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 // UNSUPPORTED: c++98, c++03, c++11 11 // <optional> 12 13 // A program that necessitates the instantiation of template optional for a 14 // reference type is ill-formed. 15 16 #include <experimental/optional> 17 18 int main() 19 { 20 using std::experimental::optional; 21 22 optional<const int&> opt; 23 } 24
