libavfilter/vf_hflip.c:81: error: Null Dereference
  pointer `pix_desc` last assigned on line 78 could be null and is dereferenced at line 81, column 15.

libavfilter/vf_hflip.c:75:1: start of procedure config_props()
73. }
74. 
75. static int config_props(AVFilterLink *inlink)
    ^
76. {
77.     FlipContext *s = inlink->dst->priv;

libavfilter/vf_hflip.c:77:5: 
75. static int config_props(AVFilterLink *inlink)
76. {
77.     FlipContext *s = inlink->dst->priv;
        ^
78.     const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
79. 

libavfilter/vf_hflip.c:78:5: 
76. {
77.     FlipContext *s = inlink->dst->priv;
78.     const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
        ^
79. 
80.     av_image_fill_max_pixsteps(s->max_step, NULL, pix_desc);

libavutil/pixdesc.c:1464:1: start of procedure av_pix_fmt_desc_get()
  1462. }
  1463. 
  1464. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
        ^
  1465. {
  1466.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)

libavutil/pixdesc.c:1466:9: Taking false branch
  1464. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1465. {
  1466.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                ^
  1467.         return NULL;
  1468.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1466:24: Taking true branch
  1464. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1465. {
  1466.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                               ^
  1467.         return NULL;
  1468.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1467:9: 
  1465. {
  1466.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
  1467.         return NULL;
                ^
  1468.     return &av_pix_fmt_descriptors[pix_fmt];
  1469. }

libavutil/pixdesc.c:1469:1: return from a call to av_pix_fmt_desc_get
  1467.         return NULL;
  1468.     return &av_pix_fmt_descriptors[pix_fmt];
  1469. }
        ^
  1470. 
  1471. const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)

libavfilter/vf_hflip.c:80:5: Skipping av_image_fill_max_pixsteps(): empty list of specs
78.     const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
79. 
80.     av_image_fill_max_pixsteps(s->max_step, NULL, pix_desc);
        ^
81.     s->hsub = pix_desc->log2_chroma_w;
82.     s->vsub = pix_desc->log2_chroma_h;

libavfilter/vf_hflip.c:81:5: 
79. 
80.     av_image_fill_max_pixsteps(s->max_step, NULL, pix_desc);
81.     s->hsub = pix_desc->log2_chroma_w;
        ^
82.     s->vsub = pix_desc->log2_chroma_h;
83. 

static int config_props(AVFilterLink *inlink)
{
    FlipContext *s = inlink->dst->priv;
    const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
    av_image_fill_max_pixsteps(s->max_step, NULL, pix_desc);
    s->hsub = pix_desc->log2_chroma_w;
    s->vsub = pix_desc->log2_chroma_h;
    return 0;
}
['static int config_props(AVFilterLink *inlink)\n{\n    FlipContext *s = inlink->dst->priv;\n    const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);\n    av_image_fill_max_pixsteps(s->max_step, NULL, pix_desc);\n    s->hsub = pix_desc->log2_chroma_w;\n    s->vsub = pix_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}']