diff --git a/edksetup.sh b/edksetup.sh
index 752e47e7cb56..76c8d7916e31 100755
--- a/edksetup.sh
+++ b/edksetup.sh
@@ -199,7 +199,7 @@ do
       break
     ;;
   esac
-  I=$(($I - 1))
+  I=$((I - 1))
 done
 
 if [ $I -gt 0 ]