From 575ca4aa721f4aa5295064dd36912535ce64701e Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sat, 11 Jul 1992 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1992-07-11

---
 gnot/bbmalloc.c   |  3 ++-
 gnot/clock.c      |  1 -
 gnot/devduart.c   |  4 ++++
 gnot/devhifi.c    |  7 +++++--
 gnot/devincon.c   |  9 ++++++---
 gnot/devisdn.c    |  3 +++
 gnot/devport.c    |  2 ++
 gnot/main.c       |  7 ++++---
 gnot/mmu.c        |  5 ++---
 gnot/screen.c     |  3 +++
 gnot/trap.c       |  1 -
 pc/devether.c     |  8 ++++++++
 pc/devfloppy.c    | 17 +++++++----------
 pc/devhard.c      | 11 ++++++++---
 pc/devincon.c     |  7 ++++++-
 pc/devlpt.c       |  8 +++++++-
 pc/devrtc.c       | 11 +++++------
 pc/devuart.c      | 12 +++++++++---
 pc/devvga.c       |  9 ++++++---
 pc/dma.c          |  2 --
 pc/kbd.c          |  7 +++----
 pc/main.c         |  9 ++++-----
 pc/mmu.c          |  4 ----
 pc/pmu.c          |  1 +
 pc/segment.h      |  6 +++---
 pc/vga.c          | 11 +++++++----
 port/alarm.c      |  1 -
 port/chan.c       |  8 +++-----
 port/dev.c        |  1 +
 port/devarp.c     |  9 +++++++--
 port/devbit.c     | 15 +++++++--------
 port/devboot.c    |  4 ++--
 port/devconc.c    |  9 ++++++---
 port/devcons.c    |  5 +----
 port/devdk.c      | 10 +++++-----
 port/devdup.c     |  4 ++++
 port/devenv.c     |  4 ++++
 port/devip.c      | 20 +++++++++++---------
 port/deviproute.c |  3 ++-
 port/devkprof.c   |  2 ++
 port/devlance.c   |  3 +--
 port/devmux.c     |  8 +++++---
 port/devpipe.c    |  4 +++-
 port/devproc.c    |  3 +--
 port/devroot.c    |  2 ++
 port/devscc.c     |  3 +--
 port/devscsi.c    |  6 ++++++
 port/devsrv.c     |  7 +++++--
 port/devwren.c    |  1 +
 port/fault.c      |  2 --
 port/ipdat.h      |  4 ++--
 port/net.c        |  1 +
 port/page.c       |  2 +-
 port/pgrp.c       |  2 +-
 port/portfns.h    |  2 +-
 port/proc.c       |  4 ----
 port/segment.c    |  2 +-
 port/stil.c       |  9 +++------
 port/stip.c       |  2 +-
 port/stlapd.c     |  8 ++------
 port/stream.c     | 17 +++++++++--------
 port/streboot.c   |  1 +
 port/stsplice.c   |  2 --
 port/sturp.c      | 29 ++++++++---------------------
 port/swap.c       |  6 +++---
 port/sysfile.c    |  9 ++-------
 port/sysproc.c    | 15 +++++----------
 port/tcpif.c      |  1 -
 port/tcpinput.c   |  5 +++--
 power/clock.c     |  1 -
 power/devcyc.c    |  4 +++-
 power/devduart.c  |  8 ++++++--
 power/devhs.c     |  7 ++++++-
 power/devrtc.c    |  5 ++++-
 power/main.c      | 11 +++--------
 power/trap.c      |  1 -
 ss/bbmalloc.c     |  2 --
 ss/clock.c        |  2 --
 ss/main.c         |  7 +------
 ss/mmu.c          |  9 ++-------
 ss/screen.c       | 11 ++++++++---
 81 files changed, 262 insertions(+), 229 deletions(-)

diff --git a/gnot/bbmalloc.c b/gnot/bbmalloc.c
index ba58450d3c6b74034541b129362ff24e067ce1c0..c1c06ac1bdf99e746aa9195aade72009d050d73a 100644
--- a/gnot/bbmalloc.c
+++ b/gnot/bbmalloc.c
@@ -53,7 +53,6 @@ bbmalloc(int nbytes)
 void
 bbfree(void *p, int n)
 {
-	ulong *up;
 	int a, s;
 
 	s = splhi();
@@ -66,12 +65,14 @@ bbfree(void *p, int n)
 void
 flushvirtpage(void *p)
 {
+	USED(p);
 	flushcpucache();
 }
 
 void
 bbdflush(void *p, int n)
 {
+	USED(p, n);
 	flushcpucache();
 }
 
diff --git a/gnot/clock.c b/gnot/clock.c
index 5f231b5e80859ae5efbe472ddd87f362b251cd4c..b04510b9fab22c5ae77274cddd037de8a5eb07f9 100644
--- a/gnot/clock.c
+++ b/gnot/clock.c
@@ -10,7 +10,6 @@
 void
 delay(int ms)
 {
-	ulong t, *p;
 	int i;
 
 	ms *= 1000;	/* experimentally determined */
diff --git a/gnot/devduart.c b/gnot/devduart.c
index 696ba8bcd89282644e56deac692e77e5a6271f69..d02f7b010a96962aae3349f160442e8cafa36a0b 100644
--- a/gnot/devduart.c
+++ b/gnot/devduart.c
@@ -709,6 +709,7 @@ duartopen(Chan *c, int omode)
 void
 duartcreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -742,17 +743,20 @@ duartread(Chan *c, void *buf, long n, ulong offset)
 long
 duartwrite(Chan *c, void *va, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, va, n, 0);
 }
 
 void
 duartremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void
 duartwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
diff --git a/gnot/devhifi.c b/gnot/devhifi.c
index d1819a3f15a0f63acd386a85ec4e6fd7eb2cd335..23fcfbe4f0203ddcfde22915dc2e9a9a6a43d75c 100644
--- a/gnot/devhifi.c
+++ b/gnot/devhifi.c
@@ -175,6 +175,7 @@ hifiopen(Chan *c, int omode)
 void	 
 hificreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -233,6 +234,7 @@ hifiwrite(Chan *c, void *buf, long n, ulong offset)
 	Hifichan *hp = &hifichan[c->dev];
 	char nbuf[32], *p;
 
+	USED(offset);
 	if(n < 0)
 		return 0;
 	switch(STREAMTYPE(c->qid.path)){
@@ -252,12 +254,14 @@ hifiwrite(Chan *c, void *buf, long n, ulong offset)
 void	 
 hifiremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void	 
 hifiwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
@@ -517,8 +521,7 @@ hifiintr(void)
 	Isdn *ip;
 	Hifichan *hp;
 	Hifi *hifi;
-	int intr = 0, status, n, c, wake = 0, w = 0;
-	uchar *p;
+	int intr = 0, status, wake = 0, w = 0;
 
 	for(hp=hifichan; hp<hifichanN; hp++){
 		if(!(ip = hp->udev))	/* assign = */
diff --git a/gnot/devincon.c b/gnot/devincon.c
index d31c344632c7e77b72db1df1d32ca09d60834ac2..456ff0fd6ba9042c3507bf91e8349a8545447a51 100644
--- a/gnot/devincon.c
+++ b/gnot/devincon.c
@@ -273,7 +273,6 @@ inconpoll(Incon *ip, int station)
 void
 inconrestart(Incon *ip)
 {
-	Device *dev;
 	int i;
 
 	if(!canqlock(&ip->reslock))
@@ -309,7 +308,6 @@ void
 inconreset(void)
 {
 	int i;
-	Incon *ip;
 
 	incon[0].dev = INCON;
 	incon[0].state = Selected;
@@ -387,6 +385,7 @@ inconopen(Chan *c, int omode)
 void	 
 inconcreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -417,18 +416,21 @@ inconread(Chan *c, void *buf, long n, ulong offset)
 long	 
 inconwrite(Chan *c, void *buf, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, buf, n, 0);
 }
 
 void	 
 inconremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void	 
 inconwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
@@ -669,7 +671,7 @@ static void
 inconkproc(void *arg)
 {
 	Incon *ip;
-	Block *bp, *nbp;
+	Block *bp;
 	int i;
 	int locked;
 
@@ -883,6 +885,7 @@ inconintr(Ureg *ur)
 	uchar status;
 	Incon *ip;
 
+	USED(ur);
 	ip = &incon[0];
 
 	status = ip->dev->status;
diff --git a/gnot/devisdn.c b/gnot/devisdn.c
index 2251d0ea168e972ad5b42158c2619c81e14b65be..47e9d1c4462b1cb63b9fe1cf379cf6897d976091 100644
--- a/gnot/devisdn.c
+++ b/gnot/devisdn.c
@@ -132,6 +132,7 @@ isdnopen(Chan *c, int omode)
 void	 
 isdncreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -245,12 +246,14 @@ isdnwrite(Chan *c, void *buf, long n, ulong offset)
 void	 
 isdnremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void	 
 isdnwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
diff --git a/gnot/devport.c b/gnot/devport.c
index b111c9b47a452b88fc911ac85f3a870b0708453c..4bca3c3b7f099234a88ca6118dc3ba3ee8be7b9a 100644
--- a/gnot/devport.c
+++ b/gnot/devport.c
@@ -123,12 +123,14 @@ portopen(Chan *c, int omode)
 void
 portcreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
 void
 portclose(Chan *c)
 {
+	USED(c);
 }
 
 long
diff --git a/gnot/main.c b/gnot/main.c
index e7219cbb27d2de7e0ce847e14b508ef5caf8071f..0f43bc3d78302ce263b04adae171c86706527781 100644
--- a/gnot/main.c
+++ b/gnot/main.c
@@ -104,7 +104,7 @@ machinit(void)
 void
 mmuinit(void)
 {
-	ulong l, d, i, scr;
+	ulong l, d, i;
 
 	/*
 	 * Invalidate user addresses
@@ -128,8 +128,6 @@ mmuinit(void)
 void
 init0(void)
 {
-	Chan *c;
-
 	u->nerrlab = 0;
 	m->proc = u->p;
 	u->p->state = Running;
@@ -353,6 +351,7 @@ procsave(Proc *p)
 {
 	Balu *balu = (Balu *)u->balusave;
 
+	USED(p);
 	fpsave(&u->fpsave);
 	if(u->fpsave.type){
 		if(u->fpsave.size > sizeof u->fpsave.junk)
@@ -397,9 +396,11 @@ procrestore(Proc *p)
 void
 buzz(int f, int d)
 {
+	USED(f, d);
 }
 
 void
 lights(int val)
 {
+	USED(val);
 }
diff --git a/gnot/mmu.c b/gnot/mmu.c
index 89c89bed19bcb84e6f7b2219764a906d5adf6649..1ae58e45455d5f572e5036476a5b4fd646717d1c 100644
--- a/gnot/mmu.c
+++ b/gnot/mmu.c
@@ -19,8 +19,6 @@ void
 mapstack(Proc *p)
 {
 	ulong tlbvirt, tlbphys;
-	ulong next;
-	MMU *mm, *mn, *me;
 
 
 	if(p->upage->va != (USERADDR|(p->pid&0xFFFF)) && p->pid != 0)
@@ -61,8 +59,9 @@ putkmmu(ulong tlbvirt, ulong tlbphys)
 }
 
 void
-putmmu(ulong tlbvirt, ulong tlbphys, Page *p)
+putmmu(ulong tlbvirt, ulong tlbphys, Page *pg)
 {
+	USED(pg);
 	if(tlbvirt&KZERO)
 		panic("putmmu");
 	tlbphys |= VTAG(tlbvirt)<<24;
diff --git a/gnot/screen.c b/gnot/screen.c
index 642deedfc9c37783a0daaa217adcd3c819579017..c59e1758f75717fc064e33922b676f8cf6acf3a8 100644
--- a/gnot/screen.c
+++ b/gnot/screen.c
@@ -135,18 +135,21 @@ getcolor(ulong p, ulong *pr, ulong *pg, ulong *pb)
 int
 setcolor(ulong p, ulong r, ulong g, ulong b)
 {
+	USED(p, r, g, b);
 	return 0;	/* can't change mono screen colormap */
 }
 
 int
 hwcursset(uchar *s, uchar *c, int ox, int oy)
 {
+	USED(s, c, ox, oy);
 	return 0;
 }
 
 int
 hwcursmove(int x, int y)
 {
+	USED(x, y);
 	return 0;
 }
 
diff --git a/gnot/trap.c b/gnot/trap.c
index 3b706ae8eac037fcadefa87f2ef9aa6f43de4469..2ceb895d4260dce01f3b407990c028f018a57117 100644
--- a/gnot/trap.c
+++ b/gnot/trap.c
@@ -273,7 +273,6 @@ noted(Ureg *ur, ulong arg0)
 long
 syscall(Ureg *aur)
 {
-	int i;
 	long ret;
 	ulong sp;
 	Ureg *ur;
diff --git a/pc/devether.c b/pc/devether.c
index 68f8d6f06c174ead05c1579159d26ed55777cbb2..967b73086e58b6e613f078eb8b209516dc9482ea 100644
--- a/pc/devether.c
+++ b/pc/devether.c
@@ -143,6 +143,7 @@ etheropen(Chan *c, int omode)
 void
 ethercreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -162,12 +163,14 @@ etherread(Chan *c, void *a, long n, ulong offset)
 long
 etherwrite(Chan *c, char *a, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, a, n, 0);
 }
 
 void
 etherremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
@@ -350,6 +353,7 @@ clonecon(Chan *c)
 	Ctlr *cp = &ctlr[0];
 	Type *tp;
 
