181ad6265SDimitry Andric //===----------------------------------------------------------------------===// 281ad6265SDimitry Andric // 381ad6265SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 481ad6265SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 581ad6265SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 681ad6265SDimitry Andric // 781ad6265SDimitry Andric //===----------------------------------------------------------------------===// 881ad6265SDimitry Andric 981ad6265SDimitry Andric #ifndef _LIBCPP___TYPE_TRAITS_ADD_LVALUE_REFERENCE_H 1081ad6265SDimitry Andric #define _LIBCPP___TYPE_TRAITS_ADD_LVALUE_REFERENCE_H 1181ad6265SDimitry Andric 1281ad6265SDimitry Andric #include <__config> 1381ad6265SDimitry Andric #include <__type_traits/is_referenceable.h> 1481ad6265SDimitry Andric 1581ad6265SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 1681ad6265SDimitry Andric # pragma GCC system_header 1781ad6265SDimitry Andric #endif 1881ad6265SDimitry Andric 1981ad6265SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 2081ad6265SDimitry Andric 211f571f87SDimitry Andric #if __has_builtin(__add_lvalue_reference) 22bdd1243dSDimitry Andric 231f571f87SDimitry Andric template <class _Tp> 24bdd1243dSDimitry Andric using __add_lvalue_reference_t = __add_lvalue_reference(_Tp); 25bdd1243dSDimitry Andric 261f571f87SDimitry Andric #else 27bdd1243dSDimitry Andric 281f571f87SDimitry Andric template <class _Tp, bool = __libcpp_is_referenceable<_Tp>::value> 291f571f87SDimitry Andric struct __add_lvalue_reference_impl { 301f571f87SDimitry Andric typedef _LIBCPP_NODEBUG _Tp type; 311f571f87SDimitry Andric }; 32bdd1243dSDimitry Andric template <class _Tp > 33bdd1243dSDimitry Andric struct __add_lvalue_reference_impl<_Tp, true> { 34bdd1243dSDimitry Andric typedef _LIBCPP_NODEBUG _Tp& type; 35bdd1243dSDimitry Andric }; 3681ad6265SDimitry Andric 37bdd1243dSDimitry Andric template <class _Tp> 38bdd1243dSDimitry Andric using __add_lvalue_reference_t = typename __add_lvalue_reference_impl<_Tp>::type; 39bdd1243dSDimitry Andric 401f571f87SDimitry Andric #endif // __has_builtin(__add_lvalue_reference) 4181ad6265SDimitry Andric 42bdd1243dSDimitry Andric template <class _Tp> 43bdd1243dSDimitry Andric struct add_lvalue_reference { 44bdd1243dSDimitry Andric using type _LIBCPP_NODEBUG = __add_lvalue_reference_t<_Tp>; 45bdd1243dSDimitry Andric }; 46bdd1243dSDimitry Andric 4706c3fb27SDimitry Andric #if _LIBCPP_STD_VER >= 14 4806c3fb27SDimitry Andric template <class _Tp> 4906c3fb27SDimitry Andric using add_lvalue_reference_t = __add_lvalue_reference_t<_Tp>; 5081ad6265SDimitry Andric #endif 5181ad6265SDimitry Andric 5281ad6265SDimitry Andric _LIBCPP_END_NAMESPACE_STD 5381ad6265SDimitry Andric 5481ad6265SDimitry Andric #endif // _LIBCPP___TYPE_TRAITS_ADD_LVALUE_REFERENCE_H 55