1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <memory> 11 12 // weak_ptr 13 14 // void swap(weak_ptr& r); 15 16 #include <memory> 17 #include <cassert> 18 19 struct A 20 { 21 static int count; 22 AA23 A() {++count;} AA24 A(const A&) {++count;} ~AA25 ~A() {--count;} 26 }; 27 28 int A::count = 0; 29 main()30int main() 31 { 32 { 33 std::shared_ptr<A> p1(new A); 34 std::weak_ptr<A> w1(p1); 35 assert(w1.use_count() == 1); 36 w1.reset(); 37 assert(w1.use_count() == 0); 38 assert(p1.use_count() == 1); 39 } 40 assert(A::count == 0); 41 } 42