Index: generic/include/adt/bitmap.h
===================================================================
--- generic/include/adt/bitmap.h	(revision 040e4e960e3a23fb69c3cf9e7c8ae7112d7bf526)
+++ generic/include/adt/bitmap.h	(revision a98cdc75925619cf46177b7e734930398d02a8e2)
@@ -33,5 +33,5 @@
 #include <typedefs.h>
 
-#define BITS2BYTES(bits)	((((bits)-1)>>3)+1)
+#define BITS2BYTES(bits)	(bits ? ((((bits)-1)>>3)+1) : 0)
 
 typedef struct {