libgo: Update to weekly.2011-11-01.

From-SVN: r181938

169 files changed, 2243 insertions, 1608 deletions

diff --git a/gcc/go/gofrontend/types.cc b/gcc/go/gofrontend/types.cc
index 74d9765..f63d169 100644
--- a/gcc/go/gofrontend/types.cc
+++ b/gcc/go/gofrontend/types.cc
@@ -5876,13 +5876,13 @@ Interface_type::do_reflection(Gogo* gogo, std::string* ret) const
   ret->append("interface {");
   if (this->methods_ != NULL)
     {
+      ret->push_back(' ');
       for (Typed_identifier_list::const_iterator p = this->methods_->begin();
 	   p != this->methods_->end();
 	   ++p)
 	{
 	  if (p != this->methods_->begin())
-	    ret->append(";");
-	  ret->push_back(' ');
+	    ret->append("; ");
 	  if (!Gogo::is_hidden_name(p->name()))
 	    ret->append(p->name());
 	  else
@@ -5898,8 +5898,9 @@ Interface_type::do_reflection(Gogo* gogo, std::string* ret) const
 	  sub = sub.substr(4);
 	  ret->append(sub);
 	}
+      ret->push_back(' ');
     }
-  ret->append(" }");
+  ret->append("}");
 }
 
 // Mangled name.
diff --git a/libgo/config.h.in b/libgo/config.h.in
index 0c1283c..f30af59 100644
--- a/libgo/config.h.in
+++ b/libgo/config.h.in
@@ -33,18 +33,12 @@
 /* Define to 1 if the system has the type `off64_t'. */
 #undef HAVE_OFF64_T
 
-/* Define to 1 if you have the `random' function. */
-#undef HAVE_RANDOM
-
 /* Define to 1 if you have the `sem_timedwait' function. */
 #undef HAVE_SEM_TIMEDWAIT
 
 /* Define to 1 if you have the `setenv' function. */
 #undef HAVE_SETENV
 
-/* Define to 1 if you have the `srandom' function. */
-#undef HAVE_SRANDOM
-
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H
 
diff --git a/libgo/configure b/libgo/configure
index e9f536a..2e99887 100755
--- a/libgo/configure
+++ b/libgo/configure
@@ -14529,7 +14529,7 @@ else
 fi
 
 
-for ac_func in srandom random strerror_r strsignal wait4 mincore setenv
+for ac_func in strerror_r strsignal wait4 mincore setenv
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
diff --git a/libgo/configure.ac b/libgo/configure.ac
index 576d1a6..62d4c95 100644
--- a/libgo/configure.ac
+++ b/libgo/configure.ac
@@ -452,7 +452,7 @@ AC_CHECK_HEADERS([linux/filter.h linux/netlink.h linux/rtnetlink.h], [], [],
 
 AM_CONDITIONAL(HAVE_SYS_MMAN_H, test "$ac_cv_header_sys_mman_h" = yes)
 
-AC_CHECK_FUNCS(srandom random strerror_r strsignal wait4 mincore setenv)
+AC_CHECK_FUNCS(strerror_r strsignal wait4 mincore setenv)
 AM_CONDITIONAL(HAVE_STRERROR_R, test "$ac_cv_func_strerror_r" = yes)
 AM_CONDITIONAL(HAVE_WAIT4, test "$ac_cv_func_wait4" = yes)
 
diff --git a/libgo/go/archive/zip/struct.go b/libgo/go/archive/zip/struct.go
index a32de5a..4f9f599 100644
--- a/libgo/go/archive/zip/struct.go
+++ b/libgo/go/archive/zip/struct.go
@@ -60,10 +60,10 @@ type directoryEnd struct {
 	comment            string
 }
 
-func recoverError(err *os.Error) {
+func recoverError(errp *os.Error) {
 	if e := recover(); e != nil {
-		if osErr, ok := e.(os.Error); ok {
-			*err = osErr
+		if err, ok := e.(os.Error); ok {
+			*errp = err
 			return
 		}
 		panic(e)
diff --git a/libgo/go/big/int.go b/libgo/go/big/int.go
index b0dde1e..db13d20 100644
--- a/libgo/go/big/int.go
+++ b/libgo/go/big/int.go
@@ -302,7 +302,7 @@ func (x *Int) String() string {
 	return x.abs.decimalString()
 }
 
-func charset(ch int) string {
+func charset(ch rune) string {
 	switch ch {
 	case 'b':
 		return lowercaseDigits[0:2]
@@ -339,7 +339,7 @@ func writeMultiple(s fmt.State, text string, count int) {
 // output field width, space or zero padding, and left or
 // right justification.
 //
-func (x *Int) Format(s fmt.State, ch int) {
+func (x *Int) Format(s fmt.State, ch rune) {
 	cs := charset(ch)
 
 	// special cases
@@ -460,7 +460,7 @@ func (z *Int) scan(r io.RuneScanner, base int) (*Int, int, os.Error) {
 // Scan is a support routine for fmt.Scanner; it sets z to the value of
 // the scanned number. It accepts the formats 'b' (binary), 'o' (octal),
 // 'd' (decimal), 'x' (lowercase hexadecimal), and 'X' (uppercase hexadecimal).
-func (z *Int) Scan(s fmt.ScanState, ch int) os.Error {
+func (z *Int) Scan(s fmt.ScanState, ch rune) os.Error {
 	s.SkipSpace() // skip leading space characters
 	base := 0
 	switch ch {
diff --git a/libgo/go/big/int_test.go b/libgo/go/big/int_test.go
index fde19c2..d66bb5f 100644
--- a/libgo/go/big/int_test.go
+++ b/libgo/go/big/int_test.go
@@ -536,7 +536,7 @@ func TestScan(t *testing.T) {
 		buf.Reset()
 		buf.WriteString(test.input)
 		if _, err := fmt.Fscanf(&buf, test.format, x); err != nil {
-			t.Errorf("#%d error: %s", i, err.String())
+			t.Errorf("#%d error: %s", i, err)
 		}
 		if x.String() != test.output {
 			t.Errorf("#%d got %s; want %s", i, x.String(), test.output)
diff --git a/libgo/go/big/nat.go b/libgo/go/big/nat.go
index c0769d8..fa0d7e7 100644
--- a/libgo/go/big/nat.go
+++ b/libgo/go/big/nat.go
@@ -589,15 +589,15 @@ func (x nat) bitLen() int {
 // MaxBase is the largest number base accepted for string conversions.
 const MaxBase = 'z' - 'a' + 10 + 1 // = hexValue('z') + 1
 
-func hexValue(ch int) Word {
+func hexValue(ch rune) Word {
 	d := MaxBase + 1 // illegal base
 	switch {
 	case '0' <= ch && ch <= '9':
-		d = ch - '0'
+		d = int(ch - '0')
 	case 'a' <= ch && ch <= 'z':
-		d = ch - 'a' + 10
+		d = int(ch - 'a' + 10)
 	case 'A' <= ch && ch <= 'Z':
-		d = ch - 'A' + 10
+		d = int(ch - 'A' + 10)
 	}
 	return Word(d)
 }
diff --git a/libgo/go/big/nat_test.go b/libgo/go/big/nat_test.go
index 4f57328..ab34c6e 100644
--- a/libgo/go/big/nat_test.go
+++ b/libgo/go/big/nat_test.go
@@ -231,7 +231,7 @@ var natScanTests = []struct {
 	x    nat    // expected nat
 	b    int    // expected base
 	ok   bool   // expected success
-	next int    // next character (or 0, if at EOF)
+	next rune   // next character (or 0, if at EOF)
 }{
 	// error: illegal base
 	{base: -1},
diff --git a/libgo/go/big/rat.go b/libgo/go/big/rat.go
index 6b86062..1940a05 100644
--- a/libgo/go/big/rat.go
+++ b/libgo/go/big/rat.go
@@ -249,13 +249,13 @@ func (z *Rat) Quo(x, y *Rat) *Rat {
 	return z.norm()
 }
 
-func ratTok(ch int) bool {
+func ratTok(ch rune) bool {
 	return strings.IndexRune("+-/0123456789.eE", ch) >= 0
 }
 
 // Scan is a support routine for fmt.Scanner. It accepts the formats
 // 'e', 'E', 'f', 'F', 'g', 'G', and 'v'. All formats are equivalent.
-func (z *Rat) Scan(s fmt.ScanState, ch int) os.Error {
+func (z *Rat) Scan(s fmt.ScanState, ch rune) os.Error {
 	tok, err := s.Token(true, ratTok)
 	if err != nil {
 		return err
diff --git a/libgo/go/big/rat_test.go b/libgo/go/big/rat_test.go
index a95e5fe..2443450 100644
--- a/libgo/go/big/rat_test.go
+++ b/libgo/go/big/rat_test.go
@@ -112,7 +112,7 @@ func TestRatScan(t *testing.T) {
 		_, err := fmt.Fscanf(&buf, "%v", x)
 		if err == nil != test.ok {
 			if test.ok {
-				t.Errorf("#%d error: %s", i, err.String())
+				t.Errorf("#%d error: %s", i, err)
 			} else {
 				t.Errorf("#%d expected error", i)
 			}
diff --git a/libgo/go/bufio/bufio.go b/libgo/go/bufio/bufio.go
index 2ea7af3..3a4e0ed 100644
--- a/libgo/go/bufio/bufio.go
+++ b/libgo/go/bufio/bufio.go
@@ -208,7 +208,7 @@ func (b *Reader) UnreadByte() os.Error {
 
 // ReadRune reads a single UTF-8 encoded Unicode character and returns the
 // rune and its size in bytes.
-func (b *Reader) ReadRune() (rune int, size int, err os.Error) {
+func (b *Reader) ReadRune() (r rune, size int, err os.Error) {
 	for b.r+utf8.UTFMax > b.w && !utf8.FullRune(b.buf[b.r:b.w]) && b.err == nil {
 		b.fill()
 	}
@@ -216,14 +216,14 @@ func (b *Reader) ReadRune() (rune int, size int, err os.Error) {
 	if b.r == b.w {
 		return 0, 0, b.readErr()
 	}
-	rune, size = int(b.buf[b.r]), 1
-	if rune >= 0x80 {
-		rune, size = utf8.DecodeRune(b.buf[b.r:b.w])
+	r, size = rune(b.buf[b.r]), 1
+	if r >= 0x80 {
+		r, size = utf8.DecodeRune(b.buf[b.r:b.w])
 	}
 	b.r += size
 	b.lastByte = int(b.buf[b.r-1])
 	b.lastRuneSize = size
-	return rune, size, nil
+	return r, size, nil
 }
 
 // UnreadRune unreads the last rune.  If the most recent read operation on
@@ -497,9 +497,9 @@ func (b *Writer) WriteByte(c byte) os.Error {
 
 // WriteRune writes a single Unicode code point, returning
 // the number of bytes written and any error.
-func (b *Writer) WriteRune(rune int) (size int, err os.Error) {
-	if rune < utf8.RuneSelf {
-		err = b.WriteByte(byte(rune))
+func (b *Writer) WriteRune(r rune) (size int, err os.Error) {
+	if r < utf8.RuneSelf {
+		err = b.WriteByte(byte(r))
 		if err != nil {
 			return 0, err
 		}
@@ -516,10 +516,10 @@ func (b *Writer) WriteRune(rune int) (size int, err os.Error) {
 		n = b.Available()
 		if n < utf8.UTFMax {
 			// Can only happen if buffer is silly small.
-			return b.WriteString(string(rune))
+			return b.WriteString(string(r))
 		}
 	}
-	size = utf8.EncodeRune(b.buf[b.n:], rune)
+	size = utf8.EncodeRune(b.buf[b.n:], r)
 	b.n += size
 	return size, nil
 }
diff --git a/libgo/go/bufio/bufio_test.go b/libgo/go/bufio/bufio_test.go
index 38213ff..4fd5f90 100644
--- a/libgo/go/bufio/bufio_test.go
+++ b/libgo/go/bufio/bufio_test.go
@@ -195,14 +195,14 @@ func readRuneSegments(t *testing.T, segments []string) {
 	want := strings.Join(segments, "")
 	r := NewReader(&StringReader{data: segments})
 	for {
-		rune, _, err := r.ReadRune()
+		r, _, err := r.ReadRune()
 		if err != nil {
 			if err != os.EOF {
 				return
 			}
 			break
 		}
-		got += string(rune)
+		got += string(r)
 	}
 	if got != want {
 		t.Errorf("segments=%v got=%s want=%s", segments, got, want)
@@ -233,24 +233,24 @@ func TestUnreadRune(t *testing.T) {
 	r := NewReader(&StringReader{data: segments})
 	// Normal execution.
 	for {
-		rune, _, err := r.ReadRune()
+		r1, _, err := r.ReadRune()
 		if err != nil {
 			if err != os.EOF {
 				t.Error("unexpected EOF")
 			}
 			break
 		}
-		got += string(rune)
+		got += string(r1)
 		// Put it back and read it again
 		if err = r.UnreadRune(); err != nil {
 			t.Error("unexpected error on UnreadRune:", err)
 		}
-		rune1, _, err := r.ReadRune()
+		r2, _, err := r.ReadRune()
 		if err != nil {
 			t.Error("unexpected error reading after unreading:", err)
 		}
-		if rune != rune1 {
-			t.Errorf("incorrect rune after unread: got %c wanted %c", rune1, rune)
+		if r1 != r2 {
+			t.Errorf("incorrect rune after unread: got %c wanted %c", r1, r2)
 		}
 	}
 	if got != data {
@@ -339,25 +339,25 @@ func TestReadWriteRune(t *testing.T) {
 	w := NewWriter(byteBuf)
 	// Write the runes out using WriteRune
 	buf := make([]byte, utf8.UTFMax)
-	for rune := 0; rune < NRune; rune++ {
-		size := utf8.EncodeRune(buf, rune)
-		nbytes, err := w.WriteRune(rune)
+	for r := rune(0); r < NRune; r++ {
+		size := utf8.EncodeRune(buf, r)
+		nbytes, err := w.WriteRune(r)
 		if err != nil {
-			t.Fatalf("WriteRune(0x%x) error: %s", rune, err)
+			t.Fatalf("WriteRune(0x%x) error: %s", r, err)
 		}
 		if nbytes != size {
-			t.Fatalf("WriteRune(0x%x) expected %d, got %d", rune, size, nbytes)
+			t.Fatalf("WriteRune(0x%x) expected %d, got %d", r, size, nbytes)
 		}
 	}
 	w.Flush()
 
 	r := NewReader(byteBuf)
 	// Read them back with ReadRune
-	for rune := 0; rune < NRune; rune++ {
-		size := utf8.EncodeRune(buf, rune)
+	for r1 := rune(0); r1 < NRune; r1++ {
+		size := utf8.EncodeRune(buf, r1)
 		nr, nbytes, err := r.ReadRune()
-		if nr != rune || nbytes != size || err != nil {
-			t.Fatalf("ReadRune(0x%x) got 0x%x,%d not 0x%x,%d (err=%s)", r, nr, nbytes, r, size, err)
+		if nr != r1 || nbytes != size || err != nil {
+			t.Fatalf("ReadRune(0x%x) got 0x%x,%d not 0x%x,%d (err=%s)", r1, nr, nbytes, r1, size, err)
 		}
 	}
 }
diff --git a/libgo/go/bytes/buffer.go b/libgo/go/bytes/buffer.go
index 975031b..c2a8c9f 100644
--- a/libgo/go/bytes/buffer.go
+++ b/libgo/go/bytes/buffer.go
@@ -188,7 +188,7 @@ func (b *Buffer) WriteByte(c byte) os.Error {
 // code point r to the buffer, returning its length and
 // an error, which is always nil but is included
 // to match bufio.Writer's WriteRune.
-func (b *Buffer) WriteRune(r int) (n int, err os.Error) {
+func (b *Buffer) WriteRune(r rune) (n int, err os.Error) {
 	if r < utf8.RuneSelf {
 		b.WriteByte(byte(r))
 		return 1, nil
@@ -255,7 +255,7 @@ func (b *Buffer) ReadByte() (c byte, err os.Error) {
 // If no bytes are available, the error returned is os.EOF.
 // If the bytes are an erroneous UTF-8 encoding, it
 // consumes one byte and returns U+FFFD, 1.
-func (b *Buffer) ReadRune() (r int, size int, err os.Error) {
+func (b *Buffer) ReadRune() (r rune, size int, err os.Error) {
 	b.lastRead = opInvalid
 	if b.off >= len(b.buf) {
 		// Buffer is empty, reset to recover space.
@@ -266,7 +266,7 @@ func (b *Buffer) ReadRune() (r int, size int, err os.Error) {
 	c := b.buf[b.off]
 	if c < utf8.RuneSelf {
 		b.off++
-		return int(c), 1, nil
+		return rune(c), 1, nil
 	}
 	r, n := utf8.DecodeRune(b.buf[b.off:])
 	b.off += n
diff --git a/libgo/go/bytes/buffer_test.go b/libgo/go/bytes/buffer_test.go
index 06d2a65..ee38e08 100644
--- a/libgo/go/bytes/buffer_test.go
+++ b/libgo/go/bytes/buffer_test.go
@@ -264,7 +264,7 @@ func TestRuneIO(t *testing.T) {
 	b := make([]byte, utf8.UTFMax*NRune)
 	var buf Buffer
 	n := 0
-	for r := 0; r < NRune; r++ {
+	for r := rune(0); r < NRune; r++ {
 		size := utf8.EncodeRune(b[n:], r)
 		nbytes, err := buf.WriteRune(r)
 		if err != nil {
@@ -284,7 +284,7 @@ func TestRuneIO(t *testing.T) {
 
 	p := make([]byte, utf8.UTFMax)
 	// Read it back with ReadRune
-	for r := 0; r < NRune; r++ {
+	for r := rune(0); r < NRune; r++ {
 		size := utf8.EncodeRune(p, r)
 		nr, nbytes, err := buf.ReadRune()
 		if nr != r || nbytes != size || err != nil {
@@ -295,7 +295,7 @@ func TestRuneIO(t *testing.T) {
 	// Check that UnreadRune works
 	buf.Reset()
 	buf.Write(b)
-	for r := 0; r < NRune; r++ {
+	for r := rune(0); r < NRune; r++ {
 		r1, size, _ := buf.ReadRune()
 		if err := buf.UnreadRune(); err != nil {
 			t.Fatalf("UnreadRune(%U) got error %q", r, err)
diff --git a/libgo/go/bytes/bytes.go b/libgo/go/bytes/bytes.go
index 2fb4569..ac8320f 100644
--- a/libgo/go/bytes/bytes.go
+++ b/libgo/go/bytes/bytes.go
@@ -130,10 +130,10 @@ func LastIndex(s, sep []byte) int {
 // IndexRune interprets s as a sequence of UTF-8-encoded Unicode code points.
 // It returns the byte index of the first occurrence in s of the given rune.
 // It returns -1 if rune is not present in s.
-func IndexRune(s []byte, rune int) int {
+func IndexRune(s []byte, r rune) int {
 	for i := 0; i < len(s); {
-		r, size := utf8.DecodeRune(s[i:])
-		if r == rune {
+		r1, size := utf8.DecodeRune(s[i:])
+		if r == r1 {
 			return i
 		}
 		i += size
@@ -147,16 +147,17 @@ func IndexRune(s []byte, rune int) int {
 // point in common.
 func IndexAny(s []byte, chars string) int {
 	if len(chars) > 0 {
-		var rune, width int
+		var r rune
+		var width int
 		for i := 0; i < len(s); i += width {
-			rune = int(s[i])
-			if rune < utf8.RuneSelf {
+			r = rune(s[i])
+			if r < utf8.RuneSelf {
 				width = 1
 			} else {
-				rune, width = utf8.DecodeRune(s[i:])
+				r, width = utf8.DecodeRune(s[i:])
 			}
-			for _, r := range chars {
-				if rune == r {
+			for _, ch := range chars {
+				if r == ch {
 					return i
 				}
 			}
@@ -172,10 +173,10 @@ func IndexAny(s []byte, chars string) int {
 func LastIndexAny(s []byte, chars string) int {
 	if len(chars) > 0 {
 		for i := len(s); i > 0; {
-			rune, size := utf8.DecodeLastRune(s[0:i])
+			r, size := utf8.DecodeLastRune(s[0:i])
 			i -= size
-			for _, m := range chars {
-				if rune == m {
+			for _, ch := range chars {
+				if r == ch {
 					return i
 				}
 			}
@@ -256,13 +257,13 @@ func Fields(s []byte) [][]byte {
 // It splits the array s at each run of code points c satisfying f(c) and
 // returns a slice of subarrays of s.  If no code points in s satisfy f(c), an
 // empty slice is returned.
-func FieldsFunc(s []byte, f func(int) bool) [][]byte {
+func FieldsFunc(s []byte, f func(rune) bool) [][]byte {
 	n := 0
 	inField := false
 	for i := 0; i < len(s); {
-		rune, size := utf8.DecodeRune(s[i:])
+		r, size := utf8.DecodeRune(s[i:])
 		wasInField := inField
-		inField = !f(rune)
+		inField = !f(r)
 		if inField && !wasInField {
 			n++
 		}
@@ -273,13 +274,13 @@ func FieldsFunc(s []byte, f func(int) bool) [][]byte {
 	na := 0
 	fieldStart := -1
 	for i := 0; i <= len(s) && na < n; {
-		rune, size := utf8.DecodeRune(s[i:])
-		if fieldStart < 0 && size > 0 && !f(rune) {
+		r, size := utf8.DecodeRune(s[i:])
+		if fieldStart < 0 && size > 0 && !f(r) {
 			fieldStart = i
 			i += size
 			continue
 		}
-		if fieldStart >= 0 && (size == 0 || f(rune)) {
+		if fieldStart >= 0 && (size == 0 || f(r)) {
 			a[na] = s[fieldStart:i]
 			na++
 			fieldStart = -1
@@ -329,7 +330,7 @@ func HasSuffix(s, suffix []byte) bool {
 // according to the mapping function. If mapping returns a negative value, the character is
 // dropped from the string with no replacement.  The characters in s and the
 // output are interpreted as UTF-8-encoded Unicode code points.
-func Map(mapping func(rune int) int, s []byte) []byte {
+func Map(mapping func(r rune) rune, s []byte) []byte {
 	// In the worst case, the array can grow when mapped, making
 	// things unpleasant.  But it's so rare we barge in assuming it's
 	// fine.  It could also shrink but that falls out naturally.
@@ -338,20 +339,20 @@ func Map(mapping func(rune int) int, s []byte) []byte {
 	b := make([]byte, maxbytes)
 	for i := 0; i < len(s); {
 		wid := 1
-		rune := int(s[i])
-		if rune >= utf8.RuneSelf {
-			rune, wid = utf8.DecodeRune(s[i:])
+		r := rune(s[i])
+		if r >= utf8.RuneSelf {
+			r, wid = utf8.DecodeRune(s[i:])
 		}
-		rune = mapping(rune)
-		if rune >= 0 {
-			if nbytes+utf8.RuneLen(rune) > maxbytes {
+		r = mapping(r)
+		if r >= 0 {
+			if nbytes+utf8.RuneLen(r) > maxbytes {
 				// Grow the buffer.
 				maxbytes = maxbytes*2 + utf8.UTFMax
 				nb := make([]byte, maxbytes)
 				copy(nb, b[0:nbytes])
 				b = nb
 			}
-			nbytes += utf8.EncodeRune(b[nbytes:maxbytes], rune)
+			nbytes += utf8.EncodeRune(b[nbytes:maxbytes], r)
 		}
 		i += wid
 	}
@@ -383,44 +384,44 @@ func ToTitle(s []byte) []byte { return Map(unicode.ToTitle, s) }
 // ToUpperSpecial returns a copy of the byte array s with all Unicode letters mapped to their
 // upper case, giving priority to the special casing rules.
 func ToUpperSpecial(_case unicode.SpecialCase, s []byte) []byte {
-	return Map(func(r int) int { return _case.ToUpper(r) }, s)
+	return Map(func(r rune) rune { return _case.ToUpper(r) }, s)
 }
 
 // ToLowerSpecial returns a copy of the byte array s with all Unicode letters mapped to their
 // lower case, giving priority to the special casing rules.
 func ToLowerSpecial(_case unicode.SpecialCase, s []byte) []byte {
-	return Map(func(r int) int { return _case.ToLower(r) }, s)
+	return Map(func(r rune) rune { return _case.ToLower(r) }, s)
 }
 
 // ToTitleSpecial returns a copy of the byte array s with all Unicode letters mapped to their
 // title case, giving priority to the special casing rules.
 func ToTitleSpecial(_case unicode.SpecialCase, s []byte) []byte {
-	return Map(func(r int) int { return _case.ToTitle(r) }, s)
+	return Map(func(r rune) rune { return _case.ToTitle(r) }, s)
 }
 
 // isSeparator reports whether the rune could mark a word boundary.
 // TODO: update when package unicode captures more of the properties.
-func isSeparator(rune int) bool {
+func isSeparator(r rune) bool {
 	// ASCII alphanumerics and underscore are not separators
-	if rune <= 0x7F {
+	if r <= 0x7F {
 		switch {
-		case '0' <= rune && rune <= '9':
+		case '0' <= r && r <= '9':
 			return false
-		case 'a' <= rune && rune <= 'z':
+		case 'a' <= r && r <= 'z':
 			return false
-		case 'A' <= rune && rune <= 'Z':
+		case 'A' <= r && r <= 'Z':
 			return false
-		case rune == '_':
+		case r == '_':
 			return false
 		}
 		return true
 	}
 	// Letters and digits are not separators
-	if unicode.IsLetter(rune) || unicode.IsDigit(rune) {
+	if unicode.IsLetter(r) || unicode.IsDigit(r) {
 		return false
 	}
 	// Otherwise, all we can do for now is treat spaces as separators.
-	return unicode.IsSpace(rune)
+	return unicode.IsSpace(r)
 }
 
 // BUG(r): The rule Title uses for word boundaries does not handle Unicode punctuation properly.
@@ -431,9 +432,9 @@ func Title(s []byte) []byte {
 	// Use a closure here to remember state.
 	// Hackish but effective. Depends on Map scanning in order and calling
 	// the closure once per rune.
-	prev := ' '
+	prev := rune(' ')
 	return Map(
-		func(r int) int {
+		func(r rune) rune {
 			if isSeparator(prev) {
 				prev = r
 				return unicode.ToTitle(r)
@@ -446,7 +447,7 @@ func Title(s []byte) []byte {
 
 // TrimLeftFunc returns a subslice of s by slicing off all leading UTF-8-encoded
 // Unicode code points c that satisfy f(c).
-func TrimLeftFunc(s []byte, f func(r int) bool) []byte {
+func TrimLeftFunc(s []byte, f func(r rune) bool) []byte {
 	i := indexFunc(s, f, false)
 	if i == -1 {
 		return nil
@@ -456,7 +457,7 @@ func TrimLeftFunc(s []byte, f func(r int) bool) []byte {
 
 // TrimRightFunc returns a subslice of s by slicing off all trailing UTF-8
 // encoded Unicode code points c that satisfy f(c).
-func TrimRightFunc(s []byte, f func(r int) bool) []byte {
+func TrimRightFunc(s []byte, f func(r rune) bool) []byte {
 	i := lastIndexFunc(s, f, false)
 	if i >= 0 && s[i] >= utf8.RuneSelf {
 		_, wid := utf8.DecodeRune(s[i:])
@@ -469,36 +470,36 @@ func TrimRightFunc(s []byte, f func(r int) bool) []byte {
 
 // TrimFunc returns a subslice of s by slicing off all leading and trailing
 // UTF-8-encoded Unicode code points c that satisfy f(c).
-func TrimFunc(s []byte, f func(r int) bool) []byte {
+func TrimFunc(s []byte, f func(r rune) bool) []byte {
 	return TrimRightFunc(TrimLeftFunc(s, f), f)
 }
 
 // IndexFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
 // It returns the byte index in s of the first Unicode
 // code point satisfying f(c), or -1 if none do.
-func IndexFunc(s []byte, f func(r int) bool) int {
+func IndexFunc(s []byte, f func(r rune) bool) int {
 	return indexFunc(s, f, true)
 }
 
 // LastIndexFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
 // It returns the byte index in s of the last Unicode
 // code point satisfying f(c), or -1 if none do.
-func LastIndexFunc(s []byte, f func(r int) bool) int {
+func LastIndexFunc(s []byte, f func(r rune) bool) int {
 	return lastIndexFunc(s, f, true)
 }
 
 // indexFunc is the same as IndexFunc except that if
 // truth==false, the sense of the predicate function is
 // inverted.
-func indexFunc(s []byte, f func(r int) bool, truth bool) int {
+func indexFunc(s []byte, f func(r rune) bool, truth bool) int {
 	start := 0
 	for start < len(s) {
 		wid := 1
-		rune := int(s[start])
-		if rune >= utf8.RuneSelf {
-			rune, wid = utf8.DecodeRune(s[start:])
+		r := rune(s[start])
+		if r >= utf8.RuneSelf {
+			r, wid = utf8.DecodeRune(s[start:])
 		}
-		if f(rune) == truth {
+		if f(r) == truth {
 			return start
 		}
 		start += wid
@@ -509,21 +510,21 @@ func indexFunc(s []byte, f func(r int) bool, truth bool) int {
 // lastIndexFunc is the same as LastIndexFunc except that if
 // truth==false, the sense of the predicate function is
 // inverted.
-func lastIndexFunc(s []byte, f func(r int) bool, truth bool) int {
+func lastIndexFunc(s []byte, f func(r rune) bool, truth bool) int {
 	for i := len(s); i > 0; {
-		rune, size := utf8.DecodeLastRune(s[0:i])
+		r, size := utf8.DecodeLastRune(s[0:i])
 		i -= size
-		if f(rune) == truth {
+		if f(r) == truth {
 			return i
 		}
 	}
 	return -1
 }
 
-func makeCutsetFunc(cutset string) func(rune int) bool {
-	return func(rune int) bool {
+func makeCutsetFunc(cutset string) func(r rune) bool {
+	return func(r rune) bool {
 		for _, c := range cutset {
-			if c == rune {
+			if c == r {
 				return true
 			}
 		}
@@ -556,8 +557,8 @@ func TrimSpace(s []byte) []byte {
 }
 
 // Runes returns a slice of runes (Unicode code points) equivalent to s.
-func Runes(s []byte) []int {
-	t := make([]int, utf8.RuneCount(s))
+func Runes(s []byte) []rune {
+	t := make([]rune, utf8.RuneCount(s))
 	i := 0
 	for len(s) > 0 {
 		r, l := utf8.DecodeRune(s)
@@ -614,15 +615,15 @@ func Replace(s, old, new []byte, n int) []byte {
 func EqualFold(s, t []byte) bool {
 	for len(s) != 0 && len(t) != 0 {
 		// Extract first rune from each.
-		var sr, tr int
+		var sr, tr rune
 		if s[0] < utf8.RuneSelf {
-			sr, s = int(s[0]), s[1:]
+			sr, s = rune(s[0]), s[1:]
 		} else {
 			r, size := utf8.DecodeRune(s)
 			sr, s = r, s[size:]
 		}
 		if t[0] < utf8.RuneSelf {
-			tr, t = int(t[0]), t[1:]
+			tr, t = rune(t[0]), t[1:]
 		} else {
 			r, size := utf8.DecodeRune(t)
 			tr, t = r, t[size:]
diff --git a/libgo/go/bytes/bytes_test.go b/libgo/go/bytes/bytes_test.go
index ce3f37e..62f258d 100644
--- a/libgo/go/bytes/bytes_test.go
+++ b/libgo/go/bytes/bytes_test.go
@@ -444,7 +444,7 @@ func TestFields(t *testing.T) {
 }
 
 func TestFieldsFunc(t *testing.T) {
-	pred := func(c int) bool { return c == 'X' }
+	pred := func(c rune) bool { return c == 'X' }
 	var fieldsFuncTests = []FieldsTest{
 		{"", []string{}},
 		{"XX", []string{}},
@@ -514,24 +514,24 @@ func runStringTests(t *testing.T, f func([]byte) []byte, funcName string, testCa
 	}
 }
 
-func tenRunes(rune int) string {
-	r := make([]int, 10)
-	for i := range r {
-		r[i] = rune
+func tenRunes(r rune) string {
+	runes := make([]rune, 10)
+	for i := range runes {
+		runes[i] = r
 	}
-	return string(r)
+	return string(runes)
 }
 
 // User-defined self-inverse mapping function
-func rot13(rune int) int {
-	step := 13
-	if rune >= 'a' && rune <= 'z' {
-		return ((rune - 'a' + step) % 26) + 'a'
+func rot13(r rune) rune {
+	const step = 13
+	if r >= 'a' && r <= 'z' {
+		return ((r - 'a' + step) % 26) + 'a'
 	}
-	if rune >= 'A' && rune <= 'Z' {
-		return ((rune - 'A' + step) % 26) + 'A'
+	if r >= 'A' && r <= 'Z' {
+		return ((r - 'A' + step) % 26) + 'A'
 	}
-	return rune
+	return r
 }
 
 func TestMap(t *testing.T) {
@@ -539,7 +539,7 @@ func TestMap(t *testing.T) {
 	a := tenRunes('a')
 
 	// 1.  Grow.  This triggers two reallocations in Map.
-	maxRune := func(rune int) int { return unicode.MaxRune }
+	maxRune := func(r rune) rune { return unicode.MaxRune }
 	m := Map(maxRune, []byte(a))
 	expect := tenRunes(unicode.MaxRune)
 	if string(m) != expect {
@@ -547,7 +547,7 @@ func TestMap(t *testing.T) {
 	}
 
 	// 2. Shrink
-	minRune := func(rune int) int { return 'a' }
+	minRune := func(r rune) rune { return 'a' }
 	m = Map(minRune, []byte(tenRunes(unicode.MaxRune)))
 	expect = a
 	if string(m) != expect {
@@ -569,9 +569,9 @@ func TestMap(t *testing.T) {
 	}
 
 	// 5. Drop
-	dropNotLatin := func(rune int) int {
-		if unicode.Is(unicode.Latin, rune) {
-			return rune
+	dropNotLatin := func(r rune) rune {
+		if unicode.Is(unicode.Latin, r) {
+			return r
 		}
 		return -1
 	}
@@ -615,7 +615,7 @@ func TestRepeat(t *testing.T) {
 	}
 }
 
-func runesEqual(a, b []int) bool {
+func runesEqual(a, b []rune) bool {
 	if len(a) != len(b) {
 		return false
 	}
@@ -629,18 +629,18 @@ func runesEqual(a, b []int) bool {
 
 type RunesTest struct {
 	in    string
-	out   []int
+	out   []rune
 	lossy bool
 }
 
 var RunesTests = []RunesTest{
-	{"", []int{}, false},
-	{" ", []int{32}, false},
-	{"ABC", []int{65, 66, 67}, false},
-	{"abc", []int{97, 98, 99}, false},
-	{"\u65e5\u672c\u8a9e", []int{26085, 26412, 35486}, false},
-	{"ab\x80c", []int{97, 98, 0xFFFD, 99}, true},
-	{"ab\xc0c", []int{97, 98, 0xFFFD, 99}, true},
+	{"", []rune{}, false},
+	{" ", []rune{32}, false},
+	{"ABC", []rune{65, 66, 67}, false},
+	{"abc", []rune{97, 98, 99}, false},
+	{"\u65e5\u672c\u8a9e", []rune{26085, 26412, 35486}, false},
+	{"ab\x80c", []rune{97, 98, 0xFFFD, 99}, true},
+	{"ab\xc0c", []rune{97, 98, 0xFFFD, 99}, true},
 }
 
 func TestRunes(t *testing.T) {
@@ -711,7 +711,7 @@ func TestTrim(t *testing.T) {
 }
 
 type predicate struct {
-	f    func(r int) bool
+	f    func(r rune) bool
 	name string
 }
 
@@ -719,7 +719,7 @@ var isSpace = predicate{unicode.IsSpace, "IsSpace"}
 var isDigit = predicate{unicode.IsDigit, "IsDigit"}
 var isUpper = predicate{unicode.IsUpper, "IsUpper"}
 var isValidRune = predicate{
-	func(r int) bool {
+	func(r rune) bool {
 		return r != utf8.RuneError
 	},
 	"IsValidRune",
@@ -732,7 +732,7 @@ type TrimFuncTest struct {
 
 func not(p predicate) predicate {
 	return predicate{
-		func(r int) bool {
+		func(r rune) bool {
 			return !p.f(r)
 		},
 		"not " + p.name,
diff --git a/libgo/go/crypto/bcrypt/bcrypt_test.go b/libgo/go/crypto/bcrypt/bcrypt_test.go
index 89eca0a..3efbc1c 100644
--- a/libgo/go/crypto/bcrypt/bcrypt_test.go
+++ b/libgo/go/crypto/bcrypt/bcrypt_test.go
@@ -86,7 +86,7 @@ func TestInvalidHashErrors(t *testing.T) {
 			t.Errorf("%s: Should have returned an error", name)
 		}
 		if err != nil && err != expected {
-			t.Errorf("%s gave err %v but should have given %v", name, err.String(), expected.String())
+			t.Errorf("%s gave err %v but should have given %v", name, err, expected)
 		}
 	}
 	for _, iht := range invalidTests {
diff --git a/libgo/go/crypto/openpgp/error/error.go b/libgo/go/crypto/openpgp/error/error.go
index 3759ce1..9cc21f1 100644
--- a/libgo/go/crypto/openpgp/error/error.go
+++ b/libgo/go/crypto/openpgp/error/error.go
@@ -41,21 +41,21 @@ func (b SignatureError) String() string {
 	return "OpenPGP signature invalid: " + string(b)
 }
 
-type keyIncorrect int
+type keyIncorrectError int
 
-func (ki keyIncorrect) String() string {
+func (ki keyIncorrectError) String() string {
 	return "the given key was incorrect"
 }
 
-var KeyIncorrectError = keyIncorrect(0)
+var KeyIncorrectError = keyIncorrectError(0)
 
-type unknownIssuer int
+type unknownIssuerError int
 
-func (unknownIssuer) String() string {
+func (unknownIssuerError) String() string {
 	return "signature make by unknown entity"
 }
 
-var UnknownIssuerError = unknownIssuer(0)
+var UnknownIssuerError = unknownIssuerError(0)
 
 type UnknownPacketTypeError uint8
 
diff --git a/libgo/go/crypto/rsa/rsa.go b/libgo/go/crypto/rsa/rsa.go
index 6957659..3df88e0 100644
--- a/libgo/go/crypto/rsa/rsa.go
+++ b/libgo/go/crypto/rsa/rsa.go
@@ -116,15 +116,7 @@ func GenerateKey(random io.Reader, bits int) (priv *PrivateKey, err os.Error) {
 // [2] http://www.cacr.math.uwaterloo.ca/techreports/2006/cacr2006-16.pdf
 func GenerateMultiPrimeKey(random io.Reader, nprimes int, bits int) (priv *PrivateKey, err os.Error) {
 	priv = new(PrivateKey)
-	// Smaller public exponents lead to faster public key
-	// operations. Since the exponent must be coprime to
-	// (p-1)(q-1), the smallest possible value is 3. Some have
-	// suggested that a larger exponent (often 2**16+1) be used
-	// since previous implementation bugs[1] were avoided when this
-	// was the case. However, there are no current reasons not to use
-	// small exponents.
-	// [1] http://marc.info/?l=cryptography&m=115694833312008&w=2
-	priv.E = 3
+	priv.E = 65537
 
 	if nprimes < 2 {
 		return nil, os.NewError("rsa.GenerateMultiPrimeKey: nprimes must be >= 2")
diff --git a/libgo/go/crypto/tls/alert.go b/libgo/go/crypto/tls/alert.go
index 3b9e0e2..0856311 100644
--- a/libgo/go/crypto/tls/alert.go
+++ b/libgo/go/crypto/tls/alert.go
@@ -71,3 +71,7 @@ func (e alert) String() string {
 	}
 	return "alert(" + strconv.Itoa(int(e)) + ")"
 }
+
+func (e alert) Error() string {
+	return e.String()
+}
diff --git a/libgo/go/csv/reader.go b/libgo/go/csv/reader.go
index 29ceeae..a06b978 100644
--- a/libgo/go/csv/reader.go
+++ b/libgo/go/csv/reader.go
@@ -101,8 +101,8 @@ var (
 //
 // If TrimLeadingSpace is true, leading white space in a field is ignored.
 type Reader struct {
-	Comma            int  // Field delimiter (set to ',' by NewReader)
-	Comment          int  // Comment character for start of line
+	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
@@ -173,23 +173,23 @@ func (r *Reader) ReadAll() (records [][]string, err os.Error) {
 // readRune reads one rune from r, folding \r\n to \n and keeping track
 // of how far into the line we have read.  r.column will point to the start
 // of this rune, not the end of this rune.
-func (r *Reader) readRune() (int, os.Error) {
-	rune, _, err := r.r.ReadRune()
+func (r *Reader) readRune() (rune, os.Error) {
+	r1, _, err := r.r.ReadRune()
 
 	// Handle \r\n here.  We make the simplifying assumption that
 	// anytime \r is followed by \n that it can be folded to \n.
 	// We will not detect files which contain both \r\n and bare \n.
-	if rune == '\r' {
-		rune, _, err = r.r.ReadRune()
+	if r1 == '\r' {
+		r1, _, err = r.r.ReadRune()
 		if err == nil {
-			if rune != '\n' {
+			if r1 != '\n' {
 				r.r.UnreadRune()
-				rune = '\r'
+				r1 = '\r'
 			}
 		}
 	}
 	r.column++
-	return rune, err
+	return r1, err
 }
 
 // unreadRune puts the last rune read from r back.
@@ -199,13 +199,13 @@ func (r *Reader) unreadRune() {
 }
 
 // skip reads runes up to and including the rune delim or until error.
-func (r *Reader) skip(delim int) os.Error {
+func (r *Reader) skip(delim rune) os.Error {
 	for {
-		rune, err := r.readRune()
+		r1, err := r.readRune()
 		if err != nil {
 			return err
 		}
-		if rune == delim {
+		if r1 == delim {
 			return nil
 		}
 	}
@@ -224,12 +224,12 @@ func (r *Reader) parseRecord() (fields []string, err os.Error) {
 	// If we are support comments and it is the comment character
 	// then skip to the end of line.
 
-	rune, _, err := r.r.ReadRune()
+	r1, _, err := r.r.ReadRune()
 	if err != nil {
 		return nil, err
 	}
 
-	if r.Comment != 0 && rune == r.Comment {
+	if r.Comment != 0 && r1 == r.Comment {
 		return nil, r.skip('\n')
 	}
 	r.r.UnreadRune()
@@ -252,10 +252,10 @@ func (r *Reader) parseRecord() (fields []string, err os.Error) {
 // parseField parses the next field in the record.  The read field is
 // located in r.field.  Delim is the first character not part of the field
 // (r.Comma or '\n').
-func (r *Reader) parseField() (haveField bool, delim int, err os.Error) {
+func (r *Reader) parseField() (haveField bool, delim rune, err os.Error) {
 	r.field.Reset()
 
-	rune, err := r.readRune()
+	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
@@ -267,30 +267,30 @@ func (r *Reader) parseField() (haveField bool, delim int, err os.Error) {
 	}
 
 	if r.TrimLeadingSpace {
-		for rune != '\n' && unicode.IsSpace(rune) {
-			rune, err = r.readRune()
+		for r1 != '\n' && unicode.IsSpace(r1) {
+			r1, err = r.readRune()
 			if err != nil {
 				return false, 0, err
 			}
 		}
 	}
 
-	switch rune {
+	switch r1 {
 	case r.Comma:
 		// will check below
 
 	case '\n':
 		// We are a trailing empty field or a blank line
 		if r.column == 0 {
-			return false, rune, nil
+			return false, r1, nil
 		}
-		return true, rune, nil
+		return true, r1, nil
 
 	case '"':
 		// quoted field
 	Quoted:
 		for {
-			rune, err = r.readRune()
+			r1, err = r.readRune()
 			if err != nil {
 				if err == os.EOF {
 					if r.LazyQuotes {
@@ -300,16 +300,16 @@ func (r *Reader) parseField() (haveField bool, delim int, err os.Error) {
 				}
 				return false, 0, err
 			}
-			switch rune {
+			switch r1 {
 			case '"':
-				rune, err = r.readRune()
-				if err != nil || rune == r.Comma {
+				r1, err = r.readRune()
+				if err != nil || r1 == r.Comma {
 					break Quoted
 				}
-				if rune == '\n' {
-					return true, rune, nil
+				if r1 == '\n' {
+					return true, r1, nil
 				}
-				if rune != '"' {
+				if r1 != '"' {
 					if !r.LazyQuotes {
 						r.column--
 						return false, 0, r.error(ErrQuote)
@@ -321,21 +321,21 @@ func (r *Reader) parseField() (haveField bool, delim int, err os.Error) {
 				r.line++
 				r.column = -1
 			}
-			r.field.WriteRune(rune)
+			r.field.WriteRune(r1)
 		}
 
 	default:
 		// unquoted field
 		for {
-			r.field.WriteRune(rune)
-			rune, err = r.readRune()
-			if err != nil || rune == r.Comma {
+			r.field.WriteRune(r1)
+			r1, err = r.readRune()
+			if err != nil || r1 == r.Comma {
 				break
 			}
-			if rune == '\n' {
-				return true, rune, nil
+			if r1 == '\n' {
+				return true, r1, nil
 			}
-			if !r.LazyQuotes && rune == '"' {
+			if !r.LazyQuotes && r1 == '"' {
 				return false, 0, r.error(ErrBareQuote)
 			}
 		}
@@ -353,20 +353,20 @@ func (r *Reader) parseField() (haveField bool, delim int, err os.Error) {
 		// are at the end of the line (being mindful
 		// of trimming spaces).
 		c := r.column
-		rune, err = r.readRune()
+		r1, err = r.readRune()
 		if r.TrimLeadingSpace {
-			for rune != '\n' && unicode.IsSpace(rune) {
-				rune, err = r.readRune()
+			for r1 != '\n' && unicode.IsSpace(r1) {
+				r1, err = r.readRune()
 				if err != nil {
 					break
 				}
 			}
 		}
-		if err == os.EOF || rune == '\n' {
+		if err == os.EOF || r1 == '\n' {
 			r.column = c // report the comma
 			return false, 0, r.error(ErrTrailingComma)
 		}
 		r.unreadRune()
 	}
-	return true, rune, nil
+	return true, r1, nil
 }
diff --git a/libgo/go/csv/reader_test.go b/libgo/go/csv/reader_test.go
index 967f96b..1b23605 100644
--- a/libgo/go/csv/reader_test.go
+++ b/libgo/go/csv/reader_test.go
@@ -17,8 +17,8 @@ var readTests = []struct {
 	UseFieldsPerRecord bool // false (default) means FieldsPerRecord is -1
 
 	// These fields are copied into the Reader
-	Comma            int
-	Comment          int
+	Comma            rune
+	Comment          rune
 	FieldsPerRecord  int
 	LazyQuotes       bool
 	TrailingComma    bool
diff --git a/libgo/go/csv/writer.go b/libgo/go/csv/writer.go
index ccf703f..98573c2 100644
--- a/libgo/go/csv/writer.go
+++ b/libgo/go/csv/writer.go
@@ -23,7 +23,7 @@ import (
 //
 // If UseCRLF is true, the Writer ends each record with \r\n instead of \n.
 type Writer struct {
-	Comma   int  // Field delimiter (set to to ',' by NewWriter)
+	Comma   rune // Field delimiter (set to to ',' by NewWriter)
 	UseCRLF bool // True to use \r\n as the line terminator
 	w       *bufio.Writer
 }
@@ -58,8 +58,8 @@ func (w *Writer) Write(record []string) (err os.Error) {
 			return
 		}
 
-		for _, rune := range field {
-			switch rune {
+		for _, r1 := range field {
+			switch r1 {
 			case '"':
 				_, err = w.w.WriteString(`""`)
 			case '\r':
@@ -73,7 +73,7 @@ func (w *Writer) Write(record []string) (err os.Error) {
 					err = w.w.WriteByte('\n')
 				}
 			default:
-				_, err = w.w.WriteRune(rune)
+				_, err = w.w.WriteRune(r1)
 			}
 			if err != nil {
 				return
@@ -117,6 +117,6 @@ func (w *Writer) fieldNeedsQuotes(field string) bool {
 		return true
 	}
 
-	rune, _ := utf8.DecodeRuneInString(field)
-	return unicode.IsSpace(rune)
+	r1, _ := utf8.DecodeRuneInString(field)
+	return unicode.IsSpace(r1)
 }
diff --git a/libgo/go/encoding/binary/binary_test.go b/libgo/go/encoding/binary/binary_test.go
index b266996..ef20605 100644
--- a/libgo/go/encoding/binary/binary_test.go
+++ b/libgo/go/encoding/binary/binary_test.go
@@ -5,10 +5,10 @@
 package binary
 
 import (
-	"io"
-	"os"
 	"bytes"
+	"io"
 	"math"
+	"os"
 	"reflect"
 	"testing"
 )
@@ -99,7 +99,7 @@ var little = []byte{
 var src = []byte{1, 2, 3, 4, 5, 6, 7, 8}
 var res = []int32{0x01020304, 0x05060708}
 
-func checkResult(t *testing.T, dir string, order, err os.Error, have, want interface{}) {
+func checkResult(t *testing.T, dir string, order ByteOrder, err os.Error, have, want interface{}) {
 	if err != nil {
 		t.Errorf("%v %v: %v", dir, order, err)
 		return
diff --git a/libgo/go/exp/ebnf/ebnf.go b/libgo/go/exp/ebnf/ebnf.go
index 2ec7f00..7070cc7 100644
--- a/libgo/go/exp/ebnf/ebnf.go
+++ b/libgo/go/exp/ebnf/ebnf.go
@@ -163,7 +163,7 @@ func (v *verifier) push(prod *Production) {
 	}
 }
 
