base.Fatalf("go: no go.work file found\n\t(run 'go work init' first or specify path using GOWORK environment variable)")
	}

	_, err := modload.LoadModGraph(ctx, "")
	if err != nil {
		toolchain.SwitchOrFatal(ctx, err)
	}
	mustSelectFor := map[module.Version][]module.Version{}

	mms := modload.MainModules

	opts := modload.PackageOpts{
		Tags:                     imports.AnyTags(),
		VendorModulesInGOROOTSrc: true,

	}
	modload.ForceUseModules = true
	modload.RootMode = modload.NeedRoot

	goVersion := graphGo.String()
	if goVersion != "" && gover.Compare(gover.Local(), goVersion) < 0 {
		toolchain.SwitchOrFatal(ctx, &gover.TooNewError{
			What:      "-go flag",
			GoVersion: goVersion,
		})
	}

	mg, err := modload.LoadModGraph(ctx, goVersion)
	if err != nil {
		base.Fatal(err)
	}

	counterSwitchExec.Inc()
	Exec(tv)
	panic("unreachable")
}

var counterSwitchExec = telemetry.NewCounter("go/toolchain/switch-exec")

// SwitchOrFatal attempts a toolchain switch based on the information in err
// and otherwise falls back to base.Fatal(err).
func SwitchOrFatal(ctx context.Context, err error) {
	var s Switcher
	s.Error(err)
	s.Switch(ctx)
	base.Exit()
}

				_, err := modload.LoadModGraph(ctx, "")
				if err != nil {
					// TODO(#64008): call base.Fatalf instead of toolchain.SwitchOrFatal
					// here, since we can only reach this point with an outdated toolchain
					// if the go.mod file is inconsistent.
					toolchain.SwitchOrFatal(ctx, err)
				}

				for _, m := range modFile.Require {
					args = append(args, m.Mod.Path)
				}
			}
		}
	}

	modload.ForceUseModules = true
	modload.RootMode = modload.NeedRoot

	goVersion := tidyGo.String()
	if goVersion != "" && gover.Compare(gover.Local(), goVersion) < 0 {
		toolchain.SwitchOrFatal(ctx, &gover.TooNewError{
			What:      "-go flag",
			GoVersion: goVersion,
		})
	}

	modload.LoadPackages(ctx, modload.PackageOpts{
		TidyGoVersion:            tidyGo.String(),

		// when all the required modules are old enough
		// but the command line is not.
		// TODO(bcmills): modload.EditBuildList should catch this instead,
		// and then this can be changed to base.Fatal(err).
		toolchain.SwitchOrFatal(ctx, err)
	}

	newReqs := reqsFromGoMod(modload.ModFile())
	r.reportChanges(oldReqs, newReqs)

	if gowork := modload.FindGoWork(base.Cwd()); gowork != "" {
		wf, err := modload.ReadWorkFile(gowork)

	if errors.Is(err, gover.ErrTooNew) {
		// Run early switch, same one go install or go run would eventually do,
		// if it understood all the command-line flags.
		SwitchOrFatal(ctx, err)
	}

	return true // pkg@version found