diff --git a/slirp/bootp.c b/slirp/bootp.c
index b7db9fa..1baaab1 100644
--- a/slirp/bootp.c
+++ b/slirp/bootp.c
@@ -23,6 +23,12 @@
  */
 #include <slirp.h>
 
+#if defined(_WIN32)
+/* Windows ntohl() returns an u_long value.
+ * Add a type cast to match the format strings. */
+# define ntohl(n) ((uint32_t)ntohl(n))
+#endif
+
 /* XXX: only DHCP is supported */
 
 #define LEASE_TIME (24 * 3600)
@@ -155,7 +161,7 @@
     dhcp_decode(bp, &dhcp_msg_type, &preq_addr);
     DPRINTF("bootp packet op=%d msgtype=%d", bp->bp_op, dhcp_msg_type);
     if (preq_addr.s_addr != htonl(0L))
-        DPRINTF(" req_addr=%08x\n", ntohl(preq_addr.s_addr));
+        DPRINTF(" req_addr=%08" PRIx32 "\n", ntohl(preq_addr.s_addr));
     else
         DPRINTF("\n");
 
@@ -234,7 +240,7 @@
     q += 4;
 
     if (bc) {
-        DPRINTF("%s addr=%08x\n",
+        DPRINTF("%s addr=%08" PRIx32 "\n",
                 (dhcp_msg_type == DHCPDISCOVER) ? "offered" : "ack'ed",
                 ntohl(daddr.sin_addr.s_addr));
 
@@ -302,7 +308,7 @@
     } else {
         static const char nak_msg[] = "requested address not available";
 
-        DPRINTF("nak'ed addr=%08x\n", ntohl(preq_addr.s_addr));
+        DPRINTF("nak'ed addr=%08" PRIx32 "\n", ntohl(preq_addr.s_addr));
 
         *q++ = RFC2132_MSG_TYPE;
         *q++ = 1;
diff --git a/slirp/if.c b/slirp/if.c
index fb7acf8..8325a2a 100644
--- a/slirp/if.c
+++ b/slirp/if.c
@@ -53,8 +53,8 @@
 	int on_fastq = 1;
 
 	DEBUG_CALL("if_output");
-	DEBUG_ARG("so = %lx", (long)so);
-	DEBUG_ARG("ifm = %lx", (long)ifm);
+	DEBUG_ARG("so = %p", so);
+	DEBUG_ARG("ifm = %p", ifm);
 
 	/*
 	 * First remove the mbuf from m_usedlist,
diff --git a/slirp/ip_icmp.c b/slirp/ip_icmp.c
index 9f1cb08..23b9f0f 100644
--- a/slirp/ip_icmp.c
+++ b/slirp/ip_icmp.c
@@ -125,7 +125,7 @@
   Slirp *slirp = m->slirp;
 
   DEBUG_CALL("icmp_input");
-  DEBUG_ARG("m = %lx", (long )m);
+  DEBUG_ARG("m = %p", m);
   DEBUG_ARG("m_len = %d", m->m_len);
 
   /*
@@ -252,7 +252,7 @@
   register struct mbuf *m;
 
   DEBUG_CALL("icmp_error");
-  DEBUG_ARG("msrc = %lx", (long )msrc);
+  DEBUG_ARG("msrc = %p", msrc);
   DEBUG_ARG("msrc_len = %d", msrc->m_len);
 
   if(type!=ICMP_UNREACH && type!=ICMP_TIMXCEED) goto end_error;
diff --git a/slirp/ip_input.c b/slirp/ip_input.c
index 880bdfd..7d436e6 100644
--- a/slirp/ip_input.c
+++ b/slirp/ip_input.c
@@ -80,7 +80,7 @@
 	int hlen;
 
 	DEBUG_CALL("ip_input");
-	DEBUG_ARG("m = %lx", (long)m);
+	DEBUG_ARG("m = %p", m);
 	DEBUG_ARG("m_len = %d", m->m_len);
 
 	if (m->m_len < sizeof (struct ip)) {
@@ -232,9 +232,9 @@
 	int i, next;
 
 	DEBUG_CALL("ip_reass");
-	DEBUG_ARG("ip = %lx", (long)ip);
-	DEBUG_ARG("fp = %lx", (long)fp);
-	DEBUG_ARG("m = %lx", (long)m);
+	DEBUG_ARG("ip = %p", ip);
+	DEBUG_ARG("fp = %p", fp);
+	DEBUG_ARG("m = %p", m);
 