-func (v *verifier) verifyChar(x *Token) int {
+func (v *verifier) verifyChar(x *Token) rune {
 	s := x.String
 	if utf8.RuneCountInString(s) != 1 {
 		v.error(x.Pos(), "single char expected, found "+s)
diff --git a/libgo/go/exp/ebnf/parser.go b/libgo/go/exp/ebnf/parser.go
index 2dbbefb..dac5dd8 100644
--- a/libgo/go/exp/ebnf/parser.go
+++ b/libgo/go/exp/ebnf/parser.go
@@ -15,7 +15,7 @@ type parser struct {
 	errors  errorList
 	scanner scanner.Scanner
 	pos     scanner.Position // token position
-	tok     int              // one token look-ahead
+	tok     rune             // one token look-ahead
 	lit     string           // token literal
 }
 
@@ -42,7 +42,7 @@ func (p *parser) errorExpected(pos scanner.Position, msg string) {
 	p.error(pos, msg)
 }
 
-func (p *parser) expect(tok int) scanner.Position {
+func (p *parser) expect(tok rune) scanner.Position {
 	pos := p.pos
 	if p.tok != tok {
 		p.errorExpected(pos, scanner.TokenString(tok))
diff --git a/libgo/go/exp/gui/x11/conn.go b/libgo/go/exp/gui/x11/conn.go
index bf94bca..f4a453e 100644
--- a/libgo/go/exp/gui/x11/conn.go
+++ b/libgo/go/exp/gui/x11/conn.go
@@ -87,7 +87,7 @@ func (c *conn) writeSocket() {
 			setU32LE(c.flushBuf0[16:20], uint32(y<<16))
 			if _, err := c.w.Write(c.flushBuf0[:24]); err != nil {
 				if err != os.EOF {
-					log.Println("x11:", err.String())
+					log.Println("x11:", err)
 				}
 				return
 			}
@@ -106,7 +106,7 @@ func (c *conn) writeSocket() {
 				x += nx
 				if _, err := c.w.Write(c.flushBuf1[:nx]); err != nil {
 					if err != os.EOF {
-						log.Println("x11:", err.String())
+						log.Println("x11:", err)
 					}
 					return
 				}
@@ -114,7 +114,7 @@ func (c *conn) writeSocket() {
 		}
 		if err := c.w.Flush(); err != nil {
 			if err != os.EOF {
-				log.Println("x11:", err.String())
+				log.Println("x11:", err)
 			}
 			return
 		}
diff --git a/libgo/go/exp/norm/composition.go b/libgo/go/exp/norm/composition.go
index 1d72223..7965ffc 100644
--- a/libgo/go/exp/norm/composition.go
+++ b/libgo/go/exp/norm/composition.go
@@ -126,26 +126,26 @@ func (rb *reorderBuffer) insert(src input, i int, info runeInfo) bool {
 }
 
 // appendRune inserts a rune at the end of the buffer. It is used for Hangul.
-func (rb *reorderBuffer) appendRune(rune uint32) {
+func (rb *reorderBuffer) appendRune(r uint32) {
 	bn := rb.nbyte
-	sz := utf8.EncodeRune(rb.byte[bn:], int(rune))
+	sz := utf8.EncodeRune(rb.byte[bn:], rune(r))
 	rb.nbyte += utf8.UTFMax
 	rb.rune[rb.nrune] = runeInfo{bn, uint8(sz), 0, 0}
 	rb.nrune++
 }
 
 // assignRune sets a rune at position pos. It is used for Hangul and recomposition.
-func (rb *reorderBuffer) assignRune(pos int, rune uint32) {
+func (rb *reorderBuffer) assignRune(pos int, r uint32) {
 	bn := rb.rune[pos].pos
-	sz := utf8.EncodeRune(rb.byte[bn:], int(rune))
+	sz := utf8.EncodeRune(rb.byte[bn:], rune(r))
 	rb.rune[pos] = runeInfo{bn, uint8(sz), 0, 0}
 }
 
 // runeAt returns the rune at position n. It is used for Hangul and recomposition.
 func (rb *reorderBuffer) runeAt(n int) uint32 {
 	inf := rb.rune[n]
-	rune, _ := utf8.DecodeRune(rb.byte[inf.pos : inf.pos+inf.size])
-	return uint32(rune)
+	r, _ := utf8.DecodeRune(rb.byte[inf.pos : inf.pos+inf.size])
+	return uint32(r)
 }
 
 // bytesAt returns the UTF-8 encoding of the rune at position n.
@@ -237,17 +237,17 @@ func isHangulWithoutJamoT(b []byte) bool {
 // decomposeHangul algorithmically decomposes a Hangul rune into
 // its Jamo components.
 // See http://unicode.org/reports/tr15/#Hangul for details on decomposing Hangul.
-func (rb *reorderBuffer) decomposeHangul(rune uint32) bool {
+func (rb *reorderBuffer) decomposeHangul(r uint32) bool {
 	b := rb.rune[:]
 	n := rb.nrune
 	if n+3 > len(b) {
 		return false
 	}
-	rune -= hangulBase
-	x := rune % jamoTCount
-	rune /= jamoTCount
-	rb.appendRune(jamoLBase + rune/jamoVCount)
-	rb.appendRune(jamoVBase + rune%jamoVCount)
+	r -= hangulBase
+	x := r % jamoTCount
+	r /= jamoTCount
+	rb.appendRune(jamoLBase + r/jamoVCount)
+	rb.appendRune(jamoVBase + r%jamoVCount)
 	if x != 0 {
 		rb.appendRune(jamoTBase + x)
 	}
diff --git a/libgo/go/exp/norm/composition_test.go b/libgo/go/exp/norm/composition_test.go
index ce9caaf..e32380d 100644
--- a/libgo/go/exp/norm/composition_test.go
+++ b/libgo/go/exp/norm/composition_test.go
@@ -8,14 +8,14 @@ import "testing"
 
 // TestCase is used for most tests.
 type TestCase struct {
-	in  []int
-	out []int
+	in  []rune
+	out []rune
 }
 
-type insertFunc func(rb *reorderBuffer, rune int) bool
+type insertFunc func(rb *reorderBuffer, r rune) bool
 
-func insert(rb *reorderBuffer, rune int) bool {
-	src := inputString(string(rune))
+func insert(rb *reorderBuffer, r rune) bool {
+	src := inputString(string(r))
 	return rb.insert(src, 0, rb.f.info(src, 0))
 }
 
@@ -39,7 +39,7 @@ func runTests(t *testing.T, name string, fm Form, f insertFunc, tests []TestCase
 			continue
 		}
 		for j, want := range test.out {
-			found := int(rb.runeAt(j))
+			found := rune(rb.runeAt(j))
 			if found != want {
 				t.Errorf("%s:%d: runeAt(%d) = %U; want %U", name, i, j, found, want)
 			}
@@ -57,7 +57,7 @@ func TestFlush(t *testing.T) {
 		t.Errorf("wrote bytes on flush of empty buffer. (len(out) = %d)", len(out))
 	}
 
-	for _, r := range []int("world!") {
+	for _, r := range []rune("world!") {
 		insert(&rb, r)
 	}
 
@@ -76,14 +76,14 @@ func TestFlush(t *testing.T) {
 }
 
 var insertTests = []TestCase{
-	{[]int{'a'}, []int{'a'}},
-	{[]int{0x300}, []int{0x300}},
-	{[]int{0x300, 0x316}, []int{0x316, 0x300}}, // CCC(0x300)==230; CCC(0x316)==220
-	{[]int{0x316, 0x300}, []int{0x316, 0x300}},
-	{[]int{0x41, 0x316, 0x300}, []int{0x41, 0x316, 0x300}},
-	{[]int{0x41, 0x300, 0x316}, []int{0x41, 0x316, 0x300}},
-	{[]int{0x300, 0x316, 0x41}, []int{0x316, 0x300, 0x41}},
-	{[]int{0x41, 0x300, 0x40, 0x316}, []int{0x41, 0x300, 0x40, 0x316}},
+	{[]rune{'a'}, []rune{'a'}},
+	{[]rune{0x300}, []rune{0x300}},
+	{[]rune{0x300, 0x316}, []rune{0x316, 0x300}}, // CCC(0x300)==230; CCC(0x316)==220
+	{[]rune{0x316, 0x300}, []rune{0x316, 0x300}},
+	{[]rune{0x41, 0x316, 0x300}, []rune{0x41, 0x316, 0x300}},
+	{[]rune{0x41, 0x300, 0x316}, []rune{0x41, 0x316, 0x300}},
+	{[]rune{0x300, 0x316, 0x41}, []rune{0x316, 0x300, 0x41}},
+	{[]rune{0x41, 0x300, 0x40, 0x316}, []rune{0x41, 0x300, 0x40, 0x316}},
 }
 
 func TestInsert(t *testing.T) {
@@ -91,18 +91,18 @@ func TestInsert(t *testing.T) {
 }
 
 var decompositionNFDTest = []TestCase{
-	{[]int{0xC0}, []int{0x41, 0x300}},
-	{[]int{0xAC00}, []int{0x1100, 0x1161}},
-	{[]int{0x01C4}, []int{0x01C4}},
-	{[]int{0x320E}, []int{0x320E}},
-	{[]int("음ẻ과"), []int{0x110B, 0x1173, 0x11B7, 0x65, 0x309, 0x1100, 0x116A}},
+	{[]rune{0xC0}, []rune{0x41, 0x300}},
+	{[]rune{0xAC00}, []rune{0x1100, 0x1161}},
+	{[]rune{0x01C4}, []rune{0x01C4}},
+	{[]rune{0x320E}, []rune{0x320E}},
+	{[]rune("음ẻ과"), []rune{0x110B, 0x1173, 0x11B7, 0x65, 0x309, 0x1100, 0x116A}},
 }
 
 var decompositionNFKDTest = []TestCase{
-	{[]int{0xC0}, []int{0x41, 0x300}},
-	{[]int{0xAC00}, []int{0x1100, 0x1161}},
-	{[]int{0x01C4}, []int{0x44, 0x5A, 0x030C}},
-	{[]int{0x320E}, []int{0x28, 0x1100, 0x1161, 0x29}},
+	{[]rune{0xC0}, []rune{0x41, 0x300}},
+	{[]rune{0xAC00}, []rune{0x1100, 0x1161}},
+	{[]rune{0x01C4}, []rune{0x44, 0x5A, 0x030C}},
+	{[]rune{0x320E}, []rune{0x28, 0x1100, 0x1161, 0x29}},
 }
 
 func TestDecomposition(t *testing.T) {
@@ -111,15 +111,15 @@ func TestDecomposition(t *testing.T) {
 }
 
 var compositionTest = []TestCase{
-	{[]int{0x41, 0x300}, []int{0xC0}},
-	{[]int{0x41, 0x316}, []int{0x41, 0x316}},
-	{[]int{0x41, 0x300, 0x35D}, []int{0xC0, 0x35D}},
-	{[]int{0x41, 0x316, 0x300}, []int{0xC0, 0x316}},
+	{[]rune{0x41, 0x300}, []rune{0xC0}},
+	{[]rune{0x41, 0x316}, []rune{0x41, 0x316}},
+	{[]rune{0x41, 0x300, 0x35D}, []rune{0xC0, 0x35D}},
+	{[]rune{0x41, 0x316, 0x300}, []rune{0xC0, 0x316}},
 	// blocking starter
-	{[]int{0x41, 0x316, 0x40, 0x300}, []int{0x41, 0x316, 0x40, 0x300}},
-	{[]int{0x1100, 0x1161}, []int{0xAC00}},
+	{[]rune{0x41, 0x316, 0x40, 0x300}, []rune{0x41, 0x316, 0x40, 0x300}},
+	{[]rune{0x1100, 0x1161}, []rune{0xAC00}},
 	// parenthesized Hangul, alternate between ASCII and Hangul.
-	{[]int{0x28, 0x1100, 0x1161, 0x29}, []int{0x28, 0xAC00, 0x29}},
+	{[]rune{0x28, 0x1100, 0x1161, 0x29}, []rune{0x28, 0xAC00, 0x29}},
 }
 
 func TestComposition(t *testing.T) {
diff --git a/libgo/go/exp/norm/maketables.go b/libgo/go/exp/norm/maketables.go
index 14718c5..93edf22 100644
--- a/libgo/go/exp/norm/maketables.go
+++ b/libgo/go/exp/norm/maketables.go
@@ -119,7 +119,7 @@ const (
 // This contains only the properties we're interested in.
 type Char struct {
 	name          string
-	codePoint     int   // if zero, this index is not a valid code point.
+	codePoint     rune  // if zero, this index is not a valid code point.
 	ccc           uint8 // canonical combining class
 	excludeInComp bool  // from CompositionExclusions.txt
 	compatDecomp  bool  // it has a compatibility expansion
@@ -160,7 +160,7 @@ const (
 	SMissing
 )
 
-var lastChar int = 0
+var lastChar = rune('\u0000')
 
 func (c Char) isValid() bool {
 	return c.codePoint != 0 && c.state != SMissing
@@ -193,7 +193,7 @@ func (f FormInfo) String() string {
 	return buf.String()
 }
 
-type Decomposition []int
+type Decomposition []rune
 
 func (d Decomposition) String() string {
 	return fmt.Sprintf("%.4X", d)
@@ -220,7 +220,7 @@ func openReader(file string) (input io.ReadCloser) {
 	return
 }
 
-func parseDecomposition(s string, skipfirst bool) (a []int, e os.Error) {
+func parseDecomposition(s string, skipfirst bool) (a []rune, e os.Error) {
 	decomp := strings.Split(s, " ")
 	if len(decomp) > 0 && skipfirst {
 		decomp = decomp[1:]
@@ -230,7 +230,7 @@ func parseDecomposition(s string, skipfirst bool) (a []int, e os.Error) {
 		if err != nil {
 			return a, err
 		}
-		a = append(a, int(point))
+		a = append(a, rune(point))
 	}
 	return a, nil
 }
@@ -260,7 +260,7 @@ func parseCharacter(line string) {
 		state = SLast
 	}
 	firstChar := lastChar + 1
-	lastChar = int(point)
+	lastChar = rune(point)
 	if state != SLast {
 		firstChar = lastChar
 	}
@@ -370,8 +370,8 @@ func loadCompositionExclusions() {
 // hasCompatDecomp returns true if any of the recursive
 // decompositions contains a compatibility expansion.
 // In this case, the character may not occur in NFK*.
-func hasCompatDecomp(rune int) bool {
-	c := &chars[rune]
+func hasCompatDecomp(r rune) bool {
+	c := &chars[r]
 	if c.compatDecomp {
 		return true
 	}
@@ -396,19 +396,19 @@ const (
 	JamoTEnd  = 0x11C3
 )
 
-func isHangul(rune int) bool {
-	return HangulBase <= rune && rune < HangulEnd
+func isHangul(r rune) bool {
+	return HangulBase <= r && r < HangulEnd
 }
 
-func ccc(rune int) uint8 {
-	return chars[rune].ccc
+func ccc(r rune) uint8 {
+	return chars[r].ccc
 }
 
 // Insert a rune in a buffer, ordered by Canonical Combining Class.
-func insertOrdered(b Decomposition, rune int) Decomposition {
+func insertOrdered(b Decomposition, r rune) Decomposition {
 	n := len(b)
 	b = append(b, 0)
-	cc := ccc(rune)
+	cc := ccc(r)
 	if cc > 0 {
 		// Use bubble sort.
 		for ; n > 0; n-- {
@@ -418,18 +418,18 @@ func insertOrdered(b Decomposition, rune int) Decomposition {
 			b[n] = b[n-1]
 		}
 	}
-	b[n] = rune
+	b[n] = r
 	return b
 }
 
 // Recursively decompose.
-func decomposeRecursive(form int, rune int, d Decomposition) Decomposition {
-	if isHangul(rune) {
+func decomposeRecursive(form int, r rune, d Decomposition) Decomposition {
+	if isHangul(r) {
 		return d
 	}
-	dcomp := chars[rune].forms[form].decomp
+	dcomp := chars[r].forms[form].decomp
 	if len(dcomp) == 0 {
-		return insertOrdered(d, rune)
+		return insertOrdered(d, r)
 	}
 	for _, c := range dcomp {
 		d = decomposeRecursive(form, c, d)
@@ -475,8 +475,8 @@ func completeCharFields(form int) {
 			f.isOneWay = f.isOneWay || hasCompatDecomp(c.codePoint)
 		}
 
-		for _, rune := range f.decomp {
-			chars[rune].forms[form].inDecomp = true
+		for _, r := range f.decomp {
+			chars[r].forms[form].inDecomp = true
 		}
 	}
 
@@ -505,7 +505,7 @@ func completeCharFields(form int) {
 		switch {
 		case len(f.decomp) > 0:
 			f.quickCheck[MDecomposed] = QCNo
-		case isHangul(i):
+		case isHangul(rune(i)):
 			f.quickCheck[MDecomposed] = QCNo
 		default:
 			f.quickCheck[MDecomposed] = QCYes
@@ -588,7 +588,7 @@ func printCharInfoTables() int {
 	for i, char := range chars {
 		v := makeCharInfo(char)
 		if v != 0 {
-			t.insert(i, v)
+			t.insert(rune(i), v)
 		}
 	}
 	return t.printTables("charInfo")
@@ -606,7 +606,7 @@ func printDecompositionTables() int {
 	for _, c := range chars {
 		for f := 0; f < 2; f++ {
 			d := c.forms[f].expandedDecomp
-			s := string([]int(d))
+			s := string([]rune(d))
 			if _, ok := positionMap[s]; !ok {
 				p := decompositions.Len()
 				decompositions.WriteByte(uint8(len(s)))
@@ -624,7 +624,7 @@ func printDecompositionTables() int {
 	for i, c := range chars {
 		d := c.forms[FCanonical].expandedDecomp
 		if len(d) != 0 {
-			nfcT.insert(i, positionMap[string([]int(d))])
+			nfcT.insert(rune(i), positionMap[string([]rune(d))])
 			if ccc(c.codePoint) != ccc(d[0]) {
 				// We assume the lead ccc of a decomposition is !=0 in this case.
 				if ccc(d[0]) == 0 {
@@ -634,7 +634,7 @@ func printDecompositionTables() int {
 		}
 		d = c.forms[FCompatibility].expandedDecomp
 		if len(d) != 0 {
-			nfkcT.insert(i, positionMap[string([]int(d))])
+			nfkcT.insert(rune(i), positionMap[string([]rune(d))])
 			if ccc(c.codePoint) != ccc(d[0]) {
 				// We assume the lead ccc of a decomposition is !=0 in this case.
 				if ccc(d[0]) == 0 {
@@ -752,7 +752,7 @@ func verifyComputed() {
 	for i, c := range chars {
 		for _, f := range c.forms {
 			isNo := (f.quickCheck[MDecomposed] == QCNo)
-			if (len(f.decomp) > 0) != isNo && !isHangul(i) {
+			if (len(f.decomp) > 0) != isNo && !isHangul(rune(i)) {
 				log.Fatalf("%U: NF*D must be no if rune decomposes", i)
 			}
 
@@ -764,7 +764,7 @@ func verifyComputed() {
 	}
 }
 
-var qcRe = regexp.MustCompile(`^([0-9A-F\.]+) *; (NF.*_QC); ([YNM]) #.*$`)
+var qcRe = regexp.MustCompile(`([0-9A-F\.]+) *; (NF.*_QC); ([YNM]) #.*`)
 
 // Use values in DerivedNormalizationProps.txt to compare against the
 // values we computed.
diff --git a/libgo/go/exp/norm/maketesttables.go b/libgo/go/exp/norm/maketesttables.go
index fdcc114..20eb889 100644
--- a/libgo/go/exp/norm/maketesttables.go
+++ b/libgo/go/exp/norm/maketesttables.go
@@ -16,7 +16,7 @@ func main() {
 
 // We take the smallest, largest and an arbitrary value for each 
 // of the UTF-8 sequence lengths.
-var testRunes = []int{
+var testRunes = []rune{
 	0x01, 0x0C, 0x7F, // 1-byte sequences
 	0x80, 0x100, 0x7FF, // 2-byte sequences
 	0x800, 0x999, 0xFFFF, // 3-byte sequences
diff --git a/libgo/go/exp/norm/normalize_test.go b/libgo/go/exp/norm/normalize_test.go
index e374edf..6bd5292 100644
--- a/libgo/go/exp/norm/normalize_test.go
+++ b/libgo/go/exp/norm/normalize_test.go
@@ -28,13 +28,13 @@ func runPosTests(t *testing.T, name string, f Form, fn positionFunc, tests []Pos
 		if pos != test.pos {
 			t.Errorf("%s:%d: position is %d; want %d", name, i, pos, test.pos)
 		}
-		runes := []int(test.buffer)
+		runes := []rune(test.buffer)
 		if rb.nrune != len(runes) {
 			t.Errorf("%s:%d: reorder buffer lenght is %d; want %d", name, i, rb.nrune, len(runes))
 			continue
 		}
 		for j, want := range runes {
-			found := int(rb.runeAt(j))
+			found := rune(rb.runeAt(j))
 			if found != want {
 				t.Errorf("%s:%d: rune at %d is %U; want %U", name, i, j, found, want)
 			}
@@ -385,8 +385,8 @@ func runAppendTests(t *testing.T, name string, f Form, fn appendFunc, tests []Ap
 		}
 		if outs != test.out {
 			// Find first rune that differs and show context.
-			ir := []int(outs)
-			ig := []int(test.out)
+			ir := []rune(outs)
+			ig := []rune(test.out)
 			for j := 0; j < len(ir) && j < len(ig); j++ {
 				if ir[j] == ig[j] {
 					continue
diff --git a/libgo/go/exp/norm/normregtest.go b/libgo/go/exp/norm/normregtest.go
index cbd73ff..e747dde 100644
--- a/libgo/go/exp/norm/normregtest.go
+++ b/libgo/go/exp/norm/normregtest.go
@@ -16,8 +16,8 @@ import (
 	"path"
 	"regexp"
 	"runtime"
-	"strings"
 	"strconv"
+	"strings"
 	"time"
 	"utf8"
 )
@@ -103,7 +103,7 @@ type Test struct {
 	name   string
 	partnr int
 	number int
-	rune   int                 // used for character by character test
+	r      rune                // used for character by character test
 	cols   [cMaxColumns]string // Each has 5 entries, see below.
 }
 
@@ -174,12 +174,12 @@ func loadTestData() {
 				if err != nil {
 					logger.Fatal(err)
 				}
-				if test.rune == 0 {
+				if test.r == 0 {
 					// save for CharacterByCharacterTests
-					test.rune = int(r)
+					test.r = int(r)
 				}
 				var buf [utf8.UTFMax]byte
-				sz := utf8.EncodeRune(buf[:], int(r))
+				sz := utf8.EncodeRune(buf[:], rune(r))
 				test.cols[j-1] += string(buf[:sz])
 			}
 		}
@@ -198,7 +198,7 @@ func cmpResult(t *Test, name string, f norm.Form, gold, test, result string) {
 		if errorCount > 20 {
 			return
 		}
-		st, sr, sg := []int(test), []int(result), []int(gold)
+		st, sr, sg := []rune(test), []rune(result), []rune(gold)
 		logger.Printf("%s:%s: %s(%X)=%X; want:%X: %s",
 			t.Name(), name, fstr[f], st, sr, sg, t.name)
 	}
@@ -210,7 +210,7 @@ func cmpIsNormal(t *Test, name string, f norm.Form, test string, result, want bo
 		if errorCount > 20 {
 			return
 		}
-		logger.Printf("%s:%s: %s(%X)=%v; want: %v", t.Name(), name, fstr[f], []int(test), result, want)
+		logger.Printf("%s:%s: %s(%X)=%v; want: %v", t.Name(), name, fstr[f], []rune(test), result, want)
 	}
 }
 
@@ -243,13 +243,13 @@ func CharacterByCharacterTests() {
 	tests := part[1].tests
 	last := 0
 	for i := 0; i <= len(tests); i++ { // last one is special case
-		var rune int
+		var r int
 		if i == len(tests) {
-			rune = 0x2FA1E // Don't have to go to 0x10FFFF
+			r = 0x2FA1E // Don't have to go to 0x10FFFF
 		} else {
-			rune = tests[i].rune
+			r = tests[i].r
 		}
-		for last++; last < rune; last++ {
+		for last++; last < r; last++ {
 			// Check all characters that were not explicitly listed in the test.
 			t := &Test{partnr: 1, number: -1}
 			char := string(last)
diff --git a/libgo/go/exp/norm/trie_test.go b/libgo/go/exp/norm/trie_test.go
index 5649fb7..bbd5c03 100644
--- a/libgo/go/exp/norm/trie_test.go
+++ b/libgo/go/exp/norm/trie_test.go
@@ -73,15 +73,15 @@ var tests = []trietest{
 	{1, []byte{t6, tx, tx, tx, tx, tx}},
 }
 
-func mkUtf8(rune int) ([]byte, int) {
+func mkUTF8(r rune) ([]byte, int) {
 	var b [utf8.UTFMax]byte
-	sz := utf8.EncodeRune(b[:], rune)
+	sz := utf8.EncodeRune(b[:], r)
 	return b[:sz], sz
 }
 
 func TestLookup(t *testing.T) {
 	for i, tt := range testRunes {
-		b, szg := mkUtf8(tt)
+		b, szg := mkUTF8(tt)
 		v, szt := testdata.lookup(b)
 		if int(v) != i {
 			t.Errorf("lookup(%U): found value %#x, expected %#x", tt, v, i)
@@ -103,7 +103,7 @@ func TestLookup(t *testing.T) {
 
 func TestLookupUnsafe(t *testing.T) {
 	for i, tt := range testRunes {
-		b, _ := mkUtf8(tt)
+		b, _ := mkUTF8(tt)
 		v := testdata.lookupUnsafe(b)
 		if int(v) != i {
 			t.Errorf("lookupUnsafe(%U): found value %#x, expected %#x", i, v, i)
@@ -113,7 +113,7 @@ func TestLookupUnsafe(t *testing.T) {
 
 func TestLookupString(t *testing.T) {
 	for i, tt := range testRunes {
-		b, szg := mkUtf8(tt)
+		b, szg := mkUTF8(tt)
 		v, szt := testdata.lookupString(string(b))
 		if int(v) != i {
 			t.Errorf("lookup(%U): found value %#x, expected %#x", i, v, i)
@@ -135,7 +135,7 @@ func TestLookupString(t *testing.T) {
 
 func TestLookupStringUnsafe(t *testing.T) {
 	for i, tt := range testRunes {
-		b, _ := mkUtf8(tt)
+		b, _ := mkUTF8(tt)
 		v := testdata.lookupStringUnsafe(string(b))
 		if int(v) != i {
 			t.Errorf("lookupUnsafe(%U): found value %#x, expected %#x", i, v, i)
diff --git a/libgo/go/exp/norm/triedata_test.go b/libgo/go/exp/norm/triedata_test.go
index e8898e5..7f62760 100644
--- a/libgo/go/exp/norm/triedata_test.go
+++ b/libgo/go/exp/norm/triedata_test.go
@@ -4,7 +4,7 @@
 
 package norm
 
-var testRunes = []int{1, 12, 127, 128, 256, 2047, 2048, 2457, 65535, 65536, 65793, 1114111, 512, 513, 514, 528, 533}
+var testRunes = []rune{1, 12, 127, 128, 256, 2047, 2048, 2457, 65535, 65536, 65793, 1114111, 512, 513, 514, 528, 533}
 
 // testdataValues: 192 entries, 384 bytes
 // Block 2 is the null block.
diff --git a/libgo/go/exp/norm/triegen.go b/libgo/go/exp/norm/triegen.go
index 515e1c7..56cba32 100644
--- a/libgo/go/exp/norm/triegen.go
+++ b/libgo/go/exp/norm/triegen.go
@@ -94,9 +94,9 @@ func (n trieNode) countSparseEntries() int {
 	return count
 }
 
-func (n *trieNode) insert(rune int, value uint16) {
+func (n *trieNode) insert(r rune, value uint16) {
 	var p [utf8.UTFMax]byte
-	sz := utf8.EncodeRune(p[:], rune)
+	sz := utf8.EncodeRune(p[:], r)
 
 	for i := 0; i < sz; i++ {
 		if n.leaf {
diff --git a/libgo/go/exp/sql/convert_test.go b/libgo/go/exp/sql/convert_test.go
index 88ba8e7..8499918 100644
--- a/libgo/go/exp/sql/convert_test.go
+++ b/libgo/go/exp/sql/convert_test.go
@@ -52,7 +52,7 @@ var conversionTests = []conversionTest{
 	{s: "256", d: &scanuint8, wanterr: `string "256" overflows uint8`},
 	{s: "256", d: &scanuint16, wantuint: 256},
 	{s: "-1", d: &scanint, wantint: -1},
-	{s: "foo", d: &scanint, wanterr: `converting string "foo" to a int: parsing "foo": Invalid argument`},
+	{s: "foo", d: &scanint, wanterr: `converting string "foo" to a int: parsing "foo": invalid syntax`},
 }
 
 func intValue(intptr interface{}) int64 {
diff --git a/libgo/go/exp/ssh/client.go b/libgo/go/exp/ssh/client.go
index 3311385..9eed315 100644
--- a/libgo/go/exp/ssh/client.go
+++ b/libgo/go/exp/ssh/client.go
@@ -258,51 +258,71 @@ func (c *ClientConn) openChan(typ string) (*clientChan, os.Error) {
 // mainloop reads incoming messages and routes channel messages
 // to their respective ClientChans.
 func (c *ClientConn) mainLoop() {
+	// TODO(dfc) signal the underlying close to all channels
+	defer c.Close()
 	for {
 		packet, err := c.readPacket()
 		if err != nil {
-			// TODO(dfc) signal the underlying close to all channels
-			c.Close()
-			return
+			break
 		}
 		// TODO(dfc) A note on blocking channel use. 
 		// The msg, win, data and dataExt channels of a clientChan can 
 		// cause this loop to block indefinately if the consumer does 
 		// not service them. 
-		switch msg := decode(packet).(type) {
-		case *channelOpenMsg:
-			c.getChan(msg.PeersId).msg <- msg
-		case *channelOpenConfirmMsg:
-			c.getChan(msg.PeersId).msg <- msg
-		case *channelOpenFailureMsg:
-			c.getChan(msg.PeersId).msg <- msg
-		case *channelCloseMsg:
-			ch := c.getChan(msg.PeersId)
-			close(ch.win)
-			close(ch.data)
-			close(ch.dataExt)
-			c.chanlist.remove(msg.PeersId)
-		case *channelEOFMsg:
-			c.getChan(msg.PeersId).msg <- msg
-		case *channelRequestSuccessMsg:
-			c.getChan(msg.PeersId).msg <- msg
-		case *channelRequestFailureMsg:
-			c.getChan(msg.PeersId).msg <- msg
-		case *channelRequestMsg:
-			c.getChan(msg.PeersId).msg <- msg
-		case *windowAdjustMsg:
-			c.getChan(msg.PeersId).win <- int(msg.AdditionalBytes)
-		case *channelData:
-			c.getChan(msg.PeersId).data <- msg.Payload
-		case *channelExtendedData:
-			// RFC 4254 5.2 defines data_type_code 1 to be data destined 
-			// for stderr on interactive sessions. Other data types are
-			// silently discarded.
-			if msg.Datatype == 1 {
-				c.getChan(msg.PeersId).dataExt <- msg.Payload
+		switch packet[0] {
+		case msgChannelData:
+			if len(packet) < 9 {
+				// malformed data packet
+				break
+			}
+			peersId := uint32(packet[1])<<24 | uint32(packet[2])<<16 | uint32(packet[3])<<8 | uint32(packet[4])
+			if length := int(packet[5])<<24 | int(packet[6])<<16 | int(packet[7])<<8 | int(packet[8]); length > 0 {
+				packet = packet[9:]
+				c.getChan(peersId).data <- packet[:length]
+			}
+		case msgChannelExtendedData:
+			if len(packet) < 13 {
+				// malformed data packet
+				break
+			}
+			peersId := uint32(packet[1])<<24 | uint32(packet[2])<<16 | uint32(packet[3])<<8 | uint32(packet[4])
+			datatype := uint32(packet[5])<<24 | uint32(packet[6])<<16 | uint32(packet[7])<<8 | uint32(packet[8])
+			if length := int(packet[9])<<24 | int(packet[10])<<16 | int(packet[11])<<8 | int(packet[12]); length > 0 {
+				packet = packet[13:]
+				// RFC 4254 5.2 defines data_type_code 1 to be data destined 
+				// for stderr on interactive sessions. Other data types are
+				// silently discarded.
+				if datatype == 1 {
+					c.getChan(peersId).dataExt <- packet[:length]
+				}
 			}
 		default:
-			fmt.Printf("mainLoop: unhandled %#v\n", msg)
+			switch msg := decode(packet).(type) {
+			case *channelOpenMsg:
+				c.getChan(msg.PeersId).msg <- msg
+			case *channelOpenConfirmMsg:
+				c.getChan(msg.PeersId).msg <- msg
+			case *channelOpenFailureMsg:
+				c.getChan(msg.PeersId).msg <- msg
+			case *channelCloseMsg:
+				ch := c.getChan(msg.PeersId)
+				close(ch.win)
+				close(ch.data)
+				close(ch.dataExt)
+				c.chanlist.remove(msg.PeersId)
+			case *channelEOFMsg:
+				c.getChan(msg.PeersId).msg <- msg
+			case *channelRequestSuccessMsg:
+				c.getChan(msg.PeersId).msg <- msg
+			case *channelRequestFailureMsg:
+				c.getChan(msg.PeersId).msg <- msg
+			case *channelRequestMsg:
+				c.getChan(msg.PeersId).msg <- msg
+			case *windowAdjustMsg:
+				c.getChan(msg.PeersId).win <- int(msg.AdditionalBytes)
+			default:
+				fmt.Printf("mainLoop: unhandled %#v\n", msg)
+			}
 		}
 	}
 }
diff --git a/libgo/go/exp/ssh/messages.go b/libgo/go/exp/ssh/messages.go
index 7771f2b..5f2c447 100644
--- a/libgo/go/exp/ssh/messages.go
+++ b/libgo/go/exp/ssh/messages.go
@@ -144,19 +144,6 @@ type channelOpenFailureMsg struct {
 	Language string
 }
 
-// See RFC 4254, section 5.2.
-type channelData struct {
-	PeersId uint32
-	Payload []byte `ssh:"rest"`
-}
-
-// See RFC 4254, section 5.2.
-type channelExtendedData struct {
-	PeersId  uint32
-	Datatype uint32
-	Payload  []byte `ssh:"rest"`
-}
-
 type channelRequestMsg struct {
 	PeersId             uint32
 	Request             string
@@ -612,10 +599,6 @@ func decode(packet []byte) interface{} {
 		msg = new(channelOpenFailureMsg)
 	case msgChannelWindowAdjust:
 		msg = new(windowAdjustMsg)
-	case msgChannelData:
-		msg = new(channelData)
-	case msgChannelExtendedData:
-		msg = new(channelExtendedData)
 	case msgChannelEOF:
 		msg = new(channelEOFMsg)
 	case msgChannelClose:
diff --git a/libgo/go/exp/ssh/server.go b/libgo/go/exp/ssh/server.go
index 3a640fc..0dd24ec 100644
--- a/libgo/go/exp/ssh/server.go
+++ b/libgo/go/exp/ssh/server.go
@@ -581,75 +581,89 @@ func (s *ServerConn) Accept() (Channel, os.Error) {
 			return nil, err
 		}
 
-		switch msg := decode(packet).(type) {
-		case *channelOpenMsg:
-			c := new(channel)
-			c.chanType = msg.ChanType
-			c.theirId = msg.PeersId
-			c.theirWindow = msg.PeersWindow
-			c.maxPacketSize = msg.MaxPacketSize
-			c.extraData = msg.TypeSpecificData
-			c.myWindow = defaultWindowSize
-			c.serverConn = s
-			c.cond = sync.NewCond(&c.lock)
-			c.pendingData = make([]byte, c.myWindow)
-
-			s.lock.Lock()
-			c.myId = s.nextChanId
-			s.nextChanId++
-			s.channels[c.myId] = c
-			s.lock.Unlock()
-			return c, nil
-
-		case *channelRequestMsg:
-			s.lock.Lock()
-			c, ok := s.channels[msg.PeersId]
-			if !ok {
-				continue
+		switch packet[0] {
+		case msgChannelData:
+			if len(packet) < 9 {
+				// malformed data packet
+				return nil, ParseError{msgChannelData}
 			}
-			c.handlePacket(msg)
-			s.lock.Unlock()
-
-		case *channelData:
+			peersId := uint32(packet[1])<<24 | uint32(packet[2])<<16 | uint32(packet[3])<<8 | uint32(packet[4])
 			s.lock.Lock()
-			c, ok := s.channels[msg.PeersId]
+			c, ok := s.channels[peersId]
 			if !ok {
+				s.lock.Unlock()
 				continue
 			}
-			c.handleData(msg.Payload)
-			s.lock.Unlock()
-
-		case *channelEOFMsg:
-			s.lock.Lock()
-			c, ok := s.channels[msg.PeersId]
-			if !ok {
-				continue
+			if length := int(packet[5])<<24 | int(packet[6])<<16 | int(packet[7])<<8 | int(packet[8]); length > 0 {
+				packet = packet[9:]
+				c.handleData(packet[:length])
 			}
-			c.handlePacket(msg)
 			s.lock.Unlock()
+		default:
+			switch msg := decode(packet).(type) {
+			case *channelOpenMsg:
+				c := new(channel)
+				c.chanType = msg.ChanType
+				c.theirId = msg.PeersId
+				c.theirWindow = msg.PeersWindow
+				c.maxPacketSize = msg.MaxPacketSize
+				c.extraData = msg.TypeSpecificData
+				c.myWindow = defaultWindowSize
+				c.serverConn = s
+				c.cond = sync.NewCond(&c.lock)
+				c.pendingData = make([]byte, c.myWindow)
+
+				s.lock.Lock()
+				c.myId = s.nextChanId
+				s.nextChanId++
+				s.channels[c.myId] = c
+				s.lock.Unlock()
+				return c, nil
+
+			case *channelRequestMsg:
+				s.lock.Lock()
+				c, ok := s.channels[msg.PeersId]
+				if !ok {
+					s.lock.Unlock()
+					continue
+				}
+				c.handlePacket(msg)
+				s.lock.Unlock()
 
-		case *channelCloseMsg:
-			s.lock.Lock()
-			c, ok := s.channels[msg.PeersId]
-			if !ok {
-				continue
-			}
-			c.handlePacket(msg)
-			s.lock.Unlock()
+			case *channelEOFMsg:
+				s.lock.Lock()
+				c, ok := s.channels[msg.PeersId]
+				if !ok {
+					s.lock.Unlock()
+					continue
+				}
+				c.handlePacket(msg)
+				s.lock.Unlock()
 
-		case *globalRequestMsg:
-			if msg.WantReply {
-				if err := s.writePacket([]byte{msgRequestFailure}); err != nil {
-					return nil, err
+			case *channelCloseMsg:
+				s.lock.Lock()
+				c, ok := s.channels[msg.PeersId]
+				if !ok {
+					s.lock.Unlock()
+					continue
 				}
-			}
+				c.handlePacket(msg)
+				s.lock.Unlock()
 
-		case UnexpectedMessageError:
-			return nil, msg
-		case *disconnectMsg:
-			return nil, os.EOF
-		default:
-			// Unknown message. Ignore.
+			case *globalRequestMsg:
+				if msg.WantReply {
+					if err := s.writePacket([]byte{msgRequestFailure}); err != nil {
+						return nil, err
+					}
+				}
+
+			case UnexpectedMessageError:
+				return nil, msg
+			case *disconnectMsg:
+				return nil, os.EOF
+			default:
+				// Unknown message. Ignore.
+			}
 		}
 	}
 
diff --git a/libgo/go/exp/template/html/css.go b/libgo/go/exp/template/html/css.go
index c22ec6d..c26ae78 100644
--- a/libgo/go/exp/template/html/css.go
+++ b/libgo/go/exp/template/html/css.go
@@ -35,19 +35,19 @@ func endsWithCSSKeyword(b []byte, kw string) bool {
 }
 
 // isCSSNmchar returns whether rune is allowed anywhere in a CSS identifier.
-func isCSSNmchar(rune int) bool {
+func isCSSNmchar(r rune) bool {
 	// Based on the CSS3 nmchar production but ignores multi-rune escape
 	// sequences.
 	// http://www.w3.org/TR/css3-syntax/#SUBTOK-nmchar
-	return 'a' <= rune && rune <= 'z' ||
-		'A' <= rune && rune <= 'Z' ||
-		'0' <= rune && rune <= '9' ||
-		'-' == rune ||
-		'_' == rune ||
+	return 'a' <= r && r <= 'z' ||
+		'A' <= r && r <= 'Z' ||
+		'0' <= r && r <= '9' ||
+		r == '-' ||
+		r == '_' ||
 		// Non-ASCII cases below.
-		0x80 <= rune && rune <= 0xd7ff ||
-		0xe000 <= rune && rune <= 0xfffd ||
-		0x10000 <= rune && rune <= 0x10ffff
+		0x80 <= r && r <= 0xd7ff ||
+		0xe000 <= r && r <= 0xfffd ||
+		0x10000 <= r && r <= 0x10ffff
 }
 
 // decodeCSS decodes CSS3 escapes given a sequence of stringchars.
@@ -81,11 +81,11 @@ func decodeCSS(s []byte) []byte {
 			for j < len(s) && j < 7 && isHex(s[j]) {
 				j++
 			}
-			rune := hexDecode(s[1:j])
-			if rune > unicode.MaxRune {
-				rune, j = rune/16, j-1
+			r := hexDecode(s[1:j])
+			if r > unicode.MaxRune {
+				r, j = r/16, j-1
 			}
-			n := utf8.EncodeRune(b[len(b):cap(b)], rune)
+			n := utf8.EncodeRune(b[len(b):cap(b)], r)
 			// The optional space at the end allows a hex
 			// sequence to be followed by a literal hex.
 			// string(decodeCSS([]byte(`\A B`))) == "\nB"
@@ -105,17 +105,17 @@ func isHex(c byte) bool {
 }
 
 // hexDecode decodes a short hex digit sequence: "10" -> 16.
-func hexDecode(s []byte) int {
-	n := 0
+func hexDecode(s []byte) rune {
+	n := rune(0)
 	for _, c := range s {
 		n <<= 4
 		switch {
 		case '0' <= c && c <= '9':
-			n |= int(c - '0')
+			n |= rune(c - '0')
 		case 'a' <= c && c <= 'f':
-			n |= int(c-'a') + 10
+			n |= rune(c-'a') + 10
 		case 'A' <= c && c <= 'F':
-			n |= int(c-'A') + 10
+			n |= rune(c-'A') + 10
 		default:
 			panic(fmt.Sprintf("Bad hex digit in %q", s))
 		}
@@ -251,11 +251,11 @@ func cssValueFilter(args ...interface{}) string {
 		case '-':
 			// Disallow <!-- or -->.
 			// -- should not appear in valid identifiers.
-			if i != 0 && '-' == b[i-1] {
+			if i != 0 && b[i-1] == '-' {
 				return filterFailsafe
 			}
 		default:
-			if c < 0x80 && isCSSNmchar(int(c)) {
+			if c < 0x80 && isCSSNmchar(rune(c)) {
 				id = append(id, c)
 			}
 		}
diff --git a/libgo/go/exp/template/html/css_test.go b/libgo/go/exp/template/html/css_test.go
index 5f633e8..b3b83e8 100644
--- a/libgo/go/exp/template/html/css_test.go
+++ b/libgo/go/exp/template/html/css_test.go
@@ -35,7 +35,7 @@ func TestEndsWithCSSKeyword(t *testing.T) {
 
 func TestIsCSSNmchar(t *testing.T) {
 	tests := []struct {
-		rune int
+		rune rune
 		want bool
 	}{
 		{0, false},
@@ -114,11 +114,11 @@ func TestDecodeCSS(t *testing.T) {
 func TestHexDecode(t *testing.T) {
 	for i := 0; i < 0x200000; i += 101 /* coprime with 16 */ {
 		s := strconv.Itob(i, 16)
-		if got := hexDecode([]byte(s)); got != i {
+		if got := int(hexDecode([]byte(s))); got != i {
 			t.Errorf("%s: want %d but got %d", s, i, got)
 		}
 		s = strings.ToUpper(s)
-		if got := hexDecode([]byte(s)); got != i {
+		if got := int(hexDecode([]byte(s))); got != i {
 			t.Errorf("%s: want %d but got %d", s, i, got)
 		}
 	}
diff --git a/libgo/go/exp/template/html/escape_test.go b/libgo/go/exp/template/html/escape_test.go
index a4ea759..1b3b256 100644
--- a/libgo/go/exp/template/html/escape_test.go
+++ b/libgo/go/exp/template/html/escape_test.go
@@ -1549,8 +1549,8 @@ func TestEnsurePipelineContains(t *testing.T) {
 	}
 }
 
-func expectExecuteFailure(t *testing.T, b *bytes.Buffer) {
-	if x := recover(); x != nil {
+func expectExecuteFailure(t *testing.T, b *bytes.Buffer, err os.Error) {
+	if err != nil {
 		if b.Len() != 0 {
 			t.Errorf("output on buffer: %q", b.String())
 		}
@@ -1563,8 +1563,8 @@ func TestEscapeErrorsNotIgnorable(t *testing.T) {
 	var b bytes.Buffer
 	tmpl := template.Must(template.New("dangerous").Parse("<a"))
 	Escape(tmpl)
-	defer expectExecuteFailure(t, &b)
-	tmpl.Execute(&b, nil)
+	err := tmpl.Execute(&b, nil)
+	expectExecuteFailure(t, &b, err)
 }
 
 func TestEscapeSetErrorsNotIgnorable(t *testing.T) {
@@ -1574,8 +1574,8 @@ func TestEscapeSetErrorsNotIgnorable(t *testing.T) {
 	}
 	EscapeSet(s, "t")
 	var b bytes.Buffer
-	defer expectExecuteFailure(t, &b)
-	s.Execute(&b, "t", nil)
+	err = s.Execute(&b, "t", nil)
+	expectExecuteFailure(t, &b, err)
 }
 
 func TestRedundantFuncs(t *testing.T) {
diff --git a/libgo/go/exp/template/html/html.go b/libgo/go/exp/template/html/html.go
index 91bb1b1..92d8f41 100644
--- a/libgo/go/exp/template/html/html.go
+++ b/libgo/go/exp/template/html/html.go
@@ -139,7 +139,7 @@ var htmlNospaceNormReplacementTable = []string{
 func htmlReplacer(s string, replacementTable []string, badRunes bool) string {
 	written, b := 0, new(bytes.Buffer)
 	for i, r := range s {
-		if r < len(replacementTable) {
+		if int(r) < len(replacementTable) {
 			if repl := replacementTable[r]; len(repl) != 0 {
 				b.WriteString(s[written:i])
 				b.WriteString(repl)
diff --git a/libgo/go/exp/template/html/js.go b/libgo/go/exp/template/html/js.go
index 98c2ac5..5646f8a 100644
--- a/libgo/go/exp/template/html/js.go
+++ b/libgo/go/exp/template/html/js.go
@@ -85,7 +85,7 @@ func nextJSCtx(s []byte, preceding jsCtx) jsCtx {
 		// Look for an IdentifierName and see if it is a keyword that
 		// can precede a regular expression.
 		j := n
-		for j > 0 && isJSIdentPart(int(s[j-1])) {
+		for j > 0 && isJSIdentPart(rune(s[j-1])) {
 			j--
 		}
 		if regexpPrecederKeywords[string(s[j:])] {
@@ -234,7 +234,7 @@ func replace(s string, replacementTable []string) string {
 	for i, r := range s {
 		var repl string
 		switch {
-		case r < len(replacementTable) && replacementTable[r] != "":
+		case int(r) < len(replacementTable) && replacementTable[r] != "":
 			repl = replacementTable[r]
 		case r == '\u2028':
 			repl = `\u2028`
@@ -329,17 +329,17 @@ var jsRegexpReplacementTable = []string{
 // It does not handle all the non-Latin letters, joiners, and combining marks,
 // but it does handle every codepoint that can occur in a numeric literal or
 // a keyword.
-func isJSIdentPart(rune int) bool {
+func isJSIdentPart(r rune) bool {
 	switch {
-	case '$' == rune:
+	case r == '$':
 		return true
-	case '0' <= rune && rune <= '9':
+	case '0' <= r && r <= '9':
 		return true
-	case 'A' <= rune && rune <= 'Z':
+	case 'A' <= r && r <= 'Z':
 		return true
-	case '_' == rune:
+	case r == '_':
 		return true
-	case 'a' <= rune && rune <= 'z':
+	case 'a' <= r && r <= 'z':
 		return true
 	}
 	return false
diff --git a/libgo/go/exp/types/exportdata.go b/libgo/go/exp/types/exportdata.go
index 3835203..784ffff 100644
--- a/libgo/go/exp/types/exportdata.go
+++ b/libgo/go/exp/types/exportdata.go
@@ -17,7 +17,7 @@ import (
 
 func readGopackHeader(buf *bufio.Reader) (name string, size int, err os.Error) {
 	// See $GOROOT/include/ar.h.
-	hdr := make([]byte, 64+12+6+6+8+10+2)
+	hdr := make([]byte, 16+12+6+6+8+10+2)
 	_, err = io.ReadFull(buf, hdr)
 	if err != nil {
 		return
@@ -25,13 +25,13 @@ func readGopackHeader(buf *bufio.Reader) (name string, size int, err os.Error) {
 	if trace {
 		fmt.Printf("header: %s", hdr)
 	}
-	s := strings.TrimSpace(string(hdr[64+12+6+6+8:][:10]))
+	s := strings.TrimSpace(string(hdr[16+12+6+6+8:][:10]))
 	size, err = strconv.Atoi(s)
 	if err != nil || hdr[len(hdr)-2] != '`' || hdr[len(hdr)-1] != '\n' {
 		err = os.NewError("invalid archive header")
 		return
 	}
-	name = strings.TrimSpace(string(hdr[:64]))
+	name = strings.TrimSpace(string(hdr[:16]))
 	return
 }
 
diff --git a/libgo/go/exp/types/gcimporter.go b/libgo/go/exp/types/gcimporter.go
index e744a63..4e5172a3 100644
--- a/libgo/go/exp/types/gcimporter.go
+++ b/libgo/go/exp/types/gcimporter.go
@@ -71,7 +71,7 @@ func findPkg(path string) (filename, id string) {
 // object/archive file and populates its scope with the results.
 type gcParser struct {
 	scanner scanner.Scanner
-	tok     int                    // current token
+	tok     rune                   // current token
 	lit     string                 // literal string; only valid for Ident, Int, String tokens
 	id      string                 // package id of imported package
 	imports map[string]*ast.Object // package id -> package object
@@ -195,7 +195,7 @@ func (p *gcParser) errorf(format string, args ...interface{}) {
 	p.error(fmt.Sprintf(format, args...))
 }
 
