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Q72887: FIX: Using a Higher Processor Directive in a Macro Causes A2006

Article: Q72887
Product(s): Microsoft Macro Assembler
Version(s): MS-DOS:6.0,6.0a,6.0b
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 
-------------------------------------------------------------------------------

SYMPTOMS
========

When you attempt to use a symbol in your assembly code without defining it
first, the Microsoft Macro Assembler (MASM) generates the following error:

  error A2006: undefined symbol : 'identifier'

However, MASM may also incorrectly generate this error when you use a processor
directive in a macro if the processor specified is higher than the one currently
defined.

RESOLUTION
==========

To work around the problem, declare a processor type of sufficient level to
execute the instructions in the macro before calling the macro. The comment in
the sample code below demonstrates this by declaring the .286 directive before
the macro is called.

STATUS
======

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

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

The sample code below may be used to illustrate this problem. The default
processor directive is .8086. When the macro is called, a LEAVE instruction is
used that requires the .286 processor. However, with the .286 directive in the
macro definition, the following error is generated by the assembler:

  file.asm(14): error A2006: undefined symbol : s my_proc(2): Macro Called From
  file.asm(14): Main Line Code

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

  ;Assemble options needed: /c

  .MODEL small
  .8086
  ;.286    ;Uncomment this directive for workaround.

  my_proc MACRO  s
     .286
     enter s, 0
     .8086
  ENDM

  .STACK 4096

  .CODE
  start:
     my_proc 5
     mov ax, 4C00h
     int 21h
  END start

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

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM600 kbMASM600a kbMASM600b
Version           : MS-DOS:6.0,6.0a,6.0b
Solution Type     : kbfix

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

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