libswscale/swscale.c:94: error: Null Dereference
  pointer `desc` last assigned on line 90 could be null and is dereferenced at line 94, column 27.

libswscale/swscale.c:86:1: start of procedure hScale16To19_c()
84. 
85. 
86. static void hScale16To19_c(SwsContext *c, int16_t *_dst, int dstW,
    ^
87.                            const uint8_t *_src, const int16_t *filter,
88.                            const int32_t *filterPos, int filterSize)

libswscale/swscale.c:90:5: 
88.                            const int32_t *filterPos, int filterSize)
89. {
90.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(c->srcFormat);
        ^
91.     int i;
92.     int32_t *dst        = (int32_t *) _dst;

libavutil/pixdesc.c:1685:1: start of procedure av_pix_fmt_desc_get()
  1683. }
  1684. 
  1685. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
        ^
  1686. {
  1687.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)

libavutil/pixdesc.c:1687:9: Taking false branch
  1685. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1686. {
  1687.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                ^
  1688.         return NULL;
  1689.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1687:24: Taking true branch
  1685. const AVPixFmtDescriptor *av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
  1686. {
  1687.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
                               ^
  1688.         return NULL;
  1689.     return &av_pix_fmt_descriptors[pix_fmt];

libavutil/pixdesc.c:1688:9: 
  1686. {
  1687.     if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB)
  1688.         return NULL;
                ^
  1689.     return &av_pix_fmt_descriptors[pix_fmt];
  1690. }

libavutil/pixdesc.c:1690:1: return from a call to av_pix_fmt_desc_get
  1688.         return NULL;
  1689.     return &av_pix_fmt_descriptors[pix_fmt];
  1690. }
        ^
  1691. 
  1692. const AVPixFmtDescriptor *av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)

libswscale/swscale.c:92:5: 
90.     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(c->srcFormat);
91.     int i;
92.     int32_t *dst        = (int32_t *) _dst;
        ^
93.     const uint16_t *src = (const uint16_t *) _src;
94.     int bits            = desc->comp[0].depth - 1;

libswscale/swscale.c:93:5: 
91.     int i;
92.     int32_t *dst        = (int32_t *) _dst;
93.     const uint16_t *src = (const uint16_t *) _src;
        ^
94.     int bits            = desc->comp[0].depth - 1;
95.     int sh              = bits - 4;

libswscale/swscale.c:94:5: 
92.     int32_t *dst        = (int32_t *) _dst;
93.     const uint16_t *src = (const uint16_t *) _src;
94.     int bits            = desc->comp[0].depth - 1;
        ^
95.     int sh              = bits - 4;
96. 

static void hScale16To19_c(SwsContext *c, int16_t *_dst, int dstW,
                           const uint8_t *_src, const int16_t *filter,
                           const int32_t *filterPos, int filterSize)
{
    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(c->srcFormat);
    int i;
    int32_t *dst        = (int32_t *) _dst;
    const uint16_t *src = (const uint16_t *) _src;
    int bits            = desc->comp[0].depth - 1;
    int sh              = bits - 4;
    for (i = 0; i < dstW; i++) {
        int j;
        int srcPos = filterPos[i];
        int val    = 0;
        for (j = 0; j < filterSize; j++) {
            val += src[srcPos + j] * filter[filterSize * i + j];
        }
        dst[i] = FFMIN(val >> sh, (1 << 19) - 1);
    }
}
['static void hScale16To19_c(SwsContext *c, int16_t *_dst, int dstW,\n                           const uint8_t *_src, const int16_t *filter,\n                           const int32_t *filterPos, int filterSize)\n{\n    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(c->srcFormat);\n    int i;\n    int32_t *dst        = (int32_t *) _dst;\n    const uint16_t *src = (const uint16_t *) _src;\n    int bits            = desc->comp[0].depth - 1;\n    int sh              = bits - 4;\n    for (i = 0; i < dstW; i++) {\n        int j;\n        int srcPos = filterPos[i];\n        int val    = 0;\n        for (j = 0; j < filterSize; j++) {\n            val += src[srcPos + j] * filter[filterSize * i + j];\n        }\n        dst[i] = FFMIN(val >> sh, (1 << 19) - 1);\n    }\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}']