__first != __last)
+ ++__first;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+template <class _ForwardIterator>
+_ForwardIterator basic_regex<_CharT, _Traits>::__parse_egrep(_ForwardIterator __first, _ForwardIterator __last) {
+ __owns_one_state<_CharT>* __sa = __end_;
+ _ForwardIterator __t1 = std::find(__first, __last, _CharT('\n'));
+ if (__t1 != __first)
+ __parse_extended_reg_exp(__first, __t1);
+ else
+ __push_empty();
+ __first = __t1;
+ if (__first != __last)
+ ++__first;
+ while (__first != __last) {
+ __t1 = std::find(__first, __last, _CharT('\n'));
+ __owns_one_state<_CharT>* __sb = __end_;
+ if (__t1 != __first)
+ __parse_extended_reg_exp(__first, __t1);
+ else
+ __push_empty();
+ __push_alternation(__sa, __sb);
+ __first = __t1;
+ if (__first != __last)
+ ++__first;
+ }
+ return __first;
+}
+
+template <class _CharT, class _Traits>
+bool basic_regex<_CharT, _Traits>::__test_back_ref(_CharT __c) {
+ unsigned __val = __traits_.value(__c, 10);
+ if (__val >= 1 && __val <= 9) {
+ if (__val > mark_count())
+ __throw_regex_error<regex_constants::error_backref>();
+ __push_back_ref(__val);
+ return true;
+ }
+
+ return false;
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_loop(
+ size_t __min, size_t __max, __owns_one_state<_CharT>* __s, size_t __mexp_begin, size_t __mexp_end, bool __greedy) {
+ unique_ptr<__empty_state<_CharT> > __e1(new __empty_state<_CharT>(__end_->first()));
+ __end_->first() = nullptr;
+ unique_ptr<__loop<_CharT> > __e2(
+ new __loop<_CharT>(__loop_count_, __s->first(), __e1.get(), __mexp_begin, __mexp_end, __greedy, __min, __max));
+ __s->first() = nullptr;
+ __e1.release();
+ __end_->first() = new __repeat_one_loop<_CharT>(__e2.get());
+ __end_ = __e2->second();
+ __s->first() = __e2.release();
+ ++__loop_count_;
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_char(value_type __c) {
+ if (flags() & icase)
+ __end_->first() = new __match_char_icase<_CharT, _Traits>(__traits_, __c, __end_->first());
+ else if (flags() & collate)
+ __end_->first() = new __match_char_collate<_CharT, _Traits>(__traits_, __c, __end_->first());
+ else
+ __end_->first() = new __match_char<_CharT>(__c, __end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_begin_marked_subexpression() {
+ if (!(__flags_ & nosubs)) {
+ __end_->first() = new __begin_marked_subexpression<_CharT>(++__marked_count_, __end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+ }
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_end_marked_subexpression(unsigned __sub) {
+ if (!(__flags_ & nosubs)) {
+ __end_->first() = new __end_marked_subexpression<_CharT>(__sub, __end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+ }
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_l_anchor() {
+ __end_->first() = new __l_anchor_multiline<_CharT>(__use_multiline(), __end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_r_anchor() {
+ __end_->first() = new __r_anchor_multiline<_CharT>(__use_multiline(), __end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_match_any() {
+ __end_->first() = new __match_any<_CharT>(__end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_match_any_but_newline() {
+ __end_->first() = new __match_any_but_newline<_CharT>(__end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_empty() {
+ __end_->first() = new __empty_state<_CharT>(__end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_word_boundary(bool __invert) {
+ __end_->first() = new __word_boundary<_CharT, _Traits>(__traits_, __invert, __end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_back_ref(int __i) {
+ if (flags() & icase)
+ __end_->first() = new __back_ref_icase<_CharT, _Traits>(__traits_, __i, __end_->first());
+ else if (flags() & collate)
+ __end_->first() = new __back_ref_collate<_CharT, _Traits>(__traits_, __i, __end_->first());
+ else
+ __end_->first() = new __back_ref<_CharT>(__i, __end_->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_alternation(__owns_one_state<_CharT>* __sa, __owns_one_state<_CharT>* __ea) {
+ __sa->first() = new __alternate<_CharT>(
+ static_cast<__owns_one_state<_CharT>*>(__sa->first()), static_cast<__owns_one_state<_CharT>*>(__ea->first()));
+ __ea->first() = nullptr;
+ __ea->first() = new __empty_state<_CharT>(__end_->first());
+ __end_->first() = nullptr;
+ __end_->first() = new __empty_non_own_state<_CharT>(__ea->first());
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__ea->first());
+}
+
+template <class _CharT, class _Traits>
+__bracket_expression<_CharT, _Traits>* basic_regex<_CharT, _Traits>::__start_matching_list(bool __negate) {
+ __bracket_expression<_CharT, _Traits>* __r = new __bracket_expression<_CharT, _Traits>(
+ __traits_, __end_->first(), __negate, __flags_ & icase, __flags_ & collate);
+ __end_->first() = __r;
+ __end_ = __r;
+ return __r;
+}
+
+template <class _CharT, class _Traits>
+void basic_regex<_CharT, _Traits>::__push_lookahead(const basic_regex& __exp, bool __invert, unsigned __mexp) {
+ __end_->first() = new __lookahead<_CharT, _Traits>(__exp, __invert, __end_->first(), __mexp);
+ __end_ = static_cast<__owns_one_state<_CharT>*>(__end_->first());
+}
+
+// sub_match
+
+typedef sub_match<const char*> csub_match;
+typedef sub_match<string::const_iterator> ssub_match;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+typedef sub_match<const wchar_t*> wcsub_match;
+typedef sub_match<wstring::const_iterator> wssub_match;
+#endif
+
+template <class _BidirectionalIterator>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_PREFERRED_NAME(csub_match)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wcsub_match)) _LIBCPP_PREFERRED_NAME(ssub_match)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wssub_match)) sub_match
+ : public pair<_BidirectionalIterator, _BidirectionalIterator> {
+public:
+ typedef _BidirectionalIterator iterator;
+ typedef typename iterator_traits<iterator>::value_type value_type;
+ typedef typename iterator_traits<iterator>::difference_type difference_type;
+ typedef basic_string<value_type> string_type;
+
+ bool matched;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR sub_match() : matched() {}
+
+ _LIBCPP_HIDE_FROM_ABI difference_type length() const {
+ return matched ? std::distance(this->first, this->second) : 0;
+ }
+ _LIBCPP_HIDE_FROM_ABI string_type str() const {
+ return matched ? string_type(this->first, this->second) : string_type();
+ }
+ _LIBCPP_HIDE_FROM_ABI operator string_type() const { return str(); }
+
+ _LIBCPP_HIDE_FROM_ABI int compare(const sub_match& __s) const { return str().compare(__s.str()); }
+ _LIBCPP_HIDE_FROM_ABI int compare(const string_type& __s) const { return str().compare(__s); }
+ _LIBCPP_HIDE_FROM_ABI int compare(const value_type* __s) const { return str().compare(__s); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(sub_match& __s) _NOEXCEPT_(__is_nothrow_swappable_v<_BidirectionalIterator>) {
+ this->pair<_BidirectionalIterator, _BidirectionalIterator>::swap(__s);
+ std::swap(matched, __s.matched);
+ }
+};
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const sub_match<_BiIter>& __x, const sub_match<_BiIter>& __y) {
+ return __x.compare(__y) == 0;
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _BiIter>
+using __sub_match_cat = compare_three_way_result_t<basic_string<typename iterator_traits<_BiIter>::value_type>>;
+
+template <class _BiIter>
+_LIBCPP_HIDE_FROM_ABI auto operator<=>(const sub_match<_BiIter>& __x, const sub_match<_BiIter>& __y) {
+ return static_cast<__sub_match_cat<_BiIter>>(__x.compare(__y) <=> 0);
+}
+#else // _LIBCPP_STD_VER >= 20
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const sub_match<_BiIter>& __x, const sub_match<_BiIter>& __y) {
+ return !(__x == __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const sub_match<_BiIter>& __x, const sub_match<_BiIter>& __y) {
+ return __x.compare(__y) < 0;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const sub_match<_BiIter>& __x, const sub_match<_BiIter>& __y) {
+ return !(__y < __x);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const sub_match<_BiIter>& __x, const sub_match<_BiIter>& __y) {
+ return !(__x < __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const sub_match<_BiIter>& __x, const sub_match<_BiIter>& __y) {
+ return __y < __x;
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __x,
+ const sub_match<_BiIter>& __y) {
+ return __y.compare(typename sub_match<_BiIter>::string_type(__x.data(), __x.size())) == 0;
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __x,
+ const sub_match<_BiIter>& __y) {
+ return !(__x == __y);
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __x,
+ const sub_match<_BiIter>& __y) {
+ return __y.compare(typename sub_match<_BiIter>::string_type(__x.data(), __x.size())) > 0;
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __x,
+ const sub_match<_BiIter>& __y) {
+ return __y < __x;
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __x,
+ const sub_match<_BiIter>& __y) {
+ return !(__x < __y);
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __x,
+ const sub_match<_BiIter>& __y) {
+ return !(__y < __x);
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const sub_match<_BiIter>& __x,
+ const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __y) {
+ return __x.compare(typename sub_match<_BiIter>::string_type(__y.data(), __y.size())) == 0;
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _BiIter, class _ST, class _SA>
+_LIBCPP_HIDE_FROM_ABI auto
+operator<=>(const sub_match<_BiIter>& __x,
+ const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __y) {
+ return static_cast<__sub_match_cat<_BiIter>>(
+ __x.compare(typename sub_match<_BiIter>::string_type(__y.data(), __y.size())) <=> 0);
+}
+#else // _LIBCPP_STD_VER >= 20
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const sub_match<_BiIter>& __x,
+ const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __y) {
+ return !(__x == __y);
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const sub_match<_BiIter>& __x,
+ const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __y) {
+ return __x.compare(typename sub_match<_BiIter>::string_type(__y.data(), __y.size())) < 0;
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const sub_match<_BiIter>& __x,
+ const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __y) {
+ return __y < __x;
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const sub_match<_BiIter>& __x,
+ const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __y) {
+ return !(__x < __y);
+}
+
+template <class _BiIter, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const sub_match<_BiIter>& __x,
+ const basic_string<typename iterator_traits<_BiIter>::value_type, _ST, _SA>& __y) {
+ return !(__y < __x);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(typename iterator_traits<_BiIter>::value_type const* __x, const sub_match<_BiIter>& __y) {
+ return __y.compare(__x) == 0;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(typename iterator_traits<_BiIter>::value_type const* __x, const sub_match<_BiIter>& __y) {
+ return !(__x == __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(typename iterator_traits<_BiIter>::value_type const* __x, const sub_match<_BiIter>& __y) {
+ return __y.compare(__x) > 0;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(typename iterator_traits<_BiIter>::value_type const* __x, const sub_match<_BiIter>& __y) {
+ return __y < __x;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(typename iterator_traits<_BiIter>::value_type const* __x, const sub_match<_BiIter>& __y) {
+ return !(__x < __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(typename iterator_traits<_BiIter>::value_type const* __x, const sub_match<_BiIter>& __y) {
+ return !(__y < __x);
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const* __y) {
+ return __x.compare(__y) == 0;
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _BiIter>
+_LIBCPP_HIDE_FROM_ABI auto
+operator<=>(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const* __y) {
+ return static_cast<__sub_match_cat<_BiIter>>(__x.compare(__y) <=> 0);
+}
+#else // _LIBCPP_STD_VER >= 20
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const* __y) {
+ return !(__x == __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const* __y) {
+ return __x.compare(__y) < 0;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const* __y) {
+ return __y < __x;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const* __y) {
+ return !(__x < __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const* __y) {
+ return !(__y < __x);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(typename iterator_traits<_BiIter>::value_type const& __x, const sub_match<_BiIter>& __y) {
+ typedef basic_string<typename iterator_traits<_BiIter>::value_type> string_type;
+ return __y.compare(string_type(1, __x)) == 0;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(typename iterator_traits<_BiIter>::value_type const& __x, const sub_match<_BiIter>& __y) {
+ return !(__x == __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(typename iterator_traits<_BiIter>::value_type const& __x, const sub_match<_BiIter>& __y) {
+ typedef basic_string<typename iterator_traits<_BiIter>::value_type> string_type;
+ return __y.compare(string_type(1, __x)) > 0;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(typename iterator_traits<_BiIter>::value_type const& __x, const sub_match<_BiIter>& __y) {
+ return __y < __x;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(typename iterator_traits<_BiIter>::value_type const& __x, const sub_match<_BiIter>& __y) {
+ return !(__x < __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(typename iterator_traits<_BiIter>::value_type const& __x, const sub_match<_BiIter>& __y) {
+ return !(__y < __x);
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const& __y) {
+ typedef basic_string<typename iterator_traits<_BiIter>::value_type> string_type;
+ return __x.compare(string_type(1, __y)) == 0;
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _BiIter>
+_LIBCPP_HIDE_FROM_ABI auto
+operator<=>(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const& __y) {
+ using string_type = basic_string<typename iterator_traits<_BiIter>::value_type>;
+ return static_cast<__sub_match_cat<_BiIter>>(__x.compare(string_type(1, __y)) <=> 0);
+}
+#else // _LIBCPP_STD_VER >= 20
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const& __y) {
+ return !(__x == __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const& __y) {
+ typedef basic_string<typename iterator_traits<_BiIter>::value_type> string_type;
+ return __x.compare(string_type(1, __y)) < 0;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const& __y) {
+ return __y < __x;
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const& __y) {
+ return !(__x < __y);
+}
+
+template <class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const sub_match<_BiIter>& __x, typename iterator_traits<_BiIter>::value_type const& __y) {
+ return !(__y < __x);
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _CharT, class _ST, class _BiIter>
+inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _ST>&
+operator<<(basic_ostream<_CharT, _ST>& __os, const sub_match<_BiIter>& __m) {
+ return __os << __m.str();
+}
+
+typedef match_results<const char*> cmatch;
+typedef match_results<string::const_iterator> smatch;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+typedef match_results<const wchar_t*> wcmatch;
+typedef match_results<wstring::const_iterator> wsmatch;
+#endif
+
+template <class _BidirectionalIterator, class _Allocator>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_PREFERRED_NAME(cmatch) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wcmatch))
+ _LIBCPP_PREFERRED_NAME(smatch) _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wsmatch)) match_results {
+public:
+ typedef _Allocator allocator_type;
+ typedef sub_match<_BidirectionalIterator> value_type;
+
+private:
+ typedef vector<value_type, allocator_type> __container_type;
+
+ __container_type __matches_;
+ value_type __unmatched_;
+ value_type __prefix_;
+ value_type __suffix_;
+ bool __ready_;
+
+public:
+ _BidirectionalIterator __position_start_;
+ typedef const value_type& const_reference;
+ typedef value_type& reference;
+ typedef typename __container_type::const_iterator const_iterator;
+ typedef const_iterator iterator;
+ typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type char_type;
+ typedef basic_string<char_type> string_type;
+
+ // construct/copy/destroy:
+#ifndef _LIBCPP_CXX03_LANG
+ match_results() : match_results(allocator_type()) {}
+ explicit match_results(const allocator_type& __a);
+#else
+ explicit match_results(const allocator_type& __a = allocator_type());
+#endif
+
+ // match_results(const match_results&) = default;
+ // match_results& operator=(const match_results&) = default;
+ // match_results(match_results&& __m) = default;
+ // match_results& operator=(match_results&& __m) = default;
+ // ~match_results() = default;
+
+ _LIBCPP_HIDE_FROM_ABI bool ready() const { return __ready_; }
+
+ // size:
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __matches_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __matches_.max_size(); }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return size() == 0; }
+
+ // element access:
+ _LIBCPP_HIDE_FROM_ABI difference_type length(size_type __sub = 0) const {
+ // If the match results are not ready, this will return `0`.
+ _LIBCPP_ASSERT_PEDANTIC(ready(), "match_results::length() called when not ready");
+ return (*this)[__sub].length();
+ }
+ _LIBCPP_HIDE_FROM_ABI difference_type position(size_type __sub = 0) const {
+ // If the match results are not ready, this will return the result of subtracting two default-constructed iterators
+ // (which is typically a well-defined operation).
+ _LIBCPP_ASSERT_PEDANTIC(ready(), "match_results::position() called when not ready");
+ return std::distance(__position_start_, (*this)[__sub].first);
+ }
+ _LIBCPP_HIDE_FROM_ABI string_type str(size_type __sub = 0) const {
+ // If the match results are not ready, this will return an empty string.
+ _LIBCPP_ASSERT_PEDANTIC(ready(), "match_results::str() called when not ready");
+ return (*this)[__sub].str();
+ }
+ _LIBCPP_HIDE_FROM_ABI const_reference operator[](size_type __n) const {
+ // If the match results are not ready, this call will be equivalent to calling this function with `__n >= size()`,
+ // returning an empty subrange.
+ _LIBCPP_ASSERT_PEDANTIC(ready(), "match_results::operator[]() called when not ready");
+ return __n < __matches_.size() ? __matches_[__n] : __unmatched_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_reference prefix() const {
+ // If the match results are not ready, this will return a default-constructed empty `__suffix_`.
+ _LIBCPP_ASSERT_PEDANTIC(ready(), "match_results::prefix() called when not ready");
+ return __prefix_;
+ }
+ _LIBCPP_HIDE_FROM_ABI const_reference suffix() const {
+ // If the match results are not ready, this will return a default-constructed empty `__suffix_`.
+ _LIBCPP_ASSERT_PEDANTIC(ready(), "match_results::suffix() called when not ready");
+ return __suffix_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const { return empty() ? __matches_.end() : __matches_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const { return __matches_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const { return empty() ? __matches_.end() : __matches_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const { return __matches_.end(); }
+
+ // format:
+ template <class _OutputIter>
+ _OutputIter format(_OutputIter __output_iter,
+ const char_type* __fmt_first,
+ const char_type* __fmt_last,
+ regex_constants::match_flag_type __flags = regex_constants::format_default) const;
+ template <class _OutputIter, class _ST, class _SA>
+ _LIBCPP_HIDE_FROM_ABI _OutputIter
+ format(_OutputIter __output_iter,
+ const basic_string<char_type, _ST, _SA>& __fmt,
+ regex_constants::match_flag_type __flags = regex_constants::format_default) const {
+ return format(__output_iter, __fmt.data(), __fmt.data() + __fmt.size(), __flags);
+ }
+ template <class _ST, class _SA>
+ _LIBCPP_HIDE_FROM_ABI basic_string<char_type, _ST, _SA>
+ format(const basic_string<char_type, _ST, _SA>& __fmt,
+ regex_constants::match_flag_type __flags = regex_constants::format_default) const {
+ basic_string<char_type, _ST, _SA> __r;
+ format(std::back_inserter(__r), __fmt.data(), __fmt.data() + __fmt.size(), __flags);
+ return __r;
+ }
+ _LIBCPP_HIDE_FROM_ABI string_type
+ format(const char_type* __fmt, regex_constants::match_flag_type __flags = regex_constants::format_default) const {
+ string_type __r;
+ format(std::back_inserter(__r), __fmt, __fmt + char_traits<char_type>::length(__fmt), __flags);
+ return __r;
+ }
+
+ // allocator:
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const { return __matches_.get_allocator(); }
+
+ // swap:
+ void swap(match_results& __m);
+
+ template <class _Bp, class _Ap>
+ _LIBCPP_HIDE_FROM_ABI void
+ __assign(_BidirectionalIterator __f,
+ _BidirectionalIterator __l,
+ const match_results<_Bp, _Ap>& __m,
+ bool __no_update_pos) {
+ _Bp __mf = __m.prefix().first;
+ __matches_.resize(__m.size());
+ for (size_type __i = 0; __i < __matches_.size(); ++__i) {
+ __matches_[__i].first = std::next(__f, std::distance(__mf, __m[__i].first));
+ __matches_[__i].second = std::next(__f, std::distance(__mf, __m[__i].second));
+ __matches_[__i].matched = __m[__i].matched;
+ }
+ __unmatched_.first = __l;
+ __unmatched_.second = __l;
+ __unmatched_.matched = false;
+ __prefix_.first = std::next(__f, std::distance(__mf, __m.prefix().first));
+ __prefix_.second = std::next(__f, std::distance(__mf, __m.prefix().second));
+ __prefix_.matched = __m.prefix().matched;
+ __suffix_.first = std::next(__f, std::distance(__mf, __m.suffix().first));
+ __suffix_.second = std::next(__f, std::distance(__mf, __m.suffix().second));
+ __suffix_.matched = __m.suffix().matched;
+ if (!__no_update_pos)
+ __position_start_ = __prefix_.first;
+ __ready_ = __m.ready();
+ }
+
+private:
+ void __init(unsigned __s, _BidirectionalIterator __f, _BidirectionalIterator __l, bool __no_update_pos = false);
+
+ template <class, class>
+ friend class basic_regex;
+
+ template <class _Bp, class _Ap, class _Cp, class _Tp>
+ friend bool
+ regex_match(_Bp, _Bp, match_results<_Bp, _Ap>&, const basic_regex<_Cp, _Tp>&, regex_constants::match_flag_type);
+
+ template <class _Bp, class _Ap>
+ friend bool operator==(const match_results<_Bp, _Ap>&, const match_results<_Bp, _Ap>&);
+
+ template <class, class>
+ friend class __lookahead;
+
+ template <class, class, class>
+ friend class regex_iterator;
+};
+
+template <class _BidirectionalIterator, class _Allocator>
+match_results<_BidirectionalIterator, _Allocator>::match_results(const allocator_type& __a)
+ : __matches_(__a), __unmatched_(), __prefix_(), __suffix_(), __ready_(false), __position_start_() {}
+
+template <class _BidirectionalIterator, class _Allocator>
+void match_results<_BidirectionalIterator, _Allocator>::__init(
+ unsigned __s, _BidirectionalIterator __f, _BidirectionalIterator __l, bool __no_update_pos) {
+ __unmatched_.first = __l;
+ __unmatched_.second = __l;
+ __unmatched_.matched = false;
+ __matches_.assign(__s, __unmatched_);
+ __prefix_.first = __f;
+ __prefix_.second = __f;
+ __prefix_.matched = false;
+ __suffix_ = __unmatched_;
+ if (!__no_update_pos)
+ __position_start_ = __prefix_.first;
+ __ready_ = true;
+}
+
+template <class _BidirectionalIterator, class _Allocator>
+template <class _OutputIter>
+_OutputIter match_results<_BidirectionalIterator, _Allocator>::format(
+ _OutputIter __output_iter,
+ const char_type* __fmt_first,
+ const char_type* __fmt_last,
+ regex_constants::match_flag_type __flags) const {
+ // Note: this duplicates a check in `vector::operator[]` but provides a better error message.
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(ready(), "match_results::format() called when not ready");
+ if (__flags & regex_constants::format_sed) {
+ for (; __fmt_first != __fmt_last; ++__fmt_first) {
+ if (*__fmt_first == '&')
+ __output_iter = std::copy(__matches_[0].first, __matches_[0].second, __output_iter);
+ else if (*__fmt_first == '\\' && __fmt_first + 1 != __fmt_last) {
+ ++__fmt_first;
+ if ('0' <= *__fmt_first && *__fmt_first <= '9') {
+ size_t __i = *__fmt_first - '0';
+ __output_iter = std::copy((*this)[__i].first, (*this)[__i].second, __output_iter);
+ } else {
+ *__output_iter = *__fmt_first;
+ ++__output_iter;
+ }
+ } else {
+ *__output_iter = *__fmt_first;
+ ++__output_iter;
+ }
+ }
+ } else {
+ for (; __fmt_first != __fmt_last; ++__fmt_first) {
+ if (*__fmt_first == '$' && __fmt_first + 1 != __fmt_last) {
+ switch (__fmt_first[1]) {
+ case '$':
+ *__output_iter = *++__fmt_first;
+ ++__output_iter;
+ break;
+ case '&':
+ ++__fmt_first;
+ __output_iter = std::copy(__matches_[0].first, __matches_[0].second, __output_iter);
+ break;
+ case '`':
+ ++__fmt_first;
+ __output_iter = std::copy(__prefix_.first, __prefix_.second, __output_iter);
+ break;
+ case '\'':
+ ++__fmt_first;
+ __output_iter = std::copy(__suffix_.first, __suffix_.second, __output_iter);
+ break;
+ default:
+ if ('0' <= __fmt_first[1] && __fmt_first[1] <= '9') {
+ ++__fmt_first;
+ size_t __idx = *__fmt_first - '0';
+ if (__fmt_first + 1 != __fmt_last && '0' <= __fmt_first[1] && __fmt_first[1] <= '9') {
+ ++__fmt_first;
+ if (__idx >= numeric_limits<size_t>::max() / 10)
+ __throw_regex_error<regex_constants::error_escape>();
+ __idx = 10 * __idx + *__fmt_first - '0';
+ }
+ __output_iter = std::copy((*this)[__idx].first, (*this)[__idx].second, __output_iter);
+ } else {
+ *__output_iter = *__fmt_first;
+ ++__output_iter;
+ }
+ break;
+ }
+ } else {
+ *__output_iter = *__fmt_first;
+ ++__output_iter;
+ }
+ }
+ }
+ return __output_iter;
+}
+
+template <class _BidirectionalIterator, class _Allocator>
+void match_results<_BidirectionalIterator, _Allocator>::swap(match_results& __m) {
+ using std::swap;
+ swap(__matches_, __m.__matches_);
+ swap(__unmatched_, __m.__unmatched_);
+ swap(__prefix_, __m.__prefix_);
+ swap(__suffix_, __m.__suffix_);
+ swap(__position_start_, __m.__position_start_);
+ swap(__ready_, __m.__ready_);
+}
+
+template <class _BidirectionalIterator, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const match_results<_BidirectionalIterator, _Allocator>& __x,
+ const match_results<_BidirectionalIterator, _Allocator>& __y) {
+ if (__x.__ready_ != __y.__ready_)
+ return false;
+ if (!__x.__ready_)
+ return true;
+ return __x.__matches_ == __y.__matches_ && __x.__prefix_ == __y.__prefix_ && __x.__suffix_ == __y.__suffix_;
+}
+
+#if _LIBCPP_STD_VER < 20
+template <class _BidirectionalIterator, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const match_results<_BidirectionalIterator, _Allocator>& __x,
+ const match_results<_BidirectionalIterator, _Allocator>& __y) {
+ return !(__x == __y);
+}
+#endif
+
+template <class _BidirectionalIterator, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(match_results<_BidirectionalIterator, _Allocator>& __x, match_results<_BidirectionalIterator, _Allocator>& __y) {
+ __x.swap(__y);
+}
+
+// regex_search
+
+template <class _CharT, class _Traits>
+template <class _Allocator>
+bool basic_regex<_CharT, _Traits>::__match_at_start_ecma(
+ const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags,
+ bool __at_first) const {
+ vector<__state> __states;
+ __node* __st = __start_.get();
+ if (__st) {
+ sub_match<const _CharT*> __unmatched;
+ __unmatched.first = __last;
+ __unmatched.second = __last;
+ __unmatched.matched = false;
+
+ __states.push_back(__state());
+ __states.back().__do_ = 0;
+ __states.back().__first_ = __first;
+ __states.back().__current_ = __first;
+ __states.back().__last_ = __last;
+ __states.back().__sub_matches_.resize(mark_count(), __unmatched);
+ __states.back().__loop_data_.resize(__loop_count());
+ __states.back().__node_ = __st;
+ __states.back().__flags_ = __flags;
+ __states.back().__at_first_ = __at_first;
+ int __counter = 0;
+ int __length = __last - __first;
+ do {
+ ++__counter;
+ if (__counter % _LIBCPP_REGEX_COMPLEXITY_FACTOR == 0 && __counter / _LIBCPP_REGEX_COMPLEXITY_FACTOR >= __length)
+ __throw_regex_error<regex_constants::error_complexity>();
+ __state& __s = __states.back();
+ if (__s.__node_)
+ __s.__node_->__exec(__s);
+ switch (__s.__do_) {
+ case __state::__end_state:
+ if ((__flags & regex_constants::match_not_null) && __s.__current_ == __first) {
+ __states.pop_back();
+ break;
+ }
+ if ((__flags & regex_constants::__full_match) && __s.__current_ != __last) {
+ __states.pop_back();
+ break;
+ }
+ __m.__matches_[0].first = __first;
+ __m.__matches_[0].second = std::next(__first, __s.__current_ - __first);
+ __m.__matches_[0].matched = true;
+ for (unsigned __i = 0; __i < __s.__sub_matches_.size(); ++__i)
+ __m.__matches_[__i + 1] = __s.__sub_matches_[__i];
+ return true;
+ case __state::__accept_and_consume:
+ case __state::__repeat:
+ case __state::__accept_but_not_consume:
+ break;
+ case __state::__split: {
+ __state __snext = __s;
+ __s.__node_->__exec_split(true, __s);
+ __snext.__node_->__exec_split(false, __snext);
+ __states.push_back(std::move(__snext));
+ } break;
+ case __state::__reject:
+ __states.pop_back();
+ break;
+ default:
+ __throw_regex_error<regex_constants::__re_err_unknown>();
+ break;
+ }
+ } while (!__states.empty());
+ }
+ return false;
+}
+
+template <class _CharT, class _Traits>
+template <class _Allocator>
+bool basic_regex<_CharT, _Traits>::__match_at_start_posix_nosubs(
+ const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags,
+ bool __at_first) const {
+ deque<__state> __states;
+ ptrdiff_t __highest_j = 0;
+ ptrdiff_t __np = std::distance(__first, __last);
+ __node* __st = __start_.get();
+ if (__st) {
+ __states.push_back(__state());
+ __states.back().__do_ = 0;
+ __states.back().__first_ = __first;
+ __states.back().__current_ = __first;
+ __states.back().__last_ = __last;
+ __states.back().__loop_data_.resize(__loop_count());
+ __states.back().__node_ = __st;
+ __states.back().__flags_ = __flags;
+ __states.back().__at_first_ = __at_first;
+ bool __matched = false;
+ int __counter = 0;
+ int __length = __last - __first;
+ do {
+ ++__counter;
+ if (__counter % _LIBCPP_REGEX_COMPLEXITY_FACTOR == 0 && __counter / _LIBCPP_REGEX_COMPLEXITY_FACTOR >= __length)
+ __throw_regex_error<regex_constants::error_complexity>();
+ __state& __s = __states.back();
+ if (__s.__node_)
+ __s.__node_->__exec(__s);
+ switch (__s.__do_) {
+ case __state::__end_state:
+ if ((__flags & regex_constants::match_not_null) && __s.__current_ == __first) {
+ __states.pop_back();
+ break;
+ }
+ if ((__flags & regex_constants::__full_match) && __s.__current_ != __last) {
+ __states.pop_back();
+ break;
+ }
+ if (!__matched || __highest_j < __s.__current_ - __s.__first_)
+ __highest_j = __s.__current_ - __s.__first_;
+ __matched = true;
+ if (__highest_j == __np)
+ __states.clear();
+ else
+ __states.pop_back();
+ break;
+ case __state::__consume_input:
+ break;
+ case __state::__accept_and_consume:
+ __states.push_front(std::move(__s));
+ __states.pop_back();
+ break;
+ case __state::__repeat:
+ case __state::__accept_but_not_consume:
+ break;
+ case __state::__split: {
+ __state __snext = __s;
+ __s.__node_->__exec_split(true, __s);
+ __snext.__node_->__exec_split(false, __snext);
+ __states.push_back(std::move(__snext));
+ } break;
+ case __state::__reject:
+ __states.pop_back();
+ break;
+ default:
+ __throw_regex_error<regex_constants::__re_err_unknown>();
+ break;
+ }
+ } while (!__states.empty());
+ if (__matched) {
+ __m.__matches_[0].first = __first;
+ __m.__matches_[0].second = std::next(__first, __highest_j);
+ __m.__matches_[0].matched = true;
+ return true;
+ }
+ }
+ return false;
+}
+
+template <class _CharT, class _Traits>
+template <class _Allocator>
+bool basic_regex<_CharT, _Traits>::__match_at_start_posix_subs(
+ const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags,
+ bool __at_first) const {
+ vector<__state> __states;
+ __state __best_state;
+ ptrdiff_t __highest_j = 0;
+ ptrdiff_t __np = std::distance(__first, __last);
+ __node* __st = __start_.get();
+ if (__st) {
+ sub_match<const _CharT*> __unmatched;
+ __unmatched.first = __last;
+ __unmatched.second = __last;
+ __unmatched.matched = false;
+
+ __states.push_back(__state());
+ __states.back().__do_ = 0;
+ __states.back().__first_ = __first;
+ __states.back().__current_ = __first;
+ __states.back().__last_ = __last;
+ __states.back().__sub_matches_.resize(mark_count(), __unmatched);
+ __states.back().__loop_data_.resize(__loop_count());
+ __states.back().__node_ = __st;
+ __states.back().__flags_ = __flags;
+ __states.back().__at_first_ = __at_first;
+ bool __matched = false;
+ int __counter = 0;
+ int __length = __last - __first;
+ do {
+ ++__counter;
+ if (__counter % _LIBCPP_REGEX_COMPLEXITY_FACTOR == 0 && __counter / _LIBCPP_REGEX_COMPLEXITY_FACTOR >= __length)
+ __throw_regex_error<regex_constants::error_complexity>();
+ __state& __s = __states.back();
+ if (__s.__node_)
+ __s.__node_->__exec(__s);
+ switch (__s.__do_) {
+ case __state::__end_state:
+ if ((__flags & regex_constants::match_not_null) && __s.__current_ == __first) {
+ __states.pop_back();
+ break;
+ }
+ if ((__flags & regex_constants::__full_match) && __s.__current_ != __last) {
+ __states.pop_back();
+ break;
+ }
+ if (!__matched || __highest_j < __s.__current_ - __s.__first_) {
+ __highest_j = __s.__current_ - __s.__first_;
+ __best_state = __s;
+ }
+ __matched = true;
+ if (__highest_j == __np)
+ __states.clear();
+ else
+ __states.pop_back();
+ break;
+ case __state::__accept_and_consume:
+ case __state::__repeat:
+ case __state::__accept_but_not_consume:
+ break;
+ case __state::__split: {
+ __state __snext = __s;
+ __s.__node_->__exec_split(true, __s);
+ __snext.__node_->__exec_split(false, __snext);
+ __states.push_back(std::move(__snext));
+ } break;
+ case __state::__reject:
+ __states.pop_back();
+ break;
+ default:
+ __throw_regex_error<regex_constants::__re_err_unknown>();
+ break;
+ }
+ } while (!__states.empty());
+ if (__matched) {
+ __m.__matches_[0].first = __first;
+ __m.__matches_[0].second = std::next(__first, __highest_j);
+ __m.__matches_[0].matched = true;
+ for (unsigned __i = 0; __i < __best_state.__sub_matches_.size(); ++__i)
+ __m.__matches_[__i + 1] = __best_state.__sub_matches_[__i];
+ return true;
+ }
+ }
+ return false;
+}
+
+template <class _CharT, class _Traits>
+template <class _Allocator>
+bool basic_regex<_CharT, _Traits>::__match_at_start(
+ const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags,
+ bool __at_first) const {
+ if (__get_grammar(__flags_) == ECMAScript)
+ return __match_at_start_ecma(__first, __last, __m, __flags, __at_first);
+ if (mark_count() == 0)
+ return __match_at_start_posix_nosubs(__first, __last, __m, __flags, __at_first);
+ return __match_at_start_posix_subs(__first, __last, __m, __flags, __at_first);
+}
+
+template <class _CharT, class _Traits>
+template <class _Allocator>
+bool basic_regex<_CharT, _Traits>::__search(
+ const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ regex_constants::match_flag_type __flags) const {
+ if (__flags & regex_constants::match_prev_avail)
+ __flags &= ~(regex_constants::match_not_bol | regex_constants::match_not_bow);
+
+ __m.__init(1 + mark_count(), __first, __last, __flags & regex_constants::__no_update_pos);
+ if (__match_at_start(__first, __last, __m, __flags, !(__flags & regex_constants::__no_update_pos))) {
+ __m.__prefix_.second = __m[0].first;
+ __m.__prefix_.matched = __m.__prefix_.first != __m.__prefix_.second;
+ __m.__suffix_.first = __m[0].second;
+ __m.__suffix_.matched = __m.__suffix_.first != __m.__suffix_.second;
+ return true;
+ }
+ if (__first != __last && !(__flags & regex_constants::match_continuous)) {
+ __flags |= regex_constants::match_prev_avail;
+ for (++__first; __first != __last; ++__first) {
+ __m.__matches_.assign(__m.size(), __m.__unmatched_);
+ if (__match_at_start(__first, __last, __m, __flags, false)) {
+ __m.__prefix_.second = __m[0].first;
+ __m.__prefix_.matched = __m.__prefix_.first != __m.__prefix_.second;
+ __m.__suffix_.first = __m[0].second;
+ __m.__suffix_.matched = __m.__suffix_.first != __m.__suffix_.second;
+ return true;
+ }
+ __m.__matches_.assign(__m.size(), __m.__unmatched_);
+ }
+ __m.__matches_.assign(__m.size(), __m.__unmatched_);
+ if (__match_at_start(__first, __last, __m, __flags, false)) {
+ __m.__prefix_.second = __m[0].first;
+ __m.__prefix_.matched = __m.__prefix_.first != __m.__prefix_.second;
+ __m.__suffix_.first = __m[0].second;
+ __m.__suffix_.matched = __m.__suffix_.first != __m.__suffix_.second;
+ return true;
+ }
+ }
+ __m.__matches_.clear();
+ return false;
+}
+
+template <class _BidirectionalIterator, class _Allocator, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(_BidirectionalIterator __first,
+ _BidirectionalIterator __last,
+ match_results<_BidirectionalIterator, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ int __offset = (__flags & regex_constants::match_prev_avail) ? 1 : 0;
+ basic_string<_CharT> __s(std::prev(__first, __offset), __last);
+ match_results<const _CharT*> __mc;
+ bool __r = __e.__search(__s.data() + __offset, __s.data() + __s.size(), __mc, __flags);
+ __m.__assign(__first, __last, __mc, __flags & regex_constants::__no_update_pos);
+ return __r;
+}
+
+template <class _Iter, class _Allocator, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(__wrap_iter<_Iter> __first,
+ __wrap_iter<_Iter> __last,
+ match_results<__wrap_iter<_Iter>, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ match_results<const _CharT*> __mc;
+ bool __r = __e.__search(__first.base(), __last.base(), __mc, __flags);
+ __m.__assign(__first, __last, __mc, __flags & regex_constants::__no_update_pos);
+ return __r;
+}
+
+template <class _Allocator, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(const _CharT* __first,
+ const _CharT* __last,
+ match_results<const _CharT*, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ return __e.__search(__first, __last, __m, __flags);
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(_BidirectionalIterator __first,
+ _BidirectionalIterator __last,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ basic_string<_CharT> __s(__first, __last);
+ match_results<const _CharT*> __mc;
+ return __e.__search(__s.data(), __s.data() + __s.size(), __mc, __flags);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(const _CharT* __first,
+ const _CharT* __last,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ match_results<const _CharT*> __mc;
+ return __e.__search(__first, __last, __mc, __flags);
+}
+
+template <class _CharT, class _Allocator, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(const _CharT* __str,
+ match_results<const _CharT*, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ return __e.__search(__str, __str + _Traits::length(__str), __m, __flags);
+}
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(const _CharT* __str,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ match_results<const _CharT*> __m;
+ return std::regex_search(__str, __m, __e, __flags);
+}
+
+template <class _ST, class _SA, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(const basic_string<_CharT, _ST, _SA>& __s,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ match_results<const _CharT*> __mc;
+ return __e.__search(__s.data(), __s.data() + __s.size(), __mc, __flags);
+}
+
+template <class _ST, class _SA, class _Allocator, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_search(const basic_string<_CharT, _ST, _SA>& __s,
+ match_results<typename basic_string<_CharT, _ST, _SA>::const_iterator, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ match_results<const _CharT*> __mc;
+ bool __r = __e.__search(__s.data(), __s.data() + __s.size(), __mc, __flags);
+ __m.__assign(__s.begin(), __s.end(), __mc, __flags & regex_constants::__no_update_pos);
+ return __r;
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _ST, class _SA, class _Ap, class _Cp, class _Tp>
+bool regex_search(const basic_string<_Cp, _ST, _SA>&& __s,
+ match_results<typename basic_string<_Cp, _ST, _SA>::const_iterator, _Ap>&,
+ const basic_regex<_Cp, _Tp>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) = delete;
+#endif
+
+// regex_match
+
+template <class _BidirectionalIterator, class _Allocator, class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI bool
+regex_match(_BidirectionalIterator __first,
+ _BidirectionalIterator __last,
+ match_results<_BidirectionalIterator, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ bool __r = std::regex_search(
+ __first, __last, __m, __e, __flags | regex_constants::match_continuous | regex_constants::__full_match);
+ if (__r) {
+ __r = !__m.suffix().matched;
+ if (!__r)
+ __m.__matches_.clear();
+ }
+ return __r;
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_match(_BidirectionalIterator __first,
+ _BidirectionalIterator __last,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ match_results<_BidirectionalIterator> __m;
+ return std::regex_match(__first, __last, __m, __e, __flags);
+}
+
+template <class _CharT, class _Allocator, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_match(const _CharT* __str,
+ match_results<const _CharT*, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ return std::regex_match(__str, __str + _Traits::length(__str), __m, __e, __flags);
+}
+
+template <class _ST, class _SA, class _Allocator, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_match(const basic_string<_CharT, _ST, _SA>& __s,
+ match_results<typename basic_string<_CharT, _ST, _SA>::const_iterator, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ return std::regex_match(__s.begin(), __s.end(), __m, __e, __flags);
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _ST, class _SA, class _Allocator, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_match(const basic_string<_CharT, _ST, _SA>&& __s,
+ match_results<typename basic_string<_CharT, _ST, _SA>::const_iterator, _Allocator>& __m,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) = delete;
+#endif
+
+template <class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_match(const _CharT* __str,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ return std::regex_match(__str, __str + _Traits::length(__str), __e, __flags);
+}
+
+template <class _ST, class _SA, class _CharT, class _Traits>
+inline _LIBCPP_HIDE_FROM_ABI bool
+regex_match(const basic_string<_CharT, _ST, _SA>& __s,
+ const basic_regex<_CharT, _Traits>& __e,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ return std::regex_match(__s.begin(), __s.end(), __e, __flags);
+}
+
+// regex_iterator
+
+template <class _BidirectionalIterator,
+ class _CharT = typename iterator_traits<_BidirectionalIterator>::value_type,
+ class _Traits = regex_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS regex_iterator;
+
+typedef regex_iterator<const char*> cregex_iterator;
+typedef regex_iterator<string::const_iterator> sregex_iterator;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+typedef regex_iterator<const wchar_t*> wcregex_iterator;
+typedef regex_iterator<wstring::const_iterator> wsregex_iterator;
+#endif
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_PREFERRED_NAME(cregex_iterator)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wcregex_iterator)) _LIBCPP_PREFERRED_NAME(sregex_iterator)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wsregex_iterator)) regex_iterator {
+public:
+ typedef basic_regex<_CharT, _Traits> regex_type;
+ typedef match_results<_BidirectionalIterator> value_type;
+ typedef ptrdiff_t difference_type;
+ typedef const value_type* pointer;
+ typedef const value_type& reference;
+ typedef forward_iterator_tag iterator_category;
+#if _LIBCPP_STD_VER >= 20
+ typedef input_iterator_tag iterator_concept;
+#endif
+
+private:
+ _BidirectionalIterator __begin_;
+ _BidirectionalIterator __end_;
+ const regex_type* __pregex_;
+ regex_constants::match_flag_type __flags_;
+ value_type __match_;
+
+public:
+ regex_iterator();
+ regex_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ regex_constants::match_flag_type __m = regex_constants::match_default);
+#if _LIBCPP_STD_VER >= 14
+ regex_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type&& __re,
+ regex_constants::match_flag_type __m = regex_constants::match_default) = delete;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI bool operator==(const regex_iterator& __x) const;
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool operator==(default_sentinel_t) const { return *this == regex_iterator(); }
+#endif
+#if _LIBCPP_STD_VER < 20
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(const regex_iterator& __x) const { return !(*this == __x); }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __match_; }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return std::addressof(__match_); }
+
+ regex_iterator& operator++();
+ _LIBCPP_HIDE_FROM_ABI regex_iterator operator++(int) {
+ regex_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+};
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_iterator<_BidirectionalIterator, _CharT, _Traits>::regex_iterator()
+ : __begin_(), __end_(), __pregex_(nullptr), __flags_(), __match_() {}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_iterator<_BidirectionalIterator, _CharT, _Traits>::regex_iterator(
+ _BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ regex_constants::match_flag_type __m)
+ : __begin_(__a), __end_(__b), __pregex_(std::addressof(__re)), __flags_(__m) {
+ std::regex_search(__begin_, __end_, __match_, *__pregex_, __flags_);
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+bool regex_iterator<_BidirectionalIterator, _CharT, _Traits>::operator==(const regex_iterator& __x) const {
+ if (__match_.empty() && __x.__match_.empty())
+ return true;
+ if (__match_.empty() || __x.__match_.empty())
+ return false;
+ return __begin_ == __x.__begin_ && __end_ == __x.__end_ && __pregex_ == __x.__pregex_ && __flags_ == __x.__flags_ &&
+ __match_[0] == __x.__match_[0];
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_iterator<_BidirectionalIterator, _CharT, _Traits>&
+regex_iterator<_BidirectionalIterator, _CharT, _Traits>::operator++() {
+ __flags_ |= regex_constants::__no_update_pos;
+ _BidirectionalIterator __start = __match_[0].second;
+ _BidirectionalIterator __prefix_start = __start;
+
+ if (__match_[0].first == __match_[0].second) {
+ if (__start == __end_) {
+ __match_ = value_type();
+ return *this;
+ } else if (std::regex_search(__start,
+ __end_,
+ __match_,
+ *__pregex_,
+ __flags_ | regex_constants::match_not_null | regex_constants::match_continuous))
+ return *this;
+ else
+ ++__start;
+ }
+
+ __flags_ |= regex_constants::match_prev_avail;
+ if (!std::regex_search(__start, __end_, __match_, *__pregex_, __flags_)) {
+ __match_ = value_type();
+
+ } else {
+ // The Standard mandates that if `regex_search` returns true ([re.regiter.incr]), "`match.prefix().first` shall be
+ // equal to the previous value of `match[0].second`... It is unspecified how the implementation makes these
+ // adjustments." The adjustment is necessary if we incremented `__start` above (the branch that deals with
+ // zero-length matches).
+ auto& __prefix = __match_.__prefix_;
+ __prefix.first = __prefix_start;
+ __prefix.matched = __prefix.first != __prefix.second;
+ }
+
+ return *this;
+}
+
+// regex_token_iterator
+
+template <class _BidirectionalIterator,
+ class _CharT = typename iterator_traits<_BidirectionalIterator>::value_type,
+ class _Traits = regex_traits<_CharT> >
+class _LIBCPP_TEMPLATE_VIS regex_token_iterator;
+
+typedef regex_token_iterator<const char*> cregex_token_iterator;
+typedef regex_token_iterator<string::const_iterator> sregex_token_iterator;
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+typedef regex_token_iterator<const wchar_t*> wcregex_token_iterator;
+typedef regex_token_iterator<wstring::const_iterator> wsregex_token_iterator;
+#endif
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_PREFERRED_NAME(cregex_token_iterator)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wcregex_token_iterator))
+ _LIBCPP_PREFERRED_NAME(sregex_token_iterator)
+ _LIBCPP_IF_WIDE_CHARACTERS(_LIBCPP_PREFERRED_NAME(wsregex_token_iterator)) regex_token_iterator {
+public:
+ typedef basic_regex<_CharT, _Traits> regex_type;
+ typedef sub_match<_BidirectionalIterator> value_type;
+ typedef ptrdiff_t difference_type;
+ typedef const value_type* pointer;
+ typedef const value_type& reference;
+ typedef forward_iterator_tag iterator_category;
+#if _LIBCPP_STD_VER >= 20
+ typedef input_iterator_tag iterator_concept;
+#endif
+
+private:
+ typedef regex_iterator<_BidirectionalIterator, _CharT, _Traits> _Position;
+
+ _Position __position_;
+ const value_type* __result_;
+ value_type __suffix_;
+ ptrdiff_t __n_;
+ vector<int> __subs_;
+
+public:
+ regex_token_iterator();
+ regex_token_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ int __submatch = 0,
+ regex_constants::match_flag_type __m = regex_constants::match_default);
+#if _LIBCPP_STD_VER >= 14
+ regex_token_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type&& __re,
+ int __submatch = 0,
+ regex_constants::match_flag_type __m = regex_constants::match_default) = delete;
+#endif
+
+ regex_token_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ const vector<int>& __submatches,
+ regex_constants::match_flag_type __m = regex_constants::match_default);
+#if _LIBCPP_STD_VER >= 14
+ regex_token_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type&& __re,
+ const vector<int>& __submatches,
+ regex_constants::match_flag_type __m = regex_constants::match_default) = delete;
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ regex_token_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ initializer_list<int> __submatches,
+ regex_constants::match_flag_type __m = regex_constants::match_default);
+
+# if _LIBCPP_STD_VER >= 14
+ regex_token_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type&& __re,
+ initializer_list<int> __submatches,
+ regex_constants::match_flag_type __m = regex_constants::match_default) = delete;
+# endif
+#endif // _LIBCPP_CXX03_LANG
+ template <size_t _Np>
+ regex_token_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ const int (&__submatches)[_Np],
+ regex_constants::match_flag_type __m = regex_constants::match_default);
+#if _LIBCPP_STD_VER >= 14
+ template <size_t _Np>
+ regex_token_iterator(_BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type&& __re,
+ const int (&__submatches)[_Np],
+ regex_constants::match_flag_type __m = regex_constants::match_default) = delete;
+#endif
+
+ regex_token_iterator(const regex_token_iterator&);
+ regex_token_iterator& operator=(const regex_token_iterator&);
+
+ _LIBCPP_HIDE_FROM_ABI bool operator==(const regex_token_iterator& __x) const;
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDE_FROM_ABI bool operator==(default_sentinel_t) const {
+ return *this == regex_token_iterator();
+ }
+#endif
+#if _LIBCPP_STD_VER < 20
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(const regex_token_iterator& __x) const { return !(*this == __x); }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI const value_type& operator*() const { return *__result_; }
+ _LIBCPP_HIDE_FROM_ABI const value_type* operator->() const { return __result_; }
+
+ regex_token_iterator& operator++();
+ _LIBCPP_HIDE_FROM_ABI regex_token_iterator operator++(int) {
+ regex_token_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+private:
+ void __init(_BidirectionalIterator __a, _BidirectionalIterator __b);
+ void __establish_result() {
+ if (__subs_[__n_] == -1)
+ __result_ = &__position_->prefix();
+ else
+ __result_ = &(*__position_)[__subs_[__n_]];
+ }
+};
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::regex_token_iterator()
+ : __result_(nullptr), __suffix_(), __n_(0) {}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+void regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::__init(
+ _BidirectionalIterator __a, _BidirectionalIterator __b) {
+ if (__position_ != _Position())
+ __establish_result();
+ else if (__subs_[__n_] == -1) {
+ __suffix_.matched = true;
+ __suffix_.first = __a;
+ __suffix_.second = __b;
+ __result_ = &__suffix_;
+ } else
+ __result_ = nullptr;
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::regex_token_iterator(
+ _BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ int __submatch,
+ regex_constants::match_flag_type __m)
+ : __position_(__a, __b, __re, __m), __n_(0), __subs_(1, __submatch) {
+ __init(__a, __b);
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::regex_token_iterator(
+ _BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ const vector<int>& __submatches,
+ regex_constants::match_flag_type __m)
+ : __position_(__a, __b, __re, __m), __n_(0), __subs_(__submatches) {
+ __init(__a, __b);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::regex_token_iterator(
+ _BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ initializer_list<int> __submatches,
+ regex_constants::match_flag_type __m)
+ : __position_(__a, __b, __re, __m), __n_(0), __subs_(__submatches) {
+ __init(__a, __b);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+template <size_t _Np>
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::regex_token_iterator(
+ _BidirectionalIterator __a,
+ _BidirectionalIterator __b,
+ const regex_type& __re,
+ const int (&__submatches)[_Np],
+ regex_constants::match_flag_type __m)
+ : __position_(__a, __b, __re, __m), __n_(0), __subs_(begin(__submatches), end(__submatches)) {
+ __init(__a, __b);
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::regex_token_iterator(const regex_token_iterator& __x)
+ : __position_(__x.__position_),
+ __result_(__x.__result_),
+ __suffix_(__x.__suffix_),
+ __n_(__x.__n_),
+ __subs_(__x.__subs_) {
+ if (__x.__result_ == &__x.__suffix_)
+ __result_ = &__suffix_;
+ else if (__result_ != nullptr)
+ __establish_result();
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>&
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::operator=(const regex_token_iterator& __x) {
+ if (this != &__x) {
+ __position_ = __x.__position_;
+ if (__x.__result_ == &__x.__suffix_)
+ __result_ = &__suffix_;
+ else
+ __result_ = __x.__result_;
+ __suffix_ = __x.__suffix_;
+ __n_ = __x.__n_;
+ __subs_ = __x.__subs_;
+
+ if (__result_ != nullptr && __result_ != &__suffix_)
+ __establish_result();
+ }
+ return *this;
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+bool regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::operator==(const regex_token_iterator& __x) const {
+ if (__result_ == nullptr && __x.__result_ == nullptr)
+ return true;
+ if (__result_ == &__suffix_ && __x.__result_ == &__x.__suffix_ && __suffix_ == __x.__suffix_)
+ return true;
+ if (__result_ == nullptr || __x.__result_ == nullptr)
+ return false;
+ if (__result_ == &__suffix_ || __x.__result_ == &__x.__suffix_)
+ return false;
+ return __position_ == __x.__position_ && __n_ == __x.__n_ && __subs_ == __x.__subs_;
+}
+
+template <class _BidirectionalIterator, class _CharT, class _Traits>
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>&
+regex_token_iterator<_BidirectionalIterator, _CharT, _Traits>::operator++() {
+ _Position __prev = __position_;
+ if (__result_ == &__suffix_)
+ __result_ = nullptr;
+ else if (static_cast<size_t>(__n_ + 1) < __subs_.size()) {
+ ++__n_;
+ __establish_result();
+ } else {
+ __n_ = 0;
+ ++__position_;
+ if (__position_ != _Position())
+ __establish_result();
+ else {
+ if (std::find(__subs_.begin(), __subs_.end(), -1) != __subs_.end() && __prev->suffix().length() != 0) {
+ __suffix_.matched = true;
+ __suffix_.first = __prev->suffix().first;
+ __suffix_.second = __prev->suffix().second;
+ __result_ = &__suffix_;
+ } else
+ __result_ = nullptr;
+ }
+ }
+ return *this;
+}
+
+// regex_replace
+
+template <class _OutputIterator, class _BidirectionalIterator, class _Traits, class _CharT>
+_LIBCPP_HIDE_FROM_ABI _OutputIterator regex_replace(
+ _OutputIterator __output_iter,
+ _BidirectionalIterator __first,
+ _BidirectionalIterator __last,
+ const basic_regex<_CharT, _Traits>& __e,
+ const _CharT* __fmt,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ typedef regex_iterator<_BidirectionalIterator, _CharT, _Traits> _Iter;
+ _Iter __i(__first, __last, __e, __flags);
+ _Iter __eof;
+ if (__i == __eof) {
+ if (!(__flags & regex_constants::format_no_copy))
+ __output_iter = std::copy(__first, __last, __output_iter);
+ } else {
+ sub_match<_BidirectionalIterator> __lm;
+ for (size_t __len = char_traits<_CharT>::length(__fmt); __i != __eof; ++__i) {
+ if (!(__flags & regex_constants::format_no_copy))
+ __output_iter = std::copy(__i->prefix().first, __i->prefix().second, __output_iter);
+ __output_iter = __i->format(__output_iter, __fmt, __fmt + __len, __flags);
+ __lm = __i->suffix();
+ if (__flags & regex_constants::format_first_only)
+ break;
+ }
+ if (!(__flags & regex_constants::format_no_copy))
+ __output_iter = std::copy(__lm.first, __lm.second, __output_iter);
+ }
+ return __output_iter;
+}
+
+template <class _OutputIterator, class _BidirectionalIterator, class _Traits, class _CharT, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI _OutputIterator regex_replace(
+ _OutputIterator __output_iter,
+ _BidirectionalIterator __first,
+ _BidirectionalIterator __last,
+ const basic_regex<_CharT, _Traits>& __e,
+ const basic_string<_CharT, _ST, _SA>& __fmt,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ return std::regex_replace(__output_iter, __first, __last, __e, __fmt.c_str(), __flags);
+}
+
+template <class _Traits, class _CharT, class _ST, class _SA, class _FST, class _FSA>
+inline _LIBCPP_HIDE_FROM_ABI basic_string<_CharT, _ST, _SA>
+regex_replace(const basic_string<_CharT, _ST, _SA>& __s,
+ const basic_regex<_CharT, _Traits>& __e,
+ const basic_string<_CharT, _FST, _FSA>& __fmt,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ basic_string<_CharT, _ST, _SA> __r;
+ std::regex_replace(std::back_inserter(__r), __s.begin(), __s.end(), __e, __fmt.c_str(), __flags);
+ return __r;
+}
+
+template <class _Traits, class _CharT, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI basic_string<_CharT, _ST, _SA>
+regex_replace(const basic_string<_CharT, _ST, _SA>& __s,
+ const basic_regex<_CharT, _Traits>& __e,
+ const _CharT* __fmt,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ basic_string<_CharT, _ST, _SA> __r;
+ std::regex_replace(std::back_inserter(__r), __s.begin(), __s.end(), __e, __fmt, __flags);
+ return __r;
+}
+
+template <class _Traits, class _CharT, class _ST, class _SA>
+inline _LIBCPP_HIDE_FROM_ABI basic_string<_CharT>
+regex_replace(const _CharT* __s,
+ const basic_regex<_CharT, _Traits>& __e,
+ const basic_string<_CharT, _ST, _SA>& __fmt,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ basic_string<_CharT> __r;
+ std::regex_replace(std::back_inserter(__r), __s, __s + char_traits<_CharT>::length(__s), __e, __fmt.c_str(), __flags);
+ return __r;
+}
+
+template <class _Traits, class _CharT>
+inline _LIBCPP_HIDE_FROM_ABI basic_string<_CharT>
+regex_replace(const _CharT* __s,
+ const basic_regex<_CharT, _Traits>& __e,
+ const _CharT* __fmt,
+ regex_constants::match_flag_type __flags = regex_constants::match_default) {
+ basic_string<_CharT> __r;
+ std::regex_replace(std::back_inserter(__r), __s, __s + char_traits<_CharT>::length(__s), __e, __fmt, __flags);
+ return __r;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _BidirT>
+using match_results _LIBCPP_AVAILABILITY_PMR =
+ std::match_results<_BidirT, polymorphic_allocator<std::sub_match<_BidirT>>>;
+
+using cmatch _LIBCPP_AVAILABILITY_PMR = match_results<const char*>;
+using smatch _LIBCPP_AVAILABILITY_PMR = match_results<std::pmr::string::const_iterator>;
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using wcmatch _LIBCPP_AVAILABILITY_PMR = match_results<const wchar_t*>;
+using wsmatch _LIBCPP_AVAILABILITY_PMR = match_results<std::pmr::wstring::const_iterator>;
+# endif
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <concepts>
+# include <cstdlib>
+# include <iosfwd>
+# include <iterator>
+# include <mutex>
+# include <new>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_REGEX
diff --git a/libcxx/include/__cxx03/scoped_allocator b/libcxx/include/__cxx03/scoped_allocator
new file mode 100644
index 00000000000000..a49ff465b1d55f
--- /dev/null
+++ b/libcxx/include/__cxx03/scoped_allocator
@@ -0,0 +1,573 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SCOPED_ALLOCATOR
+#define _LIBCPP_SCOPED_ALLOCATOR
+
+/*
+ scoped_allocator synopsis
+
+namespace std
+{
+
+template <class OuterAlloc, class... InnerAllocs>
+class scoped_allocator_adaptor : public OuterAlloc
+{
+ typedef allocator_traits<OuterAlloc> OuterTraits; // exposition only
+ scoped_allocator_adaptor<InnerAllocs...> inner; // exposition only
+public:
+
+ typedef OuterAlloc outer_allocator_type;
+ typedef see below inner_allocator_type;
+
+ typedef typename OuterTraits::value_type value_type;
+ typedef typename OuterTraits::size_type size_type;
+ typedef typename OuterTraits::difference_type difference_type;
+ typedef typename OuterTraits::pointer pointer;
+ typedef typename OuterTraits::const_pointer const_pointer;
+ typedef typename OuterTraits::void_pointer void_pointer;
+ typedef typename OuterTraits::const_void_pointer const_void_pointer;
+
+ typedef see below propagate_on_container_copy_assignment;
+ typedef see below propagate_on_container_move_assignment;
+ typedef see below propagate_on_container_swap;
+ typedef see below is_always_equal;
+
+ template <class Tp>
+ struct rebind
+ {
+ typedef scoped_allocator_adaptor<
+ OuterTraits::template rebind_alloc<Tp>, InnerAllocs...> other;
+ };
+
+ scoped_allocator_adaptor();
+ template <class OuterA2>
+ scoped_allocator_adaptor(OuterA2&& outerAlloc,
+ const InnerAllocs&... innerAllocs) noexcept;
+ scoped_allocator_adaptor(const scoped_allocator_adaptor& other) noexcept;
+ scoped_allocator_adaptor(scoped_allocator_adaptor&& other) noexcept;
+ template <class OuterA2>
+ scoped_allocator_adaptor(const scoped_allocator_adaptor<OuterA2, InnerAllocs...>& other) noexcept;
+ template <class OuterA2>
+ scoped_allocator_adaptor(const scoped_allocator_adaptor<OuterA2, InnerAllocs...>&& other) noexcept;
+
+ scoped_allocator_adaptor& operator=(const scoped_allocator_adaptor&) = default;
+ scoped_allocator_adaptor& operator=(scoped_allocator_adaptor&&) = default;
+ ~scoped_allocator_adaptor();
+
+ inner_allocator_type& inner_allocator() noexcept;
+ const inner_allocator_type& inner_allocator() const noexcept;
+
+ outer_allocator_type& outer_allocator() noexcept;
+ const outer_allocator_type& outer_allocator() const noexcept;
+
+ pointer allocate(size_type n); // [[nodiscard]] in C++20
+ pointer allocate(size_type n, const_void_pointer hint); // [[nodiscard]] in C++20
+ void deallocate(pointer p, size_type n) noexcept;
+
+ size_type max_size() const;
+ template <class T, class... Args> void construct(T* p, Args&& args);
+ template <class T1, class T2, class... Args1, class... Args2>
+ void construct(pair<T1, T2>* p, piecewise_construct t, tuple<Args1...> x,
+ tuple<Args2...> y);
+ template <class T1, class T2>
+ void construct(pair<T1, T2>* p);
+ template <class T1, class T2, class U, class V>
+ void construct(pair<T1, T2>* p, U&& x, V&& y);
+ template <class T1, class T2, class U, class V>
+ void construct(pair<T1, T2>* p, const pair<U, V>& x);
+ template <class T1, class T2, class U, class V>
+ void construct(pair<T1, T2>* p, pair<U, V>&& x);
+ template <class T> void destroy(T* p);
+
+ template <class T> void destroy(T* p) noexcept;
+
+ scoped_allocator_adaptor select_on_container_copy_construction() const noexcept;
+};
+
+template<class OuterAlloc, class... InnerAllocs>
+ scoped_allocator_adaptor(OuterAlloc, InnerAllocs...)
+ -> scoped_allocator_adaptor<OuterAlloc, InnerAllocs...>;
+
+template <class OuterA1, class OuterA2, class... InnerAllocs>
+ bool
+ operator==(const scoped_allocator_adaptor<OuterA1, InnerAllocs...>& a,
+ const scoped_allocator_adaptor<OuterA2, InnerAllocs...>& b) noexcept;
+
+template <class OuterA1, class OuterA2, class... InnerAllocs>
+ bool
+ operator!=(const scoped_allocator_adaptor<OuterA1, InnerAllocs...>& a,
+ const scoped_allocator_adaptor<OuterA2, InnerAllocs...>& b) noexcept; // removed in C++20
+
+} // std
+
+*/
+
+#include <__config>
+#include <__memory/allocator_traits.h>
+#include <__memory/uses_allocator_construction.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/piecewise_construct.h>
+#include <tuple>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if !defined(_LIBCPP_CXX03_LANG)
+
+// scoped_allocator_adaptor
+
+template <class... _Allocs>
+class scoped_allocator_adaptor;
+
+template <class... _Allocs>
+struct __get_poc_copy_assignment;
+
+template <class _A0>
+struct __get_poc_copy_assignment<_A0> {
+ static const bool value = allocator_traits<_A0>::propagate_on_container_copy_assignment::value;
+};
+
+template <class _A0, class... _Allocs>
+struct __get_poc_copy_assignment<_A0, _Allocs...> {
+ static const bool value = allocator_traits<_A0>::propagate_on_container_copy_assignment::value ||
+ __get_poc_copy_assignment<_Allocs...>::value;
+};
+
+template <class... _Allocs>
+struct __get_poc_move_assignment;
+
+template <class _A0>
+struct __get_poc_move_assignment<_A0> {
+ static const bool value = allocator_traits<_A0>::propagate_on_container_move_assignment::value;
+};
+
+template <class _A0, class... _Allocs>
+struct __get_poc_move_assignment<_A0, _Allocs...> {
+ static const bool value = allocator_traits<_A0>::propagate_on_container_move_assignment::value ||
+ __get_poc_move_assignment<_Allocs...>::value;
+};
+
+template <class... _Allocs>
+struct __get_poc_swap;
+
+template <class _A0>
+struct __get_poc_swap<_A0> {
+ static const bool value = allocator_traits<_A0>::propagate_on_container_swap::value;
+};
+
+template <class _A0, class... _Allocs>
+struct __get_poc_swap<_A0, _Allocs...> {
+ static const bool value =
+ allocator_traits<_A0>::propagate_on_container_swap::value || __get_poc_swap<_Allocs...>::value;
+};
+
+template <class... _Allocs>
+struct __get_is_always_equal;
+
+template <class _A0>
+struct __get_is_always_equal<_A0> {
+ static const bool value = allocator_traits<_A0>::is_always_equal::value;
+};
+
+template <class _A0, class... _Allocs>
+struct __get_is_always_equal<_A0, _Allocs...> {
+ static const bool value = allocator_traits<_A0>::is_always_equal::value && __get_is_always_equal<_Allocs...>::value;
+};
+
+template <class... _Allocs>
+class __scoped_allocator_storage;
+
+template <class _OuterAlloc, class... _InnerAllocs>
+class __scoped_allocator_storage<_OuterAlloc, _InnerAllocs...> : public _OuterAlloc {
+ typedef _OuterAlloc outer_allocator_type;
+
+protected:
+ typedef scoped_allocator_adaptor<_InnerAllocs...> inner_allocator_type;
+
+private:
+ inner_allocator_type __inner_;
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI __scoped_allocator_storage() _NOEXCEPT {}
+
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, _OuterA2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ __scoped_allocator_storage(_OuterA2&& __outer_alloc, const _InnerAllocs&... __inner_allocs) _NOEXCEPT
+ : outer_allocator_type(std::forward<_OuterA2>(__outer_alloc)),
+ __inner_(__inner_allocs...) {}
+
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, const _OuterA2&>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ __scoped_allocator_storage(const __scoped_allocator_storage<_OuterA2, _InnerAllocs...>& __other) _NOEXCEPT
+ : outer_allocator_type(__other.outer_allocator()),
+ __inner_(__other.inner_allocator()) {}
+
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, _OuterA2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ __scoped_allocator_storage(__scoped_allocator_storage<_OuterA2, _InnerAllocs...>&& __other) _NOEXCEPT
+ : outer_allocator_type(std::move(__other.outer_allocator())),
+ __inner_(std::move(__other.inner_allocator())) {}
+
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, _OuterA2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI __scoped_allocator_storage(_OuterA2&& __o, const inner_allocator_type& __i) _NOEXCEPT
+ : outer_allocator_type(std::forward<_OuterA2>(__o)),
+ __inner_(__i) {}
+
+ _LIBCPP_HIDE_FROM_ABI inner_allocator_type& inner_allocator() _NOEXCEPT { return __inner_; }
+ _LIBCPP_HIDE_FROM_ABI const inner_allocator_type& inner_allocator() const _NOEXCEPT { return __inner_; }
+
+ _LIBCPP_HIDE_FROM_ABI outer_allocator_type& outer_allocator() _NOEXCEPT {
+ return static_cast<outer_allocator_type&>(*this);
+ }
+ _LIBCPP_HIDE_FROM_ABI const outer_allocator_type& outer_allocator() const _NOEXCEPT {
+ return static_cast<const outer_allocator_type&>(*this);
+ }
+
+ scoped_allocator_adaptor<outer_allocator_type, _InnerAllocs...> _LIBCPP_HIDE_FROM_ABI
+ select_on_container_copy_construction() const _NOEXCEPT {
+ return scoped_allocator_adaptor<outer_allocator_type, _InnerAllocs...>(
+ allocator_traits<outer_allocator_type>::select_on_container_copy_construction(outer_allocator()),
+ allocator_traits<inner_allocator_type>::select_on_container_copy_construction(inner_allocator()));
+ }
+
+ template <class...>
+ friend class __scoped_allocator_storage;
+};
+
+template <class _OuterAlloc>
+class __scoped_allocator_storage<_OuterAlloc> : public _OuterAlloc {
+ typedef _OuterAlloc outer_allocator_type;
+
+protected:
+ typedef scoped_allocator_adaptor<_OuterAlloc> inner_allocator_type;
+
+ _LIBCPP_HIDE_FROM_ABI __scoped_allocator_storage() _NOEXCEPT {}
+
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, _OuterA2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI __scoped_allocator_storage(_OuterA2&& __outer_alloc) _NOEXCEPT
+ : outer_allocator_type(std::forward<_OuterA2>(__outer_alloc)) {}
+
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, const _OuterA2&>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI __scoped_allocator_storage(const __scoped_allocator_storage<_OuterA2>& __other) _NOEXCEPT
+ : outer_allocator_type(__other.outer_allocator()) {}
+
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, _OuterA2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI __scoped_allocator_storage(__scoped_allocator_storage<_OuterA2>&& __other) _NOEXCEPT
+ : outer_allocator_type(std::move(__other.outer_allocator())) {}
+
+ _LIBCPP_HIDE_FROM_ABI inner_allocator_type& inner_allocator() _NOEXCEPT {
+ return static_cast<inner_allocator_type&>(*this);
+ }
+ _LIBCPP_HIDE_FROM_ABI const inner_allocator_type& inner_allocator() const _NOEXCEPT {
+ return static_cast<const inner_allocator_type&>(*this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI outer_allocator_type& outer_allocator() _NOEXCEPT {
+ return static_cast<outer_allocator_type&>(*this);
+ }
+ _LIBCPP_HIDE_FROM_ABI const outer_allocator_type& outer_allocator() const _NOEXCEPT {
+ return static_cast<const outer_allocator_type&>(*this);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI scoped_allocator_adaptor<outer_allocator_type>
+ select_on_container_copy_construction() const _NOEXCEPT {
+ return scoped_allocator_adaptor<outer_allocator_type>(
+ allocator_traits<outer_allocator_type>::select_on_container_copy_construction(outer_allocator()));
+ }
+
+ __scoped_allocator_storage(const outer_allocator_type& __o, const inner_allocator_type& __i) _NOEXCEPT;
+
+ template <class...>
+ friend class __scoped_allocator_storage;
+};
+
+// __outermost
+
+template <class _Alloc>
+decltype(std::declval<_Alloc>().outer_allocator(), true_type()) __has_outer_allocator_test(_Alloc&& __a);
+
+template <class _Alloc>
+false_type __has_outer_allocator_test(const volatile _Alloc& __a);
+
+template <class _Alloc>
+struct __has_outer_allocator
+ : public common_type< decltype(std::__has_outer_allocator_test(std::declval<_Alloc&>()))>::type {};
+
+template <class _Alloc, bool = __has_outer_allocator<_Alloc>::value>
+struct __outermost {
+ typedef _Alloc type;
+ _LIBCPP_HIDE_FROM_ABI type& operator()(type& __a) const _NOEXCEPT { return __a; }
+};
+
+template <class _Alloc>
+struct __outermost<_Alloc, true> {
+ typedef __libcpp_remove_reference_t< decltype(std::declval<_Alloc>().outer_allocator()) > _OuterAlloc;
+ typedef typename __outermost<_OuterAlloc>::type type;
+ _LIBCPP_HIDE_FROM_ABI type& operator()(_Alloc& __a) const _NOEXCEPT {
+ return __outermost<_OuterAlloc>()(__a.outer_allocator());
+ }
+};
+
+template <class _OuterAlloc, class... _InnerAllocs>
+class _LIBCPP_TEMPLATE_VIS scoped_allocator_adaptor<_OuterAlloc, _InnerAllocs...>
+ : public __scoped_allocator_storage<_OuterAlloc, _InnerAllocs...> {
+ typedef __scoped_allocator_storage<_OuterAlloc, _InnerAllocs...> _Base;
+ typedef allocator_traits<_OuterAlloc> _OuterTraits;
+
+public:
+ typedef _OuterAlloc outer_allocator_type;
+ typedef typename _Base::inner_allocator_type inner_allocator_type;
+ typedef typename _OuterTraits::size_type size_type;
+ typedef typename _OuterTraits::difference_type difference_type;
+ typedef typename _OuterTraits::pointer pointer;
+ typedef typename _OuterTraits::const_pointer const_pointer;
+ typedef typename _OuterTraits::void_pointer void_pointer;
+ typedef typename _OuterTraits::const_void_pointer const_void_pointer;
+
+ typedef integral_constant< bool, __get_poc_copy_assignment<outer_allocator_type, _InnerAllocs...>::value >
+ propagate_on_container_copy_assignment;
+ typedef integral_constant< bool, __get_poc_move_assignment<outer_allocator_type, _InnerAllocs...>::value >
+ propagate_on_container_move_assignment;
+ typedef integral_constant< bool, __get_poc_swap<outer_allocator_type, _InnerAllocs...>::value >
+ propagate_on_container_swap;
+ typedef integral_constant< bool, __get_is_always_equal<outer_allocator_type, _InnerAllocs...>::value >
+ is_always_equal;
+
+ template <class _Tp>
+ struct rebind {
+ typedef scoped_allocator_adaptor< typename _OuterTraits::template rebind_alloc<_Tp>, _InnerAllocs... > other;
+ };
+
+ _LIBCPP_HIDE_FROM_ABI scoped_allocator_adaptor() _NOEXCEPT {}
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, _OuterA2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ scoped_allocator_adaptor(_OuterA2&& __outer_alloc, const _InnerAllocs&... __inner_allocs) _NOEXCEPT
+ : _Base(std::forward<_OuterA2>(__outer_alloc), __inner_allocs...) {}
+ // scoped_allocator_adaptor(const scoped_allocator_adaptor& __other) = default;
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, const _OuterA2&>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ scoped_allocator_adaptor(const scoped_allocator_adaptor<_OuterA2, _InnerAllocs...>& __other) _NOEXCEPT
+ : _Base(__other) {}
+ template <class _OuterA2, __enable_if_t<is_constructible<outer_allocator_type, _OuterA2>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ scoped_allocator_adaptor(scoped_allocator_adaptor<_OuterA2, _InnerAllocs...>&& __other) _NOEXCEPT
+ : _Base(std::move(__other)) {}
+
+ // scoped_allocator_adaptor& operator=(const scoped_allocator_adaptor&) = default;
+ // scoped_allocator_adaptor& operator=(scoped_allocator_adaptor&&) = default;
+ // ~scoped_allocator_adaptor() = default;
+
+ _LIBCPP_HIDE_FROM_ABI inner_allocator_type& inner_allocator() _NOEXCEPT { return _Base::inner_allocator(); }
+ _LIBCPP_HIDE_FROM_ABI const inner_allocator_type& inner_allocator() const _NOEXCEPT {
+ return _Base::inner_allocator();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI outer_allocator_type& outer_allocator() _NOEXCEPT { return _Base::outer_allocator(); }
+ _LIBCPP_HIDE_FROM_ABI const outer_allocator_type& outer_allocator() const _NOEXCEPT {
+ return _Base::outer_allocator();
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI pointer allocate(size_type __n) {
+ return allocator_traits<outer_allocator_type>::allocate(outer_allocator(), __n);
+ }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI pointer allocate(size_type __n, const_void_pointer __hint) {
+ return allocator_traits<outer_allocator_type>::allocate(outer_allocator(), __n, __hint);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void deallocate(pointer __p, size_type __n) _NOEXCEPT {
+ allocator_traits<outer_allocator_type>::deallocate(outer_allocator(), __p, __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const {
+ return allocator_traits<outer_allocator_type>::max_size(outer_allocator());
+ }
+
+# if _LIBCPP_STD_VER >= 20
+ template <class _Type, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void construct(_Type* __ptr, _Args&&... __args) {
+ using _OM = __outermost<outer_allocator_type>;
+ std::apply(
+ [__ptr, this](auto&&... __newargs) {
+ allocator_traits<typename _OM::type>::construct(
+ _OM()(outer_allocator()), __ptr, std::forward<decltype(__newargs)>(__newargs)...);
+ },
+ std::uses_allocator_construction_args<_Type>(inner_allocator(), std::forward<_Args>(__args)...));
+ }
+# else
+ template <class _Tp, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void construct(_Tp* __p, _Args&&... __args) {
+ __construct(__uses_alloc_ctor<_Tp, inner_allocator_type&, _Args...>(), __p, std::forward<_Args>(__args)...);
+ }
+
+ template <class _T1, class _T2, class... _Args1, class... _Args2>
+ _LIBCPP_HIDE_FROM_ABI void
+ construct(pair<_T1, _T2>* __p, piecewise_construct_t, tuple<_Args1...> __x, tuple<_Args2...> __y) {
+ typedef __outermost<outer_allocator_type> _OM;
+ allocator_traits<typename _OM::type>::construct(
+ _OM()(outer_allocator()),
+ __p,
+ piecewise_construct,
+ __transform_tuple(typename __uses_alloc_ctor< _T1, inner_allocator_type&, _Args1... >::type(),
+ std::move(__x),
+ typename __make_tuple_indices<sizeof...(_Args1)>::type{}),
+ __transform_tuple(typename __uses_alloc_ctor< _T2, inner_allocator_type&, _Args2... >::type(),
+ std::move(__y),
+ typename __make_tuple_indices<sizeof...(_Args2)>::type{}));
+ }
+
+ template <class _T1, class _T2>
+ _LIBCPP_HIDE_FROM_ABI void construct(pair<_T1, _T2>* __p) {
+ construct(__p, piecewise_construct, tuple<>{}, tuple<>{});
+ }
+
+ template <class _T1, class _T2, class _Up, class _Vp>
+ _LIBCPP_HIDE_FROM_ABI void construct(pair<_T1, _T2>* __p, _Up&& __x, _Vp&& __y) {
+ construct(__p,
+ piecewise_construct,
+ std::forward_as_tuple(std::forward<_Up>(__x)),
+ std::forward_as_tuple(std::forward<_Vp>(__y)));
+ }
+
+ template <class _T1, class _T2, class _Up, class _Vp>
+ _LIBCPP_HIDE_FROM_ABI void construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x) {
+ construct(__p, piecewise_construct, std::forward_as_tuple(__x.first), std::forward_as_tuple(__x.second));
+ }
+
+ template <class _T1, class _T2, class _Up, class _Vp>
+ _LIBCPP_HIDE_FROM_ABI void construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x) {
+ construct(__p,
+ piecewise_construct,
+ std::forward_as_tuple(std::forward<_Up>(__x.first)),
+ std::forward_as_tuple(std::forward<_Vp>(__x.second)));
+ }
+# endif
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI void destroy(_Tp* __p) {
+ typedef __outermost<outer_allocator_type> _OM;
+ allocator_traits<typename _OM::type>::destroy(_OM()(outer_allocator()), __p);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI scoped_allocator_adaptor select_on_container_copy_construction() const _NOEXCEPT {
+ return _Base::select_on_container_copy_construction();
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI explicit scoped_allocator_adaptor(
+ outer_allocator_type&& __o, inner_allocator_type&& __i) _NOEXCEPT : _Base(std::move(__o), std::move(__i)) {}
+
+ template <class _Tp, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void __construct(integral_constant<int, 0>, _Tp* __p, _Args&&... __args) {
+ typedef __outermost<outer_allocator_type> _OM;
+ allocator_traits<typename _OM::type>::construct(_OM()(outer_allocator()), __p, std::forward<_Args>(__args)...);
+ }
+
+ template <class _Tp, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void __construct(integral_constant<int, 1>, _Tp* __p, _Args&&... __args) {
+ typedef __outermost<outer_allocator_type> _OM;
+ allocator_traits<typename _OM::type>::construct(
+ _OM()(outer_allocator()), __p, allocator_arg, inner_allocator(), std::forward<_Args>(__args)...);
+ }
+
+ template <class _Tp, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI void __construct(integral_constant<int, 2>, _Tp* __p, _Args&&... __args) {
+ typedef __outermost<outer_allocator_type> _OM;
+ allocator_traits<typename _OM::type>::construct(
+ _OM()(outer_allocator()), __p, std::forward<_Args>(__args)..., inner_allocator());
+ }
+
+ template <class... _Args, size_t... _Idx>
+ _LIBCPP_HIDE_FROM_ABI tuple<_Args&&...>
+ __transform_tuple(integral_constant<int, 0>, tuple<_Args...>&& __t, __tuple_indices<_Idx...>) {
+ return std::forward_as_tuple(std::get<_Idx>(std::move(__t))...);
+ }
+
+ template <class... _Args, size_t... _Idx>
+ _LIBCPP_HIDE_FROM_ABI tuple<allocator_arg_t, inner_allocator_type&, _Args&&...>
+ __transform_tuple(integral_constant<int, 1>, tuple<_Args...>&& __t, __tuple_indices<_Idx...>) {
+ using _Tup = tuple<allocator_arg_t, inner_allocator_type&, _Args&&...>;
+ return _Tup(allocator_arg, inner_allocator(), std::get<_Idx>(std::move(__t))...);
+ }
+
+ template <class... _Args, size_t... _Idx>
+ _LIBCPP_HIDE_FROM_ABI tuple<_Args&&..., inner_allocator_type&>
+ __transform_tuple(integral_constant<int, 2>, tuple<_Args...>&& __t, __tuple_indices<_Idx...>) {
+ using _Tup = tuple<_Args&&..., inner_allocator_type&>;
+ return _Tup(std::get<_Idx>(std::move(__t))..., inner_allocator());
+ }
+
+ template <class...>
+ friend class __scoped_allocator_storage;
+};
+
+# if _LIBCPP_STD_VER >= 17
+template <class _OuterAlloc, class... _InnerAllocs>
+scoped_allocator_adaptor(_OuterAlloc, _InnerAllocs...) -> scoped_allocator_adaptor<_OuterAlloc, _InnerAllocs...>;
+# endif
+
+template <class _OuterA1, class _OuterA2>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const scoped_allocator_adaptor<_OuterA1>& __a, const scoped_allocator_adaptor<_OuterA2>& __b) _NOEXCEPT {
+ return __a.outer_allocator() == __b.outer_allocator();
+}
+
+template <class _OuterA1, class _OuterA2, class _InnerA0, class... _InnerAllocs>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const scoped_allocator_adaptor<_OuterA1, _InnerA0, _InnerAllocs...>& __a,
+ const scoped_allocator_adaptor<_OuterA2, _InnerA0, _InnerAllocs...>& __b) _NOEXCEPT {
+ return __a.outer_allocator() == __b.outer_allocator() && __a.inner_allocator() == __b.inner_allocator();
+}
+
+# if _LIBCPP_STD_VER <= 17
+
+template <class _OuterA1, class _OuterA2, class... _InnerAllocs>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const scoped_allocator_adaptor<_OuterA1, _InnerAllocs...>& __a,
+ const scoped_allocator_adaptor<_OuterA2, _InnerAllocs...>& __b) _NOEXCEPT {
+ return !(__a == __b);
+}
+
+# endif // _LIBCPP_STD_VER <= 17
+
+#endif // !defined(_LIBCPP_CXX03_LANG)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+# include <climits>
+# include <concepts>
+# include <cstring>
+# include <ctime>
+# include <iterator>
+# include <memory>
+# include <ratio>
+# include <stdexcept>
+# include <type_traits>
+# include <variant>
+#endif
+
+#endif // _LIBCPP_SCOPED_ALLOCATOR
diff --git a/libcxx/include/__cxx03/semaphore b/libcxx/include/__cxx03/semaphore
new file mode 100644
index 00000000000000..95a4375f21c175
--- /dev/null
+++ b/libcxx/include/__cxx03/semaphore
@@ -0,0 +1,188 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SEMAPHORE
+#define _LIBCPP_SEMAPHORE
+
+/*
+ semaphore synopsis
+
+namespace std {
+
+template<ptrdiff_t least_max_value = implementation-defined>
+class counting_semaphore
+{
+public:
+static constexpr ptrdiff_t max() noexcept;
+
+constexpr explicit counting_semaphore(ptrdiff_t desired);
+~counting_semaphore();
+
+counting_semaphore(const counting_semaphore&) = delete;
+counting_semaphore& operator=(const counting_semaphore&) = delete;
+
+void release(ptrdiff_t update = 1);
+void acquire();
+bool try_acquire() noexcept;
+template<class Rep, class Period>
+ bool try_acquire_for(const chrono::duration<Rep, Period>& rel_time);
+template<class Clock, class Duration>
+ bool try_acquire_until(const chrono::time_point<Clock, Duration>& abs_time);
+
+private:
+ptrdiff_t counter; // exposition only
+};
+
+using binary_semaphore = counting_semaphore<1>;
+
+}
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+# include <__assert>
+# include <__atomic/atomic_base.h>
+# include <__atomic/atomic_sync.h>
+# include <__atomic/memory_order.h>
+# include <__chrono/time_point.h>
+# include <__thread/poll_with_backoff.h>
+# include <__thread/support.h>
+# include <__thread/timed_backoff_policy.h>
+# include <cstddef>
+# include <limits>
+# include <version>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+# if _LIBCPP_STD_VER >= 14
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+/*
+
+__atomic_semaphore_base is the general-case implementation.
+It is a typical Dijkstra semaphore algorithm over atomics, wait and notify
+functions. It avoids contention against users' own use of those facilities.
+
+*/
+
+# define _LIBCPP_SEMAPHORE_MAX (numeric_limits<ptrdiff_t>::max())
+
+class __atomic_semaphore_base {
+ __atomic_base<ptrdiff_t> __a_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __atomic_semaphore_base(ptrdiff_t __count) : __a_(__count) {}
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void release(ptrdiff_t __update = 1) {
+ auto __old = __a_.fetch_add(__update, memory_order_release);
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __update <= _LIBCPP_SEMAPHORE_MAX - __old, "update is greater than the expected value");
+ if (__old == 0) {
+ __a_.notify_all();
+ }
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void acquire() {
+ std::__atomic_wait_unless(
+ __a_, [this](ptrdiff_t& __old) { return __try_acquire_impl(__old); }, memory_order_relaxed);
+ }
+ template <class _Rep, class _Period>
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool
+ try_acquire_for(chrono::duration<_Rep, _Period> const& __rel_time) {
+ if (__rel_time == chrono::duration<_Rep, _Period>::zero())
+ return try_acquire();
+ auto const __poll_fn = [this]() { return try_acquire(); };
+ return std::__libcpp_thread_poll_with_backoff(__poll_fn, __libcpp_timed_backoff_policy(), __rel_time);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool try_acquire() {
+ auto __old = __a_.load(memory_order_relaxed);
+ return __try_acquire_impl(__old);
+ }
+
+private:
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool __try_acquire_impl(ptrdiff_t& __old) {
+ while (true) {
+ if (__old == 0)
+ return false;
+ if (__a_.compare_exchange_weak(__old, __old - 1, memory_order_acquire, memory_order_relaxed))
+ return true;
+ }
+ }
+};
+
+template <ptrdiff_t __least_max_value = _LIBCPP_SEMAPHORE_MAX>
+class _LIBCPP_DEPRECATED_ATOMIC_SYNC counting_semaphore {
+ __atomic_semaphore_base __semaphore_;
+
+public:
+ static_assert(__least_max_value >= 0, "The least maximum value must be a positive number");
+
+ static constexpr ptrdiff_t max() noexcept { return __least_max_value; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit counting_semaphore(ptrdiff_t __count) : __semaphore_(__count) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __count >= 0,
+ "counting_semaphore::counting_semaphore(ptrdiff_t): counting_semaphore cannot be "
+ "initialized with a negative value");
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(
+ __count <= max(),
+ "counting_semaphore::counting_semaphore(ptrdiff_t): counting_semaphore cannot be "
+ "initialized with a value greater than max()");
+ }
+ ~counting_semaphore() = default;
+
+ counting_semaphore(const counting_semaphore&) = delete;
+ counting_semaphore& operator=(const counting_semaphore&) = delete;
+
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void release(ptrdiff_t __update = 1) {
+ _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(__update >= 0, "counting_semaphore:release called with a negative value");
+ __semaphore_.release(__update);
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI void acquire() { __semaphore_.acquire(); }
+ template <class _Rep, class _Period>
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool
+ try_acquire_for(chrono::duration<_Rep, _Period> const& __rel_time) {
+ return __semaphore_.try_acquire_for(chrono::duration_cast<chrono::nanoseconds>(__rel_time));
+ }
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool try_acquire() { return __semaphore_.try_acquire(); }
+ template <class _Clock, class _Duration>
+ _LIBCPP_AVAILABILITY_SYNC _LIBCPP_HIDE_FROM_ABI bool
+ try_acquire_until(chrono::time_point<_Clock, _Duration> const& __abs_time) {
+ auto const __current = _Clock::now();
+ if (__current >= __abs_time)
+ return try_acquire();
+ else
+ return try_acquire_for(__abs_time - __current);
+ }
+};
+
+_LIBCPP_SUPPRESS_DEPRECATED_PUSH
+using binary_semaphore _LIBCPP_DEPRECATED_ATOMIC_SYNC = counting_semaphore<1>;
+_LIBCPP_SUPPRESS_DEPRECATED_POP
+
+_LIBCPP_END_NAMESPACE_STD
+
+# endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_THREADS)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <atomic>
+#endif
+
+#endif //_LIBCPP_SEMAPHORE
diff --git a/libcxx/include/__cxx03/set b/libcxx/include/__cxx03/set
new file mode 100644
index 00000000000000..94533583798699
--- /dev/null
+++ b/libcxx/include/__cxx03/set
@@ -0,0 +1,1501 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SET
+#define _LIBCPP_SET
+
+/*
+
+ set synopsis
+
+namespace std
+{
+
+template <class Key, class Compare = less<Key>,
+ class Allocator = allocator<Key>>
+class set
+{
+public:
+ // types:
+ typedef Key key_type;
+ typedef key_type value_type;
+ typedef Compare key_compare;
+ typedef key_compare value_compare;
+ typedef Allocator allocator_type;
+ typedef typename allocator_type::reference reference;
+ typedef typename allocator_type::const_reference const_reference;
+ typedef typename allocator_type::size_type size_type;
+ typedef typename allocator_type::difference_type difference_type;
+ typedef typename allocator_type::pointer pointer;
+ typedef typename allocator_type::const_pointer const_pointer;
+
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+ typedef unspecified node_type; // C++17
+ typedef INSERT_RETURN_TYPE<iterator, node_type> insert_return_type; // C++17
+
+ // construct/copy/destroy:
+ set()
+ noexcept(
+ is_nothrow_default_constructible<allocator_type>::value &&
+ is_nothrow_default_constructible<key_compare>::value &&
+ is_nothrow_copy_constructible<key_compare>::value);
+ explicit set(const value_compare& comp);
+ set(const value_compare& comp, const allocator_type& a);
+ template <class InputIterator>
+ set(InputIterator first, InputIterator last,
+ const value_compare& comp = value_compare());
+ template <class InputIterator>
+ set(InputIterator first, InputIterator last, const value_compare& comp,
+ const allocator_type& a);
+ template<container-compatible-range<value_type> R>
+ set(from_range_t, R&& rg, const Compare& comp = Compare(), const Allocator& = Allocator()); // C++23
+ set(const set& s);
+ set(set&& s)
+ noexcept(
+ is_nothrow_move_constructible<allocator_type>::value &&
+ is_nothrow_move_constructible<key_compare>::value);
+ explicit set(const allocator_type& a);
+ set(const set& s, const allocator_type& a);
+ set(set&& s, const allocator_type& a);
+ set(initializer_list<value_type> il, const value_compare& comp = value_compare());
+ set(initializer_list<value_type> il, const value_compare& comp,
+ const allocator_type& a);
+ template <class InputIterator>
+ set(InputIterator first, InputIterator last, const allocator_type& a)
+ : set(first, last, Compare(), a) {} // C++14
+ template<container-compatible-range<value_type> R>
+ set(from_range_t, R&& rg, const Allocator& a))
+ : set(from_range, std::forward<R>(rg), Compare(), a) { } // C++23
+ set(initializer_list<value_type> il, const allocator_type& a)
+ : set(il, Compare(), a) {} // C++14
+ ~set();
+
+ set& operator=(const set& s);
+ set& operator=(set&& s)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value &&
+ is_nothrow_move_assignable<key_compare>::value);
+ set& operator=(initializer_list<value_type> il);
+
+ // iterators:
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+
+ reverse_iterator rbegin() noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ reverse_iterator rend() noexcept;
+ const_reverse_iterator rend() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ // capacity:
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ // modifiers:
+ template <class... Args>
+ pair<iterator, bool> emplace(Args&&... args);
+ template <class... Args>
+ iterator emplace_hint(const_iterator position, Args&&... args);
+ pair<iterator,bool> insert(const value_type& v);
+ pair<iterator,bool> insert(value_type&& v);
+ iterator insert(const_iterator position, const value_type& v);
+ iterator insert(const_iterator position, value_type&& v);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+ template<container-compatible-range<value_type> R>
+ void insert_range(R&& rg); // C++23
+ void insert(initializer_list<value_type> il);
+
+ node_type extract(const_iterator position); // C++17
+ node_type extract(const key_type& x); // C++17
+ insert_return_type insert(node_type&& nh); // C++17
+ iterator insert(const_iterator hint, node_type&& nh); // C++17
+
+ iterator erase(const_iterator position);
+ iterator erase(iterator position); // C++14
+ size_type erase(const key_type& k);
+ iterator erase(const_iterator first, const_iterator last);
+ void clear() noexcept;
+
+ template<class C2>
+ void merge(set<Key, C2, Allocator>& source); // C++17
+ template<class C2>
+ void merge(set<Key, C2, Allocator>&& source); // C++17
+ template<class C2>
+ void merge(multiset<Key, C2, Allocator>& source); // C++17
+ template<class C2>
+ void merge(multiset<Key, C2, Allocator>&& source); // C++17
+
+ void swap(set& s)
+ noexcept(
+ __is_nothrow_swappable<key_compare>::value &&
+ (!allocator_type::propagate_on_container_swap::value ||
+ __is_nothrow_swappable<allocator_type>::value));
+
+ // observers:
+ allocator_type get_allocator() const noexcept;
+ key_compare key_comp() const;
+ value_compare value_comp() const;
+
+ // set operations:
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ template<typename K>
+ iterator find(const K& x);
+ template<typename K>
+ const_iterator find(const K& x) const; // C++14
+
+ template<typename K>
+ size_type count(const K& x) const; // C++14
+ size_type count(const key_type& k) const;
+
+ bool contains(const key_type& x) const; // C++20
+ template<class K> bool contains(const K& x) const; // C++20
+
+ iterator lower_bound(const key_type& k);
+ const_iterator lower_bound(const key_type& k) const;
+ template<typename K>
+ iterator lower_bound(const K& x); // C++14
+ template<typename K>
+ const_iterator lower_bound(const K& x) const; // C++14
+
+ iterator upper_bound(const key_type& k);
+ const_iterator upper_bound(const key_type& k) const;
+ template<typename K>
+ iterator upper_bound(const K& x); // C++14
+ template<typename K>
+ const_iterator upper_bound(const K& x) const; // C++14
+ pair<iterator,iterator> equal_range(const key_type& k);
+ pair<const_iterator,const_iterator> equal_range(const key_type& k) const;
+ template<typename K>
+ pair<iterator,iterator> equal_range(const K& x); // C++14
+ template<typename K>
+ pair<const_iterator,const_iterator> equal_range(const K& x) const; // C++14
+};
+
+template <class InputIterator,
+ class Compare = less<typename iterator_traits<InputIterator>::value_type>,
+ class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+set(InputIterator, InputIterator,
+ Compare = Compare(), Allocator = Allocator())
+ -> set<typename iterator_traits<InputIterator>::value_type, Compare, Allocator>; // C++17
+
+template<ranges::input_range R, class Compare = less<ranges::range_value_t<R>>,
+ class Allocator = allocator<ranges::range_value_t<R>>>
+ set(from_range_t, R&&, Compare = Compare(), Allocator = Allocator())
+ -> set<ranges::range_value_t<R>, Compare, Allocator>; // C++23
+
+template<class Key, class Compare = less<Key>, class Allocator = allocator<Key>>
+set(initializer_list<Key>, Compare = Compare(), Allocator = Allocator())
+ -> set<Key, Compare, Allocator>; // C++17
+
+template<class InputIterator, class Allocator>
+set(InputIterator, InputIterator, Allocator)
+ -> set<typename iterator_traits<InputIterator>::value_type,
+ less<typename iterator_traits<InputIterator>::value_type>, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator>
+ set(from_range_t, R&&, Allocator)
+ -> set<ranges::range_value_t<R>, less<ranges::range_value_t<R>>, Allocator>; // C++23
+
+template<class Key, class Allocator>
+set(initializer_list<Key>, Allocator) -> set<Key, less<Key>, Allocator>; // C++17
+
+template <class Key, class Compare, class Allocator>
+bool
+operator==(const set<Key, Compare, Allocator>& x,
+ const set<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator< (const set<Key, Compare, Allocator>& x,
+ const set<Key, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class Compare, class Allocator>
+bool
+operator!=(const set<Key, Compare, Allocator>& x,
+ const set<Key, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class Compare, class Allocator>
+bool
+operator> (const set<Key, Compare, Allocator>& x,
+ const set<Key, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class Compare, class Allocator>
+bool
+operator>=(const set<Key, Compare, Allocator>& x,
+ const set<Key, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class Compare, class Allocator>
+bool
+operator<=(const set<Key, Compare, Allocator>& x,
+ const set<Key, Compare, Allocator>& y); // removed in C++20
+
+template<class Key, class Compare, class Allocator>
+ synth-three-way-result<Key> operator<=>(const set<Key, Compare, Allocator>& x,
+ const set<Key, Compare, Allocator>& y); // since C++20
+
+// specialized algorithms:
+template <class Key, class Compare, class Allocator>
+void
+swap(set<Key, Compare, Allocator>& x, set<Key, Compare, Allocator>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class Key, class Compare, class Allocator, class Predicate>
+typename set<Key, Compare, Allocator>::size_type
+erase_if(set<Key, Compare, Allocator>& c, Predicate pred); // C++20
+
+template <class Key, class Compare = less<Key>,
+ class Allocator = allocator<Key>>
+class multiset
+{
+public:
+ // types:
+ typedef Key key_type;
+ typedef key_type value_type;
+ typedef Compare key_compare;
+ typedef key_compare value_compare;
+ typedef Allocator allocator_type;
+ typedef typename allocator_type::reference reference;
+ typedef typename allocator_type::const_reference const_reference;
+ typedef typename allocator_type::size_type size_type;
+ typedef typename allocator_type::difference_type difference_type;
+ typedef typename allocator_type::pointer pointer;
+ typedef typename allocator_type::const_pointer const_pointer;
+
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+ typedef unspecified node_type; // C++17
+
+ // construct/copy/destroy:
+ multiset()
+ noexcept(
+ is_nothrow_default_constructible<allocator_type>::value &&
+ is_nothrow_default_constructible<key_compare>::value &&
+ is_nothrow_copy_constructible<key_compare>::value);
+ explicit multiset(const value_compare& comp);
+ multiset(const value_compare& comp, const allocator_type& a);
+ template <class InputIterator>
+ multiset(InputIterator first, InputIterator last,
+ const value_compare& comp = value_compare());
+ template <class InputIterator>
+ multiset(InputIterator first, InputIterator last,
+ const value_compare& comp, const allocator_type& a);
+ template<container-compatible-range<value_type> R>
+ multiset(from_range_t, R&& rg,
+ const Compare& comp = Compare(), const Allocator& = Allocator()); // C++23
+ multiset(const multiset& s);
+ multiset(multiset&& s)
+ noexcept(
+ is_nothrow_move_constructible<allocator_type>::value &&
+ is_nothrow_move_constructible<key_compare>::value);
+ explicit multiset(const allocator_type& a);
+ multiset(const multiset& s, const allocator_type& a);
+ multiset(multiset&& s, const allocator_type& a);
+ multiset(initializer_list<value_type> il, const value_compare& comp = value_compare());
+ multiset(initializer_list<value_type> il, const value_compare& comp,
+ const allocator_type& a);
+ template <class InputIterator>
+ multiset(InputIterator first, InputIterator last, const allocator_type& a)
+ : set(first, last, Compare(), a) {} // C++14
+ template<container-compatible-range<value_type> R>
+ multiset(from_range_t, R&& rg, const Allocator& a))
+ : multiset(from_range, std::forward<R>(rg), Compare(), a) { } // C++23
+ multiset(initializer_list<value_type> il, const allocator_type& a)
+ : set(il, Compare(), a) {} // C++14
+ ~multiset();
+
+ multiset& operator=(const multiset& s);
+ multiset& operator=(multiset&& s)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value &&
+ is_nothrow_move_assignable<key_compare>::value);
+ multiset& operator=(initializer_list<value_type> il);
+
+ // iterators:
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+
+ reverse_iterator rbegin() noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ reverse_iterator rend() noexcept;
+ const_reverse_iterator rend() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ // capacity:
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ // modifiers:
+ template <class... Args>
+ iterator emplace(Args&&... args);
+ template <class... Args>
+ iterator emplace_hint(const_iterator position, Args&&... args);
+ iterator insert(const value_type& v);
+ iterator insert(value_type&& v);
+ iterator insert(const_iterator position, const value_type& v);
+ iterator insert(const_iterator position, value_type&& v);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+ template<container-compatible-range<value_type> R>
+ void insert_range(R&& rg); // C++23
+ void insert(initializer_list<value_type> il);
+
+ node_type extract(const_iterator position); // C++17
+ node_type extract(const key_type& x); // C++17
+ iterator insert(node_type&& nh); // C++17
+ iterator insert(const_iterator hint, node_type&& nh); // C++17
+
+ iterator erase(const_iterator position);
+ iterator erase(iterator position); // C++14
+ size_type erase(const key_type& k);
+ iterator erase(const_iterator first, const_iterator last);
+ void clear() noexcept;
+
+ template<class C2>
+ void merge(multiset<Key, C2, Allocator>& source); // C++17
+ template<class C2>
+ void merge(multiset<Key, C2, Allocator>&& source); // C++17
+ template<class C2>
+ void merge(set<Key, C2, Allocator>& source); // C++17
+ template<class C2>
+ void merge(set<Key, C2, Allocator>&& source); // C++17
+
+ void swap(multiset& s)
+ noexcept(
+ __is_nothrow_swappable<key_compare>::value &&
+ (!allocator_type::propagate_on_container_swap::value ||
+ __is_nothrow_swappable<allocator_type>::value));
+
+ // observers:
+ allocator_type get_allocator() const noexcept;
+ key_compare key_comp() const;
+ value_compare value_comp() const;
+
+ // set operations:
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ template<typename K>
+ iterator find(const K& x);
+ template<typename K>
+ const_iterator find(const K& x) const; // C++14
+
+ template<typename K>
+ size_type count(const K& x) const; // C++14
+ size_type count(const key_type& k) const;
+
+ bool contains(const key_type& x) const; // C++20
+ template<class K> bool contains(const K& x) const; // C++20
+
+ iterator lower_bound(const key_type& k);
+ const_iterator lower_bound(const key_type& k) const;
+ template<typename K>
+ iterator lower_bound(const K& x); // C++14
+ template<typename K>
+ const_iterator lower_bound(const K& x) const; // C++14
+
+ iterator upper_bound(const key_type& k);
+ const_iterator upper_bound(const key_type& k) const;
+ template<typename K>
+ iterator upper_bound(const K& x); // C++14
+ template<typename K>
+ const_iterator upper_bound(const K& x) const; // C++14
+
+ pair<iterator,iterator> equal_range(const key_type& k);
+ pair<const_iterator,const_iterator> equal_range(const key_type& k) const;
+ template<typename K>
+ pair<iterator,iterator> equal_range(const K& x); // C++14
+ template<typename K>
+ pair<const_iterator,const_iterator> equal_range(const K& x) const; // C++14
+};
+
+template <class InputIterator,
+ class Compare = less<typename iterator_traits<InputIterator>::value_type>,
+ class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+multiset(InputIterator, InputIterator,
+ Compare = Compare(), Allocator = Allocator())
+ -> multiset<typename iterator_traits<InputIterator>::value_type, Compare, Allocator>; // C++17
+
+template<ranges::input_range R, class Compare = less<ranges::range_value_t<R>>,
+ class Allocator = allocator<ranges::range_value_t<R>>>
+ multiset(from_range_t, R&&, Compare = Compare(), Allocator = Allocator())
+ -> multiset<ranges::range_value_t<R>, Compare, Allocator>;
+
+template<class Key, class Compare = less<Key>, class Allocator = allocator<Key>>
+multiset(initializer_list<Key>, Compare = Compare(), Allocator = Allocator())
+ -> multiset<Key, Compare, Allocator>; // C++17
+
+template<class InputIterator, class Allocator>
+multiset(InputIterator, InputIterator, Allocator)
+ -> multiset<typename iterator_traits<InputIterator>::value_type,
+ less<typename iterator_traits<InputIterator>::value_type>, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator>
+ multiset(from_range_t, R&&, Allocator)
+ -> multiset<ranges::range_value_t<R>, less<ranges::range_value_t<R>>, Allocator>;
+
+template<class Key, class Allocator>
+multiset(initializer_list<Key>, Allocator) -> multiset<Key, less<Key>, Allocator>; // C++17
+
+template <class Key, class Compare, class Allocator>
+bool
+operator==(const multiset<Key, Compare, Allocator>& x,
+ const multiset<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator< (const multiset<Key, Compare, Allocator>& x,
+ const multiset<Key, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class Compare, class Allocator>
+bool
+operator!=(const multiset<Key, Compare, Allocator>& x,
+ const multiset<Key, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class Compare, class Allocator>
+bool
+operator> (const multiset<Key, Compare, Allocator>& x,
+ const multiset<Key, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class Compare, class Allocator>
+bool
+operator>=(const multiset<Key, Compare, Allocator>& x,
+ const multiset<Key, Compare, Allocator>& y); // removed in C++20
+
+template <class Key, class Compare, class Allocator>
+bool
+operator<=(const multiset<Key, Compare, Allocator>& x,
+ const multiset<Key, Compare, Allocator>& y); // removed in C++20
+
+template<class Key, class Compare, class Allocator>
+ synth-three-way-result<Key> operator<=>(const multiset<Key, Compare, Allocator>& x,
+ const multiset<Key, Compare, Allocator>& y); // since C++20
+
+// specialized algorithms:
+template <class Key, class Compare, class Allocator>
+void
+swap(multiset<Key, Compare, Allocator>& x, multiset<Key, Compare, Allocator>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class Key, class Compare, class Allocator, class Predicate>
+typename multiset<Key, Compare, Allocator>::size_type
+erase_if(multiset<Key, Compare, Allocator>& c, Predicate pred); // C++20
+
+} // std
+
+*/
+
+#include <__algorithm/equal.h>
+#include <__algorithm/lexicographical_compare.h>
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__assert>
+#include <__config>
+#include <__functional/is_transparent.h>
+#include <__functional/operations.h>
+#include <__iterator/erase_if_container.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/ranges_iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__memory/allocator.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__node_handle>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__tree>
+#include <__type_traits/is_allocator.h>
+#include <__utility/forward.h>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [associative.set.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Key, class _Compare, class _Allocator>
+class multiset;
+
+template <class _Key, class _Compare = less<_Key>, class _Allocator = allocator<_Key> >
+class _LIBCPP_TEMPLATE_VIS set {
+public:
+ // types:
+ typedef _Key key_type;
+ typedef key_type value_type;
+ typedef __type_identity_t<_Compare> key_compare;
+ typedef key_compare value_compare;
+ typedef __type_identity_t<_Allocator> allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+
+ static_assert(is_same<typename allocator_type::value_type, value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+private:
+ typedef __tree<value_type, value_compare, allocator_type> __base;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+
+ __base __tree_;
+
+public:
+ typedef typename __base::pointer pointer;
+ typedef typename __base::const_pointer const_pointer;
+ typedef typename __base::size_type size_type;
+ typedef typename __base::difference_type difference_type;
+ typedef typename __base::const_iterator iterator;
+ typedef typename __base::const_iterator const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+#if _LIBCPP_STD_VER >= 17
+ typedef __set_node_handle<typename __base::__node, allocator_type> node_type;
+ typedef __insert_return_type<iterator, node_type> insert_return_type;
+#endif
+
+ template <class _Key2, class _Compare2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS set;
+ template <class _Key2, class _Compare2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS multiset;
+
+ _LIBCPP_HIDE_FROM_ABI set() _NOEXCEPT_(
+ is_nothrow_default_constructible<allocator_type>::value&& is_nothrow_default_constructible<key_compare>::value&&
+ is_nothrow_copy_constructible<key_compare>::value)
+ : __tree_(value_compare()) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit set(const value_compare& __comp) _NOEXCEPT_(
+ is_nothrow_default_constructible<allocator_type>::value&& is_nothrow_copy_constructible<key_compare>::value)
+ : __tree_(__comp) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit set(const value_compare& __comp, const allocator_type& __a) : __tree_(__comp, __a) {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI set(_InputIterator __f, _InputIterator __l, const value_compare& __comp = value_compare())
+ : __tree_(__comp) {
+ insert(__f, __l);
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ set(_InputIterator __f, _InputIterator __l, const value_compare& __comp, const allocator_type& __a)
+ : __tree_(__comp, __a) {
+ insert(__f, __l);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI
+ set(from_range_t,
+ _Range&& __range,
+ const key_compare& __comp = key_compare(),
+ const allocator_type& __a = allocator_type())
+ : __tree_(__comp, __a) {
+ insert_range(std::forward<_Range>(__range));
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI set(_InputIterator __f, _InputIterator __l, const allocator_type& __a)
+ : set(__f, __l, key_compare(), __a) {}
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI set(from_range_t, _Range&& __range, const allocator_type& __a)
+ : set(from_range, std::forward<_Range>(__range), key_compare(), __a) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI set(const set& __s) : __tree_(__s.__tree_) { insert(__s.begin(), __s.end()); }
+
+ _LIBCPP_HIDE_FROM_ABI set& operator=(const set& __s) {
+ __tree_ = __s.__tree_;
+ return *this;
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI set(set&& __s) noexcept(is_nothrow_move_constructible<__base>::value)
+ : __tree_(std::move(__s.__tree_)) {}
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI explicit set(const allocator_type& __a) : __tree_(__a) {}
+
+ _LIBCPP_HIDE_FROM_ABI set(const set& __s, const allocator_type& __a) : __tree_(__s.__tree_.value_comp(), __a) {
+ insert(__s.begin(), __s.end());
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI set(set&& __s, const allocator_type& __a);
+
+ _LIBCPP_HIDE_FROM_ABI set(initializer_list<value_type> __il, const value_compare& __comp = value_compare())
+ : __tree_(__comp) {
+ insert(__il.begin(), __il.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI set(initializer_list<value_type> __il, const value_compare& __comp, const allocator_type& __a)
+ : __tree_(__comp, __a) {
+ insert(__il.begin(), __il.end());
+ }
+
+# if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI set(initializer_list<value_type> __il, const allocator_type& __a)
+ : set(__il, key_compare(), __a) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI set& operator=(initializer_list<value_type> __il) {
+ __tree_.__assign_unique(__il.begin(), __il.end());
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI set& operator=(set&& __s) noexcept(is_nothrow_move_assignable<__base>::value) {
+ __tree_ = std::move(__s.__tree_);
+ return *this;
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI ~set() { static_assert(sizeof(__diagnose_non_const_comparator<_Key, _Compare>()), ""); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __tree_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __tree_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __tree_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __tree_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() _NOEXCEPT { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const _NOEXCEPT { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() _NOEXCEPT { return reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const _NOEXCEPT { return const_reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const _NOEXCEPT { return rbegin(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __tree_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __tree_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __tree_.max_size(); }
+
+ // modifiers:
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> emplace(_Args&&... __args) {
+ return __tree_.__emplace_unique(std::forward<_Args>(__args)...);
+ }
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator __p, _Args&&... __args) {
+ return __tree_.__emplace_hint_unique(__p, std::forward<_Args>(__args)...);
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(const value_type& __v) { return __tree_.__insert_unique(__v); }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __v) {
+ return __tree_.__insert_unique(__p, __v);
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __f, _InputIterator __l) {
+ for (const_iterator __e = cend(); __f != __l; ++__f)
+ __tree_.__insert_unique(__e, *__f);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ const_iterator __end = cend();
+ for (auto&& __element : __range) {
+ __tree_.__insert_unique(__end, std::forward<decltype(__element)>(__element));
+ }
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(value_type&& __v) {
+ return __tree_.__insert_unique(std::move(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __v) {
+ return __tree_.__insert_unique(__p, std::move(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p) { return __tree_.erase(__p); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __tree_.__erase_unique(__k); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __f, const_iterator __l) { return __tree_.erase(__f, __l); }
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __tree_.clear(); }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI insert_return_type insert(node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to set::insert()");
+ return __tree_.template __node_handle_insert_unique< node_type, insert_return_type>(std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to set::insert()");
+ return __tree_.template __node_handle_insert_unique<node_type>(__hint, std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(key_type const& __key) {
+ return __tree_.template __node_handle_extract<node_type>(__key);
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(const_iterator __it) {
+ return __tree_.template __node_handle_extract<node_type>(__it);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(set<key_type, _Compare2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_unique(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(set<key_type, _Compare2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_unique(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(multiset<key_type, _Compare2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_unique(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(multiset<key_type, _Compare2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_unique(__source.__tree_);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void swap(set& __s) _NOEXCEPT_(__is_nothrow_swappable_v<__base>) { __tree_.swap(__s.__tree_); }
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT { return __tree_.__alloc(); }
+ _LIBCPP_HIDE_FROM_ABI key_compare key_comp() const { return __tree_.value_comp(); }
+ _LIBCPP_HIDE_FROM_ABI value_compare value_comp() const { return __tree_.value_comp(); }
+
+ // set operations:
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __tree_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __tree_.find(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _K2& __k) {
+ return __tree_.find(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _K2& __k) const {
+ return __tree_.find(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __tree_.__count_unique(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _K2& __k) const {
+ return __tree_.__count_multi(__k);
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __k) const { return find(__k) != end(); }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _K2& __k) const {
+ return find(__k) != end();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const key_type& __k) { return __tree_.lower_bound(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const key_type& __k) const { return __tree_.lower_bound(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const _K2& __k) {
+ return __tree_.lower_bound(__k);
+ }
+
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const _K2& __k) const {
+ return __tree_.lower_bound(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const key_type& __k) { return __tree_.upper_bound(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const key_type& __k) const { return __tree_.upper_bound(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const _K2& __k) {
+ return __tree_.upper_bound(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const _K2& __k) const {
+ return __tree_.upper_bound(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __tree_.__equal_range_unique(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __tree_.__equal_range_unique(__k);
+ }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _K2& __k) {
+ return __tree_.__equal_range_multi(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _K2& __k) const {
+ return __tree_.__equal_range_multi(__k);
+ }
+#endif
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Compare = less<__iter_value_type<_InputIterator>>,
+ class _Allocator = allocator<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+set(_InputIterator, _InputIterator, _Compare = _Compare(), _Allocator = _Allocator())
+ -> set<__iter_value_type<_InputIterator>, _Compare, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Compare = less<ranges::range_value_t<_Range>>,
+ class _Allocator = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+set(from_range_t, _Range&&, _Compare = _Compare(), _Allocator = _Allocator())
+ -> set<ranges::range_value_t<_Range>, _Compare, _Allocator>;
+# endif
+
+template <class _Key,
+ class _Compare = less<_Key>,
+ class _Allocator = allocator<_Key>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+set(initializer_list<_Key>, _Compare = _Compare(), _Allocator = _Allocator()) -> set<_Key, _Compare, _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+set(_InputIterator,
+ _InputIterator,
+ _Allocator) -> set<__iter_value_type<_InputIterator>, less<__iter_value_type<_InputIterator>>, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+set(from_range_t,
+ _Range&&,
+ _Allocator) -> set<ranges::range_value_t<_Range>, less<ranges::range_value_t<_Range>>, _Allocator>;
+# endif
+
+template <class _Key, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+set(initializer_list<_Key>, _Allocator) -> set<_Key, less<_Key>, _Allocator>;
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Compare, class _Allocator>
+set<_Key, _Compare, _Allocator>::set(set&& __s, const allocator_type& __a) : __tree_(std::move(__s.__tree_), __a) {
+ if (__a != __s.get_allocator()) {
+ const_iterator __e = cend();
+ while (!__s.empty())
+ insert(__e, std::move(__s.__tree_.remove(__s.begin())->__value_));
+ }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const set<_Key, _Compare, _Allocator>& __x, const set<_Key, _Compare, _Allocator>& __y) {
+ return __x.size() == __y.size() && std::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const set<_Key, _Compare, _Allocator>& __x, const set<_Key, _Compare, _Allocator>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const set<_Key, _Compare, _Allocator>& __x, const set<_Key, _Compare, _Allocator>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const set<_Key, _Compare, _Allocator>& __x, const set<_Key, _Compare, _Allocator>& __y) {
+ return __y < __x;
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const set<_Key, _Compare, _Allocator>& __x, const set<_Key, _Compare, _Allocator>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const set<_Key, _Compare, _Allocator>& __x, const set<_Key, _Compare, _Allocator>& __y) {
+ return !(__y < __x);
+}
+
+#else // _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __synth_three_way_result<_Key>
+operator<=>(const set<_Key, _Allocator>& __x, const set<_Key, _Allocator>& __y) {
+ return std::lexicographical_compare_three_way(__x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+// specialized algorithms:
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void swap(set<_Key, _Compare, _Allocator>& __x, set<_Key, _Compare, _Allocator>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Key, class _Compare, class _Allocator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename set<_Key, _Compare, _Allocator>::size_type
+erase_if(set<_Key, _Compare, _Allocator>& __c, _Predicate __pred) {
+ return std::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+template <class _Key, class _Compare = less<_Key>, class _Allocator = allocator<_Key> >
+class _LIBCPP_TEMPLATE_VIS multiset {
+public:
+ // types:
+ typedef _Key key_type;
+ typedef key_type value_type;
+ typedef __type_identity_t<_Compare> key_compare;
+ typedef key_compare value_compare;
+ typedef __type_identity_t<_Allocator> allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+
+ static_assert(is_same<typename allocator_type::value_type, value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+private:
+ typedef __tree<value_type, value_compare, allocator_type> __base;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+
+ __base __tree_;
+
+public:
+ typedef typename __base::pointer pointer;
+ typedef typename __base::const_pointer const_pointer;
+ typedef typename __base::size_type size_type;
+ typedef typename __base::difference_type difference_type;
+ typedef typename __base::const_iterator iterator;
+ typedef typename __base::const_iterator const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+#if _LIBCPP_STD_VER >= 17
+ typedef __set_node_handle<typename __base::__node, allocator_type> node_type;
+#endif
+
+ template <class _Key2, class _Compare2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS set;
+ template <class _Key2, class _Compare2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS multiset;
+
+ // construct/copy/destroy:
+ _LIBCPP_HIDE_FROM_ABI multiset() _NOEXCEPT_(
+ is_nothrow_default_constructible<allocator_type>::value&& is_nothrow_default_constructible<key_compare>::value&&
+ is_nothrow_copy_constructible<key_compare>::value)
+ : __tree_(value_compare()) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit multiset(const value_compare& __comp) _NOEXCEPT_(
+ is_nothrow_default_constructible<allocator_type>::value&& is_nothrow_copy_constructible<key_compare>::value)
+ : __tree_(__comp) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit multiset(const value_compare& __comp, const allocator_type& __a)
+ : __tree_(__comp, __a) {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI multiset(_InputIterator __f, _InputIterator __l, const value_compare& __comp = value_compare())
+ : __tree_(__comp) {
+ insert(__f, __l);
+ }
+
+#if _LIBCPP_STD_VER >= 14
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI multiset(_InputIterator __f, _InputIterator __l, const allocator_type& __a)
+ : multiset(__f, __l, key_compare(), __a) {}
+#endif
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ multiset(_InputIterator __f, _InputIterator __l, const value_compare& __comp, const allocator_type& __a)
+ : __tree_(__comp, __a) {
+ insert(__f, __l);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI
+ multiset(from_range_t,
+ _Range&& __range,
+ const key_compare& __comp = key_compare(),
+ const allocator_type& __a = allocator_type())
+ : __tree_(__comp, __a) {
+ insert_range(std::forward<_Range>(__range));
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI multiset(from_range_t, _Range&& __range, const allocator_type& __a)
+ : multiset(from_range, std::forward<_Range>(__range), key_compare(), __a) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI multiset(const multiset& __s)
+ : __tree_(__s.__tree_.value_comp(),
+ __alloc_traits::select_on_container_copy_construction(__s.__tree_.__alloc())) {
+ insert(__s.begin(), __s.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI multiset& operator=(const multiset& __s) {
+ __tree_ = __s.__tree_;
+ return *this;
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI multiset(multiset&& __s) noexcept(is_nothrow_move_constructible<__base>::value)
+ : __tree_(std::move(__s.__tree_)) {}
+
+ _LIBCPP_HIDE_FROM_ABI multiset(multiset&& __s, const allocator_type& __a);
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI explicit multiset(const allocator_type& __a) : __tree_(__a) {}
+ _LIBCPP_HIDE_FROM_ABI multiset(const multiset& __s, const allocator_type& __a)
+ : __tree_(__s.__tree_.value_comp(), __a) {
+ insert(__s.begin(), __s.end());
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI multiset(initializer_list<value_type> __il, const value_compare& __comp = value_compare())
+ : __tree_(__comp) {
+ insert(__il.begin(), __il.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI
+ multiset(initializer_list<value_type> __il, const value_compare& __comp, const allocator_type& __a)
+ : __tree_(__comp, __a) {
+ insert(__il.begin(), __il.end());
+ }
+
+# if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI multiset(initializer_list<value_type> __il, const allocator_type& __a)
+ : multiset(__il, key_compare(), __a) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI multiset& operator=(initializer_list<value_type> __il) {
+ __tree_.__assign_multi(__il.begin(), __il.end());
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI multiset& operator=(multiset&& __s) _NOEXCEPT_(is_nothrow_move_assignable<__base>::value) {
+ __tree_ = std::move(__s.__tree_);
+ return *this;
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI ~multiset() { static_assert(sizeof(__diagnose_non_const_comparator<_Key, _Compare>()), ""); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __tree_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __tree_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __tree_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __tree_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() _NOEXCEPT { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const _NOEXCEPT { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() _NOEXCEPT { return reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const _NOEXCEPT { return const_reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const _NOEXCEPT { return rbegin(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __tree_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __tree_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __tree_.max_size(); }
+
+ // modifiers:
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace(_Args&&... __args) {
+ return __tree_.__emplace_multi(std::forward<_Args>(__args)...);
+ }
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator __p, _Args&&... __args) {
+ return __tree_.__emplace_hint_multi(__p, std::forward<_Args>(__args)...);
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const value_type& __v) { return __tree_.__insert_multi(__v); }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __v) {
+ return __tree_.__insert_multi(__p, __v);
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __f, _InputIterator __l) {
+ for (const_iterator __e = cend(); __f != __l; ++__f)
+ __tree_.__insert_multi(__e, *__f);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ const_iterator __end = cend();
+ for (auto&& __element : __range) {
+ __tree_.__insert_multi(__end, std::forward<decltype(__element)>(__element));
+ }
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI iterator insert(value_type&& __v) { return __tree_.__insert_multi(std::move(__v)); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __v) {
+ return __tree_.__insert_multi(__p, std::move(__v));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p) { return __tree_.erase(__p); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __tree_.__erase_multi(__k); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __f, const_iterator __l) { return __tree_.erase(__f, __l); }
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __tree_.clear(); }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI iterator insert(node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to multiset::insert()");
+ return __tree_.template __node_handle_insert_multi<node_type>(std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to multiset::insert()");
+ return __tree_.template __node_handle_insert_multi<node_type>(__hint, std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(key_type const& __key) {
+ return __tree_.template __node_handle_extract<node_type>(__key);
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(const_iterator __it) {
+ return __tree_.template __node_handle_extract<node_type>(__it);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(multiset<key_type, _Compare2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_multi(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(multiset<key_type, _Compare2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_multi(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(set<key_type, _Compare2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_multi(__source.__tree_);
+ }
+ template <class _Compare2>
+ _LIBCPP_HIDE_FROM_ABI void merge(set<key_type, _Compare2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __tree_.__node_handle_merge_multi(__source.__tree_);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void swap(multiset& __s) _NOEXCEPT_(__is_nothrow_swappable_v<__base>) {
+ __tree_.swap(__s.__tree_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT { return __tree_.__alloc(); }
+ _LIBCPP_HIDE_FROM_ABI key_compare key_comp() const { return __tree_.value_comp(); }
+ _LIBCPP_HIDE_FROM_ABI value_compare value_comp() const { return __tree_.value_comp(); }
+
+ // set operations:
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __tree_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __tree_.find(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _K2& __k) {
+ return __tree_.find(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _K2& __k) const {
+ return __tree_.find(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __tree_.__count_multi(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _K2& __k) const {
+ return __tree_.__count_multi(__k);
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __k) const { return find(__k) != end(); }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _K2& __k) const {
+ return find(__k) != end();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const key_type& __k) { return __tree_.lower_bound(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const key_type& __k) const { return __tree_.lower_bound(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const _K2& __k) {
+ return __tree_.lower_bound(__k);
+ }
+
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const _K2& __k) const {
+ return __tree_.lower_bound(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const key_type& __k) { return __tree_.upper_bound(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const key_type& __k) const { return __tree_.upper_bound(__k); }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const _K2& __k) {
+ return __tree_.upper_bound(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const _K2& __k) const {
+ return __tree_.upper_bound(__k);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __tree_.__equal_range_multi(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __tree_.__equal_range_multi(__k);
+ }
+#if _LIBCPP_STD_VER >= 14
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _K2& __k) {
+ return __tree_.__equal_range_multi(__k);
+ }
+ template <typename _K2, enable_if_t<__is_transparent_v<_Compare, _K2>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _K2& __k) const {
+ return __tree_.__equal_range_multi(__k);
+ }
+#endif
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Compare = less<__iter_value_type<_InputIterator>>,
+ class _Allocator = allocator<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+multiset(_InputIterator, _InputIterator, _Compare = _Compare(), _Allocator = _Allocator())
+ -> multiset<__iter_value_type<_InputIterator>, _Compare, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Compare = less<ranges::range_value_t<_Range>>,
+ class _Allocator = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+multiset(from_range_t, _Range&&, _Compare = _Compare(), _Allocator = _Allocator())
+ -> multiset<ranges::range_value_t<_Range>, _Compare, _Allocator>;
+# endif
+
+template <class _Key,
+ class _Compare = less<_Key>,
+ class _Allocator = allocator<_Key>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+ class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+multiset(initializer_list<_Key>,
+ _Compare = _Compare(),
+ _Allocator = _Allocator()) -> multiset<_Key, _Compare, _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value, void>,
+ class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multiset(_InputIterator, _InputIterator, _Allocator)
+ -> multiset<__iter_value_type<_InputIterator>, less<__iter_value_type<_InputIterator>>, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multiset(from_range_t,
+ _Range&&,
+ _Allocator) -> multiset<ranges::range_value_t<_Range>, less<ranges::range_value_t<_Range>>, _Allocator>;
+# endif
+
+template <class _Key, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multiset(initializer_list<_Key>, _Allocator) -> multiset<_Key, less<_Key>, _Allocator>;
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Compare, class _Allocator>
+multiset<_Key, _Compare, _Allocator>::multiset(multiset&& __s, const allocator_type& __a)
+ : __tree_(std::move(__s.__tree_), __a) {
+ if (__a != __s.get_allocator()) {
+ const_iterator __e = cend();
+ while (!__s.empty())
+ insert(__e, std::move(__s.__tree_.remove(__s.begin())->__value_));
+ }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const multiset<_Key, _Compare, _Allocator>& __x, const multiset<_Key, _Compare, _Allocator>& __y) {
+ return __x.size() == __y.size() && std::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const multiset<_Key, _Compare, _Allocator>& __x, const multiset<_Key, _Compare, _Allocator>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const multiset<_Key, _Compare, _Allocator>& __x, const multiset<_Key, _Compare, _Allocator>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const multiset<_Key, _Compare, _Allocator>& __x, const multiset<_Key, _Compare, _Allocator>& __y) {
+ return __y < __x;
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const multiset<_Key, _Compare, _Allocator>& __x, const multiset<_Key, _Compare, _Allocator>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const multiset<_Key, _Compare, _Allocator>& __x, const multiset<_Key, _Compare, _Allocator>& __y) {
+ return !(__y < __x);
+}
+
+#else // _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI __synth_three_way_result<_Key>
+operator<=>(const multiset<_Key, _Allocator>& __x, const multiset<_Key, _Allocator>& __y) {
+ return std::lexicographical_compare_three_way(
+ __x.begin(), __x.end(), __y.begin(), __y.end(), __synth_three_way);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(multiset<_Key, _Compare, _Allocator>& __x, multiset<_Key, _Compare, _Allocator>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Key, class _Compare, class _Allocator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename multiset<_Key, _Compare, _Allocator>::size_type
+erase_if(multiset<_Key, _Compare, _Allocator>& __c, _Predicate __pred) {
+ return std::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _KeyT, class _CompareT = std::less<_KeyT>>
+using set _LIBCPP_AVAILABILITY_PMR = std::set<_KeyT, _CompareT, polymorphic_allocator<_KeyT>>;
+
+template <class _KeyT, class _CompareT = std::less<_KeyT>>
+using multiset _LIBCPP_AVAILABILITY_PMR = std::multiset<_KeyT, _CompareT, polymorphic_allocator<_KeyT>>;
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <cstdlib>
+# include <functional>
+# include <iterator>
+# include <stdexcept>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_SET
diff --git a/libcxx/include/__cxx03/shared_mutex b/libcxx/include/__cxx03/shared_mutex
new file mode 100644
index 00000000000000..f63bd25493878b
--- /dev/null
+++ b/libcxx/include/__cxx03/shared_mutex
@@ -0,0 +1,464 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SHARED_MUTEX
+#define _LIBCPP_SHARED_MUTEX
+
+/*
+ shared_mutex synopsis
+
+// C++1y
+
+namespace std
+{
+
+class shared_mutex // C++17
+{
+public:
+ shared_mutex();
+ ~shared_mutex();
+
+ shared_mutex(const shared_mutex&) = delete;
+ shared_mutex& operator=(const shared_mutex&) = delete;
+
+ // Exclusive ownership
+ void lock(); // blocking
+ bool try_lock();
+ void unlock();
+
+ // Shared ownership
+ void lock_shared(); // blocking
+ bool try_lock_shared();
+ void unlock_shared();
+
+ typedef implementation-defined native_handle_type; // See 30.2.3
+ native_handle_type native_handle(); // See 30.2.3
+};
+
+class shared_timed_mutex
+{
+public:
+ shared_timed_mutex();
+ ~shared_timed_mutex();
+
+ shared_timed_mutex(const shared_timed_mutex&) = delete;
+ shared_timed_mutex& operator=(const shared_timed_mutex&) = delete;
+
+ // Exclusive ownership
+ void lock(); // blocking
+ bool try_lock();
+ template <class Rep, class Period>
+ bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
+ template <class Clock, class Duration>
+ bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
+ void unlock();
+
+ // Shared ownership
+ void lock_shared(); // blocking
+ bool try_lock_shared();
+ template <class Rep, class Period>
+ bool
+ try_lock_shared_for(const chrono::duration<Rep, Period>& rel_time);
+ template <class Clock, class Duration>
+ bool
+ try_lock_shared_until(const chrono::time_point<Clock, Duration>& abs_time);
+ void unlock_shared();
+};
+
+template <class Mutex>
+class shared_lock
+{
+public:
+ typedef Mutex mutex_type;
+
+ // Shared locking
+ shared_lock() noexcept;
+ explicit shared_lock(mutex_type& m); // blocking
+ shared_lock(mutex_type& m, defer_lock_t) noexcept;
+ shared_lock(mutex_type& m, try_to_lock_t);
+ shared_lock(mutex_type& m, adopt_lock_t);
+ template <class Clock, class Duration>
+ shared_lock(mutex_type& m,
+ const chrono::time_point<Clock, Duration>& abs_time);
+ template <class Rep, class Period>
+ shared_lock(mutex_type& m,
+ const chrono::duration<Rep, Period>& rel_time);
+ ~shared_lock();
+
+ shared_lock(shared_lock const&) = delete;
+ shared_lock& operator=(shared_lock const&) = delete;
+
+ shared_lock(shared_lock&& u) noexcept;
+ shared_lock& operator=(shared_lock&& u) noexcept;
+
+ void lock(); // blocking
+ bool try_lock();
+ template <class Rep, class Period>
+ bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
+ template <class Clock, class Duration>
+ bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
+ void unlock();
+
+ // Setters
+ void swap(shared_lock& u) noexcept;
+ mutex_type* release() noexcept;
+
+ // Getters
+ bool owns_lock() const noexcept;
+ explicit operator bool () const noexcept;
+ mutex_type* mutex() const noexcept;
+};
+
+template <class Mutex>
+ void swap(shared_lock<Mutex>& x, shared_lock<Mutex>& y) noexcept;
+
+} // std
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+# include <__chrono/duration.h>
+# include <__chrono/steady_clock.h>
+# include <__chrono/time_point.h>
+# include <__condition_variable/condition_variable.h>
+# include <__memory/addressof.h>
+# include <__mutex/mutex.h>
+# include <__mutex/tag_types.h>
+# include <__mutex/unique_lock.h>
+# include <__system_error/system_error.h>
+# include <__utility/swap.h>
+# include <cerrno>
+# include <version>
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+# if _LIBCPP_STD_VER >= 14
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct _LIBCPP_EXPORTED_FROM_ABI __shared_mutex_base {
+ mutex __mut_;
+ condition_variable __gate1_;
+ condition_variable __gate2_;
+ unsigned __state_;
+
+ static const unsigned __write_entered_ = 1U << (sizeof(unsigned) * __CHAR_BIT__ - 1);
+ static const unsigned __n_readers_ = ~__write_entered_;
+
+ __shared_mutex_base();
+ _LIBCPP_HIDE_FROM_ABI ~__shared_mutex_base() = default;
+
+ __shared_mutex_base(const __shared_mutex_base&) = delete;
+ __shared_mutex_base& operator=(const __shared_mutex_base&) = delete;
+
+ // Exclusive ownership
+ void lock(); // blocking
+ bool try_lock();
+ void unlock();
+
+ // Shared ownership
+ void lock_shared(); // blocking
+ bool try_lock_shared();
+ void unlock_shared();
+
+ // typedef implementation-defined native_handle_type; // See 30.2.3
+ // native_handle_type native_handle(); // See 30.2.3
+};
+
+# if _LIBCPP_STD_VER >= 17
+class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_THREAD_SAFETY_ANNOTATION(__capability__("shared_mutex")) shared_mutex {
+ __shared_mutex_base __base_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI shared_mutex() : __base_() {}
+ _LIBCPP_HIDE_FROM_ABI ~shared_mutex() = default;
+
+ shared_mutex(const shared_mutex&) = delete;
+ shared_mutex& operator=(const shared_mutex&) = delete;
+
+ // Exclusive ownership
+ _LIBCPP_HIDE_FROM_ABI void lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(__acquire_capability__()) {
+ return __base_.lock();
+ }
+ _LIBCPP_HIDE_FROM_ABI bool try_lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(__try_acquire_capability__(true)) {
+ return __base_.try_lock();
+ }
+ _LIBCPP_HIDE_FROM_ABI void unlock() _LIBCPP_THREAD_SAFETY_ANNOTATION(__release_capability__()) {
+ return __base_.unlock();
+ }
+
+ // Shared ownership
+ _LIBCPP_HIDE_FROM_ABI void lock_shared() _LIBCPP_THREAD_SAFETY_ANNOTATION(__acquire_shared_capability__()) {
+ return __base_.lock_shared();
+ }
+ _LIBCPP_HIDE_FROM_ABI bool try_lock_shared()
+ _LIBCPP_THREAD_SAFETY_ANNOTATION(__try_acquire_shared_capability__(true)) {
+ return __base_.try_lock_shared();
+ }
+ _LIBCPP_HIDE_FROM_ABI void unlock_shared() _LIBCPP_THREAD_SAFETY_ANNOTATION(__release_shared_capability__()) {
+ return __base_.unlock_shared();
+ }
+
+ // typedef __shared_mutex_base::native_handle_type native_handle_type;
+ // _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() { return __base::unlock_shared(); }
+};
+# endif
+
+class _LIBCPP_EXPORTED_FROM_ABI
+_LIBCPP_THREAD_SAFETY_ANNOTATION(__capability__("shared_timed_mutex")) shared_timed_mutex {
+ __shared_mutex_base __base_;
+
+public:
+ shared_timed_mutex();
+ _LIBCPP_HIDE_FROM_ABI ~shared_timed_mutex() = default;
+
+ shared_timed_mutex(const shared_timed_mutex&) = delete;
+ shared_timed_mutex& operator=(const shared_timed_mutex&) = delete;
+
+ // Exclusive ownership
+ void lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(__acquire_capability__());
+ bool try_lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(__try_acquire_capability__(true));
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI bool try_lock_for(const chrono::duration<_Rep, _Period>& __rel_time)
+ _LIBCPP_THREAD_SAFETY_ANNOTATION(__try_acquire_capability__(true)) {
+ return try_lock_until(chrono::steady_clock::now() + __rel_time);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS bool
+ try_lock_until(const chrono::time_point<_Clock, _Duration>& __abs_time)
+ _LIBCPP_THREAD_SAFETY_ANNOTATION(__try_acquire_capability__(true));
+ void unlock() _LIBCPP_THREAD_SAFETY_ANNOTATION(__release_capability__());
+
+ // Shared ownership
+ void lock_shared() _LIBCPP_THREAD_SAFETY_ANNOTATION(__acquire_shared_capability__());
+ bool try_lock_shared() _LIBCPP_THREAD_SAFETY_ANNOTATION(__try_acquire_shared_capability__(true));
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI bool try_lock_shared_for(const chrono::duration<_Rep, _Period>& __rel_time)
+ _LIBCPP_THREAD_SAFETY_ANNOTATION(__try_acquire_shared_capability__(true)) {
+ return try_lock_shared_until(chrono::steady_clock::now() + __rel_time);
+ }
+ template <class _Clock, class _Duration>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS bool
+ try_lock_shared_until(const chrono::time_point<_Clock, _Duration>& __abs_time)
+ _LIBCPP_THREAD_SAFETY_ANNOTATION(__try_acquire_shared_capability__(true));
+ void unlock_shared() _LIBCPP_THREAD_SAFETY_ANNOTATION(__release_shared_capability__());
+};
+
+template <class _Clock, class _Duration>
+bool shared_timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __abs_time) {
+ unique_lock<mutex> __lk(__base_.__mut_);
+ if (__base_.__state_ & __base_.__write_entered_) {
+ while (true) {
+ cv_status __status = __base_.__gate1_.wait_until(__lk, __abs_time);
+ if ((__base_.__state_ & __base_.__write_entered_) == 0)
+ break;
+ if (__status == cv_status::timeout)
+ return false;
+ }
+ }
+ __base_.__state_ |= __base_.__write_entered_;
+ if (__base_.__state_ & __base_.__n_readers_) {
+ while (true) {
+ cv_status __status = __base_.__gate2_.wait_until(__lk, __abs_time);
+ if ((__base_.__state_ & __base_.__n_readers_) == 0)
+ break;
+ if (__status == cv_status::timeout) {
+ __base_.__state_ &= ~__base_.__write_entered_;
+ __base_.__gate1_.notify_all();
+ return false;
+ }
+ }
+ }
+ return true;
+}
+
+template <class _Clock, class _Duration>
+bool shared_timed_mutex::try_lock_shared_until(const chrono::time_point<_Clock, _Duration>& __abs_time) {
+ unique_lock<mutex> __lk(__base_.__mut_);
+ if ((__base_.__state_ & __base_.__write_entered_) ||
+ (__base_.__state_ & __base_.__n_readers_) == __base_.__n_readers_) {
+ while (true) {
+ cv_status __status = __base_.__gate1_.wait_until(__lk, __abs_time);
+ if ((__base_.__state_ & __base_.__write_entered_) == 0 &&
+ (__base_.__state_ & __base_.__n_readers_) < __base_.__n_readers_)
+ break;
+ if (__status == cv_status::timeout)
+ return false;
+ }
+ }
+ unsigned __num_readers = (__base_.__state_ & __base_.__n_readers_) + 1;
+ __base_.__state_ &= ~__base_.__n_readers_;
+ __base_.__state_ |= __num_readers;
+ return true;
+}
+
+template <class _Mutex>
+class shared_lock {
+public:
+ typedef _Mutex mutex_type;
+
+private:
+ mutex_type* __m_;
+ bool __owns_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI shared_lock() _NOEXCEPT : __m_(nullptr), __owns_(false) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit shared_lock(mutex_type& __m) : __m_(std::addressof(__m)), __owns_(true) {
+ __m_->lock_shared();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI shared_lock(mutex_type& __m, defer_lock_t) _NOEXCEPT
+ : __m_(std::addressof(__m)),
+ __owns_(false) {}
+
+ _LIBCPP_HIDE_FROM_ABI shared_lock(mutex_type& __m, try_to_lock_t)
+ : __m_(std::addressof(__m)), __owns_(__m.try_lock_shared()) {}
+
+ _LIBCPP_HIDE_FROM_ABI shared_lock(mutex_type& __m, adopt_lock_t) : __m_(std::addressof(__m)), __owns_(true) {}
+
+ template <class _Clock, class _Duration>
+ _LIBCPP_HIDE_FROM_ABI shared_lock(mutex_type& __m, const chrono::time_point<_Clock, _Duration>& __abs_time)
+ : __m_(std::addressof(__m)), __owns_(__m.try_lock_shared_until(__abs_time)) {}
+
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI shared_lock(mutex_type& __m, const chrono::duration<_Rep, _Period>& __rel_time)
+ : __m_(std::addressof(__m)), __owns_(__m.try_lock_shared_for(__rel_time)) {}
+
+ _LIBCPP_HIDE_FROM_ABI ~shared_lock() {
+ if (__owns_)
+ __m_->unlock_shared();
+ }
+
+ shared_lock(shared_lock const&) = delete;
+ shared_lock& operator=(shared_lock const&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI shared_lock(shared_lock&& __u) _NOEXCEPT : __m_(__u.__m_), __owns_(__u.__owns_) {
+ __u.__m_ = nullptr;
+ __u.__owns_ = false;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI shared_lock& operator=(shared_lock&& __u) _NOEXCEPT {
+ if (__owns_)
+ __m_->unlock_shared();
+ __m_ = nullptr;
+ __owns_ = false;
+ __m_ = __u.__m_;
+ __owns_ = __u.__owns_;
+ __u.__m_ = nullptr;
+ __u.__owns_ = false;
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void lock();
+ _LIBCPP_HIDE_FROM_ABI bool try_lock();
+ template <class _Rep, class _Period>
+ _LIBCPP_HIDE_FROM_ABI bool try_lock_for(const chrono::duration<_Rep, _Period>& __rel_time);
+ template <class _Clock, class _Duration>
+ _LIBCPP_HIDE_FROM_ABI bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __abs_time);
+ _LIBCPP_HIDE_FROM_ABI void unlock();
+
+ // Setters
+ _LIBCPP_HIDE_FROM_ABI void swap(shared_lock& __u) _NOEXCEPT {
+ std::swap(__m_, __u.__m_);
+ std::swap(__owns_, __u.__owns_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI mutex_type* release() _NOEXCEPT {
+ mutex_type* __m = __m_;
+ __m_ = nullptr;
+ __owns_ = false;
+ return __m;
+ }
+
+ // Getters
+ _LIBCPP_HIDE_FROM_ABI bool owns_lock() const _NOEXCEPT { return __owns_; }
+
+ _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return __owns_; }
+
+ _LIBCPP_HIDE_FROM_ABI mutex_type* mutex() const _NOEXCEPT { return __m_; }
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(shared_lock);
+
+template <class _Mutex>
+void shared_lock<_Mutex>::lock() {
+ if (__m_ == nullptr)
+ __throw_system_error(EPERM, "shared_lock::lock: references null mutex");
+ if (__owns_)
+ __throw_system_error(EDEADLK, "shared_lock::lock: already locked");
+ __m_->lock_shared();
+ __owns_ = true;
+}
+
+template <class _Mutex>
+bool shared_lock<_Mutex>::try_lock() {
+ if (__m_ == nullptr)
+ __throw_system_error(EPERM, "shared_lock::try_lock: references null mutex");
+ if (__owns_)
+ __throw_system_error(EDEADLK, "shared_lock::try_lock: already locked");
+ __owns_ = __m_->try_lock_shared();
+ return __owns_;
+}
+
+template <class _Mutex>
+template <class _Rep, class _Period>
+bool shared_lock<_Mutex>::try_lock_for(const chrono::duration<_Rep, _Period>& __d) {
+ if (__m_ == nullptr)
+ __throw_system_error(EPERM, "shared_lock::try_lock_for: references null mutex");
+ if (__owns_)
+ __throw_system_error(EDEADLK, "shared_lock::try_lock_for: already locked");
+ __owns_ = __m_->try_lock_shared_for(__d);
+ return __owns_;
+}
+
+template <class _Mutex>
+template <class _Clock, class _Duration>
+bool shared_lock<_Mutex>::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) {
+ if (__m_ == nullptr)
+ __throw_system_error(EPERM, "shared_lock::try_lock_until: references null mutex");
+ if (__owns_)
+ __throw_system_error(EDEADLK, "shared_lock::try_lock_until: already locked");
+ __owns_ = __m_->try_lock_shared_until(__t);
+ return __owns_;
+}
+
+template <class _Mutex>
+void shared_lock<_Mutex>::unlock() {
+ if (!__owns_)
+ __throw_system_error(EPERM, "shared_lock::unlock: not locked");
+ __m_->unlock_shared();
+ __owns_ = false;
+}
+
+template <class _Mutex>
+inline _LIBCPP_HIDE_FROM_ABI void swap(shared_lock<_Mutex>& __x, shared_lock<_Mutex>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+# endif // _LIBCPP_STD_VER >= 14
+
+_LIBCPP_POP_MACROS
+
+#endif // !defined(_LIBCPP_HAS_NO_THREADS)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <system_error>
+#endif
+
+#endif // _LIBCPP_SHARED_MUTEX
diff --git a/libcxx/include/__cxx03/source_location b/libcxx/include/__cxx03/source_location
new file mode 100644
index 00000000000000..d16e3c46fce55e
--- /dev/null
+++ b/libcxx/include/__cxx03/source_location
@@ -0,0 +1,85 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SOURCE_LOCATION
+#define _LIBCPP_SOURCE_LOCATION
+
+/* source_location synopsis
+
+namespace std {
+ struct source_location {
+ static consteval source_location current() noexcept;
+ constexpr source_location() noexcept;
+
+ constexpr uint_least32_t line() const noexcept;
+ constexpr uint_least32_t column() const noexcept;
+ constexpr const char* file_name() const noexcept;
+ constexpr const char* function_name() const noexcept;
+ };
+}
+*/
+
+#include <__config>
+#include <cstdint>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+class source_location {
+ // The names source_location::__impl, _M_file_name, _M_function_name, _M_line, and _M_column
+ // are hard-coded in the compiler and must not be changed here.
