From ba56640c30656757c57e9015890c2521d658ea79 Mon Sep 17 00:00:00 2001
From: Vitor Sessak <vitor1001@gmail.com>
Date: Fri, 4 Apr 2008 20:04:58 +0000
Subject: [PATCH] Fix possible segfault

Commited in SoC by Bobby Bingham on 2007-07-14 23:16:15

Originally committed as revision 12689 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavfilter/avfiltergraph.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libavfilter/avfiltergraph.c b/libavfilter/avfiltergraph.c
index 5211c762e1..d4b6bf1b87 100644
--- a/libavfilter/avfiltergraph.c
+++ b/libavfilter/avfiltergraph.c
@@ -112,7 +112,8 @@ int avfilter_graph_load_chain(AVFilterGraph *graph,
 
 fail:
     destroy_graph_filters(graph);
-    *first = *last = NULL;
+    if(first) *first = NULL;
+    if(last)  *last  = NULL;
     return -1;
 }