--- a/xpcom/threads/nsThreadPool.cpp
+++ b/xpcom/threads/nsThreadPool.cpp
@@ -1,22 +1,24 @@
 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
 /* 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/. */
 
+#include "nsCOMArray.h"
 #include "nsIClassInfoImpl.h"
 #include "nsThreadPool.h"
 #include "nsThreadManager.h"
 #include "nsThread.h"
 #include "nsMemory.h"
 #include "nsAutoPtr.h"
 #include "prinrval.h"
 #include "mozilla/Logging.h"
+#include "mozilla/SystemGroup.h"
 #include "nsThreadSyncDispatch.h"
 
 using namespace mozilla;
 
 static LazyLogModule sThreadPoolLog("nsThreadPool");
 #ifdef LOG
 #undef LOG
 #endif