diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_7/extensions/regress-476257.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_7/extensions/regress-476257.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,59 @@
+// |reftest| skip-if(Android)
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//-----------------------------------------------------------------------------
+var BUGNUMBER = 476257;
+var summary = 'Do not assert: !JS_ON_TRACE(cx)';
+var actual = '';
+var expect = '';
+
+printBugNumber(BUGNUMBER);
+printStatus (summary);
+ 
+jit(true);
+
+function f1() {
+  try
+  {
+    Object.defineProperty(__proto__, "functional",
+    {
+      enumerable: true, configurable: true,
+      get: function ()
+      {
+        if (typeof gczeal == 'function') { gczeal(0); }
+      }
+    });
+    for each (let [[]] in [true, new Boolean(true), new Boolean(true)]) {}
+  }
+  catch(ex)
+  {
+  }
+}
+
+function f2() {
+  try
+  {
+    Object.defineProperty(__proto__, "functional",
+    {
+      enumerable: true, configurable: true,
+      get: function () 
+      { 
+        if (typeof dis == 'function') { dis(); } 
+      }
+    });
+    for each (let [[]] in [true, new Boolean(true), new Boolean(true)]) {}
+  }
+  catch(ex)
+  {
+  }
+}
+
+f1();
+f2();
+
+jit(false);
+
+reportCompare(expect, actual, summary);