libavcodec/imgconvert.c:47: error: Null Dereference
  pointer `src_desc` last assigned on line 45 could be null and is dereferenced at line 47, column 34.

libavcodec/imgconvert.c:41:1: start of procedure avcodec_get_pix_fmt_loss()
39. }
40. 
41. int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt,
    ^
42.                              enum AVPixelFormat src_pix_fmt,
43.                              int has_alpha)

libavcodec/imgconvert.c:45:5: 
43.                              int has_alpha)
44. {
45.     const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_pix_fmt);
        ^
46.     const AVPixFmtDescriptor *dst_desc = av_pix_fmt_desc_get(dst_pix_fmt);
47.     int loss, i, nb_components = FFMIN(src_desc->nb_components,

libavutil/pixdesc.c:1866:1: start of procedure av_pix_fmt_desc_get()
  1864. }
  1865. 
  1866. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
        ^
  1867. {
  1868.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)

libavutil/pixdesc.c:1868:9: Taking false branch
  1866. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1867. {
  1868.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                ^
  1869.         return NULL;
  1870.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1868:24: Taking true branch
  1866. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1867. {
  1868.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                               ^
  1869.         return NULL;
  1870.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1869:9: 
  1867. {
  1868.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
  1869.         return NULL;
                ^
  1870.     return &av_pix_fmt_descriptors[pix_fmt];
  1871. }

libavutil/pixdesc.c:1871:1: return from a call to av_pix_fmt_desc_get
  1869.         return NULL;
  1870.     return &av_pix_fmt_descriptors[pix_fmt];
  1871. }
        ^
  1872. 
  1873. const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)

libavcodec/imgconvert.c:46:5: 
44. {
45.     const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_pix_fmt);
46.     const AVPixFmtDescriptor *dst_desc = av_pix_fmt_desc_get(dst_pix_fmt);
        ^
47.     int loss, i, nb_components = FFMIN(src_desc->nb_components,
48.                                        dst_desc->nb_components);

libavutil/pixdesc.c:1866:1: start of procedure av_pix_fmt_desc_get()
  1864. }
  1865. 
  1866. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
        ^
  1867. {
  1868.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)

libavutil/pixdesc.c:1868:9: Taking false branch
  1866. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1867. {
  1868.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                ^
  1869.         return NULL;
  1870.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1868:24: Taking true branch
  1866. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1867. {
  1868.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                               ^
  1869.         return NULL;
  1870.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1869:9: 
  1867. {
  1868.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
  1869.         return NULL;
                ^
  1870.     return &av_pix_fmt_descriptors[pix_fmt];
  1871. }

libavutil/pixdesc.c:1871:1: return from a call to av_pix_fmt_desc_get
  1869.         return NULL;
  1870.     return &av_pix_fmt_descriptors[pix_fmt];
  1871. }
        ^
  1872. 
  1873. const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)

libavcodec/imgconvert.c:47:34: 
45.     const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_pix_fmt);
46.     const AVPixFmtDescriptor *dst_desc = av_pix_fmt_desc_get(dst_pix_fmt);
47.     int loss, i, nb_components = FFMIN(src_desc->nb_components,
                                     ^
48.                                        dst_desc->nb_components);
49. 
