libavformat/movenc.c:2169: error: Null Dereference
  pointer `pkt.data` last assigned on line 2168 could be null and is dereferenced at line 2169, column 13.

libavformat/movenc.c:2144:1: start of procedure mov_create_chapter_track()
2142. // QuickTime chapters involve an additional text track with the chapter names
2143. // as samples, and a tref pointing from the other tracks to the chapter one.
2144. static void mov_create_chapter_track(AVFormatContext *s, int tracknum)
      ^
2145. {
2146.     MOVMuxContext *mov = s->priv_data;

libavformat/movenc.c:2146:5: 
2144. static void mov_create_chapter_track(AVFormatContext *s, int tracknum)
2145. {
2146.     MOVMuxContext *mov = s->priv_data;
          ^
2147.     MOVTrack *track = &mov->tracks[tracknum];
2148.     AVPacket pkt = { .stream_index = tracknum, .flags = AV_PKT_FLAG_KEY };

libavformat/movenc.c:2147:5: 
2145. {
2146.     MOVMuxContext *mov = s->priv_data;
2147.     MOVTrack *track = &mov->tracks[tracknum];
          ^
2148.     AVPacket pkt = { .stream_index = tracknum, .flags = AV_PKT_FLAG_KEY };
2149.     int i, len;

libavformat/movenc.c:2148:5: 
2146.     MOVMuxContext *mov = s->priv_data;
2147.     MOVTrack *track = &mov->tracks[tracknum];
2148.     AVPacket pkt = { .stream_index = tracknum, .flags = AV_PKT_FLAG_KEY };
          ^
2149.     int i, len;
2150. 

libavformat/movenc.c:2151:5: 
2149.     int i, len;
2150. 
2151.     track->mode = mov->mode;
          ^
2152.     track->tag = MKTAG('t','e','x','t');
2153.     track->timescale = MOV_TIMESCALE;

libavformat/movenc.c:2152:5: 
2150. 
2151.     track->mode = mov->mode;
2152.     track->tag = MKTAG('t','e','x','t');
          ^
2153.     track->timescale = MOV_TIMESCALE;
2154.     track->enc = avcodec_alloc_context3(NULL);

libavformat/movenc.c:2153:5: 
2151.     track->mode = mov->mode;
2152.     track->tag = MKTAG('t','e','x','t');
2153.     track->timescale = MOV_TIMESCALE;
          ^
2154.     track->enc = avcodec_alloc_context3(NULL);
2155.     track->enc->codec_type = AVMEDIA_TYPE_SUBTITLE;

libavformat/movenc.c:2154:5: 
2152.     track->tag = MKTAG('t','e','x','t');
2153.     track->timescale = MOV_TIMESCALE;
2154.     track->enc = avcodec_alloc_context3(NULL);
          ^
2155.     track->enc->codec_type = AVMEDIA_TYPE_SUBTITLE;
2156. 

libavcodec/options.c:599:1: start of procedure avcodec_alloc_context3()
  597. }
  598. 
  599. AVCodecContext *avcodec_alloc_context3(AVCodec *codec){
       ^
  600.     AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
  601. 

libavcodec/options.c:600:5: 
  598. 
  599. AVCodecContext *avcodec_alloc_context3(AVCodec *codec){
  600.     AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
           ^
  601. 
  602.     if(avctx==NULL) return NULL;

libavutil/mem.c:64:1: start of procedure av_malloc()
    62.    linker will do it automatically. */
    63. 
    64. void *av_malloc(size_t size)
        ^
    65. {
    66.     void *ptr = NULL;

libavutil/mem.c:66:5: 
    64. void *av_malloc(size_t size)
    65. {
    66.     void *ptr = NULL;
            ^
    67. #if CONFIG_MEMALIGN_HACK
    68.     long diff;

libavutil/mem.c:72:8: Taking false branch
    70. 
    71.     /* let's disallow possible ambiguous cases */
    72.     if(size > (INT_MAX-32) )
               ^
    73.         return NULL;
    74. 

libavutil/mem.c:83:9: Taking false branch
    81.     ((char*)ptr)[-1]= diff;
    82. #elif HAVE_POSIX_MEMALIGN
    83.     if (posix_memalign(&ptr,32,size))
                ^
    84.         ptr = NULL;
    85. #elif HAVE_MEMALIGN

libavutil/mem.c:114:5: 
    112.     ptr = malloc(size);
    113. #endif
    114.     return ptr;
             ^
    115. }
    116. 

