[libcxx-commits] [libcxx] e30a148 - [libc++] Remove generic char_traits implementation
Nikolas Klauser via libcxx-commits
libcxx-commits at lists.llvm.org
Wed Aug 9 15:55:34 PDT 2023
Author: Nikolas Klauser
Date: 2023-08-09T15:55:28-07:00
New Revision: e30a148b098d462d0267c479cd9e4783363c2761
URL: https://github.com/llvm/llvm-project/commit/e30a148b098d462d0267c479cd9e4783363c2761
DIFF: https://github.com/llvm/llvm-project/commit/e30a148b098d462d0267c479cd9e4783363c2761.diff
LOG: [libc++] Remove generic char_traits implementation
This has been deprecated and should be removed now.
Reviewed By: #libc, Mordante
Spies: Mordante, libcxx-commits
Differential Revision: https://reviews.llvm.org/D157058
Added:
Modified:
libcxx/docs/ReleaseNotes/18.rst
libcxx/include/__string/char_traits.h
libcxx/test/std/utilities/format/format.formattable/concept.formattable.compile.pass.cpp
Removed:
libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.deprecated.verify.cpp
libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.pass.cpp
################################################################################
diff --git a/libcxx/docs/ReleaseNotes/18.rst b/libcxx/docs/ReleaseNotes/18.rst
index 08eefa7940fbfb..8f61227cd23fa9 100644
--- a/libcxx/docs/ReleaseNotes/18.rst
+++ b/libcxx/docs/ReleaseNotes/18.rst
@@ -47,6 +47,13 @@ Improvements and New Features
Deprecations and Removals
-------------------------
+- The base template for ``std::char_traits`` has been removed. If you are using
+ ``std::char_traits`` with types other than ``char``, ``wchar_t``, ``char8_t``,
+ ``char16_t``, ``char32_t`` or a custom character type for which you
+ specialized ``std::char_traits``, your code will no longer work. The Standard
+ does not mandate that a base template is provided, and such a base template is
+ bound to be incorrect for some types, which could previously cause unexpected
+ behavior while going undetected.
Upcoming Deprecations and Removals
----------------------------------
@@ -54,15 +61,6 @@ Upcoming Deprecations and Removals
LLVM 18
~~~~~~~
-- The base template for ``std::char_traits`` has been marked as deprecated and
- will be removed in LLVM 18. If you are using ``std::char_traits`` with types
- other than ``char``, ``wchar_t``, ``char8_t``, ``char16_t``, ``char32_t`` or
- a custom character type for which you specialized ``std::char_traits``, your code
- will stop working when we remove the base template. The Standard does not
- mandate that a base template is provided, and such a base template is bound
- to be incorrect for some types, which could currently cause unexpected
- behavior while going undetected.
-
- The ``_LIBCPP_AVAILABILITY_CUSTOM_VERBOSE_ABORT_PROVIDED`` macro will not be honored anymore in LLVM 18.
Please see the updated documentation about the safe libc++ mode and in particular the ``_LIBCPP_VERBOSE_ABORT``
macro for details.
@@ -79,4 +77,3 @@ ABI Affecting Changes
Build System Changes
--------------------
-
diff --git a/libcxx/include/__string/char_traits.h b/libcxx/include/__string/char_traits.h
index c201fc9a1cda77..baf2d2346a5960 100644
--- a/libcxx/include/__string/char_traits.h
+++ b/libcxx/include/__string/char_traits.h
@@ -71,106 +71,6 @@ exposition-only to document what members a char_traits specialization should pro
};
*/
-//
-// Temporary extension to provide a base template for std::char_traits.
-// TODO(LLVM-18): Remove this class.
-//
-template <class _CharT>
-struct _LIBCPP_DEPRECATED_("char_traits<T> for T not equal to char, wchar_t, char8_t, char16_t or char32_t is non-standard and is provided for a temporary period. It will be removed in LLVM 18, so please migrate off of it.")
