diff --git a/libuavcan_drivers/linux/include/uavcan_linux/clock.hpp b/libuavcan_drivers/linux/include/uavcan_linux/clock.hpp
index c6f7f89202..fc8e620618 100644
--- a/libuavcan_drivers/linux/include/uavcan_linux/clock.hpp
+++ b/libuavcan_drivers/linux/include/uavcan_linux/clock.hpp
@@ -2,6 +2,8 @@
  * Copyright (C) 2014 Pavel Kirienko <pavel.kirienko@gmail.com>
  */
 
+#pragma once
+
 #include <cassert>
 #include <ctime>
 #include <sys/time.h>