diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/parallel/bug853576.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/parallel/bug853576.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,8 @@
+// |jit-test| error: Error;
+
+var len = 2;
+function add1(x) { return x+1; }
+var p = new ParallelArray(len, add1);
+var idx = [0,0].concat(build(len-4, add1)).concat([len-3,len-3]);
+var revidx = idx.reverse();
+var r = p.scatter(revidx, 0, function (x,y) { return x+y; }, len-2, {});