On Windows, the mode bits reported by [Lstat] and [Stat] for
reparse points changed. Mount points no longer have [ModeSymlink] set,
and reparse points that are not symlinks, Unix sockets, or dedup files
now always have [ModeIrregular] set.
This behavior is controlled by the `winsymlink` setting.
For Go 1.23, it defaults to `winsymlink=1`.

	ModeSetgid     = fs.ModeSetgid     // g: setgid
	ModeCharDevice = fs.ModeCharDevice // c: Unix character device, when ModeDevice is set
	ModeSticky     = fs.ModeSticky     // t: sticky
	ModeIrregular  = fs.ModeIrregular  // ?: non-regular file; nothing else is known about this file

	// Mask for the type bits. For regular files, none will be set.
	ModeType = fs.ModeType

	ModePerm = fs.ModePerm // Unix permission bits, 0o777

			//
			// Go programs may use ModeIrregular to filter out unusual files (such as
			// raw device files on Linux, POSIX FIFO special files, and so on), so
			// to avoid files changing unpredictably from regular to irregular we will
			// consider DEDUP files to be close enough to regular to treat as such.
		default:
			m |= ModeIrregular
		}
	}
	return
}

	case syscall.S_IFLNK:
		fs.mode |= ModeSymlink
	case syscall.S_IFREG:
		// nothing to do
	case syscall.S_IFSOCK:
		fs.mode |= ModeSocket
	case _S_IFNAM, _S_IFDOOR, _S_IFPORT:
		fs.mode |= ModeIrregular
	}
	if fs.sys.Mode&syscall.S_ISGID != 0 {
		fs.mode |= ModeSetgid
	}
	if fs.sys.Mode&syscall.S_ISUID != 0 {
		fs.mode |= ModeSetuid
	}
	if fs.sys.Mode&syscall.S_ISVTX != 0 {
		fs.mode |= ModeSticky
	}

			isDir:   true,
		},
		"drwxr-xr-x 0 1970-01-01 12:00:00 home/gopher/",
		"d home/gopher/",
	},
	{
		formatTest{
			name:    "big",
			size:    0x7fffffffffffffff,
			mode:    ModeIrregular | 0o644,
			modTime: time.Date(1970, time.January, 1, 12, 0, 0, 0, time.UTC),
			isDir:   false,
		},
		"?rw-r--r-- 9223372036854775807 1970-01-01 12:00:00 big",
		"? big",
	},
	{
		formatTest{

	ModeSticky                                     // t: sticky
	ModeIrregular                                  // ?: non-regular file; nothing else is known about this file

	// Mask for the type bits. For regular files, none will be set.
	ModeType = ModeDir | ModeSymlink | ModeNamedPipe | ModeSocket | ModeDevice | ModeCharDevice | ModeIrregular

	ModePerm FileMode = 0777 // Unix permission bits
)

As of Go 1.23 (`winsymlink=1`), mount points no longer have [`os.ModeSymlink`](/pkg/os#ModeSymlink)
set, and reparse points that are not symlinks, Unix sockets, or dedup files now
always have [`os.ModeIrregular`](/pkg/os#ModeIrregular) set. As a result of these changes,
[`filepath.EvalSymlinks`](/pkg/path/filepath#EvalSymlinks) no longer evaluates
mount points, which was a source of many inconsistencies and bugs.

// for the fileInfo methods other than Name, set to the file's name, and Mode
// set to ModeIrregular.
type missingFile string

func (f missingFile) Name() string       { return string(f) }
func (f missingFile) Size() int64        { return 0 }
func (f missingFile) Mode() fs.FileMode  { return fs.ModeIrregular }
func (f missingFile) ModTime() time.Time { return time.Unix(0, 0) }

			continue
		}
		var wantType fs.FileMode
		if test.isMountPoint && winsymlink.Value() != "0" {
			// Mount points are reparse points, and we no longer treat them as symlinks.
			wantType = fs.ModeIrregular
		} else {
			// This is either a real symlink, or a mount point treated as a symlink.
			wantType = fs.ModeSymlink
		}
		if tp := fi2.Mode().Type(); tp != wantType {

pkg os, const ModeAppend FileMode
pkg os, const ModeCharDevice FileMode
pkg os, const ModeDevice FileMode
pkg os, const ModeDir FileMode
pkg os, const ModeExclusive FileMode
pkg os, const ModeIrregular FileMode
pkg os, const ModeNamedPipe FileMode
pkg os, const ModePerm FileMode
pkg os, const ModeSetgid FileMode
pkg os, const ModeSetuid FileMode
pkg os, const ModeSocket FileMode
pkg os, const ModeSticky FileMode