diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/testBug659577-2.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/testBug659577-2.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,15 @@
+gczeal(4);
+evaluate("\
+Date.formatFunctions = {count:0};\
+Date.prototype.dateFormat = function(format) {\
+    var funcName = 'format' + Date.formatFunctions.count++;\
+    var code = 'Date.prototype.' + funcName + ' = function(){return ';\
+    var ch = '';\
+    for (var i = 0; i < format.length; ++i) {\
+        ch = format.charAt(i);\
+        eval(code.substring(0, code.length - 3) + ';}');\
+    }\
+};\
+var date = new Date('1/1/2007 1:11:11');\
+    var shortFormat = date.dateFormat('Y-m-d');\
+");