This patch uses _GLIBCXX_USE_BUILTIN_TRAIT macro instead of __has_builtin in the type_traits header for traits that have a corresponding fallback non-built-in implementation. This macro supports to toggle the use of built-in traits in the type_traits header through _GLIBCXX_DO_NOT_USE_BUILTIN_TRAITS macro, without needing to modify the source code.
libstdc++-v3/ChangeLog: * include/std/type_traits: Use _GLIBCXX_USE_BUILTIN_TRAIT. Signed-off-by: Ken Matsui <kmat...@gcc.gnu.org> Reviewed-by: Patrick Palka <ppa...@redhat.com> --- libstdc++-v3/include/std/type_traits | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index f00c07f94f9..ba35ffb27fa 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -1481,7 +1481,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION : public __bool_constant<__is_base_of(_Base, _Derived)> { }; -#if __has_builtin(__is_convertible) +#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_convertible) template<typename _From, typename _To> struct is_convertible : public __bool_constant<__is_convertible(_From, _To)> @@ -1531,7 +1531,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION #ifdef __cpp_lib_is_nothrow_convertible // C++ >= 20 -#if __has_builtin(__is_nothrow_convertible) +#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_nothrow_convertible) /// is_nothrow_convertible_v template<typename _From, typename _To> inline constexpr bool is_nothrow_convertible_v @@ -1606,7 +1606,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { using type = _Tp; }; /// remove_cv -#if __has_builtin(__remove_cv) +#if _GLIBCXX_USE_BUILTIN_TRAIT(__remove_cv) template<typename _Tp> struct remove_cv { using type = __remove_cv(_Tp); }; @@ -1672,7 +1672,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // Reference transformations. /// remove_reference -#if __has_builtin(__remove_reference) +#if _GLIBCXX_USE_BUILTIN_TRAIT(__remove_reference) template<typename _Tp> struct remove_reference { using type = __remove_reference(_Tp); }; @@ -3537,7 +3537,7 @@ template<typename _Ret, typename _Fn, typename... _Args> * @{ */ #ifdef __cpp_lib_remove_cvref // C++ >= 20 -# if __has_builtin(__remove_cvref) +# if _GLIBCXX_USE_BUILTIN_TRAIT(__remove_cvref) template<typename _Tp> struct remove_cvref { using type = __remove_cvref(_Tp); }; -- 2.43.0