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 <experimental/optional>
16
main()17 int main()
18 {
19 #if _LIBCPP_STD_VER > 11
20 using std::experimental::optional;
21
22 optional<int&&> opt;
23 #else
24 #error
25 #endif // _LIBCPP_STD_VER > 11
26 }
27