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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 T, class U> shared_ptr<T> const_pointer_cast(const shared_ptr<U>& 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;
int main()
{
{
const std::shared_ptr<const A> pA(new A);
std::shared_ptr<A> pB = std::const_pointer_cast<A>(pA);
assert(pB.get() == pA.get());
assert(!pB.owner_before(pA) && !pA.owner_before(pB));
}
{
const std::shared_ptr<const A> pA;
std::shared_ptr<A> pB = std::const_pointer_cast<A>(pA);
assert(pB.get() == pA.get());
assert(!pB.owner_before(pA) && !pA.owner_before(pB));
}
}
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