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Q147735: FIX: ClassWizard Quits If Class Twice Derived from CRecord

Article: Q147735
Product(s): Microsoft C Compiler
Version(s): winnt:
Operating System(s): 
Keyword(s): kbwizard kbMFC kbVC400bug kbVC410bug kbVC420fix kbGrpDSTools kbNoUpdate
Last Modified: 06-MAY-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- The Microsoft Foundation Classes (MFC), used with:
   - Microsoft Visual C++ 32-bit Edition, versions 4.0, 4.1 
-------------------------------------------------------------------------------

SYMPTOMS
========

Under circumstances similar to the following, ClassWizard may cause an access
violation:

- You derive a class, CMyRecordset1, from CRecordset using ClassWizard.

- You derive another class, CMyRecordset2, from CRecordset using ClassWizard.

- You replace all occurrences of CRecordset in the .cpp and .h files for
  CMyRecordset2 with CMyRecordset1

The result is that CRecordset2 will be derived from CRecordset1. When ClassWizard
is invoked to view CMyRecordset2, an access violation may occur. This problem
has been verified with both CRecordset and CDaoRecordset.

RESOLUTION
==========

Leave occurrences of CRecordset in the ClassWizard comments. Particularly, don't
change:

     //{{AFX_FIELD(CRecordset2, CRecordset)

to:

     //{{AFX_FIELD(CRecordset2, CRecordset1)

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This problem was corrected in Visual C++, 32-bit
Edition, version 4.2.

Additional query words:

======================================================================
Keywords          : kbwizard kbMFC kbVC400bug kbVC410bug kbVC420fix kbGrpDSTools kbNoUpdate 
Technology        : kbAudDeveloper kbMFC
Version           : winnt:
Issue type        : kbbug
Solution Type     : kbfix

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