diff --git a/examples/get_af_ninet.c b/examples/get_af_ninet.c
index d245f2d86512740bf03a98febb7fe0f6c2337703..83a33304fc61aba336258ebbf8115b671106450e 100644
--- a/examples/get_af_ninet.c
+++ b/examples/get_af_ninet.c
@@ -69,9 +69,7 @@ int get_af_ninet(void)
 
 int main(int argc, char **argv)
 {
-	int af_ninet = get_af_ninet();
-
-	printf("af_ninet=%d\n\n", g_af_ninet);
+	printf("af_ninet=%d\n\n", get_af_ninet());
 	return 0;
 }
 
diff --git a/examples/nip_lib.c b/examples/nip_lib.c
index 1c679a0a576e562cfa71053e535de00bfa16f7af..d41496885f92ec53fafda17a4a30547e97d89dd4 100644
--- a/examples/nip_lib.c
+++ b/examples/nip_lib.c
@@ -96,8 +96,7 @@ int nip_addr_fmt(char *addr_str, struct nip_addr *sap, int addrlen_input)
 	first_byte += addr_str[1];
 	if (first_byte <= ADDR_FIRST_DC)
 		addrlen = NIP_ADDR_LEN_1;
-	else if ((first_byte > ADDR_FIRST_DC && first_byte <= ADDR_FIRST_F0) ||
-		 (first_byte == ADDR_FIRST_FF))
+	else if (first_byte <= ADDR_FIRST_F0 || first_byte == ADDR_FIRST_FF)
 		addrlen = NIP_ADDR_LEN_2;
 	else if (first_byte == ADDR_FIRST_F1)
 		addrlen = NIP_ADDR_LEN_3;
@@ -130,7 +129,6 @@ int nip_addr_fmt(char *addr_str, struct nip_addr *sap, int addrlen_input)
 
 int nip_get_addr(char **args, struct nip_addr *addr)
 {
-	int ret;
 	unsigned int len;
 	char *sp = *args;
 	int addrlen_input = 0;
diff --git a/src/linux/net/newip/tcp_nip_input.c b/src/linux/net/newip/tcp_nip_input.c
index 7f6333f21e4a1092da9e5d19918211df08adbd7c..1b01ce13c6921e5bed12aeaae05293bc6a56ab97 100644
--- a/src/linux/net/newip/tcp_nip_input.c
+++ b/src/linux/net/newip/tcp_nip_input.c
@@ -118,10 +118,10 @@ static void tcp_nip_overlap_handle(struct tcp_sock *tp, struct sk_buff *skb)
 static void tcp_nip_ofo_queue(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
-	struct sk_buff *skb;
 
 	while (tp->nip_out_of_order_queue) {
-		skb = tp->nip_out_of_order_queue;
+		struct sk_buff *skb = tp->nip_out_of_order_queue;
+
 		if (after(TCP_SKB_CB(tp->nip_out_of_order_queue)->seq, tp->rcv_nxt))
 			return;
 		tp->nip_out_of_order_queue = tp->nip_out_of_order_queue->next;
@@ -892,8 +892,8 @@ static inline bool tcp_nip_may_update_window(const struct tcp_sock *tp,
 		(ack_seq == tp->snd_wl1 && nwin > tp->snd_wnd);
 }
 
-static int tcp_nip_ack_update_window(struct sock *sk, const struct sk_buff *skb, u32 ack,
-				     u32 ack_seq)
+static void tcp_nip_ack_update_window(struct sock *sk, const struct sk_buff *skb, u32 ack,
+				      u32 ack_seq)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	int flag = 0;
@@ -912,8 +912,6 @@ static int tcp_nip_ack_update_window(struct sock *sk, const struct sk_buff *skb,
 			tp->pred_flags = 0;
 		}
 	}
-
-	return flag;
 }
 
 /* Check whether the ACK returned by the packet is detected
@@ -1135,7 +1133,7 @@ static void tcp_nip_ack_calc_ssthresh(struct sock *sk, u32 ack, int icsk_rto_las
 	}
 }
 
-static int tcp_nip_ack(struct sock *sk, const struct sk_buff *skb, int flag)
+static int tcp_nip_ack(struct sock *sk, const struct sk_buff *skb)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct tcp_nip_common *ntp = &tcp_nip_sk(sk)->common;
@@ -1145,16 +1143,15 @@ static int tcp_nip_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	u32 ack = TCP_SKB_CB(skb)->ack_seq;
 	int prior_packets = tp->packets_out;
 	ktime_t skb_snd_tstamp = 0;
-	int icsk_rto_last;
 
 	if (before(ack, prior_snd_una))
 		return 0;
 	if (after(ack, tp->snd_nxt))
 		return -1;
 
-	(void)tcp_nip_ack_update_window(sk, skb, ack, ack_seq);
-	icsk->icsk_probes_out = 0; // probe0 cnt
-	ntp->nip_keepalive_out = 0; // keepalive cnt
+	tcp_nip_ack_update_window(sk, skb, ack, ack_seq);
+	icsk->icsk_probes_out = 0;  /* probe0 cnt */
+	ntp->nip_keepalive_out = 0; /* keepalive cnt */
 	tp->rcv_tstamp = tcp_jiffies32;
 
