libavcodec/avpicture.c:93: error: Null Dereference
  pointer `desc` last assigned on line 87 could be null and is dereferenced at line 93, column 9.

libavcodec/avpicture.c:85:1: start of procedure avpicture_get_size()
83. }
84. 
85. int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height)
    ^
86. {
87.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);

libavcodec/avpicture.c:87:5: 
85. int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height)
86. {
87.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
        ^
88.     AVPicture dummy_pict;
89.     int ret;

libavutil/pixdesc.c:1434:1: start of procedure av_pix_fmt_desc_get()
  1432. }
  1433. 
  1434. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
        ^
  1435. {
  1436.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)

libavutil/pixdesc.c:1436:9: Taking false branch
  1434. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1435. {
  1436.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                ^
  1437.         return NULL;
  1438.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1436:24: Taking true branch
  1434. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1435. {
  1436.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                               ^
  1437.         return NULL;
  1438.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1437:9: 
  1435. {
  1436.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
  1437.         return NULL;
                ^
  1438.     return &av_pix_fmt_descriptors[pix_fmt];
  1439. }

libavutil/pixdesc.c:1439:1: return from a call to av_pix_fmt_desc_get
  1437.         return NULL;
  1438.     return &av_pix_fmt_descriptors[pix_fmt];
  1439. }
        ^
  1440. 
  1441. const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)

libavcodec/avpicture.c:91:9: 
89.     int ret;
90. 
91.     if ((ret = av_image_check_size(width, height, 0, NULL)) < 0)
            ^
92.         return ret;
93.     if (desc->flags & PIX_FMT_PSEUDOPAL)

libavutil/imgutils.c:220:1: start of procedure av_image_check_size()
  218. static const AVClass imgutils_class = { "IMGUTILS", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(ImgUtils, log_offset), offsetof(ImgUtils, log_ctx) };
  219. 
  220. int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
       ^
  221. {
  222.     ImgUtils imgutils = { &imgutils_class, log_offset, log_ctx };

libavutil/imgutils.c:222:5: 
  220. int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
  221. {
  222.     ImgUtils imgutils = { &imgutils_class, log_offset, log_ctx };
           ^
  223. 
  224.     if ((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)

libavutil/imgutils.c:224:9: Taking true branch
  222.     ImgUtils imgutils = { &imgutils_class, log_offset, log_ctx };
  223. 
  224.     if ((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)
               ^
  225.         return 0;
  226. 

libavutil/imgutils.c:224:21: Taking true branch
  222.     ImgUtils imgutils = { &imgutils_class, log_offset, log_ctx };
  223. 
  224.     if ((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)
                           ^
  225.         return 0;
  226. 

libavutil/imgutils.c:224:33: Taking true branch
  222.     ImgUtils imgutils = { &imgutils_class, log_offset, log_ctx };
  223. 
  224.     if ((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)
                                       ^
  225.         return 0;
  226. 

libavutil/imgutils.c:225:9: 
  223. 
  224.     if ((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)
  225.         return 0;
               ^
  226. 
  227.     av_log(&imgutils, AV_LOG_ERROR, "Picture size %ux%u is invalid\n", w, h);

libavutil/imgutils.c:229:1: return from a call to av_image_check_size
  227.     av_log(&imgutils, AV_LOG_ERROR, "Picture size %ux%u is invalid\n", w, h);
  228.     return AVERROR(EINVAL);
  229. }
       ^
  230. 
  231. void av_image_copy_plane(uint8_t       *dst, int dst_linesize,

libavcodec/avpicture.c:91:9: Taking false branch
89.     int ret;
90. 
91.     if ((ret = av_image_check_size(width, height, 0, NULL)) < 0)
            ^
92.         return ret;
93.     if (desc->flags & PIX_FMT_PSEUDOPAL)

libavcodec/avpicture.c:93:9: 
91.     if ((ret = av_image_check_size(width, height, 0, NULL)) < 0)
92.         return ret;
93.     if (desc->flags & PIX_FMT_PSEUDOPAL)
            ^
94.         // do not include palette for these pseudo-paletted formats
95.         return width * height;
