diff --git a/components/802.15.4_RF/mcr20a-rf-driver/source/MCR20Drv.c b/components/802.15.4_RF/mcr20a-rf-driver/source/MCR20Drv.c
index bbd0d46b96..90633a0205 100644
--- a/components/802.15.4_RF/mcr20a-rf-driver/source/MCR20Drv.c
+++ b/components/802.15.4_RF/mcr20a-rf-driver/source/MCR20Drv.c
@@ -45,6 +45,7 @@
 #if defined(MBED_CONF_NANOSTACK_CONFIGURATION) && DEVICE_SPI && DEVICE_INTERRUPTIN && defined(MBED_CONF_RTOS_PRESENT)
 
 #include "platform/mbed_critical.h"
+#include <string.h>
 
 /*****************************************************************************
 *                               PRIVATE VARIABLES                           *