libgo: Update to October 24 version of master library.

From-SVN: r204466

35 files changed, 2684 insertions, 664 deletions

diff --git a/libgo/go/encoding/asn1/asn1.go b/libgo/go/encoding/asn1/asn1.go
index cac9d64..992356c 100644
--- a/libgo/go/encoding/asn1/asn1.go
+++ b/libgo/go/encoding/asn1/asn1.go
@@ -32,14 +32,14 @@ type StructuralError struct {
 	Msg string
 }
 
-func (e StructuralError) Error() string { return "ASN.1 structure error: " + e.Msg }
+func (e StructuralError) Error() string { return "asn1: structure error: " + e.Msg }
 
 // A SyntaxError suggests that the ASN.1 data is invalid.
 type SyntaxError struct {
 	Msg string
 }
 
-func (e SyntaxError) Error() string { return "ASN.1 syntax error: " + e.Msg }
+func (e SyntaxError) Error() string { return "asn1: syntax error: " + e.Msg }
 
 // We start by dealing with each of the primitive types in turn.
 
@@ -51,7 +51,19 @@ func parseBool(bytes []byte) (ret bool, err error) {
 		return
 	}
 
-	return bytes[0] != 0, nil
+	// DER demands that "If the encoding represents the boolean value TRUE,
+	// its single contents octet shall have all eight bits set to one."
+	// Thus only 0 and 255 are valid encoded values.
+	switch bytes[0] {
+	case 0:
+		ret = false
+	case 0xff:
+		ret = true
+	default:
+		err = SyntaxError{"invalid boolean"}
+	}
+
+	return
 }
 
 // INTEGER
@@ -171,7 +183,7 @@ func parseBitString(bytes []byte) (ret BitString, err error) {
 // An ObjectIdentifier represents an ASN.1 OBJECT IDENTIFIER.
 type ObjectIdentifier []int
 
-// Equal returns true iff oi and other represent the same identifier.
+// Equal reports whether oi and other represent the same identifier.
 func (oi ObjectIdentifier) Equal(other ObjectIdentifier) bool {
 	if len(oi) != len(other) {
 		return false
@@ -198,12 +210,24 @@ func parseObjectIdentifier(bytes []byte) (s []int, err error) {
 	// encoded differently) and then every varint is a single byte long.
 	s = make([]int, len(bytes)+1)
 
-	// The first byte is 40*value1 + value2:
-	s[0] = int(bytes[0]) / 40
-	s[1] = int(bytes[0]) % 40
+	// The first varint is 40*value1 + value2:
+	// According to this packing, value1 can take the values 0, 1 and 2 only.
+	// When value1 = 0 or value1 = 1, then value2 is <= 39. When value1 = 2,
+	// then there are no restrictions on value2.
+	v, offset, err := parseBase128Int(bytes, 0)
+	if err != nil {
+		return
+	}
+	if v < 80 {
+		s[0] = v / 40
+		s[1] = v % 40
+	} else {
+		s[0] = 2
+		s[1] = v - 80
+	}
+
 	i := 2
-	for offset := 1; offset < len(bytes); i++ {
-		var v int
+	for ; offset < len(bytes); i++ {
 		v, offset, err = parseBase128Int(bytes, offset)
 		if err != nil {
 			return
@@ -573,7 +597,7 @@ func parseField(v reflect.Value, bytes []byte, initOffset int, params fieldParam
 				}
 			} else {
 				if fieldType != flagType {
-					err = StructuralError{"Zero length explicit tag was not an asn1.Flag"}
+					err = StructuralError{"zero length explicit tag was not an asn1.Flag"}
 					return
 				}
 				v.SetBool(true)
diff --git a/libgo/go/encoding/asn1/asn1_test.go b/libgo/go/encoding/asn1/asn1_test.go
index 6e98dcf..f68804e 100644
--- a/libgo/go/encoding/asn1/asn1_test.go
+++ b/libgo/go/encoding/asn1/asn1_test.go
@@ -12,6 +12,32 @@ import (
 	"time"
 )
 
+type boolTest struct {
+	in  []byte
+	ok  bool
+	out bool
+}
+
+var boolTestData = []boolTest{
+	{[]byte{0x00}, true, false},
+	{[]byte{0xff}, true, true},
+	{[]byte{0x00, 0x00}, false, false},
+	{[]byte{0xff, 0xff}, false, false},
+	{[]byte{0x01}, false, false},
+}
+
+func TestParseBool(t *testing.T) {
+	for i, test := range boolTestData {
+		ret, err := parseBool(test.in)
+		if (err == nil) != test.ok {
+			t.Errorf("#%d: Incorrect error result (did fail? %v, expected: %v)", i, err == nil, test.ok)
+		}
+		if test.ok && ret != test.out {
+			t.Errorf("#%d: Bad result: %v (expected %v)", i, ret, test.out)
+		}
+	}
+}
+
 type int64Test struct {
 	in  []byte
 	ok  bool
@@ -183,6 +209,7 @@ var objectIdentifierTestData = []objectIdentifierTest{
 	{[]byte{85}, true, []int{2, 5}},
 	{[]byte{85, 0x02}, true, []int{2, 5, 2}},
 	{[]byte{85, 0x02, 0xc0, 0x00}, true, []int{2, 5, 2, 0x2000}},
+	{[]byte{0x81, 0x34, 0x03}, true, []int{2, 100, 3}},
 	{[]byte{85, 0x02, 0xc0, 0x80, 0x80, 0x80, 0x80}, false, []int{}},
 }
 
@@ -378,7 +405,7 @@ var unmarshalTestData = []struct {
 	{[]byte{0x30, 0x03, 0x81, 0x01, 0x01}, &TestContextSpecificTags{1}},
 	{[]byte{0x30, 0x08, 0xa1, 0x03, 0x02, 0x01, 0x01, 0x02, 0x01, 0x02}, &TestContextSpecificTags2{1, 2}},
 	{[]byte{0x01, 0x01, 0x00}, newBool(false)},
-	{[]byte{0x01, 0x01, 0x01}, newBool(true)},
+	{[]byte{0x01, 0x01, 0xff}, newBool(true)},
 	{[]byte{0x30, 0x0b, 0x13, 0x03, 0x66, 0x6f, 0x6f, 0x02, 0x01, 0x22, 0x02, 0x01, 0x33}, &TestElementsAfterString{"foo", 0x22, 0x33}},
 	{[]byte{0x30, 0x05, 0x02, 0x03, 0x12, 0x34, 0x56}, &TestBigInt{big.NewInt(0x123456)}},
 }
diff --git a/libgo/go/encoding/asn1/marshal.go b/libgo/go/encoding/asn1/marshal.go
index adaf80d..ed17e41 100644
--- a/libgo/go/encoding/asn1/marshal.go
+++ b/libgo/go/encoding/asn1/marshal.go
@@ -240,11 +240,11 @@ func marshalBitString(out *forkableWriter, b BitString) (err error) {
 }
 
 func marshalObjectIdentifier(out *forkableWriter, oid []int) (err error) {
-	if len(oid) < 2 || oid[0] > 6 || oid[1] >= 40 {
+	if len(oid) < 2 || oid[0] > 2 || (oid[0] < 2 && oid[1] >= 40) {
 		return StructuralError{"invalid object identifier"}
 	}
 
-	err = out.WriteByte(byte(oid[0]*40 + oid[1]))
+	err = marshalBase128Int(out, int64(oid[0]*40+oid[1]))
 	if err != nil {
 		return
 	}
@@ -304,7 +304,7 @@ func marshalUTCTime(out *forkableWriter, t time.Time) (err error) {
 	case 2000 <= year && year < 2050:
 		err = marshalTwoDigits(out, int(year-2000))
 	default:
-		return StructuralError{"Cannot represent time as UTCTime"}
+		return StructuralError{"cannot represent time as UTCTime"}
 	}
 	if err != nil {
 		return
@@ -441,11 +441,11 @@ func marshalBody(out *forkableWriter, value reflect.Value, params fieldParameter
 			return
 		}
 
-		var params fieldParameters
+		var fp fieldParameters
 		for i := 0; i < v.Len(); i++ {
 			var pre *forkableWriter
 			pre, out = out.fork()
-			err = marshalField(pre, v.Index(i), params)
+			err = marshalField(pre, v.Index(i), fp)
 			if err != nil {
 				return
 			}
@@ -501,7 +501,7 @@ func marshalField(out *forkableWriter, v reflect.Value, params fieldParameters)
 	class := classUniversal
 
 	if params.stringType != 0 && tag != tagPrintableString {
-		return StructuralError{"Explicit string type given to non-string member"}
+		return StructuralError{"explicit string type given to non-string member"}
 	}
 
 	if tag == tagPrintableString {
@@ -525,7 +525,7 @@ func marshalField(out *forkableWriter, v reflect.Value, params fieldParameters)
 
 	if params.set {
 		if tag != tagSequence {
-			return StructuralError{"Non sequence tagged as set"}
+			return StructuralError{"non sequence tagged as set"}
 		}
 		tag = tagSet
 	}
diff --git a/libgo/go/encoding/asn1/marshal_test.go b/libgo/go/encoding/asn1/marshal_test.go
index b4dbe71..763c86d 100644
--- a/libgo/go/encoding/asn1/marshal_test.go
+++ b/libgo/go/encoding/asn1/marshal_test.go
@@ -87,6 +87,7 @@ var marshalTests = []marshalTest{
 	{BitString{[]byte{0x81, 0xf0}, 12}, "03030481f0"},
 	{ObjectIdentifier([]int{1, 2, 3, 4}), "06032a0304"},
 	{ObjectIdentifier([]int{1, 2, 840, 133549, 1, 1, 5}), "06092a864888932d010105"},
+	{ObjectIdentifier([]int{2, 100, 3}), "0603813403"},
 	{"test", "130474657374"},
 	{
 		"" +
diff --git a/libgo/go/encoding/binary/binary.go b/libgo/go/encoding/binary/binary.go
index edbac19..f3466b9 100644
--- a/libgo/go/encoding/binary/binary.go
+++ b/libgo/go/encoding/binary/binary.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package binary implements translation between numbers and byte sequences
-// and encoding and decoding of varints.
+// Package binary implements simple translation between numbers and byte
+// sequences and encoding and decoding of varints.
 //
 // Numbers are translated by reading and writing fixed-size values.
 // A fixed-size value is either a fixed-size arithmetic
@@ -13,6 +13,11 @@
 // Varints are a method of encoding integers using one or more bytes;
 // numbers with smaller absolute value take a smaller number of bytes.
 // For a specification, see http://code.google.com/apis/protocolbuffers/docs/encoding.html.
+//
+// This package favors simplicity over efficiency. Clients that require
+// high-performance serialization, especially for large data structures,
+// should look at more advanced solutions such as the encoding/gob
+// package or protocol buffers.
 package binary
 
 import (
@@ -129,30 +134,65 @@ func (bigEndian) GoString() string { return "binary.BigEndian" }
 // blank (_) field names is skipped; i.e., blank field names
 // may be used for padding.
 func Read(r io.Reader, order ByteOrder, data interface{}) error {
-	// Fast path for basic types.
-	if n := intDestSize(data); n != 0 {
+	// Fast path for basic types and slices.
+	if n := intDataSize(data); n != 0 {
 		var b [8]byte
-		bs := b[:n]
+		var bs []byte
+		if n > len(b) {
+			bs = make([]byte, n)
+		} else {
+			bs = b[:n]
+		}
 		if _, err := io.ReadFull(r, bs); err != nil {
 			return err
 		}
-		switch v := data.(type) {
+		switch data := data.(type) {
 		case *int8:
-			*v = int8(b[0])
+			*data = int8(b[0])
 		case *uint8:
-			*v = b[0]
+			*data = b[0]
 		case *int16:
-			*v = int16(order.Uint16(bs))
+			*data = int16(order.Uint16(bs))
 		case *uint16:
-			*v = order.Uint16(bs)
+			*data = order.Uint16(bs)
 		case *int32:
-			*v = int32(order.Uint32(bs))
+			*data = int32(order.Uint32(bs))
 		case *uint32:
-			*v = order.Uint32(bs)
+			*data = order.Uint32(bs)
 		case *int64:
-			*v = int64(order.Uint64(bs))
+			*data = int64(order.Uint64(bs))
 		case *uint64:
-			*v = order.Uint64(bs)
+			*data = order.Uint64(bs)
+		case []int8:
+			for i, x := range bs { // Easier to loop over the input for 8-bit values.
+				data[i] = int8(x)
+			}
+		case []uint8:
+			copy(data, bs)
+		case []int16:
+			for i := range data {
+				data[i] = int16(order.Uint16(bs[2*i:]))
+			}
+		case []uint16:
+			for i := range data {
+				data[i] = order.Uint16(bs[2*i:])
+			}
+		case []int32:
+			for i := range data {
+				data[i] = int32(order.Uint32(bs[4*i:]))
+			}
+		case []uint32:
+			for i := range data {
+				data[i] = order.Uint32(bs[4*i:])
+			}
+		case []int64:
+			for i := range data {
+				data[i] = int64(order.Uint64(bs[8*i:]))
+			}
+		case []uint64:
+			for i := range data {
+				data[i] = order.Uint64(bs[8*i:])
+			}
 		}
 		return nil
 	}
@@ -187,60 +227,95 @@ func Read(r io.Reader, order ByteOrder, data interface{}) error {
 // When writing structs, zero values are written for fields
 // with blank (_) field names.
 func Write(w io.Writer, order ByteOrder, data interface{}) error {
-	// Fast path for basic types.
-	var b [8]byte
-	var bs []byte
-	switch v := data.(type) {
-	case *int8:
-		bs = b[:1]
-		b[0] = byte(*v)
-	case int8:
-		bs = b[:1]
-		b[0] = byte(v)
-	case *uint8:
-		bs = b[:1]
-		b[0] = *v
-	case uint8:
-		bs = b[:1]
-		b[0] = byte(v)
-	case *int16:
-		bs = b[:2]
-		order.PutUint16(bs, uint16(*v))
-	case int16:
-		bs = b[:2]
-		order.PutUint16(bs, uint16(v))
-	case *uint16:
-		bs = b[:2]
-		order.PutUint16(bs, *v)
-	case uint16:
-		bs = b[:2]
-		order.PutUint16(bs, v)
-	case *int32:
-		bs = b[:4]
-		order.PutUint32(bs, uint32(*v))
-	case int32:
-		bs = b[:4]
-		order.PutUint32(bs, uint32(v))
-	case *uint32:
-		bs = b[:4]
-		order.PutUint32(bs, *v)
-	case uint32:
-		bs = b[:4]
-		order.PutUint32(bs, v)
-	case *int64:
-		bs = b[:8]
-		order.PutUint64(bs, uint64(*v))
-	case int64:
-		bs = b[:8]
-		order.PutUint64(bs, uint64(v))
-	case *uint64:
-		bs = b[:8]
-		order.PutUint64(bs, *v)
-	case uint64:
-		bs = b[:8]
-		order.PutUint64(bs, v)
-	}
-	if bs != nil {
+	// Fast path for basic types and slices.
+	if n := intDataSize(data); n != 0 {
+		var b [8]byte
+		var bs []byte
+		if n > len(b) {
+			bs = make([]byte, n)
+		} else {
+			bs = b[:n]
+		}
+		switch v := data.(type) {
+		case *int8:
+			bs = b[:1]
+			b[0] = byte(*v)
+		case int8:
+			bs = b[:1]
+			b[0] = byte(v)
+		case []int8:
+			for i, x := range v {
+				bs[i] = byte(x)
+			}
+		case *uint8:
+			bs = b[:1]
+			b[0] = *v
+		case uint8:
+			bs = b[:1]
+			b[0] = byte(v)
+		case []uint8:
+			bs = v
+		case *int16:
+			bs = b[:2]
+			order.PutUint16(bs, uint16(*v))
+		case int16:
+			bs = b[:2]
+			order.PutUint16(bs, uint16(v))
+		case []int16:
+			for i, x := range v {
+				order.PutUint16(bs[2*i:], uint16(x))
+			}
+		case *uint16:
+			bs = b[:2]
+			order.PutUint16(bs, *v)
+		case uint16:
+			bs = b[:2]
+			order.PutUint16(bs, v)
+		case []uint16:
+			for i, x := range v {
+				order.PutUint16(bs[2*i:], x)
+			}
+		case *int32:
+			bs = b[:4]
+			order.PutUint32(bs, uint32(*v))
+		case int32:
+			bs = b[:4]
+			order.PutUint32(bs, uint32(v))
+		case []int32:
+			for i, x := range v {
+				order.PutUint32(bs[4*i:], uint32(x))
+			}
+		case *uint32:
+			bs = b[:4]
+			order.PutUint32(bs, *v)
+		case uint32:
+			bs = b[:4]
+			order.PutUint32(bs, v)
+		case []uint32:
+			for i, x := range v {
+				order.PutUint32(bs[4*i:], x)
+			}
+		case *int64:
+			bs = b[:8]
+			order.PutUint64(bs, uint64(*v))
+		case int64:
+			bs = b[:8]
+			order.PutUint64(bs, uint64(v))
+		case []int64:
+			for i, x := range v {
+				order.PutUint64(bs[8*i:], uint64(x))
+			}
+		case *uint64:
+			bs = b[:8]
+			order.PutUint64(bs, *v)
+		case uint64:
+			bs = b[:8]
+			order.PutUint64(bs, v)
+		case []uint64:
+			for i, x := range v {
+				order.PutUint64(bs[8*i:], x)
+			}
+		}
 		_, err := w.Write(bs)
 		return err
 	}
@@ -530,18 +605,34 @@ func (e *encoder) skip(v reflect.Value) {
 	e.buf = e.buf[n:]
 }
 
-// intDestSize returns the size of the integer that ptrType points to,
-// or 0 if the type is not supported.
-func intDestSize(ptrType interface{}) int {
-	switch ptrType.(type) {
-	case *int8, *uint8:
+// intDataSize returns the size of the data required to represent the data when encoded.
+// It returns zero if the type cannot be implemented by the fast path in Read or Write.
+func intDataSize(data interface{}) int {
+	switch data := data.(type) {
+	case int8, *int8, *uint8:
 		return 1
-	case *int16, *uint16:
+	case []int8:
+		return len(data)
+	case []uint8:
+		return len(data)
+	case int16, *int16, *uint16:
 		return 2
-	case *int32, *uint32:
+	case []int16:
+		return 2 * len(data)
+	case []uint16:
+		return 2 * len(data)
+	case int32, *int32, *uint32:
 		return 4
-	case *int64, *uint64:
+	case []int32:
+		return 4 * len(data)
+	case []uint32:
+		return 4 * len(data)
+	case int64, *int64, *uint64:
 		return 8
+	case []int64:
+		return 8 * len(data)
+	case []uint64:
+		return 8 * len(data)
 	}
 	return 0
 }
diff --git a/libgo/go/encoding/binary/binary_test.go b/libgo/go/encoding/binary/binary_test.go
index 056f099..fdfee7d 100644
--- a/libgo/go/encoding/binary/binary_test.go
+++ b/libgo/go/encoding/binary/binary_test.go
@@ -141,6 +141,52 @@ func TestWriteSlice(t *testing.T) {
 	checkResult(t, "WriteSlice", BigEndian, err, buf.Bytes(), src)
 }
 
+// Addresses of arrays are easier to manipulate with reflection than are slices.
+var intArrays = []interface{}{
+	&[100]int8{},
+	&[100]int16{},
+	&[100]int32{},
+	&[100]int64{},
+	&[100]uint8{},
+	&[100]uint16{},
+	&[100]uint32{},
+	&[100]uint64{},
+}
+
+func TestSliceRoundTrip(t *testing.T) {
+	buf := new(bytes.Buffer)
+	for _, array := range intArrays {
+		src := reflect.ValueOf(array).Elem()
+		unsigned := false
+		switch src.Index(0).Kind() {
+		case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+			unsigned = true
+		}
+		for i := 0; i < src.Len(); i++ {
+			if unsigned {
+				src.Index(i).SetUint(uint64(i * 0x07654321))
+			} else {
+				src.Index(i).SetInt(int64(i * 0x07654321))
+			}
+		}
+		buf.Reset()
+		srcSlice := src.Slice(0, src.Len())
+		err := Write(buf, BigEndian, srcSlice.Interface())
+		if err != nil {
+			t.Fatal(err)
+		}
+		dst := reflect.New(src.Type()).Elem()
+		dstSlice := dst.Slice(0, dst.Len())
+		err = Read(buf, BigEndian, dstSlice.Interface())
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !reflect.DeepEqual(src.Interface(), dst.Interface()) {
+			t.Fatal(src)
+		}
+	}
+}
+
 func TestWriteT(t *testing.T) {
 	buf := new(bytes.Buffer)
 	ts := T{}
@@ -312,3 +358,16 @@ func BenchmarkWriteInts(b *testing.B) {
 		b.Fatalf("first half doesn't match: %x %x", buf.Bytes(), big[:30])
 	}
 }
+
+func BenchmarkWriteSlice1000Int32s(b *testing.B) {
+	slice := make([]int32, 1000)
+	buf := new(bytes.Buffer)
+	var w io.Writer = buf
+	b.SetBytes(4 * 1000)
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		buf.Reset()
+		Write(w, BigEndian, slice)
+	}
+	b.StopTimer()
+}
diff --git a/libgo/go/encoding/csv/reader.go b/libgo/go/encoding/csv/reader.go
index b099caf..b328dcc 100644
--- a/libgo/go/encoding/csv/reader.go
+++ b/libgo/go/encoding/csv/reader.go
@@ -72,7 +72,7 @@ func (e *ParseError) Error() string {
 
 // These are the errors that can be returned in ParseError.Error
 var (
-	ErrTrailingComma = errors.New("extra delimiter at end of line")
+	ErrTrailingComma = errors.New("extra delimiter at end of line") // no longer used
 	ErrBareQuote     = errors.New("bare \" in non-quoted-field")
 	ErrQuote         = errors.New("extraneous \" in field")
 	ErrFieldCount    = errors.New("wrong number of fields in line")
@@ -98,16 +98,14 @@ var (
 // If LazyQuotes is true, a quote may appear in an unquoted field and a
 // non-doubled quote may appear in a quoted field.
 //
-// If TrailingComma is true, the last field may be an unquoted empty field.
-//
 // If TrimLeadingSpace is true, leading white space in a field is ignored.
 type Reader struct {
-	Comma            rune // Field delimiter (set to ',' by NewReader)
-	Comment          rune // Comment character for start of line
-	FieldsPerRecord  int  // Number of expected fields per record
-	LazyQuotes       bool // Allow lazy quotes
-	TrailingComma    bool // Allow trailing comma
-	TrimLeadingSpace bool // Trim leading space
+	Comma            rune // field delimiter (set to ',' by NewReader)
+	Comment          rune // comment character for start of line
+	FieldsPerRecord  int  // number of expected fields per record
+	LazyQuotes       bool // allow lazy quotes
+	TrailingComma    bool // ignored; here for backwards compatibility
+	TrimLeadingSpace bool // trim leading space
 	line             int
 	column           int
 	r                *bufio.Reader
@@ -257,23 +255,15 @@ func (r *Reader) parseField() (haveField bool, delim rune, err error) {
 	r.field.Reset()
 
 	r1, err := r.readRune()
-	if err != nil {
-		// If we have EOF and are not at the start of a line
-		// then we return the empty field.  We have already
-		// checked for trailing commas if needed.
-		if err == io.EOF && r.column != 0 {
-			return true, 0, err
-		}
-		return false, 0, err
+	for err == nil && r.TrimLeadingSpace && r1 != '\n' && unicode.IsSpace(r1) {
+		r1, err = r.readRune()
 	}
 
-	if r.TrimLeadingSpace {
-		for r1 != '\n' && unicode.IsSpace(r1) {
-			r1, err = r.readRune()
-			if err != nil {
-				return false, 0, err
-			}
-		}
+	if err == io.EOF && r.column != 0 {
+		return true, 0, err
+	}
+	if err != nil {
+		return false, 0, err
 	}
 
 	switch r1 {
@@ -349,25 +339,5 @@ func (r *Reader) parseField() (haveField bool, delim rune, err error) {
 		return false, 0, err
 	}
 
