@@ -3602,6 +3602,12 @@ template<typename _Ret, typename _Fn, typename... _Args>
/// True if the type is a scoped enumeration type.
/// @since C++23
+# if _GLIBCXX_USE_BUILTIN_TRAIT(__is_scoped_enum)
+ template<typename _Tp>
+ struct is_scoped_enum
+ : bool_constant<__is_scoped_enum(_Tp)>
+ { };
+# else
template<typename _Tp>
struct is_scoped_enum
: false_type
@@ -3613,11 +3619,17 @@ template<typename _Ret, typename _Fn, typename... _Args>
struct is_scoped_enum<_Tp>
: bool_constant<!requires(_Tp __t, void(*__f)(int)) { __f(__t); }>
{ };
+# endif
/// @ingroup variable_templates
/// @since C++23
+# if _GLIBCXX_USE_BUILTIN_TRAIT(__is_scoped_enum)
+ template<typename _Tp>
+ inline constexpr bool is_scoped_enum_v = __is_scoped_enum(_Tp);
+# else
template<typename _Tp>
inline constexpr bool is_scoped_enum_v = is_scoped_enum<_Tp>::value;
+# endif
#endif
#ifdef __cpp_lib_reference_from_temporary // C++ >= 23 && ref_{converts,constructs}_from_temp
This patch optimizes the compilation performance of std::is_scoped_enum by dispatching to the new __is_scoped_enum built-in trait. libstdc++-v3/ChangeLog: * include/std/type_traits (is_scoped_enum): Use __is_scoped_enum built-in trait. (is_scoped_enum_v): Likewise. Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org> --- libstdc++-v3/include/std/type_traits | 12 ++++++++++++ 1 file changed, 12 insertions(+)