optional_lvalue_ref.fail.cpp revision 01afa5c6e407e985d9643707d7b7ab1384bd9317
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// <optional> 11 12// A program that necessitates the instantiation of template optional for a 13// reference type is ill-formed. 14 15#include <optional> 16 17int main() 18{ 19#if _LIBCPP_STD_VER > 11 20 std::optional<int&> opt; 21#else 22#error 23#endif // _LIBCPP_STD_VER > 11 24} 25