From: Jonathan Wakely Date: Wed, 28 Apr 2021 14:56:04 +0000 (+0100) Subject: libstdc++: Define __cpp_lib_constexpr_string macro X-Git-Tag: releases/gcc-8.5.0~38 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=89ae54e088e184016bf7f72c64c4933f9f3c188d;p=thirdparty%2Fgcc.git libstdc++: Define __cpp_lib_constexpr_string macro As noted in r11-1339-gb6ab9ecd550227684643b41e9e33a4d3466724d8 we define a non-standard __cpp_lib_constexpr_char_traits feature test macro to indicate support for P0426R1 and P1032R1. At some point last year the __cpp_lib_constexpr_string macro was retconned to indicate support for those papers. This adds the new macro (which we didn't previously define, because it referred to P0980R1 "Making std::string constexpr" which we don't support). libstdc++-v3/ChangeLog: * include/bits/basic_string.h (__cpp_lib_constexpr_string): Define. * testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc: Check for __cpp_lib_constexpr_string. (cherry picked from commit 3da80ed7efd582575e7850a403ce693ec882d087) --- diff --git a/libstdc++-v3/include/bits/basic_string.h b/libstdc++-v3/include/bits/basic_string.h index 0f5d398fcf24..0be11c0c444c 100644 --- a/libstdc++-v3/include/bits/basic_string.h +++ b/libstdc++-v3/include/bits/basic_string.h @@ -48,11 +48,12 @@ # include #endif - namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION +#define __cpp_lib_constexpr_string 201611L + #if _GLIBCXX_USE_CXX11_ABI _GLIBCXX_BEGIN_NAMESPACE_CXX11 /** diff --git a/libstdc++-v3/testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc b/libstdc++-v3/testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc index 87ea4d89a623..6a5ea249752b 100644 --- a/libstdc++-v3/testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc +++ b/libstdc++-v3/testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc @@ -73,6 +73,13 @@ template return true; } +#ifndef __cpp_lib_constexpr_string +# error Feature-test macro for constexpr char_traits is missing +#elif __cpp_lib_constexpr_string < 201611 +# error Feature-test macro for constexpr char_traits has the wrong value +#endif + +// We also provide this non-standard macro for P0426R1. #ifndef __cpp_lib_constexpr_char_traits # error Feature-test macro for constexpr char_traits is missing #elif __cpp_lib_constexpr_char_traits != 201611