Re: [Xenomai-help] Xenomai 2.5.0: rt_task_shadow fails when libnative is statically linked.

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Gilles Chanteperdrix wrote:
> Henri Roosen wrote:
>> Hi all,
>>
>> I get segmentation fault when calling rt_task_shadow. Actually
>> somewhere in the pthread library called from sigshadow_install_once();
>>
>> This only happens on Xenomai 2.5 when libnative is statically linked.
>> Tested ok on 2.4.10 both dynamically and statically linked. I use
>> kernel version 2.6.30.10, xenomai 2.5.0 on x86.
>>
>> Any idea what is wrong?
>>
>> Reproduced it with basic app that is attached to this email. Compiled with:
>> gcc -D_GNU_SOURCE -D_REENTRANT -Wall -pipe -D__XENO__
>> -I/usr/xenomai/include tst_basic.c -o tst_basic
>> /usr/xenomai/lib/libnative.a -lpthread
>>
>> Segfailt in dmesg on xenomai 2.5.0:
>> tst_basic_2.5[1351]: segfault at 0 ip b7ff5a54 sp bfc9b46c error 4 in
>> libpthread-2.9.so[b7feb000+13000]
> 
> Ok. Reproduced here. It looks like xeno_sigshadow_install and
> xeno_sigshadow_installed have no address. I am on it.

The following patch seems to fix the issue for me.

diff --git a/include/asm-generic/bits/sigshadow.h b/include/asm-generic/bits/sigshadow.h
index 5a32762..e07ce00 100644
--- a/include/asm-generic/bits/sigshadow.h
+++ b/include/asm-generic/bits/sigshadow.h
@@ -4,10 +4,10 @@
 #include <pthread.h>
 #include <signal.h>

-extern pthread_once_t __attribute__((weak)) xeno_sigshadow_installed;
-extern struct sigaction __attribute__((weak)) xeno_saved_sigshadow_action;
+extern pthread_once_t xeno_sigshadow_installed;
+extern struct sigaction xeno_saved_sigshadow_action;

-void __attribute__((weak)) xeno_sigshadow_install(void);
+void xeno_sigshadow_install(void);

 static inline void sigshadow_install_once(void)
 {


-- 
					    Gilles.