This patch gets std::is_function to dispatch to new built-in trait __is_function.
libstdc++-v3/ChangeLog: * include/std/type_traits (is_function): Use __is_function built-in trait. (is_function_v): Likewise. Signed-off-by: Ken Matsui <kmat...@cs.washington.edu> --- libstdc++-v3/include/std/type_traits | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index 2a14df7e5f9..954b57518de 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -594,6 +594,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { }; /// is_function +#if __has_builtin(__is_function) + template<typename _Tp> + struct is_function + : public __bool_constant<__is_function(_Tp)> + { }; +#else template<typename _Tp> struct is_function : public __bool_constant<!is_const<const _Tp>::value> { }; @@ -605,6 +611,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template<typename _Tp> struct is_function<_Tp&&> : public false_type { }; +#endif #define __cpp_lib_is_null_pointer 201309L @@ -3197,8 +3204,14 @@ template <typename _Tp> inline constexpr bool is_union_v = __is_union(_Tp); template <typename _Tp> inline constexpr bool is_class_v = __is_class(_Tp); + +#if __has_builtin(__is_function) +template <typename _Tp> + inline constexpr bool is_function_v = __is_function(_Tp); +#else template <typename _Tp> inline constexpr bool is_function_v = is_function<_Tp>::value; +#endif #if __has_builtin(__is_reference) template <typename _Tp> -- 2.41.0