libavcodec/webp.c:696: error: Integer Overflow L2
  ([1, +oo] - [1, 18]):unsigned32 by call to `bitstream_read`.

libavcodec/webp.c:639:17: Call
637. 
638.             if (bitstream_read_bit(&s->bc)) {
639.                 read_huffman_code_simple(s, &hg[j]);
                     ^
640.             } else {
641.                 ret = read_huffman_code_normal(s, &hg[j], alphabet_size);

libavcodec/webp.c:334:1: Parameter `hc->simple_symbols[*]`
  332. }
  333. 
  334. static void read_huffman_code_simple(WebPContext *s, HuffReader *hc)
       ^
  335. {
  336.     hc->nb_symbols = bitstream_read_bit(&s->bc) + 1;

libavcodec/webp.c:685:27: Call
683.                 length = offset + bitstream_read(&s->bc, extra_bits) + 1;
684.             }
685.             prefix_code = huff_reader_get_symbol(&hg[HUFF_IDX_DIST], &s->bc);
                               ^
686.             if (prefix_code > 39) {
687.                 av_log(s->avctx, AV_LOG_ERROR,

libavcodec/webp.c:261:1: Parameter `r->simple_symbols[*]`
  259. }
  260. 
  261. static int huff_reader_get_symbol(HuffReader *r, BitstreamContext *bc)
       ^
  262. {
  263.     if (r->simple) {

libavcodec/webp.c:265:13: Assignment
  263.     if (r->simple) {
  264.         if (r->nb_symbols == 1)
  265.             return r->simple_symbols[0];
                   ^
  266.         else
  267.             return r->simple_symbols[bitstream_read_bit(bc)];

libavcodec/webp.c:685:13: Assignment
683.                 length = offset + bitstream_read(&s->bc, extra_bits) + 1;
684.             }
685.             prefix_code = huff_reader_get_symbol(&hg[HUFF_IDX_DIST], &s->bc);
                 ^
686.             if (prefix_code > 39) {
687.                 av_log(s->avctx, AV_LOG_ERROR,

libavcodec/webp.c:694:17: Assignment
692.                 distance = prefix_code + 1;
693.             } else {
694.                 int extra_bits = prefix_code - 2 >> 1;
                     ^
695.                 int offset     = 2 + (prefix_code & 1) << extra_bits;
696.                 distance = offset + bitstream_read(&s->bc, extra_bits) + 1;

libavcodec/webp.c:696:37: Call
694.                 int extra_bits = prefix_code - 2 >> 1;
695.                 int offset     = 2 + (prefix_code & 1) << extra_bits;
696.                 distance = offset + bitstream_read(&s->bc, extra_bits) + 1;
                                         ^
697.             }
698. 

libavcodec/bitstream.h:183:1: Parameter `n`
  181. 
  182. /* Return n bits from the buffer. n has to be in the 0-32 range. */
  183. static inline uint32_t bitstream_read(BitstreamContext *bc, unsigned n)
       ^
  184. {
  185.     if (!n)

libavcodec/bitstream.h:194:12: Call
  192.     }
  193. 
  194.     return get_val(bc, n);
                  ^
  195. }
  196. 

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: ([1, +oo] - [1, 18]):unsigned32 by call to `bitstream_read` 
    137.     bc->bits <<= n;
    138. #endif
    139.     bc->bits_left -= n;
             ^
    140. 
    141.     return ret;
