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.
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