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
main()18 int main()
19 {
20 using std::experimental::optional;
21
22 optional<int&> opt;
23 }
24