@@ -200,7 +200,7 @@
#endif
#define __cpp_lib_span 202002L
#if __cpp_impl_three_way_comparison >= 201907L && __cpp_lib_concepts
-# define __cpp_lib_three_way_comparison 201711L
+# define __cpp_lib_three_way_comparison 201907L
#endif
#define __cpp_lib_to_array 201907L
#endif
@@ -39,7 +39,7 @@
#include <concepts>
#if __cpp_lib_concepts
-# define __cpp_lib_three_way_comparison 201711L
+# define __cpp_lib_three_way_comparison 201907L
#endif
namespace std
@@ -866,12 +866,23 @@ namespace std
namespace __detail
{
- // [expos.only.func]
+ // [expos.only.func] synth-three-way
inline constexpr struct _Synth3way
{
+ template<typename _Tp, typename _Up>
+ static constexpr bool
+ _S_noexcept(const _Tp* __t = nullptr, const _Up* __u = nullptr)
+ {
+ if constexpr (three_way_comparable_with<_Tp, _Up>)
+ return noexcept(*__t <=> *__u);
+ else
+ return noexcept(*__t < *__u) && noexcept(*__u < *__t);
+ }
+
template<typename _Tp, typename _Up>
constexpr auto
operator()(const _Tp& __t, const _Up& __u) const
+ noexcept(_S_noexcept<_Tp, _Up>())
requires requires
{
{ __t < __u } -> __boolean_testable;
@@ -892,6 +903,7 @@ namespace std
}
} __synth3way = {};
+ // [expos.only.func] synth-three-way-result
template<typename _Tp, typename _Up = _Tp>
using __synth3way_t
= decltype(__detail::__synth3way(std::declval<_Tp&>(),