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Q39523: How to Declare Externals in MASM

Article: Q39523
Product(s): Microsoft Macro Assembler
Version(s): 5.0,5.1,6.0,6.0a,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, 6.0, 6.0a, 6.0b 
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SUMMARY
=======

The following are the rules for declaring externals in MASM:

1. NEAR code labels must be declared in the code segment from which they are
  accessed.

2. Although FAR code labels can be declared anywhere in the source code, it is
  recommended they be declared outside of any segments. You may declare them at
  the top of your program after the .MODEL directive.

3. Any external data in the DGROUP data segment, must be declared in the segment
  in which it is defined. You may need to create a dummy data segment for the
  external declaration.

4. Data items declared in .FARDATA segment, that need to be referenced as
  externals, should be declared out of any segments. Otherwise, fixup-overflow
  errors may occur during linking. Note: This conflicts with the rules
  indicated on Page 162 of "Microsoft Macro Assembler Programmer's Guide" for
  Versions 5.x.

Additional query words: kbinf 5.00 5.10 6.00 6.00a 6.00b

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

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