1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <utility> 11 12 // template <class T> typename add_rvalue_reference<T>::type declval() noexcept; 13 14 #include <utility> 15 #include <type_traits> 16 17 class A 18 { 19 A(const A&); 20 A& operator=(const A&); 21 }; 22 23 int main() 24 { 25 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 26 static_assert((std::is_same<decltype(std::declval<A>()), A&&>::value), ""); 27 #else 28 static_assert((std::is_same<decltype(std::declval<A>()), A>::value), ""); 29 #endif 30 } 31