From: Hendrik Muhs <Hendrik.Muhs@student.uni-magdeburg.de>
To: gcc-help@gcc.gnu.org
Subject: Problem with static linking
Date: Fri, 18 Jan 2002 10:44:00 -0000 [thread overview]
Message-ID: <20020118104400.06PjispuQfqIQy_So7PMOCFP4RzSn_zyo6y4pLmh1u0@z> (raw)
Hi,
I have a problem with static linking. Please look at the following example.
The main programm foo "dlopens" the shared library bar and calls the function
in bar.
If I compile at least bar.c or foo.c not static:
gcc -o foo foo.c -ldl
gcc -shared -o bar.so bar.c
or
gcc -static -o foo foo.c -ldl
gcc -shared -o bar.so bar.c
or
gcc -o foo foo.c -ldl
gcc -shared -o bar.so bar.c -Wl,-static
it works. But if compile both static:
gcc -static -o foo foo.c -ldl
gcc -shared -o bar.so bar.c -Wl,-static
I get a segfault(in malloc):
hendrik@tux:~> ./foo
we are in bar
Segmentation fault
I tried it with different versions of gcc: 2.95.3, 3.0.3(both SuSE Linux 7.3)
and 2.96(Redhat Linux 7.2)
the code:
//foo.c
#include <stdio.h>
#include <dlfcn.h>
int main (void)
{
void *lib;
int (*sym)(void);
lib = dlopen("./bar.so", RTLD_NOW);
if (!lib) {
fputs (dlerror(), stderr);
exit(1);
}
sym = dlsym(lib, "bar");
(*sym)();
dlclose(lib);
return 0;
}
//bar.c
#include <stdlib.h>
#include <malloc.h>
int bar(void)
{
char *buf;
printf("we are in bar\n");
buf = malloc(5);
printf("return to foo\n");
return 0;
}
Why does it segfaults?
Thanks in advance,
Hendrik
next reply other threads:[~2002-01-18 18:44 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-01-18 10:44 Hendrik Muhs [this message]
2002-01-18 10:44 Hendrik Muhs
[not found] <200201181844.SAA08954@crotus.sc.intel.com>
2002-01-18 15:51 ` Robert A Nesius
2002-01-19 0:54 ` Hendrik Muhs
2002-01-19 0:54 ` Hendrik Muhs
[not found] <478231340907151937x4f1059f8l4545bb071441c9f9@mail.gmail.com>
[not found] ` <m3fxcx70qi.fsf@google.com>
2009-07-16 4:30 ` Zachary Turner
2009-07-16 5:46 ` Ian Lance Taylor
2009-07-16 6:28 ` Zachary Turner
2009-07-16 7:07 ` Ian Lance Taylor
2009-07-16 7:52 ` Zachary Turner
2009-07-16 8:20 ` Ian Lance Taylor
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