1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14
// <optional>
// constexpr T&& optional<T>::operator*() const &&;
#include <optional>
#include <type_traits>
#include <cassert>
#include "test_macros.h"
using std::optional;
struct X
{
constexpr int test() const& {return 3;}
int test() & {return 4;}
constexpr int test() const&& {return 5;}
int test() && {return 6;}
};
struct Y
{
int test() const && {return 2;}
};
int main(int, char**)
{
{
const optional<X> opt; ((void)opt);
ASSERT_SAME_TYPE(decltype(*std::move(opt)), X const &&);
LIBCPP_STATIC_ASSERT(noexcept(*opt));
// ASSERT_NOT_NOEXCEPT(*std::move(opt));
// FIXME: This assertion fails with GCC because it can see that
// (A) operator*() is constexpr, and
// (B) there is no path through the function that throws.
// It's arguable if this is the correct behavior for the noexcept
// operator.
// Regardless this function should still be noexcept(false) because
// it has a narrow contract.
}
{
constexpr optional<X> opt(X{});
static_assert((*std::move(opt)).test() == 5, "");
}
{
constexpr optional<Y> opt(Y{});
assert((*std::move(opt)).test() == 2);
}
return 0;
}
|