+ struct __impl {
+ const char* _M_file_name;
+ const char* _M_function_name;
+ unsigned _M_line;
+ unsigned _M_column;
+ };
+ const __impl* __ptr_ = nullptr;
+ // GCC returns the type 'const void*' from the builtin, while clang returns
+ // `const __impl*`. Per C++ [expr.const], casts from void* are not permitted
+ // in constant evaluation, so we don't want to use `void*` as the argument
+ // type unless the builtin returned that, anyhow, and the invalid cast is
+ // unavoidable.
+ using __bsl_ty = decltype(__builtin_source_location());
+
+public:
+ // The defaulted __ptr argument is necessary so that the builtin is evaluated
+ // in the context of the caller. An explicit value should never be provided.
+ static consteval source_location current(__bsl_ty __ptr = __builtin_source_location()) noexcept {
+ source_location __sl;
+ __sl.__ptr_ = static_cast<const __impl*>(__ptr);
+ return __sl;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr source_location() noexcept = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr uint_least32_t line() const noexcept {
+ return __ptr_ != nullptr ? __ptr_->_M_line : 0;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr uint_least32_t column() const noexcept {
+ return __ptr_ != nullptr ? __ptr_->_M_column : 0;
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr const char* file_name() const noexcept {
+ return __ptr_ != nullptr ? __ptr_->_M_file_name : "";
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr const char* function_name() const noexcept {
+ return __ptr_ != nullptr ? __ptr_->_M_function_name : "";
+ }
+};
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_SOURCE_LOCATION
diff --git a/libcxx/include/__cxx03/span b/libcxx/include/__cxx03/span
new file mode 100644
index 00000000000000..da631cdc3f90e6
--- /dev/null
+++ b/libcxx/include/__cxx03/span
@@ -0,0 +1,636 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SPAN
+#define _LIBCPP_SPAN
+
+/*
+ span synopsis
+
+namespace std {
+
+// constants
+inline constexpr size_t dynamic_extent = numeric_limits<size_t>::max();
+
+template<class T>
+ concept integral-constant-like = // exposition only, since C++26
+ is_integral_v<decltype(T::value)> &&
+ !is_same_v<bool, remove_const_t<decltype(T::value)>> &&
+ convertible_to<T, decltype(T::value)> &&
+ equality_comparable_with<T, decltype(T::value)> &&
+ bool_constant<T() == T::value>::value &&
+ bool_constant<static_cast<decltype(T::value)>(T()) == T::value>::value;
+
+template<class T>
+ constexpr size_t maybe-static-ext = dynamic_extent; // exposition only, since C++26
+template<integral-constant-like T>
+ constexpr size_t maybe-static-ext<T> = {T::value};
+
+// [views.span], class template span
+template <class ElementType, size_t Extent = dynamic_extent>
+ class span;
+
+template<class ElementType, size_t Extent>
+ inline constexpr bool ranges::enable_view<span<ElementType, Extent>> = true;
+
+template<class ElementType, size_t Extent>
+ inline constexpr bool ranges::enable_borrowed_range<span<ElementType, Extent>> = true;
+
+// [span.objectrep], views of object representation
+template <class ElementType, size_t Extent>
+ span<const byte, ((Extent == dynamic_extent) ? dynamic_extent :
+ (sizeof(ElementType) * Extent))> as_bytes(span<ElementType, Extent> s) noexcept;
+
+template <class ElementType, size_t Extent>
+ span< byte, ((Extent == dynamic_extent) ? dynamic_extent :
+ (sizeof(ElementType) * Extent))> as_writable_bytes(span<ElementType, Extent> s) noexcept;
+
+
+template <class ElementType, size_t Extent = dynamic_extent>
+class span {
+public:
+ // constants and types
+ using element_type = ElementType;
+ using value_type = remove_cv_t<ElementType>;
+ using size_type = size_t;
+ using difference_type = ptrdiff_t;
+ using pointer = element_type*;
+ using const_pointer = const element_type*;
+ using reference = element_type&;
+ using const_reference = const element_type&;
+ using iterator = implementation-defined;
+ using reverse_iterator = std::reverse_iterator<iterator>;
+ static constexpr size_type extent = Extent;
+
+ // [span.cons], span constructors, copy, assignment, and destructor
+ constexpr span() noexcept;
+ template <class It>
+ constexpr explicit(Extent != dynamic_extent) span(It first, size_type count);
+ template <class It, class End>
+ constexpr explicit(Extent != dynamic_extent) span(It first, End last);
+ template <size_t N>
+ constexpr span(type_identity_t<element_type> (&arr)[N]) noexcept;
+ template <size_t N>
+ constexpr span(array<value_type, N>& arr) noexcept;
+ template <size_t N>
+ constexpr span(const array<value_type, N>& arr) noexcept;
+ template<class R>
+ constexpr explicit(Extent != dynamic_extent) span(R&& r);
+ constexpr explicit(extent != dynamic_extent) span(std::initializer_list<value_type> il); // Since C++26
+ constexpr span(const span& other) noexcept = default;
+ template <class OtherElementType, size_t OtherExtent>
+ constexpr explicit(Extent != dynamic_extent) span(const span<OtherElementType, OtherExtent>& s) noexcept;
+ constexpr span& operator=(const span& other) noexcept = default;
+
+ // [span.sub], span subviews
+ template <size_t Count>
+ constexpr span<element_type, Count> first() const;
+ template <size_t Count>
+ constexpr span<element_type, Count> last() const;
+ template <size_t Offset, size_t Count = dynamic_extent>
+ constexpr span<element_type, see below> subspan() const;
+
+ constexpr span<element_type, dynamic_extent> first(size_type count) const;
+ constexpr span<element_type, dynamic_extent> last(size_type count) const;
+ constexpr span<element_type, dynamic_extent> subspan(size_type offset, size_type count = dynamic_extent) const;
+
+ // [span.obs], span observers
+ constexpr size_type size() const noexcept;
+ constexpr size_type size_bytes() const noexcept;
+ [[nodiscard]] constexpr bool empty() const noexcept;
+
+ // [span.elem], span element access
+ constexpr reference operator[](size_type idx) const;
+ constexpr reference at(size_type idx) const; // since C++26
+ constexpr reference front() const;
+ constexpr reference back() const;
+ constexpr pointer data() const noexcept;
+
+ // [span.iterators], span iterator support
+ constexpr iterator begin() const noexcept;
+ constexpr iterator end() const noexcept;
+ constexpr reverse_iterator rbegin() const noexcept;
+ constexpr reverse_iterator rend() const noexcept;
+
+private:
+ pointer data_; // exposition only
+ size_type size_; // exposition only
+};
+
+template<class It, class EndOrSize>
+ span(It, EndOrSize) -> span<remove_reference_t<iter_reference_t<_It>>>; // until C++26
+template<class It, class EndOrSize>
+ span(It, EndOrSize) -> span<remove_reference_t<iter_reference_t<It>>, maybe-static-ext<EndOrSize>>; // since C++26
+
+template<class T, size_t N>
+ span(T (&)[N]) -> span<T, N>;
+
+template<class T, size_t N>
+ span(array<T, N>&) -> span<T, N>;
+
+template<class T, size_t N>
+ span(const array<T, N>&) -> span<const T, N>;
+
+template<class R>
+ span(R&&) -> span<remove_reference_t<ranges::range_reference_t<R>>>;
+
+} // namespace std
+
+*/
+
+#include <__assert>
+#include <__concepts/convertible_to.h>
+#include <__concepts/equality_comparable.h>
+#include <__config>
+#include <__fwd/array.h>
+#include <__fwd/span.h>
+#include <__iterator/bounded_iter.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__iterator/wrap_iter.h>
+#include <__memory/pointer_traits.h>
+#include <__ranges/concepts.h>
+#include <__ranges/data.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/enable_view.h>
+#include <__ranges/size.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/forward.h>
+#include <cstddef> // for byte
+#include <initializer_list>
+#include <stdexcept>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp>
+struct __is_std_span : false_type {};
+
+template <class _Tp, size_t _Sz>
+struct __is_std_span<span<_Tp, _Sz>> : true_type {};
+
+template <class _Range, class _ElementType>
+concept __span_compatible_range =
+ !__is_std_span<remove_cvref_t<_Range>>::value && //
+ ranges::contiguous_range<_Range> && //
+ ranges::sized_range<_Range> && //
+ (ranges::borrowed_range<_Range> || is_const_v<_ElementType>) && //
+ !__is_std_array<remove_cvref_t<_Range>>::value && //
+ !is_array_v<remove_cvref_t<_Range>> && //
+ is_convertible_v<remove_reference_t<ranges::range_reference_t<_Range>> (*)[], _ElementType (*)[]>;
+
+template <class _From, class _To>
+concept __span_array_convertible = is_convertible_v<_From (*)[], _To (*)[]>;
+
+template <class _It, class _Tp>
+concept __span_compatible_iterator =
+ contiguous_iterator<_It> && __span_array_convertible<remove_reference_t<iter_reference_t<_It>>, _Tp>;
+
+template <class _Sentinel, class _It>
+concept __span_compatible_sentinel_for = sized_sentinel_for<_Sentinel, _It> && !is_convertible_v<_Sentinel, size_t>;
+
+template <typename _Tp, size_t _Extent>
+class _LIBCPP_TEMPLATE_VIS span {
+public:
+ // constants and types
+ using element_type = _Tp;
+ using value_type = remove_cv_t<_Tp>;
+ using size_type = size_t;
+ using difference_type = ptrdiff_t;
+ using pointer = _Tp*;
+ using const_pointer = const _Tp*;
+ using reference = _Tp&;
+ using const_reference = const _Tp&;
+# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
+ using iterator = __bounded_iter<pointer>;
+# else
+ using iterator = __wrap_iter<pointer>;
+# endif
+ using reverse_iterator = std::reverse_iterator<iterator>;
+
+ static constexpr size_type extent = _Extent;
+
+ // [span.cons], span constructors, copy, assignment, and destructor
+ template <size_t _Sz = _Extent>
+ requires(_Sz == 0)
+ _LIBCPP_HIDE_FROM_ABI constexpr span() noexcept : __data_{nullptr} {}
+
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit span(std::initializer_list<value_type> __il)
+ requires is_const_v<element_type>
+ : __data_{__il.begin()} {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(
+ _Extent == __il.size(), "Size mismatch in span's constructor _Extent != __il.size().");
+ }
+# endif
+
+ constexpr span(const span&) noexcept = default;
+ constexpr span& operator=(const span&) noexcept = default;
+
+ template <__span_compatible_iterator<element_type> _It>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_It __first, size_type __count) : __data_{std::to_address(__first)} {
+ (void)__count;
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Extent == __count, "size mismatch in span's constructor (iterator, len)");
+ }
+
+ template <__span_compatible_iterator<element_type> _It, __span_compatible_sentinel_for<_It> _End>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_It __first, _End __last) : __data_{std::to_address(__first)} {
+ // [span.cons]/10
+ // Throws: When and what last - first throws.
+ [[maybe_unused]] auto __dist = __last - __first;
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__dist >= 0, "invalid range in span's constructor (iterator, sentinel)");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __dist == _Extent, "invalid range in span's constructor (iterator, sentinel): last - first != extent");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr span(type_identity_t<element_type> (&__arr)[_Extent]) noexcept : __data_{__arr} {}
+
+ template <__span_array_convertible<element_type> _OtherElementType>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(array<_OtherElementType, _Extent>& __arr) noexcept : __data_{__arr.data()} {}
+
+ template <class _OtherElementType>
+ requires __span_array_convertible<const _OtherElementType, element_type>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(const array<_OtherElementType, _Extent>& __arr) noexcept
+ : __data_{__arr.data()} {}
+
+ template <__span_compatible_range<element_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_Range&& __r) : __data_{ranges::data(__r)} {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(ranges::size(__r) == _Extent, "size mismatch in span's constructor (range)");
+ }
+
+ template <__span_array_convertible<element_type> _OtherElementType>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(const span<_OtherElementType, _Extent>& __other) noexcept
+ : __data_{__other.data()} {}
+
+ template <__span_array_convertible<element_type> _OtherElementType>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit span(const span<_OtherElementType, dynamic_extent>& __other) noexcept
+ : __data_{__other.data()} {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Extent == __other.size(), "size mismatch in span's constructor (other span)");
+ }
+
+ template <size_t _Count>
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> first() const noexcept {
+ static_assert(_Count <= _Extent, "span<T, N>::first<Count>(): Count out of range");
+ return span<element_type, _Count>{data(), _Count};
+ }
+
+ template <size_t _Count>
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> last() const noexcept {
+ static_assert(_Count <= _Extent, "span<T, N>::last<Count>(): Count out of range");
+ return span<element_type, _Count>{data() + size() - _Count, _Count};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> first(size_type __count) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T, N>::first(count): count out of range");
+ return {data(), __count};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> last(size_type __count) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T, N>::last(count): count out of range");
+ return {data() + size() - __count, __count};
+ }
+
+ template <size_t _Offset, size_t _Count = dynamic_extent>
+ _LIBCPP_HIDE_FROM_ABI constexpr auto
+ subspan() const noexcept -> span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset> {
+ static_assert(_Offset <= _Extent, "span<T, N>::subspan<Offset, Count>(): Offset out of range");
+ static_assert(_Count == dynamic_extent || _Count <= _Extent - _Offset,
+ "span<T, N>::subspan<Offset, Count>(): Offset + Count out of range");
+
+ using _ReturnType = span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset>;
+ return _ReturnType{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent>
+ subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__offset <= size(), "span<T, N>::subspan(offset, count): offset out of range");
+ if (__count == dynamic_extent)
+ return {data() + __offset, size() - __offset};
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __count <= size() - __offset, "span<T, N>::subspan(offset, count): offset + count out of range");
+ return {data() + __offset, __count};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept { return _Extent; }
+ _LIBCPP_HIDE_FROM_ABI constexpr size_type size_bytes() const noexcept { return _Extent * sizeof(element_type); }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept { return _Extent == 0; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](size_type __idx) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx < size(), "span<T, N>::operator[](index): index out of range");
+ return __data_[__idx];
+ }
+
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI constexpr reference at(size_type __index) const {
+ if (__index >= size())
+ std::__throw_out_of_range("span");
+ return __data_[__index];
+ }
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference front() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T, N>::front() on empty span");
+ return __data_[0];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference back() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T, N>::back() on empty span");
+ return __data_[size() - 1];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr pointer data() const noexcept { return __data_; }
+
+ // [span.iter], span iterator support
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() const noexcept {
+# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
+ return std::__make_bounded_iter(data(), data(), data() + size());
+# else
+ return iterator(data());
+# endif
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator end() const noexcept {
+# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
+ return std::__make_bounded_iter(data() + size(), data(), data() + size());
+# else
+ return iterator(data() + size());
+# endif
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI span<const byte, _Extent * sizeof(element_type)> __as_bytes() const noexcept {
+ return span<const byte, _Extent * sizeof(element_type)>{reinterpret_cast<const byte*>(data()), size_bytes()};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI span<byte, _Extent * sizeof(element_type)> __as_writable_bytes() const noexcept {
+ return span<byte, _Extent * sizeof(element_type)>{reinterpret_cast<byte*>(data()), size_bytes()};
+ }
+
+private:
+ pointer __data_;
+};
+
+template <typename _Tp>
+class _LIBCPP_TEMPLATE_VIS span<_Tp, dynamic_extent> {
+public:
+ // constants and types
+ using element_type = _Tp;
+ using value_type = remove_cv_t<_Tp>;
+ using size_type = size_t;
+ using difference_type = ptrdiff_t;
+ using pointer = _Tp*;
+ using const_pointer = const _Tp*;
+ using reference = _Tp&;
+ using const_reference = const _Tp&;
+# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
+ using iterator = __bounded_iter<pointer>;
+# else
+ using iterator = __wrap_iter<pointer>;
+# endif
+ using reverse_iterator = std::reverse_iterator<iterator>;
+
+ static constexpr size_type extent = dynamic_extent;
+
+ // [span.cons], span constructors, copy, assignment, and destructor
+ _LIBCPP_HIDE_FROM_ABI constexpr span() noexcept : __data_{nullptr}, __size_{0} {}
+
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI constexpr span(std::initializer_list<value_type> __il)
+ requires is_const_v<element_type>
+ : __data_{__il.begin()}, __size_{__il.size()} {}
+# endif
+
+ constexpr span(const span&) noexcept = default;
+ constexpr span& operator=(const span&) noexcept = default;
+
+ template <__span_compatible_iterator<element_type> _It>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(_It __first, size_type __count)
+ : __data_{std::to_address(__first)}, __size_{__count} {}
+
+ template <__span_compatible_iterator<element_type> _It, __span_compatible_sentinel_for<_It> _End>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(_It __first, _End __last)
+ : __data_(std::to_address(__first)), __size_(__last - __first) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__last - __first >= 0, "invalid range in span's constructor (iterator, sentinel)");
+ }
+
+ template <size_t _Sz>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(type_identity_t<element_type> (&__arr)[_Sz]) noexcept
+ : __data_{__arr}, __size_{_Sz} {}
+
+ template <__span_array_convertible<element_type> _OtherElementType, size_t _Sz>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(array<_OtherElementType, _Sz>& __arr) noexcept
+ : __data_{__arr.data()}, __size_{_Sz} {}
+
+ template <class _OtherElementType, size_t _Sz>
+ requires __span_array_convertible<const _OtherElementType, element_type>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(const array<_OtherElementType, _Sz>& __arr) noexcept
+ : __data_{__arr.data()}, __size_{_Sz} {}
+
+ template <__span_compatible_range<element_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(_Range&& __r) : __data_(ranges::data(__r)), __size_{ranges::size(__r)} {}
+
+ template <__span_array_convertible<element_type> _OtherElementType, size_t _OtherExtent>
+ _LIBCPP_HIDE_FROM_ABI constexpr span(const span<_OtherElementType, _OtherExtent>& __other) noexcept
+ : __data_{__other.data()}, __size_{__other.size()} {}
+
+ template <size_t _Count>
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> first() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count <= size(), "span<T>::first<Count>(): Count out of range");
+ return span<element_type, _Count>{data(), _Count};
+ }
+
+ template <size_t _Count>
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> last() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count <= size(), "span<T>::last<Count>(): Count out of range");
+ return span<element_type, _Count>{data() + size() - _Count, _Count};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> first(size_type __count) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T>::first(count): count out of range");
+ return {data(), __count};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> last(size_type __count) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T>::last(count): count out of range");
+ return {data() + size() - __count, __count};
+ }
+
+ template <size_t _Offset, size_t _Count = dynamic_extent>
+ _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> subspan() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Offset <= size(), "span<T>::subspan<Offset, Count>(): Offset out of range");
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count == dynamic_extent || _Count <= size() - _Offset,
+ "span<T>::subspan<Offset, Count>(): Offset + Count out of range");
+ return span<element_type, _Count>{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count};
+ }
+
+ constexpr span<element_type, dynamic_extent> _LIBCPP_HIDE_FROM_ABI
+ subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__offset <= size(), "span<T>::subspan(offset, count): offset out of range");
+ if (__count == dynamic_extent)
+ return {data() + __offset, size() - __offset};
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __count <= size() - __offset, "span<T>::subspan(offset, count): offset + count out of range");
+ return {data() + __offset, __count};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept { return __size_; }
+ _LIBCPP_HIDE_FROM_ABI constexpr size_type size_bytes() const noexcept { return __size_ * sizeof(element_type); }
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept { return __size_ == 0; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](size_type __idx) const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx < size(), "span<T>::operator[](index): index out of range");
+ return __data_[__idx];
+ }
+
+# if _LIBCPP_STD_VER >= 26
+ _LIBCPP_HIDE_FROM_ABI constexpr reference at(size_type __index) const {
+ if (__index >= size())
+ std::__throw_out_of_range("span");
+ return __data_[__index];
+ }
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference front() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T>::front() on empty span");
+ return __data_[0];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference back() const noexcept {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T>::back() on empty span");
+ return __data_[size() - 1];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr pointer data() const noexcept { return __data_; }
+
+ // [span.iter], span iterator support
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() const noexcept {
+# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
+ return std::__make_bounded_iter(data(), data(), data() + size());
+# else
+ return iterator(data());
+# endif
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator end() const noexcept {
+# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
+ return std::__make_bounded_iter(data() + size(), data(), data() + size());
+# else
+ return iterator(data() + size());
+# endif
+ }
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI span<const byte, dynamic_extent> __as_bytes() const noexcept {
+ return {reinterpret_cast<const byte*>(data()), size_bytes()};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI span<byte, dynamic_extent> __as_writable_bytes() const noexcept {
+ return {reinterpret_cast<byte*>(data()), size_bytes()};
+ }
+
+private:
+ pointer __data_;
+ size_type __size_;
+};
+
+template <class _Tp, size_t _Extent>
+inline constexpr bool ranges::enable_borrowed_range<span<_Tp, _Extent> > = true;
+
+template <class _ElementType, size_t _Extent>
+inline constexpr bool ranges::enable_view<span<_ElementType, _Extent>> = true;
+
+// as_bytes & as_writable_bytes
+template <class _Tp, size_t _Extent>
+_LIBCPP_HIDE_FROM_ABI auto as_bytes(span<_Tp, _Extent> __s) noexcept {
+ return __s.__as_bytes();
+}
+
+template <class _Tp, size_t _Extent>
+ requires(!is_const_v<_Tp>)
+_LIBCPP_HIDE_FROM_ABI auto as_writable_bytes(span<_Tp, _Extent> __s) noexcept {
+ return __s.__as_writable_bytes();
+}
+
+# if _LIBCPP_STD_VER >= 26
+template <class _Tp>
+concept __integral_constant_like =
+ is_integral_v<decltype(_Tp::value)> && !is_same_v<bool, remove_const_t<decltype(_Tp::value)>> &&
+ convertible_to<_Tp, decltype(_Tp::value)> && equality_comparable_with<_Tp, decltype(_Tp::value)> &&
+ bool_constant<_Tp() == _Tp::value>::value &&
+ bool_constant<static_cast<decltype(_Tp::value)>(_Tp()) == _Tp::value>::value;
+
+template <class _Tp>
+inline constexpr size_t __maybe_static_ext = dynamic_extent;
+
+template <__integral_constant_like _Tp>
+inline constexpr size_t __maybe_static_ext<_Tp> = {_Tp::value};
+
+template <contiguous_iterator _It, class _EndOrSize>
+span(_It, _EndOrSize) -> span<remove_reference_t<iter_reference_t<_It>>, __maybe_static_ext<_EndOrSize>>;
+# else
+template <contiguous_iterator _It, class _EndOrSize>
+span(_It, _EndOrSize) -> span<remove_reference_t<iter_reference_t<_It>>>;
+# endif
+
+template <class _Tp, size_t _Sz>
+span(_Tp (&)[_Sz]) -> span<_Tp, _Sz>;
+
+template <class _Tp, size_t _Sz>
+span(array<_Tp, _Sz>&) -> span<_Tp, _Sz>;
+
+template <class _Tp, size_t _Sz>
+span(const array<_Tp, _Sz>&) -> span<const _Tp, _Sz>;
+
+template <ranges::contiguous_range _Range>
+span(_Range&&) -> span<remove_reference_t<ranges::range_reference_t<_Range>>>;
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <array>
+# include <concepts>
+# include <functional>
+# include <iterator>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_SPAN
diff --git a/libcxx/include/__cxx03/sstream b/libcxx/include/__cxx03/sstream
new file mode 100644
index 00000000000000..9ba43ffeb850f2
--- /dev/null
+++ b/libcxx/include/__cxx03/sstream
@@ -0,0 +1,1276 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SSTREAM
+#define _LIBCPP_SSTREAM
+
+// clang-format off
+
+/*
+ sstream synopsis [sstream.syn]
+
+// Class template basic_stringbuf [stringbuf]
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+class basic_stringbuf
+ : public basic_streambuf<charT, traits>
+{
+public:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef Allocator allocator_type;
+
+ // [stringbuf.cons] constructors:
+ explicit basic_stringbuf(ios_base::openmode which = ios_base::in | ios_base::out); // before C++20
+ basic_stringbuf() : basic_stringbuf(ios_base::in | ios_base::out) {} // C++20
+ explicit basic_stringbuf(ios_base::openmode which); // C++20
+ explicit basic_stringbuf(const basic_string<char_type, traits_type, allocator_type>& s,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ explicit basic_stringbuf(const allocator_type& a)
+ : basic_stringbuf(ios_base::in | ios_base::out, a) {} // C++20
+ basic_stringbuf(ios_base::openmode which, const allocator_type& a); // C++20
+ explicit basic_stringbuf(basic_string<char_type, traits_type, allocator_type>&& s,
+ ios_base::openmode which = ios_base::in | ios_base::out); // C++20
+ template <class SAlloc>
+ basic_stringbuf(const basic_string<char_type, traits_type, SAlloc>& s, const allocator_type& a)
+ : basic_stringbuf(s, ios_base::in | ios_base::out, a) {} // C++20
+ template <class SAlloc>
+ basic_stringbuf(const basic_string<char_type, traits_type, SAlloc>& s,
+ ios_base::openmode which, const allocator_type& a); // C++20
+ template <class SAlloc>
+ explicit basic_stringbuf(const basic_string<char_type, traits_type, SAlloc>& s,
+ ios_base::openmode which = ios_base::in | ios_base::out); // C++20
+ template<class T>
+ explicit basic_stringbuf(const T& t,
+ ios_base::openmode which = ios_base::in | ios_base::out); // Since C++26
+ template<class T>
+ basic_stringbuf(const T& t, const Allocator& a); // Since C++26
+ template<class T>
+ basic_stringbuf(const T& t, ios_base::openmode which, const Allocator& a); // Since C++26
+ basic_stringbuf(const basic_stringbuf&) = delete;
+ basic_stringbuf(basic_stringbuf&& rhs);
+ basic_stringbuf(basic_stringbuf&& rhs, const allocator_type& a); // C++20
+
+ // [stringbuf.assign] Assign and swap:
+ basic_stringbuf& operator=(const basic_stringbuf&) = delete;
+ basic_stringbuf& operator=(basic_stringbuf&& rhs);
+ void swap(basic_stringbuf& rhs) noexcept(see below); // conditionally noexcept since C++20
+
+ // [stringbuf.members] Member functions:
+ allocator_type get_allocator() const noexcept; // C++20
+ basic_string<char_type, traits_type, allocator_type> str() const; // before C++20
+ basic_string<char_type, traits_type, allocator_type> str() const &; // C++20
+ template <class SAlloc>
+ basic_string<char_type, traits_type, SAlloc> str(const SAlloc& sa) const; // C++20
+ basic_string<char_type, traits_type, allocator_type> str() &&; // C++20
+ basic_string_view<char_type, traits_type> view() const noexcept; // C++20
+ void str(const basic_string<char_type, traits_type, allocator_type>& s);
+ template <class SAlloc>
+ void str(const basic_string<char_type, traits_type, SAlloc>& s); // C++20
+ void str(basic_string<char_type, traits_type, allocator_type>&& s); // C++20
+ template<class T>
+ void str(const T& t); // Since C++26
+
+protected:
+ // [stringbuf.virtuals] Overridden virtual functions:
+ virtual int_type underflow();
+ virtual int_type pbackfail(int_type c = traits_type::eof());
+ virtual int_type overflow (int_type c = traits_type::eof());
+ virtual basic_streambuf<char_type, traits_type>* setbuf(char_type*, streamsize);
+ virtual pos_type seekoff(off_type off, ios_base::seekdir way,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ virtual pos_type seekpos(pos_type sp,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+};
+
+// [stringbuf.assign] non member swap
+template <class charT, class traits, class Allocator>
+void swap(basic_stringbuf<charT, traits, Allocator>& x,
+ basic_stringbuf<charT, traits, Allocator>& y); // conditionally noexcept since C++20
+
+typedef basic_stringbuf<char> stringbuf;
+typedef basic_stringbuf<wchar_t> wstringbuf;
+
+// Class template basic_istringstream [istringstream]
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+class basic_istringstream
+ : public basic_istream<charT, traits>
+{
+public:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef Allocator allocator_type;
+
+ // [istringstream.cons] Constructors:
+ explicit basic_istringstream(ios_base::openmode which = ios_base::in); // before C++20
+ basic_istringstream() : basic_istringstream(ios_base::in) {} // C++20
+ explicit basic_istringstream(ios_base::openmode which); // C++20
+ explicit basic_istringstream(const basic_string<char_type, traits_type, allocator_type>& s,
+ ios_base::openmode which = ios_base::in);
+ basic_istringstream(ios_base::openmode which, const allocator_type& a); // C++20
+ explicit basic_istringstream(basic_string<char_type, traits_type, allocator_type>&& s,
+ ios_base::openmode which = ios_base::in); // C++20
+ template <class SAlloc>
+ basic_istringstream(const basic_string<char_type, traits_type, SAlloc>& s, const allocator_type& a)
+ : basic_istringstream(s, ios_base::in, a) {} // C++20
+ template <class SAlloc>
+ basic_istringstream(const basic_string<char_type, traits_type, SAlloc>& s,
+ ios_base::openmode which, const allocator_type& a); // C++20
+ template <class SAlloc>
+ explicit basic_istringstream(const basic_string<char_type, traits_type, SAlloc>& s,
+ ios_base::openmode which = ios_base::in); // C++20
+ template<class T>
+ explicit basic_istringstream(const T& t, ios_base::openmode which = ios_base::in); // Since C++26
+ template<class T>
+ basic_istringstream(const T& t, const Allocator& a); // Since C++26
+ template<class T>
+ basic_istringstream(const T& t, ios_base::openmode which, const Allocator& a); // Since C++26
+ basic_istringstream(const basic_istringstream&) = delete;
+ basic_istringstream(basic_istringstream&& rhs);
+
+ // [istringstream.assign] Assign and swap:
+ basic_istringstream& operator=(const basic_istringstream&) = delete;
+ basic_istringstream& operator=(basic_istringstream&& rhs);
+ void swap(basic_istringstream& rhs);
+
+ // [istringstream.members] Member functions:
+ basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
+ basic_string<char_type, traits_type, allocator_type> str() const; // before C++20
+ basic_string<char_type, traits_type, allocator_type> str() const &; // C++20
+ template <class SAlloc>
+ basic_string<char_type, traits_type, SAlloc> str(const SAlloc& sa) const; // C++20
+ basic_string<char_type, traits_type, allocator_type> str() &&; // C++20
+ basic_string_view<char_type, traits_type> view() const noexcept; // C++20
+ void str(const basic_string<char_type, traits_type, allocator_type>& s);
+ template <class SAlloc>
+ void str(const basic_string<char_type, traits_type, SAlloc>& s); // C++20
+ void str(basic_string<char_type, traits_type, allocator_type>&& s); // C++20
+ template<class T>
+ void str(const T& t); // Since C++26
+};
+
+template <class charT, class traits, class Allocator>
+void swap(basic_istringstream<charT, traits, Allocator>& x,
+ basic_istringstream<charT, traits, Allocator>& y);
+
+typedef basic_istringstream<char> istringstream;
+typedef basic_istringstream<wchar_t> wistringstream;
+
+// Class template basic_ostringstream [ostringstream]
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+class basic_ostringstream
+ : public basic_ostream<charT, traits>
+{
+public:
+ // types:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef Allocator allocator_type;
+
+ // [ostringstream.cons] Constructors:
+ explicit basic_ostringstream(ios_base::openmode which = ios_base::out); // before C++20
+ basic_ostringstream() : basic_ostringstream(ios_base::out) {} // C++20
+ explicit basic_ostringstream(ios_base::openmode which); // C++20
+ explicit basic_ostringstream(const basic_string<char_type, traits_type, allocator_type>& s,
+ ios_base::openmode which = ios_base::out);
+ basic_ostringstream(ios_base::openmode which, const allocator_type& a); // C++20
+ explicit basic_ostringstream(basic_string<char_type, traits_type, allocator_type>&& s,
+ ios_base::openmode which = ios_base::out); // C++20
+ template <class SAlloc>
+ basic_ostringstream(const basic_string<char_type, traits_type, SAlloc>& s, const allocator_type& a)
+ : basic_ostringstream(s, ios_base::out, a) {} // C++20
+ template <class SAlloc>
+ basic_ostringstream(const basic_string<char_type, traits_type, SAlloc>& s,
+ ios_base::openmode which, const allocator_type& a); // C++20
+ template <class SAlloc>
+ explicit basic_ostringstream(const basic_string<char_type, traits_type, SAlloc>& s,
+ ios_base::openmode which = ios_base::out); // C++20
+ template<class T>
+ explicit basic_ostringstream(const T& t, ios_base::openmode which = ios_base::out); // Since C++26
+ template<class T>
+ basic_ostringstream(const T& t, const Allocator& a); // Since C++26
+ template<class T>
+ basic_ostringstream(const T& t, ios_base::openmode which, const Allocator& a); // Since C++26
+ basic_ostringstream(const basic_ostringstream&) = delete;
+ basic_ostringstream(basic_ostringstream&& rhs);
+
+ // [ostringstream.assign] Assign and swap:
+ basic_ostringstream& operator=(const basic_ostringstream&) = delete;
+ basic_ostringstream& operator=(basic_ostringstream&& rhs);
+ void swap(basic_ostringstream& rhs);
+
+ // [ostringstream.members] Member functions:
+ basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
+ basic_string<char_type, traits_type, allocator_type> str() const; // before C++20
+ basic_string<char_type, traits_type, allocator_type> str() const &; // C++20
+ template <class SAlloc>
+ basic_string<char_type, traits_type, SAlloc> str(const SAlloc& sa) const; // C++20
+ basic_string<char_type, traits_type, allocator_type> str() &&; // C++20
+ basic_string_view<char_type, traits_type> view() const noexcept; // C++20
+ void str(const basic_string<char_type, traits_type, allocator_type>& s);
+ template <class SAlloc>
+ void str(const basic_string<char_type, traits_type, SAlloc>& s); // C++20
+ void str(basic_string<char_type, traits_type, allocator_type>&& s); // C++20
+ template<class T>
+ void str(const T& t); // Since C++26
+};
+
+template <class charT, class traits, class Allocator>
+void swap(basic_ostringstream<charT, traits, Allocator>& x,
+ basic_ostringstream<charT, traits, Allocator>& y);
+
+typedef basic_ostringstream<char> ostringstream;
+typedef basic_ostringstream<wchar_t> wostringstream;
+
+// Class template basic_stringstream [stringstream]
+template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+class basic_stringstream
+ : public basic_iostream<charT, traits>
+{
+public:
+ // types:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef Allocator allocator_type;
+
+ // [stringstream.cons] constructors
+ explicit basic_stringstream(ios_base::openmode which = ios_base::out | ios_base::in); // before C++20
+ basic_stringstream() : basic_stringstream(ios_base::out | ios_base::in) {} // C++20
+ explicit basic_stringstream(ios_base::openmode which); // C++20
+ explicit basic_stringstream(const basic_string<char_type, traits_type, allocator_type>& s,
+ ios_base::openmode which = ios_base::out | ios_base::in);
+ basic_stringstream(ios_base::openmode which, const allocator_type& a); // C++20
+ explicit basic_stringstream(basic_string<char_type, traits_type, allocator_type>&& s,
+ ios_base::openmode which = ios_base::out | ios_base::in); // C++20
+ template <class SAlloc>
+ basic_stringstream(const basic_string<char_type, traits_type, SAlloc>& s, const allocator_type& a)
+ : basic_stringstream(s, ios_base::out | ios_base::in, a) {} // C++20
+ template <class SAlloc>
+ basic_stringstream(const basic_string<char_type, traits_type, SAlloc>& s,
+ ios_base::openmode which, const allocator_type& a); // C++20
+ template <class SAlloc>
+ explicit basic_stringstream(const basic_string<char_type, traits_type, SAlloc>& s,
+ ios_base::openmode which = ios_base::out | ios_base::in); // C++20
+ template<class T>
+ explicit basic_stringstream(const T& t,
+ ios_base::openmode which = ios_base::out | ios_base::in); // Since C++26
+ template<class T>
+ basic_stringstream(const T& t, const Allocator& a); // Since C++26
+ template<class T>
+ basic_stringstream(const T& t, ios_base::openmode which, const Allocator& a); // Since C++26
+ basic_stringstream(const basic_stringstream&) = delete;
+ basic_stringstream(basic_stringstream&& rhs);
+
+ // [stringstream.assign] Assign and swap:
+ basic_stringstream& operator=(const basic_stringstream&) = delete;
+ basic_stringstream& operator=(basic_stringstream&& rhs);
+ void swap(basic_stringstream& rhs);
+
+ // [stringstream.members] Member functions:
+ basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
+ basic_string<char_type, traits_type, allocator_type> str() const; // before C++20
+ basic_string<char_type, traits_type, allocator_type> str() const &; // C++20
+ template <class SAlloc>
+ basic_string<char_type, traits_type, SAlloc> str(const SAlloc& sa) const; // C++20
+ basic_string<char_type, traits_type, allocator_type> str() &&; // C++20
+ basic_string_view<char_type, traits_type> view() const noexcept; // C++20
+ void str(const basic_string<char_type, traits_type, allocator_type>& s);
+ template <class SAlloc>
+ void str(const basic_string<char_type, traits_type, SAlloc>& s); // C++20
+ void str(basic_string<char_type, traits_type, allocator_type>&& s); // C++20
+ template<class T>
+ void str(const T& t); // Since C++26
+};
+
+template <class charT, class traits, class Allocator>
+void swap(basic_stringstream<charT, traits, Allocator>& x,
+ basic_stringstream<charT, traits, Allocator>& y);
+
+typedef basic_stringstream<char> stringstream;
+typedef basic_stringstream<wchar_t> wstringstream;
+
+} // std
+
+*/
+
+// clang-format on
+
+#include <__config>
+#include <__fwd/sstream.h>
+#include <__ostream/basic_ostream.h>
+#include <__type_traits/is_convertible.h>
+#include <__utility/swap.h>
+#include <istream>
+#include <string>
+#include <string_view>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// Class template basic_stringbuf [stringbuf]
+
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_TEMPLATE_VIS basic_stringbuf : public basic_streambuf<_CharT, _Traits> {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef _Allocator allocator_type;
+
+ typedef basic_string<char_type, traits_type, allocator_type> string_type;
+
+private:
+ string_type __str_;
+ mutable char_type* __hm_;
+ ios_base::openmode __mode_;
+ _LIBCPP_HIDE_FROM_ABI void __init_buf_ptrs();
+ _LIBCPP_HIDE_FROM_ABI void __move_init(basic_stringbuf&& __rhs);
+
+public:
+ // [stringbuf.cons] constructors:
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf() : __hm_(nullptr), __mode_(ios_base::in | ios_base::out) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringbuf(ios_base::openmode __wch) : __hm_(nullptr), __mode_(__wch) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringbuf(const string_type& __s,
+ ios_base::openmode __wch = ios_base::in | ios_base::out)
+ : __str_(__s.get_allocator()), __hm_(nullptr), __mode_(__wch) {
+ str(__s);
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringbuf(const allocator_type& __a)
+ : basic_stringbuf(ios_base::in | ios_base::out, __a) {}
+
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf(ios_base::openmode __wch, const allocator_type& __a)
+ : __str_(__a), __hm_(nullptr), __mode_(__wch) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringbuf(string_type&& __s,
+ ios_base::openmode __wch = ios_base::in | ios_base::out)
+ : __str_(std::move(__s)), __hm_(nullptr), __mode_(__wch) {
+ __init_buf_ptrs();
+ }
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI
+ basic_stringbuf(const basic_string<char_type, traits_type, _SAlloc>& __s, const allocator_type& __a)
+ : basic_stringbuf(__s, ios_base::in | ios_base::out, __a) {}
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf(
+ const basic_string<char_type, traits_type, _SAlloc>& __s, ios_base::openmode __wch, const allocator_type& __a)
+ : __str_(__s, __a), __hm_(nullptr), __mode_(__wch) {
+ __init_buf_ptrs();
+ }
+
+ template <class _SAlloc>
+ requires(!is_same_v<_SAlloc, allocator_type>)
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringbuf(const basic_string<char_type, traits_type, _SAlloc>& __s,
+ ios_base::openmode __wch = ios_base::in | ios_base::out)
+ : __str_(__s), __hm_(nullptr), __mode_(__wch) {
+ __init_buf_ptrs();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringbuf(const _Tp& __t,
+ ios_base::openmode __which = ios_base::in | ios_base::out)
+ : basic_stringbuf(__t, __which, _Allocator()) {}
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf(const _Tp& __t, const _Allocator& __a)
+ : basic_stringbuf(__t, ios_base::in | ios_base::out, __a) {}
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf(const _Tp& __t, ios_base::openmode __which, const _Allocator& __a)
+ : __hm_(nullptr), __mode_(__which) {
+ basic_string_view<_CharT, _Traits> __sv = __t;
+ __str_ = string_type(__sv, __a);
+ __init_buf_ptrs();
+ }
+
+#endif // _LIBCPP_STD_VER >= 26
+
+ basic_stringbuf(const basic_stringbuf&) = delete;
+ basic_stringbuf(basic_stringbuf&& __rhs) : __mode_(__rhs.__mode_) { __move_init(std::move(__rhs)); }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf(basic_stringbuf&& __rhs, const allocator_type& __a)
+ : basic_stringbuf(__rhs.__mode_, __a) {
+ __move_init(std::move(__rhs));
+ }
+#endif
+
+ // [stringbuf.assign] Assign and swap:
+ basic_stringbuf& operator=(const basic_stringbuf&) = delete;
+ basic_stringbuf& operator=(basic_stringbuf&& __rhs);
+ void swap(basic_stringbuf& __rhs)
+#if _LIBCPP_STD_VER >= 20
+ noexcept(allocator_traits<allocator_type>::propagate_on_container_swap::value ||
+ allocator_traits<allocator_type>::is_always_equal::value)
+#endif
+ ;
+
+ // [stringbuf.members] Member functions:
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const noexcept { return __str_.get_allocator(); }
+#endif
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_BUILDING_LIBRARY)
+ string_type str() const;
+#else
+ _LIBCPP_HIDE_FROM_ABI string_type str() const& { return str(__str_.get_allocator()); }
+
+ _LIBCPP_HIDE_FROM_ABI string_type str() && {
+ const basic_string_view<_CharT, _Traits> __view = view();
+ typename string_type::size_type __pos = __view.empty() ? 0 : __view.data() - __str_.data();
+ // In C++23, this is just string_type(std::move(__str_), __pos, __view.size(), __str_.get_allocator());
+ // But we need something that works in C++20 also.
+ string_type __result(std::move(__str_), __str_.get_allocator());
+ __result.resize(__pos + __view.size());
+ __result.erase(0, __pos);
+ __init_buf_ptrs();
+ return __result;
+ }
+#endif // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_BUILDING_LIBRARY)
+
+#if _LIBCPP_STD_VER >= 20
+ template <class _SAlloc>
+ requires __is_allocator<_SAlloc>::value
+ _LIBCPP_HIDE_FROM_ABI basic_string<char_type, traits_type, _SAlloc> str(const _SAlloc& __sa) const {
+ return basic_string<_CharT, _Traits, _SAlloc>(view(), __sa);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_string_view<char_type, traits_type> view() const noexcept;
+#endif // _LIBCPP_STD_VER >= 20
+
+ void str(const string_type& __s) {
+ __str_ = __s;
+ __init_buf_ptrs();
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ template <class _SAlloc>
+ requires(!is_same_v<_SAlloc, allocator_type>)
+ _LIBCPP_HIDE_FROM_ABI void str(const basic_string<char_type, traits_type, _SAlloc>& __s) {
+ __str_ = __s;
+ __init_buf_ptrs();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void str(string_type&& __s) {
+ __str_ = std::move(__s);
+ __init_buf_ptrs();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI void str(const _Tp& __t) {
+ basic_string_view<_CharT, _Traits> __sv = __t;
+ __str_ = __sv;
+ __init_buf_ptrs();
+ }
+
+#endif // _LIBCPP_STD_VER >= 26
+
+protected:
+ // [stringbuf.virtuals] Overridden virtual functions:
+ int_type underflow() override;
+ int_type pbackfail(int_type __c = traits_type::eof()) override;
+ int_type overflow(int_type __c = traits_type::eof()) override;
+ pos_type
+ seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __wch = ios_base::in | ios_base::out) override;
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ pos_type seekpos(pos_type __sp, ios_base::openmode __wch = ios_base::in | ios_base::out) override {
+ return seekoff(__sp, ios_base::beg, __wch);
+ }
+};
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI void basic_stringbuf<_CharT, _Traits, _Allocator>::__move_init(basic_stringbuf&& __rhs) {
+ char_type* __p = const_cast<char_type*>(__rhs.__str_.data());
+ ptrdiff_t __binp = -1;
+ ptrdiff_t __ninp = -1;
+ ptrdiff_t __einp = -1;
+ if (__rhs.eback() != nullptr) {
+ __binp = __rhs.eback() - __p;
+ __ninp = __rhs.gptr() - __p;
+ __einp = __rhs.egptr() - __p;
+ }
+ ptrdiff_t __bout = -1;
+ ptrdiff_t __nout = -1;
+ ptrdiff_t __eout = -1;
+ if (__rhs.pbase() != nullptr) {
+ __bout = __rhs.pbase() - __p;
+ __nout = __rhs.pptr() - __p;
+ __eout = __rhs.epptr() - __p;
+ }
+ ptrdiff_t __hm = __rhs.__hm_ == nullptr ? -1 : __rhs.__hm_ - __p;
+ __str_ = std::move(__rhs.__str_);
+ __p = const_cast<char_type*>(__str_.data());
+ if (__binp != -1)
+ this->setg(__p + __binp, __p + __ninp, __p + __einp);
+ if (__bout != -1) {
+ this->setp(__p + __bout, __p + __eout);
+ this->__pbump(__nout);
+ }
+ __hm_ = __hm == -1 ? nullptr : __p + __hm;
+ __p = const_cast<char_type*>(__rhs.__str_.data());
+ __rhs.setg(__p, __p, __p);
+ __rhs.setp(__p, __p);
+ __rhs.__hm_ = __p;
+ this->pubimbue(__rhs.getloc());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+basic_stringbuf<_CharT, _Traits, _Allocator>&
+basic_stringbuf<_CharT, _Traits, _Allocator>::operator=(basic_stringbuf&& __rhs) {
+ char_type* __p = const_cast<char_type*>(__rhs.__str_.data());
+ ptrdiff_t __binp = -1;
+ ptrdiff_t __ninp = -1;
+ ptrdiff_t __einp = -1;
+ if (__rhs.eback() != nullptr) {
+ __binp = __rhs.eback() - __p;
+ __ninp = __rhs.gptr() - __p;
+ __einp = __rhs.egptr() - __p;
+ }
+ ptrdiff_t __bout = -1;
+ ptrdiff_t __nout = -1;
+ ptrdiff_t __eout = -1;
+ if (__rhs.pbase() != nullptr) {
+ __bout = __rhs.pbase() - __p;
+ __nout = __rhs.pptr() - __p;
+ __eout = __rhs.epptr() - __p;
+ }
+ ptrdiff_t __hm = __rhs.__hm_ == nullptr ? -1 : __rhs.__hm_ - __p;
+ __str_ = std::move(__rhs.__str_);
+ __p = const_cast<char_type*>(__str_.data());
+ if (__binp != -1)
+ this->setg(__p + __binp, __p + __ninp, __p + __einp);
+ else
+ this->setg(nullptr, nullptr, nullptr);
+ if (__bout != -1) {
+ this->setp(__p + __bout, __p + __eout);
+ this->__pbump(__nout);
+ } else
+ this->setp(nullptr, nullptr);
+
+ __hm_ = __hm == -1 ? nullptr : __p + __hm;
+ __mode_ = __rhs.__mode_;
+ __p = const_cast<char_type*>(__rhs.__str_.data());
+ __rhs.setg(__p, __p, __p);
+ __rhs.setp(__p, __p);
+ __rhs.__hm_ = __p;
+ this->pubimbue(__rhs.getloc());
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+void basic_stringbuf<_CharT, _Traits, _Allocator>::swap(basic_stringbuf& __rhs)
+#if _LIBCPP_STD_VER >= 20
+ noexcept(allocator_traits<_Allocator>::propagate_on_container_swap::value ||
+ allocator_traits<_Allocator>::is_always_equal::value)
+#endif
+{
+ char_type* __p = const_cast<char_type*>(__rhs.__str_.data());
+ ptrdiff_t __rbinp = -1;
+ ptrdiff_t __rninp = -1;
+ ptrdiff_t __reinp = -1;
+ if (__rhs.eback() != nullptr) {
+ __rbinp = __rhs.eback() - __p;
+ __rninp = __rhs.gptr() - __p;
+ __reinp = __rhs.egptr() - __p;
+ }
+ ptrdiff_t __rbout = -1;
+ ptrdiff_t __rnout = -1;
+ ptrdiff_t __reout = -1;
+ if (__rhs.pbase() != nullptr) {
+ __rbout = __rhs.pbase() - __p;
+ __rnout = __rhs.pptr() - __p;
+ __reout = __rhs.epptr() - __p;
+ }
+ ptrdiff_t __rhm = __rhs.__hm_ == nullptr ? -1 : __rhs.__hm_ - __p;
+ __p = const_cast<char_type*>(__str_.data());
+ ptrdiff_t __lbinp = -1;
+ ptrdiff_t __lninp = -1;
+ ptrdiff_t __leinp = -1;
+ if (this->eback() != nullptr) {
+ __lbinp = this->eback() - __p;
+ __lninp = this->gptr() - __p;
+ __leinp = this->egptr() - __p;
+ }
+ ptrdiff_t __lbout = -1;
+ ptrdiff_t __lnout = -1;
+ ptrdiff_t __leout = -1;
+ if (this->pbase() != nullptr) {
+ __lbout = this->pbase() - __p;
+ __lnout = this->pptr() - __p;
+ __leout = this->epptr() - __p;
+ }
+ ptrdiff_t __lhm = __hm_ == nullptr ? -1 : __hm_ - __p;
+ std::swap(__mode_, __rhs.__mode_);
+ __str_.swap(__rhs.__str_);
+ __p = const_cast<char_type*>(__str_.data());
+ if (__rbinp != -1)
+ this->setg(__p + __rbinp, __p + __rninp, __p + __reinp);
+ else
+ this->setg(nullptr, nullptr, nullptr);
+ if (__rbout != -1) {
+ this->setp(__p + __rbout, __p + __reout);
+ this->__pbump(__rnout);
+ } else
+ this->setp(nullptr, nullptr);
+ __hm_ = __rhm == -1 ? nullptr : __p + __rhm;
+ __p = const_cast<char_type*>(__rhs.__str_.data());
+ if (__lbinp != -1)
+ __rhs.setg(__p + __lbinp, __p + __lninp, __p + __leinp);
+ else
+ __rhs.setg(nullptr, nullptr, nullptr);
+ if (__lbout != -1) {
+ __rhs.setp(__p + __lbout, __p + __leout);
+ __rhs.__pbump(__lnout);
+ } else
+ __rhs.setp(nullptr, nullptr);
+ __rhs.__hm_ = __lhm == -1 ? nullptr : __p + __lhm;
+ locale __tl = __rhs.getloc();
+ __rhs.pubimbue(this->getloc());
+ this->pubimbue(__tl);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(basic_stringbuf<_CharT, _Traits, _Allocator>& __x, basic_stringbuf<_CharT, _Traits, _Allocator>& __y)
+#if _LIBCPP_STD_VER >= 20
+ noexcept(noexcept(__x.swap(__y)))
+#endif
+{
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_BUILDING_LIBRARY)
+template <class _CharT, class _Traits, class _Allocator>
+basic_string<_CharT, _Traits, _Allocator> basic_stringbuf<_CharT, _Traits, _Allocator>::str() const {
+ if (__mode_ & ios_base::out) {
+ if (__hm_ < this->pptr())
+ __hm_ = this->pptr();
+ return string_type(this->pbase(), __hm_, __str_.get_allocator());
+ } else if (__mode_ & ios_base::in)
+ return string_type(this->eback(), this->egptr(), __str_.get_allocator());
+ return string_type(__str_.get_allocator());
+}
+#endif // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_BUILDING_LIBRARY)
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI void basic_stringbuf<_CharT, _Traits, _Allocator>::__init_buf_ptrs() {
+ __hm_ = nullptr;
+ char_type* __data = const_cast<char_type*>(__str_.data());
+ typename string_type::size_type __sz = __str_.size();
+ if (__mode_ & ios_base::in) {
+ __hm_ = __data + __sz;
+ this->setg(__data, __data, __hm_);
+ }
+ if (__mode_ & ios_base::out) {
+ __hm_ = __data + __sz;
+ __str_.resize(__str_.capacity());
+ this->setp(__data, __data + __str_.size());
+ if (__mode_ & (ios_base::app | ios_base::ate)) {
+ while (__sz > INT_MAX) {
+ this->pbump(INT_MAX);
+ __sz -= INT_MAX;
+ }
+ if (__sz > 0)
+ this->pbump(__sz);
+ }
+ }
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI basic_string_view<_CharT, _Traits>
+basic_stringbuf<_CharT, _Traits, _Allocator>::view() const noexcept {
+ if (__mode_ & ios_base::out) {
+ if (__hm_ < this->pptr())
+ __hm_ = this->pptr();
+ return basic_string_view<_CharT, _Traits>(this->pbase(), __hm_);
+ } else if (__mode_ & ios_base::in)
+ return basic_string_view<_CharT, _Traits>(this->eback(), this->egptr());
+ return basic_string_view<_CharT, _Traits>();
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _CharT, class _Traits, class _Allocator>
+typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
+basic_stringbuf<_CharT, _Traits, _Allocator>::underflow() {
+ if (__hm_ < this->pptr())
+ __hm_ = this->pptr();
+ if (__mode_ & ios_base::in) {
+ if (this->egptr() < __hm_)
+ this->setg(this->eback(), this->gptr(), __hm_);
+ if (this->gptr() < this->egptr())
+ return traits_type::to_int_type(*this->gptr());
+ }
+ return traits_type::eof();
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
+basic_stringbuf<_CharT, _Traits, _Allocator>::pbackfail(int_type __c) {
+ if (__hm_ < this->pptr())
+ __hm_ = this->pptr();
+ if (this->eback() < this->gptr()) {
+ if (traits_type::eq_int_type(__c, traits_type::eof())) {
+ this->setg(this->eback(), this->gptr() - 1, __hm_);
+ return traits_type::not_eof(__c);
+ }
+ if ((__mode_ & ios_base::out) || traits_type::eq(traits_type::to_char_type(__c), this->gptr()[-1])) {
+ this->setg(this->eback(), this->gptr() - 1, __hm_);
+ *this->gptr() = traits_type::to_char_type(__c);
+ return __c;
+ }
+ }
+ return traits_type::eof();
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
+basic_stringbuf<_CharT, _Traits, _Allocator>::overflow(int_type __c) {
+ if (!traits_type::eq_int_type(__c, traits_type::eof())) {
+ ptrdiff_t __ninp = this->gptr() - this->eback();
+ if (this->pptr() == this->epptr()) {
+ if (!(__mode_ & ios_base::out))
+ return traits_type::eof();
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ ptrdiff_t __nout = this->pptr() - this->pbase();
+ ptrdiff_t __hm = __hm_ - this->pbase();
+ __str_.push_back(char_type());
+ __str_.resize(__str_.capacity());
+ char_type* __p = const_cast<char_type*>(__str_.data());
+ this->setp(__p, __p + __str_.size());
+ this->__pbump(__nout);
+ __hm_ = this->pbase() + __hm;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ return traits_type::eof();
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+ __hm_ = std::max(this->pptr() + 1, __hm_);
+ if (__mode_ & ios_base::in) {
+ char_type* __p = const_cast<char_type*>(__str_.data());
+ this->setg(__p, __p + __ninp, __hm_);
+ }
+ return this->sputc(traits_type::to_char_type(__c));
+ }
+ return traits_type::not_eof(__c);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+typename basic_stringbuf<_CharT, _Traits, _Allocator>::pos_type basic_stringbuf<_CharT, _Traits, _Allocator>::seekoff(
+ off_type __off, ios_base::seekdir __way, ios_base::openmode __wch) {
+ if (__hm_ < this->pptr())
+ __hm_ = this->pptr();
+ if ((__wch & (ios_base::in | ios_base::out)) == 0)
+ return pos_type(-1);
+ if ((__wch & (ios_base::in | ios_base::out)) == (ios_base::in | ios_base::out) && __way == ios_base::cur)
+ return pos_type(-1);
+ const ptrdiff_t __hm = __hm_ == nullptr ? 0 : __hm_ - __str_.data();
+ off_type __noff;
+ switch (__way) {
+ case ios_base::beg:
+ __noff = 0;
+ break;
+ case ios_base::cur:
+ if (__wch & ios_base::in)
+ __noff = this->gptr() - this->eback();
+ else
+ __noff = this->pptr() - this->pbase();
+ break;
+ case ios_base::end:
+ __noff = __hm;
+ break;
+ default:
+ return pos_type(-1);
+ }
+ __noff += __off;
+ if (__noff < 0 || __hm < __noff)
+ return pos_type(-1);
+ if (__noff != 0) {
+ if ((__wch & ios_base::in) && this->gptr() == nullptr)
+ return pos_type(-1);
+ if ((__wch & ios_base::out) && this->pptr() == nullptr)
+ return pos_type(-1);
+ }
+ if (__wch & ios_base::in)
+ this->setg(this->eback(), this->eback() + __noff, __hm_);
+ if (__wch & ios_base::out) {
+ this->setp(this->pbase(), this->epptr());
+ this->__pbump(__noff);
+ }
+ return pos_type(__noff);
+}
+
+// Class template basic_istringstream [istringstream]
+
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_TEMPLATE_VIS basic_istringstream : public basic_istream<_CharT, _Traits> {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef _Allocator allocator_type;
+
+ typedef basic_string<char_type, traits_type, allocator_type> string_type;
+
+private:
+ basic_stringbuf<char_type, traits_type, allocator_type> __sb_;
+
+public:
+ // [istringstream.cons] Constructors:
+ _LIBCPP_HIDE_FROM_ABI basic_istringstream() : basic_istream<_CharT, _Traits>(&__sb_), __sb_(ios_base::in) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_istringstream(ios_base::openmode __wch)
+ : basic_istream<_CharT, _Traits>(&__sb_), __sb_(__wch | ios_base::in) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_istringstream(const string_type& __s, ios_base::openmode __wch = ios_base::in)
+ : basic_istream<_CharT, _Traits>(&__sb_), __sb_(__s, __wch | ios_base::in) {}
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI basic_istringstream(ios_base::openmode __wch, const _Allocator& __a)
+ : basic_istream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__wch | ios_base::in, __a) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_istringstream(string_type&& __s, ios_base::openmode __wch = ios_base::in)
+ : basic_istream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(std::move(__s), __wch | ios_base::in) {}
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI basic_istringstream(const basic_string<_CharT, _Traits, _SAlloc>& __s, const _Allocator& __a)
+ : basic_istringstream(__s, ios_base::in, __a) {}
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI basic_istringstream(
+ const basic_string<_CharT, _Traits, _SAlloc>& __s, ios_base::openmode __wch, const _Allocator& __a)
+ : basic_istream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__s, __wch | ios_base::in, __a) {}
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI explicit basic_istringstream(const basic_string<_CharT, _Traits, _SAlloc>& __s,
+ ios_base::openmode __wch = ios_base::in)
+ : basic_istream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__s, __wch | ios_base::in) {}
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI explicit basic_istringstream(const _Tp& __t, ios_base::openmode __which = ios_base::in)
+ : basic_istringstream(__t, __which, _Allocator()) {}
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI basic_istringstream(const _Tp& __t, const _Allocator& __a)
+ : basic_istringstream(__t, ios_base::in, __a) {}
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI basic_istringstream(const _Tp& __t, ios_base::openmode __which, const _Allocator& __a)
+ : basic_istream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__t, __which | ios_base::in, __a) {}
+
+#endif // _LIBCPP_STD_VER >= 26
+
+ basic_istringstream(const basic_istringstream&) = delete;
+ _LIBCPP_HIDE_FROM_ABI basic_istringstream(basic_istringstream&& __rhs)
+ : basic_istream<_CharT, _Traits>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
+ basic_istream<_CharT, _Traits>::set_rdbuf(&__sb_);
+ }
+
+ // [istringstream.assign] Assign and swap:
+ basic_istringstream& operator=(const basic_istringstream&) = delete;
+ basic_istringstream& operator=(basic_istringstream&& __rhs) {
+ basic_istream<char_type, traits_type>::operator=(std::move(__rhs));
+ __sb_ = std::move(__rhs.__sb_);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI void swap(basic_istringstream& __rhs) {
+ basic_istream<char_type, traits_type>::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+ }
+
+ // [istringstream.members] Member functions:
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const {
+ return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
+ }
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_BUILDING_LIBRARY)
+ _LIBCPP_HIDE_FROM_ABI string_type str() const { return __sb_.str(); }
+#else
+ _LIBCPP_HIDE_FROM_ABI string_type str() const& { return __sb_.str(); }
+
+ _LIBCPP_HIDE_FROM_ABI string_type str() && { return std::move(__sb_).str(); }
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+ template <class _SAlloc>
+ requires __is_allocator<_SAlloc>::value
+ _LIBCPP_HIDE_FROM_ABI basic_string<char_type, traits_type, _SAlloc> str(const _SAlloc& __sa) const {
+ return __sb_.str(__sa);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_string_view<char_type, traits_type> view() const noexcept { return __sb_.view(); }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI void str(const string_type& __s) { __sb_.str(__s); }
+
+#if _LIBCPP_STD_VER >= 20
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI void str(const basic_string<char_type, traits_type, _SAlloc>& __s) {
+ __sb_.str(__s);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void str(string_type&& __s) { __sb_.str(std::move(__s)); }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI void str(const _Tp& __t) {
+ rdbuf()->str(__t);
+ }
+#endif // _LIBCPP_STD_VER >= 26
+};
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(basic_istringstream<_CharT, _Traits, _Allocator>& __x, basic_istringstream<_CharT, _Traits, _Allocator>& __y) {
+ __x.swap(__y);
+}
+
+// Class template basic_ostringstream [ostringstream]
+
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_TEMPLATE_VIS basic_ostringstream : public basic_ostream<_CharT, _Traits> {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef _Allocator allocator_type;
+
+ typedef basic_string<char_type, traits_type, allocator_type> string_type;
+
+private:
+ basic_stringbuf<char_type, traits_type, allocator_type> __sb_;
+
+public:
+ // [ostringstream.cons] Constructors:
+ _LIBCPP_HIDE_FROM_ABI basic_ostringstream() : basic_ostream<_CharT, _Traits>(&__sb_), __sb_(ios_base::out) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ostringstream(ios_base::openmode __wch)
+ : basic_ostream<_CharT, _Traits>(&__sb_), __sb_(__wch | ios_base::out) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ostringstream(const string_type& __s, ios_base::openmode __wch = ios_base::out)
+ : basic_ostream<_CharT, _Traits>(&__sb_), __sb_(__s, __wch | ios_base::out) {}
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI basic_ostringstream(ios_base::openmode __wch, const _Allocator& __a)
+ : basic_ostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__wch | ios_base::out, __a) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ostringstream(string_type&& __s, ios_base::openmode __wch = ios_base::out)
+ : basic_ostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(std::move(__s), __wch | ios_base::out) {}
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI basic_ostringstream(const basic_string<_CharT, _Traits, _SAlloc>& __s, const _Allocator& __a)
+ : basic_ostringstream(__s, ios_base::out, __a) {}
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI basic_ostringstream(
+ const basic_string<_CharT, _Traits, _SAlloc>& __s, ios_base::openmode __wch, const _Allocator& __a)
+ : basic_ostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__s, __wch | ios_base::out, __a) {}
+
+ template <class _SAlloc>
+ requires(!is_same_v<_SAlloc, allocator_type>)
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ostringstream(const basic_string<_CharT, _Traits, _SAlloc>& __s,
+ ios_base::openmode __wch = ios_base::out)
+ : basic_ostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__s, __wch | ios_base::out) {}
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI explicit basic_ostringstream(const _Tp& __t, ios_base::openmode __which = ios_base::out)
+ : basic_ostringstream(__t, __which | ios_base::out, _Allocator()) {}
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI basic_ostringstream(const _Tp& __t, const _Allocator& __a)
+ : basic_ostringstream(__t, ios_base::out, __a) {}
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI basic_ostringstream(const _Tp& __t, ios_base::openmode __which, const _Allocator& __a)
+ : basic_ostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__t, __which | ios_base::out, __a) {}
+
+#endif // _LIBCPP_STD_VER >= 26
+
+ basic_ostringstream(const basic_ostringstream&) = delete;
+ _LIBCPP_HIDE_FROM_ABI basic_ostringstream(basic_ostringstream&& __rhs)
+ : basic_ostream<_CharT, _Traits>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
+ basic_ostream<_CharT, _Traits>::set_rdbuf(&__sb_);
+ }
+
+ // [ostringstream.assign] Assign and swap:
+ basic_ostringstream& operator=(const basic_ostringstream&) = delete;
+ basic_ostringstream& operator=(basic_ostringstream&& __rhs) {
+ basic_ostream<char_type, traits_type>::operator=(std::move(__rhs));
+ __sb_ = std::move(__rhs.__sb_);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(basic_ostringstream& __rhs) {
+ basic_ostream<char_type, traits_type>::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+ }
+
+ // [ostringstream.members] Member functions:
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const {
+ return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
+ }
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_BUILDING_LIBRARY)
+ _LIBCPP_HIDE_FROM_ABI string_type str() const { return __sb_.str(); }
+#else
+ _LIBCPP_HIDE_FROM_ABI string_type str() const& { return __sb_.str(); }
+
+ _LIBCPP_HIDE_FROM_ABI string_type str() && { return std::move(__sb_).str(); }
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+ template <class _SAlloc>
+ requires __is_allocator<_SAlloc>::value
+ _LIBCPP_HIDE_FROM_ABI basic_string<char_type, traits_type, _SAlloc> str(const _SAlloc& __sa) const {
+ return __sb_.str(__sa);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_string_view<char_type, traits_type> view() const noexcept { return __sb_.view(); }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI void str(const string_type& __s) { __sb_.str(__s); }
+
+#if _LIBCPP_STD_VER >= 20
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI void str(const basic_string<char_type, traits_type, _SAlloc>& __s) {
+ __sb_.str(__s);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void str(string_type&& __s) { __sb_.str(std::move(__s)); }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI void str(const _Tp& __t) {
+ rdbuf()->str(__t);
+ }
+#endif // _LIBCPP_STD_VER >= 26
+};
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(basic_ostringstream<_CharT, _Traits, _Allocator>& __x, basic_ostringstream<_CharT, _Traits, _Allocator>& __y) {
+ __x.swap(__y);
+}
+
+// Class template basic_stringstream [stringstream]
+
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_TEMPLATE_VIS basic_stringstream : public basic_iostream<_CharT, _Traits> {
+public:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+ typedef _Allocator allocator_type;
+
+ typedef basic_string<char_type, traits_type, allocator_type> string_type;
+
+private:
+ basic_stringbuf<char_type, traits_type, allocator_type> __sb_;
+
+public:
+ // [stringstream.cons] constructors
+ _LIBCPP_HIDE_FROM_ABI basic_stringstream()
+ : basic_iostream<_CharT, _Traits>(&__sb_), __sb_(ios_base::in | ios_base::out) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringstream(ios_base::openmode __wch)
+ : basic_iostream<_CharT, _Traits>(&__sb_), __sb_(__wch) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringstream(const string_type& __s,
+ ios_base::openmode __wch = ios_base::in | ios_base::out)
+ : basic_iostream<_CharT, _Traits>(&__sb_), __sb_(__s, __wch) {}
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI basic_stringstream(ios_base::openmode __wch, const _Allocator& __a)
+ : basic_iostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__wch, __a) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringstream(string_type&& __s,
+ ios_base::openmode __wch = ios_base::out | ios_base::in)
+ : basic_iostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(std::move(__s), __wch) {}
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI basic_stringstream(const basic_string<_CharT, _Traits, _SAlloc>& __s, const _Allocator& __a)
+ : basic_stringstream(__s, ios_base::out | ios_base::in, __a) {}
+
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI
+ basic_stringstream(const basic_string<_CharT, _Traits, _SAlloc>& __s, ios_base::openmode __wch, const _Allocator& __a)
+ : basic_iostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__s, __wch, __a) {}
+
+ template <class _SAlloc>
+ requires(!is_same_v<_SAlloc, allocator_type>)
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringstream(const basic_string<_CharT, _Traits, _SAlloc>& __s,
+ ios_base::openmode __wch = ios_base::out | ios_base::in)
+ : basic_iostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__s, __wch) {}
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI explicit basic_stringstream(const _Tp& __t,
+ ios_base::openmode __which = ios_base::out | ios_base::in)
+ : basic_stringstream(__t, __which, _Allocator()) {}
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI basic_stringstream(const _Tp& __t, const _Allocator& __a)
+ : basic_stringstream(__t, ios_base::out | ios_base::in, __a) {}
+
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI basic_stringstream(const _Tp& __t, ios_base::openmode __which, const _Allocator& __a)
+ : basic_iostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__t, __which, __a) {}
+
+#endif // _LIBCPP_STD_VER >= 26
+
+ basic_stringstream(const basic_stringstream&) = delete;
+ _LIBCPP_HIDE_FROM_ABI basic_stringstream(basic_stringstream&& __rhs)
+ : basic_iostream<_CharT, _Traits>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
+ basic_istream<_CharT, _Traits>::set_rdbuf(&__sb_);
+ }
+
+ // [stringstream.assign] Assign and swap:
+ basic_stringstream& operator=(const basic_stringstream&) = delete;
+ basic_stringstream& operator=(basic_stringstream&& __rhs) {
+ basic_iostream<char_type, traits_type>::operator=(std::move(__rhs));
+ __sb_ = std::move(__rhs.__sb_);
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI void swap(basic_stringstream& __rhs) {
+ basic_iostream<char_type, traits_type>::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+ }
+
+ // [stringstream.members] Member functions:
+ _LIBCPP_HIDE_FROM_ABI basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const {
+ return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
+ }
+
+#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_BUILDING_LIBRARY)
+ _LIBCPP_HIDE_FROM_ABI string_type str() const { return __sb_.str(); }
+#else
+ _LIBCPP_HIDE_FROM_ABI string_type str() const& { return __sb_.str(); }
+
+ _LIBCPP_HIDE_FROM_ABI string_type str() && { return std::move(__sb_).str(); }
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+ template <class _SAlloc>
+ requires __is_allocator<_SAlloc>::value
+ _LIBCPP_HIDE_FROM_ABI basic_string<char_type, traits_type, _SAlloc> str(const _SAlloc& __sa) const {
+ return __sb_.str(__sa);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_string_view<char_type, traits_type> view() const noexcept { return __sb_.view(); }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI void str(const string_type& __s) { __sb_.str(__s); }
+
+#if _LIBCPP_STD_VER >= 20
+ template <class _SAlloc>
+ _LIBCPP_HIDE_FROM_ABI void str(const basic_string<char_type, traits_type, _SAlloc>& __s) {
+ __sb_.str(__s);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void str(string_type&& __s) { __sb_.str(std::move(__s)); }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 26
+ template <class _Tp>
+ requires is_convertible_v<const _Tp&, basic_string_view<_CharT, _Traits>>
+ _LIBCPP_HIDE_FROM_ABI void str(const _Tp& __t) {
+ rdbuf()->str(__t);
+ }
+#endif // _LIBCPP_STD_VER >= 26
+};
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(basic_stringstream<_CharT, _Traits, _Allocator>& __x, basic_stringstream<_CharT, _Traits, _Allocator>& __y) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_AVAILABILITY_HAS_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_stringbuf<char>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_stringstream<char>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostringstream<char>;
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_istringstream<char>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if _LIBCPP_STD_VER <= 20 && !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES)
+# include <ostream>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_SSTREAM
diff --git a/libcxx/include/__cxx03/stack b/libcxx/include/__cxx03/stack
new file mode 100644
index 00000000000000..90f8933cca3088
--- /dev/null
+++ b/libcxx/include/__cxx03/stack
@@ -0,0 +1,379 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STACK
+#define _LIBCPP_STACK
+
+/*
+ stack synopsis
+
+namespace std
+{
+
+template <class T, class Container = deque<T>>
+class stack
+{
+public:
+ typedef Container container_type;
+ typedef typename container_type::value_type value_type;
+ typedef typename container_type::reference reference;
+ typedef typename container_type::const_reference const_reference;
+ typedef typename container_type::size_type size_type;
+
+protected:
+ container_type c;
+
+public:
+ stack() = default;
+ ~stack() = default;
+
+ stack(const stack& q) = default;
+ stack(stack&& q) = default;
+
+ stack& operator=(const stack& q) = default;
+ stack& operator=(stack&& q) = default;
+
+ explicit stack(const container_type& c);
+ explicit stack(container_type&& c);
+ template <class InputIterator> stack(InputIterator first, InputIterator last); // since C++23
+ template<container-compatible-range<T> R> stack(from_range_t, R&& rg); // since C++23
+ template <class Alloc> explicit stack(const Alloc& a);
+ template <class Alloc> stack(const container_type& c, const Alloc& a);
+ template <class Alloc> stack(container_type&& c, const Alloc& a);
+ template <class Alloc> stack(const stack& c, const Alloc& a);
+ template <class Alloc> stack(stack&& c, const Alloc& a);
+ template<class InputIterator, class Alloc>
+ stack(InputIterator first, InputIterator last, const Alloc&); // since C++23
+ template<container-compatible-range<T> R, class Alloc>
+ stack(from_range_t, R&& rg, const Alloc&); // since C++23
+
+ bool empty() const;
+ size_type size() const;
+ reference top();
+ const_reference top() const;
+
+ void push(const value_type& x);
+ void push(value_type&& x);
+ template<container-compatible-range<T> R>
+ void push_range(R&& rg); // C++23
+ template <class... Args> reference emplace(Args&&... args); // reference in C++17
+ void pop();
+
+ void swap(stack& c) noexcept(is_nothrow_swappable_v<Container>)
+};
+
+template<class Container>
+ stack(Container) -> stack<typename Container::value_type, Container>; // C++17
+
+template<class InputIterator>
+ stack(InputIterator, InputIterator) -> stack<iter-value-type<InputIterator>>; // since C++23
+
+template<ranges::input_range R>
+ stack(from_range_t, R&&) -> stack<ranges::range_value_t<R>>; // since C++23
+
+template<class Container, class Allocator>
+ stack(Container, Allocator) -> stack<typename Container::value_type, Container>; // C++17
+
+template<class InputIterator, class Allocator>
+ stack(InputIterator, InputIterator, Allocator)
+ -> stack<iter-value-type<InputIterator>,
+ deque<iter-value-type<InputIterator>, Allocator>>; // since C++23
+
+template<ranges::input_range R, class Allocator>
+ stack(from_range_t, R&&, Allocator)
+ -> stack<ranges::range_value_t<R>, deque<ranges::range_value_t<R>, Allocator>>; // since C++23
+
+template <class T, class Container>
+ bool operator==(const stack<T, Container>& x, const stack<T, Container>& y);
+template <class T, class Container>
+ bool operator< (const stack<T, Container>& x, const stack<T, Container>& y);
+template <class T, class Container>
+ bool operator!=(const stack<T, Container>& x, const stack<T, Container>& y);
+template <class T, class Container>
+ bool operator> (const stack<T, Container>& x, const stack<T, Container>& y);
+template <class T, class Container>
+ bool operator>=(const stack<T, Container>& x, const stack<T, Container>& y);
+template <class T, class Container>
+ bool operator<=(const stack<T, Container>& x, const stack<T, Container>& y);
+template<class T, three_way_comparable Container>
+ compare_three_way_result_t<Container>
+ operator<=>(const stack<T, Container>& x, const stack<T, Container>& y); // since C++20
+
+template <class T, class Container>
+ void swap(stack<T, Container>& x, stack<T, Container>& y)
+ noexcept(noexcept(x.swap(y)));
+
+} // std
+
+*/
+
+#include <__algorithm/ranges_copy.h>
+#include <__config>
+#include <__fwd/stack.h>
+#include <__iterator/back_insert_iterator.h>
+#include <__iterator/iterator_traits.h>
+#include <__memory/uses_allocator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__type_traits/is_same.h>
+#include <__utility/forward.h>
+#include <deque>
+#include <version>
+
+// standard-mandated includes
+
+// [stack.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Container>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y);
+
+template <class _Tp, class _Container>
+_LIBCPP_HIDE_FROM_ABI bool operator<(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y);
+
+template <class _Tp, class _Container /*= deque<_Tp>*/>
+class _LIBCPP_TEMPLATE_VIS stack {
+public:
+ typedef _Container container_type;
+ typedef typename container_type::value_type value_type;
+ typedef typename container_type::reference reference;
+ typedef typename container_type::const_reference const_reference;
+ typedef typename container_type::size_type size_type;
+ static_assert(is_same<_Tp, value_type>::value, "");
+
+protected:
+ container_type c;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI stack() _NOEXCEPT_(is_nothrow_default_constructible<container_type>::value) : c() {}
+
+ _LIBCPP_HIDE_FROM_ABI stack(const stack& __q) : c(__q.c) {}
+
+ _LIBCPP_HIDE_FROM_ABI stack& operator=(const stack& __q) {
+ c = __q.c;
+ return *this;
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI stack(stack&& __q) noexcept(is_nothrow_move_constructible<container_type>::value)
+ : c(std::move(__q.c)) {}
+
+ _LIBCPP_HIDE_FROM_ABI stack& operator=(stack&& __q) noexcept(is_nothrow_move_assignable<container_type>::value) {
+ c = std::move(__q.c);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit stack(container_type&& __c) : c(std::move(__c)) {}
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI explicit stack(const container_type& __c) : c(__c) {}
+
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI explicit stack(const _Alloc& __a,
+ __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
+ : c(__a) {}
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI
+ stack(const container_type& __c, const _Alloc& __a, __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
+ : c(__c, __a) {}
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI
+ stack(const stack& __s, const _Alloc& __a, __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
+ : c(__s.c, __a) {}
+#ifndef _LIBCPP_CXX03_LANG
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI
+ stack(container_type&& __c, const _Alloc& __a, __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
+ : c(std::move(__c), __a) {}
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI
+ stack(stack&& __s, const _Alloc& __a, __enable_if_t<uses_allocator<container_type, _Alloc>::value>* = 0)
+ : c(std::move(__s.c), __a) {}
+#endif // _LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 23
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI stack(_InputIterator __first, _InputIterator __last) : c(__first, __last) {}
+
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI stack(from_range_t, _Range&& __range) : c(from_range, std::forward<_Range>(__range)) {}
+
+ template <class _InputIterator,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0,
+ __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI stack(_InputIterator __first, _InputIterator __last, const _Alloc& __alloc)
+ : c(__first, __last, __alloc) {}
+
+ template <_ContainerCompatibleRange<_Tp> _Range,
+ class _Alloc,
+ __enable_if_t<uses_allocator<container_type, _Alloc>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI stack(from_range_t, _Range&& __range, const _Alloc& __alloc)
+ : c(from_range, std::forward<_Range>(__range), __alloc) {}
+
+#endif
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const { return c.empty(); }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const { return c.size(); }
+ _LIBCPP_HIDE_FROM_ABI reference top() { return c.back(); }
+ _LIBCPP_HIDE_FROM_ABI const_reference top() const { return c.back(); }
+
+ _LIBCPP_HIDE_FROM_ABI void push(const value_type& __v) { c.push_back(__v); }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void push(value_type&& __v) { c.push_back(std::move(__v)); }
+
+# if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI void push_range(_Range&& __range) {
+ if constexpr (requires(container_type& __c) { __c.append_range(std::forward<_Range>(__range)); }) {
+ c.append_range(std::forward<_Range>(__range));
+ } else {
+ ranges::copy(std::forward<_Range>(__range), std::back_inserter(c));
+ }
+ }
+# endif
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI
+# if _LIBCPP_STD_VER >= 17
+ decltype(auto)
+ emplace(_Args&&... __args) {
+ return c.emplace_back(std::forward<_Args>(__args)...);
+ }
+# else
+ void
+ emplace(_Args&&... __args) {
+ c.emplace_back(std::forward<_Args>(__args)...);
+ }
+# endif
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI void pop() { c.pop_back(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(stack& __s) _NOEXCEPT_(__is_nothrow_swappable_v<container_type>) {
+ using std::swap;
+ swap(c, __s.c);
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI const _Container& __get_container() const { return c; }
+
+ template <class _T1, class _OtherContainer>
+ friend bool operator==(const stack<_T1, _OtherContainer>& __x, const stack<_T1, _OtherContainer>& __y);
+
+ template <class _T1, class _OtherContainer>
+ friend bool operator<(const stack<_T1, _OtherContainer>& __x, const stack<_T1, _OtherContainer>& __y);
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Container, class = enable_if_t<!__is_allocator<_Container>::value> >
+stack(_Container) -> stack<typename _Container::value_type, _Container>;
+
+template <class _Container,
+ class _Alloc,
+ class = enable_if_t<!__is_allocator<_Container>::value>,
+ class = enable_if_t<uses_allocator<_Container, _Alloc>::value> >
+stack(_Container, _Alloc) -> stack<typename _Container::value_type, _Container>;
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+stack(_InputIterator, _InputIterator) -> stack<__iter_value_type<_InputIterator>>;
+
+template <ranges::input_range _Range>
+stack(from_range_t, _Range&&) -> stack<ranges::range_value_t<_Range>>;
+
+template <class _InputIterator,
+ class _Alloc,
+ __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0,
+ __enable_if_t<__is_allocator<_Alloc>::value, int> = 0>
+stack(_InputIterator,
+ _InputIterator,
+ _Alloc) -> stack<__iter_value_type<_InputIterator>, deque<__iter_value_type<_InputIterator>, _Alloc>>;
+
+template <ranges::input_range _Range, class _Alloc, __enable_if_t<__is_allocator<_Alloc>::value, int> = 0>
+stack(from_range_t,
+ _Range&&,
+ _Alloc) -> stack<ranges::range_value_t<_Range>, deque<ranges::range_value_t<_Range>, _Alloc>>;
+
+#endif
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator==(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y) {
+ return __x.c == __y.c;
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y) {
+ return __x.c < __y.c;
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y) {
+ return __y < __x;
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Tp, class _Container>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y) {
+ return !(__y < __x);
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Tp, three_way_comparable _Container>
+_LIBCPP_HIDE_FROM_ABI compare_three_way_result_t<_Container>
+operator<=>(const stack<_Tp, _Container>& __x, const stack<_Tp, _Container>& __y) {
+ // clang 16 bug: declaring `friend operator<=>` causes "use of overloaded operator '*' is ambiguous" errors
+ return __x.__get_container() <=> __y.__get_container();
+}
+
+#endif
+
+template <class _Tp, class _Container, __enable_if_t<__is_swappable_v<_Container>, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI void swap(stack<_Tp, _Container>& __x, stack<_Tp, _Container>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+template <class _Tp, class _Container, class _Alloc>
+struct _LIBCPP_TEMPLATE_VIS uses_allocator<stack<_Tp, _Container>, _Alloc> : public uses_allocator<_Container, _Alloc> {
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <functional>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_STACK
diff --git a/libcxx/include/__cxx03/stdatomic.h b/libcxx/include/__cxx03/stdatomic.h
new file mode 100644
index 00000000000000..79772eb7fce1f5
--- /dev/null
+++ b/libcxx/include/__cxx03/stdatomic.h
@@ -0,0 +1,235 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STDATOMIC_H
+#define _LIBCPP_STDATOMIC_H
+
+/*
+ stdatomic.h synopsis
+
+template<class T>
+ using std-atomic = std::atomic<T>; // exposition only
+
+#define _Atomic(T) std-atomic<T>
+
+#define ATOMIC_BOOL_LOCK_FREE see below
+#define ATOMIC_CHAR_LOCK_FREE see below
+#define ATOMIC_CHAR16_T_LOCK_FREE see below
+#define ATOMIC_CHAR32_T_LOCK_FREE see below
+#define ATOMIC_WCHAR_T_LOCK_FREE see below
+#define ATOMIC_SHORT_LOCK_FREE see below
+#define ATOMIC_INT_LOCK_FREE see below
+#define ATOMIC_LONG_LOCK_FREE see below
+#define ATOMIC_LLONG_LOCK_FREE see below
+#define ATOMIC_POINTER_LOCK_FREE see below
+
+using std::memory_order // see below
+using std::memory_order_relaxed // see below
+using std::memory_order_consume // see below
+using std::memory_order_acquire // see below
+using std::memory_order_release // see below
+using std::memory_order_acq_rel // see below
+using std::memory_order_seq_cst // see below
+
+using std::atomic_flag // see below
+
+using std::atomic_bool // see below
+using std::atomic_char // see below
+using std::atomic_schar // see below
+using std::atomic_uchar // see below
+using std::atomic_short // see below
+using std::atomic_ushort // see below
+using std::atomic_int // see below
+using std::atomic_uint // see below
+using std::atomic_long // see below
+using std::atomic_ulong // see below
+using std::atomic_llong // see below
+using std::atomic_ullong // see below
+using std::atomic_char8_t // see below
+using std::atomic_char16_t // see below
+using std::atomic_char32_t // see below
+using std::atomic_wchar_t // see below
+using std::atomic_int8_t // see below
+using std::atomic_uint8_t // see below
+using std::atomic_int16_t // see below
+using std::atomic_uint16_t // see below
+using std::atomic_int32_t // see below
+using std::atomic_uint32_t // see below
+using std::atomic_int64_t // see below
+using std::atomic_uint64_t // see below
+using std::atomic_int_least8_t // see below
+using std::atomic_uint_least8_t // see below
+using std::atomic_int_least16_t // see below
+using std::atomic_uint_least16_t // see below
+using std::atomic_int_least32_t // see below
+using std::atomic_uint_least32_t // see below
+using std::atomic_int_least64_t // see below
+using std::atomic_uint_least64_t // see below
+using std::atomic_int_fast8_t // see below
+using std::atomic_uint_fast8_t // see below
+using std::atomic_int_fast16_t // see below
+using std::atomic_uint_fast16_t // see below
+using std::atomic_int_fast32_t // see below
+using std::atomic_uint_fast32_t // see below
+using std::atomic_int_fast64_t // see below
+using std::atomic_uint_fast64_t // see below
+using std::atomic_intptr_t // see below
+using std::atomic_uintptr_t // see below
+using std::atomic_size_t // see below
+using std::atomic_ptrdiff_t // see below
+using std::atomic_intmax_t // see below
+using std::atomic_uintmax_t // see below
+
+using std::atomic_is_lock_free // see below
+using std::atomic_load // see below
+using std::atomic_load_explicit // see below
+using std::atomic_store // see below
+using std::atomic_store_explicit // see below
+using std::atomic_exchange // see below
+using std::atomic_exchange_explicit // see below
+using std::atomic_compare_exchange_strong // see below
+using std::atomic_compare_exchange_strong_explicit // see below
+using std::atomic_compare_exchange_weak // see below
+using std::atomic_compare_exchange_weak_explicit // see below
+using std::atomic_fetch_add // see below
+using std::atomic_fetch_add_explicit // see below
+using std::atomic_fetch_sub // see below
+using std::atomic_fetch_sub_explicit // see below
+using std::atomic_fetch_or // see below
+using std::atomic_fetch_or_explicit // see below
+using std::atomic_fetch_and // see below
+using std::atomic_fetch_and_explicit // see below
+using std::atomic_flag_test_and_set // see below
+using std::atomic_flag_test_and_set_explicit // see below
+using std::atomic_flag_clear // see below
+using std::atomic_flag_clear_explicit // see below
+
+using std::atomic_thread_fence // see below
+using std::atomic_signal_fence // see below
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if defined(__cplusplus) && _LIBCPP_STD_VER >= 23
+
+# include <atomic>
+# include <version>
+
+# ifdef _Atomic
+# undef _Atomic
+# endif
+
+# define _Atomic(_Tp) ::std::atomic<_Tp>
+
+using std::memory_order _LIBCPP_USING_IF_EXISTS;
+using std::memory_order_relaxed _LIBCPP_USING_IF_EXISTS;
+using std::memory_order_consume _LIBCPP_USING_IF_EXISTS;
+using std::memory_order_acquire _LIBCPP_USING_IF_EXISTS;
+using std::memory_order_release _LIBCPP_USING_IF_EXISTS;
+using std::memory_order_acq_rel _LIBCPP_USING_IF_EXISTS;
+using std::memory_order_seq_cst _LIBCPP_USING_IF_EXISTS;
+
+using std::atomic_flag _LIBCPP_USING_IF_EXISTS;
+
+using std::atomic_bool _LIBCPP_USING_IF_EXISTS;
+using std::atomic_char _LIBCPP_USING_IF_EXISTS;
+using std::atomic_schar _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uchar _LIBCPP_USING_IF_EXISTS;
+using std::atomic_short _LIBCPP_USING_IF_EXISTS;
+using std::atomic_ushort _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint _LIBCPP_USING_IF_EXISTS;
+using std::atomic_long _LIBCPP_USING_IF_EXISTS;
+using std::atomic_ulong _LIBCPP_USING_IF_EXISTS;
+using std::atomic_llong _LIBCPP_USING_IF_EXISTS;
+using std::atomic_ullong _LIBCPP_USING_IF_EXISTS;
+using std::atomic_char8_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_char16_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_char32_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_wchar_t _LIBCPP_USING_IF_EXISTS;
+
+using std::atomic_int8_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint8_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int16_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint16_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int32_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint32_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int64_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint64_t _LIBCPP_USING_IF_EXISTS;
+
+using std::atomic_int_least8_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint_least8_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int_least16_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint_least16_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int_least32_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint_least32_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int_least64_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint_least64_t _LIBCPP_USING_IF_EXISTS;
+
+using std::atomic_int_fast8_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint_fast8_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int_fast16_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint_fast16_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int_fast32_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint_fast32_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_int_fast64_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uint_fast64_t _LIBCPP_USING_IF_EXISTS;
+
+using std::atomic_intptr_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uintptr_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_size_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_ptrdiff_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_intmax_t _LIBCPP_USING_IF_EXISTS;
+using std::atomic_uintmax_t _LIBCPP_USING_IF_EXISTS;
+
+using std::atomic_compare_exchange_strong _LIBCPP_USING_IF_EXISTS;
+using std::atomic_compare_exchange_strong_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_compare_exchange_weak _LIBCPP_USING_IF_EXISTS;
+using std::atomic_compare_exchange_weak_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_exchange _LIBCPP_USING_IF_EXISTS;
+using std::atomic_exchange_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_fetch_add _LIBCPP_USING_IF_EXISTS;
+using std::atomic_fetch_add_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_fetch_and _LIBCPP_USING_IF_EXISTS;
+using std::atomic_fetch_and_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_fetch_or _LIBCPP_USING_IF_EXISTS;
+using std::atomic_fetch_or_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_fetch_sub _LIBCPP_USING_IF_EXISTS;
+using std::atomic_fetch_sub_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_flag_clear _LIBCPP_USING_IF_EXISTS;
+using std::atomic_flag_clear_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_flag_test_and_set _LIBCPP_USING_IF_EXISTS;
+using std::atomic_flag_test_and_set_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_is_lock_free _LIBCPP_USING_IF_EXISTS;
+using std::atomic_load _LIBCPP_USING_IF_EXISTS;
+using std::atomic_load_explicit _LIBCPP_USING_IF_EXISTS;
+using std::atomic_store _LIBCPP_USING_IF_EXISTS;
+using std::atomic_store_explicit _LIBCPP_USING_IF_EXISTS;
+
+using std::atomic_signal_fence _LIBCPP_USING_IF_EXISTS;
+using std::atomic_thread_fence _LIBCPP_USING_IF_EXISTS;
+
+#elif defined(_LIBCPP_COMPILER_CLANG_BASED)
+
+// Before C++23, we include the next <stdatomic.h> on the path to avoid hijacking
+// the header. We do this because Clang has historically shipped a <stdatomic.h>
+// header that would be available in all Standard modes, and we don't want to
+// break that use case.
+# if __has_include_next(<stdatomic.h>)
+# include_next <stdatomic.h>
+# endif
+
+#endif // defined(__cplusplus) && _LIBCPP_STD_VER >= 23
+
+#endif // _LIBCPP_STDATOMIC_H
diff --git a/libcxx/include/__cxx03/stdbool.h b/libcxx/include/__cxx03/stdbool.h
new file mode 100644
index 00000000000000..e74d91f4594592
--- /dev/null
+++ b/libcxx/include/__cxx03/stdbool.h
@@ -0,0 +1,40 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STDBOOL_H
+#define _LIBCPP_STDBOOL_H
+
+/*
+ stdbool.h synopsis
+
+Macros:
+
+ __bool_true_false_are_defined
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if __has_include_next(<stdbool.h>)
+# include_next <stdbool.h>
+#endif
+
+#ifdef __cplusplus
+# undef bool
+# undef true
+# undef false
+# undef __bool_true_false_are_defined
+# define __bool_true_false_are_defined 1
+#endif
+
+#endif // _LIBCPP_STDBOOL_H
diff --git a/libcxx/include/__cxx03/stddef.h b/libcxx/include/__cxx03/stddef.h
new file mode 100644
index 00000000000000..1583e78e3739ba
--- /dev/null
+++ b/libcxx/include/__cxx03/stddef.h
@@ -0,0 +1,44 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+/*
+ stddef.h synopsis
+
+Macros:
+
+ offsetof(type,member-designator)
+ NULL
+
+Types:
+
+ ptrdiff_t
+ size_t
+ max_align_t // C++11
+ nullptr_t
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// Note: This include is outside of header guards because we sometimes get included multiple times
+// with different defines and the underlying <stddef.h> will know how to deal with that.
+#include_next <stddef.h>
+
+#ifndef _LIBCPP_STDDEF_H
+# define _LIBCPP_STDDEF_H
+
+# ifdef __cplusplus
+typedef decltype(nullptr) nullptr_t;
+# endif
+
+#endif // _LIBCPP_STDDEF_H
diff --git a/libcxx/include/__cxx03/stdexcept b/libcxx/include/__cxx03/stdexcept
new file mode 100644
index 00000000000000..853c185187c778
--- /dev/null
+++ b/libcxx/include/__cxx03/stdexcept
@@ -0,0 +1,286 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STDEXCEPT
+#define _LIBCPP_STDEXCEPT
+
+/*
+ stdexcept synopsis
+
+namespace std
+{
+
+class logic_error;
+class domain_error;
+class invalid_argument;
+class length_error;
+class out_of_range;
+class runtime_error;
+class range_error;
+class overflow_error;
+class underflow_error;
+
+for each class xxx_error:
+
+class xxx_error : public exception // at least indirectly
+{
+public:
+ explicit xxx_error(const string& what_arg);
+ explicit xxx_error(const char* what_arg);
+
+ virtual const char* what() const noexcept // returns what_arg
+};
+
+} // std
+
+*/
+
+#include <__config>
+#include <__exception/exception.h>
+#include <__fwd/string.h>
+#include <__verbose_abort>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_ABI_VCRUNTIME
+class _LIBCPP_HIDDEN __libcpp_refstring {
+ const char* __imp_;
+
+ bool __uses_refcount() const;
+
+public:
+ explicit __libcpp_refstring(const char* __msg);
+ __libcpp_refstring(const __libcpp_refstring& __s) _NOEXCEPT;
+ __libcpp_refstring& operator=(const __libcpp_refstring& __s) _NOEXCEPT;
+ ~__libcpp_refstring();
+
+ _LIBCPP_HIDE_FROM_ABI const char* c_str() const _NOEXCEPT { return __imp_; }
+};
+#endif // !_LIBCPP_ABI_VCRUNTIME
+
+_LIBCPP_END_NAMESPACE_STD
+
+namespace std // purposefully not using versioning namespace
+{
+
+class _LIBCPP_EXPORTED_FROM_ABI logic_error : public exception {
+#ifndef _LIBCPP_ABI_VCRUNTIME
+
+private:
+ std::__libcpp_refstring __imp_;
+
+public:
+ explicit logic_error(const string&);
+ explicit logic_error(const char*);
+
+ logic_error(const logic_error&) _NOEXCEPT;
+ logic_error& operator=(const logic_error&) _NOEXCEPT;
+
+ ~logic_error() _NOEXCEPT override;
+
+ const char* what() const _NOEXCEPT override;
+#else
+
+public:
+ explicit logic_error(const std::string&); // Symbol uses versioned std::string
+ _LIBCPP_HIDE_FROM_ABI explicit logic_error(const char* __s) : exception(__s) {}
+#endif
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI runtime_error : public exception {
+#ifndef _LIBCPP_ABI_VCRUNTIME
+
+private:
+ std::__libcpp_refstring __imp_;
+
+public:
+ explicit runtime_error(const string&);
+ explicit runtime_error(const char*);
+
+ runtime_error(const runtime_error&) _NOEXCEPT;
+ runtime_error& operator=(const runtime_error&) _NOEXCEPT;
+
+ ~runtime_error() _NOEXCEPT override;
+
+ const char* what() const _NOEXCEPT override;
+#else
+
+public:
+ explicit runtime_error(const std::string&); // Symbol uses versioned std::string
+ _LIBCPP_HIDE_FROM_ABI explicit runtime_error(const char* __s) : exception(__s) {}
+#endif // _LIBCPP_ABI_VCRUNTIME
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI domain_error : public logic_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit domain_error(const string& __s) : logic_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI explicit domain_error(const char* __s) : logic_error(__s) {}
+
+#ifndef _LIBCPP_ABI_VCRUNTIME
+ _LIBCPP_HIDE_FROM_ABI domain_error(const domain_error&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI domain_error& operator=(const domain_error&) _NOEXCEPT = default;
+ ~domain_error() _NOEXCEPT override;
+#endif
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI invalid_argument : public logic_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit invalid_argument(const string& __s) : logic_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI explicit invalid_argument(const char* __s) : logic_error(__s) {}
+
+#ifndef _LIBCPP_ABI_VCRUNTIME
+ _LIBCPP_HIDE_FROM_ABI invalid_argument(const invalid_argument&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI invalid_argument& operator=(const invalid_argument&) _NOEXCEPT = default;
+ ~invalid_argument() _NOEXCEPT override;
+#endif
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI length_error : public logic_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit length_error(const string& __s) : logic_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI explicit length_error(const char* __s) : logic_error(__s) {}
+#ifndef _LIBCPP_ABI_VCRUNTIME
+ _LIBCPP_HIDE_FROM_ABI length_error(const length_error&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI length_error& operator=(const length_error&) _NOEXCEPT = default;
+ ~length_error() _NOEXCEPT override;
+#endif
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI out_of_range : public logic_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit out_of_range(const string& __s) : logic_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI explicit out_of_range(const char* __s) : logic_error(__s) {}
+
+#ifndef _LIBCPP_ABI_VCRUNTIME
+ _LIBCPP_HIDE_FROM_ABI out_of_range(const out_of_range&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI out_of_range& operator=(const out_of_range&) _NOEXCEPT = default;
+ ~out_of_range() _NOEXCEPT override;
+#endif
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI range_error : public runtime_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit range_error(const string& __s) : runtime_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI explicit range_error(const char* __s) : runtime_error(__s) {}
+
+#ifndef _LIBCPP_ABI_VCRUNTIME
+ _LIBCPP_HIDE_FROM_ABI range_error(const range_error&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI range_error& operator=(const range_error&) _NOEXCEPT = default;
+ ~range_error() _NOEXCEPT override;
+#endif
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI overflow_error : public runtime_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit overflow_error(const string& __s) : runtime_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI explicit overflow_error(const char* __s) : runtime_error(__s) {}
+
+#ifndef _LIBCPP_ABI_VCRUNTIME
+ _LIBCPP_HIDE_FROM_ABI overflow_error(const overflow_error&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI overflow_error& operator=(const overflow_error&) _NOEXCEPT = default;
+ ~overflow_error() _NOEXCEPT override;
+#endif
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI underflow_error : public runtime_error {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit underflow_error(const string& __s) : runtime_error(__s) {}
+ _LIBCPP_HIDE_FROM_ABI explicit underflow_error(const char* __s) : runtime_error(__s) {}
+
+#ifndef _LIBCPP_ABI_VCRUNTIME
+ _LIBCPP_HIDE_FROM_ABI underflow_error(const underflow_error&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI underflow_error& operator=(const underflow_error&) _NOEXCEPT = default;
+ ~underflow_error() _NOEXCEPT override;
+#endif
+};
+
+} // namespace std
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// in the dylib
+_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void __throw_runtime_error(const char*);
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_logic_error(const char* __msg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw logic_error(__msg);
+#else
+ _LIBCPP_VERBOSE_ABORT("logic_error was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+#endif
+}
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_domain_error(const char* __msg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw domain_error(__msg);
+#else
+ _LIBCPP_VERBOSE_ABORT("domain_error was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+#endif
+}
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_invalid_argument(const char* __msg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw invalid_argument(__msg);
+#else
+ _LIBCPP_VERBOSE_ABORT("invalid_argument was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+#endif
+}
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_length_error(const char* __msg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw length_error(__msg);
+#else
+ _LIBCPP_VERBOSE_ABORT("length_error was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+#endif
+}
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_out_of_range(const char* __msg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw out_of_range(__msg);
+#else
+ _LIBCPP_VERBOSE_ABORT("out_of_range was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+#endif
+}
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_range_error(const char* __msg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw range_error(__msg);
+#else
+ _LIBCPP_VERBOSE_ABORT("range_error was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+#endif
+}
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_overflow_error(const char* __msg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw overflow_error(__msg);
+#else
+ _LIBCPP_VERBOSE_ABORT("overflow_error was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+#endif
+}
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_underflow_error(const char* __msg) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw underflow_error(__msg);
+#else
+ _LIBCPP_VERBOSE_ABORT("underflow_error was thrown in -fno-exceptions mode with message \"%s\"", __msg);
+#endif
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdlib>
+# include <exception>
+# include <iosfwd>
+#endif
+
+#endif // _LIBCPP_STDEXCEPT
diff --git a/libcxx/include/__cxx03/stdint.h b/libcxx/include/__cxx03/stdint.h
new file mode 100644
index 00000000000000..35e5b8cbdad264
--- /dev/null
+++ b/libcxx/include/__cxx03/stdint.h
@@ -0,0 +1,127 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STDINT_H
+// AIX system headers need stdint.h to be re-enterable while _STD_TYPES_T
+// is defined until an inclusion of it without _STD_TYPES_T occurs, in which
+// case the header guard macro is defined.
+#if !defined(_AIX) || !defined(_STD_TYPES_T)
+# define _LIBCPP_STDINT_H
+#endif // _STD_TYPES_T
+
+/*
+ stdint.h synopsis
+
+Macros:
+
+ INT8_MIN
+ INT16_MIN
+ INT32_MIN
+ INT64_MIN
+
+ INT8_MAX
+ INT16_MAX
+ INT32_MAX
+ INT64_MAX
+
+ UINT8_MAX
+ UINT16_MAX
+ UINT32_MAX
+ UINT64_MAX
+
+ INT_LEAST8_MIN
+ INT_LEAST16_MIN
+ INT_LEAST32_MIN
+ INT_LEAST64_MIN
+
+ INT_LEAST8_MAX
+ INT_LEAST16_MAX
+ INT_LEAST32_MAX
+ INT_LEAST64_MAX
+
+ UINT_LEAST8_MAX
+ UINT_LEAST16_MAX
+ UINT_LEAST32_MAX
+ UINT_LEAST64_MAX
+
+ INT_FAST8_MIN
+ INT_FAST16_MIN
+ INT_FAST32_MIN
+ INT_FAST64_MIN
+
+ INT_FAST8_MAX
+ INT_FAST16_MAX
+ INT_FAST32_MAX
+ INT_FAST64_MAX
+
+ UINT_FAST8_MAX
+ UINT_FAST16_MAX
+ UINT_FAST32_MAX
+ UINT_FAST64_MAX
+
+ INTPTR_MIN
+ INTPTR_MAX
+ UINTPTR_MAX
+
+ INTMAX_MIN
+ INTMAX_MAX
+
+ UINTMAX_MAX
+
+ PTRDIFF_MIN
+ PTRDIFF_MAX
+
+ SIG_ATOMIC_MIN
+ SIG_ATOMIC_MAX
+
+ SIZE_MAX
+
+ WCHAR_MIN
+ WCHAR_MAX
+
+ WINT_MIN
+ WINT_MAX
+
+ INT8_C(value)
+ INT16_C(value)
+ INT32_C(value)
+ INT64_C(value)
+
+ UINT8_C(value)
+ UINT16_C(value)
+ UINT32_C(value)
+ UINT64_C(value)
+
+ INTMAX_C(value)
+ UINTMAX_C(value)
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+/* C99 stdlib (e.g. glibc < 2.18) does not provide macros needed
+ for C++11 unless __STDC_LIMIT_MACROS and __STDC_CONSTANT_MACROS
+ are defined
+*/
+#if defined(__cplusplus) && !defined(__STDC_LIMIT_MACROS)
+# define __STDC_LIMIT_MACROS
+#endif
+#if defined(__cplusplus) && !defined(__STDC_CONSTANT_MACROS)
+# define __STDC_CONSTANT_MACROS
+#endif
+
+#if __has_include_next(<stdint.h>)
+# include_next <stdint.h>
+#endif
+
+#endif // _LIBCPP_STDINT_H
diff --git a/libcxx/include/__cxx03/stdio.h b/libcxx/include/__cxx03/stdio.h
new file mode 100644
index 00000000000000..3aa559393f1853
--- /dev/null
+++ b/libcxx/include/__cxx03/stdio.h
@@ -0,0 +1,123 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#if defined(__need_FILE) || defined(__need___FILE)
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+# include_next <stdio.h>
+
+#elif !defined(_LIBCPP_STDIO_H)
+# define _LIBCPP_STDIO_H
+
+/*
+ stdio.h synopsis
+
+Macros:
+
+ BUFSIZ
+ EOF
+ FILENAME_MAX
+ FOPEN_MAX
+ L_tmpnam
+ NULL
+ SEEK_CUR
+ SEEK_END
+ SEEK_SET
+ TMP_MAX
+ _IOFBF
+ _IOLBF
+ _IONBF
+ stderr
+ stdin
+ stdout
+
+Types:
+
+FILE
+fpos_t
+size_t
+
+int remove(const char* filename);
+int rename(const char* old, const char* new);
+FILE* tmpfile(void);
+char* tmpnam(char* s);
+int fclose(FILE* stream);
+int fflush(FILE* stream);
+FILE* fopen(const char* restrict filename, const char* restrict mode);
+FILE* freopen(const char* restrict filename, const char * restrict mode,
+ FILE * restrict stream);
+void setbuf(FILE* restrict stream, char* restrict buf);
+int setvbuf(FILE* restrict stream, char* restrict buf, int mode, size_t size);
+int fprintf(FILE* restrict stream, const char* restrict format, ...);
+int fscanf(FILE* restrict stream, const char * restrict format, ...);
+int printf(const char* restrict format, ...);
+int scanf(const char* restrict format, ...);
+int snprintf(char* restrict s, size_t n, const char* restrict format, ...); // C99
+int sprintf(char* restrict s, const char* restrict format, ...);
+int sscanf(const char* restrict s, const char* restrict format, ...);
+int vfprintf(FILE* restrict stream, const char* restrict format, va_list arg);
+int vfscanf(FILE* restrict stream, const char* restrict format, va_list arg); // C99
+int vprintf(const char* restrict format, va_list arg);
+int vscanf(const char* restrict format, va_list arg); // C99
+int vsnprintf(char* restrict s, size_t n, const char* restrict format, // C99
+ va_list arg);
+int vsprintf(char* restrict s, const char* restrict format, va_list arg);
+int vsscanf(const char* restrict s, const char* restrict format, va_list arg); // C99
+int fgetc(FILE* stream);
+char* fgets(char* restrict s, int n, FILE* restrict stream);
+int fputc(int c, FILE* stream);
+int fputs(const char* restrict s, FILE* restrict stream);
+int getc(FILE* stream);
+int getchar(void);
+char* gets(char* s); // removed in C++14
+int putc(int c, FILE* stream);
+int putchar(int c);
+int puts(const char* s);
+int ungetc(int c, FILE* stream);
+size_t fread(void* restrict ptr, size_t size, size_t nmemb,
+ FILE* restrict stream);
+size_t fwrite(const void* restrict ptr, size_t size, size_t nmemb,
+ FILE* restrict stream);
+int fgetpos(FILE* restrict stream, fpos_t* restrict pos);
+int fseek(FILE* stream, long offset, int whence);
+int fsetpos(FILE*stream, const fpos_t* pos);
+long ftell(FILE* stream);
+void rewind(FILE* stream);
+void clearerr(FILE* stream);
+int feof(FILE* stream);
+int ferror(FILE* stream);
+void perror(const char* s);
+*/
+
+# include <__config>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+# if __has_include_next(<stdio.h>)
+# include_next <stdio.h>
+# endif
+
+# ifdef __cplusplus
+
+# undef getc
+# undef putc
+# undef clearerr
+# undef feof
+# undef ferror
+# undef putchar
+# undef getchar
+
+# endif
+
+#endif // _LIBCPP_STDIO_H
diff --git a/libcxx/include/__cxx03/stdlib.h b/libcxx/include/__cxx03/stdlib.h
new file mode 100644
index 00000000000000..a74344d49150c1
--- /dev/null
+++ b/libcxx/include/__cxx03/stdlib.h
@@ -0,0 +1,151 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#if defined(__need_malloc_and_calloc)
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+# include_next <stdlib.h>
+
+#elif !defined(_LIBCPP_STDLIB_H)
+# define _LIBCPP_STDLIB_H
+
+/*
+ stdlib.h synopsis
+
+Macros:
+
+ EXIT_FAILURE
+ EXIT_SUCCESS
+ MB_CUR_MAX
+ NULL
+ RAND_MAX
+
+Types:
+
+ size_t
+ div_t
+ ldiv_t
+ lldiv_t // C99
+
+double atof (const char* nptr);
+int atoi (const char* nptr);
+long atol (const char* nptr);
+long long atoll(const char* nptr); // C99
+double strtod (const char* restrict nptr, char** restrict endptr);
+float strtof (const char* restrict nptr, char** restrict endptr); // C99
+long double strtold (const char* restrict nptr, char** restrict endptr); // C99
+long strtol (const char* restrict nptr, char** restrict endptr, int base);
+long long strtoll (const char* restrict nptr, char** restrict endptr, int base); // C99
+unsigned long strtoul (const char* restrict nptr, char** restrict endptr, int base);
+unsigned long long strtoull(const char* restrict nptr, char** restrict endptr, int base); // C99
+int rand(void);
+void srand(unsigned int seed);
+void* calloc(size_t nmemb, size_t size);
+void free(void* ptr);
+void* malloc(size_t size);
+void* realloc(void* ptr, size_t size);
+void abort(void);
+int atexit(void (*func)(void));
+void exit(int status);
+void _Exit(int status);
+char* getenv(const char* name);
+int system(const char* string);
+void* bsearch(const void* key, const void* base, size_t nmemb, size_t size,
+ int (*compar)(const void *, const void *));
+void qsort(void* base, size_t nmemb, size_t size,
+ int (*compar)(const void *, const void *));
+int abs( int j);
+long abs( long j);
+long long abs(long long j); // C++0X
+long labs( long j);
+long long llabs(long long j); // C99
+div_t div( int numer, int denom);
+ldiv_t div( long numer, long denom);
+lldiv_t div(long long numer, long long denom); // C++0X
+ldiv_t ldiv( long numer, long denom);
+lldiv_t lldiv(long long numer, long long denom); // C99
+int mblen(const char* s, size_t n);
+int mbtowc(wchar_t* restrict pwc, const char* restrict s, size_t n);
+int wctomb(char* s, wchar_t wchar);
+size_t mbstowcs(wchar_t* restrict pwcs, const char* restrict s, size_t n);
+size_t wcstombs(char* restrict s, const wchar_t* restrict pwcs, size_t n);
+int at_quick_exit(void (*func)(void)) // C++11
+void quick_exit(int status); // C++11
+void *aligned_alloc(size_t alignment, size_t size); // C11
+
+*/
+
+# include <__config>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+# if __has_include_next(<stdlib.h>)
+# include_next <stdlib.h>
+# endif
+
+# ifdef __cplusplus
+extern "C++" {
+// abs
+
+# ifdef abs
+# undef abs
+# endif
+# ifdef labs
+# undef labs
+# endif
+# ifdef llabs
+# undef llabs
+# endif
+
+// MSVCRT already has the correct prototype in <stdlib.h> if __cplusplus is defined
+# if !defined(_LIBCPP_MSVCRT)
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long abs(long __x) _NOEXCEPT { return __builtin_labs(__x); }
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long long abs(long long __x) _NOEXCEPT { return __builtin_llabs(__x); }
+# endif // !defined(_LIBCPP_MSVCRT)
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI float abs(float __lcpp_x) _NOEXCEPT {
+ return __builtin_fabsf(__lcpp_x); // Use builtins to prevent needing math.h
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI double abs(double __lcpp_x) _NOEXCEPT {
+ return __builtin_fabs(__lcpp_x);
+}
+
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI long double abs(long double __lcpp_x) _NOEXCEPT {
+ return __builtin_fabsl(__lcpp_x);
+}
+
+// div
+
+# ifdef div
+# undef div
+# endif
+# ifdef ldiv
+# undef ldiv
+# endif
+# ifdef lldiv
+# undef lldiv
+# endif
+
+// MSVCRT already has the correct prototype in <stdlib.h> if __cplusplus is defined
+# if !defined(_LIBCPP_MSVCRT)
+inline _LIBCPP_HIDE_FROM_ABI ldiv_t div(long __x, long __y) _NOEXCEPT { return ::ldiv(__x, __y); }
+# if !(defined(__FreeBSD__) && !defined(__LONG_LONG_SUPPORTED))
+inline _LIBCPP_HIDE_FROM_ABI lldiv_t div(long long __x, long long __y) _NOEXCEPT { return ::lldiv(__x, __y); }
+# endif
+# endif // _LIBCPP_MSVCRT
+} // extern "C++"
+# endif // __cplusplus
+
+#endif // _LIBCPP_STDLIB_H
diff --git a/libcxx/include/__cxx03/stop_token b/libcxx/include/__cxx03/stop_token
new file mode 100644
index 00000000000000..d4e651d9541f4e
--- /dev/null
+++ b/libcxx/include/__cxx03/stop_token
@@ -0,0 +1,56 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STOP_TOKEN
+#define _LIBCPP_STOP_TOKEN
+
+/*
+
+namespace std {
+ // [stoptoken], class stop_token
+ class stop_token;
+
+ // [stopsource], class stop_source
+ class stop_source;
+
+ // no-shared-stop-state indicator
+ struct nostopstate_t {
+ explicit nostopstate_t() = default;
+ };
+ inline constexpr nostopstate_t nostopstate{};
+
+ // [stopcallback], class template stop_callback
+ template<class Callback>
+ class stop_callback;
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+# if _LIBCPP_STD_VER >= 20
+# include <__stop_token/stop_callback.h>
+# include <__stop_token/stop_source.h>
+# include <__stop_token/stop_token.h>
+# endif
+
+# include <version>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+#endif // !defined(_LIBCPP_HAS_NO_THREADS)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <iosfwd>
+#endif
+
+#endif // _LIBCPP_STOP_TOKEN
diff --git a/libcxx/include/__cxx03/streambuf b/libcxx/include/__cxx03/streambuf
new file mode 100644
index 00000000000000..5a3c17ef7c99e7
--- /dev/null
+++ b/libcxx/include/__cxx03/streambuf
@@ -0,0 +1,445 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STREAMBUF
+#define _LIBCPP_STREAMBUF
+
+/*
+ streambuf synopsis
+
+namespace std
+{
+
+template <class charT, class traits = char_traits<charT> >
+class basic_streambuf
+{
+public:
+ // types:
+ typedef charT char_type;
+ typedef traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ virtual ~basic_streambuf();
+
+ // 27.6.2.2.1 locales:
+ locale pubimbue(const locale& loc);
+ locale getloc() const;
+
+ // 27.6.2.2.2 buffer and positioning:
+ basic_streambuf* pubsetbuf(char_type* s, streamsize n);
+ pos_type pubseekoff(off_type off, ios_base::seekdir way,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ pos_type pubseekpos(pos_type sp,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ int pubsync();
+
+ // Get and put areas:
+ // 27.6.2.2.3 Get area:
+ streamsize in_avail();
+ int_type snextc();
+ int_type sbumpc();
+ int_type sgetc();
+ streamsize sgetn(char_type* s, streamsize n);
+
+ // 27.6.2.2.4 Putback:
+ int_type sputbackc(char_type c);
+ int_type sungetc();
+
+ // 27.6.2.2.5 Put area:
+ int_type sputc(char_type c);
+ streamsize sputn(const char_type* s, streamsize n);
+
+protected:
+ basic_streambuf();
+ basic_streambuf(const basic_streambuf& rhs);
+ basic_streambuf& operator=(const basic_streambuf& rhs);
+ void swap(basic_streambuf& rhs);
+
+ // 27.6.2.3.2 Get area:
+ char_type* eback() const;
+ char_type* gptr() const;
+ char_type* egptr() const;
+ void gbump(int n);
+ void setg(char_type* gbeg, char_type* gnext, char_type* gend);
+
+ // 27.6.2.3.3 Put area:
+ char_type* pbase() const;
+ char_type* pptr() const;
+ char_type* epptr() const;
+ void pbump(int n);
+ void setp(char_type* pbeg, char_type* pend);
+
+ // 27.6.2.4 virtual functions:
+ // 27.6.2.4.1 Locales:
+ virtual void imbue(const locale& loc);
+
+ // 27.6.2.4.2 Buffer management and positioning:
+ virtual basic_streambuf* setbuf(char_type* s, streamsize n);
+ virtual pos_type seekoff(off_type off, ios_base::seekdir way,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ virtual pos_type seekpos(pos_type sp,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ virtual int sync();
+
+ // 27.6.2.4.3 Get area:
+ virtual streamsize showmanyc();
+ virtual streamsize xsgetn(char_type* s, streamsize n);
+ virtual int_type underflow();
+ virtual int_type uflow();
+
+ // 27.6.2.4.4 Putback:
+ virtual int_type pbackfail(int_type c = traits_type::eof());
+
+ // 27.6.2.4.5 Put area:
+ virtual streamsize xsputn(const char_type* s, streamsize n);
+ virtual int_type overflow (int_type c = traits_type::eof());
+};
+
+} // std
+
+*/
+
+#include <__assert>
+#include <__config>
+#include <__fwd/streambuf.h>
+#include <__locale>
+#include <__type_traits/is_same.h>
+#include <__utility/is_valid_range.h>
+#include <climits>
+#include <ios>
+#include <iosfwd>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _CharT, class _Traits>
+class _LIBCPP_TEMPLATE_VIS basic_streambuf {
+public:
+ // types:
+ typedef _CharT char_type;
+ typedef _Traits traits_type;
+ typedef typename traits_type::int_type int_type;
+ typedef typename traits_type::pos_type pos_type;
+ typedef typename traits_type::off_type off_type;
+
+ static_assert(is_same<_CharT, typename traits_type::char_type>::value,
+ "traits_type::char_type must be the same type as CharT");
+
+ virtual ~basic_streambuf();
+
+ // 27.6.2.2.1 locales:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 locale pubimbue(const locale& __loc) {
+ imbue(__loc);
+ locale __r = __loc_;
+ __loc_ = __loc;
+ return __r;
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 locale getloc() const { return __loc_; }
+
+ // 27.6.2.2.2 buffer and positioning:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_streambuf* pubsetbuf(char_type* __s, streamsize __n) {
+ return setbuf(__s, __n);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 pos_type
+ pubseekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __which = ios_base::in | ios_base::out) {
+ return seekoff(__off, __way, __which);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 pos_type
+ pubseekpos(pos_type __sp, ios_base::openmode __which = ios_base::in | ios_base::out) {
+ return seekpos(__sp, __which);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int pubsync() { return sync(); }
+
+ // Get and put areas:
+ // 27.6.2.2.3 Get area:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize in_avail() {
+ if (__ninp_ < __einp_)
+ return static_cast<streamsize>(__einp_ - __ninp_);
+ return showmanyc();
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type snextc() {
+ if (sbumpc() == traits_type::eof())
+ return traits_type::eof();
+ return sgetc();
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sbumpc() {
+ if (__ninp_ == __einp_)
+ return uflow();
+ return traits_type::to_int_type(*__ninp_++);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sgetc() {
+ if (__ninp_ == __einp_)
+ return underflow();
+ return traits_type::to_int_type(*__ninp_);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize sgetn(char_type* __s, streamsize __n) { return xsgetn(__s, __n); }
+
+ // 27.6.2.2.4 Putback:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sputbackc(char_type __c) {
+ if (__binp_ == __ninp_ || !traits_type::eq(__c, __ninp_[-1]))
+ return pbackfail(traits_type::to_int_type(__c));
+ return traits_type::to_int_type(*--__ninp_);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sungetc() {
+ if (__binp_ == __ninp_)
+ return pbackfail();
+ return traits_type::to_int_type(*--__ninp_);
+ }
+
+ // 27.6.2.2.5 Put area:
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sputc(char_type __c) {
+ if (__nout_ == __eout_)
+ return overflow(traits_type::to_int_type(__c));
+ *__nout_++ = __c;
+ return traits_type::to_int_type(__c);
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize sputn(const char_type* __s, streamsize __n) {
+ return xsputn(__s, __n);
+ }
+
+protected:
+ basic_streambuf();
+ basic_streambuf(const basic_streambuf& __rhs);
+ basic_streambuf& operator=(const basic_streambuf& __rhs);
+ void swap(basic_streambuf& __rhs);
+
+ // 27.6.2.3.2 Get area:
+ _LIBCPP_HIDE_FROM_ABI char_type* eback() const { return __binp_; }
+ _LIBCPP_HIDE_FROM_ABI char_type* gptr() const { return __ninp_; }
+ _LIBCPP_HIDE_FROM_ABI char_type* egptr() const { return __einp_; }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void gbump(int __n) { __ninp_ += __n; }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void setg(char_type* __gbeg, char_type* __gnext, char_type* __gend) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__gbeg, __gnext), "[gbeg, gnext) must be a valid range");
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__gbeg, __gend), "[gbeg, gend) must be a valid range");
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__gnext, __gend), "[gnext, gend) must be a valid range");
+ __binp_ = __gbeg;
+ __ninp_ = __gnext;
+ __einp_ = __gend;
+ }
+
+ // 27.6.2.3.3 Put area:
+ _LIBCPP_HIDE_FROM_ABI char_type* pbase() const { return __bout_; }
+ _LIBCPP_HIDE_FROM_ABI char_type* pptr() const { return __nout_; }
+ _LIBCPP_HIDE_FROM_ABI char_type* epptr() const { return __eout_; }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void pbump(int __n) { __nout_ += __n; }
+
+ _LIBCPP_HIDE_FROM_ABI void __pbump(streamsize __n) { __nout_ += __n; }
+
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void setp(char_type* __pbeg, char_type* __pend) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__pbeg, __pend), "[pbeg, pend) must be a valid range");
+ __bout_ = __nout_ = __pbeg;
+ __eout_ = __pend;
+ }
+
+ // 27.6.2.4 virtual functions:
+ // 27.6.2.4.1 Locales:
+ virtual void imbue(const locale& __loc);
+
+ // 27.6.2.4.2 Buffer management and positioning:
+ virtual basic_streambuf* setbuf(char_type* __s, streamsize __n);
+ virtual pos_type
+ seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __which = ios_base::in | ios_base::out);
+ virtual pos_type seekpos(pos_type __sp, ios_base::openmode __which = ios_base::in | ios_base::out);
+ virtual int sync();
+
+ // 27.6.2.4.3 Get area:
+ virtual streamsize showmanyc();
+ virtual streamsize xsgetn(char_type* __s, streamsize __n);
+ virtual int_type underflow();
+ virtual int_type uflow();
+
+ // 27.6.2.4.4 Putback:
+ virtual int_type pbackfail(int_type __c = traits_type::eof());
+
+ // 27.6.2.4.5 Put area:
+ virtual streamsize xsputn(const char_type* __s, streamsize __n);
+ virtual int_type overflow(int_type __c = traits_type::eof());
+
+private:
+ locale __loc_;
+ char_type* __binp_;
+ char_type* __ninp_;
+ char_type* __einp_;
+ char_type* __bout_;
+ char_type* __nout_;
+ char_type* __eout_;
+};
+
+template <class _CharT, class _Traits>
+basic_streambuf<_CharT, _Traits>::~basic_streambuf() {}
+
+template <class _CharT, class _Traits>
+basic_streambuf<_CharT, _Traits>::basic_streambuf()
+ : __binp_(nullptr), __ninp_(nullptr), __einp_(nullptr), __bout_(nullptr), __nout_(nullptr), __eout_(nullptr) {}
+
+template <class _CharT, class _Traits>
+basic_streambuf<_CharT, _Traits>::basic_streambuf(const basic_streambuf& __sb)
+ : __loc_(__sb.__loc_),
+ __binp_(__sb.__binp_),
+ __ninp_(__sb.__ninp_),
+ __einp_(__sb.__einp_),
+ __bout_(__sb.__bout_),
+ __nout_(__sb.__nout_),
+ __eout_(__sb.__eout_) {}
+
+template <class _CharT, class _Traits>
+basic_streambuf<_CharT, _Traits>& basic_streambuf<_CharT, _Traits>::operator=(const basic_streambuf& __sb) {
+ __loc_ = __sb.__loc_;
+ __binp_ = __sb.__binp_;
+ __ninp_ = __sb.__ninp_;
+ __einp_ = __sb.__einp_;
+ __bout_ = __sb.__bout_;
+ __nout_ = __sb.__nout_;
+ __eout_ = __sb.__eout_;
+ return *this;
+}
+
+template <class _CharT, class _Traits>
+void basic_streambuf<_CharT, _Traits>::swap(basic_streambuf& __sb) {
+ std::swap(__loc_, __sb.__loc_);
+ std::swap(__binp_, __sb.__binp_);
+ std::swap(__ninp_, __sb.__ninp_);
+ std::swap(__einp_, __sb.__einp_);
+ std::swap(__bout_, __sb.__bout_);
+ std::swap(__nout_, __sb.__nout_);
+ std::swap(__eout_, __sb.__eout_);
+}
+
+template <class _CharT, class _Traits>
+void basic_streambuf<_CharT, _Traits>::imbue(const locale&) {}
+
+template <class _CharT, class _Traits>
+basic_streambuf<_CharT, _Traits>* basic_streambuf<_CharT, _Traits>::setbuf(char_type*, streamsize) {
+ return this;
+}
+
+template <class _CharT, class _Traits>
+typename basic_streambuf<_CharT, _Traits>::pos_type
+basic_streambuf<_CharT, _Traits>::seekoff(off_type, ios_base::seekdir, ios_base::openmode) {
+ return pos_type(off_type(-1));
+}
+
+template <class _CharT, class _Traits>
+typename basic_streambuf<_CharT, _Traits>::pos_type
+basic_streambuf<_CharT, _Traits>::seekpos(pos_type, ios_base::openmode) {
+ return pos_type(off_type(-1));
+}
+
+template <class _CharT, class _Traits>
+int basic_streambuf<_CharT, _Traits>::sync() {
+ return 0;
+}
+
+template <class _CharT, class _Traits>
+streamsize basic_streambuf<_CharT, _Traits>::showmanyc() {
+ return 0;
+}
+
+template <class _CharT, class _Traits>
+streamsize basic_streambuf<_CharT, _Traits>::xsgetn(char_type* __s, streamsize __n) {
+ const int_type __eof = traits_type::eof();
+ int_type __c;
+ streamsize __i = 0;
+ while (__i < __n) {
+ if (__ninp_ < __einp_) {
+ const streamsize __len = std::min(static_cast<streamsize>(INT_MAX), std::min(__einp_ - __ninp_, __n - __i));
+ traits_type::copy(__s, __ninp_, __len);
+ __s += __len;
+ __i += __len;
+ this->gbump(__len);
+ } else if ((__c = uflow()) != __eof) {
+ *__s = traits_type::to_char_type(__c);
+ ++__s;
+ ++__i;
+ } else
+ break;
+ }
+ return __i;
+}
+
+template <class _CharT, class _Traits>
+typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::underflow() {
+ return traits_type::eof();
+}
+
+template <class _CharT, class _Traits>
+typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::uflow() {
+ if (underflow() == traits_type::eof())
+ return traits_type::eof();
+ return traits_type::to_int_type(*__ninp_++);
+}
+
+template <class _CharT, class _Traits>
+typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::pbackfail(int_type) {
+ return traits_type::eof();
+}
+
+template <class _CharT, class _Traits>
+streamsize basic_streambuf<_CharT, _Traits>::xsputn(const char_type* __s, streamsize __n) {
+ streamsize __i = 0;
+ int_type __eof = traits_type::eof();
+ while (__i < __n) {
+ if (__nout_ >= __eout_) {
+ if (overflow(traits_type::to_int_type(*__s)) == __eof)
+ break;
+ ++__s;
+ ++__i;
+ } else {
+ streamsize __chunk_size = std::min(__eout_ - __nout_, __n - __i);
+ traits_type::copy(__nout_, __s, __chunk_size);
+ __nout_ += __chunk_size;
+ __s += __chunk_size;
+ __i += __chunk_size;
+ }
+ }
+ return __i;
+}
+
+template <class _CharT, class _Traits>
+typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::overflow(int_type) {
+ return traits_type::eof();
+}
+
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_streambuf<char>;
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_streambuf<wchar_t>;
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdint>
+#endif
+
+#endif // _LIBCPP_STREAMBUF
diff --git a/libcxx/include/__cxx03/string b/libcxx/include/__cxx03/string
new file mode 100644
index 00000000000000..9fa979e3a5178a
--- /dev/null
+++ b/libcxx/include/__cxx03/string
@@ -0,0 +1,4352 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STRING
+#define _LIBCPP_STRING
+
+// clang-format off
+
+/*
+ string synopsis
+
+#include <compare>
+#include <initializer_list>
+
+namespace std
+{
+
+template <class stateT>
+class fpos
+{
+private:
+ stateT st;
+public:
+ fpos(streamoff = streamoff());
+
+ operator streamoff() const;
+
+ stateT state() const;
+ void state(stateT);
+
+ fpos& operator+=(streamoff);
+ fpos operator+ (streamoff) const;
+ fpos& operator-=(streamoff);
+ fpos operator- (streamoff) const;
+};
+
+template <class stateT> streamoff operator-(const fpos<stateT>& x, const fpos<stateT>& y);
+
+template <class stateT> bool operator==(const fpos<stateT>& x, const fpos<stateT>& y);
+template <class stateT> bool operator!=(const fpos<stateT>& x, const fpos<stateT>& y);
+
+template <class charT>
+struct char_traits
+{
+ using char_type = charT;
+ using int_type = ...;
+ using off_type = streamoff;
+ using pos_type = streampos;
+ using state_type = mbstate_t;
+ using comparison_category = strong_ordering; // Since C++20 only for the specializations
+ // char, wchar_t, char8_t, char16_t, and char32_t.
+
+ static void assign(char_type& c1, const char_type& c2) noexcept;
+ static constexpr bool eq(char_type c1, char_type c2) noexcept;
+ static constexpr bool lt(char_type c1, char_type c2) noexcept;
+
+ static int compare(const char_type* s1, const char_type* s2, size_t n);
+ static size_t length(const char_type* s);
+ static const char_type* find(const char_type* s, size_t n, const char_type& a);
+ static char_type* move(char_type* s1, const char_type* s2, size_t n);
+ static char_type* copy(char_type* s1, const char_type* s2, size_t n);
+ static char_type* assign(char_type* s, size_t n, char_type a);
+
+ static constexpr int_type not_eof(int_type c) noexcept;
+ static constexpr char_type to_char_type(int_type c) noexcept;
+ static constexpr int_type to_int_type(char_type c) noexcept;
+ static constexpr bool eq_int_type(int_type c1, int_type c2) noexcept;
+ static constexpr int_type eof() noexcept;
+};
+
+template <> struct char_traits<char>;
+template <> struct char_traits<wchar_t>;
+template <> struct char_traits<char8_t>; // C++20
+template <> struct char_traits<char16_t>;
+template <> struct char_traits<char32_t>;
+
+template<class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
+class basic_string
+{
+public:
+// types:
+ typedef traits traits_type;
+ typedef typename traits_type::char_type value_type;
+ typedef Allocator allocator_type;
+ typedef typename allocator_type::size_type size_type;
+ typedef typename allocator_type::difference_type difference_type;
+ typedef typename allocator_type::reference reference;
+ typedef typename allocator_type::const_reference const_reference;
+ typedef typename allocator_type::pointer pointer;
+ typedef typename allocator_type::const_pointer const_pointer;
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+ static const size_type npos = -1;
+
+ basic_string()
+ noexcept(is_nothrow_default_constructible<allocator_type>::value); // constexpr since C++20
+ explicit basic_string(const allocator_type& a); // constexpr since C++20
+ basic_string(const basic_string& str); // constexpr since C++20
+ basic_string(basic_string&& str)
+ noexcept(is_nothrow_move_constructible<allocator_type>::value); // constexpr since C++20
+ basic_string(const basic_string& str, size_type pos,
+ const allocator_type& a = allocator_type()); // constexpr since C++20
+ basic_string(const basic_string& str, size_type pos, size_type n,
+ const Allocator& a = Allocator()); // constexpr since C++20
+ constexpr basic_string(
+ basic_string&& str, size_type pos, const Allocator& a = Allocator()); // since C++23
+ constexpr basic_string(
+ basic_string&& str, size_type pos, size_type n, const Allocator& a = Allocator()); // since C++23
+ template<class T>
+ basic_string(const T& t, size_type pos, size_type n, const Allocator& a = Allocator()); // C++17, constexpr since C++20
+ template <class T>
+ explicit basic_string(const T& t, const Allocator& a = Allocator()); // C++17, constexpr since C++20
+ basic_string(const value_type* s, const allocator_type& a = allocator_type()); // constexpr since C++20
+ basic_string(const value_type* s, size_type n, const allocator_type& a = allocator_type()); // constexpr since C++20
+ basic_string(nullptr_t) = delete; // C++23
+ basic_string(size_type n, value_type c, const allocator_type& a = allocator_type()); // constexpr since C++20
+ template<class InputIterator>
+ basic_string(InputIterator begin, InputIterator end,
+ const allocator_type& a = allocator_type()); // constexpr since C++20
+ template<container-compatible-range<charT> R>
+ constexpr basic_string(from_range_t, R&& rg, const Allocator& a = Allocator()); // since C++23
+ basic_string(initializer_list<value_type>, const Allocator& = Allocator()); // constexpr since C++20
+ basic_string(const basic_string&, const Allocator&); // constexpr since C++20
+ basic_string(basic_string&&, const Allocator&); // constexpr since C++20
+
+ ~basic_string(); // constexpr since C++20
+
+ operator basic_string_view<charT, traits>() const noexcept; // constexpr since C++20
+
+ basic_string& operator=(const basic_string& str); // constexpr since C++20
+ template <class T>
+ basic_string& operator=(const T& t); // C++17, constexpr since C++20
+ basic_string& operator=(basic_string&& str)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value ||
+ allocator_type::is_always_equal::value ); // C++17, constexpr since C++20
+ basic_string& operator=(const value_type* s); // constexpr since C++20
+ basic_string& operator=(nullptr_t) = delete; // C++23
+ basic_string& operator=(value_type c); // constexpr since C++20
+ basic_string& operator=(initializer_list<value_type>); // constexpr since C++20
+
+ iterator begin() noexcept; // constexpr since C++20
+ const_iterator begin() const noexcept; // constexpr since C++20
+ iterator end() noexcept; // constexpr since C++20
+ const_iterator end() const noexcept; // constexpr since C++20
+
+ reverse_iterator rbegin() noexcept; // constexpr since C++20
+ const_reverse_iterator rbegin() const noexcept; // constexpr since C++20
+ reverse_iterator rend() noexcept; // constexpr since C++20
+ const_reverse_iterator rend() const noexcept; // constexpr since C++20
+
+ const_iterator cbegin() const noexcept; // constexpr since C++20
+ const_iterator cend() const noexcept; // constexpr since C++20
+ const_reverse_iterator crbegin() const noexcept; // constexpr since C++20
+ const_reverse_iterator crend() const noexcept; // constexpr since C++20
+
+ size_type size() const noexcept; // constexpr since C++20
+ size_type length() const noexcept; // constexpr since C++20
+ size_type max_size() const noexcept; // constexpr since C++20
+ size_type capacity() const noexcept; // constexpr since C++20
+
+ void resize(size_type n, value_type c); // constexpr since C++20
+ void resize(size_type n); // constexpr since C++20
+
+ template<class Operation>
+ constexpr void resize_and_overwrite(size_type n, Operation op); // since C++23
+
+ void reserve(size_type res_arg); // constexpr since C++20
+ void reserve(); // deprecated in C++20, removed in C++26
+ void shrink_to_fit(); // constexpr since C++20
+ void clear() noexcept; // constexpr since C++20
+ bool empty() const noexcept; // constexpr since C++20
+
+ const_reference operator[](size_type pos) const; // constexpr since C++20
+ reference operator[](size_type pos); // constexpr since C++20
+
+ const_reference at(size_type n) const; // constexpr since C++20
+ reference at(size_type n); // constexpr since C++20
+
+ basic_string& operator+=(const basic_string& str); // constexpr since C++20
+ template <class T>
+ basic_string& operator+=(const T& t); // C++17, constexpr since C++20
+ basic_string& operator+=(const value_type* s); // constexpr since C++20
+ basic_string& operator+=(value_type c); // constexpr since C++20
+ basic_string& operator+=(initializer_list<value_type>); // constexpr since C++20
+
+ basic_string& append(const basic_string& str); // constexpr since C++20
+ template <class T>
+ basic_string& append(const T& t); // C++17, constexpr since C++20
+ basic_string& append(const basic_string& str, size_type pos, size_type n=npos); // C++14, constexpr since C++20
+ template <class T>
+ basic_string& append(const T& t, size_type pos, size_type n=npos); // C++17, constexpr since C++20
+ basic_string& append(const value_type* s, size_type n); // constexpr since C++20
+ basic_string& append(const value_type* s); // constexpr since C++20
+ basic_string& append(size_type n, value_type c); // constexpr since C++20
+ template<class InputIterator>
+ basic_string& append(InputIterator first, InputIterator last); // constexpr since C++20
+ template<container-compatible-range<charT> R>
+ constexpr basic_string& append_range(R&& rg); // C++23
+ basic_string& append(initializer_list<value_type>); // constexpr since C++20
+
+ void push_back(value_type c); // constexpr since C++20
+ void pop_back(); // constexpr since C++20
+ reference front(); // constexpr since C++20
+ const_reference front() const; // constexpr since C++20
+ reference back(); // constexpr since C++20
+ const_reference back() const; // constexpr since C++20
+
+ basic_string& assign(const basic_string& str); // constexpr since C++20
+ template <class T>
+ basic_string& assign(const T& t); // C++17, constexpr since C++20
+ basic_string& assign(basic_string&& str); // constexpr since C++20
+ basic_string& assign(const basic_string& str, size_type pos, size_type n=npos); // C++14, constexpr since C++20
+ template <class T>
+ basic_string& assign(const T& t, size_type pos, size_type n=npos); // C++17, constexpr since C++20
+ basic_string& assign(const value_type* s, size_type n); // constexpr since C++20
+ basic_string& assign(const value_type* s); // constexpr since C++20
+ basic_string& assign(size_type n, value_type c); // constexpr since C++20
+ template<class InputIterator>
+ basic_string& assign(InputIterator first, InputIterator last); // constexpr since C++20
+ template<container-compatible-range<charT> R>
+ constexpr basic_string& assign_range(R&& rg); // C++23
+ basic_string& assign(initializer_list<value_type>); // constexpr since C++20
+
+ basic_string& insert(size_type pos1, const basic_string& str); // constexpr since C++20
+ template <class T>
+ basic_string& insert(size_type pos1, const T& t); // constexpr since C++20
+ basic_string& insert(size_type pos1, const basic_string& str,
+ size_type pos2, size_type n); // constexpr since C++20
+ template <class T>
+ basic_string& insert(size_type pos1, const T& t, size_type pos2, size_type n); // C++17, constexpr since C++20
+ basic_string& insert(size_type pos, const value_type* s, size_type n=npos); // C++14, constexpr since C++20
+ basic_string& insert(size_type pos, const value_type* s); // constexpr since C++20
+ basic_string& insert(size_type pos, size_type n, value_type c); // constexpr since C++20
+ iterator insert(const_iterator p, value_type c); // constexpr since C++20
+ iterator insert(const_iterator p, size_type n, value_type c); // constexpr since C++20
+ template<class InputIterator>
+ iterator insert(const_iterator p, InputIterator first, InputIterator last); // constexpr since C++20
+ template<container-compatible-range<charT> R>
+ constexpr iterator insert_range(const_iterator p, R&& rg); // C++23
+ iterator insert(const_iterator p, initializer_list<value_type>); // constexpr since C++20
+
+ basic_string& erase(size_type pos = 0, size_type n = npos); // constexpr since C++20
+ iterator erase(const_iterator position); // constexpr since C++20
+ iterator erase(const_iterator first, const_iterator last); // constexpr since C++20
+
+ basic_string& replace(size_type pos1, size_type n1, const basic_string& str); // constexpr since C++20
+ template <class T>
+ basic_string& replace(size_type pos1, size_type n1, const T& t); // C++17, constexpr since C++20
+ basic_string& replace(size_type pos1, size_type n1, const basic_string& str,
+ size_type pos2, size_type n2=npos); // C++14, constexpr since C++20
+ template <class T>
+ basic_string& replace(size_type pos1, size_type n1, const T& t,
+ size_type pos2, size_type n); // C++17, constexpr since C++20
+ basic_string& replace(size_type pos, size_type n1, const value_type* s, size_type n2); // constexpr since C++20
+ basic_string& replace(size_type pos, size_type n1, const value_type* s); // constexpr since C++20
+ basic_string& replace(size_type pos, size_type n1, size_type n2, value_type c); // constexpr since C++20
+ basic_string& replace(const_iterator i1, const_iterator i2, const basic_string& str); // constexpr since C++20
+ template <class T>
+ basic_string& replace(const_iterator i1, const_iterator i2, const T& t); // C++17, constexpr since C++20
+ basic_string& replace(const_iterator i1, const_iterator i2, const value_type* s, size_type n); // constexpr since C++20
+ basic_string& replace(const_iterator i1, const_iterator i2, const value_type* s); // constexpr since C++20
+ basic_string& replace(const_iterator i1, const_iterator i2, size_type n, value_type c); // constexpr since C++20
+ template<class InputIterator>
+ basic_string& replace(const_iterator i1, const_iterator i2, InputIterator j1, InputIterator j2); // constexpr since C++20
+ template<container-compatible-range<charT> R>
+ constexpr basic_string& replace_with_range(const_iterator i1, const_iterator i2, R&& rg); // C++23
+ basic_string& replace(const_iterator i1, const_iterator i2, initializer_list<value_type>); // constexpr since C++20
+
+ size_type copy(value_type* s, size_type n, size_type pos = 0) const; // constexpr since C++20
+ basic_string substr(size_type pos = 0, size_type n = npos) const; // constexpr in C++20, removed in C++23
+ basic_string substr(size_type pos = 0, size_type n = npos) const&; // since C++23
+ constexpr basic_string substr(size_type pos = 0, size_type n = npos) &&; // since C++23
+ void swap(basic_string& str)
+ noexcept(allocator_traits<allocator_type>::propagate_on_container_swap::value ||
+ allocator_traits<allocator_type>::is_always_equal::value); // C++17, constexpr since C++20
+
+ const value_type* c_str() const noexcept; // constexpr since C++20
+ const value_type* data() const noexcept; // constexpr since C++20
+ value_type* data() noexcept; // C++17, constexpr since C++20
+
+ allocator_type get_allocator() const noexcept; // constexpr since C++20
+
+ size_type find(const basic_string& str, size_type pos = 0) const noexcept; // constexpr since C++20
+ template <class T>
+ size_type find(const T& t, size_type pos = 0) const noexcept; // C++17, noexcept as an extension, constexpr since C++20
+ size_type find(const value_type* s, size_type pos, size_type n) const noexcept; // constexpr since C++20
+ size_type find(const value_type* s, size_type pos = 0) const noexcept; // constexpr since C++20
+ size_type find(value_type c, size_type pos = 0) const noexcept; // constexpr since C++20
+
+ size_type rfind(const basic_string& str, size_type pos = npos) const noexcept; // constexpr since C++20
+ template <class T>
+ size_type rfind(const T& t, size_type pos = npos) const noexcept; // C++17, noexcept as an extension, constexpr since C++20
+ size_type rfind(const value_type* s, size_type pos, size_type n) const noexcept; // constexpr since C++20
+ size_type rfind(const value_type* s, size_type pos = npos) const noexcept; // constexpr since C++20
+ size_type rfind(value_type c, size_type pos = npos) const noexcept; // constexpr since C++20
+
+ size_type find_first_of(const basic_string& str, size_type pos = 0) const noexcept; // constexpr since C++20
+ template <class T>
+ size_type find_first_of(const T& t, size_type pos = 0) const noexcept; // C++17, noexcept as an extension, constexpr since C++20
+ size_type find_first_of(const value_type* s, size_type pos, size_type n) const noexcept; // constexpr since C++20
+ size_type find_first_of(const value_type* s, size_type pos = 0) const noexcept; // constexpr since C++20
+ size_type find_first_of(value_type c, size_type pos = 0) const noexcept; // constexpr since C++20
+
+ size_type find_last_of(const basic_string& str, size_type pos = npos) const noexcept; // constexpr since C++20
+ template <class T>
+ size_type find_last_of(const T& t, size_type pos = npos) const noexcept noexcept; // C++17, noexcept as an extension, constexpr since C++20
+ size_type find_last_of(const value_type* s, size_type pos, size_type n) const noexcept; // constexpr since C++20
+ size_type find_last_of(const value_type* s, size_type pos = npos) const noexcept; // constexpr since C++20
+ size_type find_last_of(value_type c, size_type pos = npos) const noexcept; // constexpr since C++20
+
+ size_type find_first_not_of(const basic_string& str, size_type pos = 0) const noexcept; // constexpr since C++20
+ template <class T>
+ size_type find_first_not_of(const T& t, size_type pos = 0) const noexcept; // C++17, noexcept as an extension, constexpr since C++20
+ size_type find_first_not_of(const value_type* s, size_type pos, size_type n) const noexcept; // constexpr since C++20
+ size_type find_first_not_of(const value_type* s, size_type pos = 0) const noexcept; // constexpr since C++20
+ size_type find_first_not_of(value_type c, size_type pos = 0) const noexcept; // constexpr since C++20
+
+ size_type find_last_not_of(const basic_string& str, size_type pos = npos) const noexcept; // constexpr since C++20
+ template <class T>
+ size_type find_last_not_of(const T& t, size_type pos = npos) const noexcept; // C++17, noexcept as an extension, constexpr since C++20
+ size_type find_last_not_of(const value_type* s, size_type pos, size_type n) const noexcept; // constexpr since C++20
+ size_type find_last_not_of(const value_type* s, size_type pos = npos) const noexcept; // constexpr since C++20
+ size_type find_last_not_of(value_type c, size_type pos = npos) const noexcept; // constexpr since C++20
+
+ int compare(const basic_string& str) const noexcept; // constexpr since C++20
+ template <class T>
+ int compare(const T& t) const noexcept; // C++17, noexcept as an extension, constexpr since C++20
+ int compare(size_type pos1, size_type n1, const basic_string& str) const; // constexpr since C++20
+ template <class T>
+ int compare(size_type pos1, size_type n1, const T& t) const; // C++17, constexpr since C++20
+ int compare(size_type pos1, size_type n1, const basic_string& str,
+ size_type pos2, size_type n2=npos) const; // C++14, constexpr since C++20
+ template <class T>
+ int compare(size_type pos1, size_type n1, const T& t,
+ size_type pos2, size_type n2=npos) const; // C++17, constexpr since C++20
+ int compare(const value_type* s) const noexcept; // constexpr since C++20
+ int compare(size_type pos1, size_type n1, const value_type* s) const; // constexpr since C++20
+ int compare(size_type pos1, size_type n1, const value_type* s, size_type n2) const; // constexpr since C++20
+
+ constexpr bool starts_with(basic_string_view<charT, traits> sv) const noexcept; // C++20
+ constexpr bool starts_with(charT c) const noexcept; // C++20
+ constexpr bool starts_with(const charT* s) const; // C++20
+ constexpr bool ends_with(basic_string_view<charT, traits> sv) const noexcept; // C++20
+ constexpr bool ends_with(charT c) const noexcept; // C++20
+ constexpr bool ends_with(const charT* s) const; // C++20
+
+ constexpr bool contains(basic_string_view<charT, traits> sv) const noexcept; // C++23
+ constexpr bool contains(charT c) const noexcept; // C++23
+ constexpr bool contains(const charT* s) const; // C++23
+};
+
+template<class InputIterator,
+ class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+basic_string(InputIterator, InputIterator, Allocator = Allocator())
+ -> basic_string<typename iterator_traits<InputIterator>::value_type,
+ char_traits<typename iterator_traits<InputIterator>::value_type>,
+ Allocator>; // C++17
+
+template<ranges::input_range R,
+ class Allocator = allocator<ranges::range_value_t<R>>>
+ basic_string(from_range_t, R&&, Allocator = Allocator())
+ -> basic_string<ranges::range_value_t<R>, char_traits<ranges::range_value_t<R>>,
+ Allocator>; // C++23
+
+template<class charT,
+ class traits,
+ class Allocator = allocator<charT>>
+ explicit basic_string(basic_string_view<charT, traits>, const Allocator& = Allocator())
+ -> basic_string<charT, traits, Allocator>; // C++17
+
+template<class charT,
+ class traits,
+ class Allocator = allocator<charT>>
+ basic_string(basic_string_view<charT, traits>,
+ typename see below::size_type, typename see below::size_type,
+ const Allocator& = Allocator())
+ -> basic_string<charT, traits, Allocator>; // C++17
+
+template<class charT, class traits, class Allocator>
+basic_string<charT, traits, Allocator>
+operator+(const basic_string<charT, traits, Allocator>& lhs,
+ const basic_string<charT, traits, Allocator>& rhs); // constexpr since C++20
+
+template<class charT, class traits, class Allocator>
+basic_string<charT, traits, Allocator>
+operator+(const charT* lhs , const basic_string<charT,traits,Allocator>&rhs); // constexpr since C++20
+
+template<class charT, class traits, class Allocator>
+basic_string<charT, traits, Allocator>
+operator+(charT lhs, const basic_string<charT,traits,Allocator>& rhs); // constexpr since C++20
+
+template<class charT, class traits, class Allocator>
+basic_string<charT, traits, Allocator>
+operator+(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs); // constexpr since C++20
+
+template<class charT, class traits, class Allocator>
+basic_string<charT, traits, Allocator>
+operator+(const basic_string<charT, traits, Allocator>& lhs, charT rhs); // constexpr since C++20
+
+template<class charT, class traits, class Allocator>
+ constexpr basic_string<charT, traits, Allocator>
+ operator+(const basic_string<charT, traits, Allocator>& lhs,
+ type_identity_t<basic_string_view<charT, traits>> rhs); // Since C++26
+template<class charT, class traits, class Allocator>
+ constexpr basic_string<charT, traits, Allocator>
+ operator+(basic_string<charT, traits, Allocator>&& lhs,
+ type_identity_t<basic_string_view<charT, traits>> rhs); // Since C++26
+template<class charT, class traits, class Allocator>
+ constexpr basic_string<charT, traits, Allocator>
+ operator+(type_identity_t<basic_string_view<charT, traits>> lhs,
+ const basic_string<charT, traits, Allocator>& rhs); // Since C++26
+template<class charT, class traits, class Allocator>
+ constexpr basic_string<charT, traits, Allocator>
+ operator+(type_identity_t<basic_string_view<charT, traits>> lhs,
+ basic_string<charT, traits, Allocator>&& rhs); // Since C++26
+
+
+template<class charT, class traits, class Allocator>
+bool operator==(const basic_string<charT, traits, Allocator>& lhs,
+ const basic_string<charT, traits, Allocator>& rhs) noexcept; // constexpr since C++20
+
+template<class charT, class traits, class Allocator>
+bool operator==(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator==(const basic_string<charT,traits,Allocator>& lhs, const charT* rhs) noexcept; // constexpr since C++20
+
+template<class charT, class traits, class Allocator>
+bool operator!=(const basic_string<charT,traits,Allocator>& lhs,
+ const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator!=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator!=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator< (const basic_string<charT, traits, Allocator>& lhs,
+ const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator< (const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator< (const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator> (const basic_string<charT, traits, Allocator>& lhs,
+ const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator> (const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator> (const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator<=(const basic_string<charT, traits, Allocator>& lhs,
+ const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator<=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator<=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator>=(const basic_string<charT, traits, Allocator>& lhs,
+ const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator>=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator>
+bool operator>=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept; // removed in C++20
+
+template<class charT, class traits, class Allocator> // since C++20
+constexpr see below operator<=>(const basic_string<charT, traits, Allocator>& lhs,
+ const basic_string<charT, traits, Allocator>& rhs) noexcept;
+
+template<class charT, class traits, class Allocator> // since C++20
+constexpr see below operator<=>(const basic_string<charT, traits, Allocator>& lhs,
+ const charT* rhs) noexcept;
+
+template<class charT, class traits, class Allocator>
+void swap(basic_string<charT, traits, Allocator>& lhs,
+ basic_string<charT, traits, Allocator>& rhs)
+ noexcept(noexcept(lhs.swap(rhs))); // constexpr since C++20
+
+template<class charT, class traits, class Allocator>
+basic_istream<charT, traits>&
+operator>>(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str);
+
+template<class charT, class traits, class Allocator>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& os, const basic_string<charT, traits, Allocator>& str);
+
+template<class charT, class traits, class Allocator>
+basic_istream<charT, traits>&
+getline(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str,
+ charT delim);
+
+template<class charT, class traits, class Allocator>
+basic_istream<charT, traits>&
+getline(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str);
+
+template<class charT, class traits, class Allocator, class U>
+typename basic_string<charT, traits, Allocator>::size_type
+erase(basic_string<charT, traits, Allocator>& c, const U& value); // C++20
+template<class charT, class traits, class Allocator, class Predicate>
+typename basic_string<charT, traits, Allocator>::size_type
+erase_if(basic_string<charT, traits, Allocator>& c, Predicate pred); // C++20
+
+typedef basic_string<char> string;
+typedef basic_string<wchar_t> wstring;
+typedef basic_string<char8_t> u8string; // C++20
+typedef basic_string<char16_t> u16string;
+typedef basic_string<char32_t> u32string;
+
+int stoi (const string& str, size_t* idx = nullptr, int base = 10);
+long stol (const string& str, size_t* idx = nullptr, int base = 10);
+unsigned long stoul (const string& str, size_t* idx = nullptr, int base = 10);
+long long stoll (const string& str, size_t* idx = nullptr, int base = 10);
+unsigned long long stoull(const string& str, size_t* idx = nullptr, int base = 10);
+
+float stof (const string& str, size_t* idx = nullptr);
+double stod (const string& str, size_t* idx = nullptr);
+long double stold(const string& str, size_t* idx = nullptr);
+
+string to_string(int val);
+string to_string(unsigned val);
+string to_string(long val);
+string to_string(unsigned long val);
+string to_string(long long val);
+string to_string(unsigned long long val);
+string to_string(float val);
+string to_string(double val);
+string to_string(long double val);
+
+int stoi (const wstring& str, size_t* idx = nullptr, int base = 10);
+long stol (const wstring& str, size_t* idx = nullptr, int base = 10);
+unsigned long stoul (const wstring& str, size_t* idx = nullptr, int base = 10);
+long long stoll (const wstring& str, size_t* idx = nullptr, int base = 10);
+unsigned long long stoull(const wstring& str, size_t* idx = nullptr, int base = 10);
+
+float stof (const wstring& str, size_t* idx = nullptr);
+double stod (const wstring& str, size_t* idx = nullptr);
+long double stold(const wstring& str, size_t* idx = nullptr);
+
+wstring to_wstring(int val);
+wstring to_wstring(unsigned val);
+wstring to_wstring(long val);
+wstring to_wstring(unsigned long val);
+wstring to_wstring(long long val);
+wstring to_wstring(unsigned long long val);
+wstring to_wstring(float val);
+wstring to_wstring(double val);
+wstring to_wstring(long double val);
+
+template <> struct hash<string>;
+template <> struct hash<u8string>; // C++20
+template <> struct hash<u16string>;
+template <> struct hash<u32string>;
+template <> struct hash<wstring>;
+
+basic_string<char> operator""s( const char *str, size_t len ); // C++14, constexpr since C++20
+basic_string<wchar_t> operator""s( const wchar_t *str, size_t len ); // C++14, constexpr since C++20
+constexpr basic_string<char8_t> operator""s( const char8_t *str, size_t len ); // C++20
+basic_string<char16_t> operator""s( const char16_t *str, size_t len ); // C++14, constexpr since C++20
+basic_string<char32_t> operator""s( const char32_t *str, size_t len ); // C++14, constexpr since C++20
+
+} // std
+
+*/
+
+// clang-format on
+
+#include <__algorithm/max.h>
+#include <__algorithm/min.h>
+#include <__algorithm/remove.h>
+#include <__algorithm/remove_if.h>
+#include <__assert>
+#include <__config>
+#include <__debug_utils/sanitizers.h>
+#include <__format/enable_insertable.h>
+#include <__functional/hash.h>
+#include <__functional/unary_function.h>
+#include <__fwd/string.h>
+#include <__ios/fpos.h>
+#include <__iterator/bounded_iter.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__iterator/wrap_iter.h>
+#include <__memory/addressof.h>
+#include <__memory/allocate_at_least.h>
+#include <__memory/allocator.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/compressed_pair.h>
+#include <__memory/construct_at.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/swap_allocator.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__ranges/size.h>
+#include <__string/char_traits.h>
+#include <__string/extern_template_lists.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/is_allocator.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_standard_layout.h>
+#include <__type_traits/is_trivial.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/noexcept_move_assign_container.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/void_t.h>
+#include <__utility/auto_cast.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/is_pointer_in_range.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <__utility/unreachable.h>
+#include <climits>
+#include <cstdio> // EOF
+#include <cstring>
+#include <limits>
+#include <stdexcept>
+#include <string_view>
+#include <version>
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+# include <cwchar>
+#endif
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [string.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if !defined(_LIBCPP_HAS_NO_ASAN) && defined(_LIBCPP_INSTRUMENTED_WITH_ASAN)
+# define _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS __attribute__((__no_sanitize__("address")))
+// This macro disables AddressSanitizer (ASan) instrumentation for a specific function,
+// allowing memory accesses that would normally trigger ASan errors to proceed without crashing.
+// This is useful for accessing parts of objects memory, which should not be accessed,
+// such as unused bytes in short strings, that should never be accessed
+// by other parts of the program.
+#else
+# define _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// basic_string
+
+template <class _CharT, class _Traits, class _Allocator>
+basic_string<_CharT, _Traits, _Allocator> _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, const basic_string<_CharT, _Traits, _Allocator>& __y);
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDDEN _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const _CharT* __x, const basic_string<_CharT, _Traits, _Allocator>& __y);
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(_CharT __x, const basic_string<_CharT, _Traits, _Allocator>& __y);
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, const _CharT* __y);
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, _CharT __y);
+
+#if _LIBCPP_STD_VER >= 26
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr basic_string<_CharT, _Traits, _Allocator>
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ type_identity_t<basic_string_view<_CharT, _Traits>> __rhs);
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr basic_string<_CharT, _Traits, _Allocator>
+operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, type_identity_t<basic_string_view<_CharT, _Traits>> __rhs);
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr basic_string<_CharT, _Traits, _Allocator>
+operator+(type_identity_t<basic_string_view<_CharT, _Traits>> __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs);
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr basic_string<_CharT, _Traits, _Allocator>
+operator+(type_identity_t<basic_string_view<_CharT, _Traits>> __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs);
+
+#endif
+
+extern template _LIBCPP_EXPORTED_FROM_ABI string operator+
+ <char, char_traits<char>, allocator<char> >(char const*, string const&);
+
+template <class _Iter>
+struct __string_is_trivial_iterator : public false_type {};
+
+template <class _Tp>
+struct __string_is_trivial_iterator<_Tp*> : public is_arithmetic<_Tp> {};
+
+template <class _Iter>
+struct __string_is_trivial_iterator<__wrap_iter<_Iter> > : public __string_is_trivial_iterator<_Iter> {};
+
+template <class _CharT, class _Traits, class _Tp>
+struct __can_be_converted_to_string_view
+ : public _BoolConstant< is_convertible<const _Tp&, basic_string_view<_CharT, _Traits> >::value &&
+ !is_convertible<const _Tp&, const _CharT*>::value > {};
+
+struct __uninitialized_size_tag {};
+struct __init_with_sentinel_tag {};
+
+template <class _CharT, class _Traits, class _Allocator>
+class basic_string {
+private:
+ using __default_allocator_type = allocator<_CharT>;
+
+public:
+ typedef basic_string __self;
+ typedef basic_string_view<_CharT, _Traits> __self_view;
+ typedef _Traits traits_type;
+ typedef _CharT value_type;
+ typedef _Allocator allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+ typedef typename __alloc_traits::size_type size_type;
+ typedef typename __alloc_traits::difference_type difference_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+
+ // A basic_string contains the following members which may be trivially relocatable:
+ // - pointer: is currently assumed to be trivially relocatable, but is still checked in case that changes
+ // - size_type: is always trivially relocatable, since it has to be an integral type
+ // - value_type: is always trivially relocatable, since it has to be trivial
+ // - unsigned char: is a fundamental type, so it's trivially relocatable
+ // - allocator_type: may or may not be trivially relocatable, so it's checked
+ //
+ // This string implementation doesn't contain any references into itself. It only contains a bit that says whether
+ // it is in small or large string mode, so the entire structure is trivially relocatable if its members are.
+#if !defined(_LIBCPP_HAS_NO_ASAN) && defined(_LIBCPP_INSTRUMENTED_WITH_ASAN)
+ // When compiling with AddressSanitizer (ASan), basic_string cannot be trivially
+ // relocatable. Because the object's memory might be poisoned when its content
+ // is kept inside objects memory (short string optimization), instead of in allocated
+ // external memory. In such cases, the destructor is responsible for unpoisoning
+ // the memory to avoid triggering false positives.
+ // Therefore it's crucial to ensure the destructor is called.
+ using __trivially_relocatable = void;
+#else
+ using __trivially_relocatable = __conditional_t<
+ __libcpp_is_trivially_relocatable<allocator_type>::value && __libcpp_is_trivially_relocatable<pointer>::value,
+ basic_string,
+ void>;
+#endif
+#if !defined(_LIBCPP_HAS_NO_ASAN) && defined(_LIBCPP_INSTRUMENTED_WITH_ASAN)
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pointer __asan_volatile_wrapper(pointer const& __ptr) const {
+ if (__libcpp_is_constant_evaluated())
+ return __ptr;
+
+ pointer volatile __copy_ptr = __ptr;
+
+ return const_cast<pointer&>(__copy_ptr);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_pointer
+ __asan_volatile_wrapper(const_pointer const& __ptr) const {
+ if (__libcpp_is_constant_evaluated())
+ return __ptr;
+
+ const_pointer volatile __copy_ptr = __ptr;
+
+ return const_cast<const_pointer&>(__copy_ptr);
+ }
+# define _LIBCPP_ASAN_VOLATILE_WRAPPER(PTR) __asan_volatile_wrapper(PTR)
+#else
+# define _LIBCPP_ASAN_VOLATILE_WRAPPER(PTR) PTR
+#endif
+
+ static_assert(!is_array<value_type>::value, "Character type of basic_string must not be an array");
+ static_assert(is_standard_layout<value_type>::value, "Character type of basic_string must be standard-layout");
+ static_assert(is_trivial<value_type>::value, "Character type of basic_string must be trivial");
+ static_assert(is_same<_CharT, typename traits_type::char_type>::value,
+ "traits_type::char_type must be the same type as CharT");
+ static_assert(is_same<typename allocator_type::value_type, value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+
+#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS_IN_STRING
+ // Users might provide custom allocators, and prior to C++20 we have no existing way to detect whether the allocator's
+ // pointer type is contiguous (though it has to be by the Standard). Using the wrapper type ensures the iterator is
+ // considered contiguous.
+ typedef __bounded_iter<__wrap_iter<pointer>> iterator;
+ typedef __bounded_iter<__wrap_iter<const_pointer>> const_iterator;
+#else
+ typedef __wrap_iter<pointer> iterator;
+ typedef __wrap_iter<const_pointer> const_iterator;
+#endif
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+private:
+ static_assert(CHAR_BIT == 8, "This implementation assumes that one byte contains 8 bits");
+
+#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+
+ struct __long {
+ pointer __data_;
+ size_type __size_;
+ size_type __cap_ : sizeof(size_type) * CHAR_BIT - 1;
+ size_type __is_long_ : 1;
+ };
+
+ enum { __min_cap = (sizeof(__long) - 1) / sizeof(value_type) > 2 ? (sizeof(__long) - 1) / sizeof(value_type) : 2 };
+
+ struct __short {
+ value_type __data_[__min_cap];
+ unsigned char __padding_[sizeof(value_type) - 1];
+ unsigned char __size_ : 7;
+ unsigned char __is_long_ : 1;
+ };
+
+ // The __endian_factor is required because the field we use to store the size
+ // has one fewer bit than it would if it were not a bitfield.
+ //
+ // If the LSB is used to store the short-flag in the short string representation,
+ // we have to multiply the size by two when it is stored and divide it by two when
+ // it is loaded to make sure that we always store an even number. In the long string
+ // representation, we can ignore this because we can assume that we always allocate
+ // an even amount of value_types.
+ //
+ // If the MSB is used for the short-flag, the max_size() is numeric_limits<size_type>::max() / 2.
+ // This does not impact the short string representation, since we never need the MSB
+ // for representing the size of a short string anyway.
+
+# ifdef _LIBCPP_BIG_ENDIAN
+ static const size_type __endian_factor = 2;
+# else
+ static const size_type __endian_factor = 1;
+# endif
+
+#else // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+
+# ifdef _LIBCPP_BIG_ENDIAN
+ static const size_type __endian_factor = 1;
+# else
+ static const size_type __endian_factor = 2;
+# endif
+
+ // Attribute 'packed' is used to keep the layout compatible with the
+ // previous definition that did not use bit fields. This is because on
+ // some platforms bit fields have a default size rather than the actual
+ // size used, e.g., it is 4 bytes on AIX. See D128285 for details.
+ struct __long {
+ struct _LIBCPP_PACKED {
+ size_type __is_long_ : 1;
+ size_type __cap_ : sizeof(size_type) * CHAR_BIT - 1;
+ };
+ size_type __size_;
+ pointer __data_;
+ };
+
+ enum { __min_cap = (sizeof(__long) - 1) / sizeof(value_type) > 2 ? (sizeof(__long) - 1) / sizeof(value_type) : 2 };
+
+ struct __short {
+ struct _LIBCPP_PACKED {
+ unsigned char __is_long_ : 1;
+ unsigned char __size_ : 7;
+ };
+ char __padding_[sizeof(value_type) - 1];
+ value_type __data_[__min_cap];
+ };
+
+#endif // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+
+ static_assert(sizeof(__short) == (sizeof(value_type) * (__min_cap + 1)), "__short has an unexpected size.");
+
+ union __rep {
+ __short __s;
+ __long __l;
+ };
+
+ __compressed_pair<__rep, allocator_type> __r_;
+
+ // Construct a string with the given allocator and enough storage to hold `__size` characters, but
+ // don't initialize the characters. The contents of the string, including the null terminator, must be
+ // initialized separately.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(
+ __uninitialized_size_tag, size_type __size, const allocator_type& __a)
+ : __r_(__default_init_tag(), __a) {
+ if (__size > max_size())
+ __throw_length_error();
+ if (__fits_in_sso(__size)) {
+ __r_.first() = __rep();
+ __set_short_size(__size);
+ } else {
+ auto __capacity = __recommend(__size) + 1;
+ auto __allocation = __alloc_traits::allocate(__alloc(), __capacity);
+ __begin_lifetime(__allocation, __capacity);
+ __set_long_cap(__capacity);
+ __set_long_pointer(__allocation);
+ __set_long_size(__size);
+ }
+ __annotate_new(__size);
+ }
+
+ template <class _Iter, class _Sent>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ basic_string(__init_with_sentinel_tag, _Iter __first, _Sent __last, const allocator_type& __a)
+ : __r_(__default_init_tag(), __a) {
+ __init_with_sentinel(std::move(__first), std::move(__last));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator __make_iterator(pointer __p) {
+#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS_IN_STRING
+ // Bound the iterator according to the size (and not the capacity, unlike vector).
+ //
+ // By the Standard, string iterators are generally not guaranteed to stay valid when the container is modified,
+ // regardless of whether reallocation occurs. This allows us to check for out-of-bounds accesses using logical size,
+ // a stricter check, since correct code can never rely on being able to access newly-added elements via an existing
+ // iterator.
+ return std::__make_bounded_iter(
+ std::__wrap_iter<pointer>(__p),
+ std::__wrap_iter<pointer>(__get_pointer()),
+ std::__wrap_iter<pointer>(__get_pointer() + size()));
+#else
+ return iterator(__p);
+#endif // _LIBCPP_ABI_BOUNDED_ITERATORS_IN_STRING
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator __make_const_iterator(const_pointer __p) const {
+#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS_IN_STRING
+ // Bound the iterator according to the size (and not the capacity, unlike vector).
+ return std::__make_bounded_iter(
+ std::__wrap_iter<const_pointer>(__p),
+ std::__wrap_iter<const_pointer>(__get_pointer()),
+ std::__wrap_iter<const_pointer>(__get_pointer() + size()));
+#else
+ return const_iterator(__p);
+#endif // _LIBCPP_ABI_BOUNDED_ITERATORS_IN_STRING
+ }
+
+public:
+ _LIBCPP_TEMPLATE_DATA_VIS static const size_type npos = -1;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string()
+ _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
+ : __r_(__value_init_tag(), __default_init_tag()) {
+ __annotate_new(0);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(const allocator_type& __a)
+#if _LIBCPP_STD_VER <= 14
+ _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
+#else
+ _NOEXCEPT
+#endif
+ : __r_(__value_init_tag(), __a) {
+ __annotate_new(0);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS basic_string(const basic_string& __str)
+ : __r_(__default_init_tag(), __alloc_traits::select_on_container_copy_construction(__str.__alloc())) {
+ if (!__str.__is_long()) {
+ __r_.first() = __str.__r_.first();
+ __annotate_new(__get_short_size());
+ } else
+ __init_copy_ctor_external(std::__to_address(__str.__get_long_pointer()), __str.__get_long_size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS
+ basic_string(const basic_string& __str, const allocator_type& __a)
+ : __r_(__default_init_tag(), __a) {
+ if (!__str.__is_long()) {
+ __r_.first() = __str.__r_.first();
+ __annotate_new(__get_short_size());
+ } else
+ __init_copy_ctor_external(std::__to_address(__str.__get_long_pointer()), __str.__get_long_size());
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(basic_string&& __str)
+# if _LIBCPP_STD_VER <= 14
+ _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
+# else
+ _NOEXCEPT
+# endif
+ // Turning off ASan instrumentation for variable initialization with _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS
+ // does not work consistently during initialization of __r_, so we instead unpoison __str's memory manually first.
+ // __str's memory needs to be unpoisoned only in the case where it's a short string.
+ : __r_([](basic_string& __s) -> decltype(__s.__r_)&& {
+ if (!__s.__is_long())
+ __s.__annotate_delete();
+ return std::move(__s.__r_);
+ }(__str)) {
+ __str.__r_.first() = __rep();
+ __str.__annotate_new(0);
+ if (!__is_long())
+ __annotate_new(size());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(basic_string&& __str, const allocator_type& __a)
+ : __r_(__default_init_tag(), __a) {
+ if (__str.__is_long() && __a != __str.__alloc()) // copy, not move
+ __init(std::__to_address(__str.__get_long_pointer()), __str.__get_long_size());
+ else {
+ if (__libcpp_is_constant_evaluated())
+ __r_.first() = __rep();
+ if (!__str.__is_long())
+ __str.__annotate_delete();
+ __r_.first() = __str.__r_.first();
+ __str.__r_.first() = __rep();
+ __str.__annotate_new(0);
+ if (!__is_long() && this != &__str)
+ __annotate_new(size());
+ }
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ template <__enable_if_t<__is_allocator<_Allocator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(const _CharT* __s)
+ : __r_(__default_init_tag(), __default_init_tag()) {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "basic_string(const char*) detected nullptr");
+ __init(__s, traits_type::length(__s));
+ }
+
+ template <__enable_if_t<__is_allocator<_Allocator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(const _CharT* __s, const _Allocator& __a)
+ : __r_(__default_init_tag(), __a) {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "basic_string(const char*, allocator) detected nullptr");
+ __init(__s, traits_type::length(__s));
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ basic_string(nullptr_t) = delete;
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(const _CharT* __s, size_type __n)
+ : __r_(__default_init_tag(), __default_init_tag()) {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "basic_string(const char*, n) detected nullptr");
+ __init(__s, __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ basic_string(const _CharT* __s, size_type __n, const _Allocator& __a)
+ : __r_(__default_init_tag(), __a) {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "basic_string(const char*, n, allocator) detected nullptr");
+ __init(__s, __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(size_type __n, _CharT __c)
+ : __r_(__default_init_tag(), __default_init_tag()) {
+ __init(__n, __c);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string(
+ basic_string&& __str, size_type __pos, const _Allocator& __alloc = _Allocator())
+ : basic_string(std::move(__str), __pos, npos, __alloc) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string(
+ basic_string&& __str, size_type __pos, size_type __n, const _Allocator& __alloc = _Allocator())
+ : __r_(__default_init_tag(), __alloc) {
+ if (__pos > __str.size())
+ __throw_out_of_range();
+
+ auto __len = std::min<size_type>(__n, __str.size() - __pos);
+ if (__alloc_traits::is_always_equal::value || __alloc == __str.__alloc()) {
+ __move_assign(std::move(__str), __pos, __len);
+ } else {
+ // Perform a copy because the allocators are not compatible.
+ __init(__str.data() + __pos, __len);
+ }
+ }
+#endif
+
+ template <__enable_if_t<__is_allocator<_Allocator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(size_type __n, _CharT __c, const _Allocator& __a)
+ : __r_(__default_init_tag(), __a) {
+ __init(__n, __c);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20
+ basic_string(const basic_string& __str, size_type __pos, size_type __n, const _Allocator& __a = _Allocator())
+ : __r_(__default_init_tag(), __a) {
+ size_type __str_sz = __str.size();
+ if (__pos > __str_sz)
+ __throw_out_of_range();
+ __init(__str.data() + __pos, std::min(__n, __str_sz - __pos));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ basic_string(const basic_string& __str, size_type __pos, const _Allocator& __a = _Allocator())
+ : __r_(__default_init_tag(), __a) {
+ size_type __str_sz = __str.size();
+ if (__pos > __str_sz)
+ __throw_out_of_range();
+ __init(__str.data() + __pos, __str_sz - __pos);
+ }
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20
+ basic_string(const _Tp& __t, size_type __pos, size_type __n, const allocator_type& __a = allocator_type())
+ : __r_(__default_init_tag(), __a) {
+ __self_view __sv0 = __t;
+ __self_view __sv = __sv0.substr(__pos, __n);
+ __init(__sv.data(), __sv.size());
+ }
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(const _Tp& __t)
+ : __r_(__default_init_tag(), __default_init_tag()) {
+ __self_view __sv = __t;
+ __init(__sv.data(), __sv.size());
+ }
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(const _Tp& __t, const allocator_type& __a)
+ : __r_(__default_init_tag(), __a) {
+ __self_view __sv = __t;
+ __init(__sv.data(), __sv.size());
+ }
+
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(_InputIterator __first, _InputIterator __last)
+ : __r_(__default_init_tag(), __default_init_tag()) {
+ __init(__first, __last);
+ }
+
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ basic_string(_InputIterator __first, _InputIterator __last, const allocator_type& __a)
+ : __r_(__default_init_tag(), __a) {
+ __init(__first, __last);
+ }
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_CharT> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string(
+ from_range_t, _Range&& __range, const allocator_type& __a = allocator_type())
+ : __r_(__default_init_tag(), __a) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ __init_with_size(ranges::begin(__range), ranges::end(__range), ranges::distance(__range));
+ } else {
+ __init_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(initializer_list<_CharT> __il)
+ : __r_(__default_init_tag(), __default_init_tag()) {
+ __init(__il.begin(), __il.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(initializer_list<_CharT> __il, const _Allocator& __a)
+ : __r_(__default_init_tag(), __a) {
+ __init(__il.begin(), __il.end());
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ inline _LIBCPP_CONSTEXPR_SINCE_CXX20 ~basic_string() {
+ __annotate_delete();
+ if (__is_long())
+ __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 operator __self_view() const _NOEXCEPT {
+ return __self_view(data(), size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS basic_string&
+ operator=(const basic_string& __str);
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator=(const _Tp& __t) {
+ __self_view __sv = __t;
+ return assign(__sv);
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ operator=(basic_string&& __str) noexcept(__noexcept_move_assign_container<_Allocator, __alloc_traits>::value) {
+ __move_assign(__str, integral_constant<bool, __alloc_traits::propagate_on_container_move_assignment::value>());
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator=(initializer_list<value_type> __il) {
+ return assign(__il.begin(), __il.size());
+ }
+#endif
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator=(const value_type* __s) {
+ return assign(__s);
+ }
+#if _LIBCPP_STD_VER >= 23
+ basic_string& operator=(nullptr_t) = delete;
+#endif
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator=(value_type __c);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator begin() _NOEXCEPT {
+ return __make_iterator(__get_pointer());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator begin() const _NOEXCEPT {
+ return __make_const_iterator(__get_pointer());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator end() _NOEXCEPT {
+ return __make_iterator(__get_pointer() + size());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator end() const _NOEXCEPT {
+ return __make_const_iterator(__get_pointer() + size());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reverse_iterator rbegin() _NOEXCEPT {
+ return reverse_iterator(end());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reverse_iterator rbegin() const _NOEXCEPT {
+ return const_reverse_iterator(end());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reverse_iterator rend() _NOEXCEPT {
+ return reverse_iterator(begin());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reverse_iterator rend() const _NOEXCEPT {
+ return const_reverse_iterator(begin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reverse_iterator crbegin() const _NOEXCEPT {
+ return rbegin();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type size() const _NOEXCEPT {
+ return __is_long() ? __get_long_size() : __get_short_size();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type length() const _NOEXCEPT { return size(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type max_size() const _NOEXCEPT {
+ size_type __m = __alloc_traits::max_size(__alloc());
+ if (__m <= std::numeric_limits<size_type>::max() / 2) {
+ return __m - __alignment;
+ } else {
+ bool __uses_lsb = __endian_factor == 2;
+ return __uses_lsb ? __m - __alignment : (__m / 2) - __alignment;
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type capacity() const _NOEXCEPT {
+ return (__is_long() ? __get_long_cap() : static_cast<size_type>(__min_cap)) - 1;
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 void resize(size_type __n, value_type __c);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void resize(size_type __n) { resize(__n, value_type()); }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 void reserve(size_type __requested_capacity);
+
+#if _LIBCPP_STD_VER >= 23
+ template <class _Op>
+ _LIBCPP_HIDE_FROM_ABI constexpr void resize_and_overwrite(size_type __n, _Op __op) {
+ __resize_default_init(__n);
+ __erase_to_end(std::move(__op)(data(), _LIBCPP_AUTO_CAST(__n)));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __resize_default_init(size_type __n);
+
+#if _LIBCPP_STD_VER < 26 || defined(_LIBCPP_ENABLE_CXX26_REMOVED_STRING_RESERVE)
+ _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_HIDE_FROM_ABI void reserve() _NOEXCEPT { shrink_to_fit(); }
+#endif
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void shrink_to_fit() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void clear() _NOEXCEPT;
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool empty() const _NOEXCEPT {
+ return size() == 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference operator[](size_type __pos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__pos <= size(), "string index out of bounds");
+ if (__builtin_constant_p(__pos) && !__fits_in_sso(__pos)) {
+ return *(__get_long_pointer() + __pos);
+ }
+ return *(data() + __pos);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference operator[](size_type __pos) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__pos <= size(), "string index out of bounds");
+ if (__builtin_constant_p(__pos) && !__fits_in_sso(__pos)) {
+ return *(__get_long_pointer() + __pos);
+ }
+ return *(__get_pointer() + __pos);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference at(size_type __n) const;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 reference at(size_type __n);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator+=(const basic_string& __str) {
+ return append(__str);
+ }
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string >::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ operator+=(const _Tp& __t) {
+ __self_view __sv = __t;
+ return append(__sv);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator+=(const value_type* __s) {
+ return append(__s);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator+=(value_type __c) {
+ push_back(__c);
+ return *this;
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator+=(initializer_list<value_type> __il) {
+ return append(__il);
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& append(const basic_string& __str) {
+ return append(__str.data(), __str.size());
+ }
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ append(const _Tp& __t) {
+ __self_view __sv = __t;
+ return append(__sv.data(), __sv.size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& append(const basic_string& __str, size_type __pos, size_type __n = npos);
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20
+
+ basic_string&
+ append(const _Tp& __t, size_type __pos, size_type __n = npos);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& append(const value_type* __s, size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& append(const value_type* __s);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& append(size_type __n, value_type __c);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __append_default_init(size_type __n);
+
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ append(_InputIterator __first, _InputIterator __last) {
+ const basic_string __temp(__first, __last, __alloc());
+ append(__temp.data(), __temp.size());
+ return *this;
+ }
+
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ append(_ForwardIterator __first, _ForwardIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_CharT> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string& append_range(_Range&& __range) {
+ insert_range(end(), std::forward<_Range>(__range));
+ return *this;
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& append(initializer_list<value_type> __il) {
+ return append(__il.begin(), __il.size());
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 void push_back(value_type __c);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void pop_back();
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference front() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "string::front(): string is empty");
+ return *__get_pointer();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference front() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "string::front(): string is empty");
+ return *data();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference back() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "string::back(): string is empty");
+ return *(__get_pointer() + size() - 1);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference back() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "string::back(): string is empty");
+ return *(data() + size() - 1);
+ }
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ assign(const _Tp& __t) {
+ __self_view __sv = __t;
+ return assign(__sv.data(), __sv.size());
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI constexpr void __move_assign(basic_string&& __str, size_type __pos, size_type __len) {
+ // Pilfer the allocation from __str.
+ _LIBCPP_ASSERT_INTERNAL(__alloc() == __str.__alloc(), "__move_assign called with wrong allocator");
+ size_type __old_sz = __str.size();
+ if (!__str.__is_long())
+ __str.__annotate_delete();
+ __r_.first() = __str.__r_.first();
+ __str.__r_.first() = __rep();
+ __str.__annotate_new(0);
+
+ _Traits::move(data(), data() + __pos, __len);
+ __set_size(__len);
+ _Traits::assign(data()[__len], value_type());
+
+ if (!__is_long()) {
+ __annotate_new(__len);
+ } else if (__old_sz > __len) {
+ __annotate_shrink(__old_sz);
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& assign(const basic_string& __str) {
+ return *this = __str;
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ assign(basic_string&& __str) noexcept(__noexcept_move_assign_container<_Allocator, __alloc_traits>::value) {
+ *this = std::move(__str);
+ return *this;
+ }
+#endif
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& assign(const basic_string& __str, size_type __pos, size_type __n = npos);
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ assign(const _Tp& __t, size_type __pos, size_type __n = npos);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& assign(const value_type* __s, size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& assign(const value_type* __s);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& assign(size_type __n, value_type __c);
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ assign(_InputIterator __first, _InputIterator __last);
+
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ assign(_ForwardIterator __first, _ForwardIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_CharT> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string& assign_range(_Range&& __range) {
+ if constexpr (__string_is_trivial_iterator<ranges::iterator_t<_Range>>::value &&
+ (ranges::forward_range<_Range> || ranges::sized_range<_Range>)) {
+ size_type __n = static_cast<size_type>(ranges::distance(__range));
+ __assign_trivial(ranges::begin(__range), ranges::end(__range), __n);
+
+ } else {
+ __assign_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+
+ return *this;
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& assign(initializer_list<value_type> __il) {
+ return assign(__il.begin(), __il.size());
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ insert(size_type __pos1, const basic_string& __str) {
+ return insert(__pos1, __str.data(), __str.size());
+ }
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ insert(size_type __pos1, const _Tp& __t) {
+ __self_view __sv = __t;
+ return insert(__pos1, __sv.data(), __sv.size());
+ }
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ insert(size_type __pos1, const _Tp& __t, size_type __pos2, size_type __n = npos);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ insert(size_type __pos1, const basic_string& __str, size_type __pos2, size_type __n = npos);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& insert(size_type __pos, const value_type* __s, size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& insert(size_type __pos, const value_type* __s);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& insert(size_type __pos, size_type __n, value_type __c);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator insert(const_iterator __pos, value_type __c);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_CharT> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator insert_range(const_iterator __position, _Range&& __range) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ return __insert_with_size(__position, ranges::begin(__range), ranges::end(__range), __n);
+
+ } else {
+ basic_string __temp(from_range, std::forward<_Range>(__range), __alloc());
+ return insert(__position, __temp.data(), __temp.data() + __temp.size());
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
+ insert(const_iterator __pos, size_type __n, value_type __c) {
+ difference_type __p = __pos - begin();
+ insert(static_cast<size_type>(__p), __n, __c);
+ return begin() + __p;
+ }
+
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
+ insert(const_iterator __pos, _InputIterator __first, _InputIterator __last);
+
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
+ insert(const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last);
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
+ insert(const_iterator __pos, initializer_list<value_type> __il) {
+ return insert(__pos, __il.begin(), __il.end());
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& erase(size_type __pos = 0, size_type __n = npos);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator erase(const_iterator __pos);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator erase(const_iterator __first, const_iterator __last);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(size_type __pos1, size_type __n1, const basic_string& __str) {
+ return replace(__pos1, __n1, __str.data(), __str.size());
+ }
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(size_type __pos1, size_type __n1, const _Tp& __t) {
+ __self_view __sv = __t;
+ return replace(__pos1, __n1, __sv.data(), __sv.size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2 = npos);
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(size_type __pos1, size_type __n1, const _Tp& __t, size_type __pos2, size_type __n2 = npos);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& replace(size_type __pos, size_type __n1, const value_type* __s);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& replace(size_type __pos, size_type __n1, size_type __n2, value_type __c);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(const_iterator __i1, const_iterator __i2, const basic_string& __str) {
+ return replace(
+ static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __str.data(), __str.size());
+ }
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(const_iterator __i1, const_iterator __i2, const _Tp& __t) {
+ __self_view __sv = __t;
+ return replace(__i1 - begin(), __i2 - __i1, __sv);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n) {
+ return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s, __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(const_iterator __i1, const_iterator __i2, const value_type* __s) {
+ return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(const_iterator __i1, const_iterator __i2, size_type __n, value_type __c) {
+ return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __n, __c);
+ }
+
+ template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(const_iterator __i1, const_iterator __i2, _InputIterator __j1, _InputIterator __j2);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_CharT> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string&
+ replace_with_range(const_iterator __i1, const_iterator __i2, _Range&& __range) {
+ basic_string __temp(from_range, std::forward<_Range>(__range), __alloc());
+ return replace(__i1, __i2, __temp);
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ replace(const_iterator __i1, const_iterator __i2, initializer_list<value_type> __il) {
+ return replace(__i1, __i2, __il.begin(), __il.end());
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type copy(value_type* __s, size_type __n, size_type __pos = 0) const;
+
+#if _LIBCPP_STD_VER <= 20
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string
+ substr(size_type __pos = 0, size_type __n = npos) const {
+ return basic_string(*this, __pos, __n);
+ }
+#else
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string substr(size_type __pos = 0, size_type __n = npos) const& {
+ return basic_string(*this, __pos, __n);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr basic_string substr(size_type __pos = 0, size_type __n = npos) && {
+ return basic_string(std::move(*this), __pos, __n);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(basic_string& __str)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT;
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>);
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const value_type* c_str() const _NOEXCEPT { return data(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const value_type* data() const _NOEXCEPT {
+ return std::__to_address(__get_pointer());
+ }
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 value_type* data() _NOEXCEPT {
+ return std::__to_address(__get_pointer());
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 allocator_type get_allocator() const _NOEXCEPT {
+ return __alloc();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find(const _Tp& __t, size_type __pos = 0) const _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type find(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type find(value_type __c, size_type __pos = 0) const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ rfind(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ rfind(const _Tp& __t, size_type __pos = npos) const _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type rfind(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ rfind(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type rfind(value_type __c, size_type __pos = npos) const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_of(const _Tp& __t, size_type __pos = 0) const _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_of(const _Tp& __t, size_type __pos = npos) const _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_not_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_not_of(const _Tp& __t, size_type __pos = 0) const _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_not_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_first_not_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_not_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_not_of(const _Tp& __t, size_type __pos = npos) const _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_not_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ find_last_not_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 int compare(const basic_string& __str) const _NOEXCEPT;
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 int
+ compare(const _Tp& __t) const _NOEXCEPT;
+
+ template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> = 0>
+ _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 int
+ compare(size_type __pos1, size_type __n1, const _Tp& __t) const;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 int
+ compare(size_type __pos1, size_type __n1, const basic_string& __str) const;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 int
+ compare(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2 = npos) const;
+
+ template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string>::value,
+ int> = 0>
+ inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 int
+ compare(size_type __pos1, size_type __n1, const _Tp& __t, size_type __pos2, size_type __n2 = npos) const;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 int compare(const value_type* __s) const _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 int compare(size_type __pos1, size_type __n1, const value_type* __s) const;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 int
+ compare(size_type __pos1, size_type __n1, const value_type* __s, size_type __n2) const;
+
+#if _LIBCPP_STD_VER >= 20
+ constexpr _LIBCPP_HIDE_FROM_ABI bool starts_with(__self_view __sv) const noexcept {
+ return __self_view(data(), size()).starts_with(__sv);
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool starts_with(value_type __c) const noexcept {
+ return !empty() && _Traits::eq(front(), __c);
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool starts_with(const value_type* __s) const noexcept {
+ return starts_with(__self_view(__s));
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool ends_with(__self_view __sv) const noexcept {
+ return __self_view(data(), size()).ends_with(__sv);
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool ends_with(value_type __c) const noexcept {
+ return !empty() && _Traits::eq(back(), __c);
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool ends_with(const value_type* __s) const noexcept {
+ return ends_with(__self_view(__s));
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ constexpr _LIBCPP_HIDE_FROM_ABI bool contains(__self_view __sv) const noexcept {
+ return __self_view(data(), size()).contains(__sv);
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool contains(value_type __c) const noexcept {
+ return __self_view(data(), size()).contains(__c);
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool contains(const value_type* __s) const {
+ return __self_view(data(), size()).contains(__s);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __invariants() const;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __clear_and_shrink() _NOEXCEPT;
+
+private:
+ template <class _Alloc>
+ inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool friend
+ operator==(const basic_string<char, char_traits<char>, _Alloc>& __lhs,
+ const basic_string<char, char_traits<char>, _Alloc>& __rhs) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __shrink_or_extend(size_type __target_capacity);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS bool
+ __is_long() const _NOEXCEPT {
+ if (__libcpp_is_constant_evaluated() && __builtin_constant_p(__r_.first().__l.__is_long_)) {
+ return __r_.first().__l.__is_long_;
+ }
+ return __r_.first().__s.__is_long_;
+ }
+
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __begin_lifetime(pointer __begin, size_type __n) {
+#if _LIBCPP_STD_VER >= 20
+ if (__libcpp_is_constant_evaluated()) {
+ for (size_type __i = 0; __i != __n; ++__i)
+ std::construct_at(std::addressof(__begin[__i]));
+ }
+#else
+ (void)__begin;
+ (void)__n;
+#endif // _LIBCPP_STD_VER >= 20
+ }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI static bool __fits_in_sso(size_type __sz) { return __sz < __min_cap; }
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __assign_trivial(_Iterator __first, _Sentinel __last, size_type __n);
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __assign_with_sentinel(_Iterator __first, _Sentinel __last);
+
+ // Copy [__first, __last) into [__dest, __dest + (__last - __first)). Assumes that the ranges don't overlap.
+ template <class _ForwardIter, class _Sent>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 static value_type*
+ __copy_non_overlapping_range(_ForwardIter __first, _Sent __last, value_type* __dest) {
+#ifndef _LIBCPP_CXX03_LANG
+ if constexpr (__libcpp_is_contiguous_iterator<_ForwardIter>::value &&
+ is_same<value_type, __iter_value_type<_ForwardIter>>::value && is_same<_ForwardIter, _Sent>::value) {
+ traits_type::copy(__dest, std::__to_address(__first), __last - __first);
+ return __dest + (__last - __first);
+ }
+#endif
+
+ for (; __first != __last; ++__first)
+ traits_type::assign(*__dest++, *__first);
+ return __dest;
+ }
+
+ template <class _ForwardIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 iterator
+ __insert_from_safe_copy(size_type __n, size_type __ip, _ForwardIterator __first, _Sentinel __last) {
+ size_type __sz = size();
+ size_type __cap = capacity();
+ value_type* __p;
+ if (__cap - __sz >= __n) {
+ __annotate_increase(__n);
+ __p = std::__to_address(__get_pointer());
+ size_type __n_move = __sz - __ip;
+ if (__n_move != 0)
+ traits_type::move(__p + __ip + __n, __p + __ip, __n_move);
+ } else {
+ __grow_by_without_replace(__cap, __sz + __n - __cap, __sz, __ip, 0, __n);
+ __p = std::__to_address(__get_long_pointer());
+ }
+ __sz += __n;
+ __set_size(__sz);
+ traits_type::assign(__p[__sz], value_type());
+ __copy_non_overlapping_range(__first, __last, __p + __ip);
+
+ return begin() + __ip;
+ }
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
+ __insert_with_size(const_iterator __pos, _Iterator __first, _Sentinel __last, size_type __n);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 allocator_type& __alloc() _NOEXCEPT { return __r_.second(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const allocator_type& __alloc() const _NOEXCEPT { return __r_.second(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS void
+ __set_short_size(size_type __s) _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(__s < __min_cap, "__s should never be greater than or equal to the short string capacity");
+ __r_.first().__s.__size_ = __s;
+ __r_.first().__s.__is_long_ = false;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS size_type
+ __get_short_size() const _NOEXCEPT {
+ _LIBCPP_ASSERT_INTERNAL(!__r_.first().__s.__is_long_, "String has to be short when trying to get the short size");
+ return __r_.first().__s.__size_;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __set_long_size(size_type __s) _NOEXCEPT {
+ __r_.first().__l.__size_ = __s;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type __get_long_size() const _NOEXCEPT {
+ return __r_.first().__l.__size_;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __set_size(size_type __s) _NOEXCEPT {
+ if (__is_long())
+ __set_long_size(__s);
+ else
+ __set_short_size(__s);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __set_long_cap(size_type __s) _NOEXCEPT {
+ __r_.first().__l.__cap_ = __s / __endian_factor;
+ __r_.first().__l.__is_long_ = true;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type __get_long_cap() const _NOEXCEPT {
+ return __r_.first().__l.__cap_ * __endian_factor;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __set_long_pointer(pointer __p) _NOEXCEPT {
+ __r_.first().__l.__data_ = __p;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pointer __get_long_pointer() _NOEXCEPT {
+ return _LIBCPP_ASAN_VOLATILE_WRAPPER(__r_.first().__l.__data_);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_pointer __get_long_pointer() const _NOEXCEPT {
+ return _LIBCPP_ASAN_VOLATILE_WRAPPER(__r_.first().__l.__data_);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS pointer
+ __get_short_pointer() _NOEXCEPT {
+ return _LIBCPP_ASAN_VOLATILE_WRAPPER(pointer_traits<pointer>::pointer_to(__r_.first().__s.__data_[0]));
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS const_pointer
+ __get_short_pointer() const _NOEXCEPT {
+ return _LIBCPP_ASAN_VOLATILE_WRAPPER(pointer_traits<const_pointer>::pointer_to(__r_.first().__s.__data_[0]));
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pointer __get_pointer() _NOEXCEPT {
+ return __is_long() ? __get_long_pointer() : __get_short_pointer();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_pointer __get_pointer() const _NOEXCEPT {
+ return __is_long() ? __get_long_pointer() : __get_short_pointer();
+ }
+
+ // The following functions are no-ops outside of AddressSanitizer mode.
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ __annotate_contiguous_container(const void* __old_mid, const void* __new_mid) const {
+ (void)__old_mid;
+ (void)__new_mid;
+#if !defined(_LIBCPP_HAS_NO_ASAN) && defined(_LIBCPP_INSTRUMENTED_WITH_ASAN)
+ #if defined(__APPLE__)
+ // TODO: remove after addressing issue #96099 (https://github.com/llvm/llvm-project/issues/96099)
+ if(!__is_long())
+ return;
+ #endif
+ std::__annotate_contiguous_container<_Allocator>(data(), data() + capacity() + 1, __old_mid, __new_mid);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __annotate_new(size_type __current_size) const _NOEXCEPT {
+ (void)__current_size;
+#if !defined(_LIBCPP_HAS_NO_ASAN) && defined(_LIBCPP_INSTRUMENTED_WITH_ASAN)
+ if (!__libcpp_is_constant_evaluated())
+ __annotate_contiguous_container(data() + capacity() + 1, data() + __current_size + 1);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __annotate_delete() const _NOEXCEPT {
+#if !defined(_LIBCPP_HAS_NO_ASAN) && defined(_LIBCPP_INSTRUMENTED_WITH_ASAN)
+ if (!__libcpp_is_constant_evaluated())
+ __annotate_contiguous_container(data() + size() + 1, data() + capacity() + 1);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __annotate_increase(size_type __n) const _NOEXCEPT {
+ (void)__n;
+#if !defined(_LIBCPP_HAS_NO_ASAN) && defined(_LIBCPP_INSTRUMENTED_WITH_ASAN)
+ if (!__libcpp_is_constant_evaluated())
+ __annotate_contiguous_container(data() + size() + 1, data() + size() + 1 + __n);
+#endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __annotate_shrink(size_type __old_size) const _NOEXCEPT {
+ (void)__old_size;
+#if !defined(_LIBCPP_HAS_NO_ASAN) && defined(_LIBCPP_INSTRUMENTED_WITH_ASAN)
+ if (!__libcpp_is_constant_evaluated())
+ __annotate_contiguous_container(data() + __old_size + 1, data() + size() + 1);
+#endif
+ }
+
+ template <size_type __a>
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type __align_it(size_type __s) _NOEXCEPT {
+ return (__s + (__a - 1)) & ~(__a - 1);
+ }
+ enum { __alignment = 8 };
+ static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type __recommend(size_type __s) _NOEXCEPT {
+ if (__s < __min_cap) {
+ return static_cast<size_type>(__min_cap) - 1;
+ }
+ const size_type __boundary = sizeof(value_type) < __alignment ? __alignment / sizeof(value_type) : __endian_factor;
+ size_type __guess = __align_it<__boundary>(__s + 1) - 1;
+ if (__guess == __min_cap)
+ __guess += __endian_factor;
+ return __guess;
+ }
+
+ inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void __init(const value_type* __s, size_type __sz, size_type __reserve);
+ inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void __init(const value_type* __s, size_type __sz);
+ inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void __init(size_type __n, value_type __c);
+
+ // Slow path for the (inlined) copy constructor for 'long' strings.
+ // Always externally instantiated and not inlined.
+ // Requires that __s is zero terminated.
+ // The main reason for this function to exist is because for unstable, we
+ // want to allow inlining of the copy constructor. However, we don't want
+ // to call the __init() functions as those are marked as inline which may
+ // result in over-aggressive inlining by the compiler, where our aim is
+ // to only inline the fast path code directly in the ctor.
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE void __init_copy_ctor_external(const value_type* __s, size_type __sz);
+
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void __init(_InputIterator __first, _InputIterator __last);
+
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void __init(_ForwardIterator __first, _ForwardIterator __last);
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ __init_with_sentinel(_InputIterator __first, _Sentinel __last);
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ __init_with_size(_InputIterator __first, _Sentinel __last, size_type __sz);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20
+#if _LIBCPP_ABI_VERSION >= 2 // We want to use the function in the dylib in ABIv1
+ _LIBCPP_HIDE_FROM_ABI
+#endif
+ _LIBCPP_DEPRECATED_("use __grow_by_without_replace") void __grow_by(
+ size_type __old_cap,
+ size_type __delta_cap,
+ size_type __old_sz,
+ size_type __n_copy,
+ size_type __n_del,
+ size_type __n_add = 0);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __grow_by_without_replace(
+ size_type __old_cap,
+ size_type __delta_cap,
+ size_type __old_sz,
+ size_type __n_copy,
+ size_type __n_del,
+ size_type __n_add = 0);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 void __grow_by_and_replace(
+ size_type __old_cap,
+ size_type __delta_cap,
+ size_type __old_sz,
+ size_type __n_copy,
+ size_type __n_del,
+ size_type __n_add,
+ const value_type* __p_new_stuff);
+
+ // __assign_no_alias is invoked for assignment operations where we
+ // have proof that the input does not alias the current instance.
+ // For example, operator=(basic_string) performs a 'self' check.
+ template <bool __is_short>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE basic_string& __assign_no_alias(const value_type* __s, size_type __n);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __erase_to_end(size_type __pos) {
+ __null_terminate_at(std::__to_address(__get_pointer()), __pos);
+ }
+
+ // __erase_external_with_move is invoked for erase() invocations where
+ // `n ~= npos`, likely requiring memory moves on the string data.
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE void __erase_external_with_move(size_type __pos, size_type __n);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __copy_assign_alloc(const basic_string& __str) {
+ __copy_assign_alloc(
+ __str, integral_constant<bool, __alloc_traits::propagate_on_container_copy_assignment::value>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __copy_assign_alloc(const basic_string& __str, true_type) {
+ if (__alloc() == __str.__alloc())
+ __alloc() = __str.__alloc();
+ else {
+ if (!__str.__is_long()) {
+ __clear_and_shrink();
+ __alloc() = __str.__alloc();
+ } else {
+ __annotate_delete();
+ allocator_type __a = __str.__alloc();
+ auto __allocation = std::__allocate_at_least(__a, __str.__get_long_cap());
+ __begin_lifetime(__allocation.ptr, __allocation.count);
+ if (__is_long())
+ __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
+ __alloc() = std::move(__a);
+ __set_long_pointer(__allocation.ptr);
+ __set_long_cap(__allocation.count);
+ __set_long_size(__str.size());
+ __annotate_new(__get_long_size());
+ }
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ __copy_assign_alloc(const basic_string&, false_type) _NOEXCEPT {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ __move_assign(basic_string& __str, false_type) noexcept(__alloc_traits::is_always_equal::value);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS void
+ __move_assign(basic_string& __str, true_type)
+# if _LIBCPP_STD_VER >= 17
+ noexcept;
+# else
+ noexcept(is_nothrow_move_assignable<allocator_type>::value);
+# endif
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign_alloc(basic_string& __str)
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_move_assignment::value ||
+ is_nothrow_move_assignable<allocator_type>::value) {
+ __move_assign_alloc(
+ __str, integral_constant<bool, __alloc_traits::propagate_on_container_move_assignment::value>());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign_alloc(basic_string& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
+ __alloc() = std::move(__c.__alloc());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign_alloc(basic_string&, false_type) _NOEXCEPT {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE basic_string& __assign_external(const value_type* __s);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE basic_string& __assign_external(const value_type* __s, size_type __n);
+
+ // Assigns the value in __s, guaranteed to be __n < __min_cap in length.
+ inline _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& __assign_short(const value_type* __s, size_type __n) {
+ size_type __old_size = size();
+ if (__n > __old_size)
+ __annotate_increase(__n - __old_size);
+ pointer __p =
+ __is_long() ? (__set_long_size(__n), __get_long_pointer()) : (__set_short_size(__n), __get_short_pointer());
+ traits_type::move(std::__to_address(__p), __s, __n);
+ traits_type::assign(__p[__n], value_type());
+ if (__old_size > __n)
+ __annotate_shrink(__old_size);
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string&
+ __null_terminate_at(value_type* __p, size_type __newsz) {
+ size_type __old_size = size();
+ if (__newsz > __old_size)
+ __annotate_increase(__newsz - __old_size);
+ __set_size(__newsz);
+ traits_type::assign(__p[__newsz], value_type());
+ if (__old_size > __newsz)
+ __annotate_shrink(__old_size);
+ return *this;
+ }
+
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __addr_in_range(const _Tp& __v) const {
+ return std::__is_pointer_in_range(data(), data() + size() + 1, std::addressof(__v));
+ }
+
+ _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI void __throw_length_error() const {
+ std::__throw_length_error("basic_string");
+ }
+
+ _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI void __throw_out_of_range() const {
+ std::__throw_out_of_range("basic_string");
+ }
+
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string operator+ <>(const basic_string&, const basic_string&);
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string operator+ <>(const value_type*, const basic_string&);
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string operator+ <>(value_type, const basic_string&);
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string operator+ <>(const basic_string&, const value_type*);
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string operator+ <>(const basic_string&, value_type);
+#if _LIBCPP_STD_VER >= 26
+ friend constexpr basic_string operator+ <>(const basic_string&, type_identity_t<__self_view>);
+ friend constexpr basic_string operator+ <>(type_identity_t<__self_view>, const basic_string&);
+#endif
+};
+
+// These declarations must appear before any functions are implicitly used
+// so that they have the correct visibility specifier.
+#define _LIBCPP_DECLARE(...) extern template __VA_ARGS__;
+#ifdef _LIBCPP_ABI_STRING_OPTIMIZED_EXTERNAL_INSTANTIATION
+_LIBCPP_STRING_UNSTABLE_EXTERN_TEMPLATE_LIST(_LIBCPP_DECLARE, char)
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+_LIBCPP_STRING_UNSTABLE_EXTERN_TEMPLATE_LIST(_LIBCPP_DECLARE, wchar_t)
+# endif
+#else
+_LIBCPP_STRING_V1_EXTERN_TEMPLATE_LIST(_LIBCPP_DECLARE, char)
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+_LIBCPP_STRING_V1_EXTERN_TEMPLATE_LIST(_LIBCPP_DECLARE, wchar_t)
+# endif
+#endif
+#undef _LIBCPP_DECLARE
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _CharT = __iter_value_type<_InputIterator>,
+ class _Allocator = allocator<_CharT>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value> >
+basic_string(_InputIterator, _InputIterator, _Allocator = _Allocator())
+ -> basic_string<_CharT, char_traits<_CharT>, _Allocator>;
+
+template <class _CharT,
+ class _Traits,
+ class _Allocator = allocator<_CharT>,
+ class = enable_if_t<__is_allocator<_Allocator>::value> >
+explicit basic_string(basic_string_view<_CharT, _Traits>,
+ const _Allocator& = _Allocator()) -> basic_string<_CharT, _Traits, _Allocator>;
+
+template <class _CharT,
+ class _Traits,
+ class _Allocator = allocator<_CharT>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>,
+ class _Sz = typename allocator_traits<_Allocator>::size_type >
+basic_string(basic_string_view<_CharT, _Traits>, _Sz, _Sz, const _Allocator& = _Allocator())
+ -> basic_string<_CharT, _Traits, _Allocator>;
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Allocator = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<__is_allocator<_Allocator>::value> >
+basic_string(from_range_t, _Range&&, _Allocator = _Allocator())
+ -> basic_string<ranges::range_value_t<_Range>, char_traits<ranges::range_value_t<_Range>>, _Allocator>;
+#endif
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s, size_type __sz, size_type __reserve) {
+ if (__libcpp_is_constant_evaluated())
+ __r_.first() = __rep();
+ if (__reserve > max_size())
+ __throw_length_error();
+ pointer __p;
+ if (__fits_in_sso(__reserve)) {
+ __set_short_size(__sz);
+ __p = __get_short_pointer();
+ } else {
+ auto __allocation = std::__allocate_at_least(__alloc(), __recommend(__reserve) + 1);
+ __p = __allocation.ptr;
+ __begin_lifetime(__p, __allocation.count);
+ __set_long_pointer(__p);
+ __set_long_cap(__allocation.count);
+ __set_long_size(__sz);
+ }
+ traits_type::copy(std::__to_address(__p), __s, __sz);
+ traits_type::assign(__p[__sz], value_type());
+ __annotate_new(__sz);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s, size_type __sz) {
+ if (__libcpp_is_constant_evaluated())
+ __r_.first() = __rep();
+ if (__sz > max_size())
+ __throw_length_error();
+ pointer __p;
+ if (__fits_in_sso(__sz)) {
+ __set_short_size(__sz);
+ __p = __get_short_pointer();
+ } else {
+ auto __allocation = std::__allocate_at_least(__alloc(), __recommend(__sz) + 1);
+ __p = __allocation.ptr;
+ __begin_lifetime(__p, __allocation.count);
+ __set_long_pointer(__p);
+ __set_long_cap(__allocation.count);
+ __set_long_size(__sz);
+ }
+ traits_type::copy(std::__to_address(__p), __s, __sz);
+ traits_type::assign(__p[__sz], value_type());
+ __annotate_new(__sz);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE void
+basic_string<_CharT, _Traits, _Allocator>::__init_copy_ctor_external(const value_type* __s, size_type __sz) {
+ if (__libcpp_is_constant_evaluated())
+ __r_.first() = __rep();
+
+ pointer __p;
+ if (__fits_in_sso(__sz)) {
+ __p = __get_short_pointer();
+ __set_short_size(__sz);
+ } else {
+ if (__sz > max_size())
+ __throw_length_error();
+ auto __allocation = std::__allocate_at_least(__alloc(), __recommend(__sz) + 1);
+ __p = __allocation.ptr;
+ __begin_lifetime(__p, __allocation.count);
+ __set_long_pointer(__p);
+ __set_long_cap(__allocation.count);
+ __set_long_size(__sz);
+ }
+ traits_type::copy(std::__to_address(__p), __s, __sz + 1);
+ __annotate_new(__sz);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::__init(size_type __n, value_type __c) {
+ if (__libcpp_is_constant_evaluated())
+ __r_.first() = __rep();
+
+ if (__n > max_size())
+ __throw_length_error();
+ pointer __p;
+ if (__fits_in_sso(__n)) {
+ __set_short_size(__n);
+ __p = __get_short_pointer();
+ } else {
+ auto __allocation = std::__allocate_at_least(__alloc(), __recommend(__n) + 1);
+ __p = __allocation.ptr;
+ __begin_lifetime(__p, __allocation.count);
+ __set_long_pointer(__p);
+ __set_long_cap(__allocation.count);
+ __set_long_size(__n);
+ }
+ traits_type::assign(std::__to_address(__p), __n, __c);
+ traits_type::assign(__p[__n], value_type());
+ __annotate_new(__n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+basic_string<_CharT, _Traits, _Allocator>::__init(_InputIterator __first, _InputIterator __last) {
+ __init_with_sentinel(std::move(__first), std::move(__last));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+basic_string<_CharT, _Traits, _Allocator>::__init_with_sentinel(_InputIterator __first, _Sentinel __last) {
+ __r_.first() = __rep();
+ __annotate_new(0);
+
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (; __first != __last; ++__first)
+ push_back(*__first);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __annotate_delete();
+ if (__is_long())
+ __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+basic_string<_CharT, _Traits, _Allocator>::__init(_ForwardIterator __first, _ForwardIterator __last) {
+ size_type __sz = static_cast<size_type>(std::distance(__first, __last));
+ __init_with_size(__first, __last, __sz);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+basic_string<_CharT, _Traits, _Allocator>::__init_with_size(_InputIterator __first, _Sentinel __last, size_type __sz) {
+ if (__libcpp_is_constant_evaluated())
+ __r_.first() = __rep();
+
+ if (__sz > max_size())
+ __throw_length_error();
+
+ pointer __p;
+ if (__fits_in_sso(__sz)) {
+ __set_short_size(__sz);
+ __p = __get_short_pointer();
+
+ } else {
+ auto __allocation = std::__allocate_at_least(__alloc(), __recommend(__sz) + 1);
+ __p = __allocation.ptr;
+ __begin_lifetime(__p, __allocation.count);
+ __set_long_pointer(__p);
+ __set_long_cap(__allocation.count);
+ __set_long_size(__sz);
+ }
+
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ auto __end = __copy_non_overlapping_range(__first, __last, std::__to_address(__p));
+ traits_type::assign(*__end, value_type());
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ if (__is_long())
+ __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __annotate_new(__sz);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::__grow_by_and_replace(
+ size_type __old_cap,
+ size_type __delta_cap,
+ size_type __old_sz,
+ size_type __n_copy,
+ size_type __n_del,
+ size_type __n_add,
+ const value_type* __p_new_stuff) {
+ size_type __ms = max_size();
+ if (__delta_cap > __ms - __old_cap - 1)
+ __throw_length_error();
+ pointer __old_p = __get_pointer();
+ size_type __cap =
+ __old_cap < __ms / 2 - __alignment ? __recommend(std::max(__old_cap + __delta_cap, 2 * __old_cap)) : __ms - 1;
+ __annotate_delete();
+ auto __allocation = std::__allocate_at_least(__alloc(), __cap + 1);
+ pointer __p = __allocation.ptr;
+ __begin_lifetime(__p, __allocation.count);
+ if (__n_copy != 0)
+ traits_type::copy(std::__to_address(__p), std::__to_address(__old_p), __n_copy);
+ if (__n_add != 0)
+ traits_type::copy(std::__to_address(__p) + __n_copy, __p_new_stuff, __n_add);
+ size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
+ if (__sec_cp_sz != 0)
+ traits_type::copy(
+ std::__to_address(__p) + __n_copy + __n_add, std::__to_address(__old_p) + __n_copy + __n_del, __sec_cp_sz);
+ if (__old_cap + 1 != __min_cap)
+ __alloc_traits::deallocate(__alloc(), __old_p, __old_cap + 1);
+ __set_long_pointer(__p);
+ __set_long_cap(__allocation.count);
+ __old_sz = __n_copy + __n_add + __sec_cp_sz;
+ __set_long_size(__old_sz);
+ traits_type::assign(__p[__old_sz], value_type());
+ __annotate_new(__old_sz);
+}
+
+// __grow_by is deprecated because it does not set the size. It may not update the size when the size is changed, and it
+// may also not set the size at all when the string was short initially. This leads to unpredictable size value. It is
+// not removed or changed to avoid breaking the ABI.
+template <class _CharT, class _Traits, class _Allocator>
+void _LIBCPP_CONSTEXPR_SINCE_CXX20
+#if _LIBCPP_ABI_VERSION >= 2 // We want to use the function in the dylib in ABIv1
+_LIBCPP_HIDE_FROM_ABI
+#endif
+_LIBCPP_DEPRECATED_("use __grow_by_without_replace") basic_string<_CharT, _Traits, _Allocator>::__grow_by(
+ size_type __old_cap,
+ size_type __delta_cap,
+ size_type __old_sz,
+ size_type __n_copy,
+ size_type __n_del,
+ size_type __n_add) {
+ size_type __ms = max_size();
+ if (__delta_cap > __ms - __old_cap)
+ __throw_length_error();
+ pointer __old_p = __get_pointer();
+ size_type __cap =
+ __old_cap < __ms / 2 - __alignment ? __recommend(std::max(__old_cap + __delta_cap, 2 * __old_cap)) : __ms - 1;
+ __annotate_delete();
+ auto __allocation = std::__allocate_at_least(__alloc(), __cap + 1);
+ pointer __p = __allocation.ptr;
+ __begin_lifetime(__p, __allocation.count);
+ if (__n_copy != 0)
+ traits_type::copy(std::__to_address(__p), std::__to_address(__old_p), __n_copy);
+ size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
+ if (__sec_cp_sz != 0)
+ traits_type::copy(
+ std::__to_address(__p) + __n_copy + __n_add, std::__to_address(__old_p) + __n_copy + __n_del, __sec_cp_sz);
+ if (__old_cap + 1 != __min_cap)
+ __alloc_traits::deallocate(__alloc(), __old_p, __old_cap + 1);
+ __set_long_pointer(__p);
+ __set_long_cap(__allocation.count);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+void _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+basic_string<_CharT, _Traits, _Allocator>::__grow_by_without_replace(
+ size_type __old_cap,
+ size_type __delta_cap,
+ size_type __old_sz,
+ size_type __n_copy,
+ size_type __n_del,
+ size_type __n_add) {
+ _LIBCPP_SUPPRESS_DEPRECATED_PUSH
+ __grow_by(__old_cap, __delta_cap, __old_sz, __n_copy, __n_del, __n_add);
+ _LIBCPP_SUPPRESS_DEPRECATED_POP
+ __set_long_size(__old_sz - __n_del + __n_add);
+ __annotate_new(__old_sz - __n_del + __n_add);
+}
+
+// assign
+
+template <class _CharT, class _Traits, class _Allocator>
+template <bool __is_short>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::__assign_no_alias(const value_type* __s, size_type __n) {
+ size_type __cap = __is_short ? static_cast<size_type>(__min_cap) : __get_long_cap();
+ if (__n < __cap) {
+ size_type __old_size = __is_short ? __get_short_size() : __get_long_size();
+ if (__n > __old_size)
+ __annotate_increase(__n - __old_size);
+ pointer __p = __is_short ? __get_short_pointer() : __get_long_pointer();
+ __is_short ? __set_short_size(__n) : __set_long_size(__n);
+ traits_type::copy(std::__to_address(__p), __s, __n);
+ traits_type::assign(__p[__n], value_type());
+ if (__old_size > __n)
+ __annotate_shrink(__old_size);
+ } else {
+ size_type __sz = __is_short ? __get_short_size() : __get_long_size();
+ __grow_by_and_replace(__cap - 1, __n - __cap + 1, __sz, 0, __sz, __n, __s);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::__assign_external(const value_type* __s, size_type __n) {
+ size_type __cap = capacity();
+ if (__cap >= __n) {
+ size_type __old_size = size();
+ if (__n > __old_size)
+ __annotate_increase(__n - __old_size);
+ value_type* __p = std::__to_address(__get_pointer());
+ traits_type::move(__p, __s, __n);
+ return __null_terminate_at(__p, __n);
+ } else {
+ size_type __sz = size();
+ __grow_by_and_replace(__cap, __n - __cap, __sz, 0, __sz, __n, __s);
+ return *this;
+ }
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s, size_type __n) {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::assign received nullptr");
+ return (__builtin_constant_p(__n) && __fits_in_sso(__n)) ? __assign_short(__s, __n) : __assign_external(__s, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::assign(size_type __n, value_type __c) {
+ size_type __cap = capacity();
+ size_type __old_size = size();
+ if (__cap < __n) {
+ size_type __sz = size();
+ __grow_by_without_replace(__cap, __n - __cap, __sz, 0, __sz);
+ __annotate_increase(__n);
+ } else if (__n > __old_size)
+ __annotate_increase(__n - __old_size);
+ value_type* __p = std::__to_address(__get_pointer());
+ traits_type::assign(__p, __n, __c);
+ return __null_terminate_at(__p, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::operator=(value_type __c) {
+ pointer __p;
+ size_type __old_size = size();
+ if (__old_size == 0)
+ __annotate_increase(1);
+ if (__is_long()) {
+ __p = __get_long_pointer();
+ __set_long_size(1);
+ } else {
+ __p = __get_short_pointer();
+ __set_short_size(1);
+ }
+ traits_type::assign(*__p, __c);
+ traits_type::assign(*++__p, value_type());
+ if (__old_size > 1)
+ __annotate_shrink(__old_size);
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::operator=(const basic_string& __str) {
+ if (this != std::addressof(__str)) {
+ __copy_assign_alloc(__str);
+ if (!__is_long()) {
+ if (!__str.__is_long()) {
+ size_type __old_size = __get_short_size();
+ if (__get_short_size() < __str.__get_short_size())
+ __annotate_increase(__str.__get_short_size() - __get_short_size());
+ __r_.first() = __str.__r_.first();
+ if (__old_size > __get_short_size())
+ __annotate_shrink(__old_size);
+ } else {
+ return __assign_no_alias<true>(__str.data(), __str.size());
+ }
+ } else {
+ return __assign_no_alias<false>(__str.data(), __str.size());
+ }
+ }
+ return *this;
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::__move_assign(
+ basic_string& __str, false_type) noexcept(__alloc_traits::is_always_equal::value) {
+ if (__alloc() != __str.__alloc())
+ assign(__str);
+ else
+ __move_assign(__str, true_type());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_STRING_INTERNAL_MEMORY_ACCESS void
+basic_string<_CharT, _Traits, _Allocator>::__move_assign(basic_string& __str, true_type)
+# if _LIBCPP_STD_VER >= 17
+ noexcept
+# else
+ noexcept(is_nothrow_move_assignable<allocator_type>::value)
+# endif
+{
+ __annotate_delete();
+ if (__is_long()) {
+ __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
+# if _LIBCPP_STD_VER <= 14
+ if (!is_nothrow_move_assignable<allocator_type>::value) {
+ __set_short_size(0);
+ traits_type::assign(__get_short_pointer()[0], value_type());
+ __annotate_new(0);
+ }
+# endif
+ }
+ size_type __str_old_size = __str.size();
+ bool __str_was_short = !__str.__is_long();
+
+ __move_assign_alloc(__str);
+ __r_.first() = __str.__r_.first();
+ __str.__set_short_size(0);
+ traits_type::assign(__str.__get_short_pointer()[0], value_type());
+
+ if (__str_was_short && this != &__str)
+ __str.__annotate_shrink(__str_old_size);
+ else
+ // ASan annotations: was long, so object memory is unpoisoned as new.
+ // Or is same as *this, and __annotate_delete() was called.
+ __str.__annotate_new(0);
+
+ // ASan annotations: Guard against `std::string s; s = std::move(s);`
+ // You can find more here: https://en.cppreference.com/w/cpp/utility/move
+ // Quote: "Unless otherwise specified, all standard library objects that have been moved
+ // from are placed in a "valid but unspecified state", meaning the object's class
+ // invariants hold (so functions without preconditions, such as the assignment operator,
+ // can be safely used on the object after it was moved from):"
+ // Quote: "v = std::move(v); // the value of v is unspecified"
+ if (!__is_long() && &__str != this)
+ // If it is long string, delete was never called on original __str's buffer.
+ __annotate_new(__get_short_size());
+}
+
+#endif
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::assign(_InputIterator __first, _InputIterator __last) {
+ __assign_with_sentinel(__first, __last);
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+basic_string<_CharT, _Traits, _Allocator>::__assign_with_sentinel(_InputIterator __first, _Sentinel __last) {
+ const basic_string __temp(__init_with_sentinel_tag(), std::move(__first), std::move(__last), __alloc());
+ assign(__temp.data(), __temp.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::assign(_ForwardIterator __first, _ForwardIterator __last) {
+ if (__string_is_trivial_iterator<_ForwardIterator>::value) {
+ size_type __n = static_cast<size_type>(std::distance(__first, __last));
+ __assign_trivial(__first, __last, __n);
+ } else {
+ __assign_with_sentinel(__first, __last);
+ }
+
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+basic_string<_CharT, _Traits, _Allocator>::__assign_trivial(_Iterator __first, _Sentinel __last, size_type __n) {
+ _LIBCPP_ASSERT_INTERNAL(
+ __string_is_trivial_iterator<_Iterator>::value, "The iterator type given to `__assign_trivial` must be trivial");
+
+ size_type __old_size = size();
+ size_type __cap = capacity();
+ if (__cap < __n) {
+ // Unlike `append` functions, if the input range points into the string itself, there is no case that the input
+ // range could get invalidated by reallocation:
+ // 1. If the input range is a subset of the string itself, its size cannot exceed the capacity of the string,
+ // thus no reallocation would happen.
+ // 2. In the exotic case where the input range is the byte representation of the string itself, the string
+ // object itself stays valid even if reallocation happens.
