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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// <memory>
// weak_ptr
// weak_ptr(const weak_ptr& r);
// weak_ptr(weak_ptr &&r)
#include <memory>
#include <type_traits>
#include <cassert>
#include <utility>
#include "test_macros.h"
struct B
{
static int count;
B() {++count;}
B(const B&) {++count;}
virtual ~B() {--count;}
};
int B::count = 0;
struct A
: public B
{
static int count;
A() {++count;}
A(const A& other) : B(other) {++count;}
~A() {--count;}
};
int A::count = 0;
struct C
{
static int count;
C() {++count;}
C(const C&) {++count;}
virtual ~C() {--count;}
};
int C::count = 0;
template <class T>
std::weak_ptr<T> source (std::shared_ptr<T> p) { return std::weak_ptr<T>(p); }
#if TEST_STD_VER >= 11
template <class T>
void sink (std::weak_ptr<T> &&) {}
#endif
int main(int, char**)
{
{
const std::shared_ptr<A> ps(new A);
const std::weak_ptr<A> pA(ps);
assert(pA.use_count() == 1);
assert(B::count == 1);
assert(A::count == 1);
{
std::weak_ptr<A> pB(pA);
assert(B::count == 1);
assert(A::count == 1);
assert(pB.use_count() == 1);
assert(pA.use_count() == 1);
}
assert(pA.use_count() == 1);
assert(B::count == 1);
assert(A::count == 1);
}
assert(B::count == 0);
assert(A::count == 0);
{
std::weak_ptr<A> pA;
assert(pA.use_count() == 0);
assert(B::count == 0);
assert(A::count == 0);
{
std::weak_ptr<A> pB(pA);
assert(B::count == 0);
assert(A::count == 0);
assert(pB.use_count() == 0);
assert(pA.use_count() == 0);
}
assert(pA.use_count() == 0);
assert(B::count == 0);
assert(A::count == 0);
}
assert(B::count == 0);
assert(A::count == 0);
#if TEST_STD_VER >= 11
{
std::shared_ptr<A> ps(new A);
std::weak_ptr<A> pA = source(ps);
assert(pA.use_count() == 1);
assert(A::count == 1);
sink(std::move(pA)); // kill off the weak pointer
}
assert(B::count == 0);
assert(A::count == 0);
#endif
return 0;
}
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