-func (p *gcParser) expect(tok int) string {
+func (p *gcParser) expect(tok rune) string {
 	lit := p.lit
 	if p.tok != tok {
 		p.errorf("expected %q, got %q (%q)", scanner.TokenString(tok), scanner.TokenString(p.tok), lit)
@@ -205,9 +205,9 @@ func (p *gcParser) expect(tok int) string {
 }
 
 func (p *gcParser) expectSpecial(tok string) {
-	sep := 'x' // not white space
+	sep := rune('x') // not white space
 	i := 0
-	for i < len(tok) && p.tok == int(tok[i]) && sep > ' ' {
+	for i < len(tok) && p.tok == rune(tok[i]) && sep > ' ' {
 		sep = p.scanner.Peek() // if sep <= ' ', there is white space before the next token
 		p.next()
 		i++
@@ -260,7 +260,7 @@ func (p *gcParser) parsePkgId() *ast.Object {
 func (p *gcParser) parseDotIdent() string {
 	ident := ""
 	if p.tok != scanner.Int {
-		sep := 'x' // not white space
+		sep := rune('x') // not white space
 		for (p.tok == scanner.Ident || p.tok == scanner.Int || p.tok == '·') && sep > ' ' {
 			ident += p.lit
 			sep = p.scanner.Peek() // if sep <= ' ', there is white space before the next token
diff --git a/libgo/go/exp/types/testdata/test0.src b/libgo/go/exp/types/testdata/test0.src
new file mode 100644
index 0000000..84a1abe
--- /dev/null
+++ b/libgo/go/exp/types/testdata/test0.src
@@ -0,0 +1,154 @@
+// Copyright 2011 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.
+
+// type declarations
+
+package test0
+
+import "unsafe"
+
+const pi = 3.1415
+
+type (
+	N undeclared /* ERROR "undeclared" */
+	B bool
+	I int32
+	A [10]P
+	T struct {
+		x, y P
+	}
+	P *T
+	R (*R)
+	F func(A) I
+	Y interface {
+		f(A) I
+	}
+	S [](((P)))
+	M map[I]F
+	C chan<- I
+)
+
+
+type (
+	p1 pi /* ERROR "not a package" */ .foo
+	p2 unsafe.Pointer
+)
+
+
+type (
+	Pi pi /* ERROR "not a type" */
+
+	a /* DISABLED "illegal cycle" */ a
+	a /* ERROR "redeclared" */ int
+
+	// where the cycle error appears depends on the
+	// order in which declarations are processed
+	// (which depends on the order in which a map
+	// is iterated through)
+	b c
+	c /* DISABLED "illegal cycle" */ d
+	d e
+	e b
+
+	t *t
+
+	U V
+	V *W
+	W U
+
+	P1 *S2
+	P2 P1
+
+	S0 struct {
+	}
+	S1 struct {
+		a, b, c int
+		u, v, a /* ERROR "redeclared" */ float32
+	}
+	S2 struct {
+		U // anonymous field
+		// TODO(gri) recognize double-declaration below
+		// U /* ERROR "redeclared" */ int
+	}
+	S3 struct {
+		x S2
+	}
+	S4/* DISABLED "illegal cycle" */ struct {
+		S4
+	}
+	S5 struct {
+		S6
+	}
+	S6 /* DISABLED "illegal cycle" */ struct {
+		field S7
+	}
+	S7 struct {
+		S5
+	}
+
+	L1 []L1
+	L2 []int
+
+	A1 [10]int
+	A2 /* DISABLED "illegal cycle" */ [10]A2
+	A3 /* DISABLED "illegal cycle" */ [10]struct {
+		x A4
+	}
+	A4 [10]A3
+
+	F1 func()
+	F2 func(x, y, z float32)
+	F3 func(x, y, x /* ERROR "redeclared" */ float32)
+	F4 func() (x, y, x /* ERROR "redeclared" */ float32)
+	F5 func(x int) (x /* ERROR "redeclared" */ float32)
+	F6 func(x ...int)
+
+	I1 interface{}
+	I2 interface {
+		m1()
+	}
+	I3 interface {
+		m1()
+		m1 /* ERROR "redeclared" */ ()
+	}
+	I4 interface {
+		m1(x, y, x /* ERROR "redeclared" */ float32)
+		m2() (x, y, x /* ERROR "redeclared" */ float32)
+		m3(x int) (x /* ERROR "redeclared" */ float32)
+	}
+	I5 interface {
+		m1(I5)
+	}
+	I6 interface {
+		S0 /* ERROR "non-interface" */
+	}
+	I7 interface {
+		I1
+		I1
+	}
+	I8 /* DISABLED "illegal cycle" */ interface {
+		I8
+	}
+	I9 /* DISABLED "illegal cycle" */ interface {
+		I10
+	}
+	I10 interface {
+		I11
+	}
+	I11 interface {
+		I9
+	}
+
+	C1 chan int
+	C2 <-chan int
+	C3 chan<- C3
+	C4 chan C5
+	C5 chan C6
+	C6 chan C4
+
+	M1 map[Last]string
+	M2 map[string]M2
+
+	Last int
+)
diff --git a/libgo/go/exp/types/universe.go b/libgo/go/exp/types/universe.go
index 80db127..f043596 100644
--- a/libgo/go/exp/types/universe.go
+++ b/libgo/go/exp/types/universe.go
@@ -54,6 +54,7 @@ func init() {
 
 	Bool = defType("bool")
 	defType("byte") // TODO(gri) should be an alias for uint8
+	defType("rune") // TODO(gri) should be an alias for int
 	defType("complex64")
 	Complex128 = defType("complex128")
 	defType("float32")
diff --git a/libgo/go/exp/winfsnotify/winfsnotify_test.go b/libgo/go/exp/winfsnotify/winfsnotify_test.go
index 6e264d0..fb2b825 100644
--- a/libgo/go/exp/winfsnotify/winfsnotify_test.go
+++ b/libgo/go/exp/winfsnotify/winfsnotify_test.go
@@ -40,7 +40,7 @@ func TestNotifyEvents(t *testing.T) {
 	// Add a watch for testDir
 	os.RemoveAll(testDir)
 	if err = os.Mkdir(testDir, 0777); err != nil {
-		t.Fatalf("Failed to create test directory", err)
+		t.Fatalf("Failed to create test directory: %s", err)
 	}
 	defer os.RemoveAll(testDir)
 	err = watcher.AddWatch(testDir, mask)
diff --git a/libgo/go/expvar/expvar.go b/libgo/go/expvar/expvar.go
index 7b733fa..f5d6ed5 100644
--- a/libgo/go/expvar/expvar.go
+++ b/libgo/go/expvar/expvar.go
@@ -102,7 +102,7 @@ func (v *Map) String() string {
 		if !first {
 			fmt.Fprintf(b, ", ")
 		}
-		fmt.Fprintf(b, "\"%s\": %v", key, val.String())
+		fmt.Fprintf(b, "\"%s\": %v", key, val)
 		first = false
 	}
 	fmt.Fprintf(b, "}")
diff --git a/libgo/go/fmt/doc.go b/libgo/go/fmt/doc.go
index c993e57..6713f0a1 100644
--- a/libgo/go/fmt/doc.go
+++ b/libgo/go/fmt/doc.go
@@ -89,10 +89,14 @@
 	If an operand implements interface Formatter, that interface
 	can be used for fine control of formatting.
 
-	If an operand implements method String() string that method
+	Next, if an operand implements the error interface, the Error method
 	will be used to convert the object to a string, which will then
-	be formatted as required by the verb (if any). To avoid
-	recursion in cases such as
+	be formatted as required by the verb (if any).
+
+	Finally, if an operand implements method String() string that method
+	will be used to convert the object to a string, which will then
+	be formatted as required by the verb (if any).
+	To avoid recursion in cases such as
 		type X int
 		func (x X) String() string { return Sprintf("%d", x) }
 	cast the value before recurring:
diff --git a/libgo/go/fmt/fmt_test.go b/libgo/go/fmt/fmt_test.go
index 38280d6..db83f85 100644
--- a/libgo/go/fmt/fmt_test.go
+++ b/libgo/go/fmt/fmt_test.go
@@ -73,7 +73,7 @@ type C struct {
 
 type F int
 
-func (f F) Format(s State, c int) {
+func (f F) Format(s State, c rune) {
 	Fprintf(s, "<%c=F(%d)>", c, int(f))
 }
 
@@ -356,7 +356,7 @@ var fmttests = []struct {
 	{"%#v", map[string]int{"a": 1}, `map[string] int{"a":1}`},
 	{"%#v", map[string]B{"a": {1, 2}}, `map[string] fmt_test.B{"a":fmt_test.B{I:1, j:2}}`},
 	{"%#v", []string{"a", "b"}, `[]string{"a", "b"}`},
-	{"%#v", SI{}, `fmt_test.SI{I:interface { }(nil)}`},
+	{"%#v", SI{}, `fmt_test.SI{I:interface {}(nil)}`},
 
 	// slices with other formats
 	{"%#x", []int{1, 2, 15}, `[0x1 0x2 0xf]`},
@@ -546,7 +546,7 @@ func TestCountMallocs(t *testing.T) {
 
 type flagPrinter struct{}
 
-func (*flagPrinter) Format(f State, c int) {
+func (*flagPrinter) Format(f State, c rune) {
 	s := "%"
 	for i := 0; i < 128; i++ {
 		if f.Flag(i) {
@@ -746,7 +746,7 @@ type PanicF struct {
 }
 
 // Value receiver.
-func (p PanicF) Format(f State, c int) {
+func (p PanicF) Format(f State, c rune) {
 	panic(p.message)
 }
 
diff --git a/libgo/go/fmt/format.go b/libgo/go/fmt/format.go
index 24b15a2..80eb986 100644
--- a/libgo/go/fmt/format.go
+++ b/libgo/go/fmt/format.go
@@ -242,8 +242,8 @@ func (f *fmt) integer(a int64, base uint64, signedness bool, digits string) {
 	}
 
 	// If we want a quoted char for %#U, move the data up to make room.
-	if f.unicode && f.uniQuote && a >= 0 && a <= unicode.MaxRune && unicode.IsPrint(int(a)) {
-		runeWidth := utf8.RuneLen(int(a))
+	if f.unicode && f.uniQuote && a >= 0 && a <= unicode.MaxRune && unicode.IsPrint(rune(a)) {
+		runeWidth := utf8.RuneLen(rune(a))
 		width := 1 + 1 + runeWidth + 1 // space, quote, rune, quote
 		copy(buf[i-width:], buf[i:])   // guaranteed to have enough room.
 		i -= width
@@ -253,7 +253,7 @@ func (f *fmt) integer(a int64, base uint64, signedness bool, digits string) {
 		j++
 		buf[j] = '\''
 		j++
-		utf8.EncodeRune(buf[j:], int(a))
+		utf8.EncodeRune(buf[j:], rune(a))
 		j += runeWidth
 		buf[j] = '\''
 	}
@@ -400,7 +400,7 @@ func (f *fmt) fmt_G32(v float32) { f.plusSpace(strconv.Ftoa32(v, 'G', doPrec(f,
 func (f *fmt) fmt_fb32(v float32) { f.padString(strconv.Ftoa32(v, 'b', 0)) }
 
 // fmt_c64 formats a complex64 according to the verb.
-func (f *fmt) fmt_c64(v complex64, verb int) {
+func (f *fmt) fmt_c64(v complex64, verb rune) {
 	f.buf.WriteByte('(')
 	r := real(v)
 	for i := 0; ; i++ {
@@ -426,7 +426,7 @@ func (f *fmt) fmt_c64(v complex64, verb int) {
 }
 
 // fmt_c128 formats a complex128 according to the verb.
-func (f *fmt) fmt_c128(v complex128, verb int) {
+func (f *fmt) fmt_c128(v complex128, verb rune) {
 	f.buf.WriteByte('(')
 	r := real(v)
 	for i := 0; ; i++ {
diff --git a/libgo/go/fmt/print.go b/libgo/go/fmt/print.go
index 710baee..5e0237f 100644
--- a/libgo/go/fmt/print.go
+++ b/libgo/go/fmt/print.go
@@ -51,7 +51,7 @@ type State interface {
 // The implementation of Format may call Sprintf or Fprintf(f) etc.
 // to generate its output.
 type Formatter interface {
-	Format(f State, c int)
+	Format(f State, c rune)
 }
 
 // Stringer is implemented by any value that has a String method,
@@ -159,7 +159,7 @@ func (p *pp) Flag(b int) bool {
 	return false
 }
 
-func (p *pp) add(c int) {
+func (p *pp) add(c rune) {
 	p.buf.WriteRune(c)
 }
 
@@ -297,7 +297,7 @@ func (p *pp) unknownType(v interface{}) {
 	p.buf.WriteByte('?')
 }
 
-func (p *pp) badVerb(verb int) {
+func (p *pp) badVerb(verb rune) {
 	p.add('%')
 	p.add('!')
 	p.add(verb)
@@ -317,7 +317,7 @@ func (p *pp) badVerb(verb int) {
 	p.add(')')
 }
 
-func (p *pp) fmtBool(v bool, verb int) {
+func (p *pp) fmtBool(v bool, verb rune) {
 	switch verb {
 	case 't', 'v':
 		p.fmt.fmt_boolean(v)
@@ -328,15 +328,15 @@ func (p *pp) fmtBool(v bool, verb int) {
 
 // fmtC formats a rune for the 'c' format.
 func (p *pp) fmtC(c int64) {
-	rune := int(c) // Check for overflow.
-	if int64(rune) != c {
-		rune = utf8.RuneError
+	r := rune(c) // Check for overflow.
+	if int64(r) != c {
+		r = utf8.RuneError
 	}
-	w := utf8.EncodeRune(p.runeBuf[0:utf8.UTFMax], rune)
+	w := utf8.EncodeRune(p.runeBuf[0:utf8.UTFMax], r)
 	p.fmt.pad(p.runeBuf[0:w])
 }
 
-func (p *pp) fmtInt64(v int64, verb int) {
+func (p *pp) fmtInt64(v int64, verb rune) {
 	switch verb {
 	case 'b':
 		p.fmt.integer(v, 2, signed, ldigits)
@@ -394,7 +394,7 @@ func (p *pp) fmtUnicode(v int64) {
 	p.fmt.sharp = sharp
 }
 
-func (p *pp) fmtUint64(v uint64, verb int, goSyntax bool) {
+func (p *pp) fmtUint64(v uint64, verb rune, goSyntax bool) {
 	switch verb {
 	case 'b':
 		p.fmt.integer(int64(v), 2, unsigned, ldigits)
@@ -427,7 +427,7 @@ func (p *pp) fmtUint64(v uint64, verb int, goSyntax bool) {
 	}
 }
 
-func (p *pp) fmtFloat32(v float32, verb int) {
+func (p *pp) fmtFloat32(v float32, verb rune) {
 	switch verb {
 	case 'b':
 		p.fmt.fmt_fb32(v)
@@ -446,7 +446,7 @@ func (p *pp) fmtFloat32(v float32, verb int) {
 	}
 }
 
-func (p *pp) fmtFloat64(v float64, verb int) {
+func (p *pp) fmtFloat64(v float64, verb rune) {
 	switch verb {
 	case 'b':
 		p.fmt.fmt_fb64(v)
@@ -465,7 +465,7 @@ func (p *pp) fmtFloat64(v float64, verb int) {
 	}
 }
 
-func (p *pp) fmtComplex64(v complex64, verb int) {
+func (p *pp) fmtComplex64(v complex64, verb rune) {
 	switch verb {
 	case 'e', 'E', 'f', 'F', 'g', 'G':
 		p.fmt.fmt_c64(v, verb)
@@ -476,7 +476,7 @@ func (p *pp) fmtComplex64(v complex64, verb int) {
 	}
 }
 
-func (p *pp) fmtComplex128(v complex128, verb int) {
+func (p *pp) fmtComplex128(v complex128, verb rune) {
 	switch verb {
 	case 'e', 'E', 'f', 'F', 'g', 'G':
 		p.fmt.fmt_c128(v, verb)
@@ -487,7 +487,7 @@ func (p *pp) fmtComplex128(v complex128, verb int) {
 	}
 }
 
-func (p *pp) fmtString(v string, verb int, goSyntax bool) {
+func (p *pp) fmtString(v string, verb rune, goSyntax bool) {
 	switch verb {
 	case 'v':
 		if goSyntax {
@@ -508,7 +508,7 @@ func (p *pp) fmtString(v string, verb int, goSyntax bool) {
 	}
 }
 
-func (p *pp) fmtBytes(v []byte, verb int, goSyntax bool, depth int) {
+func (p *pp) fmtBytes(v []byte, verb rune, goSyntax bool, depth int) {
 	if verb == 'v' || verb == 'd' {
 		if goSyntax {
 			p.buf.Write(bytesBytes)
@@ -547,7 +547,7 @@ func (p *pp) fmtBytes(v []byte, verb int, goSyntax bool, depth int) {
 	}
 }
 
-func (p *pp) fmtPointer(value reflect.Value, verb int, goSyntax bool) {
+func (p *pp) fmtPointer(value reflect.Value, verb rune, goSyntax bool) {
 	var u uintptr
 	switch value.Kind() {
 	case reflect.Chan, reflect.Func, reflect.Map, reflect.Ptr, reflect.Slice, reflect.UnsafePointer:
@@ -579,7 +579,7 @@ var (
 	uintptrBits = reflect.TypeOf(uintptr(0)).Bits()
 )
 
-func (p *pp) catchPanic(field interface{}, verb int) {
+func (p *pp) catchPanic(field interface{}, verb rune) {
 	if err := recover(); err != nil {
 		// If it's a nil pointer, just say "<nil>". The likeliest causes are a
 		// Stringer that fails to guard against nil or a nil pointer for a
@@ -604,7 +604,7 @@ func (p *pp) catchPanic(field interface{}, verb int) {
 	}
 }
 
-func (p *pp) handleMethods(verb int, plus, goSyntax bool, depth int) (wasString, handled bool) {
+func (p *pp) handleMethods(verb rune, plus, goSyntax bool, depth int) (wasString, handled bool) {
 	// Is it a Formatter?
 	if formatter, ok := p.field.(Formatter); ok {
 		handled = true
@@ -630,12 +630,23 @@ func (p *pp) handleMethods(verb int, plus, goSyntax bool, depth int) (wasString,
 			return
 		}
 	} else {
-		// Is it a Stringer?
-		if stringer, ok := p.field.(Stringer); ok {
+		// Is it an error or Stringer?
+		// The duplication in the bodies is necessary:
+		// setting wasString and handled and deferring catchPanic
+		// must happen before calling the method.
+		switch v := p.field.(type) {
+		case os.Error:
 			wasString = false
 			handled = true
 			defer p.catchPanic(p.field, verb)
-			p.printField(stringer.String(), verb, plus, false, depth)
+			p.printField(v.String(), verb, plus, false, depth)
+			return
+
+		case Stringer:
+			wasString = false
+			handled = true
+			defer p.catchPanic(p.field, verb)
+			p.printField(v.String(), verb, plus, false, depth)
 			return
 		}
 	}
@@ -643,7 +654,7 @@ func (p *pp) handleMethods(verb int, plus, goSyntax bool, depth int) (wasString,
 	return
 }
 
-func (p *pp) printField(field interface{}, verb int, plus, goSyntax bool, depth int) (wasString bool) {
+func (p *pp) printField(field interface{}, verb rune, plus, goSyntax bool, depth int) (wasString bool) {
 	if field == nil {
 		if verb == 'T' || verb == 'v' {
 			p.buf.Write(nilAngleBytes)
@@ -719,7 +730,7 @@ func (p *pp) printField(field interface{}, verb int, plus, goSyntax bool, depth
 }
 
 // printValue is like printField but starts with a reflect value, not an interface{} value.
-func (p *pp) printValue(value reflect.Value, verb int, plus, goSyntax bool, depth int) (wasString bool) {
+func (p *pp) printValue(value reflect.Value, verb rune, plus, goSyntax bool, depth int) (wasString bool) {
 	if !value.IsValid() {
 		if verb == 'T' || verb == 'v' {
 			p.buf.Write(nilAngleBytes)
@@ -755,7 +766,7 @@ func (p *pp) printValue(value reflect.Value, verb int, plus, goSyntax bool, dept
 
 // printReflectValue is the fallback for both printField and printValue.
 // It uses reflect to print the value.
-func (p *pp) printReflectValue(value reflect.Value, verb int, plus, goSyntax bool, depth int) (wasString bool) {
+func (p *pp) printReflectValue(value reflect.Value, verb rune, plus, goSyntax bool, depth int) (wasString bool) {
 	oldValue := p.value
 	p.value = value
 BigSwitch:
diff --git a/libgo/go/fmt/scan.go b/libgo/go/fmt/scan.go
index 259451d..eae952c 100644
--- a/libgo/go/fmt/scan.go
+++ b/libgo/go/fmt/scan.go
@@ -32,7 +32,7 @@ type ScanState interface {
 	// If invoked during Scanln, Fscanln, or Sscanln, ReadRune() will
 	// return EOF after returning the first '\n' or when reading beyond
 	// the specified width.
-	ReadRune() (rune int, size int, err os.Error)
+	ReadRune() (r rune, size int, err os.Error)
 	// UnreadRune causes the next call to ReadRune to return the same rune.
 	UnreadRune() os.Error
 	// SkipSpace skips space in the input. Newlines are treated as space 
@@ -47,7 +47,7 @@ type ScanState interface {
 	// EOF.  The returned slice points to shared data that may be overwritten
 	// by the next call to Token, a call to a Scan function using the ScanState
 	// as input, or when the calling Scan method returns.
-	Token(skipSpace bool, f func(int) bool) (token []byte, err os.Error)
+	Token(skipSpace bool, f func(rune) bool) (token []byte, err os.Error)
 	// Width returns the value of the width option and whether it has been set.
 	// The unit is Unicode code points.
 	Width() (wid int, ok bool)
@@ -62,7 +62,7 @@ type ScanState interface {
 // receiver, which must be a pointer to be useful.  The Scan method is called
 // for any argument to Scan, Scanf, or Scanln that implements it.
 type Scanner interface {
-	Scan(state ScanState, verb int) os.Error
+	Scan(state ScanState, verb rune) os.Error
 }
 
 // Scan scans text read from standard input, storing successive
@@ -149,8 +149,8 @@ const eof = -1
 type ss struct {
 	rr       io.RuneReader // where to read input
 	buf      bytes.Buffer  // token accumulator
-	peekRune int           // one-rune lookahead
-	prevRune int           // last rune returned by ReadRune
+	peekRune rune          // one-rune lookahead
+	prevRune rune          // last rune returned by ReadRune
 	count    int           // runes consumed so far.
 	atEOF    bool          // already read EOF
 	ssave
@@ -174,12 +174,12 @@ func (s *ss) Read(buf []byte) (n int, err os.Error) {
 	return 0, os.NewError("ScanState's Read should not be called. Use ReadRune")
 }
 
-func (s *ss) ReadRune() (rune int, size int, err os.Error) {
+func (s *ss) ReadRune() (r rune, size int, err os.Error) {
 	if s.peekRune >= 0 {
 		s.count++
-		rune = s.peekRune
-		size = utf8.RuneLen(rune)
-		s.prevRune = rune
+		r = s.peekRune
+		size = utf8.RuneLen(r)
+		s.prevRune = r
 		s.peekRune = -1
 		return
 	}
@@ -188,10 +188,10 @@ func (s *ss) ReadRune() (rune int, size int, err os.Error) {
 		return
 	}
 
-	rune, size, err = s.rr.ReadRune()
+	r, size, err = s.rr.ReadRune()
 	if err == nil {
 		s.count++
-		s.prevRune = rune
+		s.prevRune = r
 	} else if err == os.EOF {
 		s.atEOF = true
 	}
@@ -207,8 +207,8 @@ func (s *ss) Width() (wid int, ok bool) {
 
 // The public method returns an error; this private one panics.
 // If getRune reaches EOF, the return value is EOF (-1).
-func (s *ss) getRune() (rune int) {
-	rune, _, err := s.ReadRune()
+func (s *ss) getRune() (r rune) {
+	r, _, err := s.ReadRune()
 	if err != nil {
 		if err == os.EOF {
 			return eof
@@ -221,9 +221,9 @@ func (s *ss) getRune() (rune int) {
 // mustReadRune turns os.EOF into a panic(io.ErrUnexpectedEOF).
 // It is called in cases such as string scanning where an EOF is a
 // syntax error.
-func (s *ss) mustReadRune() (rune int) {
-	rune = s.getRune()
-	if rune == eof {
+func (s *ss) mustReadRune() (r rune) {
+	r = s.getRune()
+	if r == eof {
 		s.error(io.ErrUnexpectedEOF)
 	}
 	return
@@ -248,7 +248,7 @@ func (s *ss) errorString(err string) {
 	panic(scanError{os.NewError(err)})
 }
 
-func (s *ss) Token(skipSpace bool, f func(int) bool) (tok []byte, err os.Error) {
+func (s *ss) Token(skipSpace bool, f func(rune) bool) (tok []byte, err os.Error) {
 	defer func() {
 		if e := recover(); e != nil {
 			if se, ok := e.(scanError); ok {
@@ -267,7 +267,7 @@ func (s *ss) Token(skipSpace bool, f func(int) bool) (tok []byte, err os.Error)
 }
 
 // notSpace is the default scanning function used in Token.
-func notSpace(r int) bool {
+func notSpace(r rune) bool {
 	return !unicode.IsSpace(r)
 }
 
@@ -308,13 +308,13 @@ func (r *readRune) unread(buf []byte) {
 
 // ReadRune returns the next UTF-8 encoded code point from the
 // io.Reader inside r.
-func (r *readRune) ReadRune() (rune int, size int, err os.Error) {
+func (r *readRune) ReadRune() (rr rune, size int, err os.Error) {
 	r.buf[0], err = r.readByte()
 	if err != nil {
 		return 0, 0, err
 	}
 	if r.buf[0] < utf8.RuneSelf { // fast check for common ASCII case
-		rune = int(r.buf[0])
+		rr = rune(r.buf[0])
 		return
 	}
 	var n int
@@ -328,7 +328,7 @@ func (r *readRune) ReadRune() (rune int, size int, err os.Error) {
 			return
 		}
 	}
-	rune, size = utf8.DecodeRune(r.buf[0:n])
+	rr, size = utf8.DecodeRune(r.buf[0:n])
 	if size < n { // an error
 		r.unread(r.buf[size:n])
 	}
@@ -387,11 +387,11 @@ func (s *ss) free(old ssave) {
 // skipSpace skips spaces and maybe newlines.
 func (s *ss) skipSpace(stopAtNewline bool) {
 	for {
-		rune := s.getRune()
-		if rune == eof {
+		r := s.getRune()
+		if r == eof {
 			return
 		}
-		if rune == '\n' {
+		if r == '\n' {
 			if stopAtNewline {
 				break
 			}
@@ -401,7 +401,7 @@ func (s *ss) skipSpace(stopAtNewline bool) {
 			s.errorString("unexpected newline")
 			return
 		}
-		if !unicode.IsSpace(rune) {
+		if !unicode.IsSpace(r) {
 			s.UnreadRune()
 			break
 		}
@@ -411,21 +411,21 @@ func (s *ss) skipSpace(stopAtNewline bool) {
 // token returns the next space-delimited string from the input.  It
 // skips white space.  For Scanln, it stops at newlines.  For Scan,
 // newlines are treated as spaces.
-func (s *ss) token(skipSpace bool, f func(int) bool) []byte {
+func (s *ss) token(skipSpace bool, f func(rune) bool) []byte {
 	if skipSpace {
 		s.skipSpace(false)
 	}
 	// read until white space or newline
 	for {
-		rune := s.getRune()
-		if rune == eof {
+		r := s.getRune()
+		if r == eof {
 			break
 		}
-		if !f(rune) {
+		if !f(r) {
 			s.UnreadRune()
 			break
 		}
-		s.buf.WriteRune(rune)
+		s.buf.WriteRune(r)
 	}
 	return s.buf.Bytes()
 }
@@ -441,17 +441,17 @@ var boolError = os.NewError("syntax error scanning boolean")
 // consume reads the next rune in the input and reports whether it is in the ok string.
 // If accept is true, it puts the character into the input token.
 func (s *ss) consume(ok string, accept bool) bool {
-	rune := s.getRune()
-	if rune == eof {
+	r := s.getRune()
+	if r == eof {
 		return false
 	}
-	if strings.IndexRune(ok, rune) >= 0 {
+	if strings.IndexRune(ok, r) >= 0 {
 		if accept {
-			s.buf.WriteRune(rune)
+			s.buf.WriteRune(r)
 		}
 		return true
 	}
-	if rune != eof && accept {
+	if r != eof && accept {
 		s.UnreadRune()
 	}
 	return false
@@ -459,16 +459,16 @@ func (s *ss) consume(ok string, accept bool) bool {
 
 // peek reports whether the next character is in the ok string, without consuming it.
 func (s *ss) peek(ok string) bool {
-	rune := s.getRune()
-	if rune != eof {
+	r := s.getRune()
+	if r != eof {
 		s.UnreadRune()
 	}
-	return strings.IndexRune(ok, rune) >= 0
+	return strings.IndexRune(ok, r) >= 0
 }
 
 func (s *ss) notEOF() {
 	// Guarantee there is data to be read.
-	if rune := s.getRune(); rune == eof {
+	if r := s.getRune(); r == eof {
 		panic(os.EOF)
 	}
 	s.UnreadRune()
@@ -481,7 +481,7 @@ func (s *ss) accept(ok string) bool {
 }
 
 // okVerb verifies that the verb is present in the list, setting s.err appropriately if not.
-func (s *ss) okVerb(verb int, okVerbs, typ string) bool {
+func (s *ss) okVerb(verb rune, okVerbs, typ string) bool {
 	for _, v := range okVerbs {
 		if v == verb {
 			return true
@@ -492,7 +492,7 @@ func (s *ss) okVerb(verb int, okVerbs, typ string) bool {
 }
 
 // scanBool returns the value of the boolean represented by the next token.
-func (s *ss) scanBool(verb int) bool {
+func (s *ss) scanBool(verb rune) bool {
 	s.skipSpace(false)
 	s.notEOF()
 	if !s.okVerb(verb, "tv", "boolean") {
@@ -530,7 +530,7 @@ const (
 )
 
 // getBase returns the numeric base represented by the verb and its digit string.
-func (s *ss) getBase(verb int) (base int, digits string) {
+func (s *ss) getBase(verb rune) (base int, digits string) {
 	s.okVerb(verb, "bdoUxXv", "integer") // sets s.err
 	base = 10
 	digits = decimalDigits
@@ -564,13 +564,13 @@ func (s *ss) scanNumber(digits string, haveDigits bool) string {
 // scanRune returns the next rune value in the input.
 func (s *ss) scanRune(bitSize int) int64 {
 	s.notEOF()
-	rune := int64(s.getRune())
+	r := int64(s.getRune())
 	n := uint(bitSize)
-	x := (rune << (64 - n)) >> (64 - n)
-	if x != rune {
-		s.errorString("overflow on character value " + string(rune))
+	x := (r << (64 - n)) >> (64 - n)
+	if x != r {
+		s.errorString("overflow on character value " + string(r))
 	}
-	return rune
+	return r
 }
 
 // scanBasePrefix reports whether the integer begins with a 0 or 0x,
@@ -593,7 +593,7 @@ func (s *ss) scanBasePrefix() (base int, digits string, found bool) {
 
 // scanInt returns the value of the integer represented by the next
 // token, checking for overflow.  Any error is stored in s.err.
-func (s *ss) scanInt(verb int, bitSize int) int64 {
+func (s *ss) scanInt(verb rune, bitSize int) int64 {
 	if verb == 'c' {
 		return s.scanRune(bitSize)
 	}
@@ -626,7 +626,7 @@ func (s *ss) scanInt(verb int, bitSize int) int64 {
 
 // scanUint returns the value of the unsigned integer represented
 // by the next token, checking for overflow.  Any error is stored in s.err.
-func (s *ss) scanUint(verb int, bitSize int) uint64 {
+func (s *ss) scanUint(verb rune, bitSize int) uint64 {
 	if verb == 'c' {
 		return uint64(s.scanRune(bitSize))
 	}
@@ -747,7 +747,7 @@ func (s *ss) convertFloat(str string, n int) float64 {
 // The atof argument is a type-specific reader for the underlying type.
 // If we're reading complex64, atof will parse float32s and convert them
 // to float64's to avoid reproducing this code for each complex type.
-func (s *ss) scanComplex(verb int, n int) complex128 {
+func (s *ss) scanComplex(verb rune, n int) complex128 {
 	if !s.okVerb(verb, floatVerbs, "complex") {
 		return 0
 	}
@@ -761,7 +761,7 @@ func (s *ss) scanComplex(verb int, n int) complex128 {
 
 // convertString returns the string represented by the next input characters.
 // The format of the input is determined by the verb.
-func (s *ss) convertString(verb int) (str string) {
+func (s *ss) convertString(verb rune) (str string) {
 	if !s.okVerb(verb, "svqx", "string") {
 		return ""
 	}
@@ -786,26 +786,26 @@ func (s *ss) quotedString() string {
 	case '`':
 		// Back-quoted: Anything goes until EOF or back quote.
 		for {
-			rune := s.mustReadRune()
-			if rune == quote {
+			r := s.mustReadRune()
+			if r == quote {
 				break
 			}
-			s.buf.WriteRune(rune)
+			s.buf.WriteRune(r)
 		}
 		return s.buf.String()
 	case '"':
 		// Double-quoted: Include the quotes and let strconv.Unquote do the backslash escapes.
 		s.buf.WriteRune(quote)
 		for {
-			rune := s.mustReadRune()
-			s.buf.WriteRune(rune)
-			if rune == '\\' {
+			r := s.mustReadRune()
+			s.buf.WriteRune(r)
+			if r == '\\' {
 				// In a legal backslash escape, no matter how long, only the character
 				// immediately after the escape can itself be a backslash or quote.
 				// Thus we only need to protect the first character after the backslash.
-				rune := s.mustReadRune()
-				s.buf.WriteRune(rune)
-			} else if rune == '"' {
+				r := s.mustReadRune()
+				s.buf.WriteRune(r)
+			} else if r == '"' {
 				break
 			}
 		}
@@ -821,7 +821,8 @@ func (s *ss) quotedString() string {
 }
 
 // hexDigit returns the value of the hexadecimal digit
-func (s *ss) hexDigit(digit int) int {
+func (s *ss) hexDigit(d rune) int {
+	digit := int(d)
 	switch digit {
 	case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
 		return digit - '0'
@@ -871,7 +872,7 @@ const floatVerbs = "beEfFgGv"
 const hugeWid = 1 << 30
 
 // scanOne scans a single value, deriving the scanner from the type of the argument.
-func (s *ss) scanOne(verb int, field interface{}) {
+func (s *ss) scanOne(verb rune, field interface{}) {
 	s.buf.Reset()
 	var err os.Error
 	// If the parameter has its own Scan method, use that.
@@ -997,11 +998,11 @@ func (s *ss) doScan(a []interface{}) (numProcessed int, err os.Error) {
 	// Check for newline if required.
 	if !s.nlIsSpace {
 		for {
-			rune := s.getRune()
-			if rune == '\n' || rune == eof {
+			r := s.getRune()
+			if r == '\n' || r == eof {
 				break
 			}
-			if !unicode.IsSpace(rune) {
+			if !unicode.IsSpace(r) {
 				s.errorString("Scan: expected newline")
 				break
 			}
diff --git a/libgo/go/fmt/scan_test.go b/libgo/go/fmt/scan_test.go
index 3f06e57..fbc28c1 100644
--- a/libgo/go/fmt/scan_test.go
+++ b/libgo/go/fmt/scan_test.go
@@ -87,8 +87,8 @@ type FloatTest struct {
 // Xs accepts any non-empty run of the verb character
 type Xs string
 
-func (x *Xs) Scan(state ScanState, verb int) os.Error {
-	tok, err := state.Token(true, func(r int) bool { return r == verb })
+func (x *Xs) Scan(state ScanState, verb rune) os.Error {
+	tok, err := state.Token(true, func(r rune) bool { return r == verb })
 	if err != nil {
 		return err
 	}
@@ -109,7 +109,7 @@ type IntString struct {
 	s string
 }
 
-func (s *IntString) Scan(state ScanState, verb int) os.Error {
+func (s *IntString) Scan(state ScanState, verb rune) os.Error {
 	if _, err := Fscan(state, &s.i); err != nil {
 		return err
 	}
@@ -749,8 +749,8 @@ type TwoLines string
 
 // Attempt to read two lines into the object.  Scanln should prevent this
 // because it stops at newline; Scan and Scanf should be fine.
-func (t *TwoLines) Scan(state ScanState, verb int) os.Error {
-	chars := make([]int, 0, 100)
+func (t *TwoLines) Scan(state ScanState, verb rune) os.Error {
+	chars := make([]rune, 0, 100)
 	for nlCount := 0; nlCount < 2; {
 		c, _, err := state.ReadRune()
 		if err != nil {
@@ -812,7 +812,7 @@ type RecursiveInt struct {
 	next *RecursiveInt
 }
 
-func (r *RecursiveInt) Scan(state ScanState, verb int) (err os.Error) {
+func (r *RecursiveInt) Scan(state ScanState, verb rune) (err os.Error) {
 	_, err = Fscan(state, &r.i)
 	if err != nil {
 		return
@@ -838,8 +838,7 @@ func scanInts(r *RecursiveInt, b *bytes.Buffer) (err os.Error) {
 	if err != nil {
 		return
 	}
-	var c int
-	c, _, err = b.ReadRune()
+	c, _, err := b.ReadRune()
 	if err != nil {
 		if err == os.EOF {
 			err = nil
diff --git a/libgo/go/go/ast/ast.go b/libgo/go/go/ast/ast.go
index 22bd5ee..f8caafc 100644
--- a/libgo/go/go/ast/ast.go
+++ b/libgo/go/go/ast/ast.go
@@ -752,6 +752,7 @@ type (
 		Name    *Ident        // local package name (including "."); or nil
 		Path    *BasicLit     // import path
 		Comment *CommentGroup // line comments; or nil
+		EndPos  token.Pos     // end of spec (overrides Path.Pos if nonzero)
 	}
 
 	// A ValueSpec node represents a constant or variable declaration
@@ -785,7 +786,13 @@ func (s *ImportSpec) Pos() token.Pos {
 func (s *ValueSpec) Pos() token.Pos { return s.Names[0].Pos() }
 func (s *TypeSpec) Pos() token.Pos  { return s.Name.Pos() }
 
-func (s *ImportSpec) End() token.Pos { return s.Path.End() }
+func (s *ImportSpec) End() token.Pos {
+	if s.EndPos != 0 {
+		return s.EndPos
+	}
+	return s.Path.End()
+}
+
 func (s *ValueSpec) End() token.Pos {
 	if n := len(s.Values); n > 0 {
 		return s.Values[n-1].End()
diff --git a/libgo/go/go/ast/print.go b/libgo/go/go/ast/print.go
index 62a3048..e36f99f 100644
--- a/libgo/go/go/ast/print.go
+++ b/libgo/go/go/ast/print.go
@@ -149,7 +149,7 @@ func (p *printer) print(x reflect.Value) {
 		p.print(x.Elem())
 
 	case reflect.Map:
-		p.printf("%s (len = %d) {\n", x.Type().String(), x.Len())
+		p.printf("%s (len = %d) {\n", x.Type(), x.Len())
 		p.indent++
 		for _, key := range x.MapKeys() {
 			p.print(key)
@@ -178,7 +178,7 @@ func (p *printer) print(x reflect.Value) {
 			p.printf("%#q", s)
 			return
 		}
-		p.printf("%s (len = %d) {\n", x.Type().String(), x.Len())
+		p.printf("%s (len = %d) {\n", x.Type(), x.Len())
 		p.indent++
 		for i, n := 0, x.Len(); i < n; i++ {
 			p.printf("%d: ", i)
@@ -189,7 +189,7 @@ func (p *printer) print(x reflect.Value) {
 		p.printf("}")
 
 	case reflect.Struct:
-		p.printf("%s {\n", x.Type().String())
+		p.printf("%s {\n", x.Type())
 		p.indent++
 		t := x.Type()
 		for i, n := 0, t.NumField(); i < n; i++ {
diff --git a/libgo/go/go/build/build_test.go b/libgo/go/go/build/build_test.go
index 68a4180..398e31c 100644
--- a/libgo/go/go/build/build_test.go
+++ b/libgo/go/go/build/build_test.go
@@ -28,7 +28,7 @@ var buildPkgs = []struct {
 			GoFiles:      []string{"pkgtest.go"},
 			SFiles:       []string{"sqrt_" + runtime.GOARCH + ".s"},
 			Package:      "pkgtest",
-			Imports:      []string{"os"},
+			Imports:      []string{"bytes"},
 			TestImports:  []string{"fmt", "pkgtest"},
 			TestGoFiles:  sortstr([]string{"sqrt_test.go", "sqrt_" + runtime.GOARCH + "_test.go"}),
 			XTestGoFiles: []string{"xsqrt_test.go"},
diff --git a/libgo/go/go/build/dir.go b/libgo/go/go/build/dir.go
index 3ee10ab..b67f999 100644
--- a/libgo/go/go/build/dir.go
+++ b/libgo/go/go/build/dir.go
@@ -461,10 +461,10 @@ func safeName(s string) bool {
 //
 func splitQuoted(s string) (r []string, err os.Error) {
 	var args []string
-	arg := make([]int, len(s))
+	arg := make([]rune, len(s))
 	escaped := false
 	quoted := false
-	quote := 0
+	quote := rune(0)
 	i := 0
 	for _, rune := range s {
 		switch {
diff --git a/libgo/go/go/build/pkgtest/pkgtest.go b/libgo/go/go/build/pkgtest/pkgtest.go
index 03ebb98..08eea1e 100644
--- a/libgo/go/go/build/pkgtest/pkgtest.go
+++ b/libgo/go/go/build/pkgtest/pkgtest.go
@@ -4,9 +4,9 @@
 
 package pkgtest
 
-import "os"
+import "bytes"
 
-func Foo() os.Error {
+func Foo() *bytes.Buffer {
 	return nil
 }
 
diff --git a/libgo/go/go/doc/doc.go b/libgo/go/go/doc/doc.go
index c7fed97..9174864 100644
--- a/libgo/go/go/doc/doc.go
+++ b/libgo/go/go/doc/doc.go
@@ -175,8 +175,6 @@ func setFunc(table map[string]*ast.FuncDecl, f *ast.FuncDecl) {
 }
 
 func (doc *docReader) addFunc(fun *ast.FuncDecl) {
-	name := fun.Name.Name
-
 	// determine if it should be associated with a type
 	if fun.Recv != nil {
 		// method
@@ -205,19 +203,6 @@ func (doc *docReader) addFunc(fun *ast.FuncDecl) {
 			typ := doc.lookupTypeDoc(tname)
 			if typ != nil {
 				// named and exported result type
-
-				// Work-around for failure of heuristic: In package os
-				// too many functions are considered factory functions
-				// for the Error type. Eliminate manually for now as
-				// this appears to be the only important case in the
-				// current library where the heuristic fails.
-				if doc.pkgName == "os" && tname == "Error" &&
-					name != "NewError" && name != "NewSyscallError" {
-					// not a factory function for os.Error
-					setFunc(doc.funcs, fun) // treat as ordinary function
-					return
-				}
-
 				setFunc(typ.factories, fun)
 				return
 			}
diff --git a/libgo/go/go/parser/parser.go b/libgo/go/go/parser/parser.go
index be82b2f..e2c9441 100644
--- a/libgo/go/go/parser/parser.go
+++ b/libgo/go/go/parser/parser.go
@@ -434,7 +434,9 @@ func (p *parser) parseLhsList() []ast.Expr {
 	switch p.tok {
 	case token.DEFINE:
 		// lhs of a short variable declaration
-		p.shortVarDecl(p.makeIdentList(list))
+		// but doesn't enter scope until later:
+		// caller must call p.shortVarDecl(p.makeIdentList(list))
+		// at appropriate time.
 	case token.COLON:
 		// lhs of a label declaration or a communication clause of a select
 		// statement (parseLhsList is not called when parsing the case clause
@@ -1398,6 +1400,9 @@ func (p *parser) parseSimpleStmt(mode int) (ast.Stmt, bool) {
 		} else {
 			y = p.parseRhsList()
 		}
+		if tok == token.DEFINE {
+			p.shortVarDecl(p.makeIdentList(x))
+		}
 		return &ast.AssignStmt{x, pos, tok, y}, isRange
 	}
 
@@ -1722,6 +1727,9 @@ func (p *parser) parseCommClause() *ast.CommClause {
 				}
 				p.next()
 				rhs = p.parseRhs()
+				if tok == token.DEFINE && lhs != nil {
+					p.shortVarDecl(p.makeIdentList(lhs))
+				}
 			} else {
 				// rhs must be single receive operation
 				if len(lhs) > 1 {
@@ -1909,7 +1917,7 @@ func parseImportSpec(p *parser, doc *ast.CommentGroup, _ int) ast.Spec {
 	p.expectSemi() // call before accessing p.linecomment
 
 	// collect imports
-	spec := &ast.ImportSpec{doc, ident, path, p.lineComment}
+	spec := &ast.ImportSpec{doc, ident, path, p.lineComment, token.NoPos}
 	p.imports = append(p.imports, spec)
 
 	return spec
diff --git a/libgo/go/go/parser/parser_test.go b/libgo/go/go/parser/parser_test.go
index 9705dcf..dee90fbc 100644
--- a/libgo/go/go/parser/parser_test.go
+++ b/libgo/go/go/parser/parser_test.go
@@ -5,6 +5,7 @@
 package parser
 
 import (
+	"go/ast"
 	"go/token"
 	"os"
 	"testing"
@@ -134,3 +135,46 @@ func TestParse4(t *testing.T) {
 		}
 	}
 }
+
+func TestColonEqualsScope(t *testing.T) {
+	f, err := ParseFile(fset, "", `package p; func f() { x, y, z := x, y, z }`, 0)
+	if err != nil {
+		t.Errorf("parse: %s", err)
+	}
+
+	// RHS refers to undefined globals; LHS does not.
+	as := f.Decls[0].(*ast.FuncDecl).Body.List[0].(*ast.AssignStmt)
+	for _, v := range as.Rhs {
+		id := v.(*ast.Ident)
+		if id.Obj != nil {
+			t.Errorf("rhs %s has Obj, should not", id.Name)
+		}
+	}
+	for _, v := range as.Lhs {
+		id := v.(*ast.Ident)
+		if id.Obj == nil {
+			t.Errorf("lhs %s does not have Obj, should", id.Name)
+		}
+	}
+}
+
+func TestVarScope(t *testing.T) {
+	f, err := ParseFile(fset, "", `package p; func f() { var x, y, z = x, y, z }`, 0)
+	if err != nil {
+		t.Errorf("parse: %s", err)
+	}
+
+	// RHS refers to undefined globals; LHS does not.
+	as := f.Decls[0].(*ast.FuncDecl).Body.List[0].(*ast.DeclStmt).Decl.(*ast.GenDecl).Specs[0].(*ast.ValueSpec)
+	for _, v := range as.Values {
+		id := v.(*ast.Ident)
+		if id.Obj != nil {
+			t.Errorf("rhs %s has Obj, should not", id.Name)
+		}
+	}
+	for _, id := range as.Names {
+		if id.Obj == nil {
+			t.Errorf("lhs %s does not have Obj, should", id.Name)
+		}
+	}
+}
diff --git a/libgo/go/go/printer/nodes.go b/libgo/go/go/printer/nodes.go
index 3645306..248e43d 100644
--- a/libgo/go/go/printer/nodes.go
+++ b/libgo/go/go/printer/nodes.go
@@ -1278,6 +1278,7 @@ func (p *printer) spec(spec ast.Spec, n int, doIndent bool, multiLine *bool) {
 		}
 		p.expr(s.Path, multiLine)
 		p.setComment(s.Comment)
+		p.print(s.EndPos)
 
 	case *ast.ValueSpec:
 		if n != 1 {
diff --git a/libgo/go/go/scanner/errors.go b/libgo/go/go/scanner/errors.go
index a0927e4..df2a46b 100644
--- a/libgo/go/go/scanner/errors.go
+++ b/libgo/go/go/scanner/errors.go
@@ -92,7 +92,7 @@ func (p ErrorList) String() string {
 	case 1:
 		return p[0].String()
 	}
-	return fmt.Sprintf("%s (and %d more errors)", p[0].String(), len(p)-1)
+	return fmt.Sprintf("%s (and %d more errors)", p[0], len(p)-1)
 }
 
