System Access Error

[4Codehelp]

I have a code in VC++ that gives this particular error on exiting the program while executing in release mode.

Error:
An unhandled exception of type 'System.AccessV iolationExcepti on' occurred in Unknown Module.

Additional information: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.

The execution breaks at one of these places:

1. file name oleinit.cpp
[code=cpp]
if (pThread != NULL)
{
// destroy message filter (may be derived class)
delete pThread->m_pMessageFilt er;
pThread->m_pMessageFilt er = NULL; // This is the line where execution breaks
}[/code]

2. File name cmdtarg.cpp
[code=cpp]
CCmdTarget::~CC mdTarget()

{

#ifndef _AFX_NO_OLE_SUP PORT

if (m_xDispatch.m_ vtbl != 0)

((COleDispatchI mpl*)&m_xDispat ch)->Disconnect() ; //This is the line where error is indicated

ASSERT(m_dwRef <= 1);

#endif

m_pModuleState = NULL;

}
[/code]
The same doesnot happen when i execute the program in debug mode. Also when i execute the program throught the executable the exiting doesnot give this error. Can someone please help.

[weaknessforcats]

This code:

if (pThread != NULL)
{
// destroy message filter (may be derived class)
delete pThread->m_pMessageFilt er;
pThread->m_pMessageFilt er = NULL; // This is the line where execution breaks
}

Do you know that m_pMessageFilte r points at a heap allocation??

Most likely, the code is breaking on the delete.

[4Codehelp]

This code:


Do you know that m_pMessageFilte r points at a heap allocation??

Most likely, the code is breaking on the delete.

Hi

Thanks for the reply. I get this error only when i am executing the code through the development environment in release mode. The problem doesnot arise when i use the exe file directly....

Is it possible that I am using some memory used by the envt itself?

Kind regards

[weaknessforcats]

((COleDispatchI mpl*)&m_xDispat ch)->Disconnect() ; //This is the line where error is indicated

You are certain that m_xDispatch is, in fact, a COleDispatchImp l object???

Why not use a C++ cast that is not the meatax of the C cast?

Maybe:
[code=cpp]
COleDisparchImp l* rval = static_cast<COl eDisparchImpl*> (&m_xDispatch );
[/code]

and see it that compiles. No run time check but better than a C cast.

Then I would enable RTTI and try:

[code=cpp]
COleDisparchImp l* rval = dynamic_cast<CO leDisparchImpl* > (&m_xDispatch );
if (!rval)
{
//you have a problem
return; //bail
}
rval->Disconnect() ;
[/code]