libavcodec/smacker.c:307: error: Integer Overflow L2
  ([0, 64] - 1):unsigned32 by call to `bitstream_read_bit`.

libavcodec/smacker.c:305:5: Call
303.     type_size = AV_RL32(smk->avctx->extradata + 12);
304. 
305.     bitstream_init(&bc, smk->avctx->extradata + 16, (smk->avctx->extradata_size - 16) * 8);
         ^
306. 
307.     if (!bitstream_read_bit(&bc)) {

libavcodec/bitstream.h:85:9: Assignment
  83.         bc->buffer    =
  84.         bc->ptr       = NULL;
  85.         bc->bits_left = 0;
              ^
  86.         return AVERROR_INVALIDDATA;
  87.     }

libavcodec/smacker.c:307:10: Call
305.     bitstream_init(&bc, smk->avctx->extradata + 16, (smk->avctx->extradata_size - 16) * 8);
306. 
307.     if (!bitstream_read_bit(&bc)) {
              ^
308.         av_log(smk->avctx, AV_LOG_INFO, "Skipping MMAP tree\n");
309.         smk->mmap_tbl = av_malloc(sizeof(int) * 2);

libavcodec/bitstream.h:145:1: Parameter `bc->bits_left`
  143. 
  144. /* Return one bit from the buffer. */
  145. static inline unsigned bitstream_read_bit(BitstreamContext *bc)
       ^
  146. {
  147.     if (!bc->bits_left)

libavcodec/bitstream.h:150:12: Call
  148.         refill_64(bc);
  149. 
  150.     return get_val(bc, 1);
                  ^
  151. }
  152. 

libavcodec/bitstream.h:130:1: <LHS trace>
128. }
129. 
130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
     ^
131. {
132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: Parameter `bc->bits_left`
    128. }
    129. 
    130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
         ^
    131. {
    132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: <RHS trace>
128. }
129. 
130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
     ^
131. {
132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: Parameter `n`
    128. }
    129. 
    130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
         ^
    131. {
    132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:139:5: Binary operation: ([0, 64] - 1):unsigned32 by call to `bitstream_read_bit` 
    137.     bc->bits <<= n;
    138. #endif
    139.     bc->bits_left -= n;
             ^
    140. 
    141.     return ret;
