libavformat/rtsp.c:2429: error: Uninitialized Value
  The value read from payload_type was never initialized.

libavformat/rtsp.c:2429:9: 
2427. 
2428.     if (ff_rtp_get_codec_info(par, payload_type)) {
2429.         av_log(s, AV_LOG_ERROR, "Unable to receive RTP payload type %d "
              ^
2430.                                 "without an SDP file describing it\n",
2431.                                  payload_type);
