avconv.c:172: error: Integer Overflow L1
  ([-oo, 0] - 1):unsigned32 by call to `avformat_free_context`.

avconv.c:162:9: Call
160.         }
161.         av_freep(&filtergraphs[i]->outputs);
162.         av_freep(&filtergraphs[i]->graph_desc);
             ^
163.         av_freep(&filtergraphs[i]);
164.     }

libavutil/mem.c:181:5: Assignment
  179.     void **ptr = (void **)arg;
  180.     av_free(*ptr);
  181.     *ptr = NULL;
           ^
  182. }
  183. 

avconv.c:172:9: Call
170.         if (s && s->oformat && !(s->oformat->flags & AVFMT_NOFILE) && s->pb)
171.             avio_close(s->pb);
172.         avformat_free_context(s);
             ^
173.         av_dict_free(&output_files[i]->opts);
174.         av_freep(&output_files[i]);

libavformat/utils.c:2640:1: <LHS trace>
2638. }
2639. 
2640. void avformat_free_context(AVFormatContext *s)
      ^
2641. {
2642.     int i;

libavformat/utils.c:2640:1: Parameter `s->nb_chapters`
  2638. }
  2639. 
  2640. void avformat_free_context(AVFormatContext *s)
        ^
  2641. {
  2642.     int i;

libavformat/utils.c:2674:11: Binary operation: ([-oo, 0] - 1):unsigned32 by call to `avformat_free_context` 
  2672.     av_freep(&s->programs);
  2673.     av_freep(&s->priv_data);
  2674.     while(s->nb_chapters--) {
                  ^
  2675.         av_dict_free(&s->chapters[s->nb_chapters]->metadata);
  2676.         av_free(s->chapters[s->nb_chapters]);