libavutil/mem.c:115:1: return from a call to av_malloc
    113. #endif
    114.     return ptr;
    115. }
         ^
    116. 
    117. void *av_realloc(void *ptr, size_t size)

libavcodec/options.c:602:8: Taking false branch
  600.     AVCodecContext *avctx= av_malloc(sizeof(AVCodecContext));
  601. 
  602.     if(avctx==NULL) return NULL;
              ^
  603. 
  604.     if(avcodec_get_context_defaults3(avctx, codec) < 0){

libavcodec/options.c:604:8: Taking false branch
  602.     if(avctx==NULL) return NULL;
  603. 
  604.     if(avcodec_get_context_defaults3(avctx, codec) < 0){
              ^
  605.         av_free(avctx);
  606.         return NULL;

libavcodec/options.c:609:5: 
  607.     }
  608. 
  609.     return avctx;
           ^
  610. }
  611. 

libavcodec/options.c:610:1: return from a call to avcodec_alloc_context3
  608. 
  609.     return avctx;
  610. }
       ^
  611. 
  612. #if FF_API_ALLOC_CONTEXT

libavformat/movenc.c:2155:5: 
2153.     track->timescale = MOV_TIMESCALE;
2154.     track->enc = avcodec_alloc_context3(NULL);
2155.     track->enc->codec_type = AVMEDIA_TYPE_SUBTITLE;
          ^
2156. 
2157.     for (i = 0; i < s->nb_chapters; i++) {

libavformat/movenc.c:2157:10: 
2155.     track->enc->codec_type = AVMEDIA_TYPE_SUBTITLE;
2156. 
2157.     for (i = 0; i < s->nb_chapters; i++) {
               ^
2158.         AVChapter *c = s->chapters[i];
2159.         AVDictionaryEntry *t;

libavformat/movenc.c:2157:17: Loop condition is true. Entering loop body
2155.     track->enc->codec_type = AVMEDIA_TYPE_SUBTITLE;
2156. 
2157.     for (i = 0; i < s->nb_chapters; i++) {
                      ^
2158.         AVChapter *c = s->chapters[i];
2159.         AVDictionaryEntry *t;

libavformat/movenc.c:2158:9: 
2156. 
2157.     for (i = 0; i < s->nb_chapters; i++) {
2158.         AVChapter *c = s->chapters[i];
              ^
2159.         AVDictionaryEntry *t;
2160. 

libavformat/movenc.c:2161:9: 
2159.         AVDictionaryEntry *t;
2160. 
2161.         int64_t end = av_rescale_q(c->end, c->time_base, (AVRational){1,MOV_TIMESCALE});
              ^
2162.         pkt.pts = pkt.dts = av_rescale_q(c->start, c->time_base, (AVRational){1,MOV_TIMESCALE});
2163.         pkt.duration = end - pkt.dts;

libavutil/mathematics.c:133:1: start of procedure av_rescale_q()
  131. }
  132. 
  133. int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
       ^
  134.     int64_t b= bq.num * (int64_t)cq.den;
  135.     int64_t c= cq.num * (int64_t)bq.den;

libavutil/mathematics.c:134:5: 
  132. 
  133. int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
  134.     int64_t b= bq.num * (int64_t)cq.den;
           ^
  135.     int64_t c= cq.num * (int64_t)bq.den;
  136.     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);

libavutil/mathematics.c:135:5: 
  133. int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
  134.     int64_t b= bq.num * (int64_t)cq.den;
  135.     int64_t c= cq.num * (int64_t)bq.den;
           ^
  136.     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
  137. }

libavutil/mathematics.c:136:5: Skipping av_rescale_rnd(): empty list of specs
  134.     int64_t b= bq.num * (int64_t)cq.den;
  135.     int64_t c= cq.num * (int64_t)bq.den;
  136.     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
           ^
  137. }
  138. 

libavutil/mathematics.c:137:1: return from a call to av_rescale_q
  135.     int64_t c= cq.num * (int64_t)bq.den;
  136.     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
  137. }
       ^
  138. 
  139. int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b){

libavformat/movenc.c:2162:9: 
2160. 
2161.         int64_t end = av_rescale_q(c->end, c->time_base, (AVRational){1,MOV_TIMESCALE});
2162.         pkt.pts = pkt.dts = av_rescale_q(c->start, c->time_base, (AVRational){1,MOV_TIMESCALE});
              ^
2163.         pkt.duration = end - pkt.dts;
2164. 

libavutil/mathematics.c:133:1: start of procedure av_rescale_q()
  131. }
  132. 
  133. int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
       ^
  134.     int64_t b= bq.num * (int64_t)cq.den;
  135.     int64_t c= cq.num * (int64_t)bq.den;

libavutil/mathematics.c:134:5: 
  132. 
  133. int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
  134.     int64_t b= bq.num * (int64_t)cq.den;
           ^
  135.     int64_t c= cq.num * (int64_t)bq.den;
  136.     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);

libavutil/mathematics.c:135:5: 
  133. int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
  134.     int64_t b= bq.num * (int64_t)cq.den;
  135.     int64_t c= cq.num * (int64_t)bq.den;
           ^
  136.     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
  137. }

libavutil/mathematics.c:136:5: Skipping av_rescale_rnd(): empty list of specs
  134.     int64_t b= bq.num * (int64_t)cq.den;
  135.     int64_t c= cq.num * (int64_t)bq.den;
  136.     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
           ^
  137. }
  138. 

