libavcodec/sonic.c:770: error: Null Dereference
  pointer `&gb->buffer` last assigned on line 768 could be null and is dereferenced by call to `get_bits()` at line 770, column 15.

libavcodec/sonic.c:753:1: start of procedure sonic_decode_init()
751. 
752. #if CONFIG_SONIC_DECODER
753. static av_cold int sonic_decode_init(AVCodecContext *avctx)
     ^
754. {
755.     SonicContext *s = avctx->priv_data;

libavcodec/sonic.c:755:5: 
753. static av_cold int sonic_decode_init(AVCodecContext *avctx)
754. {
755.     SonicContext *s = avctx->priv_data;
         ^
756.     GetBitContext gb;
757.     int i, version;

libavcodec/sonic.c:759:5: 
757.     int i, version;
758. 
759.     s->channels = avctx->channels;
         ^
760.     s->samplerate = avctx->sample_rate;
761. 

libavcodec/sonic.c:760:5: 
758. 
759.     s->channels = avctx->channels;
760.     s->samplerate = avctx->sample_rate;
         ^
761. 
762.     if (!avctx->extradata)

libavcodec/sonic.c:762:10: Taking false branch
760.     s->samplerate = avctx->sample_rate;
761. 
762.     if (!avctx->extradata)
              ^
763.     {
764.         av_log(avctx, AV_LOG_ERROR, "No mandatory headers present\n");

libavcodec/sonic.c:768:5: 
766.     }
767. 
768.     init_get_bits(&gb, avctx->extradata, avctx->extradata_size);
         ^
769. 
770.     version = get_bits(&gb, 2);

libavcodec/bitstream.h:737:1: start of procedure init_get_bits()
  735.  * @param bit_size the size of the buffer in bits
  736.  */
  737. static inline void init_get_bits(GetBitContext *s,
       ^
  738.                    const uint8_t *buffer, int bit_size)
  739. {

libavcodec/bitstream.h:740:5: 
  738.                    const uint8_t *buffer, int bit_size)
  739. {
  740.     int buffer_size= (bit_size+7)>>3;
           ^
  741.     if(buffer_size < 0 || bit_size < 0) {
  742.         buffer_size = bit_size = 0;

libavcodec/bitstream.h:741:8: Taking true branch
  739. {
  740.     int buffer_size= (bit_size+7)>>3;
  741.     if(buffer_size < 0 || bit_size < 0) {
              ^
  742.         buffer_size = bit_size = 0;
  743.         buffer = NULL;

libavcodec/bitstream.h:742:9: 
  740.     int buffer_size= (bit_size+7)>>3;
  741.     if(buffer_size < 0 || bit_size < 0) {
  742.         buffer_size = bit_size = 0;
               ^
  743.         buffer = NULL;
  744.     }

libavcodec/bitstream.h:743:9: 
  741.     if(buffer_size < 0 || bit_size < 0) {
  742.         buffer_size = bit_size = 0;
  743.         buffer = NULL;
               ^
  744.     }
  745. 

libavcodec/bitstream.h:746:5: 
  744.     }
  745. 
  746.     s->buffer= buffer;
           ^
  747.     s->size_in_bits= bit_size;
  748.     s->buffer_end= buffer + buffer_size;

libavcodec/bitstream.h:747:5: 
  745. 
  746.     s->buffer= buffer;
  747.     s->size_in_bits= bit_size;
           ^
  748.     s->buffer_end= buffer + buffer_size;
  749. #ifdef ALT_BITSTREAM_READER

libavcodec/bitstream.h:748:5: 
  746.     s->buffer= buffer;
  747.     s->size_in_bits= bit_size;
  748.     s->buffer_end= buffer + buffer_size;
           ^
  749. #ifdef ALT_BITSTREAM_READER
  750.     s->index=0;

libavcodec/bitstream.h:750:5: 
  748.     s->buffer_end= buffer + buffer_size;
  749. #ifdef ALT_BITSTREAM_READER
  750.     s->index=0;
           ^
  751. #elif defined LIBMPEG2_BITSTREAM_READER
  752.     s->buffer_ptr = (uint8_t*)((intptr_t)buffer&(~1));

libavcodec/bitstream.h:760:1: return from a call to init_get_bits
  758.     skip_bits_long(s, 0);
  759. #endif
  760. }
       ^
  761. 
  762. static inline void align_get_bits(GetBitContext *s)

libavcodec/sonic.c:770:5: 
768.     init_get_bits(&gb, avctx->extradata, avctx->extradata_size);
769. 
770.     version = get_bits(&gb, 2);
         ^
771.     if (version > 1)
772.     {

libavcodec/bitstream.h:634:1: start of procedure get_bits()
  632.  * Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't
  633.  */
  634. static inline unsigned int get_bits(GetBitContext *s, int n){
       ^
  635.     register int tmp;
  636.     OPEN_READER(re, s)

libavcodec/bitstream.h:636:5: 
  634. static inline unsigned int get_bits(GetBitContext *s, int n){
  635.     register int tmp;
  636.     OPEN_READER(re, s)
           ^
  637.     UPDATE_CACHE(re, s)
  638.     tmp= SHOW_UBITS(re, s, n);

libavcodec/bitstream.h:637:5: 
  635.     register int tmp;
  636.     OPEN_READER(re, s)
  637.     UPDATE_CACHE(re, s)
           ^
  638.     tmp= SHOW_UBITS(re, s, n);
  639.     LAST_SKIP_BITS(re, s, n)
