74 lines
1.8 KiB
C++
74 lines
1.8 KiB
C++
//===----------------------------------------------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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// UNSUPPORTED: c++98, c++03, c++11, c++14
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// <optional>
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// constexpr T&& optional<T>::operator*() &&;
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#ifdef _LIBCPP_DEBUG
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#define _LIBCPP_ASSERT(x, m) ((x) ? (void)0 : std::exit(0))
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#endif
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#include <optional>
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#include <type_traits>
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#include <cassert>
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#include "test_macros.h"
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using std::optional;
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struct X
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{
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constexpr int test() const& {return 3;}
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int test() & {return 4;}
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constexpr int test() const&& {return 5;}
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int test() && {return 6;}
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};
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struct Y
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{
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constexpr int test() && {return 7;}
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};
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constexpr int
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test()
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{
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optional<Y> opt{Y{}};
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return (*std::move(opt)).test();
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}
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int main()
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{
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{
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optional<X> opt; ((void)opt);
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ASSERT_SAME_TYPE(decltype(*std::move(opt)), X&&);
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// ASSERT_NOT_NOEXCEPT(*std::move(opt));
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// FIXME: This assertion fails with GCC because it can see that
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// (A) operator*() is constexpr, and
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// (B) there is no path through the function that throws.
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// It's arguable if this is the correct behavior for the noexcept
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// operator.
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// Regardless this function should still be noexcept(false) because
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// it has a narrow contract.
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}
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{
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optional<X> opt(X{});
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assert((*std::move(opt)).test() == 6);
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}
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static_assert(test() == 7, "");
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#ifdef _LIBCPP_DEBUG
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{
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optional<X> opt;
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assert((*std::move(opt)).test() == 3);
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assert(false);
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}
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#endif // _LIBCPP_DEBUG
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}
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