On Fri, Jun 12, 2026 at 05:54:44PM +0200, Jakub Jelinek wrote: > Hi! > > The following patch adds a new -std= option arguments for C++29 and > changes __cplusplus value for C++26 from 202400L to 202603L. > > Ok for trunk?
Looks OK (not an approval) to me (provided the 202603L value is now settled). > 2026-06-12 Jakub Jelinek <[email protected]> > > gcc/ > * doc/invoke.texi (-std=c++2d, -std=c++29, -std=gnu++2d, > -std=gnu++29): Document. > * doc/cpp.texi: Adjust expected __cplusplus value for -std=c++26, > document value for -std=c++29. > * dwarf2out.cc (highest_c_language): Handle C++29. > (gen_compile_unit_die): Likewise. Adjust lversion for C++26. > gcc/c-family/ > * c-common.h (enum cxx_dialect): Add cxx29. > * c-opts.cc (set_std_cxx29): New function. > (c_common_handle_option): Handle -std=c++2d, -std=c++29, -std=gnu++2d > and -std=gnu++29. > * c.opt (std=c++2d, std=c++29, std=gnu++2d, std=gnu++29): New. > gcc/testsuite/ > * g++.dg/cpp26/cplusplus.C: Expect __cplusplus == 202603L. > * g++.dg/cpp29/cplusplus.C: New test. > * g++.dg/cpp29/feat-cxx29.C: New test. > * lib/target-supports.exp (check_effective_target_c++26): Also > true for C++29. > (check_effective_target_c++26_down, check_effective_target_c++29_only, > check_effective_target_c++29): New procedures. > * lib/g++-dg.exp (g++-std-flags): Add 29 to the list too. > libcpp/ > * include/cpplib.h (enum c_lang): Add CLK_GNUCXX29 and CLK_CXX29. > * init.cc (lang_defaults): Add CLK_GNUCXX29 and CLK_CXX29 row. > (cpp_init_builtins): Change __cplusplus value for C++26 from 202400L > to 202603L and set __cplusplus value for C++29 to 202700L. > > --- gcc/c-family/c-common.h.jj 2026-06-05 10:39:31.134351137 +0200 > +++ gcc/c-family/c-common.h 2026-06-12 17:00:25.426903046 +0200 > @@ -751,7 +751,9 @@ enum cxx_dialect { > /* C++23 */ > cxx23, > /* C++26 */ > - cxx26 > + cxx26, > + /* C++29 */ > + cxx29 > }; > > /* The C++ dialect being used. C++20 is the default. */ > --- gcc/c-family/c-opts.cc.jj 2026-05-30 17:45:09.345110280 +0200 > +++ gcc/c-family/c-opts.cc 2026-06-12 17:25:31.330852780 +0200 > @@ -118,6 +118,7 @@ static void set_std_cxx17 (int); > static void set_std_cxx20 (int); > static void set_std_cxx23 (int); > static void set_std_cxx26 (int); > +static void set_std_cxx29 (int); > static void set_std_c89 (int, int); > static void set_std_c99 (int); > static void set_std_c11 (int); > @@ -701,6 +702,12 @@ c_common_handle_option (size_t scode, co > set_std_cxx26 (code == OPT_std_c__26 /* ISO */); > break; > > + case OPT_std_c__29: > + case OPT_std_gnu__29: > + if (!preprocessing_asm_p) > + set_std_cxx29 (code == OPT_std_c__29 /* ISO */); > + break; > + > case OPT_std_c90: > case OPT_std_iso9899_199409: > if (!preprocessing_asm_p) > @@ -2095,6 +2102,22 @@ set_std_cxx26 (int iso) > lang_hooks.name = "GNU C++26"; > } > > +/* Set the C++ 2029 standard (without GNU extensions if ISO). */ > +static void > +set_std_cxx29 (int iso) > +{ > + cpp_set_lang (parse_in, iso ? CLK_CXX29 : CLK_GNUCXX29); > + flag_no_gnu_keywords = iso; > + flag_no_nonansi_builtin = iso; > + flag_iso = iso; > + /* C++29 includes the C11 standard library. */ > + flag_isoc94 = 1; > + flag_isoc99 = 1; > + flag_isoc11 = 1; > + cxx_dialect = cxx29; > + lang_hooks.name = "GNU C++29"; > +} > + > /* Args to -d specify what to dump. Silently ignore > unrecognized options; they may be aimed at toplev.cc. */ > static void > --- gcc/c-family/c.opt.jj 2026-06-01 09:15:39.010605683 +0200 > +++ gcc/c-family/c.opt 2026-06-12 17:05:03.744184261 +0200 > @@ -2676,6 +2676,14 @@ std=c++26 > C++ ObjC++ Undocumented > Conform to the ISO 2026 C++ draft standard (experimental and incomplete > support). > > +std=c++2d > +C++ ObjC++ Alias(std=c++29) > +Conform to the ISO 2029 C++ draft