+	USED(c);
 	for(tp = cp->type; tp < &cp->type[NType]; tp++){
 		qlock(tp);
 		if(tp->inuse || tp->q){
@@ -362,6 +366,7 @@ clonecon(Chan *c)
 		return tp - cp->type;
 	}
 	exhausted("ether channels");
+	return 0;
 }
 
 static void
@@ -370,6 +375,7 @@ statsfill(Chan *c, char *p, int n)
 	Ctlr *cp = &ctlr[0];
 	char buf[256];
 
+	USED(c);
 	sprint(buf, "in: %d\nout: %d\ncrc errs %d\noverflows: %d\nframe errs %d\nbuff errs: %d\noerrs %d\naddr: %.02x:%.02x:%.02x:%.02x:%.02x:%.02x\n",
 		cp->inpackets, cp->outpackets, cp->crcs,
 		cp->overflows, cp->frames, cp->buffs, cp->oerrs,
@@ -693,6 +699,7 @@ wd8013mode(Ctlr *cp, int on)
 static void
 wd8013online(Ctlr *cp, int on)
 {
+	USED(on);
 	OUT(cp->hw, w.tcr, 0);
 }
 
@@ -777,6 +784,7 @@ wd8013intr(Ureg *ur)
 	Buffer *tb;
 	uchar isr;
 
+	USED(ur);
 	while(isr = IN(hw, r.isr)){
 		OUT(hw, w.isr, isr);
 		if(isr & 0x08)			/* Txe - transmit error */
diff --git a/pc/devfloppy.c b/pc/devfloppy.c
index 8e21b0a1b5a8fdf92667330e51ff1e4c2053fc0b..5ed2e52ad29e540c7cdf330d87d1b219771c7368 100644
--- a/pc/devfloppy.c
+++ b/pc/devfloppy.c
@@ -196,9 +196,6 @@ floppyreset(void)
 {
 	Drive *dp;
 	Type *t;
-	int n;
-	ulong p;
-	long l;
 
 	/*
 	 *  init dependent parameters
@@ -290,23 +287,27 @@ floppyopen(Chan *c, int omode)
 void
 floppycreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
 void
 floppyclose(Chan *c)
 {
+	USED(c);
 }
 
 void
 floppyremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void
 floppywstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
@@ -351,7 +352,6 @@ floppyread(Chan *c, void *a, long n)
 	long rv, i;
 	int nn, sec, head, cyl;
 	long len;
-	long noff;
 	uchar *aa;
 
 	if(c->qid.path == CHDIR)
@@ -420,7 +420,6 @@ floppywrite(Chan *c, void *a, long n)
 	Drive *dp;
 	long rv, i;
 	char *aa = a;
-	int dev;
 
 	rv = 0;
 	dp = &fl.d[c->qid.path & ~Qmask];
@@ -474,6 +473,7 @@ floppykproc(void *a)
 {
 	Drive *dp;
 
+	USED(a);
 	while(waserror())
 		;
 	for(;;){
@@ -608,8 +608,6 @@ floppypos(Drive *dp, long off)
 	int lsec;
 	int ltrack;
 	int end;
-	int cyl;
-	int track;
 
 	lsec = off/dp->t->bytes;
 	ltrack = lsec/dp->t->sectors;
@@ -647,6 +645,7 @@ floppysense(void)
 static int
 cmddone(void *a)
 {
+	USED(a);
 	return fl.ncmd == 0;
 }
 
@@ -665,8 +664,6 @@ floppywait(void)
 static int
 floppyrecal(Drive *dp)
 {
-	int type;
-
 	dp->ccyl = -1;
 
 	fl.ncmd = 0;
@@ -784,7 +781,6 @@ static long
 floppyxfer(Drive *dp, int cmd, void *a, long off, long n)
 {
 	long offset;
-	ulong up;
 
 	if(off >= dp->t->cap)
 		return 0;
@@ -866,6 +862,7 @@ floppyxfer(Drive *dp, int cmd, void *a, long off, long n)
 static void
 floppyintr(Ureg *ur)
 {
+	USED(ur);
 	switch(fl.cmd[0]&~Fmulti){
 	case Fread:
 	case Fwrite:
diff --git a/pc/devhard.c b/pc/devhard.c
index bb2887934368685c2c3fb11db797a71a46bc1f02..6c3ca865ae77c4c441c41099d395ef8f17185275 100644
--- a/pc/devhard.c
+++ b/pc/devhard.c
@@ -157,7 +157,7 @@ Drive		*hard;
 
 static void	hardintr(Ureg*);
 static long	hardxfer(Drive*, Partition*, int, long, long);
-static long	hardident(Drive*);
+static void	hardident(Drive*);
 static void	hardsetbuf(Drive*, int);
 static void	hardpart(Drive*);
 
@@ -171,6 +171,7 @@ hardgen(Chan *c, Dirtab *tab, long ntab, long s, Dir *dirp)
 	Partition *pp;
 	ulong l;
 
+	USED(tab, ntab);
 	qid.vers = 0;
 	drive = s/Npart;
 	s = s % Npart;
@@ -304,23 +305,27 @@ hardopen(Chan *c, int omode)
 void
 hardcreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
 void
 hardclose(Chan *c)
 {
+	USED(c);
 }
 
 void
 hardremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void
 hardwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
@@ -481,7 +486,6 @@ static long
 hardxfer(Drive *dp, Partition *pp, int cmd, long start, long len)
 {
 	Controller *cp;
-	int err;
 	long lblk;
 	int cyl, sec, head;
 	int loop;
@@ -590,7 +594,7 @@ hardsetbuf(Drive *dp, int on)
 /*
  *  get parameters from the drive
  */
-static long
+static void
 hardident(Drive *dp)
 {
 	Controller *cp;
@@ -758,6 +762,7 @@ hardintr(Ureg *ur)
 	Drive *dp;
 	long loop;
 
+	USED(ur);
 	spllo();	/* let in other interrupts */
 
 	/*
diff --git a/pc/devincon.c b/pc/devincon.c
index 2024e26647a8667156baa1702c72692361c24997..ebf37801aaac7a1ee013e96af27b97fd088564f3 100644
--- a/pc/devincon.c
+++ b/pc/devincon.c
@@ -544,6 +544,7 @@ inconopen(Chan *c, int omode)
 void	 
 inconcreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -589,6 +590,7 @@ inconwrite(Chan *c, void *buf, long n, ulong offset)
 	Incon *ip;
 	int data;
 
+	USED(offset);
 	switch(c->qid.path){
 	default:
 		return streamwrite(c, buf, n, 0);
@@ -617,12 +619,14 @@ inconwrite(Chan *c, void *buf, long n, ulong offset)
 void	 
 inconremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void	 
 inconwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
@@ -872,7 +876,7 @@ static void
 inconkproc(void *arg)
 {
 	Incon *ip;
-	Block *bp, *nbp;
+	Block *bp;
 	int i;
 	int locked;
 
@@ -1072,6 +1076,7 @@ inconintr(Ureg *ur)
 	int pcr;
 	Incon *ip;
 
+	USED(ur);
 	ip = &incon[0];
 	pcr = inb(ip->dev+Qpcr);
 	status = irdstatus(ip);
diff --git a/pc/devlpt.c b/pc/devlpt.c
index 2760e66f8c753196f0a26300c38bdaaf8eda4088..8e152ac8faaf9bea5f108ef3b7e3e01f4f4ceb4d 100644
--- a/pc/devlpt.c
+++ b/pc/devlpt.c
@@ -121,22 +121,27 @@ lptopen(Chan *c, int omode)
 void
 lptcreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
 void
 lptclose(Chan *c)
-{}
+{
+	USED(c);
+}
 
 void
 lptremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void
 lptwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
@@ -210,5 +215,6 @@ lptready(void *base)
 static void
 lptintr(Ureg *ur)
 {
+	USED(ur);
 	wakeup(&lptrendez);
 }
diff --git a/pc/devrtc.c b/pc/devrtc.c
index f0fde64c8e21ddf84f2e851af03d9455135d6b83..662205be233cad1d66bf5325168ebadb97677a39 100644
--- a/pc/devrtc.c
+++ b/pc/devrtc.c
@@ -90,12 +90,14 @@ rtcopen(Chan *c, int omode)
 void	 
 rtccreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
 void	 
 rtcclose(Chan *c)
 {
+	USED(c);
 }
 
 #define GETBCD(o) ((bcdclock[o]&0xf) + 10*(bcdclock[o]>>4))
@@ -103,10 +105,7 @@ rtcclose(Chan *c)
 long	 
 rtctime(void)
 {
-	int i,j;
-	uchar ch;
 	uchar bcdclock[Nbcd];
-	char atime[64];
 	Rtc rtc;
 
 	outb(Paddr, Status);
@@ -166,12 +165,10 @@ rtcwrite(Chan *c, void *buf, long n, ulong offset)
 {
 	Rtc rtc;
 	ulong secs;
-	int i,j;
-	uchar ch;
 	uchar bcdclock[Nbcd];
-	uchar *nv;
 	char *cp, *ep;
 
+	USED(c);
 	if(offset!=0)
 		error(Ebadarg);
 
@@ -216,12 +213,14 @@ rtcwrite(Chan *c, void *buf, long n, ulong offset)
 void	 
 rtcremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void	 
 rtcwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
diff --git a/pc/devuart.c b/pc/devuart.c
index 0567254e16c25baa91c5d3f32e7cf5fd85cd7cac..6a6c0c581ec770e46ac145f68ef71f214adce4e6 100644
--- a/pc/devuart.c
+++ b/pc/devuart.c
@@ -193,7 +193,7 @@ void
 uartputs(IOQ *cq, char *s, int n)
 {
 	Uart *up = cq->ptr;
-	int st, ch, x;
+	int ch, x;
 	int tries;
 
 	x = splhi();
@@ -274,11 +274,13 @@ uartintr(Uart *up)
 void
 uartintr0(Ureg *ur)
 {
+	USED(ur);
 	uartintr(&uart[0]);
 }
 void
 uartintr1(Ureg *ur)
 {
+	USED(ur);
 	uartintr(&uart[1]);
 }
 
@@ -302,8 +304,6 @@ uartclock(void)
 void
 uartenable(Uart *up)
 {
-	int x;
-
 	/*
 	 *  turn on power to the port
 	 */
@@ -343,6 +343,7 @@ uartenable(Uart *up)
 /*
  *  turn off the uart
  */
+void
 uartdisable(Uart *up)
 {
 
