diff -r 000000000000 -r 6474c204b198 js/src/tests/ecma_5/RegExp/exec-lastIndex-ToInteger.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/ecma_5/RegExp/exec-lastIndex-ToInteger.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,36 @@
+/*
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/
+ *
+ * Author: Geoffrey Sneddon <geoffers+mozilla@gmail.com>
+ */
+
+var BUGNUMBER = 646490;
+var summary =
+  "RegExp.prototype.exec doesn't get the lastIndex and ToInteger() it for " +
+  "non-global regular expressions when it should";
+
+print(BUGNUMBER + ": " + summary);
+
+/**************
+ * BEGIN TEST *
+ **************/
+
+var re = /./, called = 0;
+re.lastIndex = {valueOf: function() { called++; return 0; }};
+re.exec(".");
+re.lastIndex = {toString: function() { called++; return "0"; }};
+re.exec(".");
+re.lastIndex = {
+  valueOf: function() { called++; return 0; },
+  toString: function() { called--; }
+};
+re.exec(".");
+assertEq(called, 3, "FAIL, got " + called);
+
+/******************************************************************************/
+
+if (typeof reportCompare === "function")
+  reportCompare(true, true);
+
+print("All tests passed!");