diff --git a/sys/conf/newvers.sh b/sys/conf/newvers.sh
index 6fe0a639a54..9681c7904d4 100644
--- a/sys/conf/newvers.sh
+++ b/sys/conf/newvers.sh
@@ -139,4 +139,4 @@ int osreldate = ${RELDATE};
 char kern_ident[] = "${i}";
 EOF
 
-echo `expr ${v} + 1` > version
+echo $((v + 1)) > version