diff --git a/src/drivers/device/device.h b/src/drivers/device/device.h
index 7df234cab0..2d105bb791 100644
--- a/src/drivers/device/device.h
+++ b/src/drivers/device/device.h
@@ -240,6 +240,7 @@ private:
 	 * @param context	Pointer to the interrupted context.
 	 */
 	static void	dev_interrupt(int irq, void *context);
+
 };
 
 /**
@@ -469,6 +470,10 @@ private:
 	 * @return		OK, or -errno on error.
 	 */
 	int		remove_poll_waiter(struct pollfd *fds);
+
+	/* do not allow copying this class */
+	CDev(const CDev&);
+	CDev operator=(const CDev&);
 };
 
 /**
diff --git a/src/modules/mavlink/mavlink_commands.cpp b/src/modules/mavlink/mavlink_commands.cpp
index fccd4d9a59..b502c3c863 100644
--- a/src/modules/mavlink/mavlink_commands.cpp
+++ b/src/modules/mavlink/mavlink_commands.cpp
@@ -40,9 +40,12 @@
 
 #include "mavlink_commands.h"
 
-MavlinkCommandsStream::MavlinkCommandsStream(Mavlink *mavlink, mavlink_channel_t channel) : _channel(channel), _cmd_time(0)
+MavlinkCommandsStream::MavlinkCommandsStream(Mavlink *mavlink, mavlink_channel_t channel) :
+	_cmd_sub(mavlink->add_orb_subscription(ORB_ID(vehicle_command))),
+	_cmd{},
+	_channel(channel),
+	_cmd_time(0)
 {
-	_cmd_sub = mavlink->add_orb_subscription(ORB_ID(vehicle_command));
 }
 
 void
diff --git a/src/modules/mavlink/mavlink_ftp.cpp b/src/modules/mavlink/mavlink_ftp.cpp
index 675a6870e1..6a2c900afe 100644
--- a/src/modules/mavlink/mavlink_ftp.cpp
+++ b/src/modules/mavlink/mavlink_ftp.cpp
@@ -50,16 +50,20 @@ MavlinkFTP::getServer()
 	return _server;
 }
 
-MavlinkFTP::MavlinkFTP()
+MavlinkFTP::MavlinkFTP() :
+	_session_fds{},
+	_workBufs{},
+	_workFree{},
+	_lock{}
 {
 	// initialise the request freelist
 	dq_init(&_workFree);
 	sem_init(&_lock, 0, 1);
-    
-    // initialize session list
-    for (size_t i=0; i<kMaxSession; i++) {
-        _session_fds[i] = -1;
-    }
+
+	// initialize session list
+	for (size_t i=0; i<kMaxSession; i++) {
+		_session_fds[i] = -1;
+	}
 
 	// drop work entries onto the free list
 	for (unsigned i = 0; i < kRequestQueueSize; i++) {
diff --git a/src/modules/mavlink/mavlink_main.cpp b/src/modules/mavlink/mavlink_main.cpp
index cd0581af43..76b5459a3e 100644
--- a/src/modules/mavlink/mavlink_main.cpp
+++ b/src/modules/mavlink/mavlink_main.cpp
@@ -216,6 +216,7 @@ Mavlink::Mavlink() :
 	_device_name(DEFAULT_DEVICE_NAME),
 	_task_should_exit(false),
 	next(nullptr),
+	_instance_id(0),
 	_mavlink_fd(-1),
 	_task_running(false),
 	_hil_enabled(false),
@@ -230,17 +231,24 @@ Mavlink::Mavlink() :
 	_mission_pub(-1),
 	_mission_result_sub(-1),
 	_mode(MAVLINK_MODE_NORMAL),
+	_channel(MAVLINK_COMM_0),
+	_logbuffer{},
 	_total_counter(0),
+	_receive_thread{},
 	_verbose(false),
 	_forwarding_on(false),
 	_passing_on(false),
 	_ftp_on(false),
 	_uart_fd(-1),
+	_baudrate(57600),
+	_datarate(10000),
 	_mavlink_param_queue_index(0),
+	mavlink_link_termination_allowed(false),
 	_subscribe_to_stream(nullptr),
 	_subscribe_to_stream_rate(0.0f),
 	_flow_control_enabled(true),
-	_message_buffer({}),
+	_message_buffer{},
+	_message_buffer_mutex{},
 	_param_initialized(false),
 	_param_system_id(0),
 	_param_component_id(0),
diff --git a/src/modules/mavlink/mavlink_main.h b/src/modules/mavlink/mavlink_main.h
index acfc8b90eb..da989d6c51 100644
--- a/src/modules/mavlink/mavlink_main.h
+++ b/src/modules/mavlink/mavlink_main.h
@@ -372,4 +372,8 @@ private:
 	 * Main mavlink task.
 	 */
 	int		task_main(int argc, char *argv[]);
+
+	/* do not allow copying this class */
+	Mavlink(const Mavlink&);
+	Mavlink operator=(const Mavlink&);
 };
diff --git a/src/modules/mavlink/mavlink_mission.h b/src/modules/mavlink/mavlink_mission.h
index f63c32f243..b792b9aaf9 100644
--- a/src/modules/mavlink/mavlink_mission.h
+++ b/src/modules/mavlink/mavlink_mission.h
@@ -174,4 +174,8 @@ private:
 
