diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/bug665289.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/bug665289.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,4 @@
+delete this.Function;
+a = evalcx("lazy");
+a["Object"] = this;
+if (typeof a.isPrototypeOf == "") {}