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/*
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
#include <iostream>
#include <memory>
#pragma clang diagnostic ignored "-Wdangling-gsl"
// just a struct
struct A {
int f;
~A() {}
};
// a function that returns an object, here a unique_ptr
std::unique_ptr<A> return_object() { return std::unique_ptr<A>(new A()); }
int main() {
// the compiler creates a C++ temporary to hold the result
// of the function call
const A& a_ref = *return_object();
// the lifetime of the temporary is only the expression
// above, so the pointer inside a_ref has been deleted
// by unique_ptr's destructor
std::cout << a_ref.f; // a_ref is garbage now; boom.
return 0;
}