-	if !r.TrailingComma {
-		// We don't allow trailing commas.  See if we
-		// are at the end of the line (being mindful
-		// of trimming spaces).
-		c := r.column
-		r1, err = r.readRune()
-		if r.TrimLeadingSpace {
-			for r1 != '\n' && unicode.IsSpace(r1) {
-				r1, err = r.readRune()
-				if err != nil {
-					break
-				}
-			}
-		}
-		if err == io.EOF || r1 == '\n' {
-			r.column = c // report the comma
-			return false, 0, r.error(ErrTrailingComma)
-		}
-		r.unreadRune()
-	}
 	return true, r1, nil
 }
diff --git a/libgo/go/encoding/csv/reader_test.go b/libgo/go/encoding/csv/reader_test.go
index 5fd84a7..123df06 100644
--- a/libgo/go/encoding/csv/reader_test.go
+++ b/libgo/go/encoding/csv/reader_test.go
@@ -171,32 +171,32 @@ field"`,
 		Output: [][]string{{"a", "b", "c"}, {"d", "e"}},
 	},
 	{
-		Name:  "BadTrailingCommaEOF",
-		Input: "a,b,c,",
-		Error: "extra delimiter at end of line", Line: 1, Column: 5,
+		Name:   "TrailingCommaEOF",
+		Input:  "a,b,c,",
+		Output: [][]string{{"a", "b", "c", ""}},
 	},
 	{
-		Name:  "BadTrailingCommaEOL",
-		Input: "a,b,c,\n",
-		Error: "extra delimiter at end of line", Line: 1, Column: 5,
+		Name:   "TrailingCommaEOL",
+		Input:  "a,b,c,\n",
+		Output: [][]string{{"a", "b", "c", ""}},
 	},
 	{
-		Name:             "BadTrailingCommaSpaceEOF",
+		Name:             "TrailingCommaSpaceEOF",
 		TrimLeadingSpace: true,
 		Input:            "a,b,c, ",
-		Error:            "extra delimiter at end of line", Line: 1, Column: 5,
+		Output:           [][]string{{"a", "b", "c", ""}},
 	},
 	{
-		Name:             "BadTrailingCommaSpaceEOL",
+		Name:             "TrailingCommaSpaceEOL",
 		TrimLeadingSpace: true,
 		Input:            "a,b,c, \n",
-		Error:            "extra delimiter at end of line", Line: 1, Column: 5,
+		Output:           [][]string{{"a", "b", "c", ""}},
 	},
 	{
-		Name:             "BadTrailingCommaLine3",
+		Name:             "TrailingCommaLine3",
 		TrimLeadingSpace: true,
 		Input:            "a,b,c\nd,e,f\ng,hi,",
-		Error:            "extra delimiter at end of line", Line: 3, Column: 4,
+		Output:           [][]string{{"a", "b", "c"}, {"d", "e", "f"}, {"g", "hi", ""}},
 	},
 	{
 		Name:   "NotTrailingComma3",
@@ -231,7 +231,7 @@ x,,,
 		},
 	},
 	{
-		Name:             "Issue 2366",
+		Name:             "TrailingCommaIneffective1",
 		TrailingComma:    true,
 		TrimLeadingSpace: true,
 		Input:            "a,b,\nc,d,e",
@@ -241,11 +241,14 @@ x,,,
 		},
 	},
 	{
-		Name:             "Issue 2366a",
+		Name:             "TrailingCommaIneffective2",
 		TrailingComma:    false,
 		TrimLeadingSpace: true,
 		Input:            "a,b,\nc,d,e",
-		Error:            "extra delimiter at end of line",
+		Output: [][]string{
+			{"a", "b", ""},
+			{"c", "d", "e"},
+		},
 	},
 }
 
diff --git a/libgo/go/encoding/encoding.go b/libgo/go/encoding/encoding.go
new file mode 100644
index 0000000..6d218071
--- /dev/null
+++ b/libgo/go/encoding/encoding.go
@@ -0,0 +1,48 @@
+// Copyright 2013 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package encoding defines interfaces shared by other packages that
+// convert data to and from byte-level and textual representations.
+// Packages that check for these interfaces include encoding/gob,
+// encoding/json, and encoding/xml. As a result, implementing an
+// interface once can make a type useful in multiple encodings.
+// Standard types that implement these interfaces include time.Time and net.IP.
+// The interfaces come in pairs that produce and consume encoded data.
+package encoding
+
+// BinaryMarshaler is the interface implemented by an object that can
+// marshal itself into a binary form.
+//
+// MarshalBinary encodes the receiver into a binary form and returns the result.
+type BinaryMarshaler interface {
+	MarshalBinary() (data []byte, err error)
+}
+
+// BinaryUnmarshaler is the interface implemented by an object that can
+// unmarshal a binary representation of itself.
+//
+// UnmarshalBinary must be able to decode the form generated by MarshalBinary.
+// UnmarshalBinary must copy the data if it wishes to retain the data
+// after returning.
+type BinaryUnmarshaler interface {
+	UnmarshalBinary(data []byte) error
+}
+
+// TextMarshaler is the interface implemented by an object that can
+// marshal itself into a textual form.
+//
+// MarshalText encodes the receiver into UTF-8-encoded text and returns the result.
+type TextMarshaler interface {
+	MarshalText() (text []byte, err error)
+}
+
+// TextUnmarshaler is the interface implemented by an object that can
+// unmarshal a textual representation of itself.
+//
+// UnmarshalText must be able to decode the form generated by MarshalText.
+// UnmarshalText must copy the text if it wishes to retain the text
+// after returning.
+type TextUnmarshaler interface {
+	UnmarshalText(text []byte) error
+}
diff --git a/libgo/go/encoding/gob/codec_test.go b/libgo/go/encoding/gob/codec_test.go
index 9e38e31..b40f783 100644
--- a/libgo/go/encoding/gob/codec_test.go
+++ b/libgo/go/encoding/gob/codec_test.go
@@ -1009,24 +1009,6 @@ func TestBadRecursiveType(t *testing.T) {
 	// Can't test decode easily because we can't encode one, so we can't pass one to a Decoder.
 }
 
-type Bad0 struct {
-	CH chan int
-	C  float64
-}
-
-func TestInvalidField(t *testing.T) {
-	var bad0 Bad0
-	bad0.CH = make(chan int)
-	b := new(bytes.Buffer)
-	dummyEncoder := new(Encoder) // sufficient for this purpose.
-	dummyEncoder.encode(b, reflect.ValueOf(&bad0), userType(reflect.TypeOf(&bad0)))
-	if err := dummyEncoder.err; err == nil {
-		t.Error("expected error; got none")
-	} else if strings.Index(err.Error(), "type") < 0 {
-		t.Error("expected type error; got", err)
-	}
-}
-
 type Indirect struct {
 	A ***[3]int
 	S ***[]int
diff --git a/libgo/go/encoding/gob/debug.go b/libgo/go/encoding/gob/debug.go
index 31d1351..6117eb0 100644
--- a/libgo/go/encoding/gob/debug.go
+++ b/libgo/go/encoding/gob/debug.go
@@ -415,6 +415,16 @@ func (deb *debugger) typeDefinition(indent tab, id typeId) {
 		deb.delta(1)
 		com := deb.common()
 		wire.GobEncoderT = &gobEncoderType{com}
+	case 5: // BinaryMarshaler type, one field of {{Common}}
+		// Field number 0 is CommonType
+		deb.delta(1)
+		com := deb.common()
+		wire.BinaryMarshalerT = &gobEncoderType{com}
+	case 6: // TextMarshaler type, one field of {{Common}}
+		// Field number 0 is CommonType
+		deb.delta(1)
+		com := deb.common()
+		wire.TextMarshalerT = &gobEncoderType{com}
 	default:
 		errorf("bad field in type %d", fieldNum)
 	}
diff --git a/libgo/go/encoding/gob/decode.go b/libgo/go/encoding/gob/decode.go
index 7cc7565..3e76f4c 100644
--- a/libgo/go/encoding/gob/decode.go
+++ b/libgo/go/encoding/gob/decode.go
@@ -9,6 +9,7 @@ package gob
 
 import (
 	"bytes"
+	"encoding"
 	"errors"
 	"io"
 	"math"
@@ -450,11 +451,11 @@ type decEngine struct {
 
 // allocate makes sure storage is available for an object of underlying type rtyp
 // that is indir levels of indirection through p.
-func allocate(rtyp reflect.Type, p uintptr, indir int) uintptr {
+func allocate(rtyp reflect.Type, p unsafe.Pointer, indir int) unsafe.Pointer {
 	if indir == 0 {
 		return p
 	}
-	up := unsafe.Pointer(p)
+	up := p
 	if indir > 1 {
 		up = decIndirect(up, indir)
 	}
@@ -462,13 +463,13 @@ func allocate(rtyp reflect.Type, p uintptr, indir int) uintptr {
 		// Allocate object.
 		*(*unsafe.Pointer)(up) = unsafe.Pointer(reflect.New(rtyp).Pointer())
 	}
-	return *(*uintptr)(up)
+	return *(*unsafe.Pointer)(up)
 }
 
 // decodeSingle decodes a top-level value that is not a struct and stores it through p.
 // Such values are preceded by a zero, making them have the memory layout of a
 // struct field (although with an illegal field number).
-func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, basep uintptr) {
+func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, basep unsafe.Pointer) {
 	state := dec.newDecoderState(&dec.buf)
 	state.fieldnum = singletonField
 	delta := int(state.decodeUint())
@@ -479,7 +480,7 @@ func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, basep uint
 	if instr.indir != ut.indir {
 		errorf("internal error: inconsistent indirection instr %d ut %d", instr.indir, ut.indir)
 	}
-	ptr := unsafe.Pointer(basep) // offset will be zero
+	ptr := basep // offset will be zero
 	if instr.indir > 1 {
 		ptr = decIndirect(ptr, instr.indir)
 	}
@@ -492,7 +493,7 @@ func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, basep uint
 // differ from ut.indir, which was computed when the engine was built.
 // This state cannot arise for decodeSingle, which is called directly
 // from the user's value, not from the innards of an engine.
-func (dec *Decoder) decodeStruct(engine *decEngine, ut *userTypeInfo, p uintptr, indir int) {
+func (dec *Decoder) decodeStruct(engine *decEngine, ut *userTypeInfo, p unsafe.Pointer, indir int) {
 	p = allocate(ut.base, p, indir)
 	state := dec.newDecoderState(&dec.buf)
 	state.fieldnum = -1
@@ -511,7 +512,7 @@ func (dec *Decoder) decodeStruct(engine *decEngine, ut *userTypeInfo, p uintptr,
 			break
 		}
 		instr := &engine.instr[fieldnum]
-		p := unsafe.Pointer(basep + instr.offset)
+		p := unsafe.Pointer(uintptr(basep) + instr.offset)
 		if instr.indir > 1 {
 			p = decIndirect(p, instr.indir)
 		}
@@ -559,25 +560,25 @@ func (dec *Decoder) ignoreSingle(engine *decEngine) {
 }
 
 // decodeArrayHelper does the work for decoding arrays and slices.
-func (dec *Decoder) decodeArrayHelper(state *decoderState, p uintptr, elemOp decOp, elemWid uintptr, length, elemIndir int, ovfl error) {
+func (dec *Decoder) decodeArrayHelper(state *decoderState, p unsafe.Pointer, elemOp decOp, elemWid uintptr, length, elemIndir int, ovfl error) {
 	instr := &decInstr{elemOp, 0, elemIndir, 0, ovfl}
 	for i := 0; i < length; i++ {
 		if state.b.Len() == 0 {
 			errorf("decoding array or slice: length exceeds input size (%d elements)", length)
 		}
-		up := unsafe.Pointer(p)
+		up := p
 		if elemIndir > 1 {
 			up = decIndirect(up, elemIndir)
 		}
 		elemOp(instr, state, up)
-		p += uintptr(elemWid)
+		p = unsafe.Pointer(uintptr(p) + elemWid)
 	}
 }
 
 // decodeArray decodes an array and stores it through p, that is, p points to the zeroth element.
 // The length is an unsigned integer preceding the elements.  Even though the length is redundant
 // (it's part of the type), it's a useful check and is included in the encoding.
-func (dec *Decoder) decodeArray(atyp reflect.Type, state *decoderState, p uintptr, elemOp decOp, elemWid uintptr, length, indir, elemIndir int, ovfl error) {
+func (dec *Decoder) decodeArray(atyp reflect.Type, state *decoderState, p unsafe.Pointer, elemOp decOp, elemWid uintptr, length, indir, elemIndir int, ovfl error) {
 	if indir > 0 {
 		p = allocate(atyp, p, 1) // All but the last level has been allocated by dec.Indirect
 	}
@@ -591,7 +592,7 @@ func (dec *Decoder) decodeArray(atyp reflect.Type, state *decoderState, p uintpt
 // unlike the other items we can't use a pointer directly.
 func decodeIntoValue(state *decoderState, op decOp, indir int, v reflect.Value, ovfl error) reflect.Value {
 	instr := &decInstr{op, 0, indir, 0, ovfl}
-	up := unsafe.Pointer(unsafeAddr(v))
+	up := unsafeAddr(v)
 	if indir > 1 {
 		up = decIndirect(up, indir)
 	}
@@ -603,7 +604,7 @@ func decodeIntoValue(state *decoderState, op decOp, indir int, v reflect.Value,
 // Maps are encoded as a length followed by key:value pairs.
 // Because the internals of maps are not visible to us, we must
 // use reflection rather than pointer magic.
-func (dec *Decoder) decodeMap(mtyp reflect.Type, state *decoderState, p uintptr, keyOp, elemOp decOp, indir, keyIndir, elemIndir int, ovfl error) {
+func (dec *Decoder) decodeMap(mtyp reflect.Type, state *decoderState, p unsafe.Pointer, keyOp, elemOp decOp, indir, keyIndir, elemIndir int, ovfl error) {
 	if indir > 0 {
 		p = allocate(mtyp, p, 1) // All but the last level has been allocated by dec.Indirect
 	}
@@ -673,7 +674,7 @@ func (dec *Decoder) decodeSlice(atyp reflect.Type, state *decoderState, p uintpt
 		hdrp.Cap = n
 	}
 	hdrp.Len = n
-	dec.decodeArrayHelper(state, hdrp.Data, elemOp, elemWid, n, elemIndir, ovfl)
+	dec.decodeArrayHelper(state, unsafe.Pointer(hdrp.Data), elemOp, elemWid, n, elemIndir, ovfl)
 }
 
 // ignoreSlice skips over the data for a slice value with no destination.
@@ -693,7 +694,7 @@ func setInterfaceValue(ivalue reflect.Value, value reflect.Value) {
 // decodeInterface decodes an interface value and stores it through p.
 // Interfaces are encoded as the name of a concrete type followed by a value.
 // If the name is empty, the value is nil and no value is sent.
-func (dec *Decoder) decodeInterface(ityp reflect.Type, state *decoderState, p uintptr, indir int) {
+func (dec *Decoder) decodeInterface(ityp reflect.Type, state *decoderState, p unsafe.Pointer, indir int) {
 	// Create a writable interface reflect.Value.  We need one even for the nil case.
 	ivalue := allocValue(ityp)
 	// Read the name of the concrete type.
@@ -767,15 +768,22 @@ func (dec *Decoder) ignoreInterface(state *decoderState) {
 
 // decodeGobDecoder decodes something implementing the GobDecoder interface.
 // The data is encoded as a byte slice.
-func (dec *Decoder) decodeGobDecoder(state *decoderState, v reflect.Value) {
+func (dec *Decoder) decodeGobDecoder(ut *userTypeInfo, state *decoderState, v reflect.Value) {
 	// Read the bytes for the value.
 	b := make([]byte, state.decodeUint())
 	_, err := state.b.Read(b)
 	if err != nil {
 		error_(err)
 	}
-	// We know it's a GobDecoder, so just call the method directly.
-	err = v.Interface().(GobDecoder).GobDecode(b)
+	// We know it's one of these.
+	switch ut.externalDec {
+	case xGob:
+		err = v.Interface().(GobDecoder).GobDecode(b)
+	case xBinary:
+		err = v.Interface().(encoding.BinaryUnmarshaler).UnmarshalBinary(b)
+	case xText:
+		err = v.Interface().(encoding.TextUnmarshaler).UnmarshalText(b)
+	}
 	if err != nil {
 		error_(err)
 	}
@@ -825,9 +833,10 @@ var decIgnoreOpMap = map[typeId]decOp{
 func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProgress map[reflect.Type]*decOp) (*decOp, int) {
 	ut := userType(rt)
 	// If the type implements GobEncoder, we handle it without further processing.
-	if ut.isGobDecoder {
+	if ut.externalDec != 0 {
 		return dec.gobDecodeOpFor(ut)
 	}
+
 	// If this type is already in progress, it's a recursive type (e.g. map[string]*T).
 	// Return the pointer to the op we're already building.
 	if opPtr := inProgress[rt]; opPtr != nil {
@@ -850,7 +859,7 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProg
 			elemOp, elemIndir := dec.decOpFor(elemId, t.Elem(), name, inProgress)
 			ovfl := overflow(name)
 			op = func(i *decInstr, state *decoderState, p unsafe.Pointer) {
-				state.dec.decodeArray(t, state, uintptr(p), *elemOp, t.Elem().Size(), t.Len(), i.indir, elemIndir, ovfl)
+				state.dec.decodeArray(t, state, p, *elemOp, t.Elem().Size(), t.Len(), i.indir, elemIndir, ovfl)
 			}
 
 		case reflect.Map:
@@ -860,8 +869,7 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProg
 			elemOp, elemIndir := dec.decOpFor(elemId, t.Elem(), "element of "+name, inProgress)
 			ovfl := overflow(name)
 			op = func(i *decInstr, state *decoderState, p unsafe.Pointer) {
-				up := unsafe.Pointer(p)
-				state.dec.decodeMap(t, state, uintptr(up), *keyOp, *elemOp, i.indir, keyIndir, elemIndir, ovfl)
+				state.dec.decodeMap(t, state, p, *keyOp, *elemOp, i.indir, keyIndir, elemIndir, ovfl)
 			}
 
 		case reflect.Slice:
@@ -890,11 +898,11 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProg
 			}
 			op = func(i *decInstr, state *decoderState, p unsafe.Pointer) {
 				// indirect through enginePtr to delay evaluation for recursive structs.
-				dec.decodeStruct(*enginePtr, userType(typ), uintptr(p), i.indir)
+				dec.decodeStruct(*enginePtr, userType(typ), p, i.indir)
 			}
 		case reflect.Interface:
 			op = func(i *decInstr, state *decoderState, p unsafe.Pointer) {
-				state.dec.decodeInterface(t, state, uintptr(p), i.indir)
+				state.dec.decodeInterface(t, state, p, i.indir)
 			}
 		}
 	}
@@ -955,7 +963,7 @@ func (dec *Decoder) decIgnoreOpFor(wireId typeId) decOp {
 				state.dec.ignoreStruct(*enginePtr)
 			}
 
-		case wire.GobEncoderT != nil:
+		case wire.GobEncoderT != nil, wire.BinaryMarshalerT != nil, wire.TextMarshalerT != nil:
 			op = func(i *decInstr, state *decoderState, p unsafe.Pointer) {
 				state.dec.ignoreGobDecoder(state)
 			}
@@ -994,7 +1002,7 @@ func (dec *Decoder) gobDecodeOpFor(ut *userTypeInfo) (*decOp, int) {
 		} else {
 			v = reflect.NewAt(rcvrType, p).Elem()
 		}
-		state.dec.decodeGobDecoder(state, v)
+		state.dec.decodeGobDecoder(ut, state, v)
 	}
 	return &op, int(ut.indir)
 
@@ -1011,12 +1019,18 @@ func (dec *Decoder) compatibleType(fr reflect.Type, fw typeId, inProgress map[re
 	inProgress[fr] = fw
 	ut := userType(fr)
 	wire, ok := dec.wireType[fw]
-	// If fr is a GobDecoder, the wire type must be GobEncoder.
-	// And if fr is not a GobDecoder, the wire type must not be either.
-	if ut.isGobDecoder != (ok && wire.GobEncoderT != nil) { // the parentheses look odd but are correct.
+	// If wire was encoded with an encoding method, fr must have that method.
+	// And if not, it must not.
+	// At most one of the booleans in ut is set.
+	// We could possibly relax this constraint in the future in order to
+	// choose the decoding method using the data in the wireType.
+	// The parentheses look odd but are correct.
+	if (ut.externalDec == xGob) != (ok && wire.GobEncoderT != nil) ||
+		(ut.externalDec == xBinary) != (ok && wire.BinaryMarshalerT != nil) ||
+		(ut.externalDec == xText) != (ok && wire.TextMarshalerT != nil) {
 		return false
 	}
-	if ut.isGobDecoder { // This test trumps all others.
+	if ut.externalDec != 0 { // This test trumps all others.
 		return true
 	}
 	switch t := ut.base; t.Kind() {
@@ -1115,8 +1129,7 @@ func (dec *Decoder) compileIgnoreSingle(remoteId typeId) (engine *decEngine, err
 func (dec *Decoder) compileDec(remoteId typeId, ut *userTypeInfo) (engine *decEngine, err error) {
 	rt := ut.base
 	srt := rt
-	if srt.Kind() != reflect.Struct ||
-		ut.isGobDecoder {
+	if srt.Kind() != reflect.Struct || ut.externalDec != 0 {
 		return dec.compileSingle(remoteId, ut)
 	}
 	var wireStruct *structType
@@ -1224,14 +1237,14 @@ func (dec *Decoder) decodeValue(wireId typeId, val reflect.Value) {
 		return
 	}
 	engine := *enginePtr
-	if st := base; st.Kind() == reflect.Struct && !ut.isGobDecoder {
+	if st := base; st.Kind() == reflect.Struct && ut.externalDec == 0 {
 		if engine.numInstr == 0 && st.NumField() > 0 && len(dec.wireType[wireId].StructT.Field) > 0 {
 			name := base.Name()
 			errorf("type mismatch: no fields matched compiling decoder for %s", name)
 		}
-		dec.decodeStruct(engine, ut, uintptr(unsafeAddr(val)), ut.indir)
+		dec.decodeStruct(engine, ut, unsafeAddr(val), ut.indir)
 	} else {
-		dec.decodeSingle(engine, ut, uintptr(unsafeAddr(val)))
+		dec.decodeSingle(engine, ut, unsafeAddr(val))
 	}
 }
 
@@ -1283,13 +1296,13 @@ func init() {
 // into existing structs or slices cannot be addressed,
 // so simulate it by returning a pointer to a copy.
 // Each call allocates once.
-func unsafeAddr(v reflect.Value) uintptr {
+func unsafeAddr(v reflect.Value) unsafe.Pointer {
 	if v.CanAddr() {
-		return v.UnsafeAddr()
+		return unsafe.Pointer(v.UnsafeAddr())
 	}
 	x := reflect.New(v.Type()).Elem()
 	x.Set(v)
-	return x.UnsafeAddr()
+	return unsafe.Pointer(x.UnsafeAddr())
 }
 
 // Gob depends on being able to take the address
diff --git a/libgo/go/encoding/gob/doc.go b/libgo/go/encoding/gob/doc.go
index 5bd61b1..28f0c05 100644
--- a/libgo/go/encoding/gob/doc.go
+++ b/libgo/go/encoding/gob/doc.go
@@ -8,6 +8,12 @@ Encoder (transmitter) and a Decoder (receiver).  A typical use is transporting
 arguments and results of remote procedure calls (RPCs) such as those provided by
 package "rpc".
 
+The implementation compiles a custom codec for each data type in the stream and
+is most efficient when a single Encoder is used to transmit a stream of values,
+amortizing the cost of compilation.
+
+Basics
+
 A stream of gobs is self-describing.  Each data item in the stream is preceded by
 a specification of its type, expressed in terms of a small set of predefined
 types.  Pointers are not transmitted, but the things they point to are
@@ -20,6 +26,8 @@ all type information is sent before it is needed.  At the receive side, a
 Decoder retrieves values from the encoded stream and unpacks them into local
 variables.
 
+Types and Values
+
 The source and destination values/types need not correspond exactly.  For structs,
 fields (identified by name) that are in the source but absent from the receiving
 variable will be ignored.  Fields that are in the receiving variable but missing
@@ -67,19 +75,29 @@ point values may be received into any floating point variable.  However,
 the destination variable must be able to represent the value or the decode
 operation will fail.
 
