From 57c93d7e20cebf9f9cf0855cb4bac8217715e28a Mon Sep 17 00:00:00 2001
From: Con Kolivas <kernel@kolivas.org>
Date: Fri, 26 Aug 2011 13:02:15 +1000
Subject: [PATCH] Prevent segfault on exit for when accessory threads don't
 exist.

---
 main.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/main.c b/main.c
index 9daf28ce..f369be4e 100644
--- a/main.c
+++ b/main.c
@@ -1753,7 +1753,8 @@ void kill_work(void)
 
 	/* Kill the watchdog thread */
 	thr = &thr_info[watchdog_thr_id];
-	pthread_cancel(*thr->pth);
+	if (thr->pth)
+		pthread_cancel(*thr->pth);
 
 	/* Stop the mining threads*/
 	for (i = 0; i < mining_threads; i++) {
@@ -1767,9 +1768,11 @@ void kill_work(void)
 
 	/* Stop the others */
 	thr = &thr_info[stage_thr_id];
-	pthread_cancel(*thr->pth);
+	if (thr->pth)
+		pthread_cancel(*thr->pth);
 	thr = &thr_info[longpoll_thr_id];
-	pthread_cancel(*thr->pth);
+	if (thr->pth)
+		pthread_cancel(*thr->pth);
 
 	wc = calloc(1, sizeof(*wc));
 	if (unlikely(!wc)) {