diff --git a/lib/checksum.c b/lib/checksum.c
index 6a29cba..8c0ea52 100644
--- a/lib/checksum.c
+++ b/lib/checksum.c
@@ -9,9 +9,7 @@
 #include <zebra.h>
 
 int				/* return checksum in low-order 16 bits */
-in_cksum(ptr, nbytes)
-register u_short	*ptr;
-register int		nbytes;
+in_cksum(u_short *ptr, int nbytes)
 {
 	register long		sum;		/* assumes long == 32 bits */
 	u_short			oddbyte;