Perma-workaround DevCom-1328628 "SFINAE bug when a default argument i…

…s protected".
microsoft · Feb 3, 2021 · 075dfaf · 075dfaf
1 parent 5bb20e5
commit 075dfaf
Showing 1 changed file with 4 additions and 4 deletions.
diff --git a/stl/inc/xutility b/stl/inc/xutility
@@ -131,10 +131,10 @@ _NODISCARD constexpr void* _Voidify_iter(_Iter _It) noexcept {
 
 // FUNCTION TEMPLATE construct_at
 #if _HAS_CXX20
-template <class _Ty, class... _Types>
-_CONSTEXPR20_DYNALLOC auto construct_at(_Ty* const _Location, _Types&&... _Args) noexcept(
-    noexcept(::new (_Voidify_iter(_Location)) _Ty(_STD forward<_Types>(_Args)...))) // strengthened
-    -> decltype(::new (_Voidify_iter(_Location)) _Ty(_STD forward<_Types>(_Args)...)) {
+template <class _Ty, class... _Types,
+    class = void_t<decltype(::new (_STD declval<void*>()) _Ty(_STD declval<_Types>()...))>>
+_CONSTEXPR20_DYNALLOC _Ty* construct_at(_Ty* const _Location, _Types&&... _Args) noexcept(
+    noexcept(::new (_Voidify_iter(_Location)) _Ty(_STD forward<_Types>(_Args)...))) /* strengthened */ {
     return ::new (_Voidify_iter(_Location)) _Ty(_STD forward<_Types>(_Args)...);
 }
 #endif // _HAS_CXX20