diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug878444.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug878444.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,26 @@
+function g()
+{
+    function f(v) {
+        v = +v;
+        var infinity = 0.0;
+        var three = 0.0;
+        var nan = 0.;
+        var result = 0;
+
+        infinity = 1.0 / 0.0;
+        three = v + 2.0;
+        nan = (infinity % three);
+        result = ~~(nan + 42.0);
+
+        return result | 0;
+    }
+    return f
+}
+
+g = g()
+var x;
+for(i=0; i < 20000; ++i)
+{
+    x = g(1.0)
+}
+assertEq(x, 0);