fix warnings

include/libtorrent/alert_types.hpp

@@ -2174,7 +2174,7 @@ namespace libtorrent
 			outgoing_message,
 			incoming,
 			outgoing,
-			info,
+			info
 		};
 
 		// internal

include/libtorrent/performance_counters.hpp

@@ -308,7 +308,7 @@ namespace libtorrent
 			socket_recv_size19,
 			socket_recv_size20,
 
-			num_stats_counters,
+			num_stats_counters
 		};
 
 		// == ALL FOLLOWING ARE GAUGES ==

include/libtorrent/tracker_manager.hpp

@@ -338,7 +338,7 @@ namespace libtorrent
 			, aux::session_logger& ses
 #endif
 			);
-		~tracker_manager();
+		virtual ~tracker_manager();
 
 		void queue_request(
 			io_service& ios
@@ -355,12 +355,12 @@ namespace libtorrent
 		void received_bytes(int bytes);
 
 		virtual bool incoming_packet(error_code const& e, udp::endpoint const& ep
-			, char const* buf, int size);
+			, char const* buf, int size) TORRENT_OVERRIDE;
 
 		// this is only used for SOCKS packets, since
 		// they may be addressed to hostname
 		virtual bool incoming_packet(error_code const& e, char const* hostname
-			, char const* buf, int size);
+			, char const* buf, int size) TORRENT_OVERRIDE;
 
 		void update_transaction_id(
 			boost::shared_ptr<udp_tracker_connection> c