I discovered an interesting bug in an MFC multithreaded program. I found that when you delete a pointer to the worker thread's parameter (declared using new operator), the destructor of the class that is part of the parameter is called.

// This is global.
ClassA *pCA;

// This code is in the primary or main thread.


// Assume that clObject is a member variable and is an instance
// of a ClassA.

ptp->pCA = &clObject;

CWinThread *Thread = AfxBeginThread(ThreadFunction, ptp, ...);

// Assume everything works.
// Here is ThreadFunction

UINT ThreadFunction(LPVOID *pParams)
THREADPARAMS *ptp = reinterpret_cast<THREADPARAMS *>(pParams);

ClassA *pClassA = ptp->pCA;

// Here is the code that causes the bug.
// I studied Jeff Prosise book on MFC.
// Prosise deleted the new struct inside the worker thread.

delete ptp;

Okay. Lets get to the point. "delete ptp" calls ClassA destructor. I am not sure how to get this working.

My goal is to pass into a worker thread pointers to private data members of the primary thread (main) including primitive data type and ADT. I would like to know is the situation above normal or is there a flaw in my design?