diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/testMethodWriteBarrier4.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/testMethodWriteBarrier4.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,12 @@
+var z = 0;
+function f() {
+    this.b = function() {};
+    this.b = undefined;
+    if (z++ > 8)
+        this.b();
+}
+
+try {
+    for (var i = 0; i < 10; i++)
+        new f();
+} catch (exc) {}