libavcodec/aacdec.c:484: error: Null Dereference
  pointer `&gb->buffer` last assigned on line 467 could be null and is dereferenced by call to `decode_ga_specific_config()` at line 484, column 13.

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

libavcodec/aacdec.c:467:5: 
465.     int i;
466. 
467.     init_get_bits(&gb, data, data_size * 8);
         ^
468. 
469.     if ((i = ff_mpeg4audio_get_config(m4ac, data, data_size)) < 0)

libavcodec/get_bits.h:391:1: start of procedure init_get_bits()
  389.  * responsible for checking for the buffer end yourself (take advantage of the padding)!
  390.  */
  391. static inline void init_get_bits(GetBitContext *s,
       ^
  392.                    const uint8_t *buffer, int bit_size)
  393. {

libavcodec/get_bits.h:394:5: 
  392.                    const uint8_t *buffer, int bit_size)
  393. {
  394.     int buffer_size = (bit_size+7)>>3;
           ^
  395.     if (buffer_size < 0 || bit_size < 0) {
  396.         buffer_size = bit_size = 0;

libavcodec/get_bits.h:395:9: Taking true branch
  393. {
  394.     int buffer_size = (bit_size+7)>>3;
  395.     if (buffer_size < 0 || bit_size < 0) {
               ^
  396.         buffer_size = bit_size = 0;
  397.         buffer = NULL;

libavcodec/get_bits.h:396:9: 
  394.     int buffer_size = (bit_size+7)>>3;
  395.     if (buffer_size < 0 || bit_size < 0) {
  396.         buffer_size = bit_size = 0;
               ^
  397.         buffer = NULL;
  398.     }

libavcodec/get_bits.h:397:9: 
  395.     if (buffer_size < 0 || bit_size < 0) {
  396.         buffer_size = bit_size = 0;
  397.         buffer = NULL;
               ^
  398.     }
  399. 

libavcodec/get_bits.h:400:5: 
  398.     }
  399. 
  400.     s->buffer       = buffer;
           ^
  401.     s->size_in_bits = bit_size;
  402.     s->buffer_end   = buffer + buffer_size;

libavcodec/get_bits.h:401:5: 
  399. 
  400.     s->buffer       = buffer;
  401.     s->size_in_bits = bit_size;
           ^
  402.     s->buffer_end   = buffer + buffer_size;
  403. #ifdef ALT_BITSTREAM_READER

libavcodec/get_bits.h:402:5: 
  400.     s->buffer       = buffer;
  401.     s->size_in_bits = bit_size;
  402.     s->buffer_end   = buffer + buffer_size;
           ^
  403. #ifdef ALT_BITSTREAM_READER
  404.     s->index        = 0;

libavcodec/get_bits.h:404:5: 
  402.     s->buffer_end   = buffer + buffer_size;
  403. #ifdef ALT_BITSTREAM_READER
  404.     s->index        = 0;
           ^
  405. #elif defined A32_BITSTREAM_READER
  406.     s->buffer_ptr   = (uint32_t*)((intptr_t)buffer & ~3);

libavcodec/get_bits.h:410:1: return from a call to init_get_bits
  408.     skip_bits_long(s, 0);
  409. #endif
  410. }
       ^
  411. 
  412. static inline void align_get_bits(GetBitContext *s)

libavcodec/aacdec.c:469:9: Taking false branch
467.     init_get_bits(&gb, data, data_size * 8);
468. 
469.     if ((i = ff_mpeg4audio_get_config(m4ac, data, data_size)) < 0)
             ^
470.         return -1;
471.     if (m4ac->sampling_index > 12) {

libavcodec/aacdec.c:471:9: Taking false branch
469.     if ((i = ff_mpeg4audio_get_config(m4ac, data, data_size)) < 0)
470.         return -1;
471.     if (m4ac->sampling_index > 12) {
             ^
472.         av_log(avctx, AV_LOG_ERROR, "invalid sampling rate index %d\n", m4ac->sampling_index);
473.         return -1;

libavcodec/aacdec.c:475:9: Taking true branch
473.         return -1;
474.     }
475.     if (m4ac->sbr == 1 && m4ac->ps == -1)
             ^
476.         m4ac->ps = 1;
477. 

libavcodec/aacdec.c:475:27: Taking false branch
473.         return -1;
474.     }
475.     if (m4ac->sbr == 1 && m4ac->ps == -1)
                               ^
476.         m4ac->ps = 1;
477. 

