diff --git a/portable/GCC/ARM_CA9/port.c b/portable/GCC/ARM_CA9/port.c
index 78c8aea74..6dbccf3df 100644
--- a/portable/GCC/ARM_CA9/port.c
+++ b/portable/GCC/ARM_CA9/port.c
@@ -28,6 +28,7 @@
 
 /* Standard includes. */
 #include <stdlib.h>
+#include <string.h>
 
 /* Scheduler includes. */
 #include "FreeRTOS.h"