diff --git a/arch/arm/src/common/up_unblocktask.c b/arch/arm/src/common/up_unblocktask.c
index f907c6161f4..32176f152e7 100644
--- a/arch/arm/src/common/up_unblocktask.c
+++ b/arch/arm/src/common/up_unblocktask.c
@@ -43,6 +43,7 @@
 #include <debug.h>
 #include <nuttx/arch.h>
 #include "os_internal.h"
+#include "clock_internal.h"
 #include "up_internal.h"
 
 /************************************************************