 // These constants control the construction of the ErrorList
diff --git a/libgo/go/go/scanner/scanner.go b/libgo/go/go/scanner/scanner.go
index 589ec68..dfbdaa3 100644
--- a/libgo/go/go/scanner/scanner.go
+++ b/libgo/go/go/scanner/scanner.go
@@ -43,7 +43,7 @@ type Scanner struct {
 	mode uint         // scanning mode
 
 	// scanning state
-	ch         int  // current character
+	ch         rune // current character
 	offset     int  // character offset
 	rdOffset   int  // reading offset (position after current character)
 	lineOffset int  // current line offset
@@ -63,7 +63,7 @@ func (S *Scanner) next() {
 			S.lineOffset = S.offset
 			S.file.AddLine(S.offset)
 		}
-		r, w := int(S.src[S.rdOffset]), 1
+		r, w := rune(S.src[S.rdOffset]), 1
 		switch {
 		case r == 0:
 			S.error(S.offset, "illegal character NUL")
@@ -232,11 +232,11 @@ func (S *Scanner) findLineEnd() bool {
 	return false
 }
 
-func isLetter(ch int) bool {
+func isLetter(ch rune) bool {
 	return 'a' <= ch && ch <= 'z' || 'A' <= ch && ch <= 'Z' || ch == '_' || ch >= 0x80 && unicode.IsLetter(ch)
 }
 
-func isDigit(ch int) bool {
+func isDigit(ch rune) bool {
 	return '0' <= ch && ch <= '9' || ch >= 0x80 && unicode.IsDigit(ch)
 }
 
@@ -248,14 +248,14 @@ func (S *Scanner) scanIdentifier() token.Token {
 	return token.Lookup(S.src[offs:S.offset])
 }
 
-func digitVal(ch int) int {
+func digitVal(ch rune) int {
 	switch {
 	case '0' <= ch && ch <= '9':
-		return ch - '0'
+		return int(ch - '0')
 	case 'a' <= ch && ch <= 'f':
-		return ch - 'a' + 10
+		return int(ch - 'a' + 10)
 	case 'A' <= ch && ch <= 'F':
-		return ch - 'A' + 10
+		return int(ch - 'A' + 10)
 	}
 	return 16 // larger than any legal digit val
 }
@@ -337,7 +337,7 @@ exit:
 	return tok
 }
 
-func (S *Scanner) scanEscape(quote int) {
+func (S *Scanner) scanEscape(quote rune) {
 	offs := S.offset
 
 	var i, base, max uint32
@@ -462,7 +462,7 @@ func (S *Scanner) switch2(tok0, tok1 token.Token) token.Token {
 	return tok0
 }
 
-func (S *Scanner) switch3(tok0, tok1 token.Token, ch2 int, tok2 token.Token) token.Token {
+func (S *Scanner) switch3(tok0, tok1 token.Token, ch2 rune, tok2 token.Token) token.Token {
 	if S.ch == '=' {
 		S.next()
 		return tok1
@@ -474,7 +474,7 @@ func (S *Scanner) switch3(tok0, tok1 token.Token, ch2 int, tok2 token.Token) tok
 	return tok0
 }
 
-func (S *Scanner) switch4(tok0, tok1 token.Token, ch2 int, tok2, tok3 token.Token) token.Token {
+func (S *Scanner) switch4(tok0, tok1 token.Token, ch2 rune, tok2, tok3 token.Token) token.Token {
 	if S.ch == '=' {
 		S.next()
 		return tok1
diff --git a/libgo/go/go/scanner/scanner_test.go b/libgo/go/go/scanner/scanner_test.go
index 0c2cbe6..7ed927a 100644
--- a/libgo/go/go/scanner/scanner_test.go
+++ b/libgo/go/go/scanner/scanner_test.go
@@ -237,7 +237,7 @@ func TestScan(t *testing.T) {
 		}
 		checkPos(t, lit, pos, epos)
 		if tok != e.tok {
-			t.Errorf("bad token for %q: got %s, expected %s", lit, tok.String(), e.tok.String())
+			t.Errorf("bad token for %q: got %s, expected %s", lit, tok, e.tok)
 		}
 		if e.tok.IsLiteral() && lit != e.lit {
 			t.Errorf("bad literal for %q: got %q, expected %q", lit, lit, e.lit)
@@ -286,7 +286,7 @@ func checkSemi(t *testing.T, line string, mode uint) {
 				}
 				checkPos(t, line, pos, semiPos)
 			} else {
-				t.Errorf("bad token for %q: got %s, expected ;", line, tok.String())
+				t.Errorf("bad token for %q: got %s, expected ;", line, tok)
 			}
 		} else if tok == token.SEMICOLON {
 			t.Errorf("bad token for %q: got ;, expected no ;", line)
@@ -509,7 +509,7 @@ func TestInit(t *testing.T) {
 	s.Scan()              // true
 	_, tok, _ := s.Scan() // {
 	if tok != token.LBRACE {
-		t.Errorf("bad token: got %s, expected %s", tok.String(), token.LBRACE)
+		t.Errorf("bad token: got %s, expected %s", tok, token.LBRACE)
 	}
 
 	// 2nd init
@@ -521,7 +521,7 @@ func TestInit(t *testing.T) {
 	}
 	_, tok, _ = s.Scan() // go
 	if tok != token.GO {
-		t.Errorf("bad token: got %s, expected %s", tok.String(), token.GO)
+		t.Errorf("bad token: got %s, expected %s", tok, token.GO)
 	}
 
 	if s.ErrorCount != 0 {
diff --git a/libgo/go/gob/codec_test.go b/libgo/go/gob/codec_test.go
index 2bcbf82..5306354 100644
--- a/libgo/go/gob/codec_test.go
+++ b/libgo/go/gob/codec_test.go
@@ -41,7 +41,7 @@ var encodeT = []EncodeT{
 // plain test.Error call.
 func testError(t *testing.T) {
 	if e := recover(); e != nil {
-		t.Error(e.(gobError).Error) // Will re-panic if not one of our errors, such as a runtime error.
+		t.Error(e.(gobError).err) // Will re-panic if not one of our errors, such as a runtime error.
 	}
 	return
 }
diff --git a/libgo/go/gob/decode.go b/libgo/go/gob/decode.go
index f480087..d027d3f 100644
--- a/libgo/go/gob/decode.go
+++ b/libgo/go/gob/decode.go
@@ -881,7 +881,7 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProg
 		}
 	}
 	if op == nil {
-		errorf("decode can't handle type %s", rt.String())
+		errorf("decode can't handle type %s", rt)
 	}
 	return &op, indir
 }
@@ -1110,7 +1110,7 @@ func (dec *Decoder) compileDec(remoteId typeId, ut *userTypeInfo) (engine *decEn
 		wireStruct = wire.StructT
 	}
 	if wireStruct == nil {
-		errorf("type mismatch in decoder: want struct type %s; got non-struct", rt.String())
+		errorf("type mismatch in decoder: want struct type %s; got non-struct", rt)
 	}
 	engine = new(decEngine)
 	engine.instr = make([]decInstr, len(wireStruct.Field))
diff --git a/libgo/go/gob/decoder.go b/libgo/go/gob/decoder.go
index 5efcea8..1d526e3 100644
--- a/libgo/go/gob/decoder.go
+++ b/libgo/go/gob/decoder.go
@@ -64,7 +64,7 @@ func (dec *Decoder) recvType(id typeId) {
 	dec.wireType[id] = wire
 }
 
-var errBadCount = gobError{os.NewError("invalid message length")}
+var errBadCount = os.NewError("invalid message length")
 
 // recvMessage reads the next count-delimited item from the input. It is the converse
 // of Encoder.writeMessage. It returns false on EOF or other error reading the message.
diff --git a/libgo/go/gob/encode.go b/libgo/go/gob/encode.go
index 6bb5458..c164435 100644
--- a/libgo/go/gob/encode.go
+++ b/libgo/go/gob/encode.go
@@ -610,7 +610,7 @@ func (enc *Encoder) encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp
 		}
 	}
 	if op == nil {
-		errorf("can't happen: encode type %s", rt.String())
+		errorf("can't happen: encode type %s", rt)
 	}
 	return &op, indir
 }
diff --git a/libgo/go/gob/encoder_test.go b/libgo/go/gob/encoder_test.go
index a774438..98c0c97 100644
--- a/libgo/go/gob/encoder_test.go
+++ b/libgo/go/gob/encoder_test.go
@@ -606,14 +606,14 @@ func TestSliceReusesMemory(t *testing.T) {
 	}
 	// general slice
 	{
-		x := []int("abcd")
+		x := []rune("abcd")
 		enc := NewEncoder(buf)
 		err := enc.Encode(x)
 		if err != nil {
 			t.Errorf("ints: encode: %s", err)
 		}
 		// Decode into y, which is big enough.
-		y := []int("ABCDE")
+		y := []rune("ABCDE")
 		addr := &y[0]
 		dec := NewDecoder(buf)
 		err = dec.Decode(&y)
diff --git a/libgo/go/gob/error.go b/libgo/go/gob/error.go
index bfd38fc..106543d 100644
--- a/libgo/go/gob/error.go
+++ b/libgo/go/gob/error.go
@@ -18,7 +18,7 @@ import (
 
 // A gobError wraps an os.Error and is used to distinguish errors (panics) generated in this package.
 type gobError struct {
-	os.Error
+	err os.Error
 }
 
 // errorf is like error but takes Printf-style arguments to construct an os.Error.
@@ -29,14 +29,14 @@ func errorf(format string, args ...interface{}) {
 
 // error wraps the argument error and uses it as the argument to panic.
 func error(err os.Error) {
-	panic(gobError{Error: err})
+	panic(gobError{err})
 }
 
 // catchError is meant to be used as a deferred function to turn a panic(gobError) into a
 // plain os.Error.  It overwrites the error return of the function that deferred its call.
 func catchError(err *os.Error) {
 	if e := recover(); e != nil {
-		*err = e.(gobError).Error // Will re-panic if not one of our errors, such as a runtime error.
+		*err = e.(gobError).err // Will re-panic if not one of our errors, such as a runtime error.
 	}
 	return
 }
diff --git a/libgo/go/html/entity.go b/libgo/go/html/entity.go
index 21263e2..bd83075 100644
--- a/libgo/go/html/entity.go
+++ b/libgo/go/html/entity.go
@@ -13,7 +13,7 @@ const longestEntityWithoutSemicolon = 6
 //
 // Note that the HTML5 list is larger than the HTML4 list at
 // http://www.w3.org/TR/html4/sgml/entities.html
-var entity = map[string]int{
+var entity = map[string]rune{
 	"AElig;":                           '\U000000C6',
 	"AMP;":                             '\U00000026',
 	"Aacute;":                          '\U000000C1',
@@ -2155,7 +2155,7 @@ var entity = map[string]int{
 }
 
 // HTML entities that are two unicode codepoints.
-var entity2 = map[string][2]int{
+var entity2 = map[string][2]rune{
 	// TODO(nigeltao): Handle replacements that are wider than their names.
 	// "nLt;":                     {'\u226A', '\u20D2'},
 	// "nGt;":                     {'\u226B', '\u20D2'},
diff --git a/libgo/go/html/escape.go b/libgo/go/html/escape.go
index e9edc47..69e0028 100644
--- a/libgo/go/html/escape.go
+++ b/libgo/go/html/escape.go
@@ -14,7 +14,7 @@ import (
 // These replacements permit compatibility with old numeric entities that 
 // assumed Windows-1252 encoding.
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/tokenization.html#consume-a-character-reference
-var replacementTable = [...]int{
+var replacementTable = [...]rune{
 	'\u20AC', // First entry is what 0x80 should be replaced with.
 	'\u0081',
 	'\u201A',
@@ -79,23 +79,23 @@ func unescapeEntity(b []byte, dst, src int, attribute bool) (dst1, src1 int) {
 			i++
 		}
 
-		x := 0
+		x := rune(0)
 		for i < len(s) {
 			c = s[i]
 			i++
 			if hex {
 				if '0' <= c && c <= '9' {
-					x = 16*x + int(c) - '0'
+					x = 16*x + rune(c) - '0'
 					continue
 				} else if 'a' <= c && c <= 'f' {
-					x = 16*x + int(c) - 'a' + 10
+					x = 16*x + rune(c) - 'a' + 10
 					continue
 				} else if 'A' <= c && c <= 'F' {
-					x = 16*x + int(c) - 'A' + 10
+					x = 16*x + rune(c) - 'A' + 10
 					continue
 				}
 			} else if '0' <= c && c <= '9' {
-				x = 10*x + int(c) - '0'
+				x = 10*x + rune(c) - '0'
 				continue
 			}
 			if c != ';' {
diff --git a/libgo/go/html/node.go b/libgo/go/html/node.go
index 4ecfd6c..5ca6035c 100644
--- a/libgo/go/html/node.go
+++ b/libgo/go/html/node.go
@@ -135,6 +135,8 @@ func (s *nodeStack) remove(n *Node) {
 	*s = (*s)[:j]
 }
 
+// TODO(nigeltao): forTag no longer used. Should it be deleted?
+
 // forTag returns the top-most element node with the given tag.
 func (s *nodeStack) forTag(tag string) *Node {
 	for i := len(*s) - 1; i >= 0; i-- {
diff --git a/libgo/go/html/parse.go b/libgo/go/html/parse.go
index 530942aa..54f7e2e 100644
--- a/libgo/go/html/parse.go
+++ b/libgo/go/html/parse.go
@@ -7,6 +7,7 @@ package html
 import (
 	"io"
 	"os"
+	"strings"
 )
 
 // A parser implements the HTML5 parsing algorithm:
@@ -125,6 +126,7 @@ func (p *parser) addChild(n *Node) {
 // fosterParent adds a child node according to the foster parenting rules.
 // Section 11.2.5.3, "foster parenting".
 func (p *parser) fosterParent(n *Node) {
+	p.fosterParenting = false
 	var table, parent *Node
 	var i int
 	for i = len(p.oe) - 1; i >= 0; i-- {
@@ -430,6 +432,8 @@ func beforeHeadIM(p *parser) (insertionMode, bool) {
 	return inHeadIM, !implied
 }
 
+const whitespace = " \t\r\n\f"
+
 // Section 11.2.5.4.4.
 func inHeadIM(p *parser) (insertionMode, bool) {
 	var (
@@ -437,13 +441,24 @@ func inHeadIM(p *parser) (insertionMode, bool) {
 		implied bool
 	)
 	switch p.tok.Type {
-	case ErrorToken, TextToken:
+	case ErrorToken:
+		implied = true
+	case TextToken:
+		s := strings.TrimLeft(p.tok.Data, whitespace)
+		if len(s) < len(p.tok.Data) {
+			// Add the initial whitespace to the current node.
+			p.addText(p.tok.Data[:len(p.tok.Data)-len(s)])
+			if s == "" {
+				return inHeadIM, true
+			}
+			p.tok.Data = s
+		}
 		implied = true
 	case StartTagToken:
 		switch p.tok.Data {
 		case "meta":
 			// TODO.
-		case "script", "title":
+		case "script", "title", "noscript", "noframes", "style":
 			p.addElement(p.tok.Data, p.tok.Attr)
 			p.setOriginalIM(inHeadIM)
 			return textIM, true
@@ -469,7 +484,7 @@ func inHeadIM(p *parser) (insertionMode, bool) {
 		}
 		return afterHeadIM, !implied
 	}
-	return inHeadIM, !implied
+	return inHeadIM, true
 }
 
 // Section 11.2.5.4.6.
@@ -538,10 +553,13 @@ func inBodyIM(p *parser) (insertionMode, bool) {
 			}
 			p.addElement(p.tok.Data, p.tok.Attr)
 		case "a":
-			if n := p.afe.forTag("a"); n != nil {
-				p.inBodyEndTagFormatting("a")
-				p.oe.remove(n)
-				p.afe.remove(n)
+			for i := len(p.afe) - 1; i >= 0 && p.afe[i].Type != scopeMarkerNode; i-- {
+				if n := p.afe[i]; n.Type == ElementNode && n.Data == "a" {
+					p.inBodyEndTagFormatting("a")
+					p.oe.remove(n)
+					p.afe.remove(n)
+					break
+				}
 			}
 			p.reconstructActiveFormattingElements()
 			p.addFormattingElement(p.tok.Data, p.tok.Attr)
@@ -594,6 +612,12 @@ func inBodyIM(p *parser) (insertionMode, bool) {
 			}
 			p.popUntil(buttonScopeStopTags, "p")
 			p.addElement("li", p.tok.Attr)
+		case "optgroup", "option":
+			if p.top().Data == "option" {
+				p.oe.pop()
+			}
+			p.reconstructActiveFormattingElements()
+			p.addElement(p.tok.Data, p.tok.Attr)
 		default:
 			// TODO.
 			p.addElement(p.tok.Data, p.tok.Attr)
@@ -655,6 +679,10 @@ func (p *parser) inBodyEndTagFormatting(tag string) {
 			p.afe.remove(formattingElement)
 			return
 		}
+		if !p.elementInScope(defaultScopeStopTags, tag) {
+			// Ignore the tag.
+			return
+		}
 
 		// Steps 5-6. Find the furthest block.
 		var furthestBlock *Node
@@ -732,6 +760,10 @@ func (p *parser) inBodyEndTagFormatting(tag string) {
 		furthestBlock.Add(clone)
 
 		// Step 14. Fix up the list of active formatting elements.
+		if oldLoc := p.afe.index(formattingElement); oldLoc != -1 && oldLoc < bookmark {
+			// Move the bookmark with the rest of the list.
+			bookmark--
+		}
 		p.afe.remove(formattingElement)
 		p.afe.insert(bookmark, clone)
 
@@ -757,6 +789,8 @@ func (p *parser) inBodyEndTagOther(tag string) {
 // Section 11.2.5.4.8.
 func textIM(p *parser) (insertionMode, bool) {
 	switch p.tok.Type {
+	case ErrorToken:
+		p.oe.pop()
 	case TextToken:
 		p.addText(p.tok.Data)
 		return textIM, true
@@ -956,7 +990,12 @@ func inCellIM(p *parser) (insertionMode, bool) {
 	case EndTagToken:
 		switch p.tok.Data {
 		case "td", "th":
-			// TODO.
+			if !p.popUntil(tableScopeStopTags, p.tok.Data) {
+				// Ignore the token.
+				return inCellIM, true
+			}
+			p.clearActiveFormattingElements()
+			return inRowIM, true
 		case "body", "caption", "col", "colgroup", "html":
 			// TODO.
 		case "table", "tbody", "tfoot", "thead", "tr":
diff --git a/libgo/go/html/parse_test.go b/libgo/go/html/parse_test.go
index b0ddd92..b9572fa 100644
--- a/libgo/go/html/parse_test.go
+++ b/libgo/go/html/parse_test.go
@@ -132,7 +132,7 @@ func TestParser(t *testing.T) {
 		rc := make(chan io.Reader)
 		go readDat(filename, rc)
 		// TODO(nigeltao): Process all test cases, not just a subset.
-		for i := 0; i < 34; i++ {
+		for i := 0; i < 80; i++ {
 			// Parse the #data section.
 			b, err := ioutil.ReadAll(<-rc)
 			if err != nil {
@@ -160,14 +160,10 @@ func TestParser(t *testing.T) {
 				t.Errorf("%s test #%d %q, got vs want:\n----\n%s----\n%s----", filename, i, text, got, want)
 				continue
 			}
-			// Check that rendering and re-parsing results in an identical tree.
-			if filename == "tests1.dat" && i == 30 {
-				// Test 30 in tests1.dat is such messed-up markup that a correct parse
-				// results in a non-conforming tree (one <a> element nested inside another).
-				// Therefore when it is rendered and re-parsed, it isn't the same.
-				// So we skip rendering on that test.
+			if renderTestBlacklist[text] {
 				continue
 			}
+			// Check that rendering and re-parsing results in an identical tree.
 			pr, pw := io.Pipe()
 			go func() {
 				pw.CloseWithError(Render(pw, doc))
@@ -187,3 +183,15 @@ func TestParser(t *testing.T) {
 		}
 	}
 }
+
+// Some test input result in parse trees are not 'well-formed' despite
+// following the HTML5 recovery algorithms. Rendering and re-parsing such a
+// tree will not result in an exact clone of that tree. We blacklist such
+// inputs from the render test.
+var renderTestBlacklist = map[string]bool{
+	// The second <a> will be reparented to the first <table>'s parent. This
+	// results in an <a> whose parent is an <a>, which is not 'well-formed'.
+	`<a><table><td><a><table></table><a></tr><a></table><b>X</b>C<a>Y`: true,
+	// The second <a> will be reparented, similar to the case above.
+	`<a href="blah">aba<table><a href="foo">br<tr><td></td></tr>x</table>aoe`: true,
+}
diff --git a/libgo/go/html/render.go b/libgo/go/html/render.go
index d5dc448..0522b6e 100644
--- a/libgo/go/html/render.go
+++ b/libgo/go/html/render.go
@@ -19,17 +19,28 @@ type writer interface {
 
 // Render renders the parse tree n to the given writer.
 //
-// For 'well-formed' parse trees, calling Parse on the output of Render will
-// result in a clone of the original tree.
+// Rendering is done on a 'best effort' basis: calling Parse on the output of
+// Render will always result in something similar to the original tree, but it
+// is not necessarily an exact clone unless the original tree was 'well-formed'.
+// 'Well-formed' is not easily specified; the HTML5 specification is
+// complicated.
 //
-// 'Well-formed' is not formally specified, but calling Parse on arbitrary
-// input results in a 'well-formed' parse tree if Parse does not return an
-// error. Programmatically constructed trees are typically also 'well-formed',
-// but it is possible to construct a tree that, when rendered and re-parsed,
-// results in a different tree. A simple example is that a solitary text node
-// would become a tree containing <html>, <head> and <body> elements. Another
-// example is that the programmatic equivalent of "a<head>b</head>c" becomes
-// "<html><head><head/><body>abc</body></html>".
+// Calling Parse on arbitrary input typically results in a 'well-formed' parse
+// tree. However, it is possible for Parse to yield a 'badly-formed' parse tree.
+// For example, in a 'well-formed' parse tree, no <a> element is a child of
+// another <a> element: parsing "<a><a>" results in two sibling elements.
+// Similarly, in a 'well-formed' parse tree, no <a> element is a child of a
+// <table> element: parsing "<p><table><a>" results in a <p> with two sibling
+// children; the <a> is reparented to the <table>'s parent. However, calling
+// Parse on "<a><table><a>" does not return an error, but the result has an <a>
+// element with an <a> child, and is therefore not 'well-formed'.
+// 
+// Programmatically constructed trees are typically also 'well-formed', but it
+// is possible to construct a tree that looks innocuous but, when rendered and
+// re-parsed, results in a different tree. A simple example is that a solitary
+// text node would become a tree containing <html>, <head> and <body> elements.
+// Another example is that the programmatic equivalent of "a<head>b</head>c"
+// becomes "<html><head><head/><body>abc</body></html>".
 func Render(w io.Writer, n *Node) os.Error {
 	if x, ok := w.(writer); ok {
 		return render(x, n)
diff --git a/libgo/go/html/token_test.go b/libgo/go/html/token_test.go
index 45ce85e..a5efdf2 100644
--- a/libgo/go/html/token_test.go
+++ b/libgo/go/html/token_test.go
@@ -439,7 +439,7 @@ loop:
 		}
 		z.Next()
 		if z.Error() != os.EOF {
-			t.Errorf("%s: want EOF got %q", tt.desc, z.Token().String())
+			t.Errorf("%s: want EOF got %q", tt.desc, z.Error())
 		}
 	}
 }
diff --git a/libgo/go/http/cgi/host.go b/libgo/go/http/cgi/host.go
index 9ea4c9d..365a712 100644
--- a/libgo/go/http/cgi/host.go
+++ b/libgo/go/http/cgi/host.go
@@ -333,18 +333,18 @@ func (h *Handler) handleInternalRedirect(rw http.ResponseWriter, req *http.Reque
 	h.PathLocationHandler.ServeHTTP(rw, newReq)
 }
 
-func upperCaseAndUnderscore(rune int) int {
+func upperCaseAndUnderscore(r rune) rune {
 	switch {
-	case rune >= 'a' && rune <= 'z':
-		return rune - ('a' - 'A')
-	case rune == '-':
+	case r >= 'a' && r <= 'z':
+		return r - ('a' - 'A')
+	case r == '-':
 		return '_'
-	case rune == '=':
+	case r == '=':
 		// Maybe not part of the CGI 'spec' but would mess up
 		// the environment in any case, as Go represents the
 		// environment as a slice of "key=value" strings.
 		return '_'
 	}
 	// TODO: other transformations in spec or practice?
-	return rune
+	return r
 }
diff --git a/libgo/go/http/reverseproxy.go b/libgo/go/http/reverseproxy.go
index 3f8bfdc..3a63db0 100644
--- a/libgo/go/http/reverseproxy.go
+++ b/libgo/go/http/reverseproxy.go
@@ -69,6 +69,14 @@ func NewSingleHostReverseProxy(target *url.URL) *ReverseProxy {
 	return &ReverseProxy{Director: director}
 }
 
+func copyHeader(dst, src Header) {
+	for k, vv := range src {
+		for _, v := range vv {
+			dst.Add(k, v)
+		}
+	}
+}
+
 func (p *ReverseProxy) ServeHTTP(rw ResponseWriter, req *Request) {
 	transport := p.Transport
 	if transport == nil {
@@ -84,6 +92,16 @@ func (p *ReverseProxy) ServeHTTP(rw ResponseWriter, req *Request) {
 	outreq.ProtoMinor = 1
 	outreq.Close = false
 
+	// Remove the connection header to the backend.  We want a
+	// persistent connection, regardless of what the client sent
+	// to us.  This is modifying the same underlying map from req
+	// (shallow copied above) so we only copy it if necessary.
+	if outreq.Header.Get("Connection") != "" {
+		outreq.Header = make(Header)
+		copyHeader(outreq.Header, req.Header)
+		outreq.Header.Del("Connection")
+	}
+
 	if clientIp, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
 		outreq.Header.Set("X-Forwarded-For", clientIp)
 	}
@@ -95,12 +113,7 @@ func (p *ReverseProxy) ServeHTTP(rw ResponseWriter, req *Request) {
 		return
 	}
 
-	hdr := rw.Header()
-	for k, vv := range res.Header {
-		for _, v := range vv {
-			hdr.Add(k, v)
-		}
-	}
+	copyHeader(rw.Header(), res.Header)
 
 	rw.WriteHeader(res.StatusCode)
 
diff --git a/libgo/go/http/reverseproxy_test.go b/libgo/go/http/reverseproxy_test.go
index 8078c8d..663218d 100644
--- a/libgo/go/http/reverseproxy_test.go
+++ b/libgo/go/http/reverseproxy_test.go
@@ -24,6 +24,9 @@ func TestReverseProxy(t *testing.T) {
 		if r.Header.Get("X-Forwarded-For") == "" {
 			t.Errorf("didn't get X-Forwarded-For header")
 		}
+		if c := r.Header.Get("Connection"); c != "" {
+			t.Errorf("handler got Connection header value %q", c)
+		}
 		if g, e := r.Host, "some-name"; g != e {
 			t.Errorf("backend got Host header %q, want %q", g, e)
 		}
@@ -43,6 +46,8 @@ func TestReverseProxy(t *testing.T) {
 
 	getReq, _ := NewRequest("GET", frontend.URL, nil)
 	getReq.Host = "some-name"
+	getReq.Header.Set("Connection", "close")
+	getReq.Close = true
 	res, err := DefaultClient.Do(getReq)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
diff --git a/libgo/go/io/io.go b/libgo/go/io/io.go
index 5520634..07e2bce 100644
--- a/libgo/go/io/io.go
+++ b/libgo/go/io/io.go
@@ -194,7 +194,7 @@ type ByteScanner interface {
 // and returns the rune and its size in bytes. If no character is
 // available, err will be set.
 type RuneReader interface {
-	ReadRune() (rune int, size int, err os.Error)
+	ReadRune() (r rune, size int, err os.Error)
 }
 
 // RuneScanner is the interface that adds the UnreadRune method to the
diff --git a/libgo/go/json/decode.go b/libgo/go/json/decode.go
index 31b15a4..800df98 100644
--- a/libgo/go/json/decode.go
+++ b/libgo/go/json/decode.go
@@ -588,7 +588,7 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value) {
 		switch v.Kind() {
 		default:
 			d.saveError(&UnmarshalTypeError{"null", v.Type()})
-		case reflect.Interface, reflect.Ptr, reflect.Map:
+		case reflect.Interface, reflect.Ptr, reflect.Map, reflect.Slice:
 			v.Set(reflect.Zero(v.Type()))
 		}
 
@@ -805,15 +805,15 @@ func (d *decodeState) literalInterface() interface{} {
 
 // getu4 decodes \uXXXX from the beginning of s, returning the hex value,
 // or it returns -1.
-func getu4(s []byte) int {
+func getu4(s []byte) rune {
 	if len(s) < 6 || s[0] != '\\' || s[1] != 'u' {
 		return -1
 	}
-	rune, err := strconv.Btoui64(string(s[2:6]), 16)
+	r, err := strconv.Btoui64(string(s[2:6]), 16)
 	if err != nil {
 		return -1
 	}
-	return int(rune)
+	return rune(r)
 }
 
 // unquote converts a quoted JSON string literal s into an actual string t.
@@ -843,8 +843,8 @@ func unquoteBytes(s []byte) (t []byte, ok bool) {
 			r++
 			continue
 		}
-		rune, size := utf8.DecodeRune(s[r:])
-		if rune == utf8.RuneError && size == 1 {
+		rr, size := utf8.DecodeRune(s[r:])
+		if rr == utf8.RuneError && size == 1 {
 			break
 		}
 		r += size
@@ -899,23 +899,23 @@ func unquoteBytes(s []byte) (t []byte, ok bool) {
 				w++
 			case 'u':
 				r--
-				rune := getu4(s[r:])
-				if rune < 0 {
+				rr := getu4(s[r:])
+				if rr < 0 {
 					return
 				}
 				r += 6
-				if utf16.IsSurrogate(rune) {
-					rune1 := getu4(s[r:])
-					if dec := utf16.DecodeRune(rune, rune1); dec != unicode.ReplacementChar {
+				if utf16.IsSurrogate(rr) {
+					rr1 := getu4(s[r:])
+					if dec := utf16.DecodeRune(rr, rr1); dec != unicode.ReplacementChar {
 						// A valid pair; consume.
 						r += 6
 						w += utf8.EncodeRune(b[w:], dec)
 						break
 					}
 					// Invalid surrogate; fall back to replacement rune.
-					rune = unicode.ReplacementChar
+					rr = unicode.ReplacementChar
 				}
-				w += utf8.EncodeRune(b[w:], rune)
+				w += utf8.EncodeRune(b[w:], rr)
 			}
 
 		// Quote, control characters are invalid.
@@ -930,9 +930,9 @@ func unquoteBytes(s []byte) (t []byte, ok bool) {
 
 		// Coerce to well-formed UTF-8.
 		default:
-			rune, size := utf8.DecodeRune(s[r:])
+			rr, size := utf8.DecodeRune(s[r:])
 			r += size
-			w += utf8.EncodeRune(b[w:], rune)
+			w += utf8.EncodeRune(b[w:], rr)
 		}
 	}
 	return b[0:w], true
diff --git a/libgo/go/json/decode_test.go b/libgo/go/json/decode_test.go
index 2c7cbc4..d745e8dd 100644
--- a/libgo/go/json/decode_test.go
+++ b/libgo/go/json/decode_test.go
@@ -243,7 +243,7 @@ func TestHTMLEscape(t *testing.T) {
 	}
 }
 
-func noSpace(c int) int {
+func noSpace(c rune) rune {
 	if isSpace(c) {
 		return -1
 	}
@@ -456,7 +456,7 @@ var allValueIndent = `{
 	"PSlice": null,
 	"PSliceP": null,
 	"EmptySlice": [],
-	"NilSlice": [],
+	"NilSlice": null,
 	"StringSlice": [
 		"str24",
 		"str25",
@@ -528,8 +528,8 @@ var pallValueIndent = `{
 	},
 	"EmptyMap": null,
 	"NilMap": null,
-	"Slice": [],
-	"SliceP": [],
+	"Slice": null,
+	"SliceP": null,
 	"PSlice": [
 		{
 			"Tag": "tag20"
@@ -547,10 +547,10 @@ var pallValueIndent = `{
 			"Tag": "tag23"
 		}
 	],
-	"EmptySlice": [],
-	"NilSlice": [],
-	"StringSlice": [],
-	"ByteSlice": "",
+	"EmptySlice": null,
+	"NilSlice": null,
+	"StringSlice": null,
+	"ByteSlice": null,
 	"Small": {
 		"Tag": ""
 	},
diff --git a/libgo/go/json/encode.go b/libgo/go/json/encode.go
index 46abe436..ba5c15c 100644
--- a/libgo/go/json/encode.go
+++ b/libgo/go/json/encode.go
@@ -352,7 +352,15 @@ func (e *encodeState) reflectValueQuoted(v reflect.Value, quoted bool) {
 		}
 		e.WriteByte('}')
 
-	case reflect.Array, reflect.Slice:
+	case reflect.Slice:
+		if v.IsNil() {
+			e.WriteString("null")
+			break
+		}
+		// Slices can be marshalled as nil, but otherwise are handled
+		// as arrays.
+		fallthrough
+	case reflect.Array:
 		if v.Type() == byteSliceType {
 			e.WriteByte('"')
 			s := v.Interface().([]byte)
diff --git a/libgo/go/json/encode_test.go b/libgo/go/json/encode_test.go
index f85bb62..92f266a 100644
--- a/libgo/go/json/encode_test.go
+++ b/libgo/go/json/encode_test.go
@@ -28,7 +28,7 @@ type Optionals struct {
 var optionalsExpected = `{
  "sr": "",
  "omitempty": 0,
- "slr": [],
+ "slr": null,
  "mr": {}
 }`
 
diff --git a/libgo/go/json/scanner.go b/libgo/go/json/scanner.go
index 49c2edd..1a39b4c 100644
--- a/libgo/go/json/scanner.go
+++ b/libgo/go/json/scanner.go
@@ -176,7 +176,7 @@ func (s *scanner) popParseState() {
 	}
 }
 
-func isSpace(c int) bool {
+func isSpace(c rune) bool {
 	return c == ' ' || c == '\t' || c == '\r' || c == '\n'
 }
 
diff --git a/libgo/go/json/scanner_test.go b/libgo/go/json/scanner_test.go
index 4d73eac..40bf295 100644
--- a/libgo/go/json/scanner_test.go
+++ b/libgo/go/json/scanner_test.go
@@ -261,13 +261,13 @@ func genValue(n int) interface{} {
 
 func genString(stddev float64) string {
 	n := int(math.Abs(rand.NormFloat64()*stddev + stddev/2))
-	c := make([]int, n)
+	c := make([]rune, n)
 	for i := range c {
 		f := math.Abs(rand.NormFloat64()*64 + 32)
 		if f > 0x10ffff {
 			f = 0x10ffff
 		}
-		c[i] = int(f)
+		c[i] = rune(f)
 	}
 	return string(c)
 }
diff --git a/libgo/go/json/stream.go b/libgo/go/json/stream.go
index f143b3f..98cb793 100644
--- a/libgo/go/json/stream.go
+++ b/libgo/go/json/stream.go
@@ -115,7 +115,7 @@ Input:
 
 func nonSpace(b []byte) bool {
 	for _, c := range b {
-		if !isSpace(int(c)) {
+		if !isSpace(rune(c)) {
 			return true
 		}
 	}
diff --git a/libgo/go/mail/message.go b/libgo/go/mail/message.go
index e227d17..29249fb 100644
--- a/libgo/go/mail/message.go
+++ b/libgo/go/mail/message.go
@@ -454,7 +454,7 @@ func decodeRFC2047Word(s string) (string, os.Error) {
 	case "iso-8859-1":
 		b := new(bytes.Buffer)
 		for _, c := range dec {
-			b.WriteRune(int(c))
+			b.WriteRune(rune(c))
 		}
 		return b.String(), nil
 	case "utf-8":
diff --git a/libgo/go/math/all_test.go b/libgo/go/math/all_test.go
index 94ddea2..b540b17 100644
--- a/libgo/go/math/all_test.go
+++ b/libgo/go/math/all_test.go
@@ -1709,7 +1709,7 @@ func TestCopysign(t *testing.T) {
 
 func TestCos(t *testing.T) {
 	for i := 0; i < len(vf); i++ {
-		if f := Cos(vf[i]); !close(cos[i], f) {
+		if f := Cos(vf[i]); !veryclose(cos[i], f) {
 			t.Errorf("Cos(%g) = %g, want %g", vf[i], f, cos[i])
 		}
 	}
@@ -2192,7 +2192,7 @@ func TestSignbit(t *testing.T) {
 }
 func TestSin(t *testing.T) {
 	for i := 0; i < len(vf); i++ {
-		if f := Sin(vf[i]); !close(sin[i], f) {
+		if f := Sin(vf[i]); !veryclose(sin[i], f) {
 			t.Errorf("Sin(%g) = %g, want %g", vf[i], f, sin[i])
 		}
 	}
@@ -2205,7 +2205,7 @@ func TestSin(t *testing.T) {
 
 func TestSincos(t *testing.T) {
 	for i := 0; i < len(vf); i++ {
-		if s, c := Sincos(vf[i]); !close(sin[i], s) || !close(cos[i], c) {
+		if s, c := Sincos(vf[i]); !veryclose(sin[i], s) || !veryclose(cos[i], c) {
 			t.Errorf("Sincos(%g) = %g, %g want %g, %g", vf[i], s, c, sin[i], cos[i])
 		}
 	}
diff --git a/libgo/go/math/sin.go b/libgo/go/math/sin.go
index 8a2edd7..9e553a2 100644
--- a/libgo/go/math/sin.go
+++ b/libgo/go/math/sin.go
@@ -1,4 +1,4 @@
-// Copyright 2009 The Go Authors. All rights reserved.
+// Copyright 2011 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.
 
@@ -6,60 +6,218 @@ package math
 
 /*
 	Floating-point sine and cosine.
-
-	Coefficients are #5077 from Hart & Cheney. (18.80D)
 */
 
-func sinus(x float64, quad int) float64 {
+// The original C code, the long comment, and the constants
+// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
+// available from http://www.netlib.org/cephes/cmath.tgz.
+// The go code is a simplified version of the original C.
+//
+//      sin.c
+//
+//      Circular sine
+//
+// SYNOPSIS:
+//
+// double x, y, sin();
+// y = sin( x );
+//
+// DESCRIPTION:
+//
+// Range reduction is into intervals of pi/4.  The reduction error is nearly
+// eliminated by contriving an extended precision modular arithmetic.
+//
+// Two polynomial approximating functions are employed.
+// Between 0 and pi/4 the sine is approximated by
+//      x  +  x**3 P(x**2).
+// Between pi/4 and pi/2 the cosine is represented as
+//      1  -  x**2 Q(x**2).
+//
+// ACCURACY:
+//
+//                      Relative error:
+// arithmetic   domain      # trials      peak         rms
+//    DEC       0, 10       150000       3.0e-17     7.8e-18
+//    IEEE -1.07e9,+1.07e9  130000       2.1e-16     5.4e-17
+//
+// Partial loss of accuracy begins to occur at x = 2**30 = 1.074e9.  The loss
+// is not gradual, but jumps suddenly to about 1 part in 10e7.  Results may
+// be meaningless for x > 2**49 = 5.6e14.
+//
+//      cos.c
+//
+//      Circular cosine
+//
+// SYNOPSIS:
+//
+// double x, y, cos();
+// y = cos( x );
+//
+// DESCRIPTION:
+//
+// Range reduction is into intervals of pi/4.  The reduction error is nearly
+// eliminated by contriving an extended precision modular arithmetic.
+//
+// Two polynomial approximating functions are employed.
+// Between 0 and pi/4 the cosine is approximated by
+//      1  -  x**2 Q(x**2).
+// Between pi/4 and pi/2 the sine is represented as
+//      x  +  x**3 P(x**2).
+//
+// ACCURACY:
+//
+//                      Relative error:
+// arithmetic   domain      # trials      peak         rms
+//    IEEE -1.07e9,+1.07e9  130000       2.1e-16     5.4e-17
+//    DEC        0,+1.07e9   17000       3.0e-17     7.2e-18
+//
+// Cephes Math Library Release 2.8:  June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+//    Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+//   The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+//   Stephen L. Moshier
+//   moshier@na-net.ornl.gov
+
+// sin coefficients
+var _sin = [...]float64{
+	1.58962301576546568060E-10, // 0x3de5d8fd1fd19ccd
+	-2.50507477628578072866E-8, // 0xbe5ae5e5a9291f5d
+	2.75573136213857245213E-6,  // 0x3ec71de3567d48a1
+	-1.98412698295895385996E-4, // 0xbf2a01a019bfdf03
+	8.33333333332211858878E-3,  // 0x3f8111111110f7d0
+	-1.66666666666666307295E-1, // 0xbfc5555555555548
+}
+// cos coefficients
+var _cos = [...]float64{
+	-1.13585365213876817300E-11, // 0xbda8fa49a0861a9b
+	2.08757008419747316778E-9,   // 0x3e21ee9d7b4e3f05
+	-2.75573141792967388112E-7,  // 0xbe927e4f7eac4bc6
+	2.48015872888517045348E-5,   // 0x3efa01a019c844f5
+	-1.38888888888730564116E-3,  // 0xbf56c16c16c14f91
+	4.16666666666665929218E-2,   // 0x3fa555555555554b
+}
+
+// Cos returns the cosine of x.
+//
+// Special conditions are:
+//	Cos(±Inf) = NaN
+//	Cos(NaN) = NaN
+func Cos(x float64) float64 {
 	const (
-		P0 = .1357884097877375669092680e8
-		P1 = -.4942908100902844161158627e7
-		P2 = .4401030535375266501944918e6
-		P3 = -.1384727249982452873054457e5
-		P4 = .1459688406665768722226959e3
-		Q0 = .8644558652922534429915149e7
-		Q1 = .4081792252343299749395779e6
-		Q2 = .9463096101538208180571257e4
-		Q3 = .1326534908786136358911494e3
+		PI4A = 7.85398125648498535156E-1                             // 0x3fe921fb40000000, Pi/4 split into three parts
+		PI4B = 3.77489470793079817668E-8                             // 0x3e64442d00000000,
+		PI4C = 2.69515142907905952645E-15                            // 0x3ce8469898cc5170,
+		M4PI = 1.273239544735162542821171882678754627704620361328125 // 4/pi
 	)
+	// TODO(rsc): Remove manual inlining of IsNaN, IsInf
+	// when compiler does it for us
+	// special cases
+	switch {
+	case x != x || x < -MaxFloat64 || x > MaxFloat64: // IsNaN(x) || IsInf(x, 0):
+		return NaN()
+	}
+
+	// make argument positive
+	sign := false
 	if x < 0 {
 		x = -x
-		quad = quad + 2
 	}
-	x = x * (2 / Pi) /* underflow? */
-	var y float64
-	if x > 32764 {
-		var e float64
-		e, y = Modf(x)
-		e = e + float64(quad)
-		f, _ := Modf(0.25 * e)
-		quad = int(e - 4*f)
-	} else {
-		k := int32(x)
-		y = x - float64(k)
-		quad = (quad + int(k)) & 3
+
+	j := int64(x * M4PI) // integer part of x/(Pi/4), as integer for tests on the phase angle
+	y := float64(j)      // integer part of x/(Pi/4), as float
+
+	// map zeros to origin
+	if j&1 == 1 {
+		j += 1
+		y += 1
+	}
+	j &= 7 // octant modulo 2Pi radians (360 degrees)
+	if j > 3 {
+		j -= 4
+		sign = !sign
+	}
+	if j > 1 {
+		sign = !sign
 	}
 
-	if quad&1 != 0 {
-		y = 1 - y
+	z := ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
+	zz := z * z
+	if j == 1 || j == 2 {
+		y = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
+	} else {
+		y = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
 	}
-	if quad > 1 {
+	if sign {
 		y = -y
 	}
-
-	yy := y * y
-	temp1 := ((((P4*yy+P3)*yy+P2)*yy+P1)*yy + P0) * y
-	temp2 := ((((yy+Q3)*yy+Q2)*yy+Q1)*yy + Q0)
-	return temp1 / temp2
+	return y
 }
 
-// Cos returns the cosine of x.
-func Cos(x float64) float64 {
+// Sin returns the sine of x.
+//
+// Special conditions are:
+//	Sin(±0) = ±0
+//	Sin(±Inf) = NaN
+//	Sin(NaN) = NaN
+func Sin(x float64) float64 {
+	const (
+		PI4A = 7.85398125648498535156E-1                             // 0x3fe921fb40000000, Pi/4 split into three parts
+		PI4B = 3.77489470793079817668E-8                             // 0x3e64442d00000000,
+		PI4C = 2.69515142907905952645E-15                            // 0x3ce8469898cc5170,
+		M4PI = 1.273239544735162542821171882678754627704620361328125 // 4/pi
+	)
+	// TODO(rsc): Remove manual inlining of IsNaN, IsInf
+	// when compiler does it for us
+	// special cases
+	switch {
+	case x == 0 || x != x: // x == 0 || IsNaN():
+		return x // return ±0 || NaN()
+	case x < -MaxFloat64 || x > MaxFloat64: // IsInf(x, 0):
+		return NaN()
+	}
+
+	// make argument positive but save the sign
+	sign := false
 	if x < 0 {
 		x = -x
+		sign = true
 	}
-	return sinus(x, 1)
-}
 
-// Sin returns the sine of x.
-func Sin(x float64) float64 { return sinus(x, 0) }
+	j := int64(x * M4PI) // integer part of x/(Pi/4), as integer for tests on the phase angle
+	y := float64(j)      // integer part of x/(Pi/4), as float
+
+	// map zeros to origin
+	if j&1 == 1 {
+		j += 1
+		y += 1
+	}
+	j &= 7 // octant modulo 2Pi radians (360 degrees)
+	// reflect in x axis
+	if j > 3 {
+		sign = !sign
+		j -= 4
+	}
+
+	z := ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
+	zz := z * z
+	if j == 1 || j == 2 {
+		y = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
+	} else {
+		y = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
+	}
+	if sign {
+		y = -y
+	}
+	return y
+}
diff --git a/libgo/go/mime/grammar.go b/libgo/go/mime/grammar.go
index 70a94cd..e16a06c 100644
--- a/libgo/go/mime/grammar.go
+++ b/libgo/go/mime/grammar.go
@@ -10,16 +10,16 @@ import (
 
 // isTSpecial returns true if rune is in 'tspecials' as defined by RFC
 // 1521 and RFC 2045.
-func isTSpecial(rune int) bool {
-	return strings.IndexRune(`()<>@,;:\"/[]?=`, rune) != -1
+func isTSpecial(r rune) bool {
+	return strings.IndexRune(`()<>@,;:\"/[]?=`, r) != -1
 }
 
 // IsTokenChar returns true if rune is in 'token' as defined by RFC
 // 1521 and RFC 2045.
-func IsTokenChar(rune int) bool {
+func IsTokenChar(r rune) bool {
 	// token := 1*<any (US-ASCII) CHAR except SPACE, CTLs,
 	//             or tspecials>
-	return rune > 0x20 && rune < 0x7f && !isTSpecial(rune)
+	return r > 0x20 && r < 0x7f && !isTSpecial(r)
 }
 
 // IsToken returns true if s is a 'token' as as defined by RFC 1521
@@ -32,14 +32,14 @@ func IsToken(s string) bool {
 }
 
 // IsQText returns true if rune is in 'qtext' as defined by RFC 822.
-func IsQText(rune int) bool {
+func IsQText(r int) bool {
 	// CHAR        =  <any ASCII character>        ; (  0-177,  0.-127.)
 	// qtext       =  <any CHAR excepting <">,     ; => may be folded
 	//                "\" & CR, and including
 	//                linear-white-space>
-	switch rune {
+	switch r {
 	case '"', '\\', '\r':
 		return false
 	}
-	return rune < 0x80
+	return r < 0x80
 }
diff --git a/libgo/go/mime/mediatype.go b/libgo/go/mime/mediatype.go
index b0d3933..8ad8004 100644
--- a/libgo/go/mime/mediatype.go
+++ b/libgo/go/mime/mediatype.go
@@ -199,8 +199,8 @@ func decode2231Enc(v string) string {
 	return encv
 }
 
-func isNotTokenChar(rune int) bool {
-	return !IsTokenChar(rune)
+func isNotTokenChar(r rune) bool {
+	return !IsTokenChar(r)
 }
 
 // consumeToken consumes a token from the beginning of provided
@@ -228,24 +228,25 @@ func consumeValue(v string) (value, rest string) {
 		return consumeToken(v)
 	}
 
-	leadQuote := int(v[0])
+	leadQuote := rune(v[0])
 
