[PATCH] NULL: define as a null pointer

[Du Huanpeng]

From: Du Huanpeng <u74147 at gmail.com>

ISO/IEC 9899:TC3 says:
The macros are
	NULL
which expands to an implementation-defined null pointer constant;

Signed-off-by: Du Huanpeng <u74147 at gmail.com>
---
 include/command.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/command.h b/include/command.h
index 3aca1a9..e41068a 100644
--- a/include/command.h
+++ b/include/command.h
@@ -27,7 +27,7 @@
 #include <linux/stringify.h>
 
 #ifndef NULL
-#define NULL	0
+#define NULL	((void *)0)
 #endif
 
 #ifndef	__ASSEMBLY__
-- 
1.9.1