+ size_type __sz = size();
+ __grow_by_without_replace(__cap, __n - __cap, __sz, 0, __sz);
+ __annotate_increase(__n);
+ } else if (__n > __old_size)
+ __annotate_increase(__n - __old_size);
+ pointer __p = __get_pointer();
+ for (; __first != __last; ++__p, (void)++__first)
+ traits_type::assign(*__p, *__first);
+ traits_type::assign(*__p, value_type());
+ __set_size(__n);
+ if (__n < __old_size)
+ __annotate_shrink(__old_size);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::assign(const basic_string& __str, size_type __pos, size_type __n) {
+ size_type __sz = __str.size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ return assign(__str.data() + __pos, std::min(__n, __sz - __pos));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string<_CharT, _Traits, _Allocator> >::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::assign(const _Tp& __t, size_type __pos, size_type __n) {
+ __self_view __sv = __t;
+ size_type __sz = __sv.size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ return assign(__sv.data() + __pos, std::min(__n, __sz - __pos));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::__assign_external(const value_type* __s) {
+ return __assign_external(__s, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s) {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::assign received nullptr");
+ return __builtin_constant_p(*__s)
+ ? (__fits_in_sso(traits_type::length(__s)) ? __assign_short(__s, traits_type::length(__s))
+ : __assign_external(__s, traits_type::length(__s)))
+ : __assign_external(__s);
+}
+// append
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s, size_type __n) {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::append received nullptr");
+ size_type __cap = capacity();
+ size_type __sz = size();
+ if (__cap - __sz >= __n) {
+ if (__n) {
+ __annotate_increase(__n);
+ value_type* __p = std::__to_address(__get_pointer());
+ traits_type::copy(__p + __sz, __s, __n);
+ __sz += __n;
+ __set_size(__sz);
+ traits_type::assign(__p[__sz], value_type());
+ }
+ } else
+ __grow_by_and_replace(__cap, __sz + __n - __cap, __sz, __sz, 0, __n, __s);
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::append(size_type __n, value_type __c) {
+ if (__n) {
+ size_type __cap = capacity();
+ size_type __sz = size();
+ if (__cap - __sz < __n)
+ __grow_by_without_replace(__cap, __sz + __n - __cap, __sz, __sz, 0);
+ __annotate_increase(__n);
+ pointer __p = __get_pointer();
+ traits_type::assign(std::__to_address(__p) + __sz, __n, __c);
+ __sz += __n;
+ __set_size(__sz);
+ traits_type::assign(__p[__sz], value_type());
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline void
+basic_string<_CharT, _Traits, _Allocator>::__append_default_init(size_type __n) {
+ if (__n) {
+ size_type __cap = capacity();
+ size_type __sz = size();
+ if (__cap - __sz < __n)
+ __grow_by_without_replace(__cap, __sz + __n - __cap, __sz, __sz, 0);
+ __annotate_increase(__n);
+ pointer __p = __get_pointer();
+ __sz += __n;
+ __set_size(__sz);
+ traits_type::assign(__p[__sz], value_type());
+ }
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::push_back(value_type __c) {
+ bool __is_short = !__is_long();
+ size_type __cap;
+ size_type __sz;
+ if (__is_short) {
+ __cap = __min_cap - 1;
+ __sz = __get_short_size();
+ } else {
+ __cap = __get_long_cap() - 1;
+ __sz = __get_long_size();
+ }
+ if (__sz == __cap) {
+ __grow_by_without_replace(__cap, 1, __sz, __sz, 0);
+ __annotate_increase(1);
+ __is_short = false; // the string is always long after __grow_by
+ } else
+ __annotate_increase(1);
+ pointer __p = __get_pointer();
+ if (__is_short) {
+ __p = __get_short_pointer() + __sz;
+ __set_short_size(__sz + 1);
+ } else {
+ __p = __get_long_pointer() + __sz;
+ __set_long_size(__sz + 1);
+ }
+ traits_type::assign(*__p, __c);
+ traits_type::assign(*++__p, value_type());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::append(_ForwardIterator __first, _ForwardIterator __last) {
+ size_type __sz = size();
+ size_type __cap = capacity();
+ size_type __n = static_cast<size_type>(std::distance(__first, __last));
+ if (__n) {
+ if (__string_is_trivial_iterator<_ForwardIterator>::value && !__addr_in_range(*__first)) {
+ if (__cap - __sz < __n)
+ __grow_by_without_replace(__cap, __sz + __n - __cap, __sz, __sz, 0);
+ __annotate_increase(__n);
+ auto __end = __copy_non_overlapping_range(__first, __last, std::__to_address(__get_pointer() + __sz));
+ traits_type::assign(*__end, value_type());
+ __set_size(__sz + __n);
+ } else {
+ const basic_string __temp(__first, __last, __alloc());
+ append(__temp.data(), __temp.size());
+ }
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::append(const basic_string& __str, size_type __pos, size_type __n) {
+ size_type __sz = __str.size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ return append(__str.data() + __pos, std::min(__n, __sz - __pos));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string<_CharT, _Traits, _Allocator> >::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::append(const _Tp& __t, size_type __pos, size_type __n) {
+ __self_view __sv = __t;
+ size_type __sz = __sv.size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ return append(__sv.data() + __pos, std::min(__n, __sz - __pos));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s) {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::append received nullptr");
+ return append(__s, traits_type::length(__s));
+}
+
+// insert
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s, size_type __n) {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::insert received nullptr");
+ size_type __sz = size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ size_type __cap = capacity();
+ if (__cap - __sz >= __n) {
+ if (__n) {
+ __annotate_increase(__n);
+ value_type* __p = std::__to_address(__get_pointer());
+ size_type __n_move = __sz - __pos;
+ if (__n_move != 0) {
+ if (std::__is_pointer_in_range(__p + __pos, __p + __sz, __s))
+ __s += __n;
+ traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
+ }
+ traits_type::move(__p + __pos, __s, __n);
+ __sz += __n;
+ __set_size(__sz);
+ traits_type::assign(__p[__sz], value_type());
+ }
+ } else
+ __grow_by_and_replace(__cap, __sz + __n - __cap, __sz, __pos, 0, __n, __s);
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, size_type __n, value_type __c) {
+ size_type __sz = size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ if (__n) {
+ size_type __cap = capacity();
+ value_type* __p;
+ if (__cap - __sz >= __n) {
+ __annotate_increase(__n);
+ __p = std::__to_address(__get_pointer());
+ size_type __n_move = __sz - __pos;
+ if (__n_move != 0)
+ traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
+ } else {
+ __grow_by_without_replace(__cap, __sz + __n - __cap, __sz, __pos, 0, __n);
+ __p = std::__to_address(__get_long_pointer());
+ }
+ traits_type::assign(__p + __pos, __n, __c);
+ __sz += __n;
+ __set_size(__sz);
+ traits_type::assign(__p[__sz], value_type());
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::iterator
+basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _InputIterator __first, _InputIterator __last) {
+ const basic_string __temp(__first, __last, __alloc());
+ return insert(__pos, __temp.data(), __temp.data() + __temp.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::iterator
+basic_string<_CharT, _Traits, _Allocator>::insert(
+ const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last) {
+ auto __n = static_cast<size_type>(std::distance(__first, __last));
+ return __insert_with_size(__pos, __first, __last, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::iterator
+basic_string<_CharT, _Traits, _Allocator>::__insert_with_size(
+ const_iterator __pos, _Iterator __first, _Sentinel __last, size_type __n) {
+ size_type __ip = static_cast<size_type>(__pos - begin());
+ if (__n == 0)
+ return begin() + __ip;
+
+ if (__string_is_trivial_iterator<_Iterator>::value && !__addr_in_range(*__first)) {
+ return __insert_from_safe_copy(__n, __ip, __first, __last);
+ } else {
+ const basic_string __temp(__init_with_sentinel_tag(), __first, __last, __alloc());
+ return __insert_from_safe_copy(__n, __ip, __temp.begin(), __temp.end());
+ }
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::insert(
+ size_type __pos1, const basic_string& __str, size_type __pos2, size_type __n) {
+ size_type __str_sz = __str.size();
+ if (__pos2 > __str_sz)
+ __throw_out_of_range();
+ return insert(__pos1, __str.data() + __pos2, std::min(__n, __str_sz - __pos2));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string<_CharT, _Traits, _Allocator> >::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const _Tp& __t, size_type __pos2, size_type __n) {
+ __self_view __sv = __t;
+ size_type __str_sz = __sv.size();
+ if (__pos2 > __str_sz)
+ __throw_out_of_range();
+ return insert(__pos1, __sv.data() + __pos2, std::min(__n, __str_sz - __pos2));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s) {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::insert received nullptr");
+ return insert(__pos, __s, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::iterator
+basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, value_type __c) {
+ size_type __ip = static_cast<size_type>(__pos - begin());
+ size_type __sz = size();
+ size_type __cap = capacity();
+ value_type* __p;
+ if (__cap == __sz) {
+ __grow_by_without_replace(__cap, 1, __sz, __ip, 0, 1);
+ __p = std::__to_address(__get_long_pointer());
+ } else {
+ __annotate_increase(1);
+ __p = std::__to_address(__get_pointer());
+ size_type __n_move = __sz - __ip;
+ if (__n_move != 0)
+ traits_type::move(__p + __ip + 1, __p + __ip, __n_move);
+ }
+ traits_type::assign(__p[__ip], __c);
+ traits_type::assign(__p[++__sz], value_type());
+ __set_size(__sz);
+ return begin() + static_cast<difference_type>(__ip);
+}
+
+// replace
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::replace(
+ size_type __pos, size_type __n1, const value_type* __s, size_type __n2)
+ _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK {
+ _LIBCPP_ASSERT_NON_NULL(__n2 == 0 || __s != nullptr, "string::replace received nullptr");
+ size_type __sz = size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ __n1 = std::min(__n1, __sz - __pos);
+ size_type __cap = capacity();
+ if (__cap - __sz + __n1 >= __n2) {
+ value_type* __p = std::__to_address(__get_pointer());
+ if (__n1 != __n2) {
+ if (__n2 > __n1)
+ __annotate_increase(__n2 - __n1);
+ size_type __n_move = __sz - __pos - __n1;
+ if (__n_move != 0) {
+ if (__n1 > __n2) {
+ traits_type::move(__p + __pos, __s, __n2);
+ traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
+ return __null_terminate_at(__p, __sz + (__n2 - __n1));
+ }
+ if (std::__is_pointer_in_range(__p + __pos + 1, __p + __sz, __s)) {
+ if (__p + __pos + __n1 <= __s)
+ __s += __n2 - __n1;
+ else // __p + __pos < __s < __p + __pos + __n1
+ {
+ traits_type::move(__p + __pos, __s, __n1);
+ __pos += __n1;
+ __s += __n2;
+ __n2 -= __n1;
+ __n1 = 0;
+ }
+ }
+ traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
+ }
+ }
+ traits_type::move(__p + __pos, __s, __n2);
+ return __null_terminate_at(__p, __sz + (__n2 - __n1));
+ } else
+ __grow_by_and_replace(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2, __s);
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, size_type __n2, value_type __c) {
+ size_type __sz = size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ __n1 = std::min(__n1, __sz - __pos);
+ size_type __cap = capacity();
+ value_type* __p;
+ if (__cap - __sz + __n1 >= __n2) {
+ __p = std::__to_address(__get_pointer());
+ if (__n1 != __n2) {
+ if (__n2 > __n1)
+ __annotate_increase(__n2 - __n1);
+ size_type __n_move = __sz - __pos - __n1;
+ if (__n_move != 0)
+ traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
+ }
+ } else {
+ __grow_by_without_replace(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2);
+ __p = std::__to_address(__get_long_pointer());
+ }
+ traits_type::assign(__p + __pos, __n2, __c);
+ return __null_terminate_at(__p, __sz - (__n1 - __n2));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::replace(
+ const_iterator __i1, const_iterator __i2, _InputIterator __j1, _InputIterator __j2) {
+ const basic_string __temp(__j1, __j2, __alloc());
+ return replace(__i1, __i2, __temp);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::replace(
+ size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2) {
+ size_type __str_sz = __str.size();
+ if (__pos2 > __str_sz)
+ __throw_out_of_range();
+ return replace(__pos1, __n1, __str.data() + __pos2, std::min(__n2, __str_sz - __pos2));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string<_CharT, _Traits, _Allocator> >::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::replace(
+ size_type __pos1, size_type __n1, const _Tp& __t, size_type __pos2, size_type __n2) {
+ __self_view __sv = __t;
+ size_type __str_sz = __sv.size();
+ if (__pos2 > __str_sz)
+ __throw_out_of_range();
+ return replace(__pos1, __n1, __sv.data() + __pos2, std::min(__n2, __str_sz - __pos2));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s) {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::replace received nullptr");
+ return replace(__pos, __n1, __s, traits_type::length(__s));
+}
+
+// erase
+
+// 'externally instantiated' erase() implementation, called when __n != npos.
+// Does not check __pos against size()
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_NOINLINE void
+basic_string<_CharT, _Traits, _Allocator>::__erase_external_with_move(size_type __pos, size_type __n) {
+ if (__n) {
+ size_type __sz = size();
+ value_type* __p = std::__to_address(__get_pointer());
+ __n = std::min(__n, __sz - __pos);
+ size_type __n_move = __sz - __pos - __n;
+ if (__n_move != 0)
+ traits_type::move(__p + __pos, __p + __pos + __n, __n_move);
+ __null_terminate_at(__p, __sz - __n);
+ }
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>&
+basic_string<_CharT, _Traits, _Allocator>::erase(size_type __pos, size_type __n) {
+ if (__pos > size())
+ __throw_out_of_range();
+ if (__n == npos) {
+ __erase_to_end(__pos);
+ } else {
+ __erase_external_with_move(__pos, __n);
+ }
+ return *this;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::iterator
+basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __pos) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __pos != end(), "string::erase(iterator) called with a non-dereferenceable iterator");
+ iterator __b = begin();
+ size_type __r = static_cast<size_type>(__pos - __b);
+ erase(__r, 1);
+ return __b + static_cast<difference_type>(__r);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::iterator
+basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __first, const_iterator __last) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__first <= __last, "string::erase(first, last) called with invalid range");
+ iterator __b = begin();
+ size_type __r = static_cast<size_type>(__first - __b);
+ erase(__r, static_cast<size_type>(__last - __first));
+ return __b + static_cast<difference_type>(__r);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::pop_back() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "string::pop_back(): string is already empty");
+ __erase_to_end(size() - 1);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::clear() _NOEXCEPT {
+ size_type __old_size = size();
+ if (__is_long()) {
+ traits_type::assign(*__get_long_pointer(), value_type());
+ __set_long_size(0);
+ } else {
+ traits_type::assign(*__get_short_pointer(), value_type());
+ __set_short_size(0);
+ }
+ __annotate_shrink(__old_size);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::resize(size_type __n, value_type __c) {
+ size_type __sz = size();
+ if (__n > __sz)
+ append(__n - __sz, __c);
+ else
+ __erase_to_end(__n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline void
+basic_string<_CharT, _Traits, _Allocator>::__resize_default_init(size_type __n) {
+ size_type __sz = size();
+ if (__n > __sz) {
+ __append_default_init(__n - __sz);
+ } else
+ __erase_to_end(__n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::reserve(size_type __requested_capacity) {
+ if (__requested_capacity > max_size())
+ __throw_length_error();
+
+ // Make sure reserve(n) never shrinks. This is technically only required in C++20
+ // and later (since P0966R1), however we provide consistent behavior in all Standard
+ // modes because this function is instantiated in the shared library.
+ if (__requested_capacity <= capacity())
+ return;
+
+ size_type __target_capacity = std::max(__requested_capacity, size());
+ __target_capacity = __recommend(__target_capacity);
+ if (__target_capacity == capacity())
+ return;
+
+ __shrink_or_extend(__target_capacity);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::shrink_to_fit() _NOEXCEPT {
+ size_type __target_capacity = __recommend(size());
+ if (__target_capacity == capacity())
+ return;
+
+ __shrink_or_extend(__target_capacity);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+basic_string<_CharT, _Traits, _Allocator>::__shrink_or_extend(size_type __target_capacity) {
+ __annotate_delete();
+ size_type __cap = capacity();
+ size_type __sz = size();
+
+ pointer __new_data, __p;
+ bool __was_long, __now_long;
+ if (__fits_in_sso(__target_capacity)) {
+ __was_long = true;
+ __now_long = false;
+ __new_data = __get_short_pointer();
+ __p = __get_long_pointer();
+ } else {
+ if (__target_capacity > __cap) {
+ // Extend
+ // - called from reserve should propagate the exception thrown.
+ auto __allocation = std::__allocate_at_least(__alloc(), __target_capacity + 1);
+ __new_data = __allocation.ptr;
+ __target_capacity = __allocation.count - 1;
+ } else {
+ // Shrink
+ // - called from shrink_to_fit should not throw.
+ // - called from reserve may throw but is not required to.
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ auto __allocation = std::__allocate_at_least(__alloc(), __target_capacity + 1);
+
+ // The Standard mandates shrink_to_fit() does not increase the capacity.
+ // With equal capacity keep the existing buffer. This avoids extra work
+ // due to swapping the elements.
+ if (__allocation.count - 1 > __target_capacity) {
+ __alloc_traits::deallocate(__alloc(), __allocation.ptr, __allocation.count);
+ __annotate_new(__sz); // Undoes the __annotate_delete()
+ return;
+ }
+ __new_data = __allocation.ptr;
+ __target_capacity = __allocation.count - 1;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ return;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+ __begin_lifetime(__new_data, __target_capacity + 1);
+ __now_long = true;
+ __was_long = __is_long();
+ __p = __get_pointer();
+ }
+ traits_type::copy(std::__to_address(__new_data), std::__to_address(__p), size() + 1);
+ if (__was_long)
+ __alloc_traits::deallocate(__alloc(), __p, __cap + 1);
+ if (__now_long) {
+ __set_long_cap(__target_capacity + 1);
+ __set_long_size(__sz);
+ __set_long_pointer(__new_data);
+ } else
+ __set_short_size(__sz);
+ __annotate_new(__sz);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::const_reference
+basic_string<_CharT, _Traits, _Allocator>::at(size_type __n) const {
+ if (__n >= size())
+ __throw_out_of_range();
+ return (*this)[__n];
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::reference
+basic_string<_CharT, _Traits, _Allocator>::at(size_type __n) {
+ if (__n >= size())
+ __throw_out_of_range();
+ return (*this)[__n];
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::copy(value_type* __s, size_type __n, size_type __pos) const {
+ size_type __sz = size();
+ if (__pos > __sz)
+ __throw_out_of_range();
+ size_type __rlen = std::min(__n, __sz - __pos);
+ traits_type::copy(__s, data() + __pos, __rlen);
+ return __rlen;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::swap(basic_string& __str)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>)
+#endif
+{
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __alloc_traits::propagate_on_container_swap::value || __alloc_traits::is_always_equal::value ||
+ __alloc() == __str.__alloc(),
+ "swapping non-equal allocators");
+ if (!__is_long())
+ __annotate_delete();
+ if (this != &__str && !__str.__is_long())
+ __str.__annotate_delete();
+ std::swap(__r_.first(), __str.__r_.first());
+ std::__swap_allocator(__alloc(), __str.__alloc());
+ if (!__is_long())
+ __annotate_new(__get_short_size());
+ if (this != &__str && !__str.__is_long())
+ __str.__annotate_new(__str.__get_short_size());
+}
+
+// find
+
+template <class _Traits>
+struct _LIBCPP_HIDDEN __traits_eq {
+ typedef typename _Traits::char_type char_type;
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const char_type& __x, const char_type& __y) _NOEXCEPT {
+ return _Traits::eq(__x, __y);
+ }
+};
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::find(): received nullptr");
+ return std::__str_find<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find(const basic_string& __str, size_type __pos) const _NOEXCEPT {
+ return std::__str_find<value_type, size_type, traits_type, npos>(data(), size(), __str.data(), __pos, __str.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find(const _Tp& __t, size_type __pos) const _NOEXCEPT {
+ __self_view __sv = __t;
+ return std::__str_find<value_type, size_type, traits_type, npos>(data(), size(), __sv.data(), __pos, __sv.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s, size_type __pos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::find(): received nullptr");
+ return std::__str_find<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find(value_type __c, size_type __pos) const _NOEXCEPT {
+ return std::__str_find<value_type, size_type, traits_type, npos>(data(), size(), __c, __pos);
+}
+
+// rfind
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::rfind(
+ const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::rfind(): received nullptr");
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::rfind(const basic_string& __str, size_type __pos) const _NOEXCEPT {
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(data(), size(), __str.data(), __pos, __str.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::rfind(const _Tp& __t, size_type __pos) const _NOEXCEPT {
+ __self_view __sv = __t;
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(data(), size(), __sv.data(), __pos, __sv.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s, size_type __pos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::rfind(): received nullptr");
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::rfind(value_type __c, size_type __pos) const _NOEXCEPT {
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(data(), size(), __c, __pos);
+}
+
+// find_first_of
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_of(
+ const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::find_first_of(): received nullptr");
+ return std::__str_find_first_of<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_of(const basic_string& __str, size_type __pos) const _NOEXCEPT {
+ return std::__str_find_first_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __str.data(), __pos, __str.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_of(const _Tp& __t, size_type __pos) const _NOEXCEPT {
+ __self_view __sv = __t;
+ return std::__str_find_first_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __sv.data(), __pos, __sv.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s, size_type __pos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::find_first_of(): received nullptr");
+ return std::__str_find_first_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_of(value_type __c, size_type __pos) const _NOEXCEPT {
+ return find(__c, __pos);
+}
+
+// find_last_of
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_of(
+ const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::find_last_of(): received nullptr");
+ return std::__str_find_last_of<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_of(const basic_string& __str, size_type __pos) const _NOEXCEPT {
+ return std::__str_find_last_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __str.data(), __pos, __str.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_of(const _Tp& __t, size_type __pos) const _NOEXCEPT {
+ __self_view __sv = __t;
+ return std::__str_find_last_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __sv.data(), __pos, __sv.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s, size_type __pos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::find_last_of(): received nullptr");
+ return std::__str_find_last_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_of(value_type __c, size_type __pos) const _NOEXCEPT {
+ return rfind(__c, __pos);
+}
+
+// find_first_not_of
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(
+ const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::find_first_not_of(): received nullptr");
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(
+ const basic_string& __str, size_type __pos) const _NOEXCEPT {
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __str.data(), __pos, __str.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const _Tp& __t, size_type __pos) const _NOEXCEPT {
+ __self_view __sv = __t;
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __sv.data(), __pos, __sv.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s, size_type __pos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::find_first_not_of(): received nullptr");
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(value_type __c, size_type __pos) const _NOEXCEPT {
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(data(), size(), __c, __pos);
+}
+
+// find_last_not_of
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(
+ const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string::find_last_not_of(): received nullptr");
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(
+ const basic_string& __str, size_type __pos) const _NOEXCEPT {
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __str.data(), __pos, __str.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const _Tp& __t, size_type __pos) const _NOEXCEPT {
+ __self_view __sv = __t;
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __sv.data(), __pos, __sv.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s, size_type __pos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::find_last_not_of(): received nullptr");
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::size_type
+basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(value_type __c, size_type __pos) const _NOEXCEPT {
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(data(), size(), __c, __pos);
+}
+
+// compare
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 int basic_string<_CharT, _Traits, _Allocator>::compare(const _Tp& __t) const _NOEXCEPT {
+ __self_view __sv = __t;
+ size_t __lhs_sz = size();
+ size_t __rhs_sz = __sv.size();
+ int __result = traits_type::compare(data(), __sv.data(), std::min(__lhs_sz, __rhs_sz));
+ if (__result != 0)
+ return __result;
+ if (__lhs_sz < __rhs_sz)
+ return -1;
+ if (__lhs_sz > __rhs_sz)
+ return 1;
+ return 0;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 int
+basic_string<_CharT, _Traits, _Allocator>::compare(const basic_string& __str) const _NOEXCEPT {
+ return compare(__self_view(__str));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 int basic_string<_CharT, _Traits, _Allocator>::compare(
+ size_type __pos1, size_type __n1, const value_type* __s, size_type __n2) const {
+ _LIBCPP_ASSERT_NON_NULL(__n2 == 0 || __s != nullptr, "string::compare(): received nullptr");
+ size_type __sz = size();
+ if (__pos1 > __sz || __n2 == npos)
+ __throw_out_of_range();
+ size_type __rlen = std::min(__n1, __sz - __pos1);
+ int __r = traits_type::compare(data() + __pos1, __s, std::min(__rlen, __n2));
+ if (__r == 0) {
+ if (__rlen < __n2)
+ __r = -1;
+ else if (__rlen > __n2)
+ __r = 1;
+ }
+ return __r;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp, __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 int
+basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1, size_type __n1, const _Tp& __t) const {
+ __self_view __sv = __t;
+ return compare(__pos1, __n1, __sv.data(), __sv.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 int
+basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1, size_type __n1, const basic_string& __str) const {
+ return compare(__pos1, __n1, __str.data(), __str.size());
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+template <class _Tp,
+ __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
+ !__is_same_uncvref<_Tp, basic_string<_CharT, _Traits, _Allocator> >::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 int basic_string<_CharT, _Traits, _Allocator>::compare(
+ size_type __pos1, size_type __n1, const _Tp& __t, size_type __pos2, size_type __n2) const {
+ __self_view __sv = __t;
+ return __self_view(*this).substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 int basic_string<_CharT, _Traits, _Allocator>::compare(
+ size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2) const {
+ return compare(__pos1, __n1, __self_view(__str), __pos2, __n2);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 int
+basic_string<_CharT, _Traits, _Allocator>::compare(const value_type* __s) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::compare(): received nullptr");
+ return compare(0, npos, __s, traits_type::length(__s));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 int
+basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1, size_type __n1, const value_type* __s) const {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string::compare(): received nullptr");
+ return compare(__pos1, __n1, __s, traits_type::length(__s));
+}
+
+// __invariants
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 bool basic_string<_CharT, _Traits, _Allocator>::__invariants() const {
+ if (size() > capacity())
+ return false;
+ if (capacity() < __min_cap - 1)
+ return false;
+ if (data() == nullptr)
+ return false;
+ if (!_Traits::eq(data()[size()], value_type()))
+ return false;
+ return true;
+}
+
+// __clear_and_shrink
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 void basic_string<_CharT, _Traits, _Allocator>::__clear_and_shrink() _NOEXCEPT {
+ clear();
+ if (__is_long()) {
+ __annotate_delete();
+ __alloc_traits::deallocate(__alloc(), __get_long_pointer(), capacity() + 1);
+ __r_.first() = __rep();
+ }
+}
+
+// operator==
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool
+operator==(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+#if _LIBCPP_STD_VER >= 20
+ return basic_string_view<_CharT, _Traits>(__lhs) == basic_string_view<_CharT, _Traits>(__rhs);
+#else
+ size_t __lhs_sz = __lhs.size();
+ return __lhs_sz == __rhs.size() && _Traits::compare(__lhs.data(), __rhs.data(), __lhs_sz) == 0;
+#endif
+}
+
+template <class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool
+operator==(const basic_string<char, char_traits<char>, _Allocator>& __lhs,
+ const basic_string<char, char_traits<char>, _Allocator>& __rhs) _NOEXCEPT {
+ size_t __sz = __lhs.size();
+ if (__sz != __rhs.size())
+ return false;
+ return char_traits<char>::compare(__lhs.data(), __rhs.data(), __sz) == 0;
+}
+
+#if _LIBCPP_STD_VER <= 17
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const _CharT* __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ typedef basic_string<_CharT, _Traits, _Allocator> _String;
+ _LIBCPP_ASSERT_NON_NULL(__lhs != nullptr, "operator==(char*, basic_string): received nullptr");
+ size_t __lhs_len = _Traits::length(__lhs);
+ if (__lhs_len != __rhs.size())
+ return false;
+ return __rhs.compare(0, _String::npos, __lhs, __lhs_len) == 0;
+}
+#endif // _LIBCPP_STD_VER <= 17
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool
+operator==(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs) _NOEXCEPT {
+#if _LIBCPP_STD_VER >= 20
+ return basic_string_view<_CharT, _Traits>(__lhs) == basic_string_view<_CharT, _Traits>(__rhs);
+#else
+ typedef basic_string<_CharT, _Traits, _Allocator> _String;
+ _LIBCPP_ASSERT_NON_NULL(__rhs != nullptr, "operator==(basic_string, char*): received nullptr");
+ size_t __rhs_len = _Traits::length(__rhs);
+ if (__rhs_len != __lhs.size())
+ return false;
+ return __lhs.compare(0, _String::npos, __rhs, __rhs_len) == 0;
+#endif
+}
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr auto operator<=>(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) noexcept {
+ return basic_string_view<_CharT, _Traits>(__lhs) <=> basic_string_view<_CharT, _Traits>(__rhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+operator<=>(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs) {
+ return basic_string_view<_CharT, _Traits>(__lhs) <=> basic_string_view<_CharT, _Traits>(__rhs);
+}
+
+#else // _LIBCPP_STD_VER >= 20
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return !(__lhs == __rhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const _CharT* __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return !(__lhs == __rhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs) _NOEXCEPT {
+ return !(__lhs == __rhs);
+}
+
+// operator<
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) < 0;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) < 0;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<(const _CharT* __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return __rhs.compare(__lhs) > 0;
+}
+
+// operator>
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return __rhs < __lhs;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs) _NOEXCEPT {
+ return __rhs < __lhs;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>(const _CharT* __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return __rhs < __lhs;
+}
+
+// operator<=
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return !(__rhs < __lhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs) _NOEXCEPT {
+ return !(__rhs < __lhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator<=(const _CharT* __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return !(__rhs < __lhs);
+}
+
+// operator>=
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return !(__lhs < __rhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs) _NOEXCEPT {
+ return !(__lhs < __rhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator>=(const _CharT* __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT {
+ return !(__lhs < __rhs);
+}
+#endif // _LIBCPP_STD_VER >= 20
+
+// operator +
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) {
+ using _String = basic_string<_CharT, _Traits, _Allocator>;
+ auto __lhs_sz = __lhs.size();
+ auto __rhs_sz = __rhs.size();
+ _String __r(__uninitialized_size_tag(),
+ __lhs_sz + __rhs_sz,
+ _String::__alloc_traits::select_on_container_copy_construction(__lhs.get_allocator()));
+ auto __ptr = std::__to_address(__r.__get_pointer());
+ _Traits::copy(__ptr, __lhs.data(), __lhs_sz);
+ _Traits::copy(__ptr + __lhs_sz, __rhs.data(), __rhs_sz);
+ _Traits::assign(__ptr + __lhs_sz + __rhs_sz, 1, _CharT());
+ return __r;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDDEN _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const _CharT* __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) {
+ using _String = basic_string<_CharT, _Traits, _Allocator>;
+ auto __lhs_sz = _Traits::length(__lhs);
+ auto __rhs_sz = __rhs.size();
+ _String __r(__uninitialized_size_tag(),
+ __lhs_sz + __rhs_sz,
+ _String::__alloc_traits::select_on_container_copy_construction(__rhs.get_allocator()));
+ auto __ptr = std::__to_address(__r.__get_pointer());
+ _Traits::copy(__ptr, __lhs, __lhs_sz);
+ _Traits::copy(__ptr + __lhs_sz, __rhs.data(), __rhs_sz);
+ _Traits::assign(__ptr + __lhs_sz + __rhs_sz, 1, _CharT());
+ return __r;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(_CharT __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) {
+ using _String = basic_string<_CharT, _Traits, _Allocator>;
+ typename _String::size_type __rhs_sz = __rhs.size();
+ _String __r(__uninitialized_size_tag(),
+ __rhs_sz + 1,
+ _String::__alloc_traits::select_on_container_copy_construction(__rhs.get_allocator()));
+ auto __ptr = std::__to_address(__r.__get_pointer());
+ _Traits::assign(__ptr, 1, __lhs);
+ _Traits::copy(__ptr + 1, __rhs.data(), __rhs_sz);
+ _Traits::assign(__ptr + 1 + __rhs_sz, 1, _CharT());
+ return __r;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs) {
+ using _String = basic_string<_CharT, _Traits, _Allocator>;
+ typename _String::size_type __lhs_sz = __lhs.size();
+ typename _String::size_type __rhs_sz = _Traits::length(__rhs);
+ _String __r(__uninitialized_size_tag(),
+ __lhs_sz + __rhs_sz,
+ _String::__alloc_traits::select_on_container_copy_construction(__lhs.get_allocator()));
+ auto __ptr = std::__to_address(__r.__get_pointer());
+ _Traits::copy(__ptr, __lhs.data(), __lhs_sz);
+ _Traits::copy(__ptr + __lhs_sz, __rhs, __rhs_sz);
+ _Traits::assign(__ptr + __lhs_sz + __rhs_sz, 1, _CharT());
+ return __r;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, _CharT __rhs) {
+ using _String = basic_string<_CharT, _Traits, _Allocator>;
+ typename _String::size_type __lhs_sz = __lhs.size();
+ _String __r(__uninitialized_size_tag(),
+ __lhs_sz + 1,
+ _String::__alloc_traits::select_on_container_copy_construction(__lhs.get_allocator()));
+ auto __ptr = std::__to_address(__r.__get_pointer());
+ _Traits::copy(__ptr, __lhs.data(), __lhs_sz);
+ _Traits::assign(__ptr + __lhs_sz, 1, __rhs);
+ _Traits::assign(__ptr + 1 + __lhs_sz, 1, _CharT());
+ return __r;
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs) {
+ return std::move(__lhs.append(__rhs));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs) {
+ return std::move(__rhs.insert(0, __lhs));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs) {
+ return std::move(__lhs.append(__rhs));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(const _CharT* __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs) {
+ return std::move(__rhs.insert(0, __lhs));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(_CharT __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs) {
+ __rhs.insert(__rhs.begin(), __lhs);
+ return std::move(__rhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, const _CharT* __rhs) {
+ return std::move(__lhs.append(__rhs));
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<_CharT, _Traits, _Allocator>
+operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, _CharT __rhs) {
+ __lhs.push_back(__rhs);
+ return std::move(__lhs);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 26
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr basic_string<_CharT, _Traits, _Allocator>
+operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
+ type_identity_t<basic_string_view<_CharT, _Traits>> __rhs) {
+ using _String = basic_string<_CharT, _Traits, _Allocator>;
+ typename _String::size_type __lhs_sz = __lhs.size();
+ typename _String::size_type __rhs_sz = __rhs.size();
+ _String __r(__uninitialized_size_tag(),
+ __lhs_sz + __rhs_sz,
+ _String::__alloc_traits::select_on_container_copy_construction(__lhs.get_allocator()));
+ auto __ptr = std::__to_address(__r.__get_pointer());
+ _Traits::copy(__ptr, __lhs.data(), __lhs_sz);
+ _Traits::copy(__ptr + __lhs_sz, __rhs.data(), __rhs_sz);
+ _Traits::assign(__ptr + __lhs_sz + __rhs_sz, 1, _CharT());
+ return __r;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr basic_string<_CharT, _Traits, _Allocator>
+operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs,
+ type_identity_t<basic_string_view<_CharT, _Traits>> __rhs) {
+ __lhs.append(__rhs);
+ return std::move(__lhs);
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr basic_string<_CharT, _Traits, _Allocator>
+operator+(type_identity_t<basic_string_view<_CharT, _Traits>> __lhs,
+ const basic_string<_CharT, _Traits, _Allocator>& __rhs) {
+ using _String = basic_string<_CharT, _Traits, _Allocator>;
+ typename _String::size_type __lhs_sz = __lhs.size();
+ typename _String::size_type __rhs_sz = __rhs.size();
+ _String __r(__uninitialized_size_tag(),
+ __lhs_sz + __rhs_sz,
+ _String::__alloc_traits::select_on_container_copy_construction(__rhs.get_allocator()));
+ auto __ptr = std::__to_address(__r.__get_pointer());
+ _Traits::copy(__ptr, __lhs.data(), __lhs_sz);
+ _Traits::copy(__ptr + __lhs_sz, __rhs.data(), __rhs_sz);
+ _Traits::assign(__ptr + __lhs_sz + __rhs_sz, 1, _CharT());
+ return __r;
+}
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr basic_string<_CharT, _Traits, _Allocator>
+operator+(type_identity_t<basic_string_view<_CharT, _Traits>> __lhs,
+ basic_string<_CharT, _Traits, _Allocator>&& __rhs) {
+ __rhs.insert(0, __lhs);
+ return std::move(__rhs);
+}
+
+#endif // _LIBCPP_STD_VER >= 26
+
+// swap
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+swap(basic_string<_CharT, _Traits, _Allocator>& __lhs, basic_string<_CharT, _Traits, _Allocator>& __rhs)
+ _NOEXCEPT_(_NOEXCEPT_(__lhs.swap(__rhs))) {
+ __lhs.swap(__rhs);
+}
+
+_LIBCPP_EXPORTED_FROM_ABI int stoi(const string& __str, size_t* __idx = nullptr, int __base = 10);
+_LIBCPP_EXPORTED_FROM_ABI long stol(const string& __str, size_t* __idx = nullptr, int __base = 10);
+_LIBCPP_EXPORTED_FROM_ABI unsigned long stoul(const string& __str, size_t* __idx = nullptr, int __base = 10);
+_LIBCPP_EXPORTED_FROM_ABI long long stoll(const string& __str, size_t* __idx = nullptr, int __base = 10);
+_LIBCPP_EXPORTED_FROM_ABI unsigned long long stoull(const string& __str, size_t* __idx = nullptr, int __base = 10);
+
+_LIBCPP_EXPORTED_FROM_ABI float stof(const string& __str, size_t* __idx = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI double stod(const string& __str, size_t* __idx = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI long double stold(const string& __str, size_t* __idx = nullptr);
+
+_LIBCPP_EXPORTED_FROM_ABI string to_string(int __val);
+_LIBCPP_EXPORTED_FROM_ABI string to_string(unsigned __val);
+_LIBCPP_EXPORTED_FROM_ABI string to_string(long __val);
+_LIBCPP_EXPORTED_FROM_ABI string to_string(unsigned long __val);
+_LIBCPP_EXPORTED_FROM_ABI string to_string(long long __val);
+_LIBCPP_EXPORTED_FROM_ABI string to_string(unsigned long long __val);
+_LIBCPP_EXPORTED_FROM_ABI string to_string(float __val);
+_LIBCPP_EXPORTED_FROM_ABI string to_string(double __val);
+_LIBCPP_EXPORTED_FROM_ABI string to_string(long double __val);
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+_LIBCPP_EXPORTED_FROM_ABI int stoi(const wstring& __str, size_t* __idx = nullptr, int __base = 10);
+_LIBCPP_EXPORTED_FROM_ABI long stol(const wstring& __str, size_t* __idx = nullptr, int __base = 10);
+_LIBCPP_EXPORTED_FROM_ABI unsigned long stoul(const wstring& __str, size_t* __idx = nullptr, int __base = 10);
+_LIBCPP_EXPORTED_FROM_ABI long long stoll(const wstring& __str, size_t* __idx = nullptr, int __base = 10);
+_LIBCPP_EXPORTED_FROM_ABI unsigned long long stoull(const wstring& __str, size_t* __idx = nullptr, int __base = 10);
+
+_LIBCPP_EXPORTED_FROM_ABI float stof(const wstring& __str, size_t* __idx = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI double stod(const wstring& __str, size_t* __idx = nullptr);
+_LIBCPP_EXPORTED_FROM_ABI long double stold(const wstring& __str, size_t* __idx = nullptr);
+
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(int __val);
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(unsigned __val);
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(long __val);
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(unsigned long __val);
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(long long __val);
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(unsigned long long __val);
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(float __val);
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(double __val);
+_LIBCPP_EXPORTED_FROM_ABI wstring to_wstring(long double __val);
+#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_TEMPLATE_DATA_VIS const typename basic_string<_CharT, _Traits, _Allocator>::size_type
+ basic_string<_CharT, _Traits, _Allocator>::npos;
+
+template <class _CharT, class _Allocator>
+struct __string_hash : public __unary_function<basic_string<_CharT, char_traits<_CharT>, _Allocator>, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t
+ operator()(const basic_string<_CharT, char_traits<_CharT>, _Allocator>& __val) const _NOEXCEPT {
+ return std::__do_string_hash(__val.data(), __val.data() + __val.size());
+ }
+};
+
+template <class _Allocator>
+struct hash<basic_string<char, char_traits<char>, _Allocator> > : __string_hash<char, _Allocator> {};
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <class _Allocator>
+struct hash<basic_string<char8_t, char_traits<char8_t>, _Allocator> > : __string_hash<char8_t, _Allocator> {};
+#endif
+
+template <class _Allocator>
+struct hash<basic_string<char16_t, char_traits<char16_t>, _Allocator> > : __string_hash<char16_t, _Allocator> {};
+
+template <class _Allocator>
+struct hash<basic_string<char32_t, char_traits<char32_t>, _Allocator> > : __string_hash<char32_t, _Allocator> {};
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <class _Allocator>
+struct hash<basic_string<wchar_t, char_traits<wchar_t>, _Allocator> > : __string_hash<wchar_t, _Allocator> {};
+#endif
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const basic_string<_CharT, _Traits, _Allocator>& __str);
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, basic_string<_CharT, _Traits, _Allocator>& __str);
+
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+getline(basic_istream<_CharT, _Traits>& __is, basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm);
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+getline(basic_istream<_CharT, _Traits>& __is, basic_string<_CharT, _Traits, _Allocator>& __str);
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+getline(basic_istream<_CharT, _Traits>&& __is, basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm);
+
+template <class _CharT, class _Traits, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+getline(basic_istream<_CharT, _Traits>&& __is, basic_string<_CharT, _Traits, _Allocator>& __str);
+
+#if _LIBCPP_STD_VER >= 20
+template <class _CharT, class _Traits, class _Allocator, class _Up>
+inline _LIBCPP_HIDE_FROM_ABI typename basic_string<_CharT, _Traits, _Allocator>::size_type
+erase(basic_string<_CharT, _Traits, _Allocator>& __str, const _Up& __v) {
+ auto __old_size = __str.size();
+ __str.erase(std::remove(__str.begin(), __str.end(), __v), __str.end());
+ return __old_size - __str.size();
+}
+
+template <class _CharT, class _Traits, class _Allocator, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename basic_string<_CharT, _Traits, _Allocator>::size_type
+erase_if(basic_string<_CharT, _Traits, _Allocator>& __str, _Predicate __pred) {
+ auto __old_size = __str.size();
+ __str.erase(std::remove_if(__str.begin(), __str.end(), __pred), __str.end());
+ return __old_size - __str.size();
+}
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+// Literal suffixes for basic_string [basic.string.literals]
+inline namespace literals {
+inline namespace string_literals {
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<char>
+operator""s(const char* __str, size_t __len) {
+ return basic_string<char>(__str, __len);
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<wchar_t>
+operator""s(const wchar_t* __str, size_t __len) {
+ return basic_string<wchar_t>(__str, __len);
+}
+# endif
+
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+inline _LIBCPP_HIDE_FROM_ABI constexpr basic_string<char8_t> operator""s(const char8_t* __str, size_t __len) {
+ return basic_string<char8_t>(__str, __len);
+}
+# endif
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<char16_t>
+operator""s(const char16_t* __str, size_t __len) {
+ return basic_string<char16_t>(__str, __len);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string<char32_t>
+operator""s(const char32_t* __str, size_t __len) {
+ return basic_string<char32_t>(__str, __len);
+}
+} // namespace string_literals
+} // namespace literals
+
+# if _LIBCPP_STD_VER >= 20
+template <>
+inline constexpr bool __format::__enable_insertable<std::basic_string<char>> = true;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+inline constexpr bool __format::__enable_insertable<std::basic_string<wchar_t>> = true;
+# endif
+# endif
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <concepts>
+# include <cstdlib>
+# include <iterator>
+# include <new>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_STRING
diff --git a/libcxx/include/__cxx03/string.h b/libcxx/include/__cxx03/string.h
new file mode 100644
index 00000000000000..ae10d5ad2c76f1
--- /dev/null
+++ b/libcxx/include/__cxx03/string.h
@@ -0,0 +1,110 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STRING_H
+#define _LIBCPP_STRING_H
+
+/*
+ string.h synopsis
+
+Macros:
+
+ NULL
+
+Types:
+
+ size_t
+
+void* memcpy(void* restrict s1, const void* restrict s2, size_t n);
+void* memmove(void* s1, const void* s2, size_t n);
+char* strcpy (char* restrict s1, const char* restrict s2);
+char* strncpy(char* restrict s1, const char* restrict s2, size_t n);
+char* strcat (char* restrict s1, const char* restrict s2);
+char* strncat(char* restrict s1, const char* restrict s2, size_t n);
+int memcmp(const void* s1, const void* s2, size_t n);
+int strcmp (const char* s1, const char* s2);
+int strncmp(const char* s1, const char* s2, size_t n);
+int strcoll(const char* s1, const char* s2);
+size_t strxfrm(char* restrict s1, const char* restrict s2, size_t n);
+const void* memchr(const void* s, int c, size_t n);
+ void* memchr( void* s, int c, size_t n);
+const char* strchr(const char* s, int c);
+ char* strchr( char* s, int c);
+size_t strcspn(const char* s1, const char* s2);
+const char* strpbrk(const char* s1, const char* s2);
+ char* strpbrk( char* s1, const char* s2);
+const char* strrchr(const char* s, int c);
+ char* strrchr( char* s, int c);
+size_t strspn(const char* s1, const char* s2);
+const char* strstr(const char* s1, const char* s2);
+ char* strstr( char* s1, const char* s2);
+char* strtok(char* restrict s1, const char* restrict s2);
+void* memset(void* s, int c, size_t n);
+char* strerror(int errnum);
+size_t strlen(const char* s);
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if __has_include_next(<string.h>)
+# include_next <string.h>
+#endif
+
+// MSVCRT, GNU libc and its derivates may already have the correct prototype in
+// <string.h>. This macro can be defined by users if their C library provides
+// the right signature.
+#if defined(__CORRECT_ISO_CPP_STRING_H_PROTO) || defined(_LIBCPP_MSVCRT) || defined(_STRING_H_CPLUSPLUS_98_CONFORMANCE_)
+# define _LIBCPP_STRING_H_HAS_CONST_OVERLOADS
+#endif
+
+#if defined(__cplusplus) && !defined(_LIBCPP_STRING_H_HAS_CONST_OVERLOADS) && defined(_LIBCPP_PREFERRED_OVERLOAD)
+extern "C++" {
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const char* strchr(const char* __s, int __c) {
+ return __builtin_strchr(__s, __c);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD char* strchr(char* __s, int __c) {
+ return __builtin_strchr(__s, __c);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const char* strpbrk(const char* __s1, const char* __s2) {
+ return __builtin_strpbrk(__s1, __s2);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD char* strpbrk(char* __s1, const char* __s2) {
+ return __builtin_strpbrk(__s1, __s2);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const char* strrchr(const char* __s, int __c) {
+ return __builtin_strrchr(__s, __c);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD char* strrchr(char* __s, int __c) {
+ return __builtin_strrchr(__s, __c);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const void* memchr(const void* __s, int __c, size_t __n) {
+ return __builtin_memchr(__s, __c, __n);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD void* memchr(void* __s, int __c, size_t __n) {
+ return __builtin_memchr(__s, __c, __n);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const char* strstr(const char* __s1, const char* __s2) {
+ return __builtin_strstr(__s1, __s2);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD char* strstr(char* __s1, const char* __s2) {
+ return __builtin_strstr(__s1, __s2);
+}
+} // extern "C++"
+#endif
+
+#endif // _LIBCPP_STRING_H
diff --git a/libcxx/include/__cxx03/string_view b/libcxx/include/__cxx03/string_view
new file mode 100644
index 00000000000000..72dbf0bfa8e540
--- /dev/null
+++ b/libcxx/include/__cxx03/string_view
@@ -0,0 +1,948 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STRING_VIEW
+#define _LIBCPP_STRING_VIEW
+
+// clang-format off
+
+/*
+
+ string_view synopsis
+
+#include <compare>
+
+namespace std {
+
+ // 7.2, Class template basic_string_view
+ template<class charT, class traits = char_traits<charT>>
+ class basic_string_view;
+
+ template<class charT, class traits>
+ inline constexpr bool ranges::enable_view<basic_string_view<charT, traits>> = true;
+
+ template<class charT, class traits>
+ inline constexpr bool ranges::enable_borrowed_range<basic_string_view<charT, traits>> = true; // C++20
+
+ // 7.9, basic_string_view non-member comparison functions
+ template<class charT, class traits>
+ constexpr bool operator==(basic_string_view<charT, traits> x,
+ basic_string_view<charT, traits> y) noexcept;
+ template<class charT, class traits> // Removed in C++20
+ constexpr bool operator!=(basic_string_view<charT, traits> x,
+ basic_string_view<charT, traits> y) noexcept;
+ template<class charT, class traits> // Removed in C++20
+ constexpr bool operator< (basic_string_view<charT, traits> x,
+ basic_string_view<charT, traits> y) noexcept;
+ template<class charT, class traits> // Removed in C++20
+ constexpr bool operator> (basic_string_view<charT, traits> x,
+ basic_string_view<charT, traits> y) noexcept;
+ template<class charT, class traits> // Removed in C++20
+ constexpr bool operator<=(basic_string_view<charT, traits> x,
+ basic_string_view<charT, traits> y) noexcept;
+ template<class charT, class traits> // Removed in C++20
+ constexpr bool operator>=(basic_string_view<charT, traits> x,
+ basic_string_view<charT, traits> y) noexcept;
+ template<class charT, class traits> // Since C++20
+ constexpr see below operator<=>(basic_string_view<charT, traits> x,
+ basic_string_view<charT, traits> y) noexcept;
+
+ // see below, sufficient additional overloads of comparison functions
+
+ // 7.10, Inserters and extractors
+ template<class charT, class traits>
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ basic_string_view<charT, traits> str);
+
+ // basic_string_view typedef names
+ typedef basic_string_view<char> string_view;
+ typedef basic_string_view<char8_t> u8string_view; // C++20
+ typedef basic_string_view<char16_t> u16string_view;
+ typedef basic_string_view<char32_t> u32string_view;
+ typedef basic_string_view<wchar_t> wstring_view;
+
+ template<class charT, class traits = char_traits<charT>>
+ class basic_string_view {
+ public:
+ // types
+ typedef traits traits_type;
+ typedef charT value_type;
+ typedef charT* pointer;
+ typedef const charT* const_pointer;
+ typedef charT& reference;
+ typedef const charT& const_reference;
+ typedef implementation-defined const_iterator;
+ typedef const_iterator iterator;
+ typedef reverse_iterator<const_iterator> const_reverse_iterator;
+ typedef const_reverse_iterator reverse_iterator;
+ typedef size_t size_type;
+ typedef ptrdiff_t difference_type;
+ static constexpr size_type npos = size_type(-1);
+
+ // 7.3, basic_string_view constructors and assignment operators
+ constexpr basic_string_view() noexcept;
+ constexpr basic_string_view(const basic_string_view&) noexcept = default;
+ basic_string_view& operator=(const basic_string_view&) noexcept = default;
+ template<class Allocator>
+ constexpr basic_string_view(const charT* str);
+ basic_string_view(nullptr_t) = delete; // C++23
+ constexpr basic_string_view(const charT* str, size_type len);
+ template <class It, class End>
+ constexpr basic_string_view(It begin, End end); // C++20
+ template <class Range>
+ constexpr basic_string_view(Range&& r); // C++23
+
+ // 7.4, basic_string_view iterator support
+ constexpr const_iterator begin() const noexcept;
+ constexpr const_iterator end() const noexcept;
+ constexpr const_iterator cbegin() const noexcept;
+ constexpr const_iterator cend() const noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ const_reverse_iterator rend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ // 7.5, basic_string_view capacity
+ constexpr size_type size() const noexcept;
+ constexpr size_type length() const noexcept;
+ constexpr size_type max_size() const noexcept;
+ constexpr bool empty() const noexcept;
+
+ // 7.6, basic_string_view element access
+ constexpr const_reference operator[](size_type pos) const;
+ constexpr const_reference at(size_type pos) const;
+ constexpr const_reference front() const;
+ constexpr const_reference back() const;
+ constexpr const_pointer data() const noexcept;
+
+ // 7.7, basic_string_view modifiers
+ constexpr void remove_prefix(size_type n);
+ constexpr void remove_suffix(size_type n);
+ constexpr void swap(basic_string_view& s) noexcept;
+
+ size_type copy(charT* s, size_type n, size_type pos = 0) const; // constexpr in C++20
+
+ constexpr basic_string_view substr(size_type pos = 0, size_type n = npos) const;
+ constexpr int compare(basic_string_view s) const noexcept;
+ constexpr int compare(size_type pos1, size_type n1, basic_string_view s) const;
+ constexpr int compare(size_type pos1, size_type n1,
+ basic_string_view s, size_type pos2, size_type n2) const;
+ constexpr int compare(const charT* s) const;
+ constexpr int compare(size_type pos1, size_type n1, const charT* s) const;
+ constexpr int compare(size_type pos1, size_type n1,
+ const charT* s, size_type n2) const;
+ constexpr size_type find(basic_string_view s, size_type pos = 0) const noexcept;
+ constexpr size_type find(charT c, size_type pos = 0) const noexcept;
+ constexpr size_type find(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
+ constexpr size_type find(const charT* s, size_type pos = 0) const noexcept; // noexcept as an extension
+ constexpr size_type rfind(basic_string_view s, size_type pos = npos) const noexcept;
+ constexpr size_type rfind(charT c, size_type pos = npos) const noexcept;
+ constexpr size_type rfind(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
+ constexpr size_type rfind(const charT* s, size_type pos = npos) const noexcept; // noexcept as an extension
+ constexpr size_type find_first_of(basic_string_view s, size_type pos = 0) const noexcept;
+ constexpr size_type find_first_of(charT c, size_type pos = 0) const noexcept;
+ constexpr size_type find_first_of(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
+ constexpr size_type find_first_of(const charT* s, size_type pos = 0) const noexcept; // noexcept as an extension
+ constexpr size_type find_last_of(basic_string_view s, size_type pos = npos) const noexcept;
+ constexpr size_type find_last_of(charT c, size_type pos = npos) const noexcept;
+ constexpr size_type find_last_of(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
+ constexpr size_type find_last_of(const charT* s, size_type pos = npos) const noexcept; // noexcept as an extension
+ constexpr size_type find_first_not_of(basic_string_view s, size_type pos = 0) const noexcept;
+ constexpr size_type find_first_not_of(charT c, size_type pos = 0) const noexcept;
+ constexpr size_type find_first_not_of(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
+ constexpr size_type find_first_not_of(const charT* s, size_type pos = 0) const noexcept; // noexcept as an extension
+ constexpr size_type find_last_not_of(basic_string_view s, size_type pos = npos) const noexcept;
+ constexpr size_type find_last_not_of(charT c, size_type pos = npos) const noexcept;
+ constexpr size_type find_last_not_of(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
+ constexpr size_type find_last_not_of(const charT* s, size_type pos = npos) const noexcept; // noexcept as an extension
+
+ constexpr bool starts_with(basic_string_view s) const noexcept; // C++20
+ constexpr bool starts_with(charT c) const noexcept; // C++20
+ constexpr bool starts_with(const charT* s) const; // C++20
+ constexpr bool ends_with(basic_string_view s) const noexcept; // C++20
+ constexpr bool ends_with(charT c) const noexcept; // C++20
+ constexpr bool ends_with(const charT* s) const; // C++20
+
+ constexpr bool contains(basic_string_view s) const noexcept; // C++23
+ constexpr bool contains(charT c) const noexcept; // C++23
+ constexpr bool contains(const charT* s) const; // C++23
+
+ private:
+ const_pointer data_; // exposition only
+ size_type size_; // exposition only
+ };
+
+ // basic_string_view deduction guides
+ template<class It, class End>
+ basic_string_view(It, End) -> basic_string_view<iter_value_t<It>>; // C++20
+ template<class Range>
+ basic_string_view(Range&&) -> basic_string_view<ranges::range_value_t<Range>>; // C++23
+
+ // 7.11, Hash support
+ template <class T> struct hash;
+ template <> struct hash<string_view>;
+ template <> struct hash<u8string_view>; // C++20
+ template <> struct hash<u16string_view>;
+ template <> struct hash<u32string_view>;
+ template <> struct hash<wstring_view>;
+
+ constexpr basic_string_view<char> operator""sv(const char *str, size_t len) noexcept;
+ constexpr basic_string_view<wchar_t> operator""sv(const wchar_t *str, size_t len) noexcept;
+ constexpr basic_string_view<char8_t> operator""sv(const char8_t *str, size_t len) noexcept; // C++20
+ constexpr basic_string_view<char16_t> operator""sv(const char16_t *str, size_t len) noexcept;
+ constexpr basic_string_view<char32_t> operator""sv(const char32_t *str, size_t len) noexcept;
+
+} // namespace std
+
+*/
+
+// clang-format on
+
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__config>
+#include <__functional/hash.h>
+#include <__functional/unary_function.h>
+#include <__fwd/ostream.h>
+#include <__fwd/string_view.h>
+#include <__iterator/bounded_iter.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__iterator/wrap_iter.h>
+#include <__memory/pointer_traits.h>
+#include <__ranges/concepts.h>
+#include <__ranges/data.h>
+#include <__ranges/enable_borrowed_range.h>
+#include <__ranges/enable_view.h>
+#include <__ranges/size.h>
+#include <__string/char_traits.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_standard_layout.h>
+#include <__type_traits/is_trivial.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__type_traits/type_identity.h>
+#include <cstddef>
+#include <iosfwd>
+#include <limits>
+#include <stdexcept>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [string.view.synop]
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// TODO: This is a workaround for some vendors to carry a downstream diff to accept `nullptr` in
+// string_view constructors. This can be refactored when this exact form isn't needed anymore.
+template <class _Traits>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR inline size_t
+__char_traits_length_checked(const typename _Traits::char_type* __s) _NOEXCEPT {
+ // This needs to be a single statement for C++11 constexpr
+ return _LIBCPP_ASSERT_NON_NULL(
+ __s != nullptr, "null pointer passed to non-null argument of char_traits<...>::length"),
+ _Traits::length(__s);
+}
+
+template <class _CharT, class _Traits>
+class basic_string_view {
+public:
+ // types
+ using traits_type = _Traits;
+ using value_type = _CharT;
+ using pointer = _CharT*;
+ using const_pointer = const _CharT*;
+ using reference = _CharT&;
+ using const_reference = const _CharT&;
+#if defined(_LIBCPP_ABI_BOUNDED_ITERATORS)
+ using const_iterator = __bounded_iter<const_pointer>;
+#elif defined(_LIBCPP_ABI_USE_WRAP_ITER_IN_STD_STRING_VIEW)
+ using const_iterator = __wrap_iter<const_pointer>;
+#else
+ using const_iterator = const_pointer;
+#endif
+ using iterator = const_iterator;
+ using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+ using reverse_iterator = const_reverse_iterator;
+ using size_type = size_t;
+ using difference_type = ptrdiff_t;
+ static _LIBCPP_CONSTEXPR const size_type npos = -1; // size_type(-1);
+
+ static_assert(!is_array<value_type>::value, "Character type of basic_string_view must not be an array");
+ static_assert(is_standard_layout<value_type>::value, "Character type of basic_string_view must be standard-layout");
+ static_assert(is_trivial<value_type>::value, "Character type of basic_string_view must be trivial");
+ static_assert(is_same<_CharT, typename traits_type::char_type>::value,
+ "traits_type::char_type must be the same type as CharT");
+
+ // [string.view.cons], construct/copy
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI basic_string_view() _NOEXCEPT : __data_(nullptr), __size_(0) {}
+
+ _LIBCPP_HIDE_FROM_ABI basic_string_view(const basic_string_view&) _NOEXCEPT = default;
+
+ _LIBCPP_HIDE_FROM_ABI basic_string_view& operator=(const basic_string_view&) _NOEXCEPT = default;
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI basic_string_view(const _CharT* __s, size_type __len) _NOEXCEPT
+ : __data_(__s),
+ __size_(__len) {
+#if _LIBCPP_STD_VER >= 14
+ // Allocations must fit in `ptrdiff_t` for pointer arithmetic to work. If `__len` exceeds it, the input
+ // range could not have been valid. Most likely the caller underflowed some arithmetic and inadvertently
+ // passed in a negative length.
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(
+ __len <= static_cast<size_type>(numeric_limits<difference_type>::max()),
+ "string_view::string_view(_CharT *, size_t): length does not fit in difference_type");
+ _LIBCPP_ASSERT_NON_NULL(
+ __len == 0 || __s != nullptr, "string_view::string_view(_CharT *, size_t): received nullptr");
+#endif
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ template <contiguous_iterator _It, sized_sentinel_for<_It> _End>
+ requires(is_same_v<iter_value_t<_It>, _CharT> && !is_convertible_v<_End, size_type>)
+ constexpr _LIBCPP_HIDE_FROM_ABI basic_string_view(_It __begin, _End __end)
+ : __data_(std::to_address(__begin)), __size_(__end - __begin) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(
+ (__end - __begin) >= 0, "std::string_view::string_view(iterator, sentinel) received invalid range");
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 23
+ template <class _Range>
+ requires(!is_same_v<remove_cvref_t<_Range>, basic_string_view> && ranges::contiguous_range<_Range> &&
+ ranges::sized_range<_Range> && is_same_v<ranges::range_value_t<_Range>, _CharT> &&
+ !is_convertible_v<_Range, const _CharT*> &&
+ (!requires(remove_cvref_t<_Range>& __d) { __d.operator std::basic_string_view<_CharT, _Traits>(); }))
+ constexpr explicit _LIBCPP_HIDE_FROM_ABI basic_string_view(_Range&& __r)
+ : __data_(ranges::data(__r)), __size_(ranges::size(__r)) {}
+#endif // _LIBCPP_STD_VER >= 23
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI basic_string_view(const _CharT* __s)
+ : __data_(__s), __size_(std::__char_traits_length_checked<_Traits>(__s)) {}
+
+#if _LIBCPP_STD_VER >= 23
+ basic_string_view(nullptr_t) = delete;
+#endif
+
+ // [string.view.iterators], iterators
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return cbegin(); }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return cend(); }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT {
+#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
+ return std::__make_bounded_iter(data(), data(), data() + size());
+#else
+ return const_iterator(__data_);
+#endif
+ }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT {
+#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS
+ return std::__make_bounded_iter(data() + size(), data(), data() + size());
+#else
+ return const_iterator(__data_ + __size_);
+#endif
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX17 _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const _NOEXCEPT {
+ return const_reverse_iterator(cend());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX17 _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const _NOEXCEPT {
+ return const_reverse_iterator(cbegin());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX17 _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const _NOEXCEPT {
+ return const_reverse_iterator(cend());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX17 _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const _NOEXCEPT {
+ return const_reverse_iterator(cbegin());
+ }
+
+ // [string.view.capacity], capacity
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __size_; }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI size_type length() const _NOEXCEPT { return __size_; }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT {
+ return numeric_limits<size_type>::max() / sizeof(value_type);
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return __size_ == 0; }
+
+ // [string.view.access], element access
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_reference operator[](size_type __pos) const _NOEXCEPT {
+ return _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__pos < size(), "string_view[] index out of bounds"), __data_[__pos];
+ }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_reference at(size_type __pos) const {
+ return __pos >= size() ? (__throw_out_of_range("string_view::at"), __data_[0]) : __data_[__pos];
+ }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_reference front() const _NOEXCEPT {
+ return _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "string_view::front(): string is empty"), __data_[0];
+ }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_reference back() const _NOEXCEPT {
+ return _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "string_view::back(): string is empty"), __data_[__size_ - 1];
+ }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI const_pointer data() const _NOEXCEPT { return __data_; }
+
+ // [string.view.modifiers], modifiers:
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI void remove_prefix(size_type __n) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n <= size(), "remove_prefix() can't remove more than size()");
+ __data_ += __n;
+ __size_ -= __n;
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI void remove_suffix(size_type __n) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n <= size(), "remove_suffix() can't remove more than size()");
+ __size_ -= __n;
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI void swap(basic_string_view& __other) _NOEXCEPT {
+ const value_type* __p = __data_;
+ __data_ = __other.__data_;
+ __other.__data_ = __p;
+
+ size_type __sz = __size_;
+ __size_ = __other.__size_;
+ __other.__size_ = __sz;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type
+ copy(_CharT* __s, size_type __n, size_type __pos = 0) const {
+ if (__pos > size())
+ __throw_out_of_range("string_view::copy");
+ size_type __rlen = std::min(__n, size() - __pos);
+ _Traits::copy(__s, data() + __pos, __rlen);
+ return __rlen;
+ }
+
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI basic_string_view substr(size_type __pos = 0, size_type __n = npos) const {
+ return __pos > size() ? (__throw_out_of_range("string_view::substr"), basic_string_view())
+ : basic_string_view(data() + __pos, std::min(__n, size() - __pos));
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 int compare(basic_string_view __sv) const _NOEXCEPT {
+ size_type __rlen = std::min(size(), __sv.size());
+ int __retval = _Traits::compare(data(), __sv.data(), __rlen);
+ if (__retval == 0) // first __rlen chars matched
+ __retval = size() == __sv.size() ? 0 : (size() < __sv.size() ? -1 : 1);
+ return __retval;
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI int
+ compare(size_type __pos1, size_type __n1, basic_string_view __sv) const {
+ return substr(__pos1, __n1).compare(__sv);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI int
+ compare(size_type __pos1, size_type __n1, basic_string_view __sv, size_type __pos2, size_type __n2) const {
+ return substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI int compare(const _CharT* __s) const _NOEXCEPT {
+ return compare(basic_string_view(__s));
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI int
+ compare(size_type __pos1, size_type __n1, const _CharT* __s) const {
+ return substr(__pos1, __n1).compare(basic_string_view(__s));
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI int
+ compare(size_type __pos1, size_type __n1, const _CharT* __s, size_type __n2) const {
+ return substr(__pos1, __n1).compare(basic_string_view(__s, __n2));
+ }
+
+ // find
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s.size() == 0 || __s.data() != nullptr, "string_view::find(): received nullptr");
+ return std::__str_find<value_type, size_type, traits_type, npos>(data(), size(), __s.data(), __pos, __s.size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type find(_CharT __c, size_type __pos = 0) const _NOEXCEPT {
+ return std::__str_find<value_type, size_type, traits_type, npos>(data(), size(), __c, __pos);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string_view::find(): received nullptr");
+ return std::__str_find<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find(const _CharT* __s, size_type __pos = 0) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string_view::find(): received nullptr");
+ return std::__str_find<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+ }
+
+ // rfind
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ rfind(basic_string_view __s, size_type __pos = npos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s.size() == 0 || __s.data() != nullptr, "string_view::find(): received nullptr");
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(data(), size(), __s.data(), __pos, __s.size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ rfind(_CharT __c, size_type __pos = npos) const _NOEXCEPT {
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(data(), size(), __c, __pos);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ rfind(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string_view::rfind(): received nullptr");
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ rfind(const _CharT* __s, size_type __pos = npos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string_view::rfind(): received nullptr");
+ return std::__str_rfind<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+ }
+
+ // find_first_of
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_first_of(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s.size() == 0 || __s.data() != nullptr, "string_view::find_first_of(): received nullptr");
+ return std::__str_find_first_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s.data(), __pos, __s.size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_first_of(_CharT __c, size_type __pos = 0) const _NOEXCEPT {
+ return find(__c, __pos);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_first_of(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string_view::find_first_of(): received nullptr");
+ return std::__str_find_first_of<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_first_of(const _CharT* __s, size_type __pos = 0) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string_view::find_first_of(): received nullptr");
+ return std::__str_find_first_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+ }
+
+ // find_last_of
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_last_of(basic_string_view __s, size_type __pos = npos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s.size() == 0 || __s.data() != nullptr, "string_view::find_last_of(): received nullptr");
+ return std::__str_find_last_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s.data(), __pos, __s.size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_last_of(_CharT __c, size_type __pos = npos) const _NOEXCEPT {
+ return rfind(__c, __pos);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_last_of(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string_view::find_last_of(): received nullptr");
+ return std::__str_find_last_of<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_last_of(const _CharT* __s, size_type __pos = npos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string_view::find_last_of(): received nullptr");
+ return std::__str_find_last_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+ }
+
+ // find_first_not_of
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_first_not_of(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(
+ __s.size() == 0 || __s.data() != nullptr, "string_view::find_first_not_of(): received nullptr");
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s.data(), __pos, __s.size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_first_not_of(_CharT __c, size_type __pos = 0) const _NOEXCEPT {
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(data(), size(), __c, __pos);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string_view::find_first_not_of(): received nullptr");
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_first_not_of(const _CharT* __s, size_type __pos = 0) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string_view::find_first_not_of(): received nullptr");
+ return std::__str_find_first_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+ }
+
+ // find_last_not_of
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_last_not_of(basic_string_view __s, size_type __pos = npos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(
+ __s.size() == 0 || __s.data() != nullptr, "string_view::find_last_not_of(): received nullptr");
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s.data(), __pos, __s.size());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_last_not_of(_CharT __c, size_type __pos = npos) const _NOEXCEPT {
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(data(), size(), __c, __pos);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__n == 0 || __s != nullptr, "string_view::find_last_not_of(): received nullptr");
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(data(), size(), __s, __pos, __n);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI size_type
+ find_last_not_of(const _CharT* __s, size_type __pos = npos) const _NOEXCEPT {
+ _LIBCPP_ASSERT_NON_NULL(__s != nullptr, "string_view::find_last_not_of(): received nullptr");
+ return std::__str_find_last_not_of<value_type, size_type, traits_type, npos>(
+ data(), size(), __s, __pos, traits_type::length(__s));
+ }
+
+#if _LIBCPP_STD_VER >= 20
+ constexpr _LIBCPP_HIDE_FROM_ABI bool starts_with(basic_string_view __s) const noexcept {
+ return size() >= __s.size() && compare(0, __s.size(), __s) == 0;
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool starts_with(value_type __c) const noexcept {
+ return !empty() && _Traits::eq(front(), __c);
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool starts_with(const value_type* __s) const noexcept {
+ return starts_with(basic_string_view(__s));
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool ends_with(basic_string_view __s) const noexcept {
+ return size() >= __s.size() && compare(size() - __s.size(), npos, __s) == 0;
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool ends_with(value_type __c) const noexcept {
+ return !empty() && _Traits::eq(back(), __c);
+ }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool ends_with(const value_type* __s) const noexcept {
+ return ends_with(basic_string_view(__s));
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ constexpr _LIBCPP_HIDE_FROM_ABI bool contains(basic_string_view __sv) const noexcept { return find(__sv) != npos; }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool contains(value_type __c) const noexcept { return find(__c) != npos; }
+
+ constexpr _LIBCPP_HIDE_FROM_ABI bool contains(const value_type* __s) const { return find(__s) != npos; }
+#endif
+
+private:
+ const value_type* __data_;
+ size_type __size_;
+};
+_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(basic_string_view);
+
+#if _LIBCPP_STD_VER >= 20
+template <class _CharT, class _Traits>
+inline constexpr bool ranges::enable_view<basic_string_view<_CharT, _Traits>> = true;
+
+template <class _CharT, class _Traits>
+inline constexpr bool ranges::enable_borrowed_range<basic_string_view<_CharT, _Traits> > = true;
+#endif // _LIBCPP_STD_VER >= 20
+
+// [string.view.deduct]
+
+#if _LIBCPP_STD_VER >= 20
+template <contiguous_iterator _It, sized_sentinel_for<_It> _End>
+basic_string_view(_It, _End) -> basic_string_view<iter_value_t<_It>>;
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 23
+template <ranges::contiguous_range _Range>
+basic_string_view(_Range) -> basic_string_view<ranges::range_value_t<_Range>>;
+#endif
+
+// [string.view.comparison]
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(basic_string_view<_CharT, _Traits> __lhs,
+ type_identity_t<basic_string_view<_CharT, _Traits>> __rhs) noexcept {
+ if (__lhs.size() != __rhs.size())
+ return false;
+ return __lhs.compare(__rhs) == 0;
+}
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI constexpr auto operator<=>(basic_string_view<_CharT, _Traits> __lhs,
+ type_identity_t<basic_string_view<_CharT, _Traits>> __rhs) noexcept {
+ if constexpr (requires { typename _Traits::comparison_category; }) {
+ // [string.view]/4
+ static_assert(
+ __comparison_category<typename _Traits::comparison_category>, "return type is not a comparison category type");
+ return static_cast<typename _Traits::comparison_category>(__lhs.compare(__rhs) <=> 0);
+ } else {
+ return static_cast<weak_ordering>(__lhs.compare(__rhs) <=> 0);
+ }
+}
+
+#else
+
+// operator ==
+
+template <class _CharT, class _Traits>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator==(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ if (__lhs.size() != __rhs.size())
+ return false;
+ return __lhs.compare(__rhs) == 0;
+}
+
+// The dummy default template parameters are used to work around a MSVC issue with mangling, see VSO-409326 for details.
+// This applies to the other sufficient overloads below for the other comparison operators.
+template <class _CharT, class _Traits, int = 1>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator==(basic_string_view<_CharT, _Traits> __lhs,
+ __type_identity_t<basic_string_view<_CharT, _Traits> > __rhs) _NOEXCEPT {
+ if (__lhs.size() != __rhs.size())
+ return false;
+ return __lhs.compare(__rhs) == 0;
+}
+
+template <class _CharT, class _Traits, int = 2>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator==(__type_identity_t<basic_string_view<_CharT, _Traits> > __lhs,
+ basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ if (__lhs.size() != __rhs.size())
+ return false;
+ return __lhs.compare(__rhs) == 0;
+}
+
+// operator !=
+template <class _CharT, class _Traits>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator!=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ if (__lhs.size() != __rhs.size())
+ return true;
+ return __lhs.compare(__rhs) != 0;
+}
+
+template <class _CharT, class _Traits, int = 1>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator!=(basic_string_view<_CharT, _Traits> __lhs,
+ __type_identity_t<basic_string_view<_CharT, _Traits> > __rhs) _NOEXCEPT {
+ if (__lhs.size() != __rhs.size())
+ return true;
+ return __lhs.compare(__rhs) != 0;
+}
+
+template <class _CharT, class _Traits, int = 2>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator!=(__type_identity_t<basic_string_view<_CharT, _Traits> > __lhs,
+ basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ if (__lhs.size() != __rhs.size())
+ return true;
+ return __lhs.compare(__rhs) != 0;
+}
+
+// operator <
+template <class _CharT, class _Traits>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator<(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) < 0;
+}
+
+template <class _CharT, class _Traits, int = 1>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator<(basic_string_view<_CharT, _Traits> __lhs,
+ __type_identity_t<basic_string_view<_CharT, _Traits> > __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) < 0;
+}
+
+template <class _CharT, class _Traits, int = 2>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator<(__type_identity_t<basic_string_view<_CharT, _Traits> > __lhs,
+ basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) < 0;
+}
+
+// operator >
+template <class _CharT, class _Traits>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator>(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) > 0;
+}
+
+template <class _CharT, class _Traits, int = 1>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator>(basic_string_view<_CharT, _Traits> __lhs,
+ __type_identity_t<basic_string_view<_CharT, _Traits> > __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) > 0;
+}
+
+template <class _CharT, class _Traits, int = 2>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator>(__type_identity_t<basic_string_view<_CharT, _Traits> > __lhs,
+ basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) > 0;
+}
+
+// operator <=
+template <class _CharT, class _Traits>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator<=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) <= 0;
+}
+
+template <class _CharT, class _Traits, int = 1>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator<=(basic_string_view<_CharT, _Traits> __lhs,
+ __type_identity_t<basic_string_view<_CharT, _Traits> > __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) <= 0;
+}
+
+template <class _CharT, class _Traits, int = 2>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator<=(__type_identity_t<basic_string_view<_CharT, _Traits> > __lhs,
+ basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) <= 0;
+}
+
+// operator >=
+template <class _CharT, class _Traits>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator>=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) >= 0;
+}
+
+template <class _CharT, class _Traits, int = 1>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator>=(basic_string_view<_CharT, _Traits> __lhs,
+ __type_identity_t<basic_string_view<_CharT, _Traits> > __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) >= 0;
+}
+
+template <class _CharT, class _Traits, int = 2>
+_LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
+operator>=(__type_identity_t<basic_string_view<_CharT, _Traits> > __lhs,
+ basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT {
+ return __lhs.compare(__rhs) >= 0;
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _CharT, class _Traits>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, basic_string_view<_CharT, _Traits> __str);
+
+// [string.view.hash]
+template <class _CharT>
+struct __string_view_hash : public __unary_function<basic_string_view<_CharT, char_traits<_CharT> >, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const basic_string_view<_CharT, char_traits<_CharT> > __val) const _NOEXCEPT {
+ return std::__do_string_hash(__val.data(), __val.data() + __val.size());
+ }
+};
+
+template <>
+struct hash<basic_string_view<char, char_traits<char> > > : __string_view_hash<char> {};
+
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+template <>
+struct hash<basic_string_view<char8_t, char_traits<char8_t> > > : __string_view_hash<char8_t> {};
+#endif
+
+template <>
+struct hash<basic_string_view<char16_t, char_traits<char16_t> > > : __string_view_hash<char16_t> {};
+
+template <>
+struct hash<basic_string_view<char32_t, char_traits<char32_t> > > : __string_view_hash<char32_t> {};
+
+#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+struct hash<basic_string_view<wchar_t, char_traits<wchar_t> > > : __string_view_hash<wchar_t> {};
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+inline namespace literals {
+inline namespace string_view_literals {
+inline _LIBCPP_HIDE_FROM_ABI constexpr basic_string_view<char> operator""sv(const char* __str, size_t __len) noexcept {
+ return basic_string_view<char>(__str, __len);
+}
+
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+inline _LIBCPP_HIDE_FROM_ABI constexpr basic_string_view<wchar_t>
+operator""sv(const wchar_t* __str, size_t __len) noexcept {
+ return basic_string_view<wchar_t>(__str, __len);
+}
+# endif
+
+# ifndef _LIBCPP_HAS_NO_CHAR8_T
+inline _LIBCPP_HIDE_FROM_ABI constexpr basic_string_view<char8_t>
+operator""sv(const char8_t* __str, size_t __len) noexcept {
+ return basic_string_view<char8_t>(__str, __len);
+}
+# endif
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr basic_string_view<char16_t>
+operator""sv(const char16_t* __str, size_t __len) noexcept {
+ return basic_string_view<char16_t>(__str, __len);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr basic_string_view<char32_t>
+operator""sv(const char32_t* __str, size_t __len) noexcept {
+ return basic_string_view<char32_t>(__str, __len);
+}
+} // namespace string_view_literals
+} // namespace literals
+#endif
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <concepts>
+# include <cstdlib>
+# include <iterator>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_STRING_VIEW
diff --git a/libcxx/include/__cxx03/strstream b/libcxx/include/__cxx03/strstream
new file mode 100644
index 00000000000000..9ff4024a7c7e21
--- /dev/null
+++ b/libcxx/include/__cxx03/strstream
@@ -0,0 +1,351 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_STRSTREAM
+#define _LIBCPP_STRSTREAM
+
+/*
+ strstream synopsis
+
+class strstreambuf // Removed in C++26
+ : public basic_streambuf<char>
+{
+public:
+ explicit strstreambuf(streamsize alsize_arg = 0); // before C++20
+ strstreambuf() : strstreambuf(0) {} // C++20
+ explicit strstreambuf(streamsize alsize_arg); // C++20
+
+ strstreambuf(void* (*palloc_arg)(size_t), void (*pfree_arg)(void*));
+ strstreambuf(char* gnext_arg, streamsize n, char* pbeg_arg = nullptr);
+ strstreambuf(const char* gnext_arg, streamsize n);
+
+ strstreambuf(signed char* gnext_arg, streamsize n, signed char* pbeg_arg = nullptr);
+ strstreambuf(const signed char* gnext_arg, streamsize n);
+ strstreambuf(unsigned char* gnext_arg, streamsize n, unsigned char* pbeg_arg = nullptr);
+ strstreambuf(const unsigned char* gnext_arg, streamsize n);
+
+ strstreambuf(strstreambuf&& rhs);
+ strstreambuf& operator=(strstreambuf&& rhs);
+
+ virtual ~strstreambuf();
+
+ void swap(strstreambuf& rhs);
+
+ void freeze(bool freezefl = true);
+ char* str();
+ int pcount() const;
+
+protected:
+ virtual int_type overflow (int_type c = EOF);
+ virtual int_type pbackfail(int_type c = EOF);
+ virtual int_type underflow();
+ virtual pos_type seekoff(off_type off, ios_base::seekdir way,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ virtual pos_type seekpos(pos_type sp,
+ ios_base::openmode which = ios_base::in | ios_base::out);
+ virtual streambuf* setbuf(char* s, streamsize n);
+
+private:
+ typedef T1 strstate; // exposition only
+ static const strstate allocated; // exposition only
+ static const strstate constant; // exposition only
+ static const strstate dynamic; // exposition only
+ static const strstate frozen; // exposition only
+ strstate strmode; // exposition only
+ streamsize alsize; // exposition only
+ void* (*palloc)(size_t); // exposition only
+ void (*pfree)(void*); // exposition only
+};
+
+class istrstream // Removed in C++26
+ : public basic_istream<char>
+{
+public:
+ explicit istrstream(const char* s);
+ explicit istrstream(char* s);
+ istrstream(const char* s, streamsize n);
+ istrstream(char* s, streamsize n);
+
+ virtual ~istrstream();
+
+ strstreambuf* rdbuf() const;
+ char *str();
+
+private:
+ strstreambuf sb; // exposition only
+};
+
+class ostrstream // Removed in C++26
+ : public basic_ostream<char>
+{
+public:
+ ostrstream();
+ ostrstream(char* s, int n, ios_base::openmode mode = ios_base::out);
+
+ virtual ~ostrstream();
+
+ strstreambuf* rdbuf() const;
+ void freeze(bool freezefl = true);
+ char* str();
+ int pcount() const;
+
+private:
+ strstreambuf sb; // exposition only
+};
+
+class strstream // Removed in C++26
+ : public basic_iostream<char>
+{
+public:
+ // Types
+ typedef char char_type;
+ typedef char_traits<char>::int_type int_type;
+ typedef char_traits<char>::pos_type pos_type;
+ typedef char_traits<char>::off_type off_type;
+
+ // constructors/destructor
+ strstream();
+ strstream(char* s, int n, ios_base::openmode mode = ios_base::in | ios_base::out);
+
+ virtual ~strstream();
+
+ // Members:
+ strstreambuf* rdbuf() const;
+ void freeze(bool freezefl = true);
+ int pcount() const;
+ char* str();
+
+private:
+ strstreambuf sb; // exposition only
+};
+
+} // std
+
+*/
+
+#include <__config>
+#include <istream>
+#include <ostream>
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER < 26 || defined(_LIBCPP_ENABLE_CXX26_REMOVED_STRSTREAM) || defined(_LIBCPP_BUILDING_LIBRARY)
+
+_LIBCPP_PUSH_MACROS
+# include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_DEPRECATED _LIBCPP_EXPORTED_FROM_ABI strstreambuf : public streambuf {
+public:
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI strstreambuf() : strstreambuf(0) {}
+ explicit strstreambuf(streamsize __alsize);
+# else
+ explicit strstreambuf(streamsize __alsize = 0);
+# endif
+ strstreambuf(void* (*__palloc)(size_t), void (*__pfree)(void*));
+ strstreambuf(char* __gnext, streamsize __n, char* __pbeg = nullptr);
+ strstreambuf(const char* __gnext, streamsize __n);
+
+ strstreambuf(signed char* __gnext, streamsize __n, signed char* __pbeg = nullptr);
+ strstreambuf(const signed char* __gnext, streamsize __n);
+ strstreambuf(unsigned char* __gnext, streamsize __n, unsigned char* __pbeg = nullptr);
+ strstreambuf(const unsigned char* __gnext, streamsize __n);
+
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI strstreambuf(strstreambuf&& __rhs);
+ _LIBCPP_HIDE_FROM_ABI strstreambuf& operator=(strstreambuf&& __rhs);
+# endif // _LIBCPP_CXX03_LANG
+
+ ~strstreambuf() override;
+
+ void swap(strstreambuf& __rhs);
+
+ void freeze(bool __freezefl = true);
+ char* str();
+ int pcount() const;
+
+protected:
+ int_type overflow(int_type __c = EOF) override;
+ int_type pbackfail(int_type __c = EOF) override;
+ int_type underflow() override;
+ pos_type
+ seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __which = ios_base::in | ios_base::out) override;
+ pos_type seekpos(pos_type __sp, ios_base::openmode __which = ios_base::in | ios_base::out) override;
+
+private:
+ typedef unsigned __mode_type;
+ static const __mode_type __allocated = 0x01;
+ static const __mode_type __constant = 0x02;
+ static const __mode_type __dynamic = 0x04;
+ static const __mode_type __frozen = 0x08;
+ static const streamsize __default_alsize = 4096;
+
+ __mode_type __strmode_;
+ streamsize __alsize_;
+ void* (*__palloc_)(size_t);
+ void (*__pfree_)(void*);
+
+ void __init(char* __gnext, streamsize __n, char* __pbeg);
+};
+
+# ifndef _LIBCPP_CXX03_LANG
+
+inline _LIBCPP_HIDE_FROM_ABI strstreambuf::strstreambuf(strstreambuf&& __rhs)
+ : streambuf(__rhs),
+ __strmode_(__rhs.__strmode_),
+ __alsize_(__rhs.__alsize_),
+ __palloc_(__rhs.__palloc_),
+ __pfree_(__rhs.__pfree_) {
+ __rhs.setg(nullptr, nullptr, nullptr);
+ __rhs.setp(nullptr, nullptr);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI strstreambuf& strstreambuf::operator=(strstreambuf&& __rhs) {
+ if (eback() && (__strmode_ & __allocated) != 0 && (__strmode_ & __frozen) == 0) {
+ if (__pfree_)
+ __pfree_(eback());
+ else
+ delete[] eback();
+ }
+ streambuf::operator=(__rhs);
+ __strmode_ = __rhs.__strmode_;
+ __alsize_ = __rhs.__alsize_;
+ __palloc_ = __rhs.__palloc_;
+ __pfree_ = __rhs.__pfree_;
+ __rhs.setg(nullptr, nullptr, nullptr);
+ __rhs.setp(nullptr, nullptr);
+ return *this;
+}
+
+# endif // _LIBCPP_CXX03_LANG
+
+class _LIBCPP_DEPRECATED _LIBCPP_EXPORTED_FROM_ABI istrstream : public istream {
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit istrstream(const char* __s) : istream(&__sb_), __sb_(__s, 0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit istrstream(char* __s) : istream(&__sb_), __sb_(__s, 0) {}
+ _LIBCPP_HIDE_FROM_ABI istrstream(const char* __s, streamsize __n) : istream(&__sb_), __sb_(__s, __n) {}
+ _LIBCPP_HIDE_FROM_ABI istrstream(char* __s, streamsize __n) : istream(&__sb_), __sb_(__s, __n) {}
+
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI istrstream(istrstream&& __rhs) // extension
+ : istream(std::move(static_cast<istream&>(__rhs))), __sb_(std::move(__rhs.__sb_)) {
+ istream::set_rdbuf(&__sb_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI istrstream& operator=(istrstream&& __rhs) {
+ __sb_ = std::move(__rhs.__sb_);
+ istream::operator=(std::move(__rhs));
+ return *this;
+ }
+# endif // _LIBCPP_CXX03_LANG
+
+ ~istrstream() override;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(istrstream& __rhs) {
+ istream::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI strstreambuf* rdbuf() const { return const_cast<strstreambuf*>(&__sb_); }
+ _LIBCPP_HIDE_FROM_ABI char* str() { return __sb_.str(); }
+
+private:
+ strstreambuf __sb_;
+};
+
+class _LIBCPP_DEPRECATED _LIBCPP_EXPORTED_FROM_ABI ostrstream : public ostream {
+public:
+ _LIBCPP_HIDE_FROM_ABI ostrstream() : ostream(&__sb_) {}
+ _LIBCPP_HIDE_FROM_ABI ostrstream(char* __s, int __n, ios_base::openmode __mode = ios_base::out)
+ : ostream(&__sb_), __sb_(__s, __n, __s + (__mode & ios::app ? std::strlen(__s) : 0)) {}
+
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI ostrstream(ostrstream&& __rhs) // extension
+ : ostream(std::move(static_cast<ostream&>(__rhs))), __sb_(std::move(__rhs.__sb_)) {
+ ostream::set_rdbuf(&__sb_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ostrstream& operator=(ostrstream&& __rhs) {
+ __sb_ = std::move(__rhs.__sb_);
+ ostream::operator=(std::move(__rhs));
+ return *this;
+ }
+# endif // _LIBCPP_CXX03_LANG
+
+ ~ostrstream() override;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(ostrstream& __rhs) {
+ ostream::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI strstreambuf* rdbuf() const { return const_cast<strstreambuf*>(&__sb_); }
+ _LIBCPP_HIDE_FROM_ABI void freeze(bool __freezefl = true) { __sb_.freeze(__freezefl); }
+ _LIBCPP_HIDE_FROM_ABI char* str() { return __sb_.str(); }
+ _LIBCPP_HIDE_FROM_ABI int pcount() const { return __sb_.pcount(); }
+
+private:
+ strstreambuf __sb_; // exposition only
+};
+
+class _LIBCPP_DEPRECATED _LIBCPP_EXPORTED_FROM_ABI strstream : public iostream {
+public:
+ // Types
+ typedef char char_type;
+ typedef char_traits<char>::int_type int_type;
+ typedef char_traits<char>::pos_type pos_type;
+ typedef char_traits<char>::off_type off_type;
+
+ // constructors/destructor
+ _LIBCPP_HIDE_FROM_ABI strstream() : iostream(&__sb_) {}
+ _LIBCPP_HIDE_FROM_ABI strstream(char* __s, int __n, ios_base::openmode __mode = ios_base::in | ios_base::out)
+ : iostream(&__sb_), __sb_(__s, __n, __s + (__mode & ios::app ? std::strlen(__s) : 0)) {}
+
+# ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI strstream(strstream&& __rhs) // extension
+ : iostream(std::move(static_cast<iostream&>(__rhs))), __sb_(std::move(__rhs.__sb_)) {
+ iostream::set_rdbuf(&__sb_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI strstream& operator=(strstream&& __rhs) {
+ __sb_ = std::move(__rhs.__sb_);
+ iostream::operator=(std::move(__rhs));
+ return *this;
+ }
+# endif // _LIBCPP_CXX03_LANG
+
+ ~strstream() override;
+
+ _LIBCPP_HIDE_FROM_ABI void swap(strstream& __rhs) {
+ iostream::swap(__rhs);
+ __sb_.swap(__rhs.__sb_);
+ }
+
+ // Members:
+ _LIBCPP_HIDE_FROM_ABI strstreambuf* rdbuf() const { return const_cast<strstreambuf*>(&__sb_); }
+ _LIBCPP_HIDE_FROM_ABI void freeze(bool __freezefl = true) { __sb_.freeze(__freezefl); }
+ _LIBCPP_HIDE_FROM_ABI int pcount() const { return __sb_.pcount(); }
+ _LIBCPP_HIDE_FROM_ABI char* str() { return __sb_.str(); }
+
+private:
+ strstreambuf __sb_; // exposition only
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_STD_VER < 26 || defined(_LIBCPP_ENABLE_CXX26_REMOVED_STRSTREAM) || defined(_LIBCPP_BUILDING_LIBRARY)
+
+#endif // _LIBCPP_STRSTREAM
diff --git a/libcxx/include/__cxx03/syncstream b/libcxx/include/__cxx03/syncstream
new file mode 100644
index 00000000000000..e6f35b6f428eda
--- /dev/null
+++ b/libcxx/include/__cxx03/syncstream
@@ -0,0 +1,512 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SYNCSTREAM
+#define _LIBCPP_SYNCSTREAM
+
+/*
+ syncstream synopsis
+
+#include <ostream> // see [ostream.syn]
+
+namespace std {
+ template<class charT, class traits, class Allocator>
+ class basic_syncbuf;
+
+ // [syncstream.syncbuf.special], specialized algorithms
+ template<class charT, class traits, class Allocator>
+ void swap(basic_syncbuf<charT, traits, Allocator>&,
+ basic_syncbuf<charT, traits, Allocator>&);
+
+ using syncbuf = basic_syncbuf<char>;
+ using wsyncbuf = basic_syncbuf<wchar_t>;
+
+ template<class charT, class traits, class Allocator>
+ class basic_osyncstream;
+
+ using osyncstream = basic_osyncstream<char>;
+ using wosyncstream = basic_osyncstream<wchar_t>;
+
+ template<class charT, class traits, class Allocator>
+ class basic_syncbuf : public basic_streambuf<charT, traits> {
+ public:
+ using char_type = charT;
+ using int_type = typename traits::int_type;
+ using pos_type = typename traits::pos_type;
+ using off_type = typename traits::off_type;
+ using traits_type = traits;
+ using allocator_type = Allocator;
+
+ using streambuf_type = basic_streambuf<charT, traits>;
+
+ // [syncstream.syncbuf.cons], construction and destruction
+ explicit basic_syncbuf(streambuf_type* obuf = nullptr)
+ : basic_syncbuf(obuf, Allocator()) {}
+ basic_syncbuf(streambuf_type*, const Allocator&);
+ basic_syncbuf(basic_syncbuf&&);
+ ~basic_syncbuf();
+
+ // [syncstream.syncbuf.assign], assignment and swap
+ basic_syncbuf& operator=(basic_syncbuf&&);
+ void swap(basic_syncbuf&);
+
+ // [syncstream.syncbuf.members], member functions
+ bool emit();
+ streambuf_type* get_wrapped() const noexcept;
+ allocator_type get_allocator() const noexcept;
+ void set_emit_on_sync(bool) noexcept;
+
+ protected:
+ // [syncstream.syncbuf.virtuals], overridden virtual functions
+ int sync() override;
+
+ private:
+ streambuf_type* wrapped; // exposition only
+ bool emit_on_sync{}; // exposition only
+ };
+
+ // [syncstream.syncbuf.special], specialized algorithms
+ template<class charT, class traits, class Allocator>
+ void swap(basic_syncbuf<charT, traits, Allocator>&,
+ basic_syncbuf<charT, traits, Allocator>&);
+
+ template<class charT, class traits, class Allocator>
+ class basic_osyncstream : public basic_ostream<charT, traits> {
+ public:
+ using char_type = charT;
+ using int_type = typename traits::int_type;
+ using pos_type = typename traits::pos_type;
+ using off_type = typename traits::off_type;
+ using traits_type = traits;
+
+ using allocator_type = Allocator;
+ using streambuf_type = basic_streambuf<charT, traits>;
+ using syncbuf_type = basic_syncbuf<charT, traits, Allocator>;
+
+ // [syncstream.osyncstream.cons], construction and destruction
+ basic_osyncstream(streambuf_type*, const Allocator&);
+ explicit basic_osyncstream(streambuf_type* obuf)
+ : basic_osyncstream(obuf, Allocator()) {}
+ basic_osyncstream(basic_ostream<charT, traits>& os, const Allocator& allocator)
+ : basic_osyncstream(os.rdbuf(), allocator) {}
+ explicit basic_osyncstream(basic_ostream<charT, traits>& os)
+ : basic_osyncstream(os, Allocator()) {}
+ basic_osyncstream(basic_osyncstream&&) noexcept;
+ ~basic_osyncstream();
+
+ // [syncstream.osyncstream.assign], assignment
+ basic_osyncstream& operator=(basic_osyncstream&&);
+
+ // [syncstream.osyncstream.members], member functions
+ void emit();
+ streambuf_type* get_wrapped() const noexcept;
+ syncbuf_type* rdbuf() const noexcept { return const_cast<syncbuf_type*>(addressof(sb)); }
+
+ private:
+ syncbuf_type sb; // exposition only
+ };
+}
+
+*/
+
+#include <__config>
+#include <__utility/move.h>
+#include <ios>
+#include <iosfwd> // required for declaration of default arguments
+#include <streambuf>
+#include <string>
+
+#ifndef _LIBCPP_HAS_NO_THREADS
+# include <map>
+# include <mutex>
+# include <shared_mutex>
+#endif
+
+// standard-mandated includes
+
+// [syncstream.syn]
+#include <ostream>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_SYNCSTREAM)
+
+// [syncstream.syncbuf.overview]/1
+// Class template basic_syncbuf stores character data written to it,
+// known as the associated output, into internal buffers allocated
+// using the object's allocator. The associated output is transferred
+// to the wrapped stream buffer object *wrapped when emit() is called
+// or when the basic_syncbuf object is destroyed. Such transfers are
+// atomic with respect to transfers by other basic_syncbuf objects
+// with the same wrapped stream buffer object.
+//
+// This helper singleton is used to implement the required
+// synchronisation guarantees.
+# ifndef _LIBCPP_HAS_NO_THREADS
+class __wrapped_streambuf_mutex {
+ _LIBCPP_HIDE_FROM_ABI __wrapped_streambuf_mutex() = default;
+
+public:
+ __wrapped_streambuf_mutex(const __wrapped_streambuf_mutex&) = delete;
+ __wrapped_streambuf_mutex& operator=(const __wrapped_streambuf_mutex&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI void __inc_reference([[maybe_unused]] void* __ptr) {
+ _LIBCPP_ASSERT_INTERNAL(__ptr != nullptr, "non-wrapped streambufs are never written to");
+ unique_lock __lock{__mutex_};
+ ++__lut_[reinterpret_cast<uintptr_t>(__ptr)].__count;
+ }
+
+ // pre: __ptr is in __lut_
+ _LIBCPP_HIDE_FROM_ABI void __dec_reference([[maybe_unused]] void* __ptr) noexcept {
+ unique_lock __lock{__mutex_};
+
+ auto __it = __get_it(__ptr);
+ if (__it->second.__count == 1)
+ __lut_.erase(__it);
+ else
+ --__it->second.__count;
+ }
+
+ // TODO
+ // This function causes emit() aquire two mutexes:
+ // - __mutex_ shared
+ // _ __get_it(__ptr)->second.__mutex exclusive
+ //
+ // Instead store a pointer to __get_it(__ptr)->second.__mutex when
+ // calling __inc_reference.
+ //
+ // pre: __ptr is in __lut_
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI lock_guard<mutex> __get_lock([[maybe_unused]] void* __ptr) noexcept {
+ shared_lock __lock{__mutex_};
+ return lock_guard{__get_it(__ptr)->second.__mutex};
+ }
+
+ // This function is used for testing.
+ //
+ // It is allowed to call this function with a non-registered pointer.
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI size_t __get_count([[maybe_unused]] void* __ptr) noexcept {
+ _LIBCPP_ASSERT_INTERNAL(__ptr != nullptr, "non-wrapped streambufs are never written to");
+ shared_lock __lock{__mutex_};
+
+ auto __it = __lut_.find(reinterpret_cast<uintptr_t>(__ptr));
+ return __it != __lut_.end() ? __it->second.__count : 0;
+ }
+
+ [[nodiscard]] static _LIBCPP_HIDE_FROM_ABI __wrapped_streambuf_mutex& __instance() noexcept {
+ static __wrapped_streambuf_mutex __result;
+ return __result;
+ }
+
+private:
+ struct __value {
+ mutex __mutex;
+ size_t __count{0};
+ };
+
+ shared_mutex __mutex_;
+ map<uintptr_t, __value> __lut_;
+
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI map<uintptr_t, __value>::iterator __get_it(void* __ptr) noexcept {
+ _LIBCPP_ASSERT_INTERNAL(__ptr != nullptr, "non-wrapped streambufs are never written to");
+
+ auto __it = __lut_.find(reinterpret_cast<uintptr_t>(__ptr));
+ _LIBCPP_ASSERT_INTERNAL(__it != __lut_.end(), "using a wrapped streambuf that has not been registered");
+ _LIBCPP_ASSERT_INTERNAL(__it->second.__count >= 1, "found an inactive streambuf wrapper");
+ return __it;
+ }
+};
+# endif // _LIBCPP_HAS_NO_THREADS
+
+// basic_syncbuf
+
+// The class uses a basic_string<_CharT, _Traits, _Allocator> as
+// internal buffer. Per [syncstream.syncbuf.cons]/4
+// Remarks: A copy of allocator is used to allocate memory for
+// internal buffers holding the associated output.
+//
+// Therefore the allocator used in the constructor is passed to the
+// basic_string. The class does not keep a copy of this allocator.
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_TEMPLATE_VIS basic_syncbuf : public basic_streambuf<_CharT, _Traits> {
+public:
+ using char_type = _CharT;
+ using traits_type = _Traits;
+ using int_type = typename traits_type::int_type;
+ using pos_type = typename traits_type::pos_type;
+ using off_type = typename traits_type::off_type;
+ using allocator_type = _Allocator;
+
+ using streambuf_type = basic_streambuf<_CharT, _Traits>;
+
+ // [syncstream.syncbuf.cons], construction and destruction
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_syncbuf(streambuf_type* __obuf = nullptr)
+ : basic_syncbuf(__obuf, _Allocator()) {}
+
+ _LIBCPP_HIDE_FROM_ABI basic_syncbuf(streambuf_type* __obuf, _Allocator const& __alloc)
+ : __wrapped_(__obuf), __str_(__alloc) {
+ __inc_reference();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI basic_syncbuf(basic_syncbuf&& __other)
+ : __wrapped_(__other.get_wrapped()), __str_(std::move(__other.__str_)), __emit_on_sync_(__other.__emit_on_sync_) {
+ __move_common(__other);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI ~basic_syncbuf() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ emit();
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __dec_reference();
+ }
+
+ // [syncstream.syncbuf.assign], assignment and swap
+
+ _LIBCPP_HIDE_FROM_ABI basic_syncbuf& operator=(basic_syncbuf&& __other) {
+ // The function is specified to call emit. This call should
+ // propagate the exception thrown.
+ emit();
+ __dec_reference();
+
+ __wrapped_ = __other.get_wrapped();
+ __str_ = std::move(__other.__str_);
+ __emit_on_sync_ = __other.__emit_on_sync_;
+
+ __move_common(__other);
+
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(basic_syncbuf& __other) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ allocator_traits<_Allocator>::propagate_on_container_swap::value || get_allocator() == __other.get_allocator(),
+ "violates the mandated swap precondition");
+
+ basic_syncbuf __tmp(std::move(__other));
+ __other = std::move(*this);
+ *this = std::move(__tmp);
+ }
+
+ // [syncstream.syncbuf.members], member functions
+
+ _LIBCPP_HIDE_FROM_ABI bool emit() { return emit(false); }
+
+ _LIBCPP_HIDE_FROM_ABI streambuf_type* get_wrapped() const noexcept { return __wrapped_; }
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const noexcept { return __str_.get_allocator(); }
+
+ _LIBCPP_HIDE_FROM_ABI void set_emit_on_sync(bool __b) noexcept { __emit_on_sync_ = __b; }
+
+protected:
+ // [syncstream.syncbuf.virtuals], overridden virtual functions
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ int sync() override {
+ if (__emit_on_sync_ && !emit(true))
+ return -1;
+ return 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI_VIRTUAL
+ int_type overflow(int_type __c = traits_type::eof()) override {
+ if (traits_type::eq_int_type(__c, traits_type::eof()))
+ return traits_type::not_eof(__c);
+
+ if (this->pptr() == this->epptr()) {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+ size_t __size = __str_.size();
+ __str_.resize(__str_.capacity() + 1);
+ _LIBCPP_ASSERT_INTERNAL(__str_.size() > __size, "the buffer hasn't grown");
+
+ char_type* __p = static_cast<char_type*>(__str_.data());
+ this->setp(__p, __p + __str_.size());
+ this->pbump(__size);
+
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ return traits_type::eof();
+ }
+# endif
+ }
+
+ return this->sputc(traits_type::to_char_type(__c));
+ }
+
+private:
+ streambuf_type* __wrapped_;
+
+ // TODO Use a more generic buffer.
+ // That buffer should be light with almost no additional headers. Then
+ // it can be use here, the __retarget_buffer, and place that use
+ // the now deprecated get_temporary_buffer
+
+ basic_string<_CharT, _Traits, _Allocator> __str_;
+ bool __emit_on_sync_{false};
+
+ _LIBCPP_HIDE_FROM_ABI bool emit(bool __flush) {
+ if (!__wrapped_)
+ return false;
+
+# ifndef _LIBCPP_HAS_NO_THREADS
+ lock_guard<mutex> __lock = __wrapped_streambuf_mutex::__instance().__get_lock(__wrapped_);
+# endif
+
+ bool __result = true;
+ if (this->pptr() != this->pbase()) {
+ _LIBCPP_ASSERT_INTERNAL(this->pbase() && this->pptr() && this->epptr(), "all put area pointers shold be valid");
+
+ // The __str_ does not know how much of its buffer is used. This
+ // information is extracted from the information of the base class.
+ __result &= (__wrapped_->sputn(this->pbase(), this->pptr() - this->pbase()) != -1);
+ // Clears the buffer, but keeps the contents (and) size of the
+ // internal buffer.
+ this->setp(this->pbase(), this->epptr());
+ }
+
+ if (__flush)
+ __result &= (__wrapped_->pubsync() != -1);
+
+ return __result;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __move_common(basic_syncbuf& __other) {
+ // Adjust the put area pointers to our buffer.
+ char_type* __p = static_cast<char_type*>(__str_.data());
+ this->setp(__p, __p + __str_.size());
+ this->pbump(__other.pptr() - __other.pbase());
+
+ // Clear __other_ so the destructor will act as a NOP.
+ __other.setp(nullptr, nullptr);
+ __other.__wrapped_ = nullptr;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __inc_reference() {
+# ifndef _LIBCPP_HAS_NO_THREADS
+ if (__wrapped_)
+ __wrapped_streambuf_mutex::__instance().__inc_reference(__wrapped_);
+# endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __dec_reference() noexcept {
+# ifndef _LIBCPP_HAS_NO_THREADS
+ if (__wrapped_)
+ __wrapped_streambuf_mutex::__instance().__dec_reference(__wrapped_);
+# endif
+ }
+};
+
+using std::syncbuf;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using std::wsyncbuf;
+# endif
+
+// [syncstream.syncbuf.special], specialized algorithms
+template <class _CharT, class _Traits, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI void
+swap(basic_syncbuf<_CharT, _Traits, _Allocator>& __lhs, basic_syncbuf<_CharT, _Traits, _Allocator>& __rhs) {
+ __lhs.swap(__rhs);
+}
+
+// basic_osyncstream
+
+template <class _CharT, class _Traits, class _Allocator>
+class _LIBCPP_TEMPLATE_VIS basic_osyncstream : public basic_ostream<_CharT, _Traits> {
+public:
+ using char_type = _CharT;
+ using traits_type = _Traits;
+ using int_type = typename traits_type::int_type;
+ using pos_type = typename traits_type::pos_type;
+ using off_type = typename traits_type::off_type;
+
+ using allocator_type = _Allocator;
+ using streambuf_type = basic_streambuf<char_type, traits_type>;
+ using syncbuf_type = basic_syncbuf<char_type, traits_type, allocator_type>;
+
+ // [syncstream.osyncstream.cons], construction and destruction
+
+ _LIBCPP_HIDE_FROM_ABI basic_osyncstream(streambuf_type* __obuf, allocator_type const& __alloc)
+ : basic_ostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(__obuf, __alloc) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_osyncstream(streambuf_type* __obuf)
+ : basic_osyncstream(__obuf, allocator_type()) {}
+
+ _LIBCPP_HIDE_FROM_ABI basic_osyncstream(basic_ostream<char_type, traits_type>& __os, allocator_type const& __alloc)
+ : basic_osyncstream(__os.rdbuf(), __alloc) {}
+
+ _LIBCPP_HIDE_FROM_ABI explicit basic_osyncstream(basic_ostream<char_type, traits_type>& __os)
+ : basic_osyncstream(__os, allocator_type()) {}
+
+ _LIBCPP_HIDE_FROM_ABI basic_osyncstream(basic_osyncstream&& __other) noexcept
+ : basic_ostream<_CharT, _Traits>(std::addressof(__sb_)), __sb_(std::move(__other.__sb_)) {
+ this->set_rdbuf(std::addressof(__sb_));
+ }
+
+ // [syncstream.osyncstream.assign], assignment
+
+ _LIBCPP_HIDE_FROM_ABI basic_osyncstream& operator=(basic_osyncstream&& __other) = default;
+
+ // [syncstream.osyncstream.members], member functions
+
+ _LIBCPP_HIDE_FROM_ABI void emit() {
+ // The basic_ostream::put places the sentry in a try
+ // catch, this does not match the wording of the standard
+ // [ostream.unformatted]
+ // TODO validate other unformatted output functions.
