Q64535: FIX: Incorrect Code Generated for IRET With PROC USES

Article: Q64535
Product(s): Microsoft Macro Assembler
Version(s): MS-DOS:5.1,5.1a
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

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The information in this article applies to:

- Microsoft Macro Assembler (MASM), versions 5.1, 5.1a 
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SYMPTOMS
========

A procedure that uses the USES keyword cannot return by using IRET. The USES
statement pushes the specified registers on the stack upon entry and pops them
before exiting a procedure. If the USES keyword is used with a procedure that
ends with an IRET instruction, the pushes will be generated for the procedure,
but the pops will not.

STATUS
======

Microsoft has confirmed this to be a problem in MASM versions 5.1 and 5.1a. This
problem has been corrected in MASM version 6.0.

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

The following code demonstrates the problem. The di, si, and bp registers will
be pushed onto the stack, but not popped.

Source Code:
------------

  ; Compile options needed: none

           .model large, c

           .code

     first PROC far uses di si bp
           MOV si,3
           MOV di,4
           IRET
     first ENDP

           END first

Additional query words: 5.10 5.10a buglist5.10 buglist5.10a fixlist6.00

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Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM510a
Version           : MS-DOS:5.1,5.1a
Solution Type     : kbfix

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