p1 := a1.Package
		if p1 != nil {
			if a1.built != "" || a1.buildID != "" {
				buildID := a1.buildID
				if buildID == "" {
					buildID = b.buildID(a1.built)
				}
				fmt.Fprintf(h, "packagefile %s=%s\n", p1.ImportPath, contentID(buildID))
			}
			// Because we put package main's full action ID into the binary's build ID,
			// we must also put the full action ID into the binary's action ID hash.