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Q79067: FIX: A2029 Incorrectly Generated If Operand = [ebx][ebx]

Article: Q79067
Product(s): Microsoft Macro Assembler
Version(s): 6.0
Operating System(s): 
Keyword(s): 
Last Modified: 04-MAY-2001

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The information in this article applies to:

- Microsoft Macro Assembler (MASM), version 6.0 
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SYMPTOMS
========

With the Microsoft Macro Assembler (MASM) 6.0, the following error is generated
incorrectly for instructions using the operand [ebx][ebx]:

  error A2029 : multiple base registers not allowed

For example:

  lea esi, [ebx][ebx]
  mov esi, [ebx][ebx]

RESOLUTION
==========

A workaround for this problem is to embed the opcode for the instruction
directly in the code. The sample code below demonstrates this method.

STATUS
======

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

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

Error A2029 will be incorrectly generated for the following program. The code
that should be generated for lea esi [ebx][ebx] is 8D 34 1B. Note that the
operand [ebx][ebx] is available only when using the .386 or .486 directives.

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

  ; Assembler options needed none

  .386
  .MODEL flat
  .STACK 4096

  CODE32 SEGMENT PUBLIC USE32
   main PROC near
      lea esi, [ebx][ebx]      ; Replace this by BYTE 8Dh, 34h, 1Bh
      ret
  main ENDP
  CODE32 ENDS

  END

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

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM600
Version           : :6.0
Solution Type     : kbfix

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

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