if err != nil {
			return
		}

		type file struct {
			header  *FileHeader
			content []byte
		}
		files := []file{}

		for _, f := range r.File {
			fr, err := f.Open()
			if err != nil {
				continue
			}
			content, err := io.ReadAll(fr)
			if err != nil {
				continue
			}
			files = append(files, file{header: &f.FileHeader, content: content})
			if _, err := r.Open(f.Name); err != nil {

//go:linkname runtime_arena_newArena
func runtime_arena_newArena() unsafe.Pointer

//go:linkname runtime_arena_arena_New
func runtime_arena_arena_New(arena unsafe.Pointer, typ any) any

// Mark as noescape to avoid escaping the slice header.
//
//go:noescape
//go:linkname runtime_arena_arena_Slice
func runtime_arena_arena_Slice(arena unsafe.Pointer, slice any, cap int)

//go:linkname runtime_arena_arena_Free

		r := NewReader(bytes.NewReader(b))
		type file struct {
			header  *Header
			content []byte
		}
		files := []file{}
		for {
			hdr, err := r.Next()
			if err == io.EOF {
				break
			}
			if err != nil {
				return
			}
			buf := bytes.NewBuffer(nil)
			if _, err := io.Copy(buf, r); err != nil {
				continue
			}
			files = append(files, file{header: hdr, content: buf.Bytes()})
		}

	m, err := w.Write(b)
	if m > len(b) {
		panic("bytes.Reader.WriteTo: invalid Write count")
	}
	r.i += int64(m)
	n = int64(m)
	if m != len(b) && err == nil {
		err = io.ErrShortWrite
	}
	return
}

// Reset resets the [Reader.Reader] to be reading from b.
func (r *Reader) Reset(b []byte) { *r = Reader{b, 0, -1} }

// NewReader returns a new [Reader.Reader] reading from b.

If the argument to [FileInfoHeader] implements the new [FileInfoNames]
interface, then the interface methods will be used to set the Uname/Gname
of the file header. This allows applications to override the system-dependent

			descsz := f.ByteOrder.Uint32(d[4:])
			typ := f.ByteOrder.Uint32(d[8:])

			an := (namesz + 3) &^ 3
			ad := (descsz + 3) &^ 3

			if int(12+an+ad) > len(d) {
				t.Logf("note section %d too short for header (%d < 12 + align(%d,4) + align(%d,4))", i, len(d), namesz, descsz)
				continue sections
			}

			// 3 == NT_GNU_BUILD_ID
			if typ == 3 && namesz == 4 && bytes.Equal(d[12:16], []byte("GNU\000")) {
				c++
			}

	}
}

var UnreadRuneErrorTests = []struct {
	name string
	f    func(*Reader)
}{
	{"Read", func(r *Reader) { r.Read([]byte{0}) }},
	{"ReadByte", func(r *Reader) { r.ReadByte() }},
	{"UnreadRune", func(r *Reader) { r.UnreadRune() }},
	{"Seek", func(r *Reader) { r.Seek(0, io.SeekCurrent) }},
	{"WriteTo", func(r *Reader) { r.WriteTo(&Buffer{}) }},
}

func TestUnreadRuneError(t *testing.T) {

	case "all", "ret":
		ctxt.Retpoline = true
	}

	ctxt.Bso = bufio.NewWriter(os.Stdout)
	defer ctxt.Bso.Flush()

	architecture.Init(ctxt)

	// Create object file, write header.
	buf, err := bio.Create(*flags.OutputFile)
	if err != nil {
		log.Fatal(err)
	}
	defer buf.Close()

	if !*flags.SymABIs {
		buf.WriteString(objabi.HeaderString())
		fmt.Fprintf(buf, "!\n")
	}

	os.Setenv("GO_ADDR2LINETEST_IS_ADDR2LINE", "1") // Set for subprocesses to inherit.
	os.Exit(m.Run())
}

// addr2linePath returns the path to the "addr2line" binary to run.
func addr2linePath(t testing.TB) string {
	t.Helper()
	testenv.MustHaveExec(t)

	addr2linePathOnce.Do(func() {
		addr2lineExePath, addr2linePathErr = os.Executable()
	})
	if addr2linePathErr != nil {
		t.Fatal(addr2linePathErr)
	}
	return addr2lineExePath
}

	}{
		{"readme.txt", "This archive contains some text files."},
		{"gopher.txt", "Gopher names:\nGeorge\nGeoffrey\nGonzo"},
		{"todo.txt", "Get animal handling license."},
	}
	for _, file := range files {
		hdr := &tar.Header{
			Name: file.Name,
			Mode: 0600,
			Size: int64(len(file.Body)),
		}
		if err := tw.WriteHeader(hdr); err != nil {
			log.Fatal(err)
		}
		if _, err := tw.Write([]byte(file.Body)); err != nil {