libavcodec/h263.c:419: error: Buffer Overrun L3
  Offset added: 24 Size: [0, +oo].

libavcodec/h263.c:413:1: <Length trace>
411. }
412. 
413. static inline int decide_ac_pred(MpegEncContext * s, DCTELEM block[6][64], int dir[6], uint8_t *st[6], int zigzag_last_index[6])
     ^
414. {
415.     int score= 0;

libavcodec/h263.c:413:1: Parameter `s->block_last_index[*]`
411. }
412. 
413. static inline int decide_ac_pred(MpegEncContext * s, DCTELEM block[6][64], int dir[6], uint8_t *st[6], int zigzag_last_index[6])
     ^
414. {
415.     int score= 0;

libavcodec/h263.c:419:5: Array access: Offset added: 24 Size: [0, +oo]
417.     int8_t * const qscale_table= s->current_picture.qscale_table;
418. 
419.     memcpy(zigzag_last_index, s->block_last_index, sizeof(int)*6);
         ^
420. 
421.     for(n=0; n<6; n++){