@@ -654,6 +655,7 @@ uartopen(Chan *c, int omode)
 void
 uartcreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -667,6 +669,7 @@ uartclose(Chan *c)
 long
 uartread(Chan *c, void *buf, long n, ulong offset)
 {
+	USED(offset);
 	switch(c->qid.path&~CHDIR){
 	case Qdir:
 		return devdirread(c, buf, n, uartdir, NUart, devgen);
@@ -680,17 +683,20 @@ uartread(Chan *c, void *buf, long n, ulong offset)
 long
 uartwrite(Chan *c, void *va, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, va, n, 0);
 }
 
 void
 uartremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void
 uartwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
diff --git a/pc/devvga.c b/pc/devvga.c
index 907a128b64f336cf7d14a54b7ddb140dbc678cc9..60e41330aee2e2197db71248ef55d0219018fbdb 100644
--- a/pc/devvga.c
+++ b/pc/devvga.c
@@ -108,20 +108,21 @@ vgaopen(Chan *c, int omode)
 void
 vgacreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
 void
 vgaclose(Chan *c)
 {
+	USED(c);
 }
 
 long
 vgaread(Chan *c, void *buf, long n, ulong offset)
 {
 	char obuf[60];
-	int port, i;
-	uchar *mem;
+	int port;
 	uchar *cp = buf;
 	void *outfunc(int, int);
 
@@ -156,7 +157,7 @@ long
 vgawrite(Chan *c, void *buf, long n, ulong offset)
 {
 	char cbuf[20], *cp;
-	int port, i, maxx, maxy;
+	int port, maxx, maxy;
 
 	switch(c->qid.path&~CHDIR){
 	case Qdir:
@@ -203,11 +204,13 @@ vgawrite(Chan *c, void *buf, long n, ulong offset)
 void
 vgaremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void
 vgawstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
diff --git a/pc/dma.c b/pc/dma.c
index b63fb1de68b5fc0240152ecd805c5928004895fa..c58b07c8d31cea7f435b57b688e860ca6c1d540a 100644
--- a/pc/dma.c
+++ b/pc/dma.c
@@ -149,8 +149,6 @@ dmaend(int chan)
 {
 	DMA *dp;
 	DMAxfer *xp;
-	ulong addr;
-	uchar mode;
 
 	dp = &dma[(chan>>2)&1];
 	chan = chan & 3;
diff --git a/pc/kbd.c b/pc/kbd.c
index 607b9348809bcd9b444ee99a01c1d7364ad701bf..17b6c3109ecfcc0a33fdf87c5be9a5e4186958c4 100644
--- a/pc/kbd.c
+++ b/pc/kbd.c
@@ -185,8 +185,7 @@ i8042a20(void)
 void
 kbdinit(void)
 {
-	int c, s;
-	int tries;
+	int c;
 
 	setvec(Kbdvec, kbdintr);
 
@@ -241,7 +240,6 @@ mymouseputc(int c)
 	static int nb;
 	static uchar b[] = {0, 1, 4, 5, 2, 3, 6, 7};
 	static lastdx, lastdy;
-	int diff;
 	extern Mouseinfo mouse;
 
 	/* 
@@ -289,7 +287,7 @@ middle(int newval)
 int
 kbdintr0(void)
 {
-	int s, c, i, nk, nc;
+	int s, c, i, nk;
 	static int esc1, esc2;
 	static int shift;
 	static int caps;
@@ -442,5 +440,6 @@ dochar:
 void
 kbdintr(Ureg *ur)
 {
+	USED(ur);
 	kbdintr0();
 }
diff --git a/pc/main.c b/pc/main.c
index 7797e167dd6a3232d1efe7c31975c42fdff36d4a..fbd032ac83b42cdc08189bcc39d76e6346df860c 100644
--- a/pc/main.c
+++ b/pc/main.c
@@ -67,8 +67,6 @@ ulong garbage;
 void
 init0(void)
 {
-	Chan *c;
-
 	u->nerrlab = 0;
 	m->proc = u->p;
 	u->p->state = Running;
@@ -174,7 +172,6 @@ bootargs(ulong base)
 {
  	int i, ac;
 	uchar *av[32];
-	char *p, *pp;
 	uchar **lsp;
 
 	sp = (uchar*)base + BY2PG - MAXSYSARG*BY2WD;
@@ -306,6 +303,7 @@ matherror(Ureg *ur)
 void
 mathemu(Ureg *ur)
 {
+	USED(ur);
 	switch(u->p->fpstate){
 	case FPinit:
 		fpinit();
@@ -327,6 +325,7 @@ mathemu(Ureg *ur)
 void
 mathover(Ureg *ur)
 {
+	USED(ur);
 	pexit("Math overrun", 0);
 }
 
@@ -355,6 +354,7 @@ procsetup(Proc *p)
 void
 procsave(Proc *p)
 {
+	USED(p);
 	if(u->p->fpstate == FPactive){
 		fpsave(&u->fpsave);
 		u->p->fpstate = FPinactive;
@@ -367,6 +367,7 @@ procsave(Proc *p)
 void
 procrestore(Proc *p)
 {
+	USED(p);
 }
 
 
@@ -395,8 +396,6 @@ meminit(void)
 void
 exit(void)
 {
-	int i;
-
 	u = 0;
 	print("exiting\n");
 	switch(machtype){
diff --git a/pc/mmu.c b/pc/mmu.c
index f08638f743ee4760f82063460819915aa422942f..3634d7f4ccd908c9dde6653d37d7b9fae478fa7e 100644
--- a/pc/mmu.c
+++ b/pc/mmu.c
@@ -213,8 +213,6 @@ flushmmu(void)
 void
 mapstack(Proc *p)
 {
-	ulong tlbphys;
-	int i;
 	Page *pg;
 	ulong *top;
 
@@ -292,8 +290,6 @@ putmmu(ulong va, ulong pa, Page *pg)
 	ulong *top;
 	ulong *pt;
 	Proc *p;
-	char err[64];
-	int x;
 
 	if(u==0)
 		panic("putmmu");
diff --git a/pc/pmu.c b/pc/pmu.c
index e0a453fd5e7444a6f80b4b1d84375b129d178812..88fc8f5e40ba36fe7fdd285c7bfe0addf9f637dc 100644
--- a/pc/pmu.c
+++ b/pc/pmu.c
@@ -130,6 +130,7 @@ pmubuzz(int f, int d)
 	static QLock bl;
 	static Rendez br;
 
+	USED(f);
 	qlock(&bl);
 	pmuwrbit(0, 0, 6);
 	tsleep(&br, return0, 0, d);
diff --git a/pc/segment.h b/pc/segment.h
index 09583003a19e98469bbee8ab55e4700cb0d6cbe9..6ae272a2e96cd0dc4544f36ae5bb88861210bf3a 100644
--- a/pc/segment.h
+++ b/pc/segment.h
@@ -12,9 +12,9 @@ struct Physseg
 	Page	*(*pgalloc)(ulong);	/* Allocation if we need it */
 	void	(*pgfree)(Page*);
 }physseg[] = {
-	{ SG_SHARED,	"lock",		0,	SEGMAXSIZE,	&snewpage, 	&putpage },
-	{ SG_SHARED,	"shared",	0,	SEGMAXSIZE,	&snewpage, 	&putpage },
+	{ SG_SHARED,	"lock",		0,	SEGMAXSIZE,	snewpage, 	putpage },
+	{ SG_SHARED,	"shared",	0,	SEGMAXSIZE,	snewpage, 	putpage },
 	{ SG_PHYSICAL,	"kmem",		KZERO,	SEGMAXSIZE,	0,		0 	},
-	{ SG_BSS,	"memory",	0,	SEGMAXSIZE,	&snewpage,	&putpage },
+	{ SG_BSS,	"memory",	0,	SEGMAXSIZE,	snewpage,	putpage },
 	{ 0,		0,		0,	0,		0,		0 	},
 };
diff --git a/pc/vga.c b/pc/vga.c
index 4a88f8b88015823349e89bc9a3c130283a1f9223..38a73d5f177efba95aac69fa3a45585854ab88a1 100644
--- a/pc/vga.c
+++ b/pc/vga.c
@@ -224,7 +224,9 @@ dumpmodes(void) {
 #endif
 
 void
-setscreen(int maxx, int maxy, int bpp) {
+setscreen(int maxx, int maxy, int bpp)
+{
+	USED(bpp);
 	gbitblt(&gscreen, Pt(0, 0), &gscreen, gscreen.r, flipD[S]);
 	gscreen.width = maxx/32;
 	gscreen.r.max = Pt(maxx, maxy);
@@ -238,10 +240,8 @@ setscreen(int maxx, int maxy, int bpp) {
 void
 screeninit(void)
 {
-	int i, j, k;
-	int c;
+	int i;
 	ulong *l;
-	VGAmode testmode;
 
 	setmode(&mode12);
 
@@ -334,18 +334,21 @@ getcolor(ulong p, ulong *pr, ulong *pg, ulong *pb)
 int
 setcolor(ulong p, ulong r, ulong g, ulong b)
 {
+	USED(p, r, g, b);
 	return 0;	/* can't change mono screen colormap */
 }
 
 int
 hwcursset(uchar *s, uchar *c, int ox, int oy)
 {
+	USED(s, c, ox, oy);
 	return 0;
 }
 
 int
 hwcursmove(int x, int y)
 {
+	USED(x, y);
 	return 0;
 }
 
diff --git a/port/alarm.c b/port/alarm.c
index 557d54663a6a2d79cdf0db79b8bbf96f513d2be1..e2f9ec34ce40ba5bed7fc1e08d81a8a1482858b7 100644
--- a/port/alarm.c
+++ b/port/alarm.c
@@ -14,7 +14,6 @@ alarmkproc(void *arg)
 {
 	Proc *rp;
 	ulong now;
-	int i, n, s;
 
 	USED(arg);
 
diff --git a/port/chan.c b/port/chan.c
index 3476c16ccc870e9e97523254a2c4539ae7faca5f..3bc416daf0f4cb9b16f8d32ac10d52358c446745 100644
--- a/port/chan.c
+++ b/port/chan.c
@@ -27,8 +27,6 @@ int
 decref(Ref *r)
 {
 	int x;
-	int i;
-	Segment *s;
 
 	lock(r);
 	x = --r->ref;
@@ -432,7 +430,7 @@ namec(char *name, int amode, int omode, ulong perm)
 	int t;
 	int mntok, isdot;
 	char *p;
-	char *elem, *nn;
+	char *elem;
 	char createerr[ERRLEN];
 
 	if(name[0] == 0)
@@ -668,8 +666,8 @@ nameok(char *elem)
 char*
 nextelem(char *name, char *elem)
 {
-	int i, user, w;
-	char *end, *e;
+	int w;
+	char *end;
 	Rune r;
 
 	if(*name == '/')
diff --git a/port/dev.c b/port/dev.c
index fc55c6fd7ea1a0cb52d9033a6fa7b044f39fc664..3785a5612f2741ae876cd030e92d165e1966e553 100644
--- a/port/dev.c
+++ b/port/dev.c
@@ -57,6 +57,7 @@ devattach(int tc, char *spec)
 {
 	Chan *c;
 
+	USED(spec);
 	c = newchan();
 	c->qid = (Qid){CHDIR, 0};
 	c->type = devno(tc, 0);
diff --git a/port/devarp.c b/port/devarp.c
index aeb0c35fbc096b03382c4871c9898019d32038fc..d207dcd2cd1b8884ad7696995d2a68ef848965a9 100644
--- a/port/devarp.c
+++ b/port/devarp.c
@@ -74,6 +74,9 @@ arpgen(Chan *c, void *vp, int ntab, int i, Dir *dp)
 {
 	Qid q;
 
+	USED(vp);
+	USED(ntab);
+
 	q.vers = 0;
 
 	/* top level directory contains the directory arp */
@@ -200,9 +203,9 @@ long
 arpread(Chan *c, void *a, long n, ulong offset)
 {
 	char	 buf[100];
-	Arpcache *ap, *ep;
+	Arpcache *ap;
 	int	 part, bytes, size;
-	char	 *ptr, *ststr;
+	char	 *ststr;
 
 	switch((int)(c->qid.path&~CHDIR)){
 	case arpdirqid:
@@ -255,6 +258,8 @@ arpwrite(Chan *c, char *a, long n, ulong offset)
 	char	 buf[20], *field[5];
 	int 	 m;
 
