1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___TYPE_TRAITS_REFERENCE_CONSTRUCTS_FROM_TEMPORARY_H 10 #define _LIBCPP___TYPE_TRAITS_REFERENCE_CONSTRUCTS_FROM_TEMPORARY_H 11 12 #include <__config> 13 #include <__type_traits/integral_constant.h> 14 15 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 16 # pragma GCC system_header 17 #endif 18 19 _LIBCPP_BEGIN_NAMESPACE_STD 20 21 #if _LIBCPP_STD_VER >= 23 && __has_builtin(__reference_constructs_from_temporary) 22 23 template <class _Tp, class _Up> 24 struct _LIBCPP_NO_SPECIALIZATIONS reference_constructs_from_temporary 25 : public bool_constant<__reference_constructs_from_temporary(_Tp, _Up)> {}; 26 27 template <class _Tp, class _Up> 28 _LIBCPP_NO_SPECIALIZATIONS inline constexpr bool reference_constructs_from_temporary_v = 29 __reference_constructs_from_temporary(_Tp, _Up); 30 31 #endif 32 33 #if __has_builtin(__reference_constructs_from_temporary) 34 template <class _Tp, class _Up> 35 inline const bool __reference_constructs_from_temporary_v = __reference_constructs_from_temporary(_Tp, _Up); 36 #else 37 // TODO(LLVM 22): Remove this as all supported compilers should have __reference_constructs_from_temporary implemented. 38 template <class _Tp, class _Up> 39 inline const bool __reference_constructs_from_temporary_v = __reference_binds_to_temporary(_Tp, _Up); 40 #endif 41 42 _LIBCPP_END_NAMESPACE_STD 43 44 #endif // _LIBCPP___TYPE_TRAITS_REFERENCE_CONSTRUCTS_FROM_TEMPORARY_H 45