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Q77945: FIX: Alignment in Nested Structures Incorrect in MASM 6

Article: Q77945
Product(s): Microsoft Macro Assembler
Version(s): MS-DOS:6.0
Operating System(s): 
Keyword(s): 
Last Modified: 04-MAY-2001

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The information in this article applies to:

- Microsoft Macro Assembler (MASM), version 6.0 
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SYMPTOMS
========

The Microsoft Macro Assembler (MASM) version 6.0 does not pad aligned nested
structures correctly. The list file shown below illustrates this problem.

RESOLUTION
==========

Manually padding the structure definition to force the nested structure to have
the correct alignment will work around this problem.

STATUS
======

Microsoft has confirmed this to be a problem in MASM version 6.0. This problem
was corrected in MASM version 6.0a.

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

The following code can be used to demonstrate the problem.

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

  ; Assemble options needed: /c /Fl

  .MODEL small, C

  .DATA
  struct1 STRUCT 2          ; Alignment value is 2
      field1 WORD ?           ; Offset is 0
      field2 BYTE ?           ; Offset is 2
  struct1 ENDS

  struct2 STRUCT 2          ; Alignment value is 2
      field3 BYTE ?           ; Offset is 0
      nested struct1 <?, ?>   ; Offset is 1, should
  struct2 ENDS              ;   be padded to 2

  END

Additional query words: 6.00 buglist6.00 fixlist6.00a

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM600
Version           : MS-DOS:6.0

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

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