- char_traits
-{
- using char_type = _CharT;
- using int_type = int;
- using off_type = streamoff;
- using pos_type = streampos;
- using state_type = mbstate_t;
-
- static inline void _LIBCPP_CONSTEXPR_SINCE_CXX17 _LIBCPP_HIDE_FROM_ABI
- assign(char_type& __c1, const char_type& __c2) _NOEXCEPT {__c1 = __c2;}
- static inline _LIBCPP_HIDE_FROM_ABI _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 __c1 < __c2;}
-
- static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17
- int compare(const char_type* __s1, const char_type* __s2, size_t __n) {
- for (; __n; --__n, ++__s1, ++__s2)
- {
- if (lt(*__s1, *__s2))
- return -1;
- if (lt(*__s2, *__s1))
- return 1;
- }
- return 0;
- }
- _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR_SINCE_CXX17
- size_t length(const char_type* __s) {
- size_t __len = 0;
- for (; !eq(*__s, char_type(0)); ++__s)
- ++__len;
- return __len;
- }
- _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR_SINCE_CXX17
- const char_type* find(const char_type* __s, size_t __n, const char_type& __a) {
- for (; __n; --__n)
- {
- if (eq(*__s, __a))
- return __s;
- ++__s;
- }
- return nullptr;
- }
- static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
- char_type* move(char_type* __s1, const char_type* __s2, size_t __n) {
- if (__n == 0) return __s1;
- char_type* __r = __s1;
- if (__s1 < __s2)
- {
- for (; __n; --__n, ++__s1, ++__s2)
- assign(*__s1, *__s2);
- }
- else if (__s2 < __s1)
- {
- __s1 += __n;
- __s2 += __n;
- for (; __n; --__n)
- assign(*--__s1, *--__s2);
- }
- return __r;
- }
- _LIBCPP_INLINE_VISIBILITY
- static _LIBCPP_CONSTEXPR_SINCE_CXX20
- char_type* copy(char_type* __s1, const char_type* __s2, size_t __n) {
- if (!__libcpp_is_constant_evaluated()) {
- _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(
- __s2 < __s1 || __s2 >= __s1 + __n, "char_traits::copy overlapped range");
- }
- char_type* __r = __s1;
- for (; __n; --__n, ++__s1, ++__s2)
- assign(*__s1, *__s2);
- return __r;
- }
- _LIBCPP_INLINE_VISIBILITY
- static _LIBCPP_CONSTEXPR_SINCE_CXX20
- char_type* assign(char_type* __s, size_t __n, char_type __a) {
- char_type* __r = __s;
- for (; __n; --__n, ++__s)
- assign(*__s, __a);
- return __r;
- }
-
- 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(__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);}
-};
-
// char_traits<char>
template <>
diff --git a/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.deprecated.verify.cpp b/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.deprecated.verify.cpp
deleted file mode 100644
index ec6f34ef5462e6..00000000000000
--- a/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.deprecated.verify.cpp
+++ /dev/null
@@ -1,21 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// <string>
-
-// template<> struct char_traits<T> for arbitrary T
-
-// Make sure we issue deprecation warnings.
-
-#include <string>
-
-void f() {
- std::char_traits<unsigned char> t1; (void)t1; // expected-warning{{'char_traits<unsigned char>' is deprecated}}
- std::char_traits<signed char> t2; (void)t2; // expected-warning{{'char_traits<signed char>' is deprecated}}
- std::char_traits<unsigned long> t3; (void)t3; // expected-warning{{'char_traits<unsigned long>' is deprecated}}
-}
diff --git a/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.pass.cpp b/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.pass.cpp
deleted file mode 100644
index c2de29d22b2fe4..00000000000000
--- a/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.pass.cpp
+++ /dev/null
@@ -1,146 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// <string>
-
-// template<> struct char_traits<T> for arbitrary T
-
-// Non-standard but provided temporarily for users to migrate.
-
-// ADDITIONAL_COMPILE_FLAGS: -Wno-deprecated
-
-#include <string>
-#include <cassert>
-#include <type_traits>
-
-#include "test_macros.h"
-
-template <class Char>
-TEST_CONSTEXPR_CXX20 bool test() {
- static_assert(std::is_same<typename std::char_traits<Char>::char_type, Char>::value, "");
- static_assert(std::is_same<typename std::char_traits<Char>::int_type, int>::value, "");
- static_assert(std::is_same<typename std::char_traits<Char>::off_type, std::streamoff>::value, "");
- static_assert(std::is_same<typename std::char_traits<Char>::pos_type, std::streampos>::value, "");
- static_assert(std::is_same<typename std::char_traits<Char>::state_type, std::mbstate_t>::value, "");
-
- assert(std::char_traits<Char>::to_int_type(Char('a')) == Char('a'));
