libavcodec/utils.c:253: error: Null Dereference
  pointer `desc` last assigned on line 252 could be null and is dereferenced at line 253, column 24.

libavcodec/utils.c:250:1: start of procedure avcodec_align_dimensions()
248. }
249. 
250. void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height)
     ^
251. {
252.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(s->pix_fmt);

libavcodec/utils.c:252:5: 
250. void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height)
251. {
252.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(s->pix_fmt);
         ^
253.     int chroma_shift = desc->log2_chroma_w;
254.     int linesize_align[AV_NUM_DATA_POINTERS];

libavutil/pixdesc.c:1199:1: start of procedure av_pix_fmt_desc_get()
  1197. }
  1198. 
  1199. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
        ^
  1200. {
  1201.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)

libavutil/pixdesc.c:1201:9: Taking false branch
  1199. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1200. {
  1201.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                ^
  1202.         return NULL;
  1203.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1201:24: Taking true branch
  1199. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1200. {
  1201.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                               ^
  1202.         return NULL;
  1203.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1202:9: 
  1200. {
  1201.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
  1202.         return NULL;
                ^
  1203.     return &av_pix_fmt_descriptors[pix_fmt];
  1204. }

libavutil/pixdesc.c:1204:1: return from a call to av_pix_fmt_desc_get
  1202.         return NULL;
  1203.     return &av_pix_fmt_descriptors[pix_fmt];
  1204. }
        ^
  1205. 
  1206. const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)

libavcodec/utils.c:253:5: 
251. {
252.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(s->pix_fmt);
253.     int chroma_shift = desc->log2_chroma_w;
         ^
254.     int linesize_align[AV_NUM_DATA_POINTERS];
255.     int align;
