diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/bug623863.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/bug623863.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,5 @@
+// Contributor: Christian Holler <decoder@own-hero.net>
+if (typeof gczeal === 'function') gczeal(2);
+Function.prototype.prototype = function() { return 42; };
+try { foo(Function); } catch (e) { }
+Function.prototype.prototype = function() { return 42; };