diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug783590.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug783590.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,14 @@
+// |jit-test| error: TypeError
+
+var glob = this;
+var arr = [];
+Object.defineProperty(arr, 0, {
+  get: (function() {
+    glob.__proto__;
+  })
+});
+this.watch("s", function() {});
+try {
+  arr.pop();
+} catch (e) {}
+arr.pop();