libavutil/mathematics.c:137:1: return from a call to av_rescale_q
  135.     int64_t c= cq.num * (int64_t)bq.den;
  136.     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
  137. }
       ^
  138. 
  139. int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b){

libavformat/movenc.c:2163:9: 
2161.         int64_t end = av_rescale_q(c->end, c->time_base, (AVRational){1,MOV_TIMESCALE});
2162.         pkt.pts = pkt.dts = av_rescale_q(c->start, c->time_base, (AVRational){1,MOV_TIMESCALE});
2163.         pkt.duration = end - pkt.dts;
              ^
2164. 
2165.         if ((t = av_dict_get(c->metadata, "title", NULL, 0))) {

libavformat/movenc.c:2165:14: Taking true branch
2163.         pkt.duration = end - pkt.dts;
2164. 
2165.         if ((t = av_dict_get(c->metadata, "title", NULL, 0))) {
                   ^
2166.             len = strlen(t->value);
2167.             pkt.size = len+2;

libavformat/movenc.c:2166:13: 
2164. 
2165.         if ((t = av_dict_get(c->metadata, "title", NULL, 0))) {
2166.             len = strlen(t->value);
                  ^
2167.             pkt.size = len+2;
2168.             pkt.data = av_malloc(pkt.size);

libavformat/movenc.c:2167:13: 
2165.         if ((t = av_dict_get(c->metadata, "title", NULL, 0))) {
2166.             len = strlen(t->value);
2167.             pkt.size = len+2;
                  ^
2168.             pkt.data = av_malloc(pkt.size);
2169.             AV_WB16(pkt.data, len);

libavformat/movenc.c:2168:13: 
2166.             len = strlen(t->value);
2167.             pkt.size = len+2;
2168.             pkt.data = av_malloc(pkt.size);
                  ^
2169.             AV_WB16(pkt.data, len);
2170.             memcpy(pkt.data+2, t->value, len);

libavutil/mem.c:64:1: start of procedure av_malloc()
  62.    linker will do it automatically. */
  63. 
  64. void *av_malloc(size_t size)
      ^
  65. {
  66.     void *ptr = NULL;

libavutil/mem.c:66:5: 
  64. void *av_malloc(size_t size)
  65. {
  66.     void *ptr = NULL;
          ^
  67. #if CONFIG_MEMALIGN_HACK
  68.     long diff;

libavutil/mem.c:72:8: Taking true branch
  70. 
  71.     /* let's disallow possible ambiguous cases */
  72.     if(size > (INT_MAX-32) )
             ^
  73.         return NULL;
  74. 

libavutil/mem.c:73:9: 
  71.     /* let's disallow possible ambiguous cases */
  72.     if(size > (INT_MAX-32) )
  73.         return NULL;
              ^
  74. 
  75. #if CONFIG_MEMALIGN_HACK

libavutil/mem.c:115:1: return from a call to av_malloc
  113. #endif
  114.     return ptr;
  115. }
       ^
  116. 
  117. void *av_realloc(void *ptr, size_t size)

libavformat/movenc.c:2169:13: 
2167.             pkt.size = len+2;
2168.             pkt.data = av_malloc(pkt.size);
2169.             AV_WB16(pkt.data, len);
                  ^
2170.             memcpy(pkt.data+2, t->value, len);
2171.             ff_mov_write_packet(s, &pkt);

libavutil/bswap.h:58:1: start of procedure av_bswap16()
  56. 
  57. #ifndef av_bswap16
  58. static av_always_inline av_const uint16_t av_bswap16(uint16_t x)
      ^
  59. {
  60.     x= (x>>8) | (x<<8);

libavutil/bswap.h:60:5: 
  58. static av_always_inline av_const uint16_t av_bswap16(uint16_t x)
  59. {
  60.     x= (x>>8) | (x<<8);
          ^
  61.     return x;
  62. }

libavutil/bswap.h:61:5: 
  59. {
  60.     x= (x>>8) | (x<<8);
  61.     return x;
          ^
  62. }
  63. #endif

libavutil/bswap.h:62:1: return from a call to av_bswap16
  60.     x= (x>>8) | (x<<8);
  61.     return x;
  62. }
      ^
  63. #endif
  64. 
