Fix various dead stores found by the clang static analyzer

http-push.c::finish_request():
  request is initialized by the for loop

index-pack.c::free_base_data():
  b is initialized by the for loop

merge-recursive.c::process_renames():
  move compare to narrower scope, and remove unused assignments to it
  remove unused variable renames2

xdiff/xdiffi.c::xdl_recs_cmp():
  remove unused variable ec

xdiff/xemit.c::xdl_emit_diff():
  xche is always overwritten

Signed-off-by: Benjamin Kramer <benny.kra@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

http-push.c

@@ -816,7 +816,7 @@ static void finish_request(struct transfer_request *request)
 #ifdef USE_CURL_MULTI
 static int fill_active_slot(void *unused)
 {
-	struct transfer_request *request = request_queue_head;
+	struct transfer_request *request;
 
 	if (aborted)
 		return 0;

index-pack.c

@@ -232,7 +232,7 @@ static void free_base_data(struct base_data *c)
 
 static void prune_base_data(struct base_data *retain)
 {
-	struct base_data *b = base_cache;
+	struct base_data *b;
 	for (b = base_cache;
 	     base_cache_used > delta_base_cache_limit && b;
 	     b = b->child) {

merge-recursive.c

@@ -801,22 +801,19 @@ static int process_renames(struct merge_options *o,
 	}
 
 	for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
-		int compare;
 		char *src;
-		struct string_list *renames1, *renames2, *renames2Dst;
+		struct string_list *renames1, *renames2Dst;
 		struct rename *ren1 = NULL, *ren2 = NULL;
 		const char *branch1, *branch2;
 		const char *ren1_src, *ren1_dst;
 
 		if (i >= a_renames->nr) {
-			compare = 1;
 			ren2 = b_renames->items[j++].util;
 		} else if (j >= b_renames->nr) {
-			compare = -1;
 			ren1 = a_renames->items[i++].util;
 		} else {
-			compare = strcmp(a_renames->items[i].string,
-					b_renames->items[j].string);
+			int compare = strcmp(a_renames->items[i].string,
+					     b_renames->items[j].string);
 			if (compare <= 0)
 				ren1 = a_renames->items[i++].util;
 			if (compare >= 0)
@@ -826,14 +823,12 @@ static int process_renames(struct merge_options *o,
 		/* TODO: refactor, so that 1/2 are not needed */
 		if (ren1) {
 			renames1 = a_renames;
-			renames2 = b_renames;
 			renames2Dst = &b_by_dst;
 			branch1 = o->branch1;
 			branch2 = o->branch2;
 		} else {
 			struct rename *tmp;
 			renames1 = b_renames;
-			renames2 = a_renames;
 			renames2Dst = &a_by_dst;
 			branch1 = o->branch2;
 			branch2 = o->branch1;

xdiff/xdiffi.c

@@ -293,15 +293,14 @@ int xdl_recs_cmp(diffdata_t *dd1, long off1, long lim1,
 		for (; off1 < lim1; off1++)
 			rchg1[rindex1[off1]] = 1;
 	} else {
-		long ec;
 		xdpsplit_t spl;
 		spl.i1 = spl.i2 = 0;
 
 		/*
 		 * Divide ...
 		 */
-		if ((ec = xdl_split(ha1, off1, lim1, ha2, off2, lim2, kvdf, kvdb,
-				    need_min, &spl, xenv)) < 0) {
+		if (xdl_split(ha1, off1, lim1, ha2, off2, lim2, kvdf, kvdb,
+			      need_min, &spl, xenv) < 0) {
 
 			return -1;
 		}

xdiff/xemit.c

@@ -132,7 +132,7 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
 	if (xecfg->flags & XDL_EMIT_COMMON)
 		return xdl_emit_common(xe, xscr, ecb, xecfg);
 
-	for (xch = xche = xscr; xch; xch = xche->next) {
+	for (xch = xscr; xch; xch = xche->next) {
 		xche = xdl_get_hunk(xch, xecfg);
 
 		s1 = XDL_MAX(xch->i1 - xecfg->ctxlen, 0);