From da19974e815f8b775a96cad79ad062a6ba922909 Mon Sep 17 00:00:00 2001
From: Sylvain Rochet <gradator@gradator.net>
Date: Sun, 12 Oct 2014 19:54:43 +0200
Subject: [PATCH] fixed bug #43235, cleared compiler warnings when using gcc
 with -Wextra option

---
 src/netif/ppp/auth.c     | 10 ++++++++--
 src/netif/ppp/chap-md5.c |  3 +++
 src/netif/ppp/chap-new.c | 11 ++++++++---
 src/netif/ppp/chap_ms.c  | 10 +++++++++-
 src/netif/ppp/eap.c      | 16 ++++++++++------
 src/netif/ppp/ipcp.c     |  3 ++-
 src/netif/ppp/ipv6cp.c   | 28 ++++++++++++++--------------
 src/netif/ppp/lcp.c      |  5 ++++-
 src/netif/ppp/ppp.c      |  2 ++
 src/netif/ppp/pppoe.c    |  2 +-
 src/netif/ppp/pppol2tp.c |  5 +++++
 src/netif/ppp/upap.c     | 19 +++++++++++++++----
 src/netif/ppp/utils.c    |  4 +++-
 13 files changed, 84 insertions(+), 34 deletions(-)

diff --git a/src/netif/ppp/auth.c b/src/netif/ppp/auth.c
index 4cbf0afb..830e21fd 100644
--- a/src/netif/ppp/auth.c
+++ b/src/netif/ppp/auth.c
@@ -546,6 +546,7 @@ set_permitted_number(argv)
  * An Open on LCP has requested a change from Dead to Establish phase.
  */
 void link_required(ppp_pcb *pcb) {
+    LWIP_UNUSED_ARG(pcb);
 }
 
 #if 0
@@ -1003,6 +1004,7 @@ void continue_networks(ppp_pcb *pcb) {
  */
 void auth_peer_fail(ppp_pcb *pcb, int protocol) {
     int errcode = PPPERR_AUTHFAIL;
+    LWIP_UNUSED_ARG(protocol);
     /*
      * Authentication failure: take the link down
      */
@@ -1057,8 +1059,8 @@ void auth_peer_success(ppp_pcb *pcb, int protocol, int prot_flavor, char *name,
      * Save the authenticated name of the peer for later.
      */
     /* FIXME: do we need that ? */
-    if (namelen > sizeof(pcb->peer_authname) - 1)
-	namelen = sizeof(pcb->peer_authname) - 1;
+    if (namelen > (int)sizeof(pcb->peer_authname) - 1)
+	namelen = (int)sizeof(pcb->peer_authname) - 1;
     MEMCPY(pcb->peer_authname, name, namelen);
     pcb->peer_authname[namelen] = 0;
 #if 0 /* UNUSED */
@@ -1082,6 +1084,7 @@ void auth_peer_success(ppp_pcb *pcb, int protocol, int prot_flavor, char *name,
  */
 void auth_withpeer_fail(ppp_pcb *pcb, int protocol) {
     int errcode = PPPERR_AUTHFAIL;
+    LWIP_UNUSED_ARG(protocol);
     /*
      * We've failed to authenticate ourselves to our peer.
      *
@@ -1162,6 +1165,7 @@ void np_up(ppp_pcb *pcb, int proto) {
 #if PPP_IDLETIMELIMIT
     int tlim;
 #endif /* PPP_IDLETIMELIMIT */
+    LWIP_UNUSED_ARG(proto);
 
