On Wed, Jul 19, 2023 at 3:33 PM Ken Matsui via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > This patch defines _GLIBCXX_HAS_BUILTIN_TRAIT macro, which will be used > as a flag to toggle the use of built-in traits in the type_traits header > through _GLIBCXX_NO_BUILTIN_TRAITS macro, without needing to modify the > source code.
LGTM! > > libstdc++-v3/ChangeLog: > > * include/bits/c++config (_GLIBCXX_HAS_BUILTIN_TRAIT): Define. > (_GLIBCXX_HAS_BUILTIN): Keep defined. > > Signed-off-by: Ken Matsui <kmat...@gcc.gnu.org> > --- > libstdc++-v3/include/bits/c++config | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/libstdc++-v3/include/bits/c++config > b/libstdc++-v3/include/bits/c++config > index dd47f274d5f..984985d6fff 100644 > --- a/libstdc++-v3/include/bits/c++config > +++ b/libstdc++-v3/include/bits/c++config > @@ -854,7 +854,15 @@ namespace __gnu_cxx > # define _GLIBCXX_HAVE_BUILTIN_LAUNDER 1 > #endif > > -#undef _GLIBCXX_HAS_BUILTIN > +// Returns 1 if _GLIBCXX_NO_BUILTIN_TRAITS is not defined and the compiler > +// has a corresponding built-in type trait, 0 otherwise. > +// _GLIBCXX_NO_BUILTIN_TRAITS can be defined to disable the use of built-in > +// traits. > +#ifndef _GLIBCXX_NO_BUILTIN_TRAITS > +# define _GLIBCXX_HAS_BUILTIN_TRAIT(BT) _GLIBCXX_HAS_BUILTIN(BT) > +#else > +# define _GLIBCXX_HAS_BUILTIN_TRAIT(BT) 0 > +#endif > > // Mark code that should be ignored by the compiler, but seen by Doxygen. > #define _GLIBCXX_DOXYGEN_ONLY(X) > -- > 2.41.0 >
