diff --git a/jenkins-common.sh b/jenkins-common.sh
index 9fd3857e..01f23d01 100644
--- a/jenkins-common.sh
+++ b/jenkins-common.sh
@@ -3,6 +3,7 @@ docker_image_exists() {
 }
 
 docker_images_require() {
+	local i
 	local from_line
 	local pull_arg