diff --git a/lib/6to5/transformation/templates/to-consumable-array.js b/lib/6to5/transformation/templates/to-consumable-array.js
index 820a6f06da..eae69c01a8 100644
--- a/lib/6to5/transformation/templates/to-consumable-array.js
+++ b/lib/6to5/transformation/templates/to-consumable-array.js
@@ -1,8 +1,7 @@
 (function (arr) {
   if (Array.isArray(arr)) {
-    var arr2 = [];
-    for (var i = 0; i < arr.length; i++) arr2.push(arr[i]);
-      return arr2;
+    for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) arr2.push(arr[i]);
+    return arr2;
   } else {
     return Array.from(arr);
   }