diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/auto-regress/bug778557.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/auto-regress/bug778557.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,7 @@
+// Binary: cache/js-dbg-64-90828ac18dcf-linux
+// Flags:
+//
+x = Set;
+eval("function y()(Iterator)", this);
+x.__iterator__ = y;
+new Iterator(x)