libavformat/movenc.c:1094: error: Null Dereference
  pointer `hdlr_type` last assigned on line 1065 could be null and is dereferenced at line 1094, column 5.

libavformat/movenc.c:1063:1: start of procedure mov_write_hdlr_tag()
1061. }
1062. 
1063. static int mov_write_hdlr_tag(AVIOContext *pb, MOVTrack *track)
      ^
1064. {
1065.     const char *hdlr, *descr = NULL, *hdlr_type = NULL;

libavformat/movenc.c:1065:5: 
1063. static int mov_write_hdlr_tag(AVIOContext *pb, MOVTrack *track)
1064. {
1065.     const char *hdlr, *descr = NULL, *hdlr_type = NULL;
          ^
1066.     int64_t pos = url_ftell(pb);
1067. 

libavformat/movenc.c:1066:5: 
1064. {
1065.     const char *hdlr, *descr = NULL, *hdlr_type = NULL;
1066.     int64_t pos = url_ftell(pb);
          ^
1067. 
1068.     if (!track) { /* no media --> data handler */

libavformat/aviobuf.c:244:1: start of procedure url_ftell()
  242. #endif
  243. 
  244. int64_t url_ftell(AVIOContext *s)
       ^
  245. {
  246.     return avio_seek(s, 0, SEEK_CUR);

libavformat/aviobuf.c:246:5: Skipping avio_seek(): empty list of specs
  244. int64_t url_ftell(AVIOContext *s)
  245. {
  246.     return avio_seek(s, 0, SEEK_CUR);
           ^
  247. }
  248. 

libavformat/aviobuf.c:247:1: return from a call to url_ftell
  245. {
  246.     return avio_seek(s, 0, SEEK_CUR);
  247. }
       ^
  248. 
  249. int64_t url_fsize(AVIOContext *s)

libavformat/movenc.c:1068:10: Taking false branch
1066.     int64_t pos = url_ftell(pb);
1067. 
1068.     if (!track) { /* no media --> data handler */
               ^
1069.         hdlr = "dhlr";
1070.         hdlr_type = "url ";

libavformat/movenc.c:1073:17: Condition is false
1071.         descr = "DataHandler";
1072.     } else {
1073.         hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
                      ^
1074.         if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1075.             hdlr_type = "vide";

libavformat/movenc.c:1073:16: 
1071.         descr = "DataHandler";
1072.     } else {
1073.         hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
                     ^
1074.         if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1075.             hdlr_type = "vide";

libavformat/movenc.c:1073:9: 
1071.         descr = "DataHandler";
1072.     } else {
1073.         hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
              ^
1074.         if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1075.             hdlr_type = "vide";

libavformat/movenc.c:1074:13: Taking false branch
1072.     } else {
1073.         hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
1074.         if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
                  ^
1075.             hdlr_type = "vide";
1076.             descr = "VideoHandler";

libavformat/movenc.c:1077:20: Taking false branch
1075.             hdlr_type = "vide";
1076.             descr = "VideoHandler";
1077.         } else if (track->enc->codec_type == AVMEDIA_TYPE_AUDIO) {
                         ^
1078.             hdlr_type = "soun";
1079.             descr = "SoundHandler";

libavformat/movenc.c:1080:20: Taking false branch
1078.             hdlr_type = "soun";
1079.             descr = "SoundHandler";
1080.         } else if (track->enc->codec_type == AVMEDIA_TYPE_SUBTITLE) {
                         ^
1081.             if (track->tag == MKTAG('t','x','3','g')) hdlr_type = "sbtl";
1082.             else                                      hdlr_type = "text";

libavformat/movenc.c:1084:20: Taking false branch
1082.             else                                      hdlr_type = "text";
1083.             descr = "SubtitleHandler";
1084.         } else if (track->enc->codec_tag == MKTAG('r','t','p',' ')) {
                         ^
1085.             hdlr_type = "hint";
1086.             descr = "HintHandler";

libavformat/movenc.c:1090:5: Skipping avio_wb32(): empty list of specs
1088.     }
1089. 
1090.     avio_wb32(pb, 0); /* size */
          ^
1091.     ffio_wfourcc(pb, "hdlr");
1092.     avio_wb32(pb, 0); /* Version & flags */

libavformat/movenc.c:1091:5: Skipping avio_wl32(): empty list of specs
1089. 
1090.     avio_wb32(pb, 0); /* size */
1091.     ffio_wfourcc(pb, "hdlr");
          ^
1092.     avio_wb32(pb, 0); /* Version & flags */
1093.     avio_write(pb, hdlr, 4); /* handler */