     if (pcb->num_np_up == 0) {
 	/*
@@ -1209,6 +1213,7 @@ void np_up(ppp_pcb *pcb, int proto) {
  * np_down - a network protocol has gone down.
  */
 void np_down(ppp_pcb *pcb, int proto) {
+    LWIP_UNUSED_ARG(proto);
     if (--pcb->num_np_up == 0) {
 #if PPP_IDLETIMELIMIT
 	UNTIMEOUT(check_idle, (void*)pcb);
@@ -1227,6 +1232,7 @@ void np_down(ppp_pcb *pcb, int proto) {
  * np_finished - a network protocol has finished using the link.
  */
 void np_finished(ppp_pcb *pcb, int proto) {
+    LWIP_UNUSED_ARG(proto);
     if (--pcb->num_np_open <= 0) {
 	/* no further use for the link: shut up shop. */
 	lcp_close(pcb, "No network protocols running");
diff --git a/src/netif/ppp/chap-md5.c b/src/netif/ppp/chap-md5.c
index f6361314..f7965490 100644
--- a/src/netif/ppp/chap-md5.c
+++ b/src/netif/ppp/chap-md5.c
@@ -70,6 +70,7 @@ static int chap_md5_verify_response(int id, char *name,
 	unsigned char idbyte = id;
 	unsigned char hash[MD5_HASH_SIZE];
 	int challenge_len, response_len;
+	LWIP_UNUSED_ARG(name);
 
 	challenge_len = *challenge++;
 	response_len = *response++;
@@ -98,6 +99,8 @@ static void chap_md5_make_response(unsigned char *response, int id, char *our_na
 	md5_context ctx;
 	unsigned char idbyte = id;
 	int challenge_len = *challenge++;
+	LWIP_UNUSED_ARG(our_name);
+	LWIP_UNUSED_ARG(private);
 
 	md5_starts(&ctx);
 	md5_update(&ctx, &idbyte, 1);
diff --git a/src/netif/ppp/chap-new.c b/src/netif/ppp/chap-new.c
index 052b4095..d4dbd7cc 100644
--- a/src/netif/ppp/chap-new.c
+++ b/src/netif/ppp/chap-new.c
@@ -106,7 +106,7 @@ static int chap_print_pkt(unsigned char *p, int plen,
 #endif /* PRINTPKT_SUPPORT */
 
 /* List of digest types that we know about */
-const static struct chap_digest_type* const chap_digests[] = {
+static const struct chap_digest_type* const chap_digests[] = {
     &md5_digest,
 #if MSCHAP_SUPPORT
     &chapms_digest,
@@ -409,7 +409,11 @@ static int chap_verify_response(char *name, char *ourname, int id,
 		ppp_error("No CHAP secret found for authenticating %q", name);
 		return 0;
 	}
-#endif
+#else
+	/* only here to clean compiler warnings */
+	LWIP_UNUSED_ARG(ourname);
+	secret_len = 0;
+#endif /* 0 */
 	ok = digest->verify_response(id, name, secret, secret_len, challenge,
 				     response, message, message_space);
 	memset(secret, 0, sizeof(secret));
@@ -486,6 +490,7 @@ static void chap_respond(ppp_pcb *pcb, int id,
 static void chap_handle_status(ppp_pcb *pcb, int code, int id,
 		   unsigned char *pkt, int len) {
 	const char *msg = NULL;
+	LWIP_UNUSED_ARG(id);
 
 	if ((pcb->chap_client.flags & (AUTH_DONE|AUTH_STARTED|LOWERUP))
 	    != (AUTH_STARTED|LOWERUP))
@@ -590,7 +595,7 @@ static int chap_print_pkt(unsigned char *p, int plen,
 	if (len < CHAP_HDRLEN || len > plen)
 		return 0;
 
-	if (code >= 1 && code <= sizeof(chap_code_names) / sizeof(char *))
+	if (code >= 1 && code <= (int)sizeof(chap_code_names) / (int)sizeof(char *))
 		printer(arg, " %s", chap_code_names[code-1]);
 	else
 		printer(arg, " code=0x%x", code);
diff --git a/src/netif/ppp/chap_ms.c b/src/netif/ppp/chap_ms.c
index 2467aa54..7935de65 100644
--- a/src/netif/ppp/chap_ms.c
+++ b/src/netif/ppp/chap_ms.c
@@ -208,6 +208,8 @@ static int chapms_verify_response(int id, char *name,
 	unsigned char md[MS_CHAP_RESPONSE_LEN];
 	int diff;
 	int challenge_len, response_len;
+	LWIP_UNUSED_ARG(id);
+	LWIP_UNUSED_ARG(name);
 
