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 // shared_ptr 13 14 // template<class Y> explicit shared_ptr(const weak_ptr<Y>& r); 15 16 #include <memory> 17 #include <cassert> 18 19 struct B 20 { 21 static int count; 22 23 B() {++count;} 24 B(const B&) {++count;} 25 virtual ~B() {--count;} 26 }; 27 28 int B::count = 0; 29 30 struct A 31 : public B 32 { 33 static int count; 34 35 A() {++count;} 36 A(const A&) {++count;} 37 ~A() {--count;} 38 }; 39 40 int A::count = 0; 41 42 int main() 43 { 44 { 45 std::weak_ptr<A> wp; 46 try 47 { 48 std::shared_ptr<A> sp(wp); 49 assert(false); 50 } 51 catch (std::bad_weak_ptr&) 52 { 53 } 54 assert(A::count == 0); 55 } 56 { 57 std::shared_ptr<A> sp0(new A); 58 std::weak_ptr<A> wp(sp0); 59 std::shared_ptr<A> sp(wp); 60 assert(sp.use_count() == 2); 61 assert(sp.get() == sp0.get()); 62 assert(A::count == 1); 63 } 64 assert(A::count == 0); 65 { 66 std::shared_ptr<A> sp0(new A); 67 std::weak_ptr<A> wp(sp0); 68 sp0.reset(); 69 try 70 { 71 std::shared_ptr<A> sp(wp); 72 assert(false); 73 } 74 catch (std::bad_weak_ptr&) 75 { 76 } 77 } 78 assert(A::count == 0); 79 } 80
