DOCUMENT:Q30576  04-MAY-2001  [masm]
TITLE   :Fix-Up Overflow Caused By Extrn Statements and .Fardata
PRODUCT :Microsoft Macro Assembler
PROD/VER::5.1
OPER/SYS:
KEYWORDS:

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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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