if err != nil {
			// If we couldn't load the graph, we don't know what its requirements were
			// to begin with, so we can't edit those requirements in a coherent way.
			return orig, false, err
		}
		bl := mg.BuildList()[MainModules.Len():]
		selectedRoot = make(map[string]string, len(bl))
		for _, m := range bl {
			selectedRoot[m.Path] = m.Version
		}
	}

	for _, r := range tryUpgrade {