 	// parse a quoted-string
 	rest = v[1:] // consume the leading quote
 	buffer := new(bytes.Buffer)
-	var idx, rune int
+	var idx int
+	var r rune
 	var nextIsLiteral bool
-	for idx, rune = range rest {
+	for idx, r = range rest {
 		switch {
 		case nextIsLiteral:
-			buffer.WriteRune(rune)
+			buffer.WriteRune(r)
 			nextIsLiteral = false
-		case rune == leadQuote:
+		case r == leadQuote:
 			return buffer.String(), rest[idx+1:]
-		case rune == '\\':
+		case r == '\\':
 			nextIsLiteral = true
-		case rune != '\r' && rune != '\n':
-			buffer.WriteRune(rune)
+		case r != '\r' && r != '\n':
+			buffer.WriteRune(r)
 		default:
 			return "", v
 		}
diff --git a/libgo/go/net/lookup_plan9.go b/libgo/go/net/lookup_plan9.go
index d779f4a..a14c592 100644
--- a/libgo/go/net/lookup_plan9.go
+++ b/libgo/go/net/lookup_plan9.go
@@ -49,7 +49,7 @@ func queryCS(net, host, service string) (res []string, err os.Error) {
 
 func queryCS1(net string, ip IP, port int) (clone, dest string, err os.Error) {
 	ips := "*"
-	if !ip.IsUnspecified() {
+	if len(ip) != 0 && !ip.IsUnspecified() {
 		ips = ip.String()
 	}
 	lines, err := queryCS(net, ips, itoa(port))
@@ -215,7 +215,16 @@ func LookupMX(name string) (mx []*MX, err os.Error) {
 
 // LookupTXT returns the DNS TXT records for the given domain name.
 func LookupTXT(name string) (txt []string, err os.Error) {
-	return nil, os.NewError("net.LookupTXT is not implemented on Plan 9")
+	lines, err := queryDNS(name, "txt")
+	if err != nil {
+		return
+	}
+	for _, line := range lines {
+		if i := byteIndex(line, '\t'); i >= 0 {
+			txt = append(txt, line[i+1:])
+		}
+	}
+	return
 }
 
 // LookupAddr performs a reverse lookup for the given address, returning a list
diff --git a/libgo/go/net/lookup_test.go b/libgo/go/net/lookup_test.go
index c0fcd26..6b7e53d 100644
--- a/libgo/go/net/lookup_test.go
+++ b/libgo/go/net/lookup_test.go
@@ -52,8 +52,8 @@ func TestGmailMX(t *testing.T) {
 }
 
 func TestGmailTXT(t *testing.T) {
-	if runtime.GOOS == "windows" || runtime.GOOS == "plan9" {
-		t.Logf("LookupTXT is not implemented on Windows or Plan 9")
+	if runtime.GOOS == "windows" {
+		t.Logf("LookupTXT is not implemented on Windows")
 		return
 	}
 	if testing.Short() || avoidMacFirewall {
diff --git a/libgo/go/net/net_test.go b/libgo/go/net/net_test.go
index b4a6e1f..51cdac9 100644
--- a/libgo/go/net/net_test.go
+++ b/libgo/go/net/net_test.go
@@ -8,6 +8,7 @@ import (
 	"flag"
 	"os"
 	"regexp"
+	"runtime"
 	"testing"
 )
 
@@ -128,6 +129,9 @@ func TestReverseAddress(t *testing.T) {
 }
 
 func TestShutdown(t *testing.T) {
+	if runtime.GOOS == "plan9" {
+		return
+	}
 	l, err := Listen("tcp", "127.0.0.1:0")
 	if err != nil {
 		if l, err = Listen("tcp6", "[::1]:0"); err != nil {
diff --git a/libgo/go/net/sock_windows.go b/libgo/go/net/sock_windows.go
index 5169d1e..9b9cd9e 100644
--- a/libgo/go/net/sock_windows.go
+++ b/libgo/go/net/sock_windows.go
@@ -11,6 +11,13 @@ import (
 )
 
 func setKernelSpecificSockopt(s syscall.Handle, f int) {
+	// Windows will reuse recently-used addresses by default.
+	// SO_REUSEADDR should not be used here, as it allows
+	// a socket to forcibly bind to a port in use by another socket.
+	// This could lead to a non-deterministic behavior, where
+	// connection requests over the port cannot be guaranteed
+	// to be handled by the correct socket.
+
 	// Allow broadcast.
 	syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_BROADCAST, 1)
 
diff --git a/libgo/go/net/tcpsock_plan9.go b/libgo/go/net/tcpsock_plan9.go
index f4f6e9f..3319e57 100644
--- a/libgo/go/net/tcpsock_plan9.go
+++ b/libgo/go/net/tcpsock_plan9.go
@@ -16,6 +16,24 @@ type TCPConn struct {
 	plan9Conn
 }
 
+// CloseRead shuts down the reading side of the TCP connection.
+// Most callers should just use Close.
+func (c *TCPConn) CloseRead() os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return os.EPLAN9
+}
+
+// CloseWrite shuts down the writing side of the TCP connection.
+// Most callers should just use Close.
+func (c *TCPConn) CloseWrite() os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return os.EPLAN9
+}
+
 // DialTCP connects to the remote address raddr on the network net,
 // which must be "tcp", "tcp4", or "tcp6".  If laddr is not nil, it is used
 // as the local address for the connection.
diff --git a/libgo/go/net/textproto/reader.go b/libgo/go/net/textproto/reader.go
index ece9a99..98b3927 100644
--- a/libgo/go/net/textproto/reader.go
+++ b/libgo/go/net/textproto/reader.go
@@ -50,8 +50,22 @@ func (r *Reader) ReadLineBytes() ([]byte, os.Error) {
 
 func (r *Reader) readLineSlice() ([]byte, os.Error) {
 	r.closeDot()
-	line, _, err := r.R.ReadLine()
-	return line, err
+	var line []byte
+	for {
+		l, more, err := r.R.ReadLine()
+		if err != nil {
+			return nil, err
+		}
+		// Avoid the copy if the first call produced a full line.
+		if line == nil && !more {
+			return l, nil
+		}
+		line = append(line, l...)
+		if !more {
+			break
+		}
+	}
+	return line, nil
 }
 
 // ReadContinuedLine reads a possibly continued line from r,
diff --git a/libgo/go/net/textproto/reader_test.go b/libgo/go/net/textproto/reader_test.go
index 23ebc3f..a087e29 100644
--- a/libgo/go/net/textproto/reader_test.go
+++ b/libgo/go/net/textproto/reader_test.go
@@ -139,6 +139,23 @@ func TestReadMIMEHeader(t *testing.T) {
 	}
 }
 
+func TestLargeReadMIMEHeader(t *testing.T) {
+	data := make([]byte, 16*1024)
+	for i := 0; i < len(data); i++ {
+		data[i] = 'x'
+	}
+	sdata := string(data)
+	r := reader("Cookie: " + sdata + "\r\n\n")
+	m, err := r.ReadMIMEHeader()
+	if err != nil {
+		t.Fatalf("ReadMIMEHeader: %v", err)
+	}
+	cookie := m.Get("Cookie")
+	if cookie != sdata {
+		t.Fatalf("ReadMIMEHeader: %v bytes, want %v bytes", len(cookie), len(sdata))
+	}
+}
+
 type readResponseTest struct {
 	in       string
 	inCode   int
diff --git a/libgo/go/net/timeout_test.go b/libgo/go/net/timeout_test.go
index 0dbab58..2c2c36fff 100644
--- a/libgo/go/net/timeout_test.go
+++ b/libgo/go/net/timeout_test.go
@@ -6,6 +6,7 @@ package net
 
 import (
 	"os"
+	"runtime"
 	"testing"
 	"time"
 )
@@ -41,11 +42,17 @@ func testTimeout(t *testing.T, network, addr string, readFrom bool) {
 }
 
 func TestTimeoutUDP(t *testing.T) {
+	if runtime.GOOS == "plan9" {
+		return
+	}
 	testTimeout(t, "udp", "127.0.0.1:53", false)
 	testTimeout(t, "udp", "127.0.0.1:53", true)
 }
 
 func TestTimeoutTCP(t *testing.T) {
+	if runtime.GOOS == "plan9" {
+		return
+	}
 	// set up a listener that won't talk back
 	listening := make(chan string)
 	done := make(chan int)
diff --git a/libgo/go/old/regexp/regexp.go b/libgo/go/old/regexp/regexp.go
index e8d4c08..f18d9c8 100644
--- a/libgo/go/old/regexp/regexp.go
+++ b/libgo/go/old/regexp/regexp.go
@@ -119,7 +119,7 @@ type instr struct {
 	index int    // used only in debugging; could be eliminated
 	next  *instr // the instruction to execute after this one
 	// Special fields valid only for some items.
-	char   int        // iChar
+	char   rune       // iChar
 	braNum int        // iBra, iEbra
 	cclass *charClass // iCharClass
 	left   *instr     // iAlt, other branch
@@ -172,8 +172,8 @@ type Regexp struct {
 type charClass struct {
 	negate bool // is character class negated? ([^a-z])
 	// slice of int, stored pairwise: [a-z] is (a,z); x is (x,x):
-	ranges     []int
-	cmin, cmax int
+	ranges     []rune
+	cmin, cmax rune
 }
 
 func (cclass *charClass) print() {
@@ -192,7 +192,7 @@ func (cclass *charClass) print() {
 	}
 }
 
-func (cclass *charClass) addRange(a, b int) {
+func (cclass *charClass) addRange(a, b rune) {
 	// range is a through b inclusive
 	cclass.ranges = append(cclass.ranges, a, b)
 	if a < cclass.cmin {
@@ -203,7 +203,7 @@ func (cclass *charClass) addRange(a, b int) {
 	}
 }
 
-func (cclass *charClass) matches(c int) bool {
+func (cclass *charClass) matches(c rune) bool {
 	if c < cclass.cmin || c > cclass.cmax {
 		return cclass.negate
 	}
@@ -219,7 +219,7 @@ func (cclass *charClass) matches(c int) bool {
 func newCharClass() *instr {
 	i := &instr{kind: iCharClass}
 	i.cclass = new(charClass)
-	i.cclass.ranges = make([]int, 0, 4)
+	i.cclass.ranges = make([]rune, 0, 4)
 	i.cclass.cmin = 0x10FFFF + 1 // MaxRune + 1
 	i.cclass.cmax = -1
 	return i
@@ -235,7 +235,7 @@ type parser struct {
 	re    *Regexp
 	nlpar int // number of unclosed lpars
 	pos   int
-	ch    int
+	ch    rune
 }
 
 func (p *parser) error(err Error) {
@@ -244,9 +244,9 @@ func (p *parser) error(err Error) {
 
 const endOfText = -1
 
-func (p *parser) c() int { return p.ch }
+func (p *parser) c() rune { return p.ch }
 
-func (p *parser) nextc() int {
+func (p *parser) nextc() rune {
 	if p.pos >= len(p.re.expr) {
 		p.ch = endOfText
 	} else {
@@ -264,7 +264,7 @@ func newParser(re *Regexp) *parser {
 	return p
 }
 
-func special(c int) bool {
+func special(c rune) bool {
 	for _, r := range `\.+*?()|[]^$` {
 		if c == r {
 			return true
@@ -273,7 +273,7 @@ func special(c int) bool {
 	return false
 }
 
-func ispunct(c int) bool {
+func ispunct(c rune) bool {
 	for _, r := range "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~" {
 		if c == r {
 			return true
@@ -285,16 +285,16 @@ func ispunct(c int) bool {
 var escapes = []byte("abfnrtv")
 var escaped = []byte("\a\b\f\n\r\t\v")
 
-func escape(c int) int {
+func escape(c rune) int {
 	for i, b := range escapes {
-		if int(b) == c {
+		if rune(b) == c {
 			return i
 		}
 	}
 	return -1
 }
 
-func (p *parser) checkBackslash() int {
+func (p *parser) checkBackslash() rune {
 	c := p.c()
 	if c == '\\' {
 		c = p.nextc()
@@ -304,7 +304,7 @@ func (p *parser) checkBackslash() int {
 		case ispunct(c):
 			// c is as delivered
 		case escape(c) >= 0:
-			c = int(escaped[escape(c)])
+			c = rune(escaped[escape(c)])
 		default:
 			p.error(ErrBadBackslash)
 		}
@@ -319,7 +319,7 @@ func (p *parser) charClass() *instr {
 		cc.negate = true
 		p.nextc()
 	}
-	left := -1
+	left := rune(-1)
 	for {
 		switch c := p.c(); c {
 		case ']', endOfText:
@@ -751,8 +751,8 @@ func (a *matchArena) addState(s []state, inst *instr, prefixed bool, match *matc
 // input abstracts different representations of the input text. It provides
 // one-character lookahead.
 type input interface {
-	step(pos int) (rune int, width int) // advance one rune
-	canCheckPrefix() bool               // can we look ahead without losing info?
+	step(pos int) (r rune, width int) // advance one rune
+	canCheckPrefix() bool             // can we look ahead without losing info?
 	hasPrefix(re *Regexp) bool
 	index(re *Regexp, pos int) int
 }
@@ -766,7 +766,7 @@ func newInputString(str string) *inputString {
 	return &inputString{str: str}
 }
 
-func (i *inputString) step(pos int) (int, int) {
+func (i *inputString) step(pos int) (rune, int) {
 	if pos < len(i.str) {
 		return utf8.DecodeRuneInString(i.str[pos:len(i.str)])
 	}
@@ -794,7 +794,7 @@ func newInputBytes(str []byte) *inputBytes {
 	return &inputBytes{str: str}
 }
 
-func (i *inputBytes) step(pos int) (int, int) {
+func (i *inputBytes) step(pos int) (rune, int) {
 	if pos < len(i.str) {
 		return utf8.DecodeRune(i.str[pos:len(i.str)])
 	}
@@ -824,7 +824,7 @@ func newInputReader(r io.RuneReader) *inputReader {
 	return &inputReader{r: r}
 }
 
-func (i *inputReader) step(pos int) (int, int) {
+func (i *inputReader) step(pos int) (rune, int) {
 	if !i.atEOT && pos != i.pos {
 		return endOfText, 0
 
@@ -886,7 +886,7 @@ func (re *Regexp) doExecute(i input, pos int) []int {
 		atBOT: pos == 0,
 		atEOT: nextChar == endOfText,
 	}
-	for c, startPos := 0, pos; c != endOfText; {
+	for c, startPos := rune(0), pos; c != endOfText; {
 		if !found && (pos == startPos || !anchored) {
 			// prime the pump if we haven't seen a match yet
 			match := arena.noMatch()
@@ -966,7 +966,7 @@ func (re *Regexp) doExecute(i input, pos int) []int {
 // of the regular expression re.  It returns the boolean true if the
 // literal string comprises the entire regular expression.
 func (re *Regexp) LiteralPrefix() (prefix string, complete bool) {
-	c := make([]int, len(re.inst)-2) // minus start and end.
+	c := make([]rune, len(re.inst)-2) // minus start and end.
 	// First instruction is start; skip that.
 	i := 0
 	for inst := re.inst[0].next; inst.kind != iEnd; inst = inst.next {
@@ -1141,7 +1141,7 @@ func QuoteMeta(s string) string {
 	// A byte loop is correct because all metacharacters are ASCII.
 	j := 0
 	for i := 0; i < len(s); i++ {
-		if special(int(s[i])) {
+		if special(rune(s[i])) {
 			b[j] = '\\'
 			j++
 		}
diff --git a/libgo/go/old/template/parse.go b/libgo/go/old/template/parse.go
index dedf9ad..9f8d1eb 100644
--- a/libgo/go/old/template/parse.go
+++ b/libgo/go/old/template/parse.go
@@ -146,8 +146,8 @@ func (t *Template) parseError(err string, args ...interface{}) {
 
 // Is this an exported - upper case - name?
 func isExported(name string) bool {
-	rune, _ := utf8.DecodeRuneInString(name)
-	return unicode.IsUpper(rune)
+	r, _ := utf8.DecodeRuneInString(name)
+	return unicode.IsUpper(r)
 }
 
 // -- Lexical analysis
@@ -419,7 +419,7 @@ func (t *Template) newVariable(words []string) *variableElement {
 		case '"', '`', '\'':
 			v, err := strconv.Unquote(word)
 			if err == nil && word[0] == '\'' {
-				args[i] = []int(v)[0]
+				args[i], _ = utf8.DecodeRuneInString(v)
 			} else {
 				args[i], lerr = v, err
 			}
diff --git a/libgo/go/os/file.go b/libgo/go/os/file.go
index 4335d45..9f982e1 100644
--- a/libgo/go/os/file.go
+++ b/libgo/go/os/file.go
@@ -69,7 +69,7 @@ func (file *File) Read(b []byte) (n int, err Error) {
 	if n < 0 {
 		n = 0
 	}
-	if n == 0 && !iserror(e) {
+	if n == 0 && len(b) > 0 && !iserror(e) {
 		return 0, EOF
 	}
 	if iserror(e) {
diff --git a/libgo/go/os/os_test.go b/libgo/go/os/os_test.go
index 3277fc2..b8c4967 100644
--- a/libgo/go/os/os_test.go
+++ b/libgo/go/os/os_test.go
@@ -163,6 +163,27 @@ func TestLstat(t *testing.T) {
 	}
 }
 
+// Read with length 0 should not return EOF.
+func TestRead0(t *testing.T) {
+	path := sfdir + "/" + sfname
+	f, err := Open(path)
+	if err != nil {
+		t.Fatal("open failed:", err)
+	}
+	defer f.Close()
+
+	b := make([]byte, 0)
+	n, err := f.Read(b)
+	if n != 0 || err != nil {
+		t.Errorf("Read(0) = %d, %v, want 0, nil", n, err)
+	}
+	b = make([]byte, 100)
+	n, err = f.Read(b)
+	if n <= 0 || err != nil {
+		t.Errorf("Read(100) = %d, %v, want >0, nil", n, err)
+	}
+}
+
 func testReaddirnames(dir string, contents []string, t *testing.T) {
 	file, err := Open(dir)
 	defer file.Close()
diff --git a/libgo/go/path/filepath/match.go b/libgo/go/path/filepath/match.go
index 0ccc87e..15c84a7 100644
--- a/libgo/go/path/filepath/match.go
+++ b/libgo/go/path/filepath/match.go
@@ -136,7 +136,7 @@ func matchChunk(chunk, s string) (rest string, ok bool, err os.Error) {
 					chunk = chunk[1:]
 					break
 				}
-				var lo, hi int
+				var lo, hi rune
 				if lo, chunk, err = getEsc(chunk); err != nil {
 					return
 				}
@@ -183,7 +183,7 @@ func matchChunk(chunk, s string) (rest string, ok bool, err os.Error) {
 }
 
 // getEsc gets a possibly-escaped character from chunk, for a character class.
-func getEsc(chunk string) (r int, nchunk string, err os.Error) {
+func getEsc(chunk string) (r rune, nchunk string, err os.Error) {
 	if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
 		err = ErrBadPattern
 		return
diff --git a/libgo/go/path/match.go b/libgo/go/path/match.go
index efb8c5c..e9d0327 100644
--- a/libgo/go/path/match.go
+++ b/libgo/go/path/match.go
@@ -136,7 +136,7 @@ func matchChunk(chunk, s string) (rest string, ok bool, err os.Error) {
 					chunk = chunk[1:]
 					break
 				}
-				var lo, hi int
+				var lo, hi rune
 				if lo, chunk, err = getEsc(chunk); err != nil {
 					return
 				}
@@ -183,7 +183,7 @@ func matchChunk(chunk, s string) (rest string, ok bool, err os.Error) {
 }
 
 // getEsc gets a possibly-escaped character from chunk, for a character class.
-func getEsc(chunk string) (r int, nchunk string, err os.Error) {
+func getEsc(chunk string) (r rune, nchunk string, err os.Error) {
 	if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
 		err = ErrBadPattern
 		return
diff --git a/libgo/go/reflect/all_test.go b/libgo/go/reflect/all_test.go
index 696bd56..98b6e23 100644
--- a/libgo/go/reflect/all_test.go
+++ b/libgo/go/reflect/all_test.go
@@ -11,7 +11,7 @@ import (
 	"io"
 	"os"
 	. "reflect"
-/*	"runtime" */
+	/*	"runtime" */
 	"testing"
 	"unsafe"
 )
@@ -434,7 +434,7 @@ func TestInterfaceGet(t *testing.T) {
 	inter.E = 123.456
 	v1 := ValueOf(&inter)
 	v2 := v1.Elem().Field(0)
-	assert(t, v2.Type().String(), "interface { }")
+	assert(t, v2.Type().String(), "interface {}")
 	i2 := v2.Interface()
 	v3 := ValueOf(i2)
 	assert(t, v3.Type().String(), "float64")
@@ -447,7 +447,7 @@ func TestInterfaceValue(t *testing.T) {
 	inter.E = 123.456
 	v1 := ValueOf(&inter)
 	v2 := v1.Elem().Field(0)
-	assert(t, v2.Type().String(), "interface { }")
+	assert(t, v2.Type().String(), "interface {}")
 	v3 := v2.Elem()
 	assert(t, v3.Type().String(), "float64")
 
diff --git a/libgo/go/regexp/exec.go b/libgo/go/regexp/exec.go
index 3b0e388..d7057a1 100644
--- a/libgo/go/regexp/exec.go
+++ b/libgo/go/regexp/exec.go
@@ -90,15 +90,15 @@ func (m *machine) match(i input, pos int) bool {
 		m.matchcap[i] = -1
 	}
 	runq, nextq := &m.q0, &m.q1
-	rune, rune1 := endOfText, endOfText
+	r, r1 := endOfText, endOfText
 	width, width1 := 0, 0
-	rune, width = i.step(pos)
-	if rune != endOfText {
-		rune1, width1 = i.step(pos + width)
+	r, width = i.step(pos)
+	if r != endOfText {
+		r1, width1 = i.step(pos + width)
 	}
 	var flag syntax.EmptyOp
 	if pos == 0 {
-		flag = syntax.EmptyOpContext(-1, rune)
+		flag = syntax.EmptyOpContext(-1, r)
 	} else {
 		flag = i.context(pos)
 	}
@@ -112,15 +112,15 @@ func (m *machine) match(i input, pos int) bool {
 				// Have match; finished exploring alternatives.
 				break
 			}
-			if len(m.re.prefix) > 0 && rune1 != m.re.prefixRune && i.canCheckPrefix() {
+			if len(m.re.prefix) > 0 && r1 != m.re.prefixRune && i.canCheckPrefix() {
 				// Match requires literal prefix; fast search for it.
 				advance := i.index(m.re, pos)
 				if advance < 0 {
 					break
 				}
 				pos += advance
-				rune, width = i.step(pos)
-				rune1, width1 = i.step(pos + width)
+				r, width = i.step(pos)
+				r1, width1 = i.step(pos + width)
 			}
 		}
 		if !m.matched {
@@ -129,8 +129,8 @@ func (m *machine) match(i input, pos int) bool {
 			}
 			m.add(runq, uint32(m.p.Start), pos, m.matchcap, flag, nil)
 		}
-		flag = syntax.EmptyOpContext(rune, rune1)
-		m.step(runq, nextq, pos, pos+width, rune, flag)
+		flag = syntax.EmptyOpContext(r, r1)
+		m.step(runq, nextq, pos, pos+width, r, flag)
 		if width == 0 {
 			break
 		}
@@ -140,9 +140,9 @@ func (m *machine) match(i input, pos int) bool {
 			break
 		}
 		pos += width
-		rune, width = rune1, width1
-		if rune != endOfText {
-			rune1, width1 = i.step(pos + width)
+		r, width = r1, width1
+		if r != endOfText {
+			r1, width1 = i.step(pos + width)
 		}
 		runq, nextq = nextq, runq
 	}
@@ -166,7 +166,7 @@ func (m *machine) clear(q *queue) {
 // The step processes the rune c (which may be endOfText),
 // which starts at position pos and ends at nextPos.
 // nextCond gives the setting for the empty-width flags after c.
-func (m *machine) step(runq, nextq *queue, pos, nextPos, c int, nextCond syntax.EmptyOp) {
+func (m *machine) step(runq, nextq *queue, pos, nextPos int, c rune, nextCond syntax.EmptyOp) {
 	longest := m.re.longest
 	for j := 0; j < len(runq.dense); j++ {
 		d := &runq.dense[j]
diff --git a/libgo/go/regexp/regexp.go b/libgo/go/regexp/regexp.go
index 2325f62..a1b7951 100644
--- a/libgo/go/regexp/regexp.go
+++ b/libgo/go/regexp/regexp.go
@@ -83,7 +83,7 @@ type Regexp struct {
 	prefix         string         // required prefix in unanchored matches
 	prefixBytes    []byte         // prefix, as a []byte
 	prefixComplete bool           // prefix is the entire regexp
-	prefixRune     int            // first rune in prefix
+	prefixRune     rune           // first rune in prefix
 	cond           syntax.EmptyOp // empty-width conditions required at start of match
 	numSubexp      int
 	longest        bool
@@ -224,13 +224,13 @@ func (re *Regexp) NumSubexp() int {
 	return re.numSubexp
 }
 
-const endOfText = -1
+const endOfText rune = -1
 
 // input abstracts different representations of the input text. It provides
 // one-character lookahead.
 type input interface {
-	step(pos int) (rune int, width int) // advance one rune
-	canCheckPrefix() bool               // can we look ahead without losing info?
+	step(pos int) (r rune, width int) // advance one rune
+	canCheckPrefix() bool             // can we look ahead without losing info?
 	hasPrefix(re *Regexp) bool
 	index(re *Regexp, pos int) int
 	context(pos int) syntax.EmptyOp
@@ -245,11 +245,11 @@ func newInputString(str string) *inputString {
 	return &inputString{str: str}
 }
 
-func (i *inputString) step(pos int) (int, int) {
+func (i *inputString) step(pos int) (rune, int) {
 	if pos < len(i.str) {
 		c := i.str[pos]
 		if c < utf8.RuneSelf {
-			return int(c), 1
+			return rune(c), 1
 		}
 		return utf8.DecodeRuneInString(i.str[pos:])
 	}
@@ -269,7 +269,7 @@ func (i *inputString) index(re *Regexp, pos int) int {
 }
 
 func (i *inputString) context(pos int) syntax.EmptyOp {
-	r1, r2 := -1, -1
+	r1, r2 := endOfText, endOfText
 	if pos > 0 && pos <= len(i.str) {
 		r1, _ = utf8.DecodeLastRuneInString(i.str[:pos])
 	}
@@ -288,11 +288,11 @@ func newInputBytes(str []byte) *inputBytes {
 	return &inputBytes{str: str}
 }
 
-func (i *inputBytes) step(pos int) (int, int) {
+func (i *inputBytes) step(pos int) (rune, int) {
 	if pos < len(i.str) {
 		c := i.str[pos]
 		if c < utf8.RuneSelf {
-			return int(c), 1
+			return rune(c), 1
 		}
 		return utf8.DecodeRune(i.str[pos:])
 	}
@@ -312,7 +312,7 @@ func (i *inputBytes) index(re *Regexp, pos int) int {
 }
 
 func (i *inputBytes) context(pos int) syntax.EmptyOp {
-	r1, r2 := -1, -1
+	r1, r2 := endOfText, endOfText
 	if pos > 0 && pos <= len(i.str) {
 		r1, _ = utf8.DecodeLastRune(i.str[:pos])
 	}
@@ -333,7 +333,7 @@ func newInputReader(r io.RuneReader) *inputReader {
 	return &inputReader{r: r}
 }
 
-func (i *inputReader) step(pos int) (int, int) {
+func (i *inputReader) step(pos int) (rune, int) {
 	if !i.atEOT && pos != i.pos {
 		return endOfText, 0
 
diff --git a/libgo/go/regexp/syntax/compile.go b/libgo/go/regexp/syntax/compile.go
index c415d39..c90de3f 100644
--- a/libgo/go/regexp/syntax/compile.go
+++ b/libgo/go/regexp/syntax/compile.go
@@ -91,8 +91,8 @@ func (c *compiler) init() {
 	c.inst(InstFail)
 }
 
-var anyRuneNotNL = []int{0, '\n' - 1, '\n' + 1, unicode.MaxRune}
-var anyRune = []int{0, unicode.MaxRune}
+var anyRuneNotNL = []rune{0, '\n' - 1, '\n' + 1, unicode.MaxRune}
+var anyRune = []rune{0, unicode.MaxRune}
 
 func (c *compiler) compile(re *Regexp) frag {
 	switch re.Op {
@@ -262,12 +262,12 @@ func (c *compiler) empty(op EmptyOp) frag {
 	return f
 }
 
-func (c *compiler) rune(rune []int, flags Flags) frag {
+func (c *compiler) rune(r []rune, flags Flags) frag {
 	f := c.inst(InstRune)
 	i := &c.p.Inst[f.i]
-	i.Rune = rune
+	i.Rune = r
 	flags &= FoldCase // only relevant flag is FoldCase
-	if len(rune) != 1 || unicode.SimpleFold(rune[0]) == rune[0] {
+	if len(r) != 1 || unicode.SimpleFold(r[0]) == r[0] {
 		// and sometimes not even that
 		flags &^= FoldCase
 	}
@@ -276,11 +276,11 @@ func (c *compiler) rune(rune []int, flags Flags) frag {
 
 	// Special cases for exec machine.
 	switch {
-	case flags&FoldCase == 0 && (len(rune) == 1 || len(rune) == 2 && rune[0] == rune[1]):
+	case flags&FoldCase == 0 && (len(r) == 1 || len(r) == 2 && r[0] == r[1]):
 		i.Op = InstRune1
-	case len(rune) == 2 && rune[0] == 0 && rune[1] == unicode.MaxRune:
+	case len(r) == 2 && r[0] == 0 && r[1] == unicode.MaxRune:
 		i.Op = InstRuneAny
-	case len(rune) == 4 && rune[0] == 0 && rune[1] == '\n'-1 && rune[2] == '\n'+1 && rune[3] == unicode.MaxRune:
+	case len(r) == 4 && r[0] == 0 && r[1] == '\n'-1 && r[2] == '\n'+1 && r[3] == unicode.MaxRune:
 		i.Op = InstRuneAnyNotNL
 	}
 
diff --git a/libgo/go/regexp/syntax/parse.go b/libgo/go/regexp/syntax/parse.go
index 7013459..bb19c5a 100644
--- a/libgo/go/regexp/syntax/parse.go
+++ b/libgo/go/regexp/syntax/parse.go
@@ -82,7 +82,7 @@ type parser struct {
 	free        *Regexp
 	numCap      int // number of capturing groups seen
 	wholeRegexp string
-	tmpClass    []int // temporary char class work space
+	tmpClass    []rune // temporary char class work space
 }
 
 func (p *parser) newRegexp(op Op) *Regexp {
@@ -149,7 +149,7 @@ func (p *parser) push(re *Regexp) *Regexp {
 // If r >= 0 and there's a node left over, maybeConcat uses it
 // to push r with the given flags.
 // maybeConcat reports whether r was pushed.
-func (p *parser) maybeConcat(r int, flags Flags) bool {
+func (p *parser) maybeConcat(r rune, flags Flags) bool {
 	n := len(p.stack)
 	if n < 2 {
 		return false
@@ -178,7 +178,7 @@ func (p *parser) maybeConcat(r int, flags Flags) bool {
 }
 
 // newLiteral returns a new OpLiteral Regexp with the given flags
-func (p *parser) newLiteral(r int, flags Flags) *Regexp {
+func (p *parser) newLiteral(r rune, flags Flags) *Regexp {
 	re := p.newRegexp(OpLiteral)
 	re.Flags = flags
 	if flags&FoldCase != 0 {
@@ -190,7 +190,7 @@ func (p *parser) newLiteral(r int, flags Flags) *Regexp {
 }
 
 // minFoldRune returns the minimum rune fold-equivalent to r.
-func minFoldRune(r int) int {
+func minFoldRune(r rune) rune {
 	if r < MinFold || r > MaxFold {
 		return r
 	}
@@ -206,7 +206,7 @@ func minFoldRune(r int) int {
 
 // literal pushes a literal regexp for the rune r on the stack
 // and returns that regexp.
-func (p *parser) literal(r int) {
+func (p *parser) literal(r rune) {
 	p.push(p.newLiteral(r, p.flags))
 }
 
@@ -369,7 +369,7 @@ func (p *parser) factor(sub []*Regexp, flags Flags) []*Regexp {
 	}
 
 	// Round 1: Factor out common literal prefixes.
-	var str []int
+	var str []rune
 	var strflags Flags
 	start := 0
 	out := sub[:0]
@@ -380,7 +380,7 @@ func (p *parser) factor(sub []*Regexp, flags Flags) []*Regexp {
 		//
 		// Invariant: sub[start:i] consists of regexps that all begin
 		// with str as modified by strflags.
-		var istr []int
+		var istr []rune
 		var iflags Flags
 		if i < len(sub) {
 			istr, iflags = p.leadingString(sub[i])
@@ -543,7 +543,7 @@ func (p *parser) factor(sub []*Regexp, flags Flags) []*Regexp {
 
 // leadingString returns the leading literal string that re begins with.
 // The string refers to storage in re or its children.
-func (p *parser) leadingString(re *Regexp) ([]int, Flags) {
+func (p *parser) leadingString(re *Regexp) ([]rune, Flags) {
 	if re.Op == OpConcat && len(re.Sub) > 0 {
 		re = re.Sub[0]
 	}
@@ -639,7 +639,7 @@ func literalRegexp(s string, flags Flags) *Regexp {
 	for _, c := range s {
 		if len(re.Rune) >= cap(re.Rune) {
 			// string is too long to fit in Rune0.  let Go handle it
-			re.Rune = []int(s)
+			re.Rune = []rune(s)
 			break
 		}
 		re.Rune = append(re.Rune, c)
@@ -662,7 +662,7 @@ func Parse(s string, flags Flags) (*Regexp, os.Error) {
 	var (
 		p          parser
 		err        os.Error
-		c          int
+		c          rune
 		op         Op
 		lastRepeat string
 		min, max   int
@@ -935,7 +935,7 @@ func (p *parser) parsePerlFlags(s string) (rest string, err os.Error) {
 	}
 
 	// Non-capturing group.  Might also twiddle Perl flags.
-	var c int
+	var c rune
 	t = t[2:] // skip (?
 	flags := p.flags
 	sign := +1
@@ -1049,7 +1049,7 @@ func isCharClass(re *Regexp) bool {
 }
 
 // does re match r?
-func matchRune(re *Regexp, r int) bool {
+func matchRune(re *Regexp, r rune) bool {
 	switch re.Op {
 	case OpLiteral:
 		return len(re.Rune) == 1 && re.Rune[0] == r
@@ -1186,7 +1186,7 @@ func (p *parser) parseRightParen() os.Error {
 
 // parseEscape parses an escape sequence at the beginning of s
 // and returns the rune.
-func (p *parser) parseEscape(s string) (r int, rest string, err os.Error) {
+func (p *parser) parseEscape(s string) (r rune, rest string, err os.Error) {
 	t := s[1:]
 	if t == "" {
 		return 0, "", &Error{ErrTrailingBackslash, ""}
@@ -1221,7 +1221,7 @@ Switch:
 			if t == "" || t[0] < '0' || t[0] > '7' {
 				break
 			}
-			r = r*8 + int(t[0]) - '0'
+			r = r*8 + rune(t[0]) - '0'
 			t = t[1:]
 		}
 		return r, t, nil
@@ -1302,7 +1302,7 @@ Switch:
 
 // parseClassChar parses a character class character at the beginning of s
 // and returns it.
-func (p *parser) parseClassChar(s, wholeClass string) (r int, rest string, err os.Error) {
+func (p *parser) parseClassChar(s, wholeClass string) (r rune, rest string, err os.Error) {
 	if s == "" {
 		return 0, "", &Error{Code: ErrMissingBracket, Expr: wholeClass}
 	}
@@ -1318,13 +1318,13 @@ func (p *parser) parseClassChar(s, wholeClass string) (r int, rest string, err o
 
 type charGroup struct {
 	sign  int
-	class []int
+	class []rune
 }
 
 // parsePerlClassEscape parses a leading Perl character class escape like \d
 // from the beginning of s.  If one is present, it appends the characters to r
 // and returns the new slice r and the remainder of the string.
-func (p *parser) parsePerlClassEscape(s string, r []int) (out []int, rest string) {
+func (p *parser) parsePerlClassEscape(s string, r []rune) (out []rune, rest string) {
 	if p.flags&PerlX == 0 || len(s) < 2 || s[0] != '\\' {
 		return
 	}
@@ -1338,7 +1338,7 @@ func (p *parser) parsePerlClassEscape(s string, r []int) (out []int, rest string
 // parseNamedClass parses a leading POSIX named character class like [:alnum:]
 // from the beginning of s.  If one is present, it appends the characters to r
 // and returns the new slice r and the remainder of the string.
-func (p *parser) parseNamedClass(s string, r []int) (out []int, rest string, err os.Error) {
+func (p *parser) parseNamedClass(s string, r []rune) (out []rune, rest string, err os.Error) {
 	if len(s) < 2 || s[0] != '[' || s[1] != ':' {
 		return
 	}
@@ -1356,7 +1356,7 @@ func (p *parser) parseNamedClass(s string, r []int) (out []int, rest string, err
 	return p.appendGroup(r, g), s, nil
 }
 
-func (p *parser) appendGroup(r []int, g charGroup) []int {
+func (p *parser) appendGroup(r []rune, g charGroup) []rune {
 	if p.flags&FoldCase == 0 {
 		if g.sign < 0 {
 			r = appendNegatedClass(r, g.class)
@@ -1401,7 +1401,7 @@ func unicodeTable(name string) (*unicode.RangeTable, *unicode.RangeTable) {
 // parseUnicodeClass parses a leading Unicode character class like \p{Han}
 // from the beginning of s.  If one is present, it appends the characters to r
 // and returns the new slice r and the remainder of the string.
-func (p *parser) parseUnicodeClass(s string, r []int) (out []int, rest string, err os.Error) {
+func (p *parser) parseUnicodeClass(s string, r []rune) (out []rune, rest string, err os.Error) {
 	if p.flags&UnicodeGroups == 0 || len(s) < 2 || s[0] != '\\' || s[1] != 'p' && s[1] != 'P' {
 		return
 	}
@@ -1533,7 +1533,7 @@ func (p *parser) parseClass(s string) (rest string, err os.Error) {
 
 		// Single character or simple range.
 		rng := t
-		var lo, hi int
+		var lo, hi rune
 		if lo, t, err = p.parseClassChar(t, s); err != nil {
 			return "", err
 		}
@@ -1570,7 +1570,7 @@ func (p *parser) parseClass(s string) (rest string, err os.Error) {
 
 // cleanClass sorts the ranges (pairs of elements of r),
 // merges them, and eliminates duplicates.
-func cleanClass(rp *[]int) []int {
+func cleanClass(rp *[]rune) []rune {
 
 	// Sort by lo increasing, hi decreasing to break ties.
 	sort.Sort(ranges{rp})
@@ -1601,15 +1601,15 @@ func cleanClass(rp *[]int) []int {
 }
 
 // appendLiteral returns the result of appending the literal x to the class r.
-func appendLiteral(r []int, x int, flags Flags) []int {
+func appendLiteral(r []rune, x rune, flags Flags) []rune {
 	if flags&FoldCase != 0 {
 		return appendFoldedRange(r, x, x)
 	}
 	return AppendRange(r, x, x)
 }
 
-// AppendRange returns the result of appending the range lo-hi to the class r.
-func AppendRange(r []int, lo, hi int) []int {
+// appendRange returns the result of appending the range lo-hi to the class r.
+func AppendRange(r []rune, lo, hi rune) []rune {
 	// Expand last range or next to last range if it overlaps or abuts.
 	// Checking two ranges helps when appending case-folded
 	// alphabets, so that one range can be expanding A-Z and the
@@ -1642,7 +1642,7 @@ const (
 
 // appendFoldedRange returns the result of appending the range lo-hi
 // and its case folding-equivalent runes to the class r.
-func appendFoldedRange(r []int, lo, hi int) []int {
+func appendFoldedRange(r []rune, lo, hi rune) []rune {
 	// Optimizations.
 	if lo <= MinFold && hi >= MaxFold {
 		// Range is full: folding can't add more.
@@ -1677,7 +1677,7 @@ func appendFoldedRange(r []int, lo, hi int) []int {
 
 // appendClass returns the result of appending the class x to the class r.
 // It assume x is clean.
-func appendClass(r []int, x []int) []int {
+func appendClass(r []rune, x []rune) []rune {
 	for i := 0; i < len(x); i += 2 {
 		r = AppendRange(r, x[i], x[i+1])
 	}
@@ -1685,7 +1685,7 @@ func appendClass(r []int, x []int) []int {
 }
 
 // appendFolded returns the result of appending the case folding of the class x to the class r.
-func appendFoldedClass(r []int, x []int) []int {
+func appendFoldedClass(r []rune, x []rune) []rune {
 	for i := 0; i < len(x); i += 2 {
 		r = appendFoldedRange(r, x[i], x[i+1])
 	}
@@ -1694,8 +1694,8 @@ func appendFoldedClass(r []int, x []int) []int {
 
 // appendNegatedClass returns the result of appending the negation of the class x to the class r.
 // It assumes x is clean.
-func appendNegatedClass(r []int, x []int) []int {
-	nextLo := 0
+func appendNegatedClass(r []rune, x []rune) []rune {
+	nextLo := rune('\u0000')
 	for i := 0; i < len(x); i += 2 {
 		lo, hi := x[i], x[i+1]
 		if nextLo <= lo-1 {
@@ -1710,9 +1710,9 @@ func appendNegatedClass(r []int, x []int) []int {
 }
 
 // appendTable returns the result of appending x to the class r.
-func appendTable(r []int, x *unicode.RangeTable) []int {
+func appendTable(r []rune, x *unicode.RangeTable) []rune {
 	for _, xr := range x.R16 {
-		lo, hi, stride := int(xr.Lo), int(xr.Hi), int(xr.Stride)
+		lo, hi, stride := rune(xr.Lo), rune(xr.Hi), rune(xr.Stride)
 		if stride == 1 {
 			r = AppendRange(r, lo, hi)
 			continue
@@ -1722,7 +1722,7 @@ func appendTable(r []int, x *unicode.RangeTable) []int {
 		}
 	}
 	for _, xr := range x.R32 {
-		lo, hi, stride := int(xr.Lo), int(xr.Hi), int(xr.Stride)
+		lo, hi, stride := rune(xr.Lo), rune(xr.Hi), rune(xr.Stride)
 		if stride == 1 {
 			r = AppendRange(r, lo, hi)
 			continue
@@ -1735,10 +1735,10 @@ func appendTable(r []int, x *unicode.RangeTable) []int {
 }
 
 // appendNegatedTable returns the result of appending the negation of x to the class r.
-func appendNegatedTable(r []int, x *unicode.RangeTable) []int {
-	nextLo := 0 // lo end of next class to add
+func appendNegatedTable(r []rune, x *unicode.RangeTable) []rune {
+	nextLo := rune('\u0000') // lo end of next class to add
 	for _, xr := range x.R16 {
-		lo, hi, stride := int(xr.Lo), int(xr.Hi), int(xr.Stride)
+		lo, hi, stride := rune(xr.Lo), rune(xr.Hi), rune(xr.Stride)
 		if stride == 1 {
 			if nextLo <= lo-1 {
 				r = AppendRange(r, nextLo, lo-1)
@@ -1754,7 +1754,7 @@ func appendNegatedTable(r []int, x *unicode.RangeTable) []int {
 		}
 	}
 	for _, xr := range x.R32 {
-		lo, hi, stride := int(xr.Lo), int(xr.Hi), int(xr.Stride)
+		lo, hi, stride := rune(xr.Lo), rune(xr.Hi), rune(xr.Stride)
 		if stride == 1 {
 			if nextLo <= lo-1 {
 				r = AppendRange(r, nextLo, lo-1)
@@ -1777,9 +1777,9 @@ func appendNegatedTable(r []int, x *unicode.RangeTable) []int {
 
 // negateClass overwrites r and returns r's negation.
 // It assumes the class r is already clean.
-func negateClass(r []int) []int {
-	nextLo := 0 // lo end of next class to add
-	w := 0      // write index
+func negateClass(r []rune) []rune {
+	nextLo := rune('\u0000') // lo end of next class to add
+	w := 0                   // write index
 	for i := 0; i < len(r); i += 2 {
 		lo, hi := r[i], r[i+1]
 		if nextLo <= lo-1 {
@@ -1801,9 +1801,9 @@ func negateClass(r []int) []int {
 // ranges implements sort.Interface on a []rune.
 // The choice of receiver type definition is strange
 // but avoids an allocation since we already have
-// a *[]int.
+// a *[]rune.
 type ranges struct {
-	p *[]int
+	p *[]rune
 }
 
 func (ra ranges) Less(i, j int) bool {
@@ -1835,7 +1835,7 @@ func checkUTF8(s string) os.Error {
 	return nil
 }
 
-func nextRune(s string) (c int, t string, err os.Error) {
+func nextRune(s string) (c rune, t string, err os.Error) {
 	c, size := utf8.DecodeRuneInString(s)
 	if c == utf8.RuneError && size == 1 {
 		return 0, "", &Error{Code: ErrInvalidUTF8, Expr: s}
@@ -1843,11 +1843,11 @@ func nextRune(s string) (c int, t string, err os.Error) {
 	return c, s[size:], nil
 }
 
-func isalnum(c int) bool {
+func isalnum(c rune) bool {
 	return '0' <= c && c <= '9' || 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z'
 }
 
-func unhex(c int) int {
+func unhex(c rune) rune {
 	if '0' <= c && c <= '9' {
 		return c - '0'
 	}
diff --git a/libgo/go/regexp/syntax/parse_test.go b/libgo/go/regexp/syntax/parse_test.go
index 5d9085b..88f65ec 100644
--- a/libgo/go/regexp/syntax/parse_test.go
+++ b/libgo/go/regexp/syntax/parse_test.go
@@ -5,9 +5,9 @@
 package syntax_test
 
 import (
-	. "regexp/syntax"
 	"bytes"
 	"fmt"
+	. "regexp/syntax"
 	"testing"
 	"unicode"
 )
@@ -372,10 +372,10 @@ func dumpRegexp(b *bytes.Buffer, re *Regexp) {
 	b.WriteByte('}')
 }
 
-func mkCharClass(f func(int) bool) string {
+func mkCharClass(f func(rune) bool) string {
 	re := &Regexp{Op: OpCharClass}
-	lo := -1
-	for i := 0; i <= unicode.MaxRune; i++ {
+	lo := rune(-1)
+	for i := rune(0); i <= unicode.MaxRune; i++ {
 		if f(i) {
 			if lo < 0 {
 				lo = i
@@ -393,12 +393,12 @@ func mkCharClass(f func(int) bool) string {
 	return dump(re)
 }
 
-func isUpperFold(rune int) bool {
-	if unicode.IsUpper(rune) {
+func isUpperFold(r rune) bool {
+	if unicode.IsUpper(r) {
 		return true
 	}
-	c := unicode.SimpleFold(rune)
-	for c != rune {
+	c := unicode.SimpleFold(r)
+	for c != r {
 		if unicode.IsUpper(c) {
 			return true
 		}
@@ -408,8 +408,8 @@ func isUpperFold(rune int) bool {
 }
 
 func TestFoldConstants(t *testing.T) {
-	last := -1
-	for i := 0; i <= unicode.MaxRune; i++ {
+	last := rune(-1)
+	for i := rune(0); i <= unicode.MaxRune; i++ {
 		if unicode.SimpleFold(i) == i {
 			continue
 		}
@@ -428,8 +428,8 @@ func TestAppendRangeCollapse(t *testing.T) {
 	// into the earlier ones (it looks back two ranges), so that
 	// the slice never grows very large.
 	// Note that we are not calling cleanClass.
-	var r []int
-	for i := 'A'; i <= 'Z'; i++ {
+	var r []rune
+	for i := rune('A'); i <= 'Z'; i++ {
 		r = AppendRange(r, i, i)
 		r = AppendRange(r, i+'a'-'A', i+'a'-'A')
 	}
diff --git a/libgo/go/regexp/syntax/perl_groups.go b/libgo/go/regexp/syntax/perl_groups.go
index 05b392c..1a11ca6 100644
--- a/libgo/go/regexp/syntax/perl_groups.go
+++ b/libgo/go/regexp/syntax/perl_groups.go
@@ -3,17 +3,17 @@
 
 package syntax
 
-var code1 = []int{ /* \d */
+var code1 = []rune{ /* \d */
 	0x30, 0x39,
 }
 
-var code2 = []int{ /* \s */
+var code2 = []rune{ /* \s */
 	0x9, 0xa,
 	0xc, 0xd,
 	0x20, 0x20,
 }
 
-var code3 = []int{ /* \w */
+var code3 = []rune{ /* \w */
 	0x30, 0x39,
 	0x41, 0x5a,
 	0x5f, 0x5f,
@@ -28,71 +28,71 @@ var perlGroup = map[string]charGroup{
 	`\w`: {+1, code3},
 	`\W`: {-1, code3},
 }
-var code4 = []int{ /* [:alnum:] */
+var code4 = []rune{ /* [:alnum:] */
 	0x30, 0x39,
 	0x41, 0x5a,
 	0x61, 0x7a,
 }
 
-var code5 = []int{ /* [:alpha:] */
+var code5 = []rune{ /* [:alpha:] */
 	0x41, 0x5a,
 	0x61, 0x7a,
 }
 
-var code6 = []int{ /* [:ascii:] */
+var code6 = []rune{ /* [:ascii:] */
 	0x0, 0x7f,
 }
 
-var code7 = []int{ /* [:blank:] */
+var code7 = []rune{ /* [:blank:] */
 	0x9, 0x9,
 	0x20, 0x20,
 }
 
-var code8 = []int{ /* [:cntrl:] */
+var code8 = []rune{ /* [:cntrl:] */
 	0x0, 0x1f,
 	0x7f, 0x7f,
 }
 
-var code9 = []int{ /* [:digit:] */
+var code9 = []rune{ /* [:digit:] */
 	0x30, 0x39,
 }
 
-var code10 = []int{ /* [:graph:] */
+var code10 = []rune{ /* [:graph:] */
 	0x21, 0x7e,
 }
 
