regex(3): Resolve issues with higher WARNS levels

libc is set for WARNS=2, but the incoming libregex will use WARNS=6.
Sprinkle some casts and (void)bc's to alleviate the warnings that come along
with the higher WARNS level.

These 'bc' parameters could be outright removed, but as of right now they
will be used in some parts of libregex land. Silence the warnings instead
rather than flip-flopping.

2 files changed, 28 insertions, 25 deletions

diff --git a/lib/libc/regex/engine.c b/lib/libc/regex/engine.c
index d31ccaf74d2f..dc7f2a6761d9 100644
--- a/lib/libc/regex/engine.c
+++ b/lib/libc/regex/engine.c
@@ -398,7 +398,7 @@ dissect(struct match *m,
 			es += OPND(m->g->strip[es]);
 			break;
 		case OCH_:
-			while (OP(m->g->strip[es]) != O_CH)
+			while (OP(m->g->strip[es]) != (sop)O_CH)
 				es += OPND(m->g->strip[es]);
 			break;
 		}
@@ -512,7 +512,7 @@ dissect(struct match *m,
 				assert(OP(m->g->strip[esub]) == OOR2);
 				ssub = esub + 1;
 				esub += OPND(m->g->strip[esub]);
-				if (OP(m->g->strip[esub]) == OOR2)
+				if (OP(m->g->strip[esub]) == (sop)OOR2)
 					esub--;
 				else
 					assert(OP(m->g->strip[esub]) == O_CH);
@@ -647,7 +647,7 @@ backref(struct match *m,
 			do {
 				assert(OP(s) == OOR2);
 				ss += OPND(s);
-			} while (OP(s = m->g->strip[ss]) != O_CH);
+			} while (OP(s = m->g->strip[ss]) != (sop)O_CH);
 			/* note that the ss++ gets us past the O_CH */
 			break;
 		default:	/* have to make a choice */
@@ -680,7 +680,7 @@ backref(struct match *m,
 		ssp = m->offp + m->pmatch[i].rm_so;
 		if (memcmp(sp, ssp, len) != 0)
 			return(NULL);
-		while (m->g->strip[ss] != SOP(O_BACK, i))
+		while (m->g->strip[ss] != (sop)SOP(O_BACK, i))
 			ss++;
 		return(backref(m, sp+len, stop, ss+1, stopst, lev, rec));
 	case OQUEST_:		/* to null or not */
@@ -712,13 +712,13 @@ backref(struct match *m,
 			if (dp != NULL)
 				return(dp);
 			/* that one missed, try next one */
-			if (OP(m->g->strip[esub]) == O_CH)
+			if (OP(m->g->strip[esub]) == (sop)O_CH)
 				return(NULL);	/* there is none */
 			esub++;
-			assert(OP(m->g->strip[esub]) == OOR2);
+			assert(OP(m->g->strip[esub]) == (sop)OOR2);
 			ssub = esub + 1;
 			esub += OPND(m->g->strip[esub]);
-			if (OP(m->g->strip[esub]) == OOR2)
+			if (OP(m->g->strip[esub]) == (sop)OOR2)
 				esub--;
 			else
 				assert(OP(m->g->strip[esub]) == O_CH);
@@ -847,7 +847,7 @@ walk(struct match *m, const char *start, const char *stop, sopno startst,
 			else
 				matchp = p;
 		}
-		if (EQ(st, empty) || p == stop || clen > stop - p)
+		if (EQ(st, empty) || p == stop || clen > (size_t)(stop - p))
 			break;		/* NOTE BREAK OUT */
 
 		/* no, we must deal with this character */
@@ -969,22 +969,22 @@ step(struct re_guts *g,
 			break;
 		case OCH_:		/* mark the first two branches */
 			FWD(aft, aft, 1);
-			assert(OP(g->strip[pc+OPND(s)]) == OOR2);
+			assert(OP(g->strip[pc+OPND(s)]) == (sop)OOR2);
 			FWD(aft, aft, OPND(s));
 			break;
 		case OOR1:		/* done a branch, find the O_CH */
 			if (ISSTATEIN(aft, here)) {
 				for (look = 1;
-						OP(s = g->strip[pc+look]) != O_CH;
-						look += OPND(s))
-					assert(OP(s) == OOR2);
+				    OP(s = g->strip[pc+look]) != (sop)O_CH;
+				    look += OPND(s))
+					assert(OP(s) == (sop)OOR2);
 				FWD(aft, aft, look + 1);
 			}
 			break;
 		case OOR2:		/* propagate OCH_'s marking */
 			FWD(aft, aft, 1);
-			if (OP(g->strip[pc+OPND(s)]) != O_CH) {
-				assert(OP(g->strip[pc+OPND(s)]) == OOR2);
+			if (OP(g->strip[pc+OPND(s)]) != (sop)O_CH) {
+				assert(OP(g->strip[pc+OPND(s)]) == (sop)OOR2);
 				FWD(aft, aft, OPND(s));
 			}
 			break;
diff --git a/lib/libc/regex/regcomp.c b/lib/libc/regex/regcomp.c
index e460e1456364..37d37a9bc52e 100644
--- a/lib/libc/regex/regcomp.c
+++ b/lib/libc/regex/regcomp.c
@@ -364,6 +364,7 @@ p_ere_exp(struct parse *p, struct branchc *bc)
 	sopno subno;
 	int wascaret = 0;
 
