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Q87967: FIX: CVW 4.0 Does Not Work with Dynamically Loaded DLL

Article: Q87967
Product(s): Microsoft Programming Utilities
Version(s): 4.0,4.01
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 26-JUN-2001

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The information in this article applies to:

- Microsoft CodeView for Windows, versions 4.0, 4.01 
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SYMPTOMS
========

Microsoft CodeView for Windows (CVW) version 4.0 and 4.01 may not work with a
DLL that has been dynamically loaded, freed, and loaded again. Problems include
not stopping on existing breakpoints, not allowing new breakpoints, watches
displaying invalid or incorrect data, and mixed source/assembly mode showing the
wrong code.

CAUSE
=====

CVW associates source lines and symbols with addresses when programs and DLLs
are loaded into memory. When Windows loads, frees, and loads a DLL again, the
DLL may be loaded into a new area of memory. CVW is not updating the addresses
of the symbols when this occurs.

RESOLUTION
==========

If the DLL is loaded by another program before CVW is used, the DLL is not
loaded or freed by the program that is being debugged. Windows will not load
more than one copy of a DLL. It will just increase or decrease the instance
count of the DLL when the program is being debugged.

The solution to this problem is to create a stub program that loads the DLLs that
are being dynamically loaded. This program can be run before running CVW.


STATUS
======

Microsoft has confirmed this to be a problem in Microsoft CodeView for Windows
versions 4.0 and 4.01. This problem was corrected in CodeView version 4.1.

MORE INFORMATION
================

A dynamically loaded DLL is a DLL that is loaded using the LoadLibrary() Windows
API function.

Additional query words: 4.00 4.10 FreeLibrary

======================================================================
Keywords          : kb16bitonly 
Technology        : kbAudDeveloper kbCodeView kbCodeView400 kbCodeView401
Version           : :4.0,4.01
Solution Type     : kbfix

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