diff --git a/libraries/mbed/targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/system/system.c b/libraries/mbed/targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/system/system.c
index 484dcf054b..c2695a4ee0 100644
--- a/libraries/mbed/targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/system/system.c
+++ b/libraries/mbed/targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/system/system.c
@@ -45,6 +45,7 @@
  */
 
 #include <system.h>
+#include <toolchain.h>
 
 /**
  * \internal