libavformat/movenc.c:1083: error: Null Dereference
  pointer `hdlr_type` last assigned on line 1054 could be null and is dereferenced at line 1083, column 5.

libavformat/movenc.c:1052:1: start of procedure mov_write_hdlr_tag()
1050. }
1051. 
1052. static int mov_write_hdlr_tag(AVIOContext *pb, MOVTrack *track)
      ^
1053. {
1054.     const char *hdlr, *descr = NULL, *hdlr_type = NULL;

libavformat/movenc.c:1054:5: 
1052. static int mov_write_hdlr_tag(AVIOContext *pb, MOVTrack *track)
1053. {
1054.     const char *hdlr, *descr = NULL, *hdlr_type = NULL;
          ^
1055.     int64_t pos = url_ftell(pb);
1056. 

libavformat/movenc.c:1055:5: 
1053. {
1054.     const char *hdlr, *descr = NULL, *hdlr_type = NULL;
1055.     int64_t pos = url_ftell(pb);
          ^
1056. 
1057.     if (!track) { /* no media --> data handler */

libavformat/aviobuf.c:242:1: start of procedure url_ftell()
  240. }
  241. 
  242. int64_t url_ftell(AVIOContext *s)
       ^
  243. {
  244.     return url_fseek(s, 0, SEEK_CUR);

libavformat/aviobuf.c:244:5: Skipping url_fseek(): empty list of specs
  242. int64_t url_ftell(AVIOContext *s)
  243. {
  244.     return url_fseek(s, 0, SEEK_CUR);
           ^
  245. }
  246. 

libavformat/aviobuf.c:245:1: return from a call to url_ftell
  243. {
  244.     return url_fseek(s, 0, SEEK_CUR);
  245. }
       ^
  246. 
  247. int64_t url_fsize(AVIOContext *s)

libavformat/movenc.c:1057:10: Taking false branch
1055.     int64_t pos = url_ftell(pb);
1056. 
1057.     if (!track) { /* no media --> data handler */
               ^
1058.         hdlr = "dhlr";
1059.         hdlr_type = "url ";

libavformat/movenc.c:1062:17: Condition is false
1060.         descr = "DataHandler";
1061.     } else {
1062.         hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
                      ^
1063.         if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1064.             hdlr_type = "vide";

libavformat/movenc.c:1062:16: 
1060.         descr = "DataHandler";
1061.     } else {
1062.         hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
                     ^
1063.         if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1064.             hdlr_type = "vide";

libavformat/movenc.c:1062:9: 
1060.         descr = "DataHandler";
1061.     } else {
1062.         hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
              ^
1063.         if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1064.             hdlr_type = "vide";

libavformat/movenc.c:1063:13: Taking false branch
1061.     } else {
1062.         hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
1063.         if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
                  ^
1064.             hdlr_type = "vide";
1065.             descr = "VideoHandler";

libavformat/movenc.c:1066:20: Taking false branch
1064.             hdlr_type = "vide";
1065.             descr = "VideoHandler";
1066.         } else if (track->enc->codec_type == AVMEDIA_TYPE_AUDIO) {
                         ^
1067.             hdlr_type = "soun";
1068.             descr = "SoundHandler";

libavformat/movenc.c:1069:20: Taking false branch
1067.             hdlr_type = "soun";
1068.             descr = "SoundHandler";
1069.         } else if (track->enc->codec_type == AVMEDIA_TYPE_SUBTITLE) {
                         ^
1070.             if (track->tag == MKTAG('t','x','3','g')) hdlr_type = "sbtl";
1071.             else                                      hdlr_type = "text";

libavformat/movenc.c:1073:20: Taking false branch
1071.             else                                      hdlr_type = "text";
1072.             descr = "SubtitleHandler";
1073.         } else if (track->enc->codec_tag == MKTAG('r','t','p',' ')) {
                         ^
1074.             hdlr_type = "hint";
1075.             descr = "HintHandler";

libavformat/movenc.c:1079:5: Skipping avio_wb32(): empty list of specs
1077.     }
1078. 
1079.     avio_wb32(pb, 0); /* size */
          ^
1080.     ffio_wfourcc(pb, "hdlr");
1081.     avio_wb32(pb, 0); /* Version & flags */

libavformat/movenc.c:1080:5: Skipping avio_wl32(): empty list of specs
1078. 
1079.     avio_wb32(pb, 0); /* size */
1080.     ffio_wfourcc(pb, "hdlr");
          ^
1081.     avio_wb32(pb, 0); /* Version & flags */
1082.     avio_write(pb, hdlr, 4); /* handler */

libavformat/movenc.c:1081:5: Skipping avio_wb32(): empty list of specs
1079.     avio_wb32(pb, 0); /* size */
1080.     ffio_wfourcc(pb, "hdlr");
1081.     avio_wb32(pb, 0); /* Version & flags */
          ^
1082.     avio_write(pb, hdlr, 4); /* handler */
1083.     ffio_wfourcc(pb, hdlr_type); /* handler type */

libavformat/movenc.c:1082:5: Skipping avio_write(): empty list of specs
1080.     ffio_wfourcc(pb, "hdlr");
1081.     avio_wb32(pb, 0); /* Version & flags */
1082.     avio_write(pb, hdlr, 4); /* handler */
          ^
1083.     ffio_wfourcc(pb, hdlr_type); /* handler type */
1084.     avio_wb32(pb ,0); /* reserved */

libavformat/movenc.c:1083:5: 
1081.     avio_wb32(pb, 0); /* Version & flags */
1082.     avio_write(pb, hdlr, 4); /* handler */
1083.     ffio_wfourcc(pb, hdlr_type); /* handler type */
          ^
1084.     avio_wb32(pb ,0); /* reserved */
1085.     avio_wb32(pb ,0); /* reserved */