-var code11 = []int{ /* [:lower:] */
+var code11 = []rune{ /* [:lower:] */
 	0x61, 0x7a,
 }
 
-var code12 = []int{ /* [:print:] */
+var code12 = []rune{ /* [:print:] */
 	0x20, 0x7e,
 }
 
-var code13 = []int{ /* [:punct:] */
+var code13 = []rune{ /* [:punct:] */
 	0x21, 0x2f,
 	0x3a, 0x40,
 	0x5b, 0x60,
 	0x7b, 0x7e,
 }
 
-var code14 = []int{ /* [:space:] */
+var code14 = []rune{ /* [:space:] */
 	0x9, 0xd,
 	0x20, 0x20,
 }
 
-var code15 = []int{ /* [:upper:] */
+var code15 = []rune{ /* [:upper:] */
 	0x41, 0x5a,
 }
 
-var code16 = []int{ /* [:word:] */
+var code16 = []rune{ /* [:word:] */
 	0x30, 0x39,
 	0x41, 0x5a,
 	0x5f, 0x5f,
 	0x61, 0x7a,
 }
 
-var code17 = []int{ /* [:xdigit:] */
+var code17 = []rune{ /* [:xdigit:] */
 	0x30, 0x39,
 	0x41, 0x46,
 	0x61, 0x66,
diff --git a/libgo/go/regexp/syntax/prog.go b/libgo/go/regexp/syntax/prog.go
index ced45da..f5b697a 100644
--- a/libgo/go/regexp/syntax/prog.go
+++ b/libgo/go/regexp/syntax/prog.go
@@ -51,7 +51,7 @@ const (
 // at the beginning of the text.
 // Passing r2 == -1 indicates that the position is
 // at the end of the text.
-func EmptyOpContext(r1, r2 int) EmptyOp {
+func EmptyOpContext(r1, r2 rune) EmptyOp {
 	var op EmptyOp
 	if r1 < 0 {
 		op |= EmptyBeginText | EmptyBeginLine
@@ -76,7 +76,7 @@ func EmptyOpContext(r1, r2 int) EmptyOp {
 // IsWordChar reports whether r is consider a ``word character''
 // during the evaluation of the \b and \B zero-width assertions.
 // These assertions are ASCII-only: the word characters are [A-Za-z0-9_].
-func IsWordChar(r int) bool {
+func IsWordChar(r rune) bool {
 	return 'A' <= r && r <= 'Z' || 'a' <= r && r <= 'z' || '0' <= r && r <= '9' || r == '_'
 }
 
@@ -85,7 +85,7 @@ type Inst struct {
 	Op   InstOp
 	Out  uint32 // all but InstMatch, InstFail
 	Arg  uint32 // InstAlt, InstAltMatch, InstCapture, InstEmptyWidth
-	Rune []int
+	Rune []rune
 }
 
 func (p *Prog) String() string {
@@ -161,7 +161,7 @@ Loop:
 
 // MatchRune returns true if the instruction matches (and consumes) r.
 // It should only be called when i.Op == InstRune.
-func (i *Inst) MatchRune(r int) bool {
+func (i *Inst) MatchRune(r rune) bool {
 	rune := i.Rune
 
 	// Special case: single-rune slice is from literal string, not char class.
@@ -210,17 +210,17 @@ func (i *Inst) MatchRune(r int) bool {
 
 // As per re2's Prog::IsWordChar. Determines whether rune is an ASCII word char.
 // Since we act on runes, it would be easy to support Unicode here.
-func wordRune(rune int) bool {
-	return rune == '_' ||
-		('A' <= rune && rune <= 'Z') ||
-		('a' <= rune && rune <= 'z') ||
-		('0' <= rune && rune <= '9')
+func wordRune(r rune) bool {
+	return r == '_' ||
+		('A' <= r && r <= 'Z') ||
+		('a' <= r && r <= 'z') ||
+		('0' <= r && r <= '9')
 }
 
 // MatchEmptyWidth returns true if the instruction matches
 // an empty string between the runes before and after.
 // It should only be called when i.Op == InstEmptyWidth.
-func (i *Inst) MatchEmptyWidth(before int, after int) bool {
+func (i *Inst) MatchEmptyWidth(before rune, after rune) bool {
 	switch EmptyOp(i.Arg) {
 	case EmptyBeginLine:
 		return before == '\n' || before == -1
diff --git a/libgo/go/regexp/syntax/regexp.go b/libgo/go/regexp/syntax/regexp.go
index 033848d..b5ddab1 100644
--- a/libgo/go/regexp/syntax/regexp.go
+++ b/libgo/go/regexp/syntax/regexp.go
@@ -22,8 +22,8 @@ type Regexp struct {
 	Flags    Flags
 	Sub      []*Regexp  // subexpressions, if any
 	Sub0     [1]*Regexp // storage for short Sub
-	Rune     []int      // matched runes, for OpLiteral, OpCharClass
-	Rune0    [2]int     // storage for short Rune
+	Rune     []rune     // matched runes, for OpLiteral, OpCharClass
+	Rune0    [2]rune    // storage for short Rune
 	Min, Max int        // min, max for OpRepeat
 	Cap      int        // capturing index, for OpCapture
 	Name     string     // capturing name, for OpCapture
@@ -252,7 +252,7 @@ func (re *Regexp) String() string {
 
 const meta = `\.+*?()|[]{}^$`
 
-func escape(b *bytes.Buffer, r int, force bool) {
+func escape(b *bytes.Buffer, r rune, force bool) {
 	if unicode.IsPrint(r) {
 		if strings.IndexRune(meta, r) >= 0 || force {
 			b.WriteRune('\\')
@@ -277,7 +277,7 @@ func escape(b *bytes.Buffer, r int, force bool) {
 	default:
 		if r < 0x100 {
 			b.WriteString(`\x`)
-			s := strconv.Itob(r, 16)
+			s := strconv.Itob(int(r), 16)
 			if len(s) == 1 {
 				b.WriteRune('0')
 			}
@@ -285,7 +285,7 @@ func escape(b *bytes.Buffer, r int, force bool) {
 			break
 		}
 		b.WriteString(`\x{`)
-		b.WriteString(strconv.Itob(r, 16))
+		b.WriteString(strconv.Itob(int(r), 16))
 		b.WriteString(`}`)
 	}
 }
diff --git a/libgo/go/rpc/jsonrpc/all_test.go b/libgo/go/rpc/jsonrpc/all_test.go
index c1a9e8e..99253ba 100644
--- a/libgo/go/rpc/jsonrpc/all_test.go
+++ b/libgo/go/rpc/jsonrpc/all_test.go
@@ -6,6 +6,7 @@ package jsonrpc
 
 import (
 	"fmt"
+	"io"
 	"json"
 	"net"
 	"os"
@@ -154,3 +155,67 @@ func TestClient(t *testing.T) {
 		t.Error("Div: expected divide by zero error; got", err)
 	}
 }
+
+func TestMalformedInput(t *testing.T) {
+	cli, srv := net.Pipe()
+	go cli.Write([]byte(`{id:1}`)) // invalid json
+	ServeConn(srv)                 // must return, not loop
+}
+
+func TestUnexpectedError(t *testing.T) {
+	cli, srv := myPipe()
+	go cli.PipeWriter.CloseWithError(os.NewError("unexpected error!")) // reader will get this error
+	ServeConn(srv)                                                     // must return, not loop
+}
+
+// Copied from package net.
+func myPipe() (*pipe, *pipe) {
+	r1, w1 := io.Pipe()
+	r2, w2 := io.Pipe()
+
+	return &pipe{r1, w2}, &pipe{r2, w1}
+}
+
+type pipe struct {
+	*io.PipeReader
+	*io.PipeWriter
+}
+
+type pipeAddr int
+
+func (pipeAddr) Network() string {
+	return "pipe"
+}
+
+func (pipeAddr) String() string {
+	return "pipe"
+}
+
+func (p *pipe) Close() os.Error {
+	err := p.PipeReader.Close()
+	err1 := p.PipeWriter.Close()
+	if err == nil {
+		err = err1
+	}
+	return err
+}
+
+func (p *pipe) LocalAddr() net.Addr {
+	return pipeAddr(0)
+}
+
+func (p *pipe) RemoteAddr() net.Addr {
+	return pipeAddr(0)
+}
+
+func (p *pipe) SetTimeout(nsec int64) os.Error {
+	return os.NewError("net.Pipe does not support timeouts")
+}
+
+func (p *pipe) SetReadTimeout(nsec int64) os.Error {
+	return os.NewError("net.Pipe does not support timeouts")
+}
+
+func (p *pipe) SetWriteTimeout(nsec int64) os.Error {
+	return os.NewError("net.Pipe does not support timeouts")
+}
diff --git a/libgo/go/rpc/server.go b/libgo/go/rpc/server.go
index f037100..71797e2 100644
--- a/libgo/go/rpc/server.go
+++ b/libgo/go/rpc/server.go
@@ -116,8 +116,8 @@ import (
 	"bufio"
 	"gob"
 	"http"
-	"log"
 	"io"
+	"log"
 	"net"
 	"os"
 	"reflect"
@@ -394,12 +394,12 @@ func (server *Server) ServeConn(conn io.ReadWriteCloser) {
 func (server *Server) ServeCodec(codec ServerCodec) {
 	sending := new(sync.Mutex)
 	for {
-		service, mtype, req, argv, replyv, err := server.readRequest(codec)
+		service, mtype, req, argv, replyv, keepReading, err := server.readRequest(codec)
 		if err != nil {
 			if err != os.EOF {
 				log.Println("rpc:", err)
 			}
-			if err == os.EOF || err == io.ErrUnexpectedEOF {
+			if !keepReading {
 				break
 			}
 			// send a response if we actually managed to read a header.
@@ -418,9 +418,9 @@ func (server *Server) ServeCodec(codec ServerCodec) {
 // It does not close the codec upon completion.
 func (server *Server) ServeRequest(codec ServerCodec) os.Error {
 	sending := new(sync.Mutex)
-	service, mtype, req, argv, replyv, err := server.readRequest(codec)
+	service, mtype, req, argv, replyv, keepReading, err := server.readRequest(codec)
 	if err != nil {
-		if err == os.EOF || err == io.ErrUnexpectedEOF {
+		if !keepReading {
 			return err
 		}
 		// send a response if we actually managed to read a header.
@@ -474,10 +474,10 @@ func (server *Server) freeResponse(resp *Response) {
 	server.respLock.Unlock()
 }
 
-func (server *Server) readRequest(codec ServerCodec) (service *service, mtype *methodType, req *Request, argv, replyv reflect.Value, err os.Error) {
-	service, mtype, req, err = server.readRequestHeader(codec)
+func (server *Server) readRequest(codec ServerCodec) (service *service, mtype *methodType, req *Request, argv, replyv reflect.Value, keepReading bool, err os.Error) {
+	service, mtype, req, keepReading, err = server.readRequestHeader(codec)
 	if err != nil {
-		if err == os.EOF || err == io.ErrUnexpectedEOF {
+		if !keepReading {
 			return
 		}
 		// discard body
@@ -505,7 +505,7 @@ func (server *Server) readRequest(codec ServerCodec) (service *service, mtype *m
 	return
 }
 
-func (server *Server) readRequestHeader(codec ServerCodec) (service *service, mtype *methodType, req *Request, err os.Error) {
+func (server *Server) readRequestHeader(codec ServerCodec) (service *service, mtype *methodType, req *Request, keepReading bool, err os.Error) {
 	// Grab the request header.
 	req = server.getRequest()
 	err = codec.ReadRequestHeader(req)
@@ -518,6 +518,10 @@ func (server *Server) readRequestHeader(codec ServerCodec) (service *service, mt
 		return
 	}
 
+	// We read the header successfully.  If we see an error now,
+	// we can still recover and move on to the next request.
+	keepReading = true
+
 	serviceMethod := strings.Split(req.ServiceMethod, ".")
 	if len(serviceMethod) != 2 {
 		err = os.NewError("rpc: service/method request ill-formed: " + req.ServiceMethod)
diff --git a/libgo/go/rpc/server_test.go b/libgo/go/rpc/server_test.go
index 029741b..3e9fe29 100644
--- a/libgo/go/rpc/server_test.go
+++ b/libgo/go/rpc/server_test.go
@@ -311,8 +311,9 @@ func (codec *CodecEmulator) ReadRequestBody(argv interface{}) os.Error {
 func (codec *CodecEmulator) WriteResponse(resp *Response, reply interface{}) os.Error {
 	if resp.Error != "" {
 		codec.err = os.NewError(resp.Error)
+	} else {
+		*codec.reply = *(reply.(*Reply))
 	}
-	*codec.reply = *(reply.(*Reply))
 	return nil
 }
 
diff --git a/libgo/go/runtime/debug.go b/libgo/go/runtime/debug.go
index 6370a57..1243703 100644
--- a/libgo/go/runtime/debug.go
+++ b/libgo/go/runtime/debug.go
@@ -10,7 +10,6 @@ func Breakpoint()
 // LockOSThread wires the calling goroutine to its current operating system thread.
 // Until the calling goroutine exits or calls UnlockOSThread, it will always
 // execute in that thread, and no other goroutine can.
-// LockOSThread cannot be used during init functions.
 func LockOSThread()
 
 // UnlockOSThread unwires the calling goroutine from its fixed operating system thread.
diff --git a/libgo/go/runtime/pprof/pprof.go b/libgo/go/runtime/pprof/pprof.go
index fdeceb4..7022896 100644
--- a/libgo/go/runtime/pprof/pprof.go
+++ b/libgo/go/runtime/pprof/pprof.go
@@ -17,6 +17,9 @@ import (
 	"sync"
 )
 
+// BUG(rsc): CPU profiling is broken on OS X, due to an Apple kernel bug.
+// For details, see http://code.google.com/p/go/source/detail?r=35b716c94225.
+
 // WriteHeapProfile writes a pprof-formatted heap profile to w.
 // If a write to w returns an error, WriteHeapProfile returns that error.
 // Otherwise, WriteHeapProfile returns nil.
diff --git a/libgo/go/scanner/scanner.go b/libgo/go/scanner/scanner.go
index 29e5f8c..3594db9 100644
--- a/libgo/go/scanner/scanner.go
+++ b/libgo/go/scanner/scanner.go
@@ -93,7 +93,7 @@ const (
 	skipComment
 )
 
-var tokenString = map[int]string{
+var tokenString = map[rune]string{
 	EOF:       "EOF",
 	Ident:     "Ident",
 	Int:       "Int",
@@ -105,7 +105,7 @@ var tokenString = map[int]string{
 }
 
 // TokenString returns a (visible) string for a token or Unicode character.
-func TokenString(tok int) string {
+func TokenString(tok rune) string {
 	if s, found := tokenString[tok]; found {
 		return s
 	}
@@ -144,7 +144,7 @@ type Scanner struct {
 	tokEnd int          // token text tail end (srcBuf index)
 
 	// One character look-ahead
-	ch int // character before current srcPos
+	ch rune // character before current srcPos
 
 	// Error is called for each error encountered. If no Error
 	// function is set, the error is reported to os.Stderr.
@@ -218,8 +218,8 @@ func (s *Scanner) Init(src io.Reader) *Scanner {
 // that only a minimal amount of work needs to be done in the common ASCII
 // case (one test to check for both ASCII and end-of-buffer, and one test
 // to check for newlines).
-func (s *Scanner) next() int {
-	ch, width := int(s.srcBuf[s.srcPos]), 1
+func (s *Scanner) next() rune {
+	ch, width := rune(s.srcBuf[s.srcPos]), 1
 
 	if ch >= utf8.RuneSelf {
 		// uncommon case: not ASCII or not enough bytes
@@ -264,7 +264,7 @@ func (s *Scanner) next() int {
 			}
 		}
 		// at least one byte
-		ch = int(s.srcBuf[s.srcPos])
+		ch = rune(s.srcBuf[s.srcPos])
 		if ch >= utf8.RuneSelf {
 			// uncommon case: not ASCII
 			ch, width = utf8.DecodeRune(s.srcBuf[s.srcPos:s.srcEnd])
@@ -304,7 +304,7 @@ func (s *Scanner) next() int {
 // it prints an error message to os.Stderr. Next does not
 // update the Scanner's Position field; use Pos() to
 // get the current position.
-func (s *Scanner) Next() int {
+func (s *Scanner) Next() rune {
 	s.tokPos = -1 // don't collect token text
 	s.Line = 0    // invalidate token position
 	ch := s.Peek()
@@ -315,7 +315,7 @@ func (s *Scanner) Next() int {
 // Peek returns the next Unicode character in the source without advancing
 // the scanner. It returns EOF if the scanner's position is at the last
 // character of the source.
-func (s *Scanner) Peek() int {
+func (s *Scanner) Peek() rune {
 	if s.ch < 0 {
 		s.ch = s.next()
 	}
@@ -335,7 +335,7 @@ func (s *Scanner) error(msg string) {
 	fmt.Fprintf(os.Stderr, "%s: %s\n", pos, msg)
 }
 
-func (s *Scanner) scanIdentifier() int {
+func (s *Scanner) scanIdentifier() rune {
 	ch := s.next() // read character after first '_' or letter
 	for ch == '_' || unicode.IsLetter(ch) || unicode.IsDigit(ch) {
 		ch = s.next()
@@ -343,35 +343,35 @@ func (s *Scanner) scanIdentifier() int {
 	return ch
 }
 
-func digitVal(ch int) int {
+func digitVal(ch rune) int {
 	switch {
 	case '0' <= ch && ch <= '9':
-		return ch - '0'
+		return int(ch - '0')
 	case 'a' <= ch && ch <= 'f':
-		return ch - 'a' + 10
+		return int(ch - 'a' + 10)
 	case 'A' <= ch && ch <= 'F':
-		return ch - 'A' + 10
+		return int(ch - 'A' + 10)
 	}
 	return 16 // larger than any legal digit val
 }
 
-func isDecimal(ch int) bool { return '0' <= ch && ch <= '9' }
+func isDecimal(ch rune) bool { return '0' <= ch && ch <= '9' }
 
-func (s *Scanner) scanMantissa(ch int) int {
+func (s *Scanner) scanMantissa(ch rune) rune {
 	for isDecimal(ch) {
 		ch = s.next()
 	}
 	return ch
 }
 
-func (s *Scanner) scanFraction(ch int) int {
+func (s *Scanner) scanFraction(ch rune) rune {
 	if ch == '.' {
 		ch = s.scanMantissa(s.next())
 	}
 	return ch
 }
 
-func (s *Scanner) scanExponent(ch int) int {
+func (s *Scanner) scanExponent(ch rune) rune {
 	if ch == 'e' || ch == 'E' {
 		ch = s.next()
 		if ch == '-' || ch == '+' {
@@ -382,7 +382,7 @@ func (s *Scanner) scanExponent(ch int) int {
 	return ch
 }
 
-func (s *Scanner) scanNumber(ch int) (int, int) {
+func (s *Scanner) scanNumber(ch rune) (rune, rune) {
 	// isDecimal(ch)
 	if ch == '0' {
 		// int or float
@@ -426,7 +426,7 @@ func (s *Scanner) scanNumber(ch int) (int, int) {
 	return Int, ch
 }
 
-func (s *Scanner) scanDigits(ch, base, n int) int {
+func (s *Scanner) scanDigits(ch rune, base, n int) rune {
 	for n > 0 && digitVal(ch) < base {
 		ch = s.next()
 		n--
@@ -437,7 +437,7 @@ func (s *Scanner) scanDigits(ch, base, n int) int {
 	return ch
 }
 
-func (s *Scanner) scanEscape(quote int) int {
+func (s *Scanner) scanEscape(quote rune) rune {
 	ch := s.next() // read character after '/'
 	switch ch {
 	case 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', quote:
@@ -457,7 +457,7 @@ func (s *Scanner) scanEscape(quote int) int {
 	return ch
 }
 
-func (s *Scanner) scanString(quote int) (n int) {
+func (s *Scanner) scanString(quote rune) (n int) {
 	ch := s.next() // read character after quote
 	for ch != quote {
 		if ch == '\n' || ch < 0 {
@@ -491,7 +491,7 @@ func (s *Scanner) scanChar() {
 	}
 }
 
-func (s *Scanner) scanComment(ch int) int {
+func (s *Scanner) scanComment(ch rune) rune {
 	// ch == '/' || ch == '*'
 	if ch == '/' {
 		// line comment
@@ -524,7 +524,7 @@ func (s *Scanner) scanComment(ch int) int {
 // It returns EOF at the end of the source. It reports scanner errors (read and
 // token errors) by calling s.Error, if not nil; otherwise it prints an error
 // message to os.Stderr.
-func (s *Scanner) Scan() int {
+func (s *Scanner) Scan() rune {
 	ch := s.Peek()
 
 	// reset token text position
diff --git a/libgo/go/scanner/scanner_test.go b/libgo/go/scanner/scanner_test.go
index bbbba12..fb39883 100644
--- a/libgo/go/scanner/scanner_test.go
+++ b/libgo/go/scanner/scanner_test.go
@@ -64,7 +64,7 @@ func TestNext(t *testing.T) {
 }
 
 type token struct {
-	tok  int
+	tok  rune
 	text string
 }
 
@@ -233,7 +233,7 @@ func makeSource(pattern string) *bytes.Buffer {
 	return &buf
 }
 
-func checkTok(t *testing.T, s *Scanner, line, got, want int, text string) {
+func checkTok(t *testing.T, s *Scanner, line int, got, want rune, text string) {
 	if got != want {
 		t.Fatalf("tok = %s, want %s for %q", TokenString(got), TokenString(want), text)
 	}
@@ -329,7 +329,7 @@ func TestScanZeroMode(t *testing.T) {
 	}
 }
 
-func testScanSelectedMode(t *testing.T, mode uint, class int) {
+func testScanSelectedMode(t *testing.T, mode uint, class rune) {
 	src := makeSource("%s\n")
 	s := new(Scanner).Init(src)
 	s.Mode = mode
@@ -398,7 +398,7 @@ func TestScanWhitespace(t *testing.T) {
 	}
 }
 
-func testError(t *testing.T, src, pos, msg string, tok int) {
+func testError(t *testing.T, src, pos, msg string, tok rune) {
 	s := new(Scanner).Init(bytes.NewBufferString(src))
 	errorCalled := false
 	s.Error = func(s *Scanner, m string) {
@@ -463,7 +463,7 @@ func checkPos(t *testing.T, got, want Position) {
 	}
 }
 
-func checkNextPos(t *testing.T, s *Scanner, offset, line, column, char int) {
+func checkNextPos(t *testing.T, s *Scanner, offset, line, column int, char rune) {
 	if ch := s.Next(); ch != char {
 		t.Errorf("ch = %s, want %s", TokenString(ch), TokenString(char))
 	}
@@ -471,7 +471,7 @@ func checkNextPos(t *testing.T, s *Scanner, offset, line, column, char int) {
 	checkPos(t, s.Pos(), want)
 }
 
-func checkScanPos(t *testing.T, s *Scanner, offset, line, column, char int) {
+func checkScanPos(t *testing.T, s *Scanner, offset, line, column int, char rune) {
 	want := Position{Offset: offset, Line: line, Column: column}
 	checkPos(t, s.Pos(), want)
 	if ch := s.Scan(); ch != char {
diff --git a/libgo/go/smtp/smtp_test.go b/libgo/go/smtp/smtp_test.go
index c053557..553d3ae 100644
--- a/libgo/go/smtp/smtp_test.go
+++ b/libgo/go/smtp/smtp_test.go
@@ -37,14 +37,14 @@ testLoop:
 			t.Errorf("#%d got response %s, expected %s", i, resp, test.responses[0])
 		}
 		if err != nil {
-			t.Errorf("#%d error: %s", i, err.String())
+			t.Errorf("#%d error: %s", i, err)
 		}
 		for j := range test.challenges {
 			challenge := []byte(test.challenges[j])
 			expected := []byte(test.responses[j+1])
 			resp, err := test.auth.Next(challenge, true)
 			if err != nil {
-				t.Errorf("#%d error: %s", i, err.String())
+				t.Errorf("#%d error: %s", i, err)
 				continue testLoop
 			}
 			if !bytes.Equal(resp, expected) {
@@ -74,13 +74,13 @@ func TestBasic(t *testing.T) {
 	c := &Client{Text: textproto.NewConn(fake)}
 
 	if err := c.helo(); err != nil {
-		t.Fatalf("HELO failed: %s", err.String())
+		t.Fatalf("HELO failed: %s", err)
 	}
 	if err := c.ehlo(); err == nil {
 		t.Fatalf("Expected first EHLO to fail")
 	}
 	if err := c.ehlo(); err != nil {
-		t.Fatalf("Second EHLO failed: %s", err.String())
+		t.Fatalf("Second EHLO failed: %s", err)
 	}
 
 	if ok, args := c.Extension("aUtH"); !ok || args != "LOGIN PLAIN" {
@@ -105,14 +105,14 @@ func TestBasic(t *testing.T) {
 	c.tls = true
 	c.serverName = "smtp.google.com"
 	if err := c.Auth(PlainAuth("", "user", "pass", "smtp.google.com")); err != nil {
-		t.Fatalf("AUTH failed: %s", err.String())
+		t.Fatalf("AUTH failed: %s", err)
 	}
 
 	if err := c.Mail("user@gmail.com"); err != nil {
-		t.Fatalf("MAIL failed: %s", err.String())
+		t.Fatalf("MAIL failed: %s", err)
 	}
 	if err := c.Rcpt("golang-nuts@googlegroups.com"); err != nil {
-		t.Fatalf("RCPT failed: %s", err.String())
+		t.Fatalf("RCPT failed: %s", err)
 	}
 	msg := `From: user@gmail.com
 To: golang-nuts@googlegroups.com
@@ -123,17 +123,17 @@ Line 1
 Goodbye.`
 	w, err := c.Data()
 	if err != nil {
-		t.Fatalf("DATA failed: %s", err.String())
+		t.Fatalf("DATA failed: %s", err)
 	}
 	if _, err := w.Write([]byte(msg)); err != nil {
-		t.Fatalf("Data write failed: %s", err.String())
+		t.Fatalf("Data write failed: %s", err)
 	}
 	if err := w.Close(); err != nil {
-		t.Fatalf("Bad data response: %s", err.String())
+		t.Fatalf("Bad data response: %s", err)
 	}
 
 	if err := c.Quit(); err != nil {
-		t.Fatalf("QUIT failed: %s", err.String())
+		t.Fatalf("QUIT failed: %s", err)
 	}
 
 	bcmdbuf.Flush()
diff --git a/libgo/go/strconv/atob.go b/libgo/go/strconv/atob.go
index 98ce750..7208194 100644
--- a/libgo/go/strconv/atob.go
+++ b/libgo/go/strconv/atob.go
@@ -16,7 +16,7 @@ func Atob(str string) (value bool, err os.Error) {
 	case "0", "f", "F", "false", "FALSE", "False":
 		return false, nil
 	}
-	return false, &NumError{str, os.EINVAL}
+	return false, &NumError{str, ErrSyntax}
 }
 
 // Btoa returns "true" or "false" according to the value of the boolean argument
diff --git a/libgo/go/strconv/atob_test.go b/libgo/go/strconv/atob_test.go
index 541e60d..d9db6c7 100644
--- a/libgo/go/strconv/atob_test.go
+++ b/libgo/go/strconv/atob_test.go
@@ -17,8 +17,8 @@ type atobTest struct {
 }
 
 var atobtests = []atobTest{
-	{"", false, os.EINVAL},
-	{"asdf", false, os.EINVAL},
+	{"", false, ErrSyntax},
+	{"asdf", false, ErrSyntax},
 	{"0", false, nil},
 	{"f", false, nil},
 	{"F", false, nil},
diff --git a/libgo/go/strconv/atof.go b/libgo/go/strconv/atof.go
index 86c56f7..4a4b1b4 100644
--- a/libgo/go/strconv/atof.go
+++ b/libgo/go/strconv/atof.go
@@ -350,11 +350,11 @@ func (d *decimal) atof32() (f float32, ok bool) {
 // The errors that Atof32 returns have concrete type *NumError
 // and include err.Num = s.
 //
-// If s is not syntactically well-formed, Atof32 returns err.Error = os.EINVAL.
+// If s is not syntactically well-formed, Atof32 returns err.Error = ErrSyntax.
 //
 // If s is syntactically well-formed but is more than 1/2 ULP
 // away from the largest floating point number of the given size,
-// Atof32 returns f = ±Inf, err.Error = os.ERANGE.
+// Atof32 returns f = ±Inf, err.Error = ErrRange.
 func Atof32(s string) (f float32, err os.Error) {
 	if val, ok := special(s); ok {
 		return float32(val), nil
@@ -362,7 +362,7 @@ func Atof32(s string) (f float32, err os.Error) {
 
 	var d decimal
 	if !d.set(s) {
-		return 0, &NumError{s, os.EINVAL}
+		return 0, &NumError{s, ErrSyntax}
 	}
 	if optimize {
 		if f, ok := d.atof32(); ok {
@@ -372,7 +372,7 @@ func Atof32(s string) (f float32, err os.Error) {
 	b, ovf := d.floatBits(&float32info)
 	f = math.Float32frombits(uint32(b))
 	if ovf {
-		err = &NumError{s, os.ERANGE}
+		err = &NumError{s, ErrRange}
 	}
 	return f, err
 }
@@ -387,7 +387,7 @@ func Atof64(s string) (f float64, err os.Error) {
 
 	var d decimal
 	if !d.set(s) {
-		return 0, &NumError{s, os.EINVAL}
+		return 0, &NumError{s, ErrSyntax}
 	}
 	if optimize {
 		if f, ok := d.atof64(); ok {
@@ -397,7 +397,7 @@ func Atof64(s string) (f float64, err os.Error) {
 	b, ovf := d.floatBits(&float64info)
 	f = math.Float64frombits(b)
 	if ovf {
-		err = &NumError{s, os.ERANGE}
+		err = &NumError{s, ErrRange}
 	}
 	return f, err
 }
diff --git a/libgo/go/strconv/atof_test.go b/libgo/go/strconv/atof_test.go
index 23aafc1..33f881c 100644
--- a/libgo/go/strconv/atof_test.go
+++ b/libgo/go/strconv/atof_test.go
@@ -18,11 +18,11 @@ type atofTest struct {
 }
 
 var atoftests = []atofTest{
-	{"", "0", os.EINVAL},
+	{"", "0", ErrSyntax},
 	{"1", "1", nil},
 	{"+1", "1", nil},
-	{"1x", "0", os.EINVAL},
-	{"1.1.", "0", os.EINVAL},
+	{"1x", "0", ErrSyntax},
+	{"1.1.", "0", ErrSyntax},
 	{"1e23", "1e+23", nil},
 	{"1E23", "1e+23", nil},
 	{"100000000000000000000000", "1e+23", nil},
@@ -56,28 +56,28 @@ var atoftests = []atofTest{
 	{"1.7976931348623157e308", "1.7976931348623157e+308", nil},
 	{"-1.7976931348623157e308", "-1.7976931348623157e+308", nil},
 	// next float64 - too large
-	{"1.7976931348623159e308", "+Inf", os.ERANGE},
-	{"-1.7976931348623159e308", "-Inf", os.ERANGE},
+	{"1.7976931348623159e308", "+Inf", ErrRange},
+	{"-1.7976931348623159e308", "-Inf", ErrRange},
 	// the border is ...158079
 	// borderline - okay
 	{"1.7976931348623158e308", "1.7976931348623157e+308", nil},
 	{"-1.7976931348623158e308", "-1.7976931348623157e+308", nil},
 	// borderline - too large
-	{"1.797693134862315808e308", "+Inf", os.ERANGE},
-	{"-1.797693134862315808e308", "-Inf", os.ERANGE},
+	{"1.797693134862315808e308", "+Inf", ErrRange},
+	{"-1.797693134862315808e308", "-Inf", ErrRange},
 
 	// a little too large
 	{"1e308", "1e+308", nil},
-	{"2e308", "+Inf", os.ERANGE},
-	{"1e309", "+Inf", os.ERANGE},
+	{"2e308", "+Inf", ErrRange},
+	{"1e309", "+Inf", ErrRange},
 
 	// way too large
-	{"1e310", "+Inf", os.ERANGE},
-	{"-1e310", "-Inf", os.ERANGE},
-	{"1e400", "+Inf", os.ERANGE},
-	{"-1e400", "-Inf", os.ERANGE},
-	{"1e400000", "+Inf", os.ERANGE},
-	{"-1e400000", "-Inf", os.ERANGE},
+	{"1e310", "+Inf", ErrRange},
+	{"-1e310", "-Inf", ErrRange},
+	{"1e400", "+Inf", ErrRange},
+	{"-1e400", "-Inf", ErrRange},
+	{"1e400000", "+Inf", ErrRange},
+	{"-1e400000", "-Inf", ErrRange},
 
 	// denormalized
 	{"1e-305", "1e-305", nil},
@@ -99,14 +99,14 @@ var atoftests = []atofTest{
 
 	// try to overflow exponent
 	{"1e-4294967296", "0", nil},
-	{"1e+4294967296", "+Inf", os.ERANGE},
+	{"1e+4294967296", "+Inf", ErrRange},
 	{"1e-18446744073709551616", "0", nil},
-	{"1e+18446744073709551616", "+Inf", os.ERANGE},
+	{"1e+18446744073709551616", "+Inf", ErrRange},
 
 	// Parse errors
-	{"1e", "0", os.EINVAL},
-	{"1e-", "0", os.EINVAL},
-	{".e-1", "0", os.EINVAL},
+	{"1e", "0", ErrSyntax},
+	{"1e-", "0", ErrSyntax},
+	{".e-1", "0", ErrSyntax},
 
 	// http://www.exploringbinary.com/java-hangs-when-converting-2-2250738585072012e-308/
 	{"2.2250738585072012e-308", "2.2250738585072014e-308", nil},
diff --git a/libgo/go/strconv/atoi.go b/libgo/go/strconv/atoi.go
index 5845942..92ba89d 100644
--- a/libgo/go/strconv/atoi.go
+++ b/libgo/go/strconv/atoi.go
@@ -6,9 +6,16 @@ package strconv
 
 import "os"
 
+// ErrRange indicates that a value is out of range for the target type.
+var ErrRange = os.NewError("value out of range")
+
+// ErrSyntax indicates that a value does not have the right syntax for the target type.
+var ErrSyntax = os.NewError("invalid syntax")
+
+// A NumError records a failed conversion.
 type NumError struct {
-	Num   string
-	Error os.Error
+	Num   string   // the input
+	Error os.Error // the reason the conversion failed (ErrRange, ErrSyntax)
 }
 
 func (e *NumError) String() string { return `parsing "` + e.Num + `": ` + e.Error.String() }
@@ -38,15 +45,15 @@ func cutoff64(base int) uint64 {
 //
 // The errors that Btoui64 returns have concrete type *NumError
 // and include err.Num = s.  If s is empty or contains invalid
-// digits, err.Error = os.EINVAL; if the value corresponding
-// to s cannot be represented by a uint64, err.Error = os.ERANGE.
+// digits, err.Error = ErrSyntax; if the value corresponding
+// to s cannot be represented by a uint64, err.Error = ErrRange.
 func Btoui64(s string, b int) (n uint64, err os.Error) {
 	var cutoff uint64
 
 	s0 := s
 	switch {
 	case len(s) < 1:
-		err = os.EINVAL
+		err = ErrSyntax
 		goto Error
 
 	case 2 <= b && b <= 36:
@@ -59,7 +66,7 @@ func Btoui64(s string, b int) (n uint64, err os.Error) {
 			b = 16
 			s = s[2:]
 			if len(s) < 1 {
-				err = os.EINVAL
+				err = ErrSyntax
 				goto Error
 			}
 		case s[0] == '0':
@@ -88,19 +95,19 @@ func Btoui64(s string, b int) (n uint64, err os.Error) {
 			v = d - 'A' + 10
 		default:
 			n = 0
-			err = os.EINVAL
+			err = ErrSyntax
 			goto Error
 		}
 		if int(v) >= b {
 			n = 0
-			err = os.EINVAL
+			err = ErrSyntax
 			goto Error
 		}
 
 		if n >= cutoff {
 			// n*b overflows
 			n = 1<<64 - 1
-			err = os.ERANGE
+			err = ErrRange
 			goto Error
 		}
 		n *= uint64(b)
@@ -109,7 +116,7 @@ func Btoui64(s string, b int) (n uint64, err os.Error) {
 		if n1 < n {
 			// n+v overflows
 			n = 1<<64 - 1
-			err = os.ERANGE
+			err = ErrRange
 			goto Error
 		}
 		n = n1
@@ -124,8 +131,8 @@ Error:
 // Atoui64 interprets a string s as a decimal number and
 // returns the corresponding value n.
 //
-// Atoui64 returns err == os.EINVAL if s is empty or contains invalid digits.
-// It returns err == os.ERANGE if s cannot be represented by a uint64.
+// Atoui64 returns err.Error = ErrSyntax if s is empty or contains invalid digits.
+// It returns err.Error = ErrRange if s cannot be represented by a uint64.
 func Atoui64(s string) (n uint64, err os.Error) {
 	return Btoui64(s, 10)
 }
@@ -135,7 +142,7 @@ func Atoui64(s string) (n uint64, err os.Error) {
 func Btoi64(s string, base int) (i int64, err os.Error) {
 	// Empty string bad.
 	if len(s) == 0 {
-		return 0, &NumError{s, os.EINVAL}
+		return 0, &NumError{s, ErrSyntax}
 	}
 
 	// Pick off leading sign.
@@ -151,15 +158,15 @@ func Btoi64(s string, base int) (i int64, err os.Error) {
 	// Convert unsigned and check range.
 	var un uint64
 	un, err = Btoui64(s, base)
-	if err != nil && err.(*NumError).Error != os.ERANGE {
+	if err != nil && err.(*NumError).Error != ErrRange {
 		err.(*NumError).Num = s0
 		return 0, err
 	}
 	if !neg && un >= 1<<63 {
-		return 1<<63 - 1, &NumError{s0, os.ERANGE}
+		return 1<<63 - 1, &NumError{s0, ErrRange}
 	}
 	if neg && un > 1<<63 {
-		return -1 << 63, &NumError{s0, os.ERANGE}
+		return -1 << 63, &NumError{s0, ErrRange}
 	}
 	n := int64(un)
 	if neg {
@@ -175,12 +182,12 @@ func Atoi64(s string) (i int64, err os.Error) { return Btoi64(s, 10) }
 // Atoui is like Atoui64 but returns its result as a uint.
 func Atoui(s string) (i uint, err os.Error) {
 	i1, e1 := Atoui64(s)
-	if e1 != nil && e1.(*NumError).Error != os.ERANGE {
+	if e1 != nil && e1.(*NumError).Error != ErrRange {
 		return 0, e1
 	}
 	i = uint(i1)
 	if uint64(i) != i1 {
-		return ^uint(0), &NumError{s, os.ERANGE}
+		return ^uint(0), &NumError{s, ErrRange}
 	}
 	return i, nil
 }
@@ -188,15 +195,15 @@ func Atoui(s string) (i uint, err os.Error) {
 // Atoi is like Atoi64 but returns its result as an int.
 func Atoi(s string) (i int, err os.Error) {
 	i1, e1 := Atoi64(s)
-	if e1 != nil && e1.(*NumError).Error != os.ERANGE {
+	if e1 != nil && e1.(*NumError).Error != ErrRange {
 		return 0, e1
 	}
 	i = int(i1)
 	if int64(i) != i1 {
 		if i1 < 0 {
-			return -1 << (IntSize - 1), &NumError{s, os.ERANGE}
+			return -1 << (IntSize - 1), &NumError{s, ErrRange}
 		}
-		return 1<<(IntSize-1) - 1, &NumError{s, os.ERANGE}
+		return 1<<(IntSize-1) - 1, &NumError{s, ErrRange}
 	}
 	return i, nil
 }
diff --git a/libgo/go/strconv/atoi_test.go b/libgo/go/strconv/atoi_test.go
index 0b9f295..0d2e381 100644
--- a/libgo/go/strconv/atoi_test.go
+++ b/libgo/go/strconv/atoi_test.go
@@ -18,36 +18,36 @@ type atoui64Test struct {
 }
 
 var atoui64tests = []atoui64Test{
-	{"", 0, os.EINVAL},
+	{"", 0, ErrSyntax},
 	{"0", 0, nil},
 	{"1", 1, nil},
 	{"12345", 12345, nil},
 	{"012345", 12345, nil},
-	{"12345x", 0, os.EINVAL},
+	{"12345x", 0, ErrSyntax},
 	{"98765432100", 98765432100, nil},
 	{"18446744073709551615", 1<<64 - 1, nil},
-	{"18446744073709551616", 1<<64 - 1, os.ERANGE},
-	{"18446744073709551620", 1<<64 - 1, os.ERANGE},
+	{"18446744073709551616", 1<<64 - 1, ErrRange},
+	{"18446744073709551620", 1<<64 - 1, ErrRange},
 }
 
 var btoui64tests = []atoui64Test{
-	{"", 0, os.EINVAL},
+	{"", 0, ErrSyntax},
 	{"0", 0, nil},
 	{"1", 1, nil},
 	{"12345", 12345, nil},
 	{"012345", 012345, nil},
 	{"0x12345", 0x12345, nil},
 	{"0X12345", 0x12345, nil},
-	{"12345x", 0, os.EINVAL},
+	{"12345x", 0, ErrSyntax},
 	{"98765432100", 98765432100, nil},
 	{"18446744073709551615", 1<<64 - 1, nil},
-	{"18446744073709551616", 1<<64 - 1, os.ERANGE},
-	{"18446744073709551620", 1<<64 - 1, os.ERANGE},
+	{"18446744073709551616", 1<<64 - 1, ErrRange},
+	{"18446744073709551620", 1<<64 - 1, ErrRange},
 	{"0xFFFFFFFFFFFFFFFF", 1<<64 - 1, nil},
-	{"0x10000000000000000", 1<<64 - 1, os.ERANGE},
+	{"0x10000000000000000", 1<<64 - 1, ErrRange},
 	{"01777777777777777777777", 1<<64 - 1, nil},
-	{"01777777777777777777778", 0, os.EINVAL},
-	{"02000000000000000000000", 1<<64 - 1, os.ERANGE},
+	{"01777777777777777777778", 0, ErrSyntax},
+	{"02000000000000000000000", 1<<64 - 1, ErrRange},
 	{"0200000000000000000000", 1 << 61, nil},
 }
 
@@ -58,7 +58,7 @@ type atoi64Test struct {
 }
 
 var atoi64tests = []atoi64Test{
-	{"", 0, os.EINVAL},
+	{"", 0, ErrSyntax},
 	{"0", 0, nil},
 	{"-0", 0, nil},
 	{"1", 1, nil},
@@ -71,14 +71,14 @@ var atoi64tests = []atoi64Test{
 	{"-98765432100", -98765432100, nil},
 	{"9223372036854775807", 1<<63 - 1, nil},
 	{"-9223372036854775807", -(1<<63 - 1), nil},
-	{"9223372036854775808", 1<<63 - 1, os.ERANGE},
+	{"9223372036854775808", 1<<63 - 1, ErrRange},
 	{"-9223372036854775808", -1 << 63, nil},
-	{"9223372036854775809", 1<<63 - 1, os.ERANGE},
-	{"-9223372036854775809", -1 << 63, os.ERANGE},
+	{"9223372036854775809", 1<<63 - 1, ErrRange},
+	{"-9223372036854775809", -1 << 63, ErrRange},
 }
 
 var btoi64tests = []atoi64Test{
-	{"", 0, os.EINVAL},
+	{"", 0, ErrSyntax},
 	{"0", 0, nil},
 	{"-0", 0, nil},
 	{"1", 1, nil},
@@ -89,16 +89,16 @@ var btoi64tests = []atoi64Test{
 	{"-012345", -012345, nil},
 	{"0x12345", 0x12345, nil},
 	{"-0X12345", -0x12345, nil},
-	{"12345x", 0, os.EINVAL},
-	{"-12345x", 0, os.EINVAL},
+	{"12345x", 0, ErrSyntax},
+	{"-12345x", 0, ErrSyntax},
 	{"98765432100", 98765432100, nil},
 	{"-98765432100", -98765432100, nil},
 	{"9223372036854775807", 1<<63 - 1, nil},
 	{"-9223372036854775807", -(1<<63 - 1), nil},
-	{"9223372036854775808", 1<<63 - 1, os.ERANGE},
+	{"9223372036854775808", 1<<63 - 1, ErrRange},
 	{"-9223372036854775808", -1 << 63, nil},
-	{"9223372036854775809", 1<<63 - 1, os.ERANGE},
-	{"-9223372036854775809", -1 << 63, os.ERANGE},
+	{"9223372036854775809", 1<<63 - 1, ErrRange},
+	{"-9223372036854775809", -1 << 63, ErrRange},
 }
 
 type atoui32Test struct {
@@ -108,15 +108,15 @@ type atoui32Test struct {
 }
 
 var atoui32tests = []atoui32Test{
-	{"", 0, os.EINVAL},
+	{"", 0, ErrSyntax},
 	{"0", 0, nil},
 	{"1", 1, nil},
 	{"12345", 12345, nil},
 	{"012345", 12345, nil},
-	{"12345x", 0, os.EINVAL},
+	{"12345x", 0, ErrSyntax},
 	{"987654321", 987654321, nil},
 	{"4294967295", 1<<32 - 1, nil},
-	{"4294967296", 1<<32 - 1, os.ERANGE},
+	{"4294967296", 1<<32 - 1, ErrRange},
 }
 
 type atoi32Test struct {
@@ -126,7 +126,7 @@ type atoi32Test struct {
 }
 
 var atoi32tests = []atoi32Test{
-	{"", 0, os.EINVAL},
+	{"", 0, ErrSyntax},
 	{"0", 0, nil},
 	{"-0", 0, nil},
 	{"1", 1, nil},
@@ -135,16 +135,16 @@ var atoi32tests = []atoi32Test{
 	{"-12345", -12345, nil},
 	{"012345", 12345, nil},
 	{"-012345", -12345, nil},
-	{"12345x", 0, os.EINVAL},
-	{"-12345x", 0, os.EINVAL},
+	{"12345x", 0, ErrSyntax},
+	{"-12345x", 0, ErrSyntax},
 	{"987654321", 987654321, nil},
 	{"-987654321", -987654321, nil},
 	{"2147483647", 1<<31 - 1, nil},
 	{"-2147483647", -(1<<31 - 1), nil},
-	{"2147483648", 1<<31 - 1, os.ERANGE},
+	{"2147483648", 1<<31 - 1, ErrRange},
 	{"-2147483648", -1 << 31, nil},
-	{"2147483649", 1<<31 - 1, os.ERANGE},
-	{"-2147483649", -1 << 31, os.ERANGE},
+	{"2147483649", 1<<31 - 1, ErrRange},
+	{"-2147483649", -1 << 31, ErrRange},
 }
 
 func init() {
diff --git a/libgo/go/strconv/fp_test.go b/libgo/go/strconv/fp_test.go
index 3096957..991d3ac 100644
--- a/libgo/go/strconv/fp_test.go
+++ b/libgo/go/strconv/fp_test.go
@@ -96,7 +96,7 @@ func myatof32(s string) (f float32, ok bool) {
 func TestFp(t *testing.T) {
 	f, err := os.Open("testfp.txt")
 	if err != nil {
-		t.Fatal("testfp: open testfp.txt:", err.String())
+		t.Fatal("testfp: open testfp.txt:", err)
 	}
 	defer f.Close()
 
diff --git a/libgo/go/strconv/quote.go b/libgo/go/strconv/quote.go
index bbb9783..7efdcfe 100644
--- a/libgo/go/strconv/quote.go
+++ b/libgo/go/strconv/quote.go
@@ -18,32 +18,32 @@ func quoteWith(s string, quote byte, ASCIIonly bool) string {
 	var buf bytes.Buffer
 	buf.WriteByte(quote)
 	for width := 0; len(s) > 0; s = s[width:] {
-		rune := int(s[0])
+		r := rune(s[0])
 		width = 1
-		if rune >= utf8.RuneSelf {
-			rune, width = utf8.DecodeRuneInString(s)
+		if r >= utf8.RuneSelf {
+			r, width = utf8.DecodeRuneInString(s)
 		}
-		if width == 1 && rune == utf8.RuneError {
+		if width == 1 && r == utf8.RuneError {
 			buf.WriteString(`\x`)
 			buf.WriteByte(lowerhex[s[0]>>4])
 			buf.WriteByte(lowerhex[s[0]&0xF])
 			continue
 		}
-		if rune == int(quote) || rune == '\\' { // always backslashed
+		if r == rune(quote) || r == '\\' { // always backslashed
 			buf.WriteByte('\\')
-			buf.WriteByte(byte(rune))
+			buf.WriteByte(byte(r))
 			continue
 		}
 		if ASCIIonly {
-			if rune <= unicode.MaxASCII && unicode.IsPrint(rune) {
-				buf.WriteRune(rune)
+			if r <= unicode.MaxASCII && unicode.IsPrint(r) {
+				buf.WriteRune(r)
 				continue
 			}
-		} else if unicode.IsPrint(rune) {
-			buf.WriteRune(rune)
+		} else if unicode.IsPrint(r) {
+			buf.WriteRune(r)
 			continue
 		}
-		switch rune {
+		switch r {
 		case '\a':
 			buf.WriteString(`\a`)
 		case '\b':
@@ -60,22 +60,22 @@ func quoteWith(s string, quote byte, ASCIIonly bool) string {
 			buf.WriteString(`\v`)
 		default:
 			switch {
-			case rune < ' ':
+			case r < ' ':
 				buf.WriteString(`\x`)
 				buf.WriteByte(lowerhex[s[0]>>4])
 				buf.WriteByte(lowerhex[s[0]&0xF])
-			case rune > unicode.MaxRune:
-				rune = 0xFFFD
+			case r > unicode.MaxRune:
+				r = 0xFFFD
 				fallthrough
-			case rune < 0x10000:
+			case r < 0x10000:
 				buf.WriteString(`\u`)
 				for s := 12; s >= 0; s -= 4 {
-					buf.WriteByte(lowerhex[rune>>uint(s)&0xF])
+					buf.WriteByte(lowerhex[r>>uint(s)&0xF])
 				}
 			default:
 				buf.WriteString(`\U`)
 				for s := 28; s >= 0; s -= 4 {
-					buf.WriteByte(lowerhex[rune>>uint(s)&0xF])
+					buf.WriteByte(lowerhex[r>>uint(s)&0xF])
 				}
 			}
 		}
@@ -130,8 +130,8 @@ func CanBackquote(s string) bool {
 	return true
 }
 
