diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/bug646968-3.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/bug646968-3.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,16 @@
+var s, x = 0;
+
+s = '';
+for (let x = x; x < 3; x++)
+    s += x;
+assertEq(s, '012');
+
+s = '';
+for (let x = eval('x'); x < 3; x++)
+    s += x;
+assertEq(s, '012');
+
+s = ''
+for (let x = function () { with ({}) return x; }(); x < 3; x++)
+    s += x;
+assertEq(s, '012');