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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <memory>
// weak_ptr
// shared_ptr<T> lock() const;
#include <memory>
#include <cassert>
struct A
{
static int count;
A() {++count;}
A(const A&) {++count;}
~A() {--count;}
};
int A::count = 0;
int main()
{
{
std::weak_ptr<A> wp;
std::shared_ptr<A> sp = wp.lock();
assert(sp.use_count() == 0);
assert(sp.get() == 0);
assert(A::count == 0);
}
{
std::shared_ptr<A> sp0(new A);
std::weak_ptr<A> wp(sp0);
std::shared_ptr<A> sp = wp.lock();
assert(sp.use_count() == 2);
assert(sp.get() == sp0.get());
assert(A::count == 1);
}
assert(A::count == 0);
{
std::shared_ptr<A> sp0(new A);
std::weak_ptr<A> wp(sp0);
sp0.reset();
std::shared_ptr<A> sp = wp.lock();
assert(sp.use_count() == 0);
assert(sp.get() == 0);
assert(A::count == 0);
}
assert(A::count == 0);
}
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