diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug798946.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug798946.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,16 @@
+// Don't assert with --ion-eager.
+function RandBool() { var x = Math.random() >= 0.5; return x; }
+var CHARS = "aaa";
+function RandStr() {
+  var c = Math.floor(Math.random() * CHARS.length);
+}
+function RandVal() { 
+  return RandBool() ? RandStr() : RandStr(); 
+}
+function GenerateSpecPermutes(matchVals, resultArray) {
+    var maxPermuteBody = (1 << matchVals.length) - 1;
+    for(var bod_pm = 0; bod_pm <= maxPermuteBody; bod_pm++)
+      for(var k = 0; k < matchVals.length; k++)
+        var body = ((bod_pm & (1 << k)) > 0) ? null : RandVal();
+}
+GenerateSpecPermutes(["foo", "bar", "zing"]);