 	challenge_len = *challenge++;	/* skip length, is 8 */
 	response_len = *response++;
@@ -254,6 +256,7 @@ static int chapms2_verify_response(int id, char *name,
 	unsigned char md[MS_CHAP2_RESPONSE_LEN];
 	char saresponse[MS_AUTH_RESPONSE_LENGTH+1];
 	int challenge_len, response_len;
+	LWIP_UNUSED_ARG(id);
 
 	challenge_len = *challenge++;	/* skip length, is 16 */
 	response_len = *response++;
@@ -326,6 +329,9 @@ static int chapms2_verify_response(int id, char *name,
 static void chapms_make_response(unsigned char *response, int id, char *our_name,
 		     unsigned char *challenge, char *secret, int secret_len,
 		     unsigned char *private) {
+	LWIP_UNUSED_ARG(id);
+	LWIP_UNUSED_ARG(our_name);
+	LWIP_UNUSED_ARG(private);
 	challenge++;	/* skip length, should be 8 */
 	*response++ = MS_CHAP_RESPONSE_LEN;
 	ChapMS(challenge, secret, secret_len, response);
@@ -334,6 +340,7 @@ static void chapms_make_response(unsigned char *response, int id, char *our_name
 static void chapms2_make_response(unsigned char *response, int id, char *our_name,
 		      unsigned char *challenge, char *secret, int secret_len,
 		      unsigned char *private) {
+	LWIP_UNUSED_ARG(id);
 	challenge++;	/* skip length, should be 16 */
 	*response++ = MS_CHAP2_RESPONSE_LEN;
 	ChapMS2(challenge,
@@ -608,7 +615,7 @@ void GenerateAuthenticatorResponse(u_char PasswordHashHash[MD4_SIGNATURE_SIZE],
     sha1_finish(&sha1Context, Digest);
 
     /* Convert to ASCII hex string. */
-    for (i = 0; i < LWIP_MAX((MS_AUTH_RESPONSE_LENGTH / 2), sizeof(Digest)); i++)
+    for (i = 0; i < LWIP_MAX((MS_AUTH_RESPONSE_LENGTH / 2), (int)sizeof(Digest)); i++)
 	sprintf((char *)&authResponse[i * 2], "%02X", Digest[i]);
 }
 
@@ -821,6 +828,7 @@ void ChapMS2(u_char *rchallenge, u_char *PeerChallenge,
     /* ARGSUSED */
     u_char *p = &response[MS_CHAP2_PEER_CHALLENGE];
     int i;
+    LWIP_UNUSED_ARG(authenticator);
 
     BZERO(response, MS_CHAP2_RESPONSE_LEN);
 
diff --git a/src/netif/ppp/eap.c b/src/netif/ppp/eap.c
index 4c385d6f..2bb0c5e8 100644
--- a/src/netif/ppp/eap.c
+++ b/src/netif/ppp/eap.c
@@ -2046,6 +2046,8 @@ static void eap_response(ppp_pcb *pcb, u_char *inp, int id, int len) {
  * eap_success - Receive EAP Success message (client mode).
  */
 static void eap_success(ppp_pcb *pcb, u_char *inp, int id, int len) {
+	LWIP_UNUSED_ARG(id);
+
 	if (pcb->eap.es_client.ea_state != eapOpen && !eap_client_active(pcb)) {
 		ppp_dbglog("EAP unexpected success message in state %s (%d)",
 		    eap_state_name(pcb->eap.es_client.ea_state),
@@ -2070,6 +2072,8 @@ static void eap_success(ppp_pcb *pcb, u_char *inp, int id, int len) {
  * eap_failure - Receive EAP Failure message (client mode).
  */
 static void eap_failure(ppp_pcb *pcb, u_char *inp, int id, int len) {
+	LWIP_UNUSED_ARG(id);
+
 	if (!eap_client_active(pcb)) {
 		ppp_dbglog("EAP unexpected failure message in state %s (%d)",
 		    eap_state_name(pcb->eap.es_client.ea_state),
@@ -2173,7 +2177,7 @@ static int eap_printpkt(u_char *inp, int inlen, void (*printer) (void *, char *,
 	if (len < EAP_HEADERLEN || len > inlen)
 		return (0);
 
