diff --git a/features/nanostack/coap-service/source/coap_connection_handler.c b/features/nanostack/coap-service/source/coap_connection_handler.c
index 0942dc8e21..fe4bbbde1a 100644
--- a/features/nanostack/coap-service/source/coap_connection_handler.c
+++ b/features/nanostack/coap-service/source/coap_connection_handler.c
@@ -408,8 +408,9 @@ static int send_to_real_socket(int8_t socket_id, const ns_address_t *address, co
         .msg_iovlen = 1
     };
 
+    uint8_t ancillary_databuffer[NS_CMSG_SPACE(sizeof(ns_in6_pktinfo_t))];
+
     if (memcmp(source_address, ns_in6addr_any, 16)) {
-        uint8_t ancillary_databuffer[NS_CMSG_SPACE(sizeof(ns_in6_pktinfo_t))];
         ns_cmsghdr_t *cmsg;
         ns_in6_pktinfo_t *pktinfo;
 
diff --git a/features/nanostack/nanostack-hal-mbed-cmsis-rtos/arm_hal_fhss_timer.cpp b/features/nanostack/nanostack-hal-mbed-cmsis-rtos/arm_hal_fhss_timer.cpp
index 3c0f61aaa7..81e4f7ee76 100644
--- a/features/nanostack/nanostack-hal-mbed-cmsis-rtos/arm_hal_fhss_timer.cpp
+++ b/features/nanostack/nanostack-hal-mbed-cmsis-rtos/arm_hal_fhss_timer.cpp
@@ -14,6 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 #include "ns_types.h"
 #include "fhss_api.h"
 #include "fhss_config.h"
@@ -70,7 +71,7 @@ static fhss_timeout_s *allocate_timeout(void)
 {
     for (int i = 0; i < NUMBER_OF_SIMULTANEOUS_TIMEOUTS; i++) {
         if (fhss_timeout[i].fhss_timer_callback == NULL) {
-            memset(&fhss_timeout[i], sizeof(fhss_timeout_s), 0);
+            memset(&fhss_timeout[i], 0, sizeof(fhss_timeout_s));
             return &fhss_timeout[i];
         }
     }
@@ -170,3 +171,4 @@ fhss_timer_t fhss_functions = {
     .fhss_get_timestamp = platform_fhss_timestamp_read,
     .fhss_resolution_divider = 1
 };
+
diff --git a/features/nanostack/nanostack-hal-mbed-cmsis-rtos/arm_hal_random.c b/features/nanostack/nanostack-hal-mbed-cmsis-rtos/arm_hal_random.c
index 804f1485ab..773a2b70d3 100644
--- a/features/nanostack/nanostack-hal-mbed-cmsis-rtos/arm_hal_random.c
+++ b/features/nanostack/nanostack-hal-mbed-cmsis-rtos/arm_hal_random.c
@@ -19,6 +19,12 @@
 
 #include "mbedtls/entropy_poll.h"
 
+#ifdef MBEDTLS_ENTROPY_HARDWARE_ALT
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#endif
+#endif
+
 void arm_random_module_init(void)
 {
 }