x86: always define BUG() and HAVE_ARCH_BUG, even with !CONFIG_BUG

This ensures that BUG() always has a definition that causes a trap (via
an undefined instruction), and that the compiler still recognizes the
code following BUG() as unreachable, avoiding warnings that would
otherwise appear (such as on non-void functions that don't return a
value after BUG()).

In addition to saving a few bytes over the generic infinite-loop
implementation, this implementation traps rather than looping, which
potentially allows for better error-recovery behavior (such as by
rebooting).

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Josh Triplett 2014-04-07 15:39:14 -07:00 committed by Linus Torvalds
parent a4b5d580e0
commit b06dd879f5

View File

@ -1,7 +1,6 @@
#ifndef _ASM_X86_BUG_H
#define _ASM_X86_BUG_H
#ifdef CONFIG_BUG
#define HAVE_ARCH_BUG
#ifdef CONFIG_DEBUG_BUGVERBOSE
@ -33,8 +32,6 @@ do { \
} while (0)
#endif
#endif /* !CONFIG_BUG */
#include <asm-generic/bug.h>
#endif /* _ASM_X86_BUG_H */