 	/*
 	 * Presence of header sizes in mbufs
@@ -400,7 +400,7 @@
 ip_enq(register struct ipasfrag *p, register struct ipasfrag *prev)
 {
 	DEBUG_CALL("ip_enq");
-	DEBUG_ARG("prev = %lx", (long)prev);
+	DEBUG_ARG("prev = %p", prev);
 	p->ipf_prev =  prev;
 	p->ipf_next = prev->ipf_next;
 	((struct ipasfrag *)(prev->ipf_next))->ipf_prev = p;
diff --git a/slirp/ip_output.c b/slirp/ip_output.c
index c82830f..1254d0d 100644
--- a/slirp/ip_output.c
+++ b/slirp/ip_output.c
@@ -60,8 +60,8 @@
 	int len, off, error = 0;
 
 	DEBUG_CALL("ip_output");
-	DEBUG_ARG("so = %lx", (long)so);
-	DEBUG_ARG("m0 = %lx", (long)m0);
+	DEBUG_ARG("so = %p", so);
+	DEBUG_ARG("m0 = %p", m0);
 
 	ip = mtod(m, struct ip *);
 	/*
diff --git a/slirp/mbuf.c b/slirp/mbuf.c
index 4fefb04..795fc29 100644
--- a/slirp/mbuf.c
+++ b/slirp/mbuf.c
@@ -94,7 +94,7 @@
         m->arp_requested = false;
         m->expiration_date = (uint64_t)-1;
 end_error:
-	DEBUG_ARG("m = %lx", (long )m);
+	DEBUG_ARG("m = %p", m);
 	return m;
 }
 
@@ -103,7 +103,7 @@
 {
 
   DEBUG_CALL("m_free");
-  DEBUG_ARG("m = %lx", (long )m);
+  DEBUG_ARG("m = %p", m);
 
   if(m) {
 	/* Remove from m_usedlist */
@@ -221,7 +221,7 @@
 	struct mbuf *m;
 
 	DEBUG_CALL("dtom");
-	DEBUG_ARG("dat = %lx", (long )dat);
+	DEBUG_ARG("dat = %p", dat);
 
 	/* bug corrected for M_EXT buffers */
 	for (m = slirp->m_usedlist.m_next; m != &slirp->m_usedlist;
diff --git a/slirp/misc.c b/slirp/misc.c
index 578e8b2..5497161 100644
--- a/slirp/misc.c
+++ b/slirp/misc.c
@@ -123,9 +123,9 @@
 	pid_t pid;
 
 	DEBUG_CALL("fork_exec");
-	DEBUG_ARG("so = %lx", (long)so);
-	DEBUG_ARG("ex = %lx", (long)ex);
-	DEBUG_ARG("do_pty = %lx", (long)do_pty);
+	DEBUG_ARG("so = %p", so);
+	DEBUG_ARG("ex = %p", ex);
+	DEBUG_ARG("do_pty = %x", do_pty);
 
 	if (do_pty == 2) {
                 return 0;
diff --git a/slirp/sbuf.c b/slirp/sbuf.c
index 08ec2b4..b8c3db7 100644
--- a/slirp/sbuf.c
+++ b/slirp/sbuf.c
@@ -72,8 +72,8 @@
 	int ret = 0;
 
 	DEBUG_CALL("sbappend");
-	DEBUG_ARG("so = %lx", (long)so);
-	DEBUG_ARG("m = %lx", (long)m);
+	DEBUG_ARG("so = %p", so);
+	DEBUG_ARG("m = %p", m);
 	DEBUG_ARG("m->m_len = %d", m->m_len);
 
 	/* Shouldn't happen, but...  e.g. foreign host closes connection */
diff --git a/slirp/socket.c b/slirp/socket.c
index 37ac5cf..1673e3a 100644
--- a/slirp/socket.c
+++ b/slirp/socket.c
@@ -91,7 +91,7 @@
 	int mss = so->so_tcpcb->t_maxseg;
 
 	DEBUG_CALL("sopreprbuf");
-	DEBUG_ARG("so = %lx", (long )so);
+	DEBUG_ARG("so = %p", so);
 
 	if (len <= 0)
 		return 0;
@@ -155,7 +155,7 @@
 	struct iovec iov[2];
 
 	DEBUG_CALL("soread");
-	DEBUG_ARG("so = %lx", (long )so);
+	DEBUG_ARG("so = %p", so);
 
