diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/bug579740.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/bug579740.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,7 @@
+try {
+    for (a = 0; a < 4; a++) {
+        new Math.round(0).t
+    }
+}
+catch (e) {}
+/* Don't assert. */