-Structs, arrays and slices are also supported.  Structs encode and
-decode only exported fields. Strings and arrays of bytes are supported
-with a special, efficient representation (see below).  When a slice
-is decoded, if the existing slice has capacity the slice will be
-extended in place; if not, a new array is allocated.  Regardless,
-the length of the resulting slice reports the number of elements
-decoded.
+Structs, arrays and slices are also supported. Structs encode and decode only
+exported fields. Strings and arrays of bytes are supported with a special,
+efficient representation (see below). When a slice is decoded, if the existing
+slice has capacity the slice will be extended in place; if not, a new array is
+allocated. Regardless, the length of the resulting slice reports the number of
+elements decoded.
+
+Functions and channels will not be sent in a gob. Attempting to encode such a value
+at top the level will fail. A struct field of chan or func type is treated exactly
+like an unexported field and is ignored.
+
+Gob can encode a value of any type implementing the GobEncoder,
+encoding.BinaryMarshaler, or encoding.TextMarshaler interfaces by calling the
+corresponding method, in that order of preference.
+
+Gob can decode a value of any type implementing the GobDecoder,
+encoding.BinaryUnmarshaler, or encoding.TextUnmarshaler interfaces by calling
+the corresponding method, again in that order of preference.
 
-Functions and channels cannot be sent in a gob.  Attempting
-to encode a value that contains one will fail.
+Encoding Details
 
-The rest of this comment documents the encoding, details that are not important
-for most users.  Details are presented bottom-up.
+This section documents the encoding, details that are not important for most
+users. Details are presented bottom-up.
 
 An unsigned integer is sent one of two ways.  If it is less than 128, it is sent
 as a byte with that value.  Otherwise it is sent as a minimal-length big-endian
diff --git a/libgo/go/encoding/gob/encode.go b/libgo/go/encoding/gob/encode.go
index ea37a6c..d158b64 100644
--- a/libgo/go/encoding/gob/encode.go
+++ b/libgo/go/encoding/gob/encode.go
@@ -6,6 +6,7 @@ package gob
 
 import (
 	"bytes"
+	"encoding"
 	"math"
 	"reflect"
 	"unsafe"
@@ -338,14 +339,14 @@ type encEngine struct {
 const singletonField = 0
 
 // encodeSingle encodes a single top-level non-struct value.
-func (enc *Encoder) encodeSingle(b *bytes.Buffer, engine *encEngine, basep uintptr) {
+func (enc *Encoder) encodeSingle(b *bytes.Buffer, engine *encEngine, basep unsafe.Pointer) {
 	state := enc.newEncoderState(b)
 	state.fieldnum = singletonField
 	// There is no surrounding struct to frame the transmission, so we must
 	// generate data even if the item is zero.  To do this, set sendZero.
 	state.sendZero = true
 	instr := &engine.instr[singletonField]
-	p := unsafe.Pointer(basep) // offset will be zero
+	p := basep // offset will be zero
 	if instr.indir > 0 {
 		if p = encIndirect(p, instr.indir); p == nil {
 			return
@@ -356,12 +357,12 @@ func (enc *Encoder) encodeSingle(b *bytes.Buffer, engine *encEngine, basep uintp
 }
 
 // encodeStruct encodes a single struct value.
-func (enc *Encoder) encodeStruct(b *bytes.Buffer, engine *encEngine, basep uintptr) {
+func (enc *Encoder) encodeStruct(b *bytes.Buffer, engine *encEngine, basep unsafe.Pointer) {
 	state := enc.newEncoderState(b)
 	state.fieldnum = -1
 	for i := 0; i < len(engine.instr); i++ {
 		instr := &engine.instr[i]
-		p := unsafe.Pointer(basep + instr.offset)
+		p := unsafe.Pointer(uintptr(basep) + instr.offset)
 		if instr.indir > 0 {
 			if p = encIndirect(p, instr.indir); p == nil {
 				continue
@@ -373,22 +374,22 @@ func (enc *Encoder) encodeStruct(b *bytes.Buffer, engine *encEngine, basep uintp
 }
 
 // encodeArray encodes the array whose 0th element is at p.
-func (enc *Encoder) encodeArray(b *bytes.Buffer, p uintptr, op encOp, elemWid uintptr, elemIndir int, length int) {
+func (enc *Encoder) encodeArray(b *bytes.Buffer, p unsafe.Pointer, op encOp, elemWid uintptr, elemIndir int, length int) {
 	state := enc.newEncoderState(b)
 	state.fieldnum = -1
 	state.sendZero = true
 	state.encodeUint(uint64(length))
 	for i := 0; i < length; i++ {
 		elemp := p
-		up := unsafe.Pointer(elemp)
 		if elemIndir > 0 {
-			if up = encIndirect(up, elemIndir); up == nil {
+			up := encIndirect(elemp, elemIndir)
+			if up == nil {
 				errorf("encodeArray: nil element")
 			}
-			elemp = uintptr(up)
+			elemp = up
 		}
-		op(nil, state, unsafe.Pointer(elemp))
-		p += uintptr(elemWid)
+		op(nil, state, elemp)
+		p = unsafe.Pointer(uintptr(p) + elemWid)
 	}
 	enc.freeEncoderState(state)
 }
@@ -401,7 +402,7 @@ func encodeReflectValue(state *encoderState, v reflect.Value, op encOp, indir in
 	if !v.IsValid() {
 		errorf("encodeReflectValue: nil element")
 	}
-	op(nil, state, unsafe.Pointer(unsafeAddr(v)))
+	op(nil, state, unsafeAddr(v))
 }
 
 // encodeMap encodes a map as unsigned count followed by key:value pairs.
@@ -474,7 +475,7 @@ func (enc *Encoder) encodeInterface(b *bytes.Buffer, iv reflect.Value) {
 	enc.freeEncoderState(state)
 }
 
-// isZero returns whether the value is the zero of its type.
+// isZero reports whether the value is the zero of its type.
 func isZero(val reflect.Value) bool {
 	switch val.Kind() {
 	case reflect.Array:
@@ -511,10 +512,20 @@ func isZero(val reflect.Value) bool {
 
 // encGobEncoder encodes a value that implements the GobEncoder interface.
 // The data is sent as a byte array.
-func (enc *Encoder) encodeGobEncoder(b *bytes.Buffer, v reflect.Value) {
+func (enc *Encoder) encodeGobEncoder(b *bytes.Buffer, ut *userTypeInfo, v reflect.Value) {
 	// TODO: should we catch panics from the called method?
-	// We know it's a GobEncoder, so just call the method directly.
-	data, err := v.Interface().(GobEncoder).GobEncode()
+
+	var data []byte
+	var err error
+	// We know it's one of these.
+	switch ut.externalEnc {
+	case xGob:
+		data, err = v.Interface().(GobEncoder).GobEncode()
+	case xBinary:
+		data, err = v.Interface().(encoding.BinaryMarshaler).MarshalBinary()
+	case xText:
+		data, err = v.Interface().(encoding.TextMarshaler).MarshalText()
+	}
 	if err != nil {
 		error_(err)
 	}
@@ -550,7 +561,7 @@ var encOpTable = [...]encOp{
 func (enc *Encoder) encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp) (*encOp, int) {
 	ut := userType(rt)
 	// If the type implements GobEncoder, we handle it without further processing.
-	if ut.isGobEncoder {
+	if ut.externalEnc != 0 {
 		return enc.gobEncodeOpFor(ut)
 	}
 	// If this type is already in progress, it's a recursive type (e.g. map[string]*T).
@@ -575,21 +586,21 @@ func (enc *Encoder) encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp
 				break
 			}
 			// Slices have a header; we decode it to find the underlying array.
-			elemOp, indir := enc.encOpFor(t.Elem(), inProgress)
+			elemOp, elemIndir := enc.encOpFor(t.Elem(), inProgress)
 			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
 				slice := (*reflect.SliceHeader)(p)
 				if !state.sendZero && slice.Len == 0 {
 					return
 				}
 				state.update(i)
-				state.enc.encodeArray(state.b, slice.Data, *elemOp, t.Elem().Size(), indir, int(slice.Len))
+				state.enc.encodeArray(state.b, unsafe.Pointer(slice.Data), *elemOp, t.Elem().Size(), elemIndir, int(slice.Len))
 			}
 		case reflect.Array:
 			// True arrays have size in the type.
-			elemOp, indir := enc.encOpFor(t.Elem(), inProgress)
+			elemOp, elemIndir := enc.encOpFor(t.Elem(), inProgress)
 			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
 				state.update(i)
-				state.enc.encodeArray(state.b, uintptr(p), *elemOp, t.Elem().Size(), indir, t.Len())
+				state.enc.encodeArray(state.b, p, *elemOp, t.Elem().Size(), elemIndir, t.Len())
 			}
 		case reflect.Map:
 			keyOp, keyIndir := enc.encOpFor(t.Key(), inProgress)
@@ -615,7 +626,7 @@ func (enc *Encoder) encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp
 			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
 				state.update(i)
 				// indirect through info to delay evaluation for recursive structs
-				state.enc.encodeStruct(state.b, info.encoder, uintptr(p))
+				state.enc.encodeStruct(state.b, info.encoder, p)
 			}
 		case reflect.Interface:
 			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
@@ -661,7 +672,7 @@ func (enc *Encoder) gobEncodeOpFor(ut *userTypeInfo) (*encOp, int) {
 			return
 		}
 		state.update(i)
-		state.enc.encodeGobEncoder(state.b, v)
+		state.enc.encodeGobEncoder(state.b, ut, v)
 	}
 	return &op, int(ut.encIndir) // encIndir: op will get called with p == address of receiver.
 }
@@ -672,14 +683,13 @@ func (enc *Encoder) compileEnc(ut *userTypeInfo) *encEngine {
 	engine := new(encEngine)
 	seen := make(map[reflect.Type]*encOp)
 	rt := ut.base
-	if ut.isGobEncoder {
+	if ut.externalEnc != 0 {
 		rt = ut.user
 	}
-	if !ut.isGobEncoder &&
-		srt.Kind() == reflect.Struct {
+	if ut.externalEnc == 0 && srt.Kind() == reflect.Struct {
 		for fieldNum, wireFieldNum := 0, 0; fieldNum < srt.NumField(); fieldNum++ {
 			f := srt.Field(fieldNum)
-			if !isExported(f.Name) {
+			if !isSent(&f) {
 				continue
 			}
 			op, indir := enc.encOpFor(f.Type, seen)
@@ -736,13 +746,13 @@ func (enc *Encoder) encode(b *bytes.Buffer, value reflect.Value, ut *userTypeInf
 	defer catchError(&enc.err)
 	engine := enc.lockAndGetEncEngine(ut)
 	indir := ut.indir
-	if ut.isGobEncoder {
+	if ut.externalEnc != 0 {
 		indir = int(ut.encIndir)
 	}
 	for i := 0; i < indir; i++ {
 		value = reflect.Indirect(value)
 	}
-	if !ut.isGobEncoder && value.Type().Kind() == reflect.Struct {
+	if ut.externalEnc == 0 && value.Type().Kind() == reflect.Struct {
 		enc.encodeStruct(b, engine, unsafeAddr(value))
 	} else {
 		enc.encodeSingle(b, engine, unsafeAddr(value))
diff --git a/libgo/go/encoding/gob/encoder.go b/libgo/go/encoding/gob/encoder.go
index f669c3d..a3301c3 100644
--- a/libgo/go/encoding/gob/encoder.go
+++ b/libgo/go/encoding/gob/encoder.go
@@ -6,7 +6,6 @@ package gob
 
 import (
 	"bytes"
-	"errors"
 	"io"
 	"reflect"
 	"sync"
@@ -54,10 +53,6 @@ func (enc *Encoder) popWriter() {
 	enc.w = enc.w[0 : len(enc.w)-1]
 }
 
-func (enc *Encoder) badType(rt reflect.Type) {
-	enc.setError(errors.New("gob: can't encode type " + rt.String()))
-}
-
 func (enc *Encoder) setError(err error) {
 	if enc.err == nil { // remember the first.
 		enc.err = err
@@ -135,7 +130,7 @@ func (enc *Encoder) sendActualType(w io.Writer, state *encoderState, ut *userTyp
 // sendType sends the type info to the other side, if necessary.
 func (enc *Encoder) sendType(w io.Writer, state *encoderState, origt reflect.Type) (sent bool) {
 	ut := userType(origt)
-	if ut.isGobEncoder {
+	if ut.externalEnc != 0 {
 		// The rules are different: regardless of the underlying type's representation,
 		// we need to tell the other side that the base type is a GobEncoder.
 		return enc.sendActualType(w, state, ut, ut.base)
@@ -163,8 +158,7 @@ func (enc *Encoder) sendType(w io.Writer, state *encoderState, origt reflect.Typ
 		// structs must be sent so we know their fields.
 		break
 	case reflect.Chan, reflect.Func:
-		// Probably a bad field in a struct.
-		enc.badType(rt)
+		// If we get here, it's a field of a struct; ignore it.
 		return
 	}
 
@@ -184,7 +178,7 @@ func (enc *Encoder) sendTypeDescriptor(w io.Writer, state *encoderState, ut *use
 	// Make sure the type is known to the other side.
 	// First, have we already sent this type?
 	rt := ut.base
-	if ut.isGobEncoder {
+	if ut.externalEnc != 0 {
 		rt = ut.user
 	}
 	if _, alreadySent := enc.sent[rt]; !alreadySent {
diff --git a/libgo/go/encoding/gob/encoder_test.go b/libgo/go/encoding/gob/encoder_test.go
index b684772c..4ecf51d 100644
--- a/libgo/go/encoding/gob/encoder_test.go
+++ b/libgo/go/encoding/gob/encoder_test.go
@@ -131,7 +131,7 @@ func TestBadData(t *testing.T) {
 	corruptDataCheck("\x03now is the time for all good men", errBadType, t)
 }
 
-// Types not supported by the Encoder.
+// Types not supported at top level by the Encoder.
 var unsupportedValues = []interface{}{
 	make(chan int),
 	func(a int) bool { return true },
@@ -662,19 +662,35 @@ func TestSequentialDecoder(t *testing.T) {
 	}
 }
 
-// Should be able to have unrepresentable fields (chan, func) as long as they
-// are unexported.
+// Should be able to have unrepresentable fields (chan, func, *chan etc.); we just ignore them.
 type Bug2 struct {
-	A int
-	b chan int
-}
-
-func TestUnexportedChan(t *testing.T) {
-	b := Bug2{23, make(chan int)}
-	var stream bytes.Buffer
-	enc := NewEncoder(&stream)
-	if err := enc.Encode(b); err != nil {
-		t.Fatalf("error encoding unexported channel: %s", err)
+	A   int
+	C   chan int
+	CP  *chan int
+	F   func()
+	FPP **func()
+}
+
+func TestChanFuncIgnored(t *testing.T) {
+	c := make(chan int)
+	f := func() {}
+	fp := &f
+	b0 := Bug2{23, c, &c, f, &fp}
+	var buf bytes.Buffer
+	enc := NewEncoder(&buf)
+	if err := enc.Encode(b0); err != nil {
+		t.Fatal("error encoding:", err)
+	}
+	var b1 Bug2
+	err := NewDecoder(&buf).Decode(&b1)
+	if err != nil {
+		t.Fatal("decode:", err)
+	}
+	if b1.A != b0.A {
+		t.Fatalf("got %d want %d", b1.A, b0.A)
+	}
+	if b1.C != nil || b1.CP != nil || b1.F != nil || b1.FPP != nil {
+		t.Fatal("unexpected value for chan or func")
 	}
 }
 
diff --git a/libgo/go/encoding/gob/gobencdec_test.go b/libgo/go/encoding/gob/gobencdec_test.go
index ddcd80b..301551d 100644
--- a/libgo/go/encoding/gob/gobencdec_test.go
+++ b/libgo/go/encoding/gob/gobencdec_test.go
@@ -34,6 +34,14 @@ type Gobber int
 
 type ValueGobber string // encodes with a value, decodes with a pointer.
 
+type BinaryGobber int
+
+type BinaryValueGobber string
+
+type TextGobber int
+
+type TextValueGobber string
+
 // The relevant methods
 
 func (g *ByteStruct) GobEncode() ([]byte, error) {
@@ -101,6 +109,24 @@ func (g *Gobber) GobDecode(data []byte) error {
 	return err
 }
 
+func (g *BinaryGobber) MarshalBinary() ([]byte, error) {
+	return []byte(fmt.Sprintf("VALUE=%d", *g)), nil
+}
+
+func (g *BinaryGobber) UnmarshalBinary(data []byte) error {
+	_, err := fmt.Sscanf(string(data), "VALUE=%d", (*int)(g))
+	return err
+}
+
+func (g *TextGobber) MarshalText() ([]byte, error) {
+	return []byte(fmt.Sprintf("VALUE=%d", *g)), nil
+}
+
+func (g *TextGobber) UnmarshalText(data []byte) error {
+	_, err := fmt.Sscanf(string(data), "VALUE=%d", (*int)(g))
+	return err
+}
+
 func (v ValueGobber) GobEncode() ([]byte, error) {
 	return []byte(fmt.Sprintf("VALUE=%s", v)), nil
 }
@@ -110,6 +136,24 @@ func (v *ValueGobber) GobDecode(data []byte) error {
 	return err
 }
 
+func (v BinaryValueGobber) MarshalBinary() ([]byte, error) {
+	return []byte(fmt.Sprintf("VALUE=%s", v)), nil
+}
+
+func (v *BinaryValueGobber) UnmarshalBinary(data []byte) error {
+	_, err := fmt.Sscanf(string(data), "VALUE=%s", (*string)(v))
+	return err
+}
+
+func (v TextValueGobber) MarshalText() ([]byte, error) {
+	return []byte(fmt.Sprintf("VALUE=%s", v)), nil
+}
+
+func (v *TextValueGobber) UnmarshalText(data []byte) error {
+	_, err := fmt.Sscanf(string(data), "VALUE=%s", (*string)(v))
+	return err
+}
+
 // Structs that include GobEncodable fields.
 
 type GobTest0 struct {
@@ -130,28 +174,42 @@ type GobTest2 struct {
 type GobTest3 struct {
 	X int // guarantee we have  something in common with GobTest*
 	G *Gobber
+	B *BinaryGobber
+	T *TextGobber
 }
 
 type GobTest4 struct {
-	X int // guarantee we have  something in common with GobTest*
-	V ValueGobber
+	X  int // guarantee we have  something in common with GobTest*
+	V  ValueGobber
+	BV BinaryValueGobber
+	TV TextValueGobber
 }
 
 type GobTest5 struct {
-	X int // guarantee we have  something in common with GobTest*
-	V *ValueGobber
+	X  int // guarantee we have  something in common with GobTest*
+	V  *ValueGobber
+	BV *BinaryValueGobber
+	TV *TextValueGobber
 }
 
 type GobTest6 struct {
-	X int // guarantee we have  something in common with GobTest*
-	V ValueGobber
-	W *ValueGobber
+	X  int // guarantee we have  something in common with GobTest*
+	V  ValueGobber
+	W  *ValueGobber
+	BV BinaryValueGobber
+	BW *BinaryValueGobber
+	TV TextValueGobber
+	TW *TextValueGobber
 }
 
 type GobTest7 struct {
-	X int // guarantee we have  something in common with GobTest*
-	V *ValueGobber
-	W ValueGobber
+	X  int // guarantee we have  something in common with GobTest*
+	V  *ValueGobber
+	W  ValueGobber
+	BV *BinaryValueGobber
+	BW BinaryValueGobber
+	TV *TextValueGobber
+	TW TextValueGobber
 }
 
 type GobTestIgnoreEncoder struct {
@@ -198,7 +256,9 @@ func TestGobEncoderField(t *testing.T) {
 	// Now a field that's not a structure.
 	b.Reset()
 	gobber := Gobber(23)
-	err = enc.Encode(GobTest3{17, &gobber})
+	bgobber := BinaryGobber(24)
+	tgobber := TextGobber(25)
+	err = enc.Encode(GobTest3{17, &gobber, &bgobber, &tgobber})
 	if err != nil {
 		t.Fatal("encode error:", err)
 	}
@@ -207,7 +267,7 @@ func TestGobEncoderField(t *testing.T) {
 	if err != nil {
 		t.Fatal("decode error:", err)
 	}
-	if *y.G != 23 {
+	if *y.G != 23 || *y.B != 24 || *y.T != 25 {
 		t.Errorf("expected '23 got %d", *y.G)
 	}
 }
@@ -357,7 +417,7 @@ func TestGobEncoderValueEncoder(t *testing.T) {
 	// first, string in field to byte in field
 	b := new(bytes.Buffer)
 	enc := NewEncoder(b)
-	err := enc.Encode(GobTest4{17, ValueGobber("hello")})
+	err := enc.Encode(GobTest4{17, ValueGobber("hello"), BinaryValueGobber("Καλημέρα"), TextValueGobber("こんにちは")})
 	if err != nil {
 		t.Fatal("encode error:", err)
 	}
@@ -367,8 +427,8 @@ func TestGobEncoderValueEncoder(t *testing.T) {
 	if err != nil {
 		t.Fatal("decode error:", err)
 	}
-	if *x.V != "hello" {
-		t.Errorf("expected `hello` got %s", x.V)
+	if *x.V != "hello" || *x.BV != "Καλημέρα" || *x.TV != "こんにちは" {
+		t.Errorf("expected `hello` got %s", *x.V)
 	}
 }
 
@@ -377,13 +437,17 @@ func TestGobEncoderValueEncoder(t *testing.T) {
 func TestGobEncoderValueThenPointer(t *testing.T) {
 	v := ValueGobber("forty-two")
 	w := ValueGobber("six-by-nine")
+	bv := BinaryValueGobber("1nanocentury")
+	bw := BinaryValueGobber("πseconds")
+	tv := TextValueGobber("gravitationalacceleration")
+	tw := TextValueGobber("π²ft/s²")
 
 	// this was a bug: encoding a GobEncoder by value before a GobEncoder
 	// pointer would cause duplicate type definitions to be sent.
 
 	b := new(bytes.Buffer)
 	enc := NewEncoder(b)
-	if err := enc.Encode(GobTest6{42, v, &w}); err != nil {
+	if err := enc.Encode(GobTest6{42, v, &w, bv, &bw, tv, &tw}); err != nil {
 		t.Fatal("encode error:", err)
 	}
 	dec := NewDecoder(b)
@@ -391,6 +455,7 @@ func TestGobEncoderValueThenPointer(t *testing.T) {
 	if err := dec.Decode(x); err != nil {
 		t.Fatal("decode error:", err)
 	}
+
 	if got, want := x.V, v; got != want {
 		t.Errorf("v = %q, want %q", got, want)
 	}
@@ -399,6 +464,24 @@ func TestGobEncoderValueThenPointer(t *testing.T) {
 	} else if *got != want {
 		t.Errorf("w = %q, want %q", *got, want)
 	}
+
+	if got, want := x.BV, bv; got != want {
+		t.Errorf("bv = %q, want %q", got, want)
+	}
+	if got, want := x.BW, bw; got == nil {
+		t.Errorf("bw = nil, want %q", want)
+	} else if *got != want {
+		t.Errorf("bw = %q, want %q", *got, want)
+	}
+
+	if got, want := x.TV, tv; got != want {
+		t.Errorf("tv = %q, want %q", got, want)
+	}
+	if got, want := x.TW, tw; got == nil {
+		t.Errorf("tw = nil, want %q", want)
+	} else if *got != want {
+		t.Errorf("tw = %q, want %q", *got, want)
+	}
 }
 