+	(void)bc;
 	assert(MORE());		/* caller should have ensured this */
 	c = GETNEXT();
 
@@ -534,6 +535,7 @@ p_branch_eat_delim(struct parse *p, struct branchc *bc)
 {
 	int nskip;
 
+	(void)bc;
 	nskip = 0;
 	while (EAT('|'))
 		++nskip;
@@ -587,6 +589,7 @@ static bool
 p_branch_empty(struct parse *p, struct branchc *bc)
 {
 
+	(void)bc;
 	SETERROR(REG_EMPTY);
 	return (false);
 }
@@ -1617,12 +1620,12 @@ findmust(struct parse *p, struct re_guts *g)
 				scan += OPND(s);
 				s = *scan;
 				/* assert() interferes w debug printouts */
-				if (OP(s) != O_QUEST && OP(s) != O_CH &&
-							OP(s) != OOR2) {
+				if (OP(s) != (sop)O_QUEST &&
+				    OP(s) != (sop)O_CH && OP(s) != (sop)OOR2) {
 					g->iflags |= BAD;
 					return;
 				}
-			} while (OP(s) != O_QUEST && OP(s) != O_CH);
+			} while (OP(s) != (sop)O_QUEST && OP(s) != (sop)O_CH);
 			/* FALLTHROUGH */
 		case OBOW:		/* things that break a sequence */
 		case OEOW:
@@ -1631,7 +1634,7 @@ findmust(struct parse *p, struct re_guts *g)
 		case O_QUEST:
 		case O_CH:
 		case OEND:
-			if (newlen > g->mlen) {		/* ends one */
+			if (newlen > (sopno)g->mlen) {		/* ends one */
 				start = newstart;
 				g->mlen = newlen;
 				if (offset > -1) {
@@ -1646,7 +1649,7 @@ findmust(struct parse *p, struct re_guts *g)
 			newlen = 0;
 			break;
 		case OANY:
-			if (newlen > g->mlen) {		/* ends one */
+			if (newlen > (sopno)g->mlen) {		/* ends one */
 				start = newstart;
 				g->mlen = newlen;
 				if (offset > -1) {
@@ -1664,7 +1667,7 @@ findmust(struct parse *p, struct re_guts *g)
 			break;
 		case OANYOF:		/* may or may not invalidate offset */
 			/* First, everything as OANY */
-			if (newlen > g->mlen) {		/* ends one */
+			if (newlen > (sopno)g->mlen) {		/* ends one */
 				start = newstart;
 				g->mlen = newlen;
 				if (offset > -1) {
@@ -1687,7 +1690,7 @@ findmust(struct parse *p, struct re_guts *g)
 			 * save the last known good offset, in case the
 			 * must sequence doesn't occur later.
 			 */
-			if (newlen > g->mlen) {		/* ends one */
+			if (newlen > (sopno)g->mlen) {		/* ends one */
 				start = newstart;
 				g->mlen = newlen;
 				if (offset > -1)
@@ -1748,7 +1751,7 @@ altoffset(sop *scan, int offset)
 	largest = 0;
 	try = 0;
 	s = *scan++;
-	while (OP(s) != O_QUEST && OP(s) != O_CH) {
+	while (OP(s) != (sop)O_QUEST && OP(s) != (sop)O_CH) {
 		switch (OP(s)) {
 		case OOR1:
 			if (try > largest)
@@ -1764,10 +1767,10 @@ altoffset(sop *scan, int offset)
 			do {
 				scan += OPND(s);
 				s = *scan;
-				if (OP(s) != O_QUEST && OP(s) != O_CH &&
-							OP(s) != OOR2)
+				if (OP(s) != (sop)O_QUEST &&
+				    OP(s) != (sop)O_CH && OP(s) != (sop)OOR2)
 					return -1;
-			} while (OP(s) != O_QUEST && OP(s) != O_CH);
+			} while (OP(s) != (sop)O_QUEST && OP(s) != (sop)O_CH);
 			/* We must skip to the next position, or we'll
 			 * leave altoffset() too early.
 			 */