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Q120067: FIX: .IF with Multiple Tests Adds a JMP Instruction

Article: Q120067
Product(s): Microsoft Macro Assembler
Version(s): 6.1
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 6.1 
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SYMPTOMS
========

If two or more values known at assembly time evaluate as TRUE, .IF (below) will
add a JMP instruction. In this first example, only the NOP is assembled:

     .IF 1
        nop
     .ENDIF

In this second example, a JMP instruction is added:

     .IF 1 || 3
        nop
     .ENDIF

If you use a register, as in this third example, the result is a conditional JMP
to the location following the .IF:

     .IF ax || 3
        nop
     .ENDIF

The code runs as expected, despite the extra instructions.

RESOLUTION
==========

To eliminate the extra generated code, replace the "||" with an "OR".

STATUS
======

Microsoft has confirmed this to be a bug in MASM version 6.1. This problem was
corrected in MASM version 6.11.

Additional query words: 6.10 buglist6.10 fixlist6.11

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM610
Version           : :6.1
Solution Type     : kbfix

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

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