diff --git a/lib/6to5/transformation/templates/to-array.js b/lib/6to5/transformation/templates/to-array.js
index c479b65446..820a6f06da 100644
--- a/lib/6to5/transformation/templates/to-array.js
+++ b/lib/6to5/transformation/templates/to-array.js
@@ -1,3 +1,9 @@
 (function (arr) {
-  return Array.isArray(arr) ? arr : Array.from(arr);
+  if (Array.isArray(arr)) {
+    var arr2 = [];
+    for (var i = 0; i < arr.length; i++) arr2.push(arr[i]);
+      return arr2;
+  } else {
+    return Array.from(arr);
+  }
 });
diff --git a/test/fixtures/transformation/es6-destructuring/spread/expected.js b/test/fixtures/transformation/es6-destructuring/spread/expected.js
index d7543faac6..b170df5f45 100644
--- a/test/fixtures/transformation/es6-destructuring/spread/expected.js
+++ b/test/fixtures/transformation/es6-destructuring/spread/expected.js
@@ -1,6 +1,6 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
 var isSorted = function (_ref) {
   var _ref2 = _toArray(_ref);
@@ -12,4 +12,4 @@ var isSorted = function (_ref) {
   if (!zs.length) return true;
   if (y > x) return isSorted(zs);
   return false;
-};
\ No newline at end of file
+};
diff --git a/test/fixtures/transformation/es6-spread/array-literal-first/expected.js b/test/fixtures/transformation/es6-spread/array-literal-first/expected.js
index 4f599ff941..9e6356e2ca 100644
--- a/test/fixtures/transformation/es6-spread/array-literal-first/expected.js
+++ b/test/fixtures/transformation/es6-spread/array-literal-first/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-var lyrics = [].concat(_toArray(parts), ["head", "and", "toes"]);
\ No newline at end of file
+var lyrics = [].concat(_toArray(parts), ["head", "and", "toes"]);
diff --git a/test/fixtures/transformation/es6-spread/array-literal-middle/expected.js b/test/fixtures/transformation/es6-spread/array-literal-middle/expected.js
index 74fb15b350..7c3bbd996a 100644
--- a/test/fixtures/transformation/es6-spread/array-literal-middle/expected.js
+++ b/test/fixtures/transformation/es6-spread/array-literal-middle/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-var a = [b].concat(_toArray(c), [d]);
\ No newline at end of file
+var a = [b].concat(_toArray(c), [d]);
diff --git a/test/fixtures/transformation/es6-spread/array-literal-multiple/expected.js b/test/fixtures/transformation/es6-spread/array-literal-multiple/expected.js
index 5ddf59335e..f3876c1bba 100644
--- a/test/fixtures/transformation/es6-spread/array-literal-multiple/expected.js
+++ b/test/fixtures/transformation/es6-spread/array-literal-multiple/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-var a = [b].concat(_toArray(c), [d, e], _toArray(f));
\ No newline at end of file
+var a = [b].concat(_toArray(c), [d, e], _toArray(f));
diff --git a/test/fixtures/transformation/es6-spread/array-literals/expected.js b/test/fixtures/transformation/es6-spread/array-literals/expected.js
index 754ab5115c..96cbadfada 100644
--- a/test/fixtures/transformation/es6-spread/array-literals/expected.js
+++ b/test/fixtures/transformation/es6-spread/array-literals/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-var lyrics = ["head", "and", "toes"].concat(_toArray(parts));
\ No newline at end of file
+var lyrics = ["head", "and", "toes"].concat(_toArray(parts));
diff --git a/test/fixtures/transformation/es6-spread/contexted-computed-method-call-multiple-args/expected.js b/test/fixtures/transformation/es6-spread/contexted-computed-method-call-multiple-args/expected.js
index fe2844f752..f107616b53 100644
--- a/test/fixtures/transformation/es6-spread/contexted-computed-method-call-multiple-args/expected.js
+++ b/test/fixtures/transformation/es6-spread/contexted-computed-method-call-multiple-args/expected.js
@@ -1,6 +1,6 @@
 "use strict";
 
 var _obj;
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-(_obj = obj)[method].apply(_obj, [foo, bar].concat(_toArray(args)));
\ No newline at end of file
+(_obj = obj)[method].apply(_obj, [foo, bar].concat(_toArray(args)));
diff --git a/test/fixtures/transformation/es6-spread/contexted-computed-method-call-single-arg/expected.js b/test/fixtures/transformation/es6-spread/contexted-computed-method-call-single-arg/expected.js
index f87fa8da5c..359469abac 100644
--- a/test/fixtures/transformation/es6-spread/contexted-computed-method-call-single-arg/expected.js
+++ b/test/fixtures/transformation/es6-spread/contexted-computed-method-call-single-arg/expected.js
@@ -1,6 +1,6 @@
 "use strict";
 
 var _obj;
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-(_obj = obj)[method].apply(_obj, _toArray(args));
\ No newline at end of file
+(_obj = obj)[method].apply(_obj, _toArray(args));
diff --git a/test/fixtures/transformation/es6-spread/contexted-method-call-multiple-args/expected.js b/test/fixtures/transformation/es6-spread/contexted-method-call-multiple-args/expected.js
index 5fc609a79c..e4f00193a6 100644
--- a/test/fixtures/transformation/es6-spread/contexted-method-call-multiple-args/expected.js
+++ b/test/fixtures/transformation/es6-spread/contexted-method-call-multiple-args/expected.js
@@ -1,7 +1,7 @@
 "use strict";
 
