diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/testObjectToString.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/testObjectToString.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,8 @@
+function testObjectToString() {
+    var o = {toString: function()"foo"};
+    var s = "";
+    for (var i = 0; i < 10; i++)
+        s += o;
+    return s;
+}
+assertEq(testObjectToString(), "foofoofoofoofoofoofoofoofoofoo");