I have written code using XS without problems. In all those programs I have written the C-code into the xs file. But now, I have tried to use a function defined in an other shared-object file, and although the building process does not print errors, when I use the pm-module (in "make test" for example) it returns "undefined symbol" error. During the shared-object building, make-process shows me the following message: "linker input file unused because linking not done". This warning explains the previous error. In C-code the symbols are resolved in executable files, not in shared-objects. But Perl import C-code as a shared-object, and so how can I resolve this problem??

-----------------------/tmp/prova2/helloworld/Makefile-----------------------
# Makefile

MODULE=helloworld
TYPEMAP=/usr/local/lib/perl5/5.8.7/ExtUtils/typemap
XSUBPP=/usr/local/lib/perl5/5.8.7/ExtUtils/xsubpp
PERLCORE=/usr/local/lib/perl5/5.8.7/i686-linux/CORE
CC=gcc

.PHONY: init clean

all :             init libhelloworld.so
                  
init :            
                  perl -e "use Devel::PPPort; use ExtUtils::Constant q
+w (WriteConstants); \
                  Devel::PPPort::WriteFile(); WriteConstants(NAME => '
+$(MODULE)')"

libhelloworld.so : helloworld.o
                  $(CC) -shared helloworld.o -o $@
                  
helloworld.c :    helloworld.xs
                  perl $(XSUBPP) -typemap $(TYPEMAP) helloworld.xs >$@

helloworld.o :    helloworld.c
                  $(CC) -Wall -fPIC -I$(PERLCORE) -I. -c helloworld.c 
+-Wl,-rpath,. -o $@

clean :           
                  rm -f helloworld.o helloworld.c const-c.inc const-xs
+.inc ppport.h 

clean-all :       clean
                  rm -f libhelloworld.so

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-----------------------/tmp/prova2/helloworld/helloworld.xs-----------------------
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include "ppport.h"

#include <helloworld.h>

#include "const-c.inc"

#include "extlibs/myprint.h"
//#include "extlibs/myprint.c"


MODULE = helloworld           PACKAGE = helloworld

INCLUDE: const-xs.inc

void
helloworld_proc()
      CODE:
      printf ("Helloworld\n");
      boxing_print ("Helloworld");

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-----------------------/tmp/prova2/helloworld/helloworld.pm-----------------------
package helloworld;

use 5.008007;
use strict;
use warnings;
use Carp;

require XSLoader;

our $VERSION = '0.01';


XSLoader::load('helloworld', $VERSION);


1;

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-----------------------/tmp/prova2/helloworld/extlibs/Makefile---------------------
# Makefile


localpath=/tmp/prova2/helloworld/extlibs
LD_RUN_PATH=$(localpath)
CC=gcc


.PHONY: clean clean-all

all :             libmyprint.so test

myprint.o :       myprint.c
                  $(CC) -c myprint.c -Fpic -o $@

libmyprint.so :   myprint.o myprint.h
                  $(CC) -shared myprint.o -o $@
                  
test :            test.c
                  $(CC) -Wall test.c -I$(localpath) -L$(localpath) -Wl
+,-rpath,$(localpath) -lmyprint -o $@
                  
clean :
                  rm -f *.o

clean-all :       clean
                  rm -f *.so test

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-----------------------/tmp/prova2/helloworld/extlibs/myprint.c----------------------
#include "stdio.h"
#include "string.h"
#include "myprint.h"

void boxing_print (char *st) {
      int t=0;

      for (t=0; t<strlen(st); t++) printf ("-");
      printf ("\n%s\n", st);
      for (t=0; t<strlen(st); t++) printf ("-");
      printf ("\n");
      return;
}

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-----------------------/tmp/prova2/helloworld/extlibs/myprint.h----------------------- 
void boxing_print (char*);

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Thank you for your help. Best regards Warlock

In reply to shared-obj linking in xs-module by warlock

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