PVS-Studio warning V547 for DeSmuME

static bool _FAT_check_position_for_next_cluster(....,
 size_t remain, ....)
{
  ...
  if ((remain < 0) ||
      (position->sector > partition->sectorsPerCluster)) {
    // invalid arguments - internal error
    r->_errno = EINVAL;
    goto err;
  }
  ...
}

This suspicious code was found in DeSmuME project by PVS-Studio static code analyzer.
Warning message is:
V547 Expression 'remain < 0' is always false. Unsigned type value is never < 0. DeSmuME_VS2005 fatfile.cpp 527

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