From 5388a43f6a3f348929292998bd6d0c1da6f006de Mon Sep 17 00:00:00 2001 From: Marek Polacek Date: Thu, 22 Jun 2023 16:56:26 -0400 Subject: c++: Add support for -std={c,gnu}++2{c,6} It seems prudent to add C++26 now that the first C++26 papers have been approved. I followed commit r11-6920 as well as r8-3237. Since C++23 is essentially finished and its __cplusplus value has settled to 202302L, I've updated cpp_init_builtins and marked -std=c++2b Undocumented and made -std=c++23 no longer Undocumented. As for __cplusplus, I've chosen 202400L: $ xg++ -std=c++26 -dM -E -x c++ - < /dev/null | grep cplusplus #define __cplusplus 202400L I've verified the patch with a simple test, exercising the new directives. Don't forget to update your GXX_TESTSUITE_STDS! This patch does not add -Wc++26-extensions. gcc/c-family/ChangeLog: * c-common.h (cxx_dialect): Add cxx26 as a dialect. * c-opts.cc (set_std_cxx26): New. (c_common_handle_option): Set options when -std={c,gnu}++2{c,6} is enabled. (c_common_post_options): Adjust comments. * c.opt: Add options for -std=c++26, std=c++2c, -std=gnu++26, and -std=gnu++2c. (std=c++2b): Mark as Undocumented. (std=c++23): No longer Undocumented. gcc/ChangeLog: * doc/cpp.texi (__cplusplus): Document value for -std=c++26 and -std=gnu++26. Document that for C++23, its value is 202302L. * doc/invoke.texi: Document -std=c++26 and -std=gnu++26. * dwarf2out.cc (highest_c_language): Handle GNU C++26. (gen_compile_unit_die): Likewise. libcpp/ChangeLog: * include/cpplib.h (c_lang): Add CXX26 and GNUCXX26. * init.cc (lang_defaults): Add rows for CXX26 and GNUCXX26. (cpp_init_builtins): Set __cplusplus to 202400L for C++26. Set __cplusplus to 202302L for C++23. gcc/testsuite/ChangeLog: * lib/target-supports.exp (check_effective_target_c++23): Return 1 also if check_effective_target_c++26. (check_effective_target_c++23_down): New. (check_effective_target_c++26_only): New. (check_effective_target_c++26): New. * g++.dg/cpp23/cplusplus.C: Adjust expected value. * g++.dg/cpp26/cplusplus.C: New test. --- gcc/doc/cpp.texi | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'gcc/doc/cpp.texi') diff --git a/gcc/doc/cpp.texi b/gcc/doc/cpp.texi index b0a2ce3..3f492b3 100644 --- a/gcc/doc/cpp.texi +++ b/gcc/doc/cpp.texi @@ -1908,9 +1908,10 @@ selected, the value of the macro is @code{201402L} for the 2014 C++ standard, @code{201703L} for the 2017 C++ standard, @code{202002L} for the 2020 C++ standard, -or an unspecified value strictly larger than @code{202002L} for the -experimental languages enabled by @option{-std=c++23} and -@option{-std=gnu++23}. +@code{202302L} for the 2023 C++ standard, +or an unspecified value strictly larger than @code{202302L} for the +experimental languages enabled by @option{-std=c++26} and +@option{-std=gnu++26}. @item __OBJC__ This macro is defined, with value 1, when the Objective-C compiler is in -- cgit v1.1