1 files changed, 9 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/basic/bug642894.js b/js/src/jit-test/tests/basic/bug642894.js
new file mode 100644
index 0000000000..5de6f3597e
--- /dev/null
+++ b/js/src/jit-test/tests/basic/bug642894.js
@@ -0,0 +1,9 @@
+
+function foo() {
+  var x = {};
+  x.__proto__ = function() { return 0 }
+  return x;
+}
+var a = foo();
+var b = foo();
+assertEq(a.__proto__ === b.__proto__, false);