-	if (code >= 1 && code <= sizeof(eap_codenames) / sizeof(char *))
+	if (code >= 1 && code <= (int)sizeof(eap_codenames) / (int)sizeof(char *))
 		printer(arg, " %s", eap_codenames[code-1]);
 	else
 		printer(arg, " code=0x%x", code);
@@ -2188,7 +2192,7 @@ static int eap_printpkt(u_char *inp, int inlen, void (*printer) (void *, char *,
 		GETCHAR(rtype, inp);
 		len--;
 		if (rtype >= 1 &&
-		    rtype <= sizeof (eap_typenames) / sizeof (char *))
+		    rtype <= (int)sizeof (eap_typenames) / (int)sizeof (char *))
 			printer(arg, " %s", eap_typenames[rtype-1]);
 		else
 			printer(arg, " type=0x%x", rtype);
@@ -2283,7 +2287,7 @@ static int eap_printpkt(u_char *inp, int inlen, void (*printer) (void *, char *,
 				break;
 
 			case EAPSRP_SVALIDATOR:
-				if (len < sizeof (u32_t))
+				if (len < (int)sizeof (u32_t))
 					break;
 				GETLONG(uval, inp);
 				len -= sizeof (u32_t);
@@ -2323,7 +2327,7 @@ static int eap_printpkt(u_char *inp, int inlen, void (*printer) (void *, char *,
 		GETCHAR(rtype, inp);
 		len--;
 		if (rtype >= 1 &&
-		    rtype <= sizeof (eap_typenames) / sizeof (char *))
+		    rtype <= (int)sizeof (eap_typenames) / (int)sizeof (char *))
 			printer(arg, " %s", eap_typenames[rtype-1]);
 		else
 			printer(arg, " type=0x%x", rtype);
@@ -2347,7 +2351,7 @@ static int eap_printpkt(u_char *inp, int inlen, void (*printer) (void *, char *,
 			len--;
 			printer(arg, " <Suggested-type %02X", rtype);
 			if (rtype >= 1 &&
-			    rtype < sizeof (eap_typenames) / sizeof (char *))
+			    rtype < (int)sizeof (eap_typenames) / (int)sizeof (char *))
 				printer(arg, " (%s)", eap_typenames[rtype-1]);
 			printer(arg, ">");
 			break;
@@ -2389,7 +2393,7 @@ static int eap_printpkt(u_char *inp, int inlen, void (*printer) (void *, char *,
 				break;
 
 			case EAPSRP_CVALIDATOR:
-				if (len < sizeof (u32_t))
+				if (len < (int)sizeof (u32_t))
 					break;
 				GETLONG(uval, inp);
 				len -= sizeof (u32_t);
diff --git a/src/netif/ppp/ipcp.c b/src/netif/ppp/ipcp.c
index 1944fc86..8a0c87ac 100644
--- a/src/netif/ppp/ipcp.c
+++ b/src/netif/ppp/ipcp.c
@@ -2041,6 +2041,7 @@ static void ipcp_down(fsm *f) {
  * proxy arp entries, etc.
  */
 static void ipcp_clear_addrs(ppp_pcb *pcb, u32_t ouraddr, u32_t hisaddr, u8_t replacedefaultroute) {
+    LWIP_UNUSED_ARG(replacedefaultroute);
 
     if (pcb->proxy_arp_set) {
 	cifproxyarp(pcb, hisaddr);
@@ -2113,7 +2114,7 @@ static int ipcp_printpkt(u_char *p, int plen,
     if (len < HEADERLEN || len > plen)
 	return 0;
 
-    if (code >= 1 && code <= sizeof(ipcp_codenames) / sizeof(char *))
+    if (code >= 1 && code <= (int)sizeof(ipcp_codenames) / (int)sizeof(char *))
 	printer(arg, " %s", ipcp_codenames[code-1]);
     else
 	printer(arg, " code=0x%x", code);
diff --git a/src/netif/ppp/ipv6cp.c b/src/netif/ppp/ipv6cp.c
index 8fb01ada..ca511315 100644
--- a/src/netif/ppp/ipv6cp.c
+++ b/src/netif/ppp/ipv6cp.c
@@ -44,30 +44,30 @@
     Alain.Durand@imag.fr, IMAG,
     Jean-Luc.Richier@imag.fr, IMAG-LSR.
 
