[libcxx-commits] [libcxx] 06673a9 - [libc++] Uglify non-standard member typedef const_reference in bitset (#121620)
via libcxx-commits
libcxx-commits at lists.llvm.org
Thu Jan 9 01:42:44 PST 2025
Author: Peng Liu
Date: 2025-01-09T17:42:40+08:00
New Revision: 06673a9e9b186a65f5eb60a59a4ee9afba6637d4
URL: https://github.com/llvm/llvm-project/commit/06673a9e9b186a65f5eb60a59a4ee9afba6637d4
DIFF: https://github.com/llvm/llvm-project/commit/06673a9e9b186a65f5eb60a59a4ee9afba6637d4.diff
LOG: [libc++] Uglify non-standard member typedef const_reference in bitset (#121620)
According to
[[template.bitset.general]](https://eel.is/c++draft/template.bitset.general),
`std::bitset` is supposed to have only
one (public) member typedef, `reference`. However, libc++'s
implementation of `std::bitset` offers more that that. Specifically, it
offers a public typedef `const_reference` and two private typedefs
`size_type` and `difference_type`. These non-standard member typedefs,
despite being private, can cause potential ambiguities in name lookup in
user-defined classes, as demonstrated in issue #121618.
Fixing the public member typedef `const_reference` is straightforward:
we can simply replace it with an `__ugly_name` such as
`__const_reference`. However, fixing the private member typedefs
`size_type` and `difference_type` is not so straightforward as they are
required by the `__bit_iterator` class and the corresponding algorithms
optimized for `__bit_iterator`s (e.g., `ranges::fill`).
This PR fixes the member typedef `const_reference` by using uglified
name for it. Further work will be undertaken to address `size_type` and
`difference_type`.
Follows up #80706, #111127, and #112843,
Added:
Modified:
libcxx/docs/ReleaseNotes/20.rst
libcxx/include/bitset
libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp
libcxx/test/std/utilities/template.bitset/bitset.members/nonstdmem.uglified.compile.pass.cpp
Removed:
################################################################################
diff --git a/libcxx/docs/ReleaseNotes/20.rst b/libcxx/docs/ReleaseNotes/20.rst
index ecfbaa5b7a3754..793b172a24af08 100644
--- a/libcxx/docs/ReleaseNotes/20.rst
+++ b/libcxx/docs/ReleaseNotes/20.rst
@@ -125,9 +125,10 @@ Deprecations and Removals
supported as an extension anymore, please migrate any code that uses e.g. ``std::vector<const T>`` to be
standards conforming.
-- Non-conforming member typedefs ``base``, ``iterator`` and ``const_iterator`` of ``std::bitset``, and member typedef
- ``base`` of ``std::forward_list`` and ``std::list`` are removed. Previously, they were private but could cause
- ambiguity in name lookup. Code that expects such ambiguity will possibly not compile in LLVM 20.
+- Non-conforming member typedefs ``base``, ``iterator``, ``const_iterator``, and ``const_reference`` of ``std::bitset``,
+ and member typedef ``base`` of ``std::forward_list`` and ``std::list`` are removed. Previously, these member typedefs
+ (except ``const_reference``) were private but could cause ambiguity in name lookup. Code that expects such ambiguity
+ will possibly not compile in LLVM 20.
- The function ``__libcpp_verbose_abort()`` is now ``noexcept``, to match ``std::terminate()``. (The combination of
``noexcept`` and ``[[noreturn]]`` has special significance for function effects analysis.) For backwards compatibility,
diff --git a/libcxx/include/bitset b/libcxx/include/bitset
index 919d2a0f07e096..c16635dc8092cd 100644
--- a/libcxx/include/bitset
+++ b/libcxx/include/bitset
@@ -189,7 +189,7 @@ protected:
__storage_type __first_[_N_words];
typedef __bit_reference<__bitset> reference;
- typedef __bit_const_reference<__bitset> const_reference;
+ typedef __bit_const_reference<__bitset> __const_reference;
typedef __bit_iterator<__bitset, false> __iterator;
typedef __bit_iterator<__bitset, true> __const_iterator;
@@ -199,8 +199,8 @@ protected:
_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 __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);
@@ -451,7 +451,7 @@ protected:
__storage_type __first_;
typedef __bit_reference<__bitset> reference;
- typedef __bit_const_reference<__bitset> const_reference;
+ typedef __bit_const_reference<__bitset> __const_reference;
typedef __bit_iterator<__bitset, false> __iterator;
typedef __bit_iterator<__bitset, true> __const_iterator;
@@ -461,8 +461,8 @@ protected:
_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 __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);
@@ -566,7 +566,7 @@ protected:
friend struct __bit_array<__bitset>;
typedef __bit_reference<__bitset> reference;
- typedef __bit_const_reference<__bitset> const_reference;
+ typedef __bit_const_reference<__bitset> __const_reference;
