[lkml]   [2012]   [Mar]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] do not export kernel's NULL #define to userspace
GCC's NULL is actually __null, which allows detecting some questionable
NULL usage and warn about it. Moreover each platform/compiler should have
its own stddef.h anyway (which is different from linux/stddef.h).
So there's no good reason to leak kernel's NULL to userspace and
override what the compiler provides.

Signed-off-by: Luboš Luňák <>
include/linux/stddef.h | 8 ++------
1 files changed, 2 insertions(+), 6 deletions(-)
diff --git a/include/linux/stddef.h b/include/linux/stddef.h
index 6a40c76..1747b67 100644
--- a/include/linux/stddef.h
+++ b/include/linux/stddef.h
@@ -3,14 +3,10 @@

#include <linux/compiler.h>

+#ifdef __KERNEL__
#undef NULL
-#if defined(__cplusplus)
-#define NULL 0
#define NULL ((void *)0)
-#ifdef __KERNEL__

enum {
false = 0,
Lubos Lunak
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at
 \ /
  Last update: 2012-03-21 14:11    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean