Index: kernel/generic/include/typedefs.h
===================================================================
--- kernel/generic/include/typedefs.h	(revision 14795627234b341479d2a8da2a14117d97de69cc)
+++ kernel/generic/include/typedefs.h	(revision c63e70c6c7205da6494a4bd4241b669eb98c4c5f)
@@ -40,5 +40,5 @@
 #include <arch/types.h>
 
-#define NULL  0
+#define NULL  0UL
 
 #define false  0