| 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 |
|---|
| 10 | // <optional> |
|---|
| 11 | |
|---|
| 12 | // constexpr T&& optional<T>::operator*() &&; |
|---|
| 13 | |
|---|
| 14 | #include <optional> |
|---|
| 15 | #include <type_traits> |
|---|
| 16 | #include <cassert> |
|---|
| 17 | |
|---|
| 18 | #include "test_macros.h" |
|---|
| 19 | |
|---|
| 20 | using std::optional; |
|---|
| 21 | |
|---|
| 22 | struct X |
|---|
| 23 | { |
|---|
| 24 | constexpr int test() const& {return 3;} |
|---|
| 25 | int test() & {return 4;} |
|---|
| 26 | constexpr int test() const&& {return 5;} |
|---|
| 27 | int test() && {return 6;} |
|---|
| 28 | }; |
|---|
| 29 | |
|---|
| 30 | struct Y |
|---|
| 31 | { |
|---|
| 32 | constexpr int test() && {return 7;} |
|---|
| 33 | }; |
|---|
| 34 | |
|---|
| 35 | constexpr int |
|---|
| 36 | test() |
|---|
| 37 | { |
|---|
| 38 | optional<Y> opt{Y{}}; |
|---|
| 39 | return (*std::move(opt)).test(); |
|---|
| 40 | } |
|---|
| 41 | |
|---|
| 42 | int main(int, char**) |
|---|
| 43 | { |
|---|
| 44 | { |
|---|
| 45 | optional<X> opt; ((void)opt); |
|---|
| 46 | ASSERT_SAME_TYPE(decltype(*std::move(opt)), X&&); |
|---|
| 47 | LIBCPP_STATIC_ASSERT(noexcept(*opt)); |
|---|
| 48 | // ASSERT_NOT_NOEXCEPT(*std::move(opt)); |
|---|
| 49 | // FIXME: This assertion fails with GCC because it can see that |
|---|
| 50 | // (A) operator*() is constexpr, and |
|---|
| 51 | // (B) there is no path through the function that throws. |
|---|
| 52 | // It's arguable if this is the correct behavior for the noexcept |
|---|
| 53 | // operator. |
|---|
| 54 | // Regardless this function should still be noexcept(false) because |
|---|
| 55 | // it has a narrow contract. |
|---|
| 56 | } |
|---|
| 57 | { |
|---|
| 58 | optional<X> opt(X{}); |
|---|
| 59 | assert((*std::move(opt)).test() == 6); |
|---|
| 60 | } |
|---|
| 61 | static_assert(test() == 7, "" ); |
|---|
| 62 | |
|---|
| 63 | return 0; |
|---|
| 64 | } |
|---|
| 65 | |
|---|
