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, c++14
11 // <optional>
12 
13 // struct nullopt_t{see below};
14 
15 #include <optional>
16 
17 using std::optional;
18 using std::nullopt_t;
19 
main()20 int main()
21 {
22     // I roughly interpret LWG2736 as "it shall not be possible to copy-list-initialize nullopt_t with an
23     // empty braced-init-list."
24     nullopt_t foo = {};
25 }
26