CComObjectRootEx::m_pOuterUnknown

IUnknown* m_pOuterUnknown;

Remarks

Part of a union that accesses four bytes of memory.

union
{
   long m_dwRef;
   IUnknown* m_pOuterUnknown;
};

If the object is aggregated, the pointer to the outer unknown is stored in m_pOuterUnknown. If the object is not aggregated, the reference count accessed by AddRef and Release is stored in m_dwRef. 

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