standard (experimental and incomplete > support). > + > +std=c++29 > +C++ ObjC++ Undocumented > +Conform to the ISO 2029 C++ draft standard (experimental and incomplete > support). > + > std=c11 > C ObjC > Conform to the ISO 2011 C standard. > @@ -2778,6 +2786,14 @@ std=gnu++26 > C++ ObjC++ Undocumented > Conform to the ISO 2026 C++ draft standard with GNU extensions (experimental > and incomplete support). > > +std=gnu++2d > +C++ ObjC++ Alias(std=gnu++29) > +Conform to the ISO 2029 C++ draft standard with GNU extensions (experimental > and incomplete support). > + > +std=gnu++29 > +C++ ObjC++ Undocumented > +Conform to the ISO 2029 C++ draft standard with GNU extensions (experimental > and incomplete support). > + > std=gnu11 > C ObjC > Conform to the ISO 2011 C standard with GNU extensions. > --- gcc/doc/invoke.texi.jj 2026-06-10 17:42:21.458938285 +0200 > +++ gcc/doc/invoke.texi 2026-06-12 17:27:00.453670490 +0200 > @@ -2648,6 +2648,18 @@ change in incompatible ways in future re > GNU dialect of @option{-std=c++2c}. Support is highly experimental, > and will almost certainly change in incompatible ways in future > releases. > + > +@item c++2d > +@itemx c++29 > +The upcoming revision of the ISO C++ standard, planned for > +2029. Support is highly experimental, and will almost certainly > +change in incompatible ways in future releases. > + > +@item gnu++2d > +@itemx gnu++29 > +GNU dialect of @option{-std=c++2d}. Support is highly experimental, > +and will almost certainly change in incompatible ways in future > +releases. > @end table > > @opindex aux-info > --- gcc/doc/cpp.texi.jj 2026-06-09 10:19:34.527847828 +0200 > +++ gcc/doc/cpp.texi 2026-06-12 17:08:35.300367120 +0200 > @@ -1912,9 +1912,10 @@ selected, the value of the macro is > @code{201703L} for the 2017 C++ standard, > @code{202002L} for the 2020 C++ standard, > @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}. > +@code{202603L} for the 2026 C++ standard, > +or an unspecified value strictly larger than @code{202603L} for the > +experimental languages enabled by @option{-std=c++29} and > +@option{-std=gnu++29}. > > @item __OBJC__ > This macro is defined, with value 1, when the Objective-C compiler is in > --- gcc/testsuite/g++.dg/cpp26/cplusplus.C.jj 2026-03-27 10:17:15.650306001 > +0100 > +++ gcc/testsuite/g++.dg/cpp26/cplusplus.C 2026-06-12 17:15:00.831233282 > +0200 > @@ -1,3 +1,3 @@ > // { dg-do compile { target c++26_only } } > > -static_assert(__cplusplus > 202302L); > +static_assert(__cplusplus == 202603L); > --- gcc/testsuite/g++.dg/cpp29/cplusplus.C.jj 2026-06-12 17:15:32.774807913 > +0200 > +++ gcc/testsuite/g++.dg/cpp29/cplusplus.C 2026-06-12 17:16:32.290015391 > +0200 > @@ -0,0 +1,3 @@ > +// { dg-do compile { target c++29_only } } > + > +static_assert(__cplusplus > 202603L); > --- gcc/testsuite/g++.dg/cpp29/feat-cxx29.C.jj 2026-06-12 > 17:15:48.882593418 +0200 > +++ gcc/testsuite/g++.dg/cpp29/feat-cxx29.C 2026-06-12 17:16:03.543398189 > +0200 > @@ -0,0 +1,660 @@ > +// { dg-options "-std=c++29 -I${srcdir}/g++.dg/cpp1y > -I${srcdir}/g++.dg/cpp1y/testinc" } > +// { dg-skip-if "requires hosted libstdc++ for complex" { ! hostedlib } } > + > +// C++98 features: > + > +#ifndef __cpp_rtti > +# error "__cpp_rtti" > +#elif __cpp_rtti != 199711 > +# error "__cpp_rtti != 199711" > +#endif > + > +#ifndef __cpp_exceptions > +# error "__cpp_exceptions" > +#elif __cpp_exceptions != 199711 > +# error "__cpp_exceptions != 199711" > +#endif > + > +// C++11 features: > + > +#ifndef __cpp_raw_strings > +# error "__cpp_raw_strings" > +#elif __cpp_raw_strings != 200710 > +# error "__cpp_raw_strings != 200710" > +#endif > + > +#ifndef __cpp_unicode_literals > +# error "__cpp_unicode_literals" > +#elif __cpp_unicode_literals != 200710 > +# error "__cpp_unicode_literals != 200710" > +#endif > + > +#ifndef __cpp_user_defined_literals > +# error "__cpp_user_defined_literals" > +#elif __cpp_user_defined_literals != 200809 > +# error "__cpp_user_defined_literals != 200809" > +#endif > + > +#ifndef __cpp_lambdas > +# error "__cpp_lambdas" > +#elif __cpp_lambdas != 200907 > +# error "__cpp_lambdas != 200907" > +#endif > + > +#ifndef __cpp_range_based_for > +# error "__cpp_range_based_for" > +#elif __cpp_range_based_for != 202211 > +# error "__cpp_range_based_for != 202211" > +#endif > + > +#ifndef __cpp_decltype > +# error "__cpp_decltype" > +#elif __cpp_decltype != 200707 > +# error "__cpp_decltype != 200707" > +#endif > + > +#ifndef __cpp_attributes > +# error "__cpp_attributes" > +#elif __cpp_attributes != 200809 > +# error "__cpp_attributes != 200809" > +#endif > + > +#ifndef __cpp_rvalue_references > +# error "__cpp_rvalue_references" > +#elif __cpp_rvalue_references != 200610 > +# error "__cpp_rvalue_references != 200610" > +#endif > + > +#ifndef __cpp_variadic_templates > +# error "__cpp_variadic_templates" > +#elif __cpp_variadic_templates != 200704 > +# error "__cpp_variadic_templates != 200704" > +#endif > + > +#ifndef __cpp_initializer_lists > +# error "__cpp_initializer_lists" > +#elif __cpp_initializer_lists != 200806 > +# error "__cpp_initializer_lists != 200806" > +#endif > + > +#ifndef __cpp_delegating_constructors > +# error "__cpp_delegating_constructors" > +#elif __cpp_delegating_constructors != 200604 > +# error "__cpp_delegating_constructors != 200604" > +#endif > + > +#ifndef __cpp_nsdmi > +# error "__cpp_nsdmi" > +#elif __cpp_nsdmi != 200809 > +# error "__cpp_nsdmi != 200809" > +#endif > + > +#ifndef __cpp_inheriting_constructors > +# error "__cpp_inheriting_constructors" > +#elif __cpp_inheriting_constructors!= 201511 > +# error "__cpp_inheriting_constructors != 201511" > +#endif > + > +#ifndef __cpp_ref_qualifiers > +# error "__cpp_ref_qualifiers" > +#elif __cpp_ref_qualifiers != 200710 > +# error "__cpp_ref_qualifiers != 200710" > +#endif > + > +#ifndef __cpp_alias_templates > +# error "__cpp_alias_templates" > +#elif __cpp_alias_templates != 200704 > +# error "__cpp_alias_templates != 200704" > +#endif > + > +#ifndef __cpp_threadsafe_static_init > +# error "__cpp_threadsafe_static_init" > +#elif __cpp_threadsafe_static_init != 200806 > +# error "__cpp_threadsafe_static_init != 200806" > +#endif > + > +// C++14 features: > + > +#ifndef __cpp_binary_literals > +# error "__cpp_binary_literals" > +#elif __cpp_binary_literals != 201304 > +# error "__cpp_binary_literals != 201304" > +#endif > + > +#ifndef __cpp_init_captures > +# error "__cpp_init_captures" > +#elif __cpp_init_captures != 201803 > +# error "__cpp_init_captures != 201803" > +#endif > + > +#ifndef __cpp_generic_lambdas > +# error "__cpp_generic_lambdas" > +#elif __cpp_generic_lambdas != 201707 > +# error "__cpp_generic_lambdas != 201707" > +#endif > + > +#ifndef __cpp_constexpr > +# error "__cpp_constexpr" > +#elif __cpp_constexpr != 202406L > +# error "__cpp_constexpr != 202406L" > +#endif > + > +#ifndef __cpp_decltype_auto > +# error "__cpp_decltype_auto" > +#elif __cpp_decltype_auto != 201304 > +# error "__cpp_decltype_auto != 201304" > +#endif > + > +#ifndef __cpp_return_type_deduction > +# error "__cpp_return_type_deduction" > +#elif __cpp_return_type_deduction != 201304 > +# error "__cpp_return_type_deduction != 201304" > +#endif > + > +#ifndef __cpp_aggregate_nsdmi > +# error "__cpp_aggregate_nsdmi" > +#elif __cpp_aggregate_nsdmi != 201304 > +# error "__cpp_aggregate_nsdmi != 201304" > +#endif > + > +#ifndef __cpp_variable_templates > +# error "__cpp_variable_templates" > +#elif __cpp_variable_templates != 201304 > +# error "__cpp_variable_templates != 201304" > +#endif > + > +#ifndef __cpp_digit_separators > +# error "__cpp_digit_separators" > +#elif __cpp_digit_separators != 201309 > +# error "__cpp_digit_separators != 201309" > +#endif > + > +#ifndef __cpp_sized_deallocation > +# error "__cpp_sized_deallocation" > +#elif __cpp_sized_deallocation != 201309 > +# error "__cpp_sized_deallocation != 201309" > +#endif > + > +// GNU VLA support: > + > +#ifndef __cpp_runtime_arrays > +# error "__cpp_runtime_arrays" > +#elif __cpp_runtime_arrays != 198712 > +# error "__cpp_runtime_arrays != 198712" > +#endif > + > +// C++11 attributes: > + > +#ifdef __has_cpp_attribute > +# if ! __has_cpp_attribute(noreturn) > +# error "__has_cpp_attribute(noreturn)" > +# elif __has_cpp_attribute(noreturn) != 200809 > +# error "__has_cpp_attribute(noreturn) != 200809" > +# endif > +#else > +# error "__has_cpp_attribute" > +#endif > + > +// Attribute carries_dependency not in yet. > +//#ifdef __has_cpp_attribute > +//# if ! __has_cpp_attribute(carries_dependency) > +//# error "__has_cpp_attribute(carries_dependency)" > +//# elif __has_cpp_attribute(carries_dependency) != 200809 > +//# error "__has_cpp_attribute(carries_dependency) != 200809" > +//# endif > +//#else > +//# error "__has_cpp_attribute" > +//#endif > + > +// C++14 attributes: > + > +#ifdef __has_cpp_attribute > +# if ! __has_cpp_attribute(deprecated) > +# error "__has_cpp_attribute(deprecated)" > +# elif __has_cpp_attribute(deprecated) != 201309 > +# error "__has_cpp_attribute(deprecated) != 201309" > +# endif > +#else > +# error "__has_cpp_attribute" > +#endif > + > +// Include checks: > + > +// Check for __has_include macro. > +#ifndef __has_include > +# error "__has_include" > +#endif > + > +// Try known bracket header (use operator). > +#if __has_include (<complex>) > +#else > +# error "<complex>" > +#endif > + > +// Define and use a macro to invoke the operator. > +#define sluggo(TXT) __has_include(TXT) > + > +#if sluggo(<complex>) > +#else > +# error "<complex>" > +#endif > + > +#if ! sluggo(<complex>) > +# error "<complex>" > +#else > +#endif > + > +// Quoted complex.h should find at least the bracket version. > +#if __has_include("complex.h") > +#else > +# error "complex.h" > +#endif > + > +// Try known local quote header. > +#if __has_include("complex_literals.h") > +#else > +# error "\"complex_literals.h\"" > +#endif > + > +// Try nonexistent bracket header. > +#if __has_include(<stuff>) > +# error "<stuff>" > +#else > +#endif > + > +// Try nonexistent quote header. > +#if __has_include("phlegm") > +# error "\"phlegm\"" > +#else > +#endif > + > +// Test __has_include_next. > +#if __has_include("phoobhar.h") > +# include "phoobhar.h" > +#else > +# error "__has_include(\"phoobhar.h\")" > +#endif > + > +// Try a macro. > +#define COMPLEX_INC "complex.h" > +#if __has_include(COMPLEX_INC) > +#else > +# error COMPLEX_INC > +#endif > + > +// Realistic use of __has_include. > +#if __has_include(<array>) > +# define STD_ARRAY 1 > +# include <array> > + template<typename _Tp, std::size_t _Num> > + using array = std::array<_Tp, _Num>; > +#elif __has_include(<tr1/array>) > +# define TR1_ARRAY 1 > +# include <tr1/array> > + template<typename _Tp, std::size_t _Num> > + typedef std::tr1::array<_Tp, _Num> array; > +#endif > + > +// C++17 features: > + > +#ifndef __cpp_unicode_characters > +# error "__cpp_unicode_characters" > +#elif __cpp_unicode_characters != 201411 > +# error "__cpp_unicode_characters != 201411" > +#endif > + > +#ifndef __cpp_static_assert > +# error "__cpp_static_assert" > +#elif __cpp_static_assert != 202306 > +# error "__cpp_static_assert != 202306" > +#endif > + > +#ifndef __cpp_namespace_attributes > +# error "__cpp_namespace_attributes" > +#elif __cpp_namespace_attributes != 201411 > +# error "__cpp_namespace_attributes != 201411" > +#endif > + > +#ifndef __cpp_enumerator_attributes > +# error "__cpp_enumerator_attributes" > +#elif __cpp_enumerator_attributes != 201411 > +# error "__cpp_enumerator_attributes != 201411" > +#endif > + > +#ifndef __cpp_nested_namespace_definitions > +# error "__cpp_nested_namespace_definitions" > +#elif __cpp_nested_namespace_definitions != 201411 > +# error "__cpp_nested_namespace_definitions != 201411" > +#endif > + > +#ifndef __cpp_fold_expressions > +# error "__cpp_fold_expressions" > +#elif __cpp_fold_expressions != 201603 > +# error "__cpp_fold_expressions != 201603" > +#endif > + > +#ifndef __cpp_nontype_template_args > +# error "__cpp_nontype_template_args" > +#elif __cpp_nontype_template_args != 201911 > +# error "__cpp_nontype_template_args != 201911" > +#endif > + > +#ifndef __cpp_hex_float > +# error "__cpp_hex_float" > +#elif __cpp_hex_float != 201603 > +# error "__cpp_hex_float != 201603" > +#endif > + > +#ifndef __cpp_aggregate_bases > +# error "__cpp_aggregate_bases" > +#elif __cpp_aggregate_bases != 201603 > +# error "__cpp_aggregate_bases != 201603" > +#endif > + > +#ifndef __cpp_deduction_guides > +# error "__cpp_deduction_guides" > +#elif __cpp_deduction_guides != 202207 > +# error "__cpp_deduction_guides != 202207" > +#endif > + > +#ifndef __cpp_if_constexpr > +# error "__cpp_if_constexpr" > +#elif __cpp_if_constexpr != 201606 > +# error "__cpp_if_constexpr != 201606" > +#endif > + > +#ifndef __cpp_aligned_new > +# error "__cpp_aligned_new" > +#elif __cpp_aligned_new != 201606 > +# error "__cpp_aligned_new != 201606" > +#endif > + > +#ifndef __cpp_template_auto > +# error "__cpp_template_auto" > +#elif __cpp_template_auto != 201606 > +# error "__cpp_template_auto != 201606" > +#endif > + > +#ifndef __cpp_inline_variables > +# error "__cpp_inline_variables" > +#elif __cpp_inline_variables != 201606 > +# error "__cpp_inline_variables != 201606" > +#endif > + > +#ifndef __cpp_capture_star_this > +# error "__cpp_capture_star_this" > +#elif __cpp_capture_star_this != 201603 > +# error "__cpp_capture_star_this != 201603" > +#endif > + > +#ifndef __cpp_noexcept_function_type > +# error "__cpp_noexcept_function_type" > +#elif __cpp_noexcept_function_type != 201510 > +# error "__cpp_noexcept_function_type != 201510" > +#endif > + > +#ifndef __cpp_structured_bindings > +# error "__cpp_structured_bindings" > +#elif __cpp_structured_bindings != 202411 > +# error "__cpp_structured_bindings != 202411" > +#endif > + > +#ifndef __cpp_template_template_args > +# error "__cpp_template_template_args" > +#elif __cpp_template_template_args != 201611 > +# error "__cpp_template_template_args != 201611" > +#endif > + > +#ifndef __cpp_variadic_using > +# error "__cpp_variadic_using" > +#elif __cpp_variadic_using != 201611 > +# error "__cpp_variadic_using != 201611" > +#endif > + > +#ifndef __cpp_guaranteed_copy_elision > +# error "__cpp_guaranteed_copy_elision" > +#elif __cpp_guaranteed_copy_elision != 201606 > +# error "__cpp_guaranteed_copy_elision != 201606" > +#endif > + > +#ifndef __cpp_nontype_template_parameter_auto > +# error "__cpp_nontype_template_parameter_auto" > +#elif __cpp_nontype_template_parameter_auto != 201606 > +# error "__cpp_nontype_template_parameter_auto != 201606" > +#endif > + > +// C++20 features: > + > +#ifndef __cpp_conditional_explicit > +# error "__cpp_conditional_explicit" > +#elif __cpp_conditional_explicit != 201806 > +# error "__cpp_conditional_explicit != 201806" > +#endif > + > +#ifndef __cpp_nontype_template_parameter_class > +# error "__cpp_nontype_template_parameter_class" > +#elif __cpp_nontype_template_parameter_class != 201806 > +# error "__cpp_nontype_template_parameter_class != 201806" > +#endif > + > +#ifndef __cpp_impl_destroying_delete > +# error "__cpp_impl_destroying_delete" > +#elif __cpp_impl_destroying_delete != 201806 > +# error "__cpp_impl_destroying_delete != 201806" > +#endif > + > +#ifndef __cpp_constinit > +# error "__cpp_constinit" > +#elif __cpp_constinit != 201907 > +# error "__cpp_constinit != 201907" > +#endif > + > +#ifndef __cpp_constexpr_dynamic_alloc > +# error "__cpp_constexpr_dynamic_alloc" > +#elif __cpp_constexpr_dynamic_alloc != 201907 > +# error "__cpp_constexpr_dynamic_alloc != 201907" > +#endif > + > +#ifndef __cpp_aggregate_paren_init > +# error "__cpp_aggregate_paren_init" > +#elif __cpp_aggregate_paren_init != 201902 > +# error "__cpp_aggregate_paren_init != 201902" > +#endif > + > +#ifndef __cpp_char8_t > +# error "__cpp_char8_t" > +#elif __cpp_char8_t != 202207 > +# error "__cpp_char8_t != 202207" > +#endif > + > +#ifndef __cpp_designated_initializers > +# error "__cpp_designated_initializers" > +#elif __cpp_designated_initializers != 201707 > +# error "__cpp_designated_initializers != 201707" > +#endif > + > +#ifndef __cpp_constexpr_in_decltype > +# error "__cpp_constexpr_in_decltype" > +#elif __cpp_constexpr_in_decltype != 201711 > +# error "__cpp_constexpr_in_decltype != 201711" > +#endif > + > +#ifndef __cpp_consteval > +# error "__cpp_consteval" > +#elif __cpp_consteval != 202211L > +# error "__cpp_consteval != 202211L" > +#endif > + > +#ifndef __cpp_concepts > +# error "__cpp_concepts" > +#elif __cpp_concepts != 202002 > +# error "__cpp_concepts != 202002" > +#endif > + > +#ifndef __cpp_using_enum > +# error "__cpp_using_enum" > +#elif __cpp_using_enum != 201907 > +# error "__cpp_using_enum != 201907" > +#endif > + > +// C++20 attributes: > + > +#ifdef __has_cpp_attribute > + > +# if ! __has_cpp_attribute(maybe_unused) > +# error "__has_cpp_attribute(maybe_unused)" > +# elif __has_cpp_attribute(maybe_unused) != 201603 > +# error "__has_cpp_attribute(maybe_unused) != 201603" > +# endif > + > +# if ! __has_cpp_attribute(nodiscard) > +# error "__has_cpp_attribute(nodiscard)" > +# elif __has_cpp_attribute(nodiscard) != 201907 > +# error "__has_cpp_attribute(nodiscard) != 201907" > +# endif > + > +# if ! __has_cpp_attribute(fallthrough) > +# error "__has_cpp_attribute(fallthrough)" > +# elif __has_cpp_attribute(fallthrough) != 201603 > +# error "__has_cpp_attribute(fallthrough) != 201603" > +# endif > + > +# if ! __has_cpp_attribute(no_unique_address) > +# error "__has_cpp_attribute(no_unique_address)" > +# elif __has_cpp_attribute(no_unique_address) != 201803 > +# error "__has_cpp_attribute(no_unique_address) != 201803" > +# endif > + > +# if ! __has_cpp_attribute(likely) > +# error "__has_cpp_attribute(likely)" > +# elif __has_cpp_attribute(likely) != 201803 > +# error "__has_cpp_attribute(likely) != 201803" > +# endif > + > +# if ! __has_cpp_attribute(unlikely) > +# error "__has_cpp_attribute(unlikely)" > +# elif __has_cpp_attribute(unlikely) != 201803 > +# error "__has_cpp_attribute(unlikely) != 201803" > +# endif > + > +#else > +# error "__has_cpp_attribute" > +#endif > + > +// C++23 features: > + > +#ifndef __cpp_size_t_suffix > +# error "__cpp_size_t_suffix" > +#elif __cpp_size_t_suffix != 202011 > +# error "__cpp_size_t_suffix != 202011" > +#endif > + > +#ifndef __cpp_if_consteval > +# error "__cpp_if_consteval" > +#elif __cpp_if_consteval != 202106 > +# error "__cpp_if_consteval != 202106" > +#endif > + > +#ifndef __cpp_multidimensional_subscript > +# error "__cpp_multidimensional_subscript" > +#elif __cpp_multidimensional_subscript != 202211 > +# error "__cpp_multidimensional_subscript != 202211" > +#endif > + > +#ifndef __cpp_named_character_escapes > +# error "__cpp_named_character_escapes" > +#elif __cpp_named_character_escapes != 202207 > +# error "__cpp_named_character_escapes != 202207" > +#endif > + > +#ifndef __cpp_static_call_operator > +# error "__cpp_static_call_operator" > +#elif __cpp_static_call_operator != 202207 > +# error "__cpp_static_call_operator != 202207" > +#endif > + > +#ifndef __cpp_implicit_move > +# error "__cpp_implicit_move" > +#elif __cpp_implicit_move != 202207 > +# error "__cpp_implicit_move != 202207" > +#endif > + > +#ifndef __cpp_explicit_this_parameter > +# error "__cpp_explicit_this_parameter" > +#elif __cpp_explicit_this_parameter != 202110 > +# error "__cpp_explicit_this_parameter != 202110" > +#endif > + > +#ifndef __cpp_auto_cast > +# error "__cpp_auto_cast" > +#elif __cpp_auto_cast != 202110 > +# error "__cpp_auto_cast != 202110" > +#endif > + > +// C++23 attributes: > + > +#ifdef __has_cpp_attribute > +# if ! __has_cpp_attribute(assume) > +# error "__has_cpp_attribute(assume)" > +# elif __has_cpp_attribute(assume) != 202207 > +# error "__has_cpp_attribute(assume) != 202207" > +# endif > +#else > +# error "__has_cpp_attribute" > +#endif > + > +// C++26 features: > + > +#ifndef __cpp_placeholder_variables > +# error "__cpp_placeholder_variables" > +#elif __cpp_placeholder_variables != 202306 > +# error "__cpp_placeholder_variables != 202306" > +#endif > + > +#ifndef __cpp_deleted_function > +# error "__cpp_deleted_function" > +#elif __cpp_deleted_function != 202403 > +# error "__cpp_deleted_function != 202403" > +#endif > + > +#ifndef __cpp_variadic_friend > +# error "__cpp_variadic_friend" > +#elif __cpp_variadic_friend != 202403 > +# error "__cpp_variadic_friend != 202403" > +#endif > + > +#ifndef __cpp_pack_indexing > +# error "__cpp_pack_indexing" > +#elif __cpp_pack_indexing != 202311 > +# error "__cpp_pack_indexing != 202311" > +#endif > + > +#ifndef __cpp_pp_embed > +# error "__cpp_pp_embed" > +#elif __cpp_pp_embed != 202502 > +# error "__cpp_pp_embed != 202502" > +#endif > + > +#ifndef __cpp_constexpr_virtual_inheritance > +# error "__cpp_constexpr_virtual_inheritance" > +#elif __cpp_constexpr_virtual_inheritance != 202506 > +# error "__cpp_constexpr_virtual_inheritance != 202506" > +#endif > + > +#ifndef __cpp_constexpr_exceptions > +# error "__cpp_constexpr_exceptions" > +#elif __cpp_constexpr_exceptions != 202411 > +# error "__cpp_constexpr_exceptions != 202411" > +#endif > + > +#ifndef __cpp_expansion_statements > +# error "__cpp_expansion_statements" > +#elif __cpp_expansion_statements != 202506 > +# error "__cpp_expansion_statements != 202506" > +#endif > + > +#ifndef __cpp_trivial_union > +# error "__cpp_trivial_union" > +#elif __cpp_trivial_union != 202502 > +# error "__cpp_trivial_union != 202502" > +#endif > --- gcc/testsuite/lib/target-supports.exp.jj 2026-06-12 16:55:06.698171156 > +0200 > +++ gcc/testsuite/lib/target-supports.exp 2026-06-12 17:20:44.359659689 > +0200 > @@ -12540,7 +12540,35 @@ proc check_effective_target_c++26_only { > } > > proc check_effective_target_c++26 { } { > - return [check_effective_target_c++26_only] > + if [check_effective_target_c++26_only] { > + return 1 > + } > + return [check_effective_target_c++29] > +} > + > +proc check_effective_target_c++26_down { } { > + if ![check_effective_target_c++] { > + return 0 > + } > + return [expr ![check_effective_target_c++29] ] > +} > + > +proc check_effective_target_c++29_only { } { > + global cxx_default > + if ![check_effective_target_c++] { > + return 0 > + } > + if [check-flags { { } { } { -std=c++29 -std=gnu++29 -std=c++2d > -std=gnu++2d } }] { > + return 1 > + } > + if { $cxx_default == "c++29" && [check-flags { { } { } { } { -std=* } }] > } { > + return 1 > + } > + return 0 > +} > + > +proc