+ typename basic_ostream<char_type, traits_type>::sentry __s(*this);
+ if (__s) {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif
+
+ if (__sb_.emit() == false)
+ this->setstate(ios::badbit);
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ this->__set_badbit_and_consider_rethrow();
+ }
+# endif
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI streambuf_type* get_wrapped() const noexcept { return __sb_.get_wrapped(); }
+
+ _LIBCPP_HIDE_FROM_ABI syncbuf_type* rdbuf() const noexcept {
+ return const_cast<syncbuf_type*>(std::addressof(__sb_));
+ }
+
+private:
+ syncbuf_type __sb_;
+};
+
+using std::osyncstream;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+using std::wosyncstream;
+# endif
+
+#endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_SYNCSTREAM)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_SYNCSTREAM
diff --git a/libcxx/include/__cxx03/system_error b/libcxx/include/__cxx03/system_error
new file mode 100644
index 00000000000000..eeab347788a9a5
--- /dev/null
+++ b/libcxx/include/__cxx03/system_error
@@ -0,0 +1,171 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SYSTEM_ERROR
+#define _LIBCPP_SYSTEM_ERROR
+
+/*
+ system_error synopsis
+
+namespace std
+{
+
+class error_category
+{
+public:
+ virtual ~error_category() noexcept;
+
+ constexpr error_category();
+ error_category(const error_category&) = delete;
+ error_category& operator=(const error_category&) = delete;
+
+ virtual const char* name() const noexcept = 0;
+ virtual error_condition default_error_condition(int ev) const noexcept;
+ virtual bool equivalent(int code, const error_condition& condition) const noexcept;
+ virtual bool equivalent(const error_code& code, int condition) const noexcept;
+ virtual string message(int ev) const = 0;
+
+ bool operator==(const error_category& rhs) const noexcept;
+ bool operator!=(const error_category& rhs) const noexcept; // removed in C++20
+ bool operator<(const error_category& rhs) const noexcept; // removed in C++20
+ strong_ordering operator<=>(const error_category& rhs) const noexcept; // C++20
+};
+
+const error_category& generic_category() noexcept;
+const error_category& system_category() noexcept;
+
+template <class T> struct is_error_code_enum
+ : public false_type {};
+
+template <class T> struct is_error_condition_enum
+ : public false_type {};
+
+template <class _Tp>
+inline constexpr bool is_error_condition_enum_v = is_error_condition_enum<_Tp>::value; // C++17
+
+template <class _Tp>
+inline constexpr bool is_error_code_enum_v = is_error_code_enum<_Tp>::value; // C++17
+
+class error_code
+{
+public:
+ // constructors:
+ error_code() noexcept;
+ error_code(int val, const error_category& cat) noexcept;
+ template <class ErrorCodeEnum>
+ error_code(ErrorCodeEnum e) noexcept;
+
+ // modifiers:
+ void assign(int val, const error_category& cat) noexcept;
+ template <class ErrorCodeEnum>
+ error_code& operator=(ErrorCodeEnum e) noexcept;
+ void clear() noexcept;
+
+ // observers:
+ int value() const noexcept;
+ const error_category& category() const noexcept;
+ error_condition default_error_condition() const noexcept;
+ string message() const;
+ explicit operator bool() const noexcept;
+};
+
+// non-member functions:
+template <class charT, class traits>
+ basic_ostream<charT,traits>&
+ operator<<(basic_ostream<charT,traits>& os, const error_code& ec);
+
+class error_condition
+{
+public:
+ // constructors:
+ error_condition() noexcept;
+ error_condition(int val, const error_category& cat) noexcept;
+ template <class ErrorConditionEnum>
+ error_condition(ErrorConditionEnum e) noexcept;
+
+ // modifiers:
+ void assign(int val, const error_category& cat) noexcept;
+ template <class ErrorConditionEnum>
+ error_condition& operator=(ErrorConditionEnum e) noexcept;
+ void clear() noexcept;
+
+ // observers:
+ int value() const noexcept;
+ const error_category& category() const noexcept;
+ string message() const noexcept;
+ explicit operator bool() const noexcept;
+};
+
+class system_error
+ : public runtime_error
+{
+public:
+ system_error(error_code ec, const string& what_arg);
+ system_error(error_code ec, const char* what_arg);
+ system_error(error_code ec);
+ system_error(int ev, const error_category& ecat, const string& what_arg);
+ system_error(int ev, const error_category& ecat, const char* what_arg);
+ system_error(int ev, const error_category& ecat);
+
+ const error_code& code() const noexcept;
+ const char* what() const noexcept;
+};
+
+template <> struct is_error_condition_enum<errc>
+ : true_type { }
+
+error_code make_error_code(errc e) noexcept;
+error_condition make_error_condition(errc e) noexcept;
+
+// Comparison operators:
+bool operator==(const error_code& lhs, const error_code& rhs) noexcept;
+bool operator==(const error_code& lhs, const error_condition& rhs) noexcept;
+bool operator==(const error_condition& lhs, const error_code& rhs) noexcept; // removed in C++20
+bool operator==(const error_condition& lhs, const error_condition& rhs) noexcept;
+bool operator!=(const error_code& lhs, const error_code& rhs) noexcept; // removed in C++20
+bool operator!=(const error_code& lhs, const error_condition& rhs) noexcept; // removed in C++20
+bool operator!=(const error_condition& lhs, const error_code& rhs) noexcept; // removed in C++20
+bool operator!=(const error_condition& lhs, const error_condition& rhs) noexcept; // removed in C++20
+bool operator<(const error_condition& lhs, const error_condition& rhs) noexcept; // removed in C++20
+bool operator<(const error_code& lhs, const error_code& rhs) noexcept; // removed in C++20
+strong_ordering operator<=>(const error_code& lhs, const error_code& rhs) noexcept; // C++20
+strong_ordering operator<=>(const error_condition& lhs, const error_condition& rhs) noexcept; // C++20
+
+template <> struct hash<std::error_code>;
+template <> struct hash<std::error_condition>;
+
+} // std
+
+*/
+
+#include <__config>
+#include <__system_error/errc.h>
+#include <__system_error/error_category.h>
+#include <__system_error/error_code.h>
+#include <__system_error/error_condition.h>
+#include <__system_error/system_error.h>
+#include <version>
+
+// standard-mandated includes
+
+// [system.error.syn]
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdint>
+# include <cstring>
+# include <limits>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_SYSTEM_ERROR
diff --git a/libcxx/include/__cxx03/tgmath.h b/libcxx/include/__cxx03/tgmath.h
new file mode 100644
index 00000000000000..e6f0a4ab2611fa
--- /dev/null
+++ b/libcxx/include/__cxx03/tgmath.h
@@ -0,0 +1,34 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_TGMATH_H
+#define _LIBCPP_TGMATH_H
+
+/*
+ tgmath.h synopsis
+
+#include <ctgmath>
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#ifdef __cplusplus
+# include <ctgmath>
+#else
+# if __has_include_next(<tgmath.h>)
+# include_next <tgmath.h>
+# endif
+#endif
+
+#endif // _LIBCPP_TGMATH_H
diff --git a/libcxx/include/__cxx03/thread b/libcxx/include/__cxx03/thread
new file mode 100644
index 00000000000000..25cb7ce6d7231e
--- /dev/null
+++ b/libcxx/include/__cxx03/thread
@@ -0,0 +1,130 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_THREAD
+#define _LIBCPP_THREAD
+
+/*
+
+ thread synopsis
+
+namespace std
+{
+
+class thread
+{
+public:
+ class id;
+ typedef pthread_t native_handle_type;
+
+ thread() noexcept;
+ template <class F, class ...Args> explicit thread(F&& f, Args&&... args);
+ ~thread();
+
+ thread(const thread&) = delete;
+ thread(thread&& t) noexcept;
+
+ thread& operator=(const thread&) = delete;
+ thread& operator=(thread&& t) noexcept;
+
+ void swap(thread& t) noexcept;
+
+ bool joinable() const noexcept;
+ void join();
+ void detach();
+ id get_id() const noexcept;
+ native_handle_type native_handle();
+
+ static unsigned hardware_concurrency() noexcept;
+};
+
+void swap(thread& x, thread& y) noexcept;
+
+class thread::id
+{
+public:
+ id() noexcept;
+};
+
+bool operator==(thread::id x, thread::id y) noexcept;
+bool operator!=(thread::id x, thread::id y) noexcept; // removed in C++20
+bool operator< (thread::id x, thread::id y) noexcept; // removed in C++20
+bool operator<=(thread::id x, thread::id y) noexcept; // removed in C++20
+bool operator> (thread::id x, thread::id y) noexcept; // removed in C++20
+bool operator>=(thread::id x, thread::id y) noexcept; // removed in C++20
+strong_ordering operator<=>(thread::id x, thread::id y) noexcept; // C++20
+
+template<class charT, class traits>
+basic_ostream<charT, traits>&
+operator<<(basic_ostream<charT, traits>& out, thread::id id);
+
+template<class charT>
+struct formatter<thread::id, charT>;
+
+namespace this_thread
+{
+
+thread::id get_id() noexcept;
+
+void yield() noexcept;
+
+template <class Clock, class Duration>
+void sleep_until(const chrono::time_point<Clock, Duration>& abs_time);
+
+template <class Rep, class Period>
+void sleep_for(const chrono::duration<Rep, Period>& rel_time);
+
+} // this_thread
+
+} // std
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+
+# include <__thread/formatter.h>
+# include <__thread/jthread.h>
+# include <__thread/support.h>
+# include <__thread/this_thread.h>
+# include <__thread/thread.h>
+# include <version>
+
+// standard-mandated includes
+
+// [thread.syn]
+# include <compare>
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+#endif // !defined(_LIBCPP_HAS_NO_THREADS)
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES)
+# include <cstddef>
+# include <ctime>
+# include <iosfwd>
+# include <ratio>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
+# include <chrono>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstring>
+# include <functional>
+# include <new>
+# include <system_error>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_THREAD
diff --git a/libcxx/include/__cxx03/tuple b/libcxx/include/__cxx03/tuple
new file mode 100644
index 00000000000000..081b90c7bbec54
--- /dev/null
+++ b/libcxx/include/__cxx03/tuple
@@ -0,0 +1,1419 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_TUPLE
+#define _LIBCPP_TUPLE
+
+// clang-format off
+
+/*
+ tuple synopsis
+
+namespace std
+{
+
+template <class... T>
+class tuple {
+public:
+ explicit(see-below) constexpr tuple();
+ explicit(see-below) tuple(const T&...); // constexpr in C++14
+ template <class... U>
+ explicit(see-below) tuple(U&&...); // constexpr in C++14
+ tuple(const tuple&) = default;
+ tuple(tuple&&) = default;
+
+ template<class... UTypes>
+ constexpr explicit(see-below) tuple(tuple<UTypes...>&); // C++23
+ template <class... U>
+ explicit(see-below) tuple(const tuple<U...>&); // constexpr in C++14
+ template <class... U>
+ explicit(see-below) tuple(tuple<U...>&&); // constexpr in C++14
+ template<class... UTypes>
+ constexpr explicit(see-below) tuple(const tuple<UTypes...>&&); // C++23
+
+ template<class U1, class U2>
+ constexpr explicit(see-below) tuple(pair<U1, U2>&); // iff sizeof...(Types) == 2 // C++23
+ template <class U1, class U2>
+ explicit(see-below) tuple(const pair<U1, U2>&); // iff sizeof...(T) == 2 // constexpr in C++14
+ template <class U1, class U2>
+ explicit(see-below) tuple(pair<U1, U2>&&); // iff sizeof...(T) == 2 // constexpr in C++14
+ template<class U1, class U2>
+ constexpr explicit(see-below) tuple(const pair<U1, U2>&&); // iff sizeof...(Types) == 2 // C++23
+
+ // allocator-extended constructors
+ template <class Alloc>
+ tuple(allocator_arg_t, const Alloc& a);
+ template <class Alloc>
+ explicit(see-below) tuple(allocator_arg_t, const Alloc& a, const T&...); // constexpr in C++20
+ template <class Alloc, class... U>
+ explicit(see-below) tuple(allocator_arg_t, const Alloc& a, U&&...); // constexpr in C++20
+ template <class Alloc>
+ tuple(allocator_arg_t, const Alloc& a, const tuple&); // constexpr in C++20
+ template <class Alloc>
+ tuple(allocator_arg_t, const Alloc& a, tuple&&); // constexpr in C++20
+ template<class Alloc, class... UTypes>
+ constexpr explicit(see-below)
+ tuple(allocator_arg_t, const Alloc& a, tuple<UTypes...>&); // C++23
+ template <class Alloc, class... U>
+ explicit(see-below) tuple(allocator_arg_t, const Alloc& a, const tuple<U...>&); // constexpr in C++20
+ template <class Alloc, class... U>
+ explicit(see-below) tuple(allocator_arg_t, const Alloc& a, tuple<U...>&&); // constexpr in C++20
+ template<class Alloc, class... UTypes>
+ constexpr explicit(see-below)
+ tuple(allocator_arg_t, const Alloc& a, const tuple<UTypes...>&&); // C++23
+ template<class Alloc, class U1, class U2>
+ constexpr explicit(see-below)
+ tuple(allocator_arg_t, const Alloc& a, pair<U1, U2>&); // C++23
+ template <class Alloc, class U1, class U2>
+ explicit(see-below) tuple(allocator_arg_t, const Alloc& a, const pair<U1, U2>&); // constexpr in C++20
+ template <class Alloc, class U1, class U2>
+ explicit(see-below) tuple(allocator_arg_t, const Alloc& a, pair<U1, U2>&&); // constexpr in C++20
+ template<class Alloc, class U1, class U2>
+ constexpr explicit(see-below)
+ tuple(allocator_arg_t, const Alloc& a, const pair<U1, U2>&&); // C++23
+
+ tuple& operator=(const tuple&); // constexpr in C++20
+ constexpr const tuple& operator=(const tuple&) const; // C++23
+ tuple& operator=(tuple&&) noexcept(is_nothrow_move_assignable_v<T> && ...); // constexpr in C++20
+ constexpr const tuple& operator=(tuple&&) const; // C++23
+ template <class... U>
+ tuple& operator=(const tuple<U...>&); // constexpr in C++20
+ template<class... UTypes>
+ constexpr const tuple& operator=(const tuple<UTypes...>&) const; // C++23
+ template <class... U>
+ tuple& operator=(tuple<U...>&&); // constexpr in C++20
+ template<class... UTypes>
+ constexpr const tuple& operator=(tuple<UTypes...>&&) const; // C++23
+ template <class U1, class U2>
+ tuple& operator=(const pair<U1, U2>&); // iff sizeof...(T) == 2 // constexpr in C++20
+ template<class U1, class U2>
+ constexpr const tuple& operator=(const pair<U1, U2>&) const; // iff sizeof...(Types) == 2 // C++23
+ template <class U1, class U2>
+ tuple& operator=(pair<U1, U2>&&); // iff sizeof...(T) == 2 // constexpr in C++20
+ template<class U1, class U2>
+ constexpr const tuple& operator=(pair<U1, U2>&&) const; // iff sizeof...(Types) == 2 // C++23
+
+ template<class U, size_t N>
+ tuple& operator=(array<U, N> const&) // iff sizeof...(T) == N, EXTENSION
+ template<class U, size_t N>
+ tuple& operator=(array<U, N>&&) // iff sizeof...(T) == N, EXTENSION
+
+ void swap(tuple&) noexcept(AND(swap(declval<T&>(), declval<T&>())...)); // constexpr in C++20
+ constexpr void swap(const tuple&) const noexcept(see-below); // C++23
+};
+
+
+template<class... TTypes, class... UTypes, template<class> class TQual, template<class> class UQual> // since C++23
+ requires requires { typename tuple<common_reference_t<TQual<TTypes>, UQual<UTypes>>...>; }
+struct basic_common_reference<tuple<TTypes...>, tuple<UTypes...>, TQual, UQual> {
+ using type = tuple<common_reference_t<TQual<TTypes>, UQual<UTypes>>...>;
+};
+
+template<class... TTypes, class... UTypes> // since C++23
+ requires requires { typename tuple<common_type_t<TTypes, UTypes>...>; }
+struct common_type<tuple<TTypes...>, tuple<UTypes...>> {
+ using type = tuple<common_type_t<TTypes, UTypes>...>;
+};
+
+template <class ...T>
+tuple(T...) -> tuple<T...>; // since C++17
+template <class T1, class T2>
+tuple(pair<T1, T2>) -> tuple<T1, T2>; // since C++17
+template <class Alloc, class ...T>
+tuple(allocator_arg_t, Alloc, T...) -> tuple<T...>; // since C++17
+template <class Alloc, class T1, class T2>
+tuple(allocator_arg_t, Alloc, pair<T1, T2>) -> tuple<T1, T2>; // since C++17
+template <class Alloc, class ...T>
+tuple(allocator_arg_t, Alloc, tuple<T...>) -> tuple<T...>; // since C++17
+
+struct ignore-type { // exposition only // Since C++26
+ constexpr const ignore-type&
+ operator=(const auto &) const noexcept
+ { return *this; }
+};
+inline constexpr ignore-type ignore;
+
+template <class... T> tuple<V...> make_tuple(T&&...); // constexpr in C++14
+template <class... T> tuple<ATypes...> forward_as_tuple(T&&...) noexcept; // constexpr in C++14
+template <class... T> tuple<T&...> tie(T&...) noexcept; // constexpr in C++14
+template <class... Tuples> tuple<CTypes...> tuple_cat(Tuples&&... tpls); // constexpr in C++14
+
+// [tuple.apply], calling a function with a tuple of arguments:
+template <class F, class Tuple>
+ constexpr decltype(auto) apply(F&& f, Tuple&& t) noexcept(see below); // C++17 noexcept since C++23
+template <class T, class Tuple>
+ constexpr T make_from_tuple(Tuple&& t); // C++17
+
+// 20.4.1.4, tuple helper classes:
+template <class T> struct tuple_size; // undefined
+template <class... T> struct tuple_size<tuple<T...>>;
+template <class T>
+ inline constexpr size_t tuple_size_v = tuple_size<T>::value; // C++17
+template <size_t I, class T> struct tuple_element; // undefined
+template <size_t I, class... T> struct tuple_element<I, tuple<T...>>;
+template <size_t I, class T>
+ using tuple_element_t = typename tuple_element <I, T>::type; // C++14
+
+// 20.4.1.5, element access:
+template <size_t I, class... T>
+ typename tuple_element<I, tuple<T...>>::type&
+ get(tuple<T...>&) noexcept; // constexpr in C++14
+template <size_t I, class... T>
+ const typename tuple_element<I, tuple<T...>>::type&
+ get(const tuple<T...>&) noexcept; // constexpr in C++14
+template <size_t I, class... T>
+ typename tuple_element<I, tuple<T...>>::type&&
+ get(tuple<T...>&&) noexcept; // constexpr in C++14
+template <size_t I, class... T>
+ const typename tuple_element<I, tuple<T...>>::type&&
+ get(const tuple<T...>&&) noexcept; // constexpr in C++14
+
+template <class T1, class... T>
+ constexpr T1& get(tuple<T...>&) noexcept; // C++14
+template <class T1, class... T>
+ constexpr const T1& get(const tuple<T...>&) noexcept; // C++14
+template <class T1, class... T>
+ constexpr T1&& get(tuple<T...>&&) noexcept; // C++14
+template <class T1, class... T>
+ constexpr const T1&& get(const tuple<T...>&&) noexcept; // C++14
+
+// 20.4.1.6, relational operators:
+template<class... T, class... U> bool operator==(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14
+template<class... T, class... U> bool operator<(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20
+template<class... T, class... U> bool operator!=(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20
+template<class... T, class... U> bool operator>(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20
+template<class... T, class... U> bool operator<=(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20
+template<class... T, class... U> bool operator>=(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20
+template<class... T, class... U>
+ constexpr common_comparison_category_t<synth-three-way-result<T, U>...>
+ operator<=>(const tuple<T...>&, const tuple<U...>&); // since C++20
+
+template <class... Types, class Alloc>
+ struct uses_allocator<tuple<Types...>, Alloc>;
+
+template <class... Types>
+ void
+ swap(tuple<Types...>& x, tuple<Types...>& y) noexcept(noexcept(x.swap(y)));
+
+template <class... Types>
+ constexpr void swap(const tuple<Types...>& x, const tuple<Types...>& y) noexcept(see-below); // C++23
+
+} // std
+
+*/
+
+// clang-format on
+
+#include <__compare/common_comparison_category.h>
+#include <__compare/synth_three_way.h>
+#include <__config>
+#include <__functional/invoke.h>
+#include <__fwd/array.h>
+#include <__fwd/pair.h>
+#include <__fwd/tuple.h>
+#include <__memory/allocator_arg_t.h>
+#include <__memory/uses_allocator.h>
+#include <__tuple/find_index.h>
+#include <__tuple/ignore.h>
+#include <__tuple/make_tuple_types.h>
+#include <__tuple/sfinae_helpers.h>
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_indices.h>
+#include <__tuple/tuple_like_ext.h>
+#include <__tuple/tuple_size.h>
+#include <__tuple/tuple_types.h>
+#include <__type_traits/common_reference.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/copy_cvref.h>
+#include <__type_traits/disjunction.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_empty.h>
+#include <__type_traits/is_final.h>
+#include <__type_traits/is_implicitly_default_constructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_swappable.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/lazy.h>
+#include <__type_traits/maybe_const.h>
+#include <__type_traits/nat.h>
+#include <__type_traits/negation.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_reference.h>
+#include <__type_traits/unwrap_ref.h>
+#include <__utility/forward.h>
+#include <__utility/integer_sequence.h>
+#include <__utility/move.h>
+#include <__utility/piecewise_construct.h>
+#include <__utility/swap.h>
+#include <cstddef>
+#include <version>
+
+// standard-mandated includes
+
+// [tuple.syn]
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifndef _LIBCPP_CXX03_LANG
+
+// __tuple_leaf
+
+template <size_t _Ip, class _Hp, bool = is_empty<_Hp>::value && !__libcpp_is_final<_Hp>::value >
+class __tuple_leaf;
+
+template <size_t _Ip, class _Hp, bool _Ep>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+swap(__tuple_leaf<_Ip, _Hp, _Ep>& __x, __tuple_leaf<_Ip, _Hp, _Ep>& __y) noexcept(__is_nothrow_swappable_v<_Hp>) {
+ swap(__x.get(), __y.get());
+}
+
+template <size_t _Ip, class _Hp, bool _Ep>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+swap(const __tuple_leaf<_Ip, _Hp, _Ep>& __x,
+ const __tuple_leaf<_Ip, _Hp, _Ep>& __y) noexcept(__is_nothrow_swappable_v<const _Hp>) {
+ swap(__x.get(), __y.get());
+}
+
+template <size_t _Ip, class _Hp, bool>
+class __tuple_leaf {
+ _Hp __value_;
+
+ template <class _Tp>
+ static _LIBCPP_HIDE_FROM_ABI constexpr bool __can_bind_reference() {
+# if __has_keyword(__reference_binds_to_temporary)
+ return !__reference_binds_to_temporary(_Hp, _Tp);
+# else
+ return true;
+# endif
+ }
+
+public:
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 __tuple_leaf& operator=(const __tuple_leaf&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf() noexcept(is_nothrow_default_constructible<_Hp>::value) : __value_() {
+ static_assert(!is_reference<_Hp>::value, "Attempted to default construct a reference element in a tuple");
+ }
+
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 0>, const _Alloc&) : __value_() {
+ static_assert(!is_reference<_Hp>::value, "Attempted to default construct a reference element in a tuple");
+ }
+
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a)
+ : __value_(allocator_arg_t(), __a) {
+ static_assert(!is_reference<_Hp>::value, "Attempted to default construct a reference element in a tuple");
+ }
+
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a) : __value_(__a) {
+ static_assert(!is_reference<_Hp>::value, "Attempted to default construct a reference element in a tuple");
+ }
+
+ template <
+ class _Tp,
+ __enable_if_t<_And<_IsNotSame<__remove_cvref_t<_Tp>, __tuple_leaf>, is_constructible<_Hp, _Tp> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(_Tp&& __t) noexcept(is_nothrow_constructible<_Hp, _Tp>::value)
+ : __value_(std::forward<_Tp>(__t)) {
+ static_assert(__can_bind_reference<_Tp&&>(),
+ "Attempted construction of reference element binds to a temporary whose lifetime has ended");
+ }
+
+ template <class _Tp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(integral_constant<int, 0>, const _Alloc&, _Tp&& __t)
+ : __value_(std::forward<_Tp>(__t)) {
+ static_assert(__can_bind_reference<_Tp&&>(),
+ "Attempted construction of reference element binds to a temporary whose lifetime has ended");
+ }
+
+ template <class _Tp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a, _Tp&& __t)
+ : __value_(allocator_arg_t(), __a, std::forward<_Tp>(__t)) {
+ static_assert(!is_reference<_Hp>::value, "Attempted to uses-allocator construct a reference element in a tuple");
+ }
+
+ template <class _Tp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a, _Tp&& __t)
+ : __value_(std::forward<_Tp>(__t), __a) {
+ static_assert(!is_reference<_Hp>::value, "Attempted to uses-allocator construct a reference element in a tuple");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __tuple_leaf(const __tuple_leaf& __t) = default;
+ _LIBCPP_HIDE_FROM_ABI __tuple_leaf(__tuple_leaf&& __t) = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int
+ swap(__tuple_leaf& __t) noexcept(__is_nothrow_swappable_v<__tuple_leaf>) {
+ std::swap(*this, __t);
+ return 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int swap(const __tuple_leaf& __t) const
+ noexcept(__is_nothrow_swappable_v<const __tuple_leaf>) {
+ std::swap(*this, __t);
+ return 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Hp& get() _NOEXCEPT { return __value_; }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Hp& get() const _NOEXCEPT { return __value_; }
+};
+
+template <size_t _Ip, class _Hp>
+class __tuple_leaf<_Ip, _Hp, true> : private _Hp {
+public:
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 __tuple_leaf& operator=(const __tuple_leaf&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf() noexcept(is_nothrow_default_constructible<_Hp>::value) {}
+
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 0>, const _Alloc&) {}
+
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a)
+ : _Hp(allocator_arg_t(), __a) {}
+
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a) : _Hp(__a) {}
+
+ template <class _Tp,
+ __enable_if_t< _And< _IsNotSame<__remove_cvref_t<_Tp>, __tuple_leaf>, is_constructible<_Hp, _Tp> >::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(_Tp&& __t) noexcept(is_nothrow_constructible<_Hp, _Tp>::value)
+ : _Hp(std::forward<_Tp>(__t)) {}
+
+ template <class _Tp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __tuple_leaf(integral_constant<int, 0>, const _Alloc&, _Tp&& __t)
+ : _Hp(std::forward<_Tp>(__t)) {}
+
+ template <class _Tp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a, _Tp&& __t)
+ : _Hp(allocator_arg_t(), __a, std::forward<_Tp>(__t)) {}
+
+ template <class _Tp, class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a, _Tp&& __t)
+ : _Hp(std::forward<_Tp>(__t), __a) {}
+
+ __tuple_leaf(__tuple_leaf const&) = default;
+ __tuple_leaf(__tuple_leaf&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int
+ swap(__tuple_leaf& __t) noexcept(__is_nothrow_swappable_v<__tuple_leaf>) {
+ std::swap(*this, __t);
+ return 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int swap(const __tuple_leaf& __rhs) const
+ noexcept(__is_nothrow_swappable_v<const __tuple_leaf>) {
+ std::swap(*this, __rhs);
+ return 0;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Hp& get() _NOEXCEPT { return static_cast<_Hp&>(*this); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Hp& get() const _NOEXCEPT {
+ return static_cast<const _Hp&>(*this);
+ }
+};
+
+template <class... _Tp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __swallow(_Tp&&...) _NOEXCEPT {}
+
+template <class _Tp>
+struct __all_default_constructible;
+
+template <class... _Tp>
+struct __all_default_constructible<__tuple_types<_Tp...>> : __all<is_default_constructible<_Tp>::value...> {};
+
+// __tuple_impl
+
+template <class _Indx, class... _Tp>
+struct __tuple_impl;
+
+template <size_t... _Indx, class... _Tp>
+struct _LIBCPP_DECLSPEC_EMPTY_BASES __tuple_impl<__tuple_indices<_Indx...>, _Tp...>
+ : public __tuple_leaf<_Indx, _Tp>... {
+ _LIBCPP_HIDE_FROM_ABI constexpr __tuple_impl() noexcept(
+ __all<is_nothrow_default_constructible<_Tp>::value...>::value) {}
+
+ template <size_t... _Uf, class... _Tf, size_t... _Ul, class... _Tl, class... _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_impl(
+ __tuple_indices<_Uf...>,
+ __tuple_types<_Tf...>,
+ __tuple_indices<_Ul...>,
+ __tuple_types<_Tl...>,
+ _Up&&... __u) noexcept(__all<is_nothrow_constructible<_Tf, _Up>::value...>::value &&
+ __all<is_nothrow_default_constructible<_Tl>::value...>::value)
+ : __tuple_leaf<_Uf, _Tf>(std::forward<_Up>(__u))..., __tuple_leaf<_Ul, _Tl>()... {}
+
+ template <class _Alloc, size_t... _Uf, class... _Tf, size_t... _Ul, class... _Tl, class... _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_impl(
+ allocator_arg_t,
+ const _Alloc& __a,
+ __tuple_indices<_Uf...>,
+ __tuple_types<_Tf...>,
+ __tuple_indices<_Ul...>,
+ __tuple_types<_Tl...>,
+ _Up&&... __u)
+ : __tuple_leaf<_Uf, _Tf>(__uses_alloc_ctor<_Tf, _Alloc, _Up>(), __a, std::forward<_Up>(__u))...,
+ __tuple_leaf<_Ul, _Tl>(__uses_alloc_ctor<_Tl, _Alloc>(), __a)... {}
+
+ template <class _Tuple, __enable_if_t<__tuple_constructible<_Tuple, tuple<_Tp...> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __tuple_impl(_Tuple&& __t) noexcept(
+ (__all<is_nothrow_constructible<
+ _Tp,
+ typename tuple_element<_Indx, typename __make_tuple_types<_Tuple>::type>::type>::value...>::value))
+ : __tuple_leaf<_Indx, _Tp>(
+ std::forward<typename tuple_element<_Indx, typename __make_tuple_types<_Tuple>::type>::type>(
+ std::get<_Indx>(__t)))... {}
+
+ template <class _Alloc, class _Tuple, __enable_if_t<__tuple_constructible<_Tuple, tuple<_Tp...> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __tuple_impl(allocator_arg_t, const _Alloc& __a, _Tuple&& __t)
+ : __tuple_leaf<_Indx, _Tp>(
+ __uses_alloc_ctor<_Tp,
+ _Alloc,
+ typename tuple_element<_Indx, typename __make_tuple_types<_Tuple>::type>::type>(),
+ __a,
+ std::forward<typename tuple_element<_Indx, typename __make_tuple_types<_Tuple>::type>::type>(
+ std::get<_Indx>(__t)))... {}
+
+ __tuple_impl(const __tuple_impl&) = default;
+ __tuple_impl(__tuple_impl&&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+ swap(__tuple_impl& __t) noexcept(__all<__is_nothrow_swappable_v<_Tp>...>::value) {
+ std::__swallow(__tuple_leaf<_Indx, _Tp>::swap(static_cast<__tuple_leaf<_Indx, _Tp>&>(__t))...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void swap(const __tuple_impl& __t) const
+ noexcept(__all<__is_nothrow_swappable_v<const _Tp>...>::value) {
+ std::__swallow(__tuple_leaf<_Indx, _Tp>::swap(static_cast<const __tuple_leaf<_Indx, _Tp>&>(__t))...);
+ }
+};
+
+template <class _Dest, class _Source, size_t... _Np>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__memberwise_copy_assign(_Dest& __dest, _Source const& __source, __tuple_indices<_Np...>) {
+ std::__swallow(((std::get<_Np>(__dest) = std::get<_Np>(__source)), void(), 0)...);
+}
+
+template <class _Dest, class _Source, class... _Up, size_t... _Np>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
+__memberwise_forward_assign(_Dest& __dest, _Source&& __source, __tuple_types<_Up...>, __tuple_indices<_Np...>) {
+ std::__swallow(((std::get<_Np>(__dest) = std::forward<_Up>(std::get<_Np>(__source))), void(), 0)...);
+}
+
+template <class... _Tp>
+class _LIBCPP_TEMPLATE_VIS tuple {
+ typedef __tuple_impl<typename __make_tuple_indices<sizeof...(_Tp)>::type, _Tp...> _BaseT;
+
+ _BaseT __base_;
+
+ template <size_t _Jp, class... _Up>
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Jp, tuple<_Up...> >::type& get(tuple<_Up...>&) _NOEXCEPT;
+ template <size_t _Jp, class... _Up>
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Jp, tuple<_Up...> >::type&
+ get(const tuple<_Up...>&) _NOEXCEPT;
+ template <size_t _Jp, class... _Up>
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Jp, tuple<_Up...> >::type&&
+ get(tuple<_Up...>&&) _NOEXCEPT;
+ template <size_t _Jp, class... _Up>
+ friend _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Jp, tuple<_Up...> >::type&&
+ get(const tuple<_Up...>&&) _NOEXCEPT;
+
+public:
+ using __trivially_relocatable = __conditional_t<_And<__libcpp_is_trivially_relocatable<_Tp>...>::value, tuple, void>;
+
+ // [tuple.cnstr]
+
+ // tuple() constructors (including allocator_arg_t variants)
+ template <template <class...> class _IsImpDefault = __is_implicitly_default_constructible,
+ template <class...> class _IsDefault = is_default_constructible,
+ __enable_if_t< _And< _IsDefault<_Tp>... >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(_Not<_Lazy<_And, _IsImpDefault<_Tp>...> >::value)
+ tuple() noexcept(_And<is_nothrow_default_constructible<_Tp>...>::value) {}
+
+ template <class _Alloc,
+ template <class...> class _IsImpDefault = __is_implicitly_default_constructible,
+ template <class...> class _IsDefault = is_default_constructible,
+ __enable_if_t< _And< _IsDefault<_Tp>... >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, _IsImpDefault<_Tp>...> >::value)
+ tuple(allocator_arg_t, _Alloc const& __a)
+ : __base_(allocator_arg_t(),
+ __a,
+ __tuple_indices<>(),
+ __tuple_types<>(),
+ typename __make_tuple_indices<sizeof...(_Tp), 0>::type(),
+ __tuple_types<_Tp...>()) {}
+
+ // tuple(const T&...) constructors (including allocator_arg_t variants)
+ template <template <class...> class _And = _And,
+ __enable_if_t< _And< _BoolConstant<sizeof...(_Tp) >= 1>, is_copy_constructible<_Tp>... >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_Lazy<_And, is_convertible<const _Tp&, _Tp>...> >::value)
+ tuple(const _Tp&... __t) noexcept(_And<is_nothrow_copy_constructible<_Tp>...>::value)
+ : __base_(typename __make_tuple_indices<sizeof...(_Tp)>::type(),
+ typename __make_tuple_types<tuple, sizeof...(_Tp)>::type(),
+ typename __make_tuple_indices<0>::type(),
+ typename __make_tuple_types<tuple, 0>::type(),
+ __t...) {}
+
+ template <class _Alloc,
+ template <class...> class _And = _And,
+ __enable_if_t< _And< _BoolConstant<sizeof...(_Tp) >= 1>, is_copy_constructible<_Tp>... >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, is_convertible<const _Tp&, _Tp>...> >::value)
+ tuple(allocator_arg_t, const _Alloc& __a, const _Tp&... __t)
+ : __base_(allocator_arg_t(),
+ __a,
+ typename __make_tuple_indices<sizeof...(_Tp)>::type(),
+ typename __make_tuple_types<tuple, sizeof...(_Tp)>::type(),
+ typename __make_tuple_indices<0>::type(),
+ typename __make_tuple_types<tuple, 0>::type(),
+ __t...) {}
+
+ // tuple(U&& ...) constructors (including allocator_arg_t variants)
+ template <class... _Up>
+ struct _IsThisTuple : false_type {};
+ template <class _Up>
+ struct _IsThisTuple<_Up> : is_same<__remove_cvref_t<_Up>, tuple> {};
+
+ template <class... _Up>
+ struct _EnableUTypesCtor
+ : _And< _BoolConstant<sizeof...(_Tp) >= 1>,
+ _Not<_IsThisTuple<_Up...> >, // extension to allow mis-behaved user constructors
+ is_constructible<_Tp, _Up>... > {};
+
+ template <class... _Up,
+ __enable_if_t< _And< _BoolConstant<sizeof...(_Up) == sizeof...(_Tp)>, _EnableUTypesCtor<_Up...> >::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_Lazy<_And, is_convertible<_Up, _Tp>...> >::value)
+ tuple(_Up&&... __u) noexcept(_And<is_nothrow_constructible<_Tp, _Up>...>::value)
+ : __base_(typename __make_tuple_indices<sizeof...(_Up)>::type(),
+ typename __make_tuple_types<tuple, sizeof...(_Up)>::type(),
+ typename __make_tuple_indices<sizeof...(_Tp), sizeof...(_Up)>::type(),
+ typename __make_tuple_types<tuple, sizeof...(_Tp), sizeof...(_Up)>::type(),
+ std::forward<_Up>(__u)...) {}
+
+ template <class _Alloc,
+ class... _Up,
+ __enable_if_t< _And< _BoolConstant<sizeof...(_Up) == sizeof...(_Tp)>, _EnableUTypesCtor<_Up...> >::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, is_convertible<_Up, _Tp>...> >::value)
+ tuple(allocator_arg_t, const _Alloc& __a, _Up&&... __u)
+ : __base_(allocator_arg_t(),
+ __a,
+ typename __make_tuple_indices<sizeof...(_Up)>::type(),
+ typename __make_tuple_types<tuple, sizeof...(_Up)>::type(),
+ typename __make_tuple_indices<sizeof...(_Tp), sizeof...(_Up)>::type(),
+ typename __make_tuple_types<tuple, sizeof...(_Tp), sizeof...(_Up)>::type(),
+ std::forward<_Up>(__u)...) {}
+
+ // Copy and move constructors (including the allocator_arg_t variants)
+ tuple(const tuple&) = default;
+ tuple(tuple&&) = default;
+
+ template <class _Alloc,
+ template <class...> class _And = _And,
+ __enable_if_t< _And<is_copy_constructible<_Tp>...>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc& __alloc, const tuple& __t)
+ : __base_(allocator_arg_t(), __alloc, __t) {}
+
+ template <class _Alloc,
+ template <class...> class _And = _And,
+ __enable_if_t< _And<is_move_constructible<_Tp>...>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc& __alloc, tuple&& __t)
+ : __base_(allocator_arg_t(), __alloc, std::move(__t)) {}
+
+ // tuple(const tuple<U...>&) constructors (including allocator_arg_t variants)
+
+ template <class _OtherTuple, class _DecayedOtherTuple = __remove_cvref_t<_OtherTuple>, class = void>
+ struct _EnableCtorFromUTypesTuple : false_type {};
+
+ template <class _OtherTuple, class... _Up>
+ struct _EnableCtorFromUTypesTuple<
+ _OtherTuple,
+ tuple<_Up...>,
+ // the length of the packs needs to checked first otherwise the 2 packs cannot be expanded simultaneously below
+ __enable_if_t<sizeof...(_Up) == sizeof...(_Tp)>>
+ : _And<
+ // the two conditions below are not in spec. The purpose is to disable the UTypes Ctor when copy/move Ctor
+ // can work. Otherwise, is_constructible can trigger hard error in those cases
+ // https://godbolt.org/z/M94cGdKcE
+ _Not<is_same<_OtherTuple, const tuple&> >,
+ _Not<is_same<_OtherTuple, tuple&&> >,
+ is_constructible<_Tp, __copy_cvref_t<_OtherTuple, _Up> >...,
+ _Lazy<_Or,
+ _BoolConstant<sizeof...(_Tp) != 1>,
+ // _Tp and _Up are 1-element packs - the pack expansions look
+ // weird to avoid tripping up the type traits in degenerate cases
+ _Lazy<_And,
+ _Not<is_same<_Tp, _Up> >...,
+ _Not<is_convertible<_OtherTuple, _Tp> >...,
+ _Not<is_constructible<_Tp, _OtherTuple> >... > > > {};
+
+ template <class... _Up, __enable_if_t< _And< _EnableCtorFromUTypesTuple<const tuple<_Up...>&> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_Lazy<_And, is_convertible<const _Up&, _Tp>...> >::value)
+ tuple(const tuple<_Up...>& __t) noexcept(_And<is_nothrow_constructible<_Tp, const _Up&>...>::value)
+ : __base_(__t) {}
+
+ template <class... _Up,
+ class _Alloc,
+ __enable_if_t< _And< _EnableCtorFromUTypesTuple<const tuple<_Up...>&> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, is_convertible<const _Up&, _Tp>...> >::value)
+ tuple(allocator_arg_t, const _Alloc& __a, const tuple<_Up...>& __t)
+ : __base_(allocator_arg_t(), __a, __t) {}
+
+# if _LIBCPP_STD_VER >= 23
+ // tuple(tuple<U...>&) constructors (including allocator_arg_t variants)
+
+ template <class... _Up, enable_if_t< _EnableCtorFromUTypesTuple<tuple<_Up...>&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_Lazy<_And, is_convertible<_Up&, _Tp>...>::value) tuple(tuple<_Up...>& __t)
+ : __base_(__t) {}
+
+ template <class _Alloc, class... _Up, enable_if_t< _EnableCtorFromUTypesTuple<tuple<_Up...>&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_Lazy<_And, is_convertible<_Up&, _Tp>...>::value)
+ tuple(allocator_arg_t, const _Alloc& __alloc, tuple<_Up...>& __t)
+ : __base_(allocator_arg_t(), __alloc, __t) {}
+# endif // _LIBCPP_STD_VER >= 23
+
+ // tuple(tuple<U...>&&) constructors (including allocator_arg_t variants)
+ template <class... _Up, __enable_if_t< _And< _EnableCtorFromUTypesTuple<tuple<_Up...>&&> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_Lazy<_And, is_convertible<_Up, _Tp>...> >::value)
+ tuple(tuple<_Up...>&& __t) noexcept(_And<is_nothrow_constructible<_Tp, _Up>...>::value)
+ : __base_(std::move(__t)) {}
+
+ template <class _Alloc,
+ class... _Up,
+ __enable_if_t< _And< _EnableCtorFromUTypesTuple<tuple<_Up...>&&> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, is_convertible<_Up, _Tp>...> >::value)
+ tuple(allocator_arg_t, const _Alloc& __a, tuple<_Up...>&& __t)
+ : __base_(allocator_arg_t(), __a, std::move(__t)) {}
+
+# if _LIBCPP_STD_VER >= 23
+ // tuple(const tuple<U...>&&) constructors (including allocator_arg_t variants)
+
+ template <class... _Up, enable_if_t< _EnableCtorFromUTypesTuple<const tuple<_Up...>&&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_Lazy<_And, is_convertible<const _Up&&, _Tp>...>::value)
+ tuple(const tuple<_Up...>&& __t)
+ : __base_(std::move(__t)) {}
+
+ template <class _Alloc,
+ class... _Up,
+ enable_if_t< _EnableCtorFromUTypesTuple<const tuple<_Up...>&&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_Lazy<_And, is_convertible<const _Up&&, _Tp>...>::value)
+ tuple(allocator_arg_t, const _Alloc& __alloc, const tuple<_Up...>&& __t)
+ : __base_(allocator_arg_t(), __alloc, std::move(__t)) {}
+# endif // _LIBCPP_STD_VER >= 23
+
+ // tuple(const pair<U1, U2>&) constructors (including allocator_arg_t variants)
+
+ template <template <class...> class _Pred,
+ class _Pair,
+ class _DecayedPair = __remove_cvref_t<_Pair>,
+ class _Tuple = tuple>
+ struct _CtorPredicateFromPair : false_type {};
+
+ template <template <class...> class _Pred, class _Pair, class _Up1, class _Up2, class _Tp1, class _Tp2>
+ struct _CtorPredicateFromPair<_Pred, _Pair, pair<_Up1, _Up2>, tuple<_Tp1, _Tp2> >
+ : _And< _Pred<_Tp1, __copy_cvref_t<_Pair, _Up1> >, _Pred<_Tp2, __copy_cvref_t<_Pair, _Up2> > > {};
+
+ template <class _Pair>
+ struct _EnableCtorFromPair : _CtorPredicateFromPair<is_constructible, _Pair> {};
+
+ template <class _Pair>
+ struct _NothrowConstructibleFromPair : _CtorPredicateFromPair<is_nothrow_constructible, _Pair> {};
+
+ template <class _Pair, class _DecayedPair = __remove_cvref_t<_Pair>, class _Tuple = tuple>
+ struct _BothImplicitlyConvertible : false_type {};
+
+ template <class _Pair, class _Up1, class _Up2, class _Tp1, class _Tp2>
+ struct _BothImplicitlyConvertible<_Pair, pair<_Up1, _Up2>, tuple<_Tp1, _Tp2> >
+ : _And< is_convertible<__copy_cvref_t<_Pair, _Up1>, _Tp1>, is_convertible<__copy_cvref_t<_Pair, _Up2>, _Tp2> > {};
+
+ template <class _Up1,
+ class _Up2,
+ template <class...> class _And = _And,
+ __enable_if_t< _And< _EnableCtorFromPair<const pair<_Up1, _Up2>&> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_BothImplicitlyConvertible<const pair<_Up1, _Up2>&> >::value)
+ tuple(const pair<_Up1, _Up2>& __p) noexcept(_NothrowConstructibleFromPair<const pair<_Up1, _Up2>&>::value)
+ : __base_(__p) {}
+
+ template <class _Alloc,
+ class _Up1,
+ class _Up2,
+ template <class...> class _And = _And,
+ __enable_if_t< _And< _EnableCtorFromPair<const pair<_Up1, _Up2>&> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_BothImplicitlyConvertible<const pair<_Up1, _Up2>&> >::value)
+ tuple(allocator_arg_t, const _Alloc& __a, const pair<_Up1, _Up2>& __p)
+ : __base_(allocator_arg_t(), __a, __p) {}
+
+# if _LIBCPP_STD_VER >= 23
+ // tuple(pair<U1, U2>&) constructors (including allocator_arg_t variants)
+
+ template <class _U1, class _U2, enable_if_t< _EnableCtorFromPair<pair<_U1, _U2>&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_BothImplicitlyConvertible<pair<_U1, _U2>&>::value)
+ tuple(pair<_U1, _U2>& __p)
+ : __base_(__p) {}
+
+ template <class _Alloc,
+ class _U1,
+ class _U2,
+ enable_if_t< _EnableCtorFromPair<std::pair<_U1, _U2>&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_BothImplicitlyConvertible<pair<_U1, _U2>&>::value)
+ tuple(allocator_arg_t, const _Alloc& __alloc, pair<_U1, _U2>& __p)
+ : __base_(allocator_arg_t(), __alloc, __p) {}
+# endif
+
+ // tuple(pair<U1, U2>&&) constructors (including allocator_arg_t variants)
+
+ template <class _Up1,
+ class _Up2,
+ template <class...> class _And = _And,
+ __enable_if_t< _And< _EnableCtorFromPair<pair<_Up1, _Up2>&&> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_BothImplicitlyConvertible<pair<_Up1, _Up2>&&> >::value)
+ tuple(pair<_Up1, _Up2>&& __p) noexcept(_NothrowConstructibleFromPair<pair<_Up1, _Up2>&&>::value)
+ : __base_(std::move(__p)) {}
+
+ template <class _Alloc,
+ class _Up1,
+ class _Up2,
+ template <class...> class _And = _And,
+ __enable_if_t< _And< _EnableCtorFromPair<pair<_Up1, _Up2>&&> >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_BothImplicitlyConvertible<pair<_Up1, _Up2>&&> >::value)
+ tuple(allocator_arg_t, const _Alloc& __a, pair<_Up1, _Up2>&& __p)
+ : __base_(allocator_arg_t(), __a, std::move(__p)) {}
+
+# if _LIBCPP_STD_VER >= 23
+ // tuple(const pair<U1, U2>&&) constructors (including allocator_arg_t variants)
+
+ template <class _U1, class _U2, enable_if_t< _EnableCtorFromPair<const pair<_U1, _U2>&&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_BothImplicitlyConvertible<const pair<_U1, _U2>&&>::value)
+ tuple(const pair<_U1, _U2>&& __p)
+ : __base_(std::move(__p)) {}
+
+ template <class _Alloc,
+ class _U1,
+ class _U2,
+ enable_if_t< _EnableCtorFromPair<const pair<_U1, _U2>&&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_BothImplicitlyConvertible<const pair<_U1, _U2>&&>::value)
+ tuple(allocator_arg_t, const _Alloc& __alloc, const pair<_U1, _U2>&& __p)
+ : __base_(allocator_arg_t(), __alloc, std::move(__p)) {}
+# endif // _LIBCPP_STD_VER >= 23
+
+ // [tuple.assign]
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&
+ operator=(_If<_And<is_copy_assignable<_Tp>...>::value, tuple, __nat> const& __tuple)
+ noexcept(_And<is_nothrow_copy_assignable<_Tp>...>::value) {
+ std::__memberwise_copy_assign(*this, __tuple, typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(tuple const& __tuple) const
+ requires(_And<is_copy_assignable<const _Tp>...>::value)
+ {
+ std::__memberwise_copy_assign(*this, __tuple, typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(tuple&& __tuple) const
+ requires(_And<is_assignable<const _Tp&, _Tp>...>::value)
+ {
+ std::__memberwise_forward_assign(
+ *this, std::move(__tuple), __tuple_types<_Tp...>(), typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+# endif // _LIBCPP_STD_VER >= 23
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&
+ operator=(_If<_And<is_move_assignable<_Tp>...>::value, tuple, __nat>&& __tuple)
+ noexcept(_And<is_nothrow_move_assignable<_Tp>...>::value) {
+ std::__memberwise_forward_assign(
+ *this, std::move(__tuple), __tuple_types<_Tp...>(), typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+
+ template <
+ class... _Up,
+ __enable_if_t< _And< _BoolConstant<sizeof...(_Tp) == sizeof...(_Up)>, is_assignable<_Tp&, _Up const&>... >::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple& operator=(tuple<_Up...> const& __tuple)
+ noexcept(_And<is_nothrow_assignable<_Tp&, _Up const&>...>::value) {
+ std::__memberwise_copy_assign(*this, __tuple, typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+
+ template <class... _Up,
+ __enable_if_t< _And< _BoolConstant<sizeof...(_Tp) == sizeof...(_Up)>, is_assignable<_Tp&, _Up>... >::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple& operator=(tuple<_Up...>&& __tuple)
+ noexcept(_And<is_nothrow_assignable<_Tp&, _Up>...>::value) {
+ std::__memberwise_forward_assign(
+ *this, std::move(__tuple), __tuple_types<_Up...>(), typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ template <class... _UTypes,
+ enable_if_t< _And<_BoolConstant<sizeof...(_Tp) == sizeof...(_UTypes)>,
+ is_assignable<const _Tp&, const _UTypes&>...>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(const tuple<_UTypes...>& __u) const {
+ std::__memberwise_copy_assign(*this, __u, typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+
+ template <class... _UTypes,
+ enable_if_t< _And<_BoolConstant<sizeof...(_Tp) == sizeof...(_UTypes)>,
+ is_assignable<const _Tp&, _UTypes>...>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(tuple<_UTypes...>&& __u) const {
+ std::__memberwise_forward_assign(
+ *this, __u, __tuple_types<_UTypes...>(), typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+# endif // _LIBCPP_STD_VER >= 23
+
+ template <template <class...> class _Pred,
+ bool _Const,
+ class _Pair,
+ class _DecayedPair = __remove_cvref_t<_Pair>,
+ class _Tuple = tuple>
+ struct _AssignPredicateFromPair : false_type {};
+
+ template <template <class...> class _Pred, bool _Const, class _Pair, class _Up1, class _Up2, class _Tp1, class _Tp2>
+ struct _AssignPredicateFromPair<_Pred, _Const, _Pair, pair<_Up1, _Up2>, tuple<_Tp1, _Tp2> >
+ : _And<_Pred<__maybe_const<_Const, _Tp1>&, __copy_cvref_t<_Pair, _Up1> >,
+ _Pred<__maybe_const<_Const, _Tp2>&, __copy_cvref_t<_Pair, _Up2> > > {};
+
+ template <bool _Const, class _Pair>
+ struct _EnableAssignFromPair : _AssignPredicateFromPair<is_assignable, _Const, _Pair> {};
+
+ template <bool _Const, class _Pair>
+ struct _NothrowAssignFromPair : _AssignPredicateFromPair<is_nothrow_assignable, _Const, _Pair> {};
+
+# if _LIBCPP_STD_VER >= 23
+ template <class _U1, class _U2, enable_if_t< _EnableAssignFromPair<true, const pair<_U1, _U2>&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(const pair<_U1, _U2>& __pair) const
+ noexcept(_NothrowAssignFromPair<true, const pair<_U1, _U2>&>::value) {
+ std::get<0>(*this) = __pair.first;
+ std::get<1>(*this) = __pair.second;
+ return *this;
+ }
+
+ template <class _U1, class _U2, enable_if_t< _EnableAssignFromPair<true, pair<_U1, _U2>&&>::value>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(pair<_U1, _U2>&& __pair) const
+ noexcept(_NothrowAssignFromPair<true, pair<_U1, _U2>&&>::value) {
+ std::get<0>(*this) = std::move(__pair.first);
+ std::get<1>(*this) = std::move(__pair.second);
+ return *this;
+ }
+# endif // _LIBCPP_STD_VER >= 23
+
+ template <class _Up1,
+ class _Up2,
+ __enable_if_t< _EnableAssignFromPair<false, pair<_Up1, _Up2> const&>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple& operator=(pair<_Up1, _Up2> const& __pair)
+ noexcept(_NothrowAssignFromPair<false, pair<_Up1, _Up2> const&>::value) {
+ std::get<0>(*this) = __pair.first;
+ std::get<1>(*this) = __pair.second;
+ return *this;
+ }
+
+ template <class _Up1, class _Up2, __enable_if_t< _EnableAssignFromPair<false, pair<_Up1, _Up2>&&>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple& operator=(pair<_Up1, _Up2>&& __pair)
+ noexcept(_NothrowAssignFromPair<false, pair<_Up1, _Up2>&&>::value) {
+ std::get<0>(*this) = std::forward<_Up1>(__pair.first);
+ std::get<1>(*this) = std::forward<_Up2>(__pair.second);
+ return *this;
+ }
+
+ // EXTENSION
+ template <
+ class _Up,
+ size_t _Np,
+ __enable_if_t< _And< _BoolConstant<_Np == sizeof...(_Tp)>, is_assignable<_Tp&, _Up const&>... >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple& operator=(array<_Up, _Np> const& __array)
+ noexcept(_And<is_nothrow_assignable<_Tp&, _Up const&>...>::value) {
+ std::__memberwise_copy_assign(*this, __array, typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+
+ // EXTENSION
+ template <class _Up,
+ size_t _Np,
+ class = void,
+ __enable_if_t< _And< _BoolConstant<_Np == sizeof...(_Tp)>, is_assignable<_Tp&, _Up>... >::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple& operator=(array<_Up, _Np>&& __array)
+ noexcept(_And<is_nothrow_assignable<_Tp&, _Up>...>::value) {
+ std::__memberwise_forward_assign(
+ *this,
+ std::move(__array),
+ __tuple_types<_If<true, _Up, _Tp>...>(),
+ typename __make_tuple_indices<sizeof...(_Tp)>::type());
+ return *this;
+ }
+
+ // [tuple.swap]
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(tuple& __t)
+ noexcept(__all<__is_nothrow_swappable_v<_Tp>...>::value) {
+ __base_.swap(__t.__base_);
+ }
+
+# if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI constexpr void swap(const tuple& __t) const
+ noexcept(__all<is_nothrow_swappable_v<const _Tp&>...>::value) {
+ __base_.swap(__t.__base_);
+ }
+# endif // _LIBCPP_STD_VER >= 23
+};
+
+template <>
+class _LIBCPP_TEMPLATE_VIS tuple<> {
+public:
+ constexpr tuple() _NOEXCEPT = default;
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc&) _NOEXCEPT {}
+ template <class _Alloc>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc&, const tuple&) _NOEXCEPT {}
+ template <class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(array<_Up, 0>) _NOEXCEPT {}
+ template <class _Alloc, class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc&, array<_Up, 0>) _NOEXCEPT {}
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(tuple&) _NOEXCEPT {}
+# if _LIBCPP_STD_VER >= 23
+ _LIBCPP_HIDE_FROM_ABI constexpr void swap(const tuple&) const noexcept {}
+# endif
+};
+
+# if _LIBCPP_STD_VER >= 23
+template <class... _TTypes, class... _UTypes, template <class> class _TQual, template <class> class _UQual>
+ requires requires { typename tuple<common_reference_t<_TQual<_TTypes>, _UQual<_UTypes>>...>; }
+struct basic_common_reference<tuple<_TTypes...>, tuple<_UTypes...>, _TQual, _UQual> {
+ using type = tuple<common_reference_t<_TQual<_TTypes>, _UQual<_UTypes>>...>;
+};
+
+template <class... _TTypes, class... _UTypes>
+ requires requires { typename tuple<common_type_t<_TTypes, _UTypes>...>; }
+struct common_type<tuple<_TTypes...>, tuple<_UTypes...>> {
+ using type = tuple<common_type_t<_TTypes, _UTypes>...>;
+};
+# endif // _LIBCPP_STD_VER >= 23
+
+# if _LIBCPP_STD_VER >= 17
+template <class... _Tp>
+tuple(_Tp...) -> tuple<_Tp...>;
+template <class _Tp1, class _Tp2>
+tuple(pair<_Tp1, _Tp2>) -> tuple<_Tp1, _Tp2>;
+template <class _Alloc, class... _Tp>
+tuple(allocator_arg_t, _Alloc, _Tp...) -> tuple<_Tp...>;
+template <class _Alloc, class _Tp1, class _Tp2>
+tuple(allocator_arg_t, _Alloc, pair<_Tp1, _Tp2>) -> tuple<_Tp1, _Tp2>;
+template <class _Alloc, class... _Tp>
+tuple(allocator_arg_t, _Alloc, tuple<_Tp...>) -> tuple<_Tp...>;
+# endif
+
+template <class... _Tp, __enable_if_t<__all<__is_swappable_v<_Tp>...>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(tuple<_Tp...>& __t, tuple<_Tp...>& __u)
+ noexcept(__all<__is_nothrow_swappable_v<_Tp>...>::value) {
+ __t.swap(__u);
+}
+
+# if _LIBCPP_STD_VER >= 23
+template <class... _Tp>
+_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<__all<is_swappable_v<const _Tp>...>::value, void>
+swap(const tuple<_Tp...>& __lhs,
+ const tuple<_Tp...>& __rhs) noexcept(__all<is_nothrow_swappable_v<const _Tp>...>::value) {
+ __lhs.swap(__rhs);
+}
+# endif
+
+// get
+
+template <size_t _Ip, class... _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, tuple<_Tp...> >::type&
+get(tuple<_Tp...>& __t) _NOEXCEPT {
+ typedef _LIBCPP_NODEBUG typename tuple_element<_Ip, tuple<_Tp...> >::type type;
+ return static_cast<__tuple_leaf<_Ip, type>&>(__t.__base_).get();
+}
+
+template <size_t _Ip, class... _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, tuple<_Tp...> >::type&
+get(const tuple<_Tp...>& __t) _NOEXCEPT {
+ typedef _LIBCPP_NODEBUG typename tuple_element<_Ip, tuple<_Tp...> >::type type;
+ return static_cast<const __tuple_leaf<_Ip, type>&>(__t.__base_).get();
+}
+
+template <size_t _Ip, class... _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, tuple<_Tp...> >::type&&
+get(tuple<_Tp...>&& __t) _NOEXCEPT {
+ typedef _LIBCPP_NODEBUG typename tuple_element<_Ip, tuple<_Tp...> >::type type;
+ return static_cast<type&&>(static_cast<__tuple_leaf<_Ip, type>&&>(__t.__base_).get());
+}
+
+template <size_t _Ip, class... _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, tuple<_Tp...> >::type&&
+get(const tuple<_Tp...>&& __t) _NOEXCEPT {
+ typedef _LIBCPP_NODEBUG typename tuple_element<_Ip, tuple<_Tp...> >::type type;
+ return static_cast<const type&&>(static_cast<const __tuple_leaf<_Ip, type>&&>(__t.__base_).get());
+}
+
+# if _LIBCPP_STD_VER >= 14
+
+template <class _T1, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1& get(tuple<_Args...>& __tup) noexcept {
+ return std::get<__find_exactly_one_t<_T1, _Args...>::value>(__tup);
+}
+
+template <class _T1, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1 const& get(tuple<_Args...> const& __tup) noexcept {
+ return std::get<__find_exactly_one_t<_T1, _Args...>::value>(__tup);
+}
+
+template <class _T1, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1&& get(tuple<_Args...>&& __tup) noexcept {
+ return std::get<__find_exactly_one_t<_T1, _Args...>::value>(std::move(__tup));
+}
+
+template <class _T1, class... _Args>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _T1 const&& get(tuple<_Args...> const&& __tup) noexcept {
+ return std::get<__find_exactly_one_t<_T1, _Args...>::value>(std::move(__tup));
+}
+
+# endif
+
+// tie
+
+template <class... _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 tuple<_Tp&...> tie(_Tp&... __t) _NOEXCEPT {
+ return tuple<_Tp&...>(__t...);
+}
+
+template <class... _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 tuple<typename __unwrap_ref_decay<_Tp>::type...>
+make_tuple(_Tp&&... __t) {
+ return tuple<typename __unwrap_ref_decay<_Tp>::type...>(std::forward<_Tp>(__t)...);
+}
+
+template <class... _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 tuple<_Tp&&...> forward_as_tuple(_Tp&&... __t) _NOEXCEPT {
+ return tuple<_Tp&&...>(std::forward<_Tp>(__t)...);
+}
+
+template <size_t _Ip>
+struct __tuple_equal {
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _Tp& __x, const _Up& __y) {
+ return __tuple_equal<_Ip - 1>()(__x, __y) && std::get<_Ip - 1>(__x) == std::get<_Ip - 1>(__y);
+ }
+};
+
+template <>
+struct __tuple_equal<0> {
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _Tp&, const _Up&) {
+ return true;
+ }
+};
+
+template <class... _Tp, class... _Up>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator==(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {
+ static_assert(sizeof...(_Tp) == sizeof...(_Up), "Can't compare tuples of different sizes");
+ return __tuple_equal<sizeof...(_Tp)>()(__x, __y);
+}
+
+# if _LIBCPP_STD_VER >= 20
+
+// operator<=>
+
+template <class... _Tp, class... _Up, size_t... _Is>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__tuple_compare_three_way(const tuple<_Tp...>& __x, const tuple<_Up...>& __y, index_sequence<_Is...>) {
+ common_comparison_category_t<__synth_three_way_result<_Tp, _Up>...> __result = strong_ordering::equal;
+ static_cast<void>(
+ ((__result = std::__synth_three_way(std::get<_Is>(__x), std::get<_Is>(__y)), __result != 0) || ...));
+ return __result;
+}
+
+template <class... _Tp, class... _Up>
+ requires(sizeof...(_Tp) == sizeof...(_Up))
+_LIBCPP_HIDE_FROM_ABI constexpr common_comparison_category_t<__synth_three_way_result<_Tp, _Up>...>
+operator<=>(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {
+ return std::__tuple_compare_three_way(__x, __y, index_sequence_for<_Tp...>{});
+}
+
+# else // _LIBCPP_STD_VER >= 20
+
+template <class... _Tp, class... _Up>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator!=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {
+ return !(__x == __y);
+}
+
+template <size_t _Ip>
+struct __tuple_less {
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _Tp& __x, const _Up& __y) {
+ const size_t __idx = tuple_size<_Tp>::value - _Ip;
+ if (std::get<__idx>(__x) < std::get<__idx>(__y))
+ return true;
+ if (std::get<__idx>(__y) < std::get<__idx>(__x))
+ return false;
+ return __tuple_less<_Ip - 1>()(__x, __y);
+ }
+};
+
+template <>
+struct __tuple_less<0> {
+ template <class _Tp, class _Up>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _Tp&, const _Up&) {
+ return false;
+ }
+};
+
+template <class... _Tp, class... _Up>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator<(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {
+ static_assert(sizeof...(_Tp) == sizeof...(_Up), "Can't compare tuples of different sizes");
+ return __tuple_less<sizeof...(_Tp)>()(__x, __y);
+}
+
+template <class... _Tp, class... _Up>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator>(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {
+ return __y < __x;
+}
+
+template <class... _Tp, class... _Up>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator>=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {
+ return !(__x < __y);
+}
+
+template <class... _Tp, class... _Up>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
+operator<=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {
+ return !(__y < __x);
+}
+
+# endif // _LIBCPP_STD_VER >= 20
+
+// tuple_cat
+
+template <class _Tp, class _Up>
+struct __tuple_cat_type;
+
+template <class... _Ttypes, class... _Utypes>
+struct __tuple_cat_type<tuple<_Ttypes...>, __tuple_types<_Utypes...> > {
+ typedef _LIBCPP_NODEBUG tuple<_Ttypes..., _Utypes...> type;
+};
+
+template <class _ResultTuple, bool _Is_Tuple0TupleLike, class... _Tuples>
+struct __tuple_cat_return_1 {};
+
+template <class... _Types, class _Tuple0>
+struct __tuple_cat_return_1<tuple<_Types...>, true, _Tuple0> {
+ using type _LIBCPP_NODEBUG =
+ typename __tuple_cat_type< tuple<_Types...>,
+ typename __make_tuple_types<__remove_cvref_t<_Tuple0> >::type >::type;
+};
+
+template <class... _Types, class _Tuple0, class _Tuple1, class... _Tuples>
+struct __tuple_cat_return_1<tuple<_Types...>, true, _Tuple0, _Tuple1, _Tuples...>
+ : public __tuple_cat_return_1<
+ typename __tuple_cat_type< tuple<_Types...>,
+ typename __make_tuple_types<__remove_cvref_t<_Tuple0> >::type >::type,
+ __tuple_like_ext<__libcpp_remove_reference_t<_Tuple1> >::value,
+ _Tuple1,
+ _Tuples...> {};
+
+template <class... _Tuples>
+struct __tuple_cat_return;
+
+template <class _Tuple0, class... _Tuples>
+struct __tuple_cat_return<_Tuple0, _Tuples...>
+ : public __tuple_cat_return_1<tuple<>,
+ __tuple_like_ext<__libcpp_remove_reference_t<_Tuple0> >::value,
+ _Tuple0,
+ _Tuples...> {};
+
+template <>
+struct __tuple_cat_return<> {
+ typedef _LIBCPP_NODEBUG tuple<> type;
+};
+
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 tuple<> tuple_cat() { return tuple<>(); }
+
+template <class _Rp, class _Indices, class _Tuple0, class... _Tuples>
+struct __tuple_cat_return_ref_imp;
+
+template <class... _Types, size_t... _I0, class _Tuple0>
+struct __tuple_cat_return_ref_imp<tuple<_Types...>, __tuple_indices<_I0...>, _Tuple0> {
+ typedef _LIBCPP_NODEBUG __libcpp_remove_reference_t<_Tuple0> _T0;
+ typedef tuple<_Types..., __copy_cvref_t<_Tuple0, typename tuple_element<_I0, _T0>::type>&&...> type;
+};
+
+template <class... _Types, size_t... _I0, class _Tuple0, class _Tuple1, class... _Tuples>
+struct __tuple_cat_return_ref_imp<tuple<_Types...>, __tuple_indices<_I0...>, _Tuple0, _Tuple1, _Tuples...>
+ : public __tuple_cat_return_ref_imp<
+ tuple<_Types...,
+ __copy_cvref_t<_Tuple0, typename tuple_element<_I0, __libcpp_remove_reference_t<_Tuple0>>::type>&&...>,
+ typename __make_tuple_indices<tuple_size<__libcpp_remove_reference_t<_Tuple1> >::value>::type,
+ _Tuple1,
+ _Tuples...> {};
+
+template <class _Tuple0, class... _Tuples>
+struct __tuple_cat_return_ref
+ : public __tuple_cat_return_ref_imp<
+ tuple<>,
+ typename __make_tuple_indices< tuple_size<__libcpp_remove_reference_t<_Tuple0> >::value >::type,
+ _Tuple0,
+ _Tuples...> {};
+
+template <class _Types, class _I0, class _J0>
+struct __tuple_cat;
+
+template <class... _Types, size_t... _I0, size_t... _J0>
+struct __tuple_cat<tuple<_Types...>, __tuple_indices<_I0...>, __tuple_indices<_J0...> > {
+ template <class _Tuple0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
+ typename __tuple_cat_return_ref<tuple<_Types...>&&, _Tuple0&&>::type
+ operator()(tuple<_Types...> __t, _Tuple0&& __t0) {
+ (void)__t; // avoid unused parameter warning on GCC when _I0 is empty
+ return std::forward_as_tuple(
+ std::forward<_Types>(std::get<_I0>(__t))..., std::get<_J0>(std::forward<_Tuple0>(__t0))...);
+ }
+
+ template <class _Tuple0, class _Tuple1, class... _Tuples>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
+ typename __tuple_cat_return_ref<tuple<_Types...>&&, _Tuple0&&, _Tuple1&&, _Tuples&&...>::type
+ operator()(tuple<_Types...> __t, _Tuple0&& __t0, _Tuple1&& __t1, _Tuples&&... __tpls) {
+ (void)__t; // avoid unused parameter warning on GCC when _I0 is empty
+ typedef _LIBCPP_NODEBUG __libcpp_remove_reference_t<_Tuple0> _T0;
+ typedef _LIBCPP_NODEBUG __libcpp_remove_reference_t<_Tuple1> _T1;
+ return __tuple_cat<tuple<_Types..., __copy_cvref_t<_Tuple0, typename tuple_element<_J0, _T0>::type>&&...>,
+ typename __make_tuple_indices<sizeof...(_Types) + tuple_size<_T0>::value>::type,
+ typename __make_tuple_indices<tuple_size<_T1>::value>::type>()(
+ std::forward_as_tuple(
+ std::forward<_Types>(std::get<_I0>(__t))..., std::get<_J0>(std::forward<_Tuple0>(__t0))...),
+ std::forward<_Tuple1>(__t1),
+ std::forward<_Tuples>(__tpls)...);
+ }
+};
+
+template <class _Tuple0, class... _Tuples>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename __tuple_cat_return<_Tuple0, _Tuples...>::type
+tuple_cat(_Tuple0&& __t0, _Tuples&&... __tpls) {
+ typedef _LIBCPP_NODEBUG __libcpp_remove_reference_t<_Tuple0> _T0;
+ return __tuple_cat<tuple<>, __tuple_indices<>, typename __make_tuple_indices<tuple_size<_T0>::value>::type>()(
+ tuple<>(), std::forward<_Tuple0>(__t0), std::forward<_Tuples>(__tpls)...);
+}
+
+template <class... _Tp, class _Alloc>
+struct _LIBCPP_TEMPLATE_VIS uses_allocator<tuple<_Tp...>, _Alloc> : true_type {};
+
+# if _LIBCPP_STD_VER >= 17
+# define _LIBCPP_NOEXCEPT_RETURN(...) \
+ noexcept(noexcept(__VA_ARGS__)) { return __VA_ARGS__; }
+
+// The _LIBCPP_NOEXCEPT_RETURN macro breaks formatting.
+// clang-format off
+template <class _Fn, class _Tuple, size_t... _Id>
+inline _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto)
+__apply_tuple_impl(_Fn&& __f, _Tuple&& __t, __tuple_indices<_Id...>)
+ _LIBCPP_NOEXCEPT_RETURN(std::__invoke(std::forward<_Fn>(__f), std::get<_Id>(std::forward<_Tuple>(__t))...))
+
+template <class _Fn, class _Tuple>
+inline _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) apply(_Fn&& __f, _Tuple&& __t)
+ _LIBCPP_NOEXCEPT_RETURN(std::__apply_tuple_impl(
+ std::forward<_Fn>(__f),
+ std::forward<_Tuple>(__t),
+ typename __make_tuple_indices<tuple_size_v<remove_reference_t<_Tuple>>>::type{}))
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Tuple, size_t... _Idx>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp __make_from_tuple_impl(_Tuple&& __t, __tuple_indices<_Idx...>)
+ noexcept(noexcept(_Tp(std::get<_Idx>(std::forward<_Tuple>(__t))...)))
+ requires is_constructible_v<_Tp, decltype(std::get<_Idx>(std::forward<_Tuple>(__t)))...> {
+ return _Tp(std::get<_Idx>(std::forward<_Tuple>(__t))...);
+}
+#else
+template <class _Tp, class _Tuple, size_t... _Idx>
+inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp __make_from_tuple_impl(_Tuple&& __t, __tuple_indices<_Idx...>,
+ enable_if_t<is_constructible_v<_Tp, decltype(std::get<_Idx>(std::forward<_Tuple>(__t)))...>> * = nullptr)
+ _LIBCPP_NOEXCEPT_RETURN(_Tp(std::get<_Idx>(std::forward<_Tuple>(__t))...))
+#endif // _LIBCPP_STD_VER >= 20
+
+template <class _Tp, class _Tuple,
+ class _Seq = typename __make_tuple_indices<tuple_size_v<remove_reference_t<_Tuple>>>::type, class = void>
+inline constexpr bool __can_make_from_tuple = false;
+
+template <class _Tp, class _Tuple, size_t... _Idx>
+inline constexpr bool __can_make_from_tuple<_Tp, _Tuple, __tuple_indices<_Idx...>,
+ enable_if_t<is_constructible_v<_Tp, decltype(std::get<_Idx>(std::declval<_Tuple>()))...>>> = true;
+
+// Based on LWG3528(https://wg21.link/LWG3528) and http://eel.is/c++draft/description#structure.requirements-9,
+// the standard allows to impose requirements, we constraint std::make_from_tuple to make std::make_from_tuple
+// SFINAE friendly and also avoid worse diagnostic messages. We still keep the constraints of std::__make_from_tuple_impl
+// so that std::__make_from_tuple_impl will have the same advantages when used alone.
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Tuple>
+ requires __can_make_from_tuple<_Tp, _Tuple> // strengthen
+#else
+template <class _Tp, class _Tuple, class = enable_if_t<__can_make_from_tuple<_Tp, _Tuple>>> // strengthen
+#endif // _LIBCPP_STD_VER >= 20
+inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp make_from_tuple(_Tuple&& __t)
+ _LIBCPP_NOEXCEPT_RETURN(std::__make_from_tuple_impl<_Tp>(
+ std::forward<_Tuple>(__t), typename __make_tuple_indices<tuple_size_v<remove_reference_t<_Tuple>>>::type{}))
+# undef _LIBCPP_NOEXCEPT_RETURN
+
+# endif // _LIBCPP_STD_VER >= 17
+
+#endif // !defined(_LIBCPP_CXX03_LANG)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+// clang-format on
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <exception>
+# include <iosfwd>
+# include <new>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_TUPLE
diff --git a/libcxx/include/__cxx03/type_traits b/libcxx/include/__cxx03/type_traits
new file mode 100644
index 00000000000000..7f231cd09df510
--- /dev/null
+++ b/libcxx/include/__cxx03/type_traits
@@ -0,0 +1,523 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_TYPE_TRAITS
+#define _LIBCPP_TYPE_TRAITS
+
+/*
+ type_traits synopsis
+
+namespace std
+{
+
+ // helper class:
+ template <class T, T v> struct integral_constant;
+ typedef integral_constant<bool, true> true_type; // C++11
+ typedef integral_constant<bool, false> false_type; // C++11
+
+ template <bool B> // C++14
+ using bool_constant = integral_constant<bool, B>; // C++14
+ typedef bool_constant<true> true_type; // C++14
+ typedef bool_constant<false> false_type; // C++14
+
+ // helper traits
+ template <bool, class T = void> struct enable_if;
+ template <bool, class T, class F> struct conditional;
+
+ // Primary classification traits:
+ template <class T> struct is_void;
+ template <class T> struct is_null_pointer; // C++14
+ template <class T> struct is_integral;
+ template <class T> struct is_floating_point;
+ template <class T> struct is_array;
+ template <class T> struct is_pointer;
+ template <class T> struct is_lvalue_reference;
+ template <class T> struct is_rvalue_reference;
+ template <class T> struct is_member_object_pointer;
+ template <class T> struct is_member_function_pointer;
+ template <class T> struct is_enum;
+ template <class T> struct is_union;
+ template <class T> struct is_class;
+ template <class T> struct is_function;
+
+ // Secondary classification traits:
+ template <class T> struct is_reference;
+ template <class T> struct is_arithmetic;
+ template <class T> struct is_fundamental;
+ template <class T> struct is_member_pointer;
+ template <class T> struct is_scoped_enum; // C++23
+ template <class T> struct is_scalar;
+ template <class T> struct is_object;
+ template <class T> struct is_compound;
+
+ // Const-volatile properties and transformations:
+ template <class T> struct is_const;
+ template <class T> struct is_volatile;
+ template <class T> struct remove_const;
+ template <class T> struct remove_volatile;
+ template <class T> struct remove_cv;
+ template <class T> struct add_const;
+ template <class T> struct add_volatile;
+ template <class T> struct add_cv;
+
+ // Reference transformations:
+ template <class T> struct remove_reference;
+ template <class T> struct add_lvalue_reference;
+ template <class T> struct add_rvalue_reference;
+
+ // Pointer transformations:
+ template <class T> struct remove_pointer;
+ template <class T> struct add_pointer;
+
+ template<class T> struct type_identity; // C++20
+ template<class T>
+ using type_identity_t = typename type_identity<T>::type; // C++20
+
+ // Integral properties:
+ template <class T> struct is_signed;
+ template <class T> struct is_unsigned;
+ template <class T> struct make_signed;
+ template <class T> struct make_unsigned;
+
+ // Array properties and transformations:
+ template <class T> struct rank;
+ template <class T, unsigned I = 0> struct extent;
+ template <class T> struct remove_extent;
+ template <class T> struct remove_all_extents;
+
+ template <class T> struct is_bounded_array; // C++20
+ template <class T> struct is_unbounded_array; // C++20
+
+ // Member introspection:
+ template <class T> struct is_pod;
+ template <class T> struct is_trivial;
+ template <class T> struct is_trivially_copyable;
+ template <class T> struct is_standard_layout;
+ template <class T> struct is_literal_type; // Deprecated in C++17; removed in C++20
+ template <class T> struct is_empty;
+ template <class T> struct is_polymorphic;
+ template <class T> struct is_abstract;
+ template <class T> struct is_final; // C++14
+ template <class T> struct is_aggregate; // C++17
+
+ template <class T, class... Args> struct is_constructible;
+ template <class T> struct is_default_constructible;
+ template <class T> struct is_copy_constructible;
+ template <class T> struct is_move_constructible;
+ template <class T, class U> struct is_assignable;
+ template <class T> struct is_copy_assignable;
+ template <class T> struct is_move_assignable;
+ template <class T, class U> struct is_swappable_with; // C++17
+ template <class T> struct is_swappable; // C++17
+ template <class T> struct is_destructible;
+
+ template <class T, class... Args> struct is_trivially_constructible;
+ template <class T> struct is_trivially_default_constructible;
+ template <class T> struct is_trivially_copy_constructible;
+ template <class T> struct is_trivially_move_constructible;
+ template <class T, class U> struct is_trivially_assignable;
+ template <class T> struct is_trivially_copy_assignable;
+ template <class T> struct is_trivially_move_assignable;
+ template <class T> struct is_trivially_destructible;
+
+ template <class T, class... Args> struct is_nothrow_constructible;
+ template <class T> struct is_nothrow_default_constructible;
+ template <class T> struct is_nothrow_copy_constructible;
+ template <class T> struct is_nothrow_move_constructible;
+ template <class T, class U> struct is_nothrow_assignable;
+ template <class T> struct is_nothrow_copy_assignable;
+ template <class T> struct is_nothrow_move_assignable;
+ template <class T, class U> struct is_nothrow_swappable_with; // C++17
+ template <class T> struct is_nothrow_swappable; // C++17
+ template <class T> struct is_nothrow_destructible;
+
+ template <class T> struct has_virtual_destructor;
+
+ template<class T> struct has_unique_object_representations; // C++17
+
+ // Relationships between types:
+ template <class T, class U> struct is_same;
+ template <class Base, class Derived> struct is_base_of;
+
+ template <class From, class To> struct is_convertible;
+ template <typename From, typename To> struct is_nothrow_convertible; // C++20
+ template <typename From, typename To> inline constexpr bool is_nothrow_convertible_v; // C++20
+
+ template <class Fn, class... ArgTypes> struct is_invocable;
+ template <class R, class Fn, class... ArgTypes> struct is_invocable_r;
+
+ template <class Fn, class... ArgTypes> struct is_nothrow_invocable;
+ template <class R, class Fn, class... ArgTypes> struct is_nothrow_invocable_r;
+
+ // Alignment properties and transformations:
+ template <class T> struct alignment_of;
+ template <size_t Len, size_t Align = most_stringent_alignment_requirement>
+ struct aligned_storage; // deprecated in C++23
+ template <size_t Len, class... Types> struct aligned_union; // deprecated in C++23
+ template <class T> struct remove_cvref; // C++20
+
+ template <class T> struct decay;
+ template <class... T> struct common_type;
+ template <class T> struct underlying_type;
+ template <class> class result_of; // undefined; deprecated in C++17; removed in C++20
+ template <class Fn, class... ArgTypes> class result_of<Fn(ArgTypes...)>; // deprecated in C++17; removed in C++20
+ template <class Fn, class... ArgTypes> struct invoke_result; // C++17
+
+ // const-volatile modifications:
+ template <class T>
+ using remove_const_t = typename remove_const<T>::type; // C++14
+ template <class T>
+ using remove_volatile_t = typename remove_volatile<T>::type; // C++14
+ template <class T>
+ using remove_cv_t = typename remove_cv<T>::type; // C++14
+ template <class T>
+ using add_const_t = typename add_const<T>::type; // C++14
+ template <class T>
+ using add_volatile_t = typename add_volatile<T>::type; // C++14
+ template <class T>
+ using add_cv_t = typename add_cv<T>::type; // C++14
+
+ // reference modifications:
+ template <class T>
+ using remove_reference_t = typename remove_reference<T>::type; // C++14
+ template <class T>
+ using add_lvalue_reference_t = typename add_lvalue_reference<T>::type; // C++14
+ template <class T>
+ using add_rvalue_reference_t = typename add_rvalue_reference<T>::type; // C++14
+
+ // sign modifications:
+ template <class T>
+ using make_signed_t = typename make_signed<T>::type; // C++14
+ template <class T>
+ using make_unsigned_t = typename make_unsigned<T>::type; // C++14
+
+ // array modifications:
+ template <class T>
+ using remove_extent_t = typename remove_extent<T>::type; // C++14
+ template <class T>
+ using remove_all_extents_t = typename remove_all_extents<T>::type; // C++14
+
+ template <class T>
+ inline constexpr bool is_bounded_array_v
+ = is_bounded_array<T>::value; // C++20
+ inline constexpr bool is_unbounded_array_v
+ = is_unbounded_array<T>::value; // C++20
+
+ // pointer modifications:
+ template <class T>
+ using remove_pointer_t = typename remove_pointer<T>::type; // C++14
+ template <class T>
+ using add_pointer_t = typename add_pointer<T>::type; // C++14
+
+ // other transformations:
+ template <size_t Len, size_t Align=default-alignment>
+ using aligned_storage_t = typename aligned_storage<Len,Align>::type; // C++14
+ template <size_t Len, class... Types>
+ using aligned_union_t = typename aligned_union<Len,Types...>::type; // C++14
+ template <class T>
+ using remove_cvref_t = typename remove_cvref<T>::type; // C++20
+ template <class T>
+ using decay_t = typename decay<T>::type; // C++14
+ template <bool b, class T=void>
+ using enable_if_t = typename enable_if<b,T>::type; // C++14
+ template <bool b, class T, class F>
+ using conditional_t = typename conditional<b,T,F>::type; // C++14
+ template <class... T>
+ using common_type_t = typename common_type<T...>::type; // C++14
+ template <class T>
+ using underlying_type_t = typename underlying_type<T>::type; // C++14
+ template <class T>
+ using result_of_t = typename result_of<T>::type; // C++14; deprecated in C++17; removed in C++20
+ template <class Fn, class... ArgTypes>
+ using invoke_result_t = typename invoke_result<Fn, ArgTypes...>::type; // C++17
+
+ template <class...>
+ using void_t = void; // C++17
+
+ // See C++14 20.10.4.1, primary type categories
+ template <class T> inline constexpr bool is_void_v
+ = is_void<T>::value; // C++17
+ template <class T> inline constexpr bool is_null_pointer_v
+ = is_null_pointer<T>::value; // C++17
+ template <class T> inline constexpr bool is_integral_v
+ = is_integral<T>::value; // C++17
+ template <class T> inline constexpr bool is_floating_point_v
+ = is_floating_point<T>::value; // C++17
+ template <class T> inline constexpr bool is_array_v
+ = is_array<T>::value; // C++17
+ template <class T> inline constexpr bool is_pointer_v
+ = is_pointer<T>::value; // C++17
+ template <class T> inline constexpr bool is_lvalue_reference_v
+ = is_lvalue_reference<T>::value; // C++17
+ template <class T> inline constexpr bool is_rvalue_reference_v
+ = is_rvalue_reference<T>::value; // C++17
+ template <class T> inline constexpr bool is_member_object_pointer_v
+ = is_member_object_pointer<T>::value; // C++17
+ template <class T> inline constexpr bool is_member_function_pointer_v
+ = is_member_function_pointer<T>::value; // C++17
+ template <class T> inline constexpr bool is_enum_v
+ = is_enum<T>::value; // C++17
+ template <class T> inline constexpr bool is_union_v
+ = is_union<T>::value; // C++17
+ template <class T> inline constexpr bool is_class_v
+ = is_class<T>::value; // C++17
+ template <class T> inline constexpr bool is_function_v
+ = is_function<T>::value; // C++17
+
+ // See C++14 20.10.4.2, composite type categories
+ template <class T> inline constexpr bool is_reference_v
+ = is_reference<T>::value; // C++17
+ template <class T> inline constexpr bool is_arithmetic_v
+ = is_arithmetic<T>::value; // C++17
+ template <class T> inline constexpr bool is_fundamental_v
+ = is_fundamental<T>::value; // C++17
+ template <class T> inline constexpr bool is_object_v
+ = is_object<T>::value; // C++17
+ template <class T> inline constexpr bool is_scalar_v
+ = is_scalar<T>::value; // C++17
+ template <class T> inline constexpr bool is_compound_v
+ = is_compound<T>::value; // C++17
+ template <class T> inline constexpr bool is_member_pointer_v
+ = is_member_pointer<T>::value; // C++17
+ template <class T> inline constexpr bool is_scoped_enum_v
+ = is_scoped_enum<T>::value; // C++23
+
+ // See C++14 20.10.4.3, type properties
+ template <class T> inline constexpr bool is_const_v
+ = is_const<T>::value; // C++17
+ template <class T> inline constexpr bool is_volatile_v
+ = is_volatile<T>::value; // C++17
+ template <class T> inline constexpr bool is_trivial_v
+ = is_trivial<T>::value; // C++17
+ template <class T> inline constexpr bool is_trivially_copyable_v
+ = is_trivially_copyable<T>::value; // C++17
+ template <class T> inline constexpr bool is_standard_layout_v
+ = is_standard_layout<T>::value; // C++17
+ template <class T> inline constexpr bool is_pod_v
+ = is_pod<T>::value; // C++17
+ template <class T> inline constexpr bool is_literal_type_v
+ = is_literal_type<T>::value; // C++17; deprecated in C++17; removed in C++20
+ template <class T> inline constexpr bool is_empty_v
+ = is_empty<T>::value; // C++17
+ template <class T> inline constexpr bool is_polymorphic_v
+ = is_polymorphic<T>::value; // C++17
+ template <class T> inline constexpr bool is_abstract_v
+ = is_abstract<T>::value; // C++17
+ template <class T> inline constexpr bool is_final_v
+ = is_final<T>::value; // C++17
+ template <class T> inline constexpr bool is_aggregate_v
+ = is_aggregate<T>::value; // C++17
+ template <class T> inline constexpr bool is_signed_v
+ = is_signed<T>::value; // C++17
+ template <class T> inline constexpr bool is_unsigned_v
+ = is_unsigned<T>::value; // C++17
+ template <class T, class... Args> inline constexpr bool is_constructible_v
+ = is_constructible<T, Args...>::value; // C++17
+ template <class T> inline constexpr bool is_default_constructible_v
+ = is_default_constructible<T>::value; // C++17
+ template <class T> inline constexpr bool is_copy_constructible_v
+ = is_copy_constructible<T>::value; // C++17
+ template <class T> inline constexpr bool is_move_constructible_v
+ = is_move_constructible<T>::value; // C++17
+ template <class T, class U> inline constexpr bool is_assignable_v
+ = is_assignable<T, U>::value; // C++17
+ template <class T> inline constexpr bool is_copy_assignable_v
+ = is_copy_assignable<T>::value; // C++17
+ template <class T> inline constexpr bool is_move_assignable_v
+ = is_move_assignable<T>::value; // C++17
+ template <class T, class U> inline constexpr bool is_swappable_with_v
+ = is_swappable_with<T, U>::value; // C++17
+ template <class T> inline constexpr bool is_swappable_v
+ = is_swappable<T>::value; // C++17
+ template <class T> inline constexpr bool is_destructible_v
+ = is_destructible<T>::value; // C++17
+ template <class T, class... Args> inline constexpr bool is_trivially_constructible_v
+ = is_trivially_constructible<T, Args...>::value; // C++17
+ template <class T> inline constexpr bool is_trivially_default_constructible_v
+ = is_trivially_default_constructible<T>::value; // C++17
+ template <class T> inline constexpr bool is_trivially_copy_constructible_v
+ = is_trivially_copy_constructible<T>::value; // C++17
+ template <class T> inline constexpr bool is_trivially_move_constructible_v
+ = is_trivially_move_constructible<T>::value; // C++17
+ template <class T, class U> inline constexpr bool is_trivially_assignable_v
+ = is_trivially_assignable<T, U>::value; // C++17
+ template <class T> inline constexpr bool is_trivially_copy_assignable_v
+ = is_trivially_copy_assignable<T>::value; // C++17
+ template <class T> inline constexpr bool is_trivially_move_assignable_v
+ = is_trivially_move_assignable<T>::value; // C++17
+ template <class T> inline constexpr bool is_trivially_destructible_v
+ = is_trivially_destructible<T>::value; // C++17
+ template <class T, class... Args> inline constexpr bool is_nothrow_constructible_v
+ = is_nothrow_constructible<T, Args...>::value; // C++17
+ template <class T> inline constexpr bool is_nothrow_default_constructible_v
+ = is_nothrow_default_constructible<T>::value; // C++17
+ template <class T> inline constexpr bool is_nothrow_copy_constructible_v
+ = is_nothrow_copy_constructible<T>::value; // C++17
+ template <class T> inline constexpr bool is_nothrow_move_constructible_v
+ = is_nothrow_move_constructible<T>::value; // C++17
+ template <class T, class U> inline constexpr bool is_nothrow_assignable_v
+ = is_nothrow_assignable<T, U>::value; // C++17
+ template <class T> inline constexpr bool is_nothrow_copy_assignable_v
+ = is_nothrow_copy_assignable<T>::value; // C++17
+ template <class T> inline constexpr bool is_nothrow_move_assignable_v
+ = is_nothrow_move_assignable<T>::value; // C++17
+ template <class T, class U> inline constexpr bool is_nothrow_swappable_with_v
+ = is_nothrow_swappable_with<T, U>::value; // C++17
+ template <class T> inline constexpr bool is_nothrow_swappable_v
+ = is_nothrow_swappable<T>::value; // C++17
+ template <class T> inline constexpr bool is_nothrow_destructible_v
+ = is_nothrow_destructible<T>::value; // C++17
+ template <class T> inline constexpr bool has_virtual_destructor_v
+ = has_virtual_destructor<T>::value; // C++17
+ template<class T> inline constexpr bool has_unique_object_representations_v // C++17
+ = has_unique_object_representations<T>::value;
+
+ // See C++14 20.10.5, type property queries
+ template <class T> inline constexpr size_t alignment_of_v
+ = alignment_of<T>::value; // C++17
+ template <class T> inline constexpr size_t rank_v
+ = rank<T>::value; // C++17
+ template <class T, unsigned I = 0> inline constexpr size_t extent_v
+ = extent<T, I>::value; // C++17
+
+ // See C++14 20.10.6, type relations
+ template <class T, class U> inline constexpr bool is_same_v
+ = is_same<T, U>::value; // C++17
+ template <class Base, class Derived> inline constexpr bool is_base_of_v
+ = is_base_of<Base, Derived>::value; // C++17
+ template <class From, class To> inline constexpr bool is_convertible_v
+ = is_convertible<From, To>::value; // C++17
+ template <class Fn, class... ArgTypes> inline constexpr bool is_invocable_v
+ = is_invocable<Fn, ArgTypes...>::value; // C++17
+ template <class R, class Fn, class... ArgTypes> inline constexpr bool is_invocable_r_v
+ = is_invocable_r<R, Fn, ArgTypes...>::value; // C++17
+ template <class Fn, class... ArgTypes> inline constexpr bool is_nothrow_invocable_v
+ = is_nothrow_invocable<Fn, ArgTypes...>::value; // C++17
+ template <class R, class Fn, class... ArgTypes> inline constexpr bool is_nothrow_invocable_r_v
+ = is_nothrow_invocable_r<R, Fn, ArgTypes...>::value; // C++17
+
+ // [meta.logical], logical operator traits:
+ template<class... B> struct conjunction; // C++17
+ template<class... B>
+ inline constexpr bool conjunction_v = conjunction<B...>::value; // C++17
+ template<class... B> struct disjunction; // C++17
+ template<class... B>
+ inline constexpr bool disjunction_v = disjunction<B...>::value; // C++17
+ template<class B> struct negation; // C++17
+ template<class B>
+ inline constexpr bool negation_v = negation<B>::value; // C++17
+
+}
+
+*/
+
+#include <__config>
+#include <__fwd/functional.h> // This is https://llvm.org/PR56938
+#include <__type_traits/add_const.h>
+#include <__type_traits/add_cv.h>
+#include <__type_traits/add_lvalue_reference.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/add_rvalue_reference.h>
+#include <__type_traits/add_volatile.h>
+#include <__type_traits/aligned_storage.h>
+#include <__type_traits/aligned_union.h>
+#include <__type_traits/alignment_of.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/extent.h>
+#include <__type_traits/has_virtual_destructor.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_abstract.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_assignable.h>
+#include <__type_traits/is_base_of.h>
+#include <__type_traits/is_class.h>
+#include <__type_traits/is_compound.h>
+#include <__type_traits/is_const.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/is_destructible.h>
+#include <__type_traits/is_empty.h>
+#include <__type_traits/is_enum.h>
+#include <__type_traits/is_floating_point.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_fundamental.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_literal_type.h>
+#include <__type_traits/is_member_pointer.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_nothrow_destructible.h>
+#include <__type_traits/is_object.h>
+#include <__type_traits/is_pod.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_polymorphic.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_scalar.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/is_standard_layout.h>
+#include <__type_traits/is_trivial.h>
+#include <__type_traits/is_trivially_assignable.h>
+#include <__type_traits/is_trivially_constructible.h>
+#include <__type_traits/is_trivially_copyable.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <__type_traits/is_union.h>
+#include <__type_traits/is_unsigned.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/is_volatile.h>
+#include <__type_traits/make_signed.h>
+#include <__type_traits/make_unsigned.h>
+#include <__type_traits/rank.h>
+#include <__type_traits/remove_all_extents.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_extent.h>
+#include <__type_traits/remove_pointer.h>
+#include <__type_traits/remove_reference.h>
+#include <__type_traits/remove_volatile.h>
+#include <__type_traits/result_of.h>
+#include <__type_traits/underlying_type.h>
+
+#if _LIBCPP_STD_VER >= 14
+# include <__type_traits/is_final.h>
+# include <__type_traits/is_null_pointer.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+# include <__type_traits/conjunction.h>
+# include <__type_traits/disjunction.h>
+# include <__type_traits/has_unique_object_representation.h>
+# include <__type_traits/invoke.h>
+# include <__type_traits/is_aggregate.h>
+# include <__type_traits/is_swappable.h>
+# include <__type_traits/negation.h>
+# include <__type_traits/void_t.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+# include <__type_traits/common_reference.h>
+# include <__type_traits/is_bounded_array.h>
+# include <__type_traits/is_constant_evaluated.h>
+# include <__type_traits/is_nothrow_convertible.h>
+# include <__type_traits/is_unbounded_array.h>
+# include <__type_traits/type_identity.h>
+# include <__type_traits/unwrap_ref.h>
+#endif
+
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#endif // _LIBCPP_TYPE_TRAITS
diff --git a/libcxx/include/__cxx03/typeindex b/libcxx/include/__cxx03/typeindex
new file mode 100644
index 00000000000000..6398aa40d616a7
--- /dev/null
+++ b/libcxx/include/__cxx03/typeindex
@@ -0,0 +1,106 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_TYPEINDEX
+#define _LIBCPP_TYPEINDEX
+
+/*
+
+ typeindex synopsis
+
+namespace std
+{
+
+class type_index
+{
+public:
+ type_index(const type_info& rhs) noexcept;
+
+ bool operator==(const type_index& rhs) const noexcept;
+ bool operator!=(const type_index& rhs) const noexcept; // removed in C++20
+ bool operator< (const type_index& rhs) const noexcept;
+ bool operator<=(const type_index& rhs) const noexcept;
+ bool operator> (const type_index& rhs) const noexcept;
+ bool operator>=(const type_index& rhs) const noexcept;
+ strong_ordering operator<=>(const type_index& rhs) const noexcept; // C++20
+
+ size_t hash_code() const noexcept;
+ const char* name() const noexcept;
+};
+
+template <>
+struct hash<type_index>
+ : public unary_function<type_index, size_t>
+{
+ size_t operator()(type_index index) const noexcept;
+};
+
+} // std
+
+*/
+
+#include <__config>
+#include <__functional/unary_function.h>
+#include <typeinfo>
+#include <version>
+
+// standard-mandated includes
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+class _LIBCPP_TEMPLATE_VIS type_index {
+ const type_info* __t_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI type_index(const type_info& __y) _NOEXCEPT : __t_(&__y) {}
+
+ _LIBCPP_HIDE_FROM_ABI bool operator==(const type_index& __y) const _NOEXCEPT { return *__t_ == *__y.__t_; }
+#if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(const type_index& __y) const _NOEXCEPT { return *__t_ != *__y.__t_; }
+#endif
+ _LIBCPP_HIDE_FROM_ABI bool operator<(const type_index& __y) const _NOEXCEPT { return __t_->before(*__y.__t_); }
+ _LIBCPP_HIDE_FROM_ABI bool operator<=(const type_index& __y) const _NOEXCEPT { return !__y.__t_->before(*__t_); }
+ _LIBCPP_HIDE_FROM_ABI bool operator>(const type_index& __y) const _NOEXCEPT { return __y.__t_->before(*__t_); }
+ _LIBCPP_HIDE_FROM_ABI bool operator>=(const type_index& __y) const _NOEXCEPT { return !__t_->before(*__y.__t_); }
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(const type_index& __y) const noexcept {
+ if (*__t_ == *__y.__t_)
+ return strong_ordering::equal;
+ if (__t_->before(*__y.__t_))
+ return strong_ordering::less;
+ return strong_ordering::greater;
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI size_t hash_code() const _NOEXCEPT { return __t_->hash_code(); }
+ _LIBCPP_HIDE_FROM_ABI const char* name() const _NOEXCEPT { return __t_->name(); }
+};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS hash;
+
+template <>
+struct _LIBCPP_TEMPLATE_VIS hash<type_index> : public __unary_function<type_index, size_t> {
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(type_index __index) const _NOEXCEPT { return __index.hash_code(); }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <iosfwd>
+# include <new>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_TYPEINDEX
diff --git a/libcxx/include/__cxx03/typeinfo b/libcxx/include/__cxx03/typeinfo
new file mode 100644
index 00000000000000..2727cad02fa99a
--- /dev/null
+++ b/libcxx/include/__cxx03/typeinfo
@@ -0,0 +1,389 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_TYPEINFO
+#define _LIBCPP_TYPEINFO
+
+/*
+
+ typeinfo synopsis
+
+namespace std {
+
+class type_info
+{
+public:
+ virtual ~type_info();
+
+ bool operator==(const type_info& rhs) const noexcept; // constexpr since C++23
+ bool operator!=(const type_info& rhs) const noexcept; // removed in C++20
+
+ bool before(const type_info& rhs) const noexcept;
+ size_t hash_code() const noexcept;
+ const char* name() const noexcept;
+
+ type_info(const type_info& rhs) = delete;
+ type_info& operator=(const type_info& rhs) = delete;
+};
+
+class bad_cast
+ : public exception
+{
+public:
+ bad_cast() noexcept;
+ bad_cast(const bad_cast&) noexcept;
+ bad_cast& operator=(const bad_cast&) noexcept;
+ virtual const char* what() const noexcept;
+};
+
+class bad_typeid
+ : public exception
+{
+public:
+ bad_typeid() noexcept;
+ bad_typeid(const bad_typeid&) noexcept;
+ bad_typeid& operator=(const bad_typeid&) noexcept;
+ virtual const char* what() const noexcept;
+};
+
+} // std
+
+*/
+
+#include <__config>
+#include <__exception/exception.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__verbose_abort>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if defined(_LIBCPP_ABI_VCRUNTIME)
+# include <vcruntime_typeinfo.h>
+#else
+
+namespace std // purposefully not using versioning namespace
+{
+
+# if defined(_LIBCPP_ABI_MICROSOFT)
+
+class _LIBCPP_EXPORTED_FROM_ABI type_info {
+ type_info& operator=(const type_info&);
+ type_info(const type_info&);
+
+ mutable struct {
+ const char* __undecorated_name;
+ const char __decorated_name[1];
+ } __data;
+
+ int __compare(const type_info& __rhs) const _NOEXCEPT;
+
+public:
+ virtual ~type_info();
+
+ const char* name() const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI bool before(const type_info& __arg) const _NOEXCEPT { return __compare(__arg) < 0; }
+
+ size_t hash_code() const _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator==(const type_info& __arg) const _NOEXCEPT {
+ // When evaluated in a constant expression, both type infos simply can't come
+ // from different translation units, so it is sufficient to compare their addresses.
+ if (__libcpp_is_constant_evaluated()) {
+ return this == &__arg;
+ }
+ return __compare(__arg) == 0;
+ }
+
+# if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(const type_info& __arg) const _NOEXCEPT { return !operator==(__arg); }
+# endif
+};
+
+# else // !defined(_LIBCPP_ABI_MICROSOFT)
+
+// ========================================================================== //
+// Implementations
+// ========================================================================== //
+// ------------------------------------------------------------------------- //
+// Unique
+// (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 1)
+// ------------------------------------------------------------------------- //
+// This implementation of type_info assumes a unique copy of the RTTI for a
+// given type inside a program. This is a valid assumption when abiding to the
+// Itanium ABI (http://itanium-cxx-abi.github.io/cxx-abi/abi.html#vtable-components).
+// Under this assumption, we can always compare the addresses of the type names
+// to implement equality-comparison of type_infos instead of having to perform
+// a deep string comparison.
+// -------------------------------------------------------------------------- //
+// NonUnique
+// (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 2)
+// -------------------------------------------------------------------------- //
+// This implementation of type_info does not assume there is always a unique
+// copy of the RTTI for a given type inside a program. For various reasons
+// the linker may have failed to merge every copy of a types RTTI
+// (For example: -Bsymbolic or llvm.org/PR37398). Under this assumption, two
+// type_infos are equal if their addresses are equal or if a deep string
+// comparison is equal.
+// -------------------------------------------------------------------------- //
+// NonUniqueARMRTTIBit
+// (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 3)
+// -------------------------------------------------------------------------- //
+// This implementation is specific to ARM64 on Apple platforms.
+//
+// This implementation of type_info does not assume always a unique copy of
+// the RTTI for a given type inside a program. When constructing the type_info,
+// the compiler packs the pointer to the type name into a uintptr_t and reserves
+// the high bit of that pointer, which is assumed to be free for use under that
+// ABI. If that high bit is set, that specific copy of the RTTI can't be assumed
+// to be unique within the program. If the high bit is unset, then the RTTI can
+// be assumed to be unique within the program.
+//
+// When comparing type_infos, if both RTTIs can be assumed to be unique, it
+// suffices to compare their addresses. If both the RTTIs can't be assumed to
+// be unique, we must perform a deep string comparison of the type names.
+// However, if one of the RTTIs is guaranteed unique and the other one isn't,
+// then both RTTIs are necessarily not to be considered equal.
+//
+// The intent of this design is to remove the need for weak symbols. Specifically,
+// if a type would normally have a default-visibility RTTI emitted as a weak
+// symbol, it is given hidden visibility instead and the non-unique bit is set.
+// Otherwise, types declared with hidden visibility are always considered to have
+// a unique RTTI: the RTTI is emitted with linkonce_odr linkage and is assumed
+// to be deduplicated by the linker within the linked image. Across linked image
+// boundaries, such types are thus considered different types.
+
+// This value can be overriden in the __config_site. When it's not overriden,
+// we pick a default implementation based on the platform here.
+# ifndef _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION
+
+// Windows and AIX binaries can't merge typeinfos, so use the NonUnique implementation.
+# if defined(_LIBCPP_OBJECT_FORMAT_COFF) || defined(_LIBCPP_OBJECT_FORMAT_XCOFF)
+# define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 2
+
+// On arm64 on Apple platforms, use the special NonUniqueARMRTTIBit implementation.
+# elif defined(__APPLE__) && defined(__LP64__) && !defined(__x86_64__)
+# define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 3
+
+// On all other platforms, assume the Itanium C++ ABI and use the Unique implementation.
+# else
+# define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 1
+# endif
+# endif
+
+struct __type_info_implementations {
+ struct __string_impl_base {
+ typedef const char* __type_name_t;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR static const char*
+ __type_name_to_string(__type_name_t __v) _NOEXCEPT {
+ return __v;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR static __type_name_t
+ __string_to_type_name(const char* __v) _NOEXCEPT {
+ return __v;
+ }
+ };
+
+ struct __unique_impl : __string_impl_base {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static size_t __hash(__type_name_t __v) _NOEXCEPT {
+ return reinterpret_cast<size_t>(__v);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static bool __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+ return __lhs == __rhs;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static bool __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+ return __lhs < __rhs;
+ }
+ };
+
+ struct __non_unique_impl : __string_impl_base {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static size_t __hash(__type_name_t __ptr) _NOEXCEPT {
+ size_t __hash = 5381;
+ while (unsigned char __c = static_cast<unsigned char>(*__ptr++))
+ __hash = (__hash * 33) ^ __c;
+ return __hash;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static bool __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+ return __lhs == __rhs || __builtin_strcmp(__lhs, __rhs) == 0;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static bool __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+ return __builtin_strcmp(__lhs, __rhs) < 0;
+ }
+ };
+
+ struct __non_unique_arm_rtti_bit_impl {
+ typedef uintptr_t __type_name_t;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static const char* __type_name_to_string(__type_name_t __v) _NOEXCEPT {
+ return reinterpret_cast<const char*>(__v & ~__non_unique_rtti_bit::value);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static __type_name_t __string_to_type_name(const char* __v) _NOEXCEPT {
+ return reinterpret_cast<__type_name_t>(__v);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static size_t __hash(__type_name_t __v) _NOEXCEPT {
+ if (__is_type_name_unique(__v))
+ return __v;
+ return __non_unique_impl::__hash(__type_name_to_string(__v));
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static bool __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+ if (__lhs == __rhs)
+ return true;
+ if (__is_type_name_unique(__lhs) || __is_type_name_unique(__rhs))
+ // Either both are unique and have a different address, or one of them
+ // is unique and the other one isn't. In both cases they are unequal.
+ return false;
+ return __builtin_strcmp(__type_name_to_string(__lhs), __type_name_to_string(__rhs)) == 0;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_ALWAYS_INLINE static bool __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+ if (__is_type_name_unique(__lhs) || __is_type_name_unique(__rhs))
+ return __lhs < __rhs;
+ return __builtin_strcmp(__type_name_to_string(__lhs), __type_name_to_string(__rhs)) < 0;
+ }
+
+ private:
+ // The unique bit is the top bit. It is expected that __type_name_t is 64 bits when
+ // this implementation is actually used.
+ typedef integral_constant<__type_name_t, (1ULL << ((__CHAR_BIT__ * sizeof(__type_name_t)) - 1))>
+ __non_unique_rtti_bit;
+
+ _LIBCPP_HIDE_FROM_ABI static bool __is_type_name_unique(__type_name_t __lhs) _NOEXCEPT {
+ return !(__lhs & __non_unique_rtti_bit::value);
+ }
+ };
+
+ typedef
+# if _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 1
+ __unique_impl
+# elif _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 2
+ __non_unique_impl
+# elif _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 3
+ __non_unique_arm_rtti_bit_impl
+# else
+# error invalid configuration for _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION
+# endif
+ __impl;
+};
+
+# if __has_cpp_attribute(_Clang::__ptrauth_vtable_pointer__)
+# if __has_feature(ptrauth_type_info_vtable_pointer_discrimination)
+# define _LIBCPP_TYPE_INFO_VTABLE_POINTER_AUTH \
+ [[_Clang::__ptrauth_vtable_pointer__(process_independent, address_discrimination, type_discrimination)]]
+# else
+# define _LIBCPP_TYPE_INFO_VTABLE_POINTER_AUTH \
+ [[_Clang::__ptrauth_vtable_pointer__( \
+ process_independent, no_address_discrimination, no_extra_discrimination)]]
+# endif
+# else
+# define _LIBCPP_TYPE_INFO_VTABLE_POINTER_AUTH
+# endif
+
+class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_TYPE_INFO_VTABLE_POINTER_AUTH type_info {
+ type_info& operator=(const type_info&);
+ type_info(const type_info&);
+
+protected:
+ typedef __type_info_implementations::__impl __impl;
+
+ __impl::__type_name_t __type_name;
+
+ _LIBCPP_HIDE_FROM_ABI explicit type_info(const char* __n) : __type_name(__impl::__string_to_type_name(__n)) {}
+
+public:
+ virtual ~type_info();
+
+ _LIBCPP_HIDE_FROM_ABI const char* name() const _NOEXCEPT { return __impl::__type_name_to_string(__type_name); }
+
+ _LIBCPP_HIDE_FROM_ABI bool before(const type_info& __arg) const _NOEXCEPT {
+ return __impl::__lt(__type_name, __arg.__type_name);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_t hash_code() const _NOEXCEPT { return __impl::__hash(__type_name); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator==(const type_info& __arg) const _NOEXCEPT {
+ // When evaluated in a constant expression, both type infos simply can't come
+ // from different translation units, so it is sufficient to compare their addresses.
+ if (__libcpp_is_constant_evaluated()) {
+ return this == &__arg;
+ }
+ return __impl::__eq(__type_name, __arg.__type_name);
+ }
+
+# if _LIBCPP_STD_VER <= 17
+ _LIBCPP_HIDE_FROM_ABI bool operator!=(const type_info& __arg) const _NOEXCEPT { return !operator==(__arg); }
+# endif
+};
+# endif // defined(_LIBCPP_ABI_MICROSOFT)
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_cast : public exception {
+public:
+ bad_cast() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI bad_cast(const bad_cast&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_cast& operator=(const bad_cast&) _NOEXCEPT = default;
+ ~bad_cast() _NOEXCEPT override;
+ const char* what() const _NOEXCEPT override;
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_typeid : public exception {
+public:
+ bad_typeid() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI bad_typeid(const bad_typeid&) _NOEXCEPT = default;
+ _LIBCPP_HIDE_FROM_ABI bad_typeid& operator=(const bad_typeid&) _NOEXCEPT = default;
+ ~bad_typeid() _NOEXCEPT override;
+ const char* what() const _NOEXCEPT override;
+};
+
+} // namespace std
+
+#endif // defined(_LIBCPP_ABI_VCRUNTIME)
+
+#if defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
+
+namespace std {
+
+class bad_cast : public exception {
+public:
+ bad_cast() _NOEXCEPT : exception("bad cast") {}
+
+private:
+ bad_cast(const char* const __message) _NOEXCEPT : exception(__message) {}
+};
+
+class bad_typeid : public exception {
+public:
+ bad_typeid() _NOEXCEPT : exception("bad typeid") {}
+
+private:
+ bad_typeid(const char* const __message) _NOEXCEPT : exception(__message) {}
+};
+
+} // namespace std
+
+#endif // defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_bad_cast() {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw bad_cast();
+#else
+ _LIBCPP_VERBOSE_ABORT("bad_cast was thrown in -fno-exceptions mode");
+#endif
+}
+_LIBCPP_END_NAMESPACE_STD
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdlib>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_TYPEINFO
diff --git a/libcxx/include/__cxx03/uchar.h b/libcxx/include/__cxx03/uchar.h
new file mode 100644
index 00000000000000..07b78611406d5f
--- /dev/null
+++ b/libcxx/include/__cxx03/uchar.h
@@ -0,0 +1,56 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_UCHAR_H
+#define _LIBCPP_UCHAR_H
+
+/*
+ uchar.h synopsis // since C++11
+
+Macros:
+
+ __STDC_UTF_16__
+ __STDC_UTF_32__
+
+Types:
+
+ mbstate_t
+ size_t
+
+size_t mbrtoc8(char8_t* pc8, const char* s, size_t n, mbstate_t* ps); // since C++20
+size_t c8rtomb(char* s, char8_t c8, mbstate_t* ps); // since C++20
+size_t mbrtoc16(char16_t* pc16, const char* s, size_t n, mbstate_t* ps);
+size_t c16rtomb(char* s, char16_t c16, mbstate_t* ps);
+size_t mbrtoc32(char32_t* pc32, const char* s, size_t n, mbstate_t* ps);
+size_t c32rtomb(char* s, char32_t c32, mbstate_t* ps);
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_CXX03_LANG)
+
+// Some platforms don't implement <uchar.h> and we don't want to give a hard
+// error on those platforms. When the platform doesn't provide <uchar.h>, at
+// least include <stddef.h> so we get the declaration for size_t, and try to
+// get the declaration of mbstate_t too.