 // Test that we can use a pointer then a value type of a GobEncoder
@@ -406,10 +489,14 @@ func TestGobEncoderValueThenPointer(t *testing.T) {
 func TestGobEncoderPointerThenValue(t *testing.T) {
 	v := ValueGobber("forty-two")
 	w := ValueGobber("six-by-nine")
+	bv := BinaryValueGobber("1nanocentury")
+	bw := BinaryValueGobber("πseconds")
+	tv := TextValueGobber("gravitationalacceleration")
+	tw := TextValueGobber("π²ft/s²")
 
 	b := new(bytes.Buffer)
 	enc := NewEncoder(b)
-	if err := enc.Encode(GobTest7{42, &v, w}); err != nil {
+	if err := enc.Encode(GobTest7{42, &v, w, &bv, bw, &tv, tw}); err != nil {
 		t.Fatal("encode error:", err)
 	}
 	dec := NewDecoder(b)
@@ -417,14 +504,33 @@ func TestGobEncoderPointerThenValue(t *testing.T) {
 	if err := dec.Decode(x); err != nil {
 		t.Fatal("decode error:", err)
 	}
+
 	if got, want := x.V, v; got == nil {
 		t.Errorf("v = nil, want %q", want)
 	} else if *got != want {
-		t.Errorf("v = %q, want %q", got, want)
+		t.Errorf("v = %q, want %q", *got, want)
 	}
 	if got, want := x.W, w; got != want {
 		t.Errorf("w = %q, want %q", got, want)
 	}
+
+	if got, want := x.BV, bv; got == nil {
+		t.Errorf("bv = nil, want %q", want)
+	} else if *got != want {
+		t.Errorf("bv = %q, want %q", *got, want)
+	}
+	if got, want := x.BW, bw; got != want {
+		t.Errorf("bw = %q, want %q", got, want)
+	}
+
+	if got, want := x.TV, tv; got == nil {
+		t.Errorf("tv = nil, want %q", want)
+	} else if *got != want {
+		t.Errorf("tv = %q, want %q", *got, want)
+	}
+	if got, want := x.TW, tw; got != want {
+		t.Errorf("tw = %q, want %q", got, want)
+	}
 }
 
 func TestGobEncoderFieldTypeError(t *testing.T) {
@@ -521,7 +627,9 @@ func TestGobEncoderIgnoreNonStructField(t *testing.T) {
 	// First a field that's a structure.
 	enc := NewEncoder(b)
 	gobber := Gobber(23)
-	err := enc.Encode(GobTest3{17, &gobber})
+	bgobber := BinaryGobber(24)
+	tgobber := TextGobber(25)
+	err := enc.Encode(GobTest3{17, &gobber, &bgobber, &tgobber})
 	if err != nil {
 		t.Fatal("encode error:", err)
 	}
diff --git a/libgo/go/encoding/gob/timing_test.go b/libgo/go/encoding/gob/timing_test.go
index f589675..9fbb0ac 100644
--- a/libgo/go/encoding/gob/timing_test.go
+++ b/libgo/go/encoding/gob/timing_test.go
@@ -6,7 +6,6 @@ package gob
 
 import (
 	"bytes"
-	"fmt"
 	"io"
 	"os"
 	"runtime"
@@ -50,6 +49,9 @@ func BenchmarkEndToEndByteBuffer(b *testing.B) {
 }
 
 func TestCountEncodeMallocs(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping malloc count in short mode")
+	}
 	if runtime.GOMAXPROCS(0) > 1 {
 		t.Skip("skipping; GOMAXPROCS>1")
 	}
@@ -66,10 +68,15 @@ func TestCountEncodeMallocs(t *testing.T) {
 			t.Fatal("encode:", err)
 		}
 	})
-	fmt.Printf("mallocs per encode of type Bench: %v\n", allocs)
+	if allocs != 0 {
+		t.Fatalf("mallocs per encode of type Bench: %v; wanted 0\n", allocs)
+	}
 }
 
 func TestCountDecodeMallocs(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping malloc count in short mode")
+	}
 	if runtime.GOMAXPROCS(0) > 1 {
 		t.Skip("skipping; GOMAXPROCS>1")
 	}
@@ -96,5 +103,7 @@ func TestCountDecodeMallocs(t *testing.T) {
 			t.Fatal("decode:", err)
 		}
 	})
-	fmt.Printf("mallocs per decode of type Bench: %v\n", allocs)
+	if allocs != 3 {
+		t.Fatalf("mallocs per decode of type Bench: %v; wanted 3\n", allocs)
+	}
 }
diff --git a/libgo/go/encoding/gob/type.go b/libgo/go/encoding/gob/type.go
index 7fa0b499..65bf17b 100644
--- a/libgo/go/encoding/gob/type.go
+++ b/libgo/go/encoding/gob/type.go
@@ -5,6 +5,7 @@
 package gob
 
 import (
+	"encoding"
 	"errors"
 	"fmt"
 	"os"
@@ -18,14 +19,21 @@ import (
 // to the package.  It's computed once and stored in a map keyed by reflection
 // type.
 type userTypeInfo struct {
-	user         reflect.Type // the type the user handed us
-	base         reflect.Type // the base type after all indirections
-	indir        int          // number of indirections to reach the base type
-	isGobEncoder bool         // does the type implement GobEncoder?
-	isGobDecoder bool         // does the type implement GobDecoder?
-	encIndir     int8         // number of indirections to reach the receiver type; may be negative
-	decIndir     int8         // number of indirections to reach the receiver type; may be negative
-}
+	user        reflect.Type // the type the user handed us
+	base        reflect.Type // the base type after all indirections
+	indir       int          // number of indirections to reach the base type
+	externalEnc int          // xGob, xBinary, or xText
+	externalDec int          // xGob, xBinary or xText
+	encIndir    int8         // number of indirections to reach the receiver type; may be negative
+	decIndir    int8         // number of indirections to reach the receiver type; may be negative
+}
+
+// externalEncoding bits
+const (
+	xGob    = 1 + iota // GobEncoder or GobDecoder
+	xBinary            // encoding.BinaryMarshaler or encoding.BinaryUnmarshaler
+	xText              // encoding.TextMarshaler or encoding.TextUnmarshaler
+)
 
 var (
 	// Protected by an RWMutex because we read it a lot and write
@@ -75,15 +83,34 @@ func validUserType(rt reflect.Type) (ut *userTypeInfo, err error) {
 		}
 		ut.indir++
 	}
-	ut.isGobEncoder, ut.encIndir = implementsInterface(ut.user, gobEncoderInterfaceType)
-	ut.isGobDecoder, ut.decIndir = implementsInterface(ut.user, gobDecoderInterfaceType)
+
+	if ok, indir := implementsInterface(ut.user, gobEncoderInterfaceType); ok {
+		ut.externalEnc, ut.encIndir = xGob, indir
+	} else if ok, indir := implementsInterface(ut.user, binaryMarshalerInterfaceType); ok {
+		ut.externalEnc, ut.encIndir = xBinary, indir
+	} else if ok, indir := implementsInterface(ut.user, textMarshalerInterfaceType); ok {
+		ut.externalEnc, ut.encIndir = xText, indir
+	}
+
+	if ok, indir := implementsInterface(ut.user, gobDecoderInterfaceType); ok {
+		ut.externalDec, ut.decIndir = xGob, indir
+	} else if ok, indir := implementsInterface(ut.user, binaryUnmarshalerInterfaceType); ok {
+		ut.externalDec, ut.decIndir = xBinary, indir
+	} else if ok, indir := implementsInterface(ut.user, textUnmarshalerInterfaceType); ok {
+		ut.externalDec, ut.decIndir = xText, indir
+	}
+
 	userTypeCache[rt] = ut
 	return
 }
 
 var (
-	gobEncoderInterfaceType = reflect.TypeOf((*GobEncoder)(nil)).Elem()
-	gobDecoderInterfaceType = reflect.TypeOf((*GobDecoder)(nil)).Elem()
+	gobEncoderInterfaceType        = reflect.TypeOf((*GobEncoder)(nil)).Elem()
+	gobDecoderInterfaceType        = reflect.TypeOf((*GobDecoder)(nil)).Elem()
+	binaryMarshalerInterfaceType   = reflect.TypeOf((*encoding.BinaryMarshaler)(nil)).Elem()
+	binaryUnmarshalerInterfaceType = reflect.TypeOf((*encoding.BinaryUnmarshaler)(nil)).Elem()
+	textMarshalerInterfaceType     = reflect.TypeOf((*encoding.TextMarshaler)(nil)).Elem()
+	textUnmarshalerInterfaceType   = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
 )
 
 // implementsInterface reports whether the type implements the
@@ -412,7 +439,7 @@ func newStructType(name string) *structType {
 // works through typeIds and userTypeInfos alone.
 func newTypeObject(name string, ut *userTypeInfo, rt reflect.Type) (gobType, error) {
 	// Does this type implement GobEncoder?
-	if ut.isGobEncoder {
+	if ut.externalEnc != 0 {
 		return newGobEncoderType(name), nil
 	}
 	var err error
@@ -499,7 +526,7 @@ func newTypeObject(name string, ut *userTypeInfo, rt reflect.Type) (gobType, err
 		idToType[st.id()] = st
 		for i := 0; i < t.NumField(); i++ {
 			f := t.Field(i)
-			if !isExported(f.Name) {
+			if !isSent(&f) {
 				continue
 			}
 			typ := userType(f.Type).base
@@ -534,6 +561,25 @@ func isExported(name string) bool {
 	return unicode.IsUpper(rune)
 }
 
+// isSent reports whether this struct field is to be transmitted.
+// It will be transmitted only if it is exported and not a chan or func field
+// or pointer to chan or func.
+func isSent(field *reflect.StructField) bool {
+	if !isExported(field.Name) {
+		return false
+	}
+	// If the field is a chan or func or pointer thereto, don't send it.
+	// That is, treat it like an unexported field.
+	typ := field.Type
+	for typ.Kind() == reflect.Ptr {
+		typ = typ.Elem()
+	}
+	if typ.Kind() == reflect.Chan || typ.Kind() == reflect.Func {
+		return false
+	}
+	return true
+}
+
 // getBaseType returns the Gob type describing the given reflect.Type's base type.
 // typeLock must be held.
 func getBaseType(name string, rt reflect.Type) (gobType, error) {
@@ -593,11 +639,13 @@ func bootstrapType(name string, e interface{}, expect typeId) typeId {
 // To maintain binary compatibility, if you extend this type, always put
 // the new fields last.
 type wireType struct {
-	ArrayT      *arrayType
-	SliceT      *sliceType
-	StructT     *structType
-	MapT        *mapType
-	GobEncoderT *gobEncoderType
+	ArrayT           *arrayType
+	SliceT           *sliceType
+	StructT          *structType
+	MapT             *mapType
+	GobEncoderT      *gobEncoderType
+	BinaryMarshalerT *gobEncoderType
+	TextMarshalerT   *gobEncoderType
 }
 
 func (w *wireType) string() string {
@@ -616,6 +664,10 @@ func (w *wireType) string() string {
 		return w.MapT.Name
 	case w.GobEncoderT != nil:
 		return w.GobEncoderT.Name
+	case w.BinaryMarshalerT != nil:
+		return w.BinaryMarshalerT.Name
+	case w.TextMarshalerT != nil:
+		return w.TextMarshalerT.Name
 	}
 	return unknown
 }
@@ -631,7 +683,7 @@ var typeInfoMap = make(map[reflect.Type]*typeInfo) // protected by typeLock
 // typeLock must be held.
 func getTypeInfo(ut *userTypeInfo) (*typeInfo, error) {
 	rt := ut.base
-	if ut.isGobEncoder {
+	if ut.externalEnc != 0 {
 		// We want the user type, not the base type.
 		rt = ut.user
 	}
@@ -646,12 +698,20 @@ func getTypeInfo(ut *userTypeInfo) (*typeInfo, error) {
 	}
 	info.id = gt.id()
 
-	if ut.isGobEncoder {
+	if ut.externalEnc != 0 {
 		userType, err := getType(rt.Name(), ut, rt)
 		if err != nil {
 			return nil, err
 		}
-		info.wire = &wireType{GobEncoderT: userType.id().gobType().(*gobEncoderType)}
+		gt := userType.id().gobType().(*gobEncoderType)
+		switch ut.externalEnc {
+		case xGob:
+			info.wire = &wireType{GobEncoderT: gt}
+		case xBinary:
+			info.wire = &wireType{BinaryMarshalerT: gt}
+		case xText:
+			info.wire = &wireType{TextMarshalerT: gt}
+		}
 		typeInfoMap[ut.user] = info
 		return info, nil
 	}
diff --git a/libgo/go/encoding/json/decode.go b/libgo/go/encoding/json/decode.go
index 62ac294..458fb39 100644
--- a/libgo/go/encoding/json/decode.go
+++ b/libgo/go/encoding/json/decode.go
@@ -8,6 +8,7 @@
 package json
 
 import (
+	"encoding"
 	"encoding/base64"
 	"errors"
 	"fmt"
@@ -37,9 +38,7 @@ import (
 // keys to the keys used by Marshal (either the struct field name or its tag),
 // preferring an exact match but also accepting a case-insensitive match.
 //
-// To unmarshal JSON into an interface value, Unmarshal unmarshals
-// the JSON into the concrete value contained in the interface value.
-// If the interface value is nil, that is, has no concrete value stored in it,
+// To unmarshal JSON into an interface value,
 // Unmarshal stores one of these in the interface value:
 //
 //	bool, for JSON booleans
@@ -293,7 +292,7 @@ func (d *decodeState) value(v reflect.Value) {
 // until it gets to a non-pointer.
 // if it encounters an Unmarshaler, indirect stops and returns that.
 // if decodingNull is true, indirect stops at the last pointer so it can be set to nil.
-func (d *decodeState) indirect(v reflect.Value, decodingNull bool) (Unmarshaler, reflect.Value) {
+func (d *decodeState) indirect(v reflect.Value, decodingNull bool) (Unmarshaler, encoding.TextUnmarshaler, reflect.Value) {
 	// If v is a named type and is addressable,
 	// start with its address, so that if the type has pointer methods,
 	// we find them.
@@ -322,28 +321,38 @@ func (d *decodeState) indirect(v reflect.Value, decodingNull bool) (Unmarshaler,
 			v.Set(reflect.New(v.Type().Elem()))
 		}
 		if v.Type().NumMethod() > 0 {
-			if unmarshaler, ok := v.Interface().(Unmarshaler); ok {
-				return unmarshaler, reflect.Value{}
+			if u, ok := v.Interface().(Unmarshaler); ok {
+				return u, nil, reflect.Value{}
+			}
+			if u, ok := v.Interface().(encoding.TextUnmarshaler); ok {
+				return nil, u, reflect.Value{}
 			}
 		}
 		v = v.Elem()
 	}
-	return nil, v
+	return nil, nil, v
 }
 
 // array consumes an array from d.data[d.off-1:], decoding into the value v.
 // the first byte of the array ('[') has been read already.
 func (d *decodeState) array(v reflect.Value) {
 	// Check for unmarshaler.
-	unmarshaler, pv := d.indirect(v, false)
-	if unmarshaler != nil {
+	u, ut, pv := d.indirect(v, false)
+	if u != nil {
 		d.off--
-		err := unmarshaler.UnmarshalJSON(d.next())
+		err := u.UnmarshalJSON(d.next())
 		if err != nil {
 			d.error(err)
 		}
 		return
 	}
+	if ut != nil {
+		d.saveError(&UnmarshalTypeError{"array", v.Type()})
+		d.off--
+		d.next()
+		return
+	}
+
 	v = pv
 
 	// Check type of target.
@@ -434,15 +443,21 @@ func (d *decodeState) array(v reflect.Value) {
 // the first byte of the object ('{') has been read already.
 func (d *decodeState) object(v reflect.Value) {
 	// Check for unmarshaler.
-	unmarshaler, pv := d.indirect(v, false)
-	if unmarshaler != nil {
+	u, ut, pv := d.indirect(v, false)
+	if u != nil {
 		d.off--
-		err := unmarshaler.UnmarshalJSON(d.next())
+		err := u.UnmarshalJSON(d.next())
 		if err != nil {
 			d.error(err)
 		}
 		return
 	}
+	if ut != nil {
+		d.saveError(&UnmarshalTypeError{"object", v.Type()})
+		d.off--
+		d.next() // skip over { } in input
+		return
+	}
 	v = pv
 
 	// Decoding into nil interface?  Switch to non-reflect code.
@@ -611,14 +626,37 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value, fromQuoted bool
 		return
 	}
 	wantptr := item[0] == 'n' // null
-	unmarshaler, pv := d.indirect(v, wantptr)
-	if unmarshaler != nil {
-		err := unmarshaler.UnmarshalJSON(item)
+	u, ut, pv := d.indirect(v, wantptr)
+	if u != nil {
+		err := u.UnmarshalJSON(item)
+		if err != nil {
+			d.error(err)
+		}
+		return
+	}
+	if ut != nil {
+		if item[0] != '"' {
+			if fromQuoted {
+				d.saveError(fmt.Errorf("json: invalid use of ,string struct tag, trying to unmarshal %q into %v", item, v.Type()))
+			} else {
+				d.saveError(&UnmarshalTypeError{"string", v.Type()})
+			}
+		}
+		s, ok := unquoteBytes(item)
+		if !ok {
+			if fromQuoted {
+				d.error(fmt.Errorf("json: invalid use of ,string struct tag, trying to unmarshal %q into %v", item, v.Type()))
+			} else {
+				d.error(errPhase)
+			}
+		}
+		err := ut.UnmarshalText(s)
 		if err != nil {
 			d.error(err)
 		}
 		return
 	}
+
 	v = pv
 
 	switch c := item[0]; c {
diff --git a/libgo/go/encoding/json/decode_test.go b/libgo/go/encoding/json/decode_test.go
index f845f69..22c5f89 100644
--- a/libgo/go/encoding/json/decode_test.go
+++ b/libgo/go/encoding/json/decode_test.go
@@ -6,6 +6,7 @@ package json
 
 import (
 	"bytes"
+	"encoding"
 	"fmt"
 	"image"
 	"reflect"
@@ -50,8 +51,6 @@ type tx struct {
 	x int
 }
 
-var txType = reflect.TypeOf((*tx)(nil)).Elem()
-
 // A type that can unmarshal itself.
 
 type unmarshaler struct {
@@ -59,7 +58,7 @@ type unmarshaler struct {
 }
 
 func (u *unmarshaler) UnmarshalJSON(b []byte) error {
-	*u = unmarshaler{true} // All we need to see that UnmarshalJson is called.
+	*u = unmarshaler{true} // All we need to see that UnmarshalJSON is called.
 	return nil
 }
 
@@ -67,6 +66,26 @@ type ustruct struct {
 	M unmarshaler
 }
 
+type unmarshalerText struct {
+	T bool
+}
+
+// needed for re-marshaling tests
+func (u *unmarshalerText) MarshalText() ([]byte, error) {
+	return []byte(""), nil
+}
+
+func (u *unmarshalerText) UnmarshalText(b []byte) error {
+	*u = unmarshalerText{true} // All we need to see that UnmarshalText is called.
+	return nil
+}
+
+var _ encoding.TextUnmarshaler = (*unmarshalerText)(nil)
+
+type ustructText struct {
+	M unmarshalerText
+}
+
 var (
 	um0, um1 unmarshaler // target2 of unmarshaling
 	ump      = &um1
@@ -74,6 +93,13 @@ var (
 	umslice  = []unmarshaler{{true}}
 	umslicep = new([]unmarshaler)
 	umstruct = ustruct{unmarshaler{true}}
+
+	um0T, um1T unmarshalerText // target2 of unmarshaling
+	umpT       = &um1T
+	umtrueT    = unmarshalerText{true}
+	umsliceT   = []unmarshalerText{{true}}
+	umslicepT  = new([]unmarshalerText)
+	umstructT  = ustructText{unmarshalerText{true}}
 )
 
 // Test data structures for anonymous fields.
@@ -184,6 +210,12 @@ type Ambig struct {
 	Second int `json:"Hello"`
 }
 
+type XYZ struct {
+	X interface{}
+	Y interface{}
+	Z interface{}
+}
+
 var unmarshalTests = []unmarshalTest{
 	// basic types
 	{in: `true`, ptr: new(bool), out: true},
@@ -263,6 +295,13 @@ var unmarshalTests = []unmarshalTest{
 	{in: `[{"T":false}]`, ptr: &umslicep, out: &umslice},
 	{in: `{"M":{"T":false}}`, ptr: &umstruct, out: umstruct},
 
+	// UnmarshalText interface test
+	{in: `"X"`, ptr: &um0T, out: umtrueT}, // use "false" so test will fail if custom unmarshaler is not called
+	{in: `"X"`, ptr: &umpT, out: &umtrueT},
+	{in: `["X"]`, ptr: &umsliceT, out: umsliceT},
+	{in: `["X"]`, ptr: &umslicepT, out: &umsliceT},
+	{in: `{"M":"X"}`, ptr: &umstructT, out: umstructT},
+
 	{
 		in: `{
 			"Level0": 1,
@@ -391,17 +430,23 @@ func TestMarshal(t *testing.T) {
 	}
 }
 
+var badUTF8 = []struct {
+	in, out string
+}{
+	{"hello\xffworld", `"hello\ufffdworld"`},
+	{"", `""`},
+	{"\xff", `"\ufffd"`},
+	{"\xff\xff", `"\ufffd\ufffd"`},
+	{"a\xffb", `"a\ufffdb"`},
+	{"\xe6\x97\xa5\xe6\x9c\xac\xff\xaa\x9e", `"日本\ufffd\ufffd\ufffd"`},
+}
+
 func TestMarshalBadUTF8(t *testing.T) {
-	s := "hello\xffworld"
-	b, err := Marshal(s)
-	if err == nil {
-		t.Fatal("Marshal bad UTF8: no error")
-	}
-	if len(b) != 0 {
-		t.Fatal("Marshal returned data")
-	}
-	if _, ok := err.(*InvalidUTF8Error); !ok {
-		t.Fatalf("Marshal did not return InvalidUTF8Error: %T %v", err, err)
+	for _, tt := range badUTF8 {
+		b, err := Marshal(tt.in)
+		if string(b) != tt.out || err != nil {
+			t.Errorf("Marshal(%q) = %#q, %v, want %#q, nil", tt.in, b, err, tt.out)
+		}
 	}
 }
 
@@ -417,6 +462,45 @@ func TestMarshalNumberZeroVal(t *testing.T) {
 	}
 }
 
+func TestMarshalEmbeds(t *testing.T) {
+	top := &Top{
+		Level0: 1,
+		Embed0: Embed0{
+			Level1b: 2,
+			Level1c: 3,
+		},
+		Embed0a: &Embed0a{
+			Level1a: 5,
+			Level1b: 6,
+		},
+		Embed0b: &Embed0b{
+			Level1a: 8,
+			Level1b: 9,
+			Level1c: 10,
+			Level1d: 11,
+			Level1e: 12,
+		},
+		Loop: Loop{
+			Loop1: 13,
+			Loop2: 14,
+		},
+		Embed0p: Embed0p{
+			Point: image.Point{X: 15, Y: 16},
+		},
+		Embed0q: Embed0q{
+			Point: Point{Z: 17},
+		},
+	}
+	b, err := Marshal(top)
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := "{\"Level0\":1,\"Level1b\":2,\"Level1c\":3,\"Level1a\":5,\"LEVEL1B\":6,\"e\":{\"Level1a\":8,\"Level1b\":9,\"Level1c\":10,\"Level1d\":11,\"x\":12},\"Loop1\":13,\"Loop2\":14,\"X\":15,\"Y\":16,\"Z\":17}"
+	if string(b) != want {
+		t.Errorf("Wrong marshal result.\n got: %q\nwant: %q", b, want)
+	}
+}
+
 func TestUnmarshal(t *testing.T) {
 	for i, tt := range unmarshalTests {
 		var scan scanner
@@ -432,7 +516,7 @@ func TestUnmarshal(t *testing.T) {
 		}
 		// v = new(right-type)
 		v := reflect.New(reflect.TypeOf(tt.ptr).Elem())
-		dec := NewDecoder(bytes.NewBuffer(in))
+		dec := NewDecoder(bytes.NewReader(in))
 		if tt.useNumber {
 			dec.UseNumber()
 		}
@@ -457,16 +541,18 @@ func TestUnmarshal(t *testing.T) {
 				continue
 			}
 			vv := reflect.New(reflect.TypeOf(tt.ptr).Elem())
-			dec = NewDecoder(bytes.NewBuffer(enc))
+			dec = NewDecoder(bytes.NewReader(enc))
 			if tt.useNumber {
 				dec.UseNumber()
 			}
 			if err := dec.Decode(vv.Interface()); err != nil {
-				t.Errorf("#%d: error re-unmarshaling: %v", i, err)
+				t.Errorf("#%d: error re-unmarshaling %#q: %v", i, enc, err)
 				continue
 			}
 			if !reflect.DeepEqual(v.Elem().Interface(), vv.Elem().Interface()) {
 				t.Errorf("#%d: mismatch\nhave: %#+v\nwant: %#+v", i, v.Elem().Interface(), vv.Elem().Interface())
+				t.Errorf("     In: %q", strings.Map(noSpace, string(in)))
+				t.Errorf("Marshal: %q", strings.Map(noSpace, string(enc)))
 				continue
 			}
 		}
@@ -568,14 +654,14 @@ func TestUnmarshalPtrPtr(t *testing.T) {
 }
 
 func TestEscape(t *testing.T) {
-	const input = `"foobar"<html>`
-	const expected = `"\"foobar\"\u003chtml\u003e"`
+	const input = `"foobar"<html>` + " [\u2028 \u2029]"
+	const expected = `"\"foobar\"\u003chtml\u003e [\u2028 \u2029]"`
 	b, err := Marshal(input)
 	if err != nil {
 		t.Fatalf("Marshal error: %v", err)
 	}
 	if s := string(b); s != expected {
-		t.Errorf("Encoding of [%s] was [%s], want [%s]", input, s, expected)
+		t.Errorf("Encoding of [%s]:\n got [%s]\nwant [%s]", input, s, expected)
 	}
 }
 