libavcodec/aacdec.c:478:5: 
476.         m4ac->ps = 1;
477. 
478.     skip_bits_long(&gb, i);
         ^
479. 
480.     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:480:5: 
478.     skip_bits_long(&gb, i);
479. 
480.     switch (m4ac->object_type) {
         ^
481.     case AOT_AAC_MAIN:
482.     case AOT_AAC_LC:

libavcodec/aacdec.c:481:5: Switch condition is true. Entering switch case
479. 
480.     switch (m4ac->object_type) {
481.     case AOT_AAC_MAIN:
         ^
482.     case AOT_AAC_LC:
483.     case AOT_AAC_LTP:

libavcodec/aacdec.c:484:13: 
482.     case AOT_AAC_LC:
483.     case AOT_AAC_LTP:
484.         if (decode_ga_specific_config(ac, avctx, &gb, m4ac, m4ac->chan_config))
                 ^
485.             return -1;
486.         break;

static int decode_audio_specific_config(AACContext *ac,
                                        AVCodecContext *avctx,
                                        MPEG4AudioConfig *m4ac,
                                        const uint8_t *data, int data_size)
{
    GetBitContext gb;
    int i;
    init_get_bits(&gb, data, data_size * 8);
    if ((i = ff_mpeg4audio_get_config(m4ac, data, data_size)) < 0)
        return -1;
    if (m4ac->sampling_index > 12) {
        av_log(avctx, AV_LOG_ERROR, "invalid sampling rate index %d\n", m4ac->sampling_index);
        return -1;
    }
    if (m4ac->sbr == 1 && m4ac->ps == -1)
        m4ac->ps = 1;
    skip_bits_long(&gb, i);
    switch (m4ac->object_type) {
    case AOT_AAC_MAIN:
    case AOT_AAC_LC:
    case AOT_AAC_LTP:
        if (decode_ga_specific_config(ac, avctx, &gb, m4ac, m4ac->chan_config))
            return -1;
        break;
    default:
        av_log(avctx, AV_LOG_ERROR, "Audio object type %s%d is not supported.\n",
               m4ac->sbr == 1? "SBR+" : "", m4ac->object_type);
        return -1;
    }
    return get_bits_count(&gb);
}
['static int decode_audio_specific_config(AACContext *ac,\n                                        AVCodecContext *avctx,\n                                        MPEG4AudioConfig *m4ac,\n                                        const uint8_t *data, int data_size)\n{\n    GetBitContext gb;\n    int i;\n    init_get_bits(&gb, data, data_size * 8);\n    if ((i = ff_mpeg4audio_get_config(m4ac, data, data_size)) < 0)\n        return -1;\n    if (m4ac->sampling_index > 12) {\n        av_log(avctx, AV_LOG_ERROR, "invalid sampling rate index %d\\n", m4ac->sampling_index);\n        return -1;\n    }\n    if (m4ac->sbr == 1 && m4ac->ps == -1)\n        m4ac->ps = 1;\n    skip_bits_long(&gb, i);\n    switch (m4ac->object_type) {\n    case AOT_AAC_MAIN:\n    case AOT_AAC_LC:\n    case AOT_AAC_LTP:\n        if (decode_ga_specific_config(ac, avctx, &gb, m4ac, m4ac->chan_config))\n            return -1;\n        break;\n    default:\n        av_log(avctx, AV_LOG_ERROR, "Audio object type %s%d is not supported.\\n",\n               m4ac->sbr == 1? "SBR+" : "", m4ac->object_type);\n        return -1;\n    }\n    return get_bits_count(&gb);\n}', 'static inline void init_get_bits(GetBitContext *s,\n                   const uint8_t *buffer, int bit_size)\n{\n    int buffer_size = (bit_size+7)>>3;\n    if (buffer_size < 0 || bit_size < 0) {\n        buffer_size = bit_size = 0;\n        buffer = NULL;\n    }\n    s->buffer       = buffer;\n    s->size_in_bits = bit_size;\n    s->buffer_end   = buffer + buffer_size;\n#ifdef ALT_BITSTREAM_READER\n    s->index        = 0;\n#elif defined A32_BITSTREAM_READER\n    s->buffer_ptr   = (uint32_t*)((intptr_t)buffer & ~3);\n    s->bit_count    = 32 +     8*((intptr_t)buffer &  3);\n    skip_bits_long(s, 0);\n#endif\n}', 'static inline void skip_bits_long(GetBitContext *s, int n){\n    s->index += n;\n}']