diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_5/extensions/regress-488995.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_5/extensions/regress-488995.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,46 @@
+/* -*- 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 = 488995;
+var summary = 'Do not crash with watch, __defineSetter__ on svg';
+var actual = '';
+var expect = '';
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+
+  if (typeof document == 'undefined')
+  {
+    print('Test skipped: requires browser.');
+  }
+  else
+  {
+    try
+    {
+      var o=document.createElementNS("http://www.w3.org/2000/svg", "svg");
+      var p=o.y;
+      p.watch('animVal', function(id, oldvar, newval) {} );
+      p.type='xxx';
+      p.__defineSetter__('animVal', function() {});
+      p.animVal=0;
+    }
+    catch(ex)
+    {
+    }
+  }
+
+  reportCompare(expect, actual, summary);
+
+  exitFunc ('test');
+}