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// test forward
11
12#include <utility>
13#include <cassert>
14
15#include "test_macros.h"
16
17struct A
18{
19};
20
21A source() {return A();}
22const A csource() {return A();}
23
24typedef char one;
25struct two {one _[2];};
26struct four {one _[4];};
27struct eight {one _[8];};
28
29one test(A&);
30two test(const A&);
31
32int main()
33{
34    A a;
35    const A ca = A();
36
37    ((void)a); // Prevent unused warning
38    ((void)ca); // Prevent unused warning
39
40#if TEST_STD_VER < 11
41    static_assert(sizeof(test(std::forward<A&>(a))) == 1, "");
42    static_assert(sizeof(test(std::forward<A>(a))) == 1, "");
43
44    // Libc++'s C++03 implementation of 'forward' cannot accept true non-const
45    // rvalues.
46    // static_assert(sizeof(test(std::forward<A>(source()))) == 2, "");
47
48    static_assert(sizeof(test(std::forward<const A&>(a))) == 2, "");
49    static_assert(sizeof(test(std::forward<const A&>(source()))) == 2, "");
50    static_assert(sizeof(test(std::forward<const A>(a))) == 2, "");
51    static_assert(sizeof(test(std::forward<const A>(source()))) == 2, "");
52
53    static_assert(sizeof(test(std::forward<const A&>(ca))) == 2, "");
54    static_assert(sizeof(test(std::forward<const A&>(csource()))) == 2, "");
55    static_assert(sizeof(test(std::forward<const A>(ca))) == 2, "");
56    static_assert(sizeof(test(std::forward<const A>(csource()))) == 2, "");
57#endif
58}
59