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    <p>Okay, we understood that behavior is not defined. But let's do small journey into what really happends. I use VS 2008. </p> <p>Here is my code:</p> <pre><code>class Test { int i; public: Test() : i(3) { } ~Test() { if (!i) return; printf("%d", i); i--; Test::~Test(); } }; int _tmain(int argc, _TCHAR* argv[]) { delete new Test(); return 0; } </code></pre> <p>Let's run it and set a breakpoint inside destructor and let the miracle of recursion happen. </p> <p>Here is stack trace:</p> <p><a href="http://img638.imageshack.us/img638/8508/dest.png" rel="nofollow noreferrer">alt text http://img638.imageshack.us/img638/8508/dest.png</a></p> <p>What is that <code>scalar deleting destructor</code>? It is something that compiler inserts between delete and our actual code. Destructor itself is just a method, there is nothing special about it. It doesn't really release the memory. It is released somewhere inside that <code>scalar deleting destructor</code>. </p> <p>Let's go to <code>scalar deleting destructor</code> and take a look at the disassembly:</p> <pre><code>01341580 mov dword ptr [ebp-8],ecx 01341583 mov ecx,dword ptr [this] 01341586 call Test::~Test (134105Fh) 0134158B mov eax,dword ptr [ebp+8] 0134158E and eax,1 01341591 je Test::`scalar deleting destructor'+3Fh (134159Fh) 01341593 mov eax,dword ptr [this] 01341596 push eax 01341597 call operator delete (1341096h) 0134159C add esp,4 </code></pre> <p>while doing our recursion we are stuck at address <code>01341586</code>, and memory is actually released only at address <code>01341597</code>. </p> <p>Conclusion: In VS 2008, since destructor is just a method and all memory release code are injected into middle function (<code>scalar deleting destructor</code>) it is safe to call destructor recursively. But still it is not good idea, IMO.</p> <p><strong>Edit</strong>: Ok, ok. The only idea of this answer was to take a look at what is going on when you call destructor recursively. But don't do it, it is not safe generally.</p>
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    1. POCan a destructor be recursive?
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    1. COThis is still not even remotely safe: even though the destructor is "just" a member function, each time it returns it calls the destructors of any base classes and member variables (this is easy to test).
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      1. USJames McNellis
    2. COTesting the output of something is not an indication of the legality of any bit of code. What you get, at best, is the certain behavior of a certain compiler on a certain bit of code, but that has nothing to do with C++ as a language.
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    3. CO+1 for the testing attitude. I can still not imagine how you can have such an idea.
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