}
		}
		for _, pkg := range pkgs {
			if !load.SafeArg(pkg) {
				return nil, nil, fmt.Errorf("invalid pkg-config package name: %s", pkg)
			}
		}
		var out []byte
		out, err = sh.runOut(p.Dir, nil, b.PkgconfigCmd(), "--cflags", pcflags, "--", pkgs)
		if err != nil {
			desc := b.PkgconfigCmd() + " --cflags " + strings.Join(pcflags, " ") + " -- " + strings.Join(pkgs, " ")