libavfilter/vf_slicify.c:59: error: Null Dereference
  pointer `desc` last assigned on line 57 could be null and is dereferenced at line 59, column 21.

libavfilter/vf_slicify.c:54:1: start of procedure config_props()
52. }
53. 
54. static int config_props(AVFilterLink *link)
    ^
55. {
56.     SliceContext *slice = link->dst->priv;

libavfilter/vf_slicify.c:56:5: 
54. static int config_props(AVFilterLink *link)
55. {
56.     SliceContext *slice = link->dst->priv;
        ^
57.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
58. 

libavfilter/vf_slicify.c:57:5: 
55. {
56.     SliceContext *slice = link->dst->priv;
57.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
        ^
58. 
59.     slice->vshift = desc->log2_chroma_h;

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)

libavfilter/vf_slicify.c:59:5: 
57.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
58. 
59.     slice->vshift = desc->log2_chroma_h;
        ^
60. 
61.     return 0;

static int config_props(AVFilterLink *link)
{
    SliceContext *slice = link->dst->priv;
    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
    slice->vshift = desc->log2_chroma_h;
    return 0;
}
['static int config_props(AVFilterLink *link)\n{\n    SliceContext *slice = link->dst->priv;\n    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);\n    slice->vshift = desc->log2_chroma_h;\n    return 0;\n}', 'const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)\n{\n    if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)\n        return NULL;\n    return &av_pix_fmt_descriptors[pix_fmt];\n}']