diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_5/Regress/regress-419018.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_5/Regress/regress-419018.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,47 @@
+/* -*- 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 = 419018;
+var summary = 'UMR in JSENUMERATE_INIT';
+var actual = 'No Crash';
+var expect = 'No Crash';
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+
+  print('This test must be run under valgrind to check if an UMR occurs in slowarray_enumerate');
+
+  try
+  {
+    function parse() {
+      var a = []; // need array init
+      a["b"] = 1; // need to set obj property
+      return a;
+    }
+    // var c; // can't declare c
+    // var d = {}; // can't add this (weird!)
+    // var d = ""; // nor this
+    var x = parse(""); // won't crash without string arg (weird!)
+    // var d = ""; // nor here
+    for (var o in x)
+      c[o]; // need to look up o in undefined object
+  }
+  catch(ex)
+  {
+  }
+
+  reportCompare(expect, actual, summary);
+
+  exitFunc ('test');
+}
+