| 1 | //===----------------------------------------------------------------------===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | |
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| 9 | // UNSUPPORTED: c++03, c++11, c++14 |
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| 10 | // <optional> |
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| 11 | |
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| 12 | // constexpr const T* optional<T>::operator->() const; |
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| 13 | |
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| 14 | #include <optional> |
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| 15 | #include <type_traits> |
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| 16 | #include <cassert> |
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| 17 | |
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| 18 | #include "test_macros.h" |
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| 19 | |
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| 20 | using std::optional; |
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| 21 | |
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| 22 | struct X |
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| 23 | { |
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| 24 | constexpr int test() const {return 3;} |
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| 25 | }; |
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| 26 | |
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| 27 | struct Y |
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| 28 | { |
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| 29 | int test() const noexcept {return 2;} |
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| 30 | }; |
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| 31 | |
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| 32 | struct Z |
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| 33 | { |
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| 34 | const Z* operator&() const; |
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| 35 | constexpr int test() const {return 1;} |
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| 36 | }; |
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| 37 | |
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| 38 | int main(int, char**) |
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| 39 | { |
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| 40 | { |
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| 41 | const std::optional<X> opt; ((void)opt); |
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| 42 | ASSERT_SAME_TYPE(decltype(opt.operator->()), X const*); |
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| 43 | // ASSERT_NOT_NOEXCEPT(opt.operator->()); |
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| 44 | // FIXME: This assertion fails with GCC because it can see that |
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| 45 | // (A) operator->() is constexpr, and |
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| 46 | // (B) there is no path through the function that throws. |
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| 47 | // It's arguable if this is the correct behavior for the noexcept |
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| 48 | // operator. |
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| 49 | // Regardless this function should still be noexcept(false) because |
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| 50 | // it has a narrow contract. |
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| 51 | } |
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| 52 | { |
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| 53 | constexpr optional<X> opt(X{}); |
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| 54 | static_assert(opt->test() == 3, "" ); |
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| 55 | } |
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| 56 | { |
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| 57 | constexpr optional<Y> opt(Y{}); |
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| 58 | assert(opt->test() == 2); |
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| 59 | } |
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| 60 | { |
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| 61 | constexpr optional<Z> opt(Z{}); |
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| 62 | static_assert(opt->test() == 1, "" ); |
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| 63 | } |
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| 64 | |
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| 65 | return 0; |
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| 66 | } |
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| 67 | |
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