libavcodec/svq1dec.c:566: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned32 by call to `bitstream_skip`.

libavcodec/svq1dec.c:565:9: Call
563. 
564.         bitstream_skip(bc, 2);
565.         bitstream_skip(bc, 2);
             ^
566.         bitstream_skip(bc, 1);
567. 

libavcodec/bitstream.h:247:9: Assignment
  245.         n -= bc->bits_left;
  246.         bc->bits      = 0;
  247.         bc->bits_left = 0;
               ^
  248. 
  249.         if (n >= 64) {

libavcodec/bitstream.h:255:9: Call
  253.             bc->ptr += skip;
  254.         }
  255.         refill_64(bc);
               ^
  256.         if (n)
  257.             skip_remaining(bc, n);

libavcodec/bitstream.h:45:1: Parameter `bc->bits_left`
    43. } BitstreamContext;
    44. 
    45. static inline void refill_64(BitstreamContext *bc)
        ^
    46. {
    47.     if (bc->ptr >= bc->buffer_end)

libavcodec/svq1dec.c:566:9: Call
564.         bitstream_skip(bc, 2);
565.         bitstream_skip(bc, 2);
566.         bitstream_skip(bc, 1);
             ^
567. 
568.         /* load frame size */

libavcodec/bitstream.h:240:1: Parameter `n`
  238. 
  239. /* Skip n bits in the buffer. */
  240. static inline void bitstream_skip(BitstreamContext *bc, unsigned n)
       ^
  241. {
  242.     if (n < bc->bits_left)

libavcodec/bitstream.h:243:9: Call
  241. {
  242.     if (n < bc->bits_left)
  243.         skip_remaining(bc, n);
               ^
  244.     else {
  245.         n -= bc->bits_left;

libavcodec/bitstream.h:229:1: <LHS trace>
227. }
228. 
229. static inline void skip_remaining(BitstreamContext *bc, unsigned n)
     ^
230. {
231. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:229:1: Parameter `bc->bits_left`
    227. }
    228. 
    229. static inline void skip_remaining(BitstreamContext *bc, unsigned n)
         ^
    230. {
    231. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:229:1: <RHS trace>
227. }
228. 
229. static inline void skip_remaining(BitstreamContext *bc, unsigned n)
     ^
230. {
231. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:229:1: Parameter `n`
    227. }
    228. 
    229. static inline void skip_remaining(BitstreamContext *bc, unsigned n)
         ^
    230. {
    231. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:236:5: Binary operation: ([0, +oo] - 1):unsigned32 by call to `bitstream_skip` 
    234.     bc->bits <<= n;
    235. #endif
    236.     bc->bits_left -= n;
             ^
    237. }
    238. 

static inline void skip_remaining(BitstreamContext *bc, unsigned n)
{
#ifdef BITSTREAM_READER_LE
    bc->bits >>= n;
#else
    bc->bits <<= n;
#endif
    bc->bits_left -= n;
}
['static int svq1_decode_frame_header(AVCodecContext *avctx, AVFrame *frame)\n{\n    SVQ1Context *s = avctx->priv_data;\n    BitstreamContext *bc = &s->bc;\n    int frame_size_code;\n    bitstream_skip(bc, 8);\n    s->nonref = 0;\n    switch (bitstream_read(bc, 2)) {\n    case 0:\n        frame->pict_type = AV_PICTURE_TYPE_I;\n        break;\n    case 2:\n        s->nonref = 1;\n    case 1:\n        frame->pict_type = AV_PICTURE_TYPE_P;\n        break;\n    default:\n        av_log(avctx, AV_LOG_ERROR, "Invalid frame type.\\n");\n        return AVERROR_INVALIDDATA;\n    }\n    if (frame->pict_type == AV_PICTURE_TYPE_I) {\n        if (s->frame_code == 0x50 || s->frame_code == 0x60) {\n            int csum = bitstream_read(bc, 16);\n            csum = ff_svq1_packet_checksum(bc->buffer, bc->size_in_bits >> 3,\n                                           csum);\n            ff_dlog(avctx, "%s checksum (%02x) for packet data\\n",\n                    (csum == 0) ? "correct" : "incorrect", csum);\n        }\n        if ((s->frame_code ^ 0x10) >= 0x50) {\n            uint8_t msg[256];\n            svq1_parse_string(bc, msg);\n            av_log(avctx, AV_LOG_INFO,\n                   "embedded message: \\"%s\\"\\n", (char *)msg);\n        }\n        bitstream_skip(bc, 2);\n        bitstream_skip(bc, 2);\n        bitstream_skip(bc, 1);\n        frame_size_code = bitstream_read(bc, 3);\n        if (frame_size_code == 7) {\n            s->width  = bitstream_read(bc, 12);\n            s->height = bitstream_read(bc, 12);\n            if (!s->width || !s->height)\n                return AVERROR_INVALIDDATA;\n        } else {\n            s->width  = ff_svq1_frame_size_table[frame_size_code][0];\n            s->height = ff_svq1_frame_size_table[frame_size_code][1];\n        }\n    }\n    if (bitstream_read_bit(bc) == 1) {\n        bitstream_skip(bc, 1);\n        bitstream_skip(bc, 1);\n        if (bitstream_read(bc, 2) != 0)\n            return AVERROR_INVALIDDATA;\n    }\n    if (bitstream_read_bit(bc) == 1) {\n        bitstream_skip(bc, 1);\n        bitstream_skip(bc, 4);\n        bitstream_skip(bc, 1);\n        bitstream_skip(bc, 2);\n        while (bitstream_read_bit(bc) == 1)\n            bitstream_skip(bc, 8);\n    }\n    return 0;\n}', 'static inline void bitstream_skip(BitstreamContext *bc, unsigned n)\n{\n    if (n < bc->bits_left)\n        skip_remaining(bc, n);\n    else {\n        n -= bc->bits_left;\n        bc->bits      = 0;\n        bc->bits_left = 0;\n        if (n >= 64) {\n            unsigned skip = n / 8;\n            n -= skip * 8;\n            bc->ptr += skip;\n        }\n        refill_64(bc);\n        if (n)\n            skip_remaining(bc, n);\n    }\n}', 'static inline void refill_64(BitstreamContext *bc)\n{\n    if (bc->ptr >= bc->buffer_end)\n        return;\n#ifdef BITSTREAM_READER_LE\n    bc->bits       = AV_RL64(bc->ptr);\n#else\n    bc->bits       = AV_RB64(bc->ptr);\n#endif\n    bc->ptr       += 8;\n    bc->bits_left  = 64;\n}', 'static inline void skip_remaining(BitstreamContext *bc, unsigned n)\n{\n#ifdef BITSTREAM_READER_LE\n    bc->bits >>= n;\n#else\n    bc->bits <<= n;\n#endif\n    bc->bits_left -= n;\n}']