 var _foob, _foob$test;
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
 (_foob = foob).add.apply(_foob, [foo, bar].concat(_toArray(numbers)));
-(_foob$test = foob.test).add.apply(_foob$test, [foo, bar].concat(_toArray(numbers)));
\ No newline at end of file
+(_foob$test = foob.test).add.apply(_foob$test, [foo, bar].concat(_toArray(numbers)));
diff --git a/test/fixtures/transformation/es6-spread/contexted-method-call-single-arg/expected.js b/test/fixtures/transformation/es6-spread/contexted-method-call-single-arg/expected.js
index fe958b7719..0237ae9cea 100644
--- a/test/fixtures/transformation/es6-spread/contexted-method-call-single-arg/expected.js
+++ b/test/fixtures/transformation/es6-spread/contexted-method-call-single-arg/expected.js
@@ -1,7 +1,7 @@
 "use strict";
 
 var _foob, _foob$test;
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
 (_foob = foob).add.apply(_foob, _toArray(numbers));
-(_foob$test = foob.test).add.apply(_foob$test, _toArray(numbers));
\ No newline at end of file
+(_foob$test = foob.test).add.apply(_foob$test, _toArray(numbers));
diff --git a/test/fixtures/transformation/es6-spread/method-call-first/expected.js b/test/fixtures/transformation/es6-spread/method-call-first/expected.js
index ba8ad3b956..50acda90ed 100644
--- a/test/fixtures/transformation/es6-spread/method-call-first/expected.js
+++ b/test/fixtures/transformation/es6-spread/method-call-first/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-add.apply(undefined, _toArray(numbers).concat([foo, bar]));
\ No newline at end of file
+add.apply(undefined, _toArray(numbers).concat([foo, bar]));
diff --git a/test/fixtures/transformation/es6-spread/method-call-middle/expected.js b/test/fixtures/transformation/es6-spread/method-call-middle/expected.js
index d2a846d705..a2975e50c6 100644
--- a/test/fixtures/transformation/es6-spread/method-call-middle/expected.js
+++ b/test/fixtures/transformation/es6-spread/method-call-middle/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-add.apply(undefined, [foo].concat(_toArray(numbers), [bar]));
\ No newline at end of file
+add.apply(undefined, [foo].concat(_toArray(numbers), [bar]));
diff --git a/test/fixtures/transformation/es6-spread/method-call-multiple-args/expected.js b/test/fixtures/transformation/es6-spread/method-call-multiple-args/expected.js
index c256c920aa..3e0d49d9a3 100644
--- a/test/fixtures/transformation/es6-spread/method-call-multiple-args/expected.js
+++ b/test/fixtures/transformation/es6-spread/method-call-multiple-args/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-add.apply(undefined, [foo, bar].concat(_toArray(numbers)));
\ No newline at end of file
+add.apply(undefined, [foo, bar].concat(_toArray(numbers)));
diff --git a/test/fixtures/transformation/es6-spread/method-call-multiple/expected.js b/test/fixtures/transformation/es6-spread/method-call-multiple/expected.js
index 1ec67879ae..e57d5f4cc7 100644
--- a/test/fixtures/transformation/es6-spread/method-call-multiple/expected.js
+++ b/test/fixtures/transformation/es6-spread/method-call-multiple/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-add.apply(undefined, [foo].concat(_toArray(numbers), [bar, what], _toArray(test)));
\ No newline at end of file
+add.apply(undefined, [foo].concat(_toArray(numbers), [bar, what], _toArray(test)));
diff --git a/test/fixtures/transformation/es6-spread/method-call-single-arg/expected.js b/test/fixtures/transformation/es6-spread/method-call-single-arg/expected.js
index 374feff578..dad1dd21b6 100644
--- a/test/fixtures/transformation/es6-spread/method-call-single-arg/expected.js
+++ b/test/fixtures/transformation/es6-spread/method-call-single-arg/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-add.apply(undefined, _toArray(numbers));
\ No newline at end of file
+add.apply(undefined, _toArray(numbers));
diff --git a/test/fixtures/transformation/es6-spread/new-expression/expected.js b/test/fixtures/transformation/es6-spread/new-expression/expected.js
index b421806bf8..10889ab673 100644
--- a/test/fixtures/transformation/es6-spread/new-expression/expected.js
+++ b/test/fixtures/transformation/es6-spread/new-expression/expected.js
@@ -2,7 +2,7 @@
 
 var _applyConstructor = function (Constructor, args) { var instance = Object.create(Constructor.prototype); var result = Constructor.apply(instance, args); return result != null && (typeof result == "object" || typeof result == "function") ? result : instance; };
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
 _applyConstructor(Numbers, _toArray(nums));
-_applyConstructor(Numbers, [1].concat(_toArray(nums)));
\ No newline at end of file
+_applyConstructor(Numbers, [1].concat(_toArray(nums)));
diff --git a/test/fixtures/transformation/es6-spread/single/expected.js b/test/fixtures/transformation/es6-spread/single/expected.js
index 374e9cbd25..7005e8737a 100644
--- a/test/fixtures/transformation/es6-spread/single/expected.js
+++ b/test/fixtures/transformation/es6-spread/single/expected.js
@@ -1,5 +1,5 @@
 "use strict";
 
-var _toArray = function (arr) { return Array.isArray(arr) ? arr : Array.from(arr); };
+var _toArray = function (arr) { if (Array.isArray(arr)) { var arr2 = []; for (var i = 0; i < arr.length; i++) arr2.push(arr[i]); return arr2; } else { return Array.from(arr); } };
 
-[].concat(_toArray(foo));
\ No newline at end of file
+[].concat(_toArray(foo));