Q26796: FIX: "Operand Expected" Error Message

Article: Q26796
Product(s): Microsoft Macro Assembler
Version(s): 5.0,5.1,5.1a
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

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

- Microsoft Macro Assembler (MASM), versions 5.0, 5.1, 5.1a 
-------------------------------------------------------------------------------

SYMPTOMS
========

The expression 'PUSH DWORD PTR OFFSET alabel' causes the Microsoft Macro
Assember (MASM) versions 5.0, 5.1, and 5.1a to generate the error message:

  error A2027: Operand expected

RESOLUTION
==========

The line 'PUSH DWORD PTR (OFFSET alabel)' works correctly. Since OFFSET is a
unary operator, it should not require parentheses.

STATUS
======

Microsoft has confirmed this to be a problem in MASM versions 5.0, 5.1, and
5.1a. This problem was corrected in MASM version 6.0.

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

It is important to note that the operating system that your program is running
on must be capable of supporting 32 bit code segments to be able to run code in
32 bit segments. Most PC based operating systems such as MS-DOS 5.0, Windows
3.0, and OS/2 1.x do not provide support for 32 bit code segments. Newer
operating systems and DOS extender packages may provide this support.

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

  ; Assemble options needed: none

  .MODEL small
  .386

  .STACK 1024

  seg32 SEGMENT USE32
  a32label DW 4321h
  seg32 ENDS

  .CODE
  start:
    ;push DWORD PTR (OFFSET a32label) ;This is the MASM 5.0,
                                      ;5.1, and 5.1a workaround
    push DWORD PTR OFFSET a32label
    mov ax, 4C00h
    int 21h

  END start

Additional query words: 5.00 5.10 5.10a buglist5.00 buglist5.10 buglist5.10a fixlist6.00

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM500 kbMASM510a
Version           : :5.0,5.1,5.1a
Solution Type     : kbfix

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

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 1986-2002.