build: fix unused parameters

Found with gcc 4.6 -Wunused -Wextra
but should be applicable to Plan 9 too.

R=ken2
CC=golang-dev
https://golang.org/cl/4958044

src/cmd/6g/gobj.c

@@ -537,6 +537,8 @@ genembedtramp(Type *rcvr, Type *method, Sym *newnam, int iface)
 	int c, d, o, mov, add, loaded;
 	Prog *p;
 	Type *f;
+	
+	USED(iface);
 
 	if(debug['r'])
 		print("genembedtramp %T %T %S\n", rcvr, method, newnam);

src/cmd/6g/gsubr.c

@@ -79,6 +79,8 @@ Prog*
 gbranch(int as, Type *t)
 {
 	Prog *p;
+	
+	USED(t);
 
 	p = prog(as);
 	p->to.type = D_BRANCH;

src/cmd/cov/main.c

@@ -337,6 +337,9 @@ cover(void)
 uvlong
 rgetzero(Map *map, char *reg)
 {
+	USED(map);
+	USED(reg);
+
 	return 0;
 }
 

src/cmd/gc/closure.c

@@ -129,6 +129,8 @@ makeclosure(Node *func, NodeList **init, int nowrap)
 	static int closgen;
 	char *p;
 
+	USED(init);
+
 	/*
 	 * wrap body in external function
 	 * with extra closure parameters.

src/cmd/gc/dcl.c

@@ -115,6 +115,8 @@ dumpdcl(char *st)
 	Sym *s, *d;
 	int i;
 
+	USED(st);
+
 	i = 0;
 	for(d=dclstack; d!=S; d=d->link) {
 		i++;

src/cmd/gc/lex.c

@@ -92,6 +92,8 @@ usage(void)
 void
 fault(int s)
 {
+	USED(s);
+
 	// If we've already complained about things
 	// in the program, don't bother complaining
 	// about the seg fault too; let the user clean up
@@ -446,6 +448,8 @@ importfile(Val *f, int line)
 	Strlit *path;
 	char *cleanbuf;
 
+	USED(line);
+
 	// TODO(rsc): don't bother reloading imports more than once?
 
 	if(f->ctype != CTSTR) {

src/cmd/gc/walk.c

@@ -1201,6 +1201,8 @@ makenewvar(Type *t, NodeList **init, Node **nstar)
 static Node*
 ascompatee1(int op, Node *l, Node *r, NodeList **init)
 {
+	USED(op);
+
 	return convas(nod(OAS, l, r), init);
 }
 
@@ -1257,6 +1259,8 @@ ascompatet(int op, NodeList *nl, Type **nr, int fp, NodeList **init)
 	int ucount;
 	NodeList *nn, *mm;
 
+	USED(op);
+
 	/*
 	 * check assign type list to
 	 * a expression list. called in

src/cmd/godefs/main.c

@@ -98,7 +98,10 @@ waitfor(int pid)
 int
 spawn(char *prog, char **argv)
 {
-	int pid = fork();
+	int pid;
+	
+	USED(prog);
+	pid = fork();
 	if(pid < 0)
 		sysfatal("fork: %r");
 	if(pid == 0) {

src/cmd/gopack/ar.c

@@ -1532,6 +1532,8 @@ arwrite(int fd, Armember *bp)
 int
 page(Arfile *ap)
 {
+	USED(ap);
+
 	sysfatal("page");
 	return 1;
 }

src/cmd/prof/main.c

@@ -386,6 +386,8 @@ addtohistogram(uvlong pc, uvlong callerpc, uvlong sp)
 {
 	int h;
 	PC *x;
+	
+	USED(sp);
 
 	h = (pc + callerpc*101) % Ncounters;
 	for(x = counters[h]; x != NULL; x = x->next) {
@@ -437,6 +439,8 @@ uvlong nextpc;
 void
 xptrace(Map *map, uvlong pc, uvlong sp, Symbol *sym)
 {
+	USED(map);
+
 	char buf[1024];
 	if(sym == nil){
 		fprint(2, "syms\n");

src/lib9/exitcode.c

@@ -29,6 +29,7 @@ THE SOFTWARE.
 int
 exitcode(char *s)
 {
+	USED(s);
 	return 1;
 }
 

src/libmach/executable.c

@@ -502,6 +502,8 @@ commonllp64(int unused, Fhdr *fp, ExecHdr *hp)
 	int32 pgsize;
 	uvlong entry;
 
