SITL: use PACKED attribute instead of pragma pack

libraries/AP_HAL_AVR_SITL/sitl_gps.cpp

@@ -145,8 +145,7 @@ static uint32_t millis_time_of_week(void)
  */
 void SITL_State::_update_gps_ubx(const struct gps_data *d)
 {
-	#pragma pack(push,1)
-	struct ubx_nav_posllh {
+	struct PACKED ubx_nav_posllh {
 		uint32_t	time; // GPS msToW
 		int32_t		longitude;
 		int32_t		latitude;
@@ -155,7 +154,7 @@ void SITL_State::_update_gps_ubx(const struct gps_data *d)
 		uint32_t	horizontal_accuracy;
 		uint32_t	vertical_accuracy;
 	} pos;
-	struct ubx_nav_status {
+	struct PACKED ubx_nav_status {
 		uint32_t	time;				// GPS msToW
 		uint8_t		fix_type;
 		uint8_t		fix_status;
@@ -164,7 +163,7 @@ void SITL_State::_update_gps_ubx(const struct gps_data *d)
 		uint32_t	time_to_first_fix;
 		uint32_t	uptime;				// milliseconds
 	} status;
-	struct ubx_nav_velned {
+	struct PACKED ubx_nav_velned {
 		uint32_t	time;				// GPS msToW
 		int32_t		ned_north;
 		int32_t		ned_east;
@@ -175,7 +174,7 @@ void SITL_State::_update_gps_ubx(const struct gps_data *d)
 		uint32_t	speed_accuracy;
 		uint32_t	heading_accuracy;
 	} velned;
-	struct ubx_nav_solution {
+	struct PACKED ubx_nav_solution {
 		uint32_t time;
 		int32_t time_nsec;
 		int16_t week;
@@ -194,8 +193,7 @@ void SITL_State::_update_gps_ubx(const struct gps_data *d)
 		uint8_t satellites;
 		uint32_t res2;
 	} sol;
-	#pragma pack(pop)
-        const uint8_t MSG_POSLLH = 0x2;
+	const uint8_t MSG_POSLLH = 0x2;
 	const uint8_t MSG_STATUS = 0x3;
 	const uint8_t MSG_VELNED = 0x12;
         const uint8_t MSG_SOL = 0x6;
@@ -266,8 +264,7 @@ static void mtk_checksum(const uint8_t *data, uint8_t n, uint8_t *ck_a, uint8_t
  */
 void SITL_State::_update_gps_mtk(const struct gps_data *d)
 {
-    #pragma pack(push,1)
-    struct mtk_msg {
+    struct PACKED mtk_msg {
 	    uint8_t preamble1;
 	    uint8_t preamble2;
 	    uint8_t msg_class;
@@ -283,7 +280,6 @@ void SITL_State::_update_gps_mtk(const struct gps_data *d)
 	    uint8_t ck_a;
 	    uint8_t ck_b;
     } p;
-    #pragma pack(pop)
 
 	p.preamble1     = 0xb5;
 	p.preamble2     = 0x62;
@@ -322,8 +318,7 @@ void SITL_State::_update_gps_mtk(const struct gps_data *d)
  */
 void SITL_State::_update_gps_mtk16(const struct gps_data *d)
 {
-    #pragma pack(push,1)
-    struct mtk_msg {
+    struct PACKED mtk_msg {
 	    uint8_t preamble1;
 	    uint8_t preamble2;
 	    uint8_t size;
@@ -340,7 +335,6 @@ void SITL_State::_update_gps_mtk16(const struct gps_data *d)
 	    uint8_t ck_a;
 	    uint8_t ck_b;
     } p;
-    #pragma pack(pop)
 
 	p.preamble1     = 0xd0;
 	p.preamble2     = 0xdd;
@@ -380,8 +374,7 @@ void SITL_State::_update_gps_mtk16(const struct gps_data *d)
  */
 void SITL_State::_update_gps_mtk19(const struct gps_data *d)
 {
-    #pragma pack(push,1)
-    struct mtk_msg {
+    struct PACKED mtk_msg {
 	    uint8_t preamble1;
 	    uint8_t preamble2;
 	    uint8_t size;
@@ -398,7 +391,6 @@ void SITL_State::_update_gps_mtk19(const struct gps_data *d)
 	    uint8_t ck_a;
 	    uint8_t ck_b;
     } p;
-    #pragma pack(pop)
 
 	p.preamble1     = 0xd1;
 	p.preamble2     = 0xdd;