- assert(std::char_traits<Char>::to_int_type(Char('A')) == Char('A'));
- assert(std::char_traits<Char>::to_int_type(0) == 0);
-
- assert(std::char_traits<Char>::to_char_type(Char('a')) == Char('a'));
- assert(std::char_traits<Char>::to_char_type(Char('A')) == Char('A'));
- assert(std::char_traits<Char>::to_char_type(0) == 0);
-
- assert(std::char_traits<Char>::eof() == EOF);
-
- assert(std::char_traits<Char>::not_eof(Char('a')) == Char('a'));
- assert(std::char_traits<Char>::not_eof(Char('A')) == Char('A'));
- assert(std::char_traits<Char>::not_eof(0) == 0);
- assert(std::char_traits<Char>::not_eof(std::char_traits<Char>::eof()) !=
- std::char_traits<Char>::eof());
-
- assert(std::char_traits<Char>::lt(Char('\0'), Char('A')) == (Char('\0') < Char('A')));
- assert(std::char_traits<Char>::lt(Char('A'), Char('\0')) == (Char('A') < Char('\0')));
- assert(std::char_traits<Char>::lt(Char('a'), Char('a')) == (Char('a') < Char('a')));
- assert(std::char_traits<Char>::lt(Char('A'), Char('a')) == (Char('A') < Char('a')));
- assert(std::char_traits<Char>::lt(Char('a'), Char('A')) == (Char('a') < Char('A')));
-
- assert( std::char_traits<Char>::eq(Char('a'), Char('a')));
- assert(!std::char_traits<Char>::eq(Char('a'), Char('A')));
-
- assert( std::char_traits<Char>::eq_int_type(Char('a'), Char('a')));
- assert(!std::char_traits<Char>::eq_int_type(Char('a'), Char('A')));
- assert(!std::char_traits<Char>::eq_int_type(std::char_traits<Char>::eof(), Char('A')));
- assert( std::char_traits<Char>::eq_int_type(std::char_traits<Char>::eof(), std::char_traits<Char>::eof()));
-
- {
- Char s1[] = {1, 2, 3, 0};
- Char s2[] = {0};
- assert(std::char_traits<Char>::length(s1) == 3);
- assert(std::char_traits<Char>::length(s2) == 0);
- }
-
- {
- Char s1[] = {1, 2, 3};
- assert(std::char_traits<Char>::find(s1, 3, Char(1)) == s1);
- assert(std::char_traits<Char>::find(s1, 3, Char(2)) == s1+1);
- assert(std::char_traits<Char>::find(s1, 3, Char(3)) == s1+2);
- assert(std::char_traits<Char>::find(s1, 3, Char(4)) == 0);
- assert(std::char_traits<Char>::find(s1, 3, Char(0)) == 0);
- assert(std::char_traits<Char>::find(NULL, 0, Char(0)) == 0);
- }
-
- {
- Char s1[] = {1, 2, 3};
- Char s2[3] = {0};
- assert(std::char_traits<Char>::copy(s2, s1, 3) == s2);
- assert(s2[0] == Char(1));
- assert(s2[1] == Char(2));
- assert(s2[2] == Char(3));
- assert(std::char_traits<Char>::copy(NULL, s1, 0) == NULL);
- assert(std::char_traits<Char>::copy(s1, NULL, 0) == s1);
- }
-
- {
- Char s1[] = {1, 2, 3};
- assert(std::char_traits<Char>::move(s1, s1+1, 2) == s1);
- assert(s1[0] == Char(2));
- assert(s1[1] == Char(3));
- assert(s1[2] == Char(3));
- s1[2] = Char(0);
- assert(std::char_traits<Char>::move(s1+1, s1, 2) == s1+1);
- assert(s1[0] == Char(2));
- assert(s1[1] == Char(2));
- assert(s1[2] == Char(3));
- assert(std::char_traits<Char>::move(NULL, s1, 0) == NULL);
- assert(std::char_traits<Char>::move(s1, NULL, 0) == s1);
- }
-
- {
- Char s1[] = {0};
- assert(std::char_traits<Char>::compare(s1, s1, 0) == 0);
- assert(std::char_traits<Char>::compare(NULL, NULL, 0) == 0);
-
- Char s2[] = {1, 0};
- Char s3[] = {2, 0};
- assert(std::char_traits<Char>::compare(s2, s2, 1) == 0);
- assert(std::char_traits<Char>::compare(s2, s3, 1) < 0);
- assert(std::char_traits<Char>::compare(s3, s2, 1) > 0);
- }
-
- {
- Char s2[3] = {0};
- assert(std::char_traits<Char>::assign(s2, 3, Char(5)) == s2);
- assert(s2[0] == Char(5));
- assert(s2[1] == Char(5));
- assert(s2[2] == Char(5));
- assert(std::char_traits<Char>::assign(NULL, 0, Char(5)) == NULL);
- }
-
- {
- Char c = Char('\0');
- std::char_traits<Char>::assign(c, Char('a'));
- assert(c == Char('a'));
- }
-
- return true;
-}
-
-int main(int, char**) {
- test<unsigned char>();
- test<signed char>();
- test<unsigned long>();
-
-#if TEST_STD_VER > 17
- static_assert(test<unsigned char>());
- static_assert(test<signed char>());
- static_assert(test<unsigned long>());
-#endif
-
- return 0;
-}
diff --git a/libcxx/test/std/utilities/format/format.formattable/concept.formattable.compile.pass.cpp b/libcxx/test/std/utilities/format/format.formattable/concept.formattable.compile.pass.cpp
index eadf10c95de994..1f16eeca20aca9 100644
--- a/libcxx/test/std/utilities/format/format.formattable/concept.formattable.compile.pass.cpp
+++ b/libcxx/test/std/utilities/format/format.formattable/concept.formattable.compile.pass.cpp
@@ -412,6 +412,4 @@ void test() {
test<char8_t>();
test<char16_t>();
test<char32_t>();
-
- test<int>();
}
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