check_effective_target_c++29 { } { > + return [check_effective_target_c++29_only] > } > > # Check for C++ Concepts support, i.e. -fconcepts flag. > --- gcc/testsuite/lib/g++-dg.exp.jj 2026-03-27 10:17:21.308213672 +0100 > +++ gcc/testsuite/lib/g++-dg.exp 2026-06-12 17:21:41.122906679 +0200 > @@ -78,7 +78,7 @@ proc g++-std-flags { test } { > # The order of this list is significant: first $cxx_default, > # then the oldest and newest, then others in rough order of > # importance based on test coverage and usage. > - foreach ver { 20 98 26 17 11 14 23 } { > + foreach ver { 20 98 26 17 11 14 23 29 } { > set cmpver $ver > if { $ver == 98 } { set cmpver 03 } > if { [llength $std_list] < 3 > --- gcc/dwarf2out.cc.jj 2026-05-30 17:45:09.404109533 +0200 > +++ gcc/dwarf2out.cc 2026-06-12 17:13:54.895111309 +0200 > @@ -25640,6 +25640,8 @@ static char *producer_string; > static const char * > highest_c_language (const char *lang1, const char *lang2) > { > + if (strcmp ("GNU C++29", lang1) == 0 || strcmp ("GNU C++29", lang2) == 0) > + return "GNU C++29"; > if (strcmp ("GNU C++26", lang1) == 0 || strcmp ("GNU C++26", lang2) == 0) > return "GNU C++26"; > if (strcmp ("GNU C++23", lang1) == 0 || strcmp ("GNU C++23", lang2) == 0) > @@ -25794,7 +25796,13 @@ gen_compile_unit_die (const char *filena > { > language = DW_LANG_C_plus_plus_14; > lname = DW_LNAME_C_plus_plus; > - lversion = 202400; > + lversion = 202603; > + } > + else if (strcmp (language_string, "GNU C++29") == 0) > + { > + language = DW_LANG_C_plus_plus_14; > + lname = DW_LNAME_C_plus_plus; > + lversion = 202700; > } > } > } > --- libcpp/include/cpplib.h.jj 2026-05-30 17:45:09.502108293 +0200 > +++ libcpp/include/cpplib.h 2026-06-12 17:22:11.101508989 +0200 > @@ -183,7 +183,8 @@ enum c_lang {CLK_GNUC89 = 0, CLK_GNUC99, > CLK_GNUCXX, CLK_CXX98, CLK_GNUCXX11, CLK_CXX11, > CLK_GNUCXX14, CLK_CXX14, CLK_GNUCXX17, CLK_CXX17, > CLK_GNUCXX20, CLK_CXX20, CLK_GNUCXX23, CLK_CXX23, > - CLK_GNUCXX26, CLK_CXX26, CLK_ASM}; > + CLK_GNUCXX26, CLK_CXX26, CLK_GNUCXX29, CLK_CXX29, > + CLK_ASM}; > > /* Payload of a NUMBER, STRING, CHAR or COMMENT token. */ > struct GTY(()) cpp_string { > --- libcpp/init.cc.jj 2026-03-27 10:17:21.566209462 +0100 > +++ libcpp/init.cc 2026-06-12 17:23:29.230472545 +0200 > @@ -151,6 +151,8 @@ static const struct lang_flags lang_defa > /* CXX23 */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0,0,1 }, > /* GNUCXX26 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,1,0,1 }, > /* CXX26 */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,1,0,1 }, > + /* GNUCXX29 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,1,0,1 }, > + /* CXX29 */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,1,0,1 }, > /* ASM */ { 0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 } > }; > > @@ -599,11 +601,14 @@ cpp_init_builtins (cpp_reader *pfile, in > > if (CPP_OPTION (pfile, cplusplus)) > { > - /* C++26 is not yet a standard. For now, use an invalid > - year/month, 202400L, which is larger than 202302L. */ > - if (CPP_OPTION (pfile, lang) == CLK_CXX26 > - || CPP_OPTION (pfile, lang) == CLK_GNUCXX26) > - _cpp_define_builtin (pfile, "__cplusplus 202400L"); > + /* C++29 is not yet a standard. For now, use an invalid > + year/month, 202700L, which is larger than 202603L. */ > + if (CPP_OPTION (pfile, lang) == CLK_CXX29 > + || CPP_OPTION (pfile, lang) == CLK_GNUCXX29) > + _cpp_define_builtin (pfile, "__cplusplus 202700L"); > + else if (CPP_OPTION (pfile, lang) == CLK_CXX26 > + || CPP_OPTION (pfile, lang) == CLK_GNUCXX26) > + _cpp_define_builtin (pfile, "__cplusplus 202603L"); > else if (CPP_OPTION (pfile, lang) == CLK_CXX23 > || CPP_OPTION (pfile, lang) == CLK_GNUCXX23) > _cpp_define_builtin (pfile, "__cplusplus 202302L"); > > Jakub > Marek
