diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug850099.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug850099.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,4 @@
+var buf = serialize(-1);
+var nbuf = serialize(undefined);
+for (var j = 0 ; j < 5; j++)
+    buf[j + 8] = nbuf[j];