+# if __has_include_next(<uchar.h>)
+# include_next <uchar.h>
+# else
+# include <__mbstate_t.h>
+# include <stddef.h>
+# endif
+
+#endif // _LIBCPP_CXX03_LANG
+
+#endif // _LIBCPP_UCHAR_H
diff --git a/libcxx/include/__cxx03/unordered_map b/libcxx/include/__cxx03/unordered_map
new file mode 100644
index 00000000000000..7c31c4fce26b03
--- /dev/null
+++ b/libcxx/include/__cxx03/unordered_map
@@ -0,0 +1,2541 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_UNORDERED_MAP
+#define _LIBCPP_UNORDERED_MAP
+
+/*
+
+ unordered_map synopsis
+
+#include <initializer_list>
+
+namespace std
+{
+
+template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
+ class Alloc = allocator<pair<const Key, T>>>
+class unordered_map
+{
+public:
+ // types
+ typedef Key key_type;
+ typedef T mapped_type;
+ typedef Hash hasher;
+ typedef Pred key_equal;
+ typedef Alloc allocator_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef /unspecified/ iterator;
+ typedef /unspecified/ const_iterator;
+ typedef /unspecified/ local_iterator;
+ typedef /unspecified/ const_local_iterator;
+
+ typedef unspecified node_type; // C++17
+ typedef INSERT_RETURN_TYPE<iterator, node_type> insert_return_type; // C++17
+
+ unordered_map()
+ noexcept(
+ is_nothrow_default_constructible<hasher>::value &&
+ is_nothrow_default_constructible<key_equal>::value &&
+ is_nothrow_default_constructible<allocator_type>::value);
+ explicit unordered_map(size_type n, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template <class InputIterator>
+ unordered_map(InputIterator f, InputIterator l,
+ size_type n = 0, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template<container-compatible-range<value_type> R>
+ unordered_map(from_range_t, R&& rg, size_type n = see below,
+ const hasher& hf = hasher(), const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type()); // C++23
+
+ explicit unordered_map(const allocator_type&);
+ unordered_map(const unordered_map&);
+ unordered_map(const unordered_map&, const Allocator&);
+ unordered_map(unordered_map&&)
+ noexcept(
+ is_nothrow_move_constructible<hasher>::value &&
+ is_nothrow_move_constructible<key_equal>::value &&
+ is_nothrow_move_constructible<allocator_type>::value);
+ unordered_map(unordered_map&&, const Allocator&);
+ unordered_map(initializer_list<value_type>, size_type n = 0,
+ const hasher& hf = hasher(), const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ unordered_map(size_type n, const allocator_type& a)
+ : unordered_map(n, hasher(), key_equal(), a) {} // C++14
+ unordered_map(size_type n, const hasher& hf, const allocator_type& a)
+ : unordered_map(n, hf, key_equal(), a) {} // C++14
+ template <class InputIterator>
+ unordered_map(InputIterator f, InputIterator l, size_type n, const allocator_type& a)
+ : unordered_map(f, l, n, hasher(), key_equal(), a) {} // C++14
+ template <class InputIterator>
+ unordered_map(InputIterator f, InputIterator l, size_type n, const hasher& hf,
+ const allocator_type& a)
+ : unordered_map(f, l, n, hf, key_equal(), a) {} // C++14
+ template<container-compatible-range<value_type> R>
+ unordered_map(from_range_t, R&& rg, size_type n, const allocator_type& a)
+ : unordered_map(from_range, std::forward<R>(rg), n, hasher(), key_equal(), a) { } // C++23
+ template<container-compatible-range<value_type> R>
+ unordered_map(from_range_t, R&& rg, size_type n, const hasher& hf, const allocator_type& a)
+ : unordered_map(from_range, std::forward<R>(rg), n, hf, key_equal(), a) { } // C++23
+ unordered_map(initializer_list<value_type> il, size_type n, const allocator_type& a)
+ : unordered_map(il, n, hasher(), key_equal(), a) {} // C++14
+ unordered_map(initializer_list<value_type> il, size_type n, const hasher& hf,
+ const allocator_type& a)
+ : unordered_map(il, n, hf, key_equal(), a) {} // C++14
+ ~unordered_map();
+ unordered_map& operator=(const unordered_map&);
+ unordered_map& operator=(unordered_map&&)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value &&
+ is_nothrow_move_assignable<hasher>::value &&
+ is_nothrow_move_assignable<key_equal>::value);
+ unordered_map& operator=(initializer_list<value_type>);
+
+ allocator_type get_allocator() const noexcept;
+
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ iterator begin() noexcept;
+ iterator end() noexcept;
+ const_iterator begin() const noexcept;
+ const_iterator end() const noexcept;
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+
+ template <class... Args>
+ pair<iterator, bool> emplace(Args&&... args);
+ template <class... Args>
+ iterator emplace_hint(const_iterator position, Args&&... args);
+ pair<iterator, bool> insert(const value_type& obj);
+ template <class P>
+ pair<iterator, bool> insert(P&& obj);
+ iterator insert(const_iterator hint, const value_type& obj);
+ template <class P>
+ iterator insert(const_iterator hint, P&& obj);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+ template<container-compatible-range<value_type> R>
+ void insert_range(R&& rg); // C++23
+ void insert(initializer_list<value_type>);
+
+ node_type extract(const_iterator position); // C++17
+ node_type extract(const key_type& x); // C++17
+ insert_return_type insert(node_type&& nh); // C++17
+ iterator insert(const_iterator hint, node_type&& nh); // C++17
+
+ template <class... Args>
+ pair<iterator, bool> try_emplace(const key_type& k, Args&&... args); // C++17
+ template <class... Args>
+ pair<iterator, bool> try_emplace(key_type&& k, Args&&... args); // C++17
+ template <class... Args>
+ iterator try_emplace(const_iterator hint, const key_type& k, Args&&... args); // C++17
+ template <class... Args>
+ iterator try_emplace(const_iterator hint, key_type&& k, Args&&... args); // C++17
+ template <class M>
+ pair<iterator, bool> insert_or_assign(const key_type& k, M&& obj); // C++17
+ template <class M>
+ pair<iterator, bool> insert_or_assign(key_type&& k, M&& obj); // C++17
+ template <class M>
+ iterator insert_or_assign(const_iterator hint, const key_type& k, M&& obj); // C++17
+ template <class M>
+ iterator insert_or_assign(const_iterator hint, key_type&& k, M&& obj); // C++17
+
+ iterator erase(const_iterator position);
+ iterator erase(iterator position); // C++14
+ size_type erase(const key_type& k);
+ iterator erase(const_iterator first, const_iterator last);
+ void clear() noexcept;
+
+ template<class H2, class P2>
+ void merge(unordered_map<Key, T, H2, P2, Allocator>& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_map<Key, T, H2, P2, Allocator>&& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_multimap<Key, T, H2, P2, Allocator>& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_multimap<Key, T, H2, P2, Allocator>&& source); // C++17
+
+ void swap(unordered_map&)
+ noexcept(
+ (!allocator_type::propagate_on_container_swap::value ||
+ __is_nothrow_swappable<allocator_type>::value) &&
+ __is_nothrow_swappable<hasher>::value &&
+ __is_nothrow_swappable<key_equal>::value);
+
+ hasher hash_function() const;
+ key_equal key_eq() const;
+
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ template<typename K>
+ iterator find(const K& x); // C++20
+ template<typename K>
+ const_iterator find(const K& x) const; // C++20
+ size_type count(const key_type& k) const;
+ template<typename K>
+ size_type count(const K& k) const; // C++20
+ bool contains(const key_type& k) const; // C++20
+ template<typename K>
+ bool contains(const K& k) const; // C++20
+ pair<iterator, iterator> equal_range(const key_type& k);
+ pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
+ template<typename K>
+ pair<iterator, iterator> equal_range(const K& k); // C++20
+ template<typename K>
+ pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
+
+ mapped_type& operator[](const key_type& k);
+ mapped_type& operator[](key_type&& k);
+
+ mapped_type& at(const key_type& k);
+ const mapped_type& at(const key_type& k) const;
+
+ size_type bucket_count() const noexcept;
+ size_type max_bucket_count() const noexcept;
+
+ size_type bucket_size(size_type n) const;
+ size_type bucket(const key_type& k) const;
+
+ local_iterator begin(size_type n);
+ local_iterator end(size_type n);
+ const_local_iterator begin(size_type n) const;
+ const_local_iterator end(size_type n) const;
+ const_local_iterator cbegin(size_type n) const;
+ const_local_iterator cend(size_type n) const;
+
+ float load_factor() const noexcept;
+ float max_load_factor() const noexcept;
+ void max_load_factor(float z);
+ void rehash(size_type n);
+ void reserve(size_type n);
+};
+
+template<class InputIterator,
+ class Hash = hash<iter_key_t<InputIterator>>, class Pred = equal_to<iter_key_t<InputIterator>>,
+ class Allocator = allocator<iter_to_alloc_t<InputIterator>>>
+unordered_map(InputIterator, InputIterator, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_map<iter_key_t<InputIterator>, iter_value_t<InputIterator>, Hash, Pred,
+ Allocator>; // C++17
+
+template<ranges::input_range R, class Hash = hash<range-key-type<R>>,
+ class Pred = equal_to<range-key-type<R>>,
+ class Allocator = allocator<range-to-alloc-type<R>>>
+ unordered_map(from_range_t, R&&, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_map<range-key-type<R>, range-mapped-type<R>, Hash, Pred, Allocator>; // C++23
+
+template<class Key, class T, class Hash = hash<Key>,
+ class Pred = equal_to<Key>, class Allocator = allocator<pair<const Key, T>>>
+unordered_map(initializer_list<pair<const Key, T>>, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_map<Key, T, Hash, Pred, Allocator>; // C++17
+
+template<class InputIterator, class Allocator>
+unordered_map(InputIterator, InputIterator, typename see below::size_type, Allocator)
+ -> unordered_map<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
+ hash<iter_key_t<InputIterator>>, equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
+
+template<class InputIterator, class Allocator>
+unordered_map(InputIterator, InputIterator, Allocator)
+ -> unordered_map<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
+ hash<iter_key_t<InputIterator>>, equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
+
+template<class InputIterator, class Hash, class Allocator>
+unordered_map(InputIterator, InputIterator, typename see below::size_type, Hash, Allocator)
+ -> unordered_map<iter_key_t<InputIterator>, iter_val_t<InputIterator>, Hash,
+ equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator>
+ unordered_map(from_range_t, R&&, typename see below::size_type, Allocator)
+ -> unordered_map<range-key-type<R>, range-mapped-type<R>, hash<range-key-type<R>>,
+ equal_to<range-key-type<R>>, Allocator>; // C++23
+
+template<ranges::input_range R, class Allocator>
+ unordered_map(from_range_t, R&&, Allocator)
+ -> unordered_map<range-key-type<R>, range-mapped-type<R>, hash<range-key-type<R>>,
+ equal_to<range-key-type<R>>, Allocator>; // C++23
+
+template<ranges::input_range R, class Hash, class Allocator>
+ unordered_map(from_range_t, R&&, typename see below::size_type, Hash, Allocator)
+ -> unordered_map<range-key-type<R>, range-mapped-type<R>, Hash,
+ equal_to<range-key-type<R>>, Allocator>; // C++23
+
+template<class Key, class T, typename Allocator>
+unordered_map(initializer_list<pair<const Key, T>>, typename see below::size_type, Allocator)
+ -> unordered_map<Key, T, hash<Key>, equal_to<Key>, Allocator>; // C++17
+
+template<class Key, class T, typename Allocator>
+unordered_map(initializer_list<pair<const Key, T>>, Allocator)
+ -> unordered_map<Key, T, hash<Key>, equal_to<Key>, Allocator>; // C++17
+
+template<class Key, class T, class Hash, class Allocator>
+unordered_map(initializer_list<pair<const Key, T>>, typename see below::size_type, Hash, Allocator)
+ -> unordered_map<Key, T, Hash, equal_to<Key>, Allocator>; // C++17
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ void swap(unordered_map<Key, T, Hash, Pred, Alloc>& x,
+ unordered_map<Key, T, Hash, Pred, Alloc>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ bool
+ operator==(const unordered_map<Key, T, Hash, Pred, Alloc>& x,
+ const unordered_map<Key, T, Hash, Pred, Alloc>& y);
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ bool
+ operator!=(const unordered_map<Key, T, Hash, Pred, Alloc>& x,
+ const unordered_map<Key, T, Hash, Pred, Alloc>& y); // Removed in C++20
+
+template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
+ class Alloc = allocator<pair<const Key, T>>>
+class unordered_multimap
+{
+public:
+ // types
+ typedef Key key_type;
+ typedef T mapped_type;
+ typedef Hash hasher;
+ typedef Pred key_equal;
+ typedef Alloc allocator_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef /unspecified/ iterator;
+ typedef /unspecified/ const_iterator;
+ typedef /unspecified/ local_iterator;
+ typedef /unspecified/ const_local_iterator;
+
+ typedef unspecified node_type; // C++17
+
+ unordered_multimap()
+ noexcept(
+ is_nothrow_default_constructible<hasher>::value &&
+ is_nothrow_default_constructible<key_equal>::value &&
+ is_nothrow_default_constructible<allocator_type>::value);
+ explicit unordered_multimap(size_type n, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template <class InputIterator>
+ unordered_multimap(InputIterator f, InputIterator l,
+ size_type n = 0, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template<container-compatible-range<value_type> R>
+ unordered_multimap(from_range_t, R&& rg, size_type n = see below,
+ const hasher& hf = hasher(), const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type()); // C++23
+ explicit unordered_multimap(const allocator_type&);
+ unordered_multimap(const unordered_multimap&);
+ unordered_multimap(const unordered_multimap&, const Allocator&);
+ unordered_multimap(unordered_multimap&&)
+ noexcept(
+ is_nothrow_move_constructible<hasher>::value &&
+ is_nothrow_move_constructible<key_equal>::value &&
+ is_nothrow_move_constructible<allocator_type>::value);
+ unordered_multimap(unordered_multimap&&, const Allocator&);
+ unordered_multimap(initializer_list<value_type>, size_type n = 0,
+ const hasher& hf = hasher(), const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ unordered_multimap(size_type n, const allocator_type& a)
+ : unordered_multimap(n, hasher(), key_equal(), a) {} // C++14
+ unordered_multimap(size_type n, const hasher& hf, const allocator_type& a)
+ : unordered_multimap(n, hf, key_equal(), a) {} // C++14
+ template <class InputIterator>
+ unordered_multimap(InputIterator f, InputIterator l, size_type n, const allocator_type& a)
+ : unordered_multimap(f, l, n, hasher(), key_equal(), a) {} // C++14
+ template <class InputIterator>
+ unordered_multimap(InputIterator f, InputIterator l, size_type n, const hasher& hf,
+ const allocator_type& a)
+ : unordered_multimap(f, l, n, hf, key_equal(), a) {} // C++14
+ template<container-compatible-range<value_type> R>
+ unordered_multimap(from_range_t, R&& rg, size_type n, const allocator_type& a)
+ : unordered_multimap(from_range, std::forward<R>(rg), n, hasher(), key_equal(), a) { } // C++23
+ template<container-compatible-range<value_type> R>
+ unordered_multimap(from_range_t, R&& rg, size_type n, const hasher& hf, const allocator_type& a)
+ : unordered_multimap(from_range, std::forward<R>(rg), n, hf, key_equal(), a) { } // C++23
+ unordered_multimap(initializer_list<value_type> il, size_type n, const allocator_type& a)
+ : unordered_multimap(il, n, hasher(), key_equal(), a) {} // C++14
+ unordered_multimap(initializer_list<value_type> il, size_type n, const hasher& hf,
+ const allocator_type& a)
+ : unordered_multimap(il, n, hf, key_equal(), a) {} // C++14
+ ~unordered_multimap();
+ unordered_multimap& operator=(const unordered_multimap&);
+ unordered_multimap& operator=(unordered_multimap&&)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value &&
+ is_nothrow_move_assignable<hasher>::value &&
+ is_nothrow_move_assignable<key_equal>::value);
+ unordered_multimap& operator=(initializer_list<value_type>);
+
+ allocator_type get_allocator() const noexcept;
+
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ iterator begin() noexcept;
+ iterator end() noexcept;
+ const_iterator begin() const noexcept;
+ const_iterator end() const noexcept;
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+
+ template <class... Args>
+ iterator emplace(Args&&... args);
+ template <class... Args>
+ iterator emplace_hint(const_iterator position, Args&&... args);
+ iterator insert(const value_type& obj);
+ template <class P>
+ iterator insert(P&& obj);
+ iterator insert(const_iterator hint, const value_type& obj);
+ template <class P>
+ iterator insert(const_iterator hint, P&& obj);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+ template<container-compatible-range<value_type> R>
+ void insert_range(R&& rg); // C++23
+ void insert(initializer_list<value_type>);
+
+ node_type extract(const_iterator position); // C++17
+ node_type extract(const key_type& x); // C++17
+ iterator insert(node_type&& nh); // C++17
+ iterator insert(const_iterator hint, node_type&& nh); // C++17
+
+ iterator erase(const_iterator position);
+ iterator erase(iterator position); // C++14
+ size_type erase(const key_type& k);
+ iterator erase(const_iterator first, const_iterator last);
+ void clear() noexcept;
+
+ template<class H2, class P2>
+ void merge(unordered_multimap<Key, T, H2, P2, Allocator>& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_multimap<Key, T, H2, P2, Allocator>&& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_map<Key, T, H2, P2, Allocator>& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_map<Key, T, H2, P2, Allocator>&& source); // C++17
+
+ void swap(unordered_multimap&)
+ noexcept(
+ (!allocator_type::propagate_on_container_swap::value ||
+ __is_nothrow_swappable<allocator_type>::value) &&
+ __is_nothrow_swappable<hasher>::value &&
+ __is_nothrow_swappable<key_equal>::value);
+
+ hasher hash_function() const;
+ key_equal key_eq() const;
+
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ template<typename K>
+ iterator find(const K& x); // C++20
+ template<typename K>
+ const_iterator find(const K& x) const; // C++20
+ size_type count(const key_type& k) const;
+ template<typename K>
+ size_type count(const K& k) const; // C++20
+ bool contains(const key_type& k) const; // C++20
+ template<typename K>
+ bool contains(const K& k) const; // C++20
+ pair<iterator, iterator> equal_range(const key_type& k);
+ pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
+ template<typename K>
+ pair<iterator, iterator> equal_range(const K& k); // C++20
+ template<typename K>
+ pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
+
+ size_type bucket_count() const noexcept;
+ size_type max_bucket_count() const noexcept;
+
+ size_type bucket_size(size_type n) const;
+ size_type bucket(const key_type& k) const;
+
+ local_iterator begin(size_type n);
+ local_iterator end(size_type n);
+ const_local_iterator begin(size_type n) const;
+ const_local_iterator end(size_type n) const;
+ const_local_iterator cbegin(size_type n) const;
+ const_local_iterator cend(size_type n) const;
+
+ float load_factor() const noexcept;
+ float max_load_factor() const noexcept;
+ void max_load_factor(float z);
+ void rehash(size_type n);
+ void reserve(size_type n);
+};
+
+template<class InputIterator,
+ class Hash = hash<iter_key_t<InputIterator>>, class Pred = equal_to<iter_key_t<InputIterator>>,
+ class Allocator = allocator<iter_to_alloc_t<InputIterator>>>
+unordered_multimap(InputIterator, InputIterator, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_multimap<iter_key_t<InputIterator>, iter_value_t<InputIterator>, Hash, Pred,
+ Allocator>; // C++17
+
+template<ranges::input_range R, class Hash = hash<range-key-type<R>>,
+ class Pred = equal_to<range-key-type<R>>,
+ class Allocator = allocator<range-to-alloc-type<R>>>
+ unordered_multimap(from_range_t, R&&, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_multimap<range-key-type<R>, range-mapped-type<R>, Hash, Pred, Allocator>; // C++23
+
+template<class Key, class T, class Hash = hash<Key>,
+ class Pred = equal_to<Key>, class Allocator = allocator<pair<const Key, T>>>
+unordered_multimap(initializer_list<pair<const Key, T>>, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_multimap<Key, T, Hash, Pred, Allocator>; // C++17
+
+template<class InputIterator, class Allocator>
+unordered_multimap(InputIterator, InputIterator, typename see below::size_type, Allocator)
+ -> unordered_multimap<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
+ hash<iter_key_t<InputIterator>>, equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
+
+template<class InputIterator, class Allocator>
+unordered_multimap(InputIterator, InputIterator, Allocator)
+ -> unordered_multimap<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
+ hash<iter_key_t<InputIterator>>, equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
+
+template<class InputIterator, class Hash, class Allocator>
+unordered_multimap(InputIterator, InputIterator, typename see below::size_type, Hash, Allocator)
+ -> unordered_multimap<iter_key_t<InputIterator>, iter_val_t<InputIterator>, Hash,
+ equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator>
+ unordered_multimap(from_range_t, R&&, typename see below::size_type, Allocator)
+ -> unordered_multimap<range-key-type<R>, range-mapped-type<R>, hash<range-key-type<R>>,
+ equal_to<range-key-type<R>>, Allocator>; // C++23
+
+template<ranges::input_range R, class Allocator>
+ unordered_multimap(from_range_t, R&&, Allocator)
+ -> unordered_multimap<range-key-type<R>, range-mapped-type<R>, hash<range-key-type<R>>,
+ equal_to<range-key-type<R>>, Allocator>; // C++23
+
+template<ranges::input_range R, class Hash, class Allocator>
+ unordered_multimap(from_range_t, R&&, typename see below::size_type, Hash, Allocator)
+ -> unordered_multimap<range-key-type<R>, range-mapped-type<R>, Hash,
+ equal_to<range-key-type<R>>, Allocator>; // C++23
+
+template<class Key, class T, typename Allocator>
+unordered_multimap(initializer_list<pair<const Key, T>>, typename see below::size_type, Allocator)
+ -> unordered_multimap<Key, T, hash<Key>, equal_to<Key>, Allocator>; // C++17
+
+template<class Key, class T, typename Allocator>
+unordered_multimap(initializer_list<pair<const Key, T>>, Allocator)
+ -> unordered_multimap<Key, T, hash<Key>, equal_to<Key>, Allocator>; // C++17
+
+template<class Key, class T, class Hash, class Allocator>
+unordered_multimap(initializer_list<pair<const Key, T>>, typename see below::size_type, Hash,
+ Allocator)
+ -> unordered_multimap<Key, T, Hash, equal_to<Key>, Allocator>; // C++17
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ void swap(unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
+ unordered_multimap<Key, T, Hash, Pred, Alloc>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class K, class T, class H, class P, class A, class Predicate>
+ typename unordered_map<K, T, H, P, A>::size_type
+ erase_if(unordered_map<K, T, H, P, A>& c, Predicate pred); // C++20
+
+template <class K, class T, class H, class P, class A, class Predicate>
+ typename unordered_multimap<K, T, H, P, A>::size_type
+ erase_if(unordered_multimap<K, T, H, P, A>& c, Predicate pred); // C++20
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ bool
+ operator==(const unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
+ const unordered_multimap<Key, T, Hash, Pred, Alloc>& y);
+
+template <class Key, class T, class Hash, class Pred, class Alloc>
+ bool
+ operator!=(const unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
+ const unordered_multimap<Key, T, Hash, Pred, Alloc>& y); // Removed in C++20
+
+} // std
+
+*/
+
+#include <__algorithm/is_permutation.h>
+#include <__assert>
+#include <__config>
+#include <__functional/is_transparent.h>
+#include <__functional/operations.h>
+#include <__hash_table>
+#include <__iterator/distance.h>
+#include <__iterator/erase_if_container.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/ranges_iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__node_handle>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__type_traits/is_allocator.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/forward.h>
+#include <stdexcept>
+#include <tuple>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [unord.map.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Key,
+ class _Cp,
+ class _Hash,
+ class _Pred,
+ bool = is_empty<_Hash>::value && !__libcpp_is_final<_Hash>::value>
+class __unordered_map_hasher : private _Hash {
+public:
+ _LIBCPP_HIDE_FROM_ABI __unordered_map_hasher() _NOEXCEPT_(is_nothrow_default_constructible<_Hash>::value) : _Hash() {}
+ _LIBCPP_HIDE_FROM_ABI __unordered_map_hasher(const _Hash& __h) _NOEXCEPT_(is_nothrow_copy_constructible<_Hash>::value)
+ : _Hash(__h) {}
+ _LIBCPP_HIDE_FROM_ABI const _Hash& hash_function() const _NOEXCEPT { return *this; }
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const _Cp& __x) const {
+ return static_cast<const _Hash&>(*this)(__x.__get_value().first);
+ }
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const _Key& __x) const { return static_cast<const _Hash&>(*this)(__x); }
+#if _LIBCPP_STD_VER >= 20
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const _K2& __x) const {
+ return static_cast<const _Hash&>(*this)(__x);
+ }
+#endif
+ _LIBCPP_HIDE_FROM_ABI void swap(__unordered_map_hasher& __y) _NOEXCEPT_(__is_nothrow_swappable_v<_Hash>) {
+ using std::swap;
+ swap(static_cast<_Hash&>(*this), static_cast<_Hash&>(__y));
+ }
+};
+
+template <class _Key, class _Cp, class _Hash, class _Pred>
+class __unordered_map_hasher<_Key, _Cp, _Hash, _Pred, false> {
+ _Hash __hash_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __unordered_map_hasher() _NOEXCEPT_(is_nothrow_default_constructible<_Hash>::value)
+ : __hash_() {}
+ _LIBCPP_HIDE_FROM_ABI __unordered_map_hasher(const _Hash& __h) _NOEXCEPT_(is_nothrow_copy_constructible<_Hash>::value)
+ : __hash_(__h) {}
+ _LIBCPP_HIDE_FROM_ABI const _Hash& hash_function() const _NOEXCEPT { return __hash_; }
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const _Cp& __x) const { return __hash_(__x.__get_value().first); }
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const _Key& __x) const { return __hash_(__x); }
+#if _LIBCPP_STD_VER >= 20
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI size_t operator()(const _K2& __x) const {
+ return __hash_(__x);
+ }
+#endif
+ _LIBCPP_HIDE_FROM_ABI void swap(__unordered_map_hasher& __y) _NOEXCEPT_(__is_nothrow_swappable_v<_Hash>) {
+ using std::swap;
+ swap(__hash_, __y.__hash_);
+ }
+};
+
+template <class _Key, class _Cp, class _Hash, class _Pred, bool __b>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(__unordered_map_hasher<_Key, _Cp, _Hash, _Pred, __b>& __x,
+ __unordered_map_hasher<_Key, _Cp, _Hash, _Pred, __b>& __y) _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+template <class _Key,
+ class _Cp,
+ class _Pred,
+ class _Hash,
+ bool = is_empty<_Pred>::value && !__libcpp_is_final<_Pred>::value>
+class __unordered_map_equal : private _Pred {
+public:
+ _LIBCPP_HIDE_FROM_ABI __unordered_map_equal() _NOEXCEPT_(is_nothrow_default_constructible<_Pred>::value) : _Pred() {}
+ _LIBCPP_HIDE_FROM_ABI __unordered_map_equal(const _Pred& __p) _NOEXCEPT_(is_nothrow_copy_constructible<_Pred>::value)
+ : _Pred(__p) {}
+ _LIBCPP_HIDE_FROM_ABI const _Pred& key_eq() const _NOEXCEPT { return *this; }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Cp& __x, const _Cp& __y) const {
+ return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y.__get_value().first);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Cp& __x, const _Key& __y) const {
+ return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Key& __x, const _Cp& __y) const {
+ return static_cast<const _Pred&>(*this)(__x, __y.__get_value().first);
+ }
+#if _LIBCPP_STD_VER >= 20
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Cp& __x, const _K2& __y) const {
+ return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y);
+ }
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _K2& __x, const _Cp& __y) const {
+ return static_cast<const _Pred&>(*this)(__x, __y.__get_value().first);
+ }
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Key& __x, const _K2& __y) const {
+ return static_cast<const _Pred&>(*this)(__x, __y);
+ }
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _K2& __x, const _Key& __y) const {
+ return static_cast<const _Pred&>(*this)(__x, __y);
+ }
+#endif
+ _LIBCPP_HIDE_FROM_ABI void swap(__unordered_map_equal& __y) _NOEXCEPT_(__is_nothrow_swappable_v<_Pred>) {
+ using std::swap;
+ swap(static_cast<_Pred&>(*this), static_cast<_Pred&>(__y));
+ }
+};
+
+template <class _Key, class _Cp, class _Pred, class _Hash>
+class __unordered_map_equal<_Key, _Cp, _Pred, _Hash, false> {
+ _Pred __pred_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __unordered_map_equal() _NOEXCEPT_(is_nothrow_default_constructible<_Pred>::value)
+ : __pred_() {}
+ _LIBCPP_HIDE_FROM_ABI __unordered_map_equal(const _Pred& __p) _NOEXCEPT_(is_nothrow_copy_constructible<_Pred>::value)
+ : __pred_(__p) {}
+ _LIBCPP_HIDE_FROM_ABI const _Pred& key_eq() const _NOEXCEPT { return __pred_; }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Cp& __x, const _Cp& __y) const {
+ return __pred_(__x.__get_value().first, __y.__get_value().first);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Cp& __x, const _Key& __y) const {
+ return __pred_(__x.__get_value().first, __y);
+ }
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Key& __x, const _Cp& __y) const {
+ return __pred_(__x, __y.__get_value().first);
+ }
+#if _LIBCPP_STD_VER >= 20
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Cp& __x, const _K2& __y) const {
+ return __pred_(__x.__get_value().first, __y);
+ }
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _K2& __x, const _Cp& __y) const {
+ return __pred_(__x, __y.__get_value().first);
+ }
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _Key& __x, const _K2& __y) const {
+ return __pred_(__x, __y);
+ }
+ template <typename _K2>
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const _K2& __x, const _Key& __y) const {
+ return __pred_(__x, __y);
+ }
+#endif
+ _LIBCPP_HIDE_FROM_ABI void swap(__unordered_map_equal& __y) _NOEXCEPT_(__is_nothrow_swappable_v<_Pred>) {
+ using std::swap;
+ swap(__pred_, __y.__pred_);
+ }
+};
+
+template <class _Key, class _Cp, class _Pred, class _Hash, bool __b>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(__unordered_map_equal<_Key, _Cp, _Pred, _Hash, __b>& __x, __unordered_map_equal<_Key, _Cp, _Pred, _Hash, __b>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+template <class _Alloc>
+class __hash_map_node_destructor {
+ typedef _Alloc allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+
+private:
+ allocator_type& __na_;
+
+public:
+ bool __first_constructed;
+ bool __second_constructed;
+
+ __hash_map_node_destructor& operator=(const __hash_map_node_destructor&) = delete;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __hash_map_node_destructor(allocator_type& __na) _NOEXCEPT
+ : __na_(__na),
+ __first_constructed(false),
+ __second_constructed(false) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __hash_map_node_destructor(__hash_node_destructor<allocator_type>&& __x) _NOEXCEPT
+ : __na_(__x.__na_),
+ __first_constructed(__x.__value_constructed),
+ __second_constructed(__x.__value_constructed) {
+ __x.__value_constructed = false;
+ }
+#else // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __hash_map_node_destructor(const __hash_node_destructor<allocator_type>& __x)
+ : __na_(__x.__na_), __first_constructed(__x.__value_constructed), __second_constructed(__x.__value_constructed) {
+ const_cast<bool&>(__x.__value_constructed) = false;
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI void operator()(pointer __p) _NOEXCEPT {
+ if (__second_constructed)
+ __alloc_traits::destroy(__na_, std::addressof(__p->__get_value().__get_value().second));
+ if (__first_constructed)
+ __alloc_traits::destroy(__na_, std::addressof(__p->__get_value().__get_value().first));
+ if (__p)
+ __alloc_traits::deallocate(__na_, __p, 1);
+ }
+};
+
+#ifndef _LIBCPP_CXX03_LANG
+template <class _Key, class _Tp>
+struct _LIBCPP_STANDALONE_DEBUG __hash_value_type {
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef pair<key_type&, mapped_type&> __nc_ref_pair_type;
+ typedef pair<key_type&&, mapped_type&&> __nc_rref_pair_type;
+
+private:
+ value_type __cc_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI value_type& __get_value() {
+# if _LIBCPP_STD_VER >= 17
+ return *std::launder(std::addressof(__cc_));
+# else
+ return __cc_;
+# endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const value_type& __get_value() const {
+# if _LIBCPP_STD_VER >= 17
+ return *std::launder(std::addressof(__cc_));
+# else
+ return __cc_;
+# endif
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __nc_ref_pair_type __ref() {
+ value_type& __v = __get_value();
+ return __nc_ref_pair_type(const_cast<key_type&>(__v.first), __v.second);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __nc_rref_pair_type __move() {
+ value_type& __v = __get_value();
+ return __nc_rref_pair_type(std::move(const_cast<key_type&>(__v.first)), std::move(__v.second));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_value_type& operator=(const __hash_value_type& __v) {
+ __ref() = __v.__get_value();
+ return *this;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_value_type& operator=(__hash_value_type&& __v) {
+ __ref() = __v.__move();
+ return *this;
+ }
+
+ template <class _ValueTp, __enable_if_t<__is_same_uncvref<_ValueTp, value_type>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI __hash_value_type& operator=(_ValueTp&& __v) {
+ __ref() = std::forward<_ValueTp>(__v);
+ return *this;
+ }
+
+ __hash_value_type(const __hash_value_type& __v) = delete;
+ __hash_value_type(__hash_value_type&& __v) = delete;
+ template <class... _Args>
+ explicit __hash_value_type(_Args&&... __args) = delete;
+
+ ~__hash_value_type() = delete;
+};
+
+#else
+
+template <class _Key, class _Tp>
+struct __hash_value_type {
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef pair<const key_type, mapped_type> value_type;
+
+private:
+ value_type __cc_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI value_type& __get_value() { return __cc_; }
+ _LIBCPP_HIDE_FROM_ABI const value_type& __get_value() const { return __cc_; }
+
+ ~__hash_value_type() = delete;
+};
+
+#endif
+
+template <class _HashIterator>
+class _LIBCPP_TEMPLATE_VIS __hash_map_iterator {
+ _HashIterator __i_;
+
+ typedef __hash_node_types_from_iterator<_HashIterator> _NodeTypes;
+
+public:
+ typedef forward_iterator_tag iterator_category;
+ typedef typename _NodeTypes::__map_value_type value_type;
+ typedef typename _NodeTypes::difference_type difference_type;
+ typedef value_type& reference;
+ typedef typename _NodeTypes::__map_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_iterator() _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_iterator(_HashIterator __i) _NOEXCEPT : __i_(__i) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __i_->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return pointer_traits<pointer>::pointer_to(__i_->__get_value()); }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_iterator& operator++() {
+ ++__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __hash_map_iterator operator++(int) {
+ __hash_map_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const __hash_map_iterator& __x, const __hash_map_iterator& __y) {
+ return __x.__i_ == __y.__i_;
+ }
+#if _LIBCPP_STD_VER <= 17
+ friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const __hash_map_iterator& __x, const __hash_map_iterator& __y) {
+ return __x.__i_ != __y.__i_;
+ }
+#endif
+
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
+};
+
+template <class _HashIterator>
+class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator {
+ _HashIterator __i_;
+
+ typedef __hash_node_types_from_iterator<_HashIterator> _NodeTypes;
+
+public:
+ typedef forward_iterator_tag iterator_category;
+ typedef typename _NodeTypes::__map_value_type value_type;
+ typedef typename _NodeTypes::difference_type difference_type;
+ typedef const value_type& reference;
+ typedef typename _NodeTypes::__const_map_value_type_pointer pointer;
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator() _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator(_HashIterator __i) _NOEXCEPT : __i_(__i) {}
+ _LIBCPP_HIDE_FROM_ABI
+ __hash_map_const_iterator(__hash_map_iterator<typename _HashIterator::__non_const_iterator> __i) _NOEXCEPT
+ : __i_(__i.__i_) {}
+
+ _LIBCPP_HIDE_FROM_ABI reference operator*() const { return __i_->__get_value(); }
+ _LIBCPP_HIDE_FROM_ABI pointer operator->() const { return pointer_traits<pointer>::pointer_to(__i_->__get_value()); }
+
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator& operator++() {
+ ++__i_;
+ return *this;
+ }
+ _LIBCPP_HIDE_FROM_ABI __hash_map_const_iterator operator++(int) {
+ __hash_map_const_iterator __t(*this);
+ ++(*this);
+ return __t;
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator==(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y) {
+ return __x.__i_ == __y.__i_;
+ }
+#if _LIBCPP_STD_VER <= 17
+ friend _LIBCPP_HIDE_FROM_ABI bool
+ operator!=(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y) {
+ return __x.__i_ != __y.__i_;
+ }
+#endif
+
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+ template <class, class, class, class, class>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
+};
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+class unordered_multimap;
+
+template <class _Key,
+ class _Tp,
+ class _Hash = hash<_Key>,
+ class _Pred = equal_to<_Key>,
+ class _Alloc = allocator<pair<const _Key, _Tp> > >
+class _LIBCPP_TEMPLATE_VIS unordered_map {
+public:
+ // types
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef __type_identity_t<_Hash> hasher;
+ typedef __type_identity_t<_Pred> key_equal;
+ typedef __type_identity_t<_Alloc> allocator_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ static_assert(is_same<value_type, typename allocator_type::value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+private:
+ typedef __hash_value_type<key_type, mapped_type> __value_type;
+ typedef __unordered_map_hasher<key_type, __value_type, hasher, key_equal> __hasher;
+ typedef __unordered_map_equal<key_type, __value_type, key_equal, hasher> __key_equal;
+ typedef __rebind_alloc<allocator_traits<allocator_type>, __value_type> __allocator_type;
+
+ typedef __hash_table<__value_type, __hasher, __key_equal, __allocator_type> __table;
+
+ __table __table_;
+
+ typedef typename __table::_NodeTypes _NodeTypes;
+ typedef typename __table::__node_pointer __node_pointer;
+ typedef typename __table::__node_const_pointer __node_const_pointer;
+ typedef typename __table::__node_traits __node_traits;
+ typedef typename __table::__node_allocator __node_allocator;
+ typedef typename __table::__node __node;
+ typedef __hash_map_node_destructor<__node_allocator> _Dp;
+ typedef unique_ptr<__node, _Dp> __node_holder;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+
+ static_assert(is_same<typename __table::__container_value_type, value_type>::value, "");
+ static_assert(is_same<typename __table::__node_value_type, __value_type>::value, "");
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+ typedef typename __table::size_type size_type;
+ typedef typename __table::difference_type difference_type;
+
+ typedef __hash_map_iterator<typename __table::iterator> iterator;
+ typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
+ typedef __hash_map_iterator<typename __table::local_iterator> local_iterator;
+ typedef __hash_map_const_iterator<typename __table::const_local_iterator> const_local_iterator;
+
+#if _LIBCPP_STD_VER >= 17
+ typedef __map_node_handle<__node, allocator_type> node_type;
+ typedef __insert_return_type<iterator, node_type> insert_return_type;
+#endif
+
+ template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+ template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
+
+ _LIBCPP_HIDE_FROM_ABI unordered_map() _NOEXCEPT_(is_nothrow_default_constructible<__table>::value) {}
+ explicit _LIBCPP_HIDE_FROM_ABI
+ unordered_map(size_type __n, const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_map(size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_map(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_map(_InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_map(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI unordered_map(
+ from_range_t,
+ _Range&& __range,
+ size_type __n = /*implementation-defined*/ 0,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal(),
+ const allocator_type& __a = allocator_type())
+ : __table_(__hf, __eql, typename __table::allocator_type(__a)) {
+ if (__n > 0) {
+ __table_.__rehash_unique(__n);
+ }
+ insert_range(std::forward<_Range>(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI explicit unordered_map(const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI unordered_map(const unordered_map& __u);
+ _LIBCPP_HIDE_FROM_ABI unordered_map(const unordered_map& __u, const allocator_type& __a);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI unordered_map(unordered_map&& __u) _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
+ _LIBCPP_HIDE_FROM_ABI unordered_map(unordered_map&& __u, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI unordered_map(initializer_list<value_type> __il);
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_map(initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI unordered_map(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+#endif // _LIBCPP_CXX03_LANG
+#if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI unordered_map(size_type __n, const allocator_type& __a)
+ : unordered_map(__n, hasher(), key_equal(), __a) {}
+ _LIBCPP_HIDE_FROM_ABI unordered_map(size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_map(__n, __hf, key_equal(), __a) {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_map(_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type& __a)
+ : unordered_map(__first, __last, __n, hasher(), key_equal(), __a) {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_map(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_map(__first, __last, __n, __hf, key_equal(), __a) {}
+
+# if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI unordered_map(from_range_t, _Range&& __range, size_type __n, const allocator_type& __a)
+ : unordered_map(from_range, std::forward<_Range>(__range), __n, hasher(), key_equal(), __a) {}
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_map(from_range_t, _Range&& __range, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_map(from_range, std::forward<_Range>(__range), __n, __hf, key_equal(), __a) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI unordered_map(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
+ : unordered_map(__il, __n, hasher(), key_equal(), __a) {}
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_map(initializer_list<value_type> __il, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_map(__il, __n, __hf, key_equal(), __a) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI ~unordered_map() {
+ static_assert(sizeof(std::__diagnose_unordered_container_requirements<_Key, _Hash, _Pred>(0)), "");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI unordered_map& operator=(const unordered_map& __u) {
+#ifndef _LIBCPP_CXX03_LANG
+ __table_ = __u.__table_;
+#else
+ if (this != std::addressof(__u)) {
+ __table_.clear();
+ __table_.hash_function() = __u.__table_.hash_function();
+ __table_.key_eq() = __u.__table_.key_eq();
+ __table_.max_load_factor() = __u.__table_.max_load_factor();
+ __table_.__copy_assign_alloc(__u.__table_);
+ insert(__u.begin(), __u.end());
+ }
+#endif
+ return *this;
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI unordered_map& operator=(unordered_map&& __u)
+ _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
+ _LIBCPP_HIDE_FROM_ABI unordered_map& operator=(initializer_list<value_type> __il);
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT {
+ return allocator_type(__table_.__node_alloc());
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __table_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __table_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __table_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return __table_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(const value_type& __x) { return __table_.__insert_unique(__x); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, const value_type& __x) { return insert(__x).first; }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ for (auto&& __element : __range) {
+ __table_.__insert_unique(std::forward<decltype(__element)>(__element));
+ }
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(value_type&& __x) {
+ return __table_.__insert_unique(std::move(__x));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, value_type&& __x) {
+ return __table_.__insert_unique(std::move(__x)).first;
+ }
+
+ template <class _Pp, __enable_if_t<is_constructible<value_type, _Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(_Pp&& __x) {
+ return __table_.__insert_unique(std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp, __enable_if_t<is_constructible<value_type, _Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, _Pp&& __x) {
+ return insert(std::forward<_Pp>(__x)).first;
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> emplace(_Args&&... __args) {
+ return __table_.__emplace_unique(std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator, _Args&&... __args) {
+ return __table_.__emplace_unique(std::forward<_Args>(__args)...).first;
+ }
+
+#endif // _LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 17
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> try_emplace(const key_type& __k, _Args&&... __args) {
+ return __table_.__emplace_unique_key_args(
+ __k, piecewise_construct, std::forward_as_tuple(__k), std::forward_as_tuple(std::forward<_Args>(__args)...));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> try_emplace(key_type&& __k, _Args&&... __args) {
+ return __table_.__emplace_unique_key_args(
+ __k,
+ piecewise_construct,
+ std::forward_as_tuple(std::move(__k)),
+ std::forward_as_tuple(std::forward<_Args>(__args)...));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator try_emplace(const_iterator, const key_type& __k, _Args&&... __args) {
+ return try_emplace(__k, std::forward<_Args>(__args)...).first;
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator try_emplace(const_iterator, key_type&& __k, _Args&&... __args) {
+ return try_emplace(std::move(__k), std::forward<_Args>(__args)...).first;
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert_or_assign(const key_type& __k, _Vp&& __v) {
+ pair<iterator, bool> __res = __table_.__emplace_unique_key_args(__k, __k, std::forward<_Vp>(__v));
+ if (!__res.second) {
+ __res.first->second = std::forward<_Vp>(__v);
+ }
+ return __res;
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert_or_assign(key_type&& __k, _Vp&& __v) {
+ pair<iterator, bool> __res = __table_.__emplace_unique_key_args(__k, std::move(__k), std::forward<_Vp>(__v));
+ if (!__res.second) {
+ __res.first->second = std::forward<_Vp>(__v);
+ }
+ return __res;
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_or_assign(const_iterator, const key_type& __k, _Vp&& __v) {
+ return insert_or_assign(__k, std::forward<_Vp>(__v)).first;
+ }
+
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI iterator insert_or_assign(const_iterator, key_type&& __k, _Vp&& __v) {
+ return insert_or_assign(std::move(__k), std::forward<_Vp>(__v)).first;
+ }
+#endif // _LIBCPP_STD_VER >= 17
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p) { return __table_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(iterator __p) { return __table_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __table_.__erase_unique(__k); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last) {
+ return __table_.erase(__first.__i_, __last.__i_);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __table_.clear(); }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI insert_return_type insert(node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to unordered_map::insert()");
+ return __table_.template __node_handle_insert_unique< node_type, insert_return_type>(std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to unordered_map::insert()");
+ return __table_.template __node_handle_insert_unique<node_type>(__hint.__i_, std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(key_type const& __key) {
+ return __table_.template __node_handle_extract<node_type>(__key);
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(const_iterator __it) {
+ return __table_.template __node_handle_extract<node_type>(__it.__i_);
+ }
+
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_unique(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_unique(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_unique(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_unique(__source.__table_);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void swap(unordered_map& __u) _NOEXCEPT_(__is_nothrow_swappable_v<__table>) {
+ __table_.swap(__u.__table_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI hasher hash_function() const { return __table_.hash_function().hash_function(); }
+ _LIBCPP_HIDE_FROM_ABI key_equal key_eq() const { return __table_.key_eq().key_eq(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __table_.find(__k); }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _K2& __k) {
+ return __table_.find(__k);
+ }
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _K2& __k) const {
+ return __table_.find(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __table_.__count_unique(__k); }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _K2& __k) const {
+ return __table_.__count_unique(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __k) const { return find(__k) != end(); }
+
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _K2& __k) const {
+ return find(__k) != end();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __table_.__equal_range_unique(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __table_.__equal_range_unique(__k);
+ }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _K2& __k) {
+ return __table_.__equal_range_unique(__k);
+ }
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _K2& __k) const {
+ return __table_.__equal_range_unique(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI mapped_type& operator[](const key_type& __k);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI mapped_type& operator[](key_type&& __k);
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI mapped_type& at(const key_type& __k);
+ _LIBCPP_HIDE_FROM_ABI const mapped_type& at(const key_type& __k) const;
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const _NOEXCEPT { return __table_.bucket_count(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const _NOEXCEPT { return __table_.max_bucket_count(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_size(size_type __n) const { return __table_.bucket_size(__n); }
+ _LIBCPP_HIDE_FROM_ABI size_type bucket(const key_type& __k) const { return __table_.bucket(__k); }
+
+ _LIBCPP_HIDE_FROM_ABI local_iterator begin(size_type __n) { return __table_.begin(__n); }
+ _LIBCPP_HIDE_FROM_ABI local_iterator end(size_type __n) { return __table_.end(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator begin(size_type __n) const { return __table_.cbegin(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator end(size_type __n) const { return __table_.cend(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cbegin(size_type __n) const { return __table_.cbegin(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cend(size_type __n) const { return __table_.cend(__n); }
+
+ _LIBCPP_HIDE_FROM_ABI float load_factor() const _NOEXCEPT { return __table_.load_factor(); }
+ _LIBCPP_HIDE_FROM_ABI float max_load_factor() const _NOEXCEPT { return __table_.max_load_factor(); }
+ _LIBCPP_HIDE_FROM_ABI void max_load_factor(float __mlf) { __table_.max_load_factor(__mlf); }
+ _LIBCPP_HIDE_FROM_ABI void rehash(size_type __n) { __table_.__rehash_unique(__n); }
+ _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n) { __table_.__reserve_unique(__n); }
+
+private:
+#ifdef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __node_holder __construct_node_with_key(const key_type& __k);
+#endif
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Hash = hash<__iter_key_type<_InputIterator>>,
+ class _Pred = equal_to<__iter_key_type<_InputIterator>>,
+ class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(_InputIterator,
+ _InputIterator,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator())
+ -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Hash, _Pred, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Hash = hash<__range_key_type<_Range>>,
+ class _Pred = equal_to<__range_key_type<_Range>>,
+ class _Allocator = allocator<__range_to_alloc_type<_Range>>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(from_range_t,
+ _Range&&,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator())
+ -> unordered_map<__range_key_type<_Range>, __range_mapped_type<_Range>, _Hash, _Pred, _Allocator>; // C++23
+# endif
+
+template <class _Key,
+ class _Tp,
+ class _Hash = hash<remove_const_t<_Key>>,
+ class _Pred = equal_to<remove_const_t<_Key>>,
+ class _Allocator = allocator<pair<const _Key, _Tp>>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(initializer_list<pair<_Key, _Tp>>,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator()) -> unordered_map<remove_const_t<_Key>, _Tp, _Hash, _Pred, _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_map<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ hash<__iter_key_type<_InputIterator>>,
+ equal_to<__iter_key_type<_InputIterator>>,
+ _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(_InputIterator, _InputIterator, _Allocator)
+ -> unordered_map<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ hash<__iter_key_type<_InputIterator>>,
+ equal_to<__iter_key_type<_InputIterator>>,
+ _Allocator>;
+
+template <class _InputIterator,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_map<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ _Hash,
+ equal_to<__iter_key_type<_InputIterator>>,
+ _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(from_range_t, _Range&&, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_map<__range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ hash<__range_key_type<_Range>>,
+ equal_to<__range_key_type<_Range>>,
+ _Allocator>;
+
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(from_range_t, _Range&&, _Allocator)
+ -> unordered_map<__range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ hash<__range_key_type<_Range>>,
+ equal_to<__range_key_type<_Range>>,
+ _Allocator>;
+
+template <ranges::input_range _Range,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(from_range_t, _Range&&, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_map<__range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ _Hash,
+ equal_to<__range_key_type<_Range>>,
+ _Allocator>;
+
+# endif
+
+template <class _Key, class _Tp, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_map<remove_const_t<_Key>, _Tp, hash<remove_const_t<_Key>>, equal_to<remove_const_t<_Key>>, _Allocator>;
+
+template <class _Key, class _Tp, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(initializer_list<pair<_Key, _Tp>>, _Allocator)
+ -> unordered_map<remove_const_t<_Key>, _Tp, hash<remove_const_t<_Key>>, equal_to<remove_const_t<_Key>>, _Allocator>;
+
+template <class _Key,
+ class _Tp,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_map(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_map<remove_const_t<_Key>, _Tp, _Hash, equal_to<remove_const_t<_Key>>, _Allocator>;
+#endif
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
+ size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __table_(__hf, __eql, typename __table::allocator_type(__a)) {
+ __table_.__rehash_unique(__n);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(const allocator_type& __a)
+ : __table_(typename __table::allocator_type(__a)) {}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(_InputIterator __first, _InputIterator __last) {
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, typename __table::allocator_type(__a)) {
+ __table_.__rehash_unique(__n);
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(const unordered_map& __u) : __table_(__u.__table_) {
+ __table_.__rehash_unique(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(const unordered_map& __u, const allocator_type& __a)
+ : __table_(__u.__table_, typename __table::allocator_type(__a)) {
+ __table_.__rehash_unique(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(unordered_map&& __u)
+ _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
+ : __table_(std::move(__u.__table_)) {}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(unordered_map&& __u, const allocator_type& __a)
+ : __table_(std::move(__u.__table_), typename __table::allocator_type(__a)) {
+ if (__a != __u.get_allocator()) {
+ iterator __i = __u.begin();
+ while (__u.size() != 0) {
+ __table_.__emplace_unique(__u.__table_.remove((__i++).__i_)->__get_value().__move());
+ }
+ }
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(initializer_list<value_type> __il) {
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
+ initializer_list<value_type> __il, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, typename __table::allocator_type(__a)) {
+ __table_.__rehash_unique(__n);
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>&
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(unordered_map&& __u)
+ _NOEXCEPT_(is_nothrow_move_assignable<__table>::value) {
+ __table_ = std::move(__u.__table_);
+ return *this;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>&
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(initializer_list<value_type> __il) {
+ __table_.__assign_unique(__il.begin(), __il.end());
+ return *this;
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+inline void unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first, _InputIterator __last) {
+ for (; __first != __last; ++__first)
+ __table_.__insert_unique(*__first);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_Tp& unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k) {
+ return __table_
+ .__emplace_unique_key_args(__k, piecewise_construct, std::forward_as_tuple(__k), std::forward_as_tuple())
+ .first->__get_value()
+ .second;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_Tp& unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](key_type&& __k) {
+ return __table_
+ .__emplace_unique_key_args(
+ __k, piecewise_construct, std::forward_as_tuple(std::move(__k)), std::forward_as_tuple())
+ .first->__get_value()
+ .second;
+}
+#else // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node_with_key(const key_type& __k) {
+ __node_allocator& __na = __table_.__node_alloc();
+ __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
+ __node_traits::construct(__na, std::addressof(__h->__get_value().__get_value().first), __k);
+ __h.get_deleter().__first_constructed = true;
+ __node_traits::construct(__na, std::addressof(__h->__get_value().__get_value().second));
+ __h.get_deleter().__second_constructed = true;
+ return __h;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_Tp& unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k) {
+ iterator __i = find(__k);
+ if (__i != end())
+ return __i->second;
+ __node_holder __h = __construct_node_with_key(__k);
+ pair<iterator, bool> __r = __table_.__node_insert_unique(__h.get());
+ __h.release();
+ return __r.first->second;
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_Tp& unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::at(const key_type& __k) {
+ iterator __i = find(__k);
+ if (__i == end())
+ __throw_out_of_range("unordered_map::at: key not found");
+ return __i->second;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+const _Tp& unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::at(const key_type& __k) const {
+ const_iterator __i = find(__k);
+ if (__i == end())
+ __throw_out_of_range("unordered_map::at: key not found");
+ return __i->second;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::size_type
+erase_if(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __c, _Predicate __pred) {
+ return std::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
+ const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ if (__x.size() != __y.size())
+ return false;
+ typedef typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator const_iterator;
+ for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end(); __i != __ex; ++__i) {
+ const_iterator __j = __y.find(__i->first);
+ if (__j == __ey || !(*__i == *__j))
+ return false;
+ }
+ return true;
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
+ const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+#endif
+
+template <class _Key,
+ class _Tp,
+ class _Hash = hash<_Key>,
+ class _Pred = equal_to<_Key>,
+ class _Alloc = allocator<pair<const _Key, _Tp> > >
+class _LIBCPP_TEMPLATE_VIS unordered_multimap {
+public:
+ // types
+ typedef _Key key_type;
+ typedef _Tp mapped_type;
+ typedef __type_identity_t<_Hash> hasher;
+ typedef __type_identity_t<_Pred> key_equal;
+ typedef __type_identity_t<_Alloc> allocator_type;
+ typedef pair<const key_type, mapped_type> value_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+ static_assert(is_same<value_type, typename allocator_type::value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+private:
+ typedef __hash_value_type<key_type, mapped_type> __value_type;
+ typedef __unordered_map_hasher<key_type, __value_type, hasher, key_equal> __hasher;
+ typedef __unordered_map_equal<key_type, __value_type, key_equal, hasher> __key_equal;
+ typedef __rebind_alloc<allocator_traits<allocator_type>, __value_type> __allocator_type;
+
+ typedef __hash_table<__value_type, __hasher, __key_equal, __allocator_type> __table;
+
+ __table __table_;
+
+ typedef typename __table::_NodeTypes _NodeTypes;
+ typedef typename __table::__node_traits __node_traits;
+ typedef typename __table::__node_allocator __node_allocator;
+ typedef typename __table::__node __node;
+ typedef __hash_map_node_destructor<__node_allocator> _Dp;
+ typedef unique_ptr<__node, _Dp> __node_holder;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+ static_assert(is_same<typename __node_traits::size_type, typename __alloc_traits::size_type>::value,
+ "Allocator uses different size_type for different types");
+
+public:
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+ typedef typename __table::size_type size_type;
+ typedef typename __table::difference_type difference_type;
+
+ typedef __hash_map_iterator<typename __table::iterator> iterator;
+ typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
+ typedef __hash_map_iterator<typename __table::local_iterator> local_iterator;
+ typedef __hash_map_const_iterator<typename __table::const_local_iterator> const_local_iterator;
+
+#if _LIBCPP_STD_VER >= 17
+ typedef __map_node_handle<__node, allocator_type> node_type;
+#endif
+
+ template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+ template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
+
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap() _NOEXCEPT_(is_nothrow_default_constructible<__table>::value) {}
+ explicit _LIBCPP_HIDE_FROM_ABI
+ unordered_multimap(size_type __n, const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_multimap(size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(
+ from_range_t,
+ _Range&& __range,
+ size_type __n = /*implementation-defined*/ 0,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal(),
+ const allocator_type& __a = allocator_type())
+ : __table_(__hf, __eql, typename __table::allocator_type(__a)) {
+ if (__n > 0) {
+ __table_.__rehash_multi(__n);
+ }
+ insert_range(std::forward<_Range>(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI explicit unordered_multimap(const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(const unordered_multimap& __u);
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(const unordered_multimap& __u, const allocator_type& __a);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(unordered_multimap&& __u)
+ _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(unordered_multimap&& __u, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(initializer_list<value_type> __il);
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+#endif // _LIBCPP_CXX03_LANG
+#if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(size_type __n, const allocator_type& __a)
+ : unordered_multimap(__n, hasher(), key_equal(), __a) {}
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_multimap(__n, __hf, key_equal(), __a) {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_multimap(_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type& __a)
+ : unordered_multimap(__first, __last, __n, hasher(), key_equal(), __a) {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_multimap(__first, __last, __n, __hf, key_equal(), __a) {}
+
+# if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(from_range_t, _Range&& __range, size_type __n, const allocator_type& __a)
+ : unordered_multimap(from_range, std::forward<_Range>(__range), __n, hasher(), key_equal(), __a) {}
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_multimap(from_range_t, _Range&& __range, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_multimap(from_range, std::forward<_Range>(__range), __n, __hf, key_equal(), __a) {}
+# endif
+
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
+ : unordered_multimap(__il, __n, hasher(), key_equal(), __a) {}
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_multimap(initializer_list<value_type> __il, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_multimap(__il, __n, __hf, key_equal(), __a) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI ~unordered_multimap() {
+ static_assert(sizeof(std::__diagnose_unordered_container_requirements<_Key, _Hash, _Pred>(0)), "");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap& operator=(const unordered_multimap& __u) {
+#ifndef _LIBCPP_CXX03_LANG
+ __table_ = __u.__table_;
+#else
+ if (this != std::addressof(__u)) {
+ __table_.clear();
+ __table_.hash_function() = __u.__table_.hash_function();
+ __table_.key_eq() = __u.__table_.key_eq();
+ __table_.max_load_factor() = __u.__table_.max_load_factor();
+ __table_.__copy_assign_alloc(__u.__table_);
+ insert(__u.begin(), __u.end());
+ }
+#endif
+ return *this;
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap& operator=(unordered_multimap&& __u)
+ _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
+ _LIBCPP_HIDE_FROM_ABI unordered_multimap& operator=(initializer_list<value_type> __il);
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT {
+ return allocator_type(__table_.__node_alloc());
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __table_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __table_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __table_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return __table_.end(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const value_type& __x) { return __table_.__insert_multi(__x); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __x) {
+ return __table_.__insert_multi(__p.__i_, __x);
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ for (auto&& __element : __range) {
+ __table_.__insert_multi(std::forward<decltype(__element)>(__element));
+ }
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(value_type&& __x) { return __table_.__insert_multi(std::move(__x)); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __x) {
+ return __table_.__insert_multi(__p.__i_, std::move(__x));
+ }
+
+ template <class _Pp, __enable_if_t<is_constructible<value_type, _Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(_Pp&& __x) {
+ return __table_.__insert_multi(std::forward<_Pp>(__x));
+ }
+
+ template <class _Pp, __enable_if_t<is_constructible<value_type, _Pp>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, _Pp&& __x) {
+ return __table_.__insert_multi(__p.__i_, std::forward<_Pp>(__x));
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace(_Args&&... __args) {
+ return __table_.__emplace_multi(std::forward<_Args>(__args)...);
+ }
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator __p, _Args&&... __args) {
+ return __table_.__emplace_hint_multi(__p.__i_, std::forward<_Args>(__args)...);
+ }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p) { return __table_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(iterator __p) { return __table_.erase(__p.__i_); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __table_.__erase_multi(__k); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last) {
+ return __table_.erase(__first.__i_, __last.__i_);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __table_.clear(); }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI iterator insert(node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to unordered_multimap::insert()");
+ return __table_.template __node_handle_insert_multi<node_type>(std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to unordered_multimap::insert()");
+ return __table_.template __node_handle_insert_multi<node_type>(__hint.__i_, std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(key_type const& __key) {
+ return __table_.template __node_handle_extract<node_type>(__key);
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(const_iterator __it) {
+ return __table_.template __node_handle_extract<node_type>(__it.__i_);
+ }
+
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_multi(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_multi(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_multi(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_multi(__source.__table_);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void swap(unordered_multimap& __u) _NOEXCEPT_(__is_nothrow_swappable_v<__table>) {
+ __table_.swap(__u.__table_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI hasher hash_function() const { return __table_.hash_function().hash_function(); }
+ _LIBCPP_HIDE_FROM_ABI key_equal key_eq() const { return __table_.key_eq().key_eq(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __table_.find(__k); }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _K2& __k) {
+ return __table_.find(__k);
+ }
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _K2& __k) const {
+ return __table_.find(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __table_.__count_multi(__k); }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _K2& __k) const {
+ return __table_.__count_multi(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __k) const { return find(__k) != end(); }
+
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _K2& __k) const {
+ return find(__k) != end();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __table_.__equal_range_multi(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __table_.__equal_range_multi(__k);
+ }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _K2& __k) {
+ return __table_.__equal_range_multi(__k);
+ }
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _K2& __k) const {
+ return __table_.__equal_range_multi(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const _NOEXCEPT { return __table_.bucket_count(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const _NOEXCEPT { return __table_.max_bucket_count(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_size(size_type __n) const { return __table_.bucket_size(__n); }
+ _LIBCPP_HIDE_FROM_ABI size_type bucket(const key_type& __k) const { return __table_.bucket(__k); }
+
+ _LIBCPP_HIDE_FROM_ABI local_iterator begin(size_type __n) { return __table_.begin(__n); }
+ _LIBCPP_HIDE_FROM_ABI local_iterator end(size_type __n) { return __table_.end(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator begin(size_type __n) const { return __table_.cbegin(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator end(size_type __n) const { return __table_.cend(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cbegin(size_type __n) const { return __table_.cbegin(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cend(size_type __n) const { return __table_.cend(__n); }
+
+ _LIBCPP_HIDE_FROM_ABI float load_factor() const _NOEXCEPT { return __table_.load_factor(); }
+ _LIBCPP_HIDE_FROM_ABI float max_load_factor() const _NOEXCEPT { return __table_.max_load_factor(); }
+ _LIBCPP_HIDE_FROM_ABI void max_load_factor(float __mlf) { __table_.max_load_factor(__mlf); }
+ _LIBCPP_HIDE_FROM_ABI void rehash(size_type __n) { __table_.__rehash_multi(__n); }
+ _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n) { __table_.__reserve_multi(__n); }
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Hash = hash<__iter_key_type<_InputIterator>>,
+ class _Pred = equal_to<__iter_key_type<_InputIterator>>,
+ class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(_InputIterator,
+ _InputIterator,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator())
+ -> unordered_multimap<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ _Hash,
+ _Pred,
+ _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Hash = hash<__range_key_type<_Range>>,
+ class _Pred = equal_to<__range_key_type<_Range>>,
+ class _Allocator = allocator<__range_to_alloc_type<_Range>>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(from_range_t,
+ _Range&&,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator())
+ -> unordered_multimap<__range_key_type<_Range>, __range_mapped_type<_Range>, _Hash, _Pred, _Allocator>;
+# endif
+
+template <class _Key,
+ class _Tp,
+ class _Hash = hash<remove_const_t<_Key>>,
+ class _Pred = equal_to<remove_const_t<_Key>>,
+ class _Allocator = allocator<pair<const _Key, _Tp>>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(
+ initializer_list<pair<_Key, _Tp>>,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator()) -> unordered_multimap<remove_const_t<_Key>, _Tp, _Hash, _Pred, _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_multimap<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ hash<__iter_key_type<_InputIterator>>,
+ equal_to<__iter_key_type<_InputIterator>>,
+ _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(_InputIterator, _InputIterator, _Allocator)
+ -> unordered_multimap<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ hash<__iter_key_type<_InputIterator>>,
+ equal_to<__iter_key_type<_InputIterator>>,
+ _Allocator>;
+
+template <class _InputIterator,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_multimap<__iter_key_type<_InputIterator>,
+ __iter_mapped_type<_InputIterator>,
+ _Hash,
+ equal_to<__iter_key_type<_InputIterator>>,
+ _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(from_range_t, _Range&&, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_multimap<__range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ hash<__range_key_type<_Range>>,
+ equal_to<__range_key_type<_Range>>,
+ _Allocator>;
+
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(from_range_t, _Range&&, _Allocator)
+ -> unordered_multimap<__range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ hash<__range_key_type<_Range>>,
+ equal_to<__range_key_type<_Range>>,
+ _Allocator>;
+
+template <ranges::input_range _Range,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(from_range_t, _Range&&, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_multimap<__range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ _Hash,
+ equal_to<__range_key_type<_Range>>,
+ _Allocator>;
+
+# endif
+
+template <class _Key, class _Tp, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_multimap<remove_const_t<_Key>,
+ _Tp,
+ hash<remove_const_t<_Key>>,
+ equal_to<remove_const_t<_Key>>,
+ _Allocator>;
+
+template <class _Key, class _Tp, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(initializer_list<pair<_Key, _Tp>>, _Allocator)
+ -> unordered_multimap<remove_const_t<_Key>,
+ _Tp,
+ hash<remove_const_t<_Key>>,
+ equal_to<remove_const_t<_Key>>,
+ _Allocator>;
+
+template <class _Key,
+ class _Tp,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multimap(
+ initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_multimap<remove_const_t<_Key>, _Tp, _Hash, equal_to<remove_const_t<_Key>>, _Allocator>;
+#endif
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
+ size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
+ size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __table_(__hf, __eql, typename __table::allocator_type(__a)) {
+ __table_.__rehash_multi(__n);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(_InputIterator __first, _InputIterator __last) {
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, typename __table::allocator_type(__a)) {
+ __table_.__rehash_multi(__n);
+ insert(__first, __last);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(const allocator_type& __a)
+ : __table_(typename __table::allocator_type(__a)) {}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(const unordered_multimap& __u)
+ : __table_(__u.__table_) {
+ __table_.__rehash_multi(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
+ const unordered_multimap& __u, const allocator_type& __a)
+ : __table_(__u.__table_, typename __table::allocator_type(__a)) {
+ __table_.__rehash_multi(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(unordered_multimap&& __u)
+ _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
+ : __table_(std::move(__u.__table_)) {}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
+ unordered_multimap&& __u, const allocator_type& __a)
+ : __table_(std::move(__u.__table_), typename __table::allocator_type(__a)) {
+ if (__a != __u.get_allocator()) {
+ iterator __i = __u.begin();
+ while (__u.size() != 0) {
+ __table_.__insert_multi(__u.__table_.remove((__i++).__i_)->__get_value().__move());
+ }
+ }
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(initializer_list<value_type> __il) {
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
+ initializer_list<value_type> __il, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, typename __table::allocator_type(__a)) {
+ __table_.__rehash_multi(__n);
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>&
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(unordered_multimap&& __u)
+ _NOEXCEPT_(is_nothrow_move_assignable<__table>::value) {
+ __table_ = std::move(__u.__table_);
+ return *this;
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>&
+unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(initializer_list<value_type> __il) {
+ __table_.__assign_multi(__il.begin(), __il.end());
+ return *this;
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+inline void unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first, _InputIterator __last) {
+ for (; __first != __last; ++__first)
+ __table_.__insert_multi(*__first);
+}
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::size_type
+erase_if(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __c, _Predicate __pred) {
+ return std::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
+ const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ if (__x.size() != __y.size())
+ return false;
+ typedef typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator const_iterator;
+ typedef pair<const_iterator, const_iterator> _EqRng;
+ for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;) {
+ _EqRng __xeq = __x.equal_range(__i->first);
+ _EqRng __yeq = __y.equal_range(__i->first);
+ if (std::distance(__xeq.first, __xeq.second) != std::distance(__yeq.first, __yeq.second) ||
+ !std::is_permutation(__xeq.first, __xeq.second, __yeq.first))
+ return false;
+ __i = __xeq.second;
+ }
+ return true;
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
+ const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _KeyT, class _ValueT, class _HashT = std::hash<_KeyT>, class _PredT = std::equal_to<_KeyT>>
+using unordered_map _LIBCPP_AVAILABILITY_PMR =
+ std::unordered_map<_KeyT, _ValueT, _HashT, _PredT, polymorphic_allocator<std::pair<const _KeyT, _ValueT>>>;
+
+template <class _KeyT, class _ValueT, class _HashT = std::hash<_KeyT>, class _PredT = std::equal_to<_KeyT>>
+using unordered_multimap _LIBCPP_AVAILABILITY_PMR =
+ std::unordered_multimap<_KeyT, _ValueT, _HashT, _PredT, polymorphic_allocator<std::pair<const _KeyT, _ValueT>>>;
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <bit>
+# include <concepts>
+# include <cstdlib>
+# include <iterator>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_UNORDERED_MAP
diff --git a/libcxx/include/__cxx03/unordered_set b/libcxx/include/__cxx03/unordered_set
new file mode 100644
index 00000000000000..3297294a893f82
--- /dev/null
+++ b/libcxx/include/__cxx03/unordered_set
@@ -0,0 +1,1811 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_UNORDERED_SET
+#define _LIBCPP_UNORDERED_SET
+
+// clang-format off
+
+/*
+
+ unordered_set synopsis
+
+#include <initializer_list>
+
+namespace std
+{
+
+template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
+ class Alloc = allocator<Value>>
+class unordered_set
+{
+public:
+ // types
+ typedef Value key_type;
+ typedef key_type value_type;
+ typedef Hash hasher;
+ typedef Pred key_equal;
+ typedef Alloc allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef /unspecified/ iterator;
+ typedef /unspecified/ const_iterator;
+ typedef /unspecified/ local_iterator;
+ typedef /unspecified/ const_local_iterator;
+
+ typedef unspecified node_type unspecified; // C++17
+ typedef INSERT_RETURN_TYPE<iterator, node_type> insert_return_type; // C++17
+
+ unordered_set()
+ noexcept(
+ is_nothrow_default_constructible<hasher>::value &&
+ is_nothrow_default_constructible<key_equal>::value &&
+ is_nothrow_default_constructible<allocator_type>::value);
+ explicit unordered_set(size_type n, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template <class InputIterator>
+ unordered_set(InputIterator f, InputIterator l,
+ size_type n = 0, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template<container-compatible-range<value_type> R>
+ unordered_set(from_range_t, R&& rg, size_type n = see below,
+ const hasher& hf = hasher(), const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type()); // C++23
+ explicit unordered_set(const allocator_type&);
+ unordered_set(const unordered_set&);
+ unordered_set(const unordered_set&, const Allocator&);
+ unordered_set(unordered_set&&)
+ noexcept(
+ is_nothrow_move_constructible<hasher>::value &&
+ is_nothrow_move_constructible<key_equal>::value &&
+ is_nothrow_move_constructible<allocator_type>::value);
+ unordered_set(unordered_set&&, const Allocator&);
+ unordered_set(initializer_list<value_type>, size_type n = 0,
+ const hasher& hf = hasher(), const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ unordered_set(size_type n, const allocator_type& a); // C++14
+ unordered_set(size_type n, const hasher& hf, const allocator_type& a); // C++14
+ template <class InputIterator>
+ unordered_set(InputIterator f, InputIterator l, size_type n, const allocator_type& a); // C++14
+ template <class InputIterator>
+ unordered_set(InputIterator f, InputIterator l, size_type n,
+ const hasher& hf, const allocator_type& a); // C++14
+ template<container-compatible-range<value_type> R>
+ unordered_set(from_range_t, R&& rg, size_type n, const allocator_type& a)
+ : unordered_set(from_range, std::forward<R>(rg), n, hasher(), key_equal(), a) { } // C++23
+ template<container-compatible-range<value_type> R>
+ unordered_set(from_range_t, R&& rg, size_type n, const hasher& hf, const allocator_type& a)
+ : unordered_set(from_range, std::forward<R>(rg), n, hf, key_equal(), a) { } // C++23
+ unordered_set(initializer_list<value_type> il, size_type n, const allocator_type& a); // C++14
+ unordered_set(initializer_list<value_type> il, size_type n,
+ const hasher& hf, const allocator_type& a); // C++14
+ ~unordered_set();
+ unordered_set& operator=(const unordered_set&);
+ unordered_set& operator=(unordered_set&&)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value &&
+ is_nothrow_move_assignable<hasher>::value &&
+ is_nothrow_move_assignable<key_equal>::value);
+ unordered_set& operator=(initializer_list<value_type>);
+
+ allocator_type get_allocator() const noexcept;
+
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ iterator begin() noexcept;
+ iterator end() noexcept;
+ const_iterator begin() const noexcept;
+ const_iterator end() const noexcept;
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+
+ template <class... Args>
+ pair<iterator, bool> emplace(Args&&... args);
+ template <class... Args>
+ iterator emplace_hint(const_iterator position, Args&&... args);
+ pair<iterator, bool> insert(const value_type& obj);
+ pair<iterator, bool> insert(value_type&& obj);
+ iterator insert(const_iterator hint, const value_type& obj);
+ iterator insert(const_iterator hint, value_type&& obj);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+ template<container-compatible-range<value_type> R>
+ void insert_range(R&& rg); // C++23
+ void insert(initializer_list<value_type>);
+
+ node_type extract(const_iterator position); // C++17
+ node_type extract(const key_type& x); // C++17
+ insert_return_type insert(node_type&& nh); // C++17
+ iterator insert(const_iterator hint, node_type&& nh); // C++17
+
+ iterator erase(const_iterator position);
+ iterator erase(iterator position); // C++14
+ size_type erase(const key_type& k);
+ iterator erase(const_iterator first, const_iterator last);
+ void clear() noexcept;
+
+ template<class H2, class P2>
+ void merge(unordered_set<Key, H2, P2, Allocator>& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_set<Key, H2, P2, Allocator>&& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_multiset<Key, H2, P2, Allocator>& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_multiset<Key, H2, P2, Allocator>&& source); // C++17
+
+ void swap(unordered_set&)
+ noexcept(allocator_traits<Allocator>::is_always_equal::value &&
+ noexcept(swap(declval<hasher&>(), declval<hasher&>())) &&
+ noexcept(swap(declval<key_equal&>(), declval<key_equal&>()))); // C++17
+
+ hasher hash_function() const;
+ key_equal key_eq() const;
+
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ template<typename K>
+ iterator find(const K& x); // C++20
+ template<typename K>
+ const_iterator find(const K& x) const; // C++20
+ size_type count(const key_type& k) const;
+ template<typename K>
+ size_type count(const K& k) const; // C++20
+ bool contains(const key_type& k) const; // C++20
+ template<typename K>
+ bool contains(const K& k) const; // C++20
+ pair<iterator, iterator> equal_range(const key_type& k);
+ pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
+ template<typename K>
+ pair<iterator, iterator> equal_range(const K& k); // C++20
+ template<typename K>
+ pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
+
+ size_type bucket_count() const noexcept;
+ size_type max_bucket_count() const noexcept;
+
+ size_type bucket_size(size_type n) const;
+ size_type bucket(const key_type& k) const;
+
+ local_iterator begin(size_type n);
+ local_iterator end(size_type n);
+ const_local_iterator begin(size_type n) const;
+ const_local_iterator end(size_type n) const;
+ const_local_iterator cbegin(size_type n) const;
+ const_local_iterator cend(size_type n) const;
+
+ float load_factor() const noexcept;
+ float max_load_factor() const noexcept;
+ void max_load_factor(float z);
+ void rehash(size_type n);
+ void reserve(size_type n);
+};
+
+template<class InputIterator,
+ class Hash = hash<typename iterator_traits<InputIterator>::value_type>,
+ class Pred = equal_to<typename iterator_traits<InputIterator>::value_type>,
+ class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+unordered_set(InputIterator, InputIterator, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_set<typename iterator_traits<InputIterator>::value_type,
+ Hash, Pred, Allocator>; // C++17
+
+template<ranges::input_range R,
+ class Hash = hash<ranges::range_value_t<R>>,
+ class Pred = equal_to<ranges::range_value_t<R>>,
+ class Allocator = allocator<ranges::range_value_t<R>>>
+ unordered_set(from_range_t, R&&, typename see below::size_type = see below, Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_set<ranges::range_value_t<R>, Hash, Pred, Allocator>; // C++23
+
+template<class T, class Hash = hash<T>,
+ class Pred = equal_to<T>, class Allocator = allocator<T>>
+unordered_set(initializer_list<T>, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_set<T, Hash, Pred, Allocator>; // C++17
+
+template<class InputIterator, class Allocator>
+unordered_set(InputIterator, InputIterator, typename see below::size_type, Allocator)
+ -> unordered_set<typename iterator_traits<InputIterator>::value_type,
+ hash<typename iterator_traits<InputIterator>::value_type>,
+ equal_to<typename iterator_traits<InputIterator>::value_type>,
+ Allocator>; // C++17
+
+template<class InputIterator, class Hash, class Allocator>
+unordered_set(InputIterator, InputIterator, typename see below::size_type,
+ Hash, Allocator)
+ -> unordered_set<typename iterator_traits<InputIterator>::value_type, Hash,
+ equal_to<typename iterator_traits<InputIterator>::value_type>,
+ Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator>
+ unordered_set(from_range_t, R&&, typename see below::size_type, Allocator)
+ -> unordered_set<ranges::range_value_t<R>, hash<ranges::range_value_t<R>>,
+ equal_to<ranges::range_value_t<R>>, Allocator>; // C++23
+
+template<ranges::input_range R, class Allocator>
+ unordered_set(from_range_t, R&&, Allocator)
+ -> unordered_set<ranges::range_value_t<R>, hash<ranges::range_value_t<R>>,
+ equal_to<ranges::range_value_t<R>>, Allocator>; // C++23
+
+template<ranges::input_range R, class Hash, class Allocator>
+ unordered_set(from_range_t, R&&, typename see below::size_type, Hash, Allocator)
+ -> unordered_set<ranges::range_value_t<R>, Hash,
+ equal_to<ranges::range_value_t<R>>, Allocator>; // C++23
+
+template<class T, class Allocator>
+unordered_set(initializer_list<T>, typename see below::size_type, Allocator)
+ -> unordered_set<T, hash<T>, equal_to<T>, Allocator>; // C++17
+
+template<class T, class Hash, class Allocator>
+unordered_set(initializer_list<T>, typename see below::size_type, Hash, Allocator)
+ -> unordered_set<T, Hash, equal_to<T>, Allocator>; // C++17
+
+template <class Value, class Hash, class Pred, class Alloc>
+ void swap(unordered_set<Value, Hash, Pred, Alloc>& x,
+ unordered_set<Value, Hash, Pred, Alloc>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class Value, class Hash, class Pred, class Alloc>
+ bool
+ operator==(const unordered_set<Value, Hash, Pred, Alloc>& x,
+ const unordered_set<Value, Hash, Pred, Alloc>& y);
+
+template <class Value, class Hash, class Pred, class Alloc>
+ bool
+ operator!=(const unordered_set<Value, Hash, Pred, Alloc>& x,
+ const unordered_set<Value, Hash, Pred, Alloc>& y); // removed in C++20
+
+template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
+ class Alloc = allocator<Value>>
+class unordered_multiset
+{
+public:
+ // types
+ typedef Value key_type;
+ typedef key_type value_type;
+ typedef Hash hasher;
+ typedef Pred key_equal;
+ typedef Alloc allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename allocator_traits<allocator_type>::pointer pointer;
+ typedef typename allocator_traits<allocator_type>::const_pointer const_pointer;
+ typedef typename allocator_traits<allocator_type>::size_type size_type;
+ typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+
+ typedef /unspecified/ iterator;
+ typedef /unspecified/ const_iterator;
+ typedef /unspecified/ local_iterator;
+ typedef /unspecified/ const_local_iterator;
+
+ typedef unspecified node_type unspecified; // C++17
+
+ unordered_multiset()
+ noexcept(
+ is_nothrow_default_constructible<hasher>::value &&
+ is_nothrow_default_constructible<key_equal>::value &&
+ is_nothrow_default_constructible<allocator_type>::value);
+ explicit unordered_multiset(size_type n, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template <class InputIterator>
+ unordered_multiset(InputIterator f, InputIterator l,
+ size_type n = 0, const hasher& hf = hasher(),
+ const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ template<container-compatible-range<value_type> R>
+ unordered_multiset(from_range_t, R&& rg, size_type n = see below,
+ const hasher& hf = hasher(), const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type()); // C++23
+ explicit unordered_multiset(const allocator_type&);
+ unordered_multiset(const unordered_multiset&);
+ unordered_multiset(const unordered_multiset&, const Allocator&);
+ unordered_multiset(unordered_multiset&&)
+ noexcept(
+ is_nothrow_move_constructible<hasher>::value &&
+ is_nothrow_move_constructible<key_equal>::value &&
+ is_nothrow_move_constructible<allocator_type>::value);
+ unordered_multiset(unordered_multiset&&, const Allocator&);
+ unordered_multiset(initializer_list<value_type>, size_type n = /see below/,
+ const hasher& hf = hasher(), const key_equal& eql = key_equal(),
+ const allocator_type& a = allocator_type());
+ unordered_multiset(size_type n, const allocator_type& a); // C++14
+ unordered_multiset(size_type n, const hasher& hf, const allocator_type& a); // C++14
+ template <class InputIterator>
+ unordered_multiset(InputIterator f, InputIterator l, size_type n, const allocator_type& a); // C++14
+ template <class InputIterator>
+ unordered_multiset(InputIterator f, InputIterator l, size_type n,
+ const hasher& hf, const allocator_type& a); // C++14
+ template<container-compatible-range<value_type> R>
+ unordered_multiset(from_range_t, R&& rg, size_type n, const allocator_type& a)
+ : unordered_multiset(from_range, std::forward<R>(rg), n, hasher(), key_equal(), a) { } // C++23
+ template<container-compatible-range<value_type> R>
+ unordered_multiset(from_range_t, R&& rg, size_type n, const hasher& hf, const allocator_type& a)
+ : unordered_multiset(from_range, std::forward<R>(rg), n, hf, key_equal(), a) { } // C++23
+ unordered_multiset(initializer_list<value_type> il, size_type n, const allocator_type& a); // C++14
+ unordered_multiset(initializer_list<value_type> il, size_type n,
+ const hasher& hf, const allocator_type& a); // C++14
+ ~unordered_multiset();
+ unordered_multiset& operator=(const unordered_multiset&);
+ unordered_multiset& operator=(unordered_multiset&&)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value &&
+ is_nothrow_move_assignable<allocator_type>::value &&
+ is_nothrow_move_assignable<hasher>::value &&
+ is_nothrow_move_assignable<key_equal>::value);
+ unordered_multiset& operator=(initializer_list<value_type>);
+
+ allocator_type get_allocator() const noexcept;
+
+ bool empty() const noexcept;
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+
+ iterator begin() noexcept;
+ iterator end() noexcept;
+ const_iterator begin() const noexcept;
+ const_iterator end() const noexcept;
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+
+ template <class... Args>
+ iterator emplace(Args&&... args);
+ template <class... Args>
+ iterator emplace_hint(const_iterator position, Args&&... args);
+ iterator insert(const value_type& obj);
+ iterator insert(value_type&& obj);
+ iterator insert(const_iterator hint, const value_type& obj);
+ iterator insert(const_iterator hint, value_type&& obj);
+ template <class InputIterator>
+ void insert(InputIterator first, InputIterator last);
+ template<container-compatible-range<value_type> R>
+ void insert_range(R&& rg); // C++23
+ void insert(initializer_list<value_type>);
+
+ node_type extract(const_iterator position); // C++17
+ node_type extract(const key_type& x); // C++17
+ iterator insert(node_type&& nh); // C++17
+ iterator insert(const_iterator hint, node_type&& nh); // C++17
+
+ iterator erase(const_iterator position);
+ iterator erase(iterator position); // C++14
+ size_type erase(const key_type& k);
+ iterator erase(const_iterator first, const_iterator last);
+ void clear() noexcept;
+
+ template<class H2, class P2>
+ void merge(unordered_multiset<Key, H2, P2, Allocator>& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_multiset<Key, H2, P2, Allocator>&& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_set<Key, H2, P2, Allocator>& source); // C++17
+ template<class H2, class P2>
+ void merge(unordered_set<Key, H2, P2, Allocator>&& source); // C++17
+
+ void swap(unordered_multiset&)
+ noexcept(allocator_traits<Allocator>::is_always_equal::value &&
+ noexcept(swap(declval<hasher&>(), declval<hasher&>())) &&
+ noexcept(swap(declval<key_equal&>(), declval<key_equal&>()))); // C++17
+
+ hasher hash_function() const;
+ key_equal key_eq() const;
+
+ iterator find(const key_type& k);
+ const_iterator find(const key_type& k) const;
+ template<typename K>
+ iterator find(const K& x); // C++20
+ template<typename K>
+ const_iterator find(const K& x) const; // C++20
+ size_type count(const key_type& k) const;
+ template<typename K>
+ size_type count(const K& k) const; // C++20
+ bool contains(const key_type& k) const; // C++20
+ template<typename K>
+ bool contains(const K& k) const; // C++20
+ pair<iterator, iterator> equal_range(const key_type& k);
+ pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
+ template<typename K>
+ pair<iterator, iterator> equal_range(const K& k); // C++20
+ template<typename K>
+ pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
+
+ size_type bucket_count() const noexcept;
+ size_type max_bucket_count() const noexcept;
+
+ size_type bucket_size(size_type n) const;
+ size_type bucket(const key_type& k) const;
+
+ local_iterator begin(size_type n);
+ local_iterator end(size_type n);
+ const_local_iterator begin(size_type n) const;
+ const_local_iterator end(size_type n) const;
+ const_local_iterator cbegin(size_type n) const;
+ const_local_iterator cend(size_type n) const;
+
+ float load_factor() const noexcept;
+ float max_load_factor() const noexcept;
+ void max_load_factor(float z);
+ void rehash(size_type n);
+ void reserve(size_type n);
+};
+
+template<class InputIterator,
+ class Hash = hash<typename iterator_traits<InputIterator>::value_type>,
+ class Pred = equal_to<typename iterator_traits<InputIterator>::value_type>,
+ class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+unordered_multiset(InputIterator, InputIterator, see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_multiset<typename iterator_traits<InputIterator>::value_type,
+ Hash, Pred, Allocator>; // C++17
+
+template<ranges::input_range R,
+ class Hash = hash<ranges::range_value_t<R>>,
+ class Pred = equal_to<ranges::range_value_t<R>>,
+ class Allocator = allocator<ranges::range_value_t<R>>>
+ unordered_multiset(from_range_t, R&&, typename see below::size_type = see below, Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_multiset<ranges::range_value_t<R>, Hash, Pred, Allocator>; // C++23
+
+template<class T, class Hash = hash<T>,
+ class Pred = equal_to<T>, class Allocator = allocator<T>>
+unordered_multiset(initializer_list<T>, typename see below::size_type = see below,
+ Hash = Hash(), Pred = Pred(), Allocator = Allocator())
+ -> unordered_multiset<T, Hash, Pred, Allocator>; // C++17
+
+template<class InputIterator, class Allocator>
+unordered_multiset(InputIterator, InputIterator, typename see below::size_type, Allocator)
+ -> unordered_multiset<typename iterator_traits<InputIterator>::value_type,
+ hash<typename iterator_traits<InputIterator>::value_type>,
+ equal_to<typename iterator_traits<InputIterator>::value_type>,
+ Allocator>; // C++17
+
+template<class InputIterator, class Hash, class Allocator>
+unordered_multiset(InputIterator, InputIterator, typename see below::size_type,
+ Hash, Allocator)
+ -> unordered_multiset<typename iterator_traits<InputIterator>::value_type, Hash,
+ equal_to<typename iterator_traits<InputIterator>::value_type>, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator>
+ unordered_multiset(from_range_t, R&&, typename see below::size_type, Allocator)
+ -> unordered_multiset<ranges::range_value_t<R>, hash<ranges::range_value_t<R>>,
+ equal_to<ranges::range_value_t<R>>, Allocator>; // C++23
+
+template<ranges::input_range R, class Allocator>
+ unordered_multiset(from_range_t, R&&, Allocator)
+ -> unordered_multiset<ranges::range_value_t<R>, hash<ranges::range_value_t<R>>,
+ equal_to<ranges::range_value_t<R>>, Allocator>; // C++23
+
+template<ranges::input_range R, class Hash, class Allocator>
+ unordered_multiset(from_range_t, R&&, typename see below::size_type, Hash, Allocator)
+ -> unordered_multiset<ranges::range_value_t<R>, Hash,
+ equal_to<ranges::range_value_t<R>>, Allocator>; // C++23
+
+template<class T, class Allocator>
+unordered_multiset(initializer_list<T>, typename see below::size_type, Allocator)
+ -> unordered_multiset<T, hash<T>, equal_to<T>, Allocator>; // C++17
+
+template<class T, class Hash, class Allocator>
+unordered_multiset(initializer_list<T>, typename see below::size_type, Hash, Allocator)
+ -> unordered_multiset<T, Hash, equal_to<T>, Allocator>; // C++17
+
+template <class Value, class Hash, class Pred, class Alloc>
+ void swap(unordered_multiset<Value, Hash, Pred, Alloc>& x,
+ unordered_multiset<Value, Hash, Pred, Alloc>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class K, class T, class H, class P, class A, class Predicate>
+ typename unordered_set<K, T, H, P, A>::size_type
+ erase_if(unordered_set<K, T, H, P, A>& c, Predicate pred); // C++20
+
+template <class K, class T, class H, class P, class A, class Predicate>
+ typename unordered_multiset<K, T, H, P, A>::size_type
+ erase_if(unordered_multiset<K, T, H, P, A>& c, Predicate pred); // C++20
+
+
+template <class Value, class Hash, class Pred, class Alloc>
+ bool
+ operator==(const unordered_multiset<Value, Hash, Pred, Alloc>& x,
+ const unordered_multiset<Value, Hash, Pred, Alloc>& y);
+
+template <class Value, class Hash, class Pred, class Alloc>
+ bool
+ operator!=(const unordered_multiset<Value, Hash, Pred, Alloc>& x,
+ const unordered_multiset<Value, Hash, Pred, Alloc>& y); // removed in C++20
+} // std
+
+*/
+
+// clang-format on
+
+#include <__algorithm/is_permutation.h>
+#include <__assert>
+#include <__config>
+#include <__functional/is_transparent.h>
+#include <__functional/operations.h>
+#include <__hash_table>
+#include <__iterator/distance.h>
+#include <__iterator/erase_if_container.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/ranges_iterator_traits.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__node_handle>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__type_traits/is_allocator.h>
+#include <__utility/forward.h>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [unord.set.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+class unordered_multiset;
+
+template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>, class _Alloc = allocator<_Value> >
+class _LIBCPP_TEMPLATE_VIS unordered_set {
+public:
+ // types
+ typedef _Value key_type;
+ typedef key_type value_type;
+ typedef __type_identity_t<_Hash> hasher;
+ typedef __type_identity_t<_Pred> key_equal;
+ typedef __type_identity_t<_Alloc> allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+ static_assert(is_same<value_type, typename allocator_type::value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+private:
+ typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
+
+ __table __table_;
+
+public:
+ typedef typename __table::pointer pointer;
+ typedef typename __table::const_pointer const_pointer;
+ typedef typename __table::size_type size_type;
+ typedef typename __table::difference_type difference_type;
+
+ typedef typename __table::const_iterator iterator;
+ typedef typename __table::const_iterator const_iterator;
+ typedef typename __table::const_local_iterator local_iterator;
+ typedef typename __table::const_local_iterator const_local_iterator;
+
+#if _LIBCPP_STD_VER >= 17
+ typedef __set_node_handle<typename __table::__node, allocator_type> node_type;
+ typedef __insert_return_type<iterator, node_type> insert_return_type;
+#endif
+
+ template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_set;
+ template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
+
+ _LIBCPP_HIDE_FROM_ABI unordered_set() _NOEXCEPT_(is_nothrow_default_constructible<__table>::value) {}
+ explicit _LIBCPP_HIDE_FROM_ABI
+ unordered_set(size_type __n, const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
+#if _LIBCPP_STD_VER >= 14
+ inline _LIBCPP_HIDE_FROM_ABI unordered_set(size_type __n, const allocator_type& __a)
+ : unordered_set(__n, hasher(), key_equal(), __a) {}
+ inline _LIBCPP_HIDE_FROM_ABI unordered_set(size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_set(__n, __hf, key_equal(), __a) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_set(size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_set(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_set(_InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_set(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI unordered_set(
+ from_range_t,
+ _Range&& __range,
+ size_type __n = /*implementation-defined*/ 0,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal(),
+ const allocator_type& __a = allocator_type())
+ : __table_(__hf, __eql, __a) {
+ if (__n > 0) {
+ __table_.__rehash_unique(__n);
+ }
+ insert_range(std::forward<_Range>(__range));
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+ template <class _InputIterator>
+ inline _LIBCPP_HIDE_FROM_ABI
+ unordered_set(_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type& __a)
+ : unordered_set(__first, __last, __n, hasher(), key_equal(), __a) {}
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_set(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_set(__first, __last, __n, __hf, key_equal(), __a) {}
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI unordered_set(from_range_t, _Range&& __range, size_type __n, const allocator_type& __a)
+ : unordered_set(from_range, std::forward<_Range>(__range), __n, hasher(), key_equal(), __a) {}
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_set(from_range_t, _Range&& __range, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_set(from_range, std::forward<_Range>(__range), __n, __hf, key_equal(), __a) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI explicit unordered_set(const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI unordered_set(const unordered_set& __u);
+ _LIBCPP_HIDE_FROM_ABI unordered_set(const unordered_set& __u, const allocator_type& __a);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI unordered_set(unordered_set&& __u) _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
+ _LIBCPP_HIDE_FROM_ABI unordered_set(unordered_set&& __u, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI unordered_set(initializer_list<value_type> __il);
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_set(initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI unordered_set(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+# if _LIBCPP_STD_VER >= 14
+ inline _LIBCPP_HIDE_FROM_ABI
+ unordered_set(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
+ : unordered_set(__il, __n, hasher(), key_equal(), __a) {}
+ inline _LIBCPP_HIDE_FROM_ABI
+ unordered_set(initializer_list<value_type> __il, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_set(__il, __n, __hf, key_equal(), __a) {}
+# endif
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI ~unordered_set() {
+ static_assert(sizeof(std::__diagnose_unordered_container_requirements<_Value, _Hash, _Pred>(0)), "");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI unordered_set& operator=(const unordered_set& __u) {
+ __table_ = __u.__table_;
+ return *this;
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI unordered_set& operator=(unordered_set&& __u)
+ _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
+ _LIBCPP_HIDE_FROM_ABI unordered_set& operator=(initializer_list<value_type> __il);
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT {
+ return allocator_type(__table_.__node_alloc());
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __table_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __table_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __table_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return __table_.end(); }
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> emplace(_Args&&... __args) {
+ return __table_.__emplace_unique(std::forward<_Args>(__args)...);
+ }
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator, _Args&&... __args) {
+ return __table_.__emplace_unique(std::forward<_Args>(__args)...).first;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(value_type&& __x) {
+ return __table_.__insert_unique(std::move(__x));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, value_type&& __x) { return insert(std::move(__x)).first; }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(const value_type& __x) { return __table_.__insert_unique(__x); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, const value_type& __x) { return insert(__x).first; }
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ for (auto&& __element : __range) {
+ __table_.__insert_unique(std::forward<decltype(__element)>(__element));
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p) { return __table_.erase(__p); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __table_.__erase_unique(__k); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last) {
+ return __table_.erase(__first, __last);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __table_.clear(); }
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI insert_return_type insert(node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to unordered_set::insert()");
+ return __table_.template __node_handle_insert_unique< node_type, insert_return_type>(std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __h, node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to unordered_set::insert()");
+ return __table_.template __node_handle_insert_unique<node_type>(__h, std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(key_type const& __key) {
+ return __table_.template __node_handle_extract<node_type>(__key);
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(const_iterator __it) {
+ return __table_.template __node_handle_extract<node_type>(__it);
+ }
+
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_set<key_type, _H2, _P2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __table_.__node_handle_merge_unique(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_set<key_type, _H2, _P2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __table_.__node_handle_merge_unique(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __table_.__node_handle_merge_unique(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ __table_.__node_handle_merge_unique(__source.__table_);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI void swap(unordered_set& __u) _NOEXCEPT_(__is_nothrow_swappable_v<__table>) {
+ __table_.swap(__u.__table_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI hasher hash_function() const { return __table_.hash_function(); }
+ _LIBCPP_HIDE_FROM_ABI key_equal key_eq() const { return __table_.key_eq(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __table_.find(__k); }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _K2& __k) {
+ return __table_.find(__k);
+ }
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _K2& __k) const {
+ return __table_.find(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __table_.__count_unique(__k); }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _K2& __k) const {
+ return __table_.__count_unique(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __k) const { return find(__k) != end(); }
+
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _K2& __k) const {
+ return find(__k) != end();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __table_.__equal_range_unique(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __table_.__equal_range_unique(__k);
+ }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _K2& __k) {
+ return __table_.__equal_range_unique(__k);
+ }
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _K2& __k) const {
+ return __table_.__equal_range_unique(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const _NOEXCEPT { return __table_.bucket_count(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const _NOEXCEPT { return __table_.max_bucket_count(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_size(size_type __n) const { return __table_.bucket_size(__n); }
+ _LIBCPP_HIDE_FROM_ABI size_type bucket(const key_type& __k) const { return __table_.bucket(__k); }
+
+ _LIBCPP_HIDE_FROM_ABI local_iterator begin(size_type __n) { return __table_.begin(__n); }
+ _LIBCPP_HIDE_FROM_ABI local_iterator end(size_type __n) { return __table_.end(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator begin(size_type __n) const { return __table_.cbegin(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator end(size_type __n) const { return __table_.cend(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cbegin(size_type __n) const { return __table_.cbegin(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cend(size_type __n) const { return __table_.cend(__n); }
+
+ _LIBCPP_HIDE_FROM_ABI float load_factor() const _NOEXCEPT { return __table_.load_factor(); }
+ _LIBCPP_HIDE_FROM_ABI float max_load_factor() const _NOEXCEPT { return __table_.max_load_factor(); }
+ _LIBCPP_HIDE_FROM_ABI void max_load_factor(float __mlf) { __table_.max_load_factor(__mlf); }
+ _LIBCPP_HIDE_FROM_ABI void rehash(size_type __n) { __table_.__rehash_unique(__n); }
+ _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n) { __table_.__reserve_unique(__n); }
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Hash = hash<__iter_value_type<_InputIterator>>,
+ class _Pred = equal_to<__iter_value_type<_InputIterator>>,
+ class _Allocator = allocator<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(_InputIterator,
+ _InputIterator,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator()) -> unordered_set<__iter_value_type<_InputIterator>, _Hash, _Pred, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Hash = hash<ranges::range_value_t<_Range>>,
+ class _Pred = equal_to<ranges::range_value_t<_Range>>,
+ class _Allocator = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(
+ from_range_t,
+ _Range&&,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator()) -> unordered_set<ranges::range_value_t<_Range>, _Hash, _Pred, _Allocator>; // C++23
+# endif
+
+template <class _Tp,
+ class _Hash = hash<_Tp>,
+ class _Pred = equal_to<_Tp>,
+ class _Allocator = allocator<_Tp>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(initializer_list<_Tp>,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator()) -> unordered_set<_Tp, _Hash, _Pred, _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_set<__iter_value_type<_InputIterator>,
+ hash<__iter_value_type<_InputIterator>>,
+ equal_to<__iter_value_type<_InputIterator>>,
+ _Allocator>;
+
+template <class _InputIterator,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_set<__iter_value_type<_InputIterator>, _Hash, equal_to<__iter_value_type<_InputIterator>>, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(from_range_t, _Range&&, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_set<ranges::range_value_t<_Range>,
+ hash<ranges::range_value_t<_Range>>,
+ equal_to<ranges::range_value_t<_Range>>,
+ _Allocator>;
+
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(from_range_t, _Range&&, _Allocator)
+ -> unordered_set<ranges::range_value_t<_Range>,
+ hash<ranges::range_value_t<_Range>>,
+ equal_to<ranges::range_value_t<_Range>>,
+ _Allocator>;
+
+template <ranges::input_range _Range,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(from_range_t, _Range&&, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_set<ranges::range_value_t<_Range>, _Hash, equal_to<ranges::range_value_t<_Range>>, _Allocator>;
+
+# endif
+
+template <class _Tp, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_set<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
+
+template <class _Tp,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_set<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
+#endif
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
+ size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_unique(__n);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(_InputIterator __first, _InputIterator __last) {
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_unique(__n);
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(const allocator_type& __a) : __table_(__a) {}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(const unordered_set& __u) : __table_(__u.__table_) {
+ __table_.__rehash_unique(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(const unordered_set& __u, const allocator_type& __a)
+ : __table_(__u.__table_, __a) {
+ __table_.__rehash_unique(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(unordered_set&& __u)
+ _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
+ : __table_(std::move(__u.__table_)) {}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(unordered_set&& __u, const allocator_type& __a)
+ : __table_(std::move(__u.__table_), __a) {
+ if (__a != __u.get_allocator()) {
+ iterator __i = __u.begin();
+ while (__u.size() != 0)
+ __table_.__insert_unique(std::move(__u.__table_.remove(__i++)->__get_value()));
+ }
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(initializer_list<value_type> __il) {
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
+ initializer_list<value_type> __il, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_unique(__n);
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_unique(__n);
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline unordered_set<_Value, _Hash, _Pred, _Alloc>&
+unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(unordered_set&& __u)
+ _NOEXCEPT_(is_nothrow_move_assignable<__table>::value) {
+ __table_ = std::move(__u.__table_);
+ return *this;
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline unordered_set<_Value, _Hash, _Pred, _Alloc>&
+unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(initializer_list<value_type> __il) {
+ __table_.__assign_unique(__il.begin(), __il.end());
+ return *this;
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+inline void unordered_set<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first, _InputIterator __last) {
+ for (; __first != __last; ++__first)
+ __table_.__insert_unique(*__first);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(unordered_set<_Value, _Hash, _Pred, _Alloc>& __x, unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Value, class _Hash, class _Pred, class _Alloc, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename unordered_set<_Value, _Hash, _Pred, _Alloc>::size_type
+erase_if(unordered_set<_Value, _Hash, _Pred, _Alloc>& __c, _Predicate __pred) {
+ return std::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
+ const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y) {
+ if (__x.size() != __y.size())
+ return false;
+ typedef typename unordered_set<_Value, _Hash, _Pred, _Alloc>::const_iterator const_iterator;
+ for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end(); __i != __ex; ++__i) {
+ const_iterator __j = __y.find(*__i);
+ if (__j == __ey || !(*__i == *__j))
+ return false;
+ }
+ return true;
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
+ const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+#endif
+
+template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>, class _Alloc = allocator<_Value> >
+class _LIBCPP_TEMPLATE_VIS unordered_multiset {
+public:
+ // types
+ typedef _Value key_type;
+ typedef key_type value_type;
+ typedef __type_identity_t<_Hash> hasher;
+ typedef __type_identity_t<_Pred> key_equal;
+ typedef __type_identity_t<_Alloc> allocator_type;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ static_assert(is_same<value_type, typename allocator_type::value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+private:
+ typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
+
+ __table __table_;
+
+public:
+ typedef typename __table::pointer pointer;
+ typedef typename __table::const_pointer const_pointer;
+ typedef typename __table::size_type size_type;
+ typedef typename __table::difference_type difference_type;
+
+ typedef typename __table::const_iterator iterator;
+ typedef typename __table::const_iterator const_iterator;
+ typedef typename __table::const_local_iterator local_iterator;
+ typedef typename __table::const_local_iterator const_local_iterator;
+
+#if _LIBCPP_STD_VER >= 17
+ typedef __set_node_handle<typename __table::__node, allocator_type> node_type;
+#endif
+
+ template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_set;
+ template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
+ friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
+
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset() _NOEXCEPT_(is_nothrow_default_constructible<__table>::value) {}
+ explicit _LIBCPP_HIDE_FROM_ABI
+ unordered_multiset(size_type __n, const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_multiset(size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a);
+#if _LIBCPP_STD_VER >= 14
+ inline _LIBCPP_HIDE_FROM_ABI unordered_multiset(size_type __n, const allocator_type& __a)
+ : unordered_multiset(__n, hasher(), key_equal(), __a) {}
+ inline _LIBCPP_HIDE_FROM_ABI unordered_multiset(size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_multiset(__n, __hf, key_equal(), __a) {}
+#endif
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(
+ from_range_t,
+ _Range&& __range,
+ size_type __n = /*implementation-defined*/ 0,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal(),
+ const allocator_type& __a = allocator_type())
+ : __table_(__hf, __eql, __a) {
+ if (__n > 0) {
+ __table_.__rehash_multi(__n);
+ }
+ insert_range(std::forward<_Range>(__range));
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 14
+ template <class _InputIterator>
+ inline _LIBCPP_HIDE_FROM_ABI
+ unordered_multiset(_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type& __a)
+ : unordered_multiset(__first, __last, __n, hasher(), key_equal(), __a) {}
+ template <class _InputIterator>
+ inline _LIBCPP_HIDE_FROM_ABI unordered_multiset(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_multiset(__first, __last, __n, __hf, key_equal(), __a) {}
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(from_range_t, _Range&& __range, size_type __n, const allocator_type& __a)
+ : unordered_multiset(from_range, std::forward<_Range>(__range), __n, hasher(), key_equal(), __a) {}
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI
+ unordered_multiset(from_range_t, _Range&& __range, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_multiset(from_range, std::forward<_Range>(__range), __n, __hf, key_equal(), __a) {}
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI explicit unordered_multiset(const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(const unordered_multiset& __u);
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(const unordered_multiset& __u, const allocator_type& __a);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(unordered_multiset&& __u)
+ _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(unordered_multiset&& __u, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(initializer_list<value_type> __il);
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf = hasher(),
+ const key_equal& __eql = key_equal());
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a);
+# if _LIBCPP_STD_VER >= 14
+ inline _LIBCPP_HIDE_FROM_ABI
+ unordered_multiset(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
+ : unordered_multiset(__il, __n, hasher(), key_equal(), __a) {}
+ inline _LIBCPP_HIDE_FROM_ABI
+ unordered_multiset(initializer_list<value_type> __il, size_type __n, const hasher& __hf, const allocator_type& __a)
+ : unordered_multiset(__il, __n, __hf, key_equal(), __a) {}
+# endif
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI ~unordered_multiset() {
+ static_assert(sizeof(std::__diagnose_unordered_container_requirements<_Value, _Hash, _Pred>(0)), "");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset& operator=(const unordered_multiset& __u) {
+ __table_ = __u.__table_;
+ return *this;
+ }
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset& operator=(unordered_multiset&& __u)
+ _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
+ _LIBCPP_HIDE_FROM_ABI unordered_multiset& operator=(initializer_list<value_type> __il);
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT {
+ return allocator_type(__table_.__node_alloc());
+ }
+
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT { return __table_.size() == 0; }
+ _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT { return __table_.size(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT { return __table_.max_size(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __table_.end(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return __table_.begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return __table_.end(); }
+
+#ifndef _LIBCPP_CXX03_LANG
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace(_Args&&... __args) {
+ return __table_.__emplace_multi(std::forward<_Args>(__args)...);
+ }
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator __p, _Args&&... __args) {
+ return __table_.__emplace_hint_multi(__p, std::forward<_Args>(__args)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(value_type&& __x) { return __table_.__insert_multi(std::move(__x)); }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __x) {
+ return __table_.__insert_multi(__p, std::move(__x));
+ }
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const value_type& __x) { return __table_.__insert_multi(__x); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __x) {
+ return __table_.__insert_multi(__p, __x);
+ }
+
+ template <class _InputIterator>
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ for (auto&& __element : __range) {
+ __table_.__insert_multi(std::forward<decltype(__element)>(__element));
+ }
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI iterator insert(node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to unordered_multiset::insert()");
+ return __table_.template __node_handle_insert_multi<node_type>(std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, node_type&& __nh) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(__nh.empty() || __nh.get_allocator() == get_allocator(),
+ "node_type with incompatible allocator passed to unordered_multiset::insert()");
+ return __table_.template __node_handle_insert_multi<node_type>(__hint, std::move(__nh));
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(const_iterator __position) {
+ return __table_.template __node_handle_extract<node_type>(__position);
+ }
+ _LIBCPP_HIDE_FROM_ABI node_type extract(key_type const& __key) {
+ return __table_.template __node_handle_extract<node_type>(__key);
+ }
+
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_multi(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_multi(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_set<key_type, _H2, _P2, allocator_type>& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_multi(__source.__table_);
+ }
+ template <class _H2, class _P2>
+ _LIBCPP_HIDE_FROM_ABI void merge(unordered_set<key_type, _H2, _P2, allocator_type>&& __source) {
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __source.get_allocator() == get_allocator(), "merging container with incompatible allocator");
+ return __table_.__node_handle_merge_multi(__source.__table_);
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p) { return __table_.erase(__p); }
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __k) { return __table_.__erase_multi(__k); }
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last) {
+ return __table_.erase(__first, __last);
+ }
+ _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __table_.clear(); }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(unordered_multiset& __u) _NOEXCEPT_(__is_nothrow_swappable_v<__table>) {
+ __table_.swap(__u.__table_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI hasher hash_function() const { return __table_.hash_function(); }
+ _LIBCPP_HIDE_FROM_ABI key_equal key_eq() const { return __table_.key_eq(); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __k) { return __table_.find(__k); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __k) const { return __table_.find(__k); }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _K2& __k) {
+ return __table_.find(__k);
+ }
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _K2& __k) const {
+ return __table_.find(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __k) const { return __table_.__count_multi(__k); }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _K2& __k) const {
+ return __table_.__count_multi(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 20
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __k) const { return find(__k) != end(); }
+
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _K2& __k) const {
+ return find(__k) != end();
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __k) {
+ return __table_.__equal_range_multi(__k);
+ }
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __k) const {
+ return __table_.__equal_range_multi(__k);
+ }
+#if _LIBCPP_STD_VER >= 20
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _K2& __k) {
+ return __table_.__equal_range_multi(__k);
+ }
+ template <class _K2, enable_if_t<__is_transparent_v<hasher, _K2> && __is_transparent_v<key_equal, _K2>>* = nullptr>
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _K2& __k) const {
+ return __table_.__equal_range_multi(__k);
+ }
+#endif // _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_count() const _NOEXCEPT { return __table_.bucket_count(); }
+ _LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const _NOEXCEPT { return __table_.max_bucket_count(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type bucket_size(size_type __n) const { return __table_.bucket_size(__n); }
+ _LIBCPP_HIDE_FROM_ABI size_type bucket(const key_type& __k) const { return __table_.bucket(__k); }
+
+ _LIBCPP_HIDE_FROM_ABI local_iterator begin(size_type __n) { return __table_.begin(__n); }
+ _LIBCPP_HIDE_FROM_ABI local_iterator end(size_type __n) { return __table_.end(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator begin(size_type __n) const { return __table_.cbegin(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator end(size_type __n) const { return __table_.cend(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cbegin(size_type __n) const { return __table_.cbegin(__n); }
+ _LIBCPP_HIDE_FROM_ABI const_local_iterator cend(size_type __n) const { return __table_.cend(__n); }
+
+ _LIBCPP_HIDE_FROM_ABI float load_factor() const _NOEXCEPT { return __table_.load_factor(); }
+ _LIBCPP_HIDE_FROM_ABI float max_load_factor() const _NOEXCEPT { return __table_.max_load_factor(); }
+ _LIBCPP_HIDE_FROM_ABI void max_load_factor(float __mlf) { __table_.max_load_factor(__mlf); }
+ _LIBCPP_HIDE_FROM_ABI void rehash(size_type __n) { __table_.__rehash_multi(__n); }
+ _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n) { __table_.__reserve_multi(__n); }
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Hash = hash<__iter_value_type<_InputIterator>>,
+ class _Pred = equal_to<__iter_value_type<_InputIterator>>,
+ class _Allocator = allocator<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(
+ _InputIterator,
+ _InputIterator,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator()) -> unordered_multiset<__iter_value_type<_InputIterator>, _Hash, _Pred, _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Hash = hash<ranges::range_value_t<_Range>>,
+ class _Pred = equal_to<ranges::range_value_t<_Range>>,
+ class _Allocator = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(
+ from_range_t,
+ _Range&&,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator()) -> unordered_multiset<ranges::range_value_t<_Range>, _Hash, _Pred, _Allocator>; // C++23
+# endif
+
+template <class _Tp,
+ class _Hash = hash<_Tp>,
+ class _Pred = equal_to<_Tp>,
+ class _Allocator = allocator<_Tp>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<!__is_allocator<_Pred>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(initializer_list<_Tp>,
+ typename allocator_traits<_Allocator>::size_type = 0,
+ _Hash = _Hash(),
+ _Pred = _Pred(),
+ _Allocator = _Allocator()) -> unordered_multiset<_Tp, _Hash, _Pred, _Allocator>;
+
+template <class _InputIterator,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_multiset<__iter_value_type<_InputIterator>,
+ hash<__iter_value_type<_InputIterator>>,
+ equal_to<__iter_value_type<_InputIterator>>,
+ _Allocator>;
+
+template <class _InputIterator,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_multiset<__iter_value_type<_InputIterator>,
+ _Hash,
+ equal_to<__iter_value_type<_InputIterator>>,
+ _Allocator>;
+
+# if _LIBCPP_STD_VER >= 23
+
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(from_range_t, _Range&&, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_multiset<ranges::range_value_t<_Range>,
+ hash<ranges::range_value_t<_Range>>,
+ equal_to<ranges::range_value_t<_Range>>,
+ _Allocator>;
+
+template <ranges::input_range _Range, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(from_range_t, _Range&&, _Allocator)
+ -> unordered_multiset<ranges::range_value_t<_Range>,
+ hash<ranges::range_value_t<_Range>>,
+ equal_to<ranges::range_value_t<_Range>>,
+ _Allocator>;
+
+template <ranges::input_range _Range,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(from_range_t, _Range&&, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_multiset<ranges::range_value_t<_Range>, _Hash, equal_to<ranges::range_value_t<_Range>>, _Allocator>;
+
+# endif
+
+template <class _Tp, class _Allocator, class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Allocator)
+ -> unordered_multiset<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
+
+template <class _Tp,
+ class _Hash,
+ class _Allocator,
+ class = enable_if_t<!__is_allocator<_Hash>::value>,
+ class = enable_if_t<!is_integral<_Hash>::value>,
+ class = enable_if_t<__is_allocator<_Allocator>::value>>
+unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
+ -> unordered_multiset<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
+#endif
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
+ size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
+ size_type __n, const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_multi(__n);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(_InputIterator __first, _InputIterator __last) {
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
+ _InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
+ _InputIterator __first,
+ _InputIterator __last,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_multi(__n);
+ insert(__first, __last);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(const allocator_type& __a)
+ : __table_(__a) {}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(const unordered_multiset& __u)
+ : __table_(__u.__table_) {
+ __table_.__rehash_multi(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
+ const unordered_multiset& __u, const allocator_type& __a)
+ : __table_(__u.__table_, __a) {
+ __table_.__rehash_multi(__u.bucket_count());
+ insert(__u.begin(), __u.end());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(unordered_multiset&& __u)
+ _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
+ : __table_(std::move(__u.__table_)) {}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
+ unordered_multiset&& __u, const allocator_type& __a)
+ : __table_(std::move(__u.__table_), __a) {
+ if (__a != __u.get_allocator()) {
+ iterator __i = __u.begin();
+ while (__u.size() != 0)
+ __table_.__insert_multi(std::move(__u.__table_.remove(__i++)->__get_value()));
+ }
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(initializer_list<value_type> __il) {
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
+ initializer_list<value_type> __il, size_type __n, const hasher& __hf, const key_equal& __eql)
+ : __table_(__hf, __eql) {
+ __table_.__rehash_multi(__n);
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
+ initializer_list<value_type> __il,
+ size_type __n,
+ const hasher& __hf,
+ const key_equal& __eql,
+ const allocator_type& __a)
+ : __table_(__hf, __eql, __a) {
+ __table_.__rehash_multi(__n);
+ insert(__il.begin(), __il.end());
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(unordered_multiset&& __u)
+ _NOEXCEPT_(is_nothrow_move_assignable<__table>::value) {
+ __table_ = std::move(__u.__table_);
+ return *this;
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
+unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(initializer_list<value_type> __il) {
+ __table_.__assign_multi(__il.begin(), __il.end());
+ return *this;
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+template <class _InputIterator>
+inline void unordered_multiset<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first, _InputIterator __last) {
+ for (; __first != __last; ++__first)
+ __table_.__insert_multi(*__first);
+}
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI void
+swap(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x, unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
+ _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Value, class _Hash, class _Pred, class _Alloc, class _Predicate>
+inline _LIBCPP_HIDE_FROM_ABI typename unordered_multiset<_Value, _Hash, _Pred, _Alloc>::size_type
+erase_if(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __c, _Predicate __pred) {
+ return std::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+_LIBCPP_HIDE_FROM_ABI bool operator==(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
+ const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y) {
+ if (__x.size() != __y.size())
+ return false;
+ typedef typename unordered_multiset<_Value, _Hash, _Pred, _Alloc>::const_iterator const_iterator;
+ typedef pair<const_iterator, const_iterator> _EqRng;
+ for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;) {
+ _EqRng __xeq = __x.equal_range(*__i);
+ _EqRng __yeq = __y.equal_range(*__i);
+ if (std::distance(__xeq.first, __xeq.second) != std::distance(__yeq.first, __yeq.second) ||
+ !std::is_permutation(__xeq.first, __xeq.second, __yeq.first))
+ return false;
+ __i = __xeq.second;
+ }
+ return true;
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Value, class _Hash, class _Pred, class _Alloc>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
+ const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y) {
+ return !(__x == __y);
+}
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _KeyT, class _HashT = std::hash<_KeyT>, class _PredT = std::equal_to<_KeyT>>
+using unordered_set _LIBCPP_AVAILABILITY_PMR = std::unordered_set<_KeyT, _HashT, _PredT, polymorphic_allocator<_KeyT>>;
+
+template <class _KeyT, class _HashT = std::hash<_KeyT>, class _PredT = std::equal_to<_KeyT>>
+using unordered_multiset _LIBCPP_AVAILABILITY_PMR =
+ std::unordered_multiset<_KeyT, _HashT, _PredT, polymorphic_allocator<_KeyT>>;
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <concepts>
+# include <cstdlib>
+# include <functional>
+# include <iterator>
+# include <stdexcept>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_UNORDERED_SET
diff --git a/libcxx/include/__cxx03/utility b/libcxx/include/__cxx03/utility
new file mode 100644
index 00000000000000..f97907fbf72e9d
--- /dev/null
+++ b/libcxx/include/__cxx03/utility
@@ -0,0 +1,309 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_UTILITY
+#define _LIBCPP_UTILITY
+
+/*
+ utility synopsis
+
+#include <initializer_list>
+
+namespace std
+{
+
+template <class T>
+ void
+ swap(T& a, T& b);
+
+namespace rel_ops
+{
+ template<class T> bool operator!=(const T&, const T&);
+ template<class T> bool operator> (const T&, const T&);
+ template<class T> bool operator<=(const T&, const T&);
+ template<class T> bool operator>=(const T&, const T&);
+}
+
+template<class T>
+void
+swap(T& a, T& b) noexcept(is_nothrow_move_constructible<T>::value &&
+ is_nothrow_move_assignable<T>::value);
+
+template <class T, size_t N>
+void
+swap(T (&a)[N], T (&b)[N]) noexcept(noexcept(swap(*a, *b)));
+
+template <class T> T&& forward(typename remove_reference<T>::type& t) noexcept; // constexpr in C++14
+template <class T> T&& forward(typename remove_reference<T>::type&& t) noexcept; // constexpr in C++14
+
+template <typename T>
+[[nodiscard]] constexpr
+auto forward_like(auto&& x) noexcept -> see below; // since C++23
+
+template <class T> typename remove_reference<T>::type&& move(T&&) noexcept; // constexpr in C++14
+
+template <class T>
+ typename conditional
+ <
+ !is_nothrow_move_constructible<T>::value && is_copy_constructible<T>::value,
+ const T&,
+ T&&
+ >::type
+ move_if_noexcept(T& x) noexcept; // constexpr in C++14
+
+template <class T> constexpr add_const_t<T>& as_const(T& t) noexcept; // C++17
+template <class T> void as_const(const T&&) = delete; // C++17
+
+template <class T> typename add_rvalue_reference<T>::type declval() noexcept;
+
+template<class T, class U> constexpr bool cmp_equal(T t, U u) noexcept; // C++20
+template<class T, class U> constexpr bool cmp_not_equal(T t, U u) noexcept; // C++20
+template<class T, class U> constexpr bool cmp_less(T t, U u) noexcept; // C++20
+template<class T, class U> constexpr bool cmp_greater(T t, U u) noexcept; // C++20
+template<class T, class U> constexpr bool cmp_less_equal(T t, U u) noexcept; // C++20
+template<class T, class U> constexpr bool cmp_greater_equal(T t, U u) noexcept; // C++20
+template<class R, class T> constexpr bool in_range(T t) noexcept; // C++20
+
+template <class T1, class T2>
+struct pair
+{
+ typedef T1 first_type;
+ typedef T2 second_type;
+
+ T1 first;
+ T2 second;
+
+ pair(const pair&) = default;
+ pair(pair&&) = default;
+ explicit(see-below) constexpr pair();
+ explicit(see-below) pair(const T1& x, const T2& y); // constexpr in C++14
+ template <class U = T1, class V = T2> explicit(see-below) pair(U&&, V&&); // constexpr in C++14
+ template <class U, class V> constexpr explicit(see-below) pair(pair<U, V>&); // since C++23
+ template <class U, class V> explicit(see-below) pair(const pair<U, V>& p); // constexpr in C++14
+ template <class U, class V> explicit(see-below) pair(pair<U, V>&& p); // constexpr in C++14
+ template <class U, class V>
+ constexpr explicit(see-below) pair(const pair<U, V>&&); // since C++23
+ template <pair-like P> constexpr explicit(see-below) pair(P&&); // since C++23
+ template <class... Args1, class... Args2>
+ pair(piecewise_construct_t, tuple<Args1...> first_args, // constexpr in C++20
+ tuple<Args2...> second_args);
+
+ constexpr const pair& operator=(const pair& p) const; // since C++23
+ template <class U, class V> pair& operator=(const pair<U, V>& p); // constexpr in C++20
+ template <class U, class V>
+ constexpr const pair& operator=(const pair<U, V>& p) const; // since C++23
+ pair& operator=(pair&& p) noexcept(is_nothrow_move_assignable<T1>::value &&
+ is_nothrow_move_assignable<T2>::value); // constexpr in C++20
+ constexpr const pair& operator=(pair&& p) const; // since C++23
+ template <class U, class V> pair& operator=(pair<U, V>&& p); // constexpr in C++20
+ template <class U, class V>
+ constexpr const pair& operator=(pair<U, V>&& p) const; // since C++23
+ template <pair-like P> constexpr pair& operator=(P&&); // since C++23
+ template <pair-like P> constexpr const pair& operator=(P&&) const; // since C++23
+
+ void swap(pair& p) noexcept(is_nothrow_swappable_v<T1> &&
+ is_nothrow_swappable_v<T2>); // constexpr in C++20
+ constexpr void swap(const pair& p) const noexcept(see below); // since C++23
+};
+
+template<class T1, class T2, class U1, class U2, template<class> class TQual, template<class> class UQual>
+struct basic_common_reference<pair<T1, T2>, pair<U1, U2>, TQual, UQual>; // since C++23
+
+template<class T1, class T2, class U1, class U2>
+struct common_type<pair<T1, T2>, pair<U1, U2>>; // since C++23
+
+template<class T1, class T2> pair(T1, T2) -> pair<T1, T2>;
+
+template <class T1, class T2, class U1, class U2>
+bool operator==(const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14
+template <class T1, class T2, class U1, class U2>
+bool operator!=(const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20
+template <class T1, class T2, class U1, class U2>
+bool operator< (const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20
+template <class T1, class T2, class U1, class U2>
+bool operator> (const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20
+template <class T1, class T2, class U1, class U2>
+bool operator>=(const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20
+template <class T1, class T2, class U1, class U2>
+bool operator<=(const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20
+template <class T1, class T2, class U1, class U2>
+ constexpr common_comparison_type_t<synth-three-way-result<T1,U1>,
+ synth-three-way-result<T2,U2>>
+ operator<=>(const pair<T1,T2>&, const pair<U1,U2>&); // C++20
+
+template <class T1, class T2> pair<V1, V2> make_pair(T1&&, T2&&); // constexpr in C++14
+template <class T1, class T2>
+void
+swap(pair<T1, T2>& x, pair<T1, T2>& y) noexcept(noexcept(x.swap(y))); // constexpr in C++20
+
+template<class T1, class T2> // since C++23
+constexpr void swap(const pair<T1, T2>& x, const pair<T1, T2>& y) noexcept(noexcept(x.swap(y)));
+
+struct piecewise_construct_t { explicit piecewise_construct_t() = default; };
+inline constexpr piecewise_construct_t piecewise_construct = piecewise_construct_t();
+
+template <class T> struct tuple_size;
+template <size_t I, class T> struct tuple_element;
+
+template <class T1, class T2> struct tuple_size<pair<T1, T2> >;
+template <class T1, class T2> struct tuple_element<0, pair<T1, T2> >;
+template <class T1, class T2> struct tuple_element<1, pair<T1, T2> >;
+
+template<size_t I, class T1, class T2>
+ typename tuple_element<I, pair<T1, T2> >::type&
+ get(pair<T1, T2>&) noexcept; // constexpr in C++14
+
+template<size_t I, class T1, class T2>
+ const typename tuple_element<I, pair<T1, T2> >::type&
+ get(const pair<T1, T2>&) noexcept; // constexpr in C++14
+
+template<size_t I, class T1, class T2>
+ typename tuple_element<I, pair<T1, T2> >::type&&
+ get(pair<T1, T2>&&) noexcept; // constexpr in C++14
+
+template<size_t I, class T1, class T2>
+ const typename tuple_element<I, pair<T1, T2> >::type&&
+ get(const pair<T1, T2>&&) noexcept; // constexpr in C++14
+
+template<class T1, class T2>
+ constexpr T1& get(pair<T1, T2>&) noexcept; // C++14
+
+template<class T1, class T2>
+ constexpr const T1& get(const pair<T1, T2>&) noexcept; // C++14
+
+template<class T1, class T2>
+ constexpr T1&& get(pair<T1, T2>&&) noexcept; // C++14
+
+template<class T1, class T2>
+ constexpr const T1&& get(const pair<T1, T2>&&) noexcept; // C++14
+
+template<class T1, class T2>
+ constexpr T1& get(pair<T2, T1>&) noexcept; // C++14
+
+template<class T1, class T2>
+ constexpr const T1& get(const pair<T2, T1>&) noexcept; // C++14
+
+template<class T1, class T2>
+ constexpr T1&& get(pair<T2, T1>&&) noexcept; // C++14
+
+template<class T1, class T2>
+ constexpr const T1&& get(const pair<T2, T1>&&) noexcept; // C++14
+
+// C++14
+
+template<class T, T... I>
+struct integer_sequence
+{
+ typedef T value_type;
+
+ static constexpr size_t size() noexcept;
+};
+
+template<size_t... I>
+ using index_sequence = integer_sequence<size_t, I...>;
+
+template<class T, T N>
+ using make_integer_sequence = integer_sequence<T, 0, 1, ..., N-1>;
+template<size_t N>
+ using make_index_sequence = make_integer_sequence<size_t, N>;
+
+template<class... T>
+ using index_sequence_for = make_index_sequence<sizeof...(T)>;
+
+template<class T, class U=T>
+ constexpr T exchange(T& obj, U&& new_value) // constexpr in C++17, noexcept in C++23
+ noexcept(is_nothrow_move_constructible<T>::value && is_nothrow_assignable<T&, U>::value);
+
+// 20.2.7, in-place construction // C++17
+struct in_place_t {
+ explicit in_place_t() = default;
+};
+inline constexpr in_place_t in_place{};
+template <class T>
+ struct in_place_type_t {
+ explicit in_place_type_t() = default;
+ };
+template <class T>
+ inline constexpr in_place_type_t<T> in_place_type{};
+template <size_t I>
+ struct in_place_index_t {
+ explicit in_place_index_t() = default;
+ };
+template <size_t I>
+ inline constexpr in_place_index_t<I> in_place_index{};
+
+// [utility.underlying], to_underlying
+template <class T>
+ constexpr underlying_type_t<T> to_underlying( T value ) noexcept; // C++23
+
+} // std
+
+*/
+
+#include <__config>
+
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/piecewise_construct.h>
+#include <__utility/rel_ops.h>
+#include <__utility/swap.h>
+
+#if _LIBCPP_STD_VER >= 14
+# include <__utility/exchange.h>
+# include <__utility/integer_sequence.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+# include <__utility/as_const.h>
+# include <__utility/in_place.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+# include <__utility/cmp.h>
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+# include <__utility/forward_like.h>
+# include <__utility/to_underlying.h>
+# include <__utility/unreachable.h>
+#endif
+
+#include <version>
+
+// standard-mandated includes
+
+// [utility.syn]
+#include <compare>
+#include <initializer_list>
+
+// [tuple.creation]
+
+#include <__tuple/ignore.h>
+
+// [tuple.helper]
+#include <__tuple/tuple_element.h>
+#include <__tuple/tuple_size.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <limits>
+#endif
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <cstdlib>
+# include <iosfwd>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_UTILITY
diff --git a/libcxx/include/__cxx03/valarray b/libcxx/include/__cxx03/valarray
new file mode 100644
index 00000000000000..44341eb2ba6c14
--- /dev/null
+++ b/libcxx/include/__cxx03/valarray
@@ -0,0 +1,3364 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_VALARRAY
+#define _LIBCPP_VALARRAY
+
+/*
+ valarray synopsis
+
+namespace std
+{
+
+template<class T>
+class valarray
+{
+public:
+ typedef T value_type;
+
+ // construct/destroy:
+ valarray();
+ explicit valarray(size_t n);
+ valarray(const value_type& x, size_t n);
+ valarray(const value_type* px, size_t n);
+ valarray(const valarray& v);
+ valarray(valarray&& v) noexcept;
+ valarray(const slice_array<value_type>& sa);
+ valarray(const gslice_array<value_type>& ga);
+ valarray(const mask_array<value_type>& ma);
+ valarray(const indirect_array<value_type>& ia);
+ valarray(initializer_list<value_type> il);
+ ~valarray();
+
+ // assignment:
+ valarray& operator=(const valarray& v);
+ valarray& operator=(valarray&& v) noexcept;
+ valarray& operator=(initializer_list<value_type> il);
+ valarray& operator=(const value_type& x);
+ valarray& operator=(const slice_array<value_type>& sa);
+ valarray& operator=(const gslice_array<value_type>& ga);
+ valarray& operator=(const mask_array<value_type>& ma);
+ valarray& operator=(const indirect_array<value_type>& ia);
+
+ // element access:
+ const value_type& operator[](size_t i) const;
+ value_type& operator[](size_t i);
+
+ // subset operations:
+ valarray operator[](slice s) const;
+ slice_array<value_type> operator[](slice s);
+ valarray operator[](const gslice& gs) const;
+ gslice_array<value_type> operator[](const gslice& gs);
+ valarray operator[](const valarray<bool>& vb) const;
+ mask_array<value_type> operator[](const valarray<bool>& vb);
+ valarray operator[](const valarray<size_t>& vs) const;
+ indirect_array<value_type> operator[](const valarray<size_t>& vs);
+
+ // unary operators:
+ valarray operator+() const;
+ valarray operator-() const;
+ valarray operator~() const;
+ valarray<bool> operator!() const;
+
+ // computed assignment:
+ valarray& operator*= (const value_type& x);
+ valarray& operator/= (const value_type& x);
+ valarray& operator%= (const value_type& x);
+ valarray& operator+= (const value_type& x);
+ valarray& operator-= (const value_type& x);
+ valarray& operator^= (const value_type& x);
+ valarray& operator&= (const value_type& x);
+ valarray& operator|= (const value_type& x);
+ valarray& operator<<=(const value_type& x);
+ valarray& operator>>=(const value_type& x);
+
+ valarray& operator*= (const valarray& v);
+ valarray& operator/= (const valarray& v);
+ valarray& operator%= (const valarray& v);
+ valarray& operator+= (const valarray& v);
+ valarray& operator-= (const valarray& v);
+ valarray& operator^= (const valarray& v);
+ valarray& operator|= (const valarray& v);
+ valarray& operator&= (const valarray& v);
+ valarray& operator<<=(const valarray& v);
+ valarray& operator>>=(const valarray& v);
+
+ // member functions:
+ void swap(valarray& v) noexcept;
+
+ size_t size() const;
+
+ value_type sum() const;
+ value_type min() const;
+ value_type max() const;
+
+ valarray shift (int i) const;
+ valarray cshift(int i) const;
+ valarray apply(value_type f(value_type)) const;
+ valarray apply(value_type f(const value_type&)) const;
+ void resize(size_t n, value_type x = value_type());
+};
+
+template<class T, size_t cnt> valarray(const T(&)[cnt], size_t) -> valarray<T>;
+
+class slice
+{
+public:
+ slice();
+ slice(size_t start, size_t size, size_t stride);
+
+ size_t start() const;
+ size_t size() const;
+ size_t stride() const;
+
+ friend bool operator==(const slice& x, const slice& y); // since C++20
+};
+
+template <class T>
+class slice_array
+{
+public:
+ typedef T value_type;
+
+ const slice_array& operator=(const slice_array& sa) const;
+ void operator= (const valarray<value_type>& v) const;
+ void operator*= (const valarray<value_type>& v) const;
+ void operator/= (const valarray<value_type>& v) const;
+ void operator%= (const valarray<value_type>& v) const;
+ void operator+= (const valarray<value_type>& v) const;
+ void operator-= (const valarray<value_type>& v) const;
+ void operator^= (const valarray<value_type>& v) const;
+ void operator&= (const valarray<value_type>& v) const;
+ void operator|= (const valarray<value_type>& v) const;
+ void operator<<=(const valarray<value_type>& v) const;
+ void operator>>=(const valarray<value_type>& v) const;
+
+ void operator=(const value_type& x) const;
+ void operator=(const valarray<T>& val_arr) const;
+
+ slice_array() = delete;
+};
+
+class gslice
+{
+public:
+ gslice();
+ gslice(size_t start, const valarray<size_t>& size,
+ const valarray<size_t>& stride);
+
+ size_t start() const;
+ valarray<size_t> size() const;
+ valarray<size_t> stride() const;
+};
+
+template <class T>
+class gslice_array
+{
+public:
+ typedef T value_type;
+
+ void operator= (const valarray<value_type>& v) const;
+ void operator*= (const valarray<value_type>& v) const;
+ void operator/= (const valarray<value_type>& v) const;
+ void operator%= (const valarray<value_type>& v) const;
+ void operator+= (const valarray<value_type>& v) const;
+ void operator-= (const valarray<value_type>& v) const;
+ void operator^= (const valarray<value_type>& v) const;
+ void operator&= (const valarray<value_type>& v) const;
+ void operator|= (const valarray<value_type>& v) const;
+ void operator<<=(const valarray<value_type>& v) const;
+ void operator>>=(const valarray<value_type>& v) const;
+
+ gslice_array(const gslice_array& ga);
+ ~gslice_array();
+ const gslice_array& operator=(const gslice_array& ga) const;
+ void operator=(const value_type& x) const;
+
+ gslice_array() = delete;
+};
+
+template <class T>
+class mask_array
+{
+public:
+ typedef T value_type;
+
+ void operator= (const valarray<value_type>& v) const;
+ void operator*= (const valarray<value_type>& v) const;
+ void operator/= (const valarray<value_type>& v) const;
+ void operator%= (const valarray<value_type>& v) const;
+ void operator+= (const valarray<value_type>& v) const;
+ void operator-= (const valarray<value_type>& v) const;
+ void operator^= (const valarray<value_type>& v) const;
+ void operator&= (const valarray<value_type>& v) const;
+ void operator|= (const valarray<value_type>& v) const;
+ void operator<<=(const valarray<value_type>& v) const;
+ void operator>>=(const valarray<value_type>& v) const;
+
+ mask_array(const mask_array& ma);
+ ~mask_array();
+ const mask_array& operator=(const mask_array& ma) const;
+ void operator=(const value_type& x) const;
+
+ mask_array() = delete;
+};
+
+template <class T>
+class indirect_array
+{
+public:
+ typedef T value_type;
+
+ void operator= (const valarray<value_type>& v) const;
+ void operator*= (const valarray<value_type>& v) const;
+ void operator/= (const valarray<value_type>& v) const;
+ void operator%= (const valarray<value_type>& v) const;
+ void operator+= (const valarray<value_type>& v) const;
+ void operator-= (const valarray<value_type>& v) const;
+ void operator^= (const valarray<value_type>& v) const;
+ void operator&= (const valarray<value_type>& v) const;
+ void operator|= (const valarray<value_type>& v) const;
+ void operator<<=(const valarray<value_type>& v) const;
+ void operator>>=(const valarray<value_type>& v) const;
+
+ indirect_array(const indirect_array& ia);
+ ~indirect_array();
+ const indirect_array& operator=(const indirect_array& ia) const;
+ void operator=(const value_type& x) const;
+
+ indirect_array() = delete;
+};
+
+template<class T> void swap(valarray<T>& x, valarray<T>& y) noexcept;
+
+template<class T> valarray<T> operator* (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator* (const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator* (const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator/ (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator/ (const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator/ (const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator% (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator% (const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator% (const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator+ (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator+ (const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator+ (const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator- (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator- (const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator- (const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator^ (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator^ (const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator^ (const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator& (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator& (const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator& (const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator| (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator| (const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator| (const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator<<(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator<<(const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator<<(const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> operator>>(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> operator>>(const valarray<T>& x, const T& y);
+template<class T> valarray<T> operator>>(const T& x, const valarray<T>& y);
+
+template<class T> valarray<bool> operator&&(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<bool> operator&&(const valarray<T>& x, const T& y);
+template<class T> valarray<bool> operator&&(const T& x, const valarray<T>& y);
+
+template<class T> valarray<bool> operator||(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<bool> operator||(const valarray<T>& x, const T& y);
+template<class T> valarray<bool> operator||(const T& x, const valarray<T>& y);
+
+template<class T> valarray<bool> operator==(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<bool> operator==(const valarray<T>& x, const T& y);
+template<class T> valarray<bool> operator==(const T& x, const valarray<T>& y);
+
+template<class T> valarray<bool> operator!=(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<bool> operator!=(const valarray<T>& x, const T& y);
+template<class T> valarray<bool> operator!=(const T& x, const valarray<T>& y);
+
+template<class T> valarray<bool> operator< (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<bool> operator< (const valarray<T>& x, const T& y);
+template<class T> valarray<bool> operator< (const T& x, const valarray<T>& y);
+
+template<class T> valarray<bool> operator> (const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<bool> operator> (const valarray<T>& x, const T& y);
+template<class T> valarray<bool> operator> (const T& x, const valarray<T>& y);
+
+template<class T> valarray<bool> operator<=(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<bool> operator<=(const valarray<T>& x, const T& y);
+template<class T> valarray<bool> operator<=(const T& x, const valarray<T>& y);
+
+template<class T> valarray<bool> operator>=(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<bool> operator>=(const valarray<T>& x, const T& y);
+template<class T> valarray<bool> operator>=(const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> abs (const valarray<T>& x);
+template<class T> valarray<T> acos (const valarray<T>& x);
+template<class T> valarray<T> asin (const valarray<T>& x);
+template<class T> valarray<T> atan (const valarray<T>& x);
+
+template<class T> valarray<T> atan2(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> atan2(const valarray<T>& x, const T& y);
+template<class T> valarray<T> atan2(const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> cos (const valarray<T>& x);
+template<class T> valarray<T> cosh (const valarray<T>& x);
+template<class T> valarray<T> exp (const valarray<T>& x);
+template<class T> valarray<T> log (const valarray<T>& x);
+template<class T> valarray<T> log10(const valarray<T>& x);
+
+template<class T> valarray<T> pow(const valarray<T>& x, const valarray<T>& y);
+template<class T> valarray<T> pow(const valarray<T>& x, const T& y);
+template<class T> valarray<T> pow(const T& x, const valarray<T>& y);
+
+template<class T> valarray<T> sin (const valarray<T>& x);
+template<class T> valarray<T> sinh (const valarray<T>& x);
+template<class T> valarray<T> sqrt (const valarray<T>& x);
+template<class T> valarray<T> tan (const valarray<T>& x);
+template<class T> valarray<T> tanh (const valarray<T>& x);
+
+template <class T> unspecified1 begin(valarray<T>& v);
+template <class T> unspecified2 begin(const valarray<T>& v);
+template <class T> unspecified1 end(valarray<T>& v);
+template <class T> unspecified2 end(const valarray<T>& v);
+
+} // std
+
+*/
+
+#include <__algorithm/copy.h>
+#include <__algorithm/count.h>
+#include <__algorithm/fill.h>
+#include <__algorithm/max_element.h>
+#include <__algorithm/min.h>
+#include <__algorithm/min_element.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__assert>
+#include <__config>
+#include <__functional/operations.h>
+#include <__memory/addressof.h>
+#include <__memory/allocator.h>
+#include <__memory/uninitialized_algorithms.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <cmath>
+#include <cstddef>
+#include <new>
+#include <version>
+
+// standard-mandated includes
+
+// [valarray.syn]
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS valarray;
+
+class _LIBCPP_TEMPLATE_VIS slice {
+ size_t __start_;
+ size_t __size_;
+ size_t __stride_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI slice() : __start_(0), __size_(0), __stride_(0) {}
+
+ _LIBCPP_HIDE_FROM_ABI slice(size_t __start, size_t __size, size_t __stride)
+ : __start_(__start), __size_(__size), __stride_(__stride) {}
+
+ _LIBCPP_HIDE_FROM_ABI size_t start() const { return __start_; }
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __size_; }
+ _LIBCPP_HIDE_FROM_ABI size_t stride() const { return __stride_; }
+
+#if _LIBCPP_STD_VER >= 20
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const slice& __x, const slice& __y) {
+ return __x.start() == __y.start() && __x.size() == __y.size() && __x.stride() == __y.stride();
+ }
+
+#endif
+};
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS slice_array;
+class _LIBCPP_EXPORTED_FROM_ABI gslice;
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS gslice_array;
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS mask_array;
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS indirect_array;
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp* begin(valarray<_Tp>& __v);
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI const _Tp* begin(const valarray<_Tp>& __v);
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Tp* end(valarray<_Tp>& __v);
+
+template <class _Tp>
+_LIBCPP_HIDE_FROM_ABI const _Tp* end(const valarray<_Tp>& __v);
+
+template <class _Op, class _A0>
+struct _UnaryOp {
+ typedef typename _Op::__result_type __result_type;
+ using value_type = __decay_t<__result_type>;
+
+ _Op __op_;
+ _A0 __a0_;
+
+ _LIBCPP_HIDE_FROM_ABI _UnaryOp(const _Op& __op, const _A0& __a0) : __op_(__op), __a0_(__a0) {}
+
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __op_(__a0_[__i]); }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __a0_.size(); }
+};
+
+template <class _Op, class _A0, class _A1>
+struct _BinaryOp {
+ typedef typename _Op::__result_type __result_type;
+ using value_type = __decay_t<__result_type>;
+
+ _Op __op_;
+ _A0 __a0_;
+ _A1 __a1_;
+
+ _LIBCPP_HIDE_FROM_ABI _BinaryOp(const _Op& __op, const _A0& __a0, const _A1& __a1)
+ : __op_(__op), __a0_(__a0), __a1_(__a1) {}
+
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __op_(__a0_[__i], __a1_[__i]); }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __a0_.size(); }
+};
+
+template <class _Tp>
+class __scalar_expr {
+public:
+ typedef _Tp value_type;
+ typedef const _Tp& __result_type;
+
+private:
+ const value_type& __t_;
+ size_t __s_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI explicit __scalar_expr(const value_type& __t, size_t __s) : __t_(__t), __s_(__s) {}
+
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t) const { return __t_; }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __s_; }
+};
+
+template <class _Tp>
+struct __unary_plus {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return +__x; }
+};
+
+template <class _Tp>
+struct __bit_not {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return ~__x; }
+};
+
+template <class _Tp>
+struct __bit_shift_left {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const { return __x << __y; }
+};
+
+template <class _Tp>
+struct __bit_shift_right {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const { return __x >> __y; }
+};
+
+template <class _Tp, class _Fp>
+struct __apply_expr {
+private:
+ _Fp __f_;
+
+public:
+ typedef _Tp __result_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __apply_expr(_Fp __f) : __f_(__f) {}
+
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return __f_(__x); }
+};
+
+template <class _Tp>
+struct __abs_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::abs(__x); }
+};
+
+template <class _Tp>
+struct __acos_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::acos(__x); }
+};
+
+template <class _Tp>
+struct __asin_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::asin(__x); }
+};
+
+template <class _Tp>
+struct __atan_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::atan(__x); }
+};
+
+template <class _Tp>
+struct __atan2_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const { return std::atan2(__x, __y); }
+};
+
+template <class _Tp>
+struct __cos_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::cos(__x); }
+};
+
+template <class _Tp>
+struct __cosh_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::cosh(__x); }
+};
+
+template <class _Tp>
+struct __exp_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::exp(__x); }
+};
+
+template <class _Tp>
+struct __log_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::log(__x); }
+};
+
+template <class _Tp>
+struct __log10_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::log10(__x); }
+};
+
+template <class _Tp>
+struct __pow_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x, const _Tp& __y) const { return std::pow(__x, __y); }
+};
+
+template <class _Tp>
+struct __sin_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::sin(__x); }
+};
+
+template <class _Tp>
+struct __sinh_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::sinh(__x); }
+};
+
+template <class _Tp>
+struct __sqrt_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::sqrt(__x); }
+};
+
+template <class _Tp>
+struct __tan_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::tan(__x); }
+};
+
+template <class _Tp>
+struct __tanh_expr {
+ typedef _Tp __result_type;
+ _LIBCPP_HIDE_FROM_ABI _Tp operator()(const _Tp& __x) const { return std::tanh(__x); }
+};
+
+template <class _ValExpr>
+class __slice_expr {
+ typedef __libcpp_remove_reference_t<_ValExpr> _RmExpr;
+
+public:
+ typedef typename _RmExpr::value_type value_type;
+ typedef value_type __result_type;
+
+private:
+ _ValExpr __expr_;
+ size_t __start_;
+ size_t __size_;
+ size_t __stride_;
+
+ _LIBCPP_HIDE_FROM_ABI __slice_expr(const slice& __sl, const _RmExpr& __e)
+ : __expr_(__e), __start_(__sl.start()), __size_(__sl.size()), __stride_(__sl.stride()) {}
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __expr_[__start_ + __i * __stride_]; }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __size_; }
+
+ template <class>
+ friend class __val_expr;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS valarray;
+};
+
+template <class _ValExpr>
+class __mask_expr;
+
+template <class _ValExpr>
+class __indirect_expr;
+
+template <class _ValExpr>
+class __shift_expr {
+ typedef __libcpp_remove_reference_t<_ValExpr> _RmExpr;
+
+public:
+ typedef typename _RmExpr::value_type value_type;
+ typedef value_type __result_type;
+
+private:
+ _ValExpr __expr_;
+ size_t __size_;
+ ptrdiff_t __ul_;
+ ptrdiff_t __sn_;
+ ptrdiff_t __n_;
+ static const ptrdiff_t _Np = static_cast<ptrdiff_t>(sizeof(ptrdiff_t) * __CHAR_BIT__ - 1);
+
+ _LIBCPP_HIDE_FROM_ABI __shift_expr(int __n, const _RmExpr& __e) : __expr_(__e), __size_(__e.size()), __n_(__n) {
+ ptrdiff_t __neg_n = static_cast<ptrdiff_t>(__n_ >> _Np);
+ __sn_ = __neg_n | static_cast<ptrdiff_t>(static_cast<size_t>(-__n_) >> _Np);
+ __ul_ = ((__size_ - __n_) & ~__neg_n) | ((__n_ + 1) & __neg_n);
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __j) const {
+ ptrdiff_t __i = static_cast<ptrdiff_t>(__j);
+ ptrdiff_t __m = (__sn_ * __i - __ul_) >> _Np;
+ return (__expr_[(__i + __n_) & __m] & __m) | (value_type() & ~__m);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __size_; }
+
+ template <class>
+ friend class __val_expr;
+};
+
+template <class _ValExpr>
+class __cshift_expr {
+ typedef __libcpp_remove_reference_t<_ValExpr> _RmExpr;
+
+public:
+ typedef typename _RmExpr::value_type value_type;
+ typedef value_type __result_type;
+
+private:
+ _ValExpr __expr_;
+ size_t __size_;
+ size_t __m_;
+ size_t __o1_;
+ size_t __o2_;
+
+ _LIBCPP_HIDE_FROM_ABI __cshift_expr(int __n, const _RmExpr& __e) : __expr_(__e), __size_(__e.size()) {
+ __n %= static_cast<int>(__size_);
+ if (__n >= 0) {
+ __m_ = __size_ - __n;
+ __o1_ = __n;
+ __o2_ = __n - __size_;
+ } else {
+ __m_ = -__n;
+ __o1_ = __n + __size_;
+ __o2_ = __n;
+ }
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const {
+ if (__i < __m_)
+ return __expr_[__i + __o1_];
+ return __expr_[__i + __o2_];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __size_; }
+
+ template <class>
+ friend class __val_expr;
+};
+
+template <class _ValExpr>
+class __val_expr;
+
+template <class _ValExpr>
+struct __is_val_expr : false_type {};
+
+template <class _ValExpr>
+struct __is_val_expr<__val_expr<_ValExpr> > : true_type {};
+
+template <class _Tp>
+struct __is_val_expr<valarray<_Tp> > : true_type {};
+
+template <class _Tp>
+struct __is_val_expr<slice_array<_Tp> > : true_type {};
+
+template <class _Tp>
+struct __is_val_expr<gslice_array<_Tp> > : true_type {};
+
+template <class _Tp>
+struct __is_val_expr<mask_array<_Tp> > : true_type {};
+
+template <class _Tp>
+struct __is_val_expr<indirect_array<_Tp> > : true_type {};
+
+// The functions using a __val_expr access the elements by their index.
