 b64f8b07c1
			
		
	
	b64f8b07c1
	
	
	
		
			
			git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@119395 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			94 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			94 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| //===----------------------------------------------------------------------===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is dual licensed under the MIT and the University of Illinois Open
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| // Source Licenses. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| // <memory>
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| 
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| // weak_ptr
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| 
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| // weak_ptr(const weak_ptr& r);
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| 
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| #include <memory>
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| #include <type_traits>
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| #include <cassert>
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| 
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| struct B
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| {
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|     static int count;
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| 
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|     B() {++count;}
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|     B(const B&) {++count;}
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|     virtual ~B() {--count;}
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| };
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| 
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| int B::count = 0;
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| 
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| struct A
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|     : public B
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| {
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|     static int count;
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| 
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|     A() {++count;}
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|     A(const A&) {++count;}
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|     ~A() {--count;}
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| };
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| 
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| int A::count = 0;
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| 
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| struct C
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| {
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|     static int count;
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| 
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|     C() {++count;}
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|     C(const C&) {++count;}
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|     virtual ~C() {--count;}
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| };
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| 
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| int C::count = 0;
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| 
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| int main()
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| {
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|     {
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|         const std::shared_ptr<A> ps(new A);
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|         const std::weak_ptr<A> pA(ps);
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|         assert(pA.use_count() == 1);
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|         assert(B::count == 1);
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|         assert(A::count == 1);
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|         {
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|             std::weak_ptr<A> pB(pA);
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|             assert(B::count == 1);
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|             assert(A::count == 1);
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|             assert(pB.use_count() == 1);
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|             assert(pA.use_count() == 1);
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|         }
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|         assert(pA.use_count() == 1);
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|         assert(B::count == 1);
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|         assert(A::count == 1);
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|     }
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|     assert(B::count == 0);
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|     assert(A::count == 0);
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|     {
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|         std::weak_ptr<A> pA;
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|         assert(pA.use_count() == 0);
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|         assert(B::count == 0);
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|         assert(A::count == 0);
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|         {
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|             std::weak_ptr<A> pB(pA);
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|             assert(B::count == 0);
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|             assert(A::count == 0);
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|             assert(pB.use_count() == 0);
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|             assert(pA.use_count() == 0);
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|         }
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|         assert(pA.use_count() == 0);
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|         assert(B::count == 0);
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|         assert(A::count == 0);
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|     }
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|     assert(B::count == 0);
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|     assert(A::count == 0);
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| }
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