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Q94911: BUG: ALIGN Directive Placement Changes EXE File Size

Article: Q94911
Product(s): Microsoft Macro Assembler
Version(s): 6.1,6.11,6.1a
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

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

- Microsoft Macro Assembler (MASM), versions 6.1, 6.1a, 6.11 
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SYMPTOMS
========

In an application developed with the Microsoft Macro Assembler (MASM), placing
the ALIGN directive before data in a _BSS segment increases the sizes of the
object module and of the executable file.

CAUSE
=====

When the ALIGN directive appears at the beginning of a segment, the assembler
places the unitialized _BSS segment into the executable file.

RESOLUTION
==========

To work around this problem, modify the source code to remove the ALIGN
directive from the beginning of the segment. According to the design of the
assembler, the ALIGN directive does not have any effect at the beginning of a
segment. The first item of the segment is aligned according to the alignment
parameter in the SEGMENT statement.

STATUS
======

Microsoft has confirmed this to be a problem in MASM versions 6.1, 6.1a, and
6.11. We are researching this problem and will post new information here in the
Microsoft Knowledge Base as it becomes available.

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

Sample Code
-----------

  ; Assemble options needed: None

  DOSSEG

  _text SEGMENT para public 'CODE'
  start:
     nop
  _text ENDS

  _bss SEGMENT para public '_BSS'
     align 4
     dw ?
  _bss ENDS

  stk SEGMENT para stack 'STACK'
     dw ?
  stk ENDS

  END start

Additional query words: 6.10 6.10a 6.11 buglist6.10 buglist6.10a buglist6.11

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM610 kbMASM611 kbMASM610a
Version           : :6.1,6.11,6.1a

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

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