libavcodec/smacker.c:583: error: Null Dereference
  pointer `&gb->buffer` last assigned on line 581 could be null and is dereferenced by call to `get_bits1()` at line 583, column 9.

libavcodec/smacker.c:567:1: start of procedure smka_decode_frame()
565.  * Decode Smacker audio data
566.  */
567. static int smka_decode_frame(AVCodecContext *avctx, void *data, int *data_size, const uint8_t *buf, int buf_size)
     ^
568. {
569.     GetBitContext gb;

libavcodec/smacker.c:572:5: 
570.     HuffContext h[4];
571.     VLC vlc[4];
572.     int16_t *samples = data;
         ^
573.     int val;
574.     int i, res;

libavcodec/smacker.c:577:5: 
575.     int unp_size;
576.     int bits, stereo;
577.     int pred[2] = {0, 0};
         ^
578. 
579.     unp_size = AV_RL32(buf);

libavcodec/smacker.c:579:5: 
577.     int pred[2] = {0, 0};
578. 
579.     unp_size = AV_RL32(buf);
         ^
580. 
581.     init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);

libavcodec/smacker.c:581:5: 
579.     unp_size = AV_RL32(buf);
580. 
581.     init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);
         ^
582. 
583.     if(!get_bits1(&gb)){

libavcodec/bitstream.h:758:1: start of procedure init_get_bits()
  756.  * @param bit_size the size of the buffer in bits
  757.  */
  758. static inline void init_get_bits(GetBitContext *s,
       ^
  759.                    const uint8_t *buffer, int bit_size)
  760. {

libavcodec/bitstream.h:761:5: 
  759.                    const uint8_t *buffer, int bit_size)
  760. {
  761.     int buffer_size= (bit_size+7)>>3;
           ^
  762.     if(buffer_size < 0 || bit_size < 0) {
  763.         buffer_size = bit_size = 0;

libavcodec/bitstream.h:762:8: Taking true branch
  760. {
  761.     int buffer_size= (bit_size+7)>>3;
  762.     if(buffer_size < 0 || bit_size < 0) {
              ^
  763.         buffer_size = bit_size = 0;
  764.         buffer = NULL;

libavcodec/bitstream.h:763:9: 
  761.     int buffer_size= (bit_size+7)>>3;
  762.     if(buffer_size < 0 || bit_size < 0) {
  763.         buffer_size = bit_size = 0;
               ^
  764.         buffer = NULL;
  765.     }

libavcodec/bitstream.h:764:9: 
  762.     if(buffer_size < 0 || bit_size < 0) {
  763.         buffer_size = bit_size = 0;
  764.         buffer = NULL;
               ^
  765.     }
  766. 

libavcodec/bitstream.h:767:5: 
  765.     }
  766. 
  767.     s->buffer= buffer;
           ^
  768.     s->size_in_bits= bit_size;
  769.     s->buffer_end= buffer + buffer_size;

libavcodec/bitstream.h:768:5: 
  766. 
  767.     s->buffer= buffer;
  768.     s->size_in_bits= bit_size;
           ^
  769.     s->buffer_end= buffer + buffer_size;
  770. #ifdef ALT_BITSTREAM_READER

libavcodec/bitstream.h:769:5: 
  767.     s->buffer= buffer;
  768.     s->size_in_bits= bit_size;
  769.     s->buffer_end= buffer + buffer_size;
           ^
  770. #ifdef ALT_BITSTREAM_READER
  771.     s->index=0;

libavcodec/bitstream.h:771:5: 
  769.     s->buffer_end= buffer + buffer_size;
  770. #ifdef ALT_BITSTREAM_READER
  771.     s->index=0;
           ^
  772. #elif defined LIBMPEG2_BITSTREAM_READER
  773.     s->buffer_ptr = (uint8_t*)((intptr_t)buffer&(~1));

libavcodec/bitstream.h:781:1: return from a call to init_get_bits
  779.     skip_bits_long(s, 0);
  780. #endif
  781. }
       ^
  782. 
  783. static inline void align_get_bits(GetBitContext *s)

libavcodec/smacker.c:583:9: 
581.     init_get_bits(&gb, buf + 4, (buf_size - 4) * 8);
582. 
583.     if(!get_bits1(&gb)){
             ^
584.         av_log(avctx, AV_LOG_INFO, "Sound: no data\n");
585.         *data_size = 0;

libavcodec/bitstream.h:686:1: start of procedure get_bits1()
  684. }
  685. 
  686. static inline unsigned int get_bits1(GetBitContext *s){
       ^
  687. #ifdef ALT_BITSTREAM_READER
  688.     int index= s->index;

libavcodec/bitstream.h:688:5: 
  686. static inline unsigned int get_bits1(GetBitContext *s){
  687. #ifdef ALT_BITSTREAM_READER
  688.     int index= s->index;
           ^
  689.     uint8_t result= s->buffer[ index>>3 ];
  690. #ifdef ALT_BITSTREAM_READER_LE

libavcodec/bitstream.h:689:5: 
  687. #ifdef ALT_BITSTREAM_READER
  688.     int index= s->index;
  689.     uint8_t result= s->buffer[ index>>3 ];
           ^
  690. #ifdef ALT_BITSTREAM_READER_LE
  691.     result>>= (index&0x07);
