FIX: Incorrect RET Generated for PROC when EPILOGUE:NONE

• Microsoft Macro Assembler for MS-DOS, versions 6.0, 6.0a, 6.0b, 6.1, 6.1a
• Microsoft Macro Assembler for OS/2, versions 6.0, 6.0a, 6.0b

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 :
Version : :6.0,6.0a,6.0b,6.1,6.1a
Platform :
Issue type :