-    Ce travail a été fait au sein du GIE DYADE (Groupement d'Intérêt
-    Économique ayant pour membres BULL S.A. et l'INRIA).
+    Ce travail a �t� fait au sein du GIE DYADE (Groupement d'Int�r�t
+    �conomique ayant pour membres BULL S.A. et l'INRIA).
 
     Ce logiciel informatique est disponible aux conditions
-    usuelles dans la recherche, c'est-à-dire qu'il peut
-    être utilisé, copié, modifié, distribué à l'unique
-    condition que ce texte soit conservé afin que
+    usuelles dans la recherche, c'est-�-dire qu'il peut
+    �tre utilis�, copi�, modifi�, distribu� � l'unique
+    condition que ce texte soit conserv� afin que
     l'origine de ce logiciel soit reconnue.
 
     Le nom de l'Institut National de Recherche en Informatique
     et en Automatique (INRIA), de l'IMAG, ou d'une personne morale
-    ou physique ayant participé à l'élaboration de ce logiciel ne peut
-    être utilisé sans son accord préalable explicite.
+    ou physique ayant particip� � l'�laboration de ce logiciel ne peut
+    �tre utilis� sans son accord pr�alable explicite.
 
     Ce logiciel est fourni tel quel sans aucune garantie,
-    support ou responsabilité d'aucune sorte.
-    Ce logiciel est dérivé de sources d'origine
+    support ou responsabilit� d'aucune sorte.
+    Ce logiciel est d�riv� de sources d'origine
     "University of California at Berkeley" et
     "Digital Equipment Corporation" couvertes par des copyrights.
 
-    L'Institut d'Informatique et de Mathématiques Appliquées de Grenoble (IMAG)
-    est une fédération d'unités mixtes de recherche du CNRS, de l'Institut National
-    Polytechnique de Grenoble et de l'Université Joseph Fourier regroupant
-    sept laboratoires dont le laboratoire Logiciels, Systèmes, Réseaux (LSR).
+    L'Institut d'Informatique et de Math�matiques Appliqu�es de Grenoble (IMAG)
+    est une f�d�ration d'unit�s mixtes de recherche du CNRS, de l'Institut National
+    Polytechnique de Grenoble et de l'Universit� Joseph Fourier regroupant
+    sept laboratoires dont le laboratoire Logiciels, Syst�mes, R�seaux (LSR).
 
     This work has been done in the context of GIE DYADE (joint R & D venture
     between BULL S.A. and INRIA).
@@ -1396,7 +1396,7 @@ static int ipv6cp_printpkt(u_char *p, int plen,
     if (len < HEADERLEN || len > plen)
 	return 0;
 
-    if (code >= 1 && code <= sizeof(ipv6cp_codenames) / sizeof(char *))
+    if (code >= 1 && code <= (int)sizeof(ipv6cp_codenames) / (int)sizeof(char *))
 	printer(arg, " %s", ipv6cp_codenames[code-1]);
     else
 	printer(arg, " code=0x%x", code);
diff --git a/src/netif/ppp/lcp.c b/src/netif/ppp/lcp.c
index 52f7a50f..bd616c40 100644
--- a/src/netif/ppp/lcp.c
+++ b/src/netif/ppp/lcp.c
@@ -1382,6 +1382,8 @@ static int lcp_nakci(fsm *f, u_char *p, int len, int treat_as_reject) {
 		       try_.mrru = cishort;
 		   );
     }
+#else /* HAVE_MULTILINK */
+    LWIP_UNUSED_ARG(treat_as_reject);
 #endif /* HAVE_MULTILINK */
 
     /*
@@ -2332,7 +2334,7 @@ static int lcp_printpkt(u_char *p, int plen,
     if (len < HEADERLEN || len > plen)
 	return 0;
 
