libavcodec/aacdec.c:490: error: Null Dereference
  pointer `&gb->buffer` last assigned on line 473 could be null and is dereferenced by call to `decode_ga_specific_config()` at line 490, column 13.

libavcodec/aacdec.c:460:1: start of procedure decode_audio_specific_config()
458.  * @return  Returns error status or number of consumed bits. <0 - error
459.  */
460. static int decode_audio_specific_config(AACContext *ac,
     ^
461.                                         AVCodecContext *avctx,
462.                                         MPEG4AudioConfig *m4ac,

libavcodec/aacdec.c:469:10: 
467. 
468.     av_dlog(avctx, "extradata size %d\n", avctx->extradata_size);
469.     for (i = 0; i < avctx->extradata_size; i++)
              ^
470.          av_dlog(avctx, "%02x ", avctx->extradata[i]);
471.     av_dlog(avctx, "\n");

libavcodec/aacdec.c:469:17: Loop condition is false. Leaving loop
467. 
468.     av_dlog(avctx, "extradata size %d\n", avctx->extradata_size);
469.     for (i = 0; i < avctx->extradata_size; i++)
                     ^
470.          av_dlog(avctx, "%02x ", avctx->extradata[i]);
471.     av_dlog(avctx, "\n");

libavcodec/aacdec.c:473:5: 
471.     av_dlog(avctx, "\n");
472. 
473.     init_get_bits(&gb, data, data_size * 8);
         ^
474. 
475.     if ((i = avpriv_mpeg4audio_get_config(m4ac, data, data_size)) < 0)

libavcodec/get_bits.h:383:1: start of procedure init_get_bits()
  381.  * responsible for checking for the buffer end yourself (take advantage of the padding)!
  382.  */
  383. static inline void init_get_bits(GetBitContext *s,
       ^
  384.                    const uint8_t *buffer, int bit_size)
  385. {

libavcodec/get_bits.h:386:5: 
  384.                    const uint8_t *buffer, int bit_size)
  385. {
  386.     int buffer_size = (bit_size+7)>>3;
           ^
  387.     if (buffer_size < 0 || bit_size < 0) {
  388.         buffer_size = bit_size = 0;

libavcodec/get_bits.h:387:9: Taking true branch
  385. {
  386.     int buffer_size = (bit_size+7)>>3;
  387.     if (buffer_size < 0 || bit_size < 0) {
               ^
  388.         buffer_size = bit_size = 0;
  389.         buffer = NULL;

libavcodec/get_bits.h:388:9: 
  386.     int buffer_size = (bit_size+7)>>3;
  387.     if (buffer_size < 0 || bit_size < 0) {
  388.         buffer_size = bit_size = 0;
               ^
  389.         buffer = NULL;
  390.     }

libavcodec/get_bits.h:389:9: 
  387.     if (buffer_size < 0 || bit_size < 0) {
  388.         buffer_size = bit_size = 0;
  389.         buffer = NULL;
               ^
  390.     }
  391. 

libavcodec/get_bits.h:392:5: 
  390.     }
  391. 
  392.     s->buffer       = buffer;
           ^
  393.     s->size_in_bits = bit_size;
  394.     s->buffer_end   = buffer + buffer_size;

libavcodec/get_bits.h:393:5: 
  391. 
  392.     s->buffer       = buffer;
  393.     s->size_in_bits = bit_size;
           ^
  394.     s->buffer_end   = buffer + buffer_size;
  395. #ifdef ALT_BITSTREAM_READER

libavcodec/get_bits.h:394:5: 
  392.     s->buffer       = buffer;
  393.     s->size_in_bits = bit_size;
  394.     s->buffer_end   = buffer + buffer_size;
           ^
  395. #ifdef ALT_BITSTREAM_READER
  396.     s->index        = 0;

libavcodec/get_bits.h:396:5: 
  394.     s->buffer_end   = buffer + buffer_size;
  395. #ifdef ALT_BITSTREAM_READER
  396.     s->index        = 0;
           ^
  397. #elif defined A32_BITSTREAM_READER
  398.     s->buffer_ptr   = (uint32_t*)((intptr_t)buffer & ~3);

libavcodec/get_bits.h:402:1: return from a call to init_get_bits
  400.     skip_bits_long(s, 0);
  401. #endif
  402. }
       ^
  403. 
  404. static inline void align_get_bits(GetBitContext *s)

libavcodec/aacdec.c:475:9: Taking false branch
473.     init_get_bits(&gb, data, data_size * 8);
474. 
475.     if ((i = avpriv_mpeg4audio_get_config(m4ac, data, data_size)) < 0)
             ^
476.         return -1;
477.     if (m4ac->sampling_index > 12) {

libavcodec/aacdec.c:477:9: Taking false branch
475.     if ((i = avpriv_mpeg4audio_get_config(m4ac, data, data_size)) < 0)
476.         return -1;
477.     if (m4ac->sampling_index > 12) {
             ^
478.         av_log(avctx, AV_LOG_ERROR, "invalid sampling rate index %d\n", m4ac->sampling_index);
479.         return -1;

libavcodec/aacdec.c:481:9: Taking true branch
479.         return -1;
480.     }
481.     if (m4ac->sbr == 1 && m4ac->ps == -1)
             ^
482.         m4ac->ps = 1;
483. 

libavcodec/aacdec.c:481:27: Taking false branch
479.         return -1;
480.     }
481.     if (m4ac->sbr == 1 && m4ac->ps == -1)
                               ^
482.         m4ac->ps = 1;
483. 

libavcodec/aacdec.c:484:5: 
482.         m4ac->ps = 1;
483. 
484.     skip_bits_long(&gb, i);
         ^
485. 
486.     switch (m4ac->object_type) {

libavcodec/get_bits.h:173:1: start of procedure skip_bits_long()
  171. }
  172. 
  173. static inline void skip_bits_long(GetBitContext *s, int n){
       ^
  174.     s->index += n;
  175. }

libavcodec/get_bits.h:174:5: 
  172. 
  173. static inline void skip_bits_long(GetBitContext *s, int n){
  174.     s->index += n;
           ^
  175. }
  176. 

libavcodec/get_bits.h:175:1: return from a call to skip_bits_long
  173. static inline void skip_bits_long(GetBitContext *s, int n){
  174.     s->index += n;
  175. }
       ^
  176. 
  177. #elif defined A32_BITSTREAM_READER

libavcodec/aacdec.c:486:5: 
484.     skip_bits_long(&gb, i);
485. 
486.     switch (m4ac->object_type) {
         ^
487.     case AOT_AAC_MAIN:
488.     case AOT_AAC_LC:

libavcodec/aacdec.c:487:5: Switch condition is true. Entering switch case
485. 
486.     switch (m4ac->object_type) {
487.     case AOT_AAC_MAIN:
         ^
488.     case AOT_AAC_LC:
489.     case AOT_AAC_LTP:

libavcodec/aacdec.c:490:13: 
488.     case AOT_AAC_LC:
489.     case AOT_AAC_LTP:
490.         if (decode_ga_specific_config(ac, avctx, &gb, m4ac, m4ac->chan_config))
                 ^
491.             return -1;
492.         break;
