return &r
		}
	case *ast.StructType:
		changed := false
		fields := *t.Fields
		fields.List = nil
		for _, f := range t.Fields.List {
			ft := p.rewriteUnsafe(f.Type)
			if ft == f.Type {
				fields.List = append(fields.List, f)
			} else {
				fn := *f
				fn.Type = ft
				fields.List = append(fields.List, &fn)
				changed = true
			}
		}
		if changed {
			r := *t

				Content:  []byte("This small file is in ZIP64 format.\n"),
				Modified: time.Date(2012, 8, 10, 14, 33, 32, 0, time.UTC),
				Mode:     0644,
			},
		},
	},
	// Another zip64 file with different Extras fields. (golang.org/issue/7069)
	{
		Name: "zip64-2.zip",
		File: []ZipTestFile{
			{
				Name:     "README",
				Content:  []byte("This small file is in ZIP64 format.\n"),

func TestFields(t *testing.T) {
	for _, tt := range fieldstests {
		b := []byte(tt.s)
		a := Fields(b)

		// Appending to the results should not change future results.
		var x []byte
		for _, v := range a {
			x = append(v, 'z')
		}

		result := sliceOfString(a)
		if !eq(result, tt.a) {
			t.Errorf("Fields(%q) = %v; want %v", tt.s, a, tt.a)
			continue
		}

		if string(b) != tt.s {