diff --git a/include/ieee80211.h b/include/ieee80211.h
index ed317f4..028fbc6 100644
--- a/include/ieee80211.h
+++ b/include/ieee80211.h
@@ -780,18 +780,18 @@ join_res:
 #define PORT_FMT "%u"
 #define PORT_ARG(x) ntohs(*((u16 *)(x)))
 
-extern __inline int is_multicast_mac_addr(const u8 *addr)
+static inline int is_multicast_mac_addr(const u8 *addr)
 {
 	return (addr[0] != 0xff) && (0x01 & addr[0]);
 }
 
-extern __inline int is_broadcast_mac_addr(const u8 *addr)
+static inline int is_broadcast_mac_addr(const u8 *addr)
 {
 	return ((addr[0] == 0xff) && (addr[1] == 0xff) && (addr[2] == 0xff) &&   \
 		(addr[3] == 0xff) && (addr[4] == 0xff) && (addr[5] == 0xff));
 }
 
-extern __inline int is_zero_mac_addr(const u8 *addr)
+static inline int is_zero_mac_addr(const u8 *addr)
 {
 	return ((addr[0] == 0x00) && (addr[1] == 0x00) && (addr[2] == 0x00) &&   \
 		(addr[3] == 0x00) && (addr[4] == 0x00) && (addr[5] == 0x00));