AP_GPS: fixed uninitialied variable bugs found with valgrind

libraries/AP_GPS/AP_GPS_406.cpp

@@ -24,8 +24,6 @@ void AP_GPS_406::init(AP_HAL::UARTDriver *s, enum GPS_Engine_Setting nav_setting
     _configure_gps();                           // Function to configure GPS, to output only the desired msg's
 
     AP_GPS_SIRF::init(s, nav_setting);                     // let the superclass do anything it might need here
-
-    idleTimeout = 1200;
 }
 
 // Private Methods //////////////////////////////////////////////////////////////

libraries/AP_GPS/AP_GPS_Auto.cpp

@@ -28,7 +28,6 @@ void
 AP_GPS_Auto::init(AP_HAL::UARTDriver *s, enum GPS_Engine_Setting nav_setting)
 {
 	_port = s;
-    idleTimeout = 1200;
     _nav_setting = nav_setting;
 }
 

libraries/AP_GPS/AP_GPS_HIL.cpp

@@ -18,7 +18,6 @@
 void AP_GPS_HIL::init(AP_HAL::UARTDriver *s, enum GPS_Engine_Setting nav_setting)
 {
 	_port = s;
-    idleTimeout = 1200;
 }
 
 bool AP_GPS_HIL::read(void)

libraries/AP_GPS/AP_GPS_MTK.cpp

@@ -43,8 +43,6 @@ AP_GPS_MTK::init(AP_HAL::UARTDriver *s, enum GPS_Engine_Setting nav_setting)
 
     // set initial epoch code
     _epoch = TIME_OF_DAY;
-
-    idleTimeout = 1200;
 }
 
 // Process bytes available from the stream

libraries/AP_GPS/AP_GPS_MTK19.cpp

@@ -44,7 +44,6 @@ AP_GPS_MTK19::init(AP_HAL::UARTDriver *s, enum GPS_Engine_Setting nav_setting)
     _epoch = TIME_OF_DAY;
     _time_offset = 0;
     _offset_calculated = false;
-    idleTimeout = 1200;
 }
 
 // Process bytes available from the stream

libraries/AP_GPS/AP_GPS_NMEA.cpp

@@ -103,8 +103,6 @@ void AP_GPS_NMEA::init(AP_HAL::UARTDriver *s, enum GPS_Engine_Setting nav_settin
 
     // send the ublox init strings
     _port->print_P((const prog_char_t *)_ublox_init_string);
-
-    idleTimeout = 1200;
 }
 
 bool AP_GPS_NMEA::read(void)

libraries/AP_GPS/AP_GPS_SIRF.cpp

@@ -37,7 +37,6 @@ AP_GPS_SIRF::init(AP_HAL::UARTDriver *s, enum GPS_Engine_Setting nav_setting)
 
     // send SiRF binary setup messages
     _write_progstr_block(_port, (const prog_char *)init_messages, sizeof(init_messages));
-    idleTimeout = 1200;
 }
 
 // Process bytes available from the stream

libraries/AP_GPS/AP_GPS_UBLOX.cpp

@@ -44,7 +44,6 @@ AP_GPS_UBLOX::init(AP_HAL::UARTDriver *s, enum GPS_Engine_Setting nav_setting)
     _port->flush();
 
     _epoch = TIME_OF_WEEK;
-    idleTimeout = 1200;
 
     // configure the GPS for the messages we want
     _configure_gps();

libraries/AP_GPS/GPS.cpp

@@ -19,17 +19,19 @@ extern const AP_HAL::HAL& hal;
 
 GPS::GPS(void) :
 	// ensure all the inherited fields are zeroed
+	time(0),
 	num_sats(0),
 	new_data(false),
 	fix(FIX_NONE),
 	valid_read(false),
 	last_fix_time(0),
 	_have_raw_velocity(false),
+	_idleTimer(0),
 	_status(GPS::NO_FIX),
 	_last_ground_speed_cm(0),
 	_velocity_north(0),
 	_velocity_east(0),
-	_velocity_down(0)	
+	_velocity_down(0)
 {
 }
 
@@ -44,9 +46,9 @@ GPS::update(void)
 
     tnow = hal.scheduler->millis();
 
-    // if we did not get a message, and the idle timer has expired, re-init
+    // if we did not get a message, and the idle timer of 1.2 seconds has expired, re-init
     if (!result) {
-        if ((tnow - _idleTimer) > idleTimeout) {
+        if ((tnow - _idleTimer) > 1200) {
             Debug("gps read timeout %lu %lu", (unsigned long)tnow, (unsigned long)_idleTimer);
             _status = NO_GPS;
 

libraries/AP_GPS/GPS.h

@@ -125,14 +125,6 @@ public:
     virtual void setHIL(uint32_t time, float latitude, float longitude, float altitude,
                         float ground_speed, float ground_course, float speed_3d, uint8_t num_sats);
 
-    /// Time in milliseconds after which we will assume the GPS is no longer
-    /// sending us updates and attempt a re-init.
-    ///
-    /// 1200ms allows a small amount of slack over the worst-case 1Hz update
-    /// rate.
-    ///
-    uint32_t idleTimeout;
-
     // components of velocity in 2D, in m/s
     float velocity_north(void) {
         return _status >= GPS_OK_FIX_2D ? _velocity_north : 0;