diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/testHolePushing.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/testHolePushing.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,13 @@
+function testHolePushing() {
+    var a = ["foobar", "baz"];
+    for (var i = 0; i < 5; i++)
+        a = [, "overwritten", "new"];
+    var s = "[";
+    for (i = 0; i < a.length; i++) {
+        s += (i in a) ? a[i] : "<hole>";
+        if (i != a.length - 1)
+            s += ",";
+    }
+    return s + "], " + (0 in a);
+}
+assertEq(testHolePushing(), "[<hole>,overwritten,new], false");