r.reportChanges(oldReqs, newReqs)

	if gowork := modload.FindGoWork(base.Cwd()); gowork != "" {
		wf, err := modload.ReadWorkFile(gowork)
		if err == nil && modload.UpdateWorkGoVersion(wf, modload.MainModules.GoVersion()) {
			modload.WriteWorkFile(gowork, wf)
		}
	}
}

// parseArgs parses command-line arguments and reports errors.
//
// The command-line arguments are of the form path@version or simply path, with