From mboxrd@z Thu Jan  1 00:00:00 1970
From: leslie.polzer@gmx.net
Subject: Problem with pointer to external function
Date: Fri, 1 Jul 2005 12:30:26 +0200
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Hello list,

why do it get the segfault below? What's wrong?


[sky@paktahn ~/code/cbtest]% cat main.c     =20
#include <stdio.h>

typedef void (*callback)();

extern callback cb;

int
main (int argc, char** argv)
{
        cb();

        return(0);
}

[sky@paktahn ~/code/cbtest]% cat defhandlers.c      =20
void cb()
{
}

[sky@paktahn ~/code/cbtest]% gcc main.c defhandlers.c -ggdb
[sky@paktahn ~/code/cbtest]% gdb ./a.out=20
GNU gdb 6.3
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain condition=
s.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i686-pc-linux-gnu"...Using host libthread_db li=
brary "/lib/tls/libthread_db.so.1".

(gdb) run
Starting program: /home/sky/code/cbtest/a.out=20

Program received signal SIGSEGV, Segmentation fault.
0x5de58955 in ?? ()
(gdb) bt full
#0  0x5de58955 in ?? ()
No symbol table info available.
#1  0x08048367 in main (argc=3D1, argv=3D0xbffff634) at main.c:10
No locals.
(gdb)


Regards,

Leslie

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