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37 lines
902 B
37 lines
902 B
6 years ago
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/*
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* Copyright (c) 2018-present, Facebook, Inc.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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#include <iostream>
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namespace temporaries {
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struct A {
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int f;
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};
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std::unique_ptr<A> some_f();
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void FN_call_some_f_deref_bad() {
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const A& a_ref = *some_f(); // temporary unique_ptr returned by `some_f` is
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// destroyed at the end of the statement
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std::cout << a_ref.f;
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}
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void call_some_f_ok() {
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auto local = some_f(); // ok, as ownership of a temporary unique_ptr is passed
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// to `local`
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const A& a_ref = *local;
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std::cout << a_ref.f;
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}
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void call_some_f_copy_object_ok() {
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auto a = *some_f().get(); // ok, as value is copied before temporary
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// unique_prt is destroyed
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std::cout << a.f;
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}
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} // namespace temporaries
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