-func unhex(b byte) (v int, ok bool) {
-	c := int(b)
+func unhex(b byte) (v rune, ok bool) {
+	c := rune(b)
 	switch {
 	case '0' <= c && c <= '9':
 		return c - '0', true
@@ -157,22 +157,22 @@ func unhex(b byte) (v int, ok bool) {
 // If set to a single quote, it permits the sequence \' and disallows unescaped '.
 // If set to a double quote, it permits \" and disallows unescaped ".
 // If set to zero, it does not permit either escape and allows both quote characters to appear unescaped.
-func UnquoteChar(s string, quote byte) (value int, multibyte bool, tail string, err os.Error) {
+func UnquoteChar(s string, quote byte) (value rune, multibyte bool, tail string, err os.Error) {
 	// easy cases
 	switch c := s[0]; {
 	case c == quote && (quote == '\'' || quote == '"'):
-		err = os.EINVAL
+		err = ErrSyntax
 		return
 	case c >= utf8.RuneSelf:
 		r, size := utf8.DecodeRuneInString(s)
 		return r, true, s[size:], nil
 	case c != '\\':
-		return int(s[0]), false, s[1:], nil
+		return rune(s[0]), false, s[1:], nil
 	}
 
 	// hard case: c is backslash
 	if len(s) <= 1 {
-		err = os.EINVAL
+		err = ErrSyntax
 		return
 	}
 	c := s[1]
@@ -203,15 +203,15 @@ func UnquoteChar(s string, quote byte) (value int, multibyte bool, tail string,
 		case 'U':
 			n = 8
 		}
-		v := 0
+		var v rune
 		if len(s) < n {
-			err = os.EINVAL
+			err = ErrSyntax
 			return
 		}
 		for j := 0; j < n; j++ {
 			x, ok := unhex(s[j])
 			if !ok {
-				err = os.EINVAL
+				err = ErrSyntax
 				return
 			}
 			v = v<<4 | x
@@ -223,19 +223,19 @@ func UnquoteChar(s string, quote byte) (value int, multibyte bool, tail string,
 			break
 		}
 		if v > unicode.MaxRune {
-			err = os.EINVAL
+			err = ErrSyntax
 			return
 		}
 		value = v
 		multibyte = true
 	case '0', '1', '2', '3', '4', '5', '6', '7':
-		v := int(c) - '0'
+		v := rune(c) - '0'
 		if len(s) < 2 {
-			err = os.EINVAL
+			err = ErrSyntax
 			return
 		}
 		for j := 0; j < 2; j++ { // one digit already; two more
-			x := int(s[j]) - '0'
+			x := rune(s[j]) - '0'
 			if x < 0 || x > 7 {
 				return
 			}
@@ -243,7 +243,7 @@ func UnquoteChar(s string, quote byte) (value int, multibyte bool, tail string,
 		}
 		s = s[2:]
 		if v > 255 {
-			err = os.EINVAL
+			err = ErrSyntax
 			return
 		}
 		value = v
@@ -251,12 +251,12 @@ func UnquoteChar(s string, quote byte) (value int, multibyte bool, tail string,
 		value = '\\'
 	case '\'', '"':
 		if c != quote {
-			err = os.EINVAL
+			err = ErrSyntax
 			return
 		}
-		value = int(c)
+		value = rune(c)
 	default:
-		err = os.EINVAL
+		err = ErrSyntax
 		return
 	}
 	tail = s
@@ -271,29 +271,29 @@ func UnquoteChar(s string, quote byte) (value int, multibyte bool, tail string,
 func Unquote(s string) (t string, err os.Error) {
 	n := len(s)
 	if n < 2 {
-		return "", os.EINVAL
+		return "", ErrSyntax
 	}
 	quote := s[0]
 	if quote != s[n-1] {
-		return "", os.EINVAL
+		return "", ErrSyntax
 	}
 	s = s[1 : n-1]
 
 	if quote == '`' {
 		if strings.Contains(s, "`") {
-			return "", os.EINVAL
+			return "", ErrSyntax
 		}
 		return s, nil
 	}
 	if quote != '"' && quote != '\'' {
-		return "", os.EINVAL
+		return "", ErrSyntax
 	}
 	if strings.Index(s, "\n") >= 0 {
-		return "", os.EINVAL
+		return "", ErrSyntax
 	}
 
 	// Is it trivial?  Avoid allocation.
-	if strings.Index(s, `\`) < 0 && strings.IndexRune(s, int(quote)) < 0 {
+	if strings.Index(s, `\`) < 0 && strings.IndexRune(s, rune(quote)) < 0 {
 		switch quote {
 		case '"':
 			return s, nil
@@ -319,7 +319,7 @@ func Unquote(s string) (t string, err os.Error) {
 		}
 		if quote == '\'' && len(s) != 0 {
 			// single-quoted must be single character
-			return "", os.EINVAL
+			return "", ErrSyntax
 		}
 	}
 	return buf.String(), nil
diff --git a/libgo/go/strconv/quote_test.go b/libgo/go/strconv/quote_test.go
index 0311f77..9a59770 100644
--- a/libgo/go/strconv/quote_test.go
+++ b/libgo/go/strconv/quote_test.go
@@ -5,7 +5,6 @@
 package strconv_test
 
 import (
-	"os"
 	. "strconv"
 	"testing"
 )
@@ -210,8 +209,8 @@ func TestUnquote(t *testing.T) {
 	}
 
 	for _, s := range misquoted {
-		if out, err := Unquote(s); out != "" || err != os.EINVAL {
-			t.Errorf("Unquote(%#q) = %q, %v want %q, %v", s, out, err, "", os.EINVAL)
+		if out, err := Unquote(s); out != "" || err != ErrSyntax {
+			t.Errorf("Unquote(%#q) = %q, %v want %q, %v", s, out, err, "", ErrSyntax)
 		}
 	}
 }
diff --git a/libgo/go/strings/reader.go b/libgo/go/strings/reader.go
index eb515de..f4385a4 100644
--- a/libgo/go/strings/reader.go
+++ b/libgo/go/strings/reader.go
@@ -60,16 +60,16 @@ func (r *Reader) UnreadByte() os.Error {
 // If no bytes are available, the error returned is os.EOF.
 // If the bytes are an erroneous UTF-8 encoding, it
 // consumes one byte and returns U+FFFD, 1.
-func (r *Reader) ReadRune() (rune int, size int, err os.Error) {
+func (r *Reader) ReadRune() (ch rune, size int, err os.Error) {
 	if r.i >= len(r.s) {
 		return 0, 0, os.EOF
 	}
 	r.prevRune = r.i
 	if c := r.s[r.i]; c < utf8.RuneSelf {
 		r.i++
-		return int(c), 1, nil
+		return rune(c), 1, nil
 	}
-	rune, size = utf8.DecodeRuneInString(r.s[r.i:])
+	ch, size = utf8.DecodeRuneInString(r.s[r.i:])
 	r.i += size
 	return
 }
diff --git a/libgo/go/strings/replace_test.go b/libgo/go/strings/replace_test.go
index e337856..23c7e2e 100644
--- a/libgo/go/strings/replace_test.go
+++ b/libgo/go/strings/replace_test.go
@@ -159,12 +159,12 @@ func BenchmarkByteByteReplaces(b *testing.B) {
 // BenchmarkByteByteMap compares byteByteImpl against Map.
 func BenchmarkByteByteMap(b *testing.B) {
 	str := Repeat("a", 100) + Repeat("b", 100)
-	fn := func(r int) int {
+	fn := func(r rune) rune {
 		switch r {
 		case 'a':
-			return int('A')
+			return 'A'
 		case 'b':
-			return int('B')
+			return 'B'
 		}
 		return r
 	}
diff --git a/libgo/go/strings/strings.go b/libgo/go/strings/strings.go
index 58301fe..4f6e8a6 100644
--- a/libgo/go/strings/strings.go
+++ b/libgo/go/strings/strings.go
@@ -21,11 +21,12 @@ func explode(s string, n int) []string {
 		n = l
 	}
 	a := make([]string, n)
-	var size, rune int
+	var size int
+	var ch rune
 	i, cur := 0, 0
 	for ; i+1 < n; i++ {
-		rune, size = utf8.DecodeRuneInString(s[cur:])
-		a[i] = string(rune)
+		ch, size = utf8.DecodeRuneInString(s[cur:])
+		a[i] = string(ch)
 		cur += size
 	}
 	// add the rest, if there is any
@@ -117,11 +118,11 @@ func LastIndex(s, sep string) int {
 }
 
 // IndexRune returns the index of the first instance of the Unicode code point
-// rune, or -1 if rune is not present in s.
-func IndexRune(s string, rune int) int {
+// r, or -1 if rune is not present in s.
+func IndexRune(s string, r rune) int {
 	switch {
-	case rune < 0x80:
-		b := byte(rune)
+	case r < 0x80:
+		b := byte(r)
 		for i := 0; i < len(s); i++ {
 			if s[i] == b {
 				return i
@@ -129,7 +130,7 @@ func IndexRune(s string, rune int) int {
 		}
 	default:
 		for i, c := range s {
-			if c == rune {
+			if c == r {
 				return i
 			}
 		}
@@ -241,7 +242,7 @@ func Fields(s string) []string {
 // FieldsFunc splits the string s at each run of Unicode code points c satisfying f(c)
 // and returns an array of slices of s. If all code points in s satisfy f(c) or the
 // string is empty, an empty slice is returned.
-func FieldsFunc(s string, f func(int) bool) []string {
+func FieldsFunc(s string, f func(rune) bool) []string {
 	// First count the fields.
 	n := 0
 	inField := false
@@ -310,7 +311,7 @@ func HasSuffix(s, suffix string) bool {
 // Map returns a copy of the string s with all its characters modified
 // according to the mapping function. If mapping returns a negative value, the character is
 // dropped from the string with no replacement.
-func Map(mapping func(rune int) int, s string) string {
+func Map(mapping func(rune) rune, s string) string {
 	// In the worst case, the string can grow when mapped, making
 	// things unpleasant.  But it's so rare we barge in assuming it's
 	// fine.  It could also shrink but that falls out naturally.
@@ -321,18 +322,18 @@ func Map(mapping func(rune int) int, s string) string {
 	var b []byte
 
 	for i, c := range s {
-		rune := mapping(c)
+		r := mapping(c)
 		if b == nil {
-			if rune == c {
+			if r == c {
 				continue
 			}
 			b = make([]byte, maxbytes)
 			nbytes = copy(b, s[:i])
 		}
-		if rune >= 0 {
+		if r >= 0 {
 			wid := 1
-			if rune >= utf8.RuneSelf {
-				wid = utf8.RuneLen(rune)
+			if r >= utf8.RuneSelf {
+				wid = utf8.RuneLen(r)
 			}
 			if nbytes+wid > maxbytes {
 				// Grow the buffer.
@@ -341,7 +342,7 @@ func Map(mapping func(rune int) int, s string) string {
 				copy(nb, b[0:nbytes])
 				b = nb
 			}
-			nbytes += utf8.EncodeRune(b[nbytes:maxbytes], rune)
+			nbytes += utf8.EncodeRune(b[nbytes:maxbytes], r)
 		}
 	}
 	if b == nil {
@@ -375,44 +376,44 @@ func ToTitle(s string) string { return Map(unicode.ToTitle, s) }
 // ToUpperSpecial returns a copy of the string s with all Unicode letters mapped to their
 // upper case, giving priority to the special casing rules.
 func ToUpperSpecial(_case unicode.SpecialCase, s string) string {
-	return Map(func(r int) int { return _case.ToUpper(r) }, s)
+	return Map(func(r rune) rune { return _case.ToUpper(r) }, s)
 }
 
 // ToLowerSpecial returns a copy of the string s with all Unicode letters mapped to their
 // lower case, giving priority to the special casing rules.
 func ToLowerSpecial(_case unicode.SpecialCase, s string) string {
-	return Map(func(r int) int { return _case.ToLower(r) }, s)
+	return Map(func(r rune) rune { return _case.ToLower(r) }, s)
 }
 
 // ToTitleSpecial returns a copy of the string s with all Unicode letters mapped to their
 // title case, giving priority to the special casing rules.
 func ToTitleSpecial(_case unicode.SpecialCase, s string) string {
-	return Map(func(r int) int { return _case.ToTitle(r) }, s)
+	return Map(func(r rune) rune { return _case.ToTitle(r) }, s)
 }
 
 // isSeparator reports whether the rune could mark a word boundary.
 // TODO: update when package unicode captures more of the properties.
-func isSeparator(rune int) bool {
+func isSeparator(r rune) bool {
 	// ASCII alphanumerics and underscore are not separators
-	if rune <= 0x7F {
+	if r <= 0x7F {
 		switch {
-		case '0' <= rune && rune <= '9':
+		case '0' <= r && r <= '9':
 			return false
-		case 'a' <= rune && rune <= 'z':
+		case 'a' <= r && r <= 'z':
 			return false
-		case 'A' <= rune && rune <= 'Z':
+		case 'A' <= r && r <= 'Z':
 			return false
-		case rune == '_':
+		case r == '_':
 			return false
 		}
 		return true
 	}
 	// Letters and digits are not separators
-	if unicode.IsLetter(rune) || unicode.IsDigit(rune) {
+	if unicode.IsLetter(r) || unicode.IsDigit(r) {
 		return false
 	}
 	// Otherwise, all we can do for now is treat spaces as separators.
-	return unicode.IsSpace(rune)
+	return unicode.IsSpace(r)
 }
 
 // BUG(r): The rule Title uses for word boundaries does not handle Unicode punctuation properly.
@@ -423,9 +424,9 @@ func Title(s string) string {
 	// Use a closure here to remember state.
 	// Hackish but effective. Depends on Map scanning in order and calling
 	// the closure once per rune.
-	prev := ' '
+	prev := rune(' ')
 	return Map(
-		func(r int) int {
+		func(r rune) rune {
 			if isSeparator(prev) {
 				prev = r
 				return unicode.ToTitle(r)
@@ -438,7 +439,7 @@ func Title(s string) string {
 
 // TrimLeftFunc returns a slice of the string s with all leading
 // Unicode code points c satisfying f(c) removed.
-func TrimLeftFunc(s string, f func(r int) bool) string {
+func TrimLeftFunc(s string, f func(rune) bool) string {
 	i := indexFunc(s, f, false)
 	if i == -1 {
 		return ""
@@ -448,7 +449,7 @@ func TrimLeftFunc(s string, f func(r int) bool) string {
 
 // TrimRightFunc returns a slice of the string s with all trailing
 // Unicode code points c satisfying f(c) removed.
-func TrimRightFunc(s string, f func(r int) bool) string {
+func TrimRightFunc(s string, f func(rune) bool) string {
 	i := lastIndexFunc(s, f, false)
 	if i >= 0 && s[i] >= utf8.RuneSelf {
 		_, wid := utf8.DecodeRuneInString(s[i:])
@@ -461,34 +462,34 @@ func TrimRightFunc(s string, f func(r int) bool) string {
 
 // TrimFunc returns a slice of the string s with all leading
 // and trailing Unicode code points c satisfying f(c) removed.
-func TrimFunc(s string, f func(r int) bool) string {
+func TrimFunc(s string, f func(rune) bool) string {
 	return TrimRightFunc(TrimLeftFunc(s, f), f)
 }
 
 // IndexFunc returns the index into s of the first Unicode
 // code point satisfying f(c), or -1 if none do.
-func IndexFunc(s string, f func(r int) bool) int {
+func IndexFunc(s string, f func(rune) bool) int {
 	return indexFunc(s, f, true)
 }
 
 // LastIndexFunc returns the index into s of the last
 // Unicode code point satisfying f(c), or -1 if none do.
-func LastIndexFunc(s string, f func(r int) bool) int {
+func LastIndexFunc(s string, f func(rune) bool) int {
 	return lastIndexFunc(s, f, true)
 }
 
 // indexFunc is the same as IndexFunc except that if
 // truth==false, the sense of the predicate function is
 // inverted.
-func indexFunc(s string, f func(r int) bool, truth bool) int {
+func indexFunc(s string, f func(rune) bool, truth bool) int {
 	start := 0
 	for start < len(s) {
 		wid := 1
-		rune := int(s[start])
-		if rune >= utf8.RuneSelf {
-			rune, wid = utf8.DecodeRuneInString(s[start:])
+		r := rune(s[start])
+		if r >= utf8.RuneSelf {
+			r, wid = utf8.DecodeRuneInString(s[start:])
 		}
-		if f(rune) == truth {
+		if f(r) == truth {
 			return start
 		}
 		start += wid
@@ -499,19 +500,19 @@ func indexFunc(s string, f func(r int) bool, truth bool) int {
 // lastIndexFunc is the same as LastIndexFunc except that if
 // truth==false, the sense of the predicate function is
 // inverted.
-func lastIndexFunc(s string, f func(r int) bool, truth bool) int {
+func lastIndexFunc(s string, f func(rune) bool, truth bool) int {
 	for i := len(s); i > 0; {
-		rune, size := utf8.DecodeLastRuneInString(s[0:i])
+		r, size := utf8.DecodeLastRuneInString(s[0:i])
 		i -= size
-		if f(rune) == truth {
+		if f(r) == truth {
 			return i
 		}
 	}
 	return -1
 }
 
-func makeCutsetFunc(cutset string) func(rune int) bool {
-	return func(rune int) bool { return IndexRune(cutset, rune) != -1 }
+func makeCutsetFunc(cutset string) func(rune) bool {
+	return func(r rune) bool { return IndexRune(cutset, r) != -1 }
 }
 
 // Trim returns a slice of the string s with all leading and
@@ -589,15 +590,15 @@ func Replace(s, old, new string, n int) string {
 func EqualFold(s, t string) bool {
 	for s != "" && t != "" {
 		// Extract first rune from each string.
-		var sr, tr int
+		var sr, tr rune
 		if s[0] < utf8.RuneSelf {
-			sr, s = int(s[0]), s[1:]
+			sr, s = rune(s[0]), s[1:]
 		} else {
 			r, size := utf8.DecodeRuneInString(s)
 			sr, s = r, s[size:]
 		}
 		if t[0] < utf8.RuneSelf {
-			tr, t = int(t[0]), t[1:]
+			tr, t = rune(t[0]), t[1:]
 		} else {
 			r, size := utf8.DecodeRuneInString(t)
 			tr, t = r, t[size:]
diff --git a/libgo/go/strings/strings_test.go b/libgo/go/strings/strings_test.go
index 0859ddd..4132996 100644
--- a/libgo/go/strings/strings_test.go
+++ b/libgo/go/strings/strings_test.go
@@ -122,7 +122,7 @@ func TestLastIndexAny(t *testing.T) { runIndexTests(t, LastIndexAny, "LastIndexA
 
 var indexRuneTests = []struct {
 	s    string
-	rune int
+	rune rune
 	out  int
 }{
 	{"a A x", 'A', 2},
@@ -312,7 +312,7 @@ var FieldsFuncTests = []FieldsTest{
 }
 
 func TestFieldsFunc(t *testing.T) {
-	pred := func(c int) bool { return c == 'X' }
+	pred := func(c rune) bool { return c == 'X' }
 	for _, tt := range FieldsFuncTests {
 		a := FieldsFunc(tt.s, pred)
 		if !eq(a, tt.a) {
@@ -374,31 +374,31 @@ var trimSpaceTests = []StringTest{
 	{"x ☺ ", "x ☺"},
 }
 
-func tenRunes(rune int) string {
-	r := make([]int, 10)
+func tenRunes(ch rune) string {
+	r := make([]rune, 10)
 	for i := range r {
-		r[i] = rune
+		r[i] = ch
 	}
 	return string(r)
 }
 
 // User-defined self-inverse mapping function
-func rot13(rune int) int {
-	step := 13
-	if rune >= 'a' && rune <= 'z' {
-		return ((rune - 'a' + step) % 26) + 'a'
+func rot13(r rune) rune {
+	step := rune(13)
+	if r >= 'a' && r <= 'z' {
+		return ((r - 'a' + step) % 26) + 'a'
 	}
-	if rune >= 'A' && rune <= 'Z' {
-		return ((rune - 'A' + step) % 26) + 'A'
+	if r >= 'A' && r <= 'Z' {
+		return ((r - 'A' + step) % 26) + 'A'
 	}
-	return rune
+	return r
 }
 
 func TestMap(t *testing.T) {
 	// Run a couple of awful growth/shrinkage tests
 	a := tenRunes('a')
 	// 1.  Grow.  This triggers two reallocations in Map.
-	maxRune := func(rune int) int { return unicode.MaxRune }
+	maxRune := func(rune) rune { return unicode.MaxRune }
 	m := Map(maxRune, a)
 	expect := tenRunes(unicode.MaxRune)
 	if m != expect {
@@ -406,7 +406,7 @@ func TestMap(t *testing.T) {
 	}
 
 	// 2. Shrink
-	minRune := func(rune int) int { return 'a' }
+	minRune := func(rune) rune { return 'a' }
 	m = Map(minRune, tenRunes(unicode.MaxRune))
 	expect = a
 	if m != expect {
@@ -428,9 +428,9 @@ func TestMap(t *testing.T) {
 	}
 
 	// 5. Drop
-	dropNotLatin := func(rune int) int {
-		if unicode.Is(unicode.Latin, rune) {
-			return rune
+	dropNotLatin := func(r rune) rune {
+		if unicode.Is(unicode.Latin, r) {
+			return r
 		}
 		return -1
 	}
@@ -441,8 +441,8 @@ func TestMap(t *testing.T) {
 	}
 
 	// 6. Identity
-	identity := func(rune int) int {
-		return rune
+	identity := func(r rune) rune {
+		return r
 	}
 	orig := "Input string that we expect not to be copied."
 	m = Map(identity, orig)
@@ -457,8 +457,8 @@ func TestToUpper(t *testing.T) { runStringTests(t, ToUpper, "ToUpper", upperTest
 func TestToLower(t *testing.T) { runStringTests(t, ToLower, "ToLower", lowerTests) }
 
 func BenchmarkMapNoChanges(b *testing.B) {
-	identity := func(rune int) int {
-		return rune
+	identity := func(r rune) rune {
+		return r
 	}
 	for i := 0; i < b.N; i++ {
 		Map(identity, "Some string that won't be modified.")
@@ -536,7 +536,7 @@ func TestTrim(t *testing.T) {
 }
 
 type predicate struct {
-	f    func(r int) bool
+	f    func(rune) bool
 	name string
 }
 
@@ -544,7 +544,7 @@ var isSpace = predicate{unicode.IsSpace, "IsSpace"}
 var isDigit = predicate{unicode.IsDigit, "IsDigit"}
 var isUpper = predicate{unicode.IsUpper, "IsUpper"}
 var isValidRune = predicate{
-	func(r int) bool {
+	func(r rune) bool {
 		return r != utf8.RuneError
 	},
 	"IsValidRune",
@@ -552,7 +552,7 @@ var isValidRune = predicate{
 
 func not(p predicate) predicate {
 	return predicate{
-		func(r int) bool {
+		func(r rune) bool {
 			return !p.f(r)
 		},
 		"not " + p.name,
@@ -645,9 +645,9 @@ func TestCaseConsistency(t *testing.T) {
 	if testing.Short() {
 		numRunes = 1000
 	}
-	a := make([]int, numRunes)
+	a := make([]rune, numRunes)
 	for i := range a {
-		a[i] = i
+		a[i] = rune(i)
 	}
 	s := string(a)
 	// convert the cases.
@@ -706,7 +706,7 @@ func TestRepeat(t *testing.T) {
 	}
 }
 
-func runesEqual(a, b []int) bool {
+func runesEqual(a, b []rune) bool {
 	if len(a) != len(b) {
 		return false
 	}
@@ -720,30 +720,30 @@ func runesEqual(a, b []int) bool {
 
 var RunesTests = []struct {
 	in    string
-	out   []int
+	out   []rune
 	lossy bool
 }{
-	{"", []int{}, false},
-	{" ", []int{32}, false},
-	{"ABC", []int{65, 66, 67}, false},
-	{"abc", []int{97, 98, 99}, false},
-	{"\u65e5\u672c\u8a9e", []int{26085, 26412, 35486}, false},
-	{"ab\x80c", []int{97, 98, 0xFFFD, 99}, true},
-	{"ab\xc0c", []int{97, 98, 0xFFFD, 99}, true},
+	{"", []rune{}, false},
+	{" ", []rune{32}, false},
+	{"ABC", []rune{65, 66, 67}, false},
+	{"abc", []rune{97, 98, 99}, false},
+	{"\u65e5\u672c\u8a9e", []rune{26085, 26412, 35486}, false},
+	{"ab\x80c", []rune{97, 98, 0xFFFD, 99}, true},
+	{"ab\xc0c", []rune{97, 98, 0xFFFD, 99}, true},
 }
 
 func TestRunes(t *testing.T) {
 	for _, tt := range RunesTests {
-		a := []int(tt.in)
+		a := []rune(tt.in)
 		if !runesEqual(a, tt.out) {
-			t.Errorf("[]int(%q) = %v; want %v", tt.in, a, tt.out)
+			t.Errorf("[]rune(%q) = %v; want %v", tt.in, a, tt.out)
 			continue
 		}
 		if !tt.lossy {
 			// can only test reassembly if we didn't lose information
 			s := string(a)
 			if s != tt.in {
-				t.Errorf("string([]int(%q)) = %x; want %x", tt.in, s, tt.in)
+				t.Errorf("string([]rune(%q)) = %x; want %x", tt.in, s, tt.in)
 			}
 		}
 	}
diff --git a/libgo/go/template/exec.go b/libgo/go/template/exec.go
index e7fad72..34c6633 100644
--- a/libgo/go/template/exec.go
+++ b/libgo/go/template/exec.go
@@ -97,7 +97,7 @@ func (t *Template) Execute(wr io.Writer, data interface{}) (err os.Error) {
 		line: 1,
 		vars: []variable{{"$", value}},
 	}
-	if t.Root == nil {
+	if t.Tree == nil || t.Root == nil {
 		state.errorf("must be parsed before execution")
 	}
 	state.walk(value, t.Root)
diff --git a/libgo/go/template/exec_test.go b/libgo/go/template/exec_test.go
index 50b0ad2..2d2b402 100644
--- a/libgo/go/template/exec_test.go
+++ b/libgo/go/template/exec_test.go
@@ -98,7 +98,7 @@ var tVal = &T{
 	Empty3:            []int{7, 8},
 	Empty4:            &U{"UinEmpty"},
 	NonEmptyInterface: new(T),
-	Str:               os.NewError("foozle"),
+	Str:               bytes.NewBuffer([]byte("foozle")),
 	PI:                newInt(23),
 	PSI:               newIntSlice(21, 22, 23),
 	Tmpl:              Must(New("x").Parse("test template")), // "x" is the value of .X
@@ -644,7 +644,7 @@ func TestTree(t *testing.T) {
 	if err != nil {
 		t.Fatal("exec error:", err)
 	}
-	stripSpace := func(r int) int {
+	stripSpace := func(r rune) rune {
 		if r == '\t' || r == '\n' {
 			return -1
 		}
diff --git a/libgo/go/template/funcs.go b/libgo/go/template/funcs.go
index feb1fd8..938559e 100644
--- a/libgo/go/template/funcs.go
+++ b/libgo/go/template/funcs.go
@@ -279,7 +279,7 @@ func JSEscape(w io.Writer, b []byte) {
 	for i := 0; i < len(b); i++ {
 		c := b[i]
 
-		if !jsIsSpecial(int(c)) {
+		if !jsIsSpecial(rune(c)) {
 			// fast path: nothing to do
 			continue
 		}
@@ -307,12 +307,12 @@ func JSEscape(w io.Writer, b []byte) {
 			}
 		} else {
 			// Unicode rune.
-			rune, size := utf8.DecodeRune(b[i:])
-			if unicode.IsPrint(rune) {
+			r, size := utf8.DecodeRune(b[i:])
+			if unicode.IsPrint(r) {
 				w.Write(b[i : i+size])
 			} else {
 				// TODO(dsymonds): Do this without fmt?
-				fmt.Fprintf(w, "\\u%04X", rune)
+				fmt.Fprintf(w, "\\u%04X", r)
 			}
 			i += size - 1
 		}
@@ -332,12 +332,12 @@ func JSEscapeString(s string) string {
 	return b.String()
 }
 
-func jsIsSpecial(rune int) bool {
-	switch rune {
+func jsIsSpecial(r rune) bool {
+	switch r {
 	case '\\', '\'', '"', '<', '>':
 		return true
 	}
-	return rune < ' ' || utf8.RuneSelf <= rune
+	return r < ' ' || utf8.RuneSelf <= r
 }
 
 // JSEscaper returns the escaped JavaScript equivalent of the textual
diff --git a/libgo/go/template/parse/lex.go b/libgo/go/template/parse/lex.go
index 16ff590..04c105d 100644
--- a/libgo/go/template/parse/lex.go
+++ b/libgo/go/template/parse/lex.go
@@ -131,21 +131,21 @@ type lexer struct {
 }
 
 // next returns the next rune in the input.
-func (l *lexer) next() (rune int) {
+func (l *lexer) next() (r rune) {
 	if l.pos >= len(l.input) {
 		l.width = 0
 		return eof
 	}
-	rune, l.width = utf8.DecodeRuneInString(l.input[l.pos:])
+	r, l.width = utf8.DecodeRuneInString(l.input[l.pos:])
 	l.pos += l.width
-	return rune
+	return r
 }
 
 // peek returns but does not consume the next rune in the input.
-func (l *lexer) peek() int {
-	rune := l.next()
+func (l *lexer) peek() rune {
+	r := l.next()
 	l.backup()
-	return rune
+	return r
 }
 
 // backup steps back one rune. Can only be called once per call of next.
@@ -468,7 +468,7 @@ Loop:
 }
 
 // isSpace reports whether r is a space character.
-func isSpace(r int) bool {
+func isSpace(r rune) bool {
 	switch r {
 	case ' ', '\t', '\n', '\r':
 		return true
@@ -477,6 +477,6 @@ func isSpace(r int) bool {
 }
 
 // isAlphaNumeric reports whether r is an alphabetic, digit, or underscore.
-func isAlphaNumeric(r int) bool {
+func isAlphaNumeric(r rune) bool {
 	return r == '_' || unicode.IsLetter(r) || unicode.IsDigit(r)
 }
diff --git a/libgo/go/testing/quick/quick.go b/libgo/go/testing/quick/quick.go
index 756a60e..9ec1925 100644
--- a/libgo/go/testing/quick/quick.go
+++ b/libgo/go/testing/quick/quick.go
@@ -123,9 +123,9 @@ func Value(t reflect.Type, rand *rand.Rand) (value reflect.Value, ok bool) {
 		return s, true
 	case reflect.String:
 		numChars := rand.Intn(complexSize)
-		codePoints := make([]int, numChars)
+		codePoints := make([]rune, numChars)
 		for i := 0; i < numChars; i++ {
-			codePoints[i] = rand.Intn(0x10ffff)
+			codePoints[i] = rune(rand.Intn(0x10ffff))
 		}
 		return reflect.ValueOf(string(codePoints)), true
 	case reflect.Struct:
diff --git a/libgo/go/time/format.go b/libgo/go/time/format.go
index 50e96a5..1a629c9 100644
--- a/libgo/go/time/format.go
+++ b/libgo/go/time/format.go
@@ -45,12 +45,12 @@ const (
 	UnixDate = "Mon Jan _2 15:04:05 MST 2006"
 	RubyDate = "Mon Jan 02 15:04:05 -0700 2006"
 	RFC822   = "02 Jan 06 1504 MST"
-	// RFC822 with Zulu time.
-	RFC822Z = "02 Jan 06 1504 -0700"
-	RFC850  = "Monday, 02-Jan-06 15:04:05 MST"
-	RFC1123 = "Mon, 02 Jan 2006 15:04:05 MST"
-	RFC3339 = "2006-01-02T15:04:05Z07:00"
-	Kitchen = "3:04PM"
+	RFC822Z  = "02 Jan 06 1504 -0700" // RFC822 with numeric zone
+	RFC850   = "Monday, 02-Jan-06 15:04:05 MST"
+	RFC1123  = "Mon, 02 Jan 2006 15:04:05 MST"
+	RFC1123Z = "Mon, 02 Jan 2006 15:04:05 -0700" // RFC1123 with numeric zone
+	RFC3339  = "2006-01-02T15:04:05Z07:00"
+	Kitchen  = "3:04PM"
 	// Handy time stamps.
 	Stamp      = "Jan _2 15:04:05"
 	StampMilli = "Jan _2 15:04:05.000"
diff --git a/libgo/go/time/time_test.go b/libgo/go/time/time_test.go
index 353976c..e4cf513 100644
--- a/libgo/go/time/time_test.go
+++ b/libgo/go/time/time_test.go
@@ -201,6 +201,7 @@ var formatTests = []FormatTest{
 	{"RFC822", RFC822, "04 Feb 09 2100 PST"},
 	{"RFC850", RFC850, "Wednesday, 04-Feb-09 21:00:57 PST"},
 	{"RFC1123", RFC1123, "Wed, 04 Feb 2009 21:00:57 PST"},
+	{"RFC1123Z", RFC1123Z, "Wed, 04 Feb 2009 21:00:57 -0800"},
 	{"RFC3339", RFC3339, "2009-02-04T21:00:57-08:00"},
 	{"Kitchen", Kitchen, "9:00PM"},
 	{"am/pm", "3pm", "9pm"},
@@ -240,6 +241,7 @@ var parseTests = []ParseTest{
 	{"RubyDate", RubyDate, "Thu Feb 04 21:00:57 -0800 2010", true, true, 1, 0},
 	{"RFC850", RFC850, "Thursday, 04-Feb-10 21:00:57 PST", true, true, 1, 0},
 	{"RFC1123", RFC1123, "Thu, 04 Feb 2010 21:00:57 PST", true, true, 1, 0},
+	{"RFC1123Z", RFC1123Z, "Thu, 04 Feb 2010 21:00:57 -0800", true, true, 1, 0},
 	{"RFC3339", RFC3339, "2010-02-04T21:00:57-08:00", true, false, 1, 0},
 	{"custom: \"2006-01-02 15:04:05-07\"", "2006-01-02 15:04:05-07", "2010-02-04 21:00:57-08", true, false, 1, 0},
 	// Optional fractional seconds.
@@ -248,6 +250,7 @@ var parseTests = []ParseTest{
 	{"RubyDate", RubyDate, "Thu Feb 04 21:00:57.012 -0800 2010", true, true, 1, 3},
 	{"RFC850", RFC850, "Thursday, 04-Feb-10 21:00:57.0123 PST", true, true, 1, 4},
 	{"RFC1123", RFC1123, "Thu, 04 Feb 2010 21:00:57.01234 PST", true, true, 1, 5},
+	{"RFC1123Z", RFC1123Z, "Thu, 04 Feb 2010 21:00:57.01234 -0800", true, true, 1, 5},
 	{"RFC3339", RFC3339, "2010-02-04T21:00:57.012345678-08:00", true, false, 1, 9},
 	// Amount of white space should not matter.
 	{"ANSIC", ANSIC, "Thu Feb 4 21:00:57 2010", false, true, 1, 0},
diff --git a/libgo/go/unicode/digit.go b/libgo/go/unicode/digit.go
index 6793fd7..4800bd6 100644
--- a/libgo/go/unicode/digit.go
+++ b/libgo/go/unicode/digit.go
@@ -5,9 +5,9 @@
 package unicode
 
 // IsDigit reports whether the rune is a decimal digit.
-func IsDigit(rune int) bool {
-	if rune <= MaxLatin1 {
-		return '0' <= rune && rune <= '9'
+func IsDigit(r rune) bool {
+	if r <= MaxLatin1 {
+		return '0' <= r && r <= '9'
 	}
-	return Is(Digit, rune)
+	return Is(Digit, r)
 }
diff --git a/libgo/go/unicode/digit_test.go b/libgo/go/unicode/digit_test.go
index ae3c0ec..551c42a 100644
--- a/libgo/go/unicode/digit_test.go
+++ b/libgo/go/unicode/digit_test.go
@@ -9,7 +9,7 @@ import (
 	. "unicode"
 )
 
-var testDigit = []int{
+var testDigit = []rune{
 	0x0030,
 	0x0039,
 	0x0661,
@@ -68,7 +68,7 @@ var testDigit = []int{
 	0x1D7CE,
 }
 
-var testLetter = []int{
+var testLetter = []rune{
 	0x0041,
 	0x0061,
 	0x00AA,
@@ -118,7 +118,7 @@ func TestDigit(t *testing.T) {
 
 // Test that the special case in IsDigit agrees with the table
 func TestDigitOptimization(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		if Is(Digit, i) != IsDigit(i) {
 			t.Errorf("IsDigit(U+%04X) disagrees with Is(Digit)", i)
 		}
diff --git a/libgo/go/unicode/graphic.go b/libgo/go/unicode/graphic.go
index d482aac..9343bc9 100644
--- a/libgo/go/unicode/graphic.go
+++ b/libgo/go/unicode/graphic.go
@@ -31,13 +31,13 @@ var PrintRanges = []*RangeTable{
 // IsGraphic reports whether the rune is defined as a Graphic by Unicode.
 // Such characters include letters, marks, numbers, punctuation, symbols, and
 // spaces, from categories L, M, N, P, S, Zs.
-func IsGraphic(rune int) bool {
+func IsGraphic(r rune) bool {
 	// We cast to uint32 to avoid the extra test for negative,
 	// and in the index we cast to uint8 to avoid the range check.
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&pg != 0
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pg != 0
 	}
-	return IsOneOf(GraphicRanges, rune)
+	return IsOneOf(GraphicRanges, r)
 }
 
 // IsPrint reports whether the rune is defined as printable by Go. Such
@@ -45,18 +45,18 @@ func IsGraphic(rune int) bool {
 // ASCII space character, from categories L, M, N, P, S and the ASCII space
 // character.  This categorization is the same as IsGraphic except that the
 // only spacing character is ASCII space, U+0020.
-func IsPrint(rune int) bool {
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&pp != 0
+func IsPrint(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pp != 0
 	}
-	return IsOneOf(PrintRanges, rune)
+	return IsOneOf(PrintRanges, r)
 }
 
 // IsOneOf reports whether the rune is a member of one of the ranges.
 // The rune is known to be above Latin-1.
-func IsOneOf(set []*RangeTable, rune int) bool {
+func IsOneOf(set []*RangeTable, r rune) bool {
 	for _, inside := range set {
-		if Is(inside, rune) {
+		if Is(inside, r) {
 			return true
 		}
 	}
@@ -66,43 +66,43 @@ func IsOneOf(set []*RangeTable, rune int) bool {
 // IsControl reports whether the rune is a control character.
 // The C (Other) Unicode category includes more code points
 // such as surrogates; use Is(C, rune) to test for them.
-func IsControl(rune int) bool {
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&pC != 0
+func IsControl(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pC != 0
 	}
 	// All control characters are < Latin1Max.
 	return false
 }
 
 // IsLetter reports whether the rune is a letter (category L).
-func IsLetter(rune int) bool {
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&(pLu|pLl) != 0
+func IsLetter(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&(pLu|pLl) != 0
 	}
-	return Is(Letter, rune)
+	return Is(Letter, r)
 }
 
 // IsMark reports whether the rune is a mark character (category M).
-func IsMark(rune int) bool {
+func IsMark(r rune) bool {
 	// There are no mark characters in Latin-1.
-	return Is(Mark, rune)
+	return Is(Mark, r)
 }
 
 // IsNumber reports whether the rune is a number (category N).
-func IsNumber(rune int) bool {
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&pN != 0
+func IsNumber(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pN != 0
 	}
-	return Is(Number, rune)
+	return Is(Number, r)
 }
 
 // IsPunct reports whether the rune is a Unicode punctuation character
 // (category P).
-func IsPunct(rune int) bool {
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&pP != 0
+func IsPunct(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pP != 0
 	}
-	return Is(Punct, rune)
+	return Is(Punct, r)
 }
 
 // IsSpace reports whether the rune is a space character as defined
@@ -111,22 +111,22 @@ func IsPunct(rune int) bool {
 //	'\t', '\n', '\v', '\f', '\r', ' ', U+0085 (NEL), U+00A0 (NBSP).
 // Other definitions of spacing characters are set by category
 // Z and property Pattern_White_Space.
-func IsSpace(rune int) bool {
+func IsSpace(r rune) bool {
 	// This property isn't the same as Z; special-case it.
-	if uint32(rune) <= MaxLatin1 {
-		switch rune {
+	if uint32(r) <= MaxLatin1 {
+		switch r {
 		case '\t', '\n', '\v', '\f', '\r', ' ', 0x85, 0xA0:
 			return true
 		}
 		return false
 	}
-	return Is(White_Space, rune)
+	return Is(White_Space, r)
 }
 
 // IsSymbol reports whether the rune is a symbolic character.
-func IsSymbol(rune int) bool {
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&pS != 0
+func IsSymbol(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pS != 0
 	}
-	return Is(Symbol, rune)
+	return Is(Symbol, r)
 }
diff --git a/libgo/go/unicode/graphic_test.go b/libgo/go/unicode/graphic_test.go
index 77c679f..7b1f620 100644
--- a/libgo/go/unicode/graphic_test.go
+++ b/libgo/go/unicode/graphic_test.go
@@ -13,7 +13,7 @@ import (
 // in the Latin-1 range through the property table.
 
 func TestIsControlLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsControl(i)
 		want := false
 		switch {
@@ -29,7 +29,7 @@ func TestIsControlLatin1(t *testing.T) {
 }
 
 func TestIsLetterLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsLetter(i)
 		want := Is(Letter, i)
 		if got != want {
@@ -39,7 +39,7 @@ func TestIsLetterLatin1(t *testing.T) {
 }
 
 func TestIsUpperLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsUpper(i)
 		want := Is(Upper, i)
 		if got != want {
@@ -49,7 +49,7 @@ func TestIsUpperLatin1(t *testing.T) {
 }
 
 func TestIsLowerLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsLower(i)
 		want := Is(Lower, i)
 		if got != want {
@@ -59,7 +59,7 @@ func TestIsLowerLatin1(t *testing.T) {
 }
 
 func TestNumberLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsNumber(i)
 		want := Is(Number, i)
 		if got != want {
@@ -69,7 +69,7 @@ func TestNumberLatin1(t *testing.T) {
 }
 
 func TestIsPrintLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsPrint(i)
 		want := IsOneOf(PrintRanges, i)
 		if i == ' ' {
@@ -82,7 +82,7 @@ func TestIsPrintLatin1(t *testing.T) {
 }
 
 func TestIsGraphicLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsGraphic(i)
 		want := IsOneOf(GraphicRanges, i)
 		if got != want {
@@ -92,7 +92,7 @@ func TestIsGraphicLatin1(t *testing.T) {
 }
 
 func TestIsPunctLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsPunct(i)
 		want := Is(Punct, i)
 		if got != want {
@@ -102,7 +102,7 @@ func TestIsPunctLatin1(t *testing.T) {
 }
 
 func TestIsSpaceLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsSpace(i)
 		want := Is(White_Space, i)
 		if got != want {
@@ -112,7 +112,7 @@ func TestIsSpaceLatin1(t *testing.T) {
 }
 
 func TestIsSymbolLatin1(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		got := IsSymbol(i)
 		want := Is(Symbol, i)
 		if got != want {
diff --git a/libgo/go/unicode/letter.go b/libgo/go/unicode/letter.go
index 38a11c4..01c485b 100644
--- a/libgo/go/unicode/letter.go
+++ b/libgo/go/unicode/letter.go
@@ -71,7 +71,7 @@ const (
 	MaxCase
 )
 
-type d [MaxCase]int32 // to make the CaseRanges text shorter
+type d [MaxCase]rune // to make the CaseRanges text shorter
 
 // If the Delta field of a CaseRange is UpperLower or LowerUpper, it means
 // this CaseRange represents a sequence of the form (say)
@@ -81,17 +81,17 @@ const (
 )
 
 // is16 uses binary search to test whether rune is in the specified slice of 16-bit ranges.
-func is16(ranges []Range16, rune uint16) bool {
+func is16(ranges []Range16, r uint16) bool {
 	// binary search over ranges
 	lo := 0
 	hi := len(ranges)
 	for lo < hi {
 		m := lo + (hi-lo)/2
-		r := ranges[m]
-		if r.Lo <= rune && rune <= r.Hi {
-			return (rune-r.Lo)%r.Stride == 0
+		range_ := ranges[m]
+		if range_.Lo <= r && r <= range_.Hi {
+			return (r-range_.Lo)%range_.Stride == 0
 		}
-		if rune < r.Lo {
+		if r < range_.Lo {
 			hi = m
 		} else {
 			lo = m + 1
@@ -101,17 +101,17 @@ func is16(ranges []Range16, rune uint16) bool {
 }
 
 // is32 uses binary search to test whether rune is in the specified slice of 32-bit ranges.
-func is32(ranges []Range32, rune uint32) bool {
+func is32(ranges []Range32, r uint32) bool {
 	// binary search over ranges
 	lo := 0
 	hi := len(ranges)
 	for lo < hi {
 		m := lo + (hi-lo)/2
-		r := ranges[m]
-		if r.Lo <= rune && rune <= r.Hi {
-			return (rune-r.Lo)%r.Stride == 0
+		range_ := ranges[m]
+		if range_.Lo <= r && r <= range_.Hi {
+			return (r-range_.Lo)%range_.Stride == 0
 		}
-		if rune < r.Lo {
+		if r < range_.Lo {
 			hi = m
 		} else {
 			lo = m + 1
@@ -121,11 +121,11 @@ func is32(ranges []Range32, rune uint32) bool {
 }
 
 // Is tests whether rune is in the specified table of ranges.
-func Is(rangeTab *RangeTable, rune int) bool {
+func Is(rangeTab *RangeTable, r rune) bool {
 	// common case: rune is ASCII or Latin-1.
-	if uint32(rune) <= MaxLatin1 {
+	if uint32(r) <= MaxLatin1 {
 		// Only need to check R16, since R32 is always >= 1<<16.
-		r16 := uint16(rune)
+		r16 := uint16(r)
 		for _, r := range rangeTab.R16 {
 			if r16 > r.Hi {
 				continue
@@ -138,44 +138,44 @@ func Is(rangeTab *RangeTable, rune int) bool {
 		return false
 	}
 	r16 := rangeTab.R16
-	if len(r16) > 0 && rune <= int(r16[len(r16)-1].Hi) {
-		return is16(r16, uint16(rune))
+	if len(r16) > 0 && r <= rune(r16[len(r16)-1].Hi) {
+		return is16(r16, uint16(r))
 	}
 	r32 := rangeTab.R32
-	if len(r32) > 0 && rune >= int(r32[0].Lo) {
-		return is32(r32, uint32(rune))
+	if len(r32) > 0 && r >= rune(r32[0].Lo) {
+		return is32(r32, uint32(r))
 	}
 	return false
 }
 
 // IsUpper reports whether the rune is an upper case letter.
-func IsUpper(rune int) bool {
+func IsUpper(r rune) bool {
 	// See comment in IsGraphic.
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&pLu != 0
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pLu != 0
 	}
-	return Is(Upper, rune)
+	return Is(Upper, r)
 }
 
 // IsLower reports whether the rune is a lower case letter.
-func IsLower(rune int) bool {
+func IsLower(r rune) bool {
 	// See comment in IsGraphic.
-	if uint32(rune) <= MaxLatin1 {
-		return properties[uint8(rune)]&pLl != 0
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pLl != 0
 	}
-	return Is(Lower, rune)
+	return Is(Lower, r)
 }
 
 // IsTitle reports whether the rune is a title case letter.
-func IsTitle(rune int) bool {
-	if rune <= MaxLatin1 {
+func IsTitle(r rune) bool {
+	if r <= MaxLatin1 {
 		return false
 	}
-	return Is(Title, rune)
+	return Is(Title, r)
 }
 
 // to maps the rune using the specified case mapping.
-func to(_case int, rune int, caseRange []CaseRange) int {
+func to(_case int, r rune, caseRange []CaseRange) rune {
 	if _case < 0 || MaxCase <= _case {
 		return ReplacementChar // as reasonable an error as any
 	}
@@ -184,9 +184,9 @@ func to(_case int, rune int, caseRange []CaseRange) int {
 	hi := len(caseRange)
 	for lo < hi {
 		m := lo + (hi-lo)/2
-		r := caseRange[m]
-		if int(r.Lo) <= rune && rune <= int(r.Hi) {
-			delta := int(r.Delta[_case])
+		cr := caseRange[m]
+		if rune(cr.Lo) <= r && r <= rune(cr.Hi) {
+			delta := rune(cr.Delta[_case])
 			if delta > MaxRune {
 				// In an Upper-Lower sequence, which always starts with
 				// an UpperCase letter, the real deltas always look like:
@@ -198,82 +198,82 @@ func to(_case int, rune int, caseRange []CaseRange) int {
 				// bit in the sequence offset.
 				// The constants UpperCase and TitleCase are even while LowerCase
 				// is odd so we take the low bit from _case.
-				return int(r.Lo) + ((rune-int(r.Lo))&^1 | _case&1)
+				return rune(cr.Lo) + ((r-rune(cr.Lo))&^1 | rune(_case&1))
 			}
-			return rune + delta
+			return r + delta
 		}
-		if rune < int(r.Lo) {
+		if r < rune(cr.Lo) {
 			hi = m
 		} else {
 			lo = m + 1
 		}
 	}
-	return rune
+	return r
 }
 