@@ -934,15 +1020,20 @@ func TestRefUnmarshal(t *testing.T) {
 		// Ref is defined in encode_test.go.
 		R0 Ref
 		R1 *Ref
+		R2 RefText
+		R3 *RefText
 	}
 	want := S{
 		R0: 12,
 		R1: new(Ref),
+		R2: 13,
+		R3: new(RefText),
 	}
 	*want.R1 = 12
+	*want.R3 = 13
 
 	var got S
-	if err := Unmarshal([]byte(`{"R0":"ref","R1":"ref"}`), &got); err != nil {
+	if err := Unmarshal([]byte(`{"R0":"ref","R1":"ref","R2":"ref","R3":"ref"}`), &got); err != nil {
 		t.Fatalf("Unmarshal: %v", err)
 	}
 	if !reflect.DeepEqual(got, want) {
@@ -1064,7 +1155,6 @@ func TestUnmarshalNulls(t *testing.T) {
 
 func TestStringKind(t *testing.T) {
 	type stringKind string
-	type aMap map[stringKind]int
 
 	var m1, m2 map[stringKind]int
 	m1 = map[stringKind]int{
@@ -1191,3 +1281,38 @@ func TestSkipArrayObjects(t *testing.T) {
 		t.Errorf("got error %q, want nil", err)
 	}
 }
+
+// Test semantics of pre-filled struct fields and pre-filled map fields.
+// Issue 4900.
+func TestPrefilled(t *testing.T) {
+	ptrToMap := func(m map[string]interface{}) *map[string]interface{} { return &m }
+
+	// Values here change, cannot reuse table across runs.
+	var prefillTests = []struct {
+		in  string
+		ptr interface{}
+		out interface{}
+	}{
+		{
+			in:  `{"X": 1, "Y": 2}`,
+			ptr: &XYZ{X: float32(3), Y: int16(4), Z: 1.5},
+			out: &XYZ{X: float64(1), Y: float64(2), Z: 1.5},
+		},
+		{
+			in:  `{"X": 1, "Y": 2}`,
+			ptr: ptrToMap(map[string]interface{}{"X": float32(3), "Y": int16(4), "Z": 1.5}),
+			out: ptrToMap(map[string]interface{}{"X": float64(1), "Y": float64(2), "Z": 1.5}),
+		},
+	}
+
+	for _, tt := range prefillTests {
+		ptrstr := fmt.Sprintf("%v", tt.ptr)
+		err := Unmarshal([]byte(tt.in), tt.ptr) // tt.ptr edited here
+		if err != nil {
+			t.Errorf("Unmarshal: %v", err)
+		}
+		if !reflect.DeepEqual(tt.ptr, tt.out) {
+			t.Errorf("Unmarshal(%#q, %s): have %v, want %v", tt.in, ptrstr, tt.ptr, tt.out)
+		}
+	}
+}
diff --git a/libgo/go/encoding/json/encode.go b/libgo/go/encoding/json/encode.go
index 85727ba..7d6c71d 100644
--- a/libgo/go/encoding/json/encode.go
+++ b/libgo/go/encoding/json/encode.go
@@ -12,6 +12,7 @@ package json
 
 import (
 	"bytes"
+	"encoding"
 	"encoding/base64"
 	"math"
 	"reflect"
@@ -149,14 +150,14 @@ func MarshalIndent(v interface{}, prefix, indent string) ([]byte, error) {
 	return buf.Bytes(), nil
 }
 
-// HTMLEscape appends to dst the JSON-encoded src with <, >, and &
-// characters inside string literals changed to \u003c, \u003e, \u0026
+// HTMLEscape appends to dst the JSON-encoded src with <, >, &, U+2028 and U+2029
+// characters inside string literals changed to \u003c, \u003e, \u0026, \u2028, \u2029
 // so that the JSON will be safe to embed inside HTML <script> tags.
 // For historical reasons, web browsers don't honor standard HTML
 // escaping within <script> tags, so an alternative JSON encoding must
 // be used.
 func HTMLEscape(dst *bytes.Buffer, src []byte) {
-	// < > & can only appear in string literals,
+	// The characters can only appear in string literals,
 	// so just scan the string one byte at a time.
 	start := 0
 	for i, c := range src {
@@ -169,6 +170,15 @@ func HTMLEscape(dst *bytes.Buffer, src []byte) {
 			dst.WriteByte(hex[c&0xF])
 			start = i + 1
 		}
+		// Convert U+2028 and U+2029 (E2 80 A8 and E2 80 A9).
+		if c == 0xE2 && i+2 < len(src) && src[i+1] == 0x80 && src[i+2]&^1 == 0xA8 {
+			if start < i {
+				dst.Write(src[start:i])
+			}
+			dst.WriteString(`\u202`)
+			dst.WriteByte(hex[src[i+2]&0xF])
+			start = i + 3
+		}
 	}
 	if start < len(src) {
 		dst.Write(src[start:])
@@ -200,8 +210,12 @@ func (e *UnsupportedValueError) Error() string {
 	return "json: unsupported value: " + e.Str
 }
 
-// An InvalidUTF8Error is returned by Marshal when attempting
-// to encode a string value with invalid UTF-8 sequences.
+// Before Go 1.2, an InvalidUTF8Error was returned by Marshal when
+// attempting to encode a string value with invalid UTF-8 sequences.
+// As of Go 1.2, Marshal instead coerces the string to valid UTF-8 by
+// replacing invalid bytes with the Unicode replacement rune U+FFFD.
+// This error is no longer generated but is kept for backwards compatibility
+// with programs that might mention it.
 type InvalidUTF8Error struct {
 	S string // the whole string value that caused the error
 }
@@ -227,12 +241,35 @@ type encodeState struct {
 	scratch      [64]byte
 }
 
+// TODO(bradfitz): use a sync.Cache here
+var encodeStatePool = make(chan *encodeState, 8)
+
+func newEncodeState() *encodeState {
+	select {
+	case e := <-encodeStatePool:
+		e.Reset()
+		return e
+	default:
+		return new(encodeState)
+	}
+}
+
+func putEncodeState(e *encodeState) {
+	select {
+	case encodeStatePool <- e:
+	default:
+	}
+}
+
 func (e *encodeState) marshal(v interface{}) (err error) {
 	defer func() {
 		if r := recover(); r != nil {
 			if _, ok := r.(runtime.Error); ok {
 				panic(r)
 			}
+			if s, ok := r.(string); ok {
+				panic(s)
+			}
 			err = r.(error)
 		}
 	}()
@@ -265,186 +302,438 @@ func isEmptyValue(v reflect.Value) bool {
 }
 
 func (e *encodeState) reflectValue(v reflect.Value) {
-	e.reflectValueQuoted(v, false)
+	valueEncoder(v)(e, v, false)
+}
+
+type encoderFunc func(e *encodeState, v reflect.Value, quoted bool)
+
+var encoderCache struct {
+	sync.RWMutex
+	m map[reflect.Type]encoderFunc
 }
 
-// reflectValueQuoted writes the value in v to the output.
-// If quoted is true, the serialization is wrapped in a JSON string.
-func (e *encodeState) reflectValueQuoted(v reflect.Value, quoted bool) {
+func valueEncoder(v reflect.Value) encoderFunc {
 	if !v.IsValid() {
-		e.WriteString("null")
-		return
+		return invalidValueEncoder
 	}
+	return typeEncoder(v.Type())
+}
 
-	m, ok := v.Interface().(Marshaler)
-	if !ok {
-		// T doesn't match the interface. Check against *T too.
-		if v.Kind() != reflect.Ptr && v.CanAddr() {
-			m, ok = v.Addr().Interface().(Marshaler)
-			if ok {
-				v = v.Addr()
-			}
-		}
+func typeEncoder(t reflect.Type) encoderFunc {
+	encoderCache.RLock()
+	f := encoderCache.m[t]
+	encoderCache.RUnlock()
+	if f != nil {
+		return f
+	}
+
+	// To deal with recursive types, populate the map with an
+	// indirect func before we build it. This type waits on the
+	// real func (f) to be ready and then calls it.  This indirect
+	// func is only used for recursive types.
+	encoderCache.Lock()
+	if encoderCache.m == nil {
+		encoderCache.m = make(map[reflect.Type]encoderFunc)
+	}
+	var wg sync.WaitGroup
+	wg.Add(1)
+	encoderCache.m[t] = func(e *encodeState, v reflect.Value, quoted bool) {
+		wg.Wait()
+		f(e, v, quoted)
+	}
+	encoderCache.Unlock()
+
+	// Compute fields without lock.
+	// Might duplicate effort but won't hold other computations back.
+	f = newTypeEncoder(t, true)
+	wg.Done()
+	encoderCache.Lock()
+	encoderCache.m[t] = f
+	encoderCache.Unlock()
+	return f
+}
+
+var (
+	marshalerType     = reflect.TypeOf(new(Marshaler)).Elem()
+	textMarshalerType = reflect.TypeOf(new(encoding.TextMarshaler)).Elem()
+)
+
+// newTypeEncoder constructs an encoderFunc for a type.
+// The returned encoder only checks CanAddr when allowAddr is true.
+func newTypeEncoder(t reflect.Type, allowAddr bool) encoderFunc {
+	if t.Implements(marshalerType) {
+		return marshalerEncoder
 	}
-	if ok && (v.Kind() != reflect.Ptr || !v.IsNil()) {
-		b, err := m.MarshalJSON()
-		if err == nil {
-			// copy JSON into buffer, checking validity.
-			err = compact(&e.Buffer, b, true)
+	if t.Kind() != reflect.Ptr && allowAddr {
+		if reflect.PtrTo(t).Implements(marshalerType) {
+			return newCondAddrEncoder(addrMarshalerEncoder, newTypeEncoder(t, false))
 		}
-		if err != nil {
-			e.error(&MarshalerError{v.Type(), err})
+	}
+
+	if t.Implements(textMarshalerType) {
+		return textMarshalerEncoder
+	}
+	if t.Kind() != reflect.Ptr && allowAddr {
+		if reflect.PtrTo(t).Implements(textMarshalerType) {
+			return newCondAddrEncoder(addrTextMarshalerEncoder, newTypeEncoder(t, false))
 		}
+	}
+
+	switch t.Kind() {
+	case reflect.Bool:
+		return boolEncoder
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return intEncoder
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return uintEncoder
+	case reflect.Float32:
+		return float32Encoder
+	case reflect.Float64:
+		return float64Encoder
+	case reflect.String:
+		return stringEncoder
+	case reflect.Interface:
+		return interfaceEncoder
+	case reflect.Struct:
+		return newStructEncoder(t)
+	case reflect.Map:
+		return newMapEncoder(t)
+	case reflect.Slice:
+		return newSliceEncoder(t)
+	case reflect.Array:
+		return newArrayEncoder(t)
+	case reflect.Ptr:
+		return newPtrEncoder(t)
+	default:
+		return unsupportedTypeEncoder
+	}
+}
+
+func invalidValueEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	e.WriteString("null")
+}
+
+func marshalerEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	if v.Kind() == reflect.Ptr && v.IsNil() {
+		e.WriteString("null")
+		return
+	}
+	m := v.Interface().(Marshaler)
+	b, err := m.MarshalJSON()
+	if err == nil {
+		// copy JSON into buffer, checking validity.
+		err = compact(&e.Buffer, b, true)
+	}
+	if err != nil {
+		e.error(&MarshalerError{v.Type(), err})
+	}
+}
+
+func addrMarshalerEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	va := v.Addr()
+	if va.IsNil() {
+		e.WriteString("null")
 		return
 	}
+	m := va.Interface().(Marshaler)
+	b, err := m.MarshalJSON()
+	if err == nil {
+		// copy JSON into buffer, checking validity.
+		err = compact(&e.Buffer, b, true)
+	}
+	if err != nil {
+		e.error(&MarshalerError{v.Type(), err})
+	}
+}
 
-	writeString := (*encodeState).WriteString
+func textMarshalerEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	if v.Kind() == reflect.Ptr && v.IsNil() {
+		e.WriteString("null")
+		return
+	}
+	m := v.Interface().(encoding.TextMarshaler)
+	b, err := m.MarshalText()
+	if err == nil {
+		_, err = e.stringBytes(b)
+	}
+	if err != nil {
+		e.error(&MarshalerError{v.Type(), err})
+	}
+}
+
+func addrTextMarshalerEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	va := v.Addr()
+	if va.IsNil() {
+		e.WriteString("null")
+		return
+	}
+	m := va.Interface().(encoding.TextMarshaler)
+	b, err := m.MarshalText()
+	if err == nil {
+		_, err = e.stringBytes(b)
+	}
+	if err != nil {
+		e.error(&MarshalerError{v.Type(), err})
+	}
+}
+
+func boolEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	if quoted {
+		e.WriteByte('"')
+	}
+	if v.Bool() {
+		e.WriteString("true")
+	} else {
+		e.WriteString("false")
+	}
+	if quoted {
+		e.WriteByte('"')
+	}
+}
+
+func intEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	b := strconv.AppendInt(e.scratch[:0], v.Int(), 10)
+	if quoted {
+		e.WriteByte('"')
+	}
+	e.Write(b)
 	if quoted {
-		writeString = (*encodeState).string
+		e.WriteByte('"')
 	}
+}
 
-	switch v.Kind() {
-	case reflect.Bool:
-		x := v.Bool()
-		if x {
-			writeString(e, "true")
-		} else {
-			writeString(e, "false")
-		}
+func uintEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	b := strconv.AppendUint(e.scratch[:0], v.Uint(), 10)
+	if quoted {
+		e.WriteByte('"')
+	}
+	e.Write(b)
+	if quoted {
+		e.WriteByte('"')
+	}
+}
 
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		b := strconv.AppendInt(e.scratch[:0], v.Int(), 10)
-		if quoted {
-			writeString(e, string(b))
-		} else {
-			e.Write(b)
+type floatEncoder int // number of bits
+
+func (bits floatEncoder) encode(e *encodeState, v reflect.Value, quoted bool) {
+	f := v.Float()
+	if math.IsInf(f, 0) || math.IsNaN(f) {
+		e.error(&UnsupportedValueError{v, strconv.FormatFloat(f, 'g', -1, int(bits))})
+	}
+	b := strconv.AppendFloat(e.scratch[:0], f, 'g', -1, int(bits))
+	if quoted {
+		e.WriteByte('"')
+	}
+	e.Write(b)
+	if quoted {
+		e.WriteByte('"')
+	}
+}
+
+var (
+	float32Encoder = (floatEncoder(32)).encode
+	float64Encoder = (floatEncoder(64)).encode
+)
+
+func stringEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	if v.Type() == numberType {
+		numStr := v.String()
+		if numStr == "" {
+			numStr = "0" // Number's zero-val
 		}
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-		b := strconv.AppendUint(e.scratch[:0], v.Uint(), 10)
-		if quoted {
-			writeString(e, string(b))
-		} else {
-			e.Write(b)
+		e.WriteString(numStr)
+		return
+	}
+	if quoted {
+		sb, err := Marshal(v.String())
+		if err != nil {
+			e.error(err)
 		}
-	case reflect.Float32, reflect.Float64:
-		f := v.Float()
-		if math.IsInf(f, 0) || math.IsNaN(f) {
-			e.error(&UnsupportedValueError{v, strconv.FormatFloat(f, 'g', -1, v.Type().Bits())})
+		e.string(string(sb))
+	} else {
+		e.string(v.String())
+	}
+}
+
+func interfaceEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	if v.IsNil() {
+		e.WriteString("null")
+		return
+	}
+	e.reflectValue(v.Elem())
+}
+
+func unsupportedTypeEncoder(e *encodeState, v reflect.Value, quoted bool) {
+	e.error(&UnsupportedTypeError{v.Type()})
+}
+
+type structEncoder struct {
+	fields    []field
+	fieldEncs []encoderFunc
+}
+
+func (se *structEncoder) encode(e *encodeState, v reflect.Value, quoted bool) {
+	e.WriteByte('{')
+	first := true
+	for i, f := range se.fields {
+		fv := fieldByIndex(v, f.index)
+		if !fv.IsValid() || f.omitEmpty && isEmptyValue(fv) {
+			continue
 		}
-		b := strconv.AppendFloat(e.scratch[:0], f, 'g', -1, v.Type().Bits())
-		if quoted {
-			writeString(e, string(b))
+		if first {
+			first = false
 		} else {
-			e.Write(b)
-		}
-	case reflect.String:
-		if v.Type() == numberType {
-			numStr := v.String()
-			if numStr == "" {
-				numStr = "0" // Number's zero-val
-			}
-			e.WriteString(numStr)
-			break
-		}
-		if quoted {
-			sb, err := Marshal(v.String())
-			if err != nil {
-				e.error(err)
-			}
-			e.string(string(sb))
-		} else {
-			e.string(v.String())
+			e.WriteByte(',')
 		}
+		e.string(f.name)
+		e.WriteByte(':')
+		se.fieldEncs[i](e, fv, f.quoted)
+	}
+	e.WriteByte('}')
+}
 
-	case reflect.Struct:
-		e.WriteByte('{')
-		first := true
-		for _, f := range cachedTypeFields(v.Type()) {
-			fv := fieldByIndex(v, f.index)
-			if !fv.IsValid() || f.omitEmpty && isEmptyValue(fv) {
-				continue
-			}
-			if first {
-				first = false
-			} else {
-				e.WriteByte(',')
-			}
-			e.string(f.name)
-			e.WriteByte(':')
-			e.reflectValueQuoted(fv, f.quoted)
-		}
-		e.WriteByte('}')
+func newStructEncoder(t reflect.Type) encoderFunc {
+	fields := cachedTypeFields(t)
+	se := &structEncoder{
+		fields:    fields,
+		fieldEncs: make([]encoderFunc, len(fields)),
+	}
+	for i, f := range fields {
+		se.fieldEncs[i] = typeEncoder(typeByIndex(t, f.index))
+	}
+	return se.encode
+}
 
-	case reflect.Map:
-		if v.Type().Key().Kind() != reflect.String {
-			e.error(&UnsupportedTypeError{v.Type()})
-		}
-		if v.IsNil() {
-			e.WriteString("null")
-			break
-		}
-		e.WriteByte('{')
-		var sv stringValues = v.MapKeys()
-		sort.Sort(sv)
-		for i, k := range sv {
-			if i > 0 {
-				e.WriteByte(',')
-			}
-			e.string(k.String())
-			e.WriteByte(':')
-			e.reflectValue(v.MapIndex(k))
-		}
-		e.WriteByte('}')
+type mapEncoder struct {
+	elemEnc encoderFunc
+}
 
-	case reflect.Slice:
-		if v.IsNil() {
-			e.WriteString("null")
-			break
-		}
-		if v.Type().Elem().Kind() == reflect.Uint8 {
-			// Byte slices get special treatment; arrays don't.
-			s := v.Bytes()
-			e.WriteByte('"')
-			if len(s) < 1024 {
-				// for small buffers, using Encode directly is much faster.
-				dst := make([]byte, base64.StdEncoding.EncodedLen(len(s)))
-				base64.StdEncoding.Encode(dst, s)
-				e.Write(dst)
-			} else {
-				// for large buffers, avoid unnecessary extra temporary
-				// buffer space.
-				enc := base64.NewEncoder(base64.StdEncoding, e)
-				enc.Write(s)
-				enc.Close()
-			}
-			e.WriteByte('"')
-			break
-		}
-		// Slices can be marshalled as nil, but otherwise are handled
-		// as arrays.
-		fallthrough
-	case reflect.Array:
-		e.WriteByte('[')
-		n := v.Len()
-		for i := 0; i < n; i++ {
-			if i > 0 {
-				e.WriteByte(',')
-			}
-			e.reflectValue(v.Index(i))
+func (me *mapEncoder) encode(e *encodeState, v reflect.Value, _ bool) {
+	if v.IsNil() {
+		e.WriteString("null")
+		return
+	}
+	e.WriteByte('{')
+	var sv stringValues = v.MapKeys()
+	sort.Sort(sv)
+	for i, k := range sv {
+		if i > 0 {
+			e.WriteByte(',')
 		}
-		e.WriteByte(']')
+		e.string(k.String())
+		e.WriteByte(':')
+		me.elemEnc(e, v.MapIndex(k), false)
+	}
+	e.WriteByte('}')
+}
 
-	case reflect.Interface, reflect.Ptr:
-		if v.IsNil() {
-			e.WriteString("null")
-			return
+func newMapEncoder(t reflect.Type) encoderFunc {
+	if t.Key().Kind() != reflect.String {
+		return unsupportedTypeEncoder
+	}
+	me := &mapEncoder{typeEncoder(t.Elem())}
+	return me.encode
+}
+
+func encodeByteSlice(e *encodeState, v reflect.Value, _ bool) {
+	if v.IsNil() {
+		e.WriteString("null")
+		return
+	}
+	s := v.Bytes()
+	e.WriteByte('"')
+	if len(s) < 1024 {
+		// for small buffers, using Encode directly is much faster.
+		dst := make([]byte, base64.StdEncoding.EncodedLen(len(s)))
+		base64.StdEncoding.Encode(dst, s)
+		e.Write(dst)
+	} else {
+		// for large buffers, avoid unnecessary extra temporary
+		// buffer space.
+		enc := base64.NewEncoder(base64.StdEncoding, e)
+		enc.Write(s)
+		enc.Close()
+	}
+	e.WriteByte('"')
+}
+
+// sliceEncoder just wraps an arrayEncoder, checking to make sure the value isn't nil.
+type sliceEncoder struct {
+	arrayEnc encoderFunc
+}
+
+func (se *sliceEncoder) encode(e *encodeState, v reflect.Value, _ bool) {
+	if v.IsNil() {
+		e.WriteString("null")
+		return
+	}
+	se.arrayEnc(e, v, false)
+}
+
+func newSliceEncoder(t reflect.Type) encoderFunc {
+	// Byte slices get special treatment; arrays don't.
+	if t.Elem().Kind() == reflect.Uint8 {
+		return encodeByteSlice
+	}
+	enc := &sliceEncoder{newArrayEncoder(t)}
+	return enc.encode
+}
+
+type arrayEncoder struct {
+	elemEnc encoderFunc
+}
+
+func (ae *arrayEncoder) encode(e *encodeState, v reflect.Value, _ bool) {
+	e.WriteByte('[')
+	n := v.Len()
+	for i := 0; i < n; i++ {
+		if i > 0 {
+			e.WriteByte(',')
 		}
-		e.reflectValue(v.Elem())
+		ae.elemEnc(e, v.Index(i), false)
+	}
+	e.WriteByte(']')
+}
 