+// valarray and the libc++ lazy proxies have an operator[]. The
+// Standard proxy array's don't have this operator, instead they have a
+// implementation specific accessor
+// __get(size_t)
+//
+// The functions use the non-member function
+// __get(__val_expr, size_t)
+//
+// If the __val_expr is a specialization of __val_expr_use_member_functions it
+// uses the __val_expr's member function
+// __get(size_t)
+// else it uses the __val_expr's member function
+// operator[](size_t)
+template <class _ValExpr>
+struct __val_expr_use_member_functions;
+
+template <class>
+struct __val_expr_use_member_functions : false_type {};
+
+template <class _Tp>
+struct __val_expr_use_member_functions<slice_array<_Tp> > : true_type {};
+
+template <class _Tp>
+struct __val_expr_use_member_functions<gslice_array<_Tp> > : true_type {};
+
+template <class _Tp>
+struct __val_expr_use_member_functions<mask_array<_Tp> > : true_type {};
+
+template <class _Tp>
+struct __val_expr_use_member_functions<indirect_array<_Tp> > : true_type {};
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS valarray {
+public:
+ typedef _Tp value_type;
+ typedef _Tp __result_type;
+
+private:
+ value_type* __begin_;
+ value_type* __end_;
+
+public:
+ // construct/destroy:
+ _LIBCPP_HIDE_FROM_ABI valarray() : __begin_(nullptr), __end_(nullptr) {}
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 explicit valarray(size_t __n);
+ _LIBCPP_HIDE_FROM_ABI valarray(const value_type& __x, size_t __n);
+ valarray(const value_type* __p, size_t __n);
+ valarray(const valarray& __v);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI valarray(valarray&& __v) _NOEXCEPT;
+ valarray(initializer_list<value_type> __il);
+#endif // _LIBCPP_CXX03_LANG
+ valarray(const slice_array<value_type>& __sa);
+ valarray(const gslice_array<value_type>& __ga);
+ valarray(const mask_array<value_type>& __ma);
+ valarray(const indirect_array<value_type>& __ia);
+ inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 ~valarray();
+
+ // assignment:
+ valarray& operator=(const valarray& __v);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI valarray& operator=(valarray&& __v) _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI valarray& operator=(initializer_list<value_type>);
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI valarray& operator=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator=(const slice_array<value_type>& __sa);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator=(const gslice_array<value_type>& __ga);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator=(const mask_array<value_type>& __ma);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator=(const indirect_array<value_type>& __ia);
+ template <class _ValExpr>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator=(const __val_expr<_ValExpr>& __v);
+
+ // element access:
+ _LIBCPP_HIDE_FROM_ABI const value_type& operator[](size_t __i) const { return __begin_[__i]; }
+
+ _LIBCPP_HIDE_FROM_ABI value_type& operator[](size_t __i) { return __begin_[__i]; }
+
+ // subset operations:
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__slice_expr<const valarray&> > operator[](slice __s) const;
+ _LIBCPP_HIDE_FROM_ABI slice_array<value_type> operator[](slice __s);
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__indirect_expr<const valarray&> > operator[](const gslice& __gs) const;
+ _LIBCPP_HIDE_FROM_ABI gslice_array<value_type> operator[](const gslice& __gs);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__indirect_expr<const valarray&> > operator[](gslice&& __gs) const;
+ _LIBCPP_HIDE_FROM_ABI gslice_array<value_type> operator[](gslice&& __gs);
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__mask_expr<const valarray&> > operator[](const valarray<bool>& __vb) const;
+ _LIBCPP_HIDE_FROM_ABI mask_array<value_type> operator[](const valarray<bool>& __vb);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__mask_expr<const valarray&> > operator[](valarray<bool>&& __vb) const;
+ _LIBCPP_HIDE_FROM_ABI mask_array<value_type> operator[](valarray<bool>&& __vb);
+#endif // _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__indirect_expr<const valarray&> > operator[](const valarray<size_t>& __vs) const;
+ _LIBCPP_HIDE_FROM_ABI indirect_array<value_type> operator[](const valarray<size_t>& __vs);
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__indirect_expr<const valarray&> > operator[](valarray<size_t>&& __vs) const;
+ _LIBCPP_HIDE_FROM_ABI indirect_array<value_type> operator[](valarray<size_t>&& __vs);
+#endif // _LIBCPP_CXX03_LANG
+
+ // unary operators:
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__unary_plus<_Tp>, const valarray&> > operator+() const;
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<negate<_Tp>, const valarray&> > operator-() const;
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__bit_not<_Tp>, const valarray&> > operator~() const;
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<logical_not<_Tp>, const valarray&> > operator!() const;
+
+ // computed assignment:
+ _LIBCPP_HIDE_FROM_ABI valarray& operator*=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator/=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator%=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator+=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator-=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator^=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator&=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator|=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator<<=(const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI valarray& operator>>=(const value_type& __x);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator*=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator/=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator%=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator+=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator-=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator^=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator|=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator&=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator<<=(const _Expr& __v);
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI valarray& operator>>=(const _Expr& __v);
+
+ // member functions:
+ _LIBCPP_HIDE_FROM_ABI void swap(valarray& __v) _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return static_cast<size_t>(__end_ - __begin_); }
+
+ _LIBCPP_HIDE_FROM_ABI value_type sum() const;
+ _LIBCPP_HIDE_FROM_ABI value_type min() const;
+ _LIBCPP_HIDE_FROM_ABI value_type max() const;
+
+ valarray shift(int __i) const;
+ valarray cshift(int __i) const;
+ valarray apply(value_type __f(value_type)) const;
+ valarray apply(value_type __f(const value_type&)) const;
+ void resize(size_t __n, value_type __x = value_type());
+
+private:
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS valarray;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS slice_array;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS gslice_array;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS mask_array;
+ template <class>
+ friend class __mask_expr;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS indirect_array;
+ template <class>
+ friend class __indirect_expr;
+ template <class>
+ friend class __val_expr;
+
+ template <class _Up>
+ friend _Up* begin(valarray<_Up>& __v);
+
+ template <class _Up>
+ friend const _Up* begin(const valarray<_Up>& __v);
+
+ template <class _Up>
+ friend _Up* end(valarray<_Up>& __v);
+
+ template <class _Up>
+ friend const _Up* end(const valarray<_Up>& __v);
+
+ _LIBCPP_HIDE_FROM_ABI void __clear(size_t __capacity);
+ valarray& __assign_range(const value_type* __f, const value_type* __l);
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _Tp, size_t _Size>
+valarray(const _Tp (&)[_Size], size_t) -> valarray<_Tp>;
+#endif
+
+template <class _Expr,
+ __enable_if_t<__is_val_expr<_Expr>::value && __val_expr_use_member_functions<_Expr>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI typename _Expr::value_type __get(const _Expr& __v, size_t __i) {
+ return __v.__get(__i);
+}
+
+template <class _Expr,
+ __enable_if_t<__is_val_expr<_Expr>::value && !__val_expr_use_member_functions<_Expr>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI typename _Expr::value_type __get(const _Expr& __v, size_t __i) {
+ return __v[__i];
+}
+
+extern template _LIBCPP_EXPORTED_FROM_ABI void valarray<size_t>::resize(size_t, size_t);
+
+template <class _Op, class _Tp>
+struct _UnaryOp<_Op, valarray<_Tp> > {
+ typedef typename _Op::__result_type __result_type;
+ using value_type = __decay_t<__result_type>;
+
+ _Op __op_;
+ const valarray<_Tp>& __a0_;
+
+ _LIBCPP_HIDE_FROM_ABI _UnaryOp(const _Op& __op, const valarray<_Tp>& __a0) : __op_(__op), __a0_(__a0) {}
+
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __op_(__a0_[__i]); }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __a0_.size(); }
+};
+
+template <class _Op, class _Tp, class _A1>
+struct _BinaryOp<_Op, valarray<_Tp>, _A1> {
+ typedef typename _Op::__result_type __result_type;
+ using value_type = __decay_t<__result_type>;
+
+ _Op __op_;
+ const valarray<_Tp>& __a0_;
+ _A1 __a1_;
+
+ _LIBCPP_HIDE_FROM_ABI _BinaryOp(const _Op& __op, const valarray<_Tp>& __a0, const _A1& __a1)
+ : __op_(__op), __a0_(__a0), __a1_(__a1) {}
+
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __op_(__a0_[__i], __a1_[__i]); }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __a0_.size(); }
+};
+
+template <class _Op, class _A0, class _Tp>
+struct _BinaryOp<_Op, _A0, valarray<_Tp> > {
+ typedef typename _Op::__result_type __result_type;
+ using value_type = __decay_t<__result_type>;
+
+ _Op __op_;
+ _A0 __a0_;
+ const valarray<_Tp>& __a1_;
+
+ _LIBCPP_HIDE_FROM_ABI _BinaryOp(const _Op& __op, const _A0& __a0, const valarray<_Tp>& __a1)
+ : __op_(__op), __a0_(__a0), __a1_(__a1) {}
+
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __op_(__a0_[__i], __a1_[__i]); }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __a0_.size(); }
+};
+
+template <class _Op, class _Tp>
+struct _BinaryOp<_Op, valarray<_Tp>, valarray<_Tp> > {
+ typedef typename _Op::__result_type __result_type;
+ using value_type = __decay_t<__result_type>;
+
+ _Op __op_;
+ const valarray<_Tp>& __a0_;
+ const valarray<_Tp>& __a1_;
+
+ _LIBCPP_HIDE_FROM_ABI _BinaryOp(const _Op& __op, const valarray<_Tp>& __a0, const valarray<_Tp>& __a1)
+ : __op_(__op), __a0_(__a0), __a1_(__a1) {}
+
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __op_(__a0_[__i], __a1_[__i]); }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __a0_.size(); }
+};
+
+// slice_array
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS slice_array {
+public:
+ typedef _Tp value_type;
+
+private:
+ value_type* __vp_;
+ size_t __size_;
+ size_t __stride_;
+
+public:
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator*=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator/=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator%=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator+=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator-=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator^=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator&=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator|=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator<<=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator>>=(const _Expr& __v) const;
+
+ slice_array(slice_array const&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI const slice_array& operator=(const slice_array& __sa) const;
+
+ _LIBCPP_HIDE_FROM_ABI void operator=(const value_type& __x) const;
+
+ _LIBCPP_HIDE_FROM_ABI void operator=(const valarray<value_type>& __va) const;
+
+ // Behaves like __val_expr::operator[], which returns by value.
+ _LIBCPP_HIDE_FROM_ABI value_type __get(size_t __i) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < __size_, "slice_array.__get() index out of bounds");
+ return __vp_[__i * __stride_];
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI slice_array(const slice& __sl, const valarray<value_type>& __v)
+ : __vp_(const_cast<value_type*>(__v.__begin_ + __sl.start())), __size_(__sl.size()), __stride_(__sl.stride()) {}
+
+ template <class>
+ friend class valarray;
+};
+
+template <class _Tp>
+inline const slice_array<_Tp>& slice_array<_Tp>::operator=(const slice_array& __sa) const {
+ value_type* __t = __vp_;
+ const value_type* __s = __sa.__vp_;
+ for (size_t __n = __size_; __n; --__n, __t += __stride_, __s += __sa.__stride_)
+ *__t = *__s;
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t = __v[__i];
+}
+
+template <class _Tp>
+inline void slice_array<_Tp>::operator=(const valarray<value_type>& __va) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __va.size(); ++__i, __t += __stride_)
+ *__t = __va[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator*=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t *= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator/=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t /= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator%=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t %= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator+=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t += __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator-=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t -= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator^=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t ^= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator&=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t &= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator|=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t |= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator<<=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t <<= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void slice_array<_Tp>::operator>>=(const _Expr& __v) const {
+ value_type* __t = __vp_;
+ for (size_t __i = 0; __i < __size_; ++__i, __t += __stride_)
+ *__t >>= __v[__i];
+}
+
+template <class _Tp>
+inline void slice_array<_Tp>::operator=(const value_type& __x) const {
+ value_type* __t = __vp_;
+ for (size_t __n = __size_; __n; --__n, __t += __stride_)
+ *__t = __x;
+}
+
+// gslice
+
+class _LIBCPP_EXPORTED_FROM_ABI gslice {
+ valarray<size_t> __size_;
+ valarray<size_t> __stride_;
+ valarray<size_t> __1d_;
+
+public:
+ _LIBCPP_HIDE_FROM_ABI gslice() {}
+
+ _LIBCPP_HIDE_FROM_ABI gslice(size_t __start, const valarray<size_t>& __size, const valarray<size_t>& __stride)
+ : __size_(__size), __stride_(__stride) {
+ __init(__start);
+ }
+
+#ifndef _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI gslice(size_t __start, const valarray<size_t>& __size, valarray<size_t>&& __stride)
+ : __size_(__size), __stride_(std::move(__stride)) {
+ __init(__start);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI gslice(size_t __start, valarray<size_t>&& __size, const valarray<size_t>& __stride)
+ : __size_(std::move(__size)), __stride_(__stride) {
+ __init(__start);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI gslice(size_t __start, valarray<size_t>&& __size, valarray<size_t>&& __stride)
+ : __size_(std::move(__size)), __stride_(std::move(__stride)) {
+ __init(__start);
+ }
+
+#endif // _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI size_t start() const { return __1d_.size() ? __1d_[0] : 0; }
+
+ _LIBCPP_HIDE_FROM_ABI valarray<size_t> size() const { return __size_; }
+
+ _LIBCPP_HIDE_FROM_ABI valarray<size_t> stride() const { return __stride_; }
+
+private:
+ void __init(size_t __start);
+
+ template <class>
+ friend class gslice_array;
+ template <class>
+ friend class valarray;
+ template <class>
+ friend class __val_expr;
+};
+
+// gslice_array
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS gslice_array {
+public:
+ typedef _Tp value_type;
+
+private:
+ value_type* __vp_;
+ valarray<size_t> __1d_;
+
+public:
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator*=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator/=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator%=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator+=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator-=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator^=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator&=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator|=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator<<=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator>>=(const _Expr& __v) const;
+
+ _LIBCPP_HIDE_FROM_ABI const gslice_array& operator=(const gslice_array& __ga) const;
+
+ _LIBCPP_HIDE_FROM_ABI void operator=(const value_type& __x) const;
+
+ gslice_array(const gslice_array&) = default;
+
+ // Behaves like __val_expr::operator[], which returns by value.
+ _LIBCPP_HIDE_FROM_ABI value_type __get(size_t __i) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < __1d_.size(), "gslice_array.__get() index out of bounds");
+ return __vp_[__1d_[__i]];
+ }
+
+private:
+ gslice_array(const gslice& __gs, const valarray<value_type>& __v)
+ : __vp_(const_cast<value_type*>(__v.__begin_)), __1d_(__gs.__1d_) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+ gslice_array(gslice&& __gs, const valarray<value_type>& __v)
+ : __vp_(const_cast<value_type*>(__v.__begin_)), __1d_(std::move(__gs.__1d_)) {}
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class>
+ friend class valarray;
+};
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] = __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator*=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] *= __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator/=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] /= __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator%=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] %= __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator+=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] += __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator-=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] -= __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator^=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] ^= __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator&=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] &= __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator|=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] |= __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator<<=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] <<= __v[__j];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void gslice_array<_Tp>::operator>>=(const _Expr& __v) const {
+ typedef const size_t* _Ip;
+ size_t __j = 0;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] >>= __v[__j];
+}
+
+template <class _Tp>
+inline const gslice_array<_Tp>& gslice_array<_Tp>::operator=(const gslice_array& __ga) const {
+ typedef const size_t* _Ip;
+ const value_type* __s = __ga.__vp_;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_, __j = __ga.__1d_.__begin_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] = __s[*__j];
+ return *this;
+}
+
+template <class _Tp>
+inline void gslice_array<_Tp>::operator=(const value_type& __x) const {
+ typedef const size_t* _Ip;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i)
+ __vp_[*__i] = __x;
+}
+
+// mask_array
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS mask_array {
+public:
+ typedef _Tp value_type;
+
+private:
+ value_type* __vp_;
+ valarray<size_t> __1d_;
+
+public:
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator*=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator/=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator%=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator+=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator-=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator^=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator&=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator|=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator<<=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator>>=(const _Expr& __v) const;
+
+ mask_array(const mask_array&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI const mask_array& operator=(const mask_array& __ma) const;
+
+ _LIBCPP_HIDE_FROM_ABI void operator=(const value_type& __x) const;
+
+ // Behaves like __val_expr::operator[], which returns by value.
+ _LIBCPP_HIDE_FROM_ABI value_type __get(size_t __i) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < __1d_.size(), "mask_array.__get() index out of bounds");
+ return __vp_[__1d_[__i]];
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI mask_array(const valarray<bool>& __vb, const valarray<value_type>& __v)
+ : __vp_(const_cast<value_type*>(__v.__begin_)),
+ __1d_(static_cast<size_t>(count(__vb.__begin_, __vb.__end_, true))) {
+ size_t __j = 0;
+ for (size_t __i = 0; __i < __vb.size(); ++__i)
+ if (__vb[__i])
+ __1d_[__j++] = __i;
+ }
+
+ template <class>
+ friend class valarray;
+};
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] = __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator*=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] *= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator/=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] /= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator%=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] %= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator+=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] += __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator-=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] -= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator^=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] ^= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator&=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] &= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator|=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] |= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator<<=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] <<= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void mask_array<_Tp>::operator>>=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] >>= __v[__i];
+}
+
+template <class _Tp>
+inline const mask_array<_Tp>& mask_array<_Tp>::operator=(const mask_array& __ma) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] = __ma.__vp_[__1d_[__i]];
+ return *this;
+}
+
+template <class _Tp>
+inline void mask_array<_Tp>::operator=(const value_type& __x) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] = __x;
+}
+
+template <class _ValExpr>
+class __mask_expr {
+ typedef __libcpp_remove_reference_t<_ValExpr> _RmExpr;
+
+public:
+ typedef typename _RmExpr::value_type value_type;
+ typedef value_type __result_type;
+
+private:
+ _ValExpr __expr_;
+ valarray<size_t> __1d_;
+
+ _LIBCPP_HIDE_FROM_ABI __mask_expr(const valarray<bool>& __vb, const _RmExpr& __e)
+ : __expr_(__e), __1d_(static_cast<size_t>(count(__vb.__begin_, __vb.__end_, true))) {
+ size_t __j = 0;
+ for (size_t __i = 0; __i < __vb.size(); ++__i)
+ if (__vb[__i])
+ __1d_[__j++] = __i;
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __expr_[__1d_[__i]]; }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __1d_.size(); }
+
+ template <class>
+ friend class __val_expr;
+ template <class>
+ friend class valarray;
+};
+
+// indirect_array
+
+template <class _Tp>
+class _LIBCPP_TEMPLATE_VIS indirect_array {
+public:
+ typedef _Tp value_type;
+
+private:
+ value_type* __vp_;
+ valarray<size_t> __1d_;
+
+public:
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator*=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator/=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator%=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator+=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator-=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator^=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator&=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator|=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator<<=(const _Expr& __v) const;
+
+ template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI operator>>=(const _Expr& __v) const;
+
+ indirect_array(const indirect_array&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI const indirect_array& operator=(const indirect_array& __ia) const;
+
+ _LIBCPP_HIDE_FROM_ABI void operator=(const value_type& __x) const;
+
+ // Behaves like __val_expr::operator[], which returns by value.
+ _LIBCPP_HIDE_FROM_ABI value_type __get(size_t __i) const {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i < __1d_.size(), "indirect_array.__get() index out of bounds");
+ return __vp_[__1d_[__i]];
+ }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI indirect_array(const valarray<size_t>& __ia, const valarray<value_type>& __v)
+ : __vp_(const_cast<value_type*>(__v.__begin_)), __1d_(__ia) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI indirect_array(valarray<size_t>&& __ia, const valarray<value_type>& __v)
+ : __vp_(const_cast<value_type*>(__v.__begin_)), __1d_(std::move(__ia)) {}
+
+#endif // _LIBCPP_CXX03_LANG
+
+ template <class>
+ friend class valarray;
+};
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] = __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator*=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] *= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator/=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] /= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator%=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] %= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator+=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] += __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator-=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] -= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator^=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] ^= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator&=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] &= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator|=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] |= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator<<=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] <<= __v[__i];
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline void indirect_array<_Tp>::operator>>=(const _Expr& __v) const {
+ size_t __n = __1d_.size();
+ for (size_t __i = 0; __i < __n; ++__i)
+ __vp_[__1d_[__i]] >>= __v[__i];
+}
+
+template <class _Tp>
+inline const indirect_array<_Tp>& indirect_array<_Tp>::operator=(const indirect_array& __ia) const {
+ typedef const size_t* _Ip;
+ const value_type* __s = __ia.__vp_;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_, __j = __ia.__1d_.__begin_; __i != __e; ++__i, ++__j)
+ __vp_[*__i] = __s[*__j];
+ return *this;
+}
+
+template <class _Tp>
+inline void indirect_array<_Tp>::operator=(const value_type& __x) const {
+ typedef const size_t* _Ip;
+ for (_Ip __i = __1d_.__begin_, __e = __1d_.__end_; __i != __e; ++__i)
+ __vp_[*__i] = __x;
+}
+
+template <class _ValExpr>
+class __indirect_expr {
+ typedef __libcpp_remove_reference_t<_ValExpr> _RmExpr;
+
+public:
+ typedef typename _RmExpr::value_type value_type;
+ typedef value_type __result_type;
+
+private:
+ _ValExpr __expr_;
+ valarray<size_t> __1d_;
+
+ _LIBCPP_HIDE_FROM_ABI __indirect_expr(const valarray<size_t>& __ia, const _RmExpr& __e) : __expr_(__e), __1d_(__ia) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI __indirect_expr(valarray<size_t>&& __ia, const _RmExpr& __e)
+ : __expr_(__e), __1d_(std::move(__ia)) {}
+
+#endif // _LIBCPP_CXX03_LANG
+
+public:
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __expr_[__1d_[__i]]; }
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __1d_.size(); }
+
+ template <class>
+ friend class __val_expr;
+ template <class>
+ friend class _LIBCPP_TEMPLATE_VIS valarray;
+};
+
+template <class _ValExpr>
+class __val_expr {
+ typedef __libcpp_remove_reference_t<_ValExpr> _RmExpr;
+
+ _ValExpr __expr_;
+
+public:
+ typedef typename _RmExpr::value_type value_type;
+ typedef typename _RmExpr::__result_type __result_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit __val_expr(const _RmExpr& __e) : __expr_(__e) {}
+
+ _LIBCPP_HIDE_FROM_ABI __result_type operator[](size_t __i) const { return __expr_[__i]; }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__slice_expr<_ValExpr> > operator[](slice __s) const {
+ typedef __slice_expr<_ValExpr> _NewExpr;
+ return __val_expr< _NewExpr >(_NewExpr(__s, __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__indirect_expr<_ValExpr> > operator[](const gslice& __gs) const {
+ typedef __indirect_expr<_ValExpr> _NewExpr;
+ return __val_expr<_NewExpr >(_NewExpr(__gs.__1d_, __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__mask_expr<_ValExpr> > operator[](const valarray<bool>& __vb) const {
+ typedef __mask_expr<_ValExpr> _NewExpr;
+ return __val_expr< _NewExpr >(_NewExpr(__vb, __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__indirect_expr<_ValExpr> > operator[](const valarray<size_t>& __vs) const {
+ typedef __indirect_expr<_ValExpr> _NewExpr;
+ return __val_expr< _NewExpr >(_NewExpr(__vs, __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__unary_plus<value_type>, _ValExpr> > operator+() const {
+ typedef _UnaryOp<__unary_plus<value_type>, _ValExpr> _NewExpr;
+ return __val_expr<_NewExpr>(_NewExpr(__unary_plus<value_type>(), __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<negate<value_type>, _ValExpr> > operator-() const {
+ typedef _UnaryOp<negate<value_type>, _ValExpr> _NewExpr;
+ return __val_expr<_NewExpr>(_NewExpr(negate<value_type>(), __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__bit_not<value_type>, _ValExpr> > operator~() const {
+ typedef _UnaryOp<__bit_not<value_type>, _ValExpr> _NewExpr;
+ return __val_expr<_NewExpr>(_NewExpr(__bit_not<value_type>(), __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<logical_not<value_type>, _ValExpr> > operator!() const {
+ typedef _UnaryOp<logical_not<value_type>, _ValExpr> _NewExpr;
+ return __val_expr<_NewExpr>(_NewExpr(logical_not<value_type>(), __expr_));
+ }
+
+ operator valarray<__result_type>() const;
+
+ _LIBCPP_HIDE_FROM_ABI size_t size() const { return __expr_.size(); }
+
+ _LIBCPP_HIDE_FROM_ABI __result_type sum() const {
+ size_t __n = __expr_.size();
+ __result_type __r = __n ? __expr_[0] : __result_type();
+ for (size_t __i = 1; __i < __n; ++__i)
+ __r += __expr_[__i];
+ return __r;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __result_type min() const {
+ size_t __n = size();
+ __result_type __r = __n ? (*this)[0] : __result_type();
+ for (size_t __i = 1; __i < __n; ++__i) {
+ __result_type __x = __expr_[__i];
+ if (__x < __r)
+ __r = __x;
+ }
+ return __r;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __result_type max() const {
+ size_t __n = size();
+ __result_type __r = __n ? (*this)[0] : __result_type();
+ for (size_t __i = 1; __i < __n; ++__i) {
+ __result_type __x = __expr_[__i];
+ if (__r < __x)
+ __r = __x;
+ }
+ return __r;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__shift_expr<_ValExpr> > shift(int __i) const {
+ return __val_expr<__shift_expr<_ValExpr> >(__shift_expr<_ValExpr>(__i, __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<__cshift_expr<_ValExpr> > cshift(int __i) const {
+ return __val_expr<__cshift_expr<_ValExpr> >(__cshift_expr<_ValExpr>(__i, __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__apply_expr<value_type, value_type (*)(value_type)>, _ValExpr> >
+ apply(value_type __f(value_type)) const {
+ typedef __apply_expr<value_type, value_type (*)(value_type)> _Op;
+ typedef _UnaryOp<_Op, _ValExpr> _NewExpr;
+ return __val_expr<_NewExpr>(_NewExpr(_Op(__f), __expr_));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__apply_expr<value_type, value_type (*)(const value_type&)>, _ValExpr> >
+ apply(value_type __f(const value_type&)) const {
+ typedef __apply_expr<value_type, value_type (*)(const value_type&)> _Op;
+ typedef _UnaryOp<_Op, _ValExpr> _NewExpr;
+ return __val_expr<_NewExpr>(_NewExpr(_Op(__f), __expr_));
+ }
+};
+
+template <class _ValExpr>
+__val_expr<_ValExpr>::operator valarray<__val_expr::__result_type>() const {
+ valarray<__result_type> __r;
+ size_t __n = __expr_.size();
+ if (__n) {
+ __r.__begin_ = __r.__end_ = allocator<__result_type>().allocate(__n);
+ for (size_t __i = 0; __i != __n; ++__r.__end_, ++__i)
+ ::new ((void*)__r.__end_) __result_type(__expr_[__i]);
+ }
+ return __r;
+}
+
+// valarray
+
+template <class _Tp>
+inline valarray<_Tp>::valarray(size_t __n) : __begin_(nullptr), __end_(nullptr) {
+ if (__n) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__n);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (size_t __n_left = __n; __n_left; --__n_left, ++__end_)
+ ::new ((void*)__end_) value_type();
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__n);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp>
+inline valarray<_Tp>::valarray(const value_type& __x, size_t __n) : __begin_(nullptr), __end_(nullptr) {
+ resize(__n, __x);
+}
+
+template <class _Tp>
+valarray<_Tp>::valarray(const value_type* __p, size_t __n) : __begin_(nullptr), __end_(nullptr) {
+ if (__n) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__n);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (size_t __n_left = __n; __n_left; ++__end_, ++__p, --__n_left)
+ ::new ((void*)__end_) value_type(*__p);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__n);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp>
+valarray<_Tp>::valarray(const valarray& __v) : __begin_(nullptr), __end_(nullptr) {
+ if (__v.size()) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__v.size());
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (value_type* __p = __v.__begin_; __p != __v.__end_; ++__end_, ++__p)
+ ::new ((void*)__end_) value_type(*__p);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__v.size());
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline valarray<_Tp>::valarray(valarray&& __v) _NOEXCEPT : __begin_(__v.__begin_), __end_(__v.__end_) {
+ __v.__begin_ = __v.__end_ = nullptr;
+}
+
+template <class _Tp>
+valarray<_Tp>::valarray(initializer_list<value_type> __il) : __begin_(nullptr), __end_(nullptr) {
+ const size_t __n = __il.size();
+ if (__n) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__n);
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ size_t __n_left = __n;
+ for (const value_type* __p = __il.begin(); __n_left; ++__end_, ++__p, --__n_left)
+ ::new ((void*)__end_) value_type(*__p);
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__n);
+ throw;
+ }
+# endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+valarray<_Tp>::valarray(const slice_array<value_type>& __sa) : __begin_(nullptr), __end_(nullptr) {
+ const size_t __n = __sa.__size_;
+ if (__n) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__n);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ size_t __n_left = __n;
+ for (const value_type* __p = __sa.__vp_; __n_left; ++__end_, __p += __sa.__stride_, --__n_left)
+ ::new ((void*)__end_) value_type(*__p);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__n);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp>
+valarray<_Tp>::valarray(const gslice_array<value_type>& __ga) : __begin_(nullptr), __end_(nullptr) {
+ const size_t __n = __ga.__1d_.size();
+ if (__n) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__n);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef const size_t* _Ip;
+ const value_type* __s = __ga.__vp_;
+ for (_Ip __i = __ga.__1d_.__begin_, __e = __ga.__1d_.__end_; __i != __e; ++__i, ++__end_)
+ ::new ((void*)__end_) value_type(__s[*__i]);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__n);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp>
+valarray<_Tp>::valarray(const mask_array<value_type>& __ma) : __begin_(nullptr), __end_(nullptr) {
+ const size_t __n = __ma.__1d_.size();
+ if (__n) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__n);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef const size_t* _Ip;
+ const value_type* __s = __ma.__vp_;
+ for (_Ip __i = __ma.__1d_.__begin_, __e = __ma.__1d_.__end_; __i != __e; ++__i, ++__end_)
+ ::new ((void*)__end_) value_type(__s[*__i]);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__n);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp>
+valarray<_Tp>::valarray(const indirect_array<value_type>& __ia) : __begin_(nullptr), __end_(nullptr) {
+ const size_t __n = __ia.__1d_.size();
+ if (__n) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__n);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ typedef const size_t* _Ip;
+ const value_type* __s = __ia.__vp_;
+ for (_Ip __i = __ia.__1d_.__begin_, __e = __ia.__1d_.__end_; __i != __e; ++__i, ++__end_)
+ ::new ((void*)__end_) value_type(__s[*__i]);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__n);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp>
+inline valarray<_Tp>::~valarray() {
+ __clear(size());
+}
+
+template <class _Tp>
+valarray<_Tp>& valarray<_Tp>::__assign_range(const value_type* __f, const value_type* __l) {
+ size_t __n = __l - __f;
+ if (size() != __n) {
+ __clear(size());
+ __begin_ = allocator<value_type>().allocate(__n);
+ __end_ = __begin_ + __n;
+ std::uninitialized_copy(__f, __l, __begin_);
+ } else {
+ std::copy(__f, __l, __begin_);
+ }
+ return *this;
+}
+
+template <class _Tp>
+valarray<_Tp>& valarray<_Tp>::operator=(const valarray& __v) {
+ if (this != std::addressof(__v))
+ return __assign_range(__v.__begin_, __v.__end_);
+ return *this;
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator=(valarray&& __v) _NOEXCEPT {
+ __clear(size());
+ __begin_ = __v.__begin_;
+ __end_ = __v.__end_;
+ __v.__begin_ = nullptr;
+ __v.__end_ = nullptr;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator=(initializer_list<value_type> __il) {
+ return __assign_range(__il.begin(), __il.end());
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator=(const value_type& __x) {
+ std::fill(__begin_, __end_, __x);
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator=(const slice_array<value_type>& __sa) {
+ value_type* __t = __begin_;
+ const value_type* __s = __sa.__vp_;
+ for (size_t __n = __sa.__size_; __n; --__n, __s += __sa.__stride_, ++__t)
+ *__t = *__s;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator=(const gslice_array<value_type>& __ga) {
+ typedef const size_t* _Ip;
+ value_type* __t = __begin_;
+ const value_type* __s = __ga.__vp_;
+ for (_Ip __i = __ga.__1d_.__begin_, __e = __ga.__1d_.__end_; __i != __e; ++__i, ++__t)
+ *__t = __s[*__i];
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator=(const mask_array<value_type>& __ma) {
+ typedef const size_t* _Ip;
+ value_type* __t = __begin_;
+ const value_type* __s = __ma.__vp_;
+ for (_Ip __i = __ma.__1d_.__begin_, __e = __ma.__1d_.__end_; __i != __e; ++__i, ++__t)
+ *__t = __s[*__i];
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator=(const indirect_array<value_type>& __ia) {
+ typedef const size_t* _Ip;
+ value_type* __t = __begin_;
+ const value_type* __s = __ia.__vp_;
+ for (_Ip __i = __ia.__1d_.__begin_, __e = __ia.__1d_.__end_; __i != __e; ++__i, ++__t)
+ *__t = __s[*__i];
+ return *this;
+}
+
+template <class _Tp>
+template <class _ValExpr>
+inline valarray<_Tp>& valarray<_Tp>::operator=(const __val_expr<_ValExpr>& __v) {
+ size_t __n = __v.size();
+ if (size() != __n)
+ resize(__n);
+ value_type* __t = __begin_;
+ for (size_t __i = 0; __i != __n; ++__t, ++__i)
+ *__t = __result_type(__v[__i]);
+ return *this;
+}
+
+template <class _Tp>
+inline __val_expr<__slice_expr<const valarray<_Tp>&> > valarray<_Tp>::operator[](slice __s) const {
+ return __val_expr<__slice_expr<const valarray&> >(__slice_expr<const valarray&>(__s, *this));
+}
+
+template <class _Tp>
+inline slice_array<_Tp> valarray<_Tp>::operator[](slice __s) {
+ return slice_array<value_type>(__s, *this);
+}
+
+template <class _Tp>
+inline __val_expr<__indirect_expr<const valarray<_Tp>&> > valarray<_Tp>::operator[](const gslice& __gs) const {
+ return __val_expr<__indirect_expr<const valarray&> >(__indirect_expr<const valarray&>(__gs.__1d_, *this));
+}
+
+template <class _Tp>
+inline gslice_array<_Tp> valarray<_Tp>::operator[](const gslice& __gs) {
+ return gslice_array<value_type>(__gs, *this);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline __val_expr<__indirect_expr<const valarray<_Tp>&> > valarray<_Tp>::operator[](gslice&& __gs) const {
+ return __val_expr<__indirect_expr<const valarray&> >(__indirect_expr<const valarray&>(std::move(__gs.__1d_), *this));
+}
+
+template <class _Tp>
+inline gslice_array<_Tp> valarray<_Tp>::operator[](gslice&& __gs) {
+ return gslice_array<value_type>(std::move(__gs), *this);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline __val_expr<__mask_expr<const valarray<_Tp>&> > valarray<_Tp>::operator[](const valarray<bool>& __vb) const {
+ return __val_expr<__mask_expr<const valarray&> >(__mask_expr<const valarray&>(__vb, *this));
+}
+
+template <class _Tp>
+inline mask_array<_Tp> valarray<_Tp>::operator[](const valarray<bool>& __vb) {
+ return mask_array<value_type>(__vb, *this);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline __val_expr<__mask_expr<const valarray<_Tp>&> > valarray<_Tp>::operator[](valarray<bool>&& __vb) const {
+ return __val_expr<__mask_expr<const valarray&> >(__mask_expr<const valarray&>(std::move(__vb), *this));
+}
+
+template <class _Tp>
+inline mask_array<_Tp> valarray<_Tp>::operator[](valarray<bool>&& __vb) {
+ return mask_array<value_type>(std::move(__vb), *this);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline __val_expr<__indirect_expr<const valarray<_Tp>&> >
+valarray<_Tp>::operator[](const valarray<size_t>& __vs) const {
+ return __val_expr<__indirect_expr<const valarray&> >(__indirect_expr<const valarray&>(__vs, *this));
+}
+
+template <class _Tp>
+inline indirect_array<_Tp> valarray<_Tp>::operator[](const valarray<size_t>& __vs) {
+ return indirect_array<value_type>(__vs, *this);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline __val_expr<__indirect_expr<const valarray<_Tp>&> > valarray<_Tp>::operator[](valarray<size_t>&& __vs) const {
+ return __val_expr<__indirect_expr<const valarray&> >(__indirect_expr<const valarray&>(std::move(__vs), *this));
+}
+
+template <class _Tp>
+inline indirect_array<_Tp> valarray<_Tp>::operator[](valarray<size_t>&& __vs) {
+ return indirect_array<value_type>(std::move(__vs), *this);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp>
+inline __val_expr<_UnaryOp<__unary_plus<_Tp>, const valarray<_Tp>&> > valarray<_Tp>::operator+() const {
+ using _Op = _UnaryOp<__unary_plus<_Tp>, const valarray<_Tp>&>;
+ return __val_expr<_Op>(_Op(__unary_plus<_Tp>(), *this));
+}
+
+template <class _Tp>
+inline __val_expr<_UnaryOp<negate<_Tp>, const valarray<_Tp>&> > valarray<_Tp>::operator-() const {
+ using _Op = _UnaryOp<negate<_Tp>, const valarray<_Tp>&>;
+ return __val_expr<_Op>(_Op(negate<_Tp>(), *this));
+}
+
+template <class _Tp>
+inline __val_expr<_UnaryOp<__bit_not<_Tp>, const valarray<_Tp>&> > valarray<_Tp>::operator~() const {
+ using _Op = _UnaryOp<__bit_not<_Tp>, const valarray<_Tp>&>;
+ return __val_expr<_Op>(_Op(__bit_not<_Tp>(), *this));
+}
+
+template <class _Tp>
+inline __val_expr<_UnaryOp<logical_not<_Tp>, const valarray<_Tp>&> > valarray<_Tp>::operator!() const {
+ using _Op = _UnaryOp<logical_not<_Tp>, const valarray<_Tp>&>;
+ return __val_expr<_Op>(_Op(logical_not<_Tp>(), *this));
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator*=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p *= __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator/=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p /= __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator%=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p %= __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator+=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p += __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator-=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p -= __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator^=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p ^= __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator&=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p &= __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator|=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p |= __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator<<=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p <<= __x;
+ return *this;
+}
+
+template <class _Tp>
+inline valarray<_Tp>& valarray<_Tp>::operator>>=(const value_type& __x) {
+ for (value_type* __p = __begin_; __p != __end_; ++__p)
+ *__p >>= __x;
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator*=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t *= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator/=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t /= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator%=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t %= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator+=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t += std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator-=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t -= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator^=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t ^= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator|=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t |= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator&=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t &= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator<<=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t <<= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> >
+inline valarray<_Tp>& valarray<_Tp>::operator>>=(const _Expr& __v) {
+ size_t __i = 0;
+ for (value_type* __t = __begin_; __t != __end_; ++__t, ++__i)
+ *__t >>= std::__get(__v, __i);
+ return *this;
+}
+
+template <class _Tp>
+inline void valarray<_Tp>::swap(valarray& __v) _NOEXCEPT {
+ std::swap(__begin_, __v.__begin_);
+ std::swap(__end_, __v.__end_);
+}
+
+template <class _Tp>
+inline _Tp valarray<_Tp>::sum() const {
+ if (__begin_ == __end_)
+ return value_type();
+ const value_type* __p = __begin_;
+ _Tp __r = *__p;
+ for (++__p; __p != __end_; ++__p)
+ __r += *__p;
+ return __r;
+}
+
+template <class _Tp>
+inline _Tp valarray<_Tp>::min() const {
+ if (__begin_ == __end_)
+ return value_type();
+ return *std::min_element(__begin_, __end_);
+}
+
+template <class _Tp>
+inline _Tp valarray<_Tp>::max() const {
+ if (__begin_ == __end_)
+ return value_type();
+ return *std::max_element(__begin_, __end_);
+}
+
+template <class _Tp>
+valarray<_Tp> valarray<_Tp>::shift(int __i) const {
+ valarray<value_type> __r;
+ size_t __n = size();
+ if (__n) {
+ __r.__begin_ = __r.__end_ = allocator<value_type>().allocate(__n);
+ const value_type* __sb;
+ value_type* __tb;
+ value_type* __te;
+ if (__i >= 0) {
+ __i = std::min(__i, static_cast<int>(__n));
+ __sb = __begin_ + __i;
+ __tb = __r.__begin_;
+ __te = __r.__begin_ + (__n - __i);
+ } else {
+ __i = std::min(-__i, static_cast<int>(__n));
+ __sb = __begin_;
+ __tb = __r.__begin_ + __i;
+ __te = __r.__begin_ + __n;
+ }
+ for (; __r.__end_ != __tb; ++__r.__end_)
+ ::new ((void*)__r.__end_) value_type();
+ for (; __r.__end_ != __te; ++__r.__end_, ++__sb)
+ ::new ((void*)__r.__end_) value_type(*__sb);
+ for (__te = __r.__begin_ + __n; __r.__end_ != __te; ++__r.__end_)
+ ::new ((void*)__r.__end_) value_type();
+ }
+ return __r;
+}
+
+template <class _Tp>
+valarray<_Tp> valarray<_Tp>::cshift(int __i) const {
+ valarray<value_type> __r;
+ size_t __n = size();
+ if (__n) {
+ __r.__begin_ = __r.__end_ = allocator<value_type>().allocate(__n);
+ __i %= static_cast<int>(__n);
+ const value_type* __m = __i >= 0 ? __begin_ + __i : __end_ + __i;
+ for (const value_type* __s = __m; __s != __end_; ++__r.__end_, ++__s)
+ ::new ((void*)__r.__end_) value_type(*__s);
+ for (const value_type* __s = __begin_; __s != __m; ++__r.__end_, ++__s)
+ ::new ((void*)__r.__end_) value_type(*__s);
+ }
+ return __r;
+}
+
+template <class _Tp>
+valarray<_Tp> valarray<_Tp>::apply(value_type __f(value_type)) const {
+ valarray<value_type> __r;
+ size_t __n = size();
+ if (__n) {
+ __r.__begin_ = __r.__end_ = allocator<value_type>().allocate(__n);
+ for (const value_type* __p = __begin_; __n; ++__r.__end_, ++__p, --__n)
+ ::new ((void*)__r.__end_) value_type(__f(*__p));
+ }
+ return __r;
+}
+
+template <class _Tp>
+valarray<_Tp> valarray<_Tp>::apply(value_type __f(const value_type&)) const {
+ valarray<value_type> __r;
+ size_t __n = size();
+ if (__n) {
+ __r.__begin_ = __r.__end_ = allocator<value_type>().allocate(__n);
+ for (const value_type* __p = __begin_; __n; ++__r.__end_, ++__p, --__n)
+ ::new ((void*)__r.__end_) value_type(__f(*__p));
+ }
+ return __r;
+}
+
+template <class _Tp>
+inline void valarray<_Tp>::__clear(size_t __capacity) {
+ if (__begin_ != nullptr) {
+ while (__end_ != __begin_)
+ (--__end_)->~value_type();
+ allocator<value_type>().deallocate(__begin_, __capacity);
+ __begin_ = __end_ = nullptr;
+ }
+}
+
+template <class _Tp>
+void valarray<_Tp>::resize(size_t __n, value_type __x) {
+ __clear(size());
+ if (__n) {
+ __begin_ = __end_ = allocator<value_type>().allocate(__n);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (size_t __n_left = __n; __n_left; --__n_left, ++__end_)
+ ::new ((void*)__end_) value_type(__x);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ __clear(__n);
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI void swap(valarray<_Tp>& __x, valarray<_Tp>& __y) _NOEXCEPT {
+ __x.swap(__y);
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<multiplies<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator*(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<multiplies<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(multiplies<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<multiplies<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator*(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<multiplies<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(multiplies<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<multiplies<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator*(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<multiplies<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(multiplies<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<divides<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator/(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<divides<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(divides<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<divides<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator/(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<divides<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(divides<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<divides<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator/(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<divides<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(divides<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<modulus<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator%(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<modulus<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(modulus<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<modulus<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator%(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<modulus<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(modulus<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<modulus<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator%(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<modulus<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(modulus<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<plus<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator+(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<plus<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(plus<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<plus<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator+(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<plus<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(plus<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<plus<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator+(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<plus<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(plus<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<minus<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator-(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<minus<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(minus<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<minus<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator-(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<minus<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(minus<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<minus<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator-(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<minus<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(minus<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<bit_xor<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator^(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<bit_xor<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(bit_xor<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<bit_xor<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator^(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<bit_xor<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(bit_xor<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<bit_xor<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator^(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<bit_xor<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(bit_xor<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<bit_and<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator&(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<bit_and<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(bit_and<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<bit_and<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator&(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<bit_and<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(bit_and<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<bit_and<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator&(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<bit_and<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(bit_and<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<bit_or<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator|(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<bit_or<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(bit_or<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<bit_or<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator|(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<bit_or<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(bit_or<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<bit_or<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator|(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<bit_or<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(bit_or<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<__bit_shift_left<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator<<(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<__bit_shift_left<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(__bit_shift_left<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr< _BinaryOp<__bit_shift_left<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator<<(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<__bit_shift_left<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(__bit_shift_left<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr< _BinaryOp<__bit_shift_left<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator<<(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<__bit_shift_left<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__bit_shift_left<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<__bit_shift_right<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator>>(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<__bit_shift_right<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(__bit_shift_right<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<
+ _BinaryOp<__bit_shift_right<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator>>(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<__bit_shift_right<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(__bit_shift_right<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr< _BinaryOp<__bit_shift_right<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator>>(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<__bit_shift_right<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__bit_shift_right<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<logical_and<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator&&(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<logical_and<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(logical_and<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<logical_and<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator&&(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<logical_and<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(logical_and<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<logical_and<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator&&(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<logical_and<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(logical_and<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<logical_or<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator||(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<logical_or<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(logical_or<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<logical_or<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator||(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<logical_or<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(logical_or<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<logical_or<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator||(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<logical_or<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(logical_or<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<equal_to<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator==(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<equal_to<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(equal_to<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<equal_to<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator==(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<equal_to<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(equal_to<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<equal_to<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator==(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<equal_to<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(equal_to<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<not_equal_to<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator!=(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<not_equal_to<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(not_equal_to<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<not_equal_to<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator!=(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<not_equal_to<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(not_equal_to<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<not_equal_to<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator!=(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<not_equal_to<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(not_equal_to<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<less<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator<(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<less<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(less<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<less<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator<(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<less<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(less<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<less<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator<(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<less<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(less<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<greater<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator>(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<greater<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(greater<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<greater<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator>(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<greater<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(greater<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<greater<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator>(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<greater<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(greater<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<less_equal<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator<=(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<less_equal<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(less_equal<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<less_equal<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator<=(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<less_equal<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(less_equal<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<less_equal<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator<=(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<less_equal<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(less_equal<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<greater_equal<typename _Expr1::value_type>, _Expr1, _Expr2> >
+operator>=(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<greater_equal<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(greater_equal<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<greater_equal<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+operator>=(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<greater_equal<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(greater_equal<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<greater_equal<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+operator>=(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<greater_equal<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(greater_equal<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__abs_expr<typename _Expr::value_type>, _Expr> >
+abs(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__abs_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__abs_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__acos_expr<typename _Expr::value_type>, _Expr> >
+acos(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__acos_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__acos_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__asin_expr<typename _Expr::value_type>, _Expr> >
+asin(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__asin_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__asin_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__atan_expr<typename _Expr::value_type>, _Expr> >
+atan(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__atan_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__atan_expr<value_type>(), __x));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<__atan2_expr<typename _Expr1::value_type>, _Expr1, _Expr2> >
+atan2(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<__atan2_expr<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(__atan2_expr<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<__atan2_expr<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+atan2(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<__atan2_expr<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(__atan2_expr<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<__atan2_expr<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+atan2(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<__atan2_expr<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__atan2_expr<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__cos_expr<typename _Expr::value_type>, _Expr> >
+cos(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__cos_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__cos_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__cosh_expr<typename _Expr::value_type>, _Expr> >
+cosh(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__cosh_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__cosh_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__exp_expr<typename _Expr::value_type>, _Expr> >
+exp(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__exp_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__exp_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__log_expr<typename _Expr::value_type>, _Expr> >
+log(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__log_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__log_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__log10_expr<typename _Expr::value_type>, _Expr> >
+log10(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__log10_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__log10_expr<value_type>(), __x));
+}
+
+template <class _Expr1,
+ class _Expr2,
+ __enable_if_t<__is_val_expr<_Expr1>::value && __is_val_expr<_Expr2>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_BinaryOp<__pow_expr<typename _Expr1::value_type>, _Expr1, _Expr2> >
+pow(const _Expr1& __x, const _Expr2& __y) {
+ typedef typename _Expr1::value_type value_type;
+ typedef _BinaryOp<__pow_expr<value_type>, _Expr1, _Expr2> _Op;
+ return __val_expr<_Op>(_Op(__pow_expr<value_type>(), __x, __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<__pow_expr<typename _Expr::value_type>, _Expr, __scalar_expr<typename _Expr::value_type> > >
+pow(const _Expr& __x, const typename _Expr::value_type& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<__pow_expr<value_type>, _Expr, __scalar_expr<value_type> > _Op;
+ return __val_expr<_Op>(_Op(__pow_expr<value_type>(), __x, __scalar_expr<value_type>(__y, __x.size())));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI
+__val_expr<_BinaryOp<__pow_expr<typename _Expr::value_type>, __scalar_expr<typename _Expr::value_type>, _Expr> >
+pow(const typename _Expr::value_type& __x, const _Expr& __y) {
+ typedef typename _Expr::value_type value_type;
+ typedef _BinaryOp<__pow_expr<value_type>, __scalar_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__pow_expr<value_type>(), __scalar_expr<value_type>(__x, __y.size()), __y));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__sin_expr<typename _Expr::value_type>, _Expr> >
+sin(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__sin_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__sin_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__sinh_expr<typename _Expr::value_type>, _Expr> >
+sinh(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__sinh_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__sinh_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__sqrt_expr<typename _Expr::value_type>, _Expr> >
+sqrt(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__sqrt_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__sqrt_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__tan_expr<typename _Expr::value_type>, _Expr> >
+tan(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__tan_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__tan_expr<value_type>(), __x));
+}
+
+template <class _Expr, __enable_if_t<__is_val_expr<_Expr>::value, int> = 0>
+inline _LIBCPP_HIDE_FROM_ABI __val_expr<_UnaryOp<__tanh_expr<typename _Expr::value_type>, _Expr> >
+tanh(const _Expr& __x) {
+ typedef typename _Expr::value_type value_type;
+ typedef _UnaryOp<__tanh_expr<value_type>, _Expr> _Op;
+ return __val_expr<_Op>(_Op(__tanh_expr<value_type>(), __x));
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _Tp* begin(valarray<_Tp>& __v) {
+ return __v.__begin_;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI const _Tp* begin(const valarray<_Tp>& __v) {
+ return __v.__begin_;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI _Tp* end(valarray<_Tp>& __v) {
+ return __v.__end_;
+}
+
+template <class _Tp>
+inline _LIBCPP_HIDE_FROM_ABI const _Tp* end(const valarray<_Tp>& __v) {
+ return __v.__end_;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <concepts>
+# include <cstdlib>
+# include <cstring>
+# include <functional>
+# include <stdexcept>
+# include <type_traits>
+#endif
+
+#endif // _LIBCPP_VALARRAY
diff --git a/libcxx/include/__cxx03/variant b/libcxx/include/__cxx03/variant
new file mode 100644
index 00000000000000..5f2d03b7227b8c
--- /dev/null
+++ b/libcxx/include/__cxx03/variant
@@ -0,0 +1,1650 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_VARIANT
+#define _LIBCPP_VARIANT
+
+/*
+ variant synopsis
+
+namespace std {
+
+ // 20.7.2, class template variant
+ template <class... Types>
+ class variant {
+ public:
+
+ // 20.7.2.1, constructors
+ constexpr variant() noexcept(see below);
+ constexpr variant(const variant&);
+ constexpr variant(variant&&) noexcept(see below);
+
+ template <class T> constexpr variant(T&&) noexcept(see below);
+
+ template <class T, class... Args>
+ constexpr explicit variant(in_place_type_t<T>, Args&&...);
+
+ template <class T, class U, class... Args>
+ constexpr explicit variant(
+ in_place_type_t<T>, initializer_list<U>, Args&&...);
+
+ template <size_t I, class... Args>
+ constexpr explicit variant(in_place_index_t<I>, Args&&...);
+
+ template <size_t I, class U, class... Args>
+ constexpr explicit variant(
+ in_place_index_t<I>, initializer_list<U>, Args&&...);
+
+ // 20.7.2.2, destructor
+ constexpr ~variant(); // constexpr since c++20
+
+ // 20.7.2.3, assignment
+ constexpr variant& operator=(const variant&);
+ constexpr variant& operator=(variant&&) noexcept(see below);
+
+ template <class T>
+ constexpr variant& operator=(T&&) noexcept(see below); // constexpr since c++20
+
+ // 20.7.2.4, modifiers
+ template <class T, class... Args>
+ constexpr T& emplace(Args&&...); // constexpr since c++20
+
+ template <class T, class U, class... Args>
+ constexpr T& emplace(initializer_list<U>, Args&&...); // constexpr since c++20
+
+ template <size_t I, class... Args>
+ constexpr variant_alternative_t<I, variant>& emplace(Args&&...); // constexpr since c++20
+
+ template <size_t I, class U, class... Args>
+ constexpr variant_alternative_t<I, variant>&
+ emplace(initializer_list<U>, Args&&...); // constexpr since c++20
+
+ // 20.7.2.5, value status
+ constexpr bool valueless_by_exception() const noexcept;
+ constexpr size_t index() const noexcept;
+
+ // 20.7.2.6, swap
+ void swap(variant&) noexcept(see below);
+
+ // [variant.visit], visitation
+ template<class Self, class Visitor>
+ constexpr decltype(auto) visit(this Self&&, Visitor&&); // Since C++26
+ template<class R, class Self, class Visitor>
+ constexpr R visit(this Self&&, Visitor&&); // Since C++26
+ };
+
+ // 20.7.3, variant helper classes
+ template <class T> struct variant_size; // undefined
+
+ template <class T>
+ inline constexpr size_t variant_size_v = variant_size<T>::value;
+
+ template <class T> struct variant_size<const T>;
+ template <class T> struct variant_size<volatile T>;
+ template <class T> struct variant_size<const volatile T>;
+
+ template <class... Types>
+ struct variant_size<variant<Types...>>;
+
+ template <size_t I, class T> struct variant_alternative; // undefined
+
+ template <size_t I, class T>
+ using variant_alternative_t = typename variant_alternative<I, T>::type;
+
+ template <size_t I, class T> struct variant_alternative<I, const T>;
+ template <size_t I, class T> struct variant_alternative<I, volatile T>;
+ template <size_t I, class T> struct variant_alternative<I, const volatile T>;
+
+ template <size_t I, class... Types>
+ struct variant_alternative<I, variant<Types...>>;
+
+ inline constexpr size_t variant_npos = -1;
+
+ // 20.7.4, value access
+ template <class T, class... Types>
+ constexpr bool holds_alternative(const variant<Types...>&) noexcept;
+
+ template <size_t I, class... Types>
+ constexpr variant_alternative_t<I, variant<Types...>>&
+ get(variant<Types...>&);
+
+ template <size_t I, class... Types>
+ constexpr variant_alternative_t<I, variant<Types...>>&&
+ get(variant<Types...>&&);
+
+ template <size_t I, class... Types>
+ constexpr variant_alternative_t<I, variant<Types...>> const&
+ get(const variant<Types...>&);
+
+ template <size_t I, class... Types>
+ constexpr variant_alternative_t<I, variant<Types...>> const&&
+ get(const variant<Types...>&&);
+
+ template <class T, class... Types>
+ constexpr T& get(variant<Types...>&);
+
+ template <class T, class... Types>
+ constexpr T&& get(variant<Types...>&&);
+
+ template <class T, class... Types>
+ constexpr const T& get(const variant<Types...>&);
+
+ template <class T, class... Types>
+ constexpr const T&& get(const variant<Types...>&&);
+
+ template <size_t I, class... Types>
+ constexpr add_pointer_t<variant_alternative_t<I, variant<Types...>>>
+ get_if(variant<Types...>*) noexcept;
+
+ template <size_t I, class... Types>
+ constexpr add_pointer_t<const variant_alternative_t<I, variant<Types...>>>
+ get_if(const variant<Types...>*) noexcept;
+
+ template <class T, class... Types>
+ constexpr add_pointer_t<T>
+ get_if(variant<Types...>*) noexcept;
+
+ template <class T, class... Types>
+ constexpr add_pointer_t<const T>
+ get_if(const variant<Types...>*) noexcept;
+
+ // 20.7.5, relational operators
+ template <class... Types>
+ constexpr bool operator==(const variant<Types...>&, const variant<Types...>&);
+
+ template <class... Types>
+ constexpr bool operator!=(const variant<Types...>&, const variant<Types...>&);
+
+ template <class... Types>
+ constexpr bool operator<(const variant<Types...>&, const variant<Types...>&);
+
+ template <class... Types>
+ constexpr bool operator>(const variant<Types...>&, const variant<Types...>&);
+
+ template <class... Types>
+ constexpr bool operator<=(const variant<Types...>&, const variant<Types...>&);
+
+ template <class... Types>
+ constexpr bool operator>=(const variant<Types...>&, const variant<Types...>&);
+
+ template <class... Types> requires (three_way_comparable<Types> && ...)
+ constexpr common_comparison_category_t<compare_three_way_result_t<Types>...>
+ operator<=>(const variant<Types...>&, const variant<Types...>&); // since C++20
+
+ // 20.7.6, visitation
+ template <class Visitor, class... Variants>
+ constexpr see below visit(Visitor&&, Variants&&...);
+
+ template <class R, class Visitor, class... Variants>
+ constexpr R visit(Visitor&&, Variants&&...); // since C++20
+
+ // 20.7.7, class monostate
+ struct monostate;
+
+ // 20.7.8, monostate relational operators
+ constexpr bool operator==(monostate, monostate) noexcept;
+ constexpr bool operator!=(monostate, monostate) noexcept; // until C++20
+ constexpr bool operator<(monostate, monostate) noexcept; // until C++20
+ constexpr bool operator>(monostate, monostate) noexcept; // until C++20
+ constexpr bool operator<=(monostate, monostate) noexcept; // until C++20
+ constexpr bool operator>=(monostate, monostate) noexcept; // until C++20
+ constexpr strong_ordering operator<=>(monostate, monostate) noexcept; // since C++20
+
+ // 20.7.9, specialized algorithms
+ template <class... Types>
+ void swap(variant<Types...>&, variant<Types...>&) noexcept(see below);
+
+ // 20.7.10, class bad_variant_access
+ class bad_variant_access;
+
+ // 20.7.11, hash support
+ template <class T> struct hash;
+ template <class... Types> struct hash<variant<Types...>>;
+ template <> struct hash<monostate>;
+
+} // namespace std
+
+*/
+
+#include <__compare/common_comparison_category.h>
+#include <__compare/compare_three_way_result.h>
+#include <__compare/three_way_comparable.h>
+#include <__config>
+#include <__exception/exception.h>
+#include <__functional/hash.h>
+#include <__functional/invoke.h>
+#include <__functional/operations.h>
+#include <__functional/unary_function.h>
+#include <__memory/addressof.h>
+#include <__memory/construct_at.h>
+#include <__tuple/find_index.h>
+#include <__tuple/sfinae_helpers.h>
+#include <__type_traits/add_const.h>
+#include <__type_traits/add_cv.h>
+#include <__type_traits/add_pointer.h>
+#include <__type_traits/add_volatile.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/dependent_type.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_destructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_reference.h>
+#include <__type_traits/is_trivially_assignable.h>
+#include <__type_traits/is_trivially_constructible.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <__type_traits/is_trivially_relocatable.h>
+#include <__type_traits/is_void.h>
+#include <__type_traits/remove_const.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/type_identity.h>
+#include <__type_traits/void_t.h>
+#include <__utility/declval.h>
+#include <__utility/forward.h>
+#include <__utility/forward_like.h>
+#include <__utility/in_place.h>
+#include <__utility/integer_sequence.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+#include <__variant/monostate.h>
+#include <__verbose_abort>
+#include <initializer_list>
+#include <limits>
+#include <new>
+#include <version>
+
+// standard-mandated includes
+
+// [variant.syn]
+#include <compare>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+namespace std { // explicitly not using versioning namespace
+
+class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS bad_variant_access : public exception {
+public:
+ const char* what() const _NOEXCEPT override;
+};
+
+} // namespace std
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+// Light N-dimensional array of function pointers. Used in place of std::array to avoid
+// adding a dependency.
+template <class _Tp, size_t _Size>
+struct __farray {
+ static_assert(_Size > 0, "N-dimensional array should never be empty in std::visit");
+ _Tp __buf_[_Size] = {};
+
+ _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& operator[](size_t __n) const noexcept { return __buf_[__n]; }
+};
+
+_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS void
+__throw_bad_variant_access() {
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ throw bad_variant_access();
+# else
+ _LIBCPP_VERBOSE_ABORT("bad_variant_access was thrown in -fno-exceptions mode");
+# endif
+}
+
+template <class... _Types>
+class _LIBCPP_TEMPLATE_VIS variant;
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS variant_size;
+
+template <class _Tp>
+inline constexpr size_t variant_size_v = variant_size<_Tp>::value;
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS variant_size<const _Tp> : variant_size<_Tp> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS variant_size<volatile _Tp> : variant_size<_Tp> {};
+
+template <class _Tp>
+struct _LIBCPP_TEMPLATE_VIS variant_size<const volatile _Tp> : variant_size<_Tp> {};
+
+template <class... _Types>
+struct _LIBCPP_TEMPLATE_VIS variant_size<variant<_Types...>> : integral_constant<size_t, sizeof...(_Types)> {};
+
+template <size_t _Ip, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS variant_alternative;
+
+template <size_t _Ip, class _Tp>
+using variant_alternative_t = typename variant_alternative<_Ip, _Tp>::type;
+
+template <size_t _Ip, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS variant_alternative<_Ip, const _Tp> : add_const<variant_alternative_t<_Ip, _Tp>> {};
+
+template <size_t _Ip, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS variant_alternative<_Ip, volatile _Tp> : add_volatile<variant_alternative_t<_Ip, _Tp>> {};
+
+template <size_t _Ip, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS variant_alternative<_Ip, const volatile _Tp> : add_cv<variant_alternative_t<_Ip, _Tp>> {};
+
+template <size_t _Ip, class... _Types>
+struct _LIBCPP_TEMPLATE_VIS variant_alternative<_Ip, variant<_Types...>> {
+ static_assert(_Ip < sizeof...(_Types), "Index out of bounds in std::variant_alternative<>");
+ using type = __type_pack_element<_Ip, _Types...>;
+};
+
+inline constexpr size_t variant_npos = static_cast<size_t>(-1);
+
+template <size_t _NumAlternatives>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __choose_index_type() {
+# ifdef _LIBCPP_ABI_VARIANT_INDEX_TYPE_OPTIMIZATION
+ if constexpr (_NumAlternatives < numeric_limits<unsigned char>::max())
+ return static_cast<unsigned char>(0);
+ else if constexpr (_NumAlternatives < numeric_limits<unsigned short>::max())
+ return static_cast<unsigned short>(0);
+ else
+# endif // _LIBCPP_ABI_VARIANT_INDEX_TYPE_OPTIMIZATION
+ return static_cast<unsigned int>(0);
+}
+
+template <size_t _NumAlts>
+using __variant_index_t = decltype(std::__choose_index_type<_NumAlts>());
+
+template <class _IndexType>
+constexpr _IndexType __variant_npos = static_cast<_IndexType>(-1);
+
+template <class... _Types>
+class _LIBCPP_TEMPLATE_VIS variant;
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr variant<_Types...>& __as_variant(variant<_Types...>& __vs) noexcept {
+ return __vs;
+}
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr const variant<_Types...>& __as_variant(const variant<_Types...>& __vs) noexcept {
+ return __vs;
+}
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr variant<_Types...>&& __as_variant(variant<_Types...>&& __vs) noexcept {
+ return std::move(__vs);
+}
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr const variant<_Types...>&& __as_variant(const variant<_Types...>&& __vs) noexcept {
+ return std::move(__vs);
+}
+
+namespace __find_detail {
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr size_t __find_index() {
+ constexpr bool __matches[] = {is_same_v<_Tp, _Types>...};
+ size_t __result = __not_found;
+ for (size_t __i = 0; __i < sizeof...(_Types); ++__i) {
+ if (__matches[__i]) {
+ if (__result != __not_found) {
+ return __ambiguous;
+ }
+ __result = __i;
+ }
+ }
+ return __result;
+}
+
+template <size_t _Index>
+struct __find_unambiguous_index_sfinae_impl : integral_constant<size_t, _Index> {};
+
+template <>
+struct __find_unambiguous_index_sfinae_impl<__not_found> {};
+
+template <>
+struct __find_unambiguous_index_sfinae_impl<__ambiguous> {};
+
+template <class _Tp, class... _Types>
+struct __find_unambiguous_index_sfinae : __find_unambiguous_index_sfinae_impl<__find_index<_Tp, _Types...>()> {};
+
+} // namespace __find_detail
+
+namespace __variant_detail {
+
+struct __valueless_t {};
+
+enum class _Trait { _TriviallyAvailable, _Available, _Unavailable };
+
+template <typename _Tp, template <typename> class _IsTriviallyAvailable, template <typename> class _IsAvailable>
+constexpr _Trait __trait =
+ _IsTriviallyAvailable<_Tp>::value ? _Trait::_TriviallyAvailable
+ : _IsAvailable<_Tp>::value
+ ? _Trait::_Available
+ : _Trait::_Unavailable;
+
+_LIBCPP_HIDE_FROM_ABI constexpr _Trait __common_trait(initializer_list<_Trait> __traits) {
+ _Trait __result = _Trait::_TriviallyAvailable;
+ for (_Trait __t : __traits) {
+ if (static_cast<int>(__t) > static_cast<int>(__result)) {
+ __result = __t;
+ }
+ }
+ return __result;
+}
+
+template <typename... _Types>
+struct __traits {
+ static constexpr _Trait __copy_constructible_trait =
+ __variant_detail::__common_trait({__trait<_Types, is_trivially_copy_constructible, is_copy_constructible>...});
+
+ static constexpr _Trait __move_constructible_trait =
+ __variant_detail::__common_trait({__trait<_Types, is_trivially_move_constructible, is_move_constructible>...});
+
+ static constexpr _Trait __copy_assignable_trait = __variant_detail::__common_trait(
+ {__copy_constructible_trait, __trait<_Types, is_trivially_copy_assignable, is_copy_assignable>...});
+
+ static constexpr _Trait __move_assignable_trait = __variant_detail::__common_trait(
+ {__move_constructible_trait, __trait<_Types, is_trivially_move_assignable, is_move_assignable>...});
+
+ static constexpr _Trait __destructible_trait =
+ __variant_detail::__common_trait({__trait<_Types, is_trivially_destructible, is_destructible>...});
+};
+
+namespace __access {
+
+struct __union {
+ template <class _Vp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto&& __get_alt(_Vp&& __v, in_place_index_t<0>) {
+ return std::forward<_Vp>(__v).__head;
+ }
+
+ template <class _Vp, size_t _Ip>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto&& __get_alt(_Vp&& __v, in_place_index_t<_Ip>) {
+ return __get_alt(std::forward<_Vp>(__v).__tail, in_place_index<_Ip - 1>);
+ }
+};
+
+struct __base {
+ template <size_t _Ip, class _Vp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto&& __get_alt(_Vp&& __v) {
+ return __union::__get_alt(std::forward<_Vp>(__v).__data, in_place_index<_Ip>);
+ }
+};
+
+struct __variant {
+ template <size_t _Ip, class _Vp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto&& __get_alt(_Vp&& __v) {
+ return __base::__get_alt<_Ip>(std::forward<_Vp>(__v).__impl_);
+ }
+};
+
+} // namespace __access
+
+namespace __visitation {
+
+struct __base {
+ template <class _Visitor, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto)
+ __visit_alt_at(size_t __index, _Visitor&& __visitor, _Vs&&... __vs) {
+ constexpr auto __fdiagonal = __make_fdiagonal<_Visitor&&, decltype(std::forward<_Vs>(__vs).__as_base())...>();
+ return __fdiagonal[__index](std::forward<_Visitor>(__visitor), std::forward<_Vs>(__vs).__as_base()...);
+ }
+
+ template <class _Visitor, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto) __visit_alt(_Visitor&& __visitor, _Vs&&... __vs) {
+ constexpr auto __fmatrix = __make_fmatrix<_Visitor&&, decltype(std::forward<_Vs>(__vs).__as_base())...>();
+ return __at(__fmatrix, __vs.index()...)(std::forward<_Visitor>(__visitor), std::forward<_Vs>(__vs).__as_base()...);
+ }
+
+private:
+ template <class _Tp>
+ _LIBCPP_HIDE_FROM_ABI static constexpr const _Tp& __at(const _Tp& __elem) {
+ return __elem;
+ }
+
+ template <class _Tp, size_t _Np, typename... _Indices>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto&&
+ __at(const __farray<_Tp, _Np>& __elems, size_t __index, _Indices... __indices) {
+ return __at(__elems[__index], __indices...);
+ }
+
+ template <class _Fp, class... _Fs>
+ static _LIBCPP_HIDE_FROM_ABI constexpr void __std_visit_visitor_return_type_check() {
+ static_assert(
+ __all<is_same_v<_Fp, _Fs>...>::value, "`std::visit` requires the visitor to have a single return type.");
+ }
+
+ template <class... _Fs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_farray(_Fs&&... __fs) {
+ __std_visit_visitor_return_type_check<__remove_cvref_t<_Fs>...>();
+ using __result = __farray<common_type_t<__remove_cvref_t<_Fs>...>, sizeof...(_Fs)>;
+ return __result{{std::forward<_Fs>(__fs)...}};
+ }
+
+ template <size_t... _Is>
+ struct __dispatcher {
+ template <class _Fp, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto) __dispatch(_Fp __f, _Vs... __vs) {
+ return std::__invoke(static_cast<_Fp>(__f), __access::__base::__get_alt<_Is>(static_cast<_Vs>(__vs))...);
+ }
+ };
+
+ template <class _Fp, class... _Vs, size_t... _Is>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_dispatch(index_sequence<_Is...>) {
+ return __dispatcher<_Is...>::template __dispatch<_Fp, _Vs...>;
+ }
+
+ template <size_t _Ip, class _Fp, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_fdiagonal_impl() {
+ return __make_dispatch<_Fp, _Vs...>(index_sequence<((void)__type_identity<_Vs>{}, _Ip)...>{});
+ }
+
+ template <class _Fp, class... _Vs, size_t... _Is>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_fdiagonal_impl(index_sequence<_Is...>) {
+ return __base::__make_farray(__make_fdiagonal_impl<_Is, _Fp, _Vs...>()...);
+ }
+
+ template <class _Fp, class _Vp, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_fdiagonal() {
+ constexpr size_t __np = __remove_cvref_t<_Vp>::__size();
+ static_assert(__all<(__np == __remove_cvref_t<_Vs>::__size())...>::value);
+ return __make_fdiagonal_impl<_Fp, _Vp, _Vs...>(make_index_sequence<__np>{});
+ }
+
+ template <class _Fp, class... _Vs, size_t... _Is>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_fmatrix_impl(index_sequence<_Is...> __is) {
+ return __make_dispatch<_Fp, _Vs...>(__is);
+ }
+
+ template <class _Fp, class... _Vs, size_t... _Is, size_t... _Js, class... _Ls>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto
+ __make_fmatrix_impl(index_sequence<_Is...>, index_sequence<_Js...>, _Ls... __ls) {
+ return __base::__make_farray(__make_fmatrix_impl<_Fp, _Vs...>(index_sequence<_Is..., _Js>{}, __ls...)...);
+ }
+
+ template <class _Fp, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_fmatrix() {
+ return __make_fmatrix_impl<_Fp, _Vs...>(
+ index_sequence<>{}, make_index_sequence<__remove_cvref_t<_Vs>::__size()>{}...);
+ }
+};
+
+struct __variant {
+ template <class _Visitor, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto)
+ __visit_alt_at(size_t __index, _Visitor&& __visitor, _Vs&&... __vs) {
+ return __base::__visit_alt_at(__index, std::forward<_Visitor>(__visitor), std::forward<_Vs>(__vs).__impl_...);
+ }
+
+ template <class _Visitor, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto) __visit_alt(_Visitor&& __visitor, _Vs&&... __vs) {
+ return __base::__visit_alt(
+ std::forward<_Visitor>(__visitor), std::__as_variant(std::forward<_Vs>(__vs)).__impl_...);
+ }
+
+ template <class _Visitor, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto)
+ __visit_value_at(size_t __index, _Visitor&& __visitor, _Vs&&... __vs) {
+ return __visit_alt_at(__index, __make_value_visitor(std::forward<_Visitor>(__visitor)), std::forward<_Vs>(__vs)...);
+ }
+
+ template <class _Visitor, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto) __visit_value(_Visitor&& __visitor, _Vs&&... __vs) {
+ return __visit_alt(__make_value_visitor(std::forward<_Visitor>(__visitor)), std::forward<_Vs>(__vs)...);
+ }
+
+# if _LIBCPP_STD_VER >= 20
+ template <class _Rp, class _Visitor, class... _Vs>
+ _LIBCPP_HIDE_FROM_ABI static constexpr _Rp __visit_value(_Visitor&& __visitor, _Vs&&... __vs) {
+ return __visit_alt(__make_value_visitor<_Rp>(std::forward<_Visitor>(__visitor)), std::forward<_Vs>(__vs)...);
+ }
+# endif
+
+private:
+ template <class _Visitor, class... _Values>
+ static _LIBCPP_HIDE_FROM_ABI constexpr void __std_visit_exhaustive_visitor_check() {
+ static_assert(is_invocable_v<_Visitor, _Values...>, "`std::visit` requires the visitor to be exhaustive.");
+ }
+
+ template <class _Visitor>
+ struct __value_visitor {
+ template <class... _Alts>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator()(_Alts&&... __alts) const {
+ __std_visit_exhaustive_visitor_check< _Visitor, decltype((std::forward<_Alts>(__alts).__value))...>();
+ return std::__invoke(std::forward<_Visitor>(__visitor), std::forward<_Alts>(__alts).__value...);
+ }
+ _Visitor&& __visitor;
+ };
+
+# if _LIBCPP_STD_VER >= 20
+ template <class _Rp, class _Visitor>
+ struct __value_visitor_return_type {
+ template <class... _Alts>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Rp operator()(_Alts&&... __alts) const {
+ __std_visit_exhaustive_visitor_check< _Visitor, decltype((std::forward<_Alts>(__alts).__value))...>();
+ if constexpr (is_void_v<_Rp>) {
+ std::__invoke(std::forward<_Visitor>(__visitor), std::forward<_Alts>(__alts).__value...);
+ } else {
+ return std::__invoke(std::forward<_Visitor>(__visitor), std::forward<_Alts>(__alts).__value...);
+ }
+ }
+
+ _Visitor&& __visitor;
+ };
+# endif
+
+ template <class _Visitor>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_value_visitor(_Visitor&& __visitor) {
+ return __value_visitor<_Visitor>{std::forward<_Visitor>(__visitor)};
+ }
+
+# if _LIBCPP_STD_VER >= 20
+ template <class _Rp, class _Visitor>
+ _LIBCPP_HIDE_FROM_ABI static constexpr auto __make_value_visitor(_Visitor&& __visitor) {
+ return __value_visitor_return_type<_Rp, _Visitor>{std::forward<_Visitor>(__visitor)};
+ }
+# endif
+};
+
+} // namespace __visitation
+
+// Adding semi-colons in macro expansions helps clang-format to do a better job.
+// This macro is used to avoid compilation errors due to "stray" semi-colons.
+# define _LIBCPP_EAT_SEMICOLON static_assert(true, "")
+
+template <size_t _Index, class _Tp>
+struct _LIBCPP_TEMPLATE_VIS __alt {
+ using __value_type = _Tp;
+ static constexpr size_t __index = _Index;
+
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr __alt(in_place_t, _Args&&... __args)
+ : __value(std::forward<_Args>(__args)...) {}
+
+ __value_type __value;
+};
+
+template <_Trait _DestructibleTrait, size_t _Index, class... _Types>
+union _LIBCPP_TEMPLATE_VIS __union;
+
+template <_Trait _DestructibleTrait, size_t _Index>
+union _LIBCPP_TEMPLATE_VIS __union<_DestructibleTrait, _Index> {};
+
+# define _LIBCPP_VARIANT_UNION(destructible_trait, destructor_definition) \
+ template <size_t _Index, class _Tp, class... _Types> \
+ union _LIBCPP_TEMPLATE_VIS __union<destructible_trait, _Index, _Tp, _Types...> { \
+ public: \
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr __union(__valueless_t) noexcept : __dummy{} {} \
+ \
+ template <class... _Args> \
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr __union(in_place_index_t<0>, _Args&&... __args) \
+ : __head(in_place, std::forward<_Args>(__args)...) {} \
+ \
+ template <size_t _Ip, class... _Args> \
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr __union(in_place_index_t<_Ip>, _Args&&... __args) \
+ : __tail(in_place_index<_Ip - 1>, std::forward<_Args>(__args)...) {} \
+ \
+ _LIBCPP_HIDE_FROM_ABI __union(const __union&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __union(__union&&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __union& operator=(const __union&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __union& operator=(__union&&) = default; \
+ destructor_definition; \
+ \
+ private: \
+ char __dummy; \
+ __alt<_Index, _Tp> __head; \
+ __union<destructible_trait, _Index + 1, _Types...> __tail; \
+ \
+ friend struct __access::__union; \
+ }
+
+_LIBCPP_VARIANT_UNION(_Trait::_TriviallyAvailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__union() = default);
+_LIBCPP_VARIANT_UNION(
+ _Trait::_Available, _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__union() {} _LIBCPP_EAT_SEMICOLON);
+_LIBCPP_VARIANT_UNION(_Trait::_Unavailable, _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__union() = delete);
+
+# undef _LIBCPP_VARIANT_UNION
+
+template <_Trait _DestructibleTrait, class... _Types>
+class _LIBCPP_TEMPLATE_VIS __base {
+public:
+ using __index_t = __variant_index_t<sizeof...(_Types)>;
+
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr __base(__valueless_t __tag) noexcept
+ : __data(__tag), __index(__variant_npos<__index_t>) {}
+
+ template <size_t _Ip, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr __base(in_place_index_t<_Ip>, _Args&&... __args)
+ : __data(in_place_index<_Ip>, std::forward<_Args>(__args)...), __index(_Ip) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool valueless_by_exception() const noexcept { return index() == variant_npos; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr size_t index() const noexcept {
+ return __index == __variant_npos<__index_t> ? variant_npos : __index;
+ }
+
+protected:
+ _LIBCPP_HIDE_FROM_ABI constexpr auto&& __as_base() & { return *this; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto&& __as_base() && { return std::move(*this); }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto&& __as_base() const& { return *this; }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr auto&& __as_base() const&& { return std::move(*this); }
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr size_t __size() { return sizeof...(_Types); }
+
+ __union<_DestructibleTrait, 0, _Types...> __data;
+ __index_t __index;
+
+ friend struct __access::__base;
+ friend struct __visitation::__base;
+};
+
+template <class _Traits, _Trait = _Traits::__destructible_trait>
+class _LIBCPP_TEMPLATE_VIS __dtor;
+
+# define _LIBCPP_VARIANT_DESTRUCTOR(destructible_trait, destructor_definition, destroy) \
+ template <class... _Types> \
+ class _LIBCPP_TEMPLATE_VIS __dtor<__traits<_Types...>, destructible_trait> \
+ : public __base<destructible_trait, _Types...> { \
+ using __base_type = __base<destructible_trait, _Types...>; \
+ using __index_t = typename __base_type::__index_t; \
+ \
+ public: \
+ using __base_type::__base_type; \
+ using __base_type::operator=; \
+ _LIBCPP_HIDE_FROM_ABI __dtor(const __dtor&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __dtor(__dtor&&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __dtor& operator=(const __dtor&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __dtor& operator=(__dtor&&) = default; \
+ destructor_definition; \
+ \
+ protected: \
+ destroy; \
+ }
+
+_LIBCPP_VARIANT_DESTRUCTOR(
+ _Trait::_TriviallyAvailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__dtor() = default,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __destroy() noexcept {
+ this->__index = __variant_npos<__index_t>;
+ } _LIBCPP_EAT_SEMICOLON);
+
+_LIBCPP_VARIANT_DESTRUCTOR(
+ _Trait::_Available,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__dtor() { __destroy(); } _LIBCPP_EAT_SEMICOLON,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __destroy() noexcept {
+ if (!this->valueless_by_exception()) {
+ __visitation::__base::__visit_alt(
+ [](auto& __alt) noexcept {
+ using __alt_type = __remove_cvref_t<decltype(__alt)>;
+ __alt.~__alt_type();
+ },
+ *this);
+ }
+ this->__index = __variant_npos<__index_t>;
+ } _LIBCPP_EAT_SEMICOLON);
+
+_LIBCPP_VARIANT_DESTRUCTOR(_Trait::_Unavailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__dtor() = delete,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __destroy() noexcept = delete);
+
+# undef _LIBCPP_VARIANT_DESTRUCTOR
+
+template <class _Traits>
+class _LIBCPP_TEMPLATE_VIS __ctor : public __dtor<_Traits> {
+ using __base_type = __dtor<_Traits>;
+
+public:
+ using __base_type::__base_type;
+ using __base_type::operator=;
+
+protected:
+ template <class _Rhs>
+ _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX20 void __generic_construct(__ctor& __lhs, _Rhs&& __rhs) {
+ __lhs.__destroy();
+ if (!__rhs.valueless_by_exception()) {
+ auto __rhs_index = __rhs.index();
+ __visitation::__base::__visit_alt_at(
+ __rhs_index,
+ [&__lhs](auto&& __rhs_alt) {
+ std::__construct_at(std::addressof(__lhs.__data),
+ in_place_index<__decay_t<decltype(__rhs_alt)>::__index>,
+ std::forward<decltype(__rhs_alt)>(__rhs_alt).__value);
+ },
+ std::forward<_Rhs>(__rhs));
+ __lhs.__index = __rhs_index;
+ }
+ }
+};
+
+template <class _Traits, _Trait = _Traits::__move_constructible_trait>
+class _LIBCPP_TEMPLATE_VIS __move_constructor;
+
+# define _LIBCPP_VARIANT_MOVE_CONSTRUCTOR(move_constructible_trait, move_constructor_definition) \
+ template <class... _Types> \
+ class _LIBCPP_TEMPLATE_VIS __move_constructor<__traits<_Types...>, move_constructible_trait> \
+ : public __ctor<__traits<_Types...>> { \
+ using __base_type = __ctor<__traits<_Types...>>; \
+ \
+ public: \
+ using __base_type::__base_type; \
+ using __base_type::operator=; \
+ \
+ _LIBCPP_HIDE_FROM_ABI __move_constructor(const __move_constructor&) = default; \
+ _LIBCPP_HIDE_FROM_ABI ~__move_constructor() = default; \
+ _LIBCPP_HIDE_FROM_ABI __move_constructor& operator=(const __move_constructor&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __move_constructor& operator=(__move_constructor&&) = default; \
+ move_constructor_definition; \
+ }
+
+_LIBCPP_VARIANT_MOVE_CONSTRUCTOR(
+ _Trait::_TriviallyAvailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __move_constructor(__move_constructor&& __that) = default);
+
+_LIBCPP_VARIANT_MOVE_CONSTRUCTOR(
+ _Trait::_Available,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __move_constructor(__move_constructor&& __that) noexcept(
+ __all<is_nothrow_move_constructible_v<_Types>...>::value)
+ : __move_constructor(__valueless_t{}) {
+ this->__generic_construct(*this, std::move(__that));
+ } _LIBCPP_EAT_SEMICOLON);
+
+_LIBCPP_VARIANT_MOVE_CONSTRUCTOR(
+ _Trait::_Unavailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __move_constructor(__move_constructor&&) = delete);
+
+# undef _LIBCPP_VARIANT_MOVE_CONSTRUCTOR
+
+template <class _Traits, _Trait = _Traits::__copy_constructible_trait>
+class _LIBCPP_TEMPLATE_VIS __copy_constructor;
+
+# define _LIBCPP_VARIANT_COPY_CONSTRUCTOR(copy_constructible_trait, copy_constructor_definition) \
+ template <class... _Types> \
+ class _LIBCPP_TEMPLATE_VIS __copy_constructor<__traits<_Types...>, copy_constructible_trait> \
+ : public __move_constructor<__traits<_Types...>> { \
+ using __base_type = __move_constructor<__traits<_Types...>>; \
+ \
+ public: \
+ using __base_type::__base_type; \
+ using __base_type::operator=; \
+ \
+ _LIBCPP_HIDE_FROM_ABI __copy_constructor(__copy_constructor&&) = default; \
+ _LIBCPP_HIDE_FROM_ABI ~__copy_constructor() = default; \
+ _LIBCPP_HIDE_FROM_ABI __copy_constructor& operator=(const __copy_constructor&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __copy_constructor& operator=(__copy_constructor&&) = default; \
+ copy_constructor_definition; \
+ }
+
+_LIBCPP_VARIANT_COPY_CONSTRUCTOR(
+ _Trait::_TriviallyAvailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __copy_constructor(const __copy_constructor& __that) = default);
+
+_LIBCPP_VARIANT_COPY_CONSTRUCTOR(
+ _Trait::_Available,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __copy_constructor(const __copy_constructor& __that)
+ : __copy_constructor(__valueless_t{}) { this->__generic_construct(*this, __that); } _LIBCPP_EAT_SEMICOLON);
+
+_LIBCPP_VARIANT_COPY_CONSTRUCTOR(
+ _Trait::_Unavailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __copy_constructor(const __copy_constructor&) = delete);
+
+# undef _LIBCPP_VARIANT_COPY_CONSTRUCTOR
+
+template <class _Traits>
+class _LIBCPP_TEMPLATE_VIS __assignment : public __copy_constructor<_Traits> {
+ using __base_type = __copy_constructor<_Traits>;
+
+public:
+ using __base_type::__base_type;
+ using __base_type::operator=;
+
+ template <size_t _Ip, class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 auto& __emplace(_Args&&... __args) {
+ this->__destroy();
+ std::__construct_at(std::addressof(this->__data), in_place_index<_Ip>, std::forward<_Args>(__args)...);
+ this->__index = _Ip;
+ return __access::__base::__get_alt<_Ip>(*this).__value;
+ }
+
+protected:
+ template <size_t _Ip, class _Tp, class _Arg>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __assign_alt(__alt<_Ip, _Tp>& __a, _Arg&& __arg) {
+ if (this->index() == _Ip) {
+ __a.__value = std::forward<_Arg>(__arg);
+ } else {
+ struct {
+ _LIBCPP_HIDDEN _LIBCPP_CONSTEXPR_SINCE_CXX20 void operator()(true_type) const {
+ __this->__emplace<_Ip>(std::forward<_Arg>(__arg));
+ }
+ _LIBCPP_HIDDEN _LIBCPP_CONSTEXPR_SINCE_CXX20 void operator()(false_type) const {
+ __this->__emplace<_Ip>(_Tp(std::forward<_Arg>(__arg)));
+ }
+ __assignment* __this;
+ _Arg&& __arg;
+ } __impl{this, std::forward<_Arg>(__arg)};
+ __impl(bool_constant < is_nothrow_constructible_v<_Tp, _Arg> || !is_nothrow_move_constructible_v < _Tp >> {});
+ }
+ }
+
+ template <class _That>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __generic_assign(_That&& __that) {
+ if (this->valueless_by_exception() && __that.valueless_by_exception()) {
+ // do nothing.
+ } else if (__that.valueless_by_exception()) {
+ this->__destroy();
+ } else {
+ __visitation::__base::__visit_alt_at(
+ __that.index(),
+ [this](auto& __this_alt, auto&& __that_alt) {
+ this->__assign_alt(__this_alt, std::forward<decltype(__that_alt)>(__that_alt).__value);
+ },
+ *this,
+ std::forward<_That>(__that));
+ }
+ }
+};
+
+template <class _Traits, _Trait = _Traits::__move_assignable_trait>
+class _LIBCPP_TEMPLATE_VIS __move_assignment;
+
+# define _LIBCPP_VARIANT_MOVE_ASSIGNMENT(move_assignable_trait, move_assignment_definition) \
+ template <class... _Types> \
+ class _LIBCPP_TEMPLATE_VIS __move_assignment<__traits<_Types...>, move_assignable_trait> \
+ : public __assignment<__traits<_Types...>> { \
+ using __base_type = __assignment<__traits<_Types...>>; \
+ \
+ public: \
+ using __base_type::__base_type; \
+ using __base_type::operator=; \
+ \
+ _LIBCPP_HIDE_FROM_ABI __move_assignment(const __move_assignment&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __move_assignment(__move_assignment&&) = default; \
+ _LIBCPP_HIDE_FROM_ABI ~__move_assignment() = default; \
+ _LIBCPP_HIDE_FROM_ABI __move_assignment& operator=(const __move_assignment&) = default; \
+ move_assignment_definition; \
+ }
+
+_LIBCPP_VARIANT_MOVE_ASSIGNMENT(_Trait::_TriviallyAvailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __move_assignment& operator=(
+ __move_assignment&& __that) = default);
+
+_LIBCPP_VARIANT_MOVE_ASSIGNMENT(
+ _Trait::_Available,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __move_assignment&
+ operator=(__move_assignment&& __that) noexcept(
+ __all<(is_nothrow_move_constructible_v<_Types> && is_nothrow_move_assignable_v<_Types>)...>::value) {
+ this->__generic_assign(std::move(__that));
+ return *this;
+ } _LIBCPP_EAT_SEMICOLON);
+
+_LIBCPP_VARIANT_MOVE_ASSIGNMENT(
+ _Trait::_Unavailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __move_assignment& operator=(__move_assignment&&) = delete);
+
+# undef _LIBCPP_VARIANT_MOVE_ASSIGNMENT
+
+template <class _Traits, _Trait = _Traits::__copy_assignable_trait>
+class _LIBCPP_TEMPLATE_VIS __copy_assignment;
+
+# define _LIBCPP_VARIANT_COPY_ASSIGNMENT(copy_assignable_trait, copy_assignment_definition) \
+ template <class... _Types> \
+ class _LIBCPP_TEMPLATE_VIS __copy_assignment<__traits<_Types...>, copy_assignable_trait> \
+ : public __move_assignment<__traits<_Types...>> { \
+ using __base_type = __move_assignment<__traits<_Types...>>; \
+ \
+ public: \
+ using __base_type::__base_type; \
+ using __base_type::operator=; \
+ \
+ _LIBCPP_HIDE_FROM_ABI __copy_assignment(const __copy_assignment&) = default; \
+ _LIBCPP_HIDE_FROM_ABI __copy_assignment(__copy_assignment&&) = default; \
+ _LIBCPP_HIDE_FROM_ABI ~__copy_assignment() = default; \
+ _LIBCPP_HIDE_FROM_ABI __copy_assignment& operator=(__copy_assignment&&) = default; \
+ copy_assignment_definition; \
+ }
+
+_LIBCPP_VARIANT_COPY_ASSIGNMENT(_Trait::_TriviallyAvailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __copy_assignment& operator=(
+ const __copy_assignment& __that) = default);
+
+_LIBCPP_VARIANT_COPY_ASSIGNMENT(
+ _Trait::_Available,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __copy_assignment&
+ operator=(const __copy_assignment& __that) {
+ this->__generic_assign(__that);
+ return *this;
+ } _LIBCPP_EAT_SEMICOLON);
+
+_LIBCPP_VARIANT_COPY_ASSIGNMENT(_Trait::_Unavailable,
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __copy_assignment& operator=(
+ const __copy_assignment&) = delete);
+
+# undef _LIBCPP_VARIANT_COPY_ASSIGNMENT
+
+template <class... _Types>
+class _LIBCPP_TEMPLATE_VIS __impl : public __copy_assignment<__traits<_Types...>> {
+ using __base_type = __copy_assignment<__traits<_Types...>>;
+
+public:
+ using __base_type::__base_type; // get in_place_index_t constructor & friends
+ _LIBCPP_HIDE_FROM_ABI __impl(__impl const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __impl(__impl&&) = default;
+ _LIBCPP_HIDE_FROM_ABI __impl& operator=(__impl const&) = default;
+ _LIBCPP_HIDE_FROM_ABI __impl& operator=(__impl&&) = default;
+
+ template <size_t _Ip, class _Arg>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __assign(_Arg&& __arg) {
+ this->__assign_alt(__access::__base::__get_alt<_Ip>(*this), std::forward<_Arg>(__arg));
+ }
+
+ inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __swap(__impl& __that) {
+ if (this->valueless_by_exception() && __that.valueless_by_exception()) {
+ // do nothing.
+ } else if (this->index() == __that.index()) {
+ __visitation::__base::__visit_alt_at(
+ this->index(),
+ [](auto& __this_alt, auto& __that_alt) {
+ using std::swap;
+ swap(__this_alt.__value, __that_alt.__value);
+ },
+ *this,
+ __that);
+ } else {
+ __impl* __lhs = this;
+ __impl* __rhs = std::addressof(__that);
+ if (__lhs->__move_nothrow() && !__rhs->__move_nothrow()) {
+ std::swap(__lhs, __rhs);
+ }
+ __impl __tmp(std::move(*__rhs));
+# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ if constexpr (__all<is_nothrow_move_constructible_v<_Types>...>::value) {
+ this->__generic_construct(*__rhs, std::move(*__lhs));
+ } else {
+ // EXTENSION: When the move construction of `__lhs` into `__rhs` throws
+ // and `__tmp` is nothrow move constructible then we move `__tmp` back
+ // into `__rhs` and provide the strong exception safety guarantee.
+ try {
+ this->__generic_construct(*__rhs, std::move(*__lhs));
+ } catch (...) {
+ if (__tmp.__move_nothrow()) {
+ this->__generic_construct(*__rhs, std::move(__tmp));
+ }
+ throw;
+ }
+ }
+# else
+ // this isn't consolidated with the `if constexpr` branch above due to
+ // `throw` being ill-formed with exceptions disabled even when discarded.
+ this->__generic_construct(*__rhs, std::move(*__lhs));
+# endif
+ this->__generic_construct(*__lhs, std::move(__tmp));
+ }
+ }
+
+private:
+ constexpr inline _LIBCPP_HIDE_FROM_ABI bool __move_nothrow() const {
+ constexpr bool __results[] = {is_nothrow_move_constructible_v<_Types>...};
+ return this->valueless_by_exception() || __results[this->index()];
+ }
+};
+
+struct __no_narrowing_check {
+ template <class _Dest, class _Source>
+ using _Apply = __type_identity<_Dest>;
+};
+
+struct __narrowing_check {
+ template <class _Dest>
+ static auto __test_impl(_Dest (&&)[1]) -> __type_identity<_Dest>;
+ template <class _Dest, class _Source>
+ using _Apply _LIBCPP_NODEBUG = decltype(__test_impl<_Dest>({std::declval<_Source>()}));
+};
+
+template <class _Dest, class _Source>
+using __check_for_narrowing _LIBCPP_NODEBUG =
+ typename _If< is_arithmetic<_Dest>::value, __narrowing_check, __no_narrowing_check >::template _Apply<_Dest,
+ _Source>;
+
+template <class _Tp, size_t _Idx>
+struct __overload {
+ template <class _Up>
+ auto operator()(_Tp, _Up&&) const -> __check_for_narrowing<_Tp, _Up>;
+};
+
+template <class... _Bases>
+struct __all_overloads : _Bases... {
+ void operator()() const;
+ using _Bases::operator()...;
+};
+
+template <class _IdxSeq>
+struct __make_overloads_imp;
+
+template <size_t... _Idx>
+struct __make_overloads_imp<__tuple_indices<_Idx...> > {
+ template <class... _Types>
+ using _Apply _LIBCPP_NODEBUG = __all_overloads<__overload<_Types, _Idx>...>;
+};
+
+template <class... _Types>
+using _MakeOverloads _LIBCPP_NODEBUG =
+ typename __make_overloads_imp< __make_indices_imp<sizeof...(_Types), 0> >::template _Apply<_Types...>;
+
+template <class _Tp, class... _Types>
+using __best_match_t = typename invoke_result_t<_MakeOverloads<_Types...>, _Tp, _Tp>::type;
+
+} // namespace __variant_detail
+
+template <class _Visitor, class... _Vs, typename = void_t<decltype(std::__as_variant(std::declval<_Vs>()))...>>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr decltype(auto)
+visit(_Visitor&& __visitor, _Vs&&... __vs);
+
+# if _LIBCPP_STD_VER >= 20
+template <class _Rp,
+ class _Visitor,
+ class... _Vs,
+ typename = void_t<decltype(std::__as_variant(std::declval<_Vs>()))...>>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr _Rp
+visit(_Visitor&& __visitor, _Vs&&... __vs);
+# endif
+
+template <class... _Types>
+class _LIBCPP_TEMPLATE_VIS _LIBCPP_DECLSPEC_EMPTY_BASES variant
+ : private __sfinae_ctor_base< __all<is_copy_constructible_v<_Types>...>::value,
+ __all<is_move_constructible_v<_Types>...>::value>,
+ private __sfinae_assign_base<
+ __all<(is_copy_constructible_v<_Types> && is_copy_assignable_v<_Types>)...>::value,
+ __all<(is_move_constructible_v<_Types> && is_move_assignable_v<_Types>)...>::value> {
+ static_assert(0 < sizeof...(_Types), "variant must consist of at least one alternative.");
+
+ static_assert(__all<!is_array_v<_Types>...>::value, "variant can not have an array type as an alternative.");
+
+ static_assert(__all<!is_reference_v<_Types>...>::value, "variant can not have a reference type as an alternative.");
+
+ static_assert(__all<!is_void_v<_Types>...>::value, "variant can not have a void type as an alternative.");
+
+ using __first_type = variant_alternative_t<0, variant>;
+
+public:
+ using __trivially_relocatable =
+ conditional_t<_And<__libcpp_is_trivially_relocatable<_Types>...>::value, variant, void>;
+
+ template <bool _Dummy = true,
+ enable_if_t<__dependent_type<is_default_constructible<__first_type>, _Dummy>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr variant() noexcept(is_nothrow_default_constructible_v<__first_type>)
+ : __impl_(in_place_index<0>) {}
+
+ _LIBCPP_HIDE_FROM_ABI constexpr variant(const variant&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr variant(variant&&) = default;
+
+ template < class _Arg,
+ enable_if_t<!is_same_v<__remove_cvref_t<_Arg>, variant>, int> = 0,
+ enable_if_t<!__is_inplace_type<__remove_cvref_t<_Arg>>::value, int> = 0,
+ enable_if_t<!__is_inplace_index<__remove_cvref_t<_Arg>>::value, int> = 0,
+ class _Tp = __variant_detail::__best_match_t<_Arg, _Types...>,
+ size_t _Ip = __find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
+ enable_if_t<is_constructible_v<_Tp, _Arg>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI constexpr variant(_Arg&& __arg) noexcept(is_nothrow_constructible_v<_Tp, _Arg>)
+ : __impl_(in_place_index<_Ip>, std::forward<_Arg>(__arg)) {}
+
+ template <size_t _Ip,
+ class... _Args,
+ class = enable_if_t<(_Ip < sizeof...(_Types)), int>,
+ class _Tp = variant_alternative_t<_Ip, variant<_Types...>>,
+ enable_if_t<is_constructible_v<_Tp, _Args...>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr variant(in_place_index_t<_Ip>, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Tp, _Args...>)
+ : __impl_(in_place_index<_Ip>, std::forward<_Args>(__args)...) {}
+
+ template < size_t _Ip,
+ class _Up,
+ class... _Args,
+ enable_if_t<(_Ip < sizeof...(_Types)), int> = 0,
+ class _Tp = variant_alternative_t<_Ip, variant<_Types...>>,
+ enable_if_t<is_constructible_v<_Tp, initializer_list<_Up>&, _Args...>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr variant(
+ in_place_index_t<_Ip>,
+ initializer_list<_Up> __il,
+ _Args&&... __args) noexcept(is_nothrow_constructible_v<_Tp, initializer_list<_Up>&, _Args...>)
+ : __impl_(in_place_index<_Ip>, __il, std::forward<_Args>(__args)...) {}
+
+ template < class _Tp,
+ class... _Args,
+ size_t _Ip = __find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
+ enable_if_t<is_constructible_v<_Tp, _Args...>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr variant(in_place_type_t<_Tp>, _Args&&... __args) noexcept(
+ is_nothrow_constructible_v<_Tp, _Args...>)
+ : __impl_(in_place_index<_Ip>, std::forward<_Args>(__args)...) {}
+
+ template < class _Tp,
+ class _Up,
+ class... _Args,
+ size_t _Ip = __find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
+ enable_if_t<is_constructible_v<_Tp, initializer_list<_Up>&, _Args...>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr variant(
+ in_place_type_t<_Tp>,
+ initializer_list<_Up> __il,
+ _Args&&... __args) noexcept(is_nothrow_constructible_v<_Tp, initializer_list< _Up>&, _Args...>)
+ : __impl_(in_place_index<_Ip>, __il, std::forward<_Args>(__args)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~variant() = default;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr variant& operator=(const variant&) = default;
+ _LIBCPP_HIDE_FROM_ABI constexpr variant& operator=(variant&&) = default;
+
+ template < class _Arg,
+ enable_if_t<!is_same_v<__remove_cvref_t<_Arg>, variant>, int> = 0,
+ class _Tp = __variant_detail::__best_match_t<_Arg, _Types...>,
+ size_t _Ip = __find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
+ enable_if_t<is_assignable_v<_Tp&, _Arg> && is_constructible_v<_Tp, _Arg>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 variant&
+ operator=(_Arg&& __arg) noexcept(is_nothrow_assignable_v<_Tp&, _Arg> && is_nothrow_constructible_v<_Tp, _Arg>) {
+ __impl_.template __assign<_Ip>(std::forward<_Arg>(__arg));
+ return *this;
+ }
+
+ template < size_t _Ip,
+ class... _Args,
+ enable_if_t<(_Ip < sizeof...(_Types)), int> = 0,
+ class _Tp = variant_alternative_t<_Ip, variant<_Types...>>,
+ enable_if_t<is_constructible_v<_Tp, _Args...>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& emplace(_Args&&... __args) {
+ return __impl_.template __emplace<_Ip>(std::forward<_Args>(__args)...);
+ }
+
+ template < size_t _Ip,
+ class _Up,
+ class... _Args,
+ enable_if_t<(_Ip < sizeof...(_Types)), int> = 0,
+ class _Tp = variant_alternative_t<_Ip, variant<_Types...>>,
+ enable_if_t<is_constructible_v<_Tp, initializer_list<_Up>&, _Args...>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& emplace(initializer_list<_Up> __il, _Args&&... __args) {
+ return __impl_.template __emplace<_Ip>(__il, std::forward<_Args>(__args)...);
+ }
+
+ template < class _Tp,
+ class... _Args,
+ size_t _Ip = __find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
+ enable_if_t<is_constructible_v<_Tp, _Args...>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& emplace(_Args&&... __args) {
+ return __impl_.template __emplace<_Ip>(std::forward<_Args>(__args)...);
+ }
+
+ template < class _Tp,
+ class _Up,
+ class... _Args,
+ size_t _Ip = __find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
+ enable_if_t<is_constructible_v<_Tp, initializer_list<_Up>&, _Args...>, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& emplace(initializer_list<_Up> __il, _Args&&... __args) {
+ return __impl_.template __emplace<_Ip>(__il, std::forward<_Args>(__args)...);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr bool valueless_by_exception() const noexcept {
+ return __impl_.valueless_by_exception();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr size_t index() const noexcept { return __impl_.index(); }
+
+ template < bool _Dummy = true,
+ enable_if_t< __all<(__dependent_type<is_move_constructible<_Types>, _Dummy>::value &&
+ __dependent_type<is_swappable<_Types>, _Dummy>::value)...>::value,
+ int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(variant& __that) noexcept(
+ __all<(is_nothrow_move_constructible_v<_Types> && is_nothrow_swappable_v<_Types>)...>::value) {
+ __impl_.__swap(__that.__impl_);
+ }
+
+# if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_HAS_EXPLICIT_THIS_PARAMETER)
+ // Helper class to implement [variant.visit]/10
+ // Constraints: The call to visit does not use an explicit template-argument-list
+ // that begins with a type template-argument.
+ struct __variant_visit_barrier_tag {
+ _LIBCPP_HIDE_FROM_ABI explicit __variant_visit_barrier_tag() = default;
+ };
+
+ template <__variant_visit_barrier_tag = __variant_visit_barrier_tag{}, class _Self, class _Visitor>
+ _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) visit(this _Self&& __self, _Visitor&& __visitor) {
+ using _VariantT = _OverrideRef<_Self&&, _CopyConst<remove_reference_t<_Self>, variant>>;
+ return std::visit(std::forward<_Visitor>(__visitor), (_VariantT)__self);
+ }
+
+ template <class _Rp, class _Self, class _Visitor>
+ _LIBCPP_HIDE_FROM_ABI constexpr _Rp visit(this _Self&& __self, _Visitor&& __visitor) {
+ using _VariantT = _OverrideRef<_Self&&, _CopyConst<remove_reference_t<_Self>, variant>>;
+ return std::visit<_Rp>(std::forward<_Visitor>(__visitor), (_VariantT)__self);
+ }
+# endif
+
+private:
+ __variant_detail::__impl<_Types...> __impl_;
+
+ friend struct __variant_detail::__access::__variant;
+ friend struct __variant_detail::__visitation::__variant;
+};
+
+template <size_t _Ip, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr bool __holds_alternative(const variant<_Types...>& __v) noexcept {
+ return __v.index() == _Ip;
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr bool holds_alternative(const variant<_Types...>& __v) noexcept {
+ return std::__holds_alternative<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
+}
+
+template <size_t _Ip, class _Vp>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr auto&& __generic_get(_Vp&& __v) {
+ using __variant_detail::__access::__variant;
+ if (!std::__holds_alternative<_Ip>(__v)) {
+ __throw_bad_variant_access();
+ }
+ return __variant::__get_alt<_Ip>(std::forward<_Vp>(__v)).__value;
+}
+
+template <size_t _Ip, class... _Types>
+_LIBCPP_HIDE_FROM_ABI
+_LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr variant_alternative_t<_Ip, variant<_Types...>>&
+get(variant<_Types...>& __v) {
+ static_assert(_Ip < sizeof...(_Types));
+ static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
+ return std::__generic_get<_Ip>(__v);
+}
+
+template <size_t _Ip, class... _Types>
+_LIBCPP_HIDE_FROM_ABI
+_LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr variant_alternative_t<_Ip, variant<_Types...>>&&
+get(variant<_Types...>&& __v) {
+ static_assert(_Ip < sizeof...(_Types));
+ static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
+ return std::__generic_get<_Ip>(std::move(__v));
+}
+
+template <size_t _Ip, class... _Types>
+_LIBCPP_HIDE_FROM_ABI
+_LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr const variant_alternative_t<_Ip, variant<_Types...>>&
+get(const variant<_Types...>& __v) {
+ static_assert(_Ip < sizeof...(_Types));
+ static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
+ return std::__generic_get<_Ip>(__v);
+}
+
+template <size_t _Ip, class... _Types>
+_LIBCPP_HIDE_FROM_ABI
+_LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr const variant_alternative_t<_Ip, variant<_Types...>>&&
+get(const variant<_Types...>&& __v) {
+ static_assert(_Ip < sizeof...(_Types));
+ static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
+ return std::__generic_get<_Ip>(std::move(__v));
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr _Tp& get(variant<_Types...>& __v) {
+ static_assert(!is_void_v<_Tp>);
+ return std::get<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr _Tp&& get(variant<_Types...>&& __v) {
+ static_assert(!is_void_v<_Tp>);
+ return std::get<__find_exactly_one_t<_Tp, _Types...>::value>(std::move(__v));
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr const _Tp&
+get(const variant<_Types...>& __v) {
+ static_assert(!is_void_v<_Tp>);
+ return std::get<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr const _Tp&&
+get(const variant<_Types...>&& __v) {
+ static_assert(!is_void_v<_Tp>);
+ return std::get<__find_exactly_one_t<_Tp, _Types...>::value>(std::move(__v));
+}
+
+template <size_t _Ip, class _Vp>
+_LIBCPP_HIDE_FROM_ABI constexpr auto* __generic_get_if(_Vp* __v) noexcept {
+ using __variant_detail::__access::__variant;
+ return __v && std::__holds_alternative<_Ip>(*__v) ? std::addressof(__variant::__get_alt<_Ip>(*__v).__value) : nullptr;
+}
+
+template <size_t _Ip, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr add_pointer_t<variant_alternative_t<_Ip, variant<_Types...>>>
+get_if(variant<_Types...>* __v) noexcept {
+ static_assert(_Ip < sizeof...(_Types));
+ static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
+ return std::__generic_get_if<_Ip>(__v);
+}
+
+template <size_t _Ip, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr add_pointer_t<const variant_alternative_t<_Ip, variant<_Types...>>>
+get_if(const variant<_Types...>* __v) noexcept {
+ static_assert(_Ip < sizeof...(_Types));
+ static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
+ return std::__generic_get_if<_Ip>(__v);
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr add_pointer_t<_Tp> get_if(variant<_Types...>* __v) noexcept {
+ static_assert(!is_void_v<_Tp>);
+ return std::get_if<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr add_pointer_t<const _Tp> get_if(const variant<_Types...>* __v) noexcept {
+ static_assert(!is_void_v<_Tp>);
+ return std::get_if<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
+}
+
+template <class _Operator>
+struct __convert_to_bool {
+ template <class _T1, class _T2>
+ _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_T1&& __t1, _T2&& __t2) const {
+ static_assert(is_convertible<decltype(_Operator{}(std::forward<_T1>(__t1), std::forward<_T2>(__t2))), bool>::value,
+ "the relational operator does not return a type which is implicitly convertible to bool");
+ return _Operator{}(std::forward<_T1>(__t1), std::forward<_T2>(__t2));
+ }
+};
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator==(const variant<_Types...>& __lhs, const variant<_Types...>& __rhs) {
+ using __variant_detail::__visitation::__variant;
+ if (__lhs.index() != __rhs.index())
+ return false;
+ if (__lhs.valueless_by_exception())
+ return true;
+ return __variant::__visit_value_at(__lhs.index(), __convert_to_bool<equal_to<>>{}, __lhs, __rhs);
+}
+
+# if _LIBCPP_STD_VER >= 20
+
+template <class... _Types>
+ requires(three_way_comparable<_Types> && ...)
+_LIBCPP_HIDE_FROM_ABI constexpr common_comparison_category_t<compare_three_way_result_t<_Types>...>
+operator<=>(const variant<_Types...>& __lhs, const variant<_Types...>& __rhs) {
+ using __variant_detail::__visitation::__variant;
+ using __result_t = common_comparison_category_t<compare_three_way_result_t<_Types>...>;
+ if (__lhs.valueless_by_exception() && __rhs.valueless_by_exception())
+ return strong_ordering::equal;
+ if (__lhs.valueless_by_exception())
+ return strong_ordering::less;
+ if (__rhs.valueless_by_exception())
+ return strong_ordering::greater;
+ if (auto __c = __lhs.index() <=> __rhs.index(); __c != 0)
+ return __c;
+ auto __three_way = []<class _Type>(const _Type& __v, const _Type& __w) -> __result_t { return __v <=> __w; };
+ return __variant::__visit_value_at(__lhs.index(), __three_way, __lhs, __rhs);
+}
+
+# endif // _LIBCPP_STD_VER >= 20
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(const variant<_Types...>& __lhs, const variant<_Types...>& __rhs) {
+ using __variant_detail::__visitation::__variant;
+ if (__lhs.index() != __rhs.index())
+ return true;
+ if (__lhs.valueless_by_exception())
+ return false;
+ return __variant::__visit_value_at(__lhs.index(), __convert_to_bool<not_equal_to<>>{}, __lhs, __rhs);
+}
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<(const variant<_Types...>& __lhs, const variant<_Types...>& __rhs) {
+ using __variant_detail::__visitation::__variant;
+ if (__rhs.valueless_by_exception())
+ return false;
+ if (__lhs.valueless_by_exception())
+ return true;
+ if (__lhs.index() < __rhs.index())
+ return true;
+ if (__lhs.index() > __rhs.index())
+ return false;
+ return __variant::__visit_value_at(__lhs.index(), __convert_to_bool<less<>>{}, __lhs, __rhs);
+}
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>(const variant<_Types...>& __lhs, const variant<_Types...>& __rhs) {
+ using __variant_detail::__visitation::__variant;
+ if (__lhs.valueless_by_exception())
+ return false;
+ if (__rhs.valueless_by_exception())
+ return true;
+ if (__lhs.index() > __rhs.index())
+ return true;
+ if (__lhs.index() < __rhs.index())
+ return false;
+ return __variant::__visit_value_at(__lhs.index(), __convert_to_bool<greater<>>{}, __lhs, __rhs);
+}
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(const variant<_Types...>& __lhs, const variant<_Types...>& __rhs) {
+ using __variant_detail::__visitation::__variant;
+ if (__lhs.valueless_by_exception())
+ return true;
+ if (__rhs.valueless_by_exception())
+ return false;
+ if (__lhs.index() < __rhs.index())
+ return true;
+ if (__lhs.index() > __rhs.index())
+ return false;
+ return __variant::__visit_value_at(__lhs.index(), __convert_to_bool<less_equal<>>{}, __lhs, __rhs);
+}
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(const variant<_Types...>& __lhs, const variant<_Types...>& __rhs) {
+ using __variant_detail::__visitation::__variant;
+ if (__rhs.valueless_by_exception())
+ return true;
+ if (__lhs.valueless_by_exception())
+ return false;
+ if (__lhs.index() > __rhs.index())
+ return true;
+ if (__lhs.index() < __rhs.index())
+ return false;
+ return __variant::__visit_value_at(__lhs.index(), __convert_to_bool<greater_equal<>>{}, __lhs, __rhs);
+}
+
+template <class... _Vs>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr void __throw_if_valueless(_Vs&&... __vs) {
+ const bool __valueless = (... || std::__as_variant(__vs).valueless_by_exception());
+ if (__valueless) {
+ __throw_bad_variant_access();
+ }
+}
+
+template < class _Visitor, class... _Vs, typename>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr decltype(auto)
+visit(_Visitor&& __visitor, _Vs&&... __vs) {
+ using __variant_detail::__visitation::__variant;
+ std::__throw_if_valueless(std::forward<_Vs>(__vs)...);
+ return __variant::__visit_value(std::forward<_Visitor>(__visitor), std::forward<_Vs>(__vs)...);
+}
+
+# if _LIBCPP_STD_VER >= 20
+template < class _Rp, class _Visitor, class... _Vs, typename>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr _Rp
+visit(_Visitor&& __visitor, _Vs&&... __vs) {
+ using __variant_detail::__visitation::__variant;
+ std::__throw_if_valueless(std::forward<_Vs>(__vs)...);
+ return __variant::__visit_value<_Rp>(std::forward<_Visitor>(__visitor), std::forward<_Vs>(__vs)...);
+}
+# endif
+
+template <class... _Types>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 auto
+swap(variant<_Types...>& __lhs,
+ variant<_Types...>& __rhs) noexcept(noexcept(__lhs.swap(__rhs))) -> decltype(__lhs.swap(__rhs)) {
+ return __lhs.swap(__rhs);
+}
+
+template <class... _Types>
+struct _LIBCPP_TEMPLATE_VIS hash< __enable_hash_helper<variant<_Types...>, remove_const_t<_Types>...>> {
+ using argument_type = variant<_Types...>;
+ using result_type = size_t;
+
+ _LIBCPP_HIDE_FROM_ABI result_type operator()(const argument_type& __v) const {
+ using __variant_detail::__visitation::__variant;
+ size_t __res =
+ __v.valueless_by_exception()
+ ? 299792458 // Random value chosen by the universe upon creation
+ : __variant::__visit_alt(
+ [](const auto& __alt) {
+ using __alt_type = __remove_cvref_t<decltype(__alt)>;
+ using __value_type = remove_const_t< typename __alt_type::__value_type>;
+ return hash<__value_type>{}(__alt.__value);
+ },
+ __v);
+ return std::__hash_combine(__res, hash<size_t>{}(__v.index()));
+ }
+};
+
+// __unchecked_get is the same as std::get, except, it is UB to use it with the wrong
+// type whereas std::get will throw or returning nullptr. This makes it faster than
+// std::get.
+template <size_t _Ip, class _Vp>
+_LIBCPP_HIDE_FROM_ABI constexpr auto&& __unchecked_get(_Vp&& __v) noexcept {
+ using __variant_detail::__access::__variant;
+ return __variant::__get_alt<_Ip>(std::forward<_Vp>(__v)).__value;
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr auto&& __unchecked_get(const variant<_Types...>& __v) noexcept {
+ return std::__unchecked_get<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
+}
+
+template <class _Tp, class... _Types>
+_LIBCPP_HIDE_FROM_ABI constexpr auto&& __unchecked_get(variant<_Types...>& __v) noexcept {
+ return std::__unchecked_get<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <exception>
+# include <tuple>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_VARIANT
diff --git a/libcxx/include/__cxx03/vector b/libcxx/include/__cxx03/vector
new file mode 100644
index 00000000000000..4d83d4b6edda84
--- /dev/null
+++ b/libcxx/include/__cxx03/vector
@@ -0,0 +1,3031 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_VECTOR
+#define _LIBCPP_VECTOR
+
+// clang-format off
+
+/*
+ vector synopsis
+
+namespace std
+{
+
+template <class T, class Allocator = allocator<T> >
+class vector
+{
+public:
+ typedef T value_type;
+ typedef Allocator allocator_type;
+ typedef typename allocator_type::reference reference;
+ typedef typename allocator_type::const_reference const_reference;
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef typename allocator_type::size_type size_type;
+ typedef typename allocator_type::difference_type difference_type;
+ typedef typename allocator_type::pointer pointer;
+ typedef typename allocator_type::const_pointer const_pointer;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+ vector()
+ noexcept(is_nothrow_default_constructible<allocator_type>::value);
+ explicit vector(const allocator_type&);
+ explicit vector(size_type n);
+ explicit vector(size_type n, const allocator_type&); // C++14
+ vector(size_type n, const value_type& value, const allocator_type& = allocator_type());
+ template <class InputIterator>
+ vector(InputIterator first, InputIterator last, const allocator_type& = allocator_type());
+ template<container-compatible-range<T> R>
+ constexpr vector(from_range_t, R&& rg, const Allocator& = Allocator()); // C++23
+ vector(const vector& x);
+ vector(vector&& x)
+ noexcept(is_nothrow_move_constructible<allocator_type>::value);
+ vector(initializer_list<value_type> il);
+ vector(initializer_list<value_type> il, const allocator_type& a);
+ ~vector();
+ vector& operator=(const vector& x);
+ vector& operator=(vector&& x)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value ||
+ allocator_type::is_always_equal::value); // C++17
+ vector& operator=(initializer_list<value_type> il);
+ template <class InputIterator>
+ void assign(InputIterator first, InputIterator last);
+ template<container-compatible-range<T> R>
+ constexpr void assign_range(R&& rg); // C++23
+ void assign(size_type n, const value_type& u);
+ void assign(initializer_list<value_type> il);
+
+ allocator_type get_allocator() const noexcept;
+
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+
+ reverse_iterator rbegin() noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ reverse_iterator rend() noexcept;
+ const_reverse_iterator rend() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+ size_type capacity() const noexcept;
+ bool empty() const noexcept;
+ void reserve(size_type n);
+ void shrink_to_fit() noexcept;
+
+ reference operator[](size_type n);
+ const_reference operator[](size_type n) const;
+ reference at(size_type n);
+ const_reference at(size_type n) const;
+
+ reference front();
+ const_reference front() const;
+ reference back();
+ const_reference back() const;
+
+ value_type* data() noexcept;
+ const value_type* data() const noexcept;
+
+ void push_back(const value_type& x);
+ void push_back(value_type&& x);
+ template <class... Args>
+ reference emplace_back(Args&&... args); // reference in C++17
+ template<container-compatible-range<T> R>
+ constexpr void append_range(R&& rg); // C++23
+ void pop_back();
+
+ template <class... Args> iterator emplace(const_iterator position, Args&&... args);
+ iterator insert(const_iterator position, const value_type& x);
+ iterator insert(const_iterator position, value_type&& x);
+ iterator insert(const_iterator position, size_type n, const value_type& x);
+ template <class InputIterator>
+ iterator insert(const_iterator position, InputIterator first, InputIterator last);
+ template<container-compatible-range<T> R>
+ constexpr iterator insert_range(const_iterator position, R&& rg); // C++23
+ iterator insert(const_iterator position, initializer_list<value_type> il);
+
+ iterator erase(const_iterator position);
+ iterator erase(const_iterator first, const_iterator last);
+
+ void clear() noexcept;
+
+ void resize(size_type sz);
+ void resize(size_type sz, const value_type& c);
+
+ void swap(vector&)
+ noexcept(allocator_traits<allocator_type>::propagate_on_container_swap::value ||
+ allocator_traits<allocator_type>::is_always_equal::value); // C++17
+
+ bool __invariants() const;
+};
+
+template <class Allocator = allocator<T> >
+class vector<bool, Allocator>
+{
+public:
+ typedef bool value_type;
+ typedef Allocator allocator_type;
+ typedef implementation-defined iterator;
+ typedef implementation-defined const_iterator;
+ typedef typename allocator_type::size_type size_type;
+ typedef typename allocator_type::difference_type difference_type;
+ typedef iterator pointer;
+ typedef const_iterator const_pointer;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+ class reference
+ {
+ public:
+ reference(const reference&) noexcept;
+ operator bool() const noexcept;
+ reference& operator=(bool x) noexcept;
+ reference& operator=(const reference& x) noexcept;
+ iterator operator&() const noexcept;
+ void flip() noexcept;
+ };
+
+ class const_reference
+ {
+ public:
+ const_reference(const reference&) noexcept;
+ operator bool() const noexcept;
+ const_iterator operator&() const noexcept;
+ };
+
+ vector()
+ noexcept(is_nothrow_default_constructible<allocator_type>::value);
+ explicit vector(const allocator_type&);
+ explicit vector(size_type n, const allocator_type& a = allocator_type()); // C++14
+ vector(size_type n, const value_type& value, const allocator_type& = allocator_type());
+ template <class InputIterator>
+ vector(InputIterator first, InputIterator last, const allocator_type& = allocator_type());
+ template<container-compatible-range<bool> R>
+ constexpr vector(from_range_t, R&& rg, const Allocator& = Allocator());
+ vector(const vector& x);
+ vector(vector&& x)
+ noexcept(is_nothrow_move_constructible<allocator_type>::value);
+ vector(initializer_list<value_type> il);
+ vector(initializer_list<value_type> il, const allocator_type& a);
+ ~vector();
+ vector& operator=(const vector& x);
+ vector& operator=(vector&& x)
+ noexcept(
+ allocator_type::propagate_on_container_move_assignment::value ||
+ allocator_type::is_always_equal::value); // C++17
+ vector& operator=(initializer_list<value_type> il);
+ template <class InputIterator>
+ void assign(InputIterator first, InputIterator last);
+ template<container-compatible-range<T> R>
+ constexpr void assign_range(R&& rg); // C++23
+ void assign(size_type n, const value_type& u);
+ void assign(initializer_list<value_type> il);
+
+ allocator_type get_allocator() const noexcept;
+
+ iterator begin() noexcept;
+ const_iterator begin() const noexcept;
+ iterator end() noexcept;
+ const_iterator end() const noexcept;
+
+ reverse_iterator rbegin() noexcept;
+ const_reverse_iterator rbegin() const noexcept;
+ reverse_iterator rend() noexcept;
+ const_reverse_iterator rend() const noexcept;
+
+ const_iterator cbegin() const noexcept;
+ const_iterator cend() const noexcept;
+ const_reverse_iterator crbegin() const noexcept;
+ const_reverse_iterator crend() const noexcept;
+
+ size_type size() const noexcept;
+ size_type max_size() const noexcept;
+ size_type capacity() const noexcept;
+ bool empty() const noexcept;
+ void reserve(size_type n);
+ void shrink_to_fit() noexcept;
+
+ reference operator[](size_type n);
+ const_reference operator[](size_type n) const;
+ reference at(size_type n);
+ const_reference at(size_type n) const;
+
+ reference front();
+ const_reference front() const;
+ reference back();
+ const_reference back() const;
+
+ void push_back(const value_type& x);
+ template <class... Args> reference emplace_back(Args&&... args); // C++14; reference in C++17
+ template<container-compatible-range<T> R>
+ constexpr void append_range(R&& rg); // C++23
+ void pop_back();
+
+ template <class... Args> iterator emplace(const_iterator position, Args&&... args); // C++14
+ iterator insert(const_iterator position, const value_type& x);
+ iterator insert(const_iterator position, size_type n, const value_type& x);
+ template <class InputIterator>
+ iterator insert(const_iterator position, InputIterator first, InputIterator last);
+ template<container-compatible-range<T> R>
+ constexpr iterator insert_range(const_iterator position, R&& rg); // C++23
+ iterator insert(const_iterator position, initializer_list<value_type> il);
+
+ iterator erase(const_iterator position);
+ iterator erase(const_iterator first, const_iterator last);
+
+ void clear() noexcept;
+
+ void resize(size_type sz);
+ void resize(size_type sz, value_type x);
+
+ void swap(vector&)
+ noexcept(allocator_traits<allocator_type>::propagate_on_container_swap::value ||
+ allocator_traits<allocator_type>::is_always_equal::value); // C++17
+ void flip() noexcept;
+
+ bool __invariants() const;
+};
+
+template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+ vector(InputIterator, InputIterator, Allocator = Allocator())
+ -> vector<typename iterator_traits<InputIterator>::value_type, Allocator>; // C++17
+
+template<ranges::input_range R, class Allocator = allocator<ranges::range_value_t<R>>>
+ vector(from_range_t, R&&, Allocator = Allocator())
+ -> vector<ranges::range_value_t<R>, Allocator>; // C++23
+
+template <class Allocator> struct hash<std::vector<bool, Allocator>>;
+
+template <class T, class Allocator> bool operator==(const vector<T,Allocator>& x, const vector<T,Allocator>& y); // constexpr since C++20
+template <class T, class Allocator> bool operator!=(const vector<T,Allocator>& x, const vector<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator> bool operator< (const vector<T,Allocator>& x, const vector<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator> bool operator> (const vector<T,Allocator>& x, const vector<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator> bool operator>=(const vector<T,Allocator>& x, const vector<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator> bool operator<=(const vector<T,Allocator>& x, const vector<T,Allocator>& y); // removed in C++20
+template <class T, class Allocator> constexpr
+ constexpr synth-three-way-result<T> operator<=>(const vector<T, Allocator>& x,
+ const vector<T, Allocator>& y); // since C++20
+
+template <class T, class Allocator>
+void swap(vector<T,Allocator>& x, vector<T,Allocator>& y)
+ noexcept(noexcept(x.swap(y)));
+
+template <class T, class Allocator, class U>
+typename vector<T, Allocator>::size_type
+erase(vector<T, Allocator>& c, const U& value); // since C++20
+template <class T, class Allocator, class Predicate>
+typename vector<T, Allocator>::size_type
+erase_if(vector<T, Allocator>& c, Predicate pred); // since C++20
+
+
+template<class T>
+ inline constexpr bool is-vector-bool-reference = see below; // exposition only, since C++23
+
+template<class T, class charT> requires is-vector-bool-reference<T> // Since C++23
+ struct formatter<T, charT>;
+
+} // std
+
+*/
+
+// clang-format on
+
+#include <__algorithm/copy.h>
+#include <__algorithm/equal.h>
+#include <__algorithm/fill_n.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/lexicographical_compare.h>
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__algorithm/remove.h>
+#include <__algorithm/remove_if.h>
+#include <__algorithm/rotate.h>
+#include <__algorithm/unwrap_iter.h>
+#include <__assert>
+#include <__bit_reference>
+#include <__concepts/same_as.h>
+#include <__config>
+#include <__debug_utils/sanitizers.h>
+#include <__format/enable_insertable.h>
+#include <__format/formatter.h>
+#include <__format/formatter_bool.h>
+#include <__functional/hash.h>
+#include <__functional/unary_function.h>
+#include <__fwd/vector.h>
+#include <__iterator/advance.h>
+#include <__iterator/bounded_iter.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__iterator/wrap_iter.h>
+#include <__memory/addressof.h>
+#include <__memory/allocate_at_least.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__memory/swap_allocator.h>
+#include <__memory/temp_value.h>
+#include <__memory/uninitialized_algorithms.h>
+#include <__memory_resource/polymorphic_allocator.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/from_range.h>
+#include <__ranges/size.h>
+#include <__split_buffer>
+#include <__type_traits/is_allocator.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_nothrow_assignable.h>
+#include <__type_traits/noexcept_move_assign_container.h>
+#include <__type_traits/type_identity.h>
+#include <__utility/exception_guard.h>
+#include <__utility/forward.h>
+#include <__utility/is_pointer_in_range.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/swap.h>
+#include <climits>
+#include <cstring>
+#include <limits>
+#include <stdexcept>
+#include <version>
+
+// standard-mandated includes
+
+// [iterator.range]
+#include <__iterator/access.h>
+#include <__iterator/data.h>
+#include <__iterator/empty.h>
+#include <__iterator/reverse_access.h>
+#include <__iterator/size.h>
+
+// [vector.syn]
+#include <compare>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, class _Allocator /* = allocator<_Tp> */>
+class _LIBCPP_TEMPLATE_VIS vector {
+private:
+ typedef allocator<_Tp> __default_allocator_type;
+
+public:
+ typedef vector __self;
+ typedef _Tp value_type;
+ typedef _Allocator allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+ typedef typename __alloc_traits::size_type size_type;
+ typedef typename __alloc_traits::difference_type difference_type;
+ typedef typename __alloc_traits::pointer pointer;
+ typedef typename __alloc_traits::const_pointer const_pointer;
+#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS_IN_VECTOR
+ // Users might provide custom allocators, and prior to C++20 we have no existing way to detect whether the allocator's
+ // pointer type is contiguous (though it has to be by the Standard). Using the wrapper type ensures the iterator is
+ // considered contiguous.