typedef __bit_iterator<__bitset, false> __iterator;
typedef __bit_iterator<__bitset, true> __const_iterator;
@@ -576,8 +576,8 @@ protected:
_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 __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);
@@ -619,7 +619,7 @@ public:
public:
typedef typename __base::reference reference;
- typedef typename __base::const_reference const_reference;
+ typedef typename __base::__const_reference __const_reference;
// 23.3.5.1 constructors:
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bitset() _NOEXCEPT {}
@@ -689,7 +689,7 @@ public:
return __base::__make_ref(__p);
}
# else
- _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference operator[](size_t __p) const {
+ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __const_reference operator[](size_t __p) const {
_LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__p < _Size, "bitset::operator[] index out of bounds");
return __base::__make_ref(__p);
}
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp
index 77eb9056bc6d99..bb7e10afc62ea9 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp
@@ -8,6 +8,8 @@
// constexpr bool operator[](size_t pos) const; // constexpr since C++23
+// XFAIL: FROZEN-CXX03-HEADERS-FIXME
+
#include <bitset>
#include <cassert>
#include <cstddef>
@@ -18,17 +20,17 @@
template <std::size_t N>
TEST_CONSTEXPR_CXX23 void test_index_const() {
- std::vector<std::bitset<N> > const cases = get_test_cases<N>();
- for (std::size_t c = 0; c != cases.size(); ++c) {
- std::bitset<N> const v = cases[c];
- if (v.size() > 0) {
- assert(v[N/2] == v.test(N/2));
- }
+ std::vector<std::bitset<N> > const cases = get_test_cases<N>();
+ for (std::size_t c = 0; c != cases.size(); ++c) {
+ std::bitset<N> const v = cases[c];
+ if (v.size() > 0) {
+ assert(v[N / 2] == v.test(N / 2));
}
+ }
#if !defined(_LIBCPP_VERSION) || defined(_LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL)
- ASSERT_SAME_TYPE(decltype(cases[0][0]), bool);
+ ASSERT_SAME_TYPE(decltype(cases[0][0]), bool);
#else
- ASSERT_SAME_TYPE(decltype(cases[0][0]), typename std::bitset<N>::const_reference);
+ ASSERT_SAME_TYPE(decltype(cases[0][0]), typename std::bitset<N>::__const_reference);
#endif
}
@@ -43,10 +45,10 @@ TEST_CONSTEXPR_CXX23 bool test() {
test_index_const<65>();
std::bitset<1> set_;
- set_[0] = false;
+ set_[0] = false;
const auto& set = set_;
- auto b = set[0];
- set_[0] = true;
+ auto b = set[0];
+ set_[0] = true;
#if !defined(_LIBCPP_VERSION) || defined(_LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL)
assert(!b);
#else
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/nonstdmem.uglified.compile.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/nonstdmem.uglified.compile.pass.cpp
index ae3ac819b1f9c6..ee5c64f9df5c74 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/nonstdmem.uglified.compile.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/nonstdmem.uglified.compile.pass.cpp
@@ -8,10 +8,11 @@
// <bitset>
-// This test ensures that we don't use a non-uglified name 'iterator',
-// 'const_iterator', and 'base' in the implementation of bitset.
+// This test ensures that we don't use a non-uglified name 'base', 'iterator',
+// 'const_iterator', and `const_reference` in the implementation of bitset.
//
// See https://github.com/llvm/llvm-project/issues/111125.
+// See https://github.com/llvm/llvm-project/issues/121618.
// XFAIL: FROZEN-CXX03-HEADERS-FIXME
@@ -23,6 +24,7 @@ struct my_base {
typedef int* iterator;
typedef const int* const_iterator;
typedef my_base base;
+ typedef const int& const_reference;
};
template <std::size_t N>
@@ -57,3 +59,13 @@ static_assert(std::is_same<my_derived<32>::base, my_base>::value, "");
static_assert(std::is_same<my_derived<48>::base, my_base>::value, "");
static_assert(std::is_same<my_derived<64>::base, my_base>::value, "");
static_assert(std::is_same<my_derived<96>::base, my_base>::value, "");
+
+static_assert(std::is_same<my_derived<0>::const_reference, const int&>::value, "");
+static_assert(std::is_same<my_derived<1>::const_reference, const int&>::value, "");
+static_assert(std::is_same<my_derived<8>::const_reference, const int&>::value, "");
+static_assert(std::is_same<my_derived<12>::const_reference, const int&>::value, "");
+static_assert(std::is_same<my_derived<16>::const_reference, const int&>::value, "");
+static_assert(std::is_same<my_derived<32>::const_reference, const int&>::value, "");
+static_assert(std::is_same<my_derived<48>::const_reference, const int&>::value, "");
+static_assert(std::is_same<my_derived<64>::const_reference, const int&>::value, "");
+static_assert(std::is_same<my_derived<96>::const_reference, const int&>::value, "");
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