[PATCH] Fix sysrq/panic for gcc 3.1

[Andi Kleen]

Without this patch a loop checking for emergency_sync_scheduled in panic() is optimized
away by gcc 3.1, which causes hangs in panic.

-Andi

diff -X ../../KDIFX -x *-o -x *-RESERVE -burpN ../../v2.5/linux/drivers/char/sysrq.c linux/drivers/char/sysrq.c
--- ../../v2.5/linux/drivers/char/sysrq.c	Thu Mar 28 10:06:16 2002
+++ linux/drivers/char/sysrq.c	Fri Apr 12 18:32:46 2002
@@ -186,7 +186,7 @@ static void go_sync(struct super_block *
  * block devices and malfunctional network filesystems.
  */
 
-int emergency_sync_scheduled;
+volatile int emergency_sync_scheduled;
 
 void do_emergency_sync(void) {
 	struct super_block *sb;
diff -X ../../KDIFX -x *-o -x *-RESERVE -burpN ../../v2.5/linux/include/linux/sysrq.h linux/include/linux/sysrq.h
--- ../../v2.5/linux/include/linux/sysrq.h	Wed Apr 17 13:33:34 2002
+++ linux/include/linux/sysrq.h	Sat Apr 20 16:12:00 2002
@@ -103,7 +103,7 @@ static inline int __reterr(void)
 
 /* Deferred actions */
 
-extern int emergency_sync_scheduled;
+extern volatile int emergency_sync_scheduled;
 
 #define EMERG_SYNC 1
 #define EMERG_REMOUNT 2