+ typedef __bounded_iter<__wrap_iter<pointer>> iterator;
+ typedef __bounded_iter<__wrap_iter<const_pointer>> const_iterator;
+#else
+ typedef __wrap_iter<pointer> iterator;
+ typedef __wrap_iter<const_pointer> const_iterator;
+#endif
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+ // A vector containers the following members which may be trivially relocatable:
+ // - pointer: may be trivially relocatable, so it's checked
+ // - allocator_type: may be trivially relocatable, so it's checked
+ // vector doesn't contain any self-references, so it's trivially relocatable if its members are.
+ using __trivially_relocatable = __conditional_t<
+ __libcpp_is_trivially_relocatable<pointer>::value && __libcpp_is_trivially_relocatable<allocator_type>::value,
+ vector,
+ void>;
+
+ static_assert(__check_valid_allocator<allocator_type>::value, "");
+ static_assert(is_same<typename allocator_type::value_type, value_type>::value,
+ "Allocator::value_type must be same type as value_type");
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector()
+ _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value) {}
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(const allocator_type& __a)
+#if _LIBCPP_STD_VER <= 14
+ _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
+#else
+ _NOEXCEPT
+#endif
+ : __end_cap_(nullptr, __a) {
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(size_type __n) {
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__n);
+ }
+ __guard.__complete();
+ }
+
+#if _LIBCPP_STD_VER >= 14
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(size_type __n, const allocator_type& __a)
+ : __end_cap_(nullptr, __a) {
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__n);
+ }
+ __guard.__complete();
+ }
+#endif
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(size_type __n, const value_type& __x) {
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__n, __x);
+ }
+ __guard.__complete();
+ }
+
+ template <__enable_if_t<__is_allocator<_Allocator>::value, int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+ vector(size_type __n, const value_type& __x, const allocator_type& __a)
+ : __end_cap_(nullptr, __a) {
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__n, __x);
+ }
+ }
+
+ template <class _InputIterator,
+ __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value &&
+ is_constructible<value_type, typename iterator_traits<_InputIterator>::reference>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator,
+ __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value &&
+ is_constructible<value_type, typename iterator_traits<_InputIterator>::reference>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+ vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a);
+
+ template <
+ class _ForwardIterator,
+ __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value &&
+ is_constructible<value_type, typename iterator_traits<_ForwardIterator>::reference>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(_ForwardIterator __first, _ForwardIterator __last);
+
+ template <
+ class _ForwardIterator,
+ __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value &&
+ is_constructible<value_type, typename iterator_traits<_ForwardIterator>::reference>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+ vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr vector(
+ from_range_t, _Range&& __range, const allocator_type& __alloc = allocator_type())
+ : __end_cap_(nullptr, __alloc) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ __init_with_size(ranges::begin(__range), ranges::end(__range), __n);
+
+ } else {
+ __init_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+private:
+ class __destroy_vector {
+ public:
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI __destroy_vector(vector& __vec) : __vec_(__vec) {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void operator()() {
+ if (__vec_.__begin_ != nullptr) {
+ __vec_.__clear();
+ __vec_.__annotate_delete();
+ __alloc_traits::deallocate(__vec_.__alloc(), __vec_.__begin_, __vec_.capacity());
+ }
+ }
+
+ private:
+ vector& __vec_;
+ };
+
+public:
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~vector() { __destroy_vector (*this)(); }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(const vector& __x);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+ vector(const vector& __x, const __type_identity_t<allocator_type>& __a);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector& operator=(const vector& __x);
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(initializer_list<value_type> __il);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+ vector(initializer_list<value_type> __il, const allocator_type& __a);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector& operator=(initializer_list<value_type> __il) {
+ assign(__il.begin(), __il.end());
+ return *this;
+ }
+#endif // !_LIBCPP_CXX03_LANG
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(vector&& __x)
+#if _LIBCPP_STD_VER >= 17
+ noexcept;
+#else
+ _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
+#endif
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+ vector(vector&& __x, const __type_identity_t<allocator_type>& __a);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector& operator=(vector&& __x)
+ _NOEXCEPT_(__noexcept_move_assign_container<_Allocator, __alloc_traits>::value);
+
+ template <class _InputIterator,
+ __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value &&
+ is_constructible<value_type, typename iterator_traits<_InputIterator>::reference>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void assign(_InputIterator __first, _InputIterator __last);
+ template <
+ class _ForwardIterator,
+ __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value &&
+ is_constructible<value_type, typename iterator_traits<_ForwardIterator>::reference>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void assign(_ForwardIterator __first, _ForwardIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr void assign_range(_Range&& __range) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ __assign_with_size(ranges::begin(__range), ranges::end(__range), __n);
+
+ } else {
+ __assign_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void assign(size_type __n, const_reference __u);
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void assign(initializer_list<value_type> __il) {
+ assign(__il.begin(), __il.end());
+ }
+#endif
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const _NOEXCEPT {
+ return this->__alloc();
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() _NOEXCEPT {
+ return reverse_iterator(end());
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const _NOEXCEPT {
+ return const_reverse_iterator(end());
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() _NOEXCEPT {
+ return reverse_iterator(begin());
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const _NOEXCEPT {
+ return const_reverse_iterator(begin());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const _NOEXCEPT { return begin(); }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator cend() const _NOEXCEPT { return end(); }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const _NOEXCEPT {
+ return rbegin();
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type size() const _NOEXCEPT {
+ return static_cast<size_type>(this->__end_ - this->__begin_);
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type capacity() const _NOEXCEPT {
+ return static_cast<size_type>(__end_cap() - this->__begin_);
+ }
+ _LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool empty() const _NOEXCEPT {
+ return this->__begin_ == this->__end_;
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void shrink_to_fit() _NOEXCEPT;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference operator[](size_type __n) _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference operator[](size_type __n) const _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference at(size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference at(size_type __n) const;
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference front() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "front() called on an empty vector");
+ return *this->__begin_;
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference front() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "front() called on an empty vector");
+ return *this->__begin_;
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference back() _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "back() called on an empty vector");
+ return *(this->__end_ - 1);
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference back() const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "back() called on an empty vector");
+ return *(this->__end_ - 1);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI value_type* data() _NOEXCEPT {
+ return std::__to_address(this->__begin_);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const value_type* data() const _NOEXCEPT {
+ return std::__to_address(this->__begin_);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(const_reference __x);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(value_type&& __x);
+
+ template <class... _Args>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
+#if _LIBCPP_STD_VER >= 17
+ reference
+ emplace_back(_Args&&... __args);
+#else
+ void
+ emplace_back(_Args&&... __args);
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr void append_range(_Range&& __range) {
+ insert_range(end(), std::forward<_Range>(__range));
+ }
+#endif
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void pop_back();
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __position, const_reference __x);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __position, value_type&& __x);
+ template <class... _Args>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator emplace(const_iterator __position, _Args&&... __args);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
+ insert(const_iterator __position, size_type __n, const_reference __x);
+
+ template <class _InputIterator,
+ __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value &&
+ is_constructible< value_type, typename iterator_traits<_InputIterator>::reference>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
+ insert(const_iterator __position, _InputIterator __first, _InputIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<_Tp> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator insert_range(const_iterator __position, _Range&& __range) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ return __insert_with_size(__position, ranges::begin(__range), ranges::end(__range), __n);
+
+ } else {
+ return __insert_with_sentinel(__position, ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+ template <
+ class _ForwardIterator,
+ __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value &&
+ is_constructible< value_type, typename iterator_traits<_ForwardIterator>::reference>::value,
+ int> = 0>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
+ insert(const_iterator __position, _ForwardIterator __first, _ForwardIterator __last);
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
+ insert(const_iterator __position, initializer_list<value_type> __il) {
+ return insert(__position, __il.begin(), __il.end());
+ }
+#endif
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __position);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT {
+ size_type __old_size = size();
+ __clear();
+ __annotate_shrink(__old_size);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void resize(size_type __sz);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void resize(size_type __sz, const_reference __x);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void swap(vector&)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT;
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>);
+#endif
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __invariants() const;
+
+private:
+ pointer __begin_ = nullptr;
+ pointer __end_ = nullptr;
+ __compressed_pair<pointer, allocator_type> __end_cap_ =
+ __compressed_pair<pointer, allocator_type>(nullptr, __default_init_tag());
+
+ // Allocate space for __n objects
+ // throws length_error if __n > max_size()
+ // throws (probably bad_alloc) if memory run out
+ // Precondition: __begin_ == __end_ == __end_cap() == 0
+ // Precondition: __n > 0
+ // Postcondition: capacity() >= __n
+ // Postcondition: size() == 0
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __vallocate(size_type __n) {
+ if (__n > max_size())
+ __throw_length_error();
+ auto __allocation = std::__allocate_at_least(__alloc(), __n);
+ __begin_ = __allocation.ptr;
+ __end_ = __allocation.ptr;
+ __end_cap() = __begin_ + __allocation.count;
+ __annotate_new(0);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __vdeallocate() _NOEXCEPT;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type __recommend(size_type __new_size) const;
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n, const_reference __x);
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __init_with_size(_InputIterator __first, _Sentinel __last, size_type __n) {
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__first, __last, __n);
+ }
+
+ __guard.__complete();
+ }
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __init_with_sentinel(_InputIterator __first, _Sentinel __last) {
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+
+ for (; __first != __last; ++__first)
+ emplace_back(*__first);
+
+ __guard.__complete();
+ }
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __assign_with_sentinel(_Iterator __first, _Sentinel __last);
+
+ template <class _ForwardIterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __assign_with_size(_ForwardIterator __first, _Sentinel __last, difference_type __n);
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
+ __insert_with_sentinel(const_iterator __position, _InputIterator __first, _Sentinel __last);
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
+ __insert_with_size(const_iterator __position, _Iterator __first, _Sentinel __last, difference_type __n);
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __construct_at_end(_InputIterator __first, _Sentinel __last, size_type __n);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __append(size_type __n);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __append(size_type __n, const_reference __x);
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator __make_iter(pointer __p) _NOEXCEPT {
+#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS_IN_VECTOR
+ // Bound the iterator according to the capacity, rather than the size.
+ //
+ // Vector guarantees that iterators stay valid as long as no reallocation occurs even if new elements are inserted
+ // into the container; for these cases, we need to make sure that the newly-inserted elements can be accessed
+ // through the bounded iterator without failing checks. The downside is that the bounded iterator won't catch
+ // access that is logically out-of-bounds, i.e., goes beyond the size, but is still within the capacity. With the
+ // current implementation, there is no connection between a bounded iterator and its associated container, so we
+ // don't have a way to update existing valid iterators when the container is resized and thus have to go with
+ // a laxer approach.
+ return std::__make_bounded_iter(
+ std::__wrap_iter<pointer>(__p),
+ std::__wrap_iter<pointer>(this->__begin_),
+ std::__wrap_iter<pointer>(this->__end_cap()));
+#else
+ return iterator(__p);
+#endif // _LIBCPP_ABI_BOUNDED_ITERATORS_IN_VECTOR
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator __make_iter(const_pointer __p) const _NOEXCEPT {
+#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS_IN_VECTOR
+ // Bound the iterator according to the capacity, rather than the size.
+ return std::__make_bounded_iter(
+ std::__wrap_iter<const_pointer>(__p),
+ std::__wrap_iter<const_pointer>(this->__begin_),
+ std::__wrap_iter<const_pointer>(this->__end_cap()));
+#else
+ return const_iterator(__p);
+#endif // _LIBCPP_ABI_BOUNDED_ITERATORS_IN_VECTOR
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pointer
+ __swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v, pointer __p);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __move_range(pointer __from_s, pointer __from_e, pointer __to);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign(vector& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign(vector& __c, false_type)
+ _NOEXCEPT_(__alloc_traits::is_always_equal::value);
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last) _NOEXCEPT {
+ size_type __old_size = size();
+ __base_destruct_at_end(__new_last);
+ __annotate_shrink(__old_size);
+ }
+
+ template <class _Up>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI inline pointer __push_back_slow_path(_Up&& __x);
+
+ template <class... _Args>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI inline pointer __emplace_back_slow_path(_Args&&... __args);
+
+ // The following functions are no-ops outside of AddressSanitizer mode.
+ // We call annotations for every allocator, unless explicitly disabled.
+ //
+ // To disable annotations for a particular allocator, change value of
+ // __asan_annotate_container_with_allocator to false.
+ // For more details, see the "Using libc++" documentation page or
+ // the documentation for __sanitizer_annotate_contiguous_container.
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __annotate_contiguous_container(const void* __old_mid, const void* __new_mid) const {
+ std::__annotate_contiguous_container<_Allocator>(data(), data() + capacity(), __old_mid, __new_mid);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __annotate_new(size_type __current_size) const _NOEXCEPT {
+ (void)__current_size;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __annotate_contiguous_container(data() + capacity(), data() + __current_size);
+#endif
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __annotate_delete() const _NOEXCEPT {
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __annotate_contiguous_container(data() + size(), data() + capacity());
+#endif
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __annotate_increase(size_type __n) const _NOEXCEPT {
+ (void)__n;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __annotate_contiguous_container(data() + size(), data() + size() + __n);
+#endif
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __annotate_shrink(size_type __old_size) const _NOEXCEPT {
+ (void)__old_size;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __annotate_contiguous_container(data() + __old_size, data() + size());
+#endif
+ }
+
+ struct _ConstructTransaction {
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit _ConstructTransaction(vector& __v, size_type __n)
+ : __v_(__v), __pos_(__v.__end_), __new_end_(__v.__end_ + __n) {
+#ifndef _LIBCPP_HAS_NO_ASAN
+ __v_.__annotate_increase(__n);
+#endif
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~_ConstructTransaction() {
+ __v_.__end_ = __pos_;
+#ifndef _LIBCPP_HAS_NO_ASAN
+ if (__pos_ != __new_end_) {
+ __v_.__annotate_shrink(__new_end_ - __v_.__begin_);
+ }
+#endif
+ }
+
+ vector& __v_;
+ pointer __pos_;
+ const_pointer const __new_end_;
+
+ _ConstructTransaction(_ConstructTransaction const&) = delete;
+ _ConstructTransaction& operator=(_ConstructTransaction const&) = delete;
+ };
+
+ template <class... _Args>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_one_at_end(_Args&&... __args) {
+ _ConstructTransaction __tx(*this, 1);
+ __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_), std::forward<_Args>(__args)...);
+ ++__tx.__pos_;
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI allocator_type& __alloc() _NOEXCEPT {
+ return this->__end_cap_.second();
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const allocator_type& __alloc() const _NOEXCEPT {
+ return this->__end_cap_.second();
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pointer& __end_cap() _NOEXCEPT {
+ return this->__end_cap_.first();
+ }
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const pointer& __end_cap() const _NOEXCEPT {
+ return this->__end_cap_.first();
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __clear() _NOEXCEPT {
+ __base_destruct_at_end(this->__begin_);
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __base_destruct_at_end(pointer __new_last) _NOEXCEPT {
+ pointer __soon_to_be_end = this->__end_;
+ while (__new_last != __soon_to_be_end)
+ __alloc_traits::destroy(__alloc(), std::__to_address(--__soon_to_be_end));
+ this->__end_ = __new_last;
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const vector& __c) {
+ __copy_assign_alloc(__c, integral_constant<bool, __alloc_traits::propagate_on_container_copy_assignment::value>());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(vector& __c)
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_move_assignment::value ||
+ is_nothrow_move_assignable<allocator_type>::value) {
+ __move_assign_alloc(__c, integral_constant<bool, __alloc_traits::propagate_on_container_move_assignment::value>());
+ }
+
+ _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI void __throw_length_error() const { std::__throw_length_error("vector"); }
+
+ _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI void __throw_out_of_range() const { std::__throw_out_of_range("vector"); }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const vector& __c, true_type) {
+ if (__alloc() != __c.__alloc()) {
+ __clear();
+ __annotate_delete();
+ __alloc_traits::deallocate(__alloc(), this->__begin_, capacity());
+ this->__begin_ = this->__end_ = __end_cap() = nullptr;
+ }
+ __alloc() = __c.__alloc();
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __copy_assign_alloc(const vector&, false_type) {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(vector& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
+ __alloc() = std::move(__c.__alloc());
+ }
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(vector&, false_type) _NOEXCEPT {}
+};
+
+#if _LIBCPP_STD_VER >= 17
+template <class _InputIterator,
+ class _Alloc = allocator<__iter_value_type<_InputIterator>>,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+vector(_InputIterator, _InputIterator) -> vector<__iter_value_type<_InputIterator>, _Alloc>;
+
+template <class _InputIterator,
+ class _Alloc,
+ class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+vector(_InputIterator, _InputIterator, _Alloc) -> vector<__iter_value_type<_InputIterator>, _Alloc>;
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+template <ranges::input_range _Range,
+ class _Alloc = allocator<ranges::range_value_t<_Range>>,
+ class = enable_if_t<__is_allocator<_Alloc>::value> >
+vector(from_range_t, _Range&&, _Alloc = _Alloc()) -> vector<ranges::range_value_t<_Range>, _Alloc>;
+#endif
+
+// __swap_out_circular_buffer relocates the objects in [__begin_, __end_) into the front of __v and swaps the buffers of
+// *this and __v. It is assumed that __v provides space for exactly (__end_ - __begin_) objects in the front. This
+// function has a strong exception guarantee.
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+vector<_Tp, _Allocator>::__swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v) {
+ __annotate_delete();
+ auto __new_begin = __v.__begin_ - (__end_ - __begin_);
+ std::__uninitialized_allocator_relocate(
+ __alloc(), std::__to_address(__begin_), std::__to_address(__end_), std::__to_address(__new_begin));
+ __v.__begin_ = __new_begin;
+ __end_ = __begin_; // All the objects have been destroyed by relocating them.
+ std::swap(this->__begin_, __v.__begin_);
+ std::swap(this->__end_, __v.__end_);
+ std::swap(this->__end_cap(), __v.__end_cap());
+ __v.__first_ = __v.__begin_;
+ __annotate_new(size());
+}
+
+// __swap_out_circular_buffer relocates the objects in [__begin_, __p) into the front of __v, the objects in
+// [__p, __end_) into the back of __v and swaps the buffers of *this and __v. It is assumed that __v provides space for
+// exactly (__p - __begin_) objects in the front and space for at least (__end_ - __p) objects in the back. This
+// function has a strong exception guarantee if __begin_ == __p || __end_ == __p.
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::pointer
+vector<_Tp, _Allocator>::__swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v, pointer __p) {
+ __annotate_delete();
+ pointer __ret = __v.__begin_;
+
+ // Relocate [__p, __end_) first to avoid having a hole in [__begin_, __end_)
+ // in case something in [__begin_, __p) throws.
+ std::__uninitialized_allocator_relocate(
+ __alloc(), std::__to_address(__p), std::__to_address(__end_), std::__to_address(__v.__end_));
+ __v.__end_ += (__end_ - __p);
+ __end_ = __p; // The objects in [__p, __end_) have been destroyed by relocating them.
+ auto __new_begin = __v.__begin_ - (__p - __begin_);
+
+ std::__uninitialized_allocator_relocate(
+ __alloc(), std::__to_address(__begin_), std::__to_address(__p), std::__to_address(__new_begin));
+ __v.__begin_ = __new_begin;
+ __end_ = __begin_; // All the objects have been destroyed by relocating them.
+
+ std::swap(this->__begin_, __v.__begin_);
+ std::swap(this->__end_, __v.__end_);
+ std::swap(this->__end_cap(), __v.__end_cap());
+ __v.__first_ = __v.__begin_;
+ __annotate_new(size());
+ return __ret;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::__vdeallocate() _NOEXCEPT {
+ if (this->__begin_ != nullptr) {
+ clear();
+ __annotate_delete();
+ __alloc_traits::deallocate(this->__alloc(), this->__begin_, capacity());
+ this->__begin_ = this->__end_ = this->__end_cap() = nullptr;
+ }
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::size_type
+vector<_Tp, _Allocator>::max_size() const _NOEXCEPT {
+ return std::min<size_type>(__alloc_traits::max_size(this->__alloc()), numeric_limits<difference_type>::max());
+}
+
+// Precondition: __new_size > capacity()
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::size_type
+vector<_Tp, _Allocator>::__recommend(size_type __new_size) const {
+ const size_type __ms = max_size();
+ if (__new_size > __ms)
+ this->__throw_length_error();
+ const size_type __cap = capacity();
+ if (__cap >= __ms / 2)
+ return __ms;
+ return std::max<size_type>(2 * __cap, __new_size);
+}
+
+// Default constructs __n objects starting at __end_
+// throws if construction throws
+// Precondition: __n > 0
+// Precondition: size() + __n <= capacity()
+// Postcondition: size() == size() + __n
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::__construct_at_end(size_type __n) {
+ _ConstructTransaction __tx(*this, __n);
+ const_pointer __new_end = __tx.__new_end_;
+ for (pointer __pos = __tx.__pos_; __pos != __new_end; __tx.__pos_ = ++__pos) {
+ __alloc_traits::construct(this->__alloc(), std::__to_address(__pos));
+ }
+}
+
+// Copy constructs __n objects starting at __end_ from __x
+// throws if construction throws
+// Precondition: __n > 0
+// Precondition: size() + __n <= capacity()
+// Postcondition: size() == old size() + __n
+// Postcondition: [i] == __x for all i in [size() - __n, __n)
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline void
+vector<_Tp, _Allocator>::__construct_at_end(size_type __n, const_reference __x) {
+ _ConstructTransaction __tx(*this, __n);
+ const_pointer __new_end = __tx.__new_end_;
+ for (pointer __pos = __tx.__pos_; __pos != __new_end; __tx.__pos_ = ++__pos) {
+ __alloc_traits::construct(this->__alloc(), std::__to_address(__pos), __x);
+ }
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+vector<_Tp, _Allocator>::__construct_at_end(_InputIterator __first, _Sentinel __last, size_type __n) {
+ _ConstructTransaction __tx(*this, __n);
+ __tx.__pos_ = std::__uninitialized_allocator_copy(__alloc(), __first, __last, __tx.__pos_);
+}
+
+// Default constructs __n objects starting at __end_
+// throws if construction throws
+// Postcondition: size() == size() + __n
+// Exception safety: strong.
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::__append(size_type __n) {
+ if (static_cast<size_type>(this->__end_cap() - this->__end_) >= __n)
+ this->__construct_at_end(__n);
+ else {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + __n), size(), __a);
+ __v.__construct_at_end(__n);
+ __swap_out_circular_buffer(__v);
+ }
+}
+
+// Default constructs __n objects starting at __end_
+// throws if construction throws
+// Postcondition: size() == size() + __n
+// Exception safety: strong.
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::__append(size_type __n, const_reference __x) {
+ if (static_cast<size_type>(this->__end_cap() - this->__end_) >= __n)
+ this->__construct_at_end(__n, __x);
+ else {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + __n), size(), __a);
+ __v.__construct_at_end(__n, __x);
+ __swap_out_circular_buffer(__v);
+ }
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIterator,
+ __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value &&
+ is_constructible<_Tp, typename iterator_traits<_InputIterator>::reference>::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<_Tp, _Allocator>::vector(_InputIterator __first, _InputIterator __last) {
+ __init_with_sentinel(__first, __last);
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIterator,
+ __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value &&
+ is_constructible<_Tp, typename iterator_traits<_InputIterator>::reference>::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+vector<_Tp, _Allocator>::vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a)
+ : __end_cap_(nullptr, __a) {
+ __init_with_sentinel(__first, __last);
+}
+
+template <class _Tp, class _Allocator>
+template <class _ForwardIterator,
+ __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value &&
+ is_constructible<_Tp, typename iterator_traits<_ForwardIterator>::reference>::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<_Tp, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last) {
+ size_type __n = static_cast<size_type>(std::distance(__first, __last));
+ __init_with_size(__first, __last, __n);
+}
+
+template <class _Tp, class _Allocator>
+template <class _ForwardIterator,
+ __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value &&
+ is_constructible<_Tp, typename iterator_traits<_ForwardIterator>::reference>::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+vector<_Tp, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a)
+ : __end_cap_(nullptr, __a) {
+ size_type __n = static_cast<size_type>(std::distance(__first, __last));
+ __init_with_size(__first, __last, __n);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<_Tp, _Allocator>::vector(const vector& __x)
+ : __end_cap_(nullptr, __alloc_traits::select_on_container_copy_construction(__x.__alloc())) {
+ __init_with_size(__x.__begin_, __x.__end_, __x.size());
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+vector<_Tp, _Allocator>::vector(const vector& __x, const __type_identity_t<allocator_type>& __a)
+ : __end_cap_(nullptr, __a) {
+ __init_with_size(__x.__begin_, __x.__end_, __x.size());
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI vector<_Tp, _Allocator>::vector(vector&& __x)
+#if _LIBCPP_STD_VER >= 17
+ noexcept
+#else
+ _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
+#endif
+ : __end_cap_(nullptr, std::move(__x.__alloc())) {
+ this->__begin_ = __x.__begin_;
+ this->__end_ = __x.__end_;
+ this->__end_cap() = __x.__end_cap();
+ __x.__begin_ = __x.__end_ = __x.__end_cap() = nullptr;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI
+vector<_Tp, _Allocator>::vector(vector&& __x, const __type_identity_t<allocator_type>& __a)
+ : __end_cap_(nullptr, __a) {
+ if (__a == __x.__alloc()) {
+ this->__begin_ = __x.__begin_;
+ this->__end_ = __x.__end_;
+ this->__end_cap() = __x.__end_cap();
+ __x.__begin_ = __x.__end_ = __x.__end_cap() = nullptr;
+ } else {
+ typedef move_iterator<iterator> _Ip;
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+ assign(_Ip(__x.begin()), _Ip(__x.end()));
+ __guard.__complete();
+ }
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI
+vector<_Tp, _Allocator>::vector(initializer_list<value_type> __il) {
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+ if (__il.size() > 0) {
+ __vallocate(__il.size());
+ __construct_at_end(__il.begin(), __il.end(), __il.size());
+ }
+ __guard.__complete();
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI
+vector<_Tp, _Allocator>::vector(initializer_list<value_type> __il, const allocator_type& __a)
+ : __end_cap_(nullptr, __a) {
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+ if (__il.size() > 0) {
+ __vallocate(__il.size());
+ __construct_at_end(__il.begin(), __il.end(), __il.size());
+ }
+ __guard.__complete();
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI vector<_Tp, _Allocator>&
+vector<_Tp, _Allocator>::operator=(vector&& __x)
+ _NOEXCEPT_(__noexcept_move_assign_container<_Allocator, __alloc_traits>::value) {
+ __move_assign(__x, integral_constant<bool, __alloc_traits::propagate_on_container_move_assignment::value>());
+ return *this;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::__move_assign(vector& __c, false_type)
+ _NOEXCEPT_(__alloc_traits::is_always_equal::value) {
+ if (__alloc() != __c.__alloc()) {
+ typedef move_iterator<iterator> _Ip;
+ assign(_Ip(__c.begin()), _Ip(__c.end()));
+ } else
+ __move_assign(__c, true_type());
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::__move_assign(vector& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
+ __vdeallocate();
+ __move_assign_alloc(__c); // this can throw
+ this->__begin_ = __c.__begin_;
+ this->__end_ = __c.__end_;
+ this->__end_cap() = __c.__end_cap();
+ __c.__begin_ = __c.__end_ = __c.__end_cap() = nullptr;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI vector<_Tp, _Allocator>&
+vector<_Tp, _Allocator>::operator=(const vector& __x) {
+ if (this != std::addressof(__x)) {
+ __copy_assign_alloc(__x);
+ assign(__x.__begin_, __x.__end_);
+ }
+ return *this;
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIterator,
+ __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value &&
+ is_constructible<_Tp, typename iterator_traits<_InputIterator>::reference>::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::assign(_InputIterator __first, _InputIterator __last) {
+ __assign_with_sentinel(__first, __last);
+}
+
+template <class _Tp, class _Allocator>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+vector<_Tp, _Allocator>::__assign_with_sentinel(_Iterator __first, _Sentinel __last) {
+ clear();
+ for (; __first != __last; ++__first)
+ emplace_back(*__first);
+}
+
+template <class _Tp, class _Allocator>
+template <class _ForwardIterator,
+ __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value &&
+ is_constructible<_Tp, typename iterator_traits<_ForwardIterator>::reference>::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::assign(_ForwardIterator __first, _ForwardIterator __last) {
+ __assign_with_size(__first, __last, std::distance(__first, __last));
+}
+
+template <class _Tp, class _Allocator>
+template <class _ForwardIterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+vector<_Tp, _Allocator>::__assign_with_size(_ForwardIterator __first, _Sentinel __last, difference_type __n) {
+ size_type __new_size = static_cast<size_type>(__n);
+ if (__new_size <= capacity()) {
+ if (__new_size > size()) {
+ _ForwardIterator __mid = std::next(__first, size());
+ std::copy(__first, __mid, this->__begin_);
+ __construct_at_end(__mid, __last, __new_size - size());
+ } else {
+ pointer __m = std::__copy<_ClassicAlgPolicy>(__first, __last, this->__begin_).second;
+ this->__destruct_at_end(__m);
+ }
+ } else {
+ __vdeallocate();
+ __vallocate(__recommend(__new_size));
+ __construct_at_end(__first, __last, __new_size);
+ }
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::assign(size_type __n, const_reference __u) {
+ if (__n <= capacity()) {
+ size_type __s = size();
+ std::fill_n(this->__begin_, std::min(__n, __s), __u);
+ if (__n > __s)
+ __construct_at_end(__n - __s, __u);
+ else
+ this->__destruct_at_end(this->__begin_ + __n);
+ } else {
+ __vdeallocate();
+ __vallocate(__recommend(static_cast<size_type>(__n)));
+ __construct_at_end(__n, __u);
+ }
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::begin() _NOEXCEPT {
+ return __make_iter(this->__begin_);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::const_iterator
+vector<_Tp, _Allocator>::begin() const _NOEXCEPT {
+ return __make_iter(this->__begin_);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::end() _NOEXCEPT {
+ return __make_iter(this->__end_);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::const_iterator
+vector<_Tp, _Allocator>::end() const _NOEXCEPT {
+ return __make_iter(this->__end_);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::reference
+vector<_Tp, _Allocator>::operator[](size_type __n) _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < size(), "vector[] index out of bounds");
+ return this->__begin_[__n];
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::const_reference
+vector<_Tp, _Allocator>::operator[](size_type __n) const _NOEXCEPT {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < size(), "vector[] index out of bounds");
+ return this->__begin_[__n];
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::reference vector<_Tp, _Allocator>::at(size_type __n) {
+ if (__n >= size())
+ this->__throw_out_of_range();
+ return this->__begin_[__n];
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::const_reference
+vector<_Tp, _Allocator>::at(size_type __n) const {
+ if (__n >= size())
+ this->__throw_out_of_range();
+ return this->__begin_[__n];
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::reserve(size_type __n) {
+ if (__n > capacity()) {
+ if (__n > max_size())
+ this->__throw_length_error();
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__n, size(), __a);
+ __swap_out_circular_buffer(__v);
+ }
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT {
+ if (capacity() > size()) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(size(), size(), __a);
+ // The Standard mandates shrink_to_fit() does not increase the capacity.
+ // With equal capacity keep the existing buffer. This avoids extra work
+ // due to swapping the elements.
+ if (__v.capacity() < capacity())
+ __swap_out_circular_buffer(__v);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Tp, class _Allocator>
+template <class _Up>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::pointer
+vector<_Tp, _Allocator>::__push_back_slow_path(_Up&& __x) {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), size(), __a);
+ // __v.push_back(std::forward<_Up>(__x));
+ __alloc_traits::construct(__a, std::__to_address(__v.__end_), std::forward<_Up>(__x));
+ __v.__end_++;
+ __swap_out_circular_buffer(__v);
+ return this->__end_;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
+vector<_Tp, _Allocator>::push_back(const_reference __x) {
+ pointer __end = this->__end_;
+ if (__end < this->__end_cap()) {
+ __construct_one_at_end(__x);
+ ++__end;
+ } else {
+ __end = __push_back_slow_path(__x);
+ }
+ this->__end_ = __end;
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void vector<_Tp, _Allocator>::push_back(value_type&& __x) {
+ pointer __end = this->__end_;
+ if (__end < this->__end_cap()) {
+ __construct_one_at_end(std::move(__x));
+ ++__end;
+ } else {
+ __end = __push_back_slow_path(std::move(__x));
+ }
+ this->__end_ = __end;
+}
+
+template <class _Tp, class _Allocator>
+template <class... _Args>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::pointer
+vector<_Tp, _Allocator>::__emplace_back_slow_path(_Args&&... __args) {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), size(), __a);
+ // __v.emplace_back(std::forward<_Args>(__args)...);
+ __alloc_traits::construct(__a, std::__to_address(__v.__end_), std::forward<_Args>(__args)...);
+ __v.__end_++;
+ __swap_out_circular_buffer(__v);
+ return this->__end_;
+}
+
+template <class _Tp, class _Allocator>
+template <class... _Args>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline
+#if _LIBCPP_STD_VER >= 17
+ typename vector<_Tp, _Allocator>::reference
+#else
+ void
+#endif
+ vector<_Tp, _Allocator>::emplace_back(_Args&&... __args) {
+ pointer __end = this->__end_;
+ if (__end < this->__end_cap()) {
+ __construct_one_at_end(std::forward<_Args>(__args)...);
+ ++__end;
+ } else {
+ __end = __emplace_back_slow_path(std::forward<_Args>(__args)...);
+ }
+ this->__end_ = __end;
+#if _LIBCPP_STD_VER >= 17
+ return *(__end - 1);
+#endif
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline void vector<_Tp, _Allocator>::pop_back() {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "vector::pop_back called on an empty vector");
+ this->__destruct_at_end(this->__end_ - 1);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::erase(const_iterator __position) {
+ _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+ __position != end(), "vector::erase(iterator) called with a non-dereferenceable iterator");
+ difference_type __ps = __position - cbegin();
+ pointer __p = this->__begin_ + __ps;
+ this->__destruct_at_end(std::move(__p + 1, this->__end_, __p));
+ return __make_iter(__p);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::erase(const_iterator __first, const_iterator __last) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__first <= __last, "vector::erase(first, last) called with invalid range");
+ pointer __p = this->__begin_ + (__first - begin());
+ if (__first != __last) {
+ this->__destruct_at_end(std::move(__p + (__last - __first), this->__end_, __p));
+ }
+ return __make_iter(__p);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+vector<_Tp, _Allocator>::__move_range(pointer __from_s, pointer __from_e, pointer __to) {
+ pointer __old_last = this->__end_;
+ difference_type __n = __old_last - __to;
+ {
+ pointer __i = __from_s + __n;
+ _ConstructTransaction __tx(*this, __from_e - __i);
+ for (pointer __pos = __tx.__pos_; __i < __from_e; ++__i, (void)++__pos, __tx.__pos_ = __pos) {
+ __alloc_traits::construct(this->__alloc(), std::__to_address(__pos), std::move(*__i));
+ }
+ }
+ std::move_backward(__from_s, __from_s + __n, __old_last);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::insert(const_iterator __position, const_reference __x) {
+ pointer __p = this->__begin_ + (__position - begin());
+ if (this->__end_ < this->__end_cap()) {
+ if (__p == this->__end_) {
+ __construct_one_at_end(__x);
+ } else {
+ __move_range(__p, this->__end_, __p + 1);
+ const_pointer __xr = pointer_traits<const_pointer>::pointer_to(__x);
+ if (std::__is_pointer_in_range(std::__to_address(__p), std::__to_address(__end_), std::addressof(__x)))
+ ++__xr;
+ *__p = *__xr;
+ }
+ } else {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), __p - this->__begin_, __a);
+ __v.push_back(__x);
+ __p = __swap_out_circular_buffer(__v, __p);
+ }
+ return __make_iter(__p);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::insert(const_iterator __position, value_type&& __x) {
+ pointer __p = this->__begin_ + (__position - begin());
+ if (this->__end_ < this->__end_cap()) {
+ if (__p == this->__end_) {
+ __construct_one_at_end(std::move(__x));
+ } else {
+ __move_range(__p, this->__end_, __p + 1);
+ *__p = std::move(__x);
+ }
+ } else {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), __p - this->__begin_, __a);
+ __v.push_back(std::move(__x));
+ __p = __swap_out_circular_buffer(__v, __p);
+ }
+ return __make_iter(__p);
+}
+
+template <class _Tp, class _Allocator>
+template <class... _Args>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::emplace(const_iterator __position, _Args&&... __args) {
+ pointer __p = this->__begin_ + (__position - begin());
+ if (this->__end_ < this->__end_cap()) {
+ if (__p == this->__end_) {
+ __construct_one_at_end(std::forward<_Args>(__args)...);
+ } else {
+ __temp_value<value_type, _Allocator> __tmp(this->__alloc(), std::forward<_Args>(__args)...);
+ __move_range(__p, this->__end_, __p + 1);
+ *__p = std::move(__tmp.get());
+ }
+ } else {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), __p - this->__begin_, __a);
+ __v.emplace_back(std::forward<_Args>(__args)...);
+ __p = __swap_out_circular_buffer(__v, __p);
+ }
+ return __make_iter(__p);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::insert(const_iterator __position, size_type __n, const_reference __x) {
+ pointer __p = this->__begin_ + (__position - begin());
+ if (__n > 0) {
+ // We can't compare unrelated pointers inside constant expressions
+ if (!__libcpp_is_constant_evaluated() && __n <= static_cast<size_type>(this->__end_cap() - this->__end_)) {
+ size_type __old_n = __n;
+ pointer __old_last = this->__end_;
+ if (__n > static_cast<size_type>(this->__end_ - __p)) {
+ size_type __cx = __n - (this->__end_ - __p);
+ __construct_at_end(__cx, __x);
+ __n -= __cx;
+ }
+ if (__n > 0) {
+ __move_range(__p, __old_last, __p + __old_n);
+ const_pointer __xr = pointer_traits<const_pointer>::pointer_to(__x);
+ if (__p <= __xr && __xr < this->__end_)
+ __xr += __old_n;
+ std::fill_n(__p, __n, *__xr);
+ }
+ } else {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + __n), __p - this->__begin_, __a);
+ __v.__construct_at_end(__n, __x);
+ __p = __swap_out_circular_buffer(__v, __p);
+ }
+ }
+ return __make_iter(__p);
+}
+template <class _Tp, class _Allocator>
+template <class _InputIterator,
+ __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value &&
+ is_constructible<_Tp, typename iterator_traits<_InputIterator>::reference>::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::insert(const_iterator __position, _InputIterator __first, _InputIterator __last) {
+ return __insert_with_sentinel(__position, __first, __last);
+}
+
+template <class _Tp, class _Allocator>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::__insert_with_sentinel(const_iterator __position, _InputIterator __first, _Sentinel __last) {
+ difference_type __off = __position - begin();
+ pointer __p = this->__begin_ + __off;
+ allocator_type& __a = this->__alloc();
+ pointer __old_last = this->__end_;
+ for (; this->__end_ != this->__end_cap() && __first != __last; ++__first) {
+ __construct_one_at_end(*__first);
+ }
+ __split_buffer<value_type, allocator_type&> __v(__a);
+ if (__first != __last) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __v.__construct_at_end_with_sentinel(std::move(__first), std::move(__last));
+ difference_type __old_size = __old_last - this->__begin_;
+ difference_type __old_p = __p - this->__begin_;
+ reserve(__recommend(size() + __v.size()));
+ __p = this->__begin_ + __old_p;
+ __old_last = this->__begin_ + __old_size;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ erase(__make_iter(__old_last), end());
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+ __p = std::rotate(__p, __old_last, this->__end_);
+ insert(__make_iter(__p), std::make_move_iterator(__v.begin()), std::make_move_iterator(__v.end()));
+ return begin() + __off;
+}
+
+template <class _Tp, class _Allocator>
+template <class _ForwardIterator,
+ __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value &&
+ is_constructible<_Tp, typename iterator_traits<_ForwardIterator>::reference>::value,
+ int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::insert(const_iterator __position, _ForwardIterator __first, _ForwardIterator __last) {
+ return __insert_with_size(__position, __first, __last, std::distance(__first, __last));
+}
+
+template <class _Tp, class _Allocator>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::iterator
+vector<_Tp, _Allocator>::__insert_with_size(
+ const_iterator __position, _Iterator __first, _Sentinel __last, difference_type __n) {
+ auto __insertion_size = __n;
+ pointer __p = this->__begin_ + (__position - begin());
+ if (__n > 0) {
+ if (__n <= this->__end_cap() - this->__end_) {
+ size_type __old_n = __n;
+ pointer __old_last = this->__end_;
+ _Iterator __m = std::next(__first, __n);
+ difference_type __dx = this->__end_ - __p;
+ if (__n > __dx) {
+ __m = __first;
+ difference_type __diff = this->__end_ - __p;
+ std::advance(__m, __diff);
+ __construct_at_end(__m, __last, __n - __diff);
+ __n = __dx;
+ }
+ if (__n > 0) {
+ __move_range(__p, __old_last, __p + __old_n);
+ std::copy(__first, __m, __p);
+ }
+ } else {
+ allocator_type& __a = this->__alloc();
+ __split_buffer<value_type, allocator_type&> __v(__recommend(size() + __n), __p - this->__begin_, __a);
+ __v.__construct_at_end_with_size(__first, __insertion_size);
+ __p = __swap_out_circular_buffer(__v, __p);
+ }
+ }
+ return __make_iter(__p);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::resize(size_type __sz) {
+ size_type __cs = size();
+ if (__cs < __sz)
+ this->__append(__sz - __cs);
+ else if (__cs > __sz)
+ this->__destruct_at_end(this->__begin_ + __sz);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::resize(size_type __sz, const_reference __x) {
+ size_type __cs = size();
+ if (__cs < __sz)
+ this->__append(__sz - __cs, __x);
+ else if (__cs > __sz)
+ this->__destruct_at_end(this->__begin_ + __sz);
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::swap(vector& __x)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>)
+#endif
+{
+ _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
+ __alloc_traits::propagate_on_container_swap::value || this->__alloc() == __x.__alloc(),
+ "vector::swap: Either propagate_on_container_swap must be true"
+ " or the allocators must compare equal");
+ std::swap(this->__begin_, __x.__begin_);
+ std::swap(this->__end_, __x.__end_);
+ std::swap(this->__end_cap(), __x.__end_cap());
+ std::__swap_allocator(
+ this->__alloc(), __x.__alloc(), integral_constant<bool, __alloc_traits::propagate_on_container_swap::value>());
+}
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 bool vector<_Tp, _Allocator>::__invariants() const {
+ if (this->__begin_ == nullptr) {
+ if (this->__end_ != nullptr || this->__end_cap() != nullptr)
+ return false;
+ } else {
+ if (this->__begin_ > this->__end_)
+ return false;
+ if (this->__begin_ == this->__end_cap())
+ return false;
+ if (this->__end_ > this->__end_cap())
+ return false;
+ }
+ return true;
+}
+
+// vector<bool>
+
+template <class _Allocator>
+class vector<bool, _Allocator>;
+
+template <class _Allocator>
+struct hash<vector<bool, _Allocator> >;
+
+template <class _Allocator>
+struct __has_storage_type<vector<bool, _Allocator> > {
+ static const bool value = true;
+};
+
+template <class _Allocator>
+class _LIBCPP_TEMPLATE_VIS vector<bool, _Allocator> {
+public:
+ typedef vector __self;
+ typedef bool value_type;
+ typedef _Allocator allocator_type;
+ typedef allocator_traits<allocator_type> __alloc_traits;
+ typedef typename __alloc_traits::size_type size_type;
+ typedef typename __alloc_traits::difference_type difference_type;
+ typedef size_type __storage_type;
+ typedef __bit_iterator<vector, false> pointer;
+ typedef __bit_iterator<vector, true> const_pointer;
+ typedef pointer iterator;
+ typedef const_pointer const_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+
+private:
+ typedef __rebind_alloc<__alloc_traits, __storage_type> __storage_allocator;
+ typedef allocator_traits<__storage_allocator> __storage_traits;
+ typedef typename __storage_traits::pointer __storage_pointer;
+ typedef typename __storage_traits::const_pointer __const_storage_pointer;
+
+ __storage_pointer __begin_;
+ size_type __size_;
+ __compressed_pair<size_type, __storage_allocator> __cap_alloc_;
+
+public:
+ typedef __bit_reference<vector> reference;
+#ifdef _LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL
+ using const_reference = bool;
+#else
+ typedef __bit_const_reference<vector> const_reference;
+#endif
+
+private:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type& __cap() _NOEXCEPT { return __cap_alloc_.first(); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const size_type& __cap() const _NOEXCEPT {
+ return __cap_alloc_.first();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __storage_allocator& __alloc() _NOEXCEPT {
+ return __cap_alloc_.second();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const __storage_allocator& __alloc() const _NOEXCEPT {
+ return __cap_alloc_.second();
+ }
+
+ static const unsigned __bits_per_word = static_cast<unsigned>(sizeof(__storage_type) * CHAR_BIT);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static size_type
+ __internal_cap_to_external(size_type __n) _NOEXCEPT {
+ return __n * __bits_per_word;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static size_type
+ __external_cap_to_internal(size_type __n) _NOEXCEPT {
+ return (__n - 1) / __bits_per_word + 1;
+ }
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector()
+ _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit vector(const allocator_type& __a)
+#if _LIBCPP_STD_VER <= 14
+ _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value);
+#else
+ _NOEXCEPT;
+#endif
+
+private:
+ class __destroy_vector {
+ public:
+ _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI __destroy_vector(vector& __vec) : __vec_(__vec) {}
+
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void operator()() {
+ if (__vec_.__begin_ != nullptr)
+ __storage_traits::deallocate(__vec_.__alloc(), __vec_.__begin_, __vec_.__cap());
+ }
+
+ private:
+ vector& __vec_;
+ };
+
+public:
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~vector() { __destroy_vector (*this)(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit vector(size_type __n);
+#if _LIBCPP_STD_VER >= 14
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit vector(size_type __n, const allocator_type& __a);
+#endif
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(size_type __n, const value_type& __v);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ vector(size_type __n, const value_type& __v, const allocator_type& __a);
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(_InputIterator __first, _InputIterator __last);
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a);
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(_ForwardIterator __first, _ForwardIterator __last);
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<bool> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr vector(from_range_t, _Range&& __range, const allocator_type& __a = allocator_type())
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, static_cast<__storage_allocator>(__a)) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ __init_with_size(ranges::begin(__range), ranges::end(__range), __n);
+
+ } else {
+ __init_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(const vector& __v);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(const vector& __v, const allocator_type& __a);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector& operator=(const vector& __v);
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(initializer_list<value_type> __il);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ vector(initializer_list<value_type> __il, const allocator_type& __a);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector& operator=(initializer_list<value_type> __il) {
+ assign(__il.begin(), __il.end());
+ return *this;
+ }
+
+#endif // !_LIBCPP_CXX03_LANG
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(vector&& __v)
+#if _LIBCPP_STD_VER >= 17
+ noexcept;
+#else
+ _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
+#endif
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ vector(vector&& __v, const __type_identity_t<allocator_type>& __a);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector& operator=(vector&& __v)
+ _NOEXCEPT_(__noexcept_move_assign_container<_Allocator, __alloc_traits>::value);
+
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 assign(_InputIterator __first, _InputIterator __last);
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ void _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 assign(_ForwardIterator __first, _ForwardIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<bool> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr void assign_range(_Range&& __range) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ __assign_with_size(ranges::begin(__range), ranges::end(__range), __n);
+
+ } else {
+ __assign_with_sentinel(ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void assign(size_type __n, const value_type& __x);
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void assign(initializer_list<value_type> __il) {
+ assign(__il.begin(), __il.end());
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 allocator_type get_allocator() const _NOEXCEPT {
+ return allocator_type(this->__alloc());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type max_size() const _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type capacity() const _NOEXCEPT {
+ return __internal_cap_to_external(__cap());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type size() const _NOEXCEPT { return __size_; }
+ _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool empty() const _NOEXCEPT {
+ return __size_ == 0;
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void reserve(size_type __n);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void shrink_to_fit() _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator begin() _NOEXCEPT { return __make_iter(0); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator begin() const _NOEXCEPT { return __make_iter(0); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator end() _NOEXCEPT { return __make_iter(__size_); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator end() const _NOEXCEPT {
+ return __make_iter(__size_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reverse_iterator rbegin() _NOEXCEPT {
+ return reverse_iterator(end());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reverse_iterator rbegin() const _NOEXCEPT {
+ return const_reverse_iterator(end());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reverse_iterator rend() _NOEXCEPT {
+ return reverse_iterator(begin());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reverse_iterator rend() const _NOEXCEPT {
+ return const_reverse_iterator(begin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator cbegin() const _NOEXCEPT { return __make_iter(0); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator cend() const _NOEXCEPT {
+ return __make_iter(__size_);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reverse_iterator crbegin() const _NOEXCEPT {
+ return rbegin();
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference operator[](size_type __n) { return __make_ref(__n); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference operator[](size_type __n) const {
+ return __make_ref(__n);
+ }
+ _LIBCPP_HIDE_FROM_ABI reference at(size_type __n);
+ _LIBCPP_HIDE_FROM_ABI const_reference at(size_type __n) const;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference front() { return __make_ref(0); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference front() const { return __make_ref(0); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference back() { return __make_ref(__size_ - 1); }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference back() const { return __make_ref(__size_ - 1); }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void push_back(const value_type& __x);
+#if _LIBCPP_STD_VER >= 14
+ template <class... _Args>
+# if _LIBCPP_STD_VER >= 17
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference emplace_back(_Args&&... __args)
+# else
+ _LIBCPP_HIDE_FROM_ABI void emplace_back(_Args&&... __args)
+# endif
+ {
+ push_back(value_type(std::forward<_Args>(__args)...));
+# if _LIBCPP_STD_VER >= 17
+ return this->back();
+# endif
+ }
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<bool> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr void append_range(_Range&& __range) {
+ insert_range(end(), std::forward<_Range>(__range));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void pop_back() { --__size_; }
+
+#if _LIBCPP_STD_VER >= 14
+ template <class... _Args>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator emplace(const_iterator __position, _Args&&... __args) {
+ return insert(__position, value_type(std::forward<_Args>(__args)...));
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator insert(const_iterator __position, const value_type& __x);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
+ insert(const_iterator __position, size_type __n, const value_type& __x);
+ template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
+ iterator _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ insert(const_iterator __position, _InputIterator __first, _InputIterator __last);
+ template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
+ iterator _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+ insert(const_iterator __position, _ForwardIterator __first, _ForwardIterator __last);
+
+#if _LIBCPP_STD_VER >= 23
+ template <_ContainerCompatibleRange<bool> _Range>
+ _LIBCPP_HIDE_FROM_ABI constexpr iterator insert_range(const_iterator __position, _Range&& __range) {
+ if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
+ auto __n = static_cast<size_type>(ranges::distance(__range));
+ return __insert_with_size(__position, ranges::begin(__range), ranges::end(__range), __n);
+
+ } else {
+ return __insert_with_sentinel(__position, ranges::begin(__range), ranges::end(__range));
+ }
+ }
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
+ insert(const_iterator __position, initializer_list<value_type> __il) {
+ return insert(__position, __il.begin(), __il.end());
+ }
+#endif
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator erase(const_iterator __position);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator erase(const_iterator __first, const_iterator __last);
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void clear() _NOEXCEPT { __size_ = 0; }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(vector&)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT;
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>);
+#endif
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static void swap(reference __x, reference __y) _NOEXCEPT {
+ std::swap(__x, __y);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void resize(size_type __sz, value_type __x = false);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void flip() _NOEXCEPT;
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __invariants() const;
+
+private:
+ _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI void __throw_length_error() const { std::__throw_length_error("vector"); }
+
+ _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI void __throw_out_of_range() const { std::__throw_out_of_range("vector"); }
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ __init_with_size(_InputIterator __first, _Sentinel __last, size_type __n) {
+ auto __guard = std::__make_exception_guard(__destroy_vector(*this));
+
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(std::move(__first), std::move(__last), __n);
+ }
+
+ __guard.__complete();
+ }
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ __init_with_sentinel(_InputIterator __first, _Sentinel __last) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ for (; __first != __last; ++__first)
+ push_back(*__first);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ if (__begin_ != nullptr)
+ __storage_traits::deallocate(__alloc(), __begin_, __cap());
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __assign_with_sentinel(_Iterator __first, _Sentinel __last);
+
+ template <class _ForwardIterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+ __assign_with_size(_ForwardIterator __first, _Sentinel __last, difference_type __ns);
+
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
+ __insert_with_sentinel(const_iterator __position, _InputIterator __first, _Sentinel __last);
+
+ template <class _Iterator, class _Sentinel>
+ _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
+ __insert_with_size(const_iterator __position, _Iterator __first, _Sentinel __last, difference_type __n);
+
+ // Allocate space for __n objects
+ // throws length_error if __n > max_size()
+ // throws (probably bad_alloc) if memory run out
+ // Precondition: __begin_ == __end_ == __cap() == 0
+ // Precondition: __n > 0
+ // Postcondition: capacity() >= __n
+ // Postcondition: size() == 0
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __vallocate(size_type __n) {
+ if (__n > max_size())
+ __throw_length_error();
+ auto __allocation = std::__allocate_at_least(__alloc(), __external_cap_to_internal(__n));
+ __begin_ = __allocation.ptr;
+ __size_ = 0;
+ __cap() = __allocation.count;
+ if (__libcpp_is_constant_evaluated()) {
+ for (size_type __i = 0; __i != __cap(); ++__i)
+ std::__construct_at(std::__to_address(__begin_) + __i);
+ }
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __vdeallocate() _NOEXCEPT;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static size_type __align_it(size_type __new_size) _NOEXCEPT {
+ return (__new_size + (__bits_per_word - 1)) & ~((size_type)__bits_per_word - 1);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type __recommend(size_type __new_size) const;
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __construct_at_end(size_type __n, bool __x);
+ template <class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+ __construct_at_end(_InputIterator __first, _Sentinel __last, size_type __n);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __append(size_type __n, const_reference __x);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference __make_ref(size_type __pos) _NOEXCEPT {
+ return reference(__begin_ + __pos / __bits_per_word, __storage_type(1) << __pos % __bits_per_word);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference __make_ref(size_type __pos) const _NOEXCEPT {
+ return __bit_const_reference<vector>(
+ __begin_ + __pos / __bits_per_word, __storage_type(1) << __pos % __bits_per_word);
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator __make_iter(size_type __pos) _NOEXCEPT {
+ return iterator(__begin_ + __pos / __bits_per_word, static_cast<unsigned>(__pos % __bits_per_word));
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator __make_iter(size_type __pos) const _NOEXCEPT {
+ return const_iterator(__begin_ + __pos / __bits_per_word, static_cast<unsigned>(__pos % __bits_per_word));
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator __const_iterator_cast(const_iterator __p) _NOEXCEPT {
+ return begin() + (__p - cbegin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __copy_assign_alloc(const vector& __v) {
+ __copy_assign_alloc(
+ __v, integral_constant<bool, __storage_traits::propagate_on_container_copy_assignment::value>());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __copy_assign_alloc(const vector& __c, true_type) {
+ if (__alloc() != __c.__alloc())
+ __vdeallocate();
+ __alloc() = __c.__alloc();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __copy_assign_alloc(const vector&, false_type) {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign(vector& __c, false_type);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign(vector& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign_alloc(vector& __c)
+ _NOEXCEPT_(!__storage_traits::propagate_on_container_move_assignment::value ||
+ is_nothrow_move_assignable<allocator_type>::value) {
+ __move_assign_alloc(
+ __c, integral_constant<bool, __storage_traits::propagate_on_container_move_assignment::value>());
+ }
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign_alloc(vector& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
+ __alloc() = std::move(__c.__alloc());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign_alloc(vector&, false_type) _NOEXCEPT {}
+
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_t __hash_code() const _NOEXCEPT;
+
+ friend class __bit_reference<vector>;
+ friend class __bit_const_reference<vector>;
+ friend class __bit_iterator<vector, false>;
+ friend class __bit_iterator<vector, true>;
+ friend struct __bit_array<vector>;
+ friend struct _LIBCPP_TEMPLATE_VIS hash<vector>;
+};
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::__vdeallocate() _NOEXCEPT {
+ if (this->__begin_ != nullptr) {
+ __storage_traits::deallocate(this->__alloc(), this->__begin_, __cap());
+ this->__begin_ = nullptr;
+ this->__size_ = this->__cap() = 0;
+ }
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::size_type
+vector<bool, _Allocator>::max_size() const _NOEXCEPT {
+ size_type __amax = __storage_traits::max_size(__alloc());
+ size_type __nmax = numeric_limits<size_type>::max() / 2; // end() >= begin(), always
+ if (__nmax / __bits_per_word <= __amax)
+ return __nmax;
+ return __internal_cap_to_external(__amax);
+}
+
+// Precondition: __new_size > capacity()
+template <class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::size_type
+vector<bool, _Allocator>::__recommend(size_type __new_size) const {
+ const size_type __ms = max_size();
+ if (__new_size > __ms)
+ this->__throw_length_error();
+ const size_type __cap = capacity();
+ if (__cap >= __ms / 2)
+ return __ms;
+ return std::max(2 * __cap, __align_it(__new_size));
+}
+
+// Default constructs __n objects starting at __end_
+// Precondition: __n > 0
+// Precondition: size() + __n <= capacity()
+// Postcondition: size() == size() + __n
+template <class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
+vector<bool, _Allocator>::__construct_at_end(size_type __n, bool __x) {
+ size_type __old_size = this->__size_;
+ this->__size_ += __n;
+ if (__old_size == 0 || ((__old_size - 1) / __bits_per_word) != ((this->__size_ - 1) / __bits_per_word)) {
+ if (this->__size_ <= __bits_per_word)
+ this->__begin_[0] = __storage_type(0);
+ else
+ this->__begin_[(this->__size_ - 1) / __bits_per_word] = __storage_type(0);
+ }
+ std::fill_n(__make_iter(__old_size), __n, __x);
+}
+
+template <class _Allocator>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void
+vector<bool, _Allocator>::__construct_at_end(_InputIterator __first, _Sentinel __last, size_type __n) {
+ size_type __old_size = this->__size_;
+ this->__size_ += __n;
+ if (__old_size == 0 || ((__old_size - 1) / __bits_per_word) != ((this->__size_ - 1) / __bits_per_word)) {
+ if (this->__size_ <= __bits_per_word)
+ this->__begin_[0] = __storage_type(0);
+ else
+ this->__begin_[(this->__size_ - 1) / __bits_per_word] = __storage_type(0);
+ }
+ std::__copy<_ClassicAlgPolicy>(__first, __last, __make_iter(__old_size));
+}
+
+template <class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector()
+ _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, __default_init_tag()) {}
+
+template <class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(const allocator_type& __a)
+#if _LIBCPP_STD_VER <= 14
+ _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
+#else
+ _NOEXCEPT
+#endif
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, static_cast<__storage_allocator>(__a)) {
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(size_type __n)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, __default_init_tag()) {
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__n, false);
+ }
+}
+
+#if _LIBCPP_STD_VER >= 14
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(size_type __n, const allocator_type& __a)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, static_cast<__storage_allocator>(__a)) {
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__n, false);
+ }
+}
+#endif
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(size_type __n, const value_type& __x)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, __default_init_tag()) {
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__n, __x);
+ }
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+vector<bool, _Allocator>::vector(size_type __n, const value_type& __x, const allocator_type& __a)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, static_cast<__storage_allocator>(__a)) {
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__n, __x);
+ }
+}
+
+template <class _Allocator>
+template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(_InputIterator __first, _InputIterator __last)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, __default_init_tag()) {
+ __init_with_sentinel(__first, __last);
+}
+
+template <class _Allocator>
+template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+vector<bool, _Allocator>::vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, static_cast<__storage_allocator>(__a)) {
+ __init_with_sentinel(__first, __last);
+}
+
+template <class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, __default_init_tag()) {
+ auto __n = static_cast<size_type>(std::distance(__first, __last));
+ __init_with_size(__first, __last, __n);
+}
+
+template <class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+vector<bool, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, static_cast<__storage_allocator>(__a)) {
+ auto __n = static_cast<size_type>(std::distance(__first, __last));
+ __init_with_size(__first, __last, __n);
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(initializer_list<value_type> __il)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, __default_init_tag()) {
+ size_type __n = static_cast<size_type>(__il.size());
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__il.begin(), __il.end(), __n);
+ }
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+vector<bool, _Allocator>::vector(initializer_list<value_type> __il, const allocator_type& __a)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, static_cast<__storage_allocator>(__a)) {
+ size_type __n = static_cast<size_type>(__il.size());
+ if (__n > 0) {
+ __vallocate(__n);
+ __construct_at_end(__il.begin(), __il.end(), __n);
+ }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(const vector& __v)
+ : __begin_(nullptr),
+ __size_(0),
+ __cap_alloc_(0, __storage_traits::select_on_container_copy_construction(__v.__alloc())) {
+ if (__v.size() > 0) {
+ __vallocate(__v.size());
+ __construct_at_end(__v.begin(), __v.end(), __v.size());
+ }
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(const vector& __v, const allocator_type& __a)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, __a) {
+ if (__v.size() > 0) {
+ __vallocate(__v.size());
+ __construct_at_end(__v.begin(), __v.end(), __v.size());
+ }
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>& vector<bool, _Allocator>::operator=(const vector& __v) {
+ if (this != std::addressof(__v)) {
+ __copy_assign_alloc(__v);
+ if (__v.__size_) {
+ if (__v.__size_ > capacity()) {
+ __vdeallocate();
+ __vallocate(__v.__size_);
+ }
+ std::copy(__v.__begin_, __v.__begin_ + __external_cap_to_internal(__v.__size_), __begin_);
+ }
+ __size_ = __v.__size_;
+ }
+ return *this;
+}
+
+template <class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(vector&& __v)
+#if _LIBCPP_STD_VER >= 17
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
+#endif
+ : __begin_(__v.__begin_),
+ __size_(__v.__size_),
+ __cap_alloc_(std::move(__v.__cap_alloc_)) {
+ __v.__begin_ = nullptr;
+ __v.__size_ = 0;
+ __v.__cap() = 0;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20
+vector<bool, _Allocator>::vector(vector&& __v, const __type_identity_t<allocator_type>& __a)
+ : __begin_(nullptr), __size_(0), __cap_alloc_(0, __a) {
+ if (__a == allocator_type(__v.__alloc())) {
+ this->__begin_ = __v.__begin_;
+ this->__size_ = __v.__size_;
+ this->__cap() = __v.__cap();
+ __v.__begin_ = nullptr;
+ __v.__cap() = __v.__size_ = 0;
+ } else if (__v.size() > 0) {
+ __vallocate(__v.size());
+ __construct_at_end(__v.begin(), __v.end(), __v.size());
+ }
+}
+
+template <class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>&
+vector<bool, _Allocator>::operator=(vector&& __v)
+ _NOEXCEPT_(__noexcept_move_assign_container<_Allocator, __alloc_traits>::value) {
+ __move_assign(__v, integral_constant<bool, __storage_traits::propagate_on_container_move_assignment::value>());
+ return *this;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::__move_assign(vector& __c, false_type) {
+ if (__alloc() != __c.__alloc())
+ assign(__c.begin(), __c.end());
+ else
+ __move_assign(__c, true_type());
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::__move_assign(vector& __c, true_type)
+ _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
+ __vdeallocate();
+ __move_assign_alloc(__c);
+ this->__begin_ = __c.__begin_;
+ this->__size_ = __c.__size_;
+ this->__cap() = __c.__cap();
+ __c.__begin_ = nullptr;
+ __c.__cap() = __c.__size_ = 0;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::assign(size_type __n, const value_type& __x) {
+ __size_ = 0;
+ if (__n > 0) {
+ size_type __c = capacity();
+ if (__n <= __c)
+ __size_ = __n;
+ else {
+ vector __v(get_allocator());
+ __v.reserve(__recommend(__n));
+ __v.__size_ = __n;
+ swap(__v);
+ }
+ std::fill_n(begin(), __n, __x);
+ }
+}
+
+template <class _Allocator>
+template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::assign(_InputIterator __first, _InputIterator __last) {
+ __assign_with_sentinel(__first, __last);
+}
+
+template <class _Allocator>
+template <class _Iterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+vector<bool, _Allocator>::__assign_with_sentinel(_Iterator __first, _Sentinel __last) {
+ clear();
+ for (; __first != __last; ++__first)
+ push_back(*__first);
+}
+
+template <class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::assign(_ForwardIterator __first, _ForwardIterator __last) {
+ __assign_with_size(__first, __last, std::distance(__first, __last));
+}
+
+template <class _Allocator>
+template <class _ForwardIterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+vector<bool, _Allocator>::__assign_with_size(_ForwardIterator __first, _Sentinel __last, difference_type __ns) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__ns >= 0, "invalid range specified");
+
+ clear();
+
+ const size_t __n = static_cast<size_type>(__ns);
+ if (__n) {
+ if (__n > capacity()) {
+ __vdeallocate();
+ __vallocate(__n);
+ }
+ __construct_at_end(__first, __last, __n);
+ }
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::reserve(size_type __n) {
+ if (__n > capacity()) {
+ if (__n > max_size())
+ this->__throw_length_error();
+ vector __v(this->get_allocator());
+ __v.__vallocate(__n);
+ __v.__construct_at_end(this->begin(), this->end(), this->size());
+ swap(__v);
+ }
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::shrink_to_fit() _NOEXCEPT {
+ if (__external_cap_to_internal(size()) > __cap()) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ vector(*this, allocator_type(__alloc())).swap(*this);
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+}
+
+template <class _Allocator>
+typename vector<bool, _Allocator>::reference vector<bool, _Allocator>::at(size_type __n) {
+ if (__n >= size())
+ this->__throw_out_of_range();
+ return (*this)[__n];
+}
+
+template <class _Allocator>
+typename vector<bool, _Allocator>::const_reference vector<bool, _Allocator>::at(size_type __n) const {
+ if (__n >= size())
+ this->__throw_out_of_range();
+ return (*this)[__n];
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::push_back(const value_type& __x) {
+ if (this->__size_ == this->capacity())
+ reserve(__recommend(this->__size_ + 1));
+ ++this->__size_;
+ back() = __x;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::iterator
+vector<bool, _Allocator>::insert(const_iterator __position, const value_type& __x) {
+ iterator __r;
+ if (size() < capacity()) {
+ const_iterator __old_end = end();
+ ++__size_;
+ std::copy_backward(__position, __old_end, end());
+ __r = __const_iterator_cast(__position);
+ } else {
+ vector __v(get_allocator());
+ __v.reserve(__recommend(__size_ + 1));
+ __v.__size_ = __size_ + 1;
+ __r = std::copy(cbegin(), __position, __v.begin());
+ std::copy_backward(__position, cend(), __v.end());
+ swap(__v);
+ }
+ *__r = __x;
+ return __r;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::iterator
+vector<bool, _Allocator>::insert(const_iterator __position, size_type __n, const value_type& __x) {
+ iterator __r;
+ size_type __c = capacity();
+ if (__n <= __c && size() <= __c - __n) {
+ const_iterator __old_end = end();
+ __size_ += __n;
+ std::copy_backward(__position, __old_end, end());
+ __r = __const_iterator_cast(__position);
+ } else {
+ vector __v(get_allocator());
+ __v.reserve(__recommend(__size_ + __n));
+ __v.__size_ = __size_ + __n;
+ __r = std::copy(cbegin(), __position, __v.begin());
+ std::copy_backward(__position, cend(), __v.end());
+ swap(__v);
+ }
+ std::fill_n(__r, __n, __x);
+ return __r;
+}
+
+template <class _Allocator>
+template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::iterator
+vector<bool, _Allocator>::insert(const_iterator __position, _InputIterator __first, _InputIterator __last) {
+ return __insert_with_sentinel(__position, __first, __last);
+}
+
+template <class _Allocator>
+template <class _InputIterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI typename vector<bool, _Allocator>::iterator
+vector<bool, _Allocator>::__insert_with_sentinel(const_iterator __position, _InputIterator __first, _Sentinel __last) {
+ difference_type __off = __position - begin();
+ iterator __p = __const_iterator_cast(__position);
+ iterator __old_end = end();
+ for (; size() != capacity() && __first != __last; ++__first) {
+ ++this->__size_;
+ back() = *__first;
+ }
+ vector __v(get_allocator());
+ if (__first != __last) {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ try {
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ __v.__assign_with_sentinel(std::move(__first), std::move(__last));
+ difference_type __old_size = static_cast<difference_type>(__old_end - begin());
+ difference_type __old_p = __p - begin();
+ reserve(__recommend(size() + __v.size()));
+ __p = begin() + __old_p;
+ __old_end = begin() + __old_size;
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+ } catch (...) {
+ erase(__old_end, end());
+ throw;
+ }
+#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+ }
+ __p = std::rotate(__p, __old_end, end());
+ insert(__p, __v.begin(), __v.end());
+ return begin() + __off;
+}
+
+template <class _Allocator>
+template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::iterator
+vector<bool, _Allocator>::insert(const_iterator __position, _ForwardIterator __first, _ForwardIterator __last) {
+ return __insert_with_size(__position, __first, __last, std::distance(__first, __last));
+}
+
+template <class _Allocator>
+template <class _ForwardIterator, class _Sentinel>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI typename vector<bool, _Allocator>::iterator
+vector<bool, _Allocator>::__insert_with_size(
+ const_iterator __position, _ForwardIterator __first, _Sentinel __last, difference_type __n_signed) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__n_signed >= 0, "invalid range specified");
+ const size_type __n = static_cast<size_type>(__n_signed);
+ iterator __r;
+ size_type __c = capacity();
+ if (__n <= __c && size() <= __c - __n) {
+ const_iterator __old_end = end();
+ __size_ += __n;
+ std::copy_backward(__position, __old_end, end());
+ __r = __const_iterator_cast(__position);
+ } else {
+ vector __v(get_allocator());
+ __v.reserve(__recommend(__size_ + __n));
+ __v.__size_ = __size_ + __n;
+ __r = std::copy(cbegin(), __position, __v.begin());
+ std::copy_backward(__position, cend(), __v.end());
+ swap(__v);
+ }
+ std::__copy<_ClassicAlgPolicy>(__first, __last, __r);
+ return __r;
+}
+
+template <class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::iterator
+vector<bool, _Allocator>::erase(const_iterator __position) {
+ iterator __r = __const_iterator_cast(__position);
+ std::copy(__position + 1, this->cend(), __r);
+ --__size_;
+ return __r;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::iterator
+vector<bool, _Allocator>::erase(const_iterator __first, const_iterator __last) {
+ iterator __r = __const_iterator_cast(__first);
+ difference_type __d = __last - __first;
+ std::copy(__last, this->cend(), __r);
+ __size_ -= __d;
+ return __r;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::swap(vector& __x)
+#if _LIBCPP_STD_VER >= 14
+ _NOEXCEPT
+#else
+ _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>)
+#endif
+{
+ std::swap(this->__begin_, __x.__begin_);
+ std::swap(this->__size_, __x.__size_);
+ std::swap(this->__cap(), __x.__cap());
+ std::__swap_allocator(
+ this->__alloc(), __x.__alloc(), integral_constant<bool, __alloc_traits::propagate_on_container_swap::value>());
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::resize(size_type __sz, value_type __x) {
+ size_type __cs = size();
+ if (__cs < __sz) {
+ iterator __r;
+ size_type __c = capacity();
+ size_type __n = __sz - __cs;
+ if (__n <= __c && __cs <= __c - __n) {
+ __r = end();
+ __size_ += __n;
+ } else {
+ vector __v(get_allocator());
+ __v.reserve(__recommend(__size_ + __n));
+ __v.__size_ = __size_ + __n;
+ __r = std::copy(cbegin(), cend(), __v.begin());
+ swap(__v);
+ }
+ std::fill_n(__r, __n, __x);
+ } else
+ __size_ = __sz;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<bool, _Allocator>::flip() _NOEXCEPT {
+ // do middle whole words
+ size_type __n = __size_;
+ __storage_pointer __p = __begin_;
+ for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
+ *__p = ~*__p;
+ // do last partial word
+ if (__n > 0) {
+ __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __storage_type __b = *__p & __m;
+ *__p &= ~__m;
+ *__p |= ~__b & __m;
+ }
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 bool vector<bool, _Allocator>::__invariants() const {
+ if (this->__begin_ == nullptr) {
+ if (this->__size_ != 0 || this->__cap() != 0)
+ return false;
+ } else {
+ if (this->__cap() == 0)
+ return false;
+ if (this->__size_ > this->capacity())
+ return false;
+ }
+ return true;
+}
+
+template <class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 size_t vector<bool, _Allocator>::__hash_code() const _NOEXCEPT {
+ size_t __h = 0;
+ // do middle whole words
+ size_type __n = __size_;
+ __storage_pointer __p = __begin_;
+ for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
+ __h ^= *__p;
+ // do last partial word
+ if (__n > 0) {
+ const __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+ __h ^= *__p & __m;
+ }
+ return __h;
+}
+
+template <class _Allocator>
+struct _LIBCPP_TEMPLATE_VIS hash<vector<bool, _Allocator> >
+ : public __unary_function<vector<bool, _Allocator>, size_t> {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_t
+ operator()(const vector<bool, _Allocator>& __vec) const _NOEXCEPT {
+ return __vec.__hash_code();
+ }
+};
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI bool
+operator==(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y) {
+ const typename vector<_Tp, _Allocator>::size_type __sz = __x.size();
+ return __sz == __y.size() && std::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+#if _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y) {
+ return !(__x == __y);
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y) {
+ return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y) {
+ return __y < __x;
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y) {
+ return !(__x < __y);
+}
+
+template <class _Tp, class _Allocator>
+inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y) {
+ return !(__y < __x);
+}
+
+#else // _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Allocator>
+_LIBCPP_HIDE_FROM_ABI constexpr __synth_three_way_result<_Tp>
+operator<=>(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y) {
+ return std::lexicographical_compare_three_way(
+ __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+}
+
+#endif // _LIBCPP_STD_VER <= 17
+
+template <class _Tp, class _Allocator>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
+swap(vector<_Tp, _Allocator>& __x, vector<_Tp, _Allocator>& __y) _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
+ __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER >= 20
+template <class _Tp, class _Allocator, class _Up>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::size_type
+erase(vector<_Tp, _Allocator>& __c, const _Up& __v) {
+ auto __old_size = __c.size();
+ __c.erase(std::remove(__c.begin(), __c.end(), __v), __c.end());
+ return __old_size - __c.size();
+}
+
+template <class _Tp, class _Allocator, class _Predicate>
+_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::size_type
+erase_if(vector<_Tp, _Allocator>& __c, _Predicate __pred) {
+ auto __old_size = __c.size();
+ __c.erase(std::remove_if(__c.begin(), __c.end(), __pred), __c.end());
+ return __old_size - __c.size();
+}
+
+template <>
+inline constexpr bool __format::__enable_insertable<vector<char>> = true;
+# ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+template <>
+inline constexpr bool __format::__enable_insertable<vector<wchar_t>> = true;
+# endif
+
+#endif // _LIBCPP_STD_VER >= 20
+
+#if _LIBCPP_STD_VER >= 23
+template <class _Tp, class _CharT>
+// Since is-vector-bool-reference is only used once it's inlined here.
+ requires same_as<typename _Tp::__container, vector<bool, typename _Tp::__container::allocator_type>>
+struct _LIBCPP_TEMPLATE_VIS formatter<_Tp, _CharT> {
+private:
+ formatter<bool, _CharT> __underlying_;
+
+public:
+ template <class _ParseContext>
+ _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
+ return __underlying_.parse(__ctx);
+ }
+
+ template <class _FormatContext>
+ _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(const _Tp& __ref, _FormatContext& __ctx) const {
+ return __underlying_.format(__ref, __ctx);
+ }
+};
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_END_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+namespace pmr {
+template <class _ValueT>
+using vector _LIBCPP_AVAILABILITY_PMR = std::vector<_ValueT, polymorphic_allocator<_ValueT>>;
+} // namespace pmr
+_LIBCPP_END_NAMESPACE_STD
+#endif
+
+_LIBCPP_POP_MACROS
+
+#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
+# include <algorithm>
+# include <atomic>
+# include <concepts>
+# include <cstdlib>
+# include <iosfwd>
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# include <locale>
+# endif
+# include <tuple>
+# include <type_traits>
+# include <typeinfo>
+# include <utility>
+#endif
+
+#endif // _LIBCPP_VECTOR
diff --git a/libcxx/include/__cxx03/version b/libcxx/include/__cxx03/version
new file mode 100644
index 00000000000000..fe64343eafbc9c
--- /dev/null
+++ b/libcxx/include/__cxx03/version
@@ -0,0 +1,566 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_VERSIONH
+#define _LIBCPP_VERSIONH
+
+/*
+ version synopsis
+
+Macro name Value Headers
+__cpp_lib_adaptor_iterator_pair_constructor 202106L <queue> <stack>
+__cpp_lib_addressof_constexpr 201603L <memory>
+__cpp_lib_allocate_at_least 202302L <memory>
+__cpp_lib_allocator_traits_is_always_equal 201411L <deque> <forward_list> <list>
+ <map> <memory> <scoped_allocator>
+ <set> <string> <unordered_map>
+ <unordered_set> <vector>
+__cpp_lib_any 201606L <any>
+__cpp_lib_apply 201603L <tuple>
+__cpp_lib_array_constexpr 201811L <array> <iterator>
+ 201603L // C++17
+__cpp_lib_as_const 201510L <utility>
+__cpp_lib_associative_heterogeneous_erasure 202110L <map> <set> <unordered_map>
+ <unordered_set>
+__cpp_lib_associative_heterogeneous_insertion 202306L <map> <set> <unordered_map>
+ <unordered_set>
+__cpp_lib_assume_aligned 201811L <memory>
+__cpp_lib_atomic_flag_test 201907L <atomic>
+__cpp_lib_atomic_float 201711L <atomic>
+__cpp_lib_atomic_is_always_lock_free 201603L <atomic>
+__cpp_lib_atomic_lock_free_type_aliases 201907L <atomic>
+__cpp_lib_atomic_min_max 202403L <atomic>
+__cpp_lib_atomic_ref 201806L <atomic>
+__cpp_lib_atomic_shared_ptr 201711L <atomic>
+__cpp_lib_atomic_value_initialization 201911L <atomic> <memory>
+__cpp_lib_atomic_wait 201907L <atomic>
+__cpp_lib_barrier 201907L <barrier>
+__cpp_lib_bind_back 202202L <functional>
+__cpp_lib_bind_front 202306L <functional>
+ 201907L // C++20
+__cpp_lib_bit_cast 201806L <bit>
+__cpp_lib_bitops 201907L <bit>
+__cpp_lib_bitset 202306L <bitset>
+__cpp_lib_bool_constant 201505L <type_traits>
+__cpp_lib_bounded_array_traits 201902L <type_traits>
+__cpp_lib_boyer_moore_searcher 201603L <functional>
+__cpp_lib_byte 201603L <cstddef>
+__cpp_lib_byteswap 202110L <bit>
+__cpp_lib_char8_t 201907L <atomic> <filesystem> <istream>
+ <limits> <locale> <ostream>
+ <string> <string_view>
+__cpp_lib_chrono 201611L <chrono>
+__cpp_lib_chrono_udls 201304L <chrono>
+__cpp_lib_clamp 201603L <algorithm>
+__cpp_lib_complex_udls 201309L <complex>
+__cpp_lib_concepts 202002L <concepts>
+__cpp_lib_constexpr_algorithms 201806L <algorithm> <utility>
+__cpp_lib_constexpr_bitset 202207L <bitset>
+__cpp_lib_constexpr_charconv 202207L <charconv>
+__cpp_lib_constexpr_cmath 202202L <cmath> <cstdlib>
+__cpp_lib_constexpr_complex 201711L <complex>
+__cpp_lib_constexpr_dynamic_alloc 201907L <memory>
+__cpp_lib_constexpr_functional 201907L <functional>
+__cpp_lib_constexpr_iterator 201811L <iterator>
+__cpp_lib_constexpr_memory 202202L <memory>
+ 201811L // C++20
+__cpp_lib_constexpr_new 202406L <new>
+__cpp_lib_constexpr_numeric 201911L <numeric>
+__cpp_lib_constexpr_string 201907L <string>
+__cpp_lib_constexpr_string_view 201811L <string_view>
+__cpp_lib_constexpr_tuple 201811L <tuple>
+__cpp_lib_constexpr_typeinfo 202106L <typeinfo>
+__cpp_lib_constexpr_utility 201811L <utility>
+__cpp_lib_constexpr_vector 201907L <vector>
+__cpp_lib_constrained_equality 202403L <optional> <tuple> <utility>
+ <variant>
+__cpp_lib_containers_ranges 202202L <deque> <forward_list> <list>
+ <map> <queue> <set>
+ <stack> <string> <unordered_map>
+ <unordered_set> <vector>
+__cpp_lib_copyable_function 202306L <functional>
+__cpp_lib_coroutine 201902L <coroutine>
+__cpp_lib_debugging 202311L <debugging>
+__cpp_lib_default_template_type_for_algorithm_values 202403L <algorithm> <deque> <forward_list>
+ <list> <ranges> <string>
+ <vector>
+__cpp_lib_destroying_delete 201806L <new>
+__cpp_lib_enable_shared_from_this 201603L <memory>
+__cpp_lib_endian 201907L <bit>
+__cpp_lib_erase_if 202002L <deque> <forward_list> <list>
+ <map> <set> <string>
+ <unordered_map> <unordered_set> <vector>
+__cpp_lib_exchange_function 201304L <utility>
+__cpp_lib_execution 201902L <execution>
+ 201603L // C++17
+__cpp_lib_expected 202211L <expected>
+__cpp_lib_filesystem 201703L <filesystem>
+__cpp_lib_format 202110L <format>
+__cpp_lib_format_path 202403L <filesystem>
+__cpp_lib_format_ranges 202207L <format>
+__cpp_lib_format_uchar 202311L <format>
+__cpp_lib_formatters 202302L <stacktrace> <thread>
+__cpp_lib_forward_like 202207L <utility>
+__cpp_lib_freestanding_algorithm 202311L <algorithm>
+__cpp_lib_freestanding_array 202311L <array>
+__cpp_lib_freestanding_cstring 202306L <cstring>
+__cpp_lib_freestanding_expected 202311L <expected>
+__cpp_lib_freestanding_mdspan 202311L <mdspan>
+__cpp_lib_freestanding_optional 202311L <optional>
+__cpp_lib_freestanding_string_view 202311L <string_view>
+__cpp_lib_freestanding_variant 202311L <variant>
+__cpp_lib_fstream_native_handle 202306L <fstream>
+__cpp_lib_function_ref 202306L <functional>
+__cpp_lib_gcd_lcm 201606L <numeric>
+__cpp_lib_generate_random 202403L <random>
+__cpp_lib_generic_associative_lookup 201304L <map> <set>
+__cpp_lib_generic_unordered_lookup 201811L <unordered_map> <unordered_set>
+__cpp_lib_hardware_interference_size 201703L <new>
+__cpp_lib_has_unique_object_representations 201606L <type_traits>
+__cpp_lib_hazard_pointer 202306L <hazard_pointer>
+__cpp_lib_hypot 201603L <cmath>
+__cpp_lib_incomplete_container_elements 201505L <forward_list> <list> <vector>
+__cpp_lib_inplace_vector 202406L <inplace_vector>
+__cpp_lib_int_pow2 202002L <bit>
+__cpp_lib_integer_comparison_functions 202002L <utility>
+__cpp_lib_integer_sequence 201304L <utility>
+__cpp_lib_integral_constant_callable 201304L <type_traits>
+__cpp_lib_interpolate 201902L <cmath> <numeric>
+__cpp_lib_invoke 201411L <functional>
+__cpp_lib_invoke_r 202106L <functional>
+__cpp_lib_ios_noreplace 202207L <ios>
+__cpp_lib_is_aggregate 201703L <type_traits>
+__cpp_lib_is_constant_evaluated 201811L <type_traits>
+__cpp_lib_is_final 201402L <type_traits>
+__cpp_lib_is_invocable 201703L <type_traits>
+__cpp_lib_is_layout_compatible 201907L <type_traits>
+__cpp_lib_is_nothrow_convertible 201806L <type_traits>
+__cpp_lib_is_null_pointer 201309L <type_traits>
+__cpp_lib_is_pointer_interconvertible 201907L <type_traits>
+__cpp_lib_is_scoped_enum 202011L <type_traits>
+__cpp_lib_is_swappable 201603L <type_traits>
+__cpp_lib_is_virtual_base_of 202406L <type_traits>
+__cpp_lib_is_within_lifetime 202306L <type_traits>
+__cpp_lib_jthread 201911L <stop_token> <thread>
+__cpp_lib_latch 201907L <latch>
+__cpp_lib_launder 201606L <new>
+__cpp_lib_linalg 202311L <linalg>
+__cpp_lib_list_remove_return_type 201806L <forward_list> <list>
+__cpp_lib_logical_traits 201510L <type_traits>
+__cpp_lib_make_from_tuple 201606L <tuple>
+__cpp_lib_make_reverse_iterator 201402L <iterator>
+__cpp_lib_make_unique 201304L <memory>
+__cpp_lib_map_try_emplace 201411L <map>
+__cpp_lib_math_constants 201907L <numbers>
+__cpp_lib_math_special_functions 201603L <cmath>
+__cpp_lib_mdspan 202406L <mdspan>
+ 202207L // C++23
+__cpp_lib_memory_resource 201603L <memory_resource>
+__cpp_lib_move_iterator_concept 202207L <iterator>
+__cpp_lib_move_only_function 202110L <functional>
+__cpp_lib_node_extract 201606L <map> <set> <unordered_map>
+ <unordered_set>
+__cpp_lib_nonmember_container_access 201411L <array> <deque> <forward_list>
+ <iterator> <list> <map>
+ <regex> <set> <string>
+ <unordered_map> <unordered_set> <vector>
+__cpp_lib_not_fn 201603L <functional>
+__cpp_lib_null_iterators 201304L <iterator>
+__cpp_lib_optional 202110L <optional>
+ 201606L // C++17
+__cpp_lib_optional_range_support 202406L <optional>
+__cpp_lib_out_ptr 202311L <memory>
+ 202106L // C++23
+__cpp_lib_parallel_algorithm 201603L <algorithm> <numeric>
+__cpp_lib_philox_engine 202406L <random>
+__cpp_lib_polymorphic_allocator 201902L <memory_resource>
+__cpp_lib_print 202207L <ostream> <print>
+__cpp_lib_quoted_string_io 201304L <iomanip>
+__cpp_lib_ranges 202207L <algorithm> <functional> <iterator>
+ <memory> <ranges>
+__cpp_lib_ranges_as_const 202207L <ranges>
+__cpp_lib_ranges_as_rvalue 202207L <ranges>
+__cpp_lib_ranges_chunk 202202L <ranges>
+__cpp_lib_ranges_chunk_by 202202L <ranges>
+__cpp_lib_ranges_concat 202403L <ranges>
+__cpp_lib_ranges_contains 202207L <algorithm>
+__cpp_lib_ranges_find_last 202207L <algorithm>
+__cpp_lib_ranges_iota 202202L <numeric>
+__cpp_lib_ranges_join_with 202202L <ranges>
+__cpp_lib_ranges_repeat 202207L <ranges>
+__cpp_lib_ranges_slide 202202L <ranges>
+__cpp_lib_ranges_starts_ends_with 202106L <algorithm>
+__cpp_lib_ranges_to_container 202202L <ranges>
+__cpp_lib_ranges_zip 202110L <ranges> <tuple> <utility>
+__cpp_lib_ratio 202306L <ratio>
+__cpp_lib_raw_memory_algorithms 201606L <memory>
+__cpp_lib_rcu 202306L <rcu>
+__cpp_lib_reference_from_temporary 202202L <type_traits>
+__cpp_lib_reference_wrapper 202403L <functional>
+__cpp_lib_remove_cvref 201711L <type_traits>
+__cpp_lib_result_of_sfinae 201210L <functional> <type_traits>
+__cpp_lib_robust_nonmodifying_seq_ops 201304L <algorithm>
+__cpp_lib_sample 201603L <algorithm>
+__cpp_lib_saturation_arithmetic 202311L <numeric>
+__cpp_lib_scoped_lock 201703L <mutex>
+__cpp_lib_semaphore 201907L <semaphore>
+__cpp_lib_senders 202406L <execution>
+__cpp_lib_shared_mutex 201505L <shared_mutex>
+__cpp_lib_shared_ptr_arrays 201707L <memory>
+ 201611L // C++17
+__cpp_lib_shared_ptr_weak_type 201606L <memory>
+__cpp_lib_shared_timed_mutex 201402L <shared_mutex>
+__cpp_lib_shift 201806L <algorithm>
+__cpp_lib_smart_ptr_for_overwrite 202002L <memory>
+__cpp_lib_smart_ptr_owner_equality 202306L <memory>
+__cpp_lib_source_location 201907L <source_location>
+__cpp_lib_span 202002L <span>
+__cpp_lib_span_at 202311L <span>
+__cpp_lib_span_initializer_list 202311L <span>
+__cpp_lib_spanstream 202106L <spanstream>
+__cpp_lib_ssize 201902L <iterator>
+__cpp_lib_sstream_from_string_view 202306L <sstream>
+__cpp_lib_stacktrace 202011L <stacktrace>
+__cpp_lib_starts_ends_with 201711L <string> <string_view>
+__cpp_lib_stdatomic_h 202011L <stdatomic.h>
+__cpp_lib_string_contains 202011L <string> <string_view>
+__cpp_lib_string_resize_and_overwrite 202110L <string>
+__cpp_lib_string_udls 201304L <string>
+__cpp_lib_string_view 202403L <string> <string_view>
+ 201803L // C++20
+ 201606L // C++17
+__cpp_lib_submdspan 202306L <mdspan>
+__cpp_lib_syncbuf 201803L <syncstream>
+__cpp_lib_text_encoding 202306L <text_encoding>
+__cpp_lib_three_way_comparison 201907L <compare>
+__cpp_lib_to_address 201711L <memory>
+__cpp_lib_to_array 201907L <array>
+__cpp_lib_to_chars 202306L <charconv>
+ 201611L // C++17
+__cpp_lib_to_string 202306L <string>
+__cpp_lib_to_underlying 202102L <utility>
+__cpp_lib_transformation_trait_aliases 201304L <type_traits>
+__cpp_lib_transparent_operators 201510L <functional> <memory>
+ 201210L // C++14
+__cpp_lib_tuple_element_t 201402L <tuple>
+__cpp_lib_tuple_like 202311L <map> <tuple> <unordered_map>
+ <utility>
+ 202207L // C++23
+__cpp_lib_tuples_by_type 201304L <tuple> <utility>
+__cpp_lib_type_identity 201806L <type_traits>
+__cpp_lib_type_trait_variable_templates 201510L <type_traits>
+__cpp_lib_uncaught_exceptions 201411L <exception>
+__cpp_lib_unordered_map_try_emplace 201411L <unordered_map>
+__cpp_lib_unreachable 202202L <utility>
+__cpp_lib_unwrap_ref 201811L <functional>
+__cpp_lib_variant 202102L <variant>
+__cpp_lib_void_t 201411L <type_traits>
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// clang-format off
+
+#if _LIBCPP_STD_VER >= 14
+# define __cpp_lib_chrono_udls 201304L
+# define __cpp_lib_complex_udls 201309L
+# define __cpp_lib_exchange_function 201304L
+# define __cpp_lib_generic_associative_lookup 201304L
+# define __cpp_lib_integer_sequence 201304L
+# define __cpp_lib_integral_constant_callable 201304L
+# define __cpp_lib_is_final 201402L
+# define __cpp_lib_is_null_pointer 201309L
+# define __cpp_lib_make_reverse_iterator 201402L
+# define __cpp_lib_make_unique 201304L
+# define __cpp_lib_null_iterators 201304L
+# if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# define __cpp_lib_quoted_string_io 201304L
+# endif
+# define __cpp_lib_result_of_sfinae 201210L
+# define __cpp_lib_robust_nonmodifying_seq_ops 201304L
+# if !defined(_LIBCPP_HAS_NO_THREADS)
+# define __cpp_lib_shared_timed_mutex 201402L
+# endif
+# define __cpp_lib_string_udls 201304L
+# define __cpp_lib_transformation_trait_aliases 201304L
+# define __cpp_lib_transparent_operators 201210L
+# define __cpp_lib_tuple_element_t 201402L
+# define __cpp_lib_tuples_by_type 201304L
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+# define __cpp_lib_addressof_constexpr 201603L
+# define __cpp_lib_allocator_traits_is_always_equal 201411L
+# define __cpp_lib_any 201606L
+# define __cpp_lib_apply 201603L
+# define __cpp_lib_array_constexpr 201603L
+# define __cpp_lib_as_const 201510L
+# define __cpp_lib_atomic_is_always_lock_free 201603L
+# define __cpp_lib_bool_constant 201505L
+# define __cpp_lib_boyer_moore_searcher 201603L
+# define __cpp_lib_byte 201603L
+# define __cpp_lib_chrono 201611L
+# define __cpp_lib_clamp 201603L
+# define __cpp_lib_enable_shared_from_this 201603L
+// # define __cpp_lib_execution 201603L
+# if !defined(_LIBCPP_HAS_NO_FILESYSTEM) && _LIBCPP_AVAILABILITY_HAS_FILESYSTEM_LIBRARY
+# define __cpp_lib_filesystem 201703L
+# endif
+# define __cpp_lib_gcd_lcm 201606L
+# if defined(__GCC_DESTRUCTIVE_SIZE) && defined(__GCC_CONSTRUCTIVE_SIZE)
+# define __cpp_lib_hardware_interference_size 201703L
+# endif
+# define __cpp_lib_has_unique_object_representations 201606L
+# define __cpp_lib_hypot 201603L
+# define __cpp_lib_incomplete_container_elements 201505L
+# define __cpp_lib_invoke 201411L
+# define __cpp_lib_is_aggregate 201703L
+# define __cpp_lib_is_invocable 201703L
+# define __cpp_lib_is_swappable 201603L
+# define __cpp_lib_launder 201606L
+# define __cpp_lib_logical_traits 201510L
+# define __cpp_lib_make_from_tuple 201606L
+# define __cpp_lib_map_try_emplace 201411L
+// # define __cpp_lib_math_special_functions 201603L
+# if _LIBCPP_AVAILABILITY_HAS_PMR
+# define __cpp_lib_memory_resource 201603L
+# endif
+# define __cpp_lib_node_extract 201606L
+# define __cpp_lib_nonmember_container_access 201411L
+# define __cpp_lib_not_fn 201603L
+# define __cpp_lib_optional 201606L
+// # define __cpp_lib_parallel_algorithm 201603L
+# define __cpp_lib_raw_memory_algorithms 201606L
+# define __cpp_lib_sample 201603L
+# if !defined(_LIBCPP_HAS_NO_THREADS)
+# define __cpp_lib_scoped_lock 201703L
+# endif
+# if !defined(_LIBCPP_HAS_NO_THREADS)
+# define __cpp_lib_shared_mutex 201505L
+# endif
+# define __cpp_lib_shared_ptr_arrays 201611L
+# define __cpp_lib_shared_ptr_weak_type 201606L
+# define __cpp_lib_string_view 201606L
+// # define __cpp_lib_to_chars 201611L
+# undef __cpp_lib_transparent_operators
+# define __cpp_lib_transparent_operators 201510L
+# define __cpp_lib_type_trait_variable_templates 201510L
+# define __cpp_lib_uncaught_exceptions 201411L
+# define __cpp_lib_unordered_map_try_emplace 201411L
+# define __cpp_lib_variant 202102L
+# define __cpp_lib_void_t 201411L
+#endif
+
+#if _LIBCPP_STD_VER >= 20
+# undef __cpp_lib_array_constexpr
+# define __cpp_lib_array_constexpr 201811L
+# define __cpp_lib_assume_aligned 201811L
+# define __cpp_lib_atomic_flag_test 201907L
+// # define __cpp_lib_atomic_float 201711L
+# define __cpp_lib_atomic_lock_free_type_aliases 201907L
+# define __cpp_lib_atomic_ref 201806L
+// # define __cpp_lib_atomic_shared_ptr 201711L
+# define __cpp_lib_atomic_value_initialization 201911L
+# if _LIBCPP_AVAILABILITY_HAS_SYNC
+# define __cpp_lib_atomic_wait 201907L
+# endif
+# if !defined(_LIBCPP_HAS_NO_THREADS) && _LIBCPP_AVAILABILITY_HAS_SYNC
+# define __cpp_lib_barrier 201907L
+# endif
+# define __cpp_lib_bind_front 201907L
+# define __cpp_lib_bit_cast 201806L
+# define __cpp_lib_bitops 201907L
+# define __cpp_lib_bounded_array_traits 201902L
+# if !defined(_LIBCPP_HAS_NO_CHAR8_T)
+# define __cpp_lib_char8_t 201907L
+# endif
+# define __cpp_lib_concepts 202002L
+# define __cpp_lib_constexpr_algorithms 201806L
+# define __cpp_lib_constexpr_complex 201711L
+# define __cpp_lib_constexpr_dynamic_alloc 201907L
+# define __cpp_lib_constexpr_functional 201907L
+# define __cpp_lib_constexpr_iterator 201811L
+# define __cpp_lib_constexpr_memory 201811L
+# define __cpp_lib_constexpr_numeric 201911L
+# define __cpp_lib_constexpr_string 201907L
+# define __cpp_lib_constexpr_string_view 201811L
+# define __cpp_lib_constexpr_tuple 201811L
+# define __cpp_lib_constexpr_utility 201811L
+# define __cpp_lib_constexpr_vector 201907L
+# define __cpp_lib_coroutine 201902L
+# if _LIBCPP_STD_VER >= 20 && defined(__cpp_impl_destroying_delete) && __cpp_impl_destroying_delete >= 201806L
+# define __cpp_lib_destroying_delete 201806L
+# endif
+# define __cpp_lib_endian 201907L
+# define __cpp_lib_erase_if 202002L
+# undef __cpp_lib_execution
+// # define __cpp_lib_execution 201902L
+# define __cpp_lib_format 202110L
+# define __cpp_lib_format_uchar 202311L
+# define __cpp_lib_generic_unordered_lookup 201811L
+# define __cpp_lib_int_pow2 202002L
+# define __cpp_lib_integer_comparison_functions 202002L
+# define __cpp_lib_interpolate 201902L
+# define __cpp_lib_is_constant_evaluated 201811L
+// # define __cpp_lib_is_layout_compatible 201907L
+# define __cpp_lib_is_nothrow_convertible 201806L
+// # define __cpp_lib_is_pointer_interconvertible 201907L
+# if !defined(_LIBCPP_HAS_NO_THREADS) && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && _LIBCPP_AVAILABILITY_HAS_SYNC
+# define __cpp_lib_jthread 201911L
+# endif
+# if !defined(_LIBCPP_HAS_NO_THREADS) && _LIBCPP_AVAILABILITY_HAS_SYNC
+# define __cpp_lib_latch 201907L
+# endif
+# define __cpp_lib_list_remove_return_type 201806L
+# define __cpp_lib_math_constants 201907L
+# define __cpp_lib_move_iterator_concept 202207L
+# if _LIBCPP_AVAILABILITY_HAS_PMR
+# define __cpp_lib_polymorphic_allocator 201902L
+# endif
+# define __cpp_lib_ranges 202207L
+# define __cpp_lib_remove_cvref 201711L
+# if !defined(_LIBCPP_HAS_NO_THREADS) && _LIBCPP_AVAILABILITY_HAS_SYNC
+# define __cpp_lib_semaphore 201907L
+# endif
+# undef __cpp_lib_shared_ptr_arrays
+# define __cpp_lib_shared_ptr_arrays 201707L
+# define __cpp_lib_shift 201806L
+// # define __cpp_lib_smart_ptr_for_overwrite 202002L
+# define __cpp_lib_source_location 201907L
+# define __cpp_lib_span 202002L
+# define __cpp_lib_ssize 201902L
+# define __cpp_lib_starts_ends_with 201711L
+# undef __cpp_lib_string_view
+# define __cpp_lib_string_view 201803L
+# if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_SYNCSTREAM)
+# define __cpp_lib_syncbuf 201803L
+# endif
+# define __cpp_lib_three_way_comparison 201907L
+# define __cpp_lib_to_address 201711L
+# define __cpp_lib_to_array 201907L
+# define __cpp_lib_type_identity 201806L
+# define __cpp_lib_unwrap_ref 201811L
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+# define __cpp_lib_adaptor_iterator_pair_constructor 202106L
+# define __cpp_lib_allocate_at_least 202302L
+// # define __cpp_lib_associative_heterogeneous_erasure 202110L
+# define __cpp_lib_bind_back 202202L
+# define __cpp_lib_byteswap 202110L
+# define __cpp_lib_constexpr_bitset 202207L
+# define __cpp_lib_constexpr_charconv 202207L
+// # define __cpp_lib_constexpr_cmath 202202L
+# undef __cpp_lib_constexpr_memory
+# define __cpp_lib_constexpr_memory 202202L
+# define __cpp_lib_constexpr_typeinfo 202106L
+# define __cpp_lib_containers_ranges 202202L
+# define __cpp_lib_expected 202211L
+# define __cpp_lib_format_ranges 202207L
+// # define __cpp_lib_formatters 202302L
+# define __cpp_lib_forward_like 202207L
+# define __cpp_lib_invoke_r 202106L
+# define __cpp_lib_ios_noreplace 202207L
+# define __cpp_lib_is_scoped_enum 202011L
+# define __cpp_lib_mdspan 202207L
+# define __cpp_lib_modules 202207L
+// # define __cpp_lib_move_only_function 202110L
+# undef __cpp_lib_optional
+# define __cpp_lib_optional 202110L
+# define __cpp_lib_out_ptr 202106L
+# define __cpp_lib_print 202207L
+// # define __cpp_lib_ranges_as_const 202207L
+# define __cpp_lib_ranges_as_rvalue 202207L
+// # define __cpp_lib_ranges_chunk 202202L
+# define __cpp_lib_ranges_chunk_by 202202L
+# define __cpp_lib_ranges_contains 202207L
+# define __cpp_lib_ranges_find_last 202207L
+// # define __cpp_lib_ranges_iota 202202L
+// # define __cpp_lib_ranges_join_with 202202L
+# define __cpp_lib_ranges_repeat 202207L
+// # define __cpp_lib_ranges_slide 202202L
+# define __cpp_lib_ranges_starts_ends_with 202106L
+# define __cpp_lib_ranges_to_container 202202L
+// # define __cpp_lib_ranges_zip 202110L
+// # define __cpp_lib_reference_from_temporary 202202L
+// # define __cpp_lib_spanstream 202106L
+// # define __cpp_lib_stacktrace 202011L
+# define __cpp_lib_stdatomic_h 202011L
+# define __cpp_lib_string_contains 202011L
+# define __cpp_lib_string_resize_and_overwrite 202110L
+# define __cpp_lib_to_underlying 202102L
+// # define __cpp_lib_tuple_like 202207L
+# define __cpp_lib_unreachable 202202L
+#endif
+
+#if _LIBCPP_STD_VER >= 26
+// # define __cpp_lib_associative_heterogeneous_insertion 202306L
+// # define __cpp_lib_atomic_min_max 202403L
+# undef __cpp_lib_bind_front
+# define __cpp_lib_bind_front 202306L
+# define __cpp_lib_bitset 202306L
+// # define __cpp_lib_constexpr_new 202406L
+// # define __cpp_lib_constrained_equality 202403L
+// # define __cpp_lib_copyable_function 202306L
+// # define __cpp_lib_debugging 202311L
+// # define __cpp_lib_default_template_type_for_algorithm_values 202403L
+// # define __cpp_lib_format_path 202403L
+// # define __cpp_lib_freestanding_algorithm 202311L
+// # define __cpp_lib_freestanding_array 202311L
+// # define __cpp_lib_freestanding_cstring 202306L
+// # define __cpp_lib_freestanding_expected 202311L
+// # define __cpp_lib_freestanding_mdspan 202311L
+// # define __cpp_lib_freestanding_optional 202311L
+// # define __cpp_lib_freestanding_string_view 202311L
+// # define __cpp_lib_freestanding_variant 202311L
+# if !defined(_LIBCPP_HAS_NO_FILESYSTEM) && !defined(_LIBCPP_HAS_NO_LOCALIZATION)
+# define __cpp_lib_fstream_native_handle 202306L
+# endif
+// # define __cpp_lib_function_ref 202306L
+// # define __cpp_lib_generate_random 202403L
+// # define __cpp_lib_hazard_pointer 202306L
+// # define __cpp_lib_inplace_vector 202406L
+// # define __cpp_lib_is_virtual_base_of 202406L
+// # define __cpp_lib_is_within_lifetime 202306L
+// # define __cpp_lib_linalg 202311L
+# undef __cpp_lib_mdspan
+# define __cpp_lib_mdspan 202406L
+// # define __cpp_lib_optional_range_support 202406L
+# undef __cpp_lib_out_ptr
+# define __cpp_lib_out_ptr 202311L
+// # define __cpp_lib_philox_engine 202406L
+// # define __cpp_lib_ranges_concat 202403L
+# define __cpp_lib_ratio 202306L
+// # define __cpp_lib_rcu 202306L
+# define __cpp_lib_reference_wrapper 202403L
+# define __cpp_lib_saturation_arithmetic 202311L
+// # define __cpp_lib_senders 202406L
+// # define __cpp_lib_smart_ptr_owner_equality 202306L
+# define __cpp_lib_span_at 202311L
+# define __cpp_lib_span_initializer_list 202311L
+# define __cpp_lib_sstream_from_string_view 202306L
+# undef __cpp_lib_string_view
+# define __cpp_lib_string_view 202403L
+// # define __cpp_lib_submdspan 202306L
+// # define __cpp_lib_text_encoding 202306L
+# undef __cpp_lib_to_chars
+// # define __cpp_lib_to_chars 202306L
+// # define __cpp_lib_to_string 202306L
+# undef __cpp_lib_tuple_like
+// # define __cpp_lib_tuple_like 202311L
+#endif
+
+// clang-format on
+
+#endif // _LIBCPP_VERSIONH
diff --git a/libcxx/include/__cxx03/wchar.h b/libcxx/include/__cxx03/wchar.h
new file mode 100644
index 00000000000000..d4268c6d2c2442
--- /dev/null
+++ b/libcxx/include/__cxx03/wchar.h
@@ -0,0 +1,211 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#if defined(__need_wint_t) || defined(__need_mbstate_t)
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+# include_next <wchar.h>
+
+#elif !defined(_LIBCPP_WCHAR_H)
+# define _LIBCPP_WCHAR_H
+
+/*
+ wchar.h synopsis
+
+Macros:
+
+ NULL
+ WCHAR_MAX
+ WCHAR_MIN
+ WEOF
+
+Types:
+
+ mbstate_t
+ size_t
+ tm
+ wint_t
+
+int fwprintf(FILE* restrict stream, const wchar_t* restrict format, ...);
+int fwscanf(FILE* restrict stream, const wchar_t* restrict format, ...);
+int swprintf(wchar_t* restrict s, size_t n, const wchar_t* restrict format, ...);
+int swscanf(const wchar_t* restrict s, const wchar_t* restrict format, ...);
+int vfwprintf(FILE* restrict stream, const wchar_t* restrict format, va_list arg);
+int vfwscanf(FILE* restrict stream, const wchar_t* restrict format, va_list arg); // C99
+int vswprintf(wchar_t* restrict s, size_t n, const wchar_t* restrict format, va_list arg);
+int vswscanf(const wchar_t* restrict s, const wchar_t* restrict format, va_list arg); // C99
+int vwprintf(const wchar_t* restrict format, va_list arg);
+int vwscanf(const wchar_t* restrict format, va_list arg); // C99
+int wprintf(const wchar_t* restrict format, ...);
+int wscanf(const wchar_t* restrict format, ...);
+wint_t fgetwc(FILE* stream);
+wchar_t* fgetws(wchar_t* restrict s, int n, FILE* restrict stream);
+wint_t fputwc(wchar_t c, FILE* stream);
+int fputws(const wchar_t* restrict s, FILE* restrict stream);
+int fwide(FILE* stream, int mode);
+wint_t getwc(FILE* stream);
+wint_t getwchar();
+wint_t putwc(wchar_t c, FILE* stream);
+wint_t putwchar(wchar_t c);
+wint_t ungetwc(wint_t c, FILE* stream);
+double wcstod(const wchar_t* restrict nptr, wchar_t** restrict endptr);
+float wcstof(const wchar_t* restrict nptr, wchar_t** restrict endptr); // C99
+long double wcstold(const wchar_t* restrict nptr, wchar_t** restrict endptr); // C99
+long wcstol(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base);
+long long wcstoll(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base); // C99
+unsigned long wcstoul(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base);
+unsigned long long wcstoull(const wchar_t* restrict nptr, wchar_t** restrict endptr, int base); // C99
+wchar_t* wcscpy(wchar_t* restrict s1, const wchar_t* restrict s2);
+wchar_t* wcsncpy(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+wchar_t* wcscat(wchar_t* restrict s1, const wchar_t* restrict s2);
+wchar_t* wcsncat(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+int wcscmp(const wchar_t* s1, const wchar_t* s2);
+int wcscoll(const wchar_t* s1, const wchar_t* s2);
+int wcsncmp(const wchar_t* s1, const wchar_t* s2, size_t n);
+size_t wcsxfrm(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+const wchar_t* wcschr(const wchar_t* s, wchar_t c);
+ wchar_t* wcschr( wchar_t* s, wchar_t c);
+size_t wcscspn(const wchar_t* s1, const wchar_t* s2);
+size_t wcslen(const wchar_t* s);
+const wchar_t* wcspbrk(const wchar_t* s1, const wchar_t* s2);
+ wchar_t* wcspbrk( wchar_t* s1, const wchar_t* s2);
+const wchar_t* wcsrchr(const wchar_t* s, wchar_t c);
+ wchar_t* wcsrchr( wchar_t* s, wchar_t c);
+size_t wcsspn(const wchar_t* s1, const wchar_t* s2);
+const wchar_t* wcsstr(const wchar_t* s1, const wchar_t* s2);
+ wchar_t* wcsstr( wchar_t* s1, const wchar_t* s2);
+wchar_t* wcstok(wchar_t* restrict s1, const wchar_t* restrict s2, wchar_t** restrict ptr);
+const wchar_t* wmemchr(const wchar_t* s, wchar_t c, size_t n);
+ wchar_t* wmemchr( wchar_t* s, wchar_t c, size_t n);
+int wmemcmp(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+wchar_t* wmemcpy(wchar_t* restrict s1, const wchar_t* restrict s2, size_t n);
+wchar_t* wmemmove(wchar_t* s1, const wchar_t* s2, size_t n);
+wchar_t* wmemset(wchar_t* s, wchar_t c, size_t n);
+size_t wcsftime(wchar_t* restrict s, size_t maxsize, const wchar_t* restrict format,
+ const tm* restrict timeptr);
+wint_t btowc(int c);
+int wctob(wint_t c);
+int mbsinit(const mbstate_t* ps);
+size_t mbrlen(const char* restrict s, size_t n, mbstate_t* restrict ps);
+size_t mbrtowc(wchar_t* restrict pwc, const char* restrict s, size_t n, mbstate_t* restrict ps);
+size_t wcrtomb(char* restrict s, wchar_t wc, mbstate_t* restrict ps);
+size_t mbsrtowcs(wchar_t* restrict dst, const char** restrict src, size_t len,
+ mbstate_t* restrict ps);
+size_t wcsrtombs(char* restrict dst, const wchar_t** restrict src, size_t len,
+ mbstate_t* restrict ps);
+
+*/
+
+# include <__config>
+# include <stddef.h>
+
+# if defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+# error \
+ "The <wchar.h> header is not supported since libc++ has been configured with LIBCXX_ENABLE_WIDE_CHARACTERS disabled"
+# endif
+
+# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+# endif
+
+// We define this here to support older versions of glibc <wchar.h> that do
+// not define this for clang.
+# ifdef __cplusplus
+# define __CORRECT_ISO_CPP_WCHAR_H_PROTO
+# endif
+
+# if __has_include_next(<wchar.h>)
+# include_next <wchar.h>
+# else
+# include <__mbstate_t.h> // make sure we have mbstate_t regardless of the existence of <wchar.h>
+# endif
+
+// Determine whether we have const-correct overloads for wcschr and friends.
+# if defined(_WCHAR_H_CPLUSPLUS_98_CONFORMANCE_)
+# define _LIBCPP_WCHAR_H_HAS_CONST_OVERLOADS 1
+# elif defined(__GLIBC_PREREQ)
+# if __GLIBC_PREREQ(2, 10)
+# define _LIBCPP_WCHAR_H_HAS_CONST_OVERLOADS 1
+# endif
+# elif defined(_LIBCPP_MSVCRT)
+# if defined(_CRT_CONST_CORRECT_OVERLOADS)
+# define _LIBCPP_WCHAR_H_HAS_CONST_OVERLOADS 1
+# endif
+# endif
+
+# if defined(__cplusplus) && !defined(_LIBCPP_WCHAR_H_HAS_CONST_OVERLOADS) && defined(_LIBCPP_PREFERRED_OVERLOAD)
+extern "C++" {
+inline _LIBCPP_HIDE_FROM_ABI wchar_t* __libcpp_wcschr(const wchar_t* __s, wchar_t __c) {
+ return (wchar_t*)wcschr(__s, __c);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const wchar_t* wcschr(const wchar_t* __s, wchar_t __c) {
+ return __libcpp_wcschr(__s, __c);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD wchar_t* wcschr(wchar_t* __s, wchar_t __c) {
+ return __libcpp_wcschr(__s, __c);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI wchar_t* __libcpp_wcspbrk(const wchar_t* __s1, const wchar_t* __s2) {
+ return (wchar_t*)wcspbrk(__s1, __s2);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const wchar_t*
+wcspbrk(const wchar_t* __s1, const wchar_t* __s2) {
+ return __libcpp_wcspbrk(__s1, __s2);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD wchar_t* wcspbrk(wchar_t* __s1, const wchar_t* __s2) {
+ return __libcpp_wcspbrk(__s1, __s2);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI wchar_t* __libcpp_wcsrchr(const wchar_t* __s, wchar_t __c) {
+ return (wchar_t*)wcsrchr(__s, __c);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const wchar_t* wcsrchr(const wchar_t* __s, wchar_t __c) {
+ return __libcpp_wcsrchr(__s, __c);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD wchar_t* wcsrchr(wchar_t* __s, wchar_t __c) {
+ return __libcpp_wcsrchr(__s, __c);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI wchar_t* __libcpp_wcsstr(const wchar_t* __s1, const wchar_t* __s2) {
+ return (wchar_t*)wcsstr(__s1, __s2);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const wchar_t*
+wcsstr(const wchar_t* __s1, const wchar_t* __s2) {
+ return __libcpp_wcsstr(__s1, __s2);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD wchar_t* wcsstr(wchar_t* __s1, const wchar_t* __s2) {
+ return __libcpp_wcsstr(__s1, __s2);
+}
+
+inline _LIBCPP_HIDE_FROM_ABI wchar_t* __libcpp_wmemchr(const wchar_t* __s, wchar_t __c, size_t __n) {
+ return (wchar_t*)wmemchr(__s, __c, __n);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD const wchar_t*
+wmemchr(const wchar_t* __s, wchar_t __c, size_t __n) {
+ return __libcpp_wmemchr(__s, __c, __n);
+}
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD wchar_t* wmemchr(wchar_t* __s, wchar_t __c, size_t __n) {
+ return __libcpp_wmemchr(__s, __c, __n);
+}
+}
+# endif
+
+# if defined(__cplusplus) && (defined(_LIBCPP_MSVCRT_LIKE) || defined(__MVS__))
+extern "C" {
+size_t mbsnrtowcs(
+ wchar_t* __restrict __dst, const char** __restrict __src, size_t __nmc, size_t __len, mbstate_t* __restrict __ps);
+size_t wcsnrtombs(
+ char* __restrict __dst, const wchar_t** __restrict __src, size_t __nwc, size_t __len, mbstate_t* __restrict __ps);
+} // extern "C"
+# endif // __cplusplus && (_LIBCPP_MSVCRT || __MVS__)
+
+#endif // _LIBCPP_WCHAR_H
diff --git a/libcxx/include/__cxx03/wctype.h b/libcxx/include/__cxx03/wctype.h
new file mode 100644
index 00000000000000..c76ec5a3f06085
--- /dev/null
+++ b/libcxx/include/__cxx03/wctype.h
@@ -0,0 +1,95 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_WCTYPE_H
+#define _LIBCPP_WCTYPE_H
+
+/*
+ wctype.h synopsis
+
+Macros:
+
+ WEOF
+
+Types:
+
+ wint_t
+ wctrans_t
+ wctype_t
+
+int iswalnum(wint_t wc);
+int iswalpha(wint_t wc);
+int iswblank(wint_t wc); // C99
+int iswcntrl(wint_t wc);
+int iswdigit(wint_t wc);
+int iswgraph(wint_t wc);
+int iswlower(wint_t wc);
+int iswprint(wint_t wc);
+int iswpunct(wint_t wc);
+int iswspace(wint_t wc);
+int iswupper(wint_t wc);
+int iswxdigit(wint_t wc);
+int iswctype(wint_t wc, wctype_t desc);
+wctype_t wctype(const char* property);
+wint_t towlower(wint_t wc);
+wint_t towupper(wint_t wc);
+wint_t towctrans(wint_t wc, wctrans_t desc);
+wctrans_t wctrans(const char* property);
+
+*/
+
+#include <__config>
+
+#if defined(_LIBCPP_HAS_NO_WIDE_CHARACTERS)
+# error \
+ "The <wctype.h> header is not supported since libc++ has been configured with LIBCXX_ENABLE_WIDE_CHARACTERS disabled"
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+// TODO:
+// In the future, we should unconditionally include_next <wctype.h> here and instead
+// have a mode under which the library does not need libc++'s <wctype.h> or <cwctype>
+// at all (i.e. a mode without wchar_t). As it stands, we need to do that to completely
+// bypass the using declarations in <cwctype> when we did not include <wctype.h>.
+// Otherwise, a using declaration like `using ::wint_t` in <cwctype> will refer to
+// nothing (with using_if_exists), and if we include another header that defines one
+// of these declarations (e.g. <wchar.h>), the second `using ::wint_t` with using_if_exists
+// will fail because it does not refer to the same declaration.
+#if __has_include_next(<wctype.h>)
+# include_next <wctype.h>
+# define _LIBCPP_INCLUDED_C_LIBRARY_WCTYPE_H
+#endif
+
+#ifdef __cplusplus
+
+# undef iswalnum
+# undef iswalpha
+# undef iswblank
+# undef iswcntrl
+# undef iswdigit
+# undef iswgraph
+# undef iswlower
+# undef iswprint
+# undef iswpunct
+# undef iswspace
+# undef iswupper
+# undef iswxdigit
+# undef iswctype
+# undef wctype
+# undef towlower
+# undef towupper
+# undef towctrans
+# undef wctrans
+
+#endif // __cplusplus
+
+#endif // _LIBCPP_WCTYPE_H
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