DOCUMENT:Q117796  11-FEB-2002  [masm]
TITLE   :PRB: Incorrect Debug Information in 32-bit Object Module
PRODUCT :Microsoft Macro Assembler
PROD/VER::6.1
OPER/SYS:
KEYWORDS:kbtool

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The information in this article applies to:

 - Microsoft Macro Assembler (MASM), version 6.1 
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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

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

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