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Q148509: PRB: A2108 Error When Using Simplified Segment Directives

Article: Q148509
Product(s): Microsoft Macro Assembler
Version(s): 6.0,6.1,6.11
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), versions 6.0, 6.1, 6.11 
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SYMPTOMS
========

When assembling code that uses simplified segment directives, the Macro
Assembler displays an error message similar to this one:

  error A2108: use of register assumed to ERROR

CAUSE
=====

This error can occur because of incorrect order of the .DATA and .CODE
directives in the assembly source code. The .DATA directive implies ASSUME
CS:ERROR. Any code that appears after the .DATA directive and attempts to
implicitly or explicitly use the CS register (such as JMP instructions or
labels) will generate this error.

RESOLUTION
==========

Make sure that a .CODE directive and not a .DATA directive precedes your
procedure definitions and any other instructions.

STATUS
======

This behavior is by design.

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

Sample Code to Reproduce Error
------------------------------

  ; Assemble options needed: none

  .MODEL small, c

  .CODE

  .DATA

  my_label:

  END

Additional query words: 6.00 6.10

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM600 kbMASM610 kbMASM611
Version           : :6.0,6.1,6.11

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

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