diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/bug621022-1.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/bug621022-1.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,14 @@
+function f(x) {
+    delete arguments[0];
+    undefined != arguments[0];
+    undefined == arguments[0];
+    undefined != arguments[0];
+    undefined === arguments[0];
+}
+
+for(var i=0; i<20; i++) {
+    f(1);
+}
+
+// Don't assert.
+