libavcodec/imgconvert.c:61: error: Null Dereference
  pointer `dst_desc` last assigned on line 60 could be null and is dereferenced at line 61, column 34.

libavcodec/imgconvert.c:55:1: start of procedure avcodec_get_pix_fmt_loss()
53. }
54. 
55. int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt,
    ^
56.                              enum AVPixelFormat src_pix_fmt,
57.                              int has_alpha)

libavcodec/imgconvert.c:59:5: 
57.                              int has_alpha)
58. {
59.     const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_pix_fmt);
        ^
60.     const AVPixFmtDescriptor *dst_desc = av_pix_fmt_desc_get(dst_pix_fmt);
61.     int loss, i, nb_components = FFMIN(src_desc->nb_components,

libavutil/pixdesc.c:1686:1: start of procedure av_pix_fmt_desc_get()
  1684. }
  1685. 
  1686. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
        ^
  1687. {
  1688.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)

libavutil/pixdesc.c:1688:9: Taking false branch
  1686. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1687. {
  1688.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                ^
  1689.         return NULL;
  1690.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1688:24: Taking false branch
  1686. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1687. {
  1688.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                               ^
  1689.         return NULL;
  1690.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1690:5: 
  1688.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
  1689.         return NULL;
  1690.     return &av_pix_fmt_descriptors[pix_fmt];
            ^
  1691. }
  1692. 

libavutil/pixdesc.c:1691:1: return from a call to av_pix_fmt_desc_get
  1689.         return NULL;
  1690.     return &av_pix_fmt_descriptors[pix_fmt];
  1691. }
        ^
  1692. 
  1693. const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)

libavcodec/imgconvert.c:60:5: 
58. {
59.     const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_pix_fmt);
60.     const AVPixFmtDescriptor *dst_desc = av_pix_fmt_desc_get(dst_pix_fmt);
        ^
61.     int loss, i, nb_components = FFMIN(src_desc->nb_components,
62.                                        dst_desc->nb_components);

libavutil/pixdesc.c:1686:1: start of procedure av_pix_fmt_desc_get()
  1684. }
  1685. 
  1686. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
        ^
  1687. {
  1688.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)

libavutil/pixdesc.c:1688:9: Taking false branch
  1686. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1687. {
  1688.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                ^
  1689.         return NULL;
  1690.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1688:24: Taking true branch
  1686. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1687. {
  1688.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                               ^
  1689.         return NULL;
  1690.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1689:9: 
  1687. {
  1688.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
  1689.         return NULL;
                ^
  1690.     return &av_pix_fmt_descriptors[pix_fmt];
  1691. }

libavutil/pixdesc.c:1691:1: return from a call to av_pix_fmt_desc_get
  1689.         return NULL;
  1690.     return &av_pix_fmt_descriptors[pix_fmt];
  1691. }
        ^
  1692. 
  1693. const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)

libavcodec/imgconvert.c:61:34: 
59.     const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_pix_fmt);
60.     const AVPixFmtDescriptor *dst_desc = av_pix_fmt_desc_get(dst_pix_fmt);
61.     int loss, i, nb_components = FFMIN(src_desc->nb_components,
                                     ^
62.                                        dst_desc->nb_components);
63. 
