Exit cleanly if we abort before various threads are set up or if they no longer exist.

main.c

@@ -2255,14 +2255,17 @@ void kill_work(void)
 
 	/* Kill the watchdog thread */
 	thr = &thr_info[watchdog_thr_id];
-	if (thr->pth)
+	if (thr && thr->pth)
 		pthread_cancel(*thr->pth);
 
 	/* Stop the mining threads*/
 	for (i = 0; i < mining_threads; i++) {
 		thr = &thr_info[i];
+		if (!thr)
+			continue;
 		if (!thr->pth)
 			continue;
+		if (thr->q)
 			tq_freeze(thr->q);
 		/* No need to check if this succeeds or not */
 		pthread_cancel(*thr->pth);
@@ -2270,10 +2273,10 @@ void kill_work(void)
 
 	/* Stop the others */
 	thr = &thr_info[stage_thr_id];
-	if (thr->pth)
+	if (thr && thr->pth)
 		pthread_cancel(*thr->pth);
 	thr = &thr_info[longpoll_thr_id];
-	if (thr->pth)
+	if (thr && thr->pth)
 		pthread_cancel(*thr->pth);
 
 	wc = calloc(1, sizeof(*wc));
@@ -2289,15 +2292,17 @@ void kill_work(void)
 	if (opt_debug)
 		applog(LOG_DEBUG, "Pushing die request to work thread");
 
-	if (unlikely(!tq_push(thr_info[work_thr_id].q, wc))) {
+	thr = &thr_info[work_thr_id];
+	if (thr) {
+		if (unlikely(!tq_push(thr->q, wc))) {
 			applog(LOG_ERR, "Failed to tq_push work in kill_work");
 			exit (1);
 		}
 
-	thr = &thr_info[work_thr_id];
 		if (thr->pth)
 			pthread_cancel(*thr->pth);
 	}
+}
 
 void quit(int status, const char *format, ...);