+	USED(offset);
+
 	switch(STREAMTYPE(c->qid.path)) {
 	case arpctlqid:
 
diff --git a/port/devbit.c b/port/devbit.c
index 9fe0347078ade284d59e4fdcf15b5268058ea03b..cd95bd0ecda6dd0de1b5f9946d939426e1156ef1 100644
--- a/port/devbit.c
+++ b/port/devbit.c
@@ -242,8 +242,7 @@ bitdebug(void)
 void
 bitreset(void)
 {
-	int i, ws;
-	GBitmap *bp;
+	int ws;
 	ulong r;
 	Arena *a;
 
@@ -700,7 +699,7 @@ long
 bitwrite(Chan *c, void *va, long n, ulong offset)
 {
 	uchar *p, *q;
-	long m, v, miny, maxy, minx, maxx, t, x, y;
+	long m, v, miny, maxy, t, x, y;
 	ulong l, nw, ws, rv, q0, q1;
 	int off, isoff, i, j, ok;
 	Point pt, pt1, pt2;
@@ -708,11 +707,13 @@ bitwrite(Chan *c, void *va, long n, ulong offset)
 	Cursor curs;
 	Fcode fc;
 	Fontchar *fcp;
-	GBitmap *b, *src, *dst, *bp;
+	GBitmap *src, *dst;
 	BSubfont *f, *tf, **fp;
 	GFont *ff, **ffp;
 	GCacheinfo *gc;
 
+	USED(offset);
+
 	if(c->qid.path == CHDIR)
 		error(Eisdir);
 
@@ -1450,12 +1451,10 @@ bitwrite(Chan *c, void *va, long n, ulong offset)
 int
 bitalloc(Rectangle rect, int ld)
 {
-	Arena *a, *ea, *na, *aa;
+	Arena *a, *ea, *aa;
 	GBitmap *b, **bp, **ep;
-	BSubfont *s;
 	ulong l, ws, nw;
 	long t;
-	int i, try;
 
 	ws = BI2WD>>ld;	/* pixels per word */
 	if(rect.min.x >= 0){
@@ -1674,7 +1673,7 @@ bitloadchar(GFont *f, int ci, GSubfont *subf, int si)
 void
 bitcompact(void)
 {
-	Arena *a, *b, *ea, *na;
+	Arena *a, *ea, *na;
 	ulong *p1, *p2, n;
 
 	ea = &bit.arena[bit.narena];
diff --git a/port/devboot.c b/port/devboot.c
index f1b8fd02b255cc3c3655b3ad5685b666c6fbee1b..e13656e8c705bf1a4af8a3a043edf7fdfa03da7b 100644
--- a/port/devboot.c
+++ b/port/devboot.c
@@ -62,7 +62,7 @@ bootopen(Chan *c, int omode)
 void	 
 bootcreate(Chan *c, char *name, int omode, ulong perm)
 {
-	USED(c);
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -130,6 +130,6 @@ bootremove(Chan *c)
 void	 
 bootwstat(Chan *c, char *dp)
 {
-	USED(c);
+	USED(c, dp);
 	error(Eperm);
 }
diff --git a/port/devconc.c b/port/devconc.c
index 6b658f1342f1e085e75ec2c50ea843a409da1243..12e12b59ff138fc7ab9bbdd320262f7c1c5d9b9d 100644
--- a/port/devconc.c
+++ b/port/devconc.c
@@ -283,7 +283,7 @@ concdevstclose(Queue *q)
 	q->ptr = 0;
 	q->other->ptr = 0;
 	dp->rq = 0;
-	streamexit(cp->s, 1);
+	streamexit(cp->s);
 	qunlock(cp);
 }
 
@@ -376,6 +376,7 @@ concgen(Chan *c, Dirtab *tab, int ntab, int i, Dir *dp)
 	Conc *cp;
 	char buf[16];
 
+	USED(tab, ntab);
 	cp = &concs[c->dev];
 	switch(c->qid.path){
 	case CHDIR:
@@ -445,7 +446,7 @@ concopen(Chan *c, int omode)
 void	 
 conccreate(Chan *c, char *name, int omode, ulong perm)
 {
-	USED(c);
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -459,6 +460,7 @@ concclose(Chan *c)
 long	 
 concread(Chan *c, void *a, long n, ulong offset)
 {
+	USED(offset);
 	if(c->stream)
 		return streamread(c, a, n);
 	if(c->qid.path & CHDIR)
@@ -470,6 +472,7 @@ concread(Chan *c, void *a, long n, ulong offset)
 long	 
 concwrite(Chan *c, void *a, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, a, n, 0);
 }
 
@@ -483,6 +486,6 @@ concremove(Chan *c)
 void	 
 concwstat(Chan *c, char *dp)
 {
-	USED(c);
+	USED(c, dp);
 	error(Eperm);
 }
diff --git a/port/devcons.c b/port/devcons.c
index c60e34841ff490fedcf7277022efa73628e30359..a31ba8249f530f53b98442cf6981b7c4f543de68 100644
--- a/port/devcons.c
+++ b/port/devcons.c
@@ -489,10 +489,8 @@ consread(Chan *c, void *buf, long n, ulong offset)
 {
 	int ch, i, j, k, id;
 	ulong l;
-	uchar *out;
 	char *cbuf = buf;
-	char *user, *chal;
-	int userlen;
+	char *chal;
 	Block *cb;
 	char tmp[6*NUMSIZE], xbuf[512];
 	Mach *mp;
@@ -685,7 +683,6 @@ consread(Chan *c, void *buf, long n, ulong offset)
 void
 conslights(char *a, int n)
 {
-	int l;
 	char line[128];
 	char *lp;
 	int c;
diff --git a/port/devdk.c b/port/devdk.c
index 26deeb8b0226f892d7beda74e7ea3efae53ef106..8392530efb3cc55762fea41a6e11e57b5acac25f 100644
--- a/port/devdk.c
+++ b/port/devdk.c
@@ -696,6 +696,9 @@ void
 dkcreate(Chan *c, char *name, int omode, ulong perm)
 {
 	USED(c);
+	USED(name);
+	USED(omode);
+	USED(perm);
 	error(Eperm);
 }
 
@@ -720,6 +723,7 @@ dkwrite(Chan *c, void *a, long n, ulong offset)
 	char *field[5];
 	int m;
 
+	USED(offset);
 	t = STREAMTYPE(c->qid.path);
 
 	/*
@@ -840,8 +844,6 @@ dkopenline(Dk *dp, int line)
 static Chan*
 dkopencsc(Dk *dp)
 {
-	Line *lp;
-
 	qlock(&dp->csclock);
 	if(dp->csc == 0)
 		dp->csc = dkopenline(dp, dp->ncsc);
@@ -1321,7 +1323,6 @@ static void
 dkwindow(Chan *c)
 {
 	char buf[64];
-	long wins;
 	Line *lp;
 
 	lp = linealloc(dk[c->dev], STREAMID(c->qid.path), 1);
@@ -1517,7 +1518,6 @@ dkchgmesg(Chan *c, Dk *dp, Dkmsg *dialp, int line)
 static void
 dkreplymesg(Dk *dp, Dkmsg *dialp, int line)
 {
-	Proc *p;
 	Line *lp;
 
 	DPRINT("dkreplymesg(%d)\n", line);
@@ -1557,7 +1557,7 @@ dkreplymesg(Dk *dp, Dkmsg *dialp, int line)
 static void
 dktimer(void *a)
 {
-	int dki, i;
+	int i;
 	Dk *dp;
 	Line *lp;
 	Chan *c;
diff --git a/port/devdup.c b/port/devdup.c
index 277ad03500bd845bc61164e8302c9a1ec56436b6..ceea1efea96af3d5b64b6c2460e857060d3e3a4c 100644
--- a/port/devdup.c
+++ b/port/devdup.c
@@ -16,6 +16,8 @@ dupgen(Chan *c, Dirtab *tab, int ntab, int s, Dir *dp)
 	Chan *f;
 	static int perm[] = { 0400, 0200, 0600, 0 };
 
+	USED(tab);
+	USED(ntab);
 	if(s >= NFD)
 		return -1;
 	if((f=fgrp->fd[s]) == 0)
@@ -99,6 +101,7 @@ void
 dupwstat(Chan *c, char *dp)
 {
 	USED(c);
+	USED(dp);
 	error(Egreg);
 }
 
@@ -113,6 +116,7 @@ dupread(Chan *c, void *va, long n, ulong offset)
 {
 	char *a = va;
 
+	USED(offset);
 	if(c->qid.path != CHDIR)
 		panic("dupread");
 	return devdirread(c, a, n, (Dirtab *)0, 0L, dupgen);
diff --git a/port/devenv.c b/port/devenv.c
index 00de34b596c257754d63ac10c0e32333a7e82422..dffe3b039b052d0a9e2d66f29014e8ed18e3c9c6 100644
--- a/port/devenv.c
+++ b/port/devenv.c
@@ -28,6 +28,9 @@ envgen(Chan *c, Dirtab *tab, int ntab, int s, Dir *dp)
 	Egrp *eg;
 	Evalue *e;
 
+	USED(tab);
+	USED(ntab);
+
 	eg = u->p->egrp;
 	qlock(eg);
 
@@ -109,6 +112,7 @@ envcreate(Chan *c, char *name, int omode, ulong perm)
 	Egrp *eg;
 	Evalue *e;
 
+	USED(perm);
 	if(c->qid.path != CHDIR)
 		error(Eperm);
 
diff --git a/port/devip.c b/port/devip.c
index 95eec41e91bc7658ede7681853d82574512ddca6..7f216a2b4ddcbd22b6fac119ea782e2ebb3c3f14 100644
--- a/port/devip.c
+++ b/port/devip.c
@@ -37,8 +37,6 @@ Qinfo *protocols[] = { &tcpinfo, &udpinfo, &ilinfo, 0 };
 void
 ipinitifc(Ipifc *ifc, Qinfo *stproto)
 {
-	int j;
-
 	ifc->conv = xalloc(Nipconv * sizeof(Ipconv*));
 	ifc->protop = stproto;
 	ifc->nconv = Nipconv;
@@ -267,6 +265,7 @@ ipwrite(Chan *c, char *a, long n, ulong offset)
 	Port	port;
 	Ipconv  *cp;
 
+	USED(offset);
 	type = STREAMTYPE(c->qid.path);
 	if (type == Sdataqid)
 		return streamwrite(c, a, n, 0); 
@@ -588,7 +587,7 @@ udpstopen(Queue *q, Stream *s)
 	Ipconv *ipc;
 
 	ipc = ipcreateconv(ipifc[s->dev], s->id);
-	initipifc(ipifc[s->dev], IP_UDPPROTO, udprcvmsg, 1500, 512, ETHER_HDR, "UDP");
+	initipifc(ipifc[s->dev], IP_UDPPROTO, udprcvmsg, 1500, 512, ETHER_HDR);
 
 	ipc->readq = RD(q);	
 	RD(q)->ptr = (void *)ipc;
@@ -607,7 +606,6 @@ tcpstoput(Queue *q, Block *bp)
 {
 	Ipconv *s;
 	Tcpctl *tcb; 
-	int len, errnum;
 	Block *f;
 
 	s = (Ipconv *)(q->ptr);
@@ -687,7 +685,7 @@ tcpstopen(Queue *q, Stream *s)
 	if(tcpbase == 0)
 		tcpbase = ipifc[s->dev]->conv;
 	ifc = ipifc[s->dev];
-	initipifc(ifc, IP_TCPPROTO, tcp_input, 1500, 512, ETHER_HDR, "TCP");
+	initipifc(ifc, IP_TCPPROTO, tcp_input, 1500, 512, ETHER_HDR);
 	ipc = ipcreateconv(ifc, s->id);
 
 	ipc->readq = RD(q);
@@ -711,6 +709,8 @@ ipremotefill(Chan *c, char *buf, int len)
 {
 	Ipconv *cp;
 
