diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/non-extensible-array.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/non-extensible-array.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,7 @@
+
+function foo(x) {
+  Object.seal(x);
+  x[3] = 4;
+  assertEq("" + x, "1,2,3");
+}
+foo([1,2,3]);