diff --git a/sys/include/can/device.h b/sys/include/can/device.h
index 00c7e2b1174981048ff0c49896f0417abd405d38..7a484ae03f32d0a343facdc01d5763ee02dcf40f 100644
--- a/sys/include/can/device.h
+++ b/sys/include/can/device.h
@@ -46,7 +46,7 @@ extern "C" {
 /**
  * Maximum number of interfaces which can be registered on DLL
  */
-#define CAN_DLL_NUMOF       (1U)
+#define CAN_DLL_NUMOF       (1)
 #endif
 
 /**