Re: Application crashes when COM DLL returns OLE error

From:
"Igor Tandetnik" <itandetnik@mvps.org>
Newsgroups:
microsoft.public.vc.atl
Date:
Mon, 17 Jul 2006 07:47:23 -0400
Message-ID:
<ewaF3aZqGHA.148@TK2MSFTNGP04.phx.gbl>
<shreyas.saxena@gmail.com> wrote in message
news:1153111547.657806.141120@s13g2000cwa.googlegroups.com

  HRESULT hr = CComObject<CClassName>::CreateInstance(&pObject);
  if ( SUCCEEDED(hr))
  {
pObject->AddRef();
hr = pObject->QueryInterface(iid, ppv);
        hr = pObject->Release();


Release() does not return HRESULT, assigning the return value to hr
makes no sense. It also masks any error that might have been returned by
QueryInterface.

So, if there is an error in the CreateInstance of CClassName, it
should return the Error along with the Error Code. But it gives an
"Unhandled Exception" error with the Description as "Access
Violation". After this the application crashes.


Why don't you step through this code under debugger and see exactly
where it crashes?
--
With best wishes,
    Igor Tandetnik

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