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Q35803: DOCERR: External Addresses in "=" Directive

Article: Q35803
Product(s): Microsoft Macro Assembler
Version(s): 5.0,5.1,5.1a,6.0,6.0a,6.0b
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

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The information in this article applies to:

- Microsoft Macro Assembler (MASM), versions 5.0, 5.1, 5.1a 
- Microsoft Macro Assembler (MASM), versions 6.0, 6.0a, 6.0b 
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SYMPTOMS
========

On page 214, section 11.1.1, of the "Microsoft Macro Assembler 5.1 Programmer's
Guide", the documentation indicates that the equal sign (=) directive may be
used with expressions that evaluate to an address. However, if the address
refers to an external label, MASM 5.1 and 5.1a will generate the error:

  error A2052: Improper operand type

MASM 6.0, 6.0a, and 6.0b will generate the error:

  error A2026: constant expected

CAUSE
=====

MASM has a restriction that the (=) directive can not be used on an external
address.

RESOLUTION
==========

You can use the EQU directive to create an alias for an external address.

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

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

  ; Assemble options needed: none

  EXTRN buf1:BYTE
  buf2 = buf1

  END

Additional query words: 5.10 5.10a 6.00 6.00a 6.00b

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM600 kbMASM500 kbMASM600a kbMASM510a kbMASM600b
Version           : :5.0,5.1,5.1a,6.0,6.0a,6.0b

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