avconv.c:173: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned32 by call to `avformat_free_context`.

avconv.c:163:9: Call
161.         }
162.         av_freep(&filtergraphs[i]->outputs);
163.         av_freep(&filtergraphs[i]->graph_desc);
             ^
164.         av_freep(&filtergraphs[i]);
165.     }

libavutil/mem.c:155:5: Assignment
  153.     void **ptr = (void **)arg;
  154.     av_free(*ptr);
  155.     *ptr = NULL;
           ^
  156. }
  157. 

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

libavformat/utils.c:2635:1: <LHS trace>
2633. }
2634. 
2635. void avformat_free_context(AVFormatContext *s)
      ^
2636. {
2637.     int i;

libavformat/utils.c:2635:1: Parameter `s->nb_programs`
  2633. }
  2634. 
  2635. void avformat_free_context(AVFormatContext *s)
        ^
  2636. {
  2637.     int i;

libavformat/utils.c:2661:9: Binary operation: ([0, +oo] - 1):unsigned32 by call to `avformat_free_context` 
  2659.         av_free(st);
  2660.     }
  2661.     for(i=s->nb_programs-1; i>=0; i--) {
                ^
  2662.         av_dict_free(&s->programs[i]->metadata);
  2663.         av_freep(&s->programs[i]->stream_index);
