libavcodec/ffv1enc.c:922: error: Buffer Overrun L3
  Offset: [-1, +oo] (⇐ [0, +oo] + -1) Size: 3 by call to `encode_rgb_frame`.

libavcodec/ffv1enc.c:878:5: Assignment
876.     FFV1Context *fs  = *(void **)arg;
877.     FFV1Context *f   = fs->avctx->priv_data;
878.     int width        = fs->slice_width;
         ^
879.     int height       = fs->slice_height;
880.     int x            = fs->slice_x;

libavcodec/ffv1enc.c:922:9: Call
920.                                      p->data[1] + ps * x + y * p->linesize[1],
921.                                      p->data[2] + ps * x + y * p->linesize[2] };
922.         encode_rgb_frame(fs, planes, width, height, p->linesize);
             ^
923.     }
924.     emms_c();

libavcodec/ffv1enc.c:296:1: Array declaration
  294. }
  295. 
  296. static void encode_rgb_frame(FFV1Context *s, const uint8_t *src[3],
       ^
  297.                              int w, int h, const int stride[3])
  298. {

libavcodec/ffv1enc.c:349:17: Call
  347.             sample[p][1][w]  = sample[p][1][w - 1];
  348.             if (lbd)
  349.                 encode_line(s, w, sample[p], (p + 1) / 2, 9);
                       ^
  350.             else
  351.                 encode_line(s, w, sample[p], (p + 1) / 2, bits + 1);

libavcodec/ffv1enc.c:170:1: Parameter `w`
    168. }
    169. 
    170. static av_always_inline int encode_line(FFV1Context *s, int w,
         ^
    171.                                         int16_t *sample[3],
    172.                                         int plane_index, int bits)

libavcodec/ffv1enc.c:196:19: Call
    194.         int diff, context;
    195. 
    196.         context = get_context(p, sample[0] + x, sample[1] + x, sample[2] + x);
                           ^
    197.         diff    = sample[0][x] - predict(sample[0] + x, sample[1] + x);
    198. 

libavcodec/ffv1.h:140:1: <Length trace>
138. }
139. 
140. static inline int get_context(PlaneContext *p, int16_t *src,
     ^
141.                               int16_t *last, int16_t *last2)
142. {

libavcodec/ffv1.h:140:1: Parameter `*last`
      138. }
      139. 
      140. static inline int get_context(PlaneContext *p, int16_t *src,
           ^
      141.                               int16_t *last, int16_t *last2)
      142. {

libavcodec/ffv1.h:143:20: Array access: Offset: [-1, +oo] (⇐ [0, +oo] + -1) Size: 3 by call to `encode_rgb_frame` 
      141.                               int16_t *last, int16_t *last2)
      142. {
      143.     const int LT = last[-1];
                              ^
      144.     const int T  = last[0];
      145.     const int RT = last[1];