+	if(len < 24)
+		error(Ebadarg);
 	cp = ipcreateconv(ipifc[c->dev], STREAMID(c->qid.path));
 	sprint(buf, "%d.%d.%d.%d %d\n", fmtaddr(cp->dst), cp->pdst);
 }
@@ -720,6 +720,8 @@ iplocalfill(Chan *c, char *buf, int len)
 {
 	Ipconv *cp;
 
+	if(len < 24)
+		error(Ebadarg);
 	cp = ipcreateconv(ipifc[c->dev], STREAMID(c->qid.path));
 	sprint(buf, "%d.%d.%d.%d %d\n", fmtaddr(Myip[Myself]), cp->psrc);
 }
@@ -730,6 +732,8 @@ ipstatusfill(Chan *c, char *buf, int len)
 	int connection;
 	Ipconv *cp;
 
+	if(len < 64)
+		error(Ebadarg);
 	connection = STREAMID(c->qid.path);
 	cp = ipcreateconv(ipifc[c->dev], connection);
 	if(cp->ifc->protop == &tcpinfo)
@@ -756,7 +760,6 @@ iplisten(Chan *c)
 	Ipconv **p, **etab, *new;
 	Ipconv *s;
 	int connection;
-	Ipconv *cp;
 
 	connection = STREAMID(c->qid.path);
 	s = ipcreateconv(ipifc[c->dev], connection);
@@ -1074,7 +1077,7 @@ nextport(Ipifc *ifc, int priv)
 /* NEEDS HASHING ! */
 
 Ipconv*
-ip_conn(Ipifc *ifc, Port dst, Port src, Ipaddr dest, char proto)
+ip_conn(Ipifc *ifc, Port dst, Port src, Ipaddr dest)
 {
 	Ipconv **p, *s, **etab;
 
@@ -1104,6 +1107,7 @@ ip_conn(Ipifc *ifc, Port dst, Port src, Ipaddr dest, char proto)
 void
 bsdopen(Queue *q, Stream *s)
 {
+	USED(s);
 	RD(q)->ptr = q;
 	WR(q)->ptr = q;
 }
@@ -1125,9 +1129,7 @@ void
 bsdoput(Queue *q, Block *bp)
 {
 	uchar *luser;
-	uchar *p;
 	Block *nbp;
-	int n;
 
 	/* just pass it on if we've done authentication */
 	if(q->ptr == 0 || bp->type != M_DATA){
diff --git a/port/deviproute.c b/port/deviproute.c
index ce2df89874984eac60e3e1adaee593fb94700935..806860a097fa06b3392d72e7ee44236cd1b7c8ab 100644
--- a/port/deviproute.c
+++ b/port/deviproute.c
@@ -91,7 +91,6 @@ void
 ipaddroute(ulong dst, ulong mask, ulong gate)
 {
 	Iproute *r, *e, *free;
-	int i;
 
 	/*
 	 *  filter out impossible requests
@@ -330,6 +329,8 @@ iproutewrite(Chan *c, char *a, long n, ulong offset)
 	Ipaddr mask, dst, gate;
 	int m;
 
+	USED(offset);
+
 	switch((int)(c->qid.path&~CHDIR)){
 	case Qdata:
 		strncpy(buf, a, sizeof buf);
diff --git a/port/devkprof.c b/port/devkprof.c
index 5f397b9b6993e6163126b0f4ec2b9e7919d9b733..584a7eb4578295709a5e32b946cd7374678da42d 100644
--- a/port/devkprof.c
+++ b/port/devkprof.c
@@ -160,6 +160,8 @@ kprofread(Chan *c, void *va, long n, ulong offset)
 long
 kprofwrite(Chan *c, char *a, long n, ulong offset)
 {
+	USED(offset);
+
 	switch((int)(c->qid.path&~CHDIR)){
 	case Kprofctlqid:
 		if(strncmp(a, "startclr", 8) == 0){
diff --git a/port/devlance.c b/port/devlance.c
index e37444e9b46488ca40a82e1a6df883256ee5d7a2..ffc4a0f2d14bade6139e6cf1cdebc25859f0ce3e 100644
--- a/port/devlance.c
+++ b/port/devlance.c
@@ -454,7 +454,6 @@ static void
 lancestart(int mode)
 {
 	int i;
-	Etherpkt *p;
 	Lancemem *lm = LANCEMEM;
 	Msg *m;
 
@@ -617,6 +616,7 @@ lanceread(Chan *c, void *a, long n, ulong offset)
 long	 
 lancewrite(Chan *c, void *a, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, a, n, 0);
 }
 
@@ -689,7 +689,6 @@ lanceclonecon(Chan *c)
 void
 lanceintr(void)
 {
-	int i;
 	ushort csr;
 
 	csr = *l.rdp;
diff --git a/port/devmux.c b/port/devmux.c
index 981bd6c117cabbb5a41cb9d1f459ffaa624e9837..5f56cc9f6f3c34ed4b4364e91c80c2b61ca552f1 100644
--- a/port/devmux.c
+++ b/port/devmux.c
@@ -77,6 +77,7 @@ muxgen(Chan *c, Dirtab *tab, int ntab, int s, Dir *dp)
 	char buf[10];
 	int nq;
 
+	USED(tab, ntab);
 	if(c->qid.path == CHDIR) {
 		if(s >= Nmuxchan)
 			return -1;
@@ -190,7 +191,7 @@ muxopen(Chan *c, int omode)
 {
 	Mux *m;
 	Con *cm, *e;
-	int mux, ok;
+	int mux;
 	Chan *new;
 
 	c = devopen(c, omode, 0, 0, muxgen);
@@ -406,6 +407,7 @@ muxread(Chan *c, void *va, long n, ulong offset)
 	Con *cm;
 	int bread;
 
+	USED(offset);
 	if(c->qid.path & CHDIR)
 		return devdirread(c, va, n, 0, 0, muxgen);
 
@@ -449,9 +451,9 @@ muxwrite(Chan *c, void *va, long n, ulong offset)
 	Mux *m;
 	Con *cm;
 	int muxid, fd;
-	Block *f, *bp;
 	char *a, hdr[3], buf[10];
 
+	USED(offset);
 	if(c->qid.path&CHDIR)
 		error(Eisdir);
 
@@ -589,7 +591,7 @@ havedata(Dtq *q)
 ulong
 muxreadq(Mux *m, Dtq *q, char *va, ulong n)
 {
-	int l, nread, gotdelim;
+	int l, nread;
 	Block *bp, *f1;
 
 	qlock(&q->rd);
diff --git a/port/devpipe.c b/port/devpipe.c
index f7e63bd4f6cc191ab324c40beda7fe08e9a16e26..36ae10521a4d000a05b6409dddcd622b29620ecf 100644
--- a/port/devpipe.c
+++ b/port/devpipe.c
@@ -213,7 +213,7 @@ pipeclose(Chan *c)
 		remote = c->stream->devq->ptr;
 		if(streamclose(c) == 0){
 			if(remote)
-				streamexit(remote, 0);
+				streamexit(remote);
 		}
 		qunlock(p);
 	}
@@ -239,6 +239,7 @@ pipeclose(Chan *c)
 long
 piperead(Chan *c, void *va, long n, ulong offset)
 {
+	USED(offset);
 	if(c->qid.path & CHDIR)
 		return devdirread(c, va, n, pipedir, NPIPEDIR, pipegen);
 
@@ -252,6 +253,7 @@ piperead(Chan *c, void *va, long n, ulong offset)
 long
 pipewrite(Chan *c, void *va, long n, ulong offset)
 {
+	USED(offset);
 	if(waserror()) {
 		postnote(u->p, 1, "sys: write on closed pipe", NExit);
 		error(Egreg);
diff --git a/port/devproc.c b/port/devproc.c
index 88006375654cd972c568a92fb0e574ccf301cd96..f57abff85a1a09910b1658a225b191b5276d2781 100644
--- a/port/devproc.c
+++ b/port/devproc.c
@@ -64,6 +64,7 @@ procgen(Chan *c, Dirtab *tab, int ntab, int s, Dir *dp)
 	char buf[NAMELEN];
 	ulong pid, path, perm;
 
+	USED(ntab);
 	if(c->qid.path == CHDIR){
 		if(s >= conf.nproc)
 			return -1;
@@ -137,7 +138,6 @@ procopen(Chan *c, int omode)
 {
 	Proc *p;
 	Pgrp *pg;
-	Segment *s;
 	Chan *tc;
 
 	if(c->qid.path & CHDIR)
@@ -235,7 +235,6 @@ procread(Chan *c, void *va, long n, ulong offset)
 	KMap *k;
 	int i, j;
 	long l;
-	long pid;
 	User *up;
 	Segment *sg;
 
diff --git a/port/devroot.c b/port/devroot.c
index 91c9814ecb2a253930cd1e5512d96397cbc405c6..2a4cba44fa4dd2592bb2d959ac7cccc69285f43f 100644
--- a/port/devroot.c
+++ b/port/devroot.c
@@ -45,6 +45,8 @@ int	nroot;
 int
 rootgen(Chan *c, Dirtab *tab, int ntab, int i, Dir *dp)
 {
+	USED(ntab);
+
 	if(i >= nroot)
 		return -1;
 
diff --git a/port/devscc.c b/port/devscc.c
index 31fca51bc1b877e8561a1f05a8152f38273928a0..d65dad92168bfe104041c1797a2bac23aec6369d 100644
--- a/port/devscc.c
+++ b/port/devscc.c
@@ -194,7 +194,6 @@ sccparity(SCC *sp, char type)
 void
 sccbits(SCC *sp, int n)
 {
-	int val;
 	int rbits, tbits;
 
 	switch(n){
@@ -743,7 +742,6 @@ sccclose(Chan *c)
 long
 sccread(Chan *c, void *buf, long n, ulong offset)
 {
-	SCC *sp;
 	char b[8];
 
 	if(c->qid.path == CHDIR)
@@ -763,6 +761,7 @@ sccread(Chan *c, void *buf, long n, ulong offset)
 long
 sccwrite(Chan *c, void *va, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, va, n, 0);
 }
 
diff --git a/port/devscsi.c b/port/devscsi.c
index bb9977aa1a26e1062e4ea5ff12ecd3d723f7fb24..e2ce5c5907b21633f8c822a7425fc4faff333496 100644
--- a/port/devscsi.c
+++ b/port/devscsi.c
@@ -96,12 +96,14 @@ scsigen1(Chan *c, long qid, Dir *dp)
 static int
 scsigeno(Chan *c, Dirtab *tab, long ntab, long s, Dir *dp)
 {
+	USED(tab, ntab, s);
 	return scsigen1(c, c->qid.path, dp);
 }
 
 static int
 scsigen(Chan *c, Dirtab *tab, long ntab, long s, Dir *dp)
 {
+	USED(tab, ntab);
 	if (c->qid.path == CHDIR) {
 		if (0<=s && s<=7)
 			return scsigen1(c, CHDIR|0x100|(s<<4), dp);
@@ -148,6 +150,7 @@ scsiopen(Chan *c, int omode)
 void
 scsicreate(Chan *c, char *name, int omode, ulong perm)
 {
+	USED(c, name, omode, perm);
 	error(Eperm);
 }
 
@@ -303,12 +306,14 @@ scsiwrite(Chan *c, char *a, long n, ulong offset)
 void
 scsiremove(Chan *c)
 {
+	USED(c);
 	error(Eperm);
 }
 
 void
 scsiwstat(Chan *c, char *dp)
 {
+	USED(c, dp);
 	error(Eperm);
 }
 
@@ -559,6 +564,7 @@ scsiinit(void)
 static int
 scsidone(void *arg)
 {
+	USED(arg);
 	return (scsibusy == 0);
 }
 
diff --git a/port/devsrv.c b/port/devsrv.c
index bbcc18eb0e138af77b7e40960c2d519e4400f11b..74cdb6e77a24f1f41f42d9144e1374d8c8111cf9 100644
--- a/port/devsrv.c
+++ b/port/devsrv.c
@@ -27,6 +27,8 @@ srvgen(Chan *c, Dirtab *tab, int ntab, int s, Dir *dp)
 {
 	Srv *sp;
 
