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
13 // (possibly cv-qualified) in_place_t 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     using std::experimental::in_place_t;
22     using std::experimental::in_place;
23 
24     optional<const in_place_t> opt;
25 #else
26 #error
27 #endif  // _LIBCPP_STD_VER > 11
28 }
29