libavcodec/on2avc.c:806: error: Null Dereference
  pointer `&gb->buffer` last assigned on line 805 could be null and is dereferenced by call to `get_bits1()` at line 806, column 9.

libavcodec/on2avc.c:799:1: start of procedure on2avc_decode_subframe()
797. }
798. 
799. static int on2avc_decode_subframe(On2AVCContext *c, const uint8_t *buf,
     ^
800.                                   int buf_size, AVFrame *dst, int offset)
801. {

libavcodec/on2avc.c:805:5: 
803.     int i, ret;
804. 
805.     init_get_bits(&gb, buf, buf_size * 8);
         ^
806.     if (get_bits1(&gb)) {
807.         av_log(c->avctx, AV_LOG_ERROR, "enh bit set\n");

libavcodec/get_bits.h:384:1: start of procedure init_get_bits()
  382.  * @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
  383.  */
  384. static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
       ^
  385.                                 int bit_size)
  386. {

libavcodec/get_bits.h:388:5: 
  386. {
  387.     int buffer_size;
  388.     int ret = 0;
           ^
  389. 
  390.     if (bit_size > INT_MAX - 7 || bit_size < 0 || !buffer) {

libavcodec/get_bits.h:390:9: Taking true branch
  388.     int ret = 0;
  389. 
  390.     if (bit_size > INT_MAX - 7 || bit_size < 0 || !buffer) {
               ^
  391.         bit_size    = 0;
  392.         buffer      = NULL;

libavcodec/get_bits.h:391:9: 
  389. 
  390.     if (bit_size > INT_MAX - 7 || bit_size < 0 || !buffer) {
  391.         bit_size    = 0;
               ^
  392.         buffer      = NULL;
  393.         ret         = AVERROR_INVALIDDATA;

libavcodec/get_bits.h:392:9: 
  390.     if (bit_size > INT_MAX - 7 || bit_size < 0 || !buffer) {
  391.         bit_size    = 0;
  392.         buffer      = NULL;
               ^
  393.         ret         = AVERROR_INVALIDDATA;
  394.     }

libavcodec/get_bits.h:393:9: 
  391.         bit_size    = 0;
  392.         buffer      = NULL;
  393.         ret         = AVERROR_INVALIDDATA;
               ^
  394.     }
  395. 

libavcodec/get_bits.h:396:5: 
  394.     }
  395. 
  396.     buffer_size = (bit_size + 7) >> 3;
           ^
  397. 
  398.     s->buffer             = buffer;

libavcodec/get_bits.h:398:5: 
  396.     buffer_size = (bit_size + 7) >> 3;
  397. 
  398.     s->buffer             = buffer;
           ^
  399.     s->size_in_bits       = bit_size;
  400. #if !UNCHECKED_BITSTREAM_READER

libavcodec/get_bits.h:399:5: 
  397. 
  398.     s->buffer             = buffer;
  399.     s->size_in_bits       = bit_size;
           ^
  400. #if !UNCHECKED_BITSTREAM_READER
  401.     s->size_in_bits_plus8 = bit_size + 8;

libavcodec/get_bits.h:401:5: 
  399.     s->size_in_bits       = bit_size;
  400. #if !UNCHECKED_BITSTREAM_READER
  401.     s->size_in_bits_plus8 = bit_size + 8;
           ^
  402. #endif
  403.     s->buffer_end         = buffer + buffer_size;

libavcodec/get_bits.h:403:5: 
  401.     s->size_in_bits_plus8 = bit_size + 8;
  402. #endif
  403.     s->buffer_end         = buffer + buffer_size;
           ^
  404.     s->index              = 0;
  405. 

libavcodec/get_bits.h:404:5: 
  402. #endif
  403.     s->buffer_end         = buffer + buffer_size;
  404.     s->index              = 0;
           ^
  405. 
  406.     return ret;

libavcodec/get_bits.h:406:5: 
  404.     s->index              = 0;
  405. 
  406.     return ret;
           ^
  407. }
  408. 

libavcodec/get_bits.h:407:1: return from a call to init_get_bits
  405. 
  406.     return ret;
  407. }
       ^
  408. 
  409. /**

libavcodec/on2avc.c:806:9: 
804. 
805.     init_get_bits(&gb, buf, buf_size * 8);
806.     if (get_bits1(&gb)) {
             ^
807.         av_log(c->avctx, AV_LOG_ERROR, "enh bit set\n");
808.         return AVERROR_INVALIDDATA;

libavcodec/get_bits.h:280:1: start of procedure get_bits1()
  278. }
  279. 
  280. static inline unsigned int get_bits1(GetBitContext *s)
       ^
  281. {
  282.     unsigned int index = s->index;

libavcodec/get_bits.h:282:5: 
  280. static inline unsigned int get_bits1(GetBitContext *s)
  281. {
  282.     unsigned int index = s->index;
           ^
  283.     uint8_t result     = s->buffer[index >> 3];
  284. #ifdef BITSTREAM_READER_LE

libavcodec/get_bits.h:283:5: 
  281. {
  282.     unsigned int index = s->index;
  283.     uint8_t result     = s->buffer[index >> 3];
           ^
  284. #ifdef BITSTREAM_READER_LE
  285.     result >>= index & 7;