-	default:
-		e.error(&UnsupportedTypeError{v.Type()})
+func newArrayEncoder(t reflect.Type) encoderFunc {
+	enc := &arrayEncoder{typeEncoder(t.Elem())}
+	return enc.encode
+}
+
+type ptrEncoder struct {
+	elemEnc encoderFunc
+}
+
+func (pe *ptrEncoder) encode(e *encodeState, v reflect.Value, _ bool) {
+	if v.IsNil() {
+		e.WriteString("null")
+		return
+	}
+	pe.elemEnc(e, v.Elem(), false)
+}
+
+func newPtrEncoder(t reflect.Type) encoderFunc {
+	enc := &ptrEncoder{typeEncoder(t.Elem())}
+	return enc.encode
+}
+
+type condAddrEncoder struct {
+	canAddrEnc, elseEnc encoderFunc
+}
+
+func (ce *condAddrEncoder) encode(e *encodeState, v reflect.Value, quoted bool) {
+	if v.CanAddr() {
+		ce.canAddrEnc(e, v, quoted)
+	} else {
+		ce.elseEnc(e, v, quoted)
 	}
-	return
+}
+
+// newCondAddrEncoder returns an encoder that checks whether its value
+// CanAddr and delegates to canAddrEnc if so, else to elseEnc.
+func newCondAddrEncoder(canAddrEnc, elseEnc encoderFunc) encoderFunc {
+	enc := &condAddrEncoder{canAddrEnc: canAddrEnc, elseEnc: elseEnc}
+	return enc.encode
 }
 
 func isValidTag(s string) bool {
@@ -479,6 +768,16 @@ func fieldByIndex(v reflect.Value, index []int) reflect.Value {
 	return v
 }
 
+func typeByIndex(t reflect.Type, index []int) reflect.Type {
+	for _, i := range index {
+		if t.Kind() == reflect.Ptr {
+			t = t.Elem()
+		}
+		t = t.Field(i).Type
+	}
+	return t
+}
+
 // stringValues is a slice of reflect.Value holding *reflect.StringValue.
 // It implements the methods to sort by string.
 type stringValues []reflect.Value
@@ -488,13 +787,14 @@ func (sv stringValues) Swap(i, j int)      { sv[i], sv[j] = sv[j], sv[i] }
 func (sv stringValues) Less(i, j int) bool { return sv.get(i) < sv.get(j) }
 func (sv stringValues) get(i int) string   { return sv[i].String() }
 
+// NOTE: keep in sync with stringBytes below.
 func (e *encodeState) string(s string) (int, error) {
 	len0 := e.Len()
 	e.WriteByte('"')
 	start := 0
 	for i := 0; i < len(s); {
 		if b := s[i]; b < utf8.RuneSelf {
-			if 0x20 <= b && b != '\\' && b != '"' && b != '<' && b != '>' {
+			if 0x20 <= b && b != '\\' && b != '"' && b != '<' && b != '>' && b != '&' {
 				i++
 				continue
 			}
@@ -526,7 +826,30 @@ func (e *encodeState) string(s string) (int, error) {
 		}
 		c, size := utf8.DecodeRuneInString(s[i:])
 		if c == utf8.RuneError && size == 1 {
-			e.error(&InvalidUTF8Error{s})
+			if start < i {
+				e.WriteString(s[start:i])
+			}
+			e.WriteString(`\ufffd`)
+			i += size
+			start = i
+			continue
+		}
+		// U+2028 is LINE SEPARATOR.
+		// U+2029 is PARAGRAPH SEPARATOR.
+		// They are both technically valid characters in JSON strings,
+		// but don't work in JSONP, which has to be evaluated as JavaScript,
+		// and can lead to security holes there. It is valid JSON to
+		// escape them, so we do so unconditionally.
+		// See http://timelessrepo.com/json-isnt-a-javascript-subset for discussion.
+		if c == '\u2028' || c == '\u2029' {
+			if start < i {
+				e.WriteString(s[start:i])
+			}
+			e.WriteString(`\u202`)
+			e.WriteByte(hex[c&0xF])
+			i += size
+			start = i
+			continue
 		}
 		i += size
 	}
@@ -537,6 +860,79 @@ func (e *encodeState) string(s string) (int, error) {
 	return e.Len() - len0, nil
 }
 
+// NOTE: keep in sync with string above.
+func (e *encodeState) stringBytes(s []byte) (int, error) {
+	len0 := e.Len()
+	e.WriteByte('"')
+	start := 0
+	for i := 0; i < len(s); {
+		if b := s[i]; b < utf8.RuneSelf {
+			if 0x20 <= b && b != '\\' && b != '"' && b != '<' && b != '>' && b != '&' {
+				i++
+				continue
+			}
+			if start < i {
+				e.Write(s[start:i])
+			}
+			switch b {
+			case '\\', '"':
+				e.WriteByte('\\')
+				e.WriteByte(b)
+			case '\n':
+				e.WriteByte('\\')
+				e.WriteByte('n')
+			case '\r':
+				e.WriteByte('\\')
+				e.WriteByte('r')
+			default:
+				// This encodes bytes < 0x20 except for \n and \r,
+				// as well as < and >. The latter are escaped because they
+				// can lead to security holes when user-controlled strings
+				// are rendered into JSON and served to some browsers.
+				e.WriteString(`\u00`)
+				e.WriteByte(hex[b>>4])
+				e.WriteByte(hex[b&0xF])
+			}
+			i++
+			start = i
+			continue
+		}
+		c, size := utf8.DecodeRune(s[i:])
+		if c == utf8.RuneError && size == 1 {
+			if start < i {
+				e.Write(s[start:i])
+			}
+			e.WriteString(`\ufffd`)
+			i += size
+			start = i
+			continue
+		}
+		// U+2028 is LINE SEPARATOR.
+		// U+2029 is PARAGRAPH SEPARATOR.
+		// They are both technically valid characters in JSON strings,
+		// but don't work in JSONP, which has to be evaluated as JavaScript,
+		// and can lead to security holes there. It is valid JSON to
+		// escape them, so we do so unconditionally.
+		// See http://timelessrepo.com/json-isnt-a-javascript-subset for discussion.
+		if c == '\u2028' || c == '\u2029' {
+			if start < i {
+				e.Write(s[start:i])
+			}
+			e.WriteString(`\u202`)
+			e.WriteByte(hex[c&0xF])
+			i += size
+			start = i
+			continue
+		}
+		i += size
+	}
+	if start < len(s) {
+		e.Write(s[start:])
+	}
+	e.WriteByte('"')
+	return e.Len() - len0, nil
+}
+
 // A field represents a single field found in a struct.
 type field struct {
 	name      string
diff --git a/libgo/go/encoding/json/encode_test.go b/libgo/go/encoding/json/encode_test.go
index 5be0a99..9395db7 100644
--- a/libgo/go/encoding/json/encode_test.go
+++ b/libgo/go/encoding/json/encode_test.go
@@ -9,6 +9,7 @@ import (
 	"math"
 	"reflect"
 	"testing"
+	"unicode"
 )
 
 type Optionals struct {
@@ -146,19 +147,46 @@ func (Val) MarshalJSON() ([]byte, error) {
 	return []byte(`"val"`), nil
 }
 
+// RefText has Marshaler and Unmarshaler methods with pointer receiver.
+type RefText int
+
+func (*RefText) MarshalText() ([]byte, error) {
+	return []byte(`"ref"`), nil
+}
+
+func (r *RefText) UnmarshalText([]byte) error {
+	*r = 13
+	return nil
+}
+
+// ValText has Marshaler methods with value receiver.
+type ValText int
+
+func (ValText) MarshalText() ([]byte, error) {
+	return []byte(`"val"`), nil
+}
+
 func TestRefValMarshal(t *testing.T) {
 	var s = struct {
 		R0 Ref
 		R1 *Ref
+		R2 RefText
+		R3 *RefText
 		V0 Val
 		V1 *Val
+		V2 ValText
+		V3 *ValText
 	}{
 		R0: 12,
 		R1: new(Ref),
+		R2: 14,
+		R3: new(RefText),
 		V0: 13,
 		V1: new(Val),
+		V2: 15,
+		V3: new(ValText),
 	}
-	const want = `{"R0":"ref","R1":"ref","V0":"val","V1":"val"}`
+	const want = `{"R0":"ref","R1":"ref","R2":"\"ref\"","R3":"\"ref\"","V0":"val","V1":"val","V2":"\"val\"","V3":"\"val\""}`
 	b, err := Marshal(&s)
 	if err != nil {
 		t.Fatalf("Marshal: %v", err)
@@ -175,15 +203,32 @@ func (C) MarshalJSON() ([]byte, error) {
 	return []byte(`"<&>"`), nil
 }
 
+// CText implements Marshaler and returns unescaped text.
+type CText int
+
+func (CText) MarshalText() ([]byte, error) {
+	return []byte(`"<&>"`), nil
+}
+
 func TestMarshalerEscaping(t *testing.T) {
 	var c C
-	const want = `"\u003c\u0026\u003e"`
+	want := `"\u003c\u0026\u003e"`
 	b, err := Marshal(c)
 	if err != nil {
-		t.Fatalf("Marshal: %v", err)
+		t.Fatalf("Marshal(c): %v", err)
 	}
 	if got := string(b); got != want {
-		t.Errorf("got %q, want %q", got, want)
+		t.Errorf("Marshal(c) = %#q, want %#q", got, want)
+	}
+
+	var ct CText
+	want = `"\"\u003c\u0026\u003e\""`
+	b, err = Marshal(ct)
+	if err != nil {
+		t.Fatalf("Marshal(ct): %v", err)
+	}
+	if got := string(b); got != want {
+		t.Errorf("Marshal(ct) = %#q, want %#q", got, want)
 	}
 }
 
@@ -310,3 +355,73 @@ func TestDuplicatedFieldDisappears(t *testing.T) {
 		t.Fatalf("Marshal: got %s want %s", got, want)
 	}
 }
+
+func TestStringBytes(t *testing.T) {
+	// Test that encodeState.stringBytes and encodeState.string use the same encoding.
+	es := &encodeState{}
+	var r []rune
+	for i := '\u0000'; i <= unicode.MaxRune; i++ {
+		r = append(r, i)
+	}
+	s := string(r) + "\xff\xff\xffhello" // some invalid UTF-8 too
+	_, err := es.string(s)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	esBytes := &encodeState{}
+	_, err = esBytes.stringBytes([]byte(s))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	enc := es.Buffer.String()
+	encBytes := esBytes.Buffer.String()
+	if enc != encBytes {
+		i := 0
+		for i < len(enc) && i < len(encBytes) && enc[i] == encBytes[i] {
+			i++
+		}
+		enc = enc[i:]
+		encBytes = encBytes[i:]
+		i = 0
+		for i < len(enc) && i < len(encBytes) && enc[len(enc)-i-1] == encBytes[len(encBytes)-i-1] {
+			i++
+		}
+		enc = enc[:len(enc)-i]
+		encBytes = encBytes[:len(encBytes)-i]
+
+		if len(enc) > 20 {
+			enc = enc[:20] + "..."
+		}
+		if len(encBytes) > 20 {
+			encBytes = encBytes[:20] + "..."
+		}
+
+		t.Errorf("encodings differ at %#q vs %#q", enc, encBytes)
+	}
+}
+
+func TestIssue6458(t *testing.T) {
+	type Foo struct {
+		M RawMessage
+	}
+	x := Foo{RawMessage(`"foo"`)}
+
+	b, err := Marshal(&x)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if want := `{"M":"foo"}`; string(b) != want {
+		t.Errorf("Marshal(&x) = %#q; want %#q", b, want)
+	}
+
+	b, err = Marshal(x)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if want := `{"M":"ImZvbyI="}`; string(b) != want {
+		t.Errorf("Marshal(x) = %#q; want %#q", b, want)
+	}
+}
diff --git a/libgo/go/encoding/json/indent.go b/libgo/go/encoding/json/indent.go
index e8dfa4e..11ef709 100644
--- a/libgo/go/encoding/json/indent.go
+++ b/libgo/go/encoding/json/indent.go
@@ -27,6 +27,15 @@ func compact(dst *bytes.Buffer, src []byte, escape bool) error {
 			dst.WriteByte(hex[c&0xF])
 			start = i + 1
 		}
+		// Convert U+2028 and U+2029 (E2 80 A8 and E2 80 A9).
+		if c == 0xE2 && i+2 < len(src) && src[i+1] == 0x80 && src[i+2]&^1 == 0xA8 {
+			if start < i {
+				dst.Write(src[start:i])
+			}
+			dst.WriteString(`\u202`)
+			dst.WriteByte(hex[src[i+2]&0xF])
+			start = i + 3
+		}
 		v := scan.step(&scan, int(c))
 		if v >= scanSkipSpace {
 			if v == scanError {
diff --git a/libgo/go/encoding/json/scanner.go b/libgo/go/encoding/json/scanner.go
index 054b6b3..a4609c8 100644
--- a/libgo/go/encoding/json/scanner.go
+++ b/libgo/go/encoding/json/scanner.go
@@ -390,7 +390,7 @@ func stateInStringEscU123(s *scanner, c int) int {
 	return s.error(c, "in \\u hexadecimal character escape")
 }
 
-// stateInStringEscU123 is the state after reading `-` during a number.
+// stateNeg is the state after reading `-` during a number.
 func stateNeg(s *scanner, c int) int {
 	if c == '0' {
 		s.step = state0
diff --git a/libgo/go/encoding/json/scanner_test.go b/libgo/go/encoding/json/scanner_test.go
index 77d3455..90e45ff 100644
--- a/libgo/go/encoding/json/scanner_test.go
+++ b/libgo/go/encoding/json/scanner_test.go
@@ -63,6 +63,25 @@ func TestCompact(t *testing.T) {
 	}
 }
 
+func TestCompactSeparators(t *testing.T) {
+	// U+2028 and U+2029 should be escaped inside strings.
+	// They should not appear outside strings.
+	tests := []struct {
+		in, compact string
+	}{
+		{"{\"\u2028\": 1}", `{"\u2028":1}`},
+		{"{\"\u2029\" :2}", `{"\u2029":2}`},
+	}
+	for _, tt := range tests {
+		var buf bytes.Buffer
+		if err := Compact(&buf, []byte(tt.in)); err != nil {
+			t.Errorf("Compact(%q): %v", tt.in, err)
+		} else if s := buf.String(); s != tt.compact {
+			t.Errorf("Compact(%q) = %q, want %q", tt.in, s, tt.compact)
+		}
+	}
+}
+
 func TestIndent(t *testing.T) {
 	var buf bytes.Buffer
 	for _, tt := range examples {
diff --git a/libgo/go/encoding/json/stream.go b/libgo/go/encoding/json/stream.go
index 00f4726..1928aba 100644
--- a/libgo/go/encoding/json/stream.go
+++ b/libgo/go/encoding/json/stream.go
@@ -148,7 +148,7 @@ func NewEncoder(w io.Writer) *Encoder {
 	return &Encoder{w: w}
 }
 
-// Encode writes the JSON encoding of v to the connection.
+// Encode writes the JSON encoding of v to the stream.
 //
 // See the documentation for Marshal for details about the
 // conversion of Go values to JSON.
@@ -156,8 +156,8 @@ func (enc *Encoder) Encode(v interface{}) error {
 	if enc.err != nil {
 		return enc.err
 	}
-	enc.e.Reset()
-	err := enc.e.marshal(v)
+	e := newEncodeState()
+	err := e.marshal(v)
 	if err != nil {
 		return err
 	}
@@ -168,11 +168,12 @@ func (enc *Encoder) Encode(v interface{}) error {
 	// is required if the encoded value was a number,
 	// so that the reader knows there aren't more
 	// digits coming.
-	enc.e.WriteByte('\n')
+	e.WriteByte('\n')
 
-	if _, err = enc.w.Write(enc.e.Bytes()); err != nil {
+	if _, err = enc.w.Write(e.Bytes()); err != nil {
 		enc.err = err
 	}
+	putEncodeState(e)
 	return err
 }
 
diff --git a/libgo/go/encoding/json/stream_test.go b/libgo/go/encoding/json/stream_test.go
index 07c9e1d..b562e87 100644
--- a/libgo/go/encoding/json/stream_test.go
+++ b/libgo/go/encoding/json/stream_test.go
@@ -191,3 +191,16 @@ func TestBlocking(t *testing.T) {
 		w.Close()
 	}
 }
+
+func BenchmarkEncoderEncode(b *testing.B) {
+	b.ReportAllocs()
+	type T struct {
+		X, Y string
+	}
+	v := &T{"foo", "bar"}
+	for i := 0; i < b.N; i++ {
+		if err := NewEncoder(ioutil.Discard).Encode(v); err != nil {
+			b.Fatal(err)
+		}
+	}
+}
diff --git a/libgo/go/encoding/json/tags.go b/libgo/go/encoding/json/tags.go
index 58cda20..c38fd51 100644
--- a/libgo/go/encoding/json/tags.go
+++ b/libgo/go/encoding/json/tags.go
@@ -21,7 +21,7 @@ func parseTag(tag string) (string, tagOptions) {
 	return tag, tagOptions("")
 }
 
-// Contains returns whether checks that a comma-separated list of options
+// Contains reports whether a comma-separated list of options
 // contains a particular substr flag. substr must be surrounded by a
 // string boundary or commas.
 func (o tagOptions) Contains(optionName string) bool {
diff --git a/libgo/go/encoding/xml/marshal.go b/libgo/go/encoding/xml/marshal.go
index 47b0017..d9522e0 100644
--- a/libgo/go/encoding/xml/marshal.go
+++ b/libgo/go/encoding/xml/marshal.go
@@ -7,12 +7,12 @@ package xml
 import (
 	"bufio"
 	"bytes"
+	"encoding"
 	"fmt"
 	"io"
 	"reflect"
 	"strconv"
 	"strings"
-	"time"
 )
 
 const (
@@ -75,6 +75,41 @@ func Marshal(v interface{}) ([]byte, error) {
 	return b.Bytes(), nil
 }
 
+// Marshaler is the interface implemented by objects that can marshal
+// themselves into valid XML elements.
+//
+// MarshalXML encodes the receiver as zero or more XML elements.
+// By convention, arrays or slices are typically encoded as a sequence
+// of elements, one per entry.
+// Using start as the element tag is not required, but doing so
+// will enable Unmarshal to match the XML elements to the correct
+// struct field.
+// One common implementation strategy is to construct a separate
+// value with a layout corresponding to the desired XML and then
+// to encode it using e.EncodeElement.
+// Another common strategy is to use repeated calls to e.EncodeToken
+// to generate the XML output one token at a time.
+// The sequence of encoded tokens must make up zero or more valid
+// XML elements.
+type Marshaler interface {
+	MarshalXML(e *Encoder, start StartElement) error
+}
+
+// MarshalerAttr is the interface implemented by objects that can marshal
+// themselves into valid XML attributes.
+//
+// MarshalXMLAttr returns an XML attribute with the encoded value of the receiver.
+// Using name as the attribute name is not required, but doing so
+// will enable Unmarshal to match the attribute to the correct
+// struct field.
+// If MarshalXMLAttr returns the zero attribute Attr{}, no attribute
+// will be generated in the output.
+// MarshalXMLAttr is used only for struct fields with the
+// "attr" option in the field tag.
+type MarshalerAttr interface {
+	MarshalXMLAttr(name Name) (Attr, error)
+}
+
 // MarshalIndent works like Marshal, but each XML element begins on a new
 // indented line that starts with prefix and is followed by one or more
 // copies of indent according to the nesting depth.
@@ -90,36 +125,124 @@ func MarshalIndent(v interface{}, prefix, indent string) ([]byte, error) {
 
 // An Encoder writes XML data to an output stream.
 type Encoder struct {
-	printer
+	p printer
 }
 
 // NewEncoder returns a new encoder that writes to w.
 func NewEncoder(w io.Writer) *Encoder {
-	return &Encoder{printer{Writer: bufio.NewWriter(w)}}
+	e := &Encoder{printer{Writer: bufio.NewWriter(w)}}
+	e.p.encoder = e
+	return e
 }
 
 // Indent sets the encoder to generate XML in which each element
 // begins on a new indented line that starts with prefix and is followed by
 // one or more copies of indent according to the nesting depth.
 func (enc *Encoder) Indent(prefix, indent string) {
-	enc.prefix = prefix
-	enc.indent = indent
+	enc.p.prefix = prefix
+	enc.p.indent = indent
 }
 
 // Encode writes the XML encoding of v to the stream.
 //
 // See the documentation for Marshal for details about the conversion
 // of Go values to XML.
+//
+// Encode calls Flush before returning.
 func (enc *Encoder) Encode(v interface{}) error {
-	err := enc.marshalValue(reflect.ValueOf(v), nil)
+	err := enc.p.marshalValue(reflect.ValueOf(v), nil, nil)
 	if err != nil {
 		return err
 	}
-	return enc.Flush()
+	return enc.p.Flush()
+}
+
+// EncodeElement writes the XML encoding of v to the stream,
+// using start as the outermost tag in the encoding.
+//
+// See the documentation for Marshal for details about the conversion
+// of Go values to XML.
+//
+// EncodeElement calls Flush before returning.
+func (enc *Encoder) EncodeElement(v interface{}, start StartElement) error {
+	err := enc.p.marshalValue(reflect.ValueOf(v), nil, &start)
+	if err != nil {
+		return err
+	}
+	return enc.p.Flush()
+}
+
+var (
+	endComment   = []byte("-->")
+	endProcInst  = []byte("?>")
+	endDirective = []byte(">")
+)
+
+// EncodeToken writes the given XML token to the stream.
+// It returns an error if StartElement and EndElement tokens are not properly matched.
+//
+// EncodeToken does not call Flush, because usually it is part of a larger operation
+// such as Encode or EncodeElement (or a custom Marshaler's MarshalXML invoked
+// during those), and those will call Flush when finished.
+//
+// Callers that create an Encoder and then invoke EncodeToken directly, without
+// using Encode or EncodeElement, need to call Flush when finished to ensure
+// that the XML is written to the underlying writer.
+func (enc *Encoder) EncodeToken(t Token) error {
+	p := &enc.p
+	switch t := t.(type) {
+	case StartElement:
+		if err := p.writeStart(&t); err != nil {
+			return err
+		}
+	case EndElement:
+		if err := p.writeEnd(t.Name); err != nil {
+			return err
+		}
+	case CharData:
+		EscapeText(p, t)
+	case Comment:
+		if bytes.Contains(t, endComment) {
+			return fmt.Errorf("xml: EncodeToken of Comment containing --> marker")
+		}
+		p.WriteString("<!--")
+		p.Write(t)
+		p.WriteString("-->")
+		return p.cachedWriteError()
+	case ProcInst:
+		if t.Target == "xml" || !isNameString(t.Target) {
+			return fmt.Errorf("xml: EncodeToken of ProcInst with invalid Target")
+		}
+		if bytes.Contains(t.Inst, endProcInst) {
+			return fmt.Errorf("xml: EncodeToken of ProcInst containing ?> marker")
+		}
+		p.WriteString("<?")
+		p.WriteString(t.Target)
+		if len(t.Inst) > 0 {
+			p.WriteByte(' ')
+			p.Write(t.Inst)
+		}
+		p.WriteString("?>")
+	case Directive:
+		if bytes.Contains(t, endDirective) {
+			return fmt.Errorf("xml: EncodeToken of Directive containing > marker")
+		}
+		p.WriteString("<!")
+		p.Write(t)
+		p.WriteString(">")
+	}
+	return p.cachedWriteError()
+}
+
+// Flush flushes any buffered XML to the underlying writer.
+// See the EncodeToken documentation for details about when it is necessary.
+func (enc *Encoder) Flush() error {
+	return enc.p.Flush()
 }
 
 type printer struct {
 	*bufio.Writer
+	encoder    *Encoder
 	seq        int
 	indent     string
 	prefix     string
@@ -128,13 +251,15 @@ type printer struct {
 	putNewline bool
 	attrNS     map[string]string // map prefix -> name space
 	attrPrefix map[string]string // map name space -> prefix
+	prefixes   []string
+	tags       []Name
 }
 
 // createAttrPrefix finds the name space prefix attribute to use for the given name space,
-// defining a new prefix if necessary. It returns the prefix and whether it is new.
-func (p *printer) createAttrPrefix(url string) (prefix string, isNew bool) {
-	if prefix = p.attrPrefix[url]; prefix != "" {
-		return prefix, false
+// defining a new prefix if necessary. It returns the prefix.
+func (p *printer) createAttrPrefix(url string) string {
+	if prefix := p.attrPrefix[url]; prefix != "" {
+		return prefix
 	}
 