-    if (code >= 1 && code <= sizeof(lcp_codenames) / sizeof(char *))
+   if (code >= 1 && code <= (int)sizeof(lcp_codenames) / (int)sizeof(char *))
 	printer(arg, " %s", lcp_codenames[code-1]);
     else
 	printer(arg, " code=0x%x", code);
@@ -2617,6 +2619,7 @@ static void lcp_received_echo_reply(fsm *f, int id, u_char *inp, int len) {
     ppp_pcb *pcb = f->pcb;
     lcp_options *go = &pcb->lcp_gotoptions;
     u32_t magic;
+    LWIP_UNUSED_ARG(id);
 
     /* Check the magic number - don't count replies from ourselves. */
     if (len < 4) {
diff --git a/src/netif/ppp/ppp.c b/src/netif/ppp/ppp.c
index 615c41c4..09d39b73 100644
--- a/src/netif/ppp/ppp.c
+++ b/src/netif/ppp/ppp.c
@@ -1925,6 +1925,7 @@ static void ppp_over_l2tp_open(ppp_pcb *pcb) {
 #endif /* PPPOL2TP_SUPPORT */
 
 void ppp_link_down(ppp_pcb *pcb) {
+  LWIP_UNUSED_ARG(pcb); /* necessary if PPPDEBUG is defined to an empty function */
   PPPDEBUG(LOG_DEBUG, ("ppp_link_down: unit %d\n", pcb->num));
 }
 
@@ -2009,6 +2010,7 @@ int ppp_send_config(ppp_pcb *pcb, int mtu, u32_t accm, int pcomp, int accomp) {
 #if PPPOS_SUPPORT
   int i;
 #endif /* PPPOS_SUPPORT */
+  LWIP_UNUSED_ARG(mtu);
 
   /* pcb->mtu = mtu; -- set correctly with netif_set_mtu */
   pcb->pcomp = pcomp;
diff --git a/src/netif/ppp/pppoe.c b/src/netif/ppp/pppoe.c
index a5f4bd30..101ac90e 100644
--- a/src/netif/ppp/pppoe.c
+++ b/src/netif/ppp/pppoe.c
@@ -313,7 +313,7 @@ pppoe_disc_input(struct netif *netif, struct pbuf *pb)
   hunique_len = 0;
 #endif
   session = 0;
-  if (pb->len - off < PPPOE_HEADERLEN) {
+  if (pb->len - off < (u16_t)PPPOE_HEADERLEN) {
     PPPDEBUG(LOG_DEBUG, ("pppoe: packet too short: %d\n", pb->len));
     goto done;
   }
diff --git a/src/netif/ppp/pppol2tp.c b/src/netif/ppp/pppol2tp.c
index dad340aa..017223b4 100644
--- a/src/netif/ppp/pppol2tp.c
+++ b/src/netif/ppp/pppol2tp.c
@@ -189,6 +189,7 @@ static void pppol2tp_input(void *arg, struct udp_pcb *pcb, struct pbuf *p, struc
   pppol2tp_pcb *l2tp = (pppol2tp_pcb*)arg;
   u16_t hflags, hlen, len=0, tunnel_id=0, session_id=0, ns=0, nr=0, offset=0;
   u8_t *inp;
+  LWIP_UNUSED_ARG(pcb);
 
   if (l2tp->phase < PPPOL2TP_STATE_SCCRQ_SENT) {
     goto free_and_return;
@@ -324,6 +325,10 @@ static void pppol2tp_dispatch_control_packet(pppol2tp_pcb *l2tp, struct ip_addr
   u8_t md5_hash[16];
   u8_t challenge_id = 0;
 #endif /* PPPOL2TP_AUTH_SUPPORT */
+  LWIP_UNUSED_ARG(addr);
+  LWIP_UNUSED_ARG(len);
+  LWIP_UNUSED_ARG(tunnel_id);
+  LWIP_UNUSED_ARG(session_id);
 
