Clean up dead stores

Does not change optimized code (gcc -O).

Spotted by the Clang Static Analyzer.

src/lib/subs/aircombat.c

@@ -420,7 +420,6 @@ ac_airtoair(struct emp_qelem *att_list, struct emp_qelem *int_list)
     struct plist *interceptor;
     struct emp_qelem *att;
     struct emp_qelem *in;
-    int nplanes;
     int more_att;
     int more_int;
     struct emp_qelem *att_next;
@@ -439,9 +438,6 @@ ac_airtoair(struct emp_qelem *att_list, struct emp_qelem *int_list)
 	att_next = att->q_forw;
 	attacker = (struct plist *)att;
 	interceptor = (struct plist *)in;
-	nplanes = attacker->plane.pln_effic;
-	if (nplanes > interceptor->plane.pln_effic)
-	    nplanes = interceptor->plane.pln_effic;
 	ac_dog(attacker, interceptor);
 	in = in_next;
 	att = att_next;
@@ -751,8 +747,6 @@ ac_fireflak(struct emp_qelem *list, natid from, int guns)
     struct emp_qelem *next;
     char msg[255];
 
-    plp = (struct plist *)list->q_forw;
-
     for (qp = list->q_forw; qp != list; qp = next) {
 	next = qp->q_forw;
 	plp = (struct plist *)qp;

src/lib/subs/aswplnsubs.c

@@ -99,7 +99,6 @@ print_shiplist(struct shiplist *head)
 {
     struct shiplist *s;
     int first;
-    struct mchrstr *mp;
     struct shpstr ship;
 
     s = head;
@@ -107,7 +106,6 @@ print_shiplist(struct shiplist *head)
 
     while (s != NULL) {
 	getship(s->uid, &ship);
-	mp = &mchr[(int)ship.shp_type];
 	if (first) {
 	    pr(" #          player->owner           eff        type\n");
 	    first = 0;

src/lib/subs/border.c

@@ -54,7 +54,7 @@ blankfill(char *ptr, struct range *range, int size)
 	p = ptr;
 	while (--col >= 0)
 	    *p++ = ' ';
-	*p++ = 0;
+	*p = 0;
 	ptr += MAPWIDTH(size);
     }
 }

src/lib/subs/lndsub.c

@@ -178,10 +178,9 @@ lnd_take_casualty(int combat_mode, struct ulist *llp, int cas)
 
     taken = llp->unit.land.lnd_item[I_MILIT];
     /* Spies always die */
-    if (((struct lchrstr *)llp->chrp)->l_flags & L_SPY) {
-	eff_eq = 100;
+    if (((struct lchrstr *)llp->chrp)->l_flags & L_SPY)
 	llp->unit.land.lnd_effic = 0;
-    } else {
+    else {
 	eff_eq = ldround(cas * 100.0 /
 	    ((struct lchrstr *)llp->chrp)->l_item[I_MILIT], 1);
 	llp->unit.land.lnd_effic -= eff_eq;
@@ -1054,7 +1053,6 @@ lnd_mar_one_sector(struct emp_qelem *list, int dir, natid actor,
 	/* move survivors to done */
 	for (qp = cur.q_back; qp != &cur; qp = next) {
 	    next = qp->q_back;
-	    llp = (struct ulist *)qp;
 	    emp_remque(qp);
 	    emp_insque(qp, &done);
 	}

src/lib/subs/maps.c

@@ -175,7 +175,6 @@ draw_map(int bmap, char origin, int map_flags, struct nstr_sect *nsp)
 	switch (bmap) {
 	default:
 	    CANT_REACH();
-	    bmap = 'b';
 	    /* fall through */
 	case 'b':
 	    while (bmnxtsct(nsp) && !player->aborted) {

src/lib/subs/mission.c

@@ -1075,7 +1075,6 @@ air_damage(struct emp_qelem *bombers, coord x, coord y, int mission,
 	if (!plp->load)
 	    continue;
 
-	newdam = 0;
 	if (plp->pcp->pl_flags & P_A) {
 	    if (roll(100) > pln_identchance(pp, hardtarget, EF_SHIP)) {
 		wu(0, pp->pln_own,

src/lib/subs/mslsub.c

@@ -216,7 +216,6 @@ msl_intercept(struct plnstr *msl, struct sctstr *sp, int sublaunch,
 	      int news_item)
 {
     struct plnstr *pp;
-    struct plchrstr *pcp;
     struct emp_qelem *intlist;
     struct emp_qelem intfoo;
     struct emp_qelem *qp;
@@ -236,7 +235,6 @@ msl_intercept(struct plnstr *msl, struct sctstr *sp, int sublaunch,
 	pp = &ip->plane;
 	if (pp->pln_own != sp->sct_own)
 	    continue;
-	pcp = ip->pcp;
 	if (mission_pln_equip(ip, NULL, 'i') < 0) {
 	    emp_remque(qp);
 	    free(qp);
@@ -255,7 +253,6 @@ msl_intercept(struct plnstr *msl, struct sctstr *sp, int sublaunch,
 	next = qp->q_forw;
 	ip = (struct plist *)qp;
 	pp = &ip->plane;
-	pcp = ip->pcp;
 	if (mission_pln_equip(ip, NULL, 'i') < 0) {
 	    emp_remque(qp);
 	    free(qp);
@@ -287,7 +284,6 @@ msl_intercept(struct plnstr *msl, struct sctstr *sp, int sublaunch,
 	qp = intlist->q_forw;
 	ip = (struct plist *)qp;
 	pp = &ip->plane;
-	pcp = ip->pcp;
 
 	mpr(msl->pln_own, "%s %s launched in defense!\n",
 	    cname(pp->pln_own), def_name);

src/lib/subs/retreat.c

@@ -145,7 +145,6 @@ retreat_ship1(struct shpstr *sp, char code, int orig)
     if (sp->shp_own == 0)
 	return 0;
 
-    n = 0;
     if (sp->shp_effic < SHIP_MINEFF) {
 	wu(0, sp->shp_own,
 	   "%s %s,\nbut it died in the attack, and so couldn't retreat!\n",
@@ -405,7 +404,6 @@ retreat_land1(struct lndstr *lp, char code, int orig)
     if (lp->lnd_own == 0)
 	return 0;
 
-    n = 0;
     if (lp->lnd_effic < LAND_MINEFF) {
 	wu(0, lp->lnd_own,
 	   "%s %s,\nbut it died in the attack, and so couldn't retreat!\n",

src/lib/subs/takeover.c

@@ -130,7 +130,6 @@ takeover(struct sctstr *sp, natid newown)
      * n: random number from -25:75 + (50 - loyalty)
      */
     n = (50 - sp->sct_loyal) + ((random() % 100) - 25);
-    che_count = 0;
     if (n > 0 && sp->sct_own == sp->sct_oldown) {
 	che_count = (civ * n / 3000) + 5;
 	if (che_count * 2 > civ)