diff --git a/sys/include/net/ieee802154.h b/sys/include/net/ieee802154.h
index ce67c103bb185779d36a40115a668299adc3edf0..a11330cd01bbb08dafb6560d05991ab0d2f546d5 100644
--- a/sys/include/net/ieee802154.h
+++ b/sys/include/net/ieee802154.h
@@ -275,6 +275,7 @@ static inline eui64_t *ieee802154_get_iid(eui64_t *eui64, const uint8_t *addr,
             eui64->uint8[0] = addr[i++] ^ 0x02;
             eui64->uint8[1] = addr[i++];
 
+            /* Falls through. */
         case 2:
             eui64->uint8[2] = 0;
             eui64->uint8[3] = 0xff;