 	// The "http://www.w3.org/XML/1998/namespace" name space is predefined as "xml"
@@ -142,7 +267,7 @@ func (p *printer) createAttrPrefix(url string) (prefix string, isNew bool) {
 	// (The "http://www.w3.org/2000/xmlns/" name space is also predefined as "xmlns",
 	// but users should not be trying to use that one directly - that's our job.)
 	if url == xmlURL {
-		return "xml", false
+		return "xml"
 	}
 
 	// Need to define a new name space.
@@ -153,7 +278,7 @@ func (p *printer) createAttrPrefix(url string) (prefix string, isNew bool) {
 
 	// Pick a name. We try to use the final element of the path
 	// but fall back to _.
-	prefix = strings.TrimRight(url, "/")
+	prefix := strings.TrimRight(url, "/")
 	if i := strings.LastIndex(prefix, "/"); i >= 0 {
 		prefix = prefix[i+1:]
 	}
@@ -183,7 +308,9 @@ func (p *printer) createAttrPrefix(url string) (prefix string, isNew bool) {
 	EscapeText(p, []byte(url))
 	p.WriteString(`" `)
 
-	return prefix, true
+	p.prefixes = append(p.prefixes, prefix)
+
+	return prefix
 }
 
 // deleteAttrPrefix removes an attribute name space prefix.
@@ -192,9 +319,34 @@ func (p *printer) deleteAttrPrefix(prefix string) {
 	delete(p.attrNS, prefix)
 }
 
+func (p *printer) markPrefix() {
+	p.prefixes = append(p.prefixes, "")
+}
+
+func (p *printer) popPrefix() {
+	for len(p.prefixes) > 0 {
+		prefix := p.prefixes[len(p.prefixes)-1]
+		p.prefixes = p.prefixes[:len(p.prefixes)-1]
+		if prefix == "" {
+			break
+		}
+		p.deleteAttrPrefix(prefix)
+	}
+}
+
+var (
+	marshalerType     = reflect.TypeOf((*Marshaler)(nil)).Elem()
+	marshalerAttrType = reflect.TypeOf((*MarshalerAttr)(nil)).Elem()
+	textMarshalerType = reflect.TypeOf((*encoding.TextMarshaler)(nil)).Elem()
+)
+
 // marshalValue writes one or more XML elements representing val.
 // If val was obtained from a struct field, finfo must have its details.
-func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo) error {
+func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo, startTemplate *StartElement) error {
+	if startTemplate != nil && startTemplate.Name.Local == "" {
+		return fmt.Errorf("xml: EncodeElement of StartElement with missing name")
+	}
+
 	if !val.IsValid() {
 		return nil
 	}
@@ -202,21 +354,45 @@ func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo) error {
 		return nil
 	}
 
+	// Drill into interfaces and pointers.
+	// This can turn into an infinite loop given a cyclic chain,
+	// but it matches the Go 1 behavior.
+	for val.Kind() == reflect.Interface || val.Kind() == reflect.Ptr {
+		if val.IsNil() {
+			return nil
+		}
+		val = val.Elem()
+	}
+
 	kind := val.Kind()
 	typ := val.Type()
 
-	// Drill into pointers/interfaces
-	if kind == reflect.Ptr || kind == reflect.Interface {
-		if val.IsNil() {
-			return nil
+	// Check for marshaler.
+	if val.CanInterface() && typ.Implements(marshalerType) {
+		return p.marshalInterface(val.Interface().(Marshaler), defaultStart(typ, finfo, startTemplate))
+	}
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(marshalerType) {
+			return p.marshalInterface(pv.Interface().(Marshaler), defaultStart(pv.Type(), finfo, startTemplate))
+		}
+	}
+
+	// Check for text marshaler.
+	if val.CanInterface() && typ.Implements(textMarshalerType) {
+		return p.marshalTextInterface(val.Interface().(encoding.TextMarshaler), defaultStart(typ, finfo, startTemplate))
+	}
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(textMarshalerType) {
+			return p.marshalTextInterface(pv.Interface().(encoding.TextMarshaler), defaultStart(pv.Type(), finfo, startTemplate))
 		}
-		return p.marshalValue(val.Elem(), finfo)
 	}
 
 	// Slices and arrays iterate over the elements. They do not have an enclosing tag.
 	if (kind == reflect.Slice || kind == reflect.Array) && typ.Elem().Kind() != reflect.Uint8 {
 		for i, n := 0, val.Len(); i < n; i++ {
-			if err := p.marshalValue(val.Index(i), finfo); err != nil {
+			if err := p.marshalValue(val.Index(i), finfo, startTemplate); err != nil {
 				return err
 			}
 		}
@@ -228,40 +404,34 @@ func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo) error {
 		return err
 	}
 
+	// Create start element.
 	// Precedence for the XML element name is:
+	// 0. startTemplate
 	// 1. XMLName field in underlying struct;
 	// 2. field name/tag in the struct field; and
 	// 3. type name
-	var xmlns, name string
-	if tinfo.xmlname != nil {
+	var start StartElement
+
+	if startTemplate != nil {
+		start.Name = startTemplate.Name
+		start.Attr = append(start.Attr, startTemplate.Attr...)
+	} else if tinfo.xmlname != nil {
 		xmlname := tinfo.xmlname
 		if xmlname.name != "" {
-			xmlns, name = xmlname.xmlns, xmlname.name
+			start.Name.Space, start.Name.Local = xmlname.xmlns, xmlname.name
 		} else if v, ok := xmlname.value(val).Interface().(Name); ok && v.Local != "" {
-			xmlns, name = v.Space, v.Local
+			start.Name = v
 		}
 	}
-	if name == "" && finfo != nil {
-		xmlns, name = finfo.xmlns, finfo.name
+	if start.Name.Local == "" && finfo != nil {
+		start.Name.Space, start.Name.Local = finfo.xmlns, finfo.name
 	}
-	if name == "" {
-		name = typ.Name()
+	if start.Name.Local == "" {
+		name := typ.Name()
 		if name == "" {
 			return &UnsupportedTypeError{typ}
 		}
-	}
-
-	p.writeIndent(1)
-	p.WriteByte('<')
-	p.WriteString(name)
-
-	if xmlns != "" {
-		p.WriteString(` xmlns="`)
-		// TODO: EscapeString, to avoid the allocation.
-		if err := EscapeText(p, []byte(xmlns)); err != nil {
-			return err
-		}
-		p.WriteByte('"')
+		start.Name.Local = name
 	}
 
 	// Attributes
@@ -271,67 +441,243 @@ func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo) error {
 			continue
 		}
 		fv := finfo.value(val)
+		name := Name{Space: finfo.xmlns, Local: finfo.name}
+
 		if finfo.flags&fOmitEmpty != 0 && isEmptyValue(fv) {
 			continue
 		}
-		p.WriteByte(' ')
-		if finfo.xmlns != "" {
-			prefix, created := p.createAttrPrefix(finfo.xmlns)
-			if created {
-				defer p.deleteAttrPrefix(prefix)
+
+		if fv.Kind() == reflect.Interface && fv.IsNil() {
+			continue
+		}
+
+		if fv.CanInterface() && fv.Type().Implements(marshalerAttrType) {
+			attr, err := fv.Interface().(MarshalerAttr).MarshalXMLAttr(name)
+			if err != nil {
+				return err
 			}
-			p.WriteString(prefix)
-			p.WriteByte(':')
+			if attr.Name.Local != "" {
+				start.Attr = append(start.Attr, attr)
+			}
+			continue
 		}
-		p.WriteString(finfo.name)
-		p.WriteString(`="`)
-		if err := p.marshalSimple(fv.Type(), fv); err != nil {
+
+		if fv.CanAddr() {
+			pv := fv.Addr()
+			if pv.CanInterface() && pv.Type().Implements(marshalerAttrType) {
+				attr, err := pv.Interface().(MarshalerAttr).MarshalXMLAttr(name)
+				if err != nil {
+					return err
+				}
+				if attr.Name.Local != "" {
+					start.Attr = append(start.Attr, attr)
+				}
+				continue
+			}
+		}
+
+		if fv.CanInterface() && fv.Type().Implements(textMarshalerType) {
+			text, err := fv.Interface().(encoding.TextMarshaler).MarshalText()
+			if err != nil {
+				return err
+			}
+			start.Attr = append(start.Attr, Attr{name, string(text)})
+			continue
+		}
+
+		if fv.CanAddr() {
+			pv := fv.Addr()
+			if pv.CanInterface() && pv.Type().Implements(textMarshalerType) {
+				text, err := pv.Interface().(encoding.TextMarshaler).MarshalText()
+				if err != nil {
+					return err
+				}
+				start.Attr = append(start.Attr, Attr{name, string(text)})
+				continue
+			}
+		}
+
+		// Dereference or skip nil pointer, interface values.
+		switch fv.Kind() {
+		case reflect.Ptr, reflect.Interface:
+			if fv.IsNil() {
+				continue
+			}
+			fv = fv.Elem()
+		}
+
+		s, b, err := p.marshalSimple(fv.Type(), fv)
+		if err != nil {
 			return err
 		}
-		p.WriteByte('"')
+		if b != nil {
+			s = string(b)
+		}
+		start.Attr = append(start.Attr, Attr{name, s})
+	}
+
+	if err := p.writeStart(&start); err != nil {
+		return err
 	}
-	p.WriteByte('>')
 
 	if val.Kind() == reflect.Struct {
 		err = p.marshalStruct(tinfo, val)
 	} else {
-		err = p.marshalSimple(typ, val)
+		s, b, err1 := p.marshalSimple(typ, val)
+		if err1 != nil {
+			err = err1
+		} else if b != nil {
+			EscapeText(p, b)
+		} else {
+			p.EscapeString(s)
+		}
 	}
 	if err != nil {
 		return err
 	}
 
-	p.writeIndent(-1)
-	p.WriteByte('<')
-	p.WriteByte('/')
-	p.WriteString(name)
-	p.WriteByte('>')
+	if err := p.writeEnd(start.Name); err != nil {
+		return err
+	}
 
 	return p.cachedWriteError()
 }
 
-var timeType = reflect.TypeOf(time.Time{})
+// defaultStart returns the default start element to use,
+// given the reflect type, field info, and start template.
+func defaultStart(typ reflect.Type, finfo *fieldInfo, startTemplate *StartElement) StartElement {
+	var start StartElement
+	// Precedence for the XML element name is as above,
+	// except that we do not look inside structs for the first field.
+	if startTemplate != nil {
+		start.Name = startTemplate.Name
+		start.Attr = append(start.Attr, startTemplate.Attr...)
+	} else if finfo != nil && finfo.name != "" {
+		start.Name.Local = finfo.name
+		start.Name.Space = finfo.xmlns
+	} else if typ.Name() != "" {
+		start.Name.Local = typ.Name()
+	} else {
+		// Must be a pointer to a named type,
+		// since it has the Marshaler methods.
+		start.Name.Local = typ.Elem().Name()
+	}
+	return start
+}
 
-func (p *printer) marshalSimple(typ reflect.Type, val reflect.Value) error {
-	// Normally we don't see structs, but this can happen for an attribute.
-	if val.Type() == timeType {
-		p.WriteString(val.Interface().(time.Time).Format(time.RFC3339Nano))
-		return nil
+// marshalInterface marshals a Marshaler interface value.
+func (p *printer) marshalInterface(val Marshaler, start StartElement) error {
+	// Push a marker onto the tag stack so that MarshalXML
+	// cannot close the XML tags that it did not open.
+	p.tags = append(p.tags, Name{})
+	n := len(p.tags)
+
+	err := val.MarshalXML(p.encoder, start)
+	if err != nil {
+		return err
+	}
+
+	// Make sure MarshalXML closed all its tags. p.tags[n-1] is the mark.
+	if len(p.tags) > n {
+		return fmt.Errorf("xml: %s.MarshalXML wrote invalid XML: <%s> not closed", receiverType(val), p.tags[len(p.tags)-1].Local)
+	}
+	p.tags = p.tags[:n-1]
+	return nil
+}
+
+// marshalTextInterface marshals a TextMarshaler interface value.
+func (p *printer) marshalTextInterface(val encoding.TextMarshaler, start StartElement) error {
+	if err := p.writeStart(&start); err != nil {
+		return err
+	}
+	text, err := val.MarshalText()
+	if err != nil {
+		return err
+	}
+	EscapeText(p, text)
+	return p.writeEnd(start.Name)
+}
+
+// writeStart writes the given start element.
+func (p *printer) writeStart(start *StartElement) error {
+	if start.Name.Local == "" {
+		return fmt.Errorf("xml: start tag with no name")
+	}
+
+	p.tags = append(p.tags, start.Name)
+	p.markPrefix()
+
+	p.writeIndent(1)
+	p.WriteByte('<')
+	p.WriteString(start.Name.Local)
+
+	if start.Name.Space != "" {
+		p.WriteString(` xmlns="`)
+		p.EscapeString(start.Name.Space)
+		p.WriteByte('"')
+	}
+
+	// Attributes
+	for _, attr := range start.Attr {
+		name := attr.Name
+		if name.Local == "" {
+			continue
+		}
+		p.WriteByte(' ')
+		if name.Space != "" {
+			p.WriteString(p.createAttrPrefix(name.Space))
+			p.WriteByte(':')
+		}
+		p.WriteString(name.Local)
+		p.WriteString(`="`)
+		p.EscapeString(attr.Value)
+		p.WriteByte('"')
 	}
+	p.WriteByte('>')
+	return nil
+}
+
+func (p *printer) writeEnd(name Name) error {
+	if name.Local == "" {
+		return fmt.Errorf("xml: end tag with no name")
+	}
+	if len(p.tags) == 0 || p.tags[len(p.tags)-1].Local == "" {
+		return fmt.Errorf("xml: end tag </%s> without start tag", name.Local)
+	}
+	if top := p.tags[len(p.tags)-1]; top != name {
+		if top.Local != name.Local {
+			return fmt.Errorf("xml: end tag </%s> does not match start tag <%s>", name.Local, top.Local)
+		}
+		return fmt.Errorf("xml: end tag </%s> in namespace %s does not match start tag <%s> in namespace %s", name.Local, name.Space, top.Local, top.Space)
+	}
+	p.tags = p.tags[:len(p.tags)-1]
+
+	p.writeIndent(-1)
+	p.WriteByte('<')
+	p.WriteByte('/')
+	p.WriteString(name.Local)
+	p.WriteByte('>')
+	p.popPrefix()
+	return nil
+}
+
+func (p *printer) marshalSimple(typ reflect.Type, val reflect.Value) (string, []byte, error) {
 	switch val.Kind() {
 	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		p.WriteString(strconv.FormatInt(val.Int(), 10))
+		return strconv.FormatInt(val.Int(), 10), nil, nil
 	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-		p.WriteString(strconv.FormatUint(val.Uint(), 10))
+		return strconv.FormatUint(val.Uint(), 10), nil, nil
 	case reflect.Float32, reflect.Float64:
-		p.WriteString(strconv.FormatFloat(val.Float(), 'g', -1, val.Type().Bits()))
+		return strconv.FormatFloat(val.Float(), 'g', -1, val.Type().Bits()), nil, nil
 	case reflect.String:
-		// TODO: Add EscapeString.
-		EscapeText(p, []byte(val.String()))
+		return val.String(), nil, nil
 	case reflect.Bool:
-		p.WriteString(strconv.FormatBool(val.Bool()))
+		return strconv.FormatBool(val.Bool()), nil, nil
 	case reflect.Array:
-		// will be [...]byte
+		if typ.Elem().Kind() != reflect.Uint8 {
+			break
+		}
+		// [...]byte
 		var bytes []byte
 		if val.CanAddr() {
 			bytes = val.Slice(0, val.Len()).Bytes()
@@ -339,32 +685,57 @@ func (p *printer) marshalSimple(typ reflect.Type, val reflect.Value) error {
 			bytes = make([]byte, val.Len())
 			reflect.Copy(reflect.ValueOf(bytes), val)
 		}
-		EscapeText(p, bytes)
+		return "", bytes, nil
 	case reflect.Slice:
-		// will be []byte
-		EscapeText(p, val.Bytes())
-	default:
-		return &UnsupportedTypeError{typ}
+		if typ.Elem().Kind() != reflect.Uint8 {
+			break
+		}
+		// []byte
+		return "", val.Bytes(), nil
 	}
-	return p.cachedWriteError()
+	return "", nil, &UnsupportedTypeError{typ}
 }
 
 var ddBytes = []byte("--")
 
 func (p *printer) marshalStruct(tinfo *typeInfo, val reflect.Value) error {
-	if val.Type() == timeType {
-		_, err := p.WriteString(val.Interface().(time.Time).Format(time.RFC3339Nano))
-		return err
-	}
-	s := parentStack{printer: p}
+	s := parentStack{p: p}
 	for i := range tinfo.fields {
 		finfo := &tinfo.fields[i]
 		if finfo.flags&fAttr != 0 {
 			continue
 		}
 		vf := finfo.value(val)
+
+		// Dereference or skip nil pointer, interface values.
+		switch vf.Kind() {
+		case reflect.Ptr, reflect.Interface:
+			if !vf.IsNil() {
+				vf = vf.Elem()
+			}
+		}
+
 		switch finfo.flags & fMode {
 		case fCharData:
+			if vf.CanInterface() && vf.Type().Implements(textMarshalerType) {
+				data, err := vf.Interface().(encoding.TextMarshaler).MarshalText()
+				if err != nil {
+					return err
+				}
+				Escape(p, data)
+				continue
+			}
+			if vf.CanAddr() {
+				pv := vf.Addr()
+				if pv.CanInterface() && pv.Type().Implements(textMarshalerType) {
+					data, err := pv.Interface().(encoding.TextMarshaler).MarshalText()
+					if err != nil {
+						return err
+					}
+					Escape(p, data)
+					continue
+				}
+			}
 			var scratch [64]byte
 			switch vf.Kind() {
 			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
@@ -385,10 +756,6 @@ func (p *printer) marshalStruct(tinfo *typeInfo, val reflect.Value) error {
 						return err
 					}
 				}
-			case reflect.Struct:
-				if vf.Type() == timeType {
-					Escape(p, []byte(vf.Interface().(time.Time).Format(time.RFC3339Nano)))
-				}
 			}
 			continue
 
@@ -444,14 +811,18 @@ func (p *printer) marshalStruct(tinfo *typeInfo, val reflect.Value) error {
 			}
 
 		case fElement, fElement | fAny:
-			s.trim(finfo.parents)
+			if err := s.trim(finfo.parents); err != nil {
+				return err
+			}
 			if len(finfo.parents) > len(s.stack) {
 				if vf.Kind() != reflect.Ptr && vf.Kind() != reflect.Interface || !vf.IsNil() {
-					s.push(finfo.parents[len(s.stack):])
+					if err := s.push(finfo.parents[len(s.stack):]); err != nil {
+						return err
+					}
 				}
 			}
 		}
-		if err := p.marshalValue(vf, finfo); err != nil {
+		if err := p.marshalValue(vf, finfo, nil); err != nil {
 			return err
 		}
 	}
@@ -497,14 +868,14 @@ func (p *printer) writeIndent(depthDelta int) {
 }
 
 type parentStack struct {
-	*printer
+	p     *printer
 	stack []string
 }
 
 // trim updates the XML context to match the longest common prefix of the stack
 // and the given parents.  A closing tag will be written for every parent
 // popped.  Passing a zero slice or nil will close all the elements.
-func (s *parentStack) trim(parents []string) {
+func (s *parentStack) trim(parents []string) error {
 	split := 0
 	for ; split < len(parents) && split < len(s.stack); split++ {
 		if parents[split] != s.stack[split] {
@@ -512,23 +883,23 @@ func (s *parentStack) trim(parents []string) {
 		}
 	}
 	for i := len(s.stack) - 1; i >= split; i-- {
-		s.writeIndent(-1)
-		s.WriteString("</")
-		s.WriteString(s.stack[i])
-		s.WriteByte('>')
+		if err := s.p.writeEnd(Name{Local: s.stack[i]}); err != nil {
+			return err
+		}
 	}
 	s.stack = parents[:split]
+	return nil
 }
 
 // push adds parent elements to the stack and writes open tags.
-func (s *parentStack) push(parents []string) {
+func (s *parentStack) push(parents []string) error {
 	for i := 0; i < len(parents); i++ {
-		s.writeIndent(1)
-		s.WriteByte('<')
-		s.WriteString(parents[i])
-		s.WriteByte('>')
+		if err := s.p.writeStart(&StartElement{Name: Name{Local: parents[i]}}); err != nil {
+			return err
+		}
 	}
 	s.stack = append(s.stack, parents...)
+	return nil
 }
 
 // A MarshalXMLError is returned when Marshal encounters a type
diff --git a/libgo/go/encoding/xml/marshal_test.go b/libgo/go/encoding/xml/marshal_test.go
index ca14a1e..d34118a 100644
--- a/libgo/go/encoding/xml/marshal_test.go
+++ b/libgo/go/encoding/xml/marshal_test.go
@@ -276,6 +276,54 @@ type Strings struct {
 	X []string `xml:"A>B,omitempty"`
 }
 
+type PointerFieldsTest struct {
+	XMLName  Name    `xml:"dummy"`
+	Name     *string `xml:"name,attr"`
+	Age      *uint   `xml:"age,attr"`
+	Empty    *string `xml:"empty,attr"`
+	Contents *string `xml:",chardata"`
+}
+
+type ChardataEmptyTest struct {
+	XMLName  Name    `xml:"test"`
+	Contents *string `xml:",chardata"`
+}
+
+type MyMarshalerTest struct {
+}
+
+var _ Marshaler = (*MyMarshalerTest)(nil)
+
+func (m *MyMarshalerTest) MarshalXML(e *Encoder, start StartElement) error {
+	e.EncodeToken(start)
+	e.EncodeToken(CharData([]byte("hello world")))
+	e.EncodeToken(EndElement{start.Name})
+	return nil
+}
+
+type MyMarshalerAttrTest struct {
+}
+
+var _ MarshalerAttr = (*MyMarshalerAttrTest)(nil)
+
+func (m *MyMarshalerAttrTest) MarshalXMLAttr(name Name) (Attr, error) {
+	return Attr{name, "hello world"}, nil
+}
+
+type MarshalerStruct struct {
+	Foo MyMarshalerAttrTest `xml:",attr"`
+}
+
+func ifaceptr(x interface{}) interface{} {
+	return &x
+}
+
+var (
+	nameAttr     = "Sarah"
+	ageAttr      = uint(12)
+	contentsAttr = "lorem ipsum"
+)
+
 // Unless explicitly stated as such (or *Plain), all of the
 // tests below are two-way tests. When introducing new tests,
 // please try to make them two-way as well to ensure that
@@ -312,6 +360,7 @@ var marshalTests = []struct {
 	{Value: &Plain{NamedType("potato")}, ExpectXML: `<Plain><V>potato</V></Plain>`},
 	{Value: &Plain{[]int{1, 2, 3}}, ExpectXML: `<Plain><V>1</V><V>2</V><V>3</V></Plain>`},
 	{Value: &Plain{[3]int{1, 2, 3}}, ExpectXML: `<Plain><V>1</V><V>2</V><V>3</V></Plain>`},
+	{Value: ifaceptr(true), MarshalOnly: true, ExpectXML: `<bool>true</bool>`},
 
 	// Test time.
 	{
@@ -673,6 +722,20 @@ var marshalTests = []struct {
 		ExpectXML: `<OmitAttrTest></OmitAttrTest>`,
 	},
 
+	// pointer fields
+	{
+		Value:       &PointerFieldsTest{Name: &nameAttr, Age: &ageAttr, Contents: &contentsAttr},
+		ExpectXML:   `<dummy name="Sarah" age="12">lorem ipsum</dummy>`,
+		MarshalOnly: true,
+	},
+
+	// empty chardata pointer field
+	{
+		Value:       &ChardataEmptyTest{},
+		ExpectXML:   `<test></test>`,
+		MarshalOnly: true,
+	},
+
 	// omitempty on fields
 	{
 		Value: &OmitFieldTest{
@@ -811,6 +874,15 @@ var marshalTests = []struct {
 		ExpectXML: `<Strings><A></A></Strings>`,
 		Value:     &Strings{},
 	},
+	// Custom marshalers.
+	{
+		ExpectXML: `<MyMarshalerTest>hello world</MyMarshalerTest>`,
+		Value:     &MyMarshalerTest{},
+	},
+	{
+		ExpectXML: `<MarshalerStruct Foo="hello world"></MarshalerStruct>`,
+		Value:     &MarshalerStruct{},
+	},
 }
 
 func TestMarshal(t *testing.T) {
@@ -837,6 +909,10 @@ type AttrParent struct {
 	X string `xml:"X>Y,attr"`
 }
 