 // To maps the rune to the specified case: UpperCase, LowerCase, or TitleCase.
-func To(_case int, rune int) int {
-	return to(_case, rune, CaseRanges)
+func To(_case int, r rune) rune {
+	return to(_case, r, CaseRanges)
 }
 
 // ToUpper maps the rune to upper case.
-func ToUpper(rune int) int {
-	if rune <= MaxASCII {
-		if 'a' <= rune && rune <= 'z' {
-			rune -= 'a' - 'A'
+func ToUpper(r rune) rune {
+	if r <= MaxASCII {
+		if 'a' <= r && r <= 'z' {
+			r -= 'a' - 'A'
 		}
-		return rune
+		return r
 	}
-	return To(UpperCase, rune)
+	return To(UpperCase, r)
 }
 
 // ToLower maps the rune to lower case.
-func ToLower(rune int) int {
-	if rune <= MaxASCII {
-		if 'A' <= rune && rune <= 'Z' {
-			rune += 'a' - 'A'
+func ToLower(r rune) rune {
+	if r <= MaxASCII {
+		if 'A' <= r && r <= 'Z' {
+			r += 'a' - 'A'
 		}
-		return rune
+		return r
 	}
-	return To(LowerCase, rune)
+	return To(LowerCase, r)
 }
 
 // ToTitle maps the rune to title case.
-func ToTitle(rune int) int {
-	if rune <= MaxASCII {
-		if 'a' <= rune && rune <= 'z' { // title case is upper case for ASCII
-			rune -= 'a' - 'A'
+func ToTitle(r rune) rune {
+	if r <= MaxASCII {
+		if 'a' <= r && r <= 'z' { // title case is upper case for ASCII
+			r -= 'a' - 'A'
 		}
-		return rune
+		return r
 	}
-	return To(TitleCase, rune)
+	return To(TitleCase, r)
 }
 
 // ToUpper maps the rune to upper case giving priority to the special mapping.
-func (special SpecialCase) ToUpper(rune int) int {
-	r := to(UpperCase, rune, []CaseRange(special))
-	if r == rune {
-		r = ToUpper(rune)
+func (special SpecialCase) ToUpper(r rune) rune {
+	r1 := to(UpperCase, r, []CaseRange(special))
+	if r1 == r {
+		r1 = ToUpper(r)
 	}
-	return r
+	return r1
 }
 
 // ToTitle maps the rune to title case giving priority to the special mapping.
-func (special SpecialCase) ToTitle(rune int) int {
-	r := to(TitleCase, rune, []CaseRange(special))
-	if r == rune {
-		r = ToTitle(rune)
+func (special SpecialCase) ToTitle(r rune) rune {
+	r1 := to(TitleCase, r, []CaseRange(special))
+	if r1 == r {
+		r1 = ToTitle(r)
 	}
-	return r
+	return r1
 }
 
 // ToLower maps the rune to lower case giving priority to the special mapping.
-func (special SpecialCase) ToLower(rune int) int {
-	r := to(LowerCase, rune, []CaseRange(special))
-	if r == rune {
-		r = ToLower(rune)
+func (special SpecialCase) ToLower(r rune) rune {
+	r1 := to(LowerCase, r, []CaseRange(special))
+	if r1 == r {
+		r1 = ToLower(r)
 	}
-	return r
+	return r1
 }
 
 // caseOrbit is defined in tables.go as []foldPair.  Right now all the
@@ -300,27 +300,27 @@ type foldPair struct {
 //
 //	SimpleFold('1') = '1'
 //
-func SimpleFold(rune int) int {
+func SimpleFold(r rune) rune {
 	// Consult caseOrbit table for special cases.
 	lo := 0
 	hi := len(caseOrbit)
 	for lo < hi {
 		m := lo + (hi-lo)/2
-		if int(caseOrbit[m].From) < rune {
+		if rune(caseOrbit[m].From) < r {
 			lo = m + 1
 		} else {
 			hi = m
 		}
 	}
-	if lo < len(caseOrbit) && int(caseOrbit[lo].From) == rune {
-		return int(caseOrbit[lo].To)
+	if lo < len(caseOrbit) && rune(caseOrbit[lo].From) == r {
+		return rune(caseOrbit[lo].To)
 	}
 
 	// No folding specified.  This is a one- or two-element
 	// equivalence class containing rune and ToLower(rune)
 	// and ToUpper(rune) if they are different from rune.
-	if l := ToLower(rune); l != rune {
+	if l := ToLower(r); l != r {
 		return l
 	}
-	return ToUpper(rune)
+	return ToUpper(r)
 }
diff --git a/libgo/go/unicode/letter_test.go b/libgo/go/unicode/letter_test.go
index 8d2665a..2d80562 100644
--- a/libgo/go/unicode/letter_test.go
+++ b/libgo/go/unicode/letter_test.go
@@ -9,7 +9,7 @@ import (
 	. "unicode"
 )
 
-var upperTest = []int{
+var upperTest = []rune{
 	0x41,
 	0xc0,
 	0xd8,
@@ -33,7 +33,7 @@ var upperTest = []int{
 	0x1d7ca,
 }
 
-var notupperTest = []int{
+var notupperTest = []rune{
 	0x40,
 	0x5b,
 	0x61,
@@ -46,7 +46,7 @@ var notupperTest = []int{
 	0x10000,
 }
 
-var letterTest = []int{
+var letterTest = []rune{
 	0x41,
 	0x61,
 	0xaa,
@@ -82,7 +82,7 @@ var letterTest = []int{
 	0x2fa1d,
 }
 
-var notletterTest = []int{
+var notletterTest = []rune{
 	0x20,
 	0x35,
 	0x375,
@@ -94,7 +94,7 @@ var notletterTest = []int{
 }
 
 // Contains all the special cased Latin-1 chars.
-var spaceTest = []int{
+var spaceTest = []rune{
 	0x09,
 	0x0a,
 	0x0b,
@@ -108,7 +108,8 @@ var spaceTest = []int{
 }
 
 type caseT struct {
-	cas, in, out int
+	cas     int
+	in, out rune
 }
 
 var caseTest = []caseT{
@@ -327,7 +328,7 @@ func TestIsSpace(t *testing.T) {
 // Check that the optimizations for IsLetter etc. agree with the tables.
 // We only need to check the Latin-1 range.
 func TestLetterOptimizations(t *testing.T) {
-	for i := 0; i <= MaxLatin1; i++ {
+	for i := rune(0); i <= MaxLatin1; i++ {
 		if Is(Letter, i) != IsLetter(i) {
 			t.Errorf("IsLetter(U+%04X) disagrees with Is(Letter)", i)
 		}
@@ -356,8 +357,8 @@ func TestLetterOptimizations(t *testing.T) {
 }
 
 func TestTurkishCase(t *testing.T) {
-	lower := []int("abcçdefgğhıijklmnoöprsştuüvyz")
-	upper := []int("ABCÇDEFGĞHIİJKLMNOÖPRSŞTUÜVYZ")
+	lower := []rune("abcçdefgğhıijklmnoöprsştuüvyz")
+	upper := []rune("ABCÇDEFGĞHIİJKLMNOÖPRSŞTUÜVYZ")
 	for i, l := range lower {
 		u := upper[i]
 		if TurkishCase.ToLower(l) != l {
@@ -416,13 +417,13 @@ var simpleFoldTests = []string{
 
 func TestSimpleFold(t *testing.T) {
 	for _, tt := range simpleFoldTests {
-		cycle := []int(tt)
-		rune := cycle[len(cycle)-1]
+		cycle := []rune(tt)
+		r := cycle[len(cycle)-1]
 		for _, out := range cycle {
-			if r := SimpleFold(rune); r != out {
-				t.Errorf("SimpleFold(%#U) = %#U, want %#U", rune, r, out)
+			if r := SimpleFold(r); r != out {
+				t.Errorf("SimpleFold(%#U) = %#U, want %#U", r, r, out)
 			}
-			rune = out
+			r = out
 		}
 	}
 }
diff --git a/libgo/go/unicode/script_test.go b/libgo/go/unicode/script_test.go
index dfd636d..1c5b801 100644
--- a/libgo/go/unicode/script_test.go
+++ b/libgo/go/unicode/script_test.go
@@ -10,7 +10,7 @@ import (
 )
 
 type T struct {
-	rune   int
+	rune   rune
 	script string
 }
 
diff --git a/libgo/go/utf16/utf16.go b/libgo/go/utf16/utf16.go
index 372e38a..2b2eb28 100644
--- a/libgo/go/utf16/utf16.go
+++ b/libgo/go/utf16/utf16.go
@@ -20,16 +20,16 @@ const (
 
 // IsSurrogate returns true if the specified Unicode code point
 // can appear in a surrogate pair.
-func IsSurrogate(rune int) bool {
-	return surr1 <= rune && rune < surr3
+func IsSurrogate(r rune) bool {
+	return surr1 <= r && r < surr3
 }
 
 // DecodeRune returns the UTF-16 decoding of a surrogate pair.
 // If the pair is not a valid UTF-16 surrogate pair, DecodeRune returns
 // the Unicode replacement code point U+FFFD.
-func DecodeRune(r1, r2 int) int {
+func DecodeRune(r1, r2 rune) rune {
 	if surr1 <= r1 && r1 < surr2 && surr2 <= r2 && r2 < surr3 {
-		return (int(r1)-surr1)<<10 | (int(r2) - surr2) + 0x10000
+		return (rune(r1)-surr1)<<10 | (rune(r2) - surr2) + 0x10000
 	}
 	return unicode.ReplacementChar
 }
@@ -37,16 +37,16 @@ func DecodeRune(r1, r2 int) int {
 // EncodeRune returns the UTF-16 surrogate pair r1, r2 for the given rune.
 // If the rune is not a valid Unicode code point or does not need encoding,
 // EncodeRune returns U+FFFD, U+FFFD.
-func EncodeRune(rune int) (r1, r2 int) {
-	if rune < surrSelf || rune > unicode.MaxRune || IsSurrogate(rune) {
+func EncodeRune(r rune) (r1, r2 rune) {
+	if r < surrSelf || r > unicode.MaxRune || IsSurrogate(r) {
 		return unicode.ReplacementChar, unicode.ReplacementChar
 	}
-	rune -= surrSelf
-	return surr1 + (rune>>10)&0x3ff, surr2 + rune&0x3ff
+	r -= surrSelf
+	return surr1 + (r>>10)&0x3ff, surr2 + r&0x3ff
 }
 
 // Encode returns the UTF-16 encoding of the Unicode code point sequence s.
-func Encode(s []int) []uint16 {
+func Encode(s []rune) []uint16 {
 	n := len(s)
 	for _, v := range s {
 		if v >= surrSelf {
@@ -76,15 +76,15 @@ func Encode(s []int) []uint16 {
 
 // Decode returns the Unicode code point sequence represented
 // by the UTF-16 encoding s.
-func Decode(s []uint16) []int {
-	a := make([]int, len(s))
+func Decode(s []uint16) []rune {
+	a := make([]rune, len(s))
 	n := 0
 	for i := 0; i < len(s); i++ {
 		switch r := s[i]; {
 		case surr1 <= r && r < surr2 && i+1 < len(s) &&
 			surr2 <= s[i+1] && s[i+1] < surr3:
 			// valid surrogate sequence
-			a[n] = DecodeRune(int(r), int(s[i+1]))
+			a[n] = DecodeRune(rune(r), rune(s[i+1]))
 			i++
 			n++
 		case surr1 <= r && r < surr3:
@@ -93,7 +93,7 @@ func Decode(s []uint16) []int {
 			n++
 		default:
 			// normal rune
-			a[n] = int(r)
+			a[n] = rune(r)
 			n++
 		}
 	}
diff --git a/libgo/go/utf16/utf16_test.go b/libgo/go/utf16/utf16_test.go
index 2b9fb3d..7ea290a 100644
--- a/libgo/go/utf16/utf16_test.go
+++ b/libgo/go/utf16/utf16_test.go
@@ -5,7 +5,6 @@
 package utf16_test
 
 import (
-	"fmt"
 	"reflect"
 	"testing"
 	"unicode"
@@ -13,15 +12,15 @@ import (
 )
 
 type encodeTest struct {
-	in  []int
+	in  []rune
 	out []uint16
 }
 
 var encodeTests = []encodeTest{
-	{[]int{1, 2, 3, 4}, []uint16{1, 2, 3, 4}},
-	{[]int{0xffff, 0x10000, 0x10001, 0x12345, 0x10ffff},
+	{[]rune{1, 2, 3, 4}, []uint16{1, 2, 3, 4}},
+	{[]rune{0xffff, 0x10000, 0x10001, 0x12345, 0x10ffff},
 		[]uint16{0xffff, 0xd800, 0xdc00, 0xd800, 0xdc01, 0xd808, 0xdf45, 0xdbff, 0xdfff}},
-	{[]int{'a', 'b', 0xd7ff, 0xd800, 0xdfff, 0xe000, 0x110000, -1},
+	{[]rune{'a', 'b', 0xd7ff, 0xd800, 0xdfff, 0xe000, 0x110000, -1},
 		[]uint16{'a', 'b', 0xd7ff, 0xfffd, 0xfffd, 0xe000, 0xfffd, 0xfffd}},
 }
 
@@ -29,7 +28,7 @@ func TestEncode(t *testing.T) {
 	for _, tt := range encodeTests {
 		out := Encode(tt.in)
 		if !reflect.DeepEqual(out, tt.out) {
-			t.Errorf("Encode(%v) = %v; want %v", hex(tt.in), hex16(out), hex16(tt.out))
+			t.Errorf("Encode(%x) = %x; want %x", tt.in, out, tt.out)
 		}
 	}
 }
@@ -53,7 +52,7 @@ func TestEncodeRune(t *testing.T) {
 					t.Errorf("#%d: ran out of tt.out", i)
 					break
 				}
-				if r1 != int(tt.out[j]) || r2 != int(tt.out[j+1]) {
+				if r1 != rune(tt.out[j]) || r2 != rune(tt.out[j+1]) {
 					t.Errorf("EncodeRune(%#x) = %#x, %#x; want %#x, %#x", r, r1, r2, tt.out[j], tt.out[j+1])
 				}
 				j += 2
@@ -71,48 +70,22 @@ func TestEncodeRune(t *testing.T) {
 
 type decodeTest struct {
 	in  []uint16
-	out []int
+	out []rune
 }
 
 var decodeTests = []decodeTest{
-	{[]uint16{1, 2, 3, 4}, []int{1, 2, 3, 4}},
+	{[]uint16{1, 2, 3, 4}, []rune{1, 2, 3, 4}},
 	{[]uint16{0xffff, 0xd800, 0xdc00, 0xd800, 0xdc01, 0xd808, 0xdf45, 0xdbff, 0xdfff},
-		[]int{0xffff, 0x10000, 0x10001, 0x12345, 0x10ffff}},
-	{[]uint16{0xd800, 'a'}, []int{0xfffd, 'a'}},
-	{[]uint16{0xdfff}, []int{0xfffd}},
+		[]rune{0xffff, 0x10000, 0x10001, 0x12345, 0x10ffff}},
+	{[]uint16{0xd800, 'a'}, []rune{0xfffd, 'a'}},
+	{[]uint16{0xdfff}, []rune{0xfffd}},
 }
 
 func TestDecode(t *testing.T) {
 	for _, tt := range decodeTests {
 		out := Decode(tt.in)
 		if !reflect.DeepEqual(out, tt.out) {
-			t.Errorf("Decode(%v) = %v; want %v", hex16(tt.in), hex(out), hex(tt.out))
+			t.Errorf("Decode(%x) = %x; want %x", tt.in, out, tt.out)
 		}
 	}
 }
-
-type hex []int
-
-func (h hex) Format(f fmt.State, c int) {
-	fmt.Fprint(f, "[")
-	for i, v := range h {
-		if i > 0 {
-			fmt.Fprint(f, " ")
-		}
-		fmt.Fprintf(f, "%x", v)
-	}
-	fmt.Fprint(f, "]")
-}
-
-type hex16 []uint16
-
-func (h hex16) Format(f fmt.State, c int) {
-	fmt.Fprint(f, "[")
-	for i, v := range h {
-		if i > 0 {
-			fmt.Fprint(f, " ")
-		}
-		fmt.Fprintf(f, "%x", v)
-	}
-	fmt.Fprint(f, "]")
-}
diff --git a/libgo/go/utf8/string.go b/libgo/go/utf8/string.go
index 83b56b9..b333479 100644
--- a/libgo/go/utf8/string.go
+++ b/libgo/go/utf8/string.go
@@ -101,10 +101,10 @@ func (s *String) Slice(i, j int) string {
 
 // At returns the rune with index i in the String.  The sequence of runes is the same
 // as iterating over the contents with a "for range" clause.
-func (s *String) At(i int) int {
+func (s *String) At(i int) rune {
 	// ASCII is easy.  Let the compiler catch the indexing error if there is one.
 	if i < s.nonASCII {
-		return int(s.str[i])
+		return rune(s.str[i])
 	}
 
 	// Now we do need to know the index is valid.
@@ -112,35 +112,35 @@ func (s *String) At(i int) int {
 		panic(outOfRange)
 	}
 
-	var rune int
+	var r rune
 
 	// Five easy common cases: within 1 spot of bytePos/runePos, or the beginning, or the end.
 	// With these cases, all scans from beginning or end work in O(1) time per rune.
 	switch {
 
 	case i == s.runePos-1: // backing up one rune
-		rune, s.width = DecodeLastRuneInString(s.str[0:s.bytePos])
+		r, s.width = DecodeLastRuneInString(s.str[0:s.bytePos])
 		s.runePos = i
 		s.bytePos -= s.width
-		return rune
+		return r
 	case i == s.runePos+1: // moving ahead one rune
 		s.runePos = i
 		s.bytePos += s.width
 		fallthrough
 	case i == s.runePos:
-		rune, s.width = DecodeRuneInString(s.str[s.bytePos:])
-		return rune
+		r, s.width = DecodeRuneInString(s.str[s.bytePos:])
+		return r
 	case i == 0: // start of string
-		rune, s.width = DecodeRuneInString(s.str)
+		r, s.width = DecodeRuneInString(s.str)
 		s.runePos = 0
 		s.bytePos = 0
-		return rune
+		return r
 
 	case i == s.numRunes-1: // last rune in string
-		rune, s.width = DecodeLastRuneInString(s.str)
+		r, s.width = DecodeLastRuneInString(s.str)
 		s.runePos = i
 		s.bytePos = len(s.str) - s.width
-		return rune
+		return r
 	}
 
 	// We need to do a linear scan.  There are three places to start from:
@@ -173,7 +173,7 @@ func (s *String) At(i int) int {
 	if forward {
 		// TODO: Is it much faster to use a range loop for this scan?
 		for {
-			rune, s.width = DecodeRuneInString(s.str[s.bytePos:])
+			r, s.width = DecodeRuneInString(s.str[s.bytePos:])
 			if s.runePos == i {
 				break
 			}
@@ -182,7 +182,7 @@ func (s *String) At(i int) int {
 		}
 	} else {
 		for {
-			rune, s.width = DecodeLastRuneInString(s.str[0:s.bytePos])
+			r, s.width = DecodeLastRuneInString(s.str[0:s.bytePos])
 			s.runePos--
 			s.bytePos -= s.width
 			if s.runePos == i {
@@ -190,7 +190,7 @@ func (s *String) At(i int) int {
 			}
 		}
 	}
-	return rune
+	return r
 }
 
 // We want the panic in At(i) to satisfy os.Error, because that's what
diff --git a/libgo/go/utf8/string_test.go b/libgo/go/utf8/string_test.go
index f376b62..920d2a0 100644
--- a/libgo/go/utf8/string_test.go
+++ b/libgo/go/utf8/string_test.go
@@ -12,7 +12,7 @@ import (
 
 func TestScanForwards(t *testing.T) {
 	for _, s := range testStrings {
-		runes := []int(s)
+		runes := []rune(s)
 		str := NewString(s)
 		if str.RuneCount() != len(runes) {
 			t.Errorf("%s: expected %d runes; got %d", s, len(runes), str.RuneCount())
@@ -29,7 +29,7 @@ func TestScanForwards(t *testing.T) {
 
 func TestScanBackwards(t *testing.T) {
 	for _, s := range testStrings {
-		runes := []int(s)
+		runes := []rune(s)
 		str := NewString(s)
 		if str.RuneCount() != len(runes) {
 			t.Errorf("%s: expected %d runes; got %d", s, len(runes), str.RuneCount())
@@ -57,7 +57,7 @@ func TestRandomAccess(t *testing.T) {
 		if len(s) == 0 {
 			continue
 		}
-		runes := []int(s)
+		runes := []rune(s)
 		str := NewString(s)
 		if str.RuneCount() != len(runes) {
 			t.Errorf("%s: expected %d runes; got %d", s, len(runes), str.RuneCount())
@@ -79,7 +79,7 @@ func TestRandomSliceAccess(t *testing.T) {
 		if len(s) == 0 || s[0] == '\x80' { // the bad-UTF-8 string fools this simple test
 			continue
 		}
-		runes := []int(s)
+		runes := []rune(s)
 		str := NewString(s)
 		if str.RuneCount() != len(runes) {
 			t.Errorf("%s: expected %d runes; got %d", s, len(runes), str.RuneCount())
diff --git a/libgo/go/utf8/utf8.go b/libgo/go/utf8/utf8.go
index 3cd919d..a5f9983 100644
--- a/libgo/go/utf8/utf8.go
+++ b/libgo/go/utf8/utf8.go
@@ -34,7 +34,7 @@ const (
 	rune4Max = 1<<21 - 1
 )
 
-func decodeRuneInternal(p []byte) (rune, size int, short bool) {
+func decodeRuneInternal(p []byte) (r rune, size int, short bool) {
 	n := len(p)
 	if n < 1 {
 		return RuneError, 0, true
@@ -43,7 +43,7 @@ func decodeRuneInternal(p []byte) (rune, size int, short bool) {
 
 	// 1-byte, 7-bit sequence?
 	if c0 < tx {
-		return int(c0), 1, false
+		return rune(c0), 1, false
 	}
 
 	// unexpected continuation byte?
@@ -62,11 +62,11 @@ func decodeRuneInternal(p []byte) (rune, size int, short bool) {
 
 	// 2-byte, 11-bit sequence?
 	if c0 < t3 {
-		rune = int(c0&mask2)<<6 | int(c1&maskx)
-		if rune <= rune1Max {
+		r = rune(c0&mask2)<<6 | rune(c1&maskx)
+		if r <= rune1Max {
 			return RuneError, 1, false
 		}
-		return rune, 2, false
+		return r, 2, false
 	}
 
 	// need second continuation byte
@@ -80,11 +80,11 @@ func decodeRuneInternal(p []byte) (rune, size int, short bool) {
 
 	// 3-byte, 16-bit sequence?
 	if c0 < t4 {
-		rune = int(c0&mask3)<<12 | int(c1&maskx)<<6 | int(c2&maskx)
-		if rune <= rune2Max {
+		r = rune(c0&mask3)<<12 | rune(c1&maskx)<<6 | rune(c2&maskx)
+		if r <= rune2Max {
 			return RuneError, 1, false
 		}
-		return rune, 3, false
+		return r, 3, false
 	}
 
 	// need third continuation byte
@@ -98,18 +98,18 @@ func decodeRuneInternal(p []byte) (rune, size int, short bool) {
 
 	// 4-byte, 21-bit sequence?
 	if c0 < t5 {
-		rune = int(c0&mask4)<<18 | int(c1&maskx)<<12 | int(c2&maskx)<<6 | int(c3&maskx)
-		if rune <= rune3Max {
+		r = rune(c0&mask4)<<18 | rune(c1&maskx)<<12 | rune(c2&maskx)<<6 | rune(c3&maskx)
+		if r <= rune3Max {
 			return RuneError, 1, false
 		}
-		return rune, 4, false
+		return r, 4, false
 	}
 
 	// error
 	return RuneError, 1, false
 }
 
-func decodeRuneInStringInternal(s string) (rune, size int, short bool) {
+func decodeRuneInStringInternal(s string) (r rune, size int, short bool) {
 	n := len(s)
 	if n < 1 {
 		return RuneError, 0, true
@@ -118,7 +118,7 @@ func decodeRuneInStringInternal(s string) (rune, size int, short bool) {
 
 	// 1-byte, 7-bit sequence?
 	if c0 < tx {
-		return int(c0), 1, false
+		return rune(c0), 1, false
 	}
 
 	// unexpected continuation byte?
@@ -137,11 +137,11 @@ func decodeRuneInStringInternal(s string) (rune, size int, short bool) {
 
 	// 2-byte, 11-bit sequence?
 	if c0 < t3 {
-		rune = int(c0&mask2)<<6 | int(c1&maskx)
-		if rune <= rune1Max {
+		r = rune(c0&mask2)<<6 | rune(c1&maskx)
+		if r <= rune1Max {
 			return RuneError, 1, false
 		}
-		return rune, 2, false
+		return r, 2, false
 	}
 
 	// need second continuation byte
@@ -155,11 +155,11 @@ func decodeRuneInStringInternal(s string) (rune, size int, short bool) {
 
 	// 3-byte, 16-bit sequence?
 	if c0 < t4 {
-		rune = int(c0&mask3)<<12 | int(c1&maskx)<<6 | int(c2&maskx)
-		if rune <= rune2Max {
+		r = rune(c0&mask3)<<12 | rune(c1&maskx)<<6 | rune(c2&maskx)
+		if r <= rune2Max {
 			return RuneError, 1, false
 		}
-		return rune, 3, false
+		return r, 3, false
 	}
 
 	// need third continuation byte
@@ -173,11 +173,11 @@ func decodeRuneInStringInternal(s string) (rune, size int, short bool) {
 
 	// 4-byte, 21-bit sequence?
 	if c0 < t5 {
-		rune = int(c0&mask4)<<18 | int(c1&maskx)<<12 | int(c2&maskx)<<6 | int(c3&maskx)
-		if rune <= rune3Max {
+		r = rune(c0&mask4)<<18 | rune(c1&maskx)<<12 | rune(c2&maskx)<<6 | rune(c3&maskx)
+		if r <= rune3Max {
 			return RuneError, 1, false
 		}
-		return rune, 4, false
+		return r, 4, false
 	}
 
 	// error
@@ -198,28 +198,28 @@ func FullRuneInString(s string) bool {
 }
 
 // DecodeRune unpacks the first UTF-8 encoding in p and returns the rune and its width in bytes.
-func DecodeRune(p []byte) (rune, size int) {
-	rune, size, _ = decodeRuneInternal(p)
+func DecodeRune(p []byte) (r rune, size int) {
+	r, size, _ = decodeRuneInternal(p)
 	return
 }
 
 // DecodeRuneInString is like DecodeRune but its input is a string.
-func DecodeRuneInString(s string) (rune, size int) {
-	rune, size, _ = decodeRuneInStringInternal(s)
+func DecodeRuneInString(s string) (r rune, size int) {
+	r, size, _ = decodeRuneInStringInternal(s)
 	return
 }
 
 // DecodeLastRune unpacks the last UTF-8 encoding in p
 // and returns the rune and its width in bytes.
-func DecodeLastRune(p []byte) (rune, size int) {
+func DecodeLastRune(p []byte) (r rune, size int) {
 	end := len(p)
 	if end == 0 {
 		return RuneError, 0
 	}
 	start := end - 1
-	rune = int(p[start])
-	if rune < RuneSelf {
-		return rune, 1
+	r = rune(p[start])
+	if r < RuneSelf {
+		return r, 1
 	}
 	// guard against O(n^2) behavior when traversing
 	// backwards through strings with long sequences of
@@ -236,23 +236,23 @@ func DecodeLastRune(p []byte) (rune, size int) {
 	if start < 0 {
 		start = 0
 	}
-	rune, size = DecodeRune(p[start:end])
+	r, size = DecodeRune(p[start:end])
 	if start+size != end {
 		return RuneError, 1
 	}
-	return rune, size
+	return r, size
 }
 
 // DecodeLastRuneInString is like DecodeLastRune but its input is a string.
-func DecodeLastRuneInString(s string) (rune, size int) {
+func DecodeLastRuneInString(s string) (r rune, size int) {
 	end := len(s)
 	if end == 0 {
 		return RuneError, 0
 	}
 	start := end - 1
-	rune = int(s[start])
-	if rune < RuneSelf {
-		return rune, 1
+	r = rune(s[start])
+	if r < RuneSelf {
+		return r, 1
 	}
 	// guard against O(n^2) behavior when traversing
 	// backwards through strings with long sequences of
@@ -269,23 +269,23 @@ func DecodeLastRuneInString(s string) (rune, size int) {
 	if start < 0 {
 		start = 0
 	}
-	rune, size = DecodeRuneInString(s[start:end])
+	r, size = DecodeRuneInString(s[start:end])
 	if start+size != end {
 		return RuneError, 1
 	}
-	return rune, size
+	return r, size
 }
 
 // RuneLen returns the number of bytes required to encode the rune.
-func RuneLen(rune int) int {
+func RuneLen(r rune) int {
 	switch {
-	case rune <= rune1Max:
+	case r <= rune1Max:
 		return 1
-	case rune <= rune2Max:
+	case r <= rune2Max:
 		return 2
-	case rune <= rune3Max:
+	case r <= rune3Max:
 		return 3
-	case rune <= rune4Max:
+	case r <= rune4Max:
 		return 4
 	}
 	return -1
@@ -293,26 +293,24 @@ func RuneLen(rune int) int {
 
 // EncodeRune writes into p (which must be large enough) the UTF-8 encoding of the rune.
 // It returns the number of bytes written.
-func EncodeRune(p []byte, rune int) int {
+func EncodeRune(p []byte, r rune) int {
 	// Negative values are erroneous.  Making it unsigned addresses the problem.
-	r := uint(rune)
-
-	if r <= rune1Max {
+	if uint32(r) <= rune1Max {
 		p[0] = byte(r)
 		return 1
 	}
 
-	if r <= rune2Max {
+	if uint32(r) <= rune2Max {
 		p[0] = t2 | byte(r>>6)
 		p[1] = tx | byte(r)&maskx
 		return 2
 	}
 
-	if r > unicode.MaxRune {
+	if uint32(r) > unicode.MaxRune {
 		r = RuneError
 	}
 
-	if r <= rune3Max {
+	if uint32(r) <= rune3Max {
 		p[0] = t3 | byte(r>>12)
 		p[1] = tx | byte(r>>6)&maskx
 		p[2] = tx | byte(r)&maskx
diff --git a/libgo/go/utf8/utf8_test.go b/libgo/go/utf8/utf8_test.go
index 6cbbebc..857bcf6 100644
--- a/libgo/go/utf8/utf8_test.go
+++ b/libgo/go/utf8/utf8_test.go
@@ -11,8 +11,8 @@ import (
 )
 
 type Utf8Map struct {
-	rune int
-	str  string
+	r   rune
+	str string
 }
 
 var utf8map = []Utf8Map{
@@ -58,11 +58,11 @@ func TestFullRune(t *testing.T) {
 		m := utf8map[i]
 		b := []byte(m.str)
 		if !FullRune(b) {
-			t.Errorf("FullRune(%q) (%U) = false, want true", b, m.rune)
+			t.Errorf("FullRune(%q) (%U) = false, want true", b, m.r)
 		}
 		s := m.str
 		if !FullRuneInString(s) {
-			t.Errorf("FullRuneInString(%q) (%U) = false, want true", s, m.rune)
+			t.Errorf("FullRuneInString(%q) (%U) = false, want true", s, m.r)
 		}
 		b1 := b[0 : len(b)-1]
 		if FullRune(b1) {
@@ -80,10 +80,10 @@ func TestEncodeRune(t *testing.T) {
 		m := utf8map[i]
 		b := []byte(m.str)
 		var buf [10]byte
-		n := EncodeRune(buf[0:], m.rune)
+		n := EncodeRune(buf[0:], m.r)
 		b1 := buf[0:n]
 		if !bytes.Equal(b, b1) {
-			t.Errorf("EncodeRune(%#04x) = %q want %q", m.rune, b1, b)
+			t.Errorf("EncodeRune(%#04x) = %q want %q", m.r, b1, b)
 		}
 	}
 }
@@ -92,25 +92,25 @@ func TestDecodeRune(t *testing.T) {
 	for i := 0; i < len(utf8map); i++ {
 		m := utf8map[i]
 		b := []byte(m.str)
-		rune, size := DecodeRune(b)
-		if rune != m.rune || size != len(b) {
-			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", b, rune, size, m.rune, len(b))
+		r, size := DecodeRune(b)
+		if r != m.r || size != len(b) {
+			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", b, r, size, m.r, len(b))
 		}
 		s := m.str
-		rune, size = DecodeRuneInString(s)
-		if rune != m.rune || size != len(b) {
-			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", s, rune, size, m.rune, len(b))
+		r, size = DecodeRuneInString(s)
+		if r != m.r || size != len(b) {
+			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", s, r, size, m.r, len(b))
 		}
 
 		// there's an extra byte that bytes left behind - make sure trailing byte works
-		rune, size = DecodeRune(b[0:cap(b)])
-		if rune != m.rune || size != len(b) {
-			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", b, rune, size, m.rune, len(b))
+		r, size = DecodeRune(b[0:cap(b)])
+		if r != m.r || size != len(b) {
+			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", b, r, size, m.r, len(b))
 		}
 		s = m.str + "\x00"
-		rune, size = DecodeRuneInString(s)
-		if rune != m.rune || size != len(b) {
-			t.Errorf("DecodeRuneInString(%q) = %#04x, %d want %#04x, %d", s, rune, size, m.rune, len(b))
+		r, size = DecodeRuneInString(s)
+		if r != m.r || size != len(b) {
+			t.Errorf("DecodeRuneInString(%q) = %#04x, %d want %#04x, %d", s, r, size, m.r, len(b))
 		}
 
 		// make sure missing bytes fail
@@ -118,14 +118,14 @@ func TestDecodeRune(t *testing.T) {
 		if wantsize >= len(b) {
 			wantsize = 0
 		}
-		rune, size = DecodeRune(b[0 : len(b)-1])
-		if rune != RuneError || size != wantsize {
-			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", b[0:len(b)-1], rune, size, RuneError, wantsize)
+		r, size = DecodeRune(b[0 : len(b)-1])
+		if r != RuneError || size != wantsize {
+			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", b[0:len(b)-1], r, size, RuneError, wantsize)
 		}
 		s = m.str[0 : len(m.str)-1]
-		rune, size = DecodeRuneInString(s)
-		if rune != RuneError || size != wantsize {
-			t.Errorf("DecodeRuneInString(%q) = %#04x, %d want %#04x, %d", s, rune, size, RuneError, wantsize)
+		r, size = DecodeRuneInString(s)
+		if r != RuneError || size != wantsize {
+			t.Errorf("DecodeRuneInString(%q) = %#04x, %d want %#04x, %d", s, r, size, RuneError, wantsize)
 		}
 
 		// make sure bad sequences fail
@@ -134,14 +134,14 @@ func TestDecodeRune(t *testing.T) {
 		} else {
 			b[len(b)-1] = 0x7F
 		}
-		rune, size = DecodeRune(b)
-		if rune != RuneError || size != 1 {
-			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", b, rune, size, RuneError, 1)
+		r, size = DecodeRune(b)
+		if r != RuneError || size != 1 {
+			t.Errorf("DecodeRune(%q) = %#04x, %d want %#04x, %d", b, r, size, RuneError, 1)
 		}
 		s = string(b)
-		rune, size = DecodeRune(b)
-		if rune != RuneError || size != 1 {
-			t.Errorf("DecodeRuneInString(%q) = %#04x, %d want %#04x, %d", s, rune, size, RuneError, 1)
+		r, size = DecodeRune(b)
+		if r != RuneError || size != 1 {
+			t.Errorf("DecodeRuneInString(%q) = %#04x, %d want %#04x, %d", s, r, size, RuneError, 1)
 		}
 
 	}
@@ -164,7 +164,7 @@ func TestSequencing(t *testing.T) {
 // it's good to verify
 func TestIntConversion(t *testing.T) {
 	for _, ts := range testStrings {
-		runes := []int(ts)
+		runes := []rune(ts)
 		if RuneCountInString(ts) != len(runes) {
 			t.Errorf("%q: expected %d runes; got %d", ts, len(runes), RuneCountInString(ts))
 			break
@@ -182,7 +182,7 @@ func TestIntConversion(t *testing.T) {
 func testSequence(t *testing.T, s string) {
 	type info struct {
 		index int
-		rune  int
+		r     rune
 	}
 	index := make([]info, len(s))
 	b := []byte(s)
@@ -195,14 +195,14 @@ func testSequence(t *testing.T, s string) {
 		}
 		index[j] = info{i, r}
 		j++
-		rune1, size1 := DecodeRune(b[i:])
-		if r != rune1 {
-			t.Errorf("DecodeRune(%q) = %#04x, want %#04x", s[i:], rune1, r)
+		r1, size1 := DecodeRune(b[i:])
+		if r != r1 {
+			t.Errorf("DecodeRune(%q) = %#04x, want %#04x", s[i:], r1, r)
 			return
 		}
-		rune2, size2 := DecodeRuneInString(s[i:])
-		if r != rune2 {
-			t.Errorf("DecodeRuneInString(%q) = %#04x, want %#04x", s[i:], rune2, r)
+		r2, size2 := DecodeRuneInString(s[i:])
+		if r != r2 {
+			t.Errorf("DecodeRuneInString(%q) = %#04x, want %#04x", s[i:], r2, r)
 			return
 		}
 		if size1 != size2 {
@@ -213,18 +213,18 @@ func testSequence(t *testing.T, s string) {
 	}
 	j--
 	for si = len(s); si > 0; {
-		rune1, size1 := DecodeLastRune(b[0:si])
-		rune2, size2 := DecodeLastRuneInString(s[0:si])
+		r1, size1 := DecodeLastRune(b[0:si])
+		r2, size2 := DecodeLastRuneInString(s[0:si])
 		if size1 != size2 {
 			t.Errorf("DecodeLastRune/DecodeLastRuneInString(%q, %d) size mismatch %d/%d", s, si, size1, size2)
 			return
 		}
-		if rune1 != index[j].rune {
-			t.Errorf("DecodeLastRune(%q, %d) = %#04x, want %#04x", s, si, rune1, index[j].rune)
+		if r1 != index[j].r {
+			t.Errorf("DecodeLastRune(%q, %d) = %#04x, want %#04x", s, si, r1, index[j].r)
 			return
 		}
-		if rune2 != index[j].rune {
-			t.Errorf("DecodeLastRuneInString(%q, %d) = %#04x, want %#04x", s, si, rune2, index[j].rune)
+		if r2 != index[j].r {
+			t.Errorf("DecodeLastRuneInString(%q, %d) = %#04x, want %#04x", s, si, r2, index[j].r)
 			return
 		}
 		si -= size1
diff --git a/libgo/go/xml/marshal_test.go b/libgo/go/xml/marshal_test.go
index ad3aa97..eb358d5 100644
--- a/libgo/go/xml/marshal_test.go
+++ b/libgo/go/xml/marshal_test.go
@@ -8,10 +8,10 @@ import (
 	"reflect"
 	"testing"
 
-	"os"
 	"bytes"
-	"strings"
+	"os"
 	"strconv"
+	"strings"
 )
 
 type DriveType int
@@ -314,27 +314,27 @@ func TestMarshal(t *testing.T) {
 }
 
 var marshalErrorTests = []struct {
-	Value      interface{}
-	ExpectErr  string
-	ExpectKind reflect.Kind
+	Value interface{}
+	Err   string
+	Kind  reflect.Kind
 }{
 	{
-		Value:      make(chan bool),
-		ExpectErr:  "xml: unsupported type: chan bool",
-		ExpectKind: reflect.Chan,
+		Value: make(chan bool),
+		Err:   "xml: unsupported type: chan bool",
+		Kind:  reflect.Chan,
 	},
 	{
 		Value: map[string]string{
 			"question": "What do you get when you multiply six by nine?",
 			"answer":   "42",
 		},
-		ExpectErr:  "xml: unsupported type: map[string] string",
-		ExpectKind: reflect.Map,
+		Err:  "xml: unsupported type: map[string] string",
+		Kind: reflect.Map,
 	},
 	{
-		Value:      map[*Ship]bool{nil: false},
-		ExpectErr:  "xml: unsupported type: map[*xml.Ship] bool",
-		ExpectKind: reflect.Map,
+		Value: map[*Ship]bool{nil: false},
+		Err:   "xml: unsupported type: map[*xml.Ship] bool",
+		Kind:  reflect.Map,
 	},
 }
 
@@ -342,14 +342,11 @@ func TestMarshalErrors(t *testing.T) {
 	for idx, test := range marshalErrorTests {
 		buf := bytes.NewBuffer(nil)
 		err := Marshal(buf, test.Value)
-		if got, want := err, test.ExpectErr; got == nil {
-			t.Errorf("#%d: want error %s", idx, want)
-			continue
-		} else if got.String() != want {
-			t.Errorf("#%d: marshal(%#v) = [error] %q, want %q", idx, test.Value, got, want)
+		if err == nil || err.String() != test.Err {
+			t.Errorf("#%d: marshal(%#v) = [error] %q, want %q", idx, test.Value, err, test.Err)
 		}
-		if got, want := err.(*UnsupportedTypeError).Type.Kind(), test.ExpectKind; got != want {
-			t.Errorf("#%d: marshal(%#v) = [error kind] %s, want %s", idx, test.Value, got, want)
+		if kind := err.(*UnsupportedTypeError).Type.Kind(); kind != test.Kind {
+			t.Errorf("#%d: marshal(%#v) = [error kind] %s, want %s", idx, test.Value, kind, test.Kind)
 		}
 	}
 }
diff --git a/libgo/go/xml/read.go b/libgo/go/xml/read.go
index f64e130..1fe20ac 100644
--- a/libgo/go/xml/read.go
+++ b/libgo/go/xml/read.go
@@ -206,7 +206,7 @@ func fieldName(original string) string {
 	}
 
 	return strings.Map(
-		func(x int) int {
+		func(x rune) rune {
 			if x == '_' || unicode.IsDigit(x) || unicode.IsLetter(x) {
 				return unicode.ToLower(x)
 			}
diff --git a/libgo/go/xml/xml.go b/libgo/go/xml/xml.go
index 85c24bc..bc03c8e 100644
--- a/libgo/go/xml/xml.go
+++ b/libgo/go/xml/xml.go
@@ -960,13 +960,13 @@ Input:
 // Decide whether the given rune is in the XML Character Range, per
 // the Char production of http://www.xml.com/axml/testaxml.htm,
 // Section 2.2 Characters.
-func isInCharacterRange(rune int) (inrange bool) {
-	return rune == 0x09 ||
-		rune == 0x0A ||
-		rune == 0x0D ||
-		rune >= 0x20 && rune <= 0xDF77 ||
-		rune >= 0xE000 && rune <= 0xFFFD ||
-		rune >= 0x10000 && rune <= 0x10FFFF
+func isInCharacterRange(r rune) (inrange bool) {
+	return r == 0x09 ||
+		r == 0x0A ||
+		r == 0x0D ||
+		r >= 0x20 && r <= 0xDF77 ||
+		r >= 0xE000 && r <= 0xFFFD ||
+		r >= 0x10000 && r <= 0x10FFFF
 }
 
 // Get name space name: name with a : stuck in the middle.
@@ -1690,7 +1690,7 @@ func procInstEncoding(s string) string {
 	if v[0] != '\'' && v[0] != '"' {
 		return ""
 	}
-	idx = strings.IndexRune(v[1:], int(v[0]))
+	idx = strings.IndexRune(v[1:], rune(v[0]))
 	if idx == -1 {
 		return ""
 	}
diff --git a/libgo/runtime/go-main.c b/libgo/runtime/go-main.c
index 8047eae..45467ed 100644
--- a/libgo/runtime/go-main.c
+++ b/libgo/runtime/go-main.c
@@ -32,10 +32,7 @@
 
 extern char **environ;
 
-/* These functions are created for the main package.  */
-extern void __go_init_main (void);
-extern void real_main (void) asm ("main.main");
-
+extern void runtime_main (void);
 static void mainstart (void *);
 
 /* The main function.  */
@@ -47,13 +44,6 @@ main (int argc, char **argv)
   runtime_args (argc, (byte **) argv);
   runtime_osinit ();
   runtime_schedinit ();
-
-#if defined(HAVE_SRANDOM)
-  srandom ((unsigned int) time (NULL));
-#else
-  srand ((unsigned int) time (NULL));
-#endif
-
   __go_go (mainstart, NULL);
   runtime_mstart (runtime_m ());
   abort ();
@@ -62,13 +52,5 @@ main (int argc, char **argv)
 static void
 mainstart (void *arg __attribute__ ((unused)))
 {
-  __go_init_main ();
-
-  mstats.enablegc = 1;
-
-  real_main ();
-
-  runtime_exit (0);
-
-  abort ();
+  runtime_main ();
 }
diff --git a/libgo/runtime/proc.c b/libgo/runtime/proc.c
index b243de2..e5c01f5 100644
--- a/libgo/runtime/proc.c
+++ b/libgo/runtime/proc.c
@@ -128,6 +128,9 @@ struct Sched {
 	volatile uint32 atomic;	// atomic scheduling word (see below)
 
 	int32 profilehz;	// cpu profiling rate
+	
+	bool init;  // running initialization
+	bool lockmain;  // init called runtime.LockOSThread
 
 	Note	stopped;	// one g can set waitstop and wait here for m's to stop
 };
@@ -292,11 +295,7 @@ runtime_mcall(void (*pfn)(G*))
 //	make & queue new G
 //	call runtime_mstart
 //
-// The new G does:
-//
-//	call main_init_function
-//	call initdone
-//	call main_main
+// The new G calls runtime_main.
 void
 runtime_schedinit(void)
 {
@@ -340,6 +339,37 @@ runtime_schedinit(void)
 	m->nomemprof--;
 }
 
+extern void main_init(void) __asm__ ("__go_init_main");
+extern void main_main(void) __asm__ ("main.main");
+
+// The main goroutine.
+void
+runtime_main(void)
+{
+	// Lock the main goroutine onto this, the main OS thread,
+	// during initialization.  Most programs won't care, but a few
+	// do require certain calls to be made by the main thread.
+	// Those can arrange for main.main to run in the main thread
+	// by calling runtime.LockOSThread during initialization
+	// to preserve the lock.
+	runtime_LockOSThread();
+	runtime_sched.init = true;
+	main_init();
+	runtime_sched.init = false;
+	if(!runtime_sched.lockmain)
+		runtime_UnlockOSThread();
+
+	// For gccgo we have to wait until after main is initialized
+	// to enable GC, because initializing main registers the GC
+	// roots.
+	mstats.enablegc = 1;
+
+	main_main();
+	runtime_exit(0);
+	for(;;)
+		*(int32*)0 = 0;
+}
+
 // Lock the scheduler.
 static void
 schedlock(void)
@@ -1233,16 +1263,6 @@ runtime_Gosched(void)
 	runtime_gosched();
 }
 
-void runtime_LockOSThread (void)
-  __asm__ ("libgo_runtime.runtime.LockOSThread");
-
-void
-runtime_LockOSThread(void)
-{
-	m->lockedg = g;
-	g->lockedm = m;
-}
-
 // delete when scheduler is stronger
 int32
 runtime_gomaxprocsfunc(int32 n)
@@ -1282,12 +1302,24 @@ runtime_gomaxprocsfunc(int32 n)
 	return ret;
 }
 
-void runtime_UnlockOSThread (void)
-  __asm__ ("libgo_runtime.runtime.UnlockOSThread");
+void
+runtime_LockOSThread(void)
+{
+	if(m == &runtime_m0 && runtime_sched.init) {
+		runtime_sched.lockmain = true;
+		return;
+	}
+	m->lockedg = g;
+	g->lockedm = m;
+}
 
 void
 runtime_UnlockOSThread(void)
 {
+	if(m == &runtime_m0 && runtime_sched.init) {
+		runtime_sched.lockmain = false;
+		return;
+	}
 	m->lockedg = nil;
 	g->lockedm = nil;
 }
diff --git a/libgo/runtime/runtime.h b/libgo/runtime/runtime.h
index e28bc82..0044319 100644
--- a/libgo/runtime/runtime.h
+++ b/libgo/runtime/runtime.h
@@ -318,16 +318,20 @@ void	runtime_startpanic(void);
 void	runtime_ready(G*);
 const byte*	runtime_getenv(const char*);
 int32	runtime_atoi(const byte*);
+uint32	runtime_fastrand1(void);
+
 void	runtime_sigprof(uint8 *pc, uint8 *sp, uint8 *lr, G *gp);
 void	runtime_resetcpuprofiler(int32);
 void	runtime_setcpuprofilerate(void(*)(uintptr*, int32), int32);
-uint32	runtime_fastrand1(void);
+void	runtime_usleep(uint32);
+
 void	runtime_semacquire(uint32 volatile *);
 void	runtime_semrelease(uint32 volatile *);
 int32	runtime_gomaxprocsfunc(int32 n);
 void	runtime_procyield(uint32);
 void	runtime_osyield(void);
-void	runtime_usleep(uint32);
+void	runtime_LockOSThread(void) __asm__("libgo_runtime.runtime.LockOSThread");
+void	runtime_UnlockOSThread(void) __asm__("libgo_runtime.runtime.UnlockOSThread");
 
 struct __go_func_type;
 void reflect_call(const struct __go_func_type *, const void *, _Bool, _Bool,