 	mavlink_channel_t	_channel;
 	uint8_t			_comp_id;
+
+	/* do not allow copying this class */
+	MavlinkMissionManager(const MavlinkMissionManager&);
+	MavlinkMissionManager operator=(const MavlinkMissionManager&);
 };
diff --git a/src/modules/mavlink/mavlink_orb_subscription.h b/src/modules/mavlink/mavlink_orb_subscription.h
index 71efb43af0..7af454df65 100644
--- a/src/modules/mavlink/mavlink_orb_subscription.h
+++ b/src/modules/mavlink/mavlink_orb_subscription.h
@@ -82,6 +82,10 @@ private:
 	const orb_id_t _topic;		///< topic metadata
 	int _fd;			///< subscription handle
 	bool _published;		///< topic was ever published
+
+	/* do not allow copying this class */
+	MavlinkOrbSubscription(const MavlinkOrbSubscription&);
+	MavlinkOrbSubscription operator=(const MavlinkOrbSubscription&);
 };
 
 
diff --git a/src/modules/mavlink/mavlink_receiver.cpp b/src/modules/mavlink/mavlink_receiver.cpp
index 99ec98ee9c..4740f674dc 100644
--- a/src/modules/mavlink/mavlink_receiver.cpp
+++ b/src/modules/mavlink/mavlink_receiver.cpp
@@ -86,7 +86,9 @@ static const float mg2ms2 = CONSTANTS_ONE_G / 1000.0f;
 
 MavlinkReceiver::MavlinkReceiver(Mavlink *parent) :
 	_mavlink(parent),
-
+	status{},
+	hil_local_pos{},
+	_control_mode{},
 	_global_pos_pub(-1),
 	_local_pos_pub(-1),
 	_attitude_pub(-1),
@@ -111,15 +113,13 @@ MavlinkReceiver::MavlinkReceiver(Mavlink *parent) :
 	_manual_pub(-1),
 	_telemetry_heartbeat_time(0),
 	_radio_status_available(false),
-	_control_mode_sub(-1),
+	_control_mode_sub(orb_subscribe(ORB_ID(vehicle_control_mode))),
 	_hil_frames(0),
 	_old_timestamp(0),
 	_hil_local_proj_inited(0),
-	_hil_local_alt0(0.0)
+	_hil_local_alt0(0.0f),
+	_hil_local_proj_ref{}
 {
-	_control_mode_sub = orb_subscribe(ORB_ID(vehicle_control_mode));
-	memset(&hil_local_pos, 0, sizeof(hil_local_pos));
-	memset(&_control_mode, 0, sizeof(_control_mode));
 
 	// make sure the FTP server is started
 	(void)MavlinkFTP::getServer();
diff --git a/src/modules/mavlink/mavlink_receiver.h b/src/modules/mavlink/mavlink_receiver.h
index 8d38b9973f..b64a060e3a 100644
--- a/src/modules/mavlink/mavlink_receiver.h
+++ b/src/modules/mavlink/mavlink_receiver.h
@@ -156,4 +156,8 @@ private:
 	bool _hil_local_proj_inited;
 	float _hil_local_alt0;
 	struct map_projection_reference_s _hil_local_proj_ref;
+
+	/* do not allow copying this class */
+	MavlinkReceiver(const MavlinkReceiver&);
+	MavlinkReceiver operator=(const MavlinkReceiver&);
 };
diff --git a/src/modules/mavlink/mavlink_stream.h b/src/modules/mavlink/mavlink_stream.h
index 69809a3869..20e1c7c449 100644
--- a/src/modules/mavlink/mavlink_stream.h
+++ b/src/modules/mavlink/mavlink_stream.h
@@ -77,6 +77,10 @@ protected:
 
 private:
 	hrt_abstime _last_sent;
+
+	/* do not allow top copying this class */
+	MavlinkStream(const MavlinkStream&);
+	MavlinkStream& operator=(const MavlinkStream&);
 };
 
 
diff --git a/src/modules/mavlink/module.mk b/src/modules/mavlink/module.mk
index d49bbb7f7d..1986ae3c8f 100644
--- a/src/modules/mavlink/module.mk
+++ b/src/modules/mavlink/module.mk
@@ -52,3 +52,5 @@ INCLUDE_DIRS	 += $(MAVLINK_SRC)/include/mavlink
 MAXOPTIMIZATION	 = -Os
 
 MODULE_STACKSIZE = 1024
+
+EXTRACXXFLAGS	= -Weffc++