diff --git a/libcxx/include/__concepts/boolean_testable.h b/libcxx/include/__concepts/boolean_testable.h --- a/libcxx/include/__concepts/boolean_testable.h +++ b/libcxx/include/__concepts/boolean_testable.h @@ -11,6 +11,7 @@ #include <__concepts/convertible_to.h> #include <__config> +#include <__utility/forward.h> #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) #pragma GCC system_header @@ -27,7 +28,7 @@ template concept __boolean_testable = __boolean_testable_impl<_Tp> && requires(_Tp&& __t) { - { !static_cast<_Tp&&>(__t) } -> __boolean_testable_impl; + { !_VSTD::forward<_Tp>(__t) } -> __boolean_testable_impl; }; #endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CONCEPTS)