From: Antonio Radici <antonio@debian.org>
Date: Thu, 27 Feb 2014 16:38:41 +0100
Subject: 543467-thread-segfault

Added a patch to prevent segfault when Ctrl+R is hit
on a malformed group of messages.
(see upstream bug http://bugs.mutt.org/3335)

Gbp-Pq: Topic upstream
---
 flags.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/flags.c b/flags.c
index 5309bb7..133fa35 100644
--- a/flags.c
+++ b/flags.c
@@ -303,7 +303,10 @@ void mutt_tag_set_flag (int flag, int bf)
 int mutt_thread_set_flag (HEADER *hdr, int flag, int bf, int subthread)
 {
   THREAD *start, *cur = hdr->thread;
-  
+
+  if ( !hdr->thread )
+    return (-1);
+
   if ((Sort & SORT_MASK) != SORT_THREADS)
   {
     mutt_error _("Threading is not enabled.");