[Buildroot] [PATCH 1/1] package/xenomai: fix build with glibc >= 2.34

[Fabrice Fontaine]

Fix the following build failure with glibc >= 2.34:

In file included from timerobj.c:32:
In function 'threadobj_set_current',
    inlined from 'server_prologue' at timerobj.c:94:2:
../../include/copperplate/threadobj.h:252:9: error: 'pthread_setspecific' expecting 1 byte in a region of size 0 [-Werror=stringop-overread]
  252 |         pthread_setspecific(threadobj_tskey, thobj);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes:
 - http://autobuild.buildroot.org/results/ed93f916eda304b30f320816c85d1b0d4488c699

Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
---
 ...id-addresses-for-pthread_setspecific.patch | 57 +++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 package/xenomai/3.0.10/0003-lib-cobalt-copperplate-Use-valid-addresses-for-pthread_setspecific.patch

diff --git a/package/xenomai/3.0.10/0003-lib-cobalt-copperplate-Use-valid-addresses-for-pthread_setspecific.patch b/package/xenomai/3.0.10/0003-lib-cobalt-copperplate-Use-valid-addresses-for-pthread_setspecific.patch
new file mode 100644
index 0000000000..0c39a4ecf7
--- /dev/null
+++ b/package/xenomai/3.0.10/0003-lib-cobalt-copperplate-Use-valid-addresses-for-pthread_setspecific.patch
@@ -0,0 +1,57 @@
+From 627d488db3aa71406e32d4d8934629e8b0f35905 Mon Sep 17 00:00:00 2001
+From: Jan Kiszka <jan.kiszka at siemens.com>
+Date: Sat, 16 Oct 2021 15:46:33 +0200
+Subject: [PATCH] lib/{cobalt,copperplate}: Use valid addresses for
+ pthread_setspecific
+
+glibx 2.34 and newer annotated pthread_setspecific in a way that gcc-11
+complains about non-NULL pointers that are outside of what is considered
+valid. So use dummy addresses instead. namely the related pthread keys.
+Those pointers will never be dereferenced in both use cases.
+
+See also https://sourceware.org/bugzilla/show_bug.cgi?id=28458.
+
+Reported-by: Vitaly Chikunov <vt at altlinux.org>
+Signed-off-by: Jan Kiszka <jan.kiszka at siemens.com>
+
+[Retrieved from:
+https://source.denx.de/Xenomai/xenomai/-/commit/627d488db3aa71406e32d4d8934629e8b0f35905]
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
+---
+ include/copperplate/threadobj.h | 6 +++++-
+ lib/cobalt/printf.c             | 2 +-
+ 2 files changed, 6 insertions(+), 2 deletions(-)
+
+diff --git a/include/copperplate/threadobj.h b/include/copperplate/threadobj.h
+index 7e6904f4c..c8363415b 100644
+--- a/include/copperplate/threadobj.h
++++ b/include/copperplate/threadobj.h
+@@ -173,7 +173,11 @@ void threadobj_save_timeout(struct threadobj_corespec *corespec,
+ #define __THREAD_M_SPARE6	(1 << 22)
+ #define __THREAD_M_SPARE7	(1 << 23)
+ 
+-#define THREADOBJ_IRQCONTEXT    ((struct threadobj *)-2UL)
++/*
++ * We need to use a valid address here. The object will never be dereferenced
++ * when it is identified as IRQ context, so the pthread key itself is fine.
++ */
++#define THREADOBJ_IRQCONTEXT	((struct threadobj *)&threadobj_tskey)
+ 
+ struct traceobj;
+ struct syncobj;
+diff --git a/lib/cobalt/printf.c b/lib/cobalt/printf.c
+index 8982ddc93..0aa5940c6 100644
+--- a/lib/cobalt/printf.c
++++ b/lib/cobalt/printf.c
+@@ -729,7 +729,7 @@ done:
+ 	pthread_cond_init(&printer_wakeup, NULL);
+ 	spawn_printer_thread();
+ 	/* We just need a non-zero TSD to trigger the dtor upon unwinding. */
+-	pthread_setspecific(cleanup_key, (void *)1);
++	pthread_setspecific(cleanup_key, &cleanup_key);
+ 
+ 	atexit(rt_print_flush_buffers);
+ }
+-- 
+GitLab
+
-- 
2.33.0