+	USED(tab);
+	USED(ntab);
 	qlock(&srvlk);
 	for(sp = srv; sp && s; sp = sp->link)
 		s--;
@@ -148,7 +150,6 @@ srvcreate(Chan *c, char *name, int omode, ulong perm)
 void
 srvremove(Chan *c)
 {
-	Chan *f;
 	Srv *sp, **l;
 
 	if(c->qid.path == CHDIR)
@@ -197,6 +198,7 @@ srvclose(Chan *c)
 long
 srvread(Chan *c, void *va, long n, ulong offset)
 {
+	USED(offset);
 	isdir(c);
 	return devdirread(c, va, n, 0, 0, srvgen);
 }
@@ -207,9 +209,10 @@ srvwrite(Chan *c, void *va, long n, ulong offset)
 	Srv *sp;
 	Fgrp *f;
 	Chan *c1;
-	int i, fd;
+	int fd;
 	char buf[32];
 
+	USED(offset);
 	if(n >= sizeof buf)
 		error(Egreg);
 	memmove(buf, va, n);	/* so we can NUL-terminate */
diff --git a/port/devwren.c b/port/devwren.c
index e59a08c0acd2123dec23d9c886bbe5528e951577..f036e3b3cf7f7c145b9870cef4ac829bbb5a91c8 100644
--- a/port/devwren.c
+++ b/port/devwren.c
@@ -78,6 +78,7 @@ wrengen(Chan *c, Dirtab *tab, long ntab, long s, Dir *dirp)
 	Partition *pp;
 	ulong l;
 
+	USED(tab, ntab);
 	qid.vers = 0;
 	drive = c->dev;
 	if(drive >= Ndisk)
diff --git a/port/fault.c b/port/fault.c
index 403bf0d43627db4557e0bf70fe53c46d4632fad0..add79d030ce451be1a3ba9cabe56371c873b98bf 100644
--- a/port/fault.c
+++ b/port/fault.c
@@ -301,8 +301,6 @@ okaddr(ulong addr, ulong len, int write)
 void
 validaddr(ulong addr, ulong len, int write)
 {
-	Segment *s;
-
 	if(!okaddr(addr, len, write))
 		pexit("Suicide", 0);
 }
diff --git a/port/ipdat.h b/port/ipdat.h
index 16aba00b9cbd841b3a16d398803d4311007a2954..e3bcde57bdfd89558ea35e8eb0650ad0e930cb2c 100644
--- a/port/ipdat.h
+++ b/port/ipdat.h
@@ -442,8 +442,8 @@ void	ilstart(Ipconv *, int, int);
 int	inb_window(Tcpctl *, int);
 void	init_tcpctl(Ipconv *);
 void	initfrag(int);
-void	initipifc(Ipifc*, uchar, void (*)(Ipifc*, Block*), int, int, int, char*);
-Ipconv*	ip_conn(Ipifc*, Port, Port, Ipaddr dest, char proto);
+void	initipifc(Ipifc*, uchar, void (*)(Ipifc*, Block*), int, int, int);
+Ipconv*	ip_conn(Ipifc*, Port, Port, Ipaddr dest);
 ushort	ip_csum(uchar*);
 Block*	ip_reassemble(int, Block*, Etherhdr*);
 int	ipclonecon(Chan *);
diff --git a/port/net.c b/port/net.c
index 834eb7f0e697d9f039899d4fc20df427f1187a31..97ab15a87ca80d89ccdf3b431ae09c561a48441a 100644
--- a/port/net.c
+++ b/port/net.c
@@ -42,6 +42,7 @@ netgen(Chan *c, void *vp, int ntab, int i, Dir *dp)
 	int perm;
 	char *o;
 
+	USED(ntab);
 	q.vers = 0;
 
 	/* top level directory contains the name of the network */
diff --git a/port/page.c b/port/page.c
index fa290b5f1518e77dd7424a0171a4a39055c97ee2..18b837b3a087fcf05eea660b359f4aa5d20b04fb 100644
--- a/port/page.c
+++ b/port/page.c
@@ -350,7 +350,7 @@ Pte*
 ptecpy(Pte *old)
 {
 	Pte *new;
-	Page **src, **dst, **end;
+	Page **src, **dst;
 
 	new = ptealloc();
 	dst = &new->pages[old->first-old->pages];
diff --git a/port/pgrp.c b/port/pgrp.c
index 8c131b1c7e1d5a130aadabc74bb636e6399ca806..7927d3b0fcb685334a94c52721e5bc45e4265168 100644
--- a/port/pgrp.c
+++ b/port/pgrp.c
@@ -133,7 +133,7 @@ closefgrp(Fgrp *f)
 Mount*
 newmount(Mhead *mh, Chan *to)
 {
-	Mount *m, *f, *e;
+	Mount *m;
 
 	m = smalloc(sizeof(Mount));
 	m->to = to;
diff --git a/port/portfns.h b/port/portfns.h
index bc661b4714f0b00bdc0213bb434c73d713d6edea..975a2e9cf14e1962ebd860a70e296328c7da1b51 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -212,7 +212,7 @@ void		splx(int);
 int		streamclose(Chan*);
 int		streamclose1(Stream*);
 int		streamenter(Stream*);
-void		streamexit(Stream*, int);
+void		streamexit(Stream*);
 Devgen		streamgen;
 void		streaminit(void);
 void		streaminit0(void);
diff --git a/port/proc.c b/port/proc.c
index aa5742cab3fc249e17163f0d69180242fe916916..e590bf6c10ecad920910e8ea266b92b69603197d 100644
--- a/port/proc.c
+++ b/port/proc.c
@@ -52,7 +52,6 @@ void
 schedinit(void)		/* never returns */
 {
 	Proc *p;
-	Page *pg;
 
 	setlabel(&m->sched);
 	if(u){
@@ -152,7 +151,6 @@ runproc(void)
 {
 	Schedq *rq;
 	Proc *p;
-	int i;
 
 loop:
 	spllo();
@@ -731,8 +729,6 @@ kproc(char *name, void (*func)(void *), void *arg)
 	p->pgrp = kpgrp;
 	incref(kpgrp);
 
-	if(u->p->user[0] != '\0')
-		user = u->p->user;
 	strcpy(p->text, name);
 
 	p->nchild = 0;
diff --git a/port/segment.c b/port/segment.c
index 94515846c3921117036559e1c02eb43324ae0ab7..231135c710f4ef4155f7321b05ad293d544dcc14 100644
--- a/port/segment.c
+++ b/port/segment.c
@@ -396,7 +396,7 @@ done:
 ulong
 segattach(Proc *p, ulong attr, char *name, ulong va, ulong len)
 {
-	Segment *s, *ns, *new;
+	Segment *s, *ns;
 	Physseg *ps;
 	ulong newtop;
 	int i, sno;
diff --git a/port/stil.c b/port/stil.c
index b65a65b16277f6c0bd01380ca29827a84f794d1c..5227c18fb9e9d243f8f5007f395d0d2928777598 100644
--- a/port/stil.c
+++ b/port/stil.c
@@ -73,7 +73,7 @@ ilopen(Queue *q, Stream *s)
 	}
 
 	ipc = ipcreateconv(ipifc[s->dev], s->id);
-	initipifc(ipc->ifc, IP_ILPROTO, ilrcvmsg, 1500, 60, ETHER_HDR, "IL");
+	initipifc(ipc->ifc, IP_ILPROTO, ilrcvmsg, 1500, 60, ETHER_HDR);
 
 	ipc->readq = RD(q);	
 	RD(q)->ptr = (void *)ipc;
@@ -86,7 +86,6 @@ ilclose(Queue *q)
 {
 	Ipconv *s;
 	Ilcb *ic;
-	Block *bp, *next;
 
 	s = (Ipconv *)(q->ptr);
 	ic = &s->ilctl;
@@ -121,7 +120,7 @@ iloput(Queue *q, Block *bp)
 	Ilhdr *ih;
 	Ilcb *ic;
 	int dlen;
-	Block *np, *f;
+	Block *f;
 	ulong id;
 
 	ipc = (Ipconv *)(q->ptr);
@@ -266,7 +265,6 @@ ilrcvmsg(Ipifc *ifc, Block *bp)
 	Ipconv *s, **p, **etab, *new;
 	short sp, dp;
 	Ipaddr dst;
-	char *st;
 
 	ih = (Ilhdr *)bp->rptr;
 	plen = blen(bp);
@@ -499,7 +497,7 @@ _ilprocess(Ipconv *s, Ilhdr *h, Block *bp)
 void
 ilrexmit(Ilcb *ic)
 {
-	Block *nb, *bp;
+	Block *nb;
 	Ilhdr *h;
 
 	nb = 0;
@@ -713,7 +711,6 @@ ilackproc(void *a)
 	Ipifc *ifc;
 	Ipconv **base, **p, **end, *s;
 	Ilcb *ic;
-	Block *bp, *np;
 
 	ifc = (Ipifc*)a;
 	base = ifc->conv;
diff --git a/port/stip.c b/port/stip.c
index 8375df5209e2d9340dddeb4b9fd486a1478b62e1..4cdb786f5860d1898c0f8207d3236b2a8dcb4d47 100644
--- a/port/stip.c
+++ b/port/stip.c
@@ -95,7 +95,7 @@ ipetheropen(Queue *q, Stream *s)
  */
 void
 initipifc(Ipifc *ifc, uchar ptcl, void (*recvfun)(Ipifc*, Block *bp), int max,
-	int min, int hdrsize, char *name)
+	int min, int hdrsize)
 {
 	qlock(ifc);
 	ifc->iprcv = recvfun;
diff --git a/port/stlapd.c b/port/stlapd.c
index 2722591cf7a4bce8584116742914bafad8bd6ae4..4e7a8f82a1cfbb8e5468ee784c54bb8150d7e76b 100644
--- a/port/stlapd.c
+++ b/port/stlapd.c
@@ -171,6 +171,7 @@ lapdopen(Queue *q, Stream *s)
 	Lapd *lp;
 	char name[32];
 
+	USED(s);
 	for(lp=lapd; lp<&lapd[conf.nlapd]; lp++){
 		qlock(lp);
 		if(lp->state == 0)
@@ -201,8 +202,6 @@ lapdopen(Queue *q, Stream *s)
 static void
 mdl_assign(Lapd *lp)
 {
-	Block *b; uchar *p;
-
 	qlock(lp);
 	if (lp->state != NoTEI) {
 		qunlock(lp);
@@ -244,8 +243,6 @@ assigntei(Lapd *lp)
 static void
 dl_establish(Lapd *lp)
 {
-	Block *b; uchar *p;
-
 	qlock(lp);
 	if (lp->state != TEIassigned) {
 		qunlock(lp);
@@ -265,8 +262,6 @@ dl_establish(Lapd *lp)
 static void
 dl_release(Lapd *lp)
 {
-	Block *b; uchar *p;
-
 	qlock(lp);
 	if (lp->state != Multiframe) {
 		qunlock(lp);
@@ -613,6 +608,7 @@ lapdctloput(Lapd *lp, Queue *q, Block *bp)
 {
 	char *fields[2];
 
+	USED(lp);
 	switch(bp->type){
 	case M_CTL:
 		if(streamparse("debug", bp)){
diff --git a/port/stream.c b/port/stream.c
index 7bc46f843b8a6392e8b636c4ac1c34f0ef093f1e..b24d886d490b21149f4d9768800de4a8a7c93a11 100644
--- a/port/stream.c
+++ b/port/stream.c
@@ -637,9 +637,6 @@ static void	hangup(Stream*);
 int
 streamgen(Chan *c, Dirtab *tab, int ntab, int s, Dir *dp)
 {
-	Proc *p;
-	char buf[NAMELEN];
-
 	if(s < ntab)
 		tab = &tab[s];
 	else if(s < ntab + Shighqid - Slowqid + 1)
@@ -771,7 +768,7 @@ streamenter(Stream *s)
 			s->inuse++;
 			qunlock(hb);
 			if(s->opens == 0){
-				streamexit(s, 1);
+				streamexit(s);
 				return -1;
 			}
 			return 0;
@@ -785,11 +782,10 @@ streamenter(Stream *s)
  *  zero, free the stream.
  */
 void
-streamexit(Stream *s, int locked)
+streamexit(Stream *s)
 {
 	Queue *q;
 	Queue *nq;
-	char *name;
 	Sthash *hb;
 	Stream **l, *ns;
 