 	/* maybe zero window probe */
@@ -1167,6 +1164,8 @@ static int tcp_nip_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	}
 
 	if (after(ack, prior_snd_una)) {
+		int icsk_rto_last;
+
 		icsk->icsk_retransmits = 0;
 		tp->retrans_stamp = tcp_time_stamp(tp);
 		tp->rcv_tstamp = tcp_jiffies32;
@@ -1297,7 +1296,7 @@ void tcp_nip_rcv_established(struct sock *sk, struct sk_buff *skb,
 	if (!tcp_nip_validate_incoming(sk, skb, th, 1))
 		return;
 
-	if (tcp_nip_ack(sk, skb, 0) < 0)
+	if (tcp_nip_ack(sk, skb) < 0)
 		goto discard;
 
 	tcp_nip_data_queue(sk, skb);
@@ -1427,7 +1426,7 @@ static int tcp_nip_rcv_synsent_state_process(struct sock *sk, struct sk_buff *sk
 
 		tcp_init_wl(tp, TCP_SKB_CB(skb)->seq);
 
-		tcp_nip_ack(sk, skb, FLAG_SLOWPATH);
+		tcp_nip_ack(sk, skb);
 		tp->nip_out_of_order_queue = NULL;
 		/* The next data number expected to be accepted is +1 */
 		tp->rcv_nxt = TCP_SKB_CB(skb)->seq + 1;
@@ -1556,7 +1555,7 @@ int tcp_nip_rcv_state_process(struct sock *sk, struct sk_buff *skb)
 	if (!tcp_nip_validate_incoming(sk, skb, th, 0))
 		return 0;
 
-	acceptable = tcp_nip_ack(sk, skb, 0);
+	acceptable = tcp_nip_ack(sk, skb);
 
 	/* If the third handshake ACK is invalid, 1 is returned
 	 * and the SKB is discarded in tcp_nip_rcv
diff --git a/src/linux/net/newip/tcp_nip_output.c b/src/linux/net/newip/tcp_nip_output.c
index 5b34d6bd2e14bcde56bc22e71add1ed3b0a14d3d..2db7b0c6fb0ab86c84f8a0dc457b13317cac0198 100644
--- a/src/linux/net/newip/tcp_nip_output.c
+++ b/src/linux/net/newip/tcp_nip_output.c
@@ -39,8 +39,6 @@ struct tcp_nip_out_options {
 	u8 ws;			/* window scale, 0 to disable, If the window is enlarged,
 				 * 0 indicates that the option is disabled
 				 */
-	u8 hash_size;		/* bytes in hash_location */
-	__u8 *hash_location;	/* temporary pointer, overloaded */
 	__u32 tsval, tsecr;	/* need to include OPTION_TS */
 };
 
@@ -542,9 +540,8 @@ static int __tcp_nip_transmit_skb(struct sock *sk, struct sk_buff *skb,
 		tcp_nip_event_ack_sent(sk, tcp_skb_pcount(skb), rcv_nxt);
 
 	 /* There's data to send */
-	if (skb->len != tcp_header_size) {
+	if (skb->len != tcp_header_size)
 		tp->data_segs_out += tcp_skb_pcount(skb);
-	}
 
 	memset(skb->cb, 0, sizeof(struct ninet_skb_parm));
 	err = icsk->icsk_af_ops->queue_xmit(sk, skb, &inet->cork.fl);
@@ -607,7 +604,6 @@ int __tcp_nip_connect(struct sock *sk)
 
 	tp->snd_nxt = tp->write_seq;
 	tp->pushed_seq = tp->write_seq;
-	buff = tcp_nip_send_head(sk);
 
 	TCP_INC_STATS(sock_net(sk), TCP_MIB_ACTIVEOPENS);
 
@@ -1040,7 +1036,6 @@ static bool tcp_nip_write_xmit(struct sock *sk, unsigned int mss_now, int nonagl
 	struct sk_buff *skb;
 	u32 snd_num = g_nip_tcp_snd_win_enable ? (ntp->nip_ssthresh / mss_now) : 0xFFFFFFFF;
 	u32 last_nip_ssthresh = ntp->nip_ssthresh;
-	bool snd_wnd_ready;
 	static const char * const str[] = {"can`t send pkt because no window",
 					   "have window to send pkt"};
 
@@ -1062,6 +1057,8 @@ static bool tcp_nip_write_xmit(struct sock *sk, unsigned int mss_now, int nonagl
 	}
 
 	while ((skb = tcp_nip_send_head(sk)) && (snd_num--)) {
+		bool snd_wnd_ready;
+
 		tcp_nip_init_tso_segs(skb, mss_now);
 		snd_wnd_ready = tcp_nip_snd_wnd_test(tp, skb, mss_now);
 		DEBUG("%s %s, skb->len=%u", __func__, (snd_wnd_ready ? str[1] : str[0]), skb->len);
@@ -1105,7 +1102,7 @@ int __tcp_nip_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	unsigned int cur_mss;
-	int diff, len, err;
+	int len, err;
 
 	if (before(TCP_SKB_CB(skb)->seq, tp->snd_una)) {
 		if (unlikely(before(TCP_SKB_CB(skb)->end_seq, tp->snd_una))) {
@@ -1128,7 +1125,8 @@ int __tcp_nip_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
 				 skb, len, cur_mss, GFP_ATOMIC))
 			return -ENOMEM; /* We'll try again later. */
 	} else {
-		diff = tcp_skb_pcount(skb);
+		int diff = tcp_skb_pcount(skb);
+
 		tcp_nip_set_skb_tso_segs(skb, cur_mss);
 		diff -= tcp_skb_pcount(skb);
 		if (diff)