This patch lets libstdc++ use new built-in trait __is_pointer. libstdc++-v3/ChangeLog:
* include/bits/cpp_type_traits.h (__is_ptr): Use __is_pointer built-in trait. * include/std/type_traits (is_pointer): Likewise. (is_pointer_v): Likewise. Optimize its implementation. Signed-off-by: Ken Matsui <kmat...@gcc.gnu.org> --- libstdc++-v3/include/bits/cpp_type_traits.h | 8 +++++++ libstdc++-v3/include/std/type_traits | 25 +++++++++++++++++++-- 2 files changed, 31 insertions(+), 2 deletions(-) diff --git a/libstdc++-v3/include/bits/cpp_type_traits.h b/libstdc++-v3/include/bits/cpp_type_traits.h index 3711e4be526..4da1e7c407c 100644 --- a/libstdc++-v3/include/bits/cpp_type_traits.h +++ b/libstdc++-v3/include/bits/cpp_type_traits.h @@ -363,6 +363,13 @@ __INT_N(__GLIBCXX_TYPE_INT_N_3) // // Pointer types // +#if __has_builtin(__is_pointer) + template<typename _Tp> + struct __is_ptr : __truth_type<__is_pointer(_Tp)> + { + enum { __value = __is_pointer(_Tp) }; + }; +#else template<typename _Tp> struct __is_ptr { @@ -376,6 +383,7 @@ __INT_N(__GLIBCXX_TYPE_INT_N_3) enum { __value = 1 }; typedef __true_type __type; }; +#endif // // An arithmetic type is an integer type or a floating point type diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index 0e7a9c9c7f3..181a50e48d0 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -515,6 +515,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION struct is_array<_Tp[]> : public true_type { }; + /// is_pointer +#if __has_builtin(__is_pointer) + template<typename _Tp> + struct is_pointer + : public __bool_constant<__is_pointer(_Tp)> + { }; +#else template<typename> struct __is_pointer_helper : public false_type { }; @@ -523,11 +530,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION struct __is_pointer_helper<_Tp*> : public true_type { }; - /// is_pointer template<typename _Tp> struct is_pointer : public __is_pointer_helper<__remove_cv_t<_Tp>>::type { }; +#endif /// is_lvalue_reference template<typename> @@ -3168,8 +3175,22 @@ template <typename _Tp> template <typename _Tp, size_t _Num> inline constexpr bool is_array_v<_Tp[_Num]> = true; +#if __has_builtin(__is_pointer) template <typename _Tp> - inline constexpr bool is_pointer_v = is_pointer<_Tp>::value; + inline constexpr bool is_pointer_v = __is_pointer(_Tp); +#else +template <typename _Tp> + inline constexpr bool is_pointer_v = false; +template <typename _Tp> + inline constexpr bool is_pointer_v<_Tp*> = true; +template <typename _Tp> + inline constexpr bool is_pointer_v<_Tp* const> = true; +template <typename _Tp> + inline constexpr bool is_pointer_v<_Tp* volatile> = true; +template <typename _Tp> + inline constexpr bool is_pointer_v<_Tp* const volatile> = true; +#endif + template <typename _Tp> inline constexpr bool is_lvalue_reference_v = false; template <typename _Tp> -- 2.41.0