diff --git a/include/nuttx/rtc.h b/include/nuttx/rtc.h
index 46a7c8a2ffe..5082b4d2d70 100644
--- a/include/nuttx/rtc.h
+++ b/include/nuttx/rtc.h
@@ -107,7 +107,7 @@
  ****************************************************************************/
 /* The form of an alarm callback */
 
-typedef void (alarmcb_t)(void);
+typedef FAR void (*alarmcb_t)(void);
 
 /****************************************************************************
  * Public Variables