// encoded in the debugging information entry itself.
			val = true

		// reference to other entry
		case formRefAddr:
			vers := b.format.version()
			if vers == 0 {
				b.error("unknown version for DW_FORM_ref_addr")
			} else if vers == 2 {
				val = Offset(b.addr())
			} else {
				is64, known := b.format.dwarf64()
				if !known {
					b.error("unknown size for DW_FORM_ref_addr")

	c := hs.c

	hs.hello = new(serverHelloMsg)

	// TLS 1.3 froze the ServerHello.legacy_version field, and uses
	// supported_versions instead. See RFC 8446, sections 4.1.3 and 4.2.1.
	hs.hello.vers = VersionTLS12
	hs.hello.supportedVersion = c.vers

	if len(hs.clientHello.supportedVersions) == 0 {
		c.sendAlert(alertIllegalParameter)
		return errors.New("tls: client used the legacy version field to negotiate TLS 1.3")
	}

// versions that support signature algorithms, so TLS 1.2 and 1.3.
func selectSignatureScheme(vers uint16, c *Certificate, peerAlgs []SignatureScheme) (SignatureScheme, error) {
	supportedAlgs := signatureSchemesForCertificate(vers, c)
	if len(supportedAlgs) == 0 {
		return 0, unsupportedCertificateError(c)
	}
	if len(peerAlgs) == 0 && vers == VersionTLS12 {
		// For TLS 1.2, if the client didn't send signature_algorithms then we

		if cfg.CmdName != "mod download" {
			vers := mod.Version
			if mod.Path == "golang.org/toolchain" {
				// Shorten v0.0.1-go1.13.1.darwin-amd64 to go1.13.1.darwin-amd64
				_, vers, _ = strings.Cut(vers, "-")
				if i := strings.LastIndex(vers, "."); i >= 0 {
					goos, goarch, _ := strings.Cut(vers[i+1:], "-")
					vers = vers[:i] + " (" + goos + "/" + goarch + ")"
				}

			if !extData.ReadUint8LengthPrefixed(&versList) || versList.Empty() {
				return false
			}
			for !versList.Empty() {
				var vers uint16
				if !versList.ReadUint16(&vers) {
					return false
				}
				m.supportedVersions = append(m.supportedVersions, vers)
			}
		case extensionCookie:
			// RFC 8446, Section 4.2.2
			if !readUint16LengthPrefixed(&extData, &m.cookie) ||
				len(m.cookie) == 0 {

}

func randomString(n int, rand *rand.Rand) string {
	b := randomBytes(n, rand)
	return string(b)
}

func (*clientHelloMsg) Generate(rand *rand.Rand, size int) reflect.Value {
	m := &clientHelloMsg{}
	m.vers = uint16(rand.Intn(65536))
	m.random = randomBytes(32, rand)
	m.sessionId = randomBytes(rand.Intn(32), rand)
	m.cipherSuites = make([]uint16, rand.Intn(63)+1)
	for i := 0; i < len(m.cipherSuites); i++ {

	if err != nil {
		t.Fatal(err)
	}
	hello, ok := msg.(*clientHelloMsg)
	if !ok {
		t.Fatalf("unexpected message type %T", msg)
	}

	if !isBoringVersion(hello.vers) {
		t.Errorf("client vers=%#x, want %#x (TLS 1.2)", hello.vers, VersionTLS12)
	}
	for _, v := range hello.supportedVersions {
		if !isBoringVersion(v) {
			t.Errorf("client offered disallowed version %#x", v)
		}
	}

		path, err := module.UnescapePath(escPath)
		if err != nil {
			reportError(w, err)
			return
		}
		vers, err := module.UnescapeVersion(escVers)
		if err != nil {
			reportError(w, err)
			return
		}
		id, err := s.ops.Lookup(ctx, module.Version{Path: path, Version: vers})
		if err != nil {
			reportError(w, err)
			return
		}
		records, err := s.ops.ReadRecords(ctx, id, 1)
		if err != nil {

	epath, err := module.EscapePath(path)
	if err != nil {
		return nil, err
	}
	evers, err := module.EscapeVersion(strings.TrimSuffix(vers, "/go.mod"))
	if err != nil {
		return nil, err
	}
	remotePath := "/lookup/" + epath + "@" + evers
	file := c.name + remotePath

	// Fetch the data.
	// The lookupCache avoids redundant ReadCache/GetURL operations

	err := readFull(d.r, d.tmp[:13])
	if err != nil {
		return fmt.Errorf("gif: reading header: %v", err)
	}
	d.vers = string(d.tmp[:6])
	if d.vers != "GIF87a" && d.vers != "GIF89a" {
		return fmt.Errorf("gif: can't recognize format %q", d.vers)
	}
	d.width = int(d.tmp[6]) + int(d.tmp[7])<<8
	d.height = int(d.tmp[8]) + int(d.tmp[9])<<8
	if fields := d.tmp[10]; fields&fColorTable != 0 {