@@ -843,7 +839,6 @@ int
 streamclose1(Stream *s)
 {
 	Queue *q, *nq;
-	Block *bp;
 	int rv;
 
 	/*
@@ -883,7 +878,7 @@ streamclose1(Stream *s)
 	/*
 	 *  leave it and free it
 	 */
-	streamexit(s, 1);
+	streamexit(s);
 	return rv;
 }
 int
@@ -1181,6 +1176,12 @@ streamwrite(Chan *c, void *a, long n, int docopy)
 	Block *bp;
 	char *va;
 
+	/*
+	 *  docopy will get used if I ever figure out when to avoid copying
+	 *  data. -- presotto
+	 */
+	USED(docopy);
+
 	s = c->stream;
 
 	/*
diff --git a/port/streboot.c b/port/streboot.c
index 0d35815a1afc3a1e3c5d6e7048e6e1dcf543748e..9cdaba65b241d7bc86c40319708202023c7e3fd9 100644
--- a/port/streboot.c
+++ b/port/streboot.c
@@ -26,6 +26,7 @@ static void
 rebootopen(Queue *q, Stream *s)
 {
 	USED(q);
+	USED(s);
 	if(strcmp(u->p->user, eve) != 0)
 		error(Eperm);
 }
diff --git a/port/stsplice.c b/port/stsplice.c
index 100aea15e1a4986d1beefb02630dc5010670f8c2..a55dd90ccfbe093150abeb1ccd99a962c0eb3770 100644
--- a/port/stsplice.c
+++ b/port/stsplice.c
@@ -73,8 +73,6 @@ spliceoput(Queue *q, Block *bp)
 static void
 spliceiput(Queue *q, Block *bp)
 {
-	Stream *s;
-
 	if(bp->type == M_HANGUP)
 		PUTNEXT(q, bp);
 	else
diff --git a/port/sturp.c b/port/sturp.c
index c9b24d60dd59554d6479dafb155243eac1475a9f..e2e2f00a5d33ce24e1b3a9bfe445aef552e4d1ae 100644
--- a/port/sturp.c
+++ b/port/sturp.c
@@ -124,7 +124,7 @@ static void	sendctl(Urp*, int);
 static void	sendack(Urp*);
 static void	sendrej(Urp*);
 static void	initoutput(Urp*, int);
-static void	initinput(Urp*, int);
+static void	initinput(Urp*);
 static void	urpkproc(void *arg);
 static void	urpvomit(char*, Urp*);
 static void	tryoutput(Urp*);
@@ -148,9 +148,8 @@ static void
 urpopen(Queue *q, Stream *s)
 {
 	Urp *up;
-	int i;
-	char name[128];
 
+	USED(s);
 	if(!urpkstarted){
 		qlock(&urpkl);
 		if(!urpkstarted){
@@ -188,7 +187,7 @@ urpopen(Queue *q, Stream *s)
 	up->wq = q->other;
 	up->state = OPEN;
 	qunlock(up);
-	initinput(up, 0);
+	initinput(up);
 	initoutput(up, 0);
 }
 
@@ -206,7 +205,6 @@ isflushed(void *a)
 static void
 urpclose(Queue *q)
 {
-	Block *bp;
 	Urp *up;
 	int i;
 
@@ -334,7 +332,7 @@ urpciput(Queue *q, Block *bp)
 		sendctl(up, AINIT);
 		if(ctl == INIT1)
 			q->put = urpiput;
-		initinput(up, 0);
+		initinput(up);
 		break;
 
 	case INITREQ:
@@ -467,7 +465,7 @@ urpiput(Queue *q, Block *bp)
 		sendctl(up, AINIT);
 		if(ctl == INIT0)
 			q->put = urpciput;
-		initinput(up, 0);
+		initinput(up);
 		break;
 
 	case INITREQ:
@@ -569,20 +567,12 @@ static void
 urpctloput(Urp *up, Queue *q, Block *bp)
 {
 	char *fields[2];
-	int n;
-	int inwin=0, outwin=0;
+	int outwin;
 
 	switch(bp->type){
 	case M_CTL:
 		if(streamparse("init", bp)){
-			switch(getfields((char *)bp->rptr, fields, 2, ' ')){
-			case 2:
-				inwin = strtoul(fields[1], 0, 0);
-			case 1:
-				outwin = strtoul(fields[0], 0, 0);
-			}
-			USED(inwin);
-/*			initinput(up, inwin); */
+			outwin = strtoul((char*)bp->rptr, 0, 0);
 			initoutput(up, outwin);
 			freeb(bp);
 			return;
@@ -635,7 +625,6 @@ output(Urp *up)
 	Block *bp, *nbp;
 	ulong now;
 	Queue *q;
-	int n;
 	int i;
 
 	if(!canqlock(&up->xmit))
@@ -787,8 +776,6 @@ sendrej(Urp *up)
 static void
 sendack(Urp *up)
 {
-	Block *bp;
-
 	/*
 	 *  check the precondition for acking
 	 */
@@ -986,7 +973,7 @@ initoutput(Urp *up, int window)
  *  initialize input
  */
 static void
-initinput(Urp *up, int window)
+initinput(Urp *up)
 {
 	/*
 	 *  restart all sequence parameters
diff --git a/port/swap.c b/port/swap.c
index b2cafe2bbfc518b8c7596da521fa8613da2b0fd3..7b80afabeee9758e17796a3147d2801186d74381 100644
--- a/port/swap.c
+++ b/port/swap.c
@@ -7,7 +7,7 @@
 
 /* Predeclaration */
 void	pageout(Proc *p, Segment*);
-void	pagepte(int, Segment*, Page**);
+void	pagepte(int, Page**);
 int	needpages(void*);
 void	pager(void*);
 void	executeio(void);
@@ -188,7 +188,7 @@ pageout(Proc *p, Segment *s)
 			if(entry->modref & PG_REF)
 				entry->modref &= ~PG_REF;
 			else 
-				pagepte(type, s, pg);
+				pagepte(type, pg);
 
 			if(ioptr >= Maxpages)
 				goto out;
@@ -235,7 +235,7 @@ canflush(Proc *p, Segment *s)
 }
 
 void
-pagepte(int type, Segment *s, Page **pg)
+pagepte(int type, Page **pg)
 {
 	ulong daddr;
 	Page *outp;
diff --git a/port/sysfile.c b/port/sysfile.c
index d1585120dd0a53fb358bf061caf82ac70403dc6d..38c73c936baef8809b7435afe62629559e40925f 100644
--- a/port/sysfile.c
+++ b/port/sysfile.c
@@ -194,7 +194,7 @@ sysclose(ulong *arg)
 long
 unionread(Chan *c, void *va, long n)
 {
-	Chan *mc, *nc;
+	Chan *nc;
 	Pgrp *pg = u->p->pgrp;
 	long nr;
 
@@ -343,7 +343,6 @@ long
 sysfstat(ulong *arg)
 {
 	Chan *c;
-	long n;
 
 	validaddr(arg[1], DIRLEN, 1);
 	evenaddr(arg[1]);
@@ -356,7 +355,6 @@ long
 sysstat(ulong *arg)
 {
 	Chan *c;
-	long n;
 
 	validaddr(arg[1], DIRLEN, 1);
 	evenaddr(arg[1]);
@@ -390,8 +388,7 @@ bindmount(ulong *arg, int ismount)
 	Chan *c0, *c1;
 	ulong flag;
 	long ret;
-	char *p;
-	int t, fd;
+	int fd;
 	struct{
 		Chan	*chan;
 		char	*spec;
@@ -534,7 +531,6 @@ long
 syswstat(ulong *arg)
 {
 	Chan *c;
-	long n;
 
 	validaddr(arg[1], DIRLEN, 0);
 	nameok((char*)arg[1]);
@@ -554,7 +550,6 @@ long
 sysfwstat(ulong *arg)
 {
 	Chan *c;
-	long n;
 
 	validaddr(arg[1], DIRLEN, 0);
 	nameok((char*)arg[1]);
diff --git a/port/sysproc.c b/port/sysproc.c
index c99c0e17aa0105d5af34e45eadb0f43c53ba0150..988d352703bffb6f776d78b53ee3bb4a966e90b0 100644
--- a/port/sysproc.c
+++ b/port/sysproc.c
@@ -19,15 +19,13 @@ sysr1(ulong *arg)
 long
 sysrfork(ulong *arg)
 {
-	Chan *c;
 	KMap *k;
 	Pgrp *opg;
 	Egrp *oeg;
 	Fgrp *ofg;
-	Segment *s;
-	int n, on, i;
+	int n, i;
 	Proc *p, *parent;
-	ulong usp, upa, pid, flag;
+	ulong upa, pid, flag;
 	/*
 	 * used to compute last valid system stack address for copy
 	 */
@@ -206,14 +204,13 @@ sysexec(ulong *arg)
 {
 	Proc *p;
 	Segment *s, *ts;
-	ulong l, t, d, b, v;
+	ulong t, d, b;
 	int i;
-	Chan *tc, *c;
+	Chan *tc;
 	char **argv, **argp;
 	char *a, *charp, *file;
 	char *progarg[sizeof(Exec)/2+1], elem[NAMELEN];
 	ulong ssize, spage, nargs, nbytes, n, bssend;
-	ulong *sp;
 	int indir;
 	Exec exec;
 	char line[sizeof(Exec)];
@@ -506,8 +503,6 @@ sysdeath(ulong *arg)
 long
 syserrstr(ulong *arg)
 {
-	char buf[ERRLEN];
-
 	validaddr(arg[0], ERRLEN, 1);
 	memmove((char*)arg[0], u->error, ERRLEN);
 	strncpy(u->error, Enoerror, ERRLEN);
@@ -628,7 +623,7 @@ sysbrk_(ulong *arg)
 long
 sysrendezvous(ulong *arg)
 {
-	Proc *p, *d, **l;
+	Proc *p, **l;
 	int s, tag;
 	ulong val;
 
diff --git a/port/tcpif.c b/port/tcpif.c
index 6ced887ae15beb3be1e49fccaa56c3202c1fe08b..ca3856aee6d8b6ec6a5cc56f8e6d6fdd777e08b5 100644
--- a/port/tcpif.c
+++ b/port/tcpif.c
@@ -72,7 +72,6 @@ void
 tcpstart(Ipconv *s, int mode, ushort window, char tos)
 {
 	Tcpctl *tcb = &s->tcpctl;
-	char msg[NAMELEN+2];
 
 	if(tcb->state != Closed)
 		return;
diff --git a/port/tcpinput.c b/port/tcpinput.c
index 22158b528647f4875d5de591e2eb48084eebb859..ab9eacb3110aab93c0ce368e54e105ae3baf9605 100644
--- a/port/tcpinput.c
+++ b/port/tcpinput.c
@@ -24,6 +24,8 @@ reset(Ipaddr source, Ipaddr dest, char tos, ushort length, Tcp *seg)
 	char rflags;
 	Tcphdr ph;
 
+	USED(tos);		/* is this right??? */
+
 	if(seg->flags & RST)
 		return;
 
@@ -162,7 +164,7 @@ tcp_input(Ipifc *ifc, Block *bp)
 		return;
 	
 	/* Look for a connection, failing that attempt to establish a listen */
-	s = ip_conn(ifc, seg.dest, seg.source, source, IP_TCPPROTO);
+	s = ip_conn(ifc, seg.dest, seg.source, source);
 	if (s == 0) {
 		if(seg.flags & SYN){
 			/*
@@ -969,7 +971,6 @@ ntohtcp(Tcp *tcph, Block **bpp)
 {
 	ushort hdrlen;
 	ushort i, optlen;
-	Block *nbp;
 	Tcphdr *h;
 	uchar *optr;
 
diff --git a/power/clock.c b/power/clock.c
index 9b3b2983a3cb39ef7a7d317278217fac04316e91..a5b9fe13eeb5eecc0a78ecf115a347de2c4c09c9 100644
--- a/power/clock.c
+++ b/power/clock.c
@@ -10,7 +10,6 @@
 void
 delay(int ms)
 {
-	ulong t, *p;
 	int i;
 
 	ms *= 7000;	/* experimentally determined */
diff --git a/power/devcyc.c b/power/devcyc.c
index 628fa1968682e2bc6a76f7c0ea6f6570fd0f9790..8655e436d28ebdfb067addf44253cfe172690b47 100644
--- a/power/devcyc.c
+++ b/power/devcyc.c
@@ -221,8 +221,9 @@ cycread(Chan *c, void *buf, long n, ulong offset)
 	User *pu;
 	Commcyc *cp;
 	Cycmsg *mp, **cmp;
-	ulong l, m, isflush;
+	ulong l, m;
 
