libavcodec/magicyuv.c:369: error: Uninitialized Value
  The value read from first_offset was never initialized.

libavcodec/magicyuv.c:369:5: 
367.     bytestream2_skip(&gbyte, s->nb_slices * s->planes);
368. 
369.     table_size = header_size + first_offset - bytestream2_tell(&gbyte);
         ^
370.     if (table_size < 2)
371.         return AVERROR_INVALIDDATA;
