KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q117796: PRB: Incorrect Debug Information in 32-bit Object Module

Article: Q117796
Product(s): Microsoft Macro Assembler
Version(s): 6.1
Operating System(s): 
Keyword(s): kbtool
Last Modified: 11-FEB-2002

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

- Microsoft Macro Assembler (MASM), version 6.1 
-------------------------------------------------------------------------------

SYMPTOMS
========

When you step through assembly source code with a debugger, instructions do not
seem to execute properly. Switching to mixed assembly and source shows the
source code does not match up with the disassembled code.

CAUSE
=====

When you debug a Windows NT application containing an Object Module Format (OMF)
object module created with Microsoft Macro Assembler (MASM), version 6.1, the
source line number debug information is incorrect when converted to Common
Object File Format (COFF) by a 32-bit linker (such as the linker shipped with
Microsoft Visual C++, 32-bit edition). This results in lines in the source file
being incorrectly associated with points in the executable file.

RESOLUTION
==========

Assemble the assembly source file using the /coff switch, which will cause MASM
to generate a COFF object module.

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

COFF is the preferred object file format for Windows NT, and you should always
use the /coff switch when assembling source files for use in the Windows NT
operating system.

Additional query words: 6.10a 6.11 6.11a

======================================================================
Keywords          : kbtool 
Technology        : kbMASMsearch kbAudDeveloper kbMASM610
Version           : :6.1
Issue type        : kbprb

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.