forked from OSchip/llvm-project
48 lines
1.6 KiB
C++
48 lines
1.6 KiB
C++
//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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// <optional>
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// UNSUPPORTED: c++98, c++03, c++11, c++14
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// UNSUPPORTED: clang-5
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// UNSUPPORTED: libcpp-no-deduction-guides
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// Clang 5 will generate bad implicit deduction guides
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// Specifically, for the copy constructor.
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// template<class T>
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// optional(T) -> optional<T>;
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#include <optional>
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#include <cassert>
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struct A {};
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int main(int, char**)
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{
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// Test the explicit deduction guides
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// Test the implicit deduction guides
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{
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// optional()
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std::optional opt; // expected-error-re {{{{declaration of variable 'opt' with deduced type 'std::optional' requires an initializer|no viable constructor or deduction guide for deduction of template arguments of 'optional'}}}}
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// clang-6 gives a bogus error here:
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// declaration of variable 'opt' with deduced type 'std::optional' requires an initializer
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// clang-7 (and later) give a better message:
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// no viable constructor or deduction guide for deduction of template arguments of 'optional'
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// So we check for one or the other.
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}
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{
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// optional(nullopt_t)
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std::optional opt(std::nullopt); // expected-error-re@optional:* {{static_assert failed{{.*}} "instantiation of optional with nullopt_t is ill-formed"}}
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}
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return 0;
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}
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