diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_5/extensions/regress-375801.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_5/extensions/regress-375801.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//-----------------------------------------------------------------------------
+var BUGNUMBER = 375801;
+var summary = 'uneval should use "(void 0)" instead of "undefined"';
+var actual = '';
+var expect = '';
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+ 
+  expect = '({a: (void 0)})'
+  actual = uneval({a: undefined})
+  compareSource(expect, actual, summary + ': uneval');
+
+  expect = 'function() {({a: undefined});}';
+  actual = (function() {({a: undefined});}).toString();
+  compareSource(expect, actual, summary + ': toString');
+
+  expect = '(function () {({a: undefined});})';
+  actual = (function () {({a: undefined});}).toSource();
+  compareSource(expect, actual, summary + ': toSource');
+
+  exitFunc ('test');
+}