diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/arguments/testDelArg3.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/arguments/testDelArg3.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,42 @@
+function assertGood(x) {
+    assertEq(x, "good");
+}
+
+(function() {
+    var a = arguments;
+    return function() {
+        assertGood.apply(null, a);
+    }
+})("good")();
+
+(function() {
+    var a = arguments;
+    return function() {
+        a[0] = "good";
+        assertGood.apply(null, a);
+    }
+})("bad")();
+
+Object.prototype[0] = "good";
+
+(function() {
+    var a = arguments;
+    return function() {
+        delete a[0];
+        assertGood.apply(null, a);
+    }
+})("bad")();
+
+delete Object.prototype[0];
+
+function assertUndefined(x) {
+    assertEq(x, undefined);
+}
+
+(function() {
+    var a = arguments;
+    return function() {
+        a[0] = "bad";
+        assertUndefined.apply(null, a);
+    }
+})()();