Q72849: FIX: L1126 Link Error May Be Caused By EXPORT in PROC Definition

Article: Q72849
Product(s): Microsoft Macro Assembler
Version(s): MS-DOS: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 6.0, 6.0a, 6.0b 
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SYMPTOMS
========

When creating an exported function with the Microsoft Macro Assembler (MASM)
version 6.0, 6.0a, or 6.0b, the EXPORT keyword can be used in a procedure
definition and MASM will automatically generate the correct .OBJ record to add
it to the export table for the .EXE (or DLL). This is useful when creating a
procedure in a DLL that is called from outside the DLL, when creating a callback
procedure in an .EXE, or when defining a procedure as residing in an IOPL
segment with OS/2.

However, there is a problem when the EXPORT keyword is used in the latter case.
When creating an IOPL function, you must declare the number of words that will
be required to hold the parameters for the function. The operating system then
uses this value to build the stack that the IOPL function will run on. You
normally do this by adding the word count after the function name in the EXPORT
section of the associated .DEF file. For example, the .DEF file may contain the
following:

     EXPORTS _Func 3

CAUSE
=====

The problem results when you then use the EXPORT keyword in MASM for the
procedure definition for the IOPL function as follows:

     Func PROC EXPORT, arg1:WORD, arg2:WORD, arg3:WORD

MASM will generate an EXPDEF (EXPort DEFinition) record that lists the parameter
word count as zero. If you then link with the .DEF file that correctly lists the
word count as three, the linker will return the following error message:

  fatal error L1126: conflicting pwords value

RESOLUTION
==========

The workaround is to change the EXPORT keyword in the procedure definition to
PUBLIC.

STATUS
======

Microsoft has confirmed this to be a problem in MASM versions 6.0, 6.0a, and
6.0b. This problem was corrected in MASM for MS-DOS version 6.1.

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

TEST.ASM
--------

  ;; Assemble options needed: none

  .MODEL large
  .286

  .CODE
  Func PROC C EXPORT, arg1:PTR DWORD, arg2:WORD
  Func ENDP
  END Func

TEST.DEF
--------

  ; Module definition file for linking

  NAME Test

  EXPORTS
     _Func 3

Additional query words: 6.00 6.00a 6.00b buglist6.00 buglist6.00a buglist6.00b fixlist6.10

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Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM600 kbMASM600a kbMASM600b
Version           : MS-DOS:6.0,6.0a,6.0b
Solution Type     : kbfix

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