Don't attempt to disable curses or print a summary during an app restart to prevent deadlocks.

cgminer.c

@@ -3264,14 +3264,14 @@ const
 #endif
 char **initial_args;
 
-static void clean_up(void);
+static void clean_up(bool restarting);
 
 void app_restart(void)
 {
 	applog(LOG_WARNING, "Attempting to restart %s", packagename);
 
 	__kill_work();
-	clean_up();
+	clean_up(true);
 
 #if defined(unix) || defined(__APPLE__)
 	if (forkpid > 0) {
@@ -7219,7 +7219,7 @@ void print_summary(void)
 	fflush(stdout);
 }
 
-static void clean_up(void)
+static void clean_up(bool restarting)
 {
 #ifdef HAVE_OPENCL
 	clear_adl(nDevs);
@@ -7234,18 +7234,22 @@ static void clean_up(void)
 #ifdef WIN32
 	timeEndPeriod(1);
 #endif
+	if (!restarting) {
+		/* Attempting to disable curses or print a summary during a
+		 * restart can lead to a deadlock. */
 #ifdef HAVE_CURSES
 		disable_curses();
 #endif
 		if (!opt_realquiet && successful_connect)
 			print_summary();
+	}
 
 	curl_global_cleanup();
 }
 
 void _quit(int status)
 {
-	clean_up();
+	clean_up(false);
 
 #if defined(unix) || defined(__APPLE__)
 	if (forkpid > 0) {