+	USED(unused);
+
 	hswal(&hp->e, sizeof(Exec)/sizeof(int32), beswal);
 	if(!(hp->e.exechdr.magic & HDR_MAGIC))
 		return 0;
@@ -542,6 +544,10 @@ commonllp64(int unused, Fhdr *fp, ExecHdr *hp)
 static int
 mipsboot(int fd, Fhdr *fp, ExecHdr *hp)
 {
+	USED(fd);
+	USED(fp);
+	USED(hp);
+
 abort();
 #ifdef unused
 	USED(fd);
@@ -573,6 +579,10 @@ abort();
 static int
 mips4kboot(int fd, Fhdr *fp, ExecHdr *hp)
 {
+	USED(fd);
+	USED(fp);
+	USED(hp);
+
 abort();
 #ifdef unused
 	USED(fd);
@@ -604,6 +614,10 @@ abort();
 static int
 sparcboot(int fd, Fhdr *fp, ExecHdr *hp)
 {
+	USED(fd);
+	USED(fp);
+	USED(hp);
+
 abort();
 #ifdef unused
 	USED(fd);
@@ -624,6 +638,10 @@ abort();
 static int
 nextboot(int fd, Fhdr *fp, ExecHdr *hp)
 {
+	USED(fd);
+	USED(fp);
+	USED(hp);
+
 abort();
 #ifdef unused
 	USED(fd);
@@ -645,7 +663,6 @@ abort();
 static int
 elf64dotout(int fd, Fhdr *fp, ExecHdr *hp)
 {
-
 	uvlong (*swav)(uvlong);
 	uint32 (*swal)(uint32);
 	ushort (*swab)(ushort);

src/libmach/fakeobj.c

@@ -13,17 +13,17 @@
 #include <mach.h>
 #include "obj.h"
 
-int _is2(char* x) { return 0; }
-int _is7(char* x) { return 0; }
-int _is9(char* x) { return 0; }
-int _isk(char* x) { return 0; }
-int _isq(char* x) { return 0; }
-int _isv(char* x) { return 0; }
-int _isu(char* x) { return 0; }
-int _read2(Biobuf* b, Prog* p) { return 0; }
-int _read7(Biobuf* b, Prog* p) { return 0; }
-int _read9(Biobuf* b, Prog* p) { return 0; }
-int _readk(Biobuf* b, Prog* p) { return 0; }
-int _readq(Biobuf* b, Prog* p) { return 0; }
-int _readv(Biobuf* b, Prog* p) { return 0; }
-int _readu(Biobuf* b, Prog* p) { return 0; }
+int _is2(char* x) { USED(x); return 0; }
+int _is7(char* x) { USED(x); return 0; }
+int _is9(char* x) { USED(x); return 0; }
+int _isk(char* x) { USED(x); return 0; }
+int _isq(char* x) { USED(x); return 0; }
+int _isv(char* x) { USED(x); return 0; }
+int _isu(char* x) { USED(x); return 0; }
+int _read2(Biobuf* b, Prog* p) { USED(b); USED(p); return 0; }
+int _read7(Biobuf* b, Prog* p) { USED(b); USED(p); return 0; }
+int _read9(Biobuf* b, Prog* p) { USED(b); USED(p); return 0; }
+int _readk(Biobuf* b, Prog* p) { USED(b); USED(p); return 0; }
+int _readq(Biobuf* b, Prog* p) { USED(b); USED(p); return 0; }
+int _readv(Biobuf* b, Prog* p) { USED(b); USED(p); return 0; }
+int _readu(Biobuf* b, Prog* p) { USED(b); USED(p); return 0; }

src/libmach/linux.c

@@ -807,6 +807,8 @@ ptraceerr:
 static int
 ptracesegrw(Map *map, Seg *seg, uvlong addr, void *v, uint n, int isr)
 {
+	USED(seg);
+
 	return ptracerw(isr ? PTRACE_PEEKDATA : PTRACE_POKEDATA, PTRACE_PEEKDATA,
 		isr, map->pid, addr, v, n);
 }
@@ -937,6 +939,8 @@ ptraceregrw(Map *map, Seg *seg, uvlong addr, void *v, uint n, int isr)
 {
 	int laddr;
 	uvlong u;
+	
+	USED(seg);
 
 	if((laddr = go2linux(addr)) < 0){
 		if(isr){

src/libmach/map.c

@@ -137,6 +137,8 @@ int
 fdrw(Map *map, Seg *s, uvlong addr, void *v, uint n, int isread)
 {
 	int tot, m;
+	
+	USED(map);
 
 	for(tot=0; tot<n; tot+=m){
 		if(isread)