Q30576: Fix-Up Overflow Caused By Extrn Statements and .Fardata

Article: Q30576
Product(s): Microsoft Macro Assembler
Version(s): 5.1
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 5.1 
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SUMMARY
=======

The following assembler modules produce a fix-up overflow error message during
linking.

When linking these two modules together, the .fardata-simplified segment
directive will cause a link-error fix-up overflow.

Every module with a .fardata segment is defining a different .fardata segment.
The linker will keep the segments separate. Therefore, declaring the fvar
variable external in module 2 generates the problem. The extrn far data item,
fvar, should be declared outside the .fardata segment.

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

Module 1

  .model large
  .stack
  .data
  public gvar
  .fardata
  public fvar
  fvar  db  55h

  .code
  extrn t2:proc
  start: mov ax,@DATA
         mov ds,ax
         mov ax,@FARDATA
         mov es,ax

         call dword ptr t2
  end start

Module 2

  .model large
  .data
  extrn gvar:byte
  .fardata
  extrn fvar:byte

  .code
      public t2
  t2  proc   far
      mov bl, es:fvar
      ret FAR
  t2  endp
      end

Additional query words: 5.10

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Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510
Version           : :5.1
Solution Type     : kbfix

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