diff --git a/src/systemcmds/serial_test/.gitignore b/src/systemcmds/serial_test/.gitignore
new file mode 100644
index 0000000000..ab9845d6fe
--- /dev/null
+++ b/src/systemcmds/serial_test/.gitignore
@@ -0,0 +1,3 @@
+
+/serial_test
+
diff --git a/src/systemcmds/serial_test/serial_test.c b/src/systemcmds/serial_test/serial_test.c
index 139ba51f88..89a3b85f1d 100644
--- a/src/systemcmds/serial_test/serial_test.c
+++ b/src/systemcmds/serial_test/serial_test.c
@@ -516,7 +516,7 @@ static void dump_serial_port_stats(void)
 #if !defined(__PX4_NUTTX)
 	struct serial_icounter_struct icount = { 0 };
 
-	int ret = ioctl(_fd, TIOCGICOUNT, &icount);
+	int ret = ioctl(g_mod._fd, TIOCGICOUNT, &icount);
 
 	if (ret != -1) {
 		printf("%s: TIOCGICOUNT: ret=%i, rx=%i, tx=%i, frame = %i, overrun = %i, parity = %i, brk = %i, buf_overrun = %i\n",