diff --git a/hal/hal_intf.c b/hal/hal_intf.c
index c30fa68..daa42f9 100644
--- a/hal/hal_intf.c
+++ b/hal/hal_intf.c
@@ -1082,7 +1082,7 @@ s32 c2h_handler(_adapter *adapter, u8 id, u8 seq, u8 plen, u8 *payload)
 	case C2H_EXTEND:
 		sub_id = payload[0];
 		/* no handle, goto default */
-		// Intentional fallthrough
+		__attribute__ ((__fallthrough__));
 	default:
 		if (phydm_c2H_content_parsing(adapter_to_phydm(adapter), id, plen, payload) != TRUE)
 			ret = _FAIL;
diff --git a/os_dep/linux/ioctl_cfg80211.c b/os_dep/linux/ioctl_cfg80211.c
index 4975ac4..54d0e17 100644
--- a/os_dep/linux/ioctl_cfg80211.c
+++ b/os_dep/linux/ioctl_cfg80211.c
@@ -2471,7 +2471,7 @@ static int cfg80211_rtw_change_iface(struct wiphy *wiphy,
 	case NL80211_IFTYPE_P2P_CLIENT:
 		is_p2p = _TRUE;
 	#endif
-	// Intentional fallthrough
+	__attribute__ ((__fallthrough__));
 	case NL80211_IFTYPE_STATION:
 		networkType = Ndis802_11Infrastructure;
 
@@ -2496,7 +2496,7 @@ static int cfg80211_rtw_change_iface(struct wiphy *wiphy,
 	case NL80211_IFTYPE_P2P_GO:
 		is_p2p = _TRUE;
 	#endif
-	// Intentional fallthrough
+	__attribute__ ((__fallthrough__));
 	case NL80211_IFTYPE_AP:
 		networkType = Ndis802_11APMode;