diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/baseline/bug847484.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/baseline/bug847484.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,14 @@
+function TestCase(n, d) {}
+function reportCompare() {
+    new TestCase;
+}
+Object.defineProperty(Object.prototype, "name", {});
+reportCompare();
+try {
+    function TestCase( n, d ) {
+	this.name = n;
+	this.description = d;
+    }
+    reportCompare();
+    reportCompare();
+} catch(exc3) { assertEq(0, 1); }