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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>
// shared_ptr
// template<class Y> shared_ptr(const shared_ptr<Y>& r);
#include <memory>
#include <type_traits>
#include <cassert>
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&) {++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;
int main()
{
static_assert(( std::is_convertible<std::shared_ptr<A>, std::shared_ptr<B> >::value), "");
static_assert((!std::is_convertible<std::shared_ptr<B>, std::shared_ptr<A> >::value), "");
static_assert((!std::is_convertible<std::shared_ptr<A>, std::shared_ptr<C> >::value), "");
{
const std::shared_ptr<A> pA(new A);
assert(pA.use_count() == 1);
assert(B::count == 1);
assert(A::count == 1);
{
std::shared_ptr<B> pB(pA);
assert(B::count == 1);
assert(A::count == 1);
assert(pB.use_count() == 2);
assert(pA.use_count() == 2);
assert(pA.get() == pB.get());
}
assert(pA.use_count() == 1);
assert(B::count == 1);
assert(A::count == 1);
}
assert(B::count == 0);
assert(A::count == 0);
{
std::shared_ptr<A> pA;
assert(pA.use_count() == 0);
assert(B::count == 0);
assert(A::count == 0);
{
std::shared_ptr<B> pB(pA);
assert(B::count == 0);
assert(A::count == 0);
assert(pB.use_count() == 0);
assert(pA.use_count() == 0);
assert(pA.get() == pB.get());
}
assert(pA.use_count() == 0);
assert(B::count == 0);
assert(A::count == 0);
}
assert(B::count == 0);
assert(A::count == 0);
}
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