diff --git a/boards/px4/sitl/src/sitl_led.c b/boards/px4/sitl/src/sitl_led.c
index c9d3f4d053..f86e877764 100644
--- a/boards/px4/sitl/src/sitl_led.c
+++ b/boards/px4/sitl/src/sitl_led.c
@@ -50,7 +50,7 @@ __END_DECLS
 
 static bool _led_state[2] = { false, false };
 
-__EXPORT void led_init()
+__EXPORT void led_init(void)
 {
 	PX4_DEBUG("LED_INIT");
 }
diff --git a/platforms/common/work_queue/hrt_thread.c b/platforms/common/work_queue/hrt_thread.c
index 8438b0ae2c..8da8b415d1 100644
--- a/platforms/common/work_queue/hrt_thread.c
+++ b/platforms/common/work_queue/hrt_thread.c
@@ -113,7 +113,7 @@ static void _sighandler(int sig_num)
  *
  ****************************************************************************/
 
-static void hrt_work_process()
+static void hrt_work_process(void)
 {
 	struct wqueue_s *wqueue = &g_hrt_work;
 	volatile struct work_s *work;
diff --git a/platforms/common/work_queue/work_thread.c b/platforms/common/work_queue/work_thread.c
index b1e0e72355..5109b6ad8a 100644
--- a/platforms/common/work_queue/work_thread.c
+++ b/platforms/common/work_queue/work_thread.c
@@ -338,7 +338,7 @@ int work_usrthread(int argc, char *argv[])
 
 #endif /* CONFIG_SCHED_USRWORK */
 
-uint32_t clock_systimer()
+uint32_t clock_systimer(void)
 {
 	//printf("clock_systimer: %0lx\n", hrt_absolute_time());
 	return (0x00000000ffffffff & hrt_absolute_time());
diff --git a/platforms/posix/include/hrt_work.h b/platforms/posix/include/hrt_work.h
index 6dd2ab5a09..7799d3815c 100644
--- a/platforms/posix/include/hrt_work.h
+++ b/platforms/posix/include/hrt_work.h
@@ -48,13 +48,13 @@ int hrt_work_queue(struct work_s *work, worker_t worker, void *arg, uint32_t usd
 void hrt_work_cancel(struct work_s *work);
 
 static inline void hrt_work_lock(void);
-static inline void hrt_work_lock()
+static inline void hrt_work_lock(void)
 {
 	px4_sem_wait(&_hrt_work_lock);
 }
 
 static inline void hrt_work_unlock(void);
-static inline void hrt_work_unlock()
+static inline void hrt_work_unlock(void)
 {
 	px4_sem_post(&_hrt_work_lock);
 }
diff --git a/src/lib/rc/rc_tests/RCTest.cpp b/src/lib/rc/rc_tests/RCTest.cpp
index 07c45d33c0..5894bf7549 100644
--- a/src/lib/rc/rc_tests/RCTest.cpp
+++ b/src/lib/rc/rc_tests/RCTest.cpp
@@ -359,7 +359,6 @@ bool RCTest::sbus2Test()
 	bool sbus_frame_drop;
 	uint16_t max_channels = sizeof(rc_values) / sizeof(rc_values[0]);
 
-	int rate_limiter = 0;
 	unsigned last_drop = 0;
 
 	while (EOF != (ret = fscanf(fp, "%f,%x,,", &f, &x))) {
@@ -390,7 +389,6 @@ bool RCTest::sbus2Test()
 			last_drop = sbus_frame_drops + sbus_frame_resets;
 		}
 
-		rate_limiter++;
 	}
 
 	ut_test(ret == EOF);