libavformat/movenc.c:1092:5: Skipping avio_wb32(): empty list of specs
1090.     avio_wb32(pb, 0); /* size */
1091.     ffio_wfourcc(pb, "hdlr");
1092.     avio_wb32(pb, 0); /* Version & flags */
          ^
1093.     avio_write(pb, hdlr, 4); /* handler */
1094.     ffio_wfourcc(pb, hdlr_type); /* handler type */

libavformat/movenc.c:1093:5: Skipping avio_write(): empty list of specs
1091.     ffio_wfourcc(pb, "hdlr");
1092.     avio_wb32(pb, 0); /* Version & flags */
1093.     avio_write(pb, hdlr, 4); /* handler */
          ^
1094.     ffio_wfourcc(pb, hdlr_type); /* handler type */
1095.     avio_wb32(pb ,0); /* reserved */

libavformat/movenc.c:1094:5: 
1092.     avio_wb32(pb, 0); /* Version & flags */
1093.     avio_write(pb, hdlr, 4); /* handler */
1094.     ffio_wfourcc(pb, hdlr_type); /* handler type */
          ^
1095.     avio_wb32(pb ,0); /* reserved */
1096.     avio_wb32(pb ,0); /* reserved */

static int mov_write_hdlr_tag(AVIOContext *pb, MOVTrack *track)
{
    const char *hdlr, *descr = NULL, *hdlr_type = NULL;
    int64_t pos = url_ftell(pb);
    if (!track) {
        hdlr = "dhlr";
        hdlr_type = "url ";
        descr = "DataHandler";
    } else {
        hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
        if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
            hdlr_type = "vide";
            descr = "VideoHandler";
        } else if (track->enc->codec_type == AVMEDIA_TYPE_AUDIO) {
            hdlr_type = "soun";
            descr = "SoundHandler";
        } else if (track->enc->codec_type == AVMEDIA_TYPE_SUBTITLE) {
            if (track->tag == MKTAG('t','x','3','g')) hdlr_type = "sbtl";
            else                                      hdlr_type = "text";
            descr = "SubtitleHandler";
        } else if (track->enc->codec_tag == MKTAG('r','t','p',' ')) {
            hdlr_type = "hint";
            descr = "HintHandler";
        }
    }
    avio_wb32(pb, 0);
    ffio_wfourcc(pb, "hdlr");
    avio_wb32(pb, 0);
    avio_write(pb, hdlr, 4);
    ffio_wfourcc(pb, hdlr_type);
    avio_wb32(pb ,0);
    avio_wb32(pb ,0);
    avio_wb32(pb ,0);
    if (!track || track->mode == MODE_MOV)
        avio_w8(pb, strlen(descr));
    avio_write(pb, descr, strlen(descr));
    if (track && track->mode != MODE_MOV)
        avio_w8(pb, 0);
    return updateSize(pb, pos);
}
['static int mov_write_hdlr_tag(AVIOContext *pb, MOVTrack *track)\n{\n    const char *hdlr, *descr = NULL, *hdlr_type = NULL;\n    int64_t pos = url_ftell(pb);\n    if (!track) {\n        hdlr = "dhlr";\n        hdlr_type = "url ";\n        descr = "DataHandler";\n    } else {\n        hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\\0\\0\\0\\0";\n        if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {\n            hdlr_type = "vide";\n            descr = "VideoHandler";\n        } else if (track->enc->codec_type == AVMEDIA_TYPE_AUDIO) {\n            hdlr_type = "soun";\n            descr = "SoundHandler";\n        } else if (track->enc->codec_type == AVMEDIA_TYPE_SUBTITLE) {\n            if (track->tag == MKTAG(\'t\',\'x\',\'3\',\'g\')) hdlr_type = "sbtl";\n            else                                      hdlr_type = "text";\n            descr = "SubtitleHandler";\n        } else if (track->enc->codec_tag == MKTAG(\'r\',\'t\',\'p\',\' \')) {\n            hdlr_type = "hint";\n            descr = "HintHandler";\n        }\n    }\n    avio_wb32(pb, 0);\n    ffio_wfourcc(pb, "hdlr");\n    avio_wb32(pb, 0);\n    avio_write(pb, hdlr, 4);\n    ffio_wfourcc(pb, hdlr_type);\n    avio_wb32(pb ,0);\n    avio_wb32(pb ,0);\n    avio_wb32(pb ,0);\n    if (!track || track->mode == MODE_MOV)\n        avio_w8(pb, strlen(descr));\n    avio_write(pb, descr, strlen(descr));\n    if (track && track->mode != MODE_MOV)\n        avio_w8(pb, 0);\n    return updateSize(pb, pos);\n}', 'int64_t url_ftell(AVIOContext *s)\n{\n    return avio_seek(s, 0, SEEK_CUR);\n}']