Fixed some sitl init bugs.

src/modules/sensors/sensors.cpp

@@ -1250,7 +1250,7 @@ Sensors::vehicle_control_mode_poll()
 void
 Sensors::parameter_update_poll(bool forced)
 {
-	bool param_updated;
+	bool param_updated=false;
 
 	/* Check if any parameter has changed */
 	orb_check(_params_sub, &param_updated);

src/modules/simulator/simulator_mavlink.cpp

@@ -463,10 +463,12 @@ void Simulator::pollForMAVLinkMessages(bool publish)
 	char serial_buf[1024];
 
 	struct pollfd fds[2];
+	memset(fds, 0, sizeof(fds));
 	unsigned fd_count = 1;
 	fds[0].fd = _fd;
 	fds[0].events = POLLIN;
 
+
 	if (serial_fd >= 0) {
 		fds[1].fd = serial_fd;
 		fds[1].events = POLLIN;

src/platforms/posix/drivers/adcsim/adcsim.cpp

@@ -111,6 +111,7 @@ private:
 
 ADCSIM::ADCSIM(uint32_t channels) :
 	VDev("adcsim", ADCSIM0_DEVICE_PATH),
+	_call(),
 	_sample_perf(perf_alloc(PC_ELAPSED, "adc_samples")),
 	_channel_count(0),
 	_samples(nullptr)

src/platforms/posix/px4_layer/px4_posix_tasks.cpp

@@ -81,9 +81,7 @@ typedef struct {
 
 static void *entry_adapter(void *ptr)
 {
-	pthdata_t *data;
-	data = (pthdata_t *) ptr;
-
+	pthdata_t *data = (pthdata_t *) ptr;
 	data->entry(data->argc, data->argv);
 	free(ptr);
 	PX4_DEBUG("Before px4_task_exit");