winapi - Why does _get_heap_handle equal to GetProcessHeap?

Question

According to this article, CRT uses separate heap (is it private heap?), but this little example shows that CRT heap and Default heap are the same:

HANDLE heaps[64];
DWORD heapCount = GetProcessHeaps(64, heaps);    
for (int i = 0; i<heapCount; i++)
    printf("heap %d : [0x%x]
", i, heaps[i]);
printf("crt heap[0x%x], default heap[0x%x]
", _get_heap_handle(), GetProcessHeap());

In what cases GetProcessHeap and _get_heap_handle return different handles?

// Compiled with VS2012 (Platform toolset v110)

Answer 1

This is new for VS2012, the CRT now uses the default process heap to allocate from. Previous versions have always created their own heap.

A significant advantage of using the default heap is that interop with code in a DLL will be a lot easier, it can significantly reduce the trouble of having to use a DLL that has its own copy of the CRT linked-in. Assuming that copy is also 2012+ vintage of course.

A potential disadvantage is that it is more difficult to generate a meaningful diagnostic or cleanly shutdown when the process heap becomes corrupted, Windows also uses that heap. And memory corruption in your code can destabilize OS calls, the kind that doesn't involve kernel calls, anything is possible there. I can imagine a security risk as well, I assume that this choice was made once they felt comfortable with the secure CRT enhancements.