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Q102432: FIX: Incorrect RET Generated for PROC when EPILOGUE:NONE

Article: Q102432
Product(s): Microsoft Macro Assembler
Version(s): 6.0,6.0a,6.0b,6.1,6.1a
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

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

- Microsoft Macro Assembler (MASM), versions 6.0, 6.0a, 6.0b, 6.1, 6.1a 
-------------------------------------------------------------------------------

SYMPTOMS
========

When Microsoft Macro Assembler (MASM) processes source code for an application,
it may generate the incorrect form for a RET instruction in a PROC.
Specifically, the assembler generates a RET 4 instruction instead of a RET
instruction when the source code contains a RET instruction.

CAUSE
=====

The source code uses the OPTION EPILOGUE statement multiple times to set the
EPILOGUE macro to NONE.

RESOLUTION
==========

Modify the source code to specify RET 0. The assembler translates this
expression into a RET instruction.

STATUS
======

Microsoft has confirmed this to be a problem in MASM versions 6.0, 6.0a, 6.0b,
6.1, and 6.1a. This problem was corrected in MASM for MS-DOS version 6.11.

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

The following code example demonstrates this problem:

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

  ; Assembler options needed: /c /Fl /Sa

  .MODEL small, Pascal

  _text SEGMENT

  OPTION EPILOGUE:NONE
  p0 PROC parm1:DWORD
      ret                 ; This correctly generates a RET
  p0 ENDP

  OPTION EPILOGUE:EpilogueDef
  p1 PROC parm1:DWORD
      ret                 ; This correctly generates a RET 4
  p1 ENDP

  OPTION EPILOGUE:NONE
  p2 PROC parm1:DWORD
      ret                 ; This incorrectly generates a RET 4
  p2 ENDP

  _text ENDS

  END

Additional query words: 6.00 6.00a 6.00b 6.10 6.10a buglist6.00a buglist6.00b buglist6.10 buglist6.10a fixlist6.11

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM600 kbMASM610 kbMASM610a kbMASM600a kbMASM600b
Version           : :6.0,6.0a,6.0b,6.1,6.1a
Solution Type     : kbfix

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