diff --git a/lib/cpp/src/thrift/concurrency/ThreadManager.h b/lib/cpp/src/thrift/concurrency/ThreadManager.h
index de45d56..0fedc88 100644
--- a/lib/cpp/src/thrift/concurrency/ThreadManager.h
+++ b/lib/cpp/src/thrift/concurrency/ThreadManager.h
@@ -57,7 +57,6 @@
   ThreadManager() {}
 
  public:
-  class Task;
   typedef apache::thrift::stdcxx::function<void(boost::shared_ptr<Runnable>)> ExpireCallback;
 
   virtual ~ThreadManager() {}