+	USED(offset);
 	cp = &cyclone[c->dev];
 	switch(c->qid.path & ~CHDIR){
 	case Qdir:
@@ -299,6 +300,7 @@ cycwrite(Chan *c, void *buf, long n, ulong offset)
 	Commcyc *cp;
 	Cycmsg *mp, **cmp;
 
+	USED(offset);
 	cp = &cyclone[c->dev];
 	switch(c->qid.path & ~CHDIR){
 	case Qdir:
diff --git a/power/devduart.c b/power/devduart.c
index 775fb67c489724e7f48c10b398a1d9ab26aa9cdc..d026c968ccb2e1c4cc181999bc5a3b4091f521cc 100644
--- a/power/devduart.c
+++ b/power/devduart.c
@@ -377,7 +377,7 @@ duartxintr(Port *p)
 void
 duartintr(void)
 {
-	int cause, status, c;
+	int cause;
 	Duartreg *reg;
 	Port *p;
 
@@ -467,7 +467,6 @@ duartputs(IOQ *cq, char *s, int n)
 {
 	int ch, x;
 	Port *p;
-	Duartreg *reg;
 
 	x = splhi();
 	lock(cq);
@@ -783,6 +782,9 @@ void
 duartcreate(Chan *c, char *name, int omode, ulong perm)
 {
 	USED(c);
+	USED(name);
+	USED(omode);
+	USED(perm);
 	error(Eperm);
 }
 
@@ -823,6 +825,7 @@ duartread(Chan *c, void *buf, long n, ulong offset)
 long
 duartwrite(Chan *c, void *va, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, va, n, 0);
 }
 
@@ -837,6 +840,7 @@ void
 duartwstat(Chan *c, char *p)
 {
 	USED(c);
+	USED(p);
 	error(Eperm);
 }
 
diff --git a/power/devhs.c b/power/devhs.c
index 40be8fe06ace3731f6edc76455e499db99b24be4..48354b91c362bede91390e15d08e0b96cc6936f0 100644
--- a/power/devhs.c
+++ b/power/devhs.c
@@ -206,6 +206,9 @@ void
 hscreate(Chan *c, char *name, int omode, ulong perm)
 {
 	USED(c);
+	USED(name);
+	USED(omode);
+	USED(perm);
 	error(Eperm);
 }
 
@@ -219,12 +222,14 @@ hsclose(Chan *c)
 long	 
 hsread(Chan *c, void *buf, long n, ulong offset)
 {
+	USED(offset);
 	return streamread(c, buf, n);
 }
 
 long	 
 hswrite(Chan *c, void *buf, long n, ulong offset)
 {
+	USED(offset);
 	return streamwrite(c, buf, n, 0);
 }
 
@@ -239,6 +244,7 @@ void
 hswstat(Chan *c, char *dp)
 {
 	USED(c);
+	USED(dp);
 	error(Eperm);
 }
 
@@ -563,7 +569,6 @@ static void
 hsintr(int vec)
 {
 	ushort csr;
-	HSdev *addr;
 	Hs *hp;
 
 	hp = &hs[vec - Intvec];
diff --git a/power/devrtc.c b/power/devrtc.c
index d95bbe2791012d9d32e3b5e887a98c14ed3bbc06..4a56273dc6a2b380b625dc7b3bb3098419dc89f2 100644
--- a/power/devrtc.c
+++ b/power/devrtc.c
@@ -104,6 +104,9 @@ void
 rtccreate(Chan *c, char *name, int omode, ulong perm)
 {
 	USED(c);
+	USED(name);
+	USED(omode);
+	USED(perm);
 	error(Eperm);
 }
 
@@ -215,6 +218,7 @@ void
 rtcwstat(Chan *c, char *dp)
 {
 	USED(c);
+	USED(dp);
 	error(Eperm);
 }
 
@@ -279,7 +283,6 @@ rtctime(void)
 	uchar ch;
 	uchar *nv;
 	uchar bcdclock[Nbcd];
-	char atime[64];
 	Rtc rtc;
 
 	nv = &((Nvram*)NVRAM)[NVRTC].val;
diff --git a/power/main.c b/power/main.c
index cb9c5b97b56855d35f0b78ce0e6ec17697e73cb7..31c537c94356f8a6ec2006cf214b82440f04dd95 100644
--- a/power/main.c
+++ b/power/main.c
@@ -90,7 +90,6 @@ vecinit(void)
 void
 vmereset(void)
 {
-	long i;
 	int noforce;
 
 	if(ioid >= IO3R1)
@@ -111,7 +110,6 @@ ioboardinit(void)
 {
 	long i;
 	int maxlevel;
-	ushort *sp;
 
 	ioid = *IOID;
 	if(ioid >= IO3R1)
@@ -180,9 +178,6 @@ launchinit(void)
 void
 init0(void)
 {
-	int i;
-	Chan *c;
-
 	m->proc = u->p;
 	u->p->state = Running;
 	u->p->mach = m;
@@ -216,7 +211,6 @@ userinit(void)
 	Segment *s;
 	User *up;
 	KMap *k;
-	int i;
 	char **av;
 	Page *pg;
 
@@ -413,7 +407,6 @@ confset(char *sym)
 {
 	char *val, *p;
 	Conftab *ct;
-	ulong x;
 
 	/*
  	 *  parse line
@@ -496,7 +489,7 @@ confprint(void)
 void
 confinit(void)
 {
-	long x, i, j, *l;
+	long x, i, *l;
 
 	/*
 	 *  copy configuration down from high memory
@@ -734,12 +727,14 @@ void
 buzz(int f, int d)
 {
 	USED(f);
+	USED(d);
 }
 
 int
 mouseputc(IOQ *q, int c)
 {
 	USED(q);
+	USED(c);
 	return 0;
 }
 
diff --git a/power/trap.c b/power/trap.c
index deaa8cda83cff2b22feaa2b1c5c7c42a32245949..6c6841334cacedaabd3d0b34ae60012da52c80c6 100644
--- a/power/trap.c
+++ b/power/trap.c
@@ -358,7 +358,6 @@ dumpregs(Ureg *ur)
 {
 	int i;
 	ulong *l;
-	int (*pr)(char*, ...);
 
 	if(u)
 		print("registers for %s %d\n", u->p->text, u->p->pid);
diff --git a/ss/bbmalloc.c b/ss/bbmalloc.c
index 4115cab7b76061232b0fec8fb182be6511778859..9e9025c4a505ae8f9989ab78b802ee33d39559f6 100644
--- a/ss/bbmalloc.c
+++ b/ss/bbmalloc.c
@@ -41,8 +41,6 @@ bbmalloc(int nbytes)
 void
 bbfree(void *p, int n)
 {
-	ulong *up;
-
 	if(p == bblast)
 		bbcur = (ulong *)(((char *)bblast) + n);
 }
diff --git a/ss/clock.c b/ss/clock.c
index 3fac265a8f0b3b3d5dd25d7dbdbcd4e7c03c5484..ebd65caa20fd1fd328392006e0857ce4f0116b86 100644
--- a/ss/clock.c
+++ b/ss/clock.c
@@ -10,7 +10,6 @@
 void
 delay(int ms)
 {
-	ulong t, *p;
 	int i;
 
 	ms *= 3000;	/* experimentally determined */
@@ -43,7 +42,6 @@ clock(Ureg *ur)
 {
 	Proc *p;
 	ulong i, nrun = 0;
-	Segment *s;
 
 	i = ctr->lim1;	/* clear interrupt */
 	USED(i);
diff --git a/ss/main.c b/ss/main.c
index aaf9e3f4c613ce41b8791144f4b466feb11b0e46..7426a74a4cd7171b515d3a712a8cba6ac9420ec5 100644
--- a/ss/main.c
+++ b/ss/main.c
@@ -14,8 +14,6 @@ uchar *intrreg;
 void
 main(void)
 {
-	int a;
-
 	u = 0;
 	memset(edata, 0, (char*)end-(char*)edata);
 
@@ -93,8 +91,6 @@ ioinit(void)
 void
 init0(void)
 {
-	Chan *c;
-
 	u->nerrlab = 0;
 	m->proc = u->p;
 	u->p->state = Running;
@@ -227,9 +223,8 @@ void
 lancesetup(Lance *lp)
 {
 	KMap *k;
-	ushort *sp;
 	uchar *cp;
-	ulong pa, pte, va;
+	ulong pa, va;
 	int i, j;
 
 	k = kmappa(ETHER, PTEIO|PTENOCACHE);
diff --git a/ss/mmu.c b/ss/mmu.c
index 2dfc29f236bfd637446f52f97270bd7f61b16840..8ad3491fde26af9b5a6ca73586d6448be38f85bf 100644
--- a/ss/mmu.c
+++ b/ss/mmu.c
@@ -76,7 +76,7 @@ mmurelease(Proc *p)
 int
 newpid(Proc *p)
 {
-	int i, j, k;
+	int i, j;
 	ulong t;
 	Proc *sp;
 
@@ -222,6 +222,7 @@ putmmu(ulong tlbvirt, ulong tlbphys, Page *pg)
 	ulong seg, l;
 	int j, k;
 
+	USED(pg);
 	splhi();
 	p = u->p;
 	tp = p->pidonmach[m->machno];
@@ -263,7 +264,6 @@ void
 putpmeg(ulong virt, ulong phys)
 {
 	int i;
-	int tp;
 
 	virt &= VAMASK;
 	virt &= ~(BY2PG-1);
@@ -287,8 +287,6 @@ int nflushmmu;
 void
 flushmmu(void)
 {
-	int tp;
-
 nflushmmu++;
 	splhi();
 	u->p->newtlb = 1;
@@ -378,9 +376,6 @@ kmapperm(Page *pg)
 void
 kunmap(KMap *k)
 {
-	ulong pte;
-	int i;
-
 	k->pa = 0;
 	lock(&kmapalloc);
 	k->next = kmapalloc.free;
diff --git a/ss/screen.c b/ss/screen.c
index 7cf8b37d49b90c9ad9fa82c55e0786090a46354d..0101c6cfce02850949187f4c2adc4d6c86f7ce64 100644
--- a/ss/screen.c
+++ b/ss/screen.c
@@ -259,17 +259,18 @@ kbdstate(IOQ *q, int c)
 	static int repeatc;
 	static int lstate;
 	static uchar kc[4];
-	uchar ch, code;
+	uchar ch;
 	int i, nk;
 
+	USED(q);
 	ch = kbdmap[shift][c&0x7F];
 	if(c==0x7F){	/* all keys up */
     norepeat:
 		kbdrepeat(0);
-		return;
+		return 0;
 	}
 	if(ch == 0xFF)	/* shouldn't happen; ignore */
-		return;
+		return 0;
 	if(c & 0x80){	/* key went up */
 		if(ch == 0xF0){		/* control */
 			shift &= ~2;
@@ -337,6 +338,7 @@ kbdstate(IOQ *q, int c)
 			break;
 		}
 	}
+	return 0;
 }
 
 void
@@ -376,18 +378,21 @@ getcolor(ulong p, ulong *pr, ulong *pg, ulong *pb)
 int
 setcolor(ulong p, ulong r, ulong g, ulong b)
 {
+	USED(p, r, g, b);
 	return 0;	/* can't change mono screen colormap */
 }
 
 int
 hwcursset(uchar *s, uchar *c, int ox, int oy)
 {
+	USED(s, c, ox, oy);
 	return 0;
 }
 
 int
 hwcursmove(int x, int y)
 {
+	USED(x, y);
 	return 0;
 }