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++98, c++03, c++11, c++14
10 
11 // <optional>
12 
13 // void reset() noexcept;
14 
15 #include <optional>
16 #include <type_traits>
17 #include <cassert>
18 
19 using std::optional;
20 
21 struct X
22 {
23     static bool dtor_called;
24     ~X() {dtor_called = true;}
25 };
26 
27 bool X::dtor_called = false;
28 
29 int main(int, char**)
30 {
31     {
32         optional<int> opt;
33         static_assert(noexcept(opt.reset()) == true, "");
34         opt.reset();
35         assert(static_cast<bool>(opt) == false);
36     }
37     {
38         optional<int> opt(3);
39         opt.reset();
40         assert(static_cast<bool>(opt) == false);
41     }
42     {
43         optional<X> opt;
44         static_assert(noexcept(opt.reset()) == true, "");
45         assert(X::dtor_called == false);
46         opt.reset();
47         assert(X::dtor_called == false);
48         assert(static_cast<bool>(opt) == false);
49     }
50     {
51         optional<X> opt(X{});
52         X::dtor_called = false;
53         opt.reset();
54         assert(X::dtor_called == true);
55         assert(static_cast<bool>(opt) == false);
56         X::dtor_called = false;
57     }
58 
59   return 0;
60 }
61