diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/testBug579647.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/testBug579647.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,13 @@
+expected = "TypeError: a is not a function";
+actual = "";
+
+try {
+    a = ""
+    for each(x in [0, 0, 0, 0]) {
+        a %= x
+    } ( let (a=-a) a)()
+} catch (e) {
+    actual = '' + e;
+}
+
+assertEq(actual, expected);