libavcodec/alsdec.c:1125: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned32 by call to `read_decode_block`.

libavcodec/alsdec.c:1083:28: Assignment
1081.     unsigned int b;
1082.     int ret;
1083.     ALSBlockData bd[2] = { { 0 } };
                                 ^
1084. 
1085.     bd[0].ra_block         = ra_frame;

libavcodec/alsdec.c:1125:20: Call
1123. 
1124.         if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1125.             (ret = read_decode_block(ctx, &bd[1])) < 0)
                         ^
1126.             goto fail;
1127. 

libavcodec/alsdec.c:1006:1: Parameter `bd->block_length`
  1004. /** Read and decode block data successively.
  1005.  */
  1006. static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
        ^
  1007. {
  1008.     int ret;

libavcodec/alsdec.c:1013:12: Call
  1011.         return ret;
  1012. 
  1013.     return decode_block(ctx, bd);
                   ^
  1014. }
  1015. 

libavcodec/alsdec.c:980:1: Parameter `bd->block_length`
    978. /** Decode the block data.
    979.  */
    980. static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
         ^
    981. {
    982.     unsigned int smp;

libavcodec/alsdec.c:987:9: Call
    985.     // read block type flag and read the samples accordingly
    986.     if (*bd->const_block)
    987.         decode_const_block_data(ctx, bd);
                 ^
    988.     else
    989.         ret = decode_var_block_data(ctx, bd); // always return 0

libavcodec/alsdec.c:577:1: <LHS trace>
575. /** Decode the block data for a constant block
576.  */
577. static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
     ^
578. {
579.     int      smp = bd->block_length - 1;

libavcodec/alsdec.c:577:1: Parameter `bd->block_length`
      575. /** Decode the block data for a constant block
      576.  */
      577. static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
           ^
      578. {
      579.     int      smp = bd->block_length - 1;

libavcodec/alsdec.c:579:5: Binary operation: ([0, +oo] - 1):unsigned32 by call to `read_decode_block` 
      577. static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
      578. {
      579.     int      smp = bd->block_length - 1;
               ^
      580.     int32_t  val = *bd->raw_samples;
      581.     int32_t *dst = bd->raw_samples + 1;