 	/*
 	 * No need to check if there's enough room to read.
@@ -215,7 +215,7 @@
 	struct iovec iov[2];
 
 	DEBUG_CALL("soreadbuf");
-	DEBUG_ARG("so = %lx", (long )so);
+	DEBUG_ARG("so = %p", so);
 
 	/*
 	 * No need to check if there's enough room to read.
@@ -263,7 +263,7 @@
 	struct tcpcb *tp = sototcpcb(so);
 
 	DEBUG_CALL("sorecvoob");
-	DEBUG_ARG("so = %lx", (long)so);
+	DEBUG_ARG("so = %p", so);
 
 	/*
 	 * We take a guess at how much urgent data has arrived.
@@ -293,7 +293,7 @@
 	int n, len;
 
 	DEBUG_CALL("sosendoob");
-	DEBUG_ARG("so = %lx", (long)so);
+	DEBUG_ARG("so = %p", so);
 	DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);
 
 	if (so->so_urgc > 2048)
@@ -351,7 +351,7 @@
 	struct iovec iov[2];
 
 	DEBUG_CALL("sowrite");
-	DEBUG_ARG("so = %lx", (long)so);
+	DEBUG_ARG("so = %p", so);
 
 	if (so->so_urgc) {
 		sosendoob(so);
@@ -441,7 +441,7 @@
 	socklen_t addrlen = sizeof(struct sockaddr_in);
 
 	DEBUG_CALL("sorecvfrom");
-	DEBUG_ARG("so = %lx", (long)so);
+	DEBUG_ARG("so = %p", so);
 
 	if (so->so_type == IPPROTO_ICMP) {   /* This is a "ping" reply */
 	  char buff[256];
@@ -543,8 +543,8 @@
 	struct sockaddr_in addr;
 
 	DEBUG_CALL("sosendto");
-	DEBUG_ARG("so = %lx", (long)so);
-	DEBUG_ARG("m = %lx", (long)m);
+	DEBUG_ARG("so = %p", so);
+	DEBUG_ARG("m = %p", m);
 
         addr.sin_family = AF_INET;
 	if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) ==
diff --git a/slirp/tcp_input.c b/slirp/tcp_input.c
index 00a77b4..6b096ec 100644
--- a/slirp/tcp_input.c
+++ b/slirp/tcp_input.c
@@ -231,8 +231,8 @@
     Slirp *slirp;
 
 	DEBUG_CALL("tcp_input");
-	DEBUG_ARGS((dfd, " m = %8lx  iphlen = %2d  inso = %lx\n",
-		    (long )m, iphlen, (long )inso ));
+	DEBUG_ARGS((dfd, " m = %p  iphlen = %2d  inso = %p\n",
+		    m, iphlen, inso));
 
 	/*
 	 * If called with m == 0, then we're continuing the connect
@@ -923,8 +923,8 @@
 
 		if (SEQ_LEQ(ti->ti_ack, tp->snd_una)) {
 			if (ti->ti_len == 0 && tiwin == tp->snd_wnd) {
-			  DEBUG_MISC((dfd, " dup ack  m = %lx  so = %lx\n",
-				      (long )m, (long )so));
+			  DEBUG_MISC((dfd, " dup ack  m = %p  so = %p\n",
+				      m, so));
 				/*
 				 * If we have outstanding data (other than
 				 * a window probe), this is a completely
@@ -1302,7 +1302,7 @@
 	int opt, optlen;
 
 	DEBUG_CALL("tcp_dooptions");
-	DEBUG_ARGS((dfd, " tp = %lx  cnt=%i\n", (long)tp, cnt));
+	DEBUG_ARGS((dfd, " tp = %p  cnt=%i\n", tp, cnt));
 
 	for (; cnt > 0; cnt -= optlen, cp += optlen) {
 		opt = cp[0];
@@ -1383,7 +1383,7 @@
 	register short delta;
 
 	DEBUG_CALL("tcp_xmit_timer");
-	DEBUG_ARG("tp = %lx", (long)tp);
+	DEBUG_ARG("tp = %p", tp);
 	DEBUG_ARG("rtt = %d", rtt);
 
 	if (tp->t_srtt != 0) {
@@ -1471,7 +1471,7 @@
 	int mss;
 
