diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/testBug579602.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/testBug579602.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,21 @@
+// don't panic
+
+f = function() {
+  x = yield
+}
+rv = f()
+for (a in rv) (function() {})
+x = Proxy.create((function() {
+  return {
+    defineProperty: gc
+  }
+})(), x)
+with({
+  d: (({
+    x: Object.defineProperty(x, "", ({
+      set: Array.e
+    }))
+  }))
+}) {}
+
+// don't crash