+type BadAttr struct {
+	Name []string `xml:"name,attr"`
+}
+
 var marshalErrorTests = []struct {
 	Value interface{}
 	Err   string
@@ -869,6 +945,10 @@ var marshalErrorTests = []struct {
 		Value: &AttrParent{},
 		Err:   `xml: X>Y chain not valid with attr flag`,
 	},
+	{
+		Value: BadAttr{[]string{"X", "Y"}},
+		Err:   `xml: unsupported type: []string`,
+	},
 }
 
 var marshalIndentTests = []struct {
@@ -1009,6 +1089,23 @@ func TestMarshalWriteIOErrors(t *testing.T) {
 	}
 }
 
+func TestMarshalFlush(t *testing.T) {
+	var buf bytes.Buffer
+	enc := NewEncoder(&buf)
+	if err := enc.EncodeToken(CharData("hello world")); err != nil {
+		t.Fatalf("enc.EncodeToken: %v", err)
+	}
+	if buf.Len() > 0 {
+		t.Fatalf("enc.EncodeToken caused actual write: %q", buf.Bytes())
+	}
+	if err := enc.Flush(); err != nil {
+		t.Fatalf("enc.Flush: %v", err)
+	}
+	if buf.String() != "hello world" {
+		t.Fatalf("after enc.Flush, buf.String() = %q, want %q", buf.String(), "hello world")
+	}
+}
+
 func BenchmarkMarshal(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		Marshal(atomValue)
@@ -1021,3 +1118,34 @@ func BenchmarkUnmarshal(b *testing.B) {
 		Unmarshal(xml, &Feed{})
 	}
 }
+
+// golang.org/issue/6556
+func TestStructPointerMarshal(t *testing.T) {
+	type A struct {
+		XMLName string `xml:"a"`
+		B       []interface{}
+	}
+	type C struct {
+		XMLName Name
+		Value   string `xml:"value"`
+	}
+
+	a := new(A)
+	a.B = append(a.B, &C{
+		XMLName: Name{Local: "c"},
+		Value:   "x",
+	})
+
+	b, err := Marshal(a)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if x := string(b); x != "<a><c><value>x</value></c></a>" {
+		t.Fatal(x)
+	}
+	var v A
+	err = Unmarshal(b, &v)
+	if err != nil {
+		t.Fatal(err)
+	}
+}
diff --git a/libgo/go/encoding/xml/read.go b/libgo/go/encoding/xml/read.go
index a7a2a96..da7ad3b 100644
--- a/libgo/go/encoding/xml/read.go
+++ b/libgo/go/encoding/xml/read.go
@@ -6,11 +6,12 @@ package xml
 
 import (
 	"bytes"
+	"encoding"
 	"errors"
+	"fmt"
 	"reflect"
 	"strconv"
 	"strings"
-	"time"
 )
 
 // BUG(rsc): Mapping between XML elements and data structures is inherently flawed:
@@ -57,7 +58,7 @@ import (
 //      If there is no such field, the character data is discarded.
 //
 //   * If the XML element contains comments, they are accumulated in
-//      the first struct field that has tag ",comments".  The struct
+//      the first struct field that has tag ",comment".  The struct
 //      field may have type []byte or string.  If there is no such
 //      field, the comments are discarded.
 //
@@ -137,6 +138,136 @@ type UnmarshalError string
 
 func (e UnmarshalError) Error() string { return string(e) }
 
+// Unmarshaler is the interface implemented by objects that can unmarshal
+// an XML element description of themselves.
+//
+// UnmarshalXML decodes a single XML element
+// beginning with the given start element.
+// If it returns an error, the outer call to Unmarshal stops and
+// returns that error.
+// UnmarshalXML must consume exactly one XML element.
+// One common implementation strategy is to unmarshal into
+// a separate value with a layout matching the expected XML
+// using d.DecodeElement,  and then to copy the data from
+// that value into the receiver.
+// Another common strategy is to use d.Token to process the
+// XML object one token at a time.
+// UnmarshalXML may not use d.RawToken.
+type Unmarshaler interface {
+	UnmarshalXML(d *Decoder, start StartElement) error
+}
+
+// UnmarshalerAttr is the interface implemented by objects that can unmarshal
+// an XML attribute description of themselves.
+//
+// UnmarshalXMLAttr decodes a single XML attribute.
+// If it returns an error, the outer call to Unmarshal stops and
+// returns that error.
+// UnmarshalXMLAttr is used only for struct fields with the
+// "attr" option in the field tag.
+type UnmarshalerAttr interface {
+	UnmarshalXMLAttr(attr Attr) error
+}
+
+// receiverType returns the receiver type to use in an expression like "%s.MethodName".
+func receiverType(val interface{}) string {
+	t := reflect.TypeOf(val)
+	if t.Name() != "" {
+		return t.String()
+	}
+	return "(" + t.String() + ")"
+}
+
+// unmarshalInterface unmarshals a single XML element into val.
+// start is the opening tag of the element.
+func (p *Decoder) unmarshalInterface(val Unmarshaler, start *StartElement) error {
+	// Record that decoder must stop at end tag corresponding to start.
+	p.pushEOF()
+
+	p.unmarshalDepth++
+	err := val.UnmarshalXML(p, *start)
+	p.unmarshalDepth--
+	if err != nil {
+		p.popEOF()
+		return err
+	}
+
+	if !p.popEOF() {
+		return fmt.Errorf("xml: %s.UnmarshalXML did not consume entire <%s> element", receiverType(val), start.Name.Local)
+	}
+
+	return nil
+}
+
+// unmarshalTextInterface unmarshals a single XML element into val.
+// The chardata contained in the element (but not its children)
+// is passed to the text unmarshaler.
+func (p *Decoder) unmarshalTextInterface(val encoding.TextUnmarshaler, start *StartElement) error {
+	var buf []byte
+	depth := 1
+	for depth > 0 {
+		t, err := p.Token()
+		if err != nil {
+			return err
+		}
+		switch t := t.(type) {
+		case CharData:
+			if depth == 1 {
+				buf = append(buf, t...)
+			}
+		case StartElement:
+			depth++
+		case EndElement:
+			depth--
+		}
+	}
+	return val.UnmarshalText(buf)
+}
+
+// unmarshalAttr unmarshals a single XML attribute into val.
+func (p *Decoder) unmarshalAttr(val reflect.Value, attr Attr) error {
+	if val.Kind() == reflect.Ptr {
+		if val.IsNil() {
+			val.Set(reflect.New(val.Type().Elem()))
+		}
+		val = val.Elem()
+	}
+
+	if val.CanInterface() && val.Type().Implements(unmarshalerAttrType) {
+		// This is an unmarshaler with a non-pointer receiver,
+		// so it's likely to be incorrect, but we do what we're told.
+		return val.Interface().(UnmarshalerAttr).UnmarshalXMLAttr(attr)
+	}
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(unmarshalerAttrType) {
+			return pv.Interface().(UnmarshalerAttr).UnmarshalXMLAttr(attr)
+		}
+	}
+
+	// Not an UnmarshalerAttr; try encoding.TextUnmarshaler.
+	if val.CanInterface() && val.Type().Implements(textUnmarshalerType) {
+		// This is an unmarshaler with a non-pointer receiver,
+		// so it's likely to be incorrect, but we do what we're told.
+		return val.Interface().(encoding.TextUnmarshaler).UnmarshalText([]byte(attr.Value))
+	}
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+			return pv.Interface().(encoding.TextUnmarshaler).UnmarshalText([]byte(attr.Value))
+		}
+	}
+
+	copyValue(val, []byte(attr.Value))
+	return nil
+}
+
+var (
+	unmarshalerType     = reflect.TypeOf((*Unmarshaler)(nil)).Elem()
+	unmarshalerAttrType = reflect.TypeOf((*UnmarshalerAttr)(nil)).Elem()
+	textUnmarshalerType = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
+)
+
 // Unmarshal a single XML element into val.
 func (p *Decoder) unmarshal(val reflect.Value, start *StartElement) error {
 	// Find start element if we need it.
@@ -153,11 +284,35 @@ func (p *Decoder) unmarshal(val reflect.Value, start *StartElement) error {
 		}
 	}
 
-	if pv := val; pv.Kind() == reflect.Ptr {
-		if pv.IsNil() {
-			pv.Set(reflect.New(pv.Type().Elem()))
+	if val.Kind() == reflect.Ptr {
+		if val.IsNil() {
+			val.Set(reflect.New(val.Type().Elem()))
+		}
+		val = val.Elem()
+	}
+
+	if val.CanInterface() && val.Type().Implements(unmarshalerType) {
+		// This is an unmarshaler with a non-pointer receiver,
+		// so it's likely to be incorrect, but we do what we're told.
+		return p.unmarshalInterface(val.Interface().(Unmarshaler), start)
+	}
+
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(unmarshalerType) {
+			return p.unmarshalInterface(pv.Interface().(Unmarshaler), start)
+		}
+	}
+
+	if val.CanInterface() && val.Type().Implements(textUnmarshalerType) {
+		return p.unmarshalTextInterface(val.Interface().(encoding.TextUnmarshaler), start)
+	}
+
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+			return p.unmarshalTextInterface(pv.Interface().(encoding.TextUnmarshaler), start)
 		}
-		val = pv.Elem()
 	}
 
 	var (
@@ -222,10 +377,6 @@ func (p *Decoder) unmarshal(val reflect.Value, start *StartElement) error {
 			v.Set(reflect.ValueOf(start.Name))
 			break
 		}
-		if typ == timeType {
-			saveData = v
-			break
-		}
 
 		sv = v
 		tinfo, err = getTypeInfo(typ)
@@ -264,7 +415,9 @@ func (p *Decoder) unmarshal(val reflect.Value, start *StartElement) error {
 				// Look for attribute.
 				for _, a := range start.Attr {
 					if a.Name.Local == finfo.name && (finfo.xmlns == "" || finfo.xmlns == a.Name.Space) {
-						copyValue(strv, []byte(a.Value))
+						if err := p.unmarshalAttr(strv, a); err != nil {
+							return err
+						}
 						break
 					}
 				}
@@ -352,6 +505,23 @@ Loop:
 		}
 	}
 
+	if saveData.IsValid() && saveData.CanInterface() && saveData.Type().Implements(textUnmarshalerType) {
+		if err := saveData.Interface().(encoding.TextUnmarshaler).UnmarshalText(data); err != nil {
+			return err
+		}
+		saveData = reflect.Value{}
+	}
+
+	if saveData.IsValid() && saveData.CanAddr() {
+		pv := saveData.Addr()
+		if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+			if err := pv.Interface().(encoding.TextUnmarshaler).UnmarshalText(data); err != nil {
+				return err
+			}
+			saveData = reflect.Value{}
+		}
+	}
+
 	if err := copyValue(saveData, data); err != nil {
 		return err
 	}
@@ -374,6 +544,8 @@ Loop:
 }
 
 func copyValue(dst reflect.Value, src []byte) (err error) {
+	dst0 := dst
+
 	if dst.Kind() == reflect.Ptr {
 		if dst.IsNil() {
 			dst.Set(reflect.New(dst.Type().Elem()))
@@ -384,9 +556,9 @@ func copyValue(dst reflect.Value, src []byte) (err error) {
 	// Save accumulated data.
 	switch dst.Kind() {
 	case reflect.Invalid:
-		// Probably a commendst.
+		// Probably a comment.
 	default:
-		return errors.New("cannot happen: unknown type " + dst.Type().String())
+		return errors.New("cannot unmarshal into " + dst0.Type().String())
 	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
 		itmp, err := strconv.ParseInt(string(src), 10, dst.Type().Bits())
 		if err != nil {
@@ -419,14 +591,6 @@ func copyValue(dst reflect.Value, src []byte) (err error) {
 			src = []byte{}
 		}
 		dst.SetBytes(src)
-	case reflect.Struct:
-		if dst.Type() == timeType {
-			tv, err := time.Parse(time.RFC3339, string(src))
-			if err != nil {
-				return err
-			}
-			dst.Set(reflect.ValueOf(tv))
-		}
 	}
 	return nil
 }
diff --git a/libgo/go/encoding/xml/read_test.go b/libgo/go/encoding/xml/read_test.go
index 7d28c5d..1404c90 100644
--- a/libgo/go/encoding/xml/read_test.go
+++ b/libgo/go/encoding/xml/read_test.go
@@ -5,6 +5,7 @@
 package xml
 
 import (
+	"io"
 	"reflect"
 	"strings"
 	"testing"
@@ -621,3 +622,66 @@ func TestMarshalNSAttr(t *testing.T) {
 		t.Errorf("Unmarshal = %q, want %q", dst, src)
 	}
 }
+
+type MyCharData struct {
+	body string
+}
+
+func (m *MyCharData) UnmarshalXML(d *Decoder, start StartElement) error {
+	for {
+		t, err := d.Token()
+		if err == io.EOF { // found end of element
+			break
+		}
+		if err != nil {
+			return err
+		}
+		if char, ok := t.(CharData); ok {
+			m.body += string(char)
+		}
+	}
+	return nil
+}
+
+var _ Unmarshaler = (*MyCharData)(nil)
+
+func (m *MyCharData) UnmarshalXMLAttr(attr Attr) error {
+	panic("must not call")
+}
+
+type MyAttr struct {
+	attr string
+}
+
+func (m *MyAttr) UnmarshalXMLAttr(attr Attr) error {
+	m.attr = attr.Value
+	return nil
+}
+
+var _ UnmarshalerAttr = (*MyAttr)(nil)
+
+type MyStruct struct {
+	Data *MyCharData
+	Attr *MyAttr `xml:",attr"`
+
+	Data2 MyCharData
+	Attr2 MyAttr `xml:",attr"`
+}
+
+func TestUnmarshaler(t *testing.T) {
+	xml := `<?xml version="1.0" encoding="utf-8"?>
+		<MyStruct Attr="attr1" Attr2="attr2">
+		<Data>hello <!-- comment -->world</Data>
+		<Data2>howdy <!-- comment -->world</Data2>
+		</MyStruct>
+	`
+
+	var m MyStruct
+	if err := Unmarshal([]byte(xml), &m); err != nil {
+		t.Fatal(err)
+	}
+
+	if m.Data == nil || m.Attr == nil || m.Data.body != "hello world" || m.Attr.attr != "attr1" || m.Data2.body != "howdy world" || m.Attr2.attr != "attr2" {
+		t.Errorf("m=%#+v\n", m)
+	}
+}
diff --git a/libgo/go/encoding/xml/xml.go b/libgo/go/encoding/xml/xml.go
index 021f7e4..5b9d670 100644
--- a/libgo/go/encoding/xml/xml.go
+++ b/libgo/go/encoding/xml/xml.go
@@ -16,6 +16,7 @@ package xml
 import (
 	"bufio"
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
 	"strconv"
@@ -66,6 +67,11 @@ func (e StartElement) Copy() StartElement {
 	return e
 }
 
+// End returns the corresponding XML end element.
+func (e StartElement) End() EndElement {
+	return EndElement{e.Name}
+}
+
 // An EndElement represents an XML end element.
 type EndElement struct {
 	Name Name
@@ -144,6 +150,10 @@ type Decoder struct {
 	//	d.Entity = HTMLEntity
 	//
 	// creates a parser that can handle typical HTML.
+	//
+	// Strict mode does not enforce the requirements of the XML name spaces TR.
+	// In particular it does not reject name space tags using undefined prefixes.
+	// Such tags are recorded with the unknown prefix as the name space URL.
 	Strict bool
 
 	// When Strict == false, AutoClose indicates a set of elements to
@@ -174,18 +184,19 @@ type Decoder struct {
 	// the attribute xmlns="DefaultSpace".
 	DefaultSpace string
 
-	r         io.ByteReader
-	buf       bytes.Buffer
-	saved     *bytes.Buffer
-	stk       *stack
-	free      *stack
-	needClose bool
-	toClose   Name
-	nextToken Token
-	nextByte  int
-	ns        map[string]string
-	err       error
-	line      int
+	r              io.ByteReader
+	buf            bytes.Buffer
+	saved          *bytes.Buffer
+	stk            *stack
+	free           *stack
+	needClose      bool
+	toClose        Name
+	nextToken      Token
+	nextByte       int
+	ns             map[string]string
+	err            error
+	line           int
+	unmarshalDepth int
 }
 
 // NewDecoder creates a new XML parser reading from r.
@@ -223,10 +234,14 @@ func NewDecoder(r io.Reader) *Decoder {
 // If Token encounters an unrecognized name space prefix,
 // it uses the prefix as the Space rather than report an error.
 func (d *Decoder) Token() (t Token, err error) {
+	if d.stk != nil && d.stk.kind == stkEOF {
+		err = io.EOF
+		return
+	}
 	if d.nextToken != nil {
 		t = d.nextToken
 		d.nextToken = nil
-	} else if t, err = d.RawToken(); err != nil {
+	} else if t, err = d.rawToken(); err != nil {
 		return
 	}
 
@@ -322,6 +337,7 @@ type stack struct {
 const (
 	stkStart = iota
 	stkNs
+	stkEOF
 )
 
 func (d *Decoder) push(kind int) *stack {
@@ -347,6 +363,43 @@ func (d *Decoder) pop() *stack {
 	return s
 }
 
+// Record that after the current element is finished
+// (that element is already pushed on the stack)
+// Token should return EOF until popEOF is called.
+func (d *Decoder) pushEOF() {
+	// Walk down stack to find Start.
+	// It might not be the top, because there might be stkNs
+	// entries above it.
+	start := d.stk
+	for start.kind != stkStart {
+		start = start.next
+	}
+	// The stkNs entries below a start are associated with that
+	// element too; skip over them.
+	for start.next != nil && start.next.kind == stkNs {
+		start = start.next
+	}
+	s := d.free
+	if s != nil {
+		d.free = s.next
+	} else {
+		s = new(stack)
+	}
+	s.kind = stkEOF
+	s.next = start.next
+	start.next = s
+}
+
+// Undo a pushEOF.
+// The element must have been finished, so the EOF should be at the top of the stack.
+func (d *Decoder) popEOF() bool {
+	if d.stk == nil || d.stk.kind != stkEOF {
+		return false
+	}
+	d.pop()
+	return true
+}
+
 // Record that we are starting an element with the given name.
 func (d *Decoder) pushElement(name Name) {
 	s := d.push(stkStart)
@@ -395,9 +448,9 @@ func (d *Decoder) popElement(t *EndElement) bool {
 		return false
 	}
 
-	// Pop stack until a Start is on the top, undoing the
+	// Pop stack until a Start or EOF is on the top, undoing the
 	// translations that were associated with the element we just closed.
-	for d.stk != nil && d.stk.kind != stkStart {
+	for d.stk != nil && d.stk.kind != stkStart && d.stk.kind != stkEOF {
 		s := d.pop()
 		if s.ok {
 			d.ns[s.name.Local] = s.name.Space
@@ -429,10 +482,19 @@ func (d *Decoder) autoClose(t Token) (Token, bool) {
 	return nil, false
 }
 
+var errRawToken = errors.New("xml: cannot use RawToken from UnmarshalXML method")
+
 // RawToken is like Token but does not verify that
 // start and end elements match and does not translate
 // name space prefixes to their corresponding URLs.
 func (d *Decoder) RawToken() (Token, error) {
+	if d.unmarshalDepth > 0 {
+		return nil, errRawToken
+	}
+	return d.rawToken()
+}
+
+func (d *Decoder) rawToken() (Token, error) {
 	if d.err != nil {
 		return nil, d.err
 	}
@@ -484,8 +546,7 @@ func (d *Decoder) RawToken() (Token, error) {
 
 	case '?':
 		// <?: Processing instruction.
-		// TODO(rsc): Should parse the <?xml declaration to make sure
-		// the version is 1.0 and the encoding is UTF-8.
+		// TODO(rsc): Should parse the <?xml declaration to make sure the version is 1.0.
 		var target string
 		if target, ok = d.name(); !ok {
 			if d.err == nil {
@@ -1112,6 +1173,30 @@ func isName(s []byte) bool {
 	return true
 }
 
+func isNameString(s string) bool {
+	if len(s) == 0 {
+		return false
+	}
+	c, n := utf8.DecodeRuneInString(s)
+	if c == utf8.RuneError && n == 1 {
+		return false
+	}
+	if !unicode.Is(first, c) {
+		return false
+	}
+	for n < len(s) {
+		s = s[n:]
+		c, n = utf8.DecodeRuneInString(s)
+		if c == utf8.RuneError && n == 1 {
+			return false
+		}
+		if !unicode.Is(first, c) && !unicode.Is(second, c) {
+			return false
+		}
+	}
+	return true
+}
+
 // These tables were generated by cut and paste from Appendix B of
 // the XML spec at http://www.xml.com/axml/testaxml.htm
 // and then reformatting.  First corresponds to (Letter | '_' | ':')
@@ -1758,7 +1843,7 @@ func EscapeText(w io.Writer, s []byte) error {
 		case '\r':
 			esc = esc_cr
 		default:
-			if !isInCharacterRange(r) {
+			if !isInCharacterRange(r) || (r == 0xFFFD && width == 1) {
 				esc = esc_fffd
 				break
 			}
@@ -1778,6 +1863,45 @@ func EscapeText(w io.Writer, s []byte) error {
 	return nil
 }
 
+// EscapeString writes to p the properly escaped XML equivalent
+// of the plain text data s.
+func (p *printer) EscapeString(s string) {
+	var esc []byte
+	last := 0
+	for i := 0; i < len(s); {
+		r, width := utf8.DecodeRuneInString(s[i:])
+		i += width
+		switch r {
+		case '"':
+			esc = esc_quot
+		case '\'':
+			esc = esc_apos
+		case '&':
+			esc = esc_amp
+		case '<':
+			esc = esc_lt
+		case '>':
+			esc = esc_gt
+		case '\t':
+			esc = esc_tab
+		case '\n':
+			esc = esc_nl
+		case '\r':
+			esc = esc_cr
+		default:
+			if !isInCharacterRange(r) || (r == 0xFFFD && width == 1) {
+				esc = esc_fffd
+				break
+			}
+			continue
+		}
+		p.WriteString(s[last : i-width])
+		p.Write(esc)
+		last = i
+	}
+	p.WriteString(s[last:])
+}
+
 // Escape is like EscapeText but omits the error return value.
 // It is provided for backwards compatibility with Go 1.0.
 // Code targeting Go 1.1 or later should use EscapeText.
diff --git a/libgo/go/encoding/xml/xml_test.go b/libgo/go/encoding/xml/xml_test.go
index eeedbe5..7723ab1 100644
--- a/libgo/go/encoding/xml/xml_test.go
+++ b/libgo/go/encoding/xml/xml_test.go
@@ -11,6 +11,7 @@ import (
 	"reflect"
 	"strings"
 	"testing"
+	"unicode/utf8"
 )
 
 const testInput = `
@@ -246,10 +247,8 @@ func (d *downCaser) Read(p []byte) (int, error) {
 }
 
 func TestRawTokenAltEncoding(t *testing.T) {
-	sawEncoding := ""
 	d := NewDecoder(strings.NewReader(testInputAltEncoding))
 	d.CharsetReader = func(charset string, input io.Reader) (io.Reader, error) {
-		sawEncoding = charset
 		if charset != "x-testing-uppercase" {
 			t.Fatalf("unexpected charset %q", charset)
 		}
@@ -714,3 +713,14 @@ func TestEscapeTextInvalidChar(t *testing.T) {
 		t.Errorf("have %v, want %v", text, expected)
 	}
 }
+
+func TestIssue5880(t *testing.T) {
+	type T []byte
+	data, err := Marshal(T{192, 168, 0, 1})
+	if err != nil {
+		t.Errorf("Marshal error: %v", err)
+	}
+	if !utf8.Valid(data) {
+		t.Errorf("Marshal generated invalid UTF-8: %x", data)
+	}
+}