TESTGO_GOROOT=<GOROOT used to build cmd/go, for use in tests that may change GOROOT>
	HOME=/no-home
	PATH=<actual PATH>
	TMPDIR=$WORK/tmp
	GODEBUG=<actual GODEBUG>
	devnull=<value of os.DevNull>
	goversion=<current Go version; for example, 1.12>

On Plan 9, the variables $path and $home are set instead of $PATH and $HOME.
On Windows, the variables $USERPROFILE and $TMP are set instead of
$HOME and $TMPDIR.

		opt(&conf)
	}

	// apply flag setting (overrides custom configuration)
	var goexperiment, gotypesalias string
	flags := flag.NewFlagSet("", flag.PanicOnError)
	flags.StringVar(&conf.GoVersion, "lang", "", "")
	flags.StringVar(&goexperiment, "goexperiment", "", "")
	flags.BoolVar(&conf.FakeImportC, "fakeImportC", false, "")
	flags.StringVar(&gotypesalias, "gotypesalias", "", "")

func Read(r io.ReaderAt) (*BuildInfo, error) {
	vers, mod, err := readRawBuildInfo(r)
	if err != nil {
		return nil, err
	}
	bi, err := debug.ParseBuildInfo(mod)
	if err != nil {
		return nil, err
	}
	bi.GoVersion = vers
	return bi, nil
}

type exe interface {
	// ReadData reads and returns up to size bytes starting at virtual address addr.
	ReadData(addr, size uint64) ([]byte, error)

	tg.grepStdout("-ffaster", "CC arguments not found")

	tg.run("env", "GOVERSION")
	envVersion := strings.TrimSpace(tg.stdout.String())

	tg.run("version")
	cmdVersion := strings.TrimSpace(tg.stdout.String())

	// If 'go version' is "go version <version> <goos>/<goarch>", then
	// 'go env GOVERSION' is just "<version>".
	if cmdVersion == envVersion || !strings.Contains(cmdVersion, envVersion) {

		opt(&conf)
	}

	// apply flag setting (overrides custom configuration)
	var goexperiment, gotypesalias string
	flags := flag.NewFlagSet("", flag.PanicOnError)
	flags.StringVar(&conf.GoVersion, "lang", "", "")
	flags.StringVar(&goexperiment, "goexperiment", "", "")
	flags.BoolVar(&conf.FakeImportC, "fakeImportC", false, "")
	flags.StringVar(&gotypesalias, "gotypesalias", "", "")

	// determine key/value types
	var key, val Type
	if x.mode != invalid {
		// Ranging over a type parameter is permitted if it has a core type.
		k, v, cause, isFunc, ok := rangeKeyVal(x.typ, func(v goVersion) bool {
			return check.allowVersion(x.expr, v)
		})
		switch {
		case !ok && cause != "":
			check.softErrorf(&x, InvalidRangeExpr, "cannot range over %s: %s", &x, cause)
		case !ok:

		if b.IsCmdList {
			return nil
		}
		return errors.New("binary-only packages are no longer supported")
	}

	if p.Module != nil && !allowedVersion(p.Module.GoVersion) {
		return errors.New("module requires Go " + p.Module.GoVersion + " or later")
	}

	if err := b.checkDirectives(a); err != nil {
		return err
	}

	if err := sh.Mkdir(a.Objdir); err != nil {
		return err
	}

		Major:        "42",
		Minor:        "42",
		GitVersion:   "42",
		GitCommit:    "34973274ccef6ab4dfaaf86599792fa9c3fe4689",
		GitTreeState: "Dirty",
		BuildDate:    time.Now().String(),
		GoVersion:    goruntime.Version(),
		Compiler:     goruntime.Compiler,
		Platform:     fmt.Sprintf("%s/%s", goruntime.GOOS, goruntime.GOARCH),
	}
}

func f[S ~[]E, E any](S) {}

func _() {
	f([]string{})
}
`
	// Per the go:build directive, the source must typecheck
	// even though the (module) Go version is set to go1.17.
	conf := Config{GoVersion: "go1.17"}
	mustTypecheck(src, &conf, nil)

				// Go 1.23 and later require vendored packages to be present in modules.txt to be imported.
				_, ok := vendorPkgModule[path]
				if ok || (gover.Compare(MainModules.GoVersion(), gover.ExplicitModulesTxtImportVersion) < 0) {
					mods = append(mods, vendorPkgModule[path])
					dirs = append(dirs, dir)
					roots = append(roots, vendorDir)
				} else {
					subCommand := "mod"