base.Timer.Start("fe", "parse")

	// Limit the number of simultaneously open files.
	sem := make(chan struct{}, runtime.GOMAXPROCS(0)+10)

	noders := make([]*noder, len(filenames))
	for i := range noders {
		p := noder{
			err: make(chan syntax.Error),
		}
		noders[i] = &p
	}

	// Move the entire syntax processing logic into a separate goroutine to avoid blocking on the "sem".
	go func() {

// This file contains the module-mode package loader, as well as some accessory
// functions pertaining to the package import graph.
//
// There are two exported entry points into package loading — LoadPackages and
// ImportFromFiles — both implemented in terms of loadFromRoots, which itself
// manipulates an instance of the loader struct.
//
// Although most of the loading state is maintained in the loader struct,

	// golden functions we use repeatedly
	zero := func(x int64) int64 { return 0 }
	id := func(x int64) int64 { return x }
	or := func(x, y int64) int64 { return x | y }
	and := func(x, y int64) int64 { return x & y }
	y := func(x, y int64) int64 { return y }

	for _, test := range [...]struct {
		name   string
		f      func(int64) int64
		golden func(int64) int64
	}{

	if n.loader != nil {
		assert(n.underlying == nil)
		assert(n.TypeArgs().Len() == 0) // instances are created by instantiation, in which case n.loader is nil

		tparams, underlying, methods := n.loader(n)

		n.tparams = bindTParams(tparams)
		n.underlying = underlying
		n.fromRHS = underlying // for cycle detection
		n.methods = methods
		n.loader = nil
	}

	n.setState(complete)

		walk(m)
		haveBase[path] = true
	}
	// Now the reverse postorder to bring in anything else.
	for i := len(postorder) - 1; i >= 0; i-- {
		m := postorder[i]
		if max[m.Path] != m.Version {
			// Older version.
			continue
		}
		if !have[m] {
			min = append(min, m)
			walk(m)
		}
	}
	sort.Slice(min, func(i, j int) bool {
		return min[i].Path < min[j].Path
	})
	return min, nil
}

	"os"
	"sort"

	"cmd/go/internal/gover"
	"cmd/go/internal/modfetch"
	"cmd/go/internal/modfetch/codehost"

	"golang.org/x/mod/module"
)

// cmpVersion implements the comparison for versions in the module loader.
//
// It is consistent with gover.ModCompare except that as a special case,
// the version "" is considered higher than all other versions.
// The main module (also known as the target) has no version and must be chosen

	if gover.Compare(modload.MainModules.GoVersion(), "1.22") >= 0 {
		embedPatterns = bp.EmbedPatterns
	} else {
		// Maintain the behavior of https://github.com/golang/go/issues/63473
		// so that we continue to agree with older versions of the go command
		// about the contents of vendor directories in existing modules
		embedPatterns = str.StringList(bp.EmbedPatterns, bp.TestEmbedPatterns, bp.XTestEmbedPatterns)
	}

	dir, _ := cache.DefaultDir()
	if strings.HasPrefix(src, dir) {
		return sh.CopyFile(dst, src, perm, force)
	}

	// On Windows, always copy the file, so that we respect the NTFS
	// permissions of the parent folder. https://golang.org/issue/22343.
	// What matters here is not cfg.Goos (the system we are building
	// for) but runtime.GOOS (the system we are building on).
	if runtime.GOOS == "windows" {

//
// We set the mtime on a cache file on each use, but at most one per mtimeInterval (1 hour),
// to avoid causing many unnecessary inode updates. The mtimes therefore
// roughly reflect "time of last use" but may in fact be older by at most an hour.
//
// We scan the cache for entries to delete at most once per trimInterval (1 day).
//
// When we do scan the cache, we delete entries that have not been used for

	//
	// Reference:
	//	http://pubs.opengroup.org/onlinepubs/009695399/utilities/pax.html
	FormatPAX

	// FormatGNU represents the GNU header format.
	//
	// The GNU header format is older than the USTAR and PAX standards and
	// is not compatible with them. The GNU format supports
	// arbitrary file sizes, filenames of arbitrary encoding and length,
	// sparse files, and other features.
	//