DOCUMENT:Q120068  04-MAY-2001  [masm]
TITLE   :PRB: H2INC Does Not Handle #undef
PRODUCT :Microsoft Macro Assembler
PROD/VER::6.1,6.11
OPER/SYS:
KEYWORDS:

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

 - Microsoft Macro Assembler (MASM), versions 6.1, 6.11 
-------------------------------------------------------------------------------

SYMPTOMS
========

The H2INC utility does not appear to handle #undef correctly. For example, the
following code fragment causes "error A2005: symbol redefinition: test2" to
appear:

      #define test2  2
      #if test2 == 2
         #undef test2
         #define test2 3
      #endif

CAUSE
=====

This behavior is by design.

The following .INC file is generated for the fragment listed in the "SYMPTOMS"
section:

       option expr32
       option casemap:none

       ; Begin of file xxx.h
       test2          EQU          2t
       test2          EQU          3t
       ; End of file xxx.h

NOTE: In MASM, constants defined with EQU cannot be redefined.

RESOLUTION
==========

A #define can define "text equates" as well as "numeric equates." In the case of
numeric constants, use an editor to change the "EQU" to a "=".

Additional query words: 6.10 6.11

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM610 kbMASM611
Version           : :6.1,6.11

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

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