diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/parallel/bailout-never-executed.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/parallel/bailout-never-executed.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,17 @@
+// |jit-test| slow;
+// ^^ This test is slow when --no-ion is used, specifically,
+//    as part of TBPL.
+
+load(libdir + "parallelarray-helpers.js");
+
+function makeObject(e, i, c) {
+  var v = {element: e, index: i, collection: c};
+
+  if (e == 512) // note: never happens
+    delete v.i;
+
+  return v;
+}
+
+if (getBuildConfiguration().parallelJS)
+  assertArraySeqParResultsEq(range(0, 512), "map", makeObject);