diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_7/geniter/regress-345855.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_7/geniter/regress-345855.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,93 @@
+/* -*- 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 = 345855;
+var summary = 'Blank yield expressions are not syntax errors';
+var actual = '';
+var expect = 'No Error';
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+ 
+  expect = "SyntaxError";
+  try
+  {
+    eval('(function() {x = 12 + yield;})');
+    actual = 'No Error';
+  }
+  catch(ex)
+  {
+    actual = ex.name;
+  }
+  reportCompare(expect, actual, summary + ': function() {x = 12 + yield;}');
+
+  expect = "SyntaxError";
+  try
+  {
+    eval('(function() {x = 12 + yield 42})');
+    actual = 'No Error';
+  }
+  catch(ex)
+  {
+    actual = ex.name;
+  }
+  reportCompare(expect, actual, summary + ': function() {x = 12 + yield 42}');
+
+  expect = 'No Error';
+  try
+  {
+    eval('(function() {x = 12 + (yield);})');
+    actual = 'No Error';
+  }
+  catch(ex)
+  {
+    actual = ex + '';
+  }
+  reportCompare(expect, actual, summary + ': function() {x = 12 + (yield);}');
+
+  try
+  {
+    eval('(function () {foo((yield))})');
+    actual = 'No Error';
+  }
+  catch(ex)
+  {
+    actual = ex + '';
+  }
+  reportCompare(expect, actual, summary + ': function () {foo((yield))}');
+
+  try
+  {
+    eval('(function() {x = 12 + (yield 42)})');
+    actual = 'No Error';
+  }
+  catch(ex)
+  {
+    actual = ex + '';
+  }
+  reportCompare(expect, actual, summary + ': function() {x = 12 + (yield 42)}');
+
+  try
+  {
+    eval('(function (){foo((yield 42))})');
+    actual = 'No Error';
+  }
+  catch(ex)
+  {
+    actual = ex + '';
+  }
+  reportCompare(expect, actual, summary + ': function (){foo((yield 42))}');
+
+  exitFunc ('test');
+}