KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q40485: Error L2025: Symbol Defined More than Once

Article: Q40485
Product(s): See article
Version(s): 5.10   | 5.10
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | | mspl13_basic
Last Modified: 20-JAN-1989

Problem:

I cannot link a function name in my object file with a library
containing that same function name and have the resulting EXE call my
function and not the library's.

I am using /NOE; however, I receive the following error:

(...): error L2025: (my function name) : symbol defined more than once
 pos: (some number) Record type: 53E8

Response:

You can only perform this task if the function name is an individual
module. The following procedure demonstrates the error:

1. Create a file CALL.C that calls functions A() and B().

2. Create functions A() and B() in fileA.c and fileB.c, and compile
   them to objects.

3. Do the following to create TEST.LIB:

      LIB TEST +fileA +fileB, test.lst

4. Change B() in fileB.c and compile the following:

      cl call.c fileB.c test.lib /link /NOE /INF

   You will have an EXE that calls A() from the library and B() from
   your modified fileB.c.

5. Combine fileA.c and fileB.c into one file called TEST.C.

6. Compile to object code.

7. Delete the old TEST.LIB, and do the following:

      LIB TEST +test, test.lst

   (Normally you would change fileB.c, but this is not necessary here.)

      cl call.c fileB.c test.lib /link /NOE /INF

You will receive the following error:

TEST.LIB(test.c) : error L2025: _B : symbol defined more than once
 pos: 13E Record type: 53E8
There was 1 error detected

When you encounter this error, it is usually because the function you
are trying to overwrite is part of a set appearing in one module.

The library listing looks as follows in the first case:

_A................fileA             _B................fileB

fileA             Offset: 00000010H  Code and data size: 95H
  _A

fileB             Offset: 000002a0H  Code and data size: 92H
  _B

You will be able to replace A() or B(). The listing in the
second example looks as follows:

_A................test              _B................test

test              Offset: 00000010H  Code and data size: deH
  _A                _B

You will not be able to replace either A() or B() without removing the
TEST module with the LIB utility. You may have to provide replacements
for both functions and not just the one you want to change. For more
information, query on the following words in this KnowledgeBase:

   L2029 unresolved externals

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.