diff --git a/doc/scripts/subst.sh b/doc/scripts/subst.sh
index 87e79c8..281a96b 100755
--- a/doc/scripts/subst.sh
+++ b/doc/scripts/subst.sh
@@ -179,6 +179,6 @@ while [ $# -gt 0 ]; do
 		$RM -- "$target" 2> "$DEVNULL"
 		exit 2
 	elif [ -x "$source" ]; then
-		$DEBUG $CHMOD 0755 "$target"
+		$DEBUG $CHMOD -- 0755 "$target"
 	fi
 done