libavformat/flvdec.c:391: error: Uninitialized Value
  The value read from size was never initialized.

libavformat/flvdec.c:391:9: 
389.         st->codec->codec_id == CODEC_ID_H264) {
390.         int type = get_byte(s->pb);
391.         size--;
             ^
392.         if (st->codec->codec_id == CODEC_ID_H264) {
393.             // cts offset ignored because it might to be signed