 	DEBUG_CALL("tcp_mss");
-	DEBUG_ARG("tp = %lx", (long)tp);
+	DEBUG_ARG("tp = %p", tp);
 	DEBUG_ARG("offer = %d", offer);
 
 	mss = min(IF_MTU, IF_MRU) - sizeof(struct tcpiphdr);
diff --git a/slirp/tcp_output.c b/slirp/tcp_output.c
index 8aa3d90..fafca58 100644
--- a/slirp/tcp_output.c
+++ b/slirp/tcp_output.c
@@ -66,7 +66,7 @@
 	int idle, sendalot;
 
 	DEBUG_CALL("tcp_output");
-	DEBUG_ARG("tp = %lx", (long )tp);
+	DEBUG_ARG("tp = %p", tp);
 
 	/*
 	 * Determine length of data that should be transmitted,
diff --git a/slirp/tcp_subr.c b/slirp/tcp_subr.c
index 7571c5a..e161ed2 100644
--- a/slirp/tcp_subr.c
+++ b/slirp/tcp_subr.c
@@ -224,7 +224,7 @@
 struct tcpcb *tcp_drop(struct tcpcb *tp, int err)
 {
 	DEBUG_CALL("tcp_drop");
-	DEBUG_ARG("tp = %lx", (long)tp);
+	DEBUG_ARG("tp = %p", tp);
 	DEBUG_ARG("errno = %d", errno);
 
 	if (TCPS_HAVERCVDSYN(tp->t_state)) {
@@ -249,7 +249,7 @@
 	register struct mbuf *m;
 
 	DEBUG_CALL("tcp_close");
-	DEBUG_ARG("tp = %lx", (long )tp);
+	DEBUG_ARG("tp = %p", tp);
 
 	/* free the reassembly queue, if any */
 	t = tcpfrag_list_first(tp);
@@ -290,7 +290,7 @@
 {
 
 	DEBUG_CALL("tcp_sockclosed");
-	DEBUG_ARG("tp = %lx", (long)tp);
+	DEBUG_ARG("tp = %p", tp);
 
 	switch (tp->t_state) {
 
@@ -330,7 +330,7 @@
   int ret=0;
 
   DEBUG_CALL("tcp_fconnect");
-  DEBUG_ARG("so = %lx", (long )so);
+  DEBUG_ARG("so = %p", so);
 
   if( (ret = so->s = qemu_socket(AF_INET,SOCK_STREAM,0)) >= 0) {
     int opt, s=so->s;
@@ -393,7 +393,7 @@
     int s, opt;
 
     DEBUG_CALL("tcp_connect");
-    DEBUG_ARG("inso = %lx", (long)inso);
+    DEBUG_ARG("inso = %p", inso);
 
     /*
      * If it's an SS_ACCEPTONCE socket, no need to socreate()
@@ -564,8 +564,8 @@
 	char *bptr;
 
 	DEBUG_CALL("tcp_emu");
-	DEBUG_ARG("so = %lx", (long)so);
-	DEBUG_ARG("m = %lx", (long)m);
+	DEBUG_ARG("so = %p", so);
+	DEBUG_ARG("m = %p", m);
 
 	switch(so->so_emu) {
 		int x, i;
@@ -900,7 +900,7 @@
     int do_pty;
 
     DEBUG_CALL("tcp_ctl");
-    DEBUG_ARG("so = %lx", (long )so);
+    DEBUG_ARG("so = %p", so);
 
     if (so->so_faddr.s_addr != slirp->vhost_addr.s_addr) {
         /* Check if it's pty_exec */
diff --git a/slirp/udp.c b/slirp/udp.c
index f77e00f..fee13b4 100644
--- a/slirp/udp.c
+++ b/slirp/udp.c
@@ -72,7 +72,7 @@
 	struct socket *so;
 
 	DEBUG_CALL("udp_input");
-	DEBUG_ARG("m = %lx", (long)m);
+	DEBUG_ARG("m = %p", m);
 	DEBUG_ARG("iphlen = %d", iphlen);
 
 	/*
@@ -241,8 +241,8 @@
 	int error = 0;
 
 	DEBUG_CALL("udp_output");
-	DEBUG_ARG("so = %lx", (long)so);
-	DEBUG_ARG("m = %lx", (long)m);
+	DEBUG_ARG("so = %p", so);
+	DEBUG_ARG("m = %p", m);
 	DEBUG_ARG("saddr = %lx", (long)saddr->sin_addr.s_addr);
 	DEBUG_ARG("daddr = %lx", (long)daddr->sin_addr.s_addr);