[PATCH] BUG(): CONFIG_BUG=n version of BUG() should be unreachable()

From: Alexander Beregalov
Date: Tue Dec 22 2009 - 20:17:26 EST


Previouss definition of BUG() as 'do {} while(0)' produced compilation
warnings when BUG() was used in default branch of switch() statement
(control reaches end of non-void function).

Example:
unsigned long function()
{
switch() {
case 1:
return 1;
case 2:
return 2;
default:
BUG();
}

Using unreachable() fixes the problem.

Signed-off-by: Alexander Beregalov <a.beregalov@xxxxxxxxx>

diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
index 18c435d..1106439 100644
--- a/include/asm-generic/bug.h
+++ b/include/asm-generic/bug.h
@@ -89,7 +89,7 @@ extern void warn_slowpath_null(const char *file, const int line);

#else /* !CONFIG_BUG */
#ifndef HAVE_ARCH_BUG
-#define BUG() do {} while(0)
+#define BUG() unreachable()
#endif

#ifndef HAVE_ARCH_BUG_ON
--
1.6.6.rc4

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