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 // shared_ptr& operator=(const shared_ptr& r); 15 16 #include <memory> 17 #include <type_traits> 18 #include <cassert> 19 20 struct B 21 { 22 static int count; 23 24 B() {++count;} 25 B(const B&) {++count;} 26 virtual ~B() {--count;} 27 }; 28 29 int B::count = 0; 30 31 struct A 32 : public B 33 { 34 static int count; 35 36 A() {++count;} 37 A(const A&) {++count;} 38 ~A() {--count;} 39 }; 40 41 int A::count = 0; 42 43 int main() 44 { 45 { 46 const std::shared_ptr<A> pA(new A); 47 A* ptrA = pA.get(); 48 { 49 std::shared_ptr<A> pB(new A); 50 pB = pA; 51 assert(B::count == 1); 52 assert(A::count == 1); 53 assert(pB.use_count() == 2); 54 assert(pA.use_count() == 2); 55 assert(pA.get() == pB.get()); 56 assert(pB.get() == ptrA); 57 } 58 assert(pA.use_count() == 1); 59 assert(B::count == 1); 60 assert(A::count == 1); 61 } 62 assert(B::count == 0); 63 assert(A::count == 0); 64 { 65 const std::shared_ptr<A> pA; 66 A* ptrA = pA.get(); 67 { 68 std::shared_ptr<A> pB(new A); 69 pB = pA; 70 assert(B::count == 0); 71 assert(A::count == 0); 72 assert(pB.use_count() == 0); 73 assert(pA.use_count() == 0); 74 assert(pA.get() == pB.get()); 75 assert(pB.get() == ptrA); 76 } 77 assert(pA.use_count() == 0); 78 assert(B::count == 0); 79 assert(A::count == 0); 80 } 81 assert(B::count == 0); 82 assert(A::count == 0); 83 { 84 const std::shared_ptr<A> pA(new A); 85 A* ptrA = pA.get(); 86 { 87 std::shared_ptr<A> pB; 88 pB = pA; 89 assert(B::count == 1); 90 assert(A::count == 1); 91 assert(pB.use_count() == 2); 92 assert(pA.use_count() == 2); 93 assert(pA.get() == pB.get()); 94 assert(pB.get() == ptrA); 95 } 96 assert(pA.use_count() == 1); 97 assert(B::count == 1); 98 assert(A::count == 1); 99 } 100 assert(B::count == 0); 101 assert(A::count == 0); 102 { 103 const std::shared_ptr<A> pA; 104 A* ptrA = pA.get(); 105 { 106 std::shared_ptr<A> pB; 107 pB = pA; 108 assert(B::count == 0); 109 assert(A::count == 0); 110 assert(pB.use_count() == 0); 111 assert(pA.use_count() == 0); 112 assert(pA.get() == pB.get()); 113 assert(pB.get() == ptrA); 114 } 115 assert(pA.use_count() == 0); 116 assert(B::count == 0); 117 assert(A::count == 0); 118 } 119 assert(B::count == 0); 120 assert(A::count == 0); 121 } 122