   l2tp->peer_nr = nr;
   l2tp->peer_ns = ns;
diff --git a/src/netif/ppp/upap.c b/src/netif/ppp/upap.c
index 11dddd3e..72931305 100644
--- a/src/netif/ppp/upap.c
+++ b/src/netif/ppp/upap.c
@@ -357,7 +357,10 @@ static void upap_input(ppp_pcb *pcb, u_char *inpacket, int l) {
  */
 static void upap_rauthreq(ppp_pcb *pcb, u_char *inp, int id, int len) {
     u_char ruserlen, rpasswdlen;
-    char *ruser, *rpasswd;
+    char *ruser;
+#if 0
+    char *rpasswd;
+#endif
     char rhostname[256];
     int retcode;
     char *msg;
@@ -401,12 +404,12 @@ static void upap_rauthreq(ppp_pcb *pcb, u_char *inp, int id, int len) {
     }
 
     /* FIXME: we need a way to check peer secret */
+#if 0
     rpasswd = (char *) inp;
 
     /*
      * Check the username and password given.
      */
-#if 0
     retcode = check_passwd(pcb->upap.us_unit, ruser, ruserlen, rpasswd,
 			   rpasswdlen, &msg);
     BZERO(rpasswd, rpasswdlen);
@@ -423,11 +426,17 @@ static void upap_rauthreq(ppp_pcb *pcb, u_char *inp, int id, int len) {
 	    warn("calling number %q is not authorized", remote_number);
 	}
     }
-#endif
 
     msglen = strlen(msg);
     if (msglen > 255)
 	msglen = 255;
+#else
+    /* only here to clean compiler warnings */
+    retcode = UPAP_AUTHNAK;
+    msg = NULL;
+    msglen = 0;
+#endif /* 0 */
+
     upap_sresp(pcb, retcode, id, msg, msglen);
 
     /* Null terminate and clean remote name. */
@@ -454,6 +463,7 @@ static void upap_rauthreq(ppp_pcb *pcb, u_char *inp, int id, int len) {
 static void upap_rauthack(ppp_pcb *pcb, u_char *inp, int id, int len) {
     u_char msglen;
     char *msg;
+    LWIP_UNUSED_ARG(id);
 
     if (pcb->upap.us_clientstate != UPAPCS_AUTHREQ) /* XXX */
 	return;
@@ -488,6 +498,7 @@ static void upap_rauthack(ppp_pcb *pcb, u_char *inp, int id, int len) {
 static void upap_rauthnak(ppp_pcb *pcb, u_char *inp, int id, int len) {
     u_char msglen;
     char *msg;
+    LWIP_UNUSED_ARG(id);
 
     if (pcb->upap.us_clientstate != UPAPCS_AUTHREQ) /* XXX */
 	return;
@@ -608,7 +619,7 @@ static int upap_printpkt(u_char *p, int plen, void (*printer) (void *, char *, .
     if (len < UPAP_HEADERLEN || len > plen)
 	return 0;
 
-    if (code >= 1 && code <= sizeof(upap_codenames) / sizeof(char *))
+    if (code >= 1 && code <= (int)sizeof(upap_codenames) / (int)sizeof(char *))
 	printer(arg, " %s", upap_codenames[code-1]);
     else
 	printer(arg, " code=0x%x", code);
diff --git a/src/netif/ppp/utils.c b/src/netif/ppp/utils.c
index d03f6c25..60cf7f85 100644
--- a/src/netif/ppp/utils.c
+++ b/src/netif/ppp/utils.c
@@ -209,7 +209,7 @@ int ppp_vslprintf(char *buf, int buflen, char *fmt, va_list args) {
 		val = va_arg(args, long);
 		if ((long)val < 0) {
 		    neg = 1;
-		    val = -val;
+		    val = (unsigned long)-val;
 		}
 		base = 10;
 		break;
@@ -607,6 +607,8 @@ static void ppp_logit(int level, char *fmt, va_list args) {
 }
 
 static void ppp_log_write(int level, char *buf) {
+    LWIP_UNUSED_ARG(level); /* necessary if PPPDEBUG is defined to an empty function */
+    LWIP_UNUSED_ARG(buf);
     PPPDEBUG(level, ("%s\n", buf) );
 #if 0
     if (log_to_fd >= 0 && (level != LOG_DEBUG || debug)) {