Incremental Linking

[Gerald Rogers <grogers at mail dot ipinfusion dot com>]

I am seeking help with performing an incremental link which will exclude all 
symbols except those I defined in the -retain-symbols-file filename option, 
and those which are unresolved.

I have a piece of software which has a common library, and on those systems 
which have a flat name space I get name conflicts.  I was wanting to link the 
library into each module instance which uses the library, and then link all 
of the modules into a single application.

As a test, I used the following setup.  This failed to exclude those symbols I 
did not want in the object.

file 1:
#include "stdlib.h"

int x;

extern int foo();

int func1()
{
   foo();
   printf("func1 x addr %x, x val %d\n", &x, x);
}


file 2:
#include "stdlib.h"

int x;

extern int foo();

int func2()
{
   foo();
   printf("func1 x addr %x, x val %d\n", &x, x);
}

file 3:
extern int x;

int foo()
{
  x = x + 1;
}

Symbols_file:
func1
func2

In the above files, I performed the following.

gcc -c file1.c
gcc -c file2.c
gcc -c file3.c

ld -r -retain-symbols-file symbol_file file1.0 file3.0 -o file_1.o

The output is a .o which contains all the symbols from file1.c and file3.c .

What I wanted to see was the symbols to contain only the following:
func1 from file1
printf from file1  (unresolved so should be included).

Is there any way to do this with incremental links.

I have managed to link into seperate objects when I did not include unresolved 
symbols (i.e. printf) without the -r option, and then link the seperate 
objects together.  However, when I include printf that means I have to link 
against the standard libraries, and I don't want multiple instances of the 
standard libraries.

Any help is greatly appreciated.

Thanks,

Gerald Rogers
IP Infusion, Inc.