diff --git a/src/modules/mavlink/mavlink_main_linux.cpp b/src/modules/mavlink/mavlink_main_linux.cpp
index e251ceaf5e..99e689e74e 100644
--- a/src/modules/mavlink/mavlink_main_linux.cpp
+++ b/src/modules/mavlink/mavlink_main_linux.cpp
@@ -1657,7 +1657,7 @@ Mavlink::display_status()
 {
 
 	if (_rstatus.heartbeat_time > 0) {
-		printf("\tGCS heartbeat:\t%llu us ago\n", hrt_elapsed_time(&_rstatus.heartbeat_time));
+		printf("\tGCS heartbeat:\t%llu us ago\n", (unsigned long long)hrt_elapsed_time(&_rstatus.heartbeat_time));
 	}
 
 	printf("\tmavlink chan: #%u\n", _channel);
diff --git a/src/platforms/linux/tests/hrt_test/hrt_test.cpp b/src/platforms/linux/tests/hrt_test/hrt_test.cpp
index d5e446bcc9..baa8670332 100644
--- a/src/platforms/linux/tests/hrt_test/hrt_test.cpp
+++ b/src/platforms/linux/tests/hrt_test/hrt_test.cpp
@@ -53,14 +53,14 @@ int HRTTest::main()
 	hrt_abstime t = hrt_absolute_time();
 	usleep(1000000);
 	hrt_abstime elt = hrt_elapsed_time(&t);
-	printf("Elapsed time %llu in 1 sec (usleep)\n", elt);
-	printf("Start time %llu\n", t);
+	printf("Elapsed time %llu in 1 sec (usleep)\n", (unsigned long long)elt);
+	printf("Start time %llu\n", (unsigned long long)t);
 
 	t = hrt_absolute_time();
 	sleep(1);
 	elt = hrt_elapsed_time(&t);
-	printf("Elapsed time %llu in 1 sec (sleep)\n", elt);
-	printf("Start time %llu\n", t);
+	printf("Elapsed time %llu in 1 sec (sleep)\n", (unsigned long long)elt);
+	printf("Start time %llu\n", (unsigned long long)t);
 
 	return 0;
 }