1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: c++03, c++11, c++14, c++17
10 
11 // <functional>
12 //
13 // reference_wrapper<T>
14 //
15 //  where T is an incomplete type (since C++20)
16 
17 
18 #include <functional>
19 #include <cassert>
20 
21 #include "test_macros.h"
22 
23 
24 struct Foo;
25 
26 Foo& get_foo();
27 
test()28 void test() {
29     Foo& foo = get_foo();
30     std::reference_wrapper<Foo> ref{foo};
31     assert(&ref.get() == &foo);
32 }
33 
34 struct Foo { };
35 
get_foo()36 Foo& get_foo() {
37     static Foo foo;
38     return